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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

由企業角度研究碳足跡標籤的導入:以宏碁與泰山為例 / Implementing carbon footprint labelling scheme from a business perspective: company Acer and Taisun, Taiwan-based companies as examples

吳思頤, Wu, Szu-I (Sandy) Unknown Date (has links)
隨著消費者開始意識到自身的購買行為對於環境的影響,環境友善的產品也越來越受歡迎.碳足跡標籤,也就是在標籤上註明一件產品的生命週期所產生的所有碳排放,而其過程就包括了從原料取得到最後被丟棄的整個產品生命週期.產品碳足跡標籤讓消費者了解產品的環境友善程度,也幫助消費者做對環境友善的購買決策.碳足跡標籤也讓消費者成為帶動更永續的未來的主要推力,並激勵企業製造碳足跡較低的產品來維持競爭力. 碳足跡標籤已在全球成為一個越來越普遍的行為,而台灣也正開始推動碳足跡標籤方案.此論文深入研究已發展國家包括英國,美國,法國,日本以及跨國公司包括Walkers,Walmart和Casion Group如何導入碳足跡標籤方案. 接下來將探討台灣以及台灣企業是如何將碳足跡標籤導入到公司以及過程中所碰到的問題與機會. 在台灣企業的部分,宏碁以及泰山為研究對象,由於這兩家企業都是在碳足跡標籤方案的先驅者,並且為不同的產業背景,因此挑選了這兩家深入研究,並探討不同產業導入碳標籤方案的作法. / As consumers become conscious of the impacts of their purchase decision on the environment, environmental friendly products become increasingly popular. By indicating the amount of carbon dioxide produced and emitted throughout a product’s life cycle, from material acquisition to manufacturing to consumption, carbon footprint label give consumers the information to make earth-friendly purchase decisions. Carbon footprint label also makes consumers the driver of a more sustainable future by incentivizing businesses to make lower GHG-content products to increase the competitiveness of products. Carbon footprint label is becoming a popular practice around the world. Taiwan is also learning and doing carbon footprint labelling. This dissertation investigates how carbon footprint labelling is done in advanced countries including the United Kingdom, the United States, France, and Japan and multinational companies including Walkers, Walmart and Casino Group. Then it investigates how carbon footprint labelling is done in Taiwan and how Taiwan businesses approach carbon footprint labelling. Two companies of different industry were interviewed to gain an in-depth understanding of how and why Taiwan businesses implement carbon footprint labelling. From the interviews, insights of the motivation, project planning, execution and questions encountered during the implementation of carbon footprint labelling were revealed. The dissertation then concludes by discussing the limitations that happened during the research and the suggestions for the development of Taiwan’s carbon footprint label.
472

Petit périple aux confins du modèle standard avec HERA

Sauvan, E. 30 October 2009 (has links) (PDF)
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473

Première mesure des sections efficaces de courant chargé et neutre avec le faisceau de positrons polarisé à HERA II et analyses QCD-électrofaibles

Portheault, B. 29 March 2005 (has links) (PDF)
En 2003-2004 le collisionneur HERA à délivré des collisions $e^+p$ avec un faisceau de positrons polarisé longitudinalement. Ce travail présente la mesure des section efficaces de DIS inclusive polarisées Courant Neutre et Courant Chargé avec le détecteur H1 en utilisant un lot de données de 15,3 pb$^(-1)$ de polarisation moyenne $P=0,33$ et un lot de données de 21,7 pb$^(-1)$ de polarisation moyenne $P=-0,40$. La mesure de la section efficace CC totale pour $Q^2>400$ GeV$^2$, $y<0,9$ donne \begin(eqnarray \sigma_(CC)(P=+0,33)&=& 34,67\mbox( pb )\pm 1,94\mbox( pb )\:(\mbox(stat))\pm 1,66\mbox( pb )\:(\mbox(sys)) \\ \sigma_(CC)(P=-0,40)&=& 13,80\mbox( pb )\pm 1,04\mbox( pb )\:(\mbox(stat))\pm 0,94\mbox( pb )\:(\mbox(sys)). \end(eqnarray) En accord avec le Modèle Standard qui prédit la proportionnalité de la section efficace avec la polarisation. Dans une deuxième partie, on réalise une analyse QCD des données de H1 pour extraire les densités de partons. Cette analyse est ensuite étendue à la détermination jointe des paramètres électrofaibles comme la masse du boson $W$ et des couplages des quarks au boson $Z$. Une analyse QCD globale des données de DIS et de Drell-Yan est réalisée, en particulier utilisée pour obtenir l'asymétrie de la mer étrange $\int_0^1 x(s-\bar(s))\mathrm(d)x=(1,8\pm3,8)\times10^(-4)$. L'impact des nouvelles données de E866 sur les densités de quark à très grand $x$ est discuté. On obtient une extraction de la constante de couplage forte $\alpha_s=0,1197\pm0,0008 \mbox( (exp)) ()^(+0,0005)_(-0,0007)\mbox( (mod))\pm0,006 \mbox( (th))$.
474

