矿山爆破安全管理的重要度因果分析法

结合改进层次分析法与因果分析图，形成重要度因果分析图，使定性分析问题定量化，并将其应用到爆破安全管理中，为制定确切的爆破于故预防措施提供了高效、便捷的理论和决策依据。     

因果图在不确定度评定中的应用

介绍了因果图的来源及绘制方法,并举例说明其在不确定度评定中的应用。     

用全站仪标定油罐容量的不确定度分析

利用JJG168—2005立式金属罐检定规程规定立式罐各个参数的指标,做不确定度来源分析,计算出立式金属罐容量的标准不确定度和扩展不确定。     

考虑竞争性分析的改进模糊重要度绩效分析方法

重要度绩效分析（IPA）是顾客满意度评价的常用方法,分析结果是产品/服务改进设计的重要依据。）为处理顾客评价信息的不确定性,采用模糊集方法表达并处理重要度和绩效评价信息。针对传统IPA方法中,属性绩效值的获取没有考虑市场竞争因素的问题,提出了考虑竞争性分析的改进模糊IPA方法。灰色关联分析法用来计算属性的市场竞争性系数,以修正顾客群决策得到的初始属性绩效评价值。考虑到属性之间存在影响关系,DEMATEL方法用来分析属性的影响和被影响程度,以修正顾客群决策得到的初始属性重要度评价值。以某电子产品的顾客满意度分析为例,验证了所提方法的有效性。     

基于Meta-SEM的顾客忠诚因果模型研究

利用顾客忠诚领域诸多实证研究的结果,通过元分析(Meta)与结构方程模型(SEM)两种技术相结合,将在对文献数据进行整合的基础上验证顾客忠诚因果关系的整合模型,以期说明顾客忠诚的驱动因素、后果及其作用机理.其中顾客承诺对顾客忠诚的影响最为显著,其次是顾客价值,接下来是顾客信任,顾客满意对顾客忠诚的作用最小.而且转换成本会带来企业绩效的提高,而对顾客忠诚的作用较小.顾客价值不仅有利于顾客忠诚度的提高,而且会直接作用于企业绩效.在影响企业绩效的因素中,顾客价值的影响程度最大,其次是转换成本,再次是顾客忠诚.     

不确定度分析方法在暖通空调实验中的应用

本文介绍了不确定度分析在暖通空调专业的应用方法,并结合传热实验和热值测定实验来阐述总体不确定度分析和详细不确定度分析的方法,为暖通空调专业应用不确定度分析提供参考。     

基于改进的TOPSIS的设备重要度分析

一个工业设备通常由多个子系统组成，各子系统在系统中的重要程度不同，导致了设计阶段的可靠性分配、运行阶段的检测水平以及维修方式的决策等都须以其重要度为基础。采用改进的TOPSIS确定系统中每个子系统的重要度，以满足实际需求。此方法在根据信息熵法求取各属性权重的基础上采用TOPSIS计算各子系统的重要度。将其应用到塑料挤出机的重要度分析中，结果表明，该方法对设备重要度的确定是有效的和实用的。     

基于结点重要度理论的运输枢纽布局方法研究

在公路运输枢纽总体规划中,枢纽的选址是重要的一环,也是决定区域公路运输系统的重要因素。结点重要度分析是为了定量描述区域内各结点间相对重要程度,从而为规划布局提供依据。将结点重要度理论引入公路运输枢纽布局,根据提出的相关指标应用结点重要度分析对枢纽布局备选点逐步筛选,最终确定最佳站址,从而指导运输枢纽的布局。所阐述的方法在部分公路运输枢纽总体规划中收到了良好的效果。     

基于FMECA法的电力机车用接触器故障重要度分析

接触器是电力机车内各类控制系统的重要组件。然而,多年来接触器故障率居高不下,严重影响电力机车的运行质量。本文面向接触器在电力机车运行现场的故障数据,根据FMECA（故障模式影响及危害性分析）法对接触器常发的12种故障模式的危害度和严重度进行分析,输出故障危害性矩阵,并结合危害性矩阵对各故障模式的重要度进行量化计算,根据重要度结果筛选关键故障模式,所得结论可为接触器的物料质量管理与提升提供依据。     

包含度及其在专家系统中的应用

在专家系统中有两类问题：一是检索问题，需要相似度的概念；一是推理问题，需要隐含度的概念。本文研究了包含度在专家系统中的应用，并指出它包括了证据理论及ＭＹＣＩＮ方法。     

