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FUNCTIONAL ANALYSIS METHOD FOR THE M/G/1 QUEUEING MODEL WITH OPTIONAL SECOND SERVICE 被引量:3
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作者 艾尼.吾甫尔 艾合买提.卡斯木 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1301-1330,共30页
By studying the spectral properties of the underlying operator corresponding to the M/G/1 queueing model with optional second service we obtain that the time-dependent solution of the model strongly converges to its s... By studying the spectral properties of the underlying operator corresponding to the M/G/1 queueing model with optional second service we obtain that the time-dependent solution of the model strongly converges to its steady-state solution. We also show that the time-dependent queueing size at the departure point converges to the corresponding steady-state queueing size at the departure point. 展开更多
关键词 M/G/1 queueing model with optional second service EIGENVALUE resolvent set
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Optimization on bicriterion policies for M/G/1 system with second optional service 被引量:1
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作者 Jau-chuan KE Yunn-kuang CHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1437-1445,共9页
We compare the optimal operating cost of the two bicriterion policies, <p,T> and <p,N>, for an M/G/1 queueing system with second optional service, in which the length of the vacation period is randomly con... We compare the optimal operating cost of the two bicriterion policies, <p,T> and <p,N>, for an M/G/1 queueing system with second optional service, in which the length of the vacation period is randomly controlled either by the number of arrivals during the idle period or by a timer. After all the customers are served in the queue exhaustively, the server immediately takes a vacation and may operate <p,T> policy or <p,N> policy. For the two bicriterion policies, the total average cost function per unit time is developed to search the optimal stationary operating policies at a minimum cost. Based upon the optimal cost the explicit forms for joint optimum threshold values of (p,T) and (p,N) are obtained. 展开更多
关键词 Average operating cost Bicriterion policy Optimization comparisons optional service Optimal threshold values
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OPTIONAL AND PREDICTABLE PROJECTIONS OF SET-VALUED MEASURABLE PROCESSES
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作者 Wang Rongmingof Statistcs,East China Normal Univ.,Shanghai 200062. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第3期323-329,共7页
In this paper,the optional and predictable projections of set-valued measurable processes are studied.The existence and uniqueness of optional and predictable projections of set-valued measurable processes are proved ... In this paper,the optional and predictable projections of set-valued measurable processes are studied.The existence and uniqueness of optional and predictable projections of set-valued measurable processes are proved under proper circumstances. 展开更多
关键词 Set-valued conditional expectation essential(convex)closure optional projection predictable projection measurable processes.
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Offering English and American Literature Optional Courses to Enhance Humanistic Qualities of Students in Universities of Science and Technology
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作者 WANG Huan 《Sino-US English Teaching》 2012年第9期1486-1492,共7页
