Search results for: variable elastic foundation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4159

Search results for: variable elastic foundation

2449 Identification of Paleogeomorphology at Kedulan Temple, Sleman, Yogyakarta

Authors: Virgina Claudia Latengke, Muhaammad Nur Arifin, Vanny Septia Sundari

Abstract:

Kedulan Temple is located in Dusun Kedulan, Sleman, Yogyakarta, Indonesia at coordinates S 07o 44’ 57’, E 110o 28’ 17’. Kedulan Temple is a trace of the relics of life in the 3 century AD. The Kedulan Temple including exhumed landforms, which the primordial landform is first surface topography, then buried under cover mass and exposed or re-inscribed. Recognized by the existence of ancient soil (paleosoil) and ancient objects. Seen from the type of soil that closes the temple, there are 13 layers of lava type, so it is estimated that the lava that buried the temple came from 13 times the eruption of Mount Merapi. The material that buries the base of this temple is the pyroclastic surge deposits in 3 layers, each of which is limited by a thin layer of paleosol, the sediments are 1445+/-50 yBP, 1175+/-50 yBP, and 1060+/-40 yBP. This temple is buried and dug again at 940+/-100 yBP. Furthermore, the temple affected by earthquake, so the floor and foundation becomes bumpy and most of the temple stone are thrown. The temple is left alone, until exposed to hot clouds at 1285 M (740+/-50yBP). Next, repeatedly buried lava in 4 periods, in 1587 M (360+/-50 yBP, 240+/-50 yBP, 200+/-50 yBP and unknown date). From studying this temple, can be known paleogeomorphology process that occurred in Yogyakarta, especially related to the volcanic activity of Mount Merapi. Until now, the water is still flowing around the temple so there is a fluvial process that began to take a role in the temple.

Keywords: Kedulan temple, paleogeomorphology, buried, mount Merapi, Yogyakarta

Procedia PDF Downloads 165
2448 The Governance of Islamic Banks in Morocco: Meaning, Strategic Vision and Purposes Attributed to the Governance System

Authors: Lalla Nezha Lakmiti, Abdelkahar Zahid

Abstract:

Due to the setbacks on the international scene and the wave of cacophonic financial scandals affecting large international groups, the new Islamic finance industry is not immune despite its initial resistance. The purpose of this paper is to understand and analyze the meaning of the Corporate Governance (CG) concept in Moroccan Islamic banking systems with specific reference to their institutions. The research objective is to identify also the path taken and adopted by these banks recently set up in Morocco. The foundation is rooted in shari'a, in particular, no stakeholder (the shareholding approach) must be harmed, and the ethical value is reflected into these parties’ behavior. We chose a qualitative method, semi-structured interviews where six managers provided answers about their banking systems. Since these respondents held a senior position (directors) within their organizations, it is felt that they are well placed and have the necessary knowledge to provide us with information to answer the questions asked. The results identified the orientation of participating banks and assessing how governance works, while determining which party is fovoured: shareholders, stakeholders or both. This study discusses the favorable condition to the harmonization of the regulations and therefore a better integration between Islamic finance and conventional ones in the economic context of Morocco.

Keywords: corporate governance, Islamic Banks, stakeholders, shareholders

Procedia PDF Downloads 101
2447 The X-Ray Response Team: Building a National Health Pre-Hospital Service

Authors: Julian Donovan, Jessica Brealey, Matthew Bowker, Marianne Feghali, Gregory Smith, Lee Thompson, Deborah Henderson

Abstract:

This article details the development of the X-ray response team (XRT), a service that utilises innovative technology to safely deliver acute and elective imaging and medical assessment service in the pre-hospital and community setting. This involves a partnership between Northumbria Healthcare NHS Foundation Trust’s Radiology and Emergency Medicine departments and the North East Ambulance Service to create a multidisciplinary prehospital team. The team committed to the delivery of a two-day acute service every week, alongside elective referrals, starting in November 2020. The service was originally made available to a 15-mile radius surrounding the Northumbria Hospital. Due to demand, this was expanded to include the North Tyneside and Northumberland regions. The target population was specified as frail and vulnerable patients, as well as those deemed to benefit from staying in their own environment. Within the first two months, thirty-six percent of patients assessed were able to stay at home due to the provision of off-site imaging. In the future, this service aims to allow patient transfer directly to an appropriate ward or clinic, bypassing the emergency department to improve the patient journey and reduce emergency care pressures.

