Search results for: electrical performance
13448 Sustainability Performance in the Post-Pandemic Era: Employee Resilience Impact on Improving Employee and Organizational Performance
Authors: Sonali Mohite
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Severe changes to Organizational Sustainability (OS) have been brought about by the COVID-19 pandemic. This situation forces organizations to tackle the competencies required to augment Employee Resilience (ER) and make profitable growth. This study explores how employee resilience contributes to both individual and organizational success in the wake of the COVID-19 pandemic. We suggest that employees who possess strong coping mechanisms and adaptability are better equipped to handle ongoing disruptions, resulting in improved individual performance metrics like productivity, engagement, and innovative thinking. Hence, exploring the efficiency of ER in improving EP and OS in post-pandemic (PP) is the aim of this research. By utilizing convenience sampling techniques, a total of 422 employees have been collected from numerous organizations. After that, the study’s hypothesis is analysed by using Structural Equation Modelling (SEM). As per the study’s findings, the ER factors of “Job Satisfaction (JS)”, “Self-Efficacy (SE)”, “Supervisors’ Support (SS)”, and “Facilitating Conditions (FC)” have positive and significant associations with organizational efficiency. Furthermore, the study’s findings also exhibited that there is the most important relation between SE and EOP.Keywords: employee resilience, employee performance, organizational performance, sustainability, post-pandemic
Procedia PDF Downloads 2213447 Dynamic Communications Mapping in NoC-Based Heterogeneous MPSoCs
Authors: M. K. Benhaoua, A. K. Singh, A. E. H. Benyamina
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In this paper, we propose heuristic for dynamic communications mapping that considers the placement of communications in order to optimize the overall performance. The mapping technique uses a newly proposed Algorithm to place communications between the tasks. The placement we propose of the communications leads to a better optimization of several performance metrics (time and energy consumption). Experimental results show that the proposed mapping approach provides significant performance improvements when compared to those using static routing.Keywords: Multi-Processor Systems-on-Chip (MPSoCs), Network-on-Chip (NoC), heterogeneous architectures, dynamic mapping heuristics
Procedia PDF Downloads 53313446 Effects of Internet Addiction on Students’ Academic Performance among Some Tertiary Institutions in Oyo State, Nigeria
Authors: Mujidat Lola Olugbode
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This study investigates the effects of internet addiction on academic performance among students in some tertiary institutions in Oyo State, Nigeria. A descriptive survey research design was adopted for the study. Two research questions and two hypotheses were answered and tested. The population of the study comprised of all students in five tertiary institutions in Oyo State, Nigeria. Simple random sampling technique was used to select 2550 participants (respondents) from the institutions used for the study, this constituted the sample for the study. The instruments used for data collection was a self-constructed questionnaire on Internet Addiction and Students Academic Performance (IAASAP). The reliability coefficient of the instrument was 0.77. Data collected were analyzed using frequency and percentages, Pearson Product Moment Correlation coefficient (PPMCC) and t-test analysis. The results showed that the students in tertiary institutions in Oyo State were occasionally addicted to internet use. The study also revealed a positive correlation between internet addiction and academic performance. The findings also showed that there was significant difference in the internet addiction between male and female Students. Based on the above findings, the researchers recommended among others that government, educators, parents, counselors, teachers should help redirect the internet use toward academics to ensure greater academic performance.Keywords: internet, addiction, internet addiction, academic performance, tertiary institution, students
Procedia PDF Downloads 6413445 Preparation of 3D Graphene with Microwave-Hydrothermal Assistance for Ultrahigh Performance of Capacitive Deionization
Authors: Wahid Dianbudiyanto, Shou Heng Liu
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Capacitive deionization (CDI) is a prospective desalination technology, which can be operated at low voltage, low temperature and potentially consume low energy for brackish water desalination. To obtain the optimal electrosorption, an electrode should possess high electrical conductivity, large surface area, good wettability, highly mesoporous structure which provide efficient pathways for ion distribution. In this work, a 3D structure graphene was fabricated using hydrothermal method which is assisted with microwave treatments to form 3D rGO (3DG-Mw-Hyd). The prepared samples have excellent specific capacitance (189.2 F / g) and ultrahigh electrosorption capacity (30 mg/g) for the desalination of 500 mg / l NaCl. These results are superior to the electrode which is fabricated only using the hydrothermal method without microwave assistance (3DG-Hyd) and traditional reflux method. Physical characterizations such as SEM, TEM, and XRD have been used to study the property difference of the materials. The preliminary results show that 3DG-Mw-Hyd is one of the promising electrodes for CDI in the practical applications.Keywords: capacitive deionization, graphene, microwave, hydrothermal, electrosorption
