Search results for: chemical analysis
7471 Comparative Analysis of the Stochastic and Parsimonious Interest Rates Models on Croatian Government Market
Authors: Zdravka Aljinović, Branka Marasović, Blanka Škrabić
Abstract:
The paper provides a discussion of the most relevant aspects of yield curve modeling. Two classes of models are considered: stochastic and parsimonious function based, through the approaches developed by Vasicek (1977) and Nelson and Siegel (1987). Yield curve estimates for Croatia are presented and their dynamics analyzed and finally, a comparative analysis of models is conducted.Keywords: the term structure of interest rates, Vasicek model, Nelson-Siegel model, Croatian Government market.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15017470 Leisure and Perceived Wellness of Nursing Students: A Canonical Correlation Analysis
Authors: Ming-Tsang Wu
Abstract:
The purpose of this study was to explore the correlation between leisure participation and perceived wellness, with the students of a nursing college in southern Taiwan as the subjects. One thousand six hundred and ninety-six (1,696) surveys were sent, and 1,408 surveys were received for an 83.02% valid response rate. Using canonical correlation analysis to analyze the data, the results showed that the linear combination of the two sets of variable produces five significant canonical variates. Out of the five canonical variates, only the first has sufficient explanatory power. The canonical correlation coefficient of first canonical variate is 0.660. This indicated that leisure participation and perceived wellness are significantly correlated.Keywords: Leisure, perceived wellness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18787469 Investigation of Green Dye-Sensitized Solar Cells Based on Natural Dyes
Authors: M. Hosseinnezhad, K. Gharanjig
Abstract:
Natural dyes, extracted from black carrot and bramble, were utilized as photosensitizers to prepare dye-sensitized solar cells (DSSCs). Spectrophotometric studies of the natural dyes in solution and on a titanium dioxide substrate were carried out in order to assess changes in the status of the dyes. The results show that the bathochromic shift is seen on the photo-electrode substrate. The chemical binding of the natural dyes at the surface photo-electrode were increased by the chelating effect of the Ti(IV) ions. The cyclic voltammetry results showed that all extracts are suitable to be performed in DSSCs. Finally, photochemical performance and stability of DSSCs based on natural dyes were studied. The DSSCs sensitized by black carrot extract have been reported to achieve up to Jsc=1.17 mAcm-2, Voc= 0.55 V, FF= 0.52, η=0.34%, whereas Bramble extract can obtain up to Jsc=2.24 mAcm-2, Voc= 0.54 V, FF= 0.57, η=0.71%. The power conversion efficiency was obtained from the mixed dyes in DSSCs. The power conversion efficiency of dye-sensitized solar cells using mixed Black carrot and Bramble dye is the average of the their efficiency in single DSSCs.
Keywords: Anthocyanin, dye-sensitized solar cells, green energy, optical materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10857468 Experimental Study on Using the Aluminum Sacrificial Anode as a Cathodic Protection for Marine Structures
Authors: A. Radwan, A. Elbatran, A. Mehanna, M. Shehadeh
Abstract:
The corrosion is natural chemical phenomenon that is applied in many engineering structures. Hence, it is one of the important topics to study in the engineering research. Ship and offshore structures are most exposed to corrosion due to the presence of corrosive medium of air and the seawater. Consequently, investigation of the corrosion behavior and properties over ship and offshore hulls is one of the important topics to study in the marine engineering research. Using sacrificial anode is the most popular solution for protecting marine structures from corrosion. Hence, this research investigates the extent of corrosion between the composite ship model and relative velocity of water, along with the sacrificial aluminum anode consumption and its degree of protection in seawater. In this study, the consumption rate of sacrificial aluminum anode with respect to relative velocity at different Reynold’s numbers was studied experimentally, and it was found that, the degree of cathodic protection represented by the cathode potential at a given distance from the aluminum anode was decreased slightly with increment of the relative velocity.Keywords: Corrosion, Reynold’s numbers, sacrificial anode, velocity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19987467 Measurement of Operational and Environmental Performance of the Coal-Fired Power Plants in India by Using Data Envelopment Analysis
Authors: Vijay Kumar Bajpai, Sudhir Kumar Singh
Abstract:
In this study, the performance analyses of the twenty five Coal-Fired Power Plants (CFPPs) used for electricity generation are carried out through various Data Envelopment Analysis (DEA) models. Three efficiency indices are defined and pursued. During the calculation of the operational performance, energy and non-energy variables are used as input, and net electricity produced is used as desired output (Model-1). CO2 emitted to the environment is used as the undesired output (Model-2) in the computation of the pure environmental performance while in Model-3 CO2 emissions is considered as detrimental input in the calculation of operational and environmental performance. Empirical results show that most of the plants are operating in increasing returns to scale region and Mettur plant is efficient one with regards to energy use and environment. The result also indicates that the undesirable output effect is insignificant in the research sample. The present study will provide clues to plant operators towards raising the operational and environmental performance of CFPPs.
