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1.
This study develops a longitudinal perspective on consumer confidence in the safety of food to explore if, how, and why consumer confidence changes over time. In the first study, a theory-based monitoring instrument for consumer confidence in the safety of food was developed and validated. The monitoring instrument assesses consumer confidence together with its determinants. Model and measurement invariance were validated rigorously before developments in consumer confidence in the safety of food and its determinants were investigated over time. The results from the longitudinal analysis show that across four waves of annual data collection (2003–2006), the framework was stable and that the relative importance of the determinants of confidence was, generally, constant over time. Some changes were observed regarding the mean ratings on the latent constructs. The second study explored how newspaper coverage of food safety related issues affects consumer confidence in the safety of food through subjective consumer recall of food safety incidents. The results show that the newspaper coverage on food safety issues is positively associated with consumer recall of food safety incidents, both in terms of intensity and recency of media coverage.  相似文献   

2.
本文综合考虑食品市场竞争环境,消费者食品安全风险规避程度及食品追溯水平等因素建立了食品厂商的双寡头竞争博弈模型,探讨了食品的追溯水平与消费者风险规避程度对食品厂商价格、安全努力水平以及利润的影响。研究发现:食品厂商的最优价格和食品的安全努力水平随其食品追溯水平的提高而增加,随竞争厂商的食品追溯水平的提高而降低;厂商食品追溯水平较高时,其安全努力水平随消费者风险规避程度的增大而提高,其最优价格随高风险规避型消费者比例的增大而增加;而厂商食品追溯水平较低时,其安全努力水平随消费者风险规避程度的增大先增加而后下降,其最优价格随高风险规避型消费者比例的增大总是下降;随高风险规避型消费者比例的增大,各厂商的食品追溯水平对其决策的影响产生不同的变化。  相似文献   

3.
Quantifying safety goals is a key to the regulation of activities which are beneficial on the whole but entail some risks in being performed. Determining compliance with safety goals involves dealing with uncertainties. A recent article by Bier(I) describes some of the difficulties encountered using measures with uncertainty to determine compliance with safety goals for nuclear reactors. This paper uses a hierarchical Bayes approach to address two practical modeling problems in determining safety goal compliance under uncertainty: (1) allowing some modeling assumptions to be relaxed, and (2) allowing data from previous related samples to be included in the analysis. The two issues effect each other to the extent that relaxing some assumptions allows the use of a broader range of data. The usefulness of these changes and their impact on assessing safety compliance for nuclear reactors is shown.  相似文献   

4.
本文针对我国传统化工企业安全生产管理机制治理存在的漏洞,基于Stackelberg博弈模型,对政府部门与化工企业之间进行动态博弈分析。首先针对政府制定安全生产管理机制的策略、针对化工企业确定产量与安全成本的策略,同时引入政府监管检查概率、社会公众监督举报安全事故的概率,以政府部门的社会效益、化工企业的经营效益为支付,分析政府与化工企业的最优反应函数,构建一种新的安全生产管理机制治理研究模型。研究发现,化工企业投入的安全生产管理费用是单位产量可变成本、被政府查处或被社会公众监督举报概率、平均损失、罚款的递增函数。政府制定的平均罚款金额是平均损失、被政府查处或被社会公众监督举报概率的递减函数。化工企业安全成本与生产成本比例的最小值与投入的最大资金呈正相关,与安全事故造成的损害上限呈负相关。通过对博弈模型进行算例分析,发现模拟结果与研究结果相一致。本文的结论可以看作是对当下提高企业安全生产管理机制合理性与有效性的一种思考。  相似文献   

5.
Tunneling excavation is bound to produce significant disturbances to surrounding environments, and the tunnel‐induced damage to adjacent underground buried pipelines is of considerable importance for geotechnical practice. A fuzzy Bayesian networks (FBNs) based approach for safety risk analysis is developed in this article with detailed step‐by‐step procedures, consisting of risk mechanism analysis, the FBN model establishment, fuzzification, FBN‐based inference, defuzzification, and decision making. In accordance with the failure mechanism analysis, a tunnel‐induced pipeline damage model is proposed to reveal the cause‐effect relationships between the pipeline damage and its influential variables. In terms of the fuzzification process, an expert confidence indicator is proposed to reveal the reliability of the data when determining the fuzzy probability of occurrence of basic events, with both the judgment ability level and the subjectivity reliability level taken into account. By means of the fuzzy Bayesian inference, the approach proposed in this article is capable of calculating the probability distribution of potential safety risks and identifying the most likely potential causes of accidents under both prior knowledge and given evidence circumstances. A case concerning the safety analysis of underground buried pipelines adjacent to the construction of the Wuhan Yangtze River Tunnel is presented. The results demonstrate the feasibility of the proposed FBN approach and its application potential. The proposed approach can be used as a decision tool to provide support for safety assurance and management in tunnel construction, and thus increase the likelihood of a successful project in a complex project environment.  相似文献   

