Search results for: tool proposal
5325 Heuristic Evaluation of Children’s Authoring Tool for Game Making
Authors: Laili Farhana Md Ibharim, Maizatul Hayati Mohamad Yatim
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The main purpose of this study is to evaluate the heuristic inspection of children’s authoring tools to develop games. The researcher has selected 15 authoring tools for making games specifically for educational purposes. Nine students from Diploma of Game Design and Development course and four lecturers from the computing department involved in this evaluation. A set of usability heuristic checklist used as a guideline for the students and lecturers to observe and test the authoring tools selected. The study found that there are just a few authoring tools that fulfill most of the heuristic requirement and suitable to apply to children. In this evaluation, only six out of fifteen authoring tools have passed above than five elements in the heuristic inspection checklist. The researcher identified that in order to develop a usable authoring tool developer has to emphasis children acceptance and interaction of the authoring tool. Furthermore, the authoring tool can be a tool to enhance their mental development especially in creativity and skill.Keywords: authoring tool, children, game making, heuristic
Procedia PDF Downloads 3435324 Nonparametric Estimation of Risk-Neutral Densities via Empirical Esscher Transform
Authors: Manoel Pereira, Alvaro Veiga, Camila Epprecht, Renato Costa
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This paper introduces an empirical version of the Esscher transform for risk-neutral option pricing. Traditional parametric methods require the formulation of an explicit risk-neutral model and are operational only for a few probability distributions for the returns of the underlying. In our proposal, we make only mild assumptions on the pricing kernel and there is no need for the formulation of the risk-neutral model for the returns. First, we simulate sample paths for the returns under the physical distribution. Then, based on the empirical Esscher transform, the sample is reweighted, giving rise to a risk-neutralized sample from which derivative prices can be obtained by a weighted sum of the options pay-offs in each path. We compare our proposal with some traditional parametric pricing methods in four experiments with artificial and real data.Keywords: esscher transform, generalized autoregressive Conditional Heteroscedastic (GARCH), nonparametric option pricing
Procedia PDF Downloads 4835323 A 3Y/3Y Pole-Changing Winding of High-Power Asynchronous Motors
Authors: Gábor Kovács
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Requirement for pole-changing motors emerged at the very early times of asynchronous motor design. Different solutions have been elaborated and some of them are generally used. An alternative is the so called 3 Y/3 Y pole-changing winding. This paper deals with high power application of this solution. A complete and comprehensive study is introduced, including features and design guidelines. The method presented in this paper is especially suitable for pole numbers being close to each other. The study also reveals that the method is more advantageous then the existing solutions for high power motors with 1:3 pole ratio. Using this motor, a new and complete drive supply system has been proposed as most appropriate arrangement of high power main naval propulsion drive. Further, the method makes possible to extend the pole ratio to 1:6, 1:9, 1:12, etc. At the end, the proposal is further extended to the here so far missing 1:4, 1:5, 1:7 etc. pole ratios. A complete proposal for the theoretically infinite range has been given in this way.Keywords: induction motor, pole changing 3Y/3Y, pole phase modulation, pole changing 1:3, 1:6
Procedia PDF Downloads 1645322 Reusing of HSS Hacksaw Blades as Rough Machining Tool
Authors: Raja V., Chokkalingam B.
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For rough cutting, in many industries and educational institutions using carbon steels or HSS single point cutting tools in center lathe machine. In power hacksaw blades, only the cutter teeth region used to parting off the given material. The portions other than the teeth can be used as a single point cutting tool for rough turning and facing on soft materials. The hardness and Tensile strength of this used Power hacksaw blade is almost same as conventional cutting tools. In this paper, the effect of power hacksaw blades over conventional tool has been compared. Thickness of the blade (1.6 mm) is very small compared to its length and width. Hence, a special tool holding device is designed to hold the tool.Keywords: hardness, high speed steels, power hacksaw blade, tensile strength
Procedia PDF Downloads 4515321 Proposed Intervention to the Attention of Harassment at a Public University
Authors: R. Echeverría Echeverría, C. Carrillo Trujillo, N. Evia Alamilla
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Today, bullying is an expression of violence. It is a present problem in different contexts. Bullying and harassment have become subject matter of professional psychology , anthropology and other social sciences and related areas. However, most research on bullying have focused on peer violence and basic education. There is little attention to harassment in higher education. It also has little generation of research and interventions in universities, undergraduate and postgraduate level. The aim of this paper is to present a proposal for intervention to the attention of college students who have had an experience of harassment and / or bullying in a Public University of Merida, Yucatan, Mexico. The methodology was qualitative phenomenological. Semiestructura interview techniques and focus groups were used. 6 students participated who have lived harassment or bullying. Also they are participating teachers and university leaders who play an important role in the presence of such cases. The purpose is to analyze the presence of policies for the prevention, treatment and punishment of those problems. The qualitative data analysis will be based on the general proposal of Rodriguez Gomez Gil Flores and García Jiménez (1999). The results show the need to create a body entrusted to provide timely attention to cases of bullying or harassment that are reported. It is important to take legal and psychological support of the University authorities. It is proposed to create a mechanism to ensure timely care and not victimized who has had the experience; in addition to the punishment of those who exercised to ensure that violence. In discussing the successes and failures of the proposal are highlighted. And the processes that have been facilitated or hampered progress for the project.Keywords: bullying, harassment, intervention, public university
Procedia PDF Downloads 2985320 Preliminary Proposal to Use Adaptive Computer Games in the Virtual Rehabilitation Therapy
Authors: Mamoun S. Ideis, Zein Salah
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Virtual Rehabilitation (VR) refers to using Virtual Reality’s hardware and simulations as means of exercising tools to rehabilitate patients in need. These patients will undergo their treatment exercises while playing different computer games, which helps achieve greater motivation for patients undergoing their therapeutic exercises. Virtual Rehabilitation systems adopt computer games as part of the treatment therapy. In this paper, we present a preliminary proposal to using adaptive computer games in Virtual Rehabilitation therapy. We also present some tips in designing those adaptive computer games by using different machine learning algorithms in order to create a personalized experience for each patient, which in turn, increases the potential benefits of the treatment that each patient receives. Furthermore, we propose a method of comparing the results of treatment using the adaptive computer games with the results of using static and classical computer games.Keywords: virtual rehabilitation, physiotherapy, adaptive computer games, post-stroke, game design
Procedia PDF Downloads 2885319 Acoustic Emission for Tool-Chip Interface Monitoring during Orthogonal Cutting
Authors: D. O. Ramadan, R. S. Dwyer-Joyce
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The measurement of the interface conditions in a cutting tool contact is essential information for performance monitoring and control. This interface provides the path for the heat flux to the cutting tool. This elevate in the cutting tool temperature leads to motivate the mechanism of tool wear, thus affect the life of the cutting tool and the productivity. This zone is representative by the tool-chip interface. Therefore, understanding and monitoring this interface is considered an important issue in machining. In this paper, an acoustic emission (AE) technique was used to find the correlation between AE parameters and the tool-chip interface. For this reason, a response surface design (RSD) has been used to analyse and optimize the machining parameters. The experiment design was based on the face centered, central composite design (CCD) in the Minitab environment. According to this design, a series of orthogonal cutting experiments for different cutting conditions were conducted on a Triumph 2500 lathe machine to study the sensitivity of the acoustic emission (AE) signal to change in tool-chip contact length. The cutting parameters investigated were the cutting speed, depth of cut, and feed and the experiments were performed for 6082-T6 aluminium tube. All the orthogonal cutting experiments were conducted unlubricated. The tool-chip contact area was investigated using a scanning electron microscope (SEM). The results obtained in this paper indicate that there is a strong dependence of the root mean square (RMS) on the cutting speed, where the RMS increases with increasing the cutting speed. A dependence on the tool-chip contact length has been also observed. However there was no effect observed of changing the cutting depth and feed on the RMS. These dependencies have been clarified in terms of the strain and temperature in the primary and secondary shear zones, also the tool-chip sticking and sliding phenomenon and the effect of these mechanical variables on dislocation activity at high strain rates. In conclusion, the acoustic emission technique has the potential to monitor in situ the tool-chip interface in turning and consequently could indicate the approaching end of life of a cutting tool.Keywords: Acoustic emission, tool-chip interface, orthogonal cutting, monitoring
Procedia PDF Downloads 4805318 Effect of Composite Material on Damping Capacity Improvement of Cutting Tool in Machining Operation Using Taguchi Approach
Authors: Siamak Ghorbani, Nikolay Ivanovich Polushin
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Chatter vibrations, occurring during cutting process, cause vibration between the cutting tool and workpiece, which deteriorates surface roughness and reduces tool life. The purpose of this study is to investigate the influence of cutting parameters and tool construction on surface roughness and vibration in turning of aluminum alloy AA2024. A new design of cutting tool is proposed, which is filled up with epoxy granite in order to improve damping capacity of the tool. Experiments were performed at the lathe using carbide cutting insert coated with TiC and two different cutting tools made of AISI 5140 steel. Taguchi L9 orthogonal array was applied to design of experiment and to optimize cutting conditions. By the help of signal-to-noise ratio and analysis of variance the optimal cutting condition and the effect of the cutting parameters on surface roughness and vibration were determined. Effectiveness of Taguchi method was verified by confirmation test. It was revealed that new cutting tool with epoxy granite has reduced vibration and surface roughness due to high damping properties of epoxy granite in toolholder.Keywords: ANOVA, damping capacity, surface roughness, Taguchi method, vibration
Procedia PDF Downloads 3065317 Conviviality as a Principle in Natural and Social Realms
Authors: Xiao Wen Xu
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There exists a challenge of accommodating/integrating people at risk and those from various backgrounds in urban areas. The success of interdependence as a tool for survival largely rests on the mutually beneficial relationships amongst individuals within a given society. One approach to meeting this challenge has been written by Ivan Illich in his book, Tools for Conviviality, where he defines 'conviviality' as interactions that help individuals. With the goal of helping the community and applying conviviality as a principle to actors in both natural and social realms of Moss Park in Toronto, the proposal involves redesigning the park and buildings as a series of different health care, extended learning, employment support, armoury, and recreation facilities that integrate the exterior landscape as treatment, teaching, military, and recreation areas; in other words, the proposal links services with access to park space. While buildings are traditionally known to physically provide shelter, parks embody shelter and act as service, as people often find comfort and relief from being in nature, and Moss Park, in particular, is home to many people at risk. This landscape is not only an important space for the homeless community but also the rest of the neighborhood. The thesis proposes that the federal government rebuilds the current armoury, as it is an obsolete building while acknowledging the extensive future developments proposed by developers and its impact on public space. The neighbourhood is an underserved area, and the new design develops not just a new armoury, but also a complex of interrelated services, which are completely integrated into the park. The armoury is redesigned as an integral component of the community that not only serves as training facilities for reservists but also serves as an emergency shelter in sub-zero temperatures for the homeless community. This paper proposes a new design for Moss Park through examining how 'park buildings', interconnected buildings and parks, can foster empowering relationships that create a supportive public realm.Keywords: conviviality, natural, social, Ivan Illich
Procedia PDF Downloads 3955316 The Proposal of Modification of California Pipe Method for Inclined Pipe
Authors: Wojciech Dąbrowski, Joanna Bąk, Laurent Solliec
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Nowadays technical and technological progress and constant development of methods and devices applied to sanitary engineering is indispensable. Issues related to sanitary engineering involve flow measurements for water and wastewater. The precise measurement is very important and pivotal for further actions, like monitoring. There are many methods and techniques of flow measurement in the area of sanitary engineering. Weirs and flumes are well–known methods and common used. But also there are alternative methods. Some of them are very simple methods, others are solutions using high technique. The old–time method combined with new technique could be more useful than earlier. Paper describes substitute method of flow gauging (California pipe method) and proposal of modification of this method used for inclined pipe. Examination of possibility of improving and developing old–time methods is direction of the investigation.Keywords: California pipe, sewerage, flow rate measurement, water, wastewater, improve, modification, hydraulic monitoring, stream
Procedia PDF Downloads 4305315 Computational Tool for Surface Electromyography Analysis; an Easy Way for Non-Engineers
Authors: Fabiano Araujo Soares, Sauro Emerick Salomoni, Joao Paulo Lima da Silva, Igor Luiz Moura, Adson Ferreira da Rocha
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This paper presents a tool developed in the Matlab platform. It was developed to simplify the analysis of surface electromyography signals (S-EMG) in a way accessible to users that are not familiarized with signal processing procedures. The tool receives data by commands in window fields and generates results as graphics and excel tables. The underlying math of each S-EMG estimator is presented. Setup window and result graphics are presented. The tool was presented to four non-engineer users and all of them managed to appropriately use it after a 5 minutes instruction period.Keywords: S-EMG estimators, electromyography, surface electromyography, ARV, RMS, MDF, MNF, CV
Procedia PDF Downloads 5465314 Active Deformable Micro-Cutters with Nano-Abrasives
Authors: M. Pappa, C. Efstathiou, G. Livanos, P. Xidas, D. Vakondios, E. Maravelakis, M. Zervakis, A. Antoniadis
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The choice of cutting tools in manufacturing processes is an essential parameter on which the required manufacturing time, the consumed energy and the cost effort all depend. If the number of tool changing times could be minimized or even eliminated by using a single convex tool providing multiple profiles, then a significant benefit of time and energy saving, as well as tool cost, would be achieved. A typical machine contains a variety of tools in order to deal with different curvatures and material removal rates. In order to minimize the required cutting tool changes, Actively Deformable micro-Cutters (ADmC) will be developed. The design of the Actively Deformable micro-Cutters will be based on the same cutting technique and mounting method as that in typical cutters.Keywords: deformable cutters, cutting tool, milling, turning, manufacturing
Procedia PDF Downloads 4485313 The Effect of Austenitization Conditioning on the Mechanical Properties of Cr-Mo-V Hot Work Tool Steel with Different Nitrogen Addition
Authors: Iting Chiang, Cheng-Yu Wei, Chin-Teng Kuo, Po-Sheng Hsu, Yo-Lun Yang, Yung-Chang Kang, Chien-Chon Chen, Chih-Yuan Chen
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In recent years, it is reported that microalloying of nitrogen atoms within traditional Cr-Mo-V hot work tool steels can achieve better high temperature mechanical properties, which thus leads to such metallurgical approach widely utilized in the several commercial advanced hot work tool steels. Although the performance of hot work tool steel can be improved better by alloy composition design strategy, the influence of processing parameters on the mechanical property, especially on the service life of hot work tool steel, is still not fully understood yet. A longer service life of hot work tool steel can decrease the manufacturing cost effectively and thus become a research hot spot. According to several previous studies, it is generally acknowledged the service life of hot work tool steels can be increased effectively as the steels possessing higher hardness and toughness due to the formation and propagation of microcracks within the steel can be inhibited effectively. Therefore, in the present research, the designed experiments are primarily to explore the synergistic effect of nitrogen content and austenitization conditioning on the mechanical properties of hot work tool steels has been conducted and analyzed. No matter the nitrogen content, the results indicated the hardness of hot work tool steels increased as the austenitization treatment executed at higher temperature. On the other hand, an optimum toughness of hot work tool steel can be achieved as the austenitization treatment performed at a suitable temperature range. The possible explanation of such metallurgical phenomenon has been also proposed and analyzed in the present research.Keywords: hot work tool steel, Cr-Mo-V, toughness, hardness, TEM
Procedia PDF Downloads 555312 The Influence of Meteorological Properties on the Power of Night Radiation Cooling
Authors: Othmane Fahim, Naoual Belouaggadia. Charifa David, Mohamed Ezzine
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To make better use of cooling resources, systems have been derived on the basis of the use of night radiator systems for heat pumping. Using the TRNSYS tool we determined the influence of the climatic characteristics of the two zones in Morocco on the temperature of the outer surface of a Photovoltaic Thermal Panel “PVT” made of aluminum. The proposal to improve the performance of the panel allowed us to have little heat absorption during the day and give the same performance of a panel made of aluminum at night. The variation in the granite-based panel temperature recorded a deviation from the other materials of 0.5 °C, 2.5 °C on the first day respectively in Marrakech and Casablanca, and 0.2 °C and 3.2 °C on the second night. Power varied between 110.16 and 32.01 W/m² marked in Marrakech, to be the most suitable area to practice night cooling by night radiation.Keywords: smart buildings, energy efficiency, Morocco, radiative cooling
Procedia PDF Downloads 1465311 Improving Performance and Progression of Novice Programmers: Factors Considerations
Authors: Hala Shaari, Nuredin Ahmed
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Teaching computer programming is recognized to be difficult and a real challenge. The biggest problem faced by novice programmers is their lack of understanding of basic programming concepts. A visualized learning tool was developed and used by volunteered first-year students for two semesters. The purposes of this paper are firstly, to emphasize factors which directly affect the performance of our students negatively. Secondly, to examine whether the proposed tool would improve their performance and learning progression. The results of adopting this tool were conducted using a pre-survey and post-survey questionnaire. As a result, students who used the learning tool showed better performance in their programming subject.Keywords: factors, novice, programming, visualization
Procedia PDF Downloads 3575310 Effect of Tool Geometry and Welding Parameters on Macrostructure and Weld Strength in Friction Stir Welded of High Density Polyethylene Sheets
Authors: Mustafa Kemal Bilici, Memduh Kurtulmuş, İlyas Kartal, Ahmet İrfan Yükler
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Friction stir welding is a solid-state joining process that has gained acceptable progress in recent years. This method which was first used for welding of aluminum and its alloys is now employed for welding of other materials such as polymers and composites. The aim of the present work is to investigate the mechanical properties of butt joints produced by friction stir welding (FSW) in high density polyethylene sheets of 4 mm thickness. The effects of critical welding parameters and tool design have affected on mechanical properties, weld surface and macrostructure of friction stir welded polyethylene. Experiments were performed at tool rotational speeds of 600, 900, 1200 and 1500 r/min and traverse speeds of 30, 45 and 60 mm/min, tool diameters (d) of 4, 5, 6 mm and tool shoulder diameters (D) 20, 25, 30 mm. A strength value of 80 % of the base material was achieved at the isolated optimum welding condition. According to the tool design, the welding parameters and the mechanical properties changed to a great extent. The highest tensile strength was achieved at low feed rates, high tool rotation speeds and shoulder diameters/pin diameters ratio.Keywords: friction stir welding, mechanical properties, polyethylene, high density polyethylene, tool design
Procedia PDF Downloads 3905309 Milling Process of Rigid Flex Printed Circuit Board to Which Polyimide Covers the Whole Surface
Authors: Daniela Evtimovska, Ivana Srbinovska, Padraig O’Rourke
