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Life Cycle Assessment of Railway Bridges : Developing a LCA tool for evaluating Railway BridgesGarcía San Martín, Lorea January 2011 (has links)
The global understanding that natural resources and non renewable energy sources are not inexhaustible has been growing lately together with the increase of conscientiousness on the consequences that our demanding way of life has on the environment. Global warming, ozone layer depletion, the greenhouse effect or the acid rain, are some of these consequences, which may reach catastrophic levels if nothing is done to emend the actual situation. Lately, society is beginning to see sustainability not only as a needed requirement but as a distinctive value which has to be pursued by the different areas of society involved and responsible for a sustainable development such as public administration and companies, engineers and researchers. As a fundamental part of society, infrastructures have utmost importance in sustainable development. Even more when it comes to rail transport infrastructure, given the important role of rail transport in the development of a sustainable society. That is why engineers should make an effort to use all the tools available to choose the best structural design, which not only meets structural requirements, but has also a good performance for the environment. To do so, engineers must focus on using renewable sources or energy and materials, increasing the life of the existing infrastructures, making them more durable. When it comes to railway bridges, it is preferable to reuse and adapt existing structures than tear them down to build new ones. In this line, environmental assessment methodologies provide an incredibly valuable tool for help decision-makers and engineers to identify and select the best alternative design regarding environmental issues. Therefore, it is important to count on a common basis and established criteria together with a systematic methodology in order to obtain reliable results to compare alternatives and make the right decisions. However, nowadays, there exists very little guidance to perform this kind of analysis, and an extensive variety of databases and methodologies non standardized, which leads to uncertainties when it comes to evaluate and compare the obtained results. This thesis means to be a good guide for engineers, when performing a Life Cycle Assessment of a railway bridge, and to become a useful tool to compare several alternatives to identify the best option relating the environmental burdens involved. With this purpose, in order to know the state of the art of LCA methodology, it has been studied a wide range of existing literature and previous studies performed to analyze bridges and building materials. Finally, it has been developed an own methodology based on all the research done before, and implemented in an Excel application program based on Visual Basic macros, which means to be easy to use with a simple user interface, and to provide reliable results. The application is useful for assessing, repair or improving existing bridges, where the amounts of materials and energy are known, but can also be helpful in the design phase to compare different alternatives. It also allows using different weighting methodologies according to several reference sources depending on the case of study. The application is tested by carrying out a Life Cycle Assessment of a Spanish railway bridge located in the city center of Vitoria-Gasteiz, evaluating the different structures that conform the bridge system thorough all the stages of its life cycle identifying the most contributive parameters to the environmental impacts. The study was carried out over a 100 year time horizon. In the case of performing the LCA of this particular bridge, the contribution of the whole bridge is taken into consideration. When comparing two different bridges, the application has the option to compare them in the same basis, dividing by length and width of the bridge, which is a helpful tool if both bridges are not the same size. All stages of the life cycle were considered: the material stage, construction, the use and maintenance stage, and the end of life. The material stage includes the raw material extraction, production and distribution. The construction stage accounts the diesel, electricity and water consumption during construction activities. The use and maintenance stage covers the reparation and replacing operations. And the end of life covers several scenarios. In this case of study, in order not to interrupt the rail traffic, the bridge was constructed parallel to its final location, and then moved into the right place with hydraulic jacks. This leads to an important auxiliary structure with its own foundations, which has a significant contribution to the overall environmental impact. The scenario chosen for the end of life was based on similar actuation in other constructions in the proximities of the bridge, as the bridge is already in use. These assumptions were to recycle 70 % of the concrete and 90 % of the steel; all the wood used for formwork was disposed as landfill. The results obtained, weighted according to the US Environmental Protection Agency, shows that the main contributor to the environmental impacts is the material phase, with the 64 % of the total weighted results with concrete and steel production as principal factors, followed by timber production. These processes account great amounts of CO 2emissions, which makes essential to focus on reducing the impact of the material processes by optimizing the processes but mainly by reusing materials from other constructions as much as it may be possible. The maintenance activities have some importance due to the frequency of the track replacement, assumed to be once every 25 years. While construction does not imply great burdens for the environment, the end of life causes the 33 % of the overall bridge impact. This is due to the timber formwork disposal as landfill and to a lesser extent because of the recycling of the steel. The timber disposal increases widely the eutrophication effect, and will be easy to be reused in further constructions. Regarding the different parts of the bridge structure, the auxiliary structure has an important contribution with the 61 % of the overall weighted impact. As it is a concrete bridge, both the substructure and superstructure has similar contribution. The substructure has a slightly higher impact with the 21 % and the superstructure the 15 %. Rail structure and transport have very little contribution.
