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ON MULTIPLE WIENER INTEGRAL EXPANSIONS FOR D'-VALUED NONLINEAR RANDOM FUNCTIONALS
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作者 Wu Jianglun 《Acta Mathematica Scientia》 SCIE CSCD 1993年第2期220-228,共9页
In this paper,the multiple stochastic integral with respect to a Wiener D'-process is defined.And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integral ... In this paper,the multiple stochastic integral with respect to a Wiener D'-process is defined.And also it is shown that for a D'-valued nonlinear random functional there exists a sequence of multiple integral kernels such that the nonlinear functional can be expanded by series of multiple Wiener integrals of the integral kernels with respect to the Wiener D'-process. 展开更多
关键词 valueD NONLINEAR RANDOM functionalS ON MULTIPLE WIENER INTEGRAL EXPANSIONS FOR D ONB
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Dynamical distribution of continuous service time model involving non-Maxwellian collision kernel and value functions
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作者 Minfang Zhao Lingting Kong +1 位作者 Miao Liu Shaoyong Lai 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期340-348,共9页
The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of conti... The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of continuous service time,respectively.Using the statistical mechanical and asymptotic limit methods,Fokker–Planck equations are derived from the corresponding Boltzmann-type equations with non-Maxwellian collision kernels.The steady-state solutions of the Fokker–Planck equation are obtained in exact form.Numerical experiments are provided to support our results under different parameters. 展开更多
关键词 kinetic theory service time Fokker-Planck equation value function
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Classification of plant functional types based on the nutrition traits: a case study on alpine meadow community in the Zoigê Plateau 被引量:6
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作者 SHEN Song-tao ZHANG Shu-jie +1 位作者 FAN Min WANG Qing 《Journal of Mountain Science》 SCIE CSCD 2017年第10期2003-2012,共10页
The ecological concept of Plant Functional Types(PFTs), which refers to the assemblage of plants with certain functional traits, has been introduced for the study of plant responses to the environment change and hum... The ecological concept of Plant Functional Types(PFTs), which refers to the assemblage of plants with certain functional traits, has been introduced for the study of plant responses to the environment change and human disturbance. Taking the alpine meadow community in the Zoigê Plateau as a study case, this paper classified PFTs in terms of plant nutrition traits. The sequential results are as follows.(1) The main herbages in the Zoigê Plateau included 16 species in 5 families. Among the five families, Cyperaceae vegetation accounted for 81.37%of herbage area in total, while the remaining 4families occupied less than 20%. As for the species,Kobresia setchwanensis Hand.-Maizz. was dominant,accounting for 48.74% of the total area; while the remaining 51.26% was comprised of Polygonum viviparum L., Anaphalis fiavescens Hand.-Mazz.,Stipa aliena Keng and other species.(2) By using the Principal Component Analysis(PCA), the assessment of herbages nutrition was carried out based on the comprehensive multi-index evaluation model.Polygonum viviparum L. had the highest nutritional value score(1.43), and Stipa aliena Keng had the lowest(-1.40). Nutritional value of herbage species had a significantly positive correlation with altitude(P&lt;0.01) in the Zoigê Plateau.(3) Based on the nutritional values, herbages in the Zoigê Plateau could be grouped into 3 nutrition PFTs(high, medium and low) by using the Natural Breaks(Jenks) method. 展开更多
关键词 Plant functional types Nutritional value Forage resource management the Zoigê Plateau
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AN INEQUALITY ON THE ZEROS AND POLES OF VECTOR VALUED MEROMORPHIC FUNCTIONS 被引量:1
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作者 吴昭君 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期380-386,共7页
The author proves that if f : C → C^n is a transcendental vector valued mero-morphic function of finite order and assume, This result extends the related results for meromorphic function by Singh and Kulkarni.
