Search results for: internal cooling
1548 Wave Propagation In Functionally Graded Lattice Structures Under Impact Loads
Authors: Mahmood Heshmati, Farhang Daneshmand
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Material scientists and engineers have introduced novel materials with complex geometries due to the recent technological advances and promotion of manufacturing methods. Among them, lattice structures with graded architectures denoted by functionally graded porous materials (FGPMs) have been developed to optimize the structural response. FGPMs are achieved by tailoring the size and density of the internal pores in one or more directions that lead to the desired mechanical properties and structural responses. Also, FGPMs provide more flexible transition and the possibility of designing and fabricating structural elements with complex and variable properties. In this paper, wave propagation in lattice structures with functionally graded (FG) porosity is investigated in order to examine the ability of shock absorbing effect. The behavior of FG porous beams with different porosity distributions under impact load and the effects of porosity distribution and porosity content on the wave speed are studied. Important conclusions are made, along with a discussion of the future scope of studies on FGPMs structures.Keywords: functionally graded, porous materials, wave propagation, impact load, finite element
Procedia PDF Downloads 951547 Spray Characteristics of a Urea Injector Chamber to Improve NOx Conversion Efficiency for Diesel Engines Fueled with Biodiesels
Authors: Kazem Bashirnezhad, Seyed Ahmad Kebriyaee, saeed hoseyngholizadeh moghadam
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The urea–SCR catalyst system has the advantages of high NOx conversion efficiency and a wide range of operating conditions. The key factors for successful implementation of urea–SCR technology is good mixing of urea (ammonia) and gas to reduce ammonia slip. Urea mixer components are required to facilitate evaporation and mixing, because it is difficult to evaporate urea in the liquid state; the injection parameters are the most critical factors affecting mixer performance. In this study, The effect of urea injection on NOx emissions in a six-cylinder, four-stroke internal combustion engine fueled with B80 biodiesel has been experimentally investigated. The results reveal that urea injection leads to a reduction of NOx emissions of B80 biodiesel fuel. Moreover, the influence of injection parameters on NOx reductions has been studied. The findings show that by increasing the injection temperature, more reduction in NOx emissions has been occurred. Also, urea mass flow rate increment leads to more NOx reduction. The same result has been obtained by an increase in spray angle.Keywords: urea, NOx emissions, diesel engines, biodiesels
Procedia PDF Downloads 4971546 Controlled Mobile Platform for Service Based Humanoid Robot System
Authors: Shrikant V. Sangludkar, Dilip I. Sangotra, Sachin T. Bagde, Abhijeet A. Khandagale
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The paper discloses a controlled tracked humanoid robot moving platform. A driving and driven wheel are controlled by a control module to drive a robot body to move according to data signals of a monitoring module, in addition, remote transmission can be achieved, and a certain remote control function can be realized. A power management module circuit board looks after in used for providing electric drive for moving of the robot body and distribution of separate power source to be used in internal of robot system. An external port circuit board is arranged, the tracked robot moving platform can be used immediately for any data acquisition. The moving platform is simple and compact in structure, strong in adaptation performance, stable in operation and suitable for being operated in severe environments. Meanwhile, a layered modular installation structure is adopted, and therefore the moving platform is convenient to assemble and disassemble.Keywords: moving platform, humanoid robot, embedded controlled drive, mobile robot, museum robots, self-localization, obstacle avoidance, communication
Procedia PDF Downloads 4301545 Coordinated Community Response to Intimate Partner Violence on College Campuses
Authors: Robert D. Hanser, Gina M. Hanser
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This paper provides an overview of Coordinated Community Response Teams (CCRT) to Intimate Partner Violence (IPV). The CCRT, as a partnership and collaborative effort between multiple agencies is highlighted. This paper is a legal analysis that showcases new legislation and legal requirements in the United States for investigating, processing, and reporting to acts of victimization have transformed the role of the university’s CCRT on campus, making its mission all the more important, both internal and external to the campus. As a specific example, discussion of the CCRT in Northeast Louisiana at the University of Louisiana at Monroe is provided as an example of involvement in this initiative, where federal grant funding has allowed a micro version of the region’s CCRT to be implemented on that campus. Simultaneously, university personnel also work with external agencies throughout the community in intimate partner violence response. Amidst this, the result is a genuine partnership between practitioners and researchers who work together to provide public awareness, prevention, first-responder, and intervention services in a comprehensive manner throughout Northeast Louisiana.Keywords: interperaonal violence, sexual assault, dating violence, campus violence
Procedia PDF Downloads 3111544 The Effect of Metal Transfer Modes on Mechanical Properties of 3CR12 Stainless Steel
Authors: Abdullah Kaymakci, Daniel M. Madyira, Ntokozo Nkwanyana
