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91.
Cepel R Ho KC Rinker BA Palmer DD Lerch TP Neal SP 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2007,54(9):1841-1850
In ultrasonics, image formation and detection are generally based on signal amplitude. In this paper, we introduce correlation coefficient images as a signal-amplitude independent approach for image formation. The correlation coefficients are calculated between A-scans digitized at adjacent measurement positions. In these images, defects are revealed as regions of high or low correlation relative to the background correlations associated with noise. Correlation coefficient and C-scan images are shown to demonstrate flat-bottom-hole detection in a stainless steel annular ring and crack detection in an aluminum aircraft structure. 相似文献
92.
Donato G Bartlett MS Hager JC Ekman P Sejnowski TJ 《IEEE transactions on pattern analysis and machine intelligence》1999,21(10):974
The Facial Action Coding System (FACS) [23] is an objective method for quantifying facial movement in terms of component actions. This system is widely used in behavioral investigations of emotion, cognitive processes, and social interaction. The coding is presently performed by highly trained human experts. This paper explores and compares techniques for automatically recognizing facial actions in sequences of images. These techniques include analysis of facial motion through estimation of optical flow; holistic spatial analysis, such as principal component analysis, independent component analysis, local feature analysis, and linear discriminant analysis; and methods based on the outputs of local filters, such as Gabor wavelet representations and local principal components. Performance of these systems is compared to naive and expert human subjects. Best performances were obtained using the Gabor wavelet representation and the independent component representation, both of which achieved 96 percent accuracy for classifying 12 facial actions of the upper and lower face. The results provide converging evidence for the importance of using local filters, high spatial frequencies, and statistical independence for classifying facial actions. 相似文献
93.
Sang Gil Lee Terrence M. Vance Tae-Gyu Nam Dae-Ok Kim Sung I. Koo Ock K. Chun 《Sensing and Instrumentation for Food Quality and Safety》2016,10(3):562-568
The present study evaluated the accuracy of pH differential (PD) method and HPLC method expressed as cyanidin-3-glucoside equivalent (CGE) for measuring total anthocyanin (TA) contents of five berries. Major anthocyanins of blueberry, blackberry, black currant, raspberry, and cranberry were analyzed with quantitative HPLC (q-HPLC) method using individual anthocyanin standards and used as a standard reference of comparison. PD method and HPLC method showed similar trend, although absolute amounts of TA differed in blueberry and cranberry. However, data showed that the TA of black currant and raspberry expressed as CGE considerably deviated from those obtained by q-HPLC. This discrepancy was due to underestimating TA of these two berries which contain disaccharides as major glycones, when expressed as CGE. On the other hand, when expressed as their major anthocyanin equivalents, TA of these two berries showed better approximate values with those by q-HPLC method. In addition, this finding was confirmed by Bland–Altman analysis. Our findings demonstrated that the type of glycone in berries is a critical factor to cause discrepancy between TA as CGE and actual TA and should be considered for measuring TA contents. 相似文献
94.
Seidman Edward; Golding Stephen L.; Hogan Terrence P.; LeBow Michael D. 《Canadian Metallurgical Quarterly》1974,42(1):10
Notes that despite a rapidly expanding literature on the A-B therapist-type variable, an adequate conceptual and empirical understanding has not been forthcoming. The present study endeavored to increase the limited understanding of the A-B dimension as well as to compare 3 different versions of the A-B scale. A battery of interest, personality, and aptitude tests (e.g., the SVIB) was completed by 231 undergraduate males. This battery was subjected to a 2-step principal components analysis in order to minimize the effects of method-specific sources of variance. Each of the 3 A-B scales was then regressed against component scores, followed by multiple discriminant-function analyses. Results indicate that 2 of the 3 A-B scales seem to be tapping a dimension tentatively labeled as a "social interpersonal orientation vs an impersonal cognitively complex orientation toward concepts and things." Explanations for some inconsistencies in the literature, for the nature of the Therapist * Patient Type interaction effect, and for possible strategies for future research are discussed. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Dagenbach Dale; Carr Thomas H.; Barnhardt Terrence M. 《Canadian Metallurgical Quarterly》1990,16(2):328
Semantic priming effects from newly learned vocabulary words are examined in a lexical decision task. At low levels of learning, those primes whose meanings are recognizable but not recallable can inhibit responses to well-known, semantically related target words, whereas those whose meaning are recallable produce either no effect or facilitation, depending on instructions concerning how to use the prime information. These results are consistent with the notion that semantic priming effects are determined at least in part by the nature of the retrieval operations performed on the prime and target, over and above influences due to spreading activation and confirmed or violated expectations. Specifically, they indicate a need to include mechanisms other than violated expectations that can produce inhibition of retrieval. Candidate mechanisms are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
The entire ★★ data base for the dependence of the nonstoichiometry, , on temperature and chemical potential of oxygen (oxygen potential) was retrieved from the literature and represented. This data base was interpreted by least-squares analysis using equations derived from the classical thermodynamic theory for the solid solution of a solute in a solvent. For hyperstoichiometric oxide at oxygen potentials more positive than , the data were best represented by a solution. For O/U ratios above 2 and oxygen potentials below this boundary, a solution represented the data. The data were represented by a solution. The resulting equations represent the experimental behavior and can be used in thermodynamic calculations to predict phase boundary compositions consistent with the literature. Collectively, the present analysis permits, for the first time, a mathematical representation of the behavior of the total data base. 相似文献
97.
