Search results for: structural characteristics
2386 Investigation about Structural and Optical Properties of Bulk and Thin Film of 1H-CaAlSi by Density Functional Method
Authors: M. Babaeipour, M. Vejdanihemmat
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Optical properties of bulk and thin film of 1H-CaAlSi for two directions (1,0,0) and (0,0,1) were studied. The calculations are carried out by Density Functional Theory (DFT) method using full potential. GGA approximation was used to calculate exchange-correlation energy. The calculations are performed by WIEN2k package. The results showed that the absorption edge is shifted backward 0.82eV in the thin film than the bulk for both directions. The static values of the real part of dielectric function for four cases were obtained. The static values of the refractive index for four cases are calculated too. The reflectivity graphs have shown an intensive difference between the reflectivity of the thin film and the bulk in the ultraviolet region.
Keywords: 1H-CaAlSi, absorption, bulk, optical, thin film.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9182385 Comparison of Two-Phase Critical Flow Models for Estimation of Leak Flow Rate through Cracks
Authors: Tadashi Watanabe, Jinya Katsuyama, Akihiro Mano
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The estimation of leak flow rates through narrow cracks in structures is of importance for nuclear reactor safety, since the leak flow could be detected before occurrence of loss-of-coolant accidents. The two-phase critical leak flow rates are calculated using the system analysis code, and two representative non-homogeneous critical flow models, Henry-Fauske model and Ransom-Trapp model, are compared. The pressure decrease and vapor generation in the crack, and the leak flow rates are found to be larger for the Henry-Fauske model. It is shown that the leak flow rates are not affected by the structural temperature, but affected largely by the roughness of crack surface.
Keywords: Crack, critical flow, leak, roughness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8532384 Earthquake Analysis of Reinforce Concrete Framed Structures with Added Viscous Dampers
Authors: F. Hejazi, J. Noorzaei, M. S. Jaafar, A. A. Abang Abdullah
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This paper describes the development of a numerical finite element algorithm used for the analysis of reinforced concrete structure equipped with shakes energy absorbing device subjected to earthquake excitation. For this purpose a finite element program code for analysis of reinforced concrete frame buildings is developed. The performance of developed program code is evaluated by analyzing of a reinforced concrete frame buildings model. The results are show that using damper device as seismic energy dissipation system effectively can reduce the structural response of framed structure during earthquake occurrence.
Keywords: Viscous Damper, finite element, program coding
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19082383 Numerical Study on the Response of Reinforced Concrete Wall Resisting the Impact Loading
Authors: DucKien Thai, Seung EockKim
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A numerical analysis of a reinforced concrete (RC) wall under missile impact loading is presented in this study. The model created by Technical Research Center of Finland was used. The commercial finite element code, LS-DYNA was used to analyze. The structural components of the reinforced concrete wall, missile and their contacts are fully modeled. The material nonlinearity with strain rate effects considering damage and failure is included in the analysis. The results of analysis were verified with other research results. The case-studies with different reinforcement ratios were conducted to investigate the influence of reinforcement on the punching behavior of walls under missile impact.
Keywords: Missile Impact, Reinforced Concrete Walls, LSDYNA, Dynamic Analysis, Punching Behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25642382 Utilising Unground Oil Palm Ash in Producing Foamed Concrete and Its Implementation as an Interlocking Mortar-Less Block
Authors: Hanizam Awang, Mohammed Zuhear Al-Mulali
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In this study, the possibility of using unground oil palm ash (UOPA) for producing foamed concrete is investigated. The UOPA used in this study is produced by incinerating palm oil biomass at a temperature exceeding 1000ºC. A semi-structural density of 1300kg/m3 was used with filler to binder ratio of 1.5 and preliminary water to binder ratio of 0.45. Cement was replaced by UOPA at replacement levels of 0, 25, 35, 45, 55 and 65% by weight of binder. Properties such as density, compressive strength, drying shrinkage and water absorption were investigated to the age of 90 days. The mix with a 35% of UOPA content was chosen to be used as the base material of a newly designed interlocking, mortar-less block system.
