• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 302
  • 39
  • 1
  • 1
  • Tagged with
  • 343
  • 125
  • 67
  • 56
  • 56
  • 45
  • 34
  • 32
  • 29
  • 28
  • 26
  • 24
  • 24
  • 23
  • 23
  • 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.
331

Utveckling av multifunktionell cykelvagn : En studie om ökad lastförmåga i vardagen / Development of a multifunctional bicycle carriage : A studie for increased load capacity in everyday life

Jonasson, Rasmus January 2021 (has links)
Denna rapport behandlar ett projekt för examen inom programmet Högskoleingenjör inom innovationsteknik och design. Projektet genomfördes tillsammans med företaget Atran Velo med målet att utveckla en cykel-/dragvagn som ska integreras med företagets AVS-system. Projektet genomfördes under våren 2021 vid Karlstads universitet och omfattar 22,5 hp. Projektets syfte är att ta fram en vagn som ökar lastförmågan hos en standardcykel. Detta möjliggör att människor kan bruka sin cykel vid flera tillfällen, vilket bidrar till flera positiva aspekter. Genom att transportera sig med cykel i stället för bilen bidrar det till minskade utsläpp. Detta har en positiv påverkan på miljön och klimatet. Det ökar även den fysiska aktiviteten hos människan, vilket bidrar till att individens välmående ökar. Projektet har utgått från produktutvecklingsprocessen med faserna: projektplanering, förstudie, produktspecifikation, konceptgenerering, konceptval, konstruktion, slutprocess och rapportskrivning. I faserna har olika beprövade metoder används.  Projektet resulterade i ett konceptförslag på en vagn och koppling som företaget ska arbeta vidare med efter detta projekt. Vagnen fungerar som både en cykel- och dragvagn som enkelt går att koppla på och av cykeln med en AVS-adapter. Till exempel för att cykla förbi affären och använda vagnen för mathandling. Vagnen har två lastytor som har integrerade AVS-bryggor vilket gör vagnen till en AVS-bärare, med detta menas att vagnen kan användas med företagets olika tillbehör. Vagnen går även att vika ihop för platsbesparing i hemmet för att öka kundvärdet. Vagnen är tillverkad av aluminium för att minimera vikten på produkten och motstå korrosion. / This report deals with a project for a Bachelor of Science in innovation technology and design engineering degree at Karlstad University. The project was conducted on behalf of the company Atran velo. The goal of this project is to develop a bicycle/tractor that is integrated with the company´s AVS-system. The project was carried out during the spring 2021 and comprises 22,5 hp.  The purpose of this project is to develop a trolly that can increase the load capacity when using a standard bicycle. This allows people to use their bicycle on several occasions which contributes to many positive aspects. By taking the bicycle instead of the car it contributes to reduced emission, which has a positive effect on the environment. It can also increase the physical activity of people which contributes to the individual’s health.  The project has been based on the product development process with the phases project planning, pilot study, product specification, concept selection, design, final process, and report writing. In these phases various proven methods have been used.  The result of this project is a concept of a trolley with coupling. The trolley can be used both as a bicycle cart and carriage. It can easily be connected and disconnected from the bicycle, when for example doing grocery shopping. The trolley has two loading surfaces, and both are integrated with AVS - bridges which makes it work like an AVS-carrier. It can also be folded for space saving witch increase customer value. Most of the trolley is made of aluminum which minimize the weight and is corrosion resistance.
332

Jämförelse av värmekällor : Byte av värmekälla i ett småhus ur ett energi-, ekonomi- och klimatperspektiv

