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51.
数百年来,马尼拉、澳门和广州一直相互依存,保持着密切关系。从16世纪后期至今,三者有着紧密的互动关系,每一城市对其他两者都有着深刻的影响与冲击。这些联系已经维系了几百年,直到今天仍有数万菲律宾人在珠江三角洲生活和工作。牛痘传入澳门和广州或许是巴尔米斯环球之旅的意外收获,但它也确实是三个地区之间长期密切关系的一个表现。在巴尔米斯来到珠江三角洲200周年之际,我们不应忘记三地人民之间在历史上的紧密关系,这一关系仍继续支持和维系着中菲两国,它也将把我们带向未来。  相似文献   
52.
This paper analyzes the cost increases due to demand uncertainty in single-level MRP lot sizing on a rolling horizon. It is shown that forecast errors have a tremendous effect on the cost effectiveness of lot-sizing techniques even when these forecast errors are small. Moreover, the cost differences between different techniques become rather insignificant in the presence of forecast errors. Since most industrial firms face demand uncertainty to some extent, our findings may have important managerial implications. Various simulation experiments give insight into both the nature and the magnitude of the cost increases for different heuristics. Analytical results are developed for the constant-demand case with random noise and forecasting by exponential smoothing. It is also shown how optimal buffers can be obtained by use of a simple model. Although the analysis in this paper is restricted to simplified cases, the results merit further consideration and study. This paper is one of the first to inject forecast errors into MRP lot-sizing research. As such it attempts to deal with one of the major objections against the practical relevance of previous research in this area.  相似文献   
53.
Alter G  Dribe M  Van Poppel F 《Demography》2007,44(4):785-806
Researchers from a number of disciplines have offered competing theories about the effects oJ childbearing on parents 'postreproductive longevity. The "disposable soma theory" argues that investments in somatic maintenance increase longevity but reduce childbearing. "Maternal depletion" models suggest that the rigors of childrearing increase mortality in later years. Other researchers consider continued childbearing a sign of healthy aging and a predictor of future longevity. Empirical studies have produced inconsistent and contradictory results. Our focus is on the experience of widowhood, which has been ignored in previous studies. We hypothesize that the death of a spouse is a stressful event with long-term consequences for health, especially for women with small children. Data are drawn from historical sources in Sweden, Belgium, and the Netherlands from 1766 to 1980. Postreproductive mortality was highest among young widows with larger families in all three samples. Age at last birth had little or no effect. We conclude that raising children under adverse circumstances can have long-lasting, harmful effects on a mother's health.  相似文献   
54.
Networks of ambient monitoring stations are used to monitor environmental pollution fields such as those for acid rain and air pollution. Such stations provide regular measurements of pollutant concentrations. The networks are established for a variety of purposes at various times so often several stations measuring different subsets of pollutant concentrations can be found in compact geographical regions. The problem of statistically combining these disparate information sources into a single 'network' then arises. Capitalizing on the efficiencies so achieved can then lead to the secondary problem of extending this network. The subject of this paper is a set of 31 air pollution monitoring stations in southern Ontario. Each of these regularly measures a particular subset of ionic sulphate, sulphite, nitrite and ozone. However, this subset varies from station to station. For example only two stations measure all four. Some measure just one. We describe a Bayesian framework for integrating the measurements of these stations to yield a spatial predictive distribution for unmonitored sites and unmeasured concentrations at existing stations. Furthermore we show how this network can be extended by using an entropy maximization criterion. The methods assume that the multivariate response field being measured has a joint Gaussian distribution conditional on its mean and covariance function. A conjugate prior is used for these parameters, some of its hyperparameters being fitted empirically.  相似文献   
55.
56.
