MERCon - 2019
Permanent URI for this collectionhttp://192.248.9.226/handle/123/14700
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- item: Conference-Abstract
- item: Conference-AbstractAchieving value from process intensification through better process control(2019) Udugama, IA; Mansouri, SS; Gernaey, KV; Bayer, C; Young, BRThe continual economic drive to achieve improved process efficiencies has made process integration and intensification a main stay in process industries ranging from petrochemicals to biotechnology. However, from a process control viewpoint these integrated and intensified processes are much harder to control due to complex process dynamics and/or reduced degrees of freedom. As such, in many process industries the realized efficiency gain through integration and intensification is diminished. The objective of this article is to highlight some of the lessons learnt by the authors during their involvement in controlling intensified processes in different process industries. To this end two industrial troubleshooting case studies of a side-draw distillation column and a divided wall column are presented together with actual problems the facilities faced and how the solutions developed enabled them to be remedied within industrial limitations. This is followed by an analysis of the current process integration and intensification drive of dairy and bioprocesses. Finally the lessons learnt in these diverse process industries are summarized and its implication for process control discussed.
- item: Conference-AbstractInfluence of enzyme and chemical pretreatment processes on the colours of banana fibresBalakrishnan, S; Wickramasinghe, GLD; Wijayapala, UGSColour is an important property of textile fibres. The colour of mechanically extracted fibre affects the colour of the fibre textiles products. The focus of this investigation is to compare the colour of different pre-treatment process for banana fibre and evaluate the suitability of the banana fibre treatment methods for dyeing process. Experimental research strategies were used to investigate the colour properties. Ambun (AAA/Cavendish) banana variety was selected for this research study. Treated and mechanically extracted banana fibre samples colour measurement was performed by using a data colour machine 600 spectrophotometer and assessed using CIELAB colour values. This experiment was conducted to the suitability of the banana fibre extraction methods for dyeing process. Results indicate that there is a significant change in colour due to the different treatments achieved higher ΔE values. Treatment of enzyme and 6% H2O2, 2% Na2SiO3, 3% NaOH, combined experiments shows higher ΔE values than the other treatments. The FTIR results show that the removal performance of the lignin component is satisfying after the enzyme and chemical combined treatments of banana fibres.
- item: Conference-AbstractDevelopment of a surface muscle pressure monitoring system for wearable robotic devicesChandrasiri, MDSD; Ranaweera, RKPS; Gopura, RARCMonitoring of muscle activities of human limbs is essential for designing controllers of wearable robotic devices such as prosthetics, orthotics and exoskeletons. Human-robot interaction (HRI) is generally studied to control these devices and ascertain comfort levels of the wearer. Cognitive-HRI (cHRI) and physical-HRI (pHRI) are the two main types of HRI methods identified in literature. Surface electromyography (sEMG) signals of skeletal muscles are commonly used in cHRI methods to identify the motion intentions. However, sEMG signals are sensitive to the environmental conditions such as electric and magnetic disturbances. Alternatively, changes to muscle stiffness and volume are measured in pHRI methods. Accordingly, this paper presents a novel sensory system to detect motions of upper or lower limbs by monitoring surface-muscle pressure (SMP). It is comprised of specially designed ’pressurized-air-pouches’ made of silicone. Experiments were carried out with the developed SMP monitoring system to detect muscles activities during biceps curls. The results were compared against sEMG signals to evaluate the validity of the proposed method. The analysis indicated a strong correlation between the signals measured and verifies the potential of using SMP as an effective muscle activity sensing method.
