Search results for: frequency oscillation damping (FOD)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4350

Search results for: frequency oscillation damping (FOD)

1290 Design and Development of Compact 1KW Floating Battery Discharge Regulator

Authors: A. Sreedevi, G. Anantaramu

Abstract:

The present space research organizations are striving towards the development of lighter, smaller, more efficient, low cost, and highly reliable power supply. Switch mode power supplies (SMPS) overcome the demerits of linear power supplies such as low efficiency, difficulties in thermal management, and in boosting the output voltage. Space applications require a constant DC voltage to supply its load. As the load varies, the battery terminal voltage tends to vary accordingly. To avoid this variation in the load terminal voltage, a DC-DC regulator is required. The conventional regulator for space applications is isolated boost topology. The proposed topology uses an interleaved push-pull converter with a current doubler secondary to reduce the EMI issues and increase efficiency. The proposed topology uses a floating technique where the converter derives power from the battery and generates only the voltage that is required to fill the gap between the bus and the battery voltage. The direct voltage sense and current loop provide tight regulation of output and better stability. Converter is designed with 50 kHz switching frequency using UC 1825 PWM controller employing both voltage and peak current mode control. Experimental tests have been carried out on the converter under different input and load conditions to validate the design. The experimental results showed that the efficiency was greater than 91%. Stability analysis is done using venable stability analyzer.

Keywords: push pull converter, current doubler, converter, PWM control

Procedia PDF Downloads 105
1289 Detection and Classification of Mammogram Images Using Principle Component Analysis and Lazy Classifiers

Authors: Rajkumar Kolangarakandy

Abstract:

Feature extraction and selection is the primary part of any mammogram classification algorithms. The choice of feature, attribute or measurements have an important influence in any classification system. Discrete Wavelet Transformation (DWT) coefficients are one of the prominent features for representing images in frequency domain. The features obtained after the decomposition of the mammogram images using wavelet transformations have higher dimension. Even though the features are higher in dimension, they were highly correlated and redundant in nature. The dimensionality reduction techniques play an important role in selecting the optimum number of features from the higher dimension data, which are highly correlated. PCA is a mathematical tool that reduces the dimensionality of the data while retaining most of the variation in the dataset. In this paper, a multilevel classification of mammogram images using reduced discrete wavelet transformation coefficients and lazy classifiers is proposed. The classification is accomplished in two different levels. In the first level, mammogram ROIs extracted from the dataset is classified as normal and abnormal types. In the second level, all the abnormal mammogram ROIs is classified into benign and malignant too. A further classification is also accomplished based on the variation in structure and intensity distribution of the images in the dataset. The Lazy classifiers called Kstar, IBL and LWL are used for classification. The classification results obtained with the reduced feature set is highly promising and the result is also compared with the performance obtained without dimension reduction.

Keywords: PCA, wavelet transformation, lazy classifiers, Kstar, IBL, LWL

Procedia PDF Downloads 335
1288 Clinical Impact of Ultra-Deep Versus Sanger Sequencing Detection of Minority Mutations on the HIV-1 Drug Resistance Genotype Interpretations after Virological Failure

Authors: S. Mohamed, D. Gonzalez, C. Sayada, P. Halfon

Abstract:

Drug resistance mutations are routinely detected using standard Sanger sequencing, which does not detect minor variants with a frequency below 20%. The impact of detecting minor variants generated by ultra-deep sequencing (UDS) on HIV drug-resistance (DR) interpretations has not yet been studied. Fifty HIV-1 patients who experienced virological failure were included in this retrospective study. The HIV-1 UDS protocol allowed the detection and quantification of HIV-1 protease and reverse transcriptase variants related to genotypes A, B, C, E, F, and G. DeepChek®-HIV simplified DR interpretation software was used to compare Sanger sequencing and UDS. The total time required for the UDS protocol was found to be approximately three times longer than Sanger sequencing with equivalent reagent costs. UDS detected all of the mutations found by population sequencing and identified additional resistance variants in all patients. An analysis of DR revealed a total of 643 and 224 clinically relevant mutations by UDS and Sanger sequencing, respectively. Three resistance mutations with > 20% prevalence were detected solely by UDS: A98S (23%), E138A (21%) and V179I (25%). A significant difference in the DR interpretations for 19 antiretroviral drugs was observed between the UDS and Sanger sequencing methods. Y181C and T215Y were the most frequent mutations associated with interpretation differences. A combination of UDS and DeepChek® software for the interpretation of DR results would help clinicians provide suitable treatments. A cut-off of 1% allowed a better characterisation of the viral population by identifying additional resistance mutations and improving the DR interpretation.

Keywords: HIV-1, ultra-deep sequencing, Sanger sequencing, drug resistance

Procedia PDF Downloads 336
1287 Effects of Aging on Ultra: Triathlon Performance

Authors: Richard S. Jatau, Kankanala Venkateswarlu, Bulus Kpame

Abstract:

The purpose of this critical review is to find out what is known and what is unknown about the effects of aging on endurance performance, especially on ultra- triathlon performance. It has been shown that among master’s athlete’s peak levels of performance decreased by 50% by age 50 it has also been clearly revealed that age associated atrophy, weakness and fatigability cannot be halted, although year round athletic training can slow down this age associated decline. Studies have further revealed that 30% to 50% decrease in skeletal muscle mass between ages 40 and 80 years, which is accompanied by an equal or even greater decline in strength and power and an increase in muscle weakness and fatigability. Studies on ultra- triathlon athletes revealed that 30 to 39 year old showed fastest time, with athletes in younger and older age groups were slower. It appears that the length of the endurance performance appears to influence age related endurance performance decline in short distance triathlons. A significant decline seems to start at the age of 40 to 50 years, whereas in long distance triathlons this decline seems to start after the age of 65 years. However, it is not clear whether this decline is related in any way to the training methods used, the duration of training, or the frequency of training. It’s also not clear whether the triathlon athletes experience more injuries due to long hours of training. It’s also not clear whether these athletes used performance enhancing drugs to enhance their performance. It’s not also clear whiles there has been tremendous increase in the number of athletes specializing in triathlon. On the basis of our experience and available research evidence we have provided answers to some of these questions. We concluded that aging associated decline in ultra–endurance performance is inevitable although it can be slowed down.

