基于区分服务的Web服务器服务质量机制

论文利用近似计算模型和WHC实时调度策略,设计了一个Web服务器能够提供区分服务和服务质量保证PIK机制。同时,通过修改ApacheWeb服务器软件,实现了对PIK机制的仿真研究。通过仿真实验表明,PIK机制是一个可行的和有效的Web服务器区分服务质量机制,它为Web服务器区分服务质量研究提供了模型框架。     

高性能网络服务器框架的研究与实现

为构建面向海量数据和连接的互联网应用服务器,提出一种轻量级的高性能服务器开发框架LHP—Svrframe。除服务器开发框架的常用模块（如网络通信管理、自定义协议开发以及进程处理模型等）外,LHP—Svrframe特别提供针对TCP／IP通信协议和进程模型额外的优化设计,如对NIC网卡中断的负载均衡、拥塞窗口的动态调整、ACK延时机制的改进等。与Apache、Lighttpd、ACE等网络服务器或开发框架的对比结果表明,使用LHP-Svrframe开发的应用服务器在最大连接数和吞吐量上性能可提升4-8倍。     

基于Java的邮件服务器的设计与实现

文章在比较了二层与三层结构模型和多层结构模型之间的异同和优缺点的基础上,提出了一种基于Java的邮件服务器设计方案,并给出了该方案的设计思想和具体实现,剖析了EJB在该邮件服务器(MailServer)中的应用,EJB提供了Java服务器端服务框架的规范,使得设计者可以专注于应用业务逻辑的设计,而不必考虑底层框架的实现,增强了系统的可移植性和可扩展性,并且更易于维护和升级,同时简单分析了邮件服务器的SMTP与POP3协议的设计实现。     

动态聚合权重的隐私保护联邦学习框架

在非可信中心服务器下的隐私保护联邦学习框架中,存在以下两个问题。(1)在中心服务器上聚合分布式学习模型时使用固定的权重,通常是每个参与方的数据集大小。然而,不同参与方具有非独立同分布的数据,设置固定聚合权重会使全局模型的效用无法达到最优。(2)现有框架建立在中心服务器是诚实的假定下,没有考虑中央服务器不可信导致的参与方的数据隐私泄露问题。为了解决上述问题,基于比较流行的DP-Fed Avg算法,提出了一种非可信中心服务器下的动态聚合权重的隐私保护联邦学习DP-DFL框架,其设定了一种动态的模型聚合权重,该方法从不同参与方的数据中直接学习联邦学习中的模型聚合权重,从而适用于非独立同分布的数据环境。此外,在本地模型隐私保护阶段注入噪声进行模型参数的隐私保护,满足不可信中心服务器的设定,从而降低本地参与方模型参数上传中的隐私泄露风险。在数据集CIFAR-10上的实验证明,DP-DFL框架不仅提供本地隐私保证,同时可以实现更高的准确率,相较DP-Fed Avg算法模型的平均准确率提高了2.09%。     

客户／服务器模型

本文介绍了客户／服务器处理模型和基本框架．论述了客户／服务器模型的主要优产、并通过一实例介绍了客户／服务器环境中DBMS体系结构的实现。     

一种基于agent的分布式集成框架的设计与实现

对象框架技术已成为当今分布异构环境下建立应用系统集成和软构件的核心技术,为支持分布式客户/服务器应用的开发和集成,我们开展了分布式集成框架CSE/MA的研究和开发,目的在于提供一种支持分布式客户/服务器应用开发的分布式集成框架.方便用户开发和集成分布式客户/服务器应用。     

IMS 中基于策略QoS 管理模型

IMS（IP多媒体子系统）给客户带来丰富的多媒体体验的同时,也对服务质量（QoS）管理提出了更高的要求,即针对不同用户定制的不同服务,网络运营商应该制定差异化的策略进行QoS管理。3GPP定义了基于策略的QoS管理框架,但这个框架只是逻辑上的架构,没有定义具体物理实施的方案。对基于策略QoS管理模型进行了分析,在参照3GPP定义的标准基础上,提出了一种管理模型的实现方案,设计并实现了该模型中两个关键服务器策略决策服务器（PDF）和策略执行服务器（PEP）。经过测试,两个服务器能互相配合,正确完成查询策略信息,做出策略决策,执行带宽请求预留、QoS等级协商功能,为网络运营商提供了参考。     

