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1

Åsberg, Philip, and Pontus Bohlins. "Tidig detektering av skogsbränder med hjälp av högupplöst data : Automatisk identifiering med hjälp av bildbehandling." Thesis, Högskolan i Gävle, Datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-29786.

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Skogsbränder är svåra att upptäcka i ett tidigt stadie, vilket leder till förödande konsekvenser. Hela 30 % av koldioxiden som atmosfären tar emot kommer från skogsbränder. Flera tusentals människor och djur mister livet eller tvingas lämna sina hem. Det finns idag flera tekniker som med varierande framgång kan upptäcka skogsbränder. I detta arbete skall en alternativ metod för rökdetektering utvecklas och testas. Metoden ska vara möjlig att appliceras på UAV (Unmanned Aerial Vehicle) teknik. Arbetet fokuserar på att skilja på brandrök och dimma med högupplöst data. Två algoritmer prövas, SDA (Statistisk distributions algoritm) och KBA (Kunskapsbaserad igenkännings algoritm). Den första testar statistiska distributioner för att hitta unika identifierare för rök. Den andra algoritmen är baserad på kunskapen om rök vad gäller spektrala och morfologiska egenskaper. Röken identifieras med hjälp av form, area och kanter. Algoritmen visade en precision med 90 % i bilder innehållande rök och en feldetektering med 20 % för bilder innehållande dimma.
It is very difficult to discover forest fires in an early stage which can lead to devastat-ing consequences. Today, 30% of the total carbon dioxide that is released in the at-mosphere comes from forest fires. Thousands of human beings and animals are killed or forced to leave their homes every year. There are a variety of techniques today that is being used for discovering forest fires but whom lack in accuracy or has problems with a large amount of false alarms. This paper is an experimental study to try to solve this issue. The proposed method in this paper could be applied on UAV (Unmanned Arial Vehicles). This study will focus on identifying smoke regions from forest fires and removing fog objects which has similar characteristics as smoke. Two algorithms are tested, SDA (Statistical distributions algorithm) and KBA (Knowledge-based identification algorithm). The SDA uses statistic distribution al-gorithm where smoke and fogs characteristics are identified. The second algorithm, KBA, is a knowledge-based algorithm, where the shape, area and edges of the smoke’s characteristics are applied. The algorithm showed a 90 % accuracy for find-ing smoke in images with a false alarm rate of 20 % in images of fog.
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2

Garibaldi, Castillo Oscar Daniel. "Determination of the spatial distribution of atmospheric fluxes by using a UAV." Thesis, Purdue University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10152666.

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It is well known that the composition of the planet's atmosphere is changing at an unprecedented rate. Tremendous and well-documented amounts of man-made carbon are being released into the atmosphere, but is not clear where that extra carbon is going and how it interacts with the environment. The influence of human activities on the carbon cycle is of particular concern to scientists and policymakers. To clarify this important issue, in-situ measurements must be taken to improve our understanding of the mechanism that drives the exchange of CO2 within the atmosphere, which is dominated by turbulence. As such, there is great interest in the measurement of CO2 concentration and CO2 flux within the atmosphere.

A wide variety of platforms, in both mobile and fixed configurations, are being used to study closely the flux of CO2 within the atmosphere's boundary layer. Most of these platforms tend to be expensive and complex to operate. Recent developments of technologies such as microelectromechanical devices, GPS, and batteries have enabled the use of unmanned aerial vehicles as a viable method for performing atmospheric studies. Parallel to the studies of carbon exchange, field measurements of buoyancy flux are valuable. This variable helps to understand the mechanisms of turbulence production. It can be assessed with the use of a sonic anemometer, which has the ability of measuring wind speed fluctuations, alongside with virtual temperature. This has motivated the creation of an instrumented UAV the measurement of in situ variables such as CO2 flux, virtual temperature, wind speed, and turbulence.

An unmanned aerial system, nicknamed UAV Esperanza, was designed, constructed and tested with the purpose of measuring turbulent flux. The novelty of this system was the incorporation of an onboard sonic anemometer, an inexpensive inertial measurement unit/GPS navigation system, and a relatively low-cost gas analyzer. Field experiments demonstrated the capability of the system to resolve vertical profiles of average wind speed, virtual potential temperature, turbulent kinetic energy, CO2 concentration, and turbulent fluxes of buoyancy and CO2. The UAV system has the ability to obtain average CO2 flux values comparable to existing manned aircraft-based systems. Moreover, this is accomplished with a fraction of the operational costs of manned airplanes.

Error analysis of different scenarios demonstrated that the developed UAV system is appropriate for measuring plumes of power plants, daytime fluxes of crops, and forests. However, limitations of the onboard gas analyzer, range, and endurance of the aircraft render the system unsuitable for spectrum analysis

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3

Holden, Erin. "Spatial Ecology and Remote Sensing in the Precision Management of Tetranychus urticae (Acari: Tetranychidae)in Peanut." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/36225.

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The twospotted spider mite (TSSM), Tetranychus urticae Koch, is a common polyphagous pest in peanut agroecosystems. The mite has caused serious economic losses to peanut farmers in the Virginia-Carolina area, where approximately 20% of the peanuts are produced annually in the United States. Peanut farmers depend on pesticides to control mite populations. Because TSSM has developed resistance to many acaricides and there are restrictions on the use of pesticides, an alternative approach, such as precision pest management, is needed that would reduce the amount of pesticides that must be applied. This study was initiated to determine whether precision pest management is a feasible management strategy for use against TSSM populations in peanut. Two requirements of the precision management approach are that maps of the spatial distribution of TSSM populations can be developed and the pattern of distribution changes little over time to allow management strategies to be implemented.

To this end, a study of four commercial peanut fields located in two counties of southeastern Virginia was conducted to characterize the spatial distribution of TSSM populations. Intensive sampling of TSSM populations was conducted within each of the fields. The results showed that there was a general increase in TSSM populations during the early phases of sampling. Fields with low densities of TSSM populations had a spatial distribution that was either uniform or random; in fields with relatively higher densities, TSSM populations usually were aggregated. Little or no change in the spatial distribution of TSSM occurred from week to week in all fields that were sampled. Where changes in the distribution were observed, these were apparently caused by the application of a pesticide by the grower.

The study also looked at remote sensing technology as an alternative to intensive sampling within peanut fields. Research was conducted under laboratory conditions to determine whether damage caused by feeding TSSM could be detected spectrally before symptoms become visible. The study showed that after eight days leaves of peanut plants subjected to low soil moisture levels had significantly lower reflectance ratios (mean = 9.4766; a = 0.05) than plants given medium (mean = 10.0186) or high (mean = 10.5413) soil moisture levels. After 10 days, there were significant differences (P < 0.05) in the mean reflectance ratios of peanut leaves exposed to four levels of spider mite densities (0, 5, 10, 20 mites/leaf) and the three levels of soil moisture. However, no significant interaction was observed between soil moisture and spider mite density (P = 0.8710). The mean reflectance ratio for 20 TSSM per leaf was found to be significantly lower than 0, 5, and 10 TSSM per leaf at all levels of moisture (low, medium, and high). The results suggested that remote sensing could be used to detect and map plant damage caused by feeding of spider mites before visual symptoms of damage are observed.

The study also attempted to develop a platform for using remote sensing technology in the field. An Unmanned Air Vehicle (UAV) was evaluated that carried a remote sensing system. The UAV remote sensing system was flown over peanut fields where it captured images, which were analyzed to show the spatial distribution of plant stress. Further studies are needed to relate the distribution of plant stress or damage observed by the UAV with the distribution of TSSM densities within peanut fields. Once this has been accomplished, low-altitude remote sensing could be used as an alternative to sampling for building maps of the spatial distribution of TSSM populations for precision pest management.


Master of Science
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4

Li, Jie. "Évaluation et optimisation des performances des systèmes de production distribution." Metz, 2006. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2006/Li.Jie.SMZ0610.pdf.

