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41.
Summary A substantial explication of the edge effect has been attempted by use of capture-recapture data for a vole population (Microtus montebelli), gathered intwo plots of 100×100 m or less during 12 days, cheked twice daily, in August 1970; the sample was quite sufficient for the aim. The edge effect as guessed by increased catch per trap is usually suspected to ensue from range-settlers in the outside boundary strip of a plot and immigrants. But by a theoretical analysis I could attain a tentative conclusion that no increased catch per trap will occur unless any invasion takes place. Then it follows that, apart from the effect of invasion, the role of the adjoining outside settlers in the edge effect is essentially required to be studied in the light of knowledge on the truth of size and shift in home range. The variation in range behavior for 183 adult voles, captured 6 times or more, could be grouped into eight types, of which the range-conservative type possessed 52% of the sample and the group of the type was justly utilized for giving averages of range size. Besides, it was seen from the observed frequency of types that a considerable number of immigrants onto the census plot were induced perhaps being allured by trap baits, but the majority of them proved to be assigned to the voles that have their ranges inside the assessment line ofDice; the rest referable to effective immigrants was only a few (7%). I could perceive no reason such as disproves the idea ofDice’s additional boundary strip. Viewed from maps of ingress shift of ranges, the effect of ingress must have been greater in the outer trap rows than in the inner within the plot, so that it might well be called edge effect in general; such effect, however, is seen gradually diminishing toward the center, and hence it is almost unlikely that one should find any clear-cut intra-plot assessment lines demarcating such an inner square as quite free from edge effects. Averages of observed range length and width (ORL and ORW), as reliable measures for the true range size, were determined from the above group of specimens; as a result, the remarkable concept of elliptic range shape was established by regarding ORL as long axis and ORW as short one, and, directly from these averages, the mean range sizes worked out at 0.04 for females and 0.09 for males in acreage which proved to be surprisingly well agreeable with those of isotope-revealed ranges for voles given byGodfrey (1954) andAmbrose (1969). The catchability for marked voles ( ) was estimated by the maximum likelihood method by use ofJolly’s formulae (1965), but that for unmarked ones ( ) was made by the regression census formula; as a result it was shown that the population was clearly of π>p type and that the trap-experience that voles underwent one month or more ago can make them retain as high catchability as π. Contribution from JIBP-PT No. 110, carried out by the grant from the expenditure of Education Department to the specific study on “Dynamics of Biosphere”.  相似文献   
42.
Summary Intra- and inter-specific comparisons in progeny size and clutch size were used to identify possible selection pressures acting on three sympatric species of ovoviviporous flesh flies. Both progeny and clutch sizes increased with body weight of the female parent in all species. There was no evidence for a simple trade-off between the two traits. In one species, the larger the female adult the smaller the relative biomass of larvae per clutch (total weight of larvae/body weight of female parent). Female flies produced similar progeny and clutch sizes over successive batches. Variation in progeny size did not influence either larval survival or duration of larval and pupal development. However, larger first instar larvae tended to form larger pupae in two of the species. The experiments testing the effect of progeny size on pupal weight under limited food conditions suggest a selective advantage for larger progeny size.  相似文献   
43.
The process of population extinction due to inbreeding depression with constant demographic disturbances every generation is analysed using a population genetic and demographic model. The demographic disturbances introduced into the model represent loss of population size that is induced by any kind of human activities, e.g. through hunting and destruction of habitats. The genetic heterozygosity among recessive deleterious genes and the population size are assumed to be in equilibrium before the demographic disturbances start. The effects of deleterious mutations are represented by decreases in the growth rate and carrying capacity of a population. Numerical simulations indicate rapid extinction due to synergistic interaction between inbreeding depression and declining population size for realistic ranges of per-locus mutation rate, equilibrium population size, intrinsic rate of population growth, and strength of demographic disturbances. Large populations at equilibrium are more liable to extinction when disturbed due to inbreeding depression than small populations. This is a consequence of the fact that large populations maintain more recessive deleterious mutations than small populations. The rapid extinction predicted in the present study indicates the importance of the demographic history of a population in relation to extinction due to inbreeding depression.  相似文献   
44.
