Search results for: internal mixing atomizer
508 Role of Dispersion of Multiwalled Carbon Nanotubes on Compressive Strength of Cement Paste
Authors: Jyoti Bharj, Sarabjit Singh, Subhash Chander, Rabinder Singh
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The outstanding mechanical properties of Carbon nanotubes (CNTs) have generated great interest for their potential as reinforcements in high performance cementitious composites. The main challenge in research is the proper dispersion of carbon nanotubes in the cement matrix. The present work discusses the role of dispersion of multiwalled carbon nanotubes (MWCNTs) on the compressive strength characteristics of hydrated Portland IS 1489 cement paste. Cement-MWCNT composites with different mixing techniques were prepared by adding 0.2% (by weight) of MWCNTs to Portland IS 1489 cement. Rectangle specimens of size approximately 40mm × 40mm ×160mm were prepared and curing of samples was done for 7, 14, 28 and 35days. An appreciable increase in compressive strength with both techniques; mixture of MWCNTs with cement in powder form and mixture of MWCNTs with cement in hydrated form 7 to 28 days of curing time for all the samples was observed.
Keywords: Carbon Nanotubes, Portland Cement, Composite, Compressive Strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3132507 Fuzzy Voting in Internal Elections of Educational and Party Organizations
Authors: R. Hosseingholizadeh
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This article presents a method for elections between the members of a group that is founded by fuzzy logic. Linguistic variables are objects for decision on election cards and deduction is based on t-norms and s-norms. In this election-s method election cards are questionnaire. The questionnaires are comprised of some questions with some choices. The choices are words from natural language. Presented method is accompanied by center of gravity (COG) defuzzification added up to a computer program by MATLAB. Finally the method is illustrated by solving two examples; choose a head for a research group-s members and a representative for students.
Keywords: fuzzy election, fuzzy electoral card, fuzzy inference, questionnaire.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1421506 Prediction of Slump in Concrete using Artificial Neural Networks
Authors: V. Agrawal, A. Sharma
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High Strength Concrete (HSC) is defined as concrete that meets special combination of performance and uniformity requirements that cannot be achieved routinely using conventional constituents and normal mixing, placing, and curing procedures. It is a highly complex material, which makes modeling its behavior a very difficult task. This paper aimed to show possible applicability of Neural Networks (NN) to predict the slump in High Strength Concrete (HSC). Neural Network models is constructed, trained and tested using the available test data of 349 different concrete mix designs of High Strength Concrete (HSC) gathered from a particular Ready Mix Concrete (RMC) batching plant. The most versatile Neural Network model is selected to predict the slump in concrete. The data used in the Neural Network models are arranged in a format of eight input parameters that cover the Cement, Fly Ash, Sand, Coarse Aggregate (10 mm), Coarse Aggregate (20 mm), Water, Super-Plasticizer and Water/Binder ratio. Furthermore, to test the accuracy for predicting slump in concrete, the final selected model is further used to test the data of 40 different concrete mix designs of High Strength Concrete (HSC) taken from the other batching plant. The results are compared on the basis of error function (or performance function).Keywords: Artificial Neural Networks, Concrete, prediction ofslump, slump in concrete
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3595505 Impact of Zn/Cr Ratio on ZnCrOx-SAPO-34 Bifunctional Catalyst for Direct Conversion of Syngas to Light Olefins
Authors: Yuxuan Huang, Weixin Qian, Hongfang Ma, Haitao Zhang, Weiyong Ying
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Light olefins are important building blocks for chemical industry. Direct conversion of syngas to light olefins has been investigated for decades. Meanwhile, the limit for light olefins selectivity described by Anderson-Schulz-Flory (ASF) distribution model is still a great challenge to conventional Fischer-Tropsch synthesis. The emerging strategy called oxide-zeolite concept (OX-ZEO) is a promising way to get rid of this limit. ZnCrOx was prepared by co-precipitation method and (NH4)2CO3 was used as precipitant. SAPO-34 was prepared by hydrothermal synthesis, and Tetraethylammonium hydroxide (TEAOH) was used as template, while silica sol, pseudo-boehmite, and phosphoric acid were Al, Si and P source, respectively. The bifunctional catalyst was prepared by mechanical mixing of ZnCrOx and SAPO-34. Catalytic reactions were carried out under H2/CO=2, 380 ℃, 1 MPa and 6000 mL·gcat-1·h-1 in a fixed-bed reactor with a quartz lining. Catalysts were characterized by XRD, N2 adsorption-desorption, NH3-TPD, H2-TPR, and CO-TPD. The addition of Al as structure promoter enhances CO conversion and selectivity to light olefins. Zn/Cr ratio, which decides the active component content and chemisorption property of the catalyst, influences CO conversion and selectivity to light olefins at the same time. C2-4= distribution of 86% among hydrocarbons at CO conversion of 14% was reached when Zn/Cr=1.5.