Procedia PDF Downloads 29413444 Impact of Strategic Leadership on Corporate Performance
Authors: Adesina Nathaniel Olanrewaju
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The motivation behind this study is the need to see strategic leadership as one of the key driving forces for improving corporate performance. Strategic leadership is seen as a potent source of management development and sustained competitive advantage for both employee and organizational performance. There is currently a charge on leaders as a major cause of organizational failure. Stakeholders give what they can afford, not necessarily what the organization needs and impose operational and financial decisions on the leaders, 200 respondents were fit for the analysis from the six geo-political regions in Nigeria. The selection was done equally among various parastatals through random sampling technique from the south-south, south-east, south-west, north-east, north-west and north-central. A descriptive research of the survey was employed. The data were subjected to t-test analysis and correlation and regression were used for the analysis. The findings revealed that there is a strong relationship and impact between a strategic leader and corporate performance. Recommendations were made based on the findings that strategic leaders should be given the blueprint, company’s policy and the stakeholders’ expectation within a time frame the work is to be carried out.Keywords: time, strategic, organization, stakeholder, leader, performance
Procedia PDF Downloads 30513443 Effects of Practical Activities on Performance among Biology Students in Zaria Education Zone, Kaduna State Nigeria
Authors: Abdullahi Garba
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The study investigated the effects of practical activities on performance among biology students in Zaria education zone, Kaduna State, Nigeria. The population consists of 18 public schools in the Zaria Education Zone with a total number of 4,763 students. A random sample of 115 students was selected from the population in the study area. The study design was quasi-experimental, which adopted the pre-test, post-test experimental, and control group design. The experimental group was exposed to practical activities, while the control group was taught with the lecture method. A validated instrument, a biology performance test (BPT) with a reliability coefficient of 0.82, was used to gather data which were analyzed using a t-test and paired sample t-test. Two research questions and hypotheses guided the study. The hypotheses were tested at p≤0.05 level of significance. Findings revealed that: there was a significant difference in the academic performance of students exposed to practical activities compared to their counterparts; there was no significant difference in performance between male and female Biology students exposed to practical activities. The recommendation given was that practical activities should be encouraged in the teaching and learning of Biology for better understanding. The Federal and State Ministry of Education should sponsor biology teachers for training and retraining of teachers to improve the academic performance of students in the subject.Keywords: biology, practical, activity, performance
Procedia PDF Downloads 8013442 Experimental, Computational Fluid Dynamics and Theoretical Study of Cyclone Performance Based on Inlet Velocity and Particle Loading Rate
Authors: Sakura Ganegama Bogodage, Andrew Yee Tat Leung
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This paper describes experimental, Computational Fluid Dynamics (CFD) and theoretical analysis of a cyclone performance, operated 1.0 g/m3 solid loading rate, at two different inlet velocities (5 m/s and 10 m/s). Comparing experimental results with theoretical and CFD simulation results, it is pronounced that the influence of solid in processing flow is significant than expected. Experimental studies based on gas- solid flows of cyclone separators are complicated as they required advanced sensitive measuring techniques, especially flow characteristics. Thus, CFD modelling and theoretical analysis are economical in analyzing cyclone separator performance but detailed clarifications of the application of these in cyclone separator performance evaluation is not yet discussed. The present study shows the limitations of influencing parameters of CFD and theoretical considerations, comparing experimental results and flow characteristics from CFD modelling.Keywords: cyclone performance, inlet velocity, pressure drop, solid loading rate
Procedia PDF Downloads 23713441 Numerical Investigation of a Supersonic Ejector for Refrigeration System
Authors: Karima Megdouli, Bourhan Taschtouch
