Dissertations / Theses: 'Equilibrium composition of the environment'

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Гончар, Кирило Романович. "Високотемпературна нітроцементація цирконію." Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/28151.

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В роботі досліджено можливість одночасного насичення цирконію в продуктах розкладу оксалату амонію. Теоретично розраховано та експе-риментально підтверджено співвідношення компонентів рівноважного складу реакційного середовища для нанесення комплексних покриттів методом дифузійного насичення азотом, вуглецем та киснем за участю водню. Склад як газової так і конденсованої фази залежить від складу та співвідношення реа-гентів в насичуючій суміші; Формування комплексних покрит-тів на основі сполук цирконію ZrN, ZrO2, та ZrС з високою твердістю та добрим зчепленням з ос-новою можна вважати позитивним досягненням даного дослідження. Такі покриття можуть бути перспе-ктивними при використанні в медичній, хімічній промисловості та атомній енергетиці.
In this work the possibility of simul-taneous saturation of zirconium in products of decomposition of am-monium oxalate has been investigat-ed. The ratio of components of the equi-librium composition of the reaction medium to the application of com-plex coatings by diffusion saturation with nitrogen, carbon and oxygen with the participation of hydrogen has been theoretically calculated and experimentally confirmed. The com-position of both the gas and the con-densed phase depends on the com-position and ratio of reagents in the saturated mixture . Calculated reaction formation nitride ZrN, oxide ZrO2, zirconium carbide ZrC with hydrogen and the reaction between each of nitrogen, oxygen, carbon and hydrogen. Thermody-namic probability of formation of carbides, nitrides and oxides decreas-es with increasing temperature;

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Pötzelberger, Klaus, and Leopold Sögner. "Equilibrium and learning in a non-stationary environment." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2001. http://epub.wu.ac.at/1708/1/document.pdf.

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This article considers three standard asset pricing models with adaptive agents and stochastic non-stationary dividends. We assume that the parameters are estimated by exponential smoothing, such that prices and returns remain random variables. This paper provides sufficient conditions for the ergodicity of the return process and checks whether the perceived law assumed by the bounded rational agents can be considered to be sound with the returns observed. (author's abstract)
Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

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HUANG, Cuiting. "Service composition in converged service environment." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00762644.

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The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery

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Huang, Cuiting. "Service composition in converged service environment." Thesis, Evry, Institut national des télécommunications, 2012. http://www.theses.fr/2012TELE0009/document.

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L'objectif de cette thèse est de fournir des mécanismes améliorés pour déployer des services compétitifs par des manières rapides et rentables. Nous proposons un modèle de composition de service basé sur un environnement IMS/Web convergent. Ce modèle permet aux utilisateurs non professionnels de réutiliser les services existants pour créer de nouveaux services facilement. Pour améliorer la fonctionnalité de composition automatique, trois stratégies, y compris mise à jour passive, mise à jour active et mise à jour hybride sont proposées et analysées. Nous introduisons ensuite une plateforme centralisée d'exposition de service pour une variété de services, y compris services de Télécom / Web / appareil / services générés par les utilisateurs. Cette plateforme vise à renforcer les caractéristiques de centrée-sur-utilisateur et convergence, et fournir l'accès unifié à différents services. Par la suite, deux modèles basés sur le P2P sont conçus pour compléter le modèle centralisé: i) Un modèle hiérarchique basé sur Chord pour garantir l'efficacité de la découverte de services. Il adopte le concept de publication et découverte de service abstrait pour permettre à la recherche de service ambiguë. ii) Un modèle de superposition-triplex et P2P basé, qui cible principalement des services offerts par les appareils. Dans ce modèle, nous utilisons des passerelles pour déléguer des appareils résidant en eux pour l'exposition globale de services, et utilisons une architecture basée sur une superposition triplex, qui comprend une couche P2P non structurée, une couche de réseau sémantique (SON), et une couche de dépendance de service, pour la partage de l'information de service et la découverte de services
The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery

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Hajji, Wajdi. "Dynamic service chain composition in virtualised environment." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/36076.

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Network Function Virtualisation (NFV) has contributed to improving the flexibility of network service provisioning and reducing the time to market of new services. NFV leverages the virtualisation technology to decouple the software implementation of network appliances from the physical devices on which they run. However, with the emergence of this paradigm, providing data centre applications with an adequate network performance becomes challenging. For instance, virtualised environments cause network congestion, decrease the throughput and hurt the end user experience. Moreover, applications usually communicate through multiple sequences of virtual network functions (VNFs), aka service chains, for policy enforcement and performance and security enhancement, which increases the management complexity at to the network level. To address this problematic situation, existing studies have proposed high-level approaches of VNFs chaining and placement that improve service chain performance. They consider the VNFs as homogenous entities regardless of their specific characteristics. They have overlooked their distinct behaviour toward the traffic load and how their underpinning implementation can intervene in defining resource usage. Our research aims at filling this gap by finding out particular patterns on production and widely used VNFs. And proposing a categorisation that helps in reducing network latency at the chains. Based on experimental evaluation, we have classified firewalls, NAT, IDS/IPS, Flow monitors into I/O- and CPU-bound functions. The former category is mainly sensitive to the throughput, in packets per second, while the performance of the latter is primarily affected by the network bandwidth, in bits per second. By doing so, we correlate the VNF category with the traversing traffic characteristics and this will dictate how the service chains would be composed. We propose a heuristic called Natif, for a VNF-Aware VNF insTantIation and traFfic distribution scheme, to reconcile the discrepancy in VNF requirements based on the category they belong to and to eventually reduce network latency. We have deployed Natif in an OpenStack-based environment and have compared it to a network-aware VNF composition approach. Our results show a decrease in latency by around 188% on average without sacrificing the throughput.

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Blakstad, Eirik. "City Guide: Service Composition in an Urban Environment." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9916.

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The aim of this thesis has been to develop and validate the user interface of a service composition tool for creating mobile tourist services in a city environment. The project has been conducted in cooperation with SINTEF and the Norwegian research project UbiCompForAll. As part of this thesis, a number of scenarios were created initially, showing what kind of functionalities accessed using mobile devices might be useful for tourists in the city. Based on these scenarios, the graphical user interface of a composition service tool was created and then assessed through the involvement of several users using a paper prototyping approach. The results from the paper prototyping assessment showed that the proposed interface is generally easy to understand and use, although there were a number of improvements necessary in the areas of information abstraction, module naming and letting users be able to see the final product of the composition. In addition, as part of the assessment of the proposed interface, the realizability of the services specified using this interface was evaluated. An architecture for the service derived from the specification developed by the user was defined. This enabled us to check that all the information necessary for creating the composed services can be provided when using the proposed user interface.

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Pasztor, Egon 1975. "A graphical environment for gestural computer-aided composition." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/62375.

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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2002.
Includes bibliographical references (leaves 102-103).
I have designed and implemented a software environment, a Windows application called Hyperscore, that presents a novel, easy-to-learn interface for composing richly textured music through line gestures. The program allows the user to command a set of music-manipulation algorithms written by Mary Farbood [Farbood, 2001]. The interface is both compelling and interesting for musically untrained users, and rich enough that such users, after sufficient practice, can create music that professional musicians find to be of high quality. While many musical composition programs geared for musically untrained users exist, it is its unique user interface, its use of freely drawn line-gestures, zooming navigation, and simple symbolic icons, that helps make this program unique. The program was designed to enable musically untrained children, ages ten or older, to compose three-minute pieces for a string orchestra, given only a week or so of two-hour daily workshops. The program succeeded in this, and has been presented to audiences in Berlin, Dublin, and Glasgow as a part of Toy Symphony. The program has also been made available for download.
by Egon Pasztor.
S.M.

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Clegg, Nicola Aylsa. "Modelling sea-salt aerosol composition in the marine environment." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286292.

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Anderson, Tim M. "E-SCAPE : an extendible sonic composition and performance environment." Thesis, University of York, 1993. http://etheses.whiterose.ac.uk/21040/.

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Oliva, Martin Lisandro. "Genotype, environment and GE interaction effect on soybean oil composition." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4253.

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Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (December 18, 2006). Includes bibliographical references.

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TAKEBE, Masamichi, and Koshi YAMAMOTO. "Relative REE abundances of porewater in Pacific pelagic sediment: estimation by equilibrium calculations based on REE composition of Mn-oxide and apatite components." 名古屋大学博物館, 2007. http://hdl.handle.net/2237/12208.

