Computer Sciences Commons^™

Longitudinal Adaptive Control Of Autonomous Vehicles Base On Optimization Algorithm, Zhishuai Yin, Jiaxiong He, Linzhen Nie, Jiayi Guan

Journal of System Simulation

Abstract: Aiming at the nonlinear, time-varying and uncertain characteristics of the longitudinal motion of autonomous vehicles, a Radial Basis Function neural network(RBFNN) Proportional Integral Derivative(PID) controller base on Particle Swarm Optimization(PSO) is designed. A RBFNN is integrated into a PID controller so that parameters of the PID controller could be adjusted self-adaptively. To solve the problem that poor selection of initial parameters of RBFNN and PID might lead to overshoot or instability in the control system, PSO is adopted to optimize aforementioned initial parameters off-line. Finally, a closed-loop adaptive control system model is built in MATLAB/Simulink. Simulation results show that …

A Quantized State System Method With Adaptive Quantum, Zhihua Li, Dongjin Fu, Li Guang, Zhihua Fan

Journal of System Simulation

Abstract: Quantized state system (QSS) is a new numerical integration method. It has advantages over the traditional time-discrete integration methods in solving general ordinary differential equation (ODE) systems. But it is hard to choose an appropriate quantum for the QSS method. In order to improve the accuracy and efficiency of QSS, a quantized state system method with adaptive quantum (VQSS) is proposed. Combined with the idea of step control in the variable step Runge-Kutta method, it can adaptively change the quantum in the process of computation. The feasibility of this algorithm is verified by the simulation of two examples …

Visualization Of Tropical Cyclone Disaster Information Based On Cesium, Shuoben Bi, Yezhou Chen, Yucheng Gong, Mingyue Lu, Ruizhuang Xu

Journal of System Simulation

Abstract: The disaster information of tropical cyclones not only expresses the intensity, but also reflects the degree of influence on human life, which has very important research significance. At present, no scholar has given a dynamic visualization method based on Cesium for water flooding disasters, nor has it integrated with other disaster information of tropical cyclones. In response to these problems, a dynamic visualization method for water inundation is proposed, and it is integrated with other disaster information such as the path of tropical cyclone and loss caused by it in the same digital earth platform. Experiments show that the …

Spatio-Temporal Memory Models In Spatial Cognitive Behavioral Modeling, Hu Yue, Xu Kai, Qin Long, Quanjun Yin, Yabing Zha

Journal of System Simulation

Abstract: It is crucial for military simulation systems to model the layouts of spatial environments and the temporal logic of entity activities. To improve the human-likeness of Computer Generated Forces (CGFs) and the runtime efficiency of the systems, building spatio-temporal memory representations and reasoning mechanisms that accord to mankind cognition is required. The neuro cognition science background of spatio-temporal memory is presented, and the related work on modeling the memory in deep learning and computational intelligence communities is summarized. Following the OODA (Observe-Orient-Decide-Act) loop, a general framework of spatial cognitive behavioral modeling is designed and the application of spatio-temporal memory …

Research On Cgf-Oriented Virtual Human Perceptual Attention Model, Weilong Yang, Xu Kai, Xie Xu, Sun Lin

Journal of System Simulation

Abstract: Perception model is an important research field of CGF behavior modeling. As the input of the reasoning module, the information obtained from the perception model has an important influence on the fidelity of the simulation. The CGF perception model is researched, and the attention mechanism, effective time of attention model is analyzed, compared with the traditional model of perception. By modeling the knowledge base and information feedback, a virtual human perception framework based on attention mechanism is proposed, and the experiment is carried out in the simulation environment.

Review On The Construction And Application Of Digital Twins In Transportation Scenes, Zhaohui Wu, Zhenzheng Liu, Shi Ke, Wang Liang, Xiaojie Liang

Journal of System Simulation

Abstract: Digital twins connect the physical world and the information world, and provide new ideas for the analysis and solution of complex traffic problems. The research and application status of digital twins in transportation scenes are reviewed on the basis of sorting out the basic concepts, development history and key technologies of digital twins. The key technologies for the construction of digital twins in transportation scenes that need to be breakthrough are analyzed from the four aspects of "people-vehicle-road-environment" combined with the characteristics of the elements of traffic operation. The prospect of digital twin transportation applications in the development of …

Modulation Recognition Algorithm Based On Improved Lda And Autoencoders, Yecai Guo, Haoran Zhang