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The effect of metal transfer modes on mechanical properties of welded 3CR12 stainless steel were investigated. This was achieved by butt welding 10 mm thick plates of 3CR12 in different positions while varying the welding positions for different metal transfer modes. The ASME IX: 2010 (Welding and Brazing Qualifications) code was used as a basis for welding variables. The material and the thickness of the base metal were kept constant together with the filler metal, shielding gas and joint types. The effect of the metal transfer modes on the microstructure and the mechanical properties of the 3CR12 steel was then investigated as it was hypothesized that the change in welding positions will affect the transfer modes partly due to the effect of gravity. The microscopic examination revealed that the substrate was characterized by dual phase microstructure, that is, alpha phase and beta phase grain structures. Using the spectroscopic examination results and the ferritic factor calculation had shown that the microstructure was expected to be ferritic-martensitic during air cooling process. The tested tensile strength and Charpy impact energy were measured to be 498 MPa and 102 J which were in line with mechanical properties given in the material certificate. The heat input in the material was observed to be greater than 1 kJ/mm which is the limiting factor for grain growth during the welding process. Grain growths were observed in the heat affected zone of the welded materials. Ferritic-martensitic microstructure was observed in the microstructure during the microscopic examination. The grain growth altered the mechanical properties of the test material. Globular down hand had higher mechanical properties than spray down hand. Globular vertical up had better mechanical properties than globular vertical down.Keywords: welding, metal transfer modes, stainless steel, microstructure, hardness, tensile strength
Procedia PDF Downloads 2531543 Housing Security System and Household Entrepreneurship: Evidence from China
Authors: Wangshi Yong, Wei Shi, Jing Zou, Qiang Li, Yilin Tian
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With the advancement of the reform of China’s housing security system, the impact is becoming increasingly profound. This paper explores the relationship between the housing security system and household entrepreneurship on the 2017 China Household Finance Survey (CHFS) and conducts a large number of robustness checks, including PSM and IV estimation. The results show that the assistance of the housing security system will significantly promote family entrepreneurship, increasing the probability of entrepreneurship by 2%. Its internal mechanism is mainly achieved by relaxing liquidity constraints and increasing household social capital. However, the risk preference effect has not existed. Heterogeneity analysis shows that the positive impact of the housing security system on family entrepreneurship is mainly reflected in areas with high housing prices and incomes, as well as households with long-term security and social or commercial insurance. Meanwhile, it also verifies that the positive externalities of the housing security system will also positively affect active entrepreneurial motivation, entrepreneurial intensity, and entrepreneurial innovation.Keywords: the housing security system, household entrepreneurship, social capital, liquidity constraints, risk preference
Procedia PDF Downloads 861542 Operating System Support for Mobile Device Thermal Management and Performance Optimization in Augmented Reality Applications
Authors: Yasith Mindula Saipath Wickramasinghe
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Augmented reality applications require a high processing power to load, render and live stream high-definition AR models and virtual scenes; it also requires device sensors to work excessively to coordinate with internal hardware, OS and give the expected outcome in advance features like object detection, real time tracking, as well as voice and text recognition. Excessive thermal generation due to these advanced functionalities has become a major research problem as it is unbearable for smaller mobile devices to manage such heat increment and battery drainage as it causes physical harm to the devices in the long term. Therefore, effective thermal management is one of the major requirements in Augmented Reality application development. As this paper discusses major causes for this issue, it also provides possible solutions in the means of operating system adaptations as well as further research on best coding practises to optimize the application performance that reduces thermal excessive thermal generation.Keywords: augmented reality, device thermal management, GPU, operating systems, device I/O, overheating
Procedia PDF Downloads 1211541 Love and Loss: The Emergence of Shame in Romantic Information Communication Technology
Authors: C. Caudwell, R. Syed, C. Lacey
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While the development and advancement of information communication technologies (ICTs) offers powerful opportunities for meaningful connections and relationships, shame is a significant barrier to social and cultural acceptance. In particular, artificial intelligence and socially oriented robots are increasingly becoming partners in romantic relationships with people, offering bonding, support, comfort, growth, and reciprocity. However, these relationships suffer hierarchical, anthropocentric shame that is a significant barrier to their success and longevity. This paper will present case studies of human and artificially intelligent agent relationships, in the context of internal and external shame, as cultivated, propagated, and communicated through ICT. Using an interdisciplinary methodology we aim to present a framework for technological shame, building on the experimental and emergent psychoanalytical theories of emotions. Our study finds principally that socialization is a powerful factor in the vectors of shame as experienced by humans. On a wider scale, we contribute understanding of social emotion and the phenomenon of shame proliferated through ICTs, which is at present under-explored, but vital, as society and culture is increasingly mediated through this medium.Keywords: shame, artificial intelligence, romance, society
Procedia PDF Downloads 1361540 Influence of Corrugation and Loosely Bonded Interface on the Propagation of Torsional Wave Propagation in a Viscoelastic Layer
Authors: Amrita Das, Abhishek Kumar Singh
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The present paper calibrates the efficacy of corrugated and loosely bonded common interface of a viscoelastic layer and a dry sandy Gibson half-space on the propagation of torsional surface wave. Using suitable boundary conditions, the dispersion relation for the concerned problem is deduced in complex form. Numerical computation of the real part of the obtained dispersion relation gives the dispersion curve whereas the imaginary part bestows the damping curves. The use of Whittaker’s function and Bessel’s functions are among the major concerns of the paper. The investigation of the influence of the affecting parameters viz. heterogeneities, sandiness, Biot’s gravity parameter, initial stresses, loosely bonded interface, corrugation and internal friction on the phase velocity as well as damped velocity of torsional wave, through numerical discussion and graphical illustration, is among the major highlights of the current study.Keywords: corrugation, dry sandy Gibson half-space, loosely bonded interface, torsional wave, viscoelastic layer
