Search results for: greenwashing behavior
4656 In-situ Monitoring of Residual Stress Behavior-Temperature Profiles in Transparent Polyimide/Tetrapod Zinc Oxide Whisker Composites
Authors: Ki-Ho Nam, Haksoo Han
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Tetrapod zinc oxide whiskers (TZnO-Ws) were successfully synthesized by a thermal oxidation method. A series of transparent polyimide (PI)/TZnO-W composites were successfully synthesized via a solution-blending method. The structural and morphological features of TZnO-Ws and PI/TZnO-W composites were characterized by Fourier transform infrared spectroscopy (FT-IR), wide-angle X-Ray diffraction (WAXD), and field emission scanning electron microscope (FE-SEM). Dynamic stress behaviors were investigated in-situ during thermal imidization of the soft-baked PI/TZnO-W composite precursor and thermally cured composite films using a thin film stress analyzer (TFSA) by wafer bending technique. The PI/TZnO-W composite films exhibited an optical transparency greater than 80% at 550 nm (≤ 0.5 wt% TZnO-W content), a low coefficient of thermal expansion (CTE), and enhanced glass transition temperature. However, the thermal decomposition temperature decreased as the TZnO-W content increased. The water diffusion coefficient and water uptake of the PI/TZNO-W composite films were obtained by best fits to a Fickian diffusion model. The water resistance capacity of PI was greatly enhanced and moisture diffusion in the pure PI was retarded by incorporating the TZnO-W. The PI composite films based on TZNO-W resultantly may have potential applications in optoelectronic manufacturing processes as a flexible transparent substrate.Keywords: polyimide (PI), tetrapod ZnO whisker (TZnO-W), transparent, dynamic stress behavior, water resistance
Procedia PDF Downloads 5174655 Estimation of Geotechnical Parameters by Comparing Monitoring Data with Numerical Results: Case Study of Arash–Esfandiar-Niayesh Under-Passing Tunnel, Africa Tunnel, Tehran, Iran
Authors: Aliakbar Golshani, Seyyed Mehdi Poorhashemi, Mahsa Gharizadeh
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The under passing tunnels are strongly influenced by the soils around. There are some complexities in the specification of real soil behavior, owing to the fact that lots of uncertainties exist in soil properties, and additionally, inappropriate soil constitutive models. Such mentioned factors may cause incompatible settlements in numerical analysis with the obtained values in actual construction. This paper aims to report a case study on a specific tunnel constructed by NATM. The tunnel has a depth of 11.4 m, height of 12.2 m, and width of 14.4 m with 2.5 lanes. The numerical modeling was based on a 2D finite element program. The soil material behavior was modeled by hardening soil model. According to the field observations, the numerical estimated settlement at the ground surface was approximately four times more than the measured one, after the entire installation of the initial lining, indicating that some unknown factors affect the values. Consequently, the geotechnical parameters are accurately revised by a numerical back-analysis using laboratory and field test data and based on the obtained monitoring data. The obtained result confirms that typically, the soil parameters are conservatively low-estimated. And additionally, the constitutive models cannot be applied properly for all soil conditions.Keywords: NATM tunnel, initial lining, laboratory test data, numerical back-analysis
Procedia PDF Downloads 3584654 Intervening between Family Functioning and Depressive Symptoms: Effect of Deprivation of Liberty, Self-Efficacy and Differentiation of Self
Authors: Jasna Hrncic
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Poor family relations predict depression, but also to other mental health issues. Mediating effect of self-efficacy and differentiation of self and moderating effect of decreased accessibility and/or success of other adaptive and defensive mechanisms for overcoming social disadvantages could explain depression as a specific outcome of dysfunctional family relations. The present study analyzes the mediation effect of self-efficacy and differentiation of self from poor family functioning to depressive symptoms and the moderation effect of deprivation of liberty on the listed mediation effect. Deprivation of liberty has, as a general consequence, a decreased accessibility and/or success of many adaptive and defensive mechanisms. It is hypothesized that: 1) self-efficacy and differentiation of self will mediate between family functioning and depressiveness in the total sample, and 2) deprivation of liberty will moderate the stated relations. Cross-sectional study was conducted among 323 male juveniles in Serbia divided in three groups: 98 adolescents deprived of their liberty due to antisocial behavior (incarcerated antisocial group - IAG), 121 adolescents with antisocial behavior in their natural setting (antisocial control group - CAG) and 105 adolescents in general population (general control group - CGG). The CAG was included along with GCG to control the possible influence that comorbidity of antisocial behavior and depressiveness could have on results. Instruments for family relations assessment were: for a whole family of origin the emotional exchange scale and individuation scale from GRADIR by Knezevic, and for a relationship with mother PCS-YSR and CRPBI by barber, and intimacy, rejection, sacrifice, punishment, demands, control and internal control by Opacic and Kos. Differentiation of self (DOS) is measured by emotional self scale (Opacic), self-efficacy (SE) by general incompetence scale by Bezinovic, and depression by BDI (Back), CES-D (Radloff) and D6R (Momirovic). Two-path structural equation modeling based on most commonly reported fit indices, showed that the mediation model had unfavorable fit to our data for total sample [(χ2 (1, N = 324) = 13.73); RMSEA= .20 (90% CI= [.12, .30]); CFI= .98; NFI= .97; AIC=31.73]. Path model provided an adequate fit to the data only for AIG - and not to the data from ACG and GCG. SE and DOS mediated the relationship between PFF and depressiveness. Test of the indirect effects revealed that 23.85% of PFF influences on depressiveness is mediated by these two mediators (the quotient of mediated effect = .24). Test of specific indirect effects showed that SE mediates 22.17%, while DOS mediates 1.67% of PFF influence on depressiveness. Lack of expected mediation effect could be explained by missing other potential mediators (i.e., relationship with that father, social skills, self-esteem) and lower variability of both predictor and criterion variable due to their low levels on the whole sample and on control subsamples. Results suggested that inaccessibility and/or successfulness of other adaptive and defensive mechanisms for overcoming social disadvantages has a strong impact on the mediation effect of self/efficacy and differentiation of self from poor family functioning to depressive symptoms. Further researches could include other potential mediators and a sample of clinically depressed people.Keywords: antisocial behavior, mediating effect, moderating effect, natural setting, incarceration
Procedia PDF Downloads 1124653 The Effect of Health Program on the Fitness Ability of Abnormal BMI University Students
Authors: Hui-Fang Lee, Meng-Chu Liu, Wen-Chi Lu, Hsuan-Jung Hsieh
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The purpose of the study was to examine the effect of health program on the fitness ability of abnormal BMI students of Ching-Yun University of Science and Technology. In order to achieve this purpose, self-regulation theory and dietary education were applied, and the effect of 10-week sports activities and three-day diet records on pre-test and post-test of fitness activities was analyzed. There were 40 original participants. Then, nine people who were with normal BMI, low attendance or unfinished fitness test were eliminated from this research. The valid samples were 31 (77.5%) participants. The fitness activities included sit-bending, one minute sit-up, standing long jump, and three-minute stage boarding. The averages of three-day diet records were compared, and differences of pre-test and post-test of the four fitness activities were analyzed with paired-samples t test. The results showed that there was a significant difference between pre-test and post of male students’ BMI and one minute sit-up. Females’ sit-bending and one minute sit-up had the same effect. Females had high fat intake in three-day diet records. The research showed that the use of self-regulation theory and dietary education, the implementation of sports activities and three-day diet records could significantly enhance the physical fitness indicators or effects. While in the course of sports, we should guide students to think about the gap between self-behavior and ideal behavior, then realize the main reasons and improving methods, and finally go towards the goal and improve the effect of physical fitness.Keywords: self-regulation theory, dietary education, three-day diet records, physical fitness
Procedia PDF Downloads 3124652 Pilot Trial of Evidence-Based Integrative Group Therapy to Improve Executive Functioning among Adults: Implications for Community Mental Health and Training Clinics
Authors: B. Parchem, M. Watanabe, D. Modrakovic, L. Mathew, A. Franklin, M. Cao, R. E. Broudy
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Objective: Executive functioning (EF) deficits underlie several mental health diagnoses including ADHD, anxiety, and depression. Community mental health clinics face extensive waitlists for services with many referrals involving EF deficits. A pilot trial of a four-week group therapy was developed using key components from Cognitive-Behavioral Therapy (CBT), Dialectical Behavior Therapy (DBT), and mindfulness with an aim to improve EF skills and offer low-fee services. Method: Eight adults (M = 34.5) waiting for services at a community clinic were enrolled in a four-week group therapy at an in-house training clinic for doctoral trainees. Baseline EF, pre-/post-intervention ADHD and distress symptoms, group satisfaction, and curriculum helpfulness were assessed. Results: Downward trends in ADHD and distress symptoms pre/post-intervention were not significant. Favorable responses on group satisfaction and helpfulness suggest clinical utility. Conclusion: Preliminary pilot data from a brief group therapy to improve EF may be an efficacious, acceptable, and feasible intervention for adults waiting for services at community mental health and training clinics where there are high demands and limits to services and staffs.Keywords: executive functioning, cognitive-behavioral therapy, dialectical behavior therapy, mindfulness, adult group therapy
Procedia PDF Downloads 1554651 Stigmatization of Individuals Who Receive Mental Health Treatment and the Role of Social Media: A Cross-Generational Cohort Design and Extension
Authors: Denise Ben-Porath, Tracy Masterson
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In the past, individuals who struggled with and sought treatment for mental health difficulties were stigmatized. However, the current generation holds more open attitudes around mental health issues. Indeed, public figures such as Demi Lovato, Naomi Osaka, and Simone Biles have taken to social media to break the silence around mental health, discussing their own struggles and the benefits of treatment. Thus, there is considerable reason to believe that this generation would hold fewer stigmatizing attitudes toward mental health difficulties and treatment compared to previous ones. In this study, we explored possible changes in stigma on mental health diagnosis and treatment seeking behavior between two generations: Gen Z, the current generation, and Gen X, those born between 1965-1980. It was hypothesized that Gen Z would hold less stigmatizing views on mental illness than Gen X. To examine possible changes in stigma attitudes between these two generations, we conducted a cross-generational cohort design by using the same methodology employed 20 years ago from the Ben-Porath (2002) study. Thus, participants were randomly assigned to read one of the following four case vignettes employed in the Ben-Porath (2002) study: (a) “Tom” who has received psychotherapy due to depression (b) “Tom” who has been depressed but received no psychological help, (c) “Tom” who has received medical treatment due to a back pain, or (d) “Tom” who had a back pain but did not receive medical attention. After reading the vignette, participants rated “Tom” on various personality dimensions using the IFQ Questionnaire and answered questions about their frequency of social media use and willingness to seek mental health treatment on a scale from 1-10. Identical to the results 20 years prior, a significant main effect was found for diagnosis with “Tom” being viewed in more negative terms when he was described as having depression vs. a medical condition (back pain) [F (1, 376) = 126.53, p < .001]. However, in the study conducted 20 years earlier, a significant interaction was found between diagnosis and help-seeking behavior [F (1, 376) = 8.28, p < .005]. Specifically, “Tom” was viewed in the most negative terms when described as depressed and seeking treatment. Alternatively, the current study failed to find a significant interaction between depression and help seeking behavior. These findings suggest that while individuals who hold a mental health diagnosis may still be stigmatized as they were 20 years prior, seeking treatment for mental health issues may be less so. Findings are discussed in the context of social media use and its impact on destigmatization.Keywords: stigma, mental illness, help-seeking, social media
Procedia PDF Downloads 684650 Understanding Mental Constructs of Language and Emotion
Authors: Sakshi Ghai
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The word ‘emotion’ has been microscopically studied through psychological, anthropological and biological lenses and have indubitably been one of the most researched concepts as, in all situations and reactions that constitute human life, emotions form the very niche of our mutual existence. While understanding the social aspects of cognition, one can realize that emotions are deeply interwoven with language and thereby are pivotal in inducing human actions and behavior. The society or the outward social structure is the result of the inward psychological structure of our human relationships, for the individual is the result of the total experience, knowledge and conduct of man. The aim of this paper is threefold: first, to establish the relation between mental representations of emotions and its neuropsychological connection with language on a conscious and sub-conscious level; secondly, to describe how innate, basic and higher cognitive emotions affect the constantly changing state of an agent and peruse its assistance in determining the moral compass within all beings. Lastly, in the course of this paper, the concept of the architecture of mind is explored considering how it has developed an ability to display adaptive emotional states and responses, which are in sync with the language of thought. For every response to the social environment is so deeply determined by the very social milieu in which one is situated, language has a fundamental role in constructing emotions and articulating behavior. Being linguistic beings, we tend to associate emotion, feelings and other aspects of inwards mental states intrinsically with the language we use. This paper aims to devise a discursive approach to understand how emotions are fabricated, intertwined with the mental constructs further expressed and communicated through the various units of language.Keywords: mental representation, emotion, language, psychology
Procedia PDF Downloads 2814649 Influence of Surface Preparation Effects on the Electrochemical Behavior of 2098-T351 Al–Cu–Li Alloy
Authors: Rejane Maria P. da Silva, Mariana X. Milagre, João Victor de S. Araujo, Leandro A. de Oliveira, Renato A. Antunes, Isolda Costa
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The Al-Cu-Li alloys are advanced materials for aerospace application because of their interesting mechanical properties and low density when compared with conventional Al-alloys. However, Al-Cu-Li alloys are susceptible to localized corrosion. The near-surface deformed layer (NSDL) induced by the rolling process during the production of the alloy and its removal by polishing can influence on the corrosion susceptibility of these alloys. In this work, the influence of surface preparation effects on the electrochemical activity of AA2098-T351 (Al–Cu–Li alloy) was investigated using a correlation between surface chemistry, microstructure, and electrochemical activity. Two conditions were investigated, polished and as-received surfaces of the alloy. The morphology of the two types of surfaces was investigated using confocal laser scanning microscopy (CLSM) and optical microscopy. The surface chemistry was analyzed by X-ray Photoelectron Spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS). Global electrochemical techniques (potentiodynamic polarization and EIS technique) and a local electrochemical technique (Localized Electrochemical Impedance Spectroscopy-LEIS) were used to examine the electrochemical activity of the surfaces. The results obtained in this study showed that in the as-received surface, the near-surface deformed layer (NSDL), which is composed of Mg-rich bands, influenced the electrochemical behavior of the alloy. The results showed higher electrochemical activity to the polished surface condition compared to the as-received one.Keywords: Al-Cu-Li alloys, surface preparation effects, electrochemical techniques, localized corrosion
Procedia PDF Downloads 1484648 Discovering Causal Structure from Observations: The Relationships between Technophile Attitude, Users Value and Use Intention of Mobility Management Travel App
Authors: Aliasghar Mehdizadeh Dastjerdi, Francisco Camara Pereira
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The increasing complexity and demand of transport services strains transportation systems especially in urban areas with limited possibilities for building new infrastructure. The solution to this challenge requires changes of travel behavior. One of the proposed means to induce such change is multimodal travel apps. This paper describes a study of the intention to use a real-time multi-modal travel app aimed at motivating travel behavior change in the Greater Copenhagen Region (Denmark) toward promoting sustainable transport options. The proposed app is a multi-faceted smartphone app including both travel information and persuasive strategies such as health and environmental feedback, tailoring travel options, self-monitoring, tunneling users toward green behavior, social networking, nudging and gamification elements. The prospective for mobility management travel apps to stimulate sustainable mobility rests not only on the original and proper employment of the behavior change strategies, but also on explicitly anchoring it on established theoretical constructs from behavioral theories. The theoretical foundation is important because it positively and significantly influences the effectiveness of the system. However, there is a gap in current knowledge regarding the study of mobility-management travel app with support in behavioral theories, which should be explored further. This study addresses this gap by a social cognitive theory‐based examination. However, compare to conventional method in technology adoption research, this study adopts a reverse approach in which the associations between theoretical constructs are explored by Max-Min Hill-Climbing (MMHC) algorithm as a hybrid causal discovery method. A technology-use preference survey was designed to collect data. The survey elicited different groups of variables including (1) three groups of user’s motives for using the app including gain motives (e.g., saving travel time and cost), hedonic motives (e.g., enjoyment) and normative motives (e.g., less travel-related CO2 production), (2) technology-related self-concepts (i.e. technophile attitude) and (3) use Intention of the travel app. The questionnaire items led to the formulation of causal relationships discovery to learn the causal structure of the data. Causal relationships discovery from observational data is a critical challenge and it has applications in different research fields. The estimated causal structure shows that the two constructs of gain motives and technophilia have a causal effect on adoption intention. Likewise, there is a causal relationship from technophilia to both gain and hedonic motives. In line with the findings of the prior studies, it highlights the importance of functional value of the travel app as well as technology self-concept as two important variables for adoption intention. Furthermore, the results indicate the effect of technophile attitude on developing gain and hedonic motives. The causal structure shows hierarchical associations between the three groups of user’s motive. They can be explained by “frustration-regression” principle according to Alderfer's ERG (Existence, Relatedness and Growth) theory of needs meaning that a higher level need remains unfulfilled, a person may regress to lower level needs that appear easier to satisfy. To conclude, this study shows the capability of causal discovery methods to learn the causal structure of theoretical model, and accordingly interpret established associations.Keywords: travel app, behavior change, persuasive technology, travel information, causality
Procedia PDF Downloads 1324647 Cognitive Behaviour Drama: Playful Method to Address Fears in Children on the Higher-End of the Autism Spectrum
Authors: H.Karnezi, K. Tierney
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Childhood fears that persist over time and interfere with the children’s normal functioning may have detrimental effects on their social and emotional development. Cognitive behavior therapy is considered highly effective in treating fears and anxieties. However, given that many childhood fears are based on fantasy, the applicability of CBT may be hindered by cognitive immaturity. Furthermore, a lack of motivation to engage in therapy is another commonly encountered obstacle. The purpose of this study was to introduce and evaluate a more developmentally appropriate intervention model, specifically designed to provide phobic children with the motivation to overcome their fears. To this end, principles and techniques from cognitive and behavior therapies are incorporated into the ‘Drama in Education’ model. The Cognitive Behaviour Drama (CBD) method involves using the phobic children’s creativity to involve them in the therapeutic process. The children are invited to engage in exciting fictional scenarios tailored around their strengths and special interests. Once their commitment to the drama is established, a problem that they will feel motivated to solve is introduced. To resolve it, the children will have to overcome a number of obstacles culminating in an in vivo confrontation with the fear stimulus. The study examined the application of the CBD model in three single cases. Results in all three cases shown complete elimination of all fear-related symptoms. Preliminary results justify further evaluation of the Cognitive Behaviour Drama model. It is time and cost-effective, ensuring the clients' immediate engagement in the therapeutic process.Keywords: phobias, autism, intervention, drama
Procedia PDF Downloads 1194646 Finite Difference Modelling of Temperature Distribution around Fire Generated Heat Source in an Enclosure
Authors: A. A. Dare, E. U. Iniegbedion
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Industrial furnaces generally involve enclosures of fire typically initiated by the combustion of gases. The fire leads to temperature distribution inside the enclosure. A proper understanding of the temperature and velocity distribution within the enclosure is often required for optimal design and use of the furnace. This study was therefore directed at numerical modeling of temperature distribution inside an enclosure as typical in a furnace. A mathematical model was developed from the conservation of mass, momentum and energy. The stream function-vorticity formulation of the governing equations was solved by an alternating direction implicit (ADI) finite difference technique. The finite difference formulation obtained were then developed into a computer code. This was used to determine the temperature, velocities, stream function and vorticity. The effect of the wall heat conduction was also considered, by assuming a one-dimensional heat flow through the wall. The computer code (MATLAB program) developed was used for the determination of the aforementioned variables. The results obtained showed that the transient temperature distribution assumed a uniform profile which becomes more chaotic with increasing time. The vertical velocity showed increasing turbulent behavior with time, while the horizontal velocity assumed decreasing laminar behavior with time. All of these behaviours were equally reported in the literature. The developed model has provided understanding of heat transfer process in an industrial furnace.Keywords: heat source, modelling, enclosure, furnace
Procedia PDF Downloads 2504645 Numerical Modal Analysis of a Multi-Material 3D-Printed Composite Bushing and Its Application
Authors: Paweł Żur, Alicja Żur, Andrzej Baier
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Modal analysis is a crucial tool in the field of engineering for understanding the dynamic behavior of structures. In this study, numerical modal analysis was conducted on a multi-material 3D-printed composite bushing, which comprised a polylactic acid (PLA) outer shell and a thermoplastic polyurethane (TPU) flexible filling. The objective was to investigate the modal characteristics of the bushing and assess its potential for practical applications. The analysis involved the development of a finite element model of the bushing, which was subsequently subjected to modal analysis techniques. Natural frequencies, mode shapes, and damping ratios were determined to identify the dominant vibration modes and their corresponding responses. The numerical modal analysis provided valuable insights into the dynamic behavior of the bushing, enabling a comprehensive understanding of its structural integrity and performance. Furthermore, the study expanded its scope by investigating the entire shaft mounting of a small electric car, incorporating the 3D-printed composite bushing. The shaft mounting system was subjected to numerical modal analysis to evaluate its dynamic characteristics and potential vibrational issues. The results of the modal analysis highlighted the effectiveness of the 3D-printed composite bushing in minimizing vibrations and optimizing the performance of the shaft mounting system. The findings contribute to the broader field of composite material applications in automotive engineering and provide valuable insights for the design and optimization of similar components.Keywords: 3D printing, composite bushing, modal analysis, multi-material
Procedia PDF Downloads 914644 Origamic Forms: A New Realm in Improving Acoustical Environment
Authors: Mostafa Refat Ismail, Hazem Eldaly
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The adaptation of architecture design to building function is getting highly needed in contemporary designs, especially with the great progression in design methods and tools. This, in turn, requires great flexibility in design strategies, as well as a wider spectrum of space settings to achieve the required environment that special activities imply. Acoustics is an essential factor influencing cognitive acts and behavior as well as, on the extreme end, the physical well-being inside a space. The complexity of this constrain is fueled up by the extended geometric dimensions of multipurpose halls, making acoustic adequateness a great concern that could not easily be achieved for each purpose. To achieve a performance oriented acoustic environment, various parametric shaped false ceilings based on origami folded notion are simulated. These parametric origami shapes are able to fold and unfold forming an interactive structure that changes the mutual acoustic environment according to the geometric shapes' position and its changing exposed surface areas. The mobility of the facets in the origami surface can stretch up the range from a complete plain surface to an unfolded element where a considerable amount of absorption is added to the space. The behavior of the parametric origami shapes are being modeled employing a ray tracing computer simulation package for various shapes topology. The conclusion shows a great variation in the acoustical performance due to the variation in folding faces of the origami surfaces, which cause different reflections and consequently large variations in decay curves.Keywords: parametric, origami, acoustics, architecture
Procedia PDF Downloads 2824643 The Positive Impact of COVID-19 on the Level of Investments of U.S. Retail Investors: Evidence from a Quantitative Online Survey and Ordered Probit Analysis
Authors: Corina E. Niculaescu, Ivan Sangiorgi, Adrian R. Bell
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The COVID-19 pandemic has been life-changing in many aspects of people’s daily and social lives, but has it also changed attitudes towards investments? This paper explores the effect of the COVID-19 pandemic on retail investors’ levels of investments in the U.S. during the first COVID-19 wave in summer 2020. This is an unprecedented health crisis, which could lead to changes in investment behavior, including irrational behavior in retail investors. As such, this study aims to inform policymakers of what happened to investment decisions during the COVID-19 pandemic so that they can protect retail investors during extreme events like a global health crisis. The study aims to answer two research questions. First, was the level of investments affected by the COVID-19 pandemic, and if so, why? Second, how were investments affected by retail investors’ personal experience with COVID-19? The research analysis is based on primary survey data collected on the Amazon Mechanical Turk platform from a representative sample of U.S. respondents. Responses were collected between the 15th of July and 28th of August 2020 from 1,148 U.S. retail investors who hold mutual fund investments and a savings account. The research explores whether being affected by COVID-19, change in the level of savings, and risk capacity can explain the change in the level of investments by using regression analysis. The dependent variable is changed in investments measured as decrease, no change, and increase. For this reason, the methodology used is ordered probit regression models. The results show that retail investors in the U.S. increased their investments during the first wave of COVID-19, which is unexpected as investors are usually more cautious in crisis times. Moreover, the study finds that those who were affected personally by COVID-19 (e.g., tested positive) were more likely to increase their investments, which is irrational behavior and contradicts expectations. An increase in the level of savings and risk capacity was also associated with increased investments. Overall, the findings show that having personal experience with a health crisis can have an impact on one’s investment decisions as well. Those findings are important for both retail investors and policymakers, especially now that online trading platforms have made trading easily accessible to everyone. There are risks and potential irrational behaviors associated with investment decisions during times of crisis, and it is important that retail investors are aware of them before making financial decisions.Keywords: COVID-19, financial decision-making, health crisis retail investors, survey
Procedia PDF Downloads 1834642 The Extent of Virgin Olive-Oil Prices' Distribution Revealing the Behavior of Market Speculators
Authors: Fathi Abid, Bilel Kaffel
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The olive tree, the olive harvest during winter season and the production of olive oil better known by professionals under the name of the crushing operation have interested institutional traders such as olive-oil offices and private companies such as food industry refining and extracting pomace olive oil as well as export-import public and private companies specializing in olive oil. The major problem facing producers of olive oil each winter campaign, contrary to what is expected, it is not whether the harvest will be good or not but whether the sale price will allow them to cover production costs and achieve a reasonable margin of profit or not. These questions are entirely legitimate if we judge by the importance of the issue and the heavy complexity of the uncertainty and competition made tougher by a high level of indebtedness and the experience and expertise of speculators and producers whose objectives are sometimes conflicting. The aim of this paper is to study the formation mechanism of olive oil prices in order to learn about speculators’ behavior and expectations in the market, how they contribute by their industry knowledge and their financial alliances and the size the financial challenge that may be involved for them to build private information hoses globally to take advantage. The methodology used in this paper is based on two stages, in the first stage we study econometrically the formation mechanisms of olive oil price in order to understand the market participant behavior by implementing ARMA, SARMA, GARCH and stochastic diffusion processes models, the second stage is devoted to prediction purposes, we use a combined wavelet- ANN approach. Our main findings indicate that olive oil market participants interact with each other in a way that they promote stylized facts formation. The unstable participant’s behaviors create the volatility clustering, non-linearity dependent and cyclicity phenomena. By imitating each other in some periods of the campaign, different participants contribute to the fat tails observed in the olive oil price distribution. The best prediction model for the olive oil price is based on a back propagation artificial neural network approach with input information based on wavelet decomposition and recent past history.Keywords: olive oil price, stylized facts, ARMA model, SARMA model, GARCH model, combined wavelet-artificial neural network, continuous-time stochastic volatility mode
Procedia PDF Downloads 3324641 Feature Analysis of Predictive Maintenance Models
Authors: Zhaoan Wang
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Research in predictive maintenance modeling has improved in the recent years to predict failures and needed maintenance with high accuracy, saving cost and improving manufacturing efficiency. However, classic prediction models provide little valuable insight towards the most important features contributing to the failure. By analyzing and quantifying feature importance in predictive maintenance models, cost saving can be optimized based on business goals. First, multiple classifiers are evaluated with cross-validation to predict the multi-class of failures. Second, predictive performance with features provided by different feature selection algorithms are further analyzed. Third, features selected by different algorithms are ranked and combined based on their predictive power. Finally, linear explainer SHAP (SHapley Additive exPlanations) is applied to interpret classifier behavior and provide further insight towards the specific roles of features in both local predictions and global model behavior. The results of the experiments suggest that certain features play dominant roles in predictive models while others have significantly less impact on the overall performance. Moreover, for multi-class prediction of machine failures, the most important features vary with type of machine failures. The results may lead to improved productivity and cost saving by prioritizing sensor deployment, data collection, and data processing of more important features over less importance features.Keywords: automated supply chain, intelligent manufacturing, predictive maintenance machine learning, feature engineering, model interpretation
Procedia PDF Downloads 1224640 An Analysis of Younger Consumers’ Perceptions, Purchasing Decisions, and Pro-Environmental Behavior: A Market Experiment on Green Advertising
Authors: Mokhlisur Rahman
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Consumers have developed a sense of responsibility in the past decade, reflecting on their purchasing behavior after viewing an advertisement. Consumers tend to buy ideal products that enable them to be judged by their close network in the opinion world. In such value considerations, any information that feeds consumers' desire for social status helps, which becomes capital for educating consumers on the importance of purchasing green products for manufacturing companies. Companies' effort in manufacturing green products to get high conversion demands a good deal of promotion with quality information and engaging representation. Additionally, converting people from traditional to eco-friendly products requires innovative alternatives to replace the existing product. Considering consumers' understanding of products and their purchasing behavior, it becomes essential for the brands to know the extent to which consumers' level of awareness of the ecosystem is to make them more responsive to green products. Another is brand image plays a vital role in consumers' perception regarding the credibility of the claim regarding the product. Brand image is a significant positive influence on the younger generation, and younger generations tend to engage more in pro-environmental behavior, including purchasing sustainable products. For example, Adidas senses the necessity of satisfying consumers with something that brings more profits and serves the planet. Several of their eco-friendly products are already in the market, and one is UltraBOOST DNA parley, made from 3D-printed recycled ocean waste. As a big brand image, Adidas has leveraged an interest among the younger generation by incorporating sustainability into its advertising. Therefore, influential brands' effort in the sustainable revolution through engaging advertisement makes it more prominent by educating consumers about the reason behind launching the product. This study investigates younger consumers' attitudes toward sustainability, brand recognition, exposure to green advertising, willingness to receive more green advertising, purchasing green products, and motivation. The study conducts a market experiment by creating two video advertisements: a sustainable product video advertisement and a non-sustainable product video advertisement. Both the videos have similar content design and the same length of 2 minutes, but the messages are different based on the identical product type college bags. The first video advertisement promotes eco-friendly college bags made from biodegradable raw materials, and the second promotes non-sustainable college bags made from plastics. After viewing the videos, consumers make purchasing decisions and complete an online survey to collect their attitudes toward sustainable products. The study finds the importance of a sense of responsibility to the consumers for climate change issues. Also, it empowers people to take a step, even small, and increases environmental awareness. This study provides companies with the knowledge to participate in sustainable product launches by collecting consumers' perceptions and attitudes toward green products. Also, it shows how important it is to build a brand's image for the younger generation.Keywords: brand-image, environment, green-advertising, sustainability, younger-consumer
Procedia PDF Downloads 594639 Incorporating Morality Standards in eLearning Process at INU
Authors: Khader Musbah Titi
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In this era, traditional education systems do not meet the new challenges created by emerging technologies. On the other hand, eLearning offers all the necessary tools to meet these challenges. Using the Internet has brought numerous benefits to most educational institutions; it has also stretched traditional problems of plagiarism, cheating, stealing, vandalism, and spying into the cyberspace. This research discusses these issues in an eLearning environment. It attempts to provide suggestions and possible solutions to some of these issues. The main aim of this research is to conduct a survey at Irbid National University (INU), one of the oldest and biggest universities in Jordan, to study information related to moral and ethical issues in e-learning environment that affect the construction of the students’ characters in the future. The study will focus on student’s behavior and actions through the Internet using Learning Management System (LMS). Another aim of this research is to analyze the opinions of the instructors and last year students at INU about ethical behavior and interaction through LMS. The results show that educational institutes that use LMS should focus on student character development along with field knowledge. According to disadvantages, the results of the study showed that most of students behave unethically in their online activities (cheating, plagiarism, copy/paste etc.) while studying online courses through LMS. The result showed that instructors play a major role in the character development of students. The result also showed that academic institute must have variant mechanisms and strict policy in LMS to control unethical actions of students.Keywords: LMS, cyber ethics, e-learning, IT ethics, students’ behaviors
Procedia PDF Downloads 2374638 Synthesis and Characterization of Lactic Acid Grafted TiO2 Nanocomposites
Authors: Qasar Saleem
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The aim of this project was to synthesize and analyze Polylactic acid-grafted TiO2 nanocomposite. When dispersed at the nanoscale TiO2 can behave as see through transparent UV filters and thermomechanical materials. The synthesis plan involved three stages. First, dispersion of TiO2 white powder in water/ethanol solvent system. Second grafting TiO2 surface by oligomers of lactic acid aimed at changing its surface features. Third polymerization of lactic acid monomer with grafted TiO2 in the presence of anhydrous stannous chloride as a catalyst. Polylactic acid grafted-TiO2 nanocomposite was synthesized by melt polycondensation in situ of lactic acid onto titanium oxide (TiO2) nanoparticles surface. The product was characterized by TGA, DSC, FTIR, and UV analysis and degradation observation. An idea regarding bonds between the grafting polymer and surface modified titanium oxide nanoparticles. Characteristics peaks of Ti–carbonyl bond, the related intensities of the Fourier transmission absorption peaks of graft composite, the melt and decomposition behavior stages of Polylactic acid-grafted TiO2 nanocomposite convinced that oligomers of polylactic acid were chemically bonded on the surface of TiO2 nanoparticles. Through grafting polylactic acid, the Polylactic acid grafted -TiO2 sample shown good absorption in UV region and degradation behavior under normal atmospheric conditions. Regaining transparency of degraded white opaque Polylactic acid-grafted TiO2 nanocomposite on heating was another character. Polylactic acid-grafted TiO2 nanocomposite will be a potential candidate in future for biomedical, UV shielding and environment friendly material.Keywords: condensation, nanocomposites, oligomers, polylactic
Procedia PDF Downloads 2044637 Rheological and Computational Analysis of Crude Oil Transportation
Authors: Praveen Kumar, Satish Kumar, Jashanpreet Singh
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Transportation of unrefined crude oil from the production unit to a refinery or large storage area by a pipeline is difficult due to the different properties of crude in various areas. Thus, the design of a crude oil pipeline is a very complex and time consuming process, when considering all the various parameters. There were three very important parameters that play a significant role in the transportation and processing pipeline design; these are: viscosity profile, temperature profile and the velocity profile of waxy crude oil through the crude oil pipeline. Knowledge of the Rheological computational technique is required for better understanding the flow behavior and predicting the flow profile in a crude oil pipeline. From these profile parameters, the material and the emulsion that is best suited for crude oil transportation can be predicted. Rheological computational fluid dynamic technique is a fast method used for designing flow profile in a crude oil pipeline with the help of computational fluid dynamics and rheological modeling. With this technique, the effect of fluid properties including shear rate range with temperature variation, degree of viscosity, elastic modulus and viscous modulus was evaluated under different conditions in a transport pipeline. In this paper, two crude oil samples was used, as well as a prepared emulsion with natural and synthetic additives, at different concentrations ranging from 1,000 ppm to 3,000 ppm. The rheological properties was then evaluated at a temperature range of 25 to 60 °C and which additive was best suited for transportation of crude oil is determined. Commercial computational fluid dynamics (CFD) has been used to generate the flow, velocity and viscosity profile of the emulsions for flow behavior analysis in crude oil transportation pipeline. This rheological CFD design can be further applied in developing designs of pipeline in the future.Keywords: surfactant, natural, crude oil, rheology, CFD, viscosity
Procedia PDF Downloads 4354636 Manifestation of Behavioral and Emotional Disturbances and Perceived Coping Strategies of Earthquake Survived Children
Authors: Mahwish Rabia, Najma Najam
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The present study was conducted to identify emotional and behavioral disturbances among earthquake survived children and the perceived coping strategies of affected children. In the present study, a sample of 50 children (6-16 years) belonging to badly affected areas (earthquake) was selected from different camps in Islamabad. Child Behavioral Checklist (CBCL) and Rotter Incomplete Sentence Blank (RISB) interpretations were used to assess variety of emotional and behavioral patterns, and Child Coping Strategies Checklist (CCSC) was used to assess the perceived coping strategies of affected children. Results showed that some of the frequent emotional/behavioral reactions exhibited by children like withdrawal, anxiety\depression, aggression and attention seeking behavior. Whereas gender-based comparisons indicated that female children showed more internalizing behavioral patterns (withdrawn, somatic complaints) as compared to male children who exhibited more externalizing emotions (aggression, delinquent behavior).Coping strategies in which male children tried to adopt Positive Cognitive Restructuring and for distracting attention they used distraction strategies of coping. It is concluded that significant negative emotional and behavioral reactions are exhibited by the earthquake affected children. Male children adopt coping strategies more as compared to female children. The study identifies the negative emotional and behavioral reactions towards trauma, which can be helpful for identifying the problematic area for counseling and therapeutic interventions for these children.Keywords: behavioural disturbances, emotional disturbances, coping strategies, earthquake, children
Procedia PDF Downloads 4744635 Study of the Protection of Induction Motors
Authors: Bencheikh Abdellah
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In this paper, we present a mathematical model dedicated to the simulation breaks bars in a three-phase cage induction motor. This model is based on a mesh circuit representing the rotor cage. The tested simulation allowed us to demonstrate the effectiveness of this model to describe the behavior of the machine in a healthy state, failure.Keywords: AC motors, squirrel cage, diagnostics, MATLAB, SIMULINK
Procedia PDF Downloads 4304634 Analytical and Numerical Results for Free Vibration of Laminated Composites Plates
Authors: Mohamed Amine Ben Henni, Taher Hassaine Daouadji, Boussad Abbes, Yu Ming Li, Fazilay Abbes
