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51.
Fedor L.S. Walsh E.J. Cavalieri D.J. 《Geoscience and Remote Sensing, IEEE Transactions on》1987,(3):393-402
In January 1984, a 36-GHz scanning pencil-beam radar was used at 175-m altitude over ice in the Greenland Sea to produce high-spatial-resolution (3 m by 5 m) topographic and backscattered power maps. Incidence angles from nadir to approximately 300 offnadir were included in the data set. When the radar maps were compared with the ice topography indicated by simultaneous photography and an analysis of the shadows of the ridges cast by the low sun angle (3.5°), it was found that the backscattered power data sharply delineated many of the features observed in the photography. The elevation data were less impressive but still consistent with the general variation of the topography. 相似文献
52.
Caldwell Steven D.; Herold David M.; Fedor Donald B. 《Canadian Metallurgical Quarterly》2004,89(5):868
Organizational behavior literature has not typically viewed person-environment (P-E) fit as an outcome of change. Whereas the study of antecedents to employees' fit with their work environment has largely been restricted to the selection and socialization of newcomers, this study examines individuals' perceptions of changes in P-E fit in relation to organizational changes occurring in 34 different organizational work units. Results suggest that the relationships between organizational change and perceived changes in fit are best understood as interactions between the characteristics of the change process, the extent of change, and individual differences. Both age and mastery orientation related to perceived changes in P-E fit through interactions with aspects of the change process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Vitalii E. Konoplev Irina V. Pisareva Eugenii V. Vorontsov Fedor M. Dolgushin Andreas Franken John D. Kennedy Igor T. Chizhevsky 《Inorganic chemistry communications》2003,6(12):1454-1458
Reactions of [OsCl2(PPh3)3] 1 with the [NEt4]+ salts of the [6-Ph-nido-6-CB9H11]− anion 2 and the [arachno-6-CB9H14]− anion 3 each proceed selectively in methanol solution with the elimination of one boron-containing fragment from the starting cluster polyhedron, yielding together a short series of three novel 10-vertex hydridoosmamonocarbaboranes of isocloso {OsCB8} cluster geometry. 相似文献
54.
Fedor Chernogorov Sergey Chernov Kimmo Brigatti Tapani Ristaniemi 《Wireless Networks》2016,22(6):2029-2048
This article presents an automatic malfunction detection framework based on data mining approach to analysis of network event sequences. The considered environment is long term evolution (LTE) of Universal Mobile Telecommunications System with sleeping cell caused by random access channel failure. Sleeping cell problem means unavailability of network service without triggered alarm. The proposed detection framework uses N-gram analysis for identification of abnormal behavior in sequences of network events. These events are collected with minimization of drive tests functionality standardized in LTE. Further processing applies dimensionality reduction, anomaly detection with K-Nearest Neighbors, cross-validation, postprocessing techniques and efficiency evaluation. Different anomaly detection approaches proposed in this paper are compared against each other with both classic data mining metrics, such as F-score and receiver operating characteristic curves, and a newly proposed heuristic approach. Achieved results demonstrate that the suggested method can be used in modern performance monitoring systems for reliable, timely and automatic detection of random access channel sleeping cells. 相似文献
55.
ABSTRACT: We report a novel synthesis of porous PbSe layers on Si substrates using anodic electrochemical treatment of PbSe/CaF2/Si(111) epitaxial structures in an electrolyte solution based on glacial acetic acid and nitric acid. Electron microscopy, x-ray diffractometry, and local chemical microanalysis investigations results for the porous layers are presented. Average size of the synthesized mesopores with ~1010 cm-2 surface density was determined to be 22 nm. The observed phenomenon of the active selenium redeposition on the mesopore walls during anodic treatment is discussed. 相似文献
56.
Martaus J Cambel V Gregusová D Kúdela R Fedor J 《Journal of nanoscience and nanotechnology》2010,10(7):4448-4453
A novel approach to local anodic oxidation technique, which leads to approximately equal 50 nm wide line patterns, is described. The technique is utilized to prepare quantum point contact on a low-mobility semiconductor heterostructure. Transport measurements show quantized conductance in zero magnetic field at 4.2 K thanks to very short one-dimensional constriction. The technique is also used for the definition of low-to-room temperature sub-micrometer Hall probes to show its applicability for the room temperature applications. The magnetic-field resolution and the sensitivity of the probes are evaluated in dependence of the probe dimensions, bias current, and temperature. The 200-nm probe shows magnetic-field resolution of 47 microT/(Hz)(1/2) at 140 Hz and at 4.2 K, when it is driven by 5 microA bias current. The novel approach is promising for the development of the future nano-devices operated both at low and room temperatures. To our knowledge, local anodic oxidation technique applied directly to shallow semiconductor heterostructure has been successfully used for the room temperature application for the first time. 相似文献
57.
