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Transport PPP decisions in Korea : value for money assessment and risk quantificationPark, Ji Hong January 2014 (has links)
Value for money (VFM) assessment has been adopted worldwide as a public private partnership (PPP) decision methodology. In terms of quantitative assessment, this method considers only the public sector cost, assuming completion delay does not occur between delivery alternatives, so it is difficult to use where systematic completion delays in the conventional delivery are expected to occur like in Korea. Therefore, in this research a Modified VFM methodology was developed to consider completion delay as well as public sector cost, using the VFM assessment and the Net Present Value (NPV) technique. In addition, various risks including transferable risks (completion delay, construction cost and traffic volume risk) were quantified in order to examine the impact of the transferable risks on PPP decisions, through historical observations and a literature review. In total six case studies (2 National Highways, 2 National Expressways and 2 National Railways) were conducted, reflecting Build-Transfer-Operate (BTO) and Build- Transfer Lease (BTL), the most popular PPP options in Korea. The biggest difference between the BTO and the BTL options is that the private sector makes a profit from end users’ tariffs in the BTO option, whereas it makes a profit using the annual lease fee from the government in the BTL option. The most important finding is that a completion delay in the conventional delivery can be a decisive factor on the quantitative PPP decisions because of the resulting benefit difference between conventional delivery and PPP options. As this completion delay for conventional delivery becomes longer, the probability that PPP schemes are favourable increases. In addition, the critical completion delay, making the Modified VFM zero, varies depending on not only whether to include the construction cost risk and the traffic volume risk, but also on the PPP options considered. Another important finding is that, when including construction cost risk, the viability of PPP options in roads increases, whereas that in railways decreases. This is because the average winning bid ratio (winner’s price divided by estimated price) of turnkey/ alternative bids in roads, used in the calculation of the asset cost of the public sector comparator (PSC) according to the BTL guidelines of Korea, is higher than historical observations that include construction cost risk, whereas in railways it is lower than historical observations that include construction cost risk. This difference between roads and railways seems to arise from the fact that railways are usually delivered separately using six major work element contracts, while roads are usually delivered by a single contract, suggesting that separate contracts lead to greater cost overruns than a single contract. In addition, when reflecting traffic volume risk, the most appropriate delivery option, from a Government perspective, for road/railway cases with tariffs changes from the BTL to the BTO option. This is because traffic volume risk directly results in a shortfall in revenue, which makes the BTO option more favourable to the public sector. However, in the case of railways, the BTL option seems to be practically adopted because the revenue stream is so small that the BTO option is not affordable for the private sector, even considering the maximum governmental subsidy condition. For the success of a BTO project in Korea, a new traffic volume risk sharing scheme is also suggested, sharing revenue shortfall or excess according to the investment of each participant. Overall, this research suggests that, considering the transferable risks and the revenue stream size of each transport programme, the BTL option is the most appropriate for the National Railways, whereas the BTO is the most appropriate option for the National Expressways, provided that the BTO viability can be achieved in terms of the internal rate of return. With respect to the National Highway programme, the BTL option can be considered as an alternative to conventional delivery on a case by case basis. Finally, considering the land transport programme (roads and railways) of Korea, a meta-analysis indicates that the Modified VFM is positively influenced by project size, completion delay, benefit cost ratio, discount rate and consumer price index, whereas it is negatively influenced by the five year exchequer bond interest rate. In addition, the BTO option and Gyeonggi province (surrounding Seoul) respectively have a bigger positive influence on the Modified VFM than the BTL option and Gyungnam province (adjacent to Busan).