Polymères neutres solubles dans l'eau : Origine et signatures de la dépendance en concentration du paramètre de Flory chi

Baulin, Vladimir 06 October 2003 (has links) (PDF)
Ce travail est consacré à l'étude d'origine et signatures de la dépendance en concentration $\phi$ du paramètre de Flory $\chi _(eff)$ pour les polymères neutres solubles dans l'eau. Les trois versions du modèle à deux états qui ont été proposés pour expliquer le comportement de phase de Poly(oxyéthylène) dans l'eau mènent à $\chi _(eff)(\phi) $. Cette dépendance peut servir à tester la qualité des modèles: elle permet de distinguer entre les différents modèles et juger de la pertinence des paramètres impliqués. L'apparition de $\chi _(eff)(\phi)$ à partir des modèles alternatifs à un seul état est aussi discutée. Les signatures macroscopiques de $\chi _(eff)(\phi)$ sont illustrées avec l'exemple du gonflement des chaînes isolées et des brosses planes. La dépendance de $\chi _(eff)$ avec $\phi$ dans les systèmes à concentration uniforme a deux conséquences principales: entraînement du déplacement du croisement entre les régimes Gaussien et auto-évitant, et la possibilité d'une transition de phase du premier ordre pour les chaînes flexibles isolées. $\chi _(eff)(\phi)$ peut provoquer une séparation verticale de phase dans des brosses polymères qui implique la coexistence de deux phases de concentration finie. Cette approche est appliquée à l'interprétation d'un ensemble des résultats expérimentaux qui suggère que cet effet pourrait exister avec les brosses de Poly(N-isopropylacrylamide).
475

Instrumentation for energetic Neutral atom measurements at Mars, Venus and The Earth

Brinkfeldt, Klas January 2005 (has links)
<p>This thesis deals with the development and calibrations of sensors to measure energetic neutral atoms (ENAs) at Mars, Venus, and the Earth. ENAs are formed in charge exchange processes between energetic, singly--charged ions and a cold neutral gas. Since ENAs can travel in long straight trajectories, unaffected by electric or magnetic fields, they can be used to remotely image plasma interactions with neutral atmospheres. ENA instrument techniques have matured over the last decade and ENA images of the Earth's ring current for example, have successfully been analyzed to extract ion distributions and characterize plasma flows and currents in the inner magnetosphere.</p><p>Three different ENA sensors have been developed to image ENAs at Mars, Venus, and the Earth. Two of them, the nearly identical Neutral Particle imagers (NPIs) are on-board the Mars Express and Venus Express spacecraft as a part of the Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3 and 4) instruments. The third is the Neutral Atom Detector Unit, NUADU, aboard the TC-2 spacecraft of the Double Star mission. The NPI design is based on a surface reflection technique to measure low energy (~0.3-60 keV) ENAs, while the NUADU instrument is based on a simple design with large geometrical factor and solid state detectors to measure high energy ENAs (~20-300 keV).</p><p>The calibration approach of both NPI sensors were to define the detailed response, including properties such as the angular response function and efficiency of one reference sensor direction then find the relative response of the other sensor directions. Because of the simple geometry of the NUADU instrument, the calibration strategy involved simulations to find the cutoff energy, geometrical factor and angular response. The NUADU sensor head was then calibrated to find the response to particles of different mass and energy. The NPI sensor for the Mars Express mission revealed a so-called priority effect in the sensor that lowers the angular resolution at high detector bias. During the calibration of the Venus Express NPI sensor tests were made which showed that the priority effect is a result of low amplitude (noise) pulses generated in the detector system. The conclusion is that the effect is caused by capacitive couplings between different anode sectors of the sensor. The thresholds on the preamplifiers were set higher on the Venus Express NPI, which removed the priority effect.</p><p>Two of the three ENA experiments, the Double Star NUADU instrument and the Mars Express NPI sensor, have successfully measured ENAs that are briefly described in the thesis. The first ENA measurements at Mars were performed with Mars Express. Initial results from the NPI include measurements of ENAs formed in the Martian magnetosheath and solar wind ENAs penetrating to the nightside of Mars. The first results from NUADU in Earth orbit show the expected ENA emissions from a storm time ring current. Also, together with the HENA instrument on the IMAGE spacecraft, NUADU have produced the first multi-point ENA image of the ring current.</p>
476

