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1.
网络用户的自我披露对以用户生成内容为业务基础的互联网企业具有战略意义.然而,隐私侵犯事件层出不穷.如何鼓励有隐私侵犯经历的用户持续披露个人信息对互联网企业至关重要.采用系统性随机分层抽样,结合代理理论和社会契约理论构建模型,研究了隐私侵犯经历对自我披露的作用机制.结果表明,隐私侵犯经历对自我披露意愿具有直接效应和间接效应:隐私侵犯经历与自我披露意愿之间存在强烈负向关系,并通过影响网络用户对隐私政策、隐私保护技术、行业自律和法律执行的有效性感知影响自我披露意愿.本研究阐明了隐私侵犯经历对自我披露的具体作用机制,为互联网企业鼓励有隐私侵犯经历的用户持续披露个人信息提供可操作性建议.  相似文献   
2.
Cascading failures often occur in congested complex networks. Cascading failures can be expressed as a three-phase process: generation, diffusion, and dissipation of congestion. Different from the betweenness centrality, a congestion function is proposed to represent the extent of congestion on a given node. Inspired by the restart process of a node, we introduce the concept of “delay time,” during which the overloaded node cannot receive or forward any traffic, so an intergradation between permanent removal and nonremoval is built and the flexibility of the presented model is demonstrated. Considering the connectivity of a network before and after cascading failures is not cracked because the overloaded node are not removed from network permanently in our model, a new evaluation function of network efficiency is also proposed to measure the damage caused by cascading failures. Finally, we investigate the effects of network structure and size, delay time, processing ability, and traffic generation speed on congestion propagation. Cascading processes composed of three phases and some factors affecting cascade propagation are uncovered as well.  相似文献   
3.
翻译是一个非常复杂的工程。译不仅要忠实地把原语作的意思表达清楚。还要把原语的各种积极修辞效果传达到译中。由于英汉“血缘”关系太少,许多修辞手段存在着本质的区别。特别体现在音韵以及典故习语表达方面。修辞效果在翻译过程中易于遗失。所以。要想方设法最大限度地保持原语的修辞效果。修辞效果的遗失与保特是一对矛盾,需辩证地看待。  相似文献   
4.
放射性重离子束在生命科学领域的应用   总被引:3,自引:0,他引:3  
应用放射性重离子注入活细胞和生物大分子,然后采用放射自显影,放射性测量和分子操作等研究技术,可对重离子注入质量沉积效应开展进一步的研究。放射性束还可应用于一些基本生物学问题的阐明及放射性药物的研制等方面。  相似文献   
5.
高校德育实效性是当前我国领域面临的一个非常重要的理论和实践课题。主要以德育过程为出发点来探讨其基本路径,认为将正面性与批判性、计划性与即时性、可接受性与发展性以及理论性与实践性进行聚合,有助于提高德育的效果。  相似文献   
6.
以管井井点降水设计和施工为研究对象,通过在渭河市政桥梁河道中深基坑中的应用实例,进行管井设计、布置、现场应用、观测、效果分析、对照,着重研究了降水理论与工程实践以及水位降落与时间的关系,为同类型桥梁水中深基坑施工提供借鉴。  相似文献   
7.
为了应对快速增长的带宽需求,解决非线性效应限制波分复用无源光网络(wavelength-division multiplexing passive optical network,WDM-PON)系统的传输距离和信道容量,尤其是四波混频(four-wave mixing,FWM)效应的问题。通过实验与仿真研究了25 Gb · s-1 · λ-1非归零码(non-return-to-zero,NRZ)信号经过25 km标准单模光纤(standard single-mode fiber,SSMF)传输时,FWM效应对系统所产生的影响。仿真结果表明,在信道间隔为200 GHz的12个波长传输系统中,除了第一个和最后一个信道之外,其他信道误码率(bit error rate,BER)都不能达到前向纠错码(forward error correction,FEC)的门限1.0 × 10-3。因此,在制定5G前传系统波长分布和信道间隔时,应充分考虑FWM串扰。  相似文献   
8.
Most air pollutants do not lead to specific diseases. Depending on the pollutant, the concentration and the duration of exposure, some organs are more affected than others. The most frequent disorders are those caused by irritant gases and particulates on the mucous membranes and respiratory organs. The consequences are eye, nose and throat inflammations, diminished lung function, increased susceptability to respiratory infection and a higher incidence of chronic bronchitis. These disorders and diseases are, of course, influenced by other factors as well, such as immune deficiency, allergies, occupational exposure to pollutants, and particularly smoking. The effects of air pollutants are, therefore, multifactorially conditioned and nonspecific disorders are placed in the foreground. Evidence for an association of air pollution with adverse effects on human health is drawn from three sources: animal experiments, experimental human exposures, and epidemiologic studies of exposed human populations. The burden of atmospheric pollution must be reduced to protect human health by an adequate safety margin. In particular, the increased sensitivity of sick and aged people as well as children should be taken into account. In defining the maximum emmission levels, preventive aspects should have priority so as to keep the risk of damage to health and the harmful influences on the environment to a minimum.This article Effects of atmospheric pollution on human health by H. U. Wanner is a revised version of the same article that was first published in the Proceedings of the 1990 European Aerosol Conference; special issue of the J. Aerosol Sci., Vol. 21, Suppl. 1 (1990) 389–396.Reprinted with kind permission from Pergamon Press Ltd, Headington Hill Hall, Oxford OX3 0BW, Great Britain.  相似文献   
9.
    
We analyze multicategory purchases of households by means of heterogeneous multivariate probit models that relate to partitions formed from a total of 25 product categories. We investigate both prior and post hoc partitions. We search model structures by a stochastic algorithm and estimate models by Markov chain Monte Carlo simulation. The best model in terms of cross‐validated log‐likelihood refers to a post hoc partition with two groups; the second‐best model considers all categories as one group. Among prior partitions with at least two category groups a five‐group model performs best. Effects on average basket value differ for the model with five prior category groups from those for the best‐performing model in 40% and 24% of the investigated categories for features and displays, respectively. In addition, the model with five prior category groups also underestimates total sales revenue across all categories by about 28%. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
The increasing amount of attention paid to longevity risk and funding for old age has created the need for precise mortality models and accurate future mortality forecasts. Orthogonal polynomials have been widely used in technical fields and there have also been applications in mortality modeling. In this paper we adopt a flexible functional form approach using two‐dimensional Legendre orthogonal polynomials to fit and forecast mortality rates. Unlike some of the existing mortality models in the literature, the model we propose does not impose any restrictions on the age, time or cohort structure of the data and thus allows for different model designs for different countries' mortality experience. We conduct an empirical study using male mortality data from a range of developed countries and explore the possibility of using age–time effects to capture cohort effects in the underlying mortality data. It is found that, for some countries, cohort dummies still need to be incorporated into the model. Moreover, when comparing the proposed model with well‐known mortality models in the literature, we find that our model provides comparable fitting but with a much smaller number of parameters. Based on 5‐year‐ahead mortality forecasts, it can be concluded that the proposed model improves the overall accuracy of the future mortality projection. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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