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11	Investigação do processo de foto-ionização associativa em situações com baixa dimensão / Photoassociative ionization in situations with low dimensions Paiva, Rafael Rothganger de 17 February 2009 (has links) Neste trabalho estudamos o processo de foto-ionização associativa(PAI) em uma amostra fria de átomos de sódio com o objetivo entender os efeitos dos estados repulsivos e dimensão da colisão. Realizamos experimentos de PAI com duas cores em uma armadilha magneto-óptica adicionando um feixe de prova com intensidade, frequências e polarização ajustáveis. O formato dos átomos aprisionados também foi uma das variáveis no estudo da PAI. Para os átomos em formação esférica, observamos uma mudança marcante no comportamento da constante de taxa de formação da foto-ionização associativa(K) para um determinado domínio de frequências, e essa mudança no comportamento pode ser atribuída a participação de estados moleculares repulsivos na PAI e a formação de um possível cruzamento evitado entre os níveis moleculares. No atomotron ,armadilha atômica em forma de anel, variamos a polarização do laser de prova e constatamos que a razão entre K das polarizações paralela e perpendicular ao movimento dos átomos é igual a 4. Uma comparação entre K do atomotron e o da armadilha esférica em função da intensidade do feixe de prova, nos mostrou uma diferença no comportamento e no valor da constante de taxa. / Photoassociative ionization (PAI) in a cold sample of sodium atoms was the main subject of our studies as a way to understand the effects of repulsive states and collision dimensions. Two-color PAI experiment were preformed in a magneto-optical trap (MOT) trough the addition of a probe laser beam, the intensity, polarization and frequency of that probe laser were tunable. The shape of the trapped atoms also could be changed. In a spherical shape MOT, we observed a marked change in the PAI rate constant (K) for a definite frequency range, and that change can be attributed to the influence of repulsive molecular states and the a possible formation of an avoided crossing between molecular levels. In atomotron, ring shaped mot, we changed the polarization of the probe beam, and saw that the ratio between K for a polarization parallel to the atoms motion and a perpendicular one is 4. Comparing the K as a function of the intensity between a spherical shaped mot and atomotron showed us a difference in the behavior and the value of the rate constant. Armadilha Magneto-óptica Atomic collisions Atomotron Atomotron Avoided crossing Colisões atômicas Cruzamento evitado Estado molecular repulsivo Foto-ionização associativa Magneto-Optical Trap Photo associative ionization Repulsive molecular state
12	Valoração econômica do serviço de redução de sedimentos das florestas da bacia hidrográfica do Canal do Panamá / Economic valuation of the impact of the Panama Canal basin forests in sediment reduction Núñez, Eustorgio Jaén 25 July 2011 (has links) O processo de sedimentação e assoreamento reduz a profundidade e a capacidade dos lagos de armazenamento de água do Canal do Panamá, obrigando a realizar dragagens periódicas que aumentam os custos de operação. Esses processos são acelerados pela perda de cobertura florestal na bacia. O presente estudo teve por objetivo estimar o valor econômico associado à redução de sedimentos na floresta da bacia do Canal, através do método de custo evitado de dragagem. O efeito físico da cobertura florestal sobre a redução de sedimentos foi estimado a través de regressão linear de dados biofísicos de sete microbacias que dispõem de medições de produção de sedimentos: Chagres, Pequení, Boquerón, Gatún, Trinidad, Cirí Grande e Caño Quebrado. Os resultados mostram que cada hectare de floresta nesta área reduz em 14,76 t.ano-1 de sedimentos em suspensão. Adicionando sedimentos de fundo isso corresponde a 14,32 t.ha-1.ano-1 e a um valor econômico de USD 197,40 por hectare por ano. Concluiu-se que as florestas contribuem significativamente para mitigar o processo de assoreamento dos lagos de armazenamento de água para o funcionamento do Canal do Panamá, e essa contribuição pode ser valorada em USD 39.640.091 por ano, para toda a floresta da bacia. / Sedimentation and siltation reduce the lakes depth and capacity to hold water in the Panama Canal, requiring periodic dredging which increases the operation costs. These processes are accelerated by the loss of forests that cover the basin. This studys objective is to estimate the economic value associated with reduction of sediments in the Canal basin, based on the method of avoided dredging cost. The physical effect of forest on sediment reduction was estimated through linear regression of biophysical data for seven