Mitigation of Lightning Hazards at the More Sensitive Points in Wind Farms Using Ant-Colony Optimization Technique

The lightning energy can be very harmfull to the wind turbine farm components. This paper attempts to evaluate the overvoltages at the sensitive points in wind farm, using ATP-EMTP package program. Four cases were performed; a) the transient voltage distribution in the insulating layer of the control line, b) the transient voltage on the control equipment, c) the coupling voltage between the tower and the control, and, d) the transient voltage distribution in the wind turbine WT generator, boast transformers and grid. These cases were performed under different lightning current conditions and at conventional design and proper design of grounding system. The results show that the ground potential rise (GPR) is reduced with using the proper design of wind turbine ground system, but the induced voltage at the control system will not affected. This work determines the optimum location of wind turbine at the areas of maximum lightning incidence. Ant colony optimization (ACO) technique is implemented to find the optimum wind farm location. This work enhances the protection strategy of the wind farms against lightning stroke

Correlation between Paris function parameters to crack velocity for Alumina ceramics

The question about the existence of correlation between the parameters A and m of the Paris function is re-examined theoretically for brittle material such as alumina ceramic (Al2O3) with different grain size. Investigation about existence of the exponential function which fit a good approximation to the majority of experimental data of crack velocity versus stress intensity factor diagram. The rate theory of crack growth was applied for data of alumina ceramics samples in region I and making use of the values of the exponential function parameters the crack growth rate theory parameters were estimated

Reactions with 5-Arylazo- and 5-Arylidene-4-thiohydantoin Derivatives

5-Arylazo-3-phenyl-4-thiohydantoins (IIa-g) have been prepared and then treated with primary aromatic amines to afford the corresponding 5-arylazo-4-arylimino-3-phenyl hydantoins (VIIa-c). 3-Phenyl-4-thiohydantoin reacted with aromatic aldehydes in the presence of glacial acetic acid and fused sodium acetate to give 5-arylidene-3-phenyl-4-thiohydantoin derivatives (VIIIa-e). In the coloured arylidene derivatives (VIII,a d, e) on treatment with alkyland/ or arylmagnesium halide addition occurs to the exocyclic double bond to give the products (IXa-e). The Grignard product (Xa) was oxidised with a mixture of chromic acid in glacial acetic acid to give phenyl parabanic acid and ethyl phenyl ketone

Fuzzy soft separation axioms in fuzzy soft topological spaces.

Fuzzy soft separation axioms was introduced by Mahanta and Das ([5]) using the definitions of a `fuzzy soft point' and `the complement of a fuzzy soft point is a fuzzy soft point', and `distinct of fuzzy soft points' in there sense.  In this paper we, introduce fuzzy soft separation axioms in terms of the modified definitions of a `fuzzy soft point', the complement of a fuzzy soft point is a fuzzy soft set' and `distinct of fuzzy soft points'([7]). Also, we study some of their properties. Finally, we discuss fuzzy soft topological property for such spaces.                                                          &nbsp

OPTIMAL DISTRIBUTED CONTROL OF STOCHASTIC ELLIPTIC SYSTEMS WITH CONSTRAINTS

The objective of this paper is to study the optimality for stochastic non cooperative elliptic systems. A distributed control problem for a stochastic elliptic systems with constraints on states and controls is studied. First, the existence and uniqueness of the state process for these systems are proved. The necessary and sufficient conditions of optimality are derived for the Dirichlet and Neumann problems

Design, Synthesis and Antibacterial Evaluation of some new 3,5-Diphenylcyclohex-2-en-1-one Derivatives

The moiety of cyclohexene has been showed highly antibacterial activity. New compounds were synthesized from diphenylcyclohexenone via reaction with a variety of reagents to afford branched chain of 1,3-diphenylcyclohexene or fused heterocyclic systems including pyrazole, chromen and pyrrole derivatives. Cyclic ketoketene s,s-acetal can be prepared by reaction with CS2/MeI under PTC conditions which in turn used as starting material for the synthesis of pyrazolyl and benzothiszolyl derivatives. Most of new synthesized compounds were characterized by using spectral data and were screened for their antibacterial activity

EFFECT OF VARIABLE WATER APPLICATION RATES ON YIELD OF FLAX AND IRRIGATION WATER USE EFFICIENCY

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Effects of zinc oxide nanoparticles (ZnO NPs) and some plant pathogens on the growth and nodulation of lentil (Lens culinaris Medik.)

