【作者】 张健；

【导师】 曾广周；

【作者基本信息】 山东大学 ， 计算机应用技术， 2012， 博士

【摘要】 Agent理论和技术源于分布式人工智能(DAI),然后从DAI中分离出来,逐渐应用到其它研究领域。在软件工程领域,agent技术作为开发软件系统的新方法得到广泛关注；Agent是位于特定环境中的一个被封装的计算机系统,它具有为完成设计目标而自治、灵活的行为能力；Agent作为一种系统级的、粗粒度的、自治的、灵活的新抽象,为分析、设计复杂软件系统提供了一个崭新的途径,被誉为软件开发的又一重大突破。Agent技术表示了一种计算的社会范型,基于社会学思想研究agent是agent技术发展的必然趋势。基于社会学思想的agent研究工作分为形式化方法和非形式化方法：(1)形式化方法研究社会心智状态和它们之间的相互关系,并使用这些社会心智状态和数理逻辑建立agent模型。形式化方法存在逻辑证明困难、符号操作复杂和实现困难等主要问题；(2)非形式化方法基于社会组织、社会角色等构造agent和多agent系统,使用文字、图、表等描述过程和模型。非形式化方法存在尚未建立人类社会范型并将社会范型映射到多agent系统、尚未分析构造的agent模型是否具备自治性、灵活性等主要问题。本文基于社会角色形成、扮演理论,以agent非形式化方法为对象,研究了基于角色的社会范型和多agent系统模型、agent角色模型、agent自治结构和自底向上的多agent系统构造方法,具体工作和创新点如下。1.研究工作。(1)研究社会角色和基于角色的多agent系统模型。根据社会角色形成、扮演理论,概括了社会角色具有的非先天性、非孤立性、模式性、关系二元性、扮演单一性等五个特征,建立了基于角色的人类社会范型；通过人类社会与多agent系统的概念映射,定义了基于角色的多agent系统模型,包括初始环境、计算环境、角色、agent、角色交互、角色组织等模型；给出了基于角色的多agent系统的构造原则：①agent构造分为在初始环境的自治性构造和计算环境的灵活性构造两步过程；②agent交互模型在计算环境中通过角色关系进行构造；③agent组织在计算环境中构造,通过目标自底向上的动态构造由角色构成的agent组织。讨论了影响多agent系统构造需求变化的因素,如资源因素、agent因素、软件技术因素等。(2)研究agent角色模型和基于角色的agent结构。分析了agent角色研究现状和存在的问题,将agent角色定义为位于同一外部环境中agent个体间的相互关系,将关系数据理论用于agent角色研究；用关系代数定义agent角色形式化模型,包括数据结构、角色操作和角色完整性,角色模型具备的性质表明角色满足软件工程要求的模块化、高内聚、低耦合的设计原则；把角色间的关系定义为角色依赖,使用Armstrong公理研究基于角色依赖的角色规范化,讨论了角色导出、传递等依赖形式,证明了文中的角色依赖集是完备集。定义了角色交互模型,基于事务理论讨论了交互模型具有的自治性、一致性、持久性特征。定义了角色组织模型,分析了组织模型的动态性和灵活性。用Pi演算描述了基于角色的agent模型的构成模块和模块交互,分析了角色扮演过程。(3)研究基于反馈机制的agent自治BDI结构。模拟人类个体自治状态、自治功能和自治控制,建立基于反馈机制的agent自治BDI结构。人的自治状态表现为内环境中各项因素数据,按照处理对象,把人的生理功能概括为六个系统：外部资源处理系统、防护系统、控制系统、感受系统、效应系统、其它系统。建立了人类个体自治状态、自治系统、自治控制与BDI模型间的映射关系,使用Pi演算描述了自治agent BDI结构的构成模块、模块间的交互关系和交互信息,对模型运行过程分析证明结构能通过反馈机制控制内部状态和行为,具备自治性。(4)研究自底向上的多agent系统分析和设计方法。给出了agent模型技术方法(AMT)。AMT基于对象模型技术(OMT)的过程和模型表示方法AMT包括分析和设计两个阶段：①分析阶段建立领域模型、Agent模型、角色模型、交互模型和功能模型。领域模型使用领域工程方法建立,用于描述agent位于的外部环境,获得外部环境的共性特征和变化性特征,其中共性特征描述了agent自治属性和操作；Agent模型描述系统的静态结构,agent模型由类图表示；角色模型描述了agent间的关系,实现agent灵活性；交互模型表明了agent的动态行为,通过描述agent的角色行为脚本,建立每个agent的状态图,所有agent的状态图构成交互模型；功能模型由数据流图表示,它表示了功能的输入输出值；Agent操作由交互模型和功能模型中获得。②AMT设计阶段进行领域设计、agent设计和组织设计,领域设计确定agent自治结构、功能算法等,agent设计把自治功能、自治属性和角色封装在一起：组织设计确定组织内的agent、角色,识别处理组织内部、组织之间的并发性,设计数据存储结构等。2.本文的创新点。(1)基于社会学角色理论,建立了一种基于角色的多agent系统模型。本文建立的基于角色的多agent系统模型,突出了社会个体在社会环境中的作用。相对于那些根据角色概念直接建立的多agent系统模型,本文模型能够更好地刻画agent作为社会角色的特征,体现多agent系统的社会性和可组织性。(2)基于关系代数理论,建立了一种agent角色的形式化模型。本文建立的agent角色形式化模型,突出了角色关系和角色依赖在agent构造中的作用。相对于那些仅基于角色概念定义的角色模型,本文模型具备更为明确的边界和更为清晰的语义,更利于agent构造和复用。(3)基于Pi演算,建立了一种基于反馈的自治agent BDI结构。本文建立的自治agent BDI结构,突出了反馈机制在保持自治信念、自治愿望、自治意图中的平衡作用。相对于通用型的BDI结构,本文建立的自治agentBDI结构,限定了可能世界语义范围,结构简洁,构建方便。Agent技术是较新的研究领域,无论是理论研究还是应用方面都还有许多工作要做。本文研究了agent角色与多agent系统构造方法中的一些基础性的内容,在本文研究工作基础上的进一步的工作包括：(1)研究多agent系统自治性。在本文agent个体BDI自治结构的基础上,基于社会组织理论,研究什么是多agent系统的自治状态、自治行为,实现多agent系统的自治性合适结构和机制；(2)研究agent多角色依赖。在本文agent角色依赖研究的基础上,研究什么是agent多角色依赖,多角色依赖的形式化表示和规范化问题；(3)Agent模型技术方法的软件质量度量问题研究。本文仅给出了方法的非形式化过程描述,未进一步使用软件工程度量方法讨论agent模型技术构造的agent系统的质量。更多还原

【Abstract】 Agent theory and technology derived from distributed artificial intelligence, and then was broadly used in other research fields. Agent technology as a new software development method has been gotten more and more attention. As a new abstract with system level, coarse grained, autonomy and flexible, agent provides a brand-new way for analysis and design of complex software, and is called a important breakthrough of software development. Agent technology express a society computing paradigm, so the agent study based on sociology thinking is tendency of agent technology. Agent model and construction based on sociology thinking has formal method and informal method:(1) The formal method studies social mental status and their relationship, use these mental status and mathematical logic to construct social agent model, it has some main problems, such as logic proving difficult, symbolic operation complexity, achievement difficult, etc.