Local governments have long been ardently pursuing the industrial specialization effect(MAR externalities) and industrial diversification effect(Jacobs externalities). Such a pursuit has resulted in severe distortion ...Local governments have long been ardently pursuing the industrial specialization effect(MAR externalities) and industrial diversification effect(Jacobs externalities). Such a pursuit has resulted in severe distortion of resource allocation and negative effect on sustainability of local economic development. Regarding the effect from both MAR and Jacobs externalities on local economic development existing literature records notable disputes. Therefore, for local economic development, one important issue is which externality(MAR or Jacobs) can better bring the effect into play. By studying a panel data of 283 Chinese cities from 2003 to 2012 and applying dynamic plane data GMM method, this paper conducted a regression analysis of the relationship among industrial agglomeration externalities, city size, and regional economic development. The result indicates that with regard to the whole nation, MAR externalities are conducive to regional economy development whereas Jacobs externalities will, to an extent, restrain regional economic development. As regards eastern, middle, and western regions, MAR externalities are conducive only to the economic development of the eastern region; their effects on middle and western regions are insignificant. Moreover, the interaction item between MAR externalities and city size has a significant negative synergistic effect on national economic development and a certain acceleration effect on eastern region as well as a strong negative synergistic effect on the middle region and an insignificant effect on the western region. The interaction item between Jacobs externalities and city size has a positive synergistic effect on only the middle region and has an insignificant synergistic effect on both eastern and western regions. Capital stock and labor input have significant accelerating effects on GDP growth per capita of Chinese cities, whereas material capital and labor input remain primary driving forces for Chinese local economic development. Furthermore, human capital contributes to accelerating urban economic development, whereas government intervention restrains urban economic development.展开更多
China attempts to achieve energy conservation,emission reduction and environmental protection through the implementation of the green credit policy,but its implementation impact is still controversial.An important con...China attempts to achieve energy conservation,emission reduction and environmental protection through the implementation of the green credit policy,but its implementation impact is still controversial.An important content of the green credit policy is to require banking and financial institutions to tighten the credit exposure of industries of‘high pollution and high energy consumption’and industries with overcapacity,so as to use economic leverage to curb their blind expansion and reduce energy consumption by controlling external financing.This paper examined the impact and the lingering effects of the green credit policy on external financing,economic growth and energy consumption in the manufacturing industry,which was most influenced by the green credit policy,from 2003 to 2016 by using the DID method.Furthermore,this paper estimated the dynamic endogenous relationships among external financing,economic growth and energy consumption with two-step system GMM model to investigate the influential path of the green credit policy.The results showed that:the green credit policy had a significant negative impact on the external financing of manufacturing industry,but its negative impact on the economic growth and energy consumption of manufacturing industry was not statistically significant,and the effect of the green credit policy had a dynamic feature of weakening with time.Additionally,in the manufacturing industry,there was a bilateral causal relationship between the energy consumption and economic growth of the control group industry and the processing group industry.There was a bilateral causal relationship between the economic growth and external financing of the control group industries in the manufacturing industry.There was a unilateral causal relationship between the economic growth and external financing of the processing group industries in the manufacturing industry,while the external causality existed between the control group industries and the processing group industries in the manufacturing industry.The causal relationship between the financing and energy consumption was not statistically significant.At present,the transmission path of the green credit policy is that the green credit policy controls external financing,then affects economic growth and ultimately inhibits energy consumption,but the effectiveness of the path is not statistically significant.The conclusion of this paper provides policy reference and scientific basis for the adjustment and improvement of green credit.展开更多
