Search results for: manufacturing output
1351 Inherited Eye Diseases in Africa: A Scoping Review and Strategy for an African Longitudinal Eye Study
Authors: Bawa Yusuf Muhammad, Musa Abubakar Kana, Aminatu Abdulrahman, Kerry Goetz
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Background: Inherited eye diseases are disorders that affect globally, 1 in 1000 people. The six main world populations have created databases containing information on eye genotypes. Aim: The aim of the scoping review was to mine and present the available information to date on the genetics of inherited eye diseases within the African continent. Method: Literature Search Strategy was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). PubMed and Google Scholar searched for articles on inherited eye diseases from inception to 20th June 2022. Both Original and review articles that report on inherited, genetic or developmental/congenital eye diseases within the African Continent were included in the research. Results: A total of 1162 citations were obtained, but only 37 articles were reviewed based on the inclusion and exclusion criteria. The highest output of publications on inherited eye diseases comes from South Africa and Tunisia (about 43%), followed by Morocco and Egypt (27%), then Sub-Saharan Africa and North Africa (13.50%), while the remaining articles (16.5%) originated from Nigeria, Ghana, Mauritania Cameroon, Zimbabwe and combined article between Zimbabwe and Cameroon. Glaucoma and inherited retinal disorders represent the most studied diseases, followed by Albinism and congenital cataracts, respectively. Conclusion: Despite the growing research from Tunisia, Morocco, Egypt and South Africa, Sub-Saharan Africa remains almost a virgin region to explore the genetics of eye diseases.Keywords: inherited eye diseases, Africa, scoping review, longitudinal eye study
Procedia PDF Downloads 481350 Intelligent System of the Grinding Robot for Spiral Welded Pipe
Authors: Getachew Demeissie Ayalew, Yongtao Sun, Yang Yang
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The spiral welded pipe manufacturing industry requires strict production standards for automated grinders for welding seams. However, traditional grinding machines in this sector are insufficient due to a lack of quality control protocols and inconsistent performance. This research aims to improve the quality of spiral welded pipes by developing intelligent automated abrasive belt grinding equipment. The system has equipped with six degrees of freedom (6 DOF) KUKA KR360 industrial robots, enabling concurrent grinding operations on both internal and external welds. The grinding robot control system is designed with a PLC, and a human-machine interface (HMI) system is employed for operations. The system includes an electric speed controller, data connection card, DC driver, analog amplifier, and HMI for input data. This control system enables the grinding of spiral welded pipe. It ensures consistent production quality and cost-effectiveness by reducing the product life cycle and minimizing risks in the working environment.Keywords: Intelligent Systems, Spiral Welded Pipe, Grinding, Industrial Robot, End-Effector, PLC Controller System, 3D Laser Sensor, HMI.
Procedia PDF Downloads 2781349 Characterization of a Hypoeutectic Al Alloy Obtained by Selective Laser Melting
Authors: Jairo A. Muñoz, Alexander Komissarov, Alexander Gromov
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In this investigation, a hypoeutectic AlSi11Cu alloy was printed. This alloy was obtained in powder form with an average particle size of 40 µm. Bars 20 mm in diameter and 100 mm in length were printed with the building direction parallel to the bars' longitudinal direction. The microstructural characterization demonstrated an Al matrix surrounded by a Si network forming a coral-like pattern. The microstructure of the alloy showed a heterogeneous behavior with a mixture of columnar and equiaxed grains. Likewise, the texture indicated that the columnar grains were preferentially oriented towards the building direction, while the equiaxed followed a texture dominated by the cube component. On the other hand, the as-printed material strength showed higher values than those obtained in the same alloy using conventional processes such as casting. In addition, strength and ductility differences were found in the printed material, depending on the measurement direction. The highest values were obtained in the radial direction (565 MPa maximum strength and 4.8% elongation to failure). The lowest values corresponded to the transverse direction (508 MPa maximum strength and 3.2 elongation to failure), which corroborate the material anisotropy.Keywords: additive manufacturing, aluminium alloy, melting pools, tensile test
Procedia PDF Downloads 1511348 A Prediction Model for Dynamic Responses of Building from Earthquake Based on Evolutionary Learning
Authors: Kyu Jin Kim, Byung Kwan Oh, Hyo Seon Park
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The seismic responses-based structural health monitoring system has been performed to prevent seismic damage. Structural seismic damage of building is caused by the instantaneous stress concentration which is related with dynamic characteristic of earthquake. Meanwhile, seismic response analysis to estimate the dynamic responses of building demands significantly high computational cost. To prevent the failure of structural members from the characteristic of the earthquake and the significantly high computational cost for seismic response analysis, this paper presents an artificial neural network (ANN) based prediction model for dynamic responses of building considering specific time length. Through the measured dynamic responses, input and output node of the ANN are formed by the length of specific time, and adopted for the training. In the model, evolutionary radial basis function neural network (ERBFNN), that radial basis function network (RBFN) is integrated with evolutionary optimization algorithm to find variables in RBF, is implemented. The effectiveness of the proposed model is verified through an analytical study applying responses from dynamic analysis for multi-degree of freedom system to training data in ERBFNN.Keywords: structural health monitoring, dynamic response, artificial neural network, radial basis function network, genetic algorithm
