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   2940篇
  免费   518篇
  国内免费   212篇
电工技术   70篇
综合类   333篇
化学工业   56篇
金属工艺   48篇
机械仪表   156篇
建筑科学   77篇
矿业工程   27篇
能源动力   14篇
轻工业   46篇
水利工程   22篇
石油天然气   10篇
武器工业   26篇
无线电   827篇
一般工业技术   300篇
冶金工业   48篇
原子能技术   16篇
自动化技术   1594篇
  2024年   8篇
  2023年   97篇
  2022年   111篇
  2021年   110篇
  2020年   98篇
  2019年   105篇
  2018年   88篇
  2017年   120篇
  2016年   132篇
  2015年   135篇
  2014年   210篇
  2013年   223篇
  2012年   220篇
  2011年   230篇
  2010年   197篇
  2009年   186篇
  2008年   197篇
  2007年   201篇
  2006年   176篇
  2005年   127篇
  2004年   105篇
  2003年   101篇
  2002年   67篇
  2001年   68篇
  2000年   59篇
  1999年   47篇
  1998年   30篇
  1997年   23篇
  1996年   30篇
  1995年   15篇
  1994年   16篇
  1993年   12篇
  1992年   19篇
  1991年   10篇
  1990年   9篇
  1989年   12篇
  1988年   5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3670条查询结果,搜索用时 15 毫秒
1.
2.
3.
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   
4.
5.
6.
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   
7.
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   
8.
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   
9.
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   
10.
本文引入环境形象整体现,在环境结构原型分析的基础上结合实践探讨了住宅小区环境整体性设计,旨在强调设计的整体性及尝试设计方法上的新思路。  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