This paper is to provide an empirical work for agricultural spatial distribution of agriculture. We consider the spatial location pattern in order to offer spatial views on the agricultural economic research and how C...This paper is to provide an empirical work for agricultural spatial distribution of agriculture. We consider the spatial location pattern in order to offer spatial views on the agricultural economic research and how Chinese agricultural economic spatial location pattern is forming, we also tested the agglomeration situation of agriculture and the process is going on in the future. The results indicate that the periphery areas exist significant differential among regions in Hunan province, China. It really presents some kinds of agglomeration pattern of agriculture and characteristic spatial autocorrelation;the biggest rate of contribution to the region agriculture economic gap is productivity per agriculture worker.展开更多
This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughpu...This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughput as output indicators, and considering traditional(foreign trade dependence and industrialization level) and modern environmental factors(traffic line density, financial development level, and informatization level). To achieve such aim, this study constructs a multi-stage data envelopment analysis model(DEA) that identifies effective port decision-making units(DMUs) and generates a highly accurate conclusion by eliminating the interference from the exogenous environment and random errors. First, the external environment significantly affects port efficiency, with the traditional environmental factors showing huge fluctuations and the modern environmental factors producing great benefits. Second, the efficiency of ports in YRDR has increased from 2008 to 2013 primarily because of their pure technical efficiency. Third, the weighted standard deviation ellipse(SDE) analysis results reveal that the efficiency pattern of ports significantly deviates from their throughput pattern, while the center of SDE of port efficiency moves from the eastern coastal regions to the northwest regions. Based on these findings, this paper proposes spatial development strategies for YRDR, such as creating an unblocked environment where spatial elements can freely circulate, intensifying port-city joint development, implementing differentiated policies, and focusing on the spatial collaboration of port efficiency.展开更多
The 4-2-1 family structure has become many old people's choices under market economy circumstance. However,the community service for home care of elderly still has problems such as unsound service system, lack of ...The 4-2-1 family structure has become many old people's choices under market economy circumstance. However,the community service for home care of elderly still has problems such as unsound service system, lack of resources integration, and lack of human resources etc. This paper attempts to construct new mode of cooperative governance of service for home care of elderly in urban community, explore the dynamic mechanism and implementation path for service for cooperative governance of home care of elderly in urban community,point out the power of cooperative governance of community service for home care of elderly,and accomplish institutional innovation such as cultivation of collaborative culture,open power system, flat organizational structure design and group design of public policies etc.展开更多
Treating the cosmological constant as a dynamical variable,we investigate the thermodynamics and weak cosmic censorship conjecture(WCCC)of a charged AdS black hole(BH)in the Rastall gravity.We determine the energy mom...Treating the cosmological constant as a dynamical variable,we investigate the thermodynamics and weak cosmic censorship conjecture(WCCC)of a charged AdS black hole(BH)in the Rastall gravity.We determine the energy momentum relation of charged fermion at the horizon of the BH using the Dirac equation.Based on this relation,it is shown that the first law of thermodynamics still holds as a fermion is absorbed by the BH.However,the entropy of both the extremal and near-extremal BH decreases in the irreversible process,which means that the second law of thermodynamics is violated.Furthermore,we verify the validity of the WCCC by the minimum values of the metric function h(r)at its final state.For the extremal charged AdS BH in the Rastall gravity,we find that the WCCC is always valid since the BH is extreme.While for the case of near-extremal BH,we find that the WCCC could be violable in the extended phase space(EPS),depending on the value of the parameters of the BH and their variations.展开更多
The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities...The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities and production and best resources distributionproportion among the various links of security activities are presented.Moreover,itis stated that the distribution of resources law needs to be researched deeply in practicalwork to achieve optimization of safety management practice.展开更多
Tail dependence structure model based on Copula theory and extreme value theory(EVT) is constructed to picture the tail correlation of financial time series more exact.The empirical research results show that the Gumb...Tail dependence structure model based on Copula theory and extreme value theory(EVT) is constructed to picture the tail correlation of financial time series more exact.The empirical research results show that the Gumbel Copula can fit the upper and lower tail dependence structures of Shanghai A share index and Shenzhen A share index,and correlation of upper tails of both indices is stronger than that of lower-tails.展开更多