watersheds that have measurements of sediments yield: Chagres, Pequení, Boquerón, Gatún, Trinidad, Cirí Grande and Caño Quebrado. These results shows that each hectare of forest in this area reduces the sediments in suspension. By adding sediments from the bottom of the riverbed, this corresponds to 14.32 m3.ha- 1.year-1 and to an economic value of USD 197.40 per hectare per year. It was concluded that forests contribute significantly to mitigate the process of siltation of lakes water storage for the operation of the Panama Canal, and this contribution may be valued at USD 39,640,091 per year for the entire basin forest. Avoided Cost. Bacia hidrográfica Canal do Panamá Custo de operações Deposição de sedimentos Florestas - Impactos físicos Forest covering Matas ciliares Panama Canal Sedimentation Sedimentologia Valor (Economia). Watersheds
13	Valoração econômica do serviço de redução de sedimentos das florestas da bacia hidrográfica do Canal do Panamá / Economic valuation of the impact of the Panama Canal basin forests in sediment reduction Eustorgio Jaén Núñez 25 July 2011 (has links) O processo de sedimentação e assoreamento reduz a profundidade e a capacidade dos lagos de armazenamento de água do Canal do Panamá, obrigando a realizar dragagens periódicas que aumentam os custos de operação. Esses processos são acelerados pela perda de cobertura florestal na bacia. O presente estudo teve por objetivo estimar o valor econômico associado à redução de sedimentos na floresta da bacia do Canal, através do método de custo evitado de dragagem. O efeito físico da cobertura florestal sobre a redução de sedimentos foi estimado a través de regressão linear de dados biofísicos de sete microbacias que dispõem de medições de produção de sedimentos: Chagres, Pequení, Boquerón, Gatún, Trinidad, Cirí Grande e Caño Quebrado. Os resultados mostram que cada hectare de floresta nesta área reduz em 14,76 t.ano-1 de sedimentos em suspensão. Adicionando sedimentos de fundo isso corresponde a 14,32 t.ha-1.ano-1 e a um valor econômico de USD 197,40 por hectare por ano. Concluiu-se que as florestas contribuem significativamente para mitigar o processo de assoreamento dos lagos de armazenamento de água para o funcionamento do Canal do Panamá, e essa contribuição pode ser valorada em USD 39.640.091 por ano, para toda a floresta da bacia. / Sedimentation and siltation reduce the lakes depth and capacity to hold water in the Panama Canal, requiring periodic dredging which increases the operation costs. These processes are accelerated by the loss of forests that cover the basin. This studys objective is to estimate the economic value associated with reduction of sediments in the Canal basin, based on the method of avoided dredging cost. The physical effect of forest on sediment reduction was estimated through linear regression of biophysical data for seven watersheds that have measurements of sediments yield: Chagres, Pequení, Boquerón, Gatún, Trinidad, Cirí Grande and Caño Quebrado. These results shows that each hectare of forest in this area reduces the sediments in suspension. By adding sediments from the bottom of the riverbed, this corresponds to 14.32 m3.ha- 1.year-1 and to an economic value of USD 197.40 per hectare per year. It was concluded that forests contribute significantly to mitigate the process of siltation of lakes water storage for the operation of the Panama Canal, and this contribution may be valued at USD 39,640,091 per year for the entire basin forest. Bacia hidrográfica Canal do Panamá Custo de operações Deposição de sedimentos Florestas - Impactos físicos Matas ciliares Sedimentologia Valor (Economia). Avoided Cost. Forest covering Panama Canal Sedimentation Watersheds
14	Análise da atuação do Conselho Tutelar frente à evasão escolar de adolescentes no município de Barretos/SP Piana, Maria Cristina [UNESP] January 2003 (has links) (PDF) Made available in DSpace on 2014-06-11T19:29:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T19:18:03Z : No. of bitstreams: 1 piana_mc_me_fran.pdf: 270379 bytes, checksum: a29604fc27f020461cb0f946f1e601a5 (MD5) / Na presente dissertação de mestrado em Serviço Social, apresentamos conhecimentos necessários do órgão municipal – Conselho Tutelar para a atuação no sério problema da evasão escolar que são vítimas tantas crianças e adolescentes de nossa sociedade. Buscamos entender o Conselho Tutelar nas suas atribuições, segundo o artigo 136 da Lei Federal 8.069/90 – Estatuto da Criança e do Adolescente e a sua atuação na gestão 1999 – 2002, quando fomos conselheira tutelar. Os sujeitos de nossa pesquisa foram adolescentes evadidos das escolas estaduais do município de Barretos e atendidos pelo Conselho Tutelar. Pudemos constatar como procede o Conselho Tutelar para o retorno de