bluuebunny/crossref_metadata_2025 huggingface dataset:
Static and Fatigue Strengths of Carbon Nanotube/Epoxy Composites under Hygrothermal Environments
Authors: Jen Yi Ming , Huang Chien Yang
Published: March 2013

This study experimentally analyzed the hygrothermal effect on the static and fatigue strengths of acid-treated multi-walled carbon nanotubes (CNTs)/epoxy composites. The nanocomposite specimens with various CNT contents (0., 0.5, and 1.0 wt.%) were statically and fatigue-tested under three different hygrothermal conditions (25 °C/60% RH, 25° C/85% RH, and 40 °C/85% RH) to investigate the influences of hygrothermal conditions and CNT contents on the tensile static and fatigue strengths of the studied nanocomposites. The results show that the static and fatigue strengths decreased slightly at 25 °C/85% RH environments compared with those tested under the 25 °C/60% RH condition. However, the static and fatigue strengths of the studied nanocomposites decreased substantially under the 40 °C/85% RH condition. The combined temperature and humidity environments weaken the interfacial adhesion between the CNT surfaces and the epoxy matrix. Moreover, the experimental results show that the addition of 0.5 wt.% of carbon nanotubes improved the static and fatigue strengths considerably under the same hygrothermal environments. However, when an excessive amount of CNTs was used (1.0 wt.%), the nanocomposite exhibited the lowest strengths compared with the specimens with 0 and 0.5 wt.% CNTs. The stress concentration effect caused by the CNT aggregates was detrimental to the static and fatigue strengths of the studied nanocomposites.
Energy Efficient Sensor Configuration by Fishing Spider Inspired Mechanism
Authors: Lee Kyu Hong , Lee Hee Sang
Published: March 2013

Wireless sensor networks have inherent characteristics that differ from other wireless networks. Therefore, topology configuration and routing methods in WSNs must address these characteristics. In this paper, we propose an energy efficient clustering model. This model was inspired by the behaviors and capabilities of the six-spotted fishing spider, Dolomedes triton. The suggested model performs cluster-heads selection and clustering in self-organized ways. In order to determine the cluster-heads and the cluster-members, each sensor node uses the local information and simple rules that have been inspired by the Dolomedes triton. We compared our model with a well-known cluster-based routing protocol that uses random fairness for the selection of sensor node cluster-heads. In our computational experiments, we have showed that the energy efficiency and lifetimes of our bio-inspired model exceeds those of the comparison protocol by only using simple bio-inspired mechanism. We also demonstrate our model’s good performance in terms of scalability, which is one of the important indicators of performance for self-organized wireless sensor networks.
Estimation of Occluded Lower Limb Using Inverted Pendulum Model
Authors: Tenn Hian Kun , Tsai Yao Yang
Published: March 2013

For many interactive vision based systems, users are captured by the system and modeled as a simplified skeleton. The skeleton model usually encounter problems of occlusion because of obstacles or other users appearing in the environment. In this paper, we proposed a method based on an inverted pendulum model (IPM), which was applied to recover the occluded leg of skeleton model. The skeleton model was provided by Vicon motion measurement system, which captured the participant's motions. One leg of the skeleton model was removed intentionally and the proposed method was used to estimate the pose of the occluded leg in real-time. The results showed that most of the positioning errors were within 10 cm on average and the processing rate exceeded 100 fps.
Implementation of Lane Departure Warning System Based on Machine Vision
Authors: Sheu Jia Shing , Chu Hao , Liu Chun Chi
Published: March 2013

Purpose of this paper raise a vehicle lane departure warning system based on the machine vision. It does not need to use the parameters of the camera which do the road marking recognition system installed in the interior of the camera by algorithms. Regarding the time line of the intelligent transport system, it is to solve the various problems possibly arising from driving on the road. This system is mainly for the warning of the unexpected departure of vehicle. The method is to use the digital camera to capture continuous images and identify the vehicle moving direction by the detection of the left and right markings, as well as forecast the driving direction of the vehicle for the reference of vehicle departure warning. In this paper, the used algorithms include brightness adjustment, binarization, dilation, erosion, and edge detection image processing techniques.
Windshield Warning System for Intelligent Vehicles
Authors: Lin Chyi Yeu , Jiang Jinn Feng , Chen Yi Jie , Wei Hung Yuan , Wang Cheng Hsien
Published: March 2013

The present study proposes a windshield warning system for vehicles that marks potential hazardous objects in front via marks on the windshield. The target is identified by the camera and the software system and then used to construct the line-of-sight equation based on the coordinate system of the moving vehicle. The explicit equation of the intersection point of the line of sight and the windshield surface is derived using an algebraic method. A warning mark is then projected at the intersection point on the windshield by a two-degree-of-freedom laser projector, allowing the driver to easily identify the obstacle. The feasibility of the proposed system was verified using an actual vehicle. Results show that the system can perform the required function in real time.
Study on Multi-Stage Cold Forging of Stainless Automotive Battery Fastener
Authors: Sun Ming Chao , Tzou Gow Yi , Zheng Liang An
Published: March 2013

