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Many manufacturing companies have long endured the problems associated with the presence of `islands of automation'. Due to rapid computerisation, `islands' such as Computer-Aided Design (CAD), Computer-Aided Manufacturing (CAM), Flexible Manufacturing Systems (FMS) and Material Requirement Planning (MRP), have emerged, and with a lack of co-ordination, often lead to inefficient performance of the overall system. The main objective of Computer-Integrated Manufacturing (CIM) technology is to form a cohesive network between these islands. Unfortunately, a commonly used approach - the centralised system approach, has imposed major technical constraints and design complication on development strategies. As a consequence, small companies have experienced difficulties in participating in CIM technology. The research described in this thesis has aimed to examine alternative approaches to CIM system design. Through research and experimentation, the cellular system approach, which has existed in the form of manufacturing layouts, has been found to simplify the complexity of an integrated manufacturing system, leading to better control and far higher system flexibility. Based on the cellular principle, some central management functions have also been distributed to smaller cells within the system. This concept is known, specifically, as distributed planning and control. Through the development of an embryo cellular CIM system, the influence of both the cellular principle and the distribution methodology have been evaluated. Based on the evidence obtained, it has been concluded that distributed planning and control methodology can greatly enhance cellular features within an integrated system. Both the cellular system approach and the distributed control concept will therefore make significant contributions to the design of future CIM systems, particularly systems designed with respect to small company requirements.

Construction waste minimization and management plays an efficient role in achieving sustainability by providing appropriate consideration to the environment, community, and social conditions by delivering built assets. The construction industry has a significant effect on the environment in terms of resource consumption and waste production. Recent statistics published by the UK Government disclose that the construction and demolition sector generates approximately 32% of the total waste in the UK, which is three times more than the waste generated by all households combined. Concrete has been a leading construction material for more than a century. However, current and on-going studies in the field of construction waste minimization and management mostly focus on general waste management or examine one specific method of waste minimization. While only a limited number of studies have been conducted to examine on-site concrete waste minimization, the literature reveals that research in this context is required. This research aimed to propose an on-site concrete waste minimisation framework (OCWMF) for construction projects, which could potentially be applicable and achievable in Iran. In this pursuit, six objectuves were determined to guide the research, which are: to identify the common methods on OCWM in the UK as a successful pattern in WM; to rank OCWM methods in UK; to rank OCWM methods in Iran; to identify the differences between common methods of OCWM in the UK and Iran and explore the possible causes of these differences; and to investigate the causes of differences in the favoured methods in the UK and the favoured methods in Iran. Finally, the last objective was to propose a framework for Iran. Both quantitative and qualitative strategies as well as a combination of qualitative and quantitative strategies were adopted for this research. Data was collected through face-to-face semi-structured interviews in the UK (N=5), a self-administered postal questionnaire survey in the UK (N=196 distributed, N=73 received), a self-administered postal questionnaire survey in Iran (N=196 distributed, N=110 received), and face-to-face semi-structured interviews in Iran (N=10). Interviewees were project managers, site superintendents, consultants, and engineers selected from the top 100 contractor companies and the top 100 consultant companies in the UK and in Iram. The questionnaire questions were developed on the findings of the literature review and the semi-structured interviews in the UK. Then, to examine the outcomes of interviews in Iran, three case studies in Iran was observed. Finally, emanating from study results, an OCWMF was developed and refined using discussions (N=2), a questionnaire (N=6), and interviews (N=7). Key findings that emerged from the study include: legislation and regulations in the UK are the main drivers for construction waste reduction; governmental initiatives in reducing waste, use of pre-fabricated building components, and education and training are the most recommended OCWM methods in the UK in terms of overall worthiness or spending to create savings or minimize waste; governmental incentives to reduce waste, education and training, and purchase management are the most recommended methods in Iran; the main differences between proposed OCWM methods in Iran and in the UK are in the use of pre-fabricated concrete elements (PCEs) and ready-mix concrete; the cost of using PCEs in the main cause of difference in methods between the countries; and the consultants and contractors involved in the case study were not interested in using PCEs in their projects due to the high costs involved despite the significant reduction in waste when this method is used. In conclusion, the framework proposed various remedies that could potentially be used for improving OCWM in Iran. This study has also made some recommendations for the industry, policy makers, and for further research. The content should be of interest to contractors, clients, and engineers.

