Search results for: soil temperature.
513 Development of Map of Gridded Basin Flash Flood Potential Index: GBFFPI Map of QuangNam, QuangNgai, DaNang, Hue Provinces
Authors: Le Xuan Cau
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Flash flood is occurred in short time rainfall interval: from 1 hour to 12 hours in small and medium basins. Flash floods typically have two characteristics: large water flow and big flow velocity. Flash flood is occurred at hill valley site (strip of lowland of terrain) in a catchment with large enough distribution area, steep basin slope, and heavy rainfall. The risk of flash floods is determined through Gridded Basin Flash Flood Potential Index (GBFFPI). Flash Flood Potential Index (FFPI) is determined through terrain slope flash flood index, soil erosion flash flood index, land cover flash floods index, land use flash flood index, rainfall flash flood index. Determining GBFFPI, each cell in a map can be considered as outlet of a water accumulation basin. GBFFPI of the cell is determined as basin average value of FFPI of the corresponding water accumulation basin. Based on GIS, a tool is developed to compute GBFFPI using ArcObjects SDK for .NET. The maps of GBFFPI are built in two types: GBFFPI including rainfall flash flood index (real time flash flood warning) or GBFFPI excluding rainfall flash flood index. GBFFPI Tool can be used to determine a high flash flood potential site in a large region as quick as possible. The GBFFPI is improved from conventional FFPI. The advantage of GBFFPI is that GBFFPI is taking into account the basin response (interaction of cells) and determines more true flash flood site (strip of lowland of terrain) while conventional FFPI is taking into account single cell and does not consider the interaction between cells. The GBFFPI Map of QuangNam, QuangNgai, DaNang, Hue is built and exported to Google Earth. The obtained map proves scientific basis of GBFFPI.Keywords: ArcObjects SDK for .NET, Basin average value of FFPI, Gridded basin flash flood potential index, GBFFPI map.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1909512 Bond Graph Modeling of Mechanical Dynamics of an Excavator for Hydraulic System Analysis and Design
Authors: Mutuku Muvengei, John Kihiu
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This paper focuses on the development of bond graph dynamic model of the mechanical dynamics of an excavating mechanism previously designed to be used with small tractors, which are fabricated in the Engineering Workshops of Jomo Kenyatta University of Agriculture and Technology. To develop a mechanical dynamics model of the manipulator, forward recursive equations similar to those applied in iterative Newton-Euler method were used to obtain kinematic relationships between the time rates of joint variables and the generalized cartesian velocities for the centroids of the links. Representing the obtained kinematic relationships in bondgraphic form, while considering the link weights and momenta as the elements led to a detailed bond graph model of the manipulator. The bond graph method was found to reduce significantly the number of recursive computations performed on a 3 DOF manipulator for a mechanical dynamic model to result, hence indicating that bond graph method is more computationally efficient than the Newton-Euler method in developing dynamic models of 3 DOF planar manipulators. The model was verified by comparing the joint torque expressions of a two link planar manipulator to those obtained using Newton- Euler and Lagrangian methods as analyzed in robotic textbooks. The expressions were found to agree indicating that the model captures the aspects of rigid body dynamics of the manipulator. Based on the model developed, actuator sizing and valve sizing methodologies were developed and used to obtain the optimal sizes of the pistons and spool valve ports respectively. It was found that using the pump with the sized flow rate capacity, the engine of the tractor is able to power the excavating mechanism in digging a sandy-loom soil.Keywords: Actuators, bond graphs, inverse dynamics, recursive equations, quintic polynomial trajectory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2882511 Pressure Swing Adsorption with Cassava Adsorbent for Dehydration of Ethanol Vapor
Authors: Chontira Boonfung, Panarat Rattanaphanee
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Ethanol has become more attractive in fuel industry either as fuel itself or an additive that helps enhancing the octane number and combustibility of gasoline. This research studied a pressure swing adsorption using cassava-based adsorbent prepared from mixture of cassava starch and cassava pulp for dehydration of ethanol vapor. The apparatus used in the experiments consisted of double adsorption columns, an evaporator, and a vacuum pump. The feed solution contained 90-92 %wt of ethanol. Three process variables: adsorption temperatures (110, 120 and 130°C), adsorption pressures (1 and 2 bar gauge) and feed vapor flow rate (25, 50 and 75 % valve opening of the evaporator) were investigated. According to the experimental results, the optimal operating condition for this system was found to be at 2 bar gauge for adsorption pressure, 120°C for adsorption temperature and 25% valve opening of the evaporator. Production of 1.48 grams of ethanol with concentration higher than 99.5 wt% per gram of adsorbent was obtained. PSA with cassavabased adsorbent reported in this study could be an alternative method for production of nearly anhydrous ethanol. Dehydration of ethanol vapor achieved in this study is due to an interaction between free hydroxyl group on the glucose units of the starch and the water molecules.Keywords: Adsorption, PSA, Ethanol, Dehydration, Cassava.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2800510 Influence of Mass Flow Rate on Forced Convective Heat Transfer through a Nanofluid Filled Direct Absorption Solar Collector
Authors: Salma Parvin, M. A. Alim
