Search results for: tutorial instructional mode
906 Decode and Forward Cooperative Protocol Enhancement Using Interference Cancellation
Authors: Siddeeq Y. Ameen, Mohammed K. Yousif
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Cooperative communication systems are considered to be a promising technology to improve the system capacity, reliability and performances over fading wireless channels. Cooperative relaying system with a single antenna will be able to reach the advantages of multiple antenna communication systems. It is ideally suitable for the distributed communication systems; the relays can cooperate and form virtual MIMO systems. Thus the paper will aim to investigate the possible enhancement of cooperated system using decode and forward protocol. On decode and forward an attempt to cancel or at least reduce the interference instead of increasing the SNR values is achieved. The latter can be achieved via the use group of relays depending on the channel status from source to relay and relay to destination respectively. In the proposed system, the transmission time has been divided into two phases to be used by decode and forward protocol. The first phase has been allocated for the source to transmit its data whereas the relays and destination nodes are in receiving mode. On the other hand, the second phase is allocated for the first and second groups of relay nodes to relay the data to the destination node. Simulations results have shown an improvement in performance is achieved compared to the conventional decode and forward in terms of BER and transmission rate.Keywords: cooperative systems, decode and forward, interference cancellation, virtual MIMO
Procedia PDF Downloads 321905 A Simple Method for Evaluation of Uniformity for Gafchromic Sheets for Film Dosimetry
Authors: Fayzan Ahmed, Saad Bin Saeed, Abdul Qadir Jangda
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Gafchromic™ sheet are extensively used for the QA of intensity modulated radiation therapy and other in-vivo dosimetry. Intra-sheet Non-uniformity of scanner as well as film causes undesirable fluctuations which are reflected in dosimetry The aim of this study is to define a systematic and robust method to investigate the intra-sheet uniformity of the unexposed Gafchromic Sheets and the region of interest (ROI) of the scanner. Sheets of lot No#: A05151201 were scanned before and after the expiry period with the EPSON™ XL10000 scanner in the transmission mode, landscape orientation, and 72 dpi resolution. ROI of (8’x 10’ inches) equal to the sheet dimension in the center of the scanner is used to acquire images with full transmission, block transmission and with sheets in place. 500 virtual grids, created in MATALB® are imported as a macros in ImageJ (1.49m Wayne Rasband) to analyze the images. In order to remove the edge effects, the outer 86 grids are excluded from the analysis. The standard deviation of the block transmission and full transmission are 0.38% and 0.66% confirming a higher uniformity of the scanner. Expired and non-expired sheets have standard deviations of 2.18% and 1.29%, show that uniformity decreases after expiry. The results are promising and indicate a good potential of this method to be used as a uniformity check for scanner and unexposed Gafchromic sheets.Keywords: IMRT, film dosimetry, virtual grids, uniformity
Procedia PDF Downloads 424904 Correlation Analysis to Quantify Learning Outcomes for Different Teaching Pedagogies
Authors: Kanika Sood, Sijie Shang
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A fundamental goal of education includes preparing students to become a part of the global workforce by making beneficial contributions to society. In this paper, we analyze student performance for multiple courses that involve different teaching pedagogies: a cooperative learning technique and an inquiry-based learning strategy. Student performance includes student engagement, grades, and attendance records. We perform this study in the Computer Science department for online and in-person courses for 450 students. We will perform correlation analysis to study the relationship between student scores and other parameters such as gender, mode of learning. We use natural language processing and machine learning to analyze student feedback data and performance data. We assess the learning outcomes of two teaching pedagogies for undergraduate and graduate courses to showcase the impact of pedagogical adoption and learning outcome as determinants of academic achievement. Early findings suggest that when using the specified pedagogies, students become experts on their topics and illustrate enhanced engagement with peers.Keywords: bag-of-words, cooperative learning, education, inquiry-based learning, in-person learning, natural language processing, online learning, sentiment analysis, teaching pedagogy
Procedia PDF Downloads 75903 Modeling of Micro-Grid System Components Using MATLAB/Simulink
Authors: Mahmoud Fouad, Mervat Badr, Marwa Ibrahim
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Micro-grid system is presently considered a reliable solution for the expected deficiency in the power required from future power systems. Renewable power sources such as wind, solar and hydro offer high potential of benign power for future micro-grid systems. Micro-Grid (MG) is basically a low voltage (LV) or medium voltage (MV) distribution network which consists of a number of called distributed generators (DG’s); micro-sources such as photovoltaic array, fuel cell, wind turbine etc. energy storage systems and loads; operating as a single controllable system, that could be operated in both grid-connected and islanded mode. The capacity of the DG’s is sufficient to support all; or most, of the load connected to the micro-grid. This paper presents a micro-grid system based on wind and solar power sources and addresses issues related to operation, control, and stability of the system. Using Matlab/Simulink, the system is modeled and simulated to identify the relevant technical issues involved in the operation of a micro-grid system based on renewable power generation units.Keywords: micro-grid system, photovoltaic, wind turbine, energy storage, distributed generation, modeling
Procedia PDF Downloads 432902 Perceptions of College Students on Whether an Intelligent Tutoring System Is a Tutor
Authors: Michael Smalenberger
