Search results for: Sustainable energy
1423 The Effect of Natural Light on the Performance of Visible Light Communication Systems
Authors: Mahmoud Beshr, Ivan Andonovic, Moustafa H. Aly
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Visible Light Communication (VLC) offers advantages of low energy consumption, licence free and RF interference free operation. One application area for VLC is in the provision of health centred services circumventing issues of interference with any biomedical device within the environment. VLC performamce is affected by natural light restricting systems avilability and relibility. The paper presents an analysis of the performance of VLC systems under different meteorological conditions. The evaluation considered the impact of natural light as a function of different reflection surfaces in different room sizes.
Keywords: Visible light communication, impulse reponse , performance analysis , natural light.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17081422 Manufacture of Electroless Nickel/YSZ Composite Coatings
Authors: N. Bahiyah Baba, W. Waugh, A.M. Davidson
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The paper discusses optimising work on a method of processing ceramic / metal composite coatings for various applications and is based on preliminary work on processing anodes for solid oxide fuel cells (SOFCs). The composite coating is manufactured by the electroless co-deposition of nickel and yttria stabilised zirconia (YSZ) simultaneously on to a ceramic substrate. The effect on coating characteristics of substrate surface treatments and electroless nickel bath parameters such as pH and agitation methods are also investigated. Characterisation of the resulting deposit by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) is also discussed.
Keywords: Electroless deposition, nickel, YSZ, composite
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25691421 Inadequate Requirements Engineering Process: A Key Factor for Poor Software Development in Developing Nations: A Case Study
Authors: K. Adu Michael, K. Alese Boniface
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Developing a reliable and sustainable software products is today a big challenge among up–coming software developers in Nigeria. The inability to develop a comprehensive problem statement needed to execute proper requirements engineering process is missing. The need to describe the ‘what’ of a system in one document, written in a natural language is a major step in the overall process of Software Engineering. Requirements Engineering is a process use to discover, analyze and validate system requirements. This process is needed in reducing software errors at the early stage of the development of software. The importance of each of the steps in Requirements Engineering is clearly explained in the context of using detailed problem statement from client/customer to get an overview of an existing system along with expectations from the new system. This paper elicits inadequate Requirements Engineering principle as the major cause of poor software development in developing nations using a case study of final year computer science students of a tertiary-education institution in Nigeria.
Keywords: Client/Customer, Problem Statement, Requirements Engineering, Software Developers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24561420 Optimal Synthesis of Multipass Heat Exchanger without Resorting to Correction Factor
Authors: Bharat B. Gulyani, Anuj Jain, Shalendra Kumar
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Customarily, the LMTD correction factor, FT, is used to screen alternative designs for a heat exchanger. Designs with unacceptably low FT values are discarded. In this paper, authors have proposed a more fundamental criterion, based on feasibility of a multipass exchanger as the only criteria, followed by economic optimization. This criterion, coupled with asymptotic energy targets, provide the complete optimization space in a heat exchanger network (HEN), where cost-optimization of HEN can be performed with only Heat Recovery Approach temperature (HRAT) and number-of-shells as variables.Keywords: heat exchanger, heat exchanger networks, LMTD correction factor, shell targeting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 43241419 Detailed Phenomenological Study of 14N Elastically Scattered on 12C in a wide Energy Range
Authors: Sh. Hamada, N. Burtebayev, N. Amangeldi, A. Amar
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An experiment was performed with a 24.5 MeV 14N beam on a 12C target in the cyclotron DC-60 located in Astana, Kazakhstan, to study the elastic scattering of 14N on 12C; the scattering was also analyzed at different energies for tracking the phenomenon of remarkable structure at large angles. Its aims were to extend the measurements to very large angles, and attempt to uniquely identify the elastic scattering potential. Good agreement between the theoretical and experimental data has been obtained with suitable optical potential parameters. Optical model calculations with l -dependent imaginary potentials were also applied to the data and relatively good agreement was found.Keywords: Optical Potential Codes, Elastic Scattering, SPIVALCode.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15631418 Exergy Analysis of a Cogeneration Plant