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The reinforcement and repair of concrete structures by bonding composite materials have become relatively common operations. Different types of composite materials can be used: carbon fiber reinforced polymer (CFRP), glass fiber reinforced polymer (GFRP) as well as functionally graded material (FGM). The development of analytical and numerical models describing the mechanical behavior of structures in civil engineering reinforced by composite materials is necessary. These models will enable engineers to select, design, and size adequate reinforcements for the various types of damaged structures. This study focuses on the free vibration behavior of orthotropic laminated composite plates using a refined shear deformation theory. In these models, the distribution of transverse shear stresses is considered as parabolic satisfying the zero-shear stress condition on the top and bottom surfaces of the plates without using shear correction factors. In this analysis, the equation of motion for simply supported thick laminated rectangular plates is obtained by using the Hamilton’s principle. The accuracy of the developed model is demonstrated by comparing our results with solutions derived from other higher order models and with data found in the literature. Besides, a finite-element analysis is used to calculate the natural frequencies of laminated composite plates and is compared with those obtained by the analytical approach.Keywords: composites materials, laminated composite plate, finite-element analysis, free vibration
Procedia PDF Downloads 2844633 The Impact of Online Advertising on Generation Y’s Purchase Decision in Malaysia
Authors: Mui Joo Tang, Eang Teng Chan
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Advertising is commonly used to foster sales and reputation of an institution. It is at first the growth of print advertising that has increased the population and number of periodicals of newspaper and its circulation. The rise of Internet and online media has somehow blurred the role of media and advertising though the intention is still to reach out to audience and to increase sales. The relationship between advertising and audience on a product purchase through persuasion has been developing from print media to online media. From the changing media environment and audience, it is the concern of this research to study the impact of online advertising to such a relationship cycle. The content of online advertisements is much of text, multimedia, photo, audio and video. The messages of such content format may indeed bring impacts to its audience and its credibility. This study is therefore reflecting the effectiveness of online advertisement and its influences on generation Y in their purchasing behavior. This study uses Media Dependency Theory to analyze the relationship between the impact of online advertisement and media usage pattern of generation Y. Hierarchy of Effectiveness Model is used as a marketing communication model to study the effectiveness of advertising and further to determine the impact of online advertisement on generation Y in their purchasing decision making. This research uses online survey to reach out the sample of generation Y. The results have shown that online advertisements do not affect much on purchase decision making even though generation Y relies much on the media content including online advertisement for its information and believing in its credibility. There are few other external factors that may interrupt the effectiveness of online advertising. The very obvious influence of purchasing behavior is actually derived from the peers.Keywords: generation Y, purchase decision, print media, online advertising, persuasion
Procedia PDF Downloads 5204632 Evaluation of the Need for Seismic Retrofitting of the Foundation of a Five Story Steel Building Because of Adding of a New Story
Authors: Mohammadreza Baradaran, F. Hamzezarghani
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Every year in different points of the world it occurs with different strengths and thousands of people lose their lives because of this natural phenomenon. One of the reasons for destruction of buildings because of earthquake in addition to the passing of time and the effect of environmental conditions and the wearing-out of a building is changing the uses of the building and change the structure and skeleton of the building. A large number of structures that are located in earthquake bearing areas have been designed according to the old quake design regulations which are out dated. In addition, many of the major earthquakes which have occurred in recent years, emphasize retrofitting to decrease the dangers of quakes. Retrofitting structural quakes available is one of the most effective methods for reducing dangers and compensating lack of resistance caused by the weaknesses existing. In this article the foundation of a five-floor steel building with the moment frame system has been evaluated for quakes and the effect of adding a floor to this five-floor steel building has been evaluated and analyzed. The considered building is with a metallic skeleton and a piled roof and clayed block which after addition of a floor has increased to a six-floor foundation of 1416 square meters, and the height of the sixth floor from ground state has increased 18.95 meters. After analysis of the foundation model, the behavior of the soil under the foundation and also the behavior of the body or element of the foundation has been evaluated and the model of the foundation and its type of change in form and the amount of stress of the soil under the foundation for some of the composition has been determined many times in the SAFE software modeling and finally the need for retrofitting of the building's foundation has been determined.Keywords: seismic, rehabilitation, steel building, foundation
Procedia PDF Downloads 2684631 A Pilot Randomized Controlled Trial of a Physical Activity Intervention in a Low Socioeconomic Population: Focus on Mental Contrasting with Implementation Intentions
Authors: Shaun G. Abbott, Rebecca C. Reynolds, John B. F. de Wit
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Low physical activity (PA) levels are a major public health concern in Australia. There is some evidence that PA interventions can increase PA levels via various methods, including online delivery. Low Socioeconomic Status (SES) people participate in less PA than the rest of the population, partly due to poor self-regulation behaviors associated with socioeconomic characteristics. Interventions that involve a particular method of self-regulation, Mental Contrasting with Implementation Intentions (MCII), has regularly achieved healthy behavior change, but few studies focus on PA behavior outcomes and no studies examining the effect of MCII on the PA behaviors of low SES people has been done. In this study, a pilot randomized controlled trial (RCT) will deliver MCII for PA behavior change to individuals of relative disadvantage for the first time. The current pilot study will predict sample size for a future full RCT and test the hypothesis that sedentary participants from areas of relative socioeconomic disadvantage of Sydney, who learn the MCII technique will be more physically active, have improved anthropometry and psychological indicators at the completion of a 12-week intervention compared to baseline and control. Eligible participants of relative socioeconomic disadvantage will be randomly assigned to either the ‘PA Information Plus MCII Intervention Group’ or a ‘PA Information-Only Control Group’. Both groups will attend a baseline and 12-week face-to-face consultation; where PA, anthropometric and psychological data will be gathered. The intervention group will be guided through an MCII session at the baseline appointment to establish a PA goal to aim to achieve over 12 weeks. Other than these baseline and 12-week consultations, all participant interaction will occur online. All participants will receive a ‘Fitbit’ accelerometer to record objectively. PA as a daily step count, along with a PA diary for the duration of the study. PA data will be recorded on a personalized online spreadsheet. Both groups will receive a standard PA information email at weeks 2, 4, and 8. The intervention group will also receive scripted follow-up online appointments to discuss goal progress. The current pilot study is in recruitment stage with findings to be presented at the conference in December if selected.Keywords: implementation intentions, mental contrasting, motivation, pedometer, physical activity, socioeconomic
