Search results for: critical cancer
3619 Algerian Case Study of Age Effect and Cross Linguistic Influence in Third Language Phonology Acquisition
Authors: Zouleykha Belabbes
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Learning foreign languages is sine qua non in the era of globalization, mobility, and communications, which grants access and connectedness to the world. This urgent need is highlighted in monolingual settings, however, in multilingual contexts the case is, to some extent, complicated. In effect, research on bilingualism and multilingualism lead to the issue of Cross Linguistic Influence (CLI) which seeks to explain how and under which conditions prior linguistic knowledge of first language (L1) and / or second language (L2) influences the production, comprehension and development of a third language (L3) or additional language (Ln). Moreover, the issue of age is also one of the persistent topics in the field of language acquisition. This paper aims to scrutinize the effect of age and two previously known languages: Arabic (L1) and French (L2) in acquiring English (L3) phonology in Algerian context. The study consisted of 20 participants of different age range who were presented with recorded samples of English (L3). The findings confirm the results of some previous studies on the issue of Critical Period Hypothesis (CPH) and demonstrate a tendency for the L2 phonological transfer in L3 production at the initial stages of acquisition within young and later learners that for some circumstances diminished as L3 proficiency develop.Keywords: acquisition, age effect, cross linguistic influence, L3 phonology
Procedia PDF Downloads 2313618 Real-Time Recognition of the Terrain Configuration to Improve Driving Stability for Unmanned Robots
Authors: Bongsoo Jeon, Jayoung Kim, Jihong Lee
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Methods for measuring or estimating of ground shape by a laser range finder and a vision sensor (exteroceptive sensors) have critical weakness in terms that these methods need prior database built to distinguish acquired data as unique surface condition for driving. Also, ground information by exteroceptive sensors does not reflect the deflection of ground surface caused by the movement of UGVs. Therefore, this paper proposes a method of recognizing exact and precise ground shape using Inertial Measurement Unit (IMU) as a proprioceptive sensor. In this paper, firstly this method recognizes attitude of a robot in real-time using IMU and compensates attitude data of a robot with angle errors through analysis of vehicle dynamics. This method is verified by outdoor driving experiments of a real mobile robot.Keywords: inertial measurement unit, laser range finder, real-time recognition of the ground shape, proprioceptive sensor
Procedia PDF Downloads 2823617 Nanomaterial Based Electrochemical Sensors for Endocrine Disrupting Compounds
Authors: Gaurav Bhanjana, Ganga Ram Chaudhary, Sandeep Kumar, Neeraj Dilbaghi
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Main sources of endocrine disrupting compounds in the ecosystem are hormones, pesticides, phthalates, flame retardants, dioxins, personal-care products, coplanar polychlorinated biphenyls (PCBs), bisphenol A, and parabens. These endocrine disrupting compounds are responsible for learning disabilities, brain development problems, deformations of the body, cancer, reproductive abnormalities in females and decreased sperm count in human males. Although discharge of these chemical compounds into the environment cannot be stopped, yet their amount can be retarded through proper evaluation and detection techniques. The available techniques for determination of these endocrine disrupting compounds mainly include high performance liquid chromatography (HPLC), mass spectroscopy (MS) and gas chromatography-mass spectrometry (GC–MS). These techniques are accurate and reliable but have certain limitations like need of skilled personnel, time consuming, interference and requirement of pretreatment steps. Moreover, these techniques are laboratory bound and sample is required in large amount for analysis. In view of above facts, new methods for detection of endocrine disrupting compounds should be devised that promise high specificity, ultra sensitivity, cost effective, efficient and easy-to-operate procedure. Nowadays, electrochemical sensors/biosensors modified with nanomaterials are gaining high attention among researchers. Bioelement present in this system makes the developed sensors selective towards analyte of interest. Nanomaterials provide large surface area, high electron communication feature, enhanced catalytic activity and possibilities of chemical modifications. In most of the cases, nanomaterials also serve as an electron mediator or electrocatalyst for some analytes.Keywords: electrochemical, endocrine disruptors, microscopy, nanoparticles, sensors
Procedia PDF Downloads 2703616 The Impact of Social Enterprises on Women Empowerment in South Asia: A Systematic Review
Authors: Saba Aziz
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Social enterprises are playing a growing role in transforming the lives of individuals and communities around the world, providing innovative solutions to critical social and environmental issues such as education, job creation, and health care. Women are increasingly utilising services of these enterprises to overcome socio-economic constraints and increase their access to business and market. This article systematically reviews the available literature on the role of social enterprises on women's empowerment in South Asia. Twelve key terms were specified and researched on five databases. Some of the literature was excluded based on the lack of evidence on the involvement of social enterprises. Remaining literature was rated according to the quality; due to methodological inconsistency, the findings are presented in a descriptive form. The relevant studies review the impact of social enterprises on women’s economic, social, relational, health, personal and political aspects of empowerment. In discussion, we outline areas for further research on social enterprises activity that impacts women’s overall empowerment specifically in South Asia.Keywords: social enterprise, women empowerment, systematic review, well-being, social impact, micro finance, South Asia, Pakistan
