bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation and Effectiveness Analysis of Jamming on Inverse Synthetic Aperture Radar
Authors: Luan Jun , Yuan Yun Neng
Published: September 2013

nverse synthetic aperture radar (ISAR) is a kind of imaging radar with high capability. It plays an important role in military applications, such as target classification, recognition, identification and accurate weapon navigation. This paper establishes a simulation model of jamming for ISAR system based on the principle of ISAR imaging. Then, the several typical of noise modulation jamming experiments for ISAR are carried out. The simulation results are analysed through evaluating the jamming effect based on the entropy concept.
Fault Feature Extraction of Helicopter Rotor System Based on HHT Envelope Demodulation
Authors: Lu Chen , Du Xiao Wei , Liu Hong Mei
Published: September 2013

Helicopter rotor system (HRS), which is a key component without redundancy design, is of significant importance for flight safety. Working under demanding environment, HRS faults are hard to detect. This paper proposes a new approach based on Hilbert-Huang Transform (HHT) and envelope demodulation to realize HRS fault feature extraction under strong interference. Empirical mode decomposition (EMD) was used to decompose the vibration signal into several intrinsic mode functions (IMFs) first, then, Hilbert transformation was applied to the IMFs to get the envelopes. And at last, fast Fourier transform (FFT) was adopted with the IMF which was closely related to the fault features. This method can avoid the selection of center frequency and filter band in resonance demodulation method, therefore, it has good adaptivity. Two commonly occurring faults in HRS are simulated on a test rig to validate the performance and effectiveness of the proposed method. The experimental results demonstrate that the proposed method based on HHT envelope demodulation is effective for the HRS fault feature extraction.
Application of Image Processing to Computer Graphics
Authors: Chen Chun Yu , Wang Fu Cheng , Chen Xin , Cui Feng , Zhang Li Li , Zhang Chen
Published: September 2013

The examination of the Computer Graphics is basically the computer examination to investigate the drawing ability in universities in recent years. Based on many years of teaching practice and according to the transformation trend of the computer intelligent paper marking, the image processing technology is adopted, and the key information of the image is extracted, and the image similarity calculation program is compiled, and the CAD automatic paper marking function is implemented by the contrast of the students plots with the standard answer. Through the calculation examples, the grading results are consistent with the artificial results ideally. The calculation speed is faster than the manual speed, thus the teachers working efficiency is improved.
Fourier and Wavelet Analysis of Water Quality Signals
Authors: Zhang Wei , Li Hong , Sun Dan Feng , Zhou Lian Di
Published: September 2013

Taking the nitrogen monitoring data of two sites S1 and S2 in the period 1988-2003 in Baihe River lying Miyun reservoir stream watershed as a case, Fourier and Wavelet analysis were adopted to explore and compare the periodic patterns and temporal pattern characteristics of the two sites. The results showed that the periodic patterns of two sites were discovered using Fourier analysis. The site S1 had a period of two years, while the site S2 had no significant periodic patterns. The temporal pattern characteristics at different scales were obtained through wavelet analysis, which were at small scale for the site S1, while at moderate and small scales for the site S2. The Fourier and wavelet analysis method can both be used in the study of surface water quality temporal change pattern, the first is a coarse method and the latter is a more detailed method for analyzing surface water quality temporal pattern characteristics.
General Structure Layout and Design of Target Area of SGIII Facility
Authors: Zhu Ming Zhi , Chen Xiao Juan , Wang Mei Cong , Wu Wen Kai , Chen Gang , Wang Bao Xu
Published: September 2013

ShenGuang III (SGIII) facility will be constructed for research in Inertial Confinement Fusion. In this paper, general structure layout and design of target area of SGIII facility are described. Target area structure support system must provide a stable and precisely platform for optical elements before and during a shot. General structure layout must satisfy the mul-function consideration and logistic priority. The modularity and hardware commonality, cleanliness, and low neutron activation should be considered in the structural design of target area. The general structure layout of target area is rectangle. The target bay and the switchyard have the multi-layered layout to satisfy the demand of transporting beam lasers unidirectionally from south to north and supporting the optics modules and physical diagnostic instruments with different height. The passageways of population & goods flow of target area are designed to include the vertical channels between the different layers and the horizontal channels on the same layer. The opto-mechanical elements (OM) are classified as OM1, OM2, and OM3. The OM1 are the infrastructures. The OM2 include target chamber, the shell of final optics assemblies, the mirror frames, and the beam enclosures. The OM3 is line replaceable units that are attached to the OM2 on kinematic equivalent three-vee mounts.
Study on Non-Point Source Pollution in the Agricultural Watershed
Authors: Xiang Long , Zhou Peng Fei , Chen Xue Gao , Zhu Yong Shu , Yu Zhong Bo , Chen Xing
Published: September 2013

This paper gives a review on the study of related factors of non-point source pollution (NPS) in water cycle. Hydrological process features, underlying surface conditions, human activities are sorted to introduce the recent research on NPS progress. Several major factors are divided in each item with developing process. The NPS models in world are introduced as well. Additionally, control approaches for NPS and their effects are summarized. Furthermore, the potential trends of NPS study are discussed.
Study on Public Awareness and Participation in Environmental Protection in China
Authors: Zhang Wen Hua
Published: September 2013