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The convective and radiative heat transfer performance and entropy generation on forced convection through a direct absorption solar collector (DASC) is investigated numerically. Four different fluids, including Cu-water nanofluid, Al2O3-waternanofluid, TiO2-waternanofluid, and pure water are used as the working fluid. Entropy production has been taken into account in addition to the collector efficiency and heat transfer enhancement. Penalty finite element method with Galerkin’s weighted residual technique is used to solve the governing non-linear partial differential equations. Numerical simulations are performed for the variation of mass flow rate. The outcomes are presented in the form of isotherms, average output temperature, the average Nusselt number, collector efficiency, average entropy generation, and Bejan number. The results present that the rate of heat transfer and collector efficiency enhance significantly for raising the values of m up to a certain range.Keywords: DASC, forced convection, mass flow rate, nanofluid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 849509 Optimization of Diluted Organic Acid Pretreatment on Rice Straw Using Response Surface Methodology
Authors: Rotchanaphan Hengaroonprasan, Malinee Sriariyanun, Prapakorn Tantayotai, Supacharee Roddecha, Kraipat Cheenkachorn
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Lignocellolusic material is a substance that is resistant to be degraded by microorganisms or hydrolysis enzymes. To be used as materials for biofuel production, it needs pretreatment process to improve efficiency of hydrolysis. In this work, chemical pretreatments on rice straw using three diluted organic acids, including acetic acid, citric acid, oxalic acid, were optimized. Using Response Surface Methodology (RSM), the effect of three pretreatment parameters, acid concentration, treatment time, and reaction temperature, on pretreatment efficiency were statistically evaluated. The results indicated that dilute oxalic acid pretreatment led to the highest enhancement of enzymatic saccharification by commercial cellulase and yielded sugar up to 10.67 mg/ml when using 5.04% oxalic acid at 137.11 oC for 30.01 min. Compared to other acid pretreatment by acetic acid, citric acid, and hydrochloric acid, the maximum sugar yields are 7.07, 6.30, and 8.53 mg/ml, respectively. Here, it was demonstrated that organic acids can be used for pretreatment of lignocellulosic materials to enhance of hydrolysis process, which could be integrated to other applications for various biorefinery processes.
Keywords: Lignocellolusic biomass, pretreatment, organic acid response surface methodology, biorefinery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2391508 Decomposing the Impact Factors of Energy Consumption of Hotel through LMDI
Authors: Zongjie Du, Shulin Sui, Panpan Xu
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Energy consumption of a hotel can be a hot topic in smart city; it is difficult to evaluate the contribution of impact factors to energy consumption of a hotel. Therefore, grasping the key impact factors has great effect on the energy saving management of a hotel. Based on the SPIRTPAT model, we establish the identity with the impact factors of occupancy rate, unit area of revenue, temperature factor, unit revenue of energy consumption. In this paper, we use the LMDI (Logarithmic Mean Divisia Index) to decompose the impact factors of energy consumption of hotel from Jan. to Dec. in 2001. The results indicate that the occupancy rate and unit area of revenue are the main factors that can increase unit area of energy consumption, and the unit revenue of energy consumption is the main factor to restrain the growth of unit area of energy consumption. When the energy consumption of hotel can appear abnormal, the hotel manager can carry out energy saving management and control according to the contribution value of impact factors.Keywords: Smart city, SPIRTPAT model, LMDI, saving management and control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1396507 Experimental Analysis on Electrical and Photometric Performances of Commercially Available Integrated Compact Fluorescent Lamp
Authors: Hu-Hsiao Hsu, Po-Ren Chung, Ming-Chin Ho, Chieh-Feng Tsai, Che-Ming Chiang, Shin-Ku Lee
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Lighting upgrades involve relatively lower costs which allow the benefits to be spread more widely than is possible with any other energy efficiency measure. In order to popularize the adoption of CFL in Taiwan, the authority proposes to implement a new energy efficient lamp comparative label system. The current study was accordingly undertaken to investigate the factors affecting the performance and the deviation of actual and labeled performance of commercially available integrated CFLs. In this paper, standard test methods to determine the electrical and photometric performances of CFL were developed based on CIE 84-1989 and CIE 60901-1987, then 55 selected CFLs from market were tested. The results show that with higher color temperature of CFLs lower efficacy are achieved. It was noticed that the most packaging of CFL often lack the information of Color Rendering Index. Also, there was no correlation between price and performance of the CFLs was indicated in this work. The results of this paper might help consumers to make more informed CFL-purchasing decisions.Keywords: Compact fluorescent lamp (CFL), Efficacy, Color Rendering Index (CRI), Energy saving.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1494506 Advanced Materials Based on Ethylene-Propylene-Diene Terpolymers and Organically Modified Montmorillonite
Authors: M. D. Stelescu, E. Manaila, G. Pelin, M. Georgescu, M. Sonmez
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This paper presents studies on the development and characterization of nanocomposites based on ethylene-propylene terpolymer rubber (EPDM), chlorobutyl rubber (IIR-Cl) and organically modified montmorillonite (OMMT). Mixtures were made containing 0, 3 and 6 phr (parts per 100 parts rubber) OMMT, respectively. They were obtained by melt intercalation in an internal mixer - Plasti-Corder Brabender, in suitable blending parameters, at high temperature for 11 minutes. Curing agents were embedded on a laboratory roller at 70-100 ºC, friction 1:1.1, processing time 5 minutes. Rubber specimens were obtained by compression, using a hydraulic press at 165 ºC and a pressing force of 300 kN. Curing time, determined using the Monsanto rheometer, decreases with the increased amount of OMMT in the mixtures. At the same time, it was noticed that mixtures containing OMMT show improvement in physical-mechanical properties. These types of nanocomposites may be used to obtain rubber seals for the space application or for other areas of application.
