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201.
中国产业结构变动与就业水平的实证研究 总被引:2,自引:0,他引:2
文章运用时间序列和计量模型研究了中国产业结构与就业水平之间的发展关系.首先运用格兰杰因果检验分析了第一、二、三次产业的产值与其就业之间的因果影响关系,继而从产值与就业两个角度定量分析了第一、二、三次产业各自对总就业水平的贡献,得出结论:第一产业和第三产业是劳动力就业的决定因素,而第二产业不是就业的决定因素;从产值角度来看,第三产业对劳动力就业的贡献最大,从就业角度来看,第一产业的就业对总体就业水平的贡献最高,其次是第三产业,而第二产业的就业对总体就业水平的贡献最小.最后根据研究结论提出相应的建议措施. 相似文献
202.
中国基础设施投资对经济增长波动的冲击效应分析 总被引:1,自引:1,他引:1
基础设施是经济发展的重要影响因素,而“基础设施投资促进经济发展”这一主流观点已得到广泛共识,但人们对经济增长与基础设施的探讨仅局限于总量的分析框架,并未对基础设施的类型加以区分,更没发现经济发展的不同阶段对基础设施的需求结构也是不同的。而以“基础设施投资促进经济发展”为出发点,将基础设施投资细分为生产性、生活性、社会性基础设施投资,并分别讨论其对经济的影响。通过邹检验发现:自1994年以来,基础设施投资冲击改变了中国经济增长的特征。其结论是生产性、生活性基础设施对经济增长的影响是明确的、同步的,但社会性基础设施对经济增长的作用是不确定的。因此,加强社会性基础设施投资是一个渐进地逐步推进的过程。 相似文献
203.
大学生数学成绩影响因素的实证分析 总被引:3,自引:0,他引:3
伴随着近几年高校的扩大招生,部分大学生的数学成绩显著下降。用统计学软件SPSS 13.0对哈尔滨工程大学部分学生的高等数学成绩及其相关因素进行统计分析,考察学生的高考数学成绩、性别、生源所在地等因素对其大学数学成绩的影响。在给出了一些切实可行的对策和建议的同时,指出培养大学生学习的主动性和研究探索精神,已经成为当今高校教师和教育工作者培养高素质人才和提高教学水平的关键。 相似文献
204.
摘 要:商业银行无形资产是形成商业银行核心竞争力的基础和产生超额收益的源泉,加强商业银行无形资产统计工作,有利于充分揭示商业银行无形资产基本内容和对核心竞争力的影响。笔者认为,目前我国商业银行无形资产统计指标体系设置不完整,统计制度不健全,统计内容不全面,统计分析不深入,影响经济决策。笔者认为,完善商业银行无形资产统计制度时,应从组织结构类、客户关系类、知识创新类和人力资本类等四个方面对无形资产进行统计,逐步细化统计指标,明确具体的统计内容,建立、健全无形资产价值信息系统,深化无形资产统计分析工作,以此为基础,提出提高商业银行核心竞争力的基本策略。 相似文献
205.
基层统计是中国政府统计的基础,提高警惕基层统计质量是提高中国统计数据质量的关键,而建立与社会经济体制相适应的基层统计管理制度又是提高基层统计质量的根本保证.在社会主义市场经济体制下,我国基层统计环境发生了全新变化,为了适应新的变化,必须建立基层统计代理制,基层统计代理制是统计经济成分多元化,社会分工细化,统计利益市场化和统计工作规范化的必然要求 .在我国建立基层统计代理制具有法律可行性,技术档行性和经济可行性.随着统计代理制的实施,我国基层统计的数据来源将会更有保障,数据质量将会稳步提升,工作效率将会大大提高,从而促进我国统计事业兴旺发达. 相似文献
206.
The plant ‘Heat Rate’ (HR) is a measure of overall efficiency of a thermal power generating system. It depends on a large number of factors, some of which are non-measurable, while data relating to others are seldom available and recorded. However, coal quality (expressed in terms of ‘effective heat value’ (EHV) as kcal/kg) transpires to be one of the important factors that influences HR values and data on EHV are available in any thermal power generating system. In the present work, we propose a prediction interval of the HR values on the basis of only EHV, keeping in mind that coal quality is one of the important (but not the only) factors that have a pronounced effect on the combustion process and hence on HR. The underlying theory borrows the idea of providing simultaneous confidence interval (SCI) to the coefficients of a p-th p(≥1) order autoregressive model (AR(p)). The theory has been substantiated with the help of real life data from a power utility (after suitable base and scale transformation of the data to maintain the confidentiality of the classified document). Scope for formulating strategies to enhance the economy of a thermal power generating system has also been explored. 相似文献
207.