The awareness for public participation and environmental protection in China are weak, their activities to participate are in lower class which shows short of more people, reasonable mechanism and efficient result. This paper is based on the characteristics from public participation in environmental protection to describe the current conditions in China. Then it analyzes the phenomenon, points out being problems and puts forward some solving methods.
Numerical Modeling of the Hydrodynamics for Zhuanghe Fishing Port
Authors: Li Xin , Xie Ming Xiao , Li Meng Guo
Published: September 2013

The offshore areas belong to the marine terrestrial interaction region. There are complex hydrodynamic factors, which influence each others and controlled transport of sediment and contaminant near shore. The paper builds up a wave-current coupling hydrodynamic model with Mike21 software package. After validation and calibration, the model is applied to wave and tidal current simulation on Zhuanghe fishing port project. The results show that the large area flow field is substantially unchanged after project construction and the effect is restricted to a small region near around the fishing port.
Snow Disaster Risk Assessment in China Based on Environment & Disaster Monitoring and Predicting Small Satellite
Authors: Lv Chao , Gong Hui Li
Published: September 2013

The snow disaster is one of the main disasters in prairie pastoral areas of China. Once the snow disaster occurs, it will cause the death of a large amount of livestock due to the starvation and freezing weather. Therefore, it is especially important to forecast the risk of the snow disaster scientifically and reasonably. This paper proposed the snow disaster risk assessment model in pastoral areas based on the data of environment & disaster monitoring and predicting small satellite. Considering the random of snow disaster's occurrence and the fuzziness of snow disaster risk assessment, fuzzy math method was introduced in the study of snow disaster risk assessment. After the massive experiment monitors and the contrast confirmation with the disaster situation data in National Disaster Reduction Center, the model forecasting result and the disaster situation statistical data have good uniformity from the space position and the risk degree. Study shows that the snow disaster risk assessment model is practical and feasible, and it provides important scientific method to further improve snow disaster risk assessment ability in pastoral areas.
Construction of Commercial Age of Enterprises in Eco-Industrial Parks - A Case Study of Xishan Eco-Industrial Park
Authors: Zhu Lin , Xu You Peng , Sun Qin Fang
Published: September 2013

The article proposes the methods to construct the commercial age of enterprises in eco-industrial parks by taking the concept of commercial age as a starting point. With Xishan Eco-industrial Park as an example, it also carries out an empirical study by selecting three enterprises from each of the three representative industries. The research results show that the enterprise age as a representative indicator reflects the characteristics of the development of eco-industrial parks and the changes of the eco-industrial structures. In this way, it will provide theoretical and practical guidance for reasonable construction of commercial age structure while maintaining the industry chain of eco-industrial park and the industrial ecosystem stability.
The Investigation for the Purification of a Recycling Aquaculture System
Authors: Deng Chao Bing , Liu Ya Qing , Xian Ping , He Jun He , Wang Xiao Fei , Li Xiao Ping , Xu Ying Bo , Tang Ming
Published: September 2013

With the design of the aquiculture system, the purification effect was studied to provide the basis for the ecological aquiculture model. The research results show that the organic pollutants and ammonia nitrogen concentrations were reduced to below 5 mg/L and 0.5 mg/L in the system; When the concentration of CODMnkeeps above 8 mg/L, the ammonia nitrogen can be removed efficiently; The system is capable for resistance shocking, when the concentration of CODMnincreased to more than 65 mg/L or ammonia nitrogen concentration increased to more than 6 mg/L, the system can keep a high purification effect.
The Effect of Inclusions on the Formation of Intragranular Ferrite
Authors: Bu Fan Zheng , Wang Xue Min
Published: September 2013

In order to make a more intuitive and easier analysis the influence of different inclusions on the formation of ferrite, a layer of high purity oxide powder was added in the two parts of the Q235 steel artificially. The effect of the inclusions Ti2O3MgOZrO2 and Al2O3 on the nucleation of intragranular ferrite were studied by means of the physical simulation method. The microstructure of the micro-zone adjacent to the inclusions was observed and the elements of the micro-zone adjacent were analyzed. The results showed that the inclusions Ti2O3 and Al2O3 can form the ferrite layers at the oxides-steels interface; the inclusions Ti2O3 has an ability to induce the nucleation of intragranular ferrite; the inclusions Ti2O3 can change the chemical composition of the metal micro-zone adjacent to the inclusions, where the Mn depletion area was observed.
Determination of Evaluation Indicators Weight for Comprehensive System Based on Rough Set Theory
Authors: Liang Zheng Li , Yang Xiao Wan
Published: September 2013

In reality, artificial factors are stronger in evaluating the comprehensive system during either the establishment of index system or the determination of the evaluation weight. In the paper it is discussed that rough set theory is applied to determine weight of comprehensive evaluation index, try to mine information from the data and to overcome the subjectivity of the weight setting in evaluating. We analyze a case using the designed program.
Simulation and Test of ASAC Dynamic Characteristic Based on ABAQUS
Authors: Sun Li Qin , Li Zhong Xing , Shen Xu Feng , Guo Ji Wei
Published: September 2013