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Kostal Macedonia has the challenge to mill a rigid-flex printed circuit board (PCB). The PCB elaborated in this paper is made of FR4 material covered with polyimide through the whole surface on the one side, including the tabs where PCBs need to be separated. After milling only 1.44 meters, the updraft routing tool isn’t effective and causes polyimide debris on all PCB cuts if it continues to mill with the same tool. Updraft routing tool is used for all another product in Kostal Macedonia, and it is changing after milling 60 meters. Changing the tool adds 80 seconds to the cycle time. One solution is using a laser-cut machine. Buying a laser-cut machine for cutting only one product doesn’t make financial sense. The focus is given to find an internal solution among the options under review to solve the issue with polyimide debris. In the paper, the design of the rigid-flex panel is described deeply. It is evaluated downdraft routing tool as a possible solution which could be used for the flex rigid panel as a specific product. It is done a comparison between updraft and down draft routing tools from a technical and financial aspect of view, taking into consideration the customer requirements for the rigid-flex PCB. The results show that using the downdraft routing tool is the best solution in this case. This tool is more expensive for 0.62 euros per piece than updraft. The downdraft routing tool needs to be changed after milling 43.44 meters in comparison with the updraft tool, which needs to be changed after milling only 1.44 meters. It is done analysis which actions should be taken in order further improvements and the possibility of maximum serving of downdraft routing tool.Keywords: Kostal Macedonia, rigid flex PCB, polyimide, debris, milling process, up/down draft routing tool
Procedia PDF Downloads 1815308 Tool Wear of Aluminum/Chromium/Tungsten Based Coated Cemented Carbide Tools in Cutting Sintered Steel
Authors: Tadahiro Wada, Hiroyuki Hanyu
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In this study, to clarify the effectiveness of an aluminum/chromium/tungsten-based-coated tool for cutting sintered steel, tool wear was experimentally investigated. The sintered steel was turned with the (Al60,Cr25,W15)N-, (Al60,Cr25,W15)(C,N)- and (Al64,Cr28,W8)(C,N)-coated cemented carbide tools according to the physical vapor deposition (PVD) method. Moreover, the tool wear of the aluminum/chromium/tungsten-based-coated item was compared with that of the (Al,Cr)N coated tool. Furthermore, to clarify the tool wear mechanism of the aluminum/chromium/tungsten-coating film for cutting sintered steel, Scanning Electron Microscope observation and Energy Dispersive x-ray Spectroscopy mapping analysis were conducted on the abraded surface. The following results were obtained: (1) The wear progress of the (Al64,Cr28,W8)(C,N)-coated tool was the slowest among that of the five coated tools. (2) Adding carbon (C) to the aluminum/chromium/tungsten-based-coating film was effective for improving the wear-resistance. (3) The main wear mechanism of the (Al60,Cr25,W15)N-, the (Al60,Cr25,W15)(C,N)- and the (Al64,Cr28,W8)(C,N)-coating films was abrasive wear.Keywords: cutting, physical vapor deposition coating method, tool wear, tool wear mechanism, (Al, Cr, W)N-coating film, (Al, Cr, W)(C, N)-coating film, sintered steel
Procedia PDF Downloads 3735307 The Neurofunctional Dissociation between Animal and Tool Concepts: A Network-Based Model
Authors: Skiker Kaoutar, Mounir Maouene
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Neuroimaging studies have shown that animal and tool concepts rely on distinct networks of brain areas. Animal concepts depend predominantly on temporal areas while tool concepts rely on fronto-temporo-parietal areas. However, the origin of this neurofunctional distinction for processing animal and tool concepts remains still unclear. Here, we address this question from a network perspective suggesting that the neural distinction between animals and tools might reflect the differences in their structural semantic networks. We build semantic networks for animal and tool concepts derived from McRae and colleagues’s behavioral study conducted on a large number of participants. These two networks are thus analyzed through a large number of graph theoretical measures for small-worldness: centrality, clustering coefficient, average shortest path length, as well as resistance to random and targeted attacks. The results indicate that both animal and tool networks have small-world properties. More importantly, the animal network is more vulnerable to targeted attacks compared to the tool network a result that correlates with brain lesions studies.Keywords: animals, tools, network, semantics, small-worls, resilience to damage
Procedia PDF Downloads 5365306 A Proposal for Professional Development of Mathematics Teachers in the Kingdom of Saudi Arabia According to the Orientation of Science, Technology, Engineering and Mathematics (STEM)
Authors: Ali Taher Othman Ali
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The aim of this research is to provide a draft proposal for the professional development of mathematics teachers in accordance with the orientation of science, technology, engineering and mathematics which is known by the abbreviation STEM, as a modern and contemporary orientation in the teaching and learning of mathematics and in order to achieve the objective of the research, the researcher used the theoretical descriptive method through the induction of the literature of education and the previous studies and experiments related to the topic. The researcher concluded by providing the proposal according to five basic axes, the first axe: professional development as a system, and its requirements include: development of educational systems, and allocate sufficient budgets to support the requirements of teaching STEM, identifying mechanisms for incentives and rewards for teachers attending professional development programs based on STEM; the second: development of in-depth knowledge content and its requirements include: basic sciences content development for STEM, linking the scientific understanding of teachers with real-world issues and problems, to provide the necessary resources to expand teachers' knowledge in this area; the third: the necessary pedagogical skills of teachers in the field of STEM, and its requirements include: identification of the required training and development needs and the mechanism of determining these needs, the types of professional development programs and the mechanism of designing it, the mechanisms and places of execution, evaluation and follow-up; the fourth: professional development strategies and mechanisms in the field of STEM, and its requirements include: using a variety of strategies to enable teachers to design and transfer effective educational experiences which reflect their scientific mastery in the fields of STEM, provide learning opportunities, and developing the skills of procedural research to generate new knowledge about the STEM; the fifth: to support professional development in the area of STEM, and its requirements include: support leadership within the school, provide a clear and appropriate opportunities for professional development for teachers within the school through professional learning communities, building partnerships between the Ministry of education and the local and international community institutions. The proposal includes other factors that should be considered when implementing professional development programs for mathematics teachers in the field of STEM.Keywords: professional development, mathematics teachers, the orientation of science, technology, engineering and mathematics (STEM)
Procedia PDF Downloads 3955305 Texturing of Tool Insert Using Femtosecond Laser
Authors: Ashfaq Khan, Aftab Khan, Mushtaq Khan, Sarem Sattar, Mohammad A Sheikh, Lin Li
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Chip removal processes are one of key processes of the manufacturing industry where chip removal is conducted by tool inserts of exceptionally hard materials. Tungsten carbide has been extensively used as tool insert for machining processes involving chip removal processes. These hard materials are generally fabricated by single step sintering process as further modification after fabrication in these materials cannot be done easily. Advances in tool surface modification have revealed that advantages such as improved tribological properties and extended tool life can be harnessed from the same tool by texturing the tool rake surface. Moreover, it has been observed that the shape and location of the texture also influences the behavior. Although texturing offers plentiful advantages the challenge lies in the generation of textures on the tool surface. Extremely hard material such as diamond is required to process tungsten carbide. Laser is unique processing tool that does not have a physical contact with the material and thus does not wear. In this research the potential of utilizing laser for texturing of tungsten carbide to develop custom features would be studied. A parametric study of texturing of Tungsten Carbide with a femtosecond laser would be conducted to investigate the process parameters and establish the feasible processing window. The effect of fluence, scan speed and number of repetition would be viewed in detail. Moreover, the mechanism for the generation of features would also be reviewed.Keywords: laser, texturing, femtosecond, tungsten carbide
Procedia PDF Downloads 6485304 Modeling of the Dynamic Characteristics of a Spindle with Experimental Validation
Authors: Jhe-Hao Huang, Kun-Da Wu, Wei-Cheng Shih, Jui-Pin Hung
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This study presented the investigation on the dynamic characteristics of a spindle tool system by experimental and finite element modeling approaches. As well known facts, the machining stability is greatly determined by the dynamic characteristics of the spindle tool system. Therefore, understanding the factors affecting dynamic behavior of a spindle tooling system is a prerequisite in dominating the final machining performance of machine tool system. To this purpose, a physical spindle unit was employed to assess the dynamic characteristics by vibration tests. Then, a three-dimensional finite element model of a high-speed spindle system integrated with tool holder was created to simulate the dynamic behaviors. For modeling the angular contact bearings, a series of spring elements were introduced between the inner and outer rings. The spring constant can be represented by the contact stiffness of the rolling bearing based on Hertz theory. The interface characteristic between spindle nose and tool holder taper can be quantified from the comparison of the measurements and predictions. According to the results obtained from experiments and finite element predictions, the vibration behavior of the spindle is dominated by the bending deformation of the spindle shaft in different modes, which is further determined by the stiffness of the bearings in spindle housing. Also, the spindle unit with tool holder shows a different dynamic behavior from that of spindle without tool holder. This indicates the interface property between tool holder and spindle nose plays an dominance on the dynamic characteristics the spindle tool system. Overall, the dynamic behaviors the spindle with and without tool holder can be successfully investigated through the finite element model proposed in this study. The prediction accuracy is determined by the modeling of the rolling interface of ball bearings in spindles and the interface characteristics between tool holder and spindle nose. Besides, identifications of the interface characteristics of a ball bearing and spindle tool holder are important for the refinement of the spindle tooling system to achieve the optimum machining performance.Keywords: contact stiffness, dynamic characteristics, spindle, tool holder interface
Procedia PDF Downloads 2945303 Effect of Tool Size and Cavity Depth on Response Characteristics during Electric Discharge Machining on Superalloy Metal - An Experimental Investigation
Authors: Sudhanshu Kumar
