Wenchuan earthquake caused huge casualties and economic losses, The damage to housing construction accounted for a large proportion. In recent years, focus of the study question is how fast and accurate understanding seismic capacity of group building and post-earthquake losses in urban areas. Vulnerability analysis of building structures is an important component of earthquake loss estimation. It has important practical significance for various cities and regions to develop reasonable earthquake disaster mitigation planning and emergency response.
This paper studies the following aspects:
(1) The choice of vulnerability analysis method has significant impact on the results of earthquake loss estimation. Therefore, this paper studies the correlation between seismic peak acceleration and damage indices of sructure from the perspective of the relevance of random variables. A case study of the masonry and frames select different damage indices. Studies have shown that peak ground acceleration values have best correlation with transcendence intensity rate for the masonry and have better correlation with inter-story drift ratio for frames.
(2) This paper studies total probabilistic seismic risk analysis of single and group buildings. The used method that is simple and practical can be used to assess the comprehensive seismic capacity of cities in China. Seismic vulnerability analysis adopts peak ground acceleration as earthquake input and considers the uncertainty of ground motion parameters. Finally the probabilistic results of seismic damage to the structure in design reference period can be acquired. A case study of the masonry with constructional columns verify the accuracy of the method.
(3) This paper focuses on the group vulnerability of buildings and puts forward a new fast evaluation approach of group vulnerability for post-earthquake. Impersonal weight determination by entropy method and similarity theory in fuzzy mathematics are introduced in group vulnerability analysis, which can evaluate earthquake disaster of group buildings rapidly and reliably. Group vulnerability analysis method presented in the paper is applied in masonry and frames. By studying the seismic capacity similarity of typical known monomer and unknown monomer,Further vulnerability result of unknown monomer is obtained by the vulnerability of the typical monomer. Finally the result of group vulnerability can be obtained by statistical analysis.
(4) This paper combines structural vulnerability analysis with performance-based seismic design concept. It can assess the seismic performance of existing buildings.
In addition, the economic losses caused by the earthquake have been studied. A direct economic loss model which considers structure of different uses is proposed. Finally it can obtain the assessment of total cost of structures during the whole life-cycle and provide reference for the application performance-based seismic design.
Article Source: Technology Science Articles Information Technology Articles
4/12/2010
Energy Diversification Pathway of China for Energy Security
The rapid increase in energy consumption has brought issues such as energy supply and demand imbalance, which makes energy security has become an international subject of widespread concern. Environmental pollution and climate change caused by energy use also seriously threat the sustainable economic development. As the world's fast-growing economies, China's energy demand particularly strong. While, China accounted for nearly three-quarters of global energy consumption growth in 2008.
How to ensure energy security has also become China's a great challenge.As an important strategy for energy security, the theoretical significance and practical value of energy diversification have gradually caught scholars and policy-makers' attention. Diversification of energy resources reduces the over-reliance on a single or few energy options through the provision of multiple choices. Since it can reduce the risk of supply disruptions on one hand, and ensure that energy use does not cause irreversible impacts on the environment on the other hand, Energy Diversification is an important means to ensure energy security from the system level.This paper first analyzed the research background and theoretical relevance of this subject, and straightened out the existing research home and abroad, summed up the research trends and weaknesses.
Then, based on defining energy diversification and energy security, used the energy economic theory to systematically analyze the relationship between energy diversification and energy security, then from the point of view of portfolio theory, analyzed diversification the scope of the role of energy security. Next, build the energy security-oriented MDA model of China's energy diversification, using time-series data on energy consumption to dynamic analysis China's diversity and energy security performance of the. Then, analyzed the multiple trades-offs during diversification path selection process. Based on establishment of system performance optimization models in different contexts, establish the optimal combination selection mechanism of China's energy diversification from the system level. Try to explore a diversification path selection method with a combination of resources and socio-economic conditions. Finally, in summing up the study of this paper, gave some policy recommendations for China's energy diversification.
Article source: Information Technology Articles.com/
How to ensure energy security has also become China's a great challenge.As an important strategy for energy security, the theoretical significance and practical value of energy diversification have gradually caught scholars and policy-makers' attention. Diversification of energy resources reduces the over-reliance on a single or few energy options through the provision of multiple choices. Since it can reduce the risk of supply disruptions on one hand, and ensure that energy use does not cause irreversible impacts on the environment on the other hand, Energy Diversification is an important means to ensure energy security from the system level.This paper first analyzed the research background and theoretical relevance of this subject, and straightened out the existing research home and abroad, summed up the research trends and weaknesses.
Then, based on defining energy diversification and energy security, used the energy economic theory to systematically analyze the relationship between energy diversification and energy security, then from the point of view of portfolio theory, analyzed diversification the scope of the role of energy security. Next, build the energy security-oriented MDA model of China's energy diversification, using time-series data on energy consumption to dynamic analysis China's diversity and energy security performance of the. Then, analyzed the multiple trades-offs during diversification path selection process. Based on establishment of system performance optimization models in different contexts, establish the optimal combination selection mechanism of China's energy diversification from the system level. Try to explore a diversification path selection method with a combination of resources and socio-economic conditions. Finally, in summing up the study of this paper, gave some policy recommendations for China's energy diversification.
Article source: Information Technology Articles.com/
The Research of Magnetic Driver Simulation System for Magnetic Pump
The magnetic drive system of the magnetic driver pump is usually composed of inner magnetic rotor、and containment shell. The inner magnetic rotor connect with the being transmissioned parts, and the outer magnetic rotor connect with the transmission parts. Magnetic transmission has the function of Elastic coupling vibration absorption, and to the point, it can completely seal the inner magnetic rotor and the being transmissioned parts. Without the mechanical contact,it also can pass the kinematic and dynamic of the transmission parts to the being transmissioned parts by magnetic action, so that the dynamic seal becomes to static seal.
Therefore, magnetic drive is wildly used in the environment of which has some special demands of seal, such as petroleum, chemical, pharmacy, food and aviation field.During the design and calculating of magnetic drivers, the process "preliminary design—modeling—analysis—revision—re-design—re-modeling—re-analysis"will be carried out repeatedly, and the process are operated complex the requirement to Users is too much, and the user be apt to make mistake during the processing. To solve the problems mentioned above, the study has developed a magnetic driver simulation system. This system contains three parts: parametric design, Parametric modeling and parametric finite element.The study of 3D parametric design system is based on characteristics of the structure of the cylinder typed radial magnetic drive, design flow and design method.
This system Use Solid Works as the supporting platform and take VB language to do the secondary development of the API function of Solid Works. It can realize the auto-modeling and assembling of every parts of the magnetic drive.Based on ANSYS, the study use vector potential method and scalar potential method to build 2D, 3D models of the magnetic field of cylinder typed radial magnetic drive, then do the solution computation and analysis the distribution of magnetic line, the distribution of magnetic induction, the size of the moment of magnetic force and the size of eddy current. A template for magnetic drivers structure calculating and analysis based on ANSYS is built.
The system possesses the following features:
1. A method of parametric finite element analysis for magnetic drivers is presented in this system, the FEA model is droved by the parameters.
2. through proceeding communication mechanism of Windows, the centre of control based on passages is formed. it can be use the ANSYS as a subprogram.The developed magnetic driver simulation system, under the different design parameter, is advantageous for the magnetic driver to rebuild the model fast, and carry on the finite element simulation analysis . The above conclusion and the method have enriched the magnetic driver research contend, and explored a lower consumption higher quality design and analysis method.
Article source from:http://www.latest-science-articles.com/Technology_Science/ and http://information-technology-articles.com/
Therefore, magnetic drive is wildly used in the environment of which has some special demands of seal, such as petroleum, chemical, pharmacy, food and aviation field.During the design and calculating of magnetic drivers, the process "preliminary design—modeling—analysis—revision—re-design—re-modeling—re-analysis"will be carried out repeatedly, and the process are operated complex the requirement to Users is too much, and the user be apt to make mistake during the processing. To solve the problems mentioned above, the study has developed a magnetic driver simulation system. This system contains three parts: parametric design, Parametric modeling and parametric finite element.The study of 3D parametric design system is based on characteristics of the structure of the cylinder typed radial magnetic drive, design flow and design method.
This system Use Solid Works as the supporting platform and take VB language to do the secondary development of the API function of Solid Works. It can realize the auto-modeling and assembling of every parts of the magnetic drive.Based on ANSYS, the study use vector potential method and scalar potential method to build 2D, 3D models of the magnetic field of cylinder typed radial magnetic drive, then do the solution computation and analysis the distribution of magnetic line, the distribution of magnetic induction, the size of the moment of magnetic force and the size of eddy current. A template for magnetic drivers structure calculating and analysis based on ANSYS is built.
The system possesses the following features:
1. A method of parametric finite element analysis for magnetic drivers is presented in this system, the FEA model is droved by the parameters.
2. through proceeding communication mechanism of Windows, the centre of control based on passages is formed. it can be use the ANSYS as a subprogram.The developed magnetic driver simulation system, under the different design parameter, is advantageous for the magnetic driver to rebuild the model fast, and carry on the finite element simulation analysis . The above conclusion and the method have enriched the magnetic driver research contend, and explored a lower consumption higher quality design and analysis method.
