Search results for: frequency diversity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5569

Search results for: frequency diversity

2959 Torsional Vibration of Carbon Nanotubes via Nonlocal Gradient Theories

Authors: Mustafa Arda, Metin Aydogdu

Abstract:

Carbon nanotubes (CNTs) have many possible application areas because of their superior physical properties. Nonlocal Theory, which unlike the classical theories, includes the size dependency. Nonlocal Stress and Strain Gradient approaches can be used in nanoscale static and dynamic analysis. In the present study, torsional vibration of CNTs was investigated according to nonlocal stress and strain gradient theories. Effects of the small scale parameters to the non-dimensional frequency were obtained. Results were compared with the Molecular Dynamics Simulation and Lattice Dynamics. Strain Gradient Theory has shown more weakening effect on CNT according to the Stress Gradient Theory. Combination of both theories gives more acceptable results rather than the classical and stress or strain gradient theory according to Lattice Dynamics.

Keywords: torsional vibration, carbon nanotubes, nonlocal gradient theory, stress, strain

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2958 Effects of IPPC Permits on Ambient Air Quality

Authors: C. Cafaro, P. Ceci, L. De Giorgi

Abstract:

The aim of this paper is to give an assessment of environmental effects of IPPC permit conditions of installations that are in the specific territory with a high concentration of industrial activities. The IPPC permit is the permit that each operator should hold to operate the installation as stated by the directive 2010/75/UE on industrial emissions (integrated pollution prevention and control), known as IED (Industrial Emissions Directive). The IPPC permit includes all the measures necessary to achieve a high level of protection of the environment as a whole, also defining the monitoring requirements as measurement methodology, frequency, and evaluation procedure. The emissions monitoring of a specific plant may also give indications of the contribution of these emissions on the air quality of a definite area. So, it is clear that the IPPC permits are important tools both to improve the environmental framework and to achieve the air quality standards, assisting in assessing the possible industrial sources contributions to air pollution.

Keywords: IPPC, IED, emissions, permits, air quality, large combustion plants

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2957 Consensus Problem of High-Order Multi-Agent Systems under Predictor-Based Algorithm

Authors: Cheng-Lin Liu, Fei Liu

Abstract:

For the multi-agent systems with agent's dynamics described by high-order integrator, and usual consensus algorithm composed of the state coordination control parts is proposed. Under communication delay, consensus algorithm in asynchronously-coupled form just can make the agents achieve a stationary consensus, and sufficient consensus condition is obtained based on frequency-domain analysis. To recover the original consensus state of the high-order agents without communication delay, besides, a predictor-based consensus algorithm is constructed via multiplying the delayed neighboring agents' states by a delay-related compensation part, and sufficient consensus condition is also obtained. Simulation illustrates the correctness of the results.

Keywords: high-order dynamic agents, communication delay, consensus, predictor-based algorithm

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2956 OMTHD Strategy in Asymmetrical Seven-Level Inverter for High Power Induction Motor

Authors: Rachid Taleb, M’hamed Helaimi, Djilali Benyoucef, Ahmed Derrouazin

Abstract:

Multilevel inverters are well used in high power electronic applications because of their ability to generate a very good quality of waveforms, reducing switching frequency, and their low voltage stress across the power devices. This paper presents the Optimal Minimization of the Total Harmonic Distortion (OMTHD) strategy of a uniform step asymmetrical seven-level inverter (USA7LI). The OMTHD approach is compared to the well-known sinusoidal pulse-width modulation (SPWM) strategy. Simulation results demonstrate the better performances and technical advantages of the OMTHD controller in feeding a High Power Induction Motor (HPIM).

Keywords: uniform step asymmetrical seven-level inverter (USA7LI), optimal minimization of the THD (OMTHD), sinusoidal PWM (SPWM), high power induction motor (HPIM)

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2955 An Investigation of Thai Passengers’ Level of Understanding and Awareness: Cabin Crew Safety Briefing

Authors: Chantarat Manvichien, Kevin Wongleedee

Abstract:

The purpose of this research was to study Thai passengers’ level of understanding and awareness of the cabin crew safety briefing in the airplane during the preparation to take off and landing. It is important to know if Thai passengers pay attention to cabin crew safety briefing and to suggest a better way to draw their attention. The independent variables included gender, age, income, levels of education, travelling purpose, and travelling frequency while the dependent variables was level of awareness. A simple random sampling method was utilized to get 400 respondents. The findings revealed the ranking the first three levels of importance by highest mean to lowest mean as follows: (1) It is important to listen to cabin crew safety briefing; (2) Cabin crew briefing is interesting; (3) Information from cabin crew safety briefing is easy to understand. In addition, the overall means was 3.27 with 0.800 SD.

