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   3003篇
  免费   73篇
  国内免费   7篇
电工技术   60篇
综合类   1篇
化学工业   621篇
金属工艺   39篇
机械仪表   57篇
建筑科学   153篇
矿业工程   21篇
能源动力   68篇
轻工业   253篇
水利工程   14篇
石油天然气   6篇
武器工业   1篇
无线电   255篇
一般工业技术   406篇
冶金工业   739篇
原子能技术   30篇
自动化技术   359篇
  2021年   33篇
  2020年   17篇
  2019年   29篇
  2018年   41篇
  2017年   44篇
  2016年   36篇
  2015年   39篇
  2014年   48篇
  2013年   187篇
  2012年   83篇
  2011年   113篇
  2010年   95篇
  2009年   108篇
  2008年   118篇
  2007年   109篇
  2006年   115篇
  2005年   100篇
  2004年   67篇
  2003年   55篇
  2002年   76篇
  2001年   41篇
  2000年   62篇
  1999年   51篇
  1998年   126篇
  1997年   99篇
  1996年   80篇
  1995年   53篇
  1994年   58篇
  1993年   49篇
  1992年   43篇
  1991年   25篇
  1990年   33篇
  1989年   27篇
  1988年   38篇
  1986年   30篇
  1985年   43篇
  1984年   56篇
  1983年   48篇
  1982年   35篇
  1981年   44篇
  1980年   52篇
  1979年   43篇
  1978年   34篇
  1977年   30篇
  1976年   40篇
  1975年   32篇
  1974年   27篇
  1973年   32篇
  1971年   22篇
  1970年   19篇
排序方式: 共有3083条查询结果,搜索用时 62 毫秒
71.
This paper studies the multifunctionality of dialogue utterances, i.e. the phenomenon that utterances in dialogue often have more than one communicative function. It is argued that this phenomenon can be explained by analyzing the participation in dialogue as involving the performance of several types of activity in parallel, relating to different dimensions of communication. The multifunctionality of dialogue utterances is studied by (1) redefining the notion of ‘utterance’ in a rigorous manner (calling the revised notion ‘functional segment’), and (2) empirically investigating the multifunctionality of functional segments in a corpus of dialogues, annotated with a rich, multidimensional annotation schema. It is shown that, when communicative functions are assigned to functional segments, thereby eliminating every form of segmentation-related multifunctionality, an average multifunctionality is found between 1.8 and 3.6, depending on what is considered to count as a segment's communicative function. Moreover, a good understanding of the nature of the relations among the various multiple functions that a segment may have, and of the relations between functional segments and other units in dialogue segmentation, opens the way for defining a multidimensional computational update semantics for dialogue interpretation.  相似文献   
72.
73.
74.
75.
Motivated by a case study at a radiology practice, we analyze the incremental benefits of RFID technology over barcodes for managing pharmaceutical inventories. Unlike barcode technology, RFID enables accurate real-time visibility, which in turn enables several process improvements. We analyze the impact of automatic counting and discuss the system redesign critical to optimizing the inventory policy and eliminating shrinkage. We show that continuous review is superior to periodic review whenever accurate real-time information is available at no additional cost. We explain how RFID-enabled strategies vary with inventory parameters and provide a cost-benefit analysis for the implementation of RFID for the radiology practice.  相似文献   
76.
Modeling Content for Semantic-Level Querying of Multimedia   总被引:2,自引:0,他引:2  
Many semantic content-based models have been developed for modeling video and audio in order to enable information retrieval based on semantic content. The level of querying of the media depends upon the semantic aspects modeled. This paper proposes a semantic content-based model for semantic-level querying that makes full use of the explicit media structure, objects, spatial relationships between objects, events and actions involving objects, temporal relationships between events and actions, and integration between syntactic and semantic information.  相似文献   
77.
提出了一种新的多视点拼图,称之为平行拼图,平行拼图不仅可以应用到基于图像的绘制技术中,而且可以广泛地运用于基于图像的三维重建。该文设计了从真实照片中得到高分辨率平行拼图的算法,建立了从平行拼图得到高精度绘制输出的数学模型,讨论了用照片建立平行拼图的精度上限,并且给出了良好的实验结果。  相似文献   
78.
Synchronization of signal packets is required in networks in order to route the packets. Due to changes in the interarrival times of the packets the inputs to the routing circuits may exhibit oscillatory metastability. Oscillatory metastability can be eliminated in optical circuits by the addition of logic signal stretch. This can be done because the propagation time of optics can be precisely controlled. An algorithm for inserting logic signal stretch to eliminate oscillatory metastability is presented herein.  相似文献   
79.
We construct and analyze multigrid methods for discretized self-adjoint elliptic problems on triangular surfaces in ${\mathbb{R}^3}$ . The methods involve the same weights for restriction and prolongation as in the case of planar triangulations and therefore are easy to implement. We prove logarithmic bounds of the convergence rates with constants solely depending on the ellipticity, the smoothers and on the regularity of the triangles forming the triangular surface. Our theoretical results are illustrated by numerical computations.  相似文献   
80.
The following paper reviews the possibilities of encapsulating existing legacy software for reuse in new distributed architectures. It suggests wrapping as an alternative strategy to reengineering and redevelopment. It then defines the levels of granularity at which software can be encapsulated before going on to describe how to construct a wrapper and how to adapt host programs for wrapping. Some wrapping products are discussed and the state of the art summarized. The advantage of wrapping over conventional reengineering is the low cost and even lower risks involved. This is the driving force in the search for improved wrapping technology. This revised version was published online in June 2006 with corrections to the Cover Date.  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