Authors: Derya Burcu Ozkan, Onur Kiziler, Duriye Bilge
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Cogeneration may be defined as a system which contains electricity production and regain of the thermo value of exhaust gases simultaneously. The examination is based on the data-s of an active cogeneration plant. This study, it is aimed to determine which component of the system should be revised first to raise the efficiency and decrease the loss of exergy. For this purpose, second law analysis of thermodynamics is applied to each component due to consider the effects of environmental conditions and take the quality of energy into consideration as well as the quantity of it. The exergy balance equations are produced and exergy loss is calculated for each component. 44,44 % loss of exergy in heat exchanger, 29,59 % in combustion chamber, 18,68 % in steam boiler, 5,25 % in gas turbine and 2,03 % in compressor is calculated.Keywords: Cogeneration, Exergy loss, Second law analysis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25171417 Friction Stir Welding Process: A Green Technology
Authors: Esther T. Akinlabi, Stephen A. Akinlabi
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Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in the United Kingdom in 1991 for butt and lap welding of metals and plastics. This paper highlights the benefits of friction stir welding process as an energy efficient and a green technology process in the field of welding. Compared to the other conventional welding processes, its benefits, typical applications and its use in joining similar and dissimilar materials are also presented.Keywords: Dissimilar materials, Friction Stir Welding, Green technology, similar materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 49151416 The Effect of Chemical Treatment on TL Glow Curves of CdS/ZnS Thin Films Deposited by Vacuum Deposition Method
Authors: N. Dahbi, D-E. Arafah
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The effect of chemical treatment in CdCl2 and thermal annealing in 400°C, on the defect structures of potentially useful ZnS\CdS solar cell thin films deposited onto quartz substrate and prepared by vacuum deposition method was studied using the Thermoluminesence (TL) techniques. A series of electron and hole traps are found in the various deposited samples studied. After annealing, however, it was observed that the intensity and activation energy of TL signal increases with loss of the low temperature electron traps.Keywords: CdS, chemical treatment, heat treatment, Thermoluminescence, trapping parameters, thin film, vacuumdeposition, ZnS
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15231415 Calculation of Wave Function at the Origin (WFO) for Heavy Mesons by Numerical Solving of the Schrodinger Equation
Authors: M. Momeni Feyli
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Many recent high energy physics calculations involving charm and beauty invoke wave function at the origin (WFO) for the meson bound state. Uncertainties of charm and beauty quark masses and different models for potentials governing these bound states require a simple numerical algorithm for evaluation of the WFO's for these bound states. We present a simple algorithm for this propose which provides WFO's with high precision compared with similar ones already obtained in the literature.Keywords: Mesons, Bound states, Schrodinger equation, Nonrelativistic quark model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15031414 Sustainability through Self-Restriction: Livelihood Strategies of Urban Households in Kazakhstan
Authors: Daurenbek Kuleimenov
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Urban life is characterized by rapid changes and high influence of market institutions on livelihood strategies of households to get sustainability, especially in countries of former Soviet Union challenged transformation of economy to the market type. Moving from socialistic worldviews to capitalistic ones which as usual regulated by free markets has been enough big challenge for households in urban area, which have to face with adaptation to new systems. Influence of market institutions on everyday life and planning system of households can destroy traditional household dispositions of the sustainable managing of a family budget. New changes of economy system can lead to splitting up large social networks and appearing new risky livelihood strategies of households. Urban households from Astana that is the capital city of Kazakhstan were interviewed within international research project “Livelihoods Strategies of Private Households in Central Asia. A Rural-Urban Comparison in Kazakhstan and Kyrgyzstan”, which enables to explore urgent issues of livelihood strategies of urban households in current Kazakhstan under influence of the spreading of market institutions from the micro level research focus of their everyday life.