Genetically modified (GM) technology can significantly reduce pesticide use and increase yield in crop production. However, the benefit from reducing pesticide use varies substantially among farmers. The overall goal ...Genetically modified (GM) technology can significantly reduce pesticide use and increase yield in crop production. However, the benefit from reducing pesticide use varies substantially among farmers. The overall goal of this paper is to understand the relationship between farmers' knowledge of GM technology and pesticide use in genetically modified papaya (GMP) production. Based on a survey of 223 farms in three main papaya production provinces in 2010, the data show that almost all papaya planted in 2009 was genetically modified. However, only 28% of papaya farmers knew that they planted GMP, and 55% of them did not know GMP is resistant to papaya ringspot virus (PRSV). Further analyses using the general least squares (GLS) method show that farmers'knowledge of GMP significantly affects their pesticide use, and potential gain from GM technology is far below its full potential. The paper concludes with policy implications.展开更多
The kernel of interval grey number is most likely the real number,which can be used to represent whitenization value of interval grey number.A novel method for calculating kernel of interval grey number is constructed...The kernel of interval grey number is most likely the real number,which can be used to represent whitenization value of interval grey number.A novel method for calculating kernel of interval grey number is constructed based on the geometric barycenter of whitenization weight function in the two-dimensional coordinate plane,and the calculation of kernel is converted to the calculation of barycenter in geometric figures.The method fully considers the effect of all information contained in whitenization weight function on the calculation result of kernel,and is the extension and perfection of the existing methods in the scope of application.展开更多
Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an ...Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an interval-parameter fuzzy robust nonlinear programming (IFRNP) model was developed for water quality management to deal with such difficulties. The developed model incorporated interval nonlinear programming (INP) and fuzzy robust programming (FRP) methods within a general optimization framework. The developed IFRNP model not only could explicitly deal with uncertainties represented as discrete interval numbers and fuzzy membership functions, but also was able to deal with nonlinearities in the objective function.展开更多
Owing to the radical changing of Chinese economy, it is essential to build an effective financial distress prediction model. In this paper, we present a genetic algorithm (GA) approach for optimizing parameters of sup...Owing to the radical changing of Chinese economy, it is essential to build an effective financial distress prediction model. In this paper, we present a genetic algorithm (GA) approach for optimizing parameters of support vector machine (SVM). We validate the proposed model on datasets of Chinese high-tech manufacturing industry. Experimental results reveal that the proposed GA-SVM model can compare to and even outperform other exiting classifiers. Compared to grid-search algorithm, the proposed GA-based takes less time to optimize SVM parameter without degrading the prediction accuracy of SVM.展开更多
Modeling approach using discrete event simulation has been proven to work well in modeling in health care. The aim of our paper is to propose a simulation approach which shows realistic models presenting different pos...Modeling approach using discrete event simulation has been proven to work well in modeling in health care. The aim of our paper is to propose a simulation approach which shows realistic models presenting different possible treatments in different stages of diabetic retinopathy. We have presented three models in order to choose the best treatment for diabetic retinopathy patients. The first model describes the flow of a patient through stages without any medical treatments. It takes 13 years to reach blindness. The second model which includes the laser photocoagulation treatments leads to blindness after 46 years. Then, the third model illustrates the involvement of vitrectomy operation and delays blindness by 23 years. To construct the models, data were taken from experienced doctors and professors of the ophthalmology department in the University hospital Habib Bourguiba and the endocrinology department in the University hospital Hedi Chaker in Sfax, Tunisia. Our objective is to delay reaching the blindness stage as late as possible. Three models were developed, verified and validated through many iterative implementations with ARENA simulation software.展开更多
