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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.
531

The midwife´s dialogue about alcohol in a lifecycle perspective with both parents-to-be

Högberg, Hjördis January 2016 (has links)
Alcohol use during pregnancy can damage the fetus. Midwives at antenatal care (ANC) screen pregnant women for risk drinking in early pregnancy. There are however, no routines involving both parents-to-be in a dialogue about alcohol. The aim of this thesis is to investigate alcohol use among pregnant women and their partners and to evaluate a method for midwives’ dialogue about alcohol in a life cycle perspective with both parents-to-be. Study I was a quasi-experiment within ANC. An intervention group (IG) received counseling with the midwife about alcohol use. The IG (238 couples) and a comparison group (271 couples) filled out questionnaires in early and in late pregnancy about alcohol use and support for an alcohol-free pregnancy. Study II was a cross-sectional study where 444 partners of pregnant women filled out a questionnaire at ANC about alcohol use, motives for decreased drinking and their perception about the midwives’ counseling about alcohol. Alcohol consumption was low among the pregnant women. One third (30 %) had decreased alcohol use before pregnancy and 90% stopped drinking after pregnancy confirmation. Of the partners, 24 % decreased alcohol use before pregnancy and 40 % decreased during pregnancy. Around 90 % of the women received support for an alcohol-free pregnancy, compared to 37 % of the partners. Twenty per cent of partners and 25 % of pregnant women reported alcoholism in their family. Partners who had alcoholism in the family drank more than partners without this experience. A majority, 95 %, of the partners in study II used alcohol, 29 % were binge drinking on a normal drinking day and 74 % were binge drinking occasionally. Most partners appreciated the counseling about alcohol and reported various motives for decreased alcohol consumption. Many pregnant women and partners decreased alcohol consumption in transition to parenthood, which is a crucial time for changing alcohol-drinking patterns. Involving both parents-to-be in counseling about alcohol restrictions during pregnancy may be a useful health promotion strategy.
532

Quantifying the sustainability of the built environment : the development of a complete environmental life cycle assessment tool

