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61.
The aim of this paper is to propose methods of detecting change in the coefficients of a multinomial logistic regression model for categorical time series offline. The alternatives to the null hypothesis of stationarity can be either the hypothesis that it is not true, or that there is a temporary change in the sequence. We use the efficient score vector of the partial likelihood function. This has several advantages. First, the alternative value of the parameter does not have to be estimated; hence, we have a procedure that has a simple structure with only one parameter estimation using all available observations. This is in contrast with the generalized likelihood ratio-based change point tests. The efficient score vector is used in various ways. As a vector, its components correspond to the different components of the multinomial logistic regression model’s parameter vector. Using its quadratic form a test can be defined, where the presence of a change in any or all parameters is tested for. If there are too many parameters one can test for any subset while treating the rest as nuisance parameters. Our motivating example is a DNA sequence of four categories, and our test result shows that in the published data the distribution of the four categories is not stationary. 相似文献
62.
The paper explores the degree to which Indigenous groups perceive that resource management plans they develop are able to help deliver outcomes they seek through formal planning systems. It does this by a case study of practice in Aotearoa New Zealand. Some Indigenous groups are concerned they are being encouraged to devote considerable effort to production of major planning documents for use in interaction with environmental agencies, yet in practice, such plans can appear to have a limited role in bringing about desired change or affecting wider planning processes. The research contributes a New Zealand dimension to this international debate. 相似文献
63.
Neighbourhood planning (NP) as enabled by the 2011 Localism Act in England has precipitated a considerable literature discussing its potential, limitations and likely shortcomings referenced against government rhetoric and the reporting of initial experiences of the process. This paper provides an overview of the current literature on neighbourhood planning and sets out how it has been received and practised across England drawing on empirical evidence. The extent of take-up and the experience of those involved in the first five years of neighbourhood planning is used to consider how community-led planning may be designed and used following operational principles of inclusivity, capacity-building and adding value. 相似文献
64.
园林景观规划设计与地域文化 总被引:1,自引:0,他引:1
地域文化的缺失导致园林景观规划设计及其实施效果呈现雷同的趋势,通过提出规划设计中地域文化的范畴和意义,强调了体现地域文化在规划设计中的重要性。借助三个实际的规划设计案例从宏观角度提出规划概念应与地域自然特点、人文特点等要素有机结合,从而从微观角度提出设计可采用保留、抽取、融合、再现等手法来体现地域文化。此外,在规划设计中运用地域文化应该注意契合性、创新性、烂漫性及可实施性等的几个方面的问题。 相似文献
65.
Chen Li 《统计学通讯:理论与方法》2017,46(2):874-891
This paper further studies monotone aging properties of the multivariate random lifetime. We revise the sufficient condition for the negative monotone aging property in terms of the multivariate usual stochastic order in Theorem 3.3 of Rezapour et al. (2013) and derive the condition sufficient to the multivariate monotone aging properties in terms of the upper orthant order. Also we study the upper orthant order of multivariate residual lifetimes and inactivity times from populations sharing a common Archimedean survival copula and Archimedean survival copula, respectively. Two simple applications in multivariate stress-strength and frailty models are presented as well. 相似文献
66.
《Omega》2014
In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing. 相似文献
67.
《Omega》2017
Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper. 相似文献
68.
Deborah J. Monahan Katie Kietzmann Carrie Jefferson Smith Vernon L. Greene 《Journal of intergenerational relationships》2017,15(4):315-325
Kinship caregivers are a child-care resource for families experiencing stress or temporary parenting due to illness, incarceration, or death of a parent. This article examines whether and how felt caregiver burden influences the reported propensity of caregivers to want to adopt the children in their care. Kinship caregivers who were enrolled in KinNET completed the survey (N = 102) and the data were entered anonymously into SPSS for analysis. Their mean age was 57.51 years (SD = 10.13), 95% were female (SD = .19), and two-thirds were non-white (SD = .73). Using “likelihood of adopting the child in my care,” as the outcome variable in the linear regression analysis, caregiver’s age, monthly income, and total hours employed were significant predictors. Total pressures, family service needs, and physical problems scales were not statistically significant predictors. The adjusted R square was .439 and significant (.006). Understanding the factors that are predictive of adopting children in kinship care will help programs target services more effectively. Helping kinship caregivers and the children in their care is also important in promoting their health and social well-being. 相似文献
69.
Extreme and catastrophic events pose challenges for normative models of risk management decision making. They invite development of new methods and principles to complement existing normative decision and risk analysis. Because such events are rare, it is difficult to learn about them from experience. They can prompt both too little concern before the fact, and too much after. Emotionally charged and vivid outcomes promote probability neglect and distort risk perceptions. Aversion to acting on uncertain probabilities saps precautionary action; moral hazard distorts incentives to take care; imperfect learning and social adaptation (e.g., herd‐following, group‐think) complicate forecasting and coordination of individual behaviors and undermine prediction, preparation, and insurance of catastrophic events. Such difficulties raise substantial challenges for normative decision theories prescribing how catastrophe risks should be managed. This article summarizes challenges for catastrophic hazards with uncertain or unpredictable frequencies and severities, hard‐to‐envision and incompletely described decision alternatives and consequences, and individual responses that influence each other. Conceptual models and examples clarify where and why new methods are needed to complement traditional normative decision theories for individuals and groups. For example, prospective and retrospective preferences for risk management alternatives may conflict; procedures for combining individual beliefs or preferences can produce collective decisions that no one favors; and individual choices or behaviors in preparing for possible disasters may have no equilibrium. Recent ideas for building “disaster‐resilient” communities can complement traditional normative decision theories, helping to meet the practical need for better ways to manage risks of extreme and catastrophic events. 相似文献
70.
Potential of decentralized wastewater management for urban development: Case of Bangkok 总被引:1,自引:0,他引:1
Decentralized wastewater management (DWWM) has recently gained much attention in wastewater management (WWM) due to its build-as-you-go principal. Rapid urban development and the widespread impact of wastewater require sustainable ways to test the DWWM approach. This paper aims to examine and discuss the potential of Bangkok’s current WWM approaches for urban development, focusing on decentralized management approaches. General WWM approaches were examined using case study research methods. Three WWM cases were selected for detailed investigation. Residential wastewater user surveys and expert interviews were used to support system performance findings of service providers and recipients, as well as to draw lessons learned. Results show that DWWM is economically and technically efficient, demonstrating potential for sustainable urban development (SUD) in the study area. The competitive cost found is a result of less sewer line, simple technology, and limited additional costs, while the high efficiency is a result of good operation and maintenance. Also the reclaimed water has been used for landscape irrigation of the urban greenery. Sustainability of the system lies in social value of public amenity it provides, and the urban planning implication that it could be an option for smart growth. The results also show that even in an inner urban area DWWM does not conflict with any SUD considerations. Thus, the study recommends using DWWM for new development within both public and private properties based on Bangkok’s case as part of long-term urban development. 相似文献