International Journal of Mathematical Engineering and Management Sciences最新文献

{"title":"Design and Development of Shape Memory Alloy Actuator for Preventing and Protecting Electrical Wires","authors":"Omar Er-Remyly, Mouna Ben Zohra, Amine Riad, A. Alhamany","doi":"10.33889/ijmems.2023.8.3.024","DOIUrl":"https://doi.org/10.33889/ijmems.2023.8.3.024","url":null,"abstract":"Fatigue failure of wires is a frequent issue that evolves over time as a result of utilizing the profile under variable stress and temperature. In this article, an innovative study makes it possible to propose a protective tool for metal profiles against fatigue using shape memory alloys (SMA). Smart actuators like SMA are able to push back sudden stresses above the elastic limit, therefore, are characterized by high resistance to fatigue and even against corrosion due to their strong thermomechanical coupling. Besides, the study provides the results necessary to add a layer based on the shape memory tube to protect the important connectors for industrial systems and automotive industries. The conductivity of electrical current in various electronic devices depends on the copper material, which is good at conducting electricity and heat but weak against mechanical forces and hence easily susceptible to fatigue. Thereby, the elastic regime of copper is different from that of SMA, and in order to adapt the properties of two materials, a mathematical study can describe the behaviour of two combined systems is important for the analysis of the cyclic effect and for adapting the proposed actuator in wiring technology. Therefore, the study shows the great potential of the proposed SMA tube with its superelastic behaviour to increase the predicted lifespan of metallic wires against corrosion and fatigue. The lifetime of the conduction system with the protective SMA is increased remarkably and can reach up to 105cycles under the action of the stress of an amplitude of 550 MPa, the finite element simulation shows that the system of SMA combined with a 4 mm wire undergoing significant stress up to 490 MPa that can reach a deformation of 7% and return to the initial state without residual deformation. The simulation's results look at the evolution of stress, strain, fatigue lifetimes, and anticipated damage, and they match the experimental results of SMA tube properties rather well. Consequently, the verification of the proposed model confirms the improvement in the lifespan of studied wires compared to wires without SMA encapsulation.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46502230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Topological Methods in the Development of Vehicle Components","authors":"Kristóf Szabó","doi":"10.21791/ijems.2023.1.9.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.9.","url":null,"abstract":"Many areas of the industry are characterized by continuous changes, which define new directions of development in product design. The development of computers and software, the spread of modern production tools and the development of material technology make it possible to expand traditional production technologies with modern processes. Integrated CAD systems have occupied their place in the product design and development process for decades, reforming classical design methods. Popular optimization procedures in integrated CAD systems, such as shape optimization, topological optimization and the new generative design process, provide effective solutions for design engineers in more and more industrial application areas. Experience shows that modern design methods can be used in many areas of industry. The appearance of metal powder printing and additive technology make it possible to test the designed prototypes or even to produce the final products. The following article aims to support the above with the help of a case study.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"24 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85488233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"online bankolás hazai vizsgálata","authors":"D. Varga, Virág Kiss","doi":"10.21791/ijems.2023.1.4.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.4.","url":null,"abstract":"Napjainkban a digitalizáció térhódítása folyamatosan nő. A jelenlegi felnövekvő generáció már „digitális bennszülött”. A digitalizáció részeként feltétlenül említést kell tennünk az internetről, ami kiemelt szerepet tölt be mindennapi életünkben. Az interneten keresünk információt, kommunikálunk, vásárolunk. Ezen tényezők és a 2020-ban kialakult pandémia miatt az internetes ügyintézés is kiemelt fontosságúvá vált. A bankoknak folyamatosan alkalmazkodniuk kell a megnövekedett igényekhez, amik a kényelmes, otthoni bankolást segítik elő. Kutatásunk során éppen erre a folyamatos alkalmazkodásra, és az ebből eredő fejlesztésekre koncentráltunk. A kutatás középpontjában a hazai nagybankok internet- és mobilbankjai álltak. A mintavételezés 2 időszakban zajlott. A primer kutatási eszközök közül a dokumentumelemzést és a netnográfiát választottuk. A kutatás során összehasonlítottuk a platformokon elérhető funkciókat, a mobilbankok fogyasztói megítélését és más változókat. A kutatás során kapott eredmények alapján megállapítható, hogy a hazai bankok folyamatosan fejlesztik az applikációjukat különböző trendek mentén, és igyekeznek igazodni a változó igényekhez. A legtöbb nagybank mobilbankjában komoly változásokat kellett megvalósítani, akár korábbi mobilbankjuk végleges kivezetésével. A változások erős hatást gyakorolhatnak a fogyasztókra, akikből ezen változások gyakran inkább negatív véleményt váltottak ki. Összességében a digitalizálódás ilyetén formája kiemelten fontos ezen szektorban is.  A tanulmány a Tudományos Diákköri Konferenciára készült pályamunka részleteit tartalmazza.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"16 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78007723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Full-Scale Tests of Pipeline Girth Welds Under Complex Cyclic Internal Pressure and Static Bending Loading Conditions","authors":"A. Y. Dakhel, J. Lukács","doi":"10.21791/ijems.2023.1.10.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.10.","url":null,"abstract":"The critical elements of high-pressure hydrocarbon transporting pipelines are often the girth welds, which are subjected to complex loads. The aims of our research and this paper are to introduce our full-scale pipeline fatigue and burst tests applying cyclic internal pressure and superimposed external bending stress on girth welds, furthermore, attracting the importance and the applicability of the investigation results. A unique testing system was built to study the behaviour of pipeline girth welds under simultaneous loads. The tests were evaluated using video camera recordings, internal pressure vs. burst time functions and failure pressure values.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"119 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85700474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Modelling and Simulation of Sheet Metal Forming Process","authors":"Marwen Habbachi, A. Baksa","doi":"10.21791/ijems.2023.1.1.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.1.","url":null,"abstract":"Simulation and modelling of sheet metal forming process are well common today in different industries (automotive, aerospace) and several research centers regarding its huge impact for both on production and reliability of the lifecycle of the equipment, and the quality of the product. However, to obtain the best configuration possible with the inputs parameters to achieve high level of production and increasing the durability of the tools needs some extra methods for the optimization for this problem using mostly finite element method cooperated with iterative algorithms based on Artificial Neural Network (ANN) [1]. Whereas this research is focused on modelling of stamping process of stainless steel AISI 304 to investigate to formability of the material, and studying the influence of the friction factor on the quality of the product as well the energy required for each set configuration.\u0000 ","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"7 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86927447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficiency of the Machining Process of Circular Shapes by Electrical Discharge Technology","authors":"Ľ. Straka, P. Kuchta","doi":"10.21791/ijems.2023.1.7.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.7.","url":null,"abstract":"Due to its high machining precision, EDM technology is nowadays very important in the production of high-precision parts for various industries. The high precision of the machined surface in combination with the ability to machine circular surfaces brings, in addition to several advantages, some negatives. The most significant negative of this machining technology is the relatively low productivity as well as the overall production efficiency. The latter is affected by many accompanying phenomena. The main accompanying phenomenon that contributes to the decline in the overall economic efficiency of EDM is the microgeometry errors that occur due to the non-homogeneity of the EDM process. Another accompanying negative phenomenon is the geometric accuracy errors of the machined surface, as a consequence of systematic destruction of the wire tool electrode, faulty interpolation in its guidance, and, last but not least, its vibration. These aspects consequently lead to the requirement for multiple applications of additional finishing cuts, which significantly reduces the overall economic efficiency of the machining process. Therefore, the experimental research aimed to search for options that can effectively help to achieve higher productivity but especially the overall economic efficiency of the machining process.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89134417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical Testing of 3D Metal Printed Stainless Steel Specimens","authors":"S. Kovács, L. Varga","doi":"10.21791/ijems.2023.1.2.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.2.","url":null,"abstract":"Additive manufacturing (AM) is a cutting-edge production method, which has come a long way since its first introduction in the ’80s. Back in the days its usage was very limited to stereolithography, and was only able to make weak structures, so it only worked for visualization. Four decades later it is one of the leading research fields in production areas, because of its flexibility and its ability to make almost any complex geometry. However, no matter how powerful it is, it is not omnipotent, there are certain size and shape restrictions even this method must apply to.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"30 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74565063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dunning–Kruger Effect in Knowledge Management Examination of BSc Level Business Students","authors":"A. Kun, C. Juhász, J. Farkas","doi":"10.21791/ijems.2023.1.3.