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1.
History is bunk, declared Henry Ford; he wanted to sell new cars every year. For psychoanalysis history is not bunk; it is its very heart and guts. Like an individual or a nation, psychoanalysis lives its history and rediscovers it in every generation. Psychoanalytic pioneers, authors of new rallying cries and new theories, seem to think otherwise: History of psychoanalysis begins with them. The author suggests a different approach: to see the new as a historical continuity of the old. The advocates of the relational approach in psychoanalysis will be surprised to hear that Freud was a Sullivanian, even though--like the proverbial M. Jourdain who never heard the word prose--he never heard of the word interpersonal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The active component of the sex pheromone ofMatsucoccus josephi is (2E,6E,8E)-5,7-dimethyl-2,6,8-decatrien-4-one; the chemical is also a powerful kairomone of adult males and females of the bugElatophilus hebraicus the principal predator ofM. josephi. The presence of theZ isomer (2E,6Z,8E)-5,7-dimethyl-2,6,8-decatrien-4-one does not interfere with the attractancy of the activeE component forM. josephi males or the bug. Our results show a clear dose-response between trap catch ofM. josephi males andE. hebraicus. Conversely, increasing amounts of theZ isomer in the mixture did not affect the attraction of the scale insect males or the bug. The catch ofM. josephi males did not differ significantly among traps of different color, and was significantly higher with traps attached to the tree trunk than those suspended between trees. Comparison of the catch ofM. josephi among the three forests and between pine species suggests that the level of infestation ofPinus halepepsis andPinus brutia ssp.brutia is similar, despite the fact that the latter pine is resistant to the scale insect. Both sexes ofE. hebraicus were trapped in much lower numbers at the more infested sites. This may be related to interference with the activity ofE. hebraicus due to deterioration and drying of parts of the tree crowns and heavy colonization by generalist predators in injured trees.  相似文献   
3.
Detecting computer worms is a highly challenging task. We present a new approach that uses artificial neural networks (ANN) to detect the presence of computer worms based on measurements of computer behavior. We compare ANN to three other classification methods and show the advantages of ANN for detection of known worms. We then proceed to evaluate ANN’s ability to detect the presence of an unknown worm. As the measurement of a large number of system features may require significant computational resources, we evaluate three feature selection techniques. We show that, using only five features, one can detect an unknown worm with an average accuracy of 90%. We use a causal index analysis of our trained ANN to identify rules that explain the relationships between the selected features and the identity of each worm. Finally, we discuss the possible application of our approach to host-based intrusion detection systems.  相似文献   
4.
The influence of swirl on the shape of the Burke-Schumann reaction sheet in a straight cylindrical pipe is investigated by asymptotic and numerical means. Attention is confined to swirl levels that are near the critical value at which vortex breakdown occurs. A high-Reynolds-number, laminar, isothermal, low-Mach-number reacting flow is considered. An asymptotic analysis is developed to study the nonlinear interaction between near-critical swirl and mixture fraction distribution within the flow. It is first shown that leading-order perturbation of the velocity field from the columnar state, generated by the interaction of near-critical swirl and low viscosity, can be described by a nonlinear reduced-order model. This flow perturbation is computed, and then employed to determine the correction to the classical Burke-Schumann solution. Under lean conditions of reaction the reaction sheet becomes shorter and more compact as swirl is increased. For rich conditions of reaction, increasing swirl first causes the reaction-sheet length to decrease, and then increase after vortex breakdown has appeared. Numerical simulations of the flow and reaction-zone shape are substantiated by, and supplement, the asymptotic results.  相似文献   
5.
A differential improvement modification to Hybrid Genetic Algorithms is proposed. The general idea is to perform more extensive improvement algorithms on higher quality solutions. Our proposed Differential Improvement (DI) approach is of rather general character. It can be implemented in many different ways. The paradigm remains invariant and can be easily applied to a wider class of optimization problems. Moreover, the DI framework can also be used within other Hybrid metaheuristics like Hybrid Scatter Search algorithms, Particle Swarm Optimization, or Bee Colony Optimization techniques.  相似文献   
6.