Keywords: cabin crew, safety briefing, Thai passengers, awareness

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2954 Nosocomial Infections and Prevention in in Intensive Care Units and Intensive Care

Authors: Kaous Samira

Abstract:

The lack of hand hygiene can contribute to nosocomial infections, including Central-venous-catheter-related bloodstream infections (CRBSI). An investigation from severally hospitals examined the frequency of hand hygiene in an OR among perioperative staff members who did not perform a surgical scrub. Among 50 operations (120 hours) that were observed, only 2% of staff members performed hand hygiene practices upon entering the OR, and 8.4% of staff performed hand hygiene upon leaving the OR. In addition, when performing radial arterial catheter placement, 0% of staff members wore gloves. Another study (A1170) surveyed healthcare providers regarding hand hygiene compliance. All of the 107 providers surveyed agreed that they should maintain hand hygiene, and most respondents believed that their own compliance was high. The author suggests that the low compliance problem associated with hand hygiene worldwide is a behavioral one among healthcare providers that requires acknowledgment and change.

Keywords: aneshesia, investigation, IOP, SBP

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2953 Overview of Wireless Body Area Networks

Authors: Rashi Jain

Abstract:

The Wireless Body Area Networks (WBANs) is an emerging interdisciplinary area where small sensors are placed on/within the human body. These sensors monitor the physiological activities and vital statistics of the body. The data from these sensors is aggregated and communicated to a remote doctor for immediate attention or to a database for records. On 6 Feb 2012, the IEEE 802.15.6 task group approved the standard for Body Area Network (BAN) technologies. The standard proposes the physical and MAC layer for the WBANs. The work provides an introduction to WBANs and overview of the physical and MAC layers of the standard. The physical layer specifications have been covered. A comparison of different protocols used at MAC layer is drawn. An introduction to the network layer and security aspects of the WBANs is made. The WBANs suffer certain limitations such as regulation of frequency bands, minimizing the effect of transmission and reception of electromagnetic signals on the human body, maintaining the energy efficiency among others. This has slowed down their implementation.

Keywords: vehicular networks, sensors, MicroController 8085, LTE

Procedia PDF Downloads 244
2952 MHC Class II DRB1 Gene Polymorphism in Lori Sheep Breed

Authors: Shahram Nanekarani, Majid Goodarzi, Majid Khosravi

Abstract:

The present study aimed at analyzing of ovine major histocompatibility complex class II (Ovar II) DRB1 gene second exon in Lori Sheep breed. The MHC plays a central role in the control of disease resistance and immunological response. Genomic DNA from blood samples of 124 sheep was extracted and a 296 bp MHC exon 2 fragment was amplified using polymerase chain reaction. PCR products were characterized by the restriction fragment length polymorphism technique using Hin1I restriction enzyme. The PCRRFLP patterns showed three genotypes, AA, AB and BB with frequency of 0.282, 0.573 and 0.145, respectively. There was no significant (P > 0.05) deviation from Hardy–Weinberg equilibrium for this locus in this population. The results of the present study indicate that exon 2 of the Ovar-DRB1 gene is highly polymorphic in Lori sheep and could be considered as an important marker assisted selection, for improvement of immunity in sheep.

Keywords: MHC-DRB1 gene, polymorphism, PCR-RFLP, lori sheep

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2951 Competitive Strategy that Affect to the Competitive Advantage for Hotel and Resort in Samut Songkram Province

Authors: Phatthanan Chaiyabut

Abstract:

This research paper investigates whether the development of environmentally friendly practices by luxury hotel resorts can be used as a strategy for gaining competitive advantage through differentiation, and suggests ways to do it. The focus is on luxury hotel resorts in Samut Songkram Province, Thailand. A questionnaire was utilized as a tool to collect data. Statistics utilized in this research included frequency, percentage, mean, standard deviation, and multiple regression analysis. Findings indicate that environmentally friendly development of hotel resorts in Samut Songkram Province has a very limited use as a corporate strategy. Only two luxury hotel resorts had it incorporated in their strategy, it is not much used in marketing indicating environmental issues are not seen as important. This was confirmed through the interviews with the managers that it is not seen as important issue to promote.

