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Operations Research, Systems Engineering and Industrial Engineering

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Articles 3691 - 3720 of 3973

Full-Text Articles in Systems Science

Multi-Algorithm And Multi-Population Co-Optimization Differential Evolution Algorithm, Jinghua Zhang, Han Pu Jan 2019

Multi-Algorithm And Multi-Population Co-Optimization Differential Evolution Algorithm, Jinghua Zhang, Han Pu

Journal of System Simulation

Abstract: Algorithm fusion or co-evolutionary with multi populations are the solutions for complex engineering application. A multi-algorithm and multi-population collaborative optimization algorithm is proposed by differential evolution (DE) algorithm, which pays emphasis on algorithm selection and combination. The algorithm designs a parameter-adaptive DE algorithm and selects three different DE algorithm variants which is complementary for each other and provides a multi-population co-optimization scheme according to four algorithms characters. Stimulation results show that the proposed algorithm could make four different algorithms remedy for each other, gets a better result, and raises the precision, reliability and suitability, which reduces algorithm selection difficulty …


Adaptive Real-Time Tracking Control System For Ammonia Desulphurization, Lixin Ma, Mengyuan Lü Jan 2019

Adaptive Real-Time Tracking Control System For Ammonia Desulphurization, Lixin Ma, Mengyuan Lü

Journal of System Simulation

Abstract: In the ammonia desulphurization system, we can use forecast devices to compensate the delay time of sensor in the process of detection. But the error of the parameters in the mathematical model of the method has a great influence on the performance of the control system. So it is unable to realize the real-time tracking of the load. Concerning this problem, we put forward a kind of real-time tracking control system based on model reference adaptive technology which could be able to track the load—model reference adaptive technology is used in the ammonia desulphurization technology. It breaks the normal …


Detailed Enhancement Of Forward Vehicle Video Images Based On Structured Forest, Weidong Jin, Yanhua Hu, Tang Peng, Li Wei Jan 2019

Detailed Enhancement Of Forward Vehicle Video Images Based On Structured Forest, Weidong Jin, Yanhua Hu, Tang Peng, Li Wei

Journal of System Simulation

Abstract: In view of the complexity of existing image enhancement methods, which cannot highlight the detection target, this paper proposes a method for detail enhancement of forward vehicle video based on structured forest. This method is mainly divided into two parts: structured forest edge detection and visual enhancement. This paper implements the detail edge extraction and enhancement of the patrolling image of the catenary. The gray histogram distribution after processing is more balanced, and the difference between the average values of gray levels in the detail area and background area of the enhanced patrol image is the standard deviation. The …


Channel Modeling And Networking Simulation Of Full Duplex Communication, Zhimin Liu, Sun Jie, Jiarui Ding Jan 2019

Channel Modeling And Networking Simulation Of Full Duplex Communication, Zhimin Liu, Sun Jie, Jiarui Ding

Journal of System Simulation

Abstract: Full duplex communication is a new wireless communicating technology for improving the spectrum efficiency substantially. Few researches study full duplex networking technology now nationally and internationally. The architecture and implementation approach of full duplex communication system are introduced to describe the main model and functions of the platform in detail. After analyzing different kinds of self-interference cancellation technology, the self-interference cancellation module and channel model of full duplex system in the platform is built based on C language,which lays a foundation for prospective full duplex networking technology. Simulation results verify the platform’s effectiveness, and present the spectrum efficiency and …


Prediction Model Of Coke Quality Based On De-Bp Neural Network, Wenhua Tao, Zhengbo Yuan Jan 2019

Prediction Model Of Coke Quality Based On De-Bp Neural Network, Wenhua Tao, Zhengbo Yuan

Journal of System Simulation

Abstract: The quality of coke has a great effect on the furnace process. In order to solve the problem of large amount of calculation and inspection of coke quality prediction linear method, the coke quality prediction model based on DE-BP neural network is established on the basis of analyzing the factors affecting coke quality, which uses principal component analysis method to determine the parameters of the input vector with the coal and coke ash quality indicators Ad, sulfur Std, crushing strength M40, abrasion resistance M10 as the output vector prediction. The result of …


Prediction Model For Breakdown Voltage Of Transformer Oil Based On Relative Transformation And Kernel Principal Component Analysis, Yinguo Xiong Jan 2019