带大厅的网络象棋游戏的设计与实现

以设计网络象棋游戏中心为基础,介绍客户大厅和服务器的功能和通讯过程,多线程阻塞式通讯的应用,提供了一个基于tcp连接的多线程客户与服务器的代码框架,该框架可用于棋牌类在线游戏中心的设计。     

基于OPNET的IDS仿真模型研究

针时OPNET平台中缺少入侵检测系统(IDS)仿真模型的现状,在分析IDS工作原理的基础上,提出了IDS仿真模型的三维建模框架.该框架遵循了通用灵活和易于实现的建模原则,以OPNET平台中的工作站模型和服务器模型为开发基础,分别从进程、节点和网络3个层次建立了IDS的仿真模型,并通过仿真实验验证了仿真模型的有效性,从而扩展了OPNET的基础模型库,为基于OPNET的网络安全仿真提供了模型支持.     

直播服务器一般性框架体系设计

基于流媒体服务器设计框架,结合直播服务器本身的功能、特性,并综合考虑波动的网络环境对其的影响,给出一种适用于直播服务器的一般性的实现框架。在这个实现框架中直播服务器由四个功能模块组成:速率控制模块、差错控制模块、质量自适应模块以及缓冲区控制模块。这四个功能模块各自完成特定的功能,并相互协作以使直播服务器系统作为整体提供适应性的视频传输服务。对各功能模块之间的协作和互动关系作了详细的阐述。提出的框架体系可以根据应用需求进行灵活配置以得到适当的实现形式,对开发直播系统具有参考价值。     

Domain-Specific Modeling Languages to improve framework instantiation

Frameworks are reusable software composed of concrete and abstract classes that implement the functionality of a domain. Applications reuse frameworks to enhance quality and development efficiency. However, frameworks are hard to learn and reuse. Application developers must understand the complex class hierarchy of the framework to instantiate it properly. In this paper, we present an approach to build a Domain-Specific Modeling Language (DSML) of a framework and use it to facilitate framework reuse during application development. The DSML of a framework is built by identifying the features of this framework and the information required to instantiate them. Application generators transform models created with the DSML into application code, hiding framework complexities. In this paper, we illustrate the use of our approach in a framework for the domain of business resource transactions and a experiment that evaluated the efficiency obtained with our approach.     

框架技术在证券交易系统设计中的应用

文章在对框架技术进行研究的基础上,论述了设计框架所要解决的问题,并提出了相应的解决方法,最后设计并实现了一个证券交易系统客户子系统的框架。     

基于版本信息的面向对象框架实例化模式挖掘*

基于框架的面向对象开发技术是实现大规模软件复用的一种有效的途径.由于框架本身层次的复杂性,往往导致框架实例化过程的复杂和烦琐,通常采用记录框架变化点的实例化过程和约束条件的方法来解决这个问题.但是,对于那些缺乏详细记录的"遗留"面向对象框架,框架变化点实例化记录往往隐含在具体的实现细节中,从而使得"遗留"面向对象框架的复用变得十分困难.提出了一种基于版本信息获取面向对象框架的实例化模式的方法,从而辅助框架的实例化工作.     

安全属性形式化描述统一框架及其分析方法研究*

在安全协议的形式化分析研究当中,如何在统一的框架下对更多的安全属性进行分析和验证是一个亟待解决的重要问题。为了解决这个问题,本文提出了用匹配关系来形式化地描述各种安全属性的统一框架,建立了语法和语意系统,并证明了该框架的可靠性和完备性。在此基础上,将知识推理和进程演算结合起来,提出了一个安全协议形式化分析的一般模型。最后,给出了一些安全属性的研究实例,并指出了进一步完善此模型的研究方向。     