Alexander Dontsov Marina Yakovleva Natalia Trofimova Natalia Sakina Alexander Gulin Arseny Aybush Fedor Gostev Alexander Vasin Tatiana Feldman Mikhail Ostrovsky 《International journal of molecular sciences》2022,23(3)
Aging of the retina is accompanied by a sharp increase in the content of lipofuscin granules and bisretinoid A2E in the cells of the retinal pigment epithelium (RPE) of the human eye. It is known that A2E can have a toxic effect on RPE cells. However, the specific mechanisms of the toxic effect of A2E are poorly understood. We investigated the effect of the products of photooxidative destruction of A2E on the modification of bovine serum albumin (BSA) and hemoglobin from bovine erythrocytes. A2E was irradiated with a blue light-emitting diode (LED) source (450 nm) or full visible light (400–700 nm) of a halogen lamp, and the resulting water-soluble products of photooxidative destruction were investigated for the content of carbonyl compounds by mass spectrometry and reaction with thiobarbituric acid. It has been shown that water-soluble products formed during A2E photooxidation and containing carbonyl compounds cause modification of serum albumin and hemoglobin, measured by an increase in fluorescence intensity at 440–455 nm. The antiglycation agent aminoguanidine inhibited the process of modification of proteins. It is assumed that water-soluble carbonyl products formed as a result of A2E photodestruction led to the formation of modified proteins, activation of the inflammation process, and, as a consequence, to the progression of various senile eye pathologies. 相似文献
58.
Hans L. Bodlaender Fedor V. Fomin Petr A. Golovach Yota Otachi Erik Jan van Leeuwen 《Algorithmica》2012,64(1):85-111
We study the problem of determining the spanning tree congestion of a?graph. We present some sharp contrasts in the parameterized complexity of this problem. First, we show that on apex-minor-free graphs, a general class of graphs containing planar graphs, graphs of bounded treewidth, and graphs of bounded genus, the problem to determine whether a given graph has spanning tree congestion at most k can be solved in linear time for every fixed k. We also show that for every fixed k and d the problem is solvable in linear time for graphs of degree at most d. In contrast, if we allow only one vertex of unbounded degree, the problem immediately becomes NP-complete for any fixed k??8. Moreover, the hardness result holds for graphs excluding the complete graph on 6 vertices as a minor. We also observe that for k??3 the problem becomes polynomially time solvable. 相似文献
59.
Hernychova L Toman R Ciampor F Hubalek M Vackova J Macela A Skultety L 《Analytical chemistry》2008,80(18):7097-7104
Rapid and reliable detection, identification, and typing of bacterial species are necessary in response to natural or terrorist-caused outbreaks of infectious diseases and play crucial roles in diagnosis and efficient treatment. We report here two proteomic approaches with a high potential in the detection and identification of Coxiella burnetii, the causative agent of Q fever. The first of them starts with the acetonitrile (ACN) and trichloroacetic acid extractions of inactivated C. burnetii cells followed by the detection of extracted molecules and ions derived from the inactivated cells by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. In the second approach, identification of the proteins extracted by ACN is accomplished after enzymatic digestion by electrospray tandem mass spectrometry coupled to a nanoscale ultraperformance liquid chromatography (LC-MS/MS). In order to observe morphological differences on the surface structures upon extraction, the inactivated and treated cells of the bacterium were examined by electron microscopy. The LC-MS/MS approach has allowed identification of 20 proteins in the ACN extracts of C. burnetii strain RSA 493 that were observed in more than 3 out of 10 experiments. 相似文献
60.
Cristina Bazgan Morgan Chopin Marek Cygan Michael R. Fellows Fedor V. Fomin Erik Jan van Leeuwen 《Journal of Computer and System Sciences》2014
The Firefighter problem is to place firefighters on the vertices of a graph to prevent a fire with known starting point from lighting up the entire graph. In each time step, a firefighter may be placed on an unburned vertex, permanently protecting it, and the fire spreads to all neighboring unprotected vertices of burning vertices. The goal is to let as few vertices burn as possible. In this paper, we consider a generalization of this problem, where at each time step b?1 firefighters can be deployed. Our results answer several open questions raised by Cai et al. [8]. We show that this problem is W[1]-hard when parameterized by the number of saved vertices, protected vertices, and burned vertices. We also investigate several combined parameterizations for which the problem is fixed-parameter tractable. Some of our algorithms improve on previously known algorithms. We also establish lower bounds to polynomial kernelization. 相似文献