Stochastic Volatility Models for Contingent Claim Pricing and Hedging.

Manzini, Muzi Charles. January 2008 (has links)
<p>The present mini-thesis seeks to explore and investigate the mathematical theory and concepts that underpins the valuation of derivative securities, particularly European plainvanilla options. The main argument that we emphasise is that novel models of option pricing, as is suggested by Hull and White (1987) [1] and others, must account for the discrepancy observed on the implied volatility &ldquo / smile&rdquo / curve. To achieve this we also propose that market volatility be modeled as random or stochastic as opposed to certain standard option pricing models such as Black-Scholes, in which volatility is assumed to be constant.</p>
477

Instrumentation for energetic Neutral atom measurements at Mars, Venus and The Earth

Brinkfeldt, Klas January 2005 (has links)
This thesis deals with the development and calibrations of sensors to measure energetic neutral atoms (ENAs) at Mars, Venus, and the Earth. ENAs are formed in charge exchange processes between energetic, singly--charged ions and a cold neutral gas. Since ENAs can travel in long straight trajectories, unaffected by electric or magnetic fields, they can be used to remotely image plasma interactions with neutral atmospheres. ENA instrument techniques have matured over the last decade and ENA images of the Earth's ring current for example, have successfully been analyzed to extract ion distributions and characterize plasma flows and currents in the inner magnetosphere. Three different ENA sensors have been developed to image ENAs at Mars, Venus, and the Earth. Two of them, the nearly identical Neutral Particle imagers (NPIs) are on-board the Mars Express and Venus Express spacecraft as a part of the Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3 and 4) instruments. The third is the Neutral Atom Detector Unit, NUADU, aboard the TC-2 spacecraft of the Double Star mission. The NPI design is based on a surface reflection technique to measure low energy (~0.3-60 keV) ENAs, while the NUADU instrument is based on a simple design with large geometrical factor and solid state detectors to measure high energy ENAs (~20-300 keV). The calibration approach of both NPI sensors were to define the detailed response, including properties such as the angular response function and efficiency of one reference sensor direction then find the relative response of the other sensor directions. Because of the simple geometry of the NUADU instrument, the calibration strategy involved simulations to find the cutoff energy, geometrical factor and angular response. The NUADU sensor head was then calibrated to find the response to particles of different mass and energy. The NPI sensor for the Mars Express mission revealed a so-called priority effect in the sensor that lowers the angular resolution at high detector bias. During the calibration of the Venus Express NPI sensor tests were made which showed that the priority effect is a result of low amplitude (noise) pulses generated in the detector system. The conclusion is that the effect is caused by capacitive couplings between different anode sectors of the sensor. The thresholds on the preamplifiers were set higher on the Venus Express NPI, which removed the priority effect. Two of the three ENA experiments, the Double Star NUADU instrument and the Mars Express NPI sensor, have successfully measured ENAs that are briefly described in the thesis. The first ENA measurements at Mars were performed with Mars Express. Initial results from the NPI include measurements of ENAs formed in the Martian magnetosheath and solar wind ENAs penetrating to the nightside of Mars. The first results from NUADU in Earth orbit show the expected ENA emissions from a storm time ring current. Also, together with the HENA instrument on the IMAGE spacecraft, NUADU have produced the first multi-point ENA image of the ring current.
478