muitos adolescentes à escola. A investigação do problema da evasão escolar foi também realizada através das entrevistas com profissionais que trabalham direta ou indiretamente com esta questão. Pudemos constatar que o adolescente é vítima de um sistema escolar excludente, elitista e obsoleto. Ao adolescente é necessário oferecer oportunidades e criar formas de participação na construção da sua própria história, sendo sujeitos de direitos e deveres na sociedade à qual se insere. / In the present master’s degree dissertation in Social Service, we presented necessary knowledge of the municipal organ – Guardian Council for the performance in the serious problem of the school escape that are slays so children and adolescents of our society. We looked for to understand the Guardian Council in your attributions, according to the article 136 of the Federal law 8069/90 – Statute of the Child and of the Adolescent and your performance in the administration 1999-2002, when we went guardian counselor. The people of our research were adolescents avoided of the state schools of the municipal district of Barretos and assisted by the Guardian Council. We could verify how it proceeds the Guardian Council for the many adolescents’ return to the school. The investigation of the problem of the school escape was also accomplished through the interviews with professionals that work direct or indirectly with this subject. We could verify that the adolescent is you/he/she slays of an excluding, elitist and obsolete school system. To the adolescent it is necessary to offer opportunities and to create participation forms in the construction of your own history, being subject of rights and duties in the society to which interferes. Inclusão social - Cidadania Conselho Tutelar - Barretos (SP) Guardian Council Inclusion Avoided Schools Citizenship
15	Análise da atuação do Conselho Tutelar frente à evasão escolar de adolescentes no município de Barretos/SP. Piana, Maria Cristina. January 2003 (has links) Orientador: Mário José Filho / Resumo: Na presente dissertação de mestrado em Serviço Social, apresentamos conhecimentos necessários do órgão municipal - Conselho Tutelar para a atuação no sério problema da evasão escolar que são vítimas tantas crianças e adolescentes de nossa sociedade. Buscamos entender o Conselho Tutelar nas suas atribuições, segundo o artigo 136 da Lei Federal 8.069/90 - Estatuto da Criança e do Adolescente e a sua atuação na gestão 1999 - 2002, quando fomos conselheira tutelar. Os sujeitos de nossa pesquisa foram adolescentes evadidos das escolas estaduais do município de Barretos e atendidos pelo Conselho Tutelar. Pudemos constatar como procede o Conselho Tutelar para o retorno de muitos adolescentes à escola. A investigação do problema da evasão escolar foi também realizada através das entrevistas com profissionais que trabalham direta ou indiretamente com esta questão. Pudemos constatar que o adolescente é vítima de um sistema escolar excludente, elitista e obsoleto. Ao adolescente é necessário oferecer oportunidades e criar formas de participação na construção da sua própria história, sendo sujeitos de direitos e deveres na sociedade à qual se insere. / Abstract: In the present master's degree dissertation in Social Service, we presented necessary knowledge of the municipal organ - Guardian Council for the performance in the serious problem of the school escape that are slays so children and adolescents of our society. We looked for to understand the Guardian Council in your attributions, according to the article 136 of the Federal law 8069/90 - Statute of the Child and of the Adolescent and your performance in the administration 1999-2002, when we went guardian counselor. The people of our research were adolescents avoided of the state schools of the municipal district of Barretos and assisted by the Guardian Council. We could verify how it proceeds the Guardian Council for the many adolescents' return to the school. The investigation of the problem of the school escape was also accomplished through the interviews with professionals that work direct or indirectly with this subject. We could verify that the adolescent is you/he/she slays of an excluding, elitist and obsolete school system. To the adolescent it is necessary to offer opportunities and to create participation forms in the construction of your own history, being subject of rights and duties in the society to which interferes. / Mestre Integração social - Cidadania. Guardian Council. eng Inclusion. eng Avoided Schools. eng Citizenship. eng
