Search results for: in vitro study
19557 The Effects of the Aspect Ratio of a Flexible Cylinder on the Vortex Dynamics
Authors: Abouzar Kaboudian, Ravi Chaithanya Mysa, Boo Cheong Khoo, Rajeev Kumar Jaiman
Abstract:
The vortex structures observed in the wake of a flexible cylinder can be significantly different from those of a traditional vibrating, spring mounted, rigid cylinder. These differences can significantly affect the VIV characteristics of the flow and subsequently the VIV response of the cylindrical structures. In this work, we present how the aspect ratio of a flexible cylinder can change the vortex structures in its wake. We will discuss different vortex dynamics which can be observed in the wake of the vibrating flexible cylinder, and how they can affect the vibrational response of the cylinder. Moreover, we will study the transition of these structures versus the aspect ratio of the flexible cylinder. We will discuss how these transitions affect the in-line and transverse forces on the structure. In the end, we will provide general guidelines on the minimum acceptable aspect ratio for the offshore riser studies which may have grave implications for future numerical and experimental works.Keywords: aspect ratio, flexible cylinder, vortex-shedding, VIV
Procedia PDF Downloads 48119556 Settlement Performance of Granular Column Reinforced Soil
Authors: Muneerah Jeludin
Abstract:
The vibrated column has been widely used over the last three decades to improve the performance of soft ground and engineered compacted fill. The main reason for adopting this technique is that it is economically viable and environmental friendly. The performance of granular column with regards to bearing capacity has been well documented; however, information regarding the settlement behavior of granular columns is still limited. This paper aims to address the findings from a laboratory model study in terms of its settlement improvement. A 300 mm diameter and 400 mm high kaolin clay model was used in this investigation. Columns of various heights were installed in the clay bed using replacement method. The results in relation to load sharing mechanism between the column and surrounding clay just under the footing indicated that in short column, the available shaft resistance was not significant and introduces a potential for end braing failure as opposed to bulging failure in long columns. The settlement improvement factor corroborates well with field observations.Keywords: ground improvement, model test, reinforced soil, foundation
Procedia PDF Downloads 25819555 Experimental Investigation of Energy Performance of Split Type Air Conditioning for Building under Various Indoor Set Point Temperatures and Different Air Flowrates through Cooling Coil
Authors: Niran Watchrodom
Abstract:
An experimental study was carried out to investigate the energy performance of a 1.5 Tr commercial split type air conditioner operating at different indoor set points and different air flowrate circulating through the cooling coil. The refrigerant R-22 was used as working fluid. In this paper, the test conditions considered were varied as follows: The room temperature varied from 23, 24, 25, 26, and 27 C, the air velocity passing through the evaporator was varied from 1.9, 2.1 and 2.4 m/s. The air velocity passing through the condenser was kept constant at 5 m/s. The results showed that when the indoor temperature was high, 27 C, and air velocity was 1.9 m/s, the coefficient of performance (COP) of the system was 3.74. The electrical power consumption of compressor was 1.64 kW, the rate of heat transfer in the condenser and evaporator were 7.79 and 6.10 kW, respectively. The amount corresponding amount of condensed water coming out of evaporator was 8.20 liter. The system can applied to commercial building.Keywords: condensed water, coefficient of performance, air velocity
Procedia PDF Downloads 43119554 Body Image Dissatisfaction of Females: A Holistic Therapeutic Approach
Authors: Katy Eleanor Addinall
Abstract:
Women’s body image dissatisfaction is a widespread problem, and it is present in all age groups, on every socioeconomic level, in all occupations, all cultures, and religions. Body image dissatisfaction is a broad term that is used to vary from normal discontent of a woman about one or more of her physical attributes to extreme negative causes, for example, an eating disorder. South African women were examined, and an empirical qualitative study was done to evaluate the women’s thoughts and feelings regarding their bodies. The causes and effects of body image dissatisfaction were examined, and social science literature was used to determine the etiology of body image dissatisfaction, which confirmed that it is multifactorial. A variety of therapeutic aids were studied, and cognitive behavioural therapy appeared to be the most effective. Every woman is an individual with an individual body image and must be approached as an individual holistic being. Thus, a holistic pragmatic model was developed as a possible aid in the woman’s healing process.Keywords: body, body image, females, woman, therapy, dissatisfaction, holistic, cognitive behavioural therapy
Procedia PDF Downloads 13019553 The World of Great Wines: The Douro Valley Experience
Authors: A. Oliveira-Brochado, R. Silva, C. Paulino
Abstract:
The aim of this paper is to use an experiential view of wine tourism to develop a battery of items that can potentially capture the overall Douro Valley experience from the tourist’s perspective. The Douro Valley, a UNESCO World Heritage region located in Portugal, was the target of this study. The research took a mixed approach using both qualitative and quantitative designs. Firstly, we combine the literature review on service quality scales with a content analysis of five in-depth interviews with winery managers and a focus group with wine tourists to identify the main dimensions of the overall tourism experience and to develop a battery of items for each dimension. Eight dimensions of the overall wine tourism experience came out, as follows: winery service and staff, winery facilities, winery service, wine product, wine region environment, wine region accessibilities, wine region´s offerings, and the wine region and winery reputation.Keywords: wine tourism, Douro region, survey, wineries, experience
Procedia PDF Downloads 28519552 South Korean Discourse on Bioecomomy in the Sector of Agriculture
Authors: Mi Sun Park
Abstract:
Biotechnology provides us with technological solutions to resource-based challenges facing the global society. A bioeconomy or bio-based economy emerged as all economic activities derived from biotechnology. This paper aims to understand discourses on bioeconomy in the sector of agriculture with three dimensions; media discourse, science discourse, and policy discourse. For achieving research goals, content analysis was applied to this research. Media articles, academic journal articles and policy documents published from 2000 to 2016 were collected in South Korea. The text was coded and analyzed with the categories of speakers and their arguments. The research findings indicate that powerful actors and key messages of bioeconomy in South Korean agriculture. Differences and similarities among media, science, and policy were examined. Therefore this case study can contribute to understanding dynamic interaction and interfaces of media, science and policy discourse on biotechnology in the sector of agriculture.Keywords: media, discourse, bioeconomy, agriculture
Procedia PDF Downloads 22619551 Research on Residential Block Fabric: A Case Study of Hangzhou West Area
Abstract:
Residential block construction of big cities in China began in the 1950s, and four models had far-reaching influence on modern residential block in its development process, including unit compound and residential district in 1950s to 1980s, and gated community and open community in 1990s to now. Based on analysis of the four models’ fabric, the article takes residential blocks in Hangzhou west area as an example and carries on the studies from urban structure level and block special level, mainly including urban road network, land use, community function, road organization, public space and building fabric. At last, the article puts forward semi-open sub-community strategy to improve the current fabric.Keywords: Hangzhou west area, residential block model, residential block fabric, semi-open sub-community strategy
Procedia PDF Downloads 41019550 Experimental Investigation of R600a as a Retrofit for R134a in a Household Refrigerator
Authors: T. O Babarinde, F. A Oyawale, O. S Ohunakin, R. O Ohunakin, R. O Leramo D.S Adelekan
Abstract:
This paper presents an experimental study of R600a, environment-friendly refrigerants with low global warming potential (GWP), zero ozone depletion potential (ODP), as a substitute for R134a in domestic refrigerator. A refrigerator designed to work with R134a was used for this experiment, the capillary for this experiment was not varied at anytime during the experiment. 40, 60, 80g, charge of R600a were tested against 100 g of R134a under the designed capillary length of the refrigerator, and the performance using R600a was evaluated and compared with its performance when R134a was used. The results obtained showed that the design temperature and pull-down time set by International Standard Organisation (ISO) for small refrigerator was achieved using both 80g of R600a and 100g of R134a but R134a has earlier pulled down time than using R600a. The average coefficient of performance (COP) obtained using R600a is 17.7% higher than that of R134a while the average power consumption is 42.5 % lower than R134a, which shows that R600a can be used as replacement for R134a in domestic refrigerator without necessarily need to modified the capillary.Keywords: domestic refrigerator, experimental, R600a, R134a
Procedia PDF Downloads 51219549 Improved Artificial Bee Colony Algorithm for Non-Convex Economic Power Dispatch Problem
Authors: Badr M. Alshammari, T. Guesmi
Abstract:
This study presents a modified version of the artificial bee colony (ABC) algorithm by including a local search technique for solving the non-convex economic power dispatch problem. The local search step is incorporated at the end of each iteration. Total system losses, valve-point loading effects and prohibited operating zones have been incorporated in the problem formulation. Thus, the problem becomes highly nonlinear and with discontinuous objective function. The proposed technique is validated using an IEEE benchmark system with ten thermal units. Simulation results demonstrate that the proposed optimization algorithm has better convergence characteristics in comparison with the original ABC algorithm.Keywords: economic power dispatch, artificial bee colony, valve-point loading effects, prohibited operating zones
Procedia PDF Downloads 24919548 Study of a Photovoltaic System Using MPPT Buck-Boost Converter
Authors: A. Bouchakour, L. Zaghba, M. Brahami, A. Borni
Abstract:
The work presented in this paper present the design and the simulation of a centrifugal pump coupled to a photovoltaic (PV) generator via a MPPT controller. The PV system operating is just done in sunny period by using water storage instead of electric energy storage. The process concerns the modelling, identification and simulation of a photovoltaic pumping system, the centrifugal pump is driven by an asynchronous three-phase voltage inverter sine triangle PWM motor through. Two configurations were simulated. For the first, it is about the alimentation of the motor pump group from electrical power supply. For the second, the pump unit is connected directly to the photovoltaic panels by integration of a MPPT control. A code of simulation of the solar pumping system was initiated under the Matlab-Simulink environment. Very convivial and flexible graphic interfaces allow an easy use of the code and knowledge of the effects of change of the sunning and temperature on the pumping system.Keywords: photovoltaic generator, chopper, electrical motor, centrifugal pump
Procedia PDF Downloads 36819547 Integrative-Cyclical Approach to the Study of Quality Control of Resource Saving by the Use of Innovation Factors
Authors: Anatoliy A. Alabugin, Nikolay K. Topuzov, Sergei V. Aliukov
Abstract:
It is well known, that while we do a quantitative evaluation of the quality control of some economic processes (in particular, resource saving) with help innovation factors, there are three groups of problems: high uncertainty of indicators of the quality management, their considerable ambiguity, and high costs to provide a large-scale research. These problems are defined by the use of contradictory objectives of enhancing of the quality control in accordance with innovation factors and preservation of economic stability of the enterprise. The most acutely, such factors are felt in the countries lagging behind developed economies of the world according to criteria of innovativeness and effectiveness of management of the resource saving. In our opinion, the following two methods for reconciling of the above-mentioned objectives and reducing of conflictness of the problems are to solve this task most effectively: 1) the use of paradigms and concepts of evolutionary improvement of quality of resource-saving management in the cycle "from the project of an innovative product (technology) - to its commercialization and update parameters of customer value"; 2) the application of the so-called integrative-cyclical approach which consistent with complexity and type of the concept, to studies allowing to get quantitative assessment of the stages of achieving of the consistency of these objectives (from baseline of imbalance, their compromise to achievement of positive synergies). For implementation, the following mathematical tools are included in the integrative-cyclical approach: index-factor analysis (to identify the most relevant factors); regression analysis of relationship between the quality control and the factors; the use of results of the analysis in the model of fuzzy sets (to adjust the feature space); method of non-parametric statistics (for a decision on the completion or repetition of the cycle in the approach in depending on the focus and the closeness of the connection of indicator ranks of disbalance of purposes). The repetition is performed after partial substitution of technical and technological factors ("hard") by management factors ("soft") in accordance with our proposed methodology. Testing of the proposed approach has shown that in comparison with the world practice there are opportunities to improve the quality of resource-saving management using innovation factors. We believe that the implementation of this promising research, to provide consistent management decisions for reducing the severity of the above-mentioned contradictions and increasing the validity of the choice of resource-development strategies in terms of parameters of quality management and sustainability of enterprise, is perspective. Our existing experience in the field of quality resource-saving management and the achieved level of scientific competence of the authors allow us to hope that the use of the integrative-cyclical approach to the study and evaluation of the resulting and factor indicators will help raise the level of resource-saving characteristics up to the value existing in the developed economies of post-industrial type.Keywords: integrative-cyclical approach, quality control, evaluation, innovation factors. economic sustainability, innovation cycle of management, disbalance of goals of development
Procedia PDF Downloads 23419546 Teaching English as a Foreign Language: Insights from the Philippine Context
Authors: Arlene Villarama, Micol Grace Guanzon, Zenaida Ramos
Abstract:
This paper provides insights into teaching English as a Foreign Language in the Philippines. The authors reviewed relevant theories and literature, and provide an analysis of the issues in teaching English in the Philippine setting in the light of these theories. The authors made an investigation in Bagong Barrio National High School (BBNHS) - a public school in Caloocan City. The institution has a population of nearly 3,000 students. The performances of randomly chosen 365 respondents were scrutinised. The study regarding the success of teaching English as a foreign language to Filipino children were highlighted. This includes the respondents’ family background, surroundings, way of living, and their behavior and understanding regarding education. The results show that there is a significant relationship between demonstrative, communal, and logical areas that touch the efficacy of introducing English as a foreign Dialectal. Filipino children, by nature, are adventurous and naturally joyful even for little things. They are born with natural skills and capabilities to discover new things. They highly consider activities and work that ignite their curiosity. They love to be recognised and are inspired the most when given the assurance of acceptance and belongingness. Fun is the appealing influence to ignite and motivate learning. The magic word is excitement. The study reveals the many facets of the accumulation and transmission of erudition, in introduction and administration of English as a foreign phonological; it runs and passes through different channels of diffusion. Along the way, there are particles that act as obstructions in protocols where knowledge are to be gathered. Data gained from the respondents conceals a reality that is beyond one’s imagination. One significant factor that touches the inefficacy of understanding and using English as a foreign language is an erroneous outset gained from an old belief handed down from generation to generation. This accepted perception about the power and influence of the use of language, gives the novices either a negative or a positive notion. The investigation shows that a higher number of dislikes in the use of English can be tracked down from the belief of the story on how the English language came into existence. The belief that only the great and the influential have the right to use English as a means of communication kills the joy of acceptance. A significant notation has to be examined so as to provide a solution or if not eradicate the misconceptions that lie behind the substance of the matter. The result of the authors’ research depicts a substantial correlation between the emotional (demonstrative), social (communal), and intellectual (logical). The focus of this paper is to bring out the right notation and disclose the misconceptions with regards to teaching English as a foreign language. This will concentrate on the emotional, social, and intellectual areas of the Filipino learners and how these areas affect the transmittance and accumulation of learning. The authors’ aim is to formulate logical ways and techniques that would open up new beginnings in understanding and acceptance of the subject matter.Keywords: accumulation, behaviour, facets, misconceptions, transmittance
Procedia PDF Downloads 19119545 Indeterminacy: An Urban Design Tool to Measure Resilience to Climate Change, a Caribbean Case Study
Authors: Tapan Kumar Dhar
Abstract:
How well are our city forms designed to adapt to climate change and its resulting uncertainty? What urban design tools can be used to measure and improve resilience to climate change, and how would they do so? In addressing these questions, this paper considers indeterminacy, a concept originated in the resilience literature, to measure the resilience of built environments. In the realm of urban design, ‘indeterminacy’ can be referred to as built-in design capabilities of an urban system to serve different purposes which are not necessarily predetermined. An urban system, particularly that with a higher degree of indeterminacy, can enable the system to be reorganized and changed to accommodate new or unknown functions while coping with uncertainty over time. Underlying principles of this concept have long been discussed in the urban design and planning literature, including open architecture, landscape urbanism, and flexible housing. This paper argues that the concept indeterminacy holds the potential to reduce the impacts of climate change incrementally and proactively. With regard to sustainable development, both planning and climate change literature highly recommend proactive adaptation as it involves less cost, efforts, and energy than last-minute emergency or reactive actions. Nevertheless, the concept still remains isolated from resilience and climate change adaptation discourses even though the discourses advocate the incremental transformation of a system to cope with climatic uncertainty. This paper considers indeterminacy, as an urban design tool, to measure and increase resilience (and adaptive capacity) of Long Bay’s coastal settlements in Negril, Jamaica. Negril is one of the popular tourism destinations in the Caribbean highly vulnerable to sea-level rise and its associated impacts. This paper employs empirical information obtained from direct observation and informal interviews with local people. While testing the tool, this paper deploys an urban morphology study, which includes land use patterns and the physical characteristics of urban form, including street networks, block patterns, and building footprints. The results reveal that most resorts in Long Bay are designed for pre-determined purposes and offer a little potential to use differently if needed. Additionally, Negril’s street networks are found to be rigid and have limited accessibility to different points of interest. This rigidity can expose the entire infrastructure further to extreme climatic events and also impedes recovery actions after a disaster. However, Long Bay still has room for future resilient developments in other relatively less vulnerable areas. In adapting to climate change, indeterminacy can be reached through design that achieves a balance between the degree of vulnerability and the degree of indeterminacy: the more vulnerable a place is, the more indeterminacy is useful. This paper concludes with a set of urban design typologies to increase the resilience of coastal settlements.Keywords: climate change adaptation, resilience, sea-level rise, urban form
