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1.
Hamid R. Parsaei Mickey R. Wilhelm Sai S. Kolli 《Computers & Industrial Engineering》1993,25(1-4):357-360
Traditional economic evaluation methods concentrate on maximizing or minimizing a single objective such as net present value and pay back period. In the last decade, there has been an increased awareness of the need to consider multiple attributes in the evaluation of advanced manufacturing systems. Various methods have recently been developed for the evaluation of CIM systems. This paper discusses multiattribute methods for justification of CIM systems and outranking methods including ELECTRE, ORESTE, and PROMETHEE. 相似文献
2.
We define the very rich language of composed conditionals on a three‐valued logic and use this language as the communication tool between man and machine. Communication takes place for three reasons: knowledge acquisition, query, and response. Learning, thinking, and answering questions are of a pure information theoretical nature. The pivot of this knowledge processing concept is the amount of information (bit) we receive if a conditional becomes true. We follow an axiomatic approach to information theory rather than the classical probabilistic approach of Shannon; information comes first, and then comes probability. In the light of this philosophy, query and response experience new interpretations. Both, acquisition and response are realized by maximizing entropy and minimizing relative entropy, respectively. The iterative solution of these mathematical optimization problems gives new insights into the adaptation of prior knowledge to new information. Our expert system shell SPIRIT supports this kind of knowledge processing, which will be established by suitable examples. © 2003 Wiley Periodicals, Inc. 相似文献
3.
4.
S Ewig A Glasmacher B Ulrich K Wilhelm H Sch?fer KH Nachtsheim 《Canadian Metallurgical Quarterly》1998,114(2):444-451
STUDY OBJECTIVE: To determine predictors of mortality from pulmonary infiltrates in neutropenic patients with acute leukemia during chemotherapy, and the significance of those factors related to the underlying malignancy and its therapy as well as of those related to the severity of the illness associated with pulmonary infiltrates. DESIGN: A historical cohort study. SETTING: A university teaching hospital and tertiary referral center. PATIENTS AND METHODS: Overall, 53 patients with neutropenia during chemotherapy and with first episodes of pulmonary infiltrates during a 4-year period were studied. Prognostic analysis included 38 variables. Multivariate analyses were performed by logistic regression. RESULTS: The survival rate from pneumonia was 57% (30/53). The following eight parameters were significantly associated with death in univariate analysis: comorbidity present; development of "late" pulmonary infiltrates (> or = 14 days after hospital admission); heart rate > or = 100 beats/min; a ratio heart rate/systolic blood pressure (HR/SBP) > or = 1.2; urea nitrogen > 7 mmol/L; radiographic score > or = 3; neutropenia < 1.0x10(9)/L at the treatment end point; and failed complete remission. In a multivariate model including only parameters available at diagnosis of pulmonary infiltrates, the presence of a ratio HR/SBP > or = 1.2 and of a radiographic score > or = 3 remained independently associated with death. In a second model also including the evolutionary parameter neutropenia < or = 1.0x10(9)/L at the treatment end point, both parameters remained significant together with neutropenia <1.0x 10(9)/L at the treatment end point. The presence of a ratio HR/SBP > or = 1.2 was a strong marker of early death. CONCLUSION: Both therapy- and malignancy-associated neutropenia as well as the severity of illness associated with pulmonary infiltrates are independent prognostic factors. Patients with a ratio HR/SBP > or = 1.2 at diagnosis of pulmonary infiltrates suffer from potentially reversible acute illness, are at risk for early death and, therefore, may be appropriate candidates for treatment in an ICU. 相似文献
5.
Waldemar Kröner und Wilhelm Völksen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1943,85(2):169-172
Ohne ZusammenfassungDiese Z.83, 193 (1942). 相似文献
6.
Ravindranath G. Naick Wilhelm Pritzkow Jürgen Rasche 《Advanced Synthesis \u0026amp; Catalysis》1977,319(5):785-789
On the Autoxidation of Bicyclo[2,2,2]octene During the autoxidation of bicyclo[2,2,2]octene at 90°C about 50% of epoxide are obtained. The most important byproduct obviously is a polymeric peroxide. From the acidic products formed in low amounts, cis-1, 4-Cyclohexane dicarboxylic acid could be isolated as the corresponding dimethyl ester. 相似文献
7.
Microscale, quasi‐2D Au–polymer brush composite objects are fabricated by a versatile, controllable process based on microcontact printing followed by brush growth and etching of the substrate. These objects fold into 3D microstructures in response to a stimulus: crosslinked poly(glycidyl methacrylate) (PGMA) brushes fold on immersion in MeOH, and poly(methacryloxyethyl trimethylammonium chloride) (PMETAC) brushes fold on addition of salt. Microcages and microcontainers are fabricated. A multistep microcontact printing process is also used to create sheets of Au–PGMA bilayer lines linked by a PGMA film, which fold into cylindrical tubes. The bending of these objects can be predicted, and hence predefined during the synthesis process by controlling the parameters of the gold layer, and of the polymer brush. 相似文献
8.
A method based on the noise correlation technique and its applications is described. The package, which need not be reciprocal, may consist of an arbitrary interconnection of linear passive elements at thermal equilibrium. Only the terminal admittance properties of the package need be known. However, in certain special cases which lead to singular submatrices of the admittance matrix, the method is inapplicable. This situation can occur when elements such as isolators are part of the package. The necessary theoretical foundation and experimental techniques to enable workers not familiar with the field to assemble the software and laboratory setup for two-port noise de-embedding is provided. The automated noise measurement system used for data acquisition and the mathematical basis for it are described in some detail. The validity of the de-embedding approach is established with extensive experimental data obtained on three MESFETs and a pseudomorphic HEMT 相似文献
9.
Jochen Hohl‐Ebinger Wilhelm Warta 《Progress in Photovoltaics: Research and Applications》2011,19(5):573-579
Valuation of photovoltaic devices depends strongly on the measured power output of the device. This quantity is usually determined under artificial sunlight in production line measurement systems or industrial or research test labs. A practical calibration chain is realized essentially with measurements at solar simulators. The measurement conditions are defined in the IEC 60904 series of standards. An important part of the standard testing conditions is the definition of a specific spectral distribution of the sunlight (AM1.5 global). The inevitable deviations of the spectrum of artificial light sources from the standard spectrum have to be taken into account by a spectral mismatch factor. The uncertainty of this crucial correction is spectrally dependent, in most cases unknown and complex and inconvenient to evaluate. In this article a randomizing method is proposed which allows one to calculate the uncertainty of the mismatch factor from the uncertainties of the input parameters determined with high spectral resolution. Based on a range of different spectral responses of solar cells on the one hand and variations of the solar simulator spectral distribution on the other, we are able to generalize the results to a broad set of measurement configurations. A sensitivity analysis reveals the crucial wavelength regions and thus allows the systematic optimization of simulator spectra and selection of reference cells. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
10.
Steve M. Rohde 《International Journal of Mechanical Sciences》1976,18(2):95-101
The descent of a tread element of a tire rolling on a pavement on which a thin viscous fluid film is present is modeled. The tread element is assumed to be flat or curved and the pavement is assumed to possess a microtexture. Asymptotic results for the load supported by the tread element and the descent time are derived for different texture patterns. It is shown that the texture pattern as well as amplitude can significantly change the performance from that predicted by a smooth pavement assumption. 相似文献