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111.
Recent studies have shown the high prevalence of youth gambling behavior. In particular, lottery ticket purchases among children and adolescents appear to be a highly preferred activity. Despite this fact, most research has focused on the underlying erroneous cognitions used by adults when selecting lottery tickets. This study examines the cognitive perceptions of children while engaged in selecting 6/49 lottery tickets. One hundred sixty-seven children (61 females; 106 males) from grades 3, 5, and 7 were asked to rank pre-selected 6/49 lottery tickets which were classified into a) long series, b) specific patterns, c) non equilibrated numbers, or d) perceived random selections. Children verbalized their rationale for selecting each ticket and were permitted to change the numbers on the lottery tickets they liked least in order to make them to more likely to be the winning ticket. Findings, in general, revealed small developmental differences in the types of underlying cognitive heuristics used by the children. The use of cognitive heuristics underlying the concept of randomness and the use of significant and meaningful numbers was observed to increase as children got older. Children between 9 and 11 were found to have employed the cluster heuristic more frequently than older children, ages 12–13. The results are interpreted in terms of the cognitive developmental changes in children's perceptions and the potential implication for gambling prevention programs are provided.  相似文献   
112.
V.K. Gupta  J.G. Chen  M.B. Murtaza 《Omega》1997,25(6):715-727
In several key functional areas of contemporary engineering and management science, neural networks have steadily been gaining recognition as robust and reliable tools for classification problems. This paper describes a new application of the learning vector quantization neural network: the classification of the degree of modularization appropriate for the construction of an industrial facility. This neural network uses variables related to plant location, labor issues, organizational issues, plant characteristics, project risks, and environmental issues as inputs to perform the classification. The neural network training and performance evaluation is also discussed.  相似文献   
113.
Time series analysis of out-patients at Urban Health Centre, Suraj Kund, Meerut, was done using the out-patient attendance of last five years, with the aim to find out the values to help in coping up with the problem of health administration and management. The least square method and ratio-to-trend method were adopted for calculating the secular trend and seasonal variations respectively. There was an increasing trend in out-patients attendance indicating the increasing popularity of the Urban Health Centre. It was found that in second and third quarter of the year the out-patient attendance increased extraordinarily due to various reasons. The two more aspects of time series, i.e. cyclical trend and irregular flactuation could not be analysed due to their insignificant impact over the health management system.  相似文献   
114.
Heavy equipment overhaul facilities such as aircraft service centers and railroad yards face the challenge of minimizing the makespan for a set of preventive maintenance (PM) tasks, requiring single or multiple skills, within workforce availability constraints. In this paper, we examine the utility of evolution strategies to this problem. Comparison of the computational efforts of evolution strategies with exhaustive enumeration to reach optimal solutions for 60 small problems illustrates the ability of evolution strategies to yield optimal solutions increasingly efficiently with increasing problem size. A set of 852 large‐scale problems was solved using evolution strategies to examine the effects of task‐related problem characteristics, workforce‐related variables, and evolution strategies population size (μ) on CPU time. The results empirically supported practical utility of evolution strategies to solve large‐scale, complex preventive maintenance problems involving single‐ and multiple‐skilled workforce. Finally, comparison of evolution strategies and simulated annealing for the 852 experiments indicated much faster convergence to optimality with evolution strategies.  相似文献   
115.
It has been argued in the literature that business strategy and manufacturing flexibility independently affect the performance of an organization. However, no empirical examination of the interrelationship among these three constructs has been performed. In this paper, based on a field study of 269 firms in the manufacturing industry, the identified constructs have been used to test a theoretical model using path analysis techniques. Our results indicate that business strategy contributes both directly and indirectly to organizational performance. The findings provide evidence of direct effects of (i) business strategy on manufacturing flexibility and (ii) manufacturing flexibility on organizational performance.  相似文献   
116.
Political survey data for nine West European countries show that women have become increasingly left‐wing compared to men, and that this trend is positively correlated with the rise of nonmarriage in these countries. This pattern is mirrored in German longitudinal data (GSOEP), where transitions out of marriage make women, but not men, significantly more left‐leaning. Analysis of public spending data for high‐income OECD countries (1980–1998) suggests that the political impact of nonmarriage extends to the allocation of State resources with increases in nonmarriage first reducing, and then increasing, State redistribution towards children. (JEL: H31, H42, J12, J13)  相似文献   
117.
118.
In this article, we consider the multiple step stress model based on the cumulative exposure model assumption. Here, it is assumed that for a given stress level, the lifetime of the experimental units follows exponential distribution and the expected lifetime decreases as the stress level increases. We mainly focus on the order restricted inference of the unknown parameters of the lifetime distributions. First we consider the order restricted maximum likelihood estimators (MLEs) of the model parameters. It is well known that the order restricted MLEs cannot be obtained in explicit forms. We propose an algorithm that stops in finite number of steps and it provides the MLEs. We further consider the Bayes estimates and the associated credible intervals under the squared error loss function. Due to the absence of explicit form of the Bayes estimates, we propose to use the importance sampling technique to compute Bayes estimates. We provide an extensive simulation study in case of three stress levels mainly to see the performance of the proposed methods. Finally the analysis of one real data set has been provided for illustrative purposes.  相似文献   
119.
在戈尔斯坦、查隆和比尔最近发表的论文--<高海拔缺氧、文化和人类生育力或生殖能力的比较研究>(载<美国人类学家>85:28-49,1983)中,作者试图把文化当作解释喜马拉雅山区居民人口差异问题的惟一因素,完全排除了缺氧的影响,同时他们还对别人过去发表的用缺氧进行解释的相关材料(魏兹以及其他人1978;本格汉和塞奇勒1980;古朴塔1980)提出批评.  相似文献   
120.
One of the most efficient ways to manage the information systems function is to introduce steering committees. It has been suggested that one of the foremost benefits of a steering committee is that it can improve the information systems planning efforts of an organization. However, there is very little empirical evidence in the literature that deals with how such committees affect planning. This study investigates the impact of steering committees on three phases of information systems planning: strategic planning, systems planning, and implementation of planning. The greatest impact of steering committees appears to be the strategic planning phase, while a lesser effect is observed in the systems planning and implementation of planning phases.  相似文献   
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