Search results for: physico-chemical characteristics
5206 Empirical Research on Preference for Conflict Resolution Styles of Owners and Contractors in China
Authors: Junqi Zhao, Yongqiang Chen
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The preference for different conflict resolution styles are influenced by cultural background and power distance of two parties involving in conflict. This research put forward 7 hypotheses and tested the preference differences of the five conflict resolution styles between Chinese owner and contractor as well as the preference differences concerning the same style between two parties. The research sample includes 202 practitioners from construction enterprises in mainland China. Research result found that theories concerning conflict resolution styles could be applied in the Chinese construction industry. Some results of this research were not in line with former research, and this research also gave explanation to the differences from the characteristics of construction projects. Based on the findings, certain suggestions were made to serve as a guidance for managers to choose appropriate conflict resolution styles for a better handling of conflict.Keywords: Chinese owner and contractor, conflict, construction project, conflict resolution styles
Procedia PDF Downloads 5345205 Leadership in Future Operational Environment
Authors: M. Şimşek
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Rapidly changing factors that affect daily life also affect operational environment and the way military leaders fulfill their missions. With the help of technological developments, traditional linearity of conflict and war has started to fade away. Furthermore, mission domain has broadened to include traditional threats, hybrid threats and new challenges of cyber and space. Considering the future operational environment, future military leaders need to adapt themselves to the new challenges of the future battlefield. But how to decide what kind of features of leadership are required to operate and accomplish mission in the new complex battlefield? In this article, the main aim is to provide answers to this question. To be able to find right answers, first leadership and leadership components are defined, and then characteristics of future operational environment are analyzed. Finally, leadership features that are required to be successful in redefined battlefield are explained.Keywords: future operational environment, leadership, leadership components
Procedia PDF Downloads 4365204 Combined Odd Pair Autoregressive Coefficients for Epileptic EEG Signals Classification by Radial Basis Function Neural Network
Authors: Boukari Nassim
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This paper describes the use of odd pair autoregressive coefficients (Yule _Walker and Burg) for the feature extraction of electroencephalogram (EEG) signals. In the classification: the radial basis function neural network neural network (RBFNN) is employed. The RBFNN is described by his architecture and his characteristics: as the RBF is defined by the spread which is modified for improving the results of the classification. Five types of EEG signals are defined for this work: Set A, Set B for normal signals, Set C, Set D for interictal signals, set E for ictal signal (we can found that in Bonn university). In outputs, two classes are given (AC, AD, AE, BC, BD, BE, CE, DE), the best accuracy is calculated at 99% for the combined odd pair autoregressive coefficients. Our method is very effective for the diagnosis of epileptic EEG signals.Keywords: epilepsy, EEG signals classification, combined odd pair autoregressive coefficients, radial basis function neural network
Procedia PDF Downloads 3475203 Photoplethysmography-Based Device Designing for Cardiovascular System Diagnostics
Authors: S. Botman, D. Borchevkin, V. Petrov, E. Bogdanov, M. Patrushev, N. Shusharina
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In this paper, we report the development of the device for diagnostics of cardiovascular system state and associated automated workstation for large-scale medical measurement data collection and analysis. It was shown that optimal design for the monitoring device is wristband as it represents engineering trade-off between accuracy and usability. The monitoring device is based on the infrared reflective photoplethysmographic sensor, which allows collecting multiple physiological parameters, such as heart rate and pulsing wave characteristics. Developed device use BLE interface for medical and supplementary data transmission to the coupled mobile phone, which process it and send it to the doctor's automated workstation. Results of this experimental model approbation confirmed the applicability of the proposed approach.Keywords: cardiovascular diseases, health monitoring systems, photoplethysmography, pulse wave, remote diagnostics
Procedia PDF Downloads 4955202 Relationship and Comorbidity Between Down Syndrome and Autism Spectrum Disorder
Authors: Javiera Espinosa, Patricia López, Noelia Santos, Nadia Loro, Esther Moraleda