Prediction Model For Breakdown Voltage Of Transformer Oil Based On Relative Transformation And Kernel Principal Component Analysis, Yinguo Xiong

Journal of System Simulation

Abstract: Aiming at the difficulty of measuring the breakdown voltage of transformer oil on line, a new prediction model for breakdown voltage of transformer oil is proposed based on relative transformation (RT) and kernel principal component analysis (KPCA). By analyzing the factors that are closely related to the breakdown voltage, the original data space is converted to the relative data space by relative transformation to improve the distinguishability between data. KPCA is employed in the relative space for the purpose of data dimension reduction, denoising and extracting nonlinear features. Kernel principal components extracted by KPCA are used as the input …


Simulation And Analysis Of Blasting Effect For Multi-Core Tube-Hollow-High-Rise Building, Tiejun Cui, Shasha Li, Laigui Wang Jan 2019

Simulation And Analysis Of Blasting Effect For Multi-Core Tube-Hollow-High-Rise Building, Tiejun Cui, Shasha Li, Laigui Wang

Journal of System Simulation

Abstract: In order to study the complex high-rise building structure collapse process and effect of blasting, the blasting simulation of building containing multi-core tube and hollow structure are performed. Simulation building has hollow-four core tube-frame structure and the core tube throughout the whole building. Particle flow method is used to model the building, and blasting simulation is implemented using the blast algorithm based on particle flow. According to the structure characteristics and the distance of core tube and architecture center, the implementation of blasting is three groups design. The processes of blasting and the blasting results are analyzed. Results show …


Simulation Of Neighbor Discovery Algorithm In Directional Antenna Ad Hoc Networks Based On Opnet, Li Mo, Zhao Liang Jan 2019

Simulation Of Neighbor Discovery Algorithm In Directional Antenna Ad Hoc Networks Based On Opnet, Li Mo, Zhao Liang

Journal of System Simulation

Abstract: Neighbor discovery problem in directional antenna Ad Hoc networks is studied. A Q-Learning neighbor discovery algorithm is proposed, and a simulation model for directional antenna Ad Hoc networks based on OPNET software is setup. This algorithm makes a decision of transmitting and receiving mode for every neighbor scanning without the information of neighbor position through the Q-Learning mechanism. The reward value is determined according to the current scanning result, and the experiences are learned in order to improve the neighbor discovery efficiency. The simulation model based on OPNET software is constructed using three-layer modeling mechanism. Then the directional antenna …


Simulation Of Transient Temperature Field Of Current-Carrying Sliding Friction Pair, Fengyi Guo, Hongxin Gao, Liu Shuai, Zhiyong Wang, Zhang Kai, Aijun Wang Jan 2019

Simulation Of Transient Temperature Field Of Current-Carrying Sliding Friction Pair, Fengyi Guo, Hongxin Gao, Liu Shuai, Zhiyong Wang, Zhang Kai, Aijun Wang

Journal of System Simulation

Abstract: The transient temperature rise of pantograph and catenary system could affect material properties of the friction pair, which accelerates the wear of system. In order to reduce the wear caused by temperature, transient temperature and distribution of copper/copper-carbon friction pair are studied. A simulation model is established by using COMSOL Multiphysics software. Model effectiveness is verified with temperature experiments. The transient process of temperature field is studied by simulation. The results show that the temperature rise of carbon plate has small cyclical peaks. The highest temperature appears on the contact region in the initial stage of running. Temperature gradient …


Design And Study Of Forest Fire Forecasting Based On Pso And Ga-Bp Neural Network, Shuhua Bai, Mingxing Kuang Jan 2019

Design And Study Of Forest Fire Forecasting Based On Pso And Ga-Bp Neural Network, Shuhua Bai, Mingxing Kuang

Journal of System Simulation

Abstract: This paper collects the 2013-2015 meteorological data of four stations (Nanchang, Jingdezhen, Gi’an, Ganzhou) in Jiangxi province, and the corresponding forest fire danger grading, to establish a neural network fire prediction model. Corresponding network model is built respectively by adopting the genetic algorithm, particle swarm optimization (PSO) algorithm and particle swarm genetic hybrid algorithm to optimize the BP neural network. By comparing the prediction results of BP network, GA-BP network, PSO-BP network and PSO-GA-BP network with the experiments data, it shows that the PSO-GA-BP network prediction model is of higher accuracy, the PSO and GA enjoy the best …


