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Channel Measurement and Path Loss Modeling from 220 GHz to 330 GHz for 6G Wireless Communications

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China Communications 2021年第5期18卷 19-32页

作者： pan Tang Jianhua Zhang Haoyu Tian Zhaowei Chang Jun Men yuxiang Zhang Lei Tian Liang Xia Qixing Wang Jingsuo He State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China China Mobile Research Institute Beijing 100053China Capital Normal University Beijing 100048China

Terahertz(THz)communication has been envisioned as a key enabling technology for sixthgeneration(6G).In this paper,we present an extensive THz channel measurement campaign for 6G wireless communications from 220 GHz to 330 ***,the path loss is analyzed and modeled by using two single-frequency path loss models and a multiplefrequencies path loss *** is found that at most frequency points,the measured path loss is larger than that in the free *** at around 310 GHz,the propagation attenuation is relatively weaker compared to that in the free ***,the frequency dependence of path loss is observed and the frequency exponent of the multiple-frequencies path loss model is ***,the cellular performance of THz communication systems is investigated by using the obtained path loss *** results indicate that the current inter-site distance(ISD)for the indoor scenario is too small for THz ***,the tremendous capacity gain can be obtained by using THz bands compared to using microwave bands and millimeter wave ***,this work can give an insight into the design and optimization of THz communication systems for 6G.

关键词： terahertz channel measurement channel modeling path loss

An Algorithm to Recognize the Target Object Contour Based on 2D Point Clouds by Laser-CCD-Scanning

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Wuhan University Journal of Natural Sciences 2015年第4期20卷 355-361页

作者： MAO Hongyong SHI Duanwei ZHOU Ji XU pan CHEN Shiyu XU yuxiang FENG Fan School of Power and Mechanical Engineering Wuhan University

For a vision measurement system consisted of laser-CCD scanning sensors, an algorithm is proposed to extract and recognize the target object contour. Firstly, the two-dimensional（2D） point cloud that is output by the integrated laser sensor is transformed into a binary image. Secondly, the potential target object contours are segmented and extracted based on the connected domain labeling and adaptive corner detection. Then, the target object contour is recognized by improved Hu invariant moments and BP neural network classifier. Finally, we extract the point data of the target object contour through the reverse transformation from a binary image to a 2D point cloud. The experimental results show that the average recognition rate is 98.5% and the average recognition time is 0.18 s per frame. This algorithm realizes the real-time tracking of the target object in the complex background and the condition of multi-moving objects.

关键词： laser-CCD scanning sensor 2D point cloud contour recognition improved Hu invariant moments BP neural network

Seam-tracking based on dynamic trajectory planning for a mobile welding robot

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China Welding 2019年第4期28卷 46-50页

作者： Hong yuxiang Du Dong pan Jiluan Li Xiangwen College of Mechanical and Electrical Engineering China Jiliang UniversityHangzhou 310018China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China Engineering Research Center for Complex Trajectory Machining Technology and Equipment Ministry of EducationXiangtan UniversityXiangtan 411105China

A new seam-tracking method based on dynamic trajectory planning for a mobile welding robot is proposed in order to improve the response lag of the mobile robot and the high frequency oscillation in *** using a front-placed laser-based vision sensor to dynamically extract the location of the weld seam in front of torch,the trend and direction of the weld line is roughly *** robot system autonomously and dynamically performs trajectory planning based on the isometric approximation *** sensor technology is applied to detect the offset during welding process in real *** dynamic compensation of the weld path is done in combination with the control of the mobile robot and the executive body installed on *** and experimental results demonstrate that the method effectively increases the stability of welding speed and smoothness of the weld track,and hence the weld formation in curves and corners is improved.