Goblirsch, Amanda, Izat, Banaz, Österblad Rintanen, Melinda January 2021 (has links)
Purpose: The aim of this study is to present the economic, environmental impact, and energy saving benefits of replacing an electric boiler to a bedrock heat pump or district heating. Furthermore, the impact of additional insulation will also be presented. Method: The technical, environmental, and economical aspects of the various heat sources in this study are gathered through websites and reports from agencies, industry organisations and corporations. A case study on a family house built in 1971, heated with a combination of electric boiler and air-to-air heat pump has been made. The study investigates the impact of replacing the existing heat sources with newer and better alternatives along with additional insulation. Results: The results present the energy demand for active heating, economic analysis, environmental impact, and the impact of additional insulation. Moreover, a comparison between the heat sources and the additional insulation is presented to show the difference between them. The case study objects demand for active heating includes passive heating, heat losses through the building envelope, heat losses due to ventilation. With all these factors combined, the family house has an annual active heating demand of 11 700 kWh. The energy consumption of the electric boiler combined with air-to-air heat pump (COP 4) have an annual consumption of 7 500 kWh. The required energy from the district heating goes up to 11 700 kWh and the bedrock heat pump (COP 3) have the lowest energy consumption of 3 900 kWh. However, the amount of electricity needed is 400 kWh for district heating compared to the other alternatives that require 7 500 kWh and 3 900 kWh. For the economic aspects, the installation and operating costs for the electric boiler combined with the air-to-air heat pump, district heating and the bedrock heat pump are concluded. This shows that, on one hand the bedrock heat pump is the most expensive heat source to install but on the other hand, the cheapest to operate. Furthermore, this study compares the emissions of carbon dioxide equivalents from the production of district heating and electric energy. Due to the clean electric energy in Sweden, district heating has the highest negative impact on the greenhouse effect as it uses energy resources that have high emission of carbon dioxide equivalents. The environmental impact of the electric boiler, air-to-air heat pump and the bedrock heat pump vary depending on the energy source used to generate electricity and can in the worst case be higher than for district heating. New values with the additional insulation suggest that the improved building envelope will have a positive impact on the operation costs, energy saving and emissions. As an example, the demand for active heating can be reduced with up to 30%. Conclusions: The conclusion is that the comparison of heat sources contains many uncertain variables. Consequently, the result of this study does most likely not apply directly to other study objects. The results may vary if, for example, the geographical location or electricity agreement is changed.
333

A Competitive Environment? : Articles 101 and 102 TFEU and the European Green Deal

Lundgren, Lars January 2021 (has links)
Europe is facing a climate and environmental crisis. To respond to this, the European Commission has launched several programmes, which aim to increase sustainability and environmental protection. This aim has been condensed into the policy document that is the European Green Deal. The European Green Deal sets out the aim of making the Union’s economy climate neutral, while improving environmental protection and protecting biodiversity. To this end, several different sectors of the economy need to be overhauled.  In EU Law, a key policy area is to protect free competition. Article 101 TFEU sets out that agreements between undertakings which have as their object or effect the prevention, restriction or distortion of competition are prohibited. Similarly, Article 102 TFEU prohibits abuse by an undertaking of a dominant position.  This thesis explores what happens when competition law thus intersects with the environmental policy of the Union. The thesis identifies two main situations  of interaction. Undertakings can invoke environmental protection to justify a restriction of competition. The Union may also rely on its antitrust provisions to enforce sustainability by holding unsustainable practices as restrictive agreements or abuses of dominant behaviour, respectively, and thus prohibited by the antitrust provisions.  Generally, the thesis concludes that there is not enough information on how the Commission and the CJEU will approach arguments relating to sustainability in its antitrust assessment. The Commission’s consumer welfare standard appears to limit environmental integration to points where a certain factor results affects the environment or sustainability on the one hand, and consumer welfare on the other. The lack of information, moreover, is in itself an issue as undertakings may abstain from environmental action if they believe they will come under scrutiny due to violations of the antitrust provisions. Therefore, a key conclusion in the thesis is that the Commission and the CJEU should set out clear guidelines for environmental action by undertakings, in relation to the antitrust provisions. Similarly, the Commission appears to be cautious to use antitrust as a tool against unsustainable practices. The Commission has, however, recently decided to open an investigation into agreements which limit sustainability, which shows that the picture may be changing.
334

Adapting to Extreme Weather Events : - Addressing Flood Risks Through Planning and Policy in Namibia

