Research Papers - Department of Electrical and Electronic Engineering
Permanent URI for this collectionhttps://rda.sliit.lk/handle/123456789/679
Browse
110 results
Filters
Advanced Search
Filter by
Settings
Search Results
Publication Embargo A Semi Distributed Approach for Feasible Min-Max Fair Agent-assignment Problem with Privacy Guarantees(IEEE, 2018-03) Weeraddana, P. C; Fischione, C; Xu, Y; Alfonsetti, EIn cyberphysical systems, a relevant problem is assigning agents to slots by distributed decisions capable of preserving an agent's privacy. For example, in future intelligent transportation systems, city-level coordinators may optimally assign cars (the agents) to parking slots depending on the cars' distance to final destinations in order to ensure social fairness and without disclosing or even using the car's destination information. Unfortunately, these assignment problems are combinatorial, whereas traditional solvers are exponentially complex, are not scalable, and do not ensure privacy of the agents' intended destinations. Moreover, no emphasis is placed to optimize the agents' social benefit. In this paper, the aggregate social benefit of the agents is considered by an agent-slot assignment optimization problem whose objective function is the fairness among the agents. Due to the problem's complexity, the problem is solved by an approximate approach based on Lagrange duality theory that enables the development of an iterative semidistributed algorithm. It is shown that the proposed algorithm is gracefully scalable compared to centralized methods, and that it preserves privacy in the sense that an eavesdropper will not be able to discover the destination of any agent during the algorithm iterations. Numerical results illustrate the performance and tradeoff of the proposed algorithm compared to the ideal optimal assignment and a greedy method.Publication Embargo An Overview of Social Engineering in the Context of Information Security(IEEE, 2019-01-31) Kaushalya, T; Randeniya, R. M. R. S. B; Liyanage, SSocial engineering in the context of information security is the exploitation of human psychology to gain access into secure data. Human emotion can act as both a strength and a weakness. When it comes to the world booming with technology, human emotions which are completely unrelated to the matter is made to relate through social engineering. Social engineering employs `traps' to pry on human emotion and its vulnerability, taking advantage of the flaws of human psychology. Information security breaches utilising social engineering techniques are vast, so that social engineering in this context is a topic which could not be neglected. This research paper presents an overview of social engineering attacks and suggested defence mechanisms. An introduction to social engineering attacks are given, with context to the current trends and related vulnerabilities. Main reasons for the spread of social engineering attacks in the current context are also presented. Attack frameworks are presented and defence approaches are proposed at the end.Publication Embargo Management of municipal solid waste open dumps immediately after the collapse: An integrated approach from Meethotamulla open dump, Sri Lanka(Elsevier, 2019-07-15) Jayaweera, M; Gunawardana, B; Gunawardana, M; Karunawardena, A; Dias, V; Thilakasiri, S; Karunarathne, D; Wijeratne, N; Manatunge, J; Dissanayake, J. MMeethotamulla open dump (MOD) of Sri Lanka that has received about 290,000 metric tons of mixed MSW annually collapsed on 14th April 2017 with massive devastation. An integrated approach was attempted to control further collapse with the deployment of drone-assisted and stand-alone instrumentation. The collapsed dump was analyzed for attributes, including contours, heights, wetness, temperature levels, tension cracks, landfill gases, fire, explosion, and asphyxiation hazards with 24-h surveillance after one day of the collapse. The mode of MOD failure was implicated to be deep-seated (rotational) slope failure. A short-term plan, consisting of 12 activities was prepared and successfully implemented. The activities of the short-term plan were carried out at the dumpsite until the water level fluctuations <5 cm, inundation of the toe area receded completely, the horizontal displacement of surface markers <20 mm, lower explosive levels of CH4 and CO less than 5 and 12%, respectively, O2 level improved up to 21%, and temperature variation of the collapsed face <2 °C. The short-term plan was halted when the factor of safety for slope failure of the critical face improved from 0.807 to 1.286 ensuring no signs of a subsequent collapse of the MOD. An early warning system was established in the case of an imminent collapse. This integrated approach, to our knowledge, is the first study instituted, and this holistic management effort could be easily replicated to avoid disasters from slope failures of landfills or open dumps that may occur elsewhere.Publication Embargo Prototype of Radio Frequency Identification Technology Utilization for Monitoring of BTS Room Using of IoT (Internet of Things) System(IEEE, 2019-11-28) Saragih, Y; Kurnia, F. E; Aji, S; Elisabet, A; Roostiani, H. A; Hafeel, A. AThe level of battery theft in the BTS room often occurs. RFID prototype is used to open the BTS room is replacing the conventional key. To improve the BTS room security system, a vibrating sensor is used which is applied to the BTS room door, if anyone wants to break or damage the BTS room door by force then the alarm sounds, and use an ultrasonic sensor to detect whether there is a person or object in front of the BTS room, if a person or object is blocking in front of the BTS shelter ≤100 cm, the alarm will sound continuously. Also, the BTS shelter can be monitored via a smartphone as well as getting notifications both in email, smartphone and in the Blynk application.Publication Embargo Digital Creation of Color Illusion Fabricated by Overlaying Different Colored Translucent Textiles Using Images(IEEE, 2019-12-18) Wijesinghe, A; Seneviratne, L; Abeyratne, SOverlaying different colored textiles which are translucent is a straight forward task to complete physically, in contrast this task is difficult to achieve digitally. Amount of information obtained from an image is limited, which is a major difficulty faced