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In recent years, there has been a notable increase in the number of investigations that establish that Down Syndrome and Autism Spectrum Disorder are diagnoses that can coexist together. However, there are also many studies that consider that both diagnoses present neuropsychological, linguistic and adaptive characteristics with a totally different profile. The objective of this research is to question whether there really can be a profile that encompasses both disorders or if they can be incompatible with each other. To this end, a review of the scientific literature of recent years has been carried out. The results indicate that the two lines collect opposite approaches. On the one hand, there is research that supports the increase in comorbidity between Down Syndrome and Autism Spectrum Disorder, and on the other hand, many investigations show a totally different general development profile between the two. The discussion focuses on discussing both lines of work and on proposing future lines of research in this regard.Keywords: disability, language, speech, down syndrome
Procedia PDF Downloads 745201 Electromagnetic Assessment of Submarine Power Cable Degradation Using Finite Element Method and Sensitivity Analysis
Authors: N. Boutra, N. Ravot, J. Benoit, O. Picon
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Submarine power cables used for offshore wind farms electric energy distribution and transmission are subject to numerous threats. Some of the risks are associated with transport, installation and operating in harsh marine environment. This paper describes the feasibility of an electromagnetic low frequency sensing technique for submarine power cable failure prediction. The impact of a structural damage shape and material variability on the induced electric field is evaluated. The analysis is performed by modeling the cable using the finite element method, we use sensitivity analysis in order to identify the main damage characteristics affecting electric field variation. Lastly, we discuss the results obtained.Keywords: electromagnetism, finite element method, sensitivity analysis, submarine power cables
Procedia PDF Downloads 3575200 Balancing and Synchronization Control of a Two Wheel Inverted Pendulum Vehicle
Authors: Shiuh-Jer Huang, Shin-Ham Lee, Sheam-Chyun Lin
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A two wheel inverted pendulum (TWIP) vehicle is built with two hub DC motors for motion control evaluation. Arduino Nano micro-processor is chosen as the control kernel for this electric test plant. Accelerometer and gyroscope sensors are built in to measure the tilt angle and angular velocity of the inverted pendulum vehicle. Since the TWIP has significantly hub motor dead zone and nonlinear system dynamics characteristics, the vehicle system is difficult to control by traditional model based controller. The intelligent model-free fuzzy sliding mode controller (FSMC) was employed as the main control algorithm. Then, intelligent controllers are designed for TWIP balance control, and two wheels synchronization control purposes.Keywords: balance control, synchronization control, two-wheel inverted pendulum, TWIP
Procedia PDF Downloads 3985199 Musical Notation Reading versus Alphabet Reading-Comparison and Implications for Teaching Music Reading to Students with Dyslexia
Authors: Ora Geiger
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Reading is a cognitive process of deciphering visual signs to produce meaning. During the reading process, written information of symbols and signs is received in the person’s eye and processed in the brain. This definition is relevant to both the reading of letters and the reading of musical notation. But while the letters of the alphabet are signs determined arbitrarily, notes are recorded systematically on a staff, with the location of each note on the staff indicating its relative pitch. In this paper, the researcher specifies the characteristics of alphabet reading in comparison to musical notation reading, and discusses the question whether a person diagnosed with dyslexia will necessarily have difficulty in reading musical notes. Dyslexia is a learning disorder that makes it difficult to acquire alphabet-reading skills due to difficulties expressed in the identification of letters, spelling, and other language deciphering skills. In order to read, one must be able to connect a symbol with a sound and to join the sounds into words. A person who has dyslexia finds it difficult to translate a graphic symbol into the sound that it represents. When teaching reading to children diagnosed with dyslexia, the multi-sensory approach, supporting the activation and involvement of most of the senses in the learning process, has been found to be particularly effective. According to this approach, when most senses participate in the reading learning process, it becomes more effective. During years of experience, the researcher, who is a music specialist, has been following the music reading learning process of elementary school age students, some of them diagnosed with Dyslexia, while studying to play soprano (descant) recorder. She argues that learning music reading while studying to play a musical instrument is a multi-sensory experience by its nature. The senses involved are: sight, hearing, touch, and