Procedia PDF Downloads 1613615 Investigations into Effect of Neural Network Predictive Control of UPFC for Improving Transient Stability Performance of Multimachine Power System
Authors: Sheela Tiwari, R. Naresh, R. Jha
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The paper presents an investigation into the effect of neural network predictive control of UPFC on the transient stability performance of a multi-machine power system. The proposed controller consists of a neural network model of the test system. This model is used to predict the future control inputs using the damped Gauss-Newton method which employs ‘backtracking’ as the line search method for step selection. The benchmark 2 area, 4 machine system that mimics the behavior of large power systems is taken as the test system for the study and is subjected to three phase short circuit faults at different locations over a wide range of operating conditions. The simulation results clearly establish the robustness of the proposed controller to the fault location, an increase in the critical clearing time for the circuit breakers and an improved damping of the power oscillations as compared to the conventional PI controller.Keywords: identification, neural networks, predictive control, transient stability, UPFC
Procedia PDF Downloads 3663614 Influence of Measurement System on Negative Bias Temperature Instability Characterization: Fast BTI vs Conventional BTI vs Fast Wafer Level Reliability
Authors: Vincent King Soon Wong, Hong Seng Ng, Florinna Sim
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Negative Bias Temperature Instability (NBTI) is one of the critical degradation mechanisms in semiconductor device reliability that causes shift in the threshold voltage (Vth). However, thorough understanding of this reliability failure mechanism is still unachievable due to a recovery characteristic known as NBTI recovery. This paper will demonstrate the severity of NBTI recovery as well as one of the effective methods used to mitigate, which is the minimization of measurement system delays. Comparison was done in between two measurement systems that have significant differences in measurement delays to show how NBTI recovery causes result deviations and how fast measurement systems can mitigate NBTI recovery. Another method to minimize NBTI recovery without the influence of measurement system known as Fast Wafer Level Reliability (FWLR) NBTI was also done to be used as reference.Keywords: fast vs slow BTI, fast wafer level reliability (FWLR), negative bias temperature instability (NBTI), NBTI measurement system, metal-oxide-semiconductor field-effect transistor (MOSFET), NBTI recovery, reliability
Procedia PDF Downloads 4153613 Simplifying the Migration of Architectures in Embedded Applications Introducing a Pattern Language to Support the Workforce
Authors: Farha Lakhani, Michael J. Pont
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There are two main architectures used to develop software for modern embedded systems: these can be labelled as “event-triggered” (ET) and “time-triggered” (TT). The research presented in this paper is concerned with the issues involved in migration between these two architectures. Although TT architectures are widely used in safety-critical applications they are less familiar to developers of mainstream embedded systems. The research presented in this paper began from the premise that–for a broad class of systems that have been implemented using an ET architecture–migration to a TT architecture would improve reliability. It may be tempting to assume that conversion between ET and TT designs will simply involve converting all event-handling software routines into periodic activities. However, the required changes to the software architecture are, in many cases rather more profound. The main contribution of the work presented in this paper is to identify ways in which the significant effort involved in migrating between existing ET architectures and “equivalent” (and effective) TT architectures could be reduced. The research described in this paper has taken an innovative step in this regard by introducing the use of ‘Design patterns’ for this purpose for the first time.Keywords: embedded applications, software architectures, reliability, pattern
Procedia PDF Downloads 3213612 Dynamic Reroute Modeling for Emergency Evacuation: Case Study of Brunswick City, Germany
Authors: Yun-Pang Flötteröd, Jakob Erdmann
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The human behaviors during evacuations are quite complex. One of the critical behaviors which affect the efficiency of evacuation is route choice. Therefore, the respective simulation modeling work needs to function properly. In this paper, Simulation of Urban Mobility’s (SUMO) current dynamic route modeling during evacuation, i.e. the rerouting functions, is examined with a real case study. The result consistency of the simulation and the reality is checked as well. Four influence factors (1) time to get information, (2) probability to cancel a trip, (3) probability to use navigation equipment, and (4) rerouting and information updating period are considered to analyze possible traffic impacts during the evacuation and to examine the rerouting functions in SUMO. Furthermore, some behavioral characters of the case study are analyzed with use of the corresponding detector data and applied in the simulation. The experiment results show that the dynamic route modeling in SUMO can deal with the proposed scenarios properly. Some issues and function needs related to route choice are discussed and further improvements are suggested.Keywords: evacuation, microscopic traffic simulation, rerouting, SUMO
Procedia PDF Downloads 1863611 The Study of Sensory Breadth Experiences in an Online Try-On Environment
Authors: Tseng-Lung Huang
