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Dissertations / Theses on the topic 'Ion engines'

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Published: 4 June 2021
Last updated: 12 February 2022

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1

Starling, Dan A. "Propellant feed control for ion engines." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA316748.

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2

Starling, Dan A. Jr. "Propellant feed control for ion engines." Thesis, Monterey, California. Naval Postgraduate School, 1996. http://hdl.handle.net/10945/8868.

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An overview of space electric propulsion (SEP) is presented. Methods of throttling the power levels of electrostatic and electromagnetic thrusters are discussed. Particular attention is given to the concept of thermally- throttling propellant flow using the temperature-viscosity characteristics of xenon gas. The thermoproperties of xenon gas as a function of temperature are determined, and the flow regimes of the propellant at the mass flow rates of interest are studied. The propellant flow is presented separately as Fanno flow and as Rayleigh flow, and then those combined effects are considered. A method for predicting the performance of thermally-throttled systems is presented. Uncertainties in modeling real-world thermal throttling systems are discussed. The possible use of thermal throttling characteristics as a means of propellant pressure regulation is also examined.
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3

Gruber, J. R. "A study of erosion due to low-energy sputtering in the discharge chamber of the Kaufman ion thruster." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249396.

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4

Panousakis, Dimosthenis. "Ion current sensing for controlled auto ignition in internal combustion engines." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/8145.

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Envirom-nental pollution is a subject that needs urgent addressing. Since the internal combustion engine has its fair share of accountability on this, research on techniques for increasing engine efficiency and emissions is necessary. Controlled Auto Ignition is a promising combustion mode, which increases fuel efficiency while also reducing NOx emissions to negligible levels. This Thesis concentrates on the implementation of this mode through experimental research, on an engine equipped with a fully variable valvetrain. Investigation of the operational window, emissions, fuel consumption, thermodynamic efficiency is carried out and ways to improve on these are discussed. The governing consideration, however, is the control method for this rather intricate combustion mode. As such, experimental data acquisition and analysis of ion current under the whole operating spectrum, from spark ignition to full autoignition is made. It is found that the expected gains in fuel consumption and emissions are realized. In addition, ion current proves to be a very powerful and cost effective tool for engine monitoring, diagnosis and control. The author concludes that Controlled Auto Ignition is a viable proposition for mass production engine designs and that ion current, although not absolutely vital for engine control, considerably increases engine control thus allowing for greater operating window under autoignition, without compromising reliability or cost.
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Holub, Anna, and Jie Liu. "Recognizing Combustion Variability for Control of Gasoline Engine Exhaust Gas Recirculation using Information from the Ion Current." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-235.

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The ion current measured from the spark plug in a spark ignited combustion engine is used

as basis for analysis and control of the combustion variability caused by exhaust gas

recirculation. Methods for extraction of in-cylinder pressure information from the ion

current are analyzed in terms of reliability and processing efficiency. A model for the

recognition of combustion variability using this information is selected and tested on both

simulated and car data.

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6

Ogunjobi, Taiwo A. "Computational Study of Ring-Cusp Magnet Configurations that Provide Maximum Electron Confinement." Wright State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=wright1166226698.

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7

Botha, Johannes Rudolf. "Design of an RF ion thruster." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86267.

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Thesis (MEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Recent years have seen a decline in the rate of space exploration due to the inefficiency of chemical rockets. Therefore alternative fuel efficient propulsion methods are being sought to enable cost effective deep space exploration. The high fuel efficiency of electric thrusters enable a spacecraft to travel further, faster and cheaper than any other propulsion technology available. Thus electric propulsion has become the propulsion of choice for scientists and engineers. A typically electric thruster contains some sort of electrode to ionise the propellant. Although this is feasible for short space missions, it becomes impractical for more ambitious space missions as electrodes erode over time. The alternative is to ionise the propellant using electromagnetic fields, which eliminates lifespan issues associated with electrode based thrusters. In order to examine methods of improving the lifespan and performance of electric thrusters, this thesis aimed to study the method of microwave discharge ionisation for an electric thruster. This includes the design of an RF Ion Thruster with extraction and acceleration grids to generate thrust. A 600 W 2.45 GHz magnetron (obtained from a conventional microwave oven), coupled to circular TM010 resonant cavity, was used to ionise neutral argon gas. The process of electron cyclotron resonance (ECR) was used to ensure the efficient ionisation of a high density plasma. The thrust was achieved with a three-grid system biased at high voltages to accelerate positively charged argon ions to high exhaust velocities. Results yielded the success of the designed electromagnetic based thruster, measuring approximatively 1.78 mN of thrust with a specific impulse of Isp = 3786 seconds. The ECR process produced a high plasma density with a plasma absorption rate of approximately 77% of the total input microwave power. The final results obtained were found to match the predicted results extremely well and resembled results found in literature. This demonstrates the efficiency of the RF ion thruster that was designed in this project and the future use in space exploration activities. However, future research needs to be undertaken on a controlled feedback system that will ensure optimal operating conditions for maximum performance. In addition, the method of grid-less acceleration needs to be studied to achieve maximum thrust and specific impulse.
AFRIKAANSE OPSOMMING: In onlangse jare het ’n afname in die tempo van die verkenning van die ruimte dit te danke aan die ondoeltreffendheid van chemiese vuurpyle. Derhalwe moet alternatiewe brandstof aandrywing metodes ondersoek word, om koste-effektiewe diep ruimte-eksplorasie moontlik te maak. Die hoë brandstof-doeltreffendheid van elektriese ontbranders stel ’n ruimtetuig in staat om verder, vinniger en goedkoper te reis as enige ander aandrywing tegnologie wat tans beskikbaar is. Dus het elektriese aandrywing metodes die aandrywings keuse vir wetenskaplikes en ingenieurs geword. ’n Tipies elektriese vuurpyl/aandrywer bevat ’n vorm van elektrode om die brandstof (argon gas) te ioniseer. Alhoewel hierdie elektrode proses van ionisasie effektief is vir kort ruimte missies, word dit onprakties vir meer ambisieuse ruimte missies as gevolg van verweering van elektrodes met verloop van tyd. ’n Alternatief is om die dryfmiddel/brandstof te ioniseer deur gebruik te maak van elektromagnetiese velde. Die elekromagnetiese velde sal die lewensduur van die vuurpyl vermeerder deur die verweering van elektrodes, wat geassosieer word met tipiese elektrieses vuurpyle, te elimineer. Hierdie tesis se doelwit is om die metode van mikrogolf ontslag ionisasie vir ’n elektriese vuurpyl/aandrywer te bestudeer om ten einde die lewensduur en doeltreffendheid van elektriese vuurpyl/aandrywer te ondersoek. Dit sluit in die ontwerp van ’n radio frekewensie ioon vuurpyl/aandrywer met ’n ontginning en versnelling matriks/rooster om stukrag te genereer. ’n 2,45 GHz magnetron (verkry vanaf ’n konvensionele mikrogolfoond), gekoppel aan ’n TM010 resonante holte, was gebruik om neutrale argon gas te ioniseer. Die proses van elektron siklotron resonansie (ESR) was gebruik om die doeltreffende ionisasie van ’n hoë digtheid plasma te verseker. Die aandrywing/stukrag was behaal met ’n drie-matriks-stelsel, bevoordeel deur hoë spannings om die positief-gelaaide argon ione te versnel. Resultate opgelewer, het die sukses van die ontwerp van ’n elektromagnetiese gebaseerde vuurpyl/aandrywer met ’n benaderde meting van ongeveer 1.78 mN van stukrag/aandrywing met ’n spesifieke impuls van Isp = 3786 sekondes bewys. Die ECR proses het ’n hoë plasma digtheid geproduseer met ’n plasma opname persentasie van ongeveer 77% van die totale inset mikrogolf energie. Die finale uitslae wat verkry was, het bevind dat die voorspelde resultate baie goed inpas met resultate in beskikbare literatuur. Dit dui op die doeltreffendheid van die RF ioon vuurpyl/aandrywer wat ontwerp is in hierdie projek vir die toekomstige gebruik in ruimte eksplorasie-aktiwiteite. Toekomstige navorsing moet op ’n beheerde terugvoer sisteem onderneem word, wat optimale werktoestande verseker vir maksimum prestasie. Daarbenewens moet die metode van matriks-lose versnelling bestudeer word, om maksimum versnelling/stukrag en spesifieke impuls te verseker.
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8

Rodrigues, Junior Robério. "Avaliação comparativa de recobrimentos superficiais para tuchos de válvula através de ensaios de desgaste." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263572.