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Ökade isoleringstjocklekars möjligheter och begränsningar / Possibilities and limitations of increased insulation thicknessesEriksson, Per, Rosenlund, David January 2020 (has links)
Sammanfattning Syfte: Bygg och fastighetssektorn står för en stor andel av de nationella utsläppen av växthusgaser. Studier visar att klimatpåverkan för drift och produktionsfasen är ungefär ekvivalenta. Majoriteten av produktionsfasens klimatpåverkan härstammar från materialen. Samtidigt som det behövs byggas fler bostäder behöver klimatpåverkan för denna sektor minska, för att uppnå bestämda klimatmål. För att klara av dessa utmaningar behöver isoleringsmaterial och deras påverkan belysas. Isoleringsmaterialet i en byggnad har som syfte att bibehålla värmen i inneklimatet genom att isolera mot ytterklimatet. Tjockare isoleringsskikt leder till bättre isoleringsförmåga och därmed lägre behov för uppvärmning. Dock leder ökad isoleringstjocklek till mer materialåtgång som i sin tur innebär ökad klimatpåverkan för väggkonstruktionen i sin helhet. ”Målet med studien är att klargöra hur olika tjocklekar på isoleringsmaterial av mineralull och cellulosa i byggnader påverkar miljön ur ett livscykelperspektiv. Samt att undersöka vilka marknadsandelar de ingående materialen har.” Metod: Studien har en kvantitativ ansats med fallstudie, litteraturstudie samt dokumentanalys som metod för att uppnå målet genom att besvara frågeställningarna. Resultat: Mineralull står för minst 50% av marknaden. De förnyelsebara isoleringsmaterialen har kring 2% av marknaden. Cellulosa är det populäraste isoleringsmaterialet av de förnyelsebara. Studien visar på att byggnaden kan öka isoleringen i väggar över det befintliga med cellulosa 813mm, glasull 268mm och stenull 176mm. Isolering i tak kan ökas med 938 mm cellulosa, 319 mm glasull och 214 mm stenull. Återvinning kan möjliggöra att tilläggsisoleringen kan ökas med 103–140% jämfört med hur isoleringsmaterialen avfallshanteras i dagsläget. Konsekvenser:▪ Mineralull står för en stor andel av marknaden, samtidigt som cellulosa enbart står för någon enstaka procent ▪ Vid bestämmande av isoleringstjocklek ur ett klimatperspektiv, spelar val av isoleringsmaterial och avfallshantering en betydande roll ▪ Hur stor klimatpåverkan ett isoleringsmaterial har begränsar mängden isolering som bör användas i byggnaden ▪ Klimatpåverkan för vald uppvärmningsmetod kommer påverka mängd isolering som bör användas i byggnaden Begränsningar: Denna studie är specifik för denna fallstudie. Resultatet kan ses som en fingervisning kring hur olika tjocklekar av isolering påverkar liknande byggnader. Ingen hänsyn tas till konstruktion och att minskat värmebehov leder till ändrade tekniska lösningar. / Abstract Purpose: The construction and real estate sector are responsible for a large part of the national emissions of greenhouse gases. Study’s shows that construction and the usage phase has more or less the same climate impact. In the construction phase, most of the climate impact comes from the materials. At the same time as there is needs for more residential there is also a need for this sector to reduce its climate footprint to achieve national climate goals. More knowledge about insulation materials is needed to achieve these challenges. The purpose of insulation in buildings is to keep the heat inside and protect against the outdoor climate. Thicker insulation gives a better insulation and therefor lower demand of heating. Thicker insulation leads however to increased material usage and therefor higher environmental impact. “The purpose of this study is to clarify the environmental impact of insulation thicknesses through a lifecycle analysis. Recycling and market shares of insulation materials are analyzed as well.” Method: To reach the goal, the study uses a quantitative approach with case study, literature study and document analysis as methods. Findings: Mineral wool has at least 50% of the insulation market. The renewable materials have around 2% of the market, of these percent cellulose is the dominated insulation material. The study shows that the building in the case study can increase its insulation on the walls with cellulose 813mm, glass wool 268mm, stone wool 176mm. increased roof insulation with cellulose 938mm, glass wool 319mm, stone wool 214mm. Recycling can increase the amount of added insulation by 103-140% compared to landfill and incineration alternative. Implications: ▪ Mineral wool has a significant share of the insulation market, at the same time as cellulose only have a couple percent of the market ▪ When determine insulation thickness from an environmental perspective, the insulation material and the waste treatment methods have a considerable impact. ▪ The environmental impact of an insulation material limits the amount that should be installed in the building. ▪ The environmental impact of heating method will impact the amount of insulation that should be installed in the building Limitations: The study is only applicable for its building. The results can however be used as guidance in insulation thicknesses on similar buildings. This study does not take into consideration how increased wall and roof dimensions effects structural and decreased need on the heating system.
