ERU - 2008

Permanent URI for this collectionhttp://192.248.9.226/handle/123/14685

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item: Conference-Abstract
A compact and high performance SC DC/DC buck converter
(2008) Baek, CJ; Kumarawadu, S
A novel paralleling interleaved discharging (PID) approach is presented to reduce the output ripple and continuous input current waveform in step-down switched capacitor (SC). Theoretical analysis and the computer simulation show that PID method can reduce output ripple by a factor of three and improve output power level by 8. 7%. The PID method can provide a large range of constant desired values of the output voltage for a given input voltage by paralleling.
item: Conference-Abstract
A comparative study on work related attitudes of operator level employees and supervisors across firms of different ownership in Sri Lanka
(2008) Wanniarachchi, T; Wickramasinghe, V; Wanigatunge, N
This study investigates the influences of work related attitudes different ownerships (local, foreign and joint venture) type of firms as well as different employee category (worker level employee and supervisory level employee) in Sri Lankan context. An examination of samples of 200 machine operators and 100 supervisory level employees revealed that there was no significant difference between job satisfaction and organizational commitment of different ownership companies.
item: Conference-Abstract
A novel active inrush suppression method for SC converter
(2008) Baek, CJ; Kumarawadu, S
A new type of Inrush suppression circuit in SC buck converter is proposed. The method is realized by the hybrid of passive and active circuits. It adapts PIC micro controller to generate multi pulse to drive multi switches. Computer simulation shows that this method suppresses inrush current drastically.
item: Conference-Abstract
A novel morphin-based obstacle avoidance control algorithm for USVs
(2008) Jayendra, G; Kumarawadu, S; Piyasinghe, L
This is an effort of employing good obstacle avoidance algorithms for unmanned surface vehicles (USV) which are already developed for unmanned ground vehicles (UGV). Previously developed Morphin algorithm is utilized for the obstacle avoidance ofUGV. Simulations were carried out using MatLab to prove the validity of the algorithms. Approach towards the results and results are presented. Other USV developers can employ these algorithms for their developments.
item: Conference-Extended-Abstract
A study of information literacy skills of engineering undergraduates at University of Moratuwa
(2008) Seneviratne, TM; Wickramasinghe, V
This research was conducted to investigate the status of information literacy skills of the undergraduates of Engineering Faculty of University of Moratuwa. Survey questionnaire was the main method of data collection and it was administered to stratified random sample of 189 Level 4 Engineering undergraduates representing all academic departments. The findings and implications of the research will be discussed.
item: Conference-Abstract
Accurate attitude estimation of low-accelerating vehicles by the use of multiple low cost MEMS-Based IMUs
(2008) Dharmapriya, TDK; Kumarawadu, S; Piyasinghe, LP
Inertial sensors and inertial measurement units (IMUs) are widely used in navigation support systems, autonomous vehicle navigation, and vehicle motion control process. Inertial measurement based attitude determination and navigation systems are capable of sustaining their accurate operation with high resolution without subjecting to external jamming and noise conditions. The most vital equipment in inertial measurement system is the IMU. The required degree of accuracy, resolution and repeatability in angular velocities and accelerations mainly depend on the implementation technology of the gyroscopes and accelerometers. The paper presents a methodical approach to obtain better attitude determination for vehicles with low-cost, multiple MEMS-based IMU. The simulated results are based on the mathematical models of MEMS-based gyroscopes and accelerometers.
item: Conference-Abstract
Alternative techniques for economical and quality injection mould making for low volume production in Sri Lanka
(2008) Mangala, KHJ; Walpolage, S; Warnakulasuriya, N; Wickramasekara, H; Wijayawardana, L
At present, low volume production of injection moulded parts are being neglected due to high costs. This research was carried out to identify feasible alternative techniques of injection mould making for low volumes. A quantitative analysis was carried out with respect to quality and cost on these methods in Sri Lankan context. Further analysis revealed that reusable mould base method, based on the interchangeability of components is the most feasible method of production, which reduces costs by 30% to 70%.. This was illustrated by a case study and a detailed design.