16	Investigação do processo de foto-ionização associativa em situações com baixa dimensão / Photoassociative ionization in situations with low dimensions Rafael Rothganger de Paiva 17 February 2009 (has links) Neste trabalho estudamos o processo de foto-ionização associativa(PAI) em uma amostra fria de átomos de sódio com o objetivo entender os efeitos dos estados repulsivos e dimensão da colisão. Realizamos experimentos de PAI com duas cores em uma armadilha magneto-óptica adicionando um feixe de prova com intensidade, frequências e polarização ajustáveis. O formato dos átomos aprisionados também foi uma das variáveis no estudo da PAI. Para os átomos em formação esférica, observamos uma mudança marcante no comportamento da constante de taxa de formação da foto-ionização associativa(K) para um determinado domínio de frequências, e essa mudança no comportamento pode ser atribuída a participação de estados moleculares repulsivos na PAI e a formação de um possível cruzamento evitado entre os níveis moleculares. No atomotron ,armadilha atômica em forma de anel, variamos a polarização do laser de prova e constatamos que a razão entre K das polarizações paralela e perpendicular ao movimento dos átomos é igual a 4. Uma comparação entre K do atomotron e o da armadilha esférica em função da intensidade do feixe de prova, nos mostrou uma diferença no comportamento e no valor da constante de taxa. / Photoassociative ionization (PAI) in a cold sample of sodium atoms was the main subject of our studies as a way to understand the effects of repulsive states and collision dimensions. Two-color PAI experiment were preformed in a magneto-optical trap (MOT) trough the addition of a probe laser beam, the intensity, polarization and frequency of that probe laser were tunable. The shape of the trapped atoms also could be changed. In a spherical shape MOT, we observed a marked change in the PAI rate constant (K) for a definite frequency range, and that change can be attributed to the influence of repulsive molecular states and the a possible formation of an avoided crossing between molecular levels. In atomotron, ring shaped mot, we changed the polarization of the probe beam, and saw that the ratio between K for a polarization parallel to the atoms motion and a perpendicular one is 4. Comparing the K as a function of the intensity between a spherical shaped mot and atomotron showed us a difference in the behavior and the value of the rate constant. Armadilha Magneto-óptica Atomotron Colisões atômicas Cruzamento evitado Estado molecular repulsivo Foto-ionização associativa Atomic collisions Atomotron Avoided crossing Magneto-Optical Trap Photo associative ionization Repulsive molecular state
17	Von Übernotation und Unternotation Näf, Lukas, Sackmann, Dominik 01 October 2024 (has links) Das Notierte spielt im klassischen Musikbetrieb eine viel zu große Rolle. Seine ›genaue‹ Befolgung ist die Ursache für allerlei anachronistische Ideologien und Missverständnisse. Die genaue Abstufung der Dynamik anhand der angegebenen Buchstaben steht in markanter Konkurrenz zu den grammatischen, oratorischen und pathetischen Akzenten (H.Chr. Koch) und zur Takthierarchie, wie sie seit dem 15. Jahrhundert gegolten hat. Die Äquidistanz des Notierten führt zur Ideologie des stabilen Tempos, das einem Missverständnis aus einer (falsch verstandenen) Rezipientenperspektive gleichkommt. Die »invitation to collaborate« (Barrett) erstreckt sich einerseits auf die Anreicherung und Variation des Notierten in der solistischen Musik vom 16. bis 20. Jahrhundert, andererseits gelegentlich auch auf eine Reduktion gegenüber dem geschriebenen Melodieverlauf (z. B. in gewissen Klaviersonaten der Wiener Klassik). Diese Denkweise ist noch immer nicht im praktischen Musikbetrieb (inkl. Wettbewerb und Probespiel) angekommen. Unser Beitrag widmet sich angesichts dieser Sachlage der Frage: Wann, wie und mit welcher Absicht notierten Komponisten des 17.–20. Jahrhunderts (von Sweelinck bis Willy Burkhard) Angaben zu Dynamik, Artikulation und Tempomodifikation, und wann und mit welcher Absicht notierten sie diese gerade nicht, um nichts Ungewolltes zu provozieren. Außerdem gehen wir der Frage nach, wo das Fehlen von Aufführungsangaben auch das gewollte Unterbleiben von jeglichen Veränderungen in Tempo, Dynamik und Artikulation bedeutet – als rhetorische Qualität. / What is notated plays far too large a role in the classical music industry. Its ‘exact’ observance is the cause of all kinds of anachronistic ideologies and misunderstandings. The exact gradation of dynamics based on notated letters is in striking competition with grammatical, oratorical and pathetic accents (H.Chr. Koch) and with the metrical hierarchy that has been valid since the 15th century. The equidistance of the notated leads to an ideology of stable tempo, which is tantamount to a misunderstanding from a (misunderstood) recipient’s perspective. The “invitation to collaborate” (Barrett) extends on the one hand to