Academic literature on the topic 'Računarska simulacija'

Tema rada je istraživanje primena ćelijskih automata u procesu analize i projektovanja mikro-urbanih celina. Rad istražuje savremene računar­ske tehnologije i njihovu primenu u arhitekturi i urbanizmu kao i ugledne primere revitalizacije malih urbanih prostora. Osmišljen algoritam omogućava kompjutersku simulaciju potencijalnog razvoja malih urbanih celina ubrzavajući proces projektovanja istih.

This paper present a novel methodological approach in the design of integrated tactical telecommunications and computer networks for command information system and defining the elements for the OPNET simulation model. The elements proposed for design of network information architecture. For that purpose, the way established to set up relationships between elements that uses for network topologies design, building of network elements and network traffic. They are integrated with its parameters in the preliminary model defined by an OPNET simulation model. We propose the measure of efficiency for accomplishment of tactical command requirements to use the design model network. This measure of efficiency is mean time delay that described with mathematical relations, involving the communication parameters speed of generating traffic, packet size, link capacity and adequately reflects the projected network. Furthermore, the applications of the proposed approach and given instructions allow to designers full examination of the network architecture, and provide translation into preliminary model and design OPNET simulation model.

U mnogim granama tehnike javljaju se problemimerenja protoka fluida. Merne blende, zbog svojihmnogih prednosti predstavljaju najzastupljenijiinstrument za merenje protoka fluida kroz cevovode. Sadruge strane njihova upotreba povećava tro&scaron;kove radaindustrijskih postrojenja. Jedan od ciljeva ovedoktorske disertacije bio je ispitivanje novih oblikamernih blendi u cilju u&scaron;tede energije pri njihovom radu.U ovoj doktorskoj disertaciji predložen je algoritamispitivanja novih oblika mernih blendi. Takođe jekonstruisana i izrađena laboratorijska aparatura zanjihovo ispitivanje kao i diferncijalni &quot;U&quot; manometarza merenje malih razlika pritisaka. U okviru ovedoktorske disertacije dizajnirana su i ispitana tri novaoblika mernih blendi. U&scaron;teda energije je postignutadizajnom koji smanjuje otpor merne blende kaoelementa cevovoda. Novi oblici mernih blendi, kao ijedna standardnog oblika koja je poslužila kaoreferentna, ispitani su prema predloženom algoritmu. Uprvom koraku merne blende su dizajnirane uprogramskom paketu Solid Works. Zatim su, premapredloženom algoritmu, ispitane pomoću računarske simulacije u programskom paketu COMSOL Multiphysics. Po dobijanju zadovoljavajućih rezultata računarske simulacije, merne blende su izrađene na 3D &scaron;tampaču, FDM postupkom i ispitane na laboratorijskoj aparaturi. Rezultati laboratorijskih ispitivanja su upoređeni sa rezultatima računarske simulacije. Upoređeni rezultati računarske simulacije i laboratorijskih ispitivanja su pokazali da je računarska simulacija dobro opisivala situaciju. Rezultati laboratorijskog ispitivanja su pokazali znatan efekat u&scaron;tede energije. Takođe je utvrđeno da se pomoću računarske simulacije mogu dobiti podaci na osnovu kojih se može doneti odluka da li novi oblik merne blende treba korigovati ili ima smisla pristupiti laboratorijskom ispitivanju. Algoritam ispitivanja koji je predložen u ovoj doktorskoj disertaciji se pokazao efikasnim.&nbsp;<br>In many domains of technology, there are problemswith the measurement of fluid flow. Orifice plates,because of their many advantages, represent the mostcommon instrument for measuring fluid flow throughpipelines. On the other hand, their use increases theoperating cost of industrial plants. One of the goals ofthis doctoral dissertation was to test new forms oforifice plates for a reason to save energy during theirwork. An algorithm for testing new forms of orificeplates is proposed. Also, the laboratory equipment fortesting them was designed and made, as well as adifferential &quot;U&quot; manometer for measuring smallpressure differences. As part of this doctoraldissertation are designed and tested three new forms oforifice plates. Energy-saving was achieved by a designthat reduces the resistance of the orifice plate as anelement of the pipeline. New forms of orifice plates, as well as a standard shape, which served as a reference, were tested according to the present algorithm. In the first step, orifice plates are designed in the Solid Works software package. Then, according to the proposed algorithm, they were tested using computer simulation in COMSOL Multiphysics software package. After achieving satisfactory results of computer simulation, orifice plates are made on a 3D printer, using the FDM process and tested in the laboratory apparatus. The results of laboratory tests were compared with the results of computer simulations. Compared results of computer simulation and laboratory testing showed that computer simulation described the situation well. The results of the laboratory test showed a significant energy-saving effect. It was also found that computer simulation can obtain data that can decide whether a new form of orifice plate must be corrected or it makes sense to access laboratory testing. The algorithm proposed in this doctoral dissertation has proven effective.