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Sensory breadth experiences, such as visualization, a sense of self-location, and haptic experiences, are critical in an online try-on environment. This research adopts an emotional appeal perspective, including concrete and abstract effects, to clarify the relationship between sensory experience and consumer's behavior intention in an online try-on context. This study employed an augmented reality interactive technology (ARIT) in an online clothes-fitting context and applied snowball sampling using e-mail to invite online consumers, first to use ARIT for trying on online apparel and then to complete a questionnaire. One hundred sixty-eight valid questionnaires were collected, and partial least squares (PLS) path modeling was used to test our hypotheses. The results showed that sensory breadth, by arousing concrete effect, induces impulse buying intention and willingness to pay a price premium of online shopping. Parasocial presence, as an abstract effect, diminishes the effect of concrete effects on willingness to pay a price premium.Keywords: sensory breadth, impulsive behavior, price premium, emotional appeal, online try-on context
Procedia PDF Downloads 5413610 Phenolic Composition and Antioxidant Property of Honey with Dried Apricots
Authors: Jasna Čanadanović-Brunet, Gordana Ćetković, Sonja Djilas, Vesna Tumbas-Šaponjac, Jelena Vulić, Sladjana Stajčić
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Honey, produced by the honeybee, is a natural saturated sugar solution, which is mainly composed of a complex mixture of carbohydrates. Besides this, it also contains certain minor constituents, proteins, enzymes, amino and organic acids, lipids, vitamins, phenolic acids, flavonoids and carotenoids. Honey serves as a source of natural antioxidants, which are effective in reducing the risk of heart disease, cancer, immune-system decline, cataracts, and different inflammatory processes. Honey is consumed in its natural form alone, but also in combination with nuts and various kinds of dried fruits (plums, figs, cranberries, apricots etc.). The aim of this research was to investigate the contribution of dried apricot addition to polyphenols and flavonoids contents and antioxidant activities of honey. Some individual phenolic compounds in Serbian polyfloral honey (PH), linden honey (LH) and also in their mixtures with dried apricot, in 40% mass concentrations (PH40; LH40), were identified and quantified by HPLC. The most dominant phenolic compound was: gallic acid in LH (11.14 mg/100g), LH40 (42.65 mg/100g), PH (7.24 mg/100g) and catehin in PH40 (11.83 mg/100g). The antioxidant activity of PH, LH, PH40 and LH40 was tested by measuring their ability to scavenge hydroxyl radicals (OH) by electron spin resonance spectroscopy (ESR). Honey samples with 40% dried apricot exhibited better antioxidant activity measured by hydroxyl radical scavenging activity. The EC50 values, the amount of antioxidant necessary to decrease the initial concentration of OH radicals by 50%, were: EC50PH=3.36 mg/ml, EC50LH=13.36 mg/ml, EC50PH40=2.29 mg/ml, EC50 LH40=7.78 mg/ml. Our results indicate that supplementation of polyfloral honey and linden honey with dried apricots improves antioxidant activity of honey by enriching the phenolic composition.Keywords: honey, dried apricot, HPLC, hydroxyl radical
Procedia PDF Downloads 3493609 Magnesium Alloys Containing Y, Gd and Ca with Enhanced Ignition Temperature and Mechanical Properties for Aviation Applications
Authors: Jiří Kubásek, Peter Minárik, Klára Hosová, Stanislav Šašek, Jozef Veselý, Jitka Stráská, Drahomír Dvorský, Dalibor Vojtěch, Miloš Janeček
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Mg-2Y-2Gd-1Ca and Mg-4Y-4Gd-2Ca alloys were processed by extrusion or equal channel angular pressing (ECAP) to analyse the effect of the microstructure on ignition temperature, mechanical properties and corrosion resistance. The alloys are characterized by good mechanical properties and exceptionally high ignition temperature, which is a critical safety measure. The effect of extrusion and ECAP on the microstructure, mechanical properties and ignition temperature was studied. The obtained results indicated a substantial effect of the processing conditions on the average grain size, the recrystallized fraction and texture formation. Both alloys featured a high strength, depending on the composition and processing condition, and a high ignition temperature of ≈1100 °C (Mg-4Y-4Gd-2Ca) and ≈950 °C (Mg-2Y-2Gd-1Ca), which was attributed to the synergic effect of Y, Gd and Ca oxides, with the dominant effect of Y₂O₃. The achieved combination of enhanced mechanical properties and the ignition temperature makes these alloys a prominent candidate for aircraft applications.Keywords: magnesium alloys, enhanced ignition temperature, mechanical properties, ECAP
Procedia PDF Downloads 953608 LES Investigation of the Natural Vortex Length in a Small-Scale Gas Cyclone
Authors: Dzmitry Misiulia, Sergiy Antonyuk
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Small-scale cyclone separators are widely used in aerosol sampling. The flow field in a cyclone sampler is very complex, especially the vortex behavior. Most of the existing models for calculating cyclone efficiency use the same stable vortex structure while the vortex demonstrates dynamic variations rather than the steady-state picture. It can spontaneously ‘end’ at some point within the body of the separator. Natural vortex length is one of the most critical issues when designing and operating gas cyclones and is crucial to proper cyclone performance. The particle transport along the wall to the grid pot is not effective beyond this point. The flow field and vortex behavior inside the aerosol sampler have been investigated for a wide range of Reynolds numbers using Large Eddy Simulations. Two characteristics types of vortex behavior have been found with simulations. At low flow rates the vortex created in the cyclone dissipates in free space (without attaching to a surface) while at higher flow rates it attaches to the cyclone wall. The effects of the Reynolds number on the natural vortex length and the rotation frequency of the end of the vortex have been revealed.Keywords: cyclone, flow field, natural vortex length, pressure drop
