Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rate...Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper.展开更多
In mixed fisheries where there is an increased ecological interdependence between two or more target species, the possibilities of fishing these species must be determined jointly, since catches of one species will im...In mixed fisheries where there is an increased ecological interdependence between two or more target species, the possibilities of fishing these species must be determined jointly, since catches of one species will impact the natural growth not only of that species but of the others, as well. The objective of this paper is to develop a predator-prey model for two major species caught by the EU fishing fleet on European Union fishing grounds. The predator and prey’s population dynamics follow the Lotka-Volterra equation and are assumed to be logic-based, and a lineal interaction between the predator and prey populations is assumed. Optimal single owner multispecies fishery management is analysed, and the applied model is solved, obtaining the equilibrium value of biomasses, catches, and net benefits of the mixed fishery. The results show that the MSY of the predator is higher than that estimated by ICES, while MSY for prey is lower. The sensitivity analysis of the results reveals that the biomass levels of both species decrease as the discount rate increases, while catches increase.展开更多
The controllability problem of heterogeneous interdependent group systems with undirected and directed topology is investigated in this paper. First, the interdependent model of the heterogeneous system is set up acco...The controllability problem of heterogeneous interdependent group systems with undirected and directed topology is investigated in this paper. First, the interdependent model of the heterogeneous system is set up according to the difference of individual characteristics. An extended distributed protocol with the external sliding-mode control is designed, under which it is shown that a heterogeneous interdependent group system is controllable when the corresponding communication topology is controllable. Then, using the network eigenvalue method, the driving individuals are determined for a heterogeneous system with undirected topology. Under directed topology, the maximum match method is utilized to confirm the driving individuals. Some sufficient and necessary conditions are presented to assure that the heterogeneous interdependent group system is structurally controllable. Via theoretical analysis, the controllability of heterogeneous interdependent systems is related to the interdependent manner and the structure of the heterogeneous system. Numerical simulations are provided to demonstrate the effectiveness of the theoretical results.展开更多
目的:调查不孕症初诊夫妻的生育压力、二元应对和生育生活质量现状,探讨二元应对在生育压力与生育生活质量间的主客体互倚中介效应。方法:本研究为横断面研究设计,采取便利抽样法选取2023年9—11月本中心初诊不孕症、拟进行辅助生殖治疗...目的:调查不孕症初诊夫妻的生育压力、二元应对和生育生活质量现状,探讨二元应对在生育压力与生育生活质量间的主客体互倚中介效应。方法:本研究为横断面研究设计,采取便利抽样法选取2023年9—11月本中心初诊不孕症、拟进行辅助生殖治疗的267对夫妻为研究对象。采用一般资料调查表、生育压力量表(fertility problem inventory,FPI)、二元应对量表(dyadic coping inventory,DCI)和生育生活质量量表(fertility quality of life,FertiQoL)对不孕症夫妻的生育压力、二元应对和生育生活质量进行调查。采用SPSS 26.0软件对数据进行统计分析,运用R4.3.2软件进行主客体互倚中介效应分析。结果:共发放问卷不孕症夫妻267对,回收有效问卷257对,有效回收率为96.25%。Pearson相关分析显示,不孕症夫妻生育压力与二元应对、生育生活质量呈显著相关性(均P<0.001)。主体-主体效应中,二元应对在女方及男方的生育压力和生育生活质量间的主体中介效应均成立(β=-0.35,P<0.05和β=-0.09,P<0.05);伴侣-主体效应中,女方的生育压力能够通过影响男方的二元应对影响男方的生育生活质量(β=-0.04,P<0.05);男方的二元应对能够通过影响女方的二元应对影响女方的生育生活质量(β=0.06,P<0.05)。结论:不孕症夫妻在应对疾病过程中的行为反应是相互关联、相互影响的,临床诊治不孕症时在考虑一方生育压力的同时,还要考虑其自身及其与配偶之间的生育压力的相互影响,给予相应的干预措施提高双方的生育生活质量。展开更多
文摘Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper.
