Search results for: Effective properties
2574 Compressive Strength and Capillary Water Absorption of Concrete Containing Recycled Aggregate
Authors: Yeşim Tosun, Remzi Şahin
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This paper presents results of compressive strength, capillary water absorption, and density tests conducted on concrete containing recycled aggregate (RCA) which is obtained from structural waste generated by the construction industry in Turkey. In the experiments, 0%, 15%, 30%, 45% and 60% of the normal (natural) coarse aggregate was replaced by the recycled aggregate. Maximum aggregate particle sizes were selected as 16 mm, 22,4 mm and 31,5 mm; and 0,06%, 0,13% and 0,20% of air-entraining agent (AEA) were used in mixtures. Fly ash and superplasticizer were used as a mineral and chemical admixture, respectively. The same type (CEM I 42.5) and constant dosage of cement were used in the study. Water/cement ratio was kept constant as 0.53 for all mixture. It was concluded that capillary water absorption, compressive strength, and density of concrete decreased with increasing RCA ratio. Increasing in maximum aggregate particle size and amount of AEA also affect the properties of concrete significantly.Keywords: Capillary water absorption, compressive strength, density, recycled concrete aggregates.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28192573 Design, Implementation and Analysis of Composite Material Dampers for Turning Operations
Authors: Lorenzo Daghini, Andreas Archenti, Cornel Mihai Nicolescu
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This paper introduces a novel design for boring bar with enhanced damping capability. The principle followed in the design phase was to enhance the damping capability minimizing the loss in static stiffness through implementation of composite material interfaces. The newly designed tool has been compared to a conventional tool. The evaluation criteria were the dynamic characteristics, frequency and damping ratio, of the machining system, as well as the surface roughness of the machined workpieces. The use of composite material in the design of damped tool has been demonstrated effective. Furthermore, the autoregressive moving average (ARMA) models presented in this paper take into consideration the interaction between the elastic structure of the machine tool and the cutting process and can therefore be used to characterize the machining system in operational conditions.
Keywords: ARMA, cutting stability, damped tool, machining.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28822572 Influence of Ammonium Concentration on the Performance of an Inorganic Biofilter Treating Methane
Authors: Marc Veillette, Antonio Avalos Ramirez, Michèle Heitz
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Among the technologies available to reduce methane emitted from the pig industry, biofiltration seems to be an effective and inexpensive solution. In methane (CH4) biofiltration, nitrogen is an important macronutrient for the microorganisms growth. The objective of this research project was to study the effect of ammonium (NH4 +) on the performance, the biomass production and the nitrogen conversion of a biofilter treating methane. For NH4 + concentrations ranging from 0.05 to 0.5 gN-NH4 +/L, the CH4 removal efficiency and the dioxide carbon production rate decreased linearly from 68 to 11.8 % and from 7.1 to 0.5 g/(m3-h), respectively. The dry biomass content varied from 4.1 to 5.8 kg/(m3 filter bed). For the same range of concentrations, the ammonium conversion decreased while the specific nitrate production rate increased. The specific nitrate production rate presented negative values indicating denitrification in the biofilter.Keywords: Methane, biofiltration, pig, ammonium, nitrification, denitrification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16962571 Laboratory Investigations on Mechanical Properties of High Volume Fly Ash Concrete and Composite Sections
Authors: Aravindkumar B. Harwalkar, S. S. Awanti
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Use of fly ash as a supplementary cementing material in large volumes can bring both technological and economic benefits for concrete industry. In this investigation mix proportions for high volume fly ash concrete were determined at cement replacement levels of 50%, 55%, 60% and 65% with low calcium fly ash. Flexural and compressive strengths of different mixes were measured at ages of 7, 28 and 90 days. Flexural strength of composite section prepared from pavement quality and lean high volume fly ash concrete was determined at the age of 28 days. High volume fly ash concrete mixes exhibited higher rate of strength gain and age factors than corresponding reference concrete mixes. The optimum cement replacement level for pavement quality concrete was found to be 60%. The consideration of bond between pavement quality and lean of high volume fly ash concrete will be beneficial in design of rigid pavements.
