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  • Publication
    The Use of Remote Sensing for Estimating the Impact of Climate Change onJapanese Encephalitis Disease Distribution
    (University of the Thai Chamber of Commerce, 2007) ; ;
    University of the Thai Chamber of Commerce. School of Engineering
    In Thailand, Japanese encephalitis (JE) occurs primarily in the north and northeastregions and remains a public health problem because the case fatality rate is 10-50%. Thedisease has recently been recognized in new areas and has recurred in previously endemicareas. The environmental interactions are important in the various effects of temperature andrainfall. To tackle with problems on JE, the development of a model that can predict JE case asa function of these environmental factors is needed. Two models have been developed in thisstudy based on time-series analysis. One is in Chiangrai Province that shows high JE cases inThailand and the other is for the whole country, Thailand. The accuracy (R2) of these modelsare 0.970 and 0.783 respectively in 1992-1993 in which model parameters have beendetermined. The models were applied to 1998 data for validation, which showed the accuracy(R2) of 0.727 and 0.621 respectively. Remote sensing data from NOAA AVHRR is introducedto identify rice fields to make it possible to predict JE cases at near real time at the seasonaltime scale in Thailand. The accuracy (R2) of this model is 0.608 in 1998 between the JE casefrom a model and the actual.
      1  84
  • Publication
    An Empirical Study of Tone Models for Robust Speech Recognition of Isolated Thai Words
    (University of the Thai Chamber of Commerce, 2007) ; ;
    University of the Thai Chamber of Commerce. School of Engineering
    Robust speech recognition system is necessary inreal environment, whereas tone in Thai speech recognitionsystem is an importance as well. Therefore, we attempt to findtone model for enhancing Thai speech recognition system innoisy environment. In this paper we present an empirical studyby configuration fundamental frequency contour, which one ofprosodic information for tone language. Fundamental frequency(F0) and its first order time derivatives (dF0) are composed tothree tone models: F0, dF0, and F0_dF0. They are appended withnon-tonal speech recognition system that used RSF/DRAalgorithm to improve noise robust recognition. We evaluatedtone models using seven words in five different tones with threetypes of noise from NOISEX-92; babble, car, and white noises,resulting in a corpus of 6,370 utterances. Experimental resultsshow that the F0_dF0 model gives significantly improve phonetic,tonal, and word recognition.
      10  60
  • Publication
    Improving the Performance of RPX Using Handoff Detection for Host Mobility
    (University of the Thai Chamber of Commerce, 2006) ;
    University of the Thai Chamber of Commerce. School of Engineering
    As the limited IPv4 address space has made the cellular industry that decided to start using IPv6 for the mobile users in 3G-network.However , there is a potential threat to the success of 3G-network deployment, as the success will depend on the services offering to the end users.These services all reside in the current IPv4 address space,which make them inaccessible to the users that will reside in the IPv6 address space.Previous studies on network address translation have shown that the REBEKAH-IP with Port Extension, RPX is promising in that it provides excellent scalability and also supports all types of services without limitation for the mobile users in cellular network. In this paper, we propose a method that enables to evaluate the performance of RPX scheme in terms of scalability and number of public IPv4 addresses utilization.We provide a mathematical model as a guideline to determine the range of public IPv4 addresses allocated to an RPX gateway in a cellular network.In addition, we present all results on the practical scalability of RPX through the mathematical analysis and simulations.
      6  44
  • Publication
    Using Geographic Information Systems for Fuel Oil Consumption Distribution in Thailand
    (University of the Thai Chamber of Commerce, 2007) ; ; ; ;
    School of Engineering
    ;
    University of the Thai Chamber of Commerce. School of Engineering
    Currently, reports of fuel oil consumption reports are commonly presented in terms of tables andgraphs, that maybe difficult for policy makers to make decision. This study develops the GeographicInformation Systems and Intranet system to demonstrate the fuel oil consumption map for each province inThailand by using ArcGIS 9.0, PHP and MySQL as tools. Moreover, the regression model is developed toforecast fuel oil consumption using SPSS for the statistical analysis. The three- year data in 2000-2003 isused for the data analysis and two-year data in 2004 and 2005 for the model validation. The parameters formodel development are Gross Provincial Product (GPP), provincial population and provincial areas. It canbe concluded that the correlation coefficients of fuel oil consumption related in Gross Provincial Product(GPP), provincial population and provincial areas are 0.98, 0.82 and -0.12, respectively.
      9  87
  • Publication
    University Timetabling Using Evolutionary Computation
    (University of the Thai Chamber of Commerce, 2007) ; ;
    University of the Thai Chamber of Commerce. School of Engineering
    University timetabling problems have been interested by many researchers for more than adecade. However, there is no appropriated solution or computation model available to solve these problemssuccessfully. This is because of many different version of timetabling problems. In this paper, a novalapproach of Genetic Algorithm (GA) for solving educational timetabling problem is proposed, including theconstraints statements, the definition of a hierarchical structure for the fitness function, and the generalizedgenetic operators, which can be applied to matrices representing timetables. The paper focuses on lecturingtimetables only, but not the examinational timetabling. The crossover rate and mutation rate were varied toconduct effective results and they shows that the given appropriate crossover rate of 50% and mutation rateof 50% is the best ratio to solve university timetabling problems.
      5  57