Van Noordwyk, Arina 03 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Sustainability is becoming an increasingly important aspect in all facets of engineering. It is in particular an important consideration in the structural engineering industry, due to the prominence of the negative impact this industry has on the environment, both on a national and international scale. The problem, however, is that sustainability is a mostly unknown and highly debated topic. It is not only difficult to quantify, but even difficult just to define. In the field of structural engineering it is an especially difficult task to consider sustainability. It is still a very new field of research and difficult to apply. It is therefore important that continued research be done in order for there to be a better understanding of how sustainability should be considered and applied in the context of structures. In an attempt to assess the environmental impact of building structures, there are two basic approaches that are followed. The first, the application-oriented method, is a simple, points-based system. The second, the analysis-oriented method, makes use of detailed indices and factors to quantify the impact. This study aims to develop an analysis-oriented method, specifically designed for the complete life cycle of buildings in the South African environment. This is accomplished by continuing the work that was started by Brewis (2011), and continued by Brits (2012). Brewis developed the approach for the pre-use phase, while Brits developed the approach for the end-of-life phase. Both focussed their application on low-cost housing development. However, the approach is defined for the use of the analysis of a building envelope. The details of developing the environmental life cycle assessment (LCA), as well as the approaches for the pre-use phase and the end-of life phase are discussed in Chapter 3. The study develops the use phase of the proposed environmental life cycle assessment for buildings in Chapter 4. It discusses in detail the two main components of the use phase, namely maintenance and operation. While maintenance is concerned with the replacement of building materials in the structure, the operation component is concerned with the energy needs during the use phase. It is determined that the energy use that is directly related to the building envelope is the energy required for the space heating and cooling of the building. This is due to the fact that the thermal properties of the building envelope influence the thermal environment within the building, and thereby impact the use of energy to regulate that thermal environment. In order to make the most use of both of these components within the application of the proposed LCA, it was decided to model a residential building structure that uses consistent energy to regulate the thermal environment within the structure. However, it is not only the objective to use the proposed LCA as an assessment tool, but also as a comparative and optimisation tool. Therefore one component, the external walls, was selected as a variable component. This component was varied to form a total of nine different buildings. These nine buildings were then used in a comparative study in order to try to determine an optimum choice of external walling system, based on the results of the environmental impacts determined in the LCA. It is also used to try to explain exactly how and to what extent the external walling system contributes to the environmental impact, and what useful application value we can gain from this knowledge. The results showed that a minor increase in the materials impact (due to attempts to improve the thermal capacity of the external walls) were in most cases countered by a decrease in the energy impact, which in seven of the eight alternative external walling systems led to a net decrease in environmental impact (EI) categories one to four. It was also found that with the increase of the R-value of the external walling systems, the environmental impact of the building steadily decreased, in terms of four of the five impact categories. The only exception to these trends was found in the fifth impact category: waste generation. The reason for this is the fact that energy impact in this environmental impact category is negligible, and therefore does not contribute much to the net change in environmental impact. / AFRIKAANSE OPSOMMING: Die belangrikheid van volhoubaarheid neem al hoe meer toe in alle aspekte van ingenieurswese. In die industrie van struktuuringenieurswese is dit van besonderse belang as gevolg van die prominente negatiewe impak van hierdie industrie op die omgewing, op beide ’n nasionale en internasionale skaal. Die probleem is egter dat volhoubaarheid nog meestal gesien word as ʼn onderwerp wat onbekend en hoogs debatteerbaar is. Dit is nie net moeilik om te kwantifiseer nie, maar selfs moeilik om dit net te definieer. In struktuuringenieurswese is dit veral ʼn moeilike taak om volhoubaarheid in ag te neem. Dit is nog ʼn baie jong studieveld wat moeilik is om toe te pas. Dit is dus van uiterse belang dat verdere navorsing gedoen word sodat daar ʼn beter begrip kan wees van hoe volhoubaarheid op die lewensiklus van strukture toegepas kan word. In 'n poging om die omgewingsimpak van die geboustrukture te evalueer, is daar twee basiese benaderings wat gevolg kan word. Die eerste, die toepassingsgeoriënteerde metode, is 'n eenvoudige, punte-gebaseerde stelsel. Die tweede, die analise-georiënteerde metode maak gebruik van gedetailleerde indekse en faktore om die omgewingsimpak te kwantifiseer. Hierdie studie beoog om 'n analise-georiënteerde metode te ontwikkel, wat spesifiek ontwerp is vir die analise van die volledige lewensiklus van geboue in die Suid-Afrikaanse omgewing. Dit word gedoen deur die voortsetting van die werk wat begin is deur Brewis (2011), en voortgesit is deur Brits (2012). Brewis het die benadering vir die eerste fase (voor-gebruik) ontwikkel, terwyl Brits die benadering vir die finale fase (einde-van-lewe) ontwikkel het. Beide het die fokus van hul toepassings geplaas op lae-koste behuising. Die benaderings is egter gedefinieer vir die algemene analise van ʼn gebou se raamwerk. Die besonderhede van die ontwikkeling van die omgewingslewensiklus analise (OLA), asook die benaderings vir die eerste en finale fases, word in Hoofstuk 3 bespreek. Die studie ontwikkel die gebruiksfase van die voorgestelde omgewingslewensiklus analise vir geboue in Hoofstuk 4. Dit bespreek die twee hoofkomponente van die gebruiksfase, naamlik die instandhouding en bedryf. Terwyl instandhouding gemoeid is met die vervanging van boumateriale in die struktuur, is die bedryfskomponent gemoeid met die energie behoeftes tydens die gebruiksfase. Dit word bepaal dat die energie verbruik wat ʼn direkte verband het met die gebou se raamwerk, die energie is wat nodig is vir die verhitting en verkoeling van die gebou. Dit is te danke aan die feit dat die termiese eienskappe van die gebou se raamwerk die termiese omgewing binne die gebou beïnvloed, en sodoende 'n impak het op die energie wat benodig word om die temperatuur te reguleer. In ʼn poging om die spektrum van die voorgestelde OLA ten volle te benut, is dit besluit om die toepassing daarvan te illustreer op 'n residensiële gebou wat van konsekwente energieverbruik gebruik maak om die termiese omgewing binne die gebou te reguleer. Dit is egter nie net die doel om die voorgestelde OLA te gebruik as 'n assesseringsinstrument nie, maar ook om die OLA se funksie as ’n vergelykende en optimaliseringshulpmiddel te illustreer. Dus is een komponent, die eksterne mure, gekies as 'n veranderlike komponent. Hierdie komponent is gewissel om 'n totaal van nege verskillende geboue te vorm. Hierdie nege geboue is gebruik in 'n vergelykende studie in 'n poging om 'n optimale keuse van eksterne mure te bepaal, gebaseer op die resultate van die omgewingsimpak wat in die OLA te bepaal is. Dit word ook gebruik om te probeer om te verduidelik presies hoe en tot watter mate die eksterne mure bydra by tot die omgewingsimpak, en watter nuttige toepassingswaarde geput kan word uit hierdie kennis. Die resultate het getoon dat 'n toename in die materiaal impak (weens pogings om die termiese kapasiteit van die eksterne mure te verbeter) in die meeste gevalle teengewerk is deur 'n afname in die energie impak. In sewe van die agt alternatiewe eksterne muurstelsels het dit gelei tot 'n netto afname in omgewingsimpak vir kategorieë een tot vier. Dit is ook gevind dat die omgewingsimpak van die gebou stelselmatig gedaal het met die toename van die Rwaarde van die eksterne muurstelsels, ook in terme van kategorieë een tot vier. Die enigste uitsondering op hierdie tendense is gevind in die vyfde impak kategorie: die afval wat gegenereer word. Die feit dat die effek van energie verbruik gering is in hierdie omgewingsimpak kategorie, lei tot die feit dat dit nie veel bydra tot die netto verandering in die omgewingsimpak nie.
533