Keywords: aging, triathlon, atrophy, endurance

Procedia PDF Downloads 373
1286 Optimization Based Extreme Learning Machine for Watermarking of an Image in DWT Domain

Authors: RAM PAL SINGH, VIKASH CHAUDHARY, MONIKA VERMA

Abstract:

In this paper, we proposed the implementation of optimization based Extreme Learning Machine (ELM) for watermarking of B-channel of color image in discrete wavelet transform (DWT) domain. ELM, a regularization algorithm, works based on generalized single-hidden-layer feed-forward neural networks (SLFNs). However, hidden layer parameters, generally called feature mapping in context of ELM need not to be tuned every time. This paper shows the embedding and extraction processes of watermark with the help of ELM and results are compared with already used machine learning models for watermarking.Here, a cover image is divide into suitable numbers of non-overlapping blocks of required size and DWT is applied to each block to be transformed in low frequency sub-band domain. Basically, ELM gives a unified leaning platform with a feature mapping, that is, mapping between hidden layer and output layer of SLFNs, is tried for watermark embedding and extraction purpose in a cover image. Although ELM has widespread application right from binary classification, multiclass classification to regression and function estimation etc. Unlike SVM based algorithm which achieve suboptimal solution with high computational complexity, ELM can provide better generalization performance results with very small complexity. Efficacy of optimization method based ELM algorithm is measured by using quantitative and qualitative parameters on a watermarked image even though image is subjected to different types of geometrical and conventional attacks.

Keywords: BER, DWT, extreme leaning machine (ELM), PSNR

Procedia PDF Downloads 311
1285 Analysis of the Development of Communicative Skills After Participating in the Equine-Assisted-Therapy Program Step-By-Step in Communication

Authors: Leticia Souza Guirra, Márcia Eduarda Vieira Ramos, Edlaine Souza Pereira, Leticia Correa Celeste

Abstract:

Introduction: Studies indicate that equine-assisted therapy enables improvements in several areas of functioning that are impaired in children with autism spectrum disorder (ASD), such as social interaction and communication. Objective: The study proposes to analyze the development of dialogic skills of a verbal child with ASD after participating in the equine-assisted therapy Step By Step in Communication. Method: This is quantitative and qualitative research through a case study. It refers to a 6 years old child diagnosed with ASD belonging to a group of practitioners of the Brazilian National Equine-Assited-Therapy Association. The Behavioral Observation Protocol (PROC) was used to evaluate communicative skills before and after the intervention, which consisted of 24 sessions once a week. Results: All conversational skills increased their frequency, with participation in dialogue and initiation of interaction. The child also increases the habit of waiting for his turn and answering the interlocutor. The emission of topics not related to conversation and echolalia showed a significant decrease after the intervention. Conclusion: The studied child showed improvement in communicative skills after participating in the equine-assisted therapy Step By Step in Communication. Contributions: This study contributes to a greater understanding of the impact of equine-assisted therapy on the communicative abilities of children with ASD.

Keywords: equine-assisted-therapy, autism spectrum disorder, language, communication, language and hearing sciences

Procedia PDF Downloads 81
1284 Speech Detection Model Based on Deep Neural Networks Classifier for Speech Emotions Recognition

Authors: A. Shoiynbek, K. Kozhakhmet, P. Menezes, D. Kuanyshbay, D. Bayazitov

Abstract:

Speech emotion recognition has received increasing research interest all through current years. There was used emotional speech that was collected under controlled conditions in most research work. Actors imitating and artificially producing emotions in front of a microphone noted those records. There are four issues related to that approach, namely, (1) emotions are not natural, and it means that machines are learning to recognize fake emotions. (2) Emotions are very limited by quantity and poor in their variety of speaking. (3) There is language dependency on SER. (4) Consequently, each time when researchers want to start work with SER, they need to find a good emotional database on their language. In this paper, we propose the approach to create an automatic tool for speech emotion extraction based on facial emotion recognition and describe the sequence of actions of the proposed approach. One of the first objectives of the sequence of actions is a speech detection issue. The paper gives a detailed description of the speech detection model based on a fully connected deep neural network for Kazakh and Russian languages. Despite the high results in speech detection for Kazakh and Russian, the described process is suitable for any language. To illustrate the working capacity of the developed model, we have performed an analysis of speech detection and extraction from real tasks.

Keywords: deep neural networks, speech detection, speech emotion recognition, Mel-frequency cepstrum coefficients, collecting speech emotion corpus, collecting speech emotion dataset, Kazakh speech dataset

Procedia PDF Downloads 101
1283 Review on Crew Scheduling of Bus Transit: A Case Study in Kolkata

Authors: Sapan Tiwari, Namrata Ghosh

Abstract:

In urban mass transit, crew scheduling always plays a significant role. It deals with the formulation of work timetables for its staff so that an organization can meet the demand for its products or services. The efficient schedules of a specified timetable have an enormous impact on staff demand. It implies that an urban mass transit company's financial outcomes are strongly associated with planning operations in the region. The research aims to demonstrate the state of the crew scheduling studies and its practical implementation in mass transit businesses in metropolitan areas. First, there is a short overview of past studies in the field. Subsequently, the restrictions and problems with crew scheduling and some models, which have been developed to solve the related issues with their mathematical formulation, are defined. The comments are completed by a description of the solution opportunities provided by computer-aided scheduling program systems for operational use and exposures from urban mass transit organizations. Furthermore, Bus scheduling is performed using the Hungarian technique of problem-solving tasks and mathematical modeling. Afterward, the crew scheduling problem, which consists of developing duties using predefined tasks with set start and end times and places, is resolved. Each duty has to comply with a set line of work. The objective is to minimize a mixture of fixed expenses (number of duties) and varying costs. After the optimization of cost, the outcome of the research is that the same frequency can be provided with fewer buses and less workforce.

