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1.
This paper presents robust empirical path loss models to characterize indoor propagation for access point (AP) deployed at different heights. The proposed models are developed with wireless local area network infrastructure at 2.4 GHz. The models are backed by extensive received signal strength (RSS) measurements acquired in line of sight and obstructed line of sight regions. The models are developed for two conditions, viz; quasi realistic and realistic RSS measurements. The quasi realistic measurements are taken after suppressing human intervention and electrical interferences to minimum. While the realistic RSS measurements are made in presence of all the human interventions and electrical interferences. The shadow fading component for both quasi realistic and realistic conditions is statistically modeled with the dependency on AP height. The proposed technique can be applied with higher confidence level to the buildings with similar construction features where RSS measurements are made upon. The results reveal that the performance of the proposed propagation models is significantly higher than the existing International Telecommunication Union-path loss model. The results also demonstrate that the realistic path loss model is more robust than the quasi realistic model.  相似文献   
2.
Today, the dramatic changes in types of food consumed have led to an increased burden of chronic diseases. Therefore, the emphasis of food research is not only to ensure quality food that can supply adequate nutrients to prevent nutrition related diseases, but also to ensure overall physical and mental-health. This has led to the concept of functional foods and nutraceuticals (FFNs), which can be ideally produced and delivered through plants. Metabolomics can help in getting the most relevant functional information, and thus has been considered the greatest –OMICS technology to date. However, metabolomics has not been exploited to the best potential in plant sciences. The technology can be leveraged to identify the health promoting compounds and metabolites that can be used for the development of FFNs. This article reviews (i) plant-based FFNs-related metabolites and their health benefits; (ii) use of different analytic platforms for targeted and non-targeted metabolite profiling along with experimental considerations; (iii) exploitation of metabolomics to develop FFNs in plants using various biotechnological tools; and (iv) potential use of metabolomics in plant breeding. We have also provided some insights into integration of metabolomics with latest genome editing tools for metabolic pathway regulation in plants.  相似文献   
3.
Wireless Personal Communications - Indoor Wireless Local Area Network location estimation using received signal strength indication (RSSI) has gained importance due to its low cost and...  相似文献   
4.
The present study revealed a facile, ultrasound assisted ceria nanoparticle synthesis route by the reduction of cerium nitrate hexahydrate in different solvents at room temperature. The different solvents employed were methanol (MeOH), ethylene glycol (EG), water (aq) and isopropyl alcohol (IPA). The ceria nanoparticles were synthesized without the use of any capping agent in 20?min. The yield obtained was around 90% for the synthesized ceria samples. As synthesized ceria nanoparticles were characterized by X-ray diffraction (XRD), Field emission gun scanning electron microscopy (FEG-SEM), Brunauer Emmett Teller (BET) and zeta (ζ) potential in order to determine the influence of solvent on the physical properties of ceria nanoparticles. All the ceria samples illustrated a predominant spherical shape with the size in the range of 5–20?nm. It was found that interaction of the solvent with ceria nanoparticles in the presence of ultrasound plays an important role in modulating crystallite size, surface charge and its adsorption performance for a xylene milling yellow 6G dye. Among all the sonicated ceria samples, IPA mediated ceria exhibited highest positive zeta potential and hence was found to be proficient for the complete removal of dye in 15?min. Furthermore, the adsorption of the yellow milling dye on the surface of (IPA mediated) sonicated ceria sample has shown to follow pseudo-first order kinetic model. The non-sonicated sample (prepared in MeOH solvent without ultrasound) shows negligible dye adsorption while sonicated sample reveals 50% removal of XMY dye due to the difference in zeta potential values resulted from the cavitation effects.  相似文献   
5.
This paper presents numerical simulations of the response of a biological cell during freezing. The cell is modeled as an aqueous salt solution surrounded by a semi-permeable membrane. The concentration and temperature fields both inside and outside a single cell are computed taking into account heat transfer, mass diffusion, membrane transport, and evolution of the solidification front. The external ice front is computed for both stable and unstable growth modes. It is shown that for the particular geometry chosen in this study, the instabilities on the front and the diffusional transport have only modest effects on the cell response. For the cooling conditions, solute and cell property parameters used, the low Peclet regime applies. The computational results are therefore validated against the conventional membrane-limited transport (Mazur) model. Good agreement of the simulation results with the Mazur model are obtained for a wide range of cooling rates and membrane permeabilities. A spatially non-isothermal situation is also considered and shown to yield significant differences in the cell response in comparison to the isothermal case.  相似文献   
6.
BACKGROUND: The purpose of the present study was to evaluate nutritional and toxicological aspects of rice grown in fly ash amended soils. Rice was grown on soils with fly ash (200 t ha?1) and without fly ash at two different geographical locations of India. RESULTS: One kilogram each of 36 samples randomly collected from three replicates of rice grown with and without fly ash was subjected to various analytical techniques to determine the nutrient composition, mineral and heavy metal content. Moisture, protein and ash content of the rice samples showed no difference between fly ash treated and controls. Similar observations were also made on trace and heavy elements. Further, the rice grown on soils treated with fly ash was incorporated in the diet at 90% level and was fed to Wistar/NIN rats for 26 weeks for carrying out protein and toxicological evaluation. CONCLUSION: Results indicated that there is no difference between rice samples grown in soils with or without fly ash. Studies also clearly indicated that there were no adverse effects on hematological, biochemical or histopathological parameters when rice was fed to rats for 6 months. This indicates that rice grown on fly ash treated soils may be safe for human consumption. Copyright © 2012 Society of Chemical Industry  相似文献   
7.
This work presents a level‐set–based sharp interface technique to simulate the evolution of damage in ductile materials under high velocity impact conditions. The level‐set method is adopted to track all interfaces including damage zones within the materials. Two types of damage are considered, ie, the creation of spall zones due to damage accumulation in homogeneous ductile materials and interfacial debonding in heterogeneous materials. Spall is simulated using continuum damage models and a level‐set–based crack generation and evolution algorithm. Three continuum damage models are tested for metal targets subjected to flyer impact; the results from the current code (SCIMITAR3D) are compared with the two widely used computer codes EPIC and CTH, and to experimental data; it is found that the computer codes are in good agreement among each other, but agreement of all methods with experimental data is not uniform. At material interfaces, damage is handled using a cohesive zone model and evolving level sets to create void spaces because of material separation due to debonding. Finally, ductile damage combined with debonding is simulated in an Al‐Ni laminate impacted by a projectile. The results demonstrate the ability of the present approach to simulate various types of damage in materials with heterogeneities and inclusions.  相似文献   
8.
Wireless Personal Communications - The communication among the vehicles in Vehicular Ad Hoc Network (VANET) plays a major role in the improvement of safety in critical situations of road scenario....  相似文献   
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10.
Abstract

Moving-boundary problems arise in numerous important physical phenomena, and often form complex shapes during their evolution. The ability to track the interface in such cases in two dimensions is well established. However, modifying the grid representing the interface as it evolves in three-dimensional space introduces additional issues. In the current work, three-dimensional interfaces are represented by adaptive unstructured grids. The grids are restructured and refined based on the shape and size of the triangular elements in the grid that forms the interfaces. As the interface deforms, points are automatically added to ensure that the accuracy of interface representation remains consistent. Results are presented to show how complex interface features, including surface curvatures and normals, can be captured by modifying an existing method that uses an approximation to the Dupin indicatrix.  相似文献   
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