基于可靠性屋的维修配置方法

将故障树分析（FTA）、失效模式影响分析（FMEA）整合到质量功能配置（QFD）中,建立了维修配置流程。首先对维修影响因素进行了重要度分析;然后建立了以维修性能目标函数最大和配置成本最低为目标的模型,将维修指标配置到具体的工程技术特征上;最后,以数控车床电主轴为例,验证了配置方法的有效性。     

基于故障树和双向联想记忆神经网络的桥式起重机故障诊断方法

针对桥式起重机的故障诊断系统,提出一种基于故障树(FTA)和双向联想记忆神经网络(BAM)相结合的故障诊断方法。通过FTA建立系统故障树,收集桥式起重机所有故障模式,进而归纳出BAM的学习样本,然后对样本学习联想,得到系统诊断结果。两种方法的结合,不但可完成单个故障的诊断,还可实现多种故障的综合处理,提高诊断能力。     

某增量式数字阀可靠性分析

数字阀作为液压系统的核心部件,一旦发生故障将导致严重后果。为提升数字阀的可靠性,以增量式数字阀的可靠性为研究对象。根据给出的增量式数字阀机械结构和工作原理建立数字阀的可靠性框图,分析得到故障模式和故障机制;建立数字阀故障树模型,进行故障树分析;对故障发生对机构的影响程度进行致命度分析,得到致命性矩阵图。结果表明:数字阀的阀芯不动、阀芯运行卡停、阀芯运行不精确是数字阀工作过程中常见的3种故障,其中阀芯在运行过程中突然卡停是数字阀的致命度中最严重的故障模式。研究成果可为增量式数字阀的结构设计优化和可靠性分析提供一定参考。     

Environmental and life cycle analysis of a biodiesel production line from sunflower in the Province of Siena (Italy)

The Directive 2009/28/EC established the overall target that 20% of energy consumption should be represented by renewable energy sources by 2020 in each European member state. Furthermore, the Directive sets a mandatory 10% minimum target for biofuels in the transport sector.Biofuels are potentially an important alternative to mineral diesel. We propose a pilot production line of biodiesel from sunflower on local scale in the Province of Siena (Tuscany) to research a possible reduction of fossil fuel consumption in the transport sector.This study might represent an opportunity to reduce petroleum dependence in the transport sector.Environmental Impact Indicators were provided by Material Flow Accounting, Embodied Energy Analysis and Emergy Accounting. Results showed that agricultural phase is the critical step in the production line.A comparative Life Cycle Assessment analysis for the biodiesel production line with mineral diesel production showed environmental advantages of the biofuel production, however requiring a higher land demand. Therefore, biodiesel may not the optimal solution on large scale but might be a good alternative to fossil fuel. This would depend upon the entire production cycle taking place in a limited area. This is necessary in order to fulfill the needs of local farms and small enterprises.     

Editor’s introduction.

Following consultation with the Council of Editors and with approval from the Publications and Communications Board of the American Psychological Association (APA), it was agreed that in recognition of the appearance of Volume 100 in 1986, Journal of Comparative Psychology (JCP) would publish a set of discussions about our topic. The discussions, contributed in response to the following letters, written last year, appear in this issue. These discussions illustrate the richness and variety of some of the perspectives on the field of comparative psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparative study of vision tracking methods for tracking of construction site resources

Vision tracking has significant potential for tracking resources on large scale, congested construction sites, where a small number of cameras strategically placed around the site could replace hundreds of tracking tags. The correlation of vision tracking 2D positions from multiple views can provide the 3D position. However, there are many 2D vision trackers available in the literature, and little information is available on which one is most effective for construction applications. In this paper, a comparative study of various vision tracker categories is carried out, to identify which one is most effective in tracking construction resources. Testing parameters for evaluating categories of trackers are identified, and benefits and limitations of each category are presented. The most promising trackers are tested using a database of construction operations videos. The results indicate the effectiveness of each tracker in relation to each parameter of the test, and the most suitable tracker needed to research effective 3D vision trackers of construction resources.     

Identification of new epidemiological molecular markers by comparative proteomics of serogroup A meningococcal isolates from three pandemic waves

We previously described the first reference map for the proteome of one strain of serogroup A Neisseria meningitidis (MenA), a major cause of epidemic meningitis in humans. As a preliminary finding, in that work we noted that 2‐DE protein maps of closely related MenA isolates from different epidemics spreads could be easily compared to detect minor differences and that 2‐DE phenotypes attributable to the well‐known epidemiological marker tbpB agreed with the genoclouds model of MenA epidemiological variation during pandemic waves. We explored here the possibility that an extended comparative study of 2‐DE maps of isolates representative of the nine genoclouds described by Achtman and collaborators could be used to discriminate between strains otherwise undistinguishable. We showed the example of 14 proteins with different 2‐DE spot patterns in different genoclouds that could be considered as putative tracers for alike‐strains discrimination. We introduce the novel concept that comparative proteomics can be useful in identifying new epidemiological markers for N. meningitidis.     

Factors Affecting the Use of Precast Concrete Systems in the United States

The use of precast concrete systems offers several advantages such as speedy erection, higher quality, lower project cost, better sustainability, and enhanced occupational health and safety. In spite of these advantages, the share of precast concrete systems in the U.S. building construction market is very low. The factors behind this low market share are discussed in several studies. This study aims to identify the current factors that affect the use of precast concrete systems, compare them with the ones that prevailed in 1995, and figure out what has changed through the last 11?years in the American precast concrete industry. The findings of an extensive survey indicate that most of the dominating barriers to the extensive use of precast concrete systems in 1995 are either eliminated or drastically reduced, while some of them still prevail. Practitioners should be well informed about the factors that affect the use of precast concrete systems if these systems are to be used more extensively.     

三种经济合理剥采比计算方法评述

储量盈利比较法，费用收入比较法和储量成本比较法在计算内容，计算公式和计算数值各环节上有着密切联系，而在适用条件，经济背景和应用前景等方面又有不同特点。系统的理论研究和算例分析表明，费用收入比较法具有计算原理完善，可操作性好和应用范围广等优点。     

上海地铁车辆一号线制动系统的可靠性分析

介绍上海地铁车辆一号线延长线的制动系统的结构原理，对这种结构的制动系统故障原因进行分析。采用FTA方法对制动系统的可靠性进行了分析，得出导致制动故障的所有可能因素和薄弱环节，为制动系统维修和今后购车选型提供依据。