Search results for: Bearing capacity factor
1509 Curvature Ductility Factor of Rectangular Sections Reinforced Concrete Beams
Authors: Y. Si Youcef, M. Chemrouk
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The present work presents a method of calculating the ductility of rectangular sections of beams considering nonlinear behavior of concrete and steel. This calculation procedure allows us to trace the curvature of the section according to the bending moment, and consequently deduce ductility. It also allowed us to study the various parameters that affect the value of the ductility. A comparison of the effect of maximum rates of tension steel, adopted by the codes, ACI [1], EC8 [2] and RPA [3] on the value of the ductility was made. It was concluded that the maximum rate of steels permitted by the ACI [1] codes and RPA [3] are almost similar in their effect on the ductility and too high. Therefore, the ductility mobilized in case of an earthquake is low, the inverse of code EC8 [2]. Recommendations have been made in this direction.Keywords: Ductility, beam, reinforced concrete, seismic code, relationship, time bending, resistance, non-linear behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 61931508 Oxidantantioxidant Status in Calves Supplemented with Green Tea Extract
Authors: Ibrahim I. Elshahawy
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The objective of the present study was to investigate the effect of green tea extract on serum oxidant and antioxidant profile, liver and kidney function. 40 Friesian calves are included in this study and allocated into two groups: Group I (n=20) clinically healthy calves showing no clinical abnormalities, not receiving any treatment and served as control; group II (n=20) received green tea extract (GTE) for 30 days. Non-significant changes in blood urea nitrogen (BUN) were detected between groups, on contrary, serum creatinine and activities of liver enzymes aspartate transaminase (AST) and alanine transaminase (ALT) were significantly different between two groups. There were significant increases in the mean values of serum antioxidative parameters (total antioxidant capacity, catalase, superoxide dismutase, reduced glutathione and glutathione peroxidase) in group II. Whereas, the activity of lipid peroxidase significantly decreased in GTE treated calves when compared to control.
Keywords: Green tea extract, antioxidants, oxidants, calves.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11321507 Optical and Double Folding Analysis for 6Li+16O Elastic Scattering
Authors: Abd Elrahman Elgamala, N. Darwish, I. Bondouk, Sh. Hamada
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Available experimental angular distributions for 6Li elastically scattered from 16O nucleus in the energy range 13.0–50.0 MeV are investigated and reanalyzed using optical model of the conventional phenomenological potential and also using double folding optical model of different interaction models: DDM3Y1, CDM3Y1, CDM3Y2, and CDM3Y3. All the involved models of interaction are of M3Y Paris except DDM3Y1 which is of M3Y Reid and the main difference between them lies in the different values for the parameters of the incorporated density distribution function F(ρ). We have extracted the renormalization factor NR for 6Li+16O nuclear system in the energy range 13.0–50.0 MeV using the aforementioned interaction models.