Stainless automotive battery fastener requires high dimension precision and narrow tolerance. In order to save the developing cost and accumulate more production design experiences, CAD/CAE technology has been used in multi-stage cold forging with five stages to shorten our developing cycle time. In this paper, the CAD drawing is made by Inventor 3D software, then import the STL file to DEFORM-3D software to do the settings of pre-process and simulation analysis. Effective stress, effective strain, velocity field, and forging force have been shown in this study. Finally, the actual manufacture measurement results compares with simulation datum to verify the analysis acceptance. After comparing the FEM simulation results with actual forming measurements, the error rate of washer diameter is increased in fourth stage. Although the measurement results are still in tolerance, the future work is to decrease the error rate through optimizing the mold design of fourth stage. The verification is performed to reduce the error rate according to the research method proposed in the study. On the other hand, the mold life in the actual forming is found to be easily damaged in the fifth stage. In the future, production improvement should be done through modifying the design of mold and die for the third and the fourth stages, the life of mold and die is explored to reduce the forging force in the fifth stage.
Robot Simultaneous Localization and Mapping Using Speeded-Up Robust Features
Authors: Wang Yin Tien , Chi Chen Tung , Feng Ying Chieh
Published: March 2013

An algorithm for robot mapping is proposed in this paper using the method of speeded-up robust features (SURF). Since SURFs are scale- and orientation-invariant features, they have higher repeatability than that of the features obtained by other detection methods. Even in the cases of using moving camera, the SURF method can robustly extract the features from image sequences. Therefore, SURFs are suitable to be utilized as the map features in visual simultaneous localization and mapping (SLAM). In this article, the procedures of detection and matching of the SURF method are modified to improve the image processing speed and feature recognition rate. The sparse representation of SURF is also utilized to describe the environmental map in SLAM tasks. The purpose is to reduce the computation complexity in state estimation using extended Kalman filter (EKF). The EKF SLAM with SURF-based map is developed and implemented on a binocular vision system. The integrated system has been successfully validated to fulfill the basic capabilities of SLAM system.
Multi-View 3D Object Reconstruction Using Coordinate Transformation
Authors: Park Ji Hun
Published: March 2013

The algorithm presented in this paper takes at least two images taken by an ordinary digital camera, computes camera parameters and outputs scene geometric information. The method takes at least one right-angle triangle in the scene, install a local coordinate at each triangle, and compute camera parameters by using the local coordinate transformation. The algorithm computes orientations and displacement relationships among the triangles in the scene while correcting the previously computed camera parameter values. In order to find optimal solution, we set optimization variables as camera calibration parameters and coordinate transformation values between local coordinates. The background eliminated images and calculated camera parameters allow us to reconstruct a 3D target object in VRML. The merit of this algorithm is in handling varying focal camera, in easy initial guessing value computation and in using fewer feature points compared to Zhang’s calibration method.
Low Luminance Dynamic Range Converter for Vehicle Application
Authors: Fan Yu Cheng , Shen Jan Hung
Published: March 2013

This paper presents a low luminance dynamic range converter that includes light recording and adjustment system for vehicle application under light insufficient environment. The development of vehicle electronic technology has improved traditional vehicle function. How to design a safety function system for vehicle become more and more important in vehicle industries. This work designs low luminance dynamic range converter circuit for vehicle application and provides a safety-driving environment. In the proposed method, we adopt video capture system to record light information from driving environment. An adaptive adjustment is adopted to re-arrange the histogram according to the distribution of luminance. Then, we use a series of test images and extract the characteristic value to train the system to reflect practical circumstances. Next, color calibrations and de-noise processing are performed to improve the visual quality. The presented approach considers the realistic driving situation and provides a bright and safe visual environment for driver under light insufficient environment.
A Novel and Experimental Design for Mechanical Ventilation with Optimal Spontaneous Flow Pattern and WOB Feedback Control
Authors: Lin Shyan Lung , Hung San Shan , Chen Ching Kun , Chang Hsing Cheng
Published: March 2013

In this study, we proposed an innovative design for mechanical ventilation by applying the previously implemented optimal respiratory control simulator as the controller of an experimental ventilation device. Instead of providing a fixed airflow pattern, an optimal spontaneous flow pattern was optimized by the simulator based on patient’s estimated respiratory mechanics and was applied to drive a ventilation device. We also implemented an experimental ventilation control system, including the simulator, a ventilation device, an artificial lung, and a feedback control mechanism to attain minimum work of breathing during mechanical ventilation. The experiments were elaborated to verify that once patient’s respiratory physiology was significant changed, the breathing signals and measured respiratory mechanics were instantaneously monitored, and the optimization process was renewed by the simulator under the feedback control strategy.
A Novel Hybrid Recurrent Wavelet Neural Network Control for a PMSM Driven Electric Scooter
Authors: Lin Chih Hong , Lin Chih Peng
Published: March 2013

