Search results for: Luan Trong Nguyen
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 295

Search results for: Luan Trong Nguyen

175 A Study on the Readers' Motivation and Satisfaction on Sports Newspaper in Vietnam

Authors: Trang Huyen Nguyen, Thien Tri Huynh

Abstract:

The objectives of this paper were to determine demographics of readers at Hochiminh city (HCMC), study reading motivation which affected citizens to read sports newspapers and measure readers’ satisfaction on issues related sports newspapers. Subjects of this survey were HCMC’s citizens. After collecting data, there were 568 useful feedbacks (the rate of response was 94.7%). The data analysis in the study included descriptive statistics and inferred statistics by SPSS 16.0 program for the research questions. The majority of respondents were male, from 24 to 32 years old, got the first degree and earned monthly from $US 150 to 300. Moreover, they were government officials and read newspaper from 11 to 20 times per month, bought newspapers by themselves. Finding information to predict results of sports matches was the highest motive affected readers; and the diversity information was the most pleasure that readers felt about sports newspapers. According to research findings, the board of editors could use the worthy information to make a strategic plan for newspaper on contents as well as design to meet the increasing demands of readers.

Keywords: motivation, satisfaction, readers, sports newspapers

Procedia PDF Downloads 304
174 Hardware-in-the-Loop Test for Automatic Voltage Regulator of Synchronous Condenser

Authors: Ha Thi Nguyen, Guangya Yang, Arne Hejde Nielsen, Peter Højgaard Jensen

Abstract:

Automatic voltage regulator (AVR) plays an important role in volt/var control of synchronous condenser (SC) in power systems. Test AVR performance in steady-state and dynamic conditions in real grid is expensive, low efficiency, and hard to achieve. To address this issue, we implement hardware-in-the-loop (HiL) test for the AVR of SC to test the steady-state and dynamic performances of AVR in different operating conditions. Startup procedure of the system and voltage set point changes are studied to evaluate the AVR hardware response. Overexcitation, underexcitation, and AVR set point loss are tested to compare the performance of SC with the AVR hardware and that of simulation. The comparative results demonstrate how AVR will work in a real system. The results show HiL test is an effective approach for testing devices before deployment and is able to parameterize the controller with lower cost, higher efficiency, and more flexibility.

Keywords: automatic voltage regulator, hardware-in-the-loop, synchronous condenser, real time digital simulator

Procedia PDF Downloads 251
173 Effect of Scalping on the Mechanical Behavior of Coarse Soils

Authors: Nadine Ali Hassan, Ngoc Son Nguyen, Didier Marot, Fateh Bendahmane

Abstract:

This paper aims at presenting a study of the effect of scalping methods on the mechanical properties of coarse soils by resorting to numerical simulations based on the discrete element method (DEM) and experimental triaxial tests. Two reconstitution methods are used, designated as scalping method and substitution method. Triaxial compression tests are first simulated on a granular materials with a grap graded particle size distribution by using the DEM. We study the effect of these reconstitution methods on the stress-strain behavior of coarse soils with different fine contents and with different ways to control the densities of the scalped and substituted materials. Experimental triaxial tests are performed on original mixtures of sands and gravels with different fine contents and on their corresponding scalped and substituted samples. Numerical results are qualitatively compared to experimental ones. Agreements and discrepancies between these results are also discussed.

Keywords: coarse soils, mechanical behavior, scalping, replacement, triaxial devices

Procedia PDF Downloads 207
172 A Step-by-Step Analytical Protocol For Detecting and Identifying Minor Differences In Like Materials and Polymers Using Pyrolysis -Gas Chromatography/Mass Spectrometry Technique

Authors: Athena Nguyen, Rojin Belganeh

Abstract:

Detecting and identifying differences in like polymer materials are key factors in failure and deformulation analysis, and reverse engineering. Pyrolysis-GC/MS is an easy solid sample introduction technique which expands the application areas of gas chromatography and mass spectrometry. The Micro furnace pyrolyzer is directly interfaced with the GC injector preventing any potential of cold spot, carryover, and cross contamination. In this presentation, the analysis of the differences in three polystyrene samples is demonstrated. Although the three samples look very similar by Evolve gas analysis (EGA) and Flash pyrolysis, there are indications of small levels of other materials. By performing Thermal desorption-GC/MS, the additive compounds between samples show the differences. EGA, flash pyrolysis, and thermal desorption analysis are the different modes of operations of the micro-furnace pyrolyzer enabling users to perform multiple analytical techniques.