Keywords: Elastic scattering, optical model, folding potential, density distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5501506 An Evaluation of a Psychotherapeutic Service for Engineering Students: The Role of Race, Gender and Language
Authors: Nazeema Ahmed
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Mental health in higher education has received increasing attention over the past few decades. The high academic demands of the engineering degree, coupled with students’ mental health challenges, have led to higher education institutions offering psychotherapeutic services to students. This paper discusses an evaluation of the psychotherapy service at the University of Cape Town. The aim was to determine (i) the efficacy of the service; and (ii) the impact of race, gender, and language of the therapist on the students’ therapeutic process. An online survey was sent to 109 students who attended psychotherapy. The majority expressed favorable experiences of psychotherapy, with reports of increased capacity to engage with their academic work. Most students did not experience the gender, race, or language of the psychologists to be barriers to their therapy. The findings point to a need for ongoing psychological support for students.Keywords: Psychotherapy, efficacy, engineering, education.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9471505 Effects of used Engine Oil in Reinforced Concrete Beams: The Structural Behaviour
Authors: S.C. Chin, N. Shafiq, M.F. Nuruddin
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In the modern construction practices, industrial wastes or by-products are largely used as raw materials in cement and concrete. These impart many benefits to the environment and bringabout an economic impact because the cost of waste disposal is constantly increasing due to strict environmental regulations. It was reported in literature that the leakage of oil onto concrete element in older cement grinding unit resulted in concrete with greater resistance to freezing and thawing. This effect was thought to be similar to adding an air-entraining chemical admixture to concrete. This paper presents an investigation on the load deflection behaviour and crack patterns of reinforced concrete (RC) beams subjected to four point loading. Ten 120x260x1900 mm beams were cast with 100% ordinary Portland cement (OPC) concrete, 20% fly ash (FA) and 20% rice husk ash (RHA) blended cement concrete. 0.15% dosage of admixtures (used engine oil, new engine oil, and superplasticizer) was used throughout the experiment. Results show that OPC and OPC/RHA RC beams containing used engine oil and superplasticizer exhibit higher capacity, 18-26% than their corresponding control mix.Keywords: by-products, RC beams, superplasticizer, used engine oil
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30881504 Temperature Profile Modelling in Flexible Pavement Design
Authors: Csaba Tóth, Éva Lakatos, László Pethő, Seoyoung Cho
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The temperature effect on asphalt pavement structure is a crucial factor at the design stage. In this paper, by applying the German guidelines for temperature along the asphalt depth is estimated. The aim is to consider temperature profiles in different seasons in numerical modelling. The model is built with an elastic and isotropic solid element with 19 subdivisions of asphalt layers to reflect the temperature variation. Comparison with the simple three-layer pavement system (asphalt layers, base, and subgrade layers) will be followed to see the difference in result without temperature variation along with the depth. Finally, the fatigue life calculation was checked to prove the validity of the methodology of considering the temperature in the numerical modelling.
Keywords: Temperature profile, flexible pavement modelling, finite element method, temperature modelling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5291503 Separation of CO2 Using MFI-Alumina Nanocomposite Hollow Fiber Ion-Exchanged with Alkali Metal Cation
Authors: A. Alshebani, Y. Swesi, S. Mrayed, F. Altaher, I. Musbah
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Cs-type nanocomposite zeolite membrane was successfully synthesized on an alumina ceramic hollow fibre with a mean outer diameter of 1.7 mm; cesium cationic exchange test was carried out inside test module with mean wall thickness of 230 μm and an average crossing pore size smaller than 0.2 μm. Separation factor of n-butane/H2 obtained indicate that a relatively high quality closed to 20. Maxwell-Stefan modeling provides an equivalent thickness lower than 1 µm. To compare the difference an application to CO2/N2 separation has been achieved, reaching separation factors close to (4,18) before and after cation exchange on H-zeolite membrane formed within the pores of a ceramic alumina substrate.
