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1.
The main objective of this study is to explore the utility of a neural network-based approach in hand gesture recognition. The proposed system presents two recognition algorithms to recognize a set of six specific static hand gestures, namely open, close, cut, paste, maximize, and minimize. The hand gesture image is passed through three stages: preprocessing, feature extraction, and classification. In the first method, the hand contour is used as a feature that treats scaling and translation of problems (in some cases). However, the complex moment algorithm is used to describe the hand gesture and to treat the rotation problem in addition to scaling and translation. The back-propagation learning algorithm is employed in the multilayer neural network classifier. The second method proposed in this article achieves better recognition rate than the first method.  相似文献   
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Hypoglycemia, as a complication of type 2 diabetes (T2D), causes increased morbidity and mortality but the physiological response underlying hypoglycemia has not been fully elucidated. Small noncoding microRNA (miRNA) have multiple downstream biological effects. This pilot exploratory study was undertaken to determine if induced miRNA changes would persist and contribute to effects seen 24 h post-hypoglycemia. A parallel, prospective study design was employed, involving T2D (n = 23) and control (n = 23) subjects. The subjects underwent insulin-induced hypoglycemia (2 mmol/L; 36 mg/dL); blood samples were drawn at baseline, upon the induction of hypoglycemia, and 4 h and 24 h post-hypoglycemia, with a quantitative polymerase chain reaction analysis of miRNA undertaken. The baseline miRNAs did not differ. In the controls, 15 miRNAs were downregulated and one was upregulated (FDR < 0.05) from the induction of hypoglycemia to 4 h later while, in T2D, only four miRNAs were altered (downregulated), and these were common to both cohorts (miR-191-5p; miR-143-3p; let-7b-5p; let-7g-5p), correlated with elevated glucagon levels, and all were associated with energy balance. From the induction of hypoglycemia to 24 h, 14 miRNAs were downregulated and 5 were upregulated (FDR < 0.05) in the controls; 7 miRNAs were downregulated and 7 upregulated (FDR < 0.05) in T2D; a total of 6 miRNAs were common between cohorts, 5 were downregulated (miR-93-5p, let-7b-5p, miR-191-5p, miR-185-5p, and miR-652-3p), and 1 was upregulated (miR-369-3p). An ingenuity pathway analysis indicated that many of the altered miRNAs were associated with metabolic and coagulation pathways; however, of the inflammatory proteins expressed, only miR-143-3p at 24 h correlated positively with tumor necrosis factor-α (TNFa; p < 0.05 and r = 0.46) and negatively with toll-like receptor-4 (TLR4; p < 0.05 and r = 0.43). The MiRNA levels altered by hypoglycemia reflected changes in counter-regulatory glucagon and differed between cohorts, and their expression at 24 h suggests miRNAs may potentiate and prolong the physiological response. Trial registration: ClinicalTrials.gov NCT03102801.  相似文献   
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Introduces a new method for fabricating capacitive micromachined ultrasonic transducers (CMUTs) that uses a wafer bonding technique. The transducer membrane and cavity are defined on an SOI (silicon-on-insulator) wafer and on a prime wafer, respectively. Then, using silicon direct bonding in a vacuum environment, the two wafers are bonded together to form a transducer. This new technique, capable of fabricating large CMUTs, offers advantages over the traditionally micromachined CMUTs. First, forming a vacuum-sealed cavity is relatively easy since the wafer bonding is performed in a vacuum chamber. Second, this process enables better control over the gap height, making it possible to fabricate very small gaps (less than 0.1 /spl mu/m). Third, since the membrane is made of single crystal silicon, it is possible to predict and control the mechanical properties of the membrane to within 5%. Finally, the number of process steps involved in making a CMUT has been reduced from 22 to 15, shortening the device turn-around time. All of these advantages provide repeatable fabrication of CMUTs featuring predictable center frequency, bandwidth, and collapse voltage.  相似文献   
5.