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Optimization of Methane Yield in Solid-State Anaerobic Co-Digestion of Dairy Manure and Corn StoverAjayi-banji, Ademola January 2020 (has links)
Sole dependence on fossil fuel and the concomitant environmental concerns could be minimized through the optimization of green energy generation from the growing volume of onfarm organic wastes. In this mesophilic study, green energy, mainly methane, was optimized through the solid-state anerobic co-digestion (SSAD) of two on-farm organic wastes (dairy manure with corn stover). Factors considered to achieve the improved methane yield under a total solids of 16% were particle size of corn stover (0.18 – 0.42 and 0.42 – 0.84 mm), alkaline pretreatment type (thermo-chemical and wet state), alkaline-pretreatment reagent (NaOH, NH4OH, and Ca(OH)2) used for the corn stover, and the magnetite nanoparticles(20, 50, and 75 mg/L) thereafter added to the treatment with highest methane yield. Kinetic models were used to describe some of the high methane yield as well as the environmental impact investigated with life cycle assessment. Results indicated that corn stover with particle size 0.42 - 0.84 mm blended with dairy manure under a C/N of 24 had the highest methane yield (106 L/ kgVS) under 60 days retention time. After pretreatment of the 0.42 - 0.84 mm corn stover with the three different alkaline reagents, methane yield improved under this wet state pretreatment relative to thermochemical. For instance, calcium pretreated corn stover blended with dairy manure (CaW) had the highest methane yield (176 L / kgVS) under a reduced retention time (79 days), overcame potential volatile fatty acids accumulation and digester upset relative to other pretreated treatments. Furthermore, addition of 20 mg of the nanoparticles to the CaW treatment further enhanced methane yield (191 L / kg VS), minimized digester upset, and reduced retention time to 52 days. Suitable process parameters for methanogenic activities were 0.1 - 0.5 for VFA/Ammonia and VFA/Alkalinity ratios. Free ammonia concentration between 258 – 347 mg/L does not affect methanogenic activities. Environmnetal impact aseessment indicated that pretreatment negatively influenced human health factors and eutrophication potentials though reduced ozone depletion, global warming potential, and smog potentials. The solid-state of dairy manure co-digested with corn stover has the potential to improve green energy generation that could complement fossil fuel and address waste management challenges.