Recently, the universities of science and technology pay more attention to their own specialized subjects and tak, little notice of humanities. This phenomenon results in the weakness of college students' humanistic ... Recently, the universities of science and technology pay more attention to their own specialized subjects and tak, little notice of humanities. This phenomenon results in the weakness of college students' humanistic qualities, Therefore, cultivating and enhancing students' humanistic qualities in universities of science and technolog become the main issues that are viewed intensively by the current educational circles. This paper analyzes th, current situation of English and American literature optional courses in universities of science and technolog3, gives the importance of offering the optional courses of English and American literature, and analyzes the activ roles and important significance of optional courses of English and American literature in the course of humanisti qualities of students in universities of science and technology. This paper also gives the necessities and ne~ methods of giving the optional courses of English and American literature under the circumstances of colleg, English teaching reform 展开更多
关键词 English and American literature optional courses students in universities of science and technology humanistic quality college English teaching
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China-EU Forum on Anti-Torture Convention and Optional Protocol
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作者 CHEN WEIDONG 《The Journal of Human Rights》 2006年第6期36-38,共3页
A China-Europe international forum on the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punish-ment and the optional protocol to the convention was held in Beijing from August 12-13, 2006,
关键词 Pro China-EU Forum on Anti-Torture Convention and optional Protocol EU
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Five Years after the Entry of Force of the Optional Protocol to the International Covenant on Economic,Social and Cultural Rights: Some Observations
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作者 孙世彦 《The Journal of Human Rights》 2018年第6期625-639,共15页
The optional Protocol to the international covenant on economic, Social and cultural Right was adopted in 2008 and entered into force in 2013? During the five years after its entry into force, 23 States have ratified ... The optional Protocol to the international covenant on economic, Social and cultural Right was adopted in 2008 and entered into force in 2013? During the five years after its entry into force, 23 States have ratified the optional Protocol, and 23 individual communications have been submitted to the committee on economic,Social and cultural Rights? comparing with the acceptance of individual communication procedures under other core international human rights treaties, the record of ratification of the optional Protocol is not satisfactory? in its examination of individual communications,the committee on economic, Social and cultural Rights has made detailed reasoning, extensively referred to its previous general comments, and in case of violations found, suggested both specific and general remedies? in its practice of examining individual communications, the committee on economic, Social and cultural Rights needs to clarify and define the rights under the covenant and their corresponding obligations, while maintaining its nature and role as a supervisory body, without expanding its competence to an unacceptable extent? 展开更多
关键词 International Covenant on Economic Social and Cultural Rights optional Protocol Committee on Economic Social and Cultural Rights individual communication
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弹性退休制度下谁更愿意延迟退休?——基于Option Value模型的微观模拟
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作者 郭秀云 李悦心 《人口与发展》 CSSCI 北大核心 2024年第4期132-144,共13页
人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、... 人口老龄化背景下延迟退休年龄、建立弹性退休制度是大势所趋。养老金激励是弹性退休制度的重要内容。建立期权价值模型和养老金给付及奖惩因子模型,基于中国家庭收入调查项目(CHIP2018)的数据,对不同特征人群的养老金峰值、期权价值、内部报酬率进行模拟。研究发现:养老金总财富随退休年龄“先增后减”,男性的峰值年龄早于女性;引入养老金“奖惩”机制有助于提高最优退休年龄,激励劳动者延迟退休;考虑闲暇偏好的异质性,男性参保者更倾向于早退休,而女性参保者特别是女性较高收入群体更愿意延迟退休;厌恶风险的参保者更有可能选择早退休。建议尽早建立弹性退休年龄政策体系,增加劳动者的选择权和制度灵活性;引入精算调节因子构建养老金奖惩机制,完善养老保险待遇计发办法。 展开更多
关键词 延迟退休 养老金财富 Option Value模型
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基于IUV_5G Option3X架构网络规划与部署设计
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作者 卢善勇 许景渊 《中国宽带》 2024年第1期1-3,共3页
