Search results for: low velocity impact
11021 Measurement and Prediction of Speed of Sound in Petroleum Fluids
Authors: S. Ghafoori, A. Al-Harbi, B. Al-Ajmi, A. Al-Shaalan, A. Al-Ajmi, M. Ali Juma
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Seismic methods play an important role in the exploration for hydrocarbon reservoirs. However, the success of the method depends strongly on the reliability of the measured or predicted information regarding the velocity of sound in the media. Speed of sound has been used to study the thermodynamic properties of fluids. In this study, experimental data are reported and analyzed on the speed of sound in toluene and octane binary mixture. Three-factor three-level Box-Benhkam design is used to determine the significance of each factor, the synergetic effects of the factors, and the most significant factors on speed of sound. The developed mathematical model and statistical analysis provided a critical analysis of the simultaneous interactive effects of the independent variables indicating that the developed quadratic models were highly accurate and predictive.Keywords: experimental design, octane, speed of sound, toluene
Procedia PDF Downloads 27611020 Stable Time Reversed Integration of the Navier-Stokes Equation Using an Adjoint Gradient Method
Authors: Jurriaan Gillissen
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This work is concerned with stabilizing the numerical integration of the Navier-Stokes equation (NSE), backwards in time. Applications involve the detection of sources of, e.g., sound, heat, and pollutants. Stable reverse numerical integration of parabolic differential equations is also relevant for image de-blurring. While the literature addresses the reverse integration problem of the advection-diffusion equation, the problem of numerical reverse integration of the NSE has, to our knowledge, not yet been addressed. Owing to the presence of viscosity, the NSE is irreversible, i.e., when going backwards in time, the fluid behaves, as if it had a negative viscosity. As an effect, perturbations from the perfect solution, due to round off errors or discretization errors, grow exponentially in time, and reverse integration of the NSE is inherently unstable, regardless of using an implicit time integration scheme. Consequently, some sort of filtering is required, in order to achieve a stable, numerical, reversed integration. The challenge is to find a filter with a minimal adverse affect on the accuracy of the reversed integration. In the present work, we explore an adjoint gradient method (AGM) to achieve this goal, and we apply this technique to two-dimensional (2D), decaying turbulence. The AGM solves for the initial velocity field u0 at t = 0, that, when integrated forward in time, produces a final velocity field u1 at t = 1, that is as close as is feasibly possible to some specified target field v1. The initial field u0 defines a minimum of a cost-functional J, that measures the distance between u1 and v1. In the minimization procedure, the u0 is updated iteratively along the gradient of J w.r.t. u0, where the gradient is obtained by transporting J backwards in time from t = 1 to t = 0, using the adjoint NSE. The AGM thus effectively replaces the backward integration by multiple forward and backward adjoint integrations. Since the viscosity is negative in the adjoint NSE, each step of the AGM is numerically stable. Nevertheless, when applied to turbulence, the AGM develops instabilities, which limit the backward integration to small times. This is due to the exponential divergence of phase space trajectories in turbulent flow, which produces a multitude of local minima in J, when the integration time is large. As an effect, the AGM may select unphysical, noisy initial conditions. In order to improve this situation, we propose two remedies. First, we replace the integration by a sequence of smaller integrations, i.e., we divide the integration time into segments, where in each segment the target field v1 is taken as the initial field u0 from the previous segment. Second, we add an additional term (regularizer) to J, which is proportional to a high-order Laplacian of u0, and which dampens the gradients of u0. We show that suitable values for the segment size and for the regularizer, allow a stable reverse integration of 2D decaying turbulence, with accurate results for more then O(10) turbulent, integral time scales.Keywords: time reversed integration, parabolic differential equations, adjoint gradient method, two dimensional turbulence
Procedia PDF Downloads 22411019 The Impact of Using Authentic Materials on Students' Motivation in Learning Indonesian Language as a Foreign Language
Authors: Ratna Elizabeth
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Motivation is a very important factor since it contributes a lot to the students’ success in learning a language. Using authentic materials is believed as a mean of increasing the motivation. The materials define as authentic if they are not specifically written for the purpose of language teaching. They are genuine spoken or written language data which are drawn from many different sources. The intention of this study is to investigate the impact of using of authentic materials on students’ motivation. A single case study is conducted to the grade 9 students who learn Indonesian Language as a Foreign Language (ILFL) at an international school in Jakarta, Indonesia. Questionnaires are also distributed to the students to know their perceptions on the using of authentic materials. The results show that the using of authentic materials has increased the students’ motivation in learning the language.Keywords: authentic materials, ILFL, language learning, motivation
Procedia PDF Downloads 38811018 The Effect of Surface Modifiers on the Mechanical and Morphological Properties of Waste Silicon Carbide Filled High-Density Polyethylene
Authors: R. Dangtungee, A. Rattanapan, S. Siengchin