U&nbsp; ovoj&nbsp; doktorskoj&nbsp; disertaciji&nbsp; sintetisane&nbsp; su&nbsp; dve&nbsp; različite&nbsp; klase jonskih&nbsp; tečnosti,&nbsp; na&nbsp; bazi&nbsp; imidazolijuma&nbsp; i&nbsp; holinijuma,&nbsp; sa&nbsp; ciljem snižavanja&nbsp; toksičnosti.&nbsp; Imidazolijumove&nbsp; jonske&nbsp; tečnosti&nbsp; su funkcionalizovane&nbsp; hidroksilnom&nbsp; i&nbsp; etarskom&nbsp; grupom&nbsp; u&nbsp; bočnom lancu. Uspe&scaron;nost sinteza jonskih tečnosti potvrđena je&nbsp; snimanjem IC&nbsp; i&nbsp; NMR&nbsp; spektara.&nbsp; Izmerene&nbsp; su&nbsp; gustine,&nbsp; viskoznosti&nbsp; i provodljivosti&nbsp; čistih&nbsp; imidazolijumovih&nbsp; i&nbsp; holinijumskih&nbsp; jonskih tečnosti.&nbsp; Na&nbsp; osnovu&nbsp; dobijenih&nbsp; eksperimentalnih&nbsp; rezultata,potpomognutim&nbsp; računarskim&nbsp; simulacijama&nbsp; diskutovana&nbsp; je strukturna organizacija između katjona i anjona. Utvrđeno je da prisustvo&nbsp; hidroksilne&nbsp; grupe&nbsp; u&nbsp; bočnom&nbsp; lancu&nbsp; imidazolovog katjona,&nbsp; značajno&nbsp; utiče&nbsp; na&nbsp; lokaciju&nbsp; anjona&nbsp; i&nbsp; samim&nbsp; tim&nbsp; na makroskopska&nbsp; svojstva.&nbsp; U&nbsp; nastavku&nbsp; su&nbsp; izmerene&nbsp; gustine&nbsp; i viskoznosti&nbsp; vodenih&nbsp; rastvora&nbsp; sa&nbsp; ciljem&nbsp; dobijanja&nbsp; informacija&nbsp; o uticaju&nbsp; dodatka&nbsp; holinijumskih&nbsp; i&nbsp; imidazolijumovih&nbsp; jonskih tečnosti&nbsp; na&nbsp; strukturu&nbsp; vode.&nbsp; Na&nbsp; osnovu&nbsp; B&nbsp; koeficijenta&nbsp; izviskoznosti,&nbsp; ekspanzibilnosti&nbsp; i&nbsp; rezultata&nbsp; simulacija&nbsp; molekulske dinamike,&nbsp; utvrđeno&nbsp; je&nbsp; da&nbsp; sve&nbsp; jonske&nbsp; tečnosti&nbsp; imaju&nbsp; structure making&nbsp; osobine.&nbsp; Takođe,&nbsp; na&nbsp; osnovu&nbsp; izračunatih&nbsp; specifičnih molarnih zapremina i doking analize na receptoru za gorak ukus,ustanovljeno je da vodeni rastvori holinijumskih jonskih tečnosti imaju gorak ukus.Toksičnost funkcionalizovanih imidazolijumovih jonskih tečnosti ispitana je na&nbsp; nekoliko biljnih vrsta&nbsp; (p&scaron;enica, ječam i krastavac), kao i na larvama&nbsp; <em>A.&nbsp; salina</em>&nbsp; i ćelijskoj liniji MRC-5. Potvrđeno jeda&nbsp; uvođenje&nbsp; hidroksilne&nbsp; grupe&nbsp; u&nbsp; alkil&nbsp; niz&nbsp; najvi&scaron;e&nbsp; se&nbsp; redukujutoksičnosti&nbsp; imidazolijumovih&nbsp; jonskih&nbsp; tečnosti,&nbsp; dok&nbsp; je&nbsp; uticaj etarske&nbsp; grupe&nbsp; na&nbsp; smanjenje&nbsp; toksičnosti&nbsp; značajno&nbsp; manji. Ispitivanje&nbsp; citotoksičnosti&nbsp; i&nbsp; antibakterijske&nbsp; aktivnosti&nbsp; ukazalo&nbsp; je da holinijumske jonske tečnosti se mogu smatrati netoksičnima, ipokazuju&nbsp; beningnije&nbsp; dejstvo&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; njihovim&nbsp; polaznim komponentama&nbsp; (askorbinska&nbsp; kiselina,&nbsp; biotin&nbsp; i&nbsp; nikotinska kiselina).