bluuebunny/crossref_metadata_2025 huggingface dataset:
Sand Soil Properties as the Sea Embankment Material Used in Pipe-Bag Riding Method
Authors: Zhang Xuan , He Liang De , Zhuang Ning
Published: March 2012

Comparing with the stability demands of construction material used in pipe-bag riding technology for sea embankments, and based on many site and laboratory tests of sand distributed in Dongtai offshore, Northern Jiangsu Province in China for reclamation engineering, the type of sand, mechanical composition, grain shape, coefficient of permeability and liquefaction potential of sands were discussed. Additionally, the sea embankment slope stability analysis and seepage stability analysis demonstrate the sands can be used in sea embankment construction for pipe bag method
Effect of Selected Priority Rules on Manufacturing Objectives in Scheduling
Authors: Važan Pavel , Škamla Michal , Jurovatá Dominika , Ľupták Vladimír
Published: March 2012

In this paper, the effect of selected priority rules of scheduling is presented. This effect has been studied for chosen scheduling objectives by simulation method. The authors used the simulator Witness to experimentation with priority rules in a designed manufacturing system. The results of experiments have been processed into the synthesis of knowledge. The implementation of scheduling procedure is described in this paper.
Determining Production Schedule with Resource Constraints Using Drum-Buffer-Rope (DBR) Approach
Authors: Chang Ping Yu
Published: March 2012

In wafer plants, product will be manufactured through same process with different setups and specifications. This special manufacturing process is described as re-entrant flows. In photo process of wafer manufacturing, products is also restricted to be processed through same machine in each reentrance to improve quality. This phenomenon will cause scheduling in photo process being complicated and is proved to be a NP-hard problem. This research develops a mathematical model for photo process to minimize the makespan. A feasible solution is achieved using DBR (drum-buffer-rope) method. The results are compared to the optimal solution that is achieved using branch and bound algorithm. Our results show that DBR based method achieves a near optimal solution in shorter time. The results also indicate that DBR method can be useful in production scheduling with resource constraints.
Investigation of Critical Issues in a Micro and Small Scale Industries in India
Authors: Vincent Jeshvin , Hariharasudhan H. , Gopinath S.
Published: March 2012

The paper deals with the different critical issues faced by micro and small industries in India. MSE are the base for any country and contribution of MSE in India is around 10% of total GDP. The investigation was done through case study approach by surveying 20 different MSE of manufacturing organization. This research paper brings the different issues in MSE and categorically mitigation strategies were suggested.
3-D Modeling & Numerical Simulation of Friction Stir Welding Process
Authors: Roy Barnik Saha , Saha Subhash Chandra , Deb Barma John
Published: March 2012

A 3D thermal pseudo mechanical model formulated in an Eulerian frame considering a quassisteady approach to Friction Stir welding modeling of AA6061 Aluminium alloy is proposed and implemented using nonlinear finite element code in Comsol Multiphysics v 4.1. The effect of different operating parameters on the temperature distribution was analyzed. The material flow is found to be enhanced with the increase in traverse speed and angular velocity of the pin with a pronounced swirl on the advancing side. The distribution of equivalent plastic strain and dynamic viscosity was found to correlate with the distribution of the microstructure zones in the weld.
Hyperspectral Blind Unmixing and Multiple Target Detection Using Linear Mixture Model
Authors: Mushtaq Qaisar , Haq Ihsan Ul , Ahmad Muhammad , Sohaib Muhammad
Published: March 2012

In this paper a blind source separation technique Joint Approximate Diagonalization of Eigen-matrices (JADE) is investigated to unmixing and multiple target detection for hyperspectral imagery data. Our targeted minerals are Alunite, Buddingtonite, Calcite and Kaolinite in ‘Cuprite’ scene data that has been widely used for research experiments in hyperspectral imagery. A comparative study is conducted to show the effectiveness of the JADE with Vertex Component Analysis. The results are evaluated with both full and reduced bands.
Numerical Simulation on Static Performance of Savonius Rotor Based on Different Turbulence Models
Authors: Li Yan , Chai Jun Rui , Dang Fa Ning , Feng Fang , Tian Wen Qiang
Published: March 2012

With the advance of computer technology, numerical simulations were widely used for designing wind turbine. Savonius rotor is a kind of drag type wind turbine often used for water pumping for its good torque performance. In this study, numerical computations were carried out based on three different turbulence models including Splart-Allaras (S-A) model, k-εmodel and k- ωmodel to compute the static torque performance at different attack angles. Flow fields around the Savonius rotor were obtained. Comparing the computation results with the experimental results, the effects of turbulence models on the static performances of the Savonius rotor were discussed. The simulation result based on k-ω model was in agreement with test data generally.
Emotion Speech Recognition under Sadness Conditions
Authors: He Liang , Guo Long Hui , Li Huai Zhong
Published: March 2012

Sadness, one of the negative emotions, may cause undesirable impact to the daily life. Therefore, it is desirable to automatically detect sadness emotion in human-machine interactions in order to adopt measures to impair the negative effects caused by it. Speech is one of the means used by human to express emotions, therefore, it is reasonable to detect sadness emotion using speech samples. In this paper, we analyzed relevant speech features, and proposed an improved Back Propagation (BP) network for sadness recognition. The experimental results show that the improved BP network proposed has better performance than traditional BP networks in detecting sadness emotion.
Optimization of Anodic Layer and Fabrication of Organic Light Emitting Diode
Authors: Gopalakrishnan N. , Gowrishankar Subramaniam , Devidas T.R. , Balakrishnan L.
Published: March 2012

Ga doped ZnO (GZO) films of different concentrations (1, 2 and 4 mol%) have been deposited on glass substrates by RF magnetron sputtering. The grown layers at room temperature have been subjected to structural, optical and electrical characterization. It has been found that 2 mol% Ga doped ZnO has best structural, optical and electrical properties which has been used as anode layer for the fabrication of Organic Light Emitting Diode (OLED). The Zn0.98Ga0.02O film was then deposited at a lower working pressure of 0.015 mbar to obtain a good carrier concentration. The OLED structure has been fabricated with best GZO as anode layer, [N, N*-Diphenyl N, N*-Di-p-Tolylbenzene-1] as hole emitting layer and (Alq3) as electron transport layer. The fabricated OLED device has been subjected to current-voltage characteristics.
MFC + GE + GPS-Based Old and Valuable Trees Management Information System Design and Research
Authors: Zhang Yue , Xu Yan Feng
Published: March 2012

Management Information System (MIS) is an Integration information systems engineering of computer technology and network communications technology. It can be more accurate, timely, comprehensive, detailed record of the data, while further processing of all kinds of information. In this paper, MFC, GPS and GE (Google Earth) technology is used in managing Old and Valuable Trees information, to solve a series of existing problems of labor management. At the same time of improving the efficiency of information management, it can achieve the implementation of monitoring and tree information Virtual Tour by combination in GPS the point marked and Google Earth software.
Light Absorption and Structural Properties of TiO2-AgCl Thin Films Doped with Cu by Sol-Gel Process
Authors: Sangchay Weerachai , Sikong Lek , Kooptarnond Kalayanee
Published: March 2012

TiO2-AgCl thin films doped with Cu were prepared by sol-gel and coated on glass slide by dip coating process. The prepared thin films were synthesized at the temperature of 400 ◦C for 2 h with a heating rate of 10◦C/min. The microstructures of synthesized thin films were characterized by XRD, AFM and SEM. Finally, the light absorption property was evaluated by UV-vis diffuse reflectance spectroscopy. The results show all samples have the thickness in range of 200-250 nm and surfaces are dense with a large surface area. It was found that Cu doping has an effect on light absorption and structure properties of the synthesized thin films. It can be noted that TiO2-AgCl-5Cu thin films showed the highest light absorption (2.50%) under UV irradiation.
Characterization of Chitin Extracted from Waste Sources via XRD, FTIR, and TGA Techniques
Authors: Basosidik Suraida , Pankaew Piyapong , Hoonnivathana Ekachai , Limsuwan Pichet , Naemchanthara Kittisakchai
Published: March 2012

This work presents the chitin preparation from waste sources, the chitin powders were successfully extracted from shrimp shell, crab shell and squid pen. To prepare chitin powders, all raw materials were washed and grounded using agate mortar, which the particle size of powder is 212–250 μm. Then, the powdered materials were immersed into solution of chloroform and methanol (with 2:1 ratio) at room temperature for removing fat. The deprotienation and decarbonation, the samples were immersed in 50 wt% of NaOH solution for 24 h and in 4 wt% of HCl for 1 h, respectively. The XRD, FT-IR and TGA techniques were used to indicate the different characteristic between α-chitin and β-chitin prepare.
Investigation on the Effect of Process Parameters on Hardness of Components Produced by Direct Metal Laser Sintering (DMLS)
Authors: Naiju C.D. , Annamalai K. , Manoj P.K. , Ayaz K.M.
Published: March 2012

Direct metal laser sintering (DMLS) is one of the methods in layer manufacturing technologies by which metal powder can be directly used to produce both prototype and production tools. The components manufactured by DMLS should have essential hardness for its application in the industry. This study was carried out to determine the optimum process parameters influencing the hardness of the components produced by DMLS. Sintering speed, hatch spacing, post contouring, infiltration and hatch type are the process parameters taken up for study. Statistical design of experiments using Taguchi’s orthogonal array was employed for this study. The experimental data obtained were analyzed using ANOVA. From the results, it is found that one of the process parameters; scan spacing affects the hardness of the parts produced by this technology to a significant extent.
Study on the Effect of Process Parameters on Sliding Wear Behavior of Components Produced by Selective Laser Sintering (SLS)
Authors: Naiju C.D. , Annamalai K. , Kurian Joseph , George Tarun Thomas
Published: March 2012

This work presents the results of a study carried out to determine the sliding wear behavior and its effect on the process parameters of components manufactured by selective laser sintering (SLS). A standard procedure and specimen had been used in the present study to find the wear behavior. Using Taguchi’s experimental technique, an orthogonal array of L4 had been developed. Sliding wear testing using pin-on-disk machine was carried out and analysis of variance (ANOVA) technique was used to investigate the effect of process parameters and to identify the main process parameter that influences the properties of wear behavior on the SLS components. It has been found that scan spacing had more influence on wear as compared to other selected process parameters, slice thickness and infiltration.
Preparation and Properties of Urethane Oil from Jatropha Oil
Authors: Onusa Saravari , Sun Praditvatanakit
Published: March 2012

In this study, jatropha oil was reacted with glycerol and toluene diisocyanate to obtain urethane oil at hydroxyl to isocyanate ratio of 1:0.8 with methanol acting as a blocking agent. The prepared urethane oil was characterized for molecular weight and its properties were determined and compared with those of the linseed oil-modified and commercial urethane oils. It was found that the jatropha-modified urethane oil was a yellowish viscous liquid with a number-average molecular weight of 2,673. The urethane oil prepared from jatropha oil took longer time to dry than the linseed oil-modified and commercial urethane oils. Results showed that the film properties of the jatropha-modified urethane oil were comparable to those of the commercial urethane oil. The film exhibited good hardness, excellent flexibility and adhesion, and high impact strength. Additionally, it also showed excellent water resistance but only fair alkali resistance.
p-HEMA Membrane Fabrication Applying Nanogold for Biochemical Sensor
Authors: Sundari Rita , Yosfiah M. Rusli
Published: March 2012

A p-HEMA (poly-hydroxy ethyl methacrylic acid) membrane using alcohol oxidase deposited on a carbon screen printed electrode (SPE) as working electrode for amperometric transducer has been built for biochemical sensor. Acetophenon derivate has been applied to generate polymeric cross linking while ferrocene mediator has been added to wire the electrochemical reaction. The UV photocuring attached the membrane polymer onto the carbon SPE. This study has obtained that nanogold application enhanced the formaldehyde biosensor performance. Optimum result using cyclic voltametric (CV) mode in amperometric assay has been found by applying 1.6% acetophenon, 1% ferrocene, 7.7u alcohol oxidase and 0.2% nanogold in phosphate buffer of pH 7.2 at 500s UV photocure.
Optimization of Synthesis of Carbon Nanotubes Using Chemical Vapor Deposition Method
Authors: Kasim Noor Azilah Mohd , Jamal Siti Hasnawati , Sobri Shafreeza , Janudin Nurjahirah
Published: March 2012

Multi walled carbon nanotubes (MWCNTs) were synthesized using floating catalyst-chemical vapor deposition (FC-CVD) with ferrocene and benzene as catalyst and carbon source, respectively. Argon was used as a purging gas while hydrogen was used as a carrier gas. Hydrogen flow rate, reaction time and reactor temperature were varied to obtain high yield and purity of MWCNTs. The morphology and microstructures of MWCNTs produced were studied using Scanning Electron Microscopy (SEM). It was found that the maximum yield and purity of MWCNTs were produced at hydrogen flow rate of 300 ml/min with reactor temperature of 900°C and reaction time 45 minutes. It was observed that the MWCNTs are film-like, randomly oriented and in some cases entangled with uniform diameter.
Performance Study of Humidity Adsorbent Prepared from Waste Shells
Authors: Rattanachoung Nopporn , Pankaew Piyapong , Hoonnivathana Ekachai , Suttisiri Noppadon , Limsuwan Pichet , Naemchanthara Kittisakchai
Published: March 2012

CaO samples prepared from calcining the powdered waste shells at 1300°C for 4 h were tested the efficiency of humidity adsorption. The samples were characterized via X-ray diffraction (XRD) and Fourier transform infrared analysis (FT–IR) to identify the characteristic of CaO after humidity adsorption test. The results indicate that duck eggshells are highest capable of humidity adsorption while hydration rate of chicken eggshells is rather equal to that of cockle shells, and lowest hydration rate was found with sample prepared from Mussel shells. Therefore, we can conclude that the waste shells are suitable to be use as humidity adsorbent for commercial in the future
Doped Zinc-Organic Framework for Sensing of Pesticide
Authors: Kumar Pawan , Kumar Parveen , Deep Akash , Bharadwaj Lalit M.
Published: March 2012

Basolite Z-1200 is one of the most popular commercially available MOF for the gas storage applications. Pristine Basolite Z-1200 is an electrically non-conducting material. This research focuses to tap the potential of Basolite Z-1200’s unique porous structure for the adsorption and sensing of a pesticide. For this, the above said MOF has been treated with mineral acids (HCl) to make it electrically active. The protonated MOF solutions have been used to form conducting thin films on glass slides. Electrical measurements have indicated that the proton doping reduces the overall resistance of the MOF. Prepared thin films have been used to sense Mecoprop some in sample solutions. Conducting MOF thin films may find applications in environmental sensors, pre-concentration, solid phase extraction, electronic devices etc.
Offline Data Sharing Model Based on Encrypted XML Files
Authors: Weng Wen Yong , Su Jian , Yang Xiao Jie , Wang Zhe Bing
Published: March 2012

A confidentiality system generally needs to operate under a non-network environment. Hence, the adoption of an offline model is necessary to realize data sharing. An offline data-sharing model based on encrypted Extensible Markup Language (XML) files is designed. The combination of various techniques, such as XML mode, XML encryption, and XML signature, and the introduction of the Security Solution Support Center enable the proposed model to achieve a safe point-to-point data interactive mode and a security-based software module. The software system based on this model can ensure that data files generated from the data provider could only be identified and verified by the authorized data receiver.
Lead Price Forecasting Based on ARIMA Model
Authors: Lu Lin Lin , Ma Xin , Wang Ya Xuan , Yu Gen Bo
Published: March 2012

The time series ARIMA (3,1,4) model was established, which is taken into use of price forecasting. Then the forecasted price was applied to mining technical and economic index optimization study. Lead prices could be reliably predicted by time series ARIMA model, which had a high accuracy and the percentage of prediction error was 2.97% on average. It can solve the problems of the price data lag in the study of mine economic index optimization very well.
Determination of Leagile Supply Chain Index Using Fuzzy ANP Approach
Authors: Vinodh S. , Raj S. Aravind
Published: March 2012

The contemporary manufacturing industries highly depend upon the change in customer needs and also focus on their varying demands across the supply chain. The uncertain demand and supply factor paves the successful supply chain of the manufacturing organization. The manufacturing organizations themselves imply many quality principles to withstand in the competitive market. This article deals with the selection of best suitable alternative for the case supply chain using Fuzzy Analytical Network Process (ANP). The advantage of using Fuzzy ANP is the selection of best suitable alternative by considering various interdependent values across the supply chain and also overcome vagueness associated with the computation.
The Necessity of Implementation of Operations Research for Managers for Decision-Making and Productivity Increase in Production
Authors: Amoli Mohammad Khorasani , Talebzadehhosseini Seyyedmilad , Salehi Morteza
Published: March 2012

In today world, decision-making has been converted into a vital issue for managers such that in some conditions, managers are encountered with some cases which correct decision- making guarantees the survival of company. Operations research is among the sciences which in direction for decision-making, helps the managers quantitatively and using of mathematical models which are called linear programming. In this paper, it is addressed to the significance and the role of operations Research in decision-making of managers and a definition about operations research is presented and two mathematical models are presented to help the decision-making of managers to provide customers orders with the least wastes and determination of human force and over-working.
Design and Implementation of 1-Wire Bus Slave Device Based on MSP430 MCU
Authors: Zhang Chen , Xia Yu Ming , Wang Wei Dong , Zhang Cheng Lian , Xu Zhi Qiang
Published: March 2012

This paper designs the hardware and software interface of the 1-Wire slave device based on MSP430 MCU. It gives the hardware circuit schematic and the software flow, describes the working principle. The design of hardware is very easy to use and the costs are low because the hardware of the 1-Wire bus slave device includes a MSP430 MCU and some ordinary components only. The software is easy to program and expends its function so for different purposes. By this design, the scope of application of 1-Wire bus is expended. The device has none interface of 1-Wire bus can communicate with MSP430 first and then communicate with master by the simulative 1-Wire bus slave device interface based on MSP430. If system has used 1-Wire device, using this design could reduce the complexity because need not use other information protocol.
Foliar Image Color Features for Rubber Nitrogen Deficiency Status Analysis
Authors: Yao Xiao Ming , Luo Wei
Published: March 2012

Many researchers have shown for decades that there is strong correlation between foliar color and its nitrogen nutrition status. However, their results also proved the big difference of this correlation among different crops or plants. In this paper, foliar image color features especially for rubber nitrogen nutrition status analysis are presented by comparative studies on current color feature indexes. Experimental results have shown that the ratio of red or green component to the blue component with detection rate of more than 98% is more suitable for rubber nitrogen nutrition analysis than any other correlations.
Design of Wireless Heat Automatic Reading Meter Monitoring System
Authors: Xie Hao Fei , Chen Qing Hua , Wang Ping
Published: March 2012

As the whole world values the energy-saving very highly, a monitoring system, which can monitor the precise heat consumption data and schedule on demand in time, is urgently needed. This paper presents a master station monitoring system of wireless heat automatic reading meter system (named as WiHeat-AMRS). It is mainly used for residential district heat-supply system whose main function is measuring heat, charging for heat, and monitoring the running status of the whole heat system. The master station monitoring system, which was designed and implemented by the author own, consists of two parts: monitoring component and back-end database. The paper focuses on the design of both monitoring component and back-end database structure. The monitoring component collects the data of each heat meter via a wireless gateway, analyzes those data, store in the database, and achieves the automated management of heat system. Meanwhile, the master station monitoring system has been put into service by our cooperative, and has gotten great reviews.
Application of Taguchi Optimization Method in Active Vibration Control of a Smart Beam
Authors: Akbarzadeh Alireza , Fallah Mohsen , Mahpeykar Navid , Nabavi Nader
Published: March 2012

Cantilevered beams can serve as a basic model for a number of structures used in various fields of industry, such as airplane wings, turbine blades and robotic manipulator arms.In this paper, the active vibration control of a smart cantilevered beam with a piezoelectric patch is studied. Additionally, the optimization of influential parameters of piezoelectric actuator for the purpose of vibration suppression is performed. Initially, the finite element modeling of the cantilevered beam and its piezoelectric patch is described and the implementation of a control system for vibration suppression is introduced. Transient response of the system under impact loading, with and without controller, is simulated using ANSYS. Taguchi’s design of experiments method is used to investigate the effect of five geometric parameters on the vibrational behavior of the system. It is shown that, optimal selection of levels for geometry of the piezoelectric actuator and sensor, can dramatically improve the dynamic response of the smart beam.
Fuzzy Adaptive Output Tracking Controller for a Class of Chaotic Systems
Authors: Ghasemi R. , Menhaj M.B. , Abdi B.
Published: March 2012

This paper proposes a new method for designing a fuzzy adaptive controller for a class of non-affine nonlinear chaotic systems in which functions of the systems are unknown. The proposed method is aimed on a class of non-canonical non-affine nonlinear chaotic systems. The stability of the closed loop system is guaranteed based on Lyapunov’s theory. The proposed controller is robust against uncertainties and external disturbances. The simulation results show the effectiveness of the proposed method.
Analysing Reliability Aspects of HVAC Systems - A Case
Authors: Sharma Rajiv Kumar , Parbhot Chandan , Thakur Sidhant , Thakur Vivek
Published: March 2012

The general objective of this work is to analyze the failure of HVAC components in metro trains by using reliability assessment techniques. Various failure causes with respect to the electronic, electrical, hydraulic, pneumatic, software and mechanical components were identified. To improve upon the reliability characteristics of the system, in depth qualitative analysis of all HVAC units is carried out using Root cause analysis (RCA) and failure modes and effect analysis (FMEA) by listing all possible failure modes and their possible causes. Based on FMEA of components, Risk Priority Number (RPN) is calculated.
Dynamic Analysis and Experiment Research of the Two-Mass Feeder
Authors: Li Zhan Jiang , Chen Fei
Published: March 2012

In this paper, we make a theoretical analysis for the two-mass feeder. The dynamic model of the two-mass feeder is established. According to the analysis of vibration equations, the reasons that lead to forward and backward swing of the feeder are found. We collect a large number of experimental data in order to verify the correctness of the theoretical analysis, and give the corresponding improvements. The results provide a strong scientific basis for the examiner and the improvement of structural design, making the design become more rational.
Ferromagnetism, Raman Spectra and Photoluminescence of Sn0.91Co0.05Ce0.04O2 and Sn0.91Fe0.05Ce0.04O2 Nanorods
Authors: Kaur Jasneet , Kotnala R.K. , Gupta Vinay , Verma Kuldeep Chand
Published: March 2012

In the present work, we have fabricated Sn0.91Co0.05Ce0.04O2 (SCC54) and Sn0.91Fe0.05Ce0.04O2 (SFC54) nanorods by a chemical route similar to sol-gel method. X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, photoluminescence (PL) and magnetic measurements are used to characterize these nanorods. XRD pattern shows the polycrystalline nature of rods and TEM confirms that the diameter of rods lie in the range of 15-20 nm and length 100-200 nm. It is observed that on Ce3+ co-doping, nanoparticles assembled themselves into rod like structures. The SCC54 and SFC54 specimens exhibit room temperature ferromagnetism. Their saturated magnetic moment and phase transition temperature is sensitive to their size and stoichiometric ratio. Raman spectroscopy shows an intensity loss of classical cassiterite SnO2 vibration lines, which is indication of significant structural modifications like crystallinity and nano metric size effects on the vibrational properties. From PL spectra, an intense blue luminescence centred at a wavelength of 532 nm is observed in the prepared SnO2 nanostructures, attributed to oxygen-related defects, introduced during the growth process.
Effect of the Two-Step Solution Heat Treatment on the Microstructure of Semisolid Cast 7075 Aluminum Alloy
Authors: Kongiang Saowalak , Plookphol Thawatchai , Wannasin Jessada , Wisutmethangoon Sirikul
Published: March 2012

Effect of the two-step solution heat treatment on the microstructure of semisolid cast 7075 aluminium alloy has been studied. The microstructure of the as-cast specimens mainly consisted of matrix-α (Al) and grain boundary (GB)-eutectic phase (α-Al + Mg(Zn,Cu,Al)2). After solution treating, coarse black particles were found to form in the single-step solution treated specimens at the condition of 450 °C for 8 h and 480 °C for 1 h, respectively. Two-step solution heat treatment resulted in the reduction of coarse black particle formation while maintaining the same amount of eutectic MgZn2 phase dissolution as the high temperature single-step solution treatment. Therefore, the two-step solution heat treatment enables alloying elements dissolved into the matrix without overheating and hence decreases coarse black particles. The optimum two-step solution heat treatment condition derived from this study was 400 °C for 8 h + 450 °C for 4 h.
Influence of Polypropylene Fiber in Strength of Foamed Concrete
Authors: Hadipramana Josef , Samad Abdul Aziz Abdul , Zhao Zi Jun , Mohammad Noridah , Wirdawati W.
Published: March 2012

Foamed concrete is material that can be used in wide range of constructions and produced in high density. This investigation examined effect of chopped Polypropylene Fiber (PF) that mixed into admixture concerning strength of foamed concrete high density. Mechanical test were performed to measure effect of PF on improving compressive and splitting tensile strength. Result indicate that PF significantly improving compressive strength and behavior of PF where drawn into foamed concrete similarly with normal concrete. The fibrillated PF has been occurred and reduced the micro crack of matrix and prevented propagation crack growth. The presence of PF improved splitting tensile strength was not significantly. Influence of porous of foamed concrete is considered. Scanning Electron Microscope (SEM) exhibits condition microstructure of foamed concrete reinforced PF that alter microstructure, especially interfacial bonding due to PF presence.
Compositions and Particle Sizes of (RE)Ba2Cu3O7-X Superconductor Powders Synthesized by the Solution Combustion Technique
Authors: Jongprateep Oratai , Tangbuppa Pimsiri , Manasnilobon Nattawan
Published: March 2012

Superconducting compounds (RE) Ba2Cu3O7-x (RE = rare earth such as Y, Er, Sm and Nd) can be exploited in various industrial applications such as cables, electric motors and energy storage systems. The project aimed at synthesizing fine-particle YBa2Cu3O7-x, ErBa2Cu3O7-x, SmBa2Cu3O7-x and NdBa2Cu3O7-x, powders with compositions suitable for the applications. Solution combustion technique was employed in the synthesis, using urea as fuel. Compositional analysis obtained from x-ray diffraction indicated that the as-synthesized powders contained the desired (RE)Ba2Cu3O7-x (RE123) superconducting phase and impurities, including (RE)2BaCuO5 (RE211), BaCO3 and Ba(NO3)2. However, majority of the impurities were eliminated when the powders were calcined at 900°C. Only (RE)Ba2Cu3O7-x (RE123) and (RE)2BaCuO5 (RE211) phases remained after calcination. Results from scanning electron microscope showed that the as-synthesized powders obtained from the solution combustion technique had relatively small particles with average particle size of 0.67 micrometers, while the calcined powders exhibited coarsening effects with average particle size of 4.4 micrometers.
Bulk Crystallization of Ceramic Whiskers from Borate-Based Glass
Authors: Sooksaen P. , Kannasute S. , Larbmark K. , Maneelada C.
Published: March 2012

Bulk crystallization of B2O3-SiO2-Al2O3-BaO-MgO glass system was investigated. Controlled heat treatment process was carried out between 900 and 1200°C to form glass-ceramics. Phase evolution in the crystallized glasses was studied by X-ray diffraction. Microstructures of the chemically etched surfaces were revealed by scanning electron microscope and micro-hardness was measured by Vickers hardness tester. High aspect ratio of aluminium borate whiskers were in the nano to micro regime and dispersed within the residual glass matrix. Whiskers had different sizes and compositions depending on the heat treatment temperature, which affected the surface hardness of the glass-ceramics. In general, increasing heat treatment temperature led to an increase in crystal size and length as well as the surface hardness (4.8 to 5.5 GPa). The whisker crystals oriented uniformly within the residual glass matrix leading to interlocking microstructure. The synthesized glass-ceramics in this study can be applied as machinable materials in various industries because their microstructures can resist microcracking and hence increase fracture toughness.
Investigations of Tungsten Based Intermetallic Alloys by Self Propagating High Temperature Synthesis from Metal Oxide Precursors
Authors: Chanadee Tawat , Wannasin Jessada , Sutham Niyomwas
Published: March 2012

The in-situself propagating high temperature synthesis technique were used to synthesis tungsten based intermetallic alloys from WO3/SiO2/Al and WO3/B2O3/Al reactant mixture system. The reaction was carries out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The microstructure and phase distribution of the SHS reaction products were characterized by scanning electron microscopy (SEM) and energy dispersive x-ray (EDX), respectively. The results indicate that complete reaction of precursors to yield Al2O3-WSi2 and Al2O3-WB as product composites with clearly separation between Al2O3 and WB.
Effect of MgO Additive on Microstructure of Al2O3
Authors: Harun Zawati , Ismail Nur Farhani , Badarulzaman Nur Azam
Published: March 2012

In this work, the consolidation of different alumina particles via sintering process was conducted to the compacted alumina pellets. This consolidation was also assisted with the sintering aid, MgO to densify the final ceramic structure. Comparison between the influence of additive to the different particles size of compacted alumina by observing the microstructure and physical properties was conducted. The value physical properties and microstructure clearly show that for both particle size of alumina, MgO additive can increase the density value and improve microstructure properties.
Some New Results for the Study of Acoustic Radiation within a Uniform Subsonic Flow Using Boundary Integral Method
Authors: Beldi M. , Maghrebi A.
Published: March 2012

In this paper, a reformulation of the Helmholtz integral equation for tridimesional acoustic radiation in a uniform subsonic flow is presented. An extension of the Sommerfeld radiation condition, for a free space in a uniform movement, makes possible the determination of the convected Green function, the elementary solution of the convected Helmholtz equation. The gradients of this convected Green function are, so, analyzed. Using these results, an integral representation for the acoustic pressure is established. This representation has the advantage of expressing itself in terms of new surface operators, which simplify the numerical study. For the case of a regular surface, the evaluation of the free term associated with the singular integrals shows that it is independent of the Mach number of the uniform flow. A physical interpretation of this result is offered. A numerical approximation method of the integral representation is developed. Furthermore, for a given mesh, an acoustic discretization criterion in a uniform flow is proposed. Finally, numerical examples are provided in order to validate the integral formula.
Coating Life Assessment: The Use of Adhesion Strength in Parametric Development in Coating Degradation Evaluation
Authors: Prawoto Yunan , Mat Yajid Azizi , Ahmad Zaini
Published: March 2012

Most of the steel structures used in industrial and non-industrial applications are exposed to outdoors weathering conditions. Organic coating typically protects them from corrosion. The maintenance actions can be done efficiently only if there is sufficient information of the condition. Therefore, the deterioration of the coating system and its lifetime has to be assessed accurately. This paper focuses on the development of parameters based on adhesion strength useful for that purpose. Three parameters are proposed, namely stress intensity factor, strain energy density, and J-integral.
Effect of Substrate Conditions on Fe-Al2O3 Composite Coating
Authors: Saowanee Singsarothai , Rachpech Vishnu , Sutham Niyomwas
Published: March 2012

Steel substrate was coated by Fe-Al2O3 composite using self-propagating high-temperature synthesis (SHS) reaction of reactant coating paste. The green composite paste were prepared by mixing of Fe2O3, Al and polyvinyl alcohol solution. It coated on the steel substrate. The effect of sustrate conditions on the Fe-Al2O3 composite coating were studied. The SHS reaction of the coated green composite was ignited by oxy-acethylene flame. The reaction between precursors happen step by step along the coated green composite length, to form Fe-Al2O3 composite coating on the steel plate. The Fe-Al2O3 composite coating was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) couple with dispersive X-ray (EDS)
Tool Wear Performance of TiAlN/AlCrN Multilayer Coated Carbide Tool in Machining of AISI D2 Hardened Steel
Authors: Jasni N.A.H. , Lajis Mohd Amri , Kamdani K.
Published: March 2012

This paper presents the results of experimental investigation conducted on a vertical machining centre (VMC) to ascertain the effectiveness of TiAlN/AlCrN multilayer coated carbide inserts in end milling of AISI D2 hardened steel (58-62 HRC) In high-speed dry hard milling, different cutting speed (v) and radial depth of cut (dr) were applied. Tool failure modes and wear mechanisms were examined at various cutting parameters. Flank wear, chipping and breakage at cutting edge were found to be the predominant tool failure for the cutting tools. Built-up edge, adhesion and abrasive are the wear mechanisms observed on the cutting tools. The highest volume of material removed, VMR attained was 1500 mm3, meanwhile the highest tool life (T) was 4.97 min. The surface roughness, Ra values from 0.20 to 0.45 μm can be attained in the workpiece with a high volume material removed. The relationship of tool wear performance and surface integrity was established to lead an optimum parameter in order to have high volume material removed, maximum tool life as well as acceptable surface finish.
Effect of Latex Treatment on Properties of WNRL/PS Blends
Authors: Boondamnoen Orathai , Azura A. Rashid , Ohshima Masahiro , Chuayjuljit Saowaroj , Ariffin Azlan B.
Published: March 2012

The waste natural rubber latex was treated with natural rubber latex (TWNRL) prior to blend with polystyrene (PS). The blend was conducted with the ratio of 30/70, 50/50 and 70/30 TWNRL/PS using Haake internal mixer at 140 °C and 60 rpm. The waste natural rubber latex/PS (WNRL/PS) was prepared in the similar procedure. The complex modulus (E*) at various temperature and tensile properties were investigate. The tensile fracture surface was observed using Scanning Electron Microscope (SEM). The results show that the E* of WNRL/PS blends are higher at any temperature compared to TWNRL/PS blend for similar compositiondue to higher network molecules. At 30/70 blends show the tensile strength, Young’s modulus and elongation at break of TWNRL/PS are higher than WNRL/PS blend due to a better molecule entanglement. Improvement of elongation at break was shown for70/30 TWNRL/PS blend, because of the rearrangement of molecule chains under stress. The SEM observation show the successful improvement of blend morphologies by latex treatment at all composition. Moreover, the SEM micrograph also imply the fracture behavior; more tendril on fracture surface indicating the higher strain needed before failure.
Preparation and Characterization of Blended Composite Membranes
Authors: Rafiq Sikander , Man Zakaria , Maulud Abdulhalim , Muhammad Nawshad , Maitra Saikat
Published: March 2012

Composite membranes were prepared by incorporating inorganic silica nanoparticles into blends of polysulfone/polyimide (PSF/PI) membranes via sol-gel route. Morphological structures of the developed membranes were carried out by scanning electron microscopy (SEM). Spectroscopic analysis of the hybrid membranes were done by fourier transform infrared spectroscopy (FTIR) analysis. Differential scanning calorimetry (DSC) analysis shows that the glass transition temperature (Tg) increased from 209oC to 238oC in the hybrid membranes followed by thermogravimetric analysis (TGA) that showed significant improvement in thermal stability of the developed membranes.
Study on Warm and Hot Tensile Deformation Behavior and Flow Stress of AZ31B Magnesium Alloy Sheet
Authors: Li Wen Juan , Zhao Guo Qun , Ma Xin Wu , Gao Jun
Published: March 2012

The true stress-strain curves of AZ31B magnesium alloy sheet were obtained by using the uniaxial tensile tests at the temperature ranging from 50°Cto 300°C and the initial strain rate ranging from 0.001/s to 0.1/s. The influence of temperature and strain rate on the flow stress was analyzed. The results show that the flow stress decreases and the elongation in fracture increases with increasing temperature and decreasing strain rate，and the plastic performance is improved obviously. Through the analysis of the true stress-strain curves，a mathematical model of the flow stress was established based on an exponential form whose power is a quadratic function. All the coefficients in the model were fitted as functions of temperature and strain rate. The comparison of the calculated results with experimental data shows that the model established in this study can accurately reflect work hardening and strain softening effect of AZ31B magnesium alloys during the hot deformation. It can be used for the prediction of flow stress for AZ31B magnesium alloys under hot work conditions and numerical simulation of forming processes.
Fabrication and Characterization of Porous Zirconia/Alumina Composites
Authors: Nozary Gholamhossein , Roudini Ghodratollah , Farashiani Ali Akbar
Published: March 2012

Porous ZrO2-Al2O3 ceramic composites containing 0, 30 and 50 wt% Al2O3 were prepared by solid state sintering in the temperature range of 1375˚-1650°C and effect of temperature and alumina percentage on compressive strength and microstructure of monoclinic zirconia was investigated by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD results on composite samples showed monoclinic ZrO2 and Al2O3 phases. SEM images showed uniform distribution of porosity in microstructure. Compressive strength of monoclinic zirconia improved from 33MPa to 134 MPa with adding of 50%wt alumina in sintering temperature of 1650°C.
Failure Analysis of Carbon Fiber Reinforced Polymer (CFRP) Bridge Using Composite Material Failure Theories
Authors: Agusril S.T. , Mohamad Nor Norazman , Zhao Zi Jun
Published: March 2012

Portable bridges are very important for maintaining mobility in the aftermath of natural disaster or in the battlefield. This requirement has lead to the needs for light-weight bridging system for ease in launching, retracting, transporting, and storing. In this research, a foldable bridge with three sections of beam connected together using the hinges connection has been designed and analyzed. The bridge is constructed using sandwich Carbon Fiber Reinforced Polymer (CFRP) which consists of CFRP and Aluminum Honeycomb, as the skin and core, respectively. The uses of materials are expected will reduce the total weight of bridge without decreasing of overall performance. Failure theories of composite material such as Maximum Stress, Maximum Strain, Tsai-Wu and Tsai-Hill failure theories were selected to generate an allowable strength graph. From the graph, can be seen that, the material stresses are in the allowable stress-strain ranges, therefore, the bridge is capable of carrying the design load with sufficient safety factor.
Nonlinear Mechanical Analysis of Polymer Precast Panel for Temporary Support of Tunnels
Authors: Khalajmasoumi M. , Ibrahim I.S. , Mohd Yatim J. , Koloor S.S.R.
Published: March 2012

The increase of population in developed cities has improved the requirement for new advanced transportation method such as urban railway system. Therefore, the needs of developing advanced technology in the tunnelling construction for the use of underground railway system are necessary. Underground railways are one of the most accepted systems used for transporting a large amount of people in highly populated cities, which its development requires a set of advanced science such as in the tunnelling construction process. One of the significant failure may occur in tunnels is ceiling collapse. This failure is a major concern during construction to avoid hazardous for workers. In the past few decades, the combination of sprayed concrete and steel meshes (shotcrete) are utilised as temporary support for tunnels during the construction process. This was a time consuming procedure and for a team of workers, they face plenty of obstacles from safety concern to limited working space area when mounting some heavy panel inside the tunnels. To overcome these problems, an experimental test was carried out using Hard Density Polyethylene (HDPE) which is approximately has the same stiffness to shotcrete but 50% less of the weight of the structure. A rectangular beam sample of was manufactured as a precast panel and experimentally tested under three-point bending load as in the real conditions. Maximum deflection and total reaction force of the panels was recorded. The nonlinear mechanical behaviour of the specimen is analysed based on the bending stiffness. Considering the hyper-elastic behaviour of HDPE, the overall response of the sample had shown a good acceptable strength 14.3% higher than the desired strength which can approve the right material selection. In addition, discussion was given on total stiffness and reduced stiffness because of nonlinear behaviour of the HDPE. The value of strain is measured at the bottom surface of the HDPE beam along the length and width the sample for further discussion. This type of polymer can be assumed as large strain material and it is showing a large deformation under three-point bending condition which can help to inform workers about the safety of the whole structure.
Mechanical Characterization of Nanoclay Reinforced Polypropylene Composites at High Temperature Subjected to Tensile Loads
Authors: Farsani Reza Eslami , Nasab Ziba Hedayat , Khalili S. Mohammad Reza , Soleimani Neda
Published: March 2012

In this paper, Polypropylene (PP) nanocomposites are prepared by melt mixing in a twin-screw extruder by injection molding. The role of compatibilizing agent is performed by maleic anhydride grafted polypropylene (PP-g-MA) between nanoclay and PP. The effect of nanoclay particles (1, 3, 5 wt %) on the PP composites is investigated for tensile test at high temperature for the first time. Mechanical behaviors of PP/clay nanocomposites at both room temperature (RT) and high temperature (HT) are investigated in terms of tensile properties. Addition of nanoclay showed a significant enhancement in stiffness of PP/clay nanocomposites. Nearly 36% and 157% increase in the tensile modulus at both RT and HT are observed, respectively. But, the increase in tensile strength is almost negligible.
Dielectric Studies of Proton Conducting Polymer Electrolyte Based on Chitosan/PEO Blend Doped with NH4NO3
Authors: Shukur M.F. , Kadir M.F.Z. , Ahmad Z. , Ithnin R.
Published: March 2012

Polymer blend of chitosan and poly(ethylene oxide) (PEO) electrolytes were prepared by employing solution cast method. Ammonium nitrate (NH4NO3) was added to the blend to supply the charge carriers for ionic conduction. The impedance of the electrolytes was measured by electrical impedance spectroscopy (EIS) over the frequency range of 50 Hz to 1 MHz. The permittivity ɛr and electric modulus Mr of the complex were analyzed. Dispersion at low frequencies caused by space charge effect from the electrodes was observed. The modulus plots indicated that the dispersion deviated from the Debye behaviour. The relaxation time, τ decreased to 1.64 × 10-7 s as the NH4NO3 content was increased up to 40 wt.%.