The tool system of the organizational risk analyzer (ORA) to study the network of East Turkistan terrorists is selected. The model of the relationships among its personnel, knowledge, resources and task entities is re...The tool system of the organizational risk analyzer (ORA) to study the network of East Turkistan terrorists is selected. The model of the relationships among its personnel, knowledge, resources and task entities is represented by the meta-matrix in ORA, with which to analyze the risks and vulnerabilities of organizational structure quantitatively, and obtain the last vulnerabilities and risks of the organization. Case study in this system shows that it should be a shortcut to destroy effectively the network of terrorists by recognizing the caucus persons of the terrorism organization for the first and eliminating them when strikes the terror organization. It is vital to ensure effective use of the resources and control the risks of terrorist attacks.展开更多
The first law of black hole thermodynamics has been shown to be valid in the extended phase space.However,the second law and the weak cosmic censorship conjecture have not been investigated extensively.We investigate ...The first law of black hole thermodynamics has been shown to be valid in the extended phase space.However,the second law and the weak cosmic censorship conjecture have not been investigated extensively.We investigate the laws of thermodynamics and the weak cosmic censorship conjecture of an AdS black hole with a global monopole in the extended phase space in the case of charged particle absorption.It is shown that the first law of thermodynamics is valid,while the second law is violated for the extremal and near-extremal black holes.Moreover,we find that the weak cosmic censorship conjecture is valid only for the extremal black hole,and that it can be violated for the near-extremal black holes,which is different from the previous results.展开更多
The Lewisian turning-point obviously increase the labor costs of Chinese manufacturing firms,it made the employee turnover to become the key problem that how to keep the enterprise human resource stability.Here,the co...The Lewisian turning-point obviously increase the labor costs of Chinese manufacturing firms,it made the employee turnover to become the key problem that how to keep the enterprise human resource stability.Here,the conceptual catastrophe model of employee turnover is built from the new perspective of empirical study and catastrophe theory.In particular,we developed a parameter estimation method of the Cusp catastrophe model based on qualitative simulation and fuzzy math,and then to demonstrate the rationality and robustness of this method by a practical case on a manufacturing enterprise.In the end,a series of virtual experiments are carried out for the employee turnover in the period of China’s economic transformation.The main results are that,how to measure the warning,critical and mutation area of employee turnover;the real relationship between the complex economic environment and the demission of employees;the control policy from the macroscopic governmental measures and microscopic enterprise ways.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41571112)Natural Science Foundation of Zhejiang Province of China(No.LY16D010002)
文摘Local governments have long been ardently pursuing the industrial specialization effect(MAR externalities) and industrial diversification effect(Jacobs externalities). Such a pursuit has resulted in severe distortion of resource allocation and negative effect on sustainability of local economic development. Regarding the effect from both MAR and Jacobs externalities on local economic development existing literature records notable disputes. Therefore, for local economic development, one important issue is which externality(MAR or Jacobs) can better bring the effect into play. By studying a panel data of 283 Chinese cities from 2003 to 2012 and applying dynamic plane data GMM method, this paper conducted a regression analysis of the relationship among industrial agglomeration externalities, city size, and regional economic development. The result indicates that with regard to the whole nation, MAR externalities are conducive to regional economy development whereas Jacobs externalities will, to an extent, restrain regional economic development. As regards eastern, middle, and western regions, MAR externalities are conducive only to the economic development of the eastern region; their effects on middle and western regions are insignificant. Moreover, the interaction item between MAR externalities and city size has a significant negative synergistic effect on national economic development and a certain acceleration effect on eastern region as well as a strong negative synergistic effect on the middle region and an insignificant effect on the western region. The interaction item between Jacobs externalities and city size has a positive synergistic effect on only the middle region and has an insignificant synergistic effect on both eastern and western regions. Capital stock and labor input have significant accelerating effects on GDP growth per capita of Chinese cities, whereas material capital and labor input remain primary driving forces for Chinese local economic development. Furthermore, human capital contributes to accelerating urban economic development, whereas government intervention restrains urban economic development.