Oat has been recognized as a healthy food for a long time. In this study, physicochemical analysis including, moisture, pH, ash, fibres, proteins, starch, carbohydrates, some minerals, sugars, fatty acids, sterols, total phenolic, and flavonoid contents of four Moroccan Oat varieties (Amlal, Tissir, Zahri and Ghali) were investigated. Additionally, starch morphology has been described according to scanning electron microscopy, and viscosity as measured on a rotary rheometer, increased with stabilization time. Furthermore, Oat extracts were analyzed with regard to their antioxidant activities using DPPH radicals’ cation, Trolox equivalent antioxidant capacity and ferric reducing/antioxidant power. Results from this investigation demonstrated that Moroccan Oat varieties constitute an interesting supplement of natural antioxidants, especially phenolic compounds. Moreover, potassium was the main mineral in Oat seeds (1628.17–2541.52 mg/Kg); also, the oleic, linoleic, and palmitic acids were the dominant fatty acids. While the major sterols were, β-sitosterol, Δ-5-avenasterol and campesterol. Finally, sugar analysis by HPLC-RI indicate that sucrose content was higher than glucose and fructose respectively, and that Ghali and Amlal varieties exhibit an important total sugars levels. Those results highlight the possible contributions of Oat seeds to nutritional therapy.  相似文献   
6.
Main possible honey fraud is the addition of various sugar syrups. But, there are also other types of fraud, such as deception on the geographical and/or botanical origin product. Providing a product of the hive with full authenticity is therefore crucial for the preservation of beekeeping. In this pursuit, voltammetric electronic tongue (VE-tongue) was employed to classify honey samples from different geographical and botanical origins. Furthermore, VE-tongue was used to detect adulterants such as glucose syrup (GS) and saccharose syrup (SS) in honey. The data obtained were analyzed by three-pattern recognition techniques: principal component analysis (PCA), support vector machines (SVMs), and hierarchical cluster analysis (HCA). These methods enabled the classification of 18 honeys of different geographical origins and 7 honeys of different botanical origins. Excellent results were obtained also in the detection of adulterated honey. Therefore, this simple method based on VE-tongue could be useful in the honey packaging and commercialization industry.  相似文献   
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Background: This is a first systematic review summarizing 43 years of research from 36 countries for the assessment of cadmium in breast milk, a suitable matrix in human biomonitoring. Objectives: To report from the published literature the levels of cadmium in breast milk, and the affecting factors causing increase in cadmium concentrations. In addition, to gather several quantitative data that might be useful to evaluate the international degrees of maternal and infant exposure. Methods: We reviewed the literature published between 1971 and 2014, available on Pubmed, Science Direct, and Google Scholar, reporting quantitative data about cadmium levels in human breast milk. Information about the aim of the study, name of the country, period of collection of samples, size of samples, sampling method, time of lactation, mother's age, area of residence, cadmium concentration, and other data were extracted. Results: Sixty-seven studies were selected and included in this systematic review. Some concentrations greatly exceed the limit set by the World Health Organization (WHO); however, about 50% of the studies had less than 1 µg/L cadmium concentration (recommended by the WHO); as well as many factors have shown their implication in breast milk contamination. Conclusions: Breast milk is a pathway of maternal excretion of cadmium. It is also a biological indicator of the degree of environmental pollution and cadmium exposure of the lactating woman and the nourished infant. Therefore, preventive measures and continuous monitoring are necessary.  相似文献   
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Summary Different alkyl sulfides (dimethylsulfide, ditertiobutylsulfide and diphenylsulfide) were investigated in the polymerization of 1,3-pentadiene initiated by aluminum trichloride in polar solvent in order to control the polymerization and to study the interaction between the electron donor and the active species. Thus, it was found that dimethylsulfide totally inhibited the polymerization, while thanks to its steric hindrance the polymerization occurred in the presence of ditertiobutylsulfide. However, for this electron donor, a transfer activity was evidenced at room temperature and at 0°C, which contributes to prevent the control of the polymerization. Diphenylsulfide stabilizes a little the active centers with nearly no transfer reaction. However in the studied experimental conditions, the stabilization was not sufficient to obtain a living polymerization.  相似文献   
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