<p>In this research study, high plastic and medium plastic soils were used in evaluating the physical and mechanical properties of fly ash-soil Geopolymer mixtures. Sieve analysis and Atterberg limit tests were conducted to classify the soil. Class F fly ash, an industrial byproduct, was used in the alkaline environment of a mixture of sodium silicate and various concentration of sodium hydroxide to prepare fly ash based Soil-Geopolymer mixtures. The modified proctor test was conducted to investigate the moisture-density characteristics of mixtures. Based on literature search and preliminary experiments, the experimental design matrix of was developed by using various combination of fly ash content, alkaline ratio, and concentration of sodium hydroxide. Several mixtures based on the experimental design matrix were compacted, cured at elevated temperature and tested for unconfined compressive strength. Regression analysis was conducted to develop regression models to optimize and conduct sensitivity of the compressive strength in relation to mix variables of Soil-Geopolymer mixtures. Based on sensitivity analysis and UCS criteria recommended by DOTD Louisiana, two mixtures were selected for further evaluation along with Standard soil-cement mixtures. The resilience modulus, dynamic modulus, and durability test were conducted for selected Soil-Geopolymer mixtures and standard soil-cement mixtures, as recommended by LA DOTD. The result of the study showed that the alkali activated soil-fly ash mixtures fulfilled the compressive strength criteria of cement treated design (CTD) and cement stabilize design (CSD) of 150 psi and 300 psi, as recommended by LA DOTD. Also, the results indicated that Soil-Geopolymer showed satisfactory performance under compressive strength test and dynamic loading tests. Further, the Soil-Geopolymer mixtures passed wet and dry durability test criteria. Based on mechanical and durability characteristics evaluated it can be recommended that Soil-Geopolymer mixtures studied in this study has an immense potential to be used as pavement subgrade, subbase, and bases.

<p>There can be environmental problems associated with using cement to stabilize soils. Thus, a substitute for cement in the stabilization of road base/subbase is desirable. A Geopolymer can be a good alternative for cement stabilization, as geopolymer produces fewer greenhouse gasses compared to cement. Soil-RAP-Geopolymer as road base and subbase material have been investigated in this research. The standard method of soil stabilization in Louisiana is soil-cement, hence 5% and 10% soil-cement was selected for the comparison. In addition to the physical and mechanical tests, the durability test was also conducted to evaluate the long-term performance of Soil-RAP-Geopolymer mixtures developed in this study. Two different types of soils with medium and high plasticity indices from Louisiana were used. Water content was substituted with alkali at an OMC level to compact the Soil-RAP-Geopolymer at a maximum dry density. An experimental design matrix was established for developing statistical based regression models for the UCS and to optimize the mixture design. Higher FA and RAP content produced mixtures with higher strength, and hence 25% FA and 25% RAP provided the better performance in terms of mechanical properties. Optimum sodium silicate content however depended on the type of soil, and the percentage of FA and RAP in the mixture. UCS, resilient modulus, dynamic modulus and elastic modulus of the optimum mixture were found to be better than 5% and 10% of soil-cement mixtures. The optimum Soil-RAP-Geopolymer mixtures successfully passed the minimum strength criteria of CSD and CTD as used by Louisiana Department of Transportation and Development (DOTD). The durability characteristics also confirmed that the developed Soil-RAP-Geopolymer mixture could be used in the field of soil stabilization. The microstructure and morphology analysis on optimum mixtures confirmed that geopolymer was formed with FA, RAP, and soil in the presence of alkali.

No description available.

The method of understanding and managing diversity within a business is at the heart of the reasoning behind the concept of „supply chain segmentation‟. The overarching principle is to find economic segments within the diverse product and customer mix and to match differentiated strategies accordingly. The aim is to prioritise resource to the products and customers which contribute the highest proportion of sales and to reduce operational costs to those that contribute the lowest proportion of sales, whilst matching service level requirements. In essence this strategy balances supply chain costs for individual products against their value to the business. As a result overall costs are reduced and subsequently profits are increased. This research study pulls together the extensive documentation which is available regarding many supply chain concepts and principles into a single approach. A critical evaluation of the current research is undertaken which concludes that the majority of supply chain segmentation is currently focused within the area of supply chain design and has parallels with the established lean and agile concepts. It is shown that supply chain segmentation can be considered a holistic supply chain strategy and by following a structured framework can be applied to all planning levels, strategic, tactical and operational. The drive of the research was to consider which factors can be used to segment both products and customers. This was tested within an operational environment and it is shown how different strategies can be applied accordingly to each segment. It is proposed by Smith and Slater (2001) that products can be assigned inventory strategies depending on which one of six segments they fall within. The results of a variability index and volume calculations are the determining factors for the segmentation process. It is proposed within this study that an added dimension of lead time variability and a coefficient correlation calculation to determine the level of variability will produce a more accurate inventory model. A segmentation strategy, which combines different supply chain and research methodologies, was applied to a company called Newey and Eyre, which operates within the electrical industry. This is presented within the case study chapter. The practical research programme was designed as three separate research projects and these represent the different planning levels of the business. The first and second research project was carried out within the South West region of the business, where changes were made to the design of the supply chain and to the design and layout of a regional distribution centre (RDC) based at Avonmouth respectively. The third research project is based upon analysis which was undertaken of the company‟s purchasing and inventory system. A discrete event simulation (DES) model of this system was created and this provided the platform to test a number of segmentation strategies against the current system of operation.