- item: Conference-AbstractA Hybrid powering mechanism for a transtibial robotic prosthesisSathsara, AKP; Widanage, KND; Nilakshman, S; Ranaweera, RKPS; Gopura, RARCThis paper proposes a hybrid powering mechanism for a unilateral transtibial robotic prosthesis named TRoPHy. The device includes both active and passive actuation methods for plantar flexion/ dorsiflexion while inversion/ eversion is achieved passively. The proposed mechanism uses separate spring systems to vary the ankle stiffness and capture the biomechanical energy for the purpose of controlling plantar flexion and dorsiflexion phases of gait cycle. Here, energy stored during the controlled dorsiflexion phase is released and used for propulsion in the powered plantar flexion phase. The testing of the prosthesis was carried out on an able-bodied person, by using a test-rig to affix the prosthesis in parallel to the shank for mimicking the kinematics of the leg. The resulting ankle kinematic data of the prosthesis provided a 97.3% correlation with the natural human ankle kinematics, implying the viability of applying this mechanism to reproduce the ankle behavior accurately. An analysis of the power balance of the system reveals that 38% of the total power required for the powered plantar flexion phase can be reduced effectively from the proposed energy harvesting mechanism.
- item: Conference-AbstractDevelopment of a robotic manipulator to be used in multirotor aerial vehicleWijayathunga, N; Lalitharatne, T; Chathuranga, D; Jayasekara, BThis research introduces a 3 DOF manipulator which is capable of mounting on top of a multirotor aerial vehicle (MAV). It was developed by considering desirable factors like weight reduction, reachable workspace, minimizing the inertia variation and center of mass variation. Reachable workspace for the developed manipulator was identified by computer simulations. A mathematical relationship between the manipulator movements and the inertia variation was obtained. Manipulator movements deviate the initial center of mass of the aerial manipulator which will differ the dynamics of the overall multirotor manipulation system. Therefore, the relationship for the manipulator center of mass variation was obtained with respect to a given general cubic polynomial trajectory. Hence, designing a controller for the overall aerial manipulation can be done while considering the center of mass and inertia variation of the manipulator. This approach will be more effective in disturbance compensation of the aerial vehicle.
- item: Conference-AbstractExtraction and characterization of Nano Crystalline Cellulose (NCC) From Sri Lankan agricultural wasteWickramasinghe, WAWIC; Lasitha, DS; Samarasekara, AMPB; Amarasinghe, DAS; Karunanayake, LIn this research synthesis and characterization of cellulose and nano cellulose and process run under several conditions to obtain parameters which are belongs to optimizing. Cellulose was extracted from BG 352 rice straw using de-waxing, delignification, hemicellulose and silica removal treatment. Extracted cellulose was characterized by Fourier transform infrared spectroscopic techniques (FTIR). SEM image showed that isolated cellulose fibers with diameter ranging from 2-8μm and yield of extracted cellulose are around 21%. Nanocellulose is the material at least one dimension in the nano meter range. The cellulose contains some amorphous regions as well as crystalline regions and by treating some strong acid such as sulfuric to broken up the cellulose from amorphous region. The resultant product is nanocellulose. Nano crystalline cellulose can be obtained from plant matter which comprises nano sized cellulose material. Nano crystalline cellulose synthesis was followed using cellulose by acid hydrolysis, quenching, centrifugation, dialysis, sonication, freeze drying process in this research. So locally available rice straw is a source to synthesize the nano crystalline cellulose.
- item: Conference-AbstractDetection and estimation of damage in framed structures using modal dataDe Silva, WARK; Lewangamage, CS; Jayasinghe, MTRThe inevitable ageing and degradation of buildings and the structural failures that follow, have ignited a need for early prognosis of probable structural failures so that proactive measures can be undertaken. Hence, one of the important steps of structural health monitoring (SHM) process is the detection of damage location and estimation of damage severity. Modal data can be effectively used for this purpose owing to their sole dependency on mechanical characteristics of a structure. This study presents a damage detection methodology based on mode shape derivatives such as mode shape slope (MSS) and mode shape curvature (MSC) for a symmetric experimental steel frame model. Furthermore, an extended parametric analysis has been performed using a calibrated finite element model to investigate damage localization and quantify severity. The study provides key conclusions about the effect of boundaries on the damage detection method for the steel frame model. Furthermore, damage detection using MSC is identified to be more sensitive as opposed to MSS method.
