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41.
Fuzzy Genetic Approach for Modeling Reference Evapotranspiration 总被引:1,自引:0,他引:1
Ozgur Kisi 《Canadian Metallurgical Quarterly》2010,136(3):175-183
This study investigates the ability of fuzzy genetic (FG) approach in modeling of reference evapotranspiration (ET0). The daily climatic data, solar radiation, air temperature, relative humidity, and wind speed from three stations, Windsor, Oakville and Santa Rosa, in central California, are used as inputs to the FG models to estimate ET0 obtained using the FAO-56 Penman-Monteith equation. A comparison is made between the estimates provided by the FG and those of the following empirical models: the California Irrigation Management System Penman, Hargreaves, Ritchie, and Turc methods. The FG results are also compared with the artificial neural networks. Root-mean-square errors (RMSE), mean-absolute errors (MAE), and correlation coefficient statistics are used as comparing criteria for the evaluation of the models’ performances. The comparison results reveal that the FG models are superior to the ANN and empirical models in modeling ET0 process. For the Windsor, Oakville, and Santa Rosa stations, it was found that the FG models with RMSEW = 0.138, MAEW = 0.098, and RW = 0.999; RMSEO = 0.144, MAEO = 0.102, and RO = 0.999; and RMSES = 0.167, MAES = 0.115, and RS = 0.998 in test period is superior in modeling daily ET0 than the other models, respectively. 相似文献
42.
Performance Evaluation of ANN and ANFIS Models for Estimating Garlic Crop Evapotranspiration 总被引:2,自引:0,他引:2
Hamid Zare Abyaneh Alireza Moghaddam Nia Maryam Bayat Varkeshi Safar Marofi Ozgur Kisi 《Canadian Metallurgical Quarterly》2011,137(5):280-286
Estimation of evapotranspiration (ET) is necessary in water resources management, farm irrigation scheduling, and environmental assessment. Hence, in practical hydrology, it is often necessary to reliably and consistently estimate evapotranspiration. In this study, two artificial intelligence (AI) techniques, including artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS), were used to compute garlic crop water requirements. Various architectures and input combinations of the models were compared for modeling garlic crop evapotranspiration. A case study in a semiarid region located in Hamedan Province in Iran was conducted with lysimeter measurements and weather daily data, including maximum temperature, minimum temperature, maximum relative humidity, minimum relative humidity, wind speed, and solar radiation during 2008–2009. Both ANN and ANFIS models produced reasonable results. The ANN, with 6-6-1 architecture, presented a superior ability to estimate garlic crop evapotranspiration. The estimates of the ANN and ANFIS models were compared with the garlic crop evapotranspiration (ETc) values measured by lysimeter and those of the crop coefficient approach. Based on these comparisons, it can be concluded that the ANN and ANFIS techniques are suitable for simulation of ETc. 相似文献
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Ozgur E. Akman Steven Watterson Andrew Parton Nigel Binns Andrew J. Millar Peter Ghazal 《Journal of the Royal Society Interface》2012,9(74):2365-2382
The gene networks that comprise the circadian clock modulate biological function across a range of scales, from gene expression to performance and adaptive behaviour. The clock functions by generating endogenous rhythms that can be entrained to the external 24-h day–night cycle, enabling organisms to optimally time biochemical processes relative to dawn and dusk. In recent years, computational models based on differential equations have become useful tools for dissecting and quantifying the complex regulatory relationships underlying the clock''s oscillatory dynamics. However, optimizing the large parameter sets characteristic of these models places intense demands on both computational and experimental resources, limiting the scope of in silico studies. Here, we develop an approach based on Boolean logic that dramatically reduces the parametrization, making the state and parameter spaces finite and tractable. We introduce efficient methods for fitting Boolean models to molecular data, successfully demonstrating their application to synthetic time courses generated by a number of established clock models, as well as experimental expression levels measured using luciferase imaging. Our results indicate that despite their relative simplicity, logic models can (i) simulate circadian oscillations with the correct, experimentally observed phase relationships among genes and (ii) flexibly entrain to light stimuli, reproducing the complex responses to variations in daylength generated by more detailed differential equation formulations. Our work also demonstrates that logic models have sufficient predictive power to identify optimal regulatory structures from experimental data. By presenting the first Boolean models of circadian circuits together with general techniques for their optimization, we hope to establish a new framework for the systematic modelling of more complex clocks, as well as other circuits with different qualitative dynamics. In particular, we anticipate that the ability of logic models to provide a computationally efficient representation of system behaviour could greatly facilitate the reverse-engineering of large-scale biochemical networks. 相似文献
46.