关键词： welding automation seam tracking mobile robot dynamic trajectory planning

基于并行融合深度残差收缩网络的有源配电网故障诊断

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综合智慧能源 2024年第6期46卷 8-15页

作者：冯骥杨国华史磊潘欢陆宇翔张元曦李祯宁夏大学电子与电气工程学院银川750021 宁夏电力能源安全重点试验室银川750004

针对含分布式电源的配电网故障呈现方式多样化以及故障诊断易受分布式电源类型、输出功率等非线性因素影响等问题,提出一种基于并行融合深度残差收缩网络(P-FDRSN)的故障诊断模型。首先,构建具有故障识别支路和故障定位支路的并行网络... 详细信息

针对含分布式电源的配电网故障呈现方式多样化以及故障诊断易受分布式电源类型、输出功率等非线性因素影响等问题,提出一种基于并行融合深度残差收缩网络(P-FDRSN)的故障诊断模型。首先,构建具有故障识别支路和故障定位支路的并行网络结构——P-FDRSN,在残差模块中引入收缩机制,减少网络中噪声或冗余信息的影响,提高网络对噪声的鲁棒性;其次,将故障录波信号波形幅值变化转换为灰度图和时频图,送入深度残差收缩网络进行深度特征提取并在汇聚层中将获取的特征进行融合,以增强故障录波信号的特征学习能力。仿真结果表明:在不同分布式电源类型和不同输出功率下,模型故障定位与识别精度均能保持在98.75%和97.25%以上,即使在噪声干扰的情况下,诊断准确率仍可保持在96.75%以上,模型具有较高的精度和较好的自适应性。

关键词：有源配电网分布式电源故障诊断并行网络结构并行融合深度残差收缩网络

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人犬互动对犬刻板行为、皮质醇浓度的影响

家畜生态学报 2024年第6期45卷 43-49页

作者：孙宁赵禹徐澍朱启文付家琳俞曦修福晓杨宇翔潘彩霞水映懿黄和中国刑事警察学院辽宁沈阳110034 辽宁省行为认知重点实验室沈阳医学院辽宁沈阳110034 安徽省铜陵市公安局安徽铜陵244000 中国人民公安大学北京100038

犬在犬舍中刻板行为高发,为有效降低犬舍空间和条件不佳等应激因素,改善犬福利状态,本研究通过实施人犬互动,探讨其对刻板行为及皮质醇浓度的影响。人犬互动程序是训导员牵引犬到300 m2室外草坪区进行游戏,包括使用麻棒、网球等玩具及... 详细信息

犬在犬舍中刻板行为高发,为有效降低犬舍空间和条件不佳等应激因素,改善犬福利状态,本研究通过实施人犬互动,探讨其对刻板行为及皮质醇浓度的影响。人犬互动程序是训导员牵引犬到300 m2室外草坪区进行游戏,包括使用麻棒、网球等玩具及抚拍等方式,每次人犬互动时间为60 min,在互动过程中的第0、15、30、45、60、75、90 min采集唾液样本,用于检测唾液皮质醇;人犬互动试验持续20 d,在人犬互动前、后评估人犬互动对犬刻板行为的影响,并采集粪便样本,用于检测粪便皮质醇水平的变化。结果表明,犬的刻板行为表现为踱步、盘旋、犬舍转圈行走、墙反弹、食粪等。经过人犬互动后,犬的刻板行为明显降低(P<0.01),由32.7%±8.32%降至18.3%±2.27%;在3个工作犬品种中,人犬互动对马里努阿犬的影响最大。经过20 d的人犬互动,粪便皮质醇水平显著降低(P<0.01),互动前粪便皮质醇浓度457.0±17.80 pg/mg,互动后粪便皮质醇浓度241.8±17.71 pg/mg。犬的刻板行为与粪便皮质醇水平之间无相关性。在互动过程中,唾液皮质醇浓度显著且持续下降,由基础值4.0±0.30 nmol/L下降至2.4±0.28 nmol/L,互动结束30 min后,皮质醇浓度趋于恢复到基础水平,但低于基础水平。试验表明,定期进行每日30 min的人犬互动可以有效减轻犬刻板行为等应激反应。

关键词：人犬互动刻板行为唾液皮质醇粪便皮质醇

Is there a survival benefit from adjuvant chemotherapy for patients with liver oligometastases from colorectal cancer after curative resection?