Considering the influence factors of material nonlinearity ,geometric nonlinearity and etc.of air spring with auxiliary chamber in numerical calculations, implement method of airbag nonlinear characteristic ,gas unit, connecting pipe were defined. Finite element model was established in ABAQUS,and vertical characteristic simulation was carried out ,and the results shows that, system static stiffness reduces when increasing in the volume of the auxiliary chamber, but the change in stiffness is not is obvious when the volume increases to a certain degree, and static stiffness also reduces when initial pressure reducing. Simulation results are verified through characteristic test,and both are in good consistency.
Dynamics Simulation Analysis of Impact Mechanism in Impact Vibration Roller
Authors: Nie Guang Hua , Zhang Shuai , Du Xue Fang
Published: September 2013

the paper adopts dynamic simulation software ADAMS for establishing virtual prototype model, and dynamics simulation analysis study is conducted on the impact mechanism in order to better study the impact mechanism in impact vibration composite roller with round idler wheels. The kinematics features and dynamics features are studied. The theoretical curves of rail disk opening size and driving angular velocity is obtained. The rail disk structure is improved, and it is proved through software simulation that the improved mechanism is beneficial for improving the impact efficiency of the roller.
Simulation Analysis on Interior Flow Field of Recoil Brake Based on Dynamic Mesh
Authors: Sun Ye Zun , Qin Jun Qi , Di Chang Chun , Cui Kai Bo , Wang Yan
Published: September 2013

Recoil brake is one of the core components of the artillery. It plays a main buffer role in artillery firing. Its internal flow is very complex, so the traditional one-dimensional computational model can not reflect the characteristics of internal flow field fully and accurately. Two-dimensional computational model of the recoil brake with actual structure was proposed based on dynamic mesh technology. Using dynamic layering method, the movement of dynamic grid was driven by Profile file. The data of Profile file was obtained from experiment measured of artillery recoil. Simulation of the flow field of recoil brake accurately was achieved. Pressure, speed and other data were got by simulation. It also reveals the laws of liquid flow and can provide theoretical support for fault analysis and optimization design.
A Novel Particle Swarm Optimal Algorithm Hybridized with Random Disturbance Term
Authors: Zuo Yi , Chen Yong
Published: September 2013

Recently, Particle Swarm Optimization (PSO) has received increasing interest from the optimization community due to its simplicity in implementation and its high speed computational capability. However, traditional PSO has premature convergence problem. To prevent the premature convergence of PSO, some modified algorithms is proposed, based on these modified algorithms a novel hybrid algorithm with random disturbance is proposed in this paper. The performance of the proposed algorithm is testified on a suite of benchmark functions. The simulation results show that this hybridized PSO has great capability of preventing premature convergence and faster computing speed.
Multi-Objective Coverage Alogrithm for WSN Based on Particle Swarm Optimization
Authors: Jiao Yong Feng , Li Shuang Long , Bao Xi Rong
Published: September 2013

Probing in the energy-efficient coverage problem in Wireless Sensor Networks (WSN), a Discrete Multi-Objective Particle Swarm Optimization (DMOPSO) is proposed based on the characteristics of WSN. A multi-objective energy-efficient coverage strategy is established which focus on reduce the node utilization rate and ensure adequate coverage rate of the sensor networks at the same time based on the improved binary coding schemes. The proposed algorithm is used to solve the established multi-objective coverage problem. The effect of parameters on the optimization effect is analyzed and verified by algorithm analyses and simulations. Simulation result shows that the proposed method effectively reduced the node utilization while keep enough network coverage rate, which reduces network energy consumption and extends network life.
Delay Dependent H∞ Stochastic Stability Analysis for Stochastic Nonlinear Delay Hybrid Singular System
Authors: Lu Hong Qian , Liu Xing Ping , Zhou Wu Neng
Published: September 2013

This paper deals with the problem of stochastic stability analysis for stochastic nonlinear delay hybrid singular system in this paper. Based on linear matrix inequality approach, a delay dependent condition is proposed, which ensures the stochastic nonlinear delay hybrid singular system is stochastically stable with H performance under zero initial conditions. Finally, an example is provided to demonstrate the effectiveness of the proposed approach.
Image Quality Assessment Method for Underwater Acoustic Communication Based on Digital Watermarking
Authors: Ye Zheng Shan , Yuan Fei , Cheng En , Lin Cong Ren
Published: September 2013

This paper proposes a method of reduced-reference image quality assessment based on watermarking algorithm in underwater acoustic channel. By embedding the watermark image into the original one, then delivering the combined image through the channel distortion, the same channel distortion would be exposed to the original and the watermark image. In the receiver, we use the blind extraction methods to recover the watermark image and use the watermark degradation to evaluate the quality of the original one. In this paper, we build two kinds of channels: AWGN channel and Rice fading channel to validate the feasibility of the method which would be used in the underwater acoustic channel.
An Error-Reduced ADI-FDTD Algorithm in Debye Media
Authors: Fu Hui , Zhu Chuan Wen , Guo Gang , Wang Quan Min
Published: September 2013