Keywords: competitive advantage, competitive strategy, Samut Songkram Province, hotel and resort

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2950 Relationships between Motivation Factors and English Language Proficiency of the Faculty of Management Sciences Students

Authors: Kawinphat Lertpongmanee

Abstract:

The purposes of this study were (1) investigate the English language learning motivation and the attainment of their English proficiency, (2) to find out how motivation and motivational variables of the high and low proficiency subjects are related to their English proficiency. The respondents were 80 fourth-year from Faculty of Management Sciences students in Rajabhat Suansunadha University. The instruments used for data collection were questionnaires. The statistically analyzed by using the SPSS program for frequency, percentage, arithmetic mean, standard deviation (SD), t-test, one-way analysis of variance (ANOVA), and Pearson correlation coefficient. The findings of this study are summarized as there was a significant difference in overall motivation between high and low proficiency groups of subjects at .05 (p < .05), but not in overall motivational variables. Additionally, the high proficiency group had a significantly higher level of intrinsic motivation than did the low proficiency group at .05 (p < .05).

Keywords: English language proficiency, faculty of management sciences, motivation factors, proficiency subjects

Procedia PDF Downloads 248
2949 Antifungal Susceptibility of Yeasts Isolated from Clinical Samples from a Tertiary Hospital from State of Puebla

Authors: Ricardo Munguia-Perez, Nayeli Remigio-Alvarado, M.Miriam Hernandez-Arroyo, Elsa Castañeda-Roldan

Abstract:

Fungi have emerged as important pathogens causing morbidity and mortality mainly in immunosuppressed, malnourished and elderly patients. It has detected an increase in resistance to azoles primarily to fluconazol. The fungal infections have become a problem of public health for the resistance to antifungal agents, they have developed new antifungals with broad-spectrum. The aim of this study was determine the antifungal susceptibility of yeasts isolated from clinical samples (respiratory secretions, exudates, wounds, blood cultures, urine cultures) obtained from inpatients and outpatients of a tertiary hospital from State of Puebla. The antifungal susceptibility of the yeast from several clinical samples were determined by the CLS M44-A disk diffusion methods. 149 samples of yeast were analyzed. All species were 100% susceptible to nystatin and amphotericin B. Candida albicans showed resistance of 95.5 % to fluconazole, 50.7 % to 5-flurocytosine and 55.2 % intermediate susceptibility to ketoconazole. Candida glabrata 81.3 % was susceptibility to ketoconazole and 75 % to fluconazole, for the case of 5-flurocytosine the 56.3 % was susceptible. Candida krusei 100 % was susceptible to ketoconazole, 50 % to fluconazole and 37.5 % to 5-flurocytosine. The internal medicine have greater diversity of yeast, the samples have susceptibility of 64.7% to ketoconazole, 47.1 % to fluconazole and 27.5 % to 5-flurocytosine. Hospitalized patients are more resistant to fluconazole and nystatin, but in the case of outpatients presents resistance to ketoconazole.

Keywords: antifungal, susceptibility, yeast, clinical samples

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2948 Lattice Network Model for Calculation of Eddy Current Losses in a Solid Permanent Magnet

Authors: Jan Schmidt, Pierre Köhring

Abstract:

Permanently excited machines are set up with magnets that are made of highly energetic magnetic materials. Inherently, the permanent magnets warm up while the machine is operating. With an increasing temperature, the electromotive force and hence the degree of efficiency decrease. The reasons for this are slot harmonics and distorted armature currents arising from frequency inverter operation. To prevent or avoid demagnetizing of the permanent magnets it is necessary to ensure that the magnets do not excessively heat up. Demagnetizations of permanent magnets are irreversible and a breakdown of the electrical machine is inevitable. For the design of an electrical machine, the knowledge of the behavior of heating under operating conditions of the permanent magnet is of crucial importance. Therefore, a calculation model is presented with which the machine designer can easily calculate the eddy current losses in the magnetic material.

