1,197 research outputs found

    Data Normalization in Decision Making Processes

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    With the fast-growing of data-rich systems, dealing with complex decision problems is unavoidable. Normalization is a crucial step in most multi criteria decision making (MCDM) models, to produce comparable and dimensionless data from heterogeneous data. Further, MCDM requires data to be numerical and comparable to be aggregated into a single score per alternative, thus providing their ranking. Several normalization techniques are available, but their performance depends on a number of characteristics of the problem at hand i.e., different normalization techniques may provide different rankings for alternatives. Therefore, it is a challenge to select a suitable normalization technique to represent an appropriate mapping from source data to a common scale. There are some attempts in the literature to address the subject of normalization in MCDM, but there is still a lack of assessment frameworks for evaluating normalization techniques. Hence, the main contribution and objective of this study is to develop an assessment framework for analysing the effects of normalization techniques on ranking of alternatives in MCDM methods and recommend the most appropriate technique for specific decision problems. The proposed assessment framework consists of four steps: (i) determining data types; (ii) chose potential candidate normalization techniques; (iii) analysis and evaluation of techniques; and (iv) selection of the best normalization technique. To validate the efficiency and robustness of the proposed framework, six normalization techniques (Max, Max-Min, Sum, Vector, Logarithmic, and Fuzzification) are selected from linear, semi-linear, and non-linear categories, and tested with four well known MCDM methods (TOPSIS, SAW, AHP, and ELECTRE), from scoring, comparative, and ranking methods. Designing the proposed assessment framework led to a conceptual model allowing an automatic decision-making process, besides recommending the most appropriate normalization technique for MCDM problems. Furthermore, the role of normalization techniques for dynamic multi criteria decision making (DMCDM) in collaborative networks is explored, specifically related to problems of selection of suppliers, business partners, resources, etc. To validate and test the utility and applicability of the assessment framework, a number of case studies are discussed and benchmarking and testimonies from experts are used. Also, an evaluation by the research community of the work developed is presented. The validation process demonstrated that the proposed assessment framework increases the accuracy of results in MCDM decision problems.Com o rápido crescimento dos sistemas ricos em dados, lidar com problemas de decisão complexos é inevitável. A normalização é uma etapa crucial na maioria dos modelos de tomada de decisão multicritério (MCDM), para produzir dados comparáveis e adimensionais a partir de dados heterogéneos, porque os dados precisam ser numéricos e comparáveis para serem agregados em uma única pontuação por alternativa. Como tal, várias técnicas de normalização estão disponíveis, mas o seu desempenho depende de uma série de características do problema em questão, ou seja, diferentes técnicas de normalização podem resultar em diferentes classificações para as alternativas. Portanto, é um desafio selecionar uma técnica de normalização adequada para representar o mapeamento dos dados de origem para uma escala comum. Existem algumas tentativas na literatura de abordar o assunto da normalização, mas ainda há uma falta de estrutura de avaliação para avaliar as técnicas de normalização sobre qual técnica é mais apropriada para os métodos MCDM.Assim, a principal contribuição e objetivo deste estudo são desenvolver uma ferramenta de avaliação para analisar os efeitos das técnicas de normalização na seriação de alternativas em métodos MCDM e recomendar a técnica mais adequada para problemas de decisão específicos. A estrutura de avaliação da ferramenta proposta consiste em quatro etapas: (i) determinar os tipos de dados, (ii) selecionar potenciais técnicas de normalização, (iii) análise e avaliação de técnicas em problemas de MCDM, e (iv) recomendação da melhor técnica para o problema de decisão. Para validar a eficácia e robustez da ferramenta proposta, seis técnicas de normalização (Max, Max-Min, Sum, Vector, Logarithmic e Fuzzification) foram selecionadas - das categorias lineares, semilineares e não lineares- e quatro conhecidos métodos de MCDM foram escolhidos (TOPSIS, SAW, AHP e ELECTRE). O desenho da ferramenta de avaliação proposta levou ao modelo conceptual que forneceu um processo automático de tomada de decisão, além de recomendar a técnica de normalização mais adequada para problemas de decisão. Além disso, é explorado o papel das técnicas de normalização para tomada de decisão multicritério dinâmica (DMCDM) em redes colaborativas, especificamente relacionadas com problemas de seleção de fornecedores, parceiros de negócios, recursos, etc. Para validar e testar a utilidade e aplicabilidade da ferramenta de avaliação, uma série de casos de estudo são discutidos e benchmarking e testemunhos de especialistas são usados. Além disso, uma avaliação do trabalho desenvolvido pela comunidade de investigação também é apresentada. Esta validação demonstrou que a ferramenta proposta aumenta a precisão dos resultados em problemas de decisão multicritério

