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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.
31

Procedimiento de selección de subcontratistas en proyectos de carreteras en el Perú mediante el análisis multicriterio / Selection procedure for subcontractors in the roads projects in Peru through multi-criteria analysis

Casanova Vise, Franco Enrique, Diaz Mendoza, Renato Fabriccio 09 July 2020 (has links)
Las elecciones de los subcontratistas en los proyectos de carreteras del Perú no poseen un procedimiento estandarizado, lo cual conlleva a utilizar distintas técnicas insuficientes para la elección optima del subcontratista. La presente investigación se enfoca en disminuir los sobrecostos ocasionados por los subcontratistas, seleccionando de forma objetiva al subcontratista más adecuado para realizar el proyecto, estableciendo un procedimiento que emplea el análisis multicriterio. Para ello, se aplica este procedimiento a 3 proyectos de carreteras obteniendo una comparación entre el subcontratista seleccionado para la partida de señalización y el obtenido a través de los métodos multicriterio. Para obtener el subcontratista a través de la metodología es necesario realizar 4 procedimientos: El primero, consta en identificar los criterios más importantes para el proyecto y asignar una incidencia con la metodología del proceso analítico jerárquico (AHP). El segundo, reside en recopilar los datos de los subcontratistas postores basado en los criterios seleccionados y evaluarlos. El tercero, se basa en procesar los datos con el Método de organización de clasificación de preferencias para la evaluación de enriquecimiento (PROMETHEE). Por último, con los datos procesados se elabora un ranking de los subcontratistas y se selecciona el de mayor puntaje. La información obtenida de la experiencia realizada se sintetiza en un procedimiento que describe las etapas a seguir para la aplicación del método. / The elections of subcontractors in the road projects of Peru have not been a standardized procedure, which leads to using different techniques that are insufficient for the optimal choice of the subcontractor. The present investigation focuses on reducing the cost overruns caused by subcontractors, selecting objectively the most suitable subcontractor to carry out the project, establishing a procedure that uses multicriteria analysis. Therefore, this procedure is applied to 3 road projects, where a comparison is realized between the subcontractor selected for the works of road signaling and the result through the multicriteria methods. To obtain the subcontractor through the methodology, it is necessary to carry out 4 procedures: The first consists in identifying the most important criterias for the project and giving them an incidence with the methodology of the hierarchical analytical process (AHP). The second one is to collect the data of the bidder subcontractors based on the selected criteria and evaluate them. The third is based on processing the data with the classification method of the functions for the enrichment evaluation (PROMETHEE). Finally, with the data processed, a ranking of the subcontractors is elaborated and the highest score is selected. The information obtained through the experience, is synthesized in a procedure that describes the steps to follow for the application of the method in a road project. / Tesis
32

Sustainability Assessment of Hydrogen Production Techniques in Brazil through Multi-Criteria Analysis

Tapia, Luis Carlos Felix January 2013 (has links)
Current global demands for energy resources along with continuous global population growth have placed natural environments and societies under great stress to fulfill such a need without disrupting economic and social structures. Policy and decision-making processes hold some of the most important keys to allow safe paths for societies towards energy security and safeguard of the environment. Brazil has played a lead role within renewable energy production and use during the last decades, becoming one of the world’s leading producer of sugarcane based ethanol and adapting policies to support renewable energy generation and use. Although it is true that Brazil has historic experience with managing development of renewables and its further integration into the consumer market, there is still a lot to do to impulse new technologies that could further reduce emissions, increase economic stability and social welfare. Throughout this thesis project a sustainability assessment of hydrogen production technologies in Brazil is conducted through Multi-Criteria Analysis. After defining an initial framework for decision-making, options for hydrogen production were reviewed and selected. Options were evaluated and weighted against selected sustainability indicators that fitted the established framework within a weighting matrix. An overall score was obtained after the assessment, which ranked hydrogen production techniques based on renewable energy sources in first place. Final scoring of options was analyzed and concluded that several approaches could be taken in interpreting results and their further integration into policy making. Concluding that selection of the right approach is dependent on the time scale targeted for implementation amongst other multi-disciplinary factors, the use of MCA as an evaluation tool along with overarching sustainability indicators can aid in narrowing uncertainties and providing a clear understanding of the variables surrounding the problem at hand.
33

Feasibility study for expansion of the existing intermodal terminal in Jordbro.