Triple-Band Circularly Polarized Dielectric Resonator Antenna (DRA) for Wireless Applications

This paper proposes a new dielectric resonator antenna (DRA) design that can generate circularly polarized (CP) triple-band signals. A triple-band CP DRA antenna fed by a probe feed system is achieved with metal strips structure on side of DRA structure. The design start with conventional rectangular DRA with F shaped metal strips on DRA structure alongside the feed. Then, the F metal strip is enhanced by extending the length of the metal strip to obtain wider impedance bandwidth. Further improvement on the antenna performance is observed by improvised the conventional DRA structure. The method of removing part of DRA bottom resulted to higher antenna gain with triple band CP. The primary features of the proposed DRA include wide impedance matching bandwidth (BW) and broadband circular polarization (CP). The primary features of the proposed DRA include wide impedance matching bandwidth (BW) and broadband circular polarization (CP). The CP BW values recorded by the proposed antenna were ∼ 11.27% (3.3–3.65 GHz), 12.18% (4.17–4.69 GHz), and 1.74% (6.44–6.55 GHz) for impedance-matching BW values of 35.4% (3.3–4.69 GHz), 1.74% (5.36–5.44 GHz), and 1.85% (6.41–6.55 GHz) with peak gains of 6.8 dBic, 7.6 dBic, and 8.5 dBic, respectively, in the lower, central, and upper bands. The prototype of the proposed antenna geometry was fabricated and measured. A good agreement was noted between the simulated and the measured results.     

面向半导体制造业的统计过程分析与控制

传统的统计过程控制方法不能完全适应半导体制造业生产形式需要。本文在分析半导体光电封装制造模式的特点和实施过程控制所面临的问题的基础上,提出一种基于聚类分析的统计质量控制方法。通过实证分析,证实了该方法的可操作性并取得了良好的实际效果。     

位置敏感探测器定位分析和应用研究

位置敏感探测器是近几年问世的一种新型位置探测器,可直接用来测量角度、高度、距离及运动。本文论证了二维位置敏感探测器定位原理,导出了位置坐标的电流函数表达式,给出了相应的检测电路框图,提出了用位置敏感探测器进行人体三维运动测量的系统方案,并就信号的产生、提取及数据处理问题进行了讨论,最后估算了有关系统参数。     

多品种小批量生产的SPC应用研究

综述了多品种小批量生产方式的特点以及该生产方式下SPC(统计过程控制)的应用现状,指出常规控制图不适用于多品种小批量生产的问题,提出结合通用控制图、累积和(Cumulative-Sum,CUSUM)控制图和指数加权移动平均(Exponentially Weighted Moving-Averages,EWMA)控制图的解决方法,并总结出该SPC方法用于处理多品种小批量生产中微小偏差的步骤。     

激光诱导击穿光谱及其在元素分析中的应用

激光诱导击穿光谱是一种新的元素分析方法,但仍处于不断完善之中。利用它可以分析不同形态样品的成分,因此在成分分析和微量元素检测方面具有重要的应用前景。本文阐述了激光击穿诱导光谱仪的基本原理和激光诱导击穿光谱在多个领域中的应用,研究内容涉及固体样品、液体样品、气体样品、微量杂质分析和成分深度剖析等,并分析了基体效应、自吸收效应、测量时间、环境气体、激光参数等对激光诱导击穿光谱分析结果的影响。     

Additive Manufacturing of Porous Structures for Unmanned Aerial Vehicles Applications

Unmanned aerial vehicles (UAVs) have shown promising benefits in many applications. This has been enabled by the emergence of additive manufacturing (AM), which give the designers a large amount of geometrical freedom. In this paper, a novel design process of fused deposition modeling (FDM) combining both topology and infill optimization is introduced for AM of high performance porous structures. Tensile testing of FDM printed samples is first carried out to study the effect of the build orientation on the mechanical properties of acrylonitrile butadiene styrene (ABS) samples. It is found that samples built perpendicular to the load axis are the weakest with a tensile strength of 29 MPa and Young's modulus of 1960 MPa. The materials properties are fed to the finite elements analysis (FEA) for geometrical topology optimization, aiming to maximize stiffness and reduce weight of those parts. Afterwards, an infill optimization is carried out on the topology optimized parts using different mesostructures such as honeycomb, triangular, and rectangular to achieve high structural performance. The results showed that triangular pattern with 50% infill density had the lowest developed stresses, less mass, and strain energy when compared to other structures. Optimum UAVs parts of a quadcopter are successfully manufactured, assembled, and tested.

