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981.
This work presents an extension of the slash Lindley–Weibull distribution, of which it can be considered a modification. The new family is obtained by using the quotient of two independent random variables: a two-parameter Lindley–Weibull distribution divided by a power of the exponential distribution with parameter equal to 2. We present the pdf and cdf of the new distribution, analyzing their risk functions. Some statistical properties are studied and the moments and coefficients of asymmetry and kurtosis are shown. The parameter estimation problem is carried out by the maximum likelihood method. The method is assessed by a Monte Carlo simulation study. We use nutrition data, which are characterized by high kurtosis, to illustrate the usefulness of the proposed model.  相似文献   
982.
Public Organization Review - Globally, ageing civilian nuclear plant and their toxic wastes are in need of decommissioning and disposal as operational lives end. In the UK, a legacy (DTI 2002) of...  相似文献   
983.
984.
The continued expansion and fragmentation of biological disciplines impede education, communication, and efficient advance of biological research. Reversing these trends may require a unification of theories and concepts from all levels of biological organization. One form of this unification is the statement of generalizations that apply to all living systems. We explore the philosophical foundations of general theories of living systems by analyzing conceptual frameworks as they apply to biology. This analysis examines the relation of empirical observation, theories, and conceptual frameworks within the context of an individual scientist's conceptual continuum. Also presented are a small set of translevel generalizations that articulate our conceptual framework of living systems in terms of organismic system organization, the environmental system-organismic system dyad, system capacity, and system incorporation. A set of procedural rules are stated which suggest minimum criteria for the evaluation of the explanatory adequacy of biological theories. The relation of this work to other similar analyses and syntheses of biological knowledge is discussed.  相似文献   
985.
The views of a sample of Australian teachers were obtained regarding the powers exercised by teachers and administrators in decisions relevant to internal school government. The teachers perceived themselves as playing a delegated-leadership role within the classroom and a subordinate role in decision areas external to classroom management. On the other hand, they expressed a desire to extend their delegated-leadership role to important matters concerning the instructional organization and administration of the school. The evidence suggested that teachers wished to change the perceived balance of power in schools in the direction of a more ‘democratic’ style of school government.  相似文献   
986.
987.
The argument in this paper rests on the assumption that the prime objective of any corporate activity must in some way be related to a profitability goal, however this may be measured, however this may be defined, and however this may be constrained by the relevance of a times-cale.

The paper makes some comments on the selection of a corporate objective or goal but mainly it considers the direct contribution that financial management can make to achievement of this goal. It distinguishes this from the accounting rôle which is more appropriately concerned with measuring and monitoring progress towards the goal.  相似文献   

988.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.  相似文献   
989.
Conventional parametric representations of stable law distributions do not allow all members of the family to be obtained as continuous limits of the parameters. Model building (or simulation) using such representations will be numerically unstable near such limits in consequence. Existing tables are not satisfactory near such limits as interpolation cannot be carried out. We show that these difficulties are overcome by using a new shifted Cartesian representation which characterizes the entire stable law family in a completely continuous way. Standardization is still possible with this representation so that tabulation, using just two bounded parameters, can be carried out. Its use is illustrated in a non-regular threshold estimation problem involving stable distributions which are discontinuous limits in conventional representations.  相似文献   
990.
Abstract Objective: This study aimed to understand the gaps in college students' knowledge regarding sexual health information. Participants: A sample of 242 participants enrolled in an introductory college course participated in this study in the Fall 2009 semester. Methods: Students participated in 1 of 2 brief interventions and wrote a response paper about their experience. The papers were analyzed using conventional content analysis for information that was new to participants by looking for key words that suggested learning took place. Results: The findings indicated that the majority of participants learned new information. Most learning occurred regarding sexually transmitted infections (ie, types, symptoms, prevalence, treatment, testing) and correct condom use. There were also demographic differences regarding reported new information. Conclusions: Findings can be used to develop future sex education programs for college students by providing college educators with an understanding of where students lack knowledge of sexual health.  相似文献   
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