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Waste silicon carbide (waste SiC) filled high-density polyethylene (HDPE) with and without surface modifiers were studied. Two types of surface modifiers namely; high-density polyethylene-grafted-maleic anhydride (HDPE-g-MA) and 3-aminopropyltriethoxysilane have been used in this study. The composites were produced using a two roll mill, extruder and shaped in a hydraulic compression molding machine. The mechanical properties of polymer composites such as flexural strength and modulus, impact strength, tensile strength, stiffness and hardness were investigated over a range of compositions. It was found that, flexural strength and modulus, tensile modulus and hardness increased, whereas impact strength and tensile strength decreased with the increasing in filler contents, compared to the neat HDPE. At similar filler content, the effect of both surface modifiers increased flexural modulus, impact strength, tensile strength and stiffness but reduced the flexural strength. Morphological investigation using SEM revealed that the improvement in mechanical properties was due to enhancement of the interfacial adhesion between waste SiC and HDPE.Keywords: high-density polyethylene, HDPE-g-MA, mechanical properties, morphological properties, silicon carbide, waste silicon carbide
Procedia PDF Downloads 36311017 A Study on the Impact of Covid-19 on Primary Healthcare Workers in Ekiti State, South-West Nigeria
Authors: Adeyinka Adeniran, Omowunmi Bakare, Esther Oluwole, Florence Chieme, Temitope Durojaiye, Modupe Akinyinka, Omobola Ojo, Babatunde Olujobi, Marcus Ilesanmi, Akintunde Ogunsakin
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Introduction: Globally, COVID-19 has greatly impacted the human race physically, socially, mentally, and economically. However, healthcare workers seemed to bear the greatest impact. The study, therefore, sought to assess the impact of COVID-19 on the primary healthcare workers in Ekiti, South-west Nigeria. Methods: The study was a cross-sectional descriptive study using a quantitative data collection method of 716 primary healthcare workers in Ekiti state. Respondents were selected using an online convenience sampling method via their social media platforms. Data was collected, collated, and analyzed using SPSS version 25 software and presented as frequency tables, mean and standard deviation. Bivariate and multivariate analyses were conducted using a t-test, and the level of statistical significance was set at p<0.05. Results: Less than half (47.1%) of respondents were between 41-50 age group and a mean age of 44.4+6.4SD. A majority (89.4%) were female, and almost all (96.2%) were married. More than (90%) had ever heard of Coronavirus, and (85.8%) had to spend more money on activities of daily living such as transportation (90.1%), groceries (80.6%), assisting relations (95.8%) and sanitary measures (disinfection) at home (95.0%). COVID-19 had a huge negative impact on about (89.7%) of healthcare workers, with a mean score of 22+4.8. Conclusion: COVID-19 negatively impacted the daily living and professional duties of primary healthcare workers, which reflected their psychological, physical, social, and economic well-being. Disease outbreaks are unlikely to disappear in the near future. Hence, global proactive interventions and homegrown measures should be adopted to protect healthcare workers and save lives.Keywords: Covid-19, health workforce, primary health care, health systems, depression
Procedia PDF Downloads 8411016 Repair of Thermoplastic Composites for Structural Applications
Authors: Philippe Castaing, Thomas Jollivet
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As a result of their advantages, i.e. recyclability, weld-ability, environmental compatibility, long (continuous) fiber thermoplastic composites (LFTPC) are increasingly used in many industrial sectors (mainly automotive and aeronautic) for structural applications. Indeed, in the next ten years, the environmental rules will put the pressure on the use of new structural materials like composites. In aerospace, more than 50% of the damage are due to stress impact and 85% of damage are repaired on the fuselage (fuselage skin panels and around doors). With the arrival of airplanes mainly of composite materials, replacement of sections or panels seems difficult economically speaking and repair becomes essential. The objective of the present study is to propose a solution of repair to prevent the replacement the damaged part in thermoplastic composites in order to recover the initial mechanical properties. The classification of impact damage is not so not easy : talking about low energy impact (less than 35 J) can be totally wrong when high speed or weak thicknesses as well as thermoplastic resins are considered. Crash and perforation with higher energy create important damages and the structures are replaced without repairing, so we just consider here damages due to impacts at low energy that are as follows for laminates : − Transverse cracking; − Delamination; − Fiber rupture. At low energy, the damages are barely visible but can nevertheless reduce significantly the mechanical strength of the part due to resin cracks while few fiber rupture is observed. The patch repair solution remains the standard one but may lead to the rupture of fibers and consequently creates more damages. That is the reason why we investigate the repair of thermoplastic composites impacted at low energy. Indeed, thermoplastic resins are interesting as they absorb impact energy through plastic strain. The methodology is as follows: - impact tests at low energy on thermoplastic composites; - identification of the damage by micrographic observations; - evaluation of the harmfulness of the damage; - repair by reconsolidation according to the extent of the damage ; -validation of the repair by mechanical characterization (compression). In this study, the impacts