Keywords: frailty, imaging, pre-hospital, X-ray

Procedia PDF Downloads 188
2446 Analysis of the Significance of Multimedia Channels Using Sparse PCA and Regularized SVD

Authors: Kourosh Modarresi

Abstract:

The abundance of media channels and devices has given users a variety of options to extract, discover, and explore information in the digital world. Since, often, there is a long and complicated path that a typical user may venture before taking any (significant) action (such as purchasing goods and services), it is critical to know how each node (media channel) in the path of user has contributed to the final action. In this work, the significance of each media channel is computed using statistical analysis and machine learning techniques. More specifically, “Regularized Singular Value Decomposition”, and “Sparse Principal Component” has been used to compute the significance of each channel toward the final action. The results of this work are a considerable improvement compared to the present approaches.

Keywords: multimedia attribution, sparse principal component, regularization, singular value decomposition, feature significance, machine learning, linear systems, variable shrinkage

Procedia PDF Downloads 304
2445 Factors Influencing the Continuance Usage of Online Mobile Payment Apps: A Case Study of WECHAT Users in China

Authors: Isaac Kofi Mensah, Jianing Mi, Feng Cheng

Abstract:

This research paper seeks to investigate the factors determining the continuance usage of online mobile payment applications among WECHAT users in China. Technology Acceptance Model (TAM) and the Diffusion of Innovation (DOI) theory would both be applied as the theoretical foundation for this study. A developed instrument would be administered to the targeted sample of 1000 WECHAT Users in the City of Harbin, China, through an online questionnaire administration platform. Factors such as perceived usefulness, perceived ease of use, perceived service quality, social influence, trust in the internet, internet self-efficacy, relative advantage, compatibility, and complexity would be explored to determine its significant impact on the continuance intention to use mobile payment apps. This study is at the development and implementation stage. The successful completion of this research article would not only provide an insightful understanding of the factors influencing the decision of WECHAT users in China to use mobile payment applications but also enrich the e-commerce adoption literature.

Keywords: diffusion of innovation (DOI), e-commerce, mobile payment, technology acceptance model (TAM), WECHAT

Procedia PDF Downloads 176
2444 Analysis of School Burnout and Academic Motivation through Structural Equation Modeling

Authors: Ismail Seçer

Abstract:

The purpose of this study is to analyze the relationship between school burnout and academic motivation in high school students. The working group of the study consists of 455 students from the high schools in Erzurum city center, selected with appropriate sampling method. School Burnout Scale and Academic Motivation Scale were used in the study to collect data. Correlation analysis and structural equation modeling were used in the analysis of the data collected through the study. As a result of the study, it was determined that there are significant and negative relations between school burnout and academic motivation, and the school burnout has direct and indirect significant effects on the getting over himself, using knowledge and exploration dimension through the latent variable of academic motivation. Lastly, it was determined that school burnout is a significant predictor of academic motivation.

Keywords: school burnout, motivation, structural equation modeling, university

Procedia PDF Downloads 308
2443 Approximation of Analytic Functions of Several Variables by Linear K-Positive Operators in the Closed Domain

Authors: Tulin Coskun

Abstract:

We investigate the approximation of analytic functions of several variables in polydisc by the sequences of linear k-positive operators in Gadjiev sence. The approximation of analytic functions of complex variable by linear k-positive operators was tackled, and k-positive operators and formulated theorems of Korovkin's type for these operators in the space of analytic functions on the unit disc were introduced in the past. Recently, very general results on convergence of the sequences of linear k-positive operators on a simply connected bounded domain within the space of analytic functions were proved. In this presentation, we extend some of these results to the approximation of analytic functions of several complex variables by sequences of linear k-positive operators.

