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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.
61

Small Scale Sustainability : A Qualitative Study of Corporate Sustainability in Swedish SMEs

Alvesson Due Billing, Miha January 2016 (has links)
This qualitative study aims to contribute to the research field on corporate sustainability (CS) in small and medium-sized enterprise (SMEs), in hopes of helping policymakers better understand the circumstances for Swedish SMEs and how they work with CS. Empirical data about motivations behind working with CS, implementation of CS activities, and effects of CS work were collected through in-depth interviews with 18 company representatives. The major reason for motivation was found to be personal interest and commitment to these kind of practices, followed by strengthening the competitiveness, marketing, initiative from management and board, and profitability aspects. The implementation process is often informal in nature with concrete measures and activities rather than formal policies and strategies, although a few of the companies make use of tools such as environmental management systems. How the companies communicate their CS work differs and the response from stakeholders varies too. Lastly, profitability was found to be an important effect for some, while others more heavily emphasize the personal satisfaction from doing the right thing and being sustainable. The social effects were mostly improved working conditions and more engagement from stakeholders, while the environmental impact was understood to mostly concern a decrease in consumption of finite resources, and a more efficient use of material and energy. Suggestions for improving CS work in Swedish SMEs are increased support and encouragement from the government, and more education and information about what companies can do and how they can do it with appropriate tools. Concluding, CS in Swedish SMEs must be studied further to gain a more comprehensive picture of how to support those SMEs already working with CS and those in the path of transitioning towards a more sustainable development.
62

Recipientundersökning av Ensjön : Bedömning av sulfidmalmgruvan Enåsens eventuella påverkan på sjöns vattenkvalitet

Enmark, Gustav January 2007 (has links)
<p>Ensåsengruvan is a mine situated within Ljusdals municipality in central Sweden. Themine was in use from 1984 to 1991 and has since been undergoing a remediation program. Mine tailings from sulfide rich ore is a potential environmental hazard due to its tendency to cause acid waters and heavy metal leakage. Lake Ensjön is situated one kilometer from the mine area. Due to the hydrological conditions it was not expected to receive inflowing water from the mining area. A study done in 2005 showed high amounts of heavy metals in the lake.</p><p>In this study water and sediments was analyzed to confirm the results from the 2005 study. Water was sampled two times during summer 2006 from the lake and adjoining streams. Sediment samples were collected with a core sampler at ten different locations within the lake. The water and sediment samples were analyzed for heavy metal content. Sub-samples from different depths in the sediment core were extracted so that conclusions on the contamination history could be drawn. The sediments were dated trough Cs-137 analyses. The depth in the profile with the highest Cs-137 content can be dated to the time of the Chernobyl fallout (1986). After dating, relevant samples were analyzed for metal content.</p><p>The results show that Ensjön is contaminated by a local source. The surface sediments are high in copper, zinc, nickel and cadmium content. The content is high both compared to the samples from deeper in the sediment core and the surface sediments analyzed in the reference study done in 1980. The amounts of heavy metals are also high relative to the standards set by the Swedish Environmental Protection Agency. The water from the stream adjoining the lake from the mining area is high in content of the previously mentioned metals. The methods used, including sediment dating and metal analyses together with water analyses, has proven to be useful in investigating a suspected contamination from a point source.</p><p>It can be concluded that Lake Ensjön is contaminated with water from the mine waste. No other sources in the catchment area can be the source of the enriched amounts of heavy metals. Focus should in further work be put upon finding the exact source of leakage from the mining area.</p> / <p>Från Enåsengruvan i Ljusdals kommun utvanns ur sulfidmalm guld, silver och koppar under åren 1984 till 1991. Avfall från sulfidmalmsgruvor medför miljöproblem genom försurning och läckage av tungmetaller. Vanligtvis täcks avfallet med jordmassor eller vatten för att förhindra påverkan på naturen. De studier som genomfördes under prospekteringen visade på att Ensjön, som är belägen inom en kilometers avstånd från gruvområdet, inte skulle påverkas av gruvan men en provtagning under 2005 visade på höga halter av tungmetaller i sjön.</p><p>I denna studie har Ensjöns vattenkvalitet undersökts genom vatten och sedimentanalyser. Vattenprover i sjön och dess inlopp togs två gånger under sommaren 2006 och sedimentprover togs vid ett tillfälle på tio olika lokaler i sjön. En djupprofil av sedimenten analyserades för att föroreningshistoriken från innan gruvan togs i bruk till nutid skulle kunna kartläggas. För att datera sedimenten analyserades de med avseende på Cs-137. De högsta halterna av Cs-137 kan härledas till nedfallet från Tjernobylolyckan 1986. Efter datering valdes lämpliga prover ut för metallanalys.</p><p>Resultaten visar på förhöjda halter av koppar, zink, nickel och kadmium. Halterna i ytsedimenten är höga både jämfört med de halter som återfinns på större djup i sedimentprofilen, motsvarande avsättning innan gruvdriften och vad som uppmättes i referensstudien från 1980. Halterna är även höga relativt de jämförvärden som Naturvårdsverket satt upp. Vattenanalyserna visar på att vattnet i inflödet från gruvområdet innehåller höga halter av de tidigare nämnda metallerna. Metoden med Cs-137-datering och analys med avseende på metaller av sediment har visat sig fungera väl för kartläggning av en nutida förorening från en punktkälla. Tillsammans med kompletterande vattenprover ger det en bra bild av den rådande situationen.</p><p>Då resultaten visar att Ensjöns vatten är påverkat av en punktkälla och alla andra källor kan uteslutas får det anses klarlagt att sjöns vatten är påverkat av dränagevatten från gruvområdet. Fortsatta studier bör fokusera på att klarlägga den exakta källan till läckaget från gruvområdet.</p>
63

