Showing papers by "Universiti Teknologi Malaysia published in 1996"
Journal Article•
TL;DR: The implementation of an intelligent traffic lights control system using fuzzy logic technology which has the capability of mimicking human intelligence for controlling traffic lights is discussed.
Abstract: Describes the design and implementation of an intelligent traffic lights controller based on fuzzy logic technology. A software has been developed to simulate the situation of an isolated traffic junction based on this technology. It is highly graphical in nature, uses the Windows system and allows simulation of different traffic conditions at the logic controller and a conventional fixed-time controller. Simulation results show that the fuzzy logic controller has better performance and is more cost effective.
130 citations
TL;DR: In this article, a mixed plating rinse wastewater containing zinc, hexavalent chromium, trivalent and cyanide with total dissolved solids of 424 mg/1 was treated by a model consisting of a sand filter and ion exchange columns.
83 citations
TL;DR: Comparisons of various treatment methods to make up the missing records indicate that the most appropriate approach is the modified normal ratio method.
48 citations
TL;DR: In this article, a pure siliceous mesoporous [Si]-MCM-41 has been aluminated using an aqueous solution of sodium aluminate, NaAlO2, to form [Si,Al]-MCMs with the framework Si/Al ratio as low as 1.9.
Abstract: Purely siliceous mesoporous [Si]-MCM-41 has been aluminated using an aqueous solution of sodium aluminate, NaAlO2, to form [Si,Al]-MCM-41 with the framework Si/Al ratio as low as 1.9. 27Al and 29Si magic-angel-spinning (MAS) NMR show that all aluminium is incorporated in the framework. The well resolved X-ray diffraction (XRD) pattern of calcined [Si,Al]-MCM-41 indicates that the mesopore system is stable and that the channel diameter decreases with the increased degree of incorporation of Al. The intensity of lines corresponding to Si(nAl) building blocks in the 29Si MAS NMR spectra reflect changes in the local atomic arrangement upon alumination. Increased reaction temperature at a constant concentration of NaAlO2 enhances the efficiency of the alumination, but increased concentration at constant temperature disrupts the framework structure. Upon treatment with a concentrated (>1 mol 1–1) solution of NaAlO2 at moderate temperatures (100 ± 20 °C), [Si]-MCM-41 is transformed into crystalline zeolite Na-A.
46 citations
TL;DR: In this paper, the feasibility of using complexation and low-pressure RO membranes for the removal of Zn2+ and Cu2+ by applying pressures significantly below 690 kPa was demonstrated.
45 citations
29 citations
TL;DR: In this paper, the authors describe the further development of optical sensor hardware for a process tomography system in which emitters and detectors are used to exploit the optical characteristics of multiphase flow regimes.
Abstract: This paper describes the further development of optical sensor hardware for a process tomography system in which emitters and detectors are used to exploit the optical characteristics of multiphase flow regimes. The optical arrangement is described and the importance of fibre beam position discussed. The proportion of the measurement volume interrogated by the beams is derived. The response of a single fibre is shown followed by a reconstructed concentration profile.
26 citations
TL;DR: In this paper, a complexing eluent containing 20 mM oxalic acid and 20 mM citric acid adjusted to pH 3.6 with lithium hydroxide was used for the separation of heavy metals.
25 citations
01 Jan 1996
TL;DR: In this chapter, several neuro-control techniques with applications to real physical processes are discussed; a water bath temperature control system, an inverted pendulum, an electric vehicle generator Control system, and a multi-input multi-output furnace.
Abstract: In this chapter we discuss several neuro-control techniques with applications to real physical processes; a water bath temperature control system, an inverted pendulum, an electric vehicle generator control system, and a multi-input multi-output furnace. For the water bath and furnace temperature control systems, the emulator and controller neuro-control scheme is applied. However, as these real processes are slow in nature, offline learning methods are used to train the neural networks at first and then on-line learning is applied using the architecture of Fig. 4.2.5 for fine-tuning their performances. In these applications comparison is made with several traditional control methods under varying complexities in the processes. As neuro-control is relatively new it is important to see how well it compares to the more established traditional control approaches.
23 citations
TL;DR: In this article, a CFD software called VORTEX is used as a tool to simulate air flow and thermal comfort in naturally wind ventilated classrooms of an educational institution, which are at different locations, have different configurations and slightly differing outdoor environmental conditions.
18 citations
01 Feb 1996
TL;DR: In this article, numerical approaches based on finite difference (FD) and finite element (FE) techniques for dynamic simulation of single-link flexible manipulator systems are presented and compared.
Abstract: This chapter presents numerical approaches based on finite difference (FD) and finite element (FE) techniques for dynamic simulation of single-link flexible manipulator systems. A finite-dimensional simulation of the flexible manipulator system is developed using an FD discretisation of the dynamic equation of motion of the manipulator. A methodology is then presented for obtaining the dynamic model of a lightweight flexible manipulator using FE/Lagrangian technique. Structural damping, hub inertia and payload are incorporated in the dynamic model, which is then represented in a state-space form. Simulation results characterising the dynamic behaviour of the manipulator are presented and discussed for both FD and FE methods. A comparative study of the FD and the FE methods of dynamic modelling of flexible manipulators on the basis of computational accuracy, efficiency and demand are then considered. The performance of the algorithms is assessed with experimental results in time and frequency domains.
