Search results for: traditional models
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10914

Search results for: traditional models

2754 Unraveling the Complexities of Competitive Aggressiveness: A Qualitative Exploration in the Oil and Gas Industry

Authors: Salim Al Harthy, Alexandre A. Bachkirov

Abstract:

This study delves into the complexities of competitive aggressiveness in the oil and gas industry, focusing on the characteristics of the identified competitive actions. The current quantitative research on competitive aggressiveness lacks agreement on the connection between antecedents and outcomes, prompting a qualitative investigation. To address this gap, the research utilizes qualitative interviews with CEOs from Oman's oil and gas service industry to explore the dynamics of competitive aggressiveness. Using Noklenain's typology, the study categorizes and analyzes identified actions, shedding light on the spectrum of competitive behaviors within the industry. Notably, actions predominantly fall under the "Bring about" and "Preserve" elements, with a notable absence in the "Forebear" and "Destroy" categories, possibly linked to the study's focus on service-oriented businesses. The study also explores the detectability of actions, revealing that "Bring about" actions are detectable, while those in "Preserve" and "Suppress" are not. This challenges conventional definitions of competitive aggressiveness, suggesting that not all actions are readily detectable despite being considered competitive. The presence of non-detectable actions introduces complexity to measurement methods reliant on visible empirical data. Moreover, the study contends that companies can adopt an aggressive competitive approach without directly challenging rivals. This challenges traditional views and emphasizes the innovative and entrepreneurial aspects of actions not explicitly aimed at competitors. By not revealing strategic intentions, such actions put rivals at a disadvantage, underscoring the need for a nuanced understanding of competitive aggressiveness. In summary, the lack of consensus in existing literature regarding the relationship between antecedents and outcomes in competitive aggressiveness is addressed. The study reveals a spectrum of detectable and undetectable actions, posing challenges in measurement and emphasizing the need for alternative methods to assess undetectable actions in competitive behavior. This research contributes to a more nuanced understanding of competitive aggressiveness, acknowledging the diverse actions shaping a company's strategic positioning in dynamic business environments.

Keywords: competitive aggressiveness, qualitative exploration, noklenain's typology, oil and gas industry

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2753 Engineering of Reagentless Fluorescence Biosensors Based on Single-Chain Antibody Fragments

Authors: Christian Fercher, Jiaul Islam, Simon R. Corrie

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Fluorescence-based immunodiagnostics are an emerging field in biosensor development and exhibit several advantages over traditional detection methods. While various affinity biosensors have been developed to generate a fluorescence signal upon sensing varying concentrations of analytes, reagentless, reversible, and continuous monitoring of complex biological samples remains challenging. Here, we aimed to genetically engineer biosensors based on single-chain antibody fragments (scFv) that are site-specifically labeled with environmentally sensitive fluorescent unnatural amino acids (UAA). A rational design approach resulted in quantifiable analyte-dependent changes in peak fluorescence emission wavelength and enabled antigen detection in vitro. Incorporation of a polarity indicator within the topological neighborhood of the antigen-binding interface generated a titratable wavelength blueshift with nanomolar detection limits. In order to ensure continuous analyte monitoring, scFv candidates with fast binding and dissociation kinetics were selected from a genetic library employing a high-throughput phage display and affinity screening approach. Initial rankings were further refined towards rapid dissociation kinetics using bio-layer interferometry (BLI) and surface plasmon resonance (SPR). The most promising candidates were expressed, purified to homogeneity, and tested for their potential to detect biomarkers in a continuous microfluidic-based assay. Variations of dissociation kinetics within an order of magnitude were achieved without compromising the specificity of the antibody fragments. This approach is generally applicable to numerous antibody/antigen combinations and currently awaits integration in a wide range of assay platforms for one-step protein quantification.

Keywords: antibody engineering, biosensor, phage display, unnatural amino acids

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2752 Price Compensation Mechanism with Unmet Demand for Public-Private Partnership Projects

Authors: Zhuo Feng, Ying Gao

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Public-private partnership (PPP), as an innovative way to provide infrastructures by the private sector, is being widely used throughout the world. Compared with the traditional mode, PPP emerges largely for merits of relieving public budget constraint and improving infrastructure supply efficiency by involving private funds. However, PPP projects are characterized by large scale, high investment, long payback period, and long concession period. These characteristics make PPP projects full of risks. One of the most important risks faced by the private sector is demand risk because many factors affect the real demand. If the real demand is far lower than the forecasting demand, the private sector will be got into big trouble because operating revenue is the main means for the private sector to recoup the investment and obtain profit. Therefore, it is important to study how the government compensates the private sector when the demand risk occurs in order to achieve Pareto-improvement. This research focuses on price compensation mechanism, an ex-post compensation mechanism, and analyzes, by mathematical modeling, the impact of price compensation mechanism on payoff of the private sector and consumer surplus for PPP toll road projects. This research first investigates whether or not price compensation mechanisms can obtain Pareto-improvement and, if so, then explores boundary conditions for this mechanism. The research results show that price compensation mechanism can realize Pareto-improvement under certain conditions. Especially, to make the price compensation mechanism accomplish Pareto-improvement, renegotiation costs of the government and the private sector should be lower than a certain threshold which is determined by marginal operating cost and distortionary cost of the tax. In addition, the compensation percentage should match with the price cut of the private investor when demand drops. This research aims to provide theoretical support for the government when determining compensation scope under the price compensation mechanism. Moreover, some policy implications can also be drawn from the analysis for better risk-sharing and sustainability of PPP projects.

Keywords: infrastructure, price compensation mechanism, public-private partnership, renegotiation

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2751 Anti Oxidant Ayurvedic Rasyan Herbs Concept to Disease Managment

Authors: Mohammed Khalil Ur Rahman, Khanita Aammatullh

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Rasayana is one of the eight clinical specialities of classical Ayurveda The disease preventive and health promotive approach of ‘Ayurveda’, which takes into consideration the whole body, mind and spirit while dealing with the maintenance of health, promotion of health and treating ailments is holistic and finds increasing acceptability in many regions of the world. Ancient Ayurvedic physicians had developed certain dietary and therapeutic measures to arrest/delay ageing and rejuvenating whole functional dynamics of the body system. This revitalization and rejuvenation is known as the ‘Rasayan chikitsa’ (rejuvenation therapy). Traditionally, Rasayana drugs are used against a plethora of seemingly diverse disorders with no pathophysiological connections according to modern medicine. Though, this group of plants generally possesses strong antioxidant activity, only a few have been investigated in detail. Over about 100 disorders like rheumatoid arthritis, hemorrhagic shock, CVS disorders, cystic fibrosis, metabolic disorders, neurodegenerative diseases, gastrointestinal ulcerogenesis and AIDS have been reported as reactive oxygen species mediated. In this review, the role of free radicals in these diseases has been briefly reviewed. ‘Rasayana’ plants with potent antioxidant activity have been reviewed for their traditional uses, and mechanism of antioxidant action. Fifteen such plants have been dealt with in detail and some more plants with less work have also been reviewed briefly The Rasayanas are rejuvenators, nutritional supplements and possess strong antioxidant activity. They also have antagonistic actions on the oxidative stressors, which give rise to the formation of different free radicals. Ocimum sanctum, Tinospora cordifolia, Emblica officinalis, Convolvulus pluricaulis, Centella asiatica, Bacopa monniera, Withania somnifera, Triphala rasayana, Chyawanprash, Brahma rasayana are very important rasayanas which are described in ayurveda and proved by new researches.

Keywords: rasayana, antioxidant activity, Bacopa monniera, Withania somnifera Triphala, chyawanprash

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2750 Teaching Method for a Classroom of Students at Different Language Proficiency Levels: Content and Language Integrated Learning in a Japanese Culture Classroom

Authors: Yukiko Fujiwara

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As a language learning methodology, Content and Language Integrated Learning (CLIL) has become increasingly prevalent in Japan. Most CLIL classroom practice and its research are conducted in EFL fields. However, much less research has been done in the Japanese language learning setting. Therefore, there are still many issues to work out using CLIL in the Japanese language teaching (JLT) setting. it is expected that more research will be conducted on both authentically and academically. Under such circumstances, this is one of the few classroom-based CLIL researches experiments in JLT and aims to find an effective course design for a class with students at different proficiency levels. The class was called ‘Japanese culture A’. This class was offered as one of the elective classes for International exchange students at a Japanese university. The Japanese proficiency level of the class was above the Japanese Language Proficiency Test Level N3. Since the CLIL approach places importance on ‘authenticity’, the class was designed with materials and activities; such as books, magazines, a film and TV show and a field trip to Kyoto. On the field trip, students experienced making traditional Japanese desserts, by receiving guidance directly from a Japanese artisan. Through the course, designated task sheets were used so the teacher could get feedback from each student to grasp what the class proficiency gap was. After reading an article on Japanese culture, students were asked to write down the words they did not understand and what they thought they needed to learn. It helped both students and teachers to set learning goals and work together for it. Using questionnaires and interviews with students, this research examined whether the attempt was effective or not. Essays they wrote in class were also analyzed. The results from the students were positive. They were motivated by learning authentic, natural Japanese, and they thrived setting their own personal goals. Some students were motivated to learn Japanese by studying the language and others were motivated by studying the cultural context. Most of them said they learned better this way; by setting their own Japanese language and culture goals. These results will provide teachers with new insight towards designing class materials and activities that support students in a multilevel CLIL class.

Keywords: authenticity, CLIL, Japanese language and culture, multilevel class

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2749 Early Depression Detection for Young Adults with a Psychiatric and AI Interdisciplinary Multimodal Framework

Authors: Raymond Xu, Ashley Hua, Andrew Wang, Yuru Lin

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During COVID-19, the depression rate has increased dramatically. Young adults are most vulnerable to the mental health effects of the pandemic. Lower-income families have a higher ratio to be diagnosed with depression than the general population, but less access to clinics. This research aims to achieve early depression detection at low cost, large scale, and high accuracy with an interdisciplinary approach by incorporating clinical practices defined by American Psychiatric Association (APA) as well as multimodal AI framework. The proposed approach detected the nine depression symptoms with Natural Language Processing sentiment analysis and a symptom-based Lexicon uniquely designed for young adults. The experiments were conducted on the multimedia survey results from adolescents and young adults and unbiased Twitter communications. The result was further aggregated with the facial emotional cues analyzed by the Convolutional Neural Network on the multimedia survey videos. Five experiments each conducted on 10k data entries reached consistent results with an average accuracy of 88.31%, higher than the existing natural language analysis models. This approach can reach 300+ million daily active Twitter users and is highly accessible by low-income populations to promote early depression detection to raise awareness in adolescents and young adults and reveal complementary cues to assist clinical depression diagnosis.

Keywords: artificial intelligence, COVID-19, depression detection, psychiatric disorder

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2748 Meta-analysis of Technology Acceptance for Mobile and Digital Libraries in Academic Settings

Authors: Nosheen Fatima Warraich

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One of the most often used models in information system (IS) research is the technology acceptance model (TAM). This meta-analysis aims to measure the relationship between TAM variables, Perceived Ease of Use (PEOU), and Perceived Usefulness (PU) with users’ attitudes and behavioral intention (BI) in mobile and digital libraries context. It also examines the relationship of external variables (information quality and system quality) with TAM variables (PEOU and PU) in digital libraries settings. This meta-analysis was performed through PRISMA-P guidelines. Four databases (Google Scholar, Web of Science, Scopus, and LISTA) were utilized for searching, and the search was conducted according to defined criteria. The findings of this study revealed a large effect size of PU and PEOU with BI. There was also a large effect size of PU and PEOU with attitude. A medium effect size was found between SysQ -> PU, InfoQ-> PU, and SysQ -> PEOU. However, there was a small effect size between InfoQ and PEOU. It fills the literature gap and also confirms that TAM is a valid model for the acceptance and use of technology in mobile and digital libraries context. Thus, its findings would be helpful for developers and designers in designing and developing mobile library apps. It will also be beneficial for library authorities and system librarians in designing and developing digital libraries in academic settings.

Keywords: technology acceptance model (tam), perceived ease of use, perceived usefulness, information quality, system quality, meta-analysis, systematic review, digital libraries, and mobile library apps.

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2747 I Don’t Know How I Got Here and I Don’t Know How to Get out of It: Understanding Male Pre-service Early Child Education Teachers’ Construction of Professional Identity

Authors: Sabika Khalid, Endale Fantahun Tadesse

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Unlike other professional sectors, a great deal of studies has addressed the overwhelming gender disparity phenomena in the early childhood education (ECE) workforce, which is acknowledged for the dominance of women over men teachers. The irony of ECE being a gendered working environment is not only observed in societies that are ruled by gender roles but also in Western countries that claim to margin the gender gap in several professions. The participation of male teachers in ECE across most countries ranged from 1% to 3% of the total preschool or kindergarten teachers. When it comes to a dynamic Chinese society tempered with a deep-rooted tradition and cultural ideology, the ECE has no less place for males, and males have a low place for ECE. According to the Ministry of Education of China (2020), there are over 5 million kindergarten teachers and staff members, while only 2.3% are accounted for male teachers. The traditional gender-based discourse asserts that giving care and guidance for young children related to nurturing ‘mothering’ labels the profession in ECE as women’s work derived from originated from their ‘naturality.’ Although a large volume of evidence sheds light on the cause for low male teachers, the perception of parents, female teachers working with male teachers, and the experience of male teachers working in ECE, less is known and understood before being a teacher. Hence, this study argues that the promotion of the involvement of male teachers in light of their masculinity identity asset in the children's learning environment is comprehended to understand the construction of male student teachers' (preservice) professional identity during early childhood teacher training that allows obtaining substantial evidence that provides a feasible and robust implication in the preparation of competent and professional male preschool teachers that understand, cherish, and bring harmony in Chinese ECE through professionalism socialization with the stakeholders. This study intended to reveal male ECE preservice teachers’ knowledge of their professional identity, i.e., how they perceive themselves as a teacher and what factors agents these perceptions towards their professional identity.

Keywords: male teachers, Early Childhood Education (ECE), self-identity, perception of stakeholders

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2746 Design of Effective Decoupling Point in Build-To-Order Systems: Focusing on Trade-Off Relation between Order-To-Delivery Lead Time and Work in Progress

Authors: Zhiyong Li, Hiroshi Katayama

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Since 1990s, e-commerce and internet business have been grown gradually over the word and customers tend to express their demand attributes in terms of specification requirement on parts, component, product structure etc. This paper deals with designing effective decoupling points for build to order systems under e-commerce environment, which can be realized through tradeoff relation analysis between two major criteria, customer order lead time and value of work in progress. These KPIs are critical for successful BTO business, namely time-based service effectiveness on coping with customer requirements for the first issue and cost effective ness with risk aversive operations for the second issue. Approach of this paper consists of investigation of successful business standing for BTO scheme, manufacturing model development of this scheme, quantitative evaluation of proposed models by calculation of two KPI values under various decoupling point distributions and discussion of the results brought by pattern of decoupling point distribution, where some cases provide the pareto optimum performances. To extract the relevant trade-off relation between considered KPIs among 2-dimensional resultant performance, useful logic developed by former research work, i.e. Katayama and Fonseca, is applied. Obtained characteristics are evaluated as effective information for managing BTO manufacturing businesses.

Keywords: build-to-order (BTO), decoupling point, e-commerce, order-to-delivery lead time (ODLT), work in progress (WIP)

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2745 Sludge Densification: Emerging and Efficient Way to Look at Biological Nutrient Removal Treatment

Authors: Raj Chavan

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Currently, there are over 14,500 Water Resource Recovery Facilities (WRRFs) in the United States, with ~35% of them having some type of nutrient limits in place. These WRRFs account for about 1% of overall power demand and 2% of total greenhouse gas emissions (GHG) in the United States and contribute for 10 to 15% of the overall nutrient load to surface rivers in the United States. The evolution of densification technologies toward more compact and energy-efficient nutrient removal processes has been impacted by a number of factors. Existing facilities that require capacity expansion or biomass densification for higher treatability within the same footprint are being subjected to more stringent requirements relating to nutrient removal prior to surface water discharge. Densification of activated sludge has received recent widespread interest as a means for achieving process intensification and nutrient removal at WRRFs. At the core of the technology are the aerobic sludge granules where the biological processes occur. There is considerable interest in the prospect of producing granular sludge in continuous (or traditional) activated sludge processes (CAS) or densification of biomass by moving activated sludge flocs to a denser aggregate of biomass as a highly effective technique of intensification. This presentation will provide a fundamental understanding of densification by presenting insights and practical issues. The topics that will be discussed include methods used to generate and retain densified granules; the mechanisms that allow biological flocs to densify; the role that physical selectors play in the densification of biological flocs; some viable ways for managing biological flocs that have become densified; effects of physical selection design parameters on the retention of densified biological flocs and finally some operational solutions for customizing the flocs and granules required to meet performance and capacity targets. In addition, it will present some case studies where biological and physical parameters were used to generate aerobic granular sludge in the continuous flow system.

Keywords: densification, aerobic granular sludge, nutrient removal, intensification

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2744 Spirometric Reference Values in 236,606 Healthy, Non-Smoking Chinese Aged 4–90 Years

Authors: Jiashu Shen

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Objectives: Spirometry is a basic reference for health evaluation which is widely used in clinical. Previous reference of spirometry is not applicable because of drastic changes of social and natural circumstance in China. A new reference values for the spirometry of the Chinese population is extremely needed. Method: Spirometric reference value was established using the statistical modeling method Generalized Additive Models for Location, Scale and Shape for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, and maximal mid-expiratory flow (MMEF). Results: Data from 236,606 healthy non-smokers aged 4–90 years was collected from the MJ Health Check database. Spirometry equations for FEV1, FVC, MMEF, and FEV1/FVC were established, including the predicted values and lower limits of normal (LLNs) by sex. The predictive equations that were developed for the spirometric results elaborated the relationship between spirometry and age, and they eliminated the effects of height as a variable. Most previous predictive equations for Chinese spirometry were significantly overestimated (to be exact, with mean differences of 22.21% in FEV1 and 31.39% in FVC for males, along with differences of 26.93% in FEV1 and 35.76% in FVC for females) or underestimated (with mean differences of -5.81% in MMEF and -14.56% in FEV1/FVC for males, along with a difference of -14.54% in FEV1/FVC for females) the results of lung function measurements as found in this study. Through cross-validation, our equations were established as having good fit, and the means of the measured value and the estimated value were compared, with good results. Conclusions: Our study updates the spirometric reference equations for Chinese people of all ages and provides comprehensive values for both physical examination and clinical diagnosis.