The alternating direction implicit finite-difference time-domain (ADI-FDTD) method is an unconditionally stable numerical scheme, being proposed to remove stability limitations in conventional FDTD methods. Though the computation efficiency has been improved by ADI-FDTD, significant errors have been observed at large time steps. By compensating truncation errors, a low error ADI-FDTD method in Debye media is proposed based the ER(error reduced)-ADI-FDTD, complete three dimensional equations are derived. Simulation results are anlalyzed and compared with existing methods.
Construction of Motion Model of Motion Simulation System of Airport Fire Engine Simulator
Authors: Jia Li Shan , Wang Li Wen
Published: September 2013

To the high real-time quality requirement of motion simulation system of airport fire engine simulator, a simulation system with simplified motion model was promoted. The simplified motion model simplifies motion model of vehicle based on application requirement of virtual training of vehicle driving. On one hand, the simplification can reduce calculation amount of simulation, on the other hand, the simplification can make it easier to get parameters of model. Motion simulation system based on simplified motion model of airport fire engine was constructed and experiment was taken. Experiment showed that the motion simulation system has high calculation speed and good fidelity through setting parameters properly.
Indoor Localization Algorithm Research in Intelligent Lighting
Authors: Lai Sien , Shu Ting , Yang Guang Hui , Zhang Rui Lin
Published: September 2013

Due to existing indoor intelligent lighting system lack of the movement path predictionand the boundary of the space detection,thispaperpresents an idea to predict the location and distinguish the boundary of the space based on the historical data of someone's motion path; Indoor positioningisappliedtointelligent lighting system, according to the existing indoor localization algorithm, combined with the historical data of motion path, design an suitable algorithm for indoor intelligent lighting system, which can predict location and distinguish the boundary of the space.
Reversible Watermarking Algorithm in DFT Domain for 2D CAD Engineering Graphics
Authors: Jiang Xue Mei , Tu Xiao Li , Li Bo , Zhang Xiao Mei
Published: September 2013

In this paper, extract the coordinates of the vertices of the 2D CAD graphics to construct the complex-valued signal. And use the signal to do the DFT. The encrypted watermark is embedded into the DFT amplitude by using the IDE algorithm. Experimental results show that the algorithm has good invisibility, with good reversibility. The algorithm has robust against the attacks such as combination of translation, rotation, translation and adding an entity.
Design for the Township E-Government System Based on Wap and Web
Authors: Wang Chong Ying
Published: September 2013

This paper analyzes the importance of China's township-level e-government system and its functional requirements. According to the current China's national conditions, the authors proposed a program to develop e-government system for township based on Wap and Web. Then, the architecture diagram and topology diagram of township e-government system are given. At last, the functional modules of the system are described in detail.
DWMH: An Improved Algorithm Based on WM for Large-Scale Pattern Set
Authors: Xu Xiao Ning , Li Ai Ping , Zhu Jun Xing
Published: September 2013

String matching algorithm is one of the key technologies in numerous network security applications and systems. Nowadays, the increasing network bandwidth and pattern set size both call for high speed string matching algorithm for large-scale pattern set. An improved algorithm based on WM algorithm for large-scale pattern set is proposed in this paper. The presented multiple pattern string matching algorithm, DWMH, which we call in brief, combines the idea of Horspool algorithm with WM algorithm and applies the method of double hash to revise WMs HASH table to achieve better performance. Our extensive experiments demonstrated that DWMH algorithm is more efficient than WM algorithm, particularly when the size of pattern set becomes large-scale.
A Novel Collaborative Filtering Recommendation Approach Based on Field Authorities
Authors: Xue Zhi , Zhang Yao Xue , Zhou Yue Zhi , Hu Wei
Published: September 2013

This paper presents a novel collaborative filtering recommendation algorithm based on field authorities which simulates the real life word of mouth recommendation mode. It uses the specialistic knowledge from field authorities of different genres, and successfully addresses data sparsity and noise problems existing in traditional collaborative filtering. Meanwhile it also improves prediction accuracy and saves computational overhead effectively. Experiments on MovieLens datasets show that the accuracy of our algorithm is significantly higher than collaborative filtering approach based on experts, and has larger scope because of no external data limitations. Meanwhile, compared to traditional k-NN collaborative filtering, our algorithm has a better performance both in MAE and precision experiments, and the computational overhead has a decrease of 19.2% while they provide the same accuracy level.
Maximum Power Point Tracking Based on Look Up Table Approach
Authors: Malathy S. , Ramaprabha R.
Published: September 2013

This work proposes a lookup table based approach to track the maximum power from a solar photovoltaic (PV) module. The performance of the solar PV module is greatly influenced by various environmental factors and it is therefore necessary to operate the PV module at its optimal point so as to ensure that maximum power is extracted from the PV source. Several fixed step and variable step maximum power point tracking (MPPT) algorithms have been proposed in the literature. In this paper a simple and fast maximum power tracking method based on lookup table approach is proposed. The maximum power point voltages for various insolation levels are obtained from the experimental setup and are fed to the look up table. This look up table thus formulated can then provide the reference voltage for various insolation conditions without many computations. The performance of the proposed method is compared with that of the conventional MPPT methods like perturb and Observe (P&O), Incremental Conductance (INC) and Fuzzy logic (FLC) based MPPT. The simulation results show that the lookup table (LUT) approach tracks the maximum power point faster than the conventional algorithms under changing illumination conditions and reduces simulation time.
Performance Improvement on a Single Cylinder Diesel Engine Powered with Pongamia Biodiesel by Incorporating Swirling Grooves
Authors: Lalvani J. Isaac Joshua Ramesh , Parthasarathy M. , Arunkumar A.V. , Annamalai K.
Published: September 2013

