Search results for: material point method
25191 Size Reduction of Images Using Constraint Optimization Approach for Machine Communications
Authors: Chee Sun Won
Abstract:
This paper presents the size reduction of images for machine-to-machine communications. Here, the salient image regions to be preserved include the image patches of the key-points such as corners and blobs. Based on a saliency image map from the key-points and their image patches, an axis-aligned grid-size optimization is proposed for the reduction of image size. To increase the size-reduction efficiency the aspect ratio constraint is relaxed in the constraint optimization framework. The proposed method yields higher matching accuracy after the size reduction than the conventional content-aware image size-reduction methods.Keywords: image compression, image matching, key-point detection and description, machine-to-machine communication
Procedia PDF Downloads 41825190 Changes in the Properties of Composites Caused by Chemical Treatment of Hemp Hurds
Authors: N. Stevulova, I. Schwarzova
Abstract:
The possibility of using industrial hemp as a source of natural fibers for purpose of construction, mainly for the preparation of lightweight composites based on hemp hurds is described. In this article, an overview of measurement results of important technical parameters (compressive strength, density, thermal conductivity) of composites based on organic filler - chemically modified hemp hurds in three solutions (EDTA, NaOH and Ca(OH)2) and inorganic binder MgO-cement after 7, 28, 60, 90 and 180 days of hardening is given. The results of long-term water storage of 28 days hardened composites at room temperature were investigated. Changes in the properties of composites caused by chemical treatment of hemp material are discussed.Keywords: hemp hurds, chemical modification, lightweight composites, testing material properties
Procedia PDF Downloads 34925189 The Structural and Electrical Properties of Cadmium Implanted Silicon Diodes at Room Temperature
Authors: J. O. Bodunrin, S. J. Moloi
Abstract:
This study reports on the x-ray crystallography (XRD) structure of cadmium-implanted p-type silicon, the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of unimplanted and cadmium-implanted silicon-based diodes. Cadmium was implanted at the energy of 160 KeV to the fluence of 10¹⁵ ion/cm². The results obtained indicate that the diodes were well fabricated, and the introduction of cadmium results in a change in behavior of the diodes from normal exponential to ohmic I-V behavior. The C-V measurements, on the other hand, show that the measured capacitance increased after cadmium doping due to the injected charge carriers. The doping density of the p-Si material and the device's Schottky barrier height was extracted, and the doping density of the undoped p-Si material increased after cadmium doping while the Schottky barrier height reduced. In general, the results obtained here are similar to those obtained on the diodes fabricated on radiation-hard material, indicating that cadmium is a promising metal dopant to improve the radiation hardness of silicon. Thus, this study would assist in adding possible options to improve the radiation hardness of silicon to be used in high energy physics experiments.Keywords: cadmium, capacitance-voltage, current-voltage, high energy physics experiment, x-ray crystallography, XRD
Procedia PDF Downloads 13225188 High-Pressure CO₂ Adsorption Capacity of Selected Unusual Porous Materials and Rocks
Authors: Daniela Rimnacova, Maryna Vorokhta, Martina Svabova
Abstract:
CO₂ adsorption capacity of several materials - waste (power fly ash, slag, carbonized sewage sludge), rocks (Czech Silurian shale, black coal), and carbon (synthesized carbon, activated carbon as a reference material) - were measured on dry samples using a unique hand-made manometric sorption apparatus at a temperature of 45 °C and pressures of up to 7 MPa. The main aim was finding utilization of the waste materials and rocks for removal of the air or water pollutants caused by anthropogenic activities, as well as for the carbon dioxide storage. The equilibrium amount of the adsorbate depends on temperature, gas saturation pressure, porosity, surface area and volume of pores, and last but not least, on the composition of the adsorbents. Given experimental conditions can simulate in-situ situations in the rock bed and can be achieved just by a high-pressure apparatus. The CO₂ excess adsorption capacities ranged from 0.018 mmol/g (ash) to 13.55 mmol/g (synthesized carbon). The synthetized carbon had the highest adsorption capacity among all studied materials as well as the highest price. This material is usually used for the adsorption of specific pollutants. The excess adsorption capacity of activated carbon was 9.19 mmol/g. It is used for water and air cleaning. Ash can be used for chemisorption onto ash particle surfaces or capture of special pollutants. Shale is a potential material for enhanced gas recovery or CO₂ sequestration in-situ. Slag is a potential material for capture of gases with a possibility of the underground gas storage after the adsorption process. The carbonized sewage sludge is quite a good adsorbent for the removal and capture of pollutants, as well as shales or black coal which show an interesting relationship between the price and adsorption capacity.Keywords: adsorption, CO₂, high pressure, porous materials
Procedia PDF Downloads 16125187 Shear Buckling of a Large Pultruded Composite I-Section under Asymmetric Loading