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Nous considérons un système de production-distribution composé d’un ensemble d’unités de production et d’entrepôts disposées en série et connectés par des facilités de transport. Chaque entrepôt est contrôlé par une politique donnée de gestion de stock et il est approvisionnée par une unité de production amont de capacité finie. On considère un seul type de produit fini. Le problème à résoudre est de déterminer le meilleur paramétrage de la politique de gestion de stock sur l’ensemble du système tout en prenant en compte les contraintes sur la capacité de production, le taux de service client souhaité et les délais de transport. Nos travaux de recherche ont permit le développement d’une méthodologie d’optimisation des paramètres de gestion du stock basée sur la simulation, qui permet de trouver les paramètres de la politique de gestion du stock qui minimisent le coût sur l’ensemble du système de production-distribution. L’efficacité de l’approche proposée a été vérifiée par des expérimentes numériques
This thesis considers a production-distribution system made up of a set of production sites and distribution centers connected by the transport facilities. Each distribution center is managed by a given stock management policy. The aim is to find the best parameters setting of the stock management policy through the whole network in order to optimize the overall performances of the production-distribution system while taking into account the finite production capacity, the customer service requirement, the transport time, and the random customer demand. The results obtained during this PhD thesis allowed to develop a methodology of optimization for the parameter setting of inventory control policies management in the production-distribution systems. Thus, we proposed a simulation based optimization approach which computes the setting that minimizes the overall inventory cost of the production-distribution system, while taking into account fill rate constraints. The approach iss validated by a large number of numerical experiments
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5

Yang, Lifeng. "Computer relaying for EHV/UHV transmission lines." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/40085.

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As the power systems grow, system connections become more complex. Due to cost and environmental concern, more and more parallel lines and series compensated lines may be installed in the system. In order to efficiently use the transmission network, more nonlinear flexible devices such as the phase shifter and the advanced compensation system will be put into use. Once a fault occurs on such a system, a delay in clearing the fault is usually not permissive. This requires a new generation of relays which have high security and dependability and high operating speed. With the advent of high speed microprocessor and fiber optic communication technologies, it is possible to develop high performance relays. In this dissertation, a new generation of pilot relays and non-pilot relays were developed for a transmission line. The pilot relays include the instantaneous percentage current differential (IPD), the phase comparison and the phasor based percentage current differential (PPD) principles. In the pilot protections the synchronized phasor measurement techniques are employed and digital CT saturation detectors are incorporated. All these schemes in primary protections feature charging current (or shunt current ) compensation. The phasor based principles are designed to work within one and a half cycles; while others based on sample by sample comparison are assumed to work in less than a cycle. The non-pilot relays to be investigated in this dissertation include the fault location based and phase angle based directional distance relays. One cycle data window is used in the phasor calculation. Both the distance relays are assumed to make a trip decision in about one and a half cycles. All algorithms were simulated against different fault conditions using EMTP outputs. The simulation results show all the pilot relay algorithms work well for EHV IUHV transmission lines including the series compensated lines. The fault location based distance relay works well in most cases, but it may give a wrong decision for the close-in fault with the fault resistance and may have a singularity problem. The phase angle based distance relay works very well for different fault conditions and is insensitive to fault resistance. The modified phase angle based distance relay was also developed for the series compensated line. It would not lose the direction for faults with or without fault resistance, either for a compensated system in forward direction, or in an adjacent line in reverse direction. The overreach is within 20% of the protected zone. This relay algorithm is also based on the one-cycle data window DFT, and it can give a reliable trip decision in about two cycles. All pilot relays with a fiber optic link and the phase angle based distance relay can constitute a new generation of protection systems for EHV IUHV transmission lines.
Ph. D.
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6

Koutti, Lahcen. "Étude de la densité électronique des phases paramagnétique et antiferromagnétique des monosulfures NiS, CoS et FeS de structure hexagonale dans l'approximation de la densité locale de spin." Metz, 1999. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1999/Koutti.Lahcen.SMZ9917.pdf.

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Nous avons étudié la densité de l'état fondamental des monosulfures FeS, Cos et NiS dans les phases antiferromagnétique et paramagnétique en utilisant les équations de Kohn-Sham. Ces équations sont représentées dans le formalisme des combinaisons linéaires d'orbitales atomiques (CLOA). Elles sont résolues de façon autocohérente dans le cadre de l'approximation de la densité locale de spin (LSDA), de l'approximation du gradient généralisé (GGA) et de la correction LSDA+ U ou U est l'interaction de Coulomb intra-site. Nous avons utilisé la structure hexagonale idéale de NiAs pour calculer la densité d'états électronique des monosulfures dans les deux phases magnétiques. L'organisation des états électronique doit expliquer la transition semi-conducteur-métal de FeS et NiS et le caractère métallique de CoS à toutes les températures. Dans l'approche LSDA nous avons précisé l'origine de la bande interdite de NiS en évaluant les influences respectives du champ cristallin, de l'énergie d'échange-corrélation et des paramètres du réseau. Nous avons montré que la diminution du paramètre c avait une action prédominante sur la suppression de la bande interdite. Pour FeS la comparaison entre la densité d'états calculée et les spectres de photoémission et de BIS permet l'identification des structures présentés dans les spectres expérimentaux. L'existence d'une bande interdite a pu être montré grâce à l'approximation LSDA + U. Le calcul de la densité d'états de CoS réalisé avec l'approximation LSDA montre que le composé est métallique en dessous et au dessus de la température de Néel. La simple LSDA est apte à décrire les propriétés électriques de FeS, CoS et NiS. Alors que la correction GGA n'apporte pas de modification significative aux résultats LSDA, l'approximation LSDA+U améliore la largeur de la bande interdite et la valeur du moment de spin pour FeS et NiS
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7

Tanonkou, Guy Aimé. "Une approche par relaxation lagrangienne pour l'optimisation d'un réseau de distribution : modèles stochastiques et fiables." Metz, 2007. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2007/Tanonkou.Guy_Aime.SMZ0708.pdf.

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Cette thèse présente les problèmes de conception d'un réseau de distribution stochastique. La première partie présente des modèles de conception du réseau de distribution soumis à des demandes aléatoires et des délais d'approvisionnement aléatoires des fournisseurs. Les modèles sont robustes et intègrent simultanément les décisions stratégiques (localisation des centres de distribution (DCs) et sélection des fournisseurs) et les décisions opérationnelles (gestion des stocks) dans un seul modèle d'optimisation. L'intégration de ces deux décisions entraîne une optimisation globale du réseau via un problème d'optimisation combinatoire NP difficile. Pour résoudre le problème, nous proposons une heuristique basée sur la technique de relaxation lagrangienne. Nous développons une méthode appelée ASGM (Armijo Subgradient Method) pour résoudre le problème dual résultant de la relaxation. Dans la deuxième partie de cette thèse, nous présentons deux problèmes de conception des réseaux de distribution stochastique avec des sites non fiables. Les décisions doivent être prises sous les conditions de disponibilité des sites (DCs et fournisseurs). L'objectif est de minimiser le coût total moyen du réseau de distribution tout en déterminant l'ensemble des stratégies optimales et robustes permettant la meilleure réaffectation des clients (resp. Les DCs) aux DCs (resp. Aux fournisseurs). Nous proposons une méthode d’optimisation Monte Carlo combinée avec une heuristique basée sur la relaxation lagrangienne. Dans cette thèse, les résultats numériques obtenus montrent des bornes lagrangiennes très serrées et des gaps de dualité qui ne dépassent pas 1% pour certaines instances du problème
This thesis deals with the development of models and heuristic algorithms for stochastic distribution network design problems. In the first part, the core decision problem lies in optimally designing a distribution network by finding the optimal distribution centers (DCs) location and the best supplier that would replenish the DCs. The first objective of this project is to join strategics decisions (location of DCs and supplier selection) and operational decision (inventory) in the same optimization model. The goal is to minimize the total fixed location cost, transportation cost, working-inventory cost. The problem is difficult to solve since it integrates all these decisions at the same time with non linear cost function to optimize. We provide an efficient technique which reduces system complexity. The second part of this thesis deals with the design of a distribution network where decisions must be made in the presence of uncertainty. Once the facilities have been constructed in the network, one or more of them may from time to time become unavailable because of some risks. To cope with this uncertain environment, we develop strategic decisions that take into account possible scenarios and strategies need to react when risk events occur. A two-period stochastic programming model is proposed. The goal is to minimize the total first stage cost plus the expected value of the random second stage cost taken trough all scenarios. As solution technique, we propose a Monte Carlo optimization approach combining the sample average approximation scheme and an efficient heuristic based on Lagrangian relaxation to generate efficient solutions and determine tight lower bounds
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8

Kamal, Mohamed. "Contribution à l'étude de la distribution des états électroniques de NiO dans l'état fondamental : utilisation de l'approximation LSDA+U." Metz, 1995. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1995/Kamal.Mohamed.SMZ9504.pdf.

