IRSPAS 2017

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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.
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.
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.
Anti-oxidant activity of selected endo lichenic fungi (ELF) in mangrove ecosystem of Puttalam lagoon.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Maduranga, H.A.K.; Attanayake, R.N.; Amarasinghe, M.D.; Weerakoon, G.; Paranagama, P.A.
Natural products based drug development has become an attractive area of research since there are limited options available to treat certain non-infectious diseases such as diabetes. Among these natural products, it has been reported that secondary metabolites of endolichenic fungi (ELF), have the ability to produce promising bioactive compounds. The objectives of this research were to isolate and identify ELF inhabiting mangroves in Puttalam lagoon, Sri Lanka using classical and DNA barcoding approach and to determine anti-oxidant activity of their secondary metabolites. Lichen hosts were collected from Puttalam lagoon in two different sites near, Athathale and around the NARA institute. The ELF were isolated following a standard procedure: a small piece of the thallus was surface sterilized, cut into pieces and dried on sterilized filter papers and then placed on malt extract agar in Petri dishes and incubated at room temperature (28 ⁰C – 30 ⁰C ) . Once pure cultures were obtained, seven isolates were randomly selected for DNA extraction following standard procedures. Quality of DNA was checked by agarose gel electrophoresis. Fungal internal transcribed spacer (ITS) region was amplified using polymerase chain reaction (PCR) with universal ITS 1 and ITS 4 primers and PCR products were sequenced using Sanger dideoxy chain-termination technology. DNA sequences were edited using BioEdit software and compared with the available sequences in the GenBank using Basic Local Sequence Alignment Search Tool (BLAST). In addition, morphological characterization of each fungal isolate was also carried out. Secondary metabolites from each isolate were extracted with ethylacetate separately and the solvent was evaporated under reduced pressure to obtain the crude extract. Free radical scavenging activity of the extracts were evaluated using 2, 2-diphenyl-1-picrylhydrdrazyl (DPPH) assay. Based on the highest sequence similarity to the GenBank sequences, isolates were identified as Diaporthe arengae (98 %), Neurospora crassa (100%), Lasiodiplodia theobromae (100 %), Schizophyllum commune (98 %), Diaporthe musigena (98 %), Hypoxylon anthochroum (98 %) and Nigrospora sphaerica (98%). IC50 values of extracts of Diaporthe arengae, Neurospora crassa and Lasiodiplodia theobromae were 375.9± 0.062μg/mL, 304.9±0.057 μg/mL and 211.2± 0.086 μg/mL respectively. Since percent inhibitions of the rest of the isolates were less than 50 % in the test doses, IC50 values were not calculated. All of the values were compared with standard Butylated Hydroxy Toluene (BHT) (IC50=108.0±0.072). Out of the seven ELF tested, L. theobromae showed the highest DPPH radical scavenging activity. Further testing of the rest of the isolates are being carried out and ELF may provide a good source of antioxidants for biotechnological applications.
Anticancer activity of Trichoderma harzianum extract against NCI-H292 lung cancer cells.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Sinthujah, S.; Samarakoon, S. R.; Tennakoon, K. H.; Attanayake, R. N.; Weerakoon, G.; Gunasegara, D. S.; Paranagama, P. A.
Cancer is one of the leading causes of death worldwide. Chemotherapy has been the choice of cancer treatment for many years however, it can also affect normal cells and create many undesirable side effects and have the potential to develop resistance. Therefore, investigators must reassess their approach to translate discovery research into greater clinical success and impact aiming to find novel compounds. Endolichenic fungi (ELF) are potential source of producing many bioactive compounds. Preparations of ELFs extracts are commonly used to search for anticancer activity. Based on the fact that fungal extracts provide evidence to develop anticancer drugs, this study was conducted to evaluate the anticancer activity of an ELF, Trichoderma harzianum, (strain No: MF029755) extract against NCI-H292 lung cancer cells. Organ specific in-vitro assays are imperative in large scale screening of natural products with useful clinical activity. Among many such assays, sulforhodamine B (SRB) assay employs a protein binding aminoxanthene dye, to provide a quantitative analysis of viable cells in a culture following the introduction of the compound. Preliminary investigations revealed that crude ethylacetate extract of an endolichenic fungus, T. harzianum, and chloroform fractions of crude extract (12.5 mgL-1, 25 mgL-1, 50 mgL-1, 100 mgL-1 and 200 mgL-1) obtained by partition were positive for the SRB assay. IC50 values of crude extract and the chloroform fraction were 68.48 mgL-1 and 38.44 mgL-1 respectively. The chloroform fraction was chromatographed over silica gel column to obtain seven fractions. Cytotoxicity of the seven fractions obtained from the crude extract of the fungus was determined using SRB assay against lung cancer cell line NCI-H292 following standard protocols. The cell suspension in Dulbecco’s Modified Eagle Medium (DMEM) was aliquoted into 96-well plate. After incubation cells were treated with two concentrations (100 mgL-1 and 200 mgL-1) of fractions obtained by column chromatography. SRB dye was added to each well and acetic acid was used to remove unbound dye. Absorbance was measured at 540 nm using microplate reader. Survival percentage of the cells was calculated. If no viable cells present pink color of the medium turns colorless. In the current assay control wells and 1st fraction remained pink and all the other treatments turned pink into colorless. Seventh fraction showed the highest activity and further purification, SRB assays and structure elucidation will be carried out.