Authors: Jin Y. Park, Jeong Wan Lee
Abstract:
An experimental and analytical research on shear buckling of a comparably large polymer composite I-section is presented. It is known that shear buckling load of a large span composite beam is difficult to determine experimentally. In order to sensitively detect shear buckling of the tested I-section, twenty strain rosettes and eight displacement sensors were applied and attached on the web and flange surfaces. The tested specimen was a pultruded composite beam made of vinylester resin, E-glass, carbon fibers and micro-fillers. Various coupon tests were performed before the shear buckling test to obtain fundamental material properties of the I-section. An asymmetric four-point bending loading scheme was utilized for the shear test. The loading scheme resulted a high shear and almost zeros moment condition at the center of the web panel. The shear buckling load was successfully determined after analyzing the obtained test data from strain rosettes and displacement sensors. An analytical approach was also performed to verify the experimental results and to support the discussed experimental program.Keywords: strain sensor, displacement sensor, shear buckling, polymer composite I-section, asymmetric loading
Procedia PDF Downloads 45225186 Microbial Evaluation of Geophagic and Cosmetic Clays from Southern and Western Nigeria: Potential Natural Nanomaterials
Authors: Bisi-Johnson, Mary A., Hamzart A. Oyelade, Kehinde A. Adediran, Saheed A. Akinola
Abstract:
Geophagic and cosmetic clays are among potential nano-material which occur naturally and are of various forms. The use of these nano-clays is a common practice in both rural and urban areas mostly due to tradition and medicinal reasons. These naturally occurring materials can be valuable sources of nano-material by serving as nano-composites. The need to ascertain the safety of these materials is the motivation for this research. Physical Characterization based on the hue value and microbiological qualities of the nano-clays were carried out. The Microbial analysis of the clay samples showed considerable contamination with both bacteria and fungi with fungal contaminants taking the lead. This observation may not be unlikely due to the ability of fungi species to survive harsher growth conditions than bacteria. 'Atike pupa' showed no bacterial growth. The clay with the largest bacterial count was Calabash chalk (Igbanke), while that with the highest fungal count was 'Eko grey'. The most commonly isolated bacteria in this study were Clostridium spp. and Corynebacterium spp. while fungi included Aspergillus spp. These results are an indication of the need to subject these clay materials to treatments such as heating before consumption or topical usage thereby ascertaining their safety.Keywords: nano-material, clay, microorganism, quality
Procedia PDF Downloads 39625185 Feasibility of Agro Waste-Derived Adsorbent for Colour Removal
Authors: U. P. L. Wijayarathne, P. W. Vidanage, H. K. D. Jayampath, K. W. P. M. Kothalawala
Abstract:
Feasibility of utilizing Empty Bunch (EB) fibre, a solid waste of palm oil extraction process, as an adsorbent is analysed in this study. Empty bunch fibre is generated after the extraction of retained oil in the sterilized and threshed empty fruit bunches. Besides the numerous characteristics of EB fibre, which enable its utilization as a fuel, a bio-composite material, or mulch, EB fibre also shows exceptional characteristics of a good adsorbent. Fixed bed adsorption method is used to study the adsorptivity of EB fibre using a continuous adsorption column with Methyl-blue (1.13ppm) as the feed. Adsorptivity is assumed to be solely dependent on the bed porosity keeping other parameters (feed flow rate, bed height, bed diameter, and operating temperature) constant. Bed porosity is changed by means of compact ratio and the variation of the feed concentration is analysed using a photometric method. Break through curves are plotted at different porosity levels and optimum bed porosity is identified for a given feed stream. Feasibility of using the EB fibre as an inexpensive and an abundant adsorbent in wastewater treatment facilities, where the effluent colour reduction is adamant, is also discussed.Keywords: adsorption, fixed bed, break through time, methylene blue, oil palm fibre
Procedia PDF Downloads 28925184 Stuttering Persistence in Children: Effectiveness of the Psicodizione Method in a Small Italian Cohort
Authors: Corinna Zeli, Silvia Calati, Marco Simeoni, Chiara Comastri
Abstract:
Developmental stuttering affects about 10% of preschool children; although the high percentage of natural recovery, a quarter of them will become an adult who stutters. An effective early intervention should help those children with high persistence risk for the future. The Psicodizione method for early stuttering is an Italian behavior indirect treatment for preschool children who stutter in which method parents act as good guides for communication, modeling their own fluency. In this study, we give a preliminary measure to evaluate the long-term effectiveness of Psicodizione method on stuttering preschool children with a high persistence risk. Among all Italian children treated with the Psicodizione method between 2018 and 2019, we selected 8 kids with at least 3 high risk persistence factors from the Illinois Prediction Criteria proposed by Yairi and Seery. The factors chosen for the selection were: one parent who stutters (1pt mother; 