Rolling contact fatigue (RCF) cracks are a widespread problem that impairs the service life of railway rails and wheels, with an associated high cost of labour and capital expenditure for remediation. Severe RCF cracks cause serious safety issues as they can turn down at a larger propagation angle into the rail potentially leading to a rail break. Rail grinding can effectively eliminate RCF cracks if they are detected when they are small enough to be removed. Alternating current field measurement (ACFM) is one of the electromagnetic (EM) techniques that can be used for defect detection and sizing in the rail industry. ACFM has been reported to be more accurate in providing length and depth information than conventional UT for small RCF cracks and is less sensitive to lift-off than eddy current methods. The aim of the present research is to analyse the response of ACFM signals to single and multiple RCF cracks in railway rails using experimental measurements and FE based modelling tools, focusing on the influences of crack vertical angle and multiple cracks (number, spacing, size, uniformity) on the ACFM signal to improve the accuracy of dimension predictions. A novel method (using the Bz signal) is proposed to determine the vertical angle of the RCF cracks, which then allows the crack vertical depth to be determined from the pocket length (standard output from ACFM measurements) and therefore the appropriate amount of rail grinding to remove the RCF cracks. It was found that the vertical angle influences the pocket length determined from the measured ΔBxmax/Bx value when the cracks are shallow (vertical angles < 30°), therefore greater accuracy can be obtained when compensating the ΔBxmax/Bx value using the determined vertical angle. It is shown that the variations of crack surface length, crack inner spacing and crack number for multiple cracks also influence the ΔBxmax/Bx values determined for multiple cracks. The influences of asymmetrical crack shapes on crack sizing are discussed, in general it has been found that for accurate sizing of RCF cracks using a single ACFM scan the cracks should be regular, where the assumption of semi ellipse shapes is appropriate. The methods developed in the project were assessed using calibration samples (machined cracks with different sizes and vertical angles) and rails removed from service containing single and multiple RCF cracks. It was found that the new approach proposed in this work allowed the vertical angle to be predicted well for single and multiple RCF cracks (difference to measurements < 14.3 %). In addition the error in pocket length prediction is greatly decreased when using the sizing method including compensation determined from the crack vertical angle.

Railway tracks deteriorate over time due to the combined effects of train loads and environment. To carry out appropriate maintenance, it is necessary to measure the condition of the track. There are two broad categories of condition measures namely: function and structural measures of conditions. Functional measures of condition assess the condition of the track from the point of view of the user. An example of a commonly used functional measure of condition is track geometry. In the UK, track geometry is measured by the track recording coach and it is carried frequently on the entire network. On the other hand, structural measures of condition assess the structural integrity of the track. Example of a commonly used structural measure of condition is track stiffness. In the UK, track stiffness is measured using the Falling Weight Deflectometer (FWD) and it is carried out less frequently on specific railway track sections as it is very slow, requires closure of the track and is expensive to operate. The aim of this research is to investigate the feasibility of using track geometry measurement to extract track stiffness information and ultimately develop a prototype automated system to achieve this.

The writer analyses the introduction of a simulator enabled approach to railway traction driver training and assesses whether the transition from a conventional training delivery process has been effective. The evaluation of effectiveness is based on a study of Iarnród Éireann’s simulator system. Evidence is contained within four supporting strands, i.e., the change in relevant operational risk that has been calculated using ex ante and ex post runs of Iarnród Éireann’s risk model, the internal rate of return on the financial investment necessary to effect the change, the results of an operator attitudinal study and the findings of an independent expert audit. The study establishes that simulation is an effective training medium. The attributes of the system and the use cases that resulted in this finding are described. The writer also presents additional value-adding training objectives that could increase the project’s internal rate of return or IRR. The study affirms that the required verisimilitude of a simulator system is a function of the training goals and the nature of the skills under development. Design features and use strategies can mitigate for potential negative effects of simulator operation. The findings have industry-wide relevance for those tasked with providing effective training to the 133,000 train drivers within the European Union.

Global warming due to over usage of fossil fuels is leading to different kinds of pollutions. Global warming can be controlled by switching non-renewable fossil fuels with renewable alternative power sources like wind, solar, geothermal, biomass, and ocean. Solar power is the most prominent alternative source around the world. Solar power is being used as alternative power source in almost all countries around the globe. Solar power uses radiation from sun to produce heat and the heat used for different heating and cooling applications whereas electricity being one of them. Solar power is being used in domestic applications as water heaters. A solar collector is used to transfer energy from sun to heat water. A flat plate solar collector is commonly used for water heating systems. Solar radiation is not available entire day as other alternative energy sources so there may be a need to store the collected radiation using a thermal storage system. This study considers a solar collector system with a storage tank and phase change material (PCM). The simulation of a transient process using one-dimensional mathematical model for the collector and storage system with phase change materials (PCMs) is presented. The collector used in this study is a flat plate model and paraffin wax encapsulated in aluminum cylinders as phase change material (PCM). The thermal energy gained by solar radiation can be stored for longer period in a system which has phase change materials (PCMs) due to latent heat storage or enthalpy of fusion.

Improvements in railway capabilities have resulted in heavier axle loads and higher speed operations, which increase the dynamic loads on the track. As a result, railway subsidence has become a threat to good railway performance and safe railway operation. The author of this thesis provides an approach for railway performance assessment through the monitoring and prediction of railway subsidence. The InSAR technique, which is able to monitor railway subsidence over a large area and long time period, was selected for railway subsidence monitoring. Future trends of railway subsidence should also be predicted using subsidence prediction models based on the time series deformation records obtained by InSAR. Three time series prediction models, which are the ARMA model, a neural network model and the grey model, are adopted in this thesis. Two case studies which monitor and predict the subsidence of the HS1 route were carried out to assess the performance of HS1. The case studies demonstrate that except for some areas with potential subsidence, no large scale subsidence has occurred on HS1 and the line is still stable after its 10 years' operation. In addition, the neural network model has the best performance in predicting the subsidence of HS1.