Keywords: Keywords—Composite section, Compressive strength, Flexural strength, Fly ash.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19562570 Prediction of Soil Hydraulic Conductivity from Particle-Size Distribution
Authors: A.F. Salarashayeri, M. Siosemarde
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Hydraulic conductivity is one parameter important for predicting the movement of water and contaminants dissolved in the water through the soil. The hydraulic conductivity is measured on soil samples in the lab and sometimes tests carried out in the field. The hydraulic conductivity has been related to soil particle diameter by a number of investigators. In this study, 25 set of soil samples with sand texture. The results show approximately success in predicting hydraulic conductivity from particle diameters data. The following relationship obtained from multiple linear regressions on data (R2 = 0.52): Where d10, d50 and d60, are the soil particle diameter (mm) that 10%, 50% and 60% of all soil particles are finer (smaller) by weight and Ks, saturated hydraulic conductivity is expressed in m/day. The results of regression analysis showed that d10 play a more significant role with respect to Ks, saturated hydraulic conductivity (m/day), and has been named as the effective parameter in Ks calculation.Keywords: hydraulic conductivity, particle diameter, particle-size distribution and soil
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 90072569 Personality of Military Professionals (Commanders) and Their Way of Leading and Commanding Today and in Historical Context
Authors: Petra Hurbišová, Monika Davidová
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The article deals with the personality of military professionals (commanders) and their way of leading and commanding today and in historical context. The first part focuses on the leadership skills of Alexander the Great, who introduced strategic innovations and even from today's perspective; he excelled in efficient work with people. This paper focuses on the way which he achieved his goals. Further attention is paid to approaches to commander´s personality by other great generals. The paper is also focused on personality traits of military professionals necessary for successful management and leadership in today's variable and challenging environment. Finally, attention is paid to the effective and ineffective ways of behavior of commanders and determining what styles of leadership is appropriate for a given situation, whether in peacetime or on deployment.Keywords: Authority, commander, leader, leadership, military professional, personality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23202568 On the Differentiation of Strategic Spatial Planning Making Mechanisms in New Era: Between Melbourne and Tianjin
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Strategic spatial planning, which is taken as an effective and competitive way for the governors of the city to improve the development and management level of a city, has been blooming in recent years all over the world. In the context of globalization and informatization, strategic spatial planning must transfer its focus on three different levels: global, regional and urban. Internal and external changes in environmental conditions lead to new advances in strategic planning both theoretically and practically. However, such advances or changes respond differently to cities on account of different dynamic mechanisms. This article aims at two cities of Tianjin in China and Melbourne in Australia, through a comparative study on strategic planning, to explore the differentiation of mechanisms in urban planning making. By comparison and exploration, the purpose of this article is to exhibit two different planning worlds between western and Chinese in a new way nowadays.
Keywords: Differentiation, Tianjin China, Melbourne Australia, strategic planning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22612567 Design of the Roller Clamp Robotic Assembly System
Authors: S. S. Ngu, L. C. Kho, T. P. Tan, M. S. Osman
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This work deals with the design of the robotic assembly system for the roller clamps. The task is characterized by high speed, high yield and safety engagement. This paper describes the design of different parts of an automated high speed machine to assemble the parts of roller clamps. The roller clamp robotic assembly system performs various processes in the assembly line which include clamp body and roller feeding, inserting the roller into the clamp body, and dividing the rejected clamp and successfully assembled clamp into their own tray. The electrical/electronics design of the machine is discussed. The target is to design a cost effective, minimum maintenance and high speed machine for the industry applications.Keywords: Machine design, assembly machine, roller clamp, industry applications.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21672566 Effect of Silver Nanoparticles Size Prepared by Photoreduction Method on Optical Absorption Spectra of TiO2/Ag/N719 Dye Composite Films
Authors: C. Photiphitak, P. Rakkwamsuk, P. Muthitamongkol, C. Sae-Kung, C. Thanachayanont
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TiO2/Ag composite films were prepared by incorporating Ag in the pores of mesoporous TiO2 films using a photoreduction method. The Ag nanoparticle sizes were in a range of 3.66-38.56 nm. The TiO2/Ag composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscropy (TEM). The TiO2 films and TiO2/Ag composite films were immersed in a 0.3 mM N719 dye solution and characterized by UV-Vis spectrophotometer. The TiO2/Ag/N719 composite film showed that an optimal size of Ag nanoparticles was 19.12 nm and, hence, gave the maximum optical absorption spectra. The improved absorption was due to surface plasmon resonance induced by the Ag nanoparticles to enhance the absorption coefficient of the dye.Keywords: Silver nanoparticle, TiO2/Ag composite films, Optical properties, surface plasmon resonance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26032565 Carbon Nanofibers Reinforced P(VdF-HFP) Based Gel Polymer Electrolyte for Lithium-Ion Battery Application
