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   495篇
  免费   37篇
  国内免费   5篇
电工技术   17篇
综合类   4篇
化学工业   143篇
金属工艺   16篇
机械仪表   22篇
建筑科学   21篇
能源动力   20篇
轻工业   53篇
水利工程   5篇
石油天然气   7篇
无线电   54篇
一般工业技术   82篇
冶金工业   12篇
原子能技术   8篇
自动化技术   73篇
  2023年   11篇
  2022年   17篇
  2021年   31篇
  2020年   24篇
  2019年   28篇
  2018年   45篇
  2017年   33篇
  2016年   31篇
  2015年   23篇
  2014年   28篇
  2013年   44篇
  2012年   28篇
  2011年   35篇
  2010年   28篇
  2009年   23篇
  2008年   19篇
  2007年   19篇
  2006年   15篇
  2005年   10篇
  2004年   6篇
  2003年   6篇
  2002年   5篇
  2001年   2篇
  2000年   3篇
  1999年   1篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1993年   3篇
  1991年   1篇
  1990年   1篇
  1988年   2篇
  1987年   1篇
  1984年   2篇
  1983年   1篇
  1981年   1篇
  1980年   3篇
  1979年   2篇
排序方式: 共有537条查询结果,搜索用时 15 毫秒
11.
As we approach 100 nm technology the interconnect issues are becoming one of the main concerns in the testing of gigahertz system-on-chips. Voltage distortion (noise) and delay violations (skew) contribute to the signal integrity loss and ultimately functional error, performance degradation and reliability problems. In this paper, we first define a model for integrity faults on the high-speed interconnects. Then, we present a BIST-based test methodology that includes two special cells to detect and measure noise and skew occurring on the interconnects of the gigahertz system-on-chips. Using an inexpensive test architecture the integrity information accumulated by these special cells can be scanned out for final test and reliability analysis.  相似文献   
12.
In this paper, we present the performance of multi-antenna selective combining decode-and-forward (SC-DF) relay networks over independent but non-identical Nakagami-m fading channels with imperfect channel estimation. The outage probability, moment generating function (MGF) and symbol error probability (SEP) will be derived in closed-form using the SNR statistical characteristics. To make the analysis trackable, we have derived the MGF and SEP for integer values of fading severity, m. Also, to make the relations more simple, we develop high signal to noise ratio (SNR) analysis for the performance metrics of our system. Subsequently, we propose optimal and adaptive power allocation algorithms along with the equal power allocation method. Finally, for comparison with analytical formulas, we perform some Monte-Carlo simulations.  相似文献   
13.
This paper presents a novel low-power majority function-based 1-bit full adder that uses MOS capacitors (MOSCAP) in its structure. It can work reliably at low supply voltage. In this design, the time-consuming XOR gates are eliminated. The circuits being studied are optimized for energy efficiency at 0.18-μm CMOS process technology. The adder cell is compared with seven widely used adders based on power consumption, speed, power-delay product (PDP) and area efficiency. Intensive simulation runs on a Cadence environment and HSPICE show that the new adder has more than 11% in power savings over a conventional 28-transistor CMOS adder. In addition, it consumes 30% less power than transmission function adder (TFA) and is 1.11 times faster.  相似文献   
14.
In this paper, we present a new view synthesis method in multiview camera configurations of Free viewpoint TV (FTV) where potential depth errors are considered. The emphasis is on the artifacts eliminating for photorealistic synthesis especially near object boundaries. In contrast to conventional techniques which ignore geometry errors, we first categorize the artifact cases and depth modes. Furthermore, this paper infers the complementarity principle of the artifacts from left and right references. This complementarity guarantees the effectiveness of our reliability-based synthesis. The reliability reasoning is crucial for artifacts reduction. The reliable and unreliable areas from different views can be correctly labeled. Then artifacts caused by unreliable pixels from one reference can be replaced by the reliable pixels from the other reference. As a final result, artifacts of novel view are demonstrated to be significantly reduced on different multiview sequences.  相似文献   
15.
16.
In this paper, the impact of the mixture of sodium dodecyl sulfate (SDS) + multi-wall carbon nanotubes (MWCNTs) + β-cyclodextrin on the quantity and initial rate of methane dissolved in water is investigated. The experiments were performed at a temperature range of 278.15–303.15 K and an initial pressure of 0.5 MPa. The experimental results show that simultaneous utilization of β-cyclodextrin (0.01 mass fraction), MWCNTs (0.0005 mass fraction), and SDS (0.001 mass fraction) at 278.15 K increases the amount and the rate of methane dissolution in water by 29.90% and 173.78%, respectively, compared to pure water. An increase in the temperature decreases the quantity and the initial rate of methane dissolution in all solutions containing additives. However, no consistent relationship is observed between the temperature and the enhancement percentage of solubility of methane in solutions containing additives.  相似文献   
17.
One of the approaches to increase the dexterity of a robot manipulating system is a design philosophy that consists of multiple robotic mechanisms. Applications of such a collection of manipulators can be in the design of a dextrous end-effector, a reconfigurable fixture to locate and grip various sized objects, or cooperative robotic arms which through their coordinated motions are able to accomplish a given task. Although the applications of such a design philosophy are endless, many problems still remain to be addressed. One of these problems is the control of the contact forces (grasping forces) between the mechanisms and the position of the grasped object. This article addresses this problem. First, a model of the mechanisms in contact with the grasped object is postulated; second, the problem of controlling the grasping forces and the position of the grasped object is formulated in the linear multi-input/multi-output system, and, finally, a centralized optimal controller is proposed for controlling the desired variables. The results of this article are demonstrated using two examples. One of the main advantages of the proposed controller is that it also shapes the transient response of the grasping force, which is an important consideration in cases when grasping fragile objects. © 1996 John Wiley & Sons, Inc.  相似文献   
18.
Water Resources Management - Groundwater is an important source to supply drinking water demands in both arid and semi-arid regions. Nevertheless, locating high quality drinking water is a major...  相似文献   
19.
ABSTRACT

Initiatives to operationalize the concept of resilience in the building industry are rapidly emerging. The concept of resilience has introduced a way to explore solutions to some important problems in the building industry. However, much of the work that has taken place to date represents activities generally assigned to risk management, which is discussed as being inherently insufficient for sustaining the functions of the built environment under stresses. This commentary considers the opportunities and limitations for mainstreaming resilience into building industry processes and actors. Barriers include indeterminate analytical meaning, event and performance uncertainty, immature regulatory standards setting, and untested enterprise economics. Further, the multiple outcomes of recovery and the relationship between building recovery and adaptation are discussed and, along with economics of resilience investments, a research need highlighted. A simple heuristic is presented to illustrate the complement of resilience to risk management and advance the integration of resilience into existing industry workflows.  相似文献   
20.
Following on from Part I of this review article that focuses on the suitability of Er3+-doped tellurium oxide glass for optical amplification in fiber, this Part II article describes how the fiber gain data were then employed to engineer amplification in waveguides, which can be integrated with semiconductor pump sources. The gain characteristics and bandwidth of a phosphate modified tellurite waveguide formed on a GaAs substrate are discussed. The limiting structural compatibility of Er3+-doped tellurite glass with polydimethylsiloxane polymer for active–passive integration is overcome by adopting a nanoscale super-lattice approach for waveguide engineering.  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