The electric scooter with nonlinear friction force of the transmission belt made the hybrid recurrent neural network (HRNN) control system with degenerated tracking responses. In order to overcome this problem, a hybrid recurrent wavelet neural network (HRWNN) control system is proposed to control for a permanent magnet synchronous motor (PMSM) driven electric scooter. The HRWNN control system consists of a supervisor control, a RWNN and a compensated control with adaptive law. The on-line parameter training methodology of the RWNN can be derived using adaptation laws and the Lyapunov stability theorem. The RWNN has the on-line learning ability to respond to the system’s nonlinear and time-varying behaviors. To show the effectiveness of the proposed controller, comparative studies with HRNN control system is demonstrated by experimental results.
Adaptive Single-Neuron Proportional-Integral-Derivative Controller Based on Memristor
Authors: Fang Xiao Yan , Wang Li Dan , Duan Shu Kai
Published: March 2013

The traditional proportional-integral-derivative (PID) controllers are still the most popular controllers in the majority of manufacturing industries. However, its control parameters are difficult to regulate with the environment changing. The resistance value of the memristor dynamically depends on its charge and flux changing, which can be regarded as a tunable parameter element in the modern control system. In this paper the newest circuit element is applied to replace the synapse weight and realize self-regulation of PID controller parameters with the environment changes in the control network. It is possessed of many characteristics such as simple structure, good robustness, high reliability and adaption to the changing environment. Then the position tracking curves and parameter varying curves are obtained by experimental simulation according to the different learning rules. The experimental simulation results show that the memristive PID control network can realize on-line control and identification with higher control reliability and better adaptability.
An Intelligent Garbage Can Decision-Making Model Evolution Algorithm on Optimal Design of Fuzzy Controller of Intelligent Lighting Systems
Authors: Lin Ching Hai , Kuo Hsin Chuan , Lee Chao Tsung
Published: March 2013

In this paper, an intelligent garbage can model-based differential evolution algorithm (IGCMDE) is proposed to simulate human social organization by its population system, based on the differential evolution algorithms (DEs) and the logical framework of the garbage can decision model with group meeting. When faced with issues such as unclear goals and technologies, participators turnover, etc., representatives of all participating parties will communicate, argue, compromise and adapt with each other, in order to find a solution to the problems. Group meetings are conducted to choose the best solution in a more objective, reasonable and efficient way. At last, we used IGCMDE to optimize the fuzzy controller with fuzzy logic control theory. We present a method for daylight blending control with two novel contributions: 1) smart luminance sensing; 2) daylight luminance control. The proposed method was implemented as an intelligent lighting system in a parking tower environment. The result demonstrated that IGCMDE possesses an excellent search performance and the intelligent lighting system showed significant energy savings.
Delayed State Feedback Control for Singular Plants with Device Delay
Authors: Lee Ching Min , Huang Jhih Hong
Published: March 2013

In this paper, an H∞ state feedback control problem for a discrete–time singular plant with device delay is considered. The device delay often appears in computer based control systems, networked circuits systems, communication systems, process control systems and so on. And the state feedback control law is supposed to include possible time varying transmission delay within an interval. In this case, we derive a set of LMI-based sufficient conditions for the analysis and the delayed controller synthesis problems, respectively, via a finite sum inequality approach. In order to show the efficiency of the proposed method, a numerical example is presented at the end of this paper.
Real-Time Breakthrough Detection for Laser Drilling Based on Coaxial Visual Sensing Technology
Authors: Ho Chao Ching , Hsu Jin Chen , Chang Yuan Jen , Kuo Chia Lung , He Jun Jia
Published: March 2013

As the production demand for laser drilled holes continues to grow, efficient and reliable process monitoring and control techniques are required in order to improve the manufacturing efficiency and reduce manufacturing cost for ensuring quality conformance. A robust, real-time monitoring system for breakthrough and the drilling depth detection in laser drilling is proposed. The system is based on based on coaxial visual sensing technology of the working surface using a CMOS camera, coupled with microcontroller control of the drilling laser operation. The camera is installed adjacent to the entry surface of the workpiece, and the spatial extend of the laser-induced plasma at the working site is monitored as the criterion for breakthrough detection. Therefore, on-line inspection system with low cost is developed to increase productivity. Experimental results show that the proposed system successfully detects when the laser beam has broken through a workpiece, and turns off the laser automatically by feedback control.
Remote Filter Design for Discrete Singular Systems
Authors: Lee Ching Min , Chiu Wei Cheng
Published: March 2013

