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131.
The use of machine learning tools in biological data analysis is increasing gradually. This is mainly because the effectiveness of classification and recognition systems has improved in a great deal to help medical experts in diagnosing. In this paper, we investigate the performance of an artificial immune system based k-nearest neighbors algorithm with and without cross-validation in a class of imbalanced problems from bioinformatics field. Furthermore, we used an unsupervised artificial immune system algorithm for reduction training data dimension and k-nearest neighbors algorithm for classification purpose. The conducted experiments showed the effectiveness of the proposed schema. By selecting the E. coli database, we could compare our classification accuracy with other methods which were presented in the literature. The proposed hybrid system produced much more accurate results than the Horton and Nakai's proposal [P. Horton, K. Nakai, A probabilistic classification system for predicting the cellular localization sites of proteins, in: Proceedings of the 4th International Conference on Intelligent Systems for Molecular Biology, AAAI Press, St. Louis, 1996, pp. 109–115; P. Horton, K. Nakai, Better prediction of protein cellular localization sites with the k-nearest neighbors classifier, in: Proceedings of Intelligent Systems in Molecular Biology, Halkidiki, Greece, 1997, pp. 368–383]. Besides the accuracy improvement, one of the important aspects of the proposed methodology is the complexity. As the artificial immune system provided data reduction, the training complexity of the proposed system is considerably low against the k-nearest neighbors classifier. 相似文献
132.
The user‐oriented design is the most important competition issue in today's market. In recent years, user‐oriented design (i.e., usability) has become expected, particularly in electronic devices. Usability considers high user satisfaction in conjunction with user performance. Usability of electronic products is essential for high customer satisfaction as well as product life cycles in companies. Therefore, MP3 players were selected among the electronic products. Designing usable MP3 players is extremely important for users who have close interaction with them. In this study, MP3 players of different types and sizes were selected and their usability evaluated. The usability criteria used in the MP3 players' evaluation were divided into two major categories: performance and emotional expectations. The alternatives were ranked with fuzzy multi‐criteria decision‐making methods, namely, Fuzzy TOPSIS (FTOPSIS), Fuzzy Analytic Hierarchy Process (FAHP), and Fuzzy Axiomatic Design Theory (FADT), and the results were compared. Although the same decision matrices and data obtained from semantic differential experiment were used for all fuzzy multi‐criteria decision‐making methods, it is shown that different rankings were obtained. © 2012 Wiley Periodicals, Inc. 相似文献
133.
The lipophilic extracts of a number of edible plants, including Anthemis tinctoria var. tinctoria, A. austriaca, Carduus acanthoides, C. nutans, Cirsium hypoleucum, Cynara scolymus (Asteraceae), Silene vulgaris (Caryophyllaceae), Ajuga chamaepitys ssp. chia var. ciliata (Lamiaceae), Lappula barbata (Boraginaceae), Rumex obtusifolius ssp. subalpinus (Polygonaceae), Digitalis lamarckii (Scrophulariaceae), and Sedum hispanicum (Crassulaceae) were tested against DNA virus Herpes simplex (HSV) and RNA virus Parainfluenza (PI-3) using Madin-Darby bovine kidney and Vero cell lines, and also analysed by capillary gas chromatography–mass spectrometry (GC–MS). Most of the extracts exerted quite appreciable antiviral effect against both viruses, as compared to acyclovir and oseltamivir. Cytotoxicity of the extracts was also determined as maximum non-toxic concentrations (MNTCs). Most of the extracts were found to be rich in saturated fatty acids. No correlation was found between antiviral activity and fatty acid contents of the extracts. 相似文献
134.
Didem Deliorman‐Orhan Sezer Şenol Murat Kartal Ilkay Orhan 《Journal of the science of food and agriculture》2009,89(5):809-814
BACKGROUND: Antioxidant capacity of the chloroform, ethyl acetate, n‐butanol and water fractions of the aerial parts of Calluna vulgaris (L.) Hull (Ericaceae) has been assessed in this study. Antioxidant capacity of the plant was screened by assays of 2,2‐diphenyl‐β‐picrylhydrazyl, superoxide anion and hydrogen peroxide scavenging, metal‐chelating activity and reducing power. Butylated hydroxyanisole was used as reference in all assays; ethylene diamine tetraacetic acid was also used as reference in the assay of metal‐chelating activity. Total phenolic contents of the fractions were determined by the Folin–Ciocalteu method. RESULTS: Liquid chromatography/diode array detection/mass spectrometry was used for phytochemical identification of the fractions. Kaempferol‐3‐O‐β‐D ‐galactoside was found to be the major constituent in the ethyl acetate fraction (37.1 ± 0.9%), followed by the n‐butanol fraction (4.6 ± 0.1%). High occurrence of antioxidant capacity, with the exception of metal‐chelating activity, was observed in the ethyl acetate and chloroform fractions as well as in kaempferol‐3‐O‐β‐D ‐galactoside. CONCLUSION: Calluna vulgaris and its major flavonoid, kaempferol‐3‐O‐β‐D ‐galactoside, show high antioxidant capacity in various assays. As far as is known, this is the first report on antioxidant capacity of C. vulgaris and its major flavonoid. Copyright © 2009 Society of Chemical Industry 相似文献
135.