Procedia PDF Downloads 3271539 Understanding the Perceived Barriers and Facilitators to Exercise Participation in the Workplace
Authors: Jayden R. Hunter, Brett A. Gordon, Stephen R. Bird, Amanda C. Benson
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The World Health Organisation recognises the workplace as an important setting for exercise promotion, with potential benefits including improved employee health and fitness, and reduced worker absenteeism and presenteeism. Despite these potential benefits to both employee and employer, there is a lack of evidence supporting the long-term effectiveness of workplace exercise programs. There is, therefore, a need for better-informed programs that cater to employee exercise preferences. Specifically, workplace exercise programs should address any time, motivation, internal and external barriers to participation reported by sub-groups of employees. This study sought to compare exercise participation to perceived barriers and facilitators to workplace exercise engagement of university employees. This information is needed to design and implement wider-reaching programs aiming to maximise long-term employee exercise adherence and subsequent health, fitness and productivity benefits. An online survey was advertised at an Australian university with the potential to reach 3,104 full-time employees. Along with exercise participation (International physical activity questionnaire) and behaviour (stage of behaviour change in relation to physical activity questionnaire), perceived barriers (corporate exercise barriers scale) and facilitators to workplace exercise participation were identified. The survey response rate was 8.1% (252 full-time employees; 95% white-collar; 60% female; 79.4% aged 30–59 years; 57% professional and 38% academic). Most employees reported meeting (43.7%) or exceeding (42.9%) exercise guidelines over the previous week (i.e. ⩾30 min of moderate-intensity exercise on most days or ⩾ 25 min of vigorous-intensity exercise on at least three days per week). Reported exercise behaviour over the previous six months showed that 64.7% of employees were in maintenance, 8.3% were in action, 10.9% were in preparation, 12.4% were in contemplation, and 3.8% were in the pre-contemplation stage of change. Perceived barriers towards workplace exercise participation were significantly higher in employees not attaining weekly exercise guidelines compared to employees meeting or exceeding guidelines, including a lack of time or reduced motivation (p < 0.001; partial eta squared = 0.24 (large effect)), exercise attitude (p < 0.05; partial eta squared = 0.04 (small effect)), internal (p < 0.01; partial eta squared = 0.10 (moderate effect)) and external (p < 0.01; partial eta squared = 0.06 (moderate effect)) barriers. The most frequently reported exercise facilitators were personal training (particularly for insufficiently active employees; 33%) and group exercise classes (20%). The most frequently cited preferred modes of exercise were walking (70%), swimming (50%), gym (48%), and cycling (45%). In conclusion, providing additional means of support such as individualised gym, swimming and cycling programs with personal supervision and guidance may be particularly useful for employees not meeting recommended moderate-vigorous volumes of exercise, to help overcome reported exercise barriers in order to improve participation, health, and fitness. While individual biopsychosocial factors should be considered when making recommendations for interventions, the specific barriers and facilitators to workplace exercise participation identified by this study can inform the development of workplace exercise programs aiming to broaden employee engagement and promote greater ongoing exercise adherence. This is especially important for the uptake of less active employees who perceive greater barriers to workplace exercise participation than their more active colleagues.Keywords: exercise barriers, exercise facilitators, physical activity, workplace health
Procedia PDF Downloads 1471538 The Non-Linear Analysis of Brain Response to Visual Stimuli
Authors: H. Namazi, H. T. N. Kuan
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Brain activity can be measured by acquiring and analyzing EEG signals from an individual. In fact, the human brain response to external and internal stimuli is mapped in his EEG signals. During years some methods such as Fourier transform, wavelet transform, empirical mode decomposition, etc. have been used to analyze the EEG signals in order to find the effect of stimuli, especially external stimuli. But each of these methods has some weak points in analysis of EEG signals. For instance, Fourier transform and wavelet transform methods are linear signal analysis methods which are not good to be used for analysis of EEG signals as nonlinear signals. In this research we analyze the brain response to visual stimuli by extracting information in the form of various measures from EEG signals using a software developed by our research group. The used measures are Jeffrey’s measure, Fractal dimension and Hurst exponent. The results of these analyses are useful not only for fundamental understanding of brain response to visual stimuli but provide us with very good recommendations for clinical purposes.Keywords: visual stimuli, brain response, EEG signal, fractal dimension, hurst exponent, Jeffrey’s measure
Procedia PDF Downloads 5651537 Determination of Temperature Dependent Characteristic Material Properties of Commercial Thermoelectric Modules
Authors: Ahmet Koyuncu, Abdullah Berkan Erdogmus, Orkun Dogu, Sinan Uygur
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Thermoelectric modules are integrated to electronic components to keep their temperature in specific values in electronic cooling applications. They can be used in different ambient temperatures. The cold side temperatures of thermoelectric modules depend on their hot side temperatures, operation currents, and heat loads. Performance curves of thermoelectric modules are given at most two different hot surface temperatures in product catalogs. Characteristic properties are required to select appropriate thermoelectric modules in thermal design phase of projects. Generally, manufacturers do not provide characteristic material property values of thermoelectric modules to customers for confidentiality. Common commercial software applied like ANSYS ICEPAK, FloEFD, etc., include thermoelectric modules in their libraries. Therefore, they can be easily used to predict the effect of thermoelectric usage in thermal design. Some software requires only the performance values in different temperatures. However, others like ICEPAK require three temperature-dependent equations for material properties (Seebeck coefficient (α), electrical resistivity (β), and thermal conductivity (γ)). Since the number and the variety of thermoelectric modules are limited in this software, definitions of characteristic material properties of thermoelectric modules could be required. In this manuscript, the method of derivation of characteristic material properties from the datasheet of thermoelectric modules is presented. Material characteristics were estimated from two different performance curves by experimentally and numerically in this study. Numerical calculations are accomplished in ICEPAK by using a thermoelectric module exists in the ICEPAK library. A new experimental setup was established to perform experimental study. Because of similar results of numerical and experimental studies, it can be said that proposed equations are approved. This approximation can be suggested for the analysis includes different type or brand of TEC modules.Keywords: electrical resistivity, material characteristics, thermal conductivity, thermoelectric coolers, seebeck coefficient
Procedia PDF Downloads 1811536 Effectiveness of an Intervention to Increase Physics Students' STEM Self-Efficacy: Results of a Quasi-Experimental Study
Authors: Stephanie J. Sedberry, William J. Gerace, Ian D. Beatty, Michael J. Kane
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Increasing the number of US university students who attain degrees in STEM and enter the STEM workforce is a national priority. Demographic groups vary in their rates of participation in STEM, and the US produces just 10% of the world’s science and engineering degrees (2014 figures). To address these gaps, we have developed and tested a practical, 30-minute, single-session classroom-based intervention to improve students’ self-efficacy and academic performance in University STEM courses. Self-efficacy is a psychosocial construct that strongly correlates with academic success. Self-efficacy is a construct that is internal and relates to the social, emotional, and psychological aspects of student motivation and performance. A compelling body of research demonstrates that university students’ self-efficacy beliefs are strongly related to their selection of STEM as a major, aspirations for STEM-related careers, and persistence in science. The development of an intervention to increase students’ self-efficacy is motivated by research showing that short, social-psychological interventions in education can lead to large gains in student achievement. Our intervention addresses STEM self-efficacy via two strong, but previously separate, lines of research into attitudinal/affect variables that influence student success. The first is ‘attributional retraining,’ in which students learn to attribute their successes and failures to internal rather than external factors. The second is ‘mindset’ about fixed vs. growable intelligence, in which students learn that the brain remains plastic throughout life and that they can, with conscious effort and attention to thinking skills and strategies, become smarter. Extant interventions for both of these constructs have significantly increased academic performance in the classroom. We developed a 34-item questionnaire (Likert scale) to measure STEM Self-efficacy, Perceived Academic Control, and Growth Mindset in a University STEM context, and validated it with exploratory factor analysis, Rasch analysis, and multi-trait multi-method comparison to coded interviews. Four iterations of our 42-week research protocol were conducted across two academic years (2017-2018) at three different Universities in North Carolina, USA (UNC-G, NC A&T SU, and NCSU) with varied student demographics. We utilized a quasi-experimental prospective multiple-group time series research design with both experimental and control groups, and we are employing linear modeling to estimate the impact of the intervention on Self-Efficacy,wth-Mindset, Perceived Academic Control, and final course grades (performance measure). Preliminary results indicate statistically significant effects of treatment vs. control on Self-Efficacy, Growth-Mindset, Perceived Academic Control. Analyses are ongoing and final results pending. This intervention may have the potential to increase student success in the STEM classroom—and ownership of that success—to continue in a STEM career. Additionally, we have learned a great deal about the complex components and dynamics of self-efficacy, their link to performance, and the ways they can be impacted to improve students’ academic performance.Keywords: academic performance, affect variables, growth mindset, intervention, perceived academic control, psycho-social variables, self-efficacy, STEM, university classrooms
Procedia PDF Downloads 1281535 A Mini-Review on Effect of Magnetic Field and Material on Combustion Engines
Authors: A. N. Santhosh, Vinay Hegde, S. Vinod Kumar, R. Giria, D. L. Rakesh, M. S. Raghu
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At present, research on automobile engineering is in high demand, particularly in the field of fuel combustion. A large number of fossil fuels are being used in combustion, which may get exhausted in the near future and are not economical. To this end, research on the use of magnetic material in combustion engines is in progress to enhance the efficiency of fuel. The present review describes the chemical, physical and mathematical theory behind the magnetic materials along with the working principle of the internal combustion engine. The effect of different magnets like ferrite magnet, Neodymium magnet, and electromagnets was discussed. The effect of magnetic field on the consumption of the fuel, brake thermal efficiency, carbon monoxide, Oxides of Nitrogen, carbon dioxide, and hydrocarbon emission, along with smoke density, have been discussed in detail. Detailed mathematical modelling that shows the effect of magnetic field on fuel combustion is elaborated. Required pictorial representations are included wherever necessary. This review article could serve as a base for studying the effect of magnetic materials on IC engines.Keywords: magnetic field, energizer, fuel conditioner, fuel consumption, emission reduction
Procedia PDF Downloads 1041534 Charged Momentum: Electric Vehicle Surge in India’s 2023 Landscape
Authors: Rahul Wagh, Sunil Shinde
