In traditional investment decision making, one tool commonly used is the mean variance model, also known as an expected-value variance (EV) model, which evaluates the anticipated payout of different assets with respect to uncertainty where portfolios with higher risk demand higher expected returns from an individual. This thesis adapts this framework to a cost setting where decision makers are evaluating alternative physical assets that carry lifetime cost uncertainty for maintenance. Specifically, this paper examines homeowner choices for their home plumbing systems in the event of a pinhole leak, a tiny pin-sized hole that forms in copper, drinking-water pipes. These leaks can cause substantial damage and cost homeowners thousands of dollars in repairs. Since pinhole leaks are not related to the age of pipe material, a homeowner is subject to the risk of additional costs if a pinhole leak occurs again despite their repair efforts. The EV cost model in this paper defines two discrete choices for the homeowner in the event of a leak; to apply a simple repair at lower cost and higher future cost uncertainty, or to replace their plumbing with new pipe material, usually made of plastic, at a higher upfront cost but lower likelihood of future expenses. The risk preference of homeowners are demonstrated by their repair strategy selection, as well as the level of cost they incur to reduce uncertainty. Risk neutral individuals will select the repair strategy with the lowest lifetime expected cost and high variance, while risk averse homeowners will prefer to replace their plumbing with higher cost but lower variance. Risk averse individuals are also exposed to indirect costs, which is an additional unobserved cost in the form of a risk premium the homeowner is willing to pay to remove all uncertainty of future pinhole leak expense. Expected costs and variances are also higher for regions in the U.S. that experience elevated leak incident rates, known as hotspots. Using this mean variance cost framework, indirect cost can be quantified for homeowners in hotspot regions and compared to the rest of the U.S. to evaluate the magnitude of pinhole leak risk. The EV cost model estimates risk premiums on pinhole leaks to be $442 for homeowners in hotspots and $305 for those in the rest of the U.S. Finally, this paper examines the impact of pinhole leak cost uncertainty on the U.S. economy. Of an estimated $692 million in annual pinhole leak costs to homeowners, this study estimates a lower bound cost of $54 million per year (7.8% of estimated national annual cost) in risk premium that homeowners would be willing to pay to avoid pinhole leak cost uncertainty. Information in this study on the role of risk in home plumbing decisions and indirect costs would be helpful to policymakers and water utility managers as they deal with infrastructure management decisions. Furthermore, the EV cost methodology established in this paper demonstrates an effective use of mean variance modeling under cost uncertainty. / Master of Science / This paper examines homeowner choices for their home plumbing systems in the event of a pinhole leak, a tiny pin-sized hole that forms in copper, drinking-water pipes. These leaks can cause substantial damage and cost homeowners thousands of dollars in repairs. Since pinhole leaks are not related to the age of pipe material, a homeowner is subject to the risk of additional costs if a pinhole leak occurs again despite their repair efforts. This paper also examined costs in regions of the U.S. that experience elevated leak incident rates, known as hotspots. There were two primary choices assessed in this study for homeowners facing pinhole leaks: to either apply a simple repair today at lower cost but take on a higher chance of more pinhole leaks; or to replace their plumbing with new pipe material, usually made of plastic, at a higher overall cost but lower risk of another leak. Using a cost focused investment analysis, it was estimated that homeowners selecting the ‘safer’ replacement strategy would be willing to pay a minimum of $305 in additional cost if able to eliminate all possibility of another leak compared to those who opted for the more ‘riskier’ repair choice. Additionally, homeowners who live in hotspot regions who selected the replacement strategy were estimated to be willing to pay a minimum of $442 in additional cost to avoid pinhole leaks. At a national level, these pinhole leak-avoiding premiums equate to $54 million, about 7.8% of the estimated $692 million in costs spent on fixing pinhole leaks by U.S. homeowners each year. Information in this study on homeowner preferences and pinhole leak would be helpful to policymakers and water utility managers as they deal with infrastructure management decisions.

Pinhole leaks in copper plumbing pipes are a big concern for the homeowners. The problem is spread across the nation and remains a threat to plumbing systems of all ages. Due to the absence of a single acceptable mechanistic theory no preventive measure is available to date. Most of the present mechanistic theories are based on analysis of failed pipe samples however an objective comparison with other pipes that did not fail is seldom made. The variability in hydraulic and water quality parameters has made the problem complex and unquantifiable in terms of plumbing susceptibility to pinhole leaks. The present work determines the spatial and temporal spread of pinhole leaks across United States. The hotspot communities are identified based on repair histories and surveys. An assessment of variability in water quality is presented based on nationwide water quality data. A synthesis of causal factors is presented and a scoring system for copper pitting is developed using goal programming. A probabilistic model is presented to evaluate optimal replacement time for plumbing systems. Methodologies for mechanistic modeling based on corrosion thermodynamics and kinetics are presented. / Master of Science