An automotive interior lighting application using white light-emitting diodes

Solomon, Ramzi, Pillay, P., Sebitosi, A.B. January 2008 (has links)
Thesis (MScEng (Department of Electrical Engineering))--University of Cape Town, 2008. / Energy drives technological societies. Developing countries such as South Africa are caught between the desperate need for economic growth and the emerging obligations to the environment. Efficient technologies can be used to mitigate the impact of these seemingly conflicting requirements in urban and rural environments. In this thesis the commercially available white light-emitting diode (LED) with its inherent efficiency, longevity and mechanical strength, is used to show, that success in energy efficiency can be obtained. Two cases are used to illustrate the need for efficient demand-side technology: the electricity shortages of the Western Cape Province in South Africa and a white LED pilot project in Namulonge, Uganda. The Namulonge Solar-Home System (SHS) is analyzed with the intention of creating a more acceptable general lighting solution. The concept of appropriateness through self-determination is discussed within the context of location-specific information integrated into a design procedure. The major thrust and contribution of this thesis, however, is the design of an interior luminaire for Golden Arrow Bus Services (GABS). This is in part based on the hypothesis that application-specific information will lead to implementation and human-needs success, and is researched, designed, fabricated and then laboratory tested. The biggest challenge to be overcome was the spatial light distribution of the LED array. Thus non-imaging optical lens design became the main focus of this project as it held the key to utilizing available light while conserving the light-systems energy. Circular Fresnel and Linear Fresnel (an adaptation of the concentric design) lenses were designed. Electrical, mechanical and thermal aspects of design are also detailed. Far-field, horizontal plane detection over the specified area is used to best gain the uniformity of distribution. The four criteria namely luminance, illuminance, intensity and étendue (collection efficiency), against which each design and focal length iv configuration is compared to, are extensively explored and eventually lead to a final design. In the first designs, the area of the spatial distribution between 50% and 80% of its relative intensity is collimated. The Hybrid Circular Fresnel and Hybrid Linear Fresnel lenses now redirects the relative intensity in two areas, from 50% to 70% (creating parallel rays) and then from 70% to 100% (away from the central axis), renders a distinct difference is spatial uniformity and a reduction in the peak and offaxis located intensity. All four criteria are met, with a minor adjustment of configuration within the bus internal luminaire spacing, with the hybrid designs. It is proposed that GABS employ polished designs of the Hybrid Circular Fresnel, in any of the configurations, which have collection efficiencies ranging between 64.8% and 78.3%. / Sponsored by the Centre for Renewable and Sustainable Energy Studies, Stellenbosch University
534

