AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 decades.METHODS:The literature search was performed on the Web of Science and included PIOLs studies p...AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 decades.METHODS:The literature search was performed on the Web of Science and included PIOLs studies published between January 2000 and December 2022.The retrieved literature was collated and analyzed by R-tool’s Bibliometrix package,CitNetExplorer,CiteSpace and other software.RESULTS:A total of 1801 articles about PIOLs were obtained,most of which were published in Spain and the United States.The organization that published the most articles was the University of Valencia in Spain.Alió JL,and Montés-Micó R,from Spain were the most influential authors in this field.The Journal of Cataract and Refractive Surgery and Journal of Refractive Surgery were the core journals for this field;the top 10 cited articles mainly focus on postoperative satisfaction with multifocal intraocular lens(IOLs)and postoperative results of toric IOLs.Through the keyword analysis,we found that trifocal IOLs,astigmatism and extended depth of focus(EDoF)IOLs are the most discussed topics at present,and the importance of astigmatism and the clinical application of the new generation of PIOLs are the emerging research trends.CONCLUSION:Bibliometric analysis can effectively help to identify multilevel concerns in PIOLs research and the prevailing research trends in the realm of PIOLs encompass the adoption of EDoF IOLs,trifocal IOLs,and their respective Toric models.展开更多
The performance characteristics,particularly the starting performance of direct line-fed induction motors,which are mainly influenced by the design of the rotor,are crucial considerations for end-users.It is quite a c...The performance characteristics,particularly the starting performance of direct line-fed induction motors,which are mainly influenced by the design of the rotor,are crucial considerations for end-users.It is quite a challenging issue for motor manufacturers to enhance the starting performance of existing mass-produced motors with minimal modifications and expenses.In this paper,a simple and cost-effective method to improve the starting performance of a commercial squirrel-cage induction motor(SCIM)is proposed.The influence of geometric parameters of the end-ring on the performance characteristics,including starting(locked rotor)torque,pull-up and break down torque,starting current,rotor electric parameters,current density,power losses,and efficiency have been comprehensively investigated.It has been revealed that among the other end-ring design parameters,the ring thickness has a significant effect on the performance characteristics.An optimal end-ring thickness is determined,and its performance characteristics have been compared to those of its initial counterpart.Numeric and parametric analyses have been conducted using a 2D time-stepping finite element method(FEM).The FEM results were validated using experimental measurements obtained from an 11 kW SCIM prototype.展开更多
Data is a key asset for digital platforms,and mergers and acquisitions(M&As)are an important way for platform enterprises to acquire it.The types of data obtained from intra-industry and cross-sector M&As diff...Data is a key asset for digital platforms,and mergers and acquisitions(M&As)are an important way for platform enterprises to acquire it.The types of data obtained from intra-industry and cross-sector M&As differ,as does the extent to which they interact within or between platforms.The impact of such data on corporate market performance is an important question to consider when selecting strategies for digital platform M&As.Based on our research on advertising-driven platforms,we developed a two-stage Hotelling game model for comparing the market performance effects of intra-industry M&As and cross-sector M&As for digital platforms.We carried out an empirical test using relevant data from advertising-driven digital platforms between 2009 and 2021,as well as a case study on Baidu’s M&A activities.Our research discovered that intra-industry M&As driven by“data economies of scale”and cross-sector M&As driven by“data economies of scope”are both beneficial to the market performance of platform enterprises.Intra-industry M&As have a more significant positive effect on the market performance of platform enterprises because the same types of data are easier to integrate and develop the“network effect of data scale”.From a data factor perspective,this paper reveals the inherent economic logic by which different types of M&As influence the market performance of digital platforms,as well as policymaking recommendations for all digital platforms to select M&A strategies based on data scale,data scope,and the network effect of data.展开更多
