Search results for: metallurgical defects and mechanical properties.
1379 Effect of Welding Processes on Tensile Behavior of Aluminum Alloy Joints
Authors: Chaitanya Sharma, Vikas Upadhyay, A. Tripathi
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Friction stir welding and tungsten inert gas welding techniques were employed to weld armor grade aluminum alloy to investigate the effect of welding processes on tensile behavior of weld joints. Tensile tests, Vicker microhardness tests and optical microscopy were performed on developed weld joints and base metal. Welding process influenced tensile behavior and microstructure of weld joints. Friction stir welded joints showed tensile behavior better than tungsten inert gas weld joints.Keywords: Friction stir welding, microstructure, tensile properties and fracture locations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23511378 Crystalline Model Approach for Studying the Nuclear Properties of Light Nuclei
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A study of the structure of the nucleus with the analogy by solid-state physics has been developed. We have used binding energy to calculate R (a parameter that is proportional to the radius of the nucleus) for deuteron, alpha, and 8Be. The calculated parameter r calculated from solid state physics produces a probe for calculation the nuclear radii. 8Be has special attention as it is radioactive nucleus and the latest nucleus to be calculated from crystalline model approach. The distribution of nucleons inside the nucleus is taken to be tetrahedral for 16O. The model has failed to expect the radius of 9Be which is an impression about the modification should be done on the model at near future. A comparison between our calculations and those from literature has been made, and a good agreement has been obtained.
Keywords: The structure of the nucleus, binding energy, crystalline model approach, nuclear radii, tetrahedral for 16O.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5081377 Nano Composite of Clay and Modified Ketonic Resin as Fire Retardant Polyol for Polyurethane
Authors: D. Önen, N. Kızılcan, B. Yıldız, A. Akar
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In situ modified cyclohexanone-formaldehyde resins were prepared by addition of alendronic acid during resin preparation. Clay nanocomposites in ketonic resins were achieved by adding clay into the flask at the beginning of the resin preparation. The prepared resins were used for the synthesis of fire resistant polyurethanes foam. Both phosphorous containing modifier compound alendronic acid and nanoclay increases fire resistance of the cyclohexanone-formaldehyde resin thus polyurethane produced from these resins. The effect of the concentrations of alendronic acid and clay on the fire resistance and physical properties of polyurethanes was studied.
Keywords: Alendronic acid, clay, ketonic resin, polyurethane.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29521376 Transient Heat Conduction in Nonuniform Hollow Cylinders with Time Dependent Boundary Condition at One Surface
Authors: Sen Yung Lee, Chih Cheng Huang, Te Wen Tu
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A solution methodology without using integral transformation is proposed to develop analytical solutions for transient heat conduction in nonuniform hollow cylinders with time-dependent boundary condition at the outer surface. It is shown that if the thermal conductivity and the specific heat of the medium are in arbitrary polynomial function forms, the closed solutions of the system can be developed. The influence of physical properties on the temperature distribution of the system is studied. A numerical example is given to illustrate the efficiency and the accuracy of the solution methodology.Keywords: Analytical solution, nonuniform hollow cylinder, time-dependent boundary condition, transient heat conduction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28601375 Experimental and Numerical Investigation of the Dispersion of Microparticles Emitted by Machining Operation
Authors: F. Tafnout, E. Belut, B. Oesterlé, J.R. Fontaine
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As a part of the development of a numerical method of close capture exhausts systems for machining devices, a test rig recreating a situation similar to a grinding operation, but in a perfectly controlled environment, is used. The properties of the obtained spray of solid particles are initially characterized using particle tracking velocimetry (PTV), in order to obtain input and validation parameters for numerical simulations. The dispersion of a tracer gas (SF6) emitted simultaneously with the particle jet is then studied experimentally, as the dispersion of such a gas is representative of that of finer particles, whose aerodynamic response time is negligible. Finally, complete modeling of the test rig is achieved to allow comparison with experimental results and thus to progress towards validation of the models used to describe a twophase flow generated by machining operation.Keywords: Pollutants, capture, tracer gas, SF6, PTV, numericalmodeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15241374 Identifying Chaotic Architecture: Origins of Nonlinear Design Theory
Authors: Mohammadsadegh Zanganehfar
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Through the emergence of modern architecture, an aggressive desire for new design theories appeared through the works of architects and critics. The discourse of complexity and volumetric composition happened to be an important and controversial issue in the discipline of architecture which was discussed through a general point of view in Robert Venturi and Denise Scott Brown's book “Complexity and contradiction in architecture” in 1966, this paper attempts to identify chaos theory as a scientific model of complexity and its relation to architecture design theory by conducting a qualitative analysis and multidisciplinary critical approach through architecture and basic sciences resources. Accordingly, we identify chaotic architecture as the correlation between chaos theory and the discipline of architecture, and as an independent nonlinear design theory with specific characteristics and properties.