Christidi, Ioulia Christina January 2014 (has links)
Freight transportation changes in the region of Stockholm lead municipalities to the need of finding ways to maintain and empower their current logistics role in the area. These changes are the operation of the future freight port in Norvik near Nynäshamn, the expansion of Stockholm leading to new freight transportation networks, and the extension of the double track line southern to Västerhaninge station. Haninge municipality is willing to keep the interest of existing companies in its land alive and perhaps increase its’ attractiveness by constructing an extension of the terminal in Jordbro. But before proceeding to that step, the municipality wants to investigate whether companies are aware of these changes and furthermore if they have plans for changing their current goods transportation patterns. It is also interested in finding out the factors that companies consider as the most important when they take decisions about their goods transportation plan. That way the municipality knows what is important for companies and can adjust the supply of infrastructure to their demands. The main method used for data collection is designing and conducting a questionnaire and for data analysis it is multi-criteria analysis (MCA). The questionnaire also includes questions about the nature of the company and the current ways of goods transportation. Although the number of responders is quite low, some general conclusions could be made. There are two alternatives competing and multi-criteria analysis leads to the selection of the most suitable one. There are several limitations and assumptions which can be overcome by further future research.
34

Key Considerations When Selecting Environmental Rating System : Decision-Making Analysis from Landlord and Tenant Perspective

Sauchyk, Dzmitry January 2017 (has links)
It is estimated that nearly 100 various environmental product certification rating tools are implemented in the United States construction and real estate industries. Choice of a certain building sustainability measurement tool depends on the specific need for reflection of buildings’ impact on the natural and urban environment as well as its tenants. Selection of the appropriate rating system is a decision-making process performed by the project client (landlord of the building, potential or current tenant) which can be affected by clients’ insufficient knowledge or otherwise be biased. The result of selection decision has significant consequences for the project design, construction process complexity and entire life-cycle of the building. In this work, an effort is made to facilitate decision-making process of best environmental rating alternative selection for a “green building” project. The analytic hierarchy process is used to perform unbiased decision making on the environmental rating selection. The decision process has been evaluated from the landlord and the tenant perspectives. The findings of this study show that for the landlord, it would be enough to be certified with a single-attribute rating that covers only one characteristic of building sustainability and, according to AHP analysis, satisfies all significant landlord’s requirements for the environmental rating system. The main conclusion of the study is that selection of environmental rating is a multicriteria problem that should take into consideration the requirements from landlord and tenant as well as the environmental ratings characteristics but not based on the distinct assessment of the mentioned factors.
35

Investigation of the siting process of Swedish nuclear power plants using GIS / Undersökning av lokaliseringsprocessen av svenska kärnkraftverk med hjälp av GIS