- item: Conference-AbstractBeacon placement algorithm for hybrid indoor positioning with Wi-Fi and bluetooth low energyNuradha, T; Gnanarathne, I; Perera, L; Denipitiyage, D; Dias, DIndoor positioning by wireless means is of significant interest in a wide range of applications; Wi-Fi and Bluetooth Low Energy (BLE) are popular candidate wireless technologies for this. We present a novel BLE beacon placement algorithm that complements existingWi-Fi infrastructure in a hybridWi-Fi/BLE positioning system. Composite signal strength measurements thus obtained, are used to derive machine learning models for location estimation. Our results show that positioning estimates at tablelevel granularity (0.9 m 1.8 m) in a computer laboratory can be achieved with 97% accuracy. This is an improvement of 20% and 30% compared to Wi-Fi and BLE only techniques respectively.
- item: Conference-AbstractACTSEA : annotated corpus for Tamil & Sinhala emotion analysisJenarthanan, R; Senarath, Y; Thayasivam, UThe purpose of text emotion analysis is to detect and recognize the classification of feeling expressed in text. In recent years, there has been an increase in text emotion analysis studies for English language since data were abundant. Due to the growth of social media large amount data are now available for regional languages such as Tamil and Sinhala as well. However, these languages lack necessary annotated corpus for many NLP tasks including emotion analysis. In this paper, we present our scalable semi-automatic approach to create an annotated corpus named ACTSEA for Tamil and Sinhala to support emotion analysis. Alongside, our analysis on a sample of the produced data and the useful findings are presented for the low resourced NLP community to benefit. For ACTSEA, data were gathered from twitter platform and annotated manually after cleaning. We collected 600280 (Tamil) and 318308 (Sinhala) tweets in total which makes our corpus largest data collection which is currently available for these languages.
- item: Conference-AbstractReal-Time FPGA-Based multi-beam directional sensing of 2.4 GHz ISM RF sourcesPulipatI, S; Ariyarathna, V; Edussooriya, CUS; Wijenayake, C; Wang, X; Madanayake, AA real-time directional sensing system is proposed for 2:4 GHz ISM band by exploiting the concept of spatiotemporal spectral white spaces. The proposed system consists of a 16-element patch antenna array, an FFT-based multi-beam beamformer and an energy detector. Our system operates at the baseband with quadrature sampling. Furthermore, digital architectures for two energy detectors that employ integrate-anddump circuits are presented. With the multi-beam beamformer, the first energy detector can be employed to directional sensing and the second can be employed for both directional and spectral sensing of radio frequency sources. The multi-beam beamformer having 16 beams and the energy detectors are implemented on a ROACH-2 based FPGA system with a 160 MHz clock. With an 8-point temporal FFT, the second energy detector provides approximately 20 MHz bandwidth per temporal FFTbin. Preliminary experimental measurements obtained with Wi- Fi devices and the first energy detector verify the proof-of-concept directional sensing of the proposed system.
- item: Conference-AbstractEffect of the shape of the solid insulators on creeping discharge propagation under AC voltagesEdiriweera, S; Jayarathna, P; Samarasinghe, R; Lucas, RThis paper studies the use of circular and square shaped solid insulators on creeping discharge propagation over solid/liquid dielectric interfaces under AC voltages. A point-plane electrode arrangement based test apparatus is used to initiate creeping discharges over solid/liquid interfaces and the discharge propagation is captured using a camera. Two shapes of solid material samples are used to analyze the effect of using different shaped dielectric samples for the creeping propagation under AC voltages. Two types of solid materials, glass and acrylic, immersed in copra coconut oil are tested. Discharge length of the discharge patterns and the fractal dimension calculated by box counting method are used to explain the effect of square shaped and circular shaped dielectric samples for the morphology of creeping discharges. Results show that the shape of the solid dielectric material does not have a significant effect on the discharge length, fractal dimension and the shape of the discharge pattern.