Procedia PDF Downloads 2971347 Prevalence of Near Visual Impairment and Associated Factors among School Teachers in Gondar City, North West Ethiopia, 2022
Authors: Bersufekad Wubie
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Introduction: Near visual impairment is presenting near visual acuity of the eye worse than N6 at a 40 cm distance. Teachers' regular duties, such as reading books, writing on the blackboard, and recognizing students' faces, need good near vision. If a teacher has near-visual impairment, the work output is unsatisfactory. Objective: The study was aimed to assess the prevalence and associated factors near vision impairment among school teachers at Gondar city Northwest Ethiopia, August 2022. Methods: To select 567 teachers in Gondar city schools, an institutional-based cross-sectional study design with a multistage sampling technique were used. The study was conducted in selected schools from May 1 to May 30, 2022. Trained data collectors used well-structured Amharic and English language questionnaires and ophthalmic instruments for examination. The collected data were checked for completeness and entered into Epi data version 4.6, then exported to SPSS version 26 for further analysis. A binary and multivariate logistic regression model was fitted. And associated factors of the outcome variable. Result: The prevalence of near visual impairment was 64.6%, with a confidence interval of 60.3%–68.4%. Near visual impairment was significantly associated with age >= 35 years (AOR: 4.90 at 95% CI: 3.15, 7.65), having prolonged years of teaching experience (AOR: 3.29 at 95% CI: 1.70, 4.62), having a history of ocular surgery (AOR: 1.96 at 95% CI: 1.10, 4.62), smokers (AOR: 2.21 at 95% CI: 1.22, 4.07), history of ocular trauma (AOR : 1.80 at 95%CI:1.11,3.18 and uncorrected refractive error (AOR:2.01 at 95%CI:1.13,4.03). Conclusion and recommendations: This study showed the prevalence of near vision impairment among school teachers was high, and it is not a problem of the presbyopia age group alone; it also happens at a young age. So teachers' ocular health should be well accommodated in the school's eye health.Keywords: Gondar, near visual impairment, school, teachers
Procedia PDF Downloads 1301346 Web-Based Cognitive Writing Instruction (WeCWI): A Theoretical-and-Pedagogical e-Framework for Language Development
Authors: Boon Yih Mah
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Web-based Cognitive Writing Instruction (WeCWI)’s contribution towards language development can be divided into linguistic and non-linguistic perspectives. In linguistic perspective, WeCWI focuses on the literacy and language discoveries, while the cognitive and psychological discoveries are the hubs in non-linguistic perspective. In linguistic perspective, WeCWI draws attention to free reading and enterprises, which are supported by the language acquisition theories. Besides, the adoption of process genre approach as a hybrid guided writing approach fosters literacy development. Literacy and language developments are interconnected in the communication process; hence, WeCWI encourages meaningful discussion based on the interactionist theory that involves input, negotiation, output, and interactional feedback. Rooted in the e-learning interaction-based model, WeCWI promotes online discussion via synchronous and asynchronous communications, which allows interactions happened among the learners, instructor, and digital content. In non-linguistic perspective, WeCWI highlights on the contribution of reading, discussion, and writing towards cognitive development. Based on the inquiry models, learners’ critical thinking is fostered during information exploration process through interaction and questioning. Lastly, to lower writing anxiety, WeCWI develops the instructional tool with supportive features to facilitate the writing process. To bring a positive user experience to the learner, WeCWI aims to create the instructional tool with different interface designs based on two different types of perceptual learning style.Keywords: WeCWI, literacy discovery, language discovery, cognitive discovery, psychological discovery
Procedia PDF Downloads 5561345 Effect of Alloying Elements on Particle Incorporation of Boron Carbide Reinforced Aluminum Matrix Composites
Authors: Steven Ploetz, Andreas Lohmueller, Robert F. Singer
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The outstanding performance of aluminum matrix composites (AMCs) regarding stiffness/weight ratio makes AMCs attractive material for lightweight construction. Low-density boride compounds promise simultaneously an increase in stiffness and decrease in composite density. This is why boron carbide is chosen for composite manufacturing. The composites are fabricated with the stir casting process. To avoid gas entrapment during mixing and ensure nonporous composites, partial vacuum is adapted during particle feeding and stirring. Poor wettability of boron carbide with liquid aluminum hinders particle incorporation, but alloying elements such as magnesium and titanium could improve wettability and thus particle incorporation. Next to alloying elements, adapted stirring parameters and impeller geometries improve particle incorporation and enable homogenous particle distribution and high particle volume fractions of boron carbide. AMCs with up to 15 vol.% of boron carbide particles are produced via melt stirring, resulting in an increase in stiffness and strength.Keywords: aluminum matrix composites, boron carbide, stiffness, stir casting
Procedia PDF Downloads 3041344 Investigation and Estimation of State of Health of Battery Pack in Battery Electric Vehicles-Online Battery Characterization
Authors: Ali Mashayekh, Mahdiye Khorasani, Thomas Weyh