Ports compete through providing high quality services at the right price. Ports require reliable performance measurement systems so that their daily operations can be effectively managed, their port assets efficiently utilised, and cargo dwell and standing times minimised. Port performance studies have been approached from strategic, operational, functional, financial and managerial perspectives. Findings in the literature have concluded that the measurement systems currently used are limited because the focus is on measuring efficiency, especially for containerised cargo and terminals. Often, key variables have been ignored and there is focus on improving productivity rather than performance. This research addresses the issue of how current performance measurement systems can be developed to measure the performance of ports more effectively. The research has been designed to contribute to knowledge through conceptualising the needs of developing effective measurement systems in ports by using relevant measures and quantifying those key predictors that influence a port’s performance. Quantitative methods are traditionally used for assessing port performance. This research commences with a discussion of supply chain performance measurement systems in relation to ports. It investigates different supply chain measurement designs, categories and characteristics within each category and examines the effectiveness of the current measurement system applied in Damietta port, Egypt. Findings show that Damietta port currently has no formal measurement system and would benefit from the implementation of a performance measurement system. Data have been collected according to the four types of handled cargoes in Damietta port, namely general cargo, dry bulk, liquid bulk and containers. Data have been collected on a monthly basis. For each type of cargo, data have been edited and keyed and a categorisation scheme has been set up to cover those operations at terminals. The Damietta Port Performance Measurement System (DAPEMS) has been developed using three measures, including: time, revenue and flexibility measures. Initially the system was developed using time measures, where key determinants were discussed and multiple regression analyses applied. Relevant predictor variables were selected and incorporated into the regression models with varying degrees of significance. Following this, DAPEMS has been extended using revenue measures, where revenues resulted from operations time, clearance time and the time a ship stays in a port. The final measure considered was flexibility. This helps to cope with the complexity of operations and uncertainty at ports. DAPEMS has been tested for two months in Damietta Port. In addition, the system’s features, including: reliability, applicability and flexibility have been analysed. The system was tested for two months at Damietta port. The port managers reported the benefits of using DAPEMS as there is no system currently applied in the port. Using additional variables, understanding the relationship between variables, providing information about port revenue and providing managers with estimated future performance were appreciated by the port director and a top manager as this helps them and the port planners in a decision-making process. It is concluded that applying DAPEMS was highly appreciated for providing useful visibility about the port's performance. However, some limitations are addressed and suggestions are proposed to be carried out for future research.

Abstract not available.

Abstract not available.

The thesis explores the significance of occupational identity of, and for, Toronto taxicab drivers during the regulatory regime of the Metropolitan Licensing Commission, 1956-1998. The study uses municipal records, union papers, and local newspapers to identity four critical spheres of contention between the state and the drivers over their occupational identity. The struggle between the regulators and the workers revealed that cultural values such as obedience, honesty, and respectability were inextricably linked to economic values, such as the price of taxi licenses and lease fees. Efforts by the state to control the cultural values linked to the image and identity of taxi drivers profoundly affected material conditions within the industry including the form and structure of taxi companies, the employment relationship between the companies and the workers, and the working conditions of the drivers. Similarly, changes to industry structure, such as the demise of traditional cab companies and the shift to owner-operated vehicles profoundly affected the identity of taxi drivers by altering their status as employees and restricting their ability to access state-legislated protections and benefits including employment standards and collective bargaining. The thesis documents the active resistance of drivers to controls that dictated their attire and the use of meters, their efforts to gain collective bargaining rights as dependent contractors, and their tactics for coping with three decades of unprecedented crime rates. The study examines four critical battlegrounds in the dialectic of taxi driver identity: industry corruption, employment class, rising crime, and continuing education. In doing so, it finds that during the forty-two-year tenure of the Metropolitan Licensing Commission, the link between the identity of taxi drivers and the coveted image of Toronto repeatedly dictated regulatory policy at the expense of the drivers. Toronto taxi drivers were alternately punished for damaging the reputation of "Toronto the Good", saddled with responsibility for creating a "world-class city", and ignored on issues, vital to them, that were not seen as relevant to the municipality's quest for respectability and growth.

