Position And Attitude Estimation Based On Combination Matching In Calibration Area,
2021
1. Aeronautical Engineering Institute, Jiangsu Aviation Technical College, Zhenjiang 212134, China;;2. Zhenjiang Key Laboratory of UAV Application Technology, Jiangsu Aviation Technical College, Zhenjiang 212134, China;
Position And Attitude Estimation Based On Combination Matching In Calibration Area, Cai Peng, Chaoping Shen, Hongyan Li
Journal of System Simulation
Abstract: Vision navigation technology of scene matching needs hardware to measure the distance and attitude of the camera. A method of position and attitude estimation based on the combination of feature points in the calibration area is proposed. The software can get the camera position and attitude of the real-time image by selecting the best set of Scale-Invariant Feature Transform(SIFT) feature matching points of the reference image calibration area of the real-time image, and calculating the local coordinates of the ground of SIFT feature matching points based on the triangle internal linear interpolation method, using space resection, avoids the defect …
High Adaptability Vehicle Network Communication Protocol Based On Aodv,
2021
1. College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China;;2. Key Laboratory of advanced ship communication and information technology, Harbin Engineering University, Harbin 150001, China;
High Adaptability Vehicle Network Communication Protocol Based On Aodv, Wang Tong, Gao Shan, Tianshu Dai
Journal of System Simulation
Abstract: Routing protocol is an essential part of vehicular ad-hoc network (VANET). According to the characteristics of frequent changes of vehicle node location in urban environment, an AODV routing protocol based on Network Topology Changes (NTCAODV) is proposed. According to the speed and relative position information, by calculating the stability coefficient of nodes, the link connection is established on the basis of principle of "optimal stability", and the idea of extended loop is improved according to recorded the link establishment time. Simulation results show that NTCAODV routing protocol has good performance in various urban environments, improves …
Evaluation Method On Multi-Stage Bayes Information Fusion For Scatters Hwil Simulation,
2021
Science and Technology on Special System Simulation Laboratory, Beijing Simulation Center, Beijing 100854, China;
Evaluation Method On Multi-Stage Bayes Information Fusion For Scatters Hwil Simulation, Yecheng Wang, Ma Jing, Congjun Jin, Jie Li, Bin Shi
Journal of System Simulation
Abstract: In order to simulate the complex 3D target in the RF HWIL (hardware in the loop simulation) system, the equivalence framework of multiple scattering centers of complex 3D target for three stages of outfield test data, mathematics simulation data and HWIL data are introduced. Using the pre-test information as each stage for transmission, evaluation method is designed by multi-stage Bayes information fusion for HWIL simulation. Based on prior information of outfield test data and mathematics simulation data, by using Bayes information fusion theory, the average data reconstruction of each stage is obtained and compared and high reliability …
Collaborative Optimization Of Ship Stowage Plan And Yard Container Unloading For Container Terminal,
2021
1. School of Mechanical Automation, Wuhan University of Science and Technology, Wuhan 430081, China;;
Collaborative Optimization Of Ship Stowage Plan And Yard Container Unloading For Container Terminal, Zhixiong Liu, Hanwen Qian, Jialan Yan
Journal of System Simulation
Abstract: Stowage plan is an important component of the operation production for the container terminal, which directly affects the handling efficiency and shipping safety. The aim is minimizing the total reloading numbers of both the yard and the ship bay, in view of the constraint of ship heeling moment and loading for light upon heavy, the model is employed for collaborative optimization of stowage plan and yard unloading for multiple destination ports and multiple bays. The hybrid evolutionary strategy algorithm is adopted with the local search algorithm. As to ship stowage play for multiple bays, a heuristic rule for the …
Transmission Process Prediction Of Novel Coronavirus Based On System Dynamics,
2021
School of Information, Beijing Wuzi University, Beijing 101149, China;
Transmission Process Prediction Of Novel Coronavirus Based On System Dynamics, Xuepeng Lu, Shang Jiao, Junhui Zhao, Lulu Lü, Zhou Li
Journal of System Simulation
Abstract: The transmission characteristics of novel coronavirus is considered and a new SE4IR2 model based on the principle of system dynamics is proposed. The US epidemic data from June to November is used to set the isolation rate and other parameters, and the SE4IR2 model is used to fit, analyze and predict the development of the epidemic trend in the next stage. The empirical part uses the data from June to November in the United States to achieve the parameters of the SE4IR2 model, obtains the parameter values in December and January through the time series prediction model, and compares …