Wollberg, Daniel, Morast, Egil January 2020 (has links)
In order to find the optimal placement for a nuclear power plant (NPP) many different factors have to be taken into consideration. Choosing the wrong location could result in higher construction costs and/or taking avoidable risks. GIS can be used to compare different spatial criteria efficiently. There are currently six nuclear reactors operating in Sweden, producing approximately 40% of the total electricity produced in the country every year. These reactors are divided over three nuclear power plants: Ringhals, Forsmark and Oskarshamn. The objective of this thesis is to evaluate the suitability of existing NPPs location in Sweden according to the current standards and guidelines and find good potential sites for a new hypothetical NPP in Sweden. The thesis is limited to investigate the geographical aspects of siting an NPP, and therefore economic decisions and law restrictions will have less impact on the end result. The methodology of the thesis is in line with International Atomic Energy Agency’s step by step siting procedure that includes a site survey in which candidate areas are derived using a set of exclusionary and avoidance criteria. This is followed by the comparison and ranking of these sites by implementing a suitability analysis in the site selection process to derive potential sites. The site survey process result in a map layer containing the candidate areas that fulfills the spectre of exclusionary and avoidance criteria set by the analyst. The site selection process includes weighting criteria compared to each other using the analytic hierarchy process which is based on the perceived importance of each criterion. The criteria are found in an initial study of available literature. Based on the gathered information, data is collected to execute the analysis in ArcMap. Both vector operations and raster calculations are made to produce the end result map layers. The analysis shows that Forsmark is the most suitable location for an NPP among the existing sites. Neither of the existing sites is considered a candidate site, but that depends heavily on how strict the avoidance criteria is set. Three candidate areas were chosen to be further investigated; Sjötorp, Mariefred and Vanneberga. Between these three Sjötorp was determined to be the most suitable location to site an NPP. One conclusion that can be drawn is that more knowledge in the nuclear power industry and more insight in the weighting part would probably lead to more accurate results. It is hard to know how accurate the model is but it could definitely be used and modified for further studies, either with the same goal in mind or with a different goal and modified criteria. / För att hitta det optimala området för ett kärnkraftverk måste man ta hänsyn till flera kriterier. Fel val av område kan resultera i extra konstruktionskostnader och/eller onödiga säkerhetsrisker. GIS kan användas för att jämföra geografiska kriterier på ett effektivt sätt. Idag finns det sex stycken reaktorer i bruk i Sverige. Dessa producerar ungefär 40% av landets el. Reaktorerna är fördelade på tre stycken anläggningar: Ringhals, Forsmark och Oskarshamn. Syftet med detta arbete är att utvärdera lämpligheten av placeringen av de existerande kärnkraftverken i Sverige i enlighet med nutida standarder och riktlinjer och att hitta bra potentiella områden för ett nytt hypotetiskt kärnkraftverk i Sverige. Arbetet är begränsat till att undersöka de geografiska aspekterna av nyförläggningsprocessen och därmed har ekonomiska beslut och lagrestriktioner mindre påverkan på slutresultatet. Metodiken för arbetet är i linje med IAEAs steg för steg nyförläggningsprocedur som inkluderar en site survey där candidate areas tas fram genom att använda en rad med kriterier för områden som antingen ska exkluderas eller undvikas. Dessa områden jämförs och rankas sedan genom att implementera en suitability analysis i site selection processen för att framhäva potentiella områden. Site survey processen resulterar i ett kartlager med de kandidatområdena som uppfyller spektrumet av kriterier som analytikern har bestämt antingen ska exkluderas eller undvikas. Site selection processen inkluderar att vikta kriterier i förhållande till varandra med hjälp av den så kallade analytic hierarchy process som baseras på den uppfattade vikten av varje kriterium. Kriterierna formuleras efter en initial litteraturstudie. Baserat på den samlade informationen hämtas data för att kunna utföra analysen i ArcMap. Både vektoroperationer och rasterberäkningar utförs för att producera de kartlager som sedan återfinns i slutresultatet. Analysen visar att Forsmark är den bäst lämpade platsen för ett kärnkraftverk utav de områdena där existerande kärnkraft är placerade. Inget av de existerande områdena anses vara ett kandidatområde, men det beror till stor del på hur strikt de kriterier som ska undvikas är satta. Tre kandidatområden valdes för vidare undersökning; Sjötorp, Mariefred och Vanneberga. Av dessa tre ansågs Sjötorp vara det bäst lämpade området för ett kärnkraftverk. En slutsats som kan dras är att djupare kunskap inom kärnkraftsindustrin och mer insikt i viktningen skulle leda till mer exakt resultat. Det är svårt att veta hur exakt modellen är men den skulle definitivt kunna modifieras och användas för framtida studier, antingen med samma slutmål eller med ett annat mål och modifierade kriterier.
36

