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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.
11

System analysis perspectives : lead-acid battery recycling in British Columbia, Canada

Alvares da Silva, Ana Carolina 05 1900 (has links)
This dissertation aims to use a system thinking approach to describe and evaluate the Lead-Acid Battery Recycling Program in British Columbia, compare it with other provincial regulated recycling programs and identify strategies on how it can be improved. The research is presented in the manuscript based format, comprised of four interrelated chapters. Following the introduction, chapter 2 describes a multiple regression analysis to assess how various factors identified by informed stakeholders have contributed to recycling rate in 14 transportation zones from 1995 to 2005. This study demonstrates that the existing recycling scheme ineffectively promotes recycling as it has achieved an average of 75% over the past 13 years with large fluctuations among transportation zones. The regression also shows that recycling rate of transportation zones are not highly influenced by LME lead prices and Transportation Incentive (which can be explained by the strong market power of the recycling plants responsible for setting up the price of scrap lead to which the collectors respond). Chapter 3 identifies key components that influence the performance of varied recycling systems based on a comparative analysis of provincial recycling systems informed by expert interviews. In chapter 4, comprehensive evaluation criteria for the lead-acid battery recycling program is developed based on objectives and performance measures elicited through an extensive stakeholder consultation process with various individuals and organizations. Fundamental objectives identified by stakeholders include: reduce environmental impacts, reduce occupational health impacts, reduce net costs, increase equity in resource consumption patterns and increase systematic learning. In chapter 5, we use multiple criteria decision analysis (MCDA) to design and assess effective recycling strategies to meet societal objectives previously identified in the chapter 4. Recycling strategies were compiled using the results of chapter 3. The results reveals that the optimal policy for the lead-acid battery recycling system combines a return to retailer program financed through an advanced disposal fee included in the battery price in combination with increased plant or recycling capacity domestically. This research also provides relevant contributions to the refining and application of value-focused thinking and decision analysis methodologies.
12

System analysis perspectives : lead-acid battery recycling in British Columbia, Canada

Alvares da Silva, Ana Carolina 05 1900 (has links)
This dissertation aims to use a system thinking approach to describe and evaluate the Lead-Acid Battery Recycling Program in British Columbia, compare it with other provincial regulated recycling programs and identify strategies on how it can be improved. The research is presented in the manuscript based format, comprised of four interrelated chapters. Following the introduction, chapter 2 describes a multiple regression analysis to assess how various factors identified by informed stakeholders have contributed to recycling rate in 14 transportation zones from 1995 to 2005. This study demonstrates that the existing recycling scheme ineffectively promotes recycling as it has achieved an average of 75% over the past 13 years with large fluctuations among transportation zones. The regression also shows that recycling rate of transportation zones are not highly influenced by LME lead prices and Transportation Incentive (which can be explained by the strong market power of the recycling plants responsible for setting up the price of scrap lead to which the collectors respond). Chapter 3 identifies key components that influence the performance of varied recycling systems based on a comparative analysis of provincial recycling systems informed by expert interviews. In chapter 4, comprehensive evaluation criteria for the lead-acid battery recycling program is developed based on objectives and performance measures elicited through an extensive stakeholder consultation process with various individuals and organizations. Fundamental objectives identified by stakeholders include: reduce environmental impacts, reduce occupational health impacts, reduce net costs, increase equity in resource consumption patterns and increase systematic learning. In chapter 5, we use multiple criteria decision analysis (MCDA) to design and assess effective recycling strategies to meet societal objectives previously identified in the chapter 4. Recycling strategies were compiled using the results of chapter 3. The results reveals that the optimal policy for the lead-acid battery recycling system combines a return to retailer program financed through an advanced disposal fee included in the battery price in combination with increased plant or recycling capacity domestically. This research also provides relevant contributions to the refining and application of value-focused thinking and decision analysis methodologies.
13

Analysis and cost optimization of a USCG remote hybrid power system /

Weiss, Zachary A. January 2002 (has links) (PDF)
Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2002. / Thesis advisor(s): John Ciezki, Sherif Michael. Includes bibliographical references (p. 101-102). Also available online.
14

The evaluation of potential improvements of barton pot oxides for lead acid batteries

