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2020

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Articles 931 - 960 of 1664

Full-Text Articles in Numerical Analysis and Scientific Computing

Research On Sparse Grid Non-Uniformity Correction Technologies For Infrared Imaging Resistor Array, Huijie Du, Hongming Zhao, Yu Hong, Gao Yang, Zhang Yi Jul 2020

Research On Sparse Grid Non-Uniformity Correction Technologies For Infrared Imaging Resistor Array, Huijie Du, Hongming Zhao, Yu Hong, Gao Yang, Zhang Yi

Journal of System Simulation

Abstract: The non-uniformity characteristic is the crucial factors affecting the image quality projected by infrared imaging resistor array, and which affects the fidelity of the infrared scene simulation. The non-uniformity characters of the infrared imaging simulation resistor array were analyzed based on measured data; the sparse grid and the flood non-uniformity correction technologies were investigated and analyzed and based on the existing measuring technology the improved sparse grid method for engineering was proposed. Through measuring the non-uniformity data, establishing the linear look-up table and correcting the non-uniformity image, the non-uniformity correction algorithm was developed and validated. The result shows …


Soa-Based Network-Centric Software Architecture For Warfare Simulation Applications, Wendi Cheng, Chu Wei Jul 2020

Soa-Based Network-Centric Software Architecture For Warfare Simulation Applications, Wendi Cheng, Chu Wei

Journal of System Simulation

Abstract: For the difficulty of integrating heterogeneous resource and low reuse rate by task-oriented development model in the traditional electronic information system, this article proposes a service-oriented simulation software constructing method. By information registration, publication, subscription, distribution and other network-centric core services to build a global service bus for dynamic scheduling, we can improve information sharing capabilities. By the standard descriptions and specifications, we can make flexible reorganization of business services. In a loosely coupled way to integrate the system between the service provider and service requester, we can format a service-oriented system development platform, which can provide support …


Overall-Wind-Speed Dynamic Sliding Mode Power Control For Direct-Driven Pmsg-Based Wind Energy Generation System, Aihua Wu, Buhui Zhao, Jingfeng Mao Jul 2020

Overall-Wind-Speed Dynamic Sliding Mode Power Control For Direct-Driven Pmsg-Based Wind Energy Generation System, Aihua Wu, Buhui Zhao, Jingfeng Mao

Journal of System Simulation

Abstract: A novel dynamic sliding mode control (DSMC) strategy for direct-driven PMSG system was proposed to improve wind energy generation efficiency in overall-wind-speed operating condition. Based on the multi-stage working characteristics, optimum torque control method was adopted to implement the MPPT task when wind speed was under the rating value, and power control method was adopted to implement the constant power generation task when wind speed was above the rating value. The controller was designed by the sliding mode reaching law method of power exponent function. Due to the switch function amplitude feedback, the switch gain was granted the …


Compensation For Auv’S Navigation Algorithm Based On Virtual Noise Model, Menglong Cao, Feifei Li, Xintao Liu Jul 2020

Compensation For Auv’S Navigation Algorithm Based On Virtual Noise Model, Menglong Cao, Feifei Li, Xintao Liu

Journal of System Simulation

Abstract: The simultaneous localization and mapping (SLAM) of Autonomous underwater robot (AUV) is the key technology to realize the auto navigation for robot in the unknown environment of underwater, and it is one of the hot topics in the field of robotics research. In the framework of autonomous underwater robot SLAM, extended kalman filter (EKF) was applied to achieve the SLAM. For the model linearization errors and unknown noise statistics, EKF algorithm was used based on virtual noise compensation technology. This method could make the unknown model error into the virtual noise, and use the noise statistical to estimate the …


Research On Magnetic Device Model Of Nonlinear Inductance Combined With Transformer And Inductor, Hongzhu Li, Jiayue Sun, Qingjie Qi, Wang Qiao Jul 2020

Research On Magnetic Device Model Of Nonlinear Inductance Combined With Transformer And Inductor, Hongzhu Li, Jiayue Sun, Qingjie Qi, Wang Qiao