Keywords: Chinese, GAMLSS model, reference values, spirometry

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2743 Perception of Mass Media Usage in Educational Development of Rural Communities in Nigeria

Authors: Aniekan James Akpan, Inemesit Akpan Umoren, Uduak Iwok

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From prehistoric and primitive cultures, education was seen as a process of culture transmission by way of guiding children into becoming good members of their local communities. Even in modern cultures, education is seen as a systematic discipline aimed at cultivating genuine values to improve oneself and society. Without education, the chances of realizing the desired vision are marred as it is believed that nations that invest much in education are able to reap the desired benefits technologically, economically, socially, politically, and otherwise. In this sense, the moulding of character is considered the primary purpose of education, and until the audience of mass media through its various vehicles is seen as tools for improving the overall development of society. It is believed that a media-friendly person is likely to perform better than someone who is less friendly. This work, therefore, examines the role media play in educational development. As highlighted by the study, a summary of the functions of media shows that they widen horizon by acting as a liberating force, breaking distance, bonds, and transforming a traditional society into a modern one. With the use of technological development theory, agenda-setting theory as well as uses and gratification theory and multiple intelligence theory, the work identifies different ways in which mass media help in educational development and draws attention to the audience’s perception of media functions in terms of educational development. With a survey method and a population of 6,903,321 people, the work sampled 220 respondents using purposive technique drawn from rural communities in the South-South region of Nigeria. The work concludes that mass media are potent vehicles for teaching and learning and therefore recommends that government should provide basic infrastructures to the rural communities to aid full utilization of media potentials in educational development and equally urge media owners and practitioners to as a matter of urgency increase coverage time on issues bordering on education as it is done for political and other issues.

Keywords: educational, development, media usage, perception

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2742 Opportunities and Challenges for Decarbonizing Steel Production by Creating Markets for ‘Green Steel’ Products

Authors: Hasan Muslemani, Xi Liang, Kathi Kaesehage, Francisco Ascui, Jeffrey Wilson

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The creation of a market for lower-carbon steel products, here called ‘green steel’, has been identified as an important means to support the introduction of breakthrough emission reduction technologies into the steel sector. However, the definition of what ‘green’ entails in the context of steel production, the implications on the competitiveness of green steel products in local and international markets, and the necessary market mechanisms to support their successful market penetration remain poorly explored. This paper addresses this gap by holding semi-structured interviews with international sustainability experts and commercial managers from leading steel trade associations, research institutes and steelmakers. Our findings show that there is an urgent need to establish a set of standards to define what ‘greenness’ means in the steelmaking context; standards that avoid market disruptions, unintended consequences, and opportunities for greenwashing. We also highlight that the introduction of green steel products will have implications on product competitiveness on three different levels: 1) between primary and secondary steelmaking routes, 2) with traditional, lesser green steel, and 3) with other substitutable materials (e.g. cement and plastics). This paper emphasises the need for steelmakers to adopt a transitional approach in deploying different low-carbon technologies, based on their stage of technological maturity, applicability in certain country contexts, capacity to reduce emissions over time, and the ability of the investment community to support their deployment. We further identify market mechanisms to support green steel production, including carbon border adjustments and public procurement, highlighting a need for implementing a combination of complementary policies to ensure the products’ roll-out. The study further shows that the auto industry is a likely candidate for green steel consumption, where a market would be supported by price premiums paid by willing consumers, such as those of high-end luxury vehicles.

Keywords: green steel, decarbonisation, business model innovation, market analysis

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2741 The Performance Improvement of Solar Aided Power Generation System by Introducing the Second Solar Field

Authors: Junjie Wu, Hongjuan Hou, Eric Hu, Yongping Yang

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Solar aided power generation (SAPG) technology has been proven as an efficient way to make use of solar energy for power generation purpose. In an SAPG plant, a solar field consisting of parabolic solar collectors is normally used to supply the solar heat in order to displace the high pressure/temperature extraction steam. To understand the performance of such a SAPG plant, a new simulation model was developed by the authors recently, in which the boiler was treated, as a series of heat exchangers unlike other previous models. Through the simulations using the new model, it was found the outlet properties of reheated steam, e.g. temperature, would decrease due to the introduction of the solar heat. The changes make the (lower stage) turbines work under off-design condition. As a result, the whole plant’s performance may not be optimal. In this paper, the second solar filed was proposed to increase the inlet temperature of steam to be reheated, in order to bring the outlet temperature of reheated steam back to the designed condition. A 600MW SAPG plant was simulated as a case study using the new model to understand the impact of the second solar field on the plant performance. It was found in the study, the 2nd solar field would improve the plant’s performance in terms of cycle efficiency and solar-to-electricity efficiency by 1.91% and 6.01%. The solar-generated electricity produced by per aperture area under the design condition was 187.96W/m2, which was 26.14% higher than the previous design.

Keywords: solar-aided power generation system, off-design performance, coal-saving performance, boiler modelling, integration schemes

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2740 Co-Creating an International Flipped Faculty Development Model: A US-Afghan Case Study

Authors: G. Alex Ambrose, Melissa Paulsen, Abrar Fitwi, Masud Akbari

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In 2016, a U.S. business college was awarded a sub grant to work with FHI360, a nonprofit human development organization, to support a university in Afghanistan funded by the State Department’s U.S. Agency for International Development (USAID). A newly designed Master’s Degree in Finance and Accounting is being implemented to support Afghanistan’s goal of 20% females in higher education and industry by 2020 and to use finance and accounting international standards to attract capital investment for economic development. This paper will present a case study to describe the co-construction of an approach to an International Flipped Faculty Development Model grounded in blended learning theory. Like education in general, faculty development is also evolving from the traditional face to face environment and interactions to the fully online and now to a best of both blends. Flipped faculty development is both a means and a model for careful integration of the strengths of the synchronous and asynchronous dynamics and technologies with the combination of intentional sequencing to pre-online interactions that prepares and enhances the face to face faculty development and mentorship residencies with follow-up post-online support. Initial benefits from this model include giving the Afghan faculty an opportunity to experience and apply modern teaching and learning strategies with technology in their own classroom. Furthermore, beyond the technological and pedagogical affordances, the reciprocal benefits gained from the mentor-mentee, face-to-face relationship will be explored. Evidence to support this model includes: empirical findings from pre- and post-Faculty Mentor/ Mentee survey results, Faculty Mentorship group debriefs, Faculty Mentorship contact logs, and student early/end of semester feedback. In addition to presenting and evaluating this model, practical challenges and recommendations for replicating international flipped faculty development partnerships will be provided.

Keywords: educational development, faculty development, international development, flipped learning

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2739 Prediction of Pounding between Two SDOF Systems by Using Link Element Based On Mathematic Relations and Suggestion of New Equation for Impact Damping Ratio

Authors: Seyed M. Khatami, H. Naderpour, R. Vahdani, R. C. Barros

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Many previous studies have been carried out to calculate the impact force and the dissipated energy between two neighboring buildings during seismic excitation, when they collide with each other. Numerical studies are an important part of impact, which several researchers have tried to simulate the impact by using different formulas. Estimation of the impact force and the dissipated energy depends significantly on some parameters of impact. Mass of bodies, stiffness of spring, coefficient of restitution, damping ratio of dashpot and impact velocity are some known and unknown parameters to simulate the impact and measure dissipated energy during collision. Collision is usually shown by force-displacement hysteresis curve. The enclosed area of the hysteresis loop explains the dissipated energy during impact. In this paper, the effect of using different types of impact models is investigated in order to calculate the impact force. To increase the accuracy of impact model and to optimize the results of simulations, a new damping equation is assumed and is validated to get the best results of impact force and dissipated energy, which can show the accuracy of suggested equation of motion in comparison with other formulas. This relation is called "n-m". Based on mathematical relation, an initial value is selected for the mentioned coefficients and kinetic energy loss is calculated. After each simulation, kinetic energy loss and energy dissipation are compared with each other. If they are equal, selected parameters are true and, if not, the constant of parameters are modified and a new analysis is performed. Finally, two unknown parameters are suggested to estimate the impact force and calculate the dissipated energy.

Keywords: impact force, dissipated energy, kinetic energy loss, damping relation

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2738 Study of the Polymer Elastic Behavior in the Displacement Oil Drops at Pore Scale

Authors: Luis Prada, Jose Gomez, Arlex Chaves, Julio Pedraza

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Polymeric liquids have been used in the oil industry, especially at enhanced oil recovery (EOR). From the rheological point of view, polymers have the particularity of being viscoelastic liquids. One of the most common and useful models to describe that behavior is the Upper Convected Maxwell model (UCM). The main characteristic of the polymer used in EOR process is the increase in viscosity which pushes the oil outside of the reservoir. The elasticity could contribute in the drag of the oil that stays in the reservoir. Studying the elastic effect on the oil drop at the pore scale, bring an explanation if the addition of elastic force could mobilize the oil. This research explores if the contraction and expansion of the polymer in the pore scale may increase the elastic behavior of this kind of fluid. For that reason, this work simplified the pore geometry and build two simple geometries with micrometer lengths. Using source terms with the user define a function this work introduces the UCM model in the ANSYS fluent simulator with the purpose of evaluating the elastic effect of the polymer in a contraction and expansion geometry. Also, using the Eulerian multiphase model, this research considers the possibility that extra elastic force will show a deformation effect on the oil; for that reason, this work considers an oil drop on the upper wall of the geometry. Finally, all the simulations exhibit that at the pore scale conditions exist extra vortices at UCM model but is not possible to deform the oil completely and push it outside of the restrictions, also this research find the conditions for the oil displacement.

Keywords: ANSYS fluent, interfacial fluids mechanics, polymers, pore scale, viscoelasticity

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2737 Using 3-Glycidoxypropyltrimethoxysilane Functionalized SiO2 Nanoparticles to Improve Flexural Properties of Glass Fibers/Epoxy Grid-Stiffened Composite Panels

Authors: Reza Eslami-Farsani, Hamed Khosravi, Saba Fayazzadeh

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Lightweight and efficient structures have the aim to enhance the efficiency of the components in various industries. Toward this end, composites are one of the most widely used materials because of durability, high strength and modulus, and low weight. One type of the advanced composites is grid-stiffened composite (GSC) structures, which have been extensively considered in aerospace, automotive, and aircraft industries. They are one of the top candidates for replacing some of the traditional components, which are used here. Although there are a good number of published surveys on the design aspects and fabrication of GSC structures, little systematic work has been reported on their material modification to improve their properties, to our knowledge. Matrix modification using nanoparticles is an effective method to enhance the flexural properties of the fibrous composites. In the present study, a silane-coupling agent (3-glycidoxypropyltrimethoxysilane/3-GPTS) was introduced onto the silica (SiO2) nanoparticle surface and its effects on the three-point flexural response of isogrid E-glass/epoxy composites were assessed. Based on the fourier transform infrared spectrometer (FTIR) spectra, it was inferred that the 3-GPTS coupling agent was successfully grafted onto the surface of SiO2 nanoparticles after modification. Flexural test revealed an improvement of 16%, 14%, and 36% in stiffness, maximum load and energy absorption of the isogrid specimen filled with 3 wt.% 3-GPTS/SiO2 compared to the neat one. It would be worth mentioning that in these structures, considerable energy absorption was observed after the primary failure related to the load peak. In addition, 3-GPTMS functionalization had a positive effect on the flexural behavior of the multiscale isogrid composites. In conclusion, this study suggests that the addition of modified silica nanoparticles is a promising method to improve the flexural properties of the grid-stiffened fibrous composite structures.

Keywords: isogrid-stiffened composite panels, silica nanoparticles, surface modification, flexural properties

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2736 Examination of the Self-Expression Model with Reference to Luxury Watches with Particular Regard of the Buying-Reasons

Authors: Christopher Benedikt Jakob

Abstract:

Human beings are intrigued by luxury watches for decades. It is fascinating that customers pay an enormous amount of money for specific wristwatch models. It is fascinating that customers of the luxury watch industry accept a yearly price increase. This behavior increases their desirability even more. Luxury watches are perceived as status symbols, but they are additionally accepted as a currency without the disadvantage of currency fluctuations. It is obvious that the symbolic value is more important as the functional value with reference to the buying-reasons as regards luxury watches. Nowadays human beings do not need a wristwatch to read the time. Tablets, notebooks, smartphones, the watch in the car and watches on public places are used to inform people about the current time. This is one of the reasons why there is a trend that people do not wear wristwatches anymore. Due to these facts, this study has the intention to give answers to the question why people invest an enormous amount of money on the consumption of luxury watches and why those watches are seen as a status symbol. The study examines why the luxury watch industry records significant growth rates. The self-expression model is used as an appropriate methodology to find reasons why human beings purchase specific luxury watches. This evaluative approach further discusses if human beings are aware of their current self and their ideal self and how they express them. Furthermore, the research critically evaluates the people’s social self and their ideal social self. One of the goals is to identify if customers know why they like specific luxury watches and dislike others although they have the same quality and cost comparable prices.