Crop insurance in China is currently adopting the premium pricing strategy of "One Province One Rate", which appears to be in line with the systematic risk characteristics within crop insurance. This researc...Crop insurance in China is currently adopting the premium pricing strategy of "One Province One Rate", which appears to be in line with the systematic risk characteristics within crop insurance. This research aims to investigate the theoretical rationalization of this pricing strategy and its implications using the spatial lag model and the county-level data from the 45 corn plant counties of Jilin Province, China. Results corroborate that:(1) the spatial spillover effect of the corn yield risk is significant in Jilin but decreases rapidly when the risk unit includes more than eight counties; and(2) separating Jilin Province into eight risk zones for corn insurance will significantly reduce the high cross-subsidy phenomenon arising from the "One Province One Rate" strategy and shall benefit poor peasants in the region as well. This paper not only proves the existence of a systematic risk of crop insurance but also reveals that the spatial correlation and systemic features of the crop yield risk do not create a solid foundation for the current pricing strategy of "One Province One Rate". These conclusions will undoubtedly provide important references and empirical evidence for the role of China’s crop insurance in poverty alleviation.展开更多
We consider a risk model with a premium rate which varies with the level of free reserves. In this model, the occurrence of claims is described by a Cox process with Markov intensity process, and the influence of stoc...We consider a risk model with a premium rate which varies with the level of free reserves. In this model, the occurrence of claims is described by a Cox process with Markov intensity process, and the influence of stochastic factors is considered by adding a diffusion process. The integro-differential equation for the ruin probability is derived by a infinitesimal method. Key words ruin probability - variable premium rate - diffusion process - Markov intensity CLC number O 211.9 Foundation item: Supported by the National Natural Science Foundation of China (10071058, 70273029)展开更多
By analyzing the cause of too high premium rate of pension insurance at present and discussing the current practice of Chinese Pension Insurance System, three models to determine the reasonable paying level of premium...By analyzing the cause of too high premium rate of pension insurance at present and discussing the current practice of Chinese Pension Insurance System, three models to determine the reasonable paying level of premium, returning level of retirement pay and premium rate are established. Comparatively speaking, these models solve the problem of the determination of the premium rate more scientifically and offer an effective analyzing means to the improvement of the Chinese Pension Insurance System.展开更多
This paper concerns an optimal dividend-penalty problem for the risk models with surplus-dependent premiums.The objective is to maximize the difference of the expected cumulative discounted dividend payments received ...This paper concerns an optimal dividend-penalty problem for the risk models with surplus-dependent premiums.The objective is to maximize the difference of the expected cumulative discounted dividend payments received until the moment of ruin and a discounted penalty payment taken at the moment of ruin.Since the value function may be not smooth enough to be the classical solution of the HJB equation,the viscosity solution is involved.The optimal value function can be characterized as the smallest viscosity supersolution of the HJB equation and the optimal dividend-penalty strategy has a band structure.Finally,some numerical examples with gamma distribution for the claims are analyzed.展开更多
In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term ...In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain.展开更多
A differential fatherhood premium exists among selected groups of fathers of various socio-economic backgrounds. Besides marital status, residential arrangement, biological paternity, and other demographic dimensions,...A differential fatherhood premium exists among selected groups of fathers of various socio-economic backgrounds. Besides marital status, residential arrangement, biological paternity, and other demographic dimensions, the mechanisms associated with fathers' structural characteristics of work that produce divergent labor market outcomes are less well understood. The authors leveraged the cases of productivity and specialization, family and responsibility, and compensating differentials and examined the impacts of work context and occupational characteristics on the pay gap between fathers and non-fathers Based on joint data from the 1997-2015 National Longitudinal Survey of Youth (NLSY97) and Occupational Information Network (O'NET) (n -- 37,138), the authors used fixed-effects models to estimate the associations between job features and the fatherhood premium. The regression results showed that occupations entailing competition and requiring on-the-job training are associated with more wage bonus; occupations offering inflexible schedule are associated with less wage gain These work-related characteristics further emphasize fathers' work structure and context, human capital accumulation, and work-family conflict. Overall, these findings are consistent with the theoretical perspectives of productivity and specialization and compensating differentials, adding new evidences to the structural explanations of the fatherhood premium.展开更多