Keywords: Foamed concrete, oil palm ash, strength, interlocking block.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13662381 A Method for Measurement and Evaluation of Drape of Textiles
Authors: L. Fridrichova, R. Knížek, V. Bajzík
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Drape is one of the important visual characteristics of the fabric. This paper is introducing an innovative method of measurement and evaluation of the drape shape of the fabric. The measuring principle is based on the possibility of multiple vertical strain of the fabric. This method more accurately simulates the real behavior of the fabric in the process of draping. The method is fully automated, so the sample can be measured by using any number of cycles in any time horizon. Using the present method of measurement, we are able to describe the viscoelastic behavior of the fabric.
Keywords: Drape, drape shape, automated drape meter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8842380 A Programmable FSK-Modulator in 350nm CMOS Technology
Authors: Nasir Mehmood, Saad Rahman, Vinodh Ravinath, Mahesh Balaji
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This paper describes the design of a programmable FSK-modulator based on VCO and its implementation in 0.35m CMOS process. The circuit is used to transmit digital data at 100Kbps rate in the frequency range of 400-600MHz. The design and operation of the modulator is discussed briefly. Further the characteristics of PLL, frequency synthesizer, VCO and the whole design are elaborated. The variation among the proposed and tested specifications is presented. Finally, the layout of sub-modules, pin configurations, final chip and test results are presented.Keywords: FSK Modulator, CMOS, VCO, Phase Locked Loop, Frequency Synthesizer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17372379 Designing the Concrete-Framework Building and Examining its Behavior under the Explosion Load
Authors: Mehran Pourgholi , Amin Lotfi Eghlim
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These Nowadays the explosion of bombs or explosive materials such as gas and oil near or inside the buildings cause some losses in installations and building components. This has made the engineers to make the buildings and their components resistance against the effects of explosion. These activities lead to provide regulations and different methods. The above regulations are mostly focused on the explosion effects resulting from the vehicles around the buildings. Therefore, the explosion resulting from the vehicles outside the buildings will be studied in this research. In the present study, the main goals are to investigate the explosion load effects on the structures located on the piles with the specific quantity of plasticity and observing the permissible response of these structures. The concentrated mass system and the spring with two degree of freedom will be used to study the structural system.Keywords: Concrete-Framework Building, Explosion Load, piles.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12612378 Application of Four-electrode Method to Analysis Resistance Characteristics of Conductive Concrete
Authors: Chun-Yao Lee, Siang-Ren Wang
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The purpose of this paper is to discuss the influence of resistance characteristic on the high conductive concrete considering the various voltage and environment. The four-electrode method is applied to the tailor-made high conductive concrete with appropriate proportion. The curve of resistivity with the changes of voltage and environment is plotted and the changes of resistivity are explored. The result based on the methods reveals that resistivity is less affected by the temperature factor, and the four-electrode method would be an applicable measurement method on a site inspection.Keywords: Conductive concrete, Resistivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16082377 Investigation of Effective Parameters on Annealing and Hot Spotting Processes for Straightening of Bent Turbine Rotors
Authors: Esmaeil Poursaeidi, Mostafa Kamalzadeh Yazdi, Mohammadreza Mohammadi Arhani1
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The most severe damage of the turbine rotor is its distortion. The rotor straightening process must lead, at the first stage, to removal of the stresses from the material by annealing and next, to straightening of the plastic distortion without leaving any stress by hot spotting. The straightening method does not produce stress accumulations and the heating technique, developed specifically for solid forged rotors and disks, enables to avoid local overheating and structural changes in the material. This process also does not leave stresses in the shaft material. An experimental study of hot spotting is carried out on a large turbine rotor and some of the most important effective parameters that must be considered on annealing and hot spotting processes are investigated in this paper.Keywords: Annealing, Hot Spotting, Effective Parameter, Rotor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19872376 Coupling Concept of two Parallel Research Codes for Two and Three Dimensional Fluid Structure Interaction Analysis
Authors: Luciano Garelli, Marco Schauer, Jorge D’Elia, Mario A. Storti, Sabine C. Langer
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This paper discuss a coupling strategy of two different software packages to provide fluid structure interaction (FSI) analysis. The basic idea is to combine the advantages of the two codes to create a powerful FSI solver for two and three dimensional analysis. The fluid part is computed by a program called PETSc-FEM a software developed at Centro de Investigaci´on de M´etodos Computacionales –CIMEC. The structural part of the coupled process is computed by the research code elementary Parallel Solver – (ELPASO) of the Technische Universit¨at Braunschweig, Institut f¨ur Konstruktionstechnik (IK).