Journal of System Simulation

Abstract: The traditional modulation recognition algorithms are based on the Gaussian white noise channel, which significantly degrade recognition performance in complex channel conditions. Aiming at this problem, a modulation recognition algorithm based on A-ALDA (Anti-alias Linear Discriminant Analysis) and SSDAE (Stacked Sparse Denoising Autoencoders) is proposed. In this algorithm, A-ALDA algorithm reconstructs signal cumulants feature into new features, which has better separability. The combination of original features and new features is input into SSDAE for classification, and SSADE has the ability to extract key information and resist noise. Simulation results show that …

Preliminary Research On Verification And Validation For Cgf Behavioral Modeling, Jianbing Tang, Zhang Qi, Jiao Peng, Yabing Zha

Journal of System Simulation

Abstract: Building computer generated force model is a very important job in combat simulation. Its core content is modeling of complicated human behavior, including cognition behavioral modeling and physical behavioral modeling. The credibility is vital for behavioral model. Verification and validation (V&V) in all life circle of behavioral modeling can insure the credibility of behavioral model. On the basis of explaining V&V of behavioral modeling and other conceptions, the process model of behavioral modeling is proposed. The V&V process of CGF behavioral modeling is studied emphasizly. Many effective V&V methods for CGF behavioral modeling are explored.

Refined Alignment Method For Single-Axis Rotary Inertial Navigation Based On Fuzzy Adaptive Filtering, Hu Jie, Xiaozhu Shi

Journal of System Simulation

Abstract: In order to restrain the influence of saw tooth velocity error caused by the inertial measurement unit (IMU) rotation on the initial alignment accuracy of single-axis rotary strapdown inertial navigation system (SINS), a refined alignment method based on fuzzy adaptive Kalman filtering is proposed. After calculating the ratio of actual covariance to theoretical covariance of the innovation sequence, the method adaptively adjusts the measurement noise covariance matrix by using the fuzzy inference system (FIS), so that it can adapt to the changes of measurement noise caused by IMU rotation. The initial alignment validation experiments under the swing environment …

Research On Virtual Avatar Position And Orientation Technology For Augmented Reality Virtual Sandbox, Tiantian Yu, Xiaoping Wang, Weiqing Li, Zhiyong Su

Journal of System Simulation

Abstract: When using augmented reality (AR) virtual sandbox for multi-person collaborative command or discussion, the local operator needs to know the specific direction and location of the remote operator to avoid wrong direction, position conflict and to better communicate with the other. Aiming at this problem, a three-dimensional marker suitable for AR environment is designed, and a vision-based position and orientation algorithm is researched and implemented. The PnP algorithm is used to estimate the pose of the marker, and the area ratio method is used to calculate the azimuth. The experimental results show that the proposed algorithm can achieve …

Flight Simulation Modeling Method Based On Improved Euler Angle Formula, Lishan Jia, Li Ang

Journal of System Simulation

Abstract: Aiming at the singularity problem of common full flight motion equation, a modeling method based on improved Euler angle formula is proposed. On the basis of the modified small perturbation modeling equation, this method increases the influence of aircraft maneuvering surface on the aircraft Euler angle and a variable step solution algorithm is used. The model can overcome the singularity problem of common Euler equation, and the accuracy of model calculation is higher than other flight simulation models which overcome the singularity of Euler equation. Compared with the flight simulation model using the conventional Euler angle formula, the proposed …

An Intelligent Method For Rapid Construction Of Time Sensitive Target Strike Chain, Jiabo Lu, Peixing Cheng, Huang Yi, Jinqiang Yao, Xuemeng Yang, Xinqiang Ma, Liu Yong

Journal of System Simulation

Abstract: In order to improve the construction efficiency of the time sensitive hit chain, optimize the resource allocation in combat, and realize an intelligent method for quickly constructing the time-sensitive strike chain, the simulated annealing algorithm and genetic algorithm are adopted to build a time sensitive hit chain. Simulation experiments show that the method can complete the time sensitive target strike priority sorting, sensor platform-target pairing and weapon platform-target pairing in a short time, and destroy the target within the target time window. The proposed method optimizes the application of sensors and weapons, compensates for the limitations of constructing time-sensitive …

Sliding Mode Adaptive Synchronization Control Dual Master Dual Slave Teleoperation System, Lingyan Hu, Shiqiang Li, Fu Yun