Keywords: Light olefins, OX-ZEO, syngas, ZnCrOx.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1019504 Methodology Issues and Design Approach of VLE on Mathematical Concepts Acquisition within Secondary Education in England
Authors: Aaron A. R. Nwabude
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This study used positivist quantitative approach to examine the mathematical concepts acquisition of- KS4 (14-16) Special Education Needs (SENs) students within the school sector education in England. The research is based on a pilot study and the design is completely holistic in its approach with mixing methodologies. The study combines the qualitative and quantitative methods of approach in gathering formative data for the design process. Although, the approach could best be described as a mix method, fundamentally with a strong positivist paradigm, hence my earlier understanding of the differentiation of the students, student – teacher body and the various elements of indicators that is being measured which will require an attenuated description of individual research subjects. The design process involves four phases with five key stages which are; literature review and document analysis, the survey, interview, and observation; then finally the analysis of data set. The research identified the need for triangulation with Reid-s phases of data management providing scaffold for the study. The study clearly identified the ideological and philosophical aspects of educational research design for the study of mathematics by the special education needs (SENs) students in England using the virtual learning environment (VLE) platform.
Keywords: VLE, Special Education Needs, Key stage4, School, Mathematics, Concepts Acquisition
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1977503 Study the Behavior of Different Composite Short Columns (DST) with Prismatic Sections under Bending Load
Authors: V. Sadeghi Balkanlou, M. Reza Bagerzadeh Karimi, A. Hasanbakloo, B. Bagheri Azar
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In this paper, the behavior of different types of DST columns has been studied under bending load. Briefly, composite columns consist of an internal carbon steel tube and an external stainless steel wall that the between the walls are filled with concrete. Composite columns are expected to combine the advantages of all three materials and have the advantage of high flexural stiffness of CFDST columns. In this research, ABAQUS software is used for finite element analysis then the results of ultimate strength of the composite sections are illustrated.
Keywords: DST, Stainless steel, carbon steel, ABAQUS, Straigh Columns, Tapered Columns.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3519502 Real-Time Detecting Concentration of Mycobacterium Tuberculosis by CNTFET Biosensor
Authors: Hsiao-Wei Wang, Jung-Tang Huang, Chun-Chiang Lin
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Aptamers are useful tools in microorganism researches, diagnoses, and treatment. Aptamers are specific target molecules formed by oligonucleic acid molecules, and are not decomposed by alcohol. Aptamers used to detect Mycobacterium tuberculosis (MTB) have been proved to have specific affinity to the outer membrane proteins of MTB. This article presents a biosensor chip set with aptamers for early detection of MTB with high specificity and sensitivity, even in very low concentration. Meanwhile, we have already made a modified hydrophobic facial mask module with internal rendering hydrophobic for effectively collecting M. tuberculosis.