item: Conference-Abstract
Alum and Lime dosing controllers for water treatment plant
(2008) Hettiarachchi, LP; Dassanayake, VPC
Many techniques are applied to control coagulant dosing in a drinking water treatment plant. Coagulant dosing rate is non linear correlated to raw water parameters such as turbidity, conductivity, pH, temperature, etc. Manual method called Jar testing is used to decide the dosing rates of Alum and Lime. Since parameters of the water source are continuously changing, dosing rate of Alum and Lime are difficult to adjust manually. The aim of the research is to automate the system by obtaining a simple relationship to find optimum coagulant dosage and handle practical situations of water treatment plants.
item: Conference-Abstract
An Active monocular platform for intelligent vehicles: Design and simulations
(2008) Piyasinghe, LP; Kumarawadu, S; Jayendra, G; Dharmapriya, K
Intelligent vehicles have to perceive their environment in order to navigate and avoid collision. This capability is also important in other applications such as mobile robot navigation, Automated Guided Vehicles (AGVs) for automated material handling, intelligent transportation systems, rescue operations in natural disasters, and wildlife observation. Since angular rotations of the moving vehicle deteriorate the quality of the image, cameras have to be mounted on a stabilized platform. Further control is required if the cameras are expected to keep looking at an object of interest irrespective of the vehicle's translational motion. This paper describes designing a monocular vision, system kinematics, and dynamics analysis. Simulation results are also presente
item: Conference-Abstract
An analysis of environmental performance of natural dyes
(2008) Wijayapala, UGS
The objective of this study is to demonstrate the limited heavy metal content in natural dyes (ie to demonstrate near zero burden on the environment) and the final effluent COD (to test the hypothesis that the effluent is less problematic and therefore easy to treat). For the selected material both hypotheses have been demonstrated. Characterisation of eco -friendliness of natural dyes reveals that no major harm is caused to the environment when compared with the synthetic dyes.
item: Conference-Extended-Abstract
Analysis and design of garbage compacting tractor trailer for Sri Lanka
(2008) Wanigasinghe, N; Wijesinghe, A; Fernando, MARV; Piyasiri, TA
Low efficiency in collection and transportation of garbage and environmental pollution with the currently available vehicles such as open dump trucks, tractor trailers are two of the main problems encountered in solid waste management in Sri Lanka. This paper proposes an innovative design using a currently available tractor trailer improve above problems. The capacity of waste transported is improved by compacting the garbage using a hydraulic system. A closed body is built with safe unloading system to overcome the environmental pollution.
item: Conference-Abstract
Analysis of risks and bottlenecks of a poly bag manufacturing factory - a case study
(2008) Gopura, RARC; Jayawardene, TSS
The material prices of poly bags skyrocket to new heights and forecasters see no end to this trend. Also legal restrictions are imposed on some types of polythene products. In this situation, any entrepreneur engaging in the poly bag manufacturing process faces significant challenges. Therefore, a case study of an analysis of risks and bottlenecks of a poly bag manufacturing factory was carried out for the purpose of modeling and simulation of a poly bag manufacturing factory to improve the productivity to face the underlying challenges. This paper presents the analysis methods, and the results of the analysis are also discussed.
item: Conference-Abstract
Biodiesel production from high FFA Rubber Seed oil
(2008) Sampath, PRAU; Samarakoon, SPAGL; Ismail, FM; Gunawardena, SHP
Sri Lanka should look at alternative fuel sources to reduce its dependence on foreign oils. Diesel is the highest used petroleum product in the transport sector. Biodiesel extracted from non edible oils like Rubber Seed Oil (RSO) is one such alternative fuel that is feasible in Sri Lanka. However RSO contains high amount of free fatty acid (FF A). This lowers the yield of methyl ester (biodiesel) formation if alkaline esterification is performed directly. Therefore a two-step trans-esterification process is used to convert high FFA non-edible oils to_biodiesel. First step is acid easterification to reduce the FFA of oil and the second step is alkaline esterification to produce bio diesel from oil with FFA reduced. ln this study two of the major factors that affect the efficiency of the acid esterification step were investigated. The properties of biodiesel produced with standard biodiesel and petroleum diesel fuel were also compared.
item: Conference-Abstract
Car park navigating system
(2008) Dias, SAD; Abeywickrama, RV; Attanayake, AATI; De Silva, GRH; Domingo, DDAPC
It is known that every working day millions of drivers are looking for a place to park and most of the urban traffic occur due to the drivers loitering in search of parking spaces. We wished to offer a simple solution to this problem by implementing a car park navigating system using ultrasonic sensors. RS-485 protocol, a mobile application and Bluetooth communication. The system indicates whether the car park is full or not and provide a simple navigation to the driver to the vacant spot.