Effects of ZnO nanoparticles (NPs) were studied on lentil plants inoculated with Alternaria alternata, Fusarium oxysporum f. sp. lentis, Xanthomonas axonopodis pv. phaseoli, Pseudomonas syringae pv. syringae and Meloidogyne incognita. Plant growth, chlorophyll, carotenoid contents, nitrate reductase (NR) activity and nodulation of lentil both in the presence and absence of Rhizobium sp. were examined in a pot test. Inoculation of plants with A. alternata / F. oxysporum f. sp. lentis / X. axonopodis pv. phaseoli / P. syringae pv. syringae or M. incognita caused a significant reduction in plant growth, number of pods per plant, chlorophyll, carotenoids and NR activity over uninoculated control. Inoculation of plants with Rhizobium sp. with or without pathogen increased plant growth and number of pods per plant, chlorophyll, carotenoids and NR activity. When plants were grown without Rhizobium, a foliar spray of plants with 10 ml solution of 0.1 mg ml–1of ZnO NPs per plant caused a significant increase in plant growth and number of pods, chlorophyll, carotenoid contents and NR activity in both inoculated and uninoculated plants. Spray of ZnO NPs to plants inoculated with Rhizobium sp. caused non significant increase in plant growth, number of pods per plant, chlorophyll, carotenoid contents and NR activity when plants were either uninoculated or inoculated with pathogens. Numbers of nodules per root system were high in plants treated with Rhizobium sp. but foliar spray of ZnO NPs had adverse effect on nodulation. Inoculation of plants with test pathogens also reduced nodulation. Spray of ZnO NPs to plants reduced galling, nematode multiplication, wilt, blight and leaf spot disease severity indices

Sensory and histological comparative investigation of frozen and salted-half dried fish

Fagyasztott állapotban - 5 C°-on tárolt és sózott-félig szárított állapotban tárolt halakon végeztek érzékszervi és szövettani vizsgálatokat. Megállapították, hogy a sózott-félig szárított halaknak rehidratizálásuk után kedvezőbb volt a színe, mint a fagyasztott halmintáké. Egyéb érzékszervi tulajdonságok tekintetében nem volt különbség észlelhető a kétféle módon tartósított halminták között. Sensorische und histologische Untersuchungen wurden mit in gefrorenem Zustand bei — 5°C gelagerten Fischen und in als gesalzte-halbgetrocknete Produkte gelagerten Fischen durchgeführt. Es wurde gefunden, dass die gesalztenhalbgetrockneten Fische nach ihrer Rehydratation eine günstigere Farbe besassen als die Farbe der gefrorenen Fische. Bei anderen sensorischen Eigenschaften wurden zwischen den durch die untersuchten beiden Konservierungsverfahren behandelten Fischprodukten keine Unterschiede beobachtet. Sensory and histological investigations were carried out with fish stored in a frozen state at - 5°C and with fish stored as salted-half dried product. 11 was found that salted-half dried fish showed, after its rehydration, a colour more favourable than the colour of the frozen fish samples. In other sensory properties no differences were perceptible between fish samples preserved by the examined two methods. On a effectué des examens sensoriques et histologiques sur des poissons entreposés en état congelé on mariné et mi-séché, ä — 5°C. On a établi qu’aprés réhydratation la couleur des poissons marinés et mi-séchés était meilleure que celle des poissons congelés. Quant au reste des carctéristiques sensoriques il n’y avait pás de différence entre les posissons conservés par les deux méthodes

Amelioration of The Dielectric Properties of Ceramic Insulators Using Nano-alumina

Outdoor HV porcelain insulators face various environmental stresses that cause their degradation. Consequently, amelioration of their insulating properties becomes a target of recent researches to survive higher voltage levels. Investigating the impact of the addition of 0, 5, 10, and 15 wt. % nano- alumina (NA) on the dielectric and physical characteristics of porcelain materials at elevated sintering temperatures is the aim of this study. Porcelain specimens were synthesized from kaolin, feldspar, and quartz as available low-cost raw materials. The specimens were sintered at 1100, 1200, 1300, and 1400°C for 2 h. For some specimens, the microstructure and phases formed were identified using scanning electron microscopy and X-ray diffraction techniques. The changes that occur upon heating (include melting, phase transition, sublimation, and decomposition) were identified by Differential Thermogravimetric Analysis. The dielectric strength, relative permittivity, and loss tangent of different samples were measured at a large scale of frequencies. Breakdown strength values of different samples were verified by applying the Finite Element Method. The best electrical and physical properties were achieved at 1300ºC. At this temperature the porcelain sample containing 5 wt. % NA presented optimum physical characteristics as well as good insulating properties assent the feasibility of producing electro-technical porcelai