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Electric vehicles (EVs) have emerged as a transformative force in India's transportation sector, offering a sustainable solution to the country's growing energy and environmental challenges. Against the backdrop of rapid urbanization, rising pollution levels, and the need for energy security, EVs have gained traction as a viable alternative to traditional internal combustion engine vehicles. This paper provides a comprehensive analysis of the electric vehicle market in India, focusing particularly on the landscape of 2023. It emphasizes key aspects such as the 2023 scenario of EV adoption, the role of indigenous manufacturers, dominant players shaping the market, and the influence of government policies and initiatives, including the FAME I and II schemes. Furthermore, the paper delves into EV sales data for the fiscal year 2023, offering insights into market trends and consumer preferences. By elucidating the current state of EVs in India, this paper aims to contribute to a deeper understanding of the country's transition towards sustainable mobility and its implications for energy, the environment, and the economy.Keywords: EV adoption 2023, FAME schemes, consumer preferences, market trends
Procedia PDF Downloads 151533 Family Dynamics on Attitude Towards Peace: The Mediating Role of Emotional Regulation Strategies
Authors: Nicole Kaye A. Callanta, Shalimar B. Baruang, Anne Edelienne P. Tadena, Imelu G. Mordeno, Odessa May D. Escalona
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Untold numbers of children and adolescents around the world are exposed increasingly to the war on a daily basis. These experiences shape how they will view themselves, others, and the world. A wealth of studies have shown the role of family dynamics in the development of children’s attitudes, particularly their social behaviors. This specific study, however, contends that family dynamics influence peace and conflict resolution attitude and further asserts that it is brought about by the degree of emotional regulation strategies they use. Utilising purposive sampling, adolescent participant-respondents were from different schools in Southern Philipines, specifically of the cities of Marawi and Iligan, where exposure to warring clans, internal struggle between the Philippine Military and insurgencies, and the recent Marawi Seige caused by Al-Qaeda and ISIS-spawned terrorism. Results showed emotional regulation strategies mediate the relationship between family dynamics, particularly on family cohesion, and attitude towards peace. Thus implying the association between family cohesion and attitude towards peace strengthens with the use of emotional regulation strategies.Keywords: attitude towards peace, emotional regulation strategies, family cohesion, family dynamics
Procedia PDF Downloads 1791532 Simultaneous Determination of p-Phenylenediamine, N-Acetyl-p-phenylenediamine and N,N-Diacetyl-p-phenylenediamine in Human Urine by LC-MS/MS
Authors: Khaled M. Mohamed
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Background: P-Phenylenediamine (PPD) is used in the manufacture of hair dyes and skin decoration. In some developing countries, suicidal, homicidal and accidental cases by PPD were recorded. In this work, a sensitive LC-MS/MS method for determination of PPD and its metabolites N-acetyl-p-phenylenediamine (MAPPD) and N,N-diacetyl-p-phenylenediamine (DAPPD) in human urine has been developed and validated. Methods: PPD, MAPPD and DAPPD were extracted from urine by methylene chloride at alkaline pH. Acetanilide was used as internal standard (IS). The analytes and IS were separated on an Eclipse XDB- C18 column (150 X 4.6 mm, 5 µm) using a mobile phase of acetonitrile-1% formic acid in gradient elution. Detection was performed by LC-MS/MS using electrospray positive ionization under multiple reaction-monitoring mode. The transition ions m/z 109 → 92, m/z 151 → 92, m/z 193 → 92, and m/z 136 → 77 were selected for the quantification of PPD, MAPPD, DAPPD, and IS, respectively. Results: Calibration curves were linear in the range 10–2000 ng/mL for all analytes. The mean recoveries for PPD, MAPPD and DAPPD were 57.62, 74.19 and 50.99%, respectively. Intra-assay and inter-assay imprecisions were within 1.58–9.52% and 5.43–9.45% respectively for PPD, MAPPD and DAPPD. Inter-assay accuracies were within -7.43 and 7.36 for all compounds. PPD, MAPPD and DAPPD were stable in urine at –20 degrees for 24 hours. Conclusions: The method was successfully applied to the analysis of PPD, MAPPD and DAPPD in urine samples collected from suicidal cases.Keywords: p-Phenylenediamine, metabolites, urine, LC-MS/MS, validation
Procedia PDF Downloads 3571531 Comparison of the Effects of Rod Types of Rigid Fixation Devices on the Loads in the Lumbar Spine: A Finite Element Analysis
Authors: Bokku Kang, Changsoo Chon, Han Sung Kim
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We developed new design of rod of pedicle screw system that is beneficial in maintaining the spacing between the vertebrae and assessed the performance of the posterior fixation screw systems by numerical analysis according to the range of motion (flexion, extension, lateral bending, and axial rotation) of the vertebral column after inserting the pedicle screws. The simulation results showed that the conventional rod was the most low equivalent stress value among implant units in the case of flexion, extension and lateral bending of the vertebrae. In all cases except the torsional rotation, the results showed that the stress level of the single and double rounded rod exceeded about 30% to 70% compare to the conventional rod. Therefore, this product is not suitable for actual application in the field yet and it seems that product design optimization is necessary. Acknowledgement: This research was supported by the Ministry of Trade, Industry & Energy (MOTIE), Korea Institute for Advancement of Technology (KIAT) through the Encouragement Program for The Industries of Economic Cooperation Region.Keywords: lumber spine, internal fixation device, finite element method, biomechanics
Procedia PDF Downloads 3811530 Islamic Banks and the Most Important Contemporary Challenges
Authors: Mahmood Mohammed Abdulsattar Aljumaili
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Praise be to Allah and peace and blessings be upon the Messenger of Allah. Islamic banks have not only made a lot of great achievements in a short period, but they imposed themselves in the global market, not to mention the transformation of some conventional interest-based banks to Islamic banks to the large demand on them, this transformation has pushed the Dow Jones Global Foundation to develop a new economic indicator released it (the Dow Jones Islamic market) for those who wish to invest in Islamic financial institutions. The success of Islamic financial institutions today face significant and serious challenges, that embody the serious consequences created by the current events on Islamic banking industry. This modest study, deals with these serious challenges facing the Islamic banking industry, and reflected on the success recorded in the previous period. The study deals with four main topics: The emergence of Islamic banks, the goals of Islamic banks, International challenges facing Islamic banks, internal challenges facing Islamic banks, and finally it touches on, (Basel 1-2) Agreement and its implications for Islamic banks.Keywords: Islamic banks, Basel 1-2 agreement, most important contemporary challenges, islamic banking industry, Dow Jones Islamic market
Procedia PDF Downloads 5031529 Corrosion Characteristics and Electrochemical Treatment of Heritage Silver Alloys
Authors: Ahmad N. Abu-Baker
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This study investigated the corrosion of a group of heritage silver-copper alloy coins and their conservation treatment by potentiostatic methods. The corrosion products of the coins were characterized by a combination of scanning electron microscopy/ energy-dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD) analyses. Cathodic polarization curves, measured by linear sweep voltammetry (LSV), also identified the corrosion products and the working conditions to treat the coins using a potentiostatic reduction method, which was monitored by chronoamperometry. The corrosion products showed that the decay mechanisms were dominated by selective attack on the copper-rich phases of the silver-copper alloys, which is consistent with an internal galvanic corrosion phenomenon, which leads to the deposition of copper corrosion products on the surface of the coins. Silver chloride was also detected on the coins, which reflects selective corrosion of the silver-rich phases under different chemical environments. The potentiostatic treatment showed excellent effectiveness in determining treatment parameters and monitoring the reduction process of the corrosion products on the coins, which helped to preserve surface details in the cleaning process and to prevent over-treatment.Keywords: silver alloys, corrosion, conservation, heritage
Procedia PDF Downloads 1441528 China's Middle East Policy and the Competition with the United States
Authors: Shabnam Dadparvar, Laijin Shen
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This paper focuses on China’s policy in the Middle East and the rivalry with the U.S. The question is that what are the main factors on China’s Middle East policy and its competition with the U.S? The hypothesis regards to three effective factors: 'China’s energy dependency' on the Middle East, 'economy' and support for 'stability' in the Middle East. What is important in China’s competition with the U.S regarding to its Middle East policy is the substantial difference in ways of treating the countries of the region; China is committed to Westphalia model based on non-interference in internal affairs of the countries and respect the sovereignty of the governments. However, after 9/11, the U.S is seeking a balance between stability and change through intervention in the international affairs and in some cases is looking for a regime change. From the other hand, China, due to its dependency on the region’s energy welcomes America’s military presence in the region for providing stability. The authors by using a descriptive analytical method try to explain the situation of rivalry between China and the United States in Middle East. China is an 'emerging power' with high economic growth and in demand of more energy supply. The problem is that a rising power in the region is often a source of concern for hegemony.Keywords: China's foreign policy, energy, hegemony, the Middle East
Procedia PDF Downloads 3551527 Developing and Testing a Questionnaire of Music Memorization and Practice
Authors: Diana Santiago, Tania Lisboa, Sophie Lee, Alexander P. Demos, Monica C. S. Vasconcelos
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Memorization has long been recognized as an arduous and anxiety-evoking task for musicians, and yet, it is an essential aspect of performance. Research shows that musicians are often not taught how to memorize. While memorization and practice strategies of professionals have been studied, little research has been done to examine how student musicians learn to practice and memorize music in different cultural settings. We present the process of developing and testing a questionnaire of music memorization and musical practice for student musicians in the UK and Brazil. A survey was developed for a cross-cultural research project aiming at examining how young orchestral musicians (aged 7–18 years) in different learning environments and cultures engage in instrumental practice and memorization. The questionnaire development included members of a UK/US/Brazil research team of music educators and performance science researchers. A pool of items was developed for each aspect of practice and memorization identified, based on literature, personal experiences, and adapted from existing questionnaires. Item development took the varying levels of cognitive and social development of the target populations into consideration. It also considered the diverse target learning environments. Items were initially grouped in accordance with a single underlying construct/behavior. The questionnaire comprised three sections: a demographics section, a section on practice (containing 29 items), and a section on memorization (containing 40 items). Next, the response process was considered and a 5-point Likert scale ranging from ‘always’ to ‘never’ with a verbal label and an image assigned to each response option was selected, following effective questionnaire design for children and youths. Finally, a pilot study was conducted with young orchestral musicians from diverse learning environments in Brazil and the United Kingdom. Data collection took place in either one-to-one or group settings to facilitate the participants. Cognitive interviews were utilized to establish response process validity by confirming the readability and accurate comprehension of the questionnaire items or highlighting the need for item revision. Internal reliability was investigated by measuring the consistency of the item groups using the statistical test Cronbach’s alpha. The pilot study successfully