Keywords: analytic functions, approximation of analytic functions, Linear k-positive operators, Korovkin type theorems

Procedia PDF Downloads 330
2442 Impact of Chess Intervention on Cognitive Functioning of Children

Authors: Ebenezer Joseph

Abstract:

Chess is a useful tool to enhance general and specific cognitive functioning in children. The present study aims to assess the impact of chess on cognitive in children and to measure the differential impact of socio-demographic factors like age and gender of the child on the effectiveness of the chess intervention.This research study used an experimental design to study the impact of the Training in Chess on the intelligence of children. The Pre-test Post-test Control Group Design was utilized. The research design involved two groups of children: an experimental group and a control group. The experimental group consisted of children who participated in the one-year Chess Training Intervention, while the control group participated in extra-curricular activities in school. The main independent variable was training in chess. Other independent variables were gender and age of the child. The dependent variable was the cognitive functioning of the child (as measured by IQ, working memory index, processing speed index, perceptual reasoning index, verbal comprehension index, numerical reasoning, verbal reasoning, non-verbal reasoning, social intelligence, language, conceptual thinking, memory, visual motor and creativity). The sample consisted of 200 children studying in Government and Private schools. Random sampling was utilized. The sample included both boys and girls falling in the age range 6 to 16 years. The experimental group consisted of 100 children (50 from Government schools and 50 from Private schools) with an equal representation of boys and girls. The control group similarly consisted of 100 children. The dependent variables were assessed using Binet-Kamat Test of Intelligence, Wechsler Intelligence Scale for Children - IV (India) and Wallach Kogan Creativity Test. The training methodology comprised Winning Moves Chess Learning Program - Episodes 1–22, lectures with the demonstration board, on-the-board playing and training, chess exercise through workbooks (Chess school 1A, Chess school 2, and tactics) and working with chess software. Further students games were mapped using chess software and the brain patterns of the child were understood. They were taught the ideas behind chess openings and exposure to classical games were also given. The children participated in mock as well as regular tournaments. Preliminary analysis carried out using independent t tests with 50 children indicates that chess training has led to significant increases in the intelligent quotient. Children in the experimental group have shown significant increases in composite scores like working memory and perceptual reasoning. Chess training has significantly enhanced the total creativity scores, line drawing and pattern meaning subscale scores. Systematically learning chess as part of school activities appears to have a broad spectrum of positive outcomes.

Keywords: chess, intelligence, creativity, children

Procedia PDF Downloads 245
2441 Estimation of Coefficients of Ridge and Principal Components Regressions with Multicollinear Data

Authors: Rajeshwar Singh

Abstract:

The presence of multicollinearity is common in handling with several explanatory variables simultaneously due to exhibiting a linear relationship among them. A great problem arises in understanding the impact of explanatory variables on the dependent variable. Thus, the method of least squares estimation gives inexact estimates. In this case, it is advised to detect its presence first before proceeding further. Using the ridge regression degree of its occurrence is reduced but principal components regression gives good estimates in this situation. This paper discusses well-known techniques of the ridge and principal components regressions and applies to get the estimates of coefficients by both techniques. In addition to it, this paper also discusses the conflicting claim on the discovery of the method of ridge regression based on available documents.

Keywords: conflicting claim on credit of discovery of ridge regression, multicollinearity, principal components and ridge regressions, variance inflation factor

Procedia PDF Downloads 402
2440 Apatite-Forming Ability of Doped-Ceria Coatings for Orthopedic Implants

Authors: Ayda Khosravanihaghighi, Pramod Koshy, Bill Walsh, Vedran Lovric, Charles Christopher Sorrell

Abstract:

There is an increasing demand for orthopedic implants owing to the increasing numbers of the aging population. Titanium alloy (Ti6Al4V) is a common material used for orthopedic implants owing to its advantageous properties in terms of good corrosion resistance, minimal elastic modulus mismatch with bone, bio-inertness, and high mechanical strength. However, it is important to improve the bioactivity and osseointegration of the titanium alloy and this can be achieved by coating the implant surface with suitable ceramic materials. In the present work, pure and doped-ceria (CeO₂) coatings were deposited by spin coating on the titanium alloy surface in order to enhance the biological interactions between the surface of the implant and the surrounding tissue. In order to examine the bone-binding ability of an implant, simulated body fluid (SBF) tests were conducted in order to assess the capability of apatite layer formation on the surface and thus predict in vivo bone bioactivity. Characterization was done using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses to determine the extent of apatite formation. Preliminary tests showed that the CeO₂ coatings were biocompatible and that the extent of apatite formation and its characteristics can be enhanced by doping with suitable metal ions.

