Search results for: Term Frequency-Inverse Document Frequency (TF-IDF)
1583 Application of Artificial Neural Networks for Temperature Forecasting
Authors: Mohsen Hayati, Zahra Mohebi
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In this paper, the application of neural networks to study the design of short-term temperature forecasting (STTF) Systems for Kermanshah city, west of Iran was explored. One important architecture of neural networks named Multi-Layer Perceptron (MLP) to model STTF systems is used. Our study based on MLP was trained and tested using ten years (1996-2006) meteorological data. The results show that MLP network has the minimum forecasting error and can be considered as a good method to model the STTF systems.Keywords: Artificial neural networks, Forecasting, Weather, Multi-layer perceptron.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 43571582 A Performance Evaluation of Cellular Network Suitability for VANET
Authors: Ho-Yeon Kim, Dong-Min Kang, Jun-Ho Lee, Tai-Myoung Chung
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Recently, a vehicular ad-hoc networks(VANETs) for Intelligent Transport System(ITS) have become able safety and convenience services surpassing the simple services such as an electronic toll collection system. To provide the proper services, VANET needs infrastructure over the country infrastructure. Thus, we have to spend a huge sum of human resources. In this reason, several studies have been made on the usage of cellular networks instead of new protocols this study is to assess a performance evaluation of the cellular network for VANET. In this paper, the result of a for the suitability of cellular networks for VANET experiment, The LTE(Long Term Evolution) of cellular networks found to be most suitable among the others cellular networksKeywords: Vehicle communication, VANET, Cellular network
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27151581 Rock Textures Classification Based on Textural and Spectral Features
Authors: Tossaporn Kachanubal, Somkait Udomhunsakul
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In this paper, we proposed a method to classify each type of natural rock texture. Our goal is to classify 26 classes of rock textures. First, we extract five features of each class by using principle component analysis combining with the use of applied spatial frequency measurement. Next, the effective node number of neural network was tested. We used the most effective neural network in classification process. The results from this system yield quite high in recognition rate. It is shown that high recognition rate can be achieved in separation of 26 stone classes.Keywords: Texture classification, SFM, neural network, rock texture classification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20101580 Comparison of the Existing Methods in Determination of the Characteristic Polynomial
Authors: Mohammad Saleh Tavazoei, Mohammad Haeri
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This paper presents comparison among methods of determination of the characteristic polynomial coefficients. First, the resultant systems from the methods are compared based on frequency criteria such as the closed loop bandwidth, gain and phase margins. Then the step responses of the resultant systems are compared on the basis of the transient behavior criteria including overshoot, rise time, settling time and error (via IAE, ITAE, ISE and ITSE integral indices). Also relative stability of the systems is compared together. Finally the best choices in regards to the above diverse criteria are presented.Keywords: Characteristic Polynomial, Transient Response, Filters, Stability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20141579 Improved K-Modes for Categorical Clustering Using Weighted Dissimilarity Measure
Authors: S.Aranganayagi, K.Thangavel
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K-Modes is an extension of K-Means clustering algorithm, developed to cluster the categorical data, where the mean is replaced by the mode. The similarity measure proposed by Huang is the simple matching or mismatching measure. Weight of attribute values contribute much in clustering; thus in this paper we propose a new weighted dissimilarity measure for K-Modes, based on the ratio of frequency of attribute values in the cluster and in the data set. The new weighted measure is experimented with the data sets obtained from the UCI data repository. The results are compared with K-Modes and K-representative, which show that the new measure generates clusters with high purity.
Keywords: Clustering, categorical data, K-Modes, weighted dissimilarity measure
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 36901578 Multiple Positive Periodic Solutions of a Competitor-Competitor-Mutualist Lotka-Volterra System with Harvesting Terms
Authors: Yongkun Li, Erliang Xu
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In this paper, by using Mawhin-s continuation theorem of coincidence degree theory, we establish the existence of multiple positive periodic solutions of a competitor-competitor-mutualist Lotka-Volterra system with harvesting terms. Finally, an example is given to illustrate our results.
