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Path Planning Approach in Unknown Environment

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International Journal of Automation and computing 2010年第3期7卷 310-316页

作者： Ting-Kai Wang Quan dang pei-Yuan Pan Faculty of Computing London Metropolitan University London N7 8DB UK

This paper presents a new algorithm of path planning for mobile robots, which utilises the characteristics of the obstacle border and fuzzy logical reasoning. The environment topology or working space is described by the time-variable grid method that can be further described by the moving obstacles and the variation of path safety. Based on the algorithm, a new path planning approach for mobile robots in an unknown environment has been developed. The path planning approach can let a mobile robot find a safe path from the current position to the goal based on a sensor system. The two types of machine learning： advancing learning and exploitation learning or trial learning are explored, and both are applied to the learning of mobile robot path planning algorithm. Comparison with A＊ path planning approach and various simulation results are given to demonstrate the efficiency of the algorithm. This path planning approach can also be applied to computer games.

关键词： Path planning fuzzy reasoning unknown environment mobile robot learning algorithm.

ROl-constrained visualization of flood scenes to improve perception efficiency

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International Journal of Digital Earth 2023年第1期16卷 3065-3084页

作者： Jigang You Jun Zhu Weilian Li Yukun Guo Lin Fu pei dang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China

Efficient and intuitive representation of floods can improve people's perception,which is useful for flood emergency management_and decision ***,the current methods of visualizing flood disaster scenes have the shortcomings of data redundancy and *** interference of the complex background can be avoided through region of interest(ROl)extraction,because the attention will be quickly attracted by a few salient visual ***,the characteristics of the flood disaster scene object are analysed,and the method for scene division and data organization is ***,the region of interest is extracted according to the time series data of the flood evolution process simulated using cellular automata,and the dynamic identification model of the objects of interest is ***,a dynamic scheduling queue model with service interruption is designed to optimize the rendering efficiency of flood scenes and improve the perception ***,a prototype visualization system was developed and the experimental results show that approximately 30%of the redundant data are reduced,and the scene rendering efficiency is increased by approximately 15%.The non-ROl visualization is weakened by using the rules of human visual cognition,which improves the perception efficiency of flood scenes.

关键词： Floods region of interest perception effciency 3D scenes adaptive optimization

Guided-YNet: Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network

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Computers, Materials & Continua 2024年第9期80卷 4813-4832页

作者： Tao Zhou Yunfeng Pan Huiling Lu pei dang Yujie Guo Yaxing Wang School of Computer Science and Engineering North Minzu UniversityYinchuan750021China School of Medical Information&Engineering Ningxia Medical UniversityYinchuan750004China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission NorthMinzuUniversityYinchuan750021China

Multimodal lung tumor medical images can provide anatomical and functional information for the same *** as Positron Emission Computed Tomography(PET),Computed Tomography(CT),and *** to utilize the lesion anatomical and functional information effectively and improve the network segmentation performance are key *** solve the problem,the Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network(Guide-YNet)is proposed in this ***,a double-encoder single-decoder U-Net is used as the backbone in this model,a single-coder single-decoder U-Net is used to generate the saliency guided feature using PET image and transmit it into the skip connection of the backbone,and the high sensitivity of PET images to tumors is used to guide the network to accurately locate ***,a Cross Scale Feature Enhancement Module(CSFEM)is designed to extract multi-scale fusion features after ***,a Cross-Layer Interactive Feature Enhancement Module(CIFEM)is designed in the encoder to enhance the spatial position information and semantic ***,a Cross-Dimension Cross-Layer Feature Enhancement Module(CCFEM)is proposed in the decoder,which effectively extractsmultimodal image features through global attention and multi-dimension local *** proposed method is verified on the lung multimodal medical image datasets,and the results showthat theMean Intersection overUnion(MIoU),Accuracy(Acc),Dice Similarity Coefficient(Dice),Volumetric overlap error(Voe),Relative volume difference(Rvd)of the proposed method on lung lesion segmentation are 87.27%,93.08%,97.77%,95.92%,89.28%,and 88.68%,*** is of great significance for computer-aided diagnosis.

