Browsing by Author "Jayasinghe, JAKS"

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item: Conference-Full-text
Automated traffic signal controller with remote accessibility
(1999) Jayasinghe, JAKS; Arachchi, HK
Development of the hardware, firmware and control and monitoring software to interface the UNIROAD Traffic Signal Controller (TSC) to Advanced Traffic Control System (ATCS) is described. This system is capable of controlling and monitoring traffic signal controllers over a standard telephone link. It is specially developed at a low cost for third world countries such as Sri Lanka.
item: Conference-Full-text
Capacitance method based handheld device to measure the moisture content of static grain
(2011) Maxworth, AS; Porambage, PL; Mallawa, MTBP; Dias, KNG; Jayasinghe, JAKS
Quality of the grain depends on the interna! moisture content. Capacitance method was used to determine the moisture content of static grain with accuracy of ±0.9%. This paper represents the characteristics and operation of a handheld device which was made to give real-time moisture content readings based on the capacitance of the grain with the above accuracy for paddy.
item: Thesis-Abstract
CCTV Based sensing techniques for adaptive control of traffic signals in multiprocessor architectures
Nishantha, GGD; Jayasinghe, JAKS
As the problem of urban traffic congestion spreads, there is a pressing need for the introduction of advanced technology and equipment to improve the state of the art of traffic control. In this context, the techniques used for sensing traffic flow information plays a vital role, ensuring accurate real time controllability. Closed Circuit Television (CCTV) has gained popularity because of its ability to provide diverse information on relatively large regions leading to opportunities for performing substantially more complex tasks than conventional detection schemes. By processing these video images, traffic parameters such as speed, traffic composition, queue length etc. can be extracted. In addition CCTV images can be further processed for other useful information such as detection of vehicle shapes, vehicle types, occurrence of traffic violations and vehicle identification numbers etc. To introduce CCTV based vehicle detection for automation of road traffic control in Sri Lanka involves an unaffordable investment cost to purchase foreign technology and equipment unless some locally developed system is introduced. This thesis presents complete design of a CCTV system, which involves multitude of design and implementational aspects. It involves development of an image grabber, a remote communication interface and detection algorithms. In addition to visual monitoring of remote road traffic scenes, the designed system is capable of assessing many different traffic parameters, which can be used for adaptive control of road traffic. The underlined project is an attempt to seek the possibility of introducing image based traffic sensing technology to Sri Lanka. Significant attention has given to reduce the cost of development throughout the project to ensure that the concept of CCTV can be realized in practice in Sri Lanka for road traffic control.
item: Conference-Full-text
A CCTV image grabber for vehicular parameter detection.
(1999) Jayasinghe, JAKS; Nishantha, GGD
The concept of vision information has become a key feature in moden vehicular traffic control and Intelligent Vehicle Highway Systems (IVHS) [1]. Vehicle detection by video cameras is one of the most promising new technologies used in implementing advanced traffic control and management systems [2]. The CCTV Image Grabber discussed in this paper is a low cost design which can capture, store and transmit video information to a remote computer for visual site inspection and extraction of vehicular traffic parameters for adaptive control of road traffic.
item: Conference-Extended-Abstract
Design and development of a hand geometry recognition system for access control purposes
(2004) Samarasiri, BS; Jayasinghe, JAKS; Premaratne, MAUK
In the information age, security is a critical issue faced by many organizations. There are three basic means of letting only authorized people in and keeping unauthorized people out. These are the use of passwords, verification objects such as access cards and biometrics.
item: Conference-Extended-Abstract
Design and development of a rotary transformer testing machine
(2004) Samarasiri, BS; Jayasinghe, JAKS; Peiris, TDK
Rotary transformers are designed to transmit electric signals from a rotating body to a fixed body or from a fixed body to a rotating body. In this regard, it is not possible to use lead wires to carry electrical signals between a rotating and a fixed body. A spring - brush arrangement as used in motors is not also suitable for this task, since it generates high electric noise.
item: Conference-Full-text
Design of a low noise pre amplifier for terrestrial television reception
(1999) Jayasinghe, JAKS
Low Noise Pre-amplifiers (LNP) increase the quality of weak signals by amplifying them without introducing excessive noise generated inside the amplifier. The advantage of using LNP for weak TV signal reception is presented by extensive analysis of signal to noise ratio. A design of a LNP that operates satisfactorily over the 50-750 MHz frequency band is presented in this paper. Cost effectiveness and superior performanceare the salient features of this design.
item: Conference-Full-text
Design of yagi array receiving antennas using genetic optimization
(2000) Jayasinghe, JAKS
YAGI array is a very popular antenna for VHF/UHF applications due to its simple construction. It is extensively used in television and FM radio reception. However, design of YAGI arrays to meet a given set of specifications is a very difficult task. This paper presents a genetic algorithm based design technique for YAGI arrays for receiving applications.