Journal of System Simulation

Abstract: A modeling method of magnetic device combining transformer and inductance was put forward. The modeling method reflects characteristics of magnetic and electric circuit simultaneously, and reflects parasitic parameters with capacitance. And the physical concepts of parameters are clear in the model. The interface model reflecting magnetic and electric circuit was established through ideal transformer based on electromagnetic theory, and nonlinear inductance simulation model reflecting hysteresis effect through derivation was obtained. The hysteresis loop of inductance actual simulation and that from magnetic core manual agreed well, proving the correctness and effectiveness. By modeling method in the proposed magnetic device, coupling …


Performance Evaluation Of Bayesian Estimator With Consistency Validation, Zuolei Sun, Li Ying, Zhang Bo, Zhang Wen Jul 2020

Performance Evaluation Of Bayesian Estimator With Consistency Validation, Zuolei Sun, Li Ying, Zhang Bo, Zhang Wen

Journal of System Simulation

Abstract: Considering the lack of sound evaluation method for Bayesian estimator design, an approach employing consistency as the core criterion was proposed. By studying the unbiasedness and whiteness of innovation sequence yielded during observation update routine, the normalized innovations square (NIS) was constructed, and then the chi-square test being able to detect the Posterior's consistency was carried out on NIS. Experiments demonstrate that the proposed algorithm can identify the inappropriate parameter configuration for both linear and nonlinear systems, therefore the performance of the estimators can be evaluated.


Research On Credibility Of Function Validation To C2 System Of Land Force, Yaxin Tan, Yongchun Xia, Fan Rui, Haitao Zhi Jul 2020

Research On Credibility Of Function Validation To C2 System Of Land Force, Yaxin Tan, Yongchun Xia, Fan Rui, Haitao Zhi

Journal of System Simulation

Abstract: The function verification of C2 system of land force is a way to check its satisfaction level to real fighting in the system application. The verification is caught out after the force has received these equipment. In order to complete the verification, the environment with virtual force and real software was built by modeling and simulation method, so that the verification could be carried out under the condition which is similar to true combat. In this environment, the interaction between real human and virtual force by the C2 software could help to complete the verification. Focusing on the credibility …


Optimization Scheme Of Average Time For Finding Idle Channel In Cognitive Radio System, Qiao Pei, Liyuan Xiao, Yanyan Han, Gao Ling Jul 2020

Optimization Scheme Of Average Time For Finding Idle Channel In Cognitive Radio System, Qiao Pei, Liyuan Xiao, Yanyan Han, Gao Ling

Journal of System Simulation

Abstract: In cognitive radio system, periodic spectrum sensing was taken by secondary users to prevent the interference to primary users. Supposed that there are many primary user channels, when the current primary user occupies channel, secondary users do spectrum handover. During spectrum handover, the time of finding an idle channel is a random variable. In order to speed up spectrum handover, the system used equal gain combining cooperative spectrum sensing to inspect an idle channel. This pattern optimized the sensing time of the single user channel, in order to get the best effect of the average time in finding idle …


Mechanism For Green Multicast Routing Protection In Multi-Granularity Transport Networks, Junling Shi, Xingwei Wang, Huang Min Jul 2020

Mechanism For Green Multicast Routing Protection In Multi-Granularity Transport Networks, Junling Shi, Xingwei Wang, Huang Min

Journal of System Simulation

Abstract: A mechanism for green multicast routing protection was designed, where the constraint of quality of service (QoS), energy consumption and the survivability to single link or node failure were under consideration. The node model which supported the exchange of multi-granularity services was built to meet the energy saving requirement in multi-granularity services, and the analysis of energy consumption was introduced with the formulas of energy consumption defined. Based on the physical topology, a multi-layer auxiliary graph was proposed, which was used to allocate and release resources. The fuzzy mathematics method was used to present QoS by the membership degree. …


Evolutionary Game-Based Spectrum Sharing Scheme In Cognitive Radio Network, Huanhuan He, Xingwei Wang, Huang Min Jul 2020

Evolutionary Game-Based Spectrum Sharing Scheme In Cognitive Radio Network, Huanhuan He, Xingwei Wang, Huang Min

Journal of System Simulation

Abstract: In order to solve the waste of resources caused by the static spectrum allocation policy, cognitive radio technology can be used to dynamically and efficiently manage spectrum, and spectrum sharing becomes the key issue. To make secondary users to share spectrum fairly, an evolutionary game-based spectrum sharing scheme in cognitive radio network was proposed. Because cognitive radio network was dynamic and heterogeneous, the wireless channel was unreliable and affected by environment easily, the knowledge of fuzzy mathematics was introduced to characterize the parameters related to the secondary user satisfaction degree, and the Gas Brownian Motion Optimization algorithm was …


Study Of Model And Simulation On Ceramic Tile Polishing Energy Consumption, Haidong Yang, Chengdun Guo, Li Hong, Guosheng Liu, Jiawen Wu Jul 2020

Study Of Model And Simulation On Ceramic Tile Polishing Energy Consumption, Haidong Yang, Chengdun Guo, Li Hong, Guosheng Liu, Jiawen Wu

Journal of System Simulation

Abstract: Currently, there are many defects in the production line of ceramic polishing, such as over polishing and high energy consumption, so it is an urgent mission to optimize the technical processes in order to cut down the energy consumption. Material removal equations and energy usage model were established based on the kinematic mechanism process and Preston equation. Simulation experiments were done by the above equations and model, so as to depict the evolution in both quality and power consumption. The impact of transmission speed of belt, lateral swing speed, disc rotation speed and other kinematic parameters on over polishing …


Research On Modeling And Scheduling Of Cluster Tools With Reentrant Process, Chunrong Pan, Li Liang Jul 2020

Research On Modeling And Scheduling Of Cluster Tools With Reentrant Process, Chunrong Pan, Li Liang

Journal of System Simulation

Abstract: Cluster tools reconfigured are increasingly adopted in wafer fabrication. With single-wafer processing technology, the productivity and quality of semiconductor manufacturing have been improved. The configurations of cluster tools and constraints of operation processes were proposed. Due to the increase of processing requirements of wafer revisiting, the scheduling of cluster tools becomes more complicated. Thus, modeling, performance analyzing and scheduling of cluster tools with reentrant process were reviewed. Meanwhile, an illustrative example was given to show the feasibility of simulation scheduling. By analyzing the advantages and disadvantages of research methods available, approaches and future directions which would be effective for …


Robust Model And Optimization Of Anti-Impact Performance For Mems Ring Gyroscope, Jiang Tao, Sun Lin Jul 2020

Robust Model And Optimization Of Anti-Impact Performance For Mems Ring Gyroscope, Jiang Tao, Sun Lin

Journal of System Simulation

Abstract: In order to reduce the influence of parameter variation on anti-impact performance of micro mechanical gyroscope, a kind of MEMS ring gyroscopes was chosen as the research object, applying the method of explicit dynamic finite element analysis and design of experiment, influence of parameter variation was studied with significant analysis, and reasonable design parameters were decided. Mathematical model of anti-impact robustness optimization for ring gyroscope was established, in which maximum impact stress and performance variation were minimized as the optimal goal. Ultimately, the optimal solution set could be obtained by means of pareto multi-objective genetic algorithm. Simulation results show …


Gep Automatic Clustering Algorithm With Dynamic Penalty Factors, Chen Yan, Kangshun Li, Yang Lei Jul 2020

Gep Automatic Clustering Algorithm With Dynamic Penalty Factors, Chen Yan, Kangshun Li, Yang Lei

Journal of System Simulation

Abstract: Various problems such as sensitive selection of initial clustering center, easily falling into local optimal solution, and determining numbers of clusters, still exist in the traditional clustering algorithm. A GEP automatic clustering algorithm with dynamic penalty factors was proposed. This algorithm combines penalty factors and GEP clustering algorithm, and doesn't rely on any priori knowledge of the data set. And a dynamic algorithm was proposed to generate the penalty factors according to the distribution characteristics of different data sets, which is a better solution for the impact of isolated points and noise points. According to four dataset, penalty factors' …


Algorithms For Join Queries In Multiple Wireless Sensor Networks, Shangfeng Mo, Yongjian Fan, Xiaoliang Wang, Qingchun Yu, Yinglong Li Jul 2020

Algorithms For Join Queries In Multiple Wireless Sensor Networks, Shangfeng Mo, Yongjian Fan, Xiaoliang Wang, Qingchun Yu, Yinglong Li

Journal of System Simulation

Abstract: The perception layer of Internet of Things (IoTs) is mainly composed of Multiple Wireless Sensor Networks (MWSNs). Data query processing is a very important research area in MWSNs. Join queries can monitor similar network environments in different positions. In general join algorithm, each ordinary node sends its join attribute value to the database server. The database server finds out the result set which meets the join conditions. In distributed join algorithm, the ordinary nodes predict their filters of next round and the database server obtains the global, common filters. The nodes which meet the join conditions send their data …