Research On Simulation Experiment Support Technology For Complex Sos Of Live And Constructive Symbiosis,
2021
1. Joint Operations College, National Defense University, Beijing 100091, China;;
Research On Simulation Experiment Support Technology For Complex Sos Of Live And Constructive Symbiosis, Wu Xi, Ma Jun
Journal of System Simulation
Abstract: The technology of simulation experiment for System of Systems (SoS) is very important in research of complex SoS. The operation SoS is typical complex SoS.Based on the concept of parallel system, symbiotic simulation, digital twin, etc., the main characteristics of the technology are summarized. Focus on the architecture of complex system simulation experiment environment, the experiment environment architecture, hybrid simulation driving mechanism and virtual real data access mode are studied. A feasible method is provided to carry out the complex SoS experiment of multi domain joint, data fusion, resource integration and human-computer integration, and the comprehensive application of …
Research On Control Strategy Of Isolated Ac-Dc Matrix Converter Under Input Unbalance,
2021
College of Information Engineering, Xiangtan University, Xiangtan 411105, China;
Research On Control Strategy Of Isolated Ac-Dc Matrix Converter Under Input Unbalance, Wenlang Deng, Li Yong, Hongbin Pan
Journal of System Simulation
Abstract: To reduce the active power fluctuation of the isolated AC-DC matrix converter (IAMC) under the input unbalance and to suppress the resonance of the LC filter, a deadbeat direct power control strategy based on active damping is proposed. The strategy uses the grid-side current and its delay component to calculate the IAMC input side filter capacitor voltage, which eliminates the high-precision voltage sensor of traditional active damping control, reduces the hardware cost, without the rotation coordinate transformation and phase-locked loops, so the calculation cost is small. The simulation results show that the proposed control strategy can effectively …
Fast Maritime Simulator Scene Modeling Method Based On Aerial Images,
2021
1. School of Navigation, Wuhan University of Technology, Wuhan 430063, China;;2. Hubei Key Laboratory of Inland Shipping Technology, Wuhan 430063, China;;
Fast Maritime Simulator Scene Modeling Method Based On Aerial Images, Lijia Chen, Wang Kai, Shigang Li, Yanfei Tian
Journal of System Simulation
Abstract: Artificial Modeling using Computer Aid Design software are frequently applied in maritime simulator scene modeling,but with low accuracy, low efficiency and complicate workflow. It's not the ideal method of modeling a large-scale area. A modeling method is proposed based on aerial images in combination with tilt photography modeling, procedural modeling and image semantic segmentation method. It's a fast and highly automated modeling method specially for the maritime simulator. A water area near Tianxingzhou Yangtze River Bridge is chosen as the model. Experiment results show that the proposed method is of fast speed, high precision, high degree of automation, …
Networked Simulation And It's Development Trend,
2021
College of Systems Engineering, National University of Defense Technology, Changsha 410073, China;
Networked Simulation And It's Development Trend, Duan Hong, Xiaogang Qiu
Journal of System Simulation
Abstract: Carrying out simulating whenever and wherever possible as well as the large-scale trend of simulation lead to the demand of networked simulation.. Through the changes of range, from model interconnection, experimental collaboration and domain simulation collaboration, three layers of meanings of networked simulation are analyzed; The characteristics of networked simulation are summarized from five aspects, pattern, application, target, focus, and morphology. The idea that the networked simulation will bring changes to the simulation application of the activity scope and method, resource construction, resource verification, organizational structure, and so on is proposed. By sorting out the development process …
Numerical Simulation Of Aerodynamic Characteristics For Double-All-Wing Unmanned Aerial Vehicle Based On Computational Fluid Dynamics Theory,
2021
1. No.1 School, Naval Aviation University, Yantai 264001, China;;
Numerical Simulation Of Aerodynamic Characteristics For Double-All-Wing Unmanned Aerial Vehicle Based On Computational Fluid Dynamics Theory, Kuizhi Yue, Zhang Yuan, Liangliang Cheng, Dazhao Yu
Journal of System Simulation
Abstract: Follow the rapid progress of the nation's blue ocean strategic projection capability of sea power, an Unmanned Aerial Vehicle (UAV) with double-all-wing configuration is studied to match the trend. The UAV is conceptually designed by CATIA software, the aerodynamic characteristic of the model is numerically simulated by computational fluid dynamics (Computational Fluid Dynamics, CFD) theory, and the performance of the UAV to take off from the aircraft carrier is also analyzed. The lift coefficient, drag coefficient and lift-drag ratio of the double-all-wing UAV model with a angle of attack of 0 can reach 0.596 2, 0.037 6 and 15.824 …