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Aerial photography and environmental impact analysis : the potential contribution of comparative interpretation of multi-temporal aerial photographs to Environmental Impact AnalysisBayne, Sandra Maureen January 1984 (has links)
Bibliography: pages 123-133. / The hypothesis was advanced that comparative interpretation of multi-temporal aerial photographs can be used as a tool in Environmental Impact Analysis (EIA). To test this hypothesis a site, Silwerstroomstrand, approximately 40 kilometres north of Cape Town on the West coast was chosen. An analysis of the site was carried out using aerial photographs taken in 1938, 1960, 1968, 1971, 1977, 1981 and 1983 at scales ranging from 1:7 000 to 1:50 000. Development of the site for recreation began in 1972 and in 1976 for water extraction. Pre-development photographs, 1938, 1960, 1968 and 1971, were stereoscopically compared and the observations were interpreted using a systems approach. From the analysis of the photographs and information on past landuse, the dynamics of the site were described with particular attention to the response of that environment to perturbations such as fire and removal of vegetation. Development actions were analysed to establish any similarity to past perturbations and on the basis of similarities, predictions of probable future responses of the site (and hence impacts) were made. The predicted impacts were compared with: 1. the interpretation of post-development photographs. 2. Impacts identified by a multi-disciplinary panel after a visit to the site. It was found that the major limitation of multi-temporal aerial photographs was the spatial resolution of the early (pre 1970) photographs. However, the capabilities of the tool for quantitative and semi-quantitative data gathering; promoting an understanding of spatial and temporal relationships; monitoring change; communicating information and the fact that it is economical means that it has a positive contribution to make to Environmental Impact Analysis is suggested that the optimal use of the tool of comparative interpretation of multi-temporal aerial photography is to combine it with other tools such as site visits and multi-disciplinary panels.
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Signatures épigénétiques associées à l’état physiologique, nutritionnel et pathologique chez la vache laitière en postpartum. / Epigenetic signatures related to physiological, nutritional and pathologic states in dairy cows in postpartum periodGasselin, Maxime 04 July 2017 (has links)
La santé et la fertilité des vaches laitières sont au cœur des préoccupations de la filière professionnelle dans un objectif d’efficience, de quantité et de qualité de la production de lait. La mise en place d’une lactation performante se superpose aux profonds changements hormonaux et métaboliques de la période postpartum, se traduisant par une balance énergétique négative. Les conséquences en sont souvent une altération de la fertilité et une immunodépression qui accroit la susceptibilité aux pathologies. Dans les élevages, il existe encore une grande variabilité d’état général et de performances chez les vaches laitières malgré la sélection génomique. Il est proposé que des modifications de la méthylation de l’ADN puissent contribuer à cette variabilité phénotypique individuelle. En effet, la méthylation de l’ADN, en tant que processus épigénétique, est impliquée dans la régulation transcriptionnelle des gènes, et présente une certaine plasticité face aux contraintes environnementales. Nous avons fait l’hypothèse que des signatures épigénétiques portées par les cellules du sang, pourraient refléter l’état de santé des vaches et pourraient être modifiées en réponse à différents facteurs intrinsèques (parité, stades physiologiques…) et aux contraintes environnementales. Ces signatures ont été recherchées dans une population de cellules du sang particulière : les monocytes. Ces cellules, accessibles par prélèvements sanguins et purification en présence d’un anticorps spécifique, constituent la première ligne de réponse d’immunité innée face aux infections aigües participant à la dégradation de l’état de santé des vaches en postpartum. Pour tester l’hypothèse de signatures épigénétiques monocytaires, une analyse du méthylome par « Reduced Representation Bisulfite Sequencing », (RRBS) dans diverses situations d’élevage a été réalisée. En utilisant des ADN génomiques de vaches incluses dans plusieurs protocoles, 22 banques ont été construites et séquencées. Leur analyse a été réalisée en utilisant un pipeline d’analyses bioinformatique et biostatistique développé au laboratoire.En moyenne 1 250 000 CpG sont pris en considération et permettent l’identification et la localisation de cytosines différentiellement méthylées (DMC) : i) 27143 DMC en comparant les méthylomes de différents types cellulaires (monocytes versus fibroblastes et PBMC) ii) 4788 DMC en réponse à un challenge nutritionnel basé sur la distribution du complément alimentaire GENIAL®, fabriqué et distribué en élevage par nos partenaires PILARDIERE et XR-Repro. iii) 2615 et 4616 DMC en réponse au challenge infectieux pour le groupe de vaches témoins et le groupe en restriction alimentaire respectivement (protocole coordonné par Christine Leroux et José Pires (RUMINFLAME, INRA, Theix) combinant une restriction alimentaire et un challenge immunitaire, par injection de LipoPolySaccharide). iv) 4420 DMC issues de la comparaison entre méthylomes de vaches à génome constant (issues du transfert