<三国演义>中,有关张飞的人物描写,有一些固定模式的词语.同样的词语也会用在相近人物的身上.日本的军记物语中虽多有人物的衣装描写,却很少有像<三国演义>那样的人物相貌,乃至五官的描写.作为例外,引用中国故事较多的<太平记>在人物描写方法上承接了<三国演义>的影响;而<太平记>中的定型化言语表现又影响到了日本近世翻译成日文的<通俗三国志>.追根溯源,以先行文学中的人物来比喻或说明作品中人物的方法,可以追溯到汉代人物樊哙在<三国演义>中的引用.日中文学之间的承接影响关系研究和比较研究的结合将有助于廓清两国文学之间的交流关系.  相似文献   
45.
This study explored the relationship between perceptions of culturally deviant acts and multicultural experiences of elementary-school children attending an international school in Japan. Findings indicated that children judged a Japanese harsher than a foreigner, irrespective of the children’s age. It was also found that younger children were more susceptible to cultural factors such as their own experience abroad and mother’s activities, which encouraged the formation of less stereotypical images of foreigners.  相似文献   
46.
The article points out the limitations in surveys measuring religiosity and spirituality using the measures developed in Christian or Western contexts. Japanese people think of religion (shūkyō) as revealed religion such as Christianity that has specific doctrinal belief and faith. Through their history of religious regulation, Japanese people came to consider themselves "non-religious" as a way of survival, not to be punished by political authorities and not to be stigmatized in their community. Thus they tend to answer that they consider themselves "non-religious" in surveys, while performing ritual performances for their ancestors in Buddhist temples and Buddhist altars not only to thank ancestors but also to ease the psychological fear people have toward muenbotoke, restless ancestors who have no legitimate offspring to take care of them. To extend the study of spirituality or religiousness in the Japanese context, qualitative studies are necessary not to misinterpret religiousness and spirituality in Japanese context.  相似文献   
47.
It is well known that, under appropriate regularity conditions, the variance of an unbiased estimator of a real-valued function of an unknown parameter can coincide with the Cramér–Rao lower bound only if the family of distributions is a one-parameter exponential family. But it seems that the necessary conditions about the probability distribution for which there exists an unbiased estimator whose variance coincides with the Bhattacharyya lower bound are not completely known. The purpose of this paper is to specify the location, scale, and location-scale parameter family of distributions attaining the general order Bhattacharyya bound in certain class.  相似文献   
48.
For the detection of influential observations on the loading matrix of the factor analysis model, we propose to use the infinitesimal version of two matrix coefficients, including Escoufier (1973)'s also discussed the application in factor analysis of some sensitivity measures used for similar purposes in principal component analysis.  相似文献   
49.
Influence functions are derived for covariance structure analysis with equality constraints, where the parameters are estimated by minimizing a discrepancy function between the assumed covariance matrix and the sample covariance matrix. As a special case maximum likelihood exploratory factor analysis is studied precisely with a numerical example. Comparison is made with the the results of Tanaka and Odaka (1989), who have proposed a sensitivity analysis procedure in maximum likelihood exploratory factor analysis using the perturbation expansion of a certain function of eigenvalues and eigenvectors of a real symmetric matrix. Also the present paper gives a generalization of Tanaka, Watadani and Moon (1991) to the case with equality constraints.  相似文献   
50.
Yutaka Tanaka 《Risk analysis》2004,24(6):1575-1583
The purpose of this study was to verify the validity of a causal model that was made to predict the acceptance of gene-recombination technology. A structural equation model was used as a causal model. First of all, based on preceding studies, the factors of perceived risk, perceived benefit, and trust were set up as important psychological factors determining acceptance of gene-recombination technology in the structural equation model. An additional factor, "sense of bioethics," which I consider to be important for acceptance of biotechnology, was added to the model. Based on previous studies, trust was set up to have an indirect influence on the acceptance of gene-recombination technology through perceived risk and perceived benefit in the model. Participants were 231 undergraduate students in Japan who answered a questionnaire with a 5-point bipolar scale. The results indicated that the proposed model fits the data well, and showed that acceptance of gene-recombination technology is explained largely by four factors, that is, perceived risk, perceived benefit, trust, and sense of bioethics, whether the technology is applied to plants, animals, or human beings. However, the relative importance of the four factors was found to vary depending on whether the gene-recombination technology was applied to plants, animals, or human beings. Specifically, the factor of sense of bioethics is the most important factor in acceptance of plant gene-recombination technology and animal gene-recombination technology, and the factors of trust and perceived risk are the most important factors in acceptance of human being gene-recombination technology.  相似文献   
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