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991.
The participation of external technical experts in the development of risk assessment documents and methodologies has expanded and evolved in recent years. Many government agencies and authoritative organizations have experts peer review important works to evaluate the scientific and technical defensibility and judge the strength of the assumptions and conclusions (OMB, 2004; IPCS, 2005; IARC, 2006; Health Canada, 2007; U.S. EPA, 2006). Expert advice has been solicited in other forms of peer involvement, including peer consultation in, for example, the U.S. EPA's Voluntary Children's Chemical Evaluation Program (VCCEP). This article discusses how the principles and practices of peer review can be extended to other types of peer involvement activities (i.e., peer input and peer consultation) to develop high-quality risk assessment work products. A comprehensive process for incorporating peer input, peer consultation, and peer review into risk assessment science is outlined. Four key principles for peer involvement-independence, inclusion of appropriate experts, transparency, and a robust scientific process-are discussed. Recent examples of peer involvement in the development of Health Canada's Priority Substances and Domestic Substance List (DSL) programs under the Canadian Environmental Protection Act (CEPA) serve to highlight the concepts.  相似文献   
992.
让我们想象这样一幅场景:一位人类学家来到你的办公室,他用了一整天时间跟在你身边,寸步不离地观察你的一言一行。当你一天工作结束之后,他告诉你,在这一整天当中,他只看到了一件事情——人们在不停地进行沟通。这位人类学家告诉你,在这一天的时间里,他参加了一些正式的会议,看到人们在进行面对面的交流,进行随机的讨论,或者是通过电子邮件进行沟通。“没错,确实如此,”你说道,“可那叉怎样呢?”人类学家告诉你,你在这一天当中所说的话大多数都是重复的。“这很好,”你告诉自己,  相似文献   
993.
This paper reports on an investigation into strategic project management in the UK upstream oil and gas sector. The management process is represented by a set of elements which covers context, content and output and are balanced across financial, internal business, external environment, and learning and innovation perspectives. The paper uncovers elements that appear to explain successful project management and compares these with the elements to which managers pay greatest attention. There appears to be a mismatch between those elements which are associated with success and those receiving significant management attention.  相似文献   
994.
Supply chain disruptions and the associated operational and financial risks represent the most pressing concern facing firms that compete in today's global marketplace. Extant research has not only confirmed the costly nature of supply chain disruptions but has also contributed relevant insights on such related issues as supply chain risks, vulnerability, resilience, and continuity. In this conceptual note, we focus on a relatively unexplored issue, asking and answering the question of how and why one supply chain disruption would be more severe than another. In doing so, we argue, de facto, that supply chain disruptions are unavoidable and, as a consequence, that all supply chains are inherently risky. Employing a multiple‐method, multiple‐source empirical research design, we derive novel insights, presented as six propositions that relate the severity of supply chain disruptions (i) to the three supply chain design characteristics of density, complexity, and node criticality and (ii) to the two supply chain mitigation capabilities of recovery and warning. These findings not only augment existing knowledge related to supply chain risk, vulnerability, resilience, and business continuity planning but also call into question the wisdom of pursuing such practices as supply base reduction, global sourcing, and sourcing from supply clusters.  相似文献   
995.
RFID technology provides in‐depth, real‐time visibility into the status of assets throughout the supply chain. However, the deployment of RFID technology may have collateral value in the high‐quality data generated by these assets. This study explores the potential value of RFID data for tactical and strategic purposes and the redesign of processes within supply chain through the deployment of simulation modeling and analysis. We present a simulation study conducted at a regional hospital for which data related to trauma patient movement was collected with an RFID‐based system. We find that not only does this data serve as the basis for successful simulation modeling, but that RFID technology may address several data‐related challenges previously identified in the simulation literature.  相似文献   
996.
Reforms known collectively as the new public management (NPM) are sweeping governments worldwide. For a movement espousing customer-based service orientations, there is a curious paucity of research on citizens' attitudes toward these reforms. We know little about how citizens feel about them, how they arrive at their conclusions, and how durable their attitudes are likely to be. Using citizen attitudes culled from the 1987--1992 British General Election Panel Survey, we apply multiple regression analysis to begin exploring these issues in one critical area of NPM reform: privatization of state-owned enterprises. We find that the overall predictive power of the five theoretical perspectives culled from public opinion research and operationalized in our model is quite respectable, but that evaluations are too complex for any single explanation of public opinion formation to capture. We also find that British attitudes toward privatization were most associated with cue-taking from leaders and parties, ideological moorings associated with individualism, and income. From these findings we offer a set of hypotheses suitable for testing in future research—most especially, a disparate impact hypothesis—that have important implications for practice and theory-building regarding public opinion and market-based administrative reforms worldwide.  相似文献   
997.