Journal of System Simulation

Abstract: Aiming at the relative coordinated motion of the two-slave arms' end poses in the dual-master dual-slave teleoperation system, the influence on the coordinated positional relationship of the two slaves is analyzed when one of the master-slave controls is disturbed. A feasible synchronous position control method is propose which enables both the master-slave position error and the synchronization error of the dual master dual slave remote operating system to converge to zero during the coordinated motion When the master-slave arm moves along the desired trajectory, the coordination and synchronization of the movement between the two slave arms are ensured, and …

Simulation Experiment Of Quantum Ranging Process Based On The “Mozi” Quantum Satellite, Cong Shuang, Shiqi Duan

Journal of System Simulation

Abstract: The simulation experiment researches about two key processes of earth-satellite quantum ranging process are carried out, including the transmission and reception about the photon pairs based on the acquisition, tracking and pointing (ATP) system, and the calculation about the time difference of arrival (TDOA) of entangled photon pairs by the coincidence counting principle. Motion trajectory of the quantum satellite “Mozi” based on its six orbital parameters and the acquisition, tracking and pointing process to the optical signal from satellite to ground users are simulated. The function and structure of the acquisition tracking and pointing system are analysed, and a …

Ar-Based Simulation Interaction And Human Factor Assessment For Human Robot Cooperation Assembly Planning, Wang Qiang, Xiumin Fan, Qichang He, Wenmin Zhu

Journal of System Simulation

Abstract: To improve assembly efficiency, it has become a trend for traditional manual assembly workstations to be carried out human-robot collaboration transformation. To realize the safe and fast evaluation of the improvement scheme, a general human-robot collaboration simulation method and human factor evaluation method based on Augmented Reality are proposed. Four levels of human-robot collaboration assembly simulation are established. An interactive scheme between real human and virtual robot for visual detection, perception and feedback is established. A fuzzy comprehensive evaluation model of human physiological and psychological indicators for workstation design is constructed. The prototype system is developed. Taking the assembly …

Study On The Scattering Echo Signal Simulation Method Of Sea Scene For Wide-Band Phased Array Radar, Guijie Diao, Ni Hong, Yang Liang, Ningbo Gong, Guo Jiao

Journal of System Simulation

Abstract: Aiming at the problem of fast and accurate simulation of sea -scene scattering echo for wide-band phased array radar in radio frequency simulation, an efficient calculation method is proposed based on the time-domain approximation and frequency-domain transform. The frequency-domain transform method is used to calculate the scattering echo signal accurately, and the time-domain approximation method is used to calculate the echo signal of the large area of sea-clutter background. Then the scattering echo signal for wide-band phased array radar of the sea-scene is generated through vector summation. The simulation results validate this hybrid method. It shows that this hybrid …

Infrared Image Segmentation Of Aircraft Skin Based On Otsu And Improved I-Ching Divination Evolutionary Algorithm, Kun Wang, Ji Yao, Peilun Liu, Wang Li

Journal of System Simulation

Abstract: Infrared thermal imaging non-destructive testing is one of the commonly used methods for aircraft skin detection. Aiming at Otsu's large computational complexity and poor real-time performance, an aircraft skin infrared image segmentation method based on Otsu and an improved I-Ching divination evolutionary algorithm (IDEA) is proposed. The roulette selection operator is improved by using roulette selection for the I-Ching map of state size 3n, from which the n individuals with the maximum fitness values are then selected as new populations. The experimental results show that the proposed algorithm is superior to several other improved optimization algorithms both in terms …

Simulation And Analysis For Gaussian Jitter Effects Of Geosynchronous Satellite, Yulun Li, Yang Wei, Jiayi Guo

Journal of System Simulation

Abstract: Ultrahigh-spatial-resolution and high-temporal-revisit appear to be realizable for future space-borne imaging missions. By taking advantage of satellites on the geosynchronous orbit, the wide-area continuous monitoring capacity to ground target zones becomes possible. Focus on the imaging target displacement, it is necessary to study the platform jitter during the conceptual modeling phase. Discrete Event System Specification (DEVS) is employed to abstract the observation area as an event generator. The attitude stabilization is digitalized and both theoretical analysis and simulation experiments of Gaussian-excited signals are provided. Simulation results show that the distributions of attitude responses preserve the normality. The offset distance …

Three-Dimensional Adaptive Neural Network Guidance Law Against Maneuvering Targets, Yujie Si, Xiong Hua, Zhe Li

Journal of System Simulation

Abstract: The problem of designing a three-dimensional nonlinear guidance law accounting for saturation nonlinearity is concentrated to attack maneuvering targets. To solve the physical constraints of missile actuators, an anti-disturbance and anti-saturation terminal sliding mode guidance law is provided based on radial basis functions neural networks and adaptive method. The guidance law is bounded and ensures that the system state is uniformly ultimately bounded. Compared with the traditional anti-saturation guidance law, it has the advantages of fast convergence speed and high precision. Numerical simulations are introduced to demonstrate the effectiveness and superiority of the designed composite guidance law in theory.