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Avellar, Marcio Guilherme Bronzato de. "Different approaches to the Composition of Neutron Stars and their Environment." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/14/14131/tde-12062012-213540/.

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Even after 80 years of intense research, the composition of neutron stars remains unknown, since both the dense matter in the interior of these compact objects and the matter moving around them are in extreme physical conditions, unreproducible in terrestrial laboratories. In this Thesis, we follow four different interconnected ways to approach these extreme objects. First, we explore the mathematical structure of neutron stars, building solutions parametrised solely by the central density, what are very appropriate to study the structural behaviour of these stars in different situations. Then, we adopted a novel approach, the information theory, to infer a hierarchy of equations of state, showing that quark stars would be, by its configuration, favoured by Nature. Studying the X-ray emission arising from the low-mass binary system 4U 1608-52, which contains a neutron star, we limit the physical size of the emitting source, showing that it should not be far from the surface of the compact star. For this, we employed a technique to calculate the time lags never used before. Finally, we show that it is possible to obtain restrictions on the strange quark mass and the energy gap of the CFL directly from observations. We conclude this Thesis with the statement that the strange quark matter is, structurally and energetically favoured by Nature, though there is an entropic barrier to be overcame and a minimum central density to be reached just after the collapse of the progenitor star. If this barrier is actually overcame in Nature, only refined observations will tell.
Mesmo depois de 80 anos de pesquisas intensas, a composição das estrelas de nêutrons permanece desconhecida, uma vez que tanto a matéria densa do interior desses objetos compactos quanto a matéria se movendo em torno deles encontram-se em condições físicas extremas, irreprodutíveis em laboratórios terrestres. Nessa Tese, seguimos quatro diferentes caminhos interconectados para abordar esses objetos extremos. Primeiramente, exploramos a estrutura matemática das estrelas de nêutrons, construindo soluções parametrizadas unicamente pela densidade central, apropriadas para estudar o comportamento estrutural dessas estrelas em diversas situações. Em seguida, adotamos uma abordagem nova, a teoria da informação, para inferir uma hierarquia de equações de estado, mostrando que as estrelas de quarks seriam, por sua conformação, favorecidas na Natureza. Estudando a emissão em raios-X advinda do sistema binário de baixa massa 4U 1608--52, que contém uma estrela de nêutrons, limitamos o tamanho físico da fonte emissora, mostrando que não deve estar longe da superfície da estrela compacta. Para isso, empregamos uma técnica inédita no cálculo dos \"time lags\". Por fim, mostramos que é possível obter restrições à massa do quark estranho e ao \"gap\" de energia da CFL diretamente das observações. Concluímos essa Tese com a afirmação de que a matéria estranha é, estrutural e energeticamente, favorecida pela Natureza, muito embora exista uma barreira entrópica a ser superada e uma densidade central mínima a ser atingida logo após o colapso da estrela progenitora. Se essa barreira foi superada na Natureza, apenas observações futuras mais refinadas dirão.

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Cubitt, Tania Anne. "Environmental factors, pasture composition, growth rate and puberty in growing Thoroughbreds." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/31576.

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A rapid growth phase often occurs with the onset of spring in the young horse. This coincides with changes in day length, temperature, and progesterone concentrations. The change in growth, from slow to rapid in young horses has been associated with various forms of developmental orthopedic disease. The objective of this study was to distinguish associations between progesterone concentrations and other physiological and environmental measures from birth through 16 mo in young Thoroughbreds. Growth data and plasma samples were collected monthly from 3 annual crops of 20 foals. Plasma progesterone (P4) and insulin like growth factor one (IGF-I) concentrations were measured with previously validated radio immunoassay's (RIA). Progesterone concentrations were compared with day length, IGF-I and ADG using Spearman correlations. Concentrations of progesterone at birth (2.3 Â± 0.4 ng/mL) decreased within the first week of life to basal values (0.11 Â± 0.01 ng/mL) in colts and fillies. Progesterone in the geldings remained at baseline concentrations at all sample times. An abrupt increase in progesterone concentration was detected in fillies at a mean age of 385 Â± 6.4 d, weight 381 Â± 7.2 kg, and ADG 0.63 Â± 0.04 kg/d. Elevations in progesterone concentrations coincided with a measured day length of 13 Â± 0.1 hrs, and temperature of 15 Â± 1.7 Â°C. Positive associations were established between progesterone concentration day length (r = 0.59; P<0.0001), IGF-I (r = 0.25; P<0.01) and ADG (r = 0.34; P<0.0001). Day length IGF-I and ADG began to increase for both geldings and fillies at approximately 340 d of age, while progesterone started to increase at 385 Â± 6.4 d for the fillies only. From this it could be hypothesized that an increase in ADG combined with optimal environmental conditions, may be associated with the subsequent elevation in progesterone concentrations in fillies. The relationship between IGF-I, and various reproductive hormones has been studied in the adult horse, yet the associations between environmental factors, ADG, and progesterone concentrations demonstrated in growing yearlings further emphasizes the extensive changes occurring during this crucial developmental stage.
Master of Science

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Tzedaki, Aikaterini. "Into the sounding environment : a compositional approach." Thesis, De Montfort University, 2012. http://hdl.handle.net/2086/6529.

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The focus of the compositional approach presented in this folio is the sounding environment. The term sounding environment is used in this context to refer to the whole of our living experience in the world which we might register as relating to sound. It might include everything that is sounding, seemingly sounding, imagined sounding, remembered sounding, sensed as sounding, composed to sound. It includes thus the actual sound environment, all that is sensed or interpreted as sound and imaginary sounds. This dissertation accompanies the seven acousmatic and the two sound installation works included in the folio. It is divided into two parts. In the first part relevant ideas and theories both from the literature of electroacoustic music composition and soundscape composition are discussed while in the second the compositional approach to the sounding environment is presented as applied to the works.

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Miskimon, Amy K. "Healthy aging and the endocrine environment the association between the endocrine environment and body composition in postmenopausal women /." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009m/miskimon.pdf.

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Reynolds, Nicholas J. "Primary school creativity and composition in a professional level music software environment." Connect to thesis, 2001. http://repository.unimelb.edu.au/10187/1238.

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This paper provides an investigation into the use of professional level music software as a learning tool for creativity and composition in primary school children. The researcher believed that music and sound editing was under-used in schools and that children could: -work successfully with that type of software -work creatively with the software -benefit from its use. A small case study was used to expose the participants (eight children from Grades 3-6) to two professional level music software applications: Cakewalk Pro Audio 9 and Cool Edit 2000. The children explored the software and completed set tasks over a ten-week period. Data, in the form of the students’ work, taped copies of all sessions, interviews and researcher reflections, were analysed to present an understanding of the creative and compositional processes and products. In addition, all student pieces were recorded onto CD. The analysis of data suggests competent use of both software applications as well as satisfactory completion of set tasks. The data also indicate that the participants were able to operate at compositional levels beyond their age and musical skills and knowledge. Conclusions are drawn to suggest that, in this case, the use of this software has assisted the creative process and has allowed these children the opportunity to compose and construct pieces that could not have been constructed without the software. (For complete abstract open document)

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Adhitya, Sara. "Sonifying Urban Rhythms : towards the spatio-temporal composition of the urban environment." Paris, EHESS, 2013. http://www.theses.fr/2013EHES0079.

