全文获取类型
收费全文 | 2504篇 |
免费 | 16篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 7篇 |
综合类 | 1篇 |
化学工业 | 110篇 |
金属工艺 | 17篇 |
机械仪表 | 22篇 |
建筑科学 | 28篇 |
矿业工程 | 2篇 |
能源动力 | 48篇 |
轻工业 | 56篇 |
水利工程 | 3篇 |
石油天然气 | 6篇 |
无线电 | 45篇 |
一般工业技术 | 103篇 |
冶金工业 | 1967篇 |
原子能技术 | 28篇 |
自动化技术 | 79篇 |
出版年
2024年 | 2篇 |
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 16篇 |
2020年 | 21篇 |
2019年 | 24篇 |
2018年 | 28篇 |
2017年 | 16篇 |
2016年 | 21篇 |
2015年 | 15篇 |
2014年 | 18篇 |
2013年 | 62篇 |
2012年 | 36篇 |
2011年 | 41篇 |
2010年 | 38篇 |
2009年 | 33篇 |
2008年 | 21篇 |
2007年 | 23篇 |
2006年 | 24篇 |
2005年 | 14篇 |
2004年 | 17篇 |
2003年 | 11篇 |
2002年 | 11篇 |
2001年 | 8篇 |
1999年 | 55篇 |
1998年 | 597篇 |
1997年 | 318篇 |
1996年 | 249篇 |
1995年 | 154篇 |
1994年 | 108篇 |
1993年 | 108篇 |
1992年 | 23篇 |
1991年 | 42篇 |
1990年 | 36篇 |
1989年 | 22篇 |
1988年 | 28篇 |
1987年 | 33篇 |
1986年 | 31篇 |
1985年 | 35篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 12篇 |
1978年 | 4篇 |
1977年 | 28篇 |
1976年 | 105篇 |
1975年 | 6篇 |
1972年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有2522条查询结果,搜索用时 15 毫秒
61.
Multi-Modal Dialog Scene Detection Using Hidden Markov Models for Content-Based Multimedia Indexing 总被引:1,自引:1,他引:0
A class of audio-visual data (fiction entertainment: movies, TV series) is segmented into scenes, which contain dialogs, using a novel hidden Markov model-based (HMM) method. Each shot is classified using both audio track (via classification of speech, silence and music) and visual content (face and location information). The result of this shot-based classification is an audio-visual token to be used by the HMM state diagram to achieve scene analysis. After simulations with circular and left-to-right HMM topologies, it is observed that both are performing very good with multi-modal inputs. Moreover, for circular topology, the comparisons between different training and observation sets show that audio and face information together gives the most consistent results among different observation sets. 相似文献
62.
IT outsourcing is a complex and opaque decision problem. Managers facing a decision about IT outsourcing have difficulty in
framing what needs to be thought about further in their discourses. Framing is one of the most crucial steps of human decision
making and needs to be assisted to better understand a decision situation. In this research, we examine a number of decision
primitives in the context of an IT outsourcing decision situation. We demonstrate how the decision primitives can be employed
so that managers can probe deep to better understand a decision situation and to establish a decision basis. In the organizational
setting, we exemplify the use of the decision primitives in relation to the perceived outsourcing implications for the managers
looking for assistance in accommodating a knowledge management perspective on IT outsourcing. Consequently, we induce insight
and a guideline on how to use knowledge management for effective outsourcing in one of the leading financial institutes in
Europe.
相似文献
Mehmet N. AydinEmail: |
63.
64.
Mehmet Emin Aydin 《Journal of Intelligent Manufacturing》2012,23(4):991-999
Coordination of multi agent systems remains as a problem since there is no prominent method suggests any universal solution. Metaheuristic agents are specific implementations of multi-agent systems, which imposes working together to solve optimisation problems using metaheuristic algorithms. An idea for coordinating metaheuristic agents borrowed from swarm intelligence is introduced in this paper. This swarm intelligence-based coordination framework has been implemented as swarms of simulated annealing agents collaborated with particle swarm optimization for multidimensional knapsack problem. A comparative performance analysis is also reported highlighting that the implementation has produced much better results than the previous works. 相似文献
65.
