A reliability evaluation method based on the weakest failure modes for side-by-side offloading mooring system of FPSO

Offshore structures are complex systems, and numerous failure modes must be taken into consideration when reliability analysis in different loads and environment conditions are conducted on them. It is difficult to obtain structural system reliability with respect to complicated systems with numerous failure modes and dependency consideration among them. This paper applies the combination of the weakest failure modes theory with structural reliability theory to conduct reliability analysis on of side-by-side offloading mooring system of FPSO. Firstly, the numerical simulation of the system in different conditions is addressed to acquire the statistical data of time-history stress of components including hawsers, fenders and yoke, based on which, the reliability indexes of all the failure modes and correlation coefficient matrix are derived. Then the weakest failure modes, i.e. the representative failure modes that have significant impact on the system, are located through Probability Network Evaluation Technique. The probability of structural system is estimated through the weakest failure modes by considering the system as series. The analysis results indicate that two environment conditions (0°&0°&0° and 0°&30°&45° in combinations of wave, wind and current) are relative dangerous, which is in good correspondence with the practical expertise. The method is verified to be an effective and convenient evaluation approach for structural reliability analysis in terms of complex systems. It is beneficial for the identification of structure indicators from the weakest failure mode group and conduct optimum of structural system configurations in the design stage.     

Working in small family businesses: empirical comparisons to non-family businesses

Members of the owning family of a small family firm are reputed to experience special problems, most notably specific types of conflicts and outcomes associated with them. This analysis uncovered more advantages than disadvantages, however, when family members were compared to non-family members of the same firms and to members of similar non-family-owned businesses. Previous literature had not used comparison groups and may have been based upon a subset of family businesses that differs systematically from family firms in general and from this study's sample specifically. © 1997 John Wiley & Sons, Ltd.     

孔隙结构对焦碳燃烧影响的数值研究

煤粒在热解过程中,由于不同的加热速度和不同的热解最终温度所产生的孔隙结构也不同,本文建立了多组分并存的情况下,综合考虑化学反应,内外传递过程及颗粒孔结构变化在内的单颗粒焦碳着火燃烧模型,计算出３种不同孔隙结构焦碳的转化率,氧化反应率及比面积的变化,比较了它们之间的差异。     

施工组织非正式网络结构特征与组织安全行为的关系研究

为了提升建筑施工安全管理水平,从社会网络的视角分析了施工组织非正式网络的结构特征对组织安全行为的影响关系,构建了施工组织非正式网络结构特征、安全沟通和组织安全行为的理论模型,实证分析了91个施工组织非正式网络的结构特征,使用多层回归分析的方法验证了上述模型。结果表明:网络密度对组织安全行为有显著正向影响,安全沟通在密度与组织安全行为的关系中起到了部分中介作用;出度中心势对组织安全行为有显著正向影响,安全沟通起到了完全中介作用;入度中心势对组织安全行为没有显著影响,安全沟通没有起到中介作用;中间中心势对组织安全行为没有显著影响,安全沟通没有起到中介作用;平均路径长度对组织安全行为有显著负向影响,安全沟通起到了完全中介作用;聚类系数对组织安全行为有显著正向影响,安全沟通起到了完全中介作用。     

动态惩罚机制下企业安全生产行为演化分析

为揭示动态惩罚机制下企业安全生产行为规律,以企业成本和收益为基础,通过区域内所有企业的博弈,运用演化博弈理论研究不同策略下企业对安全生产投入达标行为演化趋势.研究结果表明:当政府监管能力有约束时,无论企业是否明确预设控制目标,均可能出现投机心理,而政府加大惩罚力度可有效改善整体安全生产水平;同时,企业明确控制目标时,通...     

The effects of parental altruism on the governance of family‐managed firms

We draw on the economic, corporate governance, and family business literatures to explain why the effects of family on family firms makes this governance form theoretically distinct from those of public and private non‐family firms. Our thesis is that parental altruism, when combined with private ownership and owner‐management, influences the ability of the firm's owner‐manager to exercise self‐control, which, in turn, can expose some family firms to conflicts rooted in the agency threats of moral hazard, hold‐up, and adverse selection. We then discuss why some other family firms are able to minimize these dark side threats and thereby attain altruism's brighter side. Finally, we discuss how altruism's influence changes over time as ownership becomes dispersed among family members and across generations. Copyright © 2005 John Wiley & Sons, Ltd.     