- item: Conference-AbstractAerial Image matching based relative localization of a UAV in urban environmentsChathuranga, TS; Munasinghe, RThis paper presents a method for localizing an Unmanned Aerial Vehicle (UAV) using geo-referenced aerial images, in case of GPS failure. When flying in urban environments in low altitudes the inaccurate GPS localization has become a major problem. The proposed method fuses measurements from inertial sensors and visual odometer and perform image registration process using the images captured by the onboard down looking camera. A pre-built local orthomosaic map with geotagged aerial images is used for the registration. The problem of unreliable matches caused by the dynamic objects is addressed in our approach. The experiment results show that it is possible to localize the UAV in urban environments with a low margin of error by using our method
- item: Conference-AbstractDevelopment of biodegradable packaging materials using Polylactic acid (PLA) and locally extracted starchKaushalya, RANC; Dhanushka, MKDT; Samarasekara, AMPB; Weragoda, VSCThe main objective of this research is to develop a biodegradable packaging material based on Polylactic Acid (PLA) and locally extracted starch. PLA is a biodegradable and bioactive polymer derived from renewable resources. Starch is a biodegradable polymer that can be extracted from different types of plant-based materials such as cassava tubers. Starch was extracted from cassava tubers by crushing, blending and sedimentation processes. The extracted product was characterized by Fourier Transform Infrared Spectroscopic technique (FTIR). Experimental results indicated that 25 wt. % of starch could be extracted from the cassava that was tested. Biodegradable PLA and starch-based blends were prepared by adding starch as the main additive. Soil burial test was performed to analyze the biodegradability of the developed product. Weight loss in starch containing samples gradually increased with time during the soil burial test. Experimental results also indicated that biodegradability of the products increased as the starch content is increased. The mechanical properties such as tensile strength and elongation also decreased as the starch content increased. These results indicated that the addition of starch to PLA is a better method to increase the biodegradability of the PLA –starch blends.
- item: Conference-AbstractStructural analysis of cellulose fibers and rice straw ash derived from Sri Lankan rice strawRatnakumar, A; Samarasekara, AMPB; Amarasinghe, DAS; Karunanayake, LBeing an agricultural country, Sri Lanka generates over eight million metric tonnes of rice straw per annum as a byproduct of the paddy cultivation. Currently rice straw is burnt or ploughed into the field without being converted into a productive output. One such output can be isolating the cellulose fibers from this under-utilized waste material. The availability of rice straw is highly seasonal. In this study, cellulose fibers were extracted from rice straw via a three step chemical purification method straw which yeielded 33.4 ± 0.52 percent. The structure, chemical composition, morphology and thermal properties of rice straw, cellulose and rice straw ash were investigated using laser diffracted particle size analyzer, Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometer, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). FTIR results and SEM images show the removal of lignin and hemicellulose and silica at each step of the isolation process. XRD results exhibit the increase in crystallinity of the fibers. This study reveals that thermal and structural properties have increased after the chemical isolation and purification treatment.
- item: Conference-AbstractAdaptive model predictive control with successive linearization for distillate composition control in batch distillationMendis, P; Wickramasinghe, C; Narayana, M; Bayer, CThis paper investigates the application of adaptive model predictive control (MPC) with successive linearization for the control of top product purity of a batch distillation column. Adaptive MPC with successive linearization can overcome the prediction inaccuracies associated with linearization of highly non-linear and dynamic mathematical model of a batch distillation column, with a lower computational load than nonlinear MPC. A binary mixture of methanol and water was selected to demonstrate the controller development, and its performance was investigated by varying MPC tuning parameters in the MATLAB/Simulink simulation environment. Results indicated that the choice of tuning parameters had a considerable influence on the MPC’s ability to track a constant set-point for the output. With the correct choice of tuning parameters, however, it is possible for the controller to track a constant set-point. The present approach is compared with nonlinear MPC in order to gain a quantitative understanding on accuracy and computational effort.