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Cette thèse s'intéresse à la composition de rythmes urbains générés par la conception et la planification urbaine. Elle reconnaît les limitations temporelles du plan d'urbanisme qui a tendance à être statique et singulier dans la composition de l'expérience urbaine. Ainsi, elle propose l'intégration du rythme dans le processus de conception urbaine, dans le but d'améliorer la qualité temporelle de l'espace urbain. Pour représenter ces rythmes tels qu'ils sont produits dans la conception graphique, nous proposons leur sonification. Un outil de sonification des plans d'urbanisme (l'outil SUM) a été développé, et permet la sonification de plusieurs couches de cartes le long d'un certain nombre de parcours d'intérêt. Un code sonore urbain a été développé dans le but de relier les paramètres graphiques urbains aux paramètres sonores. Nous avons pris comme cas d'étude la ville de Paris et avons appliqué cette stratégie à sa sonification, afin de produire un ensemble de cartes sonifiées de la ville dont la composition spatio-temporelle pourrait être "écoutée". Des questions temporelles concernant le mouvement humain, les infrastructures de transport, la distribution d'activité, la structuration de la forme urbaine et les éléments de conception, peuvent être représentées et entendues. Nous avons ensuite étudié le potentiel de l'outil SUM comme outil de conception et de planification. Ainsi, grâce à l'intégration de la sonification dans la conception et la planification urbaine, ce travail de recherche permet la représentation spatio-temporelle et la composition de la forme urbaine
This thesis is concerned with the composition of the urban rhythms generated by urban design and planning. It recognises the temporal limitations of the graphic urban masterplan, with its tendency of being static and singular in the composition of urban expérience. Thus it proposes the integration of rhythm into the urban design and planning process, with the aim to improve the temporal quality of urban design. In order to represent these urban rhythms, as designed in the graphic masterplan, we propose their sonification. A Soniﬁed Urban Masterplan (SUM) tool was developed, allowing the sonification of multiple layers of maps along a number of paths of interest. An urban sonic code was then developed in order to map the relevant graphic urban parameters into sound parameters. This sonification strategy was applied to the city of Paris as a case study, producing a sonified set of maps whose composition could be ‘listened’ to over time. Temporal issues concerning human movement, transport infrastructure, activity distribution, and the structuring of urban form and design elements could be represented and heard. We then investigated the potential of the SUM tool as a design and planning tool. Thus through the integration of sonification in urban design and planning, this thesis permits the spatio-temporal representation and composition of urban form

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Wise, Ben. "Community Composition of Nitrite Reductase Genes in an Acid Mine Drainage Environment." Thesis, University of Colorado at Denver, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10607867.

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High elevation, mountainous regions have a high concentration of mining activities and resulting acid mine drainage (AMD) that is typically acidic and often contains elevated concentrations of metals. The impacts of AMD on denitrifying microbial communities is not well understood, despite these organisms’ central role in the nitrogen cycle, contribution to greenhouse gas production, and potential to provide ecosystem services through the mitigation of nitrogen pollution. This study examined denitrifying microbes across four regions within the Iron Springs Mining District (13 sites over four time-points) located in Southwest Colorado at high elevation that receive AMD or naturally-occurring acid rock drainage (ARD). Denitrification functional gene sequences ( nirS and nirK coding for nitrite reductase) had a high number of observed OTUs (260 for nirS and 253 for nirK) and were observed at sites with pH as low as 3.2, dissolved oxygen as low as 1.0 mg/L, and metals >10 mg/L (including aluminum, iron, manganese, and zinc). A majority of the nirK and nirS OTUs (> 60%) were present in only one sampling region. Approximately 8% of the nirK and nirS OTUs had a more cosmopolitan distribution with presence in three or more regions. Phylogenetically related OTUs were found across sites with very different chemistry. The total nirS community structure was correlated to iron, conductivity, sodium, and calcium, which may suggest that these factors play an important role in shaping the nirS community. Overall, these findings improve upon our understanding of the potential for denitrification within an ecosystem impacted by AMD and provide a foundation for future research to understand the rates and physiology of these denitrifying organisms.

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Kinnear, Tyler. "Music in nature, nature in music : sounding the environment in contemporary composition." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61354.

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This thesis examines nature as both a concept and source material in contemporary music. Composers reinforce, revise, and challenge existing conceptualizations of nature through their engagement with natural settings, live or recorded environmental sounds, and/or non-sounding environmental information. How composers understand nature informs the ways in which they employ aspects of the physical world in their music. This study explores the interplay between nature-as-concept and nature-as-source-material in art-based walks, outdoor music, electroacoustic composition, and concert-hall pieces. Through analysis of works representative of these wide-ranging genres, this thesis offers a critical assessment of how nature is imagined in a contemporary musical context. The concept of a continuum is used as both a structural and theoretical tool in this study. A gradual transition from real-world encounters with nature to an abstracted experience of it is made over the course of the thesis. The works discussed in Chapter Two exist as lightly edited recordings made by artists during an outdoor walk/improvisation. The outdoor theatre piece considered in Chapter Three takes place at a lake and draws on that environment in several ways during a performance. The two electroacoustic compositions investigated in Chapter Four combine unmodified and modified nature sounds. The natural world is still present in the concert-hall works discussed in Chapter Five, but recorded nature sounds are combined with live instrumental music based on environmental properties and processes. In addition, this thesis traces four themes across works. These are technology, human presence, myth, and the transformation of the environment. The works under consideration demonstrate a range of approaches to composing with and conceptualizing nature. Some of the works comment on environmental issues, such as noise pollution and climate change. Others aim to drive understanding beyond the limits of human perception; that is, to open up new psychological spaces. In different ways, the works under focus illuminate the relationship between humans and the natural world. By stimulating discourse around how we think about nature, these pieces encourage critical thought regarding our place as humans in the physical environment.
Arts, Faculty of
Music, School of
Graduate

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Frisk, Ulrika. "Effects of high-altitude trekking on body composition." Thesis, Mittuniversitetet, Avdelningen för hälsovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-22219.

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Sojourns at high altitude are often accompanied by weight loss and changes in body composition. The aim was to study body composition before and after 40 days high-altitude exposure. The subjects were four women and six men, non-smoking, healthy and active students and a scientist from Mid Sweden University in Östersund with a mean (SD) age of 26 (10) years. All subjects volunteered for a six-week trek to the Mount Everest Base Camp via Rolwaling in Nepal. Before the sojourn subject’s height was 177 (10) cm and weight was 71.9 (10) kg. Body composition was measured with Lunar iDXA at the Swedish Winter Sports Research Centre in Östersund before and after the trek. Total body mass (SD) decreased from 71.8 (10.0) kg before to 69.7 (9.4) kg after the trek (P=0.00). Total fat mass decreased from 14.7 (5.9) kg to 13.8 (4.6) kg (P=0.01). Fat percent decreased from 21.6 (7.9) % to 21.0 (7.2) % (P=0.03). Total lean mass decreased from 54.0 (10.0) kg to 52.9 (9.7) kg (P=0.01). Bone mineral content was unchanged, 3.04 (0.5) kg before and 3.03 (0.5) after (P=0.13). Thus both total body mass and total lean mass had decreased after a six week trekking in Nepal.

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Brown, Sabrina L. "The effect of environment on seed composition of tofu and natto soybean cultivars." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4509.

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Thesis (M.S.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 22, 2007) Includes bibliographical references.

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Ralaiarisoa, Maryline. "Electronic properties of hybrid organic-inorganic perovskite films: effects of composition and environment." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20194.