the kinesthetic sense (motion), which provides the brain with information on the relative positions of the body. In this way, the learner experiences simultaneously visual, auditory, tactile, and kinesthetic impressions. The researcher concludes that there should be no contra-indication for teaching standard music reading to children with dyslexia if an appropriate process is offered. This conclusion is based on two main characteristics of music reading: (1) musical notation system is a systematic, logical, relative set of symbols written on a staff; and (2) music reading learning connected with playing a musical instrument is by its nature a multi-sensory activity since it combines sight, hearing, touch, and movement. This paper describes music reading teaching procedures and provides unique teaching methods that have been found to be effective for students who were diagnosed with Dyslexia. It provides theoretical explanations in addition to guidelines for music education practices.Keywords: alphabet reading, dyslexia, multisensory teaching method, music reading, recorder playing
Procedia PDF Downloads 3665198 Using Divergent Nozzle with Aerodynamic Lens to Focus Nanoparticles
Authors: Hasan Jumaah Mrayeh, Fue-Sang Lien
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ANSYS Fluent will be used to simulate Computational Fluid Dynamics (CFD) for an efficient lens and nozzle design which will be explained in this paper. We have designed and characterized an aerodynamic lens and a divergent nozzle for focusing flow that transmits sub 25 nm particles through the aerodynamic lens. The design of the lens and nozzle has been improved using CFD for particle trajectories. We obtained a case for calculating nanoparticles (25 nm) flowing through the aerodynamic lens and divergent nozzle. Nanoparticles are transported by air, which is pumped into the aerodynamic lens through the nozzle at 1 atmospheric pressure. We have also developed a computational methodology that can determine the exact focus characteristics of aerodynamic lens systems. Particle trajectories were traced using the Lagrange approach. The simulation shows the ability of the aerodynamic lens to focus on 25 nm particles after using a divergent nozzle.Keywords: aerodynamic lens, divergent nozzle, ANSYS Fluent, Lagrange approach
Procedia PDF Downloads 3085197 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 805196 Highly Selective Polymeric Fluorescence Sensor for Cd(II) Ions
Authors: Soner Cubuk, Ozge Yilmaz, Ece Kok Yetimoglu, M. Vezir Kahraman
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In this work, a polymer based highly selective fluorescence sensor membrane was prepared by the photopolymerization technique for the determination Cd(II) ion. Sensor characteristics such as effects of pH, response time and foreign ions on the fluorescence intensity of the sensor were also studied. Under optimized conditions, the polymeric sensor shows a rapid, stable and linear response for 4.45x10-⁹ mol L-¹ - 4.45x10-⁸ mol L-¹ Cd(II) ion with the detection limit of 6.23x10-¹⁰ mol L-¹. In addition, sensor membrane was selective which is not affected by common foreign metal ions. The concentrations of the foreign ions such as Pb²+, Co²+, Ag+, Zn²+, Cu²+, Cr³+ are 1000-fold higher than Cd(II) ions. Moreover, the developed polymeric sensor was successfully applied to the determination of cadmium ions in food and water samples. This work was supported by Marmara University, Commission of Scientific Research Project.Keywords: cadmium(II), fluorescence, photopolymerization, polymeric sensor
Procedia PDF Downloads 5675195 Improved Estimation Strategies of Sensitive Characteristics Using Scrambled Response Techniques in Successive Sampling
Authors: S. Suman, G. N. Singh
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This research work is an effort to analyse the consequences of scrambled response technique to estimate the current population mean in two-occasion successive sampling when the characteristic of interest is sensitive in nature. The generalized estimation procedures have been proposed using sensitive auxiliary variables under additive and multiplicative scramble models. The properties of resultant estimators have been deeply examined. Simulation, as well as empirical studies, are carried out to evaluate the performances of the proposed estimators with respect to other competent estimators. The results of our studies suggest that the proposed estimation procedures are highly effective under the presence of non-response situation. The result of this study also suggests that additive scrambled response model is a better choice in the perspective of cost of the survey and privacy of the respondents.Keywords: scrambled response, sensitive characteristic, successive sampling, optimum replacement strategy
Procedia PDF Downloads 1805194 Modeling and Simulations of Surface Plasmon Waveguide Structures
Authors: Moussa Hamdan, Abdulati Abdullah
