全文获取类型
收费全文 | 609篇 |
免费 | 4篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 14篇 |
化学工业 | 107篇 |
金属工艺 | 26篇 |
机械仪表 | 5篇 |
建筑科学 | 14篇 |
矿业工程 | 1篇 |
能源动力 | 17篇 |
轻工业 | 49篇 |
水利工程 | 13篇 |
无线电 | 27篇 |
一般工业技术 | 95篇 |
冶金工业 | 96篇 |
原子能技术 | 6篇 |
自动化技术 | 145篇 |
出版年
2024年 | 6篇 |
2023年 | 4篇 |
2022年 | 12篇 |
2021年 | 19篇 |
2020年 | 12篇 |
2019年 | 20篇 |
2018年 | 19篇 |
2017年 | 12篇 |
2016年 | 20篇 |
2015年 | 16篇 |
2014年 | 23篇 |
2013年 | 39篇 |
2012年 | 34篇 |
2011年 | 32篇 |
2010年 | 36篇 |
2009年 | 22篇 |
2008年 | 25篇 |
2007年 | 34篇 |
2006年 | 18篇 |
2005年 | 15篇 |
2004年 | 18篇 |
2003年 | 15篇 |
2002年 | 7篇 |
2001年 | 17篇 |
2000年 | 8篇 |
1999年 | 10篇 |
1998年 | 19篇 |
1997年 | 17篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 9篇 |
1993年 | 10篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
排序方式: 共有615条查询结果,搜索用时 0 毫秒
101.
The optimization problem of structural systems with imprecise properties on the basis of a possibilistic approach is considered. System imprecisions are defined by fuzzy numbers and characterized by membership functions. A methodology for the efficient solution of the optimization process is presented. A two-step method is used to include the imprecision within the optimization, where high quality approximations are used for the evaluation of structural responses. The approximations are constructed using concepts of intermediate response quantities and intermediate variables. The approach is basically an algebraic process which can be implemented very efficiently for the optimal design of general structural systems with imprecise parameters. The method provides more information to the designer than is available using conventional design tools. The effectiveness of the methodology and the interpretation of the results are illustrated by the solution of two example problems. 相似文献
102.
Hector Hernandez Delgadillo Benoit Kern Richard Loendersloot Doekle Yntema Remko Akkerman 《Journal of Nondestructive Evaluation》2018,37(4):79
In this research, ultrasonic pulse echo measurements are used to quantify through thickness chemical degradation in thin mortar specimens. The degradation level is predicted using the time of travel of the acoustic wave through the thickness of the structure. The front and back wall interaction reflections are used to obtain additional information from very early stage degradation. The pulse-velocity of sound waves as a function of the thickness of the layers within the structure is described. With knowledge of the pulse-velocity in pristine and fully degraded conditions, it is possible to determine the complete range of degradation length over the layer thickness. The method is applicable for leaching of calcium and acidic attack. The acoustic measurements were verified with destructive testing. The correlation between the acoustic and non-acoustic experiments agree with the described pulse-velocity and degraded depth function. The method based on ultrasonic measurements can be implemented in other thin-layered structures. 相似文献
103.
Jose Portillo-Portillo Roberto Leyva Victor Sanchez Gabriel Sanchez-Perez Hector Perez-Meana Jesus Olivares-Mercado Karina Toscano-Medina Mariko Nakano-Miyatake 《Applied Intelligence》2018,48(5):1200-1217
This paper proposes a view-invariant gait recognition algorithm, which builds a unique view invariant model taking advantage of the dimensionality reduction provided by the Direct Linear Discriminant Analysis (DLDA). Proposed scheme is able to reduce the under-sampling problem (USP) that appears usually when the number of training samples is much smaller than the dimension of the feature space. Proposed approach uses the Gait Energy Images (GEIs) and DLDA to create a view invariant model that is able to determine with high accuracy the identity of the person under analysis independently of incoming angles. Evaluation results show that the proposed scheme provides a recognition performance quite independent of the view angles and higher accuracy compared with other previously proposed gait recognition methods, in terms of computational complexity and recognition accuracy. 相似文献
104.
Summary. In a multi-party transaction (also called a distributed commerce transaction) agents face risks from dealing with untrusted
agents. These risks are compounded in the face of deadlines, e.g., an agent may fail to deliver purchased goods by the time
the goods are needed. We characterize the risks, and present a distributed algorithm that mitigates these risks, by using
pairwise exchanges and trusted intermediaries. The algorithm generates a safe sequence of actions that completes a commerce
transaction without risk, if such a sequence exists. We show that the algorithm is sound (produces only safe multi-agent action
sequences) and complete (finds a safe sequence whenever one exists). The initial restriction of guaranteeing safety even when
none of the principals trusts another can be relaxed in some cases, so we show how to handle principals that do trust each
other and interact directly rather than through a trusted intermediary.