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Orientador: Cecília Amélia de Carvalho Zavaglia
Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-16T19:02:52Z (GMT). No. of bitstreams: 1 RodriguesJunior_Roberio_M.pdf: 3328140 bytes, checksum: d0f2014c71eeb448ae530ee5df6b8479 (MD5) Previous issue date: 2010
Resumo: Com o intuito de avaliar a eficiência de diferentes recobrimentos superficiais aplicados a tuchos de válvulas - um componente utilizado em motores à combustão - foram propostos alguns recobrimentos que foram comparados a um recobrimento já utilizado pela indústria. Para as avaliações foram realizados ensaios de microdureza, ensaios de desgaste micro-abrasivo e avaliações da microestrutura dos recobrimentos. Os recobrimentos estudados foram: nitretação a gás convencional, esta já utilizada pela indústria; implantação iônica por imersão em plasma (IIIP) de nitrogênio; IIIP de nitrogênio sobre a camada já existente de nitretação a gás convencional; e confrontada com uma amostra sem nenhuma camada de recobrimento superficial aplicada. Os ensaios de desgaste micro-abrasivo foram realizados em um equipamento do tipo esfera contra bloco, utilizando solução abrasiva de carboneto de silício (SiC), e variando a carga normal aplicada, sendo elas de 1, 2 e 3N. Os resultados mostram que a nitretação a gás convencional obteve o mais elevado nível de microdureza na superfície e também o mais elevado nível de desgaste por micro-abrasão; este resultado prevaleceu nesta amostra para todas as cargas normais aplicadas. Em geral, a amostra que obteve o melhor nível de desgaste, ou seja, o menor volume desgastado foi a amostra que não tinha nenhum tipo de recobrimento
Abstract: With the intention to evaluate the efficiency of different coatings applied to valve tappets - a component used in combustion engines - was proposed some coatings that was compared to an coating already known by the industry. For the evaluations were performed micro hardness tests, micro abrasive wear tests and studies of the microstructure of the coatings. The coatings studied were: conventional gas nitriding, this one already used by the industry; ionic implantation by plasma immersion (IIPI) of nitrogen; IIPI of nitrogen over the layer already existing of conventional gas nitriding; against a sample that was tested without any layer of coating. The micro abrasive tests were performed in an equipment named ball-on-block, using abrasive solution of silicon carbide (SiC), and varying the normal load from 1, 2 and 3N. The results showed that the conventional gas nitriding performed the highest level of micro hardness on the surface, and also the highest level of micro abrasion wear; this result prevailed in this sample in all the normal load applied. Generally, the sample that obtained the best level of wear, in other words, the lowest worn volume was the sample whithout any coating
Mestrado
Materiais
Mestre em Engenharia Automobilistica
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9

Benyo, Theresa L. "Analytical and Computational Investigations of a Magnetohydrodynamic (MHD) Energy-Bypass System for Supersonic Turbojet Engines to Enable Hypersonic Flight." Kent State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=kent1369153719.

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10

Gustafsson, Karin. "Ion Current Dependence on Operating Condition and Ethanol Ratio." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8053.

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This masters thesis investigates the possibility to estimate the ethanol content in the fuel using ion currents. Flexible fuel cars can be run on gasoline-ethanol blends with an ethanol content from0 to 85 percentage. It is important for the engine control system to have information about the fuel. In todays cars the measurements of the fuel blend are done by a sensor. If it is possible to do this with ion currents this can be used to detect if the sensor is broken, and then estimate the ethanol content until the sensor gets fixed. The benefit

of using ion currents is that the signal is measured directly from the spark plug and therefore no extra hardware is needed. To be able to see how the ethanol ratio affects the ion currents, the dependencies of the operating point have been investigated. This has been done by a literature review and by measurements in a Saab 9-3. Engine speed, load, ignition timing, lambda and spark plugs effects on the ion currents are especially studied. A black box model for the ion currents dependence on operating point is developed. This model describes the engine speed, load and ignition timing dependencies well, but it can not be used to estimate the ethanol ratio.

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11

Duchemin, Olivier B. Shepherd J. E. "An investigation of ion engine erosion by low energy sputtering /." Diss., Pasadena, Calif. : California Institute of Technology, 2001. http://resolver.caltech.edu/CaltechETD:etd-02242002-122344.

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12

Morris, Bradford Shepherd J. E. Shepherd J. E. "Charge-exchange collision dynamics and ion engine grid geometry optimization /." Diss., Pasadena, Calif. : California Institute of Technology, 2007. http://resolver.caltech.edu/CaltechETD:etd-02282007-154751.

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13

Tsay, Michael Meng-Tsuan. "Two-dimensional numerical modeling of Radio-Frequency ion engine discharge." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62713.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 106-109).
Small satellites are gaining popularity in the space industry and reduction in spacecraft size requires scaling down its propulsion system. Low-power electric propulsion poses a unique challenge due to various scaling penalties. Of high-performance plasma thrusters, the radio-frequency ion engine is most likely to succeed in scaling as it does not require an externally applied magnetic field and is structurally simple to construct. As part of a design package an original two-dimensional simulation code for radio-frequency ion engine discharge is developed. The code models the inductive plasma with fluid assumption and resolves the electromagnetic wave in the time domain. Major physical effects considered include magnetic field diffusion and coupling, plasma current induction and ambipolar plasma diffusion. The discharge simulation is benchmarked with data from an experimental thruster. It shows excellent performance in predicting the load power and the internal power loss of the plasma. Predictability of anode current depends on the operating power but is generally adequate. Optimum skin depth on the order of half of chamber radius is suggested by the simulation. The code also demonstrates excellent scaling ability as it successfully predicts the performance of a smaller thruster with errors less than 10%. Using the code a brief optimization study was conducted and the results suggest the maximum thrust efficiency does not necessarily occur at the same frequency that maximizes the power coupling efficiency of the matching circuit.
by Michael Meng-Tsuan Tsay.
Ph.D.
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14

Mahalingam, Sudhakar. "Particle Based Plasma Simulation for an Ion Engine Discharge Chamber." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1198181910.

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15

Williams, Logan Todd. "Ion acceleration mechanisms of helicon thrusters." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47691.

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A helicon plasma source is a device that can efficiently ionize a gas to create high density, low temperature plasma. There is growing interest in utilizing a helicon plasma source in propulsive applications, but it is not yet known if the helicon plasma source is able to function as both an ion source and ion accelerator, or whether an additional ion acceleration stage is required. In order to evaluate the capability of the helicon source to accelerate ions, the acceleration and ionization processes must be decoupled and examined individually. To accomplish this, a case study of two helicon thruster configurations is conducted. The first is an electrodeless design that consists of the helicon plasma source alone, and the second is a helicon ion engine that combines the helicon plasma source with electrostatic grids used in ion engines. The gridded configuration separates the ionization and ion acceleration mechanisms and allows for individual evaluation not only of ion acceleration, but also of the components of total power expenditure and the ion production cost. In this study, both thruster configurations are fabricated and experimentally characterized. The metrics used to evaluate ion acceleration are ion energy, ion beam current, and the plume divergence half-angle, as these capture the magnitude of ion acceleration and the bulk trajectory of the accelerated ions. The electrode-less thruster is further studied by measuring the plasma potential, ion number density, and electron temperature inside the discharge chamber and in the plume up to 60 cm downstream and 45 cm radially outward. The two configurations are tested across several operating parameter ranges: 343-600 W RF power, 50-450 G magnetic field strength, 1.0-4.5 mg/s argon flow rate, and the gridded configuration is tested over a 100-600 V discharge voltage range. Both configurations have thrust and efficiency below that of contemporary thrusters of similar power, but are distinct in terms of ion acceleration capability. The gridded configuration produces a 65-120 mA ion beam with energies in the hundreds of volts that is relatively collimated. The operating conditions also demonstrate clear control over the performance metrics. In contrast, the electrodeless configuration generally produces a beam current less than 20 mA at energies between 20-40 V in a very divergent plume. The ion energy is set by the change in plasma potential from inside the device to the plume. The divergence ion trajectories are caused by regions of high plasma potential that create radial electric fields.. Furthermore, the operating conditions have limited control of the resulting performance metrics. The estimated ion production cost of the helicon ranged between 132-212 eV/ion for argon, the lower bound of which is comparable to the 157 eV/ion in contemporary DC discharges. The primary power expenditures are due to ion loss to the walls and high electron temperature leading to energy loss at the plasma sheaths. The conclusion from this work is that the helicon plasma source is unsuitable as a single-stage thruster system. However, it is an efficient ion source and, if paired with an additional ion acceleration stage, can be integrated into an effective propulsion system.
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Manzoor, Ahmad Mubashir. "Integration of JasperReports Server Engine in iCON Telematics Application." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-307157.

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Leica Geosystems Technology AB is a Sweden-based company (part of Hexagon Group) that designs and manufactures software and hardware for building surveying and machine control applications. Modern machine control applications are important for today's construction market as they help in improving accuracy, reliability and performance thereby helping construction companies complete the work in time and cutting down on extra costs. One of Leica Geosystems Technology's software products is a web-based solution for fleet management and production control called iCON Telematics. Using iCON Telematics, the users can manage their vehicles in real time and monitor their activity live and offline using Google Maps. iCON Telematics has three main features: Sync, View and Track. Using the Track feature, the users can generate critical reports on demand (via browser or email) or on scheduled basis via email. The current reporting engine was developed in-house some years ago that is difficult to maintain and lacks numerous features that other reporting engine provide with incredible ease. To overcome this problem, it was decided that a standalone reporting service, such as JasperReports Server should be used to replace the existing reporting engine. This will not only isolate the reporting engine from the main application but will also make it easier to maintain and use standard reporting features of JasperReports. The aim of this thesis work was to integrate JasperReports Server in the iCON Telematics application while replacing the in-house legacy reporting service. This task was successfully carried out and delivered. It is currently in use on the production server of iCON Telematics web application and is used by hundreds of users all over the world.
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Molin, Johan. "Investigation of Correlations Between COV of Ion Integral and COV of IMEP in a Port-Injected Natural-Gas Engine." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15949.

