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A realization of the Lie algebra associated to a Kantor triple system  [PDF]
Jakob Palmkvist
Mathematics , 2005, DOI: 10.1063/1.2168690
Abstract: We present a nonlinear realization of the 5-graded Lie algebra associated to a Kantor triple system. Any simple Lie algebra can be realized in this way, starting from an arbitrary 5-grading. In particular, we get a unified realization of the exceptional Lie algebras f_4, e_6, e_7, e_8, in which they are respectively related to the division algebras R, C, H, O.
Economic Feasibility of Hybrid Biomass/PV/ Wind System for Remote Villages Using HOMER  [PDF]
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering , 2013,
Abstract: The present paper discuss the economic feasibility of stand-alone hybrid power system consisting of Biomass/ PV/Wind generators for electrical requirements of the remote locations. It emphasizes the use of renewable hybrid power system to obtain a reliable autonomous system with the optimization of the components size and the improvement of thecapital cost. The main source of power to the energy system is biomass generator, whereas, photovoltaic panels and wind generators are the supported additional sources. The batteries are used to store extra energy generated that can further be used for the backup. This investigation assessed the potential of using solar, wind and biomass renewable energy in hybrid off-grid system. The optimization is realized through the NREL HOMER package.
Dynamic Analysis of Wind Generators  [PDF]
Ming-Hung Hsu
Journal of Applied Sciences , 2007,
Abstract: Wind power does not make any pollution and it also create a recyclable energy. The wind blade speeds significantly affect the measured output power. It is necessary to keep the wind blade tip speed to obtain maximum power. The wind blade speeds significantly affect the energy losses and the power coefficients. It is required to keep the wind blade tip speed to obtain the maximum power coefficient and minimum energy loss. The dynamic problems of the wind turbine generators are formulated by employing the differential quadrature method. The Euler-Bernoulli beam model is used to characterize the wind turbine generator blade. The differential quadrature method is used to transform the partial differential equations that present the dynamic behavior of the wind turbine generator blades into a discrete eigenvalue problem. The results show that the rotation speed could affect the frequencies of the wind generators. The inclined angle could not affect the frequencies of the wind generators significantly.
Organic Amendments with Chemical Fertilizers Improve Soil Fertility and Microbial Biomass in Rice-Rice-Rice Triple Crops Cropping Systems  [PDF]
Md. Farid Ahammed Anik, Md. Mizanur Rahman, G. K. M. Mustafizur Rahman, Md. Khairul Alam, Mahammad Shariful Islam, Mst Fatima Khatun
Open Journal of Soil Science (OJSS) , 2017, DOI: 10.4236/ojss.2017.75007
Abstract: Medium-term changes in the labile nutrient pool of microbial biomass carbon (MBC) and nitrogen (MBN) resulting from organic manure application in rice (Oryza sativa L.)-based triple cropping systems have been poorly studied. Therefore, the effects of organic materials on the soil physico-chemical properties and microbial biomass in rice fields were investigated at Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh, from April 2010 to December 2012. Five treatments (control, cow dung, poultry manure, rice straw, and chemical fertilizer) were laid out in a randomized complete block design with four replications. The organic residues (2 t C ha-1) were applied 7 days before transplanting and were combined with inorganic fertilizers, following integrated plant nutrition systems. This paper presents the results from the last of the five consecutive rice growing seasons. All of the organic residues increased the pH, and organic C, N, P, and K contents of the soil. However, poultry manure was more efficient in increasing soil fertility than cow dung and rice straw, resulting in a significant increase in P from 22 mg·kg-1 to 63 mg·kg-1 at crop harvest. All of the organic residues also increased the soil water holding capacity and decreased bulk density. Furthermore, poultry manure resulted in significantly higher microbial biomass C (432 mg·kg-1; P < 0.05) and N (31.60 mg·kg-1; P < 0.05) levels in the soil at crop harvest, followed by cow dung and rice straw. These findings indicate that the regular application of organic residues and manures will help to enhance soil fertility and production sustainability.
Operating of Small Wind Power Plants with Induction Generators  [cached]
Jakub Nevrala,Stanislav Misak
Advances in Electrical and Electronic Engineering , 2008,
Abstract: This paper describes different systems of small wind power plants with induction generators used in the Czech Republic. Problems of wind power plants running with induction generators are solved within partial target of the research project MSM 6198910007. For small wind power plants is used induction motor as a generator. Parameters of the name plate of motor must be resolved for generator running on measuring base. These generators are running as a separately working generators or generators connected to the power grid. Methods of control these systems as a separately working, directly connecting to power grid, control by frequency converter and wiring by synchronous cascade are confronted on the measuring base too.