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.3.","url":null,"abstract":"The Dunning-Kruger effect (DKE) in higher education evaluation is one of the current research areas of psychology, educational science, and management science (in our case). Its importance is that the less prepared one is, the less accurately one can judge what performance is expected of him. What is more, he will err more and will overestimate himself. The present study aims better to understand the phenomenon with new, small-sample empirical results. The study is part of a research series that has been ongoing at the University of Debrecen since 2015. It not only quantitatively expands the literature but also includes the course of Knowledge Management among those examined. During the research, students were asked both before the examination (N = 63) and after the examination (N = 76) to guess how many points they would achieve on a multiple-choice test. It supports the presence of DKE, both in the case of pre-examination and post-examination self-evaluations. Using four multivariate linear regression models, we examined whether the sign value or absolute value of the errors made during the guesses show a correlation - in addition to the available control variables - with the test score. Our results showed that the more accurate the pre-examination and post-examination estimations were, the higher the students' actual score was, while the less they tended to overestimate their preparation. This supports the presence of DKE, both in the case of pre-exam and post-exam self-evaluation.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"81 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84128190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of BLDC Motor Drive Systems for Electric Vehicles Using Matlab Simulink","authors":"Nemes Dániel, S. Hajdu","doi":"10.21791/ijems.2023.1.6.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.6.","url":null,"abstract":"The defining scientific developments of our time would not have been possible without the use of simulations. The aim of the research is to create a simulation of a BLDC motor. When creating a simulation, great emphasis must be placed on defining the purpose of the simulation. This basically determines the structure and complexity of the model. The model discussed here was created so that an optimization task could be defined more precisely by inserting it as a sub-model into a vehicle dynamics model. Scalability was another aspect, that is, to be able to increase the accuracy of the model with measured data in the future, as well as to be able to validate it. During the research, a BLDC motor efficiency map generation program was created, as well as an environment for testing the generated data. The created system gives researchers the opportunity to use a shape-correct efficiency model when simulating a BLDC motor even without measured data. This makes it possible to discover real relationships between model parameters when performing optimization.\u0000 ","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"59 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79575472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Viselhető technológia használat a Debreceni Egyetem hallgatói körében","authors":"Gergely Ráthonyi, Kinga Ráthonyi-Ódor, G. Szabados, Z. Bács, Éva Bácsné Bába","doi":"10.21791/ijems.2023.1.5.","DOIUrl":"https://doi.org/10.21791/ijems.2023.1.5.","url":null,"abstract":"Világszerte sürgető közegészségügyi probléma a fizikai aktivitás hiánya, az ülő életmód széleskörű elterjedése. A probléma jellemző a fiatal populációra is, kiemelten az egyetemistákra, akik idejük jelentős részét töltik üléssel. A technológiai fejlődés egyik katalizátora a mozgásszegény életmód térnyerésének, ugyanakkor ennek köszönhetően számos olyan eszköz jelent meg a piacon, mely éppen a fizikai aktivitás ösztönzésére is szolgálhat. Folyamatosan növekvő tendenciát mutat a fizikai aktivitást mérő viselhető technológiai eszközök – karóra, karpánt – elterjedése a lakosság körében, mellyel párhuzamosan növekszik a magunkról gyűjtött adatok (lépésszám, elégetett kalória, pulzus) mennyisége is. A szerzők témaválasztását az indokolja, hogy a hazai sporttudomány területén kevés olyan tanulmánnyal találkozhatunk, mely napjaink korszerű információtechnológia eszközeit helyezi a fókuszába a fizikai aktivitás dimenziójában. Jelen tanulmány célja, hogy az egyetemista populáció körében felmérje az aktivitást mérő viselhető eszközökkel kapcsolatos attitűdöket. Keresztmetszeti kutatásunk során online kvantitatív kérdőíves felmérést végeztünk a DE GTK hallgatói körében. A kérdőívet 340 fő töltötte ki megfelelően. A leíró statisztika mellett az összefüggések vizsgálatakor paraméteres és nem paraméteres próbákat alkalmaztunk (Pearson-féle khí négyszet próba, Fisher féle egzakt próba, t-próba). A statisztikai próbák eredményeit p<0,05 esetén tekintettük szignifikánsnak. Kolgomorov-Smirnov teszttel vizsgáltuk a változók eloszlását. A megkérdezettek többsége (55%) kipróbált már valamilyen viselhető, fizikai aktivitást mérő eszközt. Harmaduk (34%) jelenleg is használja az eszközét. Akik eddig nem próbálták ki ezeket az eszközöket az árat jelölték meg elsődleges visszatartó tényezőként. Harmaduk tervezi, hogy beruház egy ilyen eszközre a jövőben. Az eszközt használók 39%-a aktivitásmérő karkötőt, míg 61%-uk okosórát használ, vagy használt korábban. Nemek tekintetében nem találtunk eltérést az eszközök tulajdonlását tekintve. A megkérdezett aktivitást mérő eszközt viselő fiatalok 66,8%-nak a fizikai aktivitásának követése volt az elsődleges célja. A leggyakrabban használt funkció a lépésszám követése volt, a megkérdezettek 81%-a jelölte, ezt követte a pulzusszám mérése (67%). Legtöbben a lépésszámukkal kapcsolatban (69%) határoztak meg valamilyen célkitűzést. Minden harmadik hallgató szerint az eszköz hatására többet mozgott és sikerült fenntartania az emelt mozgás szintjét. A hallgatók 44%-a állította, hogy a fizikai aktivitása nem változott az eszköz használatának ellenére sem. A megkérdezettek inkább nem értenek egyet a felsorolt pozitív élettani hatásokkal az eszközök viselésével kapcsolatban. Kutatásunkban is érezhető, hogy a viselhető eszközök hatással vannak a fiatalokra, nyomonkövetik saját adataikat ugyanakkor megkérdőjelezhető, hogy az eszközök önmagukban elég ösztönző hatásúak-e a hallgatók számára az egészségesebb életmód kialakításában.","PeriodicalId":44185,"journal":{"name":"International Journal of Mathematical Engineering and Management Sciences","volume":"45 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2023-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89197221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}