A hollow-fiber bundle was designed and used to deliver high-peak-power pulses from a Q-switched Nd:YAG laser. An 80 cm long bundle with a total diameter of 5.5 mm was composed of 37 glass capillaries with bore diameters of 0.7 mm. Beam-resizing optics with two lenses were used to couple the laser beam into the bundle. The measured coupling loss due to the limited aperture ratio of the bundle was 2.3 dB, and the transmission loss at wavelengths of 1064 and 532 nm was 0.3 dB. When an inert gas flowed through the bores of the capillaries, the maximum output pulse energy was 200 mJ, which was the limit of the laser used in the experiment. Hollow-fiber bundles withstand irradiation better than single hollow fibers and silica-glass optical fibers do. They are suitable for many dermatological applications because they can be used to irradiate a large area. 相似文献
47.
Ozgur Dogan Uluozlu Mustafa Tuzen Durali Mendil Bahattin Kahveci Mustafa Soylak 《Journal of hazardous materials》2009,172(1):395-399
A method for the separation and speciative determination of Cr(VI) and Cr(III) has been developed. The procedure is based on coprecipitation of Cr(III) on 3-ethyl-4-(p-chlorobenzylidenamino-4,5-dihydro-1H-1,2,4-triazol-5-one (EPHBAT) without carrier element. The Cr(III) can be selectively precipitated on EPHBAT in the pH range of 8.0–9.0, while Cr(VI) cannot be retained. Total chromium was determined after the reduction of Cr(VI) to Cr(III) with 0.5 mL of concentrated H2SO4 and 0.5 mL of ethanol. Cr(VI) concentrations were obtained as the respective differences between total chromium and Cr(III). Experiments were performed to optimize conditions, such as pH, amounts of EPHBAT, sample volume, etc. A preconcentration factor of 50-fold was achieved for Cr(III). The detection limit of the method for Cr(III) was 1.0 μg L−1. To validate the developed method, the certified reference materials (NIST SRM 1573a and GBW 0703) were analyzed. The method was applied for the speciation of chromium in spiked natural water samples with satisfactory results. 相似文献
48.
DNA-based assays offer precision in ascertaining the species/cultivar origin of agro-food products. Yet, obtaining DNA of sufficient quality and quantity is the main challenge while performing DNA-based food authentication analyses. The aim of the present work was to standardize a cost-efficient, easy-to-apply, yet effective plant oil DNA isolation protocol that allows reliable downstream PCR-based analyses. Because capillary electrophoresis (CE) separation of species/cultivar discriminating genomic fragments is a widely adopted approach in food genomics, a CE system was utilized in order to assess the performance of the proposed cetyl trimethyl ammonium bromide (CTAB)-based protocol. A plastid intergenic spacer and a nuclear olive gene were used as targets in order to evaluate the amplificability of DNA extracted with the CTAB-based protocol. The plastid barcode not only allowed assessing the reproducibility of PCR amplifications from the extracted oil DNA samples (olive, hazelnut, corn, rapeseed, cottonseed, and soybean oils) but also proved successful in discriminating all tested oil crop species based on amplified fragment length polymorphisms. Moreover, the barcode assay proved successful in correctly identifying the tested olive oil: cottonseed oil blends as admixtures of the two oil species. Thus, it was also feasible to demonstrate the potential of the barcode sequence as a discriminatory analyte to detect adulteration in plant oils. In addition, application of a CAPS (cleaved amplified polymorphic sequence) assay designed to genotype a nuclear SNP (single nucleotide polymorphism) marker resulted in the successful identification of the two single-cultivar olive oils included in the study. As a result of the present work, it was feasible to standardize a reliable and cost-efficient DNA extraction protocol that works well with both unrefined (olive and hazelnut) and refined (corn, rapeseed, cottonseed, and soybean) oils. 相似文献
49.
A study of the threshold characteristics of quantum-dot (QD) laser diodes shows how inhomogeneous broadening and p-doping influence the QD laser's temperature dependence of threshold T 0. The analysis includes the additional parameters of homogeneous broadening, quantum state populations, and threshold gain. The results show that while the source of negative T 0 can occur due to different effects, the transparency current plays a critical role in both undoped and p-doped QD lasers. Experimental trends of negative T 0 and their dependence on p-doping are replicated in the calculated results. Inhomogeneous broadening is found to play a lesser role to the transparency current in setting T 0. Homogeneous broadening is most important for uniform QDs with thermally isolated ground-state transitions. 相似文献
50.
Ethylene diamine bisborane (EDB) was synthesized in a single step as the hydrogen storage material. The synthesized compound was firstly used in the literature for the production of hydrogen gas by catalytic hydrolysis reaction. Cu, Co and Ni nanoparticles with average sizes of 75–150 nm formed in p(acrylicacid-co-vinylimidazole) hydrogel network structures were used as catalysts for the hydrolysis reaction. The effect of the parameters such as catalyst type, EDB concentration, catalyst concentration, temperature and solvent environment on the catalytic hydrolysis reaction of EDB was investigated. In the activity tests for the catalyst, it was determined that the catalyst had a loss of only 15% in activity even at the end of 5 cycles. The activation energies of hydrolysis reaction were calculated as 39.42 kJmol–1, 44.77 kJmol–1 and 47.48 kJmol–1 for Cu, Co and Ni hydrogel composite catalyst, respectively. 相似文献