Search results for: well field layout
7607 Shear Stress and Effective Structural Stress Fields of an Atherosclerotic Coronary Artery
Authors: Alireza Gholipour, Mergen H. Ghayesh, Anthony Zander, Stephen J. Nicholls, Peter J. Psaltis
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A three-dimensional numerical model of an atherosclerotic coronary artery is developed for the determination of high-risk situation and hence heart attack prediction. Employing the finite element method (FEM) using ANSYS, fluid-structure interaction (FSI) model of the artery is constructed to determine the shear stress distribution as well as the von Mises stress field. A flexible model for an atherosclerotic coronary artery conveying pulsatile blood is developed incorporating three-dimensionality, artery’s tapered shape via a linear function for artery wall distribution, motion of the artery, blood viscosity via the non-Newtonian flow theory, blood pulsation via use of one-period heartbeat, hyperelasticity via the Mooney-Rivlin model, viscoelasticity via the Prony series shear relaxation scheme, and micro-calcification inside the plaque. The material properties used to relate the stress field to the strain field have been extracted from clinical data from previous in-vitro studies. The determined stress fields has potential to be used as a predictive tool for plaque rupture and dissection. The results show that stress concentration due to micro-calcification increases the von Mises stress significantly; chance of developing a crack inside the plaque increases. Moreover, the blood pulsation varies the stress distribution substantially for some cases.Keywords: atherosclerosis, fluid-structure interaction, coronary arteries, pulsatile flow
Procedia PDF Downloads 1727606 The Influence of Morphology and Interface Treatment on Organic 6,13-bis (triisopropylsilylethynyl)-Pentacene Field-Effect Transistors
Authors: Daniel Bülz, Franziska Lüttich, Sreetama Banerjee, Georgeta Salvan, Dietrich R. T. Zahn
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For the development of electronics, organic semiconductors are of great interest due to their adjustable optical and electrical properties. Especially for spintronic applications they are interesting because of their weak spin scattering, which leads to longer spin life times compared to inorganic semiconductors. It was shown that some organic materials change their resistance if an external magnetic field is applied. Pentacene is one of the materials which exhibit the so called photoinduced magnetoresistance which results in a modulation of photocurrent when varying the external magnetic field. Also the soluble derivate of pentacene, the 6,13-bis (triisopropylsilylethynyl)-pentacene (TIPS-pentacene) exhibits the same negative magnetoresistance. Aiming for simpler fabrication processes, in this work, we compare TIPS-pentacene organic field effect transistors (OFETs) made from solution with those fabricated by thermal evaporation. Because of the different processing, the TIPS-pentacene thin films exhibit different morphologies in terms of crystal size and homogeneity of the substrate coverage. On the other hand, the interface treatment is known to have a high influence on the threshold voltage, eliminating trap states of silicon oxide at the gate electrode and thereby changing the electrical switching response of the transistors. Therefore, we investigate the influence of interface treatment using octadecyltrichlorosilane (OTS) or using a simple cleaning procedure with acetone, ethanol, and deionized water. The transistors consist of a prestructured OFET substrates including gate, source, and drain electrodes, on top of which TIPS-pentacene dissolved in a mixture of tetralin and toluene is deposited by drop-, spray-, and spin-coating. Thereafter we keep the sample for one hour at a temperature of 60 °C. For the transistor fabrication by thermal evaporation the prestructured OFET substrates are also kept at a temperature of 60 °C during deposition with a rate of 0.3 nm/min and at a pressure below 10-6 mbar. The OFETs are characterized by means of optical microscopy in order to determine the overall quality of the sample, i.e. crystal size and coverage of the channel region. The output and transfer characteristics are measured in the dark and under illumination provided by a white light LED in the spectral range from 450 nm to 650 nm with a power density of (8±2) mW/cm2.Keywords: organic field effect transistors, solution processed, surface treatment, TIPS-pentacene
Procedia PDF Downloads 4477605 Hypothesis about the Origin of the Lighting
Authors: Igor Kuzminov
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Till now, the nature of lightning is not established. A hypothesis of the origin of lightning is proposed. The lightning charge is formed by electromagnetic induction. The role of the conductor is performed by the air mass of the cloud. This conductor moves in the Earth's magnetic field. The upper and lower edges of the cloud are the plates of the capacitor. Lightning is a special case of electromagnetic processes in an atmosphere. The category of lightning occurs in the process of accumulation of a charge. The process of accumulation goes constantly, but the charge is not fixed. Naturally, the hypothesis demands the carrying out of additional experiments and official acknowledgement. As the proof of a hypothesis can serve that the maximal lighting activity in an equatorial zone where cosφ it is close to 1. An experiment conducted privately showed that there is a potential difference in the atmosphere at different levels. The probability of applied value development of power installation is great.Keywords: electromagnetic induction, Earth's magnetic field, plates of the capacitors, charge accumulation
Procedia PDF Downloads 857604 Erasmus+ Program in Vocational Education: Effects of European International Mobility in Portuguese Vocational Schools
Authors: José Carlos Bronze, Carlinda Leite, Angélica Monteiro