The fabrication of cellulose-spider silk bio-nanocomposites comprised of cellulose nanocrystals (CNCs) and recombinant spider silk protein fused to a cellulose binding domain (CBD) is described. Silk-CBD successfully binds cellulose, and unlike recombinant silk alone, silk-CBD self-assembles into microfibrils even in the absence of CNCs. Silk-CBD-CNC composite sponges and films show changes in internal structure and CNC alignment related to the addition of silk-CBD. The silk-CBD sponges exhibit improved thermal and structural characteristics in comparison to control recombinant spider silk sponges. The glass transition temperature (Tg) of the silk-CBD sponge was higher than the control silk sponge and similar to native dragline spider silk fibers. Gel filtration analysis, dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and cryo-transmission electron microscopy (TEM) indicated that silk-CBD, but not the recombinant silk control, formed a nematic liquid crystalline phase similar to that observed in native spider silk during the silk spinning process. Silk-CBD microfibrils spontaneously formed in solution upon ultrasonication. We suggest a model for silk-CBD assembly that implicates CBD in the central role of driving the dimerization of spider silk monomers, a process essential to the molecular assembly of spider-silk nanofibers and silk-CNC composites.  相似文献   
7.
The absorption of water vapor by propellants based on hydroxy-terminated polybutadiene and an isocyanate from atmospheres of increasing relative humidities, and the swelling index of the propellant which had absorbed various proportions of water, were measured in an attempt to establish the extent of hydrolytic damage. The method was found incapable of assessing such damage, but it was shown that there was no measurable absorption of vapor below 92 percent relative humidity (RH). The MEK/polymer and toluene/polymer interaction parameters were determined.  相似文献   
8.
In order to find out whether or not a cross-weave ceramic composite, graphite fibre/SiC matrix, would be prone to fatigue failure, tests in pulsating tension and pulsating compression have been carried out with the weave oriented in the 0/90 configuration. Both types of testing (at fairly high fractions of the ultimate monotonic failure load) cause creep strain, which is frequency dependent in tension, and ultimately complete failure can occur. Damage in pulsating tension is found to consist of cumulative microcracking and spalling, with the final failure mechanism broadly similar to that in monotonic deformation. Damage in pulsating compression appears dominated by delamination.  相似文献   
9.
It has been observed by many researchers that systolic arrays are very suitable for certain high-speed computations. Using a formal methodology, we present a design for a single simple programmable linear systolic array capable of solving large numbers of problems drawn from a variety of applications. The methodology is applicable to problems solvable by sequential algorithms that can be specified as nested for-loops of arbitrary depth. The algorithms of this form that can be computed on the array presented in this paper include 25 algorithms dealing with signal and image processing, algebraic computations, matrix arithmetic, pattern matching, database operations, sorting, and transitive closure. Assuming bounded I/O, for 18 of those algorithms the time and storage complexities are optimal, and therefore no improvement can be expected by using dedicated special-purpose linear systolic arrays designed for individual algorithms. We also describe another design which, using a sufficient large local memory and allowing data to be preloaded and unloaded, has an optimal processor/time product.An earlier version of this paper was presented at Supercomputing '88.This work was partially supported by ONR under the contract N00014-85-K-0046 and by NSF under Grant Number CCR-8906949.  相似文献   
10.
We introduce linear control systems, termed chattering systems, which model instantaneous oscillations in the control parameters. Such systems serve as a limit case of systems with rapidly oscillating control parameters, which can be analyzed as perturbations from the chattering model. Several optimization and regulation problems for chattering systems are examined, along with the robustness property: the possibility of employing the solutions of the chattering case in the rapidly oscillating approximations. The theory is demonstrated on an example of an armature-controlled dc motor.  相似文献   
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