Licke, Tim January 2023 (has links)
This master thesis investigates planning initiatives to address extreme weather events' impacts, specifically focusing on floods in Namibia. The study highlights the significance of such events in the context of global climate change, emphasising their adverse effects on livelihoods, particularly in rural communities and informal settlements. The research aims to evaluate existing strategic plans and policies in Namibia concerning extreme weather events and to examine the extent to which such events are considered when planning initiatives are implemented. Based on the theoretical framework of implementation theory, the study adopts a mixed-method research approach. Document analysis is employed to examine policies and plans related to planning in Namibia, while semi-structured interviews with key informants provide insights into the stakeholders' perspectives. A comprehensive understanding of the subject is achieved by comparing and validating findings from both methods. The results of the study reveal several approaches in current strategic plans and policies regarding the consideration of floods in Namibia. While several documents acknowledge the threat of floods and outline responsibilities and measures, there is a lack of comprehensive and coordinated approaches. The study highlights the need for a more integrated approach and increased alignment among different levels of planning documents. Furthermore, the research shows that the implementation of planning initiatives in Namibia is a centralised process overseen by the Ministry of Urban and Regional Development, with a limited focus on flooding beyond urban areas. The study identifies key challenges in implementing climate change adaptation strategies and projects in Namibia, including limited communication and coordination between actors, difficulties in accessing planning laws, plans and policies, and the centralisation of planning at the national level. However, opportunities for improvement are also recognised, such as enhanced local autonomy in planning processes and the integration of local and indigenous knowledge. Overall, the findings underscore the importance of addressing the impact of extreme weather events, particularly floods, through comprehensive and coordinated planning initiatives in Namibia. The study provides valuable insights for policymakers and planners in developing effective strategies to mitigate and adapt to the effects of climate change in the country.
335

Evaluation of Crop Water Use and Rice Yield Using Remote Sensing and AquaCrop Model for Three Irrigation Schemes in Sri Lanka

Widengren, Veronika January 2022 (has links)
With a changing climate and an increased competition over water resources for agricultural irrigation, the need to improve crop water productivity using time and cost-efficient methodologies have become critically important. The Malwathu Oya river basin in Sri Lanka is struggling with water scarcity, which threatens food security and the income of farmers. In this study, freely available remote sensed land- and water productivity data from FAO’s WaPOR database was evaluated. The evaluation consisted of a comparison of the WaPOR data and primary collected field data using the crop water model, AquaCrop, for three irrigation schemes in the Malwathu Oya river basin. Additionally, the spatio-temporal variability in crop water use within and across these three irrigation schemes was assessed using indicators derived from the WaPOR portal. The evaluation was conducted for the main cultivation season, called Maha, between 2010 and 2021.  The WaPOR and AquaCrop actual evapotranspiration (ETa) values were found to be in relatively good agreement (312–537 and 400–465 mm respectively). WaPOR yield values (2.5–2.9 ton/ha) were however lower compared to the AquaCrop simulated yield values and historical yield data (4.6–5.7 and 4.4–5.6 ton/ha respectively). Difference in calculation methodology, possible sources of error in WaPOR conversion calculations and limitations in accuracy caused by cloud coverage when collecting satellite data could be explanations for this. Prior knowledge and accurate allocation of the crop type and parameters used in conversion calculations in WaPOR is therefore of significant influence. From the spatio-temporal variation assessment with WaPOR indicators, a fair uniformity of the water distribution within the irrigation schemes was shown (CV 11–19 %). The beneficial water use (BWU) in the irrigation schemes showed lower values (50–90 % allocated to T) for years when the available water amount was higher, which could be explained by the higher rate of water lost through soil evaporation. Crop water productivity (CWP) values showed higher values (about 0.70 kgDM/m3) when the available water amount was higher, indicating that yield production is sensitive to water-scarce environments. Applying a yield boundary function, representing the best attainable yield in relation to water resource, showed that there is potential to achieve the same yield with less amount of water. There are thus possibilities for improved water productivity in the three irrigation schemes investigated. For future research it is recommended to perform a sensitivity analysis for WaPOR and ground truth with yield data to obtain a better understanding of potential limitations. To obtain more precise site descriptions it is also recommended to ground truth AquaCrop with yield and soil data.
336

Gymnasiefysikens meteorologiinnehåll : En metodkombinationsstudie om hur klimat och väder implementerats i fysikundervisningen / The meteorology content of physics in upper secondary school : A mixed-methods research study about the implementation of climate and weather in physics education