nucléaire, clones) et de vaches à génome variable mais de même âge et élevées dans les mêmes conditions que les clones. Pour certaines régions différentiellement méthylées (DMR) ciblant le promoteur de gènes, le statut de méthylation a été confirmé par conversion bisulfite et pyroséquençage. L’expression des gènes associés a été étudiée. Une anti corrélation significative est observée entre méthylation et expression signant la fonctionnalité de ces régions.En comparant les 11 méthylomes monocytaires, il est montré que 21% des CpG sont extrêmement stables et ne présentent qu’une faible variation de méthylation entre échantillons ( 20%). L’ensemble de ces informations peut être pris en considération pour la conception d’un outil d’épigénotypage. A l’avenir, il serait aussi possible d’utiliser cet outil en routine afin d’appréhender les variations du méthylome monocytaire dans différentes conditions d’élevage. / In dairy breeding, the health and fertility of cows are the main concern with the aims to maintain milk quantity and quality and to reduce the interval between calving in a high competitive economical context. Postpartum period is marked by major hormonal and metabolic changes that affect productivity, immune responses and fertility. The consequences of immune response deterioration are an increasing susceptibility to diseases (mastitis, metritis, endometritis…). Genomic selection in livestock improves the performance of the population but does not exclude phenotypic variability at the level of livestock and the individual. It is proposed that DNA methylation could contribute to this individual phenotype variability. Indeed, DNA methylation is an epigenetic process involved in transcriptional regulation of genes displaying certain plasticity in front of environmental constraints.We assumed the epigenetic signatures carried by blood cells, could reflect overall health and could be modified in response to intrinsic factors (parity, stages …) and to environmental changes. These signatures were researched in a particular blood cells subpopulation: the monocytes. These cells, obtained by blood sampling and purification with a specific antibody, are the first line of defense against acute infections participating in health status deterioration of postpartum cows.To test the monocyte epigenetic signatures hypothesis, monocyte methylome were analyzed by « Reduced Representation Bisulfite Sequencing » (RRBS), in various breeding conditions. Using genomic DNA form cows included in several protocols, 22 libraries were constructed and sequenced. Their analyses were accomplished using a « homemade » pipeline which integrates bioinformatics and biostatistics analyses. On average, 1 250 000 CpGs were analyzed in order to identify differentially methylated cytosines (DMCs): i) 27143 DMC by comparison between different cells types (monocytes versus fibroblasts and PBMC) ii) 4788 DMCs in response to nutritional challenge based on the dietary supplement, GENIAL®, produced and distributed in breeding by our partner PILARDIERE and XR-Repro (in collaboration with Marion Boutinaud, INRA, Rennes). iii) 2615 and 4616 DMCs in response to infectious challenge with LipoPolySaccharide injection for control cows group fed normal diet and for dietary restriction cows group, respectively (collaboration with Christine Leroux and José Pires, RUMINFLAME, INRA, Theix; and Gilles Foucras (ENVT, Toulouse)). iv) 4420 DMCs from the comparison between constant genomic cow (Somatic cell nuclear transfer, clones) and variable genomic cows but with the same age and raised in the same conditions than clones.From DMCs, we identified differentially methylated regions (DMRs) defined as region with at least 3 DMCs inside 100 bp. For some DMRs targeting gene promoter, the methylation status was validated by bisulfite conversion and pyrosequencing. Gene associated expression were also investigated. A significant negative correlation has been observed between methylation and expression, highlighting the functional relevance of these DMRs in gene transcription control.By comparing the 11 monocyte methylomes, 21% of CpGs present a remarkable constant methylation level with weak variability between samples (20%).Taking together, these data can provide a list of relevant DMCs for an epigenetic tool conception. In the future, it would be possible to use this tool for a routine analysis in order to grasp monocyte methylome variations in different breeding management.
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Influencer Marketings påverkan på köpbeteende och klädkonsumtion hos Millennials & Generation ZHelles, Lisa, Engström, Julia January 2022 (has links)
Influencer marketing är en effektiv marknadsföringsmetod för att öka köpbeteendet hos konsumenter. Uppsatsens fokus är att undersöka Millenials och Generation Z:s klädkonsumtion av Fast Fashion och hur de påverkas av Influencer marketing samt förhållningssätt till miljöfrågor vid klädköp. En växande klädkonsumtion och klädtillverkning går inte ihop med behovet av att konsumera mindre och engagera sig kring miljöfrågor. En studie har genomförts i form av intervjuer med strategiskt utvalda respondenter inom generationskategorierna Millennials och Generation Z. Resultatet visar att generationerna inte reflekterar över den miljöpåverkan klädindustrin har, samt att kvinnor och yngre personer i större utsträckning än män och äldre personer påverkas av Influencer marketing. Resultatet visar även att Influencer marketing är ett mycket effektivt marknadsföringsverktyg för att öka köpbeteendet hos konsumenter.
