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891.
Increasingly many firms have started to implement programs intended to improve the workers' health and the psychosocial work‐environment, as well as other attributes of labor quality. Motivated by the need for evaluating to what extent the programs affect a firm's productivity performance, this study discusses a model for analyzing the contribution of labor quality attributes toward firm productivity. To assess the contribution from the labor quality attributes, we model firm productivity as the outcome of two separate processes within a firm: the physical production process and the labor quality process. Firm productivity is measured by a Malmquist‐like productivity index and is computed by Data Envelopment Analysis. Based on bootstrap methods we analyze potential statistical bias and provide bias‐corrected productivity estimates. The labor quality attributes are first modeled at an individual worker level as latent variables using Item Response Theory, and then aggregated to a firm‐level. The model is empirically validated using data from three manufacturing plants that participated in a coordinated worksite health promotion program. Over a 4‐year period (2000–2003), we observed a general improvement in efficiency of 2–5%, half of which could be attributed to an improvement in workers' health and psychosocial work‐environment. A key benefit with the model is that it is practical, easy to implement, and very fast to compute. The model also constructively contributes to the discourse on sustainability by providing a framework for deriving meaningful metrics and providing tangible measurements on the effect of sustainability‐related issues.  相似文献   
892.
We investigate strategic information sharing in two competing channels. The retailer in a channel can ex post decide whether to share private demand information with his upstream manufacturer after the content of information becomes known. We find that a retailer discloses low demand and withholds high demand to induce lower wholesale prices from his manufacturer. We show that a retailer should share less information when the retail market becomes more competitive, but should disclose more information when his capability to acquire information improves. When a decentralized supply chain competes with an integrated channel, we show that firms in the supply chain benefit from the rival channel's effort to improve information capability, that the incentive for the retailer in the supply chain to improve his information capability increases with the intensity of competition and with the rival channel's information capability, and that the retailer may not want to pursue perfect information acquisition even when doing so is costless. Extensive numerical studies demonstrate that similar results also hold for two decentralized supply chains competing with each other.  相似文献   
893.
The Genesis of this Special Issue came from the Board of the POMS College on Humanitarian Operations and Crisis Management (HO&CM). It was seen as a necessary initiative to define the field and examine research opportunities. This Special Issue shows that humanitarian operations pose challenges for P/OM researchers and practitioners that differ markedly from those of conventional supply chains associated with profitable enterprises. On the basis of the eight articles in this Special Issue, we have described and demonstrated the unique characteristics of the POM/HO&CM interaction. We have also identified those attributes that tend to overlap with conventional aspects of POM. In addition to wanting to be cost effective, the issue of equity fairness is pervasive in humanitarian operations, and so is the need to always base considerations on “last‐mile logistics,” that is, getting aid to those in most need. Research is essential to determine how to train researchers to scout out and map the territory of the real problems. One of the most vexing problems is the lack of robust data in the humanitarian domain which is as richly varied as the types of disasters that can occur.  相似文献   
894.
如何提高人力资源管理水平 ,增强竞争优势是摆在商业银行人力资源管理者面前的一个严峻而重大的课题。本文认为商业银行应重塑人力资源管理理念 ,认清所面临的风险和挑战 ,结合商业银行的实际情况和人力资源国际化的要求 ,建立起充满生机与活力的人力资源管理体制  相似文献   
895.
Summary We performed multiple-generation competition experiments betweenCallosobruchus analis andC. phaseoli with different bean sizes. In each system, we supplied 5 g of mung beans (Vigna radiata) every 10 days. We examined three types of bean conditions: 5 g of large beans, 5 g of small beans, and a mixture of 2.5 g of large and small beans. In small bean condition,C. analis dominatedC. phaseoli in all three replicates andC. phaseoli was extinct by the 260th day. On the contrary,C. phaseoli overcameC. analis within 250 days in large beans in all three replicates. In mixed beans condition the two bruchid species coexisted more than 500 days in two out of the three replicates. Even in the exceptional case, both species coexisted for 460 days. These results were examined in the light of the predictions from short-term larval competition experiments and a game theoretical model by Smith and Lessells (1985). The density and frequency dependent results during larval competition inside a bean was concluded to be a main factor to produce the above long-term competition results.  相似文献   
896.