Borgemo, Joakim, Roth, Richard January 2018 (has links)
Studien undersökte implementeringen och undervisningen av klimat och väder som år 2011 lades till under Fysik 1 i den svenska gymnasieskolan. Undersökningen använde sig av metodkombination som omfattade lärarintervjuer kompletterade med intervju av ett undervisningsråd på Skolverket och med textanalys av kursböcker. Lärarna upplevde en del problem kopplat till vad det nya ämnesområdet skulle innehålla. Oklarheten kring vad området skulle innehålla märktes också i kursböckernas framställning. Intervjupersonerna var överens om att viktiga aspekter inom ämnesområdet var växthuseffekten och global uppvärmning. Växthuseffekten och global uppvärmning hade även en framträdande roll i kursböckernas framställning. Från lärarintervjuerna framkom att lärarna gärna inkluderade Samhällsfrågor med Naturvetenskapligt Innehåll (SNI) i sin undervisning, men i bedömningen av elevernas lärande var det fysikalisk begreppsförståelse som accentuerades. Ämnesöverskridande samarbeten beskrevs av lärarna som önskvärt och förekom ofta. / This study examined the implementation and teaching of climate and weather which was added in the year 2011 under Physics 1 in the Swedish upper secondary school. The study performed a mixed-methods approach consisting of teacher interviews supplemented with an interview with an official at the Swedish National Agency for Education and with text analysis of course books. The teacher’s experienced some problems related to what the new subject area would contain. The uncertainty about what the area would contain was also seen in the course books. The interviewees’ opinion that the important issues in the subject area were the greenhouse effect and global warming were shared among the teachers. The greenhouse effect and global warming also had prominent roles in the course books. From the interviews it was found that teachers were positive to include Socio-Scientific Issues (SSI) into their teaching, but when assessing students learning the concepts of physics were emphasized. Cross-disciplinary cooperation was described by the teachers as desirable and often occurring.
337

Managing Climate Overshoot Risk with Reinforcement Learning : Carbon Dioxide Removal, Tipping Points and Risk-constrained RL / Hantering av risk vid överskjutning av klimatmål med förstärkande inlärning : Koldioxidinfångning, tröskelpunkter och riskbegränsad förstärkande inlärning

Kerakos, Emil January 2024 (has links)
In order to study how to reach different climate targets, scientists and policymakers rely on results from computer models known as Integrated Assessment Models (IAMs). These models are used to quantitatively study different ways of achieving warming targets such as the Paris goal of limiting warming to 1.5-2.0 °C, deriving climate mitigation pathways that are optimal in some sense. However, when applied to the Paris goal many IAMs derive pathways that overshoot the temperature target: global temperature temporarily exceeds the warming target for a period of time, before decreasing and stabilizing at the target. Although little is known with certainty about the impacts of overshooting, recent studies indicate that there may be major risks entailed. This thesis explores two different ways of including overshoot risk in a simple IAM by introducing stochastic elements to it. Then, algorithms from Reinforcement Learning (RL) are applied to the model in order to find pathways that take overshoot risk into consideration. In one experiment we apply standard risk-neutral RL to the DICE model extended with a probabilistic damage function and carbon dioxide removal technologies. In the other experiment, the model is further augmented with a probabilistic tipping element model. Using risk-constrained RL we then train an algorithm to optimally control this model, whilst controlling the conditional-value-at-risk of triggering tipping elements below a user-specified threshold. Although some instability and convergence issues are present during training, in both experiments the agents are able to achieve policies that outperform a simple baseline. Furthermore, the risk-constrained agent is also able to (approximately) control the tipping risk metric below a desired threshold in the second experiment. The final policies are analysed for domain insights, indicating that carbon removal via temporal carbon storage solutions could be a sizeable contributor to negative emissions on a time-horizon relevant for overshooting. In the end, recommended next steps for future work are discussed. / För att studera hur globala klimatmål kan nås använder forskare och beslutsfattare resultat från integrerade bedömningsmodeller (IAM:er). Dessa modeller används för att kvantitativt förstå olika vägar till temperaturmål, så som Parisavtalets mål om att begränsa den globala uppvärmningen till 1.5-2.0 °C. Resultaten från dessa modeller är så kallade ”mitigation pathways” som är optimala utifrån något uppsatt kriterium. När sådana modellkörningar görs med Parismålet erhålls dock ofta optimala pathways som överskjuter temperaturmålet tillfälligt: den globala temperaturen överstiger målet i en period innan den sjunker och till slut stabiliseras vid det satta målet. Kunskapen om vilken påverkan en överskjutning har är idag begränsad, men flertalet nyligen gjorda studier indikerar att stora risker potentiellt kan medföras. I denna uppsats utforskas två olika sätt att inkludera överskjutningsrisk i en enkel IAM genom användandet av stokastiska element. Därefter används Förstärkande Inlärning på modellen för att erhålla modellösningar som tar hänsyn till överkjutningsrisk. I ett av experimenten utökas IAM:en med en stokastisk skadefunktion och tekniker för koldioxidinfångning varpå vanlig Förstärkande Inlärning appliceras. I det andra experimentet utökas modellen ytterligare med en stokastisk modell för tröskelpunkter. Med hjälp av risk-begränsad Förstärkande Inlärning tränas därefter en modell för att optimalt kontrollera denna IAM samtidigt som risken att utlösa tröskelpunkter kontrolleras till en nivå satt av användaren. Även om en viss grad av instabilitet och problem med konvergens observeras under inlärningsprocessen så lyckas agenterna i båda experimenten hitta beslutsregler som överträffar en enkel baslinje. Vidare lyckas beslutsregeln som erhålls i det andra experimentet, med den risk-begränsade inlärningen, approximativt kontrollera risken att utlösa tröskelpunkter till det specificerade värdet. Efter träning analyseras de bästa beslutsreglerna i syfte att finna domänmässiga insikter, varav en av dessa insikter är att temporära kollager kan ge betydande bidrag för koldioxidinfångning i en tidshorisont relevant vid överskjutning. Slutligen diskuteras möjliga nästa steg för framtida arbeten inom området.
338