Authors: Anjan Sil, Rajni Sharma, Subrata Ray
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The effect of carbon nanofibers (CNFs) on the electrical properties of Poly(vinylidene fluoride-hexafluoropropylene) (P(VdF-HFP)) based gel polymer electrolytes has been investigated in the present work. The length and diameter ranges of CNFs used in the present work are 5-50 μm and 200-600 nm respectively. The nanocomposite gel polymer electrolytes have been synthesized by solution casting technique with varying CNFs content in terms of weight percentage. Electrochemical impedance analysis demonstrates that the reinforcement of carbon nanofibers significantly enhances the ionic conductivity of the polymer electrolyte. The decrease of crystallinity of P(VdF-HFP) due the addition of CNFs has been confirmed by X-ray diffraction (XRD). The interaction of CNFs with various constituents of nanocomposite gel polymer electrolytes has been assessed by Fourier Transform Infrared (FTIR) spectroscopy. Moreover CNFs added gel polymer electrolytes offer superior thermal stability as compared to that of CNFs free electrolytes as confirmed by Thermogravimetric analysis (TGA).Keywords: Polymer electrolytes, CNFs, Ionic conductivity, TGA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19432564 Design and Optimization of Coplanar Waveguide-Fed Sensing Antennas for ISM Band Applications
Authors: Vivek Bharti, Inderpreet Kaur, Saurabh Verma, Renu Gangwar, Hari Kumar Singh
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This work presents a dual-band Coplanar Waveguide (CPW) fed rectangular patch antenna designed for applications in Industrial, Scientific, and Medical (ISM) Band sensing. Fabricated on a cost-effective FR-4 substrate with specific dimensions, the antenna incorporates a rectangular slot and a copper patch, optimized through simulation to achieve desired characteristics, particularly focusing on the reflection coefficient. A unique feature is introduced through the integration of copper cells forming a Partially Reflecting Surface (PRS) to feed the antenna. Dual-band functionality is achieved, covering frequencies of 1.28 GHz-1.3 GHz and 4.9 GHz-5.2 GHz, catering to diverse communication needs within these frequency ranges. The addition of a superstrate enhances the antenna’s gain, resulting in 4.5 dBi at 1.28 GHz-1.3 GHz and 6.5 dBi at 4.9 GHz-5.2 GHz, with an efficiency of 58%.
Keywords: ISM, Coplanar waveguide fed, superstrate, circularly polarized.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1352563 Dynamic Active Earth Pressure on Flexible Cantilever Retaining Wall
Authors: Snehal R. Pathak, Sachin S. Munnoli
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Evaluation of dynamic earth pressure on retaining wall is a topic of primary importance. In present paper, dynamic active earth pressure and displacement of flexible cantilever retaining wall has been evaluated analytically using 2-DOF mass-spring-dashpot model by incorporating both wall and backfill properties. The effect of wall flexibility on dynamic active earth pressure and wall displacement are studied and presented in graphical form. The obtained results are then compared with the various conventional methods, experimental analysis and also with PLAXIS analysis. It is observed that the dynamic active earth pressure decreases with increase in the wall flexibility while wall displacement increases linearly with flexibility of the wall. The results obtained by proposed 2-DOF analytical model are found to be more realistic and economical.Keywords: Earth pressure, earthquake, 2-DOF model, plaxis, wall movement, retaining walls.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15172562 Comparison of Different PWM Switching Modes of BLDC Motor as Drive Train of Electric Vehicles
Authors: A. Tashakori, M. Ektesabi
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Electric vehicle (EV) is one of the effective solutions to control emission of greenhouses gases in the world. It is of interest for future transportation due to its sustainability and efficiency by automotive manufacturers. Various electrical motors have been used for propulsion system of electric vehicles in last decades. In this paper brushed DC motor, Induction motor (IM), switched reluctance motor (SRM) and brushless DC motor (BLDC) are simulated and compared. BLDC motor is recommended for high performance electric vehicles. PWM switching technique is implemented for speed control of BLDC motor. Behavior of different modes of PWM speed controller of BLDC motor are simulated in MATLAB/SIMULINK. BLDC motor characteristics are compared and discussed for various PWM switching modes under normal and inverter fault conditions. Comparisons and discussions are verified through simulation results.Keywords: BLDC motor, PWM switching technique, in-wheel technology, electric vehicle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 48452561 Impact Behavior of Cryogenically Treated En 52 and 21-4N Valve Steels
Authors: M. Arockia Jaswin, D. Mohan Lal
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Cryogenic treatment is the process of cooling a material to extremely low temperatures to generate enhanced mechanical and physical properties. The purpose of this study is to examine the effect of cryogenic treatment on the impact behavior of En 52 and 21-4N valve steels. The valve steels are subjected to shallow (193 K) and deep cryogenic treatment (85 K), and the impact behavior is compared with the valve steel materials subjected to conventional heat treatment. The impact test is carried out in accordance with the ASTM E 23-02a standard. The results show an improvement of 23 % in the impact energy for the En 52 deep cryo-treated samples when compared to that of the conventionally heat treated samples. It is revealed that during cryogenic treatment fine platelets of martensite are formed from the retained austenite, and these platelets promote the precipitation of fine carbides by a diffusion mechanism during tempering.