Article source from:http://www.latest-science-articles.com/Technology_Science/ and http://information-technology-articles.com/
3/28/2010
Synchronization Technologies for OFDM on the System of Satellite Communication
Satellite communications is an important component of the the world's communication networks and has become an indispensable means of communication in modern society. Wireless communication technology Based on orthogonal frequency division multiplexing (OFDM) is in rapid development. OFDM can provide high-capacity information transmission and Solve the issue of wireless Channel performance variation when the channel of high-speed data transmission in the mobile terminal, which greatly improve the quality of transmission channel. OFDM technology has the character of anti-multipath fading, high spectral efficiency, and so on, which is suitable for satellite communications with high-speed transmission in the wireless environment. In order to achieve a real sense of the OFDM system, synchronization is a critical issue.
At first, the current satellite communications and the development of OFDM technology are introduced in this paper, which is the research background of the subject. Some problems in the satellite communications and the necessary of OFDM technology applied for satellite communications are discussed.Second, the importance of the satellite communication channel in the analysis and designing of communication systems is discussed. The characteristics of satellite channels and the propagation characteristics described in detail. The probability density function of the satellite channels as well as the satellite channel model is analyzed.OFDM system and its synchronization technology are studied, the basic principles of OFDM are introduced and OFDM system model is given. The OFDM synchronization and synchronization technology are focused on the basis of analysis the factors of Synchronization in a variety of non-ideal. Various synchronization methods and improved synchronization algorithm of satellite communications based OFDM are analyzed on the basis of channel model and the corresponding results of computer simulation are given.At last, low-orbit satellite communication system is introduced, and the mode of satellite channels in the theoretical analysis is further simplified. On the analysis of low-orbit satellites, the effects of low signal to noise ratio and Doppler frequency shift Focus on considered. Synchronization of carrier frequency under the low signal to noise ratio of low-orbit satellites is analyzed in this paper, including the degradation of the capture performance under low signal to noise ratio and the design of loop carrier.
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3/26/2010
Organic Structure Probes and Studies Modern Interior Space
Today's society has been large-scale industrial production from the machine to the era of knowledge economy era, Chaos Theory, Phenomenology and symbiotic way of thinking in different aspects of objective and rational to the spirit and challenge Anthropocentrism, mechanical materialism by the sublimation of uncertainty to the complex and ever-changing organic synthesis.In the design of architectural space, organic thinking has never been a new, Wright proposed the theory of organic architecture, organic form of Gaudi architecture made attempts, Kisho Kurokawa more symbiotic with its philosophy, so that a comprehensive theory of organic development. Function in the beyond, and to go beyond the simple people-centered development of a sound, the interior space of the organic structure was established on the grounds. Interior space of the aesthetic orientation of the organic structure is diversified.
Contemporary architectural creation around the world, we can see that more and more interior space into the design of the idea of organic, even though very few people claim to be organic interior designers, but we can not deny the impact of the ideological role of organic. Spatial form and follow a straight line no longer advocate the design, but bold organic form; designed not only to emphasize the concept of self, but seek harmonious integration into the environment; design pattern is no longer the lingua franca of international style, but the search for geographical features, emphasize here and now; so on and so forth, are all in line with the organic philosophy.Representative of the organic concept is not a style, but more style, and it gave birth to the idea of ecological aesthetics, this is a new, beyond the form or function on a purely aesthetic form, a contact is the most the oldest living forms and the most distant prospect of the future survival of the survival of the aesthetic situation.
In this background, the interior space and the environment, and urban space, indoor space and the relationship between human beings has become the focus of thinking about the object, the modern architecture of the static and pure geometric point of view, must be changed from time to time.
Contemporary architectural creation around the world, we can see that more and more interior space into the design of the idea of organic, even though very few people claim to be organic interior designers, but we can not deny the impact of the ideological role of organic. Spatial form and follow a straight line no longer advocate the design, but bold organic form; designed not only to emphasize the concept of self, but seek harmonious integration into the environment; design pattern is no longer the lingua franca of international style, but the search for geographical features, emphasize here and now; so on and so forth, are all in line with the organic philosophy.Representative of the organic concept is not a style, but more style, and it gave birth to the idea of ecological aesthetics, this is a new, beyond the form or function on a purely aesthetic form, a contact is the most the oldest living forms and the most distant prospect of the future survival of the survival of the aesthetic situation.
In this background, the interior space and the environment, and urban space, indoor space and the relationship between human beings has become the focus of thinking about the object, the modern architecture of the static and pure geometric point of view, must be changed from time to time.
The Bathroom Space Design of Based upon Universal Design
Universal design of products and environmental is non-adaptive and specific, can be used by as many people as possible and the best condition is used by all people. Universal design includes the principles of a barrier-free design and architectural design of the elderly. This design is benefit not only to the disabled, the elderly , but also to the healthy. It is truly reflects the "people-oriented" ideas, reflected the ethics of science and technology of and social responsibility. The ideal of universal design can be used for all products, this ideal state of the elderly for the barrier-free design and architectural design guidelines for the direction of development. This thesis discussion the residential design of sanitary facilities based on the current and future aging of China's population situation worsening, as well as the trend of the housing industry. The three elements of universal design in the architectural design are human being, and building construction, as well as interactive and interdependent relationship.
This thesis to meet the aging society, sanitary facilities and space for study, to universal design theory as a guide, combined with ergonomics, gerontology, psychology and other related knowledge, systematic analysis of the elderly, physical, psychological characteristics and rest patterns . By empirical research on the existing bathroom space for the elderly in the design and use of existing in-depth study of issues in order to seek appropriate measures and means of rational solution is proposed to enhance the subjective well-being of older people as the goal of design ideas. After the results of the analysis, the thesis is proposed space bathroom design principles of universal design and design methods and the elderly and human-scale projection and amendments carried out.
More information please visit Technology Science or http://www.latest-science-articles.com
This thesis to meet the aging society, sanitary facilities and space for study, to universal design theory as a guide, combined with ergonomics, gerontology, psychology and other related knowledge, systematic analysis of the elderly, physical, psychological characteristics and rest patterns . By empirical research on the existing bathroom space for the elderly in the design and use of existing in-depth study of issues in order to seek appropriate measures and means of rational solution is proposed to enhance the subjective well-being of older people as the goal of design ideas. After the results of the analysis, the thesis is proposed space bathroom design principles of universal design and design methods and the elderly and human-scale projection and amendments carried out.
More information please visit Technology Science or http://www.latest-science-articles.com
3/24/2010
A Study of Government Administration and Supervision of Construction Quality
This dissertation has systematically studied the organization systems, mechanism, actions, phases of government supervision, and main part administration and supervision. The main contents are summarized as follows:Organizational systems and mechanism. For organizational systems, this dissertation, based on the theories of systems engineering, management, economics and government regulation, exposes eight traits of government management and supervision, including systematic character, objective inherence, legislation character, social character, market, economic character, service character and international character.
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A Study of Government Administration and Supervision of Construction Quality
Resource From:
A Study of Government Administration and Supervision of Construction Quality
A Study on Capital Management of Forest Ecological Compensation in China
Based on the great development of China the fact that the forest ecological compensation has become a key policy of national economy and social development. With using as a reference the past research results, the paper makes a comparatively comprehensive study on the capital management problems such as the sources, expenditures, effects, supervision and assessment of forest ecological compensation for the project of natural forest reservation.
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A Study on Capital Management of Forest Ecological Compensation in China
Resource From:
A Study on Capital Management of Forest Ecological Compensation in China
3/15/2010
The Research on the Governance-oriented Audit Model
The 21st century is the times of the corporate governance. Currently,no matter the academic research on modern company system or the arrange of company correlation work, is aiming at the corporate governance. In post-Enron era, there are more and more attentions to corporate governance and financial frauds, which have brought a great influence on the development of auditing.
Resource from:The Research on the Governance-oriented Audit Model
Resource from:The Research on the Governance-oriented Audit Model
3/10/2010
Research on D0A Estimation Algorithm in Smart Antenna
In smart antenna systems, digital signal process technologies are used to produce spatial and directional beam to aim the main beam at the coming direction of user signal of interest with the side lobe aiming at the coming direction of signal of interference user so that the signals of the user of interest are made use of with great efficiency while the interference signals are eliminated or restrained.
Resource From:Research on D0A Estimation Algorithm in Smart Antenna
Resource From:Research on D0A Estimation Algorithm in Smart Antenna
Theoretical and Empirical Research on Legal Protection of Investor
On the basis of the legal protection of investors, the paper looks for mechanisms and channels to increase the degree of protection of shareholders, and confirms the propositions using countries' data.
Resource From: Theoretical and Empirical Research on Legal Protection of Investor
Resource From: Theoretical and Empirical Research on Legal Protection of Investor
3/05/2010
Clinical Significance of ATP-tumor Chemosensitivity Assay (ATP-TCA) in Chemotherapy of Advanced Breast Cancer
Objective:1. To study whether ATP chemosensitivity assay(ATP-TCA) test can direct clinical chemotherapy.2. ATP in vitro method to explore whether there is any experimental drugs to reduce toxicity.Methods:1. 56 cases of patients with non-surgical advanced breast cancer patients were tested by the ATP-TCA as the research group; The other 56 cases of patients with non-surgical advanced breast cancer patients weren’t tested by the ATP-TCA as the control group. Compare two group’s clinical outcome after six cycles’(one cycle for twenty-one days) chemotherapy.2. The two groups in the first 2 cycles (1 cycle 21d) after treatment compared toxicity .Results:1. The overall response rate of the research group was 86%(48/56) ,the control group was 49%(27/56). The research group shows better than the control group in alleviating symptoms, decreasing tumor size ,cutting down tumor markers of breast cancer such as CEA、CA15-3 and so on. In the research group,more than one year survival period was 83%(46/56);Correspondingly,th control group is 61%(34/56).The research group is more significantly than the control group in Clinical effect (P<0.05).2. Study group and control group toxicity of mainly bone marrow suppression, gastrointestinal reactions, alopecia and mucositis. Reaction in which the digestive tract was significantly (P<0.05), and bone marrow suppression, alopecia and mucositis was no significant difference.Conclusions: 1. The ATP—TCA has preferable value to direct the chemotherapy of advanced breast cancer,which can prolong the survival period , which can improve the clinic curative effect.2. ATP in vitro tumor cell culture + sensitivity test of advanced breast cancer chemotherapy drug can avoid the use of ineffective drugs toxicity.