Keywords: Gas chromatography/Mass spectrometry, pyrolysis, pyrolyzer, thermal desorption-GC/MS

Procedia PDF Downloads 187
171 Speciation Analysis by Solid-Phase Microextraction and Application to Atrazine

Authors: K. Benhabib, X. Pierens, V-D Nguyen, G. Mimanne

Abstract:

The main hypothesis of the dynamics of solid phase microextraction (SPME) is that steady-state mass transfer is respected throughout the SPME extraction process. It considers steady-state diffusion is established in the two phases and fast exchange of the analyte at the solid phase film/water interface. An improved model is proposed in this paper to handle with the situation when the analyte (atrazine) is in contact with colloid suspensions (carboxylate latex in aqueous solution). A mathematical solution is obtained by substituting the diffusion coefficient by the mean of diffusion coefficient between analyte and carboxylate latex, and also thickness layer by the mean thickness in aqueous solution. This solution provides an equation relating the extracted amount of the analyte to the extraction a little more complicated than previous models. It also gives a better description of experimental observations. Moreover, the rate constant of analyte obtained is in satisfactory agreement with that obtained from the initial curve fitting.

Keywords: pesticide, solid-phase microextraction (SPME) methods, steady state, analytical model

Procedia PDF Downloads 488
170 Transforming Water-Energy-Gas Industry through Smart Metering and Blockchain Technology

Authors: Khoi A. Nguyen, Rodney A. Stewart, Hong Zhang

Abstract:

Advanced metering technologies coupled with informatics creates an opportunity to form digital multi-utility service providers. These providers will be able to concurrently collect a customers’ medium-high resolution water, electricity and gas demand data and provide user-friendly platforms to feed this information back to customers and supply/distribution utility organisations. With the emergence of blockchain technology, a new research area has been explored which helps bring this multi-utility service provider concept to a much higher level. This study aims at introducing a breakthrough system architecture where smart metering technology in water, energy, and gas (WEG) are combined with blockchain technology to provide customer a novel real-time consumption report and decentralized resource trading platform. A pilot study on 4 properties in Australia has been undertaken to demonstrate this system, where benefits for customers and utilities are undeniable.

Keywords: blockchain, digital multi-utility, end use, demand forecasting

Procedia PDF Downloads 171
169 Application of PSK Modulation in ADS-B 1090 Extended Squitter Authentication

Authors: A-Q. Nguyen. A. Amrhar, J. Zambrano, G. Brown, O.A. Yeste-Ojeda, R. Jr. Landry

Abstract:

Since the presence of Next Generation Air Transportation System (NextGen), Automatic Dependent Surveillance-Broadcast (ADS-B) has raised specific concerns related to the privacy and security, due to its vulnerable, low-level of security and limited payload. In this paper, the authors introduce and analyze the combination of Pulse Amplitude Modulation (PAM) and Phase Shift Keying (PSK) Modulation in conventional ADS-B, forming Secure ADS-B (SADS-B) avionics. In order to demonstrate the potential of this combination, Hardware-in-the-loop (HIL) simulation was used. The tests' results show that, on the one hand, SADS-B can offer five times the payload as its predecessor. This additional payload of SADS-B can be used in various applications, therefore enhancing the ability and efficiency of the current ADS-B. On the other hand, by using the extra phase modulated bits as a digital signature to authenticate ADS-B messages, SADS-B can increase the security of ADS-B, thus ensure a more secure aviation as well. More importantly, SADS-B is compatible with the current ADS-B In and Out. Hence, no significant modifications will be needed to implement this idea. As a result, SADS-B can be considered the most promising approach to enhance the capability and security of ADS-B.

Keywords: ADS-B authentication, ADS-B security, NextGen ADS-B, PSK signature, secure ADS-B

Procedia PDF Downloads 319
168 Separation of Chlorinated Plastics and Immobilization of Heavy Metals in Hazardous Automotive Shredder Residue

Authors: Srinivasa Reddy Mallampati, Chi-Hyeon Lee, Nguyen Thi Thanh Truc, Byeong-Kyu Lee

Abstract:

In the present study, feasibility of the selective surface hydrophilization of polyvinyl chloride (PVC) by microwave treatment was evaluated to facilitate the separation from automotive shredder residue (ASR), by the froth flotation. The combination of 60 sec microwave treatment with PAC, a sharp and significant decrease about 16.5° contact angle of PVC was observed in ASR plastic compared with other plastics. The microwave treatment with the addition of PAC resulted in a synergetic effect for the froth flotation, which may be a result of the 90% selective separation of PVC from ASR plastics, with 82% purity. While, simple mixing with a nanometallic Ca/CaO/PO4 dispersion mixture immobilized 95-100% of heavy metals in ASR soil/residues. The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO4 was lower than the Korean standard regulatory limit for hazardous waste landfills. Microwave treatment can be a simple and effective method for PVC separation from ASR plastics.