Keywords: Coal fired power plants, environmental performance, data envelopment analysis, operational performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23617466 Finite Element Prediction and Experimental Verification of the Failure Pattern of Proximal Femur using Quantitative Computed Tomography Images
Authors: Majid Mirzaei, Saeid Samiezadeh , Abbas Khodadadi, Mohammad R. Ghazavi
Abstract:
This paper presents a novel method for prediction of the mechanical behavior of proximal femur using the general framework of the quantitative computed tomography (QCT)-based finite element Analysis (FEA). A systematic imaging and modeling procedure was developed for reliable correspondence between the QCT-based FEA and the in-vitro mechanical testing. A speciallydesigned holding frame was used to define and maintain a unique geometrical reference system during the analysis and testing. The QCT images were directly converted into voxel-based 3D finite element models for linear and nonlinear analyses. The equivalent plastic strain and the strain energy density measures were used to identify the critical elements and predict the failure patterns. The samples were destructively tested using a specially-designed gripping fixture (with five degrees of freedom) mounted within a universal mechanical testing machine. Very good agreements were found between the experimental and the predicted failure patterns and the associated load levels.Keywords: Bone, Osteoporosis, Noninvasive methods, Failure Analysis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20987465 Effect of Operating Conditions on Forward Osmosis for Nutrient Rejection Using Magnesium Chloride as a Draw Solution
Authors: Yatnanta Padma Devia, Tsuyoshi Imai, Takaya Higuchi, Ariyo Kanno, Koichi Yamamoto, Masahiko Sekine
Abstract:
Advanced treatments such as forward osmosis (FO) can be used to separate or reject nutrients from secondary treated effluents. Forward osmosis uses the chemical potential across the membrane, which is the osmotic pressure gradient, to induce water to flow through the membrane from a feed solution (FS) into a draw solution (DS). The performance of FO is affected by the membrane characteristics, composition of the FS and DS, and operating conditions. The aim of this study was to investigate the optimum velocity and temperature for nutrient rejection and water flux performance in FO treatments. MgCl2 was used as the DS in the FO process. The results showed that higher cross flow velocities yielded higher water fluxes. High rejection of nutrients was achieved by using a moderate cross flow velocity at 0.25 m/s. Nutrient rejection was insensitive to temperature variation, whereas water flux was significantly impacted by it. A temperature of 25°C was found to be good for nutrient rejection.Keywords: Cross flow velocity, forward osmosis, magnesium chloride, temperature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26777464 Experimental and Simulation Stress Strain Comparison of Hot Single Point Incremental Forming
Authors: Amar Al-Obaidi, Verena Kräusel, Dirk Landgrebe
Abstract:
Induction assisted single point incremental forming (IASPIF) is a flexible method and can be simply utilized to form a high strength alloys. Due to the interaction between the mechanical and thermal properties during IASPIF an evaluation for the process is necessary to be performed analytically. Therefore, a numerical simulation was carried out in this paper. The numerical analysis was operated at both room and elevated temperatures then compared with experimental results. Fully coupled dynamic temperature displacement explicit analysis was used to simulated the hot single point incremental forming. The numerical