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Electrical discharge machining, also known as EDM, process is one of the most applicable machining process for removal of material in hard to machine materials like superalloy metals. EDM process utilizes electrical energy into sparks to erode the metals in presence of dielectric medium. In the present investigation, superalloy, Inconel 718 has been selected as workpiece and electrolytic copper as tool electrode. Attempt has been made to understand the effect of size of tool with varying cavity depth during drilling of hole through EDM process. In order to systematic investigate, tool size in terms of tool diameter and cavity depth along with other important electrical parameters namely, peak current, pulse-on time and servo voltage have been varied at three different values and the experiments has been designed using fractional factorial (Taguchi) method. Each experiment has been repeated twice under the same condition in order to understand the variability within the experiments. The effect of variations in parameters has been evaluated in terms of material removal rate, tool wear rate and surface roughness. Results revel that change in tool diameter during machining affects the response characteristics significantly. Larger tool diameter yielded 13% more material removal rate than smaller tool diameter. Analysis of the effect of variation in cavity depth is notable. There is no significant effect of cavity depth on material removal rate, tool wear rate and surface quality. This indicates that number of experiments can be performed to analyze other parameters effect even at smaller depth of cavity which can reduce the cost and time of experiments. Further, statistical analysis has been carried out to identify the interaction effect between parameters.Keywords: EDM, Inconel 718, material removal rate, roughness, tool wear, tool size
Procedia PDF Downloads 2055302 Toward an Understanding of the Neurofunctional Dissociation between Animal and Tool Concepts: A Graph Theoretical Analysis
Authors: Skiker Kaoutar, Mounir Maouene
Abstract:
Neuroimaging studies have shown that animal and tool concepts rely on distinct networks of brain areas. Animal concepts depend predominantly on temporal areas while tool concepts rely on fronto-temporo-parietal areas. However, the origin of this neurofunctional distinction for processing animal and tool concepts remains still unclear. Here, we address this question from a network perspective suggesting that the neural distinction between animals and tools might reflect the differences in their structural semantic networks. We build semantic networks for animal and tool concepts derived from Mc Rae and colleagues’s behavioral study conducted on a large number of participants. These two networks are thus analyzed through a large number of graph theoretical measures for small-worldness: centrality, clustering coefficient, average shortest path length, as well as resistance to random and targeted attacks. The results indicate that both animal and tool networks have small-world properties. More importantly, the animal network is more vulnerable to targeted attacks compared to the tool network a result that correlates with brain lesions studies.Keywords: animals, tools, network, semantics, small-world, resilience to damage
Procedia PDF Downloads 5385301 Verification of the Effect of the Hazard-Perception Training Tool for Drivers Ported from a Tablet Device to a Smartphone
Authors: K. Shimazaki, M. Mishina, A. Fujii
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In a previous study, we developed a hazard-perception training tool for drivers using a tablet device and verified its effectiveness. Accident movies recorded by drive recorders were separated into scenes before and after the collision. The scene before the collision is presented to the driver. The driver then touches the screen to point out where he/she feels danger. After the screen is touched, the tool presents the collision scene and tells the driver if what he/she pointed out is correct. Various effects were observed such as this tool increased the discovery rate of collision targets and reduced the reaction time. In this study, we optimized this tool for the smartphone and verified its effectiveness. Verifying in the same way as in the previous study on tablet devices clarified that the same effect can be obtained on the smartphone screen.Keywords: hazard perception, smartphone, tablet devices, driver education
Procedia PDF Downloads 2145300 A Flute Tracking System for Monitoring the Wear of Cutting Tools in Milling Operations
Authors: Hatim Laalej, Salvador Sumohano-Verdeja, Thomas McLeay
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Monitoring of tool wear in milling operations is essential for achieving the desired dimensional accuracy and surface finish of a machined workpiece. Although there are numerous statistical models and artificial intelligence techniques available for monitoring the wear of cutting tools, these techniques cannot pin point which cutting edge of the tool, or which insert in the case of indexable tooling, is worn or broken. Currently, the task of monitoring the wear on the tool cutting edges is carried out by the operator who performs a manual inspection, causing undesirable stoppages of machine tools and consequently resulting in costs incurred from lost productivity. The present study is concerned with the development of a flute tracking system to segment signals related to each physical flute of a cutter with three flutes used in an end milling operation. The purpose of the system is to monitor the cutting condition for individual flutes separately in order to determine their progressive wear rates and to predict imminent tool failure. The results of this study clearly show that signals associated with each flute can be effectively segmented using the proposed flute tracking system. Furthermore, the results illustrate that by segmenting the sensor signal by flutes it is possible to investigate the wear in each physical cutting edge of the cutting tool. These findings are significant in that they facilitate the online condition monitoring of a cutting tool for each specific flute without the need for operators/engineers to perform manual inspections of the tool.Keywords: machining, milling operation, tool condition monitoring, tool wear prediction
Procedia PDF Downloads 2975299 Using the M-Learning to Support Learning of the Concept of the Derivative
Authors: Elena F. Ruiz, Marina Vicario, Chadwick Carreto, Rubén Peredo