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Intelligent tutoring systems (ITS) are computer-based platforms which can incorporate artificial intelligence to provide step-by-step guidance as students practice problem-solving skills. ITS can replicate the benefits of one-on-one tutoring, foster transactivity in collaborative environments, and lead to substantial learning gains when used to supplement the instruction of a teacher or when used as the sole method of instruction. Developments improving the ease of ITS creation have recently increased their proliferation, leading many K-12 schools and institutions of higher education in the United States to regularly use ITS within classrooms. We investigated how students perceive their experience using an ITS. In this study, 111 undergraduate students used an ITS in a college-level introductory statistics course and were subsequently asked for feedback on their experience. Results show that their perceptions were generally favorable of the ITS, and most would seek to use an ITS both for STEM and non-STEM courses in the future. Along with detailed transaction-level data, this feedback also provides insights on the design of user-friendly interfaces, guidance on accessibility for students with impairments, the sequencing of exercises, students’ expectation of achievement, and comparisons to other tutoring experiences. We discuss how these findings are important for the creation, implementation, and evaluation of ITS as a mode and method of teaching and learning.Keywords: college statistics course, intelligent tutoring systems, in vivo study, student perceptions of tutoring
Procedia PDF Downloads 100901 A Process FMEA in Aero Fuel Pump Manufacturing and Conduct the Corrective Actions
Authors: Zohre Soleymani, Meisam Amirzadeh
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Many products are safety critical, so proactive analysis techniques are vital for them because these techniques try to identify potential failures before the products are produced. Failure Mode and Effective Analysis (FMEA) is an effective tool in identifying probable problems of product or process and prioritizing them and planning for its elimination. The paper shows the implementation of FMEA process to identify and remove potential troubles of aero fuel pumps manufacturing process and improve the reliability of subsystems. So the different possible causes of failure and its effects along with the recommended actions are discussed. FMEA uses Risk Priority Number (RPN) to determine the risk level. RPN value is depending on Severity(S), Occurrence (O) and Detection (D) parameters, so these parameters need to be determined. After calculating the RPN for identified potential failure modes, the corrective actions are defined to reduce risk level according to assessment strategy and determined acceptable risk level. Then FMEA process is performed again and RPN revised is calculated. The represented results are applied in the format of a case study. These results show the improvement in manufacturing process and considerable reduction in aero fuel pump production risk level.Keywords: FMEA, risk priority number, aero pump, corrective action
Procedia PDF Downloads 281900 Challenges of School Leadership
Authors: Stefan Ninković
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The main purpose of this paper is to examine the different theoretical approaches and relevant empirical evidence and thus, recognize some of the most pressing challenges faced by school leaders. This paper starts from the fact that the new mission of the school is characterized by the need for stronger coordination among students' academic, social and emotional learning. In this sense, school leaders need to focus their commitment, vision and leadership on the issues of students' attitudes, language, cultural and social background, and sexual orientation. More specifically, they should know what a good teaching is for student’s at-risk, students whose first language is not dominant in school, those who’s learning styles are not in accordance with usual teaching styles, or who are stigmatized. There is a rather wide consensus around the fact that the traditionally popular concept of instructional leadership of the school principal is no longer sufficient. However, in a number of "pro-leadership" circles, including certain groups of academic researchers, consultants and practitioners, there is an established tendency of attributing school principal an extraordinary influence towards school achievements. On the other hand, the situation in which all employees in the school are leaders is a utopia par excellence. Although leadership obviously can be efficiently distributed across the school, there are few findings that speak about sources of this distribution and factors making it sustainable. Another idea that is not particularly new, but has only recently gained in importance is related to the fact that the collective capacity of the school is an important resource that often remains under-cultivated. To understand the nature and power of collaborative school cultures, it is necessary to know that these operate in a way that they make their all collective members' tacit knowledge explicit. In this sense, the question is how leaders in schools can shape collaborative culture and create social capital in the school. Pressure exerted on schools to systematically collect and use the data has been accompanied by the need for school leaders to develop new competencies. The role of school leaders is critical in the process of assessing what data are needed and for what purpose. Different types of data are important: test results, data on student’s absenteeism, satisfaction with school, teacher motivation, etc. One of the most important tasks of school leaders are data-driven decision making as well as ensuring transparency of the decision-making process. Finally, the question arises whether the existing models of school leadership are compatible with the current social and economic trends. It is necessary to examine whether and under what conditions schools are in need for forms of leadership that are different from those that currently prevail. Closely related to this issue is also to analyze the adequacy of different approaches to leadership development in the school.Keywords: educational changes, leaders, leadership, school
Procedia PDF Downloads 335899 Reformulation of Theory of Critical Distances to Predict the Strength of Notched Plain Concrete Beams under Quasi Static Loading
Authors: Radhika V., J. M. Chandra Kishen