Keywords: apatite layer, biocompatibility, ceria, orthopaedic implant, SBF, spin coater, Ti-implant

Procedia PDF Downloads 143
2439 Issues of Time's Urgency and Ritual in Children's Picture Books: A Closer Look at the Contributions of Grandparents

Authors: Karen Armstrong

Abstract:

Although invisible and fleeting, time is an essential variable in perception. Ritual is proposed as an antithesis to the passage of time, a way of linking our narratives with the past, present and future. This qualitative exploration examines a variety of award winning twentieth-century children’s picture books, specifically regarding the issues of time’s urgency and ritual with respect to children and grandparents. The paper will begin with a consideration of issues of time from the area of psychology, with regard to age, specifically contrasting later age and childhood. Next the value of ritual as represented by the presence of grandparents in children’s books. Specific instances of the contributions of grandparents or older adults with regard to this balancing function between time’s urgency and ritual will be discussed. Recommendations for future research include a consideration of grandparents’ or older characters’ depictions in books for older children.

Keywords: children's picture books, grandparents, ritual, time

Procedia PDF Downloads 293
2438 Migration as a Climate Change Adaptation Strategy: A Conceptual Equation for Analysis

Authors: Elisha Kyirem

Abstract:

Undoubtedly, climate change is a major global challenge that could threaten the very foundation upon which life on earth is anchored, with its impacts on human mobility attracting the attention of policy makers and researchers. There is an increasing body of literature and case studies suggesting that migration could be a way through which the vulnerable move away from areas exposed to climate extreme events to improve their lives and that of their families. This presents migration as a way through which people voluntarily move to seek opportunities that could help reduce their exposure and avoid danger from climate events. Thus, migration is seen as a proactive adaptation strategy aimed at building resilience and improving livelihoods to enable people to adapt to future changing events. However, there has not been any mathematical equation linking migration and climate change adaptation. Drawing from literature in development studies, this paper develops an equation that seeks to link the relationship between migration and climate change adaptation. The mathematical equation establishes the linkages between migration, resilience, poverty reduction and vulnerability, and these the paper maintains, are the key variables for conceptualizing the migration-climate change adaptation nexus. The paper then tests the validity of the equation using the sustainable livelihood framework and publicly available data on migration and tourism in Ghana.

Keywords: migration, adaptation, climate change, adaptation, poverty reduction

Procedia PDF Downloads 379
2437 The Role of MAOA Gene in the Etiology of Autism Spectrum Disorder in Males

Authors: Jana Kisková, Dana Gabriková

Abstract:

Monoamine oxidase A gene (MAOA) is suggested to be a candidate gene implicated in many neuropsychiatric disorders, including autism spectrum disorder (ASD). This meta-analytic review evaluates the relationship between ASD and MAOA markers such as 30 bp variable number tandem repeats in the promoter region (uVNTR) and single nucleotide polymorphisms (SNPs) by using findings from recently published studies. It seems that in Caucasian males, the risk of developing ASD increase with the presence of 4-repeat allele in the promoter region of MAOA gene whereas no differences were found between autistic patients and controls in Egyptian, West Bengal and Korean population. Some studies point to the importance specific haplotype groups of SNPs and interaction of MAOA with others genes (e.g. FOXP2 or SRY). The results of existing studies are insufficient and further research is needed.

Keywords: autism spectrum disorder, MAOA, uVNTR, single nucleotide polymorphism

Procedia PDF Downloads 377
2436 Cylindrical Spacer Shape Optimization for Enhanced Inhalation Therapy

Authors: Shahab Azimi, Siamak Arzanpour, Anahita Sayyar

Abstract:

Asthma and Chronic obstructive pulmonary disease (COPD) are common lung diseases that have a significant global impact. Pressurized metered dose inhalers (pMDIs) are widely used for treatment, but they can have limitations such as high medication release speed resulting in drug deposition in the mouth or oral cavity and difficulty achieving proper synchronization with inhalation by users. Spacers are add-on devices that improve the efficiency of pMDIs by reducing the release speed and providing space for aerosol particle breakup to have finer and medically effective medication. The aim of this study is to optimize the size and cylindrical shape of spacers to enhance their drug delivery performance. The study was based on fluid dynamics theory and employed Ansys software for simulation and optimization. Results showed that optimization of the spacer's geometry greatly influenced its performance and improved drug delivery. This study provides a foundation for future research on enhancing the efficiency of inhalation therapy for lung diseases.