Antimicrobial activity of selected spices against Pectobacterium carotovorum isolated from some vegetables in Sri Lanka.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Wasana, W.P.; Kuruppuarachchi, K.A.P.P.; Yapa, P.N.; Hettiarachi, S.
Bacterial soft rot caused by Pectobacterium carotovorum (Erwinia carotovora) is a destructive disease found worldwide, resulting in economic loss. It is important to implement disease control measures and management strategies in order to prevent economic and further crop losses. Antibacterial nature of spices offer promising solutions to pesticidal hazards, environmental pollution, and pesticide residues in crops and to ever increasing cost of plant protection operations. Although there are a number of studies on the antibacterial nature of spices on various pathogens, its effect on Pectobacterium carotovorum is unknown. Therefore, this study was carried out with the objective of determination of the antimicrobial activity of selected spices against Pectobacterium carotovorum. Specific objectives were to determine minimum inhibitory concentration of aqueous and ethanolic extracts of selected spices against Pectobacterium carotovorum. Disease samples of Allium porrum, Solanum tuberosum, Brassica caulorapa, Daucus carota, Allium cepa, Phaseolus vulgaris, Brassica oleracea var. capitata and Raphanus sativus were collected from various geographical regions in Sri Lanka. These samples were transported in an icebox to laboratory at Faculty of Applied Sciences, Rajarata University of Sri Lanka for further experiments. Pectobacterium carotovorum colonies were isolated on MacConkey agar and pure cultures obtained. Different Pectobacterium isolates were identified using physiological, biochemical and pathogenicity tests. The crude aqueous and ethanolic extracts of nine spices, garlic (Allium sativum), garcinia (Garcinia cowa), cinnamon (Cinnamomum verum), tamarind (Tamarindus indica), clove (Syzygium aromaticum), mustard (Brassica nigra), turmeric (Curcuma longa), pepper (Piper nigrum) and ginger (Zingiber officinale)) were prepared with concentrations of 0.005 g/ml to 0.5 g/ml. Extracts were assessed for antibacterial activity by agar well diffusion method. Sodium hypochlorite was used as the positive control while sterilized distilled water and ethanol were used as negative control. The zones of inhibitions were measured after incubation at room temperature for 24 hours. Among the nine spices, only four spices, garlic, garcinia, cinnamon and tamarind were active against P. caratovorum. The largest zone of inhibition was shown by aqueous extract of garlic while the aqueous and ethanolic extracts of cinnamon showed lowest zones of inhibition. The ethanol extract of garlic had the highest diameter of zone of inhibition among ethanolic extracts of spices. There was no significant difference (p>0.05) in inhibition zones between aqueous and ethanol extract of a particular spice. Aqueous and ethanol extracts of clove, ginger, mustard, pepper and turmeric were unable to inhibit the bacterium with the tested concentrations. Minimum inhibitory concentrations of the spices, which inhibited the growth of Pectobactrium were 0.5 g/ml. The 0.5 g/ml aqueous extract of garlic possess an effective antibacterial activity against P. carotovorum and can be used as cost effective and eco-friendly preventive strategy to eliminate P. carotovorum rather than using chemical control methods. Evaluation of antibacterial activity of these extracts in field, is needed before a cost-effective formulation is developed.
Antioxident activitiy and α-amylase activity of pressurized water extract of Cinnamomum zeylanicum (L.) bark oil.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Wariyapperuma, W. A. N. M.; Jayawardena, B. M.; Kannangara, S. D. P.; Wijayasinghe, Y. S.; Skandaraja, S.
