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91.
92.
In this paper, a new approach to deal with textual attributes in databases is presented. The basic idea is to give a new representation for these attributes, so that it allows us to treat them together with and in the same way than the other database attributes in querying, data warehousing, data mining processes, etc. Additionally, the transformation process of the textual attribute implies the obtaining of a global representation, which includes a great part of the attribute meaning. Moreover, this representation can be improved by using an ontology during the querying process, which enables the semantic queries. The formal representation model is presented in the paper, as well as the mathematical bases for dealing with it. The whole implementation process is also described by using a medical database to show the experimental results. Finally, a set of semantic query examples are offered to explain the advantages of this new approach. 相似文献
93.
Sandro Gaycken 《Datenschutz und Datensicherheit - DuD》2011,35(5):346-350
Durch die juristische und die technische Komplexit?t von überwachung und Datenschutz muss das die informationelle Selbstbestimmung
herstellende sichere Wissen heute durch Vertrauen ersetzt werden. Allerdings wird dieses Vertrauen nicht objektiv und rational,
sondern subjektiv und reduziert-rational gebildet. Dies ist eine folgenreiche Einschr?nkung, da so die Voraussetzungen für
gesellschaftlich breites informationelles Vertrauen variiert werden und gegenw?rtig kaum herzustellen sind. 相似文献
94.
One of the key problems in machine learning theory and practice is setting the correct value of the regularization parameter; this is particularly crucial in Kernel Machines such as Support Vector Machines, Regularized Least Square or Neural Networks with Weight Decay terms. Well known methods such as Leave-One-Out (or GCV) and Evidence Maximization offer a way of predicting the regularization parameter. This work points out the failure of these methods for predicting the regularization parameter when coping with the, apparently trivial and here introduced, regularized mean problem; this is the simplest form of Tikhonov regularization, that, in turn, is the primal form of the learning algorithm Regularized Least Squares. This controlled environment gives the possibility to define oracular notions of regularization and to experiment new methodologies for predicting the regularization parameter that can be extended to the more general regression case. The analysis stems from James–Stein theory, shows the equivalence of shrinking and regularization and is carried using multiple kernels learning for regression and SVD analysis; a mean value estimator is built, first via a rational function and secondly via a balanced neural network architecture suitable for estimating statistical quantities and gaining symmetric expectations. The obtained results show that a non-linear analysis of the sample and a non-linear estimation of the mean obtained by neural networks can be profitably used to improve the accuracy of mean value estimations, especially when a small number of realizations is provided. 相似文献
95.
Hobfoll Stevan E.; Palmieri Patrick A.; Johnson Robert J.; Canetti-Nisim Daphna; Hall Brian J.; Galea Sandro 《Canadian Metallurgical Quarterly》2009,77(1):138
This is the 1st longitudinal examination of trajectories of resilience and resistance (rather than ill-being) among a national sample under ongoing threat of mass casualty. The authors interviewed a nationally representative sample of Jews and Arabs in Israel (N = 709) at 2 times during a period of terrorist and rocket attacks (2004?2005). The resistance trajectory, exhibiting few or no symptoms of traumatic stress and depression at both time points, was substantially less common (22.1%) than has previously been documented in studies following single mass casualty events. The resilience trajectory, exhibiting initial symptoms and becoming relatively nonsymptomatic, was evidenced by 13.5% of interviewees. The chronic distress trajectory was documented among a majority of participants (54.0%), and a small proportion of persons were initially relatively symptom-free but became distressed (termed delayed distress trajectory; 10.3%). Less psychosocial resource loss and majority status (Jewish) were the most consistent predictors of resistance and resilience trajectories, followed by greater socioeconomic status, greater support from friends, and less report of posttraumatic growth. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Valerio Causin Massimo L. Carraro Carla Marega Roberta Saini Sandro Campestrini Antonio Marigo 《应用聚合物科学杂志》2008,109(4):2354-2361
Nanocomposites based on poly(vinylidene fluoride) were prepared with montmorillonite by solution blending. The samples were characterized by small angle X‐ray scattering, wide angle X‐ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. Different crystallization conditions, that is, evaporation of the solvent and coprecipitation with two different antisolvents, H2O or supercritical CO2 (scCO2), were tested and their influence on the resulting structure and morphology of the samples were studied. Coprecipitation with scCO2 induced an ordinate crystalline framework and an intercalated morphology of clay, with a consequent large improvement in modulus. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
97.
Chiara P. Ryffel Celine M. Muehlethaler Sandro M. Huber Achim Elfering 《Ergonomics》2019,62(2):319-329
AbstractUpset prevention and recovery training (UPRT) is intended to improve the ability of pilots to recognize and avoid situations that can lead to airplane upsets and to improve their ability to recover control of an airplane that has exceeded the normal flight envelope. To this end, a set of different training contents – from theoretical knowledge of aerodynamics and human factors to practice-based flight training – is necessary. In order to support the debriefing with an objective feedback, and because visual scanning is a core competence, two studies on subjective evaluation of aviation pilots – one conducted in a flight simulator and the other one in-flight – focussed on the practical application of eye tracking as a debriefing tool in UPRT. From a practitioner’s perspective, eye tracking appeared to be a useful method in terms of visualising instrument scanning techniques, supporting the instructor with objective debriefing material and fostering self-awareness in human processes. The discussion recommends adjusted UPRT instructor training and further improvements to eye tracking hardware and software.Practitioner Summary: The article focuses on pilot evaluations of eye tracking as a debriefing tool in UPRT and the identification of critical elements in its use. Eye tracking is a promising debriefing tool for UPRT. The discussion points to desirable improvements of eye tracking hardware and software as well as adjustments to instructor training that are pertinent. 相似文献
98.
99.
Moh’d Sami Ashhab Thilo Breitsprecher Sandro Wartzack 《Journal of Intelligent Manufacturing》2014,25(1):77-84
A combined deep drawing–extrusion process is modeled with artificial neural networks (ANN’s). The process is used for manufacturing synchronizer rings and it combines sheet and bulk metal forming processes. Input–output data relevant to the process was collected. The inputs represent geometrical parameters of the synchronizer ring and the outputs are the total equivalent plastic strain (TEPS), contact ratio and forming force. This data is used to train the ANN which approximates the input-output relation well and therefore can be relied on in predicting the process input parameters that will result in desired outputs provided by the designer. The complex method constrained optimization is applied to the ANN model to find the inputs or geometrical parameters that will produce the desired or optimum values of TEPS, contact ratio and forming force. This information will be very hard to obtain by just looking at the available historical input–output data. Therefore, the presented technique is very useful for selection of process design parameters to obtain desired product properties. 相似文献
100.
Sandro Salmoiraghi 《纺织导报》2010,(6)
<正>意大利纺织机械制造商对本届ITMA ASIA+CITME 2010的参与态度非常积极,参展商总数达到了110家,展出总面积达3900m2,其中,67家企业将加入由意 相似文献