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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.
51

Service quality indicators for business support services

van Ree, H. J. January 2010 (has links)
Quality is critical to corporate success as it plays a vital role in improving organisational productivity. It can be defined as ‘the totality of inherent characteristics of a product or service that bear on its ability to increase the demand for that product or service at a fixed price’ and can best be measured by capturing customer perceptions of the performance of those characteristics. Customising the SERVPERF methodology to measure service quality in a business-to-business context and subsequently testing it on both customers and suppliers of cleaning, catering and security services, the research led to a number of important and valuable insights concerning the service quality construct in a business-to-business environment. First, service quality in relation to cleaning, catering and security services consists of nine clear dimensions: reliability, clout, reputation, awareness, competitiveness, collaboration, accessibility, competence and assurance. The nine-dimensional construct identified shows high reliability and good validity in statistical terms. Furthermore, eight of the nine service quality dimensions are strongly or moderately yet significantly related to customer perceived service quality and customer satisfaction - clout being the exception. The same eight dimensions are significantly, but moderately related to purchase intention - suggesting that that there might be other constructs important in making a purchase decision (e.g. the costs of service delivery). Third, relating the nine service quality dimensions to the financial performance of supplier organisations, it was identified that six of the nine dimensions have significant relationships with one or more of the ten financial performance measures investigated - reliability, accessibility and competence being the exceptions. Finally, it was identified that customer organisations have significantly lower perceptions of the service quality they receive than do supplier organisations for competitiveness, collaboration, accessibility and competence. Moreover, customer perceived performance is significantly lower than customer perceived importance for eight of the nine service quality dimensions. For customer organisations, the empirical findings can be used to develop a framework of Service Quality Indicators, which can be used for monitoring and benchmarking service quality perception. For supplier organisations, the findings can be used for resource-allocation decisions pertaining to improve service quality, customer satisfaction and ultimately purchase intentions. It should be noted that the research is exploratory in nature and has only begun to address the many issues that are important in the management of business support services, but the questions addressed - what quality dimensions are important for customer satisfaction and what quality dimensions are important for supplier performance - are arguably among the most important in service quality management.
52

Job shop scheduling with flexible maintenance planning

Struijker Boudier, Ivar January 2017 (has links)
This thesis considers the scheduling challenges encountered at a particular facility in the nuclear industry. The scheduling problem is modelled as a variant of the job shop scheduling problem. Important aspects of the considered problem include the scheduling of jobs with both soft and hard due dates, and the integration of maintenance planning with job scheduling. Two variants of the scheduling problem are considered: The first variant makes the classic job shop assumption of infinite queueing capacity at each machine, while such queueing capacity is non-existent in the second variant. Without queueing capacity, the scheduling problem is a variant of the blocking job shop problem. For the non-blocking variant of the problem, it is shown that good solutions can be obtained quickly by hybridising a novel Ant Colony Optimisation method with a novel Branch and Bound method. For the blocking variant of the problem, it is shown that a novel Branch and Bound method can rapidly find optimal solutions. This Branch and Bound method is shown to provide good performance due to, amongst other things, a novel search strategy and a novel branching strategy.
53

The value of pharmaceutical R&D projects under uncertainty and drug approval policy

Wei, Wei January 2016 (has links)
Pharmaceutical R&D projects often have the characteristics of irreversibility on investment, flexibility of investment timing, and uncertainty in cash flows. In this thesis, the real options approach is used as the evaluation tool for these projects and three continuous-time investment models are developed. In chapter 4, we discuss the effects of the investment lag and commercialization flexibility on the investment decisions under uncertainty. Chapter 5 examines which organizational structures, the decentralized or centralized pharmaceutical R&D project, are more socially desirable in terms of early investment and higher project value. Chapter 6 considers whether adding a time constraint on the drug development process will increase the investment incentives and how remuneration level will influence the quality of the products, as well as the timing of commercialization.
54

Investigating the potential of a three dimensional concurrent engineering based approach to environmental new product development