Keywords: crew scheduling, duty, optimization of cost, urban mass transit

Procedia PDF Downloads 150
1282 Case Study: Optimization of Contractor’s Financing through Allocation of Subcontractors

Authors: Helen S. Ghali, Engy Serag, A. Samer Ezeldin

Abstract:

In many countries, the construction industry relies heavily on outsourcing models in executing their projects and expanding their businesses to fit in the diverse market. Such extensive integration of subcontractors is becoming an influential factor in contractor’s cash flow management. Accordingly, subcontractors’ financial terms are important phenomena and pivotal components for the well-being of the contractor’s cash flow. The aim of this research is to study the contractor’s cash flow with respect to the owner and subcontractor’s payment management plans, considering variable advance payment, payment frequency, and lag and retention policies. The model is developed to provide contractors with a decision support tool that can assist in selecting the optimum subcontracting plan to minimize the contractor’s financing limits and optimize the profit values. The model is built using Microsoft Excel VBA coding, and the genetic algorithm is utilized as the optimization tool. Three objective functions are investigated, which are minimizing the highest negative overdraft value, minimizing the net present worth of overdraft, and maximizing the project net profit. The model is validated on a full-scale project which includes both self-performed and subcontracted work packages. The results show potential outputs in optimizing the contractor’s negative cash flow values and, in the meantime, assisting contractors in selecting suitable subcontractors to achieve the objective function.

Keywords: cash flow optimization, payment plan, procurement management, subcontracting plan

Procedia PDF Downloads 132
1281 Facilitation of Digital Culture and Creativity through an Ideation Strategy: A Case Study with an Incumbent Automotive Manufacturer

Authors: K. Ö. Kartal, L. Maul, M. Hägele

Abstract:

With the development of new technologies come additional opportunities for the founding of companies and new markets to be created. The barriers to entry are lowered and technology makes old business models obsolete. Incumbent companies have to be adaptable to this quickly changing environment. They have to start the process of digital maturation and they have to be able to adapt quickly to new and drastic changes that might arise. One of the biggest barriers for organizations in order to do so is their culture. This paper shows the core elements of a corporate culture that supports the process of digital maturation in incumbent organizations. Furthermore, it is explored how ideation and innovation can be used in a strategy in order to facilitate these core elements of culture that promote digital maturity. Focus areas are identified for the design of ideation strategies, with the aim to make the facilitation and incitation process more effective, short to long term. Therefore, one in-depth case study is conducted with data collection from interviews, observation, document review and surveys. The findings indicate that digital maturity is connected to cultural shift and 11 relevant elements of digital culture are identified which have to be considered. Based on these 11 core elements, five focus areas that need to be regarded in the design of a strategy that uses ideation and innovation to facilitate the cultural shift are identified. These are: Focus topics, rewards and communication, structure and frequency, regions and new online formats.

Keywords: digital transformation, innovation management, ideation strategy, creativity culture, change

Procedia PDF Downloads 196
1280 Evaluation of Modulus of Elasticity by Non-Destructive Method of Hybrid Fiber Reinforced Concrete

Authors: Erjola Reufi, Thomas Beer

Abstract:

Plain, unreinforced concrete is a brittle material, with a low tensile strength, limited ductility and little resistance to cracking. In order to improve the inherent tensile strength of concrete there is a need of multi directional and closely spaced reinforcement, which can be provided in the form of randomly distributed fibers. Fiber reinforced concrete (FRC) is a composite material consisting of cement, sand, coarse aggregate, water and fibers. In this composite material, short discrete fibers are randomly distributed throughout the concrete mass. The behavioral efficiency of this composite material is far superior to that of plain concrete and many other construction materials of equal cost. The present experimental study considers the effect of steel fibers and polypropylene fiber on the modulus of elasticity of concrete. Hook end steel fibers of length 5 cm and 3 cm at volume fraction of 0.25%, 0.5% and 1.% were used. Also polypropylene fiber of length 12, 6, 3 mm at volume fraction 0.1, 0.25, and 0.4 % were used. Fifteen mixtures has been prepared to evaluate the effect of fiber on modulus of elasticity of concrete. Ultrasonic pulse velocity (UPV) and resonant frequency methods which are two non-destructive testing techniques have been used to measure the elastic properties of fiber reinforced concrete. This study found that ultrasonic wave propagation is the most reliable, easy and cost effective testing technique to use in the determination of the elastic properties of the FRC mix used in this study.