Keywords: MFI membrane, nanocomposite, Ceramic hollow fibre, CO2, Ion-exchange.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20161502 Reduction of Peak Input Currents during Charge Pump Boosting in Monolithically Integrated High-Voltage Generators
Authors: Jan Doutreloigne
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This paper describes two methods for the reduction of the peak input current during the boosting of Dickson charge pumps. Both methods are implemented in the fully integrated Dickson charge pumps of a high-voltage display driver chip for smart-card applications. Experimental results reveal good correspondence with Spice simulations and show a reduction of the peak input current by a factor of 6 during boosting.Keywords: Bi-stable display driver, Dickson charge pump, highvoltage generator, peak current reduction, sub-pump boosting, variable frequency boosting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16281501 Quantitative Analysis of Construction Waste in the City of Novi Sad, Serbia
Authors: Nikola Karanovic, Aleksandar Djuric
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This paper introduces a method of calculating the quantities of construction materials and construction waste on site in city of Novi Sad. In buildings is about 40% of the total weight of materials that are in circulation in the world economic space. The best solution for this waste is to be stored at source, at the point of generation. There are several treatment options for this type of waste, reduction at source, reuse, recycling. Beside its negative effects on the environment, construction waste can be and resource. Novi Sad is divided in 16 single family resident zones and 10 multi family resident zones. For every zone of the city, quantities of used construction materials and construction waste were obtained. Rational use of natural resources is an essential factor in applying the principles of development with savings.Keywords: Construction materials, Construction waste, Novi Sad, Recycling
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16541500 Scheduling for a Reconfigurable Manufacturing System with Multiple Process Plans and Limited Pallets/Fixtures
Authors: Jae-Min Yu, Hyoung-Ho Doh, Ji-Su Kim, Dong-Ho Lee, Sung-Ho Nam
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A reconfigurable manufacturing system (RMS) is an advanced system designed at the outset for rapid changes in its hardware and software components in order to quickly adjust its production capacity and functionally. Among various operational decisions, this study considers the scheduling problem that determines the input sequence and schedule at the same time for a given set of parts. In particular, we consider the practical constraints that the numbers of pallets/fixtures are limited and hence a part can be released into the system only when the fixture required for the part is available. To solve the integrated input sequencing and scheduling problems, we suggest a priority rule based approach in which the two sub-problems are solved using a combination of priority rules. To show the effectiveness of various rule combinations, a simulation experiment was done on the data for a real RMS, and the test results are reported.Keywords: Reconfigurable manufacturing system, scheduling, priority rules, multiple process plans, pallets/fixtures
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18951499 Phytoremediation Potential of Tomato for Cd and Cr Removal from Polluted Soils
Authors: Jahanshah Saleh, Hossein Ghasemi, Ali Shahriari, Faezeh Alizadeh, Yaaghoob Hosseini
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Cadmium and chromium are toxic to most organisms and different mechanisms have been developed for overcoming with the toxic effects of these heavy metals. We studied the uptake and distribution of cadmium and chromium in different organs of tomato (Lycopersicon esculentum L.) plants in nine heavy metal polluted soils in western Hormozgan province, Iran. The accumulation of chromium was in increasing pattern of fruit peel
Keywords: Cadmium, chromium, phytoextraction, phytostabilization, tomato.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18491498 Personalized Learning: An Analysis Using Item Response Theory
Authors: A. Yacob, N. Hj. Ali, M. H. Yusoff, M. Y. MohdSaman, W. M. A. F. W. Hamzah
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Personalized learning becomes increasingly popular which not be restricted by time, place or any other barriers. This study proposes an analysis of Personalized Learning using Item Response Theory which considers course material difficulty and learner ability.The study investigates twenty undergraduate students at TATI University College, who are taking programming subject. By using the IRT,it was found that, finding the most appropriate problem levels to each student include high and low level test items together is not a problem. Thus, the student abilities can be asses more accurately and fairly. Learners who experience more anxiety will affect a heavier cognitive load and receive lower test scores.Instructors are encouraged to provide a supportive learning environment to enhance learning effectiveness because Cognitive Load Theory concerns the limited capacity of the brain to absorb new information.