本文基于IUV_5G Option3X架构,详细阐述了5G网络的规划与部署设计过程。首先介绍了5G NSA组网架构的背景和优势,然后深入探讨了IUV_5G全网部署与优化虚拟仿真平台的功能和应用。重点描述了核心网、无线网和承载网的部署过程,包括设备部... 本文基于IUV_5G Option3X架构,详细阐述了5G网络的规划与部署设计过程。首先介绍了5G NSA组网架构的背景和优势,然后深入探讨了IUV_5G全网部署与优化虚拟仿真平台的功能和应用。重点描述了核心网、无线网和承载网的部署过程,包括设备部署、数据配置和线路连接等具体步骤。通过业务验证确认了网络部署的成功,并对5G技术的未来发展进行了展望。 展开更多
关键词 5G网络 Option3X架构 NSA组网 虚拟仿真平台 核心网
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基于兴趣函数的多样化Option-Critic算法
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作者 栗军伟 刘全 +1 位作者 黄志刚 徐亚鹏 《计算机研究与发展》 EI CSCD 北大核心 2024年第12期3108-3120,共13页
Option框架作为分层强化学习的一种常用时序抽象方法,允许智能体在不同的时间尺度上学习策略,可以有效解决稀疏奖励问题.为了保证Option可以引导智能体访问更多的状态空间,一些方法通过引入基于互信息的内部奖励和终止函数来提升Option... Option框架作为分层强化学习的一种常用时序抽象方法,允许智能体在不同的时间尺度上学习策略,可以有效解决稀疏奖励问题.为了保证Option可以引导智能体访问更多的状态空间,一些方法通过引入基于互信息的内部奖励和终止函数来提升Option内部策略的多样性.但这会导致算法学习速度慢和内部策略的知识迁移能力低等问题,严重影响了算法性能.针对以上问题,提出基于兴趣函数优化的多样化Option-Critic算法(diversity-enriched Option-Critic algorithm with interest functions,DEOC-IF).该算法在多样化Option-Critic算法(diversity-enriched Option-Critic,DEOC)的基础上,通过引入兴趣函数约束上层策略对Option内部策略的选择,既保证了Option集合的多样性,又使得学习到的内部策略可以关注状态空间的不同区域,有利于提高算法的知识迁移能力,加快学习速度.此外,DEOC-IF算法引入一种新的兴趣函数更新梯度,有利于提高算法的探索能力.为了验证算法的有效性和知识迁移能力,分别在4房间导航任务、Mujoco和MiniWorld实验环境中,将DEOC-IF算法与其他最新算法进行对比实验.结果表明,DEOC-IF算法具有更好的性能优势和策略迁移能力. 展开更多
关键词 强化学习 时序抽象 Option框架 兴趣函数 Option-Critic算法
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基于互信息优化的Option-Critic算法
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作者 栗军伟 刘全 徐亚鹏 《计算机科学》 CSCD 北大核心 2024年第2期252-258,共7页
时序抽象作为分层强化学习的重要研究内容,允许分层强化学习智能体在不同的时间尺度上学习策略,可以有效解决深度强化学习难以处理的稀疏奖励问题。如何端到端地学习到优秀的时序抽象策略一直是分层强化学习研究面临的挑战。Option-Crit... 时序抽象作为分层强化学习的重要研究内容,允许分层强化学习智能体在不同的时间尺度上学习策略,可以有效解决深度强化学习难以处理的稀疏奖励问题。如何端到端地学习到优秀的时序抽象策略一直是分层强化学习研究面临的挑战。Option-Critic(OC)框架在Option框架的基础上,通过策略梯度理论,可以有效解决此问题。然而,在策略学习过程中,OC框架会出现Option内部策略动作分布变得十分相似的退化问题。该退化问题影响了OC框架的实验性能,导致Option的可解释性变差。为了解决上述问题,引入互信息知识作为内部奖励,并提出基于互信息优化的Option-Critic算法(Option-Critic Algorithm with Mutual Information Optimization,MIOOC)。MIOOC算法结合了近端策略Option-Critic(Proximal Policy Option-Critic,PPOC)算法,可以保证下层策略的多样性。为了验证算法的有效性,把MIOOC算法和几种常见的强化学习方法在连续实验环境中进行对比实验。实验结果表明,MIOOC算法可以加快模型学习速度,实验性能更优,Option内部策略更有区分度。 展开更多
关键词 深度强化学习 时序抽象 分层强化学习 互信息 内部奖励 Option多样性
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Pricing Catastrophe Options with Credit Risk in a Regime-Switching Model
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作者 XU Yajuan WANG Guojing 《应用概率统计》 CSCD 北大核心 2024年第4期572-587,共16页
In this paper,we consider the price of catastrophe options with credit risk in a regime-switching model.We assume that the macroeconomic states are described by a continuous-time Markov chain with a finite state space... In this paper,we consider the price of catastrophe options with credit risk in a regime-switching model.We assume that the macroeconomic states are described by a continuous-time Markov chain with a finite state space.By using the measure change technique,we derive the price expressions of catastrophe put options.Moreover,we conduct some numerical analysis to demonstrate how the parameters of the model affect the price of the catastrophe put option. 展开更多
关键词 PRICING catastrophe option credit risk REGIME-SWITCHING measure change
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Unroofed coronary sinus,left-sided superior vena cava and mitral insufficiency:A case report and review of the literature
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作者 Fouad Bitar Ziad Bulbul +4 位作者 Yehya Jassar Rana Zareef Jennifer Abboud Mariam Arabi Fadi Fouad Bitar 《World Journal of Cardiology》 2024年第10期595-603,共9页