Keywords: Architecture complexity, chaos theory, fractals, nonlinear dynamic systems, nonlinear ontology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10971373 Normalized Cumulative Spectral Distribution in Music
Authors: Young-Hwan Song, Hyung-Jun Kwon, Myung-Jin Bae
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As the remedy used music becomes active and meditation effect through the music is verified, people take a growing interest about psychological balance or remedy given by music. From traditional studies, it is verified that the music of which spectral envelop varies approximately as 1/f (f is frequency) down to a frequency of low frequency bandwidth gives psychological balance. In this paper, we researched signal properties of music which gives psychological balance. In order to find this, we derived the property from voice. Music composed by voice shows large value in NCSD. We confirmed the degree of deference between music by curvature of normalized cumulative spectral distribution. In the music that gives psychological balance, the curvature shows high value, otherwise, the curvature shows low value.Keywords: Cognitive Psychology, Normalized Cumulative Spectral Distribution, Curvature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22081372 Mobile Ad Hoc Networks and It’s Routing Protocols
Authors: Rakesh Kumar, Piush Verma, Yaduvir Singh
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A mobile ad hoc network (MANET) is a self configuring network, without any centralized control. The topology of this network is not always defined. The main objective of this paper is to introduce the fundamental concepts of MANETs to the researchers and practitioners, who are involved in the work in the area of modeling and simulation of MANETs. This paper begins with an overview of mobile ad hoc networks. Then it proceeds with the overview of routing protocols used in the MANETS, their properties and simulation methods. A brief tabular comparison between the routing protocols is also given in this paper considering different routing protocol parameters. This paper introduces a new routing scheme developed by the use of evolutionary algorithms (EA) and analytical hierarchy process (AHP) which will be used for getting the optimized output of MANET. In this paper cryptographic technique, ceaser cipher is also employed for making the optimized route secure.
Keywords: AHP, AODV, Cryptography, EA, MANET, Optimized output.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 40241371 A Review on Application of Chitosan as a Natural Antimicrobial
Authors: F. Nejati Hafdani, N. Sadeghinia
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In recent years application of natural antimicrobials instead of conventional ones, due to their hazardous effects on health, has got serious attentions. On the basis of the results of different studies, chitosan, a natural bio-degradable and non-toxic biopolysaccharide derived from chitin, has potential to be used as a natural antimicrobial. Chitosan has exhibited high antimicrobial activity against a wide variety of pathogenic and spoilage microorganisms, including fungi, and Gram-positive and Gramnegative bacteria. The antimicrobial action is influenced by intrinsic factors such as the type of chitosan, the degree of chitosan polymerization and extrinsic factors such as the microbial organism, the environmental conditions and presence of the other components. The use of chitosan in food systems should be based on sufficient knowledge of the complex mechanisms of its antimicrobial mode of action. In this article we review a number of studies on the investigation of chitosan antimicrobial properties and application of them in culture and food mediums.Keywords: Antimicrobial, Chitosan, Preservative
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 68031370 Comparative Analysis of Measures to Secure Two-Way Evacuation Routes for Vulnerable People during Large Disasters in a Historic Area
Authors: Nobuo Mishima, Naomi Miyamoto, Yoko Taguchi
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Historic preservation areas are extremely vulnerable to disasters because they are home to many vulnerable people and contain many closely spaced wooden houses. However, the narrow streets in these regions have historic meaning, which means that they cannot be widened and can become blocked easily during large disasters. Here, we describe our efforts to establish a methodology for the planning of evacuation route sin such historic preservation areas. In particular, this study aims to clarify the effectiveness of measures intended to secure two-way evacuation routes for vulnerable people during large disasters in a historic area preserved under the Cultural Properties Protection Law, Japan.Keywords: Historic preservation, evacuation route analysis, vulnerable people, street blockade.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15891369 Fabrication and Analysis of Bulk SiCp Reinforced Aluminum Metal Matrix Composites using Friction Stir Process
Authors: M.Puviyarasan, C.Praveen
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In this study, Friction Stir Processing (FSP) a recent grain refinement technique was employed to disperse micron-sized (2 *m) SiCp particles into aluminum alloy AA6063. The feasibility to fabricate bulk composites through FSP was analyzed and experiments were conducted at different traverse speeds and wider volumes of the specimens. Micro structural observation were carried out by employing optical microscopy test of the cross sections in both parallel and perpendicular to the tool traverse direction. Mechanical property including micro hardness was evaluated in detail at various regions on the specimen. The composites had an excellent bonding with aluminum alloy substrate and a significant increase of 30% in the micro hardness value of metal matrix composite (MMC) as to that of the base metal has observed. The observations clearly indicate that SiC particles were uniformly distributed within the aluminum matrix.