Procedia PDF Downloads 1483607 An Approach to Make an Adaptive Immunoassay to Detect an Unknown Disease
Authors: Josselyn Mata Calidonio, Arianna I. Maddox, Kimberly Hamad-Schifferli
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Rapid diagnostics are critical infectious disease tools that are designed to detect a known biomarker using antibodies specific to that biomarker. However, a way to detect unknown viruses has not yet been achieved in a paper test format. We describe here a route to make an adaptable paper immunoassay that can detect an unknown biomarker, demonstrating it on SARS-CoV-2 variants. The immunoassay repurposes cross-reactive antibodies raised against the alpha variant. Gold nanoparticles of two different colors conjugated to two different antibodies create a colorimetric signal, and machine learning of the resulting colorimetric pattern is used to train the assay to discriminate between variants of alpha and Omicron BA.5. By using principal component analysis, the colorimetric test patterns can pick up and discriminate an unknown that it has not encountered before, Omicron BA.1. The test has an accuracy of 100% and a potential calculated discriminatory power of 900. We show that it can be used adaptively and that it can be used to pick up emerging variants without the need to raise new antibodies.Keywords: adaptive immunoassay, detecting unknown viruses, gold nanoparticles, paper immunoassay, repurposing antibodies
Procedia PDF Downloads 1033606 Building an Integrated Relational Database from Swiss Nutrition National Survey and Swiss Health Datasets for Data Mining Purposes
Authors: Ilona Mewes, Helena Jenzer, Farshideh Einsele
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Objective: The objective of the study was to integrate two big databases from Swiss nutrition national survey (menuCH) and Swiss health national survey 2012 for data mining purposes. Each database has a demographic base data. An integrated Swiss database is built to later discover critical food consumption patterns linked with lifestyle diseases known to be strongly tied with food consumption. Design: Swiss nutrition national survey (menuCH) with approx. 2000 respondents from two different surveys, one by Phone and the other by questionnaire along with Swiss health national survey 2012 with 21500 respondents were pre-processed, cleaned and finally integrated to a unique relational database. Results: The result of this study is an integrated relational database from the Swiss nutritional and health databases.Keywords: health informatics, data mining, nutritional and health databases, nutritional and chronical databases
Procedia PDF Downloads 1053605 Disablism in Saudi Mainstream Schools: Disabled Teachers’ Experiences and Perspectives
Authors: Ali Aldakhil
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This paper explores the many faces of the barriers and exclusionary attitudes and practices that disabled teachers and students experience in a school where they teach or attend. Critical disability studies and inclusive education theory were used to conceptualise this inquiry and ground it in the literature. These theories were used because they magnify and expose the problems of disability/disablism as within-society instead of within-individual. Similarly, disability-first language was used in this study because it seeks to expose the social oppression and discrimination of disabled. Data were generated through conducting in-depth semi-structured interviews with six disabled teachers who teach disabled children in a Saudi mainstream school. Thematic analysis of data concludes that the school is fettered by disabling barriers, attitudes, and practices, which reflect the dominant culture of disablism that disabled people encounter in the Saudi society on a daily basis. This leads to the conclusion that overall deconstruction and reformation of Saudi mainstream schools are needed, including non-disabled people’s attitudes, policy, spaces, and overall arrangements of teaching and learning.Keywords: disablism, disability studies, mainstream schools, Saudi Arabia
Procedia PDF Downloads 1513604 Bridging Educational Research and Policymaking: The Development of Educational Think Tank in China
Authors: Yumei Han, Ling Li, Naiqing Song, Xiaoping Yang, Yuping Han
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Educational think tank is agreeably regarded as significant part of a nation’s soft power to promote the scientific and democratic level of educational policy making, and it plays critical role of bridging educational research in higher institutions and educational policy making. This study explores the concept, functions and significance of educational think tank in China, and conceptualizes a three dimensional framework to analyze the approaches of transforming research-based higher institutions into effective educational think tanks to serve educational policy making in the nation wide. Since 2014, the Ministry of Education P.R. China has been promoting the strategy of developing new type of educational think tanks in higher institutions, and such a strategy has been put into the agenda for the 13th Five Year Plan for National Education Development released in 2017.In such context, increasing scholars conduct studies to put forth strategies of promoting the development and transformation of new educational think tanks to serve educational policy making process. Based on literature synthesis, policy text analysis, and analysis of theories about policy making process and relationship between educational research and policy-making, this study constructed a three dimensional conceptual framework to address the following questions: (a) what are the new features of educational think tanks in the new era comparing traditional think tanks, (b) what are the functional objectives of the new educational think tanks, (c) what are the organizational patterns and mechanism of the new educational think tanks, (d) in what approaches traditional research-based higher institutions can be developed or transformed into think tanks to effectively serve the educational policy making process. The authors adopted case study approach on five influential education policy study centers affiliated with top higher institutions in China and applied the three dimensional conceptual framework to analyze their functional objectives, organizational patterns as well as their academic pathways that researchers use to contribute to the development of think tanks to serve education policy making process.Data was mainly collected through interviews with center administrators, leading researchers and academic leaders in the institutions. Findings show that: (a) higher institution based think tanks mainly function for multi-level objectives, providing evidence, theoretical foundations, strategies, or evaluation feedbacks for critical problem solving or policy-making on the national, provincial, and city/county level; (b) higher institution based think tanks organize various types of research programs for different time spans to serve different phases of policy planning, decision making, and policy implementation; (c) in order to transform research-based higher institutions into educational think tanks, the institutions must promote paradigm shift that promotes issue-oriented field studies, large data mining and analysis, empirical studies, and trans-disciplinary research collaborations; and (d) the five cases showed distinguished features in their way of constructing think tanks, and yet they also exposed obstacles and challenges such as independency of the think tanks, the discourse shift from academic papers to consultancy report for policy makers, weakness in empirical research methods, lack of experience in trans-disciplinary collaboration. The authors finally put forth implications for think tank construction in China and abroad.Keywords: education policy-making, educational research, educational think tank, higher institution
Procedia PDF Downloads 1543603 Economical Analysis of Optimum Insulation Thickness for HVAC Duct
Authors: D. Kumar, S. Kumar, A. G. Memon, R. A. Memon, K. Harijan
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A considerable amount of energy is usually lost due to compression of insulation in Heating, ventilation, and air conditioning (HVAC) duct. In this paper, the economic impact of compression of insulation is estimated. Relevant mathematical models were used to estimate the optimal thickness at the points of compression. Furthermore, the payback period is calculated for the optimal thickness at the critical parts of supply air duct (SAD) and return air duct (RAD) considering natural gas (NG) and liquefied petroleum gas (LPG) as fuels for chillier operation. The mathematical model is developed using preliminary data obtained for an HVAC system of a pharmaceutical company. The higher heat gain and cooling loss, due to compression of thermal insulation, is estimated using relevant heat transfer equations. The results reveal that maximum energy savings (ES) in SAD is 34.5 and 40%, while in RAD is 22.9% and 29% for NG and LPG, respectively. Moreover, the minimum payback period (PP) for SAD is 2 and 1.6years, while in RAD is 4.3 and 2.7years for NG and LPG, respectively. The optimum insulation thickness (OIT) corresponding to maximum ES and minimum PP is estimated to be 35 and 42mm for SAD, while 30 and 38mm for RAD in case of NG and LPG, respectively.Keywords: optimum insulation thickness, life cycle cost analysis, payback period, HVAC system
Procedia PDF Downloads 2093602 Determining the Most Efficient Test Available in Software Testing
Authors: Qasim Zafar, Matthew Anderson, Esteban Garcia, Steven Drager
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Software failures can present an enormous detriment to people's lives and cost millions of dollars to repair when they are unexpectedly encountered in the wild. Despite a significant portion of the software development lifecycle and resources are dedicated to testing, software failures are a relatively frequent occurrence. Nevertheless, the evaluation of testing effectiveness remains at the forefront of ensuring high-quality software and software metrics play a critical role in providing valuable insights into quantifiable objectives to assess the level of assurance and confidence in the system. As the selection of appropriate metrics can be an arduous process, the goal of this paper is to shed light on the significance of software metrics by examining a range of testing techniques and metrics as well as identifying key areas for improvement. Additionally, through this investigation, readers will gain a deeper understanding of how metrics can help to drive informed decision-making on delivering high-quality software and facilitate continuous improvement in testing practices.Keywords: software testing, software metrics, testing effectiveness, black box testing, random testing, adaptive random testing, combinatorial testing, fuzz testing, equivalence partition, boundary value analysis, white box testing
Procedia PDF Downloads 803601 Anomalous Behaviors of Visible Luminescence from Graphene Quantum Dots
Authors: Hyunho Shin, Jaekwang Jung, Jeongho Park, Sungwon Hwang
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For the application of graphene quantum dots (GQDs) to optoelectronic nanodevices, it is of critical importance to understand the mechanisms which result in novel phenomena of their light absorption/emission. The optical transitions are known to be available up to ~6 eV in GQDs, especially useful for ultraviolet (UV) photodetectors (PDs). Here, we present size-dependent shape/edge-state variations of GQDs and visible photoluminescence (PL) showing anomalous size dependencies. With varying the average size (da) of GQDs from 5 to 35 nm, the peak energy of the absorption spectra monotonically decreases, while that of the visible PL spectra unusually shows nonmonotonic behaviors having a minimum at diameter ∼17 nm. The PL behaviors can be attributed to the novel feature of GQDs, that is, the circular-to-polygonal-shape and corresponding edge-state variations of GQDs at diameter ∼17 nm as the GQD size increases, as demonstrated by high resolution transmission electron microscopy. We believe that such a comprehensive scheme in designing device architecture and the structural formulation of GQDs provides a device for practical realization of environmentally benign, high performance flexible devices in the future.Keywords: graphene, quantum dot, size, photoluminescence
Procedia PDF Downloads 2843600 Three Dimensional Simulation of the Transient Modeling and Simulation of Different Gas Flows Velocity and Flow Distribution in Catalytic Converter with Porous Media
Authors: Amir Reza Radmanesh, Sina Farajzadeh Khosroshahi, Hani Sadr
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The transient catalytic converter performance is governed by complex interactions between exhaust gas flow and the monolithic structure of the catalytic converter. Stringent emission regulations around the world necessitate the use of highly-efficient catalytic converters in vehicle exhaust systems. Computational fluid dynamics (CFD) is a powerful tool for calculating the flow field inside the catalytic converter. Radial velocity profiles, obtained by a commercial CFD code, present very good agreement with respective experimental results published in the literature. However the applicability of CFD for transient simulations is limited by the high CPU demands. In the present work, Geometric modeling ceramic monolith substrate is done with square shaped channel type of Catalytic converter and it is coated platinum and palladium. This example illustrates the effect of flow distribution on thermal response of a catalytic converter and different gas flow velocities, during the critical phase of catalytic converter warm up.Keywords: catalytic converter, computational fluid dynamic, porous media, velocity distribution
Procedia PDF Downloads 8503599 Study of the Effect of Rotation on the Deformation of a Flexible Blade Rotor
Authors: Aref Maalej, Marwa Fakhfakh, Wael Ben Amira
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We present in this work a numerical investigation of fluid-structure interaction to study the elastic behavior of flexible rotors. The principal aim is to provide the effect of the aero/hydrodynamic parameters on the bending deformation of flexible rotors. This study is accomplished using the strong two-way fluid-structure interaction (FSI) developed by the ANSYS Workbench software. This method is used for coupling the fluid solver to the transient structural solver to study the elastic behavior of flexible rotors in water. In this study, we use a moderately flexible rotor modeled by a single blade with simplified rectangular geometry. In this work, we focus on the effect of the rotational frequency on the flapwise bending deformation. It is demonstrated that the blade deforms in the downstream direction, and the amplitude of these deformations increases with the rotational frequencies. Also, from a critical frequency, the blade begins to deform in the upstream direction.Keywords: numerical simulation, flexible blade, fluid-structure interaction, ANSYS workbench, flapwise deformation
Procedia PDF Downloads 773598 Wind Velocity Mitigation for Conceptual Design: A Spatial Decision (Support Framework)
Authors: Mohamed Khallaf, Hossein M Rizeei
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Simulating wind pattern behavior over proposed urban features is critical in the early stage of the conceptual design of both architectural and urban disciplines. However, it is typically not possible for designers to explore the impact of wind flow profiles across new urban developments due to a lack of real data and inaccurate estimation of building parameters. Modeling the details of existing and proposed urban features and testing them against wind flows is the missing part of the conceptual design puzzle where architectural and urban discipline can focus. This research aims to develop a spatial decision-support design method utilizing LiDAR, GIS, and performance-based wind simulation technology to mitigate wind-related hazards on a design by simulating alternative design scenarios at the pedestrian level prior to its implementation in Sydney, Australia. The result of the experiment demonstrates the capability of the proposed framework to improve pedestrian comfort in relation to wind profile.Keywords: spatial decision-support design, performance-based wind simulation, LiDAR, GIS
Procedia PDF Downloads 1143597 Crystalline Silica Exposure in Tunnelling: Identifying Barriers to Safe Practices
Authors: Frederick Anlimah, Vinod Gopaldasani, Catherine MacPhail, Brian Davies
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The construction industry, particularly tunnel construction, exposes workers to respirable crystalline silica (RCS), which can cause incurable illnesses such as silicosis and lung cancer. Despite various control measures, exposures remain inadequately controlled. This research aimed to identify the barriers and challenges hindering the implementation of effective controls and the adoption of safe work practices to protect workers from RCS exposure in tunnelling. A mixed-method approach was employed for this research. Tunnel construction workers were observed, surveyed and interviewed to gauge their knowledge and attitudes and understand their challenges in reducing RCS exposure. The preliminary analysis of the data reveals a diverse array of sociotechnical factors interacting to influence RCS exposure. It is noteworthy that participants consistently emphasised the project as the most exemplary one they have been involved in, although there is room for improvement. While there is a commendable level of knowledge about RCS exposure and control in tunnelling, there is a striking lack of perceived satisfaction regarding dust control. Several factors were identified as interacting to prevent the effective management of dust. These include perceived time pressure, absence of on-tool dust controls, low risk perceptions among workers, and inadequate enforcement of controls. Moreover, participants highlighted communication and heat-related challenges as hindrances to the continuous wear of respirators. This research highlights the need for a paradigm shift in tunnel construction to address the barriers associated with RCS exposure reduction. It emphasises the importance of collaboration among various stakeholders, advocating for more effective controls and enforcement strategies and enhanced worker education through knowledge sharing.Keywords: respirable crystalline silica, dust control, worker practices, exposure prevention, silicosis