Keywords: Market institutions, Sustainability, Transformation economy, Urban households.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18491413 Reconsidering the Palaeo-Environmental Reconstruction of the Wet Zone of Sri Lanka: A Zooarchaeological Perspective
Authors: Kalangi Rodrigo, Kelum Manamendra-Arachchi
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Bones, teeth, and shells have been acknowledged over the last two centuries as evidence of chronology, Palaeo-environment, and human activity. Faunal traces are valid evidence of past situations because they have properties that have not changed over long periods. Sri Lanka has been known as an Island, which has a diverse variety of prehistoric occupation among ecological zones. Defining the Paleoecology of the past societies has been an archaeological thought developed in the 1960s. It is mainly concerned with the reconstruction from available geological and biological evidence of past biota, populations, communities, landscapes, environments, and ecosystems. This early and persistent human fossil, technical, and cultural florescence, as well as a collection of well-preserved tropical-forest rock shelters with associated 'on-site ' Palaeoenvironmental records, makes Sri Lanka a central and unusual case study to determine the extent and strength of early human tropical forest encounters. Excavations carried out in prehistoric caves in the low country wet zone has shown that in the last 50,000 years, the temperature in the lowland rainforests has not exceeded 5 degrees. Based on Semnopithecus Priam (Gray Langur) remains unearthed from wet zone prehistoric caves, it has been argued periods of momentous climate changes during the Last Glacial Maximum (LGM) and Terminal Pleistocene/Early Holocene boundary, with a recognizable preference for semi-open ‘Intermediate’ rainforest or edges. Continuous genus Acavus and Oligospira occupation along with uninterrupted horizontal pervasive of Canarium sp. (‘kekuna’ nut) have proven that temperatures in the lowland rain forests have not changed by at least 5 °C over the last 50,000 years. Site catchment or territorial analysis cannot be any longer defensible, due to time-distance based factors as well as optimal foraging theory failed as a consequence of prehistoric people were aware of the decrease in cost-benefit ratio and located sites, and generally played out a settlement strategy that minimized the ratio of energy expended to energy produced.Keywords: Palaeo-environment, palaeo-ecology, palaeo-climate, prehistory, zooarchaeology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7401412 Starting Torque Study of Darrieus Wind Turbine
Authors: M. Douak, Z. Aouachria
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The aim of our study is to project an optimized wind turbine of Darrieus type. This type of wind turbine is characterized by a low starting torque in comparison with the Savonius rotor allowing them to operate for a period greater than wind speed. This led us to reconsider the Darrieus rotor to optimize a design which will increase its starting torque. The study of a system of monitoring and control of the angle of attack of blade profile, which allows an auto start to wind speeds as low as possible is presented for the straight blade of Darrieus turbine. The study continues to extend to other configurations namely those of parabolic type.
Keywords: Darrieus turbine, pitch angle, self-stating, wind energy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46621411 Quantum Computation using Two Component Bose-Einstein Condensates
Authors: Tim Byrnes
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Quantum computation using qubits made of two component Bose-Einstein condensates (BECs) is analyzed. We construct a general framework for quantum algorithms to be executed using the collective states of the BECs. The use of BECs allows for an increase of energy scales via bosonic enhancement, resulting in two qubit gate operations that can be performed at a time reduced by a factor of N, where N is the number of bosons per qubit. We illustrate the scheme by an application to Deutsch-s and Grover-s algorithms, and discuss possible experimental implementations. Decoherence effects are analyzed under both general conditions and for the experimental implementation proposed.
Keywords: Quantum, computing, information, Bose-Einstein condensates, macroscopic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19781410 Farming Production in Brazil: Innovation and Land-Sparing Effect
Authors: Isabela Romanha de Alcantara, José Eustáquio Ribeiro Vieira Filho, José Garcia Gasques
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Innovation and technology can be determinant factors to ensure agricultural and sustainable growth, as well as productivity gains. Technical change has contributed considerably to supply agricultural expansion in Brazil. This agricultural growth could be achieved by incorporating more land or capital. If capital is the main source of agricultural growth, it is possible to increase production per unit of land. The objective of this paper is to estimate: 1) total factor productivity (TFP), which is measured in terms of the rate of output per unit of input; and 2) the land-saving effect (LSE) that is the amount of land required in the case that yield rate is constant over time. According to this study, from 1990 to 2019, it appears that 87% of Brazilian agriculture product growth comes from the gains of productivity; the remaining 13% comes from input growth. In the same period, the total LSE was roughly 400 Mha, which corresponds to 47% of the national territory. These effects reflect the greater efficiency of using productive factors, whose technical change has allowed an increase in the agricultural production based on productivity gains.