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This paper presents an investigation of the fabrication of the optical devices in terms of their characteristics based on the use of the electromagnetic waves. Planar waveguides are used to examine the field modes (bound modes) and the parameters required for this structure. The modifications are conducted on surface plasmons based waveguides. Simple symmetric dielectric slab structure is used and analyzed in terms of transverse electric mode (TE-Mode) and transverse magnetic mode (TM-Mode. The paper presents mathematical and numerical solutions for solving simple symmetric plasmons and provides simulations of surface plasmons for field confinement. Asymmetric TM-mode calculations for dielectric surface plasmons are also provided.Keywords: surface plasmons, optical waveguides, semiconductor lasers, refractive index, slab dialectical
Procedia PDF Downloads 3065193 Mutual Coupling Reduction between Patch Antenna Array Elements Using Metamaterial Z Shaped Resonators
Authors: Oossama Tabbabi, Mondher Labidi, Fethi Choubani, J. David
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Modern wireless communication systems require compact design, low cost and simple structure antennas to insure reliability, agility, and high efficiency characteristics. This paper presents a microstrip antenna array designed for 8 GHz applications. To reduce the mutual coupling effects, a Z shape metamaterial structure was imprinted in the microstrip antenna array composed of two elements. Simulation results show the improvement of mutual coupling by adding Z shape metamaterial structure to the antenna substrate. The proposed structure reduces mutual coupling by 19 dB. The simulation has been performed by using HFSS simulator.Keywords: antenna array, compact design, modern wireless communication, mutual coupling effects
Procedia PDF Downloads 3435192 Structural-Geotechnical Effects of the Foundation of a Medium-Height Structure
Authors: Valentina Rodas, Luis Almache
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The interaction effects between the existing soil and the substructure of a 5-story building with an underground one were evaluated in such a way that the structural-geotechnical concepts were validated through the method of impedance factors with a program based on the method of the finite elements. The continuous wall-type foundation had a constant thickness and followed inclined and orthogonal directions, while the ground had homogeneous and medium-type characteristics. The soil considered was type C according to the Ecuadorian Construction Standard (NEC) and the corresponding foundation comprised a depth of 4.00 meters and a basement wall thickness of 40 centimeters. This project is part of a mid-rise building in the city of Azogues (Ecuador). The hypotheses raised responded to the objectives in such a way that the model implemented with springs had a variation with respect to the embedded base, obtaining conservative results.Keywords: interaction, soil, substructure, springs, effects, modeling , embedment
Procedia PDF Downloads 2325191 Study on Network-Based Technology for Detecting Potentially Malicious Websites
Authors: Byung-Ik Kim, Hong-Koo Kang, Tae-Jin Lee, Hae-Ryong Park
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Cyber terrors against specific enterprises or countries have been increasing recently. Such attacks against specific targets are called advanced persistent threat (APT), and they are giving rise to serious social problems. The malicious behaviors of APT attacks mostly affect websites and penetrate enterprise networks to perform malevolent acts. Although many enterprises invest heavily in security to defend against such APT threats, they recognize the APT attacks only after the latter are already in action. This paper discusses the characteristics of APT attacks at each step as well as the strengths and weaknesses of existing malicious code detection technologies to check their suitability for detecting APT attacks. It then proposes a network-based malicious behavior detection algorithm to protect the enterprise or national networks.Keywords: Advanced Persistent Threat (APT), malware, network security, network packet, exploit kits
Procedia PDF Downloads 3705190 An Improvement of Multi-Label Image Classification Method Based on Histogram of Oriented Gradient
Authors: Ziad Abdallah, Mohamad Oueidat, Ali El-Zaart
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Image Multi-label Classification (IMC) assigns a label or a set of labels to an image. The big demand for image annotation and archiving in the web attracts the researchers to develop many algorithms for this application domain. The existing techniques for IMC have two drawbacks: The description of the elementary characteristics from the image and the correlation between labels are not taken into account. In this paper, we present an algorithm (MIML-HOGLPP), which simultaneously handles these limitations. The algorithm uses the histogram of gradients as feature descriptor. It applies the Label Priority Power-set as multi-label transformation to solve the problem of label correlation. The experiment shows that the results of MIML-HOGLPP are better in terms of some of the evaluation metrics comparing with the two existing techniques.Keywords: data mining, information retrieval system, multi-label, problem transformation, histogram of gradients
Procedia PDF Downloads 3765189 Shear Strength Envelope Characteristics of LimeTreated Clays