Product orientation of environmental work - barriers & incentives

Zackrisson, Mats January 2009 (has links)
<p><em>Abstract</em></p><p>The research behind this licentiate is spread out over a decade of intensive development of environmental work in industry. A 1998 survey of Swedish companies with newly installed environmental management systems (EMS) concluded that such systems need more product-orientation. Data collected by companies as part of the process of creating their EMS between 1996-2001 offered further evidence that it is environmentally justified to seek improvements in the materials selection, use and disposal phases of products, i.e., to make the environmental improvement work more product-orientated. In a EU-funded project carried out between 2004-2006 it was demonstrated that developing an environmental product declaration could be a cost-effective product-oriented environmental action even for smaller companies.</p><p>This licentiate thesis relates to methods for companies to orientate their environmental work on their products. In particular, it examines experience and provides insights on the possibilities for companies, including small ones, to use life cycle assessment in product development in order to design products with an environmental performance well above legal compliance.</p><p>It is difficult to give general recommendations to companies about their environmental work because each company has its own unique business idea, customers, work culture, stakeholders etc. Nevertheless, the main findings of the licentiate thesis can be summed up in the following recommendations for, say, a small company in Europe without much previous experience of environmental work:</p><p>§  Focus your environmental work on your products because you will accomplish more environmentally and the chance of profiting economically will motivate your personnel;</p><p>§  Consider doing a life cycle assessment, LCA, on a strategically chosen product in order to learn more about your products and how to improve their environmental performance;</p><p>§  Do not expect to find a general market demand for green products; start a dialogue with your best customers in order to create the demand;</p><p>§  Engage an LCA specialist to do the LCA and work together with your personnel to interpret the results and generate improvement ideas;</p><p>§  If your customers demand that you install an environmental management system, ask them if they would not prefer to receive an environmental product declaration on the particular product they are interested in, and a chance to discuss how its environmental performance can be improved.</p>
535

Environmental assessment of the urban environment

Forsberg, Anna January 2003 (has links)
<p>This thesis gives a systematic description of theEnvironmental Load Profile (ELP), an environmental assessmenttool developed for the urban environment. The purpose of thework was to improve the stringency of the system boundaries andfunctional units of the tool. This was achieved by putting theELP structure in the context of Life Cycle Assessment (LCA)with a special emphasis on system boundaries. To create animproved scientific base for the ELP, a comparative study wasconducted using an evaluative framework for conceptual andanalytical approaches. Here, the ELP tool is compared with foursimilar environmental assessment tools for the builtenvironment.</p><p>Since, energy use in the operation phase is an importantfactor for the overall environmental performance of buildings,a sensitivity analysis was performed to investigate how theselection of heat and electricity mix affects the results of anenvironmental assessment of buildings. Four modes ofelectricity production and two modes of heat production wereapplied on three buildings with different technical systems intheir heat supply. The results show that the choice ofelectricity mix has a great influence on the outcome of anenvironmental assessment (EA) and it is suggested that both anaverage and marginal electricity mix should be applied inEA´s of the built environment. Further, it is argued thatconsequences of assumptions made should be explicitlycommunicated in the EA report, to allow the decision-makersrather than the analysts to make the final evaluation.</p><p>The ELP is primarily developed to follow up theenvironmental goal‘twice as good’and assess theenvironmental performance of Hammarby Sjöstad, a newcity-district in southern Stockholm. The city-district is builtas a continuation of the inner Stockholm and the first part ofthe project, called Sickla Udde, is nearly finished. The ELPtool was applied in a first case study to answer the questionof how far Sickla Udde has reached in achieving the goal. Theassessment indicates that compared to a reference districtbased on the technology used in 1990, the environmentalperformance of Sickla Udde has reached the goal‘twice asgood’for some environmental load categories and 30percent for others. Although these findings are preliminary,they indicate a development in the right direction. Measurestaken contributing to largest environmental improvements are: amore efficient energy production (improved district heating)and use (e.g. lower U-values in the buildings, energy efficientappliances, heat exchange of ventilation air) and improvedsewage treatment. The results also demonstrate that theenvironmental load from domestic transports can be of the samemagnitude as from the buildings situated within thecity-district. Hence, resources spent to decrease environmentalload in the planning process should primarily be divoted toimproving domestic transportation systems and on optimising theoperational phase of the buildings.</p><p><b>Keywords:</b>environmental assessment, urban district,environmental load profile, Hammarby Sjöstad, life cycleassessment, LCA, environmental management, builtenvironment</p>
536

Environmental Systems Analysis Tools as Decision-Support in Municipal Solid Waste Management : LCA in Sweden, Estonia and Lithuania

