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81.
Introduccion     
Resumen

El miedo, como una de las consecuencias de la situación sociopolítica de Argentina en los últimos años, ha afectado, y sigue afectando, a la mayor parte de los miembros de esa sociedad, presentando características diferentes según el periodo considerado, es decir, dictadura, transición a la democracia o gobierno democrático concreto. Se discuten sus implicaciones para la sociedad y se sugieren algunas formas de afrontarlo.  相似文献   
82.
Most real‐life decisions are made with less than perfect information and there is often some opportunity to acquire additional information to increase the quality of the decision. In this article, we define and study the sequential information acquisition process of a rational decision maker (DM) when allowed to acquire any finite amount of information from a set of products defined by vectors of characteristics. The information acquisition process of the DM depends both on the values of the characteristics observed previously and the number and potential realizations of the remaining characteristics. Each time an observation is acquired, the DM modifies the probability of improving upon the products already observed with the number of observations available. We construct two real‐valued functions whose crossing points determine the decision of how to allocate each available piece of information. We provide several numerical simulations to illustrate the information acquisition incentives defining the behavior of the DM. Applications to knowledge management and decision support systems follow immediately from our results, particularly when considering the introduction and acceptance of new technological products and when formalizing online search environments.  相似文献   
83.
84.
On beta regression residuals   总被引:1,自引:0,他引:1  
We propose two new residuals for the class of beta regression models, and numerically evaluate their behaviour relative to the residuals proposed by Ferrari and Cribari-Neto. Monte Carlo simulation results and empirical applications using real and simulated data are provided. The results favour one of the residuals we propose.  相似文献   
85.
Certificates, credentials, and degrees offered through institutions of higher education allow youth development professionals to acquire educational experiences that are recognized in a formal manner.  相似文献   
86.
The lot-sizing problem in capacitated multi-stage systems with a serial product structure is addressed. This is a complex optimization problem that is part of the decision set in material requirements planning (MRP) systems. The mathematical model that describes the problem uses the concept of echelon stock and includes lead times. Setup times are taken into account, which implies that the problem of finding a feasible solution is NP-Complete. This paper proposes a heuristic method that provides a production plan in order to minimize inventory, production, and setup costs. The heuristic starts from a solution for the uncapacitated problem, which is given by the sequential application of the Wagner-Whitin algorithm. Feasibility is then attempted by shifting production amounts between periods. Computational tests conducted in 1,800 instances with up to 40 components and 18 periods have shown that feasible solutions were obtained in 83.7% of the instances. For the infeasible instances, on average, the heuristic is able to find solutions with very low capacity excess. The solutions' quality is evaluated through a lower bound provided by Lagrangean relaxation and on average the gap is less than 10%.  相似文献   
87.
Although new transmuted distributions have been widely proposed in the last few years, it is rarely to find those class of models applied in survival analysis in the presence of censored lifetimes. In this context, we are concerned in applying the transmuted log-logistic model in the study of discharge times of patients treated with the Linezolid drug. For model fitting, we use and compare different profile likelihood methods. Analysis of residuals and influence are also presented. All results are validated in a simulation study by considering the bootstrap techniques.  相似文献   
88.
Low rates of female labor force participation (LFP) have been linked to the absence of childcare policies. This article examines the degree to which extending the school day by 3.5 hours in elementary schools, a large implicit childcare subsidy, affects LFP, the number of weekly hours worked, and the monthly earnings of females with elementary‐school‐age children. To do so, we exploit within‐individual variation in access to full‐time schools and a rotating panel of households that contains 12 years of individual‐level data on labor outcomes and sociodemographic characteristics. Results from long‐difference models show that extending the school day increases mothers' labor supply, increasing LFP by 5.5 percentage points and the number of weekly hours worked by 1.8. Moreover, these increases are accompanied by a raise in monthly earnings. (JEL I25, J13, J22)  相似文献   
89.
The aim of the study was to obtain anthropometric data of adult wheelchair users at Mexico. This study count with 108 disabled people (56 men and 52 women) using the wheelchair and having the upper extremities sufficiently efficient to perform professional activities. The subjects were aged 18-60. From the measurements obtained, it can be said that in each of these measures was observed that men have larger dimensions than women, except for body depth, in which women had a slightly greater difference. When comparing the data in this study against other studies it shows that there is a significant difference between the averages of these studies. Similar results were obtained when comparing our data against data of standard population. Anthropometric data obtained through this study appear to be the only of this kind in Mexico and showed significant differences between measures of disabled persons and standard persons. the use of these data may be helpful for the proper design of workstations designed for use by adults who use.  相似文献   
90.
Due to the lack of anthropometric information in northwest Mexico, we did an anthropometric study that represents the population physical characteristics and that is reliable for the design or redesign of workstations. The study was divided in two phases. The first one was the anthropometric study of 2900 automotive industry workers in northwest of Mexico. The study includes 40 body dimensions of 2345 males and 555 females personalized to be used in future researches. Second phase includes compared anthropometric characteristics of population reported in four Mexican studies and a Colombian study against the current study. Benefits of this project are: a reliable database of anthropometric characteristic of automotive industry population for workstations design or redesign that match with the users, increase product quality and reduce economic, medical and union complains.  相似文献   
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