Keywords: Cryogenic treatment, valve steel, Fractograph, carbides, impact strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 45182560 Influence of Silica Fume on Ultrahigh Performance Concrete
Authors: Vitoldas Vaitkevičius, Evaldas Šerelis
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Silica fume, also known as microsilica (MS) or condensed silica fume is a by-product of the production of silicon metal or ferrosilicon alloys. Silica fume is one of the most effective pozzolanic additives which could be used for ultrahigh performance and other types of concrete. Despite the fact, however is not entirely clear, which amount of silica fume is most optimal for UHPC. Main objective of this experiment was to find optimal amount of silica fume for UHPC with and without thermal treatment, when different amount of quartz powder is substituted by silica fume. In this work were investigated four different composition of UHPC with different amount of silica fume. Silica fume were added 0, 10, 15 and 20% of cement (by weight) to UHPC mixture. Optimal amount of silica fume was determined by slump, viscosity, qualitative and quantitative XRD analysis and compression strength tests methods.
Keywords: Compressive strength, silica fume, ultrahigh performance concrete, XRD.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46072559 Carbon Accumulation in Winter Wheat under Different Growing Intensity and Climate Change
Authors: V. Povilaitis, S. Lazauskas, Š. Antanaitis, S. Sakalauskien, J. Sakalauskait, G. Pšibišauskien, O. Auškalnien, S. Raudonius, P. Duchovskis
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World population growth drives food demand, promotes intensification of agriculture, development of new production technologies and varieties more suitable for regional nature conditions. Climate change can affect the length of growing period, biomass and carbon accumulation in winter wheat. The increasing mean air temperature resulting from climate change can reduce the length of growth period of cereals, and without adequate adjustments in growing technologies or varieties, can reduce biomass and carbon accumulation. Deeper understanding and effective measures for monitoring and management of cereal growth process are needed for adaptation to changing climate and technological conditions.
Keywords: carbon, climate change, modeling, winter wheat
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18782558 Effect of Alginate and Surfactant on Physical Properties of Oil Entrapped Alginate Bead Formulation of Curcumin
Authors: Arpa Petchsomrit, Namfa Sermkaew, Ruedeekorn Wiwattanapatapee
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Oil entrapped floating alginate beads of curcumin were developed and characterized. Cremophor EL, Cremophor RH and Tween 80 were utilized to improve the solubility of the drug. The oil-loaded floating gel beads prepared by emulsion gelation method contained sodium alginate, mineral oil and surfactant. The drug content and % encapsulation declined as the ratio of surfactant was increased. The release of curcumin from 1% alginate beads was significantly more than for the 2% alginate beads. The drug released from the beads containing 25% of Tween 80 was about 70% while a higher drug release was observed with the beads containing Cremophor EL or Cremohor RH (approximately 90%). The developed floating beads of curcumin powder with surfactant provided a superior drug release than those without surfactant. Floating beads based on oil entrapment containing the drug solubilized in surfactants is a new delivery system to enhance the dissolution of poorly soluble drugs.
