International Research Symposium on Pure and Applied Sciences (IRSPAS)
Permanent URI for this communityhttp://repository.kln.ac.lk/handle/123456789/15650
Browse
Item The 3D atomic scale and electronic structure characterization of novel fcc ruthenium nanoparticles using synchrotron light source(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Kumara, L.S.R.; Sakata, O.; Kohara, S.; Song, C.; Yang, A.; Kusada, K.; Kobayashi, H.; Kitagawa, H.Ruthenium (Ru) is a 4d transition metal that in the bulk adopts hexagonal closepacked (hcp) structure at all temperature ranges, and novel face-centered cubic (fcc) Ru nanoparticles (NPs) have been observed to be more efficient than conventional hcp Ru NPs larger than 3 nm. It has recently attracted much attention as a potential application in removal of car exhausts due to high catalytic activity for CO oxidation and preventing CO poisoning in fuel-cell system. We here report the 3-dimentational atomic-scale structures of fcc and hcp Ru NPs using high-energy X-ray diffraction (HEXRD), Rietveld analysis, pair distribution function (PDF), and reverse Monte Carlo (RMC) modelling. Hard X-ray photoelectron spectroscopy (HAXPES) can provide important information on the influence of NP size on electronic properties. The HEXRD and HAXPES of Ru NPs were performed at BL04B2 and BL15XU at SPring-8, the world largest third-generation (8 GeV) synchrotron radiation facility located in Hyōgo prefecture, Japan. We observed higher stability of the lattice distortion of fcc Ru NPs with increasing particle size. The PDF analysis results show that the structural disordered Ru NPs at short- to intermediate-range atomic distances. The order parameter for fcc Ru NPs decreased with increasing particle size due to the loosely packing atomic arrangement and may explain an origin of higher catalytic activity of fcc Ru NPs. In this study, the observed trend of increasing catalytic activity of fcc Ru NPs was also discussed using their core-levels and valence band electronic structures. This work was partly supported by ACCEL, Japan Science and Technology Agency (JST) and also partly supported by Ministry of Education, Culture, Sports, Science and Technology of Japan (OS: 15K04616).Item Abhiram, G. and Munasinghe, R. C. (2018). Development of new master batch mixing cycle for a track producing extrusion compound with lower rejection rate(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Thennakoon, T. M. A. D. L.; Withanage, N. S.As rubber shows inherent viscous and elastic properties, mixing of compounding ingredients is the first and most important step in rubber manufacturing. If mixing does not properly happen, many problems will be appeared in the end product leading to higher rejection. Currently, Rubber compounding industry produces track producing extrusion compounds to make continuous band of tread for military, agricultural and construction vehicles around 98% rejection, due to viscosity. Therefore, the focus of this research was to develop a new master batch mixing cycle by modifying the present conditions maintained during mastication phase, carbon black incorporation phase and dispersion phase to reduce the rejection level of track producing extrusion compound. Hence, the mastication phase rotor speed (30 rpm, 40 rpm, 50 rpm), mastication phase masticate time (60s, 80s, 100s), carbon black incorporation phase rotor speed (30 rpm, 40 rpm, 50 rpm) and dispersion phase rotor speed (30 rpm, 40 rpm, 50 rpm) were changed separately to obtain the optimum conditions for each phase giving better viscosity properties of the compound. The results revealed that, the best batches could be obtained under 50 rpm rotor speed and 80s masticate time in mastication phase; 50 rpm rotor speed in carbon black incorporation phase and 40 rpm rotor speed in dispersion phase. Therefore, the new master batch mixing cycle could be considered as 50 rpm rotor speed and 80s masticate time in mastication phase; 50 rpm rotor speed in carbon black incorporation phase and 40 rpm rotor speed in dispersion phase to reduce the present rejection rate of track producing extrusion compound TR-5237.Item Abundance and distribution pattern of Aedes aegypti and Aedes albopictus in selected urban, sub-urban and rural areas of Gampaha District, Sri Lanka(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Dalpadado, C. P. R. D.; Amarasinghe, L. D.The abundance and distribution of Aedes aegypti and Aedes albopictus, vectors of dengue fever, were determined at six localities in Gampaha District, which is the district with the occurrence of second highest number of dengue cases during last five years. Negombo and Wattala areas were selected to represent urbanized communities, Gampaha and Attanagalla to represent sub-urban communities and Dompe and Divulapitiya were selected for the rural communities based on population density. Percentage of premises infected with Aedes larvae (Premise Index) and the number of positive containers for 100 premises inspected (Breteau Index) were used as a proxy to determine the abundance of vectors. Larval collections were done monthly during April 2016 to June 2018 using random sampling technique for minimum 100 houses within a radius of 300 m. Potential breeding places in each site were identified and categorized accordingly. Out of 7916 premises examined, 1011 (12.8%) premises were found to be positive for Aedes mosquitoes. Among them 10.1% and 89.9% were found to be positive for Ae . aegypti and Ae . albopictus, respectively . Ae . aegypti was mostly prevalent in highly urbanized MOH areas (73%) while it showed low abundance in sub urban (21%) and rural (6%) areas. On contrary, abundance of Ae . albopictus was highest in sub-urban areas (47%) and lowest in urban areas (18%). Premise index (PI) for Ae . aegypti in urbanized areas were significantly higher than that of sub-urban (F=9.13, p<0.05) and rural areas (F=15.49, p<0.05) in Gampaha District and there was no significant difference (F=4.04, p>0.05) between PI of Ae . aegypti in sub urban and rural areas. The PI of Ae . albopictus