analysis was indicating that during hot single point incremental forming were a combination between complicated compression, tension and shear stresses. As a result, the equivalent plastic strain was increased excessively by rising both the formed part depth and the heating temperature during forming. Whereas, the forming forces were decreased from 5 kN at room temperature to 0.95 kN at elevated temperature. The simulation shows that the maximum true strain was occurred in the stretching zone which was the same as in experiment.Keywords: Induction heating, single point incremental forming, FE modeling, advanced high strength steel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9377463 A Comparative Analysis Approach Based on Fuzzy AHP, TOPSIS and PROMETHEE for the Selection Problem of GSCM Solutions
Authors: Omar Boutkhoum, Mohamed Hanine, Abdessadek Bendarag
Abstract:
Sustainable economic growth is nowadays driving firms to extend toward the adoption of many green supply chain management (GSCM) solutions. However, the evaluation and selection of these solutions is a matter of concern that needs very serious decisions, involving complexity owing to the presence of various associated factors. To resolve this problem, a comparative analysis approach based on multi-criteria decision-making methods is proposed for adequate evaluation of sustainable supply chain management solutions. In the present paper, we propose an integrated decision-making model based on FAHP (Fuzzy Analytic Hierarchy Process), TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) and PROMETHEE (Preference Ranking Organisation METHod for Enrichment Evaluations) to contribute to a better understanding and development of new sustainable strategies for industrial organizations. Due to the varied importance of the selected criteria, FAHP is used to identify the evaluation criteria and assign the importance weights for each criterion, while TOPSIS and PROMETHEE methods employ these weighted criteria as inputs to evaluate and rank the alternatives. The main objective is to provide a comparative analysis based on TOPSIS and PROMETHEE processes to help make sound and reasoned decisions related to the selection problem of GSCM solution.Keywords: GSCM solutions, multi-criteria analysis, FAHP, TOPSIS, PROMETHEE, decision support system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9387462 Road Safety in Great Britain: An Exploratory Data Analysis
Authors: Jatin Kumar Choudhary, Naren Rayala, Abbas Eslami Kiasari, Fahimeh Jafari
Abstract:
Great Britain has one of the safest road networks in the world. However, the consequences of any death or serious injury are devastating for loved ones, as well as for those who help the severely injured. This paper aims to analyse Great Britain's road safety situation and show the response measures for areas where the total damage caused by accidents can be significantly and quickly reduced. For the past 30 years, the UK has had a good record in reducing fatalities over the past 30 years, there is still a considerable number of road deaths. The government continues to scale back road deaths empowering responsible road users by identifying and prosecuting the parameters that make the roads less safe. This study represents an exploratory analysis with deep insights which could provide policy makers with invaluable insights into how accidents happen and how they can be mitigated. We use STATS19 data published by the UK government. Since we need more information about locations which is not provided in STATA19, we first expand the features of the dataset using OpenStreetMap and Visual Crossing. This paper also provides a discussion regarding new road safety methods.