Procedia PDF Downloads 2994630 Estimation of the Seismic Response Modification Coefficient in the Superframe Structural System
Authors: Ali Reza Ghanbarnezhad Ghazvini, Seyyed Hamid Reza Mosayyebi
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In recent years, an earthquake has occurred approximately every five years in certain regions of Iran. To mitigate the impact of these seismic events, it is crucial to identify and thoroughly assess the vulnerability of buildings and infrastructure, ensuring their safety through principled reinforcement. By adopting new methods of risk assessment, we can effectively reduce the potential risks associated with future earthquakes. In our research, we have observed that the coefficient of behavior in the fourth chapter is 1.65 for the initial structure and 1.72 for the Superframe structure. This indicates that the Superframe structure can enhance the strength of the main structural members by approximately 10% through the utilization of super beams. Furthermore, based on the comparative analysis between the two structures conducted in this study, we have successfully designed a stronger structure with minimal changes in the coefficient of behavior. Additionally, this design has allowed for greater energy dissipation during seismic events, further enhancing the structure's resilience to earthquakes. By comprehensively examining and reinforcing the vulnerability of buildings and infrastructure, along with implementing advanced risk assessment techniques, we can significantly reduce casualties and damages caused by earthquakes in Iran. The findings of this study offer valuable insights for civil engineering professionals in the field of structural engineering, aiding them in designing safer and more resilient structures.Keywords: modal pushover analysis, response modification factor, high-strength concrete, concrete shear walls, high-rise building
Procedia PDF Downloads 1344629 Effect of Temperature and CuO Nanoparticle Concentration on Thermal Conductivity and Viscosity of a Phase Change Material
Authors: V. Bastian Aguila, C. Diego Vasco, P. Paula Galvez, R. Paula Zapata
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The main results of an experimental study of the effect of temperature and nanoparticle concentration on thermal conductivity and viscosity of a nanofluid are shown. The nanofluid was made by using octadecane as a base fluid and CuO spherical nanoparticles of 75 nm (MkNano). Since the base fluid is a phase change material (PCM) to be used in thermal storage applications, the engineered nanofluid is referred as nanoPCM. Three nanoPCM were prepared through the two-step method (2.5, 5.0 and 10.0%wv). In order to increase the stability of the nanoPCM, the surface of the CuO nanoparticles was modified with sodium oleate, and it was verified by IR analysis. The modified CuO nanoparticles were dispersed by using an ultrasonic horn (Hielscher UP50H) during one hour (amplitude of 180 μm at 50 W). The thermal conductivity was measured by using a thermal properties analyzer (KD2-Pro) in the temperature range of 30ºC to 40ºC. The viscosity was measured by using a Brookfield DV2T-LV viscosimeter to 30 RPM in the temperature range of 30ºC to 55ºC. The obtained results for the nanoPCM showed that thermal conductivity is almost constant in the analyzed temperature range, and the viscosity decreases non-linearly with temperature. Respect to the effect of the nanoparticle concentration, both thermal conductivity and viscosity increased with nanoparticle concentration. The thermal conductivity raised up to 9% respect to the base fluid, and the viscosity increases up to 60%, in both cases for the higher concentration. Finally, the viscosity measurements for different rotation speeds (30 RPM - 80 RPM) exhibited that the addition of nanoparticles modifies the rheological behavior of the base fluid, from a Newtonian to a viscoplastic (Bingham) or shear thinning (power-law) non-Newtonian behavior.Keywords: NanoPCM, thermal conductivity, viscosity, non-Newtonian fluid
Procedia PDF Downloads 4124628 Characteristic of Oxidation Resistant High-Entropy Alloys for Application in Zero-Emission Technologies
Authors: Wojciech J. Nowak, Natalia Maciaszek, Marcin Drajewicz
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A constant requirement to reduce greenhouse gas emissions in combination with the desire to increase gas turbine efficiency results in a continuous trend to increase the operating temperature of gas turbines. An increase in operating temperature will result in lower fuel consumption, and a higher combustion temperature will result in lower pollution release. Moreover, there is a strong trend for hydrogen to be used as an alternative and clean fuel. However, using hydrogen or hydrogen-rich fuel results in a higher combustion temperature, as well as an increase in the water vapor content in the exhaust gases. Commonly used Ni-base alloys have their limits. Moreover, the presence of water vapor worsens the oxidation behavior of Ni-based alloys at a high temperature. Therefore, a new brand of materials is demanded to be used in gas turbines operated with hydrogen-rich fuel. High-entropy alloys (HEAs) seem to be very promising materials to replace commonly used Ni-based alloys. HEAs are the group of materials consisting of at least five main equiatomic elements. These alloys can be doped by other elements in amounts less than 5 at. % in total. Thus, in the present study, NiCoCrAlFe-X alloys are studied in terms of oxidation behavior during exposure to dry and wet atmospheres up to 1000 h. NiCoCrAlFe-X alloys are doped with minor alloying elements in amounts ranging from 1-5 at.%. The effect of the chemical composition on oxidation resistance in dry and wet atmospheres will be shown and discussed.Keywords: high entropy alloys, oxidation resistance, hydrogen fuel, water vapor
Procedia PDF Downloads 364627 Perforation Analysis of the Aluminum Alloy Sheets Subjected to High Rate of Loading and Heated Using Thermal Chamber: Experimental and Numerical Approach
Authors: A. Bendarma, T. Jankowiak, A. Rusinek, T. Lodygowski, M. Klósak, S. Bouslikhane
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The analysis of the mechanical characteristics and dynamic behavior of aluminum alloy sheet due to perforation tests based on the experimental tests coupled with the numerical simulation is presented. The impact problems (penetration and perforation) of the metallic plates have been of interest for a long time. Experimental, analytical as well as numerical studies have been carried out to analyze in details the perforation process. Based on these approaches, the ballistic properties of the material have been studied. The initial and residual velocities laser sensor is used during experiments to obtain the ballistic curve and the ballistic limit. The energy balance is also reported together with the energy absorbed by the aluminum including the ballistic curve and ballistic limit. The high speed camera helps to estimate the failure time and to calculate the impact force. A wide range of initial impact velocities from 40 up to 180 m/s has been covered during the tests. The mass of the conical nose shaped projectile is 28 g, its diameter is 12 mm, and the thickness of the aluminum sheet is equal to 1.0 mm. The ABAQUS/Explicit finite element code has been used to simulate the perforation processes. The comparison of the ballistic curve was obtained numerically and was verified experimentally, and the failure patterns are presented using the optimal mesh densities which provide the stability of the results. A good agreement of the numerical and experimental results is observed.Keywords: aluminum alloy, ballistic behavior, failure criterion, numerical simulation
Procedia PDF Downloads 305