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Correlations between the coefficient of variations (COV) of ion current integrals and COV of indicated mean effective pressure (IMEP) are investigated. The investigations are made to see if there is a possibility to use ion sense technique for closed loop combustion control to maximize Exhaust Gas Recirculation (EGR) level with remaining combustion stability. The engine studied in this thesis is a stoichiometric natural gas engine with a three way catalyst working with different EGR levels. One way to increase the efficiency in a stoichiometric natural gas engine is to maximize the EGR level [3]. With a higher EGR level it is possible to open the throttle even further with a result of lower pumping losses. Also temperature losses to chamber walls will be smaller with high EGR levels. A closed loop system controlling the EGR valve against COV of IMEP around 5 % is used for this engine. For COV of flame peak integral in range from 0 to 15-20% of COV of IMEP a linear correlation was found for lambda less than 1.3. For COV of two peaks integral a linear correlation was found for the entire measured range. This correlation may not be used for a robust EGR control system due to a small increase of COV of ion integral and due to a high variance in COV of ion integral. Correlations are discussed for different ion integrals with different air/fuels ratios and EGR levels. A control strategy is also presented.

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18

Correa, Chrys. "Combustion simulations in Diesel engines using reduced reaction mechanisms." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961521937.

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Lübbecke, Marco. "Engine scheduling by column generation." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962821152.

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Gohary, Mohamed Morsy Abdel Meguid Salama el. "Diesel engines and solar energy for electric and cooling applications." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973168242.

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21

Espinoza, Villegas Pablo Andrés. "A simulation engine for ion-lithium battery packs in electric vehicles based on energetic autonomy and remaining useful life criteria." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/144139.

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Magíster en Ciencias de la Ingeniería, Mención Eléctrica
Los últimos desarrollos en baterías de ión-litio han permitido una verdadera revolución en la industria automotriz. Los vehículos eléctricos representan una porción del mercado que aumenta año a año. Estos vehículos operan bajo condiciones variables, requiriendo de bancos de baterías para hacer frente a las respectivas demandas de torque y potencia. En este trabajo construimos un simulador que, dado el tamaño del banco, determina cuando una recarga (autonomía) o reemplazo del banco (vida útil remanente) son necesarios. Con este fin estudiamos los indicadores de Estado-de-Carga (SOC), y Estado-de-Salud (SOH), usando modelos en espacio de estados discreto. Las predicciones se basan en una caracterización probabilística de los perfiles de uso en un vehículo eléctrico, que a su vez son una función de entradas genéricas, e.g. el mapa de la misión, las características mecánicas del vehículo, perfiles de conducción y configuración del banco de baterías. En nuestro enfoque estocástico, el pronóstico para el SOC y SOH son generados en un esquema basado en filtro de partículas, con medidas de riesgo e intervalos de confianza obtenidos tanto para el fin-de- la-descarga (en cada ciclo) como para el fin-de-vida-útil (reemplazo). Estos esquemas se benefician de la incorporación de metamodelos para la resistencia óh- mica interna y la eficiencia de Coulomb del banco. El primero depende de la demanda de corriente y el SOC, mientras el segundo se basa en la magnitud de la corriente y la profundi- dad de cada descarga. Ambos metamodelos son incluidos dentro del esquema del SOC/SOH, i) efectivamente introduciendo nueva fenomenología en ellos, y ii) proveyendo de una conex- ión entre el SOC/SOH y el cómo cada descarga afecta el estado de salud del banco de baterías como un todo. También presentamos una metodología para experimentos de laboratorio que son capaces de determinar estas cantidades empíricamente en baterías de ión-litio. Consideramos efectos ignorados hasta ahora en este tipo de modelos empíricos, i.e. cómo las condiciones de operación en una descarga conciernen al pronóstico de la vida útil rema- nente, y cómo las dependencias de la impedancia interna afectan la autonomía del vehículo. Un sub-producto de este trabajo es el mejoramiento del rango de opciones, modularidad y velocidad de ejecución de algoritmos. Finalmente, establecemos aquí las bases para trabajo futuro en diseño óptimo de bancos de baterías en función de perfiles de uso particulares.
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Lima, Leonardo Lopes. "Identificação dos fenômenos de combustão e detonação em um motor ciclo Otto através da corrente iônica." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-01112016-090618/.

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As legislações com restrições nos níveis de emissões de poluentes e a grande concorrência entre as montadoras fomentaram o desenvolvimento de sistemas mais eficientes de gerenciamento de motores a combustão interna. Entretanto, a falta de sensores que identifiquem as propriedades da combustão, e que sejam economicamente viáveis, dificulta o desenvolvimento de novos sistemas. Visando suprir parte dessas limitações, este trabalho propõe o uso do sensor de corrente iônica com duas finalidades: identificação dos fenômenos de combustão e detonação. Para identificação da combustão, atualmente é utilizado o sensor de fase instalado no motor, o que encarece o sistema de gerenciamento. Uma alternativa a este sensor seria utilizar a vela de ignição, já instalada dentro do cilindro do motor, como sensor de ionização da mistura ar/combustível durante a queima. Comparando a área sob a curva do sinal da corrente iônica durante a combustão com a área sob a curva durante a admissão, foi possível verificar que é viável a utilização do sinal da corrente iônica para substituição de uma funcionalidade do sensor de fase. Quanto à identificação do fenômeno da detonação, foi mostrado que o uso do sensor de corrente iônica possibilita a remoção do sensor de detonação. Para isso, foi realizada a correlação entre a energia de uma faixa de frequências dos harmônicos do sinal da corrente iônica com a energia do sinal proveniente do sensor de detonação. Dessa forma, este trabalho mostrou que é possível usar somente as velas de ignição, já presentes no veículo, como sensores. Além disso, os resultados positivos obtidos propiciam oportunidades para novas aplicações e novas pesquisas.
The laws that restrict pollutant emission levels and the competition among manufacturers fostered the development of more efficient internal combustion engine management systems. However, the lack of sensors to identify the properties of combustion, and which are economically viable, hinders the development of new systems. In order to address such limitations, this investigation proposes using the ionic current sensor with two purposes: identification of combustion and knock phenomena. The combustion identification is currently identified by the camshaft position sensor installed in the motor, which becomes more expensive for the management system. An alternative is using the spark plug, already installed inside the engine cylinder, such as ionization sensor of air/fuel mixture during combustion. Comparing the area under the curve of the ion current signal during combustion to the area under the curve during admission, it was found that it is feasible the use of ionic current signal to replace one feature of the camshaft position sensor. Concerning the identification of the knock phenomenon, it was shown that the use of the ionic current sensor allows the removal of the knock sensor. For this, the correlation between the energy signal in a frequency range of the ionic current harmonic with the energy of the signal from the knock sensor was performed Therefore, the use of spark plugs as sensors is very promising, in replacement to two existing sensors. Moreover, the positive results provide opportunities for new applications and researches.
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Mahmood, Zulshan. "An experimental investigation of flow processes in dual-intake valve engines." Thesis, King's College London (University of London), 1998. https://kclpure.kcl.ac.uk/portal/en/theses/an-experimental-investigation-of-flow-processes-in-dualintake-valve-engines(18d3d406-ddb3-4794-a976-9cbc37a220c3).html.

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24

Leoni, Luca. "Utilizzo di Google Kubernetes Engine per un'applicazione IoT di gestione dell'acqua in agricoltura." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21008/.

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Questa tesi ha come obiettivo quello di studiare l’ambiente Kubernetes e di importare l’applicazione sviluppata per il progetto SWAMP su Google Kubernetes Engine (GKE). SWAMP (Smart Water Management Platform) è un progetto Europeo H2020 che ha come obiettivo quello di realizzare una piattaforma per la gestione dell’acqua in agricoltura, con lo scopo primario di ridurne al minimo il consumo. Essa si basa su IoT, cioè “Internet of Things”, ed altre tecnologie avanzate come sensori e droni. Kubernetes è una piattaforma open source che permette di orchestrare tra loro applicazioni containerizzate, le quali hanno il vantaggio di essere facili da utilizzare e distribuire. Per creare i container contenenti le varie parti dell’applicazione complessiva si è utilizzata la tecnologia Docker. Come primo approccio si è studiato Kubernetes su di un sistema di prova, il quale contiene il database a grafo Virtuoso e il motore SEPA (alla base anche di SWAMP). In seguito si è testato il sistema di prova su Google Kubernetes Engine cercando di capire il suo funzionamento, con le relative similitudini a Kubernetes. Come ultimo passaggio è stata importata l’applicazione SWAMP su GKE. Per il corretto funzionamento dell’applicazione in GKE sono stati studiati anche una serie di concetti utili al corretto funzionamento dell’intera applicazione quali: volumi persistenti ed esposizione di servizi in rete.
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Rundin, Patrick. "Evaluation of a statistical method to use prior information in the estimation of combustion parameters." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6255.