Keywords: Computational Fluid Dynamics (CFD), Fluid Structure Interaction (FSI), Finite Element Method (FEM).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19482375 Analysis of Direct Current Motor in LabVIEW
Authors: E. Ramprasath, P. Manojkumar, P. Veena
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DC motors have been widely used in the past centuries which are proudly known as the workhorse of industrial systems until the invention of the AC induction motors which makes a huge revolution in industries. Since then, the use of DC machines has been decreased due to enormous factors such as reliability, robustness and complexity but it lost its fame due to the losses. In this paper a new methodology is proposed to construct a DC motor through the simulation in LabVIEW to get an idea about its real time performances, if a change in parameter might have bigger improvement in losses and reliability.Keywords: Direct Current motor, LabVIEW software, modelling and analysis, overall characteristics of Direct Current motor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30802374 Definition of Cognitive Infocommunications and an Architectural Implementation of Cognitive Infocommunications Systems
Authors: Peter Baranyi, Gyorgy Persa, Adam Csapo
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Cognitive Infocommunications (CogInfoCom) is a new research direction which has emerged as the synergic convergence of infocommunications and the cognitive sciences. In this paper, we provide the definition of CogInfoCom, and propose an architectural framework for the interaction-oriented design of CogInfoCom systems. We provide the outlines of an application example of the interaction-oriented architecture, and briefly discuss its main characteristics.Keywords: Cognitive infocommunications, CogInfoCom, Cognitive Infocommunication Channels, CogInfoCom channels
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17732373 A Generic e-Tutor for Graphical Problems
Authors: B.W. Field
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For a variety of safety and economic reasons, engineering undergraduates in Australia have experienced diminishing access to the real hardware that is typically the embodiment of their theoretical studies. This trend will delay the development of practical competence, decrease the ability to model and design, and suppress motivation. The author has attempted to address this concern by creating a software tool that contains both photographic images of real machinery, and sets of graphical modeling 'tools'. Academics from a range of disciplines can use the software to set tutorial tasks, and incorporate feedback comments for a range of student responses. An evaluation of the software demonstrated that students who had solved modeling problems with the aid of the electronic tutor performed significantly better in formal examinations with similar problems. The 2-D graphical diagnostic routines in the Tutor have the potential to be used in a wider range of problem-solving tasks.
Keywords: CAL, graphics, modeling, structural distillation, tutoring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14212372 Effect of Oil Contamination on the Liquefaction Behavior of Sandy
Authors: S. A. Naeini, M. M. Shojaedin
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Oil leakage from the pipelines and the tanks carrying them, or during oil extraction, could lead to the changes in the characteristics and properties of the soil. In this paper, conducting a series of experimental cyclic triaxial tests, the effects of oil contamination on the liquefaction potential of sandy soils is investigated. The studied specimens are prepared by mixing the Firoozkuh sand with crude oil in 4, 8 and 12 percent by soil dry weight. The results show that the oil contamination up to 8% causes an increase in the soil liquefaction resistance and then with increase in the contamination, the liquefaction resistance decreases.
Keywords: Cyclic triaxial test, Liquefaction resistance, Oil contamination, Sandy soil.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25242371 Acceptance of Mobile Learning: a Respecification and Validation of Information System Success
Authors: Chin-Cheh Yi, Pei-Wen Liao, Chin-Feng Huang, I-Hui Hwang
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With the proliferation of mobile computing technology, mobile learning (m-learning) will play a vital role in the rapidly growing electronic learning market. However, the acceptance of m-learning by individuals is critical to the successful implementation of m-learning systems. Thus, there is a need to research the factors that affect users- intention to use m-learning. Based on an updated information system (IS) success model, data collected from 350 respondents in Taiwan were tested against the research model using the structural equation modeling approach. The data collected by questionnaire were analyzed to check the validity of constructs. Then hypotheses describing the relationships between the identified constructs and users- satisfaction were formulated and tested.