Keywords: fiber reinforced concrete(FRC), polypropylene fiber, resonance, ultrasonic pulse velocity, steel fiber

Procedia PDF Downloads 302
1279 A Descriptive Study on Psychiatric Morbidity among Nurses Working in Selected Hospitals of Udupi and Mangalore Districts Karnataka, India

Authors: Tessy Treesa Jose, Sripathy M. Bhat

Abstract:

Nursing is recognized as a stressful occupation and has indicated a probable high prevalence of distress. It is a helping profession requiring a high degree of commitment and involvement. If stress is intense, continuous and repeated, it becomes a negative phenomenon or "distress," which can lead to physical illness and psychological disorders. The frequency of common psychosomatic symptoms including sleeping problems, tension headache, chronic fatigue, palpitation etc. may be an indicator of nurses’ work-related stress level. Objectives of the study were to determine psychiatric morbidity among nurses and to find its association with selected variables. The study population consisted of 1040 registered nurses working in selected medical college hospitals and government hospitals of Udupi and Mangalore districts. Descriptive survey design was used to conduct the study. Subjects were selected by using purposive sampling. Data were gathered by administering background proforma and General Health questionnaire. Severe distress was experienced by 0.9% of nurses and 5.6% had some evidence of distress. Subjects who did not have any distress were 93.5%. No significant association between psychiatric morbidity in nurses and demographic variables was observed. With regard to work variables significant association is observed between psychiatric morbidity and total years of experience (z=10.67, p=0.03) and experience in current area of work (z=9.43, p=0.02).

Keywords: psychiatric morbidity, nurse, selected hospitals, working

Procedia PDF Downloads 291
1278 2-Dimensional Kinematic Analysis on Sprint Start with Sprinting Performance of Novice Athletes

Authors: Satpal Yadav, Biswajit Basumatary, Arvind S. Sajwan, Ranjan Chakravarty

Abstract:

The purpose of the study was to assess the effect of 2D kinematical selected variables on sprint start with sprinting performance of novice athletes. Six (3 National and 3 State level) athletes of sports authority of India, Guwahati has been selected for this study. The mean (M) and standard deviation (SD) of sprinters were age (17.44, 1.55), height (1.74m, .84m), weight (62.25 kg, 4.55), arm length (65.00 cm, 3.72) and leg length (96.35 cm, 2.71). Biokin-2D motion analysis system V4.5 can be used for acquiring two-dimensional kinematical data/variables on sprint start with Sprinting Performance. For the purpose of kinematic analysis a standard motion driven camera which frequency of the camera was 60 frame/ second i.e. handy camera of Sony Company were used. The sequence of photographic was taken under controlled condition. The distance of the camera from the athletes was 12 mts away and was fixed at 1.2-meter height. The result was found that National and State level athletes significant difference in there, trajectory knee, trajectory ankle, displacement knee, displacement ankle, linear velocity knee, linear velocity ankle, and linear acceleration ankle whereas insignificant difference was found between National and State level athletes in their linear acceleration knee joint on sprint start with sprinting performance. For all the Statistical test the level of significance was set at p<0.05.

Keywords: 2D kinematic analysis, sprinting performance, novice athletes, sprint start

Procedia PDF Downloads 323
1277 Enhanced Flight Dynamics Model to Simulate the Aircraft Response to Gust Encounters

Authors: Castells Pau, Poetsch Christophe

Abstract:

The effect of gust and turbulence encounters on aircraft is a wide field of study which allows different approaches, from high-fidelity multidisciplinary simulations to more simplified models adapted to industrial applications. The typical main goal is to predict the gust loads on the aircraft in order to ensure a safe design and achieve certification. Another topic widely studied is the gust loads reduction through an active control law. The impact of gusts on aircraft handling qualities is of interest as well in the analysis of in-service events so as to evaluate the aircraft response and the performance of the flight control laws. Traditionally, gust loads and handling qualities are addressed separately with different models adapted to the specific needs of each discipline. In this paper, an assessment of the differences between both models is presented and a strategy to better account for the physics of gust encounters in a typical flight dynamics model is proposed based on the model used for gust loads analysis. The applied corrections aim to capture the gust unsteady aerodynamics and propagation as well as the effect of dynamic flexibility at low frequencies. Results from the gust loads model at different flight conditions and measures from real events are used for validation. An assessment of a possible extension of steady aerodynamic nonlinearities to low frequency range is also addressed. The proposed corrections provide meaningful means to evaluate the performance and possible adjustments of the flight control laws.

Keywords: flight dynamics, gust loads, handling qualities, unsteady aerodynamics

Procedia PDF Downloads 147
1276 Mitigation of Interference in Satellite Communications Systems via a Cross-Layer Coding Technique

Authors: Mario A. Blanco, Nicholas Burkhardt

Abstract:

An important problem in satellite communication systems which operate in the Ka and EHF frequency bands consists of the overall degradation in link performance of mobile terminals due to various types of degradations in the link/channel, such as fading, blockage of the link to the satellite (especially in urban environments), intentional as well as other types of interference, etc. In this paper, we focus primarily on the interference problem, and we develop a very efficient and cost-effective solution based on the use of fountain codes. We first introduce a satellite communications (SATCOM) terminal uplink interference channel model that is classically used against communication systems that use spread-spectrum waveforms. We then consider the use of fountain codes, with focus on Raptor codes, as our main mitigation technique to combat the degradation in link/receiver performance due to the interference signal. The performance of the receiver is obtained in terms of average probability of bit and message error rate as a function of bit energy-to-noise density ratio, Eb/N0, and other parameters of interest, via a combination of analysis and computer simulations, and we show that the use of fountain codes is extremely effective in overcoming the effects of intentional interference on the performance of the receiver and associated communication links. We then show this technique can be extended to mitigate other types of SATCOM channel degradations, such as those caused by channel fading, shadowing, and hard-blockage of the uplink signal.