Keywords: automotive shredder residue, chlorinated plastics, hazardous waste, heavy metals, immobilization, separation

Procedia PDF Downloads 521
167 Tenofovir-Amino Acid Conjugates Act as Polymerase Substrates: Implications for Avoiding Cellular Phosphorylation in the Discovery of Nucleotide Analogs

Authors: Weijie Gu, Sergio Martinez, Hoai Nguyen, Hongtao Xu, Piet Herdewijn, Steven De Jonghe, Kalyan Das

Abstract:

Nucleotide analogs are used for treating viral infections such as HIV, hepatitis B, hepatitis C, influenza, and SARS-CoV-2. To become polymerase substrates, a nucleotide analog must be phosphorylated by cellular kinases, which are rate-limiting. The goal of this study is to develop dNTP/NTP analogs directly from nucleotides. Tenofovir (TFV) analogs were synthesized by conjugating with natural or unnatural amino acids. It demonstrates that some conjugates act as dNTP analogs, and HIV-1 reverse transcriptase (RT) catalytically incorporates the TFV part as the chain terminator. X-ray structures in complex with HIV-1 RT/dsDNA showed binding of the conjugates at the polymerase active site, however, in different modes in the presence of Mg²⁺ vs. Mn²⁺ ions. The adaptability of the compounds is seemingly essential for catalytic incorporation of TFV by RT. 4d with a carboxyl sidechain demonstrated the highest incorporation. 4e showed weak incorporation and rather behaved as a dNTP-competitive inhibitor. This result advocates the feasibility of designing NTP/dNTP analogs by chemical substitutions to nucleotide analogs.

Keywords: dNTP analogs, nucleotide analogs, polymerase, tenofovir, X-ray structure

Procedia PDF Downloads 153
166 High Electrochemical Performance of Electrode Material Based On Mesoporous RGO@(Co,Mn)3O4 Nanocomposites

Authors: Charmaine Lamiel, Van Hoa Nguyen, Deivasigamani Ranjith Kumar, Jae-Jin Shim

Abstract:

The quest for alternative sources of energy storage had led to the exploration on supercapacitors. Hybrid supercapacitors, a combination of carbon-based material and transition metals, had yielded long and improved cycle life as well as high energy and power densities. In this study, microwave irradiation was used for the facile and rapid synthesis of mesoporous RGO@(Co,Mn)3O4 nanosheets as an active electrode material. The advantages of this method include the non-use of reducing agents and acidic medium, and no further post-heat treatment. Additionally, it offers shorter reaction time at low temperature and low power requirement, which allows low fabrication and energy cost. The as-prepared electrode material demonstrated a high capacitance of 953 F•g−1 at 1 A•g−1 in a 6 M KOH electrolyte. Furthermore, the electrode exhibited a high energy density of 76.2 Wh•kg−1 (power density of 720 W•kg−1) and a high power density of 7200 W•kg−1 (energy density of 38 Wh•kg−1). The successful synthesis was considered to be efficient and cost-effective, with very promising electrochemical performance that can be used as an active material in supercapacitors.

Keywords: cobalt manganese oxide, electrochemical, graphene, microwave synthesis, supercapacitor

Procedia PDF Downloads 358
165 Prediction of California Bearing Ratio from Physical Properties of Fine-Grained Soils

Authors: Bao Thach Nguyen, Abbas Mohajerani

Abstract:

The California bearing ratio (CBR) has been acknowledged as an important parameter to characterize the bearing capacity of earth structures, such as earth dams, road embankments, airport runways, bridge abutments, and pavements. Technically, the CBR test can be carried out in the laboratory or in the field. The CBR test is time-consuming and is infrequently performed due to the equipment needed and the fact that the field moisture content keeps changing over time. Over the years, many correlations have been developed for the prediction of CBR by various researchers, including the dynamic cone penetrometer, undrained shear strength, and Clegg impact hammer. This paper reports and discusses some of the results from a study on the prediction of CBR. In the current study, the CBR test was performed in the laboratory on some fine-grained subgrade soils collected from various locations in Victoria. Based on the test results, a satisfactory empirical correlation was found between the CBR and the physical properties of the experimental soils.

Keywords: California bearing ratio, fine-grained soils, soil physical properties, pavement, soil test

Procedia PDF Downloads 509
164 Advanced Catechol-Modified Chitosan Hydrogels with the Inducement of Iron (III) Ion at Acidic Condition

Authors: Ngoc Quang Nguyen, Daewon Sohn

Abstract:

Chitosan (CS) is a natural polycationic polysaccharide and pH-sensitive polymer with incomplete deacetylation from claiming chitin. It is also a guaranteeing material in terms of pharmaceutical, chemical, and sustenance industry due to its exceptional structure (reactive –OH and –NH2 groups). In this study, a catechol-functionalized chitosan (CCS, for an eminent level for substitution) was synthesized and propelled by marine mussel cuticles in place on research those intricate connections between Fe³⁺ and catechol under acidic conditions. The ratios of catechol, chitosan and other reagents decide the structure of the hydrogel. The gel formation is then well-maintained by dual cross-linking through electrostatic interactions between Fe³⁺ and CCS and covalent catechol-coupling-based coordinate bonds. The hydrogels showed enhanced cohesiveness and shock-absorbing properties with increasing pH due to coordinate bonds inspired by mussel byssal threads. Thus, the gelation time, rheological properties, UV-vis and ¹H-Nuclear Magnetic Resonance spectroscopy, and the morphologic aspects were elucidated to describe those crosslinking components and the physical properties of the chitosan backbones and hydrogel frameworks.

