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1.
Electron emission from insulator-semiconductor interface in ZnS:Mn ac thin film electroluminescent (ACTFEL) display devices was investigated by studying the current and field waveforms. A new technique for measuring the interface electron energy distribution at insulator-semiconductor interfaces was developed. The technique involves the measurement of tunnel current transients and can be used to study the interface electron energy distribution between any insulator-semiconductor pair with which an ac thin film test structure can be fabricated. It was applied to a ZnS:Mn display device at two temperatures of 10 K and 300 K and to a metal interface device structure  相似文献   
2.
In this paper we present an identification algorithm for a class of continuous-time hybrid systems. In such systems, both continuous-time and discrete-time dynamics are involved. We apply the expectation-maximisation algorithm to obtain the maximum likelihood estimate of the parameters of a discrete-time model expressed in incremental form. The main advantage of this approach is that the continuous-time parameters can directly be recovered. The technique is particularly well suited to fast-sampling rates. As an application, we focus on a standard identification problem in power electronics. In this field, our proposed algorithm is of importance since accurate modelling of power converters is required in high- performance applications and for fault diagnosis. As an illustrative example, and to verify the performance of our proposed algorithm, we apply our results to a flying capacitor multicell converter.  相似文献   
3.
New polymerizable difunctional liquid crystals of monomers derived from 4‐hydroxybenzenethiol were synthesized, characterized, and photopolymerized by the formation of anisotropic films. These films were obtained by the irradiation of the monomers in the mesophase with UV light before they were macroscopically oriented in glasses treated on the surface with polyimide and uniaxially rubbed. The monomers showed smectic and nematic mesophases. The thin films, uniaxially oriented, were optically transparent. The orientation was verified by IR dichroism, which showed a preferential order of mesogens. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1812–1817, 2005  相似文献   
4.
Failure detection and consensus in the crash-recovery model   总被引:2,自引:0,他引:2  
Summary. We study the problems of failure detection and consensus in asynchronous systems in which processes may crash and recover, and links may lose messages. We first propose new failure detectors that are particularly suitable to the crash-recovery model. We next determine under what conditions stable storage is necessary to solve consensus in this model. Using the new failure detectors, we give two consensus algorithms that match these conditions: one requires stable storage and the other does not. Both algorithms tolerate link failures and are particularly efficient in the runs that are most likely in practice – those with no failures or failure detector mistakes. In such runs, consensus is achieved within time and with 4 n messages, where is the maximum message delay and n is the number of processes in the system. Received: May 1998 / Accepted: November 1999  相似文献   
5.
The problem of multicollinearity associated with the estimation of a functional logit model can be solved by using as predictor variables a set of functional principal components. The functional parameter estimated by functional principal component logit regression is often nonsmooth and then difficult to interpret. To solve this problem, different penalized spline estimations of the functional logit model are proposed in this paper. All of them are based on smoothed functional PCA and/or a discrete penalty in the log-likelihood criterion in terms of B-spline expansions of the sample curves and the functional parameter. The ability of these smoothing approaches to provide an accurate estimation of the functional parameter and their classification performance with respect to unpenalized functional PCA and LDA-PLS are evaluated via simulation and application to real data. Leave-one-out cross-validation and generalized cross-validation are adapted to select the smoothing parameter and the number of principal components or basis functions associated with the considered approaches.  相似文献   
6.
7.
Neural Computing and Applications - Understanding at microscopic level the generation of contents in an online social network (OSN) is highly desirable for an improved management of the OSN and the...  相似文献   
8.
A fast and reliable method for anthocyanin extraction and identification by HPLC‐DAD‐ESI/MS‐QTOF was used to analyse the anthocyanin composition of commercial red fruit juices (blackberry, redcurrant and pomegranate), purees (strawberry, cherry and raspberry) and concentrates (elderberry, blueberry and red grape). The anthocyanin profile of black carrot juice is also reported. The extraction and analysis method allowed us to detect and quantify a wide range of individual anthocyanins in a simple and rapid way. Pelargonidin‐3‐glucoside was detected in redcurrant for the first time and petunidin‐3‐galactoside quantified for the first time in blueberries. Considering the health benefits that have been associated with anthocyanin consumption, all these fruit and vegetables processed products could appear as a good source of this group of phytochemical compounds for their direct consumption or their use as ingredients for the design of new food product or food supplements.  相似文献   
9.
The authors developed and tested a 35-min psychoeducational program with the goal of increasing Spanish-speaking persons’ literacy of psychosis. The program uses popular cultural icons derived from music, art, and videos, as well as a mnemonic device—La CLAve (The Clue)—to increase (a) knowledge of psychosis, (b) efficacy beliefs that one can identify psychosis in others, (c) attributions to mental illness, and (d) professional help-seeking. Assessments were conducted before and after administering the program to both community residents (n = 57) and family caregivers of persons with schizophrenia (n = 38). For community residents, the authors observed increases across the 4 domains of symptom knowledge, efficacy beliefs, illness attributions, and recommended help-seeking. For caregivers, increases were observed in symptom knowledge and efficacy beliefs. La CLAve is a conceptually informed psychoeducational tool with a developing empirical base aimed at helping Spanish-speaking Latinos with serious mental illness obtain care in a timely manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Food aeration has become one of the fastest growing unit operations practiced in the food industry. Dispersed air (or other gases) provides an additional phase within the gel that may accommodate new textural and functional demands. This paper addresses the relationships between structural characteristics and fracture properties of gas-filled gelatin gels (GGG), and compare these properties with those of control gelatin gels (CGG). Three gases were used in the fabrication of GGG: air, nitrogen and helium. Experimental methods to determine density, gas hold-up, bubble sizes and bubble size distributions as well as fracture properties of GGG are presented. Increasing protein concentration produced higher density, lower gas hold-up and decreased polydispersity of bubbles due to its effect on increased solution viscosity. Type of gas affected density and gas hold-up due to the different diffusivities of gases and structures (bubble size, size distribution and number of bubbles per area) formed in GGG. Fracture values increased for both GGG and CGG with increasing protein concentration for the three gases used. GGG were weaker and less ductile than CGG, the decrease in stress and strain at fracture being between 70 and 80%, and 40 and 65%, respectively. A power law relationship (σf = 2.73 × 10−12ρG4.76) was found between the fracture stress and gel density for the three gases studied. This study shows that the presence of bubbles in gel-based food products results in unique textural properties conferred by the additional gaseous phase.  相似文献   
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