关键词 Characteristic function vector valued meromorphic function ZERO POLE
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Resolution of Grandi’s Paradox as Extended to Complex Valued Functions 被引量:2
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作者 Serdar Beji 《Advances in Pure Mathematics》 2020年第8期447-463,共17页
Grandi’s paradox, which was posed for a real function of the form <span style="white-space:nowrap;">1/(1+ x), has been resolved and extended to complex valued functions. Resolution of this approximate... Grandi’s paradox, which was posed for a real function of the form <span style="white-space:nowrap;">1/(1+ x), has been resolved and extended to complex valued functions. Resolution of this approximately three-hundred-year-old paradox is accomplished by the use of a consistent truncation approach that can be applied to all the series expansions of Grandi-type functions. Furthermore, a new technique for improving the convergence characteristics of power series with alternating signs is introduced. The technique works by successively averaging a series at different orders of truncation. A sound theoretical justification of the successive averaging method is demonstrated by two different series expansions of the function <span style="white-space:nowrap;">1/(1+ e<sup>x </sup>) . Grandi-type complex valued functions such as <span style="white-space:nowrap;">1/(i + x) are expressed as consistently-truncated and convergence-improved forms and Fagnano’s formula is established from the series expansions of these functions. A Grandi-type general complex valued function <img src="Edit_f4efd7cd-6853-4ca4-b4dc-00f0b798c277.png" width="80" height="24" alt="" /> is introduced and expanded to a consistently truncated and successively averaged series. Finally, an unorthodox application of the successive averaging method to polynomials is presented. 展开更多
关键词 Grandi’s Paradox Real and Complex valued Functions Series Expansions
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Estimation of maximum inclusion by statistics of extreme values method in bearing steel 被引量:3
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作者 Chao Tian Jian-hui Liu +1 位作者 Heng-chang Lu Han Dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第11期1131-1136,共6页
A statistic method, statistics of extreme values (SEV), was described in detail, which can esti mate the size of maximum inclusion in steel. The characteristic size of the maximum inclusion in a high clean bearing s... A statistic method, statistics of extreme values (SEV), was described in detail, which can esti mate the size of maximum inclusion in steel. The characteristic size of the maximum inclusion in a high clean bearing steel (GCrl5) was evaluated by this method, and the morphology and corn position of large inclusions found were analyzed by scanning electron microscopy (SEM). When standard inspection area (S0) is 280 mm2, the characteristic size of the biggest inclusion found in 30 standard inspection area is 23.93 μm, and it has a 99.9% probability of the characteristic size of maximum inclusion predicted being no larger than 36.85μm in the experimental steel. SEM result shows that large inclusions found are mainly composed of CaS, calcium-aluminate and MgO. Compositing widely exists in large inclusions in high clean bearing steel. Compared with traditional evaluation method, SEV method mainly focuses on inclusion size, and the esti- mation result is not affected by inclusion types. SEV method is suitable for the inclusion eval uation of high clean bearing steel. 展开更多
关键词 Nonmetallic inclusion Statistics of extreme values Gumbel distribution function Likelihood function estimation
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Value Evaluation of Water Ecosystem Services——A Case Study of Changshu City 被引量:1
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作者 GAN Yue-yun JIN Hui +1 位作者 CHEN Xing ZHANG Qi-cheng 《Meteorological and Environmental Research》 2012年第10期40-42,共3页
[ Objective] The study aimed to quantitatively assess the values of water ecosystem services. [ Method] Combining the market value, travel cost and restoration cost method, the ecological services and their economic v... [ Objective] The study aimed to quantitatively assess the values of water ecosystem services. [ Method] Combining the market value, travel cost and restoration cost method, the ecological services and their economic values of the lake Taodangmian were assessed from aspects of water supply, recreation and tourism, water purification and biodiversity maintenance. [ Resultl For the lake Taodangmian, its freshwater supply and tourism played more positive roles in the society than the others, while the functions of water purification and biodiversity maintenance brought negative effects, which shows that the ecological environment of Taodangmian has become increasingly worse and needs to be controlled and and protected further. [ Conclusion] The research could provide scientific references for the reasonable exploitation and utilization of water resources. 展开更多
关键词 Water ecosystem Service function values Assessment methods Taodangmian China
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Lipschitz continuity of the optimal value function and KKT solution set in indefinite quadratic programs
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作者 HAN You-pan CHEN Zhi-ping ZHANG Feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第1期102-110,共9页
When all the involved data in indefinite quadratic programs change simultaneously, we show the locally Lipschtiz continuity of the KKT set of the quadratic programming problem firstly, then we establish the locally Li... When all the involved data in indefinite quadratic programs change simultaneously, we show the locally Lipschtiz continuity of the KKT set of the quadratic programming problem firstly, then we establish the locally Lipschtiz continuity of the KKT solution set. Finally, the similar conclusion for the corresponding optimal value function is obtained. 展开更多
关键词 quadratic program Lipschitz continuity value function feasible solution KKT solution set.
