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141.
This article is the result of a case study on ergonomic work analysis carried out in an urban bus company located in Ilha do Governador, Rio de Janeiro. The methodology used in this work follows the French-tradition Ergonomic Analysis of the Work (EWA) combined with the best tradition from anglo-saxon ergonomic work analysis. The situated diagnosis was performed to provide relevant information about the work conditions of a bus driver.  相似文献   
142.
The number of occupational diseases in Mexico is alarming and clearly it is important to do studies with the purpose of improving the design of workstations. The objective of this research is to determine the maximum force levels in different positions of shoulder and elbow. An experiment was conducted with 16 subjects between 18 and 28 years old: 8 male and 8 female. We considered 16 different positions, working with the right and left arm to perform the tasks of pull and push. The tasks consisted of pushing or pulling a dynamometer for a period of 3 seconds as hard as possible. The results were presented in tables. The tables show the mean, standard deviation and range of force levels in different positions.  相似文献   
143.
The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of two public Middle School students from Paraíba (Brazil). The target population included 8th grade groups involving 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck and about 90% of the students presented postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints.  相似文献   
144.
This article examines the influence of the business cycle on expenditures of three major types of legalized gambling activities: Casino gambling, lottery, and pari-mutuel wagering. Empirical results are obtained using monthly aggregated US per capita consumption time series for the period 1959.01–2010.08. Among the three gambling activities only lottery consumption appears to be recession-proof. This series is characterized by a vast and solid growth that exceeds the growth in income and the growth in other gambling sectors. Casino gambling expenditures show a positive growth during expansions and no growth during recessions. Hence, the loss in income during recessions affects casino gambling. However, income shocks which are not directly related to the business cycle do not influence casino gambling expenditures. Pari-mutuel wagering displays an overall negative trend and its average growth rate is smaller than the growth in income, especially during recessions. The findings of this article provide important implications for the gambling industry and for local governments.  相似文献   
145.
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   
146.
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   
147.
Into dangerous and complex systems with high degree of interactivity between its components, the variability is present at all time, demanding a high degree of control of its operation. Maintaining or recovering the normality, when the system is under some stress (instability) is a function of Resilience. To cope with prevention, forecast, recovery and with memory of experiences from learned lessons requires some features from the companies. This paper purposes a structure that enables the Total Resilience of a system production that defines the assignments for Workers, Designers and Management Team, according to its features and possibilities. During one year and a half developing studies on ergonomics area of a Brazilian Oil Refinery, several situations were observed and studied using Work Ergonomic Analysis. These situations show actions and strategies that workers use to maintain the system stability. Furthermore, they revealed the importance that these actions are stored in a database of learned lessons from the Company. The research resulted in a broad scheme. It places each of these groups in the process of Total Resilience. It also shows the human like a center of actions that ensure the continuity of the system, main element at Resilience (Anthropocentric View).  相似文献   
148.
Previous studies suggest significant differences between navigating virtual environments in a life-like walking manner (i.e., using treadmills or walk-in-place techniques) and virtual navigation (i.e., flying while really standing). The latter option, which usually involves hand-centric devices (e.g., joysticks), is the most common in Virtual Reality-based studies, mostly due to low costs, less space and technology demands. However, recently, new interaction devices, originally conceived for videogames have become available offering interesting potentialities for research. This study aimed to explore the potentialities of the Nintendo Wii Balance Board as a navigation interface in a Virtual Environment presented in an immersive Virtual Reality system. Comparing participants' performance while engaged in a simulated emergency egress allows determining the adequacy of such alternative navigation interface on the basis of empirical results. Forty university students participated in this study. Results show that participants were more efficient when performing navigation tasks using the Joystick than with the Balance Board. However there were no significantly differences in the behavioral compliance with exit signs. Therefore, this study suggests that, at least for tasks similar to the studied, the Balance Board have good potentiality to be used as a navigation interface for Virtual Reality systems.  相似文献   
149.
Upper extremity musculoskeletal symptoms and disorders are common in the working population. The economic and social impact of such disorders is considerable. Long-time, dynamic repetitive exposure of the hand-arm system during manual handling operations (MHO) alone or in combination with static and postural effort are recognised as causes of musculoskeletal symptoms and disorders. The assessment of these manual work tasks is crucial to estimate health risks of exposed employees. For these work tasks, a new method for the assessment of the working conditions was developed and a validation study was performed. The results suggest satisfying criterion validity and moderate objectivity of the KIM-MHO draft 2007. The method was modified and evaluated again. It is planned to release a new version of KIM-MHO in spring 2012.  相似文献   
150.
The objective of the study was to evaluate the occurrence of Burnout Syndrome in 100 teachers of six public high schools and its correlation with working conditions in a southeast city of Brazil. Characterization of the sample occurred after application of a socio-demographic questionnaire. Evaluation of the working conditions was done by means of an Ergonomic Working Analysis. The presence of Burnout Syndrome was evaluated by means of the Maslach Burnout Inventory. The sample presented the predominance of women, with an average age of 40.4 and the majority married with children. Roughly 50% had less than 10 years of service, and more than half of the teachers taught more than 18 classes per week. Hoarseness after work was principally reported among women, which required many days off for health treatment. Environmental conditions reflect inadequacy in relation to noise, light, humidity and temperature. Presence of pain in the upper limbs was especially high among women. Risk of musculoskeletal disorders in the upper limbs predominated as moderately important to significant. We also identified an average distance walked by teachers of 1.5 Km and an average of 4.2 Kg of school supplies carried between classes. The Burnout Syndrome presented a high score for depersonalization principally among men, but it has association with both sexes. Emotional exhaustion correlates with noise, depersonalization, and personal fulfillment, in addition to the high number of weekly lessons. It can be concluded that Burnout syndrome is present among teachers, principally in terms of depersonalization, deserving the attention of government officials and the schools, as well as the teachers themselves.  相似文献   
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