From Alphas to Epsilons : A study of eugenics and social caste in Aldous Huxley’s Brave New World from a biographicalperspective

Kringstad, Johan January 2017 (has links)
AbstractThis essay discusses the concepts of eugenics and social caste in Brave New Worldin relation to Aldous Huxley, from a biographical perspective. The essay analyzes how events and personal relationships of Aldous Huxley have influenced the depiction of the concepts social caste and eugenics in his novel Brave New World. Using sources which recount the travels and the personal encounters that Aldous Huxley made throughout his life, this essay makes comparisons and draws conclusions as to how these eventsand relationshipshave affected the depiction of social caste and eugenics in Brave New World
64

Plasma vertical position control in the COMPASS–D tokamak

Vyas, Parag January 1996 (has links)
The plasma vertical position system on the COMPASS–D tokamak is studied in this thesis. An analogue P+D controller is used to regulate the plasma vertical position which is open loop unstable. Measurements from inside the vessel are used for the derivative component of the control signal and external measurements for the proportional component. Two main sources of disturbances are observed on COMPASS–D. One source is 600Hz noise from thyristor power supplies which cause large oscillations at the control amplifier output. Another source is impulse–like disturbances due to ELMs (Edge Localized Modes) and this can occasionally lead to loss of control when the control amplifier saturates. Models of the plasma open loop dynamics were obtained using the process of system identification. Experimental data is used to fit the coefficients of a mathematical model. The frequency response of the model is strongly dependent on the shape of the plasma. The effect of shielding by the vessel wall on external measurements when compared with internal measurements is also observed. The models were used to predict values of gain margins and phase crossover frequencies which were found to be in good agreement with measured values. The harsh reactor conditions on the proposed ITER tokamak preclude the use of internal measurements. On COMPASS–D the stability margins of the loop decrease when using only external flux loops. High order controllers were designed to stabilize the system using only external measurements and to reduce the effect of 600Hz noise on the control amplifier voltage. The controllers were tested on COMPASS–D and demonstrated the improved performance of high order controllers over the simple P+D controller. ELMs cause impulse–like disturbances on the plasma position. The optimal controller minimizing the peak of the impulse response can be calculated analytically for COMPASS–D. A multiobjective controller which combines a small peak impulse response with robust stability and noise attenuation can be obtained using a numerical search.
65

