In this study a new method is introduced to produce bimodal grain structures in low carbon steels. This method is based on cold rolling of dual phase structures and appropriate annealing treatments. The difference in the recrystallization behaviour of ferrite and martensite yields a heterogeneous microstructure with a distribution of coarse and fine grains. These types of microstructures are of interest for optimizing the balance of strength and uniform elongation in ultra-fine grained low carbon steels.

As the global warming brings more and more disasters, controlling greenhouse gas emission is one of the main global crucial issues nowadays. As one of the main emitters in the world, China faces more and more international pressure to reduce the emission, so it is urgent to make the transition to a low carbon economy.At the same time, China has been going through the fast urbanization process as shown in the “Northam Curve”, and the current urbanization mode requires the demand of the carbon-intensive consumption, and could lead to the massive carbon emission as well. However, it is contradictory to the long-time sustainable development in China. So, under the current condition, the reduction plan needs to be fit in the Chinese demand, so it is very crucial, and requires innovation and creation to analyze the reduction factor and find the balance point between the urbanization and low carbon development mode. Regarding to the different urbanization rate and economic development modes characters between the East, Central, West part of China, this thesis uses inductive and deductive method to study. Firstly, it chooses one province from each region to investigate. Then it integrated urbanization factor into Kaya equation to study different factors impacts on the carbon dioxide emission in the three sample provinces. It also selected the co-integration econometrics method to study the equilibrium relationship between the carbon dioxide emission and other main factors. Through analyzing the current reduction plan, it explains and forecasts the possible emission in 2015. The result suggests that the anticipated carbon dioxide emission might be able to achieve under the transition to a low carbon economy mode. Different regions should have their own feasible plans through controlling the urbanization rate, slowing the economic development rate and through reducing the energy intensity, improving the energy structure.

No description available.

The provision of housing in rural areas has been identified as crucial for the long term sustainability of rural communities. However, there are questions about how rural developers are responding to legislative requirements to reduce carbon emissions, whether the fulfilment of a need for affordable housing in rural areas can be reconciled with higher energy performance and whether higher energy performance will affect thermal comfort when climate change is taken into account. To understand these issues a review of published and monitored case studies in rural areas of the UK was undertaken which highlighted a number of development models that might be applied by house builders in the Welsh context. An analysis of two exemplar projects in Pembroke Dock, West Wales, examined the following: the social, economic and legislative context of rural development; the significance of energy and carbon used to construct rural houses; and the quantity of energy required to keep rural dwellings at a comfortable temperature in a typical year. Dynamic thermal modelling was then used to investigate a number of design approaches highlighted in the earlier studies as significant including: increasing thermal mass; increasing south facing glazing; adjusting building form and the layout of the site; and higher levels of insulation. The application of these approaches on a housing scheme in West Wales established the benefits of incorporating thermal mass into the building fabric, maintaining a compact form and, where reasonable, using passive solar gain, to reduce heating load. This study identified that these approaches, if carefully combined, could achieve significant (i.e. 16.4%-29.8%) reductions in heating load without compromising the affordability of the original scheme. However, the study also identified that one possible consequence of improving the energy performance would be a reduction in thermal comfort as a result of higher internal temperatures. To gain a better understanding of this further modelling examined the potential for overheating using the following: current and future climate files; an algorithm based on window opening behaviour; detailed simulation of airflow; and bivariate data analysis techniques. The results from this study identified that thermal mass and ventilation techniques could be employed to address the issues of overheating.