Keywords: Road safety, data analysis, OpenStreetMap, feature expanding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3447461 Optimization of Diluted Organic Acid Pretreatment on Rice Straw Using Response Surface Methodology
Authors: Rotchanaphan Hengaroonprasan, Malinee Sriariyanun, Prapakorn Tantayotai, Supacharee Roddecha, Kraipat Cheenkachorn
Abstract:
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 24007460 Research on Pressed Pile Test and Finite Element Analysis of Large-diameter Steel Pipe Pile of Zhanjiang Port
Authors: Ran Zhao, Zhi-liang Dong, You-yuan Wang, Lin-wang Su
Abstract:
In order to study pressed pile test and ultimate bearing capacity character of large-diameter steel pipe pile, based on two high-piled wharfs of Zhanjiang Port, pressed pile test and numerical simulation of three large-diameter steel pipe piles are analyzed in this paper. Anchored pile method is used to pressed pile test, and the curves of Q-s and ultimate bearing capacity are attained. Then the three piles are numerically simulated by ABAQUS, and results of numerical simulation and those of field test are comparatively analyzed. The results show that settlement value of numerical simulation is larger than that of field test in the process of loading, the difference value is widening with the increasing of load, and the ultimate difference value of settlement is 20% to 30%.Keywords: Large-diameter steel pipe pile, field test, finite element analysis, comparative analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19957459 Characterization of Electrospun Carbon Nanofiber Doped Polymer Composites
Authors: Atilla Evcin, Bahri Ersoy, Süleyman Akpınar, I. Sinan Atlı
Abstract:
Ceramic, polymer and composite nanofibers are nowadays begun to be utilized in many fields of nanotechnology. By the means of dimensions, these fibers are as small as nano scale but because of having large surface area and microstructural characteristics, they provide unique mechanic, optical, magnetic, electronic and chemical properties. In terms of nanofiber production, electrospinning has been the most widely used technique in recent years. In this study, carbon nanofibers have been synthesized from solutions of Polyacrylonitrile (PAN)/ N,N-dimethylformamide (DMF) by electrospinning method. The carbon nanofibers have been stabilized by oxidation at 250 °C for 2 h in air and carbonized at 750 °C for 1 h in H2/N2. Images of carbon nanofibers have been taken with scanning electron microscopy (SEM). The images have been analyzed to study the fiber morphology and to determine the distribution of the fiber diameter using FibraQuant 1.3 software. Then polymer composites have been produced from mixture of carbon nanofibers and silicone polymer. The final polymer composites have been characterized by X-ray diffraction method and scanning electron microscopy (SEM) energy dispersive X-ray (EDX) measurements. These results have been reported and discussed. At result, homogeneous carbon nanofibers with 100-167 nm of diameter were obtained with optimized electrospinning conditions.
Keywords: Electrospinning, characterization, composites, nanofiber.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9457458 Urban Big Data: An Experimental Approach to Building-Value Estimation Using Web-Based Data
Authors: Sun-Young Jang, Sung-Ah Kim, Dongyoun Shin
Abstract:
Current real-estate value estimation, difficult for laymen, usually is performed by specialists. This paper presents an automated estimation process based on big data and machine-learning technology that calculates influences of building conditions on real-estate price measurement. The present study analyzed actual building sales sample data for Nonhyeon-dong, Gangnam-gu, Seoul, Korea, measuring the major influencing factors among the various building conditions. Further to that analysis, a prediction model was established and applied using RapidMiner Studio, a graphical user interface (GUI)-based tool for derivation of machine-learning prototypes. The prediction model is formulated by reference to previous examples. When new examples are applied, it analyses and predicts accordingly. The analysis process discerns the crucial factors effecting price increases by calculation of weighted values. The model was verified, and its accuracy determined, by comparing its predicted values with actual price increases.Keywords: Big data, building-value analysis, machine learning, price prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11647457 The Application of Non-quantitative Modelling in the Analysis of a Network Warfare Environment
Authors: N. Veerasamy, JPH Eloff
Abstract:
Network warfare is an emerging concept that focuses on the network and computer based forms through which information is attacked and defended. Various computer and network security concepts thus play a role in network warfare. Due the intricacy of the various interacting components, a model to better understand the complexity in a network warfare environment would be beneficial. Non-quantitative modeling is a useful method to better characterize the field due to the rich ideas that can be generated based on the use of secular associations, chronological origins, linked concepts, categorizations and context specifications. This paper proposes the use of non-quantitative methods through a morphological analysis to better explore and define the influential conditions in a network warfare environment.
