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1.
Annual concentrations of toxic air contaminants are of primary concern from the perspective of chronic human exposure assessment and risk analysis. Despite recent advances in air quality monitoring technology, resource and technical constraints often impose limitations on the availability of a sufficient number of ambient concentration measurements for performing environmental risk analysis. Therefore, sample size limitations, representativeness of data, and uncertainties in the estimated annual mean concentration must be examined before performing quantitative risk analysis. In this paper, we discuss several factors that need to be considered in designing field-sampling programs for toxic air contaminants and in verifying compliance with environmental regulations. Specifically, we examine the behavior of SO2, TSP, and CO data as surrogates for toxic air contaminants and as examples of point source, area source, and line source-dominated pollutants, respectively, from the standpoint of sampling design. We demonstrate the use of bootstrap resampling method and normal theory in estimating the annual mean concentration and its 95% confidence bounds from limited sampling data, and illustrate the application of operating characteristic (OC) curves to determine optimum sample size and other sampling strategies. We also outline a statistical procedure, based on a one-sided t-test, that utilizes the sampled concentration data for evaluating whether a sampling site is compliance with relevant ambient guideline concentrations for toxic air contaminants.  相似文献   
2.
洛阳有伊、洛、、涧、谷等数条河流。唐代东都洛阳水灾频繁发生 ,共 35次之多 ,平均不足 1 0年一次 ,给洛阳城及沿岸造成严重破坏和损失。洛阳水灾发生多为五至八月份。唐代洛阳河流具有明显的季节性 ,雨季流量大 ,便于行舟 ,旱季水少河浅难以行船。针对频发的水灾 ,唐政府采取了一系列救助灾民的措施 ,同时还采取了加固堤坝、疏浚河道等防治措施  相似文献   
3.
美国与日本战争赔偿方式的演变   总被引:3,自引:1,他引:2  
战后日本战争赔偿方式在美国的控制下先后经历了从实物赔偿到劳务赔偿再到资本赔偿的变迁。随着对东南亚的赔偿最终被纳入美国东亚遏制政策的轨道 ,日本得以将惩罚性的战争赔偿转变为一种有效的经济外交手段  相似文献   
4.
Many optimisation problems arise in managing the Blood Donation (BD) supply chain. Most of them have been addressed in the literature, while other problems, e.g. donation scheduling, have not been sufficiently addressed so far. However, blood collection from donors may have a disruptive impact on the entire BD supply chain if not properly managed. For example, scheduling donation appointments based on some system metrics may improve the flow of blood units through the BD supply chain and increase the quality of service perceived by donors. In this short communication, we present the donation scheduling problem and highlight the lack of work in the literature that deals with this problem. Then, we analyse the impact of an unbalanced flow of blood units on the BD system and the benefits that may derive from a suitable appointment scheduling. Finally, we propose suggestions for future research in BD collection scheduling that may improve the BD process.  相似文献   
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This article is about ‘coming out’ and the process of disclosure of queer migrants within their transnational families. Despite debates about the decreasing relevance of coming out in contemporary western societies, we argue that the process of coming out continues to be a central mode of belonging and identity construction for queers in the context of transnational migration. Interviews with migrants from Poland, Russia and Turkey in Germany on their coming out experiences show that people rely on a variety of boundaries, i.e. gender, class and ethnicity, to construct a desired way of life. Theoretically, these insights indicate the need to reframe post-structuralist theories on power, most prominently advanced by Pierre Bourdieu and Michel Foucault, from an intersectional perspective. The findings in this paper pinpoint to the challenges of transnational social life queer migrants are confronted with through empirical illustrations of perceptions of differences and ambiguities between immigration and emigration contexts. Furthermore, we advocate that sexuality is a crucial dimension of migration processes determining self-definition in relation to people and places, which makes their stories of coming out always also stories of ‘coming home’.  相似文献   
7.
The binary logistic regression is a widely used statistical method when the dependent variable has two categories. In most of the situations of logistic regression, independent variables are collinear which is called the multicollinearity problem. It is known that multicollinearity affects the variance of maximum likelihood estimator (MLE) negatively. Therefore, this article introduces new shrinkage parameters for the Liu-type estimators in the Liu (2003) in the logistic regression model defined by Huang (2012) in order to decrease the variance and overcome the problem of multicollinearity. A Monte Carlo study is designed to show the goodness of the proposed estimators over MLE in the sense of mean squared error (MSE) and mean absolute error (MAE). Moreover, a real data case is given to demonstrate the advantages of the new shrinkage parameters.  相似文献   
8.
In Turkey, there is a shortage of studies on the prevalence of sexual aggression among young adults. The present study examined sexual aggression victimization and perpetration since the age of 15 in a convenience sample of N = 1,376 college students (886 women) from four public universities in Ankara, Turkey. Prevalence rates for different coercive strategies, victim-perpetrator constellations, and sexual acts were measured with a Turkish version of the Sexual Aggression and Victimization Scale (SAV-S). Overall, 77.6% of women and 65.5% of men reported at least one instance of sexual aggression victimization, and 28.9% of men and 14.2% of women reported at least one instance of sexual aggression perpetration. Prevalence rates of sexual aggression victimization and perpetration were highest for current or former partners, followed by acquaintances/friends and strangers. Alcohol was involved in a substantial proportion of the reported incidents. The findings are the first to provide systematic evidence on sexual aggression perpetration and victimization among college students in Turkey, including both women and men.  相似文献   
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10.
Transformational leaders are known to inspire and motivate their followers, thereby leading to enhanced job satisfaction. Job satisfaction is an intellectual concept regarding individuals’ attitudes toward their jobs. This study asserts that the underlying mechanisms for transformational leadership to affect employee satisfaction are trust in the community, including the leader (that is, organization) and trust in the self, namely self‐efficacy. Leadership is specifically associated with continual transformations in the higher educational context, and collectivist cultures may manifest different processes underlying the transformational leadership–satisfaction relationship. This study investigated the mediating effects of trust and self‐efficacy on the relationship between transformational leadership and job satisfaction. The study sample included academicians from a nonprofit higher education institution in Turkey. The data were analyzed using structural equation modeling. The results showed that the relationship between transformational leadership and job satisfaction is fully mediated by both trust and self‐efficacy. The mediator effect of trust was shown to be stronger than self‐efficacy, which is assumed to be the result of the cultural context. The results are discussed in the context of employee satisfaction and cultural determinants of employee satisfaction.  相似文献   
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