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One of the leading causes of mortality worldwide is liver cancer. The earlier the detection of hepatic tumors, the lower the mortality rate. This paper introduces a computer-aided diagnosis system to extract hepatic tumors from computed tomography scans and classify them into malignant or benign tumors. Segmenting hepatic tumors from computed tomography scans is considered a challenging task due to the fuzziness in the liver pixel range, intensity values overlap between the liver and neighboring organs, high noise from computed tomography scanner, and large variance in tumors shapes. The proposed method consists of three main stages; liver segmentation using Fast Generalized Fuzzy C-Means, tumor segmentation using dynamic thresholding, and the tumor's classification into malignant/benign using support vector machines classifier. The performance of the proposed system was evaluated using three liver benchmark datasets, which are MICCAI-Sliver07, LiTS17, and 3Dircadb. The proposed computer adided diagnosis system achieved an average accuracy of 96.75%, sensetivity of 96.38%, specificity of 95.20% and Dice similarity coefficient of 95.13%.  相似文献   
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This study aims at assessing the technical and economic benefits of refurbishing existing public housing villas in the UAE. Four representative federal public housing villas built between 1980s and 2010s were modeled and analyzed. The Integrated Environmental Solutions-Virtual Environment (IES-VE) energy modeling software was used to estimate the energy consumption and savings due to different refurbishment configurations applied to the villas. The refurbishment technical configurations were based on the UAE’s Estidama green buildings sustainability assessment system. The refurbishment configurations include upgrading three elements: the wall and roof insulation as well as replacing the glazing. The annual electricity savings results indicated that the most cost-efficient refurbishment strategy is upgrading of wall insulation (savings up to 20.8 %) followed by upgrading the roof’s insulation (savings up to 11.6 %) and lastly replacing the glazing (savings up to 3.2 %). When all three elements were refurbished simultaneously, savings up to 36.7 % were achieved (villa model 670). The savings translated to CO2 emission reduction of 22.6 t/year. The simple and discounted payback periods for the different configurations tested ranged between 8 and 28 and 10 and 50 years, respectively.  相似文献   
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High-performance liquid chromatographic method with diode-array detection (HPLC–DAD) was optimised and validated for determination of tetracyclines (TCs) residue in chicken meat and liver through evaluating each step of various methods. The principle steps involved ultrasonic-assisted extraction of TCs from chicken samples by 2 ml of 20% trichloroacetic acid and citrate buffer (pH 4) which gave a clearer supernatant and high recovery, followed by centrifugation and purification on SPE (Strata C18-E cartridge) using 10 ml of 0.01 M methanolic oxalic acid for TCs elution. Separation was on reversed-phase column (Nuclosil 100 C18, 25 cm × 4.6 mm ID, 5 μ) by multisteps gradient elution which provided a better chromatographic peak resolution and the late eluting peaks were as sharp as those eluting earlier. Monitoring was at 351 nm which gave a higher detector response factor. Validity study of the method revealed that all obtained calibration curves showed good linearity (r2 > 0.999) over the range of 50–5000 ng. Sensitivity was found to be 1.44, 1.90, 0.95 and 1.23 ng for OTC, TC, CTC and DC, respectively. Accuracy was in the range of 71.88–92.44.3% and 68.88–84.84% for meat and liver, respectively. Precision was lower than 10% in all cases indicating that the method can be used as a validated method. Limit of detection (LOD) was found to be 4.4, 5, 13 and 10 ng for OTC, TC, CTC and DC, respectively. The corresponding values of limit of quantitation (LOQ) were 10, 13, 27 and 22 ng.  相似文献   
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OBJECTIVE: The aim of this study was to assess quantitatively structural changes in myelin content occurring during demyelination and remyelination by magnetization transfer imaging (MTI). MATERIALS AND METHODS: In a reversible model of demyelination with no axonal loss, mice intoxicated by cuprizone were studied by MTI in vivo at 9.4 T. MRI data were compared to histopathological examinations. RESULTS: Data revealed that the magnetization transfer ratio (MTR) decreased significantly during demyelination and increased during remyelination with strong correlation to the myelin content (r = 0.79, P = 0.01). CONCLUSIONS: This study demonstrated that MTR is a sensitive and reproducible quantitative marker to assess myelin loss and repair. This may lead to in vivo monitoring of therapeutic strategies promoting remyelination.  相似文献   
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Wireless Personal Communications - In this paper, an exact performance analysis for the hybrid radio frequency/free space optical (RF/FSO) communication system based on receiver diversity combining...  相似文献   
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The protective films developed on copper by anodic polarization in a borate-buffered solution containing benzotriazole (BTAH), 1-hydroxybenzotriazole (BTAOH) or 3-amino 1, 2, 4-triazole (ATA) have been characterized using coulometric experiments and an electrochemical quartz crystal microbalance (EQCM). The combination of these two techniques has allowed the CuO and Cu2O layers and the cuprous-organic layer to be analyzed quantitatively. In the presence of BTAOH, the oxide layers were very similar to those formed in inhibitor-free solution and BTAOH appeared to be adsorbed on the oxide film. In the presence of BTAH, a thick Cu2O film was covered by a Cu-BTA film containing 8% Cu+ ions. Cupric oxide appeared on Cu2O areas uncovered by Cu-BTA. In the presence of ATA, the Cu2O layer was very thin and the greater part of Cu+ ions (75%) was involved in a thick Cu-ATA film.  相似文献   
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