Smartphone sustainability assessment using multi-criteria analysis and consumer survey

Gedusevs, Janis January 2018 (has links)
Sustainability is a fairly new emerging business concept for manufacturing industry and this thesis will focus on smartphone manufacturing industry. In 2015 there were 1.86 billion smartphone users and it is estimated to increase to 2.87 billion in 2020. Currently the average lifetime of a smartphone is 21 months and According to Consumer Technology Association the technical life expectancy of a smartphone is 4.7 years. The European Commission approximated that from 17–20 kg of electronic waste is produced per person per year and that smartphones are contributors for increase of electronic waste. Also the smartphone manufacturing process has an impact on the people who are involved with manufacturing and resource extraction process.  Related social problems include conflict minerals, issues in manufacturing campuses, health problems and excessive worktimes. There has been suspicion that large manufacturing companies use labour market in areas that have a high risk of poverty or lack of national authority that can protect labour rights. To investigate these emerging issues that has an impact on smartphone manufacturing sustainability, a sustainability ranking criteria for individual smartphones devices and their manufactures was developed. Furthermore, the aim of the research is to develop a ranking system using life cycle perspective and to evaluate sustainability of a smartphones upcycling, recycling, and social aspects. This aim will be accomplished by the following objectives: Develop evaluation system for smartphones using Multi-Criteria Analysis (MCA) to evaluate sustainability; Comparing sustainability of smartphones Fairphone 2, iPhone 7, Samsung Galaxy S7 and LG G5, using developed Multi-Criteria Analysis (MCA); Conducting general sustainability- focused survey about consumer demand for sustainable and ethical electronics. The method used in this research to assess smartphone sustainability was Multi-Criteria Analysis(MCA), based on eco-design trends and three pillars of sustainability, – economic, environmental and social. Eco-design will be supported using EcoDesing Roadmap by Conrad Luttropp and Göran Brohammer. In parallel with MCA method a survey was developed to briefly assess consumer’s behaviour in terms of choosing sustainable electronics. For better understanding about the consumer value on purchase decision, a survey was made considering the technical and sustainable aspects. The results of this survey will be used as indicator. Furthermore, results from this research (Table 1 MCA evaluation results) revealed that majority of chosen smartphones where lacking sustainable products aspects. This MCA ranking system also confirm that for sustainable designed smartphone it is equally important to have well established environmental management system for overall manufacturing process and afterlife of smartphone. Continuing, after conducting deeper analysis with combined results from MCA, survey revealed that general public are willing to pay more for sustainable products, but consumers lack information about the overall manufacturers` sustainability, as well Indicating that communication between manufacturers and consumers are very weak or even one way. The conclusion of the study about Smartphone sustainability assessment using multi-criteria analysis and the consumer survey has provided better understanding about the lack of transparency and complex logistics manufacturing process of smartphone. The lack of qualitative data and transparency from the manufactures side is a major issue that creates lot of uncertainties about smartphone manufacturing process and social issues for workforce that is involved in this manufacturing process.
37

Sustainability Assessment for Small Scale Biogas in Yogyakarta Province, Indonesia