Keywords: m-learning, information system success, users' satisfaction, perceived value.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20012370 The Determination of Rating Points of Objects with Qualitative Characteristics and their Usagein Decision Making Problems
Authors: O. Poleshchuk, E. Komarov
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The paper presents the method developed to assess rating points of objects with qualitative indexes. The novelty of the method lies in the fact that the authors use linguistic scales that allow to formalize the values of the indexes with the help of fuzzy sets. As a result it is possible to operate correctly with dissimilar indexes on the unified basis and to get stable final results. The obtained rating points are used in decision making based on fuzzy expert opinions.Keywords: complete orthogonal semantic space, qualitativecharacteristic, rating points.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12172369 Lifting Wavelet Transform and Singular Values Decomposition for Secure Image Watermarking
Authors: Siraa Ben Ftima, Mourad Talbi, Tahar Ezzedine
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In this paper, we present a technique of secure watermarking of grayscale and color images. This technique consists in applying the Singular Value Decomposition (SVD) in LWT (Lifting Wavelet Transform) domain in order to insert the watermark image (grayscale) in the host image (grayscale or color image). It also uses signature in the embedding and extraction steps. The technique is applied on a number of grayscale and color images. The performance of this technique is proved by the PSNR (Pick Signal to Noise Ratio), the MSE (Mean Square Error) and the SSIM (structural similarity) computations.Keywords: Color image, grayscale image, singular values decomposition, lifting wavelet transform, image watermarking, watermark, secure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10352368 Production of Biodiesel from Different Edible Oils
Authors: Amir Shafeeq, Ayyaz Muhammad, Noman Hassan, Rofice Dickson
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Different vegetable oil based biodiesel (FAMES) were prepared by alkaline transesterification using refined oils as well as waste frying oil (WFO). Methanol and sodium hydroxide are used as catalyst under similar reaction conditions. To ensure the quality of biodiesel produced, a series of different ASTM Standard tests were carried out. In this context, various testwere done including viscosity, carbon residue, specific gravity, corrosion test, flash point, cloud point and pour point. Results revealed that characteristics of biodiesel depend on the feedstock and it is far better than petroleum diesel.
Keywords: Biodiesel, Edible oils, Separation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21262367 All Proteins Have a Basic Molecular Formula
Authors: Homa Torabizadeh
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This study proposes a basic molecular formula for all proteins. A total of 10,739 proteins belonging to 9 different protein groups classified on the basis of their functions were selected randomly. They included enzymes, storage proteins, hormones, signalling proteins, structural proteins, transport proteins, immunoglobulins or antibodies, motor proteins and receptor proteins. After obtaining the protein molecular formula using the ProtParam tool, the H/C, N/C, O/C, and S/C ratios were determined for each randomly selected sample. In this case, H, N, O, and S coefficients were specified per carbon atom. Surprisingly, the results demonstrated that H, N, O, and S coefficients for all 10,739 proteins are similar and highly correlated. This study demonstrates that despite differences in the structure and function, all known proteins have a similar basic molecular formula CnH1.58 ± 0.015nN0.28 ± 0.005nO0.30 ± 0.007nS0.01 ± 0.002n. The total correlation between all coefficients was found to be 0.9999.Keywords: Protein molecular formula, Basic unit formula, Protparam tool.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 80932366 Automated Stereophotogrammetry Data Cleansing
Authors: Stuart Henry, Philip Morrow, John Winder, Bryan Scotney
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The stereophotogrammetry modality is gaining more widespread use in the clinical setting. Registration and visualization of this data, in conjunction with conventional 3D volumetric image modalities, provides virtual human data with textured soft tissue and internal anatomical and structural information. In this investigation computed tomography (CT) and stereophotogrammetry data is acquired from 4 anatomical phantoms and registered using the trimmed iterative closest point (TrICP) algorithm. This paper fully addresses the issue of imaging artifacts around the stereophotogrammetry surface edge using the registered CT data as a reference. Several iterative algorithms are implemented to automatically identify and remove stereophotogrammetry surface edge outliers, improving the overall visualization of the combined stereophotogrammetry and CT data. This paper shows that outliers at the surface edge of stereophotogrammetry data can be successfully removed automatically.