1.5pt father), male gender, ≥ 4 years old at onset; ≥ 12 months from onset of symptoms before treatment. For this study, the families were contacted after an average period of time of 14,7 months (range 3 - 26 months). Parental reports were gathered with a standard online questionnaire in order to obtain data reflecting fluency from a wide range of the children’s life situations. The minimum worthwhile outcome was set at "mild evidence" in a 5 point Likert scale (1 mild evidence- 5 high severity evidence). A second group of 6 children, among those treated with the Piscodizione method, was selected as high potential for spontaneous remission (low persistence risk). The children in this group had to fulfill all the following criteria: female gender, symptoms for less than 12 months (before treatment), age of onset <4 years old, none of the parents with persistent stuttering. At the time of this follow-up, the children were aged 6–9 years, with a mean of 15 months post-treatment. Among the children in the high persistence risk group, 2 (25%) hadn’t had stutter anymore, and 3 (37,5%) had mild stutter based on parental reports. In the low persistency risk group, the children were aged 4–6 years, with a mean of 14 months post-treatment, and 5 (84%) hadn’t had stutter anymore (for the past 16 months on average).62,5% of children at high risk of persistence after Psicodizione treatment showed mild evidence of stutter at most. 75% of parents confirmed a better fluency than before the treatment. The low persistence risk group seemed to be representative of spontaneous recovery. This study’s design could help to better evaluate the success of the proposed interventions for stuttering preschool children and provides a preliminary measure of the effectiveness of the Psicodizione method on high persistence risk children.Keywords: early treatment, fluency, preschool children, stuttering
Procedia PDF Downloads 21725183 The Evolving Customer Experience Management Landscape: A Case Study on the Paper Machine Companies
Authors: Babak Mohajeri, Sen Bao, Timo Nyberg
Abstract:
Customer experience is increasingly the differentiator between successful companies and those who struggle. Currently, customer experiences become more dynamic; and they advance with each interaction between the company and a customer. Every customer conversation and any effort to evolve these conversations would be beneficial and should ultimately result in a positive customer experience. The aim of this paper is to analyze the evolving customer experience management landscape and the relevant challenges and opportunities. A case study on the “paper machine” companies is chosen. Hence, this paper analyzes the challenges and opportunities in customer experience management of paper machine companies for the case of “road to steel”. Road to steel shows the journey of steel from raw material to end product (i.e. paper machine in this paper). ALPHA (Steel company) and BETA (paper machine company), are chosen and their efforts to evolve the customer experiences are investigated. Semi-structured interviews are conducted with experts in those companies to identify the challenges and opportunities of the evolving customer experience management from their point of view. The findings of this paper contribute to the theory and business practices in the realm of the evolving customer experience management landscape.Keywords: Customer Experience Management, Paper Machine , Value Chain Management, Risk Analysis
Procedia PDF Downloads 36225182 A Simple Technique for Centralisation of Distal Femoral Nail to Avoid Anterior Femoral Impingement and Perforation
Authors: P. Panwalkar, K. Veravalli, M. Tofighi, A. Mofidi
Abstract:
Introduction: Anterior femoral perforation or distal anterior nail position is a known complication of femoral nailing specifically in pertrochantric fractures fixed with cephalomedullary nail. This has been attributed to wrong entry point for the femoral nail, nail with large radius of curvature or malreduced fracture. Left alone anterior perforation of femur or abutment of nail on anterior femur will result in pain and risk stress riser at distal femur and periprosthetic fracture. There have been multiple techniques described to avert or correct this problem ranging from using different nail, entry point change, poller screw to deflect the nail position, use of shorter nail or use of curved guidewire or change of nail to ensure a nail with large radius of curvature Methods: We present this technique which we have used in order to centralise the femoral nail either when the nail has been put anteriorly or when the guide wire has been inserted too anteriorly prior to the insertion of the nail. This technique requires the use of femoral reduction spool from the nailing set. This technique was used by eight trainees of different level of experience under supervision. Results: This technique was easily reproducible without any learning curve without a need for opening of fracture site or change in the entry point with three different femoral nailing sets in twenty-five cases. The process took less than 10 minutes even when revising a malpositioned femoral nail. Conclusion: Our technique of using femoral reduction spool is easily reproducible and repeatable technique for avoidance of non-centralised femoral nail insertion and distal anterior perforation of femoral nail.Keywords: femoral fracture, nailing, malposition, surgery
Procedia PDF Downloads 14225181 3D Design of Orthotic Braces and Casts in Medical Applications Using Microsoft Kinect Sensor