Several epidemiological studies have found a weak, but consistent association between lung cancer in nonsmokers and exposure to environmental tobacco smoke (ETS). In addition, a purported link between such exposure and coronary heart disease (CHD) has been of major concern. Although it is biologically plausible that ETS has a contributory role in the induction of lung cancer in nonsmoking individuals, dose-response extrapolation-supported by the more solid database for active smokers-gives an additional risk for lung cancer risk that is more than one order of magnitude lower than that indicated by major positive epidemiological studies. The discrepancy between available epidemiological data and dosimetric estimates seems, to a major part, to reflect certain systematic biases in the former that are difficult to control by statistical analysis when dealing with risks of such low magnitudes. These include, most importantly, misclassification of smoking status, followed by inappropriate selection of controls, as well as certain confounding factors mainly related to lifestyle, and possibly also hereditary disposition. A significant part of an association between lung cancer and exposure to ETS would disappear, if, on the average, 1 patient out of 20 nonsmoking cases had failed to tell the interviewer that he had, in fact, recently stopped smoking. In the large International Agency for Research on Cancer (IARC) multicenter study even lower misclassification rates would abolish the weak, statistically nonsignificant associations that were found. In the former study an apparent significant protective effect from exposure to ETS in childhood with respect to lung cancer later in life was reported, a most surprising finding. The fact that the mutation spectrum of the p53 tumor suppressor gene in lung tumors of ETS-exposed nonsmokers generally differs from that found in tumors of active smokers lends additional support to the notion that the majority of tumors found in ETS-exposed nonsmokers have nothing to do with tobacco smoke. The one-sided preoccupation with ETS as a causative factor of lung cancer in nonsmokers may seriously hinder the elucidation of the multifactorial etiology of these tumors. Due to the high prevalence of cardiovascular disease in the population, even a modest causal association with ETS would, if valid, constitute a serious public health problem. By pooling data from 20 published studies on ETS and heart disease, some of which reported higher risks than is known to be caused by active smoking, a statistically significant association with spousal smoking is obtained. However, in most of these studies, many of the most common confounding risk factors were ignored and there appears to be insufficient evidence to support an association between exposure to ETS and CHD. Further, it seems highly improbable that exposure to a concentration of tobacco smoke at a level that is generally much less than 1% of that inhaled by a smoker could result in an excess risk for CHD that-as has been claimed-is some 30% to 50% of that found in active smokers. There are certainly valid reasons to limit exposure to ETS as well as to other air pollutants in places such as offices and homes in order to improve indoor air quality. This goal can be achieved, however, without the introduction of an extremist legislation based on a negligible risk of lung cancer as well as an unsupported and highly hypothetical risk for CHD.  相似文献   
998.
999.
Transshipment, the sharing of inventory among parties at the same echelon level of a supply chain, can be used to reduce costs. The effectiveness of transshipment is in part determined by the configuration of the transshipment network. We introduce chain configurations in transshipment settings, where every party is linked in one connected loop. Under simplifying assumptions we show analytically that the chain configuration is superior to configurations suggested in the literature. In addition, we demonstrate the efficiency and robustness of chain configurations for more general scenarios and provide managerial insights regarding preferred configurations for different problem parameters.  相似文献   
1000.
This paper uses a structural model to understand, predict, and evaluate the impact of an exogenous microcredit intervention program, the Thai Million Baht Village Fund program. We model household decisions in the face of borrowing constraints, income uncertainty, and high‐yield indivisible investment opportunities. After estimation of parameters using preprogram data, we evaluate the model's ability to predict and interpret the impact of the village fund intervention. Simulations from the model mirror the data in yielding a greater increase in consumption than credit, which is interpreted as evidence of credit constraints. A cost–benefit analysis using the model indicates that some households value the program much more than its per household cost, but overall the program costs 30 percent more than the sum of these benefits.  相似文献   
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