The Effect of Ketamine on the Learning and Memory Function of the Sprague-Dawley Rat's Offspring
Objective:To study the effects of ketamine general anesthesia during gestationperiod on the learning and memory functions of Sprague-Dawley rat,s offspring.
Method:Thirty pregnant Sprague-Dawley (SD) rats were randomly divided into ketamine group and Control group,fifteen in each group. Ketamine was injected intravenously to the rats in the ketmine group for 2 hours, While ketmine was replaced with eaqual volume physiological saline solution for the rats in the control group.The learning and memory functions of the offspring rats were tested by Morris water maze test at different postnatal time intervals,20 days and 30 days respectively.The morphological changes of hippocampus tissue were analyzed under electrical microscope for the offspring rats. At the same time, the expression of the immediate early genes, c-fos and c-jun, were checked by RT-PCR.
Result:The latent period of the offspring rats in ketamine group was longer than that in the control group at 20 days and 30 days postnatly. The latent period of the second times of the offspring rats in ketamine group was significantly longer than that in the control group at 30 days postnatly (p<0.05). The hippocampus tissue of the offspring rat,s in the ketmine group was significantly damaged. The expression of the immediate early genes, c-fos and c-jun, appeared in both the offspring of the two groups and their gray value were equal.
Conclusion:Ketmine general anesthesia during gestationperiod could cause learning and memory functional injury to the offspring rats.It is related to the neuronal damage in the hippocampal tissue caused by ketmine.
Method:Thirty pregnant Sprague-Dawley (SD) rats were randomly divided into ketamine group and Control group,fifteen in each group. Ketamine was injected intravenously to the rats in the ketmine group for 2 hours, While ketmine was replaced with eaqual volume physiological saline solution for the rats in the control group.The learning and memory functions of the offspring rats were tested by Morris water maze test at different postnatal time intervals,20 days and 30 days respectively.The morphological changes of hippocampus tissue were analyzed under electrical microscope for the offspring rats. At the same time, the expression of the immediate early genes, c-fos and c-jun, were checked by RT-PCR.
Result:The latent period of the offspring rats in ketamine group was longer than that in the control group at 20 days and 30 days postnatly. The latent period of the second times of the offspring rats in ketamine group was significantly longer than that in the control group at 30 days postnatly (p<0.05). The hippocampus tissue of the offspring rat,s in the ketmine group was significantly damaged. The expression of the immediate early genes, c-fos and c-jun, appeared in both the offspring of the two groups and their gray value were equal.
Conclusion:Ketmine general anesthesia during gestationperiod could cause learning and memory functional injury to the offspring rats.It is related to the neuronal damage in the hippocampal tissue caused by ketmine.
The Rap-style Bone Stress Stimulator on Accelerating Fracture Healing
Background: Fracture healing is regulated by the local mechanical environmen, and can be significantly promoted by proper stress. A rap-style bone stress stimulator had been developed based on this principle by our group, and had obtained the national invention patent.
Objective: To explore the effect of the rap-style bone stress stimulator on accelerating fracture healing.
Methods:Ten male grey goats of the same species were randomly collected. All the goats were performed with bilateral tibial transverse osteotomy and plate fixation, the right tibias undewent stress stimulation as the experimental group, the left didn't as the self-control group. Study factor treatment was started at the first day post operation and persevered for 12 weeks. Radiographs were taken for each tibia at the first day and the end of every four weeks after surgery. All animals were killed at the 12th weekend, bilateral complete tibias were obtained for three-point bending mechanical test and torsion test, the data was processed by SPSS V13.0. After the biomechanical tests, histological sections of the callus tissue were stained by HE and Masson method to assess the level of maturity.Results: All the animals had healed, and no reaction had been seen. The quality and quantity of callus of the experimental group was better than that of the control group by observing X-ray at the same time point. The results of Biomechanical tests suggested that three-point bending static rigidity, maximum load and torsional static rigidity of callus of the experimental group were significantly higher than that of the control group(P=0.000). The histomorphometry tests pointed out that the callus of the experimental group was more mature than that of the control group.
Conclusion: Fracture healing should be promoted significantly by the rap-style bone stress stimulator, and the basis for the next clinical trials could be provided by this study.
Objective: To explore the effect of the rap-style bone stress stimulator on accelerating fracture healing.
Methods:Ten male grey goats of the same species were randomly collected. All the goats were performed with bilateral tibial transverse osteotomy and plate fixation, the right tibias undewent stress stimulation as the experimental group, the left didn't as the self-control group. Study factor treatment was started at the first day post operation and persevered for 12 weeks. Radiographs were taken for each tibia at the first day and the end of every four weeks after surgery. All animals were killed at the 12th weekend, bilateral complete tibias were obtained for three-point bending mechanical test and torsion test, the data was processed by SPSS V13.0. After the biomechanical tests, histological sections of the callus tissue were stained by HE and Masson method to assess the level of maturity.Results: All the animals had healed, and no reaction had been seen. The quality and quantity of callus of the experimental group was better than that of the control group by observing X-ray at the same time point. The results of Biomechanical tests suggested that three-point bending static rigidity, maximum load and torsional static rigidity of callus of the experimental group were significantly higher than that of the control group(P=0.000). The histomorphometry tests pointed out that the callus of the experimental group was more mature than that of the control group.
Conclusion: Fracture healing should be promoted significantly by the rap-style bone stress stimulator, and the basis for the next clinical trials could be provided by this study.
2/22/2010
Study on the New Genes of Sow Fertility
After corresponding analysis of the relationship with sow gestation,three Expressed sequence tag(CK455976、CK465614 and CO986776)on the top of Sow gestation relevant gene regulatory networks which was constructed by former researcher in our laboratory was selected to do forward research.Using the total RNA extracted from sow ovaries(85-days-pregnacy) and primers designed according to the sequence of these EST,cDNA complete sequence of these three genes have been obtained using RT-PCR and RACE-PCR technology.And after bioinformatics analysis, tissue expressed analysis and chromosome location,we got the results:(1) The full-length cDNA sequence from the porcine CK455976 were cloned,and the cDNA was 596bp with an entire open reading frame,encoding 117 amino acids.The sequences have been deposited in GenBank database,the accession number is FJ436413. The predicted nucleotide sequence similarity with human,mouse,dog and macaca mulatta DPPA5 gene were respectively 83%,70%,80%,83%,and the amino acid sequence were respectively 74%,55%,69%,74%.The INRA-Minnesota porcine radiation hybrid panel(IMpRH) were employed to determine the chromosomal locations of the DPPA5.The DPPA5 was localized to 1p1.3,with close linkage to SW1123 (LOD=5.82).(2) The full-length cDNA sequence from the porcine CK465614 was cloned.The sequences have been deposited in GenBank database,the accession number is FJ750950. The longth of complete sequence is 5003bp,contain an open reading frame which codes a polypeptide of 362 amino acids.The predicted nucleotide sequence similarity with human,mouse,cattle,horse,dog and macaca mulatta FP gene were respectively 77%,81%,81%,80%,89%,74%and the amino acid sequence were respectively 66.3%, 82.8%,87.6%,86.4%,86.6%,85.9%.There were a G-protein linked receptor family at 43-304 position(Prosite:PS50262,Score20.693).IMpRH was used for determining the chromosomal regional location of the pig FP gene,The result of the data analysis indicated that FP gene was mapped to the region of SSC6q31-q32,with close linkage to SW16472(LOD=12.61)and S0299(LOD=10.56),and normal linkage to SWR726 (LOD=6.79).Result of RT-PCT revealed that FP gene was highly expressed in ovary and endometrium,followed by spleen,heart,kidney,stomach,and no expressed in liver.(3) The full-length cDNA sequence from the porcine CO986776 was cloned.The sequences have been deposited in GenBank database,the accession number is FJ603023. The longth of complete sequence is 2585bp,contain an open reading frame which is codes a polypeptide of 176 amino acids.The predicted nucleotide sequence similarity with human,mouse,cattle and macaca mulatta MAL2 gene were respectively75%, 70%,81%,74%and the amino acid sequence were respectively90%,90%,93%,84%. Constructive domain analysis by ExPASy ScanProsite indicate that there is a MARVEL domain(Prosite:PS51225,Score 15.143) at 31-175 position.The result of the data analysis indicated that MAL2 gene was mapped to the region of SSC4p12-p13, with close linkage to SWR73(LOD=6.38) and normal linkage to S0001(LOD=6.35) and SWR2179(LOD=5.07).Result of RT-PCT revealed that MAL2 gene was highly expressed in stomach,followed by liver,kidney,endometrium,ovary,and no expressed in heart and spleen.