The thesis contributes a more lucid understanding of the potential for interaction amongst different facets of sustainability in the context of building design, providing evidence that the assimilation of diverse and often seemingly unconnected aspects of sustainability is not the unassuming process implicit in the current sustainability discourse. Working inductively and with a focus on two sustainable principles (the current UK government sponsored sustainability agenda, low carbon design, and an alternative interpretation, adaptable design, whose literature is framed in a sometimes complementary, at others antagonistic fashion to the former), this thesis develops an understanding of interaction in building design processes, using publically available documentary evidence and a comparative case-study approach. The thesis describes and categorises instances of interaction arising in the twenty-three case study building design processes, demonstrating both the empirical existence of interaction and improving the theoretical conceptualisation beyond basic ideas of synergy and conflict. Interaction is noted as arising from both technical incompatibilities and project actors interpretation of the agendas themselves: a socio-technical issue. The thesis distinguishes multiple approaches adopted by design teams to managing the entanglement encountered. Interpreting these interaction strategies in their case context, factors driving the selection of a particular approach are inductively derived and combined to form a tentative conceptual framework. This framework aides a systematic comparison across project cases, facilitated by the crisp set qualitative comparative analysis (csQCA) technique. Projects are described as configurations of the identified conditions and, by operationalizing interaction in a manner consistent with case study observation and the existing literatures of adaptable and low carbon design, assessed for successfulness in reconciling the agendas. The technique identifies three causal pathways to successful reconciliations of adaptable and low carbon design. Finally, the thesis makes a methodological contribution, through an evaluation of the application of QCA to a novel problem space (socio-technical, project-orientated problems of the built environment). Through the richness of documentary data obtained for study, it also demonstrates the potential effectiveness of documents as primary sources in the field of building design, where they are often relegated to a supporting role.

Climate change has emerged as one of the most serious challenges faced by human beings. As manufacturing globalisation involves more and more emerging nations, a greater proportion of CO2 emissions is generated from developing countries. The dilemma between fast industrial development and carbon reduction makes firms in developing nations reluctant to take serious commitment and actions in CO2 emission reduction in their global manufacturing practices. From a theoretical perspective, low-carbon supply networks research is also still in its infant stage and needs more explorations and development. Therefore this research aims to address the research question: “How can supply networks in developing countries be developed to reduce carbon emission?” Especially it focuses on: • An influence process to engage companies in developing countries to reduce carbon emission • A typology of carbon emission assessments in supply networks • An initial process of implementing carbon-reduction projects in supply network The research adopts theory building approach based on multiple case studies. The units of analysis are carbon reduction project of focal firms and initiatives of Non-Government Organizations (NGO). Drawing upon the cases, this research develops a general framework for developing low-carbon supply network, including three parts namely network influence, network CO2 measurement, and network CO2 improvement (IMI), with the three process models accordingly proposed. In the ‘influence’ process, based on resource dependence theory (RDT), this research illustrates a categorization of influence choices and a typology of influence pathways, which both underpin the four-step influence procedure proposed later. In the ‘measurement’ process, this research proposes a goal-oriented carbon footprint measurement guideline. In the “improvement’ process, an initial framework to classify carbon reduction projects and implementation process model of these projects are both built based on the analysis of primary case studies and Carbon Disclosure Project (CDP) database which contains corporates’ carbon reduction practices. Overall this research makes contributions in the following aspects: (1) this research advocates IMI framework as a pathway to de-carbonize supply networks, contributing to manufacturing system’s evolution to sustainable paradigm; (2) It integrates the institutional, stakeholder and network theory in the context of de-carbonization, and extends the research scope of operations management; (3) The research contributes to life cycle assessment (LCA) literature by exploring supply network coordination during the LCA procedure; (4) The research also contributes to green supply chain literature by providing insights from firms’ de-carbonization projects in supply network. (5) In practice, the IMI three-process models can help practitioners to implement de-carbonization management, serving as a preliminary guideline to follow. The potential audience of this research can be MNCs, NGOs, government bodies, consultants, and any organization or individual who aim to change industrial system in the pursuit of climate change mitigation.