in sub-urban areas was significantly higher than that of urban areas (F=15.43, p<0.05). There was no significant difference (F=1.44, p>0.05) between PI of Ae . albopictus in sub-urban and rural areas. Similarly, there was no significant difference between mix indices for Ae . aegypti and Ae . albopictus in Gampaha district (p>0.05). There was a strong correlation between the Breteau Index and the number of dengue patients reported in urbanized areas (r<0.5). Higher correlation was recorded with Ae . aegypti than Ae . albopictus. Therefore, occurrence of dengue epidemics are strongly correlated with Ae .aegypti indices in city areas of Gampaha District and present study suggests that Stegomyia indices can be used as a proxy to determine dengue transmission risk.Item Accelerate business growth by synergizing emotional intelligence(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Subashini, K. K. P.“Emotions drive people, people drive performance”. Emotional Intelligence is a critical success factor for the sustainable business growth on which professionals need to concentrate. Emotional intelligence is an invisible skill, which can be developed through learning, training and practicing. To be a part of successful, satisfied, high customer delight team, it is important to have positive, effective interpersonal skills as well as high emotional intelligence empowerment. Research has shown that every emotion has a function. Experts opine that “People buy relationships, not products”. To accelerate business growth, professionals need to pay attention of the emotions of the clients. The objective of this paper is to identify the factors that affect the business growth. We used random sampling techniques to collect data. Then we analyzed the data by using statistical tools. We first setup a forum for software professionals to discuss the challenges, limitations and success factors. We then conducted an online survey based on the findings from forum and literature review. Through this, we identified more than 30 challenges and several best practices. We further conducted a set of face-to-face interviews with the subject matter expertise like customer relation managers and sales teams to identify a suitable set of solutions, and finally developed a framework. According to the result shown in the survey, clients are willing to have emotional bond with the development team. Further, 80% of the professionals agreed that emotional connection is one of the main factor for the project success. It has also shown that 70% of the people state that emotional intelligence is a skill, which needs to be trained by the expert for better work environment. 75% of the experts state that emotional intelligence is needed for good personal relationship. 60% of the professionals agreed that empathy is the major factor, which help to have a good work environment. It also found that technical team has to understand the power of emotional intelligence to have good business growth in the organization.Item Accelerating the rate of convergence of some efficient schemes for two-stage Gauss method(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Chamaleen, D.B.D.; Vigneswaran, R.The non-linear equations obtaining from the implicit s – stage Runge-Kutta methods have been solved by various iteration schemes. A scheme has been developed, which is computationally more efficient and avoids expensive vector transformations. The rate of convergence of this scheme is examined when it is applied to the scalar test differential equation = and the convergence rate depends on the spectral radius [()] of the iteration matrix (), where = ℎ and ℎ is the step-size. In this scheme, supremum of a lower bound for [()] is minimized over the left half - plane with the constraints requiring super-linear convergence at = 0 and → ∞ .Two new schemes with parameters are obtained for the two-stage Gauss-method. Numerical experiments are carried out in order to evaluate and compare the efficiency of the new schemes and the original scheme. Consider an initial value problem for stiff system of ordinary differential equations = (), () = , : ℝ → ℝ. An s-stage implicit Runge-Kutta method computes an approximation to the solution x () at discrete point = + ℎ by = + ℎ Σ ( ), where , ,…,, satisfy sn equations + ℎ , ), = 1,2, . . . , . = is the real coefficient matrix and = [ , ,…,] is the column vector of the Runge-Kutta method. Let = ⊕ ⊕ … ⊕ ∈ ℝand () = () ⊕ () ⊕ … ⊕ () ∈ ℝ. Then the above equation in , ,…, may be written by = ⊗ + ℎ( ⊗ )(), where = (1,1, … ,1) and ( ⊗ ) is the tensor product of the matrix with × identity matrix . The efficient scheme, which has been already proposed, is given by [ ⊗ ( − ℎ)] = ( ⊗ )( ⊗ – ) + ( ⊗ )( ⊗ – ) + ℎ( ⊗ )() + ℎ( ⊗ )(), = 1,2, …, In this scheme, supremum of a lower bound for [()] is minimized over ℂ, where ℂ = { ∈ / () ≤ 0 } with the constraints [()] = 0 at = 0 and [()] = 0 at → ∞. The parameters for the two-stage Gauss method are obtained and Numerical experiments are carried out.Item Adaptive green time allocation method for traffic congestion based on cell transmission model and genetic algorithm(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Priyasad, H. A. D.; Kulatunga, D. D. S.Traffic congestion is defined as a physical phenomenon relating to the manner in which vehicles impede each other’s progression as demand for limited road space approaches full capacity. This makes trip time longer and increasing queuing. Also it causes serious problems for the day to day lives of people, massive financial and man-hour loss, environment pollution, some diseases etc. In Sri Lanka, traffic congestion in a given area occurs for many reasons. The main reason is that the demand of road does not match to road capacity. In Sri Lanka, although an increase of 10% per year road demand is expected, it can increase road capacity by around 2% to 3% per year. Other important reasons are the existing traffic control system and traffic intersections. Traffic control systems play a central role of traffic management in Sri Lankan