Search results for: ductility of a joint
562 Reliability Analysis for Cyclic Fatigue Life Prediction in Railroad Bolt Hole
Authors: Hasan Keshavarzian, Tayebeh Nesari
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Bolted rail joint is one of the most vulnerable areas in railway track. A comprehensive approach was developed for studying the reliability of fatigue crack initiation of railroad bolt hole under random axle loads and random material properties. The operation condition was also considered as stochastic variables. In order to obtain the comprehensive probability model of fatigue crack initiation life prediction in railroad bolt hole, we used FEM, response surface method (RSM), and reliability analysis. Combined energy-density based and critical plane based fatigue concept is used for the fatigue crack prediction. The dynamic loads were calculated according to the axle load, speed, and track properties. The results show that axle load is most sensitive parameter compared to Poisson’s ratio in fatigue crack initiation life. Also, the reliability index decreases slowly due to high cycle fatigue regime in this area.Keywords: rail-wheel tribology, rolling contact mechanic, finite element modeling, reliability analysis
Procedia PDF Downloads 380561 Spare Part Inventory Optimization Policy: A Study Literature
Authors: Zukhrof Romadhon, Nani Kurniati
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Availability of Spare parts is critical to support maintenance tasks and the production system. Managing spare part inventory deals with some parameters and objective functions, as well as the tradeoff between inventory costs and spare parts availability. Several mathematical models and methods have been developed to optimize the spare part policy. Many researchers who proposed optimization models need to be considered to identify other potential models. This work presents a review of several pertinent literature on spare part inventory optimization and analyzes the gaps for future research. Initial investigation on scholars and many journal database systems under specific keywords related to spare parts found about 17K papers. Filtering was conducted based on five main aspects, i.e., replenishment policy, objective function, echelon network, lead time, model solving, and additional aspects of part classification. Future topics could be identified based on the number of papers that haven’t addressed specific aspects, including joint optimization of spare part inventory and maintenance.Keywords: spare part, spare part inventory, inventory model, optimization, maintenance
Procedia PDF Downloads 61560 Exploration of Critical Success Factors in Business and Management in Artificial Intelligence Era
Authors: Najah Kalifah Almazmomi
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In the time of artificial intelligence (AI), there is a need to know the determinants of success in business management, which are taking on a new dimension. This research purports to scrutinize the Critical Success Factors (CSFs) that drive and ignite the fire of success to help uncover the subtle and profound dynamics that might be operative in organizations. By means of a systematic literature review and a number of empirical methods, the paper is aimed at determining and assessing the key aspects of CSFs, putting emphasis on their role and meaning in the context of AI technology adoption. Some central features such as leadership ways, innovation models, strategic thinking methodologies, organizational culture transformations, and human resource management approaches are compared and contrasted with the AI-driven revolution. Additionally, this research will explore the interactive effects of these factors and their joint impact on the success, survival, and flexibility of a business in the current environment, which is changing due to AI development. Through the use of different qualitative and quantitative methodologies, the research concludes that the findings are significant in understanding the relative roles of individual CSFs and in studying the interactions between them in such an AI-enabled business environment.Keywords: critical success factors, business and management, artificial intelligence, leadership strategies
Procedia PDF Downloads 36559 Engineering Microstructural Evolution during Arc Wire Directed Energy Deposition of Magnesium Alloy (AZ31)
Authors: Nivatha Elangovan, Lakshman Neelakantan, Murugaiyan Amirthalingam
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Magnesium and its alloys are widely used for various lightweight engineering and biomedical applications as they render high strength to low weight ratio and excellent corrosion resistance. These alloys possess good bio-compatibility and similar mechanical properties to natural bone. However, manufacturing magnesium alloy components by conventional formative and subtractive methods is challenging due to their poor castability, oxidation potential, and machinability. Therefore, efforts are made to produce complex-design containing magnesium alloy components by additive manufacturing (AM). Arc-wire directed energy deposition (AW-DED), also known as wire arc additive manufacturing (WAAM), is more attractive to produce large volume components with increased productivity than any other AM technique. In this research work, efforts were made to optimise the deposition parameters to build thick-walled (about 10 mm) AZ31 magnesium alloy components by a gas metal arc (GMA) based AW-DED process. By using controlled dip short-circuiting metal transfer in a GMA process, depositions were carried out without defects and spatter formation. Current and voltage waveforms were suitably modified to achieve stable metal transfer. Moreover, the droplet transfer behaviour was analysed using high-speed image analysis and correlated with arc energy. Optical and scanning electron microscopy analyses were carried out to correlate the influence of deposition parameters with the microstructural evolution during deposition. The investigation reveals that by carefully controlling the current-voltage waveform and droplet transfer behaviour, it is possible to stabilise equiaxed grain microstructures in the deposited AZ31 components. The printed component exhibited an improved mechanical property as equiaxed grains improve the ductility and enhance the toughness. The equiaxed grains in the component improved the corrosion-resistant behaviour of other conventionally manufactured components.Keywords: arc wire directed energy deposition, AZ31 magnesium alloy, equiaxed grain, corrosion
Procedia PDF Downloads 122558 Protection of Human Rights in Europe: The Parliamentary Dimension
Authors: Aleksandra Chiniaeva
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The following paper describes the activity of national and international parliamentary assemblies of the European region in protection and promotion of human rights. It may be said that parliamentarians have a “double mandate” — as members of the international assembly and of their respective national parliaments. In other words, parliamentarization at both international and national level provides a situation for parliamentarians, where they link people, national governments and international organizations. The paper is aimed towards demonstrating that the activity of the main international parliamentary assemblies of the European region have a real positive impact on the human rights situation in the European region. In addition, the paper describes the assemblies that include protection of human rights in their Agenda as one of the main subjects: the EP, the PACE, the OSCE PA and the IPA CIS. Co-operation activities such as joint election observation; participation in inter-parliamentary associations, such as the IPU; conclusion agreements allow assemblies to provide observation of human right situation in the states that are not members of the particular organization and as consequence make their impact broader.Keywords: human rights, international parliamentary assembly, IPU, EP, PACE, OSCE, international election observation
Procedia PDF Downloads 364557 Effects of Damper Locations and Base Isolators on Seismic Response of a Building Frame
Authors: Azin Shakibabarough, Mojtaba Valinejadshoubi, Ashutosh Bagchi
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Structural vibration means repetitive motion that causes fatigue and reduction of the performance of a structure. An earthquake may release high amount of energy that can have adverse effect on all components of a structure. Therefore, decreasing of vibration or maintaining performance of structures such as bridges, dams, roads and buildings is important for life safety and reducing economic loss. When earthquake or any vibration happens, investigation on parts of a structure which sustain the seismic loads is mandatory to provide a safe condition for the occupants. One of the solutions for reducing the earthquake vibration in a structure is using of vibration control devices such as dampers and base isolators. The objective of this study is to investigate the optimal positions of friction dampers and base isolators for better seismic response of 2D frame. For this purpose, a two bay and six story frame with different distribution formats was modeled and some of their responses to earthquake such as inter-story drift, max joint displacement, max axial force and max bending moment were determined and compared using non-linear dynamic analysis.Keywords: fast nonlinear analysis, friction damper, base isolator, seismic vibration control, seismic response
Procedia PDF Downloads 320556 316L Passive Film Modification During Pitting Corrosion Process
Authors: Amina Sriba
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In this work, interactions between the chemical elements forming the passive film of welded austenitic stainless steel during pitting corrosion are studied. We pay special attention to the chemical elements chromium, molybdenum, iron, nickel, and silicon since they make up the passive film that covers the fusion zone's surface in the welded joint. Molybdenum and chromium are typically the two essential components that control the three crucial stages of pit formation. It was found that while the involvement of chromium is more prominent during the propagation of a pit that has already begun, the enrichment of the molybdenum element in the passive film becomes apparent from the first stage of pit initiation. Additionally, during the pitting corrosion process, there was a noticeable fluctuation in the quantities of the produced oxides and hydroxide species from zone to zone. Regarding the formed hydroxide species, we clearly see that Nickel hydroxides are added to those of Chromium to constitute the outer layer in the passive film of the fusion zone sample, compared to the base metal sample, where only Chromium hydroxide formed on its surface during the pitting corrosion process. This reaction is caused by the preferential dissolution of the austenite phase instead of ferrite in the fusion zone.Keywords: fusion zone, passive film, chemical elements, pit
Procedia PDF Downloads 50555 The Effect of Different Surface Cleaning Methods on Porosity Formation and Mechanical Property of AA6xxx Aluminum Gas Metal Arc Welds
Authors: Fatemeh Mirakhorli
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Porosity is the main issue during welding of aluminum alloys, and surface cleaning has a critical influence to reduce the porosity level by removing the oxidized surface layer before fusion welding. Developing an optimum and economical surface cleaning method has an enormous benefit for aluminum welding industries to reduce costs related to repairing and repeating welds as well as increasing the mechanical properties of the joints. In this study, several mechanical and chemical surface cleaning methods were examined for butt joint welding of 2 mm thick AA6xxx alloys using ER5556 filler metal. The effects of each method on porosity formation and tensile properties are evaluated. It has been found that, compared to the conventional mechanical cleaning method, the use of chemical cleaning leads to an important reduction in porosity level even after a significant delay between cleaning and welding. The effect of the higher porosity level in the fusion zone to reduce the tensile strength of the welds is shown.Keywords: gas metal arc welding (GMAW), aluminum alloy, surface cleaning, porosity formation, mechanical property
Procedia PDF Downloads 138554 An Analytical Study on Rotational Capacity of Beam-Column Joints in Unit Modular Frames
Authors: Kyung-Suk Choi, Hyung-Joon Kim
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Modular structural systems are constructed using a method that they are assembled with prefabricated unit modular frames on-site. This provides a benefit that can significantly reduce building construction time. Their structural design is usually carried out under the assumption that the load-carrying mechanism is similar to that of a traditional steel moment-resisting system. However, both systems are different in terms of beam-column connection details which may strongly influence the lateral structural behavior. Specially, the presence of access holes in a beam-column joint of a unit modular frame could cause undesirable failure during strong earthquakes. Therefore, this study carried out finite element analyses (FEM) of unit modular frames to investigate the cyclic behavior of beam-column joints with the structural influence of access holes. Analysis results show that the unit modular frames present stable cyclic response with large deformation capacities, and their joints are classified into semi-rigid connections.Keywords: unit modular frame, steel moment connection, nonlinear analytical model, moment-rotation relation
Procedia PDF Downloads 613553 Emotion Oriented Students' Opinioned Topic Detection for Course Reviews in Massive Open Online Course
Authors: Zhi Liu, Xian Peng, Monika Domanska, Lingyun Kang, Sannyuya Liu
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Massive Open education has become increasingly popular among worldwide learners. An increasing number of course reviews are being generated in Massive Open Online Course (MOOC) platform, which offers an interactive feedback channel for learners to express opinions and feelings in learning. These reviews typically contain subjective emotion and topic information towards the courses. However, it is time-consuming to artificially detect these opinions. In this paper, we propose an emotion-oriented topic detection model to automatically detect the students’ opinioned aspects in course reviews. The known overall emotion orientation and emotional words in each review are used to guide the joint probabilistic modeling of emotion and aspects in reviews. Through the experiment on real-life review data, it is verified that the distribution of course-emotion-aspect can be calculated to capture the most significant opinioned topics in each course unit. This proposed technique helps in conducting intelligent learning analytics for teachers to improve pedagogies and for developers to promote user experiences.Keywords: Massive Open Online Course (MOOC), course reviews, topic model, emotion recognition, topical aspects
Procedia PDF Downloads 261552 The Role of Gender Ideology in the Legality of Same-Sex Marriage: A Cross-National Analysis
Authors: Amber Salamanca-Blazek
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This paper explores the connection between gender ideology and the legality of same-sex marriage cross-nationally. The author questions what role gender ideology plays in the cultural shift concerning same-sex marriage currently underway around the world and the variations in the legal treatment of same-sex marriage at the national level. Existing literature on gender, gender ideology, the role of gender ideology in traditional and same-sex marriage, and the extent to which this connection has previously been examined is explored. Also, the author explores the relationship between gender ideology and the legality of same-sex marriage in three countries with the differing legality of same-sex marriage - The United States, where same-sex marriage was legalized in 2015, Australia, where same-sex marriage was legalized in 2017, and Iran, where the death penalty for homosexuality still exists. A comparison of gender ideology frameworks and an analysis of the political rhetoric surrounding same-sex marriage in each country are performed. It is argued that the important role of gender ideology in the legality of same-sex marriage has been greatly ignored and is in need of increased attention to assist gay rights activists in their framework. The link of gender ideology and patriarchal authority between the gay rights movement and the women’s rights movement are subsequently discussed. The author argues that because of this linkage between movements, there is a necessity for joint frameworks. Suggestions for future research are also provided.Keywords: gender ideology, same-sex marriage, same-sex marriage legality, women's rights movement
Procedia PDF Downloads 242551 Mediation Models in Triadic Relationships: Illness Narratives and Medical Education
Authors: Yoko Yamada, Chizumi Yamada
