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   2625篇
  免费   454篇
  国内免费   205篇
电工技术   62篇
综合类   275篇
化学工业   56篇
金属工艺   48篇
机械仪表   157篇
建筑科学   79篇
矿业工程   28篇
能源动力   13篇
轻工业   47篇
水利工程   23篇
石油天然气   11篇
武器工业   21篇
无线电   562篇
一般工业技术   297篇
冶金工业   57篇
原子能技术   15篇
自动化技术   1533篇
  2024年   9篇
  2023年   96篇
  2022年   108篇
  2021年   110篇
  2020年   99篇
  2019年   97篇
  2018年   80篇
  2017年   109篇
  2016年   117篇
  2015年   115篇
  2014年   185篇
  2013年   205篇
  2012年   192篇
  2011年   203篇
  2010年   166篇
  2009年   155篇
  2008年   169篇
  2007年   174篇
  2006年   154篇
  2005年   116篇
  2004年   101篇
  2003年   89篇
  2002年   66篇
  2001年   58篇
  2000年   44篇
  1999年   39篇
  1998年   28篇
  1997年   21篇
  1996年   29篇
  1995年   13篇
  1994年   13篇
  1993年   7篇
  1992年   10篇
  1991年   10篇
  1990年   7篇
  1989年   13篇
  1988年   6篇
  1987年   9篇
  1986年   11篇
  1985年   8篇
  1984年   9篇
  1983年   8篇
  1982年   4篇
  1981年   6篇
  1979年   2篇
  1978年   3篇
  1975年   2篇
  1974年   2篇
  1973年   2篇
  1958年   1篇
排序方式: 共有3284条查询结果,搜索用时 46 毫秒
1.
2.
传统的基于稀疏表示的目标跟踪方法主要利用目标的灰度特征构建稀疏表示模型。由于灰度特征对光照变化敏感,这会影响目标跟踪在复杂场景下的鲁棒性。基于多源数据融合的目标跟踪可以明显提升目标跟踪鲁棒性,但如何有效融合不同维度,不同类型的多源目标特征成为基于多源数据融合的目标跟踪所要解决的关键问题。提出了一个基于目标状态以及灰度特征的稀疏表示目标跟踪方法。所提出的方法可通过基于核函数表示的稀疏表示模型,在探究目标状态以及灰度特征相关性的基础上,将两种不同维度的特征进行有效融合,提升目标跟踪在复杂场景下的鲁棒性。  相似文献   
3.
4.
Well-structured stimuli presentation is essential in eye-tracking research to test predefined hypotheses reliably and to conduct relevant gazing behavior studies. Several bottom-up factors associated with stimuli presentation (such as stimuli orientation, size etc.) can influence gazing behavior. However, only a small number of scientific papers address these factors in a sensory and consumer science context and thus provide guidance to practitioners. The two presented eye-tracking studies on food images aimed at evaluating the effect of the bottom-up factors stimulus size, background of the picture, orientation of food product presentation, the evaluated products and the number of alternatives. Significant effects of product group were found in the case of all eye-movement parameters except time to first fixation and first fixation duration. In contrary, orientation significantly influenced only the time to first fixation and first fixation duration parameters. Stimulus size significantly increased fixation and dwell count, while background showed no significant effects. Furthermore, significant relationships were found between the number of presented images and eye-movement and decision time. Less time was needed in 2AFC (alternative forced choice test), 3AFC and 4AFC and significantly more time was needed to choose one alternative out of 7AFC and 8AFC. The results of the two studies show that the investigated bottom-up factors can significantly influence gazing behavior, and therefore need to be carefully considered when planning or comparing results of eye-tracking experiments.  相似文献   
5.
6.
7.
Breast cancer is one of the most common types of cancer in women, and histopathological imaging is considered the gold standard for its diagnosis. However, the great complexity of histopathological images and the considerable workload make this work extremely time-consuming, and the results may be affected by the subjectivity of the pathologist. Therefore, the development of an accurate, automated method for analysis of histopathological images is critical to this field. In this article, we propose a deep learning method guided by the attention mechanism for fast and effective classification of haematoxylin and eosin-stained breast biopsy images. First, this method takes advantage of DenseNet and uses the feature map's information. Second, we introduce dilated convolution to produce a larger receptive field. Finally, spatial attention and channel attention are used to guide the extraction of the most useful visual features. With the use of fivefold cross-validation, the best model obtained an accuracy of 96.47% on the BACH2018 dataset. We also evaluated our method on other datasets, and the experimental results demonstrated that our model has reliable performance. This study indicates that our histopathological image classifier with a soft attention-guided deep learning model for breast cancer shows significantly better results than the latest methods. It has great potential as an effective tool for automatic evaluation of digital histopathological microscopic images for computer-aided diagnosis.  相似文献   
8.
Image segmentation is an important issue in many industrial processes, with high potential to enhance the manufacturing process derived from raw material imaging. For example, metal phases contained in microstructures yield information on the physical properties of the steel. Existing prior literature has been devoted to develop specific computer vision techniques able to tackle a single problem involving a particular type of metallographic image. However, the field lacks a comprehensive tutorial on the different types of techniques, methodologies, their generalizations and the algorithms that can be applied in each scenario. This paper aims to fill this gap. First, the typologies of computer vision techniques to perform the segmentation of metallographic images are reviewed and categorized in a taxonomy. Second, the potential utilization of pixel similarity is discussed by introducing novel deep learning-based ensemble techniques that exploit this information. Third, a thorough comparison of the reviewed techniques is carried out in two openly available real-world datasets, one of them being a newly published dataset directly provided by ArcelorMittal, which opens up the discussion on the strengths and weaknesses of each technique and the appropriate application framework for each one. Finally, the open challenges in the topic are discussed, aiming to provide guidance in future research to cover the existing gaps.  相似文献   
9.
The inspection of water conveyance tunnels plays an important role in water diversion projects. Siltation is an essential factor threatening the safety of water conveyance tunnels. Accurate and efficient identification of such siltation can reduce risks and enhance safety and reliability of these projects. The remotely operated vehicle (ROV) can detect such siltation. However, it needs to improve its intelligent recognition of image data it obtains. This paper introduces the idea of ensemble deep learning. Based on the VGG16 network, a compact convolutional neural network (CNN) is designed as a primary learner, called Silt-net, which is used to identify the siltation images. At the same time, the fully-connected network is applied as the meta-learner, and stacking ensemble learning is combined with the outputs of the primary classifiers to obtain satisfactory classification results. Finally, several evaluation metrics are used to measure the performance of the proposed method. The experimental results on the siltation dataset show that the classification accuracy of the proposed method reaches 97.2%, which is far better than the accuracy of other classifiers. Furthermore, the proposed method can weigh the accuracy and model complexity on a platform with limited computing resources.  相似文献   
10.
殷年 《安徽建筑》2006,13(5):189-190
简述航空影像数据的获取手段,针对不同的影像产品通过不同的处理方法来获取相应的数字产品,并简述了这些数字产品在城市规划建设中的应用。  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