Authors: Mohammad Moridzadeh, Gholamreza Mesri
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The effectiveness of lime treatment of soils has been commonly evaluated in terms of improved workability and increased undrained unconfined compressive strength in connection to road and airfield construction. The most common method of strength measurement has been the unconfined compression test. However, if the objective of lime treatment is to improve long-term stability of first-time or reactivated landslides in stiff clays and shales, permanent changes in the size and shape of clay particles must be realized to increase drained frictional resistance. Lime-soil interactions that may produce less platy and larger soil particles begin and continue with time under the highly alkaline pH environment. In this research, pH measurements are used to monitor chemical environment and progress of reactions. Atterberg limits are measured to identify changes in particle size and shape indirectly. Also, fully softened and residual strength measurements are used to examine an improvement in frictional resistance due to lime-soil interactions. The main variables are soil plasticity and mineralogy, lime content, water content, and curing period. Lime effect on frictional resistance is examined using samples of clays with different mineralogy and characteristics which may react with lime to various extents. Drained direct shear tests on reconstituted lime-treated clay specimens with various properties have been performed to measure fully softened shear strength. To measure residual shear strength, drained multiple reversal direct shear tests on precut specimens were conducted. This way, soil particles are oriented along the direction of shearing to the maximum possible extent and provide minimum frictional resistance. This is applicable to reactivated and part of first-time landslides. The Brenna clay, which is the highly plastic lacustrine clay of Lake Agassiz causing slope instability along the banks of the Red River, is one of the soil samples used in this study. The Brenna Formation characterized as a uniform, soft to firm, dark grey, glaciolacustrine clay with little or no visible stratification, is full of slickensided surfaces. The major source of sediment for the Brenna Formation was the highly plastic montmorillonitic Pierre Shale bedrock. The other soil used in this study is one of the main sources of slope instability in Harris County Flood Control District (HCFCD), i.e. the Beaumont clay. The shear strengths of untreated and treated clays were obtained under various normal pressures to evaluate the shear envelope nonlinearity.Keywords: Brenna clay, friction resistance, lime treatment, residual
Procedia PDF Downloads 1605188 Toward a New Approach for Modeling Lean, Agile and Leagile Supply Chains
Authors: Bouchra Abdelilah, Akram El Korchi, Atmane Baddou
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With the very competitive business era that we witness nowadays, companies needs more that anytime to use all the resources they have in order to maximize performance and satisfy the customers’ needs. The changes occurring in the market business are often due to the variations of demand, which requires a very specific supply chain strategy. Supply chains aims to balance cost, quality, and service level and lead time. Still, managers are confused when faced with the strategies working the best for the supply chain: lean, agile and leagile. This paper presents a decision making tool that aims to assist the manager in choosing the supply chain strategy that suits the most his business, depending on the type of product and the nature of demand. Analyzing the different characteristics of supply chain will enable us to guide the manager to the suitable strategy between lean, agile and leagile.Keywords: supply chain, lean, agile, flexibility, performance
Procedia PDF Downloads 8615187 Discovery of the Piano Extended Techniques by Focusing on Symbols That George Crumb Used in Makrokosmos Volumes
Authors: Parham Bakhtiari
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George Crumb's Makrokosmos Volumes are considered significant pieces in twentieth-century piano music and showcase the extensive use of different tones and extended techniques on the piano. Crumb's works are known for making references, particularly to music from previous eras which the visual, aural, and numerical characteristics are symbolic in nature. Crumb created a list of symbols and shortened letters to clarify his unique directions to those who performed his compositions. The pianists who prepare to play Makrokosmos must dedicate time to study and analyze Crumb's markings diligently to accurately capture the composer's wishes. The aim of this paper is to provide a collection for pianists looking to perform George Crumb's compositions known as Makrokosmos Volumes. The research traits of unconventional playing techniques and discussions on the music explored by the composer are being described.Keywords: music, piano, Crumb, Makrokosmos, performance
Procedia PDF Downloads 525186 Additive Manufacturing – Application to Next Generation Structured Packing (SpiroPak)