Keywords: Analysis, Cognitive Load Theory, Item Response Theory, Learning, Motivation, Performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31191497 Smart Grids Cyber Security Issues and Challenges
Authors: Imen Aouini, Lamia Ben Azzouz
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The energy need is growing rapidly due to the population growth and the large new usage of power. Several works put considerable efforts to make the electricity grid more intelligent to reduce essentially energy consumption and provide efficiency and reliability of power systems. The Smart Grid is a complex architecture that covers critical devices and systems vulnerable to significant attacks. Hence, security is a crucial factor for the success and the wide deployment of Smart Grids. In this paper, we present security issues of the Smart Grid architecture and we highlight open issues that will make the Smart Grid security a challenging research area in the future.Keywords: Smart grids, smart meters, home area network, neighbor area network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 39451496 Structural Behaviour of Partially Filled Steel Grid Composite Deck
Authors: Hyun-Seop Shin, Chin-Hyung Lee, Ki-Tae Park
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In order to apply partially filled steel grid composite deck as the horizontal supporting structure of various kinds of infrastructures, the variation of its flexural strength according to design parameters such as cross and longitudinal bars constituting the steel grid and the type of shear connection is evaluated and compared experimentally. The result shows that the design sensitivity of the deck to the spacing of the cross bars is insignificant in the case of structure with low risk of punching failure or without load distribution problem. By means of shear connection composed by transverse rebar and longitudinal bar without additional shear stud bolts, the complete interaction between steel grid and concrete slab is able to be achieved and the composite deck can develop its bending resistance capacity.Keywords: bending strength, composite action, shear connection, steel grid composite deck
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16221495 Real Time Adaptive Obstacle Avoidance in Dynamic Environments with Different D-S
Authors: Mohammad Javad Mollakazemi, Farhad Asadi
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In this paper a real-time obstacle avoidance approach for both autonomous and non-autonomous dynamical systems (DS) is presented. In this approach the original dynamics of the controller which allow us to determine safety margin can be modulated. Different common types of DS increase the robot’s reactiveness in the face of uncertainty in the localization of the obstacle especially when robot moves very fast in changeable complex environments. The method is validated by simulation and influence of different autonomous and non-autonomous DS such as important characteristics of limit cycles and unstable DS. Furthermore, the position of different obstacles in complex environment is explained. Finally, the verification of avoidance trajectories is described through different parameters such as safety factor.
Keywords: Limit cycles, Nonlinear dynamical system, Real time obstacle avoidance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18531494 Functionalized PU Foam for Water Filtration
Authors: Nidal H. Abu-Zahra, Subhashini Gunashekar
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Polyurethane foam is functionalized with Sulfonic acid groups to remove lead ions (Pb2+) from drinking water through a cation exchange process. The synthesis is based on addition polymerization of the -NCO groups of an isocyanate with the –OH groups of a polyol to form the urethane. Toluene-diisocyanateis reacted with Polypropylene glycol to form a linear pre-polymer, which is further polymerized using a chain extender, N, N-bis(2-hydorxyethyl)-2-aminoethane-sulfonic acid (BES). BES acts as a functional group site to exchange Pb2+ ions. A set of experiments was designed to study the effect of various processing parameters on the performance of the synthesized foam. The maximum Pb2+ ion exchange capacity of the foam was found to be 47ppb/g from a 100ppb Pb2+ solution over a period of 60 minutes. A multistage batch filtration process increased the lead removal to 50-54ppb/3g of foam over a period of 90 minutes.
Keywords: Adsorption, Functionalized, Ion exchange, Polyurethane, Sulfonic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30961493 In-situ LDH Formation of Sodium Aluminate Activated Slag
Authors: Tao Liu, Qingliang Yu, H. J. H. Brouwers
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Among the reaction products in the alkali activated ground granulated blast furnace slag (AAS), the layered double hydroxides (LDHs) have a remarkable capacity of chloride and heavy metal ions absorption. The promotion of LDH phases in the AAS matrix can increase chloride resistance. The objective of this study is that using the different dosages of sodium aluminate to activate slag, consequently, promoting the formation of in-situ LDH. The hydration kinetics of the sodium aluminate activated slag (SAAS) was tested by the isothermal calorimetry. Meanwhile, the reaction products were determined by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The sodium hydroxide activated slag is selected as the reference. The results of XRD, TGA, and FTIR showed that the formation of LDH in SAAS is governed by the aluminate dosages.