Authors: Sanjana S. Mallya, Roshan Arvind Sivakumar
Abstract:
Orthotics is the branch of medicine that deals with the provision and use of artificial casts or braces to alter the biomechanical structure of the limb and provide support for the limb. Custom-made orthoses provide more comfort and can correct issues better than those available over-the-counter. However, they are expensive and require intricate modelling of the limb. Traditional methods of modelling involve creating a plaster of Paris mould of the limb. Lately, CAD/CAM and 3D printing processes have improved the accuracy and reduced the production time. Ordinarily, digital cameras are used to capture the features of the limb from different views to create a 3D model. We propose a system to model the limb using Microsoft Kinect2 sensor. The Kinect can capture RGB and depth frames simultaneously up to 30 fps with sufficient accuracy. The region of interest is captured from three views, each shifted by 90 degrees. The RGB and depth data are fused into a single RGB-D frame. The resolution of the RGB frame is 1920px x 1080px while the resolution of the Depth frame is 512px x 424px. As the resolution of the frames is not equal, RGB pixels are mapped onto the Depth pixels to make sure data is not lost even if the resolution is lower. The resulting RGB-D frames are collected and using the depth coordinates, a three dimensional point cloud is generated for each view of the Kinect sensor. A common reference system was developed to merge the individual point clouds from the Kinect sensors. The reference system consisted of 8 coloured cubes, connected by rods to form a skeleton-cube with the coloured cubes at the corners. For each Kinect, the region of interest is the square formed by the centres of the four cubes facing the Kinect. The point clouds are merged by considering one of the cubes as the origin of a reference system. Depending on the relative distance from each cube, the three dimensional coordinate points from each point cloud is aligned to the reference frame to give a complete point cloud. The RGB data is used to correct for any errors in depth data for the point cloud. A triangular mesh is generated from the point cloud by applying Delaunay triangulation which generates the rough surface of the limb. This technique forms an approximation of the surface of the limb. The mesh is smoothened to obtain a smooth outer layer to give an accurate model of the limb. The model of the limb is used as a base for designing the custom orthotic brace or cast. It is transferred to a CAD/CAM design file to design of the brace above the surface of the limb. The proposed system would be more cost effective than current systems that use MRI or CT scans for generating 3D models and would be quicker than using traditional plaster of Paris cast modelling and the overall setup time is also low. Preliminary results indicate that the accuracy of the Kinect2 is satisfactory to perform modelling.Keywords: 3d scanning, mesh generation, Microsoft kinect, orthotics, registration
Procedia PDF Downloads 19125180 The Development of the Prototype of Bamboo Shading Device
Authors: Nuanwan Tuaycharoen, Wanarat Konisranukul
Abstract:
The main aim of this research was to investigate the prototype of bamboo shading device. There were two objectives of this study. The first objective was to investigate the effect of non-chemical treatments on damage of bamboo shading device by powder-post beetle and fungi. The second aim of this study was to develop a prototype of bamboo shading device. The study of the effect of non-chemical treatments on damage of bamboo shading device by powder-post beetle in laboratory showed that, among seven treatments tested, wood vinegar treatment can protect powder-post beetle better than the original method up to 92.91%. It was also found that wood vinegar treatment can show the best performance in fungi protection and work better than the original method up to 40%. The second experiment was carried out by constructing four bamboo shading devices and installing them on a building for 28 days. All aspects of shading device were investigated in terms of their beauty, durability, and ease of construction and assembly. The final prototype was developed from the lessons drawn from these tested options. In conclusion this study showed the effectiveness of some natural preservatives against insect and fungi damage. It also illustrated the characteristics of the prototype of bamboo shading device that can constructed by rural workers within one week.Keywords: bamboo, shading device, energy conservation, alternative material
Procedia PDF Downloads 37825179 Optimizing Mechanical Behavior of Middle Ear Prosthesis Using Finite Element Method with Material Degradation Functionally Graded Materials in Three Functions
Authors: Khatir Omar, Fekih Sidi Mohamed, Sahli Abderahmene, Benkhettou Abdelkader, Boudjemaa Ismail
Abstract:
Advancements in technology have revolutionized healthcare, with notable impacts on auditory health. This study introduces an approach aimed at optimizing materials for middle ear prostheses to enhance auditory performance. We have developed a finite element (FE) model of the ear incorporating a pure titanium TORP prosthesis, validated against experimental data. Subsequently, we applied the Functionally Graded Materials (FGM) methodology, utilizing linear, exponential, and logarithmic degradation functions to modify prosthesis materials. Biocompatible materials suitable for auditory prostheses, including Stainless Steel, titanium, and Hydroxyapatite, were investigated. The findings indicate that combinations such as Stainless Steel with titanium and Hydroxyapatite offer improved outcomes compared to pure titanium and Hydroxyapatite ceramic in terms of both displacement and stress. Additionally, personalized prostheses tailored to individual patient needs are feasible, underscoring the potential for further advancements in auditory healthcare.Keywords: middle ear, prosthesis, ossicles, FGM, vibration analysis, finite-element method
