全文获取类型
收费全文 | 473篇 |
免费 | 22篇 |
专业分类
电工技术 | 18篇 |
化学工业 | 79篇 |
金属工艺 | 5篇 |
机械仪表 | 5篇 |
建筑科学 | 29篇 |
矿业工程 | 1篇 |
能源动力 | 10篇 |
轻工业 | 55篇 |
水利工程 | 3篇 |
无线电 | 21篇 |
一般工业技术 | 79篇 |
冶金工业 | 106篇 |
原子能技术 | 7篇 |
自动化技术 | 77篇 |
出版年
2022年 | 4篇 |
2021年 | 8篇 |
2019年 | 8篇 |
2018年 | 22篇 |
2017年 | 15篇 |
2016年 | 15篇 |
2015年 | 9篇 |
2014年 | 14篇 |
2013年 | 28篇 |
2012年 | 21篇 |
2011年 | 34篇 |
2010年 | 22篇 |
2009年 | 10篇 |
2008年 | 27篇 |
2007年 | 22篇 |
2006年 | 14篇 |
2005年 | 18篇 |
2004年 | 11篇 |
2003年 | 8篇 |
2002年 | 11篇 |
2001年 | 14篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1966年 | 3篇 |
1961年 | 3篇 |
1960年 | 2篇 |
1954年 | 2篇 |
排序方式: 共有495条查询结果,搜索用时 484 毫秒
1.
Anaerobic co-digestion of food waste and FOG with sewage sludge – realising its potential in Ireland
Olumide Wesley Awe Yaqian Zhao Ange Nzihou Doan Pham Minh Nathalie Lyczko 《The International journal of environmental studies》2018,75(3):496-517
The severe environmental pollution in many countries is caused by indiscriminate discharge of large quantities of food waste (FW), fat oil and grease (FOG) and sewage sludge (SS) to the environment. There are many possible treatment routes, but anaerobic digestion (AD) is now well accepted for treating several kinds of organic wastes. But AD of FW alone presents some operational challenges because of substrates and variability. Anaerobic co-digestion of two or more substrates is better than single substrate digestion. This can use a plant’s unused capacity, in line with the trend to renewable energy. Co-digestion technology, although well established in many European countries, is still in its infancy in Ireland. There are problems with different regulatory arrangements. They should be resolved. The paper reviews anaerobic co-digestion technology is reviewed, with special focus on possible application in Ireland. 相似文献
2.
Wesley P. Chan Hiroto Mizohana Xiangyu Chen Yasuto Shiigi Yoshiyuki Yamanoue Masaki Nagatsuka Masayuki Inaba 《野外机器人技术杂志》2019,36(1):17-33
The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition. 相似文献
3.
Multi-band power oscillation damping controller for power system supported by static VAR compensator
Electrical Engineering - Low-frequency electromechanical oscillations damping is powerfully crucial in power system operation. In order to fulfill this requirement, power oscillation damping (POD)... 相似文献
4.
Wesley W. Chu Ph.D. Ion T. leong Ph.D. Ricky K. Taira Ph.D. 《The VLDB Journal The International Journal on Very Large Data Bases》1994,3(4):445-477
We introduce a semantic data model to capture the hierarchical, spatial, temporal, and evolutionary semantics of images in pictorial databases. This model mimics the user's conceptual view of the image content, providing the framework and guidelines for preprocessing to extract image features. Based on the model constructs, a spatial evolutionary query language (SEQL), which provides direct image object manipulation capabilities, is presented. With semantic information captured in the model, spatial evolutionary queries are answered efficiently. Using an object-oriented platform, a prototype medical-image management system was implemented at UCLA to demonstrate the feasibility of the proposed approach. 相似文献
5.
D.A. Wesley 《Nuclear Engineering and Design》1993,142(2-3)
A proposed methodology and sample results from several plant investigations are presented for evaluating the expected pressure capacity of nuclear power plant components which could potentially be subjected to Interfacing Systems LOCA (ISLOCA) conditions. Included in this evaluation are tanks, heat exchangers, filters, pumps, valves and flanged connections for systems designed for relatively low-pressure, low temperature conditions, but which could possibly be exposed to reactor coolant conditions, either through human error or isolation valve failures. The probabilities of failure, as a function of internal pressure, are evaluated as well as the variabilities associated with them. Leak rates or leak areas are estimated for the controlling modes of failure. Pressure capacities for the pipes and vessels are evaluated using limit-state analyses for the various failure modes considered. The capacities are dependent on several factors, including the material properties, modeling assumptions, and the postulated failure criteria. The failure modes for gasketed-flange connections, valves and pumps do not lend themselves to evaluation by conventional structural mechanics techniques and evaluation must rely primarily on the results from ongoing gasket research test programs and available vendor information and test data. 相似文献
6.