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Continuity of the optimal value function and optimal solutions of parametric mixed-integer quadratic programs
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作者 CHEN Zhi-ping HAN You-pan Department of Scientific Computing and Applied Software, Faculty of Science, Xi’an Jiaotong University, Xi’an 710049, China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第4期391-399,共9页
To properly describe and solve complex decision problems, research on theoretical properties and solution of mixed-integer quadratic programs is becoming very important. We establish in this paper different Lipschitz-... To properly describe and solve complex decision problems, research on theoretical properties and solution of mixed-integer quadratic programs is becoming very important. We establish in this paper different Lipschitz-type continuity results about the optimal value function and optimal solutions of mixed-integer parametric quadratic programs with parameters in the linear part of the objective function and in the right-hand sides of the linear constraints. The obtained results extend some existing results for continuous quadratic programs, and, more importantly, lay the foundation for further theoretical study and corresponding algorithm analysis on mixed-integer quadratic programs. 展开更多
关键词 MIXED-INTEGER quadratic program optimal value function optimal solution.
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Multiagent reinforcement learning through merging individually learned value functions
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作者 张化祥 黄上腾 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第3期346-350,共5页
In cooperative multiagent systems, to learn the optimal policies of multiagents is very difficult. As the numbers of states and actions increase exponentially with the number of agents, their action policies become mo... In cooperative multiagent systems, to learn the optimal policies of multiagents is very difficult. As the numbers of states and actions increase exponentially with the number of agents, their action policies become more intractable. By learning these value functions, an agent can learn its optimal action policies for a task. If a task can be decomposed into several subtasks and the agents have learned the optimal value functions for each subtask, this knowledge can be helpful for the agents in learning the optimal action policies for the whole task when they are acting simultaneously. When merging the agents’ independently learned optimal value functions, a novel multiagent online reinforcement learning algorithm LU-Q is proposed. By applying a transformation to the individually learned value functions, the constraints on the optimal value functions of each subtask are loosened. In each learning iteration process in algorithm LU-Q, the agents’ joint action set in a state is processed. Some actions of that state are pruned from the available action set according to the defined multiagent value function in LU-Q. As the items of the available action set of each state are reduced gradually in the iteration process of LU-Q, the convergence of the value functions is accelerated. LU-Q’s effectiveness, soundness and convergence are analyzed, and the experimental results show that the learning performance of LU-Q is better than the performance of standard Q learning. 展开更多
关键词 reinforcement learning MULTIAGENT value function
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BSDES IN GAMES,COUPLED WITH THE VALUE FUNCTIONS.ASSOCIATED NONLOCAL BELLMAN-ISAACS EQUATIONS
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作者 郝涛 李娟 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1497-1518,共22页
We establish a new type of backward stochastic differential equations(BSDEs)connected with stochastic differential games(SDGs), namely, BSDEs strongly coupled with the lower and the upper value functions of SDGs, wher... We establish a new type of backward stochastic differential equations(BSDEs)connected with stochastic differential games(SDGs), namely, BSDEs strongly coupled with the lower and the upper value functions of SDGs, where the lower and the upper value functions are defined through this BSDE. The existence and the uniqueness theorem and comparison theorem are proved for such equations with the help of an iteration method. We also show that the lower and the upper value functions satisfy the dynamic programming principle. Moreover, we study the associated Hamilton-Jacobi-Bellman-Isaacs(HJB-Isaacs)equations, which are nonlocal, and strongly coupled with the lower and the upper value functions. Using a new method, we characterize the pair(W, U) consisting of the lower and the upper value functions as the unique viscosity solution of our nonlocal HJB-Isaacs equation. Furthermore, the game has a value under the Isaacs’ condition. 展开更多