Keywords: Alginate, curcumin, floating drug delivery, oil entrapped bead.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 46372557 The Effect of Dispersed MWCNTs Using SDBS Surfactant on Bacterial Growth
Authors: J.E. Park, G.R. Kim, D.J. Yoon, C.H. Sin, I.S. Park, T.S. Bea, M.H. Lee
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Carbon nanotubes (CNTs) are attractive because of their excellent chemical durability mechanical strength and electrical properties. Therefore there is interest in CNTs for not only electrical and mechanical application, but also biological and medical application. In this study, the dispersion power of surfactant-treated multiwalled carbon nanotubes (MWCNTs) and their effect on the antibacterial activity were examined. Surfactant was used sodium dodecyl-benzenesulfonate (SDBS). UV-vis absorbance and transmission electron microscopy(TEM) were used to characterize the dispersion of MWCNTs in the aqueous phase, showing that the surfactant molecules had been adsorbed onto the MWCNTs surface. The surfactant-treated MWCNTs exhibited antimicrobial activities to streptococcus mutans. The optical density growth curves and viable cell number determined by the plating method suggested that the antimicrobial activity of surfactant-treated MWCNTs was both concentration and treatment time-dependent.Keywords: MWCNT, SDBS, surfactant, antibacterial.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30392556 Performance of Chaotic Lu System in CDMA Satellites Communications Systems
Authors: K. Kemih, M. Benslama
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This paper investigates the problem of spreading sequence and receiver code synchronization techniques for satellite based CDMA communications systems. The performance of CDMA system depends on the autocorrelation and cross-correlation properties of the used spreading sequences. In this paper we propose the uses of chaotic Lu system to generate binary sequences for spreading codes in a direct sequence spread CDMA system. To minimize multiple access interference (MAI) we propose the use of genetic algorithm for optimum selection of chaotic spreading sequences. To solve the problem of transmitter-receiver synchronization, we use the passivity controls. The concept of semipassivity is defined to find simple conditions which ensure boundedness of the solutions of coupled Lu systems. Numerical results are presented to show the effectiveness of the proposed approach.Keywords: About Chaotic Lu system, synchronization, Spreading sequence, Genetic Algorithm. Passive System
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17472555 Feasibility of Ground Alkali-Active Sandstone Powder for Use in Concrete as Mineral Admixture
Authors: Xia Chen, Hua-Quan Yang, Shi-Hua Zhou
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Alkali-active sandstone aggregate was ground by vertical and ball mill into particles with residue over 45 μm less than 12%, and investigations have been launched on particles distribution and characterization of ground sandstone powder, fluidity, heat of hydration, strength as well as hydration products morphology of pastes with incorporation of ground sandstone powder. Results indicated that ground alkali-active sandstone powder with residue over 45 μm less than 8% was easily obtainable, and specific surface area was more sensitive to characterize its fineness with extension of grinding length. Incorporation of sandstone powder resulted in higher water demand and lower strength, advanced hydration of C3A and C2S within 3days and refined pore structure. Based on its manufacturing, characteristics and influence on properties of pastes, it was concluded that sandstone powder was a good selection for use in concrete as mineral admixture.Keywords: Concrete, mineral admixture, hydration, structure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7162554 Computer-aided Sequence Planning of Shearing Operations in Progressive Dies
Authors: Alan C. Lin, Dean K. Sheu
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This paper aims to study the methodology of building the knowledge of planning adequate punches in order to complete the task of strip layout for shearing processes, using progressive dies. The proposed methodology uses die design rules and characteristics of different types of punches to classify them into five groups: prior use (the punches must be used first), posterior use (must be used last), compatible use (may be used together), sequential use (certain punches must precede some others) and simultaneous use (must be used together). With these five groups of punches, the searching space of feasible designs will be greatly reduced, and superimposition becomes a more effective method of punch layout. The superimposition scheme will generate many feasible solutions, an evaluation function based on number of stages, moment balancing and strip stability is developed for helping designers to find better solutions.