- item: Conference-AbstractIndustry 4.0 elements and analytics for garment assembly production linesUdayangani, JA; Karunanayaka, IM; Abeysooriya, RPThe world is now witnessing the 4th industrial revolution technology and this is commonly known as Industry 4.0. This study focuses on developing a prototype to demonstrate the smart production line by using Industry 4.0 elements for apparel manufacturing which captures the cycle times of garment assembly operations and balance workloads. As the key elements. Internet of Things (IoT), Cloud Computing and Big data were involved to convert a traditional assembly line to a smart assembly line. The developed prototype allows to capture cycle times of operations and sends those data to a cloud through a wireless network. The data stored in the cloud compute the required arithmetic to draw Yamazumi work balance chart which is dynamically updated without human intervention. A computer client application attached to the cloud act as a decision support system which helps production management to make decisions efficiently. As the special features, the proposed system is also compatible with walking worker production lines where operators are moving from one workstation to another, which also captures actual utilization of the worker at different workstations along the production line which is harder to capture accurately in the actual production scenario.
- item: Conference-AbstractFabrication and characterization of Polypropylene - microcrystalline cellulose based composites with enhanced compatibilityRathnayake, WSM; Karunanayake, L; Samarasekara, AMPB; Amarasinghe, DASThere is a heighten interest on natural fiber reinforced polymer composites to achieve superior, mechanical properties. However, such composites are limited due to the poor compatibility between natural-fiber reinforcement and polymer matrices. An enhanced fiber-polymer interface compatibility was achieved for microcrystalline Cellulose (MCC) and hydrophobic polymer, polypropylene (PP) system using sunflower oil biodiesel (SFEE) based surface treatments. Surface treated MCC was characterized based on their morphology, crystallinity, chemical structure and wettability. The influence of compositional variations of surface modified MCC on composite properties was also studied.
- item: Conference-AbstractSoC based multi-mode battery energy management system for dc microgridsJayasena, KNC; Jayamaha, DKJS; Lidula, NWA; Rajapakse, ADRenewable based DC microgrids are being widely deployed due to its increased efficiency compared to AC networks. An energy storage system helps to cater power flow imbalances due to the intermittent nature of renewable energy sources and varying load conditions. An adaptive Battery Energy Management System (BEMS) to ensure efficient operation of the battery storage system is proposed in this study. The state of charge (SoC) level management is of great importance for the prolong battery life, minimizing the capacity fade and avoiding over draining of the battery storage. Monitoring SoC level, DC bus voltage regulation and ability to provide backup power are the main considerations in designing the proposed BEMS. Performance of the proposed control algorithm was evaluated using PSCAD/EMTDC simulation results, and is presented in this paper.
- item: Conference-AbstractGenerative adversarial networks (GAN) based anomaly detection in industrial software systemsKumarage, T; Ranathunga, S; Kuruppu, C; De Silva, N; Ranawaka, MAdopting an accurate anomaly detection mechanism is crucial for industrial software systems in order to prevent system outages that can deteriorate system availability. However, employing a supervised machine learning technique to detect anomalies in large production scale industrial software systems is highly impractical due to the requirement of annotated data. This raises the need for comprehensive semi-supervised and unsupervised anomaly detection mechanisms. This paper presents the application of Generative Adversarial Network (GAN) based models to detect system anomalies using semi-supervised oneclass learning. We show that the use of a variant of GAN known as bidirectional GAN (BiGAN) gives augmented results when compared to the traditional GAN based anomaly detection, for the selected industrial system. Moreover, the experiments clearly show that the performance of the BiGAN has a direct correlation with the dimensions of the dataset used for training. The BiGAN even tends to outperform the well-established semi-supervised One-class SVM classifier and a prominent generative network for semi-supervised anomaly detection, Variational Autoencoders (VAEs) when the size of the feature space increases.