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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.
1

A temporal and spatial analysis of China's infrastructure and economic vulnerability to climate change impacts

Hu, Xi January 2017 (has links)
A warmer climate is expected to increase the risks of natural disasters globally. China is one of the hotspots of climate impacts since its infrastructures and industries are often hard hit. Yet little is known about the nature and the extent to which they are affected. This thesis builds novel system-of-systems risk assessment methodologies and data for China, representing infrastructures (energy, transport, waste, water and digital communications) as interdependent networks that support spatially distributed users of infrastructure services. A unique national-scale geo-spatial network database containing 64,834 existing infrastructure assets is assembled. For the first time, flood and drought exposure maps of China's key infrastructures are created, highlighting the locations of key urban areas to understand how its infrastructures and population could be exposed to climate impacts. To deepen the understanding of how climate change will affect the Chinese infrastructure system and hence its economy, economic impact modelling is applied. The research combines a detailed firm-level econometric analysis of 162,830 companies with a macroeconomic input-output model to estimate flood impacts on China's manufacturing sector over the period 2003 - 2010. It is estimated that flooding on average reduces firm output by 3.18% - 3.87% per year and their propagating effects on the Chinese macroeconomic system to be a 1.38% - 1.68% annual loss in total direct and indirect output, which amounts to 17,323 - 21,082 RMB billion. Several infrastructure sectors - electricity, the heat production and supply industry, gas production and supply, the water production and supply industry - are indirectly affected owing to the effects of supply chain disruptions. Taking the above analysis one step further, this thesis explores how climate disaster risks may change over the period 2016 - 2055, using flooding as a case study. A global river routing (CaMa-Flood) model at a spatial resolution of 0.25° x 0.25° is applied and downscaled for China, using the daily runoff of 11 Atmospheric and Oceanic General Circulation Models (AOGCMs). Combining the flood analysis with the infrastructure database, this research demonstrates the changing locations of exposed infrastructures and their dependent customers. We find that by 2055, the number of infrastructure assets exposed to increasing probability of flooding under RCP 4.5 are 41, 268, 115, 53, 739, 1098, 432 for airports, dams, data centres, ports, power plants, rail stations, reservoirs respectively - almost 8% of all assets for each sector. The lengths of line assets exposed to increasing flood hazards are 14,376 km, 32,740 km, 102,877 km and 25,310 km oil pipelines, rail tracks, roads and transmission lines respectively. Under RCP 8.4, the numbers increase to 51, 301, 137, 71, 812, 1066, 424 for point assets. Linear assets increase to 19,938 km, 39,859 km, 122,155 km and 30,861 km. Further, we demonstrate that indirect exposure of customers reliant on those infrastructure assets outside the floodplain could also be high. The average number of customers affected by increasing flood probabilities are 54 million, 114 million and 131 million for airports, power plants and stations respectively. However, within this aggregate increase there is large spatial variation, which has implications for spatial planning of adaptation to flood risk to infrastructure. This is a first substantial study of flood impacts to infrastructure both in terms of direct exposure and their indirect implications. Lastly, to shed some light on the potential vulnerability of China's infrastructure system to climate impacts, this thesis develops a framework that identifies the drivers of infrastructure development in China using evidence from policy documents and a unique geospatial dataset for the years 1900 - 2010. Understanding these drivers will provide a useful foundation for future research in terms of developing infrastructure models that could project the locations of future infrastructure assets and networks in China, thereby quantifying how China's infrastructure exposure and vulnerability will change over time. Overall this research provides an integrated system-of-systems perspective of understanding network and economic vulnerabilities and risks to Chinese energy, transport, water, waste and digital communication infrastructures due to climate change. This is crucial in informing the long-term planning and adaptation in China.
2

Vizualizace modelování rizik v logistice / Visualisation for risk models in logistics

Hamšík, Filip January 2016 (has links)
This thesis focuses on development of web application for the visualization of waste transportation according to calculated data from optimization methods in GAMS application. Visualization shows the nodes and edges on Google Maps where it is possible to show more detailed information including diagrams and tables. The application provides filtering edges by their type, highlighting edges with dynamic setting, several different ways for user access and other features. Based on developed application there will be presented some recommendations applicable in future using of the model.
3

Transportörer och transportköpares väg mot fullständig elektrifiering av tunga transporter : En fallstudie kring implementering och uppskalning / Carriers’ and transport buyers’ path towards complete electrification of heavy transports’ : A case study about implementation and scaling up