Effects of Biogas Residue on the Nature of Substrate and Growth of Tomato in Greenhouse
In this experiment,three compound substrates with biogas residue and Coal cinder,as well as pure biogas residue and pure coal cinder were used as substrate for greenhouse tomato cultivation.The treatments were as follows:(T1) pure coal cinder,(T2) 1 biogas residue + 3coal cinder(ⅴ/ⅴ),(T3) 1 biogas residue + 1 coal cinder,(T4) 3 biogas residue + 1 coal cinder,(T5) pure biogas residue.The experiment was taken by potted plants and the pot was 6 liter.The experiment had 5 treatments,each treatment with 5 pots,one plant each pot,and 3 replicates,and it was designed by randomized block. The physical and chemical properties,enzyme and microbiology of the substrate and the tomato plant growth and development,fruit quality and yeild were determinated.The major results were as follows:1.Biogas residue increased the value of pH and EC of substrate.In the course of plant growth, the value of pH in substrate changed differently,and the pH value of T1 and T2 increased slghly, While the pH value of T4 and T5 decreased slightly,that was the of pH value in substrates with higher content of biogas residue increased,while the pH value in substrate with higher content of coal cinder decreased during the growth of tomato plant.The main reason for the pH increasing was that:first, decomposition of biogas residue released plenty of nutrients,and the more residue biogas the more nutrients were released;second,the transpiration of tomato plants relatively increased,both of which had increased the Ca2+,Mg2+ and other ions' accumulation in substrates.The EC value of T1,T2,T3 decreased,of which the EC value of T3 was appropriate and decreased little,and the EC value of T4 and T5 increased first and decreased later,which reflected that biogas residue had characteristics of slow and long-lasting nutrient releasing.As result of containing large biogas residue,the EC value of T4 and T5 were as high as 3.14 ms·cm-1、3.39 ms·cm-1 respectively which led to a certain degree of salt accumulation It was entirely feasible to use a certain percentage of biogas residue and coal cinder as compound substrates for soilless cultivation,and T3 had the best properties,with bulk density between 0.46g·cm-3 and 0.48g·cm-3,EC value between 1.95 ms·cm-1 and 2.58 ms·cm-1x.2.Biogas residue improved the number of microorganisms in substrate.The results showed that the number of bacteria,actinomyces,fungi,cellulose-decomposing bacteria increased with the increase of the content of biogas residue in substrates;as compared with pure coal cinder substrate, substrates with biogas residue significantly increased the number of various types of microorganisms, especially improved the distribution of rhizosphere microorganisms in soilless culture substrate.Pure biogas residue treatment had a largest effect on microorganisms,which had the most number of bacteria,actinomyces,fungi,cellulose-decomposing bacteria,they were 8.40～20.85×107cfu·g-1、3.2～46.00×106cfu·g-1、26.00～62.02×104cfu·g-1、0.94～14.03×106cfu.g-1 respectively.Biogas residue promoted the proliferation of microorganisms to speed up the decomposition of organic matter and nutrients fixed to improve the effectiveness and utilization of nutrients.3.Biogas residue improved the activity of enzyme in substrate.The effects of different substrate treatments on the activity of enzyme showed that,as compared with pure coal cinder,substrates with biogas residue enhanced the activity of phosphatase,invertase,urease proteinase,cellulose significantly, in general,the activity of enzyme enhanced as the content of biogas residue increased in substrate,and the activity of invertase and urease were highest,in T5,while the activity of proteinase and cellulose were highest in T4.Substrate enzymes involved in biochemical processes in substrate,were closely related to the release and storage of nutrients,as well as the formation of humus,substrate structure and physical properties,as a result they could improve substrate activity and ability of nutrients transformation.4.Biogas residue increased tomato plant's height,stem diameter,leaf number and root activity. Tomato plants in substrates with more biogas residue had more vigorous stronger growth on height, stem diameter and leaf number.Biogas residue increased the root activity of tomato plants,highest record of root activity occurred in T4,followed by T5、T3、T2,and there were no significant differences with T4,but T4、T5、T3、T2 were significantly higher than T1 by 118%、67%、63%、20%respectively.5.Biogas residue improved tomato fruit's quality and yield.Biogas residue improved tomato fruit soluble sugar content,lowered titratable acid content,and increased the sugar/acid ratio,of which T3 was highest and reached 6.24;but biogas residue had little effects on vitamin C.Biogas residue increased tomato yield,T4 had the highest yield,followed by.T5、T3、T2,and the yield of T4,T5, T3,T2 were all significantly higher than the pure coal cinder treatment by 200%,190%,142%,129% respectively。6.In compound substrates,it is appropriate for tomato cultivation in greenhouse when the volume ratio of biogas residue is between 50%and 75%.
Experimental Study on Producing Different Grist with Extruder
With the rapid development of animal husbandry, extrusion technology has become an increasing concern as an important means of feed production. To improve the production capacity, reduce production costs and improve the adaptation of extruder to different raw materials have become the most urgent task now.The paper expatiated on the mechanism and process of grain extrusion, deduced yield model of the extrusion with reference to the screw extruder molding plastic theory. According to the extrusion theory as well as the production model, the effect of extruder configuration, screw speed, and raw materials to extruder specifications were also discussed.In this paper, a three-factor two-level orthogonal test was carried out. According to the analysis of test data, optimal configuration for soybean was gained. We can see that the screw speed affect output obviously, the higher the speed, the greater the extruder's output. Besides, when changing the speed, it is necessary to properly adjust the size of the screw configuration and dies to improve the screw transmission capacity of materials in case of plugging or steam back-flow in the extruder. For specific models, to select the best operating parameters can maximize utilization of extruder and improve economic efficiency. Rice bran, corn and wheat were also processed with ETS195 in this paper. The paper compared system parameters of extruder when processing different materials, and gave some suggestions for the Multi-functional Extruder processing different materials.
2/20/2010
Study on Policy of Government Payment for Rural Public Health in China
China is a society that separate city and rural area. The rural living and working environment is different with city. Government set a separate policy system for rural health development for a long time.ⅠThe goals and backgroundSome cases make me consider about some questions that relate with government payment for public health, such as, Should government be responsible for rural public health? If the compensation is necessary, which ways could be taken? Which health insurance system is active? How to select for government? Can they change the live of population? We decided study on policy of government payment for rural public health. To answer these questions, we have to learn about the history and background of policy framework. Then, select few key issues to discus further and find the theories to support these views. Finally, put forward reasonable suggestions based on discussion and theories.According to these questions and contents, we have to make literature review firstly. The goal is learn about the policy history for rural public health payment, the challenges and selected revolutions. Which level government should pay responsibility for rural public health payment? How about the relationship between central and local government? From the government, we can learn about the flow backs and the obstacles for rural public health payment through key person interview. Through investigation for health care institutes, learn about the standards and ways of government payment for supplies. Finally, we explore the relationship between health status and government payment through checking the national investigation result. These social methods are simple and operated for the team. we can get the goals of study through these methods.
In other sides, as we get the support from MOH, we can invite experts to evaluate the reports and give us more valuable suggestions in the whole process. The contribution of the study lie on identifying the framework of government payment for rural public health, help select the way of payment and explore development of rural health insurance system to direct the future policy selection.The increasing medical cost is the big challenge for Chinese health system. The increasing income level of individual is much lower than increasing medical expenditure level. In 1999, the individual income had increased by 288% and 222% in city and rural area than in 1990. Compare to clinical expenditure, the increasing rate is 625%. According to the data from National Bureau of Statistics of China, every family expends 1.92% of total income to health care service. In 1999, the rate had been 3.16%, and the poorer family, the higher rate. It is more difficult to compensate the health care service only depend on user fee. The health institutes face financial constrains and for the population, it is the necessary result of increasing self medical, decreasing the utility and access of health care. The equity of health care has been threatened and health demand could not be provided.From the result of the three health care investigations, the population covered by health insurance has decreased from 30.2% to 23.6% in 1993– 1998. The lack of health insurance is more serious in rural area. In 1993, the population that enjoys the health insurance is 12.8%, but just only 9% population could accept the health insurance. Most of the people have to pay for health care services that they need. The disease burden has been increased.That data show the health payment policy have some flow back for a long time, such as the payment framework is not good enough, the responsibility of government is not clear, the criteria of payment should be proved effectively, government should pay more attention to health care service in poor. Health payment policy is one of the key points in health reform progress. The evaluation criteria, such as access of health care, equity and effective, quality of health care, poor release, have been impacted by implementation of health payment policy.
The effective health payment policy will make great contribution for the success of health reform.The essay interviewed the framework of rural health payment from 1949, analysis the reason of health payment by using economic theory, political theory, and discussing the payment relationship between different level governments, the format of provider payment, and the development of supply payment through literature review, question investigation and deeply interview.
MethodsData collection methods: literature review, deep talking with key person, question investigationsData analysis method: describing and exploring, the concept and theory of economic, investment theory, cost theory, demand theory, limited resource, stakeholder analysis, valuable analysis.Quality control: In the design and prepare period, we invited expert to discuses the topic and took the pre-investigation for making sure the feasible and science. We try to select the right individuals and groups to investigate. Making sure the valuable second-hand material that had been collected from Analysis Report of National Health Services survey, etc.