Keywords: Chlorobutyl rubber, ethylene-propylene-diene terpolymers, montmorillonite, rubber seals, space application.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 715505 Using Non-Linear Programming Techniques in Determination of the Most Probable Slip Surface in 3D Slopes
Authors: M. M. Toufigh, A. R. Ahangarasr, A. Ouria
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Among many different methods that are used for optimizing different engineering problems mathematical (numerical) optimization techniques are very important because they can easily be used and are consistent with most of engineering problems. Many studies and researches are done on stability analysis of three dimensional (3D) slopes and the relating probable slip surfaces and determination of factors of safety, but in most of them force equilibrium equations, as in simplified 2D methods, are considered only in two directions. In other words for decreasing mathematical calculations and also for simplifying purposes the force equilibrium equation in 3rd direction is omitted. This point is considered in just a few numbers of previous studies and most of them have only given a factor of safety and they haven-t made enough effort to find the most probable slip surface. In this study shapes of the slip surfaces are modeled, and safety factors are calculated considering the force equilibrium equations in all three directions, and also the moment equilibrium equation is satisfied in the slip direction, and using nonlinear programming techniques the shape of the most probable slip surface is determined. The model which is used in this study is a 3D model that is composed of three upper surfaces which can cover all defined and probable slip surfaces. In this research the meshing process is done in a way that all elements are prismatic with quadrilateral cross sections, and the safety factor is defined on this quadrilateral surface in the base of the element which is a part of the whole slip surface. The method that is used in this study to find the most probable slip surface is the non-linear programming method in which the objective function that must get optimized is the factor of safety that is a function of the soil properties and the coordinates of the nodes on the probable slip surface. The main reason for using non-linear programming method in this research is its quick convergence to the desired responses. The final results show a good compatibility with the previously used classical and 2D methods and also show a reasonable convergence speed.Keywords: Non-linear programming, numerical optimization, slope stability, 3D analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1605504 Optimum Design of Alkali Activated Slag Concretes for Low Chloride Ion Permeability and Water Absorption Capacity
Authors: Müzeyyen Balçikanli, Erdoğan Özbay, Hakan Tacettin Türker, Okan Karahan, Cengiz Duran Atiş
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In this research, effect of curing time (TC), curing temperature (CT), sodium concentration (SC) and silicate modules (SM) on the compressive strength, chloride ion permeability, and water absorption capacity of alkali activated slag (AAS) concretes were investigated. For maximization of compressive strength while for minimization of chloride ion permeability and water absorption capacity of AAS concretes, best possible combination of CT, CTime, SC and SM were determined. An experimental program was conducted by using the central composite design method. Alkali solution-slag ratio was kept constant at 0.53 in all mixture. The effects of the independent parameters were characterized and analyzed by using statistically significant quadratic regression models on the measured properties (dependent parameters). The proposed regression models are valid for AAS concretes with the SC from 0.1% to 7.5%, SM from 0.4 to 3.2, CT from 20 °C to 94 °C and TC from 1.2 hours to 25 hours. The results of test and analysis indicate that the most effective parameter for the compressive strength, chloride ion permeability and water absorption capacity is the sodium concentration.
Keywords: Alkali activation, slag, rapid chloride permeability, water absorption capacity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1134503 Preconcentration and Determination of Cyproheptadine in Biological Samples by Hollow Fiber Liquid Phase Microextraction Coupled with High Performance Liquid Chromatography
Authors: Najari Moghadam Sh., Qomi M., Raofie F., Khadiv J.