Keywords: Friction Stir Processing, Metal matrix composite, Bulk composite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20501368 Examining the Change of Power Transmission Line in Urban Regeneration with Geographical Information System
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In this study, spatial differences of Power Transmission Line (PTL) and effects of the situation before and after the urban regeneration are studied by using Geographical Information System (GIS). In addition, a questionable and analyzable structure is acquired by developed system. In the study area many parcels on the PTL were analyzed. The amount of the parcels, which are affected by the negativity of PTL is clearly seen with the aid of generated maps. Some kind of changes are exhibited in the system, which are created by GIS, for instance before urban regeneration PTL was very close to people’s private properties and huge parts of PTL were among the buildings, however; after urban regeneration electricity lines were changed their locations to the underground. According to the results, GIS can be used as a device in planning and managing of PTL in urban regeneration projects and can be used for analyses. By the help of GIS technology, necessary investigations should be carried out in urban regeneration applications for creating sustainable cities.Keywords: GIS, power transmission line, urban regeneration, technology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12251367 Assessment of the Environmental Destructive Effects of Building Dams
Authors: Mohammad Reza Pirestani, Mehdi Shafaghati, Amir Ahmad Dehghani
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From the beginning of creation, human being has ever fought against the ecosystem by changes has made in environment. The most environmental changes on the nature have been done after starting the concentrated life in the same region. Dams are one of the most important buildings in water resources and transferring. These buildings have been made from old times without access to hydrological, hydraulically, hydro mechanical information. Dams have positive and negative effects on environment. Constructing a dam relatively causes equal ecological consequences. According to different criteria, environmental effects of dams can lead short term and long term damages. These effects may influence on the situation and treatment of meteorology, biology, culture, ancient works, etc and severely causes to change and complicate it. So considering importance of positive effects of dam construction, it is necessary to minimize negative environmental effects of dams to achieve a stable development. In this article the considered effects and their solutions in influencing on assessment of destructive environmental effects of dams construction have been surveyed and presented.Keywords: Dam, Environment, Water Resources, Assessment
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 36161366 A P-SPACE Algorithm for Groebner Bases Computation in Boolean Rings
Authors: Quoc-Nam Tran
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The theory of Groebner Bases, which has recently been honored with the ACM Paris Kanellakis Theory and Practice Award, has become a crucial building block to computer algebra, and is widely used in science, engineering, and computer science. It is wellknown that Groebner bases computation is EXP-SPACE in a general setting. In this paper, we give an algorithm to show that Groebner bases computation is P-SPACE in Boolean rings. We also show that with this discovery, the Groebner bases method can theoretically be as efficient as other methods for automated verification of hardware and software. Additionally, many useful and interesting properties of Groebner bases including the ability to efficiently convert the bases for different orders of variables making Groebner bases a promising method in automated verification.Keywords: Algorithm, Complexity, Groebner basis, Applications of Computer Science.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18391365 Photonic Crystals for Novel Applications in Integrated-Optic Communication Systems and Devices
Authors: Vijay Janyani, Neetu Joshi, Jigyasa Pagaria, Parul Pathak
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Photonic Crystal (PhC) based devices are being increasingly used in multifunctional, compact devices in integrated optical communication systems. They provide excellent controllability of light, yet maintaining the small size required for miniaturization. In this paper, the band gap properties of PhCs and their typical applications in optical waveguiding are considered. Novel PhC based applications such as nonlinear switching and tapers are considered and simulation results are shown using the accurate time-domain numerical method based on Finite Difference Time Domain (FDTD) scheme. The suitability of these devices for novel applications is discussed and evaluated.Keywords: Band gap engineering, Nonlinear switching, Photonic crystals, PhC tapers, waveguides.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14461364 Degradation of Endosulfan in Different Soils by Indigenous and Adapted Microorganisms
Authors: A. Özyer, N. G. Turan, Y. Ardalı
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The environmental fate of organic contaminants in soils is influenced significantly by the pH, texture of soil, water content and also presence of organic matter. In this study, biodegradation of endosulfan isomers was studied in two different soils (Soil A and Soil B) that have contrasting properties in terms of their texture, pH, organic content, etc. Two Nocardia sp., which were isolated from soil, were used for degradation of endosulfan. Soils were contaminated with commercial endosulfan. Six sets were maintained from two different soils, contaminated with different endosulfan concentrations for degradation experiments. Inoculated and uninoculated mineral media with Nocardia isolates were added to the soils and mixed. Soils were incubated at a certain temperature (30 °C) during ten weeks. Residue endosulfan and its metabolites’ concentrations were determined weekly during the incubation period. The changes of the soil microorganisms were investigated weekly.
Keywords: Endosulfan, biodegradation, Nocardia sp., soil, organochlorine pesticide.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14101363 Some Design Issues in Designing of 50KW 50Krpm Permanent Magnet Synchronous Machine
Authors: Ali A. Mehna, Mohmed A. Ali, Ali S. Zayed
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A numbers of important developments have led to an increasing attractiveness for very high speed electrical machines (either motor or generator). Specifically the increasing switching speed of power electronics, high energy magnets, high strength retaining materials, better high speed bearings and improvements in design analysis are the primary drivers in a move to higher speed. The design challenges come in the mechanical design both in terms of strength and resonant modes and in the electromagnetic design particularly in respect of iron losses and ac losses in the various conducting parts including the rotor. This paper describes detailed design work which has been done on a 50,000 rpm, 50kW permanent magnet( PM) synchronous machine. It describes work on electromagnetic and rotor eddy current losses using a variety of methods including both 2D finite element analysisKeywords: High speed, PM motor, rotor and stator losses, finiteelement analysis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26531362 A New Damage Identification Strategy for SHM Based On FBGs and Bayesian Model Updating Method
Authors: Yanhui Zhang, Wenyu Yang
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One of the difficulties of the vibration-based damage identification methods is the nonuniqueness of the results of damage identification. The different damage locations and severity may cause the identical response signal, which is even more severe for detection of the multiple damage. This paper proposes a new strategy for damage detection to avoid this nonuniqueness. This strategy firstly determines the approximates damage area based on the statistical pattern recognition method using the dynamic strain signal measured by the distributed fiber Bragg grating, and then accurately evaluates the damage information based on the Bayesian model updating method using the experimental modal data. The stochastic simulation method is then used to compute the high-dimensional integral in the Bayesian problem. Finally, an experiment of the plate structure, simulating one part of mechanical structure, is used to verify the effectiveness of this approach.
Keywords: Bayesian method, damage detection, fiber Bragg grating, structural health monitoring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19121361 Chaotic Response and Bifurcation Analysis of Gear-Bearing System with and without Porous Effect under Nonlinear Suspension
Authors: Cai-Wan Chang-Jian
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This study presents a systematic analysis of the dynamic behaviors of a gear-bearing system with porous squeeze film damper (PSFD) under nonlinear suspension, nonlinear oil-film force and nonlinear gear meshing force effect. It can be found that the system exhibits very rich forms of sub-harmonic and even the chaotic vibrations. The bifurcation diagrams also reveal that greater values of permeability may not only improve non-periodic motions effectively, but also suppress dynamic amplitudes of the system. Therefore, porous effect plays an important role to improve dynamic stability of gear-bearing systems or other mechanical systems. The results presented in this study provide some useful insights into the design and development of a gear-bearing system for rotating machinery that operates in highly rotational speed and highly nonlinear regimes.
Keywords: Gear, PSFD, bifurcation, chaos.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21411360 The Relationship between Fatigue Crack Growth and Residual Stress in Rails
Authors: F. Husem, M. E. Turan, Y. Sun, H. Ahlatci, I. Tozlu
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Residual stress and fatigue crack growth rates are important to determine mechanical behavior of rails. This study aims to make relationship between residual stress and fatigue crack growth values in rails. For this purpose, three R260 quality rails (0.6-0.8% C, 0.6-1.25 Mn) were chosen. Residual stress of samples was measured by cutting method that is related in railway standard. Then samples were machined for fatigue crack growth test and analyze was completed according to the ASTM E647 standard which gives information about parameters of rails for this test. Microstructure characterizations were examined by Light Optic Microscope (LOM). The results showed that residual stress change with fatigue crack growth rate. The sample has highest residual stress exhibits highest crack growth rate and pearlitic structure can be seen clearly for all samples by microstructure analyze.
