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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Κατασκευή αυτόματου συστήματος φόρτισης μπαταριών με μικροϋπολογιστικό σύστημα ειδικού σκοπού

Λουριδάς, Κωνσταντίνος 17 July 2014 (has links)
Στην παρούσα διπλωματική εργασία γίνεται επισκόπηση των βασικών τεχνολογιών επαναφορτιζόμενων και μη μπαταριών και στη συνέχεια μέσω της τεχνολογίας ενσωματωμένων συστημάτων παρουσιάζεται η υλοποίηση με λογισμικό πάνω σε έναν μικροελεγκτή ARM7 της Analog Devices, ενός φορτιστή μπαταριών τύπου NiMH. / In the following diploma thesis appears an overview of basic technologies of the rechargeable and non rechargeable batteries and then through technology of embedded systems shows the implementation with software on a microcontroller ARM7 of Analog Devices, of a NiMH battery charger.
2

Nabíječ akumulátorů s mikrokontrolérem. / Accumulator Charger with Microcontroller

Losenický, Roman January 2011 (has links)
My master thesis is focused on intorducing, analysing and describing the microprocessor controlled charger. The thesis is firstly describing and analysing the topic of accumulator cell charging for common technologies. Than there is detailed description of specific accumulator cell types (NiMH, NiCd and Li-ion) which is the microprocessor controled charger intend for. The next part of this thesis is showing the proposal of the charger. There is the block diagram, charger detailed schematics based on this block diagram. There is also list of the possible useful componets neccessary for charger assembling. All this is used for the final proposal of the chager itself. The main scope of this thesis is than the charger's microcontroler firmware decribed at the end of this thesis. Finaly confirmation of the charger proper proposal and assembly is the battery charging with the given basic parameters.
3

Longitudinal examination of behavioral markers of positive valence systems and anhedonia

Jordan, Duncan 07 August 2020 (has links)
The National Institute of Mental Health (NIMH) has provided a framework for studying psychopathology known as the Research Domain Criteria (RDoC), which conceptualizes depression and other mental disorders on a continuum of levels of analysis, ranging from molecular dysfunction to impairment in cognitive systems indexed by behavioral paradigms. Within the RDoC, these units of analysis and their corresponding normal-to-abnormal functioning can be placed within six domains: (1) negative valence systems; (2) positive valence systems; (3) cognitive systems; (4) social processes; (5) arousal and regulatory systems; and (6) sensorimotor systems. Given the recent emphasis on identifying further mechanisms associated with positive valence systems dysfunction, the present study aimed to assess the relationship between various behavioral paradigms (indexing perception, attention, affective working memory updating, and effort expenditure) and various conceptualizations of anhedonia, a heterogeneous, transdiagnostic symptom implicated as a core component within this domain. Participants (N = 101) with a range of depressive symptoms were recruited for a longitudinal study and completed six weekly in-person sessions, as well as a follow-up session that occurred approximately six weeks after the last session. Findings suggest there were no robust associations between these behavioral paradigms and various self-report measures of anhedonia, contrasting with previous empirical findings. As such, future studies are warranted to continue assessing these possible mechanisms of positive valence systems disturbance.
4

Regulátor pro nabíjení NiMH akumulátorů z fotovoltaického panelu / Charger controller for solar panel based charging of NiMH batteries

Kašpárek, Martin January 2011 (has links)
The aim of this master's thesis is suggest and construct regulator for charge NiMH storage battery from photovoltaic (PV) panel. Function regulator is tracking maximum power point from PV panel (MPPT), control charge and evaluation full charge of battery.
5

Desenvolvimento de um m?todo para extra??o de lant?nio em lixiviados de baterias NiMH utilizando sistemas aquosos bif?sicos