    Operational auditing within Australian internal audit departments: Developing a framework

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    This thesis identifies factors impacting the effective practice of Operational Audit (OA) in Australia within a holistic framework. Initially, a theoretical framework is developed by reviewing the literature and these framework factors are consequently confirmed or modified based on the results of 28 semi-structured interviews. The result from this thesis therefore is a multi-dimensional framework consisting of three constructs that assist organisations, practitioners and regulators in facilitating/improving their effective practice of OA

    Installation guidance for centerline and edgeline rumble strips in narrow pavements

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    Centerline Rumble strips (CLRS) and Shoulder rumble strips (SRS) and on two-lane rural highways are proven safety countermeasures which provide both an audible and tactile alert to motorists who are about to drift and depart away from their intended lane of travel along two-lane rural highways. Placement of both CLRS and SRS can usually be accommodated within wide pavements (24 ft. or greater paved width) without issue. However, proper placement of one or both is less straightforward for highways with paved widths less than 24 ft. Placement becomes especially difficult as widths approach 20 ft. Other contributing factors such as traffic volume, roadway alignment, and the posted speed limit may suggest the use of one type of rumble strip over another. Many agencies have minimum pavement width dimensions that must be met for rumble strips to be installed along a roadway segment. These minimum widths help to ensure that motorists are able to travel comfortably while limiting the number of times the rumble strips are struck inadvertently. Also on roadways with regular pedestrian and, particularly, bicycle traffic, minimum shoulder widths are generally established to ensure that sufficient space is available for such non-motorized users. Unfortunately, limited guidance currently exists regarding the minimum paved width necessary to install both SRS and CLRS, or which of the two to install when the installation of both is not feasible. The purpose of this study is to provide guidance for installing rumble strips on narrow pavements based on various site-specific factors, such as traffic volume, roadway alignment, and shoulder type. This study involved an analysis of historical crash data for segments with various rumble strip configurations in order to assess the risk of cross-centerline and run-off-road crashes. The crash rates for these configurations were compared to similar control segments without rumble strips while accounting for the effects of other pertinent factors, such as lane and shoulder widths. The research also involved an approximately three months of field studies regarding the road user behaviors to determine how the presence of rumble strips affected the lateral position of vehicles along two-lane highways on the primary (i.e., state-maintained) and secondary (i.e., county-maintained) systems throughout Iowa. Road segments with different cross-sectional characteristics (e.g., lane width, shoulder width) and varying combinations of rumble strip installations (i.e., CLRS only, SRS/ELRS only, or CLRS and SRS/ELRS) were observed. Control segments without rumble strip installations were also observed. Lastly, public input was obtained at 10 Iowa Department of Transportation (DOT) driver’s license stations across the state to gauge public perceptions of rumble strips. This survey sought feedback as to the safety effects of rumble strips as well as secondary effects associated with rumble strip installations, such as noise, effects on passing maneuvers, bicyclist issues, and so forth. These surveys were implemented in Iowa counties with known rumble strip installations to increase the probability that survey participants had experienced previous interactions with rumble strips while driving on the secondary highway system. Based on the results of this research, recommendations and guidance are provided to assist agencies in determining scenarios in which the implementation of rumble strips is warranted. This guidance includes the prioritization of candidate locations based on characteristics such as lane width, shoulder width, and annual average daily traffic. Safety performance functions (SPFs) were developed that can be used to estimate the expected number of cross-centerline and run-off-road crashes for a segment with specific characteristics. These functions provide a means for conducting network screening to identify those locations where centerline and/or shoulder/edgeline rumble strips may provide the greatest benefit

