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基于全局导向的智能车辆路径规划融合算法研究

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汽车工程 2024年第9期46卷 1546-1555页

作者：张硕邝士奇赵轩陈轶嵩余强余曼长安大学汽车学院长安大学工程机械学院

针对曲线道路的路径规划问题，本文提出一种基于全局导向人工势场法的路径规划融合算法。考虑持续转弯的弯曲道路工况，构建基于变形栅格的栅格地图；考虑道路环境中的行车风险，基于行车风险场理论优化A*算法启发函数从而改进A*算法。... 详细信息

针对曲线道路的路径规划问题，本文提出一种基于全局导向人工势场法的路径规划融合算法。考虑持续转弯的弯曲道路工况，构建基于变形栅格的栅格地图；考虑道路环境中的行车风险，基于行车风险场理论优化A*算法启发函数从而改进A*算法。改进传统人工势场法的局限性及固有缺陷，在局部路径规划中考虑自车、环境车辆及障碍物的轮廓形状，引入全局导向路径进一步改进人工势场法。以改进A*算法规划路径为全局最优导向路径，设计基于改进人工势场法的路径规划融合算法。仿真结果表明，提出的融合算法可以生成有效的行驶路径，与数据集提取的实车路径接近，且在障碍物环境中规划的路径安全高效，满足车辆的行驶要求。

关键词：路径规划栅格地图 A~*算法人工势场法

基于Stanley单点预瞄的LKA融合控制算法研究

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汽车实用技术 2024年第9期49卷 43-49页

作者：邝士奇长安大学汽车学院陕西西安710064

为解决在弯道干扰下车道保持辅助(LKA)系统跟踪精度低、行驶稳定性差的问题,文章针对装备LKA系统的车辆进行操纵稳定性方面的研究。建立了基于单点预瞄最优曲率模型和Stanley算法预瞄模型的目标转角模块,并通过控制转角权重模型允许对... 详细信息

为解决在弯道干扰下车道保持辅助(LKA)系统跟踪精度低、行驶稳定性差的问题,文章针对装备LKA系统的车辆进行操纵稳定性方面的研究。建立了基于单点预瞄最优曲率模型和Stanley算法预瞄模型的目标转角模块,并通过控制转角权重模型允许对各个预瞄模型计算出的转角进行加权组合。通过其余控制模块的协同工作,确保了目标转角模块可以提供准确且适宜的转角指导,帮助车辆保持在车道中心,应对各种驾驶路况,实现最佳的转向响应。文章通过MATLAB/Simulink和TruckSim搭建了LKA系统的车辆仿真平台,通过设置不同的驾驶工况,研究不同车速、不同道路线型对轨迹跟踪性能的影响。联合仿真验证了算法有效性,结果显示,所设计的LKA融合控制算法模型在弯道干扰下表现出强鲁棒性、高跟踪精度和稳定性,在多种转向场景中保持了良好的性能和约束满足,确保了行车精确性和稳定性。

关键词：车道保持辅助系统联合仿真单点预瞄 Stanley算法 MATLAB/Simulink TruckSim

百日咳患儿血清IFN-γ、IL-5水平及其与免疫状态的关系

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检验医学与临床 2024年第15期21卷 2243-2247页

作者：李小梅匡诗琪曾美玲唐绘卓贺安湖南省郴州市第一人民医院儿童感染科湖南郴州423000 湖南省郴州市第一人民医院检验科湖南郴州423000

目的探讨百日咳患儿血清γ-干扰素(IFN-γ)、白细胞介素-5(IL-5)水平及其与免疫状态的关系。方法选取2021年1月至2023年12月该院儿科收治的300例百日咳患儿临床资料进行回顾性分析,根据患儿不同免疫状态分为未免疫组、部分免疫组和完全... 详细信息

目的探讨百日咳患儿血清γ-干扰素(IFN-γ)、白细胞介素-5(IL-5)水平及其与免疫状态的关系。方法选取2021年1月至2023年12月该院儿科收治的300例百日咳患儿临床资料进行回顾性分析,根据患儿不同免疫状态分为未免疫组、部分免疫组和完全免疫组。比较3组患儿入院时血清IFN-γ、IL-5水平,并根据患儿年龄及完全免疫患儿接种时长进行分组,观察不同分组状况下患儿血清IFN-γ、IL-5水平。采用多因素Logistic回归分析百日咳患儿血清IFN-γ、IL-5水平及其与免疫状态的关系。结果完全免疫组患儿血清IFN-γ水平高于未免疫组和部分免疫组,血清IL-5水平低于未免疫组和部分免疫组,差异均有统计学意义(P3~6岁患儿血清IFN-γ水平高于其他年龄段患儿,IL-5水平低于其他年龄段患儿,差异均有统计学意义(P0.05)。结论不同免疫状态的百日咳患儿血清IFN-γ、IL-5水平存在一定差异,二者水平在一定程度上与患儿的免疫状态有关。