Simulation Method Of Electromechanical Coupling Of Slot Antenna Based On Mesh Transmission, Wang Yong, Ren Dan, Dandan Wang, Xuexiao Zheng Jan 2019

Simulation Method Of Electromechanical Coupling Of Slot Antenna Based On Mesh Transmission, Wang Yong, Ren Dan, Dandan Wang, Xuexiao Zheng

Journal of System Simulation

Abstract: Electromechanical coupling involves mechanical and electromagnetic interaction, and data transfer between different physical fields is the key to the electromechanical coupling simulation. An efficient and accurate method based on mesh transmission to analyze the electromechanical coupling of slot antenna is presented. Force analysis of antenna is achieved by ANSYS and the interface program is written by APDL language. The deformed mesh generated by force analysis is obtained and outputted to hypermesh software to extract the deformed mesh surface. The surface mesh is imported into the electromagnetic field analysis software FEKO to calculate the electromagnetic performance of the antenna. The …


Design Of Real-Time Digital Baseband Simulator For Spatial Information Networks, Jianfeng Liu, Ma Shang, Zeguo Yang, Lixiang Liu, Jianhao Hu Jan 2019

Design Of Real-Time Digital Baseband Simulator For Spatial Information Networks, Jianfeng Liu, Ma Shang, Zeguo Yang, Lixiang Liu, Jianhao Hu

Journal of System Simulation

Abstract: The commonly used channel simulators always focus on the characteristics of RF signals at the receiver. However, they are costly in real-time simulation for spatial information network with multi-link and dynamic topology change. In this paper, a scalable simulator architecture for spatial information network, a simulation method for dynamic topology and channel propagation characteristics based on baseband data packages are presented. Based on this, a real-time spatial information networks simulation platform is designed and implemented. The platform can simulate the channel propagation delay, bit error, and dynamic topology changes for spatial information network. It supports 16 to …


Simulation Of Blade Erosion Of Variable-Pitch Axial Flow Fan, Chunxi Li, Zhang Dan, Xuemin Ye Jan 2019

Simulation Of Blade Erosion Of Variable-Pitch Axial Flow Fan, Chunxi Li, Zhang Dan, Xuemin Ye

Journal of System Simulation

Abstract: Affected by the performance of dust precipitators, significant differences of blade erosion regimes and erosion rates in induced draft fans are exhibited due to various particle diameters and concentrations. A 3D numerical simulation on a single-stage axial fan is carried out using Fluent to investigate the blade erosion regimes. The important features including particle trajectories under different particle diameters, erosion pattern and particle mass concentration distribution on the pressure and suction surfaces are examined, and the effect of particle mass concentration on erosion rate is analyzed. The results show that the erosion regimes are mainly affected by particle diameter. …


Neural Network Minimun Parameter Sliding Control Of Blood Pump Based On Heart Rate, Huibo Liu, Liu Mu Jan 2019

Neural Network Minimun Parameter Sliding Control Of Blood Pump Based On Heart Rate, Huibo Liu, Liu Mu

Journal of System Simulation

Abstract: An intelligent algorithm is designed to control the blood pump to assist natural cardiac blood pumping and to meet the needs of blood perfusion. The algorithm combines sliding mode control which does not depend on object model and RBF neural network which has optimal approximation properties to design controller. Minimum parameter learning method is used to design the adaptive law, adjust the weights of neural network. In order to ensure the real time, the speed signal is given by the function of blood flow, blood pump speed and heart rate. Through comparing with PID algorithm, the research shows that: …


Soft-Sensor Method Of Low Pressure Cylinder Exhaust Flow Of Heating Units, Tian Liang, Wang Tong Jan 2019

Soft-Sensor Method Of Low Pressure Cylinder Exhaust Flow Of Heating Units, Tian Liang, Wang Tong

Journal of System Simulation

Abstract: In order to improve the capacity of absorbing the wind power, power grid requests heating units to reduce the power load limit as far as possible. Turbine exhaust steam flow is a main parameter which determines power load limit. By analysing the balance of the mass-energy on vapor flow, and choosing the condensate flow and enthalpy rise of condensate and enthalpy drop of number 6 low pressure heater as auxiliary variables, soft-sensor method of low pressure cylinder exhaust flow is established. Furthermore, number 7 and number 8 extraction pressure and temperature are chosen simultaneously and dynamic low pressure cylinder …