BACKGROUND Unroofed coronary sinus(UCS)is a rare subtype of atrial septal defect.It is frequently associated with a persistent left superior vena cava and is often part of a more intricate cardiac malformation.CASE SU... BACKGROUND Unroofed coronary sinus(UCS)is a rare subtype of atrial septal defect.It is frequently associated with a persistent left superior vena cava and is often part of a more intricate cardiac malformation.CASE SUMMARY This report describes a rare case of an adolescent patient with UCS featuring atrial situs solitus,absence of the right superior vena cava and a persistent left superior vena cava draining into the left atrium consistent with total unroofing of the coronary sinus.This was associated with concurrent severe mitral insufficiency secondary to redundant and prolapsing leaflets,and a substantial left-to-right shunt across the coronary sinus orifice.A comprehensive examination of the existing literature is included,shedding light on the diagnostic challenges of UCS and describing the available surgical options within the context of mitral valve surgery.CONCLUSION UCS is a complex condition requiring careful consideration of associated anomalies and a tailored surgical approach. 展开更多
关键词 Unroofed coronary sinus Mitral insufficiency Single left superior vena cava Surgical options Absent right superior vena cava Case report
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Exploring the limited use of transdermal medications in psychiatry:Challenges and potential solutions
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作者 Mandeep Kaur Meera Patel Elizabeth Monis 《World Journal of Methodology》 2024年第4期18-22,共5页
Transdermal medications are an useful yet underutilized tool in the field of psychiatry.Despite numerous advantages of using this route of medication delivery,transdermal medications remain less popular compared to ot... Transdermal medications are an useful yet underutilized tool in the field of psychiatry.Despite numerous advantages of using this route of medication delivery,transdermal medications remain less popular compared to other routes of medication administration such as oral and intramuscular routes in the management of various psychiatric conditions.In this editorial,we examine the advantages of transdermal medications with a brief overview of transdermal being used in psychiatry and other medical specialties.We discuss the factors that play a role in their limited usage in psychiatry.We highlight certain patient categories who can specifically benefit from them and discuss potential solutions that can broaden the perspective of treating clinicians making this an intriguing avenue in the field of psychiatry. 展开更多
关键词 Transdermal medications Psychiatric medications PSYCHOPHARMACOLOGY Treatment options Potential solutions
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Modeling the Spatio-Temporal Dynamics of Local Context for a Contextualized Diffusion of Agroecological Intensification Options in Niger
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作者 Nouhou Salifou Jangorzo Maud Loireau +3 位作者 Abou-Soufianou Sadda Ousmane Sami Mari Abdoul-Aziz Saïdou Hassane Bil-Assanou Issoufou 《International Journal of Geosciences》 CAS 2024年第3期270-301,共32页
Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view ... Spatio-temporal variability and dynamics in Sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, Dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development. 展开更多
关键词 NIGER Option by Context Local Condition Complex System Multiscale Conceptual Modeling
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Type 2 diabetes in children and adolescents:Exploring the disease heterogeneity and research gaps to optimum management
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作者 Subhodip Pramanik Sunetra Mondal +1 位作者 Rajan Palui Sayantan Ray 《World Journal of Clinical Pediatrics》 2024年第2期80-99,共20页
Over the past 20 years,the incidence and prevalence of type 2 diabetes mellitus(T2DM)in children and adolescents have increased,particularly in racial and ethnic minorities.Despite the rise in T2DM in children and ado... Over the past 20 years,the incidence and prevalence of type 2 diabetes mellitus(T2DM)in children and adolescents have increased,particularly in racial and ethnic minorities.Despite the rise in T2DM in children and adolescents,the pathophysiology and progression of disease in this population are not clearly understood.Youth-onset T2DM has a more adverse clinical course than is seen in those who develop T2DM in adulthood or those with T1DM.Furthermore,the available therapeutic options are more limited for children and adolescents with T2DM compared to adult patients,mostly due to the challenges of implementing clinical trials.A better understanding of the mechanisms underlying the development and aggressive disease phenotype of T2DM in youth is important to finding effective prevention and management strategies.This review highlights the key evidence about T2DM in children and adolescents and its current burden and challenges both in clinical care and research activities. 展开更多