Partitioning of Sr-90 and Cs-137 in nuclear fuel storage ponds

Ashworth, Hollie January 2017 (has links)
Sr-90 and Cs-137 are two key fission products that are important in a number of radioactive waste or contamination clean-up scenarios. This thesis investigates the sorptiondesorption behaviour of these two radionuclides with a number of sorbents relevant to one of the legacy waste storage ponds on the Sellafield site. Sorption-desorption studies were undertaken on brucite (Mg(OH)2), UO2 and UO3 powders to represent components of the fine particulate sludge that has accumulated on the bottom of the pond, resulting from corrosion of the Magnox fuel elements. Brucite was found not to have a significant interaction with Sr-90 or Cs-137. However, organic molecules in the form of humic acid and Pseudanabaena catenata cyanobacterial growth supernatant were both found to enhance sorption interactions of Sr-90 with brucite. The effect of humic acid was pH dependent and appeared to control both sorption and desorption behaviour at pH 11.5. Uranium oxides had the most significant effect on controlling Sr-90 and Cs-137 sorption-desorption behaviour. In this work X-Ray Absorption Spectroscopy (XAS) showed that 90Sr sorbed strongly to both uranium oxides as a bidentate inner-sphere complex. Humic acid did not appear to alter the interaction of Sr-90 with UO2. For Cs-137 there was a significant, reversible interaction with both oxides, although the interaction was far stronger with UO3. Successful detection of stable Sr and Cs isotopes on uranium oxides was achieved with Laser Induced Breakdown Spectroscopy (LIBS).
66

Oceňování nemovitostí

Pröschl, Petr January 2006 (has links)
Teoreticko-metodologická část: Základní pojmy při oceňování nemovitostí, metody tržního oceňování nemovitostí, oceňování nemovitostí podle cenových předpisů. Aplikační část: Administrativní ocenění rodinného domu s příslušenstvím a pozemky, popis trhu s nemovitostmi a ocenění nebytového prostoru porovnávací metodou. Součástí administrativního ocenění je nález, popis jednotlivých oceňovaných objektů, jejich výměra, hodnocení a ocenění. V závěru shrnutí dosažených výsledků, porovnání administrativního a tržního ocenění nemovitostí.
67

Finanční analýza společnosti Envi-pur, s r.o.

Hnojna, Pavel January 2007 (has links)
Teoretická část práce vysvětluje podstatu finanční analýzy a její metody, obsahem praktické části je pak finanční analýza společnosti Envi-pur, s r. o. Práce obsahuje např. poměrové ukazatele, Du Pontův rozklad rentability a modely pro posouzení finančního zdraví.
68

Processus engagés dans la rémanence, au niveau du compartiment atmosphérique, des radionucléides artificiels antérieurement déposés

Piga, Damien 08 December 2010 (has links) (PDF)
Les stations atmosphériques de l'observatoire permanent de la radioactivité dans l'environnement mesurent depuis 1959 les niveaux d'activité de radionucléides naturels et artificiels dans les aérosols. Aujourd'hui, le Cs-137 (30.07 ans), radionucléide artificiel issu des essais nucléaires atmosphériques et de divers accidents, est encore mesuré, à l'état de traces dans les basses couches de l'atmosphère, bien qu'il n'existe plus de rejet significatif. Cette étude s'est intéressée à identifier et caractériser les processus qui expliquent sa rémanence. Les territoires fortement impactés par les retombées de l'accident de Tchernobyl sont apparus les principaux contributeurs à la rémanence atmosphérique du Cs-137 dans les aérosols prélevés en France. Dans ces régions, les incendies de forêt constituent le processus de remise en suspension du Cs-137 le plus significatif durant la saison sèche et à l'origine d'épisodes de transport longue distance. Il est estimé qu'annuellement de l'ordre de 1013 Bq de Cs-137 sont réintroduits dans l'atmosphère par ce processus. En relation avec de fortes augmentations de la masse totale de particules en suspension, le Sahara est la seconde région contribuant à la rémanence du Cs-137 dans le compartiment atmosphérique au travers d'épisodes de transport de poussières sahariennes. Il est estimé que l'ensemble de ces évènements contribue en moyenne pour 1/3 du bruit de fond ambiant en Cs-137 à l'échelle de la France. Le dernier processus identifié est l'utilisation de bois comme moyen de chauffage durant l'hiver. Bien que le facteur d'émission de ce processus soit faible, l'étendue spatiale des régions sources et les quantités utilisées durant l'hiver font de ce processus un terme source significatif au regard des niveaux moyens à l'état de traces. A l'échelle de la France, de l'ordre de 1011 Bq de Cs- 137 sont réintroduits dans l'atmosphère par ce processus. Durant cette saison, la diminution des conditions de ventilation dans les basses couches de l'atmosphère entraîne une élévation du niveau moyen tandis que les augmentations significatives de l'activité volumique sont dues à un transport longue distance en provenance de l'est de l'Europe.
69