Keywords: SATCOM, interference mitigation, fountain codes, turbo codes, cross-layer

Procedia PDF Downloads 361
1275 Ab Initio Calculations of Structure and Elastic Properties of BexZn1−xO Alloys

Authors: S. Lakel, F. Elhamra, M. Ibrir, K. Almi

Abstract:

There is a growing interest in Zn1-xBexO (ZBO)/ZnO hetero structures and quantum wells since the band gap energy of Zn1-xBexO solid solutions can be turned over a very large range (3.37–10.6 eV) as a function of the Be composition. ZBO/ZnO has been utilized in ultraviolet light emission diodes and lasers, and may find applications as active elements of various other electronic and optoelectronic devices. Band gap engineering by Be substitution enables the facile preparation of barrier layers and quantum wells in device structures. In addition, ZnO and its ternary alloys, as piezoelectric semiconductors, have been used for high-frequency surface acoustic wave devices in wireless communication systems due to their high acoustic velocities and large electromechanical coupling. However, many important parameters such as elastic constants, bulk modulus, Young’s modulus and band-gap bowing. First-principles calculations of the structural, electrical and elastic properties of Zn1-xBexO as a function of the Be concentration x have been performed within density functional theory using norm-conserving pseudopotentials and local density approximation (LDA) for the exchange and correlation energy. The alloys’ lattice constants may deviate from the Vegard law. As Be concentration increases, the elastic constants, the bulk modulus and Young’s modulus of the alloys increase, the band gap increases with increasing Be concentration and Zn1-xBexO alloys have direct band. Our calculated results are in good agreement with experimental data and other theoretical calculations.

Keywords: DFT calculation, norm-conserving pseudopotentials, ZnBeO alloys, ZnO

Procedia PDF Downloads 519
1274 The Analysis of Internet and Social Media Behaviors of the Students in Vocational High School

Authors: Mehmet Balci, Sakir Tasdemir, Mustafa Altin, Ozlem Bozok

Abstract:

Our globalizing world has become almost a small village and everyone can access any information at any time. Everyone lets each other know who does whatever in which place. We can learn which social events occur in which place in the world. From the perspective of education, the course notes that a lecturer use in lessons in a university in any state of America can be examined by a student studying in a city of Africa or the Far East. This dizzying communication we have mentioned happened thanks to fast developments in computer technologies and in parallel with this, internet technology. While these developments in the world, has a very large young population and a rapidly evolving electronic communications infrastructure Turkey has been affected by this situation. Researches has shown that almost all young people in Turkey has an account in a social network. Especially becoming common of mobile devices causes data traffic in social networks to increase. In this study, has been surveyed on students in the different age groups and at the Selcuk University Vocational School of Technical Sciences Department of Computer Technology. Student’s opinions about the use of internet and social media has been gotten. Using the Internet and social media skills, purposes, operating frequency, access facilities and tools, social life and effects on vocational education etc. have been explored. Both internet and use of social media positive and negative effects on this department students results have been obtained by the obtained findings evaluating from various aspects. Relations and differences have been found out with statistic.

Keywords: computer technologies, internet use, social network, higher vocational school

Procedia PDF Downloads 542
1273 Study of Aqueous Solutions: A Dielectric Spectroscopy Approach

Authors: Kumbharkhane Ashok

Abstract:

The time domain dielectric relaxation spectroscopy (TDRS) probes the interaction of a macroscopic sample with a time-dependent electrical field. The resulting complex permittivity spectrum, characterizes amplitude (voltage) and time scale of the charge-density fluctuations within the sample. These fluctuations may arise from the reorientation of the permanent dipole moments of individual molecules or from the rotation of dipolar moieties in flexible molecules, like polymers. The time scale of these fluctuations depends on the sample and its relative relaxation mechanism. Relaxation times range from some picoseconds in low viscosity liquids to hours in glasses, Therefore the DRS technique covers an extensive dynamical process, its corresponding frequency range from 10-4 Hz to 1012 Hz. This inherent ability to monitor the cooperative motion of molecular ensemble distinguishes dielectric relaxation from methods like NMR or Raman spectroscopy which yield information on the motions of individual molecules. An experimental set up for Time Domain Reflectometry (TDR) technique from 10 MHz to 30 GHz has been developed for the aqueous solutions. This technique has been very simple and covers a wide band of frequencies in the single measurement. Dielectric Relaxation Spectroscopy is especially sensitive to intermolecular interactions. The complex permittivity spectra of aqueous solutions have been fitted using Cole-Davidson (CD) model to determine static dielectric constants and relaxation times for entire concentrations. The heterogeneous molecular interactions in aqueous solutions have been discussed through Kirkwood correlation factor and excess properties.

Keywords: liquid, aqueous solutions, time domain reflectometry

Procedia PDF Downloads 444
1272 2D Numerical Modeling of Ultrasonic Measurements in Concrete: Wave Propagation in a Multiple-Scattering Medium

Authors: T. Yu, L. Audibert, J. F. Chaix, D. Komatitsch, V. Garnier, J. M. Henault

Abstract:

Linear Ultrasonic Techniques play a major role in Non-Destructive Evaluation (NDE) for civil engineering structures in concrete since they can meet operational requirements. Interpretation of ultrasonic measurements could be improved by a better understanding of ultrasonic wave propagation in a multiple scattering medium. This work aims to develop a 2D numerical model of ultrasonic wave propagation in a heterogeneous medium, like concrete, integrating the multiple scattering phenomena in SPECFEM software. The coherent field of multiple scattering is obtained by averaging numerical wave fields, and it is used to determine the effective phase velocity and attenuation corresponding to an equivalent homogeneous medium. First, this model is applied to one scattering element (a cylinder) in a homogenous medium in a linear-elastic system, and its validation is completed thanks to the comparison with analytical solution. Then, some cases of multiple scattering by a set of randomly located cylinders or polygons are simulated to perform parametric studies on the influence of frequency and scatterer size, concentration, and shape. Also, the effective properties are compared with the predictions of Waterman-Truell model to verify its validity. Finally, the mortar viscoelastic behavior is introduced in the simulation in order to considerer the dispersion and the attenuation due to porosity included in the cement paste. In the future, different steps will be developed: The comparisons with experimental results, the interpretation of NDE measurements, and the optimization of NDE parameters before an auscultation.

Keywords: attenuation, multiple-scattering medium, numerical modeling, phase velocity, ultrasonic measurements

Procedia PDF Downloads 275
1271 A Retrospective Study of Dog Bite Occurrence and Anti Rabies Vaccination of Dogs in Veterinary Clinics in Aba, Abia State Nigeria from January 2016 to December 2020

Authors: Innocent C. Abazie, Odukoya A. Olatunde, Ochuko Orakpoghenor, Bamidele J. Kolawole, Hannah L. Kolawole

Abstract:

This study was carried out to obtain five-year retrospective data on dog bite cases and antirabies vaccination of dogs in relation to rabies control in Aba, Abia state, Nigeria. Data for retrospective studies (2016 - 2020) was collected from both government and private veterinary clinics in Aba. A total of 66 dog bite cases were reported between January 2016 and December 2020 with a majority of victims being adults (51.5%) within the ages of 18 – 50 years. On the prevalence of dog bite cases according to the gender of victims, males (75.8%) were mostly involved compared to female victims (24.2%). Anatomically, the majority of bite wounds (65.2%) were on the legs. The monthly distribution of bites indicates a higher frequency in the months of January and March (dry season). Local 28 (43.8%) and exotic breeds 30(46.8%) of dogs were mostly involved in the dog bite cases. The majority of the dogs (92.2%) involved in the bite cases were known dogs whose owners could be contacted, while a very few proportion (7.8%) were stray dogs. Results of this study indicated that only 16 (25%) of the offending dogs had a current antirabies vaccination record, 8 (12.5%) had an unknown vaccination record, while the largest proportion, 40 (62.5%) of the offending dogs had no current vaccination record. Public awareness of the danger of dog bites in relation to rabies and increased antirabies vaccination of dogs as a means of controlling the disease is recommended.

Keywords: Aba, dog bite, rabies, vaccination profile

Procedia PDF Downloads 81
1270 Business and Psychological Principles Integrated into Automated Capital Investment Systems through Mathematical Algorithms

Authors: Cristian Pauna

Abstract:

With few steps away from the 2020, investments in financial markets is a common activity nowadays. In the electronic trading environment, the automated investment software has become a major part in the business intelligence system of any modern financial company. The investment decisions are assisted and/or made automatically by computers using mathematical algorithms today. The complexity of these algorithms requires computer assistance in the investment process. This paper will present several investment strategies that can be automated with algorithmic trading for Deutscher Aktienindex DAX30. It was found that, based on several price action mathematical models used for high-frequency trading some investment strategies can be optimized and improved for automated investments with good results. This paper will present the way to automate these investment decisions. Automated signals will be built using all of these strategies. Three major types of investment strategies were found in this study. The types are separated by the target length and by the exit strategy used. The exit decisions will be also automated and the paper will present the specificity for each investment type. A comparative study will be also included in this paper in order to reveal the differences between strategies. Based on these results, the profit and the capital exposure will be compared and analyzed in order to qualify the investment methodologies presented and to compare them with any other investment system. As conclusion, some major investment strategies will be revealed and compared in order to be considered for inclusion in any automated investment system.

Keywords: Algorithmic trading, automated investment systems, limit conditions, trading principles, trading strategies

Procedia PDF Downloads 194
1269 Quranic Recitation Listening Relate to Memory Processing, Language Selectivity and Attentional Process

Authors: Samhani Ismail, Tahamina Begum, Faruque Reza, Zamzuri Idris, Hafizan Juahir, Jafri Malin Abdullah

Abstract:

Holy Quran, a rhymed prosed scripture has a complete literary structure that exemplifies the peak of literary beauty. Memorizing of its verses could enhance one’s memory capacity and cognition while those who are listening to its recitation it is also believed that the Holy Quran alter brainwave producing neuronal excitation engaging with cognitive processes. 28 normal healthy subjects (male =14 & female = 14) were recruited and EEG recording was done using 128-electrode sensor net (Electrical Geosics, Inc.) with the impedance of ≤ 50kΩ. They listened to Sura Fatiha recited by Sheikh Qari Abdul Basit bin Abdus Samad. Arabic news and no sound were chosen as positive and negative control, respectively. The waveform was analysed by Fast Fourier Transform (FFT) to get the power in frequency bands. Bilateral frontal (F7, F8) and temporal region (T7, T8) showed decreased power significantly in alpha wave band in respondent stimulated by Sura Fatihah recitation reflects acoustic attention processing. However, decreased in alpha power in selective attention to memorized, and in familial but not memorized language, reveals the memorial processing in long-term memory. As a conclusion, Quranic recitation relates both cognitive element of memory and language in its listeners and memorizers.

Keywords: auditory stimulation, cognition, EEG, linguistic, memory, Quranic recitation

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1268 Islamophobia, Years After 9/11: An Assessment of the American Media

Authors: Nasa'i Muhammad Gwadabe

Abstract:

This study seeks to find the extent to which the old Islamophobic prejudice was tilted towards a more negative direction in the United States following the 9/11 terrorist attacks. It is hypothesized that, the 9/11 attacks in the United States reshaped the old Islamophobic prejudice through the reinforcement of a strong social identity construction of Muslims as “out-group”. The “social identity” and “discourse representation” theories are used as framework for analysis. To test the hypothesis, two categories were created: the prejudice (out-group) and the tolerance (in-group) categories. The Prejudice (out-group) against Muslims category was coded to include six attributes: (Terrorist, Threat, Women's Rights violation, Undemocratic, Backward and Intolerant); while the tolerance (In-group) for Muslims category was also coded to include six attributes: (Peaceful, civilized, educated, partners trustworthy and honest). Data are generated from the archives of three American newspapers: The Los Angeles Times, New York Times and USA Today using specific search terms and specific date range; from 9/11/1996 to 9/11/2006, that is five years before and five years after the 9/11. An aggregate of 20595 articles were generated from the search of the three newspapers throughout the search periods. Conclusively, for both pre and post 9/11 periods, the articles generated under the category of prejudice (out-group) against Muslims revealed a higher frequency, against that of tolerance (in-group) for them, which is lesser. Finally, The comparison between the pre and post 9/11 periods showed that, the increased Prejudice (out-group) against Muslims was most influenced through libeling them as terrorist, which signaled a skyrocketed increase from pre to post 9/11.

