Search results for: calcaneal inclination
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 173

Search results for: calcaneal inclination

113 Optimal Mitigation of Slopes by Probabilistic Methods

Authors: D. De-León-Escobedo, D. J. Delgado-Hernández, S. Pérez

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A probabilistic formulation to assess the slopes safety under the hazard of strong storms is presented and illustrated through a slope in Mexico. The formulation is based on the classical safety factor (SF) used in practice to appraise the slope stability, but it is introduced the treatment of uncertainties, and the slope failure probability is calculated as the probability that SF<1. As the main hazard is the rainfall on the area, statistics of rainfall intensity and duration are considered and modeled with an exponential distribution. The expected life-cycle cost is assessed by considering a monetary value on the slope failure consequences. Alternative mitigation measures are simulated, and the formulation is used to get the measures driving to the optimal one (minimum life-cycle costs). For the example, the optimal mitigation measure is the reduction on the slope inclination angle.

Keywords: expected life-cycle cost, failure probability, slopes failure, storms

Procedia PDF Downloads 129
112 Additive Manufacturing of Overhangs: From Temporary Supports to Self-Support

Authors: Paulo Mendonca, Nzar Faiq Naqeshbandi

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The objective of this study is to propose an interactive design environment that outlines the underlying computational framework to reach self-supporting overhangs. The research demonstrates the digital printability of overhangs taking into consideration factors related to the geometry design, the material used, the applied support, and the printing set-up of slicing and the extruder inclination. Parametric design tools can contribute to the design phase, form-finding, and stability optimization of self-supporting structures while printing in order to hold the components in place until they are sufficiently advanced to support themselves. The challenge is to ensure the stability of the printed parts in the critical inclinations during the whole fabrication process. Facilitating the identification of parameterization will allow to predict and optimize the process. Later, in the light of the previous findings, some guidelines of simulations and physical tests are given to be conducted for estimating the structural and functional performance.

Keywords: additive manufacturing, overhangs, self-support overhangs, printability, parametric tools

Procedia PDF Downloads 98
111 Gas-Liquid Two Phase Flow Phenomenon in Near Horizontal Upward and Downward Inclined Pipe Orientations

Authors: Afshin J. Ghajar, Swanand M. Bhagwat

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The main purpose of this work is to experimentally investigate the effect of pipe orientation on two phase flow phenomenon. Flow pattern, void fraction and two phase pressure drop is measured in a polycarbonate pipe with an inside diameter of 12.7mm for inclination angles ranging from -20° to +20° using air-water fluid combination. The experimental data covers all flow patterns and the entire range of void fraction typically observed in two phase flow. The effect of pipe orientation on void fraction and two phase pressure drop is justified with reference to the change in flow structure and two phase flow behavior. In addition to this, the top performing void fraction and two phase pressure drop correlations available in the literature are presented and their performance is assessed against the experimental data in the present study and that available in the literature.

Keywords: flow patterns, inclined two phase flow, pressure drop, void fraction

Procedia PDF Downloads 648
110 Examining the Decision-Making Process of Hong Kong High School Students Regarding University Choices after 2019

Authors: Yuanyuan Song

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Following the 2019 protests in Hong Kong, significant shifts occurred within society. This study aims to explore whether these events have had an impact on the university preferences of high school students. To delve into these questions, this research immerses itself in the forefront of Hong Kong's educational landscape. It encompasses field studies, interviews, and questionnaires administered to a diverse range of Hong Kong students, as well as their parents and teachers. The findings uncover that the majority of local Hong Kong students and parents possess a limited understanding of mainland China, and this perception has further soured since 2019. Interestingly, the inclination towards pursuing overseas education, particularly in countries like the UK and Australia, has experienced a steady rise. This trend persists despite the fact that esteemed Chinese universities extend preferential admissions policies to Hong Kong students.

Keywords: higher education, university choices, educational sociology, education in Hongkong

Procedia PDF Downloads 99
109 Effect of Design Parameters on a Two Stage Launch Vehicle Performance

Authors: Assem Sallam, Aly Elzahaby, Ahmed Makled, Mohamed Khalil

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Change in design parameters of launch vehicle affects its overall flight path trajectory. In this paper, several design parameters are introduced to study their effect. Selected parameters are the launch vehicle mass, which is presented in the form of payload mass, the maximum allowable angle of attack the launch vehicle can withstand, the flight path angle that is predefined for the launch vehicle second stage, the required inclination and its effect on the launch azimuth and finally by changing the launch pad coordinate. Selected design parameters are studied for their effect on the variation of altitude, ground range, absolute velocity and the flight path angle. The study gives a general mean of adjusting the design parameters to reach the required launch vehicle performance.

Keywords: launch vehicle azimuth, launch vehicle trajectory, launch vehicle payload, launch pad location

Procedia PDF Downloads 285
108 Numerical Analysis of Rapid Drawdown in Dams Based on Brazilian Standards

Authors: Renato Santos Paulinelli Raposo, Vinicius Resende Domingues, Manoel Porfirio Cordao Neto

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Rapid drawdown is one of the cases referred to ground stability study in dam projects. Due to the complexity generated by the combination of loads and the difficulty in determining the parameters, analyses of rapid drawdown are usually performed considering the immediate reduction of water level upstream. The proposal of a simulation, considering the gradual reduction in water level upstream, requires knowledge of parameters about consolidation and those related to unsaturated soil. In this context, the purpose of this study is to understand the methodology of collection and analysis of parameters to simulate a rapid drawdown in dams. Using a numerical tool, the study is complemented with a hypothetical case study that can assist the practical use of data compiled. The referenced dam presents homogeneous section composed of clay soil, a height of 70 meters, a width of 12 meters, and upstream slope with inclination 1V:3H.

Keywords: dam, GeoStudio, rapid drawdown, stability analysis

Procedia PDF Downloads 232
107 Effects of Heat Source Position on Heat Transfer in an Inclined Square Enclosure Filled with Nanofluids

Authors: Khamis Al Kalbani

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The effects of a uniform heat source position on the heat transfer flow inside an inclined square enclosure filled with different types of nanofluids having various shapes of the nanoparticles are investigated numerically following one component thermal equilibrium model. The effects of the Brownian diffusion of the nanoparticles, magnetic field intensity and orientation are taken into consideration in nanofluid modeling. The heat source is placed in the middle of a wall of the enclosure while the opposite wall of it is kept at different temperature. The other walls of the enclosure are kept insulated. The results indicate that the heat source position significantly controls the heat transfer rates of the nanofluids. The distributions of the average heat transfer rates varying the position of the heat source with respect to the geometry inclination angle are calculated for the first time. The outcomes of the present research may be helpful for designing solar thermal collectors, radiators, building insulators and advanced cooling of a nuclear system.

Keywords: heat source, inclined, square enclosure, nanofluids

Procedia PDF Downloads 278
106 The Influence of Directionality on the Giovanelli Illusion

Authors: Michele Sinico

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In the Giovanelli illusion, some collinear dots appear misaligned, when each dot lies within a circle and the circles are not collinear. In this illusion, the role of the frame of reference, determined by the circles, is considered a crucial factor. Three experiments were carried out to study the influence of directionality of the circles on the misalignment. The adjustment method was used. Participants changed the orthogonal position of each dot, from the left to the right of the sequence, until a collinear sequence of dots was achieved. The first experiment verified the illusory effect of the misalignment. In the second experiment, the influence of two different directionalities of the circles (-0.58° and +0.58°) on the misalignment was tested. The results show an over-normalization on the sequences of the dots. The third experiment tested the misalignment of the dots without any inclination of the sequence of circles (0°). Only a local illusory effect was found. These results demonstrate that the directionality of the circles, as a global factor, can increase the misalignment. The findings also indicate that directionality and the frame of reference are independent factors in explaining the Giovanelli illusion.

Keywords: Giovannelli illusion, visual illusion, directionality, misalignment, the frame of reference

Procedia PDF Downloads 154
105 Attitudes towards Recreation: An Empirical Study of Youth’s Recreation Development in Bida-Nigeria

Authors: Kingsley Ononogbo, Ashiru Bello

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The purpose of this study is to determine the factors responsible for the inclination of the youths of Bida to passive recreation, with a view to finding out whether their occupations influence their attitudes towards active recreation. Using the 5-point Likert scale, a total number of 267 participants were drawn from the two major wards in Bida town. They are Cheniyan and Nassarafu. Study evidence revealed that youths were constrained from participating in active recreation due to preoccupation with family responsibilities and lack of their choices of recreational facilities. The result of the Chi Square Test showed that the youths had positive attitudes towards physical exercises, while the Spearman’s Correlation (r=0.21) signifies a positive but weak correlation. The P- value, however, equals .7610 which is greater than 0.05 and, so significant. The study concluded by suggesting regular enlightenment programmes, focusing on the values of participating in active recreation, and building and maintenance of desired neighborhood recreation facilities for youths, as a measure to encourage them to take part in the active form of recreation.

