Search results for: structured roughness

Authors: Vaclav Musil, Robert Cep, Sarka Malotova, Jiri Hajnys, Frantisek Spalek

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The new designs of satellite gears comprising a number of small gears pose high requirements on the precise production of small module gears. The objective of the experimental activity stated in this article was to compare the conventional rolling gear cutting technology with the modern wire electrical discharge machining (WEDM) technology for the production of small module gear m=0.6 mm (thickness of 2.5 mm and material 30CrMoV9). The WEDM technology lies in copying the profile of gearing from the rendered trajectory which is then transferred to the track of a wire electrode. During the experiment, we focused on the comparison of these production methods. Main measured parameters which significantly influence the lifetime and noise was chosen. The first parameter was to compare the precision of gearing profile in respect to the mathematic model. The second monitored parameter was the roughness and surface topology of the gear tooth side. The experiment demonstrated high accuracy of WEDM technology, but a low quality of machined surface.

Keywords: precision of gearing, small module gears, surface topology, WEDM technology

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Authors: Sergio Luiz da Costa Junior, Carolina Fofonka Palomino, Paulo Cesar Lodi

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The use of light landfills is an effective solution for road works in soft ground sites, such as Rio de Janeiro (RJ) and Santos (SP) - the Southeastern Brazilian coast. The technique consists in replacing the topsoil by expandable polystyrene (EPS) geofoam, lined with geomembrane to prevent the attack of chemical products.Thus, knowing the interface shear strength of those materials is important in projects to avoid rupturing the system. The purpose of this paper is to compare the shear strength in the geomembrane-EPS interfaces by the direct shear test. The tests were performed under the dry and saturated condition, and four kind of high-density polyethylene (HDPE) 2,00mm geomembranes were used, smooth and texturized - manufactured in the flat die and blown film process. It was found that the shear strength is directly influenced by the roughness of the geomembrane, showed higher friction angle in the textured geomembrane. The direct shear test, in the saturated condition, also showed smaller friction angle than the now-wetted test.

Keywords: geofoam, geomembrane, soft ground, strength shear

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Authors: Charles Davidson

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This paper presents the Stoplight Analysis System of Partnering Organizations Readiness, offering a structured framework to evaluate conflict resolution collaboration feasibility, especially crucial in conflict areas, employing a colour-coded approach and specific assessment points, with implications for more informed decision-making and improved outcomes in peacebuilding initiatives. Derived from at total of 40 years of practical peacebuilding experience from the project’s two researchers as well as interviews of various other peacebuilding actors, this paper introduces the Stoplight Analysis System of Partnering Organizations Readiness, a comprehensive framework designed to facilitate effective collaboration in international/local peacebuilding partnerships by evaluating the readiness of both potential partner organisations and the location of the proposed project. ^The system employs a colour-coded approach, categorising potential partnerships into three distinct indicators: Red (no-go), Yellow (requires further research), and Green (promising, go ahead). Within each category, specific points are identified for assessment, guiding decision-makers in evaluating the feasibility and potential success of collaboration. The Red category signals significant barriers, prompting an immediate stoppage in the consideration of partnership. The Yellow category encourages deeper investigation to determine whether potential issues can be mitigated, while the Green category signifies organisations deemed ready for collaboration. This systematic and structured approach empowers decision-makers to make informed choices, enhancing the likelihood of successful and mutually beneficial partnerships. Methodologically, this paper utilised interviews from peacebuilders from around the globe, scholarly research of extant strategies, and a collaborative review of programming from the project’s two authors from their own time in the field. This method as a formalised model has been employed for the past two years across a litany of partnership considerations, and has been adjusted according to its field experimentation. This research holds significant importance in the field of conflict resolution as it provides a systematic and structured approach to peacebuilding partnership evaluation. In conflict-affected regions, where the dynamics are complex and challenging, the Stoplight Analysis System offers decision-makers a practical tool to assess the readiness of partnering organisations. This approach can enhance the efficiency of conflict resolution efforts by ensuring that resources are directed towards partnerships with a higher likelihood of success, ultimately contributing to more effective and sustainable peacebuilding outcomes.

Keywords: collaboration, conflict resolution, partnerships, peacebuilding

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Authors: Ali Ballouch, Nourelhouda Choukri, Zouhair Soufiani, Mohamed El Jouad, Mohamed Addou

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For several years, significant research has been developed in the areas of applications of semiconductor wide bandgap such as ZnO in optoelectronics. This oxide has the advantage of having a large exciton energy (60 meV) three times higher than that of GaN (21 meV) or ZnS (20 meV). This energy makes zinc oxide resistant for laser irradiations and very interesting for the near UV-visible optic, as well as for studying physical microcavities. A high-energy direct gap at room temperature (Eg > 1 eV) which makes it a potential candidate for emitting devices in the near UV and visible. Our work is to study the nonlinear optical properties, mainly the nonlinear third-order susceptibility of europium doped Zinc oxide thin films. The samples were prepared by chemical vapor spray method (Spray), XRD, SEM technique, THG were used for characterization. In this context, the influence of europium doping on the nonlinear optical response of the Zinc oxide was investigated. The nonlinear third-order properties depend on the physico-chemical parameters (crystallinity, strain, and surface roughness), the nature and the level of doping, temperature.