First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continu...First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continuous promotion of agricultural insurance,increase in the types of agricultural insurance and increase in the number of the insured,the premium rate should also be adjusted opportunely.Then,on the basis of Bayes' theorem,I adjust and calibrate the claim frequency and the average claim,in order to correctly adjust agricultural insurance premium rate;take the case of forest insurance for premium rate adjustment analysis.In setting and adjustment of agricultural insurance premium rate,in order to make the expected results well close to the real results,it is necessary to apply the probability estimates in a large number of risk units;focus on the establishment of agricultural risk database,to timely adjust agricultural insurance premium rate.展开更多
Let u ∈ R ,for any ω 〉 0, the processes X^ε = {X^ε(t); 0 ≤ t≤ 1} are governed by the following random evolution equations dX^ε(t)= b(X^ε(t),v(t))dt-εdSt/ε, where S={St; 0≤t≤1} is a compound Pois...Let u ∈ R ,for any ω 〉 0, the processes X^ε = {X^ε(t); 0 ≤ t≤ 1} are governed by the following random evolution equations dX^ε(t)= b(X^ε(t),v(t))dt-εdSt/ε, where S={St; 0≤t≤1} is a compound Poisson process, the process v={v(t); 0≤t≤1} is independent of S and takes values in R^m. We derive the large deviation principle for{(X^ε,v(.)); ε〉0} when ε↓0 by approximation method and contraction principle, which will be meaningful for us to find out the path property for the risk process of this type.展开更多
Based on theoretical analysis of crop risk and premium rate setting,we take the case of premium rate setting of insurance on cotton yield in Shache County,Shaya County and Aksu City of Xinjiang.Using parametric method...Based on theoretical analysis of crop risk and premium rate setting,we take the case of premium rate setting of insurance on cotton yield in Shache County,Shaya County and Aksu City of Xinjiang.Using parametric methods and insurance actuarial technique,we select the optimal model for risk fitting of cotton yield in three areas;compare the premium rate calculated accurately under four risk distribution assumptions of cotton yield,and the rational premium rate,to analyze the impact of risk distribution of crop yield on premium rate setting.The empirical results show that the Logistic distribution is the optimal distribution for risk fitting of cotton yield in three areas;the rational net premium rate of cotton insurance in three areas is 7.62%,6.32% and 4.96%,respectively;there are errors in premium rate setting under assumptions of normal distribution,normalized skew distribution and Weibull distribution,ranging from 0.2 percentage points to 8 percentage points.Thus,it indicates that the selection of risk distribution model of yield directly affects the accuracy of premium rate setting of crops,and the key to accurate premium rate setting of crops lies in correct selection of risk distribution model of yield.展开更多
Premium thread connection tubing and casing products are non-API products that are used in severe oil field conditions, such as deep wells ,ultra deep wells, high pressure gas wells, horizontal wells and steam injecti...Premium thread connection tubing and casing products are non-API products that are used in severe oil field conditions, such as deep wells ,ultra deep wells, high pressure gas wells, horizontal wells and steam injection wells, etc. In order to meet the requirements of oilfields for premium thread connection oil country tubular goods ( OCTG), Baosteel developed its own series of premium thread connection tubing and casing products that are protected by intellectual property rights. This study introduces the process of developing the premium thread connection tubing and casing products, their characteristics, and their actual application in oil fields. It hopes to give customers a better understanding of Premium thread connection tubing and casing products from Baosteel.展开更多
In this paper, we propose a new risk measure which is based on the Or- licz premium principle to characterize catastrophe risk premium. The intention is to develop a formulation strategy for Catastrophe Fund. The loga...In this paper, we propose a new risk measure which is based on the Or- licz premium principle to characterize catastrophe risk premium. The intention is to develop a formulation strategy for Catastrophe Fund. The logarithm equivalent form of reinsurance premium is regarded as the retention of reinsurer, and the differential earnings between the reinsurance premium and the reinsurer's retention is accumu- lated as a part of Catastrophe Fund. We demonstrate that the aforementioned risk measure has some good properties, which are further confirmed by numerical simu- lations in R environment.展开更多