item: Conference-Abstract
Coir pith activated carbon for the removal of dyes from aqueous solutions
(2008) Dhanusekera, DW; Amarasinghe, BMWPK
Adsorption of methylene blue, malachite green and nylosan blue dyes onto carbonized coir pith from aqueous solutions was studied. Adsorbent was prepared by carbonizing coir pith at 700 C for l hr. Batch experiments showed that solution pH and adsorbent dose affects the adsorption capacity. The adsorption capacity was highest at solution pH 2 for nylosan blue and above pH 5 for methylene blue and malachite green. The kinetic data fits to second order model. The equilibrium data were satisfactorily fitted to Freundlich isotherm.
item: Conference-Abstract
Construction and demolition waste as a road construction material for flexible pavements
(2008) Jayasooriya, VWP; Kumara, MAW
This research is focuses on evaluating the physical properties and durability characteristics of both demolition and process waste for flexible pavement construction. The initial results showed that there is a possibility to replace aggregate base course using crushed concrete material of demolition waste Possibility to replace soil using construction and demolition waste as a stabilization agent are to be studied. This study included extensive laboratory and field testing. California bearing ratio (CBR), moisture susceptibility and abrasion evaluations tests are conducted. Effects of repeated load over the constructed pavement are evaluated using Nondestructive testing (falling weight deflectometer) on accelerated pavement testing facility.
item: Conference-Abstract
Correlation between ultrasonic attenuation and hardness of tool steels
(2008) Dayananda, HGSM; Munasinghe, RGNDS; Sivahar, V
Theory of propagation and reflection of ultrasonic waves in metals in used to locate the internal defects of engineering components. It is observed that the energy absorption of ultrasonic waves (attenuation) in a metal depends on the physical and mechanical properties of metals. In this work efforts are made to find the correlation between attenuation and hardness of metals using ultrasonic waves. Commercially available Ultrasonic Flaw Detector bas been used to measure the attenuation of the ultrasonic waves of tool steel (DF2) which has been beat treated to change its hardness. The experimental curve is compared with theoretical equation and it was observed that the experimental values confirm the theoretically proven co-relationship.
item: Conference-Abstract
Design and realization of pogrammable induction motor drive
(2008) Kurnarawadu, S; Ranindu, D; Rathnayakae, G; Sreeskanth, V; Sriragu, A; Sudarsan, Gl
There are different algorithms available for speed control of induction motors, while every algorithm has its relative merits over the other. The inverters available in the market are mostly designed using application specific ICs and a specific algorithm is implemented. This paper discusses about design of programmable induction motor drive, which implements different algorithms using new type of controllers and technology as a one system. In addition to this, the critical design issues in developing a motor drive such as dead band time implementation, optical isolation of circuits, overvoltage and overcurrent protection and precise speed sensing and are discussed.
item: Conference-Abstract
Design of an ergonomically efficient chair
(2008) Gopura, RARC; Amarasena, KGAH
Ergonomically designed chairs are important for long time seated workers to increase their productivity and also to reduce low back injuries due to use of poorly designed chairs in ergonomic aspects. In addition, ergonomically designed chairs increase the seating comfortability of the chair users. Most of the chairs designed for the long time seated workers are not considered the full ergonomic aspects. In this paper, we discuss a design of an ergonomically efficient chair for the long time seated workers to increase their productivity and also to reduce low back injuries.
item: Conference-Abstract
Design of automatic voltage regulator and frequency governor for synchronous generator
(2008) Karunadasa, JP; Kumara, GRME; Paranietharan, A; Vishnukanth, S; Gamachchige, MSW
This paper presents the development of an Automatic Voltage Regulator (AVR) and a Frequency Governor for synchronous generator for laboratory purposes. The AVR operates as a voltage stabilizer and controller because the output voltage is controlled and regulated through a digital system. The Frequency Governor controls the frequency of the output voltage by means of controlling rotating frequency of the generator. Insulated gate bi-polar transistor switches are used to control the excitation voltage of the generator and the armature voltage of the DC motor to control the outputs.

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Browsing ERU - 2008 by Conference "Research for Industry"