Keywords: Morphological, non-quantitative, network warfare.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13877456 Optimization of Surface Finish in Milling Operation Using Live Tooling via Taguchi Method
Authors: Harish Kumar Ponnappan, Joseph C. Chen
Abstract:
The main objective of this research is to optimize the surface roughness of a milling operation on AISI 1018 steel using live tooling on a HAAS ST-20 lathe. In this study, Taguchi analysis is used to optimize the milling process by investigating the effect of different machining parameters on surface roughness. The L9 orthogonal array is designed with four controllable factors with three different levels each and an uncontrollable factor, resulting in 18 experimental runs. The optimal parameters determined from Taguchi analysis were feed rate – 76.2 mm/min, spindle speed 1150 rpm, depth of cut – 0.762 mm and 2-flute TiN coated high-speed steel as tool material. The process capability Cp and process capability index Cpk values were improved from 0.62 and -0.44 to 1.39 and 1.24 respectively. The average surface roughness values from the confirmation runs were 1.30 µ, decreasing the defect rate from 87.72% to 0.01%. The purpose of this study is to efficiently utilize the Taguchi design to optimize the surface roughness in a milling operation using live tooling.
Keywords: Live tooling, surface roughness, Taguchi analysis, Computer Numerical Control (CNC) milling operation, CNC turning operation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7717455 Asymptotic Analysis of Instant Messaging Service with Relay Nodes
Authors: Muhammad T. Alam, Zheng Da Wu
Abstract:
In this paper, we provide complete end-to-end delay analyses including the relay nodes for instant messages. Message Session Relay Protocol (MSRP) is used to provide congestion control for large messages in the Instant Messaging (IM) service. Large messages are broken into several chunks. These chunks may traverse through a maximum number of two relay nodes before reaching destination according to the IETF specification of the MSRP relay extensions. We discuss the current solutions of sending large instant messages and introduce a proposal to reduce message flows in the IM service. We consider virtual traffic parameter i.e., the relay nodes are stateless non-blocking for scalability purpose. This type of relay node is also assumed to have input rate at constant bit rate. We provide a new scheduling policy that schedules chunks according to their previous node?s delivery time stamp tags. Validation and analysis is shown for such scheduling policy. The performance analysis with the model introduced in this paper is simple and straight forward, which lead to reduced message flows in the IM service.
Keywords: Instant messaging, stateless, chunking, MSRP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16207454 Buckling Analysis of Rectangular Plates under the Combined Action of Shear and Uniaxial Stresses
Authors: V. Piscopo
Abstract:
In the classical buckling analysis of rectangular plates subjected to the concurrent action of shear and uniaxial forces, the Euler shear buckling stress is generally evaluated separately, so that no influence on the shear buckling coefficient, due to the in-plane tensile or compressive forces, is taken into account. In this paper the buckling problem of simply supported rectangular plates, under the combined action of shear and uniaxial forces, is discussed from the beginning, in order to obtain new project formulas for the shear buckling coefficient that take into account the presence of uniaxial forces. Furthermore, as the classical expression of the shear buckling coefficient for simply supported rectangular plates is considered only a “rough" approximation, as the exact one is defined by a system of intersecting curves, the convergence and the goodness of the classical solution are analyzed, too. Finally, as the problem of the Euler shear buckling stress evaluation is a very important topic for a variety of structures, (e.g. ship ones), two numerical applications are carried out, in order to highlight the role of the uniaxial stresses on the plating scantling procedures and the goodness of the proposed formulas.Keywords: Buckling analysis, Shear, Uniaxial Stresses.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29367453 Spectral Analysis of Speech: A New Technique
Authors: Neeta Awasthy, J.P.Saini, D.S.Chauhan
Abstract:
ICA which is generally used for blind source separation problem has been tested for feature extraction in Speech recognition system to replace the phoneme based approach of MFCC. Applying the Cepstral coefficients generated to ICA as preprocessing has developed a new signal processing approach. This gives much better results against MFCC and ICA separately, both for word and speaker recognition. The mixing matrix A is different before and after MFCC as expected. As Mel is a nonlinear scale. However, cepstrals generated from Linear Predictive Coefficient being independent prove to be the right candidate for ICA. Matlab is the tool used for all comparisons. The database used is samples of ISOLET.Keywords: Cepstral Coefficient, Distance measures, Independent Component Analysis, Linear Predictive Coefficients.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19577452 Economical Analysis of Thermal Energy Storage by Partially Operation
Authors: Z. Noranai, M.Z. Md Yusof
Abstract:
Building Sector is the major electricity consumer and it is costly to building owners. Therefore the application of thermal energy storage (TES) has gained attractive to reduce energy cost. Many attractive tariff packages are being offered by the electricity provider to promote TES. The tariff packages offered higher cost of electricity during peak period and lower cost of electricity during off peak period. This paper presented the return of initial investment by implementing a centralized air-conditioning plant integrated with thermal energy storage with partially operation strategies. Building load profile will be calculated hourly according to building specification and building usage trend. TES operation conditions will be designed according to building load demand profile, storage capacity, tariff packages and peak/off peak period. The Payback Period analysis method was used to evaluate economic analysis. The investment is considered a good investment where by the initial cost is recovered less than ten than seven years.Keywords: building load profile, energy consumption, payback period, thermal energy storage
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20117451 Multi Response Optimization in Drilling Al6063/SiC/15% Metal Matrix Composite
Authors: Hari Singh, Abhishek Kamboj, Sudhir Kumar
Abstract:
This investigation proposes a grey-based Taguchi method to solve the multi-response problems. The grey-based Taguchi method is based on the Taguchi’s design of experimental method, and adopts grey relational analysis (GRA) to transfer multi-response problems into single-response problems. In this investigation, an attempt has been made to optimize the drilling process parameters considering weighted output response characteristics using grey relational analysis. The output response characteristics considered are surface roughness, burr height and hole diameter error under the experimental conditions of cutting speed, feed rate, step angle, and cutting environment. The drilling experiments were conducted using L27 orthogonal array. A combination of orthogonal array, design of experiments and grey relational analysis was used to ascertain best possible drilling process parameters that give minimum surface roughness, burr height and hole diameter error. The results reveal that combination of Taguchi design of experiment and grey relational analysis improves surface quality of drilled hole.
Keywords: Metal matrix composite, Drilling, Optimization, step drill, Surface roughness, burr height, hole diameter error.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32557450 Mercury Removing Capacity of Multiwall Carbon Nanotubes as Detected by Cold Vapor Atomic Absorption Spectroscopy: Kinetic & Equilibrium Studies
Authors: Yasser M. Moustafa, Rania E. Morsi, Mohammed Fathy
Abstract:
Multiwall carbon nanotubes, prepared by chemical vapor deposition, have an average diameter of 60-100 nm as shown by High Resolution Transmittance Electron Microscope, HR-TEM. The Multiwall carbon nanotubes (MWCNTs) were further characterized using X-ray Diffraction and Raman Spectroscopy. Mercury uptake capacity of MWCNTs was studied using batch adsorption method at different concentration ranges up to 150 ppm. Mercury concentration (before and after the treatment) was measured using cold vapor atomic absorption spectroscopy. The effect of time, concentration, pH and adsorbent dose were studied. MWCNT were found to perform complete absorption in the sub-ppm concentrations (parts per billion levels) while for high concentrations, the adsorption efficiency was 92% at the optimum conditions; 0.1 g of the adsorbent at 150 ppm mercury (II) solution. The adsorption of mercury on MWCNTs was found to follow the Freundlich adsorption isotherm and the pseudo-second order kinetic model.