enrichment and variation of what is notated in soloistic music from the 16th to the 20th century, and on the other hand occasionally to a reduction in relation to the written melodic line (e. g. in certain piano sonatas of the Viennese classical period). This way of thinking has still not arrived in general music practice (including competitions and auditions). In view of this situation, our contribution is devoted to this question: when, how and with what intention did composers of the 17th–20th centuries (from Sweelinck to Willy Burkhard) notate indications of dynamics, articulation and tempo modification, and when and with what intention did they not notate them, so as not to provoke anything unwanted. We also explore the question of where the absence of performance indications also means the deliberate omission of any changes in tempo, dynamics and articulation – in the sense of a rhetorical quality. info:eu-repo/classification/ddc/780 ddc:780
18	Use of mode coupling to enhance sound attenuation in acoustic ducts : effects of exceptional point / Utilisation de couplage de modes pour l'amplification de l'atténuation du son dans les conduits acoustiques : effets du point exceptionnel Xiong, Lei 24 March 2016 (has links) Deux stratégies sont présentées à utiliser des effets de couplage de modes pour l’amplification de l’atténuation du son dans les conduits acoustiques. La première est de coupler le mode incident propagatif avec un mode localisé, aussi appelé résonance de Fano. Cette stratégie est présentée et validée dans un système conduit-cavité et un guide d’onde partiellement traité en paroi avec un matériau à réaction locale. La méthode “R-matrix” est introduite pour résoudre le problème de propagation d’onde. Une annulation de la transmission se produit quand un mode piégé (qui est formé par les interférences de deux modes voisins) est excité dans le système ouvert. Ce phénomène est aussi lié au croisement évité des valeurs propres et à un point exceptionnel. Dans la seconde stratégie, un réseau d’inclusions rigides périodiques est intégré dans une couche poreuse pour améliorer l’atténuation du son à basse fréquence. Le couplage de modes est du à la présence de ces inclusions. Le théorème de Floquet-Bloch est proposé pour analyser l’atténuation du son dans un guide d’onde périodique en 2D. Un croisement de l’atténuation de deux ondes de Bloch est observé. Ce phénomène est utilisé pour expliquer le pic de pertes en transmission observé expérimentalement et numériquement dans un guide 3D partiellement traitée par un matériau poreux avec des inclusions périodiques. Enfin, le comportement acoustique d’un liner purement réactif dans un conduit rectangulaire avec et sans écoulement est étudié. Dans une certaine gamme de fréquence, aucune onde ne peut se propager à contre sens de l’écoulement. Par analyse des différent modes à l’aide de la relation de dispersion, il est démontré que le son peut être ralenti et même arrêté. / Two strategies are presented to use the mode coupling effects to enhance sound attenuation in acoustic ducts. The strategy is to couple the incoming propagative mode with the localized mode, which is also called Fano resonance. This strategy is presented and validated in a duct-cavity system and a waveguide partially lined with a locally reacting material. The R-matrix method is introduced to solve the propagation problems. A zero in the transmission is present, due to the excitation of a trapped mode which is formed by the interferences of two neighboured modes. It is also linked to the avoided crossing of the eigenvalues and exceptional point. In the second strategy, a set of periodic rigid inclusions are embedded in a porous lining to enhance sound attenuation at low frequencies. The mode coupling is due to the presence of the embedded inclusions. Floquet - Bloch theorem is proposed to investigate the attenuation in a 2D periodic waveguide. Crossing is observed between the mode attenuations of two Bloch waves. The most important and interesting figure is that near the frequency where the crossing appears, an attenuation peak is observed. This phenomenon can be used to explain the transmission loss peak observed numerically and experimentally in a 3D waveguide partially lined by a porous material embedded with periodic inclusions. Finally, the acoustical behaviours of a purely reacting liner in a duct in absence and presence of flow are investigated. The results exhibit an unusual acoustical behaviour : for a certain range of frequencies, no wave can propagate against the flow. a negative group velocity is found, and it is demonstrated that the sound can be slowed down and even stopped. Méthode R-matrix Mode piégé Résonance de Fano Croisement évité Point exceptionnel Atténuation du son Ondes de Bloch R-matrix method Trapepd mode Fano resonance Avoided crossing Exceptional point Sound attenuation Bloch wave 534.208