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In this study, a liquid phase microextraction by hollow fiber (HF-LPME) combined with high performance liquid chromatography-UV detector was applied to preconcentrate and determine trace levels of Cyproheptadine in human urine and plasma samples. Cyproheptadine was extracted from 10 mL alkaline aqueous solution (pH: 9.81) into an organic solvent (n-octnol) which was immobilized in the wall pores of a hollow fiber. Then was back-extracted into an acidified aqueous solution (pH: 2.59) located inside the lumen of the hollow fiber. This method is simple, efficient and cost-effective. It is based on pH gradient and differences between two aqueous phases. In order to optimize the HF-LPME some affecting parameters including the pH of donor and acceptor phases, the type of organic solvent, ionic strength, stirring rate, extraction time and temperature were studied and optimized. Under optimal conditions enrichment factor, limit of detection (LOD) and relative standard deviation (RSD(%), n=3) were up to 112, 15 μg.L−1 and 2.7, respectively.
Keywords: Biological samples, Cyproheptadine, hollow fiber, liquid phase microextraction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2224502 Structural Health Monitoring of Buildings and Infrastructure
Authors: Mojtaba Valinejadshoubi, Ashutosh Bagchi, Osama Moselhi
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Structures such as buildings, bridges, dams, wind turbines etc. need to be maintained against various factors such as deterioration, excessive loads, environment, temperature, etc. Choosing an appropriate monitoring system is important for determining any critical damage to a structure and address that to avoid any adverse consequence. Structural Health Monitoring (SHM) has emerged as an effective technique to monitor the health of the structures. SHM refers to an ongoing structural performance assessment using different kinds of sensors attached to or embedded in the structures to evaluate their integrity and safety to help engineers decide on rehabilitation measures. Ability of SHM in identifying the location and severity of structural damages by considering any changes in characteristics of the structures such as their frequency, stiffness and mode shapes helps engineers to monitor the structures and take the most effective corrective actions to maintain their safety and extend their service life. The main objective of this study is to review the overall SHM process specifically determining the natural frequency of an instrumented simply-supported concrete beam using modal testing and finite element model updating.
Keywords: Structural Health Monitoring, Natural Frequency, FFT analysis, Finite element model updating.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2431501 Using Printing Method and Post Heat Treatment to Fabricate CIS Absorber Layer
Authors: Mao-An Chen, Chien-Chen Diao, Chia-Cheng Huang, Chin-Guo Kuo, Cheng-Fu Yang, Yen-Lin Chen
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In this study, the Mo-electrode thin films were deposited using two-stepped process and the high purity copper indium selenide-based powder (CuInSe2, CIS) was fabricated by using hydrothermal process by Nanowin Technology Co. Ltd. Because the CIS powder was aggregated into microscale particles, the CIS power was ground into nano-scale particles. 6 wt% CIS particles were mixed and dispersed into isopropyl alcohol (IPA). A new non-vacuum thin-film deposition process, spray coating method (SPM), was investigated to deposit the high-densified CIS absorber layers. 0.1 ml CIS solution was sprayed on the 20 mm×10 mm Mo/glass substrates and then the CuInSe2 thin films were annealed in a selenization furnace using N2 as atmosphere. The annealing temperature and time were set at 550oC and 5 min, and 0.0g~0.6g extra Se content was added in the furnace. The influences of extra Se content on the densification, crystallization, resistivity (ρ), hall mobility (μ), and carrier concentration of the CIS absorber layers were well investigated in this study.
Keywords: CuInSe2, isopropyl alcohol, spray coating method, annealing, selenization process.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2119500 CFD Study on the Effect of Primary Air on Combustion of Simulated MSW Process in the Fixed Bed
Authors: Rui Sun, Tamer M. Ismail, Xiaohan Ren, M. Abd El-Salam
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Incineration of municipal solid waste (MSW) is one of the key scopes in the global clean energy strategy. A computational fluid dynamics (CFD) model was established in order to reveal these features of the combustion process in a fixed porous bed of MSW. Transporting equations and process rate equations of the waste bed were modeled and set up to describe the incineration process, according to the local thermal conditions and waste property characters. Gas phase turbulence was modeled using k-ε turbulent model and the particle phase was modeled using the kinetic theory of granular flow. The heterogeneous reaction rates were determined using Arrhenius eddy dissipation and the Arrhenius-diffusion reaction rates. The effects of primary air flow rate and temperature in the burning process of simulated MSW are investigated experimentally and numerically. The simulation results in bed are accordant with experimental data well. The model provides detailed information on burning processes in the fixed bed, which is otherwise very difficult to obtain by conventional experimental techniques.
Keywords: Computational Fluid Dynamics (CFD) model, Waste Incineration, Municipal Solid Waste (MSW), Fixed Bed, Primary air.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2707499 Photocatalytic Degradation of Organic Pollutant Reacting with Tungstates: Role of Microstructure and Size Effect on Oxidation Kinetics
Authors: A. Taoufyq, B. Bakiz, A. Benlhachemi, L. Patout, D. V. Chokouadeua, F. Guinneton, G. Nolibe, A. Lyoussi, J-R. Gavarri
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The aim of this study was to investigate the photocatalytic activity of polycrystalline phases of bismuth tungstate of formula Bi2WO6. Polycrystalline samples were elaborated using a coprecipitation technique followed by a calcination process at different temperatures (300, 400, 600 and 900°C). The obtained polycrystalline phases have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Crystal cell parameters and cell volume depend on elaboration temperature. High-resolution electron microscopy images and image simulations, associated with X-ray diffraction data, allowed confirming the lattices and space groups Pca21. The photocatalytic activity of the as-prepared samples was studied by irradiating aqueous solutions of Rhodamine B, associated with Bi2WO6 additives having variable crystallite sizes. The photocatalytic activity of such bismuth tungstates increased as the crystallite sizes decreased. The high specific area of the photocatalytic particles obtained at 300°C seems to condition the degradation kinetics of RhB.Keywords: Bismuth tungstate, crystallite sizes, electron microscopy, photocatalytic activity, X-ray diffraction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2055498 Fracture Toughness Properties and FTIR Analysis of Corn Fiber Green Composites
Authors: Ahmed Mudhafar Hashim, Aseel Mahmood Abdullah
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The present work introduced a green composite consisting of corn natural fiber of constant concentration of 10% by weight incorporation with poly methyl methacrylate matrix biomaterial prepared by hand lay-up technique. Corn natural fibers were treated with two concentrations of sodium hydroxide solution (3% and 5%) with different immersed time (1.5 and 3 hours) at room temperature. The fracture toughness test of untreated and alkali treated corn fiber composites were performed. The effect of chemically treated on fracture properties of composites has been analyzed using Fourier transform infrared (FTIR) spectroscopy. The experimental results showed that the alkali treatment improved the fracture properties in terms of plane strain fracture toughness KIC. It was found that the plane strain fracture toughness KIC increased by up to 62% compared to untreated fiber composites. On the other hand, increases in both concentrations of alkali solution and time of soaking to 5% NaOH and 3 hours, respectively reduced the values of KIC lower than the value of the unfilled material.
Keywords: green composites, fracture toughness, corn natural fiber, Bio-PMMA
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 513497 Precipitation Change and its Implication in the Change of Winter Wheat drought and Production in North China Region from 2000 to 2010
Authors: Y. Huang, Q. J. Tian, L. T. Du, J. Liu, S. S. Li
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Understanding how precipitation inter-annually changes and its implication in agricultural drought and production change in winter wheat (Triticum aestivum L.) growth season is critical for crop production in China. MODIS Temperature-Vegetation Dryness Index (TVDI) and daily mean precipitation time series for the main growth season(Feb. to May) of winter wheat from 2000 to 2010 were used to analyze the distribution of trends of precipitation, agricultural drought and winter wheat yield change respectively, and relationships between them in North China region(Huang-huai-hai region, HHH region), China. The results indicated that the trend of precipitation in HHH region past 11 years was increasing, which had induced generally corresponding decreasing trend of agricultural drought and increasing trend of wheat yield, while the trend of drought was spatially diverse. The study could provide a basis for agricultural drought research during winter wheat season in HHH region under the ground of climate change.Keywords: drought, MODIS, precipitation change, TVDI, winter wheat production
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1632496 Phase Transition Characteristics of Flame-Synthesized Gamma-Al2O3 Nanoparticles with Heat Treatment
Authors: Gyo Woo Lee
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In this study, the phase transition characteristics of flame-synthesized γ-Al2O3 nanoparticles to α-Al2O3 have been investigated. The nanoparticles were synthesized by using a coflow hydrogen diffusion flame. The phase transition and particle characteristics of the Al2O3 nanoparticles were determined by examining the crystalline structure and the shape of the collected nanoparticles before and after the heat treatment. The morphology and crystal structure of the Al2O3 nanoparticles were determined from SEM images and XRD analyses, respectively. The measured specific surface area and averaged particle size were 63.44m2/g and 23.94nm, respectively. Based on the scanning electron microscope images and x-ray diffraction patterns, it is believed that the onset temperature of the phase transition to α-Al2O3 was existed near 1200oC. The averaged diameters of the sintered particles heat treated at 1,260oC were approximately 80nm.
Keywords: BET Specific Surface Area, Gamma-Al2O3 Nanoparticles, Flame Synthesis, Phase Transition, X-ray Diffraction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5016495 The Effect of Addition of Dioctyl Terephthalate and Calcite on the Tensile Properties of Organoclay/Linear Low Density Polyethylene Nanocomposites
Authors: A. Gürses, Z. Eroğlu, E. Şahin, K. Güneş, Ç. Doğar
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In recent years, polymer/clay nanocomposites have generated great interest in the polymer industry as a new type of composite material because of their superior properties, which includes high heat deflection temperature, gas barrier performance, dimensional stability, enhanced mechanical properties, optical clarity and flame retardancy when compared with the pure polymer or conventional composites. The investigation of change of the tensile properties of organoclay/linear low density polyethylene (LLDPE) nanocomposites with the use of Dioctyl terephthalate (DOTP) (as plasticizer) and calcite (as filler) has been aimed. The composites and organoclay synthesized were characterized using the techniques such as XRD, HRTEM and FTIR techniques. The spectroscopic results indicate that platelets of organoclay were well dispersed within the polymeric matrix. The tensile properties of the composites were compared considering the stress-strain curve drawn for each composite and pure polymer. It was observed that the composites prepared by adding the plasticizer at different ratios and a certain amount of calcite exhibited different tensile behaviors compared to pure polymer.
