EOQ model for imperfective items under a one-time-only discount

In practice, when a supplier is confronted with extreme completion in markets, unanticipated surplus in inventory, or change in the production run of a product, he/she may offer a special price discount to motivate buyers to order a special quantity. The purpose of the present paper is to investigate an inventory model for imperfective items under a one-time-only discount, where the defectives can be screened out by a 100% screening process and then can be sold in a single batch by the end of the 100% screening process. The optimal order policies associated with three kinds of effective times of the reduced price are obtained. Finally, a numerical example is provided to illustrate the proposed model.     

Self-perceived occupational stress and distress in a Scottish police force

Abstract

This paper describes an empirical study (n = 699) of occupational stress in a Scottish police force. The self-perceived stress associated with a variety of organizational and opearational stressors was examined along with the associated distress in the police officers in terms of symptoms of anxiety, somatic complaint, severe depression and social dysfunction. The analysis revealed that in spite of the potential that police work offers for exposure to adverse opeational situations such as violence or death, the highest levels of associated stress lie in relation to organizational factors such as officers' perceptions of staff shortages, inadequate resources, time pressures, lack of communication and work overload. Differential rates of perceived stress are reported accordng to gender, rank and working location. This paper further validates previsous research on stress in British police and addresses the situation from a Scottish perspective.     

The shape of protective capacity in unbalanced production systems with unplanned machine downtime

Several studies have shown that when both statistical fluctuations and dependent events exist, unbalanced production lines out-perform balanced lines. By definition, unbalanced lines have some amount of protective capacity built into them; however, little research exists to address the question of quantity and position of protective capacity necessary to counteract the impact of variation on system performance. This research seeks to improve our understanding concerning the shape of protective capacity in unbalanced lines when faced with variation in the form of unplanned machine downtime. Both Kanban and drum-buffer-rope (DBR) controlled lines are investigated. Results show that balancing the protective capacity yields superior results over both increasing and decreasing protective capacity shapes (holding average protective capacity equal). Results also show that Kanban lines behave differently than DBR lines.     

The role of stress and social support in Sick Building Syndrome

Sick Building Syndrome (SBS) involves seemingly healthy individuals experiencing long-lasting symptoms of physical distress in their work settings and is estimated to exist in 20 to 30% of all work settings in the USA. We examined differences in stress, social support and both physical and psychological symptoms reported by hospital personnel working in known SBS sites in Halifax, Nova Scotia (n = 297) with control employees working in relatively SBS-free settings (n = 228). We found that employees reporting that their health had been affected by the building in which they worked and those complaining of poor air quality were more likely to be found in SBS locations. In addition, those people with higher levels of organizational support and marginally higher levels of union support were also more likely to be found in SBS locations. Further analyses revealed that employees with higher role overload and greater family support, but lower levels of organizational support were more likely to report that their own health had been adversely affected by their place of work. Perceptions of poor air quality were predicted by higher levels of role conflict, role overload, and organizational stress and lower levels of organizational support. These results suggest that SBS may not be solely dependent on environmental factors.     

Conflict of Interest Mitigation Procedures May Have Little Influence on the Perceived Procedural Fairness of Risk‐Related Research

Two between‐subject experiments explored perceived conflict of interest (COI)—operationalized as perceived procedural unfairness—in a hypothetical public–private research partnership to study the health risks of trans fats. Perceived fairness was measured as subjects’ perceptions that health researchers would be willing to listen to a range of voices and minimize bias (i.e., COI) in the context of a research project. Experiment 1 (n = 1,263) randomly assigned research subjects to a partnership that included (1) a combination of an industry partner, a university partner, and a nongovernmental organization (NGO) partner; and (2) one of three processes aimed at mitigating the potential for COI to harm the quality of the research. The procedures included an arm's‐length process meant to keep the university‐based research team from being influenced by the other partners, an independent advisory board to oversee the project, and a commitment to making all data and analyses openly available. The results suggest that having an industry partner has substantial negative effects on perceived fairness and that the benefit of employing a single COI‐mitigation process may be relatively small. Experiment 2 (n = 1,076) assessed a partnership of (1) a university and either an NGO or industry partner and (b) zero, one, two, or three of the three COI‐mitigation procedures. Results suggest there is little value in combining COI‐mitigation procedures. The study has implications for those who aim to foster confidence in scientific findings for which the underlying research may benefit from industry funding.     

