The forecasted proportions of urban population to total population in Malaysia are steadily increasing from 26% in 1965 to 70% in 2020. Therefore, there is a need to fully appreciate the legacy of the urbanization of Malaysia by providing affordable housing. The main aim of this study is to focus on developing a model to forecast the demand of low cost housing in urban areas. The study is focused on eight states in Peninsular Malaysia, as most of these states are among the areas predicted to have achieved the highest urbanization level in the country. The states are Kedah, Penang, Perlis, Kelantan, Terengganu, Perak, Pahang and Johor. Monthly time-series data for six to eight years of nine indicators including: population growth; birth rate; child mortality rate; unemployment rate; household income rate; inflation rate; GDP; poverty rate and housing stocks have been used to forecast the demand on low cost housing using Artificial Neural Network (ANN) approach. The data is collected from the Department of Malaysian Statistics, the Ministry of Housing and the Housing Department of the State Secretary. The Principal Component Analysis (PCA) method has been adopted to analyze the data using SPSS 18.0 package. The performance of the Neural Network is evaluated using R squared (R2) and the accuracy of the model is measured using the Mean Absolute Percentage Error (MAPE). Lastly, a user friendly interface is developed using Visual Basic. From the results, it was found that the best Neural Network to forecast the demand on low cost housing in Kedah is 2-16-1, Pahang 2-15-1, Kelantan 2-25-1, Terengganu 2-30-1, Perlis 3-5-1, Pulau Pinang 3-7-1, Johor 3-38-1 and Perak 3-24-1. In conclusion, the evaluation performance of the model through the MAPE value shows that the NN model can forecast the low-cost housing demand very good in Pulau Pinang, Johor, Pahang and Kelantan, where else good in Kedah and Terengganu while in Perlis and Perak it is not accurate due to the lack of data. The study has successfully developed a user friendly interface to retrieve and view all the data easily.

Introduction The established methods for the production of 99Mo, based on fission in nuclear reactors, continue to present problems as a result of the plant’s aging and the significant investments needed for maintenance or for their renewal. Much research work is thus in progress on the study of alternative methods for the production of 99mTc in quantities and with the degree of purity required for the clinical use. Between them, the cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction has turned out as the most attractive alternative. One critical aspect regarding the production of 99mTc with cyclotron is the need for a robust and reliable target production process. Several techniques have been indicated as extremely promising such has plasma spray and laser cladding; however these methods require specialized instrumentation and complex operations to be performed handling activated materials in order to recover irradiated Mo. In this work we report the development of the work done at the University of Bologna, as a part of a wider INFN project, as regards the methods of preparation of solid targets suitable for the production of 99mTc irradiating a target of 100Mo, employing a cyclotron for biomedical use, normally operated for the production of PET radionuclides. Material and Methods Irradiations were performed with a 16.5 MeV GE PETtrace cyclotron equipped with a solid target station previously developed by our group (1). In initial tests, a stack of 1–3 metallic foils, 100 μm thick, of natMo were irradiated with protons in the 15.9→9.8 MeV energy range. Foils were then dissolved in a HNO3-HCl solution and samples were analyzed with high resolution gamma-ray spectrometry (Canberra, including a HPGe detector with a 30% relative efficiency and a resolution of 1.8 keV at 1332 keV) using Genie2000 software; the measurement campaign lasted several weeks to take into account the different half-lives of the produced radionuclides. Results were extrapolated to a highly enriched 100Mo target and compared to Monte Carlo simulations previously performed with FLUKA and TALYS codes (2). In order to investigate a method of preparation of the target that would make easier the recovery of the enriched material and recycling for the preparation of a new target, it was subsequently studied the preparation of pellets of Molybdenum trioxide. MoO3 powder (Sigma Aldrich, 99.9% trace metals basis, particle size < 150 μm) was used to prepare pellets using a 10 ton press. Pellets obtained in this way were then sintered on a Platinum support using a CARBOLITE furnace under a controlled atmosphere; the temperature was ramped according to a controlled and reproducible temperature cycle. Sintered pellets were subjected to visual inspection, mechanical tests of resistance to loading and downloading in the cyclotron target station, thermal tests and then irradiated at increasing current. The irradiated targets were again visually inspected then weighed, dissolved and subjected to gamma-ray spectrometry analysis. Results and Conclusion The experimental saturation yield for 99mTc calculated on the basis of the gamma-ray analysis of irradiated metal foils, gave an extrapolated yield of 1.115 ± 0.015 GBq/μA for a 100 μm thick 100Mo enriched target, in accordance with the value of 1.107 ± 0.002 GBq/μA obtained in Monte Carlo simulations. On these bases, an irradiation of 3 h at 50 μA is expected to produce 16.3 ± 0.2 GBq of 99mTc; considering the use of an efficient purification system, a radionuclidic purity > 99.9 % 2 h after the EndOfBombardment and a specific activity comparable with the actual standards are expected as achievable. Experiments on sintering pellets are still on going at the time of writing this report; initial results showed that addition of proper aggregating materials allows for suitable pellets preparation. The sintering process allows to obtain pellets having sufficient mechanical strength to withstand loading and downloading operations. Initial irradiation tests with beam current up to 25 μA were performed successfully with no changes in mass and mechanical properties of the pellet. These encouraging results suggest that sintered pellets may be a relatively inexpensive and easy solution to prepare 100Mo targets for the cyclotron production of 99mTc. Further experimental tests at higher beam current will be performed in order to assess the maximum current achievable with no damage of the target. At the same time, a prototype automated module based on standard industrial components is in testing phase as regards performance in the separation and purification processes.

