The Effect Of Reparameterisation On The Behaviour Of Nonlinear Estimates

This thesis discussed nonlinear modeling and measures of nonlinear behaviour. A set of data, representing the average weight of dried tobacco leaves (in Several nonlinear models were used to fit the data, however only the Gompertz and the Logistic models were found to be suitable. The estimates of the para meters were calculated by using the Gauss-Newton algorithm in SPLUS Programming Language. A good estimator was the one which had the proper ties closed to the behaviour of a linear estimate . The non linear behaviour of the estimates was assessed using two different approaches , namely the analytical and the empirical approaches . These approaches were employed so that they could complement the existence of any laggings

Advanced Process Control

The debutanizer column is an important unit operation in petroleum refining industries. The top product is liquefied petroleum gas and the bottom product is light naphtha. This system is difficult to handle. This is because due to its non-linear behavior, multivariable interaction and existence of numerous constraints on its manipulated variable. Neural network techniques have been increasingly used for a wide variety of applications. In this book, equation-based multi-input multi-output (MIMO) neural network has been proposed for multivariable control strategy to control the top and bottom temperatures of the column. The manipulated variables for column are reflux and reboiler flow rates, respectively. This neural network model are based on multivariable equation, instead of the normal black box structure. It has the advantage of being robust in nature while being easier to interpret in terms of its input-output variables. It has been employed for set point changes and disturbance changes. The results show that the neural network equation-based model for direct inverse and internal model approach performs better than the conventional proportional, integral and derivative (PID) controller

Distillation Column

Dynamic simulations are used to model systems that are in transition from a steady state to dynamic state. The dynamic model is used to evaluate different basic control schemes and later to evaluate and test the control strategy. In this chapter, a steady-state simulation and dynamic simulation for debutanizer column are performed using a plant process simulator, HYSYS™. The objective of this chapter is to study the process variables of each controller at the column by using different tuning relations and identify the best tuning methods for the controllers in order to optimise the performance of the column. Two tuning methods are used in determining the controller settings for each controller. The process variable for each controller are used by using two different tuning methods are being studied. Furthermore, the effect on the process variables of each controller when using the controller settings based on real plant data and calculated using the PID equation is also being analysed. As for conclusion, the different tuning methods could give the different results on the behaviour of the response for each controller and the optimum response for each controller could be determined by considering the behaviour of the response and the value of integral square of the error (ISE) and integral of absolute value of error (IAE). All the research and findings obtained will be used to improve the overall performance of the plant as well as to improve the quality of the product and maximise profitability. The successful outcome of this chapter will be a great helping hand for industrial application

Conversion of Bio-oil to Biodiesel through Reactive Distillation Approach

Anticipated future energy shortage and environmental concerns have boosted researches on alternatives for renewable resource such as biodiesel. Biodiesel or known as fatty acid methyl ester (FAMEs) is produced from esterification process. This project will focus on esterification process between bio-oil and high boiling alcohol which is n-butanol. This project starts with synthesis of bio-oil based on empty fruit bunches (EFB) bio-oil composition. Then, the esterification process between artificial bio-oil and n-butanol is run and tested for physical properties such as density, viscosity, pH and water content. The product of esterification process is analyzed by gas chromatography to check the actual composition as well as to verify the production of biodiesel. The result shows the existence of butyl ester which is biodiesel in end product. However, the physical properties of the product must be improved in term of acidity, and water content

Penerapan Unsur Sejarah Dalam Pengajaran Dan Pembelajaran Matematik Hasil Penemuan Fibonacci