Keywords: asthma, COPD, pressurized metered dose inhalers, spacers, CFD, shape optimization

Procedia PDF Downloads 78
2435 Corporate Governance and Financial Performance: Evidence From Indonesian Islamic Banks

Authors: Ummu Salma Al Azizah, Herri Mulyono, Anisa Mauliata Suryana

Abstract:

The significance of corporate governance regarding to the agency problem have been transparent. This study examine the impact of corporate governance on the performance of Islamic banking in Indonesia. By using fixed effect model and added some control variable, the current study try to explore the correlation between the theoretical framework on corporate governance, such as agency theory and risk management theory. The bank performance (Return on Asset and Return on Equity) which are operational performance and financial performance. And Corporate governance based on Board size, CEO duality, Audit committee and Shariah supervisory board. The limitation of this study only focus on the Islamic banks performance from year 2015 to 2020. The study fill the gap in the literature by addressing the issue of corporate governance on Islamic banks performance in Indonesia.

Keywords: corporate governance, financial performance, islamic banks, listed companies, Indonesia

Procedia PDF Downloads 107
2434 Internet of Things: Route Search Optimization Applying Ant Colony Algorithm and Theory of Computer Science

Authors: Tushar Bhardwaj

Abstract:

Internet of Things (IoT) possesses a dynamic network where the network nodes (mobile devices) are added and removed constantly and randomly, hence the traffic distribution in the network is quite variable and irregular. The basic but very important part in any network is route searching. We have many conventional route searching algorithms like link-state, and distance vector algorithms but they are restricted to the static point to point network topology. In this paper we propose a model that uses the Ant Colony Algorithm for route searching. It is dynamic in nature and has positive feedback mechanism that conforms to the route searching. We have also embedded the concept of Non-Deterministic Finite Automata [NDFA] minimization to reduce the network to increase the performance. Results show that Ant Colony Algorithm gives the shortest path from the source to destination node and NDFA minimization reduces the broadcasting storm effectively.

Keywords: routing, ant colony algorithm, NDFA, IoT

Procedia PDF Downloads 433
2433 Real-Time Nonintrusive Heart Rate Measurement: Comparative Case Study of LED Sensorics' Accuracy and Benefits in Heart Monitoring

Authors: Goran Begović

Abstract:

In recent years, many researchers are focusing on non-intrusive measuring methods when it comes to human biosignals. These methods provide solutions for everyday use, whether it’s health monitoring or finessing the workout routine. One of the biggest issues with these solutions is that the sensors’ accuracy is highly variable due to many factors, such as ambiental light, skin color diversity, etc. That is why we wanted to explore different outcomes under those kinds of circumstances in order to find the most optimal algorithm(s) for extracting heart rate (HR) information. The optimization of such algorithms can benefit the wider, cheaper, and safer application of home health monitoring, without having to visit medical professionals as often when it comes to observing heart irregularities. In this study, we explored the accuracy of infrared (IR), red, and green LED sensorics in a controlled environment and compared the results with a medically accurate ECG monitoring device.

Keywords: data science, ECG, heart rate, holter monitor, LED sensors

Procedia PDF Downloads 118
2432 Academic Staff Recruitment in Islamic University: A Proposed Holistic Model

Authors: Syahruddin Sumardi, Indra Fajar Alamsyah, Junaidah Hashim

Abstract:

This study attempts to explore and presents a proposed recruitment model in Islamic university which aligned with holistic role. It is a conceptual paper in nature. In turn, this study is designed to utilize exploratory approach. Literature and document review that related to this topic are used as the methods to analyse the content found. Recruitment for any organization is fundamental to achieve its goal effectively. Staffing in universities is vital due to the importance role of lecturers. Currently, Islamic universities still adopt the common process of recruitment for their academic staffs. Whereas, they have own characteristics which are embedded in their institutions. Furthermore, the FCWC (Foundation, Capability, Worldview and Commitment) model of recruitment proposes to suit the holistic character of Islamic university. Further studies are required to empirically validate the concept through systematic investigations. Additionally, measuring this model by a designed means is appreciated. The model provides the map and alternative tool of recruitment for Islamic universities to determine the process of recruitment which can appropriate their institutions. In addition, it also allows stakeholders and policy makers to consider regarding Islamic values that should inculcate in the Islamic higher learning institutions. This study initiates a foundational contribution for an early sequence of research.

