bluuebunny/crossref_metadata_2025 huggingface dataset:
Challenges of Data Acquisition and Analysis for Characteristics-Driven and Metrology-Based Optimization of Milling Process Development
Authors: Niendorf Laura , Boeckmann Markus Grosse , Schmitt Robert
Published: December 2014

The research and practical use of data and data-mining in production environment is still at an early stage. Although almost every manufacturing company collects a lot of process and product related data they often do neither use nor deploy this data in order to optimize or even analyze their production processes. The acquisition of process data brings several advantages. On the one hand the implicit knowledge is permanently stored and on the other hand it is possible to learn from previous process failures. The acquired knowledge could then be applied to all future production tasks. Although many research activities can be observed since the late 90s, none of them managed the transfer to practical usage. In order to encourage the practical transfer of data-mining in production environment this paper presents a metrology-based test set-up and therewith arising challenges when consistently acquiring and processing inhomogeneous process, product and machine data. For the experimental set-up, on-machine metrology systems were developed and integrated into a 5-axis milling machine to gain much significant data.
A Novel Key Management of Wireless Sensor Network in Smart Substation
Authors: Zhang Yi Ying , Zou Wei Fu , Zhang Su Xiang , Wang Ben
Published: December 2014

Smart substations are deployed various types of sensors to monitor and control some devices and environment, and transmit the related parameters or data to the intelligent decision system. However, due to the limitation of resource, sensors tend to be captured or controlled by adversaries. In this paper, we present a dual-level key management based history keys, which can authenticate member sensors and their keys. Furthermore, we also adopt a cluster architecture, which cannot only localize the attack range but also reduce the energy consumption effectively. The security analysis shows our solution can verify the malicious node and authenticate key to protect the sense system in the smart substation.
Multidisciplinary Integrated Simulation and Design Optimization Framework for Electromechanical Servo System
Authors: Ding Wei Tao , An Lin Xue , Wang Chun Ming , Huang Yu Ping , Long Teng , Jiang Meng Long
Published: December 2014

This paper presents a tailored multidisciplinary integrated simulation and design optimization framework for electromechanical servo system (MISDOF-EMSS). The work intends to develop flexible integrated simulation techniques and efficient MDO methods to design advanced electromechanical servo systems in modern industries in a more effective and efficient manner. The proposed framework was developed based on ModelCenter commercial MDO framework because of its opening architecture for process integration and algorithm extension. The hardware and software configurations of MISDOF-EMSS were introduced at first in terms of the application requirements. Parametric geometry modeling toolkit was developed based on Pro-E, which provides the unique geometry source to link various disciplinary simulations. All the disciplinary analysis models were implemented in batch mode using automation techniques, and then seamlessly integrated in MISDOF-EMSS by using ModelCenter’s Filewrapper protocol. Advanced MDO methods including optimization algorithms, surrogate modeling techniques, MDO strategies are implemented in MISDOF-EMSS using Plug-in interface, VB script and Marco in ModelCenter. Finally, an application case of permanent magnet synchronous motor (PMSM) optimization was performed to verify the practicability and applicability of the proposed MISDOF-EMSS.
Study of the Milling Process for Thin Components Using a Flexible Setup Configuration
Authors: Nguyen Sy Quy , Chatelain Jean Francois
Published: December 2014

In the aerospace industry, numerous large parts with complex curvatures and several thin wall/web pockets are required to ensure stiffness and low weight for aircraft structures. Costly processes and dedicated setups are usually required to machine such thin plate components. Therefore, investigating new machining methods involving flexible setups for such parts is an interesting avenue for cost savings, but a big challenge as well, due to a lack of support and part flexibility. In fact, a flexible setup is a tooling system with several adjustable positioning supports, which can easily adapt to different workpiece geometries. In this paper, an experimental investigation of the machining of pockets for thin components using flexible setup is presented. A design of experiments is proposed to verify the ability of pocket machining for thin plates of aluminum 2024-T3 in terms of quality. During the machining tests, the cutting forces were measured using a Kistler dynamometer table, while the displacement of the plates, for the flexible setup configuration, was measured using a Keyence displacement sensor. The force and displacement signals were analyzed and a fine correlation proposed between them and the resulting quality of the part, expressed in terms of profile and size errors.
Nonlinear Identification of a PUMA Manipulator Arm MA2000
Authors: Poveda Rodríguez Diana Katheryn , Rodolfo Villamizar Mejía , Carreño Zagarra Jose Jorge
Published: December 2014

This article deals with the tuning of a simplified non-linear model that represents the dynamic behavior of the manipulator arm PUMA MA2000, where excitation signals formed by a finite sum of harmonics Fourier series were used in order to obtain arm dynamical responses. Initially, non-linear mathematical model is derived by using the Euler-Lagrange notation, and then a simplified nonlinear model is obtained and tuned by using the experimental angular position measurements for waist, shoulder and elbow robot joints.
Electrorheological Self-Amplifiying Microvalve
Authors: Freyer Holger , Heinken Helge , Krivenkov Konstantin , Breitfeld Andreas , Ulrich Stephan , Bruns Rainer , Wulfsberg Jens
Published: December 2014