Simulation Of Adaptive Track Control Of Ship Bending In Inland River Curved Channel, Langxiong Gan, Changsheng Wu, Deng Wei, Yuanzhou Zheng, Chunhui Zhou

Journal of System Simulation

Abstract: In view of the complex flow characteristics and difficult maneuvering of ships in curved river section, combined with the characteristics of ship AIS trajectory and customary route, the intelligent track and heading control algorithm is adopted to realize the automatic control of ship's safe turning. Firstly, the research waters are selected and according to the rules of lane-dividing navigation, the ship's turning track is reasonably planned. Then the ship motion simulation software is constructed, and the self-adaptive fuzzy PID course controller is designed by combining the self-adaptive fuzzy control algorithm and traditional PID control, the simulation of …

Correction Method Of Action Parameters Of Panzer Virtual Force Tactical Confrontation, Gao Ang, Xiaolu Wang, Zhiming Dong, Guohui Zhang

Journal of System Simulation

Abstract: Aiming at the problem of unreasonable virtual force tactical confrontation action parameters in the simulation training of armored force equipment system, resulting in unsatisfactory training effects, the idea of estimating posterior probability with prior probability is adopted to correct the parameters. According to the OODA theory, the tactical confrontation movement of armored forces is decomposed and an index system of influencing factors is constructed; the parameter collection method is proposed to establish the Bayesian network correction model and to realize dynamic adjustment; the expected optimization algorithm and the principal component analysis method are used to process the training data …

Negative Influence Minimization Algorithm For Social Networks, Yang Yi, Chunxiao Wu, He Ming, Zhou Bo

Journal of System Simulation

Abstract: While positive information is spreading in social networks, there is still a large amount of negative information spreading in the network. Aiming at the fact that there is few researches on suppressing the spread of negative information, a negative influence minimization algorithm for social networks is proposed. When negative information appears in social networks and some initial nodes are infected, the behavior of nodes propagating information depends on its coordination game with neighbor nodes. The objective function with minimal influence is used to find the K optimal blocking nodes, and finally the size of the final infected node is …

Robust Inference Of Kinase Activity Using Functional Networks, Serhan Yılmaz, Marzieh Ayati, Daniela Schlatzer, A. Ercüment Çiçek, Mark A. Chance, Mehmet Koyutürk

Computer Science Faculty Publications

Mass spectrometry enables high-throughput screening of phosphoproteins across a broad range of biological contexts. When complemented by computational algorithms, phospho-proteomic data allows the inference of kinase activity, facilitating the identification of dysregulated kinases in various diseases including cancer, Alzheimer’s disease and Parkinson’s disease. To enhance the reliability of kinase activity inference, we present a network-based framework, RoKAI, that integrates various sources of functional information to capture coordinated changes in signaling. Through computational experiments, we show that phosphorylation of sites in the functional neighborhood of a kinase are significantly predictive of its activity. The incorporation of this knowledge in RoKAI consistently …

Ft-Cnn: Algorithm-Based Fault Tolerance For Convolutional Neural Networks, Kai Zhao, Sheng Di, Sihuan Li, Xin Liang, For Full List Of Authors, See Publisher's Website.

Computer Science Faculty Research & Creative Works

Convolutional neural networks (CNNs) are becoming more and more important for solving challenging and critical problems in many fields. CNN inference applications have been deployed in safety-critical systems, which may suffer from soft errors caused by high-energy particles, high temperature, or abnormal voltage. Of critical importance is ensuring the stability of the CNN inference process against soft errors. Traditional fault tolerance methods are not suitable for CNN inference because error-correcting code is unable to protect computational components, instruction duplication techniques incur high overhead, and existing algorithm-based fault tolerance (ABFT) techniques cannot protect all convolution implementations. In this paper, we focus …

