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191.
192.
Melamine contamination of food has become a major food safety issue because of incidents of infant disease caused by exposure to this chemical. This study was aimed at establishing a safety limit in Taiwan for the degree of melamine migration from food containers. Health risk assessment was performed for three exposure groups (preschool children, individuals who dine out, and elderly residents of nursing homes). Selected values of tolerable daily intake (TDI) for melamine were used to calculate the reference migration concentration limit (RMCL) or reference specific migration limit (RSML) for melamine food containers. The only existing values of these limits for international standards today are 1.2 mg/L (0.2 mg/dm2) in China and 30 mg/L (5 mg/dm2) in the European Union. The factors used in the calculations included the specific surface area of food containers, daily food consumption rate, body weight, TDI, and the percentile of the population protected at a given migration concentration limit (MCL). The results indicate that children are indeed at higher risk of melamine exposure at toxic levels than are other groups and that the 95th percentile of MCL (specific surface area = 5) for children aged 1–6 years should be the RMCL (0.07 mg/dm2) for protecting the sensitive and general population. 相似文献
193.
From a developmental perspective, workgroups adjust and modify the way they function over time. The present study aims to test, at the group level, the moderating role of the group’s life phase in the relationship between workgroup interdependence ties in terms of task, outcome and functions, assessed by social network density and group satisfaction. A sample of 84 teams from various companies participated in this research. The results showed that the group’s development phase determines the way that outcome interdependence density in teams is associated with satisfaction and reveal the existence of differences between the second and fourth development stages. Therefore, the group’s life cycle stage should be considered as a relevant variable in research and intervention with groups in the workplace. 相似文献
194.
Statistical process monitoring (SPM) is a very efficient tool to maintain and to improve the quality of a product. In many industrial processes, end product has two or more attribute-type quality characteristics. Some of them are independent, but the observations are Markovian dependent. It is essential to develop a control chart for such situations. In this article, we develop an Independent Attributes Control Chart for Markov Dependent Processes based on error probabilities criterion under the assumption of one-step Markov dependency. Implementation of the chart is similar to that of Shewhart-type chart. Performance of the chart has been studied using probability of detecting shift criterion. A procedure to identify the attribute(s) responsible for out-of-control status of the process is given. 相似文献
195.
This study aimed to investigate what decision-making styles might be exhibited by employees who experience burnout. Using a Work Risk Inventory (WRI), developed for this study, which included generic workplace scenarios, it was also explored whether such employees take relatively more risky decisions. Risk was conceptualised as the adoption of decisions that threaten one’s reputation at work, job performance and job security. The mediating effect of the likelihood and seriousness of the consequences of the worst that could happen in each given scenario on the relationships between dimensions of burnout and risk-taking was also tested. A total of 262 employees in various occupations completed an online survey, including measures on burnout, decision-making styles and the WRI. As predicted, dimensions of burnout – exhaustion, cynicism and professional inefficacy – correlated significantly with avoidant decision-making and negatively with rational decision-making. The seriousness of the consequences of the worst-case scenario occurring mediated the relationship between professional inefficacy and risk-taking. In the context of identifying mechanisms by which burnout leads to risky decision-making, the findings suggest that employees’ sense of professional inefficacy determines their risky decision-making. The contribution to theory and implications for practice are discussed. 相似文献
196.
J. J. Roest G. H. P. Van der Helm G. J. J. M. Stams 《Child and Adolescent Social Work Journal》2016,33(5):455-468
This study investigated the longitudinal relation between therapeutic alliance and treatment motivation in a sample of 174 adolescents receiving residential treatment in the Netherlands. Structural equation modeling with a cross-lagged panel design was used to examine the relation between therapeutic alliance and treatment motivation up to 9 months of treatment. Results revealed that autoregressive associations between initial therapeutic alliance and alliance at subsequent time points were significant, whereas for treatment motivation a significant association was found after 6 months, but not after 9 months. Results also showed that a higher level of therapeutic alliance after 3 months was predictive of a higher level of treatment motivation after 6 months. Furthermore, a higher level of therapeutic alliance after 6 months was predictive of a higher level of treatment motivation after 9 months. Implications for research and clinical practice are discussed. 相似文献
197.
This paper proposes new models for locating emergency medical services (EMS) by incorporating survival functions for capturing multiple-classes of heterogeneous patients. The Maximal Expected Survival Location Model for Heterogeneous Patients (MESLMHP) aims to maximize the overall expected survival probability of multiple-classes of patients, whereby different classes could be defined according to agreed patient categories based on response time targets, or by capturing differing medical conditions each with a corresponding survival function. Furthermore, we propose and demonstrate an approximation approach to solving the extended stochastic version of MESLMHP, which utilizes queuing theory to permit the modeling of congestion and utilization at each ambulance station, and does not require assumptions to be made on the utilization of ambulances. Both models are demonstrated using data from the ambulance service in Wales. We show that our multiple outcome measures and survival-maximizing approach, rather than one based on average response time targets alone or a single patient class provides more effective EMS ambulance allocations. 相似文献
198.
P. W. West 《统计学通讯:模拟与计算》2017,46(6):4951-4965
Simulations of forest inventory in several populations compared simple random with “quick probability proportional to size” (QPPS) sampling. The latter may be applied in the absence of a list sampling frame and/or prior measurement of the auxiliary variable. The correlation between the auxiliary and target variables required to render QPPS sampling more efficient than simple random sampling varied over the range 0.3–0.6 and was lower when sampling from populations that were skewed to the right. Two possible analytical estimators of the standard error of the estimate of the mean for QPPS sampling were found to be less reliable than bootstrapping. 相似文献
199.
We examine the role of religion in charitable giving and find that the religious preference of both the donor and the recipient organization influence giving behavior. By exploiting a panel survey of charitable giving, we demonstrate that traditional empirical analysis on charitable giving masks important differences among donor groups. Religious giving by religious individuals is least responsive to changes in price and income, while secular giving by secular individuals has the greatest sensitivity. 相似文献
200.
This study investigates the visual correspondences of gender posing behaviors, specifically exhibited by female figures, between historical European painting and contemporary American photographic advertising. While utilizing Erving Goffman’s Gender Advertisements as an analytical framework, the study focuses on the visual legacy of gender ritualization that is salient in contemporary mass media, proposing five semiotic codes to concretely analyze it. Although Goffman’s gender posing is traditionally associated with female vulnerability and indolence, the study proposes that such qualities are exploited as indicators of luxury within Western visual culture and advertising specifically. It seeks to deconstruct and re-frame the interconnected connotations of luxury and gender display, both expanding Goffman’s framework and providing a unique interpretive resource for critical readers of media texts. 相似文献