tests are performed at various levels of energy on thermoplastic composites (PA/C, PEEK/C and PPS/C woven 50/50 and unidirectional) to determine the level of impact energy creating damages in the resin without fiber rupture. We identify the extent of the damage by US inspection and micrographic observations in the plane part thickness. The samples were in addition characterized in compression to evaluate the loss of mechanical properties. Then the strategy of repair consists in reconsolidating the damaged parts by thermoforming, and after reconsolidation the laminates are characterized in compression for validation. To conclude, the study demonstrates the feasibility of the repair for low energy impact on thermoplastic composites as the samples recover their properties. At a first step of the study, the “repair” is made by reconsolidation on a thermoforming press but we could imagine a process in situ to reconsolidate the damaged parts.Keywords: aerospace, automotive, composites, compression, damages, repair, structural applications, thermoplastic
Procedia PDF Downloads 30411015 Impact of Charging PHEV at Different Penetration Levels on Power System Network
Authors: M. R. Ahmad, I. Musirin, M. M. Othman, N. A. Rahmat
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Plug-in Hybrid-Electric Vehicle (PHEV) has gained immense popularity in recent years. PHEV offers numerous advantages compared to the conventional internal-combustion engine (ICE) vehicle. Millions of PHEVs are estimated to be on the road in the USA by 2020. Uncoordinated PHEV charging is believed to cause severe impacts to the power grid; i.e. feeders, lines and transformers overload and voltage drop. Nevertheless, improper PHEV data model used in such studies may cause the findings of their works is in appropriated. Although smart charging is more attractive to researchers in recent years, its implementation is not yet attainable on the street due to its requirement for physical infrastructure readiness and technology advancement. As the first step, it is finest to study the impact of charging PHEV based on real vehicle travel data from National Household Travel Survey (NHTS) and at present charging rate. Due to the lack of charging station on the street at the moment, charging PHEV at home is the best option and has been considered in this work. This paper proposed a technique that comprehensively presents the impact of charging PHEV on power system networks considering huge numbers of PHEV samples with its traveling data pattern. Vehicles Charging Load Profile (VCLP) is developed and implemented in IEEE 30-bus test system that represents a portion of American Electric Power System (Midwestern US). Normalization technique is used to correspond to real time loads at all buses. Results from the study indicated that charging PHEV using opportunity charging will have significant impacts on power system networks, especially whereas bigger battery capacity (kWh) is used as well as for higher penetration level.Keywords: plug-in hybrid electric vehicle, transportation electrification, impact of charging PHEV, electricity demand profile, load profile
Procedia PDF Downloads 28711014 Experimental and Numerical Investigation of Flow Control Using a Novel Active Slat
Authors: Basman Elhadidi, Islam Elqatary, Osama Saaid, Hesham Othman
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An active slat is developed to increase the lift and delay the separation for a DU96-W180 airfoil. The active slat is a fixed slat that can be closed, fully opened or intermittently opened by a rotating vane depending on the need. Experimental results show that the active slat has reduced the mean pressure and increased the mean velocity on the suction side of the airfoil for all positive angles of attack, indicating an increase of lift. The experimental data and numerical simulations also show that the direction of actuator vane rotation can influence the mixing of the flow streams on the suction side and hence influence the aerodynamic performance.Keywords: active slat, flow control, experimental investigation, aerodynamic performance
Procedia PDF Downloads 43711013 Some Aspects of Social Media Marketing (Georgian Case)
Authors: Nugzar Todua, Charita Jashi
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This paper is focusing on the attitude of Georgian consumers toward social media, influence of social media on consumer buying behavior. The purpose of this paper is to explore the impact and usage of social media marketing strategies for Georgian companies and consumers in the new reality of Georgia. There is a lack of research on social media marketing in Georgia, especially the topic which analyzes the possible purchase influence of consumers. The result of marketing research has revealed that social webs are mostly used by Georgian consumers, but they have little impact on the buying decision. The research method was exploratory in nature in the sense that there is no previous academic research about consumers’ attitude towards social media marketing.Keywords: marketing research, purchasing behavior, social media marketing, social networking sites
Procedia PDF Downloads 51611012 Overall Function and Symptom Impact of Self-Applied Myofascial Release in Adult Patients With Fibromyalgia. A Seven-Week Pilot Study
Authors: Domenica Tambasco, Riina Bray, Sophia Jaworski, Gillian Grant, Celeste Corkery
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Fibromyalgia is a chronic condition characterized by widespread musculoskeletal pain, fatigue, and reduced function. Management of symptoms include medications, physical treatments and mindfulness therapies. Myofascial Release is a modality that has been successfully applied in var-ious musculoskeletal conditions. However, to the author’s best knowledge, it is not yet recog-nized as a self-management therapy option in Fibromyalgia. In this study, we investigated whether Self-applied Myofascial Release (SMR) is associated with overall improved function and symptoms in Fibromyalgia. Methods: Eligible adult patients with a confirmed diagnosis of Fibromyalgia at Women’s College Hospital were recruited to SMR. Sessions ran for 1 hour once a week for 7 weeks, led by the same two Physiotherapists knowledgeable in this physical treat-ment modality. The main outcome measure was an overall impact score for function and symp-toms based on the validated assessment tool for Fibromyalgia, the Revised Fibromyalgia Impact Questionnaire (FIQR), measured pre and post-intervention. Both descriptive and analytical methods were applied and reported. Results: We analyzed results using a paired t-test to deter-mine if there was a statistically significant difference in mean FIQR scores between initial (pre-intervention) and final (post-intervention) scores. A clinically significant difference in FIQR was defined as a reduction in score by 10 or more points. Conclusions: Our pilot study showed that SMR appeared to be a safe and effective intervention for our Fibromyalgia participants and the overall impact on function and symptoms occurred in only 7 weeks. Further studies with larger sample sizes comparing SMR to other physical treatment modalities (such as stretching) in an RCT are recommended.Keywords: fibromyalgia, myofascial release, physical therapy, FIQR
Procedia PDF Downloads 7611011 The Learning Impact of a 4-Dimensional Digital Construction Learning Environment
Authors: Chris Landorf, Stephen Ward
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This paper addresses a virtual environment approach to work integrated learning for students in construction-related disciplines. The virtual approach provides a safe and pedagogically rigorous environment where students can apply theoretical knowledge in a simulated real-world context. The paper describes the development of a 4-dimensional digital construction environment and associated learning activities funded by the Australian Office for Learning and Teaching. The environment was trialled with over 1,300 students and evaluated through questionnaires, observational studies and coursework analysis. Results demonstrate a positive impact on students’ technical learning and collaboration skills, but there is need for further research in relation to critical thinking skills and work-readiness.Keywords: architectural education, construction industry, digital learning environments, immersive learning
Procedia PDF Downloads 41111010 Adaptive Cooperative Control of Nonholonomic Mobile Robot Based on Immersion and Invariance
Authors: Imil Hamda Imran, Sami El Ferik
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This paper deals with adaptive cooperative control of non holonomic mobile robot moved together in a given formation. The controller is designed based on the Immersion and Invariance (I&I) approach. I&I is a framework for adaptive stabilization of nonlinear systems with uncertain parameters. We investigate the tracking control of non holonomic mobile robot with uncertainties in The I&I-based adaptive controller regulates the angular and linear velocity of non holonomic mobile robot. The results demonstrate that the ability of I&I-based adaptive cooperative control in tracking the position of non holonomic mobile robot.Keywords: nonholonomic mobile robot, immersion and invariance, adaptive control, uncertain nonlinear systems
Procedia PDF Downloads 49911009 The Status of Precision Agricultural Technology Adoption on Row Crop Farms vs. Specialty Crop Farms
Authors: Shirin Ghatrehsamani
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Higher efficiency and lower environmental impact are the consequence of using advanced technology in farming. They also help to decrease yield variability by diminishing weather variability impact, optimizing nutrient and pest management as well as reducing competition from weeds. A better understanding of the pros and cons of applying technology and finding the main reason for preventing the utilization of the technology has a significant impact on developing technology adoption among farmers and producers in the digital agriculture era. The results from two surveys carried out in 2019 and 2021 were used to investigate whether the crop types had an impact on the willingness to utilize technology on the farms. The main focus of the questionnaire was on utilizing precision agriculture (PA) technologies among farmers in some parts of the united states. Collected data was analyzed to determine the practical application of various technologies. The survey results showed more similarities in the main reason not to use PA between the two crop types, but the present application of using technology in specialty crops is generally five times larger than in row crops. GPS receiver applications were reported similar for both types of crops. Lack of knowledge and high cost of data handling were cited as the main problems. The most significant difference was among using variable rate technology, which was 43% for specialty crops while was reported 0% for row crops. Pest scouting and mapping were commonly used for specialty crops, while they were rarely applied for row crops. Survey respondents found yield mapping, soil sampling map, and irrigation scheduling were more valuable for specialty crops than row crops in management decisions. About 50% of the respondents would like to share the PA data in both types of crops. Almost 50 % of respondents got their PA information from retailers in both categories, and as the second source, using extension agents were more common in specialty crops than row crops.Keywords: precision agriculture, smart farming, digital agriculture, technology adoption
Procedia PDF Downloads 11411008 Exploring the Contribution of Dynamic Capabilities to a Firm's Value Creation: The Role of Competitive Strategy
Authors: Mona Rashidirad, Hamid Salimian
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Dynamic capabilities, as the most considerable capabilities of firms in the current fast-moving economy may not be sufficient for performance improvement, but their contribution to performance is undeniable. While much of the extant literature investigates the impact of dynamic capabilities on organisational performance, little attention has been devoted to understand whether and how dynamic capabilities create value. Dynamic capabilities as the mirror of competitive strategies should enable firms to search and seize new ideas, integrate and coordinate the firm’s resources and capabilities in order to create value. A careful investigation to the existing knowledge base remains us puzzled regarding the relationship among competitive strategies, dynamic capabilities and value creation. This study thus attempts to fill in this gap by empirically investigating the impact of dynamic capabilities on value creation and the mediating impact of competitive strategy on this relationship. We aim to contribute to dynamic capability view (DCV), in both theoretical and empirical senses, by exploring the impact of dynamic capabilities on firms’ value creation and whether competitive strategy can play any role in strengthening/weakening this relationship. Using a sample of 491 firms in the UK telecommunications market, the results demonstrate that dynamic sensing, learning, integrating and coordinating capabilities play a significant role in firm’s value creation, and competitive strategy mediates the impact of dynamic capabilities on value creation. Adopting DCV, this study investigates whether the value generating from dynamic capabilities depends on firms’ competitive strategy. This study argues a firm’s competitive strategy can mediate its ability to derive value from its dynamic capabilities and it explains the extent a firm’s competitive strategy may influence its value generation. The results of the dynamic capabilities-value relationships support our expectations and justify the non-financial value added of the four dynamic capability processes in a highly turbulent market, such as UK telecommunications. Our analytical findings of the relationship among dynamic capabilities, competitive strategy and value creation provide further evidence of the undeniable role of competitive strategy in deriving value from dynamic capabilities. The results reinforce the argument for the need to consider the mediating impact of organisational contextual factors, such as firm’s competitive strategy to examine how they interact with dynamic capabilities to deliver value. The findings of this study provide significant contributions to theory. Unlike some previous studies which conceptualise dynamic capabilities as a unidimensional construct, this study demonstrates the benefits of understanding the details of the link among the four types of dynamic capabilities, competitive strategy and value creation. In terms of contributions to managerial practices, this research draws attention to the importance of competitive strategy in conjunction with development and deployment of dynamic capabilities to create value. Managers are now equipped with solid empirical evidence which explains why DCV has become essential to firms in today’s business world.Keywords: dynamic capabilities, resource based theory, value creation, competitive strategy
Procedia PDF Downloads 24111007 The Effects of Quality of Web-Based Applications on Competitive Advantage: An Empirical Study in Commercial Banks in Jordan
Authors: Faisal Asad Aburub
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Many organizations are investing in web applications and technologies in order to be competitive, some of them could not achieve its goals. The quality of web-based applications could play an important role for organizations to be competitive. So the aim of this study is to investigate the impact of quality of web-based applications to achieve a competitive advantage. A new model has been developed. An empirical investigation was performed on a banking sector in Jordan to test the new model. The results show that impact of web-based applications on competitive advantage is significant. Finally, further work is planned to validate and evaluate the proposed model using several domains.Keywords: competitive advantage, web-based applications, empirical investigation, commercial banks in Jordan
Procedia PDF Downloads 34111006 Finding the Free Stream Velocity Using Flow Generated Sound
Authors: Saeed Hosseini, Ali Reza Tahavvor
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Sound processing is one the subjects that newly attracts a lot of researchers. It is efficient and usually less expensive than other methods. In this paper the flow generated sound is used to estimate the flow speed of free flows. Many sound samples are gathered. After analyzing the data, a parameter named wave power is chosen. For all samples, the wave power is calculated and averaged for each flow speed. A curve is fitted to the averaged data and a correlation between the wave power and flow speed is founded. Test data are used to validate the method and errors for all test data were under 10 percent. The speed of the flow can be estimated by calculating the wave power of the flow generated sound and using the proposed correlation.Keywords: the flow generated sound, free stream, sound processing, speed, wave power
Procedia PDF Downloads 41511005 Transformative Measures in Chemical and Petrochemical Industry Through Agile Principles and Industry 4.0 Technologies
Authors: Bahman Ghorashi