19	Hydrogen Pipeline Infrastructure Design for Germany in 2045 von Mikulicz-Radecki, Flora Marianne January 2023 (has links) Germany’s commitment to carbon neutrality by 2045 underscores the need for climate action, with hydrogen’s multiple uses in industry, transport, and energy offering a viable solution. Efficient retrofitting of the extensive natural gas pipeline network can enable hydrogen to be transported from supply to demand centers. The aim of this study is to develop a hydrogen pipeline network strategy for Germany in 2045 that is consistent with carbon neutrality goals while minimizing associated costs. Using a single-period deterministic Mixed Integer Linear Programming (MILP) approach, the focus is on estimating peak-hour transport demand derived from the spatial distribution of demand and supply. This estimation is based on openly available data from the Germany Energy Agency (dena) pilot study on carbon neutrality. The methodology aims to allocate hydrogen energy flows along existing pipelines through a retrofitting approach. The base scenario is derived from the projected hydrogen demand and supply for a carbon-neutral Germany in 2045, as estimated in the dena pilot study. To explore different possibilities, a sensitivity analysis compares five different demand scenarios. Each scenario examines different hard-to-abate subsectors that have limited options for decarbonization. Evaluating the routes and utilization rates across the pipeline network provides insights into the feasibility, with certain routes, particularly those originating in the north, emerging as key. The majority of pipelines in the network have low utilization rates below 25% in peak hours, which may indicate economic infeasibility or the need for alternative transport strategies. In addition, a cost of avoided emissions analysis weighs scenario-specific emission reductions against network costs. Of particular note is the network connecting CHP plants and energy-intensive industries, which appears to strike an optimal balance in terms of costs of avoided emissions and utilization rate in peak hours. Nevertheless, the study does not consider physical flow calculations, so further validation is required in this respect. The potential of the methodology, however, liesin its ability to quickly assess different scenarios and provide valuable insights into economic, environmental, and social impacts. / Tysklands åtagande om koldioxidneutralitet senast 2045 understryker behovet av klimatåtgärder, och vätgasens många användningsområden inom industri, transport och energi erbjuder en hållbar lösning. Effektiv eftermontering av det omfattande naturgasledningsnätet kan göra det möjligt att transportera vätgas från utbuds- till efterfrågecentra. Syftet med denna studie är att utveckla en strategi för vätgasnätet i Tyskland 2045 som är förenlig med målen för koldioxidneutralitet och samtidigt minimerar de tillhörande kostnaderna. Med hjälp av en deterministisk MILP-metod (Mixed Integer Linear Programming) för en enda period ligger fokus på att uppskatta efterfrågan på transporter under maxtimmar utifrån den rumsliga fördelningen av efterfrågan och utbud. Denna uppskattning baseras på öppet tillgängliga data från denas pilotstudie om koldioxidneutralitet. Metoden syftar till att fördela vätgasenergiflöden längs befintliga rörledningar genom en eftermonteringsstrategi. Det grundläggande scenariot härleds från den beräknade efterfrågan och tillgången på vätgas för ett koldioxidneutralt Tyskland 2045, enligt uppskattningar i dena-pilotstudien. För att utforska olika möjligheter jämförs fem olika efterfrågescenarier i en känslighetsanalys. Varje scenario undersöker olika delsektorer som är svåra att minska och som har begränsade alternativ för utfasning av fossila bränslen. Utvärderingen av sträckningarna och utnyttjandegraden i rörledningsnätet ger insikter om genomförbarheten, där vissa sträckningar, särskilt de med ursprung i norr, framstår som viktiga. Majoriteten av rörledningarna i nätverkethar låga nyttjandegrader under 25% under rusningstid, vilket kan indikera ekonomisk ogenomförbarhet eller behovet av alternativa transportstrategier. Dessutom väger en kostnads-/nyttoanalys av utsläpp scenariospecifika utsläppsminskningar mot nätverkskostnader. Särskilt värt att notera är det nätverk som förbinder kraftvärmeverk och energiintensiva industrier, vilket verkar ge en optimal balans när det gäller kostnader för utsläpp och nyttjandegrad. Studien tar dock inte hänsyn till fysiska flödesberäkningar, så ytterligare validering krävs i detta avseende. Metodens potential ligger dock i dess förmåga att snabbt bedöma olika scenarier och ge värdefulla insikter om ekonomiska, miljömässiga och sociala effekter. Hydrogen Transport Infrastructure Pipeline Networks Retrofitting Infrastructure Planning Peak Hour Hydrogen Demand Utilization Rate Costs of Avoided Emissions Carbon Neutrality Infrastruktur för vätgastransport rörledningsnät eftermontering infrastrukturplanering efterfrågan på vätgas under m Engineering and Technology Teknik och teknologier
