全文获取类型
收费全文 | 24327篇 |
免费 | 466篇 |
国内免费 | 1篇 |
专业分类
管理学 | 2981篇 |
民族学 | 129篇 |
人才学 | 3篇 |
人口学 | 2188篇 |
丛书文集 | 117篇 |
教育普及 | 3篇 |
理论方法论 | 2123篇 |
综合类 | 264篇 |
社会学 | 12103篇 |
统计学 | 4883篇 |
出版年
2023年 | 146篇 |
2022年 | 116篇 |
2021年 | 158篇 |
2020年 | 396篇 |
2019年 | 496篇 |
2018年 | 709篇 |
2017年 | 935篇 |
2016年 | 661篇 |
2015年 | 503篇 |
2014年 | 630篇 |
2013年 | 4641篇 |
2012年 | 861篇 |
2011年 | 682篇 |
2010年 | 566篇 |
2009年 | 463篇 |
2008年 | 532篇 |
2007年 | 517篇 |
2006年 | 516篇 |
2005年 | 486篇 |
2004年 | 397篇 |
2003年 | 394篇 |
2002年 | 414篇 |
2001年 | 578篇 |
2000年 | 520篇 |
1999年 | 516篇 |
1998年 | 358篇 |
1997年 | 310篇 |
1996年 | 389篇 |
1995年 | 369篇 |
1994年 | 388篇 |
1993年 | 363篇 |
1992年 | 400篇 |
1991年 | 394篇 |
1990年 | 405篇 |
1989年 | 353篇 |
1988年 | 377篇 |
1987年 | 319篇 |
1986年 | 294篇 |
1985年 | 334篇 |
1984年 | 341篇 |
1983年 | 266篇 |
1982年 | 233篇 |
1981年 | 189篇 |
1980年 | 197篇 |
1979年 | 223篇 |
1978年 | 189篇 |
1977年 | 164篇 |
1976年 | 136篇 |
1975年 | 144篇 |
1974年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
Van Deun D Verhaert V Willemen T Wuyts J Verbraecken J Exadaktylos V Haex B Vander Sloten J 《Work (Reading, Mass.)》2012,41(Z1):1274-1280
Proper body support plays an import role in the recuperation of our body during sleep. Therefore, this study uses an automatically adapting bedding system that optimises spinal alignment throughout the night by altering the stiffness of eight comfort zones. The aim is to investigate the influence of such a dynamic sleep environment on objective and subjective sleep parameters. The bedding system contains 165 sensors that measure mattress indentation. It also includes eight actuators that control the comfort zones. Based on the measured mattress indentation, body movements and posture changes are detected. Control of spinal alignment is established by fitting personalized human models in the measured indentation. A total of 11 normal sleepers participated in this study. Sleep experiments were performed in a sleep laboratory where subjects slept three nights: a first night for adaptation, a reference night and an active support night (in counterbalanced order). Polysomnographic measurements were recorded during the nights, combined with questionnaires aiming at assessing subjective information. Subjective information on sleep quality, daytime quality and perceived number of awakenings shows significant improvements during the active support (ACS) night. Objective results showed a trend towards increased slow wave sleep. On the other hand, it was noticed that % N1-sleep was significantly increased during ACS night, while % N2-sleep was significantly decreased. No prolonged N1 periods were found during or immediately after steering. 相似文献
952.
Work related musculoskeletal disorders are seen as an indicating parameter of occupational stress among the women workers engaged in tea leaf plucking operation. The hand plucking (no mechanized plucking is practiced in Assam) being a highly repetitive task requires forceful exertions to reach to the distant periphery of the tea bushes and mechanical compression (pressing against hard surfaces). Specifically it aggravates with awkward positions adopted. The current research addresses to minimize the risk factors associated with CTDs and to ascertain the role of ergonomic design development in improving the situation. Women workforce engaged in tea industry in Assam suffer from back, shoulder, arm and finger pains. Workers perform the activity for 440 minutes in the entire shift with one hour lunch break in between in the garden itself. An ergonomic investigation aiming at studying the strain index of plucking operation in tea industry was conducted. While performing the operation workers were found to assume unnatural posture which is static as well as highly dynamic with a load (tea leaf collecting basket up to weight of 30 kg when filled with plucked leaves) at back. With gradual increment of load and pain though the load is released intermittently the strain level found to remain at a high level. The total QEC scores found for plucking activity was 110 out of 138. To improve the situation and to reduce the work related upper limb disorder (WRULD) an ergonomically designed basket was conceived and trial results showed improvements. The newly designed plucking basket fits the back curvature of the workers well, which keeps the basket in place unlike the existing round basket. The new basket is light in weight having more leaf capacity. Significant reduction in energy expenditure and MSDs suffered was observed while using improved basket over existing basket. 相似文献
953.
Merino GS Teixeira CS Schoenardie RP Merino EA Gontijo LA 《Work (Reading, Mass.)》2012,41(Z1):1045-1052
In product design, human factors are considered as an element of differentiation given that today's consumer demands are increasing. Safety, wellbeing, satisfaction, health, effectiveness, efficiency, and other aspects must be effectively incorporated into the product development process. This work proposes a usability assessment model that can be incorporated as an assessment tool. The methodological approach is settled in two stages. First a literature review focus specifically on usability and developing user-centred products. After this, a model of usability named Usa-Design (U-D?) is presented. Consisted of four phases: understanding the use context, pre-preliminary usability assessment (efficiency/effectiveness/satisfaction); assessment of usability principles and results, U-D? features are modular and flexible, allowing principles used in Phase 3 to be changed according to the needs and scenario of each situation. With qualitative/quantitative measurement scales of easy understanding and application, the model results are viable and applicable throughout all the product development process. 相似文献
954.