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The creation of the Erasmus Program in 1987 represented a milestone in promoting and funding international mobility in higher education in Europe. Its effects were so significant that they influenced the creation of the European Higher Education Area through the Bologna Process and ensured the program’s continuation and maintenance. Over the last decades, the escalating figures of participants and funds instigated significant scientific studies on the program's effects on higher education. More recently, in 2014, the program was renamed “Erasmus+” when it expanded into other fields of education, namely Vocational Education and Training (VET). Despite being now running in this field of education for a decade (2014-2024), its effects on VET remain less studied and less known, while the higher education field keeps attracting researchers’ attention. Given this gap, it becomes relevant to study the effects of E+ on VET, particularly in the priority domains of the Program: “Inclusion and Diversity,” “Participation in Democratic Life, Common Values and Civic Engagement,” “Environment and Fight Against Climate Change,” and “Digital Transformation.” This latter has been recently emphasized due to the COVID-19 pandemic that forced the so-called emergency remote teaching, leading schools to quickly transform and adapt to a new reality regardless of the preparedness levels of teachers and students. Together with the remaining E+ priorities, they directly relate to an emancipatory perspective of education sustained in soft skills such as critical thinking, intercultural awareness, autonomy, active citizenship, teamwork, and problem-solving, among others. Based on this situation, it is relevant to know the effects of E+ on the VET field, namely questioning how international mobility instigates digitalization processes and supports emancipatory queries therein. As an education field that more directly connects to hard skills and an instrumental approach oriented to the labor market’s needs, a study was conducted to determine the effects of international mobility on developing digital literacy and soft skills in the VET field. In methodological terms, the study used semi-structured interviews with teaching and non-teaching staff from three VET schools who are strongly active in the E+ Program. The interviewees were three headmasters, four mobility project managers, and eight teachers experienced in international mobility. The data was subjected to qualitative content analysis using the NVivo 14 application. The results show that E+ international mobility promotes and facilitates the use of digital technologies as a pedagogical resource at VET schools and enhances and generates students’ soft skills. In conclusion, E+ mobility in the VET field supports adopting the program’s priorities by increasing the teachers’ knowledge and use of digital resources and amplifying and generating participants’ soft skills.Keywords: Erasmus international mobility, digital literacy, soft skills, vocational education and training
Procedia PDF Downloads 327603 Investigation of Xanthomonas euvesicatoria on Seed Germination and Seed to Seedling Transmission in Tomato
Authors: H. Mayton, X. Yan, A. G. Taylor
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Infested tomato seeds were used to investigate the influence of Xanthomonas euvesicatoria on germination and seed to seedling transmission in a controlled environment and greenhouse assays in an effort to develop effective seed treatments and characterize seed borne transmission of bacterial leaf spot of tomato. Bacterial leaf spot of tomato, caused by four distinct Xanthomonas species, X. euvesicatoria, X. gardneri, X. perforans, and X. vesicatoria, is a serious disease worldwide. In the United States, disease prevention is expensive for commercial growers in warm, humid regions of the country, and crop losses can be devastating. In this study, four different infested tomato seed lots were extracted from tomato fruits infected with bacterial leaf spot from a field in New York State in 2017 that had been inoculated with X. euvesicatoria. In addition, vacuum infiltration at 61 kilopascals for 1, 5, 10, and 15 minutes and seed soaking for 5, 10, 15, and 30 minutes with different bacterial concentrations were used to artificially infest seed in the laboratory. For controlled environment assays, infested tomato seeds from the field and laboratory were placed othe n moistened blue blotter in square plastic boxes (10 cm x 10 cm) and incubated at 20/30 ˚C with an 8/16 hour light cycle, respectively. Infested tomato seeds from the field and laboratory were also planted in small plastic trays in soil (peat-lite medium) and placed in the greenhouse with 24/18 ˚C day and night temperatures, respectively, with a 14-hour photoperiod. Seed germination was assessed after eight days in the laboratory and 14 days in the greenhouse. Polymerase chain reaction (PCR) using the hrpB7 primers (RST65 [5’- GTCGTCGTTACGGCAAGGTGGTG-3’] and RST69 [5’-TCGCCCAGCGTCATCAGGCCATC-3’]) was performed to confirm presence or absence of the bacterial pathogen in seed lots collected from the field and in germinating seedlings in all experiments. For infested seed lots from the field, germination was lowest (84%) in the seed lot with the highest level of bacterial infestation (55%) and ranged from 84-98%. No adverse effect on germination was observed from artificially infested seeds for any bacterial concentration and method of infiltration when compared to a non-infested control. Germination in laboratory assays for artificially infested seeds ranged from 82-100%. In controlled environment assays, 2.5 % were PCR positive for the pathogen, and in the greenhouse assays, no infected seedlings were detected. From these experiments, X. euvesicatoria does not appear to adversely influence germination. The lowest rate of germination from field collected seed may be due to contamination with multiple pathogens and saprophytic organisms as no effect of artificial bacterial seed infestation in the laboratory on germination was observed. No evidence of systemic movement from seed to seedling was observed in the greenhouse assays; however, in the controlled environment assays, some seedlings were PCR positive. Additional experiments are underway with green fluorescent protein-expressing isolates to further characterize seed to seedling transmission of the bacterial leaf spot pathogen in tomato.Keywords: bacterial leaf spot, seed germination, tomato, Xanthomonas euvesicatoria
Procedia PDF Downloads 1347602 A Study of Sources and Control of Environmental Noise Pollution on Selected Areas of Osogbo, Capital of Osun State, Nigeria
Authors: Abdulrazaq Adepoju
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Climate change and its negative environmental challenges to humanity has for decades, taken the centre stage globally receiving attention on ways to take care of the menace and keep the damaging effects to manageable and tolerable level. However, noise pollution, another major environmental hazard militating against human habitation particularly in the developing countries of the world, is not receiving enough attention by the concerned authorities at all tiers of governance. A good knowledge of the major sources of environmental noise pollution will go a long way in assisting relevant stakeholders in planning, designing, and management of problems associated with noise pollution. This paper seeks to identify the major sources of noise in the built environment on selected areas of Osogbo, Nigeria. The paper adopted a survey research method of collecting data from surveys carried out on buildings around old Garage-Okefia axis, Old garage-Oja Oba axis, and Okefia-Olaiya junction axis, all within Osogbo metropolis using sound surveying metre. It was discovered that noise from vehicular and pedestrian traffic, commercial activities such as advertising vendors and religious buildings (churches and mosques) constitute major causes of noise in the study area. The paper recommends some measures to the affected stakeholders particularly government agencies on means of reducing noise pollution to a tolerable level in the study areas and places of the same industrial layout.Keywords: built environment, climate change, environmental pollution, noise
Procedia PDF Downloads 3617601 Studying the Impact of Architectural Styles on Student Satisfaction in University of Energy and Natural Resources, Sunyani
Authors: Frimpong Gyamfi Marious
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At the University of Energy and Natural Resources (UENR) in Sunyani, Ghana, this study investigates the connection between architectural styles and student satisfaction. The study investigates how various architectural components, such as building layout, lighting, ventilation, and aesthetics, affect students' comfort, educational experience, and general contentment with campus amenities. Data was gathered using a mixed-methods approach that included physical inspections of school facilities, in-depth interviews with students, working and none working staff. According to the results, modern designs that incorporate flexible learning areas, sufficient natural lighting, and appropriate ventilation greatly raise student satisfaction. Nonetheless, it was discovered that certain traditional architectural features included in campus structures enhanced students' feelings of cultural kinship. The study also identifies key architectural challenges affecting student comfort, including inadequate thermal control and limited social interaction spaces. Based on these findings, the research proposes design recommendations for future campus development that balance modern functionality with cultural sensitivity. This study contributes to the growing body of knowledge on educational architecture and provides practical insights for improving campus design to enhance student experience in tropical climates.Keywords: architecture, architectural styles, impact of architectural styles, impacts of architectural styles on students satisfaction
Procedia PDF Downloads 77600 Knowledge Elicitation Approach for Formal Ontology Design: An Exploratory Study Applied in Industry for Knowledge Management
Authors: Ouassila Labbani-Narsis, Christophe Nicolle
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Building formal ontologies remains a complex process for companies. In the literature, this process is based on the technical knowledge and expertise of domain experts, without further details on the used methodologies. Possible problems of disagreements between experts, expression of tacit knowledge related to high level know-how rarely verbalized, qualification of results by using cases, or simply adhesion of the group of experts, remain currently unsolved. This paper proposes a methodological approach based on knowledge elicitation for the conception of formal, consensual, and shared ontologies. The proposed approach is experimentally tested on industrial collaboration projects in the field of manufacturing (associating knowledge sources from multinational companies) and in the field of viticulture (associating explicit knowledge and implicit knowledge acquired through observation).Keywords: collaborative ontology engineering, knowledge elicitation, knowledge engineering, knowledge management
Procedia PDF Downloads 787599 Field Saturation Flow Measurement Using Dynamic Passenger Car Unit under Mixed Traffic Condition
Authors: Ramesh Chandra Majhi
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Saturation flow is a very important input variable for the design of signalized intersections. Saturation flow measurement is well established for homogeneous traffic. However, saturation flow measurement and modeling is a challenging task in heterogeneous characterized by multiple vehicle types and non-lane based movement. Present study focuses on proposing a field procedure for Saturation flow measurement and the effect of typical mixed traffic behavior at the signal as far as non-lane based traffic movement is concerned. Data collected during peak and off-peak hour from five intersections with varying approach width is used for validating the saturation flow model. The insights from the study can be used for modeling saturation flow and delay at signalized intersection in heterogeneous traffic conditions.Keywords: optimization, passenger car unit, saturation flow, signalized intersection
Procedia PDF Downloads 3277598 Oil Reservoirs Bifurcation Analysis in the Democratic Republic of Congo: Fractal Characterization Approach of Makelekese MS-25 Field
Authors: Leonard Mike McNelly Longwa, Divine Kusosa Musiku, Dieudonne Nahum Kabeya
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In this paper, the bifurcation analysis of oilfields in the Democratic Republic of Congo is presented in order to enhance petroleum production in an intense tectonic evolution characterized by distinct compressive and extensive phases and the digenetic transformation in the reservoirs during burial geological configuration. The use of porous media in the Makelekese MS-25 field has been established to simulate the boundaries within 3 sedimentary basins open to exploration including the coastal basin with an area of 5992 km², a central basin with an area of 800,000 km², the western branch of the East African Rift in which there are 50,000 km². The fractal characterization of complex hydro-dynamic fractures in oilfields is developed to facilitate the oil production process based on the reservoirs bifurcation model.Keywords: reservoir bifurcation, fractal characterization, permeability, conductivity, skin effect
Procedia PDF Downloads 1307597 Novel Synthesis of Metal Oxide Nanoparticles from Type IV Deep Eutectic Solvents
Authors: Lorenzo Gontrani, Marilena Carbone, Domenica Tommasa Donia, Elvira Maria Bauer, Pietro Tagliatesta