(2) The informal method construct agent model based on social organization, social role, etc, and use word, picture, and chart to describe agent model; it has some main problems, such as what is human society paradigm, what is multi agent system model based on social thinking and suitable construction principle of agent, how to construct agent with autonomy and flexible properties, etc. Based on understanding about sociology and social role forming and action theory, this paper uses informal method as study object, studies multi agent system model based on role, agent role model, agent autonomy architecture and agent model technology based on bottom-up way.The main works of this paper are described as follows:1. Study of social role and multi agent model based on role. According to social role forming and action theory, this paper thinks the social role is key line in sociology, summary five features of social role:non-congenital, non-isolated, pattern, duality relationship and single action, establishes human society paradigm based on social role. Through establishment mapping between human society and multi agent system, this paper defines multi agent system model based on role, it includes initial environment, compute environment, role, agent, role interaction, role organization; gives construction principle of multi agent system model based on role:(1) the agent construction has two step, one step constructs autonomy in initial environment, the other step constructs flexible in compute environment;(2) agent interaction model is constructed by role relationship in compute environment;(3) agent organization is constructed by role using bottom-up way according to organization goal. Discussion influencing factors about requirement construction changes of multi agent system, such as resources, agents, software technology, etc.2. Study of agent role and agent architecture based on role. This paper discusses present and main problems about agent role study, bring forward that an agent role is a relationship between agents locate in same environment, and use relational data theory study agent role; use relational algebra to define role formal model, it includes role data structure, role operation and role integrity, and properties of role model indicate that role satisfy module, high cohesion, low coupling; define relationship among role as role dependent, use Armstrong axiom to study role normalization based on role dependent, discuss transitive dependent and derived dependent, and prove role dependent set is a complete set; define role interaction model, discuss autonomy, consistency and persistent properties of role interaction based on transaction theory; define role organization model, analysis dynamic and flexible of role organization; use Pi calculus define a agent architecture based on role, analysis process of role action.3. Study of agent autonomy BDI architecture based on feedback. This paper establishes agent autonomy BDI architecture through simulation autonomy system of human being. The autonomy status of individual is factors in inside environment, summary physiological functions as six systems:external resource operation system, protection system, control system, sense system, effect system and others; establishes mapping between individual autonomy system and BDI model, uses Pi calculus define agent autonomy BDI architecture, analysis about running indicate architecture can achieve autonomy based on feedback, can control inside status and action by itself. 