Generate Network’S Disjoint Mps Based On Simevents Simulation, Tang Jian, Fuli Ai, Faming Shao, Jiaojiao Zhang Jul 2020

Generate Network’S Disjoint Mps Based On Simevents Simulation, Tang Jian, Fuli Ai, Faming Shao, Jiaojiao Zhang

Journal of System Simulation

Abstract: The disjoint MPs (Minimal Path sets) algorithm proposed was improved from the point of signal transmission. The CoA network was transformed into a corresponding signal network, which was composed of forward and backward transmitting paths. According to the basic principle of disjoint MPs algorithm, a set of signal transmitting and rewriting rules, including forward and backward processing rules, were designed to make the disjoint MPs could be generated by means of DES (Discrete Event Simulation). The basic realizing idea was studied in SimEvents, in which, the entities acted as the information carriers, and the nodes as the …


Novel Algorithm Of High-Speed Target Isar Imaging Based On Stretch Method, Wenmao Luo, Yingliu Cui Jul 2020

Novel Algorithm Of High-Speed Target Isar Imaging Based On Stretch Method, Wenmao Luo, Yingliu Cui

Journal of System Simulation

Abstract: The pulse compression result will be distorted while the target moves very fast and it cannot get right ISAR images. A novel algorithm based on chirp-Fourier transform was proposed to solve this problem. In the scheme, every echo’s differential frequency signal of stretch processing was calculated by chirp-Fourier transform to estimate the target’s location and speed, and the target’s precious speed could be averaged by the estimations during the whole dwell time. Then the penalty function could be constructed to eliminate the intra and inter-pulse motion, and it could get right ISAR images. Because the chirp-Fourier transform was …


Design And Realization Of Radar Warning Receiver Modeling System, Limin Liu, Cheng Cheng, Zhuangzhi Han Jul 2020

Design And Realization Of Radar Warning Receiver Modeling System, Limin Liu, Cheng Cheng, Zhuangzhi Han

Journal of System Simulation

Abstract: According to the structure of the mainstream modern airborne radar warning receiver, a modeling method of radar warning receiver simulation system was proposed, and it realized by SystemVue. The system consists of radar signal interception, parameter estimation and signal sorting, and pulse description words can be obtained at last. The application of sorting method based on detection of single source point in the system improves the robustness. Simulation results verify the scheme feasibility.


Robust Flexible Job Shop Scheduling Method With Machine Breakdowns, Guohui Zhang, Lihui Wu, Nie Li, Yongcheng Wang Jul 2020

Robust Flexible Job Shop Scheduling Method With Machine Breakdowns, Guohui Zhang, Lihui Wu, Nie Li, Yongcheng Wang

Journal of System Simulation

Abstract: There are many uncertain events in the actual production process of flexible job shop, which affect the normal production and scheduling to achieve objective. According to the factor of the machine breakdown, two robustness measures combined with flexible job shop scheduling characteristics were proposed. One is considered as the initial schedule and the actual schedule makespan deviation, the other one is considered as each machine idle time and work load. The genetic algorithm was used to solve the problem, and the two parts chromosome coding was designed to avoid generating the illegal solution. Through the establishment of the probability …


Single Sign-On Model Based On Trusted-Daa Connection, Xiaohui Yang, Lijun Jiang, Wang Hong, Siyuan Chang Jul 2020

Single Sign-On Model Based On Trusted-Daa Connection, Xiaohui Yang, Lijun Jiang, Wang Hong, Siyuan Chang

Journal of System Simulation

Abstract: Traditional single sign-on (SSO) models adopt SSL connections in the cloud computing environments, while there exist several problems such as certificates cannot be updated in time, certificate updating needs a third party CA, etc.. To solve above problems, TPM was introduced between cloud identity providers and cloud service providers, and a trusted DAA connection (T-D-SSL) was designed by adopting the DAA authentication method to implementation cross platform trusted authentication, secure channel establishment, and certificate updating operation. Combining with T-D-SSL, SAML2.0, and ID-FF1.2, a new SSO model of the cloud computing environments was proposed, which could make sure the system …