item: Conference-Full-text
Design skills with business attitudes
(Department of Mechanical Engineering, University of Moratuwa, Sri Lanka, 2001-07) Jayasinghe, JAKS; Nanayakkara, LDJF
Any design has no value unless it is related to a marketable product. Engineers have to play a major role In design. This paper describes the new dimensions needing careful considerations in Sri Lankan engineering education.
item: SRC-Report
Development of switch mode UPS
Jayasinghe, JAKS
UPS stands for Uninterruptible Power System- Which simply means a power supply which cannot be broken. Usually any power supply is fed from the commercial power which is distributed by me C.E.B., but this means that any time when there is a commercial power failure power supply is broken or interrupted. Therefore in order to be uninterrupted, this has to be fed with another source of power. That power source is non other than a Lead Acid Battery.
item: Article-Full-text
Development of switch mode UPS
Jayasinghe, JAKS
UPS stands for Uninterruptible Power System- Which simply means a power supply which cannot be broken. Usually any power supply is fed from the commercial power which is distributed by me C.E.B., but this means that any time when there is a commerc*' power failure power supply is broken or interrupted. Thererore in order to be uninterrupted, this has to be fed with another source of power. That power source is non other than a j-eac Acid Battery
item: Thesis-Abstract
Feasibility of including natural gas in Sri Lanka's energy supply, including the design of market parameters
Jayasinghe, JAKS; Samarajeeva, R
Sri Lanka's commercial energy supply is overly dependant on oil and oil related energy. Therefore, the economy is vulnerable to price fluctuations in the international oil market. This thesis seeks to explore the viability of adding Natural Gas to the Sri Lankan energy mix to reduce oil dependence. It has been argued by some that Natural Gas is not an option for Sri Lanka because the size of its energy market cannot support an economically viable Natural Gas industry. In response, three possible future market scenarios are developed in this thesis. Based on international best practices this thesis also proposes an ideal market structure for the Natural Gas Industry, including demarcation of roles for ex ante and ex post regulation. As a greenfield industry, Natural Gas provides unique opportunities for market design. The final conclusion is that there is potential for Natural Gas in Sri Lanka in high economic growth scenarios of 8 -10 per cent of economic growth per annum. The last chapter discusses the importance of regional cooperation in South Asia for fulfilling the energy needs of the country.
item: Thesis-Abstract
Genetic elgorithm based adaptive control of traffic fight systems in multiprocessor architecture
Kodikara, AH; Jayasinghe, JAKS
The traffic signal is one of the most common control devices used to manage highway traffic. Operating them as isolated units does not exploit their usefulness fully. An advanced system, in which traffic signals at junctions at a close proximity are coordinated, enables a more efficient method of traffic control. This thesis presents the development of hardware and software for the Uniroad traffic signal controller, for interfacing it to the proposed Advanced Traffic Control System (A TCS) for Sri Lanka, and a technique to calculate traffic plans based on the Genetic Algorithm for the coordinated system. In hardware development, a communication interface and a general purpose input interface (GPIT) are designed and implemented for the traffic signal controller (TSC). These are used to monitor the performance and change traffic plans manually or through computer control. The GPII is also used to interface vehicle detectors, pedestrian pushbutton etc. to the TSC. The firmware platform of the TSC is developed to accommodate the requirements of both coordinated as well as individual systems. Synchronizing routines, temporary overrides and online time plan adjustments as well as error detecting and logging routines are introduced. A control and monitoring (C&M) software package is developed for the control center. Using this package, the operation of each traffic signal controller can be monitored or optimally adjusted as needed. A traffic plan calculator (TPC) is developed to calculate traffic plans needed for a set of coordinated traffic signal controllers. A new algorithm, based on well-known evolutionary algorithm, the Genetic Algorithm, was developed for TPC. The TPC provides an optimum set of traffic signal plans for a coordinated traffic signal system. This is a one requirement of proposed Advanced traffic Control System for Sri Lanka.
item: Conference-Full-text
Improving the efficiency of electro discharge machining by dual voltage excitation
(2000) Jayasinghe, JAKS
An Electrical Discharge Machine (EDM) is a vital machine used in manufacture of tools and dies. Its operation is based on discharge of an electrical current across the tool and the work-piece. Due to limitations of the servo control system, the EDM operates with a low efficiency using a high spark voltage. This paper presents a novel technique based on a dual voltage excitation for an EDM. Although this technique was developed primarily to improve the efficiency, it reduces the cost and size of the electronic controller as well.
item: Conference-Full-text
Interfacing field device substitutes to central control terminals through interface cards
(2001) Thimirachandra, RS; Jayasinghe, JAKS; Samarasiri, BS
In an integrated plant environment, it is not feasible to replace an existing field device with a different model unless the protocols are properly matched. The system complexity is a deterrent to a software modification in order to tackle the problem. A microcontroller based interface card would be an elegant solution. This card takes information from the new device and manipulates it dynamically so that the central controller can understand and vice versa. Due to the new features of microcontrollers, design and development of such cards are not intricate.