Keywords: Residual stress, fatigue crack growth, R260, LOM, ASTM E647.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16551359 Preparation and Characterisation of Chemically Activated Almond Shells by Optimization of Adsorption Parameters for Removal of Chromium VI from Aqueous Solutions
Authors: Inamullah Bhatti, Khadija Qureshi, R. A. Kazi, Abdul Khalique Ansari
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Activated carbon was prepared from agricultural waste “almond (Prunus amygdalus) nut shells" by chemical activation with phosphoric acid as an activating agent at 450 °C for 24 hr soaking time. The physical and chemical properties were analyzed. The adsorption of chromium VI from aqueous solution on almond nut shell activated carbon (ASAC) was investigated. The adsorption process parameters pH, agitation speed, agitation time, adsorbent dose were optimized. 98% of Cr VI was sorbed at pH 2 and stirring speed 200 rpm.. Surface structure showed that ASAC has a spongy type structure showing large number of pores
Keywords: adsorption, sorbent , sorbate and activation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24591358 Construction of Green Aggregates from Waste Processing
Authors: Fahad K. Alqahtani
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Nowadays construction industry is developing means to incorporate waste products in concrete to ensure sustainability. To meet the need of construction industry, a synthetic aggregate was developed using optimized technique called compression moulding press technique. The manufactured aggregate comprises mixture of plastic, waste which acts as binder, together with by-product waste which acts as fillers. The physical properties and microstructures of the inert materials and the manufactured aggregate were examined and compared with the conventional available aggregates. The outcomes suggest that the developed aggregate has potential to be used as substitution of conventional aggregate due to its less weight and water absorption. The microstructure analysis confirmed the efficiency of the manufacturing process where the final product has the same mixture of binder and filler.
Keywords: Fly ash, plastic waste, quarry fine, red sand, synthetic aggregate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7201357 CFD Simulation of Dense Gas Extraction through Polymeric Membranes
Authors: Azam Marjani, Saeed Shirazian
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In this study is presented a general methodology to predict the performance of a continuous near-critical fluid extraction process to remove compounds from aqueous solutions using hollow fiber membrane contactors. A comprehensive 2D mathematical model was developed to study Porocritical extraction process. The system studied in this work is a membrane based extractor of ethanol and acetone from aqueous solutions using near-critical CO2. Predictions of extraction percentages obtained by simulations have been compared to the experimental values reported by Bothun et al. [5]. Simulations of extraction percentage of ethanol and acetone show an average difference of 9.3% and 6.5% with the experimental data, respectively. More accurate predictions of the extraction of acetone could be explained by a better estimation of the transport properties in the aqueous phase that controls the extraction of this solute.Keywords: Solvent extraction, Membrane, Mass transfer, Densegas, Modeling
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15991356 Effect of Bentonite on the Properties of Liquid Insulating Oil
Authors: Loai Nasrat, Mervat S. Hassan
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Bentonitic material from South Aswan, Egypt was evaluated in terms of mineral-ogy and chemical composition as bleaching clay in refining of transformer oil before and after acid activation and thermal treatment followed by acid leaching using HCl and H2SO4 for different contact times. Structural modification and refining power of bento-nite were investigated during modification by means of X-ray diffraction and infrared spectroscopy. The results revealed that the activated bentonite could be used for refining of transformer oil. The oil parameters such as; dielectric strength, viscosity and flash point had been improved. The dielectric breakdown strength of used oil increased from 29 kV for used oil treated with unactivated bentonite to 74 kV after treatment with activated bentonite. Kinematic Viscosity changed from 19 to 11 mm2 /s after treatment with activated bentonite. However, flash point achieved 149 ºC.