Johnson, Amanda January 2013 (has links)
In order to deal with the mounting issue of Municipal Solid Waste (MSW) in a way that is in line with sustainable development and Integrated Solid Waste Management (ISWM) a systems approach is necessary.This approach can practically be integrated into the MSW decision-making process through Life Cycle Thinking(LCT) and environmental systems analysis tools such as Life Cycle Assessment (LCA). This paper is written within the context of the RECO Baltic 21 Tech (RB21T) project which aims to improve waste management practices in 12 countries in the Baltic Sea Region. The main aim of this paper is to investigate the extent to which LCA is used as decision-support in MSW management in Sweden, Estonia and Lithuania. The use of LCA is examined on a national level as well as on a local or regional level based on relevant literature and a set of interviews conducted in each country. According to the results the use of LCA as decision-support in MSW management is very limited in Estonia and Lithuania whilst it is already a well-established tool in Sweden. Most of the LCA efforts in the Baltic States have been conducted in connection with foreign projects and investments,such as RB21T. Although an actual LCA might not always be applied in Sweden, LCT is prevalent in MSW management both on a national and local level. In order for LCA to be better integrated into MSW management this paper argues that there is a need for increased knowledge, data, more user-friendly LCA-tools andstrengthening regional partnerships for further transfer of knowledge between countries.
537

Integrering av ekosystemtjänsbegreppet i LCA-metodik : Kartläggning av möjligheter genom en fallstudie på pelletsproduktion / Integrating the Ecosystem-Service Concept into LCA-methodology : Mapping of possibilities through a case study on pellet production

Nordin, Emma January 2014 (has links)
De nyttor som människan får direkt och indirekt från ekosystemen kallas ekosystemtjänster. Mänsklighetens påverkan på ekosystemen idag leder till degradering av tjänsterna och då mänskligheten ytterst är beroende av vad de tillför, är bevarandet av dessa tjänster viktig. Livscykelanalys, LCA, är ett väletablerat verktyg som används för att fastställa miljöpåverkan från olika produktprocesser men få ekosystemtjänster beaktas i LCA. Det finns därför ett behov av att vidare undersöka och utveckla möjligheterna att med livscykelbaserade metoder analysera påverkan på ekosystemtjänster. Huvudsyftet med denna studie har varit att undersöka om det är möjligt att integrera ekosystemtjänstbegreppet i LCA-metodik. Detta har kartlagts med hjälp av en fallstudie på pelletsproduktion, som bl.a. identifierat berörda ekosystemtjänster och möjligheten att kvantifiera dem, vilka ekosystemtjänster som går att studera med LCA idag samt möjliga sätt att analysera påverkan på ekosystemtjänster med LCA. Ett delmål har varit att grundligt beskriva både ekosystemtjänster och LCA samt aspekter som kan koppla ihop dessa områden. En omfattande litteraturstudie och en LCA modellering rörande pelletsproduktion utgjorde grund för arbetet. I dagsläget är det inte möjligt att integrera ekosystemtjänstbegreppet i LCA-metodiken med undantag för de fåtal ekosystemtjänster som i LCA-metodiken redan beaktas i viss utsträckning. Det stora hindret är att det inte finns någon fullständig och enhetlig metodik för kartläggning, klassificering och kvantifiering av ekosystemtjänsterna, vilket anses nödvändigt för att kunna analysera påverkan på dem. Ett stort antal ekosystemtjänster såsom klimatreglering, näringsflöden, biodiversitet och rekreation kan kopplas till pelletsproduktion men påverkan på dem är inte möjlig att fullt ut analysera med LCA. Detta illustreras av LCA-modelleringen av pelletsproduktion där endast påverkan på tjänsterna förnybara energikällor och vattenanvändning ingår. Då kunskapen rörande olika ekosystemtjänster skiljer sig mycket åt varierar förutsättningarna för att inkludera dem i LCA-metodiken. Befintliga tillvägagångssätt för att försöka analysera påverkan på ekosystemtjänster med hjälp av LCA föreslår nya miljöpåverkanskategorier och samlandet av tjänsterna i gemensamma enheter såsom exergi och solekvivalenter. Metoderna är dock begränsade och täcker inte in ekosystemtjänsterna på ett fullgott sätt. Mer forskning behövs för att bättre utveckla tillvägagångsätten för analys av påverkan på ekosystemtjänster genom LCA. / The profits humankind obtains directly and indirectly from ecosystems are called ecosystem services. The impact human activities have on ecosystems lead to degradation of the ecosystem services and since humankind fully depends on what the ecosystems provide, the preservation of these services is crucial. Lifecycle assessment, LCA, is a well-established tool used to assess environmental impacts from different product processes but few ecosystem services are considered. Thus, there is a need to study and develop the possibilities to analyze ecosystem services through LCA based methods. The project aimed to determine whether it is possible to integrate the ecosystem-service concept into LCA-methodology. A case study on pellet production was carried out to identify relevant ecosystem services and the possibilities to quantify them, which ecosystem services that could be analyzed in LCA today and also available approaches to study impacts on ecosystem services with LCA. An intermediate goal was to present a comprehensive description of both ecosystem services and LCA and to map common aspects that connect the two fields. The analysis was based on a comprehensive literature study, and a specific LCA-modeling of pellet production. At present, it is not possible to integrate the ecosystem-service concept into LCA-methodology, except for the few ecosystem services that to some extent already are covered in the methodology. The main obstacle is the lack of coherent approaches to map, classify, and foremost quantify ecosystem services, which is considered crucial for analyzing the impact on them. A large number of ecosystem services such as climate regulation, nutrient cycling, biodiversity and recreation can be influenced by pellet production but it is not possible to fully analyze these impacts with LCA. This is illustrated by the LCA-modeling on pellet production where only impacts on the services renewable resources and water use could be included. The possibilities to analyze ecosystem services within LCA vary due to the variation in knowledge about certain services. The present approaches for analyzing more services with LCA propose new environmental impact categories an aggregation of services into common units such as exergy and solar equivalents. The methods are limited due to the fact that they are not able to cover the diversity of the services. More research is needed to develop the approaches for analyzing impacts on ecosystem services through LCA.
538