Keywords: in-group, Islam, Islamophobia, Muslims, out-group, prejudice, terrorism, the 9/11 and tolerance

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1267 Loving and Letting Go: Bounded Attachment in Creative Work

Authors: Greg Fetzer

Abstract:

One of the fundamental tensions of creative work is between the need to be passionate and persistent in advancing novel and risky ideas and the need to be flexible, revising, or even abandoning ideas in favor of others. The tension becomes fraught in part because of the attachment that creators have toward their ideas. Idea attachment is defined here as a multifaceted concept referring to affection, passion, and connection toward a target—in this case, one’s projects or ideas. Yet feeling attached can make creators resistant to feedback, making them less flexible and leading them to escalate commitment. Despite a growing understanding of how attachment develops and evolves in response to project changes, feedback, and creative jolts, we still know relatively little about the organizational dynamics that may shape idea attachment. Through a qualitative, inductive study of early-stage R&D scientists in the pharmaceutical industry, this research finds that scientists develop bounded attachment, a mindset that limits emotional attachment to ideas while still fostering engagement in idea development. This research develops a process model of how bounded attachment is developed and enacted across three stages of the creative process, idea generation, idea evaluation, and outcome assessment, as well as the role that organizational practices and professional identity play in shaping this process: these collective practices provided structures to ensure ideas were evaluated in a rational (i.e. non-emotional way) while also providing socioemotional support in the face of setbacks. Together, this process led to continued creative engagement across ideas in a portfolio and helped scientists construct a sense of meaningful work despite a high likelihood (and frequency) of failure.

Keywords: creativity, innovation, organizational practices, qualitative, attachment

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1266 Barriers and Opportunities for Implementing Electronic Prescription Software in Public Libyan Hospitals

Authors: Abdelbaset M. Elghriani, Abdelsalam M. Maatuk, Isam Denna, Amira Abdulla Werfalli

Abstract:

Electronic prescription software (e-prescribing) benefits patients and physicians by preventing handwriting errors and giving accurate prescriptions. E-prescribing allows prescriptions to be written and sent to pharmacies electronically instead of using handwritten notes. Significant factors that may affect the adoption of e-prescription systems include lacking technical support, financial resources to operate the systems, and change resistance from some clinicians, which have been identified as barriers to the implementation of e-prescription systems. This study aims to explore the trends and opinions of physicians and pharmacists about e-prescriptions and to identify the obstacles and benefits of the application of e-prescriptions in the health care system. A cross-sectional descriptive study was conducted at three Libyan public hospitals. Data were collected through a self-constructed questionnaire to assess the opinions regarding potential constraining factors and benefits of implementing an e-prescribing system in hospitals. Data presented as mean, frequency distribution table, cross-tabulation, and bar charts. Data analysis was performed, and the results show that technical, financial, and organizational obstacles are the most important obstacles that prevent the application of e-prescribing systems in Libyan hospitals. In addition, there was awareness of the benefits of e-prescribing, especially reducing medication dispensing errors, and a desire of physicians and pharmacists to use electronic prescriptions.

Keywords: physicians, e-prescribing, health care system, pharmacists

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1265 Investigating Dynamic Transition Process of Issues Using Unstructured Text Analysis

Authors: Myungsu Lim, William Xiu Shun Wong, Yoonjin Hyun, Chen Liu, Seongi Choi, Dasom Kim, Namgyu Kim

Abstract:

The amount of real-time data generated through various mass media has been increasing rapidly. In this study, we had performed topic analysis by using the unstructured text data that is distributed through news article. As one of the most prevalent applications of topic analysis, the issue tracking technique investigates the changes of the social issues that identified through topic analysis. Currently, traditional issue tracking is conducted by identifying the main topics of documents that cover an entire period at the same time and analyzing the occurrence of each topic by the period of occurrence. However, this traditional issue tracking approach has limitation that it cannot discover dynamic mutation process of complex social issues. The purpose of this study is to overcome the limitations of the existing issue tracking method. We first derived core issues of each period, and then discover the dynamic mutation process of various issues. In this study, we further analyze the mutation process from the perspective of the issues categories, in order to figure out the pattern of issue flow, including the frequency and reliability of the pattern. In other words, this study allows us to understand the components of the complex issues by tracking the dynamic history of issues. This methodology can facilitate a clearer understanding of complex social phenomena by providing mutation history and related category information of the phenomena.

Keywords: Data Mining, Issue Tracking, Text Mining, topic Analysis, topic Detection, Trend Detection

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1264 Initiative Strategies on How to Increase Value Add of the Recycling Business

Authors: Yananda Siraphatthada

Abstract:

The current study was the succession of a previous study on value added of recycling business management. Its aims are to 1) explore conditions on how to increasing value add of Thai recycling business, and 2) exam the implementation of the 3-staged plan (short, medium, and long term), suggested by the former study, to increase value added of the recycling business as immediate mechanisms to accelerate government operation. Quantitative and qualitative methods were utilized in this research. A qualitative research consisted of in-depth interviews and focus group discussions. Responses were obtained from owners of the waste separation plants, and recycle shops, as well as officers in relevant governmental agencies. They were randomly selected via Quota Sampling. Data was analyzed via content analysis. The sample used for quantitative method consisted of 1,274 licensed recycling operators in eight provinces. The operators were randomly stratified via sampling method. Data were analyzed via descriptive statistics frequency, percentage, average (mean), and standard deviation. The study recommended three-staged plan: short, medium, and long terms. The plan included the development of logistics, the provision of quality market/plants, the amendment of recycling rules/regulation, the restructuring recycling business, the establishment of green-purchasing recycling center, support for the campaigns run by the International Green Purchasing Network (IGPN), conferences/workshops as a public forum to share insights among experts/concern people.