Naihma, Dintani Yudhitya Noorzakiah January 2017 (has links)
The study evaluates sustainability aspects of small scale biogas production in Yogyakarta Province of Indonesia. Growing number of livestock (i.e. cows, sheep, chicken, pigs, and other domestic animals) in the region brings opportunity to produce biogas from livestock manure, leading to improve energy security especially in household, while contributing to renewable energy target which is 31% from Total Primary Energy Demand (TPES) in all sectors by 2050. Biogas potential from cattle, horse, buffalo, pig, sheep, goat, chicken and duck which own by household in all regencies within the province of Yogyakarta (i.e. Bantul, Gunung Kidul, Kulon Progo, Sleman, and City of Yogyakarta) are calculated. Biogas digesters types and options for biogas utilization are evaluated by set of indicators in terms of technical, economic and environmental dimensions. Performance of the four types of digesters (i.e. fixed dome, floating drum, polyethylene tubular and concrete tubular digester) are examined based on the dimensions. For digester assessment, the dimensions are divided into several indicators, such as the lifetime, process efficiency, capital cost, operation and maintenance cost, feed-to-water ratio. The assessment would ensure that installation of biogas have optimum technical performance, attractive investment for the owner, and does not exploit too much natural resources. Equal weighted sum method is used to compare the digesters performance. The second assessment is to evaluate options for off-grid electricity use and cooking based on several indicators which are levelized cost of energy (LCOE), Net Present Value (NPV), Internal Rate of Return (IRR), Benefit-to-Cost Ratio (BCR), Payback period and emissions saving. The production of biofertilizer, which is not part of the current system, is taken into account for additional income for biodigester’s user. The study estimates 1,211.35 TJ/year of biogas energy can be produced from livestock manure or equals to 44.72% of the total energy consumption in the household sector in Yogyakarta province in 2013. Gunung Kidul Regency has the most potential biogas from livestock, followed by Kulon Progo, Sleman, Bantul, then City of Yogyakarta. Utilization of biogas for household cooking could reduce greenhouse gas emissions in the province up to 1,260.66 MtCO2e per year while biogas for electricity reduce 1,562.144 3   MtCO2e annually. The fixed dome digester obtains the highest score in the most of indicators assessed. For biogas utilization, biogas for cooking shows better performance in economic and environmental aspects. Biogas for cooking requires lower capital cost (US$ 850 less) and get higher NPV (US$ 2,000 more) than biogas for electricity. Yet, biogas for electricity save 301.48 MtCO2e more GHG emission than biogas for cooking. From digester and biogas utilization assessments, household biogas in Yogyakarta has been used the sustainable option for digester, which is fixed dome digester, and biogas utilization, which is biogas for cooking. Furthermore, sensitivity analysis is done to know parameters that affect NPV for biogas for cooking and biogas for electricity. Biogas yields, fertilizer price, and LPG price are shown as the top three parameters that affect NPV for biogas for cooking utilization. While for biogas for electricity, the affecting parameter are electricity price, biogas yields, fertilizer price, and generator efficiency. From the sensitivity analysis, several recommendations were developed to maximize the current project. The recommendations are improvement of biogas stove efficiency, recommendation for biogas installation system, creating market demand for biogas by diminishing LPG subsidy, suggestion for progress monitoring and institutional recommendation for the program. Ministry of Energy and Mineral Resource done several monitoring to check whether the digester is still operating. However, there is no follow-up action for digester that is not operating anymore. On the other hand, Yayasan Rumah Energi (YRE), the main provider of biogas installation and service in Yogyakarta Province, conduct annual user survey. This survey focuses on satisfaction level of digester’s user after installation. Investigation regarding the impact of biogas project, such as energy shift from LPG to biogas and digestate utilization, is missing. Besides biogas for cooking, there are opportunity to develop biogas for electricity since several regencies in Yogyakarta does not have 100% electrification ratio, such as Gunung Kidul (82%) and City of Yogyakarta (69%). Due to available biogas potential, development of biogas for electricity in Gunung Kidul is more promising than in City of Yogyakarta. Additionally, research of biogas in Indonesia should be integrated with industries and private sector. For instance, by mass production of low cost generator which had been developed by Indonesian Institute for Sciences (LIPI) and by developing mini grid installation for biogas.
38