Keywords: Aptamers, CNTFET, Mycobacterium tuberculosis, early detection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1998501 Good Practices in the Development of the Erasmus Mundus Master program in Color in Informatics and Media Technology
Authors: J. Hardeberg, J. Hernandez-Andrès, J. L. Nieves, M. Hauta-Kasari, J. Parkkinen, A. Trémeau
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The main objective of this paper is to identify and disseminate good practice in quality assurance and enhancement as well as in teaching and learning at master level. This paper focuses on the experience of the Erasmus Mundus Master program CIMET (Color in Informatics and Media Technology). Amongst topics covered, we discuss the adjustments necessary to a curriculum designed for excellent international students and their preparation for a global labor market.Keywords: Good practice, internal quality systems, innovationsin curriculum design, challenges of internationalization
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1463500 Towards a Computational Model of Consciousness: Global Abstraction Workspace
Authors: Halim Djerroud, Arab Ali Cherif
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We assume that conscious functions are implemented automatically. In other words that consciousness as well as the non-consciousness aspect of human thought, planning and perception, are produced by biologically adaptive algorithms. We propose that the mechanisms of consciousness can be produced using similar adaptive algorithms to those executed by the mechanism. In this paper, we present a computational model of consciousness, the ”Global Abstraction Workspace” which is an internal environmental modelling perceived as a multi-agent system. This system is able to evolve and generate new data and processes as well as actions in the environment.Keywords: Artificial consciousness, cognitive architecture, global abstraction workspace, mutli-agents system.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1583499 Sediment Wave and Cyclic Steps as Mechanism for Sediment Transport in Submarine Canyons Thalweg
Authors: Taiwo Olusoji Lawrence, Peace Mawo Aaron
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Seismic analysis of bedforms has proven to be one of the best ways to study deepwater sedimentary features. Canyons are known to be sediment transportation conduit. Sediment wave are large-scale depositional bedforms in various parts of the world's oceans formed predominantly by suspended load transport. These undulating objects usually have tens of meters to a few kilometers in wavelength and a height of several meters. Cyclic steps have long long-wave upstream-migrating bedforms confined by internal hydraulic jumps. They usually occur in regions with high gradients and slope breaks. Cyclic steps and migrating sediment waves are the most common bedform on the seafloor. Cyclic steps and related sediment wave bedforms are significant to the morpho-dynamic evolution of deep-water depositional systems architectural elements, especially those located along tectonically active margins with high gradients and slope breaks that can promote internal hydraulic jumps in turbidity currents. This report examined sedimentary activities and sediment transportation in submarine canyons and provided distinctive insight into factors that created a complex seabed canyon system in the Ceara Fortaleza basin Brazilian Equatorial Margin (BEM). The growing importance of cyclic steps made it imperative to understand the parameters leading to their formation, migration, and architecture as well as their controls on sediment transport in canyon thalweg. We extracted the parameters of the observed bedforms and evaluated the aspect ratio and asymmetricity. We developed a relationship between the hydraulic jump magnitude, depth of the hydraulic fall and the length of the cyclic step therein. It was understood that an increase in the height of the cyclic step increases the magnitude of the hydraulic jump and thereby increases the rate of deposition on the preceding stoss side. An increase in the length of the cyclic steps reduces the magnitude of the hydraulic jump and reduces the rate of deposition at the stoss side. Therefore, flat stoss side was noticed at most preceding cyclic step and sediment wave.Keywords: Ceara Fortaleza, sediment wave, cyclic steps, submarine canyons.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 827498 Characterizations of Star-Shaped, L-Convex, and Convex Polygons
Authors: Thomas Shermer, Godfried T. Toussaint
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A chord of a simple polygon P is a line segment [xy] that intersects the boundary of P only at both endpoints x and y. A chord of P is called an interior chord provided the interior of [xy] lies in the interior of P. P is weakly visible from [xy] if for every point v in P there exists a point w in [xy] such that [vw] lies in P. In this paper star-shaped, L-convex, and convex polygons are characterized in terms of weak visibility properties from internal chords and starshaped subsets of P. A new Krasnoselskii-type characterization of isothetic star-shaped polygons is also presented.Keywords: Convex polygons, L-convex polygons, star-shaped polygons, chords, weak visibility, discrete and computational geometry
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2342497 Weakened Vortex Shedding from a Rotating Cylinder
Authors: Sharul S. Dol
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An experimental study of the turbulent near wake of a rotating circular cylinder was made at a Reynolds number of 2000 for velocity ratios, λ between 0 and 2.7. Particle image velocimetry data are analyzed to study the effects of rotation on the flow structures behind the cylinder. The results indicate that the rotation of the cylinder causes significant changes in the vortex formation. Kármán vortex shedding pattern of alternating vortices gives rise to strong periodic fluctuations of a vortex street for λ < 2.0. Alternate vortex shedding is weak and close to being suppressed at λ = 2.0 resulting a distorted street with vortices of alternating sense subsequently being found on opposite sides. Only part of the circulation is shed due to the interference in the separation point, mixing in the base region, re-attachment, and vortex cut-off phenomenon. Alternating vortex shedding pattern diminishes and completely disappears when the velocity ratio is 2.7. The shed vortices are insignificant in size and forming a single line of vortex street. It is clear that flow asymmetries will deteriorate vortex shedding, and when the asymmetries are large enough, total inhibition of a periodic street occurs.
Keywords: Circulation, particle image velocimetry, rotating circular cylinder, smoke-wire flow visualization, Strouhal number, vortex shedding, vortex street.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2863496 Benefits from a SMED Application in a Punching Machine
Authors: Eric Costa, Sara Bragança, Rui Sousa, Anabela Alves
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This paper presents an application of the Single-Minute Exchange of Die (SMED) methodology to a turret punching machine in an elevators company, in Portugal. The work was developed during five months, in the ambit of a master thesis in Industrial Engineering and Management. The Lean Production tool SMED was applied to reduce setup times in order to improve the production flexibility of the machine. The main results obtained were a reduction of 64% in setup time (from 15.1 to 5.4min), 50% in work-in-process amount (from 12.8 to 6.4 days) and 99% in the distance traveled by the operator during the internal period (from 136.7 to 1.7m). These improvements correspond to gains of about €7,315.38 per year.
Keywords: Lean production, setup process, SMED.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4082495 Spatio-Temporal Patterns and Dynamics in Motion of Pathogenic Spirochetes: Implications toward Virulence and Treatment of Leptospirosis
Authors: R. Amornmaneekul, S. Chadsuthi, D. Triampo, W. Triampo
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We apply a particle tracking technique to track the motion of individual pathogenic Leptospira. We observe and capture images of motile Leptospira by means of CCD and darkfield microscope. Image processing, statistical theories and simulations are used for data analysis. Based on trajectory patterns, mean square displacement, and power spectral density characteristics, we found that the motion modes are most likely to be directed motion mode (70%) and the rest are either normal diffusion or unidentified mode. Our findings may support the fact that why leptospires are very well efficient toward targeting internal tissues as a result of increase in virulence factor.
