Industrial Machine Systems Risk Assessment: A Critical Review of Concepts and Methods

Reducing the risk of work-related death and injury to machine operators and maintenance personnel poses a continuing occupational safety challenge. The risk of injury from machinery in U.S. workplaces is high. Between 1992 and 2001, there were, on average, 520 fatalities per year involving machines and, on average, 3.8 cases per 10,000 workers of nonfatal caught-in-running-machine injuries involving lost workdays. A U.S. task group recently developed a technical reference guideline, ANSI B11 TR3, "A Guide to Estimate, Evaluate, & Reduce Risks Associated with Machine Tools," that is intended to bring machine tool risk assessment practice in the United States up to or above the level now required by the international standard, ISO 14121. The ANSI guideline emphasizes identifying tasks and hazards not previously considered, particularly those associated with maintenance; and it further emphasizes teamwork among line workers, engineers, and safety professionals. The value of this critical review of concepts and methods resides in (1) its linking current risk theory to machine system risk assessment and (2) its exploration of how various risk estimation tools translate into risk-informed decisions on industrial machine system design and use. The review was undertaken to set the stage for a field evaluation study on machine risk assessment among users of the ANSI B11 TR3 method.     

On the application of statistical learning approaches to construct inverse probability weights in marginal structural Cox models: Hedging against weight-model misspecification

The marginal structural Cox model (MSCM) estimates can be highly sensitive to weight-model misspecification. We assess the performance of various popular statistical learners, such as LASSO, support vector machines, CART, bagged CART, and boosted CART, in estimating MSCM weights. When weight-models are misspecified, we find that the weights computed from boosted CART generally lead to less MSE and better coverage for the MSCM estimates. This study is motivated by the investigation of the impact of beta-interferon treatment on disability progression in subjects with multiple sclerosis from British Columbia, Canada (1995–2008).     

An approximate summarization method of process data for acquiring knowledge to improve product quality

This paper describes a machine learning approach for a manufacturing database. The method is presented in the Nb-Ti superconducting wire domain. A Nb-Ti superconducting wire is produced by iterating the drawing and heat treatment operations. The purpose is to obtain approximate summarization of process data that describes how a production schedule can be improved for better product quality. The method consists of the following steps: First, define a ranking function for a production schedule. Then, generate 'positive' and 'negative' instances for improving a production schedule by comparing a pair of schedules and their ranking values in the database. Using a machine learning technique, called 'ID3', a 'modification patterns' are obtained that generalize the data for better production quality. The final step is to extract approximate information from the induced patterns, which is both desirable for easier understanding by human experts and necessary to avoid being too much influenced by excessive details or disturbances. Two criteria are proposed, correctness and applicability indices, for this approximation.     

蛋白质中钙离子结合残基的识别

钙结合蛋白在诸多重要的生命进程中实现着不可替代的生物学功能。而这些功能的实现,均取决于蛋白质中配体结合残基与钙离子的相互作用。因此,对蛋白质中钙离子结合残基的识别是理解这种重要分子机制的有效手段。建立了396条非冗余蛋白质链共包含1952个钙离子结合残基的钙离子结合蛋白数据集,通过统计分析确定以17个氨基酸残基作为最佳片段长度。使用10交叉检验,以氨基酸组分为特征参数的离散增量算法的预测精度为62.4%,相关系数为0.25;以位点氨基酸保守性信息为特征参数的矩阵打分算法的预测精度为69.9%,相关系数为0.40;以离散增量值、矩阵打分值和自协方差值为特征参数的支持向量机算法的预测精度为75.0%,相关系数为0.50。     

关于多媒体教学的探讨——以《机械工程材料》课程为例

随着高等学校教学改革的不断深入,教学方法逐渐多样化,多媒体教学得到了越来越广泛的应用,结合《机械工程材料》课程,就多媒体课件的制作提出一些看法,认为要做好一个多媒体课件,必须选取用合适的课件制作软件,在熟悉教学内容的基础上,将软件与教学内容有机结合,这样才能收到良好的教学效果。     

浅谈心理学原理在企业安全管理中的科学应用

企业实现生产安全主要取决于人的安全行为和物的安全环境,而人的安全行为与人的安全心理密切相关.因此在企业安全管理的实际工作中,抓住人这一关键环节,科学应用心理学原理通过激励、培养、培训等有效手段,从而激发人的主观能动性,在意识上、行为上由被动参与转变为主动参与,使安全工作做到有预见性和主动性,企业安全管理才会达到更加条理化、系统化、科学化.     

机械设计对CAD的需求

本文论述了现代机械设计对CAD各方面的需求     

对支持向量机混合核函数方法的再评估

混合核函数方法并没有解决核函数的选择问题,只是将问题等价转换为权重参数的选择。同时该方法还需要分别为两个核函数确定参数,大大增加了算法的复杂程度,限制了支持向量机的泛化能力。事实上,调节核函数的参数对分类结果的影响要远大于选择什么类型的核函数,因此混合核函数方法实属“避轻就重”。实证分析表明,不同核函数对应的共同支持向量比例很高,存在很大程度的一致性,线性组合的意义并不大,这也是混合核函数方法无法有效提升分类性能的一个重要原因。     

大数据时代统计学重构研究中的几个热点问题

随着新兴科学技术的迅猛发展,我们目前正面临大数据时代。大数据是“未来的新兴石油”,它必将对未来的科技与社会经济的发展产生深远影响。认识大数据这个崭新的概念是一个逐步深化的过程,有必要将对其研究上升为国家意志,因为大数据将深刻影响人类的决策模式和社会经济的运行模式,将发展成为一个极具潜力新兴产业,最终成为解决中国社会经济、政治转型期的重要手段。 迄今为止,能借助的国内外文献不多,虽然国内很多研究工作者希望尽早进入相关的大数据研究领域,却无从下手。为此,本文前瞻性地介绍当今大数据统计学理论研究中的几个热点问题,以期能有更多的他人后续研究。     

对“机器是不可以被骗的”的批判

＂机器是不可以被骗的＂是基于法律分析方法的错误,引起了就机器是否可以被骗的肯定论和否定论的无意义的长期争论,进而强化了法律分析方法的错误,其作用也随着国外计算机诈骗罪立法和我国司法解释的发展而消失,而利用传统的标准完全可以区分盗窃和诈骗,即行为人取得财产是否由能够处分财产的人因为受骗并基于由被骗所致的认识错误而作出的处分行为所致,因而应该立即抛弃这一观点。