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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.
91

Dynamic Demand for New and Used Durable Goods without Physical Depreciation

Ishihara, Masakazu 31 August 2011 (has links)
This thesis studies the interaction between new and used durable goods without physical depreciation. In product categories such as CDs/DVDs and video games, the competition from used goods markets has been viewed as a serious problem by producers. These products physically depreciate negligibly, but owners' consumption values could depreciate quickly due to satiation. Consequently, used goods that are almost identical to new goods may become available immediately after a new product release. However, the existence of used goods markets also provides consumers with a selling opportunity. If consumers are forward-looking and account for the future resale value of a product in their buying decision, used goods markets could increase the sales of new goods. Thus, whether used good markets are harmful or beneficial to new-good producers is an empirical question. To tackle this question, I extend the previous literature in three ways. First, I assemble a new data set from the Japanese video game market. This unique data set includes not only the sales and prices of new and used goods, but also the resale value of used copies, the quantity of used copies retailers purchased from consumers, and the inventory level of used copies at retailers. Second, I develop a structural model of forward-looking consumers that incorporates (i) new and used goods buying decisions, (ii) used goods selling decisions, (iii) consumer expectations about future prices of new and used goods as well as resale values of used goods, and (iv) the depreciation of both owners' and potential buyers' consumption values. Third, I develop a new Bayesian estimation method to estimate my model. In particular, my method can alleviate the computational burden of estimating non-stationary discrete choice dynamic programming models with continuous state variables that evolve stochastically over time. The estimation results suggest that consumers are forward-looking in the Japanese video game market and the substitutability between new and used video games is quite low. Using the estimates, I quantify the impact of eliminating the used video game market on new-game revenues. I find that the elimination of used video game market could reduce the revenue for a new game.
92

Dynamic Demand for New and Used Durable Goods without Physical Depreciation

Ishihara, Masakazu 31 August 2011 (has links)
This thesis studies the interaction between new and used durable goods without physical depreciation. In product categories such as CDs/DVDs and video games, the competition from used goods markets has been viewed as a serious problem by producers. These products physically depreciate negligibly, but owners' consumption values could depreciate quickly due to satiation. Consequently, used goods that are almost identical to new goods may become available immediately after a new product release. However, the existence of used goods markets also provides consumers with a selling opportunity. If consumers are forward-looking and account for the future resale value of a product in their buying decision, used goods markets could increase the sales of new goods. Thus, whether used good markets are harmful or beneficial to new-good producers is an empirical question. To tackle this question, I extend the previous literature in three ways. First, I assemble a new data set from the Japanese video game market. This unique data set includes not only the sales and prices of new and used goods, but also the resale value of used copies, the quantity of used copies retailers purchased from consumers, and the inventory level of used copies at retailers. Second, I develop a structural model of forward-looking consumers that incorporates (i) new and used goods buying decisions, (ii) used goods selling decisions, (iii) consumer expectations about future prices of new and used goods as well as resale values of used goods, and (iv) the depreciation of both owners' and potential buyers' consumption values. Third, I develop a new Bayesian estimation method to estimate my model. In particular, my method can alleviate the computational burden of estimating non-stationary discrete choice dynamic programming models with continuous state variables that evolve stochastically over time. The estimation results suggest that consumers are forward-looking in the Japanese video game market and the substitutability between new and used video games is quite low. Using the estimates, I quantify the impact of eliminating the used video game market on new-game revenues. I find that the elimination of used video game market could reduce the revenue for a new game.
93

An Investigation of Some Problems Related to Renewal Process

Yeh, Tzu-Tsen 19 June 2001 (has links)
In this thesis we present some related problems about the renewal processes. More precisely, let $gamma_{t}$ be the residual life at time $t$ of the renewal process $A={A(t),t geq 0}$, $F$ be the common distribution function of the inter-arrival times. Under suitable conditions, we prove that if $Var(gamma_{t})=E^2(gamma_{t})-E(gamma_{t}),forall t=0,1 ho,2 ho,3 ho,... $, then $F$ will be geometrically distributed under the assumption $F$ is discrete. We also discuss the tails of random sums for the renewal process. We prove that the $k$ power of random sum is always new worse than used ($NWU$).
94

Understanding circumscribed interests in individuals with autism-spectrum disorders and how they relate to families.