Keywords: ground granulated blast furnace slag, sodium aluminate activated slag, in-situ LDH formation, chloride absorption
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4861492 Complexity of Mathematical Expressions in Adaptive Multimodal Multimedia System Ensuring Access to Mathematics for Visually Impaired Users
Authors: Ali Awde, Yacine Bellik, Chakib Tadj
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Our adaptive multimodal system aims at correctly presenting a mathematical expression to visually impaired users. Given an interaction context (i.e. combination of user, environment and system resources) as well as the complexity of the expression itself and the user-s preferences, the suitability scores of different presentation format are calculated. Unlike the current state-of-the art solutions, our approach takes into account the user-s situation and not imposes a solution that is not suitable to his context and capacity. In this wok, we present our methodology for calculating the mathematical expression complexity and the results of our experiment. Finally, this paper discusses the concepts and principles applied on our system as well as their validation through cases studies. This work is our original contribution to an ongoing research to make informatics more accessible to handicapped users.Keywords: Adaptive system, intelligent multi-agent system, mathematics for visually-impaired users.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15851491 Stability of Square Plate with Concentric Cutout
Authors: B. S. Jayashankarbabu, Karisiddappa
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The finite element method is used to obtain the elastic buckling load factor for square isotropic plate containing circular, square and rectangular cutouts. ANSYS commercial finite element software had been used in the study. The applied inplane loads considered are uniaxial and biaxial compressions. In all the cases the load is distributed uniformly along the plate outer edges. The effects of the size and shape of concentric cutouts with different plate thickness ratios and the influence of plate edge conditions, such as SSSS, CCCC and mixed boundary condition SCSC on the plate buckling strength have been considered in the analysis.
Keywords: Concentric cutout, Elastic buckling, Finite element method, Inplane loads, Thickness ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32261490 Decentralized Handoff for Microcellular Mobile Communication System using Fuzzy Logic
Authors: G. M. Mir, N. A. Shah, Moinuddin
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Efficient handoff algorithms are a cost-effective way of enhancing the capacity and QoS of cellular system. The higher value of hysteresis effectively prevents unnecessary handoffs but causes undesired cell dragging. This undesired cell dragging causes interference or could lead to dropped calls in microcellular environment. The problems are further exacerbated by the corner effect phenomenon which causes the signal level to drop by 20-30 dB in 10-20 meters. Thus, in order to maintain reliable communication in a microcellular system new and better handoff algorithms must be developed. A fuzzy based handoff algorithm is proposed in this paper as a solution to this problem. Handoff on the basis of ratio of slopes of normal signal loss to the actual signal loss is presented. The fuzzy based solution is supported by comparing its results with the results obtained in analytical solution.Keywords: Slope ratio, handoff, corner effect, fuzzy logic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15141489 Layout Design Optimization of Spars under Multiple Load Cases of the High-Aspect-Ratio Wing
Authors: Yu Li, Jingwu He, Yuexi Xiong
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The spar layout will affect the wing’s stiffness characteristics, and irrational spar arrangement will reduce the overall bending and twisting resistance capacity of the wing. In this paper, the active structural stiffness design theory is used to match the stiffness-center axis position and load-cases under the corresponding multiple flight conditions, in order to achieve better stiffness properties of the wing. The combination of active stiffness method and principle of stiffness distribution is proved to be reasonable supplying an initial reference for wing designing. The optimized layout of spars is eventually obtained, and the high-aspect-ratio wing will have better stiffness characteristics.