Mombeshora, Idai Mendy January 2016 (has links)
The increasing importance of environmental issues in new product development heightens the significance of the three dimensional concurrent engineering (3DCE) concept as a platform that allows for the assimilation of environmental considerations into the new product development process. While environmental concerns can be integrated without 3DCE, the added element of early supply chain consideration that is inherent in 3DCE is critical to the successful environmental new product development (ENPD) efforts as the environmental performance of a product is the consolidation of its environmental impact through all the stages of its lifecycle; making it dependent on the supply chain. This study aimed to explore and investigate the potential role and utilisation of the supply chain, through a 3DCE-based approach, during ENPD. It took the form of a mixed method study composed of a multi-case study, exploring supply chain management and the new product development process, and controlled experiments, exploring the impact of early supply chain design during environmental new product development. It was found that having the procurement function manage supply-side interactions and the design function practice preliminary supplier selection enables ENPD through early supply chain design. The key is the availability of supplier-specific information (supplying company and product information) and the effective use of the information. The information is made available through supply chain information sharing, a process that is hampered by the willingness to share and information availability. Using technology, mapping the supply chain for visibility and consolidating industry efforts were found to aid the information sharing. The findings and outputs of this study simultaneously expand the knowledge surrounding the utilisation of the supply chain during the integration of environmental considerations into the product development process, improve industry understanding of various organisational issues that surround the ENPD activity and offer new pragmatic mechanisms to support organisational ENPD efforts.
55

The meaning and management of product-service quality

Backholer, Charlotte January 2014 (has links)
This thesis explores how quality is measured when a combination of product and service are being provided and investigated how these processes are managed. Relatively little research exists on measuring quality of Product Service Bundles (PSB). This thesis attempts to address this gap by carrying out multiple, cross-sectional case study research on a variety of business-to-business (B-2-B) PSB providers situated within the UK. The thesis makes three principal contributions. First, some aspects of quality need to be considered ‘core’ when providing an integrated PS offering and this work identified four that were predominant: physical product, product performance, service experience and service outcome. The empirical work also confirmed that these aspects need to be integrated in some manner and measurement was a critical part of this process. Second, building on this question of integration, the analysis of the eight pilot cases and four main project cases illustrated that the development of a quality assurance system (QAS) to measure the quality aspects of the PSB is fundamental to its success. The empirical work identified the role of the QAS, predominately focused on the product elements. Although, the QAS had the capability to manage the service element of the integrated PS offering, the research findings identified this was underutilised. Third, the management of the quality of an integrated PS offering, via the QAS, etc., must recognise the complementary nature of contractual and relational governance and then actively develop mechanisms that address and intertwine both dimensions of inter-organisational exchange. While existing research has considered them separately, this research considered them jointly, as part of the PS offering. Finally, several potential avenues of further work have been identified but, in particular, a longitudinal study would help to determine how the life cycle of the PSB influences the management of PS quality.
56

Resource-independent computer aided inspection

Mahmoud, Hesham January 2016 (has links)
Quality is of paramount importance when establishing and maintaining market share in any manufacturing sector. Measurement is a critical tool in ensuring product conformance and is a major enabler in the control of manufacturing processes to improve and maintain quality. Furthermore, measurement is evolving into a value-adding process in its own right and the gained measurement knowledge has become crucial for both design and manufacturing stages. Despite this ever increasing importance, measurement planning and execution is still carried out with great reliance on manual operations and ambiguous practice guidelines utilising tools and software that are very specific to the individual pieces of equipment used in the measurement process. In addition, in industry, measurement plans are defined in isolation instead of in an integrated and interoperable manner with other manufacturing activities. This research aims to formulate an interoperable integration framework for defining measurement processes through the introduction and realisation of resourceindependent measurement specifications (REIMS). REIMS is a data model that represents both measurement features and operations to enable their exchange between computer aided for x (CAx) applications. REIMS enables measurement process definitions to be exchanged between various measurement geographical locations and resources within a distributed manufacturing system. It, therefore, reduces the recently identified variability due to the measurement planning phase that varies depending on the experience and skills of the measurement operators. REIMS also removes an integration barrier at the measurement planning-execution interface and assists in obtaining consistent measurement knowledge. Comparable measurement knowledge is crucial for taking proper decisions for improving both design and machining phases. This thesis uses system engineering methods for analysing the measurement process and its data flow and requirements. As a result of this analysis, the REIMS data model has been developed based on the STEP modelling and implementation mechanisms to formulate a computer interpretable format of the measurement process data. STEP-based methods have been selected as the framework as they have been previously validated for interoperable data exchange between design and machining applications. The theoretical basis of REIMS is the concepts and definitions presented in the ISO standardised documents for “geometric product specifications (ISO GPS)” as these documents, for the first time in the domain, consider design specifications and measurement activities in relation to each other. The REIMS data model has been realised and a prototype implementation has been designed utilising the CTC-01 test case encoded as an ISO10303-242 compliant model. This test case has previously been used by the national institute of standards and technology (NIST) for validating the exchange of design data including product manufacturing information (PMI) between different CAD systems and as such provides an authoritative example. The implementation framework uses C++ and ST-Developer to obtain the design information from the AP242 file data and demonstrates the ability of the REIMS data model to map design specifications into measurement features and to define the necessary measurement operations to complete the process definition. An ISO10303-21 compliant file has then been constructed from the REIMS data to establish the proposed data exchange mechanism. Based on the findings of this thesis, the REIMS provides a coherent, comprehensive and flexible framework for representing the measurement process. Through adoption of REIMS as the standardised framework for measurement planning, companies could ensure the consistency of the measurement knowledge that is gained and maintained in the enterprise regardless of the location or equipment. This would facilitate the spread the measurement process benefits throughout the digital factory with potential for cost saving due to resource fluidity, a significant decrease in plan translation errors and reducing the equipment specific training requirements.
57