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Der Schwerpunkt der vorliegenden Arbeit liegt in der Charakterisierung der elektronischen Eigenschaften von hybriden organisch-anorganischen Perowskit (HOIP)-Schichten während der Schichtbildung und in verschiedenen Umgebungen mittels Photoelektronenspektroskopie (PES). Insbesondere wird der Methylammonium-Blei-Iodid-Chlorid-Perowskit (MAPbI3-xClx) untersucht. Als erstes werden Änderungen in den elektronischen Eigenschaften, der Zusammensetzung, sowie der Kristallstruktur mittels PES, Flugzeit-Sekundärionenmassenspektrometrie, sowie Röntgendiffraktometrie mit streifendem Einfall analysiert. Die Resultate weisen auf die entscheidende Rolle von Chlor im texturierten Wachstum der Perowskitschicht hin. Die auskristallisierte Perowskitschicht weist eine stärkere n-Typ Eigenschaft auf, welche auf die Änderung der Zusammensetzung während der Schichtbildung zurückgeführt werden kann. Außerdem beweisen die Ergebnisse eindeutig die Ablagerung von Chlor an der Grenzfläche zwischen der Perowskitschicht und dem Substrat. Zweitens werden die separaten Einflüsse von Wasser, Sauerstoff, und Umgebungsluft auf die elektronischen Eigenschaften von MAPbI3-xClx-Schichtoberflächen untersucht. Bereits geringste Wassermengen ähnlich wie im Hochvakuum oder in inerter Umgebung können eine reversible Reduzierung der Austrittsarbeit hervorrufen. Höherer Wasserdampf-Partialdruck führt zu einer Verschiebung des Valenzbandmaximums (VBM) weit vom Fermi-Niveau, sowie zu einer Reduzierung der Austrittsarbeit. Im Gegensatz dazu führt eine Sauerstoffexposition zu einer Verschiebung des VBM in Richtung des Fermi-Niveaus und zu einer Steigerung der Austrittsarbeit. Analog kommt es zu einer Verschiebung von bis zu 0.6 eV bei einer Exposition gegenüber Umgebungsluft, was den vorwiegenden Einfluss von Sauerstoff demonstriert. Die vorliegenden Untersuchungen betonen den kritischen Einfluss der Schichtbildung, der Zusammensetzung, sowie der Umgebungsbedingungen auf die elektronischen Eigenschaften von HOIP.
The present thesis aims at characterizing the electronic properties of solution-processed hybrid organic-inorganic perovskites (HOIPs) in general, and the HOIP methyl ammonium (MA) lead iodide-chloride (MAPbI3-xClx) films, in particular, at different stages, namely from its formation to its degradation, by means of photoelectron spectroscopy (PES). Firstly, the formation of MAPbI3-xClx films upon thermal annealing is monitored by a combination of PES, time-of-flight secondary ion mass spectrometry, and grazing incidence X-ray diffraction for disclosing changes in electronic properties, film composition, and crystal structure, respectively. Overall, the results point to the essential mediating role of chlorine in the formation of a highly textured perovskite film. The film formation is accompanied by a change of composition which leads to the film becoming more n-type. The accumulation of chlorine at the interface between perovskite and the underlying substrate is also unambiguously revealed. Secondly, the separate effects of water and oxygen on the electronic properties of MAPbI3-xClx film surfaces are investigated by PES. Already low water exposure – as encountered in high vacuum or inert conditions – appears to reversibly impact the work function of the film surfaces. Water vapor in the mbar range induces a shift of the valence band maximum (VBM) away from the Fermi level accompanied by a decrease of the work function. In contrast, oxygen leads to a VBM shift towards the Fermi level and a concomitant increase of the work function. The effect of oxygen is found to predominate in ambient air with an associated shift of the energy levels by up to 0.6 eV. Overall, the findings contribute to an improved understanding of the structure-property relationships of HOIPs and emphasize the impact of least variation in the environmental conditions on the reproducibility of the electronic properties of perovskite materials.

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Belkhiri, Madeny. "Plasma out of thermodynamical equilibrium : influence of the plasma environment on atomic structure and collisional cross sections." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112268/document.

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Dans les plasmas chauds denses, la distribution spatiale des électrons libres et des ions peut affecter fortement la structure atomique. Pour tenir compte de ces effets, nous avons implémenter un potentiel plasma fond´ sur le modèle d’un gaz d’électron uniforme et sur une approche de type Thomas-Fermi dans le Flexible Atomic Code (FAC). Ce code a été utilisé, pour obtenir les énergies, les fonctions d’onde, et les taux radiative modiﬁés par l’environnement plasma. Dans des ions hydrogénoides, les résultats numériques ont été comparés avec succès à un calcul analytique basé sur la théorie des perturbations du premier ordre. Dans le cas des ions multi-électronique, on observe un décalage des niveaux, en accord avec d’autre calcul récent. Diverses méthodes pour les calculs de section efficace de collision sont examinées. L’inﬂuence de la densité du plasma sur ces sections est analysée en détail. Certaines expressions analytiques sont propos´es pour les ions hydrogénoides comme dans la limite où l’approximation de Born ou Lotz s’applique et sont comparés aux résultats numériques du code de FAC. Enﬁn, à partir de ce travail, nous étudions l’inﬂuence de l’environnement de plasma sur notre modèle collisionel-radiatif nommé -Foch-. En raison de cet environnement, la charge moyenne du plasma augmente, ceci est principalement due a l’abaissement du continuum. Nous observons également, le décalage des raies sur les spectres d’émission lié-lié. Un bon accord est trouvé entre notre travail et les données expérimentales sur un plasma de titane
In hot dense plasmas, the free-electron and ion spatial distribution may strongly affect the atomic structure. To account for such effects we have implemented a potential correction based on the uniform electron gas model and on a Thomas-Fermi Approach in the Flexible Atomic Code (FAC). This code has been applied to obtain energies, wave-functions and radiative rates modiﬁed by the plasma environment. In hydrogen-like ions, these numerical results have been successfully compared to an analytical calculation based on ﬁrst-order perturbation theory. In the case of multi-electron ions, we observe level crossings in agreement with another recent model calculation. Various methods for the collision cross-section calculations are reviewed. The inﬂuence of plasma environment on these cross-sections is analyzed in detail. Some analytical expressions are proposed for hydrogen-like ions in the limit where Born or Lotz approximations apply and are compared to the numerical results from the FAC code. Finally, from this work, we study the inﬂuence of the plasma environment on our collisional-radiative model so-called -Foch-. Because of this environment, the mean charge state of the ions increases. The line shift is observed on the bound-bound emission spectra. A good agreement is found between our work and experimental data on a Titanium plasma

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Clough, Elizabeth Anne, and n/a. "Factors Influencing Ant Assemblages and Ant Community Composition in a Sub-Tropical Suburban Environment." Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040719.141317.

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The main objective of this study was to examine the abundance and diversity of ants in suburban sites following vegetation removal or modification for development. This research examines the capacity of suburban sites to support ant diversity, which is dependent on the site characteristics and their surrounding environment. The study focused on 29 suburban garden and 3 suburban reserve sites on the Gold Coast, Queensland, Australia. This region, through continuing land development, undergoes ongoing habitat disturbance and modification. Ground-dwelling ants were collected by pitfall trapping in study sites over three summers between 1997 and 1999. In total, 28,512 ants from 60 species in 31 genera were collected. Garden sites that maintain vegetation structural diversity were found to be most similar to reserve sites in terms of ant community composition. These sites were highest in ant richness and diversity and contained particularly high proportions of specialized ant species. Sites in close proximity to remnants of native vegetation contained higher species diversity and a greater proportion of specialized ant species. The introduced tramp ant, Pheidole megacephala was found in 28 of the 32 sites and was found to significantly reduce ant species richness and diversity and displace the dominant ant Iridomyrmex sp. 1 in suburban environments. This ant poses a serious threat to the recovery of a diverse ant fauna to suburban environments. Ant community composition was shown to vary significantly among suburban sites. The ant functional groups commonly found in disturbed sites were abundant in open sites with little canopy cover in this study. Sites that provided vegetation structural diversity and areas of closed canopy supported similar functional groups to natural vegetation remnants. These results indicate that ant communities in suburban environments respond to disturbance in a similar manner to ant communities in tropical forests and rainforests. The dominance by functional groups and presence of specialized species may therefore be used as an indicator of disturbance and the restoration of suitable habitat in suburban sites. The presence of specialized species of ants in suburban garden sites and their clear preference for particular site characteristics indicate that these species utilize resources available in the suburban matrix. These results indicate that residential suburban sites are of value in the enhancement of ant diversity in fragmented landscapes and that they may provide supportive habitat to, and act as corridors between, vegetation fragments. In order to preserve biodiversity within suburban environments, landowners should be advised to retain as much existing vegetation within a site as possible. Clearing should be limited to that necessary to allow construction of dwellings and for safety. In addition, landowners should be encouraged to establish or maintain structurally diverse vegetation layers within sites in order to provide diverse microenvironments for fauna habitat.

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Sabatini, Benjamin J. "Chemical composition, thermodynamics, and recycling : the beginnings of predictive behavioral modeling for ancient copper-based systems." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:91a4426b-8232-4f85-a39b-69e6c01c327c.