Keywords: Positive periodic solutions, competitor-competitor mutualist Lotka-Volterra systems, coincidence degree, harvesting term.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13531577 Existence of Multiple Positive Periodic Solutions to n Species Nonautonomous Lotka-Volterra Cooperative Systems with Harvesting Terms
Authors: Kaihong Zhao
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In this paper, the existence of 2n positive periodic solutions for n species non-autonomous Lotka-Volterra cooperative systems with harvesting terms is established by using Mawhin-s continuation theorem of coincidence degree theory and matrix inequality. An example is given to illustrate the effectiveness of our results.
Keywords: Multiple positive periodic solutions, Nonautonomous Lotka-Volterra cooperative system, Coincidence degree, Harvesting term.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13371576 An 880 / 1760 MHz Dual Bandwidth Active RC Filter for 60 GHz Applications
Authors: Sanghoon Park, Kijin Kim, Kwangho Ahn
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An active RC filters with a 880 / 1760 MHz dual bandwidth tuning ability is present for 60 GHz unlicensed band applications. A third order Butterworth low-pass filter utilizes two Cherry-Hooper amplifiers to satisfy the very high bandwidth requirements of an amplifier. The low-pass filter is fabricated in 90nm standard CMOS process. Drawing 6.7 mW from 1.2 V power supply, the low frequency gains of the filter are -2.5 and -4.1 dB, and the output third order intercept points (OIP3) are +2.2 and +1.9 dBm for the single channel and channel bonding conditions, respectively.
Keywords: Butterworth filter, active RC, 60 GHz, CMOS, dual bandwidth, Cherry-Hooper amplifier.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22281575 Study on Radio Link Availability in Millimeter Wave Range
Authors: Boncho G. Bonev, Kliment N. Angelov, Emil S. Altimirski
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In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth-s atmosphere. Based on statistical rain rates data for Bulgaria, the link availability can be determined, depending on the working frequency, the path length and the Power Budget of the link. For the calculations of rain attenuation and atmosphere-s attenuation the ITU recommendations are used.Keywords: rain attenuation, atmospheric gaseous attenuation, link availability, link breaking probability
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20241574 Comparative Performance Analysis of Nonlinearity Cancellation Techniques for MOS-C Realization in Integrator Circuits
Authors: Hasan Çiçekli, Ahmet Gökçen, Uğur Çam
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In this paper, a comparative performance analysis of mostly used four nonlinearity cancellation techniques used to realize the passive resistor by MOS transistors, is presented. The comparison is done by using an integrator circuit which is employing sequentially Op-amp, OTRA and ICCII as active element. All of the circuits are implemented by MOS-C realization and simulated by PSPICE program using 0.35μm process TSMC MOSIS model parameters. With MOS-C realization, the circuits became electronically tunable and fully integrable which is very important in IC design. The output waveforms, frequency responses, THD analysis results and features of the nonlinearity cancellation techniques are also given.Keywords: Integrator circuits, MOS-C realization, nonlinearity cancellation, tunable resistors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21161573 Application of a Dual Satellite Geolocation System on Locating Sweeping Interference
Authors: M. H. Chan
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This paper describes an application of a dual satellite geolocation (DSG) system on identifying and locating the unknown source of uplink sweeping interference. The geolocation system integrates the method of joint time difference of arrival (TDOA) and frequency difference of arrival (FDOA) with ephemeris correction technique which successfully demonstrated high accuracy in interference source location. The factors affecting the location error were also discussed.Keywords: Dual satellite geolocation system, DGS, geolocation, TDOA/FDOA, and sweeping interference
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 40401572 Slaughter and Carcass Characterization, and Sensory Qualities of Native, Pure, and Upgraded Breeds of Goat Raised in the Philippines
Authors: Jonathan N. Nayga, Emelita B. Valdez, Mila R. Andres, Beulah B. Estrada, Emelina A. Lopez, Rogelio B. Tamayo, Aubrey Joy M. Balbin