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La distribution des états électroniques de NiO dans l'état fondamental a été étudiée dans le cadre de l'approximation de la fonctionnelle de la densité locale de spin. Tous les électrons y compris les électrons d localises sont décrits par des états itinérants en accord avec la symétrie de translation. Les fonctions d'onde et les énergies sont obtenues par une méthode autocohérente de combinaison linéaire d'orbitales atomiques a spin polarise. A la différence d'un calcul classique, les fluctuations de charge sont prises en compte et se traduisent par un potentiel agissant spécifiquement sur les électrons d. Le terme prépondérant dans ce potentiel est représenté par l'interaction électrostatique intrasite u entre deux électrons. La présence de u modifie la répartition des états électroniques permis et interdits ainsi que le degré d'hybridation des fonctions propres associées. Les résultats montrent des bandes d’occupées étroites et pratiquement toutes séparées. La bande interdite est de valeur comparable à la valeur expérimentale lorsqu'on ajuste l'énergie u a 5. 4 ev. Les fonctions d’occupées et vides sont celles prévues par le champ des ligands applique à un atome dans un environnement cubique. Les bandes 2p de l'oxygène sont en dessous des bandes d peu dispersives du métal et confèrent à NiO le caractère d'isolant de Mott. Cependant les bandes 3d remplies ne sont pas absolument pures car u contribue à accentuer la proportion de fonction 2p de l'oxygène dans ces bandes. C'est grâce à cette présence que notre diagramme théorique d'états électroniques permet l'interprétation de l'ensemble des résultats expérimentaux parmi lesquels l'absorption optique et la photoémission. Enfin l'accord satisfaisant avec les spectres de photoémission angulaire montre l'aptitude de notre démarche a décrire l'état fondamental de NiO
The electronic state distribution of the NiO antiferromagnetic ground state has been studied within the local spin density approximation. All electrons, including the localized 3D electrons, are described by means of itinerant states according to the translational symmetry. The wave functions and energies are obtained self-consistently through a spin polarized linear combination of atomic orbitals method. Unlike a classical calculation, the charge fluctuations have been taken into account and related to a potential acting specifically on the 3D electrons. The main term in that potential is the on-site electrostatic interaction U between two electrons. The presence of U alters the repartition of the allowed and forbidden electronic states as well as the degree of hybridyzation of the eigenfunctions. The results show that the occupied 3D bands are narrow and nearly separated. The calculated gap value is in agreement with the experimental value when U is adjusted to 5. 4 eV. The occupied and empty 3D functions are those predicted by the ligand field applied to an atom in a cubic surrounding. The oxygen 2p bands reside below the small dispersive metallic 3D bands and confer a Mott insulating character to NiO. Nevertheless the full bands are not entirely pure because U enhances the ratio of the oxygen 2p functions within these bands. The theoretical electronic state diagram allows the interpretation of the whole experimental results particulary the optical absorption and the photoemission. Finally the satisfactory agreement with the angular photoemission spectra shows the ability of our approch to describe the ground state of NiO
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9

Weyrauch, Shauna L. "Habitat fragmentation and woodland amphibians consequences for distribution, genetic diversity and fitness responses to UV-B radiation /." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1092668394.

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Анотація:
Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xiv, 138 p. : ill. Advisor: Thomas C. Grubb, Dept. of Evolution, Ecology, and Organismal Biology. Includes bibliographical references (p. 129-138).
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10

Benyahia, Mohamed. "Etude de la contamination du bivalve d'eau douce Dreissena polymorpha par le plomb : bioaccumulation, distribution tissulaire et élimination du métal : incidence de paramètres biotiques et abiotiques." Metz, 1991. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1991/Benyahia.Mohamed.SMZ9112.pdf.

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Les dreissènes exposées au plomb accumulent le métal à des niveaux différents selon la concentration métallique dans le milieu. Les cinétiques de bioaccumulation sont linéaires pour les faibles concentrations de Pb dans le milieu et saturantes pour les concentrations élevées. Les paramètres du milieu agissent sur la bioaccumulation. L'edta réduit fortement la bioaccumulation et la toxicité létale du plomb. Le zinc montre une interaction négative avec le plomb dans la phase initiale de la cinétique de bioaccumulation. La température diminue l'accumulation du plomb en stimulant les processus d'excrétion. Dans une exposition cyclique au plomb, la cinétique de bioaccumulation présente une allure sigmoïde ce qui semble montrer que la dreissène se comporte comme un système à compartiments d'accumulation. Il existe une variation saisonnière de la bioaccumulation. C'est au printemps que la vitesse d'accumulation ainsi que les contenus métalliques des organismes sont les plus importants. Le plomb a pu être localisé histochimiquement et par microanalyse essentiellement dans des granules au sein des cellules rénales, dans le cytoplasme des granulocytes dans les branchies, l'épithélium digestif, la glande péricardiale et dans le byssus. La décontamination est faible et se produit lentement par rapport à l'accumulation. Elle est significativement augmentée en presence d'edta et par une élévation de température. Le niveau de contamination initiale ne montre pas d'influence significative sur les taux de décontamination. La décontamination totale n'est pas atteinte
Freshwater mussels (Dreissena polymorpha) were exposed to lead under laboratory conditions. Patterns of accumulation in whole animals were linear at low concentrations and the tissues lead concentrations were proportional to lead in the medium. At high concentrations of lead in the medium, the accumulation proceeded at a high rate in a saturating mode. Under cyclic conditions of exposure, kinetic of lead accumulation showed a pronounced biphasic mode. It is argued that the biphasic course of accumulation seemed to indicate that the animal acts as a multi-compartments accumulation system. The chelation of lead by EDTA decreased strongly its toxicity and bioaccumulation. In the presence of zinc, uptake of lead in whole Dreissena was reduced in the initial phase of accumulation. Thereafter, the antagonistic effect of Zn decreased and became not significant at the end of exposure period. A rise in temperature decreased lead accumulation by mussels. The results also indicate that accumulation were greatly affected by seasonal conditions. In spring, the rate of uptake was the faster and lead body burden was the most important. By means of histochemical staining method and microanalytical technique (LAMMA), lead has been localized mainly in granules of renal cells and in cytoplasm of granulocytes in gills, pericardial gland, byssal gland and digestive epithelium. The depuration process were low and occured sloly compared to accumulation. The original lead concentrations in the soft parts did not influence significantly the rate of elimination. The presence of EDTA or a rise in tempeature enhanced the rate of lead elimination. In all conditions, the total depuration were not attained and the tissue lead concentrations remained at high levels in comparison to controls
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11

Banks, Bradley. "The System Design of a Global Communications System for Military and Commercial use Utilizing High Altitude Unmanned Aerial Vehicles (UAVs) and Terrestrial Local Multipoint Distribution Service (LMDS) Sites." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/32556.