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In their attempts to understand the unwritten past of human technology and progression, archaeologists have borrowed aspects of the natural sciences to answer big questions. In one such pursuit, fundamental aspects of the sciences have been employed towards the chemical compositional analysis of copper-based artifacts, often to simply classify which is bronze, brass, or pure copper, and to explain why they are significant in limited space and time. This thesis takes the variety of identified metal types and compositions from these analyses and builds the beginnings of an ambitious thermodynamic model based on the accepted premise of consistent and widespread recycling of ancient metals over time. Following the laws of thermodynamics, in systems at equilibrium, the model predicts the outcome of metal losses over the course of ancient pyrometallurgical processes from molten systems through both volatilization and oxidation using rigorous and established mathematics and theory. Elemental loss likelihoods are modeled for all binary copper-based metals, using activity coefficients, and ternary copper and zinc-based systems, with the excess Gibbs free energy, respectively. The calculations are performed using custom-written software designed to account for hundreds of thousands of compositional permutations after the method described by Redlich and Kister (1948). The results of these calculations are given as activity (binary) and isoactivity (ternary) contour lines. Quantified tables for the oxidation and volatilization of elements from a copper melt at 1200 ÂºC and 1 atm are also given as rough indicators of element loss in ancient pyrometallurgical systems. A proof of concept of the models viability is also provided for binary Cu-M and ternary Cu-M-Zn (M = Ag, As, Au, Bi, Co, Fe, Ni, Pb, Sb, Sn, Zn), Cu-Sn-Pb, and Cu-Sb-As systems from the Late Bronze Age to post-medieval periods in Britain, which is based on several substantial artifact chemical datasets. For each ternary system, the interaction parameters used for higher-order calculations from the fitted behavior of each contributing binary systems are provided. Comparison of the calculated models to available experimental system assessments, and to published archaeological chemical datasets, show that in both respects the proposed modeling of ancient copper-based metal losses works. And given the near ubiquity of ancient metal use around the world, the consistency in metal production and recycling technology, and the chemical analyses available, this preliminary model can be applied virtually anywhere the technology for smelting and recycling existed. In addition to loss modeling, this thesis has the additional offshoots of predicting ancient furnace conditions based on the calculated behavior of interacting metals, and of the controlling thermodynamic factors in the ancient calamine process.

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Casquilho, José Pinto. "Ecomosaico: indíces para diagnóstico de proporções de composição." Doctoral thesis, ISA/UTL, 1999. http://hdl.handle.net/10400.5/6932.

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Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia
Neste trabalho desenvolvem-se generalizações das funções de Shannon e de Simpson e estudam-se as suas propriedades, nomeadamente de caracterização de valores extremos. Aquelas funções, definidas desde o final dos anos quarenta, têm sido utilizadas em ecologia quantitativa como medidas (ou índices) de diversidade, equitabilidade e de dominância. Apresentam uma única solução crítica designada por solução equitativa, que é interpretável como um ponto de equilíbrio de um sistema dinâmico. Nos anos oitenta, aquelas funções foram introduzidas na Ecologia da Paisagem como medidas (ou índices) de avaliação da diversidade de mosaicos de paisagem. Essas medidas só introduzem informação de ordem corológica - proporções de ocupação do solo por k diferentes habitats - e ignoram qualquer caracterização de ordem topológica das componentes do mosaico, por exemplo relativa à biodiversidade característica dos diferentes elementos do mosaico de paisagem. Os desenvolvimentos que agora se apresentam visam contribuir para o preenchimento dessa lacuna. Nas generalizações estudadas o lugar das soluções de equilíbrio passa a depender da valorização atribuída a cada componente e, como consequência, a solução equitativa passa a ser apenas uma solução, dentro da variedade dos equilíbrios da generalização efectuada. As funções aqui apresentadas, que designamos por índices de diversidade sistémica e índices de valor sistémico do mosaico de paisagem permitem aprofundar o estudo das soluções de composição de um mosaico por k componentes, distintas e espacialmente intersubstituíveis. Daí a designação conjunta de índices para o diagnóstico de proporções do ecomosaico. Os resultados teóricos estabelecidos permitem controlo conceptual e analítico sobre as relações envolvidas na caracterização quantitativa das componentes do mosaico e do seu efeito no valor do índice. Ilustra-se computacionalmente o estudo feito, com um conjunto de simulações envolvendo 4 variáveis. Os índices são utilizados num exemplo relativo ao diagnóstico do mosaico de paisagem no Norte do concelho de Nisa colocado a propósito da expansão do eucaliptal (Eucalyptus globulus) no período 1970-1990. S5o apresentadas outras perspectivas com que estas funções podem vir a ser utilizadas noutros campos da Ecologia, em particular permitindo revisitar o paradigma diversidade-estabilidade---------------------------------------ABSTRACT - In this work we build generalizations of Shannon and Simpson's functions with emphasis on the study of extreme values and the characterization of extreme points. Shannon and Simpson's functions were defined in the late forties and have been used in quantitative ecology as measures (or indices) of diversity, evenness and dominance. They present a single critical solution, the equitable solution, which may be interpreted as the equilibrium point of a dynamic system. About the beginning of the eighties, those functions were introduced in Landscape Ecology, as measures (or indices) of diversity in landscape mosaics. Those measures just deal with information at the chorological level of landscape - the proportions of area of k different habitats - and ignore any characterization of the topological level of the elements of the mosaic, such as the biodiversity of the different ecosystems. This work makes a contribution toward solving that omission. In the generalizations we have studied the equilibrium points depend on the values attached to each element, and, as a consequence, the equitable solution is just a solution in the equilibrium manifold of the respective generalization. We name the new functions as systemic diversity indices and systemic value indices of the landscape mosaic, and they allow for the study of the relative composition of a mosaic with k distinct components, spatially interchangeable. We name globally those indices as indices for the diagnosis of proportions of composition of the ecomosaic. The theoretical results allow for conceptual and analytical control over the quantitative relationships involved in the value of the indices. We present simulations of the behavior of the new functions reaching a total of 4 variables in presence. The indices are used in an example relative to the diagnosis of a landscape mosaic at the North of Alentejo (Nisa), motivated by the expansion of Eucalyptus globulus in the region, in the period 1970-1990. We refer to other fields of Ecology where these functions could be used, in particular allowing revisiting the paradigm diversity-stability.

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Ndibewu, PP, MB Mgangira, N. Cingo, and RI McCrindle. "Metal and anion composition of two biopolymeric chemical stabilizers and toxicity risk implication for environment." Taylor & Francis, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001442.

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The objective of this study was to (1) measure the concentration of four anions (Cl-, F-, NO and SO ) and nine other elements (Al, Ba, Ca, K, Mg, Mn, Fe, Ni, and Si) in two nontraditional biopolymeric chemical stabilizers (EBCS1 and EBCS2), (2) investigate consequent environmental toxicity risk implications, and (3) create awareness regarding environmental health issues associated with metal concentration levels in enzyme-based chemical stabilizers that are now gaining widespread application in road construction and other concrete materials. Potential ecotoxicity impacts were studied on aqueous extracts of EBCS1 and EBCS2 using two thermodynamic properties models: the Pitzer–Mayorga model (calculation of the electrolyte activity coefficients) and the Millero–Pitzer model (calculation of the ionic activity coefficients). Results showed not only high concentrations of a variety of metal ions and inorganic anions, but also a significant variation between two chemical stabilizing mixtures. The mixture (EBCS2) with the lower pH value was richer in all the cationic and anionic species than (EBCS1). Sulfate ( ) concentrations were found to be higher in EBCS2 than in EBCS1. There was no correlation between electrolyte activity and presence of the ionic species, which may be linked to a possible high ionic environmental activity. The concentrations of trace metals found (Mn, Fe, and Ni) were low compared to those of earth metals (Ba, Ca, K, and Mg). The metal concentrations were higher in EBCS1 than in EBCS2. Data suggest that specific studies are needed to establish “zero” permissible metal ecotoxicity values for elements and anions in any such strong polyelectrolytic enzyme-based chemical stabilizers.

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Smith, Matt. "Towards an intelligent learning environment for melody composition through formalisation of Narmour's implication-realisation model." Thesis, Open University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336976.

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Brown, Jillian. "Bacterial community composition, TCE degradation, isotopic fractionation and toxicity of a TCE contaminated aquifer." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=33520.

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30

Wolf, Brian Christopher. "Environmental crime and justice : the organizational composition of corporate noncompliance /." view abstract or download file of text, 2005. http://wwwlib.umi.com/cr/uoregon/fullcit?p3181136.

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Thesis (Ph. D.)--University of Oregon, 2005.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 140-148). Also available for download via the World Wide Web; free to University of Oregon users.

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31

Björklund, Johan. "Thermodynamic Aspects on Inclusion Composition and Oxygen Activity during Ladle Treatment." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4673.