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Supersonic ejectors have many applications in refrigeration systems. And improving ejector performance is the key to improve the efficiency of these systems. One of the main advantages of the ejector is its geometric simplicity and the absence of moving parts. This paper presents a theoretical model for evaluating the performance of a new supersonic ejector configuration for refrigeration system applications. The relationship between the flow field and the key parameters of the new configuration has been illustrated by analyzing the Mach number and flow velocity contours. The method of characteristics (MOC) is used to design the supersonic nozzle of the ejector. The results obtained are compared with those obtained by CFD. The ejector is optimized by minimizing exergy destruction due to irreversibility and shock waves. The optimization converges to an efficient optimum solution, ensuring improved and stable performance over the whole considered range of uncertain operating conditions.Keywords: supersonic ejector, theoretical model, CFD, optimization, performance
Procedia PDF Downloads 7613440 Transformational Leadership and Departmental Performance: The Intervening Role of Internal Communication and Citizen/Customer Participation
Authors: Derrick Boakye Boadu, Zahra Fakhri
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Transformational leaders are the catalyst of change and focus more importantly on members or followers. Involvement of transformational leadership style in organizational structures can provide interesting nuances to the implementation and enhancement of citizen and customer participation mechanisms in an organization regardless of the time consuming, cost, and delaying process of analyzing the feedback of workers and citizens/customers which stifles good outcome of organization’s department performance. It posits that transformational leadership has a positive direct effect on organization-departmental performance and the intervening role of citizen and customer participation and internal communication. Using the NASP-IV 2007 data, the article finds support for the five hypotheses in a structural equation model, and the findings show that transformational leadership does have a direct impact on organizational-departmental performance a partial mediation effect of the relationship through the role of internal communication and citizen and customer participation.Keywords: transformational leaders, departmental performance, internal communication, citizen/customer participation
Procedia PDF Downloads 11713439 Performance of Staggered Wall Buildings Subjected to Low to Medium Earthquake Loads
Authors: Younghoo Choi, Yong Jun, Jinkoo Kim
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In this study seismic performance of typical reinforced concrete staggered wall system structures was evaluated through nonlinear static and incremental dynamic analyses. To this end, and 15-story SWS structures were designed and were analyzed to obtain their nonlinear force-displacement relationships. The analysis results showed that the 5-story SWS structures failed due to yielding of columns and walls located in the lower stories, whereas in the 15-story structures plastic hinges were more widely distributed throughout the stories.Keywords: staggered wall systems, reinforced concrete, seismic performance
Procedia PDF Downloads 39213438 Performance Assessment of GSO Satellites before and after Enhancing the Pointing Effect
Authors: Amr Emam, Joseph Victor, Mohamed Abd Elghany
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The paper presents the effect of the orbit inclination on the pointing error of the satellite antenna and consequently on its footprint on earth for a typical Ku- band payload system. The performance assessment is examined both theoretically and by means of practical measurements, taking also into account all additional sources of pointing errors, such as East-West station keeping, orbit eccentricity and actual attitude control performance. An implementation and computation of the sinusoidal biases in satellite roll and pitch used to compensate the pointing error of the satellite antenna coverage is studied and evaluated before and after the pointing corrections performed. A method for evaluation of the performance of the implemented biases has been introduced through measuring satellite received level from a tracking 11m and fixed 4.8m transmitting antenna before and after the implementation of the pointing corrections.Keywords: satellite, inclined orbit, pointing errors, coverage optimization
Procedia PDF Downloads 40313437 Mechanical Properties and Microstructure of Ultra-High Performance Concrete Containing Fly Ash and Silica Fume
Authors: Jisong Zhang, Yinghua Zhao
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The present study investigated the mechanical properties and microstructure of Ultra-High Performance Concrete (UHPC) containing supplementary cementitious materials (SCMs), such as fly ash (FA) and silica fume (SF), and to verify the synergistic effect in the ternary system. On the basis of 30% fly ash replacement, the incorporation of either 10% SF or 20% SF show a better performance compared to the reference sample. The efficiency factor (k-value) was calculated as a synergistic effect to predict the compressive strength of UHPC with these SCMs. The SEM of micrographs and pore volume from BJH method indicate a high correlation with compressive strength. Further, an artificial neural networks model was constructed for prediction of the compressive strength of UHPC containing these SCMs.Keywords: artificial neural network, fly ash, mechanical properties, ultra-high performance concrete
Procedia PDF Downloads 41413436 A Review on Electrical Behavior of Different Substrates, Electrodes and Membranes in Microbial Fuel Cell
Authors: Bharat Mishra, Sanjay Kumar Awasthi, Raj Kumar Rajak