A Case Study Evaluating the Risk of Infection from Middle Eastern Respiratory Syndrome Coronavirus (MERS‐CoV) in a Hospital Setting Through Bioaerosols

Middle Eastern respiratory syndrome, an emerging viral infection with a global case fatality rate of 35.5%, caused major outbreaks first in 2012 and 2015, though new cases are continuously reported around the world. Transmission is believed to mainly occur in healthcare settings through aerosolized particles. This study uses Quantitative Microbial Risk Assessment to develop a generalizable model that can assist with interpreting reported outbreak data or predict risk of infection with or without the recommended strategies. The exposure scenario includes a single index patient emitting virus‐containing aerosols into the air by coughing, leading to short‐ and long‐range airborne exposures for other patients in the same room, nurses, healthcare workers, and family visitors. Aerosol transport modeling was coupled with Monte Carlo simulation to evaluate the risk of MERS illness for the exposed population. Results from a typical scenario show the daily mean risk of infection to be the highest for the nurses and healthcare workers (8.49 × 10^?4 and 7.91 × 10^?4, respectively), and the lowest for family visitors and patients staying in the same room (3.12 × 10^?4 and 1.29 × 10^?4, respectively). Sensitivity analysis indicates that more than 90% of the uncertainty in the risk characterization is due to the viral concentration in saliva. Assessment of risk interventions showed that respiratory masks were found to have a greater effect in reducing the risks for all the groups evaluated (>90% risk reduction), while increasing the air exchange was effective for the other patients in the same room only (up to 58% risk reduction).     

创始爱心资金获取：情感信任还是能力信任

创始资金是新创企业开展创业活动的关键资源,但由于新创弱性和缺乏有效的市场记录,创业者不得不更多寻求非正式制度的社会网络支持,来自家人和朋友的爱心资金是对正式金融机构融资制度的重要补充和替代。已有研究大多将爱心资金与爱和情感联系起来,忽视理性因素的考虑。结合中国的制度文化情景,建立基于情感信任和理性信任的爱心资金获取整合模型,深化创业资金获取的社会网络和制度理论分析。基于2009年至2011年中国新生创业活动动态跟踪调研数据进行实证分析,采用Probit回归方法对社会网络、制度环境、创业活跃度和爱心资金之间关系进行理论分析和实证检验,进一步考察爱心资金结构差异对创业绩效的影响。研究结果表明,情感信任与能力信任的交互作用与爱心资金存在正相关关系,制度环境对情感信任与能力信任的交互作用与爱心资金的关系存在负向调节,创业活跃度则呈现正向调节。研究结论拓展和深化了创业社会网络的分析框架,将情感和理性因素结合起来,突破了已有研究对于血缘的利他主义和朋友的道义责任的情感性单一解释。     

The Information Environment of War

This article observes high levels of anxiety about war in the present era, although wars are in decline. It addresses this paradox by distinguishing ideal‐typical features of Industrial and Information War. Industrial War is fought predominantly between states over territory, harnesses industry and the military, and requires mass mobilisation of people as well as resources. Information War is the prerogative of a few advanced societies and has emerged in a context that has enabled the extension of market practices on a global scale (with America as a unipolar power). Information War transcends frontiers, is asymmetrical, and its hard side is manifest in digitalised technologies and small professional forces. However, its soft side evokes the expanded and fast‐changing information environment of globalised media, trans‐national networks and the Internet. Through these, media wars can be experienced intensely by civilians who are otherwise untouched: at once close up and far away. This contributes to heightened consciousness of war, although such spectators are removed from danger. Although interests try to control information flows from and about war, the information environment is huge, shifting and unpredictable. As such, it is impossible to control fully, thereby presenting opportunities for vigorous symbolic struggles involving anti‐war campaigners and others.     

Acquiring technological competencies through inter-organizational collaboration: An organizational learning perspective

Firms are becoming increasingly sophisticated in their technology strategies and are procuring know-how through a variety of collaborative methods including licensing agreements, joint ventures, minority investments, and equity acquisitions. This paper examines the relationship between an organization's learning capability and inter-organizational collaboration in acquiring technological competencies. Organizational learning is posited to be a mediating mechanism through which technological competencies are developed via varying levels of organizational interaction. A general model is developed which suggests an “efficient fit” relationship between an organization's ability to learn, characteristics of the technology, and mode of inter-organizational collaboration. The concept of a “learning gap” is introduced, and managerial implications are suggested. Finally, propositions are developed to facilitate future empirical research.     

Estimating Noncancer Uncertainty Factors: Are Ratios NOAELs Informative?

The prominent role of animal bioassay evidence in environmental regulatory decisions compels a careful characterization of extrapolation uncertainties. In noncancer risk assessment, uncertainty factors are incorporated to account for each of several extrapolations required to convert a bioassay outcome into a putative subthreshold dose for humans. Measures of relative toxicity taken between different dosing regimens, different endpoints, or different species serve as a reference for establishing the uncertainty factors. Ratios of no observed adverse effect levels (NOAELs) have been used for this purpose; statistical summaries of such ratios across sets of chemicals are widely used to guide the setting of uncertainty factors. Given the poor statistical properties of NOAELs, the informativeness of these summary statistics is open to question. To evaluate this, we develop an approach to calibrate the ability of NOAEL ratios to reveal true properties of a specified distribution for relative toxicity. A priority of this analysis is to account for dependencies of NOAEL ratios on experimental design and other exogenous factors. Our analysis of NOAEL ratio summary statistics finds (1) that such dependencies are complex and produce pronounced systematic errors and (2) that sampling error associated with typical sample sizes (50 chemicals) is non-negligible. These uncertainties strongly suggest that NOAEL ratio summary statistics cannot be taken at face value; conclusions based on such ratios reported in well over a dozen published papers should be reconsidered.