Keywords: Linear low density polyethylene, nanocomposite, organoclay, plasticizer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1433494 Influence of Electrolytes and High Viscosity on Liquid-Liquid Separation
Authors: K. Anusarn, P. Chuttrakul, M. Schmidt, T. Kangsadan, A. Pfennig
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Liquid-liquid extraction is a process using two immiscible liquids to extract compounds from one phase without high temperature requirement. Mostly, the technical implementation of this process is carried out in mixer-settlers or extraction columns. In real chemical processes, chemicals may have high viscosity and contain impurities. These impurities may change the settling behavior of the process without measurably changing the physical properties of the phases. In the current study, the settling behavior and the affected parameters in a high-viscosity system were observed. Batchsettling experiments were performed to experimentally quantify the settling behavior and the mixer-settler model of Henschke [1] was used to evaluate the behavior of the toluene + water system. The viscosity of the system was increased by adding polyethylene glycol 4000 to the aqueous phase. NaCl and Na2SO4 were used to study the influence of electrolytes. The results from this study show that increasing the viscosity of water has a higher influence on the settling behavior in comparison to the effects of the electrolytes. It can be seen from the experiments that at high salt concentrations, there was no effect on the settling behavior.Keywords: Coalescence; electrolytes; liquid-liquid separation; high viscosity; mixer- settler.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2211493 A Study on Remote On-Line Diagnostic System for Vehicles by Integrating the Technology of OBD, GPS, and 3G
Authors: Jyong Lin, Shih-Chang Chen, Yu-Tsen Shih, Shi-Huang Chen
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This paper presents a remote on-line diagnostic system for vehicles via the use of On-Board Diagnostic (OBD), GPS, and 3G techniques. The main parts of the proposed system are on-board computer, vehicle monitor server, and vehicle status browser. First, the on-board computer can obtain the location of deriver and vehicle status from GPS receiver and OBD interface, respectively. Then on-board computer will connect with the vehicle monitor server through 3G network to transmit the real time vehicle system status. Finally, vehicle status browser could show the remote vehicle status including vehicle speed, engine rpm, battery voltage, engine coolant temperature, and diagnostic trouble codes. According to the experimental results, the proposed system can help fleet managers and car knockers to understand the remote vehicle status. Therefore this system can decrease the time of fleet management and vehicle repair due to the fleet managers and car knockers who find the diagnostic trouble messages in time.Keywords: Diagnostic Trouble Code (DTC), Electronic Control Unit (ECU), Global Position System (GPS), On-Board Diagnostic (OBD).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3002492 Physicochemical Activities of Blood Biomarkers Due to Ingestible Radon-222 in Drinking Water and Its Associated Health Consequences
Authors: I. M. Yusuff, A. M. Arogunjo, S. B. Ibikunle, O. M. Oni, P. O. Osho
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Generally, water contamination is a serious health concern, affecting millions of people worldwide every year. Among the water contaminants, radon is a radioactive contaminant understudied and under-regulated. It produces many adverse health effects, including cancer. It is a natural gas that cannot be seen, tasted, or smelled. It develops from the radioactive decay of radium found in the rock of soil and has been considered a health hazard due to its radioactivity in nature. To examine its effects and physicochemical characteristics on the blood biomarkers due to its ingestion in drinking water, its concentrations were monitored and measured in treated and untreated water using Electronic Radon Active Detector (RAD7), while human blood samples were collected using the required laboratory tools. The blood samples were collected and examined physicochemically using semi-automated chemistry analyzer to evaluate the chemistry parameters of the blood. Statistically, results obtained were analyzed using T-test of variables at 95% confidence interval. The outcome of results revealed 112.03 Bq/m3, 561.67 Bq/m3 and 2,753.00 Bq/m3 of radon-222 concentrations in the three water samples used respectively. Demographically, chemistry parameters biomarkers of the blood determined displayed some levels of variations due to radon-222 contaminants ingested from untreated water. Also, analyzed results of blood revealed the associations between the physicochemical parameters of the blood biomarkers and volunteers’ health consequences. The consequences observed were more severed with group B volunteers than group A, due to high level of radon contaminants in borehole water consumed by group B than in well water consumed by group A. The percentages of elevated and depressed biomarkers observed differ from initial reference values and, were the dysfunction indicators. They are directly or indirectly associated to human’s state of health. Most significant biomarkers affected were; HCO3, Cl, K, Cr and Na, they are relevant biomarkers in medicine to determine human’s state of health at any point in time.
Keywords: Radioactive, radon, biomarker, ingestion, dysfunction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 193491 MHD Non-Newtonian Nanofluid Flow over a Permeable Stretching Sheet with Heat Generation and Velocity Slip
Authors: Rama Bhargava, Mania Goyal
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The problem of magnetohydrodynamics boundary layer flow and heat transfer on a permeable stretching surface in a second grade nanofluid under the effect of heat generation and partial slip is studied theoretically. The Brownian motion and thermophoresis effects are also considered. The boundary layer equations governed by the PDE’s are transformed into a set of ODE’s with the help of local similarity transformations. The differential equations are solved by variational finite element method. The effects of different controlling parameters on the flow field and heat transfer characteristics are examined. The numerical results for the dimensionless velocity, temperature and nanoparticle volume fraction as well as the reduced Nusselt and Sherwood number have been presented graphically. The comparison confirmed excellent agreement. The present study is of great interest in coating and suspensions, cooling of metallic plate, oils and grease, paper production, coal water or coal-oil slurries, heat exchangers technology, materials processing exploiting.
Keywords: Viscoelastic nanofluid, partial slip, stretching sheet, heat generation/absorption, MHD flow, FEM.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3267490 Presentation of a Mix Algorithm for Estimating the Battery State of Charge Using Kalman Filter and Neural Networks
Authors: Amin Sedighfar, M. R. Moniri
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Determination of state of charge (SOC) in today’s world becomes an increasingly important issue in all the applications that include a battery. In fact, estimation of the SOC is a fundamental need for the battery, which is the most important energy storage in Hybrid Electric Vehicles (HEVs), smart grid systems, drones, UPS and so on. Regarding those applications, the SOC estimation algorithm is expected to be precise and easy to implement. This paper presents an online method for the estimation of the SOC of Valve-Regulated Lead Acid (VRLA) batteries. The proposed method uses the well-known Kalman Filter (KF), and Neural Networks (NNs) and all of the simulations have been done with MATLAB software. The NN is trained offline using the data collected from the battery discharging process. A generic cell model is used, and the underlying dynamic behavior of the model has used two capacitors (bulk and surface) and three resistors (terminal, surface, and end), where the SOC determined from the voltage represents the bulk capacitor. The aim of this work is to compare the performance of conventional integration-based SOC estimation methods with a mixed algorithm. Moreover, by containing the effect of temperature, the final result becomes more accurate.
Keywords: Kalman filter, neural networks, state-of-charge, VRLA battery.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1394489 Adomian’s Decomposition Method to Generalized Magneto-Thermoelasticity
Authors: Hamdy M. Youssef, Eman A. Al-Lehaibi
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Due to many applications and problems in the fields of plasma physics, geophysics, and other many topics, the interaction between the strain field and the magnetic field has to be considered. Adomian introduced the decomposition method for solving linear and nonlinear functional equations. This method leads to accurate, computable, approximately convergent solutions of linear and nonlinear partial and ordinary differential equations even the equations with variable coefficients. This paper is dealing with a mathematical model of generalized thermoelasticity of a half-space conducting medium. A magnetic field with constant intensity acts normal to the bounding plane has been assumed. Adomian’s decomposition method has been used to solve the model when the bounding plane is taken to be traction free and thermally loaded by harmonic heating. The numerical results for the temperature increment, the stress, the strain, the displacement, the induced magnetic, and the electric fields have been represented in figures. The magnetic field, the relaxation time, and the angular thermal load have significant effects on all the studied fields.