The Behaviour of the Latent Heat Exchange Coefficient in the Stable Marine Boundary Layer

Lindgren, Kristina January 2008 (has links)
Knowledge of the turbulent fluxes at the sea surface is important for understanding the interaction between atmosphere and ocean. With better knowledge, improvements in the estimation of the heat exchange coefficients can be made and hence models are able to predict the weather and future climate with higher accuracy. The exchange coefficients of latent and sensible heat during stable stratification vary in the literature. Therefore it is necessary to investigate the processes influencing the air-sea exchange of water vapour and heat in order to estimate these values. With measurements from a tower and a directional waverider buoy at the site Östergarnsholm in the Baltic Sea, data used in this study have been sampled from the years 2005-2007. This site represents open-ocean conditions during most situations when the wind comes from the south-east sector. The neutral exchange coefficients, CEN and CHN, have been calculated along with the non-dimensional profile functions for temperature and wind to study the dependence of stability and other parameters of relevance. It was found that CEN increased slightly with wind speed and reached a mean value of approximately 1.45×10-3. The highest values of CEN were observed during near neutral conditions and low wave ages. CHN attained a mean value of approximately 0.77×10-3 and did not show any relation to wind speed or to wave age. No significant dependence with wind or wave direction could be shown for either CEN or CHN in the sector 80-220°. The stability correction, performed to reduce the dependence on stratification for CEN and CHN, was well performed for stabilities higher than 0.15. The stability is represented by a relationship between the height and the Obukhov-length (z/L). Validity of the non-dimensional profile functions for temperature and wind showed that, for smaller stabilities, these functions gave higher values than the corresponding functions recommended by Högström (1996). The profile funtions for temperature was shown to have a larger scatter while the profile functions for wind was less scattered and deviated more from the functions given by Högström / Kunskap om turbulenta flöden i det marina gränsskiktet är viktigt för att förstå växelverkan mellan atmosfär och hav. Med bättre kunskap kan förbättringar i bestämningen av utbyteskoefficienterna för latent och sensibelt värme erhållas. Det medför att modeller kan prognostisera väder och framtida klimat med högre noggrannhet. Utbyteskoefficienterna för latent och sensibelt värme har för stabil skiktning olika värden i litteraturen. Detta gör det nödvändigt att undersöka de processer som påverkar utbytet av vattenånga och värme mellan luft och hav för att kunna bestämma dessa värden. Data som har använts i den här studien insamlades mellan år 2005 och 2007 från en boj och ett torn vid mätplatsen Östergarnsholm i Baltiska havet. För det flesta situationer, när vinden blåser från syd-ost, representerar mätplatsen ett förhållande likvärdigt det över öppet hav. De neutrala utbyteskoefficienterna, CEN och CHN, och de dimensionslösa profilfunktionera för temperatur och vind, och , har beräknats för att studera beroendet av stabilitet samt andra relevanta parametrar. Beräkningarna visade att CEN ökade något med vindhastighet och hamnade på ett medelvärde av ungefär 1.45×10-3. De högsta värdena på CEN observerades vid nära neutrala förhållanden och låga vågåldrar. CHN uppmättes till att ha ett medelvärde på ungefär 0.77×10-3 och uppvisade inget beroende med vindhastighet eller vågålder. Inget märkbart beroende med vind- eller vågriktning kunde visas för CEN eller CHN i sektorn 80-220°. Stabilitetskorrektionen, utförd för att reducera beroendet av atmosfärens skiktning för CEN och CHN, var bra för stabiliteter högre än 0.15. Stabiliteten representeras av förhållandet mellan höjden och Obukhov-längden (z/L). Utvärdering av de dimensionslösa funktionerna för temperatur och vind visade att dessa funktioner, för små stabiliteter, gav högre värden än motsvarande funktioner som rekommenderas av Högström (1996). Värdena på profilfunktionerna för temperatur hade större spridning än värdena på profilfunktionerna för vind och avvek mer från funktionerna givna av Högström.
479