Keywords: Leptospirosis, spirochetes, patterns, motion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1569494 Heat Transfer from a Cylinder in Cross-Flow of Single and Multiphase Flows
Authors: F. A. Hamad, S. He
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In this paper, the average heat transfer characteristics for a cross flow cylinder of 16 mm diameter in a vertical pipe has been studied for single-phase flow (water/oil) and multicomponent (non-boiling) flow (water-air, water-oil, oil-air and water-oil-air). The cylinder is uniformly heated by electrical heater placed at the centre of the element. The results show that the values of average heat transfer coefficients for water are around four times the values for oil flow. Introducing air as a second phase with water has very little effect on heat transfer rate, while the heat transfer increased by 70% in case of oil. For water–oil flow, the heat transfer coefficient values are reflecting the percentage of water up to 50%, but increasing the water more than 50% leads to a sharp increase in the heat transfer coefficients to become close to the values of pure water. The enhancement of heat transfer by mixing two phases may be attributed to the changes in flow structure near to cylinder surface which lead to thinner boundary layer and higher turbulence. For three-phase flow, the heat transfer coefficients for all cases fall within the limit of single-phase flow of water and oil and are very close to pure water values. The net effect of the turbulence augmentation due to the introduction of air and the attenuation due to the introduction of oil leads to a thinner boundary layer of oil over the cylinder surface covered by a mixture of water and air bubbles.Keywords: Circular cylinder, cross-flow, heat transfer, multicomponent multiphase flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2179493 Production of Composite Materials by Mixing Chromium-Rich Ash and Soda-Lime Glass Powder: Mechanical Properties and Microstructure
Authors: Savvas Varitis, Panagiotis Kavouras, George Vourlias, Eleni Pavlidou, Theodoros Karakostas, Philomela Komninou
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A chromium-loaded ash originating from incineration of tannery sludge under anoxic conditions was mixed with low grade soda-lime glass powder coming from commercial glass bottles. The relative weight proportions of ash over glass powder tested were 30/70, 40/60 and 50/50. The solid mixtures, formed in green state compacts, were sintered at the temperature range of 800o C up to 1200o C. The resulting products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDXS) and micro-indentation. The above methods were employed to characterize the various phases, microstructure and hardness of the produced materials. Thermal treatment at 800o C and 1000o C produced opaque ceramic products composed of a variety of chromium-containing and chromium-free crystalline phases. Thermal treatment at 1200o C gave rise to composite products, where only chromium-containing crystalline phases were detected. Hardness results suggest that specific products are serious candidates for structural applications.
Keywords: Chromium-rich tannery residues, glass-ceramic materials, mechanical properties, microstructure
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1865492 The Effect of Acrylic Gel Grouting on Groundwater in Porous Media
Authors: S. Wagner, C. Boley, Y. Forouzandeh
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When digging excavations, groundwater bearing layers are often encountered. In order to allow anhydrous excavation, soil groutings are carried out, which form a water-impermeable layer. As it is injected into groundwater areas, the effects of the materials used on the environment must be known. Developing an eco-friendly, economical and low viscous acrylic gel which has a sealing effect on groundwater is therefore a significant task. At this point the study begins. Basic investigations with the rheometer and a reverse column experiment have been performed with different mixing ratios of an acrylic gel. A dynamic rheology study was conducted to determine the time at which the gel still can be processed and the maximum gel strength is reached. To examine the effect of acrylic gel grouting on determine the parameters pH value, turbidity, electric conductivity, and total organic carbon on groundwater, an acrylic gel was injected in saturated sand filled the column. The structure was rinsed with a constant flow and the eluate was subsequently examined. The results show small changes in pH values and turbidity but there is a dependency between electric conductivity and total organic carbon. The curves of the two parameters react at the same time, which means that the electrical conductivity in the eluate can be measured constantly until the maximum is reached and only then must total organic carbon (TOC) samples be taken.
Keywords: Acrylic gel grouting, dynamic rheology study, electric conductivity, total organic carbon.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 542491 Texture Observation of Bending by XRD and EBSD Method
Authors: Takashi Sakai, Yuri Shimomura
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The crystal orientation is a factor that affects the microscopic material properties. Crystal orientation determines the anisotropy of the polycrystalline material. And it is closely related to the mechanical properties of the material. In this paper, for pure copper polycrystalline material, two different methods; X-Ray Diffraction (XRD) and Electron Backscatter Diffraction (EBSD); and the crystal orientation were analyzed. In the latter method, it is possible that the X-ray beam diameter is thicker as compared to the former, to measure the crystal orientation macroscopically relatively. By measurement of the above, we investigated the change in crystal orientation and internal tissues of pure copper.