item: Conference-Abstract
Introduction to agriculture electronics to engineering undergraduates
(2014-06-24) Maxworth, AS; Jayasinghe, JAKS
For the development in the agricultural sector in Sri Lanka, it is a well accepted fact that technology should be introduced to the field of agriculture. Here Electronic Engineers can play a major role. As the first step of this process the multi-disciplinary module Agricultural Electronics was formed and introduced to the undergraduates of the specialized field Electronic and Telecommunication. The necessity, content and the outcomes of the module were demonstrated in this paper as a new trend in Engineering Education; therefore any nation would be able to adopt this multi-disciplinary approach for the benefit of their country
item: Thesis-Abstract
Intuitive reasoning for epistemic uncertainty
(2016-05-25) Senaratne, DN; Pasqual, AA; Jayasinghe, JAKS; Kulasekera, EC
Epistemic uncertainty, characterized by subjectiveness and partial availability of information, is associated with the domains of multi-sensor fusion, evidence processing, etc. Mathernatical Theory of Evidence, pioneered by Glenn Shafer [1], is a branch of study seeking to analytically model and manipulate the epistemic uncertainty entertained by an agent. The field is relatively young and cluttered with schemes that are used non-cohesively and often counter-intuitively. Further the issue is made worse as none of the schemes seems to be capable of modeling fully the uncertainty met in practice. Interestingly, humans are capable of intuitively handling such uncertainty in statements in their day-to-day activities. It is apparent that the reasons for deficiencies in existing models is the unjustified nature of their application approaches. This research seeks to enhance the intuitiveness and flexibility in mathematical modeling of epistemic uncertainty. It identifies three aspects, which any model should address cautiously. Namely, the manner in which real world propositions are mathematically represented, the manner in which uncertainty entertained by an agent is conveyed as a number assignment, and the manner in which expressed uncertainty is combined and conditioned. Novel strategies that parallels the way humans reason and hence enhance the intuitiveness, are introduced to overcome shortcomings in the existing mathematical representation. Further it proposes representing support as functions of propositions which are formed using a Boolean algebra on a set of hypotheses representing the context. Handling of some complicated propositions is simplified by introducing N-of, a logical operator formalizing the human notion 'N of n'. The research also proposes methods that can be used to select an appropriate combination strategy based on the contextual relationships between the frames, for a given evidence. It is further noted that the counter intuitive results obtained using the existing combination function's is a direct consequence of one being unaware of this relationship. Latter part of the research focuses on the concept of pre-conditioning, where evidence is conditioned based on external information one deems as certain. It also examines how comparable evidence may be averaged based on pre-determined weights. Although, a couple of novel concepts are introduced, the concepts retains backward compatibility with what is already established in this domain. Being modular, the proposed schemes can be selectively integrated with the existing techniques.
item: Conference-Full-text
Lamp driver & failure detector for incandescent lamps in traffic signal systems
(1999) Jayasinghe, JAKS; Ranaweera, RAKP
The design and implementation of a low cost solid-state lamp driver and failure detector (LD/FD) for incandescent lamps is described. The design is directly targeted for the signal lamp heads in highway traffic signal systems. This is entirely hardware oriented and can be used to replace the relay systems currently used without doing any modification to control signals. The incorporated lamp failure detection circuitry enhances the features of the design by activating a feedback signal to indicate lamp failures. This feature enables us to develop an automated maintenance scheme in a centralized traffic control system such as the emerging Advanced Traffic Control System (ATCS).
item: Conference-Full-text
Multiprocessor architecture for adaptive control of traffic light systems
(1999) Jayasinghe, JAKS
Construction of new highways or expansion of existing highways to meet the ever- increasing highway traffic is a very expensive and time-consuming task. Management of existing highways effectively is considered as a high priority option in Traffic and Highway Engineering. Traffic control by a system of traffic signal lights and variable message signs that can adapt to the changing environment is an essential part of such management scheme. The multiprocessor architecture described in this paper maintains near neighbor connectivity and shares information via these near neighbor interconnections for calculation of optimum traffic plans. The near neighbor connectivity simplifies the expansion of the multiprocessor architecture with city developments.
item: Conference-Full-text
Online automatic charger for maintenance free sealed battery supplies
(1999) Jayasinghe, JAKS; Ranaweera, RAKP
The design and implementation of a high performance, automatic battery charger is described. The main target application of the design is for on-line battery backup systems requiring high reliability such as highway traffic signal controllers. The charger has the capability of charging maintenance-free lead-acid accumulators, where careful charging control is essential. This device can be used to charge normal lead-acid batteries as well.