20	Analysis of a novel thermoelectric generator in the built environment Lozano, Adolfo 05 October 2011 (has links) This study centered on a novel thermoelectric generator (TEG) integrated into the built environment. Designed by Watts Thermoelectric LLC, the TEG is essentially a novel assembly of thermoelectric modules whose required temperature differential is supplied by hot and cold streams of water flowing through the TEG. Per its recommended operating conditions, the TEG nominally generates 83 Watts of electrical power. In its default configuration in the built environment, solar-thermal energy serves as the TEG’s hot stream source and geothermal energy serves as its cold stream source. Two systems-level, thermodynamic analyses were performed, which were based on the TEG’s upcoming characterization testing, scheduled to occur later in 2011 in Detroit, Michigan. The first analysis considered the TEG coupled with a solar collector system. A numerical model of the coupled system was constructed in order to estimate the system’s annual energetic performance. It was determined numerically that over the course of a sample year, the solar collector system could deliver 39.73 megawatt-hours (MWh) of thermal energy to the TEG. The TEG converted that thermal energy into a net of 266.5 kilowatt-hours of electricity in that year. The second analysis focused on the TEG itself during operation with the purpose of providing a preliminary thermodynamic characterization of the TEG. Using experimental data, this analysis found the TEG’s operating efficiency to be 1.72%. Next, the annual emissions that would be avoided by implementing the zero-emission TEG were considered. The emission factor of Michigan’s electric grid, RFCM, was calculated to be 0.830 tons of carbon dioxide-equivalent (CO2e) per MWh, and with the TEG’s annual energy output, it was concluded that 0.221 tons CO2e would be avoided each year with the TEG. It is important to note that the TEG can be linearly scaled up by including additional modules. Thus, these benefits can be multiplied through the incorporation of more TEG units. Finally, the levelized cost of electricity (LCOE) of the TEG integrated into the built environment with the solar-thermal hot source and passive ground-based cold source was considered. The LCOE of the system was estimated to be approximately $8,404/MWh, which is substantially greater than current generation technologies. Note that this calculation was based on one particular configuration with a particular and narrow set of assumptions, and is not intended to be a general conclusion about TEG systems overall. It was concluded that while solar-thermal energy systems can sustain the TEG, they are capital-intensive and therefore not economically suitable for the TEG given the assumptions of this analysis. In the end, because of the large costs associated with the solar-thermal system, waste heat recovery is proposed as a potentially more cost-effective provider of the TEG’s hot stream source. / text Thermoelectric generator TEG Novel thermoelectric generator Thermoelectrics Thermoelectric effect Thermoelectric modules Thermoelectric device Patent application Hot stream source Cold stream source EIA EERE Systems-level analysis Energy balance Control volume analysis Thermodynamic analysis Insolation data Insolation incident on a panel Incident insolation Extraterrestrial insolation NREL Ambient temperature data NOAA Renewable energy sources Energy generation technology Electricity generation technology Thermal energy Coupled system Emissions Greenhouse gas GHG Emissions analysis Zero-emission Emissions avoided Emission factor EF Reliability First Corporation RFC Built environment Integrated into the built environment Solar-thermal energy Solar collector system Photovoltaic thermal PVT panel Thermal storage tank Geothermal energy Geothermal heat pump GHP Ground source heat pump GSHP Numerical analysis Numerical model MATLAB Finite-difference Euler explicit Electric grid Annual energetic performance Annual electricity generation Operating efficiency System efficiency Thermodynamic characterization Economic analysis Levelized cost of energy LCOE Waste heat recovery Carbon dioxide equivalent CO2e Capital costs Installed costs Operating and maintenance costs

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