Floating wind technology has the potential to produce low-carbon electricity on a large scale: it allows the expansion of o shore wind harvesting to deep water, indicatively from 50-60 to a few hundred metres depth, where most of the worldwide technical resource is found. New design specifi cations are being developed for floating wind in order to meet diverse criteria such as conversion effi ciency, maintainability, buoyancy stability, and structural reliability. The last is the focus of this work. The mechanics of floating wind turbines in wind and waves are investigated with an array of numerical means. They demand the simulation of multiple processes such as aerodynamics, hydrodynamics, rotor and structural dynamics; understanding their interaction is essential for engineering design, verifi cation, and concept evaluation. The project is organised in three main parts, presented below. Aero-hydro-mechanical simulation, characterising the rigid-body motions of a floating wind turbine. An investigation of multi-physical couplings is carried out, mainly through EDF R&D's time-domain simulator CALHYPSO. Wave forces are represented with the potential- ow panel method and the Morison equation. Aerodynamic forces are represented by a thrust model or with the blade element momentum theory. Main fi ndings: Exposure of fi nite-angle coupling for semi-submersible turbines with focus on heave plate excursion; characterisation of the aerodynamic damping of pitch motion provided by an operating vertical-axis turbine. Dynamic mooring simulation, focussed on highly compliant mooring systems, where the fluid-structure interaction and mechanical inertial forces can govern line tension. EDF R&D's general-purpose, finite-element solver Code Aster is confi gured for this use exploiting its nonlinear large-displacement and contact mechanics functionalities. Main findings: Demonstration of a Code Aster-based work ow for the analysis of catenary mooring systems; explanation of the dynamic mooring eff ects previously observed in the DeepCwind basin test campaign. Aeroelastic analysis of vertical-axis rotors, aimed at verifying novel large-scale floating wind turbine concepts in operation, when aeroelastic-rotordynamic instabilities may occur. The finite-element modal approach is used to qualify rotor vibrations and to estimate the associated damping, based on the spinning beam formulation and a linearised aerodynamic operator. Main fi ndings: Characterisation of the vibration modes of two novel vertical-axis rotor concepts using the Campbell diagram; estimation of the related aerodynamic damping, providing information on the aeroelastic stability of these designs.

Low levels of energy access in sub-Saharan Africa and the acknowledgement of anthropogenic climate change have made sustainable energy products such as solar lanterns and efficient cookstoves a popular subject of international development programmes. At the same time, market-based approaches for distributing such ‘humanitarian goods’ have become increasingly prevalent. Based on ethnographic material from inside two development intermediaries, Global Village Energy Partnership (GVEP) International’s ‘Developing Energy Enterprises Project’ (DEEP) in Kenya and Uganda and SolarAid’s social enterprise ‘SunnyMoney’ in Malawi, this thesis argues that: 1) the complexity of applied market devices enhances inequalities between market actors; 2) the engendering of economic subjectivities within distribution chains can increase value-sharing; 3) there is space for both for-profit and non-profit ‘development’ intermediaries in marketisation processes, and; 4) further focus should be put on the promotion of domestic manufacturing. Stabilised market maps are used to present the activities of each organisation before turning to three frames of analysis that consider the problematisation, qualification and valuation of the energy products, the recruitment and training of supply chain ‘entrepreneurs’ and the specific market roles of development intermediaries, including provision of ‘brokerage’ services and as integral market actors. Bringing a theoretical vocabulary from economic sociology and science and technology studies into the arena of international development, the thesis reveals the extensive socio-technical configurations that constitute markets and create power asymmetries between actors. Without neglecting the vulnerabilities of the ‘bottom of the pyramid’ (BOP) as a ‘target group,’ it enhances our understanding of the shifts away from charity dependent beneficiaries’ towards ‘entrepreneurs,’ ‘customers’ and investment opportunities within sub-Saharan Africa.

A current discussion of winner and loser is the issue of low-carbon development toward sustainability. Biofuel, as granted an important role to curtail the carbon emission and secure energy supply, has been also involved in this discussion. However, unfortunately, a biofuel potential has been raising fear worldwide since the surge of its development favors large-scale patterns, which are bringing widely social-economical and environmental impacts. How to foster strengths and circumvent weaknesses to plan this sector is the core of this paper. China has emerged to be the second economic entity with huge appetite for energy. This study is expected to explain China’s experiences in this field with guidance of effective biofuel planning.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第17880号 / 工博第3789号 / 新制||工||1579(附属図書館) / 30700 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 松岡 譲, 教授 米田 稔, 准教授 倉田 学児 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM