Engineering Commons^™

Method For Modulation Recognition Of Radar Signals In Complex Environment, Jiang Li, Guoqing Zhao, Li Lin

Journal of System Simulation

Abstract: As the increasing application of intra-pulse modulations, modulation recognition of radar signals becomes difficult in radar reconnaissance systems. Usually, there are multipath interferences along with the intercepted signal. The conventional methods become slowdown because of the multipath interferences. Aiming at radar signals in multipath channel, a feature extraction method was proposed based on higher order ambiguity function (AF) and singular vector decomposition, adopting the linear support vector machine (SVM) classifier to determine the types of the intercepted radar signals. Theoretical analysis and simulation results show that the proposed method has good ability to suppress the influence of multipath interferences …

Semi-Naive Bayesian Forecasts Rainfall On Cloud Platform, Shengjun Xue, Peiyun Zhang, Jingyi Chen

Journal of System Simulation

Abstract: Rainfall forecast has played an increasingly important role of meteorological services. As cloud platform can improve the efficiency and accuracy of rainfall forecast, it has been applied to forecast rainfall. The recent forecast methods require the independence between all the attributes, but most of the meteorological factors are interdependent, which reduces the accuracy of the prediction. Consequently, a semi-naive Bayesian classification was proposed combined with fuzzy set theory realizing it on cloud platform. At the same time, to improve the accuracy and the efficiency of rainfall forecast, a forecast model was established, which used the historical weather data …

Joint Optimization Control Of Energy Storage System Management And Demand Response, Xueying Gao, Tang Hao, Gangzhong Miao, Zhaowu Ping

Journal of System Simulation

Abstract: The joint optimization problem of energy management and demand response were studied in order to reduce the long-run cost of electricity users equipped with energy storage unit and smart applications, and to increase their benefits meanwhile. The goals were achieved by controlling both the energy storage unit (charging, discharging, or idle) and the load service (access or delay). Based on the random nature of solar photovoltaic, load demand electricity and electricity price, the joint optimization problem was modeled as infinite-horizon Markov decision process model, and Q-learning algorithm was proposed to find the optimal solution. Simulation results show that the …

Grid Side Power Factor Control Strategy For Matrix Converter, Guo Hai, Quan Yue, Sun Wen, Zhiping Fan

Journal of System Simulation

Abstract: Since input filter is usually ignored in the modulation strategy for matrix converter, only the input current of converter is controlled in the same phase with grid voltage. Phase advance of grid current will come about as a result of current of capacitor and the power factor of grid side will be reduced. To solve this problem, the mathematical model of matrix converter was analyzed and the relationship between the real power factor and parameters of the system was studied. A grid current closed-loop control strategy was proposed. As the control objective of the strategy, the grid current was …

Tunable Compact Thz Devices Based On Graphene And Other 2d Material Metasurfaces, Tianjing Guo

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Since the isolation of graphene in 2004, a large amount of research has been directed at 2D materials and their applications due to their unique characteristics. Compared with the noble metal plasmons in the visible and near-infrared frequencies, graphene can support surface plasmons in the lower frequencies of terahertz (THz) and midinfrared. Especially, the surface conductivity of graphene can be tuned by either chemical doping or electrostatic gating. As a result, the idea of designing graphene metasurfaces is attractive because of its ultra-broadband response and tunability.

It has been demonstrated theoretically and experimentally that the third-order nonlinearity of graphene at …

Fluid Network Modeling Method Based On Theory Of Signal Flow Graph, Zhang Yue, Han Pu

Journal of System Simulation

Abstract: The concept of signal flow graph was introduced into the mechanism modeling process to describe the fluid network. Various structures in the fluid network were classified as node and branch, and establish the algorithm relationship between node pressure and bransh resistance. Aiming at the characteristics of nonlinear and strong coupling of fluid network, the node pressure was expressed by Taylor series near the quiescent operation point using the linear model to describe the nonlinear network. A method was proposed which used the directed graph to improve the computational efficiency of the admittance matrix at the working point. Based on …

Harmony Gravitational Search Algorithm For Solving The Problem Of Parameter Estimation For Fractional-Order Chaotic Systems, Huang Yu, Jiarong Wang, Weiping Liang