Keywords: Data cleansing, stereophotogrammetry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18482365 Satisfaction Evaluation on the Fundamental Public Services for a Large-Scale Indemnificatory Residential Community: A Case Study of Nanjing
Authors: Dezhi Li, Peng Cui, Bo Zhang, Tengyuan Chang
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In order to solve the housing problem for the low-income families, the construction of affordable housing is booming in China. However, due to various reasons, the service facilities and systems in the indemnificatory residential community meet many problems. This article established a Satisfaction Evaluation System of the Fundamental Public Services for Large-scale Indemnificatory Residential Community based on the national standards and local criteria and developed evaluation methods and processes. At last, in the case of Huagang project in Nanjing, the satisfaction of basic public service is calculated according to a survey of local residents.Keywords: Indemnificatory residential community, public services, satisfaction evaluation, structural equation modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16072364 Entropy Based Data Hiding for Document Images
Authors: Swetha Kurup, Sridhar G., Sridhar V.
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In this paper we present a novel technique for data hiding in binary document images. We use the concept of entropy in order to identify document specific least distortive areas throughout the binary document image. The document image is treated as any other image and the proposed method utilizes the standard document characteristics for the embedding process. Proposed method minimizes perceptual distortion due to embedding and allows watermark extraction without the requirement of any side information at the decoder end.Keywords: Entropy, Steganography, Watermarking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15372363 Structure of Covering-based Rough Sets
Authors: Shiping Wang, Peiyong Zhu, William Zhu
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Rough set theory is a very effective tool to deal with granularity and vagueness in information systems. Covering-based rough set theory is an extension of classical rough set theory. In this paper, firstly we present the characteristics of the reducible element and the minimal description covering-based rough sets through downsets. Then we establish lattices and topological spaces in coveringbased rough sets through down-sets and up-sets. In this way, one can investigate covering-based rough sets from algebraic and topological points of view.
Keywords: Covering, poset, down-set, lattice, topological space, topological base.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18642362 Designing an Irregular Tensegrity as a Monumental Object
Authors: Buntara Sthenly Gan
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A novel and versatile numerical technique to solve a self-stress equilibrium state is adopted herein as a form-finding procedure for an irregular tensegrity structure. The numerical form-finding scheme of a tensegrity structure uses only the connectivity matrix and prototype tension coefficient vector as the initial guess solution. Any information on the symmetrical geometry or other predefined initial structural conditions is not necessary to get the solution in the form-finding process. An eight-node initial condition example is presented to demonstrate the efficiency and robustness of the proposed method in the form-finding of an irregular tensegrity structure. Based on the conception from the form-finding of an eight-node irregular tensegrity structure, a monumental object is designed by considering the real world situation such as self-weight, wind and earthquake loadings.
Keywords: Tensegrity, Form-finding, Design, Irregular, Self-stress, Force density method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17092361 Synthesis and Characterization of Gallosilicate Sodalite Containing NO2- Ions
Authors: Ashok V. Borhade, Sanjay G. Wakchaure
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Pure phase gallosilicate nitrite sodalite has been synthesized in a single step by low temperature (373 oK) hydrothermal technique. The product obtained was characterized using a combination of techniques including X-ray powder diffraction, IR, Raman spectroscopy, SEM, MAS NMR spectroscopy as well as thermogravimetry. Sodalite with an ideal composition was obtained after synthesis at 3730K and seven days duration using alkaline medium. The structural features of the Na8[GaSiO4]6(NO2)2 sodalite were investigated by IR, MAS NMR spectroscopy of 29Si and 23Na nuclei and by Reitveld refinement of X-ray powder diffraction data. The crystal structure of this sodalite has been refined in the space group P 4 3n; with a cell parameter 8.98386Å, V= 726.9 Å, (Rwp= 0.077 and Rp=0.0537) and Si-O-Ga angle is found to be 132.920 . MAS NMR study confirms complete ordering of Si and Ga in the gallosilicate framework. The surface area of single entity with stoichiometry Na8[GaSiO4]6(NO2)2 was found to be 8.083 x10-15 cm2/g.
