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11.
标准物质在分析测试中的重要地位及发展前景 总被引:2,自引:0,他引:2
标准物质在分析测试领域中无论在定值,方法的研究,误差确定等方面都有着重要地位。标准物质的质量保证及正确使用也应引起我们重视。随着科学技术迅速发展标准物质有着广阔发展前景。 相似文献
12.
可持续发展战略指导下的轨道交通规划与评价 总被引:9,自引:0,他引:9
提出了轨道交通规划与评价在实施可持续发展战略过程中需要研究的问题,研究重点是轨道交通规划与评价方法体系和环境对策,研究了轨道交通规划目标的变化、轨道交通规划优化决策理论与方法、轨道交通规划中的环境影响评价、城市轨道交通网络的合理规划、城际轨道交通——客运专线/高速铁路线路基本走向的规划、轨道交通规划可持续发展的评价指标体系概念框架、轨道交通系统可持续发展的能力建设问题等,并通过实例验证了所建立的理论方法体系和模型体系;不仅进行了有关理论和方法的探讨,而且以面向实际应用为目标,开发了相应的软件系统,为轨道交 相似文献
13.
M. Lipow 《Quality and Reliability Engineering International》1985,1(1):27-35
This paper presents a demonstration of a methodology for fault removal during software development. The methodology encompasses the entire development history, from system and software requirements generation to system test. Thus it considers not only the faults during software testing after formal configuration controls have been invoked, but also the faults discovered prior to that phase: during system and software requirements generation, preliminary design, detailed design and code and unit testing. The agents for fault discovery used in verification and validation are called activities, techniques and tools (AT & Ts) in this paper, each having a certain maximum potential or capability for fault discovery. The AT & Ts considered include the usual specification review activities, and also certain tools not normally applied in ‘standard’ software development, such as automated requirements aids. Application of the methodology yields numbers of residual faults as of each phase of development, including those remaining to be discovered during operations and maintenance. Some previous experience and data on residual faults correspond to these results, indicating that the methodology and choice of parameters are reasonable. The methodology also allows one to calculate a relative loss due to delay in fault discovery, which, as is well known, rises rapidly when faults are not discovered during the phase in which they are generated. 相似文献
14.
简述了我国钨矿业概况、现有采选技术水平及钨矿加工利用率 ;从资源配置出发 ,阐述了钨矿业发展存在的几个主要问题 ,并且针对性地提出了可持续发展的几点建议。 相似文献
15.
肖起清 《机械工业高教研究》2008,(2):34-37
大学在办学资源、办学过程、办学质量、办学形象的竞争中出现大量的不良倾向。大学的不良竞争是由于政府主导资源配置、资源和制度供给不足、大学系统重构等因素导致。必须通过控制主体、控制手段的转变和控制对象的发展形成新的控制机制,以保证大学竞争的秩序化和规范化。 相似文献
16.
向春 《机械工业高教研究》2008,(3):85-89
校园文化看不见、摸不着,却支撑着大学的脊梁,它潜移默化影响和造就一所大学的文化品格。它不仅对大学发展起着重要作用,也是大学发展的重要内容,是大学建设的题中应有之义。为此,需要建设民主和谐,具有学术自由、人文精神和创新精神的校园文化,并将它提高到学校战略发展的高度来看,以校园文化整合学校发展战略。 相似文献
17.
Software plays an increasingly important role in modern safety-critical systems. Although, research has been done to integrate software into the classical probabilistic risk assessment (PRA) framework, current PRA practice overwhelmingly neglects the contribution of software to system risk. Dynamic probabilistic risk assessment (DPRA) is considered to be the next generation of PRA techniques. DPRA is a set of methods and techniques in which simulation models that represent the behavior of the elements of a system are exercised in order to identify risks and vulnerabilities of the system. The fact remains, however, that modeling software for use in the DPRA framework is also quite complex and very little has been done to address the question directly and comprehensively. This paper develops a methodology to integrate software contributions in the DPRA environment. The framework includes a software representation, and an approach to incorporate the software representation into the DPRA environment SimPRA. The software representation is based on multi-level objects and the paper also proposes a framework to simulate the multi-level objects in the simulation-based DPRA environment. This is a new methodology to address the state explosion problem in the DPRA environment. This study is the first systematic effort to integrate software risk contributions into DPRA environments. 相似文献
18.
Simonetta Balsamo Vittoria De Nitto Person Paola Inverardi 《Performance Evaluation》2003,51(2-4):269-288
A review is carried out on how queueing network models with blocking have been applied so far into the performance evaluation and prediction of Software Architectures (SA). Queueing network models with finite capacity queues and blocking have recently been introduced and applied as more realistic models of systems with finite capacity resources and population constraints. Queueing network models have been often adopted as models for the evaluation of software performance. Starting from our own experience, we observe the need of a more accurate definition of the performance models of SA to capture some features of the communication systems. We consider queueing networks with finite capacity and blocking after service (BAS) to represent some synchronization constraints that cannot be easily modeled with queueing network models with infinite capacity queues. We investigate the use of queueing networks with blocking as performance models of SA with concurrent components and synchronous communication. Queueing theoretic analysis is used to solve the queueing network model and study the synchronous communication and performance of concurrent software components. Our experience is supported by other approaches that also propose the use of queueing networks with blocking. Directions for future research work in the field are included. 相似文献
19.
This paper considers the integration of alternative technical systems (TS) belonging to a wider class of competing TS, into a supersystem. The paper introduces the notion of alternative TS, shows the peculiarities of their incorporation into a supersystem, reveals the mechanisms used for such incorporation, and shows areas of application for the suggested method. 相似文献
20.