Authors: Biao Sun, Tejas Bhatelia, Vishnu Pareek, Ranjeet Utikar, Moses Tadé
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Additive manufacturing (AM), commonly known as 3D printing, with the continuing advances in parallel processing and computational modeling, has created a paradigm shift (with significant radical thinking) in the design and operation of chemical processing plants, especially LNG plants. With the rising energy demands, environmental pressures, and economic challenges, there is a continuing industrial need for disruptive technologies such as AM, which possess capabilities that can drastically reduce the cost of manufacturing and operations of chemical processing plants in the future. However, the continuing challenge for 3D printing is its lack of adaptability in re-designing the process plant equipment coupled with the non-existent theory or models that could assist in selecting the optimal candidates out of the countless potential fabrications that are possible using AM. One of the most common packings used in the LNG process is structured packing in the packed column (which is a unit operation) in the process. In this work, we present an example of an optimum strategy for the application of AM to this important unit operation. Packed columns use a packing material through which the gas phase passes and comes into contact with the liquid phase flowing over the packing, typically performing the necessary mass transfer to enrich the products, etc. Structured packing consists of stacks of corrugated sheets, typically inclined between 40-70° from the plane. Computational Fluid Dynamics (CFD) was used to test and model various geometries to study the governing hydrodynamic characteristics. The results demonstrate that the costly iterative experimental process can be minimized. Furthermore, they also improve the understanding of the fundamental physics of the system at the multiscale level. SpiroPak, patented by Curtin University, represents an innovative structured packing solution currently at a technology readiness level (TRL) of 5~6. This packing exhibits remarkable characteristics, offering a substantial increase in surface area while significantly enhancing hydrodynamic and mass transfer performance. Recent studies have revealed that SpiroPak can reduce pressure drop by 50~70% compared to commonly used commercial packings, and it can achieve 20~50% greater mass transfer efficiency (particularly in CO2 absorption applications). The implementation of SpiroPak has the potential to reduce the overall size of columns and decrease power consumption, resulting in cost savings for both capital expenditure (CAPEX) and operational expenditure (OPEX) when applied to retrofitting existing systems or incorporated into new processes. Furthermore, pilot to large-scale tests is currently underway to further advance and refine this technology.Keywords: Additive Manufacturing (AM), 3D printing, Computational Fluid Dynamics (CFD, structured packing (SpiroPak)
Procedia PDF Downloads 925185 Critical and Strategic Issues in Compensation, Staffing and Personnel Management in Nigeria
Authors: Shonuga Olajumoke Adedoyinsola
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Staffing and Compensation are at the core of any employment exchange, and they serve as the defining characteristics of any employment relationship. Most organizations understand the benefits that a longer term approach to staff planning can bring and the answer to this problem lies not in trying to implement the traditional approach more effectively, but in implementing a completely different kind of process for strategic staffing. The study focuses on critical points of compensation, staffing and personnel management. The fundamentals of these programs include the elements of vision, potential, communication and motivation. The aim of the paper is to identify the most important attributes of compensation and incentives, staffing and personnel management. Research method is the analysis and synthesis of scientific literature, logical, comparative and graphic representation. On the basis of analysis, the author presents the models of these systems for positive employee attitudes and behaviors.Keywords: compensation, employees, incentives, staffing, personnel management
Procedia PDF Downloads 3015184 Computational Modeling of Combustion Wave in Nanoscale Thermite Reaction
Authors: Kyoungjin Kim
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Nanoscale thermites such as the composite mixture of nano-sized aluminum and molybdenum trioxide powders possess several technical advantages such as much higher reaction rate and shorter ignition delay, when compared to the conventional energetic formulations made of micron-sized metal and oxidizer particles. In this study, the self-propagation of combustion wave in compacted pellets of nanoscale thermite composites is modeled and computationally investigated by utilizing the activation energy reduction of aluminum particles due to nanoscale particle sizes. The present computational model predicts the speed of combustion wave propagation which is good agreement with the corresponding experiments of thermite reaction. Also, several characteristics of thermite reaction in nanoscale composites are discussed including the ignition delay and combustion wave structures.Keywords: nanoparticles, thermite reaction, combustion wave, numerical modeling