The resultsDraft the government health payment frameworks in different periods through induction of history literature and analysis the frameworks by using political theory. Make sure the development and direction of health payment policy and get the common policy characters in different time. The goal of policy is more and more clear and detail. Compare to the two goals described in different periods, we can get the conclusion. The responsibility of different level government is more and more clear. The financial decentralization had been the basic of health payment policy. Government gradually becomes the main body of health payment from 2002. Payment has become the main action to attract excellent staff. The people began explore more financial payment for health care providers from just based on institutes ability. The shortage of the original format is that the health care providers will get more financial payment through increasing beds and staff. The modern criteria are based on output of health care and utility. These changes show the development of society.Analysis the important function, policy goal, coverage of research, challenge and standard of government health payment through using the theory of rural economic, public health, health investment, equity and effective. Discuss about the relationship among health provider, health insurance, utility of health care service and government payment. Finally, we get the basic theory framework of government health payment. Interview with policy makers and operators from different province and collect some key information to learn about the key impact elements, different character and problems.In western province, the health payment need be supported by central financial and the ability of local government is limited. Health payment focused on renew of equipments, but the quality of staff and service should be improved by taking right payment way. In middle province, the interviewer hope to increase the degree of financial transfer, change the structure of health payment, strengthen the input for township hospital and other public health institutes and build the sustainable system of health payment. In east province, local governments have enough ability to pay for the rural public health, but the payment direction is not clear and the waste is serious. From these results, we can get the conclusion that the low equity and effective of government health payment is common challenge.
DiscussionsDue to the imbalance of health payment in different province, we classified the public health as four types. Global public health services (infection disease monitoring, STD and AIDS monitoring) usually are paid attention by international organization. National public health services should be paid by central financial. Regional public health and local public health should be paid by provincial and local government. In additional, central government should increase input to poor province and area through transfer payment.Discussing about the health provider payment, how to pay for the different providers is the main topic in the sector. Some evidences show that if the payment is reasonable, private providers effectively provide public health services; if the payment is unreasonable, public providers also provide unnecessary public health services. Due to the different style providers exist, we have several payment ways to select. We suggest that budget payment based on health demand, government purchase and separate of revenue and expenditure.Discuss about demand payment model. We describe and explain the structure of medical insurance, the political background of CMA and progress. We think that the clinical services should be the necessary item paid by government, design payment level according to health demand. Compare to the medical insurance in urban and rural area and describe the medical insurance in other countries for exploring the future way. Finally, put forward the basic budget principle for MFA and the development.As conclusion, in the framework, we try to explore the future policy development. Firstly, we identified government as the payer. The relationship between different level governments affects the development of policy. As building public financial system, the relationship between central and local government must have some obviously changes. It is the necessary future that clears responsibility and the balance of revenue and expenditure. Secondly, from economic theory, some indexes that show the health status and coverage of primary health care had improved. But we don’t know whether the other indexes that show input also get reasonable increase or not. The policy development will focus on effective change the live of population through adjust the structure and basic direction of payment. Thirdly, there are some shortages of payment policy, such as lacking evidence for payment, but we have realized the problem. Contacting with discussion sectors, we compare different standards and ways of payment. The future policy will make more correct selection. Fourthly, the standards for government payment are not just the cost-effect ion. Political standards are another important standards. Government should be responsible for keeping the stable of society. So public health should share the financial resources with other public affair. Keeping sustainable development is another important goal for policy development.
The creation of studyDescribe the basic framework of rural public health payment policy From the new view, identify the relationship between public health payment and public financial system.Describe the policy for the future.
In other sides, as we get the support from MOH, we can invite experts to evaluate the reports and give us more valuable suggestions in the whole process. The contribution of the study lie on identifying the framework of government payment for rural public health, help select the way of payment and explore development of rural health insurance system to direct the future policy selection.The increasing medical cost is the big challenge for Chinese health system. The increasing income level of individual is much lower than increasing medical expenditure level. In 1999, the individual income had increased by 288% and 222% in city and rural area than in 1990. Compare to clinical expenditure, the increasing rate is 625%. According to the data from National Bureau of Statistics of China, every family expends 1.92% of total income to health care service. In 1999, the rate had been 3.16%, and the poorer family, the higher rate. It is more difficult to compensate the health care service only depend on user fee. The health institutes face financial constrains and for the population, it is the necessary result of increasing self medical, decreasing the utility and access of health care. The equity of health care has been threatened and health demand could not be provided.From the result of the three health care investigations, the population covered by health insurance has decreased from 30.2% to 23.6% in 1993– 1998. The lack of health insurance is more serious in rural area. In 1993, the population that enjoys the health insurance is 12.8%, but just only 9% population could accept the health insurance. Most of the people have to pay for health care services that they need. The disease burden has been increased.That data show the health payment policy have some flow back for a long time, such as the payment framework is not good enough, the responsibility of government is not clear, the criteria of payment should be proved effectively, government should pay more attention to health care service in poor. Health payment policy is one of the key points in health reform progress. The evaluation criteria, such as access of health care, equity and effective, quality of health care, poor release, have been impacted by implementation of health payment policy.
The effective health payment policy will make great contribution for the success of health reform.The essay interviewed the framework of rural health payment from 1949, analysis the reason of health payment by using economic theory, political theory, and discussing the payment relationship between different level governments, the format of provider payment, and the development of supply payment through literature review, question investigation and deeply interview.
MethodsData collection methods: literature review, deep talking with key person, question investigationsData analysis method: describing and exploring, the concept and theory of economic, investment theory, cost theory, demand theory, limited resource, stakeholder analysis, valuable analysis.Quality control: In the design and prepare period, we invited expert to discuses the topic and took the pre-investigation for making sure the feasible and science. We try to select the right individuals and groups to investigate. Making sure the valuable second-hand material that had been collected from Analysis Report of National Health Services survey, etc.
The resultsDraft the government health payment frameworks in different periods through induction of history literature and analysis the frameworks by using political theory. Make sure the development and direction of health payment policy and get the common policy characters in different time. The goal of policy is more and more clear and detail. Compare to the two goals described in different periods, we can get the conclusion. The responsibility of different level government is more and more clear. The financial decentralization had been the basic of health payment policy. Government gradually becomes the main body of health payment from 2002. Payment has become the main action to attract excellent staff. The people began explore more financial payment for health care providers from just based on institutes ability. The shortage of the original format is that the health care providers will get more financial payment through increasing beds and staff. The modern criteria are based on output of health care and utility. These changes show the development of society.Analysis the important function, policy goal, coverage of research, challenge and standard of government health payment through using the theory of rural economic, public health, health investment, equity and effective. Discuss about the relationship among health provider, health insurance, utility of health care service and government payment. Finally, we get the basic theory framework of government health payment. Interview with policy makers and operators from different province and collect some key information to learn about the key impact elements, different character and problems.In western province, the health payment need be supported by central financial and the ability of local government is limited. Health payment focused on renew of equipments, but the quality of staff and service should be improved by taking right payment way. In middle province, the interviewer hope to increase the degree of financial transfer, change the structure of health payment, strengthen the input for township hospital and other public health institutes and build the sustainable system of health payment. In east province, local governments have enough ability to pay for the rural public health, but the payment direction is not clear and the waste is serious. From these results, we can get the conclusion that the low equity and effective of government health payment is common challenge.
DiscussionsDue to the imbalance of health payment in different province, we classified the public health as four types. Global public health services (infection disease monitoring, STD and AIDS monitoring) usually are paid attention by international organization. National public health services should be paid by central financial. Regional public health and local public health should be paid by provincial and local government. In additional, central government should increase input to poor province and area through transfer payment.Discussing about the health provider payment, how to pay for the different providers is the main topic in the sector. Some evidences show that if the payment is reasonable, private providers effectively provide public health services; if the payment is unreasonable, public providers also provide unnecessary public health services. Due to the different style providers exist, we have several payment ways to select. We suggest that budget payment based on health demand, government purchase and separate of revenue and expenditure.Discuss about demand payment model. We describe and explain the structure of medical insurance, the political background of CMA and progress. We think that the clinical services should be the necessary item paid by government, design payment level according to health demand. Compare to the medical insurance in urban and rural area and describe the medical insurance in other countries for exploring the future way. Finally, put forward the basic budget principle for MFA and the development.As conclusion, in the framework, we try to explore the future policy development. Firstly, we identified government as the payer. The relationship between different level governments affects the development of policy. As building public financial system, the relationship between central and local government must have some obviously changes. It is the necessary future that clears responsibility and the balance of revenue and expenditure. Secondly, from economic theory, some indexes that show the health status and coverage of primary health care had improved. But we don’t know whether the other indexes that show input also get reasonable increase or not. The policy development will focus on effective change the live of population through adjust the structure and basic direction of payment. Thirdly, there are some shortages of payment policy, such as lacking evidence for payment, but we have realized the problem. Contacting with discussion sectors, we compare different standards and ways of payment. The future policy will make more correct selection. Fourthly, the standards for government payment are not just the cost-effect ion. Political standards are another important standards. Government should be responsible for keeping the stable of society. So public health should share the financial resources with other public affair. Keeping sustainable development is another important goal for policy development.
The creation of studyDescribe the basic framework of rural public health payment policy From the new view, identify the relationship between public health payment and public financial system.Describe the policy for the future.
2/16/2010
A Study of Preparation and Properties of Nanocomposite Coatings
Recently, nanocomposite plating technology has received increasing attention in view of the interesting possibilities that the codeposition of the nano-particles with metal phases can bring a remarkable improvement on physical and chemical properties of the coatings. In this thesis, we have investigated the preparation and property of Ni-W/SiC nanocomposite coating, Ni-W/ZrOB2 Bnanocomposite coatings and Ni-P/WC nanocomposite coating. Source from:
A Study of Preparation and Properties of Nanocomposite Coatings
A Study of Preparation and Properties of Nanocomposite Coatings
2/09/2010
Study of Sustainable Development of the Business Incubator
It is a most important way to promote the industrialization of science and technology by constructing and developing business incubators in China and most of the other countries. Business incubator plays an important role in speeding up the commercial use of scientific discoveries, cultivating the high-tech enterprises and the excellent enterprisers.