relied on the questionnaire to generate data about the engagement of young musicians of different levels and instruments, across different learning and cultural environments, in instrumental practice and memorization. Interaction analysis of the cognitive interviews undertaken with these participants, however, exposed the fact that certain items, and the response scale, could be interpreted in multiple ways. The questionnaire text was, therefore, revised accordingly. The low Cronbach’s Alpha scores of many item groups indicated another issue with the original questionnaire: its low level of internal reliability. Several reasons for each poor reliability can be suggested, including the issues with item interpretation revealed through interaction analysis of the cognitive interviews, the small number of participants (34), and the elusive nature of the construct in question. The revised questionnaire measures 78 specific behaviors or opinions. It can be seen to provide an efficient means of gathering information about the engagement of young musicians in practice and memorization on a large scale.Keywords: cross-cultural, memorization, practice, questionnaire, young musicians
Procedia PDF Downloads 1241526 Experimental Study of Complete Loss of Coolant Flow (CLOF) Test by System–Integrated Modular Advanced Reactor Integral Test Loop (SMART-ITL) with Passive Residual Heat Removal System (PRHRS)
Authors: Jin Hwa Yang, Hwang Bae, Sung Uk Ryu, Byong Guk Jeon, Sung Jae Yi, Hyun Sik Park
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Experimental studies using a large-scale thermal-hydraulic integral test facility, System–integrated Modular Advanced Reactor Integral Test Loop (SMART-ITL), have been carried out to validate the performance of the prototype, SMART. After Fukushima accident, the passive safety systems have been dealt as important designs for retaining of nuclear safety. One of the concerned scenarios for evaluating the passive safety system is a Complete Loss of Coolant Flow (CLOF). The flowrate of coolant in the primary system is maintained by Reactor Coolant Pump (RCP). When the supply of electric power of RCP is shut off, the flowrate of coolant decreases sharply, and the temperature of the coolant increases rapidly. Therefore, the reactor trip signal is activated to prevent the over-heating of the core. In this situation, Passive Residual Heat Removal System (PRHRS) plays a significant role to assure the soundness of the SMART. The PRHRS using a two-phase natural circulation is a passive safety system in the SMART to eliminate the heat of steam generator in the secondary system with heat exchanger submarined in the Emergency Cooling Tank (ECT). As the RCPs continue to coast down, inherent natural circulation in the primary system transfers heat to the secondary system. The transferred heat is removed by PRHRS in the secondary system. In this paper, the progress of the CLOF accident is described with experimental data of transient condition performed by SMART-ITL. Finally, the capability of passive safety system and inherent natural circulation will be evaluated.Keywords: CLOF, natural circulation, PRHRS, SMART-ITL
Procedia PDF Downloads 4431525 Conjugate Heat Transfer Analysis of a Combustion Chamber using ANSYS Computational Fluid Dynamics to Estimate the Thermocouple Positioning in a Chamber Wall
Authors: Muzna Tariq, Ihtzaz Qamar
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In most engineering cases, the working temperatures inside a combustion chamber are high enough that they lie beyond the operational range of thermocouples. Furthermore, design and manufacturing limitations restrict the use of internal thermocouples in many applications. Heat transfer inside a combustion chamber is caused due to interaction of the post-combustion hot fluid with the chamber wall. Heat transfer that involves an interaction between the fluid and solid is categorized as Conjugate Heat Transfer (CHT). Therefore, to satisfy the needs of CHT, CHT Analysis is performed by using ANSYS CFD tool to estimate theoretically precise thermocouple positions at the combustion chamber wall where excessive temperatures (beyond thermocouple range) can be avoided. In accordance with these Computational Fluid Dynamics (CFD) results, a combustion chamber is designed, and a prototype is manufactured with multiple thermocouple ports positioned at the specified distances so that the temperature of hot gases can be measured on the chamber wall where the temperatures do not exceed the thermocouple working range.Keywords: computational fluid dynamics, conduction, conjugate heat transfer, convection, fluid flow, thermocouples
Procedia PDF Downloads 1521524 Influence of an External Magnetic Field on the Acoustomagnetoelectric Field in a Rectangular Quantum Wire with an Infinite Potential by Using a Quantum Kinetic Equation
Authors: N. Q. Bau, N. V. Nghia
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The acoustomagnetoelectric (AME) field in a rectangular quantum wire with an infinite potential (RQWIP) is calculated in the presence of an external magnetic field (EMF) by using the quantum kinetic equation for the distribution function of electrons system interacting with external phonons and electrons scattering with internal acoustic phonon in a RQWIP. We obtained ananalytic expression for the AME field in the RQWIP in the presence of the EMF. The dependence of AME field on the frequency of external acoustic wave, the temperature T of system, the cyclotron frequency of the EMF and the intensity of the EMF is obtained. Theoretical results for the AME field are numerically evaluated, plotted and discussed for a specific RQWIP GaAs/GaAsAl. This result has shown that the dependence of the AME field on intensity of the EMF is nonlinearly and it is many distinct maxima in the quantized magnetic region. We also compared received fields with those for normal bulk semiconductors, quantum well and quantum wire to show the difference. The influence of an EMF on AME field in a RQWIP is newly developed.Keywords: rectangular quantum wire, acoustomagnetoelectric field, electron-phonon interaction, kinetic equation method
Procedia PDF Downloads 3381523 Presenting a Model for Predicting the State of Being Accident-Prone of Passages According to Neural Network and Spatial Data Analysis
Authors: Hamd Rezaeifar, Hamid Reza Sahriari