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This thesis proposes the design of the UAV-LMDS communication system for military and commercial use. The UAV-LMDS system is a digital, wireless communication system that provides service using unmanned aerial vehicles (UAVs) flying at 60,000 ft. acting as communication hubs. This thesis provides background information on UAV-LMDS system elements, a financial analysis, theory, link budgets, system component design and implementation issues. To begin the design, we develop link budgets that are used to characterize system parameters. We present detailed antenna designs for the antennas aboard the UAV. We also present communication equipment block diagrams. Included are technical details on military and commercial geostationary satellites used to link transmissions in the system. Implementation issues in the military system are discussed. Mobility and the effects of vegetation in the propagation path are investigated and a co-channel interference study is done. This thesis shows that by using UAVs and LMDS, a viable, broadband, wireless communications system can be created for military and commercial use.
Master of Science
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12

Roccatello, Andrea. "Planning mobile robot tasks for autonomous UVC-based COVID-19 sanification of public environments with guaranteed minimum energy distribution." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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The present essay shows a solution to automize the sanitization process of public environments with UV lamps. Human planning of the procedure may lead to dangerous consequences in case of errors. Therefore, it was chosen to automatically manage the creation of a path that guides the robot through the rooms avoiding obstacles. The project needs the environment map and the selection of areas where sanitization is required. Velocities are defined using optimization techniques to guarantee the distribution of a minimum energy level in all the areas that need sanitization, considering the limited energy autonomy of the robots due to the UV lamps consumption. To demonstrate the validity of the solutions, it was created a simulation in ROS, where a Turtlebot3-Waffle Pi robot performs the sanitization in a simulated environment. The simulation includes several map layers where it is possible to control the state of the lamps and the energy distribution. Once the simulation is over, a control will be performed to check whether the minimum threshold has been reached.
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13

Peres, José Carlos Gonçalves. "Análise de um reator fotoquímico anular usando a fluidodinâmica computacional." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-15052013-184542/.

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Os processos oxidativos avançados são promissores para a degradação de compostos orgânicos resistentes aos tratamentos convencionais, como o fenol. A fluidodinâmica computacional (CFD) tornou-se uma poderosa ferramenta para analisar processos fotoquímicos por resolver os balanços acoplados de quantidade de movimento, de massa e de radiação. O objetivo deste trabalho é investigar o processo UV/H2O2 num reator fotoquímico anular usando CFD e um modelo cinético mais realista. O modelo em CFD foi criado de forma progressiva. Inicialmente, foram determinados os campos de velocidade para três vazões (30, 60 e 100 L/h). Considerou-se dois diâmetros de lâmpada para reproduzir a configuração experimental do sistema. A discretização foi feita com malhas tetraédricas variando entre 390 000 e 1 200 000 elementos. Quatro modelos de turbulência RANS foram analisados: k-e, k-w, o shear stress transport (SST) e o modelo de tensões de Reynolds (RSM). O campo de velocidades foi validado comparando a DTR com seu levantamento experimental. A próxima etapa foi incluir o mecanismo de degradação de fenol proposto por Edalatmanesh, Dhib e Mehrvar (2008) no modelo em CFD. Trata-se de um modelo cinético baseado em equações dinâmicas para todas as espécies. O campo de radiação foi calculado pelo modelo radial e pela solução da equação de transporte de radiação através do método discrete transfer. As simulações reproduziram dados experimentais abrangendo uma larga gama de concentrações iniciais de fenol, razões molares H2O2/fenol e três potências de emissão das lâmpadas. O campo de velocidades obtido era dependente da vazão: o fluido pode manter movimento helicoidal sobre toda a extensão do reator ou se desenvolver como um escoamento pistonado. O modelo k-e não reproduziu bem o escoamento por não ser adequado para escoamentos rotativos. Os outros modelos geraram curvas de DTR com bom ajuste aos dados experimentais, especialmente o modelo k-w. O desvio médio entre as simulações de degradação de fenol e os dados experimentais é inferior a 8%. Verificou-se que, devido ao escoamento rotativo, os reagentes ficavam concentrados próximos à parede externa e migravam para a região da lâmpada ao longo do reator. A elevada intensidade de radiação na superfície da lâmpada criou uma camada ao seu redor na qual a fotólise do H2O2 ocorreu com grande taxa. Os radicais OH gerados nessa camada eram transportados para a região das paredes por convecção. Isso fez com que a maior parte do fenol fosse atacada na segunda metade do reator e gerou acúmulo do radical próximo à lâmpada na seção de saída do reator, já que o poluente já fora oxidado nessa área. O método discrete transfer previu intensidades de radiação maiores que o modelo radial, e, consequentemente, maior concentração de radicais OH. Os resultados satisfatórios indicam que CFD foi uma ferramenta adequada para analisar este escoamento reativo.
Advanced oxidation processes are a promising technology for degradation of organic compounds resistant to conventional treatments such as phenol. Computational fluid dynamics (CFD) has recently emerged as a powerful tool that allows a deeper understanding of photochemical processes in reactor engineering by solving the coupled momentum, mass and radiation balances. This work aimed to investigate the UV/H2O2 process in an annular photoreactor using CFD and a more realistic kinetic model. A progressive approach was used to develop the CFD reactor model. First, the velocity fields were determined for three volumetric flow rates (30, 60 and 100 L/h). Two lamp diameters were considered to reflect the experimental configuration of the system. Tetrahedral meshes varying form 390,000 to 1,200,000 elements were analyzed to achieve grid independence. For accounting turbulence effects, four RANS models were tested: k-e, k-w, the Shear Stress Transport (SST) and the Reynolds Stress models (RSM). The velocity field was validated through comparison to RTD experimental data. Next step was introducing the mechanism of phenol degradation proposed by Edalatmanesh, Dhib and Mehrvar (2008) into the CFD model. This kinetic model is based on dynamic equations for all species. The fluence rate field was calculated by the radial model and by solving the radiation transport equation with the discrete transfer method. Simulations reproduced experimental data spanning a wide range of initial phenol concentrations, H2O2/phenol molar ratios and three values for lamp power. It was found that the velocity field depends on the volumetric flow rate: either it maintains a swirling motion through the whole reactor or might develop like a plug flow. The k-e model did not represent the RTD data accurately, and the velocity field therefore, since it is not appropriate for swirling flows. The other turbulence models showed good match of RTD, especially the k-w model. Simulations of phenol degradation deviated less than 8% from experimental data. It was possible verified that, due to the swirling inlet effects, reactants got concentrated close to the outer wall and migrated on the lamp direction along the reactor path. High radiation intensities close to the lamp surface created a layer around it where photolysis of H2O2 took place with higher rates. OH radicals were generated in that layer and transported towards the outer wall by convection. This caused most of phenol to be consumed in the second half of the reactor and accumulation of the radical near the lamp and the reactor outlet, since the pollutant in this area was already oxidized. The discrete transfer method predicted higher incident radiation intensity than the radial model, and higher concentrations of OH radicals as a consequence. Satisfactory results indicated that CFD was an appropriate tool for analyzing this reactive flow.
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14

Kim, Yong-Rae. "Integrated Uv-Vis Multiangle-Multiwavelength Spectrometer For Characterization Of Micron And Sub-Micron Size Particles." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/723.

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Characterization of micron and sub-micron size particles requires the simultaneous measurement of the joint particle property distribution (JPPD). The JPPD is comprised of particle size, shape, orientation, composition, optical properties, and surface properties. Measurement of each of the particle properties independently is a difficult task and it has been only partially successful. To determine as many particle properties as possible using optical methods it is necessary to simultaneously measure all aspects of the interaction of the incident light with the particles of interest. This approach leads to the concept of multidimensional spectroscopy suggested by Prof. Garcia-Rubio. Dr. Bacon proved the proposition by developing and testing a prototype multianglemultiwavelength (MAMW) spectrometer proposed by Prof. Garcia-Rubio. However, the prototype MAMW spectrometer has limitations in the amount of information it can obtain because of strong absorption of deep UV light and detector saturation due to the use of optical fibers and single integration time for the CCD detector. The Integrated UV-VIS MAMW spectrometer has been developed to overcome the limitations of the prototype MAMW spectrometer. Improvements have become possible through the use of UV lenses and integration time multiplexing (ITM). The Integrated UV-VIS MAMW spectrometer has the capabilities to perform low angle scattering measurements starting from 4o with simultaneous detection of multiwavelength light from 200 nm to 820 nm, UV-VIS transmission spectroscopy, and frequency domain fluorescence spectroscopy. Following the development, possible sources of errors were analyzed and data calibration procedures have been established to ensure the validity and reproducibility of the measurement results. The capabilities of the Integrated UV-VIS MAMW spectrometer were tested by measuring UV-VIS MAMW spectra of polystyrene standards. The measured UV-VIS MAMW spectra clearly show differences due to particle size, shape, and compositional changes. Measurements of the UV-VIS MAMW spectra of sickled whole blood samples demonstrate that particle shape and compositional changes can be detected simultaneously. These results confirmed that the Integrated UV-VIS MAMW spectrometer could be a powerful tool for the characterization of micron and sub-micron size particles. Alternate approaches to enhance these capabilities further, i.e., the development of a new multidimensional MAMW spectrometer, are also described.
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15

Михальонок, О. С. "Дослідження та аналіз текстури тканини з використанням сучасного об’єктно-орієнтованого програмування в задачах моделювання". Thesis, Київський національний університет технологій та дизайну, 2018. https://er.knutd.edu.ua/handle/123456789/11203.

