基于GO法的装配式建筑工程风险评价

装配式建筑的大力推广及应用,对装配式建筑工程风险管理工作提出了新的挑战。本文在分析GO法基本原理的基础上,从整个预制构配件生产、物流运输至现场装配施工的多个维度为切入点,在建造系统流程图的基础上建立了装配式建筑工程GO图模型,应用GO运算规则计算系统的风险状态概率值,参照风险等级划分标准实现对系统的风险评价,以期为装配式建筑工程相关风险研究提供新思路。     

基于常见液压传动系统的设计思路

液压传动系统设计是整个机械设备设计的重要组成部分,文章基于经验设计法介绍了常见液压传动系统的设计思路,即明确液压系统的设计要求;进行现场工况分析,确定系统的主要参数;确定液压系统方案,编制液压系统原理图;计算参数和选择液压元件;验证液压系统的性能;绘制工作图纸,编制工艺技术文件。     

基于整体性的制造企业供应链可靠性分析

制造企业要获得高的市场反应能力和效益,必须要有高的供应链系统可靠性做保障。针对制造企业供应链系统,结合GO法,建立出基于威布尔分布的制造企业供应链系统GO模型。运用定量分析法,研究系统的整体可靠度函数与失效率函数的表达式和图形,通过实例对表达式和图形进一步证明。结果表明:通过将GO法运用于制造企业的供应链系统可以清晰、直观地表达出供应链系统的可靠度及失效率的变化情况,并从表达式和图形中可以追溯出影响制造企业供应链系统整体可靠性的关键因素,为制造业供应链系统制定出相关可靠性管理措施提供科学的依据。     

一种带冷却功能的采棉机液压油箱介绍

采棉机因其高度的机械化和自动化水平在新疆得到了较好的应用与推广。对于采棉机而言,液压系统如同其血液系统,采棉机液压油箱是液压系统中重要的组成部分,文章通过对采棉机液压油箱结构的介绍,指出了传统液压油箱存在的问题,进而给出一些改进方案,并取得了积极效果。     

浅谈矿山机械液压系统常见故障及故障分析

矿山机械在使用过程中,受各种因素的影响,其液压系统容易发生故障。由于液压系统封闭运行,进一步增加了故障检测和判断的难度。为了确保矿山机械正常运行,需要研究分析其存在的故障。为此,本文通过对矿山机械液压系统的常见故障进行研究分析,提出相应的检测方式,为分析液压系统的故障提供参考依据。     

自动仓储系统市场与应用

主持人语:广义来讲,自动仓储系统是指对集装单元货物进行自动装卸车、自动堆拆码、自动存取并实现自动控制和信息管理的仓储系统。自动仓储系统的种类很多,其主流模式为有轨巷道堆垛机高架自动仓储系统(AS／RS),也称为自动化立体库。可以说,自动仓储系统几乎涵盖了物流技术与设备的方方面面,是高端、先进的物流技术的集中体现。     

浅析液压系统

液压系统是机械工程中一项应用最广泛的技术,本文从对液压系统的理解出发,对其进行的系统描述,同时联系相关的液压理论,综合阐述了作者对液压系统的认识。     

一种带冷却功能的采棉机液压油箱介绍

采棉机因其高度的机械化和自动化水平在新疆得到了较好的应用与推广。对于采棉机而言，液压系统如同其血液系统，采棉机液压油箱是液压系统中重要的组成部分，文章通过对采棉机液压油箱结构的介绍，指出了传统液压油箱存在的问题，进而给出一些改进方案，并取得了积极效果。     

浅析液压系统

液压系统是机械工程中一项应用最广泛的技术,本文从对液压系统的理解出发,对其进行的系统描述,同时联系相关的液压理论,综合阐述了作者对液压系统的认识.     

平地机、挖掘机液压系统的保养与维护

平地机、挖掘机是最为常见的工程机械之一,作为其主要工作部件,液压系统直接影响着其行走、挖掘、回转等功能的实现,如何保养和维护平地机、挖掘机液压系统,关系着其正常使用。本文通过分析平地机、挖掘机液压系统的组成,根据实际应用经验,详细介绍了平地机、挖掘机液压系统的维护与保养。     

On the reliability of unitizing textual continua: Further developments

This paper builds on an agreement coefficient proposed by Krippendorff (Content analysis: an introduction to its methodology, 2013) for measuring the reliability of unitizing and coding continuous phenomena, for example, of texts, videos, or sound recordings. It serves three purposes: It modifies Krippendorff’s definition which turned out to behave not as expected when applied to more than two observers, coders, or annotators. It extends this reliability measure to a family of four coefficients able to assess the reliabilities of diverse properties of unitized continua. It adds a way to obtain the confidence intervals of these coefficients as well as the probability of failing to reach targeted reliability levels. And it describes and provides access to free software that calculates all values of this family of reliability coefficients.     

Confidence intervals for maximal reliability in tau‐equivalent models

Subjective probabilities play an important role in marketing research, for example where individuals rate the likelihood that they will purchase a new developed product. The tau‐equivalent model can describe the joint behaviour of multiple test items measuring the same subjective probability. In this paper we stress the use of confidence intervals to assess reliability, as this allows for a more critical assessment of the items as measurement instruments. To improve the reliability one can use a weighted sum as the outcome of the test rather than an unweighted sum. In principle, the weights may be chosen so as to obtain maximal reliability. We propose two new confidence intervals for the maximal reliability in the tau‐equivalent model and we compare these two new intervals with intervals derived earlier in Yuan and Bentler (Psychometrika, 67 , 2002, 251) and Raykov and Penev (Multivariate Behavioral Research, 41 , 2006, 15). The comparison involves coverage curves, a methodology that is new in the field of reliability. The existing Yuan–Bentler and Raykov–Penev intervals are shown to overestimate the maximal reliability, whereas one of our proposed intervals, the stable interval, performs very well. This stable interval hardly shows any bias, and has a coverage for the true value which is approximately equal to the confidence level.     