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The tendency to use the Battery-Electric vehicle (BEV) for the low and medium driving range or even high driving range has been growing more and more. As a result, higher safety, reliability, and durability of the battery pack as a component of electric vehicles, which has a great share of cost and weight of the final product, are the topics to be considered and investigated. Battery aging can be considered as the predominant factor regarding the reliability and durability of BEV. To better understand the aging process, offline battery characterization has been widely used, which is time-consuming and needs very expensive infrastructures. This paper presents the substitute method for the conventional battery characterization methods, which is based on battery Modular Multilevel Management (BM3). According to this Topology, the battery cells can be drained and charged concerning their capacity, which allows varying battery pack structures. Due to the integration of the power electronics, the output voltage of the battery pack is no longer fixed but can be dynamically adjusted in small steps. In other words, each cell can have three different states, namely series, parallel, and bypass in connection with the neighbor cells. With the help of MATLAB/Simulink and by using the BM3 modules, the battery string model is created. This model allows us to switch two cells with the different SoC as parallel, which results in the internal balancing of the cells. But if the parallel switching lasts just for a couple of ms, we can have a perturbation pulse which can stimulate the cells out of the relaxation phase. With the help of modeling the voltage response pulse of the battery, it would be possible to characterize the cell. The Online EIS method, which is discussed in this paper, can be a robust substitute for the conventional battery characterization methods.Keywords: battery characterization, SoH estimation, RLS, BEV
Procedia PDF Downloads 1421343 Lean and Six Sigma in the Freight Railway Supplier Base in South Africa: Factors Leading to Their Application
Authors: Hilda Kundai Chikwanda, Lawrence Thabo Mokhadi
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The study aimed to review the factors that lead the freight railway suppliers base in South Africa (SA) to apply the Lean and Six Sigma (L&SS) methodologies. A thorough review of the factors that lead organisations, in the different industries, to implement these methodologies was done. L&SS applications were found to be prominent in the automotive industry. In particular, the railway industry in SA and the region were reviewed in terms of challenges in capturing the freight logistics market and growing market share. Qualitative methods have been used to collect primary data and descriptive statistics was used to calculate, describe, and summarize collected research data. The results show that external factors have a greater influence on the implementation of L&SS. The study drew inferences between freight railway supplier base and the application of Lean and Six Sigma (L&SS) methodologies in the SA context. It identified challenges that leads the SA freight railway to lose market share to road freight users. It further observes and recommends that L&SS methodologies are the ideal strategy required to implement a turnaround in the trajectory of freight railways as a competitive freight transport solution.Keywords: production, methodology, manufacturing, lean, six sigma
Procedia PDF Downloads 381342 Increasing the Capacity of Plant Bottlenecks by Using of Improving the Ratio of Mean Time between Failures to Mean Time to Repair
Authors: Jalal Soleimannejad, Mohammad Asadizeidabadi, Mahmoud Koorki, Mojtaba Azarpira
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A significant percentage of production costs is the maintenance costs, and analysis of maintenance costs could to achieve greater productivity and competitiveness. With this is mind, the maintenance of machines and installations is considered as an essential part of organizational functions and applying effective strategies causes significant added value in manufacturing activities. Organizations are trying to achieve performance levels on a global scale with emphasis on creating competitive advantage by different methods consist of RCM (Reliability-Center-Maintenance), TPM (Total Productivity Maintenance) etc. In this study, increasing the capacity of Concentration Plant of Golgohar Iron Ore Mining & Industrial Company (GEG) was examined by using of reliability and maintainability analyses. The results of this research showed that instead of increasing the number of machines (in order to solve the bottleneck problems), the improving of reliability and maintainability would solve bottleneck problems in the best way. It should be mention that in the abovementioned study, the data set of Concentration Plant of GEG as a case study, was applied and analyzed.Keywords: bottleneck, golgohar iron ore mining & industrial company, maintainability, maintenance costs, reliability
Procedia PDF Downloads 3521341 Computational Analysis of the Scaling Effects on the Performance of an Axial Compressor
Authors: Junting Xiang, Jörg Uwe Schlüter, Fei Duan
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The miniaturization of gas turbines promises many advantages. Miniature gas turbines can be used for local power generation or the propulsion of small aircraft, such as UAV and MAV. However, experience shows that the miniaturization of conventional gas turbines, which are optimized at their current large size, leads to a substantial loss of efficiency and performance at smaller scales. This may be due to a number of factors, such as the Reynolds-number effect, the increased heat transfer, and manufacturing tolerances. In the present work, we focus on computational investigations of the Reynolds number effect and the wall heat transfer on the performance of axial compressor during its size change. The NASA stage 35 compressors are selected as the configuration in this study and Computational Fluid Dynamics (CFD) is used to carry out the miniaturization process and simulations. We perform parameter studies on the effect of Reynolds number and wall thermal conditions. Our results indicate a decrease of efficiency, if the compressor is miniaturized based on its original geometry due to the increase of viscous effects. The increased heat transfer through wall has only a small effect and will actually benefit compressor performance based on our study.Keywords: axial compressor, CFD, heat transfer, miniature gas turbines, Reynolds number
Procedia PDF Downloads 4081340 Development of the Internal Educational Quality Assurance System of Suan Sunandha Rajabhat University
Authors: Nipawan Tharasak, Sajeewan Darbavasu