Procedia PDF Downloads 583596 Intelligent Irrigation Control System Using Wireless Sensors and Android Application
Authors: Rajeshwari Madli, Santhosh Hebbar, Vishwanath Heddoori, G. V. Prasad
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Agriculture is the major occupation in India and forms the backbone of Indian economy in which irrigation plays a crucial role for increasing the quality and quantity of crop yield. In spite of many revolutionary advancements in agriculture, there has not been a dramatic increase in agricultural performance. Lack of irrigation infrastructure and agricultural knowledge are the critical factors influencing agricultural performance. However, by using advanced agricultural equipment, the effect of these factors can be curtailed. The presented system aims at increasing the yield of crops by using an intelligent irrigation controller that makes use of wireless sensors. Sensors are used to monitor primary parameters such as soil moisture, soil pH, temperature and humidity. Irrigation decisions are taken based on the sensed data and the type of crop being grown. The system provides a mobile application in which farmers can remotely monitor and control the irrigation system. Also, the water pump is protected against damages due to voltage variations and dry running.Keywords: android application, Bluetooth, wireless sensors, irrigation, temperature, soil pH
Procedia PDF Downloads 3753595 Methodology of Construction Equipment Optimization for Earthwork
Authors: Jaehyun Choi, Hyunjung Kim, Namho Kim
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Earthwork is one of the critical civil construction operations that require large-quantities of resources due to its intensive dependency upon construction equipment. Therefore, efficient construction equipment management can highly contribute to productivity improvements and cost savings. Earthwork operation utilizes various combinations of construction equipment in order to meet project requirements such as time and cost. Identification of site condition and construction methods should be performed in advance in order to develop a proper execution plan. The factors to be considered include capacity of equipment assigned, the method of construction, the size of the site, and the surrounding condition. In addition, optimal combination of various construction equipment should be selected. However, in real world practice, equipment utilization plan is performed based on experience and intuition of management. The researchers evaluated the efficiency of various alternatives of construction equipment combinations by utilizing the process simulation model, validated the model from a case study project, and presented a methodology to find optimized plan among alternatives.Keywords: earthwork operation, construction equipment, process simulation, optimization
Procedia PDF Downloads 4193594 Feature-Based Summarizing and Ranking from Customer Reviews
Authors: Dim En Nyaung, Thin Lai Lai Thein
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Due to the rapid increase of Internet, web opinion sources dynamically emerge which is useful for both potential customers and product manufacturers for prediction and decision purposes. These are the user generated contents written in natural languages and are unstructured-free-texts scheme. Therefore, opinion mining techniques become popular to automatically process customer reviews for extracting product features and user opinions expressed over them. Since customer reviews may contain both opinionated and factual sentences, a supervised machine learning technique applies for subjectivity classification to improve the mining performance. In this paper, we dedicate our work is the task of opinion summarization. Therefore, product feature and opinion extraction is critical to opinion summarization, because its effectiveness significantly affects the identification of semantic relationships. The polarity and numeric score of all the features are determined by Senti-WordNet Lexicon. The problem of opinion summarization refers how to relate the opinion words with respect to a certain feature. Probabilistic based model of supervised learning will improve the result that is more flexible and effective.Keywords: opinion mining, opinion summarization, sentiment analysis, text mining
Procedia PDF Downloads 3233593 The Emotional Education in the Development of Intercultural Competences
Authors: Montserrrat Dopico Gonzalez, Ramon Lopez Facal
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The development of a critical, open and plural citizenship constitutes one of the main challenges of the school institution in the present multicultural societies. Didactics in Social Sciences has conducted important contributions to the development of active methodologies to promote the development of the intercultural competencies of the student body. Research in intercultural education has demonstrated the efficiency of the cooperative learning techniques to improve the intercultural relations in the classroom. Our study proposes to check the effect that, concerning the development of intercultural competencies of the student body, the emotional education can have in the context of the use of active methodologies such as the learning by projects and the cooperative learning. To that purpose, a programme of intervention based on activities focussed on controversial issues related to cultural diversity has been implemented in several secondary schools. Through a methodology which combines intercultural competence scales with interviews and also with the analysis of the school body’s productions, the persistence of stereotypes against immigration and the efficacy of the introduction of emotional education elements in the development of intercultural competencies have both been observed.Keywords: active methodologies, didactics in social sciences, intercultural competences, intercultural education