Summary The effects of egg cannibalism, conditioned medium and the presence of quinone secretions on oviposition rate were studied using single pairs of adults to eliminate any direct crowding effects. Most measurements were made on beetles confined to the surface of the flour medium in plastic towers. Oviposition rate was decreased by about 58% when pairs were transferred from fresh to conditioned medium; lowered about 25% when only quinones were present and the medium was still fresh; and enhanced 35% in dry conditions when beetles were provided with eggs to eat. Both the lowered oviposition rate in confined cultures and egg-eating may be explained by natural selection at the individual level. Cannibalizing eggs boosts a female's oviposition rate. The presence of quinones or conditioned medium indicates high population densities and acts as a signal for ceasing oviposition and dispersing to avoid high egg mortality. In confined populations, this results in population regulation, while in open populations, this strategy is a mechanism to avoid competition. It implies that the resource shortages normally experienced by such organisms are relative, not absolute.  相似文献   
897.
The mathematical model presented here aims to elucidate the essential mechanisms of coexistence of species, especially those of closely related forms, as a result of competition in the same environment. It describes a system where the fate of the competitors or mutants is observed at the initial stage of evolution. The model encompasses both the external variables and the internal state of the competitors, which differ only in one of the metabolic rate constants. Results of simulations, even with the simplified form of the model, show that stable coexistence of closely related forms in a uniform environment is possible. In addition, the model allows the analysis of the limitations on the level of differences and similarities among the competitors for achieving a state of coexistence. The essential mechanisms for the coexistence of closely related competitors are proposed to be the involvement of the metabolic network in allowing the same growth rate of competitors which have different internal states, and the interplay between the internal states of the competitors and the external variables of their environment.  相似文献   
898.
Although project portfolio management has been an active research area over the past 50 years, budget allocation models that consider competition are sparse. Faced with the competition, firms contemplating budget allocation for their project portfolio cannot limit their attention to the returns from their projects' target markets, as is the case for monopoly firms, but must also anticipate the competitive effects on these returns. Assuming firms allocate their budgets between projects offering incremental innovation targeting a mature market and projects offering radical innovation targeting an emerging market, we show that while the monopoly firm bases its budget allocation decision solely on the marginal returns of the markets, competing firms—as they take into account their counterparts' investment decisions—need to also consider the projects' average returns from their respective markets. This drives competing firms into incrementalism: faced with competition, firms invest larger portions of their budgets into projects targeting mature markets. This effect is amplified as the number of competing firms increases and firms allocate an even greater share of their budget into projects targeting a mature market. We further demonstrate the effects that changes to firms' individual budgets, as well as to market characteristics, have on firms' budget allocation decision.  相似文献   
899.
In many real‐life house allocation problems, rents are bounded from above by price ceilings imposed by a government or a local administration. This is known as rent control. Because some price equilibria may be disqualified given such restrictions, this paper proposes an alternative equilibrium concept, called rationing price equilibrium, tailored to capture the specific features of housing markets with rent control. An allocation rule that always selects a rationing price equilibrium is defined, and it is demonstrated to be constrained efficient and (group) non‐manipulable for “almost all” preference profiles. In its bounding cases, the rule reduces to a number of well‐known mechanisms from the matching literature. In this sense, the housing market with rent control investigated in this paper integrates several of the predominant matching models into a more general framework.  相似文献   
900.
培养和提升高职院校教师的胜任力,对推进职业教育教学改革,增强学校的核心竞争力,促进高职院校健康、高效、持续发展具有极其重要的作用,而通过职业技能竞赛的开展,教师参与职业技能训练的指导,对提升教师胜任力的作用是多方面、全方位的。  相似文献   
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