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Narrative psychology is based on the dialogical relationship between self and other. The dialogue can consist of divided, competitive, or opposite communication between self and other. We constructed models of coexistent dialogue in which self and other were positioned side by side and communicated sympathetically. We propose new mediation models for narrative relationships. The mediation models are based on triadic relationships that incorporate a medium or a mediator along with self and other. We constructed three types of mediation model. In the first type, called the “Joint Attention Model”, self and other are positioned side by side and share attention with the medium. In the second type, the “Triangle Model”, an agent mediates between self and other. In the third type, the “Caring Model”, a caregiver stands beside the communication between self and other. We apply the three models to the illness narratives of medical professionals and patients. As these groups have different views and experiences of disease or illness, triadic mediation facilitates the ability to see things from the other person’s perspective and to bridge differences in people’s experiences and feelings. These models would be useful for medical education in various situations, such as in considering the relationships between senior and junior doctors and between old and young patients.Keywords: illness narrative, mediation, psychology, model, medical education
Procedia PDF Downloads 408550 Aristotle University of Thessaloniki
Authors: Ail Akbar Emamverdian, Neriman Özada, Atabak Rahimzadeh Ilkhchi, Zahra Emamverdian
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The reverse shoulder prosthesis is an innovative procedure design to treat of (GH) joint problems with severe rotator cuff deficiency. The original reverse shoulder prosthesis was invented by France surgery in1985 and has been in clinical use in the United States in 2004. These prostheses consist of baseplate that attached to the glenoid, in order to hold a spherical component, and humeral part consist of polyethylene insert which is flat. This prosthesis is the ‘reverse’ configuration. The indications for the reverse prosthesis are: (1) treating failed hemi arthroplasty with irrecoverable rotator cuff tears, (2) relief of painful arthritis associated with cuff tear arthropathy, (3) instauration after tumor resection, (4) pseudo paralysis because of irrecoverable rotator cuff tears (5) some fractures of the shoulder which reverse shoulder prostheses is only the option for treatment. This prosthesis resulting in relief of pain and decreasing the range of motion in above indications. However, this prosthesis and its applications such as notching of the scapula, dislocation of the prosthesis parts and acromial stress fractures. In this article the reverse shoulder prostheses, indication has been reviewed. This study can make clear aspect of reverse shoulder prosthesis that can help to find some solution in future.Keywords: prostheses, complications, reverse shoulder prosthesis, indications
Procedia PDF Downloads 276549 Urinalysis by Surface-Enhanced Raman Spectroscopy on Gold Nanoparticles for Different Disease
Authors: Leonardo C. Pacheco-Londoño, Nataly J. Galan-Freyle, Lisandro Pacheco-Lugo, Antonio Acosta, Elkin Navarro, Gustavo Aroca-Martínez, Karin Rondón-Payares, Samuel P. Hernández-Rivera
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In our Life Science Research Center of the University Simon Bolivar (LSRC), one of the focuses is the diagnosis and prognosis of different diseases; we have been implementing the use of gold nanoparticles (Au-NPs) for various biomedical applications. In this case, Au-NPs were used for Surface-Enhanced Raman Spectroscopy (SERS) in different diseases' diagnostics, such as Lupus Nephritis (LN), hypertension (H), preeclampsia (PC), and others. This methodology is proposed for the diagnosis of each disease. First, good signals of the different metabolites by SERS were obtained through a mixture of urine samples and Au-NPs. Second, PLS-DA models based on SERS spectra to discriminate each disease were able to differentiate between sick and healthy patients with different diseases. Finally, the sensibility and specificity for the different models were determined in the order of 0.9. On the other hand, a second methodology was developed using machine learning models from all data of the different diseases, and, as a result, a discriminant spectral map of the diseases was generated. These studies were possible thanks to joint research between two university research centers and two health sector entities, and the patient samples were treated with ethical rigor and their consent.Keywords: SERS, Raman, PLS-DA, diseases
Procedia PDF Downloads 140548 Tutankhamen’s Shrines (Naoses): Scientific Identification of Wood Species and Technology
Authors: Medhat Abdallah, Ahmed Abdrabou
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Tutankhamen tomb was discovered on November 1922 by Howard carter, the grave was relatively intact and crammed full of the most beautiful burial items and furniture, the black shrine-shaped boxes on sleds studied here founded in treasury chamber. This study aims to identify the wood species used in making those shrines, illustrate technology of manufacture. Optical Microscope (OM), 3D software and Imaging Processes including; Visible light, Raking light and Visible-induced infrared luminescence were effective in illustrating wooden joints and techniques of manufacture. The results revealed that cedar of Lebanon Cedrus libani and sycamore fig Ficus sycomorus had been used for making the shrines’ boards and sleds while tamarisk Tamarix sp., Turkey Oak Quercus cerris L., and Sidder (nabk) Zizyphus spina christi used for making dowels. The wooden joint of mortise and tenon was used to connect the body of the shrine to the sled, while wooden pegs used to connect roof and cornice to the shrine body.Keywords: Tutankhamen, wood species, optical microscope, Cedrus libani, Ficus sycomorus
Procedia PDF Downloads 206547 Evaluation of Osteoprotegrin (OPG) and Tumor Necrosis Factor A (TNF-A) Changes in Synovial Fluid and Serum in Dogs with Osteoarthritis; An Experimental Study
Authors: Behrooz Nikahval, Mohammad Saeed Ahrari-Khafi, Sakineh Behroozpoor, Saeed Nazifi
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Osteoarthritis (OA) is a progressive and degenerative condition of the articular cartilage and other joints’ structures. It is essential to diagnose this condition as early as possible. The present research was performed to measure the Osteoprotegrin (OPG) and Tumor Necrosis Factor α (TNF-α) in synovial fluid and blood serum of dogs with surgically transected cruciate ligament as a model of OA, to evaluate if measuring of these parameters can be used as a way of early diagnosis of OA. In the present study, four mature, clinically healthy dogs were selected to investigate the effect of experimental OA, on OPG and TNF-α as a way of early detection of OA. OPG and TNF-α were measured in synovial fluid and blood serum on days 0, 14, 28, 90 and 180 after surgical transaction of cranial cruciate ligament in one stifle joint. Statistical analysis of the results showed that there was a significant increase in TNF-α in both synovial fluid and blood serum. OPG showed a decrease two weeks after OA induction. However, it fluctuated afterward. In conclusion, TNF-α could be used in both synovial fluid and blood serum as a way of early detection of OA; however, further research still needs to be conducted on OPG values in OA detection.Keywords: osteoarthritis, osteoprotegrin, tumor necrosis factor α, synovial fluid, serum, dog
Procedia PDF Downloads 316546 Internationalization Strategies and Firm Productivity: Manufacturing Firm-Level Evidence from Ethiopia
Authors: Soressa Tolcha Jarra
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Looking into firm-level internationalization strategies and their effects on firms' productivity is needed in order to understand the role of firms’ participation in trading activities on the one hand and the effects of firms’ internalization strategies on firm-level productivity on the other. Thus, this study aims to investigate firms' imports of intermediates and export strategies and their impact on firm productivity using an establishment-level panel dataset from Ethiopian manufacturing firms over the period 2011–2020. Methodologically, the joint firm’s decision to import intermediates and estimate exports is undertaken by system GMM using Wooldridge's approach. The translog-production function is used to estimate firm-level productivity by considering a general Markov process. The size of the firm is used in a mediating role. The result indicates evidence of the self-selection of more productive firms into exporting and importing intermediates, which is indicative of sizable export and import market entry costs. Furthermore, there is evidence in favor of learning by exporting (LBE) and learning by importing (LBI) hypotheses for smaller and medium Ethiopian manufacturing firms. However, for large firms, there is only evidence in support of the learning by exporting (LBE) hypothesis.Keywords: Ethiopia, export, firm productivity, intermediate imports
Procedia PDF Downloads 34545 3D Reconstruction of Human Body Based on Gender Classification
Authors: Jiahe Liu, Hongyang Yu, Feng Qian, Miao Luo
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SMPL-X was a powerful parametric human body model that included male, neutral, and female models, with significant gender differences between these three models. During the process of 3D human body reconstruction, the correct selection of standard templates was crucial for obtaining accurate results. To address this issue, we developed an efficient gender classification algorithm to automatically select the appropriate template for 3D human body reconstruction. The key to this gender classification algorithm was the precise analysis of human body features. By using the SMPL-X model, the algorithm could detect and identify gender features of the human body, thereby determining which standard template should be used. The accuracy of this algorithm made the 3D reconstruction process more accurate and reliable, as it could adjust model parameters based on individual gender differences. SMPL-X and the related gender classification algorithm have brought important advancements to the field of 3D human body reconstruction. By accurately selecting standard templates, they have improved the accuracy of reconstruction and have broad potential in various application fields. These technologies continue to drive the development of the 3D reconstruction field, providing us with more realistic and accurate human body models.Keywords: gender classification, joint detection, SMPL-X, 3D reconstruction
Procedia PDF Downloads 68544 Application of Electrical Resistivity Tomography to Image the Subsurface Structure of a Sinkhole, a Case Study in Southwestern Missouri
Authors: Shishay T. Kidanu
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The study area is located in Southwestern Missouri and is mainly underlain by Mississippian Age limestone which is highly susceptible to karst processes. The area is known for the presence of various karst features like caves, springs and more importantly Sinkholes. Sinkholes are one of the most common karst features and the primary hazard in karst areas. Investigating the subsurface structure and development mechanism of existing sinkholes enables to understand their long-term impact and chance of reactivation and also helps to provide effective mitigation measures. In this study ERT (Electrical Resistivity Tomography), MASW (Multichannel Analysis of Surface Waves) and borehole control data have been used to image the subsurface structure and investigate the development mechanism of a sinkhole in Southwestern Missouri. The study shows that the main process responsible for the development of the sinkhole is the downward piping of fine grained soils. Furthermore, the study reveals that the sinkhole developed along a north-south oriented vertical joint set characterized by a vertical zone of water seepage and associated fine grained soil piping into preexisting fractures.Keywords: ERT, Karst, MASW, sinkhole
Procedia PDF Downloads 212543 Intelligent Rheumatoid Arthritis Identification System Based Image Processing and Neural Classifier
Authors: Abdulkader Helwan
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Rheumatoid joint inflammation is characterized as a perpetual incendiary issue which influences the joints by hurting body tissues Therefore, there is an urgent need for an effective intelligent identification system of knee Rheumatoid arthritis especially in its early stages. This paper is to develop a new intelligent system for the identification of Rheumatoid arthritis of the knee utilizing image processing techniques and neural classifier. The system involves two principle stages. The first one is the image processing stage in which the images are processed using some techniques such as RGB to gryascale conversion, rescaling, median filtering, background extracting, images subtracting, segmentation using canny edge detection, and features extraction using pattern averaging. The extracted features are used then as inputs for the neural network which classifies the X-ray knee images as normal or abnormal (arthritic) based on a backpropagation learning algorithm which involves training of the network on 400 X-ray normal and abnormal knee images. The system was tested on 400 x-ray images and the network shows good performance during that phase, resulting in a good identification rate 97%.Keywords: rheumatoid arthritis, intelligent identification, neural classifier, segmentation, backpropoagation
Procedia PDF Downloads 531542 Analysis of Moment Rotation Curve for Steel Beam Column Joint
Authors: A. J. Shah, G. R. Vesmawala
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Connections perform a fundamental role in the steel structures as global behaviour. In order to evaluate the real influence of the physical and geometrical parameters that control their behaviour, many experimental tests and analysis have been developed but a definitive answer to the problem in question still stands. Here, various configurations of bolts were tried and the resulting moment rotation (M-θ) curves were plotted. The connection configuration is such that two bolts are located above each of the flanges and beside each of the webs. The model considers the combined effects of prying action, the formation of yield lines, and failures due to punching shear and beam section failure. For many types of connections, the stiffness at the service load level falls somewhere in between the fully restrained and simple limits and designers need to account for its behaviour. The (M-θ) curves are generally assumed to be the best characterization of connection behaviour. The moment rotation curves are generally derived from experiments on cantilever type specimens. The moments are calculated directly from the statics of the specimen, while the rotations are measured over a distance typically equal to the point of loading. Thus, this paper establishes the relationship between M-θ behaviour of different types of connections tested and presents the relative strength of various possible arrangements of bolts.Keywords: bolt, moment, rotation, stiffness, connections
Procedia PDF Downloads 391541 Study of Mechanical Properties of Aluminium Alloys on Normal Friction Stir Welding and Underwater Friction Stir Welding for Structural Applications
Authors: Lingaraju Dumpala, Laxmi Mohan Kumar Chintada, Devadas Deepu, Pravin Kumar Yadav
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Friction stir welding is the new-fangled and cutting-edge technique in welding applications; it is widely used in the fields of transportation, aerospace, defense, etc. For thriving significant welding joints and properties of friction stir welded components, it is essential to carry out this advanced process in a prescribed systematic procedure. At this moment, Underwater Friction Stir Welding (UFSW) Process is the field of interest to do research work. In the continuous assessment, the study of UFSW process is to comprehend problems occurred in the past and the structure through which the mechanical properties of the welded joints can be value-added and contributes to conclude results an acceptable and resourceful joint. A meticulous criticism is given on how to modify the experimental setup from NFSW to UFSW. It can discern the influence of tool materials, feeds, spindle angle, load, rotational speeds and mechanical properties. By expending the DEFORM-3D simulation software, the achieved outcomes are validated.Keywords: Underwater Friction Stir Welding(UFSW), Al alloys, mechanical properties, Normal Friction Stir Welding(NFSW)
Procedia PDF Downloads 287540 21st Century Provocation: Modern Slavery, the Implications for Individuals on the Autism Spectrum
Authors: Christina Surmei