Keywords: luxury watch, brand awareness, buying-behaviour, consumer, self-expression

Procedia PDF Downloads 155
2735 Gradient Boosted Trees on Spark Platform for Supervised Learning in Health Care Big Data

Authors: Gayathri Nagarajan, L. D. Dhinesh Babu

Abstract:

Health care is one of the prominent industries that generate voluminous data thereby finding the need of machine learning techniques with big data solutions for efficient processing and prediction. Missing data, incomplete data, real time streaming data, sensitive data, privacy, heterogeneity are few of the common challenges to be addressed for efficient processing and mining of health care data. In comparison with other applications, accuracy and fast processing are of higher importance for health care applications as they are related to the human life directly. Though there are many machine learning techniques and big data solutions used for efficient processing and prediction in health care data, different techniques and different frameworks are proved to be effective for different applications largely depending on the characteristics of the datasets. In this paper, we present a framework that uses ensemble machine learning technique gradient boosted trees for data classification in health care big data. The framework is built on Spark platform which is fast in comparison with other traditional frameworks. Unlike other works that focus on a single technique, our work presents a comparison of six different machine learning techniques along with gradient boosted trees on datasets of different characteristics. Five benchmark health care datasets are considered for experimentation, and the results of different machine learning techniques are discussed in comparison with gradient boosted trees. The metric chosen for comparison is misclassification error rate and the run time of the algorithms. The goal of this paper is to i) Compare the performance of gradient boosted trees with other machine learning techniques in Spark platform specifically for health care big data and ii) Discuss the results from the experiments conducted on datasets of different characteristics thereby drawing inference and conclusion. The experimental results show that the accuracy is largely dependent on the characteristics of the datasets for other machine learning techniques whereas gradient boosting trees yields reasonably stable results in terms of accuracy without largely depending on the dataset characteristics.

Keywords: big data analytics, ensemble machine learning, gradient boosted trees, Spark platform

Procedia PDF Downloads 232
2734 Organic Agriculture in Pakistan: Opportunities, Challenges, and Future Directions

Authors: Sher Ali

Abstract:

Organic agriculture has gained significant momentum globally as a sustainable and environmentally friendly farming practice. In Pakistan, amidst growing concerns about food security, environmental degradation, and health issues related to conventional farming methods, the adoption of organic agriculture presents a promising pathway for agricultural development. This abstract aims to provide an overview of the status, opportunities, challenges, and future directions of organic agriculture in Pakistan. It delves into the current state of organic farming practices, including the extent of adoption, key crops cultivated, and the regulatory framework governing organic certification. Furthermore, the abstract discusses the unique opportunities that Pakistan offers for organic agriculture, such as its diverse agro-climatic zones, rich biodiversity, and traditional farming knowledge. It highlights successful initiatives and case studies that showcase the potential of organic farming to improve rural livelihoods, enhance food security, and promote sustainable agricultural practices. However, the abstract also addresses the challenges hindering the widespread adoption of organic agriculture in Pakistan, ranging from limited awareness and technical know-how among farmers to inadequate infrastructure and market linkages. It emphasizes the need for supportive policies, capacity-building programs, and investment in research and extension services to overcome these challenges and promote the growth of the organic agriculture sector. Lastly, the abstract outlines future directions and recommendations for advancing organic agriculture in Pakistan, including strategies for scaling up production, strengthening certification mechanisms, and fostering collaboration among stakeholders. By shedding light on the opportunities, challenges, and potential of organic agriculture in Pakistan, this abstract aims to contribute to the discourse on sustainable farming practices at the upcoming Agro Conference in the USA. It invites participants to engage in dialogue, share experiences, and explore avenues for collaboration toward promoting organic agriculture for a healthier, more resilient food system.

Keywords: agriculture, challenges, organic, Pakistan

Procedia PDF Downloads 38
2733 The Influence of Coarse Aggregate Morphology on Concrete Workability: A Case Study with Algerian Crushed Limestone

Authors: Ahmed Boufedah Badissi, Ahmed Beroual, Farid Boursas

Abstract:

This research aims to elucidate the role of coarse aggregate in influencing the fresh properties of normal-strength concrete. Specifically, it is aimed to identify the optimal gradation of coarse aggregate to enhance workability. While existing literature discusses the impact of aggregate granularity on concrete workability, more numerical data or models need to quantify the relationship between workability, granularity, and coarse aggregate shape. The main objective is to create a model that describes how coarse aggregate morphology contributes to fresh concrete properties. To investigate the effect of coarse aggregate gradation on Normal Strength Concrete (NSC) workability, various combinations of coarse aggregates (4/22.4 mm) were produced in the laboratory, utilizing three elementary classes: finer coarse aggregate 4/8 mm (Fca), medium coarse aggregate 8/16 mm (Mca), and coarser coarse aggregate 16/22.4 mm (Cca). We introduced a factor, FCR (Finer to Coarser coarse aggregate Ratio), as a numerical parameter to provide a quantitative evaluation and more detailed results analysis. Quantitative characterization parameters for coarse aggregate morphology were established, exploring the influence of particle size distribution, specific surface, and aggregate shape on workability. The research findings are significant for establishing correlations between coarse aggregate morphology and concrete properties. FCR emerges as a valuable tool for predicting the impact of aggregate gradation variations on concrete. The results of this study create a valuable database for construction professionals and concrete producers, affirming that the fresh properties of NSC are intricately linked to coarse aggregate morphology, particularly gradation.

Keywords: morphology, coarse aggregate, workability, fresh properties, gradation

Procedia PDF Downloads 53
2732 Cadaveric Dissection versus Systems-Based Anatomy: Testing Final Year Student Surface Anatomy Knowledge to Compare the Long-Term Effectiveness of Different Course Structures

Authors: L. Sun, T. Hargreaves, Z. Ahmad

Abstract:

Newly-qualified Foundation Year 1 doctors in the United Kingdom are frequently expected to perform practical skills involving the upper limb in clinical practice (for example, venipuncture, cannulation, and blood gas sampling). However, a move towards systems-based undergraduate medical education in the United Kingdom often precludes or limits dedicated time to anatomy teaching with cadavers or prosections, favouring only applied anatomy in the context of pathology. The authors hypothesised that detailed anatomical knowledge may consequently be adversely affected, particularly with respect to long-term retention. A simple picture quiz and accompanying questionnaire testing the identification of 7 upper limb surface landmarks was distributed to a total of 98 final year medical students from two universities - one with a systems-based curriculum, and one with a dedicated longitudinal dissection-based anatomy module in the first year of study. Students with access to dissection and prosection-based anatomy teaching performed more strongly, with a significantly higher rate of correct identification of all but one of the landmarks. Furthermore, it was notable that none of the students who had previously undertaken a systems-based course scored full marks, compared with 20% of those who had participated in the more dedicated anatomy course. This data suggests that a traditional, dissection-based approach to undergraduate anatomy teaching is superior to modern system-based curricula, in terms of aiding long-term retention of anatomical knowledge pertinent to newly-qualified doctors. The authors express concern that this deficit in proficiency could be detrimental to patient care in clinical practice, and propose that, where dissection-led anatomy teaching is not available, further anatomy revision modules are implemented throughout undergraduate education to aid knowledge retention and support clinical excellence.