Keywords: Adomian’s Decomposition Method, magneto-thermoelasticity, finite conductivity, iteration method, thermal load.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 785488 Global Kinetics of Direct Dimethyl Ether Synthesis Process from Syngas in Slurry Reactor over a Novel Cu-Zn-Al-Zr Slurry Catalyst
Authors: Zhen Chen, Haitao Zhang, Weiyong Ying, Dingye Fang
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The direct synthesis process of dimethyl ether (DME) from syngas in slurry reactors is considered to be promising because of its advantages in caloric transfer. In this paper, the influences of operating conditions (temperature, pressure and weight hourly space velocity) on the conversion of CO, selectivity of DME and methanol were studied in a stirred autoclave over Cu-Zn-Al-Zr slurry catalyst, which is far more suitable to liquid phase dimethyl ether synthesis process than bifunctional catalyst commercially. A Langmuir- Hinshelwood mechanism type global kinetics model for liquid phase DME direct synthesis based on methanol synthesis models and a methanol dehydration model has been investigated by fitting our experimental data. The model parameters were estimated with MATLAB program based on general Genetic Algorithms and Levenberg-Marquardt method, which is suitably fitting experimental data and its reliability was verified by statistical test and residual error analysis.Keywords: alcohol/ether fuel, Cu-Zn-Al-Zr slurry catalyst, global kinetics, slurry reactor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5503487 Analysis of Thermal Deformation of a Rough Slider and Its Asperities and Its Impact on Load Generation in Parallel Sliders
Authors: Prawal Sinha, Getachew Adamu
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Heating is inevitable in any bearing operation. This leads to not only the thinning of the lubricant but also could lead to a thermal deformation of the bearing. The present work is an attempt to analyze the influence of thermal deformation on the thermohydrodynamic lubrication of infinitely long tilted pad slider rough bearings. As a consequence of heating the slider is deformed and is assumed to take a parabolic shape. Also the asperities expand leading to smaller effective film thickness. Two different types of surface roughness are considered: longitudinal roughness and transverse roughness. Christensen-s stochastic approach is used to derive the Reynolds-type equations. Density and viscosity are considered to be temperature dependent. The modified Reynolds equation, momentum equation, continuity equation and energy equation are decoupled and solved using finite difference method to yield various bearing characteristics. From the numerical simulations it is observed that the performance of the bearing is significantly affected by the thermal distortion of the slider and asperities and even the parallel sliders seem to carry some load.Keywords: Thermal Deformation, Tilted pad slider bearing, longitudinal roughness, transverse roughness, load capacity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1860486 A Numerical Framework to Investigate Intake Aerodynamics Behavior in Icing Conditions
Authors: Ali Mirmohammadi, Arash Taheri, Meysam Mohammadi-Amin
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One of the major parts of a jet engine is air intake, which provides proper and required amount of air for the engine to operate. There are several aerodynamic parameters which should be considered in design, such as distortion, pressure recovery, etc. In this research, the effects of lip ice accretion on pitot intake performance are investigated. For ice accretion phenomenon, two supervised multilayer neural networks (ANN) are designed, one for ice shape prediction and another one for ice roughness estimation based on experimental data. The Fourier coefficients of transformed ice shape and parameters include velocity, liquid water content (LWC), median volumetric diameter (MVD), spray time and temperature are used in neural network training. Then, the subsonic intake flow field is simulated numerically using 2D Navier-Stokes equations and Finite Volume approach with Hybrid mesh includes structured and unstructured meshes. The results are obtained in different angles of attack and the variations of intake aerodynamic parameters due to icing phenomenon are discussed. The results show noticeable effects of ice accretion phenomenon on intake behavior.Keywords: Artificial Neural Network, Ice Accretion, IntakeAerodynamics, Design Parameters, Finite Volume Method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2193485 Granularity Analysis for Spatio-Temporal Web Sensors
Authors: Shun Hattori
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In recent years, many researches to mine the exploding Web world, especially User Generated Content (UGC) such as weblogs, for knowledge about various phenomena and events in the physical world have been done actively, and also Web services with the Web-mined knowledge have begun to be developed for the public. However, there are few detailed investigations on how accurately Web-mined data reflect physical-world data. It must be problematic to idolatrously utilize the Web-mined data in public Web services without ensuring their accuracy sufficiently. Therefore, this paper introduces the simplest Web Sensor and spatiotemporallynormalized Web Sensor to extract spatiotemporal data about a target phenomenon from weblogs searched by keyword(s) representing the target phenomenon, and tries to validate the potential and reliability of the Web-sensed spatiotemporal data by four kinds of granularity analyses of coefficient correlation with temperature, rainfall, snowfall, and earthquake statistics per day by region of Japan Meteorological Agency as physical-world data: spatial granularity (region-s population density), temporal granularity (time period, e.g., per day vs. per week), representation granularity (e.g., “rain" vs. “heavy rain"), and media granularity (weblogs vs. microblogs such as Tweets).Keywords: Granularity analysis, knowledge extraction, spatiotemporal data mining, Web credibility, Web mining, Web sensor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1874484 Numerical Study of Laminar Mixed Convection Heat Transfer of a Nanofluid in a Concentric Annular Tube Using Two-Phase Mixture Model
Authors: Roghayyeh Motallebzadeh, Shahin Hajizadeh, Mohammad Reza Ghasemi
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Laminar mixed Convection heat transfer of a nanofluid with prescribed constant heat flux on the inner wall of horizontal annular tube has been studied numerically based on two-phase mixture model in different Rayleigh Numbers and Azimuth angles. Effects of applying of different volume fractions of Al2O3 nanoparticles in water as a base fluid on hydrodynamic and thermal behaviors of the fluid flow such as axial velocity, secondary flow, temperature, heat transfer coefficient and friction coefficient at the inner and outer wall region, has been investigated. Conservation equations in elliptical form has been utilized and solved in three dimensions for a steady flow. It is observed that, there is a good agreement between results in this work and previously published experimental and numerical works on mixed convection in horizontal annulus. These particles cause to increase convection heat transfer coefficient of the fluid, meanwhile there is no considerable effect on friction coefficient.
Keywords: Buoyancy force, Laminar mixed convection, Mixture model, Nanofluid, Two-phase.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2814