关键词：百日咳免疫状态 γ-干扰素白细胞介素-5 痉挛样咳嗽期

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小鼠脑海绵状血管瘤模型

国际脑血管病杂志 2023年第11期31卷 868-874页

作者：旷诗琪林晶陈琳南华大学附属第二医院神经内科衡阳421000 南昌大学附属第一医院神经内科南昌330000

脑海绵状血管瘤(cerebral cavernous malformation,CCM)是一种常见的脑血管畸形,发病率为0.16%~0.5%。CCM可以散发性和家族性形式存在,后者以常染色体显性方式遗传,其发病与CCM1、CCM2和CCM3基因突变有关,这些基因的体细胞突变是发生脑... 详细信息

脑海绵状血管瘤(cerebral cavernous malformation,CCM)是一种常见的脑血管畸形,发病率为0.16%~0.5%。CCM可以散发性和家族性形式存在,后者以常染色体显性方式遗传,其发病与CCM1、CCM2和CCM3基因突变有关,这些基因的体细胞突变是发生脑部病变的基础。为了探索CCM的发病机制以及寻找治疗靶点,已构建多种CCM动物模型,为CCM的病理生理学机制研究提供了帮助。然而,每种CCM模型均有各自的优缺点和适用性。小鼠是最常用于构建CCM模型的动物。因此,文章归纳了目前小鼠CCM模型的特点及其研究进展。

关键词：血管瘤,海绵状,中枢神经系统疾病模型,动物小鼠小鼠,基因敲除

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基于CFAR-CNN的轻量级海上目标检测

雷达科学与技术 2024年第3期22卷 312-320页

作者：刘世琦匡华星杨昊成中国船舶集团有限公司第七二四研究所江苏南京211153 东南大学江苏南京210096

针对海防雷达分辨率低、实时性要求高及传统CFAR算法难以满足日益精细的现代化战争需求的问题。本文将传统的CA-CFAR算法融入到计算机视觉的两阶段目标检测框架中,形成了一种轻量、高效的雷达实时目标检测算法。首先使用低门限CFAR(Lo-C... 详细信息

针对海防雷达分辨率低、实时性要求高及传统CFAR算法难以满足日益精细的现代化战争需求的问题。本文将传统的CA-CFAR算法融入到计算机视觉的两阶段目标检测框架中,形成了一种轻量、高效的雷达实时目标检测算法。首先使用低门限CFAR(Lo-CFAR)来判断诸多潜在目标的真实位置或虚警位置。然后,根据点迹位置信息和雷达回波距离-方位图做数据切片。最后,采用高性能分类器对数据切片进行训练。实测数值实验表明:与传统CFAR,Faster R-CNN算法相比,所提方法在提高检测概率、抑制虚警和轻量时效性方面有显著优势。

关键词：雷达目标检测二阶段轻量化神经网络数据切片

The influence of urban three-dimensional structure and building greenhouse effect on local radiation flux

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Science China Earth Sciences 2021年第11期64卷 1934-1948页

作者： Renhua ZHANG Wenhui kuang shiqi YANG Zhaoliang LI Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China

Accurate measurements of the three-dimensional structure characteristics of urban buildings and their greenhouse effect are important for evaluating the impact of urbanization on the radiation energy budget and research on the urban heat island(UHI)*** decrease in evapotranspiration or the increase in sensible heat caused by urbanization is considered to be the main cause of the UHI effect,but little is known about the influence of the main factor“net radiant flux”of the urban surface heat *** this study,experimental observation and quantitative model simulation were used to find that with the increase of building surface area after urbanization,the direct solar radiation flux and net radiation flux on building surface areas changed *** order to accurately quantify the relationship between the positive and negative effects,this study puts forward the equivalent calculation principle of“aggregation element”,which is composed of a building’s sunny face and its shadow face,and the algorithm of the contribution of the area to thermal *** research clarifies the greenhouse effect of a building with walls of glass *** shows that when the difference between absorption rates of a concrete wall and grass is−0.21,the cooling effect is *** the case of concrete walls with glass windows,the difference between absorption rates of a building wall and grass is−0.11,which is also a cooling *** greenhouse effect value of a building with glass windows reduces the cooling effect value to 56%of the effect of a building with concrete *** simulation of changes in net radiant flux and flux density shows that the greenhouse effect of a 5-story building with windows yields 15.5%less cooling effect than one with concrete walls,and a 30-story building with windows reduces the cooling effect by 23.0%.The simulation results confirmed that the difference in the equivalent absorption rate of the aggregation element is the“director”of