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Ion current sensing, where information about the combustion process in an SI-engine is gained by applying a voltage over the spark gap, is currently used to detect and avoid knock and misfire. Several researchers have pointed out that information on peak pressure location and air/fuel ratio can be gained from the ion current and have suggested several ways to estimate these parameters.

Here a simplified Bayesian approach was taken to construct a lowpass-like filter or estimator that makes use of prior information to improve estimates in crucial areas. The algorithm is computationally light and could, if successful, improve estimates enough for production use.

The filter was implemented in several variants and evaluated in a number of simulated cases. It was found that the proposed filter requires a number of trade-offs between variance, bias, tracking speed and accuracy that are difficult to balance. For satisfactory estimates and trade-off balance the prior information must be more accurate than was available.

It was also found that similar a task, constructing a general Bayesian estimator, has already been tackled in the area of particle filtering and that there are promising and unexplored possibilities there. However, particle filters require computational power that will not be available to production engines for some years.


Vid jonströmsmätning utvinns information om förbränningsprocessen i en bensinmotor genom att en spänning läggs över gnistgapet och den resulterande strömmen mäts. Jonströmsmätning används idag för knack- och feltändningsdetektion. Flera forskare har påpekat att det finns än mer information i jonströmmen, bl.a. om bränsleblandningen och cylindertrycket och har även föreslagit metoder för att utvinna och använda den informationen för skattning av dessa parametrar.

Här presenteras en förenklad Bayesisk metod i form av en lågpassfilter-liknande skattare som använder förkunskap till att förbättra estimat på relevanta områden. Algoritmen är beräkningsmässigt lätt och kan, om den är framgångsrik, leverera skattningar av förbränningsparametrar som är tillräckligt bra för att användas för sluten styrning av en bensinmotor.

Skattaren, eller filtret, implementerades i flera varianter och utvärderades i ett antal simulerade fall. Resultaten visade på att flera svåra avvägningar måste göras mellan förbättring i varians, avvikelse och följning eftersom förbättring i den ena ledde till försämring i de andra. För att göra dessa avvägningar och få goda skattningar krävs bättre förhandskunskap och mätdata än vad som var tillgängligt.

Bayesisk skattning är ett stort befintligt område inom statistik och signalbehandling och den mest generella skattaren är partikelfiltret som har många intressanta tillämpningar och möjligheter. De har hittills inte använts inom skattning av förbränningsparametrar och har således go potential för framtida utveckling. De är dock beräkningsmässigt tunga och kräver beräkningsresurser utöver vad som är tillgängliga i ett motorstyrsystem idag.

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Penkal, Bryan James. "Steps in the Development of a Full Particle-in-Cell, Monte Carlo Simulation of the Plasma in the Discharge Chamber of an Ion Engine." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1367586856.

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27

Cong, Phan Chinh. "An approach to adaptive inference engine for rule-based consultation systems." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982121717.

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28

Renaud, Denis. "Caractérisation du propulseur PEGASES : diagnostics du filtre magnétique et du faisceau : optimisation de la géométrie." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2018/document.

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Le propulseur de PEGASES est un moteur ionique qui diffère des autres technologies. La particularité de ce propulseur est l’utilisation d’un gaz électronégatif, à savoir le SF₆. Un champ magnétique est utilisé pour piéger les électrons et augmenter la production des ions négatifs. Le plasma résiduel à faible densité d’électrons, dit plasma ion-ion, permet l’extraction et l’accélération des ions positifs et négatifs. Les ions recombinent par paire dans le faisceau et garantissent la neutralité dans le faisceau. L’extraction d’une quantité équivalente d’ions positifs et négatifs permet ainsi d’éviter l’emploi d’un neutraliseur. Afin d’étudier les propriétés du faisceau ionique, une sonde EXB est utilisée pour diagnostiquer les vitesses et les proportions des molécules formées puis accélérées. La sonde n’étant pas parfaite, une calibration permet de déterminer avec précision les différentes espèces présentes dans le plasma. La présence d’ions positifs et négatifs ont pu être démontré via des mesures par sonde EXB. La technique de photo-détachement par laser est employée afin d’étudier les ions de charge négative. Cette méthode permet d’obtenir la proportion d’ions négatifs par rapport aux électrons. L’électronégativité dans ce type de décharge est très importante. La technique a montré l’importance du filtre magnétique. Cependant, la configuration de celui-ci n’est pas optimale puisqu’une structure est créée par la dérive électronique. Un nouveau propulseur à géométrie circulaire a été conçu, construit et testé. Cette nouvelle architecture utilise une dérive électronique fermée circulaire grâce à des aimants permanents. Les expériences ont validé le concept et montre l’importance d’une géométrie en anneau
The PEGASES ion thruster differs from standard electric propulsion technologies through its use of electronegative gases, such as SF₆, as a propellant. Its operation relies on the trapping of electrons using a magnetic field and the creation of a plasma dominated by positive and negative ions. These ions are alternately accelerated to produce thrust, and later undergo a recombination to ensure beam neutrality. This thruster eliminates the need for an electron-producing neutralizer, which is a standard feature in other sources such as the Hall thruster. This thesis is divided into three parts. The first describes the development and implementation of a new EXB probe for the study of the ion beam properties, the identification of the beam chemical composition and the verification of the presence of negative and positive ion species. The second part concerns the design and application of a new laser photodetachment diagnostic for the measurement of the negative ion fraction. Lastly, a new ion-ion thruster with a circular geometry, known as AIPE, has been designed, constructed and successfully tested. This prototype eliminates the plasma asymmetry present in PEGASES and reveals the importance of the magnetic filter to source operation
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Quarantini, Enrico. "Progettazione e sviluppo di video-giochi per Smart-Phone: un caso di Studio su iPhone." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3521/.

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30

Karagiannopoulos, Solon. "In-cylinder species imaging in internal combustion engines using absorption spectroscopy." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/incylinder-species-imaging-in-internal-combustion-engines-using-absorption-spectroscopy(ec710f4d-df5d-481e-a864-73b9be1f1c6a).html.

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Combustion diagnostics based on Diode Lasers have been in focus of research in recent years, due to the advances in optical technologies. Tunable Diode Laser Absorption Spectroscopy (TDLAS) has been employed for in-cylinder, nonintrusive, crank-angle resolved measurements in Internal Combustion (IC) engines. This thesis addresses a novel opto-electronic, multi-wavelength scheme for line-ofsight gas absorption measurements and tomographic imaging in IC engines. High temporal resolution measurements of H2O vapour using direct absorption spectroscopy (DAS), with external intensity modulation for phase sensitive detection, is implemented with Semiconductor Optical Amplifiers (SOAs). Using spectroscopic databases, two Near-IR overtone water transitions have been appropriately selected for ratiometric temperature compensation to enable concentration measurements, and an additional wavelength to account for nonabsorbing attenuation. A scanned-wavelength approach was used for laboratory evaluation of the new technique at 250 KS/s, and comparison with simulated absorption lines showed excellent accuracy and precision. Fixed-wavelength, Time-Division-Multiplexing (TDM) operation with SOAs as optical switching elements has also been demonstrated in the laboratory. A preliminary demonstration of the scheme on an optical engine has been presented with three projections continuously monitored at 150 KS/s during motored and fired engine operation. Valuable data for the system characterisation and future modifications and improvement have been obtained. Finally, tomographic imaging results of liquid and vapour phase fuel distribution in a motored IC engine are also presented.
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31

Khalid, Ashiq Hussain. "Development of phosphor thermometry systems for use in development gas turbine engines." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/development-of-phosphor-thermometry-systems-for-use-in-development-gas-turbine-engines(f01316f9-4622-4a6d-b2d0-611a9191b5eb).html.

