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The results show that the greasy fleece weight varied from 0.3 kg to 2.42 kg with an average of 0.75 kg. The fleece weight decreases according to the animal age. In fact, the factor “age” has a significant effect on the dromedary fleece weight. Average scoured yield was 96% with V% of 1.6%. This indicated that matter loss, after scouring dromedary fibres, was lower than wool and cashmere. Scoured yield did not vary between samples of varied dromedary body areas in any age. The down hair yield for the fleece of the Tunisian dromedary varies between 34% and 61% with a mean of 45%. This raises interest when compared to the cashmere yield. There is a clearly decreased dromedary down hair yield according the factor “age”. The analysis of the variance shows that the dromedary down hair yield was affected by the factors “age” and body area of the animal.

Following this work it will be possible to predict the amount of down yield in the fleece of Tunisian dromedary knowing age. Consequently, it will be possible to estimate the total amount of textile material camel from dromedary located in Tunisia.  相似文献   

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Bulletin of Engineering Geology and the Environment - The Marrakech–Agadir highway crosses mountainous areas of the Western High Atlas of Morocco with a high risk of slope instability. The...  相似文献   
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Desertification has become a global threat and caused a crisis, especially in Middle Eastern countries, such as Saudi Arabia. Makkah is one of the most important cities in Saudi Arabia that needs to be protected from desertification. The vegetation area in Makkah has been damaged because of desertification through wind, floods, overgrazing, and global climate change. The damage caused by desertification can be recovered provided urgent action is taken to prevent further degradation of the vegetation area. In this paper, we propose an automatic desertification detection system based on Deep Learning techniques. Aerial images are classified using Convolutional Neural Networks (CNN) to detect land state variation in real-time. CNNs have been widely used for computer vision applications, such as image classification, image segmentation, and quality enhancement. The proposed CNN model was trained and evaluated on the Arial Image Dataset (AID). Compared to state-of-the-art methods, the proposed model has better performance while being suitable for embedded implementation. It has achieved high efficiency with 96.47% accuracy. In light of the current research, we assert the appropriateness of the proposed CNN model in detecting desertification from aerial images.  相似文献   
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Superoxide dismutase (SOD) and catalase (CAT) activities were measured in blood from 420 individuals: control population 126, males and females, age between 50 to 93 years of age without any relevant pathology. Pathological population: 294 patients, males and females, age between 50 to 93 years of age, with some disease in the cardiovascular system and in the osteoarticular system, myoma, prostatic pathologies, Chronic Obstructive Pulmonary Disease (EPOC), and Acute Cerebral Vascular Accident (ACVA). The method of Minami and Yoshikawa (SOD) and the method of Aebi (CAT) were judged the techniques of choice for a population study. Statistical methods: ANOVA and Student's "t". 1) The results were that levels of activity for SOD and CAT were increased for women in control population, and 2) the level of activity for CAT decreases with aging. In the pathological population, we detected: 3) increased activity for SOD in cardiovascular diseases, myomas, EPOC and ACVA. 4) for CAT the level of activity decreases in cardiovascular and prostatic diseases, EPOC and ACVA. 5) while in osteoarticular diseases levels of activity for SOD and CAT were standard, but SOD level decreases with aging, for CAT in cardiovascular diseases and EPOC, too. Both enzymes work to balance the antioxidant system.  相似文献   
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We developed a variational Bayesian learning framework for the infinite generalized Dirichlet mixture model (i.e. a weighted mixture of Dirichlet process priors based on the generalized inverted Dirichlet distribution) that has proven its capability to model complex multidimensional data. We also integrate a “feature selection” approach to highlight the features that are most informative in order to construct an appropriate model in terms of clustering accuracy. Experiments on synthetic data as well as real data generated from visual scenes and handwritten digits datasets illustrate and validate the proposed approach.  相似文献   
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In this article, we present an electromagnetic study of electrically programmable graphene‐based metasurface with individual scattering control. Our investigation is based on the method of moments combined with the generalized equivalent circuit (MoM‐GEC) approach. We show that, tuning the unit cell's conductivity leads to change its input impedance and scattering matrix. So, each unit cell of the metasurface exhibits' a dynamic phase response that can be switched between 0° and ?180° by controlling high transmission and total reflection states. Based on this feature, a 1‐bit coding metasurface consisting of discrete codes of “0” and “1” is used to synthesis 3D beams. Hence, tailorable anomalous reflection and diffusion are studied under normal incidence at a fixed frequency of 3.9 THz. This survey opens new opportunities in the domain of Terahertz beam engineering and security scanner applications.  相似文献   
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We study some spectral properties of the solutions to generalized thermoelastic systems under Lord–Shulman, Green–Lindsay, and Green–Naghdi of type-II models. First, we prove that the linear operator of each model has compact resolvent and generates a C0?semigroup in an appropriate Hilbert space. We also show that there is a sequence of generalized eigenfunctions of the linear operator that forms a Riesz basis. By a detailed spectral analysis, we obtain the expressions of the spectrum and we deduce that the spectrum-determined growth condition holds. Therefore, if the imaginary axis is not an asymptote of the spectrum, we prove that the energy of each model decays exponentially to a rate determined explicitly by the physical parameters. Finally, some simulations are given for each model to support our results.  相似文献   
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This investigation analyses the behaviour of a turbulent thermal plume evolving in a neutral environment and in interaction with its surrounding material. The thermal plume is created by a rectangular hot source. This source is placed at the entry of a vertical parallelepipedic canal opened at the ends. Firstly, we studied the behaviour of a free thermal plume. The flow visualization and the analysis of the thermal and dynamic fields enabled us to detect the existence of two zones during the vertical evolution of the plume. A first zone of plume development followed by a zone of established turbulence. Secondly, we described the structure of a thermal plume produced by the same source inside the vertical canal. In this case the experimental results show clearly a change of the turbulent structure of the flow in comparison with the free plume. This difference is especially characterized by the appearance of a supplementary zone just above the source that is added to the two zones described previously. In addition, the comparison of the two studied configurations showed that the structure of the plume is narrowly affected by the confinement.In order to better define the fine structure of the flow, the temperature fluctuations spectra are analyzed. This spectral analysis enables us to show the fast destruction of the big structures vortexes by the confinement effect to give a smaller structure.  相似文献   
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