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One of the fields where DES shows remarkable added values is the synthesis Of inorganic materials, in particular nanoparticles. In this field, the higher- ent and highly-tunable nano-homogeneities of DES structure give origin to a marked templating effect, a precious role that has led to the recent bloom of a vast number of studies exploiting these new synthesis media to prepare Nanomaterials and composite structures of various kinds. In this contribution, the most recent developments in the field will be reviewed, and some ex-citing examples of novel metal oxide nanoparticles syntheses using non-toxic type-IV Deep Eutectic Solvents will be described. The prepared materials possess nanometric dimensions and show flower-like shapes. The use of the pre- pared nanoparticles as fluorescent materials for the detection of various contaminants is under development.Keywords: metal deep eutectic solvents, nanoparticles, inorganic synthesis, type IV DES, lamellar
Procedia PDF Downloads 1357596 Control of Base Isolated Benchmark using Combined Control Strategy with Fuzzy Algorithm Subjected to Near-Field Earthquakes
Authors: Hashem Shariatmadar, Mozhgansadat Momtazdargahi
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The purpose of control structure against earthquake is to dissipate earthquake input energy to the structure and reduce the plastic deformation of structural members. There are different methods for control structure against earthquake to reduce the structure response that they are active, semi-active, inactive and hybrid. In this paper two different combined control systems are used first system comprises base isolator and multi tuned mass dampers (BI & MTMD) and another combination is hybrid base isolator and multi tuned mass dampers (HBI & MTMD) for controlling an eight story isolated benchmark steel structure. Active control force of hybrid isolator is estimated by fuzzy logic algorithms. The influences of the combined systems on the responses of the benchmark structure under the two near-field earthquake (Newhall & Elcentro) are evaluated by nonlinear dynamic time history analysis. Applications of combined control systems consisting of passive or active systems installed in parallel to base-isolation bearings have the capability of reducing response quantities of base-isolated (relative and absolute displacement) structures significantly. Therefore in design and control of irregular isolated structures using the proposed control systems, structural demands (relative and absolute displacement and etc.) in each direction must be considered separately.Keywords: base-isolated benchmark structure, multi-tuned mass dampers, hybrid isolators, near-field earthquake, fuzzy algorithm
Procedia PDF Downloads 3047595 A Mathematical Study of Magnetic Field, Heat Transfer and Brownian Motion of Nanofluid over a Nonlinear Stretching Sheet
Authors: Madhu Aneja, Sapna Sharma
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Thermal conductivity of ordinary heat transfer fluids is not adequate to meet today’s cooling rate requirements. Nanoparticles have been shown to increase the thermal conductivity and convective heat transfer to the base fluids. One of the possible mechanisms for anomalous increase in the thermal conductivity of nanofluids is the Brownian motions of the nanoparticles in the basefluid. In this paper, the natural convection of incompressible nanofluid over a nonlinear stretching sheet in the presence of magnetic field is studied. The flow and heat transfer induced by stretching sheets is important in the study of extrusion processes and is a subject of considerable interest in the contemporary literature. Appropriate similarity variables are used to transform the governing nonlinear partial differential equations to a system of nonlinear ordinary (similarity) differential equations. For computational purpose, Finite Element Method is used. The effective thermal conductivity and viscosity of nanofluid are calculated by KKL (Koo – Klienstreuer – Li) correlation. In this model effect of Brownian motion on thermal conductivity is considered. The effect of important parameter i.e. nonlinear parameter, volume fraction, Hartmann number, heat source parameter is studied on velocity and temperature. Skin friction and heat transfer coefficients are also calculated for concerned parameters.Keywords: Brownian motion, convection, finite element method, magnetic field, nanofluid, stretching sheet
Procedia PDF Downloads 2187594 Fatigue Crack Behaviour in a Residual Stress Field at Fillet Welds in Ship Structures
Authors: Anurag Niranjan, Michael Fitzpatrick, Yin Jin Janin, Jazeel Chukkan, Niall Smyth
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Fillet welds are used in joining longitudinal stiffeners in ship structures. Welding residual stresses in fillet welds are generally distributed in a non-uniform manner, as shown in previous research the residual stress redistribution occurs under the cyclic loading that is experienced by such joints during service, and the combination of the initial residual stress, local constraints, and loading can alter the stress field in ways that are extremely difficult to predict. As the residual stress influences the crack propagation originating from the toe of the fillet welds, full understanding of the residual stress field and how it evolves is very important for structural integrity calculations. Knowledge of the residual stress redistribution in the presence of a flaw is therefore required for better fatigue life prediction. Moreover, defect assessment procedures such as BS7910 offer very limited guidance for flaw acceptance and the associated residual stress redistribution in the assessment of fillet welds. Therefore the objective of this work is to study a surface-breaking flaw at the weld toe region in a fillet weld under cyclic load, in conjunction with residual stress measurement at pre-defined crack depths. This work will provide details of residual stress redistribution under cyclic load in the presence of a crack. The outcome of this project will inform integrity assessment with respect to the treatment of residual stress in fillet welds. Knowledge of the residual stress evolution for this weld geometry will be greatly beneficial for flaw tolerance assessments (BS 7910, API 591).Keywords: fillet weld, fatigue, residual stress, structure integrity
Procedia PDF Downloads 1427593 Ghost Frequency Noise Reduction through Displacement Deviation Analysis
Authors: Paua Ketan, Bhagate Rajkumar, Adiga Ganesh, M. Kiran
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Low gear noise is an important sound quality feature in modern passenger cars. Annoying gear noise from the gearbox is influenced by the gear design, gearbox shaft layout, manufacturing deviations in the components, assembly errors and the mounting arrangement of the complete gearbox. Geometrical deviations in the form of profile and lead errors are often present on the flanks of the inspected gears. Ghost frequencies of a gear are very challenging to identify in standard gear measurement and analysis process due to small wavelengths involved. In this paper, gear whine noise occurring at non-integral multiples of gear mesh frequency of passenger car gearbox is investigated and the root cause is identified using the displacement deviation analysis (DDA) method. DDA method is applied to identify ghost frequency excitations on the flanks of gears arising out of generation grinding. Frequency identified through DDA correlated with the frequency of vibration and noise on the end-of-line machine as well as vehicle level measurements. With the application of DDA method along with standard lead profile measurement, gears with ghost frequency geometry deviations were identified on the production line to eliminate defective parts and thereby eliminate ghost frequency noise from a vehicle. Further, displacement deviation analysis can be used in conjunction with the manufacturing process simulation to arrive at suitable countermeasures for arresting the ghost frequency.Keywords: displacement deviation analysis, gear whine, ghost frequency, sound quality
Procedia PDF Downloads 1467592 The Impact of Socio – Cultural Factors on Female Entrepreneurial Intention: The Case of Algeria
Authors: Nesrine Bouguerra
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Entrepreneurship is seen as a necessary ingredient for stimulating economic growth and employment opportunities in all societies. SMEs account for a wide share of economic activity and development. they are the primary engine of job creation, income growth and poverty reduction. Indeed, government support for entrepreneurship is a strategic option to foster economic growth and females’ input in this regard, is of equal significance not only for employability and productivity but also to narrow the gender gap created by social attitudes and beliefs. This study investigates the impact of socio–cultural factors, among other barriers on female entrepreneurial intention in Algeria. Data will be collected using a mixed method approach (Questionnaires and Interviews) from women intending to become entrepreneurs and those already in the field. This study has conceptual, theoretical and empirical contributions to the field of entrepreneurship which will be unveiled throughout.Keywords: female entrepreneurship, SMEs, women, socio –cultural values, barriers
Procedia PDF Downloads 4527591 Optimization of Bifurcation Performance on Pneumatic Branched Networks in next Generation Soft Robots
Authors: Van-Thanh Ho, Hyoungsoon Lee, Jaiyoung Ryu
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Efficient pressure distribution within soft robotic systems, specifically to the pneumatic artificial muscle (PAM) regions, is essential to minimize energy consumption. This optimization involves adjusting reservoir pressure, pipe diameter, and branching network layout to reduce flow speed and pressure drop while enhancing flow efficiency. The outcome of this optimization is a lightweight power source and reduced mechanical impedance, enabling extended wear and movement. To achieve this, a branching network system was created by combining pipe components and intricate cross-sectional area variations, employing the principle of minimal work based on a complete virtual human exosuit. The results indicate that modifying the cross-sectional area of the branching network, gradually decreasing it, reduces velocity and enhances momentum compensation, preventing flow disturbances at separation regions. These optimized designs achieve uniform velocity distribution (uniformity index > 94%) prior to entering the connection pipe, with a pressure drop of less than 5%. The design must also consider the length-to-diameter ratio for fluid dynamic performance and production cost. This approach can be utilized to create a comprehensive PAM system, integrating well-designed tube networks and complex pneumatic models.Keywords: pneumatic artificial muscles, pipe networks, pressure drop, compressible turbulent flow, uniformity flow, murray's law
Procedia PDF Downloads 847590 Modelling of Lunar Lander’s Thruster’s Exhaust Plume Impingement in Vacuum
Authors: Mrigank Sahai, R. Sri Raghu
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This paper presents the modelling of rocket exhaust plume flow field and exhaust plume impingement in vacuum for the liquid apogee engine and attitude control thrusters of the lunar lander. Analytic formulations for rarefied gas kinetics has been taken as reference for modelling the plume flow field. The plume has been modelled as high speed, collision-less, axi-symmetric gas jet, expanding into vacuum and impinging at a normally set diffusive circular plate. Specular reflections have not been considered for the present study. Different parameters such as number density, temperature, pressure, flow velocity, heat flux etc., have been calculated and have been plotted against and compared to Direct Simulation Monte Carlo results. These analyses have provided important information for the placement of critical optical instruments and design of optimal thermal insulation for the hardware that may come in contact with the thruster exhaust.Keywords: collision-less gas, lunar lander, plume impingement, rarefied exhaust plume
Procedia PDF Downloads 2697589 Brand Creation for Community Product: A Case Study at Samut Songkram, Thailand
Authors: Cholpassorn Sitthiwarongchai
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The purposes of this paper were to search for the uniqueness of community products from Bang Khonthi District, Samut Songkram Province, Thailand and to create a proper brand for the community products. Four important questions were asked to identify the uniqueness of the community products. The first question: What is the brand of coconut sugar that community wants to imply? The answer was 100 percent authentic coconut sugar. The second question: What is the nature of this product? The answer was that it is a natural product without any harmful chemical. The third question is: Who are the target customers? The answer was that homemakers and tourists are target customers. The fourth question: What is the brand guarantee to customers? The answer was that the brand guarantees that the product is 100 percent natural process with a high quality and it is a community production. The findings revealed that in terms of product, customers rated quality and package as the two most important factors. In terms of price, customers rated lower price and a visible label as the two most important factors. In terms of place, customer rated layout and the cleanliness of the place as the two most important factors. In terms of promotion, customer rated public relations and brochure at the store as the most important factors. From the group discussion, the local community agreed that the brand for the community coconut sugar of Salapi community should be a picture of a green coconut tree and yellow color background. This brand implies the strength of community and authentic of the high quality natural product.Keywords: coconut sugar, community brand, Samut Songkram, natural product
Procedia PDF Downloads 3967588 Cultural Heritage Resources for Tourism, Two Countries – Two Approaches: A Comparative Analysis of Cultural Tourism Products in Turkey and Austria
Authors: Irfan Arikan, George Christian Steckenbauer
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Turkey and Austria are examples for highly developed tourism destinations, where tourism providers use cultural heritage and regional natural resources to develop modern tourism products in order to be successful on increasingly competitive international tourism markets. The use and exploitation of these resources follow on the one hand international standards of tourism marketing (as ‘sustainability’). Therefore, we find highly comparable internationalized products in these destinations (like hotel products, museums, spas etc.). On the other hand, development standards and processes strongly depend on local, regional and national cultures, which influence the way how people work, cooperate, think and create. Thus, cultural factors also influence the attitude towards cultural heritage and natural resources and the way, how these resources are used for the creation of tourism products. This leads to differences in the development of tourism products on several levels: 1. In the selection of cultural heritage and natural resources for the product development process 2. In the processes, how tourism products are created 3. In the way, how providers and marketing organisations work with tourism products based on cultural heritage or natural resources. Aim of this paper is to discover differences in these dimensions by analysing and comparing examples of tourism products in Turkey and Austria, both countries with a highly developed, high professional tourism industry and rich experience of stakeholders in tourism industry in the field of product development and marketing. The cases are selected from the following fields: + Cultural tourism / heritage tourism + City tourism + Industrial heritage tourism + Nature and outdoor tourism + Health tourism The cases are analysed based on available secondary data (as several cases are scientifically described) and expert interviews with local and regional stakeholders of tourism industry and tourism experts. The available primary and secondary data will be analysed and displayed in a comparative structure that allows to derive answers to the above stated research question. The result of the project therefore will be a more precise picture about the influence of cultural differences on the use and exploitation of resources in the field of tourism that allows developing recommendations for tourism industry, which must be taken into consideration to assure cultural and natural resources are treated in a sustainable and responsible way. The authors will edit these culture-cross recommendations in form of a ‘check-list’ that can be used as a ‘guideline’ for tourism professionals in the field of product development and marketing and therefore connects theoretical research to the field of practical application and closes the gap between academic research and the field of tourism practice.Keywords: cultural heritage, natural resources, Austria, Turkey
Procedia PDF Downloads 4927587 Evaluation of the Most Effective Insecticides against the Spodoptera Frugiperda, on the Maize Production
Authors: Ahmed Ali Hassan
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In 2016, the Fall Armyworm (FAW) was first discovered in Africa. FAW is abundantly present in Somalia and seriously harms the maize crop. This investigation examined the impact on maize productivity of three different pesticides used to combat the autumn armyworm, Spodoptera frugiperda (Noctuidae: Lepidoptera). During the 2020–2021 growing season, three insecticides (Malathion 57 EC, Ampligo150 ZC, and Carbryle 85 WP) were evaluated at field demonstration plots. Our result showed that, significant mortality of S. frugiperda was observed on the treatment plot treated with Amplico. Ampligo caused over 90% larval mortality after application. Malathion had moderate activity, causing 53.733% mortality after application, while Carbaryl was less effective, causing 36.367% mortality after application. Consequently, the current finding shows that the three selected insecticides reduced the damage and infestation level of S. frugiperda in the maize field conditions and the most effective treatment were Amplico.Keywords: pesticides, maize fall army worm, insecticides, mortality, S. frugiperda
Procedia PDF Downloads 707586 The Feasibility and Usability of Antennas Silence Zone for Localization and Path Finding
Authors: S. Malebary, W. Xu
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Antennas are important components that enable transmitting and receiving signals in mid-air (wireless). The radiation pattern of omni-directional (i.e., dipole) antennas, reflects the variation of power radiated by an antenna as a function of direction when transmitting. As the performance of the antenna is the same in transmitting and receiving, it also reflects the sensitivity of the antenna in different directions when receiving. The main observation when dealing with omni-directional antennas, regardless the application, is they equally radiate power in all directions in reference to Equivalent Isotropically Radiated Power (EIRP). Disseminating radio frequency signals in an omni-directional manner form a doughnut-shape-field with a cone in the middle of the elevation plane (when mounted vertically). In this paper, we investigate the existence of this physical phenomena namely silence cone zone (the zone where radiated power is nulled). First, we overview antenna types and properties that have the major impact on the shape of the electromagnetic field. Then we model various off the shelf dipoles in Matlab based on antennas’ features (dimensions, gain, operating frequency, … etc.) and compare the resulting radiation patterns. After that, we validate the existence of the null zone in Omni-directional antennas by conducting experiments and generating waveforms (using USRP1 and USRP2) at various frequencies using different types of antennas and gains in indoor/outdoor. We capture the generated waveforms around antennas' null zone in the reactive, near, and far field with a spectrum analyzer mounted on a drone, using various off the shelf antennas. We analyze the captured signals in RF-Explorer and plot the impact on received power and signal amplitude inside and around the null zone. Finally, it is concluded from evaluation and measurements the existence of null zones in Omni-directional antennas which we plan on extending this work in the near future to investigate the usability of the null zone for various applications such as localization and path finding.Keywords: antennas, amplitude, field regions, frequency, FSPL, omni-directional, radiation pattern, RSSI, silence zone cone
Procedia PDF Downloads 3037585 Use of Sentiel-2 Data to Monitor Plant Density and Establishment Rate of Winter Wheat Fields
Authors: Bing-Bing E. Goh
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Plant counting is a labour intensive and time-consuming task for the farmers. However, it is an important indicator for farmers to make decisions on subsequent field management. This study is to evaluate the potential of Sentinel-2 images using statistical analysis to retrieve information on plant density for monitoring, especially during critical period at the beginning of March. The model was calibrated with in-situ data from 19 winter wheat fields in Republic of Ireland during the crop growing season in 2019-2020. The model for plant density resulted in R2 = 0.77, RMSECV = 103 and NRMSE = 14%. This study has shown the potential of using Sentinel-2 to estimate plant density and quantify plant establishment to effectively monitor crop progress and to ensure proper field management.Keywords: winter wheat, remote sensing, crop monitoring, multivariate analysis
Procedia PDF Downloads 1617584 Compliance and Assessment Process of Information Technology in Accounting, in Turkey
Authors: Kocakaya Eda, Argun Doğan
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This study analyzed the present state of information technology in the field of accounting by bibliometric analysis of scientific studies on the impact on the transformation of e-billing and tax managementin Turkey. With comparative bibliometric analysis, the innovation and positive effects of the process that changed with e-transformation in the field of accounting with e-transformation in businesses and the information technologies used in accounting and tax management were analyzed comparatively. By evaluating the data obtained as a result of these analyzes, suggestions on the use of information technologies in accounting and tax management and the positive and negative effects of e-transformation on the analyzed activities of the enterprises were emphasized. With the e-transformation, which will be realized with the most efficient use of information technologies in Turkey. The synergy and efficiency of IT technology developments in avcoounting and finance should be revealed in the light of scientific data, from the smallest business to the largest economic enterprises.Keywords: information technologies, E-invoice, E-Tax management, E-transformation, accounting programs
Procedia PDF Downloads 1197583 2D PbS Nanosheets Synthesis and Their Applications as Field Effect Transistors or Solar Cells
Authors: T. Bielewicz, S. Dogan, C. Klinke
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Two-dimensional, solution-processable semiconductor materials are interesting for low-cost electronic applications [1]. We demonstrate the synthesis of lead sulfide nanosheets and how their size, shape and height can be tuned by varying concentrations of pre-cursors, ligands and by varying the reaction temperature. Especially, the charge carrier confinement in the nanosheets’ height adjustable from 2 to 20 nm has a decisive impact on their electronic properties. This is demonstrated by their use as conduction channel in a field effect transistor [2]. Recently we also showed that especially thin nanosheets show a high carrier multiplication (CM) efficiency [3] which could make them, through the confinement induced band gap and high photoconductivity, very attractive for application in photovoltaic devices. We are already able to manufacture photovoltaic devices out of single nanosheets which show promising results.Keywords: physical sciences, chemistry, materials, chemistry, colloids, physics, condensed-matter physics, semiconductors, two-dimensional materials
Procedia PDF Downloads 3017582 Potential of Sunflower (Helianthus annuus L.) for Phytoremediation of Soils Contaminated with Heavy Metals
Authors: Violina R. Angelova, Mariana N. Perifanova-Nemska, Galina P. Uzunova, Krasimir I. Ivanov, Huu Q. Lee
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A field study was conducted to evaluate the efficacy of the sunflower (Helianthus annuus L.) for phytoremediation of contaminated soils. The experiment was performed on an agricultural field contaminated by the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Field experiments with a randomized, complete block design with five treatments (control, compost amendments added at 20 and 40 t/daa, and vemicompost amendments added at 20 and 40 t/daa) were carried out. The accumulation of heavy metals in the sunflower plant and the quality of the sunflower oil (heavy metals and fatty acid composition) were determined. The tested organic amendments significantly influenced the uptake of Pb, Zn and Cd by the sunflower plant. The incorporation of 40 t/decare of compost and 20 t/decare of vermicompost to the soil led to an increase in the ability of the sunflower to take up and accumulate Cd, Pb and Zn. Sunflower can be subjected to the accumulators of Pb, Zn and Cd and can be successfully used for phytoremediation of contaminated soils with heavy metals. The 40 t/daa compost treatment led to a decrease in heavy metal content in sunflower oil to below the regulated limits. Oil content and fatty acids composition were affected by compost and vermicompost amendment treatments. Adding compost and vermicompost increased the oil content in the seeds. Adding organic amendments increased the content of stearic, palmitoleic and oleic acids, and reduced the content of palmitic and gadoleic acids in sunflower oil. The possibility of further industrial processing of seeds to oil and use of the obtained oil will make sunflowers economically interesting crops for farmers of phytoremediation technology.Keywords: heavy metals, phytoremediation, polluted soils, sunflower
