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251.
Earlier work found evidence for geographic linkages of aggregate foreign direct investment across countries and country‐pairs. From a theoretical point of view, such linkages at the macroeconomic level may root in between‐firm as well as within‐firm linkages and originate from information spillovers across or within firms in exploring unknown markets, and vertical linkages between production plants across different locations within the firm. We use data on the universe of German multinational enterprises (MNEs) to empirically explore how marginal investments at one foreign affiliate depend on investments at other affiliates within the same MNE. The empirical approach employs two channels or modes of cross‐affiliate interdependence: mere geography (capturing horizontal linkages through correlated learning and horizontal competition within the firm) and input–output relationships within or across industries (which capture vertical linkages). Adding to earlier findings at the aggregate level, we find evidence of a significant interdependence of investments within the firm. In the firm‐level data at hand, vertical linkages appear to be more important than horizontal ones. Investments at one location tend to stimulate investments at other locations of the same MNE, particularly if input linkages are strong. The opposite seems to be true for output linkages. Beyond vertical linkages, mere geographic proximity matters only to a minor extent. This suggests that evidence of linkages through geographic closeness at aggregate data levels accrue mainly to reasons of vertical linkages within networks of affiliates. (JEL C31, D22, F21, F23, F68, G31, H32) 相似文献
252.
Adam C. Jones W. David Robinson Ryan B. Seedall 《Journal of marital and family therapy》2018,44(4):606-623
In a study of 142 couples, we gathered survey data to show how sexual communication influences sexual and relationship satisfaction as well as sexual and orgasm frequency. In two dyadic data path analyses, we observed the significant paths of influence that sexual communication has on sexual and relationship satisfaction, as well as sexual and orgasm frequency. Our findings revealed greater amounts of sexual communication were associated with increased orgasm frequency in women and greater relationship and sexual satisfaction in both sexes. We also observed important differences in the associations of sexual communication and general communication on satisfaction levels. With these analyses, we expand the current literature to broaden our understanding of the role that sexual communication plays in committed relationships. 相似文献
253.
Attempts to control the importation of infectious diseases through the medical screening and evaluation of immigrants and refugees represent the modern application of some of the earliest recorded public health interventions.
States with long-standing immigration programmes continue to require the medical examination and screening of migrants for certain diseases. In some instances, the public health effectiveness of these immigration medical assessments is of questionable value when considered from a population health basis.
This article reviews current practices and describes recent studies where more modern and epidemiologically based immigration medical interventions have been undertaken. A more effective immigration medical assessment process is proposed through the use of results of this more empirical approach to immigration medical screening. 相似文献
States with long-standing immigration programmes continue to require the medical examination and screening of migrants for certain diseases. In some instances, the public health effectiveness of these immigration medical assessments is of questionable value when considered from a population health basis.
This article reviews current practices and describes recent studies where more modern and epidemiologically based immigration medical interventions have been undertaken. A more effective immigration medical assessment process is proposed through the use of results of this more empirical approach to immigration medical screening. 相似文献
254.
This paper presents a model and an algorithm for scheduling a system in which parts are processed through a chemical processing tank line. The tank line is equipped with one piece of material-handling equipment. The tank line is modelled with a mixed integer linear programming formulation. The formulation is then used to develop a heuristic algorithm. The algorithm generates the optimum or near optimum schedule and is easy to apply in practice where no defectives are permitted. 相似文献
255.
Dankmar Böhing 《Statistics》2013,47(4):487-495
Tn optimal experimental design theory there are well-known situations, in which additional constraints are implied to the design set. These constraints destroy in general the simplex structure of the set of feasible points of the design set. Thus the available iteration procedures for the unrestricted case are no longer applicable. In this paper a penalty approach is suggested which transforms the restricted problem to the unrestricted case and allows the application of well-known algorithms such as the Fedorov-Wynn-type or the projected gradient procedure. 相似文献
256.
The study uses an eclectic framework and through an intersectional analysis and use of narratives explores the meaning of janitorial work, the gender division of labour (GDL), the unions and organizing for janitors engaged in industrial cleaning for a big cleaning company, Pluto, in Toronto. Pluto was organized by the Service Employees International Union (SEIU) in 2006. The study is based on the organizing drive for Pluto and uses participant observation and interview methods. Intersectional analysis is useful in understanding the worker's perceptions of the racialized, gendered and classed constitution of cleaning work as ‘dirty’ and their resistance to these constructs. We explore GDL in industrial cleaning and the construction of women's work as ‘light duty’ and men's work as ‘heavy duty’. We conclude that union membership is important not only for material benefits of the janitors but also for their alternative identity construction. However, there is a persistence of GDL and gender pay equity is not addressed seriously in the organizing drive or upon organizing. 相似文献
257.
K. Hoelzer Y. Chen S. Dennis P. Evans R. Pouillot B. J. Silk I. Walls 《Risk analysis》2013,33(9):1568-1581
Listeria monocytogenes is a leading cause of hospitalization, fetal loss, and death due to foodborne illnesses in the United States. A quantitative assessment of the relative risk of listeriosis associated with the consumption of 23 selected categories of ready‐to‐eat foods, published by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture in 2003, has been instrumental in identifying the food products and practices that pose the greatest listeriosis risk and has guided the evaluation of potential intervention strategies. Dose‐response models, which quantify the relationship between an exposure dose and the probability of adverse health outcomes, were essential components of the risk assessment. However, because of data gaps and limitations in the available data and modeling approaches, considerable uncertainty existed. Since publication of the risk assessment, new data have become available for modeling L. monocytogenes dose‐response. At the same time, recent advances in the understanding of L. monocytogenes pathophysiology and strain diversity have warranted a critical reevaluation of the published dose‐response models. To discuss strategies for modeling L. monocytogenes dose‐response, the Interagency Risk Assessment Consortium (IRAC) and the Joint Institute for Food Safety and Applied Nutrition (JIFSAN) held a scientific workshop in 2011 (details available at http://foodrisk.org/irac/events/ ). The main findings of the workshop and the most current and relevant data identified during the workshop are summarized and presented in the context of L. monocytogenes dose‐response. This article also discusses new insights on dose‐response modeling for L. monocytogenes and research opportunities to meet future needs. 相似文献
258.
In the Bayesian analysis of a multiple-recapture census, different diffuse prior distributions can lead to markedly different inferences about the population size N. Through consideration of the Fisher information matrix it is shown that the number of captures in each sample typically provides little information about N. This suggests that if there is no prior information about capture probabilities, then knowledge of just the sample sizes and not the number of recaptures should leave the distribution of Nunchanged. A prior model that has this property is identified and the posterior distribution is examined. In particular, asymptotic estimates of the posterior mean and variance are derived. Differences between Bayesian and classical point and interval estimators are illustrated through examples. 相似文献
259.
The performance of a tandem automated guided vehicle (AGV) system is compared with that of conventional AGV track systems. In the tandem system the track is divided into non-overlapping, single-vehicle closed loops. Using simulation it is shown that, because of trips requiring delivery across loops, the tandem system has a higher expected travel time per load and thus a greater average time in system. When the loads are delivered within the original loop only, the tandem system has a lower average time in system than in conventional systems, although the difference is modest. Track layout appears to influence the average time in system much more than docs the dispatching rule invoked. The success of the tandem system is highly dependent on approximately even AGV utilization, which may be difficult to obtain in practice. 相似文献
260.