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One of the main obstacles in Mexico’s engineering programs is math comprehension, especially in the Derivative concept. Due to this, we present a study case that relates Mobile Computing and Classroom Learning in the “Escuela Superior de Cómputo”, based on the Educational model of the Instituto Politécnico Nacional (competence based work and problem solutions) in which we propose apps and activities to teach the concept of the Derivative. M- Learning is emphasized as one of its lines, as the objective is the use of mobile devices running an app that uses its components such as sensors, screen, camera and processing power in classroom work. In this paper, we employed Augmented Reality (ARRoC), based on the good results this technology has had in the field of learning. This proposal was developed using a qualitative research methodology supported by quantitative research. The methodological instruments used on this proposal are: observation, questionnaires, interviews and evaluations. We obtained positive results with a 40% increase using M-Learning, from the 20% increase using traditional means.Keywords: augmented reality, classroom learning, educational research, mobile computing
Procedia PDF Downloads 3575298 Experimental Evaluation of UDP in Wireless LAN
Authors: Omar Imhemed Alramli
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As Transmission Control Protocol (TCP), User Datagram Protocol (UDP) is transfer protocol in the transportation layer in Open Systems Interconnection model (OSI model) or in TCP/IP model of networks. The UDP aspects evaluation were not recognized by using the pcattcp tool on the windows operating system platform like TCP. The study has been carried out to find a tool which supports UDP aspects evolution. After the information collection about different tools, iperf tool was chosen and implemented on Cygwin tool which is installed on both Windows XP platform and also on Windows XP on virtual box machine on one computer only. Iperf is used to make experimental evaluation of UDP and to see what will happen during the sending the packets between the Host and Guest in wired and wireless networks. Many test scenarios have been done and the major UDP aspects such as jitter, packet losses, and throughput are evaluated.Keywords: TCP, UDP, IPERF, wireless LAN
Procedia PDF Downloads 3485297 The Bioequivalent: A Medical Drug Search Tool Based on a Collaborative Database
Authors: Rosa L. Figueroa, Joselyn A. Hernández
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During the last couple of years, the Ministry of Health have been developing new health policies in order to regulate and improve in benefit of the patient the pharmaceutical system in our country. However, there are still some deficiencies in how medicines have been accessed, distributed, and sold. Therefore, it is necessary to empower the patient by offering new instances to improve access to drug information. This work introduces ‘the bioequivalent’ a medical drug search tool created to increase both diffusion and getting information about the therapeutic equivalence of medicines for the patient. The development of the search tool started with a study on the availability of sources of drug information accessible to the patient where advantages and disadvantages were analyzed. The information obtained was used to feed the functional design of the new tool. The design of the new tool shows an external interface that includes a header, body, sidebar and footer. The header has a menu containing ‘Home,’ ‘Who we are,’ and ‘Mission and vision.’ The Body contains the medical drug search tool, and the Sidebar is for the user logging in. It could be anonym, registered user, as well as, administrator. Anonym user could only use the tool. Registered users could add some information on existing medicines in the database; however, adding information will be restricted and limited to specific items and subject to administrator approval because the information added must be endorsed by the Chilean Public Health Institute. On the other hand, the administrator will have all the privileges, including creating or deleting drugs or information about them. The Bioequivalent was tested on different mobile devices, and no fails have been found. Moreover, a small survey was answered by ten people who tested the tool, and all of them agree that the tool was useful to get information about bioequivalent drugs, and they would recommend the tool to others. Nevertheless, an 80% of people who tested the tool says it was easy to use, and a 70% indicates that additional help is not required. These results are evidence that ‘the Bioequivalent’ may contribute to the knowledge about the therapeutic bioequivalence and bioequivalent drugs existing in Chile. As future work, the tool will be developed to make it available to the public for a first testing stage in a more massive scenario.Keywords: collaborative database, bioequivalent drugs, search tool, web platform
Procedia PDF Downloads 2265296 Numerical Analysis of Rapid Drawdown in Dams Based on Brazilian Standards
Authors: Renato Santos Paulinelli Raposo, Vinicius Resende Domingues, Manoel Porfirio Cordao Neto
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Rapid drawdown is one of the cases referred to ground stability study in dam projects. Due to the complexity generated by the combination of loads and the difficulty in determining the parameters, analyses of rapid drawdown are usually performed considering the immediate reduction of water level upstream. The proposal of a simulation, considering the gradual reduction in water level upstream, requires knowledge of parameters about consolidation and those related to unsaturated soil. In this context, the purpose of this study is to understand the methodology of collection and analysis of parameters to simulate a rapid drawdown in dams. Using a numerical tool, the study is complemented with a hypothetical case study that can assist the practical use of data compiled. The referenced dam presents homogeneous section composed of clay soil, a height of 70 meters, a width of 12 meters, and upstream slope with inclination 1V:3H.Keywords: dam, GeoStudio, rapid drawdown, stability analysis
Procedia PDF Downloads 251