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The theory of critical distances (TCD), due to its appealing characteristics, has been successfully used in the past to predict the strength of brittle as well as ductile materials, weakened by the presence of stress risers under both static and fatigue loading. By utilising most of the TCD's unique features, this paper summarises an attempt for a reformulation of the point method of the TCD to predict the strength of notched plain concrete beams under mode I quasi-static loading. A zone of micro cracks, which is responsible for the non-linearity of concrete, is taken into account considering the concept of an effective elastic crack. An attempt is also made to correlate the value of the material characteristic length required for the application of TCD with the maximum aggregate size in the concrete mix, eliminating the need for any extensive experimentation prior to the application of TCD. The devised reformulation and the proposed power law based relationship is found to yield satisfactory predictions for static strength of notched plain concrete beams, with geometric dimensions of the beam, tensile strength, and maximum aggregate size of the concrete mix being the only needed input parameters.Keywords: characteristic length, effective elastic crack, inherent material strength, modeI loading, theory of critical distances
Procedia PDF Downloads 96898 Cost Analysis of Optimized Fast Network Mobility in IEEE 802.16e Networks
Authors: Seyyed Masoud Seyyedoshohadaei, Borhanuddin Mohd Ali
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To support group mobility, the NEMO Basic Support Protocol has been standardized as an extension of Mobile IP that enables an entire network to change its point of attachment to the Internet. Using NEMO in IEEE 802.16e (WiMax) networks causes latency in handover procedure and affects seamless communication of real-time applications. To decrease handover latency and service disruption time, an integrated scheme named Optimized Fast NEMO (OFNEMO) was introduced by authors of this paper. In OFNEMO a pre-establish multi tunnels concept, cross function optimization and cross layer design are used. In this paper, an analytical model is developed to evaluate total cost consisting of signaling and packet delivery costs of the OFNEMO compared with RFC3963. Results show that OFNEMO increases probability of predictive mode compared with RFC3963 due to smaller handover latency. Even though OFNEMO needs extra signalling to pre-establish multi tunnel, it has less total cost thanks to its optimized algorithm. OFNEMO can minimize handover latency for supporting real time application in moving networks.Keywords: fast mobile IPv6, handover latency, IEEE802.16e, network mobility
Procedia PDF Downloads 195897 Comparison of Interactive Performance of Clicking Tasks Using Cursor Control Devices under Different Feedback Modes
Authors: Jinshou Shi, Xiaozhou Zhou, Yingwei Zhou, Tuoyang Zhou, Ning Li, Chi Zhang, Zhanshuo Zhang, Ziang Chen
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In order to select the optimal interaction method for common computer click tasks, the click experiment test adopts the ISO 9241-9 task paradigm, using four common operations: mouse, trackball, touch, and eye control under visual feedback, auditory feedback, and no feedback. Through data analysis of various parameters of movement time, throughput, and accuracy, it is found that the movement time of touch-control is the shortest, the operation accuracy and throughput are higher than others, and the overall operation performance is the best. In addition, the motion time of the click operation with auditory feedback is significantly lower than the other two feedback methods in each operation mode experiment. In terms of the size of the click target, it is found that when the target is too small (less than 14px), the click performance of all aspects is reduced, so it is proposed that the design of the interface button should not be less than 28px. In this article, we discussed in detail the advantages and disadvantages of the operation and feedback methods, and the results of the discussion of the click operation can be applied to the design of the buttons in the interactive interface.Keywords: cursor control performance, feedback, human computer interaction, throughput
Procedia PDF Downloads 194896 Free Radical Dosimetry for Ultrasound in Terephthalic Acid Solutions Containing Gold Nanoparticles
Authors: Ahmad Shanei, Mohammad Mahdi Shanei
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When a liquid is irradiated with high intensities (> 1 W) and low frequencies (≤ 1 MHz) ultrasound, acoustic cavitation occurs. Acoustic cavitation generates free radicals from the breakdown of water and other molecules. The existence of particles in liquid provide nucleation sites for cavitation bubbles and lead to decrease the ultrasonic intensity threshold needed for cavitation onset. The study was designed to measure hydroxyl radicals in terephthalic acid solutions containing 30 nm gold nanoparticles in a near field of a 1 MHz sonotherapy probe. The effect of ultrasound irradiation parameters containing mode of sonication and ultrasound intensity in hydroxyl radicals production have been investigated by the spectrofluorometry method. Recorded fluorescence signal in terephthalic acid solution containing gold nanoparticles was higher than the terephthalic acid solution without gold nanoparticles. Also, the results showed that any increase in intensity of the sonication would be associated with an increase in the fluorescence intensity. Acoustic cavitation in the presence of gold nanoparticles has been introduced as a way for improving therapeutic effects on the tumors. Also, the terephthalic acid dosimetry is suitable for detecting and quantifying free hydroxyl radicals as a criterion of cavitation production over a range of condition in medical ultrasound fields.Keywords: acoustic cavitation, gold nanoparticle, chemical dosimetry, terephthalic acid
Procedia PDF Downloads 470895 Analysis of Thermal Damping in Si Based Torsional Micromirrors
Authors: R. Resmi, M. R. Baiju
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The thermal damping of a dynamic vibrating micromirror is an important factor affecting the design of MEMS based actuator systems. In the development process of new micromirror systems, assessing the extent of energy loss due to thermal damping accurately and predicting the performance of the system is very essential. In this paper, the depth of the thermal penetration layer at different eigenfrequencies and the temperature variation distributions surrounding a vibrating micromirror is analyzed. The thermal penetration depth corresponds to the thermal boundary layer in which energy is lost which is a measure of the thermal damping is found out. The energy is mainly dissipated in the thermal boundary layer and thickness of the layer is an important parameter. The detailed thermoacoustics is used to model the air domain surrounding the micromirror. The thickness of the boundary layer, temperature variations and thermal power dissipation are analyzed for a Si based torsional mode micromirror. It is found that thermal penetration depth decreases with eigenfrequency and hence operating the micromirror at higher frequencies is essential for reducing thermal damping. The temperature variations and thermal power dissipations at different eigenfrequencies are also analyzed. Both frequency-response and eigenfrequency analyses are done using COMSOL Multiphysics software.Keywords: Eigen frequency analysis, micromirrors, thermal damping, thermoacoustic interactions