Naturligt farligt : Hur visualiseringar av klimatförändringar är laddade med tecken och känslor

Jägerskog, Mattias January 2010 (has links)
<p>The purpose of this thesis was to examine the relationship between feelings and visualizations of climate change. A case study was done on visualizations of climate change from a web page concerning climate change published by the Swedish newspaper <em>Expressen </em>and from the American photographer Gary Braasch’s web page “World view of global warming”. The thesis is based on the article ”Emotional anchoring and objectification in the media reporting on climate change” by Birgitta Höijer. I have been aiming to understand the feelings of fear, hope, guilt, compassion and nostalgia through semiotic theories of icon, index and symbol.</p><p>Previous research has proven the difficulties in bringing the issue of climate change up on the public agenda – which is connected to the difficulties of visualizing climate change. The nature of climate change being slow and hard to spot on an individual level has been highlighted as a cause of both of these difficulties. Pictures and photos have in this thesis been seen as the “interface” between science and the public – and hence <em>decoders</em> of the science of climate change. Höijer’s article about feelings has been used to understand this process of decoding.</p><p>The results show that the analyzed material could be linked to and described by the semiotic theories of icon, index and symbol. The emotional anchoring found in the material and the semiotic application have been shown to work complementarily with each other, leading to a broader understanding of the material’s relationship to social cognitions. The results further demonstrated that context is essential in some of the analyzed visualizations of climate change. Generic pictures found in the material could have been regarded as icon, index or symbol of other messages – but is through its contexts anchored with feelings, and becomes visualizations of climate change. The analysis also suggests that if icons of nature could be connected with feelings – so could nature itself. The consequences are speculated to lead to objectification of nature and ecophobia. By objectifying nature and using generic pictures, the material’s relationship to the concepts of “truth” and “myth” is questioned.</p><p>In conclusion, understanding of the analyzed material is advantageously achieved through complementary use of Höijers emotional categories and the semiotic theories of icon, index and symbol.</p>
339

Naturligt farligt : Hur visualiseringar av klimatförändringar är laddade med tecken och känslor