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The devices, which convert the energy in the form of electricity from organic matters, are called microbial fuel cell (MFC). Recently, MFCs have been given a lot of attention due to their mild operating conditions, and various types of biodegradable substrates have been used in the form of fuel. Traditional MFCs were included in anode and cathode chambers, but there are single chamber MFCs. Microorganisms actively catabolize substrate, and bioelectricities are produced. In the field of power generation from non-conventional sources, apart from the benefits of this technique, it is still facing practical constraints such as low potential and power. In this study, most suitable, natural, low cost MFCs components are electrodes (anode and cathode), organic substrates, membranes and its design is selected on the basis of maximum potential (voltage) as an electrical parameter, which indicates a vital role of affecting factor in MFC for sustainable power production.Keywords: substrates, electrodes, membranes, MFCs design, voltage
Procedia PDF Downloads 30613435 Potential Applications and Future Prospects of Zinc Oxide Thin Films
Authors: Temesgen Geremew
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ZnO is currently receiving a lot of attention in the semiconductor industry due to its unique characteristics. ZnO is widely used in solar cells, heat-reflecting glasses, optoelectronic bias, and detectors. In this composition, we provide an overview of the ZnO thin flicks' packages, methods of characterization, and implicit operations. They consist of Transmission spectroscopy, Raman spectroscopy, Field emigration surveying electron microscopy, and X-ray diffraction. This review content also demonstrates how ZnO thin flicks function in electrical components for piezoelectric bias, optoelectronics, detectors, and renewable energy sources. Zinc oxide (ZnO) thin films offer a captivating tapestry of possibilities due to their unique blend of electrical, optical, and mechanical properties. This review delves into the realm of their potential applications and future prospects, highlighting the pivotal contributions of research endeavors aimed at tailoring their functionalities.Keywords: Zinc oxide, raman spectroscopy, thin films, piezoelectric devices
Procedia PDF Downloads 8413434 Musical Tesla Coil with Faraday Box Controlled by a GNU Radio
Authors: Jairo Vega, Fabian Chamba, Jordy Urgiles
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In this work, the implementation of a Matlabcontrolled Musical Tesla Coil and external audio signals was presented. First, the audio signal was obtained from a mobile device and processed in Matlab to modify it, adding noise or other desired effects. Then, the processed signal was passed through a preamplifier to increase its amplitude to a level suitable for further amplification through a power amplifier, which was part of the current driver circuit of the Tesla coil. To get the Tesla coil to generate music, a circuit capable of modulating and generating the audio signal by manipulating electrical discharges was used. To visualize and listen to these discharges, a small Faraday cage was built to attenuate the external electric fields. Finally, the implementation of the musical Tesla coil was concluded. However, it was observed that the audio signal volume was very low, and the components used heated up quickly. Due to these limitations, it was determined that the project could not be connected to power for long periods of time.Keywords: Tesla coil, plasma, electrical signals, GNU Radio
Procedia PDF Downloads 9713433 Mechanical Properties and Microstructural Analyzes of Epoxy Resins Reinforced with Satin Tissue
Authors: Băilă Diana Irinel, Păcurar Răzvan, Păcurar Ancuța
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Although the volumes of fibre reinforced polymer composites (FRPs) used for aircraft applications is a relatively small percentage of total use, the materials often find their most sophisticated applications in this industry. In aerospace, the performance criteria placed upon materials can be far greater than in other areas – key aspects are light-weight, high-strength, high-stiffness, and good fatigue resistance. Composites were first used by the military before the technology was applied to commercial planes. Nowadays, composites are widely used, and this has been the result of a gradual direct substitution of metal components followed by the development of integrated composite designs as confidence in FRPs has increased. The airplane uses a range of components made from composites, including the fin and tailplane. In the last years, composite materials are increasingly used in automotive applications due to the improvement of material properties. In the aerospace and automotive sector, the fuel consumption is proportional to the weight of the body of the vehicle. A minimum of 20% of the cost can be saved if it used polymer composites in place of the metal structures and the operating and maintenance costs are alco very low. Glass fiber-epoxy composites are widely used in the making of aircraft and automobile body parts and are not only limited to these fields but also used in ship building, structural applications in civil engineering, pipes for the transport of liquids, electrical insulators in reactors. This article was establish the high-performance of composite material, a type glass-epoxy used in automotive and aeronautic domains, concerning the tensile and flexural tests and SEM analyzes.Keywords: glass-epoxy composite, traction and flexion tests, SEM analysis, acoustic emission (AE) signals
Procedia PDF Downloads 10313432 Performance Validation of Model Predictive Control for Electrical Power Converters of a Grid Integrated Oscillating Water Column
Authors: G. Rajapakse, S. Jayasinghe, A. Fleming
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This paper aims to experimentally validate the control strategy used for electrical power converters in grid integrated oscillating water column (OWC) wave energy converter (WEC). The particular OWC’s unidirectional air turbine-generator output power results in discrete large power pulses. Therefore, the system requires power conditioning prior to integrating to the grid. This is achieved by using a back to back power converter with an energy storage system. A Li-Ion battery energy storage is connected to the dc-link of the back-to-back converter using a bidirectional dc-dc converter. This arrangement decouples the system dynamics and mitigates the mismatch between supply and demand powers. All three electrical power converters used in the arrangement are controlled using finite control set-model predictive control (FCS-MPC) strategy. The rectifier controller is to regulate the speed of the turbine at a set rotational speed to uphold the air turbine at a desirable speed range under varying wave conditions. The inverter controller is to maintain the output power to the grid adhering to grid codes. The dc-dc bidirectional converter controller is to set the dc-link voltage at its reference value. The software modeling of the OWC system and FCS-MPC is carried out in the MATLAB/Simulink software using actual data and parameters obtained from a prototype unidirectional air-turbine OWC developed at Australian Maritime College (AMC). The hardware development and experimental validations are being carried out at AMC Electronic laboratory. The designed FCS-MPC for the power converters are separately coded in Code Composer Studio V8 and downloaded into separate Texas Instrument’s TIVA C Series EK-TM4C123GXL Launchpad Evaluation Boards with TM4C123GH6PMI microcontrollers (real-time control processors). Each microcontroller is used to drive 2kW 3-phase STEVAL-IHM028V2 evaluation board with an intelligent power module (STGIPS20C60). The power module consists of a 3-phase inverter bridge with 600V insulated gate bipolar transistors. Delta standard (ASDA-B2 series) servo drive/motor coupled to a 2kW permanent magnet synchronous generator is served as the turbine-generator. This lab-scale setup is used to obtain experimental results. The validation of the FCS-MPC is done by comparing these experimental results to the results obtained by MATLAB/Simulink software results in similar scenarios. The results show that under the proposed control scheme, the regulated variables follow their references accurately. This research confirms that FCS-MPC fits well into the power converter control of the OWC-WEC system with a Li-Ion battery energy storage.Keywords: dc-dc bidirectional converter, finite control set-model predictive control, Li-ion battery energy storage, oscillating water column, wave energy converter
Procedia PDF Downloads 11313431 A Performance Model for Designing Network in Reverse Logistic
Authors: S. Dhib, S. A. Addouche, T. Loukil, A. Elmhamedi
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In this paper, a reverse supply chain network is investigated for a decision making. This decision is surrounded by complex flows of returned products, due to the increasing quantity, the type of returned products and the variety of recovery option products (reuse, recycling, and refurbishment). The most important problem in the reverse logistic network (RLN) is to orient returned products to the suitable type of recovery option. However, returned products orientations from collect sources to the recovery disposition have not well considered in performance model. In this study, we propose a performance model for designing a network configuration on reverse logistics. Conceptual and analytical models are developed with taking into account operational, economic and environmental factors on designing network.Keywords: reverse logistics, network design, performance model, open loop configuration
Procedia PDF Downloads 43513430 Functional Electrical Stimulator and Neuromuscular Electro Stimulator System Analysis for Foot Drop
Authors: Gül Fatma Türker, Hatice Akman
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Portable muscle stimulators for real-time applications has first introduced by Liberson in 1961. Now these systems has been advanced. In this study, FES (Functional Electrical Stimulator) and NMES (Neuromuscular Electrostimulator) systems are analyzed through their hardware and their quality of life improvements for foot drop patients. FES and NMES systems are used for people whose leg muscles and leg neural connections are healty but not able to walk properly because of their injured central nervous system like spinal cord injuries. These systems are used to stimulate neurons or muscles by getting information from other movements and programming these stimulations to get natural walk and it is accepted as a rehabilitation method for the correction of drop foot. This systems support person to approach natural form of walking. Foot drop is characterized by steppage gait. It is a gait abnormality. This systems helps to person for plantar and dorse reflection movements which are hard to done for foot drop patients.Keywords: FES, foot drop, NMES, stimulator
