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991.
基于C8051 F340的多直流电机控制系统的设计 总被引:2,自引:0,他引:2
多电机的协调工作是机器人控制领域的关键技术之一.提出了以C8051F340为控制器、LMD18200为电机驱动器的解决方案.详细介绍了其硬件设计和软件实现方法.在机械手的运动控制应用中,该控制方法结构简单、可靠. 相似文献
992.
不同功能单体对分子印迹聚合物识别性能的模拟 总被引:1,自引:0,他引:1
以槲皮素为模板分子,以甲基丙烯酸(MAA)、三氟甲基丙烯酸(TFMAA)、丙烯酰胺(AM)、N-乙烯基吡咯烷酮(NVP)、2-乙烯基吡啶(2-VP)、4-乙烯基吡啶(4-VP)六种物质分别作为功能单体,运用量子化学方法模拟模板分子与不同功能单体的分子印迹聚合物预组装体系的构型、能量及复合反应的结合能△E,以讨论不同功能单体对分子印迹聚合物识别性能的影响,结果4-VP的印迹效应最好.通过模拟,有助于解释实验现象以及选择印迹效应更好的功能单体. 相似文献
993.
Chang‐Wook Han Yoon‐Heung Tak In Byeong Kang Byung‐Chul Ahn In Jae Chung 《Journal of the Society for Information Display》2009,17(2):101-106
Abstract— An improved AMOLED with an a‐Si TFT backplane based on a unique structure is reported. The new structure is refered to as a dual‐plate OLED display (DOD). While a top‐emission OLED array is directly fabricated on a TFT backplane, the DOD consists of an upper OLED substrate and a lower TFT substrate, which are independently fabricated. Because the OLED substrate, which is fabricated through the process flow of bottom emission, is attached to the TFT substrate, the light is emitted in the opposite direction to the TFT backplane. The DOD enables the design of large‐sized TFTs and a complicated pixel circuit. It can also not only achieve higher uniformity in luminance in large‐sized displays due to the low electrical resistance of the common electrode, but also wider viewing angles. 相似文献
994.
Natheer Abu-Obeid Fuad K. Malkawi Khaled Nassar Basel Al-eideh 《Nexus Network Journal》2009,11(2):163-182
The main goal of this study is to apply a scientific quantitative approach to the investigation of contextual fit. This is
approached mathematically within the framework of cognitive science and research on categorization and prototypes. Two experiments
investigated two leading mathematical-cognitive approaches for explaining people’s judgment of contextual fit of a new building
with an architectural/urban context: prototype approach and feature frequency approach. The basic concept is that people represent
the built environment via architectural prototypes and/or frequencies of encountered architectural features. In the first
experiment, a group of twelve participants performed rank order tasks on artificially created architectural patterns, for
the purpose of psychological scaling. Perceptual distances among all patterns were mathematically determined. In the second
experiment, three groups of architectural patterns were constructed to represent assumed architectural contexts. The prototype
of each context was mathematically determined according to prototype cognitive model, and based on the distances calculated
in the first experiment. Fifty-six students participated in the main experiment, in which they rank ordered a group of fifteen
architectural patterns in terms of contextual fit to each of the three architectural contexts. Participants’ rank order data
of the fifteen patterns were regressed on both the perceptual distances from prototypes, and numbers of features shared with
each architectural context. Results indicated that both prototype and feature frequency approaches significantly accounted
for important portions of participants’ judgments. However, participants tended to prefer one approach to the other according
to context composition. Results have implications for both research on utilizing cognitive-mathematical models in architectural
research and on urban design guidelines and control. 相似文献
995.
Rachel Fletcher 《Nexus Network Journal》2009,11(1):105-128
The zodiac is widely known as a band of twelve celestial constellations. It also contains a mathematical model for cosmographic
depiction, based on observations of the sun, moon, and visible planets as they traverse the celestial ecliptic. Here wee consider
the zodiac as a timepiece or calendar; how this system of planets and constellations emerges from elementary geometric patterns;
and how these patterns inform the symbols of the zodiac and frame our world view. 相似文献
996.
Giulio Magli 《Nexus Network Journal》2009,11(1):35-50
The architectural complexes composed by the two main pyramids of Giza together with their temples are investigated from an
interdisciplinary point of view, taking into account their astronomical alignments as well as their relationships with the
visible landscape. Combining already known facts together with new clues, the work strongly supports the idea that the two
complexes were conceived as parts of a common project. 相似文献
997.
Continuity versus Discretization 总被引:1,自引:1,他引:0
The threefold interest in architecture, biology and mathematics motivated us to examine and justify new architectural forms.
We discuss some notions of rhythm: Euclidean, morphogenetic and morphologic. Contemporary relationships between structure
and form are based on the generation of shape by technological processes, thus the resulting objects are restricted to their
material expression. Here a phenomenological organisation of form and its continuity with the landscape arise out of the mathematical
and architectural creativity. The use of the computer is applied from outside to inside instead from inside to outside; this
means that we are dealing with the organisational processes via continuous methods instead of evolutionary processes given
by computer simulations, known as genetic algorithms, where the resulting configurations are reduced to a matter of routine. The role of design as an aesthetic component innovates
the theoretical framework of structural engineering to establish the architectural environments. 相似文献
998.
Sylvie Duvernoy 《Nexus Network Journal》2009,11(1):135-137
Sylvie Duvernoy reports on the seventh international, interdisciplinary Nexus conference for architecture and mathematics.
Point Loma Nazarene University, San Diego, USA 23-25 June 2008 相似文献
999.
Izumi Kuroishi 《Nexus Network Journal》2009,11(2):201-216
This paper presents an examination of the process of the development of module in the works and theories of Japanese architect
Ikebe Kiyoshi (1920-79). Ikebe based his idea of module on the belief that “Beauty is Mathematics.” He applied his ideas of
module in various ways from the 1940s to the 1970s. Analyzing his ideas and works against their historical background, the
social and creative meanings of the idea of module and of mathematics in architecture will be re-examined. This allows us
to see how Ikebe developed his ideas of module from a characteristic mathematical approach, and how he developed his idea
of mathematical logic into his creative theories based on the flexible nature of people’s lifestyles and social conditions.
Going beyond the cultural and social differences and the limitations of Le Corbusier’s Modulor, the idea of module as the
method for organizing human space in a harmonious manner was reframed in Ikebe’s works, and was developed in a more flexible
mathematical way. 相似文献
1000.
Ortwin Feustel 《Nexus Network Journal》2009,11(1):7-21
It is commonly believed that the longitudinal axes of churches extend exactly in an east-west direction. However, thorough
investigations have shown that this is not always correct; rather, both southern and northern deviations of up to about 25°
can occur. The angular deviation between the church axis and true east is called the Holy Alignment. This present study presents the possibility that the nave is oriented towards the direction of the sun-rising point on the
name day of the patron saint of the church. If several saints share the patronage, the Holy Alignment equals the algebraic sum of the angular distances for each saint. The orientation of a nave can be analyzed by means of common
mathematical relations used in geodesy, astronomy and gnomonics. In order to perform such an analysis, it is necessary to
know the history of the patronage of the church; the Gauss-Krüger coordinates of the ground plan; and characteristic astronomical
quantities at the time the church was built. A calculated example with the saints Andrew, James and Philip for the year 980
illustrates the analysis.
An appendix deals with the influence of atmospheric refraction on the apparent altitude of the sun near the horizon. 相似文献