Simulation Evaluation For Service Facilities Distribution And Flow Lines Optimization On Urban Rail Transfer Station,
2021
1. College of Traffic and Transportation, Beijing Jiaotong University, Beijing 100044, China;;
Simulation Evaluation For Service Facilities Distribution And Flow Lines Optimization On Urban Rail Transfer Station, Liu Feng, Chunfu Shao, Hongfei Jia, Chunjiao Dong
Journal of System Simulation
Abstract: The rationality of passenger flow lines design and service facilities distribution inside urban rail transfer station directly affects the passenger's transfer efficiency. The Simulation technology are used to evaluate the station's transfer efficiency, and the optimal plan can be proposed, which can not only avoid the crowded passenger flow, but also improve the efficiency. The features of peak passenger flow are considered, the service level of the passenger's stay time is given, the change of congested area's passenger flow density is expressed in the form of time-varying chart. Combined with the overall chart of the average passenger flow density, …
Research On A Dynamically Perceptive Connectivity Restoration Method,
2021
1. College of Electronic Information Engineering, Xi'an Technological University, Xi'an 710021, China;;2. Northwest Institutes of Advanced Technology, Xi'an Technological University, Xi'an 710021, China;
Research On A Dynamically Perceptive Connectivity Restoration Method, Hua Xiang, Baohua Li, Hongjuan Yao, Wang Zhao, Jiaxian Zuo
Journal of System Simulation
Abstract: The cluster communication network has the characteristics of time-varying topology, strong node mobility, and unstable link status, etc. It is difficult to maintain a stable topology. The network is divided into disconnected subgroups. In order to solve the communication problem between different groups, the cooperative relay node is introduced and a dynamic-sensing connection recovery method is proposed. A cooperative communication model is built and the mathematical expression of link quality indicators is deduced, which designs a multi-objective link evaluation function and achieves the optimal relay location planning through a multi-objective connectivity recovery algorithm. Simulation results show that the …
Simulation And Optimization Of Supersonic Drag Characteristics Of Blunt Cone Ascender,
2021
1. Computer Network Information Center, Chinese Academy of Sciences, Beijing 100190, China;;2. University of Chinese Academy of Sciences, Beijing 100049, China;;
Simulation And Optimization Of Supersonic Drag Characteristics Of Blunt Cone Ascender, Xiazhen Liu, Yuan Wu, Li Qi, Zhao Rui, Zhang Jian, Zhonghua Lu
Journal of System Simulation
Abstract: Reducing shock drag is an important objective of the aerodynamic optimization of Mars ascenders. The CFD(Computational Fluid Dynamics) method is used to study the supersonic drag characteristics of a typical blunt cone ascender. Under the design constraints of slenderness ratio of 0.42, 13 groups busbar shape set of zero-lift drag are compared, and the longitudinal static and dynamic stability are discussed. The research results show that, under the design constraints, the blunt shape with large bulbous and a gently sloped conical surface has low drag characteristics. The reason is that, after passing through the bulbous, the supersonic airflow …
Optimization Of Urban Metro-Based Underground Logistics System Network With Hub-And-Spoke Layout,
2021
1. College of Defense Engineering, Army Engineering University of PLA, Nanjing 210001, China;;
Optimization Of Urban Metro-Based Underground Logistics System Network With Hub-And-Spoke Layout, Ren Rui, Wanjie Hu, Jianjun Dong, Zhilong Chen
Journal of System Simulation
Abstract: Dual application of passenger commuting and underground logistics based on urban metro (M-ULS) provides a solution for traffic congestion. A three-stage optimization approach for the hub-and-spoke M-ULS network is proposed. An Entropy-TOPSIS model for underground flow screening was established based on indicators of freight flows unity, order priority and regional accessibility, considering facility capacity constraints, a location-allocation-routing combinatorial model with construction and operation costs objectives is proposed, Set Coverage Exact Algorithm, Adaptive Immunity Clone Selection Algorithm and Floyd-Warshall Algorithm are developed. Geographic information statistics of Nanjing is applied as the benchmark for real-world simulation. Results show that the modeling …
Graph-Theoretic Partitioning Of Rnas And Classification Of Pseudoknots-Ii,
2021
CUNY College of Staten Island
Graph-Theoretic Partitioning Of Rnas And Classification Of Pseudoknots-Ii, Louis Petingi
Publications and Research
Dual graphs have been applied to model RNA secondary structures with pseudoknots, or intertwined base pairs. In previous works, a linear-time algorithm was introduced to partition dual graphs into maximally connected components called blocks and determine whether each block contains a pseudoknot or not. As pseudoknots can not be contained into two different blocks, this characterization allow us to efficiently isolate smaller RNA fragments and classify them as pseudoknotted or pseudoknot-free regions, while keeping these sub-structures intact. Moreover we have extended the partitioning algorithm by classifying a pseudoknot as either recursive or non-recursive in order to continue with our research …
Knot Theory In Virtual Reality,
2021
Western Kentucky University
Knot Theory In Virtual Reality, Donald Lee Price
Masters Theses & Specialist Projects
Throughout the study of Knot Theory, there have been several programmatic solutions to common problems or questions. These solutions have included software to draw knots, software to identify knots, or online databases to look up pre-computed data about knots. We introduce a novel prototype of software used to study knots and links by using Virtual Reality. This software can allow researchers to draw links in 3D, run physics simulations on them, and identify them. This technique has not yet been rigorously explored and we believe it will be of great interest to Knot Theory researchers. The computer code is written …
A Machine Learning Approach To Understanding Emerging Markets,
2021
University of Arkansas, Fayetteville
A Machine Learning Approach To Understanding Emerging Markets, Namita Balani
Graduate Theses and Dissertations
Logistic providers have learned to efficiently serve their existing customer bases with optimized routes and transportation resource allocation. The problem arises when there is potential for logistics growth in an emerging market with no previous data. The purpose of this work is to use industry data for previously known and well-documented markets to apply data analytic techniques such as machine learning to investigate the uncertainty in a new market. The thesis looks into machine learning techniques to predict miles per stop given historical data. It mainly focuses on Random Forest Regression Analysis, but concludes that additional techniques, such as Polynomial …
Awegnn: Auto-Parametrized Weighted Element-Specific Graph Neural Networks For Molecules.,
2021
University of Kentucky
Awegnn: Auto-Parametrized Weighted Element-Specific Graph Neural Networks For Molecules., Timothy Szocinski, Duc Duy Nguyen, Guo-Wei Wei
Mathematics Faculty Publications
While automated feature extraction has had tremendous success in many deep learning algorithms for image analysis and natural language processing, it does not work well for data involving complex internal structures, such as molecules. Data representations via advanced mathematics, including algebraic topology, differential geometry, and graph theory, have demonstrated superiority in a variety of biomolecular applications, however, their performance is often dependent on manual parametrization. This work introduces the auto-parametrized weighted element-specific graph neural network, dubbed AweGNN, to overcome the obstacle of this tedious parametrization process while also being a suitable technique for automated feature extraction on these internally complex …
Step-Wise Deep Learning Models For Solving Routing Problems,
2021
Singapore Management University
Step-Wise Deep Learning Models For Solving Routing Problems, Liang Xin, Wen Song, Zhiguang Cao, Jie Zhang
Research Collection School Of Computing and Information Systems
Routing problems are very important in intelligent transportation systems. Recently, a number of deep learning-based methods are proposed to automatically learn construction heuristics for solving routing problems. However, these methods do not completely follow Bellman's Principle of Optimality since the visited nodes during construction are still included in the following subtasks, resulting in suboptimal policies. In this article, we propose a novel step-wise scheme which explicitly removes the visited nodes in each node selection step. We apply this scheme to two representative deep models for routing problems, pointer network and transformer attention model (TAM), and significantly improve the performance of …
Frameaxis: Characterizing Microframe Bias And Intensity With Word Embedding,
2021
Singapore Management University
Frameaxis: Characterizing Microframe Bias And Intensity With Word Embedding, Haewoon Kwak, Jisun An, Elise Jing Jing, Yong-Yeol Ahn
Research Collection School Of Computing and Information Systems
Framing is a process of emphasizing a certain aspect of an issue over the others, nudging readers or listeners towards different positions on the issue even without making a biased argument. Here, we propose FrameAxis, a method for characterizing documents by identifying the most relevant semantic axes (“microframes”) that are overrepresented in the text using word embedding. Our unsupervised approach can be readily applied to large datasets because it does not require manual annotations. It can also provide nuanced insights by considering a rich set of semantic axes. FrameAxis is designed to quantitatively tease out two important dimensions of how …