Received: September 1997 / Accepted: December 1998 相似文献
105.
Marcos Rodriguez Pascual Daniela Trambitas Elisa Saez Calvo Herman Kramer Geert-jan Witkamp 《Chemical Engineering Research and Design》2010
A crystallizer was built and a procedure developed to accurately measure the eutectic solubility lines where ice and salt coexist in equilibrium with the solution, for potential application of Eutectic Freeze Crystallization. The eutectic solubility lines of the ternary system NaHCO3–Na2CO3–H2O were determined experimentally and calculated with the extended UNIQUAC model. The extended UNIQUAC model describes the experimental data quite well. Anhydrous NaHCO3 and Na2CO3·10H2O were the only two types of crystals present in equilibrium with ice crystals in the ternary system. At the quadruple point NaHCO3 and Na2CO3·10H2O are in equilibrium with a solution of about 4.34 wt% of Na2CO3 and 4.77 wt% of NaHCO3 at −3.32 °C. The anhydrous NaHCO3 crystals were needle shaped with lengths between 5 and 10 μm, that were agglomerated into particles of about 100–300 μm, while the Na2CO3·10H2O crystals were hexagonally shaped with sizes between 100 and 500 μm. 相似文献
106.
Hector Mark A.; Davis Kathleen L.; Denton Elizabeth A.; Hayes Theodore W.; Patton-Crowder Carolyn; Hinkle W. Keith 《Canadian Metallurgical Quarterly》1981,28(1):53
50 graduate students were randomly divided into 5 groups that were exposed to different kinds of videotaped counselor training procedures. The group of main interest was exposed to a training procedure that enabled the Ss 1st to verbally practice responding to client negative affect and then to observe a model counselor's response. When these Ss counseled either angry or depressed role-playing clients, they responded more consistently to client feelings than did Ss exposed to other training procedures. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Pedro Isasi David Quintana and Yago Saez Asuncion Mochon 《Computational Intelligence》2007,23(2):111-116
This article introduces some relevant research works on computational intelligence applied to finance and economics. The objective is to offer an appropriate context and a starting point for those who are new to computational intelligence in finance and economics and to give an overview of the most recent works. A classification with five different main areas is presented. Those areas are related with different applications of the most modern computational intelligence techniques showing a new perspective for approaching finance and economics problems. Each research area is described with several works and applications. Finally, a review of the research works selected for this special issue is given. 相似文献
108.
Shapiro Steven; Lesperance Yves; Levesque Hector J. 《Journal of Logic and Computation》2007,17(5):983-1018
Although there has been much discussion of belief change (e.g.[4, 21]), goal change has not received much attention. In thispaper, we propose a method for goal change in the frameworkof Reiter's; [12] theory of action in the situation calculus[8, 10], and investigate its properties. We extend the frameworkdeveloped by Shapiro et al. [17] and Shapiro and Lespérance[16], where goals and goal expansion were modelled, but goalcontraction was not. 相似文献
109.
Michela Baccini Annibale Biggeri Corrado Lagazio Marc Saez 《Computational statistics & data analysis》2007,51(9):4324-4336
Generalized additive models (GAMs) have become the standard tool for the analysis of short-term effects of air pollution on human health. Usually, the confounding effect of seasonality and long-term trend is described by flexible parametric or non-parametric functions of calendar time. Two different modeling strategies, i.e. GAM with penalized regression splines and GAM with regression splines, were compared by means of a simulation study, addressing attention to the inference on air pollutant effect. Simulation results indicated that GAM with regression splines provides negligibly biased estimates of air pollutant effect and it is robust to misspecification of the degrees of freedom of the spline. GAM with penalized regression splines requires a certain amount of undersmoothing in order to reduce the bias of the estimates and to improve the coverage of confidence intervals. These findings agree with asymptotic results developed in the context of partially splined models. 相似文献
110.
Bankruptcy prediction has long time been an active research field in finance. One of the main approaches to this issue is
dealing with it as a classification problem. Among the range of instruments available, we focus our attention on the Evolutionary
Nearest Neighbor Classifier (ENPC). In this work we assess the performance of the ENPC comparing it to six alternatives. The
results suggest that this algorithm might be considered a good choice. 相似文献