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Environmental Impacts of Aquaculture Ponds on Coastal Wetlands in the Yellow River Estuary / 黄河河口における養殖が湿地に及ぼす影響に関する研究Fu, Jing 23 May 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第20595号 / 地環博第166号 / 新制||地環||33(附属図書館) / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 柴田 昌三, 教授 山下 洋, 准教授 深町 加津枝, 教授 横山 壽 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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Beyond the Bag Ban: Voluntary Strategies for Reducing Disposable Bag Use in Athens, OhioDalzell, Jessica L. 20 September 2019 (has links)
No description available.
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Towards democratic decision-making In environmental law: An investigation of the implementation of public Participation and access to administrative justiceMasesa, Raphael Chisubo January 2010 (has links)
Magister Legum - LLM / An environment, which is not dangerous to the health or well-being of
individuals, is every South African's basic Human right.1 In addition.it is every
South African's basic human right to have the environment protected for the ·
"benefit of present and future generations, through reasonable legislative and
other measures".2 These measures must aim at preventing pollution and
ecological degradation. The measures must further advance. conservation,
and guarantee ecologically sustainable development and use of natural .·
resources. 3 Stakeholders, such as, non-governmental, organizations
(henceforth NGOs), and the community as a whole have important roles to
play.4
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Kostnads- och miljöbesparingar : genom omstrukturering av logistikflöde / Cost- and environmental savings : through restructuring of the logistic flowPersson, Elsa, Motéus, Philip January 2023 (has links)
Domestic road transport is currently responsible for a third of Sweden's total greenhouse emissions. At the same time, freight transport is not being used efficiently. Full load carriers enable reduced environmental impact, reduced costs and the release of vehicles on the roads. In order to achieve sustainable supply chains, cooperation between actors is important. In the light of this, this study aims to analyze the restructuring of the logistics flow between three actors and what environmental and economic savings can be achieved. Furthermore the collaboration between the parties has been analyzed. To answer the purpose of the study, the authors conducted semi-structured interviews and collected quantitative data that formed the basis for calculating cost and environmental savings. Conclusions drawn are that the restructuring generates environmental savings of 3 724 kilograms of carbon dioxide emissions and cost savings of SEK 46,000 per month. Finally, it is concluded that restructuring of the logistics flow requires increased accuracy in orders and forecasts as all actors will be drawn closer together and given the opportunity to streamline the joint logistics flow through better communication and geographical proximity. / Inrikes vägtransporter står idag för en tredjedel av Sveriges totala utsläpp av växthusgaser, samtidigt som godstransporter i nuläget inte används effektivt. Fulla lastbärare möjliggör minskad miljöpåverkan, minskade kostnader och minskat antal fordon på vägarna. För att uppnå hållbara logistikflöden är samverkan mellan aktörer en central del. Mot bakgrund till detta syftar denna studie till att analysera en omstrukturering av logistikflödet mellan tre aktörer och vilka miljömässiga och ekonomiska besparingar som kan uppnås. Vidare har även samarbetet mellan aktörerna analyserats. För att besvara studiens syfte har författarna genomfört semistrukturerade intervjuer samt insamlat kvantitativa data, vilket utgjort underlag för beräkning av kostnads- och miljöbesparingar. Slutsatser som dras är att omstruktureringen genererar miljöbesparingar på 3 724 kilogram i koldioxidutsläpp samt kostnadsbesparingar på 46 000 kronor per månad. Slutligen konstateras att en omstrukturering av logistikflödet kräver ökad noggrannhet i beställningar och prognoser då samtliga aktörer kommer att dras närmare varandra. Sålunda skulle aktörerna ges möjlighet att effektivisera det gemensamma logistikflödet genom förbättrad kommunikation och geografisk närhet.
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