The risk analysis process involving information acquisition, modeling, analysis, and decision steps result in system design improvement. To allow an accurate and active system risk assessment in road transportation, this study identifies the contributing factors in reliability of road transportation systems and develops the systematic and stochastic methodologies and mathematical models. The developed models and methodologies aim to assess the reliability and risk of drivers interacting with the today’s typical vehicles equipped with Advanced Drivers Assistance System (ADAS) and Passive Safety Systems (PSS) with any degree of complexity and availability of such systems. The research further examines and addresses the specific needs of such vulnerable users and perhaps risk to others on roads including older drivers, younger drivers and pedestrians. The research presents the conditions monitoring concepts as in-vehicle tools for live assessment of risk state of drivers built on the methodologies and models developed in the studies. The necessity for availability of good data and specific databases for purpose of risk assessment in road transportation is then highlighted and stressed. The complete procedure for accident investigation and data collection is developed and presented in the research and a conceptual model for a typical human centered reliability databases in road transportation is also developed. The research is novel and innovative and expected to pave the way for improvement and development of new risk mitigating systems and better assessment and monitoring of the safety of users on roads and with the capability of information sharing resulting in saving many lives worldwide.

Public investment in transportation forms a large part of the capital budget of many developing countries. In view of the scarcity of development capital, it is essential that the available capital be used to the best advantage. This indicates the need for careful analyses of proposed public investments in transportation. Until quite recently, transportation investment evaluation in underdeveloped countries was almost entirely within the preserve of engineers, with economists taking little active interest in the spatial aspects of economic activity. Economists have recently taken a much more active interest, and new methods of evaluation are constantly being developed and older ones improved. However, there are still some unresolved methodological problems in the evaluation of public transportation investment, and a number of deficiencies in the application of the concepts and methods which have been developed. The objective of this thesis is to describe and evaluate the methods of transportation investment analysis now in use, identify the deficiencies in the existing methods and in their applications, and to propose methods of overcoming the deficiencies. The research which has resulted in this thesis has been in three forms. One was a review of the published literature pertaining to public investment in transportation in underdeveloped countries. The second was in the author's experience in transportation investment analysis in Canada and overseas, for agencies such as the Government of Canada and the World Bank. This experience presented the opportunity of reviewing unpublished writings on the subject, and of reviewing the methodology used and results produced by various consultants and study groups in a wide range of transportation investment analyses in underdeveloped countries. Much of this material, particularly the consultants' reports, is held confidential by the World Bank and by the governments of the countries involved, and therefore cannot be specifically cited in references. The third source of information was in discussions with consultants working in this field, both in Canada and abroad; with representatives of the governments receiving foreign aid for transportation investments, and with the personnel of the World Bank. Chapter I of the thesis is a general introduction to the subject. It deals with the relative importance of transportation investment in underdeveloped countries, and states the objective of the thesis. In Chapter II the objective of public transportation analysis is established, and some of the principles which are basic to all analyses of public investment are considered. In considering the principles, some problems in their applications are identified and the recommended procedures are indicated. All acceptable analyses of public transportation investments must ultimately result in some form of comparison of the costs and benefits of the proposed investment or investments. In Chapter III the methods of measuring costs and benefits are described, and deficiencies in the current methods and their applications are identified. In the cases of relatively minor deficiencies, the correct methods and applications are shown in Chapter III. Possible solutions to the major problems identified are proposed in Chapter IV. The major deficiencies noted in Chapter III are the common failure to relate a proposed transportation investment on an individual link of the system, to the system as a whole, and the failure to relate the transportation system to the economy of the country. These deficiencies will almost invariably result in the incorrect measurement of costs and benefits. In Chapter IV, methods of overcoming these deficiencies are described and evaluated. The most recent published method of conducting a comprehensive analysis which takes account of these factors is the Harvard Model, which consists of two parts: a transportation model and a macro-economic model. The difficulty of applying this approach is considered, and it is concluded that, although the Harvard Model is conceptually the best approach which has thus far been developed, it cannot be applied as a practical method of evaluation at this time. An alternative approach is suggested, based on the methodology used in a recent land transportation study of Dahomey, Africa. The analysis of traffic flows is based on the transportation portion of the Harvard Model, while the economic methodology was developed primarily by the author while engaged in the Dahomey study. The conclusions are presented in Chapter V. It is concluded that transportation investment analyses could be greatly improved, and that most of the necessary improvements are incorporated in the Harvard Model. However, the Harvard Model has not yet been applied successfully, and this will probably be the case for at least the next five to ten years. The methodology used in the Dahomey study is recommended for use as a less sophisticated, but workable alternative, which is also more appropriate to the evaluation of specific investment proposals. / Business, Sauder School of / Graduate