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The present study is a result of an interdisciplinary team's work, where a physicist, a family therapist and a developmental psychologist try to share their knowledge and epistemologies. In this kind of conflictual companionship, models of one discipline are tentatively applied to another. This doesn't imply that the different disciplines are isomorphic, but it provides for unusual frames of reference: questions, possibly essential ones, are reformulated in a new language, or in a perspective which was not accessible within the conceptual framework developed for one particular discipline. Our experience is that this kind of effort, in itself a provocative learning experience, is also conducive to original tentative answers in all disciplines involved. Be they of theoretical or experimental nature, it is then up to the specialists of these disciplines to validate the evolved propositions in terms of their own categories.  相似文献   
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Urbanization is a major global change inducing complex and multiple modifications of landscapes and ecosystems. The spatial distributions of organisms experiencing these modifications will likely shift specifically, depending on each species’ response to each environmental modification induced by urbanization. We sampled two ant genera (Lasius and Tetramorium) at 1248 locations along an urbanization gradient in Lyon, France and used high resolution spatial layers for 18 spatial (e.g., open habitat fragmentation, bioclimatic data and surface temperatures) and temporal (e.g., comparison of Normalized Difference Vegetation Index between 1986 and 2015) environmental variables associated with urbanization. Coupling two different analytical methods (Outlying Mean Index and Boosted Regression Trees), we showed that each species’ distribution was influenced by its own combination of environmental factors. Two morphologically cryptic Tetramorium species (T. sp.E and T. sp.U2) were both highly abundant but with opposite responses to urbanization: while T. sp.E was favored by urbanized habitat, T. sp.U2 avoided urbanized areas. Among Lasius species, we detected 63 occurrences of the invasive ant Lasius neglectus, the distribution of which was favored only by embankments along roads. We found that, even at this reduced spatial scale, climatic effects influenced most species and interacted with urbanization factors.  相似文献   
85.
The paper discusses two parallel biocultural trends—aging and inactivity. The principle of economy in movement in modern society versus the dependency of human beings on movement for their development and health is described. The results of inactivity are sometimes mistakenly considered irreversible losses caused by aging, but in actual fact, inactivity accelerates the irreversible losses caused by the aging process. The paper then describes the contribution of physical activity in terms of increasing positive aspects or decreasing risks: increasing life expectancy or decreasing risk of mortality, increasing cardiovascular fitness or decreasing risk of cardiovascular disease, increasing muscle mass or decreasing falls and instability, improving cognitive performance or reducing cognitive decline and neurological disorders, and improving well-being or reducing depression. The optimal dose of physical activity is then described, followed by recommendations for further research on mechanisms determining physical activity behavior.  相似文献   
86.
For first‐time‐in‐human studies with small molecules alternating cross‐over designs are often employed and at study end are analyzed using linear models. We discuss the impact of including a period effect in the model on the precision with which dose level contrasts can be estimated and quantify the bias of least squares estimators if a period effect is inherent in the data that is not accounted for in the model. We also propose two alternative designs that allow a more precise estimation of dose level contrasts compared with the standard design when period effects are included in the model. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
87.
The mean of the Hadamard product of two linear combinations of a random matrix is presented in terms of the mean and variance of the random matrix for any distribution. The variance is given for the normal distribution. Further, the means of four Hadamard products of matrix bilinear forms in a normally distributed random matrix are given. Finally, the mean of a quadruple Hadamard product of linear combinations is derived under normality. Received: January 5, 2000; revised version: April 3, 2000  相似文献   
88.
The frequently large divergences between share price and net asset value (NAV) of listed real estate companies have been a key topic in real estate research for many years. However, previous research has mainly focused on the U.S. market, concentrating on companies’ performance ratios related to information from balance sheet statements and/or income statements as well as information from the stock market, and its results are not satisfying. This study, on the other hand, focuses on the European real estate market and presents a semi-rational model for explaining NAV spreads, taking into account performance ratios and market sentiment simultaneously. It appears that market sentiment in particular substantially improves the model, which explains more than 76% of the NAV spread. Thus, the developed model constitutes a significant improvement over previous studies on the explanation of NAV spreads.  相似文献   
89.
Among the problems raised by admitting statements which are neither true nor false is the problem of how we are to cope with vague concepts. One method of dealing with such concepts has been suggested by Rosser/Turquette (1952), i.e. the employment of a many valued set theory. It is our intention in this paper to discuss the use of many valued logics, especially the set theoretical proposals of Zadeh and Brown, in dealing with this problem. Towards this end, we shall pay close attention to the development of the concepts of fuzzy sets and fuzzy systems. In this regard, it will be argued that Zadeh had in mind a many valued logic where the connectives are interpreted according to Lukasiewicz and Tarski, whereas Brown's version may be based upon a Boolean-valued logic. Furthermore, we shall have occasion to distinguish between two sources of imprecision in specifying the membership of classes, i.e. conceptual vagueness and imprecision due to inexact measurement. Due to Suppes' work in this field, the latter sort of imprecision may be exemplified by providing a theory of the inexact measurement of subjective probability. Finally, we shall discuss some ways in which these two types of imprecision are intertwined.  相似文献   
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