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151.
In this theoretical investigation, a hybrid power generation system utilizing wind energy and hydrogen storage is presented. Firstly, the available wind energy is determined, which is followed by evaluating the efficiency of the wind energy conversion system. A revised model of windmill is proposed from which wind power density and electric power output are determined. When the load demand is less than the output of the generation, the excess electric power is relayed to the electrolytic cell where it is used to electrolyze the de‐ionized water. Hydrogen thus produced can be stored as hydrogen compressed gas or liquid. Once the hydrogen is stored in an appropriate high‐pressure vessel, it can be used in a combustion engine, fuel cell, or burned in a water‐cooled burner to produce a very high‐quality steam for space heating, or to drive a turbine to generate electric power. It can also be combined with organic materials to produce synthetic fuels. The conclusion is that the system produces no harmful waste and depletes no resources. Note that this system also works well with a solar collector instead of a windmill. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Water Resources Management - Slit-check dams have a flow regulation function under normal flow conditions as well as holding large solid (debris flow control). However, the effects of such... 相似文献
155.
Nikbakhsh Javadian Aydin Aghajani Javad Rezaeian Mohammad Javad Ghaneian Sebdani 《The International Journal of Advanced Manufacturing Technology》2011,56(1-4):307-317
Cellular manufacturing system (CMS)—an important application of group technology—has been recognized as an effective way to enhance the productivity in a factory. As a result of dynamic deterministic demands within the planning horizon, a CMS configuration for a period might not be optimal or even feasible for other planning periods. Consequently, a multi-objective dynamic cell formation problem is presented, where the total cells load variation and sum of the miscellaneous costs are to be minimized simultaneously. The second objective function calculates machine costs, internal part production, intercellular and intracellular material handling, back order, inventory holding and subcontracting. Since in this type of problem, objectives are in conflict with each other, finding an ideal solution (a solution which satisfies all objectives simultaneously) is not possible. Therefore a non-dominated sorting genetic algorithm (NSGAII) is designed for finding Pareto-optimal frontier that decision maker can select her/his slightly solution. Numerical examples have been solved for demonstrate the efficiency of the proposed algorithm. 相似文献
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Estimating uniaxial compressive strength of rocks using genetic expression programming 总被引:3,自引:0,他引:3
The aim of this paper is to estimate the uniaxial compressive strength(UCS) of rocks with different characteristics by using genetic expression programming(GEP).For this purpose,five different types of rocks including basalt and ignimbrite(black,yellow,gray,brown) were prepared.Values of unit weight,water absorption by weight,effective porosity and UCS of rocks were determined experimentally.By using these experimental data,five different GEP models were developed for estimating the values of UCS for different rock types.Good agreement between experimental data and predicted results is obtained. 相似文献
158.
This study concentrates on user assisted disparity remapping for stereo image footage, i.e. the disparity of an object of interest is altered while leaving the remaining scene unattended. This application is useful in the sense that it provides a method for emphasizing/de-emphasizing an object on the scene by adjusting its depth with respect to the camera. The proposed technique can also be used as a post-processing step for retargeting stereoscopic footage on different display sizes and resolutions. The proposed technique involves an MRF-based energy minimization step for interactive stereo image segmentation, for which user assistance on only one of the stereo pairs is required for determining the location of stereo object pair. A key contribution of the proposed study is elimination of dense disparity estimation step from the pipeline. This step is realized through a sparse feature matching technique between the stereo pairs. Moreover, by the help of the proposed technique, novel disparity adjusted views are synthesized using the produced stereo object segments and background information for the images. Qualitative and quantitative evaluation of the generated segments and the disparity adjusted images prove the functionality and superiority of the proposed technique. 相似文献
159.
AbstractThe oxygen tracer diffusion coefficient describing transport along nano-/microscaled YSZ/Sc2O3 multilayers as a function of the thickness of the ion-conducting YSZ layers has been measured by isotope exchange depth profiling (IEDP), using secondary ion mass spectrometry (SIMS). The multilayer samples were prepared by pulsed laser deposition (PLD) on (0001) Al2O3 single crystalline substrates. The values for the oxygen tracer diffusion coefficient were analyzed as a combination of contributions from bulk and interface contributions and compared with results from YSZ/Y2O3-multilayers with similar microstructure. Using the Nernst–Einstein equation as the relation between diffusivity and electrical conductivity we find very good agreement between conductivity and diffusion data, and we exclude substantial electronic conductivity in the multilayers. The effect of hetero-interface transport can be well explained by a simple interface strain model. As the multilayer samples consist of columnar film crystallites with a defined interface structure and texture, we also discuss the influence of this particular microstructure on the interfacial strain. 相似文献
160.
Recep Kotan Dr Ahmet Cakir Fatih Dadasoglu Tuba Aydin Ramazan Cakmakci Hakan Ozer Saban Kordali Ebru Mete Neslihan Dikbas 《Journal of the science of food and agriculture》2010,90(1):145-160
BACKGROUND: The aims of this study were to examine the chemical composition of the essential oils and hexane extracts of the aerial parts of Satureja spicigera (C. Koch) Boiss., Thymus fallax Fisch. & CA Mey, Achillea biebersteinii Afan, and Achillea millefolium L. by GC and GC–MS, and to test antibacterial efficacy of essential oils and n‐hexane, chloroform, acetone and methanol extracts as an antibacterial and seed disinfectant against 25 agricultural plant pathogens. RESULTS: Thymol, carvacrol, p‐cymene, thymol methyl ether and γ‐terpinene were the main constituents of S. spicigera and T. fallax oils and hexane extracts. The main components of the oil of Achillea millefolium were 1,8‐cineole, δ‐cadinol and caryophyllene oxide, whereas the hexane extract of this species contained mainly n‐hexacosane, n‐tricosane and n‐heneicosane. The oils and hexane extracts of S. spicigera and T. fallax exhibited potent antibacterial activity over a broad spectrum against 25 phytopathogenic bacterial strains. Carvacrol and thymol, the major constituents of S. spicigera and T. fallax oils, also showed potent antibacterial effect against the bacteria tested. The oils of Achillea species showed weak antibacterial activity. Our results also revealed that the essential oil of S. spicigera, thymol and carvacrol could be used as potential disinfection agents against seed‐borne bacteria. CONCLUSION: Our results demonstrate that S. spicigera, T. fallax oils, carvacrol and thymol could become potentials for controlling certain important agricultural plant pathogenic bacteria and seed disinfectant. Copyright © 2009 Society of Chemical Industry 相似文献