Simulation Research On Model Parameter Identification Based On Prediction Error, Hongquan Wu, He Chi, Zhang Ping, Shuen Wang, Hongqiang Wei, Chu Jin, Zhang Peng Jul 2020

Simulation Research On Model Parameter Identification Based On Prediction Error, Hongquan Wu, He Chi, Zhang Ping, Shuen Wang, Hongqiang Wei, Chu Jin, Zhang Peng

Journal of System Simulation

Abstract: Parametric differential method is often used to extract resistance coefficient in the process of trajectory simulation research for aerial bomb. The method exists following problems: high precise original data required and influenced by measurement error easily, which would cause serious error in identification result and even lead to the radiation during identification. In order to solve these problems, a method of extracting resistance coefficient based on prediction error was modeled. While coordinate was used as observations, simulation research of model parameter identification was carried out for some bomb. Precision of calculation for two models was calculated and analyzed …


Power Modeling And Simulation For D/A Network In R-C Hybrid Sar Adc, Xingyuan Tong, Zhang Yang Jul 2020

Power Modeling And Simulation For D/A Network In R-C Hybrid Sar Adc, Xingyuan Tong, Zhang Yang

Journal of System Simulation

Abstract: D/A conversion network of SAR (SAR: Successive Approximation Register) ADC was discussed. The energy model of the capacitor array in R-C hybrid D/A network was established by using MATLAB. With the combination of resistor string’s static power and capacitor array’s switching power, the power model of the R-C hybrid network in SAR ADC was proposed based on a 65nm CMOS process. Furthermore, by considering matching requirement for the passive components, 12-bit R-C hybrid D/A networks with “5+7”, “6+6” and “7+5” type of structures were simulated and compared. The research can provide significant guidance for circuit design and optimization of …


Research On Double-Sided Linear Induction Motor Of Electromagnetic Catapult Of Carrier-Based Aircraft, Xijun Liu, Kunlun Zhang, Guoqing Liu Jul 2020

Research On Double-Sided Linear Induction Motor Of Electromagnetic Catapult Of Carrier-Based Aircraft, Xijun Liu, Kunlun Zhang, Guoqing Liu

Journal of System Simulation

Abstract: To solve the low efficiency of current steam catapults of carrier-based aircraft, the authors proposed the electromagnetic catapult of carrier-based aircraft using double-sided linear induction motor. The authors analyzed the technical requirements of the catapult of carrier-based aircraft through the kinetic equations, analyzed the drive source of the catapult - long primary double-sided linear induction motor - through the physical model and equivalent circuit, derived the relationship between required thrust and the design parameters of the electromagnetic catapult, and provided specific design parameters. Using computer simulation analysis, the authors analyzed the impact of secondary length, motor pole …


All-Digital Simulation Technique With Application To On-Orbit Spacecraft Maintenance And Servicing, Gaoxiang Ouyang, Li Xin, Dong Xin, Chengmin Sun, Yang Xin Jul 2020

All-Digital Simulation Technique With Application To On-Orbit Spacecraft Maintenance And Servicing, Gaoxiang Ouyang, Li Xin, Dong Xin, Chengmin Sun, Yang Xin

Journal of System Simulation

Abstract: Aiming at the demand for the on-orbit maintenance, a new simulation technique was developed. The simulation contained on-orbit failures reproduction and location, onboard software upgrade and patch. A virtual technology was used to construct all virtual hardware environment, imitate their function and simulate the real satellite control system. This all-digital platform implemented precise multi-type faults injection, internal state monitoring and data stream intervention very well. So it could roundly simulate and test the software upgrade of the attitude and orbit control systems. It could also be used in the high-fidelity simulation of satellite-ground synchronous operation and maintenance, especially it …


Effect Of Assembly Force On Gas Diffusion Layer For Proton Exchange Membrane Fuel Cell, Yibo Zhou, Jianjian Wang Jul 2020

Effect Of Assembly Force On Gas Diffusion Layer For Proton Exchange Membrane Fuel Cell, Yibo Zhou, Jianjian Wang

Journal of System Simulation

Abstract: A three-dimensional multi-flow channel proton exchange membrane fuel cell (PEMFC) model has been developed to investigate the deformation of gas diffusion layer (GDL) with different assembly force and different contact ratio of channel. The results indicate that the GDL under the land part changes significantly while the central region under the flow channel almost has no deformation with increasing assembly force. When the contact ratio of channel is not 100%, the deformation of GDL is not symmetrical due to the shear stress, and the thickness of GDL under the flow channel even exceeds its initial thickness, which produces the …