Procedia PDF Downloads 3805183 Virtualization of Production Using Digital Twin Technology
Authors: Bohuslava Juhasova, Igor Halenar, Martin Juhas
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The contribution deals with the current situation in modern manufacturing enterprises, which is affected by digital virtualization of different parts of the production process. The overview part of this article points to the fact, that wide informatization of all areas causes substitution of real elements and relationships between them with their digital, often virtual images, in real practice. Key characteristics of the systems implemented using digital twin technology along with essential conditions for intelligent products deployment were identified across many published studies. The goal was to propose a template for the production system realization using digital twin technology as a supplement to standardized concepts for Industry 4.0. The main resulting idea leads to the statement that the current trend of implementation of the new technologies and ways of communication between industrial facilities erases the boundaries between the real environment and the virtual world.Keywords: communication, digital twin, Industry 4.0, simulation, virtualization
Procedia PDF Downloads 2515182 ANSYS Investigation on Stability and Performance of a Solar Driven Inline Alpha Stirling Engine
Authors: Joseph Soliman, Youssef Attia, Khairy Megalla
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The stable operation of an inline Stirling engine will be achieved when both engine configurations and operating conditions are optimum. This paper presents stability and performance investigation of an inline Stirling engine using ANSYS. Dynamic motion of engine pistons such as the displacer and the power piston are both obtained. For engine design, the optimum parameters are given such as engine specifications, engine characteristics and working conditions to yield the maximum efficiency and reliability. The prototype was built and tested and it is used as a validation case. The comparison of both experimental and simulation results are provided and discussed. Results were found to be encouraging to initiate a Stirling engine project for 3 kW power output. The working fluids are air, hydrogen, nitrogen and helum.Keywords: stirling engine, solar energy, new energy, dynamic motion
Procedia PDF Downloads 4245181 The Effects of Dual-Enrollment Programs on Students’ Post-Secondary Academic Performance
Authors: Cody Kirby, Kaustav Misra, Arundhati Bagchi Misra, Sharon P. Cox
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This paper focuses on the relationship that dual-enrollment programs have on academic performance and retention. Both performance and retention are significant issues in higher education. The first, performance, is a goal of higher education, having an impact on students’ lives. The second, retention, is key to the viability of any college or university. This paper uses survey research methodology to examine factors that lead to positive student academic performance, which leads to retention, specifically in dual-enrollment programs. The data show several characteristics that lead to a positive impact on GPA. These include the following; age, Caucasian race, full-time status, students in STEM programs, and finally dual enrollment participation.Keywords: dual enrollment, early college, retention, undergraduate education
Procedia PDF Downloads 1515180 Machine Learning Techniques in Seismic Risk Assessment of Structures
Authors: Farid Khosravikia, Patricia Clayton
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The main objective of this work is to evaluate the advantages and disadvantages of various machine learning techniques in two key steps of seismic hazard and risk assessment of different types of structures. The first step is the development of ground-motion models, which are used for forecasting ground-motion intensity measures (IM) given source characteristics, source-to-site distance, and local site condition for future events. IMs such as peak ground acceleration and velocity (PGA and PGV, respectively) as well as 5% damped elastic pseudospectral accelerations at different periods (PSA), are indicators of the strength of shaking at the ground surface. Typically, linear regression-based models, with pre-defined equations and coefficients, are used in ground motion prediction. However, due to the restrictions of the linear regression methods, such models may not capture more complex nonlinear behaviors that exist in the data. Thus, this study comparatively investigates potential benefits from employing other machine learning techniques as statistical method in ground motion prediction such as Artificial Neural Network, Random Forest, and Support Vector Machine. The results indicate the algorithms satisfy some physically sound characteristics such as magnitude scaling distance dependency without requiring pre-defined equations or coefficients. Moreover, it is shown that, when sufficient data is available, all the alternative