Tuberculosis is a major concern in low- and middle-income countries, but may be diagnosed using standard chest x-rays. Conventional film-screen x-ray detectors require more maintenance than digital x-ray detectors and need a good supply chain of developer chemicals and film, which make them difficult to maintain in low-infrastructure areas of the world. Current digital x-ray technology is prohibitively expensive for this market, although it brings the possibility of tele-radiology and tele-medicine, quicker diagnosis time, and virtually no cost per test compared to other diagnostics for tuberculosis. This thesis examines the requirements on a small-sized, low-cost digital x-ray detector for this application. Two small x-ray detectors were integrated into x-ray systems, then characterized for detector performance using metrics known as modulation transfer function, noise power spectrum, and detective quantum efficiency. The system designs and the results of the experiments are shown. Details are also shown about the setup of the x-ray lab, including the door interlock system for a lead-lined x-ray cabinet. To determine whether a smaller x-ray detector is diagnostically accurate enough for tuberculosis diagnosis compared to full-size chest radiography equipment, a medical study was designed and run using a web-based survey of radiologists in Pakistan, where tuberculosis is a recognized disease. In an attempt to compare x-ray detector performance, MATLAB code was written to measure the modulation transfer function, noise power spectrum, and detective quantum efficiency of x-ray systems. The details about this code, and challenges in simulating the performance of physically different detectors are explained in the thesis.

Usability testing is a branch of usability engineering that focuses on analyzing and improving user interactions with computer systems. This testing technique has been used in different industries for years and has proven to be very useful in determining major issues with applications before they are released, however the use of this technique has been slow to gain widespread acceptance in testing health information systems. This study was designed to determine if a specific form of usability testing, Low-Cost Rapid Usability Testing, can be introduced as a standard part of the system development lifecycle (SDLC) for health information systems in a cost effective manner. To determine if this was possible a full cost-benefit analysis of Low-Cost Rapid Usability Testing was performed on a health information system, the BC Chronic Disease Management (CDM) Toolkit, tracking all of the costs involved in the testing process and comparing them against the possible costs that may have been incurred if this testing was not performed. It was found that by introducing this technique into the system development lifecycle to allow for earlier detection of errors in a health information system it is possible to achieve an estimated 36.5% to 78.5% cost saving compared to the impact of errors going undetected and causing a technology-induced error. Overall it was found that Low-Cost Rapid Usability Testing can be implemented in conjunction with other testing techniques in a cost effective manner to develop health information systems, and computer systems in general, which will have a lower incidence of technology-induced errors. / Graduate

Seven above-knee amputees were fitted with a low-cost prosthetic knee and different low-cost swing-phase setups were clinically assessed. Clinical testing included the 20-meter walk tests utilizing a mobile computer setup connected to a potentiometer and accelerometer mounted on the prosthetic limb. As hypothesized, incorporating friction and a spring system resulted in improved gait function. Of the two spring systems evaluated, the dual spring system performed better than the single spring system resulting in increased walking velocity with decreased maximum flexion and terminal impact. The dual spring system resulted in lower terminal impact because the deactivation of the stiff spring and activation of the less stiff spring during the last 25 degrees of swing-phase before extension allows the shank to decelerate and hit the bumper at a lower velocity. The swing-phase control mechanisms evaluated have the potential to improve prosthetic function and are ideal for use in low-cost and peadiatric prostheses.