关键词： Aggregation element algorithm Greenhouse effect of buildings with windows Net radiation flux Direct solar radiation flux Architectural shadow

Cooperative beamforming design for physical-layer security of multi-hop MIMO communications

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Science China(Information Sciences) 2016年第6期59卷 153-166页

作者： shiqi GONG Chengwen XING Zesong FEI Jingming kuang School of Information and Electronics Beijing Institute of Technology

The security issue is critically important for wireless communications, especially for multi-hop communications. In this paper, we propose a cooperative secrecy beamforming scheme for a multi-hop MIMO communication network, in which there is a single-antenna source, multiple multi-antenna relays and a singleantenna destination. Moreover, two types of eavesdroppers exist in the network, one of which has known channel state information(CSI), while the other not. To achieve security communications, in our work null-space beamforming and artificial noise beamforming are jointly optimized to improve the secrecy rate of the multi-hop network. In nature, the joint optimization is nonconvex and challenging. Exploiting its structure, the considered optimization problem is decoupled into a series of subproblems that can be efficiently solved based on convex optimization theory. Finally, some numerical experiment results are provided to assess the performance of the proposed secrecy beamforming design.

关键词： MIMO physical layer security multi-hop network null-space beamforming artificial noise

A QoE-based jointly subcarrier and power allocation for multiuser multiservice networks

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Science China Earth Sciences 2016年第12期59卷 34-46页

作者： Niwei WANG shiqi GONG Zesong FEI Jingming kuang School of Information and Electronics Beijing Institute of Technology

Quality of experience(QoE) is widely applied to reflect user's satisfaction of the network service,which exactly conforms to the user-centric concept in 5G. In this paper, we propose a QoE-based subcarrier and power allocation algorithm for the downlink transmission of a multiuser multiservice system. For the subcarrier allocation algorithm, the rate proportional fairness factor is defined to ensure the fairness between users. Based on different QoE models of three services, i.e., file down(FD), video streaming and voice over internet protocol(VOIP), a multi-objective optimization method is exploited to allocate the power resource by minimizing the total power consumption and maximizing the mean opinion score(MOS) value of users simultaneously. Simulation results indicate that the proposed algorithm has less power consumption and higher QoE performance than the traditional proportional fairness(PF) algorithm. In addition, the proposed algorithm can achieve nearly the same fairness performance as the PF algorithm. Moreover, when the number of subcarriers becomes larger, the power assumption will be less but with little influence on both the QoE and fairness performances.

关键词： QoE QoS MOS multiservice multi-objective optimization

Resource Allocation for Physical Layer Security in Heterogeneous Network with Hidden Eavesdropper

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China Communications 2016年第3期13卷 82-95页

作者： GONG shiqi XING Chengwen FEI Zesong kuang Jingming School of Information and Electronics Beijing Institute of Technology

The tremendous performance gain of heterogeneous networks(Het Nets) is at the cost of complicated resource allocation. Considering information security, the resource allocation for Het Nets becomes much more challenging and this is the focus of this paper. In this paper, the eavesdropper is hidden from the macro base stations. To relax the unpractical assumption on the channel state information on eavesdropper, a localization based algorithm is first given. Then a joint resource allocation algorithm is proposed in our work, which simultaneously considers physical layer security, cross-tier interference and joint optimization of power and subcarriers under fairness requirements. It is revealed in our work that the considered optimization problem can be efficiently solved relying on convex optimization theory and the Lagrangian dual decomposition method is exploited to solve the considered problem effectively. Moreover, in each iteration the closed-form optimal resource allocation solutions can be obtained based on the Karush-Kuhn-Tucker(KKT) conditions. Finally, the simulation results are given to show the performance advantages of the proposed algorithm.

关键词： resource allocation physical layer security heterogeneous networks RSS-based location estimation lagrangian dual decomposition