Gass, David S.J. 08 October 2013 (has links)
Autism-spectrum disorders (ASDs) are a group of neurodevelopmental disorders that are becoming increasingly more prevalent. A diagnostic criterion for autism is the presence of restricted, repetitive behaviours (RRBs), one of which is the intense fascinations for virtually any topic: circumscribed interests (CIs). CIs have the potential to be used for motivational purposes. This study employed semi-structured interviews using Interpretative Phenomenological Analysis (IPA) with individuals with ASDs and their parents. In total, 11 families participated in this study, comprising 33 individuals (16 parents and 17 individuals with ASDs). This study found five themes: He's Very Unique; They Don't Realize that Not Everyone Lives and Thinks the Same Thing All the Time; We Couldn't even Pronounce the Names of These Dinosaurs, and Jason was Telling Us; You Can't Change Them, You Can Only Love Them; and So I Can Do My Job at the Same Time and Observe the Weather at the Same Time.
95

Shifting cultures of recycled style : a history of second-hand clothing markets in Montreal

Diggins, Kimberly A. January 1998 (has links)
Shifting cultures of recycled style: a history of second-hand clothing markets in Montreal draws a cultural history of the evolving circuits through which discards of the fashion system pass. The focus is on three manifestations of the market: the female-dominated charity circuits of the nineteenth-century into which the flow of used goods was redirected following the introduction of mass-produced garments; the revival of cast-off clothing's stylish potential by punk and grunge subcultures in their respective creations of a poverty aesthetic; and the more heterogeneously mainstream market of the late 1980s and 1990s operating within a consumer environment seeped in nostalgia. / The second-hand market is a facet of the fashion system receiving scant attention by the academic community. This study aims to redress the oversight by demonstrating how much of a given society is revealed through the ways in which its members manage the matter of sartorial waste.
96

Evaluation of informal sector activities in Germany under consideration of electrical and electronic waste management systems

Lange, Ulrike 24 September 2013 (has links) (PDF)
The informal sector is described as groups of persons who act in parallel to official waste management systems without official authorisation. Such informal activities can result in risks as well as benefits both to the environment and involved stakeholders, which explains the continuing lively discussions in politics, science and society. Transhipments of waste electrical and electronic equipment (WEEE) are increasingly focused in Germany. In addition to informal exports via the port of Hamburg to countries such as China, Ghana or Nigeria, informal transports to Eastern European countries have been recognised for decades. This paper describes investigations regarding the characteristics, transhipped amounts as well as the eco-efficiency of informal sector activities originating from Eastern European countries, while thereby highlighting transhipments of used appliances to destination countries and a corresponding sale for reuse. Investigations reveal that a majority of informal collectors originate from Poland, Czech Republic, Hungary and Romania and are recognised across Germany. A high WEEE specialisation was determined, whereby average annual transhipped amounts are estimated at 77,000 tons. Collected materials are transhipped and partially sold for reuse. A case study considers the example of Polish informal collectors. The ratio between economic and environmental performance reveal that informal sector reuse activities in Poland achieve a higher environmentally sound performance in comparison to further usage of appliances under consideration. The informal collection of a television in Germany (and subsequent reuse in Poland) causes 8.34 kg less specific CO2 emissions per spend-costs (€) than the production, usage and further use in Poland. Conversely, a further use of a television in Germany only results in 2.2 kg less CO2 emissions per spend-costs (€). These results demonstrate that reuse as a result of informal sector activities can have a positive effect. Future electrical and electronic products available for reuse will have lower energy consumptions. A positive contribution to resource protection is thereby achieved while extending already short life cycles. Taking into account a dependency on collections with respect to their income, a pure ban of informal sector activities would therefore be socially counterproductive. A structured and controlled accomplishment of informal collection processes would open up new opportunities to enlarge the (already existing) concept of reuse at an international level.
97

Valorisation non alimentaire des huiles de friture usagées en tant que biolubrifiants / Non food valorisation of use frying oils as lubricants