Oliveira, Wbiratan Cesar Macedo de 18 March 2016 (has links)
Disponibiliza??o do conte?do parcial, conforme Termo de Autoriza??o no trabalho. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2016-12-21T19:05:57Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-01-31T14:19:01Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) / Made available in DSpace on 2017-01-31T14:19:01Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) wbiratan_cesar_macedo_oliveira_parcial.pdf: 128173 bytes, checksum: 9c9067430cf3b7ef9b7952182484b258 (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Neste trabalho foi estudado o comportamento de extra??o do lant?nio em sistemas aquosos bif?sicos (SAB) e foi desenvolvido um novo m?todo hidrometal?rgico ambientalmente seguro para a extra??o seletiva de La a partir de lixiviado de baterias NiMH. O comportamento de extra??o do La foi avaliado verificando a influ?ncia dos seguintes par?metros: presen?a e concentra??o de diversos agentes extratantes (Alaranjado de xilenol, 1-(2-piridilazo)-2-naftol, Ditizona, 8-hidroxiquinolina, e 1,10-fenantrolina); pH (3,00, 6,00 e 9,00); eletr?lito (Li2SO4, Na2SO4, MgSO4, Na2C4H4O6 e Na3C6H5O7 ) e pol?mero (L64 e PEO1500) formadores do sistema. A efici?ncia de recupera??o foi avaliada atrav?s da an?lise da porcentagem de extra??o (% E) e as melhores condi??es de extra??o do analito foram obtidas no SAB formado por PEO1500 + Li2SO4 + H2O, pH = 6,00; empregando o extratante 1,10-fenantrolina, atingindo um valor m?ximo de %E = 74,1 %. Na sequencia o m?todo foi aplicado a um lixiviado de bateria NiMH. Os terras raras foram precipitados mediante ajuste de pH (2,50) e posteriormente solubilizado em solu??o de H2SO4 0,1 M. Ap?s 3 etapas sucessivas de extra??o foram obtidos altos valores de fator de separa??o (S) entre o analito e os concomitantes met?licos (SLa,Co = 6.3 x 103, SLa,Ni= 2,55 x 104, SLa,Fe= 1,15 x 103 and SLa,Ce= 30,9). Al?m disso, foi realizado um ensaio de stripping no qual 88,5% de La, em uma ?nica etapa, foi redisponibilizado sob a forma i?nica na FI para uma poss?vel etapa posterior de eletrodeposi??o. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / In this work was investigated the extraction behavior of lanthanum in the aqueous two-phase system (ATPS) and new environmentally safe hydrometallurgical method was developed for the selective extraction of La from NiMH battery leachate. The extraction behavior of La was evaluated verifying the influence of the following parameters on the metals extraction: presence and concentration of the several extractants 1-(2-piridil-azo)-2-naphtol, dithizone, 8-hydroxyquinoline, 1-10 phenanthroline and xylenol oragne; pH (3.00, 6.00 and 9.0); ATPS-forming electrolyte ((Li2SO4, Na2SO4, MgSO4, Na2C4H4O6 e Na3C6H5O7); ATPS-forming polymer (L64 or PEO1500). The recovery efficiency was evaluated through analyzing the extraction percentage (%E) and the best conditions for analyte extraction were achieved for the PEO1500 + Li2SO4 ATPS, pH = 6.00, using 1-10 phenanthroline as extractant agente (%E = 74,1 %). In the following section, the method was applied to a real NiMH battery leachate. The rare earths were precipitated by pH adjustment (2.50), which was solubilized in 0,1 M H2SO4 solution. After 3 steps of successive extractions it was possible to obtain high separation factor (S) values between the analyte and mettalic concomitant (SLa,Co = 6.3 x 103, SLa,Ni = 2,55 x 104, SLa,Fe = 1,15 x 103 and SLa,Ce = 30,9). Moreover, a stripping assay was carried out and after one single step, 88.5% of lanthanum was available to a possible electro winning step.
6

Recyclage de métaux venant d'accumulateurs NiMH : développement d'extractions liquide-liquide sélectives à partir de liquides ioniques / Recycling of metals from NiMH batteries : development of liquid-liquid selective extractions based on ionic liquids

Gras, Matthieu 12 October 2018 (has links)
Les accumulateurs nickel-hydrure métallique (NiMH) dominent actuellement le marché du stockage de l’énergie pour les véhicules hybrides. On estime à 1 milliard, le nombre de batteries NiMH produites chaque année. En fin de vie, le taux de recyclage de ces déchets électroniques reste faible, bien que la technologie NiMH contienne des quantités importantes de métaux onéreux et stratégiques. Deux grandes familles d’éléments chimiques coexistent sous forme de composés intermétalliques dans l’électrode négative: les métaux de transitions (TM) (Ni, Co, Mn et Fe) ainsi que les terres rares (REE) (La, Ce, Nd et Pr). Parmi les TM, le cobalt présente une criticité accrue. En effet, les minerais issus de réserves naturelles ne permettront pas de couvrir la demande croissante en cobalt liés au développement des technologies émergentes. Les REE produits à plus de 97 % en Chine sont au cœur des préoccupations de l’Union Européenne qui depuis 2010 pointe du doigt des techniques d’extractions dévastatrices pour l’environnement. C’est dans le but de répondre aux problématiques économiques et environnementales que le projet a été construit en associant l’entreprise de recyclage de batteries Recupyl® au laboratoire académique LEPMI grâce au financement du Labex CEMAM. L’objectif de ce travail est de proposer un procédé avec un faible impact environnemental pour le recyclage des métaux à partir de véritables accumulateurs NiMH. Pour cela, le remplacement de solvants volatiles organiques par des liquides ioniques, plus respectueux des principes de la ‘chimie verte’ sera étudié. En s’appuyant sur des procédés innovants d’extraction liquide-liquide et de récupération des éléments par hydrométallurgie et par électrochimie nous proposons une voie de valorisation des métaux présents dans ces batteries. / Nickel-metal hydride (NiMH) batteries are currently dominating the market of energy storage in hybrid electric vehicles. 1 billion cells are estimated to be produced each year. In their end-of-life, these electronical wastes exhibit low recycling rates, despite the fact that NiMH batteries contain high amounts of valuable and strategic metals. Two main metal families coexist as an intermetallic compound in negative electrodes: transition metals (TM) (Ni, Co, Mn and Fe) and rare earth elements (REE) (La, Ce, Nd and Pr). Among TM, cobalt exhibits the highest criticality rate. Indeed, natural ores will not cover the increasing cobalt demand linked to emerging technologies. REE produced at more than 97 % in China are at the centre of European Union’s preoccupations. To tackle economic and environmental issues, this project, supported by the labex CEMAM is a partnership between the company Recupyl® and the academic laboratory LEPMI. It aims at investigating on low environmental impact routes for the recycling of metals present in real spent NiMH batteries. This requires the replacement of volatile organic compounds by ionic liquids, respecting the principles of ‘green chemistry’. Based on innovative extraction and recovery processes of elements by hydrometallurgy and electrochemistry, we propose a flowsheet for the valorisation of metals from those batteries.
7