视频结构挖掘的概念及应用

提出了一种视频结构挖掘的概念框架和视频结构挖掘系统框架,在概念框架中对视频结构挖掘相关概念给出了规范化的定义,视频结构挖掘框架包括的主要内容有视频基本结构挖掘、视频语法结构挖掘和视频语义结构挖掘。最后讨论了视频结构挖掘中发现的结构模式和知识的具体应用,包括指导视频的组织与管理、实现基于内容的个性视频推荐和改善视频摘要系统。     

A Framework for Coordinated Control of Multiagent Systems and Its Applications

In this paper, a framework is proposed for the distributed control and coordination of multiagent systems (MASs). In the proposed framework, the control of MASs is regarded as achieving decentralized control and coordination of agents. Each agent is modeled as a coordinated hybrid agent, which is composed of an intelligent coordination layer and a hybrid control layer. The intelligent coordination layer takes the coordination input, plant input, and workspace input. In the proposed framework, we describe the coordination mechanism in a domain-independent way, i.e., as simple abstract primitives in a coordination rule base for certain dependence relationships between the activities of different agents. The intelligent coordination layer deals with the planning, coordination, decision making, and computation of the agent. The hybrid control layer of the proposed framework takes the output of the intelligent coordination layer and generates discrete and continuous control signals to control the overall process. To verify the feasibility of the proposed framework, experiments for both heterogeneous and homogeneous MASs are implemented. The proposed framework is applied to a multicrane system, a multiple robot system, and a MAS consisting of an overhead crane, a mobile robot, and a robot manipulator. It is demonstrated that the proposed framework can model the three MASs. The agents in these systems are able to cooperate and coordinate to achieve a global goal. In addition, the stability of systems modeled using the proposed framework is also analyzed.     

Combined discrete event and discrete time simulation framework and its application to the block erection process in shipbuilding

In this study, a simulation framework which can support to develop various simulation systems for process planning in shipbuilding is proposed. In addition, a simulation kernel which is a key component of the proposed simulation framework is implemented according to the concept of the combined discrete event and discrete time simulation. To evaluate the efficiency and applicability of the simulation framework proposed in this study, it is applied to the block erection process in shipbuilding. The result shows that the proposed simulation framework can provide the consistent, integrated development environment for a simulation system.     

Fuzzy decision-making framework for treatment selection based on the combined QUALIFLEX–TODIM method

Treatment selection is a multi-criteria decision-making problem of significant concern in the medical field. In this study, a fuzzy decision-making framework is established for treatment selection. The framework mitigates information loss by introducing single-valued trapezoidal neutrosophic numbers to denote evaluation information. Treatment selection has multiple criteria that remarkably exceed the alternatives. In consideration of this characteristic, the framework utilises the idea of the qualitative flexible multiple criteria method. Furthermore, it considers the risk-averse behaviour of a decision maker by employing a concordance index based on TODIM (an acronym in Portuguese of interactive and multi-criteria decision-making) method. A sensitivity analysis is performed to illustrate the robustness of the framework. Finally, a comparative analysis is conducted to compare the framework with several extant methods. Results indicate the advantages of the framework and its better performance compared with the extant methods.     

管理信息系统通用构件框架及其应用

该文在J2EE架构的基础上提出了管理信息系统的通用框架,应用框架可以使管理信息系统领域内的软件结构一致性更好,达到分析重用、设计重用和代码重用的目的。框架中引用了大量的设计模式,充分考虑了系统的可扩展性、可重用性。该文还通过一个具体的应用系统的设计和实现,深入探讨了框架的应用。     

A multi-scale framework for adaptive binarization of degraded document images

In this work, a multi-scale binarization framework is introduced, which can be used along with any adaptive threshold-based binarization method. This framework is able to improve the binarization results and to restore weak connections and strokes, especially in the case of degraded historical documents. This is achieved thanks to localized nature of the framework on the spatial domain. The framework requires several binarizations on different scales, which is addressed by introduction of fast grid-based models. This enables us to explore high scales which are usually unreachable to the traditional approaches. In order to expand our set of adaptive methods, an adaptive modification of Otsu's method, called AdOtsu, is introduced. In addition, in order to restore document images suffering from bleed-through degradation, we combine the framework with recursive adaptive methods. The framework shows promising performance in subjective and objective evaluations performed on available datasets.