Essono Abaga, Ange-Godefroy 06 December 2013 (has links)
Le projet de recherche appliquée portait sur la valorisation des huiles de friture usagées en tant que biolubrifiant pour chaîne de tronçonneuse. Ces huiles collectées dans les différentes enseignes de restauration présentent une teneur élevée en composés polaires, une acidité élevée, une grande variabilité dans leur composition en acides gras, relatives aux différentes marques d'huiles végétales utilisées. Ces mélanges d'huiles végétales (colza, tournesol, arachide, palme, coprah), déjà valorisés dans la filière des biocarburants, présentent des propriétés physico-chimiques intéressantes (indice de viscosité, biodégradabilité, composition en acides gras) qui leur permettraient de concurrencer les lubrifiants d'origine minérale ou végétale que l'on trouve sur le marché, notamment dans le secteur forestier. Un procédé d'ultrafiltration par membrane céramique a permis de réduire la teneur en composés polaires ainsi que l'acidité consécutive au procédé de friture profonde, tout en réduisant le phénomène de colmatage. L'utilisation de la méthodologie des surfaces de réponse a contribué à optimiser les paramètres de température, pression, porosité des membranes, afin d'améliorer les débits de filtration. La formulation de ce biolubrifiant à partir du mélange d'huiles obtenu, optimisé par plan de mélanges, a conduit à l'obtention d'un produit de grade ISO 150 dont les caractéristiques «filant», «adhésivité » et « point d'écoulement » répondent au cahier des charges. Une étude de biodégradabilité selon la norme OCDE 301B a montré que l'huile formulée est biodégradable à 90%, faiblement toxique selon les tests OCDE 201, 202, 203, et ne présente pas d'allergénicité / The applied research project focused on the valuation of used frying oils as bio-lubricant for chainsaw. Those collected in the various restaurant chains oils have a high content of polar compounds , high acidity , a great variability in their composition , fatty acids on different brands of vegetable oils . These mixtures of vegetable oils (rapeseed, sunflower , peanut, palm , coconut ) , already valued in the biofuels , have interesting physicochemical properties ( viscosity , biodegradability , fatty acid composition ) that would allow them to compete with lubricants mineral or vegetable that is found on the market, particularly in the forestry sector origin . A method of ceramic membrane ultrafiltration has reduced content of polar compounds and the subsequent acidity of the deep frying process , while reducing the clogging phenomenon . The use of response surface methodology has helped to optimize the parameters of temperature, pressure, porous membranes, to improve filtration rates . The formulation of this biolubricant from the mixture of oils obtained optimized plan mixtures led to the production of a product of ISO 150 grade which features " spinning ", " stickiness " and " pour point " meet the specifications . A study of biodegradability according to OECD 301B showed that formulated oil is 90% biodegradable , low toxicity tests according to OECD 201, 202, 203, and does not show allergenicity
98

[en] PROPOSAL FOR ALTERNATIVE STATISTICAL PROTOCOLS FOR PROFICIENCY TESTING PROGRAMS / [pt] PROPOSTA DE PROTOCOLOS ESTATÍSTICOS ALTERNATIVOS PARA PROGRAMAS DE ENSAIOS DE PROFICIÊNCIA