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Performance analysis of the HARQ dynamic decode-and-forward protocolMaagh, Stefan January 2015 (has links)
The explosive growth of data traffic in wireless communication systems comes together with the urgent need to minimize its environmental and financial impact. Therefore, the main objective in the field of green radio communication is to improve the energy efficiency of wireless communication systems with respect to the future performance demands on the wireless communication infrastructure. In this context, recent research in cooperative and cognitive communication techniques attracts particular attention. While cognitive radio improves spectral efficiency by enhanced spectrum utilization, cooperative communication techniques achieve remarkable gains in spectral efficiency by enabling the terminals to share their resources. In particular, creating virtual multi-antenna arrays by antenna sharing enables exploitation of spatial diversity gains and multiplexing gains within a network of single antenna terminals. This technique is particularly attractive for mobile wireless networks, since power and space constraints often prohibit the integration of multiple antennas into mobile terminals. This work studies the performance of the hybrid automatic repeat-request (HARQ) dynamic decode-and-forward (DDF) protocol in the half-duplex relay channel. The reason behind exploration of the HARQ-DDF protocol is that it achieves the optimal performance in terms of the diversity-multiplexing tradeoff (DMT) and the diversity-multiplexing-delay tradeoff(DMDT). However, DMT and DMDT are evaluated as the signal-to-noise ratio (SNR) approaches infinity. In practice, key performance measures are the fixed-rate outage probability and delay-limited throughput achieved at the SNR expected during operation. To this end, it is common practice to give the performance of the DDF protocol as a function of the source-to-destination channel SNR (SD-SNR). In this dissertation the focus is to study the performance of the HARQ-DDF protocol measured as a function of the SNR as seen at the destination (D-SNR). This approach enables the performance comparison with the HARQ-SISO and the HARQ-MISO protocol from an energy efficiency perspective on the system level. Furthermore, a novel variant of the HARQ-MISO protocol, the hybrid repeat-with-diversity-request (HARDQ) MISO protocol, is introduced. Considering outage probability as measure of reliability, closed-form solutions and simulation results show that the HARDQ-MISO and the HARQ-DDF protocol outperform the HARQ-MISO protocol from an energy efficiency point of view. From a delay-limited throughput point of view the HARQ-MISO protocol is beneficial. It is demonstrated that code-rate assignment allows to achieve significant performance gains in terms of delay-limited throughput. Furthermore, reducing the decoding cost using code-rate assignment techniques comes together with only negligible performance loss.
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The designation and display of British railway heritage in the post-War decadesLambert, Mark January 2017 (has links)
This PhD thesis details the ways in which objects which were deemed to represent Britain’s railway heritage were designated as important and subsequently displayed or stored by the state-owned British Railways, and its’ Parent organisation (until 1962) the British Transport Commission, in the post-war decades. I focus particularly on the period between nationalisation in 1948 and the opening of the National Railway Museum in 1975, when responsibility for the preservation of historic railway objects passed to the Department of Education and Science (with the exception of paper records, which became the responsibility of the Public Records Office from 1972). In this period, the British Transport Historical Records Office was established in West London (with branches and York and Edinburgh), whilst a series of temporary exhibitions of railway history at the Shareholder’s Meeting Room in Euston in the 1950s were followed by the establishment of new transport museums at Clapham, South London in 1961 and at Swindon in 1962. Attempts by the British Transport Commission to preserve and display aspects of Britain’s railway history - and particularly, from 1951, those of its Curator of Historic Relics John Scholes and its Archivist Leonard Johnson- intersected with the increasing enthusiasm for railways amongst the general population, exemplified by the advent of new societies catering for this interest in addition to those established prior to the war, and also for the growing popularity of transport history as a subject of scholarly interest. This in turn took place in the context of increasing technological change on the network, notably the closure of thousands of miles of railway lines (often rural branch lines) and the abolition of steam locomotives in favour of diesel or electric power. This thesis shows that railway enthusiasts, through the Consultative Panel for the Preservation of British Transport Relics from 1958 onwards, played an active role in advising the Transport Commission on the preservation of railway heritage, notably the selection of historic locomotives to be saved for posterity. This thesis considers in detail the work of the Joint Locomotive Preservation Committee in 1948-1949 and of the Consultative Panel for the Preservation of British Transport Relics between 1958 and 1968, and also the interrelated activities and museum displays of the Curator and Archivist of Historic Relics at the British Transport Commission (later the British Railways Board) between 1951 and 1974 (1972 in the case of the Archivist), including the museum displays at the Railway Museum in York, the Great Western Railway Museum at Swindon and the Museum of British Transport at Clapham.