Keywords: Active structural stiffness design theory, high-aspect-ratio wing, flight load cases, layout of spars.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11121488 A Framework for the Evaluation of Infrastructures’ Serviceability
Authors: Kyonghoon Kim, Wonyoung Park, Taeil Park
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Aging infrastructures became a serious social problem. This brought out the increased need for the legislation of a new strict guideline for infrastructure management. Although existing guidelines provided basics of how to evaluate and manage the condition of infrastructures, they needed improvements for their evaluation procedures. Most guidelines mainly focused on the structural condition of infrastructures and did not properly reflect service aspects of infrastructures such as performance, public demand, capacity, etc., which were significantly valuable to public. Regardless of the importance, these factors were often neglected in infrastructure evaluations, because they were quite subjective and difficult to quantify in rational manner. Thus, this study proposed a framework to properly identify and evaluate the service indicators. This study showed that service indicators could be grouped into two categories and properly evaluated using AHP and Fuzzy. Overall, proposed framework is expected to assist governmental agency in establishing effective investment strategies for infrastructure improvements.Keywords: Infrastructure, evaluation, serviceability, fuzzy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16621487 Effect of Open Burning on Soil Carbon Stock in Sugarcane Plantation in Thailand
Authors: Wilaiwan Sornpoon, Sébastien Bonnet, Savitri Garivait
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Open burning of sugarcane fields is recognized to have a negative impact on soil by degrading its properties, especially soil organic carbon (SOC) content. Better understating the effect of open burning on soil carbon dynamics is crucial for documenting the carbon sequestration capacity of agricultural soils. In this study, experiments to investigate soil carbon stocks under burned and unburned sugarcane plantation systems in Thailand were conducted. The results showed that cultivation fields without open burning during 5 consecutive years enabled to increase the SOC content at a rate of 1.37 Mg ha-1y-1. Also it was found that sugarcane fields burning led to about 15% reduction of the total carbon stock in the 0-30 cm soil layer. The overall increase in SOC under unburned practice is mainly due to the large input of organic material through the use of sugarcane residues.
Keywords: Soil organic carbon, Soil inorganic carbon, Carbon sequestration, Open burning, Sugarcane.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33841486 Analysis of Scattering Behavior in the Cavity of Phononic Crystals with Archimedean Tilings
Authors: Yi-Hua Chen, Hsiang-Wen Tang, I-Ling Chang, Lien-Wen Chen
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The defect mode of two-dimensional phononic crystals with Archimedean tilings was explored in the present study. Finite element method and supercell method were used to obtain dispersion relation of phononic crystals. The simulations of the acoustic wave propagation within phononic crystals are demonstrated. Around the cavity which is created by removing several cylinders in the perfect Archimedean tilings, whispering-gallery mode (WGM) can be observed. The effects of the cavity geometry on the WGM modes are investigated. The WGM modes with high Q-factor and high cavity pressure can be obtained by phononic crystals with Archimedean tilings.
Keywords: Defect mode, Archimedean tilings, phononic crystals, whispering- gallery modes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11401485 Electrospinning and Characterization of Silk Fibroin/Gelatin Nanofibre Mats
Authors: S. Mohammadzadehmoghadam, Y. Dong
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In this study, Bombyx mori silk fibroin/gelatin (SF/GT) nanocomposite with different GT ratio (SF/GT 100/0, 90/10 and 70/30) were prepared by electrospinning process and crosslinked with glutaraldehyde (GA) vapor. Properties of crosslinked SF/GT nanocomposites were investigated by scanning electron microscopy (SEM), mechanical test, water uptake capacity (WUC) and porosity. From SEM images, it was found that fiber diameter increased as GT content increased. The results of mechanical test indicated that the SF/GT 70/30 nanocomposites had both the highest Young’s modulus of 342 MPa and the highest tensile strength of about 14 MPa. However, porosity and WUC decreased from 62% and 405% for pristine SF to 47% and 232% for SF/GT 70/30, respectively. This behavior can be related to higher degree of crosslinking as GT ratio increased which altered the structure and physical properties of scaffolds. This study showed that incorporation of GT into SF nanofibers can enhance mechanical properties of resultant nanocomposite, but the GA treatment should be optimized to control and fine-tune other properties to warrant their biomedical application.Keywords: Electrospinning, gelatin, mechanical properties, nanocomposites, silk fibroin.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8911484 Adsorption of Ferrous and Ferric Ions in Aqueous and Industrial Effluent onto Pongamia pinnata Tree Bark
Authors: M. Mamatha, H. B. Aravinda, E. T. Puttaiah, S. Manjappa
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One of the causes of water pollution is the presence of heavy metals in water. In the present study, an adsorbent prepared from the raw bark of the Pongamia pinnata tree is used for the removal of ferrous or ferric ions from aqueous and waste water containing heavy metals. Adsorption studies were conducted at different pH, concentration of metal ion, amount of adsorbent, contact time, agitation and temperature. The Langmuir and Freundlich adsorption isotherm models were applied for the results. The Langmuir isotherms were best fitted by the equilibrium data. The maximum adsorption was found to 146mg/g in waste water at a temperature of 30°C which is in agreement as comparable to the adsorption capacity of different adsorbents reported in literature. Pseudo second order model best fitted the adsorption of both ferrous and ferric ions.
