992 resultados para Conduction Problem


Relevância:

20.00% 20.00%

Publicador:

Resumo:

importance of fishing and other allied industries in the economy was realised only very recently. Consequently only very few studies are available on the subject. Here an attempt is made to survey the available literature on the subject.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The set of vertices that maximize (minimize) the remoteness is the antimedian (median) set of the profile. It is proved that for an arbitrary graph G and S V (G) it can be decided in polynomial time whether S is the antimedian set of some profile. Graphs in which every antimedian set is connected are also considered.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nanoparticles of manganese ferrite were prepared by the chemical co-precipitation technique. The dielectric parameters, namely, real and imaginary dielectric permittivity (ε and ε ), ac conductivity (σac) and dielectric loss tangent (tan δ), were measured in the frequency range of 100 kHz–8MHz at different temperatures. The variations of dielectric dispersion (ε ) and dielectric absorption (ε ) with frequency and temperature were also investigated. The variation of dielectric permittivity with frequency and temperature followed the Maxwell–Wagner model based on interfacial polarization in consonance with Koops phenomenological theory. The dielectric loss tangent and hence ε exhibited a relaxation at certain frequencies and at relatively higher temperatures. The dispersion of dielectric permittivity and broadening of the dielectric absorption suggest the possibility of a distribution of relaxation time and the existence of multiple equilibrium states in manganese ferrite. The activation energy estimated from the dielectric relaxation is found to be high and is characteristic of polaron conduction in the nanosized manganese ferrite. The ac conductivity followed a power law dependence σac = Bωn typical of charge transport assisted by a hopping or tunnelling process. The observed minimum in the temperature dependence of the frequency exponent n strongly suggests that tunnelling of the large polarons is the dominant transport process

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Electrical properties of ac plasma polymerized aniline thin films are investigated with a view of determining the dominant conduction mechanism. The current–voltage (I–V) characteristics in symmetric and asymmetric electrode configuration for polyaniline thin films in the thickness range from 1300 to 2000 A ° are investigated. From the studies on asymmetric electrode configuration, it is found that the dominant conduction mechanism in these films is of Schottky type

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mn1−xZnxFe2O4 nanoparticles (x = 0 to 1) were synthesized by the wet chemical co-precipitation technique. X-ray diffraction and transmission electron microscopy and high resolution transmission electron microscopy were effectively utilized to investigate the different structural parameters. The ac conductivity of nanosized Mn1−xZnxFe2O4 were investigated as a function of frequency, temperature and composition. The frequency dependence of ac conductivity is analysed by the power law σ(ω)ac = Bωn which is typical for charge transport by hopping or tunnelling processes. The temperature dependence of frequency exponent n was investigated to understand the conduction mechanism in different compositions. The conduction mechanisms are mainly based on polaron hopping conduction

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Materials belonging to the family of manganites are technologically important since they exhibit colossal magneto resistance. A proper understanding of the transport properties is very vital in tailoring the properties. A heavy rare earth doped manganite like Gd0·7Sr0·3MnO3 is purported to be exhibiting unusual properties because of smaller ionic radius of Gd. Gd0·7Sr0·3MnO3 is prepared by a wet solid state reaction method. The conduction mechanism in such a compound has been elucidated by subjecting the material to low temperature d.c. conductivity measurement. It has been found that the low band width material follows a variable range hopping (VRH) model followed by a small polaron hopping (SPH) model. The results are presented here

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents Reinforcement Learning (RL) approaches to Economic Dispatch problem. In this paper, formulation of Economic Dispatch as a multi stage decision making problem is carried out, then two variants of RL algorithms are presented. A third algorithm which takes into consideration the transmission losses is also explained. Efficiency and flexibility of the proposed algorithms are demonstrated through different representative systems: a three generator system with given generation cost table, IEEE 30 bus system with quadratic cost functions, 10 generator system having piecewise quadratic cost functions and a 20 generator system considering transmission losses. A comparison of the computation times of different algorithms is also carried out.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Unit Commitment Problem (UCP) in power system refers to the problem of determining the on/ off status of generating units that minimize the operating cost during a given time horizon. Since various system and generation constraints are to be satisfied while finding the optimum schedule, UCP turns to be a constrained optimization problem in power system scheduling. Numerical solutions developed are limited for small systems and heuristic methodologies find difficulty in handling stochastic cost functions associated with practical systems. This paper models Unit Commitment as a multi stage decision making task and an efficient Reinforcement Learning solution is formulated considering minimum up time /down time constraints. The correctness and efficiency of the developed solutions are verified for standard test systems

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Unit commitment is an optimization task in electric power generation control sector. It involves scheduling the ON/OFF status of the generating units to meet the load demand with minimum generation cost satisfying the different constraints existing in the system. Numerical solutions developed are limited for small systems and heuristic methodologies find difficulty in handling stochastic cost functions associated with practical systems. This paper models Unit Commitment as a multi stage decision task and Reinforcement Learning solution is formulated through one efficient exploration strategy: Pursuit method. The correctness and efficiency of the developed solutions are verified for standard test systems

Relevância:

20.00% 20.00%

Publicador:

Resumo:

One comes across directions as the observations in a number of situations. The first inferential question that one should answer when dealing with such data is, “Are they isotropic or uniformly distributed?” The answer to this question goes back in history which we shall retrace a bit and provide an exact and approximate solution to this so-called “Pearson’s Random Walk” problem.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The The The The growing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demandgrowing demand for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of for the expansion of the the the the publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system publicly funded system of education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goodof education as merit and free goods emphasized emphasized emphasized emphasized emphasized emphasized emphasized emphasized emphasized emphasized on large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation large allocation of funds on of funds on of funds on of funds on of funds on of funds on of funds on of funds on of funds on of funds on of funds for promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting educationfor promoting education. Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to . Compared to the rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of Indiathe rest of India, Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead , Kerala is far ahead in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect in this respect primarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the eprimarily because of the earlierarlierarlierarlierarlierarlier political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social political and social compulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions ofcompulsions of the state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The prethe state. The presumption of sumption of sumption of sumption of sumption of sumption of sumption of sumption of sumption of sumption of sumption of assured assured assured assured assured assured assured assured and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed and guaranteed employment in employment in employment in employment in employment in employment in employment in employment in employment in employment in employment in employment in the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East the Middle East and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other and also in other countries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased furthecountries increased further the scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher educationthe scope of higher education in KeralaKeralaKeralaKeralaKeralaKerala, particularparticularparticularparticularparticularparticularparticularparticularparticularparticularly the technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe technical educationthe

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Thermoaktive Bauteilsysteme sind Bauteile, die als Teil der Raumumschließungsflächen über ein integriertes Rohrsystem mit einem Heiz- oder Kühlmedium beaufschlagt werden können und so die Beheizung oder Kühlung des Raumes ermöglichen. Die Konstruktionenvielfalt reicht nach diesem Verständnis von Heiz, bzw. Kühldecken über Geschoßtrenndecken mit kern-integrierten Rohren bis hin zu den Fußbodenheizungen. Die darin enthaltenen extrem trägen Systeme werden bewußt eingesetzt, um Energieangebot und Raumenergiebedarf unter dem Aspekt der rationellen Energieanwendung zeitlich zu entkoppeln, z. B. aktive Bauteilkühlung in der Nacht, passive Raumkühlung über das kühle Bauteil am Tage. Gebäude- und Anlagenkonzepte, die träge reagierende thermoaktive Bauteilsysteme vorsehen, setzen im kompetenten und verantwortungsvollen Planungsprozeß den Einsatz moderner Gebäudesimulationswerkzeuge voraus, um fundierte Aussagen über Behaglichkeit und Energiebedarf treffen zu können. Die thermoaktiven Bauteilsysteme werden innerhalb dieser Werkzeuge durch Berechnungskomponenten repräsentiert, die auf mathematisch-physikalischen Modellen basieren und zur Lösung des bauteilimmanenten mehrdimensionalen instationären Wärmeleitungsproblems dienen. Bisher standen hierfür zwei unterschiedliche prinzipielle Vorgehensweisen zur Lösung zur Verfügung, die der physikalischen Modellbildung entstammen und Grenzen bzgl. abbildbarer Geometrie oder Rechengeschwindigkeit setzen. Die vorliegende Arbeit dokumentiert eine neue Herangehensweise, die als experimentelle Modellbildung bezeichnet wird. Über den Weg der Systemidentifikation können aus experimentell ermittelten Datenreihen die Parameter für ein kompaktes Black-Box-Modell bestimmt werden, das das Eingangs-Ausgangsverhalten des zugehörigen beliebig aufgebauten thermoaktiven Bauteils mit hinreichender Genauigkeit widergibt. Die Meßdatenreihen lassen sich über hochgenaue Berechnungen generieren, die auf Grund ihrer Detailtreue für den unmittelbaren Einsatz in der Gebäudesimulation ungeeignet wären. Die Anwendung der Systemidentifikation auf das zweidimensionale Wärmeleitungsproblem und der Nachweis ihrer Eignung wird an Hand von sechs sehr unterschiedlichen Aufbauten thermoaktiver Bauteilsysteme durchgeführt und bestätigt sehr geringe Temperatur- und Energiebilanzfehler. Vergleiche zwischen via Systemidentifikation ermittelten Black-Box-Modellen und physikalischen Modellen für zwei Fußbodenkonstruktionen zeigen, daß erstgenannte auch als Referenz für Genauigkeitsabschätzungen herangezogen werden können. Die Praktikabilität des neuen Modellierungsansatzes wird an Fallstudien demonstriert, die Ganzjahressimulationen unter Bauteil- und Betriebsvariationen an einem exemplarischen Büroraum betreffen. Dazu erfolgt die Integration des Black-Box-Modells in das kommerzielle Gebäude- und Anlagensimulationsprogramm CARNOT. Die akzeptablen Rechenzeiten für ein Einzonen-Gebäudemodell in Verbindung mit den hohen Genauigkeiten bescheinigen die Eignung der neuen Modellierungsweise.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper re-addresses the issue of a lacking genuine design research paradigm. It tries to sketch an operational model of such a paradigm, based upon a generic design process model, which is derived from basic notions of evolution and learning in different domains of knowing (and turns out to be not very different from existing ones). It does not abandon the scientific paradigm but concludes that the latter has to be embedded into / subordinated under a design paradigm.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Quasi-molecular X-rays observed in heavy ion collisions are interpreted within a relativistic calculation of correlation diagrams using the Dirac-Slater model. A semiquantitative description of noncharacteristic M X rays is given for the system Au-I.