首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3185篇
  免费   244篇
  国内免费   250篇
电工技术   175篇
综合类   1146篇
化学工业   161篇
金属工艺   32篇
机械仪表   101篇
建筑科学   130篇
矿业工程   19篇
能源动力   10篇
轻工业   67篇
水利工程   15篇
石油天然气   18篇
武器工业   12篇
无线电   231篇
一般工业技术   132篇
冶金工业   89篇
原子能技术   12篇
自动化技术   1329篇
  2024年   17篇
  2023年   47篇
  2022年   113篇
  2021年   133篇
  2020年   112篇
  2019年   86篇
  2018年   62篇
  2017年   71篇
  2016年   66篇
  2015年   112篇
  2014年   217篇
  2013年   175篇
  2012年   188篇
  2011年   249篇
  2010年   203篇
  2009年   195篇
  2008年   194篇
  2007年   241篇
  2006年   222篇
  2005年   179篇
  2004年   146篇
  2003年   135篇
  2002年   95篇
  2001年   71篇
  2000年   72篇
  1999年   52篇
  1998年   31篇
  1997年   36篇
  1996年   18篇
  1995年   23篇
  1994年   25篇
  1993年   11篇
  1992年   9篇
  1991年   15篇
  1990年   9篇
  1989年   10篇
  1988年   8篇
  1987年   2篇
  1986年   5篇
  1984年   1篇
  1983年   3篇
  1982年   3篇
  1981年   3篇
  1980年   1篇
  1979年   1篇
  1978年   3篇
  1977年   4篇
  1975年   3篇
  1972年   1篇
  1957年   1篇
排序方式: 共有3679条查询结果,搜索用时 15 毫秒
1.
Face aging (FA) for young faces refers to rendering the aging faces at target age for an individual, generally under 20s, which is an important topic of facial age analysis. Unlike traditional FA for adults, it is challenging to age children with one deep learning-based FA network, since there are deformations of facial shapes and variations of textural details. To alleviate the deficiency, a unified FA framework for young faces is proposed, which consists of two decoupled networks to apply aging image translation. It explicitly models transformations of geometry and appearance using two components: GD-GAN, which simulates the Geometric Deformation using Generative Adversarial Network; TV-GAN, which simulates the Textural Variations guided by the age-related saliency map. Extensive experiments demonstrate that our method has advantages over the state-of-the-art methods in terms of synthesizing visually plausible images for young faces, as well as preserving the personalized features.  相似文献   
2.
This paper investigates a renewable energy resource’s application to the Load–Frequency Control of interconnected power system. The Proportional-Integral (PI) controllers are replaced with Proportional-Integral Plus (PI+) controllers in a two area interconnected thermal power system without/with the fast acting energy storage devices and are designed based on Control Performance Standards (CPS) using conventional/Beta Wavelet Neural Network (BWNN) approaches. The energy storing devices Hydrogen generative Aqua Electroliser (HAE) with Fuel cell and Redox Flow Battery (RFB) are incorporated to the two area interconnected thermal power system to efficiently damp out the electromechanical oscillations in the power system because of their inherent efficient storage capacity in addition to the kinetic energy of the generator rotor, which can share the sudden changes in power requirements. The system was simulated and the frequency deviations in area 1 and area 2 and tie-line power deviations for 5% step- load disturbance in area 1 are obtained. The comparison of frequency deviations and tie-line power deviations of the two area interconnected thermal power system with HAE and RFB designed with BWNN controller reveals that the PI+ controller designed using BWNN approach is found to be superior than that of output response obtained using PI+ controller. Moreover the BWNN based PI+ controller exhibits a better transient and steady state response for the interconnected power system with Hydrogen generative Aqua Electroliser (AE) unit than that of the system with Redox Flow Battery (RFB) unit.  相似文献   
3.