Procedia PDF Downloads 38813429 Aphasia, Silence and the Non-Verbalisation of Performance (in Music)
Authors: Navonil Hazra
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The paper discusses how and why aphasia can be understood as the language of nonverbal communication in musical performance and also looks for the elements that are required to classify it as a nonverbal language. Since music is regarded as a nonverbal medium that cannot be engaged in any language, it is concerned about how aphasia might be called the language of nonverbalization. The paper also talks about how it portrays the magnificence of a performance, and how it expresses its likings or dislikes. Regarding the reasons for aphasia, the paper talks about the seizure factor and elucidates on seizure subjects as well. Furthermore, it discusses collective seizures and individual seizures. It also tries to consider aphasia as a-posteriori rather than a-priori looking at it from the lens of ‘Pure Reason’. Along with aphasia, the paper tries to make a critique of silence and the possibilities of looking at silence differently, also looking at the ontology of silence and sound. This paper also critically examines silence and the significance of gestures in performance. It also investigates whether gestures are accompanied by silence, establishing the notion of agential silence. This paper also talks about the place and role of memory in the formulation and analysis of a performance, as well as the plaguing and reclamation of memory, how memory alters the linear course of time and taunts us to look for alternative models of temporalities. This paper discusses the concept of 'auditory labour', with active and passive listening.Keywords: aphasia, gestures, memory, silence
Procedia PDF Downloads 4313428 The Value of Dynamic Magnetic Resonance Defecography in Assessing the Severity of Defecation Disorders
Authors: Ge Sun, Monika Trzpis, Robbert J. de Haas, Paul M. A. Broens
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Introduction: Dynamic magnetic resonance defecography is frequently used to assess defecation disorders. We aimed to investigate the usefulness of dynamic magnetic resonance defecography for assessing the severity of defecation disorder. Methods: We included patients retrospectively from our tertiary referral hospital who had undergone dynamic magnetic resonance defecography, anorectal manometry, and anal electrical sensitivity tests to assess defecation disorders between 2014 and 2020. The primary outcome was the association between the dynamic magnetic resonance defecography variables and the severity of defecation disorders. We assessed the severity of fecal incontinence and constipation with the Wexner incontinence and Agachan constipation scores. Results: Out of the 32 patients included, 24 completed the defecation questionnaire. During defecation, the M line length at magnetic resonance correlated with the Agachan score (r = 0.45, p = 0.03) and was associated with anal sphincter pressure (r=0.39, p=0.03) just before defecation. During rest and squeezing, the H line length at imaging correlated with the Wexner incontinence score (r=0.49, p=0.01 and r=0.69, p< 0.001, respectively). H line length also correlated positively with the anal electrical sensation threshold during squeezing (r=0.50, p=0.004) and during rest (r= 0.42, p=0.02). Conclusions: The M and H line lengths at dynamic magnetic resonance defecography can be used to assess the severity of constipation and fecal incontinence respectively and reflect anatomic changes of the pelvic floor. However, as these anatomic changes are generally late-stage and irreversible, anal manometry seems a better diagnostic approach to assess early and potentially reversible changes in patients with defecation disorders.Keywords: defecation disorders, dynamic magnetic resonance defecography, anorectal manometry, anal electrical sensitivity tests, H line, M line
Procedia PDF Downloads 10613427 Adjustable Counter-Weight for Full Turn Rotary Systems
Authors: G. Karakaya, C. Türker, M. Anaklı
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It is necessary to test to see if optical devices such as camera, night vision devices are working properly. Therefore, a precision biaxial rotary system (gimbal) is required for mounting Unit Under Test, UUT. The Gimbal systems can be utilized for precise positioning of the UUT; hence, optical test can be performed with high accuracy. The weight of UUT, which is placed outside the axis of rotation, causes an off-axis moment to the mounting armature. The off-axis moment can act against the direction of movement for some orientation, thus the electrical motor, which rotates the gimbal axis, has to apply higher level of torque to guide and stabilize the system. Moreover, UUT and its mounting fixture to the gimbal can be changed, which causes change in applied resistance moment to the gimbals electrical motor. In this study, a preloaded spring is added to the gimbal system for minimizing applied off axis moment with the help of four bar mechanism. Two different possible methods for preloading spring are introduced and system optimization is performed to eliminate all moment which is created by off axis weight.Keywords: adaptive, balancing, gimbal, mechanics, spring
Procedia PDF Downloads 12113426 Numerical Analysis of Various V- rib Cross-section to Optimize Thermal Performance of the Rocket Engine