Procedia PDF Downloads 35719544 Tribological Behavior of EP Additives with Different Percentage of Sulfur
Authors: Salete Martins Alves, José Josemar de Oliveira Junior
Abstract:
The current efforts on design of lubricants are based in attending the new requirement of modern equipment with the focus on the choice of base oil and additives. Nowadays, there are different types of lubricant oils’ bases, such as mineral oils, synthetic oils, re-refined oils and vegetable oils. The lubrication in the boundary condition is controlled mainly by EP additives that interact with the surface forming very thin films. Therefore, the study’s goal is to evaluate the action of three EP additives, with different percentage of sulfur, on friction and wear reduction. They were evaluated in mineral and synthetic oils. Lubricants were prepared with synthetic and mineral oils and added 3 % and 5 % of EP additives. The friction and wear characteristics were studied using HFRR test. In this test, a normal load of 10 N was applied at a frequency of 20 Hz. The analysis of results has appointed that the percentage of sulfur in mineral oil has influenced on wear reduction. However, synthetic oil had good performance with low sulfur content.Keywords: boundary lubrication, EP additives, sulfur, wear
Procedia PDF Downloads 39519543 Compliance and Assessment Process of Information Technology in Accounting, in Turkey
Authors: Kocakaya Eda, Argun Doğan
Abstract:
This study analyzed the present state of information technology in the field of accounting by bibliometric analysis of scientific studies on the impact on the transformation of e-billing and tax managementin Turkey. With comparative bibliometric analysis, the innovation and positive effects of the process that changed with e-transformation in the field of accounting with e-transformation in businesses and the information technologies used in accounting and tax management were analyzed comparatively. By evaluating the data obtained as a result of these analyzes, suggestions on the use of information technologies in accounting and tax management and the positive and negative effects of e-transformation on the analyzed activities of the enterprises were emphasized. With the e-transformation, which will be realized with the most efficient use of information technologies in Turkey. The synergy and efficiency of IT technology developments in avcoounting and finance should be revealed in the light of scientific data, from the smallest business to the largest economic enterprises.Keywords: information technologies, E-invoice, E-Tax management, E-transformation, accounting programs
Procedia PDF Downloads 11219542 Event Extraction, Analysis, and Event Linking
Authors: Anam Alam, Rahim Jamaluddin Kanji
Abstract:
With the rapid growth of event in everywhere, event extraction has now become an important matter to retrieve the information from the unstructured data. One of the challenging problems is to extract the event from it. An event is an observable occurrence of interaction among entities. The paper investigates the effectiveness of event extraction capabilities of three software tools that are Wandora, Nitro and SPSS. We performed standard text mining techniques of these tools on the data sets of (i) Afghan War Diaries (AWD collection), (ii) MUC4 and (iii) WebKB. Information retrieval measures such as precision and recall which are computed under extensive set of experiments for Event Extraction. The experimental study analyzes the difference between events extracted by the software and human. This approach helps to construct an algorithm that will be applied for different machine learning methods.Keywords: event extraction, Wandora, nitro, SPSS, event analysis, extraction method, AFG, Afghan War Diaries, MUC4, 4 universities, dataset, algorithm, precision, recall, evaluation
Procedia PDF Downloads 58219541 Authentic Leadership, Task Performance, and Organizational Citizenship Behavior
Authors: C. V. Chen, Y. H. Jeng, S. J. Wang
Abstract:
Leadership is essential to enhancing followers’ psychological empowerment and has an effect on their willingness to take on extra-role behavior and aim for greater performance. Authentic leadership is confirmed to promote employees’ positive affect, psychological empowerment, well-being, and performance. Employees’ spontaneous undertaking of organizationally desired behaviors allows organizations’ gaining the edge in the fiercely competitive business environment. Apart from the contextual factor of leadership, individuals’ goal orientation is found to be highly related to his/her performance. To better understand the psychological process and potential moderation of personal goal orientation, this study investigates the effect of authentic leadership on employees’ task performance and organizational citizenship behavior by including psychological empowerment as the mediating factor and goal orientation as the moderating factor.Keywords: authentic leadership, task performance, organizational citizenship behavior, goal orientation
Procedia PDF Downloads 78719540 Experimental Investigation on the Behavior of Steel Fibers Reinforced Concrete under Impact Loading
Authors: Feng Fu, Ahmad Bazgir
Abstract:
This study aimed to investigate and examine the structural behaviour of steel fibre reinforced concrete slabs when subjected to impact loading using drop weight method. A number of compressive tests, tensile splitting tests, as well as impact tests were conducted. The experimental work consists of testing both conventional reinforced slabs and SFRC slabs. Parameters to be considered for carrying out the test will consist of the volume fraction of steel fibre, type of steel fibres, drop weight height and number of blows. Energy absorption of slabs under impact loading and failure modes were examined in-depth and compared with conventional reinforced concrete slab are investigated.Keywords: steel fibre reinforce concrete, compressive test, tensile splitting test, impact test
Procedia PDF Downloads 41319539 Gaussian Particle Flow Bernoulli Filter for Single Target Tracking
Authors: Hyeongbok Kim, Lingling Zhao, Xiaohong Su, Junjie Wang
Abstract:
The Bernoulli filter is a precise Bayesian filter for single target tracking based on the random finite set theory. The standard Bernoulli filter often underestimates the number of targets. This study proposes a Gaussian particle flow (GPF) Bernoulli filter employing particle flow to migrate particles from prior to posterior positions to improve the performance of the standard Bernoulli filter. By employing the particle flow filter, the computational speed of the Bernoulli filters is significantly improved. In addition, the GPF Bernoulli filter provides a more accurate estimation compared with that of the standard Bernoulli filter. Simulation results confirm the improved tracking performance and computational speed in two- and three-dimensional scenarios compared with other algorithms.Keywords: Bernoulli filter, particle filter, particle flow filter, random finite sets, target tracking
Procedia PDF Downloads 8019538 Dowry System and Gender Discrimination
Authors: Vanitha Dapparabail
Abstract:
Dowry is a system attached to Indian marriage system, it is practice of exchanging the goods and articles in a majority of Indian weddings. Although its practice became illegal in 1961, dowry flourishes among all social classes. Families of the bride and groom negotiate transfer of assets to the groom and his family in exchange for marrying the bride, often within the context of an arranged marriage. Dissatisfaction with the amount of dowry may result in abuse of the bride. In extreme cases “dowry deaths” or the murder of the bride by her husband and his family take place. This article conducts a feminist psychological analysis of the dowry phenomenon, its link to domestic violence against women, and the role of the perpetrators. Existing and new explanations of the dowry system and its ramifications are explored. Psychologically dowry system is greater mental stress for the Indian women and it is a really a part of gender discrimination. This part of the study can explore the amount of gender discrimination in Indian society.Keywords: Dowry system, violence, gender discrimination, India
Procedia PDF Downloads 47319537 Management of Empty Containers by Consignees in the Hinterland
Authors: Benjamin Legros, Jan Fransoo, Oualid Jouini
Abstract:
This study aims to evaluate street-turn strategies for empty container repositioning in the hinterland. Containers arrive over time at the (importer) consignee, while the demand for containers arises from the (exporter) shipper. A match can be operated between an empty container from the consignee and the load from the shipper. Therefore, we model the system as a double-ended queue with non-zero matching time and a limited number of resources in order to optimize the reposition- ing decisions. We determine the performance measures when the consignee operates using a fixed withholding threshold policy. We show that the matching time mainly plays a role in the matching proportion, while under a certain duration, it only marginally impacts the consignee’s inventory policy and cost per container. Also, the withholding level is mainly determined by the shipper’s production rate.Keywords: container, double-ended queue, inventory, Markov decision process, non-zero matching time, street-turn
Procedia PDF Downloads 13119536 Heat Transfer Studies on CNT Nanofluids in a Turbulent Flow Heat Exchanger
Authors: W. Rashmi, M. Khalid, O. Seiksan, R. Saidur, A. F. Ismail
Abstract:
Nanofluids have received much more attention since its discovery. They are believed to be promising coolants in heat transfer applications due to their enhanced thermal conductivity and heat transfer characteristics. In this study, the enhancement in heat transfer of CNT-nanofluids under turbulent flow conditions is investigated experimentally. Carbon nanotube (CNTs) concentration was varied between 0.051-0.085 wt%. The nanofluid suspension was stabilized by gum arabic (GA) through a process of homogenisation and sonication. The flow rates of cold fluid (water) is varied from 1.7-3 L/min and flow rates of the hot fluid is varied between 2-3.5 L/min. Thermal conductivity, density and viscosity of the nanofluids were also measured as a function of temperature and CNT concentration. The experimental results are validated with theoretical correlations for turbulent flow available in the literature. Results showed an enhancement in heat transfer range between 9-67% as a function of temperature and CNT concentration.Keywords: nanofluids, carbon nanotubes (CNT), heat transfer enhancement, heat transfer
Procedia PDF Downloads 49319535 AI In Health and Wellbeing - A Seven-Step Engineering Method
Authors: Denis Özdemir, Max Senges
Abstract:
There are many examples of AI-supported apps for better health and wellbeing. Generally, these applications help people to achieve their goals based on scientific research and input data. Still, they do not always explain how those three are related, e.g. by making implicit assumptions about goals that hold for many but not for all. We present a seven-step method for designing health and wellbeing AIs considering goal setting, measurable results, real-time indicators, analytics, visual representations, communication, and feedback. It can help engineers as guidance in developing apps, recommendation algorithms, and interfaces that support humans in their decision-making without patronization. To illustrate the method, we create a recommender AI for tiny wellbeing habits and run a small case study, including a survey. From the results, we infer how people perceive the relationship between them and the AI and to what extent it helps them to achieve their goals. We review our seven-step engineering method and suggest modifications for the next iteration.Keywords: recommender systems, natural language processing, health apps, engineering methods
Procedia PDF Downloads 15019534 The Algorithmic Dilemma: Virtue Development in the Midst of Role Conflict and Role Ambiguity in Platform Work
Authors: Thumesha Jayatilake
Abstract:
As platform work continues to proliferate, algorithmic management, which takes care of its operational role, poses complex challenges, including job satisfaction, worker involvement, ethical decision-making, and worker well-being. This conceptual paper scrutinizes how algorithmic management influences virtue development among platform workers, with an emphasis on the effects of role conflict and role ambiguity. Using an interdisciplinary approach, the research elucidates the complex relationship between algorithmic management systems and the ethical dimensions of work. The study also incorporates the interplay of human interaction and short-term task orientation, thus broadening the understanding of the impacts of algorithmic management on virtue development. The findings have significant implications for policymakers, academics, and industry practitioners, illuminating the ethical complexities presented by the use of algorithms in modern employment settings.Keywords: algorithmic management, ethics, platform work, virtue
Procedia PDF Downloads 5819533 Methods Used to Perform Requirements Elicitation for FinTech Application Development
Authors: Zhao Pengcheng, Yin Siyuan
Abstract:
Fintech is the new hot topic of the 21st century, a discipline that combines financial theory with computer modelling. It can provide both digital analysis methods for investment banks and investment decisions for users. Given the variety of services available, it is necessary to provide a superior method of requirements elicitation to ensure that users' needs are addressed in the software development process. The accuracy of traditional software requirements elicitation methods is not sufficient, so this study attempts to use a multi-perspective based requirements heuristic framework. Methods such as interview and questionnaire combination, card sorting, and model driven are proposed. The collection results from PCA show that the new methods can better help with requirements elicitation. However, the method has some limitations and, there are some efficiency issues. However, the research in this paper provides a good theoretical extension that can provide researchers with some new research methods and perspectives viewpoints.Keywords: requirement elicitation, FinTech, mobile application, survey, interview, model-driven
Procedia PDF Downloads 9719532 Secondary Metabolites from Turkish Marine-Derived Fungi Hypocrea nigricans
Authors: H. Heydari, B. Konuklugil, P. Proksch
Abstract:
Marine-derived fungi can produce interesting bioactive secondary metabolites that can be considered the potential for drug development. Turkey is a country of a peninsula surrounded by the Black Sea at the north, the Aegean Sea at the west, and the Mediterranean Sea at the south. Despite the approximately 8400 km of coastline, studies on marine secondary metabolites and their biological activity are limited. In our ongoing search for new natural products with different bioactivities produced by the marine-derived fungi, we have investigated secondary metabolites of Turkish collection of the marine sea slug (Peltodoris atromaculata) associated fungi Hypocrea nigricans collected from Seferihisar in the Egean sea. According to the author’s best knowledge, no study was found on this fungal species in terms of secondary metabolites. Isolated from ethyl acetate extract of the culture of Hypocrea nigricans were (isodihydroauroglaucin,tetrahydroauroglaucin and dihydroauroglaucin. The structures of the compounds were established based on an NMR and MS analysis. Structural elucidation of another isolated secondary metabolite/s continues.Keywords: Hypocrea nigricans, isolation, marine fungi, secondary metabolites
Procedia PDF Downloads 15219531 Experimental Study on Flexural Strength of Reinforced Geopolymer Concrete Beams
Authors: Khoa Tan Nguyen, Tuan Anh Le, Kihak Lee
Abstract:
This paper presents the flexural response of Reinforced Geopolymer Concrete (RGPC) beams. A commercial finite element (FE) software ABAQUS has been used to perform a structural behavior of RGPC beams. Using parameters such: stress, strain, Young’s modulus, and Poisson’s ratio obtained from experimental results, a beam model has been simulated in ABAQUS. The results from experimental tests and ABAQUS simulation were compared. Due to friction forces at the supports and loading rollers; slip occurring, the actual deflection of RGPC beam from experimental test results were slightly different from the results of ABAQUS. And there is good agreement between the crack patterns of fly ash-based geopolymer concrete generated by FE analysis using ABAQUS, and those in experimental data.Keywords: geopolymer concrete beam, finite element mehod, stress strain relation, modulus elasticity
