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11.
对现行钢结构设计规范,包括中国规范(GB50017—2003)、美国规范(LRFD)、欧洲规范(EC3)和香港标准(HKC),进行了较详尽的比较,讨论了梁柱设计的各种原理和流程,总结了各规范设计方法的相似性与不同点。LRFD只利用一个验算方程来设计框架柱,而其他三种规范均需进行截面承载力、平面内稳定和平面外稳定承载力验算。比较发现,四种规范或标准各有优缺点,没有哪一种规范在各个方面均比其它规范更为优越。 相似文献
12.
介绍了东大盛世华庭部分防火设计;通过现行规范与性能规范对比,说明我国建筑防火设计向“性能化”发展的必然趋势和必要性。 相似文献
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14.
You-Fu Yang 《Journal of Constructional Steel Research》2006,62(12):1310-1324
This paper describes a series of tests on steel tubular columns of circular and square section filled with normal concrete and recycled aggregate concrete. Thirty specimens, including 24 recycled aggregate concrete filled steel tubular (RACFST) columns and 6 normal concrete filled steel tubular (CFST) columns, were tested to investigate the influence of variations in the tube shape, circular or square, concrete type, normal concrete and recycled aggregate concrete, and load eccentricity ratio, from 0 to 0.53 on the performance of such composite columns. The test results show that both types of filled columns failed due to overall buckling. Comparisons are made with predicted ultimate strengths of RACFST columns using the existing codes, such as ACI 318-1999, AIJ-1997, AISC-LRFD-1999, BS5400-1979, DBJ13-51-2003 and EC4-1994. A theoretical model for normal CFST columns is adopted in this paper for RACFST columns. The predicted load versus deformation relationships are in good agreement with test results. 相似文献
15.
采用中国与欧洲钢结构设计规范二阶效应理论对单跨3层和双跨5层钢框架二阶弯矩进行设计计算,并与有限元软件Midas/Gen的计算结果进行了比较。中国和欧洲钢结构设计规范均考虑了初始缺陷对二阶弯矩的影响,在理论计算中采用放大侧端弯矩的方法计算二阶效应,中国钢结构设计规范计算结果比有限元计算结果大2%~5%,欧洲钢结构设计规范计算结果比有限元计算结果大7%~15%,中国钢结构设计规范更契合工程实际的需要。 相似文献
16.
以伊朗南阿油田项目中心处理站的消防系统设计为基础,说明了伊朗油田消防系统设计参数的选取.对比分析了国内外消防规范中对有关参数设计、计算时所采用的不同方法,介绍了伊朗南阿油田中心处理站消防设计的特点,以供相关设计人员参考。 相似文献
17.
Tunnels typically comprise large scale infrastructure projects, where a demand for an increased service life is present. The most recent large scale projects in the UK come with a requirement for a service life of 120 years. At the same time, the implementation of Eurocodes is becoming standard practice, the current provisions of which cover a service life of 50 years. On the other hand, temporary structures often do not need to be designed for a service life longer than a few years only. The present paper discusses a reliability life-cycle based methodology to adjust safety factors used in the design of tunnel linings in order to reach a specified service life, i.e. a variation of the safety factors used leading to an analogous reliability level at the start of the structures lifetime, which in turn provides a modification of the expected service life duration. As discussed herein, this procedure does not conflict the Eurocode provisions (one of the most referred standards in tunnel design) but it comes in line with the safety concept indicated in Eurocode 0 “Basis of Design”. 相似文献
18.
Marco Baldi Franco Chiaraluce Nicola Maturo Giacomo Ricciutelli Alessandro Ardito Francesco Barbaglio Stefano Finocchiaro Lorenzo Simone Ricard Abell Javier De Vicente Mattia Mercolino 《International Journal of Satellite Communications and Networking》2019,37(6):571-587
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts. 相似文献
19.
The Alamouti space‐time block code (STBC) achieves full diversity gain at a rate of 1/2. However, the Alamouti scheme does not provide multiplexing gain. The Silver code offers both diversity and multiplexing gain. It has a minimum normalization determinant of . The Golden code is another STBC that offers both diversity and multiplexing gain. The Golden code is ranked higher than the Silver code because of its lower minimum normalization determinant of , however, the golden code suffers from a high detection complexity in the modulation order of M4. The 3/4‐Sezginer code is another STBC, which compromises between the Alamouti scheme and the Golden code in terms of diversity gain and multiplexing gain. The 3/4‐Sezginer code achieves full diversity and half of multiplexing gain. The uncoded space‐time labeling diversity (USTLD) is a recent scheme that improves the error performance when applied to the STBC in multiple‐input multiple‐output (MIMO) systems and will be applied to the 3/4‐Sezginer STBC to improve the error performance in this paper. The theoretical error probability for both the 3/4‐Sezginer STBC and the improved system is formulated using the union bound in this paper. The theoretical error probabilities of both 16‐QAM and 64‐QAM are validated through Monte Carlo simulation. The simulation and theoretical results show that the proposed system with 4 NR can achieve an SNR gain of 1 dB for 16‐QAM and 1.2 dB 64‐QAM at a bit error rate (BER) of 10?6. 相似文献
20.