cities. Existing traffic light system mainly controls the traffic light change in constant cycle time. But road conditions in a given area vary day by day. If the traffic control system does not deal with these variations, then traffic control system will create bottlenecks and delays. Therefore, the control of traffic requires adequate adjustments to these variations. This research focused on studying and applying cell transmission model to dynamic traffic signal controlling procedure. Basic cell transmission model is used to model the dynamic changes of vehicular traffic flow and to estimate the total delay of vehicles in a given region within a given time interval under different green time allocations. To find an optimal signal timing plan, the Genetic Algorithm is used. The proposed model is applied with certain assumptions to find an optimal time plan to a signalized intersection in main Kandy - Colombo road which has heavy traffic congestion in the morning hours in weekdays. A section of this region is selected to minimize the total delay and to find an optimal dynamic time plan for the signal lights analyzing the actual data collected in this region using four video cameras. The results are compared with the existing pre-timed signal time plan and the corresponding total delay. It is observed that the proposed dynamic signal timing plan will reduce average delay by 6.2675% and it can be proposed as an alternative for the existing system.Item Agent based modeling for unordered traffic in Sri Lanka – An investigation into pedestrian behaviors.(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Rathnayaka, K. R. K. S.; Rajapakshe, R. A. C. P.Rising traffic congestion is an inescapable condition in large and growing metropolitan areas across the world. If we consider Sri Lanka, in the past it was largely limited to Colombo district but now it is spreading to the other areas as well. Major reasons to occur traffic congestion in Colombo and suburban is unordered traffic behaviors. Main entities of a traffic scenario are pedestrians and vehicles. Therefore, pedestrians too are contributing to the traffic congestions. For example, when the pedestrians walk on roads without using the pavements, vehicles get less space on roads leading to traffic congestions. Jaywalking too can be considered as an unordered behavior. Police makes different rules to control the traffic congestions like charging fine from people who offence traffic rules and opening both side of the road towards one direction in peak hours. From an infrastructure development perspective, authorities make actions to construct underground and overhead pedestrian bridges, fences along pavements, islands, etc. However, most of these initiatives end up with unexpected results, mostly since traffic congestion is an emerging macro-level pattern from complex micro-level behaviors of pedestrians and drivers. We propose Agent-Based Modeling and Simulation (ABMS) approach, which applies computational methods to study issues in complex systems. In this approach, individual vehicles and pedestrians are modeled as agents with a simple set of behavioral rules. When put together in a simulation environment, these software agents interact with each other similar to the way real world vehicles and pedestrians behave, letting us study traffic congestion emerging as a macro-level pattern. In these interactions, the software agents exhibit the types of behaviors similar to those in the real environment such as coordination, collaboration and negotiation. This helps us to get better insights on the causes of traffic congestion and test different control strategies on a computer before implementing in the real world. Prior research has focused on the impact of seepage behavior and lane changing behavior of drivers on traffic congestion. Extending that work, we propose to incorporate pedestrian behaviors to see the overall impact of behaviors of drivers and pedestrians to the congestion. We use the ABMS environment called NetLogo to develop the simulator and Kiribathgoda junction in Western Province, Sri Lanka as the testbed. The objective of this research is to come up with an effective traffic simulator for the unordered traffic conditions in Sri Lanka that could be used by policy makers to analyze different traffic congestion scenarios and test different solutions to reduce traffic.Item An agent-based simulation study on the impact of emerging motorbikes swarms on the transportation system in Sri Lanka(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Kulathilake, E. R.; Rajapakse, R. A. C. P.Transportation system in Sri Lanka is increasingly getting dependent on private modes rather than public modes. In particular, the motorbike has become the most popular mode of transportation among the middle income category of the society. This increasing trend is well reflected in the rush hour traffic as well as in the growing number of motorbike sales outlets appearing across the country. Our research is based on the question where would this end up if this trend continues. As many East Asian countries such as Vietnam, Indonesia and Thailand are currently suffering from the largely unorganized traffic resulted from motorbike swarms, we see the investigation of the possible impact of this growing tendency to use motorbikes in Sri Lanka on the transportation system as a critical issue that the policy makers should be concerned of. We propose to use computational methods to foresee the future by creating simulation models. For this endeavor, we propose the Agent-Based Modeling and Simulation methodology which is a computational method of studying macro level emerging patterns in a system such as traffic congestion by simulating the micro level interactions of individual entities such as individuals, motor bike riders, pedestrians, other vehicles are modeled as software agents. The primary data to construct the model as well as to calibrate its parameters are collected through a questionnaire distributed among motor bike riders as well as thorough literature