Volatility is an important variable in the financial market. We propose a model-free implied volatility method to measure the volatility and test the volatility risk premium. The model-free implied volatility does not...Volatility is an important variable in the financial market. We propose a model-free implied volatility method to measure the volatility and test the volatility risk premium. The model-free implied volatility does not depend on the option pricing model, and extracts information from all the option contracts. We provide empirical evidence from the S & P 500 index option that model-free implied volatility is more accurate to forecast the future volatility and the volatility risk premium does not exist.展开更多
We study the sample of 311 non-outstanding shares transfers from 2003 to 2004. The object of this study is to determine the extent to which premium can be explained by financial factors of firms. The intrinsic value o...We study the sample of 311 non-outstanding shares transfers from 2003 to 2004. The object of this study is to determine the extent to which premium can be explained by financial factors of firms. The intrinsic value of transferred shares with control right is different from the others. We find that the larger percent of share transferred, the higher premium will be paid. Current liability ratio interpreting the premium of non-outstanding shares transfers is negative related to short term debt. Price ratio can determine the premium level when the ratio of transfer share under 30 percent展开更多
To participate in social insurance is a major social responsibility of enterprises, even it is a mandatory social policy, companies still escaped pay society insurance. The serious consequences of this phenomenon beco...To participate in social insurance is a major social responsibility of enterprises, even it is a mandatory social policy, companies still escaped pay society insurance. The serious consequences of this phenomenon become increasingly prominent.it not only damaged the justice of labor market, but also violated the staffs interest. Various factors influence enterprise to participate in social insurance behavior .Human capital is the impact of insurance companies. This paper is mainly focusing on the theory analysis of different human capital participating behavior of enterprises. From the perspective of human capital, using the cost-benefit theory and rational choice theory in economics to explore participating behavior, enterprise employees of different human capital differences in attitude to attend social insurance. No matter enterprises with higher or lower human capital, enterprises and employees choose to participate in social insurance act consistently. But, it can improve participate of low human capital enterprise behavior when payment rate reduced. So, it is suggested that establishing a lower level of social insurance system is helpful to expand coverage, it can through e^tahllgh the sunnlementarv insurance system meet the needs of more people.展开更多
Matrox3月27日宣布Matrox Rt.X2系列编辑平台30版驱动程序将支持最新推出的Adobe Creative Suite 3 Production Premiumg 和Adobe Premiere ProCS3软件。除此以外.MatroxRT×230版驱动程序还将提供对WindowsVqsta的支持、支持更多...Matrox3月27日宣布Matrox Rt.X2系列编辑平台30版驱动程序将支持最新推出的Adobe Creative Suite 3 Production Premiumg 和Adobe Premiere ProCS3软件。除此以外.MatroxRT×230版驱动程序还将提供对WindowsVqsta的支持、支持更多高清和标清摄像机及编辑分辨率.再加上新的实时特技。展开更多
基金Supported by the National Natural Science Foundation of China(No.82371033No.81970772)+1 种基金the Tianjin Natural Science Foundation(No.21JCZDJC01250)the Tianjin Key Medical Discipline(Specialty)Construction Project(No.TJYXZDXK-016A).
文摘AIM:To analysis of research hotspots and trends on the application of premium intraocular lens(PIOLs)in the past 2 decades.METHODS:The literature search was performed on the Web of Science and included PIOLs studies published between January 2000 and December 2022.The retrieved literature was collated and analyzed by R-tool’s Bibliometrix package,CitNetExplorer,CiteSpace and other software.RESULTS:A total of 1801 articles about PIOLs were obtained,most of which were published in Spain and the United States.The organization that published the most articles was the University of Valencia in Spain.Alió JL,and Montés-Micó R,from Spain were the most influential authors in this field.The Journal of Cataract and Refractive Surgery and Journal of Refractive Surgery were the core journals for this field;the top 10 cited articles mainly focus on postoperative satisfaction with multifocal intraocular lens(IOLs)and postoperative results of toric IOLs.Through the keyword analysis,we found that trifocal IOLs,astigmatism and extended depth of focus(EDoF)IOLs are the most discussed topics at present,and the importance of astigmatism and the clinical application of the new generation of PIOLs are the emerging research trends.CONCLUSION:Bibliometric analysis can effectively help to identify multilevel concerns in PIOLs research and the prevailing research trends in the realm of PIOLs encompass the adoption of EDoF IOLs,trifocal IOLs,and their respective Toric models.