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Two industrial studies and one set of lab scale trials have been done. In addition, a theoretical study has been done. The main focus has been on non metallic inclusion composition during the ladle refining operation in industrial steel production. Sampling has been done together with careful inclusion determination. The inclusion composition is related to different variables. In the industrial trials samples have been taken at different steps during the ladle refining period. Steel and slag composition as well as temperature and oxygen activity have been determined. The thesis is based on five supplements with different major objectives, all related to the inclusion composition. The equilibrium top slag-steel bulk and inclusions-steel bulk were investigated by comparison between calculated and measured oxygen activity values. The oxygen activity and relation to temperature has also been discussed as well as oxygen activity and temperature gradients. The effect of vacuum pressure on inclusion composition has been evaluated in a theoretical study as well as lab scale trials. The inclusion composition has been studied during the industrial ladle treatment process. The inclusion composition was related to top slag composition and other parameters during ladle treatment. The major findings in the thesis are the lack of equilibrium conditions with respect to top-slag and steel bulk before vacuum treatment. The inclusions have been found to be closer to equilibrium with the steel bulk. Al/Al2O3 equilibrium has been found to control the oxygen activity after Al-deoxidation. Evaluation of inclusion composition during the ladle refining has revealed that the majority of the inclusions showed a continuous composition change throughout the ladle refining process, from high Al2O3, via MgO-spinel to finally complex types rich in CaO and Al2O3. The final inclusion composition after vacuum treatment was found to be close to the top slag composition. Vacuum pressure has been found to have a theoretical effect on inclusion composition at very low pressures.
QC 20100712

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Kanbe, Yuichi. "Control of Alloy Composition and Evaluation of Macro Inclusions during Alloy Making." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-27773.

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In order to obtain a good performance and predict the properties of alloys, it is necessary to control the contents of alloying elements and to evaluate a largest inclusion in the product. Thus, improved techniques for both control of alloy elements and evaluation of the large inclusion in products will enable us to provide better qualities of the final products. In the case of one Ni alloy, (NW2201, >99 mass%Ni), the precise control technique of Mg content is important to obtain a good hot-workability. Hereby, the slag/metal reaction experiments in a laboratory have been carried out at 1873 K, so that the equilibrium Mg content and kinetic behavior can be understood. More addition of Al in the melt as well as higher CaO/Al2O3 value of slag resulted in higher amount of Mg content in Ni. For the same conditions of Al content and slag composition, the mass transfer coefficient of Mg in molten Ni was determined as 0.0175 cm/s. By applying several countermeasures regarding the equilibrium and kinetic process to the plant trials, the value of the standard deviation for the Mg content in an alloy was decreased till 0.003 from 0.007 mass%. The size measurements of largest inclusions in the various alloys (an Fe-10mass%Ni alloy, 17CrMo4 of low-C steel and 304 stainless steel) were carried out by using statistics of extreme values (SEV). In order to improve the prediction accuracy of this method, three dimensional (3D) observations were applied after electrolytic extraction. In addition, the relationship of extreme value distribution (EVD) in the different stages of the production processes was studied. This was done to predict the largest inclusion in the products at an early stage of the process. A comparison of EVDs for single Al2O3 inclusion particles obtained by 2D and 3D observations has clarified that 3D observations result in more accurate EVD because of the absence of pores. Also, it was found that EVD of clusters were larger than that of single particles. In addition, when applying SEV to sulfide inclusions with various morphologies, especially for elongated sulfides, the real maximum sizes of them were able to be measured by 3D observations. Geometrical considerations of these particles clarified the possibility of an appearance of the real maximum inclusion sizes on a cross section to be low. The EVDs of deoxidation products in 304 stainless steel showed good agreement between the molten steel and slab samples of the same heat. Furthermore, the EVD of fractured inclusion lengths in the rolled steel were estimated from the initial sizes of undeformed inclusions which were equivalent with fragmented inclusions. On the other hand, from the viewpoint of inclusion width, EVD obtained from perpendicular cross section of strips was found to be useful to predict the largest inclusion in the final product with less time consumption compared to a slab sample. In summary, it can be concluded that the improvement of the techniques by this study has enabled to precisely control of alloy compositions as well as to evaluate the largest inclusion size in them more accurately and at an earlier stage of the production process.
QC 20101222

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Olovsson, Weine. "Influence of Global Composition and Local Environment on the Spectroscopic and Magnetic Properties of Metallic Alloys." Doctoral thesis, Uppsala University, Department of Physics, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5823.

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Theoretical investigations of spectroscopic and magnetic properties of metallic systems in the bulk, as well as in nanostructured materials, have been performed within the density functional theory. The major part of the present work studies the differences between binding energies of electrons tightly bound to the atoms, the so-called core electrons (in contrast with the valence electrons), that is, core-level binding energy shift (CLS).

By comparison between corresponding elemental core-levels for atoms situated in different chemical environments we obtain fundamental understanding of bonding properties of materials. The method of choice was the complete screening picture, which includes initial and final state effects on the same footing. The usefulness of CLS stems from that it is sensitive to differences in the chemical environment of an atom, which can be affected on one hand by the global composition of e.g. disordered materials, surfaces and interfaces, and on the other hand by the very local environment around an atom. Here CLSs have been obtained for both components in the fcc random alloys AgPd, CuPd, CuNi, CuPt, CuAu, PdAu, NiPd and NiPt. Moreover the model was extended to the Auger kinetic energy shift for the LMM Auger transition in AgPd alloys. Studies were also applied to the near surface and interface regions of PdMn nano structures on Pd(100), thin CuPd and AgPd films on inert Ru(0001), and at interfaces. The disorder broadening on CLS due to local environment effects was calculated in selected alloys.

A part of the thesis concern investigations related to the magnetic ordering in Invar alloys, including the influence of local environment effects. A study was made for the dependence of effective exchange parameter on the electron concentration, volume and local chemical composition.

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Schweitzer, Barbara Christina [Verfasser]. "The effect of the extracellular environment on the composition and function of synapses / Barbara Christina Schweitzer." Magdeburg : Universitätsbibliothek, 2015. http://d-nb.info/109830697X/34.

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Klie, Torsten. "Policy refinement using automatic composition of management web services in a policy based autonomic communications environment." Berlin Logos-Verl, 2008. http://d-nb.info/992551609/04.

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Champagne, Alex Michael. "Lipid composition and molecular interactions in the stratum corneum of birds in response to differences in environment." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1400083589.

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Shetty, Rashmi S. "An event driven single game solution for resource allocation in a multi-crisis environment." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000533.

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Radoman-Shaw, Brandon G. "Exposure of Basaltic Materials to Venus Surface Conditions using the Glenn Extreme Environment Rig (GEER)." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1557312457308105.

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Collet, Remo. "On the Chemical Composition of Metal-Poor Stars : Impact of Stellar Granulation and Departures from Local Thermodynamic Equilibrium on the Formation of Spectral Lines." Doctoral thesis, Uppsala University, Department of Astronomy and Space Physics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7121.

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The information about the chemical compositions of stars is encoded in their spectra. Accurate determinations of these compositions are crucial for our understanding of stellar nucleosynthesis and Galactic chemical evolution. The determination of elemental abundances in stars requires models for the stellar atmospheres and the processes of line formation. Nearly all spectroscopic analyses of late-type stars carried out today are based on one-dimensional (1D), hydrostatic model atmospheres and on the assumption of local thermodynamic equilibrium (LTE). This approach can lead to large systematic errors in the predicted stellar atmospheric structures and line-strengths, and, hence, in the derived stellar abundances. In this thesis, examples of departures from LTE and from hydrostatic equilibrium are explored. The effects of background line opacities (line-blocking) due to atomic lines on the statistical equilibrium of Fe are investigated in late-type stars. Accounting for this line opacity is important at solar metallicity, where line-blocking significantly reduces the rates of radiatively induced ionizations of Fe. On the contrary, the effects of line-blocking in metal-poor stars are insignificant. In metal-poor stars, the dominant uncertainty in the statistical equilibrium of Fe is the treatment of inelastic H+Fe collisions. Substantial departures of Fe abundances from LTE are found at low metallicities: about 0.3 dex with efficient H+Fe collisions and about 0.5 dex without. The impact of three-dimensional (3D) hydrodynamical model atmospheres on line formation in red giant stars is also investigated. Inhomogeneities and correlated velocity fields in 3D models and differences between the mean 3D stratifications and corresponding 1D model atmospheres can significantly affect the predicted line strengths and derived abundances, in particular at very low metallicities. In LTE, the differences between 3D and 1D abundances of C, N, and O derived from CH, NH, and OH weak low-excitation lines are in the range -0.5 dex to -1.0 dex at [Fe/H]=-3. Large negative corrections (about -0.8 dex) are also found in LTE for weak low-excitation neutral Fe lines. We also investigate the impact of 3D hydrodynamical model stellar atmospheres on the determination of elemental abundances in the carbon-rich, hyper iron-poor stars HE 0107-5240 and HE 1327-2326. The lower temperatures of the line-forming regions of the 3D models compared with 1D models cause changes in the predicted spectral line strengths. In particular we find the 3D abundances of C, N, and O to be lower by about -0.8 dex (or more) than estimated from a 1D analysis. The 3D abundance of Fe is decreased but only by -0.2 dex. Departures from LTE for Fe might actually be very large for these stars and dominate over the effects due to granulation.

