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101.
102.
We have implemented an automated, nonmechanical approach to the measurement of polarization dependent loss (and, equivalently, gain). We use a deterministic fixed-states method to derive Mueller matrix elements from intensity measurements at specific polarization states. Voltage-modulated liquid-crystal variable retarders set the polarization states. Synchronous detection is employed to increase the signal-to-noise ratio (SNR) of the system and thereby allow measurement resolution to better than 0.001 dB. We present polarization-dependent loss measurements from 0.0016 to 0.56 dB at 1550 nm to verify performance 相似文献
103.
In this paper, we provide a complete framework for the design of genetically evolved cognitive tracking controller based on interval type-2 (IT2) fuzzy cognitive map (FCM). We construct the cognitive controller based on a nonlinear controller by transforming its representation into a FCM. This representation gives the opportunity to prove the stability of the cognitive controller in the framework of nonlinear control theory. Moreover, with the deployment of IT2-fuzzy sets which are known to be capable to handle high level of uncertainty, the proposed cognitive controller has the ability to deal with uncertainty that are encountered in real-time world applications. To accomplish the design of the cognitive controller, we present a systematic approach based on genetic algorithm to optimize its parameters and learn fuzzy rules by extracting them from model space (e.g., a set of rules). Within the paper, all steps in constructing and designing the IT2-FCM-based cognitive controller are presented. We first show the performance improvements of the proposed IT2-FCM-based tracking controller with extensive and comparative simulation results and then with experimental results that were collected on real-world mobile robot. The results clearly show the superiority of proposed cognitive control systems when compared to its conventional and fuzzy controller counterparts. We believe that the proposed genetically evolved design approach of the IT2-FCM-based cognitive controller will provide a bridge between the well-developed cognitive sciences and control theory. 相似文献
104.
R. Kompfner C. J. R. Sheppard D. Walsh A. Choudhury J. N. Gannaway P. G. Hale 《Scanning》1994,16(3):327-332
The following consists of extracts concerning near-field microscopy from a Progress Report prepared in April 1975 as Oxford University Engineering Laboratory Report No. 1883/77, describing work initiated by the late Professor R. Kompfner. Preliminary experimental work on near-field microscopy is outlined, and a theory for contrast formation is presented. 相似文献
105.
Capsella bursa-pastoris (L.) Medic. (shepherd's purse) has been tested as a possible biomonitor of heavy metals in the city of Bradford, UK and compared with Poa annua L. (annual meadow-grass), a species with a similar ecology that had previously been studied for biomonitoring potential. Forty-two sites (urban roadside, urban, urban park, suburban and rural) in and around Bradford were investigated. Concentrations of Pb, Cd, Zn and Cu have been determined in soils and in washed and unwashed plant leaves. Differences between the washed and unwashed samples, reflecting airborne and soil entry routes, respectively, varied according to the metal pollutant. There were significant relationships between the heavy metal concentration in samples of surface soil (depth 0-10 cm) and washed leaves, the concentrations being greater with progressively increased urbanisation of the sites. Capsella bursa-pastoris has been found to be a useful biomonitor of the four heavy metals studied, and it may be a particularly useful species since it could monitor short-term changes in pollution in urban areas. 相似文献
106.
107.
Sevim Köse Serkan Koral Yeşim Özoğul Bekir Tufan 《International Journal of Food Science & Technology》2010,45(8):1594-1602
This study demonstrates proximate composition and fatty acid profile of Pacific mullet caught in Turkey. The highest moisture and protein contents were observed with muscle tissues as 83.74 and 10.52%, while the highest fat and ash contents were attributed to female gonads as 11.80 and 0.94%, respectively, with a significant variation amongst months (P < 0.05). Significant variation (P < 0.05) usually occurred amongst months within the same sex for total saturated fatty acids ( ∑ SFA), monosaturated fatty acids ( ∑ MUFA), polyunsaturated fatty acids ( ∑ PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in muscle, although overall mean values between sexes were not found significant. Except for EPA, no variation observed for gonads while significant changes occurred (P < 0.05) with liver samples amongst months. Overall total values of ∑ SFA, ∑ MUFA, ∑ PUFA, DHA and EPA in muscle samples were 29.59, 29.26, 18.06 and 4.48%, respectively, while in gonads ranged as 30.26–33.23%, 35.17–37.47%, 11.87–14.88%, 4.38–5.34% and 3.02–5.02%. These FAs were 21.57–33.11%, 32.89–50.96%, 14.78–20.08%, 0.89–9.94% and 5.85–9.54% for liver, respectively. The results of this study showed that muscle and gonads of Pacific mullet were rich in n‐3 PUFA, especially, EPA, DHA, increasing the value of this species for human consumption. 相似文献
108.
Jonathan A. Hale 《The Journal of Architecture》2013,18(1):91-97
While it can be demonstrated historically that sophisticated craft processes predate systematic philosophy, we have yet to appreciate the significance of this fact for an approach to tectonics in architecture. If patterns of thought can, ultimately, be seen to arise out of patterns of action, it might be useful to consider the making process as a source of understanding about the physical world. This paper initially proposes an interdependence between this kind of knowledge and our sense of self- the idea that self-consciousness arises, ultimately, from our engagement with the external environment. By considering certain philosophers' work on the phenomenology of perception, as well as the influence of these ideas on the discussion of materiality in the fine arts, this paper suggests the possibility of a 'narrative tectonics', in describing the potential of our engagement with architecture. 相似文献
109.
[Correction Notice: An erratum for this article was reported in Vol 23(4) of Psychology and Aging (see record 2008-19072-007). The original article contained an incorrect DOI. The correct DOI is as follows: 10.1037/a0012577.] It has been hypothesized that older adults are especially susceptible to proactive interference (PI) and that this may contribute to age differences in working memory performance. In young adults, individual differences in PI affect both working memory and reasoning ability, but the relations between PI, working memory, and reasoning in older adults have not been examined. In the current study, young, old, and very old adults performed a modified operation span task that induced several cycles of PI buildup and release as well as two tests of abstract reasoning ability. Age differences in working memory scores increased as PI built up, consistent with the hypothesis that older adults are more susceptible to PI, but both young and older adults showed complete release from PI. Young adults' reasoning ability was best predicted by working memory performance under high PI conditions, replicating M. Bunting (2006). In contrast, older adults' reasoning ability was best predicted by their working memory performance under low PI conditions, thereby raising questions regarding the general role of susceptibility to PI in differences in higher cognitive function among older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Luchak GL Miller RK Belk KE Hale DS Michaelsen SA Johnson DD West RL Leak FW Cross HR Savell JW 《Meat science》1998,50(1):55-72
Top loin (TLS), top sirloin (TSS), and eye of round (EYS) steaks, and loin end (LRR) and blade end (BRR) rib, and eye of round (EYR) roasts were used to determine the effect of USDA quality grade, Choice or Select, external fat trim level, and internal temperature endpoint on sensory, chemical and cooking characteristics. Cuts cooked with external fat required slightly greater cooking times and had higher fat content in the lean than cuts cooked without external fat (p < 0.05). Regardless of quality grade or external fat trim, increasing internal temperature endpoint resulted in tougher, drier cuts with longer cooking times and greater cooking loss (p < 0.05). Choice TLS, TSS and LRR were higher (p < 0.05) in palatability than Select, but quality grade did not affect palatability of BRR, EYS or EYR. 相似文献