文摘The performance characteristics,particularly the starting performance of direct line-fed induction motors,which are mainly influenced by the design of the rotor,are crucial considerations for end-users.It is quite a challenging issue for motor manufacturers to enhance the starting performance of existing mass-produced motors with minimal modifications and expenses.In this paper,a simple and cost-effective method to improve the starting performance of a commercial squirrel-cage induction motor(SCIM)is proposed.The influence of geometric parameters of the end-ring on the performance characteristics,including starting(locked rotor)torque,pull-up and break down torque,starting current,rotor electric parameters,current density,power losses,and efficiency have been comprehensively investigated.It has been revealed that among the other end-ring design parameters,the ring thickness has a significant effect on the performance characteristics.An optimal end-ring thickness is determined,and its performance characteristics have been compared to those of its initial counterpart.Numeric and parametric analyses have been conducted using a 2D time-stepping finite element method(FEM).The FEM results were validated using experimental measurements obtained from an 11 kW SCIM prototype.
基金supported by the National Natural Science Foundation of China“Research on Cross-sector Competition Effect and Regulatory Policy of Digital Platforms Based on Inter-platform Network Externalities”(Grant No.72103085).
文摘Data is a key asset for digital platforms,and mergers and acquisitions(M&As)are an important way for platform enterprises to acquire it.The types of data obtained from intra-industry and cross-sector M&As differ,as does the extent to which they interact within or between platforms.The impact of such data on corporate market performance is an important question to consider when selecting strategies for digital platform M&As.Based on our research on advertising-driven platforms,we developed a two-stage Hotelling game model for comparing the market performance effects of intra-industry M&As and cross-sector M&As for digital platforms.We carried out an empirical test using relevant data from advertising-driven digital platforms between 2009 and 2021,as well as a case study on Baidu’s M&A activities.Our research discovered that intra-industry M&As driven by“data economies of scale”and cross-sector M&As driven by“data economies of scope”are both beneficial to the market performance of platform enterprises.Intra-industry M&As have a more significant positive effect on the market performance of platform enterprises because the same types of data are easier to integrate and develop the“network effect of data scale”.From a data factor perspective,this paper reveals the inherent economic logic by which different types of M&As influence the market performance of digital platforms,as well as policymaking recommendations for all digital platforms to select M&A strategies based on data scale,data scope,and the network effect of data.
基金supported by the Beijing Social Science Fund, China (17LJB007)the MOE (Ministry of Education, China) Project of Key Research Institute of Humanities and Social Sciences at Universities (17JJD910002)the 111 Project (B17050)
文摘Crop insurance in China is currently adopting the premium pricing strategy of "One Province One Rate", which appears to be in line with the systematic risk characteristics within crop insurance. This research aims to investigate the theoretical rationalization of this pricing strategy and its implications using the spatial lag model and the county-level data from the 45 corn plant counties of Jilin Province, China. Results corroborate that:(1) the spatial spillover effect of the corn yield risk is significant in Jilin but decreases rapidly when the risk unit includes more than eight counties; and(2) separating Jilin Province into eight risk zones for corn insurance will significantly reduce the high cross-subsidy phenomenon arising from the "One Province One Rate" strategy and shall benefit poor peasants in the region as well. This paper not only proves the existence of a systematic risk of crop insurance but also reveals that the spatial correlation and systemic features of the crop yield risk do not create a solid foundation for the current pricing strategy of "One Province One Rate". These conclusions will undoubtedly provide important references and empirical evidence for the role of China’s crop insurance in poverty alleviation.
文摘We consider a risk model with a premium rate which varies with the level of free reserves. In this model, the occurrence of claims is described by a Cox process with Markov intensity process, and the influence of stochastic factors is considered by adding a diffusion process. The integro-differential equation for the ruin probability is derived by a infinitesimal method. Key words ruin probability - variable premium rate - diffusion process - Markov intensity CLC number O 211.9 Foundation item: Supported by the National Natural Science Foundation of China (10071058, 70273029)
文摘By analyzing the cause of too high premium rate of pension insurance at present and discussing the current practice of Chinese Pension Insurance System, three models to determine the reasonable paying level of premium, returning level of retirement pay and premium rate are established. Comparatively speaking, these models solve the problem of the determination of the premium rate more scientifically and offer an effective analyzing means to the improvement of the Chinese Pension Insurance System.