Environmental Impact Assessment of Wind Generators in the Czech Republic  [PDF]
Vladimír Lap?ík
Acta Montanistica Slovaca , 2008,
Abstract: The article summarizes author′s experience with environmental impact assessment in branch of wind generators. The introductorypart of paper describes legislative obligations of the Czech Republic in frame of fulfilling the European Union′s limits in branch ofrenewable energy resources utilization. Next part of paper deals with analysis of impacts of wind generators on the environment.The final part of paper deals with experience with implementation of the environmental impact assessment process (pursuant to the ActNo. 100/2001 Coll.) in the field of wind power in the Czech Republic.
Ndinechi M. C.,Onwusuru I.M.,Ogungbenro O. A.
Academic Research International , 2012,
Abstract: The increased dependence on Hydrocarbon products as main source of energy in Nigeria has created a scenario of both human, technological and socio-economic lapses and setback in the country. Rampant use of diesel generators as means of alternative energy yields unrelenting greenhouse gas emission in the atmosphere thereby endangering human lives. However, efficient and renewable energy sources have been explored and have been adjudged to be viable, reliable and sustainablealternative. Unfortunately, some of the harnessed and most popular renewable energy sources like solar energy, geothermal, hydroelectricity, tidal power, wave and wind power are very expensive and consequently out of the reach of an average individual. Biomass energy is a cheap renewable energy that is locally sourced. Biogas is a type of biomass energy that can be produced from waste materials.This paper explored the use of animal dung as one of the sources of biogas as well as identifies its economic potential. Noting that small scale biogas production is fully capable of replacing rural energy requirement for lighting and cooking, harnessing it will alleviate the present energy problem. The large scale production is capable of generating and feeding electricity into the mainstream power grid. Since animal dung constitutes environmental pollution and yields pathogens and parasites that are harmful to health, it therefore becomes necessary to harness it for better use.
$γγ$ Event Generators  [PDF]
Leif Lonnblad,Mike Seymour,Edouard Boudinov,Jon Butterworth,Ralph Engel,Alex Finch,Suen Hou,Maria Kienzle-Focacci,Mark Lehto,Ed McKigney,David Miller,Denis Perret-Gallix,Johannes Ranft,Gerhard Schuler,Torbjorn Sjostrand,Rod Walker,Alison Wright
Physics , 1995,
Abstract: The report from the working group on '\gamma\gamma Event Generators' of the LEP 2 workshop
ЕКСПЕРИМЕНТАЛЬНЕ ДОСЛ ДЖЕННЯ КРИЛА З ГЕНЕРАТОРАМИ ВИХОР В Experimental investigation of wing with vortex generators Экспериментальное исследование крыла с генераторами вихрей  [cached]
?.П. Ударцев,О.Г. Щербонос
Proceedings of National Aviation University , 2010,
Abstract: Наведено результати випробувань в аеродинам чн й труб модел в дс ку крила з установленими генераторами вихор в у вигляд напливу на передню кромку. The idea of research of the organized vortex flow of a wing for the purpose of perfection of aerodynamic characteristics on the big angels of attack develops. The wing with vortex generators in the form of flows on a forward edge in low velocity wind tunnel was with that end in view investigated. It is shown, that the organized vortex flow of a wing with vortex generators on a forward edge practically does not change aerodynamic characteristics at small angels of attack and strongly influences on the big angels of attack, increasing the maximum elevating force and improving momentum characteristics at small change of drag. Для совершенствования аэродинамических характеристик на больших углах атаки выполняются исследования организованного вихревого обтекания крыла. С этой целью исследовали крыло конечного размаха с генераторами вихрей в виде наплывов на передней кромке в низкоскоростной аэродинамической трубе. Организованное вихревое обтекание крыла с генераторами вихрей на передней кромке практически не изменяет аэродинамических характеристик при малых углах атаки и влияет на больших углах атаки, увеличивая максимальную подъемную силу и улучшая моментные характеристики при малом изменении сопротивления.
The Comparative Analysis of Inductor and Reluctance Wind Generators
Edmunds Kamoli
Scientific Journal of Riga Technical University. Power and Electrical Engineering , 2009, DOI: 10.2478/v10144-009-0008-0
Abstract: In the presented work two designs of brushless generators are compared: inductor and reluctance. Both designs are multipolar and also can be applied as directly driven wind generators. Both one and the second designs are basically similar, but in the inductor generator are windings of excitation or permanent magnets which complicate a design, increase consumption of the copper and energy losses. In work shown that reluctance generator has no winding of excitation, it is simple and more reliable, it has less weight. It's more competitive for use in low power wind plants.
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