This practice-based thesis presents the results of experimental research devoted to ethnic tourism among the Kayan minority and has involved the interconnection of artistic and anthropological languages. Known worldwide for the traditional female custom of wearing a long coiled brass necklace aimed at causing a considerable extension to the neck, the Kayan are a Tibeto-Burman ethnic group originally from Burma. Due to the prolonged civil war in their own homeland, a large number of Kayan recently fled from Burma to refuge in neighbouring Thailand. Here, over the past years, in response to the “incisive” tourism policy promoted by the Thai government in the northern areas of the country, some families, abandoning the refugee camps where they were hosted, have been resettled in several new villages open to tourists, on payment of a modest entrance fee. Here the Kayan, their culture and their daily life, have been transformed into an authentic tourist attraction capable of drawing about 10,000 visitors a year. Founded on a strictly “visual media primitivist” approach and inspired by its peculiar aesthetics – as systematically presented in the first, theoretical, section of the thesis –, the enquiry involves a multimedia perspective. In such a context, analogue photography and filmmaking, creative writing and sound composition have been combined to give concrete shape to an original artwork firmly grounded in ethnographic practice. The choice, far from being a solely arbitrary and subjective option, has indeed been motivated by the critical employment of specific theoretical assumptions of some of the most recent streams of anthropology and epistemology of the human sciences. The multidisciplinary methodology adopted to develop the research, as well as the multifaceted language employed to display its results, represent an innovative and experimental way of approaching the complex theme of cultural identity in present-day Asian contexts, as well as of highlighting the most aesthetic and philosophic implications connected to the revival of analogue vintage media in contemporary artistic practice.

Submitted by Irvana Coutinho (irvana@ufpa.br) on 2017-02-07T16:41:41Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ClicEjaFuro.pdf: 6478219 bytes, checksum: 6f2169b8cd87c2905075ff1a34f5f062 (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-02-07T16:42:26Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ClicEjaFuro.pdf: 6478219 bytes, checksum: 6f2169b8cd87c2905075ff1a34f5f062 (MD5) / Made available in DSpace on 2017-02-07T16:42:26Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ClicEjaFuro.pdf: 6478219 bytes, checksum: 6f2169b8cd87c2905075ff1a34f5f062 (MD5) Previous issue date: 2012-03-01 / O presente trabalho revela dois processos de experimentações com a imagem através da fotografia: o primeiro direcionado a uma turma de alunos da Educação de Jovens e Adultos (EJA) de uma Escola Pública de Belém/PA, e o segundo direcionado a um grupo de jovens de uma comunidade do Bairro da Terra Firme da periferia de Belém/PA. Buscando deflagrar novas interpretações e subjetividades a partir de experimentações com a fotografia em seus múltiplos aspectos, apontamos nossas lentes para além de uma produção técnica, na direção de uma percepção que adentre o que se vê daqueles que constroem a sua própria identidade. Todo o processo vivenciado esteve preocupado em desenvolver o senso estético dos alunos e principalmente em reeducar o olhar a uma postura mais sensível, atenta aos detalhes do dia-a-dia e crítica, partindo dos princípios da observação, experimentação e pesquisa. Optamos por este tipo de abordagem por acreditar que a fotografia, dada toda uma trajetória imagética, histórica e conceitual, dentro e fora de um contexto escolar, pode contribuir para a formação dos indivíduos na sociedade. / This study reveals two processes of experimentation with the image through photography: the first aimed at a group of students of Youth and Adults (EJA) from a Public School in Bethlehem / PA, and the second directed at a group of young community of the District of Mainland on the outskirts of Bethlehem / PA. Seeking to unleash new subjectivities and interpretations from experimenting with photography in its many aspects, we point our lenses as well as a production technique, in the direction of a perception that step into what we see those who build their own identity. The whole process experienced was concerned to develop the aesthetic sense of students and especially in re-educate the eye to a more sensitive, attentive to detail the day-to-day and critical, based on principles of observation, experimentation and research. We chose this approach because we believe that photography, all given end trajectory imagery, historical and conceptual, within and outside a school context, can contribute to the training of individuals in society.

No description available.