Keywords: Adsorption, Adsorption isotherms, Heavy metals, Industrial effluents.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32511483 Analyzing Keyword Networks for the Identification of Correlated Research Topics
Authors: Thiago M. R. Dias, Patrícia M. Dias, Gray F. Moita
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The production and publication of scientific works have increased significantly in the last years, being the Internet the main factor of access and distribution of these works. Faced with this, there is a growing interest in understanding how scientific research has evolved, in order to explore this knowledge to encourage research groups to become more productive. Therefore, the objective of this work is to explore repositories containing data from scientific publications and to characterize keyword networks of these publications, in order to identify the most relevant keywords, and to highlight those that have the greatest impact on the network. To do this, each article in the study repository has its keywords extracted and in this way the network is characterized, after which several metrics for social network analysis are applied for the identification of the highlighted keywords.Keywords: Extraction and data integration, bibliometrics, scientometrics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6951482 Generating Concept Trees from Dynamic Self-organizing Map
Authors: Norashikin Ahmad, Damminda Alahakoon
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Self-organizing map (SOM) provides both clustering and visualization capabilities in mining data. Dynamic self-organizing maps such as Growing Self-organizing Map (GSOM) has been developed to overcome the problem of fixed structure in SOM to enable better representation of the discovered patterns. However, in mining large datasets or historical data the hierarchical structure of the data is also useful to view the cluster formation at different levels of abstraction. In this paper, we present a technique to generate concept trees from the GSOM. The formation of tree from different spread factor values of GSOM is also investigated and the quality of the trees analyzed. The results show that concept trees can be generated from GSOM, thus, eliminating the need for re-clustering of the data from scratch to obtain a hierarchical view of the data under study.
Keywords: dynamic self-organizing map, concept formation, clustering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14591481 A Study of Recycle Materials to Develop for Auto Part
Authors: Sittichai Kaewkuekool, Vanchai Laemlaksakul
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At the present, auto part industries have become higher challenge in strategy market. As this consequence, manufacturers need to have better response to customers in terms of quality, cost, and delivery time. Moreover, they need to have a good management in factory to comply with international standard maximum capacity and lower cost. This would lead companies to have to order standard part from aboard and become the major cost of inventory. The development of auto part research by recycling materials experiment is to compare the auto parts from recycle materials to international auto parts (CKD). Factors studied in this research were the recycle material ratios of PU-foam, felt, and fabric. Results of recycling materials were considered in terms of qualities and properties on the parameters such as weight, sound absorption, water absorption, tensile strength, elongation, and heat resistance with the CKD. The results were showed that recycling materials would be used to replace for the CKD.
Keywords: International auto parts, recycling materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20741480 Thermodynamic Performance of a Combined Power and Ejector Refrigeration Cycle
Authors: Hyung Jong Ko, Kyoung Hoon Kim
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In this study thermodynamic performance analysis of a combined organic Rankine cycle and ejector refrigeration cycle is carried out for use of low-grade heat source in the form of sensible energy. Special attention is paid to the effects of system parameters including the turbine inlet temperature and turbine inlet pressure on the characteristics of the system such as ratios of mass flow rate, net work production, and refrigeration capacity as well as the coefficient of performance and exergy efficiency of the system. Results show that for a given source the coefficient of performance increases with increasing of the turbine inlet pressure. However, the exergy efficiency has an optimal condition with respect to the turbine inlet pressure.
Keywords: Coefficient of performance, ejector refrigeration cycle, exergy efficiency, low-grade energy, organic rankine cycle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2503