Procedia PDF Downloads 2337581 Familiarity with Nursing and Description of Nurses Duties
Authors: Narges Solaymani
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Definition of Nurse: Nurse: A person who is educated and skilled in the field of scientific principles and professional skills of health care, treatment, and medical training of patients. Nursing is a very important profession in the societies of the world. Although in the past, all caregivers of the sick and disabled were called nurses, nowadays, a nurse is a person who has a university education in this field. There are nurses in bachelor's, master's, and doctoral degrees in nursing. New courses have been launched in the master's degree based on duty-oriented nurses. A nurse cannot have an independent treatment center but is a member of the treatment team in established treatment centers such as hospitals, clinics, or offices. Nurses can establish counseling centers and provide nursing services at home. According to the standards, the number of nurses should be three times the number of doctors or twice the number of hospital beds, or there should be three nurses for every thousand people. Also, international standards show that in the internal and surgical department, every 4 to 6 patients should have a nurse.Keywords: nurse, intensive care, CPR, bandage
Procedia PDF Downloads 687580 Monitorization of Junction Temperature Using a Thermal-Test-Device
Authors: B. Arzhanov, A. Correia, P. Delgado, J. Meireles
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Due to the higher power loss levels in electronic components, the thermal design of PCBs (Printed Circuit Boards) of an assembled device becomes one of the most important quality factors in electronics. Nonetheless, some of leading causes of the microelectronic component failures are due to higher temperatures, the leakages or thermal-mechanical stress, which is a concern, is the reliability of microelectronic packages. This article presents an experimental approach to measure the junction temperature of exposed pad packages. The implemented solution is in a prototype phase, using a temperature-sensitive parameter (TSP) to measure temperature directly on the die, validating the numeric results provided by the Mechanical APDL (Ansys Parametric Design Language) under same conditions. The physical device-under-test is composed by a Thermal Test Chip (TTC-1002) and assembly in a QFN cavity, soldered to a test-board according to JEDEC Standards. Monitoring the voltage drop across a forward-biased diode, is an indirectly method but accurate to obtain the junction temperature of QFN component with an applied power range between 0,3W to 1.5W. The temperature distributions on the PCB test-board and QFN cavity surface were monitored by an infra-red thermal camera (Goby-384) controlled and images processed by the Xeneth software. The article provides a set-up to monitorize in real-time the junction temperature of ICs, namely devices with the exposed pad package (i.e. QFN). Presenting the PCB layout parameters that the designer should use to improve thermal performance, and evaluate the impact of voids in solder interface in the device junction temperature.Keywords: quad flat no-Lead packages, exposed pads, junction temperature, thermal management and measurements
Procedia PDF Downloads 2867579 Experimental Simulation of Soil Boundary Condition for Dynamic Studies
Authors: Omar S. Qaftan, T. T. Sabbagh
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This paper studies the free-field response by adopting a flexible membrane container as soil boundary for experimental shaking table tests. The influence of the soil container boundary on the soil behaviour and the dynamic soil properties under seismic effect were examined. A flexible container with 1/50 scale factor was adopted in the experimental tests, including construction, instrumentation, and determination of the results of dynamic tests on a shaking table. Horizontal face displacements and accelerations were analysed to determine the influence of the container boundary on the performance of the soil. The outputs results show that the flexible boundary container allows more displacement and larger accelerations. The soil in a rigid wall container cannot deform as similar as the soil in the real field does. Therefore, the response of flexible container tested is believed to be more reliable for soil boundary than that in the rigid container.Keywords: soil, seismic, earthquake, interaction
Procedia PDF Downloads 2987578 Field-Free Orbital Hall Current-Induced Deterministic Switching in the MO/Co₇₁Gd₂₉/Ru Structure
Authors: Zelalem Abebe Bekele, Kun Lei, Xiukai Lan, Xiangyu Liu, Hui Wen, Kaiyou Wang
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Spin-polarized currents offer an efficient means of manipulating the magnetization of a ferromagnetic layer for big data and neuromorphic computing. Research has shown that the orbital Hall effect (OHE) can produce orbital currents, potentially surpassing the counter spin currents induced by the spin Hall effect. However, it’s essential to note that orbital currents alone cannot exert torque directly on a ferromagnetic layer, necessitating a conversion process from orbital to spin currents. Here, we present an efficient method for achieving perpendicularly magnetized spin-orbit torque (SOT) switching by harnessing the localized orbital Hall current generated from a Mo layer within a Mo/CoGd device. Our investigation reveals a remarkable enhancement in the interface-induced planar Hall effect (PHE) within the Mo/CoGd bilayer, resulting in the generation of a z-polarized planar current for manipulating the magnetization of CoGd layer without the need for an in-plane magnetic field. Furthermore, the Mo layer induces out-of-plane orbital current, boosting the in-plane and out-of-plane spin polarization by converting the orbital current into spin current within the dual-property CoGd layer. At the optimal Mo layer thickness, a low critical magnetization switching current density of 2.51×10⁶ A cm⁻² is achieved. This breakthrough opens avenues for all-electrical control energy-efficient magnetization switching through orbital current, advancing the field of spin-orbitronics.Keywords: spin-orbit torque, orbital hall effect, spin hall current, orbital hall current, interface-generated planar hall current, anisotropic magnetoresistance
Procedia PDF Downloads 55