4. Study of agent analysis and design method using bottom-up way. This paper gives agent model technology (AMT). AMT is based on process and model expression of object model technology. AMT has analysis and design two stages:(1) The analysis stage establishes domain model, agent model, role model, interaction model and function model. The domain model is established by domain engineering method, describes environment where agents locate, gain common feature and diversification feature, the common feature define autonomy properties and operations. The agent model describes static structure of MAS, and use class diagram express agent model. The role model describes relationship among agents, and achieve flexible. The interaction model expresses dynamic feature of agent, define script of role action, then gain status diagram of agent, all status diagram compose interaction model. The function model is defined by data flow diagram, and it expresses output value of agent. The operation of agent is gained from interaction and function model.(2) The design stage includes domain design, agent design and organization design. The domain design defines autonomy operation algorithm. The agent design encapsulates autonomy operations, autonomy properties and role. The organization design defines roles, agents in organization, determine store data structure, and deal with concurrent inside or outside organization, etc.The main innovations of this paper are described as follows:1. Based on social role theory, this paper establishes a multi agent system model based on role. This model highlights the individual effect in society environment. Compared with other multi agent system models directly defined by social role concept, this model in this paper can better describe the feature about agent as social role, and better indicate social and organization of multi agent system.2. Based on relational data theory, this paper establishes an agent role formal model. This formal model highlights the effect of role relationship and role dependent in construction agent. Compared with other agent models directly defined by social role concept, this agent model has more clearly boundary and semantic, in favor of agent construction and reuse..3. Based on Pi calculus, this paper establishes an agent autonomy BDI architecture based on feedback. This model highlights feedback effect in keeping balance among autonomy belief, autonomy desire and autonomy intention. Compared with general BDI architecture, this model in this paper limit scope of possible world semantic, architecture is concise and can be easily constructed.Agent theory and technology is a new research filed, either theory or application has more works to do. This paper studies foundation contents of agent model and construction method based on social role, the further work includes:1. Study autonomy architecture of multi agent system. Based on autonomy agent BDI architecture in this paper and social organization theory, study what is autonomy status, autonomy action of multi agent system? how to achieve autonomy of multi agent system? etc.2. Study multi role dependent. Based on agent role dependent in this paper, study what is multi role dependent? How to formal express multi role dependent? What is normalization of multi role dependent? Etc.3. Study measure of agent model technology. This paper only gives informal description of agent model technology, don’t use software measure method discussion quality of multi agent system constructed by this technology.更多还原