Keywords: ZnO, characterization, non-linear optical properties, optoelectronics

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Authors: Mohiuddin Sakib, Fatin Nihal, Anisul Haque, Munsur Rahman, Mansur Ali

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Sundarban, the largest mangrove forest in the world, is known to act as a buffer against the cyclone and storm surge. Theoretically, Sundarban absorbs the initial thrust of the wind and acts to ‘resist’ the storm surge flooding. The role of Sundarban was evident during the cyclone Sidr when the Sundarban solely defended the initial thrust of the cyclonic wind and the resulting storm surge inundation. In doing this, Sundarban sacrificed 30% of its plant habitats. Although no scientific study has yet been conducted, it is generally believed that Sundarban will continuously play its role as a buffer against the cyclone when landfall of the cyclone is at or close to the Sundarban. Considering these facts, the present study mainly focused on a scientific insight into the role of Sundarban as a buffer against the present-day cyclone and storm surge and also its probable role on the impacts of future storms of similar nature but with different landfall locations. The Delft 3D dashboard and flow model are applied to compute the resulting inundation due to cyclone induced storm surge. The results show that Sundarban indeed acts as a buffer against the storm surge inundation when cyclone landfall is at or close to Sundarban.

Keywords: buffer, Mangrove forest, Sidr, landfall, roughness

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Authors: Moet Moet Myint Lay

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Continuing professional development involves acquiring new knowledge and skills for current work and improving career opportunities in the field through continuing education (OECD, 2000). This article examines the effectiveness of CPD in improving teacher quality and the resulting need for CPD for teacher educators in Myanmar. The purpose of this study is to explore a deeper understanding of teacher-to-teacher continuing professional development in improving teacher education programs. Research questions: (1) How do teachers in Myanmar understand the idea of continuous professional development for professional development? (2) What CPD activities are required for all teachers in teachers' colleges? (3) What are the main challenges of CPD implementation in Myanmar Education College? A qualitative method using semi-structured interviews was used in this study. Seven teacher educators from Mandalay Education College participated in this study. There are three male teacher educators and four female teacher educators. All participants who responded to the semi-structured interviews were between 29 and 45 years old.The interviews revealed that professional development involves acquiring the necessary pedagogical knowledge and skills to encourage students to think creatively and critically. Teachers must participate in a variety of activities, including professional interviews, lesson study, training programs, workshops, and seminars. All results showed that teachers need English and ICT skills for teaching and learning, including extended ICT courses for those who have completed a foundation course, access to e-libraries, and inclusive education (including language teaching and learning), facilitate the assessment (formative and summative), practicum, mentoring, and coaching skills. The study concludes with practical findings that suggest an urgent need for CPD activities for teachers.

Keywords: continuous professional development, teacher educator, teacher training program), mentoring

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Authors: Guru Prakash, Revanth Dugalam

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A road’s condition often deteriorates due to harsh loading such as overload due to trucks, and severe environmental conditions such as heavy rain, snow load, and cyclic loading. In absence of proper maintenance planning, this results in potholes, wide cracks, bumps, and increased roughness of roads. In this paper, a data-driven model will be developed to detect these damages using vibration and image signals. The key idea of the proposed methodology is that the road anomaly manifests in these signals, which can be detected by training a machine learning algorithm. The use of various machine learning techniques such as the support vector machine and Radom Forest method will be investigated. The proposed model will first be trained and tested with artificially simulated data, and the model architecture will be finalized by comparing the accuracies of various models. Once a model is fixed, the field study will be performed, and data will be collected. The field data will be used to validate the proposed model and to predict the future road’s health condition. The proposed will help to automate the road condition monitoring process, repair cost estimation, and maintenance planning process.

Keywords: SVM, data-driven, road health monitoring, pot-hole

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Authors: R. Oleko, A. Saraceni

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The aim of this research is to provide a rigorous evaluation of the existing academic productivity in relation to value proposition and creation in networked environments. Bibliometrics is a vigorous approach used to structure existing literature in an objective and reliable manner. To that aim, a thorough bibliometric analysis was performed in order to assess the large volume of the information encountered in a structured and reliable manner. A clear distinction between networks and service networks was considered indispensable in order to capture the effects of each network’s type properties on value creation processes. Via the use of bibliometric parameters, this review was able to capture the state-of-the-art in both value proposition and value creation consecutively. The results provide a rigorous assessment of the annual scientific production, the most influential journals, and the leading corresponding author countries. By means of citation analysis, the most frequently cited manuscripts and countries for each network type were identified. Moreover, by means of co-citation analysis, existing collaborative patterns were detected through the creation of reference co-citation networks and country collaboration networks. Co-word analysis was also performed in order to provide an overview of the conceptual structure in both networks and service networks. The acquired results provide a rigorous and systematic assessment of the existing scientific output in networked settings. As such, they positively contribute to a better understanding of the distinct impact of service networks on value proposition and value creation when compared to regular networks. The implications derived can serve as a guide for informed decision-making by practitioners during network formation and provide a structured evaluation that can stand as a basis for future research in the field.

Keywords: bibliometrics, co-citation analysis, networks, service networks, value creation, value proposition

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Authors: Kubra Akbayrak

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In parallel with increasing inclusive practice for pupils with vision impairments, the role of specialist teachers who have specialized in the area of vision impairment has dramatically changed in recent years. This study, therefore, aims to provide a holistic perspective towards the distinctive role of specialist teachers of pupils with vision impairments in different educational settings (including mainstream settings, special school settings, etc.) in Turkey and England. Within the scope of the study, semi-structured interviews have been conducted with 17 specialist teachers in Turkey and 14 specialist teachers in England in order to reveal the perception of specialist teachers regarding their roles in different educational settings as well as their perception towards their pre-service training. As this study is a part of an ongoing PhD research, the qualitative data through semi-structured interviews will be analyzed through using Bronfenbrenner’s ecological systems theory as a theoretical framework in order to provide a holistic view regarding the role of specialist teachers particularly in facilitating curriculum access for pupils with vision impairments in England and Turkey. However, the initial findings broadly illustrate that specialist teachers who work in special school settings have different understanding regarding their roles compared to specialist teachers who work in mainstream settings in relation to promoting independence for pupils with vision impairments. The initial findings also imply that specialist teachers in England and Turkey have different perception about their roles in relation to providing specialist advice and guidance for families of pupils. With the completion of the analysis of the study, it is hoped that the findings will provide an insight into the role of specialist teachers in order to provide implication for programmes which prepare specialist teachers of pupils with vision impairments.

Keywords: curriculum access, pupils with vision impairments, specialist teachers, special education

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Authors: Malathi Balakrishnan, Cheng Lee Ooi, Chander Vengadasalam

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The purpose of this study is to explore a case study of trainee teachers’ learning experience on innovating traditional games during the traditional game carnival. It explores issues arising from multiple case studies of trainee teachers learning experiences in innovating traditional games. A qualitative methodology was adopted through observations, semi-structured interviews and reflective journals’ content analysis of trainee teachers’ learning experiences creating and implementing innovative traditional games. Twelve groups of 36 trainee teachers who registered for Sports and Physical Education Management Course were the participants for this research during the traditional game carnival. Semi structured interviews were administrated after the trainee teachers learning experiences in creating innovative traditional games. Reflective journals were collected after carnival day and the content analyzed. Inductive data analysis was used to evaluate various data sources. All the collected data were then evaluated through the Nvivo data analysis process. Inductive reasoning was interpreted based on the Self Determination Theory (SDT). The findings showed that the trainee teachers had positive game participation experiences, game knowledge about traditional games and positive motivation to innovate the game. The data also revealed the influence of themes like cultural significance and creativity. It can be concluded from the findings that the organized game carnival, as a requirement of course work by the Institute of Teacher Training Malaysia, was able to enhance teacher trainers’ innovative thinking skills. The SDT, as a multidimensional approach to motivation, was utilized. Therefore, teacher trainers may have more learning experiences using the SDT.

Keywords: learning experiences, innovation, traditional games, trainee teachers

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Authors: Daniel Panario, Daniel Santana de Freitas, Brett Stevens

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Almost Perfect Nonlinear (APN) permutations with optimal resistance against differential cryptanalysis can be found in several domains. The permutation used in the standard for symmetric cryptography (the AES), for example, is based on a special kind of inversion in GF(28). Although very close to APN (2-uniform), this permutation still contains one number 4 in its differential spectrum, which means that, rigorously, it must be classified as 4-uniform. This fact motivates the search for fully APN permutations in other domains of definition. The extremely high complexity associated to this kind of problem precludes an exhaustive search for an APN permutation with 256 elements to be performed without the support of a suitable mathematical structure. On the other hand, in principle, there is nothing to indicate which mathematically structured domains can effectively help the search, and it is necessary to test several domains. In this work, the search for APN permutations in rings ℤ2×ℤ2k is investigated. After a full, exhaustive search with k=2 and k=3, all possible APN permutations in those rings were recorded, together with their differential profiles. Some very promising heuristics in these cases were collected so that, when used as a basis to prune backtracking for the same search in ℤ2×ℤ8 (search space with size 16! ≅244), just a few tenths of a second were enough to produce an APN permutation in a single CPU. Those heuristics were empirically extrapolated so that they could be applied to a backtracking search for APNs over ℤ2×ℤ16 (search space with size 32! ≅2117). The best permutations found in this search were further refined through Simulated Annealing, with a definition of neighbors suitable to this domain. The best result produced with this scheme was a 3-uniform permutation over ℤ2×ℤ16 with only 24 values equal to 3 in the differential spectrum (all the other 968 values were less than or equal 2, as it should be the case for an APN permutation). Although far from being fully APN, this result is technically better than a 4-uniform permutation and demanded only a few seconds in a single CPU. This is a strong indication that the use of mathematically structured domains, like the rings described in this work, together with heuristics based on smaller cases, can lead to dramatic cuts in the computational resources involved in the complexity of the search for APN permutations in extremely large domains.

Keywords: APN permutations, heuristic searches, symmetric cryptography, S-box design

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Authors: Amol M. Jadhav, Sharad S. Chudhari, S. S. Khedkar

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This review presents a through survey of research paper work on the experimental analysis, FEM Analysis & simulation of the metal spinning process. In this literature survey all the papers being taken from Elsevier publication and most of the from journal of material processing technology. In a last two decade or so, metal spinning process gradually used as chip less formation for the production of engineering component in a small to medium batch quantities. The review aims to provide include into the experimentation, FEM analysis of various components, simulation of metal spinning process and act as guide for research working on metal spinning processes. The review of existing work has several gaps in current knowledge of metal spinning processes. The evaluation of experiment is thickness strain, the spinning force, the twisting angle, the surface roughness of the conventional & shear metal spinning process; the evaluation of FEM of metal spinning to path definition with sufficient fine mesh to capture behavior of work piece; The evaluation of feed rate of roller, direction of roller,& type of roller stimulated. The metal spinning process has the more flexible to produce a wider range of product shape & to form more challenge material.

Keywords: metal spinning, FEM analysis, simulation of metal spinning, mechanical engineering

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Authors: Raghad Abu Salma, Beatrice Szczepek Reed

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Politeness is one of the most researched areas in pragmatics as it is key to interpersonal interactional phenomena. Many studies, particularly in linguistics, have focused on developing politeness theories and exploring linguistic devices used in communication to construct and establish social norms. However, the question of what constitutes polite language remains a point of ongoing debate. Prior research primarily examined politeness in English and its native speaking communities, oversimplifying the notion of politeness and associating it with surface-level language use. There is also a dearth of literature on politeness in Arabic, particularly in the context of Jordanian Arabic. Prior research investigating politeness in Arabic make generalized claims about politeness in Arabic without taking the linguistic variations into account or providing empirical evidence. This proposed research aims to explore how Jordanian Arabic influences its first language users in making and responding to requests, exploring participants' perceptions of politeness and the linguistic choices they make in their interactions. The study focuses on Jordanian expats living in London, UK providing an intercultural perspective that prior research does not consider. This study employs a mixed-methods approach combining discourse completion tasks (DCTs) with semi-structured interviews. While DCTs provide insight into participants’ linguistic choices, semi-structured interviews glean insight into participants' perceptions of politeness and their linguistic choices impacted by cultural norms and diverse experiences. This paper discusses previous research on politeness in Arabic, identifies research gaps, and discusses different methods for data collection. This paper also presents preliminary findings from the ongoing study.

Keywords: politeness, pragmatics, jordanian arabic, intercultural politeness

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Authors: Mohamed S. Selim, Nesreen A. Fatthallah, Shimaa A. Higazy, Zhifeng Hao, Xiang Chen

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After the prohibition of tin-based fouling-prevention coatings in 2003, the researchers were directed toward eco-friendly coatings. Because of their nonstick, environmental, and economic benefits, foul-release nanocoatings have received a lot of attention. They use physical anti-adhesion terminology to deter any fouling attachment.Natural bioinspired surfaces have micro/nano-roughness and low surface free energy features, which may inspire the design of dynamic antifouling coatings. Graphene-based nanocomposite surfaces were designed to combat marine-fouling adhesion with ecological as well as eco-friendly effects rather than biocidal solutions. Polymer–graphenenanofiller hybrids are a novel class of composite materials in fouling-prevention applications. The controlled preparation of nanoscale orientation, arrangement, and direction along the composite building blocks would result in superior fouling prohibition. This work representsfoul-release nanocomposite top coats for marine coating applications with superhydrophobicity, surface inertness against fouling adherence, cost-effectiveness, and increased lifetime.

Keywords: foul-release nanocoatings, graphene-based nanocomposite, polymer, nanofillers

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Authors: Tae An Kim, Hyo Lim Kang, Hye Won Han, Seung Ho Han

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The drive shaft of passenger vehicle has its own function such as transmitting the engine torque from the gearbox and differential gears to the wheels. It must also compensate for all variations in angle or length resulting from manoeuvring and deflection for perfect synchronization between joints. Torsional fatigue failures occur frequently at the connection parts of the spline joints in the end of the drive shaft. In this study, the fatigue life of a drive shaft of passenger vehicle was estimated by using the finite element analysis. A commercial software of n-Code was applied under twisting load conditions, i.e. 0~134kgf•m and 0~188kgf•m, in which the shear strain range-fatigue life relationship considering Signed Shear method, Smith-Watson-Topper equation, Neuber-Hoffman Seeger method, size sensitivity factor and surface roughness effect was taken into account. The estimated fatigue life was verified by a twisting load test of the real drive shaft in a test rig. (Human Resource Training Project for Industry Matched R & D, KIAT, N036200004).

Keywords: drive shaft, fatigue life estimation, passenger vehicle, shear strain range-fatigue life relationship, torsional fatigue failure

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Authors: Abu Saleh Mohammad Sowad

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Back in history, muscular and strong male body has always been used to promulgate masculinity; for physically representing supreme manliness there were not many other options. This idealized male figure was proliferated mainly for spreading the notion of male superiority in relation to power and to give a strong base to the social construction of masculinity. This study targets to disclose the perception about the attributes masculinities among the male students of Dhaka city regarding male beautification. It is an attempt to unveil young men’s perspectives regarding their masculinities and beauty. Till the very recent past, beauty was always seen as sole feminine trait in Bangladeshi society. From history we can see men have always been assumed as the ambassador of roughness but in recent time the emergence of fashion-conscious men can be seen, who are slowly occupying a handsome position in the society. Concerning study attempts to bring out the way in which such changing trend of male beauty is perceived among the male students of Dhaka city. What could be the ideologies of these young men who are being involved with it? What is influencing them to be part of such arena which, to a great extent, is still considered as female domain? Is their perception about construction of masculinity is shifting from the so called idealized masculinity? The study tries to find out the answers.

Keywords: masculinity, male beauty, Bangladesh, identity, body

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Authors: E. Y. Igde, S. Aydogan, F. E. Boran, D. Akay

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Patent data have an increasingly important role in economic growth, innovation, technical advantages and business strategies and even in countries competitions. Analyzing of patent data is crucial since patents cover large part of all technological information of the world. In this paper, we have used the linguistic summarization technique to prove the validity of the hypotheses related to patent data stated in the literature.

Keywords: data mining, fuzzy sets, linguistic summarization, patent data

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Authors: Sajjad Esmaeili, Robert Krause, Lukas Gerlich, Alireza Mohammadian Kia, Benjamin Uhlig

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This investigation aims to develop the feasible and qualitative process parameters for the thin films fabrication into ultra-large through-silicon-vias (TSVs) as vertical interconnections. The focus of the study is on TSV metallization and its challenges employing new materials for the purpose of rapid signal propagation in the microsystems technology. Cobalt metal-organic chemical vapor deposition (Co-MOCVD) process enables manufacturing an adhesive and excellent conformal ultra-thin film all the way through TSVs in comparison with the conventional non-conformal physical vapor deposition (PVD) process of copper (Cu) seed layer. Therefore, this process provides a Cu seed-free layer which is capable of direct Cu electrochemical deposition (Cu-ECD) on top of it. The main challenge of this metallization module is to achieve the proper alternative seed layer with less roughness, sheet resistance and granular organic contamination (e.g. carbon) which intensify the Co corrosion under the influence of Cu electrolyte.

Keywords: Cobalt MOCVD, direct Cu electrochemical deposition (ECD), metallization technology, through-silicon-via (TSV)

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Authors: Kristiina Teiss

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Estonians and children having Estonian as a one of their languages have lately become the fastest growing minority or bilingual group in Finland which underlines the importance of studying this target group. The acquisition of bilingualism by an infant is affected by many different issues like the child’s personal traits, language differences, and different environmental factors such as people´s attitudes towards languages and bilingualism. In the early years the most important factor is the children’s interaction with their parents and siblings. This poster gives an overview to the material and some preliminary findings of ongoing PhD study concerning code-mixing, code-switching and language attitudes of two bilingual 10-11 year old children. Data was collected from two different bilingual families, one of them living in Tampere, Finland and one of them moved during the study to Tallinn, Estonia. The data includes audio recordings of the families’ interactions with their children when they were aged 2-3 years old and then when they were 10-11 years old. The data also includes recorded semi-structured queries of the parents, as well as recorded semi-structured queries of the children when they were in the age of 10-11 years. The features of code-mixing can vary depending on norms or models in the families, or even according to its use by two parents in same family. The practices studied in the ongoing longitudinal case study, based on a framework of ethnography, contain parental conversational strategies and family attitudes as well as CS (code-switching and code-mixing) cases occurring both in children and adult language. The aim of this paper is to find out whether there is a connection between children’s attitudes and their daily language use. It would be also interesting to find some evidence, as to whether living in different countries has different impacts on using two languages. The results of dissertation maid give some directional suggestions on how language maintenance of Estonian-Finnish bilinguals could be supported, although generalizations on the base of case study could not be done.