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This research aims 1) to study the opinion, problems and obstacles to internal educational quality assurance system for individual and the university levels, 2) to propose an approach to the development of quality assurance system of Suan Sunandha Rajabhat University. A study of problems and obstacles to internal educational quality assurance system of the university conducted with sample group consisting of staff and quality assurance committee members of the year 2010. There were 152 respondents. 5 executives were interviewed. Tool used in the research was document analysis. The structure of the interview questions and questionnaires with 5-rate scale. Reliability was 0.981. Data analysis were percentage, mean and standard deviation with content analysis. Results can be divided into 3 main points: (1) The implementation of the internal quality assurance system of the university. It was found that in overall, input, process and output factors received high scores. Each item is considered, the preparation, planning, monitoring and evaluation. The results of evaluation to improve the reporting and improvement according to an evaluation received high scores. However, the process received an average score. (2) Problems and obstacles. It was found that the personnel responsible for the duty still lack understanding of indicators and criteria of the quality assurance. (3) Development approach: -Staff should be encouraged to develop a better understanding of the quality assurance system. -Database system for quality assurance should be developed. -The results and suggestions should be applied in the next year development planning.Keywords: development system, internal quality assurance, education, educational quality assurance
Procedia PDF Downloads 2901339 Durability Study of Binary Blended High Performance Concrete
Authors: Vatsal Patel, Niraj Shah
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This paper presents the results of a laboratory study on the properties of binary blended High Performance cementitious systems containing blends of ordinary Portland cement (OPC), Porcelain Powder or Marble Powder blend proportions of 100:00, 95:05, 90:10, 85:15, 80:20 for OPC: Porcelain Powder/Marble Powder. Studies on the Engineering Properties of the cementitious concrete, namely compressive strength, flexural strength, sorptivity, rapid chloride penetration test and accelerated corrosion test have been performed and those of OPC concrete. The results show that the inclusion of Porcelain powder or Marble Powder as binary blended cement alters to a great degree the properties of the binder as well as the resulting concrete. In addition, the results show that the Porcelain powder with 85:15 proportions and Marble powder with 90:10 proportions as binary systems to produce high-performance concrete could potentially be used in the concrete construction industry particular in lowering down the volume of OPC used and lowering emission of CO2 produces during manufacturing of cement.Keywords: accelerated corrosion, binary blended cementitious system, rapid chloride penetration, sorptivity
Procedia PDF Downloads 3831338 Experimental Study of the Electrical Conductivity and Thermal Conductivity Property of Micro-based Al-Cu-Nb-Mo Alloy
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Aluminum based alloys with a certain compositional blend and manufacturing method have been reported to have excellent electrical conductors. In the current investigation, metal powders of Aluminum (Al), Copper (Cu), Niobium (Nb), and Molybdenum (Mo) were weighed in accordance with certain ratios and spread equally by combining the powder particles. The metal particles were mixed using a tube mixer for 12 hours. Before pouring into a 30mm-diameter graphite mold, pre-pressed, and placed into an SPS furnace, the thermal conductivity of the mixed metal powders was evaluated using a portable Thermtest device. Axial pressure of 50 MPa was used at a heating rate of 50 oC/min, and a multi-stage heating procedure with a holding period of 10 min. was used to sinter at temperatures between 300 oC and 480 oC. After being cooled to room temperature, the specimens were unmolded to produce the aluminum, copper, niobium, and molybdenum alloy material. The HPS 2662 Precision Four-point Probe Meter was used to determine the electrical resistivity and the values used to calculate the electrical conductivity of the sintered alloy samples. Finally, the alloy with the highest electrical conductivity and thermal conductivity qualities was the one with the following composition: Al 93.5Cu4Nb1.5Mo1. It also had a density of 3.23 g/cm3. It could be advisable for usage in automobile radiator and electric transmission line components.Keywords: Al-Cu-Nb-Mo, electrical conductivity, alloy, sintering, thermal conductivity
Procedia PDF Downloads 851337 The Impact of Experiential Learning on the Success of Upper Division Mechanical Engineering Students
Authors: Seyedali Seyedkavoosi, Mohammad Obadat, Seantorrion Boyle
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The purpose of this study is to assess the effectiveness of a nontraditional experiential learning strategy in improving the success and interest of mechanical engineering students, using the Kinematics/Dynamics of Machine course as a case study. This upper-division technical course covers a wide range of topics, including mechanism and machine system analysis and synthesis, yet the complexities of ideas like acceleration, motion, and machine component relationships are hard to explain using standard teaching techniques. To solve this problem, a thorough design project was created that gave students hands-on experience developing, manufacturing, and testing their inventions. The main goals of the project were to improve students' grasp of machine design and kinematics, to develop problem-solving and presenting abilities, and to familiarize them with professional software. A questionnaire survey was done to evaluate the effect of this technique on students' performance and interest in mechanical engineering. The outcomes of the study shed light on the usefulness of nontraditional experiential learning approaches in engineering education.Keywords: experiential learning, nontraditional teaching, hands-on design project, engineering education