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16

Minnis, Rochelle J. "Comparison of the use of single and multiple oxidants on the generation of particulate matter in water distribution systems derived from groundwater sources containing hydrogen sulfide and dissolved organics." [Tampa, Fla] : University of South Florida, 2005. http://purl.fcla.edu/usf/dc/et/SFE0001390.

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17

Bastien, Nathalie. "Fréquence et distribution des dimères cyclobutyliques de pyrimidines suite à une exposition aux UV et évaluation de l’effet protecteur de l’acide sulfonique 2-phénylbenzymidazole-5." Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/6835.

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Résumé : L’exposition aux rayons ultraviolets (UV) du soleil est le principal facteur menant au développement du cancer cutané. Les dimères cyclobutyliques de pyrimidines (DCP) résultant d’une exposition aux UV sont considérés comme les principaux dommages à l’ADN impliqués dans la cancérogenèse cutanée. La fréquence des DCP et leur distribution entre les quatre types de sites dipyrimidiniques ont souvent été étudiés in vitro ou en utilisant des UVC alors que nous ne sommes pas exposés à ce type d’UV. L’utilisation d’écrans solaires permet de prévenir la formation des DCP. Grâce à sa capacité à absorber les UVB, l’acide sulfonique 2-phénylbenzymidazole-5 (PBSA) est utilisé dans des écrans solaires mais des études in vitro ont montré qu’il peut oxyder les guanines lors d’une irradiation aux UVB. Face à ces problèmes, nous avons choisi d’étudier l’effet du PBSA, la fréquence et la distribution des DCP, de même que l’influence de la séquence nucléotidique sur la formation des DCP, dans des conditions plus représentatives de la réalité. Nous avons irradié des fibroblastes humains normaux (in cellulo) et de l’ADN purifié (in vitro) aux UVB et aux UVC. Nous avons comparé la formation des DCP in cellulo et in vitro. Suite à une exposition aux UVB, nous avons trouvé que la distribution des DCP in cellulo est similaire à la distribution des DCP in vitro. Nous avons ensuite comparé l’effet du type d’UV sur la formation des DCP et nous avons trouvé que les TT sont plus souvent endommagés après une irradiation aux UVC alors que les sites potentiellement mutés (contenant des cytosines) sont plus souvent endommagés après une exposition aux UVB, in cellulo. Concernant l’effet de la séquence d’ADN sur la formation des DCP, nous avons trouvé que certains sites dipyrimidiniques sont beaucoup plus fréquemment endommagés que les autres et que la position d’un site dipyrimidinique dans une série de pyrimidines adjacentes est un facteur influençant la formation des DCP. Nous avons étudié l’effet du PBSA in cellulo et in vitro suite à une irradiation aux UVA et aux UVB. Nous avons montré que le PBSA protège efficacement contre la formation de DCP, lors d’une irradiation UVB mais qu’il photosensibilise la formation de guanines oxydées lors d’une irradiation aux UVA et aux UVB. Le PBSA peut donc agir comme une épée à double tranchant et ceci questionne son utilisation dans les écrans solaires. Les travaux réalisés dans le cadre de cette thèse améliorent notre compréhension de la cancérogenèse cutanée, montrent l’importance du choix de modèles d’étude pertinents, de même que l’importance d’utiliser une protection solaire efficace contre tous les types de dommages causés par les UV.
Abstract : Exposure to the UV component of sunlight is the principal factor leading to skin cancer development. Cyclobutane pyrimidine dimers (CPD) are considered as the most important DNA damage involved in skin carcinogenesis. CPD frequencies and their distribution between the four types of dipyrimidine sites are mostly investigated in vitro or using UVC, even if we are not exposed to these wavelengths. On the other hand, sunscreens are used to protect against CPD formation. The 2-phenylbenzimidazole-5-sulfonic acid (PBSA) is a sunscreen agent used because it absorbs UVB. However, previous studies have shown that PBSA oxidizes guanines in vitro, during UVB exposure. To address these issues, we chose to study the effect of PBSA, the DCP frequencies and their distribution frequency and distribution of CPD, as well as the influence of DNA sequence on CPD formation, in conditions more representative of reality. We irradiated normal human fibroblasts (in cellulo) and purified DNA (in vitro) with UVB and UVC. We compared the CPD distribution in cellulo and in vitro. Our results show that CPD distribution in cellulo is different to CPD distribution in vitro after UVB exposure. Then, we compared the impact of UV type on CPD formation and we found that TT are more frequently damaged after UVC exposure while potentially mutated dipyrimidine sites (dipyrimidine sites containing cytosine) are more frequently damaged after UVB exposure. Concerning the influence of DNA sequence on CPD formation, we observed that some dipyrimidine sites are extremely frequently damaged compared to others and that the position of a dipyrimidine site within a dipyrimidine run is an important factor influencing the frequency of CPD formation. We studied the effect of PBSA, in cellulo and in vitro, during UVA and UVB exposure. We found that PBSA provides good protection against CPD formation during UVB exposure, in cellulo. However, PBSA photosensitized the formation of oxidized guanines during UVA and UVB exposure. This indicates that PBSA can act as a double-edged sword and question its suitability in sunscreens. The works presented in this thesis provide important elements to understand the skin carcinogenesis process and demonstrate the importance to use an effective protection against UV-induced DNA damage.
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18

Postal, Victor. "Estudo da degradação térmica de emulsões via espectroscopia UV-Vis aplicado a fluidos de corte." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-23012017-113619/.

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O monitoramento de emulsões utilizadas na indústria metalmecânica compõe uma importante atividade para o controle da qualidade das peças trabalhadas, proporcionando também o aumento da vida útil de ferramentas e maquinários utilizados neste setor através da lubrificação e refrigeração da região de corte. Em grande parte dos casos, estas emulsões são preparadas pela diluição de um fluido de corte em meio aquoso, constituindo assim um conjunto de gotículas estabilizadas em um meio contínuo devido à presença de compostos emulsificantes, estando constantemente sujeitas a ciclos de aquecimento e resfriamento durante os processos de usinagem. Apesar do acompanhamento deste material ser realizado através de análises periódicas usuais, não há um método eficiente estabelecido para verificar sua qualidade em tempo real e em linha de processo. Neste contexto, torna-se possível aplicar técnicas relacionadas à espectroscopia UV-Vis para se obterem informações sobre a estabilidade destes sistemas, correlacionando intensidades de espalhamento de luz com as dimensões das gotas presentes no meio. Dessa forma, tornou-se possível o estudo da desestabilização térmica de emulsões de um fluido de corte comercial, a qual mostrou-se, através do acompanhamento do cálculo do expoente do comprimento de onda, dependente do tempo de exposição ao aquecimento e de sua temperatura média temporal, não sendo influenciada pela perda de meio contínuo por processos evaporativos ou sua posterior reposição. Também se verificou que parâmetros típicos do processo de preparo de emulsões, como a temperatura do meio dispersante e o tempo de repouso do fluido de corte sobre a superfície do mesmo, apresentam fundamental importância para a definição do tamanho médio de gota inicial destes sistemas, o que forneceu evidência da possibilidade de se relacionar a área sob espectros de extinção de luz com tamanhos médios de gota.
The monitoring of emulsions used in the metal-mechanical industry comprise an important activity to the quality control of the products manufectured, also providing an increase in the working life of the tools and machinery employed in this sector through the lubrication and refrigeration of the cutting zone. In the majority of cases, these emulsions are prepared diluting a metalworking fluid in an aqueous media, constituting a collection of particles stabilized by emulsifiers and undergoing heating and cooling cycles during metalworking processes. Currently, monitoring routines are based on regular analyses of samples taken from the process fluid, and an effective in-line method is not available to monitor emulsion quality in real time. In this context, it is possible to apply techniques related to UV-Vis spectrocopy in order to obtain information concerning the stability of those systems, correlating light scattering intensities to the droplet dimensions. In this study, it was possible to investigate the thermal destabilisation of a commercial metalworking fluid emulsion, which showed, through the evaluation of the wavelength exponent, to be dependant on the exposure time to heating and its time-averaged temperature. It was also noted that the loss of continuous phase by evaporation and its reposition do not affect the emulsion stability. Moreover, it was observed that important emulsion preparation parameters, such as continuous phase temperature and the time span between the addition of the metalworking fluid on the water surface and the stirring, have fundamental roles in defining the initial average droplet size, which made possible to correlate the area under the light extinction spectra with average droplet sizes.
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19