Cinnamon (Cinnamomum zeylanicum) is an evergreen plant widely grown across Asia as a spice and to extract its essential oil. The composition of essential oil, obtained from different parts of the plant differ in chemical composition. Further, the extraction method would also influence the chemical composition of the essential oil. The aim of the current study was to examine the use of pressurized water to extract oil from Cinnamomum zeylanicum bark and to determine whether this extraction method would give a higher quality oil with enhanced anti-diabetic properties. Bark of Ceylon Cinnamon was powdered and extracted using pressurized water (0.098 MPa). The extract was tested for the total phenolic content (TPC), percentage reducing activity, content of condensed tannin and IC50 values for α-amylase inhibition using Folin-ciocalteu method, vanillin assay and ferric reducing antioxidant power assay respectively. The extract obtained by soxhlet extraction was used as a control. The results showed that percentage yield, the content of total phenolic and content of condensed tannin were 4.24%, 0.065 g gallic acid equivalent/ g extract and 0.012 g catechin equivalent/g extract, while those for the control were 5.16%, 0.19 and 0.015 respectively. The ferric reducing power and the pancreatic α-amylase inhibition (IC50 value) were 203.71 and 50.03 μg/mL for pressurized extract and 260.20 and 38.91 μg/mL for control respectively. Present study reveals that cinnamon bark oil obtained using pressurized water has comparable values for phenolic content, reducing power and α-amylase inhibition compared to soxhlet extraction.
Applicability of adaptive machine learning algorithm for improving reading and comprehension capabilities of dyslexic patients.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Sathsara, G. W. C.; Rupasinghe, T. D.; Sumanasena, S. P.
Dyslexia is a well-known reading disorder that involves difficulty in fluent reading, decoding, and processing of words despite adequate intelligence. This causes the reading speed of such patients to be lower than the healthy counterparts, because of slow processing of letters and words. Despite this disorder, a dyslexic person can be trained to read at normal speed. The literature has mainly described manual methods and some technical improvements can be reported such as the Live scribe smart pen, Dragon Naturally Speaking, Word processors, and Video Games. From literature, it is evident that minimal efforts have been mobilized into the aforementioned focus and there is no way other than the manual method to identify the actual reading speeds, and to improve the speed according to the ability of a particular person. Thus, this study produces a novel Machine Learning-based (ML) algorithmic application, which allows customization on the reading speed based on the capabilities of patients, using experiment-based approach with real patients. The study is conducted via three phases. In the first phase of the study, reading rate improvement and detection methodologies are reviewed systematically in order to identify important characteristics of dyslexic improvements. Second phase is focused on developing an ML-based algorithm to identify the improvement rate of the dyslexic patients and training them using Tensorflow and Python. In the third phase, the outcome of the ML based algorithm is tested with samples from different clusters (using iterative experiments with real dyslexic patients). This approach improves the reading speed per minute of the dyslexic patients and lays the foundation for future research in the areas of ML, healthcare applications and ML-based training tools.
Applicability of Bluetooth routing ad-hoc networks for efficient communication.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Jayawardena, B.
In the age of Internet of Things, we expect devices other than computers to communicate with similar or different types of devices. These devices have to be designed in a specific way to communicate and achieve a predefined set of objectives. Hence, the devices need to be aware of with whom they should communicate and what, with what infrastructure and operational environments such as cars, door-locks, refrigerators, health information devices which could create intelligent systems that communicate over the Internet with information/computer systems. On the road, cars may move in a lane one after the other, swiftly engaging in lane changes, slowing down through intersections, accelerating when required, turning left and right after each block. If these vehicles can continuously communicate with each other to exchange status updates on its movement and drivers’ actions, smooth operation of vehicles on roads could become a reality. Cars need to know who is behind them, front of them, and passing them, in order to send messages forward, backward or around each one of them. The study describes two instances (event of braking and road condition of a location) where cars communicate depending on information collected through ad-hoc networks, built upon sharing critical information and a selection of topologies and protocols depending on the objective of the network. The study proposes Bluetooth routing ad-hoc network to provide conceptual framework for dynamic ad-hoc networks where a set of devices can quickly form in a network based on their relative position, continue to maintain the network as new nodes join and leave, and disband once the objective of the network is accomplished. Specialty of this situation is that each node should know who are directly nearby or next to them, and from which direction, in order to communicate specific messages, and when required, a node should be able to reach a group of nodes in a given direction, but out of direct communication range, through intermediary nodes that route communications. A signal such as Wi-Fi would reach longer distance than Bluetooth, confusing this critical discovery process by reaching irrelevant devices faraway. Currently, this area has not been studied specifically. Concept was validated by having a group of devices arranged in a line, being able to discover each other, communicate with each other based on their relative physical positon in the group, and pass simple messages between them. Bluetooth communication uses low power radio signals in a limited range, compared to strong Wi-Fi signals that travel longer distances. Bluetooth ad-hoc routing networks can handle discovery and peer negotiations efficiently and even let stronger, long-distanced Wi-Fi signals make communication between the nodes where required, based on the established Bluetooth ad-hoc network.