Kivi är en han, inte en hen : Om förskolebarns tillskrivande av kön i samtal om en könlös bok / Kivi is a he, not a hen : About pre-school children's ascribing of gender in conversation about a genderless book

Lindström, Sandra January 2013 (has links)
I den stora hen-debatten under 2012 saknades barnens perspektiv. Syftet med denna uppsats är att belysa det genom att ta reda på vilka pronomen förskolebarn använder i sitt samtalande om barnboken Kivi och monsterhund som endast innehåller könsneutrala pronomen. Materialinsamlingen gjordes genom barnintervjuer i fokusgrupper där fyra- och femåriga förskolebarn fick samtala om boken och som analyseringsmetod har en mestadels kvantitativ metod använts för att ta reda på pronomenens frekvens. Resultaten visar att barnen inte reagerade nämnvärt på hen och använde det inte heller själva. Kivi omnämndes av barnen som han medan monsterhunden refererades till som den eller han.  Hypotesen att barnen skulle tillskriva Kivi sitt eget kön visade sig inte stämma då skillnaderna i pronomenanvändning pojkar och flickor emellan var minimala. Resultaten kan bero på att mannen ses som norm och kvinnor som ”det Andra” (de Beauvoir 2002) samt att barnlitteraturen domineras av pojkar. Resultaten överensstämmer också med tidigare forskning av Merrit &amp; Kok (1995) som visar att karaktärer med könsneutrala namn tenderar att tillskrivas manligt kön. / In the great debate over the gender-neutral pronoun hen in 2012, the perspective of the children was missing. The aim of this bachelor essay is to shed light on that perspective by investigating which pronouns pre-school children use in conversation about the children’s book Kivi och monsterhund which contains only gender-neutral pronouns. The material was obtained through children’s interviews in focus groups where four- and five-year-old pre-school children talked about the book and the material was analyzed by using a mostly quantitative method to find out the frequency of the used pronouns. The results show that the children scarcely reacted to hen nor did they use it themselves. Kivi was referred to by the children as he while monsterhunden (the monster dog) was referred to as it or he. The hypothesis that the children would ascribe Kivi their own gender proved to be incorrect as the differences in use of pronouns between boys and girls were minimal. The results may be an effect of the man being viewed as the norm and women as “the Other” (de Beauvoir 2002) and the dominance of boys in children’s literature. The results also correlate to previous research by Merrit &amp; Kok (1995) that show that characters with gender-neutral names tend to be ascribed male gender.
480

Measurement of High-Q2 Neutral Current Cross-sections with Longitudinally Polarised Positrons with the ZEUS Detector

Stewart, Trevor 07 January 2013 (has links)
The cross sections for neutral current (NC) deep inelastic scattering (DIS) in e+p collisions with a longitudinally polarised positron beam are measured at high momentum transfer squared (Q2 > 185 GeV2) at the ZEUS detector at HERA. The HERA accelerator provides e+-p collisions at a centre-of-mass energy of 318 GeV, which allows the weak contribution to the NC process to be studied at high Q2. The measurements are based on a data sample with an integrated luminosity of 135.5 pb-1 collected with the ZEUS detector in 2006 and 2007. The single differential NC cross sections dsigma/dQ2, dsigma/dx and dsigma/dy and the reduced cross section are measured. The structure function xF3 is determined by combining the e+p NC reduced cross sections with the previously measured e-p measurements. The interference structure function xF 3^gamma,Z is extracted at Q2 = 1500 GeV2. The cross-section asymmetry between the positive and negative polarisation of the positron beam is measured and the parity violation effects of the electroweak interaction are observed. The predictions of the Standard Model of particle physics agree well with the measurements.

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