Keywords: academic staff, Islamic values, recruitment model, university

Procedia PDF Downloads 155
2431 Numerical Analysis of a Mechanism for the Morphology in the Extrados of an Airfoil

Authors: E. R. Jimenez Barron, M. Castillo Morales, D. F. Ramírez Morales

Abstract:

The study of the morphology (shape change) in wings leads to the optimization of aerodynamic characteristics in an aircraft, so for the development and implementation of a change in the structure and shape of an airfoil, in this case the extrados, helps to increase the aerodynamic performance of an aircraft at different operating velocities, according to the required mission profile. A previous work on morphology is continued where the 'initial' profile is the NACA 4415 and as a new profile 'objective' the FUSION. The objective of this work is the dimensioning of the elements of the mechanism used to achieve the required changes. We consulted the different materials used in the aeronautics industry, as well as new materials in this area that could contribute to the good performance of the mechanism without negatively affecting the aerodynamics. These results allow evaluating the performance of a wing with variable extrados with respect to the defined morphology.

Keywords: numerical analysis, mechanisms, morphing airfoil, morphing wings

Procedia PDF Downloads 221
2430 Research on Optimization Strategies for the Negative Space of Urban Rail Transit Based on Urban Public Art Planning

Authors: Kexin Chen

Abstract:

As an important method of transportation to solve the demand and supply contradiction generated in the rapid urbanization process, urban rail traffic system has been rapidly developed over the past ten years in China. During the rapid development, the space of urban rail Transit has encountered many problems, such as space simplification, sensory experience dullness, and poor regional identification, etc. This paper, focus on the study of the negative space of subway station and spatial softening, by comparing and learning from foreign cases. The article sorts out cases at home and abroad, make a comparative study of the cases, analysis more diversified setting of public art, and sets forth propositions on the domestic type of public art in the space of urban rail transit for reference, then shows the relationship of the spatial attribute in the space of urban rail transit and public art form. In this foundation, it aims to characterize more diverse setting ways for public art; then suggests the three public art forms corresponding properties, such as static presenting mode, dynamic image mode, and spatial softening mode; finds out the method of urban public art to optimize negative space.

Keywords: diversification, negative space, optimization strategy, public art planning

Procedia PDF Downloads 198
2429 Analysis of Simple Mechanisms to Continuously Vary Mach Number in a Supersonic Wind Tunnel Facility

Authors: Prateek Kishore, T. M. Muruganandam

Abstract:

Supersonic wind tunnel nozzles are generally capable of producing a constant Mach number flow in the test section of the wind tunnel. As a result, most of the supersonic vehicles are widely designed using steady state flow characteristics which may have errors while facing unsteady situations. This study aims to explore the possibility of varying the Mach number of the flow during wind tunnel operation. The nozzle walls are restricted to be inflexible for cooling near the throat due to high stagnation temperature requirement of the flow to simulate the conditions as experienced by the vehicle. Two simple independent mechanisms, rotation and translation of nozzle walls have been analyzed and the nozzle ranges have been optimized to vary the Mach number from Mach 2 to Mach 5 using minimum number of nozzles in the wind tunnel.

Keywords: method of characteristics, nozzle, supersonic wind tunnel, variable mach number

Procedia PDF Downloads 281
2428 Antifungal Activity of Commiphora myrrha L. against Some Air Fungi

Authors: Ahmed E. Al-Sabri, Mohamed A. Moslem, Sarfaraz Hadi

Abstract:

To avoid the harmful effects of the chemical fungicides on the human and minimize the environmental pollution, an alternative eco-friendly control strategies should be developed. The extract of Commiphora myhrra L. was tested against twenty fungal genera isolated from the indoor air collected from different rooms in King Saud University, Kingdom of Saudi Arabia. Disc diffusion test was modified for use in this study and the collected data was statistically analyzed. Variable antifungal efficacy of different myrrh extract was recorded against the investigated fungal genera. The efficacy of the extract was increased as the concentration increased. The highest growth inhibition (74.6%) was against Acremonium strictum followed by Trichoderma psuedokoningii (70.6%). On contrast, the lowest efficacy (12.7%) was against Ulocladium consortiale. It could be concluded that myrrh extract is promised as a source of substances from which of safer and eco-friendly could be used as antimicrobial agents against a number of pathogenic fungi.