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Goat production is one of the activities included in integrated farming in the Philippines. Goats are raised for its meat and regardless of breed the animal is slaughtered for this purpose. In order to document the carcass yield of different goats slaughtered, five (5) different breeds of goats to include Purebred Boer and Anglo-nubian, Crossbred Boer and Anglo-nubian and Philippine Native goat were used in the study. Data on slaughter parameters, carcass characteristics, and sensory evaluation were gathered and analyzed using Complete Random Design (CRD) at 5% level of significance and the results of carcass conformation were assessed descriptively. Results showed that slaughter data such as slaughter/live weight, hot and chilled carcass weights, dressing percentage and percentage drip loss were significantly different (P>0.05) among breeds. On carcass and meat characteristics, pure breed and upgraded Boer were found to be moderately muscular while Native goat was rated as thin muscular. The color of the carcass also revealed that Purebred and crossbred Boer were described dark red, while Native goat was noted to be slightly pale. On sensory evaluation, the results indicated that there was no significant difference (P>0.05) among breeds evaluated. It is therefore concluded that purebred goat has heavier carcass, while both purebred Boer and upgrade are rated slightly muscular. It is further confirms that regardless of breed, goat will have the same sensory characteristics. Thus, it is recommended to slaughter heavier goats to obtain more carcasses with better conformation and quality.Keywords: Carcass quality, goat, sensory evaluation, slaughter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20371571 Robust Stabilization against Unknown Consensus Network
Authors: Myung-Gon Yoon, Jung-Ho Moon, Tae Kwon Ha
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This paper studies a robust stabilization problem of a single agent in a multi-agent consensus system composed of identical agents, when the network topology of the system is completely unknown. It is shown that the transfer function of an agent in a consensus system can be described as a multiplicative perturbation of the isolated agent transfer function in frequency domain. From an existing robust stabilization result, we present sufficient conditions for a robust stabilization of an agent against unknown network topology.
Keywords: Multi-agent System, Robust Stabilization, Transfer Function.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18701570 Climatic Change, Drought and Dust Crisis in Iran
Authors: Akram Keramat, Behrouz Marivani, Mehdi Samsami
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Drought is a phenomenon caused by environmental and climatic changes. This phenomenon is affected by shortage of rainfall and temperature. Dust is one of important environmental problems caused by climate change and drought. With recent multi-year drought, many environmental crises caused by dust in Iran and Middle East. Dust in the vast areas of the provinces occurs with high frequency. By dust affecting many problems created in terms of health, social and economic. In this study, we tried to study the most important factors causing dust. In this way we have used the satellite images and meteorological data. Finally, strategies to deal with the dust will be mentioned.Keywords: Drought, Environment, Dust.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 36431569 Nonlinear Stability of Convection in a Thermally Modulated Anisotropic Porous Medium
Authors: M. Meenasaranya, S. Saravanan
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Conditions corresponding to the unconditional stability of convection in a mechanically anisotropic fluid saturated porous medium of infinite horizontal extent are determined. The medium is heated from below and its bounding surfaces are subjected to temperature modulation which consists of a steady part and a time periodic oscillating part. The Brinkman model is employed in the momentum equation with the Bousinessq approximation. The stability region is found for arbitrary values of modulational frequency and amplitude using the energy method. Higher order numerical computations are carried out to find critical boundaries and subcritical instability regions more accurately.Keywords: Convection, porous medium, anisotropy, temperature modulation, nonlinear stability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8741568 RFID Logistic Management with Cold Chain Monitoring – Cold Store Case Study
Authors: Mira Trebar
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Logistics processes of perishable food in the supply chain include the distribution activities and the real time temperature monitoring to fulfil the cold chain requirements. The paper presents the use of RFID (Radio Frequency Identification) technology as an identification tool of receiving and shipping activities in the cold store. At the same time, the use of RFID data loggers with temperature sensors is presented to observe and store the temperatures for the purpose of analyzing the processes and having the history data available for traceability purposes and efficient recall management.