Applicability of virtual billing on smartphone based applications for paper waste reduction.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Dissanayake, C.; Peiris, P.; Senevirathne, D.; Wijesooriya, K.; Rupasinghe, T. D.; Liyanaarachchi, N.
The reception of a printed bill has been in global use as the proof of a transaction. Originating as a handwritten bill, the transaction billing has evolved with the advent of printers and computers, and are now an indispensable part of Point – of – Sales systems (POS). However, with the rapid expansion of business entities as well as the increase of wants of consumers, conventional billing consumes large volumes of paper, even in an organizational basis. Most of the bills generated as such are immediately disposed after an initial inspection. Hence, the paper used for billing has a very short usable lifespan and the paper along with the ink become waste. With the rapid advent of the smartphone providing an internet connected handheld portable computational device for the public, proposition of an internet-based virtual billing system has become timely. Although previous studies have been carried out on implementing virtual billing systems, the potential of smartphone has not been utilized in the practical implementation of such systems. The overarching goal of this study is to reduce reliance on paper for billing work. This outcome of the study aims to develop a virtual or a paperless billing system, with interfaces for the storefront user and consumer user. This virtual bill will directly appear on the smartphone application, which uses an Android operating system. In addition to the reduction of paper usage, this approach will also help the customers keep track on the expenditure for a certain commodity per vendor over a particular time period without manually having to calculate the expenses. The outcomes of this research will evaluate the feasibility of practically implementing such a paperless billing system in the context of Sri Lankan business entities.
Application of Markov theory for inventory and cost analysis: Case study for tyre re-treading in automobile company.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Helarathna, N. B.; Wijayanayake, A.
Tyre re-treading is a major value adding process in Sri Lankan rubber and tyre industry as it is focused on repairing, refurbishing and remanufacturing of used tyres’ carcass by attaching new tread on the outer layer. The tyre repairing methods reduce the tyre disposal and enhances the recycling process to earn profits while making the company efficient in environmental performance. The process’ complexity is much higher than traditional manufacturing process as it changes frequently based on the quality of the used tyre. Therefore, it requires close monitoring in order to ensure that the output is error-free to meet the customer expectation in an economical way. Identified key processes in the tyre re-treading department are initial inspection, buffing, tread preparation and building, curing and final inspection which are followed respectively. These are considered as different workstations in the tyre re-treading process. At the end of the process, if the product is in an acceptable quality level, then it is dispatched to the customer, and if not, then the product is sent for re-rework or considered as a defect /rejected product. It is experienced that there are many products fall into the re-rework category causing higher inventory in every workstation and creating unnecessary work order complications and delivery backorders. Also, the processes which are not properly scrutinized incur unexpected raw material, labour and machinery consumption which finally become a huge cost to the company. Since there is no proper mechanism to identify the number of items sent for reverse operations or re-reworks, there is no way to incorporate these things in pricing strategy. Therefore, the unexpected re-rework at each station is not counted for bill of material (BOM) generated through the enterprise resource planning (ERP) system and the additional cost is borne by the company. Therefore, this research is to be conducted to find solutions for the above issues relevant to tyre re-treading. Each workstation is considered as different states in the Markov process as a tyre at any stage can be reversed back to any workstation for the process of re-work and try to compute the number of units move from one stage to the other stage and finally, it moves to the absorbing stage. Application of steady state vector in Markov Theory enables the calculation of the probability of products which will be accepted or rejected in the long run. The transition matrix also enables us to identify the number of items in the reverse operations. Identification of number of products for rework supports not only to manage additional required resources, but also to calculate the relevant cost. This facilitates to compute the actual cost relevant to re-treading into account and enables to incorporate that to the Bill of Material. All these applications eventually increase the efficiency of the tyre re-treading process while reducing the cost borne by the company on re-rework. The research is in the conceptual stage and yet to find the results.
Approximate analytical solution to the time-fractional nonlinear Schrodinger equation through the Sumudu decomposition method.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Mathanaranjan, T.; Himalini, K.