6.
With the increased availability of toxicological hazard information arising from multiple experimental sources, risk assessors are often confronted with the challenge of synthesizing all available scientific information into an analysis. This analysis is further complicated because significant between-source heterogeneity/lab-to-lab variability is often evident. We estimate benchmark doses using hierarchical models to account for the observed heterogeneity. These models are used to construct source-specific and population-average estimates of the benchmark dose (BMD). This is illustrated with an analysis of the U.S. EPA Region IX's reference toxicity database on the effects of sodium chloride on reproduction in Ceriodaphnia dubia. Results show that such models may effectively account for the lab-source heterogeneity while producing BMD estimates that more truly reflect the variability of the system under study. Failing to account for such heterogeneity may result in estimates having confidence intervals that are overly narrow.  相似文献   

7.
Accumulating research suggests that the adoption of high performance work practices (HPWPs) is related to organizations' performance. The evidence base is limited by its reliance on retrospective survey reports. This study uses an intervention, including longitudinal interview and survey reports, of the implementation and outcomes of the introduction of HPWPs alongside time series data of objective performance metrics recorded before and after the intervention. The results showed that the implementation of HPWPs was associated with subsequent and sustained increases in productivity and safety performance. The study suggests that a specifically designed intervention involving HPWPs can have beneficial effects both on productivity and safety, but other intermediary variables associated with the implementation process may be critical in mitigating potentially detrimental worker welfare effects arising from work intensification.  相似文献   

8.
9.
ABSTRACT

The rate of occupational injuries has been declining annually, but the rate of decline for fatalities has not kept a similar pace. Behavior-based safety (BBS) contributes to reducing personal injuries, and can be applied to preventing serious incidents. To address serious injuries with greater confidence requires a change in perspective on the causes of fatalities and serious injuries. Heinrich’s safety triangle helps describe the ratio between minor incidents and major incidents, but is not adequate in helping to predict serious incidents. Adding a special subset to the safety triangle can assist safety practitioners in predicting and influencing such events. Extending the triangle to include more foundational root causes, such as leadership shortcomings and system failures, will expand the scope of the behavior analysis, and including greater specificity about the precursors to serious incidents will help the precision of the behavior analysis. The implications of the expanded triangle for amplifying the effectiveness of BBS for reducing serious incidents are discussed.  相似文献   

10.
The number of foodborne diseases has increased in all continents, and efforts must be made to control this urgent and expressive public health problem. This article aims to present and discuss situations related to the compliance and noncompliance of food safety practices (FSPs) in light of Bourdieu's social theory. This qualitative study was conducted in commercial restaurants in two cities in São Paulo, Brazil. Participant observation was used in the restaurants, and notes referring to the kitchen workers and their bosses’ work processes were registered in field journals. Thematic type content analysis was used to determine the meaning cores of field journals. It was found that aspects inherent to convenience and haste at work, deficient infrastructure, lack of employees, negative boss examples, exposure to noise, and body pain experienced by workers can contribute to noncompliance of FSPs and consolidate in the habitus and practical sense some dispositions that can increase the risk of foodborne diseases. This study highlights the necessity of creating environments that address food safety, which means being able to perform a service properly.  相似文献   

11.
The present study investigated older adults’ risk perception, beliefs, and self-perception in the field of kitchen hygiene and food safety. A qualitative study with semi-structured focus groups was conducted. A total of 37 older adults (60–80 years of age) from Germany participated in four focus groups that were stratified by gender. Focus groups covered older adults’ food-handling practices, their perceptions of vulnerability, and their informational needs in the field of food safety. A thematic analysis approach was adopted. The coding categories and subcategories were developed inductively by the researchers based on the data. The coded data were then used to identify overarching themes and subthemes. Main results showed that older adults had confidence in their knowledge and skills with regard to food safety, perceived their post-war generation overall to be resistant and other so-called at-risk groups to be more vulnerable. Moreover, they expressed low informational needs in the area of food safety. The results suggest that age-specific aspects play a role in older adults’ risk perception and highlight the need to develop age-specific risk communication strategies that take into account older adults’ beliefs, knowledge, and informational needs.  相似文献   

