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Abstract Urban transformation is vital to global sustainable development as humans increasingly come to dwell in cities. Within cities, the mobility sector promises the highest potential of carbon emission reduction. The disruptive business innovation brought about by the advent of app-based smart-sharing systems is emancipating collaborative consumption of mobility at larger and deeper scales, ranging from car-pooling, expanded electric vehicle (EV) use to bike-sharing. Synchronizing the existing yet under-realized low-carbon transport modes in cities, such as public transport, with emerging and diversifying app-based sharing mobility business models, offers huge potential to transform urban mobility toward sustainability. Yet, the rapid business expansion and innovation of the sharing mobility companies have profoundly challenged existing socio-economic relationships, knowledge systems and physical infrastructures in cities. This study explores the synergy between the social-ecological innovation in the sharing economy and the sustainable development of urban systems, using empirical data from three business cases in the emerging sharing mobility sector – in modes of ride-sharing, EV-sharing and bike-sharing - of Shanghai, China. It indicates that there is a strong co-evolution mechanism between the transformation towards more sustainable city at the macro-level and the business ecosystem innovation towards greener and smarter transport at the meso-level. We argue that the two level transformations, triggered by the disruptive innovation of the sharing economy and led by urban transformation towards sustainability, mutually influence each other and re-enforce sustainable values and practices in the fast changing urban context and business innovations in Shanghai.

Abstract The aim of this study is to identify significant risks for the renewable energy investment projects. In this regard, a novel hybrid multi-criteria decision-making (MCDM) model has been proposed based on hesitant linguistic terms and alpha level sets. This model has three different phases. Firstly, the dimensions and criteria are defined regarding the renewable energy investment risks. In the second part, the significance levels of these factors are calculated with the help of hesitant interval type-2 fuzzy (IT2F) DEMATEL-based ANP (DANP). Finally, the types of investors by the risk awareness entitled high, moderate, and low are ranked while using hesitant IT2F QUALIFLEX. In all analysis, alpha level sets are taken into consideration. The results demonstrate that organizational effectiveness and cost efficiency are the most prominent factors for renewable energy investment. On the other side, moderate risk should be taken in these projects. It is recommended that the departments within the company should be compatible with each other for the renewable energy investment projects to be more successful. For this purpose, necessary actions should be taken to improve communication between departments. Another important point is that cost control should be done effectively to contribute to the performance of the renewable energy investment projects.

El món s'enfronta actualment a un dels majors desafiaments en la història de la humanitat: l'escalfament global. La transició cap a les energies renovables és crucial per al desenvolupament sostenible. Al mateix temps, al voltant de 750 milions de persones no tenen accés a l'electricitat. Així, la humanitat s'enfronta a un doble problema: proporcionar un accés més fàcil a l'electricitat i assegurar-se que aquesta energia prové de fonts netes per evitar un desastre climàtic. Aquesta tesi explora el potencial de les microrredes d'energia renovable per millorar l'accés a l'electricitat en els països en desenvolupament. La primera part és una introducció general i una revisió de l'estat de l'art de les tecnologies actuals de microrredes, incloent-hi sistemes fotovoltaics, eòlics i petites hidroelèctriques, il·lustrats amb exemples de projectes reeixits a tot el món. La segona part se centra en el potencial de les microrredes d'energia renovable a Jacmel, Haití. L'estudi inclou una anàlisi detallada del panorama energètic existent, els patrons de demanda, l'anàlisi de costos i la viabilitat d'integrar tecnologies renovables. Utilitzant el programari HOMER, es comparen diferents escenaris mitjançant simulacions per optimitzar l'eficiència, el cost i l'impacte ambiental. Els resultats demostren que la incorporació de microrredes d'energia renovable pot millorar significativament la fiabilitat energètica i reduir les emissions de carboni. Aquest estudi integral proporciona valuosos coneixements sobre els aspectes tècnics i econòmics de la implementació de sistemes d'energia renovable en regions en desenvolupament, contribuint als objectius més amplis de transició energètica d'Haití. Destaca els beneficis de les microrredes renovables en la millora de l'accés i la sostenibilitat energètica, servint com a model per a regions similars a tot el món.

A promising alternative to either chemical or sensible heat energy storage systems is the latent heat thermal energy storage (LHTES) due to its superiority in many design aspects such as the high storage capacity as well as chemical stability and relatively low cost. Due to its potentials to overcome the problems of instability and intermittency of energy through using phase change material (PCM), latent heat energy storage has been used in a variety of practical applications. However, most of the phase change materials possess poor thermal conductivity resulting in modest charging/discharging rate. To overcome this deficit, high porosity metal foam is used to improve the overall thermal conductivity of the phase change materials leading to enhancing the heat transported, and hence, promoting the PCM melting and solidification.This proposal has been utilised to improve the performance of a latent heat thermal storage system having a parallel/staggered tube-bundle structure filled with paraffin as a PCM, where an open-cell copper foam is compounded to the paraffin wax. The PCM unit is charged/discharged using a relatively hot/cold water stream flowing across the tube-bundle units. The feasibility of such a configuration is examined numerically through simulating the proposed PCM-metal foam composite units and their surrounding shell computationally. The ANSYS Fluent CFD commercial code has been employed to solve the volume averaged Navier-Stokes equations taking into account the local thermal non-equilibrium expected to occur between the solid metal foam matrix and the paraffin phase-change material. The impact of some design and operating parameters on the charging/discharging performance has been tested including the water flow strength as well as the tube-bundle configuration. The currently proposed design of LHTES system has been found not only easy to configure but practically efficient as well, where the charging/discharging rate can be remarkably boosted through wise selection of design parameters.