Keywords: analytical model, eddy current, losses, lattice network, permanent magnet

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2947 Business Intelligence for Profiling of Telecommunication Customer

Authors: Rokhmatul Insani, Hira Laksmiwati Soemitro

Abstract:

Business Intelligence is a methodology that exploits the data to produce information and knowledge systematically, business intelligence can support the decision-making process. Some methods in business intelligence are data warehouse and data mining. A data warehouse can store historical data from transactional data. For data modelling in data warehouse, we apply dimensional modelling by Kimball. While data mining is used to extracting patterns from the data and get insight from the data. Data mining has many techniques, one of which is segmentation. For profiling of telecommunication customer, we use customer segmentation according to customer’s usage of services, customer invoice and customer payment. Customers can be grouped according to their characteristics and can be identified the profitable customers. We apply K-Means Clustering Algorithm for segmentation. The input variable for that algorithm we use RFM (Recency, Frequency and Monetary) model. All process in data mining, we use tools IBM SPSS modeller.

Keywords: business intelligence, customer segmentation, data warehouse, data mining

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2946 Crystalline Silicon Optical Whispering Gallery Mode (WGM) Resonators for Precision Measurements

Authors: Igor Bilenko, Artem Shitikov, Michael Gorodetsky

Abstract:

Optical whispering gallery mode (WGM) resonators combine very high optical quality factor (Q) with small size. Resonators made from low loss crystalline fluorites (CaF2, MgF2) may have Q as high as 1010 that make them unique devices for modern applications including ultrasensitive sensors, frequency control, and precision spectroscopy. While silicon is a promising material transparent from near infrared to terahertz frequencies, fundamental limit for Si WGM quality factor was not reached yet. In our paper, we presented experimental results on the preparation and testing of resonators at 1550 nm wavelength made from crystalline silicon grown and treated by different techniques. Q as high as 3x107 was demonstrated. Future steps need to reach a higher value and possible applications are discussed.

Keywords: optical quality factor, silicon optical losses, silicon optical resonator, whispering gallery modes

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2945 Analysis of Matching Pursuit Features of EEG Signal for Mental Tasks Classification

Authors: Zin Mar Lwin

Abstract:

Brain Computer Interface (BCI) Systems have developed for people who suffer from severe motor disabilities and challenging to communicate with their environment. BCI allows them for communication by a non-muscular way. For communication between human and computer, BCI uses a type of signal called Electroencephalogram (EEG) signal which is recorded from the human„s brain by means of an electrode. The electroencephalogram (EEG) signal is an important information source for knowing brain processes for the non-invasive BCI. Translating human‟s thought, it needs to classify acquired EEG signal accurately. This paper proposed a typical EEG signal classification system which experiments the Dataset from “Purdue University.” Independent Component Analysis (ICA) method via EEGLab Tools for removing artifacts which are caused by eye blinks. For features extraction, the Time and Frequency features of non-stationary EEG signals are extracted by Matching Pursuit (MP) algorithm. The classification of one of five mental tasks is performed by Multi_Class Support Vector Machine (SVM). For SVMs, the comparisons have been carried out for both 1-against-1 and 1-against-all methods.

Keywords: BCI, EEG, ICA, SVM

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2944 Improving the Quality of Casava Peel-Leaf Mixture through Fermentation with Rhizopus oligosporusas Poultry Ration

Authors: Mirnawati, G. Ciptaan, Ferawati

Abstract:

This study aims to improve the quality of the cassava peel-leaf mixture (CPLM) through fermentation with Rhizopus oligosporusas poultry ration. This research is an experimental study using a completely randomized design (CRD) with four treatments and five replications. The treatments were cassava peel-leaf mixture (CPLM) fermented with Rhizopus oligosporus. The treatments were a combination of cassava peel and leaves with the ratio of; A (9:1), B (8:2), C (7:3), and D (6:4). The observed variables were protease enzyme activity, crude protein, crude fiber, nitrogen retention, digestibility of crude fiber, and metabolic energy. The results of the diversity analysis showed that there was a very significant (p < 0.01) effect on protease activity, crude protein, crude fiber, nitrogen retention, digestibility of crude fiber, and energy metabolism of fermented CPLM. Based on the results of the study, it can be concluded that CPLM (6:4) fermented with Rhizopus oligosporus gave the best results seen from protease activity 7,25 U/ml, 21.23% crude protein, 19.80% crude fiber, 59.65% nitrogen retention, 62.99% crude fiber digestibility and metabolic energy 2671 Kcal/kg.