The time-fractional nonlinear Schrodinger equation has the following form:.... where dV is the trapping potential and d is a real constant. The physical model of above equation and its generalized forms arise in various areas of physics, including quantum mechanics, nonlinear optics, plasma physics and superconductivity. Exact solutions of most of the fractional nonlinear Schrodinger equations cannot be found easily. Therefore, analytical and numerical methods have been used in the literature. Some of the analytical methods for solving nonlinear problems include the Adomian decomposition method, Variational iteration method and Homotopy analysis method. In this study, we use the Sumudu decomposition method to construct the approximate analytical solutions of the time-fractional nonlinear Schrodinger equations with zero and nonzero trapping potentials. The Sumudu decomposition method is a combined form of the Sumudu transform and the Adomian decomposition method. The fractional derivatives are defined in the Caputo sense. The exact solutions of some nonlinear Schrodinger equations are given as a special case of our approximate analytical solutions. The computations show that the described method is easy to apply, and it needs smaller size of computation as compared to the aforementioned existing methods. Further, the solutions are derived in a convergent series form which shows the effectiveness of the method for solving a wide variety of nonlinear fractional differential equations.
Assessment of environmental and economic impacts of mangrove deforestation in Vidataltivu lagoon, Sri Lanka.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Marynathan, E.; Sosai, A. S.; Wickramasinghe, W. M. S.; Jayasinghe, G. Y.
Mangroves are unique plants that grow in specific topographic locations under special conditions. Most mangrove ecosystems are under threat because of human interventions. Since Sri Lanka is an island, the mangrove extent is high compared to other countries in the world. The study was aimed at assessing the environmental impact of mangrove deforestation, the effect of mangrove destruction on the economic status of local residents and the degree of awareness about mangroves in the nearby community. The researched location in Vidataltivu has optimal conditions for mangrove ecosystems along with fresh waterfronts entering the sea water. The area selected had 600 families and 90% of them were fishermen. A questionnaire survey was conducted using the stratified random sampling technique for 50 fishermen from Vidataltivu. According to the study 93% of the people had awareness on the damages, causes, human interaction, species diversity and the importance of mangroves to the economy of the community. 36% of the fishermen engaged in fishing for their freedom, 24% of them do not have any alternatives. However, the research has shown that the displacement of people from other parts of the Northern Province had increased the population in this area resulting in excessive consumption of mangroves for various needs. The younger generation (40%) of Vidataltivu has the awareness, but the feel of responsibility is absent as 25% people do not bother about the environment. Ninety two percent people have the basic awareness about mangroves but they do not want to take responsibility. The analysis of data shows a lack of passion for prevention of mangrove destruction. Ninety percent of the people stated that the destruction of mangroves cause a problem to the ecosystem and 92% people also acknowledge that mangrove destruction is one of the major reasons for why the quantity of species has gone down. They also believe that if the mangroves were not destroyed, they must have had a better yield in their fishing nets. However, contradictorily and surprisingly, 78% of them do not want to feel that they were responsible, and are still causing the destruction of most of these mangroves. Therefore, in conclusion this research makes several suggestions such as enabling community participation on mangrove protection and restoration, encouraging youngsters in the area as well as identifying leaders and focus groups within the peripheral community to be trained and motivated towards environmental protection together with enforcement of self-awareness. Eventually, this will lead to a protected mangrove ecosystem in Vidataltivu lagoon in future.
Assessment of polycyclic aromatic hydrocarbons and heavy metals in the vicinity of an oil refinery in Sri Lanka using moss as a bioindicator.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Nirmani, L. P. T.; Deeyamulla, M. P.