Energy performance contracting is increasingly employed to promote energy conservation toward sustainable development. This study characterizes these services in China through an analysis from 2011 to 2020 that reveals imbalances in the energy services company (ESCO) sector with respect to trade route, customer base, and energy conservation technology. More specifically, analyses of inter- and intra-province trade networks show that Beijing was the lead provider of ESCO projects, whereas Hebei was the lead customer. Jiangsu, Liaoning, and Inner Mongolia have risen to be new significant players during the 13th Five Year Plan (FYP) period (2016–2020). Although a wide range of energy conservation measures were deployed, ESCO projects were most prevalent in the industrial sector, with particular emphasis on residual heat, pressure and gas recovery. However, the building sector become an increased focus for ESCO projects during the 13th FYP. We further find that national guidelines alone may not lead to significant advances in energy conservation without additional and complementary provincial support. Such heterogeneity, especially at the provincial level, may help explain observed imbalances in ESCO projects. While prior studies usually focus on national guidelines, the more general implication and call of our study is that greater attention should be placed on subnational (provincial) guidelines around energy conservation.

Centralized routing is beneficial as it provides a global network view to plan and achieve the best and effective path for real-time traffic. With the rapid development of software defined networking, centralized routing has aroused more and more concern of researchers. An effective centralized load balancing routing (LBR) for wireless mesh network considering energy harvesting is proposed in this letter. LBR can provide flexible and optimal routes for real-time traffic. To minimize the long-term weighted sum cost which includes load and energy condition, LBR considers the queue length, channel condition, energy cost and energy harvesting. The problem of making dynamic decisions based on real-time traffic conditions is solved by the dynamic programming approach. Simulation results demonstrate the advantages of LBR.

There are some risks in renewable energy investments, such as legal, technology and financial issues. Hence, appropriate actions should be taken to minimize these risks. However, each of the measures to be taken for the management of risks creates new costs for businesses. Therefore, to ensure the financial sustainability of the projects, measures for the most important risks should be taken at the first stage. Because of this situation, it is vital to make a priority analysis for the risks faced by renewable energy projects so that it can be possible to increase the effectiveness of risk management. Accordingly, in this study, it is aimed to examine the risks and rewards regarding sustainable investment decisions for renewable energy projects. In this scope, a novel model is generated by integrating different techniques. In this process, the evaluations of six different experts are taken into consideration. First, missing evaluations for the sustainable investment decisions in renewable energy are estimated with neuro decision-making and collaborative filtering. Secondly, the weights of the risk factors of sustainable energy investments are computed with neuro quantum spherical fuzzy (QNSLF) DEMATEL with golden cut. Thirdly, reward alternatives for sustainable decision making are analyzed with Neuro QNSLF TOPSIS with golden cut. This study contributes to literature by determining the most important risks for renewable energy projects by an original decision-making model. Another important novelty of this study is that a new technique called neuro decision-making has also been developed. In this technique, the facial expressions of the experts who evaluate are taken into consideration. It is defined that technological changes have the greatest significance. Additionally, governmental incentives are found as the most essential reward to improve sustainable investments in renewable energy. Thus, for the effective management of these risks, appropriate actions should be taken. It is also obvious that the competitiveness of companies that fall behind this new technology will decrease. In this context, these enterprises need to take the necessary measures to manage the technology risk to be sustainable in the long term.

The deep-sea, defined as the area 200 m below the surface, is facing emerging chemical, physical and biological stressors. Currently, very little is known regarding deep-sea ecosystems both globally and in the Arctic. In this thesis I undertook a literature review on the current understanding of global deep-sea ecosystems through the use of stable isotopes. Specifically, I synthesized the available literature on spatial variation, energy pathways, depth, temporal variation, feeding behaviour, niche, trophic position and body size isotopic trends. This thesis then presents a case study examining the isotopic niche of five teleost and two decapod species within Arctic deep-sea food webs across the localized latitudinal gradient of Baffin Island. Spatial variation in isotopic niche was quantified using 13C and 15N for seven deep-sea species at three locations on Baffin Island, Nunavut to determine whether the “Latitudinal Niche Breadth Hypothesis” which states that niche breadth should increase with latitude holds true in the Arctic. Overall, isotopic patterns in global deep-sea ecosystem are variable; consistent trends are not observed across all taxa and habitats. It was concluded that niche breadth did not consistently increase with latitude in the eastern Canadian Arctic; localized conditions (e.g. sea ice, temperature) and individual condition (e.g. hepatosomatic index) may contribute more to a species’ niche than latitude. Overall, this thesis improves our understanding of deep-sea ecosystems globally, contributes baseline data for future monitoring, and by investigating multiple species and locations it will provide input on how climate change may impact Arctic food web diversity, energy dynamics and ecosystem structure to aid in sustainable fishery development.