Factors affecting intercoder reliability: a Monte Carlo experiment

Although it has long been a consensus that intercoder reliability is crucial to the validity of a content analysis study, the choice among them has been debated. This study reviewed and empirically tested most popular intercoder reliability indices, aiming to find the most robust index against prevalence and rater bias, by empirically testing their relationships with response surface methodology through a Monte Carlo experiment. It was found that Maxwell’s R.E is superior to Krippendorff’s α, Scott’s π, Cohen’s κ, I _r of Perreault and Leigh, and Gwet’s AC ₁. More nuanced relationships among prevalence, sensitivity, specificity and the intercoder reliability indices were discovered through response surface plots. Both theoretical and practical implications were also discussed in the end.     

Simulation of alternative regulations in the Colombian electricity market

The deregulation of the Colombian electricity system took place in 1994 and the pool started operations in 1995. The Colombian system adopted a capacity charge mechanism to increase incentives to invest in new capacity. The capacity charge was showing strength, and apparently driving investments during the initial years. However, the mechanism started to exhibit weaknesses in terms of transparency and disincentives, causing a negative effect on investments. Different authors have presented alternative regulatory options to update the system. A non-standard system dynamics approach to evaluate alternative regulation schemes for the Colombian electricity market is proposed. A specific regulation problem is undertaken to illustrate the proposed methodology. It shows how the capacity charge mechanism, which has been used for reliability purposes, might be changed for alternative schemes. The proposed transformations to the actual regime seem to overcome some of its drawbacks. Simulation results indicate these alternatives improve the general system behaviour. In addition, the underlying model has been used afterwards for other energy policy purposes.     

Applying structural equation modeling methodology to test validation: an example of cyberspace positive psychology scale

Although the structural equation modeling (SEM) methodology is a powerful tool for validating psychological measurements, few studies have used complete SEM-based indexes in test validation. This study developed and validated the cyberspace positive psychology scale (C-PPS) via SEM techniques. A total of 411 college students were recruited from four universities in Taiwan for the study. Hierarchical confirmatory factor analysis was used to test construct validity, and a structural model provided criterion-related validity. Reliability was reported via composite reliability. Results of the analyses show that the C-PPS demonstrated high reliability and good construct validity. Furthermore, criterion-related validity identified that although positive psychology in cyberspace and positive psychology in real life contexts are correlated, the two are also distinguishable. To conclude, the C-PPS is valid and reliable. The validation of the C-PPS indicates that college students can exhibit positive psychological traits in both the real and virtual worlds.     

Remaining life estimation of used components in consumer products: Life cycle data analysis by Weibull and artificial neural networks

Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. To competitively exploit these products, one option is to incorporate used components in “new” or remanufactured products. However, this option is partly limited by a firm's ability to assess the reliability of used components. A comprehensive two-step approach is proposed. The first stage phase statistically analyzes the behavior of components for reuse. A well-known reliability assessment method, the Weibull analysis, is applied to the time-to-failure data to assess the mean life of components. In the second phase, the degradation and condition monitoring data are analyzed by developing an artificial neural network (ANN) model. The advantages of this approach over traditional approaches employing multiple regression analysis are highlighted with empirical data from a consumer product. Finally, the Weibull analysis and the ANN model are then integrated to assess the remaining useful life of components for reuse. This is a critical advance in sustainable management of supply chains since it allows for a better understanding of not only service requirements of product, but the remaining life in a product and hence its suitability for reuse or remanufacture. Future work should assess: (1) reduction in downtime of process equipment through the implementation of this technique as a means to better manage preventative maintenance; (2) reduce field failure of remanufactured product; (3) selling-service strategy through implementation of the proposed methodology.     

WSR方法论在房地产企业管理中的应用

WSR即物理—事理—人理方法论,是我国学者将东方人文哲学融入西方系统工程方法论的成果。将WSR方法论应用于房地产开发企业管理,就是在充分理解物理—事理—人理的基础上分解房地产开发企业的管理活动,按照WSR方法论分解和实施房地产开发企业管理活动,有利于将其结构化,规范化,提高企业管理效率。     

现代城市及其管理——一类开放的复杂巨系统

开放的复杂巨系统及其方法论对现代城市管理具有重要的指导意义.城市管理者应超越还原论局限,抓住信息技术引领的管理变革机遇,以信息化城市管理系统建设为契机,抓好专家体系、计算机体系、数据信息体系的综合集成,大力加强城市综合管理与协调、高度重视城市管理中人的因素、以复杂巨系统及其方法论指导城市管理工作.在对现代城市及城市管理的复杂性分析基础上,论文论述了综合集成法在城市管理中的应用,构建了城市管理的综合集成体系结构和流程图.     

浅析汽车产品可靠性工程及其构建

汽车可靠性工程学是把可靠性工程学的最基本的方法和原理结合汽车工程的问题,形成以研究汽车可靠性设计、分配、预测、试验、评价、维修性等为主要内容的应用型科学。本文阐述了汽车产品可靠性工程内容及设计构建的方案。