Journal of System Simulation

Abstract: Aiming at parameter estimation for fractional-order chaotic systems, a harmony gravitational search algorithm was proposed. The particles, which were updated by gravitational search algorithm, were recreated and searched through memory selections and probability search in harmony search algorithm. At the same times, in order to solve the problem that the speed changed too fast when the particles closed to the optimal solution, the partial adjustment probability was set to non-linearly decrease with the adsorption capacity increasing. Standard test functions were used to test the algorithm, and the test results show that the algorithm has good stability and global search …

Hybrid Quantum-Behaved Particle Swarm Optimization For Parameter Identification Of Dfig, Yingying Jiang, Zhicheng Ji

Journal of System Simulation

Abstract: In order to ensure the accuracy of the doubly-fed wind power generator (DFIG) and improve the control performance of the generator, a hybrid quantum-behaved particle swarm optimization for parameter identification was proposed. A parameter identification model of DFIG at coordinate was established. Quantum-behaved particle swarm optimization (QPSO) was improved and then mixed with simulated annealing (SA) algorithm. The proposed algorithm was compared with particle swarm optimization (PSO), QPSO and improved QPSO, which were applied to parameter identification of DFIG in Matlab/Simulink. Simulation results show that the proposed algorithm can improve the identification accuracy of …

General Hils System Research Of Mi-171 Helicopter Autopilot, Renwei Hu, Guo Nan, Kong Xia, Peng Jun, Chuanwei Sun

Journal of System Simulation

Abstract: A general analogous and digital Hardware-In-the-Loop-Simulation (HILS) system was built for AΠ-34Б autopilot of Mi-171 helicopter. Simulator of avionics signals with hybrid interface for both analogous and digital signals was developed. A nonlinear flight dynamics mathematical model was built for Mi-171 helicopter. And on-ground test condition was built for analogous and digital flight control system. Test of on-ground system simulation and aerial flight were done by referring to Flight Test Outline. Results of flight test indicate that all classifications satisfy criteria at once, and the test results of aerial and on-ground are in good concordance …

Cell Voltage Optimization Of Aluminum Electrolysis Based On Neural Network-Genetic Algorithm, Chenhua Xu, Li Zhi

Journal of System Simulation

Abstract: In order to reduce the production cost of electrolytic aluminum, an optimization extreme method was proposed based on neural network and genetic algorithm, to find the optimal production cell voltage and the corresponding production conditions. Using kernel principal component analysis method to determine the key parameters affecting of aluminum electrolysis production, a neural network model of electrolytic aluminum was established. Using the genetic algorithm, the global optimal value of the cell voltage of the electrolytic aluminum and the corresponding production conditions were found. The simulation results show that the neural network and genetic algorithm can predict the cell …

Simulation Study Of Grid-Side Improved Control Strategy For Direct-Driven Wind Turbine Under Unbalanced Faults, Wang Dan, Chongru Liu, Gengyin Li

Journal of System Simulation

Abstract: In order to reduce the power and DC voltage fluctuations of direct-driven wind turbine under unbalanced grid faults, an integrated and improved control strategy for grid-side converter was proposed. In the analysis of grid-side power characteristics, positive and negative sequence components of grid-side voltage and current were calculated by converting them to the same reference frame and a compensation control loop to simultaneously restrain the second harmonic components of active and reactive power was designed on the basis of quasi proportional resonant control. Moreover, to reduce DC-link overvoltage, a feed-forward modified component reflecting the active power error between the …

Microscopic Online Simulation Method Of Road Traffic Accident Emergency Disposal, Peiqun Lin, Jiahui Liu, Kaibin Yao

Journal of System Simulation

Abstract: An online simulation based decision making method was proposed to search for the comparatively optimal emergency disposal plan quickly and quantitatively after the traffic accident, and the evaluation index of traffic emergency disposal plans was proposed on the foundation of designing the process and framework of the online simulation, and the vehicle movement model applied to highway traffic accident was established. The online simulation based decision making system was developed using VISSIM-COM interface, and it has been applied to a typical highway of Guangdong Province. The simulation and the practical application results illustrate that multiple emergency disposal plans …