Keywords: Bending, electron backscatter diffraction, X-ray diffraction, microstructure, IPF map, orientation distribution function.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1755490 In Search of the Meaning of Entrepreneurship
Authors: H. Fabian Weber, Betina Szkudlarek
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The following study aims to outline, whether the perceptions of entrepreneurs about their entrepreneurial activities and the underlying meanings of their activities are universal or whether they vary systematically across cultures. In contrast to previous studies, the phenomenographical approach and the resulting findings of this study provide new insights into what constitutes entrepreneurship by drawing an inference from the perceptions of entrepreneurs in the United States and in Germany. Culture is shown to have an important impact on entrepreneurship, since the underlying meanings of entrepreneurship vary significantly among the two sample groups. Furthermore, the study sheds more light on the culturally contingent 'why' of entrepreneurship by looking at the internal motivations of individuals instead of exclusively focusing on character traits or external influences of the respective economic environments.Keywords: Cross-Cultural Management, Entrepreneurship, Phenomenography, Qualitative Research.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3156489 The Morphology of Sri Lankan Text Messages
Authors: Chamindi Dilkushi Senaratne
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Communicating via a text or an SMS (Short Message Service) has become an integral part of our daily lives. With the increase in the use of mobile phones, text messaging has become a genre by itself worth researching and studying. It is undoubtedly a major phenomenon revealing language change. This paper attempts to describe the morphological processes of text language of urban bilinguals in Sri Lanka. It will be a typological study based on 500 English text messages collected from urban bilinguals residing in Colombo. The messages are selected by categorizing the deviant forms of language use apparent in text messages. These stylistic deviations are a deliberate skilled performance by the users of the language possessing an in-depth knowledge of linguistic systems to create new words and thereby convey their linguistic identity and individual and group solidarity via the message. The findings of the study solidifies arguments that the manipulation of language in text messages is both creative and appropriate. In addition, code mixing theories will be used to identify how existing morphological processes are adapted by bilingual users in Sri Lanka when texting. The study will reveal processes such as omission, initialism, insertion and alternation in addition to other identified linguistic features in text language. The corpus reveals the most common morphological processes used by Sri Lankan urban bilinguals when sending texts.Keywords: Bilingual, deviations, morphology, texts.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1976488 Rheological Modeling for Shape-Memory Thermoplastic Polymers
Authors: H. Hosseini, B. V. Berdyshev, I. Iskopintsev
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This paper presents a rheological model for producing shape-memory thermoplastic polymers. Shape-memory occurs as a result of internal rearrangement of the structural elements of a polymer. A non-linear viscoelastic model was developed that allows qualitative and quantitative prediction of the stress-strain behavior of shape-memory polymers during heating. This research was done to develop a technique to determine the maximum possible change in size of shape-memory products during heating. The rheological model used in this work was particularly suitable for defining process parameters and constructive parameters of the processing equipment.Keywords: Elastic deformation, heating, shape-memory polymers, stress-strain behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1766487 Experimental Investigation on the Effect of Ultrasonication on Dispersion and Mechanical Performance of Multi-Wall Carbon Nanotube-Cement Mortar Composites
Authors: S. Alrekabi, A. Cundy, A. Lampropoulos, I. Savina
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Due to their remarkable mechanical properties, multi-wall carbon nanotubes (MWCNTs) are considered by many researchers to be a highly promising filler and reinforcement agent for enhanced performance cementitious materials. Currently, however, achieving an effective dispersion of MWCNTs remains a major challenge in developing high performance nano-cementitious composites, since carbon nanotubes tend to form large agglomerates and bundles as a consequence of Van der Waals forces. In this study, effective dispersion of low concentrations of MWCNTs at 0.01%, 0.025%, and 0.05% by weight of cement in the composite was achieved by applying different sonication conditions in combination with the use of polycarboxylate ether as a surfactant. UV-Visible spectroscopy and Transmission electron microscopy (TEM) were used to assess the dispersion of MWCNTs in water, while the dispersion states of MWCNTs within the cement composites and their surface interactions were examined by scanning electron microscopy (SEM). A high sonication intensity applied over a short time period significantly enhanced the dispersion of MWCNTs at initial mixing stages, and 0.025% of MWCNTs wt. of cement, caused 86% and 27% improvement in tensile strength and compressive strength respectively, compared with a plain cement mortar.Keywords: Dispersion, multiwall carbon nanotubes, mechanical performance, sonication conditions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1875486 Real-Time Digital Oscilloscope Implementation in 90nm CMOS Technology FPGA