Limiting microplastic pollution from municipal wastewater treatment : A circular economic approach / Begränsning av mikroplastföroreningar från kommunal avloppsrening : En cirkulär ekonomisk strategi

van Osch, Jordy January 2020 (has links)
The increasing amount of microplastics found in the environment have underscored the urgency to identify, develop and deploy scenarios in which municipal wastewater treatment plants (MWWTPs) limit the release of urban microplastics into the environment. Simultaneously, the global trend towards a circular economy has defined the conditions for these scenarios in relation to the water-energy- nutrient nexus. This study has created a novel framework between studies into treatment technologies for microplastics removal in wastewater streams and circular economic objectives from policymakers with regard to the water-energy-nutrient nexus. The results of this study build on the existing evidence that MWWTPs release significant amounts of microplastics to both terrestrial and aquatic environments. This study has demonstrated how Multi-criteria Analysis (MCA) can be applied to analyse wastewater treatment scenarios for their ability to limit microplastic pollution from MWWTPs, whilst taking the water-energy- nutrient nexus into account. The MCA has identified MBR inci-eco as the best performing circular economic scenario for limiting microplastic pollution from MWWTPs in to be constructed plants. This scenario includes a Membrane Bioreactor (MBR) with Anaerobic Digestion, energy recovery through incineration and Phosphorus recovery through Ecophos. If already existing MWWTPs aim to upgrade their facility to limit microplastic pollution, CASPACUF with Pyreg as an energy-nutrient recovery is seen as the best performing scenario. The powder activated carbon with ultra filtration (PAC-UF) system would then be installed as an additional polishing step to an existing conventional activated sludge (CAS) system, significantly reducing upfront investment costs. Academia can build upon these results to initiate additional research into novel microplastic filtration specific technologies, business model innovation for wastewater treatment and microplastic pollution prevention at the source and in stormwaters. National and international policymakers should ban the distribution and sale of biosolids for direct land application to limit the pollution of microplastics from bio-solids. Furthermore, efforts should be put in place to limit microplastic pollution at the source by stimulating policies for a ban on the use of microbeads, limit tyre wear and improving design for e.q. washing machines. / Den ökande mängden mikroplast som finns i miljön har understrukit brådskan i att identifiera, utveckla och tillämpa strategier där kommunala avloppsreningsverk (MWWTP) begränsar utsläpp av urbana mikroplaster. Samtidigt har den globala trenden mot en cirkulär ekonomi definierat villkoren för dessa scenarier i förhållande till vatten-energi-näring-näxan. Denna studie har tagit fram ett nytt ramverk mellan studier om reningsteknologier för avlägsnande av mikroplast i avloppsvattenströmmar och cirkulära ekonomiska mål från beslutsfattare med avseende på water-energy-nutrient nexus. Resultaten av denna studie bygger på befintliga bevis på att kommunala avloppsreningsverk släpper ut betydande mängder mikroplast i både mark- och vattenmiljöer. Denna studie har visat hur Multi-Criteria Analysis (MCA) kan användas för att analysera avloppsreningsscenarier utifrån deras förmåga att begränsa mikroplastföroreningar från reningsverk, samtidigt som man tar hänsyn till vatten-energi-näring-näxan. MCA har identifierat MBR-inci-eco som det bäst presterande cirkulära ekonomiska scenariot för att begränsa mikroplastföroreningar från nya verk. Detta scenario inkluderar en Membrane Bioreactor (MBR) med anaerobisk nebrytning, energiåtervinning genom förbränning och fosforåtervinning genom Ecophos. Om redan befintliga verk ska uppgradera sin anläggning för att begränsa mikroplastföroreningar, ses CASPACUF med Pyreg som energi-näringsåtervinning som det bästa scenariot. Det pulveraktiverade kolet med ultrafiltreringssystemet (PAC-UF) skulle sedan installeras som ett ytterligare poleringssteg till ett befintligt konventionellt system för aktiverat slam (CAS), vilket avsevärt minskar investeringskostnaderna. Framtida forskning kan använda dessa resultat för att undersöka nya mikroplastfiltreringsspecifika tekniker, affärsmodellinnovation för avloppsrening och förebyggande av mikroplastförorening vid källan och i stormvatten. Nationella och internationella beslutsfattare bör förbjuda distribution och försäljning av biosolids för direkt markanvändning för att begränsa mikroplastföroreningar från biosolids. Vidare bör åtgärder vidtas för att begränsa mikroplastföroreningar vid källan genom att stimulera policyer för ett förbud mot användning av mikrokulor, begränsa däckslitage och förbättra designen för e.q. tvättmaskiner.
39