Keywords: Logistics, warehouse, RFID device, cold chain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37151567 Harmonic Reduction In Three-Phase Parallel Connected Inverter
Authors: M.A.A. Younis, N. A. Rahim, S. Mekhilef
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This paper presents the design and analysis of a parallel connected inverter configuration of. The configuration consists of parallel connected three-phase dc/ac inverter. Series resistors added to the inverter output to maintain same current in each inverter of the two parallel inverters, and to reduce the circulating current in the parallel inverters to the minimum. High frequency third harmonic injection PWM (THIPWM) employed to reduce the total harmonic distortion and to make maximum use of the voltage source. DSP was used to generate the THIPWM and the control algorithm for the converter. Selected experimental results have been shown to validate the proposed system.Keywords: Three-phase inverter, Third harmonic injection PWM, inverters parallel connection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37751566 Changes in Fine PM Pollution Levels with Tightening of Regulations on Vehicle Emissions
Authors: Akihiro Iijima, Kimiyo Kumagai
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A long-term campaign for monitoring the concentration of atmospheric Particulate Matter (PM) was conducted at multiple sites located in the center and suburbs of the Tokyo Metropolitan Area in Japan. The concentration of fine PM has shown a declining trend over the last two decades. A positive matrix factorization model elucidated that the contribution of combustion sources was drastically reduced. In Japan, the regulations on vehicle exhaust emissions were phased in and gradually tightened over the last two decades, which has triggered a notable reduction in PM emissions from automobiles and has contributed to the mitigation of the problem of fine PM pollution.Keywords: Air pollution, Diesel-powered vehicle, Positive matrix factorization, Receptor modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17651565 Capacity Building for Hazmat Transport Emergency Preparedness: 'Hotspot Impact Zone' Mapping from Flammable and Toxic Releases
Authors: U K Chakrabarti, Jigisha Parikh
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Hazardous Material transportation by road is coupled with inherent risk of accidents causing loss of lives, grievous injuries, property losses and environmental damages. The most common type of hazmat road accident happens to be the releases (78%) of hazardous substances, followed by fires (28%), explosions (14%) and vapour/ gas clouds (6 %.). The paper is discussing initially the probable 'Impact Zones' likely to be caused by one flammable (LPG) and one toxic (ethylene oxide) chemicals being transported through a sizable segment of a State Highway connecting three notified Industrial zones in Surat district in Western India housing 26 MAH industrial units. Three 'hotspots' were identified along the highway segment depending on the particular chemical traffic and the population distribution within 500 meters on either sides. The thermal radiation and explosion overpressure have been calculated for LPG / Ethylene Oxide BLEVE scenarios along with toxic release scenario for ethylene oxide. Besides, the dispersion calculations for ethylene oxide toxic release have been made for each 'hotspot' location and the impact zones have been mapped for the LOC concentrations. Subsequently, the maximum Initial Isolation and the protective zones were calculated based on ERPG-3 and ERPG-2 values of ethylene oxide respectively which are estimated taking the worst case scenario under worst weather conditions. The data analysis will be helpful to the local administration in capacity building with respect to rescue / evacuation and medical preparedness and quantitative inputs to augment the District Offsite Emergency Plan document.Keywords: Hotspot, Ethylene Oxide, LPG, MAH (MajorAccident Hazard).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18051564 Quartz Crystal Microbalance Based Hydrophobic Nanosensor for Lysozyme Detection
Authors: F. Yilmaz, Y. Saylan, A. Derazshamshir, S. Atay, A. Denizli
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A quartz crystal microbalance (QCM) nanosensor was developed to detect lysozyme enzyme by functionalizing its gold surface with the attachment of poly(methacroyl-L-phenylalanine) (PMAPA) nanoparticles. PMAPA was chosen as a hydrophobic matrix. The hydrophobic nanoparticles were synthesized by micro-emulsion polymerization method. Hydrophobic QCM nanosensor was tested for real time detection of lysozyme enzyme from aqueous solution. The kinetic and affinity studies were determined by using lysozyme solutions with different concentrations. The responses related with mass (Δm) and frequency (Δf) shifts were used to evaluate adsorption properties.