Authors: Nasir Mehmood, Jens Ogniewski, Vinodh Ravinath
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This paper describes the design of a real-time audiorange digital oscilloscope and its implementation in 90nm CMOS FPGA platform. The design consists of sample and hold circuits, A/D conversion, audio and video processing, on-chip RAM, clock generation and control logic. The design of internal blocks and modules in 90nm devices in an FPGA is elaborated. Also the key features and their implementation algorithms are presented. Finally, the timing waveforms and simulation results are put forward.Keywords: CMOS, VLSI, Oscilloscope, Field Programmable Gate Array (FPGA), VHDL, Video Graphics Array (VGA)
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3082485 Elastic-Plastic Transition in a Thin Rotating Disc with Inclusion
Authors: Pankaj, Sonia R. Bansal
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Stresses for the elastic-plastic transition and fully plastic state have been derived for a thin rotating disc with inclusion and results have been discussed numerically and depicted graphically. It has been observed that the rotating disc with inclusion and made of compressible material requires lesser angular speed to yield at the internal surface whereas it requires higher percentage increase in angular speed to become fully plastic as compare to disc made of incompressible material.Keywords: Angular speed, Elastic-Plastic, Inclusion, Rotatingdisc, Stress, Transition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1717484 Effect of Marginal Quality Groundwater on Yield of Cotton Crop and Soil Salinity Status
Authors: Qureshi, A. L., Mahessar A. A., Dashti, R. K., Yasin S. M.
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In this paper, effect of marginal quality groundwater on yield of cotton crop and soil salinity was studied. In this connection, three irrigation treatments each with four replications were applied. These treatments were i) use of canal water (T1), ii) use of marginal quality groundwater from tubewell (T2), and iii) conjunctive use by mixing with the ratio of 1:1 of canal water and marginal quality tubewell water (T3). Water was applied to the crop cultivated in Kharif season 2011; its quantity has been measured using cut-throat flume. Total 11 watering each of 50 mm depth have been applied from 20th April to 20th July, 2011. Further, irrigations were stopped due to monsoon rainfall up to crop harvesting. Maximum crop yield (seed cotton) was observed under T1 which was 1,517 kg/ha followed by T3 (mixed canal and tubewell water) having 1009 kg/ha and T2 i.e. marginal quality groundwater having 709 kg/ha. This concludes that crop yield in T2 and T3 in comparison to T1was reduced by about 53 and 30% respectively. It has been observed that yield of cotton crop is below potential limit for three treatments due to unexpected rainfall at the time of full flowering season; thus the yield was adversely affected. However, salt deposition in soil profiles was not observed that is due to leaching effect of heavy rainfall occurred during monsoon season.
Keywords: Conjunctive Use, Cotton Crop, Groundwater, Soil Salinity Status, Water Use Efficiency (WUE).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2366483 Thermo-Mechanical Characterization of MWCNTs-Modified Epoxy Resin
Authors: M. Dehghan, R. Al-Mahaidi, I. Sbarski
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An industrial epoxy adhesive used in Carbon Fiber Reinforced Polymer (CFRP) strengthening systems was modified by dispersing multi-walled carbon nanotubes (MWCNTs). Nanocomposites were fabricated using the solvent-assisted dispersion method and ultrasonic mixing. Thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests were conducted to study the effect of nanotubes dispersion on the thermal and mechanical properties of the epoxy composite. Experimental results showed a substantial enhancement in the decomposition temperature and tensile properties of epoxy composite, while, the glass transition temperature (Tg) was slightly reduced due to the solvent effect. The morphology of the epoxy nanocomposites was investigated by SEM. It was proved that using solvent improves the nanotubes dispersion. However, at contents higher than 2 wt. %, nanotubes started to re-bundle in the epoxy matrix which negatively affected the final properties of epoxy composite.