In this paper, a remote filter design problem for a discrete-time singular plant under a networked control system is investigated. For a remote system, it is natural that transmitted signals have some delayed phenomenon and some data losing due to heavy loaded networks or under unreliable communication envelopment. In this case, a Bernoulli random distributed sequence is introduced to model the possible data losing, as well as the working but delayed transmitted signals are limited in some time interval. Applying a finite sum inequality approach, a set of delay dependent sufficient conditions for the admissibility analysis and the filter design problems are derived under an LMI framework. In order to verify and show the efficiency of the proposed method for such problem formulation, a numerical example is presented at the end of this paper.
Research on the Fuzzy PID Controller Based on PLC Applied in the Cold Pellet Production
Authors: Xiong Man Chen , Wang Ling Long , Jiang Yi Heng
Published: March 2013

Parameter self-setting fuzzy PID control algorithm for control drying temperature is proposed to improve the problem about big fluctuations in temperature and high pellet broken rate of traditional control on Cold pressure ball drying system in this paper, and the controller create intelligence temperature control system through combine fuzzy control and PID control. We establish fuzzy controller, preparation of fuzzy look-up table in PLC and combined with PID control module to realize fuzzy PID control algorithm, through the computer simulation to analyze the fuzzy PID controller control effect.
Switching-Type Self-Tuning Fuzzy PID Control of an Active Magnetic Bearing System
Authors: Chen Kuan Yu , Tung Pi Cheng , Fan Yi Hua
Published: March 2013

This paper presents a new switching control scheme for an active magnetic bearing (AMB) system using self-tuning fuzzy proportional-integral-derivative (PID) control. The research process consists of three stages. First, four types of self-tuning fuzzy PID-type controllers (FPIDCs) consisting of two most commonly used fuzzy inference systems: Mamdani and Takagi-Sugeno types, and two efficient parameter adaptive methods: function tuner and relative rate observer, are used to control a highly nonlinear AMB system, respectively. Hence, there are two kinds of FPIDCs can be obtained by comparing experimental results of these tests: one has the fastest transient response and the other has the minimum steady-state error. Next, the switching-type self-tuning FPIDC is proposed by combining the two kinds of FPIDCs. Namely, the AMB system is dominated by the scheme with the fastest transient response when the rotor is at rest and by the one with the best steady-state performance when the rotor is in rotation. Finally, experimental results demonstrate that the proposed switching-type self-tuning FPIDC performs better overall performance than the other self-tuning FPIDCs, particularly when controlling an AMB system.
The Study on Robust Controller Synthesis Using Genetic Optimization Algorithm Integrating Taguchi Methods
Authors: Shou Ho Nien
Published: March 2013

A controller synthesis algorithm is developed in this paper. The algorithm employs the genetic algorithm for parameter optimization and Taguchi method for the planning of trails in applying the genetic algorithms. The resulting two-phase algorithm explores the orthogonal array in Taguchi method to conduct a series of experiments so that key parameters pertaining to the control factors, noise factors, and quality factors can be determined. In the first phase, a matrix-type experiment is conducted to determine the configuration for parameter optimization. The second phase then applies parameter optimization method to determine the controller parameter that leads to robust performance. The combined two-phase approach is effective and efficient in controller synthesis. The proposed algorithm is applied to a control-design benchmark problem. The resulting design is shown to have a superior performance to other existing controllers.
Infrastructure Damage Reporting System with Location Awareness
Authors: Yen Tan Shiang , Osman Mohd Azam , Sing Ng Poh , Yong Tan Chee , Chan Steven
Published: March 2013

Complaints reported by the public about faulty or damaged infrastructure are important information for the management and maintenance team. Nonetheless, existing system to manage the complaint reports often has the problem of insufficient and ambiguous description about the reported infrastructure which resulting difficulties for the management to take action. The troublesome process of filing a complaint report could have reduced the willingness of public to make a report. Therefore, this paper is to introduce solution to the situation through an infrastructure damage complaining system with location awareness and photo capturing capabilities. The proposed system has been developed and thus the purpose of this paper is to introduce the system from the perspective of system design and architecture and to discuss the practical implications of the system. The proposed system provides an instant and convenient approach for the public to file a complaint report about damaged or faulty infrastructure. The public only need to take a photo with their mobile device and the system will automatically embed the coordination of the facility into the photo with geo-tagging technique. The simplified process of filing a complaint report may encourage the public to be more willing to collaborate with management. The visual information in the photo and location of the facility provide useful for the management team to accurately assess the severity of the damage thus to be able take informed action. As the outcome, the proposed system helps to achieve more effective and efficient management of public infrastructure.
Missile Guidance Algorithm Design Using Particle Swarm Optimization
Authors: Kung Chien Chun , Chen Kuei Yi
Published: March 2013