Keywords: quality, Casava peel-leaf mixture, fermentation, Rhizopus oligosporus

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2943 Bayesian Hidden Markov Modelling of Blood Type Distribution for COVID-19 Cases Using Poisson Distribution

Authors: Johnson Joseph Kwabina Arhinful, Owusu-Ansah Emmanuel Degraft Johnson, Okyere Gabrial Asare, Adebanji Atinuke Olusola

Abstract:

This paper proposes a model to describe the blood types distribution of new Coronavirus (COVID-19) cases using the Bayesian Poisson - Hidden Markov Model (BP-HMM). With the help of the Gibbs sampler algorithm, using OpenBugs, the study first identifies the number of hidden states fitting European (EU) and African (AF) data sets of COVID-19 cases by blood type frequency. The study then compares the state-dependent mean of infection within and across the two geographical areas. The study findings show that the number of hidden states and infection rates within and across the two geographical areas differ according to blood type.

Keywords: BP-HMM, COVID-19, blood types, GIBBS sampler

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2942 Analysis of Thermoelectric Coolers as Energy Harvesters for Low Power Embedded Applications

Authors: Yannick Verbelen, Sam De Winne, Niek Blondeel, Ann Peeters, An Braeken, Abdellah Touhafi

Abstract:

The growing popularity of solid state thermoelectric devices in cooling applications has sparked an increasing diversity of thermoelectric coolers (TECs) on the market, commonly known as “Peltier modules”. They can also be used as generators, converting a temperature difference into electric power, and opportunities are plentiful to make use of these devices as thermoelectric generators (TEGs) to supply energy to low power, autonomous embedded electronic applications. Their adoption as energy harvesters in this new domain of usage is obstructed by the complex thermoelectric models commonly associated with TEGs. Low cost TECs for the consumer market lack the required parameters to use the models because they are not intended for this mode of operation, thereby urging an alternative method to obtain electric power estimations in specific operating conditions. The design of the test setup implemented in this paper is specifically targeted at benchmarking commercial, off-the-shelf TECs for use as energy harvesters in domestic environments: applications with limited temperature differences and space available. The usefulness is demonstrated by testing and comparing single and multi stage TECs with different sizes. The effect of a boost converter stage on the thermoelectric end-to-end efficiency is also discussed.

Keywords: thermoelectric cooler, TEC, complementary balanced energy harvesting, step-up converter, DC/DC converter, energy harvesting, thermal harvesting

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2941 Networked Implementation of Milling Stability Optimization with Bayesian Learning

Authors: Christoph Ramsauer, Jaydeep Karandikar, Tony Schmitz, Friedrich Bleicher

Abstract:

Machining stability is an important limitation to discrete part machining. In this work, a networked implementation of milling stability optimization with Bayesian learning is presented. The milling process was monitored with a wireless sensory tool holder instrumented with an accelerometer at the Vienna University of Technology, Vienna, Austria. The recorded data from a milling test cut is used to classify the cut as stable or unstable based on the frequency analysis. The test cut result is fed to a Bayesian stability learning algorithm at the University of Tennessee, Knoxville, Tennessee, USA. The algorithm calculates the probability of stability as a function of axial depth of cut and spindle speed and recommends the parameters for the next test cut. The iterative process between two transatlantic locations repeats until convergence to a stable optimal process parameter set is achieved.

Keywords: machining stability, machine learning, sensor, optimization

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2940 Structural Rehabilitation, Retrofitting and Strengthening of Reinforced Concrete Structures

Authors: Manish Kumar

Abstract:

Reinforced cement concrete is getting extensively used for construction of different type of structures for the last one century. During this period, we have constructed many structures like buildings, bridges, industrial structures, pavement, water tanks etc. using this construction material. These structures have been created with huge investment of resources. It is essential to maintain those structures in functional condition. Since deterioration in RCC Structures is a common and natural phenomenon it is required to have a detailed plan, methodology for structural repair and rehabilitation shall be in place for dealing such issues. It is important to know exact reason of distress, type of distress and correct method of repair concrete structures. The different methods of repair are described in paper according to distress category which can be refereed for repair. Major finding of the study is that to protect our structure we need to have maintenance frequency and correct material to be chosen for repair. Also workmanship during repair needs to be taken utmost care for quality repair.