Jaktfalk, Linnéa, Arvidsson, Julia January 2024 (has links)
Transporter står idag för en stor andel av Sveriges koldioxidutsläpp. Det gör att logistikfrågor blir extra viktiga då vidareutveckling och omformning av logistiksystem kan göra stor skillnad. Elektrifiering av fordon är en framtida lösning på problemet. Däremot anses det fortfarande vara ett förhållandevis nytt och osäkert område och det finns idag få exempel på implementering av elektrifierade fordon. Transportören Renall och transportköparen Returpack är två framstående företag med starkt hållbarhetsfokus som agerar fallföretag för studien. De har högt uppsatta mål, däribland elektrifiering av en stor andel av sina fordonsflottor till 2030. Studiens syfte är därför formulerat som följande: Syftet är att utreda hur transportörer och transportköpare kan arbeta mot fullständig elektrifiering av tunga transporter. Studien är uppdelad i tre primära delar. Den första delen utvecklar en metodik för hur elektrifierade fordon ska implementeras i verksamheter för att sedan kunna skalas upp. Denna metodik har resulterat i tre primära delar. Den första delen är utformning av ett elektrifierat logistiksystem där större strukturförändringar i logistiksystemet måste göras med syfte att öka effektivitet, nyttjandegrad och förutsägbarhet. Den andra delen är utformning av fordonsflotta där beslut om lämpliga batterikapaciteter för varje enskilt fordon tas. Den tredje delen utformning av laddstrategi beslutar om lämplig laddstrategi utifrån fordons- och uppdragskarakteristik. Den utformade metodiken appliceras sedan på fallföretagens presenterade empiri för att resultera i rekommendationer för hur de bör utforma sina elektrifierade logistiksystem, fordonsflottor samt laddstrategier. Efter analys av lösningar som ämnar anpassa logistiksystemet till elektrifiering presenteras rekommendationer för fallföretagen utifrån deras specifika situationer. Det kan dock konstateras att en stark maktposition, ett välutvecklat systemstöd samt kompetens inom elektrifiering underlättar arbetet mot ett elektrifierat logistiksystem. Vid utformning av fordonsflottan presenteras det samlade resultatet av ekonomiska analyser samt bedömningar av genomförbarheten för respektive fordon. Resultatet påvisar att det för cirka hälften av fordonen är ekonomiskt fördelaktigt med ett mindre batteri men att detta oftast begränsas av brist på laddinfrastruktur och behov av flexibilitet vilket innebär behov av överdimensionering. Det samlade resultatet innebär att cirka 20% av fordonsflottan rekommenderas mindre batterier. Vid utveckling av laddstrategier är rekommendationerna liknande för fallföretagen vilket beror på att en laddstrategi är beroende av enskilda fordons karakteristik snarare än en aktörs roll. Fallföretagen rekommenderas att utveckla två primära laddstrategier: en return to base strategi för laddning mellan skift samt en on route strategi för laddning under pågående rutt. Därtill utvecklas även en kostnadsmodell för att kunna genomföra en kostnadsanalys av hur kostnader förändras vid byte från nuvarande bränsle till elektrifierad drivlina. Den visar att sänkning eller höjning av kostnader vid byte av drivlina varierar mellan olika fordonstyper och områden, men att lönsamhet kan uppnås i många fall. Däremot krävs ibland justeringar och förändringar av logistiksystemet. Främst ses att långa avtalsperioder och hög nyttjandegrad av fordonen är att föredra. Likaså ger minskade inköpspriser stort utslag på resultatet. / Transport related activities currently account for a significant portion of Sweden’s carbon dioxide emissions. This makes logistics issues particularly important, as further development and transformation of logistics systems can make a big difference. Electrification of heavy trucks is a future solution to the problem. However, it is still considered a relatively new and uncertain area, and there are currently few examples of the implementation of electrified heavy trucks. The carrier Renall and the transport buyer Returpack are two prominent companies with a strong sustainability focus, acting as case companies for the study. They have currently set ambitious goals, including electrifying a large portion of their heavy truck fleets by the year 2030. Therefore, the purpose of the study is formulated as follows: The purpose is to investigate how carriers’ and transport buyers’ can work towards complete electrification of heavy transports. The study is divided into three primary parts. The first part develops a methodology for implementing electrified heavy trucks in operations, with the goal of scalability. This methodology has resulted in three sub-parts. The first sub-part is the design of an electrified logistics system, where significant structural changes in the logistics system are necessary to increase efficiency, utilization, and predictability. The second sub-part involves designing the heavy truck fleet, including decisions on appropriate battery capacities for each individual heavy truck. The third sub-part focuses on designing a charging strategy based on truck and mission characteristics. The formulated methodology is then applied to the empirical data presented by the case companies, resulting in recommendations on how they should design their electrified logistics systems, heavy truck fleets, and charging strategies. Solutions aimed at adapting the logistics system to electrification are analyzed, which result in recommendations for the case companies based on their specific situations. However, it can be noted that a strong market position, well-developed system support, and knowledge in electrification can ease the transition to an electrified logistics system.In the design of the heavy truck fleet, the combined results of economic analyses and feasibility assessments for each vehicle are presented. The results indicate that for approximately half of the vehicles, it is economically advantageous to have a smaller battery. However, this is often limited by a lack of charging infrastructure and the need for flexibility, which necessitate overdimensioning. The combined result is that approximately 20% of the vehicle fleet is recommended to have smaller batteries.In the development of charging strategies, the recommendations are similar for the case companies, as a charging strategy depends on the characteristics of individual vehicles rather than the role of the operator. The case companies are recommended to develop two primary charging strategies: a return to base strategy for charging between shifts and an on route strategy for charging during the ongoing route. Lastly, a cost model is developed to conduct a cost analysis of how expenses change when transitioning from heavy trucks fueled by HVO or biogas to electrified heavy trucks. It shows that cost reduction or cost increase upon fuel conversion varies among different truck types and regions, but profitability can be achieved in many cases. However, adjustments and changes to the logistics system are sometimes necessary. Long contract periods and high vehicle utilization are particularly favorable. Similarly, reduced purchase prices have a significant impact on the outcome.

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