This paper presents a technique to design a PSO guidance algorithm for the nonlinear and dynamic pursuit-evasion optimization problem. In the PSO guidance algorithm, the particle positions of the swarm are initialized randomly within the guidance command solution space. With the particle positions to be guidance commands, we predict and record missiles’ behavior by solving point-mass equations of motion during a defined short-range period. Taking relative distance to be the objective function, the fitness function is then evaluated according to the objective function. As the PSO algorithm proceeds, these guidance commands will migrate to a local optimum until the global optimum is reached. This paper implements the PSO guidance algorithm in two pursuit-evasion scenarios and the simulation results show that the proposed design technique is able to generate a missile guidance law which has satisfied performance in execution time, terminal miss distance, time of interception and robust pursuit capability.
Using Bayesian Networks in Gear Fault Diagnosis
Authors: Wang Chun Chieh , Kang Yuan , Liao Chin Chi
Published: March 2013

In rotary machinery, the symptoms of vibration signals in the frequency domain have been used as inputs for neural networks and diagnosis results can be obtained by network computation. However, in gear or rolling bearing systems, it is difficult to extract symptoms from vibration signals in the frequency domain where shock vibration signals are present, and neural networks do not provide satisfactory diagnosis results without adequate training samples. Bayesian networks provide an effective approach for fault diagnosis in cases given uncertain knowledge and incomplete information. To classify the shock of vibration signals in the gear system, this study uses statistical factors of vibration signals. Based on these factors, the fault diagnosis is implemented by using Bayesian networks and the results of the two methods, namely, back-propagation neural networks and probabilistic neural network in gear train systems, are compared.
A Novel Data-Oriented Methodology for Designing Complex SOC System with Bluespec SystemVerilog
Authors: Chu Slo Li , Lo Min Jen
Published: March 2013

The continuously growing of semiconductor technology makes the novel SOC system complicated and hard to design. Conventional timing-control methodology focuses on the synchronizing the registers in a digital system. However, the central control of huge amount of synchronous signals and states is difficult to maintain and design, the debugging and verification period is extended accordingly. This paper proposed a novel deign methodology, called data-oriented methodology, to overcome the above challenges, by using Bluespec SystemVerilog and the corresponding tools. The simple handshaking mechanism and blocking mechanism are adopted to make sure the correctness of adjacent blocks, the complex centralized control unit can be reduced accordingly. Two examples, FDCT/IDCT and pipelined MIPS CPU, are provided to demonstrate two types of typical digital designs.
A Quick Response Power Factor Detector for Nonlinear Loads
Authors: Jiang Maoh Chin , Shih Bing Jyun
Published: March 2013

A fast power factor detector for nonlinear loads is proposed to overcome the drawback of conventional detectors, which can measure only the power factor of linear loads. The design of the proposed detector is based on the concept of additional characteristic of trigonometric function. It does not require any low-pass filter or integrator. Therefore, the transient response of the proposed detector is much faster than that of the conventional detectors. The theoretical response time of the proposed detector is less than one-fourth of a cycle. Because of its promising accuracy and rapid transient response, it can be used in many systems such as the control of power systems, and active power filters, to improve their transient performance. Theoretical analysis and experimental results are also detailed in this paper.
A Single-Phase Soft-Switching Unipolar PWM Rectifier
Authors: Jiang Maoh Chin , Fu Huang Kai , Lu Kao Yi
Published: March 2013

This paper proposed a novel single-phase soft-switching unipolar PWM rectifier (SSUPR) using a simple auxiliary resonant unit. All main switches of high-frequency arm operate at zero-voltage-switching (ZVS) turn-on, while the auxiliary switches operate at zero-current-switching (ZCS) turn-off. All main switches of low-frequency arm operate at 60 Hz to greatly reduce switching losses. Moreover, a soft-switching unipolar PWM strategy is used for the proposed soft-switching rectifier. This strategy results in a better input current waveform than for the bipolar PWM strategy. Furthermore, the proposed rectifier achieves a near unity power factor, a sinusoidal input current and a bidirectional power flow capability. Some experimental results of the proposed SSUPR, rated 500 W and operated at 40 kHz, are presented for verification.
Thermal Stabilities and Mechanical Properties of Two Tetra-Functional Epoxy Resins
Authors: Yu Ming Ming , Cui Yuan Yuan , Ma Xiao , Li Ai Jun , Bai Rui Cheng , Sun Jin Liang , Ren Mu Su , Hu He Feng
Published: March 2013

To study the relationship between the molecular main chain structure and the properties of amine based tetra-functional epoxy resins, especially for the thermal stabilities and the mechanical properties, N,N,N',N'-Tetraglycidyl-2,2-Bis[4-(4-aminophenoxy)phenyl]propane (TGBAPP) and N,N,N',N'-Tetraglycidyl-4,4'-diamino diphenyl ether (TGDDE) were cured with Methyl nadic anhydride (MNA). The thermal behavior of the cured epoxy resins were studied with the thermo-gravimetric analysis (TGA), and the glass transition temperature (Tg) were determined with the Dynamic Mechanical Analysis (DMA). Additionally, the mechanical properties of them were tested. The results indicated that the cured epoxy resin based on TGBAPP had better thermal stabilities and toughness.
Characteristics of Memristor Series-Parallel Connection Circuit with Applications
Authors: Yin Wei Hong , Wang Li Dan , Duan Shu Kai
Published: March 2013