<br>In&nbsp; this&nbsp; doctoral&nbsp; thesis,&nbsp; ionic&nbsp; liquids&nbsp; based&nbsp; on&nbsp; imidazolium&nbsp; and cholinium cation were synthesized, in order to obtain new class of ILs with reduced toxicity. Imidazolium based ionic liquids were functionalized&nbsp; with hydroxyl and ether&nbsp; group in &nbsp; order to reduce their&nbsp; lipophilicity.&nbsp; All&nbsp; newly&nbsp; synthesized&nbsp; compounds&nbsp; were&nbsp; confirmed&nbsp; by&nbsp; measuring&nbsp; IR&nbsp; and&nbsp; NMR&nbsp; spectra.&nbsp; For&nbsp; pure&nbsp; ionic&nbsp; liquids, density, conductivity and viscosity were measured. Based on&nbsp; the&nbsp; obtained&nbsp; experimental&nbsp; results&nbsp; supported&nbsp; with&nbsp; results&nbsp; of&nbsp; molecular simulations, it was concluded that presence of oxygen in&nbsp; alkyl&nbsp; side&nbsp; chain&nbsp; of&nbsp; imidazolium&nbsp; ionic&nbsp; liquids&nbsp; significantly contribute to position of anion. Further,&nbsp; density&nbsp; and&nbsp; viscosity&nbsp; of&nbsp; diluted&nbsp; aqueous&nbsp; ILs&nbsp; solutions were&nbsp; measured&nbsp; with&nbsp; a&nbsp; purpose&nbsp; to&nbsp; investigate&nbsp; their&nbsp; influence&nbsp; on water&nbsp; structure.&nbsp; Based&nbsp; on&nbsp; obtained&nbsp; values&nbsp; for&nbsp; viscosicty&nbsp; B coefficient,&nbsp; expansibility&nbsp; and&nbsp; from&nbsp; MD&nbsp; simulations,&nbsp; all&nbsp; ionic&nbsp; liquids&nbsp; express&nbsp; structure&nbsp; making&nbsp; tendency.&nbsp; From&nbsp; calculated specific&nbsp; apparent&nbsp; molar&nbsp; volumes&nbsp; for&nbsp; cholinium&nbsp; ionic&nbsp; liquids&nbsp; it was noted bitter taste.&nbsp; The&nbsp; toxicity&nbsp; of&nbsp; functionalized&nbsp; imidazolium&nbsp; ionic&nbsp; liquids&nbsp; was investigated&nbsp; on&nbsp; different&nbsp; plant&nbsp; species&nbsp; (wheat ,&nbsp; barley&nbsp; and cucumber),&nbsp; on&nbsp; larvae&nbsp; of&nbsp;<em> A.&nbsp; salina</em>&nbsp; and&nbsp; cell&nbsp; line&nbsp; MRC-5.&nbsp; Fromobtained&nbsp; results&nbsp; it&nbsp; was&nbsp; concluded&nbsp; that&nbsp; introduction&nbsp; of&nbsp; hydroxyl group in alkyl side chain reduce toxicity significantly more than&nbsp; ether&nbsp; group.&nbsp; Experiments&nbsp; on&nbsp; cytotoxicicity&nbsp; and&nbsp; antibacterial effects&nbsp; allowed&nbsp; to&nbsp; conclude&nbsp; that&nbsp; those&nbsp; newly&nbsp; synthesized cholinium ionic liquids can be considered as non-toxic.