Respond Performance To Dynamic Heat Resource Of Organic Rankine Cycle For Waste Heat Recovery On Vehicle, Zhao Li, Huang Wei Jul 2020

Respond Performance To Dynamic Heat Resource Of Organic Rankine Cycle For Waste Heat Recovery On Vehicle, Zhao Li, Huang Wei

Journal of System Simulation

Abstract: Complex traffic leads to a dynamic behavior of exhaust gas of vehicle. Therefore, a real operating of Organic Rankine Cycle (ORC), which is used for heat recovery, deviates the design working condition at most of time with a low operating efficiency. To solve the problem, a dynamic model of ORC system verified by experiment result was built. The dynamic behavior of the heat resource, divided into 6 modes, was used as an input of external condition to the developed model. The impact results of the step mass flow rate and the temperature of heat resource to the stability of …


Fault Modeling And Simulation Of Swing Infrared Earth Sensor, Jiansong Chang, Xinyan Liu Jul 2020

Fault Modeling And Simulation Of Swing Infrared Earth Sensor, Jiansong Chang, Xinyan Liu

Journal of System Simulation

Abstract: In order to meet the requirements of refined modeling and fault simulation, function modules of swing infrared earth sensor (IRES) was identified according to its working principle, main fault modes of each module was analyzed, mathematical fault model based on physical mechanism was designed, and a program for normal and fault simulation was written. The refined fault model can calculate attitude angles exactly, reflect signal relationship between inside modules, and simulate various fault modes effectively. The model can be used in simulating, testing and fault diagnosis and so on.


Computed Terahertz Wave Propagation In Marine Protective Coating, Wanli Tu, Shuncong Zhong, Zhou Qing, Ligang Yao Jul 2020

Computed Terahertz Wave Propagation In Marine Protective Coating, Wanli Tu, Shuncong Zhong, Zhou Qing, Ligang Yao

Journal of System Simulation

Abstract: The propagation of terahertz radiation in marine protective coatings was investigated based on Finite-difference time-domain method. The theoretical framework using terahertz waves for the detection of marine protective coatings was established; also, both intact and defected coating system were modelled and analyzed. The reflected radiation properties were recorded for quantitative characterisation of marine protective coating thickness. Furthermore, diagnostic analysis was done for the defects of the coating system, such as bubbling and oxidation of rust. The Finite-difference time-domain model provides some theoretical basis for nondestructive testing and evaluation of marine protective coating system by terahertz pulsed imaging technology …


Research On Effect Of Harmonic Source Equivalent Model On Harmonic Power Flow, Zhenguo Shao, Wenbo Su, Zhaoxiang Li Jul 2020

Research On Effect Of Harmonic Source Equivalent Model On Harmonic Power Flow, Zhenguo Shao, Wenbo Su, Zhaoxiang Li

Journal of System Simulation

Abstract: The models and parameters of harmonic source are the main factors that affect the calculation accuracy of harmonic flow. Harmonic source was divided into linear load and non-linear load and then modelled separately. The algorithm flowcharts, coupling method, decouple method and linear method, were analyzed with power source model, current source model and current source-impedance model correspondingly. The frequency response of those models was compared with a simple example. It indicates that the model of linear load and its affect in harmonic frequency are the key factors influencing computational accuracy of harmonic power flow. Then an example of harmonic …


Research Of 3d Cloud Illumination Model Based On Importance Sampling, Yonghua Xie, Fuxing Yuan, Wang Chang Jul 2020

Research Of 3d Cloud Illumination Model Based On Importance Sampling, Yonghua Xie, Fuxing Yuan, Wang Chang

Journal of System Simulation

Abstract: Currently existing 3D cloud simulation illumination models were confronted with the shortcomings such as complexity of implementation and low rendering efficiency. Herein a calculation method for illumination model based on importance sampling was proposed; Aiming at the problems of the old phase function, a new phase function was proposed to improve the rendering efficiency and quality. By the design of the importance function, the method did importance sampling in integrated interval and combined two phase functions to render the cloud. The results of the simulation show that the presented method has enhanced the rendering speed with the guarantee of …