Search results for: flow experience
4616 SEM Analysis of the Effectiveness of the Acid Etching on Cat Enamel
Authors: C. Gallottini, W. Di Mari, C. De Carolis, A. Dolci, G. Dolci, L. Gallottini, G. Barraco, S. Eramo
Abstract:
The aim of this paper is to summarize the literature on micromorphology and composition of the enamel of the cat and present an original experiment by SEM on how it responds to the etching with ortophosphoric acid for the time recommended in the veterinary literature (30", 45", 60"), derived from research and experience on human enamel; 21 teeth of cat were randomly divided into three groups of 7 (A, B, C): Group A was subjected to etching for 30 seconds by means of orthophosphoric acid to 40% on a circular area with diameter of about 2mm of the enamel coronal; the Groups B and C had the same treatment but, respectively, for 45 and 60 seconds. The samples obtained were observed by SEM to constant magnification of 1000x framing, in particular, the border area between enamel exposed and not exposed to etching to highlight differences. The images were subjected to the analysis of three blinded experienced operators in electron microscopy. In the enamel of the cat the etching for the times considered is not optimally effective for the purpose adhesives and the presence of a thick prismless layer could explain this situation. To improve this condition may clinically in the likeness of what is proposed for the enamel of human deciduous teeth: a bevel or a chamfer of 1 mm on the contour of the cavity to discover the prismatic enamel and increase the bonding surface.Keywords: cat enamel, SEM, veterinary dentistry, acid etching
Procedia PDF Downloads 3074615 An Approach from Fichte as a Response to the Kantian Dualism of Subject and Object: The Unity of the Subject and Object in Both Theoretical and Ethical Possibility
Authors: Mengjie Liu
Abstract:
This essay aims at responding to the Kant arguments on how to fit the self-caused subject into the deterministic object which follows the natural laws. This essay mainly adopts the approach abstracted from Fichte’s “Wissenshaftslehre” (Doctrine of Science) to picture a possible solution to the conciliation of Kantian dualism. The Fichte approach is based on the unity of the theoretical and practical reason, which can be understood as a philosophical abstraction from ordinary experience combining both subject and object. This essay will discuss the general Kantian dualism problem and Fichte’s unity approach in the first part. Then the essay will elaborate on the achievement of this unity of the subject and object through Fichte’s “the I posits itself” process in the second section. The following third section is related to the ethical unity of subject and object based on the Fichte approach. The essay will also discuss the limitation of Fichte’s approach from two perspectives: (1) the theoretical possibility of the existence of the pure I and (2) Schelling’s statement that the Absolute I is a result rather than the originating act. This essay demonstrates a possible approach to unifying the subject and object supported by Fichte’s “Absolute I” and ethical theories and also points out the limitations of Fichte’s theories.Keywords: Fichte, identity, Kantian dualism, Wissenshaftslehre
Procedia PDF Downloads 914614 A Practical Guide to Collaborative Writing Assignments as a Pedagogical Technique in Higher Education Implemented in an Economics Course
Authors: Bahia Braktia, Belkacem Braktia
Abstract:
Collaborative writing is now an established pedagogical technique in higher education. Since most educators do not have training in the design, execution, and evaluation of writing assignments, implementing such tasks has proven difficult. This paper firstly proposes a framework for a collaborative writing assignment based on a literature study and adopting a writing-to-learn concept. It then describes the research undertaken and shows how this framework is implemented in an economics course, at an Algerian university, with undergraduate students. Finally, using a mixed methods design, it examines the students’ perceptions of what they have learned about collaborative writing. Preliminary results show that group assignments will always be a challenge, but with careful planning and structure, a collaborative writing assignment can be used effectively to help students improve their analytical and critical thinking abilities, research and group work skills, as well as writing proficiency. Students have a positive experience of working in a team and identified a wide variety of different team skills that they have learned through the process.Keywords: collaborative writing, research assignment, students’ perception, survey
Procedia PDF Downloads 2044613 An Experimental Investigation of Microscopic and Macroscopic Displacement Behaviors of Branched-Preformed Particle Gel in High Temperature Reservoirs
Authors: Weiyao Zhu, Bingbing Li, Yajing Liu, Zhiyong Song
Abstract:
Branched-preformed particle gel (B-PPG) is a newly developed profile control and oil displacement agent for enhanced oil recovery in major oilfields. To provide a better understanding of the performance of B-PPG in high temperature reservoirs, a comprehensive experimental investigation was conducted by utilizing glass micromodel and synthetic core. The microscopic experimental results show that the B-PPG can selectively flow and plug in large pores. In terms of enhanced oil recovery, the decrease of residual oil in the margin regions (24.6%) was higher than that in the main stream (13.7%), which indicates it enlarged the sweep area. In addition, the effects of B-PPG injection concentration and injection rate on enhanced oil recovery were implemented by core flooding. The macroscopic experimental results indicate that the enhanced oil recovery increased with the increasing of injection concentration. However, the injection rate had a peak value. It is significant to get insight into the behaviors of B-PPG in reservoirs.Keywords: branched-preformed particle gel, enhanced oil recovery, micromodel, core flooding
Procedia PDF Downloads 1984612 Long-Term Exposure Assessments for Cooking Workers Exposed to Polycyclic Aromatic Hydrocarbons and Aldehydes Containing in Cooking Fumes
Authors: Chun-Yu Chen, Kua-Rong Wu, Yu-Cheng Chen, Perng-Jy Tsai
Abstract:
Cooking fumes are known containing polycyclic aromatic hydrocarbons (PAHs) and aldehydes, and some of them have been proven carcinogenic or possibly carcinogenic to humans. Considering their chronic health effects, long-term exposure data is required for assessing cooking workers’ lifetime health risks. Previous exposure assessment studies, due to both time and cost constraints, mostly were based on the cross-sectional data. Therefore, establishing a long-term exposure data has become an important issue for conducting health risk assessment for cooking workers. An approach was proposed in this study. Here, the generation rates of both PAHs and aldehydes from a cooking process were determined by placing a sampling train exactly under the under the exhaust fan under the both the total enclosure condition and normal operating condition, respectively. Subtracting the concentration collected by the former (representing the total emitted concentration) from that of the latter (representing the hood collected concentration), the fugitive emitted concentration was determined. The above data was further converted to determine the generation rates based on the flow rates specified for the exhaust fan. The determinations of the above generation rates were conducted in a testing chamber with a selected cooking process (deep-frying chicken nuggets under 3 L peanut oil at 200°C). The sampling train installed under the exhaust fan consisted respectively an IOM inhalable sampler with a glass fiber filter for collecting particle-phase PAHs, followed by a XAD-2 tube for gas-phase PAHs. The above was also used to sample aldehydes, however, installed with a filter pre-coated with DNPH, and followed by a 2,4-DNPH-cartridge for collecting particle-phase and gas-phase aldehydes, respectively. PAHs and aldehydes samples were analyzed by GC/MS-MS (Agilent 7890B), and HPLC-UV (HITACHI L-7100), respectively. The obtained generation rates of both PAHs and aldehydes were applied to the near-field/ far-field exposure model to estimate the exposures of cooks (the estimated near-field concentration), and helpers (the estimated far-field concentration). For validating purposes, both PAHs and aldehydes samplings were conducted simultaneously using the same sampling train at both near-field and far-field sites of the testing chamber. The sampling results, together with the use of the mixed-effect model, were used to calibrate the estimated near-field/ far-field exposures. In the present study, the obtained emission rates were further converted to emission factor of both PAHs and aldehydes according to the amount of food oil consumed. Applying the long-term food oil consumption records, the emission rates for both PAHs and aldehydes were determined, and the long-term exposure databanks for cooks (the estimated near-field concentration), and helpers (the estimated far-field concentration) were then determined. Results show that the proposed approach was adequate to determine the generation rates of both PAHs and aldehydes under various fan exhaust flow rate conditions. The estimated near-field/ far-field exposures, though were significantly different from that obtained from the field, can be calibrated using the mixed effect model. Finally, the established long-term data bank could provide a useful basis for conducting long-term exposure assessments for cooking workers exposed to PAHs and aldehydes.Keywords: aldehydes, cooking oil fumes, long-term exposure assessment, modeling, polycyclic aromatic hydrocarbons (PAHs)
Procedia PDF Downloads 1424611 The Intercultural Communicative Competence (ICC) Perspective in the Film Classroom
Authors: Yan Zhang
Abstract:
With the development of commercial movies, more and more instructors are drawn to adapt film pedagogy to teach history and culture. By challenging traditional standards of classroom culture, instruction through film represents an intersection of modernity and adaptability which is no longer optional but essential to maintaining educational accessibility. First, this presentation describes special features of the film that can be used in the classroom and help students acquire intercultural communicative competence (ICC) and achieve the learning goal. Second, the author brings forward the 5 A STAIRCASE model (Acknowledge-Adjust-Acculturate-Act-Assess) to explore how students acquire international communicative competence. Third, this article presents the intersections between new digital environments and classroom practice, such as how films can contribute to combining classical and contemporary Chinese cultures seamlessly and how film pedagogy can be an effective way to get students to engage in deeper critical thinking by exposing them to visuals, music, language, and styling which do not exist in traditional learning formats. Last, the student’s final video project will be exemplified at the end, demonstrating how to engage students in the analysis and experience of history and culture.Keywords: intercultural education, curriculum, media, history
Procedia PDF Downloads 744610 The World of Fireworks Factory Working Children in Bocaue, Bulacan
Authors: Agnes Crisostomo, Alvin Joseph Mapoy
Abstract:
This is a qualitative study which focuses on ten (10) children, with a mean age of 13.6, working in fireworks factories in Bocaue, Bulacan. The municipality of Bocaue was chosen since it is the center of trade for fireworks, and child laborers can easily penetrate in factories here. The researcher wanted to know what the possible negative effects are caused by working at an early age of a child in the physical, psychosocial, intellectual and emotional aspects of life. Results showed that social status of their parents and their lack of income forced the children to work for their family. Second, the child laborers still allot time for studying. They still do not give up in pursuing education even if they experience fatigue and illness which affect their physical development. Third, working has a great influence to the child’s life. Fourth, through socializing with others, they become more aware of life’s hardships. Usually, their co-workers are also their family members and friends; this is how they know the social status is their place, that due to poverty even the children should work for a living. Fifth, these child laborers are still hoping for a better future. Despite of their poor situation, they are still hoping that they can turn it upside down through education, perseverance and determination.Keywords: child labor, emotional, intellectual, psychosocial
Procedia PDF Downloads 2654609 Entropy Generation of Natural Convection Heat Transfer in a Square Cavity Using Al2O3-Water Nanofluid
Authors: M. Alipanah, A. Ranjbar, E. Farnad, F. Alipanah
Abstract:
Entropy generation of an Al2O3-water nanofluid due to heat transfer and fluid friction irreversibility has been investigated in a square cavity subject to different side wall temperatures using a nanofluid for natural convection flow. This study has been carried out for the pertinent parameters in the following ranges: Rayleigh number between 104 to 107 and volume fraction between 0 to 0.05. Based on the obtained dimensionless velocity and temperature values, the distributions of local entropy generation, average entropy generation and average Bejan number are determined. The results are compared for a pure fluid and a nanofluid. It is totally found that the heat transfer and entropy generation of the nanofluid is more than the pure fluid and minimum entropy generation and Nusselt number occur in the pure fluid at any Rayleigh number. Results depict that the addition of nanoparticles to the pure fluid has more effect on the entropy generation as the Rayleigh number goes up.Keywords: entropy generation, natural convection, bejan number, nuselt number, nanofluid
Procedia PDF Downloads 4994608 Lessons Learned on a Reverse Field Trip: A Field Study of Prospective Students
Authors: Matthew David Marmet
Abstract:
Knowing your audience is important regardless of what profession you are in. Whether this audience is comprised of customers or students, having an idea of who these people are, where they come from, and some of the challenges they may have faced allows us to build better relationships with them. This paper will recap a field study experience that has been dubbed a "reverse field trip" to a local high school. Here, going back in time produced not only a great deal of nostalgia, but also served as a reminder of who prospective university students are before they arrive. This information is invaluable as it can help inform classroom (and other) strategies that may help them succeed, and persist through the college years, which will no doubt present them with undeniable changes and challenges. Interviews with school staff and observations of student behavior, both inside and outside the classroom, yielded several lessons learned (i.e., issues to address). These include considerations of regimen, three separate yet related levels of context, and expectation-setting. Each issue will be presented in detail, along with pedagogical strategies to help address them. These strategies have both student-level and institutional benefits as they have the potential not only to increase student engagement, but also improve retention rates.Keywords: pedagogy, Student engagement, student retention, teaching strategy
Procedia PDF Downloads 844607 Using Electro-Biogrouting to Stabilize of Soft Soil
Authors: Hamed A. Keykha, Hadi Miri
Abstract:
This paper describes a new method of soil stabilisation, electro-biogrouting (EBM), for improvement of soft soil with low hydraulic conductivity. This method uses an applied voltage gradient across the soil to induce the ions and bacteria cells through the soil matrix, resulting in CaCO3 precipitation and an increase of the soil shear strength in the process. The EBM were used effectively with two injection methods; bacteria injection and products of bacteria injection. The bacteria cells, calcium ions and urea were moved across the soil by electromigration and electro osmotic flow respectively. The products of bacteria (CO3-2) were moved by electromigration. The results showed that the undrained shear strength of the soil increased from 6 to 65 and 70 kPa for first and second injection method respectively. The injection of carbonate solution and calcium could be effectively flowed in the clay soil compare to injection of bacteria cells. The detection of CaCO3 percentage and its corresponding water content across the specimen showed that the increase of undrained shear strength relates to the deposit of calcite crystals between soil particles.Keywords: Sporosarcina pasteurii, electrophoresis, electromigration, electroosmosis, biocement
Procedia PDF Downloads 5284606 Effect of Model Dimension in Numerical Simulation on Assessment of Water Inflow to Tunnel in Discontinues Rock
Authors: Hadi Farhadian, Homayoon Katibeh
Abstract:
Groundwater inflow to the tunnels is one of the most important problems in tunneling operation. The objective of this study is the investigation of model dimension effects on tunnel inflow assessment in discontinuous rock masses using numerical modeling. In the numerical simulation, the model dimension has an important role in prediction of water inflow rate. When the model dimension is very small, due to low distance to the tunnel border, the model boundary conditions affect the estimated amount of groundwater flow into the tunnel and results show a very high inflow to tunnel. Hence, in this study, the two-dimensional universal distinct element code (UDEC) used and the impact of different model parameters, such as tunnel radius, joint spacing, horizontal and vertical model domain extent has been evaluated. Results show that the model domain extent is a function of the most significant parameters, which are tunnel radius and joint spacing.Keywords: water inflow, tunnel, discontinues rock, numerical simulation
Procedia PDF Downloads 5244605 Practitioner System in Vocational Education: Perspectives of Academics and Industry Practitioners
Authors: Hsiao-Tseng Lin, Nguyen Ngoc Dat, Szu-Mei Hsiao, R. J. Hernández-Díaz
Abstract:
The practitioner system has become an important tool for universities working to shrink the gap between industry and vocational education. Beginning in 2015, Meiho University conducted a consecutive three-year program for teaching excellence, funded in part by Taiwan’s Ministry of Education, with a total project funding of over $2.5 million USD. One of the highlights of this program is the recruitment of 300 industry practitioners to participate in collaborative teaching, a dual-mentor system, and curriculum planning. More than 60% of the practitioners boast more than 10 years of practical industry experience, and 52% of them have earned master's degree or higher. Students rated their overall program satisfaction over 4.5(out of 5.0) on average. This study explores the perspectives of academics and industry practitioners using in-depth interviews and surveys, along with an examination of the challenges of the practitioner system. The paper enables the framing of practitioner system policies by vocational education institutions and industry to facilitate more effective and efficient transfer of knowledge between academics and practitioners, leading to enhanced university competitive advantage, which would ultimately benefit society.Keywords: collaborative teaching, industry practitioners, practitioner system, vocational education
Procedia PDF Downloads 2124604 Research on Knowledge Graph Inference Technology Based on Proximal Policy Optimization
Authors: Yihao Kuang, Bowen Ding
Abstract:
With the increasing scale and complexity of knowledge graph, modern knowledge graph contains more and more types of entity, relationship, and attribute information. Therefore, in recent years, it has been a trend for knowledge graph inference to use reinforcement learning to deal with large-scale, incomplete, and noisy knowledge graph and improve the inference effect and interpretability. The Proximal Policy Optimization (PPO) algorithm utilizes a near-end strategy optimization approach. This allows for more extensive updates of policy parameters while constraining the update extent to maintain training stability. This characteristic enables PPOs to converge to improve strategies more rapidly, often demonstrating enhanced performance early in the training process. Furthermore, PPO has the advantage of offline learning, effectively utilizing historical experience data for training and enhancing sample utilization. This means that even with limited resources, PPOs can efficiently train for reinforcement learning tasks. Based on these characteristics, this paper aims to obtain better and more efficient inference effect by introducing PPO into knowledge inference technology.Keywords: reinforcement learning, PPO, knowledge inference, supervised learning
Procedia PDF Downloads 674603 Comparative Analysis of Turbulent Plane Jets from a Sharp-Edged Orifice, a Beveled-Edge Orifice and a Radially Contoured Nozzle
Authors: Ravinesh C. Deo
Abstract:
This article investigates through experiments the flow characteristics of plane jets from sharp-edged orifice-plate, beveled-edge and radially contoured nozzle. The first two configurations exhibit saddle-backed velocity profiles while the third shows a top-hat. A vena contracta is found for the jet emanating from orifice at x/h = 3 while the contoured case displays a potential core extending to the range x/h = 5. A spurt in jet pressure on the centerline supports vena contracta for the orifice-jet. Momentum thicknesses and integral length scales elongate linearly with x although the growth of the shear-layer and large-scale eddies for the orifice are greater than the contoured case. The near-field spectrum exhibits higher frequency of the primary eddies that concur with enhanced turbulence intensity. Importantly, highly “turbulent” state of the orifice-jet prevails in the far-field where the spectra confirm more energetic secondary eddies associated with greater flapping amplitude of the orifice-jet.Keywords: orifice, beveled-edge-orifice, radially contoured nozzle, plane jets
Procedia PDF Downloads 1544602 Characterization of Genus Candida Yeasts Isolated from Oral Microbiota of Brazilian Schoolchildren with Different Caries Experience
Authors: D. S. V. Barbieri, R. R. Gomes, G. D. Santos, P. F. Herkert, M. Moreira, E. S. Trindade, V. A. Vicente
Abstract:
The importance of yeast infections has increased in recent decades. The monitoring of Candida yeasts has been relevant in the study of groups and populations. This research evaluated 31 Candida spp. isolates from oral microbiota of 12 Brazilian schoolchildren coinfected with Streptococcus mutans. The isolates were evaluated for their ability to form biofilm in vitro and molecularly characterized based on the sequencing of intergenic spacer regions ITS1-5,8S-ITS2 and variable domains of the large subunit (D1/D2) regions of the rDNA, as well as ABC system genotyping. The sequencing confirmed 26 lineages of Candida albicans, three Candida tropicalis, one Candida guillhermondii and one Candida glabrata. Genetic variability and differences on in biofilm formation were observed among Candida yeasts lineages. At least one Candida strain from each caries activity child was C.albicans genotype A or Candida non-albicans. C. tropicalis was associated with highest cavities rates. These results indicate that the presence of C. albicans genotype A or multi-colonization by non albicans species seem to be associates to the potentialization of caries risk.Keywords: biofilm, Candida albicans, oral microbiota, caries
Procedia PDF Downloads 5104601 Investigating Differential Psychological Impact of Translated Movies: An Experimental Design
Authors: Sonakshi Saxena, Moosath Harishankar Vasudevan
Abstract:
The current study seeks to investigate the differences in the psychological impact of movies in their original and translated versions. International cinema is exemplar of the success of globalization. The multitude of languages in the global village does not seem to impede the common cinematic goal of filmmakers across linguistic boundaries. To understand, hence, whether the psychological impact of movies, intentional or otherwise, is preserved when the original is translated into a different language, an experimental design was adopted. Multilingual participants in the age group 18-25 years were recruited for the same. A control group and an experimental group were randomly assigned and the psychological impacts of movies were studied under two conditions- a) watching the movie in its original language, and b) watching the movie in its original language as well as translated version. For the second condition, the experimental group was further divided into two groups randomly to balance order effects. The major aspects of psychological impact assessed were emotional impact and attitude towards the movie. The scores were compared for the two groups. It is further discussed whether the experience is salient across language or do languages inherently possess the ability to alter experiences of the audience.Keywords: experimental design, movies, psychological impact, translation
Procedia PDF Downloads 3974600 To Know the Way to the Unknown: A Semi-Experimental Study on the Implication of Skills and Knowledge for Creative Processes in Higher Education
Authors: Mikkel Snorre Wilms Boysen
Abstract:
From a theoretical perspective, expertise is generally considered a precondition for creativity. The assumption is that an individual needs to master the common and accepted rules and techniques within a certain knowledge-domain in order to create something new and valuable. However, real life cases, and a limited amount of empirical studies, demonstrate that this assumption may be overly simple. In this article, this question is explored through a number of semi-experimental case studies conducted within the fields of music, technology, and youth culture. The studies indicate that, in various ways, expertise plays an important part in creative processes. However, the case studies also indicate that expertise sometimes leads to an entrenched perspective, in the sense that knowledge and experience may work as a path into the well-known rather than into the unknown. In this article, these issues are explored with reference to different theoretical approaches to creativity and learning, including actor-network theory, the theory of blind variation and selective retention, and Csikszentmihalyi’s system model. Finally, some educational aspects and implications of this are discussed.Keywords: creativity, expertise , education, technology
Procedia PDF Downloads 3224599 Effects of Daily Temperature Changes on Transient Heat and Moisture Transport in Unsaturated Soils
Authors: Davood Yazdani Cherati, Ali Pak, Mehrdad Jafarzadeh
Abstract:
This research contains the formulation of a two-dimensional analytical solution to transient heat, and moisture flow in a semi-infinite unsaturated soil environment under the influence of daily temperature changes. For this purpose, coupled energy conservation and mass fluid continuity equations governing hydrothermal behavior of unsaturated soil media are presented in terms of temperature and volumetric moisture content. In consideration of the soil environment as an infinite half-space and by linearization of the governing equations, Laplace–Fourier transformation is conducted to convert differential equations with partial derivatives (PDEs) to ordinary differential equations (ODEs). The obtained ODEs are solved, and the inverse transformations are calculated to determine the solution to the system of equations. Results indicate that heat variation induces moisture transport in both horizontal and vertical directions.Keywords: analytical solution, heat conduction, hydrothermal analysis, laplace–fourier transformation, two-dimensional
Procedia PDF Downloads 2164598 Physical Education Teacher's Interpretation toward Teaching Games for Understanding Model
Authors: Soni Nopembri
Abstract:
The objective of this research is to evaluate the implementation of teaching games for Understanding model by conducting action to physical education teacher who have got long teaching experience. The research applied Participatory Action Research. The subjects of this research were 19 physical education teachers who had got training of Teaching Games for Understanding. Data collection was conducted intensively through a questionnaire, in-depth interview, Focus Group Discussion (FGD), observation, and documentation. The collected data was analysis zed qualitatively and quantitatively. The result showed that physical education teachers had got an appropriate interpretation on TGfU model. Some indicators that were the focus of this research indicated this points; they are: (1) physical education teachers had good understanding toward TGfU model, (2) PE teachers’ competence in applying TGfU model on Physical Education at school were adequate, though some improvement were needed, (3) the influence factors in the implementation of TGfU model, in sequence, were teacher, facilities, environment, and students factors, (4) PE teachers’ perspective toward TGfU model were positively good, although some teachers were less optimistic toward the development of TGfU model in the future.Keywords: TGfU, physical education teacher, teaching games, FGD
Procedia PDF Downloads 5474597 Conceptual Metaphors of Responsibility in Arabic to English Translation of Political Speeches: A Corpus-Based Study
Authors: Amr Anany
Abstract:
This study offers a corpus-based analysis of the conceptual metaphors of RESPONSIBILITY inherent in the Arabic political speeches of King Abdulla II and their English translations rendered by the translators of the Royal Hashemite Court ("RHC translators"). In view of the Conceptual Metaphor Theory (CMT), the current study aims to uncover the extent to which the dominant ideology in the source Arabic speeches of King Abdulla II is conveyed into the target English translation. The study explores a bilingual corpus, including eleven authentic Arabic speeches delivered by King Abdulla II and their English translations. The study finds that both Arabic and English share several metaphorical expressions of RESPONSIBILITY that are based on bodily experience such as RESPONSIBILITY IS UP, RESPONSIBILITY IS AN OBJECT, and RESPONSIBILITY IS AN HONOR. Apparently, the study concludes that RHC translators succeed to convey the dominant ideology from the source Arabic speeches to the English ones using specific translation strategies.Keywords: cognitive linguistics, CDA, conceptual metaphor theory, ideology, responsibility
Procedia PDF Downloads 714596 Effect of Polymer Concentration on the Rheological Properties of Polyelectrolyte Solutions
Authors: Khaled Benyounes, Abderrahmane Mellak
Abstract:
The rheology of aqueous solutions of polyelectrolyte (polyanionic cellulose, PAC) at high molecular weight was investigated using a controlled stress rheometer. Several rheological measurements; viscosity measurements, creep compliance tests at a constant low shear stress and oscillation experiments have been performed. The concentrations ranged by weight from 0.01 to 2.5% of PAC. It was found that the aqueous solutions of PAC do not exhibit a yield stress, the flow curves of PAC over a wide range of shear rate (0 to 1000 s-1) could be described by the cross model and the Williamson models. The critical concentrations of polymer c* and c** have been estimated. The dynamic moduli, i.e., storage modulus (G’) and loss modulus (G’’) of the polymer have been determined at frequency sweep from 0.01 to 10 Hz. At polymer concentration above 1%, the modulus G’ is superior to G’’. The relationships between the dynamic modulus and concentration of polymer have been established. The creep-recovery experiments demonstrated that polymer solutions show important viscoelastic properties of system water-PAC when the concentration of the polymer increases.Keywords: polyanionic cellulose, viscosity, creep, oscillation, cross model
Procedia PDF Downloads 3264595 Numerical Solution of Momentum Equations Using Finite Difference Method for Newtonian Flows in Two-Dimensional Cartesian Coordinate System
Authors: Ali Ateş, Ansar B. Mwimbo, Ali H. Abdulkarim
Abstract:
General transport equation has a wide range of application in Fluid Mechanics and Heat Transfer problems. In this equation, generally when φ variable which represents a flow property is used to represent fluid velocity component, general transport equation turns into momentum equations or with its well known name Navier-Stokes equations. In these non-linear differential equations instead of seeking for analytic solutions, preferring numerical solutions is a more frequently used procedure. Finite difference method is a commonly used numerical solution method. In these equations using velocity and pressure gradients instead of stress tensors decreases the number of unknowns. Also, continuity equation, by integrating the system, number of equations is obtained as number of unknowns. In this situation, velocity and pressure components emerge as two important parameters. In the solution of differential equation system, velocities and pressures must be solved together. However, in the considered grid system, when pressure and velocity values are jointly solved for the same nodal points some problems confront us. To overcome this problem, using staggered grid system is a referred solution method. For the computerized solutions of the staggered grid system various algorithms were developed. From these, two most commonly used are SIMPLE and SIMPLER algorithms. In this study Navier-Stokes equations were numerically solved for Newtonian flow, whose mass or gravitational forces were neglected, for incompressible and laminar fluid, as a hydro dynamically fully developed region and in two dimensional cartesian coordinate system. Finite difference method was chosen as the solution method. This is a parametric study in which varying values of velocity components, pressure and Reynolds numbers were used. Differential equations were discritized using central difference and hybrid scheme. The discritized equation system was solved by Gauss-Siedel iteration method. SIMPLE and SIMPLER were used as solution algorithms. The obtained results, were compared for central difference and hybrid as discritization methods. Also, as solution algorithm, SIMPLE algorithm and SIMPLER algorithm were compared to each other. As a result, it was observed that hybrid discritization method gave better results over a larger area. Furthermore, as computer solution algorithm, besides some disadvantages, it can be said that SIMPLER algorithm is more practical and gave result in short time. For this study, a code was developed in DELPHI programming language. The values obtained in a computer program were converted into graphs and discussed. During sketching, the quality of the graph was increased by adding intermediate values to the obtained result values using Lagrange interpolation formula. For the solution of the system, number of grid and node was found as an estimated. At the same time, to indicate that the obtained results are satisfactory enough, by doing independent analysis from the grid (GCI analysis) for coarse, medium and fine grid system solution domain was obtained. It was observed that when graphs and program outputs were compared with similar studies highly satisfactory results were achieved.Keywords: finite difference method, GCI analysis, numerical solution of the Navier-Stokes equations, SIMPLE and SIMPLER algoritms
Procedia PDF Downloads 3914594 Platform Urbanism: Planning towards Hyper-Personalisation
Authors: Provides Ng
Abstract:
Platform economy is a peer-to-peer model of distributing resources facilitated by community-based digital platforms. In recent years, digital platforms are rapidly reconfiguring the public realm using hyper-personalisation techniques. This paper aims at investigating how urban planning can leapfrog into the digital age to help relieve the rising tension of the global issue of labour flow; it discusses the means to transfer techniques of hyper-personalisation into urban planning for plasticity using platform technologies. This research first denotes the limitations of the current system of urban residency, where the system maintains itself on the circulation of documents, which are data on paper. Then, this paper tabulates how some of the institutions around the world, both public and private, digitise data, and streamline communications between a network of systems and citizens using platform technologies. Subsequently, this paper proposes ways in which hyper-personalisation can be utilised to form a digital planning platform. Finally, this paper concludes by reviewing how the proposed strategy may help to open up new ways of thinking about how we affiliate ourselves with cities.Keywords: platform urbanism, hyper-personalisation, digital inventory, urban accessibility
Procedia PDF Downloads 1154593 Appearance and Magnitude of Dynamic Pressure in Micro-Scale of Subsonic Airflow around Symmetric Objects
Authors: Shehret Tilvaldyev, Jorge Flores-Garay, Alfredo Villanueva, Erwin Martinez, Lazaro Rico
Abstract:
The efficiency of modern transportation is severely compromised by the prevalence of turbulent drag. The high level of turbulent skin-friction occurring, e.g., on the surface of an aircraft, automobiles or the carriage of a high-speed train, is responsible for excess fuel consumption and increased carbon emissions. The environmental, political, and economic pressure to improve fuel efficiency and reduce carbon emissions associated with transportation means that reducing turbulent skin-friction drag is a pressing engineering problem. The dynamic pressure of subsonic airflow around solid objects creates lift, but also induces drag force. This paper is presenting the results of laboratory experiments, investigating appearance and magnitude of dynamic pressure in micro scale of subsonic air flow around right cylinder and symmetrical airfoil.Keywords: airflow, dynamic pressure, micro scale, symmetric object
Procedia PDF Downloads 3824592 Students’ Perception and Patterns of Listening Behaviour in an Online Forum Discussion
Authors: K. L. Wong, I. N. Umar
Abstract:
Online forum is part of a Learning Management System (LMS) environment in which students share opinions. This study attempts to investigate the perceptions of students towards online forum and their patterns of listening behaviour during the forum interaction. The students’ perceptions were measured using a questionnaire, in which seven dimensions were used including online experience, benefits of forum participation, cost of participation, perceived ease of use, usefulness, attitude and intention. Meanwhile, their patterns of listening behaviours were obtained using the log file extracted from the LMS. A total of 25 postgraduate students undertaking a course were involved in this study, and their activities in the forum session were recorded by the LMS and used as a log file. The results from the questionnaire analysis indicated that the students perceived that the forum is easy to use, useful, and bring benefits to them. Also, they showed positive attitude towards online forum, and they have the intention to use it in future. Based on the log data, the participants were also divided into six clusters of listening behaviour, in which they are different in terms of temporality, breadth, depth and speaking level. The findings were compared to previous clusters grouping and future recommendations are also discussed.Keywords: e-learning, learning management system, listening behavior, online forum
Procedia PDF Downloads 4324591 Regenerative Tourism: Industry Readiness for the Big Shift
Authors: Renuka Mahadevan, Maneka Jayasinghe, Dianne Dredge
Abstract:
Over the last two years, tourism has been subject to unprecedented changes, and experts predict further change, especially with respect to travel and tourism choices. As concerns regarding the environment and climate change grow, many tourism industry stakeholders are particularly keen on taking steps to mitigate the adverse impacts of the travel industry to the broader society and environment. This approach and process is commonly referred to as 'Sustainable Tourism'. An emerging concept that extends beyond 'sustainable tourism' is 'Regenerative Tourism', which aims to impact the local systems, society and environment positively. In particular, it aims to provide transformational experiences to tourists and thereby inspire the travellers while the local cultural heritage and traditions are preserved from generation to generation. This study analyses how tourism stakeholders are shifting their attitude towards travel and tourism, particularly regarding its impact on people, places, businesses and the environment. The analysis will be based on a global survey of 1200 businesses, tourism organisations, employees, and travel consumers. The preliminary analysis of responses reveals a high interest towards transformational experiences during travel.Keywords: regenerative tourism, transformational, experience, local systems
Procedia PDF Downloads 714590 Causes of Institutionalization of Children and Adolescents in a Shelter in Brazil
Authors: Eduardo Guilherme, Sabrina Duarte
Abstract:
Shelters or orphanages are institutions responsible for ensuring the physical and mental integrity of children and adolescents who had their rights violated or neglected, whether from a social-leavers, is at personal risk to which they were exposed or the negligence of its parents; in Brazil about twenty thousand children and adolescents living in about five hundred registered shelters that receive funds from the federal government. We evaluated the records of institutionalized children and adolescents from the foundation of municipal shelter in Rio Negro/Parana State, Brazil since June/2000 to February/2015. Institutionalization of the causes cited were: lack of family/guardian material resources, abandonment by parents/guardians, domestic violence, substance abuse of parents/guardians, street experience, orphans and others. In Brazil, poverty and extreme poverty are closely related to the institutionalization of causes of children and adolescents. Census data in 2010, the Brazilian Institute of Geography and Statistics (IBGE) indicate that 40% of Brazilians living in poverty are girls and boys up to 14 years in a total of approximately 23 million individuals. Poverty denies children and adolescents their rights, representing a vulnerability which predisposes to some causes of shelter.Keywords: Brazil, shelter, orphanages, institutionalization
Procedia PDF Downloads 4864589 Lubricant-Impregnated Nanoporous Surfaces for Biofilm Prevention
Authors: Yuen Yee Li Sip, Lei Zhai
Abstract:
Biofilms are formed by the attachment of microorganisms onto substrates via self-synthesized extracellular polymeric substances. They have been observed in the International Space Stations (ISS), in which biofilms can jeopardize the performance of key equipment and can pose health threats to the astronauts. This project aims at building conformal nanoporous surfaces that are infused with lubricant and decorated with antimicrobial nanoparticles while simultaneously evaluating their efficacy in preventing biofilm formation. Lubricant-impregnated surfaces (LIS) are fabricated by using a layer-by-layer assembly of silica nanoparticles to generate conformal nanoporous coatings on substrates and fill the films with fluorinated fluids. LIS has demonstrated excellent repellency to a broad range of liquids, preventing microbe adhesion (anti-biofouling). Silver or copper nanoparticles were deposited on the coatings prior to lubricant infusion in order to provide antimicrobial characteristics to the coating. Surface morphology and biofilm growth were characterized to understand how the coating morphology affects the LIS stability and anti-biofouling behaviors (stationary and in a flow).Keywords: biofilm, coatings, nanoporous, antifouling
Procedia PDF Downloads 1004588 Atmospheric Circulation Patterns Inducing Coastal Upwelling in the Baltic Sea
Authors: Ewa Bednorz, Marek Polrolniczak, Bartosz Czernecki, Arkadiusz Marek Tomczyk
Abstract:
This study is meant as a contribution to the research of the upwelling phenomenon, which is one of the most pronounced examples of the sea-atmosphere coupling. The aim is to confirm the atmospheric forcing of the sea waters circulation and sea surface temperature along the variously oriented Baltic Sea coasts and to find out macroscale and regional circulation patterns triggering upwelling along different sections of this relatively small and semi-closed sea basin. The mean daily sea surface temperature data from the summer seasons (June–August) of the years 1982–2017 made the basis for the detection of upwelling cases. For the atmospheric part of the analysis, monthly indices of the Northern Hemisphere macroscale circulation patterns were used. Besides, in order to identify the local direction of airflow, the daily zonal and meridional regional circulation indices were constructed and introduced to the analysis. Finally, daily regional circulation patterns over the Baltic Sea region were distinguished by applying the principal component analysis to the gridded mean daily sea level pressure data. Within the Baltic Sea, upwelling is the most frequent along the zonally oriented northern coast of the Gulf of Finland, southern coasts of Sweden, and along the middle part of the western Gulf of Bothnia coast. Among the macroscale circulation patterns, the Scandinavian type (SCAND), with a primary circulation center located over Scandinavia, has the strongest impact on the horizontal flow of surface sea waters in the Baltic Sea, which triggers upwelling. An anticyclone center over Scandinavia in the positive phase of SCAND enhances the eastern airflow, which increases upwelling frequency along southeastern Baltic coasts. It was proved in the study that the zonal circulation has a stronger impact on upwelling occurrence than the meridional one, and it could increase/decrease a chance of upwelling formation by more than 70% in some coastal sections. Positive and negative phases of six distinguished regional daily circulation patterns made 12 different synoptic situations which were analyzed in the terms of their influence on the upwelling formation. Each of them revealed some impact on the frequency of upwelling in some coastal section of the Baltic Sea; however, two kinds of synoptic situations seemed to have the strongest influence, namely, the first kind representing pressure patterns enhancing the zonal flow and the second kind representing synoptic patterns with a cyclone/anticyclone centers over southern Scandinavia. Upwelling occurrence appeared to be particularly strongly reliant on the atmospheric conditions in some specific coastal sections, namely: the Gulf of Finland, the south eastern Baltic coasts (Polish and Latvian-Lithuanian section), and the western part of the Gulf of Bothnia. Concluding, it can be stated that atmospheric conditions strongly control the occurrence of upwelling within the Baltic Sea basin. Both local and macroscale circulation patterns expressed by the location of the pressure centers influence the frequency of this phenomenon; however, the impact strength varies, depending on the coastal region. Acknowledgment: This research was funded by the National Science Centre, Poland, grant number 2016/21/B/ST10/01440.Keywords: Baltic Sea, circulation patterns, coastal upwelling, synoptic conditions
Procedia PDF Downloads 1284587 More Than a Game: An Educational Application Where Students Compete to Learn
Authors: Kadir Özsoy
Abstract:
Creating a moderately competitive learning environment is believed to have positive effects on student interest and motivation. The best way today to attract young learners to get involved in a fun, competitive learning experience is possible through mobile applications as these learners mostly rely on games and applications on their phones and tablets to have fun, communicate, look for information and study. In this study, a mobile application called ‘QuizUp’ is used to create a specific game topic for elementary level students at Anadolu University Preparatory School. The topic is specially designed with weekly-added questions in accordance with the course syllabus. Students challenge their classmates or randomly chosen opponents to answer questions related to their course subjects. They also chat and post on the topic’s wall in English. The study aims at finding out students’ perceptions towards the use of the application as a classroom and extra-curricular activity through a survey. The study concludes that educational games boost students’ motivation, lead to increased effort, and positively change their studying habits.Keywords: competitive learning, educational application, effort, motivation 'QuizUp', study habits
Procedia PDF Downloads 358