Keywords: Carbon Fiber Reinforced Polymer, Epoxy, Multi-Walled Carbon Nanotube, Glass Transition Temperature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3354482 Electric Field Impact on the Biomass Gasification and Combustion Dynamics
Authors: M. Zake, I. Barmina, A. Kolmickovs, R. Valdmanis
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Experimental investigations of the DC electric field effect on thermal decomposition of biomass, formation of the axial flow of volatiles (CO, H2, CxHy), mixing of volatiles with swirling airflow at low swirl intensity (S ≈ 0.2-0.35), their ignition and on formation of combustion dynamics are carried out with the aim to understand the mechanism of electric field influence on biomass gasification, combustion of volatiles and heat energy production. The DC electric field effect on combustion dynamics was studied by varying the positive bias voltage of the central electrode from 0.6 kV to 3 kV, whereas the ion current was limited to 2 mA. The results of experimental investigations confirm the field-enhanced biomass gasification with enhanced release of volatiles and the development of endothermic processes at the primary stage of thermochemical conversion of biomass determining the field-enhanced heat energy consumption with the correlating decrease of the flame temperature and heat energy production at this stage of flame formation. Further, the field-enhanced radial expansion of the flame reaction zone correlates with a more complete combustion of volatiles increasing the combustion efficiency by 3% and decreasing the mass fraction of CO, H2 and CxHy in the products, whereas by 10% increases the average volume fraction of CO2 and the heat energy production downstream the combustor increases by 5-10%
Keywords: Biomass, combustion, electrodynamic control, gasification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1609481 Improvements in Material Handling: A Case Study of Cement Manufacturing Plant
Authors: A. Pancharya
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The globalization of the Indian economy has thrown a great challenge to the Indian industries in respect of productivity, quality, cost, delivery etc. Achieving success• the global market has required fundamental shift in the way business is conducted and has dramatically affected virtually every aspect of process industry. The internal manufacturing process and supporting infrastructure should be such that it can compete successfully in global markets with better flexibility and delivery. The paper deals with a case study of a reputed process industry, some changes in the process has been suggested, which leads to reduction in labor cost and production cost.
Keywords: Indian cement industry, material handling, plant layout.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4894480 The Comprehensive Study Based on Ultrasonic and X-ray Visual Technology for GIS Equipment Detection
Authors: Wei Zhang, Hong Yu, Xian-ping Zhao, Da-da Wang, Fei Xue
Abstract:
For lack of the visualization of the ultrasonic detection method of partial discharge (PD), the ultrasonic detection technology combined with the X-ray visual detection method (UXV) is proposed. The method can conduct qualitative analysis accurately and conduct reliable positioning diagnosis to the internal insulation defects of GIS, and while it could make up the blindness of the X-ray visual detection method and improve the detection rate. In this paper, an experimental model of GIS is used as the trial platform, a variety of insulation defects are set inside the GIS cavity. With the proposed method, the ultrasonic method is used to conduct the preliminary detection, and then the X-ray visual detection is used to locate and diagnose precisely. Therefore, the proposed UXV technology is feasible and practical.Keywords: GIS, ultrasonic, visual detection, X-ray
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1721479 Evaluation on Bearing Capacity of Ring Foundations on two-Layered Soil
Authors: R. Ziaie Moayed, V. Rashidian, E. Izadi
Abstract:
This paper utilizes a finite element analysis to study the bearing capacity of ring footings on a two-layered soil. The upper layer, that the footing is placed on it, is soft clay and the underneath layer is a cohesionless sand. For modeling soils, Mohr–Coulomb plastic yield criterion is employed. The effects of two factors, the clay layer thickness and the ratio of internal radius of the ring footing to external radius of the ring, have been analyzed. It is found that the bearing capacity decreases as the value of ri / ro increases. Although, as the clay layer thickness increases the bearing capacity was alleviated gradually.Keywords: Bearing capacity, Ring footing, Two-layered soil
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4041