The motive of the experimentation is to improve the combustion of the direct injection diesel engine powered with biodiesel blend. Initial experimentation was made with the diesel in a conventional unmodified diesel engine. By careful literature survey and technical reviews 20% blend of Pongamia biodiesel with 80% of diesel (B20) had been taken as a test fuel. The swirl motion inside combustion chamber is increased by means of providing the swirling grooves over the piston crown with constant depth 2 mm and variable width of 5.5mm, 6.5 mm and 7.5 mm, unless the previous work done by researches the care has been taken to maintain the compression ratio of the engine. Among the various configurations, the swirling grooves of depth 2mm and width 6.5 mm showed the increase in brake thermal efficiency up to 11 % and decreasing trends in hydrocarbon, carbon monoxide, and smoke emissions. Thus the findings of the present work showed the increase in performance and reduction in the emission of the direct injection diesel engine fuelled with Pongamia biodiesel blend.
Analysis and Experimentation of a Three Phase Asymmetric Cascaded Multilevel Inverter for Electric Vehicles
Authors: Seyezhai R. , Sree K. Radha , Sivapathi K. , Vardhaman V.
Published: September 2013

Multilevel inverters have been gaining immense popularity in high power applications such as Electric vehicles, Flexible AC Transmission Systems etc. This paper focuses on an asymmetric cascaded multilevel inverter employing the variable frequency carrier phase shifted PWM technique. The major advantage of this strategy is that it aids in balancing the switch utilization. The proposed strategy was found to have lower THD and switching losses when compared to the conventional strategies. The simulation was performed using MATLAB/Simulink and the results were verified experimentally.
Investigations on the Effect of Bio Fuel Enhancer Additive with Cashew Nut Shell Liquid Biodiesel Blends on Engine Performance and Pollutant Emissions in a Diesel Engine
Authors: Pushparaj T. , Lalithmuneendirakumar C. , Ramabalan S.
Published: September 2013

The purpose of this study is to investigate the impact of bio fuel enhancer additive added to 20% cashew nut shell liquid (CNSL) biodiesel blended with No.2 diesel fuel, in terms of the performance and exhaust emissions on a 4-cylinder naturally-aspirated direct-injection diesel engine. Experiments were conducted under five engine loads at a steady speed of 1500 rpm. The influence of blends on carbon monoxide (CO), nitrogen oxide (NO), carbon dioxide (CO2), hydrocarbon emission and smoke opacity were investigated. . The experimental results showed that the bio fuel enhancer additive improves the performance parameters and decreases CO emission by 13% and HC emission by 15% as compared to biodiesel. Bio Fuel Enhancer (BFE) additive reduces the NO emission remarkably by 55% as compared to biodiesel.
Nonlinear Unbalanced Load Compensation for PV Sourced Grid Connected Inverter
Authors: Sivakumar P. , Jeevitha M.
Published: September 2013

The major problem in the PV system is the poor PV consumption under viable irradiation condition. So in order to improve the power consumption of PV along with grid connected inverter, this system has been implemented with controller analysis and model. This system is mainly used for non linear load compensation under unbalanced condition. In the existing method, Peak current of the inverter is reduced during the unbalanced grid-voltage sags with the help of current harmonics injection which increases the total harmonic distortion. Double synchronous reference frame technique with PLL is used to synchronize PV with grid. As well as the maximum power point of PV is tracked using Incremental Conductance technique to reduce the error and improves the system efficiency. Selected simulation results using MATLAB/Simulink are reported in order to show the proposed system efficient.
Harmonic and Power Factor Analysis with Reactor and Capacitor in Adjustable Speed Drive
Authors: Srinivasan M. , Praba S.U. , Suganthi R.
Published: September 2013

Ac line reactor, Dc link reactors and shunt capacitors are mostly used for improving the power factor and reducing the THD level in the adjustable speed drive (ASD) and protecting the device from other power quality problem. The effectiveness of these reactors are affected by many other factors such as loading and source impedance. Under variable load conditions such factors are analyzed and performance of system also analyzed. In this paper simulation is done by inserting such factor which also suggested for future real time applications.
A Novel Control Strategy for DVR to Improve Voltage Profile in Wind Farm
Authors: Himaja M. Naga , Premalatha S. , Dash Subhransu Sekhar , Babu Paduchuri Chandra
Published: September 2013

Power quality is one of major concerns in the present era. It has become important, especially, with the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply. To improve the power quality, custom power devices are used. The device considered in this work is DVR. This work presents a control strategy for a DVR to improve the stability in wind farms based on SCIG. The DVR controller is designed to work under unbalanced conditions, which allows overcoming most faults in the power grid. The proposed strategy is capable of balancing voltages at wind farm terminals obtaining several advantages. Firstly, negative-sequence currents are eliminated; thus, overheating, loss of performance, and decreasing of generator useful life are avoided. Secondly, by nullifying negative sequence voltages, 2ω pulsation in the mechanical torque is prevented, reducing high stress in the turbine mechanical system, especially in the gearbox. The power system, DVR converter, and controller were implemented in the Sim power Systems blockset of SIMULINK/MATLAB®.
Comparative Analysis of Solution Methods to Power Electronic Interface Modeling for Renewable Energy Applications
Authors: Randhir D. , Umashankar S. , Vijayakumar D. , Kothari D.P.
Published: September 2013