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The pursuit for improved engine efficiency is driving the demand for accurate temperature measurement inside turbine engines. Accurate measurement can allow engines to be operated closer to their design limits to improve thermal efficiency. It can enable engineers to verify mechanical integrity, provide better prediction of component life, validate CFD and other design tools and aid the development for leaner more efficient engines. Unfortunately, experimentally measuring surface temperatures under harsh rotating conditions is challenging. This EngD study conducted by Ashiq Hussain Khalid at the University of Manchester and Rolls-Royce plc, reviews the rationale of using phosphor thermometry over existing methods, including thermocouples, pyrometry and thermal paints/melts, which lack detail, accuracy, or are too expensive for continuous testing. Although phosphor thermometry exhibits desirable characteristics, the high temperature and fast rotating engine environment presents some challenges that would need to be addressed before a successful measurement system can be implemented. Examples of such issues include: rising blackbody radiation, restricted optical access, fibre optic constraints and limited time period to collect data. These factors will impose measurement limits and greatly influence the design philosophy of the system, including phosphor choice, phosphor lifetime characteristics, bonding technique, excitation/detection methodologies and probe design. Taking these into consideration, the research focuses on the development of phosphor thermometry systems for use in development gas turbine engines, with measurement solutions for specific engine components. The high pressure turbine blade was given research priority. A number of phosphors including YAG:Tb, YAG:Tm. Y2O3:Eu and Mg3F2GeO4:Mn were investigated and characterised in terms of intensity and lifetime decay, with increasing temperature up to 1500oC. Spectral analysis and absolute intensity measurements established emission peaks and permitted comparative quantitative analysis to optimise system setup. The intensity of phosphor emission relative to Planck's blackbody radiation was also performed. YAG:Tm under 355nm illumination was found to exhibit the highest emission intensity at high temperatures, and because its spectral emission peak at 458nm was the lowest, its advantage in terms of blackbody radiation was further amplified. For rotating components, an upper temperature limit is reached based on the emission intensity at rising blackbody radiation levels and the system's ability to detect fast decays. A lower limit is reached based on the quenching temperature, probe design and rotational velocity. There are different methods to correct the distorted decay waveform as it traverses through the acceptance cone of the fibre. A phosphor selection criterion, taking into consideration these limitations, was successfully applied for various rotating engine components. The optical layout was setup and tested on stationary and rotating cases under laboratory conditions using similar design constraints, including fibre choice, maximum permissible lens size and target distances. A series of tests validated design methodologies and assumptions to enable testing on full scale rotating engine components. Mg3F2GeO4:Mn, using 355nm illumination, was found to be the most suitable phosphor for the HP drive cone. The estimated performance under the expected rotational speeds was found to be 624-812°C with a standard uncertainty of ±0.99%. YAG:Tm, illuminated with 355nm, was found to be the most promising phosphor for high pressure turbine blade measurements. The performance under the expected rotational speeds was found to be 1117-1375°C with a standard uncertainty of ±0.97%. This is better than other competing technologies that are currently available for temperature measurement of rotating turbine blades.
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Dathe, Hendrik. "Nanostructured sulfur traps for the protection of high performance NOx storage, reduction catalysts in low emission engine applications." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979066832.

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33

Chen, Dejin. "Untersuchungen zur Optimierung eines solaren Niedertemperatur-Stirlingmotors." Doctoral thesis, [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=974523542.

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34

Rolph, James. "Residual stress characterisation in forgings for aero-engine application." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/residual-stress-characterisation-in-forgings-for-aeroengine-application(f0963136-4919-48f9-91fe-34a752ff4666).html.

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Residual stresses are the stresses which are present within a component without any external load. They can be introduced through any number of manufacturing processes and in-service conditions, meaning that they are almost ubiquitous in engineering components. The characterisation of residual stress is an important field of research particularly in an engineering context since the effects of residual stress sum with the loads. As a result, the performance of a component can be greatly enhanced, or significantly reduced, by the presence of residual stress depending on the sign of the stress and the applied load. In this EngD thesis the focus has been on the development of residual stress through the manufacturing processes of aero-engine forgings, specifically the turbine disc. The forgings studied were sub-scale geometries of the disc, forged from the nickel-base superalloy RR1000. The overall aim of this work is to improve the understanding of the residual stress generation and relaxation through implementation of advanced experimental characterisation techniques, with a view to improving current stress predicting process modelling capabilities. With this in mind the work has focussed on the use of neutron diffraction and the contour method to characterise residual stress experimentally, while residual stress predictions have been made using finite element modelling. The findings of this research indicated that very large residual stresses were generated as a result of the quenching process, and that these stresses were then relaxed and redistributed by ageing heat treatments and material removal by machining. The results obtained through the two experimental techniques exhibited very strong agreement, indicated a robust experimental process. Comparisons to the finite element predictions highlighted some issues with the current model; in particular it was found that the simulation of quenching could be improved by better definition of the heat transfer at the surface. Furthermore, the level of stress relaxation during ageing was consistently over predicted in the model. This result is thought to be the result of an over-prediction of the level primary creep in the alloy. Subsequent studies will investigate this behaviour further using the newly developed in-situ heat treatment capabilities which have developed as part of this research.
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Abduljalil, Abdulrahman S. Ahmed. "Investigation of thermoacoustic processes in a travelling-wave looped-tube thermoacoustic engine." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-thermoacoustic-processes-in-a-travellingwave-loopedtube-thermoacoustic-engine(f46f9345-d1b5-40a4-8388-f884d7adb7bc).html.

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In thermoacoustic devices, thermal energy is directly converted to an acoustic wave (mechanical energy) or an acoustic input is converted into thermal energy. This is a result of heat interaction between a solid material and adjacent gas, within the so-called ‘‘thermal penetration depth” of the compressible oscillatory flow. Thermoacoustic technology is receiving growing interest in research for its many advantages, such as having no moving parts, being environmentally friendly and the possibility of using renewable energy for its operation (Adeff and Hofler, 2000). However, this technology is still at the development stage and needs more research to produce feasible and practical devices that are ready for domestic and industrial applications. A looped-tube travelling-wave thermoacoustic engine was designed using DELTAEC (Design Environment for Low-amplitude ThermoAcoustic Energy Conversion). The device was equipped with a ceramic regenerator, which is commonly used in catalytic converters for automotive applications, with square channels. The results of preliminary testing of the device were compared with theoretical values estimated from the numerical model. Very close agreement was observed at the qualitative level and reasonable agreement was observed at the quantitative level. After the validation stage, the device was equipped with three selected low-cost porous materials for performance testing and studies. In addition to the ceramic regenerator that was tested before, regenerators made from stainless steel scourers, stainless steel wool and wire mesh screens were tested. This last type is widely available and commonly used in this application. To facilitate meaningful comparison, the regenerators were made in two sets: one having a common hydraulic radius of 200 μm and the other of 120 μm. In total, six regenerators were successfully tested. Before the performance experiments, all of the regenerators were tested in a steady air flow rig that was built for this purpose, to estimate their relative pressure drop due to viscous dissipation. The relative performance of the regenerators was then investigated. The testing focused on the onset temperature difference, the maximum pressure amplitude generated and the acoustic power output as a function of mean pressure as it varied from 0 to 10 bar gauge pressure. This comparative testing revealed a poor relative performance for the regenerators made of scourers and steel wool, while the cellular ceramic regenerator- 10 -seems to offer an alternative for traditional regenerator materials, which may reduce the overall system cost. The literature reports many different observations of nonlinear phenomena by various researchers, a fact which drove the candidate to carefully monitor the behaviour of the device at all stages and led to an interesting finding of a number of nonlinear behaviours during the start-up of the device. These behaviours included an “on-off” effect and “fishbone-like” oscillations in addition to the normal smooth start-up process. The new findings and the detailed observations are reported in chapter 6 of this thesis. The existence of these phenomena focused attention on identifying the key parameters affecting the existence and type of behaviour, which were found to be the mean pressure and the input power, in addition to the material of the regenerator. An attempt was also made to study the phenomena quantitatively. The observations suggest that there are strong interactions between the acoustic and temperature fields within the regenerator, which may be responsible for the reported quasi-periodic unsteady behaviour of the engine.
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Engin, İlhan [Verfasser], Markus [Akademischer Betreuer] Büscher, and Carsten [Akademischer Betreuer] Müller. "Towards Polarization Measurements of Laser-accelerated Helium-3 Ions / Ilhan Engin. Betreuer: Markus Büscher. Gutachter: Markus Büscher ; Carsten Müller." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1082033898/34.

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Engin, İlhan Verfasser], Markus [Akademischer Betreuer] Büscher, and Carsten [Akademischer Betreuer] [Müller. "Towards Polarization Measurements of Laser-accelerated Helium-3 Ions / Ilhan Engin. Betreuer: Markus Büscher. Gutachter: Markus Büscher ; Carsten Müller." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1082033898/34.

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38

Chohan, Sundas. "Evolving strategies to engineer tendon tissue in vitro." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/evolving-strategies-to-engineer-tendon-tissue-in-vitro(b1046d18-3e30-44bb-841e-a975a776cc5d).html.