Atmospheric Production and Transport of Cosmogenic <sup>7</sup>Be and <sup>10</sup>Be

Kulan, Abdulhadi January 2007 (has links)
<p>This thesis deals with the atmospheric distribution of the cosmogenic isotopes <sup>7</sup>Be (half-life 53 days) and <sup>10</sup>Be (half-life 1.51 million years) as well as the anthropogenic isotope <sup>137</sup>Cs (half-life 30 years) in aerosols and precipitation. Samples covering continuous or selected parts of the period 1972-2005 in Sweden and Europe are evaluated with respect to production, air mass transport and fallout processes. Such information is valuable in assessing the potential of these isotopes as indicators of air mass mixing and solar modulation factors that affect climate change. The results of <sup>7</sup>Be and <sup>10</sup>Be show seasonal variability and an 11-year cyclic pattern which is anti-correlated with the solar activity. Variations in seasonal trends of <sup>7</sup>Be and <sup>137</sup>Cs in aerosols during the post- and pre-Chernobyl period reflect tropospheric influence from <sup>137</sup>Cs-heavily contaminated regions. A clear latitude dependence is observed in our beryllium isotope data where highest fallout is found in mid-latitudes compared to high and low latitude regions in the Northern hemisphere. This pattern reflects the general air mass circulation in the troposphere. However, stratospheric air mass influence was also identified in mainly single events and through tropopause folding during spring-summer seasons. The ratio of <sup>10</sup>Be/<sup>7</sup>Be is used to estimate effects of air mass transport on production signal. The results show ratios between 1 and 3, much higher than the theoretically predicted value (0.6) in the atmosphere, which suggests contribution from <sup>7</sup>Be-depleted (old) air masses. The relationship between monthly <sup>7</sup>Be atmospheric activity and Total Fractional Cloud Cover (TFCC), collected from satellite imagery, over Sweden for the years (1991-2000) indicates a negative seasonal correlation. This observation can be related to depletion of aerosol from the atmosphere due to trapping in clouds. </p>
70

Atmospheric Production and Transport of Cosmogenic 7Be and 10Be

Kulan, Abdulhadi January 2007 (has links)
This thesis deals with the atmospheric distribution of the cosmogenic isotopes 7Be (half-life 53 days) and 10Be (half-life 1.51 million years) as well as the anthropogenic isotope 137Cs (half-life 30 years) in aerosols and precipitation. Samples covering continuous or selected parts of the period 1972-2005 in Sweden and Europe are evaluated with respect to production, air mass transport and fallout processes. Such information is valuable in assessing the potential of these isotopes as indicators of air mass mixing and solar modulation factors that affect climate change. The results of 7Be and 10Be show seasonal variability and an 11-year cyclic pattern which is anti-correlated with the solar activity. Variations in seasonal trends of 7Be and 137Cs in aerosols during the post- and pre-Chernobyl period reflect tropospheric influence from 137Cs-heavily contaminated regions. A clear latitude dependence is observed in our beryllium isotope data where highest fallout is found in mid-latitudes compared to high and low latitude regions in the Northern hemisphere. This pattern reflects the general air mass circulation in the troposphere. However, stratospheric air mass influence was also identified in mainly single events and through tropopause folding during spring-summer seasons. The ratio of 10Be/7Be is used to estimate effects of air mass transport on production signal. The results show ratios between 1 and 3, much higher than the theoretically predicted value (0.6) in the atmosphere, which suggests contribution from 7Be-depleted (old) air masses. The relationship between monthly 7Be atmospheric activity and Total Fractional Cloud Cover (TFCC), collected from satellite imagery, over Sweden for the years (1991-2000) indicates a negative seasonal correlation. This observation can be related to depletion of aerosol from the atmosphere due to trapping in clouds.

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