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21.
A.R. Montazemi  K.M. Gupta 《Omega》1997,25(6):643-658
The objective of this study was to determine the impact of task information (TI) provided by an interface agent during the idea evaluation and integration step of the problem formulation stage of the problem solving process. The effectiveness assessment was based on solving diagnostic decision problems in the domain of complex industrial machinery. Ten domain experts participated in this study. Decision support was provided by a case-based reasoning system. Findings suggest that TI provided by the interface agent had no effect on the decision maker's performance, nor on the associated cognitive effort. However, a verbal protocol analysis revealed that the ten subjects used the interface agent to verify their decision processes. The results and their implications are discussed with respect to current findings in the area of decision support systems.  相似文献   
22.
This article employs Agent-Based Computational Economics (ACE) to investigate whether, and under what conditions, trust is viable in markets. The emergence and breakdown of trust is modeled in a context of multiple buyers and suppliers. Agents develop trust in a partner as a function of observed loyalty. They select partners on the basis of their trust in the partner and potential profit, with adaptive weights. On the basis of realized profits, they adapt the weight they attach to trust relative to profitability, and their own trustworthiness, modeled as a threshold of defection. Trust and loyalty turn out to be viable under fairly general conditions.  相似文献   
23.
自组织建模方法和GDP增长模型研究   总被引:9,自引:3,他引:9  
经济系统的复杂性决定了经济变动及影响因素解释的困难性。本文阐述了一种经济系统复杂性研究的有效方法-自组织建模方法,同时应用此方法建立一个解释我国GDP增长的自组织模型,分析影响我国经济增长的主要因素,并在此基础上提出相应的对策思路。  相似文献   
24.
在食品安全威胁下,农户重新定义了“为自家生产”和“为市场生产”的差别化生产行为。基于经济理性行为假设认为农户存在以确保自家食品安全为动机的生存理性。根据在5省区收集的827份农村入户调研数据,对农户差别化生产行为进行具体分析,描述了差别化生产行为总体特征,并测量农户食品安全自我保护意识、威胁感知程度和信息渠道等因素。运用Probit模型验证了命题:以食品安全自我保护意识为特征的生存理性,支配了农户为确保自家消费安全而进行的差别化生产。  相似文献   
25.
ProblemWomen commonly experience emotional distress following miscarriage but do not receive the support they need from healthcare providers.BackgroundMiscarriage can result in psychological morbidity; however, appropriate support at the time of a miscarriage can lead to better psychological outcomes. Early Pregnancy Assessment Services (EPASs) are dedicated outpatient services considered the “gold standard” for miscarriage care. Little is known about the psychosocial support EPASs provide in Australia.AimsThe aim of this study was to explore the provision of psychosocial support in Australian EPASs.MethodsSemi-structured interviews were conducted with 29 purposively sampled key-informants from 13 EPASs. Interviews were audio-recorded, transcribed, and thematically analysed.FindingsConsiderable variation was found in how EPASs functioned and their provision of psychosocial support. Many services were co-located with antenatal services, run by doctors with limited experience and most did not offer any psychosocial training to staff specific to EPAS. Referrals for additional support were generally not offered for first trimester miscarriages, and follow-up typically focused on physical management rather than emotional wellbeing. All EPAS staff demonstrated a strong commitment to providing best possible care to women within their own clinical setting and acknowledged the need for improved psychosocial support.ConclusionThis study provides the first exploration of Australian EPASs’ provision of psychosocial support. It has shown that while health care professionals working in EPASs are dedicated to providing the best possible care to women within their clinical setting, psychosocial support is very limited and could be improved.  相似文献   
26.
The evaluation of hazards from complex, large scale, technologically advanced systems often requires the construction of computer implemented mathematical models. These models are used to evaluate the safety of the systems and to evaluate the consequences of modifications to the systems. These evaluations, however, are normally surrounded by significant uncertainties related to the uncertainty inherent in natural phenomena such as the weather and those related to uncertainties in the parameters and models used in the evaluation.

Another use of these models is to evaluate strategies for improving information used in the modeling process itself. While sensitivity analysis is useful in defining variables in the model that are important, uncertainty analysis provides a tool for assessing the importance of uncertainty about these variables. A third complementary technique, is decision analysis. It provides a methodology for explicitly evaluating and ranking potential improvements to the model. Its use in the development of information gathering strategies for a nuclear waste repository are discussed in this paper.  相似文献   
27.
The objective of this article is to discuss a needed paradigm shift in disaster risk analysis to emphasize the role of the workforce in managing the recovery of interdependent infrastructure and economic systems. Much of the work that has been done on disaster risk analysis has focused primarily on preparedness and recovery strategies for disrupted infrastructure systems. The reliability of systems such as transportation, electric power, and telecommunications is crucial in sustaining business processes, supply chains, and regional livelihoods, as well as ensuring the availability of vital services in the aftermath of disasters. There has been a growing momentum in recognizing workforce criticality in the aftermath of disasters; nevertheless, significant gaps still remain in modeling, assessing, and managing workforce disruptions and their associated ripple effects to other interdependent systems. The workforce plays a pivotal role in ensuring that a disrupted region continues to function and subsequently recover from the adverse effects of disasters. With this in mind, this article presents a review of recent studies that have underscored the criticality of workforce sectors in formulating synergistic preparedness and recovery policies for interdependent infrastructure and regional economic systems.  相似文献   
28.
环境对量子控制系统的消相干揭示了一个事实,即量子世界里的系统将是一种全新的系统,它是某种开放的、数学的、并且是基于量子逻辑的系统。笔者认为,假如仍然还是立足经典思维,则系统的独立性将难以得到保证,传统的整体论也将变得自相矛盾。只有发展全新的"量子整体论",并在这种新的框架下去审视和建构量子系统,我们才有可能重新获得某种连贯一致的整体论。  相似文献   
29.
Louis Anthony Cox  Jr. 《Risk analysis》2012,32(11):1919-1934
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   
30.
We begin by definition of semi-Markov flow and discussion of its properties. Asymptotic behavior of multi-server and single-server queueing systems is studied under assumption of time-compression or service time growth. The results obtained are used for calculation of large systems reliability. Statistical estimates of parameters involved are also provided.  相似文献   
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