review. The data being collected include the background of using motorbike as the primary mode of transportation, the issues in the public transportation system as well as the common driving patterns of individual motorcyclists. Once the model is constructed, the simulation results will be compared with the observations in the real environment to validate the model. The validated model will then be used to make predictions about the future and arrive at conclusions about the future traffic patterns. The implications of this study will be helpful to the policy makers to come up with better strategies to reduce the congestion.Item An AHP approach to prioritize the distributor’s requirements while minimizing the transportation cost(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Madushika, I.K.; Wijayanayake, A.Academic and corporate interest in Supply Chain Management (SCM) has risen considerably in recent years as SCM has emerged as one of the major areas for companies to gain a competitive advantage. Basically, the three fundamental stages of a Supply Chain (SC) are, procurement, production and distribution. Among these three stages, distribution plays a vital role as it directly impacts both the SC cost and customer experience. Many models have been developed in the past to minimize transportation cost under different constraints, as the main cost of logistics is transportation. In fact, when the organizations run on cost cutting approaches, not all the customers are satisfied when the demand surpasses the supply. Therefore, to retain the most important customers a proper mechanism is needed to prioritize them. Previous studies have been addressed different problems in logistics and improved models have been developed to maximize the service level and customer satisfaction but prioritization of customers is still a gray area which remains in the logistics literature. One of the main hurdles for distributors is handling situations, where the demand is higher than the supply and selected set of orders have to be delivered. Therefore, the main objective of the study is to identify the most important customers to be delivered first, from the distributor’s perspective while minimizing the cost of transportation. In this study, Analytic Hierarchy Process is used to identify the most important customers to the organization, under different criteria, defined by the distributor. All the criteria and alternatives were compared pair-wisely to calculate the overall importance of the alternatives. A mixed integer linear programing model has been developed with priority values in order to minimize the transportation cost. The proposed model will satisfy the needs of the important customers first and then the rest of the customers will be satisfied with the remaining quantities. When comparing the results of the developed model and ordinary transportation model, the transportation cost is higher in the developed model than the general transportation model. However, the satisfactory level of meeting the demands of the important customers is almost 100%. Therefore, this model is more appropriate for the firms who value customer needs more than minimizing the transportation cost.Item An algorithm for plagiarism detection in Sinhala language(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Basnayake, S.F.; Wijekoon, H.; Wijayasiriwardhane, T.K.According to the Merriam-Webster dictionary, the simple definition of the verb plagiarize is, “to use the words or ideas of another person as if they were your own words or ideas”. Many software tools to aid in detecting plagiarism is available for English language, but equivalent tools are not yet available specifically for Sinhala language. Though language independent tools that work on many languages are available, they generally give poor results as they do not consider language specific features. There are some detection methods proposed for Asian languages like Hindi, Malayalam, Arabic and Persian which have some close relationship and similar properties of Sinhala language. All of those methods use language specific rules and they even outperform the commercially available tools. These findings are evidence that the language specific plagiarism detection is more effective than the language independent plagiarism detection as some paraphrasing techniques can be used to mislead the language independent systems.Sinhala language is constitutionally recognized as the official language of Sri Lanka, along with Tamil. Due to the complexity of the language structure and rules of grammar, the language independent tools seem to provide poor results when used for plagiarism detection in Sinhala documents. In this research, we propose a novel plagiarism detection algorithm built around content based methods specific to Sinhala language. The methodology of this study follows both experimental and build approaches. The proposed plagiarism detection system has two modules namely, text pre-processing module and the similarity detection module. The text pre-processing module pre-process the text files to standardize the text sources using techniques such as stop word removal, number replacement, lemmatization, synonym recognition and creating n-grams. Then the similarity detection module analyses the pre-processed text using Jaccard coefficient and cosine similarity coefficient to measure the similarity between two documents. A prototype of Sinhala language plagiarism detection system will be implemented using the proposed method and several combinations of the above techniques will be used to discover the best combination. Testing and statistical performance evaluation will be carried out using a sample of source text files and plagiarized text files in Sinhala language by taking expert judgements also into the consideration. The final outcome of this research study is to develop an effective software application for plagiarism detection in Sinhala language documents.Item Algorithm to identify the original web links and suggest optimized mirror links for download content within a web page.