Keywords: Dielectric strength, unactivated bentonite, X-ray diffraction, SEM image
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26971355 Antibacterial Activity of the Chennopodium album Leaves and Flowers Extract
Authors: Leila Amjad, Zohreh Alizad
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Recent years have instance that there is a invigoration of interest in drug discovery from medicinal plants for the support of health in all parts of the world . This study was designed to examine the in vitro antimicrobial activities of the flowers and leaves methanolic and ethanolic extracts of Chenopodium album L. Chenopodium album Linn. flowers and leaves were collected from East Esfahan, Iran. The effects of methanolic and ethanolic extracts were tested against 4 bacterial strains by using disc,well-diffusion method. Results showed that flowers and leaves methanolic and ethanolic extracts of C.album don-t have any activity against the selected bacterial strains. Our study has indicated that ,there are effective different factors on antimicrobial properties of plant extractsKeywords: Chennopodium album, antibacterial activity, extract
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32151354 Effect of Salt Solution and Plasticity Index on undrain Shear Strength of Clays
Authors: S .A. Naeini, M. A. Jahanfar
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Compacted clay liners (CCLs) are the main materials used in waste disposal landfills due to their low permeability. In this study, the effect on the shear resistant of clays with inorganic salt solutions as permeate fluid was experimentally investigated. For this purpose, NaCl inorganic salt solution at concentrations of 2, 5, 10% and deionized water were used. Laboratory direct shear and Vane shear tests were conducted on three compacted clays with low, medium and high plasticity. Results indicated that the solutions type and its concentration affect the shear properties of the mixture. In the light of this study, the influence magnitude of these inorganic salts in varies concentrations in different clays were determined and more suitable compacted clay with the compare of plasticity were found.Keywords: landfill liner, shear resistant, plasticity, salt solution
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 39221353 Hybrid Minimal Repair for a Serial System
Authors: Ellysa Nursanti, Anas Ma'ruf, Tota Simatupang, Bermawi P. Iskandar
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This study proposes a hybrid minimal repair policy which combines periodic maintenance policy with age-based maintenance policy for a serial production system. Parameters of such policy are defined as and which indicate as hybrid minimal repair time and planned preventive maintenance time respectively . Under this hybrid policy, the system is repaired minimally if it fails during ,. A perfect repair is conducted on the first failure after at any machines. At the same time, we take opportunity to advance the preventive maintenance of other machines simultaneously. If the system is still operating properly up to , then the preventive maintenance is carried out as its predetermined schedule. For a given , we obtain the optimal value which minimizes the expected cost per time unit. Numerical example is presented to illustrate the properties of the optimal solution.Keywords: Hybrid minimal repair, opportunistic maintenance, preventive maintenance, series system
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16641352 Practice of Social Audit in Hotel Companies: Case Study of Agadir, Morocco
Authors: M. El Mousadik, F. Elkandoussi
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The concern for increased rigor in social management has led more and more Moroccan business leaders to question the value of applying social audit as an essential tool in the management of human resources. Hotel companies are not excluded; in fact, they are expected to implement such an audit to develop sound and credible human resources management (HRM) policies. The main objective of this paper is to establish the relationship between the practice of social audit as a tool, and its impact on the tourism sector, especially on hotels at one of the Morocco’s first and most popular city for tourism, Agadir. This exploratory study of properties in Agadir has revealed that hotel executives are aware of the importance of social auditing to hone their decisions in the field of HRM.
Keywords: Social audit, hotel companies, human resources management, social piloting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18271351 Hydrogen Sensor Based on Surface Activated WO3 Films by Pd Nanoclusters
Authors: S.Fardindoost, A. Iraji Zad, S.M.Mahdavi
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Tungsten trioxide has been prepared by using P-PTA as a precursor on alumina substrates by spin coating method. Palladium introduced on WO3 film via electrolysis deposition by using palladium chloride as catalytic precursor. The catalytic precursor was introduced on the series of films with different morphologies. X-ray diffractometry (XRD), Scanning electron microscopy (SEM) and XPS were applied to analyze structure and morphology of the fabricated thin films. Then we measured variation of samples- electrical conductivity of pure and Pd added films in air and diluted hydrogen. Addition of Pd resulted in a remarkable improvement of the hydrogen sensing properties of WO3 by detection of Hydrogen below 1% at room temperature. Also variation of the electrical conductivity in the presence of diluted hydrogen revealed that response of samples depends rather strongly on the palladium configuration on the surface.Keywords: Electrolysis, Hydrogen sensing, Palladium, WO3
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21941350 A Visual Cryptography and Statistics Based Method for Ownership Identification of Digital Images
Authors: Ching-Sheng Hsu, Young-Chang Hou
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In this paper, a novel copyright protection scheme for digital images based on Visual Cryptography and Statistics is proposed. In our scheme, the theories and properties of sampling distribution of means and visual cryptography are employed to achieve the requirements of robustness and security. Our method does not need to alter the original image and can identify the ownership without resorting to the original image. Besides, our method allows multiple watermarks to be registered for a single host image without causing any damage to other hidden watermarks. Moreover, it is also possible for our scheme to cast a larger watermark into a smaller host image. Finally, experimental results will show the robustness of our scheme against several common attacks.
Keywords: Copyright protection, digital watermarking, samplingdistribution, visual cryptography.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1886