Keywords: catechol, chitosan, iron ion, gelation, hydrogel

Procedia PDF Downloads 141
163 Practitioner System in Vocational Education: Perspectives of Academics and Industry Practitioners

Authors: Hsiao-Tseng Lin, Nguyen Ngoc Dat, Szu-Mei Hsiao, R. J. Hernández-Díaz

Abstract:

The practitioner system has become an important tool for universities working to shrink the gap between industry and vocational education. Beginning in 2015, Meiho University conducted a consecutive three-year program for teaching excellence, funded in part by Taiwan’s Ministry of Education, with a total project funding of over $2.5 million USD. One of the highlights of this program is the recruitment of 300 industry practitioners to participate in collaborative teaching, a dual-mentor system, and curriculum planning. More than 60% of the practitioners boast more than 10 years of practical industry experience, and 52% of them have earned master's degree or higher. Students rated their overall program satisfaction over 4.5(out of 5.0) on average. This study explores the perspectives of academics and industry practitioners using in-depth interviews and surveys, along with an examination of the challenges of the practitioner system. The paper enables the framing of practitioner system policies by vocational education institutions and industry to facilitate more effective and efficient transfer of knowledge between academics and practitioners, leading to enhanced university competitive advantage, which would ultimately benefit society.

Keywords: collaborative teaching, industry practitioners, practitioner system, vocational education

Procedia PDF Downloads 211
162 A Literature Review on Sexual Abuse Prevention for People with Intellectual Disability

Authors: Hanh Thi My Nguyen, Phuong Thu Dinh

Abstract:

People with intellectual disability are at high risk for sexual abuse. The reasons may originate from their communication skills deficits, lack of skills and knowledge to protect themselves from sexual abuse, or limited access to sexual abuse prevention programs. This article aims to present a systematic review about strategies for preventing sexual abuse for young people with intellectual disability. A range of articles in 10 years from 2009 to 2018 are searched by using online database. 5 papers are included for the final review. The results of this comprehensive literature review showed that there are two main strategies used: programs designed for people with intellectual, including evaluation on sex education programs; and sexual education program for parents of children with intellectual disability. However, none of the papers were conducted in low-and middle-income countries. Therefore, cautions should be taken when it comes to interpret these findings. The findings of studies showed that participants increased their awareness and skills for protecting themselves from sexual abuse after participating in the programs. It is also recommended that more effective evidence-based programs should be developed.

Keywords: intellectual disability, prevention, sexual abuse, sexual education program

Procedia PDF Downloads 209
161 Influence of Confined Acoustic Phonons on the Shubnikov – de Haas Magnetoresistance Oscillations in a Doped Semiconductor Superlattice

Authors: Pham Ngoc Thang, Le Thai Hung, Nguyen Quang Bau

Abstract:

The influence of confined acoustic phonons on the Shubnikov – de Haas magnetoresistance oscillations in a doped semiconductor superlattice (DSSL), subjected in a magnetic field, DC electric field, and a laser radiation, has been theoretically studied based on quantum kinetic equation method. The analytical expression for the magnetoresistance in a DSSL has been obtained as a function of external fields, DSSL parameters, and especially the quantum number m characterizing the effect of confined acoustic phonons. When m goes to zero, the results for bulk phonons in a DSSL could be achieved. Numerical calculations are also achieved for the GaAs:Si/GaAs:Be DSSL and compared with other studies. Results show that the Shubnikov – de Haas magnetoresistance oscillations amplitude decrease as the increasing of phonon confinement effect.

Keywords: Shubnikov–de Haas magnetoresistance oscillations, quantum kinetic equation, confined acoustic phonons, laser radiation, doped semiconductor superlattices

Procedia PDF Downloads 317
160 Comparison of Methods for Detecting and Quantifying Amplitude Modulation of Wind Farm Noise

Authors: Phuc D. Nguyen, Kristy L. Hansen, Branko Zajamsek

Abstract:

The existence of special characteristics of wind farm noise such as amplitude modulation (AM) contributes significantly to annoyance, which could ultimately result in sleep disturbance and other adverse health effects for residents living near wind farms. In order to detect and quantify this phenomenon, several methods have been developed which can be separated into three types: time-domain, frequency-domain and hybrid methods. However, due to a lack of systematic validation of these methods, it is still difficult to select the best method for identifying AM. Furthermore, previous comparisons between AM methods have been predominantly qualitative or based on synthesised signals, which are not representative of the actual noise. In this study, a comparison between methods for detecting and quantifying AM has been carried out. The results are based on analysis of real noise data which were measured at a wind farm in South Australia. In order to evaluate the performance of these methods in terms of detecting AM, an approach has been developed to select the most successful method of AM detection. This approach uses a receiver operating characteristic (ROC) curve which is based on detection of AM in audio files by experts.