(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Karunarathna, G. L. S. I.; Liyanage, U. P.Invention of the Internet has become a revolutionary change to the world. People use different technologies to connect to the Internet. Surfing Internet has become a stressful activity due to the existence of various spams and redirections. Consequently, internet surfers suffer from wasting time and money on in relevant web contents every day. Further, looping redirections caused to distract many internet surfers all over the world. Though the adware blockers come to the stage for preventing unwanted ads, it does not come with handy solution for assisting web surfers to direct the desired web content or resource. At the same time, there can be lots of mirror links, which are available for refer the same web content or resource. If the web surfer is provided desired content targeted and optimized mirror link/s that has minimum traffic and higher bandwidth with minimum estimate time to download the file, it will be much more useful. The purpose of the research is to achieve the solution for suggest original link to download and provide optimized download link. A chrome extension, which is run in chrome browser, is built with all the proposing components and algorithms in order to proof of the concept. Through this highlight original resource link in the web page and pointing fake/redirect links in the web page. Define an algorithm to suggest optimized mirror link to download among the original mirror links. The tool supposed to cache all the metadata of the referred links and validate links time to time with update latest state of the links. The ultimate objective is to derive an algorithm to avoid fake web redirection links and download resources in cost effective manner. Additionally, the software solution implementing this algorithm protect the computer system by avoiding the links that contain harmful malwares and virus. This proposed software solution will develop as platform independent chrome extension and deploy to ensure the optimum and safe internet surfing.Item An alternative sulfur precursor for chemical bath deposition of CdS thin film(Gajanayake, G. K. U. P., De Silva, D. S. M and Atapattu, H. Y. R. (2019). An alternative sulfur precursor for chemical bath deposition of CdS thin film. 4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka. p98, 2019) Gajanayake, G. K. U. P.; De Silva, D. S. M.; Atapattu, H. Y. R.Solar energy is the most appropriate electrification method for a tropical county like Sri Lanka. At present, Sri Lanka generates more than 72% of its electricity needs at a high cost by burning coal and diesel. To overcome the major obstacle of high initial cost in installation of solar power plants, many research groups worldwide at present are focusing towards manufacture of low cost and highly efficient photovoltaic cells based on cadmium sulfide and cadmium telluride (CdS/CdTe) semiconductors. Among the range of methods available for fabrication of CdS window layer, the chemical bath deposition (CBD) is an ideal method due to its simplicity and low cost. In this study, CdS layers were deposited on the FTO glass substrate by CBD method, using an alternative sulfur precursor; ammonium thiosulfate ((NH4)2S2O3) against the well-established but costly precursor thiourea (CS(NH2)2). The CBD bath was prepared with 0.25 mol/L cadmium acetate (Cd(CH3COO)2), 1.00 mol/L ammonium acetate (NH4COOCH3), concentrated NH4OH (pH adjuster), and 0.50 mol/L (NH4)2S2O3. The best growth condition for CdS was identified by varying the parameters; Cd:S ratio, pH, deposition temperature, and deposition time while preserving a constant stirring speed. Uniform CdS layers rich in Cd, were observed in an alkaline electrolyte with Cd:S ratio of 2:5 at a temperature of 95 °C in 90 minutes. The spectrophotometric studies revealed the energy band gap of the material as 2.41 eV which is the typical value for CdS. Further, the X-ray diffractions observed at angles of 26°, 28°, 36°, and 53° representing the planes of (002), (101), (102), and (201) verified the cubic structure, while the scanning electron microscopic studies confirmed the uniform surface morphology of the material with average grains sized of 105 nm. However, the presence of pin-holes observed in the cross-sectional view implied the need of further optimization of parameters to obtain materials comparable to thiourea based chemical bath deposited CdS layers.Item Analysing mobility patterns of people to determine the best transportation method(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Senanayake, J.M.D.; Wijayanayake, W.M.J.I.With the technological enhancements related to Internet, Wireless Communication, Big Data Analytics, Sensor-based Data, and Machine Learning; new paradigms are enabled for processing large amount of data which are collected from various sources. In the past decades, both coarse and fine-grained sensor data had been used to perform location-driven activity inference. In recent years, GPS phone and GPS enabled PDA become prevalent in people’s daily lives. With such devices people become more capable than ever of tracing their outdoor mobility and using locationbased applications. Based on the collected data from these GPS enabled devices with the help of IoT related to user mobility lots of research areas are opened. In this research the data related to user locations when users do any outdoor movements is collected using the mobile devices that are connected to the Internet and is mined using data mining techniques and come up with an algorithm to model & analyse those big data to identify mobility pattern, traffic prediction, transportation method satisfaction etc. The data for this research will be collected using a mobile application which has to be installed in smart devices like smart phones, tablet PCs etc. In this application the user has to enter the activity that he or she currently doing and the method of transportation & the users' opinion on the transportation method if he is doing some