Geyer, Laurence Thomas January 2003 (has links)
Lead Oxide (PbO) is the main material used for the preparation of the active material for the positive and negative electrodes in the lead acid battery where the electrochemical reaction that provides the electrical energy of the battery takes place. The particle size distribution and surface area characteristics of the lead oxide play a major role in the electrical performance of the completed battery. The two most commonly used processes to manufacture PbO in the lead acid battery industry are the Barton pot and the Ball mill processes. These two processes produce oxides that differ in particle size distribution, particle shape and surface area. It is generally accepted that the Ball mill process produces an oxide with a smaller mean particle size with a higher surface area and better initial electrical performance than the Barton pot process to the detriment of an initial higher capital and running cost. The study showed that it is possible to improve the surface area and particle size distribution characteristics of Barton pot oxide, by subsequently hammer milling the oxide particles before the paste manufacturing process. The results showed that there was an initial reduction in the particle size with an increase in the surface area. This increased the electrochemical performance in terms of the high rate discharge. However, further hammering of the oxide reduced the average particle size only slightly with little change in the surface area and a reduction in the electrochemical performance. The study showed that an improvement in Barton pot oxide can be achieved with a hammering of the oxide in order to obtain a uniform particle size with improved surface area and an improved high rate performance of the electrochemical cells made with such an oxide. As a comparison, the particle size and surface area characteristics of Ball mill lead oxide subjected to the hammer milling process was also studied. The results showed a similar effect to the Barton pot oxide on the particle size distribution. However, there was no appreciable change in the surface area due to the hammer milling process.
15

System analysis perspectives : lead-acid battery recycling in British Columbia, Canada

Alvares da Silva, Ana Carolina 05 1900 (has links)
This dissertation aims to use a system thinking approach to describe and evaluate the Lead-Acid Battery Recycling Program in British Columbia, compare it with other provincial regulated recycling programs and identify strategies on how it can be improved. The research is presented in the manuscript based format, comprised of four interrelated chapters. Following the introduction, chapter 2 describes a multiple regression analysis to assess how various factors identified by informed stakeholders have contributed to recycling rate in 14 transportation zones from 1995 to 2005. This study demonstrates that the existing recycling scheme ineffectively promotes recycling as it has achieved an average of 75% over the past 13 years with large fluctuations among transportation zones. The regression also shows that recycling rate of transportation zones are not highly influenced by LME lead prices and Transportation Incentive (which can be explained by the strong market power of the recycling plants responsible for setting up the price of scrap lead to which the collectors respond). Chapter 3 identifies key components that influence the performance of varied recycling systems based on a comparative analysis of provincial recycling systems informed by expert interviews. In chapter 4, comprehensive evaluation criteria for the lead-acid battery recycling program is developed based on objectives and performance measures elicited through an extensive stakeholder consultation process with various individuals and organizations. Fundamental objectives identified by stakeholders include: reduce environmental impacts, reduce occupational health impacts, reduce net costs, increase equity in resource consumption patterns and increase systematic learning. In chapter 5, we use multiple criteria decision analysis (MCDA) to design and assess effective recycling strategies to meet societal objectives previously identified in the chapter 4. Recycling strategies were compiled using the results of chapter 3. The results reveals that the optimal policy for the lead-acid battery recycling system combines a return to retailer program financed through an advanced disposal fee included in the battery price in combination with increased plant or recycling capacity domestically. This research also provides relevant contributions to the refining and application of value-focused thinking and decision analysis methodologies. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate
16

Použití konduktometrické metody pro měření vodivosti korozní vrstvy olověných slitin / Using konduktometric method for conductivity measurement of the corrosive layer of lead alloys

Neoral, Jiří January 2008 (has links)
Lead-acid batteries are the oldest and most common type of secondary cells. Their biggest use is as a power source for a car starter. Bipolar lead-acid batteries could also be used for new applications such as power sources for hybrid electrical vehicles (HEV) for their high power. But there are still many technical problems limiting its use in these applications, which have to be overcome. This could cover parasite reactions as is gas creation, heat removal from the battery and another big problem is substrate corrosion. This diploma thesis concerns the actual state of bipolar lead batteries in the world with detail orientation to substrate corrosion. This thesis describes the conductometric method of lotion conductivity measurement and its modification for measurement of lead grid conductivity. From that we can find out, that when material loses more conductivity, the greater the corrosion. This thesis describes needed preparative experiments for assurance, that the conductometric method can be used for corrosion speed measurement and there are other experiments testing different lead alloys for corrosion speed.
17