The noise caused by the movement of users on their chairs in the work environment may indicate structural weaknesses and risk, and still significantly reduce productivity by increasing employees stress level. By understanding the activities to be developed in a work place one may understand what should be necessary to a good development, thereafter a search for improvement of labor activity with the aim of better use of resources in the operation of product use may be done. The analysis of the incremental variation of noise in professional chairs aims to identify its origin and the time the emission of noise starts during the period of use, its development and the major causative agents. Determining the characteristics of the sound of different materials and adjustments mechanisms of the chair can determine how different materials interact with each other. The measurement of these noises in an acoustic isolated room using directional microphones, if recorded and analyzed properly makes it possible to investigate and orientate to suspect elements in order to propose solutions and identify the quality of other similar chairs. Based on the results recommendations can be established for the orientation of users, managers and people responsible for the acquisition of the products, inducing them to review the employment of materials and the choice of the processes of production. These aspects are not covered in the Brazilian ergonomics norms and standards in the use of chairs. 相似文献
955.
The ergonomic risks constitute a vital aspect of study and prevention for the worker's health, especially for people with different capacities. Very job has and implies certain type of risk for the worker's health, depending on the conditions it is done with the use of tools or without them. Aplicated techniques: posturogram, baropodometry, Schober test, biocinemátic chain test, Fukuda test, propioceptiva plataform in personnel with special capabilities. 相似文献
956.
This study presents the challenge involved in the negotiation and construction of a standard process in a major petroleum company that has the purpose of guiding the implementation of ergonomic studies in the development of projects, systemising the implementation of ergonomics design. The standard was created by a multi-disciplinary working group consisting of specialists in ergonomics, who work in a number of different areas of the company. The objective was to guide "how to" undertake ergonomics in all projects, taking into consideration the development of the ergonomic appraisals of work. It also established that all the process, in each project phase, should be accompanied by a specialist in ergonomics. This process as an innovation in the conception of projects in this company, signals a change of culture, and, for this reason requires broad dissemination throughout the several company leadership levels, and training of professionals in projects of ergonomics design. An implementation plan was also prepared and approved by the corporate governance, complementing the proposed challenge. In this way, this major oil company will implement new procedures of ergonomics design to promote health, safety, and wellbeing of the workforce, besides improving the performance and reliability of its systems and processes. 相似文献
957.
958.
We describe a Bayesian approach to evaluating children's abuse disclosures and review research demonstrating that children's disclosure of genital touch can be highly probative of sexual abuse, with the probative value depending on disclosure spontaneity and children's age. We discuss how some commentators understate the probative value of children's disclosures by: confusing the probability of abuse given disclosure with the probability of disclosure given abuse, assuming that children formally questioned about sexual abuse have a low prior probability of sexual abuse, misstating the probative value of abuse disclosure, and confusing the distinction between disclosure and nondisclosure with the distinction between true and false disclosures. We review interviewing methods that increase the probative value of disclosures, including interview instructions, narrative practice, noncontingent reinforcement, and questions about perpetrator/caregiver statements and children's reactions to the alleged abuse. 相似文献
959.
Everson MD Sandoval JM Berson N Crowson M Robinson H 《Journal of child sexual abuse》2012,21(1):72-90
In the absence of photographic or DNA evidence, a credible eyewitness, or perpetrator confession, forensic evaluators in cases of alleged child sexual abuse must rely on psychosocial or "soft" evidence, often requiring substantial professional judgment for case determination. This article offers a three-part rebuttal to Herman's (2009 ) argument that forensic decisions based on psychosocial evidence are fundamentally unreliable and that this conclusion represents settled science. The article also discusses the potentially adverse consequences of Herman's proposed reforms to forensic practice on child protection and prosecution efforts. 相似文献
960.
Natalia V. Czap Hans J. Czap Marianna Khachaturyan Gary D. Lynne Mark Burbach 《Journal of Socio》2012,41(5):642-653
This paper further tests dual interest theory and the metaeconomics approach to environmental choice, recognizing a possible role for empathy–sympathy (the basis for an internalized, shared other-interest) in tempering and conditioning the more fundamental tendency to pursue self-interest. To test, we focus on rivers flowing through agricultural areas carrying sediments, chemicals, and fertilizers which are making their way into downstream rivers and lakes. We conduct a framed laboratory experiment modeling this problem: farmers decide on the usage of conservation technology to lessen impacts on the water quality (i.e. on the commons, the capacity to absorb these wastes) in downstream areas, which is more costly than the alternative intensive technology. The results confirm our hypotheses, demonstrating that Upstream Farmers who practice conservation are tempering profit maximization with empathy-based, environmentally conscious behavior. Such behavior better serves the farmers’ own-interest, and also helps Downstream Water Users. Environmental economics models need to explicitly include empathy–sympathy and the moral–ethical context it produces, providing a more scientific basis for conservation policy and programs. 相似文献