algorithms tend to provide more accurate estimates compared to the conventional linear regression-based method, and particularly, Random Forest outperforms the other algorithms. However, the conventional method is a better tool when limited data is available. Second, it is investigated how machine learning techniques could be beneficial for developing probabilistic seismic demand models (PSDMs), which provide the relationship between the structural demand responses (e.g., component deformations, accelerations, internal forces, etc.) and the ground motion IMs. In the risk framework, such models are used to develop fragility curves estimating exceeding probability of damage for pre-defined limit states, and therefore, control the reliability of the predictions in the risk assessment. In this study, machine learning algorithms like artificial neural network, random forest, and support vector machine are adopted and trained on the demand parameters to derive PSDMs for them. It is observed that such models can provide more accurate estimates of prediction in relatively shorter about of time compared to conventional methods. Moreover, they can be used for sensitivity analysis of fragility curves with respect to many modeling parameters without necessarily requiring more intense numerical response-history analysis.Keywords: artificial neural network, machine learning, random forest, seismic risk analysis, seismic hazard analysis, support vector machine
Procedia PDF Downloads 1075179 Pressure Regulator Optimization in LPG Fuel Injection Systems
Authors: M. Akif Ceviz, Alirıza Kaleli, Erdoğan Güner
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LPG pressure regulator is a device which is used to change the phase of LPG from liquid to gas by decreasing the pressure. During the phase change, it is necessary to supply the latent heat of LPG to prevent excessive low temperature. Engine coolant is circulated in the pressure regulator for this purpose. Therefore, pressure regulator is a type of heat exchanger that should be designed for different engine operating conditions. The design of the regulator should ensure that the flow of LPG is in gaseous phase to the injectors during the engine steady state and transient operating conditions. The pressure regulators in the LPG gaseous injection systems currently used can easily change the phase of LPG, however, there is no any control on the LPG temperature in conventional LPG injection systems. It is possible to increase temperature excessively. In this study, a control unit has been tested to keep the LPG temperature in a band. Result of the study showed that the engine performance characteristics can be increased by using the system.Keywords: temperature, pressure regulator, LPG, PID
Procedia PDF Downloads 5165178 Preparation and Characterization of Polyaniline (PANI) – Platinum Nanocomposite
Authors: Kumar Neeraj, Ranjan Haldar, Ashok Srivastava
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Polyaniline used as light-emitting devices (LEDs), televisions, cellular telephones, automotive, Corrosion-resistant coatings, actuators and ability to have micro- and nano-devices. the electrical conductivity properties can be increased by introduction of metal nano particles. In the present study, platinum nano particles have been utilized to achieve the improved properties. Polyaniline and Pt-polyaniline composite are synthesized by chemical routes. The samples characterized by X-ray diffractometer show the amorphous nature of polyaniline and Pt-polyaniline composite. The Bragg’s diffraction peaks correspond to platinum nano particles and thermogravimetric analyzer predicts its decomposition at certain temperature. The current-potential characteristics of the samples are also studied which indicate a significant increasing the value of conductivity after introduction of pt nanoparticles in the matrix of polyaniline (PANI).Keywords: polyaniline, XRD and platinum nanoparticles, characterization, pharmaceutical sciences
Procedia PDF Downloads 5465177 Speaker Recognition Using LIRA Neural Networks
Authors: Nestor A. Garcia Fragoso, Tetyana Baydyk, Ernst Kussul
Abstract:
This article contains information from our investigation in the field of voice recognition. For this purpose, we created a voice database that contains different phrases in two languages, English and Spanish, for men and women. As a classifier, the LIRA (Limited Receptive Area) grayscale neural classifier was selected. The LIRA grayscale neural classifier was developed for image recognition tasks and demonstrated good results. Therefore, we decided to develop a recognition system using this classifier for voice recognition. From a specific set of speakers, we can recognize the speaker’s voice. For this purpose, the system uses spectrograms of the voice signals as input to the system, extracts the characteristics and identifies the speaker. The results are described and analyzed in this article. The classifier can be used for speaker identification in security system or smart buildings for different types of intelligent devices.Keywords: extreme learning, LIRA neural classifier, speaker identification, voice recognition
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