Network Mode And Economy Analysis Of Photovoltaic-Battery System In Microgrid, Weiqing Sun, Liu Tong, Liu Bo, Youjia Wang Jan 2019

Network Mode And Economy Analysis Of Photovoltaic-Battery System In Microgrid, Weiqing Sun, Liu Tong, Liu Bo, Youjia Wang

Journal of System Simulation

Abstract: Due to its various power sources, flexible operation modes and ability of making full use of distributed energy resources, microgrid has received broad attention. Focusing on the two different network modes of photovoltaic-battery system (PVBS), the power flow distribution of photovoltaic-battery hybrid system (PVBHS) and photovoltaic-battery integrated system (PVBIS) under different operation conditions are analyzed separately and the corresponding operational economy calculation model is proposed. Using the life cycle cost (LCC) analysis method, the economy of PVBHS and PVBIS is compared. A 6-bus microgrid lab system and the IEEE 33-bus test system are taken as the study case. Results …


Research On Fault Detection And Isolation Method For Typical Hydraulic System, Lixia Zhang, Fuzhou Feng, Xiangbo Liu, Wang Min Jan 2019

Research On Fault Detection And Isolation Method For Typical Hydraulic System, Lixia Zhang, Fuzhou Feng, Xiangbo Liu, Wang Min

Journal of System Simulation

Abstract: The integrated transmission device possesses some inherent characteristics of the multiple working modes, discontinuity, multi-coupling, which lead to problems such as the fault detection difficulty and fault isolation inaccuracy. Analyzed in detail the structure and working principle of torque converter compensation circuit, the bond graph modeling and diagnosis methods were studied. Then the relationship between global analytical redundancy and fault characteristic matrix is established, which accurately accomplishes the fault detection and isolation. Finally, the rules between the analytical redundancy relations and different faults are verified by simulation experiments, which indicate that the design and application of FDI based on …


Orm-Dcsk: A Novel Dcsk Communication Scheme, Zhang Gang, Chuangang Wang, Guoquan Li, Jinzhao Lin Jan 2019

Orm-Dcsk: A Novel Dcsk Communication Scheme, Zhang Gang, Chuangang Wang, Guoquan Li, Jinzhao Lin

Journal of System Simulation

Abstract: To overcome the intra-signal interference components and the large average bit energy existing in decision variables, an improved RM-DCSK algorithm, named ORM-DCSK, is proposed. An orthogonal chaotic generator is designed to eliminate the intra-signal interference components. Besides, the signal frame format is expanded to reduce the average bit energy. The BER is derived and simulated in AWGN channel. The simulation results show that ORM-DCSK performs greatly better in BER performance than RM-DCSK algorithm without sacrificing transmission rate.


Prediction Of Alumina Density Based On Lssvm, Guimei Cui, Haijin Yang, Piliang Liu, Yu Kai Jan 2019

Prediction Of Alumina Density Based On Lssvm, Guimei Cui, Haijin Yang, Piliang Liu, Yu Kai

Journal of System Simulation

Abstract: The prediction model of alumina density based on the PSO algorithm with swarm activity to optimize LSSVM method is built. According to the production process characteristics of aluminum electrolysis and historical data, the input variables of the model is determined. It can solve these problems that Particle Swarm Optimization (PSO) algorithm is with the risk of premature convergence and least square support vector machine is time consuming with parameter selection. The method uses swarm activity as diversity index. When swarm activity is quickened to descend, evolution operation is added to modify the positions or velocities of particles to …


Study On Stability Of Bbmc Under Voltage And Current Control Mode, Xiaoping Zhang, Xiaoqiu Li, Wu Zhi Jan 2019

Study On Stability Of Bbmc Under Voltage And Current Control Mode, Xiaoping Zhang, Xiaoqiu Li, Wu Zhi

Journal of System Simulation

Abstract: In the paper, the stability of Buck-Boost matrix converter in voltage/current control mode is studied, and a nonlinear modeling and analysis method on the Buck-Boost matrix converter is proposed. The discrete iterative nonlinear mapping model of the converter is established. The influence of voltage feedback coefficient K1 and current proportional coefficient K2 on system stability is analyzed by sampling the distribution map of output voltage, hence, the stable domain of K1-K2 is determined. The influence on converter stability is verified and analyzed by the time domain waveform, the stroboscopic sampling chart and the …