Optimizing Large-Scale Hyperparameters Via Automated Learning Algorithm, Bin Gu, Guodong Liu, Yanfu Zhang, Xiang Geng, Heng Huang

Machine Learning Faculty Publications

Modern machine learning algorithms usually involve tuning multiple (from one to thousands) hyperparameters which play a pivotal role in terms of model generalizability. Black-box optimization and gradient-based algorithms are two dominant approaches to hyperparameter optimization while they have totally distinct advantages. How to design a new hyperparameter optimization technique inheriting all benefits from both approaches is still an open problem. To address this challenging problem, in this paper, we propose a new hyperparameter optimization method with zeroth-order hyper-gradients (HOZOG). Specifically, we first exactly formulate hyperparameter optimization as an A-based constrained optimization problem, where A is a black-box optimization algorithm (such …

Identification Of Lsb Image Steganography Using Cover Image Comparisons, Michael Pelosi, Chuck Easttom

Journal of Digital Forensics, Security and Law

Steganography has long been used to counter forensic investigation. This use of steganography as an anti-forensics technique is becoming more widespread. This requires forensic examiners to have additional tools to more effectively detect steganography. In this paper we introduce a new software concept specifically designed to allow the digital forensics professional to clearly identify and attribute instances of LSB image steganography by using the original cover image in side-by-side comparison with a suspected steganographic payload image. This technique is embodied in a software implementation named CounterSteg. The CounterSteg software allows detailed analysis and comparison of both the original cover …

Backup And Recovery Mechanisms Of Cassandra Database: A Review, Karina Bohora, Amol Bothe, Damini Sheth, Rupali Chopade, V. K. Pachghare

Journal of Digital Forensics, Security and Law

Cassandra is a NoSQL database having a peer-to-peer, ring-type architecture. Cassandra offers fault-tolerance, data replication for higher availability as well as ensures no single point of failure. Given that Cassandra is a NoSQL database, it is evident that it lacks the amount of research that has gone into comparatively older and more widely and broadly used SQL databases. Cassandra’s growing popularity in recent times gives rise to the need of addressing any security-related or recovery-related concerns associated with its usage. This review paper discusses the existing deletion mechanism in Cassandra and presents some identified issues related to backup and recovery …

Non-Transgenic Crispr-Mediated Knockout Of Entire Ergot Alkaloid Gene Clusters In Slow-Growing Asexual Polyploid Fungi, Simona Florea, Jolanta Jaromczyk, Christopher L. Schardl

Computer Science Faculty Publications

The Epichloë species of fungi include seed-borne symbionts (endophytes) of cool-season grasses that enhance plant fitness, although some also produce alkaloids that are toxic to livestock. Selected or mutated toxin-free endophytes can be introduced into forage cultivars for improved livestock performance. Long-read genome sequencing revealed clusters of ergot alkaloid biosynthesis (EAS) genes in Epichloë coenophiala strain e19 from tall fescue (Lolium arundinaceum) and Epichloë hybrida Lp1 from perennial ryegrass (Lolium perenne). The two homeologous clusters in E. coenophiala—a triploid hybrid species—were 196 kb (EAS1) and 75 kb (EAS2), and …

Social Media User Relationship Framework (Smurf), Anne David, Sarah Morris, Gareth Appleby-Thomas

Journal of Digital Forensics, Security and Law

The use of social media has spread through many aspects of society, allowing millions of individuals, corporate as well as government entities to leverage the opportunities it affords. These opportunities often end up being exploited by a small percentage of the user community who use it for objectionable or unlawful activities; for example, trolling, cyber bullying, grooming, luring. In some cases, these unlawful activities result in investigations where swift retrieval of critical evidence required in order to save a life.

This paper presents a proof of concept (PoC) framework for social media user attribution. The framework aims to provide digital …

Application Of Guided Local Search (Gls) In Portfolio Optimization, Collether John

Tanzania Journal of Science

Portfolio optimization is a major activity in any operating business. Conventional portfolio optimization research makes simplifying assumptions; for example, they assume no constraint in how many assets one holds (cardinality constraint). They also assume no minimum and maximum holding sizes (holding size constraint). Once these assumptions are relaxed, conventional methods become inapplicable, and hence new methods are needed to tackle this challenge. Threshold Accepting is an established algorithm in the extended portfolio optimization problem. In this paper, an algorithm called Guided Local Search (GLS) is applied using an accurate and efficient designed hill climbing algorithm, named HC-C-R. GLS sitting on …