分层抽样法在实验室废液量统计中的应用

实验室废液由于受实验室性质和科研课题数量的影响,其排放源分散,废液排放周期不定,排放水量也无规律性;因此要对一个城市和一定区域实验室的废液排放量进行准确统计监管非常困难.本文采用分层抽样中的比率估计法SRE对某城市实验室废液进行了统计.统计结果显示,该城市科研实验室废液排放总量为107.8 T,统计误差为10.04 T.实验室间的差异以及调查统计的准确性是造成误差的主要原因.该方法用于实验室废液的统计能够反映实际的废液排放情况,适合于环保管理部门用来对实验室废液进行监管.     

组织定向的人因失误因果模型及影响关系研究

为了更好地从源头上预防人因失误,首先,基于系统理论发展一个组织定向人因失误的"结构-行为"因果模型,包括组织子模型、情境状态子模型、个体因素子模型以及人因失误子模型。然后,分析模型中各子模型之间以及其因素类别之间的直接和间接影响关系,如模型中各层级之间的因果关系:组织因素→情境状态因素→直接触发人因失误的个体因素→人的认知行为失误。最后,基于事件报告分析、专家意见和文献资料,并依据建立的4种影响类型(I,C,A,N)识别具体情境环境与人因失误或认知行为之间的影响关系。分析结果表明,情境环境因素对人因失误的影响非常复杂,不同的情境环境因素对同一人因失误可能产生不同类型的影响,同一情境环境因素对不同的人因失误可能产生不同类型的影响。     

On the gasification of biomass: Data analysis and regressions

The use of solid wastes as a way to produce energy and chemicals is one of the frontiers in chemistry. One of these methods is the biomass gasification. In this thermal treatment the biomass is heated in a partially oxidising environment using different process conditions.The variability of both biomass composition and process conditions can lead the thermal treatment to several different results. In order to find a methodology for the classification of all the involved data a dataset containing biomass characterization, gasification process conditions and obtained syngas properties have been gathered from the literature.This dataset has been analysed through multivariate analysis. Principal component analysis (PCA) and a partial least square analysis (PLS) have been performed. Several correlations among different biomass and their gasification products have been found among input parameters, such as biomass properties and process conditions, and output variables like products composition and properties.     

异质森林火灾模型及火灾扑救对森林生态系统的影响

森林火灾元胞自动机模型是研究自组织临界性的经典模型之一。这一模型中森林用一个二维网格来表示,其中每个格点代表一棵树或代表空地,各节点的树具有相同的生长概率和着火概率,以一定的规则进行演化。这一模型没有考虑树木间的差别,因而是同质的。我们考虑到不同树木间由种类、树龄等原因引起的生长概率与着火概率的不同,改进了经典森林火灾模型,提出了一个异质森林火灾模型,并研究了这一模型的自组织临界性。在新模型的基础上,研究了火灾扑救对森林群落分布的影响,给出了模拟结果,该结果与实际的观测结果得到符合。该文的研究可望对森林火灾预测及研究火灾扑救对森林生态系统的影响具有一定的意义。     

Organisational learning and continuous improvement of health and safety in certified manufacturers

Certified management systems have increasingly been applied by firms in recent decades and now cover the management of health and safety, principally through the OHSAS 18001 standard. In order to become certified, firms must not only observe the relevant legislation, but also improve performance and raise goals within health and safety on a continuous basis. The article examines how certified occupational and health management systems influence this process to evaluate how far they hinder or support learning. It presents a model with which it is possible to identify and analyse improvement processes. The model is applied to five cases from a qualitative study of Danish manufacturers with certified health and safety management systems. The cases illustrate the wide variation in health and safety management among certified firms.Certification is found to support lower levels of continuous improvement performance in handling health and safety issues. However, more advanced improvement practices are shown to be connected to the integration of health and safety in other managerial areas, as well as to the employment of similar advanced improvement processes within firms. The article argues that certified health and safety management does not obstruct learning, and can support advanced learning. Improvement practices with regard to health and safety are mainly dependent upon the firm’s overall organisational processes and do not automatically arise from the standard alone.     