Procedia PDF Downloads 881336 Textile Based Physical Wearable Sensors for Healthcare Monitoring in Medical and Protective Garments
Authors: Sejuti Malakar
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Textile sensors have gained a lot of interest in recent years as it is instrumental in monitoring physiological and environmental changes, for a better diagnosis that can be useful in various fields like medical textiles, sports textiles, protective textiles, agro textiles, and geo-textiles. Moreover, with the development of flexible textile-based wearable sensors, the functionality of smart clothing is augmented for a more improved user experience when it comes to technical textiles. In this context, conductive textiles using new composites and nanomaterials are being developed while considering its compatibility with the textile manufacturing processes. This review aims to provide a comprehensive and detailed overview of the contemporary advancements in textile-based wearable physical sensors, used in the field of medical, security, surveillance, and protection, from a global perspective. The methodology used is through analysing various examples of integration of wearable textile-based sensors with clothing for daily use, keeping in mind the technological advances in the same. By comparing various case studies, we come across various challenges textile sensors, in terms of stability, the comfort of movement, and reliable sensing components to enable accurate measurements, in spite of progress in the engineering of the wearable. Addressing such concerns is critical for the future success of wearable sensors.Keywords: flexible textile-based wearable sensors, contemporary advancements, conductive textiles, body conformal design
Procedia PDF Downloads 1721335 Artificial Neural Network Approach for Modeling Very Short-Term Wind Speed Prediction
Authors: Joselito Medina-Marin, Maria G. Serna-Diaz, Juan C. Seck-Tuoh-Mora, Norberto Hernandez-Romero, Irving Barragán-Vite
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Wind speed forecasting is an important issue for planning wind power generation facilities. The accuracy in the wind speed prediction allows a good performance of wind turbines for electricity generation. A model based on artificial neural networks is presented in this work. A dataset with atmospheric information about air temperature, atmospheric pressure, wind direction, and wind speed in Pachuca, Hidalgo, México, was used to train the artificial neural network. The data was downloaded from the web page of the National Meteorological Service of the Mexican government. The records were gathered for three months, with time intervals of ten minutes. This dataset was used to develop an iterative algorithm to create 1,110 ANNs, with different configurations, starting from one to three hidden layers and every hidden layer with a number of neurons from 1 to 10. Each ANN was trained with the Levenberg-Marquardt backpropagation algorithm, which is used to learn the relationship between input and output values. The model with the best performance contains three hidden layers and 9, 6, and 5 neurons, respectively; and the coefficient of determination obtained was r²=0.9414, and the Root Mean Squared Error is 1.0559. In summary, the ANN approach is suitable to predict the wind speed in Pachuca City because the r² value denotes a good fitting of gathered records, and the obtained ANN model can be used in the planning of wind power generation grids.Keywords: wind power generation, artificial neural networks, wind speed, coefficient of determination
Procedia PDF Downloads 1121334 A Study on the Influence of Planet Pin Parallelism Error to Load Sharing Factor
Authors: Kyung Min Kang, Peng Mou, Dong Xiang, Yong Yang, Gang Shen
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In this paper, planet pin parallelism error, which is one of manufacturing error of planet carrier, is employed as a main variable to influence planet load sharing factor. This error is categorize two group: (i) pin parallelism error with rotation on the axis perpendicular to the tangent of base circle of gear(x axis rotation in this paper) (ii) pin parallelism error with rotation on the tangent axis of base circle of gear(y axis rotation in this paper). For this study, the planetary gear system in 1.5MW wind turbine is applied and pure torsional rigid body model of this planetary gear is built using Solidworks and MSC.ADAMS. Based on quantified parallelism error and simulation model, dynamics simulation of planetary gear is carried out to obtain dynamic mesh load results with each type of error and load sharing factor is calculated with mesh load results. Load sharing factor formula and the suggestion for planetary reliability design is proposed with the conclusion of this study.Keywords: planetary gears, planet load sharing, MSC. ADAMS, parallelism error
Procedia PDF Downloads 3951333 Finite Element Analysis of a Modular Brushless Wound Rotor Synchronous Machine
Authors: H. T. Le Luong, C. Hénaux, F. Messine, G. Bueno-Mariani, S. Mollov, N. Voyer
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This paper presents a comparative study of different modular brushless wound rotor synchronous machine (MB-WRSM). The goal of the study is to highlight the structure which offers the best fault tolerant capability and the highest output performances. The fundamental winding factor is calculated by using the method based on EMF phasors as a significant criterion to select the preferred number of phases, stator slots, and poles. With the limited number of poles for a small machine (3.67kW/7000rpm), 15 different machines for preferred phase/slot/pole combinations are analyzed using two-dimensional (2-D) finite element method and compared according to three criteria: torque density, torque ripple and efficiency. The 7phase/7slot/6pole machine is chosen with the best compromise of high torque density, small torque ripple (3.89%) and high nominal efficiency (95%). This machine is then compared with a reference design surface permanent magnet synchronous machine (SPMSM). In conclusion, this paper provides an electromagnetic analysis of a new brushless wound-rotor synchronous machine using multiphase non-overlapping fractional slot double layer winding. The simulation results are discussed and demonstrate that the MB-WRSM presents interesting performance features, with overall performance closely matching that of an equivalent SPMSM.Keywords: finite element method (FEM), machine performance, modular wound rotor synchronous machine, non-overlapping concentrated winding