Keywords: deterioration, functional condition, reinforced cement concrete, resources

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2939 Traveling Abroad and the Construction of British Identity and Culture in Selected Women Writers: Lady Elizabeth Craven's A Journey Through the Crimea to Constantinople (1789) and Lady Mary Wortley Montagu's Embassy Letters (1716-1718)

Authors: Raja Al-Khalili

Abstract:

Traveling abroad for British citizens in the eighteenth century was usually performed for two reasons. The first major form was for administering the expanding realm of the British Empire and its need for officials in governing the natives and facilitating the work of business companies. The other form of travel was for pleasure and involved a manifestation of wealth. This form of travel was a prelude for the modern industry of tourism and usually involved a tour of Europe and the Mediterranean. In both forms of travel the British encountered a myriad of cultures. Travel had fostered a sense of pride and confirmed an ethnocentric view of British superiority, but it also brought a critical self-examination of belonging to a colonial empire that thrives on the weaknesses of other nations. Women writers in particular have sought in the travels a kind of self-exploration of the nature of social patriarchy in a diversity of cultures. Both Lady Elizabeth Craven in A Journey through the Crimea to Constantinople (1789) and Lady Mary Wortley Montagu in Embassy Letters (1716-1718) have observed the culture of the Ottomans and then pursued to reflect on the social role of women in England.

Keywords: travel writing, Elizabeth Craven, Lady Mary Wortley, patriarchy

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2938 Optimal Site Selection for Temporary Housing regarding Disaster Management Case Study: Tehran Municipality (No.6)

Authors: Ghazaleh Monazami Tehrani, Zhamak Monazami Tehrani, Raziyeh Hadavand

Abstract:

Optimal site selection for temporary housing is one of the most important issues in crisis management. In this research, district six of Tehran city with high frequency and geographical distribution of earthquakes has been selected as a case study for positioning temporary housing after a probable earthquake. For achieving this goal this study tries to identify and evaluate distribution of location according to some standards such as compatible and incompatible urban land uses with utility of GIS and AHP. The results of this study show the most susceptible parts of this region in the center. According to the maps, north eastern part of Kordestan, Shaheed Gomnam intersection possesses the highest pixels value in terms of areal extent, therefore these places are recommended as an optimum site location for construction of emergency evacuation base.

Keywords: optimal site selection, temporary housing , crisis management, AHP, GIS

Procedia PDF Downloads 240
2937 Graphene Metamaterials Supported Tunable Terahertz Fano Resonance

Authors: Xiaoyong He

Abstract:

The manipulation of THz waves is still a challenging task due to lack of natural materials interacted with it strongly. Designed by tailoring the characters of unit cells (meta-molecules), the advance of metamaterials (MMs) may solve this problem. However, because of Ohmic and radiation losses, the performance of MMs devices is subjected to the dissipation and low quality factor (Q-factor). This dilemma may be circumvented by Fano resonance, which arises from the destructive interference between a bright continuum mode and dark discrete mode (or a narrow resonance). Different from symmetric Lorentz spectral curve, Fano resonance indicates a distinct asymmetric line-shape, ultrahigh quality factor, steep variations in spectrum curves. Fano resonance is usually realized through symmetry breaking. However, if concentric double rings (DR) are placed closely to each other, the near-field coupling between them gives rise to two hybridized modes (bright and narrowband dark modes) because of the local asymmetry, resulting into the characteristic Fano line shape. Furthermore, from the practical viewpoint, it is highly desirable requirement that to achieve the modulation of Fano spectral curves conveniently, which is an important and interesting research topics. For current Fano systems, the tunable spectral curves can be realized by adjusting the geometrical structural parameters or magnetic fields biased the ferrite-based structure. But due to limited dispersion properties of active materials, it is still a tough work to tailor Fano resonance conveniently with the fixed structural parameters. With the favorable properties of extreme confinement and high tunability, graphene is a strong candidate to achieve this goal. The DR-structure possesses the excitation of so-called “trapped modes,” with the merits of simple structure and high quality of resonances in thin structures. By depositing graphene circular DR on the SiO2/Si/ polymer substrate, the tunable Fano resonance has been theoretically investigated in the terahertz regime, including the effects of graphene Fermi level, structural parameters and operation frequency. The results manifest that the obvious Fano peak can be efficiently modulated because of the strong coupling between incident waves and graphene ribbons. As Fermi level increases, the peak amplitude of Fano curve increases, and the resonant peak position shifts to high frequency. The amplitude modulation depth of Fano curves is about 30% if Fermi level changes in the scope of 0.1-1.0 eV. The optimum gap distance between DR is about 8-12 μm, where the value of figure of merit shows a peak. As the graphene ribbon width increases, the Fano spectral curves become broad, and the resonant peak denotes blue shift. The results are very helpful to develop novel graphene plasmonic devices, e.g. sensors and modulators.