Advanced battery capacity estimation approaches for electric vehicles

沈維祥, Shen, Weixiang. January 2002 (has links)
published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
18

Predicting failure of remote battery backup systems

Unknown Date (has links)
Uninterruptable Power Supply (UPS) systems have become essential to modern industries that require continuous power supply to manage critical operations. Since a failure of a single battery will affect the entire backup system, UPS systems providers must replace any battery before it runs dead. In this regard, automated monitoring tools are required to determine when a battery needs replacement. Nowadays, a primitive method for monitoring the battery backup system is being used for this task. This thesis presents a classification model that uses data mining cleansing and processing techniques to remove useless information from the data obtained from the sensors installed in the batteries in order to improve the quality of the data and determine at a given moment in time if a battery should be replaced or not. This prediction model will help UPS systems providers increase the efficiency of battery monitoring procedures. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
19

An Enhanced State-of-Charge and State-of-Health Estimation Method Based on Ampere-Hour Counting for Lead-Acid Batteries

Huang, Yao-Feng 12 August 2008 (has links)
This thesis proposes an enhanced ampere-hour counting method based on the depth-of-discharge (DOD) to estimate the state-of-charge (SOC) and state-of-health (SOH) for lead-acid batteries. Not only the losses at different discharging currents, but also the releasable capacity at the exhausted state caused by the larger discharging current are considered and compensated. Furthermore, the SOH is revaluated at the exhausted state by the maximum releasable capacity, consequently leading to more accurate SOC estimation. Through the experiments that emulate practical operations, the experimental results reveal that the maximum error is less than 6 %.
20

Συσσωρευτές στα φωτοβολταϊκά συστήματα : Αντιμετώπιση των συνηθισμένων προβλημάτων των συσσωρευτών μολύβδου οξέος στα αυτόνομα φωτοβολταϊκά συστήματα

Τσιουμπρή, Ελένη 15 April 2013 (has links)
Η εμπειρία έχει δείξει ότι στα αυτόνομα φωτοβολταϊκά συστήματα, η μπαταρία είναι το πιο αδύναμο στοιχείο αφού το προσδόκιμο ζωής της είναι συνήθως αρκετά μικρότερο από ότι όλων των άλλων στοιχείων του συστήματος και για το λόγο αυτό είναι και το πιο ακριβό στοιχείο με το 30% ή και περισσότερο του κόστους ενός αυτόνομου φωτοβολταϊκού συστήματος καθ’όλη τη διάρκεια της ζωής του να οφείλεται στο σύστημα αποθήκευσης. Αντικείμενο αυτής της εργασίας είναι η μελέτη των προβλημάτων που αντιμετωπίζουν οι μπαταρίες μολύβδου οξέος (που είναι ο βασικός τύπος μπαταριών που χρησιμοποιείται για την αποθήκευση στα φωτοβολταϊκά συστήματα) και οι τρόποι αντιμετώπισής τους με σκοπό αφενός την επέκταση της διάρκειας της χρήσιμης ζωής των μπαταριών αυτών και αφετέρου τη μείωση του κόστους συντήρησης και αντικατάστασής τους. Ιδιαίτερη βαρύτητα δίνεται στο πρόβλημα της θειίκωσης, το οποίο έχει αποδειχθεί ο σημαντικότερος παράγοντας γήρανσης και τελικά καταστροφής της πλειοψηφίας των μπαταριών μολύβδου οξέος που χρησιμοποιούνται στα φωτοβολταϊκά συστήματα και παρουσιάζονται τεχνικές που μπορούν να χρησιμοποιηθούν για την πρόληψη και την αντιμετώπιση του πολύ σοβαρού αυτού προβλήματος. / Experience has shown that in stand alone photovoltaic systems, battery is the weakest element since its expected lifetime is usually considerably smaller than those of other elements. Thus its cost is the most expensive with 30% or above of the total cost of stand alone photovoltaic system throughout its whole lifespan. Subject of this dissertation is the study of problems that lead acid batteries face and the way to treat them. The aim is to extend their useful lifetime and the reduction of the cost of maintenance and replacement. The problem of sulphation is given special importance, since it has been proved that it constitutes the main aging factor for the majority of lead acid batteries used in photovoltaic systems. Suggestions for treatment are given.

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