Keywords: dissection, education, surface anatomy, upper limb

Procedia PDF Downloads 124
2731 Performance and Nutritional Evaluation of Moringa Leaves Dried in a Solar-Assisted Heat Pump Dryer Integrated with Thermal Energy Storage

Authors: Aldé Belgard Tchicaya Loemba, Baraka Kichonge, Thomas Kivevele, Juma Rajabu Selemani

Abstract:

Plants used for medicinal purposes are extremely perishable, owing to moisture-enhanced enzymatic and microorganism activity, climate change, and improper handling and storage. Experiments have shown that drying the medicinal plant without affecting the active nutrients and controlling the moisture content as much as possible can extend its shelf life. Different traditional and modern drying techniques for preserving medicinal plants have been developed, with some still being improved in Sub-Saharan Africa. However, many of these methods fail to address the most common issues encountered when drying medicinal plants, such as nutrient loss, long drying times, and a limited capacity to dry during the evening or cloudy hours. Heat pump drying is an alternate drying method that results in no nutritional loss. Furthermore, combining a heat pump dryer with a solar energy storage system appears to be a viable option for all-weather drying without affecting the nutritional values of dried products. In this study, a solar-assisted heat pump dryer integrated with thermal energy storage is developed for drying moringa leaves. The study also discusses the performance analysis of the developed dryer as well as the proximate analysis of the dried moringa leaves. All experiments were conducted from 11 a.m. to 4 p.m. to assess the dryer's performance in “daytime mode”. Experiment results show that the drying time was significantly reduced, and the dryer demonstrated high performance in preserving all of the nutrients. In 5 hours of the drying process, the moisture content was reduced from 75.7 to 3.3%. The average COP value was 3.36, confirming the dryer's low energy consumption. The findings also revealed that after drying, the content of protein, carbohydrates, fats, fiber, and ash greatly increased.

Keywords: heat pump dryer, efficiency, moringa leaves, proximate analysis

Procedia PDF Downloads 76
2730 Phenolic Composition and Antioxidant Activity of Sorbus L. Fruits and Leaves

Authors: Raudone Lina, Raudonis Raimondas, Gaivelyte Kristina, Pukalskas Audrius, Janulis Valdimaras, Viskelis Pranas

Abstract:

Sorbus L. species are widely distributed in the Northern hemisphere and have been used for medicinal purposes in various traditional medicine systems and as food ingredients. Various Sorbus L. raw materials, fruits, leaves, inflorescences, barks, possess diuretic, anti-inflammatory, hypoglycemic, anti-diarrheal and vasoprotective activities. Phenolics, to whom main pharmacological activities are attributed, are compounds of interest due to their notable antioxidant activity. The aim of this study was to determine the antioxidant profiles of fruits and leaves of selected Sorbus L. species (S. anglica, S. aria f. latifolia, S. arranensis, S. aucuparia, S. austriaca, S. caucasica, S. commixta, S. discolor, S. gracilis, S. hostii, S. semi-incisa, S. tianschanica) and to identify the phenolic compounds with potent contribution to antioxidant activity. Twenty two constituents were identified in Sorbus L. species using ultra high performance liquid chromatography coupled to quadruple and time-of-flight mass spectrometers (UPLC–QTOF–MS). Reducing activity of individual constituents was determined using high performance liquid chromatography (HPLC) coupled to post-column FRAP assay. Signicantly greatest trolox equivalent values corresponding up to 45% of contribution to antioxidant activity were assessed for neochlorogenic and chlorogenic acids, which were determined as markers of antioxidant activity in samples of leaves and fruits. Characteristic patterns of antioxidant profiles obtained using HPLC post-column FRAP assay significantly depend on specific Sorbus L. species and raw materials and are suitable for equivalency research of Sorbus L. fruits and leaves. Selecting species and target plant organs with richest phenolic composition and strongly expressed antioxidant power is the first step in further research of standardized extracts.

Keywords: FRAP, antioxidant, phenolic, Sorbus L., chlorogenic acid, neochlorogenic acid

Procedia PDF Downloads 446
2729 Efficient Human Motion Detection Feature Set by Using Local Phase Quantization Method

Authors: Arwa Alzughaibi

Abstract:

Human Motion detection is a challenging task due to a number of factors including variable appearance, posture and a wide range of illumination conditions and background. So, the first need of such a model is a reliable feature set that can discriminate between a human and a non-human form with a fair amount of confidence even under difficult conditions. By having richer representations, the classification task becomes easier and improved results can be achieved. The Aim of this paper is to investigate the reliable and accurate human motion detection models that are able to detect the human motions accurately under varying illumination levels and backgrounds. Different sets of features are tried and tested including Histogram of Oriented Gradients (HOG), Deformable Parts Model (DPM), Local Decorrelated Channel Feature (LDCF) and Aggregate Channel Feature (ACF). However, we propose an efficient and reliable human motion detection approach by combining Histogram of oriented gradients (HOG) and local phase quantization (LPQ) as the feature set, and implementing search pruning algorithm based on optical flow to reduce the number of false positive. Experimental results show the effectiveness of combining local phase quantization descriptor and the histogram of gradient to perform perfectly well for a large range of illumination conditions and backgrounds than the state-of-the-art human detectors. Areaunder th ROC Curve (AUC) of the proposed method achieved 0.781 for UCF dataset and 0.826 for CDW dataset which indicates that it performs comparably better than HOG, DPM, LDCF and ACF methods.

Keywords: human motion detection, histograms of oriented gradient, local phase quantization, local phase quantization

Procedia PDF Downloads 250
2728 HIV/AIDS Knowledge and Social Integration among Street Children: A Systematic Review

Authors: Dewi Indah Irianti

Abstract:

Introduction: Street children include one of the populations at risk of HIV infection. Their vulnerability to these situations is increased by their lack of understanding of the changes associated with adolescence, the lack of knowledge and skills which could help them to make healthy choices. Social integration increased AIDS knowledge among migrant workers in Thailand. Although social integration has been incorporated into health research in other areas, it has received less attention in AIDS prevention research. This factor has not been integrated into models for HIV prevention. Objectives: The goal of this review is to summarize available knowledge about factors related to HIV/AIDS knowledge and to examine whether social integration was reviewed among street children. Methodology: This study performed a systematic search for English language articles published between January 2006 and March 2016 using the following keywords in various combination: street children, HIV/AIDS knowledge and social integration from the following bibliographic databases: Scopus, ProQuest, JSTOR, ScienceDirect, SpringerLink, EBSCOhost, Sage Publication, Clinical Key, Google Web, and Google Scholar . Results: A total of 10 articles met the inclusion criteria were systematically reviewed. This study reviews the existing quantitative and qualitative literature regarding the HIV/AIDS knowledge of street children in many countries. The study locations were Asia, the Americas, Europe, and Africa. The most determinants associated with HIV/AIDS knowledge among street children are age and sex. In this review, social integration that may be associated with HIV/AIDS knowledge among street children has not been investigated. Conclusion: To the best of the author’s knowledge, this study found that there is no research examining the relationship of social integration with the HIV knowledge among street children. This information may assist in the development of relevant strategies and HIV prevention programs to improve HIV knowledge and decrease risk behaviors among street children.

Keywords: HIV/AIDS knowledge, review, social integration, street children

Procedia PDF Downloads 311
2727 Double Row Taper Roller Bearing Wheel-end System in Rigid Rear Drive Axle in Heavy Duty SUV Passenger Vehicle

Authors: Mohd Imtiaz S, Saurabh Jain, Pothiraj K.

Abstract:

In today’s highly competitive passenger vehicle market, comfortable driving experience is one of the key parameters significantly weighed by the customer. Smooth ride and handling of the vehicle with exceptionally reliable wheel end solution is a paramount requirement in passenger Sports Utility Vehicle (SUV) vehicles subjected to challenging terrains and loads with rigid rear drive axle configuration. Traditional wheel-end bearing systems in passenger segment rigid rear drive axle utilizes the semi-floating layout, which imparts vertical bending loads and torsion to the axle shafts. The wheel-end bearing is usually a Single or Double Row Deep-Groove Ball Bearing (DRDGBB) or Double Row Angular Contact Ball Bearing (DRACBB). This solution is cost effective and simple in architecture. However, it lacks effectiveness against the heavy loads subjected to a SUV vehicle, especially the axial trust at high-speed cornering. This paper describes the solution of Double Row Taper Roller Bearing (DRTRB) wheel-end for a SUV vehicle in the rigid rear drive axle and improvement in terms of maximizing its load carrying capacity along with better reliability in terms of axial thrust in high-speed cornering. It describes the advantage of geometry of DRTRB over DRDGBB and DRACBB highlighting contact and load flow. The paper also highlights the vehicle level considerations affecting the B10 life of the bearing system for better selection of the DRTRB wheel-ends systems. This paper also describes real time vehicle level results along with theoretical improvements.

Keywords: axial thrust, b10 life, deep-groove ball bearing, taper roller bearing, semi-floating layout.

Procedia PDF Downloads 67
2726 Multi-Point Dieless Forming Product Defect Reduction Using Reliability-Based Robust Process Optimization

Authors: Misganaw Abebe Baye, Ji-Woo Park, Beom-Soo Kang

Abstract:

The product quality of multi-point dieless forming (MDF) is identified to be dependent on the process parameters. Moreover, a certain variation of friction and material properties may have a substantially worse influence on the final product quality. This study proposed on how to compensate the MDF product defects by minimizing the sensitivity of noise parameter variations. This can be attained by reliability-based robust optimization (RRO) technique to obtain the optimal process setting of the controllable parameters. Initially two MDF Finite Element (FE) simulations of AA3003-H14 saddle shape showed a substantial amount of dimpling, wrinkling, and shape error. FE analyses are consequently applied on ABAQUS commercial software to obtain the correlation between the control process setting and noise variation with regard to the product defects. The best prediction models are chosen from the family of metamodels to swap the computational expensive FE simulation. Genetic algorithm (GA) is applied to determine the optimal process settings of the control parameters. Monte Carlo Analysis (MCA) is executed to determine how the noise parameter variation affects the final product quality. Finally, the RRO FE simulation and the experimental result show that the amendment of the control parameters in the final forming process leads to a considerably better-quality product.

Keywords: dimpling, multi-point dieless forming, reliability-based robust optimization, shape error, variation, wrinkling

Procedia PDF Downloads 241
2725 A Transient Coupled Numerical Analysis of the Flow of Magnetorheological Fluids in Closed Domains

Authors: Wael Elsaady, S. Olutunde Oyadiji, Adel Nasser

Abstract:

The non-linear flow characteristics of magnetorheological (MR) fluids in MR dampers are studied via a coupled numerical approach that incorporates a two-phase flow model. The approach couples the Finite Element (FE) modelling of the damper magnetic circuit, with the Computational Fluid Dynamics (CFD) analysis of the flow field in the damper. The two-phase flow CFD model accounts for the effect of fluid compressibility due to the presence of liquid and gas in the closed domain of the damper. The dynamic mesh model included in ANSYS/Fluent CFD solver is used to simulate the movement of the MR damper piston in order to perform the fluid excitation. The two-phase flow analysis is studied by both Volume-Of-Fluid (VOF) model and mixture model that are included in ANSYS/Fluent. The CFD models show that the hysteretic behaviour of MR dampers is due to the effect of fluid compressibility. The flow field shows the distributions of pressure, velocity, and viscosity contours. In particular, it shows the high non-Newtonian viscosity in the affected fluid regions by the magnetic field and the low Newtonian viscosity elsewhere. Moreover, the dependence of gas volume fraction on the liquid pressure inside the damper is predicted by the mixture model. The presented approach targets a better understanding of the complicated flow characteristics of viscoplastic fluids that could be applied in different applications.

Keywords: viscoplastic fluid, magnetic FE analysis, computational fluid dynamics, two-phase flow, dynamic mesh, user-defined functions

Procedia PDF Downloads 170