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Strategic logistics outsourcing : integrated models for evaluating and selecting Logistics Service Providers (LSPs) : upstream/downstream supply chain comparisonAl-Khatib, S. F. S. January 2015 (has links)
This research aims to maximize the logistics outsourcing benefits through developing new hybrid models for evaluating and selecting Logistics Service Providers (LSPs). The growing demand for logistics outsourcing and the increase in the number and type of LSPs highlight the increasing importance of the LSP evaluation and selection process. Firms use various approaches to evaluate and select their LSP partners. Most of these approaches seem to have overlooked the strategic side of the logistics outsourcing process. Additionally, the uncertainty issue of data, the complexity of the decision and the large number of criteria involved increase the attractiveness of the Multi-Criteria Decision-Making (MCDM) approaches. A comparative literature review was used in order to identify crucial factors and methods that are used in logistics literature in fragmented ways and therefore, to establish and design a conceptual framework and models for logistics outsourcing. First, a long list of evaluation criteria was developed. Three main dimensions were identified: logistics performance, logistics resources and logistics services. Then a conceptual framework was developed using the three main dimensions with their related factors. Based on the comparative literature review outcomes, a number of integrated models have been developed and used to achieve this aim with emphasis given to FDEMATEL, FTOPSIS and FQFD techniques. Whereas the FDEMATEL technique contributed to construct influence relationships between factors under each dimension, develop impact-relationship maps and identify dependent and independent success factors (ISFs), the FTOPSIS technique used the weighted success factors to evaluate, rank and select the best LSP in three case studies. Twenty-one ISFs have been identified to be used in the final approach. These ISFs consist of eight LKPIs, seven logistics services and six logistics resources and capabilities. All of the factors were used to evaluate and select the best LSP alternative and ISFs were used to conduct the evaluation process. Different sensitivity analysis tests are used to confirm models’ robustness. Based on the outcomes of both cases, decision makers can use independent factors alone to evaluate and select the best LSP, which simplified the logistics outsourcing process in our study. The FQFD technique was used to link the LSUs strategic objectives with logistics requirements and the ISFs to develop a new strategic logistics outsourcing approach. Finally, two case studies representing the supply chain upstream and downstream are used to demonstrate the new hybrid approach effectiveness. The comparison of both cases’ findings highlighted their differences in terms of strategic objectives, logistics requirements and ISFs.
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Strategic risk and reliability assessment in the container liner shipping industry under high uncertaintiesSalleh, N. H. M. January 2015 (has links)
The container liner shipping industry (CLSI) can be defined as one consisting of a fleet of vessels that provides a fixed service at regular intervals between ports of call. It is noteworthy that the CLSI is remarkably acting as an artery in making contributions to the growth of the global economy. However, in an era of unprecedented global changes, the CLSI faces a variety of internal and external risks. Moreover, the reliability and capability of liner shipping operators (LSOs) vary under different environmental conditions. Consequently, it is important for LSOs to ensure that the safety and reliability of their internal operations as well as external environments through proactive assessment of their reliability and capability are intact. The literature indicates that disruptive events have been assessed and investigated by many researchers and practitioners whilst the root causes arising from external risks have not yet been fully identified. The aim of this research was to develop integrated frameworks for assessing risk and reliability in the CLSI under high uncertainties. As a result, three interlocking levels of analysis have been highlighted in this research: 1) business environment-based risk (BEBR), 2) organisational reliability and capability (ORC) of LSOs, and 3) punctuality of containerships. To achieve the aim, firstly, this research employed a combination of different decision-making methods (i.e. Analytic Hierarchy Process (AHP), Fuzzy Set Theory (FST) and Evidential Reasoning (ER)) for the assessment of the BEBR. The research outcomes are providing LSOs with a powerful decision-making tool to assess the risk value of a country prior to investment and strategic decisions. In addition, LSOs are also able to regularly assess the overall level of existing BEBR in a host country prior to development of mitigation strategies that can help to minimise financial losses. Secondly, this research employs the