Keywords: graphene, metamaterials, terahertz, tunable

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2936 Effect of Blade Layout on Unidirectional Rotation of a Vertical-Axis Rotor in Waves

Authors: Yingchen Yang

Abstract:

Ocean waves are a rich renewable energy source that is nearly untapped to date, even though many wave energy conversion (WEC) technologies are currently under development. The present work discusses a vertical-axis WEC rotor for power generation. The rotor was specially designed to allow easy rearrangement of the same blades to achieve different rotor configurations and result in different wave-rotor interaction behaviors. These rotor configurations were tested in a wave tank under various wave conditions. The testing results indicate that all the rotor configurations perform unidirectional rotation about the vertical axis in waves, but the response characteristics are somewhat different. The rotor's unidirectional rotation about its vertical axis is essential in wave energy harvesting since it makes the rotor respond well in a wide range of the wave frequency and in any wave propagation directions. Result comparison among different configurations leads to a preferred rotor design for further hydrodynamic optimization.

Keywords: unidirectional rotation, vertical axis rotor, wave energy conversion, wave-rotor interaction

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2935 A new genus and species of Agriotina Laporte, 1840 (Coleoptera: Elateridae: Agriotini) from Colombia

Authors: Martin L. Zurita García, Erick O. Martínez Luque, Jessica Morales Perdomo, Yivy Martínez Duarte, Jorge Ari Noriega

Abstract:

Colombia’s click beetles (Family Elateridae) are poorly documented in their diversity and taxonomy. There are listed 43 genera for Colombia but without a specific number of their species. No species of the genus Agriotes Eschscholtz (Elaterinae: Agriotini) have been recorded in Colombia. Currently, the subtribe Agriotina in the New World includes three genera: Agriotes, Bohartina Arias and Dalopius Eschscholtz. Historically, the genera Agriotes and Dalopius have had significant taxonomic problems due to their morphological resemblance. These similarities motivated several specialists to generate taxonomic movements such as synonyms and segregations of species in these genera on several occasions. To trying to solve these taxonomic problems, an author proposes some morphological characters present in the larvae, but mainly some genital characters of the females, such as the sclerotized plates of the bursa copulatrix. After examining material newly collected in Colombia, we found a click beetle having a unique combination of diagnostic characters that clearly separate it from any other genera of Agriotina. Hence, we describe and illustrate this click beetle under the name Raphaellus deusminutosi Zurita-García, Morales-Perdomo & Martínez-Luque n. gen. & n. sp., and we also compare this genus with the other New World genera of the subtribes Agriotina.

Keywords: click beetles, new genus, new species, elaterinae, raphaellus deusminutosi

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2934 Guided Wave in a Cylinder with Trepezoid Cross-Section

Authors: Nan Tang, Bin Wu, Cunfu He

Abstract:

The trapezoid rods are widely used in civil engineering as load –carrying members. Ultrasonic guided wave is one of the most popular techniques in analyzing the propagation of elastic guided wave. The goal of this paper is to investigate the propagation of elastic waves in the isotropic bar with trapezoid cross-section. Dispersion curves that describe the relationship between the frequency and velocity provide the fundamental information to describe the propagation of elastic waves through a structure. Based on the SAFE (semi-analytical finite element) a linear algebraic system of equations is obtained. By using numerical methods, dispersion curves solved for the rods with the trapezoid cross-section. These fundamental information plays an important role in applying ultrasonic guided waves to NTD for structures with trapezoid cross section.