Polyaromatic hydrocarbons (PAHs) and heavy metals are toxic compounds emitted from various anthropogenic sources and have a great effect on the human health as well as on the environment. Population living closer to the vicinity of an oil refinery may be at a greater risk of exposure to PAHs through inhalation, ingestion, and direct contact with the contaminated media. Atmospheric deposition of pollutants occur through both wet and dry deposition. Biomonitoring agent and passive monitoring technique were used in this study to evaluate heavy metal and PAH content in moss (Hyophila Involuta) collected from 30 sampling sites around the Sapugaskanda oil refinery with a 5 km radii. Sample collection was carried out in two separate days in September 2016. This study aimed to obtain a possible correlation between the atmospheric deposition of heavy metals and radial distribution pattern using epiphyte mosses collected from each sites. 16 PAHs were identified and quantified using High Performance Liquid Chromatography (HPLC). Bioaccumulation ability of seven heavy metals (Cr, Ni, Cd, Cu, Pb, Fe and Zn) were evaluated by Ion coupled plasma mass spectroscopy (ICP – MS). Contamination factor (CF) and Pollution loading index (PLI) were determined with reference to the background heavy metal concentration values. Maximum heavy metal accumulation was observed in a 2 km radii from the oil refinery. All the sampling sites showed CF>1 except for heavy metals Cr and Cd in few sampling sites. Pollution loading index for each radius showed a higher value with reference to the background levels. Low molecular weight (LMW) PAHs move away from the source (Sapugaskanda refinery) and high molecular weight (HMW) PAHs deposit near the emission source. Total concentration of carcinogenic PAHs varied from 0.25 to 13.75 ng/g. According to the study, total PAHs deposition observed around the vicinity of the oil refinery was in the range of 20 – 4398 ng/g. Due to the similar pollution sources, PAHs have often been found to coexist with environmental pollutants including heavy metals. Correlation studies were carried out statistically. There was a positive correlation between the Fe with Low molecular weight Polyaromatic hydrocarbons (LMW PAH) and High molecular weight polyaromatic hydrocarbons (HMW PAH) (p< 0.05). There were few correlations among several metals. Fe showed a positive correlation with metals such as Ni, Cu and Cd whereas Ni showed positive correlation with Cu and Cd. There was no significant correlation among other metals and PAHs. (p> 0.05).
Black holes as boson stars.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Katugampala, K. D. W. J.; De Silva, L. N. K.
Kaup (1968) had shown that spin zero bosons could form stable stars. However, there had been no interest in these stars until the Higgs boson was discovered in 2012. Now there is renewed interest in boson stars. Clark (2017) in an article “holy moley” published in the New Scientist (15th July) considers boson stars and black holes as two different types of objects. As far as black holes are considered it can only be said that the matter collapses in to a singularity. Boson stars on the other hand are made of bosons. The above article considers black holes and boson stars to be two different kinds leading to same observations with respect to certain objects. However, they could be the same with black holes constituting bosons of zero mass. In this paper it is suggested that some stars, may be most stars, constitute ordinary matter, some may constitute fermions and bosons, while some others are boson stars. It is not ruled out that some stars could be made of bosons of zero mass such as gluons and/or gravitons. Some stars could be made of bosons including photons, as stars with photons only have been ruled out. de Silva (1970) had considered time like geodesics in the Schwarzschild metric and found that the energy of a particle of rest mass m0 at a coordinate distance r can be written as m0kc2 where and u being the velocity of the particle in the local frame at rest with respect to the frame at infinity. In recent research we have found that the rest mass of a particle in a rest frame, called the local rest frame at coordinate distance r could be considered as m0 (1-2M/r)1/2 in a Schwarzschild metric, where m0 is the rest mass of the particle at infinity and M is the Schwarzschild mass of the central object. The rest mass of the particle in the local rest frame decreases, and ends up as zero as the particle enters the singularity with velocity. It implies that black holes in a Schwarzschild metric could be considered as objects made of bosons with zero mass and observed at large distances with non zero Schwarzschild mass .
Business transformation through technology adoption: Special reference to rice millers in Eastern Province, Sri Lanka.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Athambawa, S.; Wickramarachchi, A. P. R.; Puspakumara, C.
The objective of this study is to examine the transformation of business organizations in the agricultural sector in the conflict-affected provinces in the post-conflict period facilitated through the adoption of new technologies. While the opportunities for transformation and growth have increased manifold, the agri-based industries, especially the rice producing sector in the province has not shown many signs of exploiting these opportunities to their potential. Therefore, this study focuses on the rice production business in the Eastern Province. Technologies can play a major role on transforming any businesses, but that entails technology adoption at the right time in the right manner. Through literature factors that contribute to the adoption of technologies leading to business transformation were identified. In order to systematically investigate the existing technology adoption gaps in the region, a comprehensive questionnaire survey was carried out among a large sample of rice millers in the Eastern Province (EP). Then a similar study was carried out with selected millers in the North Central Province (NCP) which possesses a well-developed rice production industry in order to benchmark the performance of the Eastern Province. To select a sample, categorical variables “output capacity” was used for stratification. The sample for the study was selected from each stratum using a simple random sampling technique. Analysis of the data revealed that all factors had positive relationships with technology adoption in the way of transformation. However, the results in the EP indicate that existing set up is inadequately arranged for rapid transformation. The results of a bench marked study showed rice millers in NCP are in a better position when compared to EP in relation to business transformation through technology adoption. Majorities of the Eastern millers have adopted with a moderate level of technology component and capability adoption. In contrast, the benchmarked millers were at high levels of adoption in all components of technology adoption factors. These higher adoption levels led to higher transformation of the benchmarked millers. So, the researcher concludes that the North Central province millers proved that they have more concern on influencing factors, adopted accordingly for the transformation. Further, it was observed that transformation can be achieved through redesigning organizational structure, process, human resources management practices, technology, and changing the organization’s culture. Further, a strong emphasis is to be placed upon a network-based approach with the close cooperation between, owner/managers, government support programmes, and policies.