Procedia PDF Downloads 2841332 Support Vector Regression for Retrieval of Soil Moisture Using Bistatic Scatterometer Data at X-Band
Authors: Dileep Kumar Gupta, Rajendra Prasad, Pradeep Kumar, Varun Narayan Mishra, Ajeet Kumar Vishwakarma, Prashant K. Srivastava
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An approach was evaluated for the retrieval of soil moisture of bare soil surface using bistatic scatterometer data in the angular range of 200 to 700 at VV- and HH- polarization. The microwave data was acquired by specially designed X-band (10 GHz) bistatic scatterometer. The linear regression analysis was done between scattering coefficients and soil moisture content to select the suitable incidence angle for retrieval of soil moisture content. The 250 incidence angle was found more suitable. The support vector regression analysis was used to approximate the function described by the input-output relationship between the scattering coefficient and corresponding measured values of the soil moisture content. The performance of support vector regression algorithm was evaluated by comparing the observed and the estimated soil moisture content by statistical performance indices %Bias, root mean squared error (RMSE) and Nash-Sutcliffe Efficiency (NSE). The values of %Bias, root mean squared error (RMSE) and Nash-Sutcliffe Efficiency (NSE) were found 2.9451, 1.0986, and 0.9214, respectively at HH-polarization. At VV- polarization, the values of %Bias, root mean squared error (RMSE) and Nash-Sutcliffe Efficiency (NSE) were found 3.6186, 0.9373, and 0.9428, respectively.Keywords: bistatic scatterometer, soil moisture, support vector regression, RMSE, %Bias, NSE
Procedia PDF Downloads 4191331 Use of DNA Barcoding and UPLC-MS to Authenticate Agathosma spp. in South African Herbal Products
Authors: E. Pretorius, A. M. Viljoen, M. van der Bank
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Introduction: The phytochemistry of Agathosma crenulata and A. betulina has been studied extensively, while their molecular analysis through DNA barcoding remains virtually unexplored. This technique can confirm the identity of plant species included in a herbal product, thereby ensuring the efficacy of the herbal product and the accuracy of its label. Materials and methods: Authentic Agathosma reference material of A. betulina (n=16) and A. crenulata (n=10) were obtained. Thirteen commercial products were purchased from various health shops around Johannesburg, South Africa, using the search term “Agathosma” or “Buchu.” The plastid regions matK and ycf1 were used to barcode the Buchu products, and BRONX analysis confirmed the taxonomic identity of the samples. UPLC-MS analyses were also performed. Results: Only (30/60) 60% of the traded samples tested from 13 suppliers contained A. betulina in their herbal products. Similar results were also obtained for the UPLC-MS analysis. Conclusion: In this study, we demonstrate the application of DNA barcoding in combination with phytochemical analysis to authenticate herbal products claiming to contain Agathosma plants as an ingredient in their products. This supports manufacturing efforts to ensure that herbal products that are safe for the consumer.Keywords: Buchu, substitution, barcoding, BRONX algorithm, matK, ycf1, UPLC-MS
Procedia PDF Downloads 1231330 Investigation of the Low-Level Jet Role in Transportation of Shamal Dust Storms in Southwest Iran
Authors: Nasim Hossein Hamzeh, Abbas Ranjbar Saadat Abadi, Maggie Chel Gee Ooi, Steven Soon-Kai Kong, Christian Opp
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Dust storm is one of the most important natural disasters in the world, where the Middle East suffers frequently due to the existence of the dust belt region. As a country in the Middle East, Iran mostly is affected by the dust storms from some internal and also external dust sources, mostly originating from deserts in Iraq, Syria, and Saudi Arabia. In this study, some severe Shamal dust storms were investigated in Southwest Iran. The measured 〖PM〗_10 reached up to 834 μg m-3 in some stations in west Iran and Iran-Iraq borders, while the measured 〖PM〗_10 reached up to 4947 μg m-3 SW stations in northern shores of the Persian Gulf. During these severe dust storms, a low-level jet was observed at 930hPa atmospheric level in north Iraq and south Iraq. the jet core and its width were about 16 ms-1 and 100 km, respectively, in the cases where it is located in the NW regions of Iraq and northeastern Syria (at 35°N and 40-41°E), So the jet was stronger at higher latitudes (34°N - 35°N) than at lower latitudes (32°N). Therefore, suitable conditions have been created for lifting of dust sources located in northwestern Iraq and northeastern Syria. The topography surrounding the Mesopotamia and north of the Persian Gulf play a major role in the development of the Low-Level Jet through the interaction of meteorological conditions and mountain forcing. Also, the output of CALIPSO satellite images show dust rising to higher than 5 km in these dust cases, that confirming the influence of Shamal wind on the dust storm occurrence.Keywords: dust storm, shamal wind, the persian gulf, southwest Iran
Procedia PDF Downloads 851329 Design and Performance Evaluation of Hybrid Corrugated-GFRP Infill Panels
Authors: Woo Young Jung, Sung Min Park, Ho Young Son, Viriyavudh Sim
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This study presents a way to reduce earthquake damage and emergency rehabilitation of critical structures such as schools, high-tech factories, and hospitals due to strong ground motions associated with climate changes. Regarding recent trend, a strong earthquake causes serious damage to critical structures and then the critical structure might be influenced by sequence aftershocks (or tsunami) due to fault plane adjustments. Therefore, in order to improve seismic performance of critical structures, retrofitted or strengthening study of the structures under aftershocks sequence after emergency rehabilitation of the structures subjected to strong earthquakes is widely carried out. Consequently, this study used composite material for emergency rehabilitation of the structure rather than concrete and steel materials because of high strength and stiffness, lightweight, rapid manufacturing, and dynamic performance. Also, this study was to develop or improve the seismic performance or seismic retrofit of critical structures subjected to strong ground motions and earthquake aftershocks, by utilizing GFRP-Corrugated Infill Panels (GCIP).Keywords: aftershock, composite material, GFRP, infill panel