Authors: Hisham Elmouazen, Xiaobing Zhang
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In regenerative-cooled rocket engines, understanding the coolant behaviour within cooling channels is essential to enhance engine performance and maintain chamber walls at low temperatures. However, modelling and testing the rocket engine's cooling channels is challenging due to the high temperature of the chamber walls, supercritical flow, and high Reynolds number. Therefore, a numerical analysis of five different V-rib cross-sections to optimize rocket engine cooling channels' performance is developed and validated in this work. Three-dimensional CFD simulations are employed by the Shear Stress Transport (k- ω) turbulent model at Reynolds number 42,500. The study findings illustrate that the V-ribbed channel performance is optimized by 59.5% relative to the plain/flat channel. Additionally, the chamber wall temperature is decreased to 726.4 K, and the right-angle trapezoidal V-rib (Case 4) improves thermal augmentation up to 74.3 % with a slightly high friction factor.Keywords: computational fluid dynamics CFD, regenerative-cooled system, thermal performance, V-rib cross-sections
Procedia PDF Downloads 7513425 Optimization of Cu (In, Ga)Se₂ Based Thin Film Solar Cells: Simulation
Authors: Razieh Teimouri
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Electrical modelling of Cu (In,Ga)Se₂ thin film solar cells is carried out with compositionally graded absorber and CdS buffer layer. Simulation results are compared with experimental data. Surface defect layers (SDL) are located in CdS/CIGS interface for improving open circuit voltage simulated structure through the analysis of the interface is investigated with or without this layer. When SDL removed, by optimizing the conduction band offset (CBO) position of the buffer/absorber layers with its recombination mechanisms and also shallow donor density in the CdS, the open circuit voltage increased significantly. As a result of simulation, excellent performance can be obtained when the conduction band of window layer positions higher by 0.2 eV than that of CIGS and shallow donor density in the CdS was found about 1×10¹⁸ (cm⁻³).Keywords: CIGS solar cells, thin film, SCAPS, buffer layer, conduction band offset
Procedia PDF Downloads 23013424 Assessment of Music Performance Anxiety in Portuguese Children and Adolescents
Authors: Pedro Dias, Lurdes Verissimo, Maria Joao Baptista, Ana Pinheiro, Patricia Oliveira-Silva, Sofia Serra, Daniela Coimbra
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To achieve a high standard in performance, a musician must be well in all aspects of health (physical, mental and social). Anxiety in performance is related to the high level of coordination and skill needed in performance, as well as to the public evaluation of the performer. It affects some key elements of performance, such as concentration, memory, motor coordination, and relaxation. This work presents two studies focused on the adaptation and evaluation of the psychometric properties of the Music Performance Anxiety Inventory (MPAI-A) in young Portuguese music students. The first study was conducted with a sample of 161 adolescent music students, who responded to the Portuguese version of this instrument, and to the State-Trait Anxiety Inventory for Children (STAIC-c2). Validity and reliability were examined, and this measure revealed robust psychometric properties in this sample. The second study aimed to adapt the MPAI to a younger population (one hundred 8-10 years-old music students). Again, the MPAI and the STAIC c-2 were used in this study. Exploratory factor analysis, correlations, and internal consistency were used to evaluate the final children version of the instrument (MPAI-C), presenting a different factor structure compared to the adolescent version (10 items organized in 2 factors) and high levels of reliability and convergent validity.Keywords: anxiety, assessment, children and adolescents, music performance
Procedia PDF Downloads 19013423 Digital Divide and Its Impact on the Students’ Performance
Authors: Aissa Hanifi
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People across different world societies are using information and communication technology (ICT) for different purposes. Unfortunately, in contemporary societies, some people have little access to ICT and thus cannot have effective participation in society compared with those who have better access. The purpose of this study is to test the impact of ICTs on university life in general and students' performance in particular. The study relied on an online survey questionnaire that was administered to 30 undergraduate students at Chef University. The findings of the survey revealed that there is still an important number of students who do not have easy access to ICT. Such limited access to ICTs is attributed to varied factors. Some students live in rural areas, where due to the poor internet coverage, they face difficulties in competing with students who live in urban areas with better ICT access. The lack of ICT access has hindered the students' university performance in general and their language skills, and the exchange of information with teachers and classmates.Keywords: access, communication, ICT, performance, technology
Procedia PDF Downloads 12813422 Performance Analysis with the Combination of Visualization and Classification Technique for Medical Chatbot
Authors: Shajida M., Sakthiyadharshini N. P., Kamalesh S., Aswitha B.