Keywords: attitudes, Bida, recreation development, recreation of youth

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104 Effect of CuO, Al₂O₃ and ZnO Nanoparticles on the Response Time for Natural Convection

Authors: Mefteh Bouhalleb

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With the recent progress in nanotechnology, nanofluids have excellent potentiality in many modern engineering processes, particularly for solar systems such as concentrated solar power plants (CSP). In this context, a numerical simulation is performed to investigate laminar natural convection nanofluids in an inclined rectangular enclosure. Mass conservation, momentum, and energy equations are numerically solved by the finite volume element method using the SIMPLER algorithm for pressure-velocity coupling. In this work, we tested the acting factors on the system response time, such as the particle volume fraction of nanoparticles, particle material, particle size, an inclination angle of enclosure and Rayleigh number. The results show that the diameter of solid particles and Rayleigh number plays an important role in the system response time. The orientation angle of the cavity affects the system response time. A phenomenon of hysteresis appears when the system does not return to its initial state.

Keywords: nanofluid, nanoparticles, heat transfer, time response

Procedia PDF Downloads 66
103 Induction of Innovation (Districts) in (Spatial) Planning and Policy

Authors: Meera Prajapati

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Technological innovation is important for economic and spatial rejuvenation. Innovation districts from the last decades around university towns offer interesting examples. Planning directs the interplay between economic and urban development in these innovation districts that appear in particular regions with economic benefits as a result of incentives to attract multinational industries in innovation centres, research parks, universities, bio incubator assets, etc. The inclination of the OECED towards developing entrepreneurship and innovation to harness a boost in growth requires sustainable living conditions. This research aims to understand ‘how innovation or knowledge centres affected development policies and helped cities to become a high-tech region?’ Therefore, the economic policies of cities are investigated as well as the location logic of centres and their intertwining with supporting services (health, education, living environment, etc.). Case studies (Eindhoven (The Netherlands) and Ho Chi Minh City (Viet Nam)) position Pune (India) in terms of the planning components of innovation.

Keywords: innovation districts, high-tech regions, smart cities, urban planning and policies

Procedia PDF Downloads 117
102 The Study of Sintered Wick Structure of Heat Pipes with Excellent Heat Transfer Capabilities

Authors: Im-Nam Jang, Yong-Sik Ahn

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In this study sintered wick was formed in a heat pipe through the process of sintering a mixture of copper powder with particle sizes of 100μm and 200μm, mixed with a pore-forming agent. The heat pipe's thermal resistance, which affects its heat transfer efficiency, is determined during manufacturing according to powder type, thickness of the sintered wick, and filling rate of the working fluid. Heat transfer efficiency was then tested at various inclination angles (0°, 45°, 90°) to evaluate the performance of heat pipes. Regardless of the filling amount and test angle, the 200μm copper powder type exhibited superior heat transfer efficiency compared to the 100μm type. After analyzing heat transfer performance at various filling rates between 20% and 50%, it was determined that the heat pipe's optimal heat transfer capability occurred at a working fluid filling rate of 30%. The width of the wick was directly related to the heat transfer performance.

Keywords: heat pipe, heat transfer performance, effective pore size, capillary force, sintered wick

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101 Wellbore Spiraling Induced through Systematic Micro-Sliding

Authors: Christopher Viens, Bosko Gajic, Steve Krase

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Stick-Slip is a term that is often overused and commonly diagnosed from surface drilling parameters of torque and differential pressure, but the actual magnitude of the condition is rarely captured at the BHA level as the necessary measurements are seldom deployed. Deployment of an accurate stick-slip measurement downhole has led to an interesting discovery that goes against long held traditional drilling lore. A divide has been identified between stick-slip as independent bit and BHA conditions. This phenomenon in horizontal laterals is common, but few M/LWD systems have been able to capture it. Utilizing measurements of downhole RPM bore pressure, high-speed magnetometer data, bending moment, and continuous inclination, the wellbore spiraling phenomenon is able to be captured, quantified, and intimately tied back to systematic effects of BHA stalling and micro-sliding. An operator in the Permian Basin has identified that this phenomenon is contributing to increased tortuosity and drag. Utilizing downhole torque measurements the root causes of the stick-slip and spiraling phenomenon were identified and able to engineered out of the system.

Keywords: bending moment, downhole dynamics measurements, micro sliding, wellbore spiraling

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100 Numerical Simulation of Solar Reactor for Water Disinfection

Authors: A. Sebti Bouzid, S. Igoud, L. Aoudjit, H. Lebik

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Mathematical modeling and numerical simulation have emerged over the past two decades as one of the key tools for design and optimize performances of physical and chemical processes intended to water disinfection. Water photolysis is an efficient and economical technique to reduce bacterial contamination. It exploits the germicidal effect of solar ultraviolet irradiation to inactivate pathogenic microorganisms. The design of photo-reactor operating in continuous disinfection system, required tacking in account the hydrodynamic behavior of water in the reactor. Since the kinetic of disinfection depends on irradiation intensity distribution, coupling the hydrodynamic and solar radiation distribution is of crucial importance. In this work we propose a numerical simulation study for hydrodynamic and solar irradiation distribution in a tubular photo-reactor. We have used the Computational Fluid Dynamic code Fluent under the assumption of three-dimensional incompressible flow in unsteady turbulent regimes. The results of simulation concerned radiation, temperature and velocity fields are discussed and the effect of inclination angle of reactor relative to the horizontal is investigated.

Keywords: solar water disinfection, hydrodynamic modeling, solar irradiation modeling, CFD Fluent

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99 Designing and Costing the Concept of Servicer Satellites That Can Be Used to De-Orbit Space Debris

Authors: Paras Adlakha

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Today the major threat to our existing and future satellites is space debris; the collision of bodies like defunct satellites with any other objects in space, including the new age ASAT (anti-satellite) weaponry system, are the main causes of the increasing amount of space debris every year. After analyzing the current situation of space debris, low earth orbit is found to be having a large density of debris as compared to any other orbit range; that's why it is selected as the target orbit for space debris removal mission. In this paper, the complete data of 24000 debris is studied based on size, altitude, inclination, mass, number of existing satellites threaten by each debris from which the rocket bodies are the type of wreckage found to be most suited for removal. The optimal method of active debris removal using a robotic arm for capturing the body to attach a de-orbit kit is used to move the debris from its orbit without making the actual contact of servicer with the debris to reduce the further the threat of collision with defunct material. The major factors which are brought into consideration while designing the concept of debris removal are tumbling, removal of debris under a low-cost mission and decreasing the factor of collisions during the mission.

Keywords: de-orbit, debris, servicer, satellite, space junk

Procedia PDF Downloads 107
98 Wave Interaction with Single and Twin Vertical and Sloped Porous Walls

Authors: Mohamad Alkhalidi, S. Neelamani, Noor Alanjari

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The main purpose of harbors and marinas is to create a calm and safe docking space for marine vessels. Standard rubble mound breakwaters, although widely used, occupy port space and require large amounts of stones or rocks. Kuwait does not have good quality stone, so they are imported at a very high cost. Therefore, there is a need for a new wave energy dissipating structure where stones and rocks are scarce. While permeable slotted vertical walls have been proved to be a suitable alternative to rubble mound breakwaters, the introduction of sloped slotted walls may be more efficient in dissipating wave energy. For example, two slotted barriers with 60degree inclination may be equivalent to three vertical slotted barriers from wave energy dissipation point of view. A detailed physical model study is carried out to determine the effects of slope angle, porosity, and a number of walls on wave energy dissipation for a wide range of random and regular waves. The results of this study can be used to improve and optimize energy dissipation and reduce construction cost.

Keywords: porosity, slope, wave reflection, wave transmission

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97 Some Specialized Prosaic Arts of the Ancient Arabic Literature; An Introductory Analysis

Authors: Shams Ul Hussain Zaheer, Bakht Rahman, Shehla Shams, Bibi Alia

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Arabic literature, from the very past, is divided into two basic parts: prose and poetry. It will not be wrong if it is said that this division of literature is found even in the era of ignorance (before-Islam). In this period, prose was given a kind of ignorance while poetry was given much significance since people showed deeper interest in its melodious impact while listening and singing as compared to prose writing. Because poetry was directly appealing to the emotions of the people, it was celebrated as universal genre and prose remained in a subordinate position due to its diction. Despite this attitude towards the genre of prose, some of the prosaic arts were orally transmitted from one generation to another during the era of ignorance. Later on, in the Omayyad and Abbasside periods, when literature was properly classified, this art was given its proper placement in the history. In this connection, there are three important aspects of this genre i.e. will, tales, and sacerdotal words. This paper traces the historical background of these categories and how they contributed to the modern understanding of literature in terms of its diction, themes, and kinds of prose writing. This is a descriptive and qualitative research which will add insight into the role these terms can play in understanding the thinking and inclination of people in the days of ignorance.

Keywords: Arabic literature, era of ignorance, prose, special arts, analysis

Procedia PDF Downloads 67
96 Fuzzy Multi-Criteria Decision-Making Based on Ignatian Discernment Process

Authors: Pathinathan Theresanathan, Ajay Minj

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Ignatian Discernment Process (IDP) is an intense decision-making tool to decide on life-issues. Decisions are influenced by various factors outside of the decision maker and inclination within. This paper develops IDP in the context of Fuzzy Multi-criteria Decision Making (FMCDM) process. Extended VIKOR method is a decision-making method which encompasses even conflict situations and accommodates weightage to various issues. Various aspects of IDP, namely three ways of decision making and tactics of inner desires, are observed, analyzed and articulated within the frame work of fuzzy rules. The decision-making situations are broadly categorized into two types. The issues outside of the decision maker influence the person. The inner feeling also plays vital role in coming to a conclusion. IDP integrates both the categories using Extended VIKOR method. Case studies are carried out and analyzed with FMCDM process. Finally, IDP is verified with an illustrative case study and results are interpreted. A confused person who could not come to a conclusion is able to take decision on a concrete way of life through IDP. The proposed IDP model recommends an integrated and committed approach to value-based decision making.

Keywords: AHP, FMCDM, IDP, ignatian discernment, MCDM, VIKOR

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95 Clothing and Personnel Selection: An Experimental Study to Test the Effects of Dress Style on Hirability Perceptions

Authors: Janneke K. Oostrom, Richard Ronay

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The so called “red sneakers effect” refers to people’s inclination to infer status and competence from signals of nonconformity. In the current research, we explore an untested possible boundary condition to the red sneakers effect within the context of personnel selection. In two experimental studies (total N = 156), we examined how (non)conforming dress style interacts with the quality of a job applicant’s resume to determine hirability perceptions. We found that dress style indeed impacts hirability perceptions, but that the exact impact depends on the quality of the applicant’s resume. Results revealed that applicants with a low quality resume were punished for behaving in a nonconforming way, whereas applicants with a high quality resume appeared to have the leeway to dress as they please. Importantly, the observed interaction effect was mediated by perceptions of power. These findings suggest that nonconforming dress acts as a power-signaling mechanism in the context of personnel selection. However, the signaling effects of non-conforming dress style can backfire when accompanied by evidence that such posturing is not matched by cues of actual competence.

Keywords: clothing, hirability, nonconformity, personnel selection, power

Procedia PDF Downloads 153
94 Investigation of Several Parameters on Local Scour around Inclined Dual Bridge Piers

Authors: Murat Çeşme

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For a bridge engineer to ensure a safe footing design, it is very important to estimate the maximum scour depth around the piers as accurately as possible. Many experimental studies have been performed by several investigators to obtain information about scouring mechanism. In order to examine the effect of inclination of dual bridge piers on scour depth under clear-water conditions for various uniform flow depths, an experimental research on scaled dual bridge piers has been carried over in METU Hydromechanics Lab. Dimensional and non-dimensional curves were developed and presented to show the variation of scour depth with respect to various parameters such as footing angle with the vertical, flow depth and footing dimensions. Results of the study were compared to those obtained from a similar study performed with single inclined piers to see the effect of the second pier on scour depths. Useful equations for the design engineers were developed based on multiple regression analyses to be used for predicting local scour depths around inclined piers in uniform and non-uniform sediments.

Keywords: experimental research, inclined dual bridge piers, footing safety, scour depth, clear water condition

Procedia PDF Downloads 75
93 Solar Still Absorber Plate Modification and Exergy Analysis

Authors: Dudul Das, Pankaj Kalita, Sangeeta Borah

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Freshwater availability in the world is as low as 1% of total water available and in many geographical locations dissolved fluoride and arsenic are serious problem. In India availability of freshwater will be stressed by 2025, so the availability saline water from sea is a hope for the people of Indian sub-continent, but saline water is not drinkable it need to be processed, which again require a huge amount of energy. So the most easy and handy option in such situation for all those problems is solar still, this investigation presents various scopes for improvement of its efficiency. Experiments showed that by increasing the absorber plate area through better design can increase the distillate output by two fold and by using jute wicks in the modified absorber plate increases the output up to three times that of conventional solar still available in the Department of Energy, Tezpur University. The experiment is carried out at constant water depth of 8.5 cm and glass cover inclination of 27o facing South. The exergy analysis carried out clearly resulted that with the use of jute wick and baffle plated basin the efficiency achieved more than the simple baffle plated basin. The Instantaneous exergy without jute wick ranges from 2.5% to 4.5% while using jute it ranges from 1.5% to 5.15%.

Keywords: fluoride, absorber plate, jute wick, instantaneous exergy

Procedia PDF Downloads 436
92 REDD+ and Conservation: Challenges and Opportunities of the Landscape Governance Approach

Authors: Richard Mbatu

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Implementation of the Reducing Emissions from Deforestation and forest Degradation (REDD+) program will not only lead to significant net gains in greenhouse gas reduction but also gains in biodiversity conservation. However, the looming paradigm shift in the program in the form of the proposed landscape governance approach could change this inclination. The concern lies with the fact that pursue of carbon credits by governments and private entities under the proposed landscape approach could encourage obstinate land use behaviors that are detrimental to the cause of biodiversity conservation and ecosystem services. Yet, the landscape approach could also stimulate governments to develop and implement land use management policies for climate change adaptation and mitigation. Using two potential areas of land use under the proposed landscape approach – carbon farming in grasslands and carbon farming in plantations – this paper provides a balanced analytical review of conservation challenges and opportunities for forest governance and beyond under the proposed landscape approach to REDD+. The paper argues that such a balanced view will enable policymakers and other stakeholders to better present their arguments in their efforts to shape the course of the REDD+ program in the post-Paris Agreement era.

Keywords: biodiversity conservation, REDD+, forest governance, grasslands, landscape approach, plantations

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91 Using Tilted Façade to Reduce Thermal Discomfort in a UK Passivhaus Dwelling for a Warming Climate

Authors: Yahya Lavafpour, Steve Sharples

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This study investigated the potential negative impacts of future UK climate change on dwellings. In particular, the risk of overheating was considered for a Passivhaus dwelling in London. The study used dynamic simulation modelling software to investigate the potential use of building geometry to control current and future overheating risks in the dwelling for London climate. Specifically, the focus was on the optimum inclination of a south façade to make use of the building’s shape to self-protect itself. A range of different inclined façades were examined to test their effectiveness in reducing the overheating risk. The research found that implementing a 115° tilted façade could completely eliminate the risk of overheating in current climate, but with some consequence for natural ventilation and daylighting. Future overheating was significantly reduced by the tilted façade. However, geometric considerations could not eradicate completely the risk of overheating particularly by the 2080s. The study also used CFD modelling and sensitivity analysis to investigate the effect of the façade geometry on the wind pressure distributions on and around the building surface. This was done to assess natural ventilation flows for alternative façade inclinations.

Keywords: climate change, tilt façade, thermal comfort, passivhaus, overheating

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90 Quadratic Convective Flow of a Micropolar Fluid in a Non-Darcy Porous Medium with Convective Boundary Condition

Authors: Ch. Ramreddy, P. Naveen, D. Srinivasacharya

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The objective of the present study is to investigate the effect of nonlinear temperature and concentration on the mixed convective flow of micropolar fluid over an inclined flat plate in a non-Darcy porous medium in the presence of convective boundary condition. In order to analyze all the essential features, the transformed nonlinear conservation equations are worked out numerically by spectral method. By insisting the comparison between vertical, horizontal and inclined plates, the physical quantities of the flow and its characteristics are exhibited graphically and quantitatively with various parameters. An increase in the coupling number and inclination of angle tend to decrease the skin friction, mass transfer rate and the reverse change is there in wall couple stress and heat transfer rate. The nominal effect on the wall couple stress and skin friction is encountered whereas the significant effect on the local heat and mass transfer rates are found for high enough values of Biot number.

Keywords: convective boundary condition, micropolar fluid, non-darcy porous medium, non-linear convection, spectral method

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89 Explanation of the Electron Transfer Mechanism from β-Carotene to N-Pentyl Peroxyl Radical by Density Functional Theory Method

Authors: E. Esra Kasapbaşı, Büşra Yıldırım

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Weak oxidizing radicals, such as alkyl peroxyl derivatives, react with carotenoids through hydrogen atom transfer to form neutral carotenoid radicals. Using the DFT method, it has been observed that s-cis-β-carotene is more stable than all-transforms. In the context of this study, an attempt is made to explain the reaction mechanism of the isomers of β-carotene, which exhibits antioxidant properties, with n-pentyl peroxide, one of the alkyl peroxyl molecules, using the Density Functional Theory (DFT) method. The cis and transforms of β-carotene are used in the study to determine which form is more reactive. For this purpose, Natural Bond Orbital (NBO) charges of all optimized structures are calculated, and electron transfer is determined by examining electron transitions between Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). Additionally, the radical character and reaction mechanism of β-carotene in a radical environment are attempted to be explained based on the calculations. The theoretical inclination of whether β-carotene in cis or transforms is more active in reaction is also discussed. All these calculations are performed in the gas phase using the Integral Equation Formalism Polarizable Continuum Model IEFPCM method with dichloromethane as the solvent.

Keywords: β-carotene, n-pentyl peroxyl radical, DFT, TD-DFT

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88 Heat Transfer Enhancement Due to the Optimal Porosity in Plate Heat Exchangers with Sinusoidal Plates

Authors: Hossein Shokouhmand, Seyyed Mostafa Saadat

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In this paper, the effect of thermal dispersion on the performance of plate heat exchangers (PHEs) with sinusoidal plates is investigated. In this regard, the PHE is considered as a porous medium. The important property of a porous medium is porosity that is defined as the total fluid volume divided by the total volume occupied by the solid and fluid. A 2D array of parallel sinusoidal plates with laminar periodically developed forced convection and single-phase constant property flows and conduction in a homogenous solid phase in two directions is considered. The array of flows is counter and the flows heat capacities are equal. Numerical study of conjugate heat transfer and axial conduction in the solid phase with different plate thicknesses showed that there is an optimal porosity in which the efficiency of heat transfer is up to 4% more than the time when the porosity is near one. It is shown that the optimal porosity at zero angle of inclination depends both on Reynolds number and the aspect ratio. The optimal porosity increased while either the Reynolds number or waviness of plates increased.

Keywords: plate heat exchanger, optimal porosity, efficiency, aspect ratio

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87 Analysis of the Effect of Food Veils on the Preservation of Button and Oyster Mushrooms, Case Study: Zein Corn Coating

Authors: Mohamad Javad Shakouri, Hamid Tavakkolipour, Mahdis Jamshidi Tehranian

Abstract:

The inclination toward using food coatings is increasing daily, due to containing natural elements and not producing environmental pollution. Food coatings are uniform and thin layers of natural substances that cover the food product and act as a barrier against moisture, oxygen, and substances dissolved in food. Using food coatings on fruits and vegetables can delay water dissipation, losing aroma, decolorization, and improve the appearance of the product, and in general, preserve and protect the quality of fresh produce. When fruits and vegetables grow, they are equipped with a natural shield, called cuticle– a layer of wax. Washing the products, after harvest, the cuticle – this protective coating – is removed. In order to replace the cuticle, we can use an edible protective coating. This coating delays dehydration and deterioration and hence increases the life of the product while keeping its moisture. In this study, it was concluded that using food coatings, such as corn zein, carrageenan, and starch can have a substantial effect on the quantitative and qualitative preservation of food products, such as fruits, vegetables, and mushrooms.

Keywords: food coating, corn zein, button and oyster mushrooms, ascorbic and citric acids

Procedia PDF Downloads 271
86 Numerical Analysis and Influence of the Parameters on Slope Stability

Authors: Fahim Kahlouche, Alaoua Bouaicha, Sihem Chaîbeddra, Sid-Ali Rafa, Abdelhamid Benouali

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A designing of a structure requires its realization on rough or sloping ground. Besides the problem of the stability of the landslide, the behavior of the foundations that are bearing the structure is influenced by the destabilizing effect of the ground’s slope. This article focuses on the analysis of the slope stability exposed to loading by introducing the different factors influencing the slope’s behavior on the one hand, and on the influence of this slope on the foundation’s behavior on the other hand. This study is about the elastoplastic modelization using FLAC 2D. This software is based on the finite difference method, which is one of the older methods of numeric resolution of differential equations system with initial and boundary conditions. It was developed for the geotechnical simulation calculation. The aim of this simulation is to demonstrate the notable effect of shear modulus « G », cohesion « C », inclination angle (edge) « β », and distance between the foundation and the head of the slope on the stability of the slope as well as the stability of the foundation. In our simulation, the slope is constituted by homogenous ground. The foundation is considered as rigid/hard; therefore, the loading is made by the application of the vertical strengths on the nodes which represent the contact between the foundation and the ground. 

Keywords: slope, shallow foundation, numeric method, FLAC 2D

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85 Curriculum Change and Innovation Viewed from Two Different Lenses

Authors: Muqaddas Butt, Allah Bakhsh Malik

Abstract:

The changing educational environment, the diverse educational needs of students, the high expectations from the public, and the policy reports demand a strong change & innovation in the curriculum. Effective change and innovation could not be possible without the involvement of two major tenants i.e. teachers and educational managers. Thus, the locus of this research was to explore the secondary school principals and teachers priorities regarding change and innovation in curriculum. The main research objectives were included to explore the secondary school teachers’ and principals’ views about existing Humanities group curriculum; to identify their priorities regarding change and innovation in curriculum and to make a comparison between the priorities of both (the teachers & principals). A total sample of 150 Secondary school teachers and 24 principals from Federal Government Secondary Schools was drawn. The data was obtained through a five point Likert scale questionnaire. The findings indicated a huge difference between principals and teachers priorities. Related to prevailed curriculum, teachers showed more satisfactory views than principals. It was also found that the principals in comparison with teachers showed more inclination towards change and innovation and emphasized on an interdisciplinary, practical and ICT Integrated curriculum. Inclusion of local environmental issues; creativity based and practical activities based curriculum; and orientation to citizenship education into curriculum were some of the aspects highly prioritized by both teachers and principals.

Keywords: curriculum change, curriculum innovation, humanities curriculum, curriculum priorities

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84 Evaluation Practices in Colombia: Between Beliefs and National Exams

Authors: Danilsa Lorduy, Liliana Valle

Abstract:

Assessment and evaluation are inextricable parts of the teaching learning process. Evaluation practices concerns are gaining popularity among curriculum developers an educational researchers, particularly in Colombian regions where English language is taught as a foreign language EFL. This study addressed one of those issues, which are the unbalanced in –services’ evaluation practices perceived in school classes. They present predominance on the written test among the procedures they use to evaluate; therefore, the purpose of this case study was to explore in-service teachers’ evaluation practices, their beliefs about evaluation and to establish an eventual connection between practices and beliefs. To this end, classroom observations, questionnaires, and a semi structured interview were applied to three in-service English teachers from different schools in a city in Colombia. The findings suggested that teachers’ beliefs indicate a formative inclination and they actually are using a variety of procedures different from test but they seem to have some issues regarding their appropriateness for application Moreover, it was found that teachers’ practices are being influenced by external factors such as school requirements and national policies. It could be concluded that the predominance in using tests is not only elicited by teachers’ beliefs but also by national test results 'Pruebas Saber' and law 115 demanding. It was also suggested that further quantitative research is needed to demonstrate connections between overuse of testing procedures and 'Pruebas Saber' national test.

Keywords: beliefs, evaluation, external factors, national test

Procedia PDF Downloads 143