Complex optimisation problems, which are concerned with optimising a given aspect of a complex system, such as time or energy, are difficult to solve. Often a range of solutions exist, and the difficulty lies in determining which solutions to implement in which part of the system. Within this work, a novel method is developed that allows the solver to overcome the key challenges for these types of problems, which are: defining the system parts (subsystems); minimising model complexity; quantifying solution effectiveness; and identifying relationships between solutions and subsystems. The method is demonstrated through application to the problem of railway traction energy saving. Subsystems are defined using quantified network and service characteristics. For each subsystem, the trends between six key solutions and the key performance indicators are analysed using multivariate data analysis and visualisation techniques. The relationships between subsystems are then explored at system level. The analysis determines the suitable solutions for each type of railway, providing information for operators about which solutions to target. Based on the results, the implementation of permanent magnet motor technology is considered, illustrating that the method is a suitable tool for informing further studies.

The profound value of wayside monitoring in helping safeguard the RAMS of railway operations is undeniable. However, despite significant investments by the rail industry, the efficiency and reliability of wayside monitoring have not reached the desired level. Structural deterioration of the rail infrastructure and rolling stock faults still remain a significant problem which needs to be addressed as traffic density, train speeds and axle loads increase in rail networks around the world. The main objectives of this study were to develop and evaluate an advanced wayside monitoring system based on acoustic emission and vibration analysis that can detect various types of axle bearing defects in rolling stock and structural deterioration in cast manganese crossings. The potential architecture for different levels of system correlation has been proposed which can be further integrated with customised monitoring system. A novel signal processing technique based on spectral coherence has been developed. This particular method is based on the identification of suitable templates containing features of interest. It also features in identifying the severity of the defect. In addition, a suitable approach for data fusion from various sensors has been investigated. Successful tests have been carried out under simulated conditions and in the UK network.

Appropriate utilization of the operating room (ORs) requires a balance of many conflicting resources. This cannot be done without an understanding of the role of the OR in the finances of the institution, the missions of the institution, the actual data concerning utilization and costs. Economics of the OR environment have changed dramatically in the past 10 years. For example, technological advances have led to the introduction and advancement of minimally invasive surgical procedures, which are purported to decrease morbidity, reduce hospital length of stay, and improve outcome. However, many of these procedures actually increase OR cost, time and supplies. The increased costs of minimally invasive surgery would not have been a problem in the past, due to the additional costs would have been easily adsorbed because of the large profit margin associated with surgical procedure. Under the implementation of the NHI, the DRG, capitated payment, and global budget, it is not surprising that this area is earmarked by many hospitals as a place to reduce expenses. Therefore, all of us working in the OR must be cost efficient and maximize productivity for long-term success. Accurate estimation of operating times is a prerequisite for the efficient scheduling of the operating suite. In this study, authors sought to compare surgeons¡¦ time estimates for elective cases and to ascertain whether improvements could be made by statistical modeling. The study was conducted in the GYN department at the VGHKS from 2000, Jan. to 2003, June. Author calculates operation time distribution (lognormal) and variance, and operation time finishing probability, costs, and comparing operating time difference between surgeons.

The word ¡§3C products¡¨ means computation, communication and consumer electronics products. Particularly, consumer electronics products become one of the most important part of high technology industry. Recently, the properties of consumer electronics products tend to integrate powerful computation and communication abilities. Further more, the trend of more light, thin, short and small makes every kind of IC inside consumer electronics products highly integration. This tendency describe above brings embedded semiconductor providers a difficult problem. That is, we must improve the computation ability and function integration without increasing area overhead. The proposed method of this thesis is adding computation enhanced instructions in original instruction set without change basic architecture of microprocessor. Further, make a better design choice after analyzing different implement ways and considering their trade off between performance and cost. The goal is producing a powerful microprocessor which is improved the most with the least overhead. There are two directions in the result of this thesis. One is pure enhancing microprocessor computation ability. About 54% special operation execution time is reduced by adding operation enhanced instructions, but only taken 10% area cost. However, if 6.35% system frequency speeddown is acceptable, about 59% special operation execution time could be reduced. The other is the phenomenon after integrating In-Circuit Emulator (ICE) in microprocessor. Apparently, integrating debug mechanism doesn¡¦t change timing of whole system. However, it makes a great deal of circuit area overhead about 112%. This result shows that a system needs keep individual characters between microprocessor and ICE. A batter method of integrating ICE in system is using boundary scan cell in whole system.

Since Taiwan¡¦s building industry started declining in 1994, the government tried several times to save the industry by laws or policies, but the effect was not obvious. There have been hundreds of relative firms closing or downsizing by now. Under this severe recession, how the firms of building industry in Taiwan run business for continuous operation is just the topic of our research. This thesis studies the strategies by theories and industrial-cases collection. After analyzing the building industry in Taiwan (life-cycle, value-chain, and development trend), we develop theoretical strategies for the industry, and then we collect industrial cases to compare. We find that the real strategies of the firms match the theoretical ones we develop very well. Basically, the strategies of the firms of building industry in Taiwan can classify into four types: 1.Market-penetration strategy 2.Product-development strategy 3.Market-development strategy 4.Diversification strategy. Besides, we provide the experience of Tonyan building Ltd. Co.for case study. By studying its target-marketing and win-win system, we share the precious experience with everyone. As a member of Taiwan¡¦s building industry, we hope to contribute ourselves to the continuous survival of Taiwan¡¦s building industry by theory and practical experience.