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41.
We have designed a colorimetric conjugated polymer (PDMAp) for selective ATP sensing based on poly(2,5-dimethoxyaniline) bearing phthalimide which can form hydrogen bonds with adenine. PDMAp have been synthesized via chemical oxidative polymerization with CSA and DDQ and dedoping with an aqueous ammonia solution. PDMAp was displayed to signal the colorimetric selective detection for ATP over various nucleotides such as ADP, AMP, CTP, TTP, and GTP in DMSO–water (9:1, v/v) mixture. The absorption spectral change can be attributed to a doping process of ATP to PDMAp through hydrogen bonds between phthalimide and adenine as well as electrostatic interactions between the phosphate group of ATP and the backbone of PDMAp.  相似文献   
42.
The application of superconductivity technology to electric power apparatus is very important from the viewpoint of energy saving. Especially, the superconducting generators using superconductors as the field windings have many merits compared with conventional generators. Super-GM has been researching and developing 70-MW-class model machines since FY 1988 for a scheduled period of eight years, aiming at a 200-MW-class superconducting generator. This paper describes the basic specifications and designs of 70-MW-class superconducting generators by Super-GM and also describes the propriety of these basic specifications and designs.  相似文献   
43.
A continuous vacuum dryer for energy saving has been developed in order to produce dried foods without heat denaturation in the products. This drying method is suitable for heat sensitive I and highly viscous foods and can dry to 1 to 4% in moisture content with good quality at around 40°C in product temperature andin 5 -10 min a drying time. Feed material with high viscosity has to I have uniform distribution on the belt in the vacuum chamber to I keep a constant drying for which a special feed nozzle has been developed after considerabl~ testing. Heat transfer on the wet material in the dryer has occurred by both conduction and radiation because of the design so that the thermal efficiency in  相似文献   
44.
In order to prepare phosphoric acid resins (RGPs) with large cation exchange capacities, effects of porosity and cross-linking of the precursory poly(glycidyl methacrylate-co-divinylbenzene) beads on their functionalization with phosphoric acid were studied. Two series of precursory copolymers were prepared: one was prepared by changing the amount of divinylbenzene (1–25 mol %) but by fixing that of isobutyl acetate (porogen) at 140 vol % per monomer mixture; the other by changing the amount of the porogen (40–160 vol %) but by fixing that of the cross-linker at 10 mol %. It was clarified that porosity of the precursors plays an important role in the functionalization. Highly porous precursors were functionalized with high efficiency; for example, even the precursors containing 10 mol % of divinylbenzene resulted in RGPs having cation exchange capacities as large as 6–7 meq/g, so long as BET specific surface areas of the precursors were greater than ca. 30 m2/g. The selectivity study has revealed that RGP exhibits the characteristic metal ion selectivity. Lithium ion was adsorbed in preference to sodium and potassium ions; and so-called hard Lewis acid cations, such as uranyl, ferric, and aluminum ions, are adsorbed even from strongly acidic media (1 < pH < 2). Among common divalent metal ions, in addition, the resin exhibits the highest selectivity toward lead ion. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1327–1334, 1997  相似文献   
45.
The role of abduction in chance discovery   总被引:1,自引:0,他引:1  
Recently, researches on discovery science and knowledge discovery have been carried out in various fields. Basically they are types of learning that learn tendencies from the sets of data of the same or similar categories. In this sense, discovery is to discover the tendencies. As a result, they cannot predict the events that are different from the trend. On the other hand, abduction is thought of as an explanatory reasoning. Indeed, abduction is a reasoning to generate hypotheses to explain an observation. However, the original meaning of abduction was to discover new things that cannot be known in a simple way. In this paper, abduction is defined using the original definition that discovers something that cannot be easily predicted. Then, this paper shows a role of abduction that can suggest or foresee the events that are different from the trend. In fact, Abductive Analogical Reasoning that can generate new hypotheses is adopted to solve the problem. Akinori Abe, Ph.D.: He obtained his Doctor of Engineering (Ph.D) from the University of Tokyo in 1991, with a thesis entitledA Fast Hypothetical Reasoning System using Analogical Case. His main research interests are abduction (hypothetical reasoning), analogical reasoning, chance dicovery and language sense processing. He is a member of the Planning Committee of the New Generation Computing. He worked in NTT MSC (Malaysia) from 2000 to 2002. Currently, he works in ATR.  相似文献   
46.
In this paper, a novel parameter space approach that uses volume rendering is proposed to visualize controller parameter sets that consist of three controller parameters. An off‐line design method for robust control using plant response data is also studied. A solution set with equal ?2 gain can be visualized as isosurfaces in three‐dimensional space, and the designer can visually select an appropriate parameter. This numerical method is applicable to many practical specifications, in contrast to analytical methods based on solving equations. An estimation method based on the extension theorem and a method using bandpass filters are both considered as possible methods for estimating the ?2 gain of the sensitivity functions when using grid points on the order of tens of thousands to create the volume data.The former method is superior to the latter with respect to accuracy but impractical with respect to computational load. The latter method is hence practical, because the computing time is reduced to less than 0.05 s for about 300,000 grid points by parallel computation with a graphical processing unit.  相似文献   
47.

Introduction

Multiply-accumulate operation is the most fundamental operation in digital signal processing for image processing, robotics and automatic control. In this paper, a novel architecture of dynamically reconfigurable fused multiply-adder (FMA) is proposed.

Methods

Dynamic reconfiguration is a method that can change the circuit configuration without stop of operation. The proposed circuit provides the following four calculation modes by dynamic reconfiguration: (1) complex number FMA mode, (2) real number FMA mode, (3) complex number parallel calculation mode, and (4) real number parallel calculation mode.  The data format is single precision floating point format based on IEEE754. The proposed circuit was designed using Verilog-HDL. It was simulated by logic circuit simulator, and implemented on FPGA.

Result

As a result of circuit synthesis, we confirmed the reduction of resource in the proposed circuit. Furthermore, we confirmed proper result for each calculation mode by logic simulation and experiment on FPGA.

Conclusion

The proposed circuit provides the four calculation modes by dynamic reconfiguration. We confirmed the reduction of resource and proper result for each calculation mode.  相似文献   
48.
This article proposes a novel genetic algorithm (GA) which switches the expression of the solution from a redundant binary number to a usual binary number. Furthermore, a GA which switches the expression from the Gray code to the usual binary number is proposed and compared. Comparisons of the performances among five GAs (binary number, redundant binary number, Gray code, switching from redundant binary number to binary number, switching from Gray code to binary number) are illustrated. The performances are evaluated by solving some equations. It is confirmed that the proposed GA effectively decreases the error rate.  相似文献   
49.
50.
    
An electronic nose prototype based on the novel temperature-modulation technique is developed, where the heater voltage changes its amplitude and frequency periodically. The system comprises a sensor analog front end and a digital processing part including a heater voltage generator and a sensor data transmitter, where the digital part was implemented by a field programmable gate array. The fabricated prototype successfully generated the modulated heater waveform and synchronously acquired sensor responses at a sampling rate of 10 kHz. Whereby, sensor responses to the test gases of volatile organic compounds were collected. Gas classification was achieved with an accuracy of 99.6% based on the data obtained by the prototype, demonstrating the promising properties of the prototype as a compact and highly precise electronic nose.  相似文献   
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