杨武云 《西南科技大学学报(哲学社会科学版)》1992,(1)
应用染色体组分析法,对新疆节节麦、黄河流域节节麦、伊朗节节麦和中东节节麦的D染色体组进行了较系统的比较分析,结果表明:新疆节节麦与伊朗、中东两地节节麦在染色体组水平上无明显差异,其差异仅体现在染色体的细微结构组成上;臂内倒位是引起染色体结构组成上细微分化的主要原因。黄河流域节节麦与新疆节节麦的染色体组极为相近;其D组染色体无论在染色体组水平上,还是在染色体细微结构组成上均无差异。本文还就中国节节麦与中国特有六倍体普通小麦的起源演化,中国节节麦种质资源在现代小麦育种中的应用等问题进行了讨论。 相似文献
208.
The EPA Health Risk Assessment of Methylcyclopentadienyl Manganese Tricarbonyl (MMT) 总被引:1,自引:0,他引:1
This paper describes the U.S. Environmental Protection Agency's assessment of potential health risks associated with the possible widespread use of a manganese (Mn)-based fuel additive, methylcyclopentadienyl manganese tricarbonyl (MMT). This assessment was significant in several respects and may be instructive in identifying certain methodological issues of general relevance to risk assessment. A major feature of the inhalation health risk assessment was the derivation of Mn inhalation reference concentration (RfC) estimates using various statistical approaches, including benchmark dose and Bayesian analyses. The exposure assessment component used data from the Particle Total Exposure Assessment Methodology (PTEAM) study and other sources to estimate personal exposure levels of particulate Mn attributable to the permitted use of MMT in leaded gasoline in Riverside, CA, at the time of the PTEAM study; on this basis it was then possible to predict a distribution of possible future exposure levels associated with the use of MMT in all unleaded gasoline. Qualitative as well as quantitative aspects of the risk characterization are summarized, along with inherent uncertainties due to data limitations. 相似文献
209.
Topics in Microbial Risk Assessment: Dynamic Flow Tree Process 总被引:5,自引:0,他引:5
Microbial risk assessment is emerging as a new discipline in risk assessment. A systematic approach to microbial risk assessment is presented that employs data analysis for developing parsimonious models and accounts formally for the variability and uncertainty of model inputs using analysis of variance and Monte Carlo simulation. The purpose of the paper is to raise and examine issues in conducting microbial risk assessments. The enteric pathogen Escherichia coli O157:H7 was selected as an example for this study due to its significance to public health. The framework for our work is consistent with the risk assessment components described by the National Research Council in 1983 (hazard identification; exposure assessment; dose-response assessment; and risk characterization). Exposure assessment focuses on hamburgers, cooked a range of temperatures from rare to well done, the latter typical for fast food restaurants. Features of the model include predictive microbiology components that account for random stochastic growth and death of organisms in hamburger. For dose-response modeling, Shigella data from human feeding studies were used as a surrogate for E. coli O157:H7. Risks were calculated using a threshold model and an alternative nonthreshold model. The 95% probability intervals for risk of illness for product cooked to a given internal temperature spanned five orders of magnitude for these models. The existence of even a small threshold has a dramatic impact on the estimated risk. 相似文献
210.
Gray George M. Allen Jon C. Burmaster David E. Gage Stuart H. Hammitt James K. Kaplan Stanley Keeney Ralph L. Morse Joseph G. North D. Warner Nyrop Jan P. Stahevitch Alina Williams Richard 《Risk analysis》1998,18(6):773-780
The North American Free Trade Agreement (NAFTA) and the General Agreement on Tariffs and Trade (GATT) have focused attention on risk assessment of potential insect, weed, and animal pests and diseases of livestock. These risks have traditionally been addressed through quarantine protocols ranging from limits on the geographical areas from which a product may originate, postharvest disinfestation procedures like fumigation, and inspections at points of export and import, to outright bans. To ensure that plant and animal protection measures are not used as nontariff trade barriers, GATT and NAFTA require pest risk analysis (PRA) to support quarantine decisions. The increased emphasis on PRA has spurred multiple efforts at the national and international level to design frameworks for the conduct of these analyses. As approaches to pest risk analysis proliferate, and the importance of the analyses grows, concerns have arisen about the scientific and technical conduct of pest risk analysis. In January of 1997, the Harvard Center for Risk Analysis (HCRA) held an invitation-only workshop in Washington, D.C. to bring experts in risk analysis and pest characterization together to develop general principles for pest risk analysis. Workshop participants examined current frameworks for PRA, discussed strengths and weaknesses of the approaches, and formulated principles, based on years of experience with risk analysis in other setting and knowledge of the issues specific to analysis of pests. The principles developed highlight the both the similarities of pest risk analysis to other forms of risk analysis, and its unique attributes. 相似文献