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Tendons are able to undergo repeated cyclic loading in vivo without permanent deformation or mechanical failure. However, diseased, traumatised and decellularised tendons gradually lose the ability to resist load and fail because of creep deformation. The molecular basis of the mechanical properties of tendon and how cells establish and maintain these properties is poorly understood. New knowledge in this area is required to develop novel medical strategies to improve tendon repair and regeneration. Recent advances in tissue bioengineering have led to the formation of fibrin-based tendon-like tissue (‘tendon constructs’) that display the mechanical properties and ultrastructure of embryonic tendon. This thesis presents the characterisation of the tendon constructs derived from primary fibroblasts to understand the relationship between the cells and matrix during tissue development, and to establish the standard of in vitro engineered tendons. These findings facilitated protocol development to engineer human tendon-like tissue derived from stem cells. Novel findings of constructs formed from differentiated human pluripotent stem cells in feeder and feeder-free systems are presented. Fibrin gels were seeded with human dermal fibroblasts (HDF), chick tendon fibroblasts (CTF), MAN5 (Manchester, embryonic stem) cells, human embryonic stem cells (HuES7) and induced pluripotent stem cells (iPS). The gels were cultured until isometric tendon-like constructs were formed (T0) or continued for four or ten days post-formation. The mechanical properties, histology and gene expression of the constructs were analysed and compared between the constructs seeded with the aforementioned cell types. Varying the initial cell number (tested in CTF-seeded fibrin and collagen based constructs) significantly affected the final cell count and the mechanical properties of the constructs differentially at T0 and T10. A non-linear relationship exists between the initial and final cell number, and, between the initial cell number and mechanical properties. However, the results showed that cell number impacted cell-matrix stabilisation as strength per se was strongly dependent on initial cell number. Collagen-based constructs showed a significantly lower stiffness compared with fibrin-based constructs at T0 and T10. The stem cells and primary cells reproducibly underwent morphogenesis to form a 3D tissue similar to embryonic tendon in vivo expressing ECM markers such as collagens type I and III. The tissue also exhibited the ultrastructural characteristics and biomechanical profile of immature tendons. RNA seq and qPCR results demonstrated the upregulation of tendon-specific genes. Tendon-like tissue generated from human stem cells and HDFs in vitro has the potential to replace functional tissue lost through disease and to advance the understanding of the molecular basis of human tenogenesis.
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Katragkou, Eleni. "Aircraft based measurements of atmospheric sulfur dioxide and ground based measurements of gaseous sulfur (VI) in the simulated internal flow of an aircraft engine implications for atmospheric aerosol formation /." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969654588.

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40

Calverley, Dan. "Cumulative emissions reduction in the UK passenger car sector through near-term interventions in technology and use." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/cumulative-emissions-reduction-in-the-uk-passenger-car-sector-through-nearterm-interventions-in-technology-and-use(686e7c51-432b-4a0b-83f1-a1b127e1e5c3).html.

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Responsible for one in eight tonnes of national CO₂ emissions, the passenger car sector is pivotal to delivering on UK climate change commitments to avoiding warming of more than 2°C. This thesis provides a clear and quantitative framing of emissions reduction at the sectoral level, by disaggregating global cumulative emissions budgets and pathways associated with a range of probabilities of exceeding 2°C. The relatively low level of abatement currently planned for the UK car sector, it is argued, needs to be significantly increased for the following reasons: (i) a scientific basis in cumulative emissions for sectoral mitigation makes carbon budgets, rather than end point targets (e.g. 2050), of the first importance; (ii) the currently high probability (63%) of exceeding 2°C underpinning the current UK carbon budgets is inconsistent with the UK government’s commitment to avoiding ‘dangerous climate change’; (iii) short-term emissions growth in industrialising countries considerably reduces remaining emissions space for industrialised countries; (iv) very limited scope exists for any large sector to cut emissions by less than the national mean rate of decarbonisation at higher rates of mitigation (around 10% p.a. by the 2020s). The consequences for emissions space in other sectors if international aviation and shipping mitigate less than the mean are quantified. For UK car sector emissions to remain consistent with a low probability of exceeding 2°C while observing these limitations, this analysis finds that planned sectoral mitigation over the coming decade needs to be increased fourfold. Means to address this expected abatement shortfall using readily available technology are investigated using a fleet emissions model to compare the effect on cumulative emissions of changes in a range of fleet parameters (including mean new car bulk emissions factors, vehicle age-proportionate annual distance travelled, and rates of fleet growth and turnover). Pushing existing car technology to the limit of expected short term efficiency gains is found to be insufficient to deliver a pathway with better than 56% probability of exceeding 2°C. Without reduction in aggregate demand for vehicle kilometres in the short term, lower probabilities of 2°C are placed beyond reach. The possibility of rapid step changes in levels of per capita car use is explored in qualitative interviews using narrative storyline scenarios. A range of coercive and voluntary interventions is considered in relation to their potential to overcome the structural and behavioural constraints to rapid transformation of personal travel.
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Bashtova, Kateryna. "Modélisation et identification de paramètres pour les empreintes des faisceaux de haute énergie." Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR4112/document.

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Le progrès technologique nécessite des techniques de plus en plus sophistiquées et précises de traitement de matériaux. Nous étudions le traitement de matériaux par faisceaux de haute énergie : un jet d’eau abrasif, une sonde ionique focalisée, un laser. L’évolution de la surface du matériau sous l’action du faisceau de haute énergie est modélisée par une EDP. Cette équation contient l’ensemble des coefficients inconnus - les paramètres de calibration de mo- dèle. Les paramètres inconnus peuvent être calibrés par minimisation de la fonction coût, c’est-à-dire, la fonction qui décrit la différence entre le résultat de la modélisation et les données expérimentales. Comme la surface modélisée est une solution du problème d’EDP, cela rentre dans le cadre de l’optimisation sous contrainte d’EDP. L’identification a été rendue bien posée par la régularisation du type Tikhonov. Le gradient de la fonction coût a été obtenu en utilisant les deux méthodes : l’approche adjointe et la différen- ciation automatique. Une fois la fonction coût et son gradient obtenus, nous avons utilisé un minimiseur L-BFGS pour réaliser la minimisation.Le problème de la non-unicité de la solution a été résolu pour le problème de traitement par le jet d’eau abrasif. Des effets secondaires ne sont pas inclus dans le modèle. Leur impact sur le procédé de calibration a été évité. Ensuite, le procédé de calibration a été validé pour les données synthétiques et expérimentales. Enfin, nous avons proposé un critère pour distinguer facilement entre le régime thermique et non- thermique d’ablation par laser
The technological progress demands more and more sophisticated and precise techniques of the treatment of materials. We study the machining of the material with the high energy beams: the abrasive waterjet, the focused ion beam and the laser. Although the physics governing the energy beam interaction with material is very different for different application, we can use the same approach to the mathematical modeling of these processes.The evolution of the material surface under the energy beam impact is modeled by PDE equation. This equation contains a set of unknown parameters - the calibration parameters of the model. The unknown parameters can be identified by minimization of the cost function, i.e., function that describes the differ- ence between the result of modeling and the corresponding experimental data. As the modeled surface is a solution of the PDE problem, this minimization is an example of PDE-constrained optimization problem. The identification problem was regularized using Tikhonov regularization. The gradient of the cost function was obtained both by using the variational approach and by means of the automatic differentiation. Once the cost function and its gradient calculated, the minimization was performed using L-BFGS minimizer.For the abrasive waterjet application the problem of non-uniqueness of numerical solution is solved. The impact of the secondary effects non included into the model is avoided as well. The calibration procedure is validated on both synthetic and experimental data.For the laser application, we presented a simple criterion that allows to distinguish between the thermal and non-thermal laser ablation regimes
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42

Pecino, Rodriguez Jose Ignacio. "Portfolio of original compositions : dynamic audio composition via space and motion in virtual and augmented environments." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/portfolio-of-original-compositions-dynamic-audio-composition-via-space-and-motion-in-virtual-and-augmented-environments(637e9f5b-7d42-4214-92c4-70bac912cec2).html.

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Electroacoustic music is often regarded as not being sufficiently accessible to the general public because of its sound-based abstract quality and the complexity of its language. Live electronic music introduces the figure of the performer as a gestural bodily agent that re-enables our multimodal perception of sound and seems to alleviate the accessibility dilemma. However, live electronic music generally lacks the level of detail found in studio-based fixed media works, and it can hardly be transferred outside the concert hall situation (e.g. as a video recording) without losing most of its fresh, dynamic and unpredictable nature. Recent developments in 3D simulation environments and game audio technologies suggest that alternative approaches to music composition and distribution are possible, presenting an opportunity to address some of these issues. In particular, this Portfolio of Compositions proposes the use of real and virtual space as a new medium for the creation and organisation of sound events via computer-simulated audio-sources. In such a context, the role of the performer is sometimes assumed by the listener itself, through the operation of an interactive-adaptive system, or it is otherwise replaced by a set of automated but flexible procedures. Although all of these works are sonic centric in nature, they often present a visual component that reinforces the multimodal perception of meaningful musical structures, either as real space locations for sonic navigation (locative audio), or live visualisations of physically-informed gestural agents in 3D virtual environments. Consequently, this thesis draws on general game-audio concepts and terminology, such as procedural sound, non-linearity, and generative music; but it also embraces game development tools (game engines) as a new methodological and technological approach to electroacoustic music composition. In such context, space and the real-time generation, control, and manipulation of assets combine to play an important role in broadening the routes of musical expression and the accessibility of the musical language. The portfolio consists of six original compositions. Three of these works–Swirls, Alice - Elegy to the Memory of an Unfortunate Lady, and Alcazabilla–are interactive in nature and they required the creation of custom software solutions (e.g. SonicMaps) in order to deal with open-form musical structures. The last three pieces–Singularity, Apollonian Gasket, and Boids–are based on fractal or emergent behaviour models and algorithms, and they propose a non-interactive linear organisation of sound materials via real-time manipulation of non-conventional 3D virtual instruments. These original instrumental models exhibit strong spatial and kinematic qualities with an abstract and minimal visual representation, resulting in an extremely efficient way to build spatialisation patterns, texture, and musical gesture, while preserving the sonic-centric essence of the pieces.
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43

Taylor-Goh, Sylvia Margaret Eileen Josephine. "Are there similarities and differences in the content and process of clinical decision making by Biomedical Engineers, Occupational Therapists and Speech and Language Therapists when assessing for electronic assistive technology for adults with an acquired brain injury?" Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/are-there-similarities-and-differences-in-the-content-and-process-of-clinical-decision-making-by-biomedical-engineers-occupational-therapists-and-speech-and-language-therapists-when-assessing-for-electronic-assistive-technology-for-adults-with-an-acquired-brain-injury(b7744cee-d63f-4178-a6e8-c8bb9a99c680).html.