To investigate the feasibility of using tissue obtained from human tumor xenografts for in vitro screening of antineoplastic agents, we grew human tumor colony-forming units (CFU) in semisold agar from xenografts serially passaged in nude mice. Growth of human tumor CFU was accomplished from nine xenografts representing five different histological tumor types (ovarian carcinoma, adenocarcinoma of the colon, malignant melanoma, epidermoid carcinoma of the lung, and malignant astrocytoma). Cloning efficiency ranged from 0.04 to 0.1% and showed significant variability both between tumor types and between individual animals bearing the same type of xenograft. A high percentage of tumor CFU was in S phase [47 +/- 20% (S.D.)] as determined by the thymidine "suicide" technique. The number of tumor CFU observed increased linearly with increasing numbers of cells plated. In vitro drug sensitivity of the tumor CFU was assessed to Adriamycin, cis-platinum, and melphalan. The patterns of drug sensitivity were found to be reproducible and stable over a period of 9 months. Drug sensitivity curves to Adriamycin for five xenografts representing four tumor types showed complex patterns with plateau portions similar to those described for tumor CFU from primary tumors. The rank order of sensitivity of the tumors was compared to that of normal granulocyte-macrophage progenitors and, with the exception of the melanomas, was found to correlate well with clinical experience (order of sensitivity = colon less than ovary less than bone marrow). Growth of human tumor CFU from xenografts represents a reproducible and stable means for the study of the biology of tumor CFU and has potential applications as a means for screening new anticancer agents. 相似文献
66.
67.
Epidemiological evidence suggests that millet might play a role in the etiology of endemic goiter. Recently, we showed that a traditional fermentation procedure of two pearl millet (Pennisetum americanum L. Lecke) cultivars grown in Sudan modified their effects on the weight of the thyroid gland and thyroid hormone profile in rats. In the present study, we report that this fermentation procedure reduced the ash contents of millet by about 40% and removed considerable amounts of Mg (>50%), Zn (27-39%) and K (45%). Other minerals (Ca, Fe, Cu) were not affected. Feeding of one fermented cultivar resulted in significant reduction in bone Mg and Zn contents, whereas feeding of the other fermented cultivar resulted in reduction of bone Mg only. Dietary Mg intake and bone Mg contents correlated negatively with serum T3. Groups fed the millet diets had higher serum Se level compared to those fed wheat or casein diets and feeding of fermented millet resulted in a further increase in serum Se level. Thus our data indicate that in rats the enhanced effects of millet on the thyroid induced by fermentation is likely related to removal of minerals from millet and/or chemical transformation of the goitrogens contained in millet. 相似文献
68.
VN Balin IV Ga?voronski? AK Iordanishvili DIu Mada? VG Gololobov 《Canadian Metallurgical Quarterly》1994,73(2):7-11
Experimental studies making use of morphological and x-ray methods demonstrated that in comparison with control (filling of mandibular bone defects with blood clots) chonsuride, an animal polysaccharide, promoted earlier filling of postoperative bone cavities with connective tissue replacement of this tissue with coarse-fiber bone tissue. Secondary restructuring and mineralization of bone regenerate were enhanced as well. 相似文献
69.
The paper describes the accurate calibration of the camera transformation for a vision system consisting of a camera mounted on a robot. The calibration includes an analysis of the linearity of the camera. A knowledge of the camera transformation allows the three-dimensional position of the object points to be determined using triangulation. 相似文献
70.
A simulated annealing algorithm for multi-agent systems: a job-shop scheduling application 总被引:4,自引:1,他引:4
In this paper, a parallel implementation of the modular simulated annealing algorithm for classical job-shop scheduling is presented. The implementation is for a multi agent system running on the distributed resource machine, which is a novel, scalable, distributed virtual machine based on Java technology. The problems tackled are well known, difficult benchmarks, widely used to measure the efficiency of metaheuristics with respect to both the quality of the solutions and the central processing unit time. The empirical results obtained show that the method proposed is successful in comparison with a sequential version of modular simulated annealing algorithm and other methods described in the literature. 相似文献