This paper presents the comparison between various numerical methods namely Euler's Method, Midpoint Method, 2nd order Runge Kutta Method and 4th order Runge Kutta Method with the analytical method to solve a power electronic system in both single phase and three phase configuration using decoupled methodology. The values of source current, load current and DC link voltage are obtained for each method using Matlab software and compared with each other. Also, the error in each numerical method with respect to analytical method is calculated and tabulated. These power electronic models could be an excellent research platform for testing the renewable energy systems without going for full scale or scaled down models.
Thermal Influences on Deep Drawing Process of Ferritic and Metastable Austenitic Stainless Steels
Authors: Schmid Philipp
Published: September 2013

Sheet metal forming processes, in particular deep drawing processes, are highly influenced by occurrence of latent and friction heat. Especially when forming metastable austenitic stainless steels, strain-induced martensite formation is suppressed by higher temperatures and therefore influences the material behavior and so called TRIP-effect. This study gives an overview about thermal influences on the deep drawing forming process of metastable austenitic CrNi-steel 1.4301 in comparison with ferritic stainless steels such as 1.4016. Measurements on serial and evaluation tools were carried out to determine occurring temperatures within forming tools. Attention is paid to effects on tribological aspects such as behavior of lubricants at higher temperatures, influence of temperature development on the martensite formation, mechanical properties, forming limit curves as well as heat flow within the forming tools. Lubricants with different temperature stability were compared to each other with determination of friction coefficient in strip drawing tests. Martensite and temperature development during forming of material was measured in non-isothermal tensile tests approving a high dependency of martensite formation on temperature. Forming limit curves for temperatures determined from RT to 140°C for EN 1.4301 are showing high dependency of necking behavior especially under plain strain conditions. Determination of thermal contact conductance coefficients for process and tool relevant material combinations allows interpreting heat flow mechanisms in forming tools and improving forming process to higher robustness. Results of this paper can be used to individually set boundary conditions for thermo-mechanical coupled forming simulation of austenitic stainless steel and process layout of tool temperature control systems.
Integrated Diagnostic and Preload Control for Ball Screw Drives by Means of Self-Sensing Actuators
Authors: Ehrmann Christopher , Herder Stefan
Published: September 2013

Piezoelectric ceramics can be used as sensors, as well as actors. The concept of a self- sensing-actuator tries to use both modes of operation in one device, allowing the economic integration of mechatronic systems. Possible fields of application are ball screws of machine tools, where wear-induced degradation of the preload can be compensated. Furthermore, the signal processing part of such a system can be used to gather information related to the condition of the ball screw. Both excitation signal generation and filtering of the measured signal have to offer high flexibility and signal fidelity. In this article the concept of a power amplifier and its corresponding signal processing system are presented.
The Specific Heat Jump of Hybridized Two-Band Superconductor
Authors: Seechumsang J. , Chanpoom T. , Chantrapakajee S. , Udomsamuthirun Pongkaew
Published: September 2013

The specific heat jump of the two-band hybridized superconductor was studied. The two-band model is consist of conduction electron band and other-electron band with the upper and lower band of quasi-particle energy spectra occurred by hybridization. The specific heat jump was determined by making the assumption that the conduction electron band having the same energy as other-electron band, and the other-electron band having the energy near the Fermi energy. The analytic formula of specific heat jump of the two-band hybridized superconductor was derived and the effect of hybridization coefficient on the specific heat jump was investigated.
Fabrication and Characterization of Antibacterial Ag-TiO2 Thin Films Prepared by DC Magnetron Co-Sputtering Technique
Authors: Sornsanit K. , Horprathum M. , Chananonnawathorn C. , Eiamchai P. , Limwichean S. , Aiempanakit K. , Kaewkhao Jakrapong
Published: September 2013

In this study, silver-doped titanium dioxide (Ag-TiO2) thin films were prepared co-sputtering technique in order to promote photo-induced antibacterial applications. The high-purity Ag (99.995%) and Ti (99.995%) were simultaneously co-sputtering on BK7 glass and silicon (100) wafers substrate. The structure, morphology, surface roughness and optical properties were characterized by grazing-incidence X-ray diffraction (GIXRD), field-emission scanning electron microscopy (FE-SEM) and UV-Vis spectrophotometer, respectively. The results showed that the as-deposited Ag-TiO2 thin films had high transparency in the visible range. The antibacterial activity was studied in the presence and in the absence of UV irradiation against Escherichia coli as a model for Gram-negative bacteria. The results indicated that, in comparison to conventional TiO2 films, the Ag-TiO2 thin films exhibited excellent antibacterial properties under the UV illumination.
Sintering, Microstructure and Electrical Properties of MnO2 and CuO-Doped [Na0.515K0.485]0.94Li0.06(Nb0.99Ta0.01)O3 Ceramics
Authors: Bomlai Pornsuda
Published: September 2013

Ceramics with formula (1-x-y)[Na0.515K0.485]0.94Li0.06(Nb0.99Ta0.01)O3 (NKLNT) xMnO2yCuO (when x, y = 0, 0.005 and 0.01) were prepared by a reaction sintering method. The effects of doping level on sinterability and properties of NKLNT ceramics were studied. The results indicated that the co-doping of MnO2 and CuO was effective in promoting the densification of ceramics. Grain growth during secondary recrystallization was also affected, leading to larger grain size with x, y = 0.01 sample. X-ray diffraction data showed that the orthorhombic tetragonal morphotropic phase boundary existed in all the samples. At room temperature, the dielectric properties of NKLNT ceramics were improved by doping of appropriate MnO2 and CuO content. The temperature dependence of dielectric constant showed a decrease slightly in Curie temperature (TC) with increasing MnO2 and CuO content. The composition with x = 0.005, y = 0 exhibited favorable properties for the promising lead-free piezoelectric candidate material.
The Preparation and Characterization of Y145 Superconductor
Authors: Chainok P. , Sujinnapram Supphadate , Nilkamjon T. , Ratreng S. , Kritcharoen K. , Butsingkorn P. , Ruttanaraksa P. , Udomsamuthirun Pongkaew
Published: September 2013

In this research, we synthesized and characterized the physical properties of YBa2Cu3Ox (Y123) and YBa4Cu5Ox (Y145) superconductors by solid state reaction and melt process. The raw materials Y2O3, BaCO3 and CuO were mixed, ground and react in the air atmosphere at 950 °C, at 980 °C for solid state reaction and melt process, respectively. The samples obtained were characterized by the resistivity measurement, SEM, EDX, XRD and DTA. It was found that the critical temperature onset of Y145 is 94 K and 96 K for solid state reaction and melt process, respectively. The samples were inhomogeneous with no impurity. The crystal structures was orthorhombic which a = 3.80446 Å, b = 3.86474 Å and c = 19.37104 Å for Y145 solid state reaction and a = 3.80180 Å, b = 3.86483 Å and c = 19.38194 Å for melt process. The peritectic temperature of Y145 is 1018 °C.
Effects of Thermal and Cross-Track Variations for Longitudinal Heat-Assisted Magnetic Recording Systems
Authors: Kovintavewat Piya , Kaewpukdee Adisorn , Chirdchoo Nitthita
Published: September 2013

The current data recording technology is approaching its capacity limit approximately 1 Tbit/in2(terabits per square inch) known as superparamagnetic limit. Heat-assisted magnetic recording (HAMR) is one of the promising technologies that is being planned to be used as a new data recording technology to achieve the storage capacity beyond 1 Tbit/in2. In HAMR, the laser is applied to heat a magnetic medium during the writing process, which results in the unique transition characteristics if compared to a conventional system. This paper investigates the effects of thermal and cross-track variations to the transition characteristics (both transition center and transition parameter) of longitudinal HAMR systems. Experimental results indicate that the longitudinal HAMR system can withstand some amount of thermal and cross-track variations and still provides satisfactory system performance.
Visible Luminescence of Pr3+ in Bismuth Borate Glasses
Authors: Chanthima Natthakridta , Boonin Kitipun , Limsuwan Pichet , Kaewkhao Jakrapong
Published: September 2013

Visible luminescence of Pr3+ ions in bismuth borate glasses doped with difference concentration of Pr2O3 have been studies. The glasses of composition 30Bi2O3 : (70-x)B2O3 : xPr2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) were prepared by the melt quenching technique. The spectral properties were investigated using the absorption and emission measurement. These glasses have shown emission and excitation bands in visible region. The emission band of Pr3+ doped glass centered at 600 nm (1D23H4), 642 nm (3P03F2) and 704 nm (3P03F3) have been observed with 469 nm (3H43P1) excitation wavelength. The excitation band revealed centered at 447, 469 and 482 nm corresponding to the 3H43P2, 3P1 and 3P0 transitions, respectively.
Design and Synthesis of Ruthenium (II) Complexes and their Applications in Dye Sensitized Solar Cells (DSSCs)
Authors: Prompan Preeyapat , Wongkhan Kittiya , Jitchati Rukkiat
Published: September 2013

Three thiocyanate-free ruthenium (II) sensitizers, [RuII(dcppy)(L1-L3)](PF6)] where dcppy = 4, 4-dicarboxylic acid-2, 2-bipyridine, L1 = 2-(2,4-difluorophenyl)-5-(trifluoromethyl) pyridine, L2 = 2-(2,4-difluorophenyl) pyridine and L3 = 2-phenyl-5-(trifluoromethyl) pyridine were synthesized and applied for dye-sensitized solar cells (DSSCs). The structures of ruthenium complexes were characterized by 1H, 13C NMR and IR spectra. The absorption was studied by UV-Vis spectroscopy and the electrochemical property was determined by cyclic voltammetry. The surface morphology of ruthenium complexes on mica was examined by atomic force microscopy. The performance of this complexes as photosensitizer in TiO2 based dye sensitized solar cells is studied under standard AM 1.5 sunlight and by using an electrolyte.
Preparation and Adsorption Property of Nano-Rods Hydroxyapatite Using Cationic Surfactant Templates
Authors: Wang Shao Hong , Xia Jian Guo , Wang Mei Han , Hou Zhao Xia , Zhou Dan , Zhou Li Di
Published: September 2013