文摘China attempts to achieve energy conservation,emission reduction and environmental protection through the implementation of the green credit policy,but its implementation impact is still controversial.An important content of the green credit policy is to require banking and financial institutions to tighten the credit exposure of industries of‘high pollution and high energy consumption’and industries with overcapacity,so as to use economic leverage to curb their blind expansion and reduce energy consumption by controlling external financing.This paper examined the impact and the lingering effects of the green credit policy on external financing,economic growth and energy consumption in the manufacturing industry,which was most influenced by the green credit policy,from 2003 to 2016 by using the DID method.Furthermore,this paper estimated the dynamic endogenous relationships among external financing,economic growth and energy consumption with two-step system GMM model to investigate the influential path of the green credit policy.The results showed that:the green credit policy had a significant negative impact on the external financing of manufacturing industry,but its negative impact on the economic growth and energy consumption of manufacturing industry was not statistically significant,and the effect of the green credit policy had a dynamic feature of weakening with time.Additionally,in the manufacturing industry,there was a bilateral causal relationship between the energy consumption and economic growth of the control group industry and the processing group industry.There was a bilateral causal relationship between the economic growth and external financing of the control group industries in the manufacturing industry.There was a unilateral causal relationship between the economic growth and external financing of the processing group industries in the manufacturing industry,while the external causality existed between the control group industries and the processing group industries in the manufacturing industry.The causal relationship between the financing and energy consumption was not statistically significant.At present,the transmission path of the green credit policy is that the green credit policy controls external financing,then affects economic growth and ultimately inhibits energy consumption,but the effectiveness of the path is not statistically significant.The conclusion of this paper provides policy reference and scientific basis for the adjustment and improvement of green credit.
文摘This paper is to provide an empirical work for agricultural spatial distribution of agriculture. We consider the spatial location pattern in order to offer spatial views on the agricultural economic research and how Chinese agricultural economic spatial location pattern is forming, we also tested the agglomeration situation of agriculture and the process is going on in the future. The results indicate that the periphery areas exist significant differential among regions in Hunan province, China. It really presents some kinds of agglomeration pattern of agriculture and characteristic spatial autocorrelation;the biggest rate of contribution to the region agriculture economic gap is productivity per agriculture worker.
基金Under the auspices of National Natural Science Foundation of China(No.41271136,41501142)
文摘This paper measures the efficiency of ports in the Yangtze River Delta Region(YRDR) in 2008 and 2013 using port berth quantity, quay length, and human resources as input indicators, using cargo and container throughput as output indicators, and considering traditional(foreign trade dependence and industrialization level) and modern environmental factors(traffic line density, financial development level, and informatization level). To achieve such aim, this study constructs a multi-stage data envelopment analysis model(DEA) that identifies effective port decision-making units(DMUs) and generates a highly accurate conclusion by eliminating the interference from the exogenous environment and random errors. First, the external environment significantly affects port efficiency, with the traditional environmental factors showing huge fluctuations and the modern environmental factors producing great benefits. Second, the efficiency of ports in YRDR has increased from 2008 to 2013 primarily because of their pure technical efficiency. Third, the weighted standard deviation ellipse(SDE) analysis results reveal that the efficiency pattern of ports significantly deviates from their throughput pattern, while the center of SDE of port efficiency moves from the eastern coastal regions to the northwest regions. Based on these findings, this paper proposes spatial development strategies for YRDR, such as creating an unblocked environment where spatial elements can freely circulate, intensifying port-city joint development, implementing differentiated policies, and focusing on the spatial collaboration of port efficiency.
基金research results for the project supported by National Social Science Foundation-“Study on the Revolution of Urban-rural Relationship in Sichuan and Chongqing Area Since new China was founded”(Project No.:12xzs016)the topic of“Research center of Social Development and Social Risk Control”by Sichuan Chief Research Base of Philosophy and Sociology-“Study on Performance Evaluation and Operation Mode of Community Service for Home Care of Elderly in Sichuan”(Project No.:SR15A13)
文摘The 4-2-1 family structure has become many old people's choices under market economy circumstance. However,the community service for home care of elderly still has problems such as unsound service system, lack of resources integration, and lack of human resources etc. This paper attempts to construct new mode of cooperative governance of service for home care of elderly in urban community, explore the dynamic mechanism and implementation path for service for cooperative governance of home care of elderly in urban community,point out the power of cooperative governance of community service for home care of elderly,and accomplish institutional innovation such as cultivation of collaborative culture,open power system, flat organizational structure design and group design of public policies etc.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11875095 and 11903025)the Basic Research Project of Science and Technology Committee of Chongqing(Grant No.cstc2018jcyjA2480)the Fundamental Research Funds of ChinaWest Normal University(Grant No.18Q062).