关键词 Mc Kean-Vlasov SDE BSDE coupled with the lower and the upper value functions dynamic programming principle mean-field BSDE viscosity solution coupled nonlocal HJB-Isaacs equation Isaacs' condition
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Saddle Point Optimality Criteria of Interval Valued Non-Linear Programming Problem
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作者 Md Sadikur Rahman Emad E.Mahmoud +2 位作者 Ali Akbar Shaikh Abdel-Haleem Abdel-Aty Asoke Kumar Bhunia 《Computer Systems Science & Engineering》 SCIE EI 2021年第9期351-364,共14页
The present paper aims to develop the Kuhn-Tucker and Fritz John criteria for saddle point optimality of interval-valued nonlinear programming problem.To achieve the study objective,we have proposed the definition of ... The present paper aims to develop the Kuhn-Tucker and Fritz John criteria for saddle point optimality of interval-valued nonlinear programming problem.To achieve the study objective,we have proposed the definition of minimizer and maximizer of an interval-valued non-linear programming problem.Also,we have introduced the interval-valued Fritz-John and Kuhn Tucker saddle point problems.After that,we have established both the necessary and sufficient optimality conditions of an interval-valued non-linear minimization problem.Next,we have shown that both the saddle point conditions(Fritz-John and Kuhn-Tucker)are sufficient without any convexity requirements.Then with the convexity requirements,we have established that these saddle point optimality criteria are the necessary conditions for optimality of an interval-valued non-linear programming with real-valued constraints.Here,all the results are derived with the help of interval order relations.Finally,we illustrate all the results with the help of a numerical example. 展开更多
关键词 Convexity of interval valued function extended Fritz-John theorem Interval order relation Karlin’s constraint saddle point optimality
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ON VECTOR VALUED FUNCTION APPROXIMATION USING A PEAK NORM
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作者 G.A.Watson 《Analysis in Theory and Applications》 1996年第2期1-12,共12页
A peak norm is defined for Lp spaces of E-valued Bochner integrable functions, where E is a Banach space, and best approximations from a sun to elements of the space are characterized. Applications are given to some f... A peak norm is defined for Lp spaces of E-valued Bochner integrable functions, where E is a Banach space, and best approximations from a sun to elements of the space are characterized. Applications are given to some families of simultaneous best approximation problems. 展开更多
关键词 ON VECTOR valueD FUNCTION APPROXIMATION USING A PEAK NORM 任气
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DIFFERENTIAL POLYNOMIALS SHARING ONE VALUE
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作者 张继龙 杨连中 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1865-1874,共10页
In this paper, we investigate uniqueness problems of differential polynomials of meromorphic functions. Let a, b be non-zero constants and let n, k be positive integers satisfying n ≥ 3k + 12. If f^n+ af^(k)and ... In this paper, we investigate uniqueness problems of differential polynomials of meromorphic functions. Let a, b be non-zero constants and let n, k be positive integers satisfying n ≥ 3k + 12. If f^n+ af^(k)and g^n+ ag^(k)share b CM and the b-points of f^n+ af^(k)are not the zeros of f and g, then f and g are either equal or closely related. 展开更多
关键词 meromorphic function differential polynomial share value
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VALIDITY OF SPIROMETRIC REFERENCE VALUES FOR HEALTHY ADULTS IN SHANGHAI
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作者 范亮 万欢英 +2 位作者 程齐俭 倪瑾华 李庆云 《Medical Bulletin of Shanghai Jiaotong University》 CAS 2011年第1期12-17,共6页