Procedia PDF Downloads 363894 Supplemental VisCo-friction Damping for Dynamical Structural Systems
Authors: Sharad Singh, Ajay Kumar Sinha
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Coupled dampers like viscoelastic-frictional dampers for supplemental damping are a newer technique. In this paper, innovative Visco-frictional damping models have been presented and investigated. This paper attempts to couple frictional and fluid viscous dampers into a single unit of supplemental dampers. Visco-frictional damping model is developed by series and parallel coupling of frictional and fluid viscous dampers using Maxwell and Kelvin-Voigat models. The time analysis has been performed using numerical simulation on an SDOF system with varying fundamental periods, subject to a set of 12 ground motions. The simulation was performed using the direct time integration method. MATLAB programming tool was used to carry out the numerical simulation. The response behavior has been analyzed for the varying time period and added damping. This paper compares the response reduction behavior of the two modes of coupling. This paper highlights the performance efficiency of the suggested damping models. It also presents a mathematical modeling approach to visco-frictional dampers and simultaneously suggests the suitable mode of coupling between the two sub-units.Keywords: hysteretic damping, Kelvin model, Maxwell model, parallel coupling, series coupling, viscous damping
Procedia PDF Downloads 157893 Identification of Switched Reluctance Motor Parameters Using Exponential Swept-Sine Signal
Authors: Abdelmalek Ouannou, Adil Brouri, Laila Kadi, Tarik
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Switched reluctance motor (SRM) has a major interest in a large domain as in electric vehicle driving because of its wide range of speed operation, high performances, low cost, and robustness to run under degraded conditions. The purpose of the paper is to develop a new analytical approach for modeling SRM parameters. Then, an identification scheme is proposed to obtain the SRM parameters. Since the SRM is featured by a highly nonlinear behavior, modeling these devices is difficult. Then, it is convenient to develop an accurate model describing the SRM. Furthermore, it is always operated in the magnetically saturated mode to maximize the energy transfer. Accordingly, it is shown that the SRM can be accurately described by a generalized polynomial Hammerstein model, i.e., the parallel connection of several Hammerstein models having polynomial nonlinearity. Presently an analytical identification method is developed using a chirp excitation signal. Afterward, the parameters of the obtained model have been determined using Finite Element Method analysis. Finally, in order to show the effectiveness of the proposed method, a comparison between the true and estimate models has been performed. The obtained results show that the output responses are very close.Keywords: switched reluctance motor, swept-sine signal, generalized Hammerstein model, nonlinear system
Procedia PDF Downloads 234892 An Interactive Platform Displaying Mixed Reality Media
Authors: Alfred Chen, Cheng Chieh Hsu, Yu-Pin Ma, Meng-Jie Lin, Fu Pai Chiu, Yi-Yan Sie
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This study is attempted to construct a human-computer interactive platform system that has mainly consisted of an augmented hardware system, a software system, a display table, and mixed media. This system has provided with human-computer interaction services through an interactive platform for the tourism industry. A well designed interactive platform, integrating of augmented reality and mixed media, has potential to enhance museum display quality and diversity. Besides, it will create a comprehensive and creative display mode for most museums and historical heritages. Therefore, it is essential to let public understand what the platform is, how it functions, and most importantly how one builds an interactive augmented platform. Hence the authors try to elaborate the construction process of the platform in detail. Thus, there are three issues to be considered, i.e.1) the theory and application of augmented reality, 2) the hardware and software applied, and 3) the mixed media presented. In order to describe how the platform works, Courtesy Door of Tainan Confucius Temple has been selected as case study in this study. As a result, a developed interactive platform has been presented by showing the physical entity object, along with virtual mixing media such as text, images, animation, and video. This platform will result in providing diversified and effective information that will be delivered to the users.Keywords: human-computer interaction, mixed reality, mixed media, tourism
Procedia PDF Downloads 488891 High-Accuracy Satellite Image Analysis and Rapid DSM Extraction for Urban Environment Evaluations (Tripoli-Libya)
Authors: Abdunaser Abduelmula, Maria Luisa M. Bastos, José A. Gonçalves
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The modeling of the earth's surface and evaluation of urban environment, with 3D models, is an important research topic. New stereo capabilities of high-resolution optical satellites images, such as the tri-stereo mode of Pleiades, combined with new image matching algorithms, are now available and can be applied in urban area analysis. In addition, photogrammetry software packages gained new, more efficient matching algorithms, such as SGM, as well as improved filters to deal with shadow areas, can achieve denser and more precise results. This paper describes a comparison between 3D data extracted from tri-stereo and dual stereo satellite images, combined with pixel based matching and Wallis filter. The aim was to improve the accuracy of 3D models especially in urban areas, in order to assess if satellite images are appropriate for a rapid evaluation of urban environments. The results showed that 3D models achieved by Pleiades tri-stereo outperformed, both in terms of accuracy and detail, the result obtained from a Geo-eye pair. The assessment was made with reference digital surface models derived from high-resolution aerial photography. This could mean that tri-stereo images can be successfully used for the proposed urban change analyses.Keywords: 3D models, environment, matching, pleiades
Procedia PDF Downloads 328890 Integrating a Six Thinking Hats Approach Into the Prewriting Stage of Argumentative Writing In English as a Foreign Language: A Chinese Case Study of Generating Ideas in Action