文摘Treating the cosmological constant as a dynamical variable,we investigate the thermodynamics and weak cosmic censorship conjecture(WCCC)of a charged AdS black hole(BH)in the Rastall gravity.We determine the energy momentum relation of charged fermion at the horizon of the BH using the Dirac equation.Based on this relation,it is shown that the first law of thermodynamics still holds as a fermion is absorbed by the BH.However,the entropy of both the extremal and near-extremal BH decreases in the irreversible process,which means that the second law of thermodynamics is violated.Furthermore,we verify the validity of the WCCC by the minimum values of the metric function h(r)at its final state.For the extremal charged AdS BH in the Rastall gravity,we find that the WCCC is always valid since the BH is extreme.While for the case of near-extremal BH,we find that the WCCC could be violable in the extended phase space(EPS),depending on the value of the parameters of the BH and their variations.
文摘The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities and production and best resources distributionproportion among the various links of security activities are presented.Moreover,itis stated that the distribution of resources law needs to be researched deeply in practicalwork to achieve optimization of safety management practice.
基金The National Natural Science Foundation of China (No70331001)
文摘Tail dependence structure model based on Copula theory and extreme value theory(EVT) is constructed to picture the tail correlation of financial time series more exact.The empirical research results show that the Gumbel Copula can fit the upper and lower tail dependence structures of Shanghai A share index and Shenzhen A share index,and correlation of upper tails of both indices is stronger than that of lower-tails.
基金supported by the the National Key Program on Genetically Modified New Varieties ,China(2011ZX08015-002)the International Development Research Center(106100-001)
文摘Genetically modified (GM) technology can significantly reduce pesticide use and increase yield in crop production. However, the benefit from reducing pesticide use varies substantially among farmers. The overall goal of this paper is to understand the relationship between farmers' knowledge of GM technology and pesticide use in genetically modified papaya (GMP) production. Based on a survey of 223 farms in three main papaya production provinces in 2010, the data show that almost all papaya planted in 2009 was genetically modified. However, only 28% of papaya farmers knew that they planted GMP, and 55% of them did not know GMP is resistant to papaya ringspot virus (PRSV). Further analyses using the general least squares (GLS) method show that farmers'knowledge of GMP significantly affects their pesticide use, and potential gain from GM technology is far below its full potential. The paper concludes with policy implications.
基金Supported by the National Natural Science Foundation of China(71271226,70971064,71101159)the Humanities and Social Science Foundation of Ministry of Education(11YJC630273,12YJC630140)+4 种基金the Program for Chongqing Innovation Team in University(KJTD201313)the Science and Technology Research Projects of Chongqing Education Commission(KJ120706)the Open Foundation of Chongqing Key Laboratory of Electronic Commerce and Supply Chain System(2012ECSC0101)the Special Fund of Chongqing Key Laboratory of Electronic Commerce and Supply Chain System(2012ECSC0217)the Chongqing City Board of Education Science and Technology Research Projects(1202010)
文摘The kernel of interval grey number is most likely the real number,which can be used to represent whitenization value of interval grey number.A novel method for calculating kernel of interval grey number is constructed based on the geometric barycenter of whitenization weight function in the two-dimensional coordinate plane,and the calculation of kernel is converted to the calculation of barycenter in geometric figures.The method fully considers the effect of all information contained in whitenization weight function on the calculation result of kernel,and is the extension and perfection of the existing methods in the scope of application.