Cutting patterns for efficient production of irregular-shaped pieces

Abeysooriya, Ranga Prasad January 2017 (has links)
The research presented in this thesis belongs to the subject area of operations research. The study investigates and utilises the solution methodologies known as heuristics and local search for three practical problems related to cutting and packing using irregular shapes and multiple bins. From an application point of view, the problems domains remain in manufacturing, specifically where minimising the resources is required to meet a particular outcome. Many manufacturing processes begin with cutting desired items from a stock sheet of material, hence this study focuses on generating efficient cutting patterns, which is applicable in the manufacture of furniture, shoes, tools, ships, and garments. First, we consider designing an efficient solution procedure for solving two-dimensional irregular shape single bin size bin packing problem and two-dimensional irregular shape multiple bin size bin packing problem. Our intention is to consider alternative strategies such as placement policies, hole-filling and handling rotation of pieces; particularly with unrestricted rotations. Despite the fact that both problems are widely applicable in sheet cutting, their consideration in the literature is limited. To our knowledge, only a few authors have attempted to incorporate the first problem with the unrestricted rotation of pieces while the second problem with unrestricted rotation has not been considered at all. Being applicable in the real world, both the problems require powerful algorithms to determine the arrangement of irregular pieces on stock sheets in order to minimise the material waste. In this thesis, our focus is on developing algorithms to solve each problem efficiently. These algorithms draw on concepts in computational geometry, computer science as well as operations research. We investigate a set of newly proposed single-pass constructive algorithms that builds a feasible solution by adding pieces sequentially to a packing area defined by a set of bins which can either be homogeneous or heterogeneous. Each problem has a large solution space due to the different combinations of bins and arrangements of irregular pieces. We adopt the optimisation power of local search methods and metaheuristics to find good solutions. As one of the useful heuristic procedures, we use the Jostle heuristic (JS) to solve irregular shape single bin size bin packing problem and irregular shape multiple bin size bin packing problem due to its promising performances in handling both allocation and placement decisions of the pieces together. The Jostle was used in earlier studies for solving irregular strip packing problems and in this study we adopt it first time to solve irregular bin packing problems. Also, our implementation of Jostle handles identifying promising orientation angles of the pieces using the newly proposed angled tuning mechanism when placing pieces. Experimental results reveal that the proposed algorithms can manage different variants of the problem and find solutions with good utilisation of material. For the third problem of this study, we consider multi-period irregular bin packing problem with use of residuals. This allows using leftovers of a certain period which are usable as input stock material for the next periods. Here, we expand the previous work on irregular bin packing algorithms for heterogeneous stock sheets to consider the inventory and production process of sheet cutting. We propose two models to test the impact of a variety of operational policies around the retention and reuse of residual materials in the sheet cutting process. It also examines the cost sensitivity of using residuals with respect to nine practical scenarios within those operational policies. The computational results demonstrate that the proposed multi-period approach with residuals derives better results than solving each order individually for a selected set of operational scenarios and disclose which policy would be more advantageous to operate in each scenario. The results facilitate developing a tool to guide the manufacturers to take effective decisions based on the scenarios applicable to their sheet cutting process.
58

Bootlegging in high technology R&D departments : from initiation to disclosure

Masoudnia, Yaser January 2012 (has links)
Bootlegging -the unauthorised projects initiated by an employee and directed toward innovation for the benefit of their organization -is an important aspect of innovation, because it is considered to be a great source of bottom-up innovation within organisations. Since it is clandestine and hidden from management and researchers, it has remained one of the least researched aspects of the innovation process. There are a handful of studies on the topic of bootlegging in the management literature – mainly based on one or a small number of case studies. The research suggests that bootlegging activity can lead to innovative new products and is seen in a positive light by a large majority of authors. However, the existing literature lacks empirical evidence and consensus among different authors on the various aspects of bootlegging such as reasons for bootlegging, underground operation, disclosure stage of bootlegging and its outcomes. Since bootlegging is a clandestine process, after careful consideration of a variety options, it was concluded that in-depth interviews with bootleggers is the most appropriate approach for studying the topic. Network sampling was applied to identify bootleggers and gain their trust. The researcher has utilised his network and attended several professional and engineering conferences to identify and approach bootleggers rather than contacting them through their managers and organisations. Subsequently, 55 in-depth semi-structured interviews were undertaken. The appropriate research methodology helped to shed light on these under-researched aspects of innovation. Cont/d.
59

