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   180篇
  免费   7篇
  国内免费   35篇
综合类   4篇
化学工业   16篇
金属工艺   10篇
机械仪表   14篇
建筑科学   2篇
矿业工程   1篇
轻工业   65篇
石油天然气   8篇
无线电   22篇
一般工业技术   30篇
冶金工业   5篇
原子能技术   1篇
自动化技术   44篇
  2024年   2篇
  2023年   2篇
  2022年   8篇
  2021年   8篇
  2020年   18篇
  2019年   9篇
  2018年   15篇
  2017年   14篇
  2016年   12篇
  2015年   7篇
  2014年   14篇
  2013年   10篇
  2012年   18篇
  2011年   12篇
  2010年   11篇
  2009年   7篇
  2008年   12篇
  2007年   9篇
  2006年   5篇
  2005年   11篇
  2004年   4篇
  2003年   4篇
  2002年   3篇
  2000年   1篇
  1999年   1篇
  1996年   1篇
  1994年   2篇
  1993年   2篇
排序方式: 共有222条查询结果,搜索用时 15 毫秒
1.
Multimedia Tools and Applications - To address the problems of insufficient detail extraction and long training time in the super-resolution reconstruction of chest X-ray images, a method of chest...  相似文献   
2.
eCRM (electronic Customer Relationship Management) systems focus on using the web-site as the main interaction channel for businesses to simulate an old fashioned one-to-one direct relationship—high touch—with customers. In this research two distinct but related concepts, media richness from the Human Computer Interaction and Computer Mediated Communication fields and perceived interactivity from the Marketing and MIS fields, are disentangled and their unique impacts on technology acceptance variables are examined in the eCRM Acceptance Model. The present study contributes in extending the Technology Acceptance Model for the eCRM context and in establishing media richness and perceived interactivity as antecedents to perceived usefulness and perceived ease of use. Our research model integrates system perception (e.g., perceived usefulness and perceived ease of use) and subjective outcome measures (e.g., decision satisfaction) in a single model to fully understand the impact of eCRM “touch” design perceived by e-customers on their intention to return after the initial visit. An experimental survey of two culture groups (independent vs. interdependent self-construal) of technology savvy, young college students reveals that culture value-orientation (e.g., self-construal) moderates the effect of decision satisfaction on behavior intention to return in our eCRM Acceptance model. Findings of this research thus have significant theoretical and managerial implications.  相似文献   
3.
粘土矿物是低渗砂岩储层的主要胶结物,对储层物性及开发过程中储层物性变化趋势有着重要的影响和控制作用。另外,粘土矿物也蕴含着大量沉积环境介质的物理化学信息,认识其自然规律,可以有效地指导预测有利储层,认识和改造油层。以鄂尔多斯盆地砂岩储层中的粘土矿物为研究对象,探讨分析粘土矿物对低渗储层性质的影响,该研究对含油气盆地低渗储层有效开发具有一定的参考价值。  相似文献   
4.
为了解决信息工程监理中各风险的重要性问题,根据各风险之间的相互作用和影响的原理,运用PageRank算法对风险进行排序,为信息工程监理的风险评估提供了新的研究方法.  相似文献   
5.
Localized geometric warping of images is known to be one of the most effective attacks against image watermarking systems. However, the existing local geometrical attacks, when applied to images with regular structures, cause perceptible distortion because they are not adaptive to the content of the images. In this work, we present a multi-scale directional smoothing framework in which local displacement vectors are smoothed by locally adaptive directional kernels. Both the displacement vectors for large structures and those for fine structures are constrained by using a multi-scale pyramid. Subjective tests and objective metrics show that our proposed approach can effectively enhance the perceptual quality of the image after geometric attacks. The test of the attacking effects on two typical watermarking systems demonstrates that our approach does not degrade the attacking effects for Markov random field generated displacement field.  相似文献   
6.
测量不确定度是对测量结果的质量的定量评定,意味着对测量结果可信性、有效性的怀疑程度或不肯定程度。本文依据JJF1059-1999《测量不确定度的评定和表示》,计算实验过程中各因素引入的不确定度,建立葡萄酒中总酸的测定不确定度评定方法。  相似文献   
7.
模糊对象的空间Co-location模式挖掘研究   总被引:1,自引:0,他引:1  
空间co-location模式表示的是空间对象的实例在一个相同的区域内频繁地空间并置.过去人们已经对确定及不确定数据的co-location模式挖掘问题进行了一些研究,但是针对模糊对象上进行的研究还没有.模糊对象在许多领域里都有着非常重要的应用,比如生物医学图像数据库和GIS.该文研究模糊对象的空间co-locatio...  相似文献   
8.
一种基于3D-DCT的彩色图像信息隐藏算法   总被引:4,自引:0,他引:4  
提出了一种基于3D-DCT的彩色图像信息隐藏盲检测算法.本算法不但可以在512× 512的RGB彩色图像中嵌入多达2048字节的数据,而且实现了完全盲检测,即在信息检测时,该 算法不需要原始图像和任何附加信息.同时,采用3D-DCT和算法中的信息嵌入方式,能充分地 利用信息载体的容量,很好地平衡隐藏信息的不可见性和稳健性之间的矛盾.算法采用了纠错编 码技术和数据扰乱技术,以提高算法抵抗各类攻击的性能.实验证明,该算法所隐藏的信息在 StirMark的攻击下,对高达3×10-1~10-2的误比特率,仍具有很好的稳健性.  相似文献   
9.
国标GB 5009.225-2016《食品安全国家标准酒中乙醇浓度的测定》第二法为酒精计法,标准方法将制备好的试样注入100m L或200m L量筒中用分度值为0.1%vol的精密酒精计读取酒精度值,在实际实验中无法实现该操作。本文通过对该国标方法的改进,能准确、高效的完成酒精计法测定酒中乙醇浓度。  相似文献   
10.
Bifidobacterium longum is a very important gram-positive non-pathogenic bacterium in the human gastrointestinal tract for keeping the digestive and immune system healthy. Isocitrate dehydrogenase (IDH) from B. longum (BlIDH), a novel member in Type II subfamily, was overexpressed, purified and biochemically characterized in detail. The active form of BlIDH was an 83-kDa homodimer. Kinetic analysis showed BlIDH was a NADP+-dependent IDH (NADP-IDH), with a 567- and 193-fold preference for NADP+ over NAD+ in the presence of Mg2+ and Mn2+, respectively. The maximal activity for BlIDH occurred at 60 °C (with Mn2+) and 65 °C (with Mg2+), and pH 7.5 (with Mn2+) and pH 8.0 (with Mg2+). Heat-inactivation profiles revealed that BlIDH retained 50% of maximal activity after incubation at 45 °C for 20 min with either Mn2+ or Mg2+. Furthermore, the coenzyme specificity of BlIDH can be completely reversed from NADP+ to NAD+ by a factor of 2387 by replacing six residues. This current work, the first report on the coenzyme specificity conversion of Type II NADP-IDHs, would provide better insight into the evolution of NADP+ use by the IDH family.  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