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201.
The quest to improve performance forces designers to explore finer-grained multiprocessor machines. Ever increasing chip densities based on CMOS improvements fuel research in highly parallel chip multiprocessors with 100s of processing elements. With such increasing levels of parallelism, synchronization is set to become a major performance bottleneck and efficient support for synchronization an important design criterion. Previous research has shown that integrating support for fine-grained synchronization can have significant performance benefits compared to traditional coarse-grained synchronization. Not much progress has been made in supporting fine-grained synchronization transparently to processor nodes: a key reason perhaps why wide adoption has not followed.  相似文献   
202.
Basedon the success of the first Hungarian large capacity drinking water treatment ozonation plant of Budapest that was put into operation in 1984, a similar second plant was put into operation in 1988 in Debrecen with 150,000 inhabitants. This recently built plant solves taste and odor problems and water quality development of a surface water treatment plant with a capacity of 50,000 m3/day that is operative for a longer period of time. The experiences gained at the Budapest ozonizing plant were utilized during both planning and construction. Thus, for example, the method of ozone absorption had been modified.

The in-situ repair of the Frings turbines for ozone contacting placed at the Rackeve plant of the Budapest Waterworks will be introduced, as well as a concept of a newer kind of ozone mixing.  相似文献   

203.
To reveal the structural basis of the increased thermal stabilityof 3-isopropylmalate dehydrogenase (IPMDH) from Thermus thermophilus,an extreme thermophile, the homology-based structural modelof one mesophilic (Escherichia coli) counterpart, was constructed.Both IPMDHs are homodimeric proteins. We built a model of onesubunit using the 3-D structures of the Th.thermophilus IPMDHand the homologous E.coli isocitrate dehydrogenase. Energy minimizationand molecular dynamics simulated annealing were performed onthe dimer, including a surrounding solvation shell. No seriouserrors were detected in the refined model using the 3-D profilemethod. The resulting structure was scrutinized and comparedwith the structure of the Th.thermophilus IPMDH. Significantdifferences were found in the non-specific interactions includingthe hydrophobic effect. The model predicts a higher number ofion pairs in the Th.thermophilus than hi the E.coli enzyme.An increase was observed in the stabilities of -helical regionshi the thermophilic protein. The preliminary X-ray coordinatesof the E.coli IPMDH were received after the completion of thiswork, allowing an assessment of the model in terms of the X-raystructure. The comparison proved that most of the structuralfeatures underlying the stability differences between the twoenzymes were predicted correctly.  相似文献   
204.
Haptic feedback usually involves two types of stimulation forces: forces that address the touch sense and forces that address the kinesthetic perception. Touch forces have a low intensity and a complex structure since they reflect contact phenomena where friction plays an important role. Therefore, they are quite difficult to simulate. Virtual prototyping with haptic feedback should ideally involve both types of forces, but the integration of the touch feeling makes the simulator very complex. In this paper, we present a novel concept for virtual prototyping in which the touch interaction is separated from the kinesthetic force feedback. This is possible using a prototype that has a real part undertaking the touch interaction and a virtual part that simulate feedback for the kinesthetic forces. In this way, a full haptic interaction with the virtual prototype is established by means of a device that provides a realistic simulation of the product. In order to illustrate the concept, several experiments have been carried out for the case of specific subsystems of a car, which are particularly involved in the driver–car interaction: steering system, clutch pedal and the gearshift. A user test is described in the last part as well as the conclusions of the research.  相似文献   
205.
We present a data structure for maintaining the geodesic hull of a set of points (sites) in the presence of pairwise noncrossing line segments (barriers) that subdivide a bounding box into simply connected faces. For m barriers and n sites, our data structure has O((m+n)logn) size. It supports a mixed sequence of O(m) barrier insertions and O(n) site deletions in $O((m+n) \operatorname{polylog}(mn))$ total time, and answers analogues of standard convex hull queries in $O(\operatorname{polylog}(mn))$ time. Our data structure supports a generalization of the sweep line technique, in which the sweep wavefront is a simple closed polygonal curve, and it sweeps a set of n points in the plane by simple moves. We reduce the total time of supporting m online moves of a polygonal wavefront sweep algorithm from the naïve $O(m\sqrt{n} \operatorname{polylog}n)$ to $O((m+n) \operatorname{polylog}(mn))$ .  相似文献   
206.
207.
Urease thin films were produced by Matrix Assisted Pulsed Laser Evaporation (MAPLE) and Pulsed Laser Deposition from two types of targets: frozen water solutions of urease with different concentrations (1-10% m/v) and pure urease pellets. The fluence of the ablating KrF excimer laser was varied between 300 and 2200 mJ/cm2. Fourier transform infrared spectra of the deposited films showed no difference as compared to the original urease. Morphologic studies proved that the films consist of a smooth “base” layer with embedded micrometer-sized droplets. Absorption-coefficient measurements contradicted the traditional “absorptive matrix” model for MAPLE deposition. The laser energy was absorbed by urease clusters leading to a local heating-up and evaporation of the frozen matrix from the uppermost layer accompanied by the release of dissolved urease molecules. Significant enzymatic activity of urease was preserved only during matrix assisted transfer.  相似文献   
208.
We consider the problem of learning how to control a plant with nonlinear control characteristics and solving the path-planning problem at the same time. The solution is based on a path-planning model that designates a speed field to be tracked, the speed field being the gradient of the equilibrium solution of a diffusionlike process which is simulated on an artificial neural network by spreading activation. The relaxed diffusion field serves as the input to the interneurons which detect the strength of activity flow in between neighboring discretizing neurons. These neurons then emit the control signals to control neurons which are linear elements. The interneuron to control-neuron connections are trained by a variant of Hebb's rule during control. The proposed method, whose most attractive feature is that it integrates reactive path-planning and continuous motion control in a natural fashion, can be used for learning redundant control problems. © 1998 John Wiley & Sons, Inc. 15: 1–15, 1998  相似文献   
209.
Consumption of capsaicin or its nonpungent analogues, capsinoids has been reported to affect energy expenditure and fat oxidation, although available data are still controversial. The aim of the present study was to conduct a meta-analysis regarding the effects of these substances on energy expenditure and respiratory quotient, with special emphasis on the role of body mass index (BMI) of the participants. Medical databases were systematically searched for papers. Of the 627 trials identified, 9 provided results suitable to be included in analysis. Data analysis showed that after ingestion of capsaicin or capsinoids the energy expenditure increased (245 kJ/day, 58.56 kcal/day, p = 0.030) and the respiratory quotient decreased (by 0.216; p = 0.031) indicating a rise in fat oxidation. Studies with mean BMI of the participants below 25 kg/m2 failed to report any effect of capsaicin or capsinoids on the energy expenditure (p = 0.718) or on the respiratory quotient (p = 0.444), but studies with mean BMI exceeding 25 kg/m2 demonstrated an increase in energy expenditure (292 kJ/day, 69.79 kcal/day, p = 0.023) and a marked decrease in respiratory quotient (?0.257, p = 0.036). Our data clearly suggest that capsaicin or capsiate could be a new therapeutic approach in obesity promoting a negative energy balance and increased fat oxidation.  相似文献   
210.
Innovations in Systems and Software Engineering - When a person is concurrently interacting with different systems, the amount of cognitive resources required (cognitive load) could be too high and...  相似文献   
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