Source From: Study of Sustainable Development of the Business Incubator
Source From: Study of Sustainable Development of the Business Incubator
2/05/2010
Isolation, Detection of Enterovirus and Establishment of Quick, High-throughput EV71 Neutralization Assay
Hand-foot-mouth disease(HFMD) is popular in children,which is caused by many enteroviruses.EV71 is the main agents of HFMD in china these years.The HFMD caused by EV71 sometimes is associated with the hurt in central neural system,but there are no diagnostic reagents and effective vaccine against EV71,so the research of EV71 is very important to the development of EV71 diagnostic reagent and vaccine.In this research,we have build a platform of enterovirus isolation and identification,and a quick、high-throughput EV71 neutralizing method,we also do some basic research on the EV71 animal model.All these work will make a contribution to the research of EV71 diagnostic reagents and vaccine.In this research,we build a panel of enterovirus through virus isolation and culture,including 37 strains of EV71,9 strains of CA16 and 11 strains of non EV71＆CA16.We can do a large scale of EV71 production,concentration and purification.Now we have achieved EV71 virus with a high titer and purity.EV71 neutralization assay is important in the detection of ev71 infection.Virus isolation,RT-PCR and neutralizing test are gold criterions of EV71 indentify.The virus isolation and RT-PCR sometimes are difficult because of the virus titers are too low,so neutralization assay is a credible method to detect someone who have ever infected by EV71.In addition,the level of neutralizing antibody is important in EV71 vaccine development.The TCID_50 test is a general method now used to detect the EV71 neutralizing antibody.This method is tome-consuming,need 7 days to wait for the results.The workload is too heavy to do enough samples.The manual estimation may cause subjective error.So the TCID_50 test can not afford the quick and high-throudhput EV71 neutralization assay.In this research,we eatablished a new method for EV71 neutralization assay.This method is based on Elispot and CTL automated spot-scanning.We used a EV71 antibody marked with HRP to capture the EV71 which infected RD cells,then add TMB to make the infected cells be blue spots.We can achieve the results through the CTL automated spot-scanning apparatus.This method is quick and high-throughput, we need only 30 hours to get the results.The automated scanning is more creditable and stable then TCID_50 method.We have do some work to optimize the new EV71 neutralization assay to make it more stable.This method has a good relativity with TCID_50 method,the sensitivity,speciality and repeatability of new method is good, this research make a proof for the use and popularize of the new EV71 neutralization assay.Now,there are no good vaccine for enterovirus except the IPV and OPV for poliovirus.The EV71 vaccine development is important,the EV71 animal model is the basement of vaccine development.This research also do some experiment about the EV71 animal model.We make ICR neonatal mice as a EV71-infected model,the mice infected by EV71 show some syndromes of weigh-lost,tremble,paralysis and even death.The immunoassay of tissues show that there are EV71 in the brain of the dead mice,this basic work is useful for the later EV71 animal research and vaccine development.
The Study of Population Dynamics Behavior with Diffusion
Species dispersal and migration are one of the most prevalent phenomena of nature,and therefore become one of the most interested subjects for researchers no matter inhome and abroad. In this paper, based on the study of other authors, we give a moredepth and abroad research about the species dispersal and migration. The main contentsof this paper include: two species predator-prey Lotka-Volterra type continuous dispersalsystem with delay and Holling type II response function, two patches periodic singlespecies impulsive diffusion logistic system and two patches periodic predator-prey systemwith prey impulsive diffusion.The main contents in this paper can be summarized as follows:1. In section 1, firstly, we introduce the ecological background of this paper. Then,it is given that some research conclusion recently about continuous dispersal system andimpulsive dispersal system. We investigate our research system finally.2. In section 2, it is studied that two species predator-prey Lotka-Volterra typecontinuous dispersal system with delay and Holling type II response function. By usingcomparison theory and some analysis methods, suffcient conditions of integrable form forthe boundedness, permanence, extinction and existence of positive periodic solution areestablished, respectively.3. In section 3, we study a periodic single species logistic system with impulsivediffusion in two patches, suffcient and necessary conditions on the existence, uniquenessand global asymptotically stable of periodic solution and the extinction of species for thissystem are established by applying some analysis methods and constructing appropriateLyapunov function. Moreover, for the system with n patches, we obtained analogousresults using the same methods.4. Finally, in section 4, we study a periodic predator-prey system with prey impulsivediffusion in two patches, by using comparison theorem of impulsive differential equationand other analysis methods, suffcient and necessary conditions on the permanence and extinction of prey population for the predator-prey system with predator have other foodsource are established and, considering the predator-prey system with predator have notother food source, we show the suffcient and necessary conditions that under which thepredator population will be permanent or extinct exactly.The results show that our conclusions are perfect, and it is meaningful since there arefew studies about nonautonomous impulsive diffusion single species system and predator-prey system.
On the Dynamical Behaviors in Chemostat Model with Nutrient Recycling and Impulsive Input
Dynamical behaviors of chemostat model is an important conception with rich con-notation, which mainly includes extinction, permanence, local or global attractive, pe-riodicity and oscillation and so on. We can predict the growth rhythm and trend ofdevelopment of the chemostat through investigating the dynamical behaviors, and wecan have the optimal policy, then we can make the chemostat have the optimal growth.These will have very important theoretical and practical meaning to keep the populationdiversity and sustainable development of ecosystem. In this paper, we perform researchesof two chemostat models, which include: a chemostat model with nutrient recycling anddelays and a Monod type chemostat model with nutrient recycling and impulsive input.The main contents in this paper can be summarized as follows:1. In the first section we introduce the background, developmental process andsignificance of chemostat. Then we introduce the research results of chemostat. Finally,the organization of the paper is given.2. In the second section, a chemostat model with nutrient recycling and delays isstudied. Some conditions on the permanence and extinction of the chemostat are estab-lished and the globally asymptotically stability are obtained by constructing a Lyapunovfunction. Lastly, an example is given.3. In the third section, a Monod type chemostat model with nutrient recyclingand impulsive input is analyzed. we obtain some conditions about the extinction andpermanence of the chemostat. Then the globally asymptotically stability are obtained bycomparison theorem of impulsive di?erential equation. Lastly, an example is given.
Geochemical Fields of Metallic Deposits in West Qinling
Under the guidances of Orogenic Metallogeny, Geochemistry, and Self-Organized Criticality, and on the basis of previously basic geology, geology of mineral resources, and the data of regional geochemistry and mineral geochemistry, this paper had given a systematic state and acquired a number of results about a series of topics in west Qinling, such as composition of all geological units, metallogenic regularities, geochemical processes of ore-forming, patterns of geochemical fields of metallic deposits, geochemically metallogenic forecast models of mineral deposits, and large-middle scale of forecast models of typical ore deposits.
Source from:Geochemical Fields of Metallic Deposits in West Qinling
Source from:Geochemical Fields of Metallic Deposits in West Qinling
2/02/2010
Change in the Exchange Rate of the RMB and Employment of the Labor Force in China
The change in the exchange rate of RMB will affect many aspects of Chinese economy.What beneficial effects on economy and what effects inimical to economy has long been the focus of academic community.However,some issues are less mentioned,for instance,the relationship between change of the RMB exchange rate and employment,one of the important measures of economic development and social stability;the channels through which the change of the RMB exchange rate influence the employment;the measures China should take to stabilize the employment rate when there are changes in the RMB exchange rate.It is clear that a careful analysis of these issues will have a great practical significance for the economic development in China.Firstly,the paper introduces some related concepts of employment and exchange rate,focused on the difference between the nominal and real exchange rates,price index that impacts the calculation of real effective exchange rate,characteristics of the labor market and the present situation and major issues of labor-intensive industries in China,and reviews the academic study of the relationship between the change of exchange rate and employment and explains the research characteristics of this paper.The second chapter depicts the present situation of RMB and employment in China,and explores the correlation of change in the RMB exchange rate and fluctuations in employment.The third chapter analyzes mechanism of the impact of changes in the RMB exchange rate on the employment in China.The change in the RMB exchange rate indirectly acts on the employment mainly through foreign trade, investment and consumption.Under the same condition,RMB appreciation will cause the decline in employment through the three factors,and vice versa.According to the analysis in the previous chapters,the fourth chapter makes analysis from exchange rate changes to stimulating the economic development of our country,and then to the employment transmission mechanism.Aiming at the impact of change in the RMB exchange rate on employment,the paper sums up the main conclusions and propose policy recommendations.
The Study on BCO Service Innovation of Sino-US Shipping Line
Since April,2007,due to the subprime mortgage crisis,the lifting growth of Sino-US shipping line declines to the lowest in the past 12 years,and most shipping companies in the United States announce the trans-pacific line is caught in a deficit. To cope with the market fluctuation,it's very important for the survival of shipping companies to set up a quality customer base who has stable shipment and can bring greater gains to the line.Therefore,the high grade BCO(Beneficial Cargo Owner) become chasing target for every large container shipping company.However,most U.S.import BCO is marketing integration of large retail enterprises,and is the globalization and the combination of modern logistics philosophy.They seek carriers who are competitive,reliable,efficient,service-oriented.To be invincible in the fierce competition,container shipping companies must use the method of“service innovation”,keep for innovation and development,and improve the service. Only by this can the shipping companies keep their own benefit pattern.Therefore, the research of BCO service innovation of Sino-US shipping line is significant.The theory of this paper is service innovation,and the research method is case analysis.Firstly,it introduces the development of container transportation and the general situation of BCO service at Sino-US shipping line.Secondly,it introduces the basic theory of service innovation,review the service characteristics of BCO service,and classify the service characteristics,and form the target which influences the core competitiveness of container shipping companies.Then,it analyses the Four-dimensional degree model of BCO service innovation and also illustrate the role of each core interface element.Finally,by case analysis of the service innovation of great shipping companies,it makes suggestions to the BCO service innovation at Sino-US shipping line for the container shipping companies.This contribution of this paper is to combine with advanced service innovation theory,to make systemic analysis of the characteristics of BCO service at Sino-US shipping line,to provide valuable insights and make suggestions to the BCO service innovation.
