Numerical Analysis and Scientific Computing Commons^™

Modeling And Numerical Simulation Of Tissue Engineering Scaffold 3d Printing Process, Congping Chen, Jieguang Huang, Hu Qiong, Yanhua Ran, Li Bo

Journal of System Simulation

Abstract: In the process of tissue engineering scaffold fabrication using injecting 3D printing, the viscous fluid material is extruded out with a style of microfilament, which is deposited on a substrate layer by layer. The materials spread, pile up, remelt and solidify as a consequence of the couple effects of gravity, surface tension, viscous force and solidification drag force. Aiming at the above issues, the forming process of scaffold with homogeneously-sized space pores is studied with a CFD approach to research the pore forming mechanism. The results show that the viscous fluid is cooled mainly by the substrate, and heat …

Parameter Identification For Pmsm Based On Multi-Innovation Approximate Least Absolute Deviation Identification Algorithm, Dinghui Wu, Jianyu Zhang, Yanxia Shen, Zhicheng Ji

Journal of System Simulation

Abstract: In view of the problem that the results of traditional identification algorithm are not accurate caused by the peak noise signal in the environment, a new algorithm based on the forgetting factor multi-innovation approximate least absolute deviation (MIALAD) identification algorithm is proposed. Combined with the system voltage equation of permanent magnet synchronous motor (PMSM), a discrete identification model is constructed. By using vector control method, the input and output data of the identification model are obtained to identify the rotor resistance and inductance. The simulation results show that this identification algorithm can obtain the accurate parameters of the PMSM …

Discrete Control Simulation Of Agitation Tank Based On Taylor Finite Difference, Yunong Zhang, Yaqiong Ding, Le Li, Deyang Zhang, Binbin Qiu

Journal of System Simulation

Abstract: Zhang dynamics is used to solve the system equations of the agitation tank to get controllers. At the same time, Taylor finite difference method is used in the computer discrete control simulation for the agitator tank system. In addition, the convergence stability of Zhang dynamics applied to the agitation tank is proved through theoretical analysis. In order to achieve the draining purpose for the agitation tank, the computer discrete control simulation is conducted by means of MATLAB. For comparison, the computer simulation based on the neural network predictive controller is carried out. The comparative simulation results substantiate the …

Fast False Scene Jamming Algorithm For Sar-Gmti Based On Moving Jamming Station, Mingxing Fang, Daping Bi, Aiguo Shen

Journal of System Simulation

Abstract: Traditional false scene jamming of SAR is invalid for SAR-GMTI system, which does not have the feature of moving targets, so a fast false scene jamming algorithm for SAR-GMTI based on moving jamming station is proposed. Through reasonable simplification of the traditional algorithm, the fast false scene jamming algorithm of matrix form is put forward. The method is proposed to take advantage of both fast false scene jamming algorithm and moving jamming station, so it can produce false scene jamming with real moving feature. It not only solves the real-time problem of traditional false scene jmming, but …

Smooth Transition Method Over Entire Speed Range Of Switched Reluctance Motor, Diansheng Sun

Journal of System Simulation

Abstract: In order to smoothly switch different control modes of switched reluctance motor under the condition of low speed and high speed, a novel scheme using function fitting method to control turn-on angle, turn-off angle and phase current chopping is proposed. The active disturbance rejection speed control system is structured for switched reluctance motor in order to restrain all kinds of disturbance and improve the dynamic performance. Simulation results indicate that the principle of the method is correct and the turn-on angle, turn-off angle and phase current chopping is coordinated to realize the smooth switching of different control modes with …

A Novel Algorithm For Improving Fairness Between Uplink And Downlink Flows In Heterogeneous Network, Peiyu Li, Zheqing Li, Wang Hui, Xia Qian

Journal of System Simulation

Abstract: In order to improve the fairness between uplink and downlink flows in AP optimization, a novel algorithm called FOUD(fairness over uplink and downlink) is proposed.Considering the influence of the attempt limit and the bit error rate of wireless, the FOUD algorithm modeling of AP and wireless stations is studied separately by using two-dimensional Markov chain, which derives the probability of data sending under the condition of different bit error rate and different number of uplink and downlink flows. Simulation results show that FOUD can improve the fairness of the uplink and downlink bandwidth as well as the …

