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101.
Prof. Dr. Erwin Grochla Direktor Betriebswirtschaftliches Institut für Organisation und Automation an der Universit?t zu
K?ln K?ln Deutschland 《WIRTSCHAFTSINFORMATIK》2009,51(1):104-109
Zusammenfassung Nachdruck eines Aufsatzes aus elektronische datenverarbeitung 11(11)1969:544–548.
This article is also available in English via and : Grochla E (2008) Corporate Information Systems Engineering and Business and Information Systems Engineering as a Necessary
Application-Oriented Extension of General Computer Science – Proposals for Enhancing Academic Education in the Field of Automated
Data Processing in the Federal Republic of Germany. Bus Inf Syst Eng. doi .
相似文献
相似文献
102.
Konrad?SiekEmail author Pawe??T.?Wojciechowski 《International journal of parallel programming》2016,44(3):598-619
This paper presents Atomic RMI, a distributed transactional memory framework that supports the control flow model of execution. Atomic RMI extends Java RMI with distributed transactions that can run on many Java virtual machines located on different network nodes. Our system employs SVA, a fully-pessimistic concurrency control algorithm that provides exclusive access to shared objects and supports rollback and fault tolerance. SVA is capable of achieving a relatively high level of parallelism by interweaving transactions that access the same objects and by making transactions that do not share objects independent of one another. It also allows any operations within transactions, including irrevocable ones, like system calls, and provides an unobtrusive API. Our evaluation shows that in most cases Atomic RMI performs better than fine grained mutual-exclusion and read/write locking mechanisms. Atomic RMI also performs better than an optimistic transactional memory in environments with high contention and a high ratio of write operations, while being competitive otherwise. 相似文献
103.
In this paper a novel Tensor-Based Image Segmentation Algorithm (TBISA) is presented, which is dedicated for segmentation of colour images. A purpose of TBISA is to distinguish specific objects based on their characteristics, i.e. shape, colour, texture, or a mixture of these features. All of those information are available in colour channel data. Nonetheless, performing image analysis on the pixel level using RGB values, does not allow to access information on texture which is hidden in relation between neighbouring pixels. Therefore, to take full advantage of all available information, we propose to incorporate the Structural Tensors as a feature extraction method. It forms enriched feature set which, apart from colour and intensity, conveys also information of texture. This set is next processed by different classification algorithms for image segmentation. Quality of TBISA is evaluated in a series of experiments carried on benchmark images. Obtained results prove that the proposed method allows accurate and fast image segmentation. 相似文献
104.
105.
106.
OBJECTIVE: This study investigated the effects of drivers' age and low light on speed, lane keeping, and visual recognition of typical roadway stimuli. BACKGROUND: Poor visibility, which is exacerbated by age-related changes in vision, is a leading contributor to fatal nighttime crashes. There is little evidence, however, concerning the extent to which drivers recognize and compensate for their visual limitations at night. METHOD: Young, middle-aged, and elder participants drove on a closed road course in day and night conditions at a "comfortable" speed without speedometer information. During night tests, headlight intensity was varied over a range of 1.5 log units using neutral density filters. RESULTS: Average speed and recognition of road signs decreased significantly as functions of increased age and reduced illumination. Recognition of pedestrians at night was significantly enhanced by retroreflective markings of limb joints as compared with markings of the torso, and this benefit was greater for middle-aged and elder drivers. Lane keeping showed nonlinear effects of lighting, which interacted with task conditions and drivers' lateral bias, indicating that older drivers drove more cautiously in low light. CONCLUSION: Consistent with the hypothesis that drivers misjudge their visual abilities at night, participants of all age groups failed to compensate fully for diminished visual recognition abilities in low light, although older drivers behaved more cautiously than the younger groups. APPLICATION: These findings highlight the importance of educating all road users about the limitations of night vision and provide new evidence that retroreflective markings of the limbs can be of great benefit to pedestrians' safety at night. 相似文献
107.
QuadCover - Surface Parameterization using Branched Coverings 总被引:4,自引:0,他引:4
We introduce an algorithm for the automatic computation of global parameterizations on arbitrary simplicial 2-manifolds, whose parameter lines are guided by a given frame field, for example, by principal curvature frames. The parameter lines are globally continuous and allow a remeshing of the surface into quadrilaterals. The algorithm converts a given frame field into a single vector field on a branched covering of the 2-manifold and generates an integrable vector field by a Hodge decomposition on the covering space. Except for an optional smoothing and alignment of the initial frame field, the algorithm is fully automatic and generates high quality quadrilateral meshes. 相似文献
108.