Keywords: Manufacturing systems, advances in metal forming, computer-aided design, progressive die.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21862553 A Study of Gas Metal Arc Welding Affecting Mechanical Properties of Austenitic Stainless Steel AISI 304
Authors: Sittichai K., Santirat N., Sompong., P
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The objective of this research was to study influence parameters affecting to mechanical property of austenitic stainless steel grade 304 (AISI 304) with Gas Metal Arc Welding (GMAW). The research was applying factorial design experiment, which have following interested parameters: welding current at 80, 90, and 100 Amps, welding speeds at 250, 300, and 350 mm/min, and shield gas of 75% Ar + 25% CO2, 70% Ar + 25% CO2 + 5% O2 and 69.5% Ar + 25% CO2 + 5% O2 + 0.5% He gas. The study was done in following aspects: ultimate tensile strength and elongation. A research study of ultimate tensile strength found that main factor effect, which had the highest strength to AISI 304 welding was shield gas of 70% Ar + 25% CO2 + 5% O2 at average of 954.81 N/mm2. Result of the highest elongation was showed significantly different at interaction effect between shield gas of 69.5%Ar+25%CO2+5%O2+.5%He and welding speed at 250 mm/min at 47.94%.Keywords: Austenitic Stainless Steel AISI 304/ Mechanical Property/ Welding Gas Shield/ Gas Shield
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18362552 Preparation of Metallic Copper Nanoparticles by Reduction of Copper Ions in Aqueous Solution and Their Metal-Metal Bonding Properties
Authors: Y. Kobayashi, T. Shirochi, Y. Yasuda, T. Morita
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This paper describes a method for preparing metallic Cu nanoparticles in aqueous solution, and a metal-metal bonding technique using the Cu particles.Preparation of the Cu particle colloid solution was performed in water at room temperature in air using a copper source (0.01 M Cu(NO3)2), a reducing reagent (0.2 - 1.0 M hydrazine), and stabilizers (0.5×10-3 M citric acid and 5.0×10-3 M cetyltrimethylammonium bromide). The metallic Cu nanoparticles with sizes of ca. 60nm were prepared at all the hydrazine concentrations examined. A stage and a plate of metallic Cu were successfully bonded under annealing at 400oC and pressurizing at 1.2 MPa for 5min in H2 gas with help of the metallic Cu particles. A shear strength required for separating the bonded Cu substrates reached the maximum value at a hydrazine concentration of 0.8M, and it decreased beyond the concentration. Consequently, the largest shear strength of 22.9 MPa was achieved at the 0.8 M hydrazine concentration.
Keywords: Aqueous solution, Bonding, Colloid, Copper, Nanoparticle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 56572551 An Effective Method for Audio Translation between IAX and RSW Protocols
Authors: Hadeel S. Haj Aliwi, Saleh A. Alomari, Putra Sumari
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Nowadays, Multimedia Communication has been developed and improved rapidly in order to enable users to communicate between each other over the Internet. In general, the multimedia communication consists of audio and video communication. However, this paper focuses on audio streams. The audio translation between protocols is a very critical issue due to solving the communication problems between any two protocols, as well as it enables people around the world to talk with each other at anywhere and anytime even they use different protocols. In this paper, a proposed method for an audio translation module between two protocols has been presented. These two protocols are InterAsterisk eXchange Protocol (IAX) and Real Time Switching Control Protocol (RSW), which they are widely used to provide two ways audio transfer feature. The result of this work is to introduce possibility of interworking together.
Keywords: Multimedia, VoIP, Interworking, InterAsterisk eXchange Protocol (IAX), Real Time Switching Control Criteria (REW)
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15122550 CMOS Solid-State Nanopore DNA System-Level Sequencing Techniques Enhancement
Authors: Syed Islam, Yiyun Huang, Sebastian Magierowski, Ebrahim Ghafar-Zadeh
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This paper presents system level CMOS solid-state nanopore techniques enhancement for speedup next generation molecular recording and high throughput channels. This discussion also considers optimum number of base-pair (bp) measurements through channel as an important role to enhance potential read accuracy. Effective power consumption estimation offered suitable range of multi-channel configuration. Nanopore bp extraction model in statistical method could contribute higher read accuracy with longer read-length (200 < read-length). Nanopore ionic current switching with Time Multiplexing (TM) based multichannel readout system contributed hardware savings.