Procedia PDF Downloads 8625178 Opto-Mechanical Characterization of Aspheric Lenses from the Hybrid Method
Authors: Aliouane Toufik, Hamdi Amine, Bouzid Djamel
Abstract:
Aspheric optical components are an alternative to the use of conventional lenses in the implementation of imaging systems for the visible range. Spherical lenses are capable of producing aberrations. Therefore, they are not able to focus all the light into a single point. Instead, aspherical lenses correct aberrations and provide better resolution even with compact lenses incorporating a small number of lenses. Metrology of these components is very difficult especially when the resolution requirements increase and insufficient or complexity of conventional tools requires the development of specific approaches to characterization. This work is part of the problem existed because the objectives are the study and comparison of different methods used to measure surface rays hybrid aspherical lenses.Keywords: manufacture of lenses, aspherical surface, precision molding, radius of curvature, roughness
Procedia PDF Downloads 46725177 Horizontal Circular Curve Computations Using a Developed Calculator
Authors: Adil Hassabo
Abstract:
In this paper, a horizontal circular curve computations calculator is developed in Microsoft Windows. The developed calculator can be used for determining the necessary information required for setting out horizontal curves. Three methods are applied in the developed program namely: incremental chord method, total chord method, and the coordinates method. Computations of horizontal curves by the developed calculator is faster, easier, accurate, and less subject to errors comparable to the traditional method of calculations. Finally, the results obtained by the traditional method and by the developed calculator are presented for checking the behavior of the developed calculator.Keywords: calculator, circular, computations, curve
Procedia PDF Downloads 16225176 The Distributed Pattern of the Neurovascular Structures under Clavicle to Minimize Structural Injury in Clinical Field: Anatomical Study
Authors: Anna Jeon, Seung-Ho Han, Je-Hun Lee
Abstract:
The aim of this study was to determine the location and distribution pattern of neurovascular structures superior and inferior to the clavicle by detailed dissection. Fifteen adult non-embalmed cadavers with a mean age of 71.5 years were studied. For measurements, the most prominent point of the sternal end of the clavicle (SEC) on anterior view and the most prominent point of the acromial end of the clavicle (AEC) were identified before dissection. A line connecting the SEC and AEC was used as a reference line. The surrounding neurovascular structures were investigated. The supraclavicular nerve was densely distributed at 71.73% on the reference line. Branches of the thoracoacromial artery were located at 76.92%. Branches of subclavian vein were evenly distributed at all sections. The subclavian vein and artery and brachial plexus were located from 31.3% to 57.5%. That area needs caution because major neurovascular structures run underneath the clavicle.Keywords: clavicle, ORIF, neurovascular structure, anatomical study
Procedia PDF Downloads 16625175 Free Vibration Characteristics of Nanoplates with Various Edge Supports Incorporating Surface Free Energy Effects
Authors: Saeid Sahmani
Abstract:
Due to size-dependent behavior of nanostrustures, the classical continuum models are not applicable for the analyses at this submicrion size. Surface stress effect is one of the most important matters which make the nanoscale structures to have different properties compared to the conventional structures due to high surface to volume ratio. In the present study, free vibration characteristics of nanoplates are investigated including surface stress effects. To this end, non-classical plate model based on Gurtin-Murdoch elasticity theory is proposed to evaluate the surface stress effects on the vibrational behavior of nanoplates subjected to different boundary conditions. Generalized differential quadrature (GDQ) method is employed to discretize the governing non-classical differential equations along with various edge supports. Selected numerical results are given to demonstrate the distinction between the behavior of nanoplates predicted by the classical and present non-classical plate models that leads to illustrate the great influence of surface stress effect. It is observed that this influence quite depends on the magnitude of the surface elastic constants which are relevant to the selected material.Keywords: nanomechanics, surface stress, free vibration, GDQ method, small scale effect
Procedia PDF Downloads 35625174 Containment/Penetration Analysis for the Protection of Aircraft Engine External Configuration and Nuclear Power Plant Structures
Authors: Dong Wook Lee, Adrian Mistreanu
Abstract:
The authors have studied a method for analyzing containment and penetration using an explicit nonlinear Finite Element Analysis. This method may be used in the stage of concept design for the protection of external configurations or components of aircraft engines and nuclear power plant structures. This paper consists of the modeling method, the results obtained from the method and the comparison of the results with those calculated from simple analytical method. It shows that the containment capability obtained by proposed method matches well with analytically calculated containment capability.Keywords: computer aided engineering, containment analysis, finite element analysis, impact analysis, penetration analysis
Procedia PDF Downloads 13925173 A Grid Synchronization Method Based On Adaptive Notch Filter for SPV System with Modified MPPT
Authors: Priyanka Chaudhary, M. Rizwan
Abstract:
This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.Keywords: solar photovoltaic systems, MPPT, voltage source converter, grid synchronization technique
Procedia PDF Downloads 59425172 Theoretical Approach to Kinetics of Transient Plasticity of Metals under Irradiation
Authors: Pavlo Selyshchev, Tetiana Didenko
Abstract:
Within the framework of the obstacle radiation hardening and the dislocation climb-glide model a theoretical approach is developed to describe peculiarities of transient plasticity of metal under irradiation. It is considered nonlinear dynamics of accumulation of point defects (vacancies and interstitial atoms). We consider metal under such stress and conditions of irradiation at which creep is determined by dislocation motion: dislocations climb obstacles and glide between obstacles. It is shown that the rivalry between vacancy and interstitial fluxes to dislocation leads to fractures of plasticity time dependence. Simulation and analysis of this phenomenon are performed. Qualitatively different regimes of transient plasticity under irradiation are found. The fracture time is obtained. The theoretical results are compared with the experimental ones.Keywords: climb and glide of dislocations, fractures of transient plasticity, irradiation, non-linear feed-back, point defects
Procedia PDF Downloads 20225171 The Construct of Assessment Instrument for Value, Attitude and Professionalism among Students Faculty of Sports Science and Coaching
Authors: Ahmad Hashim, Thariq Khan Azizuddin Khan, Zulakbal Abd Karim, Nohazira Abdul Karim
Abstract:
This research aims to obtain the validity and reliability of a survey instrument to evaluate the values, attitudes, and professionalism of sports science students, from the Faculty of Sports Science and Coaching, Universiti Pendidikan Sultan Idris (UPSI). It is a survey which is divided into two components namely first; moral, self-esteem, proactive, self-reliant and voluntary and second; ethics and professionalism. Development of the survey instrument is based on the Malaysian Education Development Plan, Higher Education Malaysia. There are 50 items prepared based on the five-point Likert scale which were tested at the pilot test level. It involved 212 research subjects selected based on random sampling. In addition, the research method applied is in the form of pre-experimental one group pre-test-post-test. Results of the analysis showed that overall field expert validity is r = .89, while the Cronbach alpha reliability correlation value of outdoor education instrument evaluation survey is r = .85. Next, this survey was tested again for construct validity using the factor analysis method for statistical analysis which would validate each item tested was supposed to be in the right component. From the analysis, results show that Bartlett's test is significant p < .05 and Kaiser-Meyer-Olkin index range is r = .87. The result showed 39 survey items are produced out of 50 items of the survey based on this factor analysis method. Research has shown that the survey instrument developed is valid and reliable to be used for the Faculty of Sports Sciences and Coaching, UPSI.Keywords: values, attitudes, professionalism, ethics, professionalism
Procedia PDF Downloads 19125170 Repair and Strengthening of Plain and FRC Shear Deficient Beams Using Externally Bonded CFRP Sheets
Authors: H. S. S. Abou El-Mal, H. E. M. Sallam
Abstract:
This paper presents experimental and analytical study on the behavior of repaired and strengthened shear critical RC beams using externally bonded CFRP bi-directional fabrics. The use of CFRP sheets to repair or strengthen RC beams has been repetitively studied and proven feasible. However, the use of combined repair techniques and applying that method to both plain and FRC beams can maximize the shear capacity of RC shear deficient beams. A total of twelve slender beams were tested under four-point bending. The test parameters included CFRP layout, number of layers and fiber direction, injecting cracks before applying repairing sheets, enhancing the flexural capacity to differentiate between shear repair and strengthening techniques, and concrete matrix types. The findings revealed that applying CFRP sheets increased the overall shear capacity, the amount and orientation of wrapping is of prime importance in both repairing and strengthening, CFRP wrapping could change the failure mode from shear to flexural shear, the use of crack injection combined to CFRP wrapping further improved the shear capacity while, applying the previous method to FRC beams enhanced both shear capacity and failure ductility. Acceptable agreement was found between predicted shear capacities using the Canadian code and the experimental results of the current study.Keywords: CFRP, FRC, repair, shear strengthening