Fuzzy Bayesian Belief Network (FBBN) method for evaluating the ORC of LSOs. By exploiting the proposed FBBN model, LSOs are able to conduct a self-evaluation of their ORC prior to the selection of a strategy for enhancing their competitive advantages in the CLSI. A significant concern in container liner shipping operations is the punctuality of containerships. Therefore, thirdly, this research concentrated on analysing and predicting the arrival punctuality of a liner vessel under dynamic environments by employing a combination of Fuzzy Rule-Base (FRB) and FBBN methods. Finally, a probabilistic model for analysing and predicting the departure punctuality of a liner vessel was generated. Accordingly, from the outcomes of this research LSOs are able to forecast their vessels’ arrival and departure punctuality and, further, tactical strategies can be implemented if a vessel is expected to be delayed. In addition, both arrival and departure punctuality models are capable of helping academic researchers and industrial practitioners to comprehend the influence of uncertain environments on the service punctuality. In order to demonstrate the practicability of the proposed methodologies and models, several real test cases were conducted by choosing the Malaysian maritime industry as a focus of study. The results obtained from these test cases have provided useful information for recommending preventive measures, improvement strategies and tactical solutions. The frameworks and models that have been proposed in this research for assessing risk and reliability of the CLSI will provide managerial insights for modelling and assessing complex systems dealing with both quantitative and qualitative criteria in a rational, reliable and transparent manner. In addition, these models have been developed in a generic sense so that they can be tailored for application in other industrial sectors.
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Future perspective of electric bicycles in sustainable mobility in ChinaLin, Xiao January 2016 (has links)
The thesis seeks to analyse the electric bicycle (e-bike) transition phenomenon in China by applying the Multi-Level Perspective (MLP) Transition Theory and Multi-scalar Perspective MLP. The research is performed with abductive case studies drawn from mixed methods. Firstly, we synthesised secondary data to investigate the e-bike transition at the national level (China) and the city level (“mini” case studies of Beijing and Fuzhou) to explore the research questions of 1) Can socio-technical transition occur without deliberate policy support (RQ1)? 2) How can we explain the rapid emergence and enduring popularity of e-bikes in China (RQ2)? Then we performed exploratory research in Cardiff, UK and Nanjing, China using semi-structured interviews. The interview results are used to help design survey questionnaire in Nanjing case study. It is the key research step and addresses the following research questions: 1) How are e-bikes embedded in the current transport regime (RQ3)? 2) How much longer can e-bikes continue to be embedded in the transport regime (RQ4)? 3) What are the mechanisms underlying the rapid emergence of e-bikes (RQ5)? To analyse the data collected from the survey, Generalised Linear Models and Binomial Generalised Linear Models are adopted to investigate current mode choice behaviour and predict future choice. In the theoretical aspect, the thesis applied the Multi-scalar Perspective MLP, filling the gap that traditional MLP does not take into account geographical, socio-political heterogeneity. In addition, we paid attention to the individual role in travel mode behaviour. From a practical perspective, the thesis uses substantial empirical data to provide a comprehensive understanding of the e-bike transition. We invited various groups in the survey, including e-bike users, bicycle users, car drivers, pedestrians and traffic police. The thesis explores a wide range of influencing factors, such as user anxiety, feelings related to e-bike adoption, e-bike user charging behaviour, other travel mode users and traffic police attitude towards e-bike development which have not been studied in previous e-bike literatures. The main findings are: 1) The fast emergence of e-bikes in China is spontaneous, without direct policy support from governments; 2) E-bike transition in China begins with transformation pathway (P1), followed by de-alignment and re-alignment pathway (P2); 3) E-bike users in China are mainly young career-aged commuters and have a much higher education level than average, which are different from other countries; 4) E-bikes are well embedded in the current transport regime and they are adopted widely in many aspects of people’s daily lives, including commuting, going shopping, and collecting children; 5) The underlying reasons for the selection of e-bikes are they provide affordable personal mobility due to the advantages of effort saving, flexible trip times, time saving in traffic jams, and high accessibility, whereas environmental and health factors are negligible; 6) E-bikes are possibly an intermediate mode on Nanjing’s motorisation pathway.