sort of travelling. The GPS coordinates (longitude & latitude) as GPS trajectories along with the time stamp and the date will be automatically acquired from the users' IoT device. A cloud based storage will be used to store collected data. Since the dataset is going to be a huge one, there can be data which contains outlier values due to the uncertainty of the mobile network coverage and the GPS coverage of the devices. Therefore, these data should be properly cleaned when doing data mining activities otherwise these data will lead to incorrect results such as wrong traffic prediction in certain places if several users are stuck in the same GPS coordinates for a while. Not only that but also when it comes to the user satisfaction, it might lead to generate incorrect outcome if the users in the sample will not enter their satisfaction accurately. This can be avoided by comparing cluster wise users with the consideration of the location and the transportation method. We can get the average opinion of the users and take it as the satisfaction of the transportation method in that cluster. Using the final results of this research the government can also be benefited if we selected the sample users well with mixing all the types of people and by providing necessary information for planning smart cities.Item Analysis for maximum energy transfer from existing DC-to-DC converter topologies.(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Nagahapitiya, N. W. H. G. B.; Jayatissa, N. W. K.A voltage regulator is an electronic device, which maintains a constant output voltage for varying input voltages. There are different types of voltage regulators with various types of control schemes to achieve great accuracy and fast regulation but it requires more complex circuitry and cutting edge technology. The direct current-to-direct current (DC-to-DC) power converters are designed to provide unregulated dc voltage inputs and to regulate constant voltage output. DC-to-DC converters are applicable to a variety of applications including power supplies of personal computers, office equipment, spacecraft power systems, laptop computers and telecommunication equipment as well as DC motor drives. Thus, high efficiency is invariably required in DC-to-DC converters for maximum energy transfer in these kinds of applications. In this study, theoretical and practical analysis were done on existing DC-to-DC converter topologies. Moreover, behavior of Buck and Boost converters with variable Inductor, variable Capacitor and different duty cycles were investigated in detail. Also, change of output voltage waveform with the above three factors was analyzed. Three basic DC-to-DC converter topologies were analyzed by using theoretical calculations and transfer functions of the converters were derived. Further, Buck and Boost converter was analyzed significantly in practical method. Then results of both the sections were compared to understand the behavior of converters. Introducing a input filter to the switching converter significantly reduced the switching harmonics in the input stage. Another important factor of introducing an input filter is that the control of electromagnetic interference (EMI) appeared in the input signal. So in this study, this phenomenon was analyzed with different types of input filter combinations. The switching converters are the controller unit of the converters. The clarity of the pulse with modulated (PWM) signal is important for stable controller output. This study reveals a technology to provide stable output voltage from distorted PWM signal.Item Analysis of a stochastic predator-prey model(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Prasadini, K.D.S.; Mallawa Arachchi, D.K.In biological systems Lotka-Volterra predator-prey model describes the population dynamics of two interacting species of predators and its preys. Classical predatorprey model is a primitive deterministic model governed by the two differential equations, namely, = ( − ) and = ( − ) where and denote prey and predator respectively, and , , and are parameters. This model can be improved by introducing stochasticity that accounts for the random fluctuations of a realistic predator-prey dynamical system. In this research work, we use Stochastic Differential Equation (SDE) approach. There are various ways, based on various assumptions, to incorporate SDE. One common approach is to use equations of the following form: = ( − ) + ( + ) = ( − ) + ( + ) These types of Stochastic Differential Equations (SDE) can be simulated in Matlab using numerical methods such as Euler-Maruyama method. Phase planes of the deterministic and stochastic models are carried out to demonstrate the behavior of this modified model. Our initial goal is to compare different stochastic models with the original deterministic model through simulations. The deterministic model has a positive equilibrium which is globally stable for positive values of the parameters. Nevertheless, in the stochastic model, the predator and prey populations may tend to extinction. Extinction percentages of predator or prey population are summarized and analyzed through this research work.Item Analysis of a stochastic predator-prey model(Faculty of Science, University of Kelaniya, Sri Lanka, 2016) Prasadini, K.D.S.; Mallawa Arachchi, D.K.In biological systems Lotka-Volterra predator-prey model describes the population dynamics of two interacting species of predators and its preys. Classical predatorprey model is a primitive deterministic model governed by the two differential equations, namely, ���� = (������ − ��������) ���� and ���� = (�������� − ������) ���� where �� and �� denote prey and predator respectively, and ����, ����, ���� and ���� are parameters. This model can be improved by introducing stochasticity that accounts for the random fluctuations of a realistic predator-prey dynamical system. In this research work, we use Stochastic Differential Equation (SDE) approach. There are various ways, based on various assumptions, to incorporate SDE. One common approach is