文摘In mixed fisheries where there is an increased ecological interdependence between two or more target species, the possibilities of fishing these species must be determined jointly, since catches of one species will impact the natural growth not only of that species but of the others, as well. The objective of this paper is to develop a predator-prey model for two major species caught by the EU fishing fleet on European Union fishing grounds. The predator and prey’s population dynamics follow the Lotka-Volterra equation and are assumed to be logic-based, and a lineal interaction between the predator and prey populations is assumed. Optimal single owner multispecies fishery management is analysed, and the applied model is solved, obtaining the equilibrium value of biomasses, catches, and net benefits of the mixed fishery. The results show that the MSY of the predator is higher than that estimated by ICES, while MSY for prey is lower. The sensitivity analysis of the results reveals that the biomass levels of both species decrease as the discount rate increases, while catches increase.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61603137 and 11662002)the Innovation Team Project of Jiangxi Provincial Innovation Drive "5511" Advantaged Science and Technology(Grant No.20165BCB19011)+2 种基金the Natural Science Foundation of Jiangxi Province,China(Grant Nos.20171BAB212016 and 20171BAB202029)the Key Research and Development Project of the Technology Department of Jiangxi Province,China(Grant No.20161BBE53008)the Doctoral Scientific Research Foundation of East China Jiaotong University(Grant No.2003418002)
文摘The controllability problem of heterogeneous interdependent group systems with undirected and directed topology is investigated in this paper. First, the interdependent model of the heterogeneous system is set up according to the difference of individual characteristics. An extended distributed protocol with the external sliding-mode control is designed, under which it is shown that a heterogeneous interdependent group system is controllable when the corresponding communication topology is controllable. Then, using the network eigenvalue method, the driving individuals are determined for a heterogeneous system with undirected topology. Under directed topology, the maximum match method is utilized to confirm the driving individuals. Some sufficient and necessary conditions are presented to assure that the heterogeneous interdependent group system is structurally controllable. Via theoretical analysis, the controllability of heterogeneous interdependent systems is related to the interdependent manner and the structure of the heterogeneous system. Numerical simulations are provided to demonstrate the effectiveness of the theoretical results.
文摘目的:调查不孕症初诊夫妻的生育压力、二元应对和生育生活质量现状,探讨二元应对在生育压力与生育生活质量间的主客体互倚中介效应。方法:本研究为横断面研究设计,采取便利抽样法选取2023年9—11月本中心初诊不孕症、拟进行辅助生殖治疗的267对夫妻为研究对象。采用一般资料调查表、生育压力量表(fertility problem inventory,FPI)、二元应对量表(dyadic coping inventory,DCI)和生育生活质量量表(fertility quality of life,FertiQoL)对不孕症夫妻的生育压力、二元应对和生育生活质量进行调查。采用SPSS 26.0软件对数据进行统计分析,运用R4.3.2软件进行主客体互倚中介效应分析。结果:共发放问卷不孕症夫妻267对,回收有效问卷257对,有效回收率为96.25%。Pearson相关分析显示,不孕症夫妻生育压力与二元应对、生育生活质量呈显著相关性(均P<0.001)。主体-主体效应中,二元应对在女方及男方的生育压力和生育生活质量间的主体中介效应均成立(β=-0.35,P<0.05和β=-0.09,P<0.05);伴侣-主体效应中,女方的生育压力能够通过影响男方的二元应对影响男方的生育生活质量(β=-0.04,P<0.05);男方的二元应对能够通过影响女方的二元应对影响女方的生育生活质量(β=0.06,P<0.05)。结论:不孕症夫妻在应对疾病过程中的行为反应是相互关联、相互影响的,临床诊治不孕症时在考虑一方生育压力的同时,还要考虑其自身及其与配偶之间的生育压力的相互影响,给予相应的干预措施提高双方的生育生活质量。