Changes of Biochemical Properties and Freshness Evaluationin in Some Maricultured Fish-shellfishes Stored at Low Temperature_Latest Science Articles
In recent years,maricultured fisheries have developed rapidly in china,and taking the fresh or live sale as the main way can not adapt to the condition that the yield of fish and shellfishes quickly increase.It is very important to keep the freshness of the maricultured fish molluscs by iced or frozen storage.
Source from:Changes of Biochemical Properties and Freshness Evaluationin in Some Maricultured Fish-shellfishes Stored at Low Temperature_Latest Science Articles
Source from:Changes of Biochemical Properties and Freshness Evaluationin in Some Maricultured Fish-shellfishes Stored at Low Temperature_Latest Science Articles
2/01/2010
The Study of Product Differentiation and Compatibility Decisions of Firms in Network Economy_Latest Science Articles
Nowadays networks are a central issue. They connect individuals, communities, firms and structure the workings of society as a whole. Especially, in knowledge-intensive industries firms can use networks to optimize resources, response markets rapidly, share costs and realize technique innovations more efficiently. This is so-called "new economy" by Puffert and its most significant feature is network externality. Network externality, also called scale of economy of demands, means that the individual benefit from, and consequently individual willingness to pay for, consumption of the good (service) is increasing in the number of people consuming the same good (service) or a compatible one.
More please visit:The Study of Product Differentiation and Compatibility Decisions of Firms in Network Economy_Latest Science Articles
More please visit:The Study of Product Differentiation and Compatibility Decisions of Firms in Network Economy_Latest Science Articles
1/30/2010
Model Test Study on the Improved Filling Embankment in Permafrost Regions_Latest Science Articles
The results showed that improved graded structured embankment is a kind of effective structure forms to protect permafrost.1. It is studied about the styles and causes of damage of roadbed, effective measures to protect roadbed in the permafrost regions. It is thought that the key is the actions of soil, temperature and water to control the damages of roadbed, if one of the three factors is mended, the damages will be controlled and the measure can protect the permafrost.
Resource form:Model Test Study on the Improved Filling Embankment in Permafrost Regions_Latest Science Articles
Resource form:Model Test Study on the Improved Filling Embankment in Permafrost Regions_Latest Science Articles
1/29/2010
The Effect of Excessive Phosphate Fertilizer on Mineral Nutrient Uptake of Chinese Cabbage Species
Phosphorus is one of the necessary elements for plants. The available phosphorus content in the soil has been continuously increasing with the extensive application of phosphate fertilizer in China's agricultural production. The phenomenon of excessive application of phosphate fertilizer in facility agriculture is more universal. Excessive application of phosphate fertilizer is not only a waste of resources, increasing production costs, and also increase the risk of pollution of the environment. In addition, crop production, even the quality of crops and particularly the content of other nutrients and biological effectiveness will be affected in high phosphorus status. Calcium and zinc have a decisive function on human growth and metabolism. How to improve Ca and Zn contents of vegetable and absorbable Zn for human is signality to improve vegetable commodity value and further human health.A lot of phosphate fertilizers were applied in vegetable production with a negative impact on growth and nutrient uptake of vegetables. For these reasons, the growth and nutrient uptake of Chinese cabbage species were studied under excessive phosphate fertilizer by the pot experiment and field experiment, so we can explore the mechanism of mineral nutrients absorption and transportation in the plant, which was ordered to provide the basis of high yield, good quality (human health) and scientific application of phosphate fertilizer in Chinese cabbage species production. The results were as follows: The application of phosphate fertilizer significantly increased the biomass of rape and Chinese cabbage, while there was no yield response when phosphate fertilizer rate was increased.Proper amounts of phosphate and calcium fertilizers can promote the growth of rape, while it may affect the rope growth when phosphate and calcium fertilizer rate was increased.There was no significant effect on rape growth when the phosphate and zinc fertilizers were applied.The total P in rape and Chinese cabbage shoot and root was increased gradually with the increase of phosphate fertilizer rate, while the total N, K was not changed. There was a positive correlation between the concentration of total P and application of phosphate fertilizer in plant shoot and root. The total N, P, K in rape shoot and root had no significant change with the increasing of zinc. Phosphorus was absorbed luxuriously with excessive rate of phosphate fertilizer.The total Ca, Zn concentrations in rape and Chinese cabbage shoot were decreased with the increasing application rate of phosphate fertilizer. There was a negative correlation between the total P and the total Ca, Zn concentrations in rape and Chinese cabbage shoot. The total Ca in rape and Chinese cabbage root had no significant change with the excessive phosphate fertilizer. The total Ca, Zn concentrations in rape were increased respectively with the increase of calcium or zinc fertilizer rate. There was a positive correlation between the application of phosphate fertilizer and P/Ca, P/Zn in rape and Chinese cabbage shoot.There was a positive correlation between the phosphate fertilizer rate and soil Olsen-P concentration. The phosphate fertilizer rate showed no significant effect on soil available zinc, while the soil available zinc was increased with the application of zinc, and the soil available zinc was increased gradually with the increase of zinc fertilizer rate.
Effects of Biogas Residue on the Nature of Substrate and Growth of Tomato in Greenhouse
In this experiment,three compound substrates with biogas residue and Coal cinder,as well as pure biogas residue and pure coal cinder were used as substrate for greenhouse tomato cultivation.The treatments were as follows:(T1) pure coal cinder,(T2) 1 biogas residue + 3coal cinder(ⅴ/ⅴ),(T3) 1 biogas residue + 1 coal cinder,(T4) 3 biogas residue + 1 coal cinder,(T5) pure biogas residue.The experiment was taken by potted plants and the pot was 6 liter.The experiment had 5 treatments,each treatment with 5 pots,one plant each pot,and 3 replicates,and it was designed by randomized block. The physical and chemical properties,enzyme and microbiology of the substrate and the tomato plant growth and development,fruit quality and yeild were determinated.The major results were as follows:1.Biogas residue increased the value of pH and EC of substrate.In the course of plant growth, the value of pH in substrate changed differently,and the pH value of T1 and T2 increased slghly, While the pH value of T4 and T5 decreased slightly,that was the of pH value in substrates with higher content of biogas residue increased,while the pH value in substrate with higher content of coal cinder decreased during the growth of tomato plant.The main reason for the pH increasing was that:first, decomposition of biogas residue released plenty of nutrients,and the more residue biogas the more nutrients were released;second,the transpiration of tomato plants relatively increased,both of which had increased the Ca2+,Mg2+ and other ions' accumulation in substrates.The EC value of T1,T2,T3 decreased,of which the EC value of T3 was appropriate and decreased little,and the EC value of T4 and T5 increased first and decreased later,which reflected that biogas residue had characteristics of slow and long-lasting nutrient releasing.As result of containing large biogas residue,the EC value of T4 and T5 were as high as 3.14 ms·cm-1、3.39 ms·cm-1 respectively which led to a certain degree of salt accumulation It was entirely feasible to use a certain percentage of biogas residue and coal cinder as compound substrates for soilless cultivation,and T3 had the best properties,with bulk density between 0.46g·cm-3 and 0.48g·cm-3,EC value between 1.95 ms·cm-1 and 2.58 ms·cm-1x.2.Biogas residue improved the number of microorganisms in substrate.The results showed that the number of bacteria,actinomyces,fungi,cellulose-decomposing bacteria increased with the increase of the content of biogas residue in substrates;as compared with pure coal cinder substrate, substrates with biogas residue significantly increased the number of various types of microorganisms, especially improved the distribution of rhizosphere microorganisms in soilless culture substrate.Pure biogas residue treatment had a largest effect on microorganisms,which had the most number of bacteria,actinomyces,fungi,cellulose-decomposing bacteria,they were 8.40～20.85×107cfu·g-1、3.2～46.00×106cfu·g-1、26.00～62.02×104cfu·g-1、0.94～14.03×106cfu.g-1 respectively.Biogas residue promoted the proliferation of microorganisms to speed up the decomposition of organic matter and nutrients fixed to improve the effectiveness and utilization of nutrients.3.Biogas residue improved the activity of enzyme in substrate.The effects of different substrate treatments on the activity of enzyme showed that,as compared with pure coal cinder,substrates with biogas residue enhanced the activity of phosphatase,invertase,urease proteinase,cellulose significantly, in general,the activity of enzyme enhanced as the content of biogas residue increased in substrate,and the activity of invertase and urease were highest,in T5,while the activity of proteinase and cellulose were highest in T4.Substrate enzymes involved in biochemical processes in substrate,were closely related to the release and storage of nutrients,as well as the formation of humus,substrate structure and physical properties,as a result they could improve substrate activity and ability of nutrients transformation.4.Biogas residue increased tomato plant's height,stem diameter,leaf number and root activity. Tomato plants in substrates with more biogas residue had more vigorous stronger growth on height, stem diameter and leaf number.Biogas residue increased the root activity of tomato plants,highest record of root activity occurred in T4,followed by T5、T3、T2,and there were no significant differences with T4,but T4、T5、T3、T2 were significantly higher than T1 by 118%、67%、63%、20%respectively.5.Biogas residue improved tomato fruit's quality and yield.Biogas residue improved tomato fruit soluble sugar content,lowered titratable acid content,and increased the sugar/acid ratio,of which T3 was highest and reached 6.24;but biogas residue had little effects on vitamin C.Biogas residue increased tomato yield,T4 had the highest yield,followed by.T5、T3、T2,and the yield of T4,T5, T3,T2 were all significantly higher than the pure coal cinder treatment by 200%,190%,142%,129% respectively。6.In compound substrates,it is appropriate for tomato cultivation in greenhouse when the volume ratio of biogas residue is between 50%and 75%.