Therrien, Jean-Philippe. "Photocarcinogenèse, distribution des dimères cyclobutyliques de pyrimidines à l'ADN après irradiation aux UV et rôle de p53, pRb et p21waf1 dans leur réparation par excision de nucléotides." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0015/NQ54033.pdf.

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20

Roleda, Michael Y. "Effects of ultraviolet radiation on early life stages of cold temperate and Arctic macroalgae : implications for recruitment and vertical depth distribution = Effekte von UV-Strahlung auf frühe Lebensstadien kaltgemässiger und arktischer Makroalgen : Auswirkungen auf Rekrutierung und Vertikalverteilung /." Bremerhaven : Alfred-Wegener-Institut für Polar- und Meeresforschung, 2006. http://www.loc.gov/catdir/toc/fy0703/2006499119.html.

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21

Ahuja, Nandita. "Impact of operating conditions on thermal hydrolysis pre-treated digestion return liquor." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/56647.

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Return liquor from thermal hydrolysis process (THP) can significantly add to the nitrogen load of a wastewater treatment plant (WWTP) and introduce UV quenching substances to the wastewater stream when recycled. While there are mature technologies in place to handle the inorganic nitrogen produced due to the thermal pretreatment, organic nitrogen remains a parameter of concern for utilities employing THP pretreatment. The impact of operating conditions of the THP on dissolved organic nitrogen (DON) and UV absorbance in return liquor was investigated. Operating conditions studied were (1) operating temperature (2) solids retention time (SRT) in the anaerobic digester (3) THP flash pressure (4) the effect of co-digestion of sewage sludge with food waste and, (5) polymer conditioning. Operating temperature and polymer dose had the most significant impact on DON and UV quenching. It was found that an increase in operating temperature resulted in an increase in DON, which was primarily contributed by the hydrophilic fraction. An increase in temperature also resulted in increased UV254 absorbance. However, this trend was not linear and the increase was more pronounced when the temperature was increased from 150 C to 170 C. Increasing flash pressure from 25 psi to 45 psi did not have a significant impact on the return liquor. However, increasing the flash pressure to 75 psi increased the DON and UV254 absorbing compounds. Co-digesting the sludge with food waste resulted in a slight increase in DON and a decrease in dissolved organic carbon (DOC) and UV quenching compounds. Increasing the SRT from 10 days to 15 days resulted in a slight decrease in DON but did not have any impact on UV254 absorbance. Overall, it can be concluded that optimizing operating conditions of thermal hydrolysis process can result in decreased DON and UV quenching compounds in the recycle stream.
Master of Science
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22

Reynal, François. "Etude des processus non-linéaires dans les atomes complexes en interaction avec un champ XUV intense et bref." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2012. http://tel.archives-ouvertes.fr/tel-00748138.

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Etude th'eorique de l'interaction entre un atome à deux ou trois électrons actifs et un champ laser de fort éclairement (10^13 à 10^15 W.cm−2) et de durée d'impulsion ultra-brève (femto à attoseconde) dans le domaine spectral XUV. Notre approche est basée sur la résolution de l' équation de Schrödinger dépendante du temps (ESDT). Nous utilisons une méthode spec- trale pour résoudre l'ESDT avec des fonctions d'onde construites sur des B- splines. Nous étudions particulièrement la double ionisation à deux photons (TPDI) de l'hélium dans l'état fondamental ainsi que dans l' état excité 1s2s. Plusieurs modèles sont d'eveloppés pour traiter le cas des impulsions ultra- brèves. Enfin nous abordons la TPDI du Lithium, système à trois électrons actifs. Nous comparons la double ionisation à deux photons dans le régime séquentiel pour Li et He(1s2s) ; le régime direct est également abordé
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23

Sarda, Estève Roland. "Étude de la variabilité des bioaérosols atmosphériques en région île de France." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASJ004.

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Les bioaérosols atmosphériques sont des particules d’aérosols biologiques primaires en suspension dans l’air et référencés dans la littérature comme étant des: Primary Biological Aerosol Particles (PBAPs). Les PBAPs sont de tailles et de natures très différentes. Ils ont la capacité à agir comme noyaux de condensation nuageux ou de glace et participent ainsi au cycle de l’eau sur terre. Ils peuvent être transportés loin de leur zone d’émission et coloniser de nouveaux écosystèmes. Leur caractère allergisant ou pathogène a un impact sur la santé humaine et animale. Ce travail de thèse qui porte sur l’étude de la variabilité des bioaérosols atmosphériques en région île de France concerne les pollens, les moisissures et les bactéries. Les observations ont été réalisées dans la couche limite à l’observatoire du SIRTA/LSCE. Ce travail pionnier dans la région Francilienne a permis: (1) de documenter la variabilité interannuelle, saisonnière et journalière propre à chacun des PBAPs, (2) de déterminer leurs origines géographiques respective, (3) d’étudier les paramètres météorologiques qui gouvernent leur cycle de vie dans l’atmosphère. Mon dernier objectif (4) a été de developper un instrument de mesure en temps reel des PBAPs et plus specifiquement des pollens
Atmospheric bioaerosols are particles of primary biological aerosols suspended in the air and referred in the literature as: Primary Biological Aerosol Particles (PBAPs). PBAPs have very different sizes and coposition. They have the ability to act as cloud condensation nuclei or ice nuclei and thus participate in the water cycle on earth. They can be transported far from their sources and they can in this way colonize new ecosystems. Their allergenic or pathogenic propoeries have an impact on human and animal health. This work on the variability of atmospheric bioaerosols in the Ile de France region concerns pollens, molds and bacteria. The observations were made in the boundary layer at the SIRTA/LSCE observatory. This pioneering work in the Ile-de-France region had the objective to: (1) document the interannual, seasonal and daily variability specific to each of the PBAPs, (2) determine their respective geographical origins, (3) study the meteorological parameters that control their life cycle in the atmosphere. My last objective (4) has been to develop an on line instrumenst to measure in real time BPAPs concentrations with a focus on pollen
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24

YADAV, ASTHA. "ANALYSIS OF EXTREME RAINFALL EVENT IN THE METEOROLOGICAL SUBDIVISION OF UTTAR PRADESH USING THREE-PARAMETER EXTREME VALUE DISTRIBUTIONS." Thesis, 2020. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18151.