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Argumentative writing is the most prevalent genre in diverse writing tests. How to construct academic arguments is often regarded as a difficult task by most English as a foreign language (EFL) learners. A failure to generate enough ideas and organise them coherently and logically as well as a lack of competence in supporting their arguments with relevant evidence are frequent problems faced by EFL learners when approaching an English argumentative writing task. Overall, these problems are closely related to planning, and planning an argumentative writing at pre-writing stage plays a vital role in a good academic essay. However, how teachers can effectively guide students to generate ideas is rarely discussed in planning English argumentative writing, apart from brainstorming. Brainstorming has been a common practice used by teachers to help students generate ideas. However, some limitations of brainstorming suggest that it can help students generate many ideas, but ideas might not necessarily be coherent and logic, and could sometimes impede production. It calls for a need to explore effective instructional strategies at pre-writing stage of English argumentative writing. This paper will first examine how a Six Thinking Hats approach can be used to provide a dialogic space for EFL learners to experience and collaboratively generate ideas from multiple perspectives at pre-writing stage. Part of the findings of the impact of a twelve-week intervention (from March to July 2021) on students learning to generate ideas through engaging in group discussions of using Six Thinking Hats will then be reported. The research design is based on the sociocultural theory. The findings present evidence from a mixed-methods approach and fifty-nine participants from two first-year undergraduate natural classes in a Chinese university. Analysis of pre- and post- questionnaires suggests that participants had a positive attitude toward the Six Thinking Hats approach. It fosters their understanding of prewriting and argumentative writing, helps them to generate more ideas not only from multiple perspectives but also in a systematic way. A comparison of participants writing plans confirms an improvement in generating counterarguments and rebuttals to support their arguments. Above all, visual and transcripts data of group discussion collected from different weeks throughout the intervention enable teachers and researchers to ‘see’ the hidden process of learning to generate ideas in action.Keywords: argumentative writing, innovative pedagogy, six thinking hats, dialogic space, prewriting, higher education
Procedia PDF Downloads 86889 The Presence of Anglicisms in Italian Fashion Magazines and Fashion Blogs
Authors: Vivian Orsi
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The present research investigates the lexicon of a fashion magazine, whose universe is very receptive to lexical loans, especially those from English, called Anglicisms. Specifically, we intend to discuss the presence of English items and expressions in the Vogue Italia fashion magazine. Besides, we aim to study the anglicisms used in an Italian fashion blog called The Blonde Salad. Within the discussion of fashion blogs and their contributions to scientific studies, we adopt the theories of Lexicology / Lexicography to define Anglicism (BIDERMAN, 2001), and the observation of its prestige in the Italian Language (ROGATO, 2008; BISETTO, 2003). According to the theoretical basis mentioned, we intend to make a brief analysis of the Anglicisms collected from posts of the first year of existence of such fashion blog, emphasizing also the keywords that have the role to encapsulate the content of the text, allowing the reader to retrieve information from the post of the blog. About the use of English in Italian magazines and blogs, we can affirm that it seems to represent sophistication, assuming the value of prerequisite to participate in the fashion centers of the world. Besides, we believe, as Barthes says (1990, p. 215), that “Fashion does not evolve, it changes: its lexicon is new each year, like that of a language which always keeps the same system but suddenly and regularly ‘changes’ the currency of its words”. Fashion is a mode of communication: it is present in man's interaction with the world, which means that such lexical universe is represented according to the particularities of each culture.Keywords: anglicism, lexicology, magazines, blogs, fashion
Procedia PDF Downloads 331888 4-Channel CWDM Optical Transceiver Applying Silicon Photonics Ge-Photodiode and MZ-Modulator
Authors: Do-Won Kim, Andy Eu Jin Lim, Raja Muthusamy Kumarasamy, Vishal Vinayak, Jacky Wang Yu-Shun, Jason Liow Tsung Yang, Patrick Lo Guo Qiang
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In this study, we demonstrate 4-channel coarse wavelength division multiplexing (CWDM) optical transceiver based on silicon photonics integrated circuits (PIC) of waveguide Ge-photodiode (Ge-PD) and Mach Zehnder (MZ)-modulator. 4-channel arrayed PICs of Ge-PD and MZ-modulator are verified to operate at 25 Gbps/ch achieving 4x25 Gbps of total data rate. 4 bare dies of single-channel commercial electronics ICs (EICs) of trans-impedance amplifier (TIA) for Ge-PD and driver IC for MZ-modulator are packaged with PIC on printed circuit board (PCB) in a chip-on-board (COB) manner. Each single-channel EIC is electrically connected to the one channel of 4-channel PICs by wire bonds to trace. The PICs have 4-channel multiplexer for MZ-modulator and 4-channel demultiplexer for Ge-PD. The 4-channel multiplexer/demultiplexer have echelle gratings for4 CWDM optic signals of which center wavelengths are 1511, 1531, 1553, and 1573 nm. Its insertion loss is around 4dB with over 15dB of extinction ratio.The dimension of 4-channel Ge-PD is 3.6x1.4x0.3mm, and its responsivity is 1A/W with dark current of less than 20 nA.Its measured 3dB bandwidth is around 20GHz. The dimension of the 4-channel MZ-modulator is 3.6x4.8x0.3mm, and its 3dB bandwidth is around 11Ghz at -2V of reverse biasing voltage. It has 2.4V•cmbyVπVL of 6V for π shift to 4 mm length modulator.5x5um of Inversed tapered mode size converter with less than 2dB of coupling loss is used for the coupling of the lensed fiber which has 5um of mode field diameter.The PCB for COB packaging and signal transmission is designed to have 6 layers in the hybrid layer structure. 