Energy Security and Contemporary International Relations_Latest Science Articles
The concept of energy security occurs after oil becomes the dominating energy source. Energy security mostly refers to oil security. Energy security is a traditional security conception, as well as a non-traditional security conception. The traditional characteristic means the competition for oil supply among countries, including the control and military occupancy of oil production regions.
Energy Security and Contemporary International Relations_Latest Science Articles
Energy Security and Contemporary International Relations_Latest Science Articles
1/28/2010
Research on development strategy of forestry in Shanxi Province_Latest Science Articles
The development of the forestry economy cannot be isolated from the domestic and international market. In order to study the development strategy of forestry economy, firstly we should understand the changing situation both home and abroad. Secondly, the importance of further study on international and domestic forest industry should be attached equally.
Research on development strategy of forestry in Shanxi Province_Latest Science Articles
Research on development strategy of forestry in Shanxi Province_Latest Science Articles
1/27/2010
Controllable Soft Template for the Synthesis of Gold Nanoparticles_Latest Science Articles
At present, nanotechnology is the pioneering research fields and controllable synthesis of nanoparticles with special size and morphology is one of the most important components. It is well known that nanomaterials are different from the conventional materials due to the size, morphology, and the atom ratio of surface and bulk phase of particles, etc, and are widely and significantly used in such fields as photonics, microelectronics, magnetism, catalytic properties and biology. The formation of nanostructures is a new cross-field of colloid and interface chemistry and material science and also is one of the most active research fields.
Controllable Soft Template for the Synthesis of Gold Nanoparticles_Latest Science Articles
Controllable Soft Template for the Synthesis of Gold Nanoparticles_Latest Science Articles
1/26/2010
The Research and Application of Digital Signature_Latest Science Articles
The information security has become more and more crucial with the development of computer and network technologies. The digital signature is one of key techniques in information security, especially in the authentication, data integrity, and non-repudiation. It has been widely used in military, communication, e-commerce and e-government, etc., and will become more and more popular after the e-signature law is put in practice.The main interest of this dissertation is on the theory and method of digital signature and its application.
The Research and Application of Digital Signature_Latest Science Articles
The Research and Application of Digital Signature_Latest Science Articles
1/18/2010
Study on BTDA-ODA Polyimide Nanofiber Prepared by Electrospinning
Electrospinning, a unique characteristic of easy operation, is one of best methods to make nanofibers. Electrospun membranes are able to form a large surface-to-volume ratio, highly porous mesh, highly length-diameter ratio and uniform fiber improves performance for many potential applications. For example, fabrics are suited to sorbing material and filtering material, because of their super adsorption, excellence filter capacity and good heat preservation, fabrics also be developed to fibers which have many functions such as antisepsis, radiation resistance, flame retardance and shielding. Aromatic polyimides, as a high performance functional fibers material, have marked excellent physical and chemical properties like thermal stability, dielectric property, radio resistant property, fire resistance, high strength, high modulus and nonpoisonous. The polyimide(PI) nanofiber was prepared by electrospinning the PAA solution, followed by thermal imidization and carbonisation. Imidized webs generated crosslinking and aromatic heterocyclic structures and carbonized with yields from 50% to 70%. The PI nanofiber has enormous potential value and will be a very promising precursor of carbon nanofiber.In this paper, different solid contents of BTDA-ODA Polyamic acid (PAA) solution were prepared with different solvent as DMF, DMAc and NMP. The non-woven membranes of polyimide for insulation are prepared by electrospinning the polyamic acid solution, followed by thermal imidization, carbonisation. Imidized webs were carbonized in the temperature range from 600℃to 1000℃under a nitrogen atmosphere. The images of fibers were characterized by scanning electron microscopy and transmission electron microscopy, heat-resistant quality of fibers was characterized by Thermogravimetric Analysis (TG) and phase structures were characterized by wide angle X-ray Diffraction (WAXD). The results showed that average diameter of PI nanofibers with DMF system (voltage was 15kV, receptor distance was 20cm and solid contents of solution was 25%)was the thinest from 150 to 250nm, diameter of PI nanofibers after heat treatment was from 300 to 500nm, bending, twisting and adhesion phenomenon were most serious within the fibers after imidization. however, PI non-woven membrane which prepared by PAA electrospun solution synthesized with NMP indicated a relatively high thermal stability, electrospining went again stcrystal structure of PI nanofiber, and it was little changed after heat treatment.
Development of Polyimide-based Carbon Nano-fiber Membrane
Polyimide(PI), as a kind of high-performance engineering material, possesses excellent physical and chemical properties. It has been widely used in microelectronics packaging, high temperature adhesive and composite, etc. High voltage electrospinning technology having advantages of simple technology and convenient operation.The diameters of fiber with continuitie ranged from several decade nanometer to hundreds nanometers. Polyimide-based carbonnano-fiber was prepared by high voltage electrospinning technology is of great potential value in application.This article based on structure and properties of polyimide, using pyromellitic dianhydride(PMDA) and bis(4-aminophenyl)ether(ODA) as monomer to prepare polyamide acid in N,N′-dimethylacetamide, and utilize high voltage electrospinning technology to prepare polyamic acid nano-fiber membrane which was further imidized into polyimidenano-fiber membrane, then use polyimidenano-fiber membrane as precursor to prepare polyimide-based carbonnano-fiber membrane through high-temperature carbonization process. Fiber diameter and non-woven pore size distribution were controlled by eletrospinning technological conditions. Scanning electronmicroscopy(SEM) and transmission electron microscopy (TEM) were utilized to investigate the surface morphology characteristics, Thermogravimetric analysis(TG), X-ray Diffraction (XRD) and infrared analysis(IR) were used to analysis and forecast structure.The results showed that polyimide-based carbonnano-fiber membrane possesses excellent thermal stability. SEM analysis shows that with the carbonation temperature increased, fiber diameter decreases gradually, distribution change narrowlly, mainly located between 100～200nm; when carbonization temperature reached 1000℃, Filamentous carbon content in polyimide-based carbon nano-fiber membrane is 96.16%. Fiber film start deoxy when temperature reached 600℃, and the structure of a graphite like formed temperature reached 700℃, after 700℃the combination of the heterocyclic may be produced to remove sulfur nitrogen oxide, then form continuous aromatic heterocyclic compounds, with temperature continue increased to 900℃fused ring aromatization happen, hexagonal carbon layer with graphite-like structure gradually increased.
1/06/2010
The Uniform Local Asymptyotics of the Overshoot of a Random Walk with Heavy-Tailed Increments
It is well known that much attention has been paid to issues of the uniform local asymptotics of the overshoot of a random walk with heavy-tailed increments. Asmussen et al. (2003) has got a special result of local asymptotics of the overshoot of a random walk which has some conditions of moment. Rencently, Tang (2007) has investigated the non-local asymptotics of the overshoot of a random walk. In the first chapter of this paper, we introduce some fundmential knowledge about our paper. Furthermore, we fall back a lot of results which have been got before and give the aim of our paper. In the second chapter, we obtain the uniform local asymptotics of the overshoot of a random walk with heavy-tailed increments. When the overshoot is in (x + y, x + y + T) for some 0＜T＜∞, we discuss the asymptotics for two cases about y, respectively. Firstly, y≥f(x) for any positive function f(x)→∞as x→∞; secondly, y∈[0, N] for any 0＜N＜∞. Based on above results, we discuss them further and get a result of the uniform local asymptotics of the overshoot of a random walk for the case y≥0. The obtained results require certain uniform requirements for y. At last of this paper, we give a corollary and some remarks. We illustrate that the two results of the second chapter are meaningful by the corollary, and these remarks show the direction of our further research.
Merit Function Method for Structured Monotone Variational Inequalities
This paper presents a merit function method for structured monotone variational inequalities.Numerical results illustrates the efficiency of this method.1.Since 1960s,the theory and algorithms for finite-dimensional variational inequalities developed rapidly.Variational inequalities and complementarity problems have been developed an important field in applied mathematics.They have been widely used not only in nonlinear programming but in differential equation,mechanics,cybernetics,game theory,economic equilibrium theory,social and economic model,etc.Therefore,variational inequality and its application have become a focus in mathematics.2.In Chapter 3,we constructed a merit function based the model for structured monotone variational inequalities.We transformed the original problem to an optimization problem which possesses a very simple structure for calculation in our method.At last,we gave the global convergence condition.3.In Chapter 4,we introduced some algorithms for variational problems.Some numerical examples with ball constraints or box constraints were given.Numerical results verified the validity of the method provided in chapter three.
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