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Extreme rainfall is a global phenomenon occurring in almost every major country of the world that cause significant damage such as floods and erosion that can destroy infrastructure, human and animal life, disruptive economic activities, and related development. The forecasts of heavy rainfall help to implement strategies, and measures before they occur. In this study, we used statistics strategies to create models that could work to predict maximum rainfall in Uttar Pradesh. For this purpose, the annual maximum rainfall from 1979-2018 applies in the subdivision of Uttar Pradesh. Extreme value distribution GEV, GLO, GPA, and UEV considered analyzing extreme events. The parameters of the 1st three distribution are determined using the method of moment (MOM) and probability-weighted L- moment (PWM-L). The last distribution parameters are determined using the simple objective method (SO). Two methods used to analyze the best fit distribution among four distribution, i.e., graphical method (coefficient of determination, R2 ), and goodness of fit test (GOF). Five different GOF tests apply in this study, i.e., RRMSE, RMSE, MAE, MADI, and PPCC. Basic time series analysis such as outliers test, normality test, homogeneity test, and stationarity tests performed to ensure that the information used is adequate and appropriate. The results obtained indicate that the GEV (PWM-L) was an appropriate method for the distribution of the annual maximum rainfall series in the west Uttar Pradesh subdivision and the GLO (PWML) which was an appropriate distribution method to analyze the series of the East Uttar Pradesh subdivision. The coefficient of determination (R2 ) for the observed versus predicted rainfall based on the best fit model observed to be 0.9899 and 0.9865, respectively, West Uttar Pradesh subdivision and East Uttar Pradesh subdivision. Finally, the most appropriate distribution at each site applies to predict maximum rainfall at different return periods.
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25

HSIEH, MENG-CHIN, and 謝孟錦. "The Characteristics of UV Index Distribution in Taiwan." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/py26e8.

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碩士
大仁科技大學
環境管理研究所
104
The purpose of this study was to investigate the Temporal and Spatial characteristics of ultraviolet (UV) index in north, central, south, east regions, and offshore islands of Taiwan and further compare Taiwan’s UV readings with Australia. Results showed that Taiwan's UV readings are higher in summer and lower in winter. In summer, UV readings concentrate at the very high radiation level, and readings above the high level account more than 50%. In winter, UV readings concentrate at the moderate or low level, but readings at the extreme level may also occur in high mountain areas. Besides, regional distributions and variations of UV radiation levels are similar across Taiwan, where moderate readings account for the majority, followed by very high readings and high readings in similar ratios. The ratio of high readings is highest in central and south Taiwan and lowest in north Taiwan; the ratio of very high readings is higher in central, south, and east Taiwan and lower in north and offshore islands of Taiwan; in terms of extreme readings, east Taiwan has the highest ratio, followed by central and south Taiwan, while north Taiwan has the lowest. As to distribution of radiation levels in areas of high concern, the monitoring station in Pingtung shows high level > moderate > very high > extreme > low level in the area. The high level readings take 67% annually and 86.2%~97.4% from May to August. The monitoring station in Kenting showed very high > moderate > high > extreme = low level in the area. Readings above the high level account for 65.4% annually and 73.3%~96.7% from April to October. In high mountain areas, Tataka and Mt. Jade stations have respectively detected a UV index of 11 or higher in 84 and 118 days, even during winter times. The highest UV index ever recorded in Mt Ali is 8 and that in Sun Moon Lake is 12. Finally, comparison of UV index in Taiwan and Australia in the same time periods showed that Alice Springs has higher monthly average and annual average than Taiwan. In terms of annual average, the index in Australia is 1.45 times of the index in Taiwan.
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26

Cheng, Yuan-Kang, and 成元綱. "Angular distribution of UV-pumped phosphor-converted LED." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/77598932923321399410.

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Анотація:
碩士
國立東華大學
光電工程學系
99
White LED based on phosphor conversion an important approach for energy saving and mercury-free lighting in the near future.Two approaches have been proposed for phosphors converted white LED using either the blue or UV LEDs for pumping light. The blue pumped Nd:YAG LED has the advantage of high efficiency but the CRI is limited and the uniformity in angular distribution is poor. UV converted LED on the other hand have better CRI and angular distribution but the efficiency is limited. To over this low efficiency, an omni-directional coating approach is proposed previously to increase the efficiency of the UV-pumped LED. An one dimensional model is constructed to determine the material parameters and to analyze the performance. However one dimensional model is unrealistic since the advancing wave front of light propagation is the sum of the all the point sources in the medium already traversed, according to Huygen’s principle. In the present result an investigation of the angular distribution of the UV pumped LED is performed. A quasi three dimensional (Q3D) model based on the observed data is constructed to analyze the angular distribution of measured data with different material parameters. Based on the angular distribution of phosphor-converted light, it is found that the angular distribution can be influenced by the phosphors layer thickness, concentration, ODR brightness enhancement layer, and back reflection. Angular distribution of the phosphors converted light is isotropic in the media it is generated which forms a near lambertion pattern when measured outside the media. The details shape of the emitted light depends on the refractive index differences of the effective index in the media in which they are generated and where they are observed. Thus a quasi-3D model is constructed with the primary source follow the Beer-Lambert law with a exponential decay inside the media and the loss in light is absorbed by the phosphors to generated the isotropic ally distributed light at a lower wavelength. This generated light is then absorbed by the media before they escaped the media. The validity of the model is established by fitting the measured data and then is used to explain the observed behavior of the angular distribution of the emitted light which are summarized below: 1.As the thickness increased, the distribution deviate more from the lambertian distribution since the light emitted at an angle after absorption of UV photon will travel a longer path in the phosphor layer and will experience a larger attenuation, thus less light is emitted. This attenuation increases with angle and resulted in a narrower distribution than the lambertian distribution. For the same reason, the beam also becomes narrower as the concentration increases. 2.For the ODR covered sample, the deviation becomes less since more UV light is converted near the top of the phosphor layer with the ODR present to reflect the UV light. Being generated near the top, this part of light has shorter path and has wider distribution than that generated near the bottom of the layer, thus the combined light appears wider for the high angle light and the deviation from lambertion with thickness appear to be less than that without the ODR. The same trend is observed with the concentration. 3.For the case with the back-reflector in the package to reflect the backward propagating, light from the top of the phosphor layer travels a longer distance and its contribution becomes less. But that generated at bottom are making bigger contribution as they are experiencing less attenuation. The angular distribution of the combined light narrows. Good quantitative fit with the measured data are obtained that validate the model. The material parameters used for the fit including the absorption coefficient of the pumped light and the converted light is compared with that obtained with the 1D model. It is found that the 1D model over-estimated the primary light since the distance traveled for the 1D model is shorter than the Q3D model. In summary, the factors that can influence the angular distribution of the light from the UV pumped phosphor converted LED are analyzed qualitatively in the present work. The influence of these factors are quantitatively analyzed by taking into account the path length variation as light travel at an angle through the phosphor layer.
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27

Chen, Po-jui, and 陳柏瑞. "A Study of Internal Flow and Temperature Distribution of UAV Engine Cowling." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/64y7gj.

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28

ZHAO, LI-YIN, and 趙立愔. "A Research on Logistics Distribution Path Planning for Using Unmanned Aerial Vehicle(UAV)." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/7rfuz8.

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Анотація:
碩士
世新大學
資訊管理學研究所(含碩專班)
105
In 2013, Amazon announced that it would use UAV to do home delivery services in the future. From that time many countries of logistics industry in the world began to research the area of UAV on logistics service. However, the Federal Aviation Administration's newly-proposed drone guidelines have strict restrictions of using UAV for delivery services in the United States. The UAV flight environment belongs to 3D environment which is different from the traditional path planning for 2D environment. Therefore, in this research explores the UAV using in delivery logistics, hoping this study would provide decision makers a better choice about the arrangement of the UAV’s path planning after the relevant rules of International Air Traffic Regulation are allowed and the UAV capability has progressed. Practically, the logistics center usually has more than one conveyance to do delivery services in real life. With the change of order groups and the individual destination in this research uses K-means for clustering order groups at first, and Multiple Traveling Salesman Problem (MTSP) is regarded as solution of this study. As MTSP is a complex combination optimization problem, it is very difficult to find out optimal solution in polynomial time, and its calculation times will be with problem complex degrees into index growth. Therefore, in this study will use Genetic Algorithm (GA) to find out the path planning of UAV. GA’s characteristics of parallel multiple-point search can upgrade execution efficiency. The system is designed into four parts, order clustering, clustering TSP, genetic algorithm, and customer service level analysis. First, order clustering would use K-means for clustering order groups. And then the clustering result would execute TSP calculation for obtaining the first result of initial population. And other results of initial population are based on the first result randomly generated. Second, genetic algorithm design would start chromosome encoding used two-part chromosome technique, and customer service level is used define fitness function. The method of selection and reproduction adopts binary tournament selection method. Two-part chromosome crossover is used in Crossover and swap mutation is adopted in Mutation. The termination condition is set by the number of iterations. Finally, we would carry out customer service level analysis, if the result of path planning for UAV is within the customer service level, operation is ended. Otherwise, we will increase a UAV for delivery services, and one group will be added and clustering order groups again. This study has been proved to obtain an effective result. The decision maker could make decision easily by this model in the future.
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29

Hsu, Sheng-Ya, and 許聖亞. "Distribution of Light Emission from UV-pumped Phosphorous Converted Green LEDs." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/28066799002006255304.