0.25 mm-thick Rogers Duroid RT5880 is used as the first core dielectric layer for high-speed performance over 25 Gbps. It has 0.017 mm-thick of copper layers and its dielectric constant is 2.2and dissipation factor is 0.0009 at 10 GHz. The dimension of both single ended and differential microstrip transmission lines are calculated using full-wave electromagnetic (EM) field simulator HFSS which RF industry is using most. It showed 3dB bandwidth at around 15GHz in S-parameter measurement using network analyzer. The wire bond length for transmission line and ground connection from EIC is done to have less than 300 µm to minimize the parasitic effect to the system.Single layered capacitors (SLC) of 100pF and 1000pF are connected as close as possible to the EICs for stabilizing the DC biasing voltage by decoupling. Its signal transmission performance is under measurement at 25Gbps achieving 100Gbps by 4chx25Gbps. This work can be applied for the active optical cable (AOC) and quad small form-factor pluggable (QSFP) for high-speed optical interconnections. Its demands are quite large in data centers targeting 100 Gbps, 400 Gbps, and 1 Tbps. As the demands of high-speed AOC and QSFP for the application to intra/inter data centers increase, this silicon photonics based high-speed 4 channel CWDM scheme can have advantages not only in data throughput but also cost effectiveness since it reduces fiber cost dramatically through WDM.Keywords: active optical cable(AOC), 4-channel coarse wavelength division multiplexing (CWDM), communication system, data center, ge-photodiode, Mach Zehnder (MZ) modulator, optical interconnections, optical transceiver, photonics integrated circuits (PIC), quad small form-factor pluggable (QSFP), silicon photonics
Procedia PDF Downloads 417887 Copper Related Toxicity of 1-Hydroxy-2-Thiopyridines
Authors: Elena G. Salina, Vadim A. Makarov
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With the emergence of primary resistance to the current drugs and wide distribution of latent tuberculosis infection, a need for new compounds with a novel mode of action is growing steadily. Copper-mediated innate immunity and antibacterial toxicity propose novel strategies in TB drug discovery and development. Transcriptome of M. tuberculosis was obtained by RNA-seq, intracellular copper content was measured by ISP MS and complexes of 1-hydroxy-2-thiopyridines with copper were detected by HPLC.1-hydroxy-2-thiopyridine derivatives were found to be highly active in vitro against both actively growing and dormant non-culturable M. tuberculosis. Transcriptome response to 1-hydroxy-2-thiopyridines revealed signs of copper toxicity in M. tuberculosis bacilli. Indeed, Cu was found to accumulate inside cells treated with 1-hydroxy-2-thiopyridines. These compounds were found to form stable charged lipophylic complexes with Cu²⁺ ions which transport into mycobacterial cell. Subsequent metabolic destruction of the complex led to transformation of 1-hydroxy-2-thiopyridines into 2-methylmercapto-2-ethoxycarbonylpyridines, which did not possess antitubercular activity and releasing of free Cu²⁺ in the cytoplasm. 1-hydroxy-2-thiopyridines are a potent class of Cu-dependent inhibitors of M. tuberculosis which may control M. tuberculosis infection by impairment of copper homeostasis. Acknowledgment: This work was financially supported by the Ministry of Education and Science of the RussianFederation (Agreement No 14.616.21.0065; unique identifier RFMEFI61616X0065).Keywords: copper toxicity, drug discovery, M. tuberculosis inhibitors, 2-thiopyridines
Procedia PDF Downloads 167886 The Phatic Function and the Socializing Element of Personal Blogs
Authors: Emelia Noronha, Milind Malshe
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The phatic function of communication is a vital element of any conversation. This research paper looks into this function with respect to personal blogs maintained by Indian bloggers. This paper is a study into the phenomenon of phatic communication maintained by bloggers through their blogs. Based on a linguistic analysis of the posts of twenty eight Indian bloggers, writing in English, studied over a period of three years, the study indicates that though the blogging phenomenon is not conversational in the same manner as face-to-face communication, it does make ample provision for feedback that is conversational in nature. Ordinary day to day offline conversations use conventionalized phatic utterances; those on the social media are in a perpetual mode of innovation and experimentation in order to sustain contact with its readers. These innovative methods and means are the focus of this study. Though the personal blogger aims to chronicle his/her personal life through the blog, the socializing function is crucial to these bloggers. In comparison to the western personal blogs which focus on the presentation of the ‘bounded individual self’, we find Indian personal bloggers engage in the presentation of their ‘social selves’. These bloggers yearn to reach out to the readers on the internet and the phatic function serves to initiate, sustain and renew social ties on the blogosphere thereby consolidating the social network of readers and bloggers.Keywords: personal blogs, phatic, social-selves, blog readers
Procedia PDF Downloads 359885 Multiple Intelligences as Basis for Differentiated Classroom Instruction in Technology Livelihood Education: An Impact Analysis
Authors: Sheila S. Silang
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This research seeks to make an impact analysis on multiple intelligence as the basis for differentiated classroom instruction in TLE. It will also address the felt need of how TLE subject could be taught effectively exhausting all the possible means.This study seek the effect of giving different instruction according to the ability of the students in the following objectives: 1. student’s technological skills enhancement, 2. learning potential improvements 3. having better linkage between school and community in a need for soliciting different learning devices and materials for the learner’s academic progress. General Luna, Quezon is composed of twenty seven barangays. There are only two public high schools. We are aware that K-12 curriculum is focused on providing sufficient time for mastery of concepts and skills, develop lifelong learners, and prepare graduates for tertiary education, middle-level skills development, employment, and entrepreneurship. The challenge is with TLE offerring a vast area of specializations, how would Multiple Intelligence play its vital role as basis in classroom instruction in acquiring the requirement of the said curriculum? 1.To what extent do the respondent students manifest the following types of intelligences: Visual-Spatial, Body-Kinesthetic, Musical, Interpersonal, Intrapersonal, Verbal-Linguistic, Logical-Mathematical and Naturalistic. What media should be used appropriate to the student’s learning style? Visual, Printed Words, Sound, Motion, Color or Realia 3. What is the impact of multiple intelligence as basis for differentiated instruction in T.L.E. based on the following student’s ability? Learning Characteristic and Reading Ability and Performance 3. To what extent do the intelligences of the student relate with their academic performance? The following were the findings derived from the study: In consideration of the vast areas of study of TLE, and the importance it plays in the school curriculum coinciding with the expectation of turning students to technologically competent contributing members of the society, either in the field of Technical/Vocational Expertise or Entrepreneurial based competencies, as well as the government’s concern for it, we visualize TLE classroom teachers making use of multiple intelligence as basis for differentiated classroom instruction in teaching the subject .Somehow, multiple intelligence sample such as Linguistic, Logical-Mathematical, Bodily-Kinesthetic, Interpersonal, Intrapersonal, and Spatial abilities that an individual student may have or may not have, can be a basis for a TLE teacher’s instructional method or design.Keywords: education, multiple, differentiated classroom instruction, impact analysis
