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71.
Yaman Ay?e; Mesman Judi; van IJzendoorn Marinus H.; Bakermans-Kranenburg Marian J. 《Canadian Metallurgical Quarterly》2010,24(2):208
We investigated the influence of parenting practices in the prediction of child physical aggression in 94 second-generation Turkish immigrant families with 2-year-old toddlers, and the moderating role of child temperament. In a longitudinal study we tested both a dual-risk model and a differential susceptibility model. Observational data were obtained for mothers’ positive parenting and authoritarian discipline, and maternal reports for child temperament and physical aggression. All measures were repeated 1 year later. Child temperament at age 2 years was a significant predictor of child aggression 1 year later. We found no main effects of positive parenting or of authoritarian discipline for the prediction of child aggression. However, we found support for the dual-risk hypothesis: Toddlers with difficult temperaments were more adversely affected by a lack of positive parenting than other children, but they did not benefit more from high levels of positive parenting than toddlers with more easy temperaments. We found no interaction effects with child temperament for authoritarian discipline. These findings provide support for the generalizability of the dual-risk model of parenting and temperament to non-Western immigrant families with young children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
In this paper, we propose and compare single- and multi-objective programming (MOP) approaches to the language model (LM) adaptation that require the optimization of a number of competing objectives. In LM adaptation, an adapted LM is found so that it is as close as possible to two independently trained LMs. The LM adaptation approach developed in this paper is based on reformulating the training objective of a maximum a posteriori (MAP) method as an MOP problem. We extract the individual at least partially conflicting objective functions, which yields a problem with four objectives for a bigram LM: The first two objectives are concerned with the best fit to the adaptation data while the remaining two objectives are concerned with the best prior information obtained from a general domain corpus. Solving this problem in an iterative manner such that each objective is optimized one after another with constraints on the rest, we obtain a target LM that is a log-linear interpolation of the component LMs. The LM weights are found such that all the (at least partially conflicting) objectives are optimized simultaneously. We compare the performance of the SOP- and MOP-based solutions. Our experimental results demonstrate that the ICO method achieves a better balance among the design objectives. Furthermore, the ICO method gives an improved system performance. 相似文献
73.
74.
In this work, we investigated the effect of electrodeposition of polypyrrole (PPy) films on two different self-assembled monolayers (SAMs) modified gold electrode for the electrochemical construction of ultramicroelectrode (UME). In order to obtain SAM modified surfaces, 4-mercapto-1-butanol and 11-mercaptoundecanoic acid were used. The effect of these two chains on pyrrole electropolymerization was compared. Electropolymerization of pyrrole on SAM modified Au electrode was carried out by using cyclic voltammetry (CV) and constant potential electrolysis. To investigate the UME formation, the obtained surfaces were tested in Fe(CN)63−/4− redox system. UMEs were characterized using scanning electron microscopy energy-dispersive X-ray spectroscopy, attenuated total reflectance fourier transform infrared spectroscopy and electrochemical impedance spectroscopy. The designed UME was applied as an immobilization matrix to entrap a redox protein, Hemoglobin (Hb), as a model. Direct electron transfer between this protein and the fabricated thiol modified PPy based UME was achieved, which is very challenging on bare electrode surfaces. With this study, a simple, low-cost and reproducible UME production way has been successfully accomplished and Hb modified UME is promising for different bioanalytical applications, for instance; cellular hydrogen peroxide or nitrite sensing. 相似文献
75.
Yaman S. Chin-Hui Lee 《IEEE transactions on audio, speech, and language processing》2008,16(4):779-789
We propose a multiobjective programming (MOP) framework for finding compromise solutions that are satisfactory for each of multiple competing performance criteria in a pattern classification task. The fundamental idea for our formulation of classifier learning, which we refer to as iterative constrained optimization (ICO), evolves around improving one objective while allowing the rest to degrade. This is achieved by the optimization of individual objectives with proper constraints on the remaining competing objectives. The constraint bounds are adjusted based on the objective functions obtained in the most recent iteration. An aggregated utility function is used to evaluate the acceptability of local changes in competing criteria, i.e., changes from one iteration to the next. Although many MOP approaches developed so far are formal and extensible to large number of competing objectives, their capabilities are examined only with two or three objectives. This is mainly because practical problems become significantly harder to manage when the number of objectives gets larger. We, however, illustrate the proposed framework in the context of automatic language identification (LID) of 12 languages and three dialects. This LID task requires the simultaneous minimization of the false-acceptance and false-rejection rates for each of the 15 languages/dialects, and, hence, is an MOP problem with a total of 30 competing objectives. In our experiments, we observed that the ICO-trained classifiers result in not only reduced error rates but also a good balance among the many competing objectives when compared to those classifiers that minimize an overall objective. We interpret our experimental findings as evidence for ICO offering a greater degree of freedom for classifier design. 相似文献
76.
77.
Jiangtao Sun Alvin Yung Boon Chong Siamak Tavakoli Guojin Feng Jamil Kanfoud Cem Selcuk 《Research in Nondestructive Evaluation》2019,30(4):205-230
An enhanced technique using image processing has been developed for automated ultrasonic inspection of composite materials, such as glass/carbon-fibre-reinforced polymer (GFRP or CFRP), to ascertain their structural healthiness. The proposed technique is capable of identifying the abnormality features buried in the composite by image filtering and segmentation applied to ultrasonic C-Scan images. This work presents results performed on two composite samples with simulated delamination defects. A local gating scheme is applied to raw A-Scan data for improved contrast between defective and healthy regions in the produced C-Scan image. In this test campaign, different filtering and thresholding algorithms are evaluated and compared in terms of their effectiveness on defect identification. The accuracies of less than 3 mm and 1.11 mm were attained for the defect size and depth, respectively. The results demonstrates the applicability of the proposed technique for accurate defect localization and characterization of composite materials. 相似文献
78.
Information axiom, one of two axioms of axiomatic design methodology which is proposed to improve a design, is used to select the best design among proposed designs. In the literature, there are a lot of studies related to using of information axiom for the solution of decision making problems. Moreover, applications of information axiom have been increasing day by day. However, calculation procedure of information axiom is not only incommodious but also difficult for decision makers. In this paper, a decision support system (DSS) based on fuzzy information axiom (FIA) is developed in order to make this decision procedure easy. The developed system consists of a knowledge base module including facts and rules, inference engine module including FIA and aggregation method, and a user interface module including entrance windows. The main aim of this study is to present a DSS tool to help the decision makers to solve their decision problems by modifying data-base of the program. In this paper, an application procedure will be presented based on the optimal selection of location for emergency service to illustrate the implementation procedure of the proposed model. 相似文献
79.
A grounded negative inductance emulator is proposed with full
independent control on both the inductance value and the
condition. It uses a single operational transresistance amplifier
(OTRA), a capacitor, and five resistors, two of which are for
independent control. Experimental results, which confirm the
theoretical analysis, are presented. 相似文献
80.