Keywords: code switching, Estonian, Finnish, language attitudes

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Authors: B. Ravi Kumar, S. Gajanana, K. Hemachandra Reddy, K. Udayani

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Physically into various derived shapes and sizes under the effect of externally applied forces. The spinning process is an advanced plastic working technology and is frequently used for manufacturing axisymmetric shapes. Over the last few decades, Sheet metal spinning has developed significantly and spun products have widely used in various industries. Nowadays the process has been expanded to new horizons in industries, since tendency to use minimum tool and equipment costs and also using lower forces with the output of excellent surface quality and good mechanical properties. The automation of the process is of greater importance, due to its wider applications like decorative household goods, rocket nose cones, gas cylinders, etc. This paper aims to gain insight into the conventional spinning process by employing experimental and numerical methods. The present work proposes an approach for optimizing process parameters are mandrel speed (rpm), roller nose radius (mm), thickness of the sheet (mm). Forming force, surface roughness and strain are the responses.in spinning of Aluminum (2024-T3) using DOE-Response Surface Methodology (RSM) and Analysis of variance (ANOVA). The FEA software is used for modeling and analysis. The process parameters considered in the experimentation.

Keywords: FEA, RSM, process parameters, sheet metal spinning

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Authors: Juan Carlos Rubio Romero, Francico Salguero Caparros, Virginia Herrera-Pérez

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No one is in the slightest doubt about the high levels of risk involved in work in the construction industry. They are even higher in structural construction work. The Critical Decision Method (CDM) is a semi-structured interview technique that uses cognitive tests to identify the different disturbances that workers have to deal with in their work activity. At present, the vision of safety focused on daily performance and things that go well for safety and health management is facing the new paradigm known as Resilience Engineering. The aim of this study has been to describe the variability in formwork labour on concrete structures in the construction industry and, from there, to find out the resilient attitude of workers to unexpected events that they have experienced during their working lives. For this purpose, a series of semi-structured interviews were carried out with construction employees with extensive experience in formwork labour in Spain by applying the Critical Decision Method. This work has been the first application of the Critical Decision Method in the field of construction and, more specifically, in the execution of structures. The results obtained show that situations categorised as unthought-of are identified to a greater extent than potentially unexpected situations. The identification during these interviews of both expected and unexpected events provides insight into the critical decisions made and actions taken to improve resilience in daily practice in this construction work. From this study, it is clear that it is essential to gain more knowledge about the nature of the human cognitive process in work situations within complex socio-technical systems such as construction sites. This could lead to a more effective design of workplaces in the search for improved human performance.

Keywords: resilience engineering, construction industry, unthought-of situations, critical decision method

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Authors: Kirti Singh, Kesheo Prasad

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A 3D Acoustic Doppler velocimeter was used in the current investigation to quantify the mean and turbulence characteristics in non-uniform open-channel flows. Results are obtained from studies done in the laboratory, analysing the behavior of sand particles under turbulent open channel flow conditions flowing through rough, porous beds. Data obtained from ADV is used to calculate turbulent flow characteristics, Reynolds stresses and turbulent kinetic energy. Theoretical formulations for the distribution of Reynolds stress and the vertical velocity have been constructed using the Reynolds equation and the continuity equation of 2D open-channel flow. The measured Reynolds stress profile and the vertical velocity are comparable with the derived expressions. This study uses the Navier-Stokes equations for analysing the behavior of the vertical velocity profile in the dominant region of full-fledged turbulent flows in open channels, and it gives a new origination of the profile. For both wide and narrow open channels, this origination can estimate the time-averaged primary velocity in the turbulent boundary layer's outer region.

Keywords: turbulence, bed roughness, logarithmic law, shear stress correlations, ADV, Reynolds shear stress

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Authors: Varsha Singh, Kishan Fuse

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This paper presents a study of the grey-Taguchi method to optimize CNC milling parameters of AA6061 T6 aluminium alloy. Grey-Taguchi method combines Taguchi method based design of experiments (DOE) with grey relational analysis (GRA). Multi-response optimization of different quality characteristics as surface roughness, material removal rate, cutting forces is done using grey relational analysis (GRA). The milling parameters considered for experiments include cutting speed, feed per tooth, and depth of cut. Each parameter with three levels is selected. A grey relational grade is used to estimate overall quality characteristics performance. The Taguchi’s L9 orthogonal array is used for design of experiments. MINITAB 17 software is used for optimization. Analysis of variance (ANOVA) is used to identify most influencing parameter. The experimental results show that grey relational analysis is effective method for optimizing multi-response characteristics. Optimum results are finally validated by performing confirmation test.

