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61.
Xiaodong Gu 《Neural Processing Letters》2008,27(1):25-41
In this paper, we use Unit-linking PCNN (Pulse Coupled Neural Network), the simplified model of PCNN consisting of spiking
neurons, to code a 2-dimensional image into a 1-dimensional time sequence called global Unit-linking PCNN image icon or time
signature, including features of the original image and having the translation, rotation, and scale invariance. Dividing an
image into multiple parts can obtain local Unit-linking PCNN image icons corresponding to the image’s local regions, which
can reflect the local changes of the image. In the meantime, the global and the local Unit-linking PCNN image icons are used
in navigation, object detection, and image authentication. In navigation, global Unit-linking PCNN image icon shows qualified
performance especially in non-stationary-video navigation. Object detection using global Unit-linking PCNN image icon, is
independent of variances of translation, rotation, and scale, and object segmentation is avoided. In image authentication,
using local Unit-linking PCNN image icon can authenticate correctly some juggled images failed to authenticate by using local
histogram or local mean intensity, and can locate the juggled positions in the juggled images with some accuracy. 相似文献
62.
分层分类教学法在“计算机应用基础”课程中的应用 总被引:5,自引:0,他引:5
本文分析了目前计算机应用基础教学中存在的若干问题,并结合地方性高校的实际情况,针对各个问题分别提出了可行的对策,最后说明了实施的情况和取得的教学效果。 相似文献
63.
聚酰胺工程塑料的发展 总被引:5,自引:1,他引:5
介绍国内外聚酰胺工程塑料的发展历史和现状,各种聚酰胺新品种和新成型工艺技术的研究与开发动向,并对我国发展聚酰胺工程塑料提出了建议。 相似文献
64.
Previous studies on business simulation games (BSGs) have concluded that improved performance may not be the primary benefit of using BSGs, due to mixed results between student performance and perceptions. Two relevant and insightful issues attract our attention, namely, the impacts of the heterogeneous student population and the different complexity levels of BSG software. To address these issues, the present study aims to understand the relationship between student profile/characteristics and performance in the classroom with BSG-facilitated learning. An in-depth case study is conducted on a general college course designed to teach three different complexities of BSGs to students enrolled in different majors. Four student profile factors are individually tested for differences in performance scores as evaluated by the teacher. Additionally, the influences of 11 student characteristics are assessed with regard their self-reported perceived learning performances. Regression analysis and ANOVA are used to investigate the impacts of heterogeneous users and game complexity on student performance. Based on the regression analyses of the data collected from 43 respondents who participated in the general course, the study concludes that knowledge and skill may influence the heterogeneous student population; moreover, student participation and tacit learning preference improve performance, and students with an auditory learning preference or high learning motivation may not perform well in classroom BSG learning. However, the low value of adjusted R square implies that more dimensions or variables are needed to increase the explaining power of the performance scores in the regression analyses. In contrast, heterogeneous BSG software with different complexity levels present different results. The current research contributes practical and incremental knowledge on the complexity of heterogeneous BSG software on performance scores and the perceived learning performance of heterogeneous student populations. With the research limitations acknowledged, a series of suggestions for teachers pertaining to appropriate applications of BSGs in classes is offered as well as recommendations to BSG providers. Nevertheless, in-depth analyses are required, preferably with larger student population samples, to further explore the insignificant relationship between student perceptions and attitude under nonlinear extended complexity. 相似文献
65.
Jean‐Eudes Marvie Cyprien Buron Pascal Gautron Patrice Hirtzlin Gaël Sourimant 《Computer Graphics Forum》2012,31(7):2087-2095
GPU Shape Grammars provide a solution for interactive procedural generation, tuning and visualization of massive environment elements for both video games and production rendering. Our technique generates detailed models without explicit geometry storage. To this end we reformulate the grammar expansion for generation of detailed models at the tesselation control and geometry shader stages. Using the geometry generation capabilities of modern graphics hardware, our technique generated massive, highly detailed models. GPU Shape Grammars integrate within a scalable framework by introducing automatic generation of levels of detail at reduced cost. We apply our solution for interactive generation and rendering of scenes containing thousands of buildings and trees. 相似文献
66.
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68.
电子政务应用建设的可持续性发展研究 总被引:6,自引:0,他引:6
近年来,电子政务及其应用系统的建设正在我国方兴未艾,但建设过程中也出现了一些渚如盲目建没、应用系统水平太低等不良现象,这给建没部门和国家造成了巨大的经济损失。只有保持政务应用建设发展的可持续性,才能避免业务系统过早的被淘汰,避免建设资金的浪费,保证应用系统长期有效地发挥作用,真正获得电子政务建设带来的收益。 相似文献
69.
K. W. Brodlie D. A. Duce J. R. Gallop J. P. R. B. Walton J. D. Wood 《Computer Graphics Forum》2004,23(2):223-251
Visualization is a powerful tool for analyzing data and presenting results in science, engineering and medicine. This paper reviews ways in which it can be used in distributed and/or collaborative environments. Distributed visualization addresses a number of resource allocation problems, including the location of processing close to data for the minimization of data traffic. The advent of the Grid Computing paradigm and the link to Web Services provides fresh challenges and opportunities for distributed visualization—including the close coupling of simulations and visualizations in a steering environment. Recent developments in collaboration have seen the growth of specialized facilities (such as Access Grid) which have supplemented traditional desktop video conferencing using the Internet and multicast communications. Collaboration allows multiple users—possibly at remote sites—to take part in the visualization process at levels which range from the viewing of images to the shared control of the visualization methods. In this review, we present a model framework for distributed and collaborative visualization and assess a selection of visualization systems and frameworks for their use in a distributed or collaborative environment. We also discuss some examples of enabling technology and review recent work from research projects in this field. 相似文献
70.