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Accidents are considered to be one of the challenges of modern life. Due to the fact that the victims of this problem and also internal transportations are getting increased day by day in Iran, studying effective factors of accidents and identifying suitable models and parameters about this issue are absolutely essential. The main purpose of this research has been studying the factors and spatial data affecting accidents of Mashhad during 2007- 2008. In this paper it has been attempted to – through matching spatial layers on each other and finally by elaborating them with the place of accident – at the first step by adding landmarks of the accident and through adding especial fields regarding the existence or non-existence of effective phenomenon on accident, existing information banks of the accidents be completed and in the next step by means of data mining tools and analyzing by neural network, the relationship between these data be evaluated and a logical model be designed for predicting accident-prone spots with minimum error. The model of this article has a very accurate prediction in low-accident spots; yet it has more errors in accident-prone regions due to lack of primary data.Keywords: accident, data mining, neural network, GIS
Procedia PDF Downloads 511522 A Functional Thermochemical Energy Storage System for Mobile Applications: Design and Performance Analysis
Authors: Jure Galović, Peter Hofmann
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Thermochemical energy storage (TCES), as a long-term and lossless energy storage principle, provides a contribution for the reduction of greenhouse emissions of mobile applications, such as passenger vehicles with an internal combustion engine. A prototype of a TCES system, based on reversible sorption reactions of LiBr composite and methanol has been designed at Vienna University of Technology. In this paper, the selection of reactive and inert carrier materials as well as the design of heat exchangers (reactor vessel and evapo-condenser) was reviewed and the cycle stability under real operating conditions was investigated. The performance of the developed system strongly depends on the environmental temperatures, to which the reactor vessel and evapo-condenser are exposed during the phases of thermal conversion. For an integration of the system into mobile applications, the functionality of the designed prototype was proved in numerous conducted cycles whereby no adverse reactions were observed.Keywords: dynamic applications, LiBr composite, methanol, performance of TCES system, sorption process, thermochemical energy storage
Procedia PDF Downloads 1681521 Economic Forecasting Analysis for Solar Photovoltaic Application
Authors: Enas R. Shouman
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Economic development with population growth is leading to a continuous increase in energy demand. At the same time, growing global concern for the environment is driving to decrease the use of conventional energy sources and to increase the use of renewable energy sources. The objective of this study is to present the market trends of solar energy photovoltaic technology over the world and to represent economics methods for PV financial analyzes on the basis of expectations for the expansion of PV in many applications. In the course of this study, detailed information about the current PV market was gathered and analyzed to find factors influencing the penetration of PV energy. The paper methodology depended on five relevant economic financial analysis methods that are often used for investment decisions maker. These methods are payback analysis, net benefit analysis, saving-to-investment ratio, adjusted internal rate of return, and life-cycle cost. The results of this study may be considered as a marketing guide that helps diffusion of using PV Energy. The study showed that PV cost is economically reliable. The consumers will pay higher purchase prices for PV system installation but will get lower electricity bill.Keywords: photovoltaic, financial methods, solar energy, economics, PV panel
Procedia PDF Downloads 1121520 Multi-Faceted Growth in Creative Industries
Authors: Sanja Pfeifer, Nataša Šarlija, Marina Jeger, Ana Bilandžić
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The purpose of this study is to explore the different facets of growth among micro, small and medium-sized firms in Croatia and to analyze the differences between models designed for all micro, small and medium-sized firms and those in creative industries. Three growth prediction models were designed and tested using the growth of sales, employment and assets of the company as dependent variables. The key drivers of sales growth are: prudent use of cash, industry affiliation and higher share of intangible assets. Growth of assets depends on retained profits, internal and external sources of financing, as well as industry affiliation. Growth in employment is closely related to sources of financing, in particular, debt and it occurs less frequently than growth in sales and assets. The findings confirm the assumption that growth strategies of small and medium-sized enterprises (SMEs) in creative industries have specific differences in comparison to SMEs in general. Interestingly, only 2.2% of growing enterprises achieve growth in employment, assets and sales simultaneously.Keywords: creative industries, growth prediction model, growth determinants, growth measures
Procedia PDF Downloads 3331519 The Analysis of Brain Response to Auditory Stimuli through EEG Signals’ Non-Linear Analysis
Authors: H. Namazi, H. T. N. Kuan
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Brain activity can be measured by acquiring and analyzing EEG signals from an individual. In fact, the human brain response to external and internal stimuli is mapped in his EEG signals. During years some methods such as Fourier transform, wavelet transform, empirical mode decomposition, etc. have been used to analyze the EEG signals in order to find the effect of stimuli, especially external stimuli. But each of these methods has some weak points in analysis of EEG signals. For instance, Fourier transform and wavelet transform methods are linear signal analysis methods which are not good to be used for analysis of EEG signals as nonlinear signals. In this research we analyze the brain response to auditory stimuli by extracting information in the form of various measures from EEG signals using a software developed by our research group. The used measures are Jeffrey’s measure, Fractal dimension and Hurst exponent. The results of these analyses are useful not only for fundamental understanding of brain response to auditory stimuli but provide us with very good recommendations for clinical purposes.Keywords: auditory stimuli, brain response, EEG signal, fractal dimension, hurst exponent, Jeffrey’s measure
Procedia PDF Downloads 535