Keywords: ANOVA, CNC milling, grey relational analysis, multi-response optimization

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Authors: Delna Shroff

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Merchant shipping is an occupation with a high rate of fatal injuries caused by organizational accidents and maritime disasters. In most accident investigations, the leader’s actions are under scrutiny and point out the necessity to investigate the leader’s decisions in critical conditions. While several leadership studies have been carried out in the past, there is a tendency for most research to focus on holders of formal positions. The unit of analysis in most studies has been the ‘individual.’ A need is, therefore, felt to adopt a practice-based perspective of leadership, understand how leadership emerges to affect maritime safety. This paper explores the phenomenon of distributed leadership among seafarers more holistically. It further examines the role of one form of distributed leadership, that is, planfully aligned leadership in the emergency response of the team. A mixed design will be applied. In the first phase, the data gathered by way of semi-structured interviews will be used to explore the seafarer’s implicit understanding of leadership. The data will be used to develop a conceptual framework of distributed leadership, specific to the maritime context. This framework will be used to develop a simulation. Experimental design will be used to examine the relationship between planfully aligned leadership and emergency response of the team members during navigation. Findings show that planfully aligned leadership significantly and positively predicts the emergency response of team members. Planfully aligned leadership leads to a better emergency response of the team members as compared to authoritarian leadership. In the third qualitative phase, additional data will be gathered through semi-structured interviews to further validate the findings to gain a more complete understanding of distributed leadership and its relation to emergency response. Above are the predictive results; the study expects to be a cornerstone of safety leadership research and has important implications for leadership development and training within the maritime industry.

Keywords: authoritarian leadership, distributed leadership, emergency response , planfully aligned leadership

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Authors: Moyera Sanganeria

Abstract:

In the highly competitive landscape of contemporary sports, sportspersons worldwide encounter formidable challenges, often practicing for extensive hours while contending with limited social and physical resources. A growing number of sportspersons globally are sharing their struggles with depression, anxiety, and stress arising from the complex journey and identity associated with being a sportsperson. This qualitative study aims to investigate the challenges faced by sportspersons in individual versus team sports and explore potential gender-based variations in coping strategies. It attempts to do so by recognizing the imperative to comprehend the root causes and coping mechanisms for these stressors. By employing purposive sampling, MMA and Kabaddi players from training academies across Mumbai were selected for the study. Twelve participants were interviewed through semi-structured interviews guided by an interview guide. Reflective thematic analysis was employed to discern diverse stressors and coping strategies. Key stressors encountered by young Indian sportspersons encompass injuries, socio-economic challenges, financial constraints, escalating competition, and performance anxiety. Notably, individuals engaged in team sports tended to adopt emotion-focused coping mechanisms, while those in individual sports leaned more towards problem-focused coping strategies in response to these stressors. There were no prominent gender differences found in coping strategies employed by sportspersons. This study underscores the critical issue of declining mental health among sportspersons in India, emphasizing the necessity for a structured and customized mental health intervention strategy tailored to the unique needs of this population.

Keywords: stressors, coping strategies, sports psychology, sportspersons, mental health

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Authors: Chuan-Ching Sue, Kai-Chun Chuang

Abstract:

Peer-to-Peer (P2P) live streaming systems still suffer a challenge when thousands of new peers want to join into the system in a short time, called flash crowd, and most of new peers suffer long start-up delay. Recent studies have proposed a slot-based user access control mechanism, which periodically determines a certain number of new peers to enter the system, and a user batch join mechanism, which divides new peers into several tree structures with fixed tree size. However, the slot-based user access control mechanism is difficult for accurately determining the optimal time slot length, and the user batch join mechanism is hard for determining the optimal tree size. In this paper, we propose a structured access control (SAC) mechanism, which constructs new peers to a multi-layer mesh structure. The SAC mechanism constructs new peer connections layer by layer to replace periodical access control, and determines the number of peers in each layer according to the system’s remaining upload bandwidth and average video rate. Furthermore, we propose an analytical model to represent the behavior of the system growth if the system can utilize the upload bandwidth efficiently. The analytical result has shown the similar trend in system growth as the SAC mechanism. Additionally, the extensive simulation is conducted to show the SAC mechanism outperforms two previously proposed methods in terms of system growth and start-up delay.