Spontaneous mutations in the EEF1A2 gene cause epilepsy and severe neurological disabilities in children. The crystal structure of eEF1A2 protein purified from rabbit skeletal muscle reveals a post-translationally modified dimer that provides information about the sites of interaction with numerous binding partners, including itself, and maps these mutations onto the dimer and tetramer interfaces. The spatial locations of the side chain carboxylates of Glu301 and Glu374, to which phosphatidylethanolamine is uniquely attached via an amide bond, define the anchoring points of eEF1A2 to cellular membranes and interorganellar membrane contact sites. Additional bioinformatic and molecular modeling results provide novel structural insight into the demonstrated binding of eEF1A2 to SH3 domains, the common MAPK docking groove, filamentous actin, and phosphatidylinositol-4 kinase IIIβ. In this new light, the role of eEF1A2 as an ancient, multifaceted, and articulated G protein at the crossroads of autophagy, oncogenesis and viral replication appears very distant from the “canonical” one of delivering aminoacyl-tRNAs to the ribosome that has dominated the scene and much of the thinking for many decades.  相似文献   
4.
Neural Machine Translation (NMT) is an end-to-end learning approach for automated translation, overcoming the weaknesses of conventional phrase-based translation systems. Although NMT based systems have gained their popularity in commercial translation applications, there is still plenty of room for improvement. Being the most popular search algorithm in NMT, beam search is vital to the translation result. However, traditional beam search can produce duplicate or missing translation due to its target sequence selection strategy. Aiming to alleviate this problem, this paper proposed neural machine translation improvements based on a novel beam search evaluation function. And we use reinforcement learning to train a translation evaluation system to select better candidate words for generating translations. In the experiments, we conducted extensive experiments to evaluate our methods. CASIA corpus and the 1,000,000 pairs of bilingual corpora of NiuTrans are used in our experiments. The experiment results prove that the proposed methods can effectively improve the English to Chinese translation quality.  相似文献   
5.
In this article, the authors study the factorial structure of 2 versions (64 items and 32 items) of the Dutch translation of the Inventory of Interpersonal Problems (IIP; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) in both a clinical sample (n = 382) and a student sample (n = 287). First, the authors test whether both inventories are constituted by correlated uni-dimensional subscales, and they conclude that this is true only for the short version. Second, the authors study whether the correlations between the subscales follow a circumplex pattern. This proves to be true for both versions. Coefficients alpha and correlations between the IIP-64 and IIP-32 subscales are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
基于软交换的NAT/防火墙穿透技术研究   总被引:1,自引:0,他引:1  
通过对目前几种解决NAT(network addres stranslation)/防火墙穿逢方案的分析,提出了一种较易实现的穿透技术,并给出具体实现方案。  相似文献   
7.
基圆半径的确定方法,除了用图解法和试算法外,还可用解析法和图解分析法求解。4种方法各有优缺点,设计时要根据具体情况选择。  相似文献   
8.
With increasing globalization, communication across language and cultural boundaries is becoming an essential requirement of doing business, delivering education, and providing public services. Due to the considerable cost of human translation services, only a small fraction of text documents and an even smaller percentage of spoken encounters, such as international meetings and conferences, are translated, with most resorting to the use of a common language (e.g. English) or not taking place at all. Technology may provide a potentially revolutionary way out if real-time, domain-independent, simultaneous speech translation can be realized. In this paper, we present a simultaneous speech translation system based on statistical recognition and translation technology. We discuss the technology, various system improvements and propose mechanisms for user-friendly delivery of the result. Over extensive component and end-to-end system evaluations and comparisons with human translation performance, we conclude that machines can already deliver comprehensible simultaneous translation output. Moreover, while machine performance is affected by recognition errors (and thus can be improved), human performance is limited by the cognitive challenge of performing the task in real time.  相似文献   
9.
从语音、语义、结构3个方面分析了英语谚语的语言修辞特点,在此基础上,提出了等值、直译、意译、直意结合等4种汉译方法。另外,还提及了引申、对衬、格言、借用等4种具体翻译技巧。  相似文献   
10.
用户可以通过Internet访问和使用机器翻译系统,在线机器翻译系统可以帮助用户阅读网上外文材料。用户一般通过购买相关软件或访问提供在线翻译的网站来获取翻译服务,但是专用软件价格昂贵,或者获得的在线翻译效果不能令人满意。通过Web服务与J2EE技术的结合,提出了将机器翻译拳统包装为Web服务的机制,使企业和个人能够以较低的代价方便地享受更高质量的翻译服务。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号