Perceptions of quality teaching at a business school : implications for management / Claus Kempen

Kempen, Claus January 2014 (has links)
The general purpose this study has been to determine the perception of MBA students on quality lecturing. Business schools are concerned about how learners evaluate the lecturing experiences in order to monitor the quality of the lecturing. Student evaluations are assumed to mirror relative stable views which hold implications for how tertiary institutions act upon and reward the educational practices of lecturers. It is evident from prior research that broad reaching claims concerning student satisfaction cover large alternatives in terms of a construct being evaluated. Links between what is measured, and how this information should be utilised, are not always well-defined. Previous studies suggest that student satisfaction and perception is a multifaceted concept consisting of several complex dimensions. The true muscle of lecturing is crucial leadership ability. It is not just a lecture or a presentation. Lecturing is a set of skills. It is not just about a gift. It is a set of practices that should be rehearsed, mastered and delivered. A lecturer will certainly not deliver a faultless lecture, but might bring an influential and current lecture. The skill set of lecturing is both a skill and a discipline. A lecturer should learn and practices the discipline; then the skill will be conquered. Everyone can be a powerful and skillful presenter, but it will take time, rehearsal and vigor to overcome mediocrity. The management of business schools should comprehend the importance of quality lecturing. Without emphasis on lecturing, the perceived quality of a business school could be misconceived by students. Quality lecturing should always be a focus point and the emphasis on improved effectiveness by management. / MBA, North-West University, Potchefstroom Campus, 2014
539

Företagslivscykelns påverkan på nätverksstrukturen för svenska riskkapitalbolag. : - En kvantitativ studie ur ett nätverksperspektiv