Role of gender in road accidents

Influence of driver sex on road accidents is assessed in this article. Accident records for 3 years and for three different income regions were analyzed. Annual distance traveled, social and economic participation, and effect of public vehicle accidents were considered. Effects of environmental factors and driver age were also included. Driver faults analysis identified possible reasons for accident differences. Analysis of accident severity was used to assess degree of harm. Statistical analysis at the 5% significance level was used to evaluate all differences. The results show that male accident rates are significantly higher. This trend is consistent through all the analyses. Accident differences are significant only in normal driving conditions. Drivers over age 50 had the lowest accident rates. Accident rate differences were caused by lack of attention and impatience among male drivers. Appropriate means of communication should alert concerned populations to these findings.     

基于贝叶斯网络的消防协同治理影响因素研究

为有效提升消防安全协同治理的效能,在识别和量化政府部门、企业和公民社会消防协同治理的影响因素的基础上,分别构建政府部门、企业和公民社会影响因素的贝叶斯网络模型,辨识影响实现高效消防协同治理的关键因素.研究结果表明:部门的权力与利益、有效领导和组织激励3个因素对政府消防协同治理影响最为显著;交流沟通和参与渠道分别是影响企...     

Luminance of the Surround and Visual Fatigue of VDT Operators

Luminance distribution in the visual field is considered as one of causal factors with a significant influence on visual fatigue, especially for intensive and extended Video Display Terminal (VDT) work. The aim of the study was to define visual fatigue of VDT operators for different values of surrounding luminance. Experiments were carried out in laboratory conditions under 3 lighting conditions. Only 1 lighting parameter—the luminance of the wall behind the display (surrounding luminance)—changed. Visual fatigue was measured both by a subjective evaluation of different visual complaints (asthenopic symptoms) and by objective measurements of changes in the following visual functions: accommodation, convergence, habitual horizontal phoria, critical fusional frequency (CFF), and visual acuity. The same experiments were done for CRT (Cathode Ray Tube) and LCD TFT (Liquid Crystal Display with Thin Film Transistor) screens. The results of the study have shown that there was no significant influence of the value of surrounding luminance on the asthenopic symptoms for either type of screen. A general tendency towards bigger visual complaints for LCD TFT than for CRT participants was found. An objective evaluation of visual fatigue demonstrated a tendency towards bigger changes in visual functions with an increase of surrounding luminance for both screens. Statistical analysis of the results has shown that surrounding luminance influences significantly the reduction of the accommodation amplitude (significance level < .05).     

What’s past is prologue: Organizational learning from a serious patient injury

This exploratory case study examines how one hospital learned from an adverse event (AE), a medication overdose that seriously injured a patient. Using qualitative data analysis, we examined how four professional groups reacted to the AE: physicians, nurses, pharmacists, and representatives from the combined quality assurance and risk management departments. Following the AE, each professional group classified the event differently, assessed a different segment of history, made decisions about different issues, and chose different courses of action. Despite these differences, the physician, nursing and pharmacy management teams all decided on which solutions to implement before the first root cause analysis meeting was convened. Indeed, to understand how the hospital implemented changes in the aftermath of the AE, it was necessary to examine the learning from near misses and other warnings that preceded it. This case highlights the importance of the politics of organizational learning and raises theoretical and practical questions about how hospitals learn from potential and actual adverse events.     