Objective To evaluate the validity of current spirometric reference values for healthy adults in Shanghai.Methods Healthy non-smoking adults without respiratory diseases were randomly enrolled in the study.Gender,age,... Objective To evaluate the validity of current spirometric reference values for healthy adults in Shanghai.Methods Healthy non-smoking adults without respiratory diseases were randomly enrolled in the study.Gender,age,standing height,body weight and spirometric parameters were obtained.The parameters were compared with reference values from current prediction equations with or without conversion factors.Results A total of 127 healthy adults (60 males and 67 females) aged 18-57 years participated in the study.In the study,pulmonary function parameters of healthy adults,especially of female adults were higher than predicted values,according to prediction equations from Chinese subjects in Shanghai.There were discrepancies between measuring values and reference values from foreign prediction equations with or without conversion factors.Conclusion Spirometric parameters of healthy adults,especially female population in Shanghai might be underestimated by present reference values from Chinese subjects.Foreign reference values and their conversion factors are not able to match measuring values.Validity of spirometric reference values for adults in Shanghai should be reassessed. 展开更多
关键词 pulmonary function reference value Shanghai
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The Expanding Analysis of Enterprise's Human Capital Investment Value
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作者 Guang Xia 《Chinese Business Review》 2005年第9期68-72,共5页
Value is the scale that appraises whether the comparison between a certain thing and its realization which we need to consume is rational. The paper appraises the investment value and incomes of human capital by apply... Value is the scale that appraises whether the comparison between a certain thing and its realization which we need to consume is rational. The paper appraises the investment value and incomes of human capital by applying value engineering method. It elaborates the investment structure and contents of human capital first, and then analyzes and summarizes various functions of enterprise's human capital. It educes the production function and the optimum equilibrium solution of human capital on this basis. Finally, it appraises the investment value of human capital by applying VE method. Thus we will apply a new method in the human capital field. 展开更多
关键词 human capital human investment function value engineering
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Estimation of Relative Ecological Value of Returning Farmland to Forest & Mountain Enclosure for Grazing Prohibition——A case study in Yongxing Township of Jingyuan County,Gansu Province
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作者 CHANG Zhao-feng CHEN Bin-pu +2 位作者 QIAO Juan CHANG Fang FAN Bao-li 《Animal Husbandry and Feed Science》 CAS 2013年第4期162-168,171,共8页
[Objective]Returning farmland to forest and mountain enclosure for grazing prohibition ecological effect and economy rationality were explored.[Methods]A case study of returning farmland to forest and barren hills gra... [Objective]Returning farmland to forest and mountain enclosure for grazing prohibition ecological effect and economy rationality were explored.[Methods]A case study of returning farmland to forest and barren hills grazing prohibition in Yongxing Township of Jingyuan County was used to discuss and estimate the relative ecological function and relative ecological value.[Results]1)The ecological value of the forest of returning farmland was far more than the sum of the ecological value of farm crops and the agricultural output,and also more than the national subsidy standard.So the state policy of returning farmland to forests is not only favorable to local eco-environment restoration,but also reasonable in economic development.2)The ecological value of mountain enclosure for grazing prohibition was less than the opportunity cost of prohibiting grazing,also less than the national subsidy standard.The sum of the relative ecological value of prohibiting grazing and the state subsidies was more than the opportunity cost of prohibiting grazing.However,the ecological value of new vegetation through returning farmland to forest project was greater than the China's average ecological value of grassland.[Conclusion]The relative ecological value can be used to solve the problems in the equivalent conversion among various ecological indexes and between ecological indexes and economic indexes. 展开更多
关键词 Returning farmland to forest Mountain enclosure for grazing prohibition Relative ecological function Relative ecological value Jingyuan County
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Deep reinforcement learning using least-squares truncated temporal-difference
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作者 Junkai Ren Yixing Lan +3 位作者 Xin Xu Yichuan Zhang Qiang Fang Yujun Zeng 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第2期425-439,共15页