Keywords: amplitude modulation, wind farm noise, ROC curve

Procedia PDF Downloads 145
159 Cascaded Multi-Level Single-Phase Switched Boost Inverter

Authors: Van-Thuan Tran, Minh-Khai Nguyen, Geum-Bae Cho

Abstract:

Recently, multilevel inverters have become more attractive for researchers due to low total harmonic distortion (THD) in the output voltage and low electromagnetic interference (EMI). This paper proposes a single-phase cascaded H-bridge quasi switched boost inverter (CHB-qSBI) for renewable energy sources applications. The proposed inverter has the advantage over the cascaded H-bridge quasi-Z-source inverter (CHB-qZSI) in reducing two capacitors and two inductors. As a result, cost, weight, and size are reduced. Furthermore, the dc-link voltage of each module is controlled by individual shoot-through duty cycle to get the same values. Therefore, the proposed inverter solves the imbalance problem of dc-link voltage in traditional CHB inverter. This paper shows the operating principles and analysis of the single-phase cascaded H-bridge quasi switched boost inverter. Also, a control strategy for the proposed inverter is shown. Experimental and simulation results are shown to verify the operating principle of the proposed inverter.

Keywords: renewable energy sources, cascaded h-bridge inverter, quasi switched boost inverter, quasi z-source inverter, multilevel inverter

Procedia PDF Downloads 334
158 Assembly Training: An Augmented Reality Approach Using Design Science Research

Authors: Stefan Werrlich, Phuc-Anh Nguyen, Kai Nitsche, Gunther Notni

Abstract:

Augmented Reality (AR) is a strong growing research topic. This innovative technology is interesting for several training domains like education, medicine, military, sports and industrial use cases like assembly and maintenance tasks. AR can help to improve the efficiency, quality and transfer of training tasks. Due to these reasons, AR becomes more interesting for big companies and researchers because the industrial domain is still an unexplored field. This paper presents the research proposal of a PhD thesis which is done in cooperation with the BMW Group, aiming to explore head-mounted display (HMD) based training in industrial environments. We give a short introduction, describing the motivation, the underlying problems as well as the five formulated research questions we want to clarify along this thesis. We give a brief overview of the current assembly training in industrial environments and present some AR-based training approaches, including their research deficits. We use the Design Science Research (DSR) framework for this thesis and describe how we want to realize the seven guidelines, mandatory from the DSR. Furthermore, we describe each methodology which we use within that framework and present our approach in a comprehensive figure, representing the entire thesis.

Keywords: assembly, augmented reality, research proposal, training

Procedia PDF Downloads 246
157 Motor Controller Implementation Using Model Based Design

Authors: Cau Tran, Tu Nguyen, Tien Pham

Abstract:

Model-based design (MBD) is a mathematical and visual technique for addressing design issues in the fields of communications, signal processing, and complicated control systems. It is utilized in several automotive, aerospace, industrial, and motion control applications. Virtual models are at the center of the software development process with model based design. A method used in the creation of embedded software is model-based design. In this study, the LAT motor is modeled in a simulation environment, and the LAT motor control is designed with a cascade structure, a speed and current control loop, and a controller that is used in the next part. A PID structure serves as this controller. Based on techniques and motor parameters that match the design goals, the PID controller is created for the model using traditional design principles. The MBD approach will be used to build embedded software for motor control. The paper will be divided into three distinct sections. The first section will introduce the design process and the benefits and drawbacks of the MBD technique. The design of control software for LAT motors will be the main topic of the next section. The experiment's results are the subject of the last section.

