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本文首先概述了目标提取的诸多算法,然后针对复杂背景下的运动目标提取,重点研究了帧间图像差分算法,设计了一种目标提取算法模型,最后提出了一种基于对象的目标提取方法并进行了仿真实验。  相似文献   
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The criteria for cis-trans photoisomerization of eriochrome black-T (EBT) in the flat-plate collector system, which consists of endoergic photochemical reaction, has been investigated. The efficiencies of this collector in both summer and winter have been compared with blank (distilled water only) and colored liquid (non-isomer-dye-absorbing in the same wavelength range). The photochemical storage efficiency was found to be higher in winter than in summer. The optimum efficiency for this photoisomerization-thermal reversion cycle was found by varying with the pumping rate of the liquid to match the value of rate constant of cis to trans reaction. The stability of (EBT) has been studied under different environmental conditions.  相似文献   
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The Journal of Supercomputing - Cloud users can acquire resources in the form of virtual machines (VMs) instances for computing. These instances can be on-demand, reserved and spot instances....  相似文献   
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Cloud computing is the delivery of on‐demand computing resources. Cloud computing has numerous applications in fields of education, social networking, and medicine. But the benefit of cloud for medical purposes is seamless, particularly because of the enormous data generated by the health care industry. This colossal data can be managed through big data analytics, and hidden patterns can be extracted using machine learning procedures. In particular, the latest issue in the medical domain is the prediction of heart diseases, which can be resolved through culmination of machine learning and cloud computing. Hence, an attempt has been made to propose an intelligent decision support model that can aid medical experts in predicting heart disease based on the historical data of patients. Various machine learning algorithms have been implemented on the heart disease dataset to predict accuracy for heart disease. Naïve Bayes has been selected as an effective model because it provides the highest accuracy of 86.42% followed by AdaBoost and boosted tree. Further, these 3 models are being ensembled, which has increased the overall accuracy to 87.91%. The experimental results have also been evaluated using 10,082 instances that clearly validate the maximum accuracy through ensembling and minimum execution time in cloud environment.  相似文献   
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A new technique concerning the evaluation of multiple stress singularity orders of a V-notch with the boundary element method is proposed. For linear elastic material, the asymptotic displacement field in a V-notch tip region is expressed as a series expansion with respect to the radial coordinate from the V-notch tip. The series expansion of the asymptotic field is then substituted into the boundary integral equation established on the V-notch. By boundary element discretization, the boundary integral equation is transformed into an eigen-equation with respect to the stress singularity orders. Hence the eigen-values, which are the singularity orders, can be obtained simultaneously by solving the eigen-equation. An evident feature of the present method is that the real and complex singularity orders together with the non-singularity ones can be obtained at the same time.  相似文献   
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Abstract

Combustion sources have been shown to directly emit particles smaller than 10?nm. The emission of 1-3?nm particles from biofuel or fossil fuel cookstoves has not been studied previously, nor have the radiative impacts of these emissions been investigated. In this work, emissions (number of particles) were measured during a water boiling test performed on five different cookstoves (three-stone fire, rocket elbow, gasifier, charcoal, and liquified petroleum gas [LPG]) for particle diameters between ~1 and ~1000?nm. We found significant emissions of particles smaller than 10?nm for all cookstoves (>5?×?1015 # kg-fuel?1). Furthermore, cleaner (e.g., LPG) cookstoves emitted a larger fraction of sub-10?nm particles (relative to the total particle counts) than traditional cookstoves (e.g., three-stone fire). Simulations performed with the global chemical transport model GEOS-Chem-TOMAS that were informed by emissions data from this work suggested that sub-10?nm particles were unlikely to significantly influence number concentrations of particles with diameters larger than 80?nm that can serve as cloud condensation nuclei (CCN) (<0.3%, globally averaged) or alter the cloud-albedo indirect effect (absolute value <0.005?W m?2, globally averaged). The largest, but still relatively minor, localized changes in CCN-relevant concentrations (<10%) and the cloud-albedo indirect effect (absolute value <0.5?W m?2) were found in large biofuel combustion source regions (e.g., Brazil, Tanzania, Southeast Asia) and in the Southern Ocean. Enhanced coagulation-related losses of these sub-10?nm particles at sub-grid scales will tend to further reduce their impact on particle number concentrations and the aerosol indirect effect, although they might still be of relevance for human health.

Copyright © 2020 American Association for Aerosol Research  相似文献   
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Many mould strains, in particular Aspergillus and/or Penicillium, are able to develop on olive and produce ochratoxin A (OTA) and/or citrinin (CIT) and/or aflatoxin B (AFB) after harvest, during drying and storage of olives. The development of fungi on olives is responsible for the reduction of nutritional quality of olive because they can disturb the synthesis of the fatty acids. OTA, CIT and AFB are particularly dangerous for health, inducing cancer of urinary tracts or liver carcinoma. In this study, ten olive samples bought at retailer and at supermarket in Morocco were analyzed for their OTA, CIT and AFB contents. These three mycotoxins were extracted simultaneously by a method based on solvent partition validated in-house, then separated by HPLC coupled to a fluorescence detector. All olive samples contain OTA ranging from LOQ to 1.02 microg/kg. Respectively, 50 and 25% from retailer and supermarket samples were contaminated by more than 0.65 microg/kg. In addition, 80% of olive samples contained CIT above LOD, and 100% of olive tested contained AFB above 0.5 microg/kg. As simultaneous presence of these toxins increases toxic risks, it is thus essential to have a good control of the conservation of olives after harvest.  相似文献   
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