关键词 Type 2 diabetes mellitus Children and adolescents PATHOPHYSIOLOGY HETEROGENEITY COMPLICATIONS Treatment options Barriers
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Research on Value Evaluation Method of Investment Project Based on Fuzzy Composite Real Options
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作者 Huanyu Li 《Economics World》 2024年第1期24-34,共11页
Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation ... Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation methods like comparison,proportion,maturity,internal rate of return,scenario analysis,decision trees,and net present value cannot fully consider the uncertainty and stage characteristics of the project.The fuzzy real options method addresses this by combining real option theory,fuzzy number theory,and composite option theory to provide a more accurate and objective evaluation of Public-Private Partnership(PPP)projects.It effectively considers the interaction of options and the ambiguity of project parameters,making it a valuable tool for project evaluation in the context of venture capital investment. 展开更多
关键词 real option fuzzy method Geske composite option
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基于TCP Options Address的客户端真实IP获取的设计与实现
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作者 张会奇 《微型计算机》 2024年第12期37-39,共3页
在代理服务器场景下获取客户端的真实IP地址是非常常见的需求。但通常代理服务器会隐藏客户端的真实IP地址,这对真实IP地址的获取增加了困难。当前一些应用层协议,例如HTTP协议、Proxy protocol协议可以实现客户端真实IP地址的获取,但... 在代理服务器场景下获取客户端的真实IP地址是非常常见的需求。但通常代理服务器会隐藏客户端的真实IP地址,这对真实IP地址的获取增加了困难。当前一些应用层协议,例如HTTP协议、Proxy protocol协议可以实现客户端真实IP地址的获取,但都存在一些弊端,如都需要修改上游服务器的应用层程序。基于TCP Options Address,将数据包从内核态映射到用户态修改,不涉及上游服务器程序的变动,即可得到客户端真实IP地址。 展开更多
关键词 代理服务器 上游服务器 IP地址 TCP Options Address 内核态 用户态
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面向Option的k-聚类Subgoal发现算法 被引量:8
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作者 王本年 高阳 +2 位作者 陈兆乾 谢俊元 陈世福 《计算机研究与发展》 EI CSCD 北大核心 2006年第5期851-855,共5页
在学习过程中自动发现有用的Subgoal并创建Option,对提高强化学习的学习性能有着重要意义.提出了一种基于k-聚类的Subgoal自动发现算法,该算法能通过对在线获取的少量路径数据进行聚类的方法抽取出Subgoal.实验表明,该算法能有效地发现... 在学习过程中自动发现有用的Subgoal并创建Option,对提高强化学习的学习性能有着重要意义.提出了一种基于k-聚类的Subgoal自动发现算法,该算法能通过对在线获取的少量路径数据进行聚类的方法抽取出Subgoal.实验表明,该算法能有效地发现所有符合要求的Subgoal,与Q-学习和基于多样性密度的强化学习算法相比,用该算法发现Subgoal并创建Option的强化学习算法能有效提高A-gent的学习速度. 展开更多
关键词 分层强化学习 OPTION 子目标
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动态环境中的分层强化学习 被引量:5
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作者 沈晶 程晓北 +2 位作者 刘海波 顾国昌 张国印 《控制理论与应用》 EI CAS CSCD 北大核心 2008年第1期71-74,共4页
现有的强化学习方法都不能很好地处理动态环境中的学习问题,当环境变化时需要重新学习最优策略,若环境变化的时间间隔小于策略收敛时间,学习算法则不能收敛.本文在Option分层强化学习方法的基础上提出一种适应动态环境的分层强化学习方... 现有的强化学习方法都不能很好地处理动态环境中的学习问题,当环境变化时需要重新学习最优策略,若环境变化的时间间隔小于策略收敛时间,学习算法则不能收敛.本文在Option分层强化学习方法的基础上提出一种适应动态环境的分层强化学习方法,该方法利用学习的分层特性,仅关注分层任务子目标状态及当前Option内部环境状态的变化,将策略更新过程限制在规模较小的局部空间或维数较低的高层空间上,从而加快学习速度.以二维动态栅格空间内两点间最短路径规划为背景进行了仿真实验,实验结果表明,该方法策略学习速度明显高于以往的方法,且学习算法收敛性对环境变化频率的依赖性有所降低. 展开更多
关键词 分层强化学习 动态环境 OPTION 策略更新
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基于可中断Option的在线分层强化学习方法 被引量:4
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作者 朱斐 许志鹏 +2 位作者 刘全 伏玉琛 王辉 《通信学报》 EI CSCD 北大核心 2016年第6期65-74,共10页
针对大数据体量大的问题,在Macro-Q算法的基础上提出了一种在线更新的Macro-Q算法(MQIU),同时更新抽象动作的值函数和元动作的值函数,提高了数据样本的利用率。针对传统的马尔可夫过程模型和抽象动作均难于应对可变性,引入中断机制,提... 针对大数据体量大的问题,在Macro-Q算法的基础上提出了一种在线更新的Macro-Q算法(MQIU),同时更新抽象动作的值函数和元动作的值函数,提高了数据样本的利用率。针对传统的马尔可夫过程模型和抽象动作均难于应对可变性,引入中断机制,提出了一种可中断抽象动作的Macro-Q无模型学习算法(IMQ),能在动态环境下学习并改进控制策略。仿真结果验证了MQIU算法能加快算法收敛速度,进而能解决更大规模的问题,同时也验证了IMQ算法能够加快任务的求解,并保持学习性能的稳定性。 展开更多
关键词 大数据 强化学习 分层强化学习 OPTION 在线学习
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