Keywords: model based design, limited angle torque, intellectual property core, hardware description language, controller area network, user datagram protocol

Procedia PDF Downloads 94
156 An Assessment of the Effects of Microbial Products on the Specific Oxygen Uptake in Submerged Membrane Bioreactor

Authors: M. F. R. Zuthi, H. H. Ngo, W. S. Guo, S. S. Chen, N. C. Nguyen, L. J. Deng, T. D. C Tran

Abstract:

Sustaining a desired rate of oxygen transfer for microbial activity is a matter of major concern for Biological Wastewater Treatment (MBR). The study reported in the paper was aimed at assessing the effects of microbial products on the Specific Oxygen Uptake Rate (SOUR) in a Conventional Membrane Bioreactor (CMBR) and that in a Sponge Submerged MBR (SSMBR). The production and progressive accumulation of Soluble Microbial Products (SMP) and Bound-Extracellular Polymeric Substances (BEPS) were found affecting the SOUR of the microorganisms which varied at different stages of operation of the MBR systems depending on the variable concentrations of the SMP/bEPS. The effect of bEPS on the SOUR was stronger in the SSMBR compared to that of the SMP, while relative high concentrations of SMP had adverse effects on the SOUR of the CMBR system. Of the different mathematical correlations analyzed in the study, logarithmic mathematical correlations could be established between SOUR and bEPS in SSMBR, and similar correlations could also be found between SOUR and SMP concentrations in the CMBR.

Keywords: microbial products, microbial activity, specific oxygen uptake rate, membrane bioreactor

Procedia PDF Downloads 308
155 Mentees’ Agency in Practicum: A Qualitative Study of Two Teacher Education Programs in Vietnam

Authors: Tien Nguyen

Abstract:

The relationship between mentors and mentees in teaching practicum has received the attention of researchers and been widely investigated. Mentors’ authority and power have captured a large and growing body of the literature in the field of teaching practicum. This article revisits mentor-mentee relationship and shifts the focus to mentees’ agency in planning and delivering lessons, an area which has been under-researched. Drawing on Vygotsky’s Zone of Proximal Development and Harré’s Positioning Theory, this qualitative study examines how mentees responded to mentors’ instructions in practicum. Interviews and classroom observations were conducted with 20 participants including both mentors and mentees across two English language teacher education programs in two different geographical locations in Vietnam. The result indicates that regardless of the similarities and/or differences of the programs, mentees’ agency varied in accordance with their identities in specific contexts. Specifically, mentees follow or resist to mentors’ feedback and instruction in revising their lesson plans and delivery these lessons, depending on their professional identities and institutional conditions. This study contributes to the importance of supporting the agency of mentees in teacher education.

Keywords: mentors, mentees, relationship, agency, professional identity, teacher education

Procedia PDF Downloads 141
154 Structural and Phase Transformations of Pure and Silica Treated Nanofibrous Al₂O₃

Authors: T. H. N. Nguyen, A. Khodan, M. Amamra, J-V. Vignes, A. Kanaev

Abstract:

The ultraporous nanofibrous alumina (NOA, Al2O3·nH2O) was synthesized by oxidation of laminated aluminium plates through a liquid mercury-silver layer in a humid atmosphere ~80% at 25°C. The material has an extremely high purity (99%), porosity (90%) and specific area (300 m2/g). The subsequent annealing of raw NOA permits obtaining pure transition phase (γ and θ) nanostructured materials. In this combination, we report on chemical, structural and phase transformations of pure and modified NOA by an impregnation of trimethylethoxysilane (TMES) and tetraethoxysilane (TEOS) during thermal annealing in the temperature range between 20 and 1650°C. The mass density, specific area, average diameter and specific area are analysed. The 3D model of pure NOA monoliths and silica modified NOA is proposed, which successfully describes the evolution of specific area, mass density and phase transformations. Activation energies of the mass transport in two regimes of surface diffusion and bulk sintering were obtained based on this model. We conclude about a common origin of modifications of the NOA morphology, chemical composition and phase transition.

Keywords: nanostructured materials, alumina (Al₂O₃), morphology, phase transitions

Procedia PDF Downloads 377
153 Unleashing the Potential of Green Finance in Architecture: A Promising Path for Balkan Countries

Authors: Luan Vardari, Dena Arapi Vardari

Abstract:

The Balkan countries, known for their diverse landscapes and cultural heritage, face the dual challenge of promoting economic growth while addressing pressing environmental concerns. In recent years, the concept of green finance has emerged as a powerful tool to achieve sustainable development and mitigate the environmental impact of various sectors, including architecture. This extended abstract explores the untapped potential of green finance in architecture within the Balkan region and highlights its role in driving sustainable construction practices and fostering a greener future. The abstract begins by defining green finance and emphasizing its relevance in the context of the architectural sector in Balkan countries. It underlines the benefits of green finance, such as economic growth, environmental conservation, and social well-being. Integrating green finance into architectural projects is important as a means to achieve sustainable development goals while promoting financial viability. Also, delves into the current state of green building practices in the Balkan countries and identifies the need for financial support to further drive adoption. It explores the existing regulatory frameworks and policies that promote sustainable architecture and discusses how green finance can complement these initiatives. Unique challenges faced by Balkan countries are highlighted, along with the potential opportunities that green finance presents in overcoming these challenges. We highlight successful sustainable architectural projects in the region to showcase the practical application of green finance in the Balkans. These projects exemplify the effective utilization of green finance mechanisms, resulting in tangible economic and environmental impacts, including job creation, energy efficiency, and reduced carbon emissions. The abstract concludes by identifying replicable models and lessons learned from these projects that can serve as a blueprint for future sustainable architecture initiatives in the Balkans. The importance of collaboration and knowledge sharing among stakeholders is emphasized. Engaging architects, financial institutions, governments, and local communities is crucial to promoting green finance in architecture. The abstract suggests the establishment of knowledge exchange platforms and regional/international networks to foster collaboration and facilitate the sharing of expertise among Balkan countries.

Keywords: sustainable finance, renewable energy, Balkan region, investment opportunities, green infrastructure, ESG criteria, architecture

Procedia PDF Downloads 68
152 Beijerinckia indica Extracellular Extract Mediated Green Synthesis of Silver Nanoparticles with Antioxidant and Antibacterial Activities against Clinical Pathogens

Authors: Gopalu Karunakaran, Matheswaran Jagathambal, Nguyen Van Minh, Evgeny Kolesnikov, Denis Kuznetsov

Abstract:

This work investigated the use of Beijerinckia indica extracellular extract for the synthesis of silver nanoparticles using AgNO3. The formation of nanoparticles was confirmed by different methods, such as UV-Vis absorption spectroscopy, XRD, FTIR, EDX, and TEM analysis. The formation of silver nanoparticles (AgNPs) was confirmed by the change in color from light yellow to dark brown. The absorbance peak obtained at 430 nm confirmed the presence of silver nanoparticles. The XRD analysis showed the cubic crystalline phase of the synthesized nanoparticles. FTIR revealed the presence of groups that acts as stabilizing and reducing agents for silver nanoparticles formation. The synthesized silver nanoparticles were generally found to be spherical in shape with size ranging from 5 to 20 nm, as evident by TEM analysis. These nanoparticles were found to inhibit pathogenic bacterial strains. This work proved that the bacterial extract is a potential eco-friendly candidate for the synthesis of silver nanoparticles with promising antibacterial and antioxidant properties. 

Keywords: antioxidant activity, antimicrobial activity, Beijerinckia indica, characterisation, extracellular extracts, silver nanoparticles

Procedia PDF Downloads 340
151 Reinforced Concrete Box Girder Bridge Hinge Replacement and Horizontal and Vertical Earthquake Restrainers

Authors: Kumars ZandParsa, Quynh Nguyen, Hadi Moradi

Abstract:

There are old cast-in-place concrete box girder bridges in California with inter-span hinges that are designed based on old earthquake codes. Hinge removal is part of the bridges’ earthquake retrofitting project, and hinges were removed and replaced with modified hinges per new earthquake codes. The span that has a hinge is divided into short and long cantilevers in which the short cantilever supports the long cantilever. In the recent bridge hinge replacement, the length of the short and long cantilevers were 20ft and 80ft, respectively. The seat in the new design is wider than the old design, and the horizontal and vertical movements of the deck at the hinge location must be computed to check if restraints are needed. In this paper, besides considering the conventional reinforced concrete box girder bridges, the hinge removal operations, along with the response spectrum analysis based on the El Centro 1940 earthquake, will be presented to verify if vertical and horizontal restrainers are needed.

Keywords: hinge replacement, restrainers, vertical earthquake, response spectrum analysis

Procedia PDF Downloads 581
150 Effect of Initial pH and Fermentation Duration on Total Phenolic Content and Antioxidant Activity of Carob Kibble Fermented with Saccharomyces cerevisiae

Authors: Thi Huong Vu, Haelee Fenton, Thi Huong Tra Nguyen, Gary Dykes

Abstract:

In the present study, a submerged fermentation of carob kibble with Saccharomyces cerevisiae (S. cerevisiae) was performed. The total phenolic content and antioxidant activity in fermented carob kibble were determined by Folin–Ciocalteu method and scavenging capacity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The study showed that S. cerevisiae improved total phenolic content by 45 % and 50 % in acetone and water extracts respectively. Similarly, the antioxidant capacity of water extracts increased by 25 % and 41%, while acetone extracts indicated by 70% and 80% in DPPH and ABTS respectively. It is also found that initial pH 7.0 was more effective in improvement of total phenolic content and antioxidant activity. The efficiency of treatment was recorded at 15 h. This report suggested that submerged fermentation with S. cerevisiae is a potential and cost effective manner to further increase bioactive compounds in carob kibble, which are in use for food, cosmetic and pharmaceutical industries.

Keywords: antioxidant activity, carob kibble, saccharomyces cerevisiae, submerged fermentation, total phenolics

Procedia PDF Downloads 306
149 Deepnic, A Method to Transform Each Variable into Image for Deep Learning

Authors: Nguyen J. M., Lucas G., Brunner M., Ruan S., Antonioli D.

Abstract:

Deep learning based on convolutional neural networks (CNN) is a very powerful technique for classifying information from an image. We propose a new method, DeepNic, to transform each variable of a tabular dataset into an image where each pixel represents a set of conditions that allow the variable to make an error-free prediction. The contrast of each pixel is proportional to its prediction performance and the color of each pixel corresponds to a sub-family of NICs. NICs are probabilities that depend on the number of inputs to each neuron and the range of coefficients of the inputs. Each variable can therefore be expressed as a function of a matrix of 2 vectors corresponding to an image whose pixels express predictive capabilities. Our objective is to transform each variable of tabular data into images into an image that can be analysed by CNNs, unlike other methods which use all the variables to construct an image. We analyse the NIC information of each variable and express it as a function of the number of neurons and the range of coefficients used. The predictive value and the category of the NIC are expressed by the contrast and the color of the pixel. We have developed a pipeline to implement this technology and have successfully applied it to genomic expressions on an Affymetrix chip.

Keywords: tabular data, deep learning, perfect trees, NICS

Procedia PDF Downloads 90
148 The Use of Seashell by-Products in Pervious Concrete Pavers

Authors: Dang Hanh Nguyen, Nassim Sebaibi, Mohamed Boutouil, Lydia Leleyter, Fabienne Baraud

Abstract:

Pervious concrete is a green alternative to conventional pavements with minimal fine aggregate and a high void content. Pervious concrete allows water to infiltrate through the pavement, thereby reducing the runoff and the requirement for stormwater management systems. Seashell By-Products (SBP) are produced in an important quantity in France and are considered as waste. This work investigated to use SBP in pervious concrete and produce an even more environmentally friendly product, Pervious Concrete Pavers. The research methodology involved substituting the coarse aggregate in the previous concrete mix design with 20%, 40% and 60% SBP. The testing showed that pervious concrete containing less than 40% SBP had strengths, permeability and void content which are comparable to the pervious concrete containing with only natural aggregate. The samples that contained 40% SBP or higher had a significant loss in strength and an increase in permeability and a void content from the control mix pervious concrete. On the basis of the results in this research, it was found that the natural aggregate can be substituted by SBP without affecting the delicate balance of a pervious concrete mix. Additional, it is recommended that the optimum replacement percentage for SBP in pervious concrete is 40 % direct replacement of natural coarse aggregate while maintaining the structural performance and drainage capabilities of the pervious concrete.

Keywords: seashell by-products, pervious concrete pavers, permeability, mechanical strength

Procedia PDF Downloads 483
147 A Corpus-Assisted Discourse Analysis of Adjectival Collocation of the Word 'Education' in the American Context

Authors: Ngan Nguyen

Abstract:

The study analyses adjectives collocating with the word ‘education’ in the American language of the Corpus of Global Web-based English using a combination of corpus linguistic and discourse analytical methods to examine not only language patterns but also social political ideologies around the topic. Significant conclusions are deduced: (1) there are a large number of adjectival collocates of the word education which have been identified and classified into four categories representing four different aspects of education: level, quality, forms and types of education; (2) education, as in combination with three first categories, carries the meaning as the act and process of teaching and learning while with the last category having the meaning of a particular kind of teaching or training; (3) higher education is the topic that gains most concerns from the American public; (4) five most significant ideologies are discovered from the corpus: higher education associates with financial affairs, higher education is an industry, monetary policy of the government on higher education, people require greater accessibility to higher education and people value higher education. The study contributes to the field of developing meanings of words through corpus analysis and the field of discourse analysis.

Keywords: adjectival collocation, American context, corpus linguistics, discourse analysis, education

Procedia PDF Downloads 346
146 Effects of Initial State on Opinion Formation in Complex Social Networks with Noises

Authors: Yi Yu, Vu Xuan Nguyen, Gaoxi Xiao

Abstract:

Opinion formation in complex social networks may exhibit complex system dynamics even when based on some simplest system evolution models. An interesting and important issue is the effects of the initial state on the final steady-state opinion distribution. By carrying out extensive simulations and providing necessary discussions, we show that, while different initial opinion distributions certainly make differences to opinion evolution in social systems without noises, in systems with noises, given enough time, different initial states basically do not contribute to making any significant differences in the final steady state. Instead, it is the basal distribution of the preferred opinions that contributes to deciding the final state of the systems. We briefly explain the reasons leading to the observed conclusions. Such an observation contradicts with a long-term belief on the roles of system initial state in opinion formation, demonstrating the dominating role that opinion mutation can play in opinion formation given enough time. The observation may help to better understand certain observations of opinion evolution dynamics in real-life social networks.

Keywords: opinion formation, Deffuant model, opinion mutation, consensus making

Procedia PDF Downloads 177