To maximize the ecological services of urban forests, a better understanding of the effects of urbanization on urban forest characteristics, landscape metrics, and their associations is needed for landscape-related regulations in space-limited green infrastructure of metropolitan regions. In this study, Harbin, a typical fast-growing provincial-capital city in Northeast China, is used as a case study. Based on remote sensing images, field surveys, and correlation and variation partitioning analyses, we conclude that landscape characteristics and forest attributes have large variations among different urbanization intensity (UI) regions. Forest patch density (PD), landscape shape index, woody plants species richness, and the Shannon–Wiener index (H′) increased linearly, while stem section area and tree height decreased linearly with the increasing of UIs. UI had a greater influence on tree size and forest community attributes than the forest landscape pattern. Accordingly, any landscape regulation on forest attributes should be implemented according to UIs. In addition, Euclidean nearest neighbor distance(ENN-MN), mean perimeter-area ratio (PARA-MN), fractal dimension index(FRAC-MN), and PD could probably indicate forest attributes the most, e.g., the increase of PARA-MN may be accompanied with taller trees in low and heavy UI regions, but lower woody plants species evenness in low and medium UI regions. More diversified woody plants species, and afforested areas should be advocated in a low UI region, while in a heavy UI region, the conservation of large trees should be implemented. Our results highlight that the implementation of urban forest management should vary according to different urbanization regions to maximize ecological services.
This paper is concerned with planning work-center capacity levels in manufacturing firms that employ a material requirements planning (MRP) system. It presents four procedures for developing work-center capacity plans designed to insure the production of components and assemblies as specified by the MRP plan and the master production schedule (MPS). These procedures (capacity planning using overall factors, capacity bills, resource profiles, and capacity requirements planning) are compared using simulation analysis. The results indicate that the performance of a procedure when measured against the MPS depends on the operating conditions of the manufacturing system. The results also indicate that the choice of a particular procedure often represents a compromise among the benefits of improved MPS performance, the costs of preparing and processing data, and the premium expenses required for more frequent adjustments in work-center capacity levels. 相似文献
This paper examines forecast error with an intention not to minimize forecast error so much as to bias the resultant error in order to achieve better managerial results. Much work has been accomplished by other researchers toward the goal of minimizing forecast error—sometimes by the use of sophisticated forecasting techniques. The results of this paper indicate that manipulating forecast error bias may be the better managerial strategy as opposed to going to great lengths to minimize forecast error. Subject Areas: Forecasting, Aggregate Planning, Capacity Planning, and Production/Operations Management. 相似文献
The present study uses canonical analysis to examine the contingency model of organizations in the nursing home field. Data on environmental pressures and managerial practices relevant to the decision-making process are analyzed. Results support the theory that managerial practices are contingent on environmental pressures. The implications of these results for health-care decision makers and for future assessments of managerial-environmental relationships are discussed. 相似文献
Research suggests the relationship between pleasure and condom use during penile–vaginal intercourse (PVI) is associated with relationship status. This online study examined pleasure ratings and condom use at last PVI, stratifying by partner type, among a national sample of Canadian university students. Participants were 715 undergraduates (60.7% women, 39.3% men) who reported on their most recent sexual experience. Condom use decreased with level of relationship commitment, whereas ratings of pleasure increased. Overall, participants were more likely to rate their most recent PVI as Very pleasurable when condoms were not used compared to when condoms were used. However, when stratified by partner type, these differences largely disappeared. For women, with one exception, there were no differences in pleasure between PVI with and without condoms across most partner-type categories. Women in committed dating relationships were more likely to report their last PVI as very pleasurable if condoms were not used than women in these same relationships who had used condoms. Across relationship categories, men who did and did not use condoms did not differ in terms of their pleasure ratings. The results of this study suggest relationship context should be taken into account when assessing condom use experiences. 相似文献
This article presents a historical sociological case study of sexual oppression within the early nineteenth-century foundation period of a French Roman Catholic male religious order, the Marist Brothers, founded in 1817. The different sexualities of two rival founder figures, the priests Jean-Claude Courveille and Marcellin Champagnat, the former homosexual, the latter heterosexual, found expression in radically divergent conceptions of the religious habit. For Courveille, the costume design for the Brothers was ostentatious and stylish; for Champagnat, it was sober and clericalised. This archive-based investigation shows how Courveille's sexual orientation led to his fall from grace within the Church and the suppression of his sartorial self-expression. Champagnat, whose conventional dress rules prevailed, became a canonized saint. In the victory of the orthodox sacred dress code, the ideology of ‘clerical masculinism’ weaves its hegemonic power over the bodies of ‘men of the cloth’. 相似文献
The financial world is in meltdown—and it is the fault of modern financial theory. How did the theorists manage to believe so many impossible things for so long? William Janeway marvels and explains. 相似文献
The 2000 census of China has several notable innovations, including a sample long form containing detailed items on migration, housing, and employment. Preliminary data indicate rapid urbanization and continued rapid social change in the 1990s, and apparent success in the government's drive to curtail population growth. Although a post‐enumeration survey indicates that overall data quality is good, the rise of a mobile “floating population” and pressures of the birth planning program caused problems for the enumeration of migrants and infants. Data released to date have been silent on two important issues, fertility and rising sex ratios. 相似文献
Two related streams of criticism of the analytic hierarchy process (AHP) have not yet been satisfactorily resolved, although both date from the early 1980s. The first relates to ambiguity in the meaning of the relative importance of one criterion as compared to another. The second is concerned with reversals of rank alleged to be possible when new options are introduced in an AHP problem. Both proponents and critics of AHP agree that rank reversals occur, but disagree on the legitimacy of such reversals. This paper shows that there is a necessary correspondence between the manner in which criteria importances are interpreted and computed and the manner in which the weights of the options under each criterion are normalized. In general, if this relationship is ignored, incorrect weights are generated for options under consideration regardless of whether new options are added or deleted. A rank reversal on the addition of an option is merely symptomatic of this fact, and such reversals do not occur when the correspondence condition is met. 相似文献