Seven above-knee amputees were fitted with a low-cost prosthetic knee and different low-cost swing-phase setups were clinically assessed. Clinical testing included the 20-meter walk tests utilizing a mobile computer setup connected to a potentiometer and accelerometer mounted on the prosthetic limb. As hypothesized, incorporating friction and a spring system resulted in improved gait function. Of the two spring systems evaluated, the dual spring system performed better than the single spring system resulting in increased walking velocity with decreased maximum flexion and terminal impact. The dual spring system resulted in lower terminal impact because the deactivation of the stiff spring and activation of the less stiff spring during the last 25 degrees of swing-phase before extension allows the shank to decelerate and hit the bumper at a lower velocity. The swing-phase control mechanisms evaluated have the potential to improve prosthetic function and are ideal for use in low-cost and peadiatric prostheses.

Precisely measuring the flow rate in sprayers is a key technology to precision agriculture. With the development of advanced technologies, the demand for the ability to measure flow rate of individual nozzle has become more important and urgent. This paper investigates the possibility of developing a low-cost flow rate measurement technique. The technique is based on analyzing the acoustic signal from a microphone placed near the nozzle tip. A comparison between acoustic signal and vibration signal was made to study the relations between them. Then several possible locations of the microphone for measuring flow rate were tested and compared, and one has been chosen as the best location. After that, two methods of analyzing data were proposed, one that could better describe the original curve was chosen. With all of that work done, further experiments were conducted on a variety of nozzle tips. The results showed that an acoustic sensor could be used as an indicator of flow rate from a nozzle, but that unique calibrations for different nozzle tips would be necessary.

abstract: In 2004 the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, and Slovenia joined the European Union (EU) as part of the EU's greatest enlargement to date. These countries were followed by Bulgaria and Romania in 2007. One benefit of joining the EU was the freedom for residents in the new EU member states to migrate to western European nations, notably the United Kingdom (UK). A result of this new freedom was an increased need for air travel. The intersection of the expansion of the EU with the introduction of low-cost airline service was the topic addressed in this study. Yearly traffic statistics obtained from the UK Civil Aviation Authority were used to formulate a trend line of passenger volume growth from 1990 to 2003. Through a time series regression analysis, a confidence interval was calculated that established that, beginning with the year 2004, passenger volumes exceeded the probable margin of error, despite flat population growth. Low-cost carriers responded to these market conditions through the introduction of new flights across the region. These carriers modeled themselves after Southwest Airlines, a strategy that appeared to be more effective at meeting the needs of the post-accession travel boom. The result was a dramatic rise in both passenger volumes and low-cost airline routes in an east-west direction across the continent. / Dissertation/Thesis / M.S.Tech Technology 2012

Cu(In,Ga)(Se,S)2 (CIGS) solar cells have attracted a lot of attention due to their high performance and the prospect for lower manufacturing costs over conventional crystalline silicon solar cells. All recent record efficiency CIGS absorbers have been deposited using vacuum processing which introduces high manufacturing costs. CIGS can also be compatible with low cost, atmospheric processing which can significantly reduce manufacturing costs. Recently, there has been some progress in developing atmospheric solution-based processes for CIGS. Among different solution approaches, deposition of molecular precursors can be advantageous in terms of simplicity and straightforward compositional control. Nonetheless, the developed methodologies involve highly toxic reagents or large impurity content in the device, limiting the potential for commercialisation. This thesis describes the development of a novel solution-based approach for the deposition of CIGS absorber layers. Metal chalcogenides are used as the starting precursors, which are free from detrimental impurities. These compounds contain strong covalent bonds and, consequently, they are insoluble in common solvents. Until recently, hydrazine, which is highly toxic and explosive, was the only solvent to effectively dissolve these types of precursors, limiting the feasibility of this approach for industrial applications. In this work, metal chalcogenides are dissolved in a safer solvent combination of 1,2-ethanedithiol and 1,2-ethylenediamine, completely eliminating hydrazine from the process. By using this solvent system, optically transparent solutions are formed which exhibit long-term stability. The precursor solutions are decomposed cleanly and they are converted to single phase CIGS upon selenisation. CuIn(S,Se)2 solar cells with power conversion efficiencies up to 8.0% were successfully fabricated by spray depositing the precursor solution, followed by a selenisation step. This progress has been made by continuously optimising the deposition, drying, and especially the selenisation configuration. Among other parameters, the working pressure during selenisation was found to have a dramatic effect on the material crystalline quality. Rapid thermal processing was also explored as an alternative selenisation configuration to tube furnace annealing and it was shown to improve the back contact/absorber interface. It has been demonstrated that Ga can easily be incorporated in the absorber for band-gap tuning and, consequently, for VOC enhancement of the solar cells. The structural properties of the films were investigated with Ga content, as well as the opto-electronic characteristics of the corresponding solar cells. The band-gap of the material was conveniently varied by simply adjusting the precursor ratio, allowing for fine compositional control. By using this technique, Cu(In,Ga)(Se,S)2 solar cells with conversion efficiencies of up to 9.8% were obtained. The solar cell performance in this work is limited by the porosity of the absorber and the back contact quality. Despite a significant improvement during the course of this work, the remaining porosity of the absorber causes selenium to diffuse towards the back forming a thick MoSe2 layer and causing a high series resistance in the device. A low cost, solution-based technique was also developed for the deposition of aluminium-doped zinc oxide films that can be used as the transparent conductive oxide layer in thin film solar cells. This methodology involves the use of an ultrasonic spray pyrolysis system, which is a very versatile and easily controlled deposition technique. Although the presence of oxygen makes the film closer to stoichiometric (fewer oxygen vacancies) good electronic and optical properties have been obtained by process optimisation. Films deposited with optimum conditions exhibited a sheet resistance of 23 Ω/sq, which can be further reduced by increasing the thickness with minimal transmittance losses. The simplicity, low toxicity and straightforward control make the proposed methodologies extremely potential for low cost and scalable deposition of thin film solar cells.