when using images to identify the features of a textile such as color, material, texture, thickness and transparency. An algorithmic approach is taken based on three hypotheses; random superimposing, background replacement and color augmentation. These techniques are based on; color identification, background replacement, random selection, pixel superimposing, color blending and image color augmenting. The algorithms are researched, implemented, experimented in-depth and critically compared. Four algorithms are implemented, two based on randomly superimposing and one each based on background replacement and color augmentation. Background replacement algorithm was hardly able to complete the task effectively, thus is the lowest ranked algorithm. In contrast, randomly superimposing and color augmenting algorithms were capable of carrying out the task successfully. Randomly superimposing costed the least time to complete, but the generated images were unnatural whereas color augmenting produced a perfectly natural image though the color of the final output was inaccurate. Further refining the color prediction algorithm is proposed to develop a more effective system.Publication Embargo A Comparison of Fuzzy Logic Controller and PID Controller for Differential Drive Wall-Following Mobile Robot(IEEE, 2019-12-18) Ratnayake, R. M. N. B; De Silva, S; Rodrigo, C. JThis paper presents a comparison between PID controller and Fuzzy rule based controller of a differentially steered wall following mobile robot. Four different maps, generated using Mapper3 software are used to simulate the robot in MobileSim platform. The code was implemented using C++ language in ARIA development package. The robot simulation is performed with Pioneer P3-DX robot. In this study, the data was collected for each cases such as: left wall following and right wall following. In order to validate the results, maximum of 40 runs were conducted for each map and the results were compared with the illustrated methods.Publication Embargo A case study of Sri Lanka oil price fluctuations and its influencing factors using predictive analytics(IEEE, 2016-12-19) Kandawala, D. S. A; Ramanayake, R. T; Bogahawatte, K. G. L; Mansoor, M. A. M; Wanniarachchi, D. M; Asanka, P. P. G. DOil is one of the most crucial commodity and energy resource that guarantee the evolution of the economy and industry of a country. The price fluctuation of the oil would be the emerging factor to be concerned and discussed generally in political and economic circle in each and every country. In Sri Lanka also the problem would be same when it comes to oil industry and its influencing factors for price fluctuation. This paper provides a comprehensive implementation of data warehousing process for the petroleum industry data set. Based on the data collection, a broad data analysis has been conducted to discover patterns of oil prices and sales variation with respect to the political and economic impact factors of Sri Lanka. Through the analysis, it has proven that the influencing factors would affect to the oil prices and sales accordingly. Furthermore, this aims to present few predictions based on the analysis.Publication Open Access Low Cost Optical Power Meter and Bandwidth Analyser with Wide Dynamic Range(researchgate.net, 2014-12-16) Samarawickrama, Y. C; Thilakumara, R. PFiber optic communication is a booming technology in the field of telecommunication due to the advantages over traditional communication systems. It is a timely requirement to produce optical equipment at low cost and reasonable measurement accuracy. This research is about designing of an optical power meter and analyser that can be used in laboratories for educational experimental purposes and for optical signal power measurements to troubleshoot connectivity of optical links. Analyser measures the bandwidth of a modulated optical signal up to 500MHz.Both power meter and analyser can be used for 850nm, 1310nm and 1550nm optical wavelengths. Photodiodes, Logarithmic conversion amplifiers, Trans impedance amplifiers are the main components used in the design. Integrated power meter and analyser, low cost, reasonable measurement accuracy and data logging capability are outstanding features.Publication Embargo Low cost fiber optic teaching aid with wide dynamic range optical power meter and bandwidth analyzer(IEEE, 2015-04-07) Samarawickrama, Y. C; Thilakumara, R. CFiber optic communication technology is an essential component in any Electrical Engineering curriculum. Unfortunately the expensive fiber optic communication equipment is a major drawback in teaching fiber optics theories and principles especially in the 3 rd world countries. This paper presents a development of a low cost Fiber optic power meter and a bandwidth analyzer to be used in laboratories as a teaching aid. Both power meter and analyzer are designed to operate at 850nm, 1310nm and 1550nm optical wavelengths. Analyzer measures the bandwidth of a modulated optical signal up to 500 MHz. The logarithmic amplifier enhances the power meter dynamic range. The cost of the product is less than 100 US dollars at small scale production and can be further reduced if mass produced.Publication Embargo Multiuser Access in LiFi using OFDMA(IEEE, 2018-10-27) Wijesinghe, S. S; Thilakumara, R. PLight Fidelity (LiFi) is an emerging optical technology for wireless data access in short range communication to complement WiFi, a well-established radio frequency (RF) wireless indoor communication standard. Electromagnetic Pollution, relatively low data bandwidths, multipath interference of the indoor propagation to degrade performance, vulnerability to eavesdropping and susceptibility to security threats are major factors that favors LiFi in place of WiFi. However LiFi being an optical technology imposes great difficulty in implementing multiuser access in the Uplink from the user to router. Using Wavelength Division Multiplexing (WDM) for multiuser access drastically increases the cost and complexity of transceivers. This work presents a novel technique of multiuser access using Orthogonal Frequency Division Multiplexing (OFDM) with single carrier per user, implemented by envelope modulation of optical subcarriers for spatially separated users providing compatibility in uplink and downlink of LiFi standard based on OFDM.