TL;DR: In this article, alkylbenzene homologs from toluene to decylbenzenes have been used as a retention-index scale in reversed-phase high-performance liquid chromatography.
TL;DR: In this article, a RETEC system consisting of a high surface area cell based on a simple theory of electrolysis was used to recover heavy metals from a mixed plating bath in a metal finishing factory.
TL;DR: A new 5-stage explicit fifth order nonlinear Runge-Kutta method is developed based on geometric mean formulation in the functional values which proves advantageous over the usual linear formulation in terms of accuracy.
Abstract: In this paper, a new 5-stage explicit fifth order nonlinear Runge-Kutta method is developed based on geometric mean formulation in the functional values. Since it is impossible to attain a fifth order accuracy with a 5-stage explicit linear method, this strategy of nonlinear formulation proves advantageous over the usual linear formulation in terms of accuracy. The derivation of the method is given in detail along with the absolute stability consideration. A numerical example is provided which shows that this new method is well placed among the fifth order methods and it is superior when compared with fourth order Runge-Kutta method including a 5-stage ones.
TL;DR: In this paper, free-convective flow in the neighbourhood of the upper pole of a heated sphere at high Grashof number is considered and the competing effects of buoyancy and induced pressure gradient are examined to delineate those cases in which a steady-state flow is achieved.
Abstract: Free-convective flow in the neighbourhood of the upper pole of a heated sphere at high Grashof number is considered. Direct buoyancy effects have been studied previously, and it is known that the unsteady boundary-layer solution may terminate in singular behaviour. For a spatially varying surface temperature, a self-induced pressure gradient is present. The effects of this are examined in detail, and it is shown that a singular behaviour may again terminate the solution. The competing effects of buoyancy and induced pressure gradient are examined to delineate those cases in which a steady-state flow is achieved.
01 Dec 1996
TL;DR: In this paper, the performance of a Dynamic Time Slice (DTS) server has been evaluated and the DTS-scheme presented and the bandwidth allocation and three strategies are discussed.
Abstract: In this paper, the performance of a Dynamic Time Slice (DTS) server has been evaluated. Four Asynchronous Transfer Mode (ATM) traffic classes have been defined and the DTS-scheme presented. In addition, the bandwidth allocation and three strategies are discussed. Lastly, some simulation and results are also shown.
18 Mar 1996
TL;DR: In this paper, the authors provide an overview of the development of the privatized power industry in Malaysia and the government efforts to liberalise the electric power sector in order to create an environment of increased competition and efficiency.
Abstract: In the last few decades reliable supply of electric power has become a central issue in the development and economic prosperity of any country. There have been far reaching and radical developments taking place in the electric power industry. Among other developments, privatization trends in power generation are having significant implications on the planning and operation of electric utilities. Over the last few years, Malaysia has experienced a rapid economic growth resulting in an ever increasing demand of electricity. This has prompted the Government of Malaysia to invite private power companies to build, own and operate power generation facilities to meet the growing needs of electric power in the country. This paper provides an overview of the development of the privatized power industry in Malaysia and the government efforts to liberalise the electric power sector in order to create an environment of increased competition and efficiency. The paper presents brief history of the private power generation in the country, and provides the information regarding technical, financial and commercial aspects of the power generation projects constructed in the private sector. Finally, the paper presents a case study on the implementation of a private gas turbine power plant project by Powertek, and various technical and operational issues confronted by the owners of the project.
Proceedings Article•
01 Jan 1996TL;DR: To improve the time-frequency representation of a class of digital modulated signals, a technique for calculating the signal dependent kernel function is derived by minimizing the least-squares error between the calculated and desired time- frequency distributions.
Abstract: One of the features of a radio monitoring system is the estimation of modulation parameters for digital modulated signals. For low signal-to-noise ratio conditions, time-frequency signal analysis is an attractive method to use. However, analysis of digital modulated signals using existing time-frequency distributions have proven that none of these distributions are suitable for this task. To improve the time-frequency representation of a class of digital modulated signals, a technique for calculating the signal dependent kernel function is derived. The kernel function is derived by minimizing the least-squares error between the calculated and desired time-frequency distributions. Simulations using the bilinear formulation of time-frequency distribution verify the results and the desirable time-frequency distribution is obtained for a given signal class.
05 Aug 1996
TL;DR: In this article, two neuro-controllers utilizing the backpropagation algorithm are investigated for robot path tracking performance: inverse neuro-controller and neuro-emulator neurocontroller schemes.
Abstract: In this paper, two neuro-controllers utilizing the backpropagation algorithm are investigated for robot path tracking performance: inverse neuro-controller and neuro-emulator neuro-controller schemes. For a given task of moving a robot from a rest position to a final specified position in a minimum-time, the resulting position and velocity profiles for the investigated neuro-control models showed that, the manipulator could be moved smoothly and accurately. The tracking performance and accuracy are investigated and compared.
