bluuebunny/crossref_metadata_2025 huggingface dataset:
Modal Analysis of Arrow Shaped Shovel Based on ANSYS Workbench
Authors: Chu Xu Hong , Wang Jun Fa , Jiao Ren Bao , Wu Hai Yang , Zhou Li Fei
Published: August 2013

In order to optimize the kinetic parameters of arrow shaped shovel, the paper carried on the modal analysis and the 3D graph was drawing by the application of Pro/E software. The finite element model was established by using ANSYS Workbench. After the constraint processing, the first six model shapes of the rack were obtained through the modal analysis of arrow shaped shovel. Based on the modal analysis, it can be found that the first six natural frequencies enlarge with the increase of the order, and the odd order of principal modes are horizontal hunting along shovel handle on both sides, the even orders are up and down perpendicular to horizontal direction. The maximum deformation of the first six model of the rack occurs at shovel head. The results present a theoretical reference for improving and optimizing the shovel.
Shear Displacement Method of Grouted Pile
Authors: Ye Jian Liang , Chen Shi Cai , Bao Liu Qing
Published: August 2013

Shear displacement method is used to predict the settlement of the grouted pile in this paper. An empirical relationship is used to determine the improvement of shear modulus for the soil around the grouted pile. A parameter is also proposed to represent the improvement of the shear modulus for the grouted soil at the pile tip. Shear displacement method is modified to consider the influence of grouting. The detailed calculation process of the method is described and determine of the parameter is also given in the paper.
The Genesis of Layer-Bound Polygonal Faults in the Sanzhao Sag of Songliao Basin
Authors: Ping Gui Dong , Fu Xiao Fei , Xie Zhao Han
Published: August 2013

Through new 3-D seismic data and the technique of coherent slice, the development characteristic of layer-bound polygonal faults (PFs) is summarized in Zhaozhou oilfield in the south of Sanzhao sag, Songliao Basin. the layer-bound faults that show preferential alignment have lengths of 1503000 m, throws of 510 m, most strikes parallel to the slope direction and aligned faults are antithetic to the bedding dip. PFs activity coincided with a late K2qn to early K2y stage tilting event, gravity sliding model is proposed as a possible mechanism for the deformation.
Fault Diagnoses Technology of Broken-Blade Propeller Induced Shaft Vibration
Authors: Ou Li Jian , Li Jun , Li De Yu
Published: August 2013

The broken-blade propeller induced centrifugal force and hydrodynamic lateral component force will cause the whirling vibration of the shaft system while one of the propeller blades breaks at different positions. Such whirling vibration is investigated in this paper, and the time domain waveform is obtained through using the finite element method. The frequency domain vibration is then calculated by applying Fourier transformation on its time domain waveform. According to the respond results of both time domain and frequency domain, the fault diagnoses technology of shaft vibration is proposed.
Multi-Sensor Multi-Target Data Association Algorithm Based on Swarm Intelligence
Authors: Yuan De Ping , Zheng Juan Yi , Shi Hao Shan
Published: August 2013

An swarm intelligence algorithm, particle swarm optimization (PSO) algorithm, is used in data association problem for multi-sensor multi-target data association. The association relation between measurements and targets is described by the likelihood function of filter innovation to establish the model of the optimal combination. Lagrange relaxation technology is used to reduce the combination to two dimensions firstly when solving the optimal combination problem, and then the improved PSO algorithm, which based on the cross and mutation rules, is used to obtain the optimal solution, and get the optimal association pairs for measurements and targets. The simulation shows the superiority of the method in accuracy and speed at last.
Open Service Robot Development Platform
Authors: Ma Xi Pei , Qian Bing Feng , Wu Ting
Published: August 2013

Due to the urgent requirements of the current domestic robots development and technical talents, this paper has proposed a methodology on service robot development platform, which is used to achieve the target of basic teaching and stimulate students' creativity. The development platform is composed of mechanical structure, hardware and software control systems. The advantages of the platform are modular, openly designed and easily restructured. So, the robot technology can be developed on the platform. The platform integrates machinery, electronics, communications, computer technology etc. Especially, the control software adopts 3D simulation technology besides network management and remote control functions. It is well-known that Single-arm robot is representative in the development platform. This robot is taken for examples of the mechanical structure, control systems and software design methods during the development platform. The results have been proved that the development platform is beneficial to improve students' practical abilities, help employment and highlight advanced studies.
Design and Implementation of a Large-Scale Gravity Compensation System for Lunar Rover
Authors: Liu Zhen , Gao Hai Bo , Deng Zong Quan
Published: August 2013

This article presents knowledge on the design of a large-scale Gravity Compensation System (GCS) for lunar rover. The system comprises a large-scale planar position servo system that covers an area of 900 square meters and a force servo system that generates compensation force. The major problems in system design are clearly identified so that the mechanisms and control strategies of the GCS could be better understood. Experiment results are also included to extend the knowledge on this system.
Robust Control of Modular Gun Propellant Select Mechanism with Unknown Dead-Zone
Authors: Zou Quan , Chen Long Miao , Qian Lin Fang
Published: August 2013

Modular gun propellant select mechanism is an important subsystem of the gun automatic loading system, it is used to select desired amount of modular gun propellants, which are placed in a receptacle. The distance between two adjacent propellants is short because of the small storage space, so robust precision control is important and necessary to reliably select the desired amount of propellants. The mathematical model is obtained, and nonlinear characteristics such as nonlinear friction, transmission clearance, and unknown dead-zone and so on are also considered. To simplify the problem, a simplified disturbing force model is used to replace the impulse force when the propellant, which is fastened by a hook, is freed. Considering that the system parameters are time-varying and also the system is influenced by an additional disturbance, a fuzzy sliding mode controller is designed by using the sliding mode control theory and fuzzy control theory together, the sliding mode control forces the system to move along the desired trajectory while the fuzzy control is used to reduce the chattering. Three situations, that are select one, three and five propellants respectively, have been studied, simulation results show that the presented fuzzy sliding mode controller is not only insensitive to the system parameters change and the additional disturbances, but also has high position precision.
Intelligence Predictive Control Study on Lime Rotary Kiln Temperature
Authors: Zhang Li , Wang Song , Su Guo Jun
Published: August 2013

For the non-linearity, large time lag characters of rotary kiln, we use intelligent predictive control method to control it. The prediction model, scrolling optimization and feedback adjustment are ultimate constituted the predictive control system each part. Gas flow measurement is used to realize rotary kiln`s temperature predictive control,and took NN-Model as prediction model to realize the intelligent forecast. The results of simulation show that this method has better stability and robustness than the traditional control method.
The Automatic Control System Based on PROFIBUS for the City Sewage Treatment
Authors: Huang Xiao Ping , Qing Qi Xing
Published: August 2013

On the basis of the computerized technological process control of sewage treatment in a urban sewage treatment plant in the Zone of Nanning, the author had brought forward a plan of PROFIBUS that based on automatic control system for sewage treatment, and designed the automatic control system diagram and the PROFIBUS network diagram for sewage treatment plant. At the same time, the author also made a study of techniques to control the sewage aeration, which was the most difficult problem in sewage treatment process. The fuzzy controller could indicate the changes of the water quality in treated sewage, effectively controlled the volume of aeration and then cut down the operation costs,it had produced good economic and social benefits.
Two Synchronization Schemes for Chen Chaotic System
Authors: She Xin Ping
Published: August 2013

This paper presents two novel synchronization schemes for Chen chaotic system, drive-response synchronization and adaptive synchronization with unknown parameters, numerical simulation results demonstrate the effectiveness of the proposed method.
Prediction of Insulator's Equivalent Salt Deposit Density in Power System
Authors: Ai Li , Cheng Jia Tang
Published: August 2013

The equivalent salt deposit density (ESDD) of insulator in power system is the main basis of defining pollution classes and mapping pollution areas. However, The meteorological factors on it is complex, using traditional methods is difficult to establish accurate mathematical model to express the relationship, In this paper, the gray theory and neural network model to reflect the changing trend of data series on the apparent effect, Gray neural network model used to predict the insulators ESDD under certain meteorological factors, and to design a neural network compensator correction on the predicted results. The simulation results show that the model has higher prediction accuracy, better than a simple gray neural network model, and have certain theoretical value and practical application value.
Dynamic Modeling on Smart Flexible Beam with Large Overall Planar Motion
Authors: Zhang Juan , Shu Ya Feng , Bai Bin
Published: August 2013

A simplified smart flexible spatial piezoelectric beam with overall motions is studied in this paper. Considering the geometrically nonlinear effect resulting from curved and twisted deformations, and considering the kinetic energy of the piezoelectric actuator and the coupled terms of deformations in the longitudinal, lateral and transversal directions, and taking into account the coupling of electric performance of piezoelectric material and structure deformation, finally, the Rigid-flexible-electric coupling dynamic model of piezoelectric smart beam is established by infinite element method and Lagrange equation.
The Research on a General Dynamic Model for Torsional Vibration for Disc-Type Rod Fastening Rotor Systems
Authors: Gao Si Xiao , Wang Ai Lun , Su Yong Lei
Published: August 2013

In the paper,considered the contact effect between the disks interface,a number of dynamic model for torsional vibration for disc-type rod fastening rotor systems are established to find the rule of establishing them.And then a general dynamic model is put forward ,which can describe the torsional vibration for disc-type rod fastening rotor systems.The model which can be used generally simplifies the modeling process and get the torsional vibration characteristics quickly.Then we have calculated and tested torsional vibration characteristics of an experimental rod fastening rotor and compare the difference between theoretical calculation result and test result.The result shows that the dynamic model established by this paper is valid.
Analysis of Nonlinear Local Buckling of Crane Telescopic Boom
Authors: Huang Xin Lei , Ji Ai Min
Published: August 2013

The problems of nonlinear local buckling of telescopic boom of truck crane in the practical working condition were studied. The arc-length method of nonlinear buckling analysis was introduced. And the corresponding solving steps were given. Based on ANSYS software and redevelopment of ANSYS with APDL (ANSYS Parametric Design Language), the solution of critical stress of nonlinear local buckling of the boom was obtained. The critical stress values of the linear buckling and those of the nonlinear buckling of the boom were compared. The influence of different initial imperfection on the critical stresses of nonlinear local buckling of the rectangular, hexagonal and dodecagonal sectional boom was analyzed. The results indicate that the presented method can solve the problems of the nonlinear local buckling of telescopic boom of truck crane effectively.
The Study of Mechanical Seal Leakage Detection System
Authors: Sun Ze Gang , Yang Chang Niu , Chen Lei
Published: August 2013

The mechanical seal bench is the test platform for the leakage of the mechanical seal.The mechanical sealing leaking are closely related to the fluid pressure and temperature.The control system of the fluid pressure and temperature be designed to meet the needs of mechanical seals working in defferent conditions and the system of the leakage data acquisition and processing are designed based on C51 and C++BUILDER. The data collected be output on curve fitting.The test stand is certain guiding significance for the design and testing of the mechanical seal.
Flotation of a Lead Sulphide Ore in Sichuan, China
Authors: Liu Si Qing , Li Xiu Juan , Wang Wan Ping , Zhang Min
Published: August 2013

A lead sulphide ore sample containing 4.64%Pb, 17.38g/t Ag was subjected to this experimental study and taken from a mine in Sichuan province, China. In this study, the effects of different parameters such as optimum mesh of grind, selection of collectors and modifiers, dosages of the reagents, flotation flowsheet were investigated and developed. A lead concentrate assaying 57.77% Pb and 205.6 g/t Ag can be obtained at the recovery of 93.37% and 88.72%, respectively, by applying two roughing, one cleaning and one scavenging operations. The dosages of the reagents in first roughing stage are 500g/t sodium silicate, 150g/t BuX (Butyl xanthate) and 45g/t terpineol, while these in second roughing and scavenging operations are half and quarter of the above.
Simulation of Solar Organic Rankine Cycle System Using Turbocharger with Cycle Tempo and Environmentally Friendly Fluid
Authors: Nutranta Ruli , Al Hamid Idrus , Nasruddin  , Harinaldi B.
Published: August 2013

Organic Rankine cycle (ORC) is a modified rankine cycle with working fluids, of organic material (Refrigerant). Refrigerant pentane has low boiling point, therefore ORC can be used in power plant which uses low temperature resources, such as solar thermal exhausted gases and geothermal wells. Organic Rankine Cycle (ORC) is used to convert heat energy into mechanical energy or electricity generated by a low temperature of the hot sun. The working fluid used is HCR12, HCR22, HCR134a and Pentane. Simulations performed with an organic Rankine cycle temperature and pressure with cycle tempo program. By programming the simulation cycle tempo and got the result on the maximum power a turbine to the conditions of the working fluid Pentane to the input turbine T = 700C and pressure = 2 bar can generate 2.07 kW. Turbocharger is one of the alternatives in the energy conversion of the energy of motion into electrical energy. Turbocharger rotation will be used to turn a generator and converts the energy of motion into electrical energy.
The Role of Exhaust Gas Recirculation in Flameless Combustion
Authors: Hosseini Seyed Ehsan , Wahid Mazlan  A. , Abuelnuor Abuelnuor Abdeen Ali
Published: August 2013

Recently, flameless combustion has been developed as an innovative combustion method to intensify combustion performance and to decrease the pollutant formation contemporaneously. The outstanding economic aspects and merits of flameless combustion have persuaded the combustion scientists to investigate about this unique technology in the various ways and conditions. In flameless chambers the roles of heat and mass transfer are more highlighted than traditional combustion due to Exhaust Gas Recirculation (EGR) method. Flameless systems are characterized by highly preheated combustion air and burned gases recirculation before reaction. This paper is concerned with the detailed theoretical analysis of thermodynamics relationships in flameless combustion method.
Performance of Thermoelectrics and Heat Pipes Refrigerator
Authors: Sungkar Ali A. , Ikhsan Firman , Afin Faisol M. , Putra Nandy
Published: August 2013

Most of refrigerators commonly use the conventional refrigeration system known as Vapor Compression Refrigeration System becoming a big issue lately due to ozone depleting substance it uses as the refrigerant. This paper will shows step by step of an experiment with the objective of constructing a refrigeration system based on thermoelectric which is reliable and compete able with the Vapor Compression Refrigeration System. The designing of this refrigeration system shows attention to the environment that is combined with the knowledge so the environmental friendly technology can be applied. The performance of thermoelectric refrigerator was conducted under variation of input power (40W, 72W, and 120W) and operated in ambient temperature and cooling load of water 1000mL to investigate the characteristic of system, the performance, and also the COP. The COP is decrease by increasing of cooling load, QL. The best actual COP is 0.182 reached when the refrigerator operated at input power 40W. The result, it shows that decreasing of ambient temperature affects the decreasing of cabin temperature. Thermoelectric and heat pipe refrigerator cooling system can reach cabin temperature with power 120Watt (8.73A, 14V) produces temperature of compartment is 10.63°C indicates effective performance work-based thermoelectric applications.
Investigation of the Velocity Profiles in a Ninety-Degree Curved Standing Wave Resonator with Particle Image Velocimetry
Authors: Mohd Ghazali Normah , Abd Rahim Irfan , Quenet Terry , Ab Muin Zaki
Published: August 2013

Travelling wave thermoacoustic heat engines have been reported to have a higher efficiency than the standing wave ones. The former are generally large systems which consist of toroidal shape resonators. While standing wave heat engines are inherently smaller, a reduction in size could be considered which may involve curvatures as compared to the straight tube conventional systems. However, as with the streaming losses in the travelling wave resonators, losses due to the curvature may be generated. This study involves preliminary experimental measurements using the Particle Image Velocimetry (PIV) method to analyze the velocity profiles in a standing wave resonator before and after a ninety degree curvature. This design can reduce the space generally occupied by the straight standing wave resonator. The overall length of the resonator fits a quarter wavelength wave based on the straight closed-end tube type. The working gas is air at 1 atmospheric pressure. Results have shown that the velocity profiles after the stack but before the curvature exhibit clear straight paths up just as reported elsewhere. Signs of disordered motion could be observed just before the bend and the pattern continues until after the curvature. The results are obtained before one periodic cycle and before the acoustic wave front hit the tube end. The trend is expected to affect the overall thermoacoustic performance of the engine as returning gas particles interact with the oncoming particles that pass by the curvature.
Evaluation of Residual Iron of Carbon Nanotubes Treated by Acid
Authors: Ling Xin Long , Zou Li Ming , Wei Yi Zhe , Xu Su
Published: August 2013

Multiwalled carbon nanotubes treated by hydrochloric acid treatment were in detail analysized by thermogravimetric analysis and SEM. The optimal technological conditions are that the concentration of the solution is 6 mol/L, the treating temperature is 90 °C, the treating time is 4 h and the mass ratio of solution to MWCNTs is 200:1. This result can also be verified by the contrast of SEM photographs of untreated and treated MWCNTs.
Research on Driveline Resistance of Micro-Automobile
Authors: Wang Feng , Mo Yi Min , Zhang Jie , Wang Jin Tao
Published: August 2013

This article describes a method, based on drum test and performance of drive axle test, to find the distribution of resistance itself and its relationship with speed in whole driveline and drive axle by processing data from the results of test. A related analysis equation can be found by analyzing the power consumption with different torque inputs.
Implementation of Particular Models of Innovative Servomechanisms
Authors: Moscatelli Davide
Published: August 2013

This paper describes a model based analysis of a differential planar servomechanism (two degrees of freedom); this system is meant to achieve high performance as regards the positioning precision (meant as both repeatability and accuracy) keeping a relative high dynamic.
A Review on Brønsted Acid Ionic Liquids Catalysts for Biodiesel Synthesis through Transesterification
Authors: Han Ben Yong , Li Tao , Deng Rong Qun , Xiong Xiang Feng , Chen Chao Yin
Published: August 2013

Biodiesel has attracted considerable interest in recent years as an alternative, biodegradable and nonpolluting transportation fuel. Conventional alkaline process for biodiesel production are energy consuming and generate undesirable by-products such as soaps, that make difficult the separation and purification of biodiesel. Ionic liquids as environmentally benign chemical solvent, had been used in diverse chemical reactions. Especially, they could be applied in biodiesel production. Preparation of biodiesel catalyzed by ionic liquids have many merits, such as no corrosion to equipment, no pollution to environment, and reusability. Ionic liquids can improve the catalytic activity and they have wide utilization prospect in biodiesel preparation. In this paper, the advances in the Brønsted ionic liquids catalysts and their application in biodiesel production through transesterification of oils and fats were reviewed. In addition, the prospect for the application of the ionic liquids to catalyze biodiesel production was also stated. Since the cost of ionic liquid may be an issue, there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.
Study on Motion Simulation Method of Parallel Mechanism Based on ADAMS
Authors: Wang Huan Gong , Wu Xiao Qing , Wang Li Ping , Kang Ning Min
Published: August 2013

This paper takes a parallel mechanism of a loading test device, analyzes a degree of freedom of the parallel mechanism, builds a geological model in ADAMS software, applies restriction and load, and sets a performance function; this paper solves the problem of Jacobian matrix ambiguity of the parallel mechanism through releasing three kinematic pairs in ADAMS, transforms the solved angle to Euler angle of coordinate series of two parts through local coordinate system of ADAMS, simulates and solves the included angle movement scale between following ground jack 5 and dynamic and static platforms through the performance function of ADAMS, thereby providing accordance for the design of the loading test device.
Research of the 3-DOF Helicopter System Based on Adaptive Inverse Control
Authors: Wang Xiu Yan , Wang Ying , Li Zong Shuai
Published: August 2013

For the flight control problem occurred in 3-DOF Helicopter System, reference adaptive inverse control scheme based on Fuzzy Neural Network model is designed. Firstly, fuzzy inference process of identifier and controller is achieved by using the network structure. Meanwhile, the neural network connection weights are used to express parameters of fuzzy inference. Then, back-propagation algorithm is adopted to amend the network connection weights in order to automatically identify the fuzzy model and adjust its membership functions and parameters, so that the actual system output of adaptive inverse controller control which is adjusted can track the reference model output. Finally, the simulation result of 3-DOF Helicopter System based on the scheme shows that the method is effective and feasible.
Simulation of the Discharge Path in Discharge Process from Thundercloud to Ground
Authors: Gan Zheng Ning
Published: August 2013

Based on fractal theory and WZ model of gas discharge, The spacial temporal behavior in discharge process from Thundercloud to Ground was simulated efficiently. Moreover, we discussed the probability index and the field intensity of the discharge path and their influence on the fractal dimension and the discharge path., and pointed out that the research should focus on the relation between the probability index and the fractal dimension.
Numerical Performance Study of Small Size Lifting-Body Reentry Vehicle
Authors: Rizvi S. Tauqeer ul Islam , He Lin Shu , Xu Da Jun
Published: August 2013

The multiphase numerical optimization study has been carried out for a 2-stage boost vehicle and small size X-33 type lifting-body reentry vehicle with heat rate and dynamic pressure constraint. The problem has been modeled as a nonlinear, multiphase optimal control problem with the objective to compute the optimum burn-out conditions as well as the best control deflections that would maximize the cross range performance of the boost-glide vehicle under study. The study has been performed using hp-adaptive Pseudospectral method. Comparative performance of the lifting-body vehicle with conventional ballistic missile trajectory has also been carried out. It has been found that for vehicle under study, and near maximum down range, the optimum burn-out angle is 13.6 degree which results in a cross-range of more than 100 km.
Experimental Study of a Mechanical Flapping Rotary Wing Model
Authors: Zhou Chao , Wu Jiang Hao , Guo Shi Jun
Published: August 2013

The effects of kinematic parameters (power input, rotational speed and initial angle of attack) of a newly proposed flapping rotary wing model on its averaged lifting force were studied experimentally. It was found that increasing the power input and wing initial angle of attack in a range (i.e. less than 15°) can increase averaged lifting force remarkably while rotational speed seems not to be a key variable determining the lift production. Besides, averaged lifting force could also be improved significantly and the wide range of initial angle of attack could be enlarged effectively to obtain higher averaged lifting force by wing structure selection properly. It was suggested that a proper selection of the wing structure, initial angle of attack (10° to 15°), and power input of the flapping rotary wing can be beneficial for a higher averaged lifting force production in the design of a micro air vehicle.
FE-Modal Approach to Model Geometric Nonlinearities of High Aspect Ratio Wing
Authors: Ahmad Kamran , Wu Zhi Gang , Hasham Hassan Junaid
Published: August 2013

Geometrical nonlinearity of high aspect ratio wing arises from the tip deflection which has been modeled through combined FE/modal approach. Generalized aerodynamics forces are obtained through commercial aeroelastic package. In time domain modeling, reduced frequency dependency of the aerodynamics need to be accounted. For state space time domain models this can be done through rational fraction approximation (RFA) of aerodynamics. Karpels minimum state approximation has been used in this work. Linear and nonlinear aeroservoelastic analyses of a high aspect ratio wing have been presented. Only stability and flutter issues are considered in this work while no external input has been considered.
A Numerical Simulation of Parachute Opening Process Based on ALE Method
Authors: Zhang Y. , Cheng H. , Yu L.
Published: August 2013

In this paper, the parachute opening process of finite mass situation was simulated based on ALE method. The results of structure change, the flow field change and some important aerodynamic data were obtained. Compared with the experiment, it can be found that the opening process was same with the actual opening. This method was useful in parachute designing and performance analyzing.
Uniaxial Mechanical Response of Polycrystalline Shape Memory Alloys
Authors: Babacan Nazim , Ozsoy Istemi Baris
Published: August 2013

Shape memory alloys (SMA) are materials that can remember their original shapes. Even if they are subjected to high deformations, they can return back to their original shapes when loading is removed. Their deformation mechanism is based on martensitic phase transformations (PT). In this study, uniaxial material response of polycrystalline SMA is inspected using finite element (FE) method. The material model developed by Levitas and Ozsoy (2009) is used and stress-strain diagrams and volume fractions of austenite and martensite during external loading are determined. The results are found to be in agreement with the experimental results. Moreover, increase in athermal friction, which prevents the interface propagation, delays the PT and for different friction values, different hysteresis is obtained. It is also shown that material response determined by experiments can be obtained using this model.
Study on Micro Mill-Grinding Technology
Authors: Wang Chao , Gong Ya Dong , Yin Guo Qiang , Wen Xue Long , Cheng Jun
Published: August 2013

Micro mechanical processing is the effective method for machining micro scale parts. Micro mill-grinding technology is presented based on micro milling and micro grinding processes. The machining principle of micro mill-grinding is studied, and compound tools for micro mill-grinding are fabricated based on spraying technology. Experiments are performed on Al 6061-T6 with the three-dimensional micro machining system. The results show that submicron surface roughness can be obtained by micro mill-grinding. Abrasive grains of mill-grinding tools fabricated by spraying method shed easily. Smaller abrasive particle size improves the surface quality and increases the tool life.
A Study on Performance Comparison of Integrated Aerodynamic-Ramp-Injector/ Gas-Portfire Flame Holder with Cavity
Authors: Wei Bao Xi , Gang Qiang , Zhang Yan , Liu Rong Jian , Tian Liang , Xu Xu
Published: August 2013

Experimental study of an integrated aerodynamic-ramp-injector /gas-portfire (aero-ramp/G-P) has been conducted in a hydrogen-fueled scramjet combustor. The aero-ramp injectors consisted of four flush-walled holes, arranged to induce vorticular motion and enhance mixing. For comparison, a recessed cavity with four low downstream-angled circular injector holes was also examined. The combustor models were investigated experimentally using the scramjet direct connected test facility at the Beihang University. The facility can deliver a continuous supersonic flow of Mach number 2 with a total temperature of 1200K. The hot experimental results showed that the combustion efficiency and air specific impulse of aero-ramp/G-P are 85% and 35s while the corresponding values of cavity are 92% and 34s. These results justify the feasibility of aero-ramp/G-P flame holder.
CFD Modeling and Simulation of Transesterification Reactions of Vegetable Oils with an Alcohol in Baffled Stirred Tank Reactors
Authors: Poley Isabela M. , Oliveira Leandro S.
Published: August 2013

Alcohol and triglycerides do not form a single phase mixture and thus there is a poor surface contact between them causing transesterification to proceed relatively slow. Introduction of stirring improves the surface contact and consequently the reaction rates and biodiesel yields. Thus, in industrial processes, transesterification is usually carried out in stirred tank reactors. Investigating how this type of reactor works is necessary for successful design, operation and optimization. Experimental methods for investigating flow-fields and chemical reactions are expensive and time demanding and cannot meet this challenge accurately. An alternate way is to model and simulate stirred tanks by computational fluid dynamics (CFD). Thus, in this work, a CFD simulation of transesterification was performed, with reaction rates being evaluated by solving a set of differential equations describing the reaction kinetics. The concentrations profiles for the expected components were in accordance with the kinetic model, and the mass fraction patterns showed efficient mixture.
Reduction Nitridation Synthesis of Bauxite Based β-SiAlON by Aluminum / Silicon Compound
Authors: Guo Yan Qin , Wang Yong Wei
Published: August 2013

Study of aluminum / silicon compound reduction nitridation synthesis of bauxite-based β -Sialon reaction process, using mass change ratio of the specimens and XRD, SEM, EDS analysis. The results were compared with the specimens separately using Al and Si reducing agent.The results show that:at 1100 only Al reacts with N2 and SiO2 to form AlN and Si; At 1200~1350°C, Si takes part in reduction-nitridation with subsequent formation of SiAlON；At 1450~1550°C，there is noticeable increase in β-SiAlON formation, the appropriate temperature is 1500°C.The amount of β-SiAlON formed is higher and crystale growth is better than that of single reducing agent.
Experimental Investigation of Temperature-Current Rise in Fine PCB Copper Traces on Polyimide, Aluminium and Ceramic (Al2O3) Substrates
Authors: Petrosyants Konstantin O. , Popov Anton A.
Published: August 2013

Three types of copper traces for PCBs were investigated: 1) 2.5 μm thin film lines (Ti;Cu;Ni) on aluminium and ceramic (Al2O3) substrates; 2) 2.5 μm thin film lines (Ti;Cu;Ni;Au) on ceramic (Al2O3) substrates; 3) 15 μm traces (Cu;Ni) on polyimide substrate for high density interconnection PCBs. The width of all types of traces was varying in the range of 100-500 μm. The set of temperature-current diagrams for different PCB scenarios are presented and analyzed. The temperature caused by Joule heating was measured using IR camera Flir A40 with macrolens. For different cases the current was set in the range of 0.1-3 A; the measured temperature was in the range of 20-140 °C. The close agreement between the results measured and simulated with ELCUT software tool was achieved.
Evaluation of Process Wear of Selected Tool Steels for Injection Molds
Authors: Greškovič František , Dulebová Ľudmila , Duleba Branislav , Sikora Janusz W.
Published: August 2013

The aim of this contribution is to test the suitability of selected types of tool steels used for manufacturing of injection molds. Experiments were realized by the simulation of adhesive wear using laboratory equipment Amsler, which allows the testing of grinding pairs. Evaluated grinding pairs consisted of tool steel and two types of roundels. Tested polymeric materials were based on pure PA6 and PBT filled with short glass fibers, prepared by mixing process in twin screw extruder. The wear of five types of tool steels were evaluated by weight decrease before and after the experiment, while changing the friction coefficient of grinding pairs, material of grinding pairs and sensing the roughness of steel before and after wear.
Study on the Influence of the Tailing Sand on the Performance of Pre-Mixed Mortar
Authors: Wang Ya Li , Lan Ming Zhang , Xu Hai Bo
Published: August 2013

Large applications of pre-mixed mortar and the dwindling natural sand resources make people feel anxiety about the sustainable development of pre-mixed mortar, therefore, it is imperative to find replacement of natural sand. In this paper, several kinds of local tailings are selected. First, the basic performances of tailing sand are analyzed, then, the effect of the tailing sand on the performances of pre-mixed mortar are tested. The tests show that the mortar performance meets the technical requirements absolutely when tailings are used as aggregate mix mortar. When tailings substitute the natural sand, the mortar has qualified consistency and hierarchical degrees, but the strength is slightly lower. The natural sands are added to the limestone with more content of limestone powder which enrich the aggregate gradation, decrease the porosity of the aggregate and increase the fluidity. Also, both the consistency and hierarchical degrees of the mortar are very good. The tailings can be partially or completely substituted for the natural sand to mix the mortar, therefore, the exploitable yield of the natural sand can be reduced. The tailings are very suitable for mixing mortar.
Study on a Structure of Manganese Oxide, Mn3O6(H2O)2
Authors: Liu Hai Xing , Guo Huan Mei , Ye Kai Qi , Xiao Jing Zhong , Zeng Guang
Published: August 2013

A manganese oxide, Mn3O6(H2O)2 has been synthesized from a hydrothermal reaction and the crystal structure has been determined by means of single-crystal X-ray diffraction. The Mn1 atom is coordinated by four O atoms. The Mn2 atom is coordinated by six O atoms. The molecular structure stabilized by the O-H...O hydrogen-bonding interactions.
Series Switching Power Supply with Wide Input Voltage Based on Dual-Loop Control
Authors: Xu Hong Mei , Jin Yong Gao
Published: August 2013

The circuit of series switching power supply based on voltage and current dual-loop control is proposed, which can work in the voltage range from 12V to 90V. It is less influence to working state when capacitive load is accessed. The circuit have the function of quickly response, short circuit protection and overcurrent protection. The power supply have advantages of low-cost and working stability, which can be used to different various industry alarms and blasting signal lights in the wide voltage range.
Heat Design and Temperature Characteristic Experiment of Fiber-Optic Gyroscope
Authors: Huang Ye Xu , Shi Zhong Ke
Published: August 2013

The interior thermal power consumption of fiber-optic gyro is calculated, According to the interior heat source distributing of fiber-optic gyro, the heat design project of fiber-optic gyro is given and designed two kinds different fiber coil framework. The two kind different fiber coils are simulated on heat exchange by ANSYS software. Contrast on the temperature characteristic of two kind different fiber coil gyro has been done by experiment. The simulation and experiment results show that the temperature characteristic is improved to this fiber-optic gyro with interlayer fiber coil framework, the bias stability of the fiber-optic gyro is improved with temperature variety, and the interlayer fiber coil design project is effective and validated.
A Computer Vision Measurement System for Linear Deformation of Line Heating
Authors: Xiang Zu Quan , Liu Zhi Hui
Published: August 2013

Line heating is an important technique for processing hyperboloidal outside plate of ship hull. To realize the automation of the line heating, the deformation rule in line heating should be researched. In this paper, the computer vision measurement technique is applied to find out the disciplinarian of linear deformation in line heating. The principle of computer vision measurement is firstly introduced in this paper. The emphases are the images collection, camera calibration, edge detection, and 3D data reconstruction. Then some key techniques for ensuring the measurement precision are presented. At last, the result of experiments is given. The experiments showed that the measurement system was valid for measuring the linear deformation of line heating.
Characterization and Preparation of Modified Coarse Wool by KMnO4
Authors: Zhang Hai Yan , Hu Xue Min
Published: August 2013

The surface modification process for coarse wool fiber which was oxidized by KMnO4 first, and then MnO2 covering on the fiber was reduced with Na2SO3 was studied. The method for surface modification of coarse wool fiber was determined from comparative analysis, the optimum oxidation process was as follows: concentration of KMnO4 at 3g/L, time 15min, temperature 50°C, ratio of water and wool fiber was 50:1, and the optimum reduction process: Na2SO3 concentration at 20g/L, time 8min, temperature 55°C, ratio of water and wool fiber was 50:1. Compared with original wool fiber,the breaking strength and fineness of modified coarse wool fiber decreased, while the moisture regain increased from 15% to 18%.
Inner Hole Diameter Measuring Based on Capacitive Sensor
Authors: Sun Xuan , Ma Yu Zhen , Yu Yong Xin , Zheng Yi Zhong
Published: August 2013

nner hole diameter measuring system based on capacitive sensor was introduced in this paper, the structure characteristic of coaxial cylindrical capacitive probe in measuring inner hole diameter was analyzed;aiming at the signal analysis and control for the whole measurement system, the equipotential guard ring technique was adopted to eliminate edge effect caused for the sensors effective measuring polar plate, the transform circuit with operational amplifier was adopted to overcome the nonlinear defects resulted from polar distance change, the driving cables technique was used to reduce the influence of parasitic capacitance;and then we realize the precision diameter measurement in holes any depth.
Analysis on Domestic Factoring Risk Identification Based on Bussiness Processing Technology
Authors: Cheng Guo Ping , Tang Di , Liu Bei Bei
Published: August 2013

Based on the study of basic risk identification method, this paper analyzes domestic factoring risk identification methods and puts forward the basic model based on business process of domestic factoring risk identification, then provides the new ideas for risk identification, the paper lays the foundation to domestic factoring risk evaluation and control system, so it is good to construct a complete, standard domestic factoring risk management system.
Research and Application of "Transition and Echo" in Molding Design of Farm Machineries
Authors: Chen Wei
Published: August 2013

The perfect moulding must have transition and echo, so "transition and echo" is the aesthetic principle that the moulding design of farm machineries have to observe. In some farm machinery products as an example,illustrates that the proper" transition" of products gives people lively, clever feeling, and has clear, certainly, soft beauty , and that reasonable " echo" of products gives people harmonious and unity feeling, and has friendly, movtion, open aesthetics characteristics.
Public Key Techniques for Prevention of Resource Exhaustion Attack in Wireless Sensor Networks
Authors: Heo Ju Seung , Ok Ki Sang , Kim Kee Cheon
Published: August 2013

This paper proposes a prevention mechanism for resource exhaustion attack in Wireless Sensor Networks (WSN). WSNs are widely used in science, medical, and military applications. However, WSN has problems of small memory, weak processors, and the limited battery power. On the other hands, public key techniques provide powerful security, but they need high energy, memory, computation cost than the symmetric cryptography. Therefore, we propose a more efficient protocol than the existing protocols in WSN, which analyze RSA algorithm and simulate ECC algorithm in CC2420 which is a true single-chip 2.4Ghz IEEE 802.15.4 compliant RF transceiver designed for low-power and low voltage wireless application. We also compared our proposed protocol and other public key-based protocols.
Research and Simulation of Photovoltaic System MPPT Control Based on Fuzzy Algorithm
Authors: Zhang Li Ping , Zhu Yao Fu , Fan Zhong
Published: August 2013

The maximum power point tracking (MPPT) control implements an effective utilization of solar energy. On the basis of the equivalent mathematical model of the photovoltaic (PV) array, presents the fixed step size perturbation and observation method, which has considerable power loss and poor adaptability. Because the existing variable step size control is complex, a fuzzy algorithm controller was designed according to the power variation and the previous step of the duty cycle, which could adjust the duty cycle of PWM dynamically, to make the PV system impedance matching and obtain the maximum power rapidly and steadily. The simulation shows that the self-optimizing fuzzy control can achieve good adaptability and good robustness when the parameters change.
The Motion Analysis of Loose Material on the Horizontally Circle Vibrating Drier
Authors: Zhang Zhen Wei , Kang Cheng Ming , Ji Xiang Lei , Zhou Tao
Published: August 2013

This article sets up the equations of material in the horizontally circle vibrating drier. According to basic theories of hydrodynamic and vibration, which gets the operating period and time expression of the material on the single hole panel of drier. According to equations, model erected on the computer simulate operating time of the material in the random position of the drier. The imitating data can match practical ones very well.
A Nonlinear System Research Based on PID General Algorithm Control
Authors: Hou Yu Bao , Tang Shu Yan
Published: August 2013

Generalized predictive control (GPC) algorithm has been applied to all kinds of industry control systems. But systemic and effective method for nonlinear system has not been found.To this problem,this paper integrates the characteristics of PID technology and GPC,present a PID generalized predicitive control algorithm for a class of nonlinear system,and improves the control quality of the system.
Strength of Concrete Based Cement Using Recycle Ceramic Waste as Aggregate
Authors: Al Bakri A.M. Mustafa , Norazian M.N. , Kamarudin H. , Mohd Salleh M.A.A. , Alida A.
Published: August 2013

The main focus of this research is to study the strength of concrete with ceramic waste as coarse aggregate. The sources of ceramic waste are obtained from the industrial in Malaysia. Presently, in ceramics industries the production goes as waste, which is not under going the recycle process yet. The potential of recycled ceramic waste as a substitute for coarse aggregates in concrete has been investigated. The recycle ceramic waste as aggregate was used. Concrete mixes with a 28 days characteristic strength of 20 MPa were prepared using water/cement ratio of 0.4, 0.5 and 0.7. The strength development of the concrete mixes containing recycled ceramic waste aggregates was compared to that of conventional concrete. The result show that the concrete mixes containing recycled ceramic waste aggregates achieve strength levels between 80 to 95 % compared to the conventional concrete. This indicates that the recycled ceramic waste has a potentially to be used as coarse aggregates for concrete.
Flow Stress Behavior and Microstructure Evolution Anisotropy of Extruded 7075 Aluminum Alloy Bar at Elevated Temperatures
Authors: Yang Yong Biao , Zhang Zhi Min , Wang Qiang
Published: August 2013

Hot compression tests of 7075 extruded bar were carried out on the Gleeble-1500 thermal simulation machine at strain rates of 0.1 s-1 and 1s-1 and at temperatures of 320°C. The compression direction are aligned at 0°, 45°and 90°to the axis direction of the extruded bar. Microstructure and texture was characterized using Optical Microscopy and x ray diffraction analysis. The results show that the true stress of all specimen increases with decreasing temperature and increasing strain rates. Both the yield strength and the stable flow stress of the 0° specimens is the highest among all three specimens, while that of 45° specimen is the lowest. This could be attributed to the lamellar grain structures and the texture of the extruded bar. The microstructure of 0°specimen are of equiaxed grain due to dynamic recrystallization after compression, while the grain shape of 45°and 90°specimens are still of lamellar grain structure.