文摘Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an interval-parameter fuzzy robust nonlinear programming (IFRNP) model was developed for water quality management to deal with such difficulties. The developed model incorporated interval nonlinear programming (INP) and fuzzy robust programming (FRP) methods within a general optimization framework. The developed IFRNP model not only could explicitly deal with uncertainties represented as discrete interval numbers and fuzzy membership functions, but also was able to deal with nonlinearities in the objective function.
基金Supported by the Cultivation Fund of the Key Scientific and Technical Innovation Project from Ministry of Education of China ( No.706024)the International Science Cooperation Foundation of Shanghai (No.061307041)the Excellent Youth Foundation ofShanghai (No.07A212)
文摘Owing to the radical changing of Chinese economy, it is essential to build an effective financial distress prediction model. In this paper, we present a genetic algorithm (GA) approach for optimizing parameters of support vector machine (SVM). We validate the proposed model on datasets of Chinese high-tech manufacturing industry. Experimental results reveal that the proposed GA-SVM model can compare to and even outperform other exiting classifiers. Compared to grid-search algorithm, the proposed GA-based takes less time to optimize SVM parameter without degrading the prediction accuracy of SVM.
文摘Modeling approach using discrete event simulation has been proven to work well in modeling in health care. The aim of our paper is to propose a simulation approach which shows realistic models presenting different possible treatments in different stages of diabetic retinopathy. We have presented three models in order to choose the best treatment for diabetic retinopathy patients. The first model describes the flow of a patient through stages without any medical treatments. It takes 13 years to reach blindness. The second model which includes the laser photocoagulation treatments leads to blindness after 46 years. Then, the third model illustrates the involvement of vitrectomy operation and delays blindness by 23 years. To construct the models, data were taken from experienced doctors and professors of the ophthalmology department in the University hospital Habib Bourguiba and the endocrinology department in the University hospital Hedi Chaker in Sfax, Tunisia. Our objective is to delay reaching the blindness stage as late as possible. Three models were developed, verified and validated through many iterative implementations with ARENA simulation software.
文摘The tool system of the organizational risk analyzer (ORA) to study the network of East Turkistan terrorists is selected. The model of the relationships among its personnel, knowledge, resources and task entities is represented by the meta-matrix in ORA, with which to analyze the risks and vulnerabilities of organizational structure quantitatively, and obtain the last vulnerabilities and risks of the organization. Case study in this system shows that it should be a shortcut to destroy effectively the network of terrorists by recognizing the caucus persons of the terrorism organization for the first and eliminating them when strikes the terror organization. It is vital to ensure effective use of the resources and control the risks of terrorist attacks.
基金Supported by National Natural Science Foundation of China(11875095)Basic Research Project of Science and Technology Committee of Chongqing(cstc2018jcyjA2480)。
文摘The first law of black hole thermodynamics has been shown to be valid in the extended phase space.However,the second law and the weak cosmic censorship conjecture have not been investigated extensively.We investigate the laws of thermodynamics and the weak cosmic censorship conjecture of an AdS black hole with a global monopole in the extended phase space in the case of charged particle absorption.It is shown that the first law of thermodynamics is valid,while the second law is violated for the extremal and near-extremal black holes.Moreover,we find that the weak cosmic censorship conjecture is valid only for the extremal black hole,and that it can be violated for the near-extremal black holes,which is different from the previous results.
基金supported by China National Nature Science Foundation(Grant No.71271093).
文摘The Lewisian turning-point obviously increase the labor costs of Chinese manufacturing firms,it made the employee turnover to become the key problem that how to keep the enterprise human resource stability.Here,the conceptual catastrophe model of employee turnover is built from the new perspective of empirical study and catastrophe theory.In particular,we developed a parameter estimation method of the Cusp catastrophe model based on qualitative simulation and fuzzy math,and then to demonstrate the rationality and robustness of this method by a practical case on a manufacturing enterprise.In the end,a series of virtual experiments are carried out for the employee turnover in the period of China’s economic transformation.The main results are that,how to measure the warning,critical and mutation area of employee turnover;the real relationship between the complex economic environment and the demission of employees;the control policy from the macroscopic governmental measures and microscopic enterprise ways.