This paper presents the design structure of an electrorheological self-amplifying microvalve for electrorheological fluids. This self-amplifying valve can thereby be devided into two main parts, the steering valve and the self-amplifying unit. The first step - combining a conventional electrorheological valve with a self-amplifying unit is one very important aspect and already induced to a promising result in the past. In a next step the conventional electrorheological valve is replaced by an electrorheological microvalve. Smaller dimensions are the final result. The simulation results of the whole system based on measurement results of the electrorheological microvalve are presented in this paper.
Artificial Neural Network Based Sensorless Vector Control of Induction Motor Drive
Authors: Niasar Abolfazl Halvaei , Khoei Hossein Rahimi , Zolfaghari Mahdi , Moghbeli Hassan
Published: December 2014

Controlled induction motor drives without mechanical speed sensors at the motor shaft have the attractions of low cost and high reliability. For these speed sensorless AC drive system, it is key to realize speed estimation accurately. This paper describes a Model Reference Adaptive System (MRAS) based scheme using Artificial Neural Network (ANN) for online speed estimation of sensorless vector controlled induction motor drive. The neural network has been then designed and trained online by employing a back propagation network (BPN) algorithm. The estimator was designed and simulated in Matlab. Simulation result shows a good performance of speed estimator. Also Performance analysis of speed estimator with the change in resistances of stator is presented. Simulation results show this estimator robust to resistances of stator variations.
H∞Control for Vibrations of a Wound Rotor Synchronous Machine
Authors: Geoffriault M. , Godoy E. , Beauvois D. , Favennec G.
Published: December 2014

This paper proposes a Hinfinity controller for current harmonics in a wound rotor synchronous machine. By reducing some specific current harmonics, it will be able to decrease the level of the corresponding harmonics in of the magnetic field and so of the vibration level induced by the force on the machine stator created by this field.
A New Approach in Digital Image Compression Using Unequal Error Protection (UEP)
Authors: Paul Okuwobi Idowu , Lu Yong Hua
Published: December 2014

This paper proposes a new algorithms for compression of digital images especially at the encoding stage of compressive sensing. The research consider the fact that a certain region of a given imagery is more important in most applications. The first algorithm proposed for the encoding stage of Compressive Sensing (CS) exploits the known structure of transform image coefficients. The proposed algorithm makes use of the unequal error protection (UEP) principle, which is widely used in the area of error control coding. The second algorithm which exploits the UEP principle to recover the more important part of an image with more quality while the rest part of the image is not significantly degraded. The proposed algorithm shown to be successful in digital image compression where images are represented in the spatial and transform domains. This new algorithm were recommended for use in image compression.
An Identification Method for Cracked Eggs Based on Image Wavelet Transform and Multi-Features Synthesis
Authors: Xiong Li Rong , Zhu Zhi Hui
Published: December 2014

An identification method for cracked eggs by means of the digital image technology was proposed in this paper. Firstly, an ideal machine vision system was built and the images of good eggs and cracked eggs were obtained by CCD camera. Secondly, each image was decomposed on two layers of wavelet, so 6 high-frequency sub-images and 2 low-frequency sub-images were extracted. Then joint probability matrix after wavelet transform had been calculated and 5 parameters for each high-frequency sub-images were extracted, so the total of the joint probability matrix parameters was 30 for 6 high-frequency sub-images. At the same time, 10 wavelet energy parameters were obtained. Thirdly, four main factor component scores were selected from above 40 feature parameters after principal component analysis, which were input to support vector machine. Finally, classification model was built by support vector machine. Experiments show that the proposed method was effective to identify the cracked eggs from good eggs and the identification rate was 93.75%.
Dynamic Analysis of Variable Stiffness Bracing System in Structure
Authors: Fateh Amir , Hejazi Farzad , Jaafar Mohd Saleh , Abd. Karim Izian , bin Adnan Azlan
Published: December 2014

In this paper, the application of a variable stiffness bracing (VSB) system in structures subjected to earthquake excitation is presented. The considered variable stiffness system is includes of four curve leaf springs. The nonlinear geometry of leaf springs which are acting as bending component lead to nonlinear stiffness performance. The variable stiffness bracing system does not act much for small to intermediate vibration amplitudes but it’s operated to control unpredictably large story displacement. It means this retrofit’s technique avoid an increase force in structural component due to ordinary brace action. The single degree of freedom system (SDOF) is considered and dynamic analysis of aforementioned system, with Bare and normal braced frames are conducted and the results are compared. The efficiency of the proposed system is discussed and proved in light of numerical analysis.
Serviceability and Structural Behavior of FRP-RC Beams under Different Weathering Conditions and Fatigue
Authors: Rahmatian Arash , Bagchi Ashutosh , Nokken Michelle
Published: December 2014

This research encompasses structural behavior of FRP-RC beams under fatigue and different conditioning. Twelve beams were designed, casted, and after 28 days, subjected to pre-cracking. This pre-cracking was designed to simulate the expected flexure cracks in service and to enhance the effects of subsequent exposure. The beams were then exposed to one of the following four conditions: control (indoor lab environment), immersion in alkaline solution, cyclic immersion in alkali solution (Wet and Dry or W&D condition), and outdoor exposure (local Montreal climate) for 14 month .Two potentiometers installed after pre-cracking at the mid-span for flexural crack and at the shear span and after every 50-100 thousands cycles crack mouth opening displacement (CMOD) measured .Deflection of the mid-span recorded at the same time and degradation of crack, and deflection versus number of cycles and life-span prediction with considering service limit state (SLS) elaborated in this research.
Design and Implementation of Logistics Management Information System Based on J2EE
Authors: Ren Yan Hua , Liu Duo Lin
Published: December 2014

Based on the current status of logistics management information system, this paper puts forward an information management system based on small and medium-sized logistics enterprises. This system is implemented by using mature J2EE open source technology, and it is simple, low maintenance cost, has strong scalability and high practical value.
Assessment of Life Cycle Greenhouse Gas Emissions from Coal Fired Power Plants in India
Authors: Nagarkatti Arun , Kolar Ajit Kumar
Published: December 2014

More than two third share of electricity come from coal fired power plants in India. Coal fired power plants are the largest source of anthropogenic CO2 emissions per unit of electricity generation among all fossil fuel based power plants. There has been climate change and global warming globally due to increasing anthropogenic emission of greenhouse gas (GHG) into the atmosphere. This paper examines life cycle GHG emission such as CH4, CO2 and N2O of a National Thermal Power Corporation (NTPC) Limited power plant using life cycle approach. The various stages involved in the assessment of life cycle GHG emissions in the present study include coal mining, transportation of coal to the power plant and coal combustion for electricity generation. The results show that direct CO2 emission from coal combustion is about 890 g CO2-e/kWh, whereas life cycle GHG emissions amount to 929.1 g CO2-e/kWh. Indirect GHG emissions add up to 4.2% of total emissions. Coal mine methane leakage into atmosphere in India is low since more than 90% of the coal mining is surface mining.
Specifics of Mathematical Simulation and the Method of Modeling for Subway Tunnels Thermal Conditions
Authors: Vasilyev G.P. , Peskov N.V. , Gornov V.F. , Kolesova M.V. , Dmitriev A.N. , Yurchenko I.A.
Published: December 2014

This paper contains the results of research, carried out with financial support from the Ministry of Education and Science of the Russian Federation and dedicated to improving the energy efficiency of Moscow subway facilities and creation of stations with "zero" external sources heat consumption. The paper presents a method of simulation of the thermal conditions for subway tunnels, which allows, overcoming the difficulties associated with the informative uncertainty of baseline data, as well as difficulties associated with the approximation of the external parameters. Advantage of this method is the fact that the usage of so-called "base" experimentally obtained information about the natural soil thermal conditions in this model, can partially take into account the whole range of factors, which have significant influence on the formation of the thermal regime of the tunnel but are almost impossible to be taken into account within the strict formulation of the problem today.
Studies on the Ultra-Low NOx Burner Technology Using Partial Oxidation Reaction
Authors: Kim Se Won , Lee Chang Yeop , Kwon Min Jun
Published: December 2014

A new concept of low NOx burner, based on a partial oxidation combustion concept, is successfully applied in this research. The burner is designed such that a portion of liquid fuel is heated and pre-vaporized in the furnace then injected into a fuel rich combustion zone so that a partial oxidation reaction occurs. The effects of equivalence ratio, thermal load, and fuel distribution ratio on the emissions of NOx and CO are experimentally investigated. This newly developed burner showed very low NOx emission level, about 12 ppm, when light oil is used as a fuel.
Trooper Seat Attachment Design and Analysis
Authors: Piangpen P. , Attapon C.
Published: December 2014

In order to protect the army troopers, it is important to consider the assessment of hazardous areas in the military vehicle, attacked by the enemy. For armored vehicles, the design, analysis, and test of explosive seat protection are significant to ensure the trooper survivability. Particularly, we note that the significant factor affecting the trooper survivability is ability of trooper seat to absorb shock generated by the explosion. Therefore, this research focused on the design and analysis of trooper seat attachment for armored vehicles. The research proposed various designs of the trooper seat attachment. Then, the designed seat attachments were analyzed using the numerical simulation to investigate conditions and variables that impact the trooper survivability. The results showed the efficient trooper seat attachment design, while maintaining the mine blast protection capability.
A Processing Approach Incorporating Copper Backing-Wheel Device in Submerged Arc Welding for Manufacturing Cryogenic Storage Tanks
Authors: Rajsiri Supphachan , Chomjanngam Mayuree , Tuntawiroon Sittiphun
Published: December 2014

A processing approach using a copper backing-wheel device was developed to aid the fabrication process of industrial cryogenic storage tanks manufactured under the ASME Section VIII Division 1. This research focused on the welding processes related to the cylindrical-body assembly. Two processing steps involving the root-run formation and the replacement with a sound outer-circumference joint were studied. Initially, tank fabrication is achieved through the application of both flux-cored arc welding and submerged arc welding. A new processing approach was proposed with the modified method in cross-section preparation, and a low-cost reusable copper backing-wheel device was developed to facilitate the root-run formation using only submerged arc welding. Temperature gradient through the device components along the heat-conduction path was monitored to assure the conductivity of the backing device. The results suggest that the proposed approach reduced manufacturing time by removing the initial flux-cored arc welding process used in the conventional welding method. As an effect, the new approach show promise reduces the overall manufacturing cost of tank fabrication. Based on radiographic testing of tanks fabricated using the new approach found that circumference joints required little or no welding repair suggesting higher joint quality.
The Design of Self-Erection Derrick of Simple Offshore Workover Rig
Authors: Gai Yong Ge , Zhang Zuo Long
Published: December 2014

Though the use of modular technology, a sub-vertical lifting offshore workover rig derrick for the marine small platform is designed, which can be installed and moved quickly. The overall derrick structure and most of the part design and selection are completed by Solidworks and Auto CAD. The static calculation for the derrick is done with the help of finite element analysis software ANSYS, and analyzed the results to ensure that the derrick designed could meet the strength requirements.
Increase in Accuracy and Smoothness of Movement of the Mechatronic Unit of Linear Micromotions
Authors: Novikova Elena , Shtykh Dmitry , Zhdanov Alexey , Morozov Valentin
Published: December 2014

Application spheres of exact linear motions actuator were examined. Typical complexes of requirements to parameters of movement of the output link were defined. Methods of evaluation of the quality of movement of the output link were carried out. The analysis of possibilities of the technical characteristics increase of linear micro motions actuators was carried out. The method of increase in accuracy and smoothness of motion of the output link actuators through optimization of the management system based on kinematic error of the actuating mechanism was examined.
Natural Convective Coutte Flow in a Vertical Parallel Plate Microchannel
Authors: Narahari Marneni , Pendyala Rajashekhar
Published: December 2014

In the present paper, the exact analysis of steady state fully developed natural convective Couette flow in a vertical parallel plate microchannel is performed. Exact solutions are derived for the dimensionless velocity, temperature, volume flow rate, vertical heat flux and Nusselt number. The effects of Grashof number, wall-ambient temperature difference ratio and Knudsen number on the velocity, volume flow rate and Nusselt number have been discussed through graphs. The study revealed that the fluid velocity and volume flow rate increases with increasing Grashof number whereas the Nusselt number decreases with increasing Grashof number.
Enhancing Sustainable Recycle Solid Waste to Porous Activated Carbon for Methane Uptake
Authors: Nasri Noor Shawal , Noorshaheeda Ramlan , Hamza Usman Dadum , Mohammed Jibril , Ahmed Murtala Musa , Mohd Zain Husna
Published: December 2014

Potential agro wastes (i.e palm kernel shell and coconut shell) for producing low cost activated carbon (AC) was investigated. In this study, the activated carbon was produced by carbonization, chemical impregnation with KOH and microwave irradiation. The pyrolysis was carried out at 700 °C in an inert environment for 2 h. Microwave activation was carried out at 400W for 6 minutes. Characteristics of the material were investigated using Fourier transform infrared spectroscopy (FT-IR) analysis and scanning electrode microscopy (SEM). Methane adsorption equilibrium data on the activated carbons produced were obtained using static volumetric method. Microwave palm shell activated carbon (MPAC) and microwave coconut shell activated carbon (MCAC) recorded highest methane uptake of 2.489 and 1.929 mmol/g at 3 bar, 30°C. The adsorption data were correlated with Langmuir and Freundlich isotherms. The results shows that microwave activated carbon from palm shell and coconut shell have good methane adsorption characteristics.
Design of Intelligent Resistivity Measurement System
Authors: Qi Shu Fen , Zhang Kun
Published: December 2014

Accurate measurement of the drilling mud resistivity is very important to analysis of drilling parameters. Therefore, it is necessary to produce an accurate measurement system. The resistivity measurement system which is introduced in this paper adopts STM8s single chip microcomputer as the control center. It sends control commands via I2C technology and completes the measurement of resistivity using AD5933. Then data is sent to the MCU. When the MCU deals with the data, LCD screen displays measurement results. The system has so many advantages: low power, portable, real-time measurement etc. It provides a reliable basis for analyzing the parameters of drilling.
Effect of Structure and Thickness on the Electrical Characteristics of QLED Device
Authors: Gao Hui , Li Deng Hua , Ma Hang
Published: December 2014

For the interface heterostructure between metal and organic layer of Quantum dot light-emitting diodes (QLED), tunneling injection model Fowler-Nordheim (F-N) was used to analyze the electrical characteristics of QLED. Through analyzing different thickness and the potential barrier of metal organic layer interface of QLED structure, simulation by Matlab obtained the J-V characteristic curves of the injection limit current density and the driving voltage. The simulation results showed that reducing the whole device thickness and the barrier height of metal organic layer interface of QLED structure, the energy consumption will be decreased. That is to say, carriers injection properties can be improved with the thinner device and lower barrier height, operating at the same voltage.
Development of Adaptive Distance Relay for STATCOM Connected Transmission Line with Wavelet Transform and ANN
Authors: Hasabe Ramchandra P. , Vaidya Anil P.
Published: December 2014

A new scheme to enhance the solution of the problems associated with Transmission line protection with Statcom connected is presentedin this paper.Static Synchronous Compensator (STATCOM) is a shunt type FACTS device connected at the midpoint of the transmission line to maintain the voltage atdesired level by injecting/absorbing the reactive power. This connection affects the performance of distance protection relay during line faults. Thefault detectionis carried out byusingenergy of the detail coefficients of the phase signals and artificial neutral network algorithm used for fault distance location for all thetypes of faults for transmission line. For each type of fault separate neural network is prepared for finding out the fault location.
Sustainable Recycle Solid Waste to Synthetic Renewable Solid Energy
Authors: Nasri Noor Shawal , Mohd. Zain Husna , Mohammed Jibril , Hamza Usman Dadum , Ahmed Murtala Musa
Published: December 2014

Renewable energy is a source of energy that can be recovered and recycled. The recyclable material is removed first before energy is recovered from the residual waste. In this study, the effect of pyrolysis temperature on the calorific value of sustainable materials and gas emission quality were carried out. Pyrolysis and non-pyrolysis processes were initially conducted before calorific value determination. Calorific values of the samples were measured by bomb calorimeter. The sample that contains the highest calorific value was chosen and compared with coal. Testing of the prepared samples was accomplished using combustion process. The characterizations of the samples were determined by TGA analysis, SEM, FTIR and elemental analysis. From the results obtained, it is observed that the calorific value of sustainable material depends on the number of hydrogen, carbon and thermal energy.
Application of Remanufacturing Technology in Imported Roll EDT Machine
Authors: Zuo Zhi Yong , Jiang Li , Zhan Yi Qing , Yang Li
Published: December 2014

This paper introduced application of imported EDT machine in domestic steel companies, as well as the structure and working principle of SM EDT generator that was manufactured by KLEINKNECHT Company. It discussed the repair feasibility and economic value from perspective of remanufacturing, and introduced detection method of module and actual waveform by example.
Time-Domain Analysis and Experimental Verification of Portable Grounding System’s TGR
Authors: Qu Xin Bo , Zhou Bi Hua , Fu Ya Peng , Yang Li Juan , Zhang Nan
Published: December 2014

The portable grounding system plays an important role in the lightning protection system of mobile equipments. But the traditional earth electrodes composed of vertical rods wouldn’t work well or would take a long time to set up in some conditions such as frozen soil, hard clay and so on. In this paper, a new type of portable grounding system which can be quickly spread and folded has been designed. To analyze the TGR’s (Transient Grounding Resistance) time-domain characteristics, the grounding systems have been modeled and simulated with FDTD (Finite Difference Time Domain). The influence rule of electrodes’ number and down-lead’s position to TGR has been studied with numerical analysis and validated with experiments. The results show that the new grounding system works well even on cement floor.
Short-Term Wind Power Forecasting in Wind Power Plants of North China Based on Support Vector Regression Analysis
Authors: Shao Hai Jian , Wei Hai Kun
Published: December 2014

This paper investigates the short-term wind power forecasting and demonstrates accurate modeling, which utilizes two representative heuristic algorithms (i.e. wavelet neural network (WNN) and Multilayer Perceptron (MLP)), and statistical machine learning techniques (i.e. Support Vector Regression (SVR)). The proposed method generates the performances of different approaches for random time series, characterized with high accuracy and high generalization capability. The employed data is obtained through Sampling equipment in Real Wind Power Plants (Power generation equipment is Dongfang Steam Turbine Co., Ltd. weak wind turbine type--FD77 with German REpower company technology). The main innovation of this paper comes from: (a) problem may encounter in the real application is in consideration such as corrupt, missing value and noisy data. (b) Data lag estimation are provided to investigate the data distribution and obtain the best input variables, respectively. (c) Comparison between MLP neural networks, WNN and SVR with optimized kernel parameters based on Grid-search method are provided to demonstrate the best forecasting approaches. The purpose of this paper is to provide a method with reference value for short-term wind power forecasting.
Characteristics of Nanostructured TiO2 Prepared by One-Step Soaking Method for Photovoltaic Application
Authors: Park Mi Sun , Sung Shi Joon , Kim Dae Hwan
Published: December 2014

Nanostructured TiO2 films were prepared by a one-step soaking method, which has many advantages, such as simple fabrication, a short reaction time, and fast growth. We have investigated the growth of TiO2 films by the substrate orientation of the soaking method, which had an effect on the nanostructure of the TiO2 films. The TiO2 films prepared by this method had various structures: particulate-flat structure and sphere-flat structure. To determine the effect of the nanostructure of TiO2 films on the photovoltaic characteristics of solar cells, solar cell devices using the inorganic semiconductor Sb2S3 as a sensitizer were fabricated by chemical bath deposition (CBD). Our solar cell device, using TiO2 film with a sphere-flat structure as a photoelectrode, exhibited JSC, VOC, FF, and η values of 11.82 mA / cm2, 0.49 V, 30.27 %, and 1.74 %, respectively.
Solar-Diesel Hybrid Model and Control for Central Heating
Authors: Abdalla Musa , Emran S. , Mukhtar M. , Nabil A. , Tahboob Z.
Published: December 2014

A complete technical study on a Hybrid heating system is carried out with the aid of computer simulation. The main objective of this work was to provide more insight into combining Solar and Diesel energies to be utilized in domestic central heating. The motivation for such a system was basically the ever increasing Diesel prices in the Kingdome. This work revealed that the cost of Diesel in heating houses could be lowered by at least fifteen percent if the hybrid system is implemented. Complete mathematical model of a representative house was derived for the sake of computer simulation. The model was validated and verified through computer simulations (Matlab Simulink based) with real collected weather data of Jordan (complete year record). Finally a controller strategy was devised and tested using the derived mathematical model.
Research on Correction to Fitting Factors of Shape Function and Convergence of Wind Turbine Airfoils
Authors: Chen Ya Qiong , Fang Yue Fa , Guo Sheng , Chen Zhi Hong
Published: December 2014

Based on the functional expression methods of wind turbine airfoils, the method of the correction to parameter factors of shape function by iterative calculation in the principle of making the residual error minimum between the fitting airfoil and the target airfoil is presented in this paper, which makes the fitting precision improved compared with the parametric representation of original airfoils. The method of the correction to parameter factors of shape function proposed in this paper is used for parametric representation of more than 20 kinds of typical airfoils and then the geometric and aerodynamic convergence are intensive studied. The results show that the minimal order of the integrated expression of airfoils is decreased by the proposed method in this paper and the mathematical models of airfoils which facilitate the unification of optimal design are established.
Effect of Anti-Reflective Layer in Dye-Sensitized Solar Cells
Authors: Nam Jung Eun , Jo Hyo Jeong , Son Dae Ho , Kim Dae Hwan , Kang Jin Kyu
Published: December 2014

Anti-reflective (AR) layers play an important role in boosting the amount of light entering a device and reducing reflection losses in a device, thereby enhancing the power conversion efficiency of solar cells. We have coated an AR layer on the surface of a dye-sensitized solar cell device by using an electron beam evaporation system and investigated the effects of the AR layer by measuring photovoltaic performance. The AR layer is found to increases the Jsc and η of the solar cell.
Research on the Application of Fuel Cell in the Electricity-Generating Industry
Authors: Hu An Liang
Published: December 2014

In this paper, the internal structure and category of fuel cell were firstly described as well as the electricity-generating system. In addition, the current situation of the application of fuel cell in the electricity-generating industry was discussed including its prospects. In the end, the assumption of the application of fuel cell in the electricity-generating industry was explored.
Fault Diagnosis of Wind Turbine's Converter Based on Memristive Neural Network
Authors: Wang Yun Liang , Wang Xun
Published: December 2014

In this paper, a memristive neural network was applied to fault diagnosis of wind turbine's converter. A model of memristive neural network was built in order to diagnose and analyze of the failure information by MATLAB Simulink. Experimental results show that the proposed method can achieve better results and has certain significance for the application of memristors widely used in the near future.
Preparation and Characterization of Hot Wall Deposited CuInGaSe2 Thin Films for Solar Cell Applications
Authors: Arul S. , Muthukumarasamy N. , Kannan M.D. , Jayakumar S.
Published: December 2014

CuIn0.7Ga0.3Se2 (CIGS) bulk compound was prepared by direct reaction of high purity (99.99%) elemental copper, indium, gallium and selenium. Using the prepared bulk CIGS, polycrystalline CuInGaSe2 thin films were deposited onto well cleaned soda-lime glass substrates using hot wall deposition technique by optimizing process parameters such as the wall temperature, filament current and time of deposition. The x-ray diffraction studies on the as-prepared films revealed polycrystalline nature. The composition of the chemical constituents present in the prepared bulk and thin films has been determined using energy dispersive X-ray analysis (EDX). The surface morphology of CIGS thin film of deposition time 3 min. have been carried out using Atomic Force Microscopy (AFM). The AFM images revealed that the average grain size was 20 nm and the surface roughness was about 8 nm. Transmittance spectra in the wavelength range of 190 nm to 2500 nm was obtained using a double beam spectrophotometer (UV-VIS) and the results are discussed.
Multi-Objective Optimization of a Two-Disk Rotor System
Authors: Huang Jing Jing , Zheng Long Xi , Qing Mei
Published: December 2014

A two-disk rotor system under the aero-engine support structure of typical 1-0-1 was established and the dynamical characteristics were analyzed. The two-disk rotor model was integrated to the Isight. The multi-objective design optimization of the transient process was then carried out with Evolutionary Optimization Algorithm. The optimum positions of the two-disk rotor system were obtained at the specified constraints. In order to verify the validity of the design optimization, the transient test was carried out on a high-speed flexible rotor mockup. The maximum amplitude of disk 1 cross the first critical rotation speed fell 50% and the maximum amplitude of disk 2 decreased by 20%. Experimental results indicated that the optimization method could obtain the position of the flexible rotor with the minimum amplitude and improve the design efficiency and quality, which had practical significance in the design of aero-engine rotor system.
Natural Materials for Thermal Insulation: Mulch and Lava-Rock Characterizations
Authors: Jean Aurélien P. , Adams Craig , Medina Mario A. , Miranville Frédéric
Published: December 2014

This paper reports on the thermal characterization, via the thermal conductivity, of natural materials, such as mulch and lava rock and their usefulness as building insulation. Experiments were carried out using a scale one monitored wall (i.e. heat flux and temperature sensors) exposed to a heating source on one side and to an air conditioned space on the other. The wall system was composed of an 8.85 cm thick cavity, where the mulch and lava rock were placed. The cavity was enclosed between two layers of pine wood (40 mm thick each). After the experiments and statistical data manipulation, the estimated thermal conductivity of the materials were 0.48 ± 0.001 W.m-1.K-1 and 0.129 ± 0.003 W.m-1.K-1 for mulch and lava-rock, respectively. That is, mulch has a thermal conductivity comparable to that of bulk hemp while lava rock has a thermal conductivity comparable to that of hemp brick. These values indicate the usefulness of mulch, compared to the impracticality of using lava-rocks materials for building insulation.
Comparison of the Strength Analysis about Single Bogie Frame and its in the Assembly
Authors: Wang Quan Xian , Dai Qi Hui , Sun Jing Jie , Wu Wei Hong
Published: December 2014

To take The CRH3 EMU bogie frame as the research object, aiming at the characteristic and mechanical performance of bogie frame, the 3D model of CRH3 bogie frame based on PRO/E are established. According to the standard TB/T 2368-2005 Motive power bogie frame structure strength tests, the load condition is defined. The strength analysis by finite element analysis software ANSYS are carried out in the bogie and single frame . The analysis results show that the maximum stress value of the selected node is less than the permissible stress in both cases, the strength analysis result of the bogie frame is more credible because the load processing is more close to the actual stress.
SMA Damped Tape Spring Hinge for Quasi-Static Deployment of a Satellite Solar Array
Authors: Jeong Ju Won , Shin Kum Cheol , Kim Kyung Won , Lim Jae Hyuk , Lee Jung Ju
Published: December 2014

A tape spring hinge is one of the most typical deployment devices and is frequently used in miniaturized satellite due to its simplicity, lightweight, low cost and high deployment reliability. But a tape spring hinge mechanism has limited performance due to the performance trade-off between deployed stiffness and latch-up shock.In this study, to improve a conventional tape spring hinge mechanism, SMA damped tape spring hinge is proposed so that a satellite solar array can be quasi-statically deployed. The test result shows the feasibility of the proposed concept.
Editorial Dynamics and Control of Aerospace and Vertical Transportation Systems
Authors: Balthazar José M. , Gonçalves Paulo Batista , Kaczmarczyk Stefan , Fenili André , Silveira Marcos , Navarro Ignacio Herrera
Published: December 2014

This Special Issue presents a selection of papers initially presented at the 11th International Conference on Vibration Problems (ICOVP-2013), held from 9 to 12 September 2013 in Lisbon, Portugal. The main topics of this Special Issue are linear and, mainly, nonlinear dynamics, chaos and control of systems and structures and their applications in different field of science and engineering. According to the goal of the Special Issue, the selected contributions are divided into three major parts: “Vibration Problems in Vertical Transportation Systems”, “Nonlinear Dynamics, Chaos and Control of Elastic Structures” and “New Strategies and Challenges for Aerospace and Ocean Structures Dynamics and Control”.
On the Delayed van der Pol Oscillator with Time-Varying Feedback Gain
Authors: Hamdi Mustapha , Belhaq Mohamed
Published: December 2014

This work studies the effect of time delayed feedback on stationary solutions in a van derPol type system. We consider the case where the feedback gain is harmonically modulated with a resonantfrequency. Perturbation analysis is conducted to obtain the modulation equations near primaryresonance, the stability analysis for stationary solutions is performed and bifurcation diagram is determined.It is shown that the modulated feedback gain position can influence significantly the steadystates behavior of the delayed van der Pol oscillator. In particular, for appropriate values of the modulateddelay parameters, the existence region of the limit cycle (LC) can be increased or quenched.Moreover, new regions of quasiperiodic vibration may emerge for certain values of the modulatedgain. Numerical simulation was conducted to validate the analytical predictions.
Current and Speed Control Operating Modes of a Reaction Wheel
Authors: Carrara Valdemir , Kuga Helio Koiti
Published: December 2014