Neurons in sensory systems convey information about physical stimuli in their spike trains. In vitro, single neurons respond precisely and reliably to the repeated injection of the same fluctuating current, producing regions of elevated firing rate, termed events. Analysis of these spike trains reveals that multiple distinct spike patterns can be identified as trial-to-trial correlations between spike times (Fellous, Tiesinga, Thomas, & Sejnowski, 2004 ). Finding events in data with realistic spiking statistics is challenging because events belonging to different spike patterns may overlap. We propose a method for finding spiking events that uses contextual information to disambiguate which pattern a trial belongs to. The procedure can be applied to spike trains of the same neuron across multiple trials to detect and separate responses obtained during different brain states. The procedure can also be applied to spike trains from multiple simultaneously recorded neurons in order to identify volleys of near-synchronous activity or to distinguish between excitatory and inhibitory neurons. The procedure was tested using artificial data as well as recordings in vitro in response to fluctuating current waveforms. 相似文献
98.
Communication and Information Systems (CIS) now form the primary information store, exchange and data analysis for all modern military and are crucial to command and control. The ubiquitousness of CIS within the military not only means that there is a complete reliance on CIS, but also presents new avenues of attack by malicious insiders. Military sources say that the insider threat is their number one security concern. This paper presents a case study of the technical counter measures and processes used to deter, detect and mitigate malicious insider threats that the author has researched, using non-classified anonymous interview and the analysis of anonymised qualitative field data, within a specific military organisation. It is not the intention of the author that this paper be viewed as an analysis of the “current state of play” of threats and countermeasures that generically exist across all military and defence organisations – rather it presents the technological and organisational processes utilised and challenges encountered at one organisation. A short discussion of the Computer Security Incident Response Team (CSIRT) structure adopted to successfully manage insider and other CIS security threats is presented, followed by a more detailed overview of existing and emerging technical efforts to deter, detect and mitigate such malicious insider threats within the military environment under study. Emphasis will be on the emerging technologies such as anomaly detection using real-time e-discovery, enterprise forensics and profiling users “cyber” behaviour and how these integrate into CSIRT technologies and processes. The technical advantages and challenges that such technologies present within a military alliance will be discussed. The success of such technologies in combating current malicious insider threat environment will be briefly compared with those put forward as challenges in the “Research on mitigating the insider threat to information systems #2” workgroup which took place in 2000 (Anderson et al., 2000.). In closing the author introduce the concept of Stateful Object Use Consequence Analysis as a way of managing the insider threat. 相似文献
99.
Simultaneous planar laser-induced incandescence, hydroxyl radical planar laser-induced fluorescence, and droplet Mie scattering are used to study the instantaneous flame structure and soot formation process in an atmospheric pressure, swirl-stabilized, liquid-fueled, model gas-turbine combustor. Optimal excitation and detection schemes to maximize single-shot signals and avoid interferences from soot-laden flame emission are discussed. The data indicate that rich pockets of premixed fuel and air along the interface between the spray flame and the recirculation zone serve as primary sites for soot inception. Intermittent large-scale structures and local equivalence ratio are also found to play an important role in soot formation. 相似文献
100.
A time-gated ballistic imaging instrument is used to obtain high-spatial-resolution, single-shot images of the liquid core in a water spray issuing into a gaseous crossflow. We describe further development of the diagnostic technique to improve spatial resolution and present images and statistics for various jets under crossflow experimental conditions (different Weber numbers). Series of these images reveal a near-nozzle flow field undergoing breakup and subsequent droplet formation by stripping. One can also detect signatures of spatially periodic behavior in the liquid core and formation of small voids during breakup. 相似文献