Keywords: agriculture, land-saving effect, livestock, productivity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7931409 Performance Monitoring of the Refrigeration System with Minimum Set of Sensors
Authors: Radek Fisera, Petr Stluka
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This paper describes a methodology for remote performance monitoring of retail refrigeration systems. The proposed framework starts with monitoring of the whole refrigeration circuit which allows detecting deviations from expected behavior caused by various faults and degradations. The subsequent diagnostics methods drill down deeper in the equipment hierarchy to more specifically determine root causes. An important feature of the proposed concept is that it does not require any additional sensors, and thus, the performance monitoring solution can be deployed at a low installation cost. Moreover only a minimum of contextual information is required, which also substantially reduces time and cost of the deployment process.Keywords: Condition monitoring, energy baselining, fault detection and diagnostics, commercial refrigeration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28801408 Microstructural Properties of the Interfacial Transition Zone and Strength Development of Concrete Incorporating Recycled Concrete Aggregate
Authors: S. Boudali, A. M. Soliman, B. Abdulsalam, K. Ayed, D. E. Kerdal, S. Poncet
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This study investigates the potential of using crushed concrete as aggregates to produce green and sustainable concrete. Crushed concrete was sieved to powder fine recycled aggregate (PFRA) less than 80 µm and coarse recycled aggregates (CRA). Physical, mechanical, and microstructural properties for PFRA and CRA were evaluated. The effect of the additional rates of PFRA and CRA on strength development of recycled aggregate concrete (RAC) was investigated. Additionally, the characteristics of interfacial transition zone (ITZ) between cement paste and recycled aggregate were also examined. Results show that concrete mixtures made with 100% of CRA and 40% PFRA exhibited similar performance to that of the control mixture prepared with 100% natural aggregate (NA) and 40% natural pozzolan (NP). Moreover, concrete mixture incorporating recycled aggregate exhibited a slightly higher later compressive strength than that of the concrete with NA. This was confirmed by the very dense microstructure for concrete mixture incorporating recycled concrete aggregates compared to that of conventional concrete mixture.
Keywords: Compressive strength, recycled concrete aggregates, microstructure, interfacial transition zone, powder fine recycled aggregate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12391407 Numerical Simulation of Electric and Hydrodynamic Fields Distribution in a Dielectric Liquids Electrofilter Cell
Authors: Narcis C. Ostahie, Tudor Sajin
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In this paper a numerical simulation of electric and hydrodynamic fields distribution in an electrofilter for dielectric liquids cell is made. The simulation is made with the purpose to determine the trajectory of particles that moves under the action of external force in an electric and hydrodynamic field created inside of an electrofilter for dielectric liquids. Particle trajectory is analyzed for a dielectric liquid-solid particles suspension.Keywords: Dielectric liquids, electrohydrodynamics, energy, high voltage, particles
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16141406 Numerical Study on Improving Indoor Thermal Comfort Using a PCM Wall
Authors: M. Faraji, F. Berroug
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A one-dimensional mathematical model was developed in order to analyze and optimize the latent heat storage wall. The governing equations for energy transport were developed by using the enthalpy method and discretized with volume control scheme. The resulting algebraic equations were next solved iteratively by using TDMA algorithm. A series of numerical investigations were conducted in order to examine the effects of the thickness of the PCM layer on the thermal behavior of the proposed heating system. Results are obtained for thermal gain and temperature fluctuation. The charging discharging process was also presented and analyzed.
Keywords: Phase change material, Building, Concrete, Latent heat, Thermal control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21451405 The Application of Homotopy Method In Solving Electrical Circuit Design Problem
Authors: Talib Hashim Hasan
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This paper describes simple implementation of homotopy (also called continuation) algorithm for determining the proper resistance of the resistor to dissipate energy at a specified rate of an electric circuit. Homotopy algorithm can be considered as a developing of the classical methods in numerical computing such as Newton-Raphson and fixed point methods. In homoptopy methods, an embedding parameter is used to control the convergence. The method purposed in this work utilizes a special homotopy called Newton homotopy. Numerical example solved in MATLAB is given to show the effectiveness of the purposed methodKeywords: electrical circuit homotopy, methods, MATLAB, Newton homotopy
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30311404 Electron Density Discrepancy Analysis of Energy Metabolism Coenzymes
Authors: Alan Luo, Hunter N. B. Moseley
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Many macromolecular structure entries in the Protein Data Bank (PDB) have a range of regional (localized) quality issues, be it derived from X-ray crystallography, Nuclear Magnetic Resonance (NMR) spectroscopy, or other experimental approaches. However, most PDB entries are judged by global quality metrics like R-factor, R-free, and resolution for X-ray crystallography or backbone phi-psi distribution statistics and average restraint violations for NMR. Regional quality is often ignored when PDB entries are re-used for a variety of structurally based analyses. The binding of ligands, especially ligands involved in energy metabolism, is of particular interest in many structurally focused protein studies. Using a regional quality metric that provides chemically interpretable information from electron density maps, a significant number of outliers in regional structural quality was detected across X-ray crystallographic PDB entries for proteins bound to biochemically critical ligands. In this study, a series of analyses was performed to evaluate both specific and general potential factors that could promote these outliers. In particular, these potential factors were the minimum distance to a metal ion, the minimum distance to a crystal contact, and the isotropic atomic b-factor. To evaluate these potential factors, Fisher’s exact tests were performed, using regional quality criteria of outlier (top 1%, 2.5%, 5%, or 10%) versus non-outlier compared to a potential factor metric above versus below a certain outlier cutoff. The results revealed a consistent general effect from region-specific normalized b-factors but no specific effect from metal ion contact distances and only a very weak effect from crystal contact distance as compared to the b-factor results. These findings indicate that no single specific potential factor explains a majority of the outlier ligand-bound regions, implying that human error is likely as important as these other factors. Thus, all factors, including human error, should be considered when regions of low structural quality are detected. Also, the downstream re-use of protein structures for studying ligand-bound conformations should screen the regional quality of the binding sites. Doing so prevents misinterpretation due to the presence of structural uncertainty or flaws in regions of interest.
Keywords: Biomacromolecular structure, coenzyme, electron density discrepancy analysis, X-ray crystallography.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2551403 Interface Location in Single Phase Stirred Tanks
Authors: I. Mahdavi, R. Janamiri, A. Sinkakarimi, M. Safdari, M. H. Sedaghat, A. Zamani, A. Hoseini, M. Karimi
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In this work, study the location of interface in a stirred vessel with Rushton impeller by computational fluid dynamic was presented. To modeling rotating the impeller, sliding mesh (SM) technique was used and standard k-ε model was selected for turbulence closure. Mean tangential, radial and axial velocities and also turbulent kinetic energy (k) and turbulent dissipation rate (ε) in various points of tank was investigated. Results show sensitivity of system to location of interface and radius of 7 to 10cm for interface in the vessel with existence characteristics cause to increase the accuracy of simulation.
Keywords: CFD, Interface, Rushton impeller, Turbulence model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17251402 Stability of Electrical Drives Supplied by a Three Level Inverter
Authors: M. S. Kelaiaia, H. Labar, S. Kelaiaia, T. Mesbah
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The development of the power electronics has allowed increasing the precision and reliability of the electrical devices, thanks to the adjustable inverters, as the Pulse Wide Modulation (PWM) applied to the three level inverters, which is the object of this study. The authors treat the relation between the law order adopted for a given system and the oscillations of the electrical and mechanical parameters of which the tolerance depends on the process with which they are integrated (paper factory, lifting of the heavy loads, etc.).Thus, the best choice of the regulation indexes allows us to achieve stability and safety training without investment (management of existing equipment). The optimal behavior of any electric device can be achieved by the minimization of the stored electrical and mechanical energy.Keywords: Multi level inverter, PWM, Harmonics, oscillation, control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13731401 Bearing Condition Monitoring with Acoustic Emission Techniques
Authors: Faisal AlShammari, Abdulmajid Addali
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Monitoring the conditions of rotating machinery, such as bearings, is important in order to improve the stability of work. Acoustic Emission (AE) and vibration analysis are some of the most accomplished techniques used for this purpose. Acoustic emission has the ability to detect the initial phase of component degradation. Moreover, it has been observed that vibration analysis is not as successful at low rotational speeds (below 100 rpm). This because the energy generated within this speed region is not detectable using conventional vibration. From this perspective, this paper has presented a brief review of using acoustic emission techniques for monitoring bearing conditions.
Keywords: Condition monitoring, stress wave analysis, low-speed bearings, bearing defect diagnosis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38011400 Calculation of Heating Load for an Apartment Complex with Unit Building Method
Authors: Ju-Seok Kim, Sun-Ae Moon, Tae-Gu Lee, Seung-Jae Moon, Jae-Heon Lee
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As a simple to method estimate the plant heating energy capacity of an apartment complex, a new load calculation method has been proposed. The method which can be called as unit building method, predicts the heating load of the entire complex instead of summing up that of each apartment belonging to complex. Comparison of the unit heating load for various floor sizes between the present method and conventional approach shows a close agreement with dynamic load calculation code. Some additional calculations are performed to demonstrate it-s application examples.Keywords: Unit Building Method, Unit Heating Load, TFMLoad.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 34391399 Numerical Simulation of High Pressure Hydrogen Emerges to Air
Authors: Mohamed H. Elhsnawi, Mesbah M. Salem, Saleh B. Mohamed
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Numerical simulation performed to investigate the behavior of the high pressure hydrogen jetting of air. High pressure hydrogen (30–40 MPa) was injected to air at atmospheric pressure through 2mm orifice. Numerical simulations were performed with Kiva3V code with 2D axisymmetric geometry. Numerical simulations showed that auto ignition of high pressure hydrogen to air are possible due to molecular diffusion. Auto ignition was predicted at hydrogen-air contact surface due to mass and energy exchange between high temperature hydrogen and air heated by shock wave.