Keywords: guided wave, dispersion, finite element method, trapezoid rod

Procedia PDF Downloads 283
2933 The Power of Words: A Corpus Analysis of Campaign Speeches of President Donald J. Trump

Authors: Aiza Dalman

Abstract:

Words are powerful when these are used wisely and strategically. In this study, twelve (12) campaign speeches of President Donald J. Trump were analyzed as to frequently used words and ethos, pathos and logos being employed. The speeches were read thoroughly, analyzed and interpreted. With the use of Word Counter Tool and Text Analyzer software accessible online, it was found out that the word ‘will’ has the highest frequency of 121, followed by Hillary (58), American (38), going (35), plan and Clinton (32), illegal (30), government (28), corruption (26) and criminal (24). When the speeches were analyzed as to ethos, pathos and logos, on the other hand, it revealed that these were all employed in his speeches. The statements under these pointed out against Hillary or in his favor. The unique strategy of President Donald J. Trump as to frequently used words and ethos, pathos and logos in persuading people perhaps lead the way to his victory.

Keywords: campaign speeches, corpus analysis, ethos, logos and pathos, power of words

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2932 On Being a Fugitive from the State-Sponsored Witch Hunt of Homosexuals in Egypt's Media Discourse

Authors: Mahitab A. A. Mahmoud

Abstract:

Despite the international community’s galvanized efforts to achieve gender equality, the Arab world still lags behind for their sustained suppression of diversity and freedoms. In Egypt, homosexuals are defamed and hunted not only by authorities but also by politicized religious institutions and media platforms. The resultant state-sponsored homophobia is reflected in media. This paper offers a critical discourse analysis of the representation of LGBTQs in Egypt’s local news articles and movies in an attempt to investigate the underlying ideology. The results reveal a clichéd portrayal of homosexuals as a social parasite that requires cleansing by the government. LGBTQs are depicted as an outcome of debauchery, unhappy marriage, sexual deviancy, deficiency of masculinity/femininity, absence of the mother and/or father figure(s), abject poverty, excessive wealth, psychiatric disorder, debased instincts, childhood sexual molestation, immorality, deviation from religion, chaos, treason, conspiracy against the regime, to name only a few. This image, which is imposed and sustained by the state, exposes homosexuals to a violation of their human rights by both the police and the society, endangers their lives, breeds intolerance, social inequality and violence, prevents healthy coexistence; and deprives them of living a normal life.

Keywords: critical discourse analysis, gender studies, homophobia, homosexuality, ideology, media studies

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2931 Electrostatic and Dielectric Measurements for Hair Building Fibers from DC to Microwave Frequencies

Authors: K. Y. You, Y. L. Then

Abstract:

In the recent years, the hair building fiber has become popular, in other words, it is an effective method which helps people who suffer hair loss or sparse hair since the hair building fiber is capable to create a natural look of simulated hair rapidly. In the markets, there are a lot of hair fiber brands that have been designed to formulate an intense bond with hair strands and make the hair appear more voluminous instantly. However, those products have their own set of properties. Thus, in this report, some measurement techniques are proposed to identify those products. Up to five different brands of hair fiber are tested. The electrostatic and dielectric properties of the hair fibers are macroscopically tested using design DC and high-frequency microwave techniques. Besides, the hair fibers are microscopically analysis by magnifying the structures of the fiber using scanning electron microscope (SEM). From the SEM photos, the comparison of the uniformly shaped and broken rate of the hair fibers in the different bulk samples can be observed respectively.

Keywords: hair fiber, electrostatic, dielectric properties, broken rate, microwave techniques

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2930 Flexible Design of Triboelectric Nanogenerators for Efficient Vibration Energy Harvesting

Authors: Meriam Khelifa

Abstract:

In recent years, many studies have focused on the harvesting of the vibrations energy to produce electrical energy using contact separation (CS) triboelectric nanogenerators (TENG). The simplest design for a TENG consists of a capacitor comprising a single moving electrode. The conversion efficiency of vibration energy into electrical energy can, in principle, reach 100%. But to actually achieve this objective, it is necessary to optimize the parameters of the TENG, such as the dielectric constant and the thickness of the insulator, the load resistance, etc. In particular, the use of a switch which is actioned at optimal times within the TENG cycle is essential. Using numerical modeling and experimental design, we applied a methodology to find the TENG parameters which optimize the energy transfer efficiency (ETE) to almost 100% for any vibration frequency and amplitude. The rather simple design of a TENG is promising as an environment friendly device. It opens the doors for harvesting acoustic vibrations from the environment and to design effective protection against environmental noise.

Keywords: vibrations, CS TENG, efficiency, design of experiments

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