A structured approach to modelling lean batch production

Davies, Robert Stephen January 2014 (has links)
A problem relating to the manufacture of automotive body panels concerns the appropriate choice of production size or batch quantity of a body panel production run that ensures a minimum inventory profile is maintained while not compromising production efficiency. Due to underlying variation within the body panel production process it is difficult to determine a relationship between the batch quantity and production efficiency. This thesis determines the appropriate production batch size through the creation of an iterative modelling methodology that initially examines the nature of the variation within the panel production process. Further iterations of the methodology apply appropriate analytical modelling methods until a satisfactory solution is achieved. The modelling construction is designed so that it is potentially applicable to a wider range of manufacturing problems. As there is variation inherent within the system, regression analysis, experimental design (traditional and Taguchi) are considered. Since an objective of creating the modelling methodology is the potential of apply the methodology to a wider variety of manufacturing problems, additional modelling methods are assessed. These include the operational research methods of mathematical programming (linear and non-linear and dynamic programming) and queuing systems. To model discrete and continuous behaviour of a manufacturing system, the application of hybrid automata is considered. Thus a suite of methodologies are assessed that assess variation, optimisation and networks of manufacturing systems. Through the iterative stages of the modelling approach, these analytical methods can be applied as appropriate to converge on to the appropriate solution for the problem under investigation. The appropriate methods identified to quantify a relationship between the batch production quantity and production efficiency include regression modelling and traditional experimental design. The conclusion drawn from the application of both methods is that relative to the inherent variation present in the production system, lower batch quantities can be chosen for production runs without affecting the production performance. Consequently, a minimum inventory profile can be maintained satisfying the objective of a lean system.
60

Increased energy efficiency in manufacturing systems using discrete event simulation

Solding, Petter January 2008 (has links)
Market demands are forcing industrial manufacturers to develop their production systems by increasing flexibility, improving quality and lowering production costs. With the help of simulation techniques the understanding of manufacturing systems can be enhanced and alternate solutions can be tested. Simulation has therefore played an important role in industrial development in recent years. New or improved simulation technologies, and new ways to use the available technologies, are still being developed. Energy related costs are often neglected by Swedish industry due to the low energy costs historically in Sweden, compared to other European countries. The developments of the energy market with uncertainty concerning future prices have increased the need for energy efficiency. Resources in manufacturing facilities need to be used in the most efficient way. The increasing use of computer-based tools for supporting production planning and control, as well as management and control of energy systems, has not been as beneficial as might first appear. These two types of tools are seldom integrated, which complicates the control of either system. A methodology for analysing the production system, the energy system and these systems interaction with each other, will enhance the possibility of improved control of the facility. This research has focused on formulating a methodology for more efficient use of energy in manufacturing plants, with main focus on electricity use. The methodology uses Discrete Event Simulation (DES) as a tool for applied analysis of manufacturing systems. Focus area of the study has been on the energy intensive foundry industry. The methodology aids the process of efficient working by identifying what processes are important, what activities have to be carried out and what types of analyses can be undertaken. A way to categorise equipment by energy usage is presented to simplify the procedures of collecting, presenting and using data in the simulation model. An approach to how the model can be built is described so that the simulation model can be used for analysis of energy use. To evaluate the methodology four case studies were carried out at different foundries in Sweden. It was found that the level of maturity between the different companies at the outset of the research project varied, regarding manufacturing and simulation as well as energy use. These differences enhanced the analysis in the way that specialised solutions had to be made to complete the analysis. The output from the simulation case studies showed that there is potential to reduce both electricity and power use in all foundries studied. The methodology, and the integration of Discrete Event Simulation, complements the use of energy models for industrial applications, since analysis can be made on the discrete production which is mimicked by the model. The range of applications that utilise Discrete Event Simulation in industry is also enhanced. The research study has successfully shown that energy data can be added to a simulation model and that the model can be built in a way that makes it useful for analysis of both production efficiency and energy use. The methodology presented can help companies reduce their overall energy use and peak power loads. This will not only reduce the total energy related costs for the companies but also the CO2 emissions, reducing the companies' overall environmental impact. To extend the methodology future research will be conducted to add optimisation techniques to the simulation models and to integrate the models with surrounding systems, such as Enterprise Resource Planning (ERP) systems and Load Management Systems (LMS). Future investigation is also needed to determine whether the methodology can be used for dynamic Life Cycle Assessments (LCA) where the production will contribute to the impact a product will have on the environment during its whole life cycle.

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