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Cancer Communications 2018年第1期38卷 319-328页

作者： Zhizhong pan Jianhong Peng Junzhong Lin Gong Chen Xiaojun Wu Zhenhai Lu yuxiang Deng Yujie Zhao Qiaoqi Sui Desen Wan Department of Colorectal Surgery Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer Medicine651 Dongfeng Road EastGuangzhou 510060GuangdongP.R.China

Background:Although colorectal oligometastases to the liver can potentially be cured with aggressive local abla-tion,the efficacy of adjuvant chemotherapy(ACT)for such metastasis remains *** present study explored the effects of ACT on patients with colorectal liver oligometastases(CLO)after curative resections and aimed to iden-tify patients who could benefit from ***:We retrospectively analyzed 264 eligible patients with CLO who underwent curative resection between September 1999 and June ***-free survival(RFS)and overall survival(OS)were analyzed using the Kaplan-Meier method and log-rank test;prognostic factors were a by Cox regression ***:Among 264 patients,200(75.8%)patients received ACT and 64(24.2%)did not receive *** two groups did not significantly differ in clinicopathologic characteristics,and had comparable 3-year OS and RFS rates(RFS:42.1%vs.45.7%,P=0.588;OS:69.7%vs.62.7%,P=0.446)over a median follow-up duration of 35.5 months,irrespective of preoperative *** markedly improved 3-year OS in high-risk patients with Memorial Sloan-Kettering Cancer Center clinical risk scores(MSKCC-CRS)of 3-5(68.2%vs.33.8%,P=0.015),but presented no additional benefit in patients with MSKCC-CRS of 0-2(72.2%vs.78.6%,P=0.834).In multivariate analysis,ACT was independently associated with improved OS in patients with MSKCC-CRS of ***:ACT might offer a prognostic benefit in high-risk patients with CLOs after curative liver resection,but not in low-risk ***,patients’risk status should be determined before ACT administration to optimize postoperative therapeutic strategies.

关键词： Colorectal cancer Oligometastases Adjuvant chemotherapy Liver resection Benefit

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脑室及脑实质内神经鞘瘤临床特点分析

国际神经病学神经外科学杂志 2024年第3期51卷 45-54页

作者：蒋念潘舟洋陈银华廖宇翔廖新斌张治平中南大学湘雅医院神经外科湖南长沙410008

目的总结脑室及脑实质内神经鞘瘤的临床特点。方法收集2010年6月—2020年6月中南大学湘雅医院诊治的13例脑室及脑实质内神经鞘瘤病例,并分析患者的一般资料、症状、体征、影像学资料、手术记录以及住院治疗经过。结果13例非颅神经起源... 详细信息

目的总结脑室及脑实质内神经鞘瘤的临床特点。方法收集2010年6月—2020年6月中南大学湘雅医院诊治的13例脑室及脑实质内神经鞘瘤病例,并分析患者的一般资料、症状、体征、影像学资料、手术记录以及住院治疗经过。结果13例非颅神经起源的脑实质内或脑室神经鞘瘤,占同期神经鞘瘤的0.45%。患者年龄1~71岁,平均35.7岁;男性9例,女性4例(男∶女=2.25∶1.00)。患者症状出现时间从4 d到3年不等,最常见的首发症状是头痛,其次是癫痫发作。肿瘤位于额叶最常见,其次为小脑半球和颞叶。囊变、瘤周水肿是该肿瘤常见影像学特征,1例病例出现钙化。该13例术前均误诊为其他类型肿瘤,多数诊断为胶质瘤或脑膜瘤。结论脑室及脑实质内神经鞘瘤是一种罕见的肿瘤,术前难以与实质性肿瘤鉴别。该肿瘤起因不明,手术为首选治疗方式,除恶性神经鞘瘤外预后均较好。

关键词：神经鞘瘤脑实质脑室临床特点神经影像组织病理

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天然高分子材料对卷烟包灰性能的影响

纤维素科学与技术 2024年第1期32卷 66-72,I0002页

作者：许春平吴攀刘远上苏海洋薛芳贾学伟代玉祥施丰成郑州轻工业大学烟草科学与工程学院河南郑州450000 河北中烟工业有