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40

Dooley, James. "Sounding the environment : research through composition exploring the interplay of space and place in musical and installation works." Thesis, Birmingham City University, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.691367.

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The relationship between sound and the environment is complex. How we present musical or sound works has a profound effect on the way we perceive them, and the way we perceive the performance or installation environment. Composers and sound artists can exploit and explore this fundamental relationship between sound and environment through creative works. From utilising a place's acoustic properties to exploring its cultural significance, the artist has access to a palette of resources to transform the audience's conceptualisation of sound and environment. When creating a work that explores a sound-environment relationship, it is important that we then ask how the work can engage with its performance or installation environment, how it can be adapted to different environments, and how it can transform a space into place. A range of approaches exploring and integrating sound-environment relationships into musical and sound works are investigated in this thesis. A practice-based methodology has been adopted, where I have iteratively contextualised and critically reflected upon my own creative practice. This has produced a portfolio of creative works, software and a written commentary. Emerging from the portfolio and works examined throughout this research, a typology of sound-environment relationships is proposed. In conclusion, an assessment is given of how the typology and portfolio each address the research questions. General conclusions are then presented, further discussing how to approach works with sound-environment relationships and suggestions for their possible applications. Finally, potential research beyond this thesis is also discussed.

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Martinez, Ubeda Ana Isabel. "Effect of composition variation and service environment on the long term ageing of Type 316H austenitic stainless steels." Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.723485.

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Lundin, Linnéa. "Interpretation of the P-T-XCO2 environment during metamorphism of carbonates, central Utö, Stockholm archipelago." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93279.

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This thesis attempts to interpret the metamorphic condition and fluid composition experienced by metacarbonates on Utö, located in the south-eastern parts of the Stockholm archipelago. Utö is a part of the Svecofennian domain, and the area Bergslagen, that has hosted several mines over the last millennia. The bedrock in this area has been dated by the U-Pb technique to 1.90-1.87 Ga, placing it in the Paleoproterozoic era (Allen et al. 1996, Lundström et al. 1998). The rocks, of the studied area on the island of Utö, are mainly metacarbonates with a varying purity and thin layers of volcanic ash. These rocks become more felsic towards the north-western coast as the layers of felsic ash become more dominant. To determine the P-T-XCO2 of metamorphism, metacarbonates were examined, in the field, in thin sections and mineral chemistry was determined by SEM analysis. Three samples were collected along a 1km transect, along which the assemblage calcite + dolomite + quartz + tremolite + diopside was observed. Petrographic and SEM analysis were performed to gather chemical data from coexisting calcite and dolomite in order to calculate temperature using the calcite-dolomite geothermometer. Chemical data from the SEM analysis were also run with AX and THERMOCALC together with pressure data received from a study by Engström (2011) of the adjacent island, Persholmen, to generate a T- XCO2 diagram. Pressure was estimated to 3.1 +/- 1.3 kbars, temperature calculated to 442°C 30°C and XCO2 to range from 0,00067-0,0038 with the standard deviation taken in to account. These results record equilibration with a CO2-bearing hydrous fluid at greenschist facies conditions.
Metamorphic map of Sweden

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Clarkson, Christopher Raymond. "The effect of coal composition, moisture content, and pore volume distribution upon single and binary gas equilibrium and nonequilibrium adsorption : implications for gas content determination." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0008/NQ34543.pdf.

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Meier, Cristian L. "Examining geographic, neighborhood composition, and household factors associated with primary food store selection." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6207.

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Healthy food store availability is by no means equitable, that is supermarkets and supercenters are not located nearby for certain populations. Shopping at healthy food stores is important, as dietary intake is associated with adverse health outcomes, which disproportionally affects racial and ethnic minorities. Yet rural areas and disadvantaged neighborhoods—low income or predominantly racial/ethnic minority compositions—have few healthy food store options available near home. Thus residents must use more resources to access them or make do with what is available close by. However, little is known about the characteristics associated with shopping at healthy food stores or shopping near home. Thus the purpose of this study was to examine predictors of shopping at healthy food stores and shopping within increasing distances from home. This study used data from the USDA’s National Household Food Acquisition and Purchase Survey (FoodAPS) which asked about household food purchasing behaviors. The FoodAPS data set was used to conduct a secondary data analysis of US households (N = 4,826) that was a nationally representative sample. A series of multilevel logistic regression models were conducted to examine the four research questions guiding this study. The four questions examined predictors of: (1) shopping at a healthy food store, (2) shopping at a healthy food store among rural and suburban respondents, (3) shopping within increasing distances from home, and (4) shopping within increasing distances from home among healthy food store shoppers. Results indicated that Hispanic/Latino and other racial/ethnic minority, the distance of travel to the store, and the number of food stores available within 5.0 miles were negatively associated with shopping at a healthy food store. In addition, among rural and urban/suburban respondents had differing predictors of shopping at a healthy food store. Predictors of shopping within increasing distances from home included car to store and living in rural areas. Respondents who used a car as the transportation to the store were less likely to shop within 2.0 miles of home or less. Not surprisingly, rural respondents were also less likely to shop within 5.0 miles of home or less. Several control variables were significant predictors of shopping within increasing distances from home which were unexpected. Results in some instances were surprising and contradictory to findings from past studies. Thus these results are discussed and are compared and contrasted with past studies. The results of this study have practice implications for social workers. Social work practitioners working with individuals can advocate for improving client access in their communities by improving and introducing programming whose goal is to connect people to food resources. Social workers engaged in policy efforts can work at the local, state, and national levels by working in multidisciplinary groups to improve existing programs and prioritize funding that improves issues of equality. While this study examined predictors among a nationally representative sample, it is important for future research to look at differences specifically among age groups, racial and ethnic minorities, and rural residents.

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Robinson, Jon. "The exploration and design of a language and middleware architecture dedicated to service composition in a pervasive computing environment." Thesis, University of Sussex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429880.

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Acheampong, Emmanuel [Verfasser], and John Michael A. [Akademischer Betreuer] St. "Copepod production : The interplay between abiotic environment, prey biochemical composition and consumers' requirements / Emmanuel Acheampong. Betreuer: Michael A. St. John." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2011. http://d-nb.info/1020458666/34.

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Matsson, Sanna. "Optimal physical and chemical environment for vegetative gametophyte culture of Saccharina latissima : - with emphasis on nutrient composition and light quality." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21422.

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The production of sporelings is a bottle-neck when cultivating Saccharina latissima. Establishing a vegetative gametophyte stocks gives a constant supply of healthy sporelings, enabling a year-round cultivation independent of the availability of natural spores. Finding optimal conditions for vegetative growth of gametophytes are of importance to produce mass quantities of sporelings. In the present study, it was desirable to establish optimal fysical and chemical environments for vegetative gametophyte culture of S. latissima which can be used in large scale cultivation systems. This were examined by five different experiments evaluating the effect of nutrient composition and light quality on growth and development on S. latissima gametophytes. The two most commonly used media when cultivating laminaria; Provasoli’s Enriched seawater (PES) and Guillard’s f/2 medium (f/2), were examined. The nutrient compisiton were examined through the addition of nitrogen (N) and phosphorous (P) in different concentrations and ratios to steralized seawater (SSW). The growth hormones kinetin (KIN) and Indole-3-acetic acid (IAA) was added in different concentrations to PES in a concentration gradient and the seaweed extract AlgeaFert was added in different concentrations to half strength PES (PES/2) due to its assumed presence of several plant growth substances. The growth of gametophytes was compared under red LED lights preventing fertility and under white florescence lights. White light contains blue wavelengths, thereby inducing fertility. Altering the nutrient ratio can be used to manipulate gametophyte cultures to grow vegetatively. The experiments conducted in white light therefore had a gradient of N:P ratios to evaluate the effect on fertility. The experiments revealed the growth of S. latissima gametophytes to be highly dependent on the chemical composition of the medium it was grown in and it had a significantly higher growth in PES compared to f/2. An increased growth was strongly affected by the presence of chelating agents, an increased concentration of N and P and a low ratio between them, and the addition of a low concentration of seaweed extract. The present study demonstrated that an alternation of light quality from red LED light to warm-white fluorescence light gave a significantly increased growth of S. latissima gametophytes. Since none of the treatments in this study resulted in fertility it cannot be concluded which treatments that inhibit fertilization and promote vegetative growth.