Complete Coverage Belief Function Path Planning Algorithm Of Autonomous Underwater Vehiclebased On Behavior Strategy, Wenyang Gan, Daqi Zhu Jan 2019

Complete Coverage Belief Function Path Planning Algorithm Of Autonomous Underwater Vehiclebased On Behavior Strategy, Wenyang Gan, Daqi Zhu

Journal of System Simulation

Abstract: For the complete coverage path planning of autonomous underwater vehicle (AUV), a complete coverage belief function path planning algorithm based on behavior strategy is proposed by introducing the behavior strategy and using the concept of map belief function, which can make AUV accomplish the complete coverage and avoid obstacles automatically. The grid belief function is constructed based on environmental information, using different function values to distinguish between the obstacle, the covered and the uncovered grid. AUV selects the next navigation position by path planning strategy. Next navigation position is selected by behavior strategy if AUV navigates to the …


Gradient Descent Self-Tuning Control Of Flexible Space Manipulator After Capturing Operation, Cheng Jing, Chen Li Jan 2019

Gradient Descent Self-Tuning Control Of Flexible Space Manipulator After Capturing Operation, Cheng Jing, Chen Li

Journal of System Simulation

Abstract: The flexible vibration is generated after all-flexible space manipulator capturing a satellite, and the collision leads to unsteadiness of system. For the unstable composite system, the self-turning control algorithm based on hybrid trajectory is designed in this paper. The theory of gradient descent is used for parameter adaptive rate design to realize the real time adjustment of the PID control parameters. A supervised controller is designed through Lyapunov function to generate the stability and H tracking characteristic of the system. The hybrid trajectory is generated based on the concept of virtual force, which is used to accomplish …


Anchor Adaptive Movement Algorithm For Mobile Nodes Localization, Zhou Fei, Wennan Liu Jan 2019

Anchor Adaptive Movement Algorithm For Mobile Nodes Localization, Zhou Fei, Wennan Liu

Journal of System Simulation

Abstract: Location awareness is very important in mobile sensor networks. The existing methods mainly focus on the improvement based on the MCL (Monte Carlo Localization), few of them study the anchor path planning. However, anchors random movement usually causes the waste of energy and resource. Aiming at this deficiency, this paper adopts the grid benefit criterion and achieves anchors adaptive movement. Threshold instead of traversal method is used to reduce the amount of calculation and positioning time. In order to solve the anchors aggregation problem during adaptive movement, we divide the target area into four subareas and constrain part of …


Design And Implementation Of Human-Computer Interactive System For Public Information Service In Smart City, Han Feng, Xiaoling Li, Xiuwen Sun, Lingyu Ji Jan 2019

Design And Implementation Of Human-Computer Interactive System For Public Information Service In Smart City, Han Feng, Xiaoling Li, Xiuwen Sun, Lingyu Ji

Journal of System Simulation

Abstract: In view of the singleness on the interactive contents and forms of public information services in Smart City, we design and implement a human-computer interactive system. We analyze both user behavior characteristics as self-portrait effect, landing effect, honeypot effect and Smart City application design characteristics as socialization, intellectualization and humanization. Regarding these characteristics, we specify the interactive contents and the corresponding interactive forms and design the UI features for improving user experience. We research on the technologies involved in the implementation of the system, including gesture recognition based on segments, face recognition and resource integration using WPF, besides, holographic …


Characteristic Analysis Of Tri-Stable Stochastic Resonance With Levy Noise, Lifang He, Yingying Cui, Guoquan Li, Jinzhao Lin Jan 2019

Characteristic Analysis Of Tri-Stable Stochastic Resonance With Levy Noise, Lifang He, Yingying Cui, Guoquan Li, Jinzhao Lin

Journal of System Simulation

Abstract: The characteristic analysis of tri-stable stochastic resonance with Levy noise is analyzed deeply with Levy noise being combined with a tri-stable stochastic resonance system and average signal-to-noise ratio gain being used as index. The effect of tri-stable system parameters w, a, b and Levy noise intensity amplification factor D on the resonant output is explored with different Levy noise. Results show that for different distribution of Levy noise, the stochastic resonance phenomenon can be induced by tuning the system parameters. The parameter intervals which can induce stochastic resonances are approximately equal. Moreover, by adjusting the intensity …