Cardio forecast: A multi criteria weighted voting ensemble model for the prediction of cardiovascular disease level.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Kitchilan, F. Z.; Samankula, W. G. D. M.
Computational intelligence and data mining in medical domain involve the discovery of unknown patterns and useful knowledge from massive sets of healthcare data. Different machine learning algorithms and statistical analysis tools perform diagnostic procedures. This research presents an intelligent medical knowledge driven approach for the prognosis of heart disease using a weighted voting ensemble classifier. The proposed ensemble classifier overcomes the limitations of single and hybrid data mining techniques by combining outcomes of three heterogeneous classifiers, namely Gaussian Naïve Bayes, Extra Tress and Ada Boost. The clinical data was obtained from processed Cleveland heart disease data set at UCI (University of California, Irvine) Machine Learning Repository. Different pre-processing techniques are used to clean data. There are thirteen (13) dependent attributes and one (1) independent attribute for the prediction in heart disease dataset. This study executes as quantitative research and many related works on data mining and heart disease reviewed and analyzed methodically to get a deep insight of the field. This study is based on statistics and numeric, therefore the research is quantifiable and various relations found between clinical data features. The main scope of study is to enhance the overall accuracy of cardiovascular disease prediction. The original dataset holds predictable attributes ranging from 0 to 4, a healthy heart beginning from 0 to a severely unhealthy heart at 4. In the analysis, the multiclass label changed to binary class. The predicted class either 0 or 1, which means the heart is either 0 ‘negative heart disease’ or 1 ‘positive heart disease’. K-fold cross validation technique is used to evaluate the performance of a proposed ensemble model. The weighted voting ensemble classifier carries out high categorization and diagnosis accuracy by enhancing several performance metrics to a reasonable margin when comparing to other individual and ensemble classifiers. It is obvious from the outcomes that the proposed voting classifier deals with all types of attributes and outperforms the highest accuracy of 92.11%, F1 score 91.89%, precision 92.24% and recall 92.47%. For the proper conclusion for this research to be applied clinically, it requires to further elaborate with the aid of professionals in both cardiac and machine learning domains.
A census of diurnal primates in the villages located between Labugama-Kalatuwawa and Indikada forest reserves in Colombo District of Sri Lanka.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Panagoda, P.A.B.G.; Weerasinghe, V.P.A.
The diurnal primate populations which inhabit the villages, located between Labugama-Kalatuwawa and Indikada Forest Reserves in Colombo District of Sri Lanka, has a high conservation value due to the presence of critically endangered Semnophithecus vetulus nestor (Western purple-faced langur). In addition, these diurnal primate populations consisting of S. vetulus nestor and Macaca sinica (Toque macaque have caused many human-monkey conflict incidents within the area. No studies have assessed the local populations of diurnal primates within this area in spite of its importance in both above perspectives: conservation and conflict. Therefore, this study was aimed to assess the relative density and group size of diurnal primates and to statistically compare above two estimations between the two primate species. The census was carried out within a selected stripe of villages located between the two forests. Using reconnaissance walks, five trails (2 km each) were established to represent the study area, with a systematic sampling design. The trails were walked simultaneously, by five independent trained teams each consisting of five persons, in the morning and afternoon on 3rd of December, 2016. In addition, group counts of monkeys were made during 10 opportunistic field visits, from April to December 2016. For each species, the average group size and group and individual encounter rates (as a measure of relative density) were calculated. The group sizes and encounter rates of the two species were then statistically compared using Mann-Whitney U test. Group size of S. vetulus nestor (mean ± SE) was lower (4.46 ± 0.40 individuals) than that of M. sinica (8.29 ± 2.19 individuals), even though the median group sizes of the two species were not significantly different (p=0.1893). On the other hand, S. vetulus nestor was found to be more abundant in the area compared to M. sinica. The number of encounters of S. vetulus nestor and M. sinica during the census was 10 and 4 respectively. Further, the average group encounter rates (mean ± SE) of S. vetulus nestor and M. sinica, were 0.95 ± 0.31 and 0.33 ± 0.23 respectively (no. of groups/km) whereas the average individual encounter rates (mean ± SE) of S. vetulus nestor and M. sinica, were 4.23 ± 1.38 and 2.71 ± 1.89 (no. of individuals/km) respectively. However, no significant difference was found between the median group (p=0.470) and individual (p=0.4647) encounter rates of the two species. Yet, the higher abundance of S. vetulus nestor over M. sinica, could also be observed during the opportunistic observations made throughout the whole study period (opportunistic group encounters; 22 for S. vetulus nestor and 9 for M. sinica). The reliability of the results can further be improved by censusing at different times of the year. As this study sets a baseline, future studies are recommended to identify any growth or decline of this crucial population of primates.