Jägerskog, Mattias January 2010 (has links)
The purpose of this thesis was to examine the relationship between feelings and visualizations of climate change. A case study was done on visualizations of climate change from a web page concerning climate change published by the Swedish newspaper Expressen and from the American photographer Gary Braasch’s web page “World view of global warming”. The thesis is based on the article ”Emotional anchoring and objectification in the media reporting on climate change” by Birgitta Höijer. I have been aiming to understand the feelings of fear, hope, guilt, compassion and nostalgia through semiotic theories of icon, index and symbol. Previous research has proven the difficulties in bringing the issue of climate change up on the public agenda – which is connected to the difficulties of visualizing climate change. The nature of climate change being slow and hard to spot on an individual level has been highlighted as a cause of both of these difficulties. Pictures and photos have in this thesis been seen as the “interface” between science and the public – and hence decoders of the science of climate change. Höijer’s article about feelings has been used to understand this process of decoding. The results show that the analyzed material could be linked to and described by the semiotic theories of icon, index and symbol. The emotional anchoring found in the material and the semiotic application have been shown to work complementarily with each other, leading to a broader understanding of the material’s relationship to social cognitions. The results further demonstrated that context is essential in some of the analyzed visualizations of climate change. Generic pictures found in the material could have been regarded as icon, index or symbol of other messages – but is through its contexts anchored with feelings, and becomes visualizations of climate change. The analysis also suggests that if icons of nature could be connected with feelings – so could nature itself. The consequences are speculated to lead to objectification of nature and ecophobia. By objectifying nature and using generic pictures, the material’s relationship to the concepts of “truth” and “myth” is questioned. In conclusion, understanding of the analyzed material is advantageously achieved through complementary use of Höijers emotional categories and the semiotic theories of icon, index and symbol.
340

Sverige 2112 : Ett narrativ om hur arkitekturen kan utvecklas om världen går igenom stora förändringar på grund av klimatförändringarna. En linjär och vertikal stad. / Sweden 2112 : A narrative of how architecture could be developed if the world is going through major changes due to the climate changes. The wall city.

Eliasson, David January 2012 (has links)
Om världen till följd av klimatförändringarna blir mycket varmare kommer förutsättningarna för hur vi planerar städer, infrastruktur och jordbruk helt att vändas upp och ner. De delar av världen som idag står för världens livsmedelsproduktion kommer vid bara några graders förändring bli obrukbara som betes och odlingsmark. Dessa förändringar kan komma att starta konflikter, och stora flyktingströmmar som tillsammans med förändrade klimatzoner helt kommer att rita om världskartan. i Skandinavien är det då troligt att vi behöver bygga samhällen och städer för miljontals nya immigranter, och detta samtidigt som vi befinner oss mitt i den mest fruktbara jordbruksmarken i världen. Om hundra år måste vi dessutom, oavsett detta, dubbla livsmedelsproduktionen globalt sett. Vårt samhälle blir allt mer rörligt och infrastrukturen utvecklas i allt snabbare takt. Tåget, bilen och flyget har alla förändrat världen och staden, och i framtiden kommer vi kanske förflytta oss med nya typer av till exempel supersnabbtåg. De kommer ge avstånd en allt mindre betydelse. Om vi använder oss av de förutsättningar en sådan ny infrastruktur ger, och bygger både horisontellt och vertikalt uppstår en ny typologi för staden. Stannar man vid detta inser man snart att det är en hissnande tanke, och det är just det som detta examensarbete  undersöker. Ett narrativt projekt som spekulerar i frågan om det här händer, kan då också det här hända? / If the world as a result of the climate changes will be much warmer, the conditions for how we plan cities, infrastructure and agriculture will be completely turned upside down. Parts of the world which today account for the world's food production will at just a few degrees of temperature change become unusable for cultivation. These changes may result in conflicts, and massive refugee flows. Changes of the climate zones will completely redraw the map of the world. In Scandinavia, is it likely that we will need to build societies and cities for millions of new immigrants. At the same moment Scandinavian countries are in the midst of the most fertile farmland in the world. And also, in one hundred years we must, notwithstanding this, double our food production globally. Our society gets more and more mobile and the infrastructure is developing more and more. The train, the car and the airplane as concepts have all changed the world and the cities when they where introduced. The future, might move us towards new types of super-fast speed trains that will give an even smaller importance to distances. And if we use the textures of these new infrastructures, it might lead us to build both horizontally and vertically. Then it appears a new type of typology of cities. If you stay at this thought, you realize that it is completely staggering, and that is exactly what the thesis project investigates. It is a narrative project that speculates on the question; "If this happens, might then also this happen?"

Page generated in 0.0477 seconds