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91.
One of the main reasons preventing a wide application of eHome systems in practice is the effort needed to combine all appliances, necessary controller and infrastructure components to benefit from derived value-added services. The properties, dependencies, locations, and installation conditions have to be properly specified for this composition and its deployment. Due to the great variance in services and eHome configurations there is a need for tool support for eHome systems. In this paper we address the software development issues of such tools. In our approach we base the software development on graph rewriting language techniques. Based on our experience, we consider this approach as a possibility to improve the productivity of the eHome system tool development. With the aid of Fujaba, we created a model capable of specifying functions, devices, environments, and value-added services. Furthermore, we used Fujaba to create the activities as graph rewriting rules for model modifications. To apply the model and to carry out the actual specification for a particular eHome and particular appliances we generated the eHomeSpecificator tool from the model and its activities. This tool can serve as a base for a wider range of tools supporting eHome systems.  相似文献   
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93.
In general, plates and shells out of composite laminates are more susceptible to transverse shear than those out of homogeneous isotropic material. By means of different shear flexible theories the effect on buckling and postbuckling behaviour is studied. It turns out that there is a rather limited range of plates where the transverse shear is of considerable influence. Results obtained with Mindlin- or Reissner-type theories prove almost as adequate as those obtained with Reddy's theory. For the buckling analysis of shells the Kirchhoff–Love theory is precise enough. Snap-through buckling and imperfection sensitivity appear in composite shells, too, especially if they are optimized with respect to high bifurcation buckling loads.  相似文献   
94.
The serum lipoprotein(a) [Lp(a)] level is a known risk factor for arteriosclerotic coronary artery disease. However, its association with restenosis after percutaneous transluminal coronary angioplasty (PTCA) is controversial. We hypothesized that the Lp(a) level is a significant risk factor for restenosis after angioplasty through a pathophysiological mechanism leading to excess thrombin generation or inhibition of fibrinolysis. We designed a prospective study of the relation of Lp(a) to outcome after PTCA, in which we measured selected laboratory variables at entry and collected clinical, procedural, lesion-related, and outcome data pertaining to restenosis. Restenosis was defined as >50% stenosis of the target lesion by angiography or as ischemia in the target vessel distribution by radionuclide-perfusion scan. Before the patients underwent PTCA, blood was obtained by venipuncture for measurement of Lp(a), total cholesterol, thrombin-antithrombin (TAT) complex, alpha2-antiplasmin-plasmin (APP) complex, and plasminogen activator inhibitor-1 (PAI-1). Evaluable outcome data were obtained on 162 subjects, who form the basis of this report. Restenosis occurred in 61 subjects (38%). The Lp(a) level was not correlated significantly with TAT, APP, PAI-1, or the TAT-APP ratio. Levels of TAT, APP, and PAI-1 were not statistically different in the patients with versus those without restenosis. The median ratio of TAT to APP was 2-fold higher in the restenosis group, and this difference approached statistical significance (P=0.07). Univariate analysis was performed for the association of clinical, lesion-related, and procedural risk factors with restenosis. Lp(a) levels did not differ significantly in the restenosis versus no-restenosis group, whether assessed categorically (>25 mg/dL versus <25 mg/dL) or as a continuous variable by Mann-Whitney U test. The number of lesions dilated and the lack of family history of premature heart disease were significantly associated with restenosis (P=0.002 and P=0.008, respectively). A history of diabetes mellitus was of borderline significance (P=0.055). By multiple logistic regression analysis, the number of lesions dilated was the only variable significantly associated with restenosis (P=0.03). We conclude that the number of lesions dilated during PTCA is a significant risk factor for restenosis, whereas the serum Lp(a) level was not a significant risk factor for restenosis in our patient population. The TAT to APP ratio merits further study as a possible risk factor for restenosis.  相似文献   
95.