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The immense awareness of the global climate change has compelled traditional fossil fuel companies to develop strategies to reduce their carbon footprint and simultaneously consider the production of various sources of clean energy in order to mitigate the environmental impact of their operations. Similarly, supply chain issues, the scarcity of certain raw materials, energy costs as well as market needs, and changing consumer expectations have forced the traditional chemical industry to reexamine their time-honored modes of operation. This study examines how such transformative change might occur through the applications of agile principles as well as industry 4.0 technologies. Clearly, such a transformation is complex, costly, and requires a total commitment on the part of the top leadership and the entire management structure. Factors that need to be considered include organizational speed of change, a restructuring that would lend itself toward collaboration and the selling of solutions to customers’ problems, rather than just products, integrating ‘along’ as well as ‘across’ value chains, mastering change and uncertainty as well as a recognition of the importance of concept-to-cash time, i.e., the velocity of introducing new products to market, and the leveraging of people and information. At the same time, parallel to implementing such major shifts in the ethos, and the fabric of the organization, the change leaders should remain mindful of the companies’ DNA while incorporating the necessary DNA defying shifts. Furthermore, such strategic maneuvers should inevitably incorporate the managing of the upstream and downstream operations, harnessing future opportunities, preparing and training the workforce, implementing faster decision making and quick adaptation to change, managing accelerated response times, as well as forming autonomous and cross-functional teams. Moreover, the leaders should establish the balance between high-value solutions versus high-margin products, fully implement digitization of operations and, when appropriate, incorporate the latest relevant technologies, such as: AI, IIoT, ML, and immersive technologies. This study presents a summary of the agile principles and the relevant technologies and draws lessons from some of the best practices that are already implemented within the chemical industry in order to establish a roadmap to agility. Finally, the critical role of educational institutions in preparing the future workforce for Industry 4.0 is addressed.Keywords: agile principles, immersive technologies, industry 4.0, workforce preparation
Procedia PDF Downloads 10611004 A Prediction Model of Tornado and Its Impact on Architecture Design
Authors: Jialin Wu, Zhiwei Lian, Jieyu Tang, Jingyun Shen
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Tornado is a serious and unpredictable natural disaster, which has an important impact on people's production and life. The probability of being hit by tornadoes in China was analyzed considering the principles of tornado formation. Then some suggestions on layout and shapes for newly-built buildings were provided combined with the characteristics of tornado wind fields. Fuzzy clustering and inverse closeness methods were used to evaluate the probability levels of tornado risks in various provinces based on classification and ranking. GIS was adopted to display the results. Finally, wind field single-vortex tornado was studied to discuss the optimized design of rural low-rise houses in Yancheng, Jiangsu as an example. This paper may provide enough data to support building and urban design in some specific regions.Keywords: tornado probability, computational fluid dynamics, fuzzy mathematics, optimal design
Procedia PDF Downloads 13611003 Indoor Thermal Comfort in Educational Buildings in the State of Kuwait
Authors: Sana El-Azzeh, Farraj Al-Ajmi, Abdulrahman Al-Aqqad, Mohamed Salem
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Thermal comfort is defined according to ANSI/ASHRAE Standard 55 as a condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation. Sustaining this standard of thermal comfort for occupants of buildings or other enclosures is one of the important goals of HVAC design engineers. This paper presents a study of thermal comfort and adaptive behaviors of occupants who occupies two locations at the campus of the Australian College of Kuwait. A longitudinal survey and field measurement were conducted to measure thermal comfort, adaptive behaviors, and indoor environment qualities. The study revealed that female occupants in the selected locations felt warmer than males and needed more air velocity and lower temperature.Keywords: indoor thermal comfort, educational facility, gender analysis, dry desert climate
Procedia PDF Downloads 15711002 An Evaluation of the Effects of Special Safeguards in Meat upon International Trade and the Brazilian Economy
Authors: Cinthia C. Costa, Heloisa L. Burnquist, Joaquim J. M. Guilhoto
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This study identified the impact of special agricultural safeguards (SSG) for the global market of meat and for the Brazilian economy. The tariff lines subject to SSG were selected and the period of analysis was 1995 (when the rules about the SSGs were established) to 2015 (more recent period for which there are notifications). The value of additional tariff was calculated for each of the most important tariff lines. The import volume and the price elasticities for imports were used to estimate the impacts of each additional tariff estimated on imports. Finally, the effect of Brazilian exports of meat without SSG taxes was calculated as well as its impact in the country’s economy by using an input-output matrix. The most important markets that applied SSGs were the U.S. for beef and European Union for poultry. However, the additional tariffs could be estimated in only two of the sixteen years that the U.S. applied SSGs on beef imports, suggesting that its use has been enforced when the average annual price has been higher than the trigger price level. The results indicated that the value of the bovine and poultry meat that could not be exported by Brazil due to SSGs to both markets (EU and the U.S.) was equivalent to BRL 804 million. The impact of this loss in trade was about: BRL 3.7 billion of the economy’s production value (at 2015 prices) and almost BRL 2 billion of the Brazilian Gross Domestic Product (GDP).Keywords: beef, poultry meat, SSG tariff, input-output matrix, Brazil