This thesis is concerned with the subject of heuristic scheduling in the context of medium-sized batch and jobbing manufacture. A scheduling program involving up to 1500 jobs and 150 machines is described and the methods by which:conflicts were resolved and objective functions were measured is discussed. An account is given of the computation experience found in applying the proposed scheduling technique to 15 different problems. Precise despatching parameter control is applied to jobshop scheduling problems and the results presented in the form of reponse surfaces. The properties of the measured responses are examined using the techniques of Fourier and Walsh analysis and a model of 'regular' constituents of the surfaces is presented. The re:sponzue surfaces observed in job-shop scheduling problems are compared with the theoretical respcnse of a simple f lowshop problem and the points of similarity discussed Classical non-linear optimization techniques are introduced and applied to job-shop scheduling problems. A new approach to the optimization of schedule response surfaces is presented and compared with classical optimization techniques using problems of different sizes and complexity. -. The proposed optimization technique was found to be unsuitable for small problems involving less than 10 jobs and 10 machines. For problems larger than this size, the technique was found to stabilize and the number of iterations was reduced, typically, by a third when compared with the best classical optimization technique.

Silicon is conventionally extracted by the carbothermic reduction process, which is energetically very inefficient, besides being harmful to the environment. The proposed Solid Oxide Membrane (SOM) process to manufacture Silicon and other metals is energy-efficient and environmentally friendly. The process and its set-up are similar to those of a conventional Solid Oxide Fuel Cell (SOFC). However, the operating temperature is much higher, and therefore, the Nickel-Zirconia cermet that is used for anode in conventional SOFCs cannot be used in this process. The present work reports the development of a suitable anode cermet coating for the purpose. Based on known physical properties of various materials and the requirements of the application, it was decided to pursue the development of an anode based on Molybdenum-Yttria Stabilized Zirconia (YSZ) cermet. Research was conducted to develop with a process to make a Molybdenum-Yttria Stabilized Zirconia cermet coating that would adhere well to the SOM substrate, which is made from YSZ and would have good electronic conductivity and porosity. The molybdenum oxide and Yttria Stabilized Zirconia mixtures were milled together and slip-cast into pellets. The variation of the cermet characteristics was studied with respect to various milling times and sintering/reduction temperatures. YSZ substrate tubes were dip-coated with slurries of made from milled mixtures of Molybdenum Oxide and Yttria Stabilized Zirconia with methanol. They were sintered and reduced in an atmosphere of Argon with five percent Hydrogen, with the intention of getting Molybdenum-Yttria Stabilized Zirconia cermet coatings. These produced flaky coatings that did not adhere to the substrate. Thus, the experiments with Molybdenum Oxide and Yttria Stabilized Zirconia mixtures demonstrated the difficulty in making the cermets by that technique. Cermet coatings were made using a slurry of Molybdenum metal and Yttria Stabilized Zirconia powder. Molybdenum powder was milled with Yttria Stabilized Zirconia and the resulting powders were made into sluITY with methanol and dip-coated onto the substrate tubes. It was seen in the cermet coatings produced that the electrical conductivity and porosity increased, whereas adherence to the substrate decreased with increasing Mo-content in the cermets. In order to make a cem1et coating that had good electrical conductivity and porosity as well as adherence to the YSZ substrate, a double-layered Molybdenum-YSZ cermet coating was made with a zirconia-rich lower layer and a molybdenum-rich upper layer. This coating had good electrical conductivity and porosity, as well as adherence. This double-layer coating was recommended as the cermet coating for use as the anode for the SOM cell.

This master thesis report contains information about a project carried out at Haldex Brake Products that is situated in Redditch England. The Redditch site is part of the “Commercial Vehicle Systems” division within the Haldex group. Haldex Brake Products is designing and producing electronic anti lock brake systems. The latest product is called GEN2 and the project goal was to increase productivity and achieve more stability within the production processes of this product. The goal was achieved trough implementation suggestions affecting the three categories in overall equipment efficiency (OEE). Nine of the biggest implementations are presented in this report. Some of the suggestions are already implemented and some are under progress to be implemented. These implementations will result in an increase in productivity with additionally 953 products per week. The expected results are based on calculations on an average product. The report also contains suggestions for future actions to even more increase the efficiency of the production processes at Haldex Brake Products in Redditch.