Procedia PDF Downloads 1503592 FWGE Production From Wheat Germ Using Co-culture of Saccharomyces cerevisiae and Lactobacillus plantarum
Authors: Valiollah Babaeipour, Mahdi Rahaie
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food supplements are rich in specific nutrients and bioactive compounds that eliminate free radicals and improve cellular metabolism. The major bioactive compounds are found in bran and cereal sprouts. Secondary metabolites of these microorganisms have antioxidant properties that can be used alone or in combination with chemotherapy and radiation therapy to treat cancer. Biologically active compounds such as benzoquinone derivatives extracted from fermented wheat germ extract (FWGE) have several positive effects on the overall state of human health and strengthen the immune system. The present work describes the discontinuous fermentation of raw wheat germ for FWGE production through the simultaneous culture process using the probiotic strains of Saccharomyces cerevisiae, Lactobacillus plantarum, and the possibility of using solid waste. To increase production efficiency, first to select important factors in the optimization of each fermentation process, using a factorial statistical scheme of stirring fraction (120 to 200 rpm), dilution of solids to solvent (1 to 8-12), fermentation time (16 to 24 hours) and strain to wheat germ ratio (20% to 50%) were studied and then simultaneous culture was performed to increase the yields of 2 and 6 dimethoxybenzoquinone (2,6-DMBQ). Since 2 and 6 dimethoxy benzoquinone were fermented as the main biologically active compound in wheat germ extract, UV-Vis analysis was performed to confirm the presence of 2 and 6 dimethoxy benzoquinone in the final product. In addition, 2,6-DMBQ of some products was isolated in a non-polar C-18 column and quantified using high performance liquid chromatography (HPLC). Based on our findings, it can be concluded that the increase of 2 and 6 dimethoxybenzoquinone in the simultaneous culture of Saccharomyces cerevisiae - Lactobacillus plantarum compared to pure culture of Saccharomyces cerevisiae (from 1.89 mg / g) to 28.9% (2.66 mg / g) Increased.Keywords: wheat germ, FWGE, saccharomyces cerevisiae, lactobacillus plantarum, co-culture, 2, 6-DMBQ
Procedia PDF Downloads 1223591 Free Energy Computation of A G-Quadruplex-Ligand Structure: A Classical Molecular Dynamics and Metadynamics Simulation Study
Authors: Juan Antonio Mondragon Sanchez, Ruben Santamaria
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The DNA G-quadruplex is a four-stranded DNA structure formed by stacked planes of four base paired guanines (G-quartet). Guanine rich DNA sequences appear in many sites of genomic DNA and can potential form G-quadruplexes, such as those occurring at 3'-terminus of the human telomeric DNA. The formation and stabilization of a G-quadruplex by small ligands at the telomeric region can inhibit the telomerase activity. In turn, the ligands can be used to down regulate oncogene expression making G-quadruplex an attractive target for anticancer therapy. Many G-quadruplex ligands have been proposed with a planar core to facilitate the pi–pi stacking and electrostatic interactions with the G-quartets. However, many drug candidates are impossibilitated to discriminate a G-quadruplex from a double helix DNA structure. In this context, it is important to investigate the site topology for the interaction of a G-quadruplex with a ligand. In this work, we determine the free energy surface of a G-quadruplex-ligand to study the binding modes of the G-quadruplex (TG4T) with the daunomycin (DM) drug. The complex TG4T-DM is studied using classical molecular dynamics in combination with metadynamics simulations. The metadynamics simulations permit an enhanced sampling of the conformational space with a modest computational cost and obtain free energy surfaces in terms of the collective variables (CV). The free energy surfaces of TG4T-DM exhibit other local minima, indicating the presence of additional binding modes of daunomycin that are not observed in short MD simulations without the metadynamics approach. The results are compared with similar calculations on a different structure (the mutated mu-G4T-DM where the 5' thymines on TG4T-DM have been deleted). The results should be of help to design new G-quadruplex drugs, and understand the differences in the recognition topology sites of the duplex and quadruplex DNA structures in their interaction with ligands.Keywords: g-quadruplex, cancer, molecular dynamics, metadynamics
Procedia PDF Downloads 4523590 Grid-Connected Photovoltaic System: System Overview and Sizing Principles
Authors: Najiya Omar, Hamed Aly, Timothy Little
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The optimal size of a photovoltaic (PV) array is considered a critical factor in designing an efficient PV system due to the dependence of the PV cell performance on temperature. A high temperature can lead to voltage losses of solar panels, whereas a low temperature can cause voltage overproduction. There are two possible scenarios of the inverter’s operation in which they are associated with the erroneous calculations of the number of PV panels: 1) If the number of the panels is scant and the temperature is high, the minimum voltage required to operate the inverter will not be reached. As a result, the inverter will shut down. 2) Comparably, if the number of panels is excessive and the temperature is low, the produced voltage will be more than the maximum limit of the inverter which can cause the inverter to get disconnected or even damaged. This article aims to assess theoretical and practical methodologies to calculate size and determine the topology of a PV array. The results are validated by applying an experimental evaluation for a 100 kW Grid-connected PV system for a location in Halifax, Nova Scotia and achieving a satisfactory system performance compared to the previous work done.Keywords: sizing PV panels, theoretical and practical methodologies, topology of PV array, grid-connected PV
Procedia PDF Downloads 352