Keywords: antifungal, myrrh, antimicrobial, medicinal plant

Procedia PDF Downloads 406
2427 Effect of Supply Frequency on Pre-Breakdown and Breakdown Phenomena in Unbridged Vacuum Gaps

Authors: T.C. Balachandra, Habibuddin Shaik

Abstract:

This paper presents experimental results leading towards a better understanding of pre-breakdown and breakdown behavior of vacuum gaps under variable frequency alternating excitations. The frequency variation is in the range of 30 to 300 Hz in steps of 10 Hz for a fixed gap spacing of 0.5 mm. The results indicate that the pre-breakdown currents show an inverse relation with the breakdown voltage in general though erratic behavior was observed over a certain range of frequencies. A breakdown voltage peak was observed at 130 Hz. This was pronounced when the electrode pair was of stainless steel and less pronounced when copper and aluminum electrodes were used. The experimental results are explained based on F-N emission, I-F emission, and also thermal interaction due to quasi-continuous shower of anode micro-particles. Further, it is speculated that the ostensible cause for time delay between voltage and current peaks is due to the presence of neutral molecules in the gap.

Keywords: anode hot-spots, F-N emission, I-F emission, microparticle, neutral molecules, pre-breakdown conduction, vacuum breakdown

Procedia PDF Downloads 147
2426 Empirical Green’s Function Technique for Accelerogram Synthesis: The Problem of the Use for Marine Seismic Hazard Assessment

Authors: Artem A. Krylov

Abstract:

Instrumental seismological researches in water areas are complicated and expensive, that leads to the lack of strong motion records in most offshore regions. In the same time the number of offshore industrial infrastructure objects, such as oil rigs, subsea pipelines, is constantly increasing. The empirical Green’s function technique proved to be very effective for accelerograms synthesis under the conditions of poorly described seismic wave propagation medium. But the selection of suitable small earthquake record in offshore regions as an empirical Green’s function is a problem because of short seafloor instrumental seismological investigation results usually with weak micro-earthquakes recordings. An approach based on moving average smoothing in the frequency domain is presented for preliminary processing of weak micro-earthquake records before using it as empirical Green’s function. The method results in significant waveform correction for modeled event. The case study for 2009 L’Aquila earthquake was used to demonstrate the suitability of the method. This work was supported by the Russian Foundation of Basic Research (project № 18-35-00474 mol_a).

Keywords: accelerogram synthesis, empirical Green's function, marine seismology, microearthquakes

Procedia PDF Downloads 312
2425 Thermography Evaluation on Facial Temperature Recovery after Elastic Gum

Authors: A. Dionísio, L. Roseiro, J. Fonseca, P. Nicolau

Abstract:

Thermography is a non-radiating and contact-free technology which can be used to monitor skin temperature. The efficiency and safety of thermography technology make it a useful tool for detecting and locating thermal changes in skin surface, characterized by increases or decreases in temperature. This work intends to be a contribution for the use of thermography as a methodology for evaluation of skin temperature in the context of orofacial biomechanics. The study aims to identify the oscillations of skin temperature in the left and right hemiface regions of the masseter muscle, during and after thermal stimulus, and estimate the time required to restore the initial temperature after the application of the stimulus. Using a FLIR T430sc camera, a data acquisition protocol was followed with a group of eight volunteers, aged between 22 and 27 years. The tests were performed in a controlled environment with the volunteers in a comfortably static position. The thermal stimulus involves the use of an ice volume with controlled size and contact surface. The skin surface temperature was recorded in two distinct situations, namely without further stimulus and with the additions of a stimulus obtained by a chewing gum. The data obtained were treated using FLIR Research IR Max software. The time required to recover the initial temperature ranged from 20 to 52 minutes when no stimulus was added and varied between 8 and 26 minutes with the chewing gum stimulus. These results show that recovery is faster with the addition of the stimulus and may guide clinicians regarding the pre and post-operative times with ice therapy, in the presence or absence of mechanical stimulus that increases muscle functions (e.g. phonetics or mastication).