关键词： Medical image segmentation U-Net saliency feature guidance cross-modal feature enhancement cross-dimension feature enhancement

Enhancement of radiosensitization by metal-based nanoparticles in cancer radiation therapy

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Cancer Biology & Medicine 2014年第2期11卷 86-91页

作者： Xiang-Yu Su pei-dang Liu Hao Wu Ning Gu Department of Oncology Zhongda Hospital of Southeast University Jiangsu Key Laboratory for Biomaterials and Devices Southeast University

Radiation therapy performs an important function in cancer treatment. However, resistance of tumor cells to radiation therapy still remains a serious concern, so the study of radiosensitizers has emerged as a persistent hotspot in radiation oncology. Along with the rapid advancement of nanotechnology in recent years, the potential value of nanoparticles as novel radiosensitizers has been discovered. This review summarizes the latest experimental findings both in vitro and in vivo and attempts to highlight the underlying mechanisms of response in nanoparticle radiosensitization.

关键词： Nanoparticles radiation tolerance cancer radiotherapy

A real 3D scene rendering optimization method based on region of interest and viewing frustum prediction in virtual reality

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International Journal of Digital Earth 2022年第1期15卷 1081-1100页

作者： pei dang Jun Zhu Jianlin Wu Weilian Li Jigang You Lin Fu Yiqun Shi Yuhang Gong Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany Faculty of Civil Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Department of Natural Resources of Sichuan Province Sichuan Institute of Land Science and TechnologyChengduPeople’s Republic of China

As an important technology of digital construction,real 3D models can improve the immersion and realism of virtual reality(VR)*** large amount of data for real 3D scenes requires more effective rendering methods,but the current rendering optimization methods have some defects and cannot render real 3D scenes in virtual *** this study,the location of the viewing frustum is predicted by a Kalman filter,and eye-tracking equipment is used to recognize the region of interest(ROI)in the ***,the real 3D model of interest in the predicted frustum is rendered *** experimental results show that the method of this study can predict the frustrum location approximately 200 ms in advance,the prediction accuracy is approximately 87%,the scene rendering efficiency is improved by 8.3%,and the motion sickness is reduced by approximately 54.5%.These studies help promote the use of real 3D models in virtual reality and ROI recognition *** future work,we will further improve the prediction accuracy of viewing frustums in virtual reality and the application of eye tracking in virtual geographic scenes.

关键词： Real 3D scene virtual reality Kalman filter region of interest viewing frustum

An improved social force model (ISFM)-based crowd evacuation simulation method in virtual reality with a subway fire as a case study

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International Journal of Digital Earth 2023年第1期16卷 1186-1204页

作者： Jinbin Zhang Jun Zhu pei dang Jianlin Wu Yuxuan Zhou Weilian Li Lin Fu Yukun Guo Jigang You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany School of Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China

Crowd evacuation simulation using virtual reality(VR)is significant for digital emergency response ***,existing evacuation simulation studies suffer from poor adaptation to complex environments,inefficient evacuations,and poor simulation effects and do not fully consider the impacts of specific disaster environments on crowd *** more realistically express the crowd evacuation results obtained under the influence offire environments and the subjective consciousness of pedestrians in subway stations,we designed a dynamic pedestrian evacuation path planning method under multiple constraints,analysed the influences of an‘environmental role’and a‘subjective initiative’on crowd evacuation,established an improved social force model(ISFM)-based crowd evacuation simulation method in VR,developed a prototype system and conducted experimental *** experimental results show that the crowd evacuation time of the ISFM is affected by the disaster *** simulation experiments without disaster scenarios,the improved model’s crowd evacuation efficiency improved by averages of 12.53%and 15.37%over the commercial Pathfinder software and the original social force model,*** method described herein can effectively support real-time VR crowd evacuation simulation under multiexit and multifloor conditions and can provide technical support for emergency evacuation learning and management decision analyses involving subwayfires.

关键词： Subway stationfire improved social force model crowd evacuation simulation virtual reality path planning

Tunnel vision optimization method for VR flood scenes based on Gaussian blur

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International Journal of Digital Earth 2021年第7期14卷 821-835页

作者： Lin Fu Jun Zhu Weilian Li Qing Zhu Bingli Xu Yakun Xie Yunhao Zhang Ya Hu Jingtao Lu pei dang Jigang You Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Department of Information and Communication The Army Academy of Armored ForcesBejingPeople’s Republic of China

The visualization of flood disasters in virtual reality(VR)scenes is useful for the representation and sharing of disaster knowledge and can effectively improve users’cognitive efficiency in comprehending disaster ***,the existing VR methods of visualizing flood disaster scenes have some shortcomings,such as low rendering efficiency and poor user *** this paper,a tunnel vision optimization method for VR flood scenes based on Gaussian blur is *** key techniques are studied,such as region of interest(ROI)calculation and tunnel vision optimization considering the characteristics of the human visual system.A prototype system has been developed and used to carry out an experimental case *** experimental results show that the number of triangles drawn in a flood VR scene is reduced by approximately 30%–40%using this method and that the average frame rate is stable at approximately 90 frames per second(fps),significantly improving the efficiency of scene rendering and reducing motion sickness.

关键词： Flood disaster virtual reality Gaussian blur tunnel vision scene optimization

A dynamic holographic modelling method of digital twin scenes for bridge construction

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International Journal of Digital Earth 2023年第1期16卷 2404-2425页

作者： Jianlin Wu Jun Zhu Jinbin Zhang pei dang Weilian Li Yukun Guo Lin Fu Jianbo Lai Jigang You YaKun Xie Ce Liang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople’s Republic of China Institute of Geodesy and Geoinformation University of BonnBonnGermany School of Engineering and Geomatics Southwest Petroleum UniversityChengduPeople’s Republic of China Institute of Computing Technology China Academy of Railway Sciences CoLtdBeijingPeople’s Republic of China

Holographic projection technology can provide a more intuitive and efficient visualization effect for a digital twin bridge construction ***,pre-rendering methods in the existing research work are usually used to implement holographic visualization,which is static *** above-mentioned methods for static display have many shortcomings,such as poor adaptability,low rendering efficiency and lack of real-time.A dynamic holographic modelling approach is proposed for the augmented visualization of digital twin scenes for bridge ***,a dynamic segmentation algorithm with adaptive screen size was designed to high-efficiently generate holographic ***,a motion blur control method was designed to improve the rendering efficiency of holographic scenes according to human visual ***,a prototype system was developed,and the corresponding experimental analysis was *** experimental results show that the method proposed in this article can support adaptive screen size image segmentation and real-time generation of holographic scenes for bridge *** amount of scene data can be reduced to more than 30%,which significantly improves rendering efficiency and reduces glare.

关键词： Bridge construction Digital twins Holographic scene Adaptive segmentation Rendering optimization

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基于情感基音模板的情感语音合成

中南大学学报（自然科学版） 2010年第6期41卷 2258-2263页

作者：陈明义党培霞中南大学信息科学与工程学院湖南长沙410083

为了合成能够模拟表达说话人的情感状态的语音,提出一种基于情感基音模板的情感语音合成方法。该方法分别建立高兴、愤怒、悲伤和中立4种不同情感下的韵母基音模板库,建立4种声调模型,统计分析语音库中情感语音的韵律特征参数,运用基音... 详细信息

为了合成能够模拟表达说话人的情感状态的语音,提出一种基于情感基音模板的情感语音合成方法。该方法分别建立高兴、愤怒、悲伤和中立4种不同情感下的韵母基音模板库,建立4种声调模型,统计分析语音库中情感语音的韵律特征参数,运用基音同步叠加算法(PSOLA)合成含情感色彩的语音。实验以音节为合成单位,根据情感特征参数的统计分析结果调节合成语音的韵律特征,合成各种情感的语音。仿真实验结果表明:用情感基音模板合成的目标情感语音具有目标情感的音质色彩,再通过韵律参数调节,可合成较理想的情感语音。该方法可用于增加语音合成系统的智能化,提高人机交互的能力。

关键词：情感语音合成情感基音模板基音同步叠加算法韵律参数