Procedia PDF Downloads 34925169 Utilizing Laser Cutting Method in Men's' Custom-Made Casualwear
Authors: M A. Habit, S. A. Syed-Sahil, A. Bahari
Abstract:
Abstract—Laser cutting is a method of manufacturing process that uses laser in order to cut materials. It provides and ensures extreme accuracy which has a clean cut effect, CO2 laser dominate this application due to their good- quality beam combined with high output power. It comes with a small scale and it has a limitation in cutting sizes of materials, therefore it is more appropriate for custom- made products. The same laser cutting machine is also capable in cutting fine material such as fine silk, cotton, leather, polyester, etc. Lack of explorations and knowledge besides being unaware about this technology had caused many of the designers not to use this laser cutting method in their collections. The objectives of this study are: 1) To identify the potential of laser cutting technique in Custom-Made Garments for men’s casual wear: 2) To experiment the laser cutting technique in custom made garments: 3) To offer guidelines and formula for men’s custom- made casualwear designs with aesthetic value. In order to achieve the objectives, this research has been conducted by using mixed methods which are interviews with two (2) local experts in the apparel manufacturing industries and interviews via telephone with five (5) local respondents who are local emerging fashion designers, the questionnaires were distributed to one hundred (100) respondents around Klang Valley, in order to gain the information about their understanding and awareness regarding laser cutting technology. The experiment was conducted by using natural and man- made fibers. As a conclusion, all of the objectives had been achieved in producing custom-made men’s casualwear and with the production of these attires it will help to educate and enhance the innovation in fine technology. Therefore, there will be a good linkage and collaboration between the design experts and the manufacturing companies.Keywords: custom-made, fashion, laser cut, men’s wear
Procedia PDF Downloads 44125168 On Tarski’s Type Theorems for L-Fuzzy Isotone and L-Fuzzy Relatively Isotone Maps on L-Complete Propelattices
Authors: František Včelař, Zuzana Pátíková
Abstract:
Recently a new type of very general relational structures, the so called (L-)complete propelattices, was introduced. These significantly generalize complete lattices and completely lattice L-ordered sets, because they do not assume the technically very strong property of transitivity. For these structures also the main part of the original Tarski’s fixed point theorem holds for (L-fuzzy) isotone maps, i.e., the part which concerns the existence of fixed points and the structure of their set. In this paper, fundamental properties of (L-)complete propelattices are recalled and the so called L-fuzzy relatively isotone maps are introduced. For these maps it is proved that they also have fixed points in L-complete propelattices, even if their set does not have to be of an awaited analogous structure of a complete propelattice.Keywords: fixed point, L-complete propelattice, L-fuzzy (relatively) isotone map, residuated lattice, transitivity
Procedia PDF Downloads 27925167 A Review on the Outlook of the Circular Economy in the Automotive Industry
Abstract:
The relationship of the automotive industry with raw material supply is a major challenge and presents obstacles. Automobiles are ones of the most complex products using a large variety of materials. Safety, eco-friendliness and comfort requirements, physical, chemical and economic limitations set the framework in which this industry continuously optimizes the efficient and responsible use of resources. The concept of circular economy covers the issues of waste generation, resource scarcity and economic advantages. However, circularity is already known for the automobile industry – several efforts are done to foster material reuse, product remanufacturing and recycling. The aim of this study is to give an overview on how the producers comply with the growing demands on one hand, and gain efficiency and increase profitability on the other hand from circular economy.Keywords: automotive industry, circular economy, international requirements, natural resources
Procedia PDF Downloads 32725166 Characterization of Porosity and Flow in Solid Oxide Fuel Cell with 3D Focused Ion Beam Serial Slicing
Authors: Daniel Phifer, Anna Prokhodtseva
Abstract:
DualBeam (FIB-SEM) has long been the technology of choice to sub-sample and characterize materials at site-specific locations which are difficult or impossible to extract by conventional embedding/polishing methods. Whereas Ga based FIB provides excellent resolution and enables precise material removal, the current is usually limited and only allows the extraction of small material biopsies typically ranging from 5-70um wide. Xe Plasma FIB, by contrast, has around 38x more current and can remove more material at the same time to extract significant sized chunks (100-1000um) of materials for further analysis. This increased volume has enabled time-prohibitive investigations like large grain 3D serial sectioning and EBSD and micro-machining for micro-mechanical testing. Investigation of the pore spaces with 3D modeling can determine the relative characteristics of the materials to help design or select properties for best function. Pore spaces can be described with a tortuosity number which is calculated by modules in the 3D analysis software. Xe Plasma FIB technology provides a workflow with sufficient volume to characterize porosity when both large-volume 3D materials characterization and nanometer resolution is required to understand the system.Keywords: dual-beam, FIB-SEM, porosity, SOFC, solid oxide fuel cell