This paper presents some approaches to the design and some experimental results for current and speed control loops of a reaction wheel (RW). Reaction wheels are largely employed in satellite attitude control due to its large range of torque capability, small power consumption and high reliability. However, to achieve such performance the RW design shall deal with several restrictions, such as to support the space environment hazards (radiation, vacuum, high and fast temperature variation), and launch requirements (vibration, noise and choke). In this work some experimental results of an air-bearing table attitude control equipped with a Fiber Optics Gyro (FOG), a reaction wheel and a small fan will be presented. The RW is controlled by speed reference, and a second speed mode control similar to the first one was implemented in an external computer. Both were then compared by means of the air-bearing attitude control performance during the wheel zero-speed crossing. The results showed that the controllers have similar performance, as expected, and the maximum attitude pointing error remained below 0.08 degrees, which complies with the attitude requirements of Earth pointing satellites.
The Rigid-Flexible Two Link Manipulator with Joint Friction and Different Number of Modes for the Flexible Link Discretization
Authors: Fenili André
Published: December 2014

A Rigid-Flexibletwo Link Rotatingmanipulator Likesystem is Mathematically Modeled Usinglagrange’s Equations. Two Different Approaches are Considered for the Flexible Linkdiscretization:(a) only the First Flexuralmode is Considered and (b) Two Flexural Modes are Considered. the Mainidea here is to Investigate the Participation of the Second Flexural Mode in the System Dynamics Forslow and Fast Maneuversin the Presence of Friction Forces. Nonlinearity Arises in this Problem Fromthe Coupling between the Variable Representing the Angular Velocity of the Rotating Axis Connected Tothe Flexible Link and the Variable Representing the Vibration of the Flexible Link. Sufficiently Largeangular Velocities are Considered in Order to the System to Undergo Sufficiently Strongnonlinearbehavior.Coulomb Friction Isconsidered on both Joints.For Position/velocity of both Rotating Axesand Elimination of Vibration in the Flexible Link the Nonlinear Control Technique Named Statedependent Riccati Equation (SDRE) is Applied. Theresults for the Different Mathematicaldescriptions of the System are Compared and Discussed
Nonlinear Analysis of Unbalanced Mass of Vertical Conveyerwith Non-Ideal Exciters
Authors: Bayıroğlu Hüseyin
Published: December 2014

In the area of mechanics and electronics, the behaviors of mechanical systems under periodic loadings have been examined by many researchers. Vertical conveyors are effective examples observing various kinds of parameters of this problem. In this study, the nonlinear analysis of unbalanced mass of vertical conveyor with non-ideal DC motor has been analyzed. The results of numerical simulation are plotted and Lyapunov exponents are calculated.
The Effect of Internal Flowing Fluid on the Non-Linear Behavior of Orthotropic Circular Cylindrical Shells
Authors: del Prado Z.J.G.N. , Argenta A.L.D.P. , da Silva F.M.A. , Gonçalves Paulo Batista
Published: December 2014

The great use of circular cylindrical shells for conveying fluid in modern industrial applications has made of them an important research area in applied mechanics. Many researchers have studied this problem, however just a reduced number of these works have as object the analysis of orthotropic shells. Although most investigations deal with the analysis of elastic isotropic shells in contact with internal and external quiescent or flowing fluid, several modern and natural materials display orthotropic properties and also stiffened cylindrical shells can be treated as equivalent uniform orthotropic shells. In this work, the influence of internal flowing fluid on the dynamic instability and non-linear vibrations of a simply supported orthotropic circular cylindrical shell subjected to axial and lateral time-dependent loads is studied. To model the shell, the Donnell’s non-linear shallow shell theory without considering the effect of shear deformations is used. A model with eight degrees of freedom is used to describe the lateral displacements of the shell. The fluid is assumed to be incompressible and non-viscous and the flow to be isentropic and irrotational. The Galerkin method is applied to derive the set of coupled non-linear ordinary differential equations of motion which are, in turn, solved by the Runge-Kutta method. The obtained results show that the presence of the internal fluid and material properties have a great influence on the vibration characteristics of the shell.
Chaotic Vibrations in Multi-Mass Discrete-Continuous Systems Torsionally Deformed with Local Nonlinearities
Authors: Pielorz Amalia , Sado Danuta
Published: December 2014

The paper deals with nonlinear vibrations in discrete-continuous mechanical systems consisting of rigid bodies connected by shafts torsionally deformed with local nonlinearities having hard or soft characteristics. The systems are loaded by an external moment harmonically changing in time. In the study the wave approach is used. Numerical results are presented for three-mass systems. In the study of regular vibrations in the case of a hard characteristic amplitude jumps are observed while in the case of a soft characteristic an escape phenomenon is observed. Irregular vibrations, including chaotic motions, are found for selected parameters of the systems.
Mathematical Modelling of a Rotating Nonlinear Flexible Beam-Like Wing
Authors: Fenili André , Francisco Cayo Prado Fernandes , Burr Karl Peter
Published: December 2014

The mathematical modelling of rotating nonlinear flexible beam-like wing with rectangular cross section is investigated here. The structure is mathematically modeled considering linear curvature and clamped-free boundary conditions. The flexible wing has an angle of attack which is considered constant. Nonlinearities resulting from the coupling between the angular velocity of the rotating axis and the transversal vibration of the beam are considered. A drag force and a lift force acting along the beam length are also included in the mathematical model. The drag force is modelled as a turbulent drag effect. The lift force is modeled as a generalized force, using the strip theory. These forces are velocity dependent nonlinear excitations acting on the bean-like wing.