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101.
In this paper, a method for writing composable TLA+ specifications that conform to the formal model called Masaccio is introduced. Specifications are organized in TLA+ modules that correspond to Masaccio components by means of a trace-based semantics. Hierarchical TLA+ specifications are built from atomic component specifications by parallel and serial composition that can be arbitrary nested.
While the rule of parallel composition is a variation of the classical joint-action composition, the authors do not know about
a reuse method for the TLA+ that systematically employs the presented kind of a serial composition. By combining these two composition rules and assuming
only the noninterleaving synchronous mode of an execution, the concurrent, sequential, and timed compositionality is achieved. 相似文献
102.
103.
人工智能实验教学探讨 总被引:4,自引:3,他引:1
本文一方面简单介绍人工智能的基本理论及知识体系结构,另一方面则结合笔者的理论实践与实验教学经验,总结出目前在整个教学过程所存在的一些问题,目的在于不断总结经验,力争能更好地完成人工智能的整个教学工作,从而提高人才培养的质量,同时也可以为其他高校提供参考。 相似文献
104.
A novel probabilistic fuzzy control system is proposed to treat the congestion avoidance problem in transmission control protocol (TCP) networks. Studies on traffic measurement of TCP networks have shown that the packet traffic exhibits long range dependent properties called self-similarity, which degrades the network performance greatly. The probabilistic fuzzy control (PFC) system is used to handle the complex stochastic features of self-similar traffic and the modeling uncertainties in the network system. A three-dimensional (3-D) membership function (MF) is embedded in the PFC to express and describe the stochastic feature of network traffic. The 3-D MF has extended the traditional fuzzy planar mapping and further provides a spatial mapping among "fuzziness-randomness-state". The additional stochastic expression of 3-D MF provides the PFC an additional freedom to handle the stochastic features of self-similar traffic. Simulation experiments show that the proposed control method achieves superior performance compared to traditional control schemes in a stochastic environment. 相似文献
105.
Yan Wang Kwei-Jay Lin Duncan S. Wong Vijay Varadharajan 《Service Oriented Computing and Applications》2009,3(2):129-146
In service-oriented computing (SOC) environments, service clients interact with service providers for services or transactions.
From the point view of service clients, the trust status of a service provider is a critical issue to consider, particularly
when the service provider is unknown to them. Typically, the trust evaluation is based on the feedback on the service quality
provided by service clients. In this paper, we first present a trust management framework that is event-driven and rule-based.
In this framework, trust computation is based on formulae. But rules are defined to determine which formula to use and what
arguments to use, according to the event occurred during the transaction or service. In addition, we propose some trust evaluation
metrics and a formula for trust computation. The formula is designed to be adaptable to different application domains by setting
suitable arguments. Particularly, the proposed model addresses the incremental characteristics of trust establishment process.
Furthermore, we propose a fuzzy logic based approach for determining reputation ranks that particularly differentiates new
service providers and old (long-existing) ones. This is further incentive to new service providers and penalize poor quality
services from service providers. Finally, a set of empirical studies has been conducted to study the properties of the proposed
approaches, and the method to control the trust changes in both trust increment and decrement cases. The proposed framework
is adaptable for different domains and complex trust evaluation systems.
相似文献
Vijay VaradharajanEmail: |
106.
采用PLC和触摸屏PT组合的方案实现了对生物质热解装置的现场控制。控制程序由手动和自动控制两个部分组成,并且可以根据需要实现它们之间的无痕迹切换。自动控制程序主要由燃烧、冷凝和热解三个子系统组成,其中温度等模拟量的控制根据调试经验采取分段控制的方法。现场运行表明,本系统具有调节灵活、稳定性好、造价低等优点。 相似文献
107.
描述逻辑是语义Web的逻辑基础,是形式化表达领域知识的工具.但是描述逻辑只能表达单调推理,不能处理不完全知识.认知描述逻辑因其非单调特性和良好的时间复杂度等特点在处理不完全知识方面有较好的优势.本文在认知描述逻辑ALCK的基础上提出了新的认知描述逻辑语言ALCKR ,保留了描述逻辑原有的优点,加入传递角色属性,增强了表达能力,并通过认知查询拥有了非单调推理的能力.设计了ALCKR 的语法、语义以及表算法. 相似文献
108.
109.
110.
Anna Bucalo 《Journal of Logic, Language and Information》1994,3(3):211-232
We present a semantic study of a family of modal intuitionistic linear systems, providing various logics with both an algebraic semantics and a relational semantics, to obtain completeness results. We call modality a unary operator on formulas which satisfies only one rale (regularity), and we consider any subsetW of a list of axioms which defines the exponential of course of linear logic. We define an algebraic semantics by interpreting the modality as a unary operation on an IL-algebra. Then we introduce a relational semantics based on pretopologies with an additional binary relationr between information states. The interpretation of is defined in a suitable way, which differs from the traditional one in classical modal logic. We prove that such models provide a complete semantics for our minimal modal system, as well as, by requiring the suitable conditions onr (in the spirit of correspondence theory), for any of its extensions axiomatized by any subsetW as above. We also prove an embedding theorem for modal IL-algebras into complete ones and, after introducing the notion of general frame, we apply it to obtain a duality between general frames and modal IL-algebras. 相似文献