Showing papers in "Journal of Qingdao University in 2013"

Fuzzy Formation Control of Multiple Robot Fishes Under Leader-Follower Framework

Abstract: In the formation control of multi-robot fish system,the robot fishes usually cannot react quickly to the sudden change of formation.To cope with this problem,fuzzy control is adopted in the paper to control the velocity and heading angle of robot fishes so that the followers can reach the desired position and orientation quickly and accurately.Meanwhile,three fishes are taken as an example in the simulation verification for formation movement of multiple robot fishes.When the leader moves straight,simulation results show that followers and the leader have the same velocity and movement.When the leader changes direction and velocity,followers can reach the expected position in a short time by adjusting the speed gears and direction of stalls,and at the same time keep apredetermined formation.The approach can adjust the motion parameters,maintain the formation configuration,prompt multiple robot fishes to complete the predetermined route with a desirable formation,and achieve a good effect of following.

Double Wishbone Suspension Stress and Finite-Element Analysis for FSC Racing

Abstract: The traditional calculation method to solve the problem of FSC racing double wishbone suspension rod force is complicated.This paper uses Matlab software to study the suspension of the rod force,sets up mechanical model of suspension,and carries out stress analysis on the model by using analytical method.Meanwhile in the Solidworks software,it establishes the rod model and import Workbench software to do finite element analysis of strength.Analysis results show that the maximum rod stress is 36.478MPa,far less than the tensile strength of carbon fiber tube material.The design can quickly and accurately calculate the suspension of each member 's force,can solve the complex problem of traditional calculation,get well prepared for finite element analysis of double wishbone suspension rod analysis,and it has good application value.

A Method of Metro Vehicle Auxiliary Inverter Fault Diagnosis Based on Fuzzy Clustering Arithmetic

Abstract: In this paper,the authors study the application of the fuzzy C-means clustering algorithm in the fault diagnosis of auxiliary inverter based on the basic principle of wavelet packet frequency band energy decomposition and the fuzzy C-means clustering algorithm in order to solve the problems of auxiliary inverter causing by its complicated structure.Using MATLAB software as the platform to simulate the fault signal,several fault types are set during the simulation,such as variations of voltage frequency,interruption of power supply,pulse transient and so on.Based on the decomposition of wavelet packet frequency band energy,the fault feature vectors can be extracted as the standard samples of fault diagnosis,then calculating the similarity degree of the samples to be diagnosed and the standard samples to realize the recognition of fault pattern.The simulation results show that the faults can be identified accurately based on FCM algorithm.This research provides theoretical basis for auxiliary inverter system fault diagnosis of metro vehicle.

Modeling and Simulation of IM Four-Quadrant Control Systems Based on Back to Back Converter

Abstract: For squirrel cage induction motor drive system of the four-quadrant control problem,the mathematical models of the net side converter and machine side converter are established.The control methods of the net side converter and machine side converter are given and the controllers of the net side and machine side are calculated.The voltage outer ring and current inner ring double closed loop are used in the net side.The speed outer ring and current inner ring double closed loop are used in the machine side.The coordinated control strategy of the net side and machine side is used,which machine side is started after the net side is close to being stable.The control system can be achieved that the DC bus voltage is controllable,power factor of the net side is 1,energy is bidirectional flow,IM can run in the four quadrant and the tracking of motor speed is rapid and accurate,etc.

Research on Application of Principal Component Analysis in Computer Color Matching for Textile Dyeing

Abstract: Aiming at solving the complex nonlinear problem of fabric dyeing color matching,we mainly get the basic relationship between textile dye recipe d 1,d 2,d 3 and their three stimulus valuesIn order to get more data,one-dimensional and two-dimensional interpolations to the experimental data are done respectivelyNext the nonlinear equation of textile dye recipe and three stimulus values C,M and Yis established by using Matlab fitting toolbox and multivariate nonlinear regressionFinally,the nonlinear equation is solved by Newton iterative method to get the textile dye recipeThe experiment results show that the textile dye recipe we get by the model is very close to the actual measured values and the absolute value of error is less than 005The model has a high precision and a good accuracy and it can be applied to the actual color matching

Research of Partial Commitment Repurchase Mode for Confirmed Warehouse Based on VaR

Abstract: In the traditional confirmed warehouse business,there is a problem that providers are reluctant to commit to repurchase totally.This paper introduces the concept of VaR into confirmed warehouse business and measures the risk of the business for the bank.The supplier commits partial repurchase,and then the repurchase amount range of supplier and the margin ratio of distributor are analyzed and determined,As a result,the bank and the supplier share risks and ensure the implementation of the business.

Analysis of Affecting Factors for Commercial Banks' Service Quality Based on QFD

Abstract: According to the improved SERVQUAL model,the questionnaire is designed to obtain the customer's demands.Basis on the of method QFD,the relative matrix that connects the customers' demands with the banks' interval technical measures was built,and the key factors which affect the commercial banks' service quality such as the bank's technic,staff management and service concepts were obtained.