Frequency Domain Analysis Of Common Configuration Semi-Submersible Drilling Platform Based On System Simulation, Chen Bo, Zhiyong Yu, Lü Yong, Xiaojian Li

Journal of System Simulation

Abstract: To analysis of 4 semi-submersible drilling platform hydrodynamic performance providing a comprehensive guidance for system selection. The 1:1 3D wet surface model is established by ANSYS and numerical simulation is carried out based on the dynamic analysis software AQWA. Simulation results show that longitudinal waves impact the surge, heaving and pitching motion a lot, beam seas have large effects on the sway, heave, roll motion vertical heave response increases significantly, as will as surge, sway, heave damping coefficient of vector direction and the added mass coefficient of algebraic. We can not only increase the number of columns to …

Structure Optimization Analysis Of Multi-Span Antisymmetric Arch Tower Cable-Stayed Bridge, Xijun Liu, Yuan Bo, Tianyi Liu

Journal of System Simulation

Abstract: In order to analyze its force under different sections and arch span ratio of the Antisymmetric arch tower cable-stayed bridge, the paper takes an anti-symmetric arch tower cable-stayed bridge as an engineering example. Considering the effect of dead load and temperature, finite software is used to calculate the stress of the arch tower and deflection of the deck and its corresponding dynamic characteristics under different types of arch sections and different rise-span ratio of the arch. The results show that the circular cross-section has better mechanical performance compared with other types of arches tower section with the same …

Fuzzy Sliding Backstepping Mode Control For Flight Simulator Servo Based On Friction And Disturbance Compensation, Huibo Liu, Shanglei Liu

Journal of System Simulation

Abstract: Considering friction, modeling errors and other uncertainties of flight simulator servo system, a compensation strategy which combines model-based friction compensation with nonlinear disturbance observer compensation was proposed. First, the friction is modeled , whose parameters are identified by using genetic algorithm, and using the identified model to compensate. Second, using a nonlinear disturbance observer to estimate the modeling errors, friction less-compensation or over-compensation and other uncertainties, and using this observed value to compensate. The system adopted sliding backstepping controller to ensure the stabilization of the system. Finally, the fuzzy algorithm is adopted to adjust the switching gain of sliding …

Interval Fuzzy Modeling Based On Minimizing-Norm On Approximation Error, Xiaoyong Liu, Zhonggang Xiong, Changguo Yan

Journal of System Simulation

Abstract: As the obtained data in many practical applications tend to be uncertain or inaccurate, conventional modeling methods characterized by deterministic model for this type of data have become undesirable. Taking linear programming and TS fuzzy model and some ideas from norm minimization into consideration, a novel method identifying interval fuzzy model (INFUMO) consisting of upper and lower TS fuzzy model (referred to as f_U and f_L) has been studied. In order to solve INFUMO, optimization problems based on minimizing-norm with respect to approximation error corresponding to f_U and f_L are constructed. Finally, optimization problems …

Preliminary Study Of Modeling And Simulation Technology Oriented To Neo-Type Artificial Intelligent Systems, Libo Hu, Xudong Chai, Zhang Lin, Li Tan, Duzheng Qing, Tingyu Lin, Liu Yang

Journal of System Simulation

Abstract: A brief interpretation of the rapidly developing “New Internet+ Big Data+ Artificial Intelligence+” era is given in the paperand the essence and the architectureof neo-type artificial intelligence systems are explained. The meaning of neo-type artificial intelligence system oriented modelling and simulation technology is proposed and the new challenges they are facing are discussed. The research contents and preliminaryresults on neo-type artificial intelligence system oriented modelling and simulation technology are given, which includeneo-type artificial intelligence system oriented modelling/secondary modelling, intelligent simulation computer, smart cloud simulation and intelligent simulation hardware/software supporting system technology, and intelligent simulation system application engineering technology. Several …

Prediction Model Of Particle Size Distribution In Bauxite Continuous Ball Milling Process, Tianyu Ma, Yalin Wang, Kun Shen, Jinping Liu