Procedia PDF Downloads 445884 Cancer of the Cervix Caused by HPV (Human papillomavirus) in Algerian Population
Authors: Sara Mouffouk, Fatma Belaid, Asma Hechani, Chaima Mouffouk
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Cancer of the cervix caused by HPV (human papillomavirus ) is for many years a real public health problem, it is ranked 2nd deadly female cancer kills more than 270 000 women each year worldwide. In Algeria, the mortality of cervical cancer decreases with the impact, but the prognosis of these cancers remains bleak: The 5-year relative survival is 60 %. The mode of transmission is usually sexuel. Our study was undertaken to show the link between HPV and cervical cancer and the importance of Pap smear screening in this type of pathology. On the total sample, 76.11 % showed abnormal cervical smears of which 13% have mild cases and hormonal reaction Change, and 44% represent inflammatory smears and normal cases 35%, while long seven years from 2005 to 2012. Thus, 43% of abnormal smear results between ASCUS, AGUS, low and high grade carcinoma and adenocarcinoma and 57 % of other cases of unknown origin. The average age of women at risk of developing adenocarcinoma is 45-50 with a 67% to 33% of the same risk in women of age group 41-45 years although the percentage of cases of HPV infected patients was 2% in the past seven years. We found that with increasing age, the risk is argued. Due to several factors such as multiparty can reduced the resistance of the uterine epithelium and even as the multi that promotes contamination HPV causes repeated infections with HPV.Keywords: cervical cancer, human papillomavirus (HPV) screening, prevention, vaccines
Procedia PDF Downloads 515883 Removal of Mixed Heavy Metals from Contaminated Clay Soils Using Pulsed Electrokinetic Process
Authors: Nuhu Dalhat Mu’azu, Abdullahi Usman, A. Bukhari, Muhammad Hussain Essa, Salihu Lukman
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Electrokinetic remediation process was employed for the removal of four (4) heavy metals (Cr, Cu, Hg and Pb) from contaminated clay and bentonite soils under pulsed current supply mode. The effects of voltage gradient, pulse duty cycle and bentonite/clay ratio on the simultaneous removal efficiencies of the heavy metals were investigated. A total of thirteen experiments were designed and conducted according to factorial design with each experiment allowed to continuously ran for 3 weeks. Results obtained showed that increase in bentonite ratio decreased the removal efficiency of the heavy metals with no significant effect on the energy consumption. Conversely, increase in both voltage gradient and pulse duty cycle increased the heavy metals removal efficiencies with increased in energy consumption. Additionally, increase in voltage gradient increased the electrical conductivity and the soil pH due to due to continuous refill and replacement of process fluids as they decomposed under the induced voltage gradient. Under different operating conditions, the maximum removal efficiencies obtained for Cr, Cu, Hg, and Pb were 21.87, 83.2, 62.4, 78.06 and 16.65% respectively.Keywords: clay, bentonite, soil remediation, mixed contaminants, heavy metals, and electrokinetic-adsorption
Procedia PDF Downloads 428882 A Holographic Infotainment System for Connected and Driverless Cars: An Exploratory Study of Gesture Based Interaction
Authors: Nicholas Lambert, Seungyeon Ryu, Mehmet Mulla, Albert Kim
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In this paper, an interactive in-car interface called HoloDash is presented. It is intended to provide information and infotainment in both autonomous vehicles and ‘connected cars’, vehicles equipped with Internet access via cellular services. The research focuses on the development of interactive avatars for this system and its gesture-based control system. This is a case study for the development of a possible human-centred means of presenting a connected or autonomous vehicle’s On-Board Diagnostics through a projected ‘holographic’ infotainment system. This system is termed a Holographic Human Vehicle Interface (HHIV), as it utilises a dashboard projection unit and gesture detection. The research also examines the suitability for gestures in an automotive environment, given that it might be used in both driver-controlled and driverless vehicles. Using Human Centred Design methods, questions were posed to test subjects and preferences discovered in terms of the gesture interface and the user experience for passengers within the vehicle. These affirm the benefits of this mode of visual communication for both connected and driverless cars.Keywords: gesture, holographic interface, human-computer interaction, user-centered design
Procedia PDF Downloads 310881 Influence of the 3D Printing Parameters on the Dynamic Characteristics of Composite Structures
Authors: Ali Raza, Rūta Rimašauskienė
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In the current work, the fused deposition modelling (FDM) technique is used to manufacture PLA reinforced with carbon fibre composite structures with two unique layer patterns, 0°\0° and 0°\90°. The purpose of the study is to investigate the dynamic characteristics of each fabricated composite structure. The Macro Fiber Composite (MFC) is embedded with 0°/0° and 0°/90° structures to investigate the effect of an MFC (M8507-P2 type) patch on vibration amplitude suppression under dynamic loading circumstances. First, modal analysis testing was performed using a Polytec 3D laser vibrometer to identify bending mode shapes, natural frequencies, and vibration amplitudes at the corresponding natural frequencies. To determine the stiffness of each structure, several loads were applied at the free end of the structure, and the deformation was recorded using a laser displacement sensor. The findings confirm that a structure with 0°\0° layers pattern was found to have more stiffness compared to a 0°\90° structure. The maximum amplitude suppression in each structure was measured using a laser displacement sensor at the first resonant frequency when the control voltage signal with optimal phase was applied to the MFC. The results confirm that the 0°/0° pattern's structure exhibits a higher displacement reduction than the 0°/90° pattern. Moreover, stiffer structures have been found to perform amplitude suppression more effectively.Keywords: carbon fibre composite, MFC, modal analysis stiffness, stiffness
