bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermo-Mechanical Stress Analysis in Electronic Packaging with Continuous and Partial Bond Layer
Authors: Sujan D. , Piaw T.K. , Woldemichael Dereje Engida
Published: December 2013

Interfacial stress due to thermal mismatch in layered structure has been considered as one of the major causes of mechanical failure in electronic packaging. The mismatch due to the differences in coefficient of thermal expansion (CTE) of the materials in multi-layered structure may induce severe stress concentration to the electronic composites namely interfacial delamination and die cracking. Therefore, the studies and evaluation of interfacial stress in electronic packaging become significantly important for optimum design and failure prediction of the electronic devices. The thermal mismatch shear stress for bi-layered assembly can be analyzed by using the mathematical models based on beam theory. In this study, Finite Element Method (FEM) simulation was performed to an electronic package by using ANSYS. The shear stress growth behavior at the interface of the bonded section was studied with the considerations of continuous and partial bond layers in the interfaces. Based on the analysis, it can be observed that the partial bond layer with small center distances can be simplified as a continuous bond layer for bi-layered shearing stress model analysis.
Experimental Investigation on the Effect of Orifice Diameter and Inlet Pressure to the Ranque-Hilsch Vortex Tube Performance
Authors: Ismail Nurhasanah , Wirachman Wisnoe , Remeli Muhammad Fairuz
Published: December 2013

In this experiment, the cold mass fraction, cold temperature difference and isentropic efficiency of Ranque-Hilsch Vortex Tube were investigated and measured. Three different inlet pressures (absolute) (296633 Pa, 394699.5 Pa and 492766 Pa) and 2 type of orifice diameter (4 mm and 5 mm) were used. 5 mm orifice gives higher value of cold mass fraction (μc = 0.7067) compare to 4 mm orifice (μc = 0.3264). It is also no significant effect in cold mass fraction by changing three difference inlet pressures. 4 mm orifice has higher cold temperature difference (ΔTc = 18°C) compare to 5 mm orifice (ΔTc = 8°C) at highest inlet pressure (492766 Pa) that were used. 4 mm orifice has higher isentropic efficiency (ηisen=0.17545) compare to 5 mm orifice (ηisen=0.0834). For both orifices, the highest isentropic efficiency was obtained when the lowest inlet pressure (296633 Pa) were applied.
Investigation of Flow Uniformity and Pressure Recovery in a Turning Diffuser by Means of Baffles
Authors: Nohseth Nur Hazirah , Nordin Normayati , Othman Safiah , Raghavan Vijay R.
Published: December 2013

Turning diffuser is an engineering device that is widely used in the industry to reduce the flow velocity as well as change the direction of the flow. Having a curvature shape causes its performance to decrease in terms of pressure recovery (Cp) and flow uniformity (σu). Therefore, this study presents the work done in designing baffles to be installed in the turning diffuser with ratio of AR=2.16 to improve the flow uniformity and pressure recovery. It also aims to investigate the mechanism of flow structure and pressure recovery in turning diffusers by means of turning baffles. The results with varying inflow Reynolds number (Rein) between 5.786E+04 1.775E+05 have been experimentally tested and compared with previous study. Particle image velocimetry (PIV) was used to determine the flow uniformity. On the other hand, a digital manometer provided the average static pressure of the inlet and outlet of turning diffuser. The best produced pressure recovery of Cp=0.526 were recorded when the system were operated at the highest Reynolds number tested Rein=1.775E+05. This result shows an improvement up to 54.625% deviation from previous study with Cp=0.239. The flow uniformity also shows an improvement of 47.127% deviation from previous study at the same Rein with σu=3.235 as compared to previous study σu=6.12.
Flow Separation Prediction in a Single-Phase Flow in an Inline Tube Bundles
Authors: Sadikin Azmahani , Isa Norasikin Mat
Published: December 2013

The vertical single-phase flow was studied on the shell side of a horizontal tube bundle. In the present study, CFX version 14.0 from ANSYS was used to predict the flow regimes in the two tube bundles; i.e. the 19 mm and 38 mm arranged in an in-line configuration with a pitch to diameter ratio of 1.32. The simulations were undertaken to inform on how the fluid flowed within the tube passages in different tube bundle diameter that gives different gaps between the tubes, where the fluid must pass. The results show that the maximum gaps between the tubes have no clear effect to the flow where the flow separation and re-attachment and the average velocity is the same when increasing the tube bundle. This is consistent with other published data.
Two-Phase Flow Pressure Drop Model for a Shell Side of a Shell of Heat Exchanger
Authors: Sadikin Azmahani , Asmuin Norzelawati
Published: December 2013

This paper present a two-phase pressure drop model for a in-line tube bundle for airwater mixtures flowing through an idealised shell and tube, in-line heat exchanger. The model used momentum flux and entrained liquid fraction to predict the acceleration pressure drop. The model predicts the pressure drop well using both accelaration and gravitational pressure drop deduced from data available in open literature. The model is shown to be mass flux dependence.
Investigation on the Turbulence Models Effect of a Coal Classifier by Using Computational Fluids Dynamics
Authors: Isa Norasikin Mat , Ahmad Fara Ahmad Norman Khalis , Asmuin Norzelawati
Published: December 2013

This study evaluates five turbulence models to determine the best models to be implemented as it representing the turbulent flow inside the lab scale classifier. The models studied are: The standard ƙ-ɛ model, Renormalization-group (RNG) ƙ-ɛ model, Realizable ƙ-ɛ model, Standard k-ω model, and Reynolds stress model (RSM). Through analysis of air flow, the air velocity data can be obtained from computational fluid dynamics (CFD), the result shows that, standard ƙ-ɛ model and Realizable ƙ-ɛ model are found to be more appropriate to use than the other turbulence models. The model validation is conducted by comparing the simulated velocities with experimental data in a lab scale classifier from literature. ANSYS software is selected to be used to run the simulation and analysis.
Surface Integrity of a High Speed Milling FC300 Gray Cast Iron
Authors: Mohd Hadzley Abu Bakar , Nurul Fatin Mohamad Raffi , Raja Izamshah Raja Abdullah , Hussein Nur Izan Syahriah , Siti Sarah Ahmad , Sivarao Sivarao
Published: December 2013

The high speed machining (HSM) of gray cast iron for manufacture mold and dies involve many different cutting tool from deep hole drills to smallest ball nose end mills [. Due to the demand of fast and high productivity, high speed machining (HSM) has been increasingly used to produce mold and dies that are mostly used in automotive industry especially for stamping dies components. The process of HSM sometimes combined together with manual polishing to enhance the die surface into fine mirror finish. Although the manual polishing strongly depends by experience and skill of workers, this technique is the preferable option for polishing of moulds and dies. However, such extensive manual polishing will provide some drawback because of many human factors such as pressure and technique of polishing individual person uses. Therefore, the application high speed machining in manufacturing is still demanding as it can improve surface finishing by reducing manual polishing, reportedly account for up to 30% of the total time [2].
Contour Optimization of an Inductor Using Taguchi Method
Authors: Boo K.K. , Mark Ovinis , Nagarajan T.
Published: December 2013

The parameters and its influence on the winding design of an inductor was investigated, using Taguchis method, with the aim of selecting an optimum set of parameters. An experimental design was use to determine the optimal combination of parameters corresponding to various contour designs that would result in minimum fall out ratio and minimum machine error processing. An orthogonal array factorial run was employed to determine an optimal set of parameters and to determine the influence of parameters such as wind start post, finishing angle, winding width and winding pitch on the performance. Based on the results from the analysis, it is concluded that the winding width is the most significant parameter related to fall out ratio. Additionally, the parameter winding width will define the optimum contour design in terms of geometry of design shape.
Characterization and Rheological Studies on Ready-Made Feedstock of Stainless Steel 316L in Metal Injection Molding (MIM) Process
Authors: Mohamad Nor Nor Hafiez , Ismail Muhammad Hussain , Abu Kasim Nur Atikah , Muhamad N. , Taib M.A.
Published: December 2013

Current trend for manufacturers associated to MIM industry try to enhance the feedstock in term of its characteristics, since it is the most crucial part of the MIM process. This paper covered the characterization and rheological studies on a ready-made feedstock of stainless steel 316L which is vital to determine the availability and suit the needs of many advanced applications. There are three different experiments involved which are Scanning Electron Microscope (SEM), Differential Scanning Calorimeter (DSC), Thermogravimetric (TGA) and Capillary Rheometer. Observation through SEM gives an insight of the bonding microstructure matrices of the feedstock and also determines the homogeneity of the feedstock. DSC testing defines the melting temperature of the 3 binders used which are 62.07°C for surfactant, 178.72°C for filler and 236.61°C for backbone binder. From TGA result, it showed that the total weight loss of feedstock was 39%. Throughout the capillary rheometer testing, the feedstocks viscosity was decreasing as the shear rate increasing. The feedstock exhibits pseudoplastic behaviour since its flow behaviour index was less than 1. It is founded that at the temperature of 190°C, the feedstock exhibits the best characteristics for injection.
The Computer Modeling of the Textile Material
Authors: Podešva Jiří
Published: December 2013

The textile industry is represented not only by fashion (most popular area) but also textile material for industrial purposes. The very old use of textile materials is production of fabric bags. The deformation of such bag is the subject of computer modeling, what is the contents of the paper. The deformation of the 2D cloth layer, exposed to normal pressure, has the mathematical description in the form of the partial differential equation. The solution depends on the area, on which is searched, and on the boundary conditions. It is known only for planar circular area. The deformation of more complicated shapes (3D) must be found using computer simulations. The problem, discretized by finite element method, has the form of the system of algebraic equations. The description has non-linear character and brings a range of problems. The solution possibilities are described in the paper. Finally the solution of the 3D problem is shown.
A Squeegee Coating Apparatus for Producing a Liquid Crystal Based Bio-Transducer
Authors: Soon Chin Fhong , Goh Zai Peng , Ku Lee Chin , Lee Ten Ten , Tee Kian Sek
Published: December 2013

Cholesteryl ester liquid crystals were discovered with a new application in sensing traction forces of single cells. The liquid crystal bio-transducer is produced by manual scraping of liquid crystals onto the petri dish, in which the technique is highly subjective to the skill of the user to produce homogeneously spread liquid crystal substrates. This paper describes the development of an apparatus used to produce a liquid crystal substrate using squeegee coating technique. It consists of a biaxial mechatronic system which is synchronously controlled in vertical and horizontal directions scraping the liquid crystal substrates evenly on the surface of a petri dish. The thickness of the liquid crystal was profiled using laser diffraction technique and the homogeneity of the liquid crystal films produced was examined in a crossed-polarizing microscope. At an angular speed of 1500 rpm and under a shear stress of 1.46 ± 0.72 kPa, the squeegee coating was found producing liquid crystal films at a thickness of 132 ± 23 μm on the surface of petri dishes. With the application of this apparatus, evenly spread liquid crystal coatings with control thickness in petri dishes were consistently produced. This has overcome the major problem of manually coating the liquid crystal substrates using a cell scraper.
Integration of Value Stream Mapping with RFID, WSN and ZigBee Network
Authors: Ahmed Aftab , Hasnan Khalid , Aisham Badrul , Bakhsh Qadir
Published: December 2013

Value stream mapping (VSM) significantly monitored by integrating radio frequency identification (RFID), wireless sensor network (WSN), ZigBee wireless technologies and Labview Graphical user interface (GUI). These technologies are used for identifying, sensing, positioning, multi-hop communication and real time locating system (RTLS). Combined effect of above technologies will optimize labor and operations cost, minimize human error; improve environmental performance and information accuracy. ZigBee protocol IEEE 802.15.4 standard has been used as wireless network in variety of commercial and industrial applications. The range of tracking of RFID reader enhanced with ZigBee coordinator through ZigBee router, which overcomes the range of radio areas that do not reach signals from the RFID reader. The proposed system provides richer information of objects location, identification and their environmental status like temperature and moisture.
Hardware-in-the-Loop Simulation for Active Force Control with Iterative Learning Applied to an Active Vehicle Suspension System
Authors: Rosli Rosmazi , Mailah Musa , Priyandoko Gigih
Published: December 2013

The paper focuses on the practical implementation of a novel control method to an automotive suspension system using active force control (AFC) with iterative learning algorithm (ILA) and proportional-integral-derivative (PID) control strategy. The overall control system to be known as AFC-IL scheme essentially comprises three feedback control loops to cater for a number of specific tasks, namely, the innermost loop for the force tracking of the pneumatic actuator using PI controller, intermediate loops applying AFC with ILA strategy for the compensation of the disturbances and the outermost loop using PID controller for the computation of the desired force. A number of experiments were carried out on a physical test rig with hardware-in-the-loop simulation (HILS) feature that fully incorporates the theoretical elements. The performance of the proposed control method was evaluated and benchmarked to examine the effectiveness of the system in suppressing the vibration effect of the suspension system. It was found that the experimental results demonstrate the superiority of the active suspension system with proposed AFC-IL scheme compared to the PID and passive counterparts.
Effect of NH3 on Structural and Optical Properties of SiO2-CuO Core-Shell Nanostructure
Authors: Salim Musdalilah Ahmad , Misran Halina , Othman S.Z. , Shah N.N.H. , Razak N.A.A. , Manap Abreeza
Published: December 2013

CuO nanoparticles at ca. 20-50 nm were successfully coated on monodispersed silica spheres prepared by modified sol-gel method. A renewable palm oil based decyl-alcohol (C10) was employed as nonsurfactant surface modifier prior to coating with CuO. Various amounts of ammonia (NH3) (0-1 ml) was as catalyst during the modification process to study the effect in homogeneous deposition of CuO on silica surfaces. The homogeneous depositions of CuO on silica were achieved with the addition of 0.9 ml of NH3. The optical absorption peak and energy band gap (Eg) values were at ca. 1.8-2.18 eV suitable for semiconductor and optical sensor materials.
Basalt Fabric-Electrospun Nanofiber-Based Composite Laminates
Authors: Subagia I Dewa Gede Ary , Tijing Leonard D. , Kim Yon Jig
Published: December 2013

This study investigated the influence of electrospun polyurethane mats containing different contents of carbon nanotubes (CNTs) stacked in between basalt fabric layers to form a composite laminate. The composite laminate was fabricated using a vacuum-assisted resin transfer molding (VARTM) process. Flexural test were carried out to investigate the strength and stiffness of composites for each configuration, while the failure characteristics were observed using a field emission scanning electron microscopy (FESEM) analysis. The results showed that flexural strength and stiffness of the hybrid composites with increasing CNT content in polyurethane (PU) nanofiber were increased by 6.5% and 17.3%, respectively. Furthermore, the addition of surfactants for the dispersion of CNTs in nanofibers significantly improved the flexural property of the composite interply basalt fabric-CNT/PU laminates. This study proved that the use of multi-scale reinforcement fillers with good and homogeneous dispersion increased the mechanical performance of the composite.
The Effect of Microstructure and Mechanical Properties of Aluminium Aa6061 before and after Heat Treatment Using TIG
Authors: Ahmad Rosli , Abdulmalik Samir Sani
Published: December 2013

This work studies the effect of a post-weld heat treatment (PWHT) on the mechanical and microstructure properties of an AA6061 sample welded using Tungsten Inert Gas (TIG) method. TIG method is comparatively flexible and has good economy. The welded samples were divided into as-welded and PWHTs samples. The PWHTs samples were solution heat treatment, water quenching and artificial aging. Both welded samples were cut according to the ASTM E8M-04 standard to obtain the tensile strength and the elongation of the joints. The failure pattern of the tensile tested specimens was analysed using scanning electron microscopy (SEM). A Vickers microhardness testing machine was used to measure the hardness across the joints. From the results, the PWHTs were able to enhance the mechanical properties and microstructure characteristics of the AA6061 joints welded by the TIG method.
Biosorption of Pb(II) and Zn(II) in Synthetic Waste Water by Watermelon Rind (Citrullus lanatus)
Authors: Azizul-Rahman M.F.H , Mohd-Suhaimi A.A. , Othman Norzila
Published: December 2013

Water pollution by heavy metal is great concern due to its toxicity to nature and environment. Extensive studies were carried out to remove heavy metal through physical, chemical and biological approaches. One of the biological approaches is biosorption. This study was conducted under several conditions namely pH, biosorbent dosage, initial wastewater concentration and contact time. Final concentrations of metals were tested using Atomic Absorption Spectrometry (AAS). The results revealed that optimum removal for Lead and Zinc was 77.3% and 90.30%. Optimum pH, for Lead was 6.0 whereas Zinc was 7.0 respectively. Both metals have showed the same optimum biosorbent dosage of 0.02g and 30 minutes of contact times. Meanwhile, the optimum initial metal concentration for Lead and Zinc were 5 ppm and 1ppm. It is proven that watermelon rind is able to treat wastewater with the present of Lead and Zinc.
Simulation of Ironing Process for Earring Reduction in Sheet Metal Forming
Authors: Anggono Agus Dwi , Siswanto Waluyo Adi
Published: December 2013

Manufacturing of beverage cans is porcessed by using multi-stage ironing following deep drawing from the sheet material of aluminum and steel. An earing profiles are develops during deep drawing of cylindrical cup due to the planar anisotropic properties of sheet. Therefore, the analysis of earing is important to evaluate and control the development of earing. This paper describes a simulation of the cold ironing process in the forming cylinder cap. The ironing process in this study was focused on the prediction of height increasing, earing and thinning. Two different materials of aluminum AA5042 and AKDQ steel were selected for comparison. The results show that the increasing of cup height was in the same trend.
Potassium Bromide as Space Holder for Titanium Foam Preparation
Authors: Mat Noor Fazimah , Zain M.I.M. , Jamaludin K.R. , Hussin R. , Kamdi Z. , Ismail A. , Ahmad Sufizar , Taib H.
Published: December 2013

Titanium (Ti) alloy foam was prepared by using potassium bromide (KBr) as space holder with percentage between 20 to 40 wt.%. In this work, the potential of KBr as a new space holder was determined. The Ti alloy powder and space holder were first manually mixed before being compacted using hydraulic hand press. The green compacts were then sintered at temperature of 1160°C, 1200°C and 1240°C in a tube furnace. The microstructure of the Ti alloy foams were observed by Scanning Electron Microscope (SEM). It was revealed that the porosity content in the Ti foam was in the range of 16% to 31% and density in the range of 1.5 g/cm3 to 2.6 g/cm3. Moreover, the pore size of the titanium alloy foam is in the range of 187μm to 303μm. Although the sintering temperatures were found incapable of promoting overall densification to the Ti alloy foam, 1200°C was denoted to be the maximal temperature for promoting maximal porosity to the Ti alloy foam. Nonetheless, KBr was proven to be suitable as space holder for Ti foam preparation as referred to its stability and insolubility in the Ti alloy.
Influence of Calcination on the Properties of La0.6Sr0.4Co0.2Fe0.8O3-δ-Samarium Doped Ceria Carbonate
Authors: Rahman Hamimah Abdul , Muchtar Andanastuti , Muhamad Norhamidi , Abdullah Huda
Published: December 2013

The correlation between calcination temperature and properties (physical and electrochemical) of composite cathodes comprising lanthanum strontium cobaltite ferrite (LSCF) with samarium-doped ceria carbonate (SDCC) has been investigated. LSCF-SDC carbonate (LSCF-SDCC) composite cathode powders prepared via ball-milling were calcined at various temperatures in the range of 700850 °C. X-ray diffraction (XRD) results confirmed that the applied calcination temperatures do not affect the chemical compatibility and the LSCF perovskite cubic structure of the composite powders. FTIR spectra verified the presence of carbonates in the composite powders after calcination. The increment of the calcination temperature reduced the surface area of the particle from 10.9 m2/g to 6.5 m2/g. The electrochemical results revealed that the resistance of LSCF-SDC carbonate composite cathodes is dominated by the oxygen surface exchange reaction at the electrode surface. 750 °C was identified as the most appropriate calcination temperature for the LSCF-SDC carbonate powder when the cathode electrode showed the lowest resistance with conductivity value of 0.95 x 10-3 Scm-1. The findings are of potential relevance to utilizing the LSCF-SDC carbonate cathodes for low temperature solid oxide fuel cells (LT-SOFC).
Examination of CPT-Based Liquefaction Evaluation Methods for New Zealand Earthquake
Authors: Chen Tong Zhi , Yuan Xiao Ming
Published: December 2013

On February 22, 2011 a MW6.2 earthquake struck Christchurch in New Zealand, which is the first time that liquefaction acts as the main cause of damage since there is survey record of historical earthquakes. On the basis of field investigation and in-situ test data, domestic and foreign liquefaction evaluation methods based on CPT including Chinese code, Robertson and Olsen methods are examined and their applicability and reliability are assessed. Analysis shows that the method adopted in Chinese code is more dangerous, whose success rates of liquefaction and non-liquefaction evaluation are 70% and 94%.The other two methods abroad are severely conservative, for the success rates of liquefaction and non-liquefaction evaluation of Robertson method are 100% and 40%, and Olsen method 100% and 11% respectively. Liquefaction evaluation methods need further research to be improved.
Analysis on the Space Characteristics of Shanxi Private Gardens in Ming and Qing Dynasties
Authors: Liang Yi , Gao Jing
Published: December 2013

Shanxi Gardens play an important role in Chinese ancient gardens. This thesis aims to explore the development and space characteristics of the private gardens in Shanxi, analyze the factors behind the characteristics and call for the protection and study of the ancient gardens in Shanxi Province.
Effects of Wind Load on Hydrodynamic Performance of an Offshore Wind Turbine Semi-Submersible Platform
Authors: Xie Jia Rong , Zhao Cheng Bi , Chen Xiao Ming , Tang You Hong , Lin Wei
Published: December 2013

With the wind turbine become larger due to technology development, the effects of wind load on the dynamic behaviors of wind turbine system play a more important pole, especially for offshore wind turbine system with floating platform. To research such effects, the dynamic behaviors of a new semi-submersible platform of a 10 MW wind turbine in 300 m deep seawater are studied in this study. Firstly, frequency domain analysis is done to show the performances of the semi-submersible platform and prepare hydrodynamic coefficients for time domain analysis. Then time domain analysis is studied with the consideration of the coupled load effects of the wind turbine floating platform, mooring lines and ocean environment. Main load components on the wind turbine floating platform are disposed, and the effects of wind load are studied as a key point. Though the result shows that wave load still dominates the contribution to motions of rolling, heaving and surging, the contribution of wind load becomes more important than current load in the operation case, which is different of traditional floating platform.
Analysis of Shanxi Traditional Local-Style Dwellings
Authors: Tian Fang , Wang Jin Ping
Published: December 2013

Chinese traditional local-style dwelling houses are diverse, Shanxi traditional residents as an indispensable part of the residential buildings in China, stand out by its rich type and unique local characteristics. It is affected by inherent geographical environment, the political and economic, history and culture and customs, and many other factors, makes the Shanxi resident buildings are unique in architectural layout, space composition, plastic arts and sculpture art, gradually, and then form its own architectural style and features.
Mechanism of Micro-Void Initiation in Composite Materials during VaRTM Process According to the Pressure and Thickness of the Impurity
Authors: Kim Yun Hae , Kim Han Vin , Yoon Sung Won , Choi Byeong Geun , Lee Jin Woo , Choi Hyeung Sik , Ha Jin Cheol
Published: December 2013

The purpose of this study is the evaluation about the Micro-void generated by the impurity. The glass fiber reinforced composite made through the vacuum bag molding method was used with the impurity. The basalt fiber known as environment-friendly fiber was used as the fiber of the Micro-void specimen and the epoxy resin was used as the base material. The VaRTM process was performed for the making specimens. The change was given to the thickness of the impurity and pressure in order to see about production of the void. Consequently, as the thickness of the foreign material became thick and the pressure was enhanced, the size of the void grew and the production frequency of the void was enhanced.
Non-Linear Modeling of Single-Walled Carbon Nanotubes
Authors: Chwał Małgorzata
Published: December 2013

The present paper deals with the numerical evaluation of the effective Young's modulus values for the single-walled carbon nanotubes. The analysis is focused on the definition of the interatomic interactions applying the linear and non-linear numerical procedures and their influence on the results. The interatomic potentials, the continuum mechanics, and the finite element method are used in the conducted study. The non-linear numerical procedure revealed the variation of Young's modulus values for the carbon nanotubes during deformation.
Oscillation Suppression in a Delay-Coupled Flexible-Joint System
Authors: Jiang Shan Ying
Published: December 2013

A delay-coupled flexible-joint system is investigated in this paper. Because of the different time scales, the flexible-joint system could be transformed into a fast subsystem and a slow subsystem. The geometric singular perturbation method is used to obtain the slow manifold defining as the equilibrium of the fast subsystem. The eigenvalue analysis of the fast subsystem reveals a relation between the stability of the slow manifold and the time delay. The analysis results provide an idea of suppressing the small amplitude periodic oscillation via adjusting the time delay. Numerical simulations are performed to display the effectiveness of this method.
Linear Rock Cutting with SMART*CUT Picks
Authors: Shao Wen , Li Xing Sheng , Sun Yong , Huang Han
Published: December 2013

The short life due to heavy wear is a bottleneck that limits the usage of mechanical excavators for hard rock cutting. Thermally stable diamond composite (TSDC) tipped cutting tools have the main advantages of good thermal stability, high wear resistance and ability to mine harder deposit compared to the conventional tungsten carbide (WC) tipped cutting tools. Super Material Abrasive Resistant Tool (SMART*CUT) based on TSDC tip has been developed by CSIRO to improve the effectiveness of cutting tools when dealing with hard deposit in mining and civil industries. In this study, the effects of attack angle and depth of cut on the cutting performance of SMART*CUT picks in different cutting orientations were investigated. A tri-axial dynamometer and a data acquisition system were used to measure the cutter forces. Normal force, cutting force and resultant angle were correlated with depth of cut and attack angle. Cutting performances were compared in different cutting orientations. The results would be beneficial to the selection of mechanical excavator motor and the optimization of cutting drum design to some extent.
Coating of Fe-Mn-Si Shape Memory Materials on AISI 304 Stainless Steel by Laser Cladding Method
Authors: Xu Peng , Ju Heng , Lin Cheng Xin , Zhou Chao Yu
Published: December 2013

Using laser cladding method, the coating of Fe-Mn-Si shape memory materials (SMM) was prepared on the surface of AISI 304 stainless steel. The microstructure and microhardness of SMM laser cladding coating were measured by using a metallographic microscope and a scanning electron microscope, respectively. The phase composition was determined by X-ray diffraction. The wear resistance was evaluated on a high speed reciprocating friction tester. The results show that microhardness of the SMM coating is about Hv263, higher than that of the substrate (Hv225); the SMM coating is composed of ε-martensite and γ-austenite phases; the average friction coefficient of the substrate and SMM coating is about 0.85 and 0.71; the SMM laser cladding coating is of excellent wear resistance validated by friction coefficient, worn-out appearance and wear loss.
Effect of Annealing on Properties of the TiN & TiAlN Coatings Deposited on Powder Metallurgy High Speed Steel ( S790 )
Authors: Cao Chuan Liang , Zhang Xiang Lin , Dong Chun Fa , Zha Xiang
Published: December 2013

To improve the mechanical properties of the physical vapor deposition (PVD) coatings deposited on fine-blanking tools and increase the tool life, TiN and TiAlN coatings were deposited on the powder metallurgy high speed steel S790 substrates by Multi-arc ion plating, and then annealed at the temperature of 500°C for one hour in vacuum enviroment. The phase variation, residual stress, morphology, surface microhardness and adhesion strength of coatings were respectively analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Vickers hardness tester and automatic scratch tester. The preferred orientations in the coatings are not changed after annealing, indicating no disparities in the crystal structure of the coatings. The residual stress of coatings released a little after annealing, however the adhesion strength between the coatings and substrates increased obviously, which indicated that the properties of the TiN and TiAlN coatings deposited on S790 steel were improved.
The Sinusoidal Buckling Mechanical Analysis for the Coiled Tubing Based on Energy Method
Authors: He Chun Sheng , Liu Ju Bao , Yue Qian Bei , Wang Yan
Published: December 2013

Columns are prone to sinusoidal buckling and repeated instability on the effect of drilling pressure and fluid pressure during drilling operation. The resulted large area of random contact to borehole wall would affect the drilling efficiency. It made the backreaming and loading hard and the drilling pressure low. Using energy method, taking flexural deformation energy and external potential energy of strings, hole section (slant hole, bending hole, level hole) and annular clearance etc. into consideration, derived the counting function of force that sinusoidal buckling occurred on coiled tubing when it contact with the wellbore, establishing the mechanical analysis method of calculating for sinusoidal buckling of slim lined construction roof bolt and string borehole. It proves an effective method for the applying of coiled tubing drilling pressure and the optimization of process parameters.
The U-Bending Forming of Aluminum Foam Sandwich Panels
Authors: Chen Sheng Gui , Chen Hai Bin , Sun Zhen Zhong , Li Rong Yong , He Wei Feng , Zou Shun Qiang
Published: December 2013

The U-bending process of aluminum foam sandwich (AFS) is investigated, and a punch bending test is carried out in this paper. We discussed the bending deformation mode and generated the load & stroke curve of AFS panel by experiments. Macroscopic and microscopic punch forming mechanisms of AFS panels are analyzed by testing experiments and plasticity theory. We study the major deformation defects of AFS forming such as the delamination between the panel and the foam core, the excessive thinning of panels in the round corner, and shear stress cracks of the foam core. A conclusion is drawn on the panels variable blank holder force (VBHF) and the striking block control on the round corner, which would promote the forming technology of AFS.
Composition - Property Relationships of Magnetic Inks for Screen Printing
Authors: Zhang Yin Long , Jiang Wei , Lin Long
Published: December 2013

Magnetic cards are widely used as credit cards, gift cards and VIP cards. In many industries, the principal method for producing the magnetic stripe still employs magnetic tapes. Therefore, if magnetic inks could be printed directly on the poly (vinyl chloride) (PVC) cards, then there would be the potential to improve industrial efficiency significantly. In order to apply the magnetic inks to the credit cards or other PVC cards, the Screen printing technique was chosen as a suitable printing method.In formulation 19, it is easy to mix and disperse the iron oxide powders in binder, few agglomerates and agglomerates occurred in the dispersion and also the film thickness of this formulation is around 20 microns which is ideal for the magnetic stripe.
Research on Cost Risk Identification of Metallurgical EPC Project
Authors: Yin Zhi Guo , Li Hui Min
Published: December 2013

This paper describes the current status of our EPC projects in China, noting metallurgical EPC projects as complex process, long construction period, the use of fixed-price contracts, and other features make it faces huge cost risk, so it is necessary to conduct a cost risk management, while the metallurgical EPC project risk identification is the basis for subsequent risk management. Then, the specific metallurgical EPC project for the case describe in detail the methodology and process of cost risk identification, and ultimately the formation of risk breakdown structure table.
Research on Geometry Model and Stress State Leading-In through Heavy Rail Cooling to Compound Straightening
Authors: Song Hua , Yao Jin Kai , Li Kui Xing , Lian Fa Bo , Tong Shan Hu , Jia Hao , Yuan Si Yu , Wang Zhong Qiang
Published: December 2013

The hot preflex cooling and compound straightening are the last two consecutive deformation processes and determine the straightness, residual stress and cross-sectional size for fabricating hundred-meter heavy rail products. The compound straightening process needs to be adjusted by the preflex cooling status. For studying the straightness, residual stress and cross-sectional size of heavy rail products, the preflex cooling model (including the residual stress) of heavy rail after cooling should be taken as straightening model for studying the compound straightening. In this paper, the results by ANSYS implicit analysis (geometry model and stress state of the cold heavy rail) is fully imported to the compound straightening by ANSYS/LS-DYNA explicit analysis through an implicit-explicit conversion method, which resolved the connection problem of coupling and analysis models for solving complex models in multi-physical fields. It is very significant for solving the similar problems in engineering.
Dynamic Response Analysis of Square Honeycomb Sandwich Plates Subjected to Blast Loading
Authors: Deng Lei , Wang An Wen , Mao Liu Wei
Published: December 2013

The dynamic response of the square honeycomb sandwich plates subjected to blast loading was simulated and analyzed by using the finite element software ABAQUS.With the given mass per unit area,core sheet spacing and height,the optimal relative density of the core was obtained under blast loading of three levels.With this optimal relative density,the sandwich plates have the best shock resistance ability and the top and bottom face sheets have the smallest deflection subjected to impulsive load.The sandwich plates were compared with the solid plates having the same mass per unit area.The results show that the sandwich plates have higher strength and energy absorption capability.Furthermore,influence of geometrical parameters including core sheet spacing,thickness,height and face sheet thickness on the face sheetss maximum deflection were discussed.
The Simplified Flow Field Analysis Method of Multi-Layers Parallel Plates Perfusion Bioreactor
Authors: Gao Yu Bao , Zhou Wei Hong , Cen Lu Shan , Xu Yu Cong , Liang Jiu Xing , Luo Yu Xi
Published: December 2013

Multi-layers parallel plates perfusion bioreactor has the potential advantage in cells cultivation of tissue engineering and good scalability for cells cultivation on a large scale. It is necessary to analyze the distribution of flow shear stress (FSS) of bioreactors which has strong influence on the growth of cells. The result of meshing was not satisfactory because of the complexity of multi-layers parallel plates when using computational fluid dynamics (CFD) to analyze the FSS, and the amount of calculation was great and complex especially under the process of influence on FSS caused by analyzing the different structure. The new method of simplified flow field analysis was presented in this paper, which was based on relation between FSS and flow and made the process simpler by analyzing distribution of rate instead of FSS. The simulation result showed that this method can satisfy the requirement of precision and provide reference for the analysis of the flow field which had the established relationship between structural parameters and laminar flow within it.
Analysis of Plastic Strain between Substrate and Micro-Cantilever under Different Deformation Characteristics
Authors: Gao Hui Kai , Huang Jian Meng
Published: December 2013

The contact between substrate and micro-cantilever simplified as an ideal flat substrate contact with a micro-cantilever rough surface. A three-dimensional adhesive contact model was established on isotropic rough surfaces exhibiting fractal behavior, and the equivalent plastic strain was discussed using the finite element analysis. The maximum equivalent plastic strain and its depth were presented with the different paths of rough solid when loading. The result show that the equivalent plastic strain versus different depth which at different locations showed different laws, in the top area of the asperities versus different depth, the maximum equivalent plastic strain occurs in the subsurface range about 0.5μm from the surface or on the surface. In addition, with different deformation characteristics, the degree of the equivalent plastic strain was different.. The contact model between micro-cantilever rough surface and flat substrate will lay a foundation to further research on the substance of the process of friction and wear.
Supersonic Bi-Directional Flying Wing Wave Drag Optimization Based on Alternative Form of CST Method
Authors: Guan Xiaohui
Published: December 2013

Bi-directional Flying Wing (BFW) is a new supersonic civil transport shape concept that aims to meet the conflict requirements of high speed cruise and low speed take-off/landing missions. In this paper the Class-Shape-Transformation (CST) shape parameterization method is modified to represent the BFW shape, and new basis functions suitable for the BFW airfoil representation are constructed. The Far-field Composite Element (FCE) wave drag optimization is performed on both the flat bottom and symmetric BFW configurations, and the drag reduction effects and result precision are surveyed. It is suggested that significant wave drag reduction can be achieved by the FCE optimization for both the flat bottom and the symmetric BFW configurations. The wave drag coefficients with sufficient precision can be obtained in the FCE optimization of the symmetric configuration; while the FCE optimization results of the flat bottom one are not accurate enough.
Suppression of Vortex Shedding of Circular Cylinder by a Small Control Rod
Authors: Hsu Li-Chieh , Lai De-Chang , Ye Jian-Zhi
Published: December 2013

The physical phenomena of vortex suppression and flow patterns by deploying a very mall control cylinder in the near wake region of a main cylinder in low Reynolds numbers is studied numerically. The control diameter effect on vortex suppression and three flow patterns has been studied. The results shows the control cylinder can reduce vortex shedding frequency and suppress shedding partially or completely dependent on the diameter of control cylinder and Reynolds number. The results of a cylinder with control and without control agree with experimental and numerical studies.
An Immersed Boundary Method for Compressible Flows with Complex Boundaries
Authors: Yang Jie , Wu Song Ping
Published: December 2013

An immersed boundary method based on the ghost-cell approach is presented in this paper. The compressible Navier-Stokes equations are discretized using a flux-splitting method for inviscid fluxes and second-order central-difference for the viscous components. High-order accuracy is achieved by using weighted essentially non-oscillatory (WENO) and Runge-Kutta schemes. Boundary conditions are reconstructed by a serial of linear interpolation and inverse distance weighting interpolation of flow variables in fluid domain. Two classic flow problems (flow over a circular cylinder, and a NACA 0012 airfoil) are simulated using the present immersed boundary method, and the predictions show good agreement with previous computational results.
A Study on Strength and Training Characteristics of Elite Female Skaters
Authors: Zhang Xiao Ming , Xia Jiao Yang
Published: December 2013

With methods of ISOMED isokinetic muscle testing system and live observation on Olympic preparation and mathematical statistics, this paper tries to measure and analyze the characteristics of elite female speed skaters knee and hip flexor-extensor muscle strength and training content, period and load for the whole year. The main conclusions are as follows: 1. Features of the skaters knee and hip muscle strength are fit in with the sport biomechanical law, and their fast strength and greatest strength are higher than those of female athletes in other national events. In high speed area, the strength of female athletes even achieves the same level of male ones. 2. The equilibrium and coordination of flexor-extensor and same name muscle group have both reached a high level, but they are lower than international recommended values. 3. The training load of strength throughout the year peaks at the whole phases of preparation 1and preparation 2, the early stages of competition 1 and preparation 3. The load of short distance athletes is larger than that of long distance athletes, but the general trend of both is same. 4. National elite female skaters excise more than before in small muscle group, greatest strength in high speed, continuous speed strength and strength endurance. 5. Based on a comparative analysis of the testing results between these skaters and other athletes, the training arrangement can meet the strength requirements of specific training and can also be the reference of training for other athletes.
Affect the Comfort of Pants Crotch Curve Analysis of the Factors
Authors: Zhang Zhuo , Qiao Li Ping
Published: December 2013

This paper discusses the impact of pants crotch bend comfort factor. From the structure of the aptamer of pants, trousers fabric scalability and style shape, technology and other aspects of analysis, and propose effective improvements pants crotch bend comfort measures.
Research on the Application of Green Air Conditioning in the Granary
Authors: Di Yu Hui , Jiang Chun Yang , Xu Zi Long
Published: December 2013

By describing the environmental requirements for food storage, puts forward the green air conditioning system to create a low-temperature environment for food of these creatures such as ice storage air-conditioning, ground source heat pumps, solar cooling and so on. Combined the related system diagram or schematic in the context of promoting green and healthy, pointed out the future direction of development of the low-temperature grain storage.
Performance Comparison for Different Material Quantum Dot Single Intermediate Band Solar Cells
Authors: Wei Wen Sheng , Shan Feng , Zhao Shao Yun , Zhang Qiu Bo
Published: December 2013

Short circuit current density (Jsc) and photoelectric conversion efficiency (η) of the different material quantum dot intermediate band solar cells (QD-IBSCs) under full concentrated sunlight were compared in this work. The QD-IBSCs were designed with QDs formed from different excitonic Bohr radius semiconductors embedding in the different wide band gap materials. Modulation doping was used to realize partially filling the IB with electrons in QD, the influence of localized states from doping on IB was also considered. The performance of these SCs was numerically simulated based on the detailed balance principle. TheJscandηin QD-IBSCs can be adjusted via tuning the position and density of states of IB due to varying the mean size (d) and doping level of QDs in absorption region. Under the same doping level in an identical host gap material withΔEG=2.0 eV, theJscandηof the Si QD-IBSCs can be optimized with 4.3 nm-QDs, however, those of CdTe devices raises while those of Ge cells drops with increasing the sizes of QD from 2 nm to 8 nm. With changing the host gapΔEG, variation of the IB energy levelEHwith respect to valence band corresponding to the maximumηmwas explored, dependence ofηon the operation voltage was analyzed, and the impurity effect on theηwas taken into account. Present work indicates that an appropriate band gap material should be adopted to fabricate QDs to embed in suitable doped host gap one to obtain the high performance QD-IBSC.
Application of Axial Force Compensation for Steel Support System in Practical Project
Authors: Zhang Shi Min , Jia Xing Ming , Yuan Teng Kun , Liu Wei Guo , Jun Yin
Published: December 2013

The problem always exist in foundation pit engineering that the support axial force can not be regulated in the pit system in real time.According to setting the axial force compensation system,the problem would be solved perfectly and efficiently,realizing the fact control and adjust the support axial force and stability. The axial force compensation system which is constituted by jacks distributed in the pit has been confirmed the significant role to control foundation pit deformation and internal force monitoring combined with practical engineering