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Roa, Pascuali Carmen Liliana. "Mesoscale structure and dynamics of the tropical tuna's associated-environment in the Indian and the Eastern Pacific Oceans : comparative approach." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTS030.

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Le présent travail a pour but d'étudier la structuration à méso-échelle (de quelques kilomètres à quelques centaines de kilomètres) de l'environnement des trois espèces majeures de thons tropicaux, l'Albacore (Thunnus Albacares;YFT), le Listao (Katsuwonus Pelamis;SKJ) et le thon obèse (Thunnus obesus;BET), pêchés à la seine tournante dans les océans Indien et Pacifique Tropical Est (EPO), en fonction de leur tailles et leur distribution. Ces trois espèces représentent 20% et 13% des prises mondiales respectivement dans les 2 océans. Les prises par callées uniques sont utilisées pour évaluer séparément les caractéristiques environnementales de leur zones de pêche pour trois modes de pêche: sur banc libre (FS), objets flottants naturels (LOG) et sur dispositifs de concentration du poisson (DCP), ceci pour plusieurs tailles d'individus. Préalablement aux analyses, une double méthode statistique et d'expertise est utilisée pour la détection et la classification des fronts thermiques, utilisable à l'échelle des bassins océaniques, tandis que les tourbillons de méso-échelle, cycloniques et anticycloniques sont détectés par la méthode des winding angle. Les distances des prises à ces structures sont ensuite calculées. Nous trouvons que les fronts intenses concernent surtout les régions côtières et les fronts faibles l'océan du large, ce qui permet de prendre en compte des mécanismes de frontogénèse différents pouvant avoir un pouvoir attractif différemment sur les thons. En plus des composantes de méso-échelle, les variables classiques de l’environnement, les variables temporelles et celles liées à la pêche sont utilisées. Nous utilisons le modèle bayésien "Boosted Regression Tree” (BRT) suivant un schéma en 3 phases pour chaque océan pour explorer les réponses du niveau de prise pour chaque espèce et trois modes de pêche. La dominance relative est également explorée pour les prises sur FADs (O. indien) et FADs et FS (EPO) et montre des résultats similaires au niveau de prise. Tous les modèles BRT montrent que le niveau de prise est davantage relié à la variabilité environnementale pour les bancs libres que pour les FADs. Nous mettons en évidence pour la première fois l'importance des structures de méso-échelle sur la définition des habitats des thons, ce qui est confirmé par les faibles niveaux d'explication obtenus par les modèles de type « random », notamment dans l'océan indien. Pour les deux océans, les petits individus sont fortement associés aux tourbillons (distances <200km) tandis que les plus gros individus sont situés plus loin des tourbillons. Une faible influence des fronts thermiques est constatée dans l'Océan Indien tandis que l'opposé est trouvé pour le Pacifique, sauf dans les régions côtières où les forts fronts ont une influence importante. Différentes conditions environnementales sont observées dans des régions précises du Pacifique comme les upwellings côtiers, la bande équatoriale et le dôme du Costa Rica. Contrairement à l'Océan Indien, où les zones de pêches sont relativement homogènes en terme de température et chlorophylle de surface, ces deux paramètres influencent nettement plus la distribution des thons dans le Pacifique. Dans l'Océan Indien, le pourcentage total des contributions relatives par catégories de variables est de 34 % pour les variables de méso-échelle, de 39 % pour les variables classiques et de 27 % pour les autres (temporelles et pêche). Pour le Pacifique Est, même si la méso-échelle est importante (37%) les autres variables dominent en contribution relative (55 % et 8%).Mots clé : Thons tropicaux, taille, Océan Indien, Océan Pacifique Est, environnement, méso-échelle, senne tournante, modes de pêche
This study provides an approach to the comprehension of the mesoscale structure in the habitat patterns of three major tropical tunas species, yellowfin (Thunnus albacares; YFT), skipjack (Katsuwonus pelamis; SKJ) and bigeye (Thunnus obesus: BET). These species, mainly caught by the purse seiner's fishery worldwide, represent 20% and 13% of the world total production for the Indian and the Eastern Pacific oceans respectively. Single set records from this fishing gear in both, the Indian and in the Eastern Pacific oceans, were used to separately evaluate the environmental characteristics of their fishing grounds for three fishing modes: free school (FS), log (LOG) and fish aggregated devices (FADs) and several individual sizes. Prior to the analyses, a statistical expert-based method was applied to detect and classify thermal fronts at basin scale whereas the anticyclonic and cyclonic eddies are detected, based on the winding angle method. The distances of the catch positions from these structures were then calculated. We found that strong fronts are mostly found in coastal regions and weak fronts in the open ocean. This allows the consideration of the frontal intensity helps to spatially differentiate mechanisms of frontogenesis than may attract tunas. In addition to these mesoscale components, classic, temporal and fishery-related variables were added to describe the fishing environment. We used the Boosted Regression Tree (BRT) method to create a three step modeling scheme for each study area in order to explore the responses of the catch level and size for the different fishing modes, also considering the effect of randomly distributed catch positions, in order to separately estimate the mesoscale effects. The relative dominance of each species is also explored and globally shows similar results than for the catch level. All BRT models show that the catch level was better explained by the environment for free school (FS) than for FADs fishing modes and that the differences in distribution were more important among fish-sizes than among species. We quantify for the first time the strong influence of the mesoscale in determining tuna's habitat, confirmed by the poor explanation obtained in all random models, mainly for the IO. For both oceans, small individual were strongly related with the proximity to mesoscale eddies (<200 km) whereas the larger individuals area found at larger distances. A low influence of mesoscale fronts was found mainly for the Indian ocean whereas the opposite pattern was observed for the EPO, except in the coastal regions where strong fronts become important. Different environmental conditions were observed in well defined sub-regions as the coastal upwelling, the equatorial tongue, and the Costa Rica Dome. Contrarily to the Indian ocean were the fishing grounds are relatively homogeneous in term of Sea Surface Temperature and chlorophyll concentration, these two parameters highly influence the tuna distribution in the EPO. In the Indian Ocean, the total percentages of relative contribution by category of variables for all models were 34% for the mesoscale, 39% for the classical variables and 27% for others (temporal and fisheries related). For the Eastern Pacific, even if mesoscale remains important (37%), the most relevant ones were the classical variables with 55% of the total relative contribution (8% for others). Key word: Tropical tunas, Indian Ocean, Eastern Pacific Ocean, mesoscale, purse seiner, species, fish-size, fishing mode

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Larsson, Anna. "Evaluation of artificial habitats for saproxylic oak invertebrates: Effects of substrate, composition and distance from dispersal source." Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11689.

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Saproxylic species living in old hollow trees have low dispersal rate. Many of the species are threatened since their micro habitats are rare. To prevent some of these species from going extinct their habitats have to have the right management. In some areas artificial environment could be a solution. The aim of this study was to investigate if the insects that are dependent on tree cavities with wood mould would colonize an artificially created habitat: large wooden boxes filled with artificial wood mould placed on tree trunks. The boxes were filled with substrates like oak saw dust, oak leaves, dead hens, hen excrements, medicago (Medicago falcata flour) or potatoes. Over three years, 136 species and 10 380 specimens were caught in 47 boxes. The groups classified as specialists were in general statistically significant more often than groups classified as generalists. Dead hen was the substrate with the highest number of species, although differences were small. In conclusion, a large number of species, including red listed ones and saproxylic specialists used the boxes. A dead hen in the box gave some extra species and 1800 meters was too long for some of the species to disperse. Hence, the prospects for using artificial environments are good especially to reduce habitat availability gaps in time and space.

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Keinonen, Marja. "The isotopic composition of lead in man and the environment in Finland isotope ratios of lead as indicators of pollutant source /." Helsinki, Finland : University of Helsinki, Dept. of Radiochemistry, 1989. http://catalog.hathitrust.org/api/volumes/oclc/26521537.html.

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Dissertations / Theses on the topic 'Equilibrium composition of the environment'

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