to use equations of the following form: ���� = (������ − ��������) ���� + ��(���� + ����)�� ������ ���� = (�������� − ������) ���� + ��(���� + ����)�� ������ These types of Stochastic Differential Equations (SDE) can be simulated in Matlab using numerical methods such as Euler-Maruyama method. Phase planes of the deterministic and stochastic models are carried out to demonstrate the behavior of this modified model. Our initial goal is to compare different stochastic models with the original deterministic model through simulations. The deterministic model has a positive equilibrium which is globally stable for positive values of the parameters. Nevertheless, in the stochastic model, the predator and prey populations may tend to extinction. Extinction percentages of predator or prey population are summarized and analyzed through this research work.Item Analysis of bus transport service reliability – Case Study from Gampaha bus halt for Veyangoda to Pasyala bus route (Route No -189).(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Athapaththu, A. M. P. L.; Waravita, S. H. H.; Weerasekara, T. C.; Sharic, A. H. S.The objective of this research is to measure the bus transport service reliability of a bus route at a bus halt. Three measures, Coefficient of Variation (CV), Earliness Index (EI) and Width Index (WI), were used to measure the bus service reliability of bus route 189 (Veyangoda to Pasyala) at Gampaha bus halt in weekday and weekends for different time intervals. CV is defined as the ratio of standard deviation of scheduled headway deviation and mean scheduled headway deviation of buses at the halt. Headway deviation is the difference between actual headway and scheduled headway of buses. The scheduled headway at a stop is defined as the difference between the scheduled stop times of the consecutive two buses at the same stop. Actual headway is defined as the difference between leave times of the consecutive two buses at the same stop. The EI (Earliness Index) is defined as the percentile rank of delay/headway deviation of zero. The percentile rank of a particular delay/headway deviation is the percentage of delay/headway deviations in its frequency distribution that are lower or equal to it. WI is defined as the difference between the 95th percentile of headway deviations and the 5th percentile of headway deviations divided by the average scheduled headway. The data for scheduled arrival time, scheduled leave time, actual arrival time and actual leave time of buses at Gampaha bus halt for Veyangoda to Pasyala route were collected from timekeepers for 10 days including week days, weekends and a holiday from 1st February to 10th February 2019 which consisted records of 488 buses that arrived and departed the Gampaha bus halt. Convenience sampling method was used to determine these days. Each day was divided into 4-time intervals. The time intervals were 6 a.m. – 9 a.m., 9 a.m. – 12 p.m., 12 p.m. – 3 p.m., and 3 p.m. -6 p.m. Data analysis revealed that buses operated between 9 a.m. – 12 p.m. were more reliable compared to the other buses operated in other time intervals on weekdays as the CV value was as lesser as 0.53. It was found that buses operated between 12 p.m. – 3 p.m. were more reliable compared to the other buses operated in other time intervals on weekends as the CV value was as lesser as 0.43. But buses were more unreliable between 3 p.m. -6 p.m. on both weekdays and weekends as the CV values were 1.00 and 0.78 respectively. EI analysis revealed that as large as 32% of the buses operated in between 12 p.m. – 3 p.m. on weekdays departed early and as large as 50% of the buses operated in between 3 p.m. -6 p.m. on weekends departed early. WI value was as large as 2.78 between 3 p.m. -6 p.m. while the WI value at the same stop between 9 a.m. – 12 p.m. was 1.42 on weekday. WI value was as large as 1.41 between 9 a.m. – 12 p.m. while the WI value at the same stop between 3 p.m. -6 p.m. was 0.35 on weekends. WI analysis revealed the changing pattern of service reliability in different times of the day. This research describes methods of measuring variations in bus service reliability using secondary dataItem Analysis of heavy metal levels in rice grown in CKDu effected Krambankulama in Medawachchiya, Sri Lanka(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Dilrukshi, A. A. S.; Weerasooriya, M. K. B.Chronic Kidney Disease of unknown etiology (CKDu) is a major health problem faced in agricultural areas in North Central Province, Sri Lanka. Among many different causative factors that suspects, heavy metal contamination of food is one of the major issues which can lead to the renal failures in human. Though number of studies have been reported on CKDu, exact causative factor still remains unknown. Since rice (Oryza sativa) is the staple diet in these areas, heavy metal content of rice grown in CKDu prone Karambankulama, Medawachchiya was aimed to investigate. Rice samples (n=45) were collected from 5 sites in Karambankulama and in Hettipola, Kuliyapitiya. From each site 9 samples were collected at random locations. For the comparison purpose, Hettipola was selected as negative control site. The rice samples were acid digested in a microwave digester and heavy metals were analyzed using Atomic Absorption Spectrophotometer. Cu, Cr, Pb were detected in flame mode whereas Cd was detected in furnace mode. According to the results obtained mean metal contents of rice samples were as follows. Cu- 0.864±0.090 mg/kg, Cr- 0.903±0.020 mg/kg, Pb- 0.144±0.010 mg/kg and Cd-0.089±0.003 mg/kg for the samples collected from Karambankulama and Cu- 0.804±0.050 mg/kg, Cr- 0.895±0.010 mg/kg , Pb- 0.133±0.001 mg/kg and Cd- 0.061±0.001 mg/kg for the samples from Kuliyapitiya. There were significant difference (p<0.05) of the mean levels of Cu, Pb and Cd in rice between Karambankulama and Hettipola while there was no significant difference (p>0.05) with respect to the mean levels of Cr. To assess the safety of dietary intake, weekly intake of Cu, Cr, Pb and Cd in rice samples were calculated separately