     

锡酸盐与Mg(OH)2复合阻燃剂对软PVC的阻燃消烟作用

用极限氧指数(LOI)、烟密度和剩炭率研究了锡酸盐和Mg(OH)2复合阻燃剂对软PVC的阻燃消烟作用。用热分析方法研究了阻燃软PVC从室温到800℃的降解过程,结合对材料燃烧后剩炭结构的观察对阻燃机理进行了初步的探讨。结果表明:锡酸盐和Mg(OH)2复合使用能明显提高对软PVC的阻燃效率,Mg(OH)2主要通过脱水吸热作用使材料的阻燃性能提高,而锡酸盐可分别在凝聚相和气相起作用,但主要为凝聚相Lewis酸催化机理。     

Flexible and Tough Poly(lactic acid) Films for Packaging Applications: Property and Processability Improvement by Effective Reactive Blending

This study demonstrates a practical means to overcome inherent brittleness problem of poly(lactic acid) (PLA) and make PLA feasible as packaging material. PLA with suitable processability is utterly required for package manufacturers, where flexible, tough PLA film is essential for packers and end users. Highly flexible PLA films with 60‐fold increase in elongation at break (Eb) over that of the neat PLA were successfully produced by integrating effective reactive blending and economical film blowing process. The ‘two‐step’ blending was used to prepare PLA compound; poly(butylene adipate‐co‐terephthalate) (PBAT – another biodegradable polymer) was first blended with 0.5–1% chain extender (epoxy‐functionalized styrene acrylic copolymer) (ESA), followed by subsequent blending with PLA in twin‐screw extruder. Blown films of reactive blend of PLA/PBAT/ESA (80/20/1) showed impressively high Eb of 250% versus a very low Eb of 4% for the neat PLA. Resulting blown films still possessed high modulus of 2 GPa, yield stress of 50–60 MPa and good toughness of ~100 MPa. Significant enhancement in the film's ductility was attributed to homogeneous blend with developed fine strand‐like structure as a result of effective in situ compatibilization and good interfacial adhesion between the PLA and PBAT. PLA/PBAT/ESA blend also offered improved processability. Resulting films had acceptable haze of ~10% for common packaging, and clearer film close to PLA (≤2%) could be obtained by designing PLA skin layers in multilayer structure. Films of PLA/PBAT/1%ESA exhibit potential as packaging material; their mechanical and optical properties are comparable with or even exceed some existing films used in the market. Copyright © 2015 John Wiley & Sons, Ltd.     

Condition-based fault tree analysis (CBFTA): A new method for improved fault tree analysis (FTA), reliability and safety calculations

Condition-based maintenance methods have changed systems reliability in general and individual systems in particular. Yet, this change does not affect system reliability analysis. System fault tree analysis (FTA) is performed during the design phase. It uses components failure rates derived from available sources as handbooks, etc. Condition-based fault tree analysis (CBFTA) starts with the known FTA. Condition monitoring (CM) methods applied to systems (e.g. vibration analysis, oil analysis, electric current analysis, bearing CM, electric motor CM, and so forth) are used to determine updated failure rate values of sensitive components. The CBFTA method accepts updated failure rates and applies them to the FTA. The CBFTA recalculates periodically the top event (TE) failure rate (λ_TE) thus determining the probability of system failure and the probability of successful system operation—i.e. the system's reliability.FTA is a tool for enhancing system reliability during the design stages. But, it has disadvantages, mainly it does not relate to a specific system undergoing maintenance.CBFTA is tool for updating reliability values of a specific system and for calculating the residual life according to the system's monitored conditions. Using CBFTA, the original FTA is ameliorated to a practical tool for use during the system's field life phase, not just during system design phase.This paper describes the CBFTA method and its advantages are demonstrated by an example.     

压电聚偏氟乙烯纳米纤维的应用进展

压电聚合物因柔性、加工容易和成本低等优点备受人们的关注,尤其是在生物医学、能源和电子信息等领域的数据储存器、纳米发电机、传感器和驱动器等器件的开发方面有十分广泛的应用。文中对聚偏氟乙烯的结晶结构、晶型调控以及应用方面进行综述,重点介绍聚偏氟乙烯压电聚合物纳米纤维材料的结构调控及在纳米器件等应用方面的最新研究进展。