环境监测全过程质量管理分析

在我国环保事业发展中,环境监测工作发挥着非常重要的作用,它为环保部门的决策提供参数依据,也为区域内环境状态提供科学参考,同时,还可以帮助区域环保监督部门进行污染源分析。本文就环境监测工作的特点进行了分析,并探讨了环境监测质量管理工作中的主要问题,提出了优化环境监测水平及其质量的重要措施。     

Occupational injury rates among Norwegian farmers: A sociotechnical perspective

Introduction: This study addressed relative injury risk among Norwegian farmers, who are mostly self-employed and run small farm enterprises. The aim was to explore the relative importance of individual, enterprise, and work environment risks for occupational injury and to discuss the latent conditions for injuries using sociotechnical system theory. Method: Injury report and risk factors were collected through a survey among Norwegian farm owners in November 2012. The response rate was 40% (n = 2,967). Annual work hours were used to calculate injury rates within groups. Poisson regression using the log of hours worked as the offset variable allowed for the modeling of adjusted rate ratios for variables predictive of injury risk. Finally, safety climate measures were introduced to assess potential moderating effects on risk. Results: Results showed that the most important risk factors for injuries were the design of the workplace, type of production, and off-farm work hours. The main results remained unchanged when adding safety climate measures, but the measures moderated the injury risk for categories of predominant production and increased the risk for farmers working with family members and/or employees. An overall finding is how the risk factors were interrelated. Conclusions: The study identified large structural diversities within and between groups of farmers. The study drew attention to operating conditions rather than individual characteristics. The farmer’s role (managerial responsibility) versus regulation and safety climate is important for discussions of injury risk. Practical Applications: We need to study sub-groups to understand how regulation and structural changes affect work conditions and management within different work systems, conditioned by production. It is important to encourage actors in the political-economic system to become involved in issues that were found to affect the safety of farmers.     

Exploring patterns of multiple climates and their effects on safety performance at the department level

Introduction: This paper represents a first attempt to fill a gap in research about different specific climates and safety outcomes, by empirically identifying patterns of climates and exploring the possible effect of different climates at the department level on some specific safety outcomes. The first objective was to explore how different specific climates (safety, communication, diversity and inclusion) can be associated to each other, considering the department level of analysis. The second objective was to examine the relationships between those patterns of climates with safety performance (compliance and participation behaviors). Method: A total of 429 blue-collar workers in 35 departments answered a questionnaire covering safety, diversity, inclusion, and communication climate measures. Cluster analysis was performed to identify clusters of departments with different climate patterns and their impact on safety compliance and safety participation behaviors. Subsequently, a hierarchical multiple linear regression was conducted at the individual-level to test the effect of climate patterns, by controlling for some sociodemographic variables. Results: Results showed the existence of four differentiated clusters of departments. Three of those clusters showed homogenous patterns (coherent association among perceptions of low, medium and high climates) and one heterogeneous (low and medium perceptions). The findings also revealed that the higher the climates perceptions, the higher the levels of safety participation and safety compliance, with safety participation being more affected than compliance. Conclusions: The present research showed the associated effects of some organizational climate factors, such as fair treatment, inclusion, safety and communication within the organization, which had not been previously studied in their combined relationships, on safety behaviors. Practical applications: Several other organizational climate factors, such as fair treatment, inclusiveness and communication, may play an important role in safety, showing the importance of broadening the focus on safety climate as one of the main predictors of safety behaviors.     

Occupational Health and Safety From Communist to Capitalist Structures

This article focuses on individual effects of the transformation from communist to capitalist structures in the system of occupational health and safety (OHS). Despite basic similarities among the communist nations the systems of OHS differed immensely. The political changes during transformation additionally contributed to varying opportunities for the development of OHS systems. Changes affecting the living and working conditions are significant and are demonstrated by the development of new work structures and work biographies. This is reflected in changed attitudes to demands and contents of work. No differences, however, were found between the employed and unemployed when asked about these issues. Conclusions for OHS in postcommunist states are drawn.     

Comparing the work values of engineers with managers,production, and clerical workers: A multivariate analysis

Engineers and scientists have been compared in previous research on their work attitudes. Conceivably the interest in comparing these two groups of professionals was a result of the joint work they often do in research and development departments. The present framework suggests that engineers who work in production departments would have work values and attitudes which would be more similar to those of managers. Survey data was collected from 432 employees in two industrial corporations in Israel. Profile analysis showed that the work values of engineers were similar to those of managers and different from those of production and clerical workers. Furthermore, work values were also related to behavioral outcomes such as performance and tardiness. Implications regarding the study of engineering as a profession and the use of work values in organizational research are discussed.