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Autism Spectrum Disorder (ASD) is defined as a diverse range of developmental conditions that affect an individual’s functionality. ASD is not linear, and individuals can present with deficits in social interaction, communication, and demonstrate limited, repetitive patterns of behaviour, interests, or activities. These characteristics may be observed in a variety of ways and range from mild to severe. ASD may include autism disorder, pervasive developmental disorder not otherwise specified, Asperger’s, or other related pervasive developmental disorders. Modern slavery is defined as 'situations of exploitation that a person cannot refuse or leave because of threats, violence, coercion, and abuse of power or deception'. A review of the literature investigated the prevalence of research regarding ASD and modern slavery. Two universal search engines and five online journals were used as the apparatuses of inquiry. The results revealed two editorials, one study, and one act, totaling four publications attesting to ASD and modern slavery as a joint entity. This is representative of a vast absence of research. However, as individual entities research on autism and modern slavery is in a general high occurrence. This paper has identified a significant gap in research on ASD and modern slavery, and initiates the dialogue to unpack a significant global issue in society today.Keywords: autism spectrum, education, modern slavery, support
Procedia PDF Downloads 166539 Design and Development of an Application for the Evaluation of Personal Injury and Disability in Occupational and Forensic Medicine
Authors: Daniel Suárez, Jesús Tomas, Sandra Sendra, Sandra Viciano-Tudela, Luis Felipe Calle, Javier Urios, Jaime Lloret
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Our study is to develop a tool for the mobile phone to an assessment of body damage or determination of the degree of disability. This is a field of action of legal medicine and insurance with obvious economic implications. Those people who have suffered an accident or bodily harm demand a quantification of it. The assessment of bodily harm or disability by the expert medical professional is not exempt from complexity. Sometimes it is difficult to quantify pain; other times, the doctor faces simulators or exaggerators, and on many occasions, it is difficult to remember the extensive tables of scales whose details are complex to remember and apply. We present a tool, as a mobile application, that allows entering the sociodemographic date of the patient as well as the characteristics of the accident suffered by the person. With these preliminary data and introducing bodily damage, an approximate calculation of the compensation that the injured party should receive can be made. One of the results of this study is that it allows calculating joint mobility angles without the need to use a goniometer.Keywords: mobile tool, body damage, personal injury and disability, telemedicine
Procedia PDF Downloads 88538 Digital Economy as an Alternative for Post-Pandemic Recovery in Latin America: A Literature Review
Authors: Armijos-Orellana Ana, González-Calle María, Maldonado-Matute Juan, Guerrero-Maxi Pedro
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Nowadays, the digital economy represents a fundamental element to guarantee economic and social development, whose importance increased significantly with the arrival of the COVID-19 pandemic. However, despite the benefits it offers, it can also be detrimental to those developing countries characterized by a wide digital divide. It is for this reason that the objective of this research was to identify and describe the main characteristics, benefits, and obstacles of the digital economy for Latin American countries. Through a bibliographic review, using the analytical-synthetic method in the period 1995-2021, it was determined that the digital economy could give way to structural changes, reduce inequality, and promote processes of social inclusion, as well as promote the construction and participatory development of organizational structures and institutional capacities in Latin American countries. However, the results showed that the digital economy is still incipient in the region and at least three factors are needed to establish it: joint work between academia, the business sector and the State, greater emphasis on learning and application of digital transformation and the creation of policies that encourage the creation of digital organizations.Keywords: developing countries, digital divide, digital economy, digital literacy, digital transformation
Procedia PDF Downloads 138537 Resiliency, Peer and Parental Support as Determinants of Adolescents' Social Adjustment among Secondary Students in Ilorin, Kwara State
Authors: Titilola Adebowale
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Some factors are responsible for the social adjustment among the adolescents. The study investigated resiliency, peer and parental support as factors that could determine social adjustment among adolescents in Ilorin, Kwara state. The study adopted descriptive survey research design. A sample size of 300 SS1 & SS2 students from ten secondary schools, six public and four private schools were randomly selected within Ilorin Metropolis. Self-structured questionnaire that was validated and the reliability ensured was used to collect data from the respondents. Four hypotheses were postulated and tested at 0.05 level of significance. Data collected was analysed using Pearson Product Moment Correlation (PPMC) and Regression Analysis. The findings revealed that there was a positive relationship between resiliency and social adjustment: r (298) = .402, p<0.01, r2 = .162; that there was a positive relationship between peer support and social adjustment: r (298) = .570, p<0.01, r2 = .325; that there was a positive relationship between parental support and social adjustment: r (298) = .451, p<0.01, r2 = .203; also reveals significant joint contribution of the independent variables (resilience, peer support, parental support) to the prediction of social adjustment: F (3,296) = 55.587, P<0.01. Various recommendations were given which includes the roles of government, agencies, individuals, parents, teachers, religious and marriage institutions.Keywords: resiliency, peer support, parental support, adolescents, social adjustment
Procedia PDF Downloads 175536 Using Electrical Impedance Tomography to Control a Robot
Authors: Shayan Rezvanigilkolaei, Shayesteh Vefaghnematollahi