Keywords: thermography, orofacial biomechanics, skin temperature, ice therapy

Procedia PDF Downloads 241
2424 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 262
2423 Variable Tree Structure QR Decomposition-M Algorithm (QRD-M) in Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) Systems

Authors: Jae-Hyun Ro, Jong-Kwang Kim, Chang-Hee Kang, Hyoung-Kyu Song

Abstract:

In multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) systems, QR decomposition-M algorithm (QRD-M) has suboptimal error performance. However, the QRD-M has still high complexity due to many calculations at each layer in tree structure. To reduce the complexity of the QRD-M, proposed QRD-M modifies existing tree structure by eliminating unnecessary candidates at almost whole layers. The method of the elimination is discarding the candidates which have accumulated squared Euclidean distances larger than calculated threshold. The simulation results show that the proposed QRD-M has same bit error rate (BER) performance with lower complexity than the conventional QRD-M.

Keywords: complexity, MIMO-OFDM, QRD-M, squared Euclidean distance

Procedia PDF Downloads 323
2422 Development of an Auxetic Tissue Implant

Authors: Sukhwinder K. Bhullar, M. B. G. Jun

Abstract:

The developments in biomedical industry have demanded the development of biocompatible, high performance materials to meet higher engineering specifications. The general requirements of such materials are to provide a combination of high stiffness and strength with significant weight savings, resistance to corrosion, chemical resistance, low maintenance, and reduced costs. Auxetic materials which come under the category of smart materials offer huge potential through measured enhancements in mechanical properties. Unique deformation mechanism, providing cushioning on indentation, automatically adjustable with its strength and thickness in response to forces and having memory returns to its neutral state on dissipation of stresses make them good candidate in biomedical industry. As simple extension and compression of tissues is of fundamental importance in biomechanics, therefore, to study the elastic behaviour of auxetic soft tissues implant is targeted in this paper. Therefore development and characterization of auxetic soft tissue implant is studied in this paper. This represents a real life configuration where soft tissue such as meniscus in knee replacement, ligaments and tendons often are taken as transversely isotropic. Further, as composition of alternating polydisperse blocks of soft and stiff segments combined with excellent biocompatibility make polyurethanes one of the most promising synthetic biomaterials. Hence selecting auxetic polyurathylene foam functional characterization is performed and compared with conventional polyurathylene foam.

Keywords: auxetic materials, deformation mechanism, enhanced mechanical properties, soft tissues

Procedia PDF Downloads 452
2421 The Evolution of National Technological Capability Roles From the Perspective of Researcher’s Transfer: A Case Study of Artificial Intelligence

Authors: Yating Yang, Xue Zhang, Chengli Zhao

Abstract:

Technology capability refers to the comprehensive ability that influences all factors of technological development. Among them, researchers’ resources serve as the foundation and driving force for technology capability, representing a significant manifestation of a country/region's technological capability. Therefore, the cross-border transfer behavior of researchers to some extent reflects changes in technological capability between countries/regions, providing a unique research perspective for technological capability assessment. This paper proposes a technological capability assessment model based on personnel transfer networks, which consists of a researchers' transfer network model and a country/region role evolution model. It evaluates the changes in a country/region's technological capability roles from the perspective of researcher transfers and conducts an analysis using artificial intelligence as a case study based on literature data. The study reveals that the United States, China, and the European Union are core nodes, and identifies the role evolution characteristics of several major countries/regions.

Keywords: transfer network, technological capability assessment, central-peripheral structure, role evolution

Procedia PDF Downloads 71
2420 Parameter Estimation of False Dynamic EIV Model with Additive Uncertainty

Authors: Dalvinder Kaur Mangal

Abstract:

For the past decade, noise corrupted output measurements have been a fundamental research problem to be investigated. On the other hand, the estimation of the parameters for linear dynamic systems when also the input is affected by noise is recognized as more difficult problem which only recently has received increasing attention. Representations where errors or measurement noises/disturbances are present on both the inputs and outputs are usually called errors-in-variables (EIV) models. These disturbances may also have additive effects which are also considered in this paper. Parameter estimation of false EIV problem using equation error, output error and iterative prefiltering identification schemes with and without additive uncertainty, when only the output observation is corrupted by noise has been dealt in this paper. The comparative study of these three schemes has also been carried out.

Keywords: errors-in-variable (EIV), false EIV, equation error, output error, iterative prefiltering, Gaussian noise

Procedia PDF Downloads 477