Instruction-Level Fault Tolerance Configurability

Due to modern technology trends such as decreasing feature sizes and lower voltage levels, fault tolerance (FT) is becoming increasingly important in computing systems. Several schemes have been proposed to enable a user to configure the FT at the application level, thereby enabling the user to trade stronger FT for performance or vice versa. In this paper, we propose supporting instruction-level rather than application-level configurability of FT, since different parts of some applications (e.g., multimedia) can have different reliability requirements. Weak or no FT will be applied to less critical parts, resulting in time and/or resource gains. These gains can be used to apply stronger FT techniques to the more critical parts; hence increasing the overall reliability. The paper shows how some existing FT techniques can be adapted to support instruction-level FT configurability, how a programmer can specify the desired FT level of the instructions, and how the compiler can manage it automatically. A comparison between the existing FT scheme EDDI (which duplicates all instructions) and the proposed approach is performed both at the kernel and at full application levels. The simulation results show that both the performance and the energy consumption are significantly improved (up to 50% at the kernel and up to 16% at full application level), while the fault coverage depends on the application. For the full application (JPEG encoder), our approach is only applied to one kernel in order to avoid increasing the programming effort significantly.

支持ERP模型输出的可配置文档生成器

在建立ERP业务模型之后，需要将其进行文档化输出，以协助ERP系统设计与开发人员理解模型并快速开发系统．分析了ERP模型的文档化需求，提出了一种基于页结构的ERP文档模型，建立文档与ERP模型之间的映射关系，并提出了基于XML的文档描述语言DDL。在此基础上，设计了一种文档生成器，通过标准文档模板配置以满足文档格式与内容的个性化需求，通过将ERP模型数据自动写入标准模板以自动生成DDL文档和最终Word文档。     

特定风险控制水平下可配置化乳制品追溯平台

为了提高追溯系统的效率、用户体验和利用率等, 提出设计特定风险控制水平下可配置化乳制品追溯平台的方法. 该方法选择与食品风险相关的参数, 包括HACCP(危害分析关键控制点)、风险等级、风险发生可能性、追溯环节和成本选择, 应用二进制相关的数学推导生成这些参数的编码结果, 把该编码结果进行低、中、高三种区间组合进行分析, 并且详细设计追溯系统的可配置功能. 以乳制品为例, 按照企业需求系统提供定制化服务, 追溯系统可根据企业个性化需求进行定制, 解决追溯系统效率、用户体验和利用率等问题. 对不同食品类型追溯平台实施改造与设计, 可以提高企业应用追溯系统的积极性、政府监管效率以及便于消费者查询.     

Supporting configurability and real time in RTD channels

Network communication services that can be configured to customize functionality provide significant advantages over monolithic versions, but can be difficult to construct if the services must also provide real‐time guarantees on message delivery. This paper describes how practical issues related to the combination of configurability and real time have been addressed in real‐time dependable (RTD) channels, a communication abstraction that has been prototyped using the Cactus system. The architecture and implementation of RTD channels are described, including facilities for translating an application's quality of service requirements into configuration‐specific resource requirements, and an admission control architecture that uses system‐wide information to determine whether sufficient resources exist to create new channels. In addition, the results of experiments that demonstrate that the desired channel properties—including real‐time guarantees—are provided for various configurations are presented. Finally, practical problems and lessons learned from implementing RTD channels on the general‐purpose MK 7.3 Mach operating system are discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

面向企业资源计划全生命周期的建模方法及工具

目前应用于企业资源计划系统建模的方法和工具存在较大缺陷。为此，提出了面向企业资源计划全生命周期的建模方法及相应的工具系统，支持企业资源计划系统需求分析、设计、实施等各阶段模型的灵活构造，并通过映射关系实现模型之间的转换与追溯。给出了企业资源计划全生命周期的建模方法支持企业资源计划业务元模型。通过分析企业资源计划全生命周期的建模需求，探讨企业资源计划全生命周期的建模方法的建模体系与建模过程。企业资源计划全生命周期的建模方法采用片段作为模型的基本组织单位，采用内容对象和图形对象作为模型信息的基本组织单位，支持对建模框架和模型内容的动态配置与扩展，并提供了基于可扩展标记语言的模型转换语言，为将模型数据自动转化为输出文档和程序源代码提供了支持手段。     

反射中间件

利用中间件可以对付分布式系统内在的复杂性和异质性，中间件技术面临着新的挑战：如何对付当前分布式环境的另一个内在特性－－动态性。为此，研究了人员进行了反射中间件的研究。文中首先详细描述了反射技术，在这些基础上给出了反射中间件的定义，并指出了在中间件设计中采用反射技术所能带来的好处，对几种典型的反射中间件进行了仔细地分析和比较，最后对进一步的研究方向进行了展望。     

The design and implementation of the exported procedure call

This paper describes the exported procedure call, a mechanism that pushes computation out of the operating system kernel and into user space. It supports a simple, secure model for system extensions. An exported procedure call incurs overhead crossing of the user‐kernel boundary, but once in user space, it has greater security and usability and is significantly simpler than an equivalent kernel operation. This paper demonstrates the capabilities of the exported procedure call by discussing two implementations. One is the Modify‐on‐access (Mona) file system and the other is the Magi device interface. Mona and Magi use the exported procedure call in order to safely execute untrusted or complex system extensions. This paper shows that in situations where raw kernel performance is not paramount, the exported procedure call is desirable. Copyright © 2001 John Wiley & Sons, Ltd.     

基于产品族可变型结构的配置管理研究

根据客户订单需求的多样性和个性化特点，提出了一种基于产品族可变型结构的产品配置模型。依据产品可配置性，给出了基本配置单元、几何可变型配置单元和结构可变型配置单元3种配置单元，建立了配置模型的知识表达方法，分析了结构变型配置单元间的约束关系、配置规则表达及其求解匹配过程，并建立了约束规则和变量条件的配置设计深度优先求解算法，利用质量功能配置建立了客户需求、产品技术指标与配置单元功能模块之间的映射矩阵。最后，通过轿车配置实例验证了该方法的可行性。