A cross-sectional study of task demands and musculoskeletal discomfort among a sample of 100 wait staff in ten casual dining restaurants was conducted. In addition to answering a questionnaire about musculoskeletal discomfort and symptoms experienced in the past 12 months and attributed to work, subjects were asked about various aspects of their jobs, such as shift length, number of shifts per week and safety training. The managers of the restaurants were also interviewed to gather basic information on factors such as work hours, alternative duty availability and safety practices. When asked to rank the three most important causes of injuries, the responses of both managers and wait staff were congruent with Bureau of Labor Statistics (USA) data for 1999 on the nature of injuries and attributed exposures, with slips and falls, musculoskeletal disorders and acute injuries (e.g. burns, cuts) highlighted. Of the 100 subjects, 42% reported experiencing musculoskeletal symptoms in the past year, with the lower back area (18%) and shoulder (11%) with the most frequent symptoms reported in the responses. Although many of the materials handling tasks were not excessive, the heavier tray lifts and carries are a cause for concern. There are also slip and fall issues that influence the risks of these tasks. Future research needs, including addressing the mismatch between more common materials handling assessment tools and the nature of food serving tasks, are discussed. 相似文献
109.
Peter Gottesmann und Reiner Hamm 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,178(5):366-370
Zusammenfassung Veränderungen in der subcellulären Verteilung der Mitochondrien-Enzyme Lipoamiddehydrogenase (LIPDH), Citratsynthase (CS) und -Hydroxyacyl-CoA-dehydrogenase (HADH) im Muskelgewebe lassen Aufschlüsse über Art und Ausmaß von Schädigungen der Muskelmitochondrien während der Lagerung und Behandlung von Fleisch erwarten und können möglicherweise als Grundlage für Methoden zur Unterscheidung zwischen Frischfleisch und aufgetautem Gefrierfleisch dienen. — Es werden Standardverfahren zur Bestimmung der Aktivität von LIPDH, CS und HADH in Gewebeextrakten und Muskelpreßsaft beschrieben. Der Einfluß von Enzymkonzentration, pH-Wert und Temperatur auf die Enzymaktivitäten im Muskelextrakt wurde untersucht. Ferner wurden die Streubreiten der mit den Standard-methoden gemessenen Enzymaktivitäten ermittelt.
Diese Arbeit ist Teil einer Dissertation von P. Gottesmann (Technische Universität München, 1982); sie wurde durch Mittel des Bundesministeriums für Jugend, Familie und Gesundheit unterstützt 相似文献
Lipoamide dehydrogenase, citrate synthase, and-hydroxyacyl-coenzyme A-dehydrogenase of skeletal muscleI. Studies on the determination of activities in tissue extracts
Summary It is to be expected that changes in the subcellular distribution of the mitochondrial enzymes lipoamide dehydrogenase (LIPDH), citrate synthase (CS) and -Hdroxyacyl-CoA-dehydrogenase (HADH) in the muscle tissue give information on the type and the extent of damage of mitochondria during storage and treatment of meats; such changes may be also used as basis of methods for the differentiation between fresh and frozen/thawed meat. — Standard methods for the determination of the activities of LIPDH, CS, and HADH in tissue extract and muscle press juice are described. The influence of enzyme concentration, pH and temperature on the enzyme activities in muscle extract was investigated. Furthermore the error in the enzyme analyses by the standard methods was determined.
Diese Arbeit ist Teil einer Dissertation von P. Gottesmann (Technische Universität München, 1982); sie wurde durch Mittel des Bundesministeriums für Jugend, Familie und Gesundheit unterstützt 相似文献
110.
Herbert Wieser Wolfgang Stempfl Werner Grosch und Hans-Dieter Belitz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(6):447-449
Zusammenfassung Achtzehn Fettsäuren, Fettsäuremethylester und Fettalkohole, emulgiert in Wasser mit Sucrosepalmitatstearat, wurden auf ihre Geschmacksqualität untersucht; bei bitterschmeckenden Verbindungen wurden die Schwellenwerte bestimmt. Die Intensität des Bittergeschmacks von Fettsäuren und Fettalkoholen hängt von der Länge des Alkylrestes sowie von der Anzahl, der Konfiguration und der Position der Doppelbindungen ab. Linol- und Linolensäuremethylester schmecken nicht bitter. -Linolenylalkohol und -Linolensäure haben die niedrigsten Schwellenwerte (0,2–0,5 bzw. 0,6–1,2 mmol/l) und liegen etwa im gleichen Bereich wie Coffein (0,8–1,2 mmol/l).
Studies of the bitter taste of fatty acid emulsions
Summary Eighteen fatty acids, methyl esters of fatty acids and fatty alcohols emulsified in water with sucrose palmitate stearate were tested for taste quality. In the case of bitter tasting compounds the taste thresholds were determined. The intensity of bitter taste of fatty acids and fatty alcohols is dependent on the length of the hydrocarbon chain and on the number, the configuration and the positions of double bonds. The methyl esters of linoleic and linolenic acid are not bitter. Gamma-linolenyl alcohol and alphalinolenic acid have the lowest threshold values (0.2–0.5 and 0.6–1.2 mmol/l), similar to that of caffeine (0.8–1.2 mmol/l).相似文献