Smaller cities seeking new economic development vehicles have embraced the growth of minor league sports. In an attempt to eliminate the threat of competition and maintain a sense of stability, four local governments purchased their respective minor league baseball franchise. This action may serve as a model for local governments that have invested heavily in professional sports as an economic development strategy. This study investigates the benefits of ownership in terms of stability for development, economic gain, and increased civic spirit. The study finds that publicly owned teams can be successfully used to anchor comprehensive plans for economic development, and that public ownership provides a way to pay the costs of the sports facilities and the debt service. There is little evidence to show that publicly owned teams increase civic spirit. However, this model presents some challenges that may prevent its widespread utilization. 相似文献
7.
Intelligent scheduling with tabu search: An application to jobs with linear delay penalties and sequence-dependent setup costs and times 总被引:3,自引:0,他引:3
In this article we study thetabu search (TS) method in an application for solving an important class of scheduling problems. Tabu search is characterized by integrating artificial intelligence and optimization principles, with particular emphasis on exploiting flexible memory structures, to yield a highly effective solution procedure. We first discuss the problem of minimizing the sum of the setup costs and linear delay penalties when N jobs, arriving at time zero, are to be scheduled for sequential processing on a continuously available machine. A prototype TS method is developed for this problem using the common approach of exchanging the position of two jobs to transform one schedule into another. A more powerful method is then developed that employs insert moves in combination with swap moves to search the solution space. This method and the best parameters found for it during the preliminary experimentation with the prototype procedure are used to obtain solutions to a more complex problem that considers setup times in addition to setup costs. In this case, our procedure succeeded in finding optimal solutions to all problems for which these solutions are known and a better solution to a larger problem for which optimizing procedures exceeded a specified time limit (branch and bound) or reached a memory overflow (branch and bound/dynamic programming) before normal termination. These experiments confirm not only the effectiveness but also the robustness of the TS method, in terms of the solution quality obtained with a common set of parameter choices for two related but different problems. 相似文献
8.
Heinz E Bille 《Coloration Technology》1987,103(12):427-434
Cotton continues to be a very widely used natural fibre. However, it becomes ever more difficult to define it exactly in chemical terms, because the variety and quantity of non-cellulosic constituents in the raw cotton are continually increasing in number and becoming more difficult to specify. The textile processor can only count on 75%, or at best 80%, being genuine cellulosic material; the remainder consists mainly of impurities that can seriously interfere with subsequent processes. Modem pretreatment processes take full account of the specific quality requirements, and naturally also the relevant cost factors (energy, effluent, processing costs). By these means the bleacher can now convert raw cotton into a chemically uniform and defined cellulosic textile substrate for the subsequent processes. In this form, either alone or in blends with synthetic fibres, it is accessible for dyeing, printing and finishing processes that can be readily controlled and reproduced. 相似文献
9.
As research in Computer-Supported Collaborative Learning (CSCL) expands its understanding of joint knowledge building, new perspectives on how social reality is constructed become necessary. Our research concentrates on the longitudinal or diachronic trajectories of Virtual Math Teams (VMT) at The Math Forum, an online community supporting mathematical inquiry. We investigate how these virtual teams constitute themselves while engaged in building collaborative knowledge. We describe as well, through the lens of positioning theory, the interactional activities that allow participants to situate themselves, others, and their collective knowledge resources over time. Our analysis suggests that positioning work is central to constructing a sustained problem space and illustrates how the configurations of positions and resources that co-participants put forward through interaction might change across a team’s trajectory. These changes constitute and are sensitive to the participants’ evolving reasoning routines and other forms of joint participation uniquely related knowledge building. In addition, we show that the VMT activity system affords participants a level of disciplinary engagement which is partly illustrated by active engagement in positioning work. Finally, we suggest that an interactional approach to roles and participation provides a fruitful framework for researchers, designers, and practitioners interested in understanding and creating engaging CSCL interactions. 相似文献
10.
Yuan X He X Guo H Guo P Kendall W Huang J Zhang Y 《IEEE transactions on visualization and computer graphics》2010,16(6):1413-1420
Over the past few years, large human populations around the world have been affected by an increase in significant seismic activities. For both conducting basic scientific research and for setting critical government policies, it is crucial to be able to explore and understand seismic and geographical information obtained through all scientific instruments. In this work, we present a visual analytics system that enables explorative visualization of seismic data together with satellite-based observational data, and introduce a suite of visual analytical tools. Seismic and satellite data are integrated temporally and spatially. Users can select temporal ;and spatial ranges to zoom in on specific seismic events, as well as to inspect changes both during and after the events. Tools for designing high dimensional transfer functions have been developed to enable efficient and intuitive comprehension of the multi-modal data. Spread-sheet style comparisons are used for data drill-down as well as presentation. Comparisons between distinct seismic events are also provided for characterizing event-wise differences. Our system has been designed for scalability in terms of data size, complexity (i.e. number of modalities), and varying form factors of display environments. 相似文献