Matsson, Johan, Olsson, Maria January 2013 (has links)
Riskkapitalbranschen är en växande bransch i Sverige och både en viktig finansiär samt kunskapskälla för både nystartade företag och företag med ambition att växa sig stora och internationella. Beroende på vart i livscykeln ett företag befinner sig står de inför olika utmaningar och behöver hjälp med olika saker, en hjälp som riskkapitalbolagen kan bidra med. Studien syftar till att generera kunskap om svenska riskkapitalbolag och bidra med kunskap till den kunskapslucka vi observerat inom ämnet. Studien fokuserar på nätverksstrukturen bland de företag som svenska riskkapitalbolag har valt att investera i samt skillnaden i nätversstrukturen beroende på vart i livscykeln företagen befinner sig. Med en kvantitativ metod har vi, genom att identifiera relationerna mellan de företag som riskkapitalbolagen investerar i, kartlagt nätverken mellan de olika aktörerna. Populationen bestod av svenska riskkapitalbolag och urvalet skedde strategiskt utifrån vad olika källor ansåg vara de två största och mest framgångsrika riskkapitalbolagen i norden. Med hjälp av excel, Minitab 16 samt UCINET 6 har vi kunnat illustrera de olika nätverken samt kunnat analysera dem i form av centralitet och densitet på nätverksnivå samt jämfört de olika relationerna. Studiens resultat visar på att riskkapitalbolagen är med och löser de olika fasernas karakteristiska utmaningar med hjälp av hur de strukturerar nätverken bland de företag de väljer att investera i. Detta betyder således att nätverkets struktur är viktig för de olika företagens framgång. / This study is aiming of contributing with information about Swedish Venture Capital firms, which we have found is missing. By answering research questions like how the networks of the Venture Capital firms are structured and if the network structure has different settings depending on which phases in the life cycle the invested companies are located. We focus on the Swedish venture capital firms and their networks. The network structure is analyzed out of centrality, density and number of relationships. In UCINET 6 we were able to make illustrations of our networks and to calculate the values of our variables on network level. In the statistical program Minitab, we calculated the mean value and standard deviation for the venture capitals’ invested companies’ phases.
540

Comparative life cycle impact assessment of a battery electric and a conventional powertrains for a passenger transport ferryboat : A case study of the entire integrated system for vessel propulsion

Mihaylov, Veselin January 2014 (has links)
This master thesis represents a life cycle impact assessment of a state of the art electrically driven power train. It is expected to be installed in a diesel engine passenger ferry boat, currently transporting passengers in downtown Stockholm archipelago. The assessment has a comparative character in between the currently operating and the new power train in order to differentiate and recognize which of the two propulsion options is the environmentally preferable choice. The scope of the study is directed towards the thorough examination of both power trains so that it can represent most closely the two specific technological cases. Studied and assessed were the three main life cycle phases of each power train – raw materials acquisition and manufacturing, use phase and end of life phase. The fundament of the study involved creating environmental models for each and every component of the drive trains, the propulsion fuel and energy used, and the services related to waste treatment in the last phase of their functional life. The environmental models were later used to build live cycle inventories that served to derive the respectful impact from the item analyzed. The data used to model the battery electric power train was provided directly from the manufacturer, where the end of life procedures carried out were assumed where possible. The main battery pack for the electric power train was not modeled in terms of  end of life procedures due to insufficiency of information. Almost no generic information was available to model the diesel engine and it was calculated by creating auxiliary simplified cad models. The rest of the data required to achieve an environmental inventory regarding the power train was available from a subcontractor. Both studied options were modeled with allocation approach that includes the avoided production of materials at the waste treatment stage where there was sufficient information to do that. There was none to model the main battery packs avoided production which is a major component of the battery electric system. To model the use phase of the diesel engine power train, research data regarding combustion emissions and waterborne emissions was utilized. A number of electricity mix models were applied to create a sensitivity analysis of the operation phase of the battery electric power train. Chosen for baseline scenarios simulating the use phases of both power trains are use of Nordel market electricity mix and the combustion of low sulfur diesel with five volumetric percent rape methyl ester additive. For the purposes of the assessment eighteen midpoint impact indicators were used to cover the areas of global warming potential, human health and quality of eco systems. The results from the study show that the estimated impact from both power trains is small enough to have almost no influence on the results from the two baseline scenarios. Based on this it was concluded that for future research of similar cases either generic information can be used or a cut-off can be applied. After the assessment, more environmentally favorable was estimated the diesel engine power train because of the large burdens from the battery manufacturing in the battery electric option. Further assessment determined that the diesel engine power train again is less environmentally intensive than the battery electric with the main battery burdens excluded. In the overall life cycle impact assessment both power train showed different results in the different impact categories, which could not place a definitive propulsion option of choice. The conclusions from the analysis are that the diesel engine power train causes higher impact in the categories related to global warming, fossil depletion and in most ecosystems quality indicators. The battery electric version in its base line scenario, on the other hand, expresses higher impact in categories related to human health and in the remaining eco system quality midpoint-scores.

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