Procedia PDF Downloads 3321328 Study the Effect of Tolerances for Press Tool Assembly: Computer Aided Tolerance Analysis
Authors: Subodh Kumar, Ramkisan Pawar, Gopal D. Belurkar
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This paper describes a study for simple blanking tool. In blanking or piercing operation, punch and die should be concentric for proper cutting. In this study, tolerance analysis method is used to analyze the variation in the press tool assembly. Variation results into the eccentricity in between die and punch due to cumulative tolerance of parts used in assembly. 1D variation analysis were performed by CREO parametric computer aided design (CAD) Software Powered by CETOL 6σ computer aided tolerance analysis software. Use of CAD analysis software given the opportunity to find out the cause of variation in tool assembly. Accordingly, the new specification of tolerance and process setting for die set manufacturing has determined. Tolerance allocation and tolerance analysis method were performed iteratively to conclude that position tolerance as well as size tolerance of hole in top plate for bush and size tolerance of guide pillar were more responsible for eccentricity in punch and die. This work proposes optimum tolerance for press tool assembly parts to achieve 100 % yield for specified .015mm minimum tolerance zone.Keywords: blanking, GD&T (Geometric Dimension and Tolerancing), DPMU (defects per million unit), press tool, stackup analysis, tolerance allocation, yield percentage
Procedia PDF Downloads 3511327 Long-Term Sitting Posture Identifier Connected with Cloud Service
Authors: Manikandan S. P., Sharmila N.
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Pain in the neck, intermediate and anterior, and even low back may occur in one or more locations. Numerous factors can lead to back discomfort, which can manifest into sensations in the other parts of your body. Up to 80% of people will have low back problems at a certain stage of their lives, making spine-related pain a highly prevalent ailment. Roughly twice as commonly as neck pain, low back discomfort also happens about as often as knee pain. According to current studies, using digital devices for extended periods of time and poor sitting posture are the main causes of neck and low back pain. There are numerous monitoring techniques provided to enhance the sitting posture for the aforementioned problems. A sophisticated technique to monitor the extended sitting position is suggested in this research based on this problem. The system is made up of an inertial measurement unit, a T-shirt, an Arduino board, a buzzer, and a mobile app with cloud services. Based on the anatomical position of the spinal cord, the inertial measurement unit was positioned on the inner back side of the T-shirt. The IMU (inertial measurement unit) sensor will evaluate the hip position, imbalanced shoulder, and bending angle. Based on the output provided by the IMU, the data will be analyzed by Arduino, supplied through the cloud, and shared with a mobile app for continuous monitoring. The buzzer will sound if the measured data is mismatched with the human body's natural position. The implementation and data prediction with design to identify balanced and unbalanced posture using a posture monitoring t-shirt will be further discussed in this research article.Keywords: IMU, posture, IOT, textile
Procedia PDF Downloads 801326 Building Up a Sustainable, Future-Proof, Export-Orientated Chili Value Chain in Bugesera District, Rwanda
Authors: Akingeneye Liliane
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The value chain concept in recent times is being used by businesses and organizations to develop and implement their businesses. Chili farming has been identified as a significant contributor to the economic growth of Bugesera district. However, numerous challenges have led to a decrease in production. The primary objective of this research was to assess the current Bugesera chili value chain, identify the bottlenecks in the value chain, and come up with interventions that can help increase the output of the Bugesera chili value chain, in a climate-smart way and enhance Long-term sustainability of the value chain. The research used a case study approach to fulfill its objectives, utilizing primary and secondary data sources. Data, both qualitative and quantitative, were gathered through semi-structured interviews conducted with 22 individual farmers, five exporters, and five supporters within the Bugesera district. A focus group discussion (FGD) with seven stakeholders was also conducted to validate the research findings. The study's results underscore the challenges faced by chili farmers and other actors in the chain, the perceptions of different stakeholders to contribute to chili production, and the importance of promoting strong collaboration among stakeholders in the chili value chain to establish a sustainable framework. Based on these findings, the study puts forward recommendations that aim to address the identified challenges and improve the chili farming sector in Bugesera. The business canvas model, as a proposed recommendation, once implemented, is believed to represent the most effective approach to enhancing chili productivity in Bugesera and securing the long-term sustainability of an export-oriented chili value chain in the district.Keywords: building, sustainable, chili, value chain
Procedia PDF Downloads 491325 Analysis of Performance Improvement Factors in Supply Chain Manufacturing Using Analytic Network Process and Kaizen
Authors: Juliza Hidayati, Yesie M. Sinuhaji, Sawarni Hasibuan