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Electronic assistive technology (EAT) is prescribed by different professionals. Little is known regarding how these professionals make prescription decisions or their perceptions of their specialist knowledge and role in the assessment process. Study Aims: • to explore the participants’ perceptions of their specialist knowledge and role (Study 1); • to investigate the similarities and differences in the content and process of clinical decision making (CDM) during assessment and prescription of EAT for adults with an acquired brain injury (Study 2). Design: A cross-sectional design employing concurrent think-aloud method and semi-structured interviews. Methods: Two standardised case scenarios were presented to participants asked to think aloud their assessment of the patient (Study 2). A semi-structured interview followed (Study 1). Verbal data underwent thematic and analytic coding. The analytic coding underwent statistical analysis to explore the usage differences of the decision making processes between the professions. Decision process graphs (DPG) were drawn to explore whether there were patterns of use of the CDM processes according to level of expertise. Subjects: A purposive sample of 60 participants (BE, n=20; OT, n=20; SLT n=20) from assistive technology centres and brain injury units across England. Results: The CDM content was similar across the professions. The hypothetico-deductive model of decision making was used and two further stages, “cue implication” and “hypothesis implementation” emerged from the data. Patterns were observed in the DPG, which may be associated with differences in the CDM process according to levels of expertise. Participants’ reported profession-specific differences in their specialist knowledge and role, which were not clearly evident from the Study 2 results. Conclusions: The content and process of clinical decision making was similar across the three professions, though profession-specific specialist knowledge and role differences were reported by the participants. Level of expertise may affect the CDM process but did not affect the final prescription.
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Duchemin, Olivier Bernard. "An investigation of ion engine erosion by low energy sputtering." Thesis, 2001. https://thesis.library.caltech.edu/725/1/OBD_thesis.pdf.

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Unlike chemical propulsion systems, which are fundamentally limited in performance by propellant energy density, electric propulsion devices, such as ion engines, are limited in iotal deliverable impulse by maximum propellant throughput due to engine wear. In order to perform realistic modeling of engine lifetime, the erosion mechanisms involved must be understood. In particular, the damage---or sputtering---caused by slow ions on solid surfaces is extremely difficult to quantify. We first review the engine failure modes in which sputtering of molybdenum by slow xenon ions plays a critical role. We then present the relevant physical mechanisms, and describe a model for estimating the minimum kinetic energy necessary to dislodge a surface atom. Over seventeen analytical approaches to the energy dependence of sputtering have been published in the literature. We implement the four that are most relevant to ion engine erosion processes. In addition, we use the Monte-Carlo simulation program TRIM to calculate sputtering yields. We find, in particular, that the relative sensitivity of sputtering yield to surface binding energy increases dramatically near the sputtering threshold energy. Although the surface binding energy is a (weak) function of temperature, we show that the sputtering yield should not increase significantly at temperatures typical of ion engine operation. An experimental approach to the measurement of low energy sputtering yields is implemented and validated. Based on the Quartz Crystal Microbalance (QCM) technique, this method takes advantage of the differential mass sensitivity exhibited by the piezoelectric quartz resonator used in this study. Because of the importance of surface contamination in low energy sputtering, a surface kinetics model is presented to describe a surface under the simultaneous cleaning effect of ion bombardment, and background gas flow contamination. A special case of simultaneous surface contamination and erosion occurs during engine ground testing, where carbon is backsputtered on the accelerator grid from the facility. We describe experiments to measure ion-induced desorption cross-sections for carbon on molybdenum, before concluding that the protective effect of the carbon contamination is unlikely to significantly affect engine erosion, so that ground testing results are applicable to space operations
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Morris, Bradford S. "Charge-Exchange Collision Dynamics and Ion Engine Grid Geometry Optimization." Thesis, 2007. https://thesis.library.caltech.edu/807/1/thesis_main.pdf.

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The development of a new three-dimensional model for determining the absolute energy distribution of ions at points corresponding to spacecraft surfaces to the side of an ion engine is presented. The ions resulting from elastic collisions, both charge-exchange (CEX) and direct, between energetic primary ions and thermal neutral xenon atoms are accounted for. Highly resolved energy distributions of CEX ions are found by integration over contributions from all points in space within the main beam formed by the primary ions.

The sputtering rate due to impingement of these ions on a surface is calculated. The CEX ions that obtain significant energy (10 eV or more) in the collision are responsible for the majority of the sputtering, though this can depend on the specific material being sputtered. In the case of a molybdenum surface located 60 cm to the side of a 30 cm diameter grid, nearly 90% of the sputtering is due to the 5% of ions with the highest collision exit energies. Previous models that do not model collision energetics cannot predict this. The present results agree with other models and predict that the majority of the ion density is due to collisions where little to no energy is transferred.

The sputtering model is combined with a grid-structure model in an optimization procedure where the sputtering rate at specified locations is minimized by adjustment of parameters defining the physical shape of the engine grids. Constraints are imposed that require that the deflection of the grid under a specified load does not exceed a maximum value, in order to ensure survivability of the grids during launch. To faciliate faster execution of the calculations, simplifications based on the predicted behavior of the CEX ions are implemented. For diametrically opposed sputtering locations, a rounded barrel-vault shape reduces the expected sputtering rate by up to 30% in comparison to an NSTAR-shaped grid.

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Lee, Zhih-Young, and 李志洋. "Occupational Arsenic Exposure and Urinary Inorganic Arsenic Metabolites of Ion Implanter Maintenance Engineers." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/43586710765809092779.

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碩士
國立臺灣大學
職業醫學與工業衛生研究所
89
In the wafer fabrication facility of semiconductor industry, the routine maintenance of ion implanter potentially exposes the engineers to hazard when the maintenance engineers disassemble the ion implanter for different types of maintenance, especially arsenic or arsenic compounds in it. A previous study has shown that the urinary inorganic arsenic metabolites levels of maintenance engineers slightly increased during the ion implanter maintenance days. This study analyzed specific inorganic arsenic metabolites levels of the ion implanter maintenance engineers'' urine using HPLC-HG-AAS to study the potential arsenic exposure during a maintenance work. Totally, 30 subjects of exposure group and 12 subjects of control group from 6 wafer fabrication facilities subject were recruited in this study. First morning-voided urine of each was sampled for 7 consecutive days. Results show the levels of urinary inorganic arsenic metabolites for maintenance engineers group were 1.7±1.4 μg/L, 1.4±1.1 μg/L, 6.3±6.7 μg/L, 20.2±14.1 μg/L, 29.8±17.0 μg/L for As3+, As5+, monomethylarsonic acid, dimethylarsinic acid and total inorganic arsenic, respectively. Meanwhile, these arsenic of non-exposure group were 1.6±1.5 μg/L, 1.0±1.0 μg/L, 4.1±5.5 μg/L, 21.3±13.1 μg/L and 28.1±17.5 μg/L, respectively. After adjusted for the creatinine level, the total urinary inorganic arsenic metabolites levels were 21.5±10.0 μg/g creatinine, 24.7±12.3 μg/g creatinine for the maintenance engineers group and non-exposure group, respectively. It was also indicated that only a little difference of urinary inorganic arsenic metabolites level between maintenance engineers group and non-exposure group. It seemed like the arsenic exposure of the maintenance engineers was limited. But, continuous exposure control and motoring are still recommended to prevent the chronic adverse health effect after long-term occupational exposure. But, among 3 comparing groups, i.e. the maintenance engineers with maintenance work, the maintenance engineers without maintenance work and the non-exposure group, the proportions of monomethylarsonic acid 22.6±16.4 ％, 18.7±12.2 ％ and 13.9±9.5 ％, respectively, and that for dimethylarsinic acid 66.0±15.5 ％, 69.2±14.4 ％, and 76.6±10.0 ％, respectively shows a indicating a interesting reverse rends. Further study is warranted to explore the mechanism of this phenomenon. Besides, at low dose of occupational arsenic exposure, the sources of urinary inorganic arsenic metabolites need to be more clearly defined to exclude the confounding source from seafood.
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47

Beernaert, Leander Edward Bessa. "Cross platform 3D rendering engines and mobile devices/smartphones." Master's thesis, 2011. http://hdl.handle.net/1822/28067.