Procedia PDF Downloads 37619530 Polarization Dependent Flexible GaN Film Nanogenerators and Electroluminescence Properties
Authors: Jeong Min Baik
Abstract:
We present that the electroluminescence (EL) properties and electrical output power of flexible N-face p-type GaN thin films can be tuned by strain-induced piezo-potential generated across the metal-semiconductor-metal structures. Under different staining conditions (convex and concave bending modes), the transport properties of the GaN films can be changed due to the spontaneous polarization of the films. The I-V characteristics with the bending modes show that the convex bending can increase the current across the films by the decrease in the barrier height at the metal-semiconductor contact, increasing the EL intensity of the P-N junction. At convex bending, it is also shown that the flexible p-type GaN films can generate an output voltage of up to 1.0 V, while at concave bending, 0.4 V. The change of the band bending with the crystal polarity of GaN films was investigated using high-resolution photoemission spectroscopy. This study has great significance on the practical applications of GaN in optoelectronic devices and nanogenerators under a working environment.Keywords: GaN, flexible, laser lift-off, nanogenerator
Procedia PDF Downloads 40919529 Monitoring of Rice Phenology and Agricultural Practices from Sentinel 2 Images
Authors: D. Courault, L. Hossard, V. Demarez, E. Ndikumana, D. Ho Tong Minh, N. Baghdadi, F. Ruget
Abstract:
In the global change context, efficient management of the available resources has become one of the most important topics, particularly for sustainable crop development. Timely assessment with high precision is crucial for water resource and pest management. Rice cultivated in Southern France in the Camargue region must face a challenge, reduction of the soil salinity by flooding and at the same time reduce the number of herbicides impacting negatively the environment. This context has lead farmers to diversify crop rotation and their agricultural practices. The objective of this study was to evaluate this crop diversity both in crop systems and in agricultural practices applied to rice paddy in order to quantify the impact on the environment and on the crop production. The proposed method is based on the combined use of crop models and multispectral data acquired from the recent Sentinel 2 satellite sensors launched by the European Space Agency (ESA) within the homework of the Copernicus program. More than 40 images at fine spatial resolution (10m in the optical range) were processed for 2016 and 2017 (with a revisit time of 5 days) to map crop types using random forest method and to estimate biophysical variables (LAI) retrieved by inversion of the PROSAIL canopy radiative transfer model. Thanks to the high revisit time of Sentinel 2 data, it was possible to monitor the soil labor before flooding and the second sowing made by some farmers to better control weeds. The temporal trajectories of remote sensing data were analyzed for various rice cultivars for defining the main parameters describing the phenological stages useful to calibrate two crop models (STICS and SAFY). Results were compared to surveys conducted with 10 farms. A large variability of LAI has been observed at farm scale (up to 2-3m²/m²) which induced a significant variability in the yields simulated (up to 2 ton/ha). Observations on more than 300 fields have also been collected on land use. Various maps were elaborated, land use, LAI, flooding and sowing, and harvest dates. All these maps allow proposing a new typology to classify these paddy crop systems. Key phenological dates can be estimated from inverse procedures and were validated against ground surveys. The proposed approach allowed to compare the years and to detect anomalies. The methods proposed here can be applied at different crops in various contexts and confirm the potential of remote sensing acquired at fine resolution such as the Sentinel2 system for agriculture applications and environment monitoring. This study was supported by the French national center of spatial studies (CNES, funded by the TOSCA).Keywords: agricultural practices, remote sensing, rice, yield
Procedia PDF Downloads 26819528 Corporate Cash Holdings and the Effect of Chaebol Affiliated on the Implied Cost of Equity Capital: Evidence from Korea
Authors: Hongmin Chun
Abstract:
This paper examines corporate cash holdings and their effect on the cost of equity capital. In addition, this study examines the potentially different effects when the firm belongs to chaebol and non-chaebol groups. Chaebol is a South Korean form of business conglomerate. Chaebol is typically global multinationals and owns numerous international enterprises, controlled by a chairman with power over all the operations. The overall empirical result suggests that higher cash holdings are a risk increasing factor which holds for the chaebol group of firms. This result is valid in a battery of robustness tests and 2SLS regressions. In Korea, higher cash holdings represent a risk premium factor that is closely related to the overinvestment and agency problems between managers and shareholders.Keywords: cash holdings, implied cost of equity capital, chaebol, agency problem
Procedia PDF Downloads 165