Keywords: Spontaneous Ignition, Diffusion Ignition, Hydrogen ignition, Hydrogen Jet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19071398 Pioneer Synthesis and Characterization of Boron Containing Hard Materials
Authors: G. Çelik Gül, F. Kurtuluş
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The first laboratory synthesis of hard materials such as diamond proceeded to attack of developing materials with high hardness to compete diamond. Boron rich solids are good candidates owing to their short interatomic bond lengths and strong covalent character. Boron containing hard material was synthesized by modifiedmicrowave method under nitrogen atmosphere by using a fuel (glycine or urea), amorphous boron and/or boric acid in appropriate molar ratio. Characterizations were done by x-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS), thermo gravimetric/differential thermal analysis (TG/DTA).Keywords: Boron containing materials, hard materials, microwave synthesis, powder X-ray diffraction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21821397 High-Production Laser and Plasma Welding Technologies for High-Speed Vessels Production
Authors: V. M. Levshakov, N. A. Steshenkova, N. A. Nosyrev
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Application of hulls processing technologies, based on high-concentrated energy sources (laser and plasma technologies), allow improve shipbuilding production. It is typical for high-speed vessels construction using steel and aluminum alloys with high precision hulls required. Report describes high-performance technologies for plasma welding (using direct current of reversed polarity), laser, and hybrid laser-arc welding of hulls structures developed by JSC “SSTC”
Keywords: Flat sections, hybrid laser-arc welding, plasma welding, plasmatron.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25991396 Wear and Mechanical Properties of Nodular Iron Modified with Copper
Authors: J. Ramos, V. Gil, A. F. Torres
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In this research (using induction furnace process) nodular iron with three different percentages of copper (residual, 0.5% and 1,2%) was obtained. Chemical analysis was performed by mass spectrometry and microstructures were characterized by Optical Microscopy (ASTM E3) and Scanning Electron Microscopy (SEM). The study of mechanical behavior was carried out in a mechanical test machine (ASTM E8) and a Pin on disk tribometer (ASTM G99) was used to assess wear resistance. It is observed that the dissolution of copper in crystal lattice increases the pearlite structure improving the wear and hardness behavior, but producing a contrary effect on the energy absorption.
Keywords: Ferritic and perlite structure, mechanical properties, nodular iron, wear.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22691395 TACS : Thermo Acoustic Cooling System
Authors: Z. Zarid, C. Gamba, A. Brusseaux, C. Laborie, K. Briens
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Cooling with sound is a physical phenomenon allowed by Thermo-Acoustics in which acoustic energy is transformed into a negative heat transfer, in other words: into cooling! Without needing any harmful gas, the transformation is environmentally friendly and can respond to many needs in terms of air conditioning, food refrigeration for domestic use, and cooling medical samples for example. To explore the possibilities of this cooling solution on a small scale, the TACS prototype has been designed, consisting of a low cost thermoacoustic refrigerant “pipe” able to lower the temperature by a few degrees. The obtained results are providing an interesting element for possible future of thermo-acoustic refrigeration.Keywords: Domestic Scale Cooling System, Thermoacoustic, Environmental Friendly Refrigeration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24371394 Design the Bowtie Antenna for the Detection of the Tumor in Microwave Tomography
Authors: Muhammd Hassan Khalil, Xu Jiadong
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Early breast cancer detection is an emerging field of research as it can save the women infected by malignant tumors. Microwave breast imaging is based on the electrical property contrast between healthy and malignant tumor. This contrast can be detected by use of microwave energy with an array of antennas that illuminate the breast through coupling medium and by measuring the scattered fields. In this paper, author has been presented the design and simulation results of the bowtie antenna. This bowtie antenna is designed for the detection of breast cancer detection.
Keywords: Breast cancer detection, Microwave Imaging, Tomography.
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