Research On Fjsp Problem Of Invasive Weed Optimization Based On Hybrid Strategy, Li Ke, Wang Yan, Zhicheng Ji Jan 2019

Research On Fjsp Problem Of Invasive Weed Optimization Based On Hybrid Strategy, Li Ke, Wang Yan, Zhicheng Ji

Journal of System Simulation

Abstract: To solve the flexible job-shop scheduling problem more effectively, an improved invasive weed algorithm was proposed. A random key encoding scheme based on transformed sequences was proposed and an adaptive Gauss mutation operator was introduced to diversity the population in the process of weed breeding. In spatial diffusion stage, the standard deviation of normal distribution based on tangent function was used as seed’s new step size search method. In competition of invasive weed stage, by using the guided search strategy in the bee colony algorithm, the weed was guided to improve its ability to jump out of the …


Approach For Lithium-Ion Battery Rul Prognostics Based On Cpso-Rvm, Chaolong Zhang, Yigang He, Lifen Yuan Jan 2019

Approach For Lithium-Ion Battery Rul Prognostics Based On Cpso-Rvm, Chaolong Zhang, Yigang He, Lifen Yuan

Journal of System Simulation

Abstract: On account of the measured battery state of health (SOH) data are often subject to different levels of noise pollution, a battery remaining useful life (RUL) prognostics approach is presented based on wavelet denoising and CPSO-RVM in the paper. Wavelet denoising is performed twice with different thresholds in order to weaken the strong noise and remove the weak noise. Relevance vector machine (RVM) improved by chaos particle swarm optimization (CPSO) algorithm is utilized to estimate the trend of battery SOH variation trajectory and predict the battery RUL based on the denoised data. RUL prognostic experiments using battery data provided …


Evasive Maneuvers Against Missiles For Unmanned Combat Aerial Vehicle In Autonomous Air Combat, Xizhong Yang, Jianliang Ai Jan 2019

Evasive Maneuvers Against Missiles For Unmanned Combat Aerial Vehicle In Autonomous Air Combat, Xizhong Yang, Jianliang Ai

Journal of System Simulation

Abstract: For UCAV having the capability to deal with autonomous air combat, the flight dynamics model with the overload input and the 3-dimensional proportional navigation guidance model were established. Based on artificial neural network, an evasive maneuver decision was presented for avoiding incoming missiles. The degrees of freedom for UCAV-missile system were reduced by coordinate transformation, which simplified the complicated model as a non-linear model with relatively small amount of input and a single output. After the neural network samples were generated and trained, evasive results could be directly predicted from the relationship of positions between UCAV and missile …


Evaluation On Pilot Performance Of Detecting Runway Incursion Based On Visual Simulation, Kun Yang, Xiangyu Ge, Pengfei Ju, Bai Jie Jan 2019

Evaluation On Pilot Performance Of Detecting Runway Incursion Based On Visual Simulation, Kun Yang, Xiangyu Ge, Pengfei Ju, Bai Jie

Journal of System Simulation

Abstract: In order to evaluate the performance of pilots using HUD and PFD to detect runway incursion under approach and landing circumstances, a visual simulation system for transport category airplanes is designed by visual simulation technology. The system includes models of head up display (HUD), primary flight display (PFD), cockpit of transport category airplanes, 3-D terrain of airport. And a program is written to read flight joystick data to control flight. On this visual simulation system, performance experiment of pilots using HUD and PFD to detect runway incursion is carried out. Analysis results show that the response time of …


Numerical Simulation On Air Quality In The Boeing 737 Aircraft Cabin, Xiuyan Wang, Gewen Zhang, Yanmin Liu, Zongshuai Li, Jiaquan Lin Jan 2019

Numerical Simulation On Air Quality In The Boeing 737 Aircraft Cabin, Xiuyan Wang, Gewen Zhang, Yanmin Liu, Zongshuai Li, Jiaquan Lin

Journal of System Simulation

Abstract: The air quality in the cabin will directly affect the persons’ efficiency when an aircraft berths. In order to analyze the effect of velocity of air outlet of bridge-load air conditioning on the air quality of aircraft cabin, the first class cabin of Boeing 737 aircraft is used as the research object, based on the CFD method and numerical heat transfer theory, the air quality in aircraft cabin is simulated numerically. Based on PMV and CO2 relative concentration, a new air quality index (IAO) is put forward to evaluate the air quality of aircraft cabin, …