Keywords: Gallosilicate, hydrothermal, nitrite, Reitveldrefinement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16282360 Energy Models for Analyzing the Economic Wide Impact of the Environmental Policies
Authors: Majdi M. Alomari, Nafesah I. Alshdaifat, Mohammad S. Widyan
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Different countries have introduced different schemes and policies to counter global warming. The rationale behind the proposed policies and the potential barriers to successful implementation of the policies adopted by the countries were analyzed and estimated based on different models. It is argued that these models enhance the transparency and provide a better understanding to the policy makers. However, these models are underpinned with several structural and baseline assumptions. These assumptions, modeling features and future prediction of emission reductions and other implication such as cost and benefits of a transition to a low-carbon economy and its economy wide impacts were discussed. On the other hand, there are potential barriers in the form political, financial, and cultural and many others that pose a threat to the mitigation options.Keywords: Economic wide impact, energy models, environmental policy instruments, mitigating CO2 emission.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15622359 Structural Properties of Polar Liquids in Binary Mixture Using Microwave Technique
Authors: Shagufta Tabassum, V. P. Pawar
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The study of static dielectric properties in a binary mixture of 1,2 dichloroethane (DE) and n,n dimethylformamide (DMF) polar liquids has been carried out in the frequency range of 10 MHz to 30 GHz for 11 different concentration using time domain reflectometry technique at 10ºC temperature. The dielectric relaxation study of solute-solvent mixture at microwave frequencies gives information regarding the creation of monomers and multimers as well as interaction between the molecules of the binary mixture. The least squares fit method is used to determine the values of dielectric parameters such as static dielectric constant (ε0), dielectric constant at high frequency (ε∞) and relaxation time (τ).
Keywords: Excess parameters, relaxation time, static dielectric constant, time domain reflectometry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7352358 Enhanced Thermal Properties of Rigid PVC Foams Using Fly Ash
Authors: Nidal H. Abu-Zahra, Parisa Khoshnoud, Murtatha Jamel, Subhashini Gunashekar
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PVC foam-fly ash composites (PVC-FA) are characterized for their structural, morphological, mechanical and thermal properties. The tensile strength of the composites increased modestly with higher fly ash loading, while there was a significant increase in the elastic modulus for the same composites. On the other hand, a decrease in elongation at UTS was observed upon increasing fly ash content due to increased rigidity of the composites. Similarly, the flexural modulus increased as the fly ash loading increased, where the composites containing 25 phr fly ash showed the highest flexural strength. Thermal properties of PVC-fly ash composites were determined by Thermo Gravimetric Analysis (TGA). The microstructural properties were studied by Scanning Electron Microscopy (SEM). SEM results confirm that fly ash particles were mechanically interlocked in PVC matrix with good interfacial interaction with the matrix. Particle agglomeration and debonding was observed in samples containing higher amounts of fly ash.
Keywords: PVC Foam, Polyvinyl Chloride, Rigid PVC, Fly Ash Composites.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32462357 Fault-Tolerant Control Study and Classification: Case Study of a Hydraulic-Press Model Simulated in Real-Time
Authors: Jorge Rodriguez-Guerra, Carlos Calleja, Aron Pujana, Iker Elorza, Ana Maria Macarulla
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Society demands more reliable manufacturing processes capable of producing high quality products in shorter production cycles. New control algorithms have been studied to satisfy this paradigm, in which Fault-Tolerant Control (FTC) plays a significant role. It is suitable to detect, isolate and adapt a system when a harmful or faulty situation appears. In this paper, a general overview about FTC characteristics are exposed; highlighting the properties a system must ensure to be considered faultless. In addition, a research to identify which are the main FTC techniques and a classification based on their characteristics is presented in two main groups: Active Fault-Tolerant Controllers (AFTCs) and Passive Fault-Tolerant Controllers (PFTCs). AFTC encompasses the techniques capable of re-configuring the process control algorithm after the fault has been detected, while PFTC comprehends the algorithms robust enough to bypass the fault without further modifications. The mentioned re-configuration requires two stages, one focused on detection, isolation and identification of the fault source and the other one in charge of re-designing the control algorithm by two approaches: fault accommodation and control re-design. From the algorithms studied, one has been selected and applied to a case study based on an industrial hydraulic-press. The developed model has been embedded under a real-time validation platform, which allows testing the FTC algorithms and analyse how the system will respond when a fault arises in similar conditions as a machine will have on factory. One AFTC approach has been picked up as the methodology the system will follow in the fault recovery process. In a first instance, the fault will be detected, isolated and identified by means of a neural network. In a second instance, the control algorithm will be re-configured to overcome the fault and continue working without human interaction.Keywords: Fault-tolerant control, electro-hydraulic actuator, fault detection and isolation, control re-design, real-time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 849