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51.
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53.
Marcelo Siqueira Longin Jan Latecki Nicholas Tustison Jean Gallier James Gee 《Journal of Mathematical Imaging and Vision》2008,30(3):249-274
We present here a new randomized algorithm for repairing the topology of objects represented by 3D binary digital images.
By “repairing the topology”, we mean a systematic way of modifying a given binary image in order to produce a similar binary
image which is guaranteed to be well-composed. A 3D binary digital image is said to be well-composed if, and only if, the square faces shared by background and foreground
voxels form a 2D manifold. Well-composed images enjoy some special properties which can make such images very desirable in
practical applications. For instance, well-known algorithms for extracting surfaces from and thinning binary images can be
simplified and optimized for speed if the input image is assumed to be well-composed. Furthermore, some algorithms for computing
surface curvature and extracting adaptive triangulated surfaces, directly from the binary data, can only be applied to well-composed
images. Finally, we introduce an extension of the aforementioned algorithm to repairing 3D digital multivalued images. Such
an algorithm finds application in repairing segmented images resulting from multi-object segmentations of other 3D digital
multivalued images.
相似文献
James GeeEmail: |
54.
A. Z. Kouzani 《Machine Vision and Applications》2008,19(4):223-248
There has been an increasing interest in face recognition in recent years. Many recognition methods have been developed so
far, some very encouraging. A key remaining issue is the existence of variations in the input face image. Today, methods exist
that can handle specific image variations. But we are yet to see methods that can be used more effectively in unconstrained
situations. This paper presents a method that can handle partial translation, rotation, or scale variations in the input face
image. The principal is to automatically identify objects within images using their partial self-similarities. The paper presents
two recognition methods which can be used to recognise objects within images. A face recognition system is then presented
that is insensitive to limited translation, rotation, or scale variations in the input face image. The performance of the
system is evaluated through four experiments. The results show that the system achieves higher recognition rates than those
of a number of existing approaches.
The author would like to thank the Australian Research Council (ARC) which supports this research with a Discovery Grant. 相似文献
55.
This paper presents a genetic based incremental neural network (GINeN) for the segmentation of tissues in ultrasound images. Performances of the GINeN and the Kohonen network are investigated for tissue segmentation in ultrasound images. Feature extraction is carried out by using continuous wavelet transform. Pixel intensities at the same spatial location on 12 wavelet planes and on the original image are considered as features, leading to 13-dimensional feature vectors. The same training set is used for the training of the Kohonen network and the GINeN.
This paper proposes the use of wavelet transform and genetic based incremental neural network together in order to increase the segmentation performance. It is observed that genetic based incremental neural network gives satisfactory segmentation performance for ultrasound images. 相似文献
56.
The color composite digital mapping camera (DMC) images are produced by the post-processing software of Z/I imaging. But the
failure of radiometric correction in post-processing leads to residual radiometric differences between CCD images, which then
affect the quality of the images in further applications. This paper, via analyzing the characters and causes of such a phenomenon,
proposes a repair approach based on hierarchical location using edge curve. The approach employs a hierarchical strategy to
locate the transition area and seam-line automatically and then repair the image through the global reconstruction between
CCD images and the local reconstruction in the transition area. Experiments indicate that the approach proposed by this paper
is feasible and can improve the quality of images effectively.
Supported by the National Basic Research Program of China (Grant No. 2006CB701302) and the Youth Fundation Plan of Wuhan (Grant
No. 200750731253) 相似文献
57.
介绍了多媒体图象数据查询和检索的系统结构;阐述了图象数据查询和检索的基本过程和相关技术;提出了图象分割、特征提取、相似匹配、快速存取的具体算法,并对它们进行了详细分析。 相似文献
58.
LED显示屏主要用来显示文字信息,它的控制系统多为单片机控制,通信方式为rs232或者低速的以太网.考虑到单片机的处理能力和控制系统成本的原因,一般控制系统都没有设置字库,所以LED显示屏上显示的文字一般都用位图点阵信息表示.但基于文本的位图数据量很大,且控制系统的通讯传输速度低下,在发送大量显示画面时位图数据的压缩就非常重要.由于控制系统单片机的处理能力有限,JPEG、GIF等图像压缩算法难以实现.基于行程编码图像压缩算法计算量小、适合单片机处理,而且对于文字位图的压缩率较高. 相似文献
59.
在快速的城市化进程中,遥感技术可以为城市土地利用变化提供直观、准确、同步的信息。本体是对概念化的明确描述和说明,更接近于认知模型,易于理解和共享;同时又能以计算机可操作的形式化语言明确表达目标领域的概念体系及其蕴含的语义。因此,在分析和借鉴现有相关研究的基础上,将本体、语义思想引入到遥感影像表达,建立了基于本体的城市遥感影像解译应用语义模型和解译框架,应用此框架将有助于提高城市遥感影像解译的精度与效率,对推动遥感技术在城市相关领域中的应用有着积极的意义。 相似文献
60.
针对高分辨率可见光图像中靠岸舰船的灰度特征和纹理特征与港口设施极为相似而难以自动检测的问题,提出了一种利用邻域自相似局部特征提取算子提取港口舰船局部显著性特征,经过特征空间分析,并利用先验知识信息,自动检测港口舰船的算法和处理流程。实验结果表明,该处理方法具有较好的可操作性和鲁棒性,能够快速准确地检测出港口舰船目标。 相似文献