Prioritising biochar application to arable land in Sweden : A spatial multi-criteria analysis / Prioritering av biokolsapplikationer på åkermark i Sverige : En rumslig multikriterieanalys

Osslund, Fabian January 2020 (has links)
Biochar, the solid product of thermal conversion of biomass with little or no available air, is acknowledged as a carbon dioxide removal technique and soil enhancer among other applications. Its potential soil enhancing properties consists of increased water and nutrient holding capacities, liming effects and sorption of pollutants. However, not all soils benefit equally from biochar amendments. The thesis aims to investigate the suitability of biochar applications to agricultural soils in Sweden and communicate the results visually with a biochar indication map, illustrating where biochar could serve the highest benefits as a soil improver. A literature review was carried out to analyse the soil enhancing opportunities of biochar applications, which determined that the criteria soil texture, nitrogen leaching, ground moisture, soil pH and soil organic matter (SOM) were suitable for the analysis in a Swedish context. Then, a multi-criteria analysis was conducted in ArcGIS, based on spatial data of these criteria. Each arable land block was assigned a biochar class, varying from high indication to no indication. Arable land was considered highly recommended for biochar applications if the soil texture was sandy and at least one of the soil criteria was beyond a limiting agronomic threshold. At the national level, high indication for biochar application occupied 24.2% (528 thousand ha) of the arable land in Sweden, while the remaining land had either medium indication (13%), low indication (3.5%) or no indication (59.3%). Despite spatial variations, all Swedish counties (with data coverage above 84%) had at least 2% of high indication arable land. In particular, 66.1% of Halland’s arable land showed high indication. In turn, Skåne had the largest area (148 thousand ha, 35.7%) with high indication for biochar applications. The corresponding biochar volume potential, at the national level, suggested that between 0.5 and 26.4 million tonnes biochar can be applied to arable land with high indication for biochar applications, given application rates between 1 and 50 tonnes/ha over a 20 year timeframe. This means that arable land in Sweden can accommodate for a future production of 500 000 tonnes per year, which was suggested as an upper limit in an inquiry from the Swedish government, if application rates remain below 20 tonnes/ha. The multi-criteria analysis performed includes several subjective choices and uncertain parameters (criteria combination, data accuracy, agronomic thresholds, and classification scheme). Therefore, the biochar indication maps cannot yet be used for farm- or field-level recommendations for biochar applications. Nonetheless, despite uncertainties, the national- and county- level indication maps may still provide interesting order of magnitude. More field experiments are needed in Sweden as well as a more detailed analysis. To be able to make more precise recommendations, the present analysis can be refined by connecting all criteria to physical agricultural mechanisms and to the properties of biochar, and by using spatial data with higher resolution or even field-level data. This said, models need to be validated with experimental data, which is to date, non- existent: controlled biochar field experiments are therefore needed in Sweden. / Biokol, en solid produkt från termisk omvandling av biomassa med begränsat syre tillgängligt, är identifierad som en möjlig teknik för att minska halten av koldioxid i atmosfären och som jordförbättrare bland andra applikationer. Dess potentiella jordförbättrande egenskaper består av vattenhållning, näringsbindning, balansering av pH-värdet och minskad biotillgänglighet av föroreningar. Däremot så drar inte alla jordar samma nytta av biokolapplikationer. Arbetet syftar till att undersöka lämpligheten av biokolapplikationer på jordbruksmark i Sverige och kommunicera resultaten visuellt med en indikationskarta. En litteraturstudie genomfördes för att analysera jordförbättringsmöjligheterna till följd av biokolsapplikationer. Det fastställdes att kriterierna jordtyp, kväveläckage, markfuktighet, pH och organiskt material var lämpliga för analys i svensk kontext. En multikriterieanalys utfördes i ArcGIS, baserat på rumsliga data för dessa kriterier. Vardera jordbruksblock tilldelades en biokolklass, som varierade mellan hög indikation och ingen indikation. Jordbruksmark ansågs högt rekommenderad för biokolapplikationer om jordtypen var av sandig karaktär och minst ett av kriterierna översteg ett begränsande tröskelvärde. På nationell nivå ockuperade hög indikation för biokolapplikationer 24.2% (528 tusen hektar) av Sveriges jordbruksmark, medan den återstående marken hade antingen måttlig indikation (13%), låg indikation (3.5%) eller ingen indikation (59.3%). Trots rumsliga variationer, hade samtliga svenska län (med datatillgänglighet över 84%) minst 2% åkermark med hög indikation. I synnerhet, 66.1% av Hallands åkermark visade hög indikation. Vidare, Skåne hade den största arealen (148 tusen hektar, 35.7%) med hög indikation för biokolapplikationer. Den motsvarande potentialen för biokol, på nationell nivå, antyder att mellan 0.5 och 26.4 miljoner ton biokol kan appliceras på jordbruksmark med hög indikation för biokolapplikationer, givet appliceringsgrader mellan 1 och 50 ton/hektar över en 20-årsperiod. Detta innebär att svensk jordbruksmark kan rymma en framtida produktion på 500 000 ton per år, förslaget av en statlig utredning, ifall appliceringsgraden förblir under 20 ton/ha. Den utförda multikriterieanalysen inkluderar flertalet subjektiva val och osäkerheter (kriteriakombination, datans noggranhet, tröskelvärden, och klassificeringsmetod). Därmed kan indikationskartorna för biokol ännu inte användas för rekommendationer på jordbruksblocknivå. Resultaten kan emellertid, trots osäkerheter, antyda intressanta storleksordningar på nationell- och länsnivå. Fler svenska fältexperiment samt en mer detaljerad analys behövs. För att kunna ge mer exakta rekommendationer, kan den nuvarande analysen utvecklas genom att koppla samtliga kriterier till fysiska jordbruksmekanismer och biokolsegenskaper och genom att tillämpa rumsliga data av högre upplösning eller till och med fältnivådata. Modeller måste valideras med experimentella data, som hittills är obefintlig: kontrollerade fältförsök med biokol behövs därmed i Sverige.
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Assessment and relative sustainability of common types of roadside noise barriers