Journal of System Simulation

Abstract: As it is difficult to detect the particle size distribution of ball milling process on line, a prediction model of particle size distribution in bauxite continuous ball-milling process is proposed, which is based on data-driven method and population balance model (PBM) frame. The break-rate model structure of PBM is improved according to the characteristic data of batch grinding test of bauxite. The residual time distribution density function is improved by considering the characteristics of residence time distribution for different particle sizes. The key parameters of the model are optimized by the data of batch-test and continuous ball-milling process using …

A Method Of 3d Scattering Center Extraction Based On Multiple Hrrp Series, Cui Shan, Li Sheng, Yan Hua

Journal of System Simulation

Abstract: Scattering center extraction is the key content in the research of radar target characteristics, particularly the sliding type of scattering center. An extraction method based on the parametric scattering center model is proposed, which takes advantage of Hough transformation to extract geometric location and sliding radius parameters. The distance is gotten in the line of radar sight, and the useful information is obtained from high-resolution range profile (HRRP) series, which estimates size parameter of scattering centers and accomplishes signal reconstruction. This method solves the problems of point and sliding scattering center extraction. Simulation example manifests the applicability of the …

Modeling And Simulation Of The Crosstalk On Aircraft Arinc429 Data Bus, Xudong Shi, Ruowen Wang, Jialin Wang, Hongxu Zhao

Journal of System Simulation

Abstract: Based on the theory of multi-conductor transmission line, the crosstalk between a single cable and a UTP (unshielded twisted pairs) cable was studied. The MATLAB and CST were employed to do the theoretical calculation and modeling respectively, and the comparison result proved the validity and accuracy of the proposed model. Based on the UTP model, the shielding layer was used to build the STP（shielded twisted-wire pairs） model according to the ARINC429 specification, and the crosstalk which caused by a large voltage transient happening on the adjacent power line on the aircraft was further analyzed. The distance and length of …

Simulation Of Stone Cutting Process Based On Adaptive Coupling Method, Yongjun Tian, Guolin Duan, Junguang Kang, Jianhua Gang

Journal of System Simulation

Abstract: Aiming at complex nonlinear dynamic behaviors of stone-cutting process with circular saw and handling large mesh deformation instability in FEM, according to brittle material fracture mechanism, an adaptive coupling algorithm was established for calculating the cutting process of circular saw-stone materials system. The results show that the material removal process is a process of intermittent cycle; the cutting force is zero at the beginning of the process, and the force increases rapidly when the blade contacts with the stone, then decreases, eventually varies in a stable fluctuation. According to von-Mises stress distributions of saw blade and stone, the easily …

Fault Diagnosis System Of Lithium Battery Based On Petri Net, Diju Gao, Lan Xi, Aidi Shen

Journal of System Simulation

Abstract: To improve the efficiency of lithium battery fault diagnosis system, a fault diagnosis system based on Petri net is proposed. The fault diagnosis model based on Petri net came from the analysis of the inconsistent voltages between single cell in lithium batteries during charge and discharge. The system can find the fault causes according to abnormal signals detected by sensor. The control logic diagram of the fault diagnosis model is established by state flow, and simulated by simulink. The results of model verification and simulation show that the cause for inconsistent voltage is distinguished meticulously by the fault diagnosis …

Research And Simulation For Military Contests Based On Ahp And Entropy Models, Rusheng Ju, Zhengqiu Zhu, Yunxiu Zeng, Ruixian Wang, Xiaogang Qiu

Journal of System Simulation

Abstract: The paper studiesthe comprehensive military contests which are held frequently among military universities. Different from the qualitative analysis methods before, an analytic hierarchy process model is set up to analyze the effects which training programs have on students. A great amount of data is put into the entropy model to analyze the rationality of AHP model. This paper also sets the effect value as the input data of the emulating model to simulate the whole exercise process before contests which can verify the results received from AHP and entropy models. Research findings are helpful for superior leaders to make …

Disturbance Rejection Based Robust Control Approach For Servo System With Backlash, Chongwei Han, Peng Chao, Zhixiang Shi, Li Zhong

Journal of System Simulation

Abstract: With the rapid development of industry and science technology, the control performance requirements for servo system become higher and higher. Aiming at the servo system with backlash, a disturbance rejection based robust control approach is studied, which sees the backlash as external disturbance. It utilizes a disturbance rejection compensator to reduce the adverse effects caused by backlash, a mixed sensitivity based robust feedback controller to enhance the tracking control precision and robustness. The model of the servo system with backlash is built based on the analysis of system structure and work principle. The control principle, the robust disturbance rejection …

Research On Wind Turbine Test System Based On Jointsimulation, Zhongyue Song, Zhen Dong, Zhang Hao, Zhanqun Shi, Jiaojiao Ma

Journal of System Simulation

Abstract: As the test equipment of wind turbine can not simulate wind driven exactly and the impact of environmental factors is hard to be taken into account, the simulation results have larger errors. The problem is solved by establishing the virtual test bench in the way of combined simulation. The wind speed modelis optimized by combining the fitting of probability and the combinated wind speed model to drive the wind turbine;and the settings of some relevant contact force parameters are considered,which canmake the simulation results are closer to the actual situation. The credibilityof the system isdemonstrated and the validity …

Uav Attitude Control With Lqr Controller Based On Extended State Observer, Pan Jian, Changlong Liu

Journal of System Simulation

Abstract: Due to the external disturbances and parameter variations in the complex environment, the traditional linear quadratic controller (LQR) may induce instability to the controlled object. A control strategy of LQR based on extended state observer (ESO) is proposed, which aims to ensure the working reliability of the controlled object in complex environment. The nonlinear mathematical model of the quadrotor Qball-X4 is established. The ESO’s abilities of estimating and compensating the impact of internal/external disturbances simultaneously are used to improve the LQR attitude controller. Matlab/Simulink simulation and an experiment of trajectory tracking on the quadrotor Qball-X4 verify the validity …

Analysis Of Bus Ride Comfort Using Smartphone Sensor Data, Hoong-Chor Chin, Xingting Pang, Zhaoxia Wang

Research Collection School Of Computing and Information Systems

Passenger comfort is an important indicator that is often used to measure the quality of public transport services. It may also be a crucial factor in the passenger’s choice of transport mode. The typical method of assessing passenger comfort is through a passenger interview survey which can be tedious. This study aims to investigate the relationship between bus ride comfort based on ride smoothness and the vehicle’s motion detected by the smartphone sensors. An experiment was carried out on a bus fixed route within the University campus where comfort levels were rated on a 3-point scale and recorded at 5-second …

Feasible Form Parameter Design Of Complex Ship Hull Form Geometry, Thomas L. Mcculloch

LSU New Orleans Theses and Dissertations

This thesis introduces a new methodology for robust form parameter design of complex hull form geometry via constraint programming, automatic differentiation, interval arithmetic, and truncated hierarchical B- splines. To date, there has been no clearly stated methodology for assuring consistency of general (equality and inequality) constraints across an entire geometric form parameter ship hull design space. In contrast, the method to be given here can be used to produce guaranteed narrowing of the design space, such that infeasible portions are eliminated. Furthermore, we can guarantee that any set of form parameters generated by our method will be self consistent. It …

Empathetic Computing For Inclusive Application Design, Kenny Choo Tsu Wei

Dissertations and Theses Collection (Open Access)

The explosive growth of the ecosystem of personal and ambient computing de- vices coupled with the proliferation of high-speed connectivity has enabled ex- tremely powerful and varied mobile computing applications that are used every- where. While such applications have tremendous potential to improve the lives of impaired users, most mobile applications have impoverished designs to be inclusive– lacking support for users with specific disabilities. Mobile app designers today haveinadequate support to design existing classes of apps to support users with specific disabilities, and more so, lack the support to design apps that specifically target these users. One way to resolve …

Fogfly: A Traffic Light Optimization Solution Based On Fog Computing, Quang Tran Minh, Chanh Minh Tran, Tuan An Le, Binh Thai Nguyen, Triet Minh Tran, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

This paper provides a fog-based approach to solving the traffic light optimization problem which utilizes the Adaptive Traffic Signal Control (ATSC) model. ATSC systems demand the ability to strictly reflect real-time traffic state. The proposed fog computing framework, namely FogFly, aligns with this requirement by its natures in location-awareness, low latency and affordability to the changes in traffic conditions. As traffic data is updated timely and processed at fog nodes deployed close to data sources (i.e., vehicles at intersections) traffic light cycles can be optimized efficiently while virtualized resources available at network edges are efficiently utilized. Evaluation results show that …