based on the daily consumption of rice and compared with the Provisional Tolerable Weekly Intake (PTWI) established by the WHO/FAO. The results indicated that weekly intake of Cr was higher for ages between 4-5 years and 14 years for both sites and that of Cd was higher for ages between 4-5 years in Karambankulama than the maximum weekly intake levels recommended by WHO/FAO. During the survey 12 CKDu patients were recorded in Karambankulama whereas none was recorded in Hettipola. Hence, Cd accumulation in the body over long period of time could be one of the causes for the present increase in chronic renal failure in the North Central province.Item Analysis of queuing behaviour in commercial banks: a case study(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Rambandara, R. D. S. S.; Hansani, W. A. D. I.; Arachchige, K. G. B.; Rasanjana, K. A. N.; Sonali, A. L. D. D.Studying queuing behaviour has become a widely explored research area at the time. The practical scenario of waiting lines must be daily experienced by almost everyone. Banking services are foremost among the places where queues are formed. Proper management of banking queues is enhanced for improving customer satisfaction. This study was undertaken with the aim of reducing customer waiting time in a preferred commercial bank of Sri Lanka. The bank had two counters, thus two queues were experienced enabling the system to behave as a multi-server queueing system with limited waiting room capacity and unlimited population size. The system was observed for two hours during two consecutive weekdays. The sample comprised 150 observations on customer arrivals to the queues, arrivals to the counters and departures from the counters. The system was modelled using the student version of Rockwell ARENA 14.5. The study assumed customer arrivals were random and independent, there was no idle time for the counters and the customers were served on first-in-first-out basis. ARENA Input Analyser recorded the probability distributions of inter-arrival rates for queue 1 and queue 2 to follow Gamma and Exponential distributions while corresponding service rates followed Weibull and Normal distributions. The model was run for a replication length of one hour. The waiting times of customers in two queues were observed to be 10.48 and 2.51 minutes. The system permitted 57 customers into the bank and 42 were served and sent out recording a performance rate of 73.68%. Higher waiting times stimulated the necessity of improving the performance of the counters. Thus the quantity of the allocated resources was reformed to conclude an optimal result. When the number of resources was changed separately, the total time spent in the system was decreasing, but several waiting times recorded higher values than the current system. Consequently, the resources of both counters were changed at once resulting no waiting time in queue 1 and 0.22 minutes in queue 2. Further, the total waiting time in the system was observed as 2.79 minutes. Moreover, the system served 54 out of 57 customers. This recorded a performance rate of 94.74% which is more feasible than the current system. Thus the study proved that the bank can eliminate excessive waiting times of customers and improve its efficiency through proper utilization of resourcesItem Analysis of selected, commercially available inorganic fertilizers and soil NPK content in Puhudivula; Medawachchiya(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Sahlah, M. A. H. F.; De Silva, R. C. L.The increased prevalence of CKDu confined to specific geographical regions and among specific occupational groups of Sri Lanka has drawn the attention of scientific community in recent years. This study was conducted to investigate possible contributions of inorganic fertilizer usage on the disease prevalence at Puhudivula; Medawachchiya. Five commercially available fertilizer samples (Urea, TSP, MOP, TOP and Chili mix) most commonly used in the study area were analyzed for their NPK content and trace metal amounts. The NPK composition, calcium content and physiological properties of soil were also analyzed in five selected sites. The total nitrogen amounts were determined using standard Kjeldahl procedure. Total phosphate content of fertilizers was analyzed using ammonium vanadomolybdate method while both total phosphate and inorganic phosphate amounts in soil were determined using molybdenum blue method. The potassium and calcium amounts were determined using flame photometry. The percentage NPK compositions of the analyzed fertilizer samples agree with the percentage compositions listed by the manufacturers for each fertilizer. However, less total nitrogen and less phosphate percentages were measured in Urea and TSP respectively. The NPK composition of soil followed N% > K% > P% order with overall mean concentration of NPK between 279.4-1537.3 mg/kg, 32.4-193.7 mg/kg and 3.0-25.5 mg/kg respectively. The mean calcium concentration in soil was high, ranged from 537.27-1007.75 mg/kg. The trace metals Cd, Pb, Cr, Zn, Cu and Fe in fertilizer samples were analyzed using Atomic Absorption Spectrometer. From the analyzed trace metals, Fe exhibited a remarkable presence in all analyzed fertilizers except Urea with an overall mean concentration >1550.0 mg/kg and the mean concentrations of Cd, Pb and Cr followed the phosphate percentage by weight. Cd and Pb mean concentrations ranged from 0.23-1.80 mg/kg and 0.94-7.17 mg/kg respectively and were below the WHO maximum acceptable concentrations. According to the results, the addition of fertilizers did not increase the heavy metal levels in soil significantly unless it accumulates, and the excessive use of inorganic fertilizers mainly the ammonium-based fertilizers in already nitrogen enriched soils indicates to be causing the acidification of soils and it is evident that it may be mobilizing the calcium ions from its immobile form. This study provides new data to relevant authorities to limit the excessive annual fertilizer input on these lands through proper NPK analysis prior to application.