基金supported by National Natural Science Foundation of China(11471218)Hebei Higher School Science and Technology Research Projects(ZD20131017)Joint Doctoral Training Foundation of HEBUT(2018GN0001)。
文摘This paper concerns an optimal dividend-penalty problem for the risk models with surplus-dependent premiums.The objective is to maximize the difference of the expected cumulative discounted dividend payments received until the moment of ruin and a discounted penalty payment taken at the moment of ruin.Since the value function may be not smooth enough to be the classical solution of the HJB equation,the viscosity solution is involved.The optimal value function can be characterized as the smallest viscosity supersolution of the HJB equation and the optimal dividend-penalty strategy has a band structure.Finally,some numerical examples with gamma distribution for the claims are analyzed.
文摘In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain.
文摘A differential fatherhood premium exists among selected groups of fathers of various socio-economic backgrounds. Besides marital status, residential arrangement, biological paternity, and other demographic dimensions, the mechanisms associated with fathers' structural characteristics of work that produce divergent labor market outcomes are less well understood. The authors leveraged the cases of productivity and specialization, family and responsibility, and compensating differentials and examined the impacts of work context and occupational characteristics on the pay gap between fathers and non-fathers Based on joint data from the 1997-2015 National Longitudinal Survey of Youth (NLSY97) and Occupational Information Network (O'NET) (n -- 37,138), the authors used fixed-effects models to estimate the associations between job features and the fatherhood premium. The regression results showed that occupations entailing competition and requiring on-the-job training are associated with more wage bonus; occupations offering inflexible schedule are associated with less wage gain These work-related characteristics further emphasize fathers' work structure and context, human capital accumulation, and work-family conflict. Overall, these findings are consistent with the theoretical perspectives of productivity and specialization and compensating differentials, adding new evidences to the structural explanations of the fatherhood premium.
基金Supported by National Excellent Doctoral Dissertation Cultivation Fund Project,Hunan Agricultural University (GYB201003)
文摘First,using the law of large numbers,I analyze the setting principle of agricultural insurance premium rate,and take the case of setting of adult sow premium rate for study,to draw the conclusion that with the continuous promotion of agricultural insurance,increase in the types of agricultural insurance and increase in the number of the insured,the premium rate should also be adjusted opportunely.Then,on the basis of Bayes' theorem,I adjust and calibrate the claim frequency and the average claim,in order to correctly adjust agricultural insurance premium rate;take the case of forest insurance for premium rate adjustment analysis.In setting and adjustment of agricultural insurance premium rate,in order to make the expected results well close to the real results,it is necessary to apply the probability estimates in a large number of risk units;focus on the establishment of agricultural risk database,to timely adjust agricultural insurance premium rate.
基金Supported by the National Natural Science Foundation of China (70273029)
文摘Let u ∈ R ,for any ω 〉 0, the processes X^ε = {X^ε(t); 0 ≤ t≤ 1} are governed by the following random evolution equations dX^ε(t)= b(X^ε(t),v(t))dt-εdSt/ε, where S={St; 0≤t≤1} is a compound Poisson process, the process v={v(t); 0≤t≤1} is independent of S and takes values in R^m. We derive the large deviation principle for{(X^ε,v(.)); ε〉0} when ε↓0 by approximation method and contraction principle, which will be meaningful for us to find out the path property for the risk process of this type.