Procedia PDF Downloads 20725165 Multiscale Cohesive Zone Modeling of Composite Microstructure
Authors: Vincent Iacobellis, Kamran Behdinan
Abstract:
A finite element cohesive zone model is used to predict the temperature dependent material properties of a polyimide matrix composite with unidirectional carbon fiber arrangement. The cohesive zone parameters have been obtained from previous research involving an atomistic-to-continuum multiscale simulation of the fiber-matrix interface using the bridging cell multiscale method. The goal of the research was to both investigate the effect of temperature change on the composite behavior with respect to transverse loading as well as the validate the use of cohesive parameters obtained from atomistic-to-continuum multiscale modeling to predict fiber-matrix interfacial cracking. From the multiscale model cohesive zone parameters (i.e. maximum traction and energy of separation) were obtained by modeling the interface between the coarse-grained polyimide matrix and graphite based carbon fiber. The cohesive parameters from this simulation were used in a cohesive zone model of the composite microstructure in order to predict the properties of the macroscale composite with respect to changes in temperature ranging from 21 ˚C to 316 ˚C. Good agreement was found between the microscale RUC model and experimental results for stress-strain response, stiffness, and material strength at low and high temperatures. Examination of the deformation of the composite through localized crack initiation at the fiber-matrix interface also agreed with experimental observations of similar phenomena. Overall, the cohesive zone model was shown to be both effective at modeling the composite properties with respect to transverse loading as well as validated the use of cohesive zone parameters obtained from the multiscale simulation.Keywords: cohesive zone model, fiber-matrix interface, microscale damage, multiscale modeling
Procedia PDF Downloads 48725164 Ionic Liquids as Corrosion Inhibitors in CO2 Capture Systems
Abstract:
We present the viability of using thermally stable, practically non-volatile ionic liquids as corrosion inhibitors in aqueous monoethanolamine system. Carbon steel 1020, which widely used as construction material in CO2 capture plants, has been taken as a test material. Corrosion inhibition capacities of typical room-temperature ionic liquids constituting imidazolium cation in concentration range ≤ 3% by weight in CO2 capture applications were investigated. Electrochemical corrosion experiments using the potentiodynamic polarization technique for measuring corrosion current were carried out. The results show that ionic liquids possess ability to suppressing severe operational problems of corrosion in typical CO2 capture plants.Keywords: carbon dioxide, carbon steel, monoethanolamine, corrosion rate, ionic liquids, tafel fit
Procedia PDF Downloads 32425163 Simulation and Analysis of Inverted Pendulum Controllers
Authors: Sheren H. Salah
Abstract:
The inverted pendulum is a highly nonlinear and open-loop unstable system. An inverted pendulum (IP) is a pendulum which has its mass above its pivot point. It is often implemented with the pivot point mounted on a cart that can move horizontally and may be called a cart and pole. The characteristics of the inverted pendulum make identification and control more challenging. This paper presents the simulation study of several control strategies for an inverted pendulum system. The goal is to determine which control strategy delivers better performance with respect to pendulum’s angle. The inverted pendulum represents a challenging control problem, which continually moves toward an uncontrolled state. For controlling the inverted pendulum. The simulation study that sliding mode control (SMC) control produced better response compared to Genetic Algorithm Control (GAs) and proportional-integral-derivative(PID) control.Keywords: Inverted Pendulum (IP) Proportional-Integral-Derivative (PID), Genetic Algorithm Control (GAs), Sliding Mode Control (SMC)
Procedia PDF Downloads 55525162 Influence of Thickness on Electrical and Structural Properties of Zinc Oxide (ZnO) Thin Films Prepared by RF Sputtering Technique
Authors: M. Momoh, S. Abdullahi, A. U. Moreh
Abstract:
Zinc oxide (ZnO) thin films were prepared on corning (7059) glass substrates at a thickness of 75.5 and 130.5 nm by RF sputtering technique. The deposition was carried out at room temperature after which the samples were annealed in open air at 150°C. The electrical and structural properties of these films were studied. The electrical properties of the films were monitored by four-point probe method while the structural properties were studied by X-ray diffraction (XRD). It was found that the electrical resistance of the films decreases with increase in the thickness of the films. The XRD analysis of the films showed that the films have a peak located at 34.31°-34.35° with hkl (002). Other parameters calculated include the stress (σ) and the grain size (D).Keywords: electrical properties, film thickness, structural properties, zinc oxide
Procedia PDF Downloads 379