A class of s-step non-linear iteration scheme based on projection method for s-stage Runge-Kutta method.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Kajanthan, S.; Vigneswaran, R.
A variety of linear iteration schemes with reduced linear algebra costs have been proposed to solve the non-linear equations arising in the implementation of implicit Runge-Kutta methods as an alternative to the modified Newton iteration scheme. In this paper, a class of s-step non-linear scheme based on projection method is proposed to accelerate the convergence rate of those linear iteration schemes. The s-step scheme is given. where is a scalar, O the zero vector. In this scheme, sequence of numerical solutions is updated after each sub-step is completed. The efficiency of this scheme was examined when it is applied to the linear scalar problem with rapid convergence required for all in the left half complex plane, where is a step size, and obtained the iteration matrix of this scheme. The non-singular matrix Q should be chosen to minimize the maximum of the spectral radius of the iteration matrix over the left half complex plane. For 2-stage Gauss method, upper bound for the spectral radius of the iteration matrix was obtained in the left half complex plane. In this approach, it is difficult to handle the 3-stage Gauss method and 4-stage Gauss methods. We transform the coefficient matrix and the iteration matrix to a block diagonal matrix. The result for s=2 is applied to other methods when s>2. Finally, some numerical experiments are carried out to confirm the obtained theoretical results. Numerical result shows that, the proposed class of non- linear iteration scheme accelerates the convergence rate of the linear iteration scheme that we consider for the comparison in this work. It will be possible to apply the proposed class of non-linear scheme to accelerate the rate of convergence of other linear iteration schemes.
Collaborative model to enhance informal communication within software teams.
(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Perera, H.; Wijayanayake, W. M. J. I.
Communication is undoubtedly one of the key elements of successful modern software development, which directly influence on the coordination and teamwork in managing complex software projects. Many researchers have stated that informal communication plays a major role within a software organization than formal communication to achieve objectives. Majority of the knowledge and information within an organization will transfer through informal ways such as cubical chatting, informal emails, telephone calls etc. Informal communication is considered the most significant portion of communication for a software organization’s internal and external progress. Although most of the previous literature considered formal and informal communication together, to the best of our knowledge, there has been no study which had addressed informal communication in software development extensively. There exist many challenges within a software development team such as difficulties in requirements engineering, poor teamwork, poor sharing of resources etc. due to lack of informal communication. One of the main issues is that the best practices and strategies have not been followed within the informal communication network. Therefore, the main objective of this study is to develop a model to enhance the informal communication within a software team. There can be both horizontal informal communication and vertical informal communication present in an organization, and the employees informally communicating would differ accordingly. Also, the way and the extent of informal communication would differ from co-located software projects to global software projects. Taking these aspects into consideration, initially a survey on literature was conducted and with the use of grounded theory, challenges due to lack of informal communication and the best practices in order to mitigate the challenges were identified. Then an industrial analysis was conducted, and similarly, with the aid of grounded theory the challenges and best practices that were applied to real world companies were identified. A theoretical model to be followed in order to enhance and control the existing informal communication network that was developed by linking the challenges and the best practices that had been identified from both the literature survey and the industrial analysis. Finally, the applicability of the model was computed with a number of interviews that were conducted with the industry experts. The best practices introduced in the theoretical model enhances the software team’s informal communication and mitigates many currently existing challenges associated in requirements engineering, teamwork, task allocation etc. It also helps to effectively share knowledge and resources among the software team and increase the transparency among the software team. Further, it is applicable to any type of software team rather than including both local and global software development.