    Information Sharing Along Supply Chain In Malaysian Manufacturing Companies

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    Perkongsian maklumat di antara rakan kongsi rantaian bekalan adalah penubuhan utama untuk mengeratkan koordinasi dan kerjasama dalam meningkatkan pengurusan pelaksanaan rantaian bekalan dan dalam menguruskan aliran maklumat bagi proses rantaian bekalan. Walaubagaimanapun, kebanyakan firma masih enggan untuk berkongsi maklumat dengan rakan kongsi rantaian bekalan. Dengan ini, kajian ini mengkaji kepentingan perkongsian maklumat dalam konteks syarikat pembuatan di Malaysia dan bagaimana perkongsian maklumat dapat meningkatkan prestasi rantaian bekalan. Kajian ini juga menyiasat hubungan antara kualiti maklumat, teknologi maklumat, keselamatan maklumat dan perkongsian maklumat terhadap rantaian bekalan. Di samping itu, ia juga mengkaji bagaimana budaya keselamatan maklumat disederhanakan oleh perhubungan antara keselamatan maklumat dan perkongsian maklumat. Selain itu, kajian ini menyiasat kesan penyerderhanaan teknologi keselamatan maklumat terhadap perhubungan diantara teknologi maklumat dan perkongsian maklumat. Tambahan pula, kajian ini mengkaji bagaimana kebocoran maklumat disederhanakan oleh perhubungan diantara perkongsian maklumat dan prestasi rantaian bekalan. Teori RBV diaplikasikan dalam model kajian bagi menyokong perhubungan diantara kualiti maklumat, teknologi maklumat, dan keselamatan maklumat sebagai sumber untuk bekalan rantaian kepada perkongsian maklumat iaitu keupayaan. Tambahan lagi, RBV menyokong perhubungan diantara perkongsian maklumat sebagai keupayaan kepada prestasi rantaian bekalan sebagai kelebihan daya saing

    Comparison of the effect of pharmacotherapy and neuro-feedback therapy on oral health of children with attention deficit hyperactivity disorder

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    Attention deficit hyperactivity disorder (ADHD) is a chronic and progressive mental disorder related to the childhood period. This study aims to compare the oral health of two groups of ADHD children: those under pharmacotherapy and those under neuro-feedback therapy. 72 ADHD children (aged 6?12) were divided into two 36 member groups: The pharmacotherapy group and the neuro-feedback therapy group. Unstimulated salivary flow (USF), DMFT, and plaque index were assessed in these children. Statistical analysis was carried out on the data with the independent t-test, which was performed using SPSS 16. The significance level of the study was p<0.05. In this study, the USF of ADHD children who used Ritalin was found to be significantly less than that of the neuro-feedback group (1.25 ± 1.21 vs. 1.91 ± 1.16 ml/min; p=0.002). Also, the plaque index (5.9 ± 3.1 vs. 3.94 ± 1.9; p=0.018) and DMFT scores (39% ± 9% vs. 31% ± 9%; p=0.018) were significantly higher for the pharmacotherapy group. Neuro-feedback therapy is preferable to Ritalin treatment for ADHD children in terms of their oral health status

    Surface microstructuring to modify wettability for 3D printing of nano-filled inks

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    This paper investigates the effect of surface wettability on the cross-sectional profiles of printed nanofluid inks which can have a significant role on conductivity of printed lines that are used in the production of printed electronics. Glass substrates were coated with heptadecafluorodecyltrichlorosilane, nonafluorohexyltrimethoxysilane and methyltrimethoxysilane using a dipping method to enhance the wettability of the nanofluid silver ink. Inkjet printing techniques were also applied to develop micro-structural textures on the surface of the glass substrate and thereby modify the wettability of the substrate. The glass substrate, coated with heptadecafluorodecyltrichlorosilane was micro-structured using a UV curable ink to enhance the wettability for the silver nanoparticle ink. Using inkjet printing techniques to micro-structure the substrate allows modification of the wettability of the substrate whilst simultaneously printing on to the substrate. This enables the potential of increasing the performance of such printed lines, essentially permitting additional particulate material to be deposited thus increasing conductivity. The cross-sectional profile of the printed line was predicted numerically and analytically and compared to experimental data where agreement was observed. In addition, three analytical expressions for printed lines on the substrate were developed by writing the force balance equations in the x, y and z directions on a slice of printed line between z and z+dz
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