<p>This master thesis report contains information about a project carried out at Haldex Brake Products that is situated in Redditch England. The Redditch site is part of the “Commercial Vehicle Systems” division within the Haldex group. Haldex Brake Products is designing and producing electronic anti lock brake systems. The latest product is called GEN2 and the project goal was to increase productivity and achieve more stability within the production processes of this product. The goal was achieved trough implementation suggestions affecting the three categories in overall equipment efficiency (OEE). Nine of the biggest implementations are presented in this report. Some of the suggestions are already implemented and some are under progress to be implemented. These implementations will result in an increase in productivity with additionally 953 products per week. The expected results are based on calculations on an average product. The report also contains suggestions for future actions to even more increase the efficiency of the production processes at Haldex Brake Products in Redditch.</p>

Low-dimensional semiconductors have been intensely explored as alternative active materials for future generation ultra-scaled smart electronics. However, significant roadblocks (e.g., poor carrier mobilities, instability, and vague potential in scaling-up) exist that prevent the realization of the current state-of-the-art low-dimensional materials’ potential for energy-efficient electronics. We first time developed hydrothermal method to solution-grown two-dimensional Te, which exhibits attractive attributes, e.g., high room-temperature mobility, large on-state current density, air-stability, and tunable material properties through a low-cost, scalable process, to tackle these challenges.

Remanufacturing is an industrial process where used products are restored to useful life. This dissertation describes how products can be designed to facilitate the remanufacturing process. It also describes how the remanufacturing processes can be improved to be more efficient. When comparing remanufacturing with other end-of-life scenarios, it is hard from an environmental perspective to determine which scenario is preferable. This research has shown that remanufacturing is preferable to new manufacturing from a natural resource perspective. With remanufacturing the efforts that initially was used to shape the product part is salvaged. Furthermore, it has been found that it is environmentally and economically beneficial to have products designed for remanufacturing. To avoid obsolescence, the products must be easy to upgrade with new technology in the remanufacturing process. In this dissertation, a generic remanufacturing process is described with all included steps that are needed to restore the products to useful life. In order to make the remanufacturing process more efficient, the products need to be adapted for the process. Therefore, the preferable products properties facilitating each step in the generic remanufacturing process have been identified. A matrix (RemPro) was created to illustrate the relation between each and every generic remanufacturing step and the preferable product properties. Remanufacturing case studies have shown that the companies performing remanufacturing often have problems with material flows, use of space and high inventory levels. This is often due to the uncertainties in the quality and the number of cores (used products) that will arrive at the remanufacturing plants. To overcome these problems, the remanufacturers need to achieve a better control over the product’s design and use phase, i.e. the life cycle phases that precede the remanufacturing process. This control is best performed by the original equipment manufacturers (OEMs). Furthermore, it has been found that Swedish manufacturers often have a weak relation between its environmental management systems and product issues, such as design for environment/remanufacturing. Design for environmental/remanufacturing aspects should be a crucial part of the manufacturers environmental management systems (EMSs) as the products stand for much of the material flows at the manufacturing companies. If the external auditors address the manufacturers to have a life cycle perspective on their business the manufacturer would be more likely to adapt the remanufacturing aspects in their environmental management systems.

<p>För att effektivisera och uppnå de krav som ställs på företaget har Skanskas Sverige AB, i likhet med många andra företag, lagt upp ett kvalitets- och miljöledningssystem som Skanska kallar ”Vårt sätt att arbeta”. Det råder idag osäkerhet om i hur stor utsträckning systemet tillämpas och förenklar arbetet. Samt om det finns en gemensam bild av systemet bland de anställda.</p><p>I denna uppsats kommer endast produktionsförberedelsefasen och produktionsstyrningsfasen behandlas. Uppsatsen består av en kortfattad beskrivning av ”Vårt sätt att arbeta”, byggprocessen och ISO. Den utredande delen av rapporten innehåller data från intervjuer och enkäter.</p><p>Skanska har utvecklat ett mycket bra system för att hjälpa sina anställda i sitt arbete. Utifrån svaren i intervjuerna kan man tydligt se att det finns en gemensam bild av ”Vårt sätt att arbeta” och att det används och uppskattas i stor utsträckning. Men det finns alltid saker som kan förbättrs för att göra systemet ännu mer funktionellt. Det efterfrågas till exempel någon slags uppdelning i systemet.</p>