12.
High technology organizations need to develop new products or processes that address the dual goals of exploration and exploitation. The competing viewpoints and the asymmetric nature of market returns associated with these goals in R&D projects can heighten stress levels among project team members and reduce their psychological safety. While current research calls for greater focus on task design for improving psychological safety, we know little about how team contextual factors affect this relationship. This study develops and tests a conceptual framework that examines the moderating role of R&D team contextual factors, namely, relative exploration and project‐organization metric alignment on the relationship between a key task design variable, namely, team autonomy, and psychological safety. Relative exploration captures the extent to which exploration goals are emphasized over exploitation goals in an R&D project, while project‐organization metric alignment measures the extent to which project metrics are aligned with broader organizational metrics. Furthermore, we examine the performance consequences of psychological safety in R&D projects. The empirical analysis is conducted using primary data collected from multiple informants across 110 R&D projects in 34 high technology business units. Our results indicate that relative exploration and project‐organization metric alignment have contrasting moderating effects. Furthermore, the effect of psychological safety on project performance is found to be indirect and mediated through team turnover. Implications of the study findings, limitations, and directions for future research are discussed.  相似文献   

13.
A wide range of uncertainties will be introduced inevitably during the process of performing a safety assessment of engineering systems. The impact of all these uncertainties must be addressed if the analysis is to serve as a tool in the decision-making process. Uncertainties present in the components (input parameters of model or basic events) of model output are propagated to quantify its impact in the final results. There are several methods available in the literature, namely, method of moments, discrete probability analysis, Monte Carlo simulation, fuzzy arithmetic, and Dempster-Shafer theory. All the methods are different in terms of characterizing at the component level and also in propagating to the system level. All these methods have different desirable and undesirable features, making them more or less useful in different situations. In the probabilistic framework, which is most widely used, probability distribution is used to characterize uncertainty. However, in situations in which one cannot specify (1) parameter values for input distributions, (2) precise probability distributions (shape), and (3) dependencies between input parameters, these methods have limitations and are found to be not effective. In order to address some of these limitations, the article presents uncertainty analysis in the context of level-1 probabilistic safety assessment (PSA) based on a probability bounds (PB) approach. PB analysis combines probability theory and interval arithmetic to produce probability boxes (p-boxes), structures that allow the comprehensive propagation through calculation in a rigorous way. A practical case study is also carried out with the developed code based on the PB approach and compared with the two-phase Monte Carlo simulation results.  相似文献   

14.
The effectiveness of independent directors is empirically addressed in the Southern European context using a sample of 221 publicly traded firms during the 2001–2007 period. Drawing on the socioemotional wealth approach, we focus on family control and influence to test whether there are significant differences in the effect of independent directors on the firm’s performance among non-family businesses (NFBs) that have a non-family large shareholder, and family businesses (FBs). In doing so, we consider the heterogeneity of FBs by testing whether the FB’s life cycle moderates the effectiveness of independent directors. To that end, we differentiate among founder lead family businesses and non-founder lead family businesses. Moreover, we test whether dual leadership structures, in particular when the family chief executive officer is also the chairperson of the board, moderates the effectiveness of independent directors. A cross-country and panel data design was used, taking into account the endogeneity problem arising in studies of corporate governance. The results show that the contribution of independent directors to a firm’s performance differs for NFBs and FBs. Moreover, findings confirm that in FBs, contribution is moderated by the generational stage of the FB and by the leadership structure of the firm.  相似文献   

15.
This study examines air traffic separations in the service volumes of communication and surveillance facilities that experienced service outages. The data sample consists of 338 unscheduled service outages that happened in 2010 and 2011 at facilities located in the vicinity of 15 major traffic hubs. For each outage, radar track data were collected and used to calculate traffic separations during the period of 30 minutes before to 30 minutes after an outage. Then, the separation index, which indicates the percentage of horizontal separation retained between two aircraft at the same altitude, was estimated. The separation index and loss of separation events were analyzed using lognormal and negative binomial regression models. The results suggest that the count of separation events peaks during the 15 minutes after an outage. In addition, traffic collision avoidance system resolution advisory (TCAS RA) encounters and Category A separation events are 1.31 times more likely during the 30 minutes following the beginning of a service outage, as compared to the 30 minutes before the outage, for both types of facilities. Also, the separation index values are 19% lower following a surveillance facility outage and 4% lower following a communication facility service loss. This study provides evidence that unscheduled service outages of air traffic management facilities are associated with lost or reduced traffic separations and thus can be considered precursors to hazardous loss of separation events.  相似文献   