Keywords: HIC, lysozyme, nanosensor, QCM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21721563 Antenna for Energy Harvesting in Wireless Connected Objects
Authors: Nizar Sakli, Chayma Bahar, Chokri Baccouch, Hedi Sakli
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If connected objects multiply, they are becoming a challenge in more than one way. In particular by their consumption and their supply of electricity. A large part of the new generations of connected objects will only be able to develop if it is possible to make them entirely autonomous in terms of energy. Some manufacturers are therefore developing products capable of recovering energy from their environment. Vital solutions in certain contexts, such as the medical industry. Energy recovery from the environment is a reliable solution to solve the problem of powering wireless connected objects. This paper presents and study a optically transparent solar patch antenna in frequency band of 2.4 GHz for connected objects in the future standard 5G for energy harvesting and RF transmission.Keywords: 5G, IoT, wireless communications, antenna, solar cell.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8161562 Implementation of Second Order Current- Mode Quadrature Sinusoidal Oscillator with Current Controllability
Authors: Koson Pitaksuttayaprot, Winai Jaikla
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The realization of current-mode quadrature oscillators using current controlled current conveyor transconductance amplifiers (CCCCTAs) and grounded capacitors is presented. The proposed oscillators can provide 2 sinusoidal output currents with 90º phase difference. It is enabled non-interactive dual-current control for both the condition of oscillation and the frequency of oscillation. High output impedances of the configurations enable the circuit to be cascaded without additional current buffers. The use of only grounded capacitors is ideal for integration. The circuit performances are depicted through PSpice simulations, they show good agreement to theoretical anticipation.Keywords: Current-mode, Oscillator, Integrated circuit, CCCCTA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19071561 Classification of Right and Left-Hand Movement Using Multi-Resolution Analysis Method
Authors: Nebi Gedik
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The aim of the brain-computer interface studies on electroencephalogram (EEG) signals containing motor imagery is to extract the effective features that will provide the highest possible classification accuracy for the detection of the desired motor movement. However, achieving this goal is difficult as the most suitable frequency band and time frame vary from subject to subject. In this study, the classification success of the two-feature data obtained from raw EEG signals and the coefficients of the multi-resolution analysis method applied to the EEG signals were analyzed comparatively. The method was applied to several EEG channels (C3, Cz and C4) signals obtained from the EEG data set belonging to the publicly available BCI competition III.
Keywords: Motor imagery, EEG, wave atom transform, k-NN.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5901560 A Digitally Programmable Voltage-mode Multifunction Biquad Filter with Single-Output
Authors: C. Ketviriyakit, W. Kongnun, C. Chanapromma, P. Silapan
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This article proposes a voltage-mode multifunction filter using differential voltage current controllable current conveyor transconductance amplifier (DV-CCCCTA). The features of the circuit are that: the quality factor and pole frequency can be tuned independently via the values of capacitors: the circuit description is very simple, consisting of merely 1 DV-CCCCTA, and 2 capacitors. Without any component matching conditions, the proposed circuit is very appropriate to further develop into an integrated circuit. Additionally, each function response can be selected by suitably selecting input signals with digital method. The PSpice simulation results are depicted. The given results agree well with the theoretical anticipation.Keywords: DV-CCCCTA, Voltage-mode, Multifunction filter
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13591559 The Correlation between Peer Aggression and Peer Victimization: Are Aggressors Victims Too?
Authors: Glenn M. Calaguas
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To investigate the possible correlation between peer aggression and peer victimization, 148 sixth-graders were asked to respond to the Reduced Aggression and Victimization Scales (RAVS). RAVS measures the frequency of reporting aggressive behaviors or of being victimized during the previous week prior to the survey. The scales are composed of six items each. Each point represents one instance of aggression or victimization. Specifically, the Pearson Product-Moment Correlation Coefficient (PMCC) was used to determine the correlations between the scores of the sixthgraders in the two scales, both in individual items and total scores. Positive correlations were established and correlations were significant at the 0.01 levels.