Keywords: DNA, Nanopore, Amplifier, ADC, Multichannel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29322549 Micro-Study of Dissimilar Welded Materials
Authors: E. M. Anawa, A. G. Olabi
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The dissimilar joint between aluminum/titanium alloys (Al 6082 and Ti G2) were successfully achieved by CO2 laser welding with a single pass and without filler material using the overlap joint design. Laser welding parameters ranges combinations were experimentally determined using Taguchi approach with the objective of producing welded joint with acceptable welding profile and high quality of mechanical properties. In this study a joining of dissimilar Al 6082 / Ti G2 was resulted in three distinct regions fusion area in the weldment. These regions are studied in terms of its microstructural characteristics and microhardness which are directly affecting the welding quality. The weld metal was mainly composed of martensite alpha prime. In two different metals in the two different sides of joint HAZ, grain growth was detected. The microhardness of the joint distribution also has shown microhardness increasing in the HAZ of two base metals and a varying microhardness in fusion zone.
Keywords: Micro-hardness, Microstructure, laser welding, dissimilar jointed materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17632548 PSO-based Possibilistic Portfolio Model with Transaction Costs
Authors: Wei Chen, Cui-you Yao, Yue Qiu
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This paper deals with a portfolio selection problem based on the possibility theory under the assumption that the returns of assets are LR-type fuzzy numbers. A possibilistic portfolio model with transaction costs is proposed, in which the possibilistic mean value of the return is termed measure of investment return, and the possibilistic variance of the return is termed measure of investment risk. Due to considering transaction costs, the existing traditional optimization algorithms usually fail to find the optimal solution efficiently and heuristic algorithms can be the best method. Therefore, a particle swarm optimization is designed to solve the corresponding optimization problem. At last, a numerical example is given to illustrate our proposed effective means and approaches.Keywords: Possibility theory, portfolio selection, transaction costs, particle swarm optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15342547 Exergy Analysis of Reverse Osmosis for Potable Water and Land Irrigation
Authors: M. Sarai Atab, A. Smallbone, A. P. Roskilly
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A thermodynamic study is performed on the Reverse Osmosis (RO) desalination process for brackish water. The detailed RO model of thermodynamics properties with and without an energy recovery device was built in Simulink/MATLAB and validated against reported measurement data. The efficiency of desalination plants can be estimated by both the first and second laws of thermodynamics. While the first law focuses on the quantity of energy, the second law analysis (i.e. exergy analysis) introduces quality. This paper used the Main Outfall Drain in Iraq as a case study to conduct energy and exergy analysis of RO process. The result shows that it is feasible to use energy recovery method for reverse osmosis with salinity less than 15000 ppm as the exergy efficiency increases twice. Moreover, this analysis shows that the highest exergy destruction occurs in the rejected water and lowest occurs in the permeate flow rate accounting 37% for 4.3% respectively.
Keywords: Brackish water, exergy, irrigation, reverse osmosis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9492546 A New Approach For Ranking Of Generalized Trapezoidal Fuzzy Numbers
Authors: Amit Kumar, Pushpinder Singh, Parampreet Kaur, Amarpreet Kaur
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Ranking of fuzzy numbers play an important role in decision making, optimization, forecasting etc. Fuzzy numbers must be ranked before an action is taken by a decision maker. In this paper, with the help of several counter examples it is proved that ranking method proposed by Chen and Chen (Expert Systems with Applications 36 (2009) 6833-6842) is incorrect. The main aim of this paper is to propose a new approach for the ranking of generalized trapezoidal fuzzy numbers. The main advantage of the proposed approach is that the proposed approach provide the correct ordering of generalized and normal trapezoidal fuzzy numbers and also the proposed approach is very simple and easy to apply in the real life problems. It is shown that proposed ranking function satisfies all the reasonable properties of fuzzy quantities proposed by Wang and Kerre (Fuzzy Sets and Systems 118 (2001) 375-385).Keywords: Ranking function, Generalized trapezoidal fuzzy numbers
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27182545 Layout Design Optimization of Spars under Multiple Load Cases of the High-Aspect-Ratio Wing
Authors: Yu Li, Jingwu He, Yuexi Xiong
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The spar layout will affect the wing’s stiffness characteristics, and irrational spar arrangement will reduce the overall bending and twisting resistance capacity of the wing. In this paper, the active structural stiffness design theory is used to match the stiffness-center axis position and load-cases under the corresponding multiple flight conditions, in order to achieve better stiffness properties of the wing. The combination of active stiffness method and principle of stiffness distribution is proved to be reasonable supplying an initial reference for wing designing. The optimized layout of spars is eventually obtained, and the high-aspect-ratio wing will have better stiffness characteristics.
Keywords: Active structural stiffness design theory, high-aspect-ratio wing, flight load cases, layout of spars.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1112