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A company producing drinking water through many incompatibility issues that affect supply chain performance. The study was conducted to determine the factors that affect the performance of the supply chain and improve it. To obtain the dominant factors affecting the performance of the supply chain used Analytic Network Process, while to improve performance is done by using Kaizen. Factors affecting the performance of the supply chain to be a reference to identify the cause of the non-conformance. Results weighting using ANP indicates that the dominant factor affecting the level of performance is the precision of the number of shipments (15%), the ability of the fulfillment of the booking amount (12%), and the number of rejected products when signing (12%). Incompatibility of the factors that affect the performance of the supply chain are identified, so that found the root cause of the problem is most dominant. Based on the weight of Risk Priority Number (RPN) gained the most dominant root cause of the problem, namely the poorly maintained engine, the engine worked for three shifts, machine parts that are not contained in the plant. Improvements then performed using the Kaizen method of systematic and sustainable.Keywords: analytic network process, booking amount, risk priority number, supply chain performance
Procedia PDF Downloads 2871324 Hardness Properties of 3D Printed PLA Parts by Fused Deposition Modeling Process
Authors: Anis A. Ansari, M. Kamil
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The development of 3D printing technology has allowed the manufacturing industry to create parts with a high degree of automation, increased design freedom, and improved mechanical performance. Fused deposition modelling (FDM) is a 3D printing technique in which successive layers of thermoplastic polymer are deposited and controlled to create a three-dimensional product. In this study, process parameters such as nozzle temperature and printing speed were chosen to investigate their effects on hardness properties. 3D printed specimens were fabricated by an FDM 3D printer from Polylactic acid (PLA) polymer. After analysis, it was observed that the hardness property is much influenced by print speed and nozzle temperature parameters. Maximum hardness was achieved at higher print speed which indicates that the Shore D hardness is directly proportional to the print speed. Moreover, at higher print speed, it has no significant dependence on the nozzle temperature. Hardness is also influenced by nozzle temperature, though to a lesser extent. The hardness slightly lowers when the nozzle temperature is raised from 190 to 210 oC, but due to improved bonding between each raster, a further rise in temperature increases the hardness property.Keywords: 3D printing, fused deposition modeling (FDM), polylactic acid (PLA), print speed, nozzle temperature, hardness property
Procedia PDF Downloads 851323 Performance Evaluation of a Small Microturbine Cogeneration Functional Model
Authors: Jeni A. Popescu, Sorin G. Tomescu, Valeriu A. Vilag
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The paper focuses on the potential methods of increasing the performance of a microturbine by combining additional elements available for utilization in a cogeneration plant. The activity is carried out within the framework of a project aiming to develop, manufacture and test a microturbine functional model with high potential in energetic industry utilization. The main goal of the analysis is to determine the parameters of the fluid flow passing through each section of the turbine, based on limited data available in literature for the focus output power range or provided by experimental studies, starting from a reference cycle, and considering different cycle options, including simple, intercooled and recuperated options, in order to optimize a small cogeneration plant operation. The studied configurations operate under the same initial thermodynamic conditions and are based on a series of assumptions, in terms of individual performance of the components, pressure/velocity losses, compression ratios, and efficiencies. The thermodynamic analysis evaluates the expected performance of the microturbine cycle, while providing a series of input data and limitations to be included in the development of the experimental plan. To simplify the calculations and to allow a clear estimation of the effect of heat transfer between fluids, the working fluid for all the thermodynamic evolutions is, initially, air, the combustion being modelled by simple heat addition to the system. The theoretical results, along with preliminary experimental results are presented, aiming for a correlation in terms of microturbine performance.Keywords: cogeneration, microturbine, performance, thermodynamic analysis
Procedia PDF Downloads 1621322 Dual-Actuated Vibration Isolation Technology for a Rotary System’s Position Control on a Vibrating Frame: Disturbance Rejection and Active Damping
Authors: Kamand Bagherian, Nariman Niknejad
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A vibration isolation technology for precise position control of a rotary system powered by two permanent magnet DC (PMDC) motors is proposed, where this system is mounted on an oscillatory frame. To achieve vibration isolation for this system, active damping and disturbance rejection (ADDR) technology is presented which introduces a cooperation of a main and an auxiliary PMDC, controlled by discrete-time sliding mode control (DTSMC) based schemes. The controller of the main actuator tracks a desired position and the auxiliary actuator simultaneously isolates the induced vibration, as its controller follows a torque trend. To determine this torque trend, a combination of two algorithms is introduced by the ADDR technology. The first torque-trend producing algorithm rejects the disturbance by counteracting the perturbation, estimated using a model-based observer. The second torque trend applies active variable damping to minimize the oscillation of the output shaft. In this practice, the presented technology is implemented on a rotary system with a pendulum attached, mounted on a linear actuator simulating an oscillation-transmitting structure. In addition, the obtained results illustrate the functionality of the proposed technology.Keywords: active damping, discrete-time nonlinear controller, disturbance tracking algorithm, oscillation transmitting support, position control, stability robustness, vibration isolation
Procedia PDF Downloads 96