Keywords: correlation, peer aggression, peer victimization, sixth-graders.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24451558 Minimum Data of a Speech Signal as Special Indicators of Identification in Phonoscopy
Authors: Nazaket Gazieva
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Voice biometric data associated with physiological, psychological and other factors are widely used in forensic phonoscopy. There are various methods for identifying and verifying a person by voice. This article explores the minimum speech signal data as individual parameters of a speech signal. Monozygotic twins are believed to be genetically identical. Using the minimum data of the speech signal, we came to the conclusion that the voice imprint of monozygotic twins is individual. According to the conclusion of the experiment, we can conclude that the minimum indicators of the speech signal are more stable and reliable for phonoscopic examinations.
Keywords: Biometric voice prints, fundamental frequency, phonogram, speech signal, temporal characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5771557 A New Gateway for Rheumatoid Arthritis: COXIBs with an Improved Cardiovascular Profile
Authors: M. Hoxha, V. Capra, C. Buccellati, A. Sala, C. Cena, R. Fruttero, M. Bertinaria, G. E. Rovati
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Today COXIBs are used in the treatment of arthritis and many other painful conditions in selected patients with high gastrointestinal risk and low cardiovascular (CV) risk. Previously, we have identified an unexpected mechanism of action of a traditional non-steroidal anti-inflammatory drug (NSAID) (diclofenac) and a specific inhibitor of cyclooxygenase-2 (COXIB) (lumiracoxib) demonstrating that they possess weak competitive antagonism at the thromboxane receptor (TP). We hypothesize that modifying the structure of a known COXIB so that it becomes also a more potent TP antagonist will preserve the anti-inflammatory and gastrointestinal safety typical of COXIBs and prevent the CV risk associated with long term therapy.
Keywords: Cyclooxygenase, inflammation, lumiracoxib, thromboxane A2.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20431556 Health Effects of Trihalomethanes as Chlorinated Disinfection by Products: A Review Article
Authors: M. R. Mohamadshafiee, L. Taghavi
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Trihalomethanes (THMs) were among the first disinfection byproducts to be discovered in chlorinated water. The substances form during a reaction between chlorine and organic matter in the water. Trihalomethanes are suspected to have negative effects on birth such as, low birth weight, intrauterine growth retardation in term births, as well as gestational age and preterm delivery. There are also some evidences showing these by-products to be mutagenic and carcinogenic, the greatest amount of evidence being related to the bladder cancer. However, there exist inconsistencies regarding such effects of THMs as different studies have provided different results in this regard. The aim of the present study is to provide a review of the related researches about the above mentioned health effects of THMs.Keywords: Trihalomethans, by-products, disinfection, carcinogenic
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 47261555 Non-Stationary Stochastic Optimization of an Oscillating Water Column
Authors: María L. Jalón, Feargal Brennan
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A non-stationary stochastic optimization methodology is applied to an OWC (oscillating water column) to find the design that maximizes the wave energy extraction. Different temporal cycles are considered to represent the long-term variability of the wave climate at the site in the optimization problem. The results of the non-stationary stochastic optimization problem are compared against those obtained by a stationary stochastic optimization problem. The comparative analysis reveals that the proposed non-stationary optimization provides designs with a better fit to reality. However, the stationarity assumption can be adequate when looking at averaged system response.Keywords: Non-stationary stochastic optimization, oscillating water column, temporal variability, wave energy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13801554 Effect of Field Dielectric Material on Performance of InGaAs Power LDMOSFET
Authors: Yashvir Singh, Swati Chamoli
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In this paper, a power laterally-diffused metal-oxide-semiconductor field-effect transistor (LDMOSFET) on In0.53Ga0.47As is presented. The device utilizes a thicker field-oxide with low dielectric constant under the field-plate in order to achieve possible reduction in device capacitances and reduced-surface-field effect. Using 2D numerical simulations, performance of the proposed device is analyzed and compared with that of the conventional LDMOSFET. The proposed structure provides 50% increase in the breakdown voltage, 21% increase in transit frequency, and 72% improvement in figure-of-merit over the conventional device for same cell pitch.
Keywords: InGaAs, dielectric, lateral, power MOSFET.
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