Tujuan kajian ini adalah untuk membina bahan berdasarkan penerapan unsur sejarah dalam matematik bagi proses pengajaran dan pembelajaran matematik di sekolah menengah serta mengenalpasti pendapat guru matematik sekolah menengah terhadap penerapan unsur sejarah dalam matematik. Kajian ini melibatkan 30 orang guru matematik sekolah menengah di sekitar Skudai, Johor Bahru, Johor. Kajian ini menggunakan instrumen soal selidik dengan nilai kebolehpercayaan adalah sebanyak 0.84. Statistik yang digunakan adalah kekerapan, peratus dan min bagi menilai pendapat guru matematik sekolah menengah terhadap penerapan unsur sejarah dalam matematik. Hasil kajian menunjukkan bahawa semua guru matematik sekolah menengah berpendapat contoh bahan pengajaran matematik yang telah diterapkan dengan unsur sejarah berkaitan hasil penemuan Fibonacci mampu menarik nimat pelajar.Keseluruhan respon guru adalah sederhana mengenai penerapan unsur sejarah dalam matematik meningkatkan kefahaman pelajar tentang konsep matematik, merupakan cara pendekatan yang baik, dan membantu menilai tahap kemampuan pelajar

Solving singular perturbation with one boundary layer problem of second order ODE using the method of matched asymptotic expansion (MMAE) / Firdawati Mohamed and Masnira Ramli

Any physical problems when modeled into equations, may become linear or nonlinear equations with known and unknown boundaries. The exact solution for those equations is not easy to obtain. Hence, an analytical approximation solution in terms of asymptotic expansion is sought. This study seeks to solve a singular perturbation in second order ordinary differential equations. Solutions to several perturbed ordinary differential equations are obtained in terms of asymptotic expansion. The main focus of this study is to find an approximate analytical solution for perturbation problems (linear and nonlinear equations) that occur at one boundary layer using the classical method of matched asymptotic expansion (MMAE). Besides, the underlying concepts and principles of MMAE will also be clarified. Mathematica computer algebra system is used to perform the detail algebraic computations. The results of approximation analytical solution are illustrated by graphs using selected parameters which show the outer, inner and composite solutions separately. Hence, the exact solution and composite solution obtained using MMAE are compared by plotting the graph to show their accuracy. From the comparison, MMAE is one of the best methods to solve singular perturbation problems in second order ordinary differential equation since the results obtained are very close to the exact solution

Engaging And Applying New Communication Technology: A Case Study Of The Usage Of Internet As A Search Practice Among Bernama Journalists

Given the scenario of change within the journalism profession vis-à-vis new communication technology, how does the Malaysian journalism industry cope and adapt to this change? More specifically (i) how do Malaysian journalists find information on the Internet and what are their favourite search engines for information/news gathering? (ii) What are the characteristics of the Internet that influence journalists’ search practices? (iii) What is the attitude of journalists towards Internet usage in their day-to-day work and what are the perceived successes and failures of the Internet as a source of information? (iv) What is the level of knowledge they possess in terms of technology, in general, and the Internet in particular? This article attempts at finding answers to the above questions in an effort to examine the impact of new media, the Internet in particular, from the standpoint of the diffusion of Internet usage among journalists, especially with their preference for search engines, search practices, search tools, websites and web-based technologies

Permasalahan, Sikap dan Keyakinan Guru dalam Pengajaran Bahasa Melayu di Sekolah Rendah di Daerah Kuala Terengganu

Kajian ini bertujuan untuk mengenal pasti permasalahan, sikap dan keyakinan di kalangan guru Bahasa Melayu terhadap pengajaran Bahasa Melayu di sekolah rendah di Daerah Kuala Terengganu Seramai 131 orang guru Bahasa Melayu dipilih secara persampelan kelompok dari 15 buah sekolah rendah di Daerah Kuala Terengganu Data dikumpulkan melalui soal selidik berstruktur dan dianalisis dengan menggunakan statistik diskriptif dan korelasi Pearson untuk mencari hubungan antara pembolehubah masalah, sikap dan keyakinan guru dalam pengaj aran Bahasa Melayu Dapatan kajian yang dijalankan menunjukkan wujud kaitan yang signifikan antara masalah dengan sikap (r = 0 6185, P <05), masalah dengan keyakinan (r = 0.6094, P<05) serta keyakinan dengan sikap (r = 0.9574, P <01) guru dalam pengajaran Bahasa Melayu Tahap masalah guru BM (KB SR) tinggi dan sikap mengajar mereka positif serta keyakinan mereka juga tinggi