3D Reconstruction from a Single Image Based on the Geometric Properties of the Object

Abstract: 3D reconstruction from a single image has been an active research topic for many years,which needs less information and avoids the matching difficulty of the 3D reconstruction of multiple images.The calculation of objects' depth value is a hard work for reconstruction from a single image.In order to figure out this problem,some objects are rebuilt by using the geometric properties of rule geometry from a single image.Firstly,the camera is calibrated by using the vanishing points.Secondly,the least two-dimensional points needed are captured manually,and the geometric properties of the objects are calculated by using calibration matrix and geometric constraints.Finally,the 3D reconstruction and texture mapping is implemented by OpenGL.The experiments demonstrate that this approach can recover the entire three-dimensional structure of the object accurately and meet the needs of the general virtual reality.

Fabrication of Fluorescent Nanofibers of Aligned Arrays, Two-Layer Grid-Patterns and Nanoropes via Electrospinning

Abstract: Fluorescein/PMMA and rhodamine B/PS composite nanofibers acting as aligned arrays,two-layer grid-patterns and nanoropes were preparaed via electrospinning,respectivelyThe morphology and the fluorescence were observed by SEM,fluorescence microscope,and fluorescence spectrum techniquesResults show that the fluorescence intensity of the nanoropes is much higher than that of assemble of individual nanofibers

Study of the Garment Enterprises Diversification Development Trend Based on the Long Tail

Abstract: Aimed at the problem that the intensive competition and depressed profit result from the clothing homogeneity of the garment enterprise,based on the long tail theory,the long tail model was introduced and five long tail mode curves were analyzed,the effect factors of dress breed diversification and the garment enterprises diversification development trend were investigated.The study showed that the basic factor influenced the modification of the whole long tail model is dress breed diversification,and with the different stage of social development,the influencing factor of dress breed diversification has different influence level,influencing factor in each stage has more than one factor,and is different from the accordance with the long tail curve law.The study can provide a basis for the development of long tail market of clothing enterprises and the establishment of related policies,and lay a theoretical foundation for the diversification development of the garment enterprises.

Prediction of Stock Return Rate and Relationship Between Risk and Return——Based on ARMA-GARCH Model and High-frequency Data

Abstract: By using the high-frequency data of the CSI 300 index,ARMA model and GARCH(1,1)-T model are applied to fit and forecast the rate of return.In addition,GARCH-M model is selected to measure the relationship between risk and return.Experimental results show that the change of return rate has the feature with conditional heteroskedasticity;ARMA model is suitable for the long term prediction and GARCH(1,1)-T model is suitable for the short term prediction;As risk and return don't present positive relationship,our stock market isn't ripe.

Image Feature Extraction of Fabric Defect Based on Wavelet Transform

Abstract: In order to realize automatic fabric defect detection,Mallat algorithm has been used to implement wavelet decomposition of a fabric image.According to fabric texture's structure characteristics,five eigenvalues,namely the energy,entropy,extreme difference,variance and inverse difference,were extracted from weft sub-image and warp sub-image respectively.In this paper,the tabby cloth was chosen as experimental object,and the eigenvalue extraction experiments were carried on various common defects,such as white streak,weft-lacking,broken hole,anti-silk,miscellaneous fiber,buckle-off,loom fly,unclean color and so on,and the eigenvalue changes caused by different " strip-shape " defects and " area-shape " defects were analyzed,and the correlativity between eigenvalue changes and defect trend.The results showed that the method has the inference value to determine the existence of defects,defect analysis of the direction and " shape " has the reference value.

State Feedback Admissible Control for Linear Singular Delta Operator Systems

Abstract: This paper mainly deals with the problem of state feedback admissible control for linear singular delta operator systems via linear matrix inequality(LMI) method.A new necessary and sufficient condition is derived for the admissibility of linear singular delta operator systems and a suitable state feedback controller is designed for linear singular delta operator systems which are not admissible,such that the resulting closed-loop systems are admissible.A numerical example demonstrates that all the results in this paper are effective and tractable.

Design of CAN Bus Analyzer Based on STM32F103 MCU

Abstract: For CAN bus networks with different protocols and baud rates,this paper takes STM32F103as the primary controller and designs a type of analyzer to monitor different states of CAN bus.STM32F103can communicate with CAN bus through extemal CAN receiver TJA1050,realizing the data collection and processing of CAN bus.The test results show that,the monitoring to the bus throughput is 10fps / s when the baud rate is 5kbps / s and the sending packets interval is 100ms.The measured bus loads and bus throughput are matched the actual.This type of analyzer provides rapid and exact solutions to the fielding monitoring and troubleshooting of CAN bus and can realize the reliable real-time monitoring of CAN network.