Keywords: Cold Vapor Atomic Absorption Spectroscopy, Hydride System, Mercury Removing, Multi Wall Carbon Nanotubes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24197449 Geometric and Material Nonlinear Analysis of Reinforced Concrete Structure Considering Soil-Structure Interaction
Authors: Mohamed M. El-Gendy, Ibrahim A. El-Arabi, Rafik W. Abdel-Missih, Omar A. Kandil
Abstract:
In the present research, a finite element model is presented to study the geometrical and material nonlinear behavior of reinforced concrete plane frames considering soil-structure interaction. The nonlinear behaviors of concrete and reinforcing steel are considered both in compression and tension up to failure. The model takes account also for the number, diameter, and distribution of rebar along every cross section. Soil behavior is taken into consideration using four different models; namely: linear-, nonlinear Winkler's model, and linear-, nonlinear continuum model. A computer program (NARC) is specially developed in order to perform the analysis. The results achieved by the present model show good agreement with both theoretical and experimental published literature. The nonlinear behavior of a rectangular frame resting on soft soil up to failure using the proposed model is introduced for demonstration.Keywords: Nonlinear analysis, Geometric nonlinearity, Material nonlinearity, Reinforced concrete, Finite element method, Soilstructure interaction, Winkler's soil model, Continuum soil model
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26657448 Liquid Temperature Effect on Sound Propagation in Polymeric Solution with Gas Bubbles
Authors: S. Levitsky
Abstract:
Acoustic properties of polymeric liquids are high sensitive to free gas traces in the form of fine bubbles. Their presence is typical for such liquids because of chemical reactions, small wettability of solid boundaries, trapping of air in technological operations, etc. Liquid temperature influences essentially its rheological properties, which may have an impact on the bubble pulsations and sound propagation in the system. The target of the paper is modeling of the liquid temperature effect on single bubble dynamics and sound dispersion and attenuation in polymeric solution with spherical gas bubbles. The basic sources of attenuation (heat exchange between gas in microbubbles and surrounding liquid, rheological and acoustic losses) are taken into account. It is supposed that in the studied temperature range the interface mass transfer has a minor effect on bubble dynamics. The results of the study indicate that temperature raise yields enhancement of bubble pulsations and increase in sound attenuation in the near-resonance range and may have a strong impact on sound dispersion in the liquid-bubble mixture at frequencies close to the resonance frequency of bubbles.Keywords: Sound propagation, gas bubbles, temperature effect, polymeric liquid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22757447 Parental Expectations and Student Performance in Secondary School Mathematics Education
Authors: Daya Weerasinghe
Abstract:
Parental expectations often differ to that of their children and the influence and involvement of parents, at home, may affect the student performance in the classroom. This paper presents results from a survey of Asian and European background secondary school mathematics students (N=128) in Melbourne, Australia. Student responses to survey questions were analysed using confirmatory factor analysis, followed by t-tests and ANOVA. The aim of the analysis was to identify similarities and differences in parental expectations in relation to ethnicity, gender, and the year level of the students. The notable findings from the analysis showed no significant difference (at 0.05 level) in parental expectations and student performance, in relation to ethnicity or gender. Conversely, there was a significant difference in both parental expectations and student performance between year 7 and year 12 students. Further, whilst there was a significant difference in parental expectations between year 7 and year 11 students, the students’ performances were not significantly different. The results suggest further research may be needed to understand the parental expectations and student performance between the lower and upper secondary school mathematics students.