Using new nonisotopic and isotopic methods, we showed previously that fatty acid synthesis was markedly stimulated in weight-stable normal volunteers by a very-low-fat formula diet with 10% of energy as fat and 75% as short glucose polymers. In this study, we determined whether fatty acid synthesis was equally stimulated by a very-low-fat solid diet made with foods consumed typically. Four normal volunteers consumed the same very-low-fat formula diet for 25 d and then an isoenergetic solid food diet with 10% of energy as fat and 75% as starch, simple sugars, and fiber for 25 d. To measure fatty acid synthesis, the fatty acid compositions of the diets were matched to the composition of each subject's adipose tissue and compared with the composition of VLDL-triacylglycerol. In all subjects, the large increases in newly formed palmitate and decreases in linoleate in VLDL-triacylglycerol were quickly reversed by the solid food diet, and the fraction of de novo synthesized fatty acids in fasting VLDL-triacylglycerol decreased from 30-54% to 0-1%. In a second group of subjects, the stimulation of fatty acid synthesis by the formula diet with 75% glucose polymers was similarly reduced by a formula diet with amounts of fat, starch, and sugar chosen to mimic those of the solid food diet, but persisted after the addition of fiber or a diet with 75% sugar. In conclusion, an increase in fatty acid synthesis and palmitaterich, linoleate-poor VLDL-triacylglycerol induced by very-low-fat, high-sugar diets may be reduced by the substitution of dietary starch for sugar with potentially beneficial effects on cardiovascular health.  相似文献   
96.
97.
Current CAD tools are not able to support the conceptual design phase, and none of them provides a consistency analysis for sketches produced by architects. This phase is fundamental and crucial for the whole design and construction process of a building. To give architects a better support, we developed a CAD tool for conceptual design and a knowledge specification tool. The knowledge is specific to one class of buildings and it can be reused. Based on a dynamic and domain-specific knowledge ontology, different types of design rules formalize this knowledge in a graph-based form. An expressive visual language provides a user-friendly, human readable representation. Finally, a consistency analysis tool enables conceptual designs to be checked against this formal conceptual knowledge.In this article, we concentrate on the knowledge specification part. For that, we introduce the concepts and usage of a novel visual language and describe its semantics. To demonstrate the usability of our approach, two graph-based visual tools for knowledge specification and conceptual design are explained.  相似文献   
98.
This article presents experimental evidence on forced choices between inferior alternatives. In asking subjects to make trade offs between an experimentally induced cold-pressor pain of different durations and paying money to avoid the administration of pain, we try to shed some light on the questions: (a) are there any gender differences in elicited willingness to pay (WTP) values for pain; (b) when present, is differing WTP across genders better explained by measures of risk-aversion or measures of loss-aversion; and (c) we further investigate whether there are variations in hypothetically elicited WTP values (hypothetical pain and hypothetical money) and WTP values elicited when subjects face real consequences (both real pain and real money). Our results confirmed the hypothesis of significant gender differences in elicited WTP values in both the hypothetical and real groups. We also found some evidence of significant differences due to the treatment. Subjects who experienced the cold-pressor pain only once (hypothetical group) exhibited on average greater WTP compared with subjects who experienced the cold-pressor pain multiple times (real group). Females, however, stated lower WTP in the real treatment while for males the effect was in the opposite direction. Moreover, we found risk attitudes to be significantly associated with WTP while loss-aversion not. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
99.
 A method for the analysis of reducing sugar enantiomers in beverages using capillary zone electrophoresis is presented. Based on previous results, a resolution of all aldo-hexoses, -pentoses, -tetroses and trioses is achieved. Additional separation of uronic acids, deoxy and amino sugars in different buffer systems is demonstrated. Derivatives of sugar enantiomers change their migration order if derivatized with the phenylethylamine enantiomer. Thus, the use of a chiral derivatizing agent leads to simpler peak validation and opens new opportunities for the development of new applications. Screening of pharmaceutical drugs or food for rare sugar enantiomers with a detection limit of 25 fmol (5 μM) is feasible. Adaptation of the general method to wine, juice and instant coffee is demonstrated. The aldose, uronic acid and deoxy aldose enantiomer composition of the presented beverages is obtained in a single run. Received: 20 April 1998 / Revised version: 15 June 1998  相似文献   
100.
We study the role of connectivity of communication networks in private computations under information theoretical settings in the honest-but-curious model. We show that some functions can be 1-privately computed even if the underlying network is 1-connected but not 2-connected. Then we give a complete characterisation of non-degenerate functions that can be 1-privately computed on non-2-connected networks. Furthermore, we present a technique for simulating 1-private protocols that work on arbitrary (complete) networks on k-connected networks. For this simulation, at most additional random bits are needed, where L is the number of bits exchanged in the original protocol and n is the number of players. Finally, we give matching lower and upper bounds for the number of random bits needed to compute the parity function on k-connected networks 1-privately, namely random bits for networks consisting of n players.  相似文献   
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