Nano-rods hydroxyapatite (HA) was synthesized by hydrothermal method using Ca(NO3)2·4H2O and H3PO4as precursors and cationic surfactant (CTAB) as a template. The effect of pH value and reaction temperature on the phase and morphology of HA were investigated. HA samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that high pH values resulted in high purity of HA. HA morphology changed from irregular round shape to nano-rod shape with the increase of the reaction temperature from 80°C to 120°C. The prepared HA was utilized as adsorbent to remove copper ion from aqueous solution. The adsorption results showed that nano-rod HA had a rapid Cu2+adsorption rate and good removal efficiency (>99%).
The Energy and Environmental Performance of a Project Using Solar Hot Water System with Vacuum Tube Materials
Authors: Hu Zu Shan , Yao Jian
Published: September 2013

This paper calculates the energy and environmental performance of a project with solar hot water system using solar hot water system with vacuum tube materials. The results show that solar hot water application in buildings not only saves energy consumption but also reduces carbon emissions, and the dynamic payback period is about 12 years. Thus solar hot water system should be widely used in buildings in China.
Aspheric Surface NC Polishing Force-Position Decoupling Control Technology
Authors: Li Guo Fa , Shan Cui Yun , Zhao Pu
Published: September 2013

Based on MTTSD (Magneto-rheological Torque Transmission Servo Devices) and force-position decoupling control technology, an aspheric surface NC polishing project is put forward. The aspheric surface polishing fundamental theory is researched. Under the condition of a constant material removal rate, a new aspheric surface polishing model is brought forward. In addition, under the condition of a constant material removal rate, this paper brought up a polishing force control model and a workpiece rotating speed control model, according to witch, force and rotating speed change with the coordinates of working points, and variation curves are drawn.CLC Number: TH166 Document Identifier: A
Study on the Influence of Organic Fiber and SBR Latex on the Bending Properties of Rubber Mortar
Authors: Ruan Shao Qin , Jiang Si Xian , Wei Lai
Published: September 2013

This paper deals with the investigation of the bending properties of rubber mortar with the inclusion of SBRL (butylbenzene latex) and PP (polypropylene) fiber. The results proved the elasticity modulus of modified mortar decreased, especially when modified materials groups were SBRL10 %+R30%+PP, the elasticity modulus of mortar was minimum and the flexibility was the best. The deflection increased with the inclusion of modified materials, especially when 30 vol.% of rubber was included in mortar. The specimens containing 20 vol.% of rubber exhibited post failure loads and the peak load of polypropylene fiber and SBR latex modified rubber mortar with 20 vol.% of rubber grew, whether specimens were included with polypropylene fiber or not.
Study on the Influence of Polypropylene Fiber and SBR Latex on the Mechanical Properties of Rubber Mortar and Microstructures Analyzed
Authors: Ruan Shao Qin , Jiang Hong Wei , Yin Yin
Published: September 2013

This paper presents a study on the mechanical properties of rubber mortar with the inclusion SBRL (butylbenzene latex) and PP (polypropylene) fiber and the microstructures of SBR latex modified mortar were analyzed. The results proved for specimens with 20 vol.% of rubber, when the P/C of SBR latex was 10%, the compressive and flexural strength of SBR latex modified rubber mortar was optimal. Besides, for specimens with 20 vol.% of rubber, the compressive and flexural strength of SBR latex and polypropylene fiber modified rubber mortar increased with the inclusion of polypropylene fiber, especially when the P/C of SBR latex was 10%. Through scanning electron microscope (SEM), it was founded that polymer has formed a consecutive reticulate film which has a toughening effect on cement matrix.
The Role of Building Materials Development in Constructing Form Evolution
Authors: Sun Shi Cun , Wei Ze Song
Published: September 2013

The study of building form is complicated and multifaceted, of which,tectonic approach has been becoming one of the important research directions.Simultaneously, the development of construction materials is also representedthrough diversified and rich architecture form. The paper focuses on how building materials affect architecture form and ultimately is reflected in our academic design and daily life, how the development of construction materials in the history and at present influences the tectonic form, and whether it is feasible to introduce the element of construction materials into architectural appraisal.
Pyrolysis Kinetics Equation of Larch Bark
Authors: Du Hong Shuang , Li Xiang Yu , Ren Xue Yong , Han Yan Xue
Published: September 2013

The larch bark was examined by non-isothermal means to determine the mass loss kinetics of the thermal decomposition with linear temperature programming in nitrogen atmosphere. In this work, mechanism equation of = was used for Coats-Redfern integral method at the different heating rates. The apparent activation energy, pre-exponential factor and the pyrolysis kinetic equations at the different heating rates were obtained. The pyrolysis temperature area was divided into two separate temperature regions for the pyrolysis kinetic equation and the two components were decomposed respectively at the two separate temperature regions. The global mass loss rate of the bark is considered as controlled respectively by the reactions of the two components respectively during the lower and higher temperature ranges. The kinetics of the two components are found to abide by the mechanism equation of =, which gave the best fits to the experimental data. The obtained kinetic equations of the bark at the different heating rates were additionally validated by the reasonable agreement between the experimental and calculated results.