Policy evaluation(PE)is a critical sub-problem in reinforcement learning,which estimates the value function for a given policy and can be used for policy improvement.However,there still exist some limitations in curre... Policy evaluation(PE)is a critical sub-problem in reinforcement learning,which estimates the value function for a given policy and can be used for policy improvement.However,there still exist some limitations in current PE methods,such as low sample efficiency and local convergence,especially on complex tasks.In this study,a novel PE algorithm called Least-Squares Truncated Temporal-Difference learning(LST2D)is proposed.In LST2D,an adaptive truncation mechanism is designed,which effectively takes advantage of the fast convergence property of Least-Squares Temporal Difference learning and the asymptotic convergence property of Temporal Difference learning(TD).Then,two feature pre-training methods are utilised to improve the approximation ability of LST2D.Furthermore,an Actor-Critic algorithm based on LST2D and pre-trained feature representations(ACLPF)is proposed,where LST2D is integrated into the critic network to improve learning-prediction efficiency.Comprehensive simulation studies were conducted on four robotic tasks,and the corresponding results illustrate the effectiveness of LST2D.The proposed ACLPF algorithm outperformed DQN,ACER and PPO in terms of sample efficiency and stability,which demonstrated that LST2D can be applied to online learning control problems by incorporating it into the actor-critic architecture. 展开更多
关键词 Deep reinforcement learning policy evaluation temporal difference value function approximation
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Research on the Coupled and Coordinated Development of Tourism and Transport in Chongqing Municipality
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作者 Mengmeng Shu 《Proceedings of Business and Economic Studies》 2024年第3期92-101,共10页
By examining the current status of tourism and transport research both domestically and internationally,and analyzing the development trends of Chongqing’s tourism and transport industry,this study evaluates the weig... By examining the current status of tourism and transport research both domestically and internationally,and analyzing the development trends of Chongqing’s tourism and transport industry,this study evaluates the weight indices and performs a coupling and coordination analysis of various indicators of Chongqing’s tourism and transport industry from 2011 to 2019.The following conclusions are drawn:(1)The value of the comprehensive evaluation function for tourism is higher than that of the transport industry,indicating that Chongqing’s tourism industry is in a period of vigorous development;(2)The degree of coupling coordination development between Chongqing’s tourism and transportation industries from 2011 to 2019 is rising.As the coupling coordination stage continues to improve,the level of coupling coordination also improves,with the overall trend showing a progression from mild dysfunction to primary coordination.Based on these conclusions,corresponding countermeasures are proposed to promote the coupling coordination between tourism and transport in Chongqing,and suggestions are made for the overall improvement of the transport industry and the sustainable development of the tourism industry. 展开更多
关键词 Chongqing Municipality TOURISM Transport industry Comprehensive evaluation function value Coupling coordination
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Concepts of keystone species and species importance in ecology
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作者 陆兆华 马玲 国庆喜 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期250-252,277,共4页
This paper discussed the keystone species concept and introduced the typical characteristics of keystone species and their identification in communities or ecosystems. Based on the research of the keystone species, th... This paper discussed the keystone species concept and introduced the typical characteristics of keystone species and their identification in communities or ecosystems. Based on the research of the keystone species, the concept of species importance (SI) was first advanced in this paper. The species importance can be simply understood as the important value of species in the ecosystem, which consists of three indexes: species structural important value (SIV), functional important value (FIV) and dynamical important value (DIV). With the indexes, the evaluation was also made on species importance of arbor trees in the Three-Hardwood forests (Fraxinus mandshurica, Juglans mandshurica, and Phellodendron amurense) ecosystem. 展开更多
关键词 Species importance Keystone species Structural important value functional important value Dynamical important value
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