Keywords: strategies, value added, recycle, business

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1263 Surface Modified Thermoplastic Polyurethane and Poly(Vinylidene Fluoride) Nanofiber Based Flexible Triboelectric Nanogenerator and Wearable Bio-Sensor

Authors: Sk Shamim Hasan Abir, Karen Lozano, Mohammed Jasim Uddin

Abstract:

Over the last few years, nanofiber-based triboelectric nanogenerator (TENG) has caught great attention among researchers all over the world due to its inherent capability of converting mechanical energy to usable electrical energy. In this study, poly(vinylidene fluoride) (PVDF) and thermoplastic polyurethane (TPU) nanofiber prepared by Forcespinning® (FS) technique were used to fabricate TENG for self-charging energy storage device and biomechanical body motion sensor. The surface of the TPU nanofiber was modified by uniform deposition of thin gold film to enhance the frictional properties; yielded 254 V open-circuit voltage (Voc) and 86 µA short circuit current (Isc), which were 2.12 and 1.87 times greater in contrast to bare PVDF-TPU TENG. Moreover, the as-fabricated PVDF-TPU/Au TENG was tested against variable capacitors and resistive load, and the results showed that with a 3.2 x 2.5 cm2 active contact area, it can quick charge up to 7.64 V within 30 seconds using a 1.0 µF capacitor and generate significant 2.54 mW power, enough to light 75 commercial LEDs (1.5 V each) by the hand tapping motion at 4 Hz (240 beats per minutes (bpm)) load frequency. Furthermore, the TENG was attached to different body parts to capture distinctive electrical signals for various body movements, elucidated the prospective usability of our prepared nanofiber-based TENG in wearable body motion sensor application.

Keywords: biomotion sensor, forcespinning, nanofibers, triboelectric nanogenerator

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1262 Prevention of COVID-19 Using Herbs and Natural Products

Authors: Nada Alqadri, Omaima Nasir

Abstract:

Natural compounds are an important source of potential inhibitors; they have a lot of pharma potential with less adverse effects. The effective antiviral activities of natural products have been proved in different studies. The outbreak of COVID-19 in Wuhan, Hubei, in December 2019, coronavirus has had a significant impact on people's health and lives. Based on previous studies, natural products can be introduced as preventive and therapeutic agents in the fight against COVID-19; considering that no food or supplement has been authorized to prevent COVID-19, individuals continue to search for and consume specific herbs, foods, and commercial supplements for this purpose. This study will be aimed to estimate the uses of herbal and natural products during the COVID-19 infection to determine their usage reasons and evaluate their potential side effects. An online cross-sectional survey of different participants will be conducted and will be a focus on respondents’ chronic disease histories, socio-dmographic characteristics, and frequency and trends of using these products. Descriptive and univariate analyses will be performed to determine prevalence and associations between various products used and respondents’ socio-demographic data. Relationships will be tested using Pearson’s chi-square test or an exact probability test. Our main findings will give evidence of beneficial uses of natural products and herbal medicine as prophylactic and will be a vigorous approach to stop or at least slow down COVID-19 infection and transmission. This will be of great interest of public health, and the results of our study will lend health officials better control on the current pandemic.

Keywords: COVID-19, herbs, natural products, saudi arabia

Procedia PDF Downloads 218
1261 Radioprotective Effects of Selenium and Vitamin-E against 6Mv X-Rays in Human Volunteers Blood Lymphocytes by Micronuclei Assay

Authors: Vahid Changizi, Aram Rostami, Akbar Mosavi

Abstract:

Purpose of study: Critical macromolecules of cells such as DNA are in exposure to damage of free radicals that induced from interaction of ionizing radiation with biological systems. Selenium and vitamin-E are natural compound that has been shown to be a direct free radical scavenger. The aim of this study was to investigate the in vivo/in vitro radioprotective effect of selenium and vitamin-E separately and synergistically against genotoxicity induced by 6MV x-rays irradiation in cultured blood lymphocytes from 15 human volunteers. Methods: Fifteen volunteers were divided in three groups include A, B and C. These groups were given slenium(800 IU), vitamin-E(100 mg) and selenium(400 IU) + vitamin-E(50 mg), respectively. Peripheral blood samples were collected from each group before(0 hr) and 1, 2 and 3 hr after selenium and vitamin-E administration (separately and synergistically). Then the blood samples were irradiated to 200 cGy of 6 Mv x-rays. After that, lymphocyte samples were cultured with mitogenic stimulation to determine the chromosomal aberrations wih micronucleus assay in cytokinesis-blocked binucleated cells. Results: The lymphocytes in the blood samples collected at 1 hr after ingestion selenium and vitamin-E, exposed in vitro to x-rays exhibited a significant decrease in the incidence of micronuclei, compared with control group at 0 hr. The maximum protection and decrease in frequency of micronuclei(50%) was observed at 1 hr after administration of selenium and vitamin-E synergistically. Conclusion: The data suggest that ingestion of selenium and vitamin-E as a radioprotector substances before exposures may reduce genetic damage caused by x-rays irradiation.

Keywords: x-rays, selenium, vitamin-e, lymphocyte, micronuclei

Procedia PDF Downloads 267