Memristor is a nonlinear resistance with the ability of memory and its resistance depends on the amount of charge or magnetic flux. As a new circuit component, the memristor is not only expected to promote the evolution of electronic industry but also has huge potential application in many fields because of its small size, low energy consumption and be large scale integrated easily. In this paper according to the mathematical model of memristor based on a piecewise-linear function, the characteristics of memristor series-parallel connection circuit are analyzed by MATLAB and SPICE simulations. A series of simulation results show that the memristive series-parallel network is still a nonlinear element, the resistance value of memristor depends on the initial condition greatly and the electronic characteristics are more complex. It is also applied to the ladder signal generator which can be used in the controller circuit.
An Adaptive-Network-Based Fuzzy Inference System for Predicting Springback of U-Bending
Authors: Lin Bor Tsuen , Huang Kun Min , Kuo Chun Chih
Published: March 2013

Springback will occur when the external force is removed after bending process in sheet metal forming. This paper proposed an adaptive-network-based fuzzy inference system (ANFIS) model for prediction the springback angle of the SPCC material after U-bending. Three parameters were selected as the main factors of affecting the springback after bending, including the die clearance, the punch radius, and the die radius. The training data were obtained from results of U-bending experiment. The training data with four different membership functions – triangular, trapezoidal, bell, and Gaussian functions –were employed in the ANFIS to construct a predictive model for the springback of the U-bending. After the comparison of the predicted value with the checking data, we found that the triangular membership function has the best accuracy, which make it the best function to predict the springback angle of sheet metals after U-bending.
EMC Issues of Low Frequency Interference of Power Electronic Converters
Authors: Drabek Pavel , Kus Vaclav
Published: March 2013

Power electronic converters produce not only characteristic harmonics, but also both non-characteristic harmonics and interharmonics. This paper presents the physical background of both non-characteristic harmonics and interharmonics. Generation causes are explored and discussed in detail. Extensive series of simulation of different power converter topologies are provided and compared with experimental results and existing standards. This research offers missing background for standards covering low-frequency EMC.
Implemented LDO Chip With Output Capacitors Free
Authors: Tseng Hsien Wei , Lee Yang Han , Huang Chao Chung , Yen Liang Yu , Jan Yih Guang
Published: March 2013

In this paper the process of implementing a low dropout regulator (LDO) chip is presented; it is using uses Taiwan Semiconductor TSMC’s Manufacture Inc. 0.35um 2P4M process. The circuit designed with the described process can be is operated at 3-5V input voltage to generate 2.5V output voltage. Maximum output current can be running up to 200mA. This LDO is implemented without placing output capacitors to reduce BOM (Bill of Material) cost and stable between 0~200mA loading current and the chip is stable when the loading current is in the range 0~200mA. [8] The new proposed LDO chip can be implemented in the handheld mobile devices, battery powered equipment, wireless devices, cordless phones, or PC peripherals.
Towards Motion Recognition on Smartphone
Authors: Kwak Young Tae , Jo Hee Seung
Published: March 2013

With the advent of digital convergence trends, the current smartphone equipped with more powerful hardware and complex software to satisfy the increased user requirements. Additionally, similar to video game console, the pioneers of smartphone manufacturers consider adopting the motion recognition to extend their functionality. In this paper, we modify a commodity smartphone system to recognize the motion of users using an on-board camera and the OpenCV library. Additionally, we also implement a performance monitoring system which consists of a kernel monitoring module and a user-level logger. Based on the system, we analyze the performance impact and bottleneck of motion recognition with representative smartphone workloads, and propose the points for improvement in term of system architecture.
Analysis, Selection and Control of Optimal Driving Current Combinations in Wavelength Switching for DBR Lasers
Authors: Tseng Hsien Wei , Lee Yang Han , Lo Chih Yuan , Huang Chao Chung , Chuang Ming Hsueh , Jan Yih Guang
Published: March 2013

In this paper we exploit a basic type of three-stage Distributed Bragg Reflector (DBR) laser that by adjusting its input driving currents in the tri-electrode to generate signals with wavelengths that are in the International Telecommunication Union (ITU)-Band. Many driving current combinations can generate the same ITU wavelength; we will consider in this paper the situation when the input currents are restricted within certain range and to find for all those input current combinations that generate output signals with wavelengths locating in the ITU defined wavelength range. And we will through simulations to determine which set of current combinations will generate the shortest switching time. We will also propose a new current control method, when we know in advance the signal will be switched to certain band, to determine the best current switching combinations that resulting in faster and shorter switching time than that of the conventional system structure which has the drawback that it has only one fixed current combinations for each channel.
A Three-Dimensional Position System Using Digital TDE Receiver and Cylindrical Array Antenna
Authors: Mar Jeich , Wu Shin Ru , Wang Yu Ting , Tsai Kuei Chou
Published: March 2013