This paper develops a novel and efficient algorithm for Bayesian inference in inverse Gamma stochastic volatility models. It is shown that by conditioning on auxiliary variables, it is possible to sample all the volatilities jointly directly from their posterior conditional density, using simple and easy to draw from distributions. Furthermore, this paper develops a generalized inverse gamma process with more flexible tails in the distribution of volatilities, which still allows for simple and efficient calculations. Using several macroeconomic and financial datasets, it is shown that the inverse gamma and generalized inverse gamma processes can greatly outperform the commonly used log normal volatility processes with Student’s t errors or jumps in the mean equation.  相似文献   
57.
Objective: To examine differences in complete response rates for depression screening questions based on demographic characteristics. Methods: Cross-sectional study examining associations between demographic characteristics and completely responding depression-screening questions. Participants: “Healthy Minds Study” data, collected in a public University in February 2016, where 7,326 students participated. Results: women (AOR: 0.69; 95% CI =0.57–0.83) and gay/lesbian students (AOR: 0.24; 95% CI =0.10–0.60) had better complete response rates. Non-US (AOR: 1.46; 95% CI =1.03–2.07), black (AOR: 3.32; 95% CI =1.92–5.77), and Middle-Eastern students (AOR: 3.73; 95% CI =1.73–8.02) had lower complete response rates. Conclusions: Our study shows sex, gender, citizenship, and race categories have significant differences in complete response rates for the outcome. Our findings have several implications; including recognizing interventions for depression based on responders may not target those that tend to be “partial-responders”. Efforts in survey design, recruiting and completion of surveys should be maximized.  相似文献   
58.
This study examined the clinical significance of career counseling effects. Participants were 111 university students (83% women) who participated in individual career counseling sessions at their university. All participants completed the French version of the Outcome Questionnaire–30.2 (OQ‐30.2; Lambert, Finch, Okiishi, & Burlingame, 2005) immediately before the 1st session (pretest) and at the beginning of the last session (posttest). The OQ‐30.2 assesses 3 client life domains: subjective discomfort, problems in interpersonal relationships, and problems in social role satisfaction. Using Jacobson and Truax’s (1991) statistical approach to assessing clinical change, the authors compared clients’ pretest OQ‐30.2 scores with their posttest scores. Among clients with a “dysfunctional” score (n = 59) at the study’s inception, 34% recovered and 14% improved, whereas 41% of clients with functional scores (n = 52) at the study’s inception improved. The results suggest that individual career counseling can make a difference in the lives of many clients; they also highlight the importance of further outcome research that accounts for possible variability in clients’ responses to career counseling.  相似文献   
59.
This paper focuses on a Christian model of leprosy care overseen by Catholic nuns in Quy Hòa, a leprosarium in South Central Vietnam, from 1929—when the leper colony was established—until 1975, when the American-backed Southern regime collapsed and all of Quy Hòa’s foreign nuns were forced to leave. Drawing on recollections of elderly residents of the former leprosy colony, it describes the close and loving attention that the nuns offered to inmates, an attentiveness that was informed by the nuns’ ethic of Christian sacrifice. The nuns at Quy Hòa successfully built a quasi parent–child relationship with leprosy-afflicted inmates. Their striking devotion to the ‘lepers’ resembles substitute motherhood. However, these recollections of that era also shed critical light on an approach to leprosy care that was premised on hierarchy, strictly enforced segregation from the wider community and pronounced paternalism towards all those who came under the nuns’ rule of care.  相似文献   
60.
When parents divorce, grandparents can play a supportive role in the lives of their grandchildren, but a parental divorce may also put grandchild–grandparent ties under pressure. In this study the authors investigated how grandchildren of married and divorced parents differ in the frequency of face‐to‐face contacts with grandparents and how this is mediated by postdivorce residence arrangements. Based on the multi‐actor survey “Divorce in Flanders,” they used reports of contact provided by more than 1,000 grandchildren and compared them with more than 1,100 grandparent reports for validation. The results showed that grandchildren from divorced parents have fewer contacts with their grandparents than grandchildren whose parents are married but that it is the postdivorce residence arrangement of grandchildren that produces this result. When grandchildren live with their divorced father or in a shared residence arrangement, they even see paternal grandparents more often than grandchildren with married parents.  相似文献   
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