L'objectif de ce travail est de décrire des modélisations des points de vue et des changements de points de vue d'images d'un objet planaire dans les algèbres de Clifford conformes. Nous généralisons le modèle conforme de l'espace euclidien à travers une famille à deux paramètres d'horosphère, chacune d'entre elles étant plongée dans un espace vectoriel réel de dimension 4 muni d'une métrique équivalente à la métrique de Minkowski. Nous décrivons par la suite deux approches pour mettre en œuvre ces modèles conformes généralisés pour les représentations d'images. L'idée de base est d'encoder les distorsions perspectives de l'objet causées par la variation du paramètre de latitude de la caméra au travers des paramètres d'une horosphère. La première approche consiste à considérer les horosphères de l'espace de Minkowski de dimension 4 pour encoder les points de vue. Les changements de points de vue sont alors linéarisés à travers un groupe de transformations linéaires et conformes de cet espace. Cette approche est ensuite généralisée en décrivant les points de vue à travers les objets d'un groupoïde dont les morphismes sont des diagrammes commutatifs qui représentent les changements de points de vue. Ainsi, une image conforme est décrite par une application définie sur une horosphère à deux paramètres. L'action du groupoïde sur l'ensemble des images conformes nous conduit à associer à tout objet planaire l'orbite de toutes ses images conformes obtenues à partir de tous les points de vue. / Our purpose in this work is to introduce representations of image viewpoints and viewpoint changes of a planar object in conformal Clifford algebras. Our important preliminary contribution is a generalization of the conformal model of the Euclidean space through a two-parameter family of horospheres. Each one of these is embedded into a real vector space of dimension 4 equipped with a metric equivalent to the Minkowski metric. We describe two approaches that make use of these generalized conformal models for image representations. These are based on modelings of perspective distortions of the object caused by a variation of the latitude angle of the camera. First, we model the image viewpoints by the horospheres of the Minkowski space of dimension 4. In this setting, the viewpoint changes are linearized through a group of linear conformal transformations of this space. This approach is generalized by describing the viewpoints through the objects of a groupoid whose morphisms are commutative diagrams that model the viewpoint changes. A conformal image is then described as a map defined on a horosphere. The action of the groupoid on the set of conformal images leads us to associate with every planar object the orbit of its conformal images from all viewpoints.

This work deals with the orientation of the camera in real-time with a single camera. Offline methods are described and used as a reference for comparison of a real-time metods. Metods work in real-time Monocular SLAM and PTAM methods are there described and compared. Further, paper shows hints of advanced methods whereas future work is possible.

No description available.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23754号 / 医博第4800号 / 新制||医||1055(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 木村 剛, 教授 山下 潤, 教授 YOUSSEFIAN Shohab / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

This thesis addresses simulation of electrochemical experiments, with an emphasis on processes of diffusional mass transport to electrode surface. Following system has been studied: • Applying theoretical modeling and experimentation is shown that even significant surface roughness produced by deliberate polishing or scratching is not sufficient to be distinguished in cyclic voltammetry experiments conducted under the usual conditions. In stripping voltammetry experiment the shape of the voltammograms strongly depends on the model of the electron transfer but is not always sensitive to the precise model of the electrode surface; the conditions under which this is the case are identified, and generic roughness effects on stripping voltammetry are quantified. Electrode roughness can have a significant effect on the stripping of the metals from the solid electrode especially in respect of the voltammetric waveshape. • We first consider two different models of electrodes covered with electroinactive layers: the electrode is covered with a uniform layer and the layer contains pinholes. Both models are simulated and then compared to identify conditions under which they can be distinguished. Next we propose generic model to predict the influence of electroactive layer on the cyclic voltammetric. The conditions under which deviation from the behavior of a planar electrode are predicted. • We first consider one electron, one proton and next two electron, two proton reduction of surface bound species. Two mechanisms of reaction are considered: stepwise and concerted. Voltammetry studied under the three regimes of protons mass transport: infinitely fast (fully buffered solution), infinitely slow (infinitely high surface coverage of electrode) and intermediate case of finite rate of diffusional mass transport to electrode surface. Types of voltammograms observed in each case are presented and discussed. • Theory of chronoamperometry on disc and ring-recessed microelectrodes and their arrays is reported. Three and four different regimes of transient current versus time can be observed at microelectrode arrays of disc and ring electrodes, accordingly. A generic, accurate and easy to use method of experimental chronoamperometric data analysis is proposed. It is shown that the method can be applied to the simultaneous measurement of D and nC in solution. • The fabrication, characterization, and use of arrays of ring-recessed disk generator-colector microelectrodes are reported. Experiments and simulations relating to time- of-flight experiments in which material electrogenerated at a disk is diffusionally transported to the ring are reported. We further study voltammetry of electrochemically active species which undergoes first and second order chemical reactions. Current transients are found to be sensitive to the diffusion coefficient of both the reduced and oxidised species as well as to the rate of the chemical reaction and its mechanism.