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Natural Language Processing (NLP) continues to play a strategic part in complaint discovery and medicine discovery during the current epidemic. This abstract provides an overview of performance analysis with a combination of visualization and classification techniques of NLP for a medical chatbot. Sentiment analysis is an important aspect of NLP that is used to determine the emotional tone behind a piece of text. This technique has been applied to various domains, including medical chatbots. In this, we have compared the combination of the decision tree with heatmap and Naïve Bayes with Word Cloud. The performance of the chatbot was evaluated using accuracy, and the results indicate that the combination of visualization and classification techniques significantly improves the chatbot's performance.Keywords: sentimental analysis, NLP, medical chatbot, decision tree, heatmap, naïve bayes, word cloud
Procedia PDF Downloads 7413421 Electrochemistry and Performance of Bryophylum pinnatum Leaf (BPL) Electrochemical Cell
Authors: M. A. Mamun, M. I. Khan, M. H. Sarker, K. A. Khan, M. Shajahan
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The study was carried out to investigate on an innovative invention, Pathor Kuchi Leaf (PKL) cell, which is fueled with PKL sap of widely available plant called Bryophyllum pinnatum as an energy source for use in PKL battery to generate electricity. This battery, a primary source of electricity, has several order of magnitude longer shelf-lives than the traditional Galvanic cell battery, is still under investigation. In this regard, we have conducted some experiments using various instruments including Atomic Absorption Spectrophotometer (AAS), Ultra-Violet Visible spectrophotometer (UV-Vis), pH meter, Ampere-Volt-Ohm Meter (AVO Meter), etc. The AAS, UV-Vis, and pH-metric analysis data provided that the potential and current were produced as the Zn electrode itself acts as reductant while Cu2+ and H+ ions are behaving as the oxidant. The significant influence of secondary salt on current and potential leads to the dissociation of weak organic acids in PKL juice, and subsequent enrichment to the reactant ions by the secondary salt effects. However, the liquid junction potential was not as great as minimized with the opposite transference of organic acid anions and H+ ions as their dissimilar ionic mobilities. Moreover, the large value of the equilibrium constant (K) implies the big change in Gibbs free energy (∆G), the more electromotive force works in electron transfer during the forward electrochemical reaction which coincides with the fast reduction of the weight of zinc plate, revealed the additional electrical work in the presence of PKL sap. This easily fabricated high-performance PKL battery can show an excellent promise during the off-peak across the countryside.Keywords: Atomic Absorption Spectrophotometer (AAS), Bryophylum Pinnatum Leaf (BPL), electricity, electrochemistry, organic acids
Procedia PDF Downloads 32513420 Seismic Performance Evaluation of Existing Building Using Structural Information Modeling
Authors: Byungmin Cho, Dongchul Lee, Taejin Kim, Minhee Lee
Abstract:
The procedure for the seismic retrofit of existing buildings includes the seismic evaluation. In the evaluation step, it is assessed whether the buildings have satisfactory performance against seismic load. Based on the results of that, the buildings are upgraded. To evaluate seismic performance of the buildings, it usually goes through the model transformation from elastic analysis to inelastic analysis. However, when the data is not delivered through the interwork, engineers should manually input the data. In this process, since it leads to inaccuracy and loss of information, the results of the analysis become less accurate. Therefore, in this study, the process for the seismic evaluation of existing buildings using structural information modeling is suggested. This structural information modeling makes the work economic and accurate. To this end, it is determined which part of the process could be computerized through the investigation of the process for the seismic evaluation based on ASCE 41. The structural information modeling process is developed to apply to the seismic evaluation using Perform 3D program usually used for the nonlinear response history analysis. To validate this process, the seismic performance of an existing building is investigated.Keywords: existing building, nonlinear analysis, seismic performance, structural information modeling
Procedia PDF Downloads 38413419 Reflector Arrangement Effect on Ultraviolet Lamp Performance by CFX Simulation
Authors: William Sidharta, Chin-Tu Lu
Abstract:
Fluorescent ultraviolet lamp generates ultraviolet light which is commonly used in industrial field with certain purposes especially for curing process. Due to the value of inefficiency, there are changes in energy from electrical energy to the heat energy and this would make a defect on the industrial product caused by high temperature of lamp tube during ultraviolet light emission. The condition of industrial scale is further worsening, since commonly using dozens of fluorescent ultraviolet lamps to support huge production process and then it will generates much more heat energy. The maximum temperature of fluorescent ultraviolet lamp will get affected by arranging the lamp tube reflector and this study presents CFX simulation results of the maximum lamp tube temperature with some different reflector arrangements on purely natural convection phenomena. There exists certain spaces value of the reflector and the lamp tube to obtaining lower maximum temperature of the fluorescent ultraviolet lamp.Keywords: CFX simulation, fluorescent UV lamp, lamp tube reflector, UV light
Procedia PDF Downloads 465