Automatic Identification Of Animals In The Wild: A Comparative Study Between C-Capsule Networks And Deep Convolutional Neural Networks., Joel Kamdem Teto, Ying Xie

Master of Science in Computer Science Theses

The evolution of machine learning and computer vision in technology has driven a lot of

improvements and innovation into several domains. We see it being applied for credit decisions, insurance quotes, malware detection, fraud detection, email composition, and any other area having enough information to allow the machine to learn patterns. Over the years the number of sensors, cameras, and cognitive pieces of equipment placed in the wilderness has been growing exponentially. However, the resources (human) to leverage these data into something meaningful are not improving at the same rate. For instance, a team of scientist volunteers took 8.4 years, …

A Multi-Task Approach To Incremental Dialogue State Tracking, Anh Duong Trinh, Robert J. Ross, John D. Kelleher

Conference papers

Incrementality is a fundamental feature of language in real world use. To this point, however, the vast majority of work in automated dialogue processing has focused on language as turn based. In this paper we explore the challenge of incremental dialogue state tracking through the development and analysis of a multi-task approach to incremental dialogue state tracking. We present the design of our incremental dialogue state tracker in detail and provide evaluation against the well known Dialogue State Tracking Challenge 2 (DSTC2) dataset. In addition to a standard evaluation of the tracker, we also provide an analysis of the Incrementality …

Analyzing And Modeling Users In Multiple Online Social Platforms, Roy Lee Ka Wei

Dissertations and Theses Collection (Open Access)

This dissertation addresses the empirical analysis on user-generated data from multiple online social platforms (OSPs) and modeling of latent user factors in multiple OSPs setting.

In the first part of this dissertation, we conducted cross-platform empirical studies to better understand user's social and work activities in multiple OSPs. In particular, we proposed new methodologies to analyze users' friendship maintenance and collaborative activities in multiple OSPs. We also apply the proposed methodologies on real-world OSP datasets, and the findings from our empirical studies have provided us with a better understanding on users' social and work activities which are previously not uncovered …

Enhancing 3d Visual Odometry With Single-Camera Stereo Omnidirectional Systems, Carlos A. Jaramillo

Dissertations, Theses, and Capstone Projects

We explore low-cost solutions for efficiently improving the 3D pose estimation problem of a single camera moving in an unfamiliar environment. The visual odometry (VO) task -- as it is called when using computer vision to estimate egomotion -- is of particular interest to mobile robots as well as humans with visual impairments. The payload capacity of small robots like micro-aerial vehicles (drones) requires the use of portable perception equipment, which is constrained by size, weight, energy consumption, and processing power. Using a single camera as the passive sensor for the VO task satisfies these requirements, and it motivates the …

Tool For Correlating Ebsd And Afm Data Arrays, Andrew Krawec, Matthew Michie, John Blendell

The Summer Undergraduate Research Fellowship (SURF) Symposium

Ceramic and semiconductor research is limited in its ability to create holistic representations of data in concise, easily-accessible file formats or visual data representations. These materials are used in everyday electronics, and optimizing their electrical and physical properties is important for developing more advanced computational technologies. There is a desire to understand how changing the composition of the ceramic alters the shape and structure of the grown crystals. However, few accessible tools exist to generate a dataset with the proper organization to understand correlations between grain orientation and crystallographic orientation. This paper outlines an approach to analyzing the crystal structure …

Investigating Dataset Distinctiveness, Andrew Ulmer, Kent W. Gauen, Yung-Hsiang Lu, Zohar R. Kapach, Daniel P. Merrick

The Summer Undergraduate Research Fellowship (SURF) Symposium

Just as a human might struggle to interpret another human’s handwriting, a computer vision program might fail when asked to perform one task in two different domains. To be more specific, visualize a self-driving car as a human driver who had only ever driven on clear, sunny days, during daylight hours. This driver – the self-driving car – would inevitably face a significant challenge when asked to drive when it is violently raining or foggy during the night, putting the safety of its passengers in danger. An extensive understanding of the data we use to teach computer vision models – …