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Анотація:
碩士
國立東華大學
光電工程學系
101
The present thesis is the extension of the previous mater degree theses on the subject of the angular distribution and the modeling of the light generation by near UV light excitation of phosphors layers. In the present work, near parallel UV light incident at various angles to the phosphor layers are investigated. The use of parallel light, rather than the divergent light as before, is because it allow a better comparison with the experimentally measured angular distribution to determine the material constants for the phosphor layer. The more general case of divergent light incidence can be treated as a superposition of the parallel lights. The angular distribution of the emitted fluorescent light are measured as a function of the incident angle, the concentration and the thickness of the phosphor layers. The result shows that the angular distribution of the phosphorescent light, in the range of interest for lighting, is near Lambetian regardless of the incident angle, the thickness and concentration of the phosphor layers. This indicates that the phosphorescent light is emitted from the phosphor particles, on average, in an isotropic manner. The small deviation can be accounted for by the absorption of phosphorescent light by the phosphor layers. The 3D model developed so far can be used to account for these deviations from Lambertian distribution. The present work can find application in the UV converted white LED for lighting and displays. It can also find application for the other color such as the green LED. Since the green light range lies on the edges of the nitride technology for blue light generation and the phosphite technology for red light, UV phosphor conversion is a promising solution for this green gap.
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30

Huang, Po-Chun, and 黃柏竣. "Investigating the vertical distribution of air pollutants by UAV platform and performance evaluation of aerosol instruments." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9a9ub4.

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Анотація:
碩士
國立中央大學
環境工程研究所
107
This study presents the helicopter unmanned aerial vehicle (UAV) equipped with different sensors for investigating the vertical distribution of atmospheric aerosols. High temporal and spatial resolution measurements within the first 500 m of atmosphere are presented. Five minimized instruments, including Mixing condensation particle counter, Portable optical particle counter, PM sensor, Aethalometer, parallel-plate differential mobility analyzer, were tested. The performance is calibrated under different environmental conditions. Four flights were conducted on November 15, 2018, from 11:37 pm to 12:10 pm (GMT+8) and December 6, 2018, from 09:48 pm to 10:32 pm (GMT+8). The first two flights fly up to 200 m, and the other two are up to 500 m. The cabinet with aerosol instruments was mounted at the bottom of UAV. Vertical profiles of aerosol particle number concentration, particle size distribution, black carbon mass concentration, PM2.5 were shown.
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31

Yao, Yi-Chun, and 姚逸駿. "Effect of Pre-oxidation on Molecular Weight Distribution by H2O2/UV Process." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/23119750490198193178.

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Анотація:
碩士
淡江大學
水資源及環境工程學系
89
The wastewater samples studied in this paper were taken from the secondary effluent of a textile wastewater treatment plant. The experiments were conducted in a UV reactor under different conditions, including pH, H2O2 dosage, and UV intensity. At different time intervals, the treated wastewater samples were withdrawn for the analyses of residual DOC, color, and the size distribution of organic molecules. Results show that HO‧ reacts with the color-forming species much faster than with the carbonate species. Hence, if the color removal is the main focus, it appears that there’s no need to control the pH. But the pH controlled within acidic range is required to achieve a higher DOC removal. At a low H2O2 dosage of 50 mg/L and a low UV power of 64 watts, the DOC removal was only 30% for pH 4 and 5% for pH 7. The percentages of molecular weight (M.W.) distribution of DOC for the untreated water sample are 57% (0.45 μm-10 KD), and 28%(< 1 KD). Furthermore the portion with the M.W. of 0.45 μm-10 KD decreases from 11.7 (untreated sample) to 5.8 and 2.9 mg/L (treated at pH 7 and pH 4, respectively); the percentages of reduction were 50 and 75%. On the other hand, the portion with the M.W. than 1 KD increases from 5.7 (untreated sample) to 8.8 and 10.2 mg/L (treated at pH 7 and pH 4, respectively); the increasing percentages were 54 and 79%. In addition, the first order reaction constant of color (KC) increases with the increase of H2O2 doses. The KC value increases 3.6 times as the H2O2 doses increase from 50 mg/L to 100 mg/L. In contrast, the KC values increase 1.4 times as the UV intensity increase from 64 Watts to 128 Watts. Therefore, H2O2 doses is more improver treatment efficacy than ultraviolet. In conclusion, the use of H2O2/UV process is promising in treating the secondary effluent of textile wastewater, in terms of DOC and color, for the purpose of wastewater reclamation.
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32

Liu, Dong. "Numerical simulation of UV disinfection reators impact of fluence rate distribution and turbulence modeling /." 2004. http://www.lib.ncsu.edu/theses/available/etd-12282004-161449/unrestricted/etd.pdf.

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33

(11147142), Jialei Wang. "Automated Leaf-Level Hyperspectral Imaging of Soybean Plants using an UAV with a 6 DOF Robotic Arm." Thesis, 2021.

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Анотація:

Nowadays, soybean is one the most consumed crops in the world. As the human population continuously increases, new phenotyping technology is needed to help plant scientists breed soybean that has high-yield, stress-tolerant, and disease-tolerant traits. Hyperspectral imaging (HSI) is one of the most commonly used technologies for phenotyping. The current HSI techniques include HSI tower and remote sensing on an unmanned aerial vehicle (UAV) or satellite. There are several noise sources the current HSI technologies suffer from such as changes in lighting conditions, leaf angle, and other environmental factors. To reduce the noise on HS images, a new portable, leaf-level, high-resolution HSI device was developed for corn leaves in 2018 called LeafSpec. Due to the previous design requiring a sliding action along the leaf which could damage the leaf if used on a soybean leaf, a new design of the LeafSpec was built to meet the requirements of scanning soybean leaves. The new LeafSpec device protects the leaf between two sheets of glass, and the scanning action is automated by using motors and servos. After the HS images have been collected, the current modeling method for HS images starts by averaging all the plant pixels to one spectrum which causes a loss of information because of the non-uniformity of the leaf. When comparing the two modeling methods, one uses the mean normalized difference vegetation index (NDVI) and the other uses the NDVI heatmap of the entire leaf to predict the nitrogen content of soybean plants. The model that uses NDVI heatmap shows a significant increase in prediction accuracy with an R2 increase from 0.805 to 0.871. Therefore, it can be concluded that the changes occurring within the leaf can be used to train a better prediction model.

Although the LeafSpec device can provide high-resolution leaf-level HS images to the researcher for the first time, it suffers from two major drawbacks: intensive labor needed to gather the image data and slow throughput. A new idea is proposed to use a UAV that carries a 6 degree of freedom (DOF) robotic arm with a LeafSpec device as an end-effect to automatically gather soybean leaf HS images. A new UAV is designed and built to carry the large payload weight of the robotic arm and LeafSpec.

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34

Nahler, Nils Hendrik. "Photodissoziation von Halogenwasserstoff- und orientierten Wasserstoff-Edelgas-Halogen-Molekülen in Clusterumgebungen." Doctoral thesis, 2002. http://hdl.handle.net/11858/00-1735-0000-0006-B431-7.

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