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Electrical impedance tomography is a non-invasive medical imaging technique suitable for medical applications. This paper describes an electrical impedance tomography device with the ability to navigate a robotic arm to manipulate a target object. The design of the device includes various hardware and software sections to perform medical imaging and control the robotic arm. In its hardware section an image is formed by 16 electrodes which are located around a container. This image is used to navigate a 3DOF robotic arm to reach the exact location of the target object. The data set to form the impedance imaging is obtained by having repeated current injections and voltage measurements between all electrode pairs. After performing the necessary calculations to obtain the impedance, information is transmitted to the computer. This data is fed and then executed in MATLAB which is interfaced with EIDORS (Electrical Impedance Tomography Reconstruction Software) to reconstruct the image based on the acquired data. In the next step, the coordinates of the center of the target object are calculated by image processing toolbox of MATLAB (IPT). Finally, these coordinates are used to calculate the angles of each joint of the robotic arm. The robotic arm moves to the desired tissue with the user command.Keywords: electrical impedance tomography, EIT, surgeon robot, image processing of electrical impedance tomography
Procedia PDF Downloads 270535 Levels of Selected Heavy Metals in Varieties of Vegetable oils Consumed in Kingdom of Saudi Arabia and Health Risk Assessment of Local Population
Authors: Muhammad Waqar Ashraf
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Selected heavy metals, namely Cu, Zn, Fe, Mn, Cd, Pb, and As, in seven popular varieties of edible vegetable oils collected from Saudi Arabia, were determined by graphite furnace atomic absorption spectrometry (GF-AAS) using microwave digestion. The accuracy of procedure was confirmed by certified reference materials (NIST 1577b). The concentrations for copper, zinc, iron, manganese, lead and arsenic were observed in the range of 0.035 - 0.286, 0.955 - 3.10, 17.3 - 57.8, 0.178 - 0.586, 0.011 - 0.017 and 0.011 - 0.018 µg/g, respectively. Cadmium was found to be in the range of 2.36 - 6.34 ng/g. The results are compared internationally and with standards laid down by world health agencies. A risk assessment study has been carried out to assess exposure to these metals via consumption of vegetable oils. A comparison has been made with safety intake levels for these heavy metals recommended by Institute of Medicine of the National Academies (IOM), US Environmental Protection Agency (US EPA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA). The results indicated that the dietary intakes of the selected heavy metals from daily consumption of 25 g of edible vegetable oils for a 70 kg individual should pose no significant health risk to local population.Keywords: vegetable oils, heavy metals, contamination, health risk assessment
Procedia PDF Downloads 449534 Thermo-Mechanical Analysis of Dissimilar Al/Cu Foil Single Lap Joints Made by Composite Metal Foil Manufacturing
Authors: Javaid Butt, Habtom Mebrahtu, Hassan Shirvani
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The paper presents a new additive manufacturing process for the production of metal and composite parts. It is termed as composite metal foil manufacturing and is a combination of laminated object manufacturing and brazing techniques. The process has been described in detail and is being used to produce dissimilar aluminum to copper foil single lap joints. A three dimensional finite element model has been developed to study the thermo-mechanical characteristics of the dissimilar Al/Cu single lap joint. The effects of thermal stress and strain have been analyzed by carrying out transient thermal analysis on the heated plates used to join the two 0.1mm thin metal foils. Tensile test has been carried out on the foils before joining and after the single Al/Cu lap joints are made, they are subjected to tensile lap-shear test to analyze the effect of heat on the foils. The analyses are designed to assess the mechanical integrity of the foils after the brazing process and understand whether or not the heat treatment has an effect on the fracture modes of the produced specimens.Keywords: brazing, laminated object manufacturing, tensile lap-shear test, thermo-mechanical analysis
Procedia PDF Downloads 339533 Preliminary Study on Analysis of Pinching Motion Actuated by Electro-Active Polymers
Authors: Doo W. Lee, Soo J. Lee, Bye R. Yoon, Jae Y. Jho, Kyehan Rhee
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Hand exoskeletons have been developed in order to assist daily activities for disabled and elder people. A figure exoskeleton was developed using ionic polymer metal composite (IPMC) actuators, and the performance of it was evaluated in this study. In order to study dynamic performance of a finger dummy performing pinching motion, force generating characteristics of an IPMC actuator and pinching motion of a thumb and index finger dummy actuated by IMPC actuators were analyzed. The blocking force of 1.54 N was achieved under 4 V of DC. A thumb and index finger dummy, which has one degree of freedom at the proximal joint of each figure, was manufactured by a three dimensional rapid prototyping. Each figure was actuated by an IPMC actuator, and the maximum fingertip force was 1.18 N. Pinching motion of a dummy was analyzed by two video cameras in vertical top and horizontal left end view planes. A figure dummy powered by IPMC actuators could perform flexion and extension motion of an index figure and a thumb.Keywords: finger exoskeleton, ionic polymer metal composite, flexion and extension, motion analysis
Procedia PDF Downloads 235