Contribution à l'évaluation du vieillissement des batteries de puissance utilisées dans les véhicules hybrides selon leurs usages

Montaru, Maxime 06 July 2009 (has links) (PDF)
Face à la raréfaction du pétrole et aux contraintes environnementales fixées dans le cadre du protocole de Kyoto, le domaine des transports tend à évoluer vers des technologies moins consommatrices et moins émettrices de gaz à effet de serre. À ce jour, dans le domaine de l'automobile, une solution technologique fortement envisagée est l'hybridation électrique des véhicules. Le développement de ces véhicules reste néanmoins limité à cause de l'incertitude concernant la durée de vie des batteries. Cette étude porte sur la préparation de tests de vieillissement accélérés et s'articule autour de deux axes : l'évaluation des performances des batteries à un instant de vie donné et la détermination de profils de sollicitations représentatifs de l'usage réel à utiliser pour les tests de cyclage. L'étude se focalise sur deux des technologies les plus prometteuses pour les véhicules hybrides électriques, c.-a-d. le nickel métal hydrure (NiMH) et le Lithium-ion (Li-ion).
8

A User Programmable Battery Charging System

Amanor-Boadu, Judy M 03 October 2013 (has links)
Rechargeable batteries are found in almost every battery powered application. Be it portable, stationary or motive applications, these batteries go hand in hand with battery charging systems. With energy harvesting being targeted in this day and age, high energy density and longer lasting batteries with efficient charging systems are being developed by companies and original equipment manufacturers. Whatever the application may be, rechargeable batteries, which deliver power to a load or system, have to be replenished or recharged once their energy is depleted. Battery charging systems must perform this replenishment by using very fast and efficient methods to extend battery life and to increase periods between charges. In this regard, they have to be versatile, efficient and user programmable to increase their applications in numerous battery powered systems. This is to reduce the cost of using different battery chargers for different types of battery powered applications and also to provide the convenience of rare battery replacement and extend the periods between charges. This thesis proposes a user programmable charging system that can charge a Lithium ion battery from three different input sources, i.e. a wall outlet, a universal serial bus (USB) and an energy harvesting system. The proposed charging system consists of three main building blocks, i.e. a pulse charger, a step down DC to DC converter and a switching network system, to extend the number of applications it can be used for. The switching network system is to allow charging of a battery via an energy harvesting system, while the step down converter is used to provide an initial supply voltage to kick start the energy harvesting system. The pulse charger enables the battery to be charged from a wall outlet or a USB network. It can also be reconfigured to charge a Nickel Metal Hydride battery. The final design is implemented on an IBM 0.18µm process. Experimental results verify the concept of the proposed charging system. The pulse charger is able to be reconfigured as a trickle charger and a constant current charger to charge a Li-ion battery and a Nickel Metal Hydride battery, respectively. The step down converter has a maximum efficiency of 90% at an input voltage of 3V and the charging of the battery via an energy harvesting system is also verified.
9

Testování a nabíjení akumulátorových článků / Testing and charging of accumulator cells

Sršeň, Jan January 2009 (has links)
Direction of the master's thesis is design and construct electronic device for testing available accumulators. Than there are in detail subscribe some metods of charging cells and their right usage to select type of cells. Also eventually problems that can become if the choice is false. Next part contains description of principles as several type accumulator works and their loading characteristic witch are important know for choose the best testing way. The most important knowledge is detection of stop point charging when accumulators are charged and following charging can be dangerous. Because there are more methods to detect this point so in thesis are overwrite. The most important part is design of tester. That is mapped to more segments witch communicating together. Controller part of intelligent tester contains ATmega128 microcontroller so there is present a passage of program code. Last section of master's thesis describe a physical consruction and explain division for smaller parts and hole process of tester function.
10

Automatický nabíječ akumulátorů pro zdravotnické přístroje / Automatic battery charger for medical equipment

Talanda, Oldřich January 2010 (has links)
The goal of this thesis is describe properties accumulators used in medical industry and proposal automatic baterry charger for medical equipment. The first part of the master’s thesis describes the most commonly used types of electrochemical accumulator systems used in the medical industry. Further listed are the criteria for the identification of the accumulator charge status. The second part of the master’s thesis defines demands on automatic baterry charger and proposal factual network solution.

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