TL;DR: Extraction of the stems and leaves of Piper ridleyi with ether afforded N - iso butyl-15-(3′,4′-methylenedioxyphenyl)-2 E,4 E,12 E -pentadecatrienamide (ridleyamide), as well as the known amide, retrofractamide, and sterols was described in this article.
Abstract: Extraction of the stems and leaves of Piper ridleyi with ether afforded N - iso butyl-15-(3′,4′-methylenedioxyphenyl)-2 E ,4 E ,12 E -pentadecatrienamide (ridleyamide), as well as the known amide, retrofractamide, and sterols.
01 Jan 1996
TL;DR: In many real-world applications, there are many nonlinearities, unmodeled dynamics, unmeasurable noise, multiloop, etc., which pose problems to engineers in trying to implement control strategies.
Abstract: In many real-world applications, there are many nonlinearities, unmodeled dynamics, unmeasurable noise, multiloop, etc., which pose problems to engineers in trying to implement control strategies. During the past two decades development of new control strategies has been largely based on modern and classical control theories. Modern control theory such as adaptive and optimal control techniques and classical control theory have been based mainly on linearization of systems [1]–[5].
TL;DR: In this paper, a pure siliceous mesoporous [Si]-MCM-41 has been aluminated using an aqueous solution of sodium aluminate, NaAlO2, to form [Si,Al]-MCMs with the framework Si/Al ratio as low as 1.9.
Abstract: Purely siliceous mesoporous [Si]-MCM-41 has been aluminated using an aqueous solution of sodium aluminate, NaAlO2, to form [Si,Al]-MCM-41 with the framework Si/Al ratio as low as 1.9. 27Al and 29Si magic-angel-spinning (MAS) NMR show that all aluminium is incorporated in the framework. The well resolved X-ray diffraction (XRD) pattern of calcined [Si,Al]-MCM-41 indicates that the mesopore system is stable and that the channel diameter decreases with the increased degree of incorporation of Al. The intensity of lines corresponding to Si(nAl) building blocks in the 29Si MAS NMR spectra reflect changes in the local atomic arrangement upon alumination. Increased reaction temperature at a constant concentration of NaAlO2 enhances the efficiency of the alumination, but increased concentration at constant temperature disrupts the framework structure. Upon treatment with a concentrated (>1 mol 1–1) solution of NaAlO2 at moderate temperatures (100 ± 20 °C), [Si]-MCM-41 is transformed into crystalline zeolite Na-A.
TL;DR: In this paper, a prototype has been developed to help users interact with the Infolan university library system, which adopts a graphical user interface style and incorporates user interface design principles to ensure that the interface is easy to use.
Abstract: This paper discusses the general problems and difficulties in using the Infolan university library. A prototype has been developed to help users interact with the system. The prototype adopts a graphical user interface style and incorporates user interface design principles to ensures that the interface is easy to use. The paper also discusses the user interface and implementation of the prototype.
01 Jan 1996
TL;DR: In this chapter the authors are going to discuss several other methods of control, which include PID (proportional-plus-integral-plus derivative) control, self-tuning control,Self-tuned PID control, generalized predictive control, and also fuzzy logic control.
Abstract: In this chapter we are going to discuss several other methods of control. These methods include PID (proportional-plus-integral-plus derivative) control, self-tuning control, self-tuning PID control, generalized predictive control, and also fuzzy logic control. One of the earliest controllers that were used for control were the PI and PID controllers. PI and PID controllers have been proven to be remarkably effective in regulating a wide range of processes. The use of PI and PID controllers does not require an exact process model and hence, they are effective on industrial processes whose models are considerably difficult to derive. The PI and PID controllers are based on classical control theory and much easier to understand. Field engineers and process operators are able to relate the parameter settings and control system actions.
23 Jun 1996
TL;DR: A new protocol stack for multimedia data communications that consists of the ST-II protocol at the network layer and a modified version of the XTP protocol called XTP-Lite at the transport layer is proposed.
Abstract: We propose a new protocol stack for multimedia data communications. It consists of the ST-II protocol at the network layer and a modified version of the XTP protocol called XTP-Lite at the transport layer. The specific features of the protocol stack are presented and the implementation in a SUN environment is introduced. Related performance measurements are also given to support the conclusions.
01 Jan 1996
TL;DR: In this article, a Dual Boundary Element (DBE) formulation for modeling of crack growth in reinforced concrete is presented, where the influence of reinforcements on the concrete can be considered as a body forces or attachment forces which are confined to a straight line instead of being distributed over the whole domain.
Abstract: The Dual Boundary Element formulation for modelling of crack growth in reinforced concrete is presented. The influence of reinforcements on the concrete can be considered as a body forces or attachment forces which are confined to a straight line instead of being distributed over the whole domain. The solution for these attachment forces is obtained from the condition that the deformations of the concrete and the reinforcement under the action of the external loading are compatible. The fictitious crack model is employed to represent the fracture of concrete in which the fracture zone is replaced by a closing forces acting on both crack surfaces. The numerical results obtained are compared to the FEM analysis and experimental results.