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Dissertação de mestrado em Engenharia Informática
Now more than ever, we live in a cross platform technological world. We are surrounded by various platforms, each with their own set of advantages and drawbacks. We’ve come to a point where we cannot delay the transition of software from one platform to another. This has become increasingly more visible with the "rise of the smartphones". Their evolution has sparked quite an interest and due to their ubiquitous nature and, CPU and GPU performance, they prove to be very interesting and useful computing devices. The aim of this dissertation is to port the 3D rendering engine, Curitiba, currently being developed on Windows, to the second and third most popular platforms: Mac OS X and iOS (iPhone and iPad), respectively, and create one unified project. Due to incompatibilities presented by the wxWidgets toolkit (2.8.x) on Mac OS X (10.6 and greater), we ported Curitiba to the GNU/Linux platform first since it’s also POSIX compliant. Sadly, the Android platform had to be left out because, at the time, it lacked the support for C++’s STL and Exceptions. Throughout this dissertation we shall cover all the challenges faced to transform Curitiba into a cross platform software and the development of the resulting unified project. Our secondary objective is to replace the traditional keyboard and mouse interactions in a 3D rendering engine by implementing new interaction models which make use of the touch screen and/or the sensors available on the iOS platform.
Agora mais que nunca, vivemos num mundo tecnológico multi-plataforma. Estamos rodeados de várias plataformas, cada uma com as suas vantagens e desvantagens. Chegamos a um ponto em que não pudemos adiar mais a transição do software de uma plataforma para outra. Isto tornou-se gradualmente mais visível com a ”ascensão dos smartphones”. A sua evolução tem despertado bastante interesse e graças à sua natureza ubíqua e, desempenho ao nível do CPU e GPU. Estes demonstram ser sistemas computacionais bastante interessantes e úteis. O objectivo desta dissertação é portar o motor de renderização 3D, Curitiba, desenvolvido no Departamento de Informática da Universidade do Minho, actualmente desenvolvido em Windows, para a segunda e terceira plataformas mais populares: Mac OS X e iOS (iPhone e iPad)2, respectivamente e criar um único projecto. Devido a uma incompatibilidade com a ferramenta wxWidgets [52] (2.8.x) em Mac OS X (10.6 e maior), portamos o Curitiba para GNU/Linux primeiro visto que também implementa as normas POSIX. Infelizmente, tivemos que abandonar a plataforma Android devido a este, na altura, não possuir suporte para o STL e Excepções do C++. Ao longo desta dissertação vamos abordar as dificuldades encontradas ao transformar o Curitiba num software cross plataforma e o desenvolvimento do projecto unificado. O nosso objectivo secundário consiste em substituir as interacções tradicionais com teclado e rato num motor de renderização 3D com novos modelos de interacção que tiram proveito do ecrã táctil e/ou sensores disponíveis na plataforma iOS.
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48

Chen, Li. "Integrated design and control optimization of hybrid electric marine propulsion systems based on battery performance degradation model." Thesis, 2019. http://hdl.handle.net/1828/11149.

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This dissertation focuses on the introduction and development of an integrated model-based design and optimization platform to solve the optimal design and optimal control, or hardware and software co-design, problem for hybrid electric propulsion systems. Specifically, the hybrid and plug-in hybrid electric powertrain systems with diesel and natural gas (NG) fueled compression ignition (CI) engines and large Li-ion battery energy storage system (ESS) for propelling a hybrid electric marine vessel are investigated. The combined design and control optimization of the hybrid propulsion system is formulated as a bi-level, nested optimization problem. The lower-level optimization applies dynamic programming (DP) to ensure optimal energy management for each feasible powertrain system design, and the upper-level global optimization aims at identifying the optimal sizes of key powertrain components for the powertrain system with optimized control. Recently, Li-ion batteries became a promising ESS technology for electrified transportation applications. However, these costly Li-ion battery ESSs contribute to a large portion of the powertrain electrification and hybridization costs and suffer a much shorter lifetime compared to other key powertrain components. Different battery performance modelling methods are reviewed to identify the appropriate degradation prediction approach. Using this approach and a large set of experimental data, the performance degradation and life prediction model of LiFePO4 type battery has been developed and validated. This model serves as the foundation for determining the optimal size of battery ESS and for optimal energy management in powertrain system control to achieve balanced reduction of fuel consumption and the extension of battery lifetime. In modelling and design of different hybrid electric marine propulsion systems, the life cycle cost (LCC) model of the cleaner, hybrid propulsion systems is introduced, considering the investment, replacement and operational costs of their major contributors. The costs of liquefied NG (LNG), diesel and electricity in the LCC model are collected from various sources, with a focus on present industrial price in British Columbia, Canada. The greenhouse gas (GHG) and criteria air pollutant (CAP) emissions from traditional diesel and cleaner NG-fueled engines with conventional and optimized hybrid electric powertrains are also evaluated. To solve the computational expensive nested optimization problem, a surrogate model-based (or metamodel-based) global optimization method is used. This advanced global optimization search algorithm uses the optimized Latin hypercube sampling (OLHS) to form the Kriging model and uses expected improvement (EI) online sampling criterion to refine the model to guide the search of global optimum through a much-reduced number of sample data points from the computationally intensive objective function. Solutions from the combined hybrid propulsion system design and control optimization are presented and discussed. This research has further improved the methodology of model-based design and optimization of hybrid electric marine propulsion systems to solve complicated co-design problems through more efficient approaches, and demonstrated the feasibility and benefits of the new methods through their applications to tugboat propulsion system design and control developments. The resulting hybrid propulsion system with NG engine and Li-ion battery ESS presents a more economical and environmentally friendly propulsion system design of the tugboat. This research has further improved the methodology of model-based design and optimization of hybrid electric marine propulsion systems to solve complicated co-design problems through more efficient approaches, and demonstrated the feasibility and benefits of the new methods through their applications to tugboat propulsion system design and control developments. Other main contributions include incorporating the battery performance degradation model to the powertrain size optimization and optimal energy management; performing a systematic design and optimization considering LCC of diesel and NG engines in the hybrid electric powertrains; and developing an effective method for the computational intensive powertrain co-design problem.
Graduate
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49

Campos, Bruno Miguel Alves de. "Cálculo a Brincar Desenvolvimento de um Jogo Sério para uma melhor compreensão Matemática." Master's thesis, 2018. http://hdl.handle.net/10362/56302.

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Nos dias de hoje têm-se identificado vários problemas na aprendizagem das crianças nas várias disciplinas, com especial enfoque na matemática. As cri-anças com mais problemas neste domínio têm um défice de aprendizagem rela-tivamente a outras crianças o que condiciona as suas escolhas de futuro, que ficam mais limitadas podendo resultar, em casos extremos, numa exclusão social. Esta problemática tem tido várias abordagens de solução, utilizando dife-rentes formas e metodologias, que podem envolver jogos tradicionais ou manu-ais escolares. Estes métodos disponíveis, pela sua limitação, não têm conseguido acompanhar o avanço tecnológico e os que tentaram evoluir tecnologicamente não conseguiram uma implementação viável nas salas de aula. Este trabalho de dissertação assenta na criação de um jogo digital, mais especificamente um jogo sério, na área da educação. Este jogo poderá ser apli-cado nas salas de aula como alternativa aos jogos tradicionais ainda em uso, bem como nos intervalos entre as aulas ou mesmo em casa.
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Smrž, Dominik. "Elektroforetické stanovení inhibitorů koroze v chladicích kapalinách." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-396754.

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A determination of corrosion inhibitors in engine coolants represent a difficult analytical problem due to their different physicochemical properties. Nowadays a lot of instrument methods are needed to determine them. The aim of this work was the development of methods for their determination using only one instrumentation. Capillary zone electrophoreses was chosen as a suitable technique. Three electrophoretic methods for three groups of corrosion inhibitors were developed. Firstly, method for determination of inorganic anions was developed in range from 5 to 50 ppm with limit of detection around 1 ppm. Background electrolyte contains sodium chromate, CTAB and CHES solution. Analytes were detected indirectly at 450 nm. Another method was for determination of organic acids anions. They were determined in range from 5 to 500 ppm. Limit of detection for each analyte was around 1 ppm. Measurement was made with PDC a CTAC water solution. Indirect detection was used for this determination at 350 nm. Last developed method can be use for determination of aryltrizoles in range from 5 to 500 ppm. Limit of detection was around 1 ppm. As a background electrolyte was used sodium tetraborate solution. The developed methods were validated and their suitability for determination of corrosion inhibitors in real...
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