16.
The safety and security of straits and canals have been playing an important role in maritime transportation. The disruption of a strait or canal will lead to increased transportation costs and world trade problems. Therefore, an advanced approach incorporating fuzzy logic and an evidential reasoning (ER) algorithm is developed to conduct the vulnerability assessment of straits or canals in this paper. A hierarchical structure is first developed taking into account both qualitative and quantitative factors. The fuzzy rule-based transformation technique is applied to convert quantitative factors into qualitative ones, which enables the application of a fuzzy ER method to synthesize all the information from the bottom to the top along the developed hierarchical structure. The software of intelligent decision system (IDS) is used to facilitate the process of vulnerability assessment. The developed framework then is validated and demonstrated in a case study for vulnerability prioritization which can be used as a reference to ensure the safety and security of straits and canals for decision-makers.  相似文献   

17.
Domino effects are low‐probability high‐consequence accidents causing severe damage to humans, process plants, and the environment. Because domino effects affect large areas and are difficult to control, preventive safety measures have been given priority over mitigative measures. As a result, safety distances and safety inventories have been used as preventive safety measures to reduce the escalation probability of domino effects. However, these safety measures are usually designed considering static accident scenarios. In this study, we show that compared to a static worst‐case accident analysis, a dynamic consequence analysis provides a more rational approach for risk assessment and management of domino effects. This study also presents the application of Bayesian networks and conflict analysis to risk‐based allocation of chemical inventories to minimize the consequences and thus to reduce the escalation probability. It emphasizes the risk management of chemical inventories as an inherent safety measure, particularly in existing process plants where the applicability of other safety measures such as safety distances is limited.  相似文献   

18.
《Risk analysis》2018,38(8):1541-1558
Risk analysts are often concerned with identifying key safety drivers, that is, the systems, structures, and components (SSCs) that matter the most to safety. SSCs importance is assessed both in the design phase (i.e., before a system is built) and in the implementation phase (i.e., when the system has been built) using the same importance measures. However, in a design phase, it would be necessary to appreciate whether the failure/success of a given SSC can cause the overall decision to change from accept to reject (decision significance). This work addresses the search for the conditions under which SSCs that are safety significant are also decision significant. To address this issue, the work proposes the notion of a θ‐importance measure. We study in detail the relationships among risk importance measures to determine which properties guarantee that the ranking of SSCs does not change before and after the decision is made. An application to a probabilistic safety assessment model developed at NASA illustrates the risk management implications of our work.  相似文献   

19.
从产品安全责任入手,基于批发价格合同,运用博弈论的基本思想,对四种情景中供应链的均衡进行分析:"非竞争与非激励协调"、"非竞争与激励协调"、"竞争与非激励协调"和"竞争与激励协调"。结果显示:适度的批发价格合同激励协调措施能够提升制造商履行产品安全责任水平、市场需求量、供应链及其各成员的期望收益,但过度激励会降低市场需求量与分销商的期望收益,进而阻滞供应链总期望收益的增加;竞争将降低市场需求量、供应链及其各成员的期望收益;低度激励时竞争将降低制造商履行产品安全责任水平,高度激励时竞争将提升制造商履行产品安全责任水平;供应链采用批发价格合同激励协调机制能够增强其对外部的竞争能力,但过度竞争将降低制造商履行产品安全责任水平,进而对供应链及其各成员的利益造成损害。研究成果对供应链的产品安全责任管理实践有重要的指导意义。  相似文献   

20.
Benchmarking airports is currently popular both in the academic literature and in practice but has proved rather problematic due to the heterogeneity inherent in any reasonably sized dataset. Most studies either treat the airport production technology as a black box, or separate the terminal and airside activities, assessing them individually. In this article we analyze airports as a single unit due to the direct complementarities, thus avoiding the artificial separation of inputs. Using data envelopment analysis (DEA), we open the black box in which a network describes the production process, thus demonstrating the sequential effects that separate final from intermediate outputs, including those under partial managerial control and those that are known to be non-discretionary. To further improve the benchmarking process, we identify appropriate peers for a case study of 43 European airports over 10 years, through a restricted reference mechanism according to pre-defined characteristics. Compared to basic DEA models, the results of the proposed structure provide more meaningful benchmarks with comparable peer units and target values that are potentially achievable in the medium term. By identifying each unit's individual reference set, unique outliers influence the performance measurement less severely than occurs under basic DEA. In addition, the formulations produce an implementation path that moves the airport towards the Pareto frontier gradually, taking into account the regulatory and business environment in which the unit is located.  相似文献   

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