Keywords: Ethnic background, gender, parental expectations, student performance, year level.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29947446 Automated Separation of Organic Liquids through Their Boiling Points
Authors: Muhammad Tahir Qadri, Syed Shafi-Uddin Qadri, Faizan Farid, Nabeel Abid
Abstract:
This paper discuss the separation of the miscible liquids by means of fractional distillation. For complete separation of liquids, the process of heating, condensation, separation and storage is done automatically to achieve the objective. PIC micro-controller has been used to control each and every process of the work. The controller also controls the storage process by activating and deactivating the conveyors. The liquids are heated which on reaching their respective boiling points evaporate and enter the condensation chamber where they convert into liquid. The liquids are then directed to their respective tanks by means of stepper motor which moves in three directions, each movement into different tank. The tank on filling sends the signal to controller which then opens the solenoid valves. The tank is emptied into the beakers below the nozzle. As the beaker filled, the nozzle closes and the conveyors come into operation. The filled beaker is replaced by an empty beaker from behind. The work can be used in oil industries, chemical industries and paint industries.Keywords: Miscible Liquid Separation Unit, Distillation, Waste Water Treatment, Organic Liquids Collection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17437445 Optimization of Petroleum Refinery Configuration Design with Logic Propositions
Authors: Cheng Seong Khor, Xiao Qi Yeoh
Abstract:
This work concerns the topological optimization problem for determining the optimal petroleum refinery configuration. We are interested in further investigating and hopefully advancing the existing optimization approaches and strategies employing logic propositions to conceptual process synthesis problems. In particular, we seek to contribute to this increasingly exciting area of chemical process modeling by addressing the following potentially important issues: (a) how the formulation of design specifications in a mixed-logical-and-integer optimization model can be employed in a synthesis problem to enrich the problem representation by incorporating past design experience, engineering knowledge, and heuristics; and (b) how structural specifications on the interconnectivity relationships by space (states) and by function (tasks) in a superstructure should be properly formulated within a mixed-integer linear programming (MILP) model. The proposed modeling technique is illustrated on a case study involving the alternative processing routes of naphtha, in which significant improvement in the solution quality is obtained.Keywords: Mixed-integer linear programming (MILP), petroleum refinery, process synthesis, superstructure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17287444 A Study of Factors Influencing the Improvement of Technology Business Incubator's Effectiveness: An Explanatory Model
Authors: Alireza Ghasemizad
Abstract:
In Both developed and developing countries, governments play a basic role in making policies, programs and instruments which support the development of micro, small and medium enterprises. One of the mechanisms employed to nurture small firms for more than two decades is business incubation. One of the mechanisms employed to nurture small firms for more than two decades is technology business incubation. The main aim of this research was to establish influencing factors in Technology Business Incubator's effectiveness and their explanatory model. Therefore, among 56 Technology Business Incubators in Iran, 32 active incubators were selected and by stratified random sampling, 528 start-ups were chosen. The validity of research questionnaires was determines by expert consensus, item analysis and factor analysis; and their reliability calculated by Cronbach-s alpha. Data analysis was then made through SPSS and LISREL soft wares. Both organizational procedures and entrepreneurial behaviors were the meaningful mediators. Organizational procedures with (P < .01, β =0.45) was stronger mediator for the improvement of Technology Business Incubator's effectiveness comparing to entrepreneurial behavior with (P < .01, β =0.36).Keywords: Technology, Incubators, Effectiveness, Explanatorymodel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20317443 Analysis and Prototyping of Biological Systems: the Abstract Biological Process Model
Authors: Antonio Di Leva, Roberto Berchi, Gianpiero Pescarmona, Michele Sonnessa
Abstract:
The aim of a biological model is to understand the integrated structure and behavior of complex biological systems as a function of the underlying molecular networks to achieve simulation and forecast of their operation. Although several approaches have been introduced to take into account structural and environment related features, relatively little attention has been given to represent the behavior of biological systems. The Abstract Biological Process (ABP) model illustrated in this paper is an object-oriented model based on UML (the standard object-oriented language). Its main objective is to bring into focus the functional aspects of the biological system under analysis.Keywords: Biological processes, system dynamics, systemmodeling, UML.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16407442 Analysis of Possible Draught Size of Container Vessels on the Lower Danube
Authors: Todor Bačkalić, Marinko Maslarić, Milosav Georgijević, Sanja Bojić
Abstract:
Presented article outlines a rationale, why it is necessary to develop competence about infrastructure risk in water transport. Climate changes are evident and require special attention and global monitoring. Current risk assessment methods for Inland waterway transport just consider some dramatic events. We present a new method for the assessment of risk and vulnerability of inland waterway transport where river depth represents a crucial part. The analysis of water level changes in the lower Danube was done for two significant periods (1965-1979 and 1998-2012).Keywords: Container ship, draught, probability, the Danube.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1616