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Staggered deliveries in production and inventory controlHedenstierna, Carl Philip January 2016 (has links)
This thesis investigates production-inventory systems where replenishments are received every period (for example every day or shift), but where production plans are determined less frequently (weekly, fortnightly, or monthly). Such systems are said to use staggered deliveries. This practice is common in industry, but the theoretical knowledge is limited to a small set of inventory models, none of which include capacity costs. This thesis uses time series analysis to expand our understanding of staggered deliveries from the perspectives of inventory and production-inventory control. The contribution to inventory theory consists in the development of an optimal policy for autocorrelated demand and linear inventory costs, including exact expressions for costs, availability, and fill rate. In addition the thesis identifies a procedure for finding the optimal order cycle length, when a onceper- cycle audit cost is present. Notably, constant safety stocks are suboptimal, and cause both availability and fill rate to fluctuate over the cycle. Instead, the safety stocks should vary over time, causing the availability, but not the fill rate, to be constant. The contribution to production-inventory theory comes from two perspectives: First, an optimal policy is derived for quadratic inventory and capacity costs; second, four pragmatic policies are tested, each affording a different approach to production smoothing and the allocation of overtime work (once per cycle, or an equal amount of overtime every period). Assuming independent and identically distributed demand, these models reveal that all overtime or idling should be allocated to the first period of each cycle. Furthermore, it is shown that the order cycle length provides a crude production smoothing mechanism. Should a company with long reorder cycles decide to plan more often, the capacity costs may increase. Therefore, supply chains should implement a replenishment policy capable of production smoothing before the order cycle length is reduced.
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An exploration of relationship structures, their integration and value in maritime logistics networksLin, Shang-Min January 2015 (has links)
Maritime logistics plays a critical but often unnoticed role in global supply chains. Management of buyer-supplier relationships is central to the success of SCM. Therefore, as the essential part within the global supply chain relationships, it is important to study the inter-organizational relationships in maritime logistics network. The dominant consideration of relationship management research in maritime logistics has been focused on a dyadic level, and little research has looked at this issue from a network view. In addition, bringing about higher value through the process of complex exchange in business has been recognized, but seldom been examined empirically, neither has been the relevance between service complexity and the relationship strength. This thesis thus aims to explore the relationship structure and the value generated within the maritime logistics from a network perspective, mainly considering the service complexity within a varied of influential factors. Mixed methods approach has been adopted, using semi-structure interviews, quantitative questionnaire survey and social network analysis. The research framework based on logistics triad is established, and rich insights were obtained from industry. This leads to the evaluation of the relationship strength in maritime logistics networks, the association between service complexity and the nature of relationship in them, and the value generated in the networks, by using three-level analysis and six-dimensional measurement for relationship strengths. In terms of the major findings, this research identifies that not every link has the same level of integration in the network. A range of contingency factors affecting relationship strength are recognised. There is generally a positive correlation between service complexity and relationship strength, although some links do not demonstrate this. Likewise, there is an affirmative correlation between service complexity and value perceived. Nevertheless, only the values perceived by freight forwarders in each types of service are statistically significant. Until now, there has been very little consideration of using network perspective to measure and analyse the relationship dynamics and value generated in line with different service complexity in the maritime logistics, and therefore this thesis represents a clear contribution to the literature.