Submitted by Roger Oliva Felix (roger.oliva.felix@hotmail.com) on 2018-08-17T18:58:00Z No. of bitstreams: 1 felix_dissertation.pdf: 7309569 bytes, checksum: 90790c5622c5031e74dcc461ccefb15b (MD5) / Rejected by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: 1 - Inserir no corpo do texto a ata de aprovação, pois é um item obrigatório. Agradecemos a compreensão. on 2018-08-21T12:19:26Z (GMT) / Submitted by Roger Oliva Felix (roger.oliva.felix@hotmail.com) on 2018-08-21T12:44:28Z No. of bitstreams: 1 felix_dissertation.pdf: 7309569 bytes, checksum: 90790c5622c5031e74dcc461ccefb15b (MD5) / Approved for entry into archive by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br) on 2018-08-21T12:57:04Z (GMT) No. of bitstreams: 1 felix_ro_me_bauru.pdf: 7133378 bytes, checksum: 7876ad942a5467301d81cd82ddae630d (MD5) / Made available in DSpace on 2018-08-21T12:57:04Z (GMT). No. of bitstreams: 1 felix_ro_me_bauru.pdf: 7133378 bytes, checksum: 7876ad942a5467301d81cd82ddae630d (MD5) Previous issue date: 2018-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho aborda o estudo experimental das características não lineares de atrito interno em atuadores pneumáticos. Os atuadores pneumáticos contêm uma tecnologia limpa comparados com os atuadores hidráulicos, ótima relação entre potência e massa suportada, e baixo custo em relação a atuadores elétricos. Também possuem internamente características não lineares que influenciam no controle de um servoposicionador, incluindo principalmente a vedação do êmbolo com o perfil do atuador e a vedação da haste. Portanto, para obter a precisão de posicionamento é necessária uma caracterização do atrito interno. Os métodos utilizados para o desenvolvimento da pesquisa são: investigação do problema de atrito com o modelo LuGre; desenvolvimento do equipamento experimental com um controlador de baixo custo Raspberry Pi; e realização dos experimentos com a identificação automática de atrito em atuadores pneumáticos. Obtendo assim, a visualização gráfica da força de atrito em função da velocidade em regime permanente. A força de atrito em relação aos parâmetros do modelo é calculada em tempo real, possibilitando, dessa forma, a visualização do comportamento da força ao longo do deslocamento do êmbolo do atuador. Os resultados têm a finalidade de verificar as características de atrito do atuador pneumático através dos parâmetros identificados. Desse modo, é possível classificar o atuador pneumático mais adequado para aplicação em sistemas de posicionamento e monitorar o seu desgaste. / This work presents an experimental procedure for determination of the nonlinear characteristics of internal friction of pneumatic actuators. Pneumatic actuators are a clean technology compared to hydraulic actuators, have good relationship between power and supported mass, and low cost compared to electric actuators. They also have nonlinear characteristics which influence the control of the servo positioner, including mainly the piston seal with the intern surface of the pneumatic actuators and rod seal, therefore to get the positioning accuracy it is necessary a good characterization of internal friction. The methods used for the development of the research are: investigation of the friction problem with the LuGre model; development of experimental equipment with a low cost controller Raspberry Pi; and achievement of the experiments with the automatic identification of friction in pneumatic actuators. Thus, it is obtained the graphical visualization of the friction force as a function of the velocity in steady state. The friction force in relation to model parameters is calculated in real time, enabling the visualization of behaviour of pneumatic force along of displacement piston of the actuator. The results have as purpose verify the friction characteristics of the pneumatic actuator using the identified parameters, thus, it is possible to classify the best pneumatic actuator for application in positioning systems and to monitor the your wear.