全文获取类型
收费全文 | 4934篇 |
免费 | 103篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 46篇 |
综合类 | 2篇 |
化学工业 | 921篇 |
金属工艺 | 65篇 |
机械仪表 | 102篇 |
建筑科学 | 217篇 |
矿业工程 | 16篇 |
能源动力 | 142篇 |
轻工业 | 351篇 |
水利工程 | 48篇 |
石油天然气 | 31篇 |
武器工业 | 1篇 |
无线电 | 282篇 |
一般工业技术 | 735篇 |
冶金工业 | 1392篇 |
原子能技术 | 53篇 |
自动化技术 | 639篇 |
出版年
2021年 | 43篇 |
2020年 | 38篇 |
2019年 | 56篇 |
2018年 | 62篇 |
2017年 | 67篇 |
2016年 | 57篇 |
2015年 | 58篇 |
2014年 | 75篇 |
2013年 | 275篇 |
2012年 | 172篇 |
2011年 | 240篇 |
2010年 | 145篇 |
2009年 | 184篇 |
2008年 | 221篇 |
2007年 | 212篇 |
2006年 | 214篇 |
2005年 | 188篇 |
2004年 | 148篇 |
2003年 | 141篇 |
2002年 | 125篇 |
2001年 | 76篇 |
2000年 | 102篇 |
1999年 | 89篇 |
1998年 | 87篇 |
1997年 | 81篇 |
1996年 | 77篇 |
1995年 | 88篇 |
1994年 | 82篇 |
1993年 | 93篇 |
1992年 | 91篇 |
1991年 | 65篇 |
1990年 | 70篇 |
1989年 | 67篇 |
1988年 | 63篇 |
1987年 | 83篇 |
1986年 | 80篇 |
1985年 | 88篇 |
1984年 | 71篇 |
1983年 | 71篇 |
1982年 | 74篇 |
1981年 | 67篇 |
1980年 | 50篇 |
1979年 | 52篇 |
1978年 | 62篇 |
1977年 | 55篇 |
1976年 | 50篇 |
1975年 | 57篇 |
1974年 | 38篇 |
1973年 | 51篇 |
1972年 | 35篇 |
排序方式: 共有5043条查询结果,搜索用时 375 毫秒
81.
This paper proposes a model for dynamic pricing that combines knowledge of production capacity and existing commitments, reasoning about uncertainty and learning of market conditions in an attempt to optimise expected profits. In particular, the market conditions are represented as a set of probabilities over the success rate of product prices, and those prices are learned online as the market develops. The dynamic pricing model is integrated into a real-time supply chain management agent using the Trading Agent Competition Supply Chain Management game as a test framework. We evaluate the agent experimentally in competition with other supply chain agents, and demonstrate the benefits of incorporating more market data into the dynamic pricing mechanism. 相似文献
82.
We performed an empirical investigation of factors affecting an individual's decision to adopt anti-spyware software. Our results suggested that an individual's attitude, subjective norm, perceived behavioral control, and denial of responsibility significantly affected anti-spyware adoption intention. Also, relative advantage and compatibility showed a significant effect on attitude, visibility, and image on subjective norm, and trialability, self-efficacy, and computing capacity on perceived behavioral control. Interestingly, moral obligation, ease of use, and perceived cost were not as significant as was originally expected. 相似文献
83.
An investigation showing the performance of compact long period grating (LPG) pairs under demanding experimental conditions, making comparisons with the use of single LPGs for the simultaneous measurement of strain and temperature is presented. In this work, a LPG pair (LPGP) sensor comprising two weak (2.5 dB each) LPGs, 13 mm apart, was compared against the performance of two single LPG sensors (LPG1 & LPG2) with coupling strengths of 2.5 dB and 12.5 dB, respectively. All the LPG sensors used were subjected to extreme conditions arising from the fabrication, by choosing a high amplitude mask period with short physical length LPGs, and the high temperature annealing processes. In addition, a low resolution detection instrument was used to capture the spectra under study. Results have shown that the LPGP is 40 times better than the first single LPG used (LPG1) and three times better than the second LPG (LPG2). Using the error analysis methodology of Brady et al., the temperature and strain errors due to the uncertainty of the wavelength measurement for each of the LPG1, LPG2, and LPGP were compared with the typical performance of various fibre Bragg grating (FBG)-based sensor schemes under similar testing conditions. It was found that LPGPs offer the best performance especially when using low resolution detection instrumentation. 相似文献
84.
The Companion cognitive architecture supports experiments in achieving human-level intelligence. This article describes seven key design goals of Companions, relating them to properties of human reasoning and learning, and to engineering concerns raised by attempting to build large-scale cognitive systems. We summarize our experiences with Companions in two domains: test taking and game playing. 相似文献
85.
Kenneth Kunen 《Journal of Automated Reasoning》1995,15(2):217-235
We use the Boyer-Moore Prover, Nqthm, to verify the Paris-Harrington version of Ramsey's theorem. The proof we verify is a modification of the one given by Ketonen and Solovay. The theorem is not provable in Peano Arithmetic, and one key step in the proof requires 0 induction.Author supported by NSF Grant DMS-9100665. 相似文献
86.
Lee Connie M. S. Fong Kenneth N. K. Mok Maggie M. Y. Lam M. K. Kung Y. Chan Paven P. W. Ma Maggie K. M. Lui S. L. Kwan Lorraine P. Y. Chu W. L. Hui P. C. Yau Christina S. F. Kwan Ivan W. L. Chan Kelsey Y. M. Chan T. M. 《Virtual Reality》2023,27(3):1571-1583
Virtual Reality - Cognitive impairment is not uncommon in patients with end-stage renal disease and can make it more difficult for these patients to carry out peritoneal dialysis (PD) on their own.... 相似文献
87.
Harry McCarthy Abigail Koay Michael Dawson Kenneth B. Kent Panos Patros 《Software》2022,52(1):172-193
Tablets, smartphones, and wearables have limited resources. Applications on these devices employ a graphical user interface (GUI) for interaction with users. Language runtimes for GUIs employ dynamic memory management using garbage collection (GC). However, GC policies and algorithms are designed for data centers and cloud computing, but they are not necessarily ideal for resource-constrained embedded devices. In this article, we present GUI GC, a JavaFX GUI benchmark, which we use to compare the performance of the four GC policies of the Eclipse OpenJ9 Java runtime on a resource-constrained environment. Overall, our experiments suggest that the default policy Gencon registered significantly lower execution times than its counterparts. The region-based policy, Balanced, did not fully utilize blocking times; thus, using GUI GC, we conducted experiments with explicit GC invocations that measured significant improvements of up to 13.22% when multiple CPUs were available. Furthermore, we created a second version of GUI GC that expands on the number of controllable load-stressing dimensions; we conducted a large number of randomly configured experiments to quantify the performance effect that each knob has. Finally, we analyzed our dataset to derive suitable knob configurations for desired runtime, GC, and hardware stress levels. 相似文献
88.
89.
90.