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An empirical investigation in the decision-making processes of new infrastructure developmentDehe, Benjamin January 2014 (has links)
The aim of this research is to present and discuss the development and deployment of Lean thinking models and techniques applied to improve the decision-making within the planning and design processes of new infrastructures, within a healthcare organisation. In the UK, healthcare organisations are responsible for planning, designing, building and managing their own infrastructures, through which their services are delivered to the local population (Kagioglou & Tzortzopoulos, 2010). These processes are long and complex, involving a large range of stakeholders who are implicated within the strategic decision-making. It is understood that the NHS lacks models and frameworks to support the decision-making associated with their new infrastructure development and that ad-hoc methods, used at local level, lead to inefficiencies and weak performances, despite the contractual efforts made throughout the PPP and PFI schemes (Baker & Mahmood, 2012; Barlow & Koberle-Gaiser, 2008). This is illustrated by the long development cycle time – it can take up to 15 years from conception to completion of new infrastructure. Hence, in collaboration with an NHS organisation, an empirical action research embedded within a mixed-methodology approach, has been designed to analyse the root-cause problems and assess to what extent Lean thinking can be applied to the built environment, to improve the speed and fitness for purpose of new infrastructures. Firstly, this multiphase research establishes the main issues responsible for the weak process performances, via an inductive-deductive cycle, and then demonstrates how Lean thinking inspired techniques: Multiple Criteria Decision Analysis (MCDA) using ER and AHP, Benchmarking and Quality Function Deployment (QFD), have been implemented to optimise the decision-making in order to speed up the planning and design decision-making processes and to enhance the fitness for purpose of new infrastructures. Academic literatures on Lean thinking, decision theories and built environment have been reviewed, in order to establish a reliable knowledge base of the context and to develop relevant solutions. The bespoke models developed have been tested and implemented in collaboration with a local healthcare organisation in UK, as part of the construction of a £15 million health centre project. A substantial set of qualitative and quantitative data has been collected during the 450 days, which the researcher was granted full access, plus a total of 25 sets of interviews, a survey (N=85) and 25 experimental workshops. This mixed-methodology research is composed of an exploratory sequential design and an embedded-experiment variant, enabling the triangulation of different data, methods and findings to be used to develop an innovative solution, thus improving the new infrastructure development process. The emerging developed conceptual model represents a non-prescriptive approach to planning and designing new healthcare infrastructures, using Lean thinking principles to optimise the decision-making and reduce the complexity. This Partial & Bespoke Lean Construction Framework (PBLCF) has been implemented as good practice by the healthcare organisation, to speed up the planning phases and to enhance the quality of the design and reduce the development cost, in order to generate a competitive edge. It is estimated that a reduction of 22% of the cycle time and 7% of the cost is achievable. This research makes a contribution by empirically developing and deploying a partial Lean implementation into the healthcare‟s built environment, and by providing non-prescriptive models to optimise the decision-making underpinning the planning and design of complex healthcare infrastructure. This has the potential to be replicated in other healthcare organisations and can also be adapted to other construction projects.
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An evaluation of solution design in logistics outsourcingGibson, Richard January 2011 (has links)
Outsourcing within the logistics and supply chain sector is perceived as a method to save money and improve client service levels. The outsourcing process exists within a highly stratified market of service provision and high value commercial arrangements may extend over many years. The client has a responsibility to define the strategy for their supply chain and agree distribution channel objectives which support the wider organisation’s brand delivery. There is a variety of solutions to satisfy these objectives of which outsourcing is one and should be accompanied by clear success criteria as well as a governance structure in order to yield a long term successful commercial arrangement. It is perceived that organisations may not follow an iterative approach towards outsourcing and that failing to adhere to these principles results in a lack of satisfaction for both parties evidenced by high contract turnover rates. This Phd thesis has investigated the issue of solution design within outsourced logistics amongst a group of 400 senior logistics managers through case studies, interviews and a three round Delphi survey. The hypothesis for this investigation was ‘the length and stability of an outsourcing relationship is directly related to the amount of effort expended by the customer in designing their logistics solution’. It was found that clients develop logistics strategy in varying degrees and over varying timescales. Clients measure the cost of supply chain activities with varying frequencies and few follow a straight forward method to define the parameters of a successful supply chain. Within outsourcing arrangements, governance and the management of change were poorly interpreted and executed. The current and future stratifications of logistics service offerings relied on a degree of collaboration between the pursuant parties and it was difficult to determine the effectiveness of these approaches when the balance of power between the parties was so unequal. Both clients and service providers were found to be poorly prepared to grasp the opportunities presented by the rising costs of energy and the future demands of reducing carbon intensity within the sector. Contributions were defined in terms of service level stratification and likely risk, behaviours and a toolkit for clients to observe when working within the outsourced environment as well as the opportunities presented by the changes currently influencing the sector. In conclusion, the hypothesis was found to be valid and the important role the client has to play in specifying and managing their logistics service provision was applicable across the logistics and supply chain industry.
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