Simulation Study Of Ac/Dc Converter For Marine Medium Voltage Test Power System, Kun Xia, Zhang Shuo, Yuan Yin, Zhang Ping

Journal of System Simulation

Abstract: In order to realize the simulation of marine medium voltage power system of 40kW capacity in laboratory, it is necessary to convert AC 380V of generators outputs to the stable 4kV DC output. Two level transformations were applied in the system. The bridgeless boost PFC circuit was applied in AC/DC conversion in front. Four roads of full bridge PWM converters in cascade mode were applied to boost the voltage in DC/DC conversion at the end. One of them was the phase-shift full bridge to achieve the control of adjusting voltage output. The other three bridges were common full bridge …

Cpcw Design And Performance Analysis For Mimo Radar, Shen Dong, Li Qiang, Liu Xin, Zhou Yu

Journal of System Simulation

Abstract: Based on the good correlation and random property of chaotic phase coding waveform (CPCW), a method is proposed to increase the target detection performance of multiple-input multiple-output (MIMO) radar with CPCW. CPCW can be generated by uniform quantifying and quadriphase coding for chaotic sequences. Comparing the correlation property of four kinds of CPCW, the longer Tent phase coding waveform is chosen to increase the target detection performance of MIMO radar, especially for the close small target. Meanwhile, signal processing model is built by CPCW, and multiple pulse compression accumulation can help to reduce the cross-correlation and auto-correlation sidelobes of …

Comparison Of Object Detection And Patch-Based Classification Deep Learning Models On Mid- To Late-Seasonweed Detection In Uav Imagery, Arun Narenthiran Veeranampalayam Sivakumar, Jiating Li, Stephen Scott, Eric T. Psota, Amit J. Jhala, Joe D. Luck, Jiating Li

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Mid- to late-season weeds that escape from the routine early-season weed management threaten agricultural production by creating a large number of seeds for several future growing seasons. Rapid and accurate detection of weed patches in field is the first step of site-specific weed management. In this study, object detection-based convolutional neural network models were trained and evaluated over low-altitude unmanned aerial vehicle (UAV) imagery for mid- to late-season weed detection in soybean fields. The performance of two object detection models, Faster RCNN and the Single Shot Detector (SSD), were evaluated and compared in terms of weed detection performance using mean …

Optimal Linear Moment Estimation Method For Gumbel Distribution, Yumei Zhai, Ruixing Zhao

Journal of System Simulation

Abstract: Linear moment is one of the important methods to estimate the extreme value distribution function in engineering practice. In order to improve the estimation performance for Gumbel distribution, the estimating results of twelve empirical distribution functions were simulated by using Monte Carlo method. The optimal linear moment estimation method was constructed based on the empirical distribution function with the minimum estimation error, and compared with ordinary moment, traditional linear moment and maximum likelihood method. The study shows that choosing an appropriate empirical distribution function can enhance the estimation accuracy. The optimal empirical distribution function varies depending on the sample …

Application Of Pso-Bp Algorithm In Hydraulic System Fault Diagnosis, Handong Zhang, Liusong Tao

Journal of System Simulation

Abstract: It is of great significance to monitor, forecast and diagnose hydraulic systems’ fault timely and accurately. First, this paper describes the basic fault model theoretical knowledge of BP neural neystem failure neural network modeling has created and simulated. PSO-BP neural network has been raised, this paper has established PSO optimize model of the BP neural system fault diagnosis. BP network has been created and simulated in Plunger pump hydraulic system failure. The correct results indicate that this mixed PSO-BP algorithm is better than the improved BP algorithm, and can meet the requirements of Hydraulic system fault diagnosis.

User Interface Design For Mobile Financial Services: Users Perspective, Belachew U. Regane

African Conference on Information Systems and Technology

Users belonging to different countries have different exposure and perception to trust the technology to adopt it. Users’ trust and adoption rates are challenging issues in mobile financial services. Thus, the purpose of the research is how to design a trustful user interface. Market research is conducted to collect data. Using the data, personas and use cases developed. The result of personas and use cases used to develop prototypes. Prototype A and B designed differently to give choice to users to investigate users' trust. Prototype A is designed to make it easy to use and clear workflow. Whereas prototype B …

Usability And Accessibility Model For E-Government Websites In Ethiopia, Yoseph Zeleke

African Conference on Information Systems and Technology

The development of websites and portals are main components of the e-Government strategy implementations for the last nine years in Ethiopia. However, services optimizations with usability and accessibility are key issues of Ethiopia e-Government services development.

Therefore, the ultimate goal of this study is creation of usable, accessible and sustainable Ethiopian eGovernment websites with four stage of research analysis, through proposed model. The investigations results are used to provide a clear picture of what needs to be improves from management and user point of views and also from other stakeholders of e-Government services. This study applies mixed methods of data …

A Comprehensive Study For Modern Models: Linking Requirements With Software Architectures, Sisay Yemata

African Conference on Information Systems and Technology

Several models recently have been addressed in software engineering for requirements transformation. However, such transformation models have encountered many problems due to the nature of requirements. In the classical transformation modeling, some requirements are discovered to be missing or erroneous at later stages, in addition to major assumptions that may affect the quality of the software. This has created a crucial need for new approaches to requirements transformation. In this paper, a comprehensive study is presented in the main modern models of linking requirements to software architectures. An extensive evaluation is conducted to investigate the capabilities of such modern models …

Artificial Intelligence Towards Future Industrial Opportunities And Challenges, Gizealew Dagnaw

African Conference on Information Systems and Technology

The industry 4.0 will bring reflective changes to our society, including an important digital shift in the manufacturing sector. At present, several manufacturing firms are trying to adopt the practices of industry 4.0 throughout their supply chain. The Fourth Industrial Revolution and the artificial intelligence at its core are fundamentally changing the way we live, work and interact as citizens. The complexity of this transformation may look overwhelming and to many threatening. Recently, the dramatic growth of new generation information technologies has prompted several countries to seek new strategies for industrial revolution. The globalization and the competitiveness are forcing companies …

Efficient Data Mining Algorithm Network Intrusion Detection System For Masked Feature Intrusions, Kassahun Admkie, Kassahun Admkie Tekle

African Conference on Information Systems and Technology

Most researches have been conducted to develop models, algorithms and systems to detect intrusions. However, they are not plausible as intruders began to attack systems by masking their features. While researches continued to various techniques to overcome these challenges, little attention was given to use data mining techniques, for development of intrusion detection. Recently there has been much interest in applying data mining to computer network intrusion detection, specifically as intruders began to cheat by masking some detection features to attack systems. This work is an attempt to propose a model that works based on semi-supervised collective classification algorithm. For …

It Governance For Balancing Evolveability And Standardization In Health Information System Implementation In Ethiopian Context, Birkinesh Lagebo, Birkinesh Lagebo, Mark Gaynor Prof., Temtim Assefa Dr

African Conference on Information Systems and Technology

Failing to balance standardization and evolveability in IS design and implementation process results sustainability failure which is common in developing country. IS research provides various IS design solution including layered modular architecture to address both evolveability and standardization simultaneously. However, this design solution requires appropriate IT governance mechanisms which lacks both theoretical and empirical explanation in IS research. The core of this research is understanding IT governance mechanism design that can balance standardization and evolveability in the course of IS design and implementation. The research uses the case of District Health Information System-2 (DHIS-2), layered modular architecture, design and implementation …

Energy Conservation And Emissions Reduction Policy Simulation About Energy-Consuming Enterprises, Yongbo Yang, Chen Ying, Yang Jing, Mingzhong Liu, Zhenchao Jiang, Zeng Rong

Journal of System Simulation

Abstract: Energy conservation and emissions reduction policy have made some achievements, at the same time there are still some problem such as too much administrative command, lack of market mechanism and the lack of price mechanism. The government is both energy conservation leader, supervisor also rule makers. In order to formulate energy conservation policy, they must have overall cognition on energy conservation and emissions reduction. The dynamic relationship between the government, enterprise and environment was analyzed setting up simulation model for key energy-consuming enterprises based on system dynamics. Through the simulation, the influence of different policies for energy conservation …

Spring Unit Equivalent Model Of Steam Turbo-Generator Radial Fixture, Shouqun Sun, Huifang Wei, Haihui Xu

Journal of System Simulation

Abstract: The fixed structure of turbo-generator stator end was studied. Bottom-up modelling method was applied to establish the finite element model. The method calculating the combined stiffness of the connection structure and effective contact area was proposed, which used conical symmetric mid plane. Combined with spring-damper unit, insulated screw was analysed by finite element simulation. The stator winding end as a whole system was for modal analysis. Corresponding natural frequency and vibration model were acquired. Hammering test method and modal testing system were applied to calculate the steam turbine end natural frequency. Compared with the experimental result, the text given …

Sigma Point Kalman Filters For Re-Entry Ballistic Target Tracking, Chunling Wu, Yongfeng Ju, Hu Ping, Chengdong Duan

Journal of System Simulation

Abstract: A new kind of sigma-point Kalman filter was proposed, quadrature Kalman filter(QKF), for the purpose of re-entry ballistic target tracking applications. The new filter linearized the nonlinear functions using statistical linear regression method through a set of Gaussian-Hermite quadrature points that parameterized the Gaussian density. The simulation experiment compared this new sigma point filter with EKF, DDF and UKF. Simulation results show that the estimation errors of all sigma point filters are all lower than that of EKF. The estimation error of QKF is lower than that of UKF, and its filtering credibility is almost same as that of …

Coral Reefs Optimization For Solving Parameter Identification In Permanent Magnet Synchronous Motor, Yawei Quan, Tian Na, Zhicheng Ji, Wang Yan

Journal of System Simulation

Abstract: High accuracy identification of parameters in permanent magnet synchronous motor (PMSM) is the basis of controller design. According to the drawbacks of slow speed, big error, and small number of parameters in classical particle swarm optimization (PSO) and least square method, Coral Reefs Optimization (CRO) was proposed to solve the parameter identification problem in PMSM. In order to improve the identification accuracy, the parameter setting in CRO was adjusted. The mathematical model of PMSM in coordinate system was established, CRO, PSO and RLS were applied to identify parameters in PMSM, and were verified in Matlab/Simulink for comparison. The simulation …

Impact Analysis On Distribution Prediction Of Stipa Species Under Climate Change, Xuqing Tang, Jianlin Li

Journal of System Simulation

Abstract: Based on the actual climatic data from 1981 to 2000 in Northeast China, the predicted climatic data and the actual distribution data of Stipa species, 12 climatic factor indicators affecting Stipa species distribution were extracted combining with similar biological and ecological characteristics of Stipa. By introducing Gauss Competitive Exclusion Principle and the statistical analysis method, a competitive stochastic mathematical model of the distribution of Stipa was built, and the corresponding algorithm was given. The forecast figures were obtained for the optimal, medium and general adaptable distribution of the five Stipa species from 2041 to 2050 and from 2091 …

Multi-Channels Converged Communication Method In Mobile Terminals Based On Virtual Link, Wenqiang Yao, Kaisheng Xu, Feng Jie, Yanqin Zhu, Lingzhi Li

Journal of System Simulation

Abstract: In the region overlapping multiple radio signals such as 3G/4G and Wi-Fi, the mobile terminal usually only chooses one of sigals to transmit data. It limits the access bandwidth of the mobile terminal, influences the upper applications running on the devices, and increases the costs of data communication. A new multi-channels converged communication method was proposed according to the analysis of existing technology. The method used the virtual link receiving all the packets sent by upper applications, and sent the packets simultaneously in multi-channels according to the status of every physical channel. The specific implementation processes were given about …

Mixed H2/H∞ Optimal Pid Control For Superheated Steam Temperature System, Weiping Liang, Jiarong Wang

Journal of System Simulation

Abstract: Aiming at the non-linear, large inertial, uncertain parameters and multi-disturbances of the main steam temperature object in power plants, a mixed H₂/H_∞ optimal PID control scheme was designed. The multiplicative perturbed boundary of the H_∞ and the effective range of the PID controller parameters were given under the system being closed-loop stability. An improved gravitational search algorithm was proposed in order to obtain optimum performance indicators. The effectiveness of the algorithm was supported through testing on typical test functions, then the algorithm was applied to optimize the parameters of the main steam temperature system Mixed …