CÍNTIA DE HOLLEBEN 21 September 2018 (has links)
[pt] O objetivo dessa dissertação é propor protocolos estatísticos alternativos ao atual praticado pela American Society for Testing and Materials (ASTM) para a determinação do desempenho dos laboratórios participantes de Ensaios de Proficiência (EP) utilizando estatística robusta. A participação em EP é um requisito compulsório à conformidade nas certificações e acreditações para laboratórios de ensaio e calibração. O Programa de EP da ASTM considera o valor de consenso para prover os escores dos participantes. O modelo para estimar os escores, ZASTM, se baseia na média amostral (valor designado, VD) e no desvio padrão amostral (desvio padrão para a proficiência, DPP). Neste cenário, há necessidade de tratamento exaustivo dos dados, motivação para este estudo, incluindo o tratamento de outliers e a investigação de existência de distribuição normal (Gaussiana). Neste estudo, os protocolos propostos (nIQR e MADe) consideram o emprego de estatísticas robustas, mais resistentes à presença de outliers, os quais ocasionam desvios da normalidade desejada. Os resultados da comparação do protocolo ASTM com os protocolos propostos, em dados da matriz de óleos lubrificantes, reportados ao provedor ASTM, revelam haver diferença entre as médias ou entre as variâncias dos escores produzidos pelos diferentes protocolos ao nível de 5 porcento de significância, ocasionando mudança na classificação do desempenho dos laboratórios. Conclui-se que os protocolos estatísticos alternativos propostos apresentaram a vantagem de dispensar o tratamento de outliers e a investigação da distribuição dos dados, sendo que o protocolo MADe ainda apresentou redução na incerteza de medição associada ao valor designado por consenso. / [en] The objective of this dissertation is to propose statistical protocols that are alternative to the current one applied by the American Society for Testing and Materials (ASTM) to determine the performance of participants laboratories of Proficiency Testing (PT) by using robust statistics. Participation in PT is a mandatory requirement for compliance in certifications and accreditations for testing and calibration laboratories. The ASTM EP Program employs the consensus value to provide the participants scores. The method for estimating the scores, ZASTM, is based on the sample data mean (assigned value, AV) and the sample data standard deviation (standard deviation for proficiency assesment, SDPA). In this case, it is necessary an exhaustive treating of the data, motivation for this study, including the treatment of outliers and the investigation of existence of normal distribution (Gaussian). In this study, the proposed protocols (nIQR and MADe) consider the application of robust statistics, which are more resistant to the presence of outliers, which cause deviations from the desired normality. The results of the ASTM protocol comparison with the proposed protocols in the lubricant oil matrix data reported to the ASTM provider show a difference between the means or between the variances of the scores produced by the different protocols at the 5 per cent level of significance, causing variation in the classification of laboratory performance. It is concluded that the proposed alternative statistical protocols had the advantage of dispensing the outliers treatment and the investigation of the data distribution, and the MADe protocol still showed reduction in the measurement
99

Consumer behavior analysis through nudging : A study on nudging of single-used hospital garments in healthcare sector of Region Östergötland

Mikhaylevskaya, Valentina January 2018 (has links)
Region Östergötland has encountered issue in ecological and economical overconsumption of single-used garments in healthcare sector among medical staff in Universitetssjukhuset Linköping. Proper approaches to reach solutions towards decrease of usage of single-used garments were targeted to be implemented for employees of healthcare sector. Two goals were established for this study. First of all, it was aimed to analyse consumer behaviour of employees in healthcare sector of Östergötland region to find out reasons that lay behind increase of single-time garments by employees. Secondly, the aim was targeted to examine what nudging techniques, if any, are feasible to use in positively changing current consumer behavior. The findings showed that nudging has a strong potential to be regarded as an effective tool in influencing healthcare workers of Linköping University Hospital disposable garments usage. Main behavioural reasons that triggered increase of disposable garments usage were detected as lack of information and old habits of medical staff. Application of information disclosure, framing, feedback and social norms nudging techniques were identified to have promising possibilities in impacting current behaviour and raise healthcare workers awareness about their consumption patterns.
100

Díla audiovizuální / An audiovisual work

Slunčíková, Michaela January 2011 (has links)
T h e s i s o n A u d i o v i s u a l w o r k s - A b s t r a c t The thesis deals with the legal regulation of audiovisual works in the Czech legal order. The thesis analyzes this legislation in detail with regard to the audiovisual experience, and also discusses some of the practical issues arising during the production and use of audiovisual works. In the introduction to the thesis, individual sources of legal regulation of audiovisual works are listed and also the key issues covered by the thesis. The first chapter defines the term of "an audiovisual work" and it also focuses on the development of the legal definition of this term. The second chapter is regarding the author of an audiovisual work; it describes who was considered to be an author of the audiovisual work in the past and who is considered to be an author under the current legislation. The third chapter defines another important term of the legal regulation of audiovisual works, namely so-called "works audiovisually used" (works which are used in the audiovisual work). It is also regarding the authors of works audiovisually used. The term "works audiovisually used" as such is not defined by Czech law and therefore its interpretation results in frequent inconsistencies. This thesis tries to find solution for these interpretation differences....

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