Procedia PDF Downloads 12111001 Gadjah Mada University Yogyakarta Indonesia as a Potential Destination for Education Tourism
Authors: Henry Prihanto Nugroho
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This paper suggests education tourism as an option into developing more sustainable mass tourism. Identifying the potential of education tourism and developing a sustainable packages will have an impact on social economic development in the area. Indonesia especially Yogyakarta can increase their tourism earnings by tapping into this growing market phenomenon. Educational tourism, a growing part in the world tourism market, has attracted great attention because of its direct impact on the community and as an alternative strategy for poverty alleviation. Tourism is considered as one of the main industries and sectors highly contributing to economic development in Indonesia especially in Yogyakarta, this region can be an ideal case for studying the issue of educational tourism in Universitas Gadjah Mada. This paper tries to introduce the educational tourism as an important alternative source of the economy accelerator in the context of Yogyakarta Indonesia. This paper also aims to discuss the education tourism potential at the University of Gadjah Mada, Yogyakarta Indonesia then to create and established an Education Tourism package at Gadjah Mada University. Education Tourism is a means to empower academics, local community, local businesses, and to improve the economic welfare. Methods: Focus group discussions, direct observation, survey and best practice method. Conclusion: There is a positive relationship between attitude, environmental impact, economic impact, and socio-cultural impacts and practice in the field when the potential is seized. The findings incorporate insights into the socio-cultural and economic potential of education tourism and practices related to community development at the University of Gadjah Mada, Yogyakarta Indonesia by creating an Education Tourism Packages that will suit the needs of the tourist. Educational tourism can create sustainable development for local communities, academic society, universities, and stakeholders.Keywords: education tourism, Gadjah Mada, sustainable, tourism
Procedia PDF Downloads 39611000 Impact of Fin Cross Section Shape on Potential Distribution of Nanoscale Trapezoidal FinFETs
Authors: Ahmed Nassim Moulai Khatir
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Fin field effect transistors (FinFETs) deliver superior levels of scalability than the classical structure of MOSFETs by offering the elimination of short channel effects. Modern FinFETs are 3D structures that rise above the planar substrate, but some of these structures have inclined surfaces, which results in trapezoidal cross sections instead of rectangular sections usually used. Fin cross section shape of FinFETs results in some device issues, like potential distribution performance. This work analyzes that impact with three-dimensional numeric simulation of several triple-gate FinFETs with various top and bottom widths of fin. Results of the simulation show that the potential distribution and the electrical field in the fin depend on the sidewall inclination angle.Keywords: FinFET, cross section shape, SILVACO, trapezoidal FinFETs
Procedia PDF Downloads 4710999 The Effect of Raindrop Kinetic Energy on Soil Erodibility
Authors: A. Moussouni, L. Mouzai, M. Bouhadef
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Soil erosion is a very complex phenomenon, resulting from detachment and transport of soil particles by erosion agents. The kinetic energy of raindrop is the energy available for detachment and transport by splashing rain. The soil erodibility is defined as the ability of soil to resist to erosion. For this purpose, an experimental study was conducted in the laboratory using rainfall simulator to study the effect of the kinetic energy of rain (Ec) on the soil erodibility (K). The soil used was a sandy agricultural soil of 62.08% coarse sand, 19.14% fine sand, 6.39% fine silt, 5.18% coarse silt and 7.21% clay. The obtained results show that the kinetic energy of raindrops evolves as a power law with soil erodibility.Keywords: erosion, runoff, raindrop kinetic energy, soil erodibility, rainfall intensity, raindrop fall velocity
Procedia PDF Downloads 50510998 Conical Spouted Bed Combustor for Combustion of Vine Shoots Wastes
Authors: M. J. San José, S. Alvarez, R. López
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In order to prove the applicability of a conical spouted bed combustor for the thermal exploitation of vineyard pruning wastes, the flow regimes of beds consisting of vine shoot beds and an inert bed were established under different operating conditions. The effect of inlet air temperature on the minimum spouted velocity was evaluated. Batch combustion of vine shoots in a conical spouted bed combustor was conducted at temperatures in the range 425-550 ºC with an inert bed. The experimental values of combustion efficiency of vine shoot calculated from the concentration the exhaust gases were assessed. The high experimental combustion efficiency obtained evidenced the proper suitability of the conical spouted bed combustor for the thermal combustion of vine shoots.Keywords: biomass wastes, thermal combustion, conical spouted beds, vineyard wastes
Procedia PDF Downloads 19910997 Balancing and Synchronization Control of a Two Wheel Inverted Pendulum Vehicle
Authors: Shiuh-Jer Huang, Shin-Ham Lee, Sheam-Chyun Lin
Abstract:
A two wheel inverted pendulum (TWIP) vehicle is built with two hub DC motors for motion control evaluation. Arduino Nano micro-processor is chosen as the control kernel for this electric test plant. Accelerometer and gyroscope sensors are built in to measure the tilt angle and angular velocity of the inverted pendulum vehicle. Since the TWIP has significantly hub motor dead zone and nonlinear system dynamics characteristics, the vehicle system is difficult to control by traditional model based controller. The intelligent model-free fuzzy sliding mode controller (FSMC) was employed as the main control algorithm. Then, intelligent controllers are designed for TWIP balance control, and two wheels synchronization control purposes.Keywords: balance control, synchronization control, two-wheel inverted pendulum, TWIP
Procedia PDF Downloads 39610996 Numerical Investigation of a Supersonic Ejector for Refrigeration System
Authors: Karima Megdouli, Bourhan Taschtouch
Abstract:
Supersonic ejectors have many applications in refrigeration systems. And improving ejector performance is the key to improve the efficiency of these systems. One of the main advantages of the ejector is its geometric simplicity and the absence of moving parts. This paper presents a theoretical model for evaluating the performance of a new supersonic ejector configuration for refrigeration system applications. The relationship between the flow field and the key parameters of the new configuration has been illustrated by analyzing the Mach number and flow velocity contours. The method of characteristics (MOC) is used to design the supersonic nozzle of the ejector. The results obtained are compared with those obtained by CFD. The ejector is optimized by minimizing exergy destruction due to irreversibility and shock waves. The optimization converges to an efficient optimum solution, ensuring improved and stable performance over the whole considered range of uncertain operating conditions.Keywords: supersonic ejector, theoretical model, CFD, optimization, performance
Procedia PDF Downloads 7610995 Experimental and Numerical Investigation of Flow Control Using a Novel Active Slat
Authors: Basman Elhadidi, Islam Elqatary, Osama Mohamady, Hesham Othman
Abstract:
An active slat is developed to increase the lift and delay the separation for a DU96-W180 airfoil. The active slat is a fixed slat that can be closed, fully opened or intermittently opened by a rotating vane depending on the need. Experimental results show that the active slat has reduced the mean pressure and increased the mean velocity on the suction side of the airfoil for all positive angles of attack, indicating an increase of lift. The experimental data and numerical simulations also show that the direction of actuator vane rotation can influence the mixing of the flow streams on the suction side and hence influence the aerodynamic performance.Keywords: active slat, flow control, DU96-W180 airfoil, flow streams
Procedia PDF Downloads 37810994 Social Media Use and Exercise Behaviors
Authors: Justin M. Swanson, Anna Nelson, Daniel Handysides, Patti Herring, Christopher Hill
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Not only may social media use have a psychological impact, but increased use may be tied to decreases in physical activity and influencing sedentary behaviors. Social media can be used to share physically active lifestyles and possibly influence others to participate. In contrast, social media use may have adverse effects by decreasing participation in exercise. This study used a qualitative design to examine the relationship between social media use and exercise patterns. Participants were asked questions about their social media habits and how it might impact their physical activity behaviors. Self-reported exercise seemed to increase after viewing others engage in relatable activities or viewing someone that has overcame challenges. To increase the likelihood of engaging in exercise, exercise related posts should be low in difficulty, require few materials, or displayed progress from the individual posting.Keywords: social media, exercise, physical activity, adults
Procedia PDF Downloads 26510993 Social Media Use’s Influence on Self-Perception
Authors: Bob Wang
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This study investigates the impact of social media usage on Chinese adolescents’ appearance anxiety. A total of 366 respondents were surveyed online about their self-perception regarding appearance and their social media usage. Each individual participant was asked about the type and frequency of social media usage as well as their opinion on statements regarding appearance anxiety. Participants were also asked to give short answers about their coping mechanism with appearance anxiety. Social media usage had a complex relationship with appearance anxiety, as most individuals acknowledged the appearance-related pressure generated by social media but also showed resilience towards appearance anxiety. Results suggest a wide impact of appearance anxiety on Chinese adolescents and highlight the person-specific resilience mechanisms adopted by those youths.Keywords: appearance anxiety, self-perception, social media, coping mechanisms
Procedia PDF Downloads 6710992 Prediction of the Tunnel Fire Flame Length by Hybrid Model of Neural Network and Genetic Algorithms
Authors: Behzad Niknam, Kourosh Shahriar, Hassan Madani
Abstract:
This paper demonstrates the applicability of Hybrid Neural Networks that combine with back propagation networks (BPN) and Genetic Algorithms (GAs) for predicting the flame length of tunnel fire A hybrid neural network model has been developed to predict the flame length of tunnel fire based parameters such as Fire Heat Release rate, air velocity, tunnel width, height and cross section area. The network has been trained with experimental data obtained from experimental work. The hybrid neural network model learned the relationship for predicting the flame length in just 3000 training epochs. After successful learning, the model predicted the flame length.Keywords: tunnel fire, flame length, ANN, genetic algorithm
Procedia PDF Downloads 643