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981.
Personal Protective Equipment (PPE) is considered the last preferred solution to an Occupational Safety Health (OSH) system. Brazilian OSH legislation assumes and requires PPE usage to neutralize the possibility of pesticide contamination. This study examines the inadequacy of the PPE used in a tomato crop, particularly from the standpoint of thermal comfort. This study made observations regarding heart rate and body temperature in a controlled environment using a treadmill (with and without PPE) of 12 volunteers; and during the process of rural labor (at rest and in normal work routine) of 2 actual rural workers. Comparing the results of the treadmill test (with and without PPE) which tried to reproduce the same level of effort and environmental conditions of the actual rural work, this study demonstrated that PPE makes thermoregulation harder and tympanic temperature reaches higher values with the same level of effort. Moreover, body temperature increases quickly: with PPE it took 15 minutes to raise 1°C in body temperature, compared to 40 minutes without PPE. The results of this study indicated that the use inadequate PPE might pose thermoregulation risk to rural workers.  相似文献   
982.
There are several forest operations involved in Eucalyptus timber harvesting. This study was carried out during brush-cutting; tree felling, bucking, delimbing, piling and manual extraction operations, with the following objectives: a) analyzing, ergonomically, two systems of brush-cutting: one manual and the other semi-mechanized, using two different machines; b) ergonomically evaluating three different brands of pruner machines used in delimbing felled trees. c) determining the feasible target of productivity as a function of ergonomic factors relevant to establish the time of resting pauses for workers in manual and semi-mechanized timber harvesting systems in mountainous terrain. Brush-cutting, either manual or semimechanized, is an activity carried out prior to timber harvesting. It is usually a hard work, with low productivity when compared with mechanized systems. Pruner machines have been used by forest companies, due to the great possibilities to improve productivity, quality and the health of workers. Ergonomics is a discipline that promotes the adequacy of work to the physical and mental characteristics of human beings, seeking to design production systems and products considering relevant aspects, including social, organizational and environmental factors. Companies should consider the ergonomic factor in the determination of daily worker production targets.  相似文献   
983.
The aim is to identify ergonomic intervention methods used for including people with disabilities (PD) in the Brazilian labor market, with emphasis on discussion of methods to analyze the fit between the worker and the workplace. Methods to evaluate the fit of the worker to the workplace identify the capabilities and limitations of PDs and the demands of work, combining these data, and comparing them, in order to obtain a detailed analysis of the fit were drawn from national and international publications. These show that the use of specific methods for PDs and others focused on the general population. Mutatis mutandis, there is a need for complementary tools to address this segment. Thus, for the Brazilian scenario, it is essential to develop specific methodological tools to assess the capabilities of a PD so that they may better interact with their job.  相似文献   
984.
This paper presents an assessment with simulated activities with the aim of analyzing the perception of ease / difficulty of the use of faucets (taps) handles by 180 Brazilian adults. Five different handles faucets were activated for subsequent collection of perceptual data. The procedures were based on main recommendations for biomedical ethics and human research. The results indicate that handles with levers are significantly (p ≤ 0.05) easier to use. The most difficult are characterized by not having support points for the rotation (levers) or more points of pressure concentration in the hand.  相似文献   
985.
This work is based on the ergonomic approach and the principles of universal design, with the aim of establishing the cognitive design features that interfaces must comply, for older adults achieve a good performance during their interaction with technological aids. Describes the analysis of exploratory experiences with a group of 17 older adults was aimed first to establish the main barriers to implementation that arise during these activities, and secondly to set the variables to be addressed and the procedure required to develop depth study, where the relationship establish between the quality of the stimuli and the level of performance achieved in the implementation of older adults with interfaces, observing each of the cognitive functions that promote independence, attention, motivation, memory these processes. The study in depth, looking for describe gaps and mismatches encountered during execution, which hamper the harmonious interaction processes through participatory methodological approach that allows to specify requirements for the creation of stimulating interfaces for cognitive skills and committed with the levels of autonomy of the elderly.  相似文献   
986.
987.
This work was undertaken in France at the request of a local fire and rescue school in order to conduct an analysis of driving two types of heavy rescue vehicle with a view to improving training. This study took place in a context of specialisation: the drivers of these vehicles will henceforth only perform this type of task. Consequently, specific training has been designed in advance. Our study concerns the improvement of this training, taking account of the particularities of driving these vehicles in emergency situations typical to the profession of fire-fighters. The results stress first that driving of rescue vehicles in emergency situations is a multidimensional collective activity. Driving strategies identified share certain common objectives: "optimising trajectories", warn other road users, anticipate their behaviour and leave room for manoeuvre to counter and react to any unexpected behaviour. They include risks management for the potential victims of the incident and the risk of accidents during the journey. These initial results help identify certain recommendations for the training courses dealing with driving vehicles in emergency situations. They also provide a warning concerning the possible consequences of driver specialisation.  相似文献   
988.
In the areas of design, especially in architectural design, collaboration has become an important challenge. The specialization of skills increase, work teams are more and more extensive and the geographic distance between them increases too. The economic and ecological stakes related to remote collaboration are an evidence. This context involves the need to support most efficiently possible remote working meetings. We present the Distributed Collaborative Digital Studio (DSDC), a tool designed to recreate, in distant situations, the context of copresence meetings. This shared environment is created in the "invisible computer" approach [11]. The idea is that the tool should disappear from user's consciousness. Indeed, creative design activities require some fluidity in their process. Therefore, any involuntary interruption created by the system can potentially brake creativity. In this perspective, we investigate specifically the "invisibility" of our environment. To do this, we propose a framework for the operationalization of the concept and a methodology to test the system invisibility. This methodology was applied through a case study consisting of a corpus of 12 hours of remote collaborative design sessions with the DSDC. We highlight the learning effects while using our system, conclude on its effectiveness and discuss our methodology.  相似文献   
989.
The main focus of risk management is technical and rational analysis about the operational risks and by those imposed by the occupational environment. In this work one seeks to contribute to the risk perception study and to better comprehend how a group of occupational safety students assesses a set of activities and environmental agents. In this way it was used theory sustained by psychometric paradigm and multivariate analysis tools, mainly multidimensional scaling, generalized Procrustes analysis and facets theory, in order to construct the perceptual map of occupational risks. The results obtained showed that the essential characteristics of risks, which were initially splited in 4 facets were detected and maintained in the perceptual map. It was not possible to reveal the cognitive structure of the group, because the variability of the students was too high. Differences among the risks analyzed could not be detected as well in the perceptual map of the group.  相似文献   
990.
A number of studies to better understand the complex physiological mechanism involved in regulating body weight have been conducted. More specifically, the hormones related to appetite, leptin and ghrelin, and their association to obesity have been a focus of investigation. Circadian patterns of these hormones are a new target of research. The behaviour of these hormones in individuals subject to atypical working times such as shiftwork remains unclear. Shiftwork is characterized by changes in biological rhythms and cumulative circadian phase changes, being associated with high rates of obesity and metabolic syndrome. Truck drivers, who work irregular shifts, frequently present a high prevalence of obesity, which might be associated with work-related factors and/or lifestyle. In this context, the aim of this paper was to discuss the relationship of body mass index, appetite-related hormones and sleep characteristics in truck drivers who work irregular shifts compared with day workers.  相似文献   
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