Statistical metrics for assessing the quality of wind power scenarios for stochastic unit commitment 下载免费PDF全文
In power systems with high penetration of wind generation, probabilistic scenarios are generated for use in stochastic formulations of day‐ahead unit commitment problems. To minimize the expected cost, the wind power scenarios should accurately represent the stochastic process for available wind power. We employ some statistical evaluation metrics to assess whether the scenario set possesses desirable properties that are expected to lead to a lower cost in stochastic unit commitment. A new mass transportation distance rank histogram is developed for assessing the reliability of unequally likely scenarios. Energy scores, rank histograms and Brier scores are applied to alternative sets of scenarios that are generated by two very different methods. The mass transportation distance rank histogram is best able to distinguish between sets of scenarios that are more or less calibrated according to their bias, variability and autocorrelation. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
136.
Geological studies indicate that the most important geothermal systems of western Turkey are located in the major grabens of the Menderes Metamorphic Massif, while those that are associated with local volcanism are more common in the central and eastern parts of the country. The present (2008) installed geothermal power generation capacity in Turkey is about 32.65 MWe, while that of direct use projects is around 795 MWt. Eleven major, high-to-medium enthalpy fields in western part of the country have 570 MWe of proven, 905 MWe of probable and 1389 MWe of possible geothermal reserves for power generation. In spite of the complex legal issues related to the development of Turkey's geothermal resources, their use is expected to increase in the future, particularly for electricity generation and for greenhouse heating. 相似文献
137.
Tas DO Thomson IN Löffler FE Pavlostathis SG 《Environmental science & technology》2006,40(14):4467-4472
The microbial reductive dechlorination kinetics of pentachloroaniline (PCA) and less chlorinated anilines (CAs) were investigated with a mixed, fermentative/ methanogenic culture. Batch dechlorination assays were performed with all available CAs at an initial concentration of 3 microM, and an incubation temperature of 22 degrees C. Dechlorination of PCA, two tetrachloroanilines (2,3,4,5- and 2,3,5,6-TeCA), five trichloroanilines (2,3,4-, 2,3,5-, 2,4,5-, 2,4,6-, and 3,4,5-TrCA), and one dichloroaniline (3,5-DCA; low extent) was observed but none of the five remaining dichloroanilines and three monochloroanilines were dechlorinated by the enrichment culture during batch assays. The dechlorination rates (k') and half-saturation coefficients (Kc) were measured using nonlinear regression based on the integrated Michaelis-Menten equation under conditions of electron donor saturation and assuming constant biomass concentration over the relatively short batch incubation period. At an initial concentration of CAs of about 3 microM, the values of k' and Kc ranged from 0.25 to 1.19 microM/day and from 0.11 to 1.72 microM, respectively, corresponding to half-lives in the range of 1.5-8.5 days. Model simulations of the sequential dechlorination reactions based on a branched-chain Michaelis-Menten model and using independently measured k' and Kc values matched the experimental data very well. 相似文献
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140.
Aydogan Ozdamar Necdet Ozbalta Alp Akin E. Didem Yildirim 《Renewable & Sustainable Energy Reviews》2005,9(6):624-637
In this work, a combined system which is produced electrical energy from both solar radiation via solar cells and wind energy by using wind turbine was studied. For wind energy, measurements of wind velocities at 12 m height were taken. Then, these values were calculated for 42 m by using Hellmann equation. After that, wind energy converted to the electrical energy. However, value of solar radiation from solar cells was taken at the optimum slope angle of collector which provided higher energy production for each 1 h during this application. Thus, obtained data from each system were used together for finding total energy. For this study, measurements, which would be used in calculation of wind energy and solar energy were taken for four years between 1995 and 1998 in Izmir. As a result, energy of the combined system could support each other when one of them produces energy insufficiently. 相似文献