Keywords: peer-to-peer, live video streaming system, flash crowd, start-up delay, access control

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Authors: Danièle Peto

Abstract:

A qualitative research based on twenty-eight semi-structured interviews of students in Social Work, in Brussels (Belgium), showed specific results for the Arab and Muslim students: second and third generations immigrants build their identity on the basis of a mix of differentiation with and recognition of their parents' culture of origin. Building a bridge between Modernity and Tradition, they claim active citizenship; at the same time they show and live by values and religious believes which reinforce the link to their parents’ origins. But they present those values and believes as their own rational choices among other choices, all available and rich for our multicultural society. The way they speak of themselves is highly modern. But, they still have to build a third way to find a place for themselves in society: one allowing them to live their religion as a partially public matter (when the Occidental society leaves no such place for religion) while ensuring, at the same time, the development of independent critical thought. On this basis, other semi-structured interviews are being laid with Social workers working with families from diverse ethnic backgrounds. They will verify the reality of those identity and cultural bricolages when those young adults of second and third generations build their own family. In between the theoretical models of traditional family and modern family, shall we find a new model, hybrid and more or less stable, combining some aspects of the former and the latter? The exploratory research phase focuses on three aspects of building a family life in this context : the way those generations play, discursively or not, in between their parents and the society in which they grew up; the importance of intercultural dialogue in this process of building; and testing the hypothesis that some families, in our society, show a special way of courting Modernity.

Keywords: family models, identity bricolages, intercultural, modernity and tradition

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Authors: Kidus Dawit Gedamu

Abstract:

Addis Ababa City Road Authority is responsible for managing and setting performance evaluation of the city’s road network using the International Roughness Index (IRI). This helps the authority to conduct pavement condition assessments of asphalt roads each year to determine the health status or Level of service (LOS) of the roadway network and plan program improvements such as maintenance, resurfacing and rehabilitation. For a lower IRI limit economical and acceptable maintenance strategy may be selected among a number of maintenance alternatives. The Highway Development and Management (HDM-4) tool can do such measures to help decide which option is the best by evaluating the economic and structural conditions. This paper specifically addresses flexible pavement, including two principal arterial streets under the administration of the Addis Ababa City Roads Authority. The roads include the road from Megenagna Interchange to Ayat Square and from Ayat Square to Tafo RA. First, it was assessed the procedures followed by the city's road authority to develop the appropriate road maintenance strategies. Questionnaire surveys and interviews are used to collect information from the city's road maintenance departments. Second, the project analysis was performed for functional and economic comparison of different maintenance alternatives using HDM-4.

Keywords: appropriate maintenance strategy, cost stream, road deterioration, maintenance alternative

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Authors: Amir Bak Khoshnevis, Mahdieh Khodadadi, Aghil Lotfi

Abstract:

For a bluff body, roughness elements in simulating a turbulent boundary layer, leading to delayed flow separation, a smaller wake, and lower form drag. In the present work, flow past a circular cylinder with using tripping wires is studied experimentally. The wind tunnel used for modeling free stream is open blow circuit (maximum speed = 30m/s and maximum turbulence of free stream = 0.1%). The selected Reynolds number for all tests was constant (Re = 25000). The circular cylinder selected for this experiment is 20 and 400mm in diameter and length, respectively. The aim of this research is to find the optimal operation mode. In this study installed some tripping wires 1mm in diameter, with a different number of wires on the circular cylinder and the wake characteristics of the circular cylinder is studied. Results showed that by increasing number of tripping wires attached to the circular cylinder (6, 8, and 10, respectively), The optimal angle for the tripping wires with 1mm in diameter to be installed on the cylinder is 60̊ (or 6 wires required at angle difference of 60̊). Strouhal number for the cylinder with tripping wires 1mm in diameter at angular position 60̊ showed the maximum value.

Keywords: wake of circular cylinder, trip wire, velocity defect, strouhal number

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Authors: Heroda Gebru, Berhanu Seyoum, Melake Damena, Gezahegn Tesfaye

Abstract:

Background: In Ethiopia there is a population policy aimed at reducing fertility and increasing contraceptive prevalence. Objective: To assess the fertility preference and contraceptive use status of married women who were living in Dire Dawa administrative city. Methods: Cross sectional study which included a sample size of 421 married women of reproductive age were performed. Data was collected using structured questionnaire during house to house survey and semi-structured questionnaire during in-depth interview. Data was processed and analyzed using SPSS version 16 computer software. Univariate, bi variate and multi variate analysis was employed. Results: A total of 421 married women of reproductive age group were interviewed having a response rate of 100 percent. More than half (58.2%) of the respondent have desire of more children. While 41.8% want no more children. Regarding contraceptive use 52.5% of the respondents were using contraceptive at the time of survey. Fertility preference and contraceptive use were significantly associated with age of the respondent, history of child death, number of living children, religion and age at first birth. Conclusions: Those women with younger age group, who had no child death history and women with lesser number of surviving children were more likely desire additional children. Women with older age at first birth and protestant in religion were more likely practiced contraceptive use. Strong information and education regarding contraceptive for younger age group should be provided, advocacy at level of religious leader is important, comprehensive family planning counselling and education should be available for the community, husbands, and religious leaders and the aim for increasing contraceptive use should focus on the practical aspect.

Keywords: fertility preference, contraceptive use, univariate analysis, family planning

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