Based on the digital time delay estimation (TDE) and Gauss-Newton Interpolation algorithms, the circular error probability (CEP) of the proposed four-station position system using time difference of arrival (TDOA) over Rayleigh fading channel was studied by numerical computation in three-dimension space. The hybrid three-station TDOA and direction of arrival (DOA) position system was used to improve the reliability of four-station TDOA position system. Simulations indicate that the accuracy of the proposed position system is significantly decreased by reducing one measuring station and providing one direction of arrival (DOA) measurement.
Design of DDS-Like Clock Generator Using Bidirectional Integration
Authors: Chen Hsin Chuan
Published: March 2013

In many applications such as digital communication systems, a reconfigurable clock is required to switch the desired frequency at necessary time. However, using the conventional direct digital frequency synthesizer (DDS) as a pulse or clock generator may cause jitter problems, therefore phase-interpolation approaches are used to generate a pulse or clock with correct time intervals. Focusing on design methodology, a high-precision DDS-like clock generator without phase accumulator and phase interpolation is proposed in this paper, which only uses the bidirectional integration on a single capacitor to directly achieve the clock output with correct time intervals. It also can avoid the impact on frequency error caused by the capacitance error. Therefore, the proposed DDS-like clock generator using bidirectional integration can provides a low-jitter and high-precision clock output, and it also has less hardware complexity.
Ergodic Channel Capacity of MIMO Transmission in Spatial Correlated-Fading
Authors: Chen Joy Long Zong , Yeh Lu Tsou , Liou Chieh Wen
Published: March 2013

In this article the MGF (moment generating function) obtained to determine the ergodic (average) channel capacity, and which is by passing the difficulty in calculating the pdf (probability density function) of SNR (signal-to-noise ratio) traditionally. Some numerical results are offered for validating the accuracy the theoretical deriver formulas. Furthermore, many plots work out from combination with different number of transmitter and receiver for comparison. It is valuable to note that the more the antenna numbers the larger channel capacity is not acceptable when the correlation coefficient is taken into account the system evaluation of a MIMO system.
Partition-Based Hybrid MIMO Decoding Schemes with Combined Depth- and Breath-First Search
Authors: Park Jong In , Lee Young Po , Yoon Seok Ho
Published: March 2013

In this paper, we propose a novel maximum likelihood (ML) decoding scheme based on the combination of depth- and breadth-first search methods on a partitioned tree for multiple input multiple output systems. The proposed scheme first partitions the searching tree into several stages, each of which is then searched by a depth- or breadth-first search method, possibly exploiting the advantages of both the depth- and breadth-first search methods in an organized way. Numerical results indicate that, when the depth- and breadth-first search algorithms are adopted appropriately, the proposed scheme exhibits substantially lower computational complexity than conventional ML decoders while maintaining the ML bit error performance.
A Cluster-Based Countermeasure against MAC Layer Attacks in IEEE 802.11 MANETs
Authors: Shi Fei , Liu Wei Jie , Jin Dong Xu , Song Joo Seok
Published: March 2013

MANETs become a considerable interest nowadays. However, these types of networks are vulnerable to a large group of attacks, e.g., MAC layer attacks. Most of the previous researches related to security issues focus on detection of misbehaviors after it occurred. We propose a new way of thinking to evade occurrence of misbehaviors. A novel clustering algorithm is presented using analytic hierarchy process to elect clusterhead. Afterwards, the clusterhead is required to assign backoff values to originators in its transmission range, which are also the members in the corresponding cluster, rather than permitting the originators to choose backoff values. Meanwhile, the elected clusterhead also monitors whether originators obey the backoff values. With the proposed scheme, the misuse of the backoff in MAC layer in 802.11 DCF can be prevented.
A Study of Bipolar Walsh-Hadamard Coding Method in Optical CDMA Networks
Authors: Yen Chih Ta , Chen Wen Bin
Published: March 2013

This study analyzes and calculates unipolar and bipolar coded configurations of spectral-amplitude-coding optical division multiple access (SAC-OCDMA) systems by using analytic and simulated methods. The important feature of the SAC-OCDMA systems is that multiple access interference (MAI) can be eliminated by code sequences of a fixed in-phase cross-correlation value. This property can be effectively canceled by multiple access interference by using balance detection schemes. This study uses Walsh-Hadamard codes as signature codes for the unipolar and bipolar schemes. The coder and decoder structures are based on optical filters of fiber Bragg gratings (FBGs). The simulation results of unipolar/bipolar coding structures are first presented by commercial simulation obtained using OptiSystem software. The simulation results show that the bit error rate (BER) through use of the bipolar coding method is superior to the unipolar scheme, especially when the received effect power is large. The eye diagram also shows that the bipolar encoding structure exhibits a wider opening than the unipolar encoding structure.
Design of a LED Module with Special Constraint
Authors: Shaw Dein , Huang Yan Ching
Published: March 2013

LED gradually replaces light source in many fields, it becomes more and more important. For the purpose of letting LED more effective, people usually use secondary optical lens to improve the optical quality. In this research, reflector and lens are used to compose a LED light module. In this study, a LED module is designed to meet the specific requirement of the illumination. It was found that changing lens thickness and lens position can improve the uniformity and the size of light patch. As a result, we found parameters about lens for best results. In the design process, we realized that uniformity can be increased by decreasing D10 value of the light. The best result of simulation was found (which are in the form of point data). We used polynomials to fit the contour of LED module of point data and used it to extend the reflector contour of calculated results. The size of light patch of LED contour with reflector-masked and point data is much smaller than with polynomials.
Design of an Optical Mechanical System for High-Resolution Encoders
Authors: Fan Yi Hua , Chen Ching En , Lou Liao Yong , Chen Chun Yu
Published: March 2013

An optical mechanism composed of a movable part and a fixed part for the increment high-resolution optical displacement encoders is proposed in this paper. The parallel light emitted from the movable part passes through a double-concave lens and a specially designed optical grating; it is then projected onto a phototransistor array receiver to indicate the displacement of the movable part. The relationship equation of the lens is developed to design an optical mechanism which can enlarge the displacement so that it becomes observable. Based upon the simulation results, a specially designed optical grating is designed to compensate for the deviations on the detecting surface and to derive the increment movement of the light source. The simulation results indicated that the optical mechanism with 50 times magnification could make the 10 nm movement intervals of a light source be about 500 nm movement intervals in the detecting surface. Furthermore, an experimental system with a 200 nm resolution is established to verify the possibility of the proposed structure.
Development of a Light Guide Film with Optimal Design and Roll to Roll Microfabrication Technology
Authors: Wang Min Wen , Lin Wei Chuang , Lee Ming Hsiao
Published: March 2013

Neural network optimal optical design and Roll to Roll (R2R) microfabrication has been integrated in the development of a light guide film (LGF) for liquid crystal display application in this study. TracePro software was used for optical simulation work for the light guide film. Back-propagation neural network (BPNN) was applied to establish a light guide film optical quality predictor. Combined with genetic algorithms (GA), global optimization of the optical quality was achieved. The optimal pattern radii of different zones range from 40 μm to 210 μm were first transferred to an 80 μm thick stainless steel sheet through lithograpgy and etching process. The patterned sheet was then wrapped around the stainless steel roller for R2R fabrication of the patterns on a 188 μm thick PET substrate with UV resin. When operated with imprinting pressure of 0.61 MPa and substrate speed of 0.251 m/min, the LGF measurement results showed that the replication rate is around 98% while the luminace uniformity reaches 74.9%.
High Efficient Color-Separation Backlight
Authors: Lee Chi Hung , Huan Tsung Hsien
Published: March 2013

To replace the color filter in the conventional display, we describe a color-separation backlight consisting of three modules: the light collimation module, the light guide and the micro-lens array. With angularly positioned color LEDs, the displaying method requires only two two-color filter layers to display color images. In the light collimation module, the angular rays of two colors from each LED are collimated by a reflective cup and a collimation lens. After entering the light guide, which is composed of V-groove structures at the bottom above a reflective layer, the angular collimated color beams are redirected to the normal of the top surface of light guide. Finally, the output rays are converged by a micro-lens array and mapped into corresponding sub-pixel positions for efficiently displaying color image. The three main advantages of such technology are the reduction of the dye color filter layers from conventional 3 to 2, the gain factor of transmission efficiency two times more than that of conventional color filters, and the larger color gamut.
Interactive Design and Simulation for Luneberg Lenses
Authors: Ueng Shyh Kuang , Muh Hsuan
Published: March 2013

In this paper, a CAD system is presented for the design, evaluation and simulation of Luneburg lenses. Since this system focuses on high-frequency spherical antenna design and simulation, electromagnetic waves are replaced by rays. A ray-tracing subroutine is employed to trace ray paths and compute phase variations along rays. In traditional CAD systems, the performance of a Luneburg lens is measured by using numerical algorithms, which are difficult to implement and require tremendous computational efforts. In the proposed system, the effectiveness of the target lens is evaluated solely by using the theory of Geometrical Optics (GO). Ray paths and wavefronts are rendered and displayed to show the directivity and focus characters of the lens. The ray phases along with ray paths are also illustrated in graphical media so that the gain and reflectivity of the lens can be predicted.
The Convergence Rate on Distributed Network Utility Maximization in Wireless Mesh Networks
Authors: Chen Yi , Gao Ge , Liu Ming , Wang Sai
Published: March 2013

One of the major factors that affects the distributed network utility maximization(NUM) is the exchange message delay which leads to oscillations due to imperfect response to time-variant channel. In this paper, a novel technique is presented to solve the reverse impact control delay in distributed NUM of wireless mesh networks. Simulation results illustrate better performance.