基金Supported by International Cooperation Project of China's Agricultural Insurance (DelPHE ACIC)
文摘Based on theoretical analysis of crop risk and premium rate setting,we take the case of premium rate setting of insurance on cotton yield in Shache County,Shaya County and Aksu City of Xinjiang.Using parametric methods and insurance actuarial technique,we select the optimal model for risk fitting of cotton yield in three areas;compare the premium rate calculated accurately under four risk distribution assumptions of cotton yield,and the rational premium rate,to analyze the impact of risk distribution of crop yield on premium rate setting.The empirical results show that the Logistic distribution is the optimal distribution for risk fitting of cotton yield in three areas;the rational net premium rate of cotton insurance in three areas is 7.62%,6.32% and 4.96%,respectively;there are errors in premium rate setting under assumptions of normal distribution,normalized skew distribution and Weibull distribution,ranging from 0.2 percentage points to 8 percentage points.Thus,it indicates that the selection of risk distribution model of yield directly affects the accuracy of premium rate setting of crops,and the key to accurate premium rate setting of crops lies in correct selection of risk distribution model of yield.
文摘Premium thread connection tubing and casing products are non-API products that are used in severe oil field conditions, such as deep wells ,ultra deep wells, high pressure gas wells, horizontal wells and steam injection wells, etc. In order to meet the requirements of oilfields for premium thread connection oil country tubular goods ( OCTG), Baosteel developed its own series of premium thread connection tubing and casing products that are protected by intellectual property rights. This study introduces the process of developing the premium thread connection tubing and casing products, their characteristics, and their actual application in oil fields. It hopes to give customers a better understanding of Premium thread connection tubing and casing products from Baosteel.
基金The NSF(10971081,11001105,11071126,10926156,11071269,J0730101)of ChinaSpecialized Research Fund(20070183023)for the Doctoral Program of Higher Education+2 种基金Program(NCET-08-237)for New Century Excellent Talents in UniversityScientific Research Fund(200810024,200903278)of Jilin University985 project of Jilin University
文摘In this paper, we propose a new risk measure which is based on the Or- licz premium principle to characterize catastrophe risk premium. The intention is to develop a formulation strategy for Catastrophe Fund. The logarithm equivalent form of reinsurance premium is regarded as the retention of reinsurer, and the differential earnings between the reinsurance premium and the reinsurer's retention is accumu- lated as a part of Catastrophe Fund. We demonstrate that the aforementioned risk measure has some good properties, which are further confirmed by numerical simu- lations in R environment.
文摘Volatility is an important variable in the financial market. We propose a model-free implied volatility method to measure the volatility and test the volatility risk premium. The model-free implied volatility does not depend on the option pricing model, and extracts information from all the option contracts. We provide empirical evidence from the S & P 500 index option that model-free implied volatility is more accurate to forecast the future volatility and the volatility risk premium does not exist.
文摘We study the sample of 311 non-outstanding shares transfers from 2003 to 2004. The object of this study is to determine the extent to which premium can be explained by financial factors of firms. The intrinsic value of transferred shares with control right is different from the others. We find that the larger percent of share transferred, the higher premium will be paid. Current liability ratio interpreting the premium of non-outstanding shares transfers is negative related to short term debt. Price ratio can determine the premium level when the ratio of transfer share under 30 percent
文摘To participate in social insurance is a major social responsibility of enterprises, even it is a mandatory social policy, companies still escaped pay society insurance. The serious consequences of this phenomenon become increasingly prominent.it not only damaged the justice of labor market, but also violated the staffs interest. Various factors influence enterprise to participate in social insurance behavior .Human capital is the impact of insurance companies. This paper is mainly focusing on the theory analysis of different human capital participating behavior of enterprises. From the perspective of human capital, using the cost-benefit theory and rational choice theory in economics to explore participating behavior, enterprise employees of different human capital differences in attitude to attend social insurance. No matter enterprises with higher or lower human capital, enterprises and employees choose to participate in social insurance act consistently. But, it can improve participate of low human capital enterprise behavior when payment rate reduced. So, it is suggested that establishing a lower level of social insurance system is helpful to expand coverage, it can through e^tahllgh the sunnlementarv insurance system meet the needs of more people.
文摘Matrox3月27日宣布Matrox Rt.X2系列编辑平台30版驱动程序将支持最新推出的Adobe Creative Suite 3 Production Premiumg 和Adobe Premiere ProCS3软件。除此以外.MatroxRT×230版驱动程序还将提供对WindowsVqsta的支持、支持更多高清和标清摄像机及编辑分辨率.再加上新的实时特技。