Oltean-Dumbrava, Crina, Miah, Abdul H.S. 18 June 2016 (has links)
Yes / There is increasing legislative and public pressure for the design and build of road infrastructure schemes to achieve better sustainability performance. Roadside noise barriers (RNBs) form a major part of the growing road infrastructure system in mitigating undesirable road noise to impacted communities. However, the relative sustainability of common RNBs is little understood in the research and industry literature. This makes it difficult for stakeholders to make informed decisions with regards to the sustainable design and procurement of RNBs. This paper presents nowel research carried out to assess and rank the relative sustainability of 13 RNB types using three multi criteria analysis (MCA) techniques, i.e. Simple Additive Weighting (SAW), Preference Ranking Organisation MeTHod for Enrichment Evaluations (PROMETHEE), and Elimination et Choice Translating Reality (ELECTRE III). The paper concludes that the presented sustainability rankings of the main RNB types from least sustainable to most sustainable will support the relevant stakeholders, involved in the planning, design, and procurement stages, to evaluate the sustainability of RNB options as either part of a large highways scheme or standalone project. The presented results will save significant analysis time and costs in cases whereby it is unfeasible to conduct MCAs. The presented sustainability asssessment methodology may also provide the basis for an industry sustainability certification sceheme and in turn support advancing the sustainability transport agenda. / FP7 Quiesst research grant funded by the EU.

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