Procedia PDF Downloads 62880 Digital Publics, Analogue Institutions: Everyday Urban Politics in Gated Neighborhoods in India
Authors: Praveen Priyadarshi
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What is the nature of the 'political subjects' in the new urban spaces of the Indian cities? How do they become a 'public'? The paper explores these questions by studying the National Capital Region's gated communities in India. Even as the 'gated-ness' of these neighborhoods constantly underlines the definitive spatial boundary of the 'public' that it is constituted within the walls of a particular gated community, the making of this 'public' occurs as much in the digital spaces—in the digital space of online messaging apps and platforms—populated by unique digital identities. It is through constant exchanges of the digital identities that the 'public' is created. However, the institutional framework and the formal rules governing the making of the public are still analogue because they presume and privilege traditional modes of participation for people to constitute a 'public'. The institutions are designed as rules and norms governing people's behavior when they participate in traditional, physical mode, whereas rules and norms designed in the algorithms regulate people's social and political behavior in the digital domain. In exploring this disjuncture between the analogue institutions and the digital public, the paper analytically evaluates the nature of everyday politics in gates neighborhoods in India.Keywords: gated communities, everyday politics, new urban spaces, digital publics
Procedia PDF Downloads 163879 Agent-Based Modeling of Pedestrian Corridor Congestion on the Characteristics of Physical Space Form
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The pedestrian corridor is the most crowded area in the public space. The crowded severity has been focused on the field of evacuation strategies of the entrance in large public spaces. The aim of this paper is to analyze the walking efficiency in different spaces of pedestrian corridor with the variation of spatial parameters. The congestion condition caused by the variation of walking efficiency is modeled as well. This study established the space model of the walking corridor by setting the width, slope, turning form and turning angle of the pedestrian corridor. The pedestrian preference of walking mode varied with the difference of the crowded severity, walking speed, field of vision, sight direction and the expected destination, which is influenced by the characters of physical space form. Swarm software is applied to build Agent model. According to the output of the Agent model, the relationship between the pedestrian corridor width, ground slope, turning forms, turning angle and the walking efficiency, crowded severity is acquired. The results of the simulation can be applied to pedestrian corridor design in order to reduce the crowded severity and the potential safety risks caused by crowded people.Keywords: crowded severity, multi-agent, pedestrian preference, urban space design
Procedia PDF Downloads 217878 Experimental Modal Analysis of Kursuncular Minaret
Authors: Yunus Dere
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Minarets are tower like structures where the call to prayer of Muslims is performed. They have a symbolic meaning and sacred place among Muslims. Being tall and slender, they are prone to damage under earthquakes and strong winds. Kursuncular stone minaret was built around thirty years ago in Konya/TURKEY. Its core and helical stairs are made of reinforced concrete. Its stone spire was damaged during a light earthquake. Its spire is later replaced with a light material covered with lead sheets. In this study, the natural frequencies and mode shapes of Kursuncular minaret is obtained experimentally and analytically. First an ambient vibration test is carried out using a data acquisition system with accelerometers located at four locations along the height of the minaret. The collected vibration data is evaluated by operational modal analysis techniques. For the analytical part of the study, the dimensions of the minaret are accurately measured and a detailed 3D solid finite element model of the minaret is generated. The moduli of elasticity of the stone and concrete are approximated using the compressive strengths obtained by Windsor Pin tests. Finite element modal analysis of the minaret is carried out to get the modal parameters. Experimental and analytical results are then compared and found in good agreement.Keywords: experimental modal analysis, stone minaret, finite element modal analysis, minarets
Procedia PDF Downloads 325877 Quasi-Static Analysis of End Plate Beam-to-Column Connections
Authors: A. Al-Rifaie, Z. W. Guan, S. W. Jones
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This paper presents a method for modelling and analysing end plate beam-to-column connections to obtain the quasi-static behaviour using non-linear dynamic explicit integration. In addition to its importance to study the static behaviour of a structural member, quasi-static behaviour is largely needed to be compared with the dynamic behaviour of such members in order to investigate the dynamic effect by proposing dynamic increase factors (DIFs). The beam-to-column bolted connections contain various contact surfaces at which the implicit procedure may have difficulties converging, resulting in a large number of iterations. Contrary, explicit procedure could deal effectively with complex contacts without converging problems. Hence, finite element modelling using ABAQUS/explicit is used in this study to address the dynamic effect may be produced using explicit procedure. Also, the effect of loading rate and mass scaling are discussed to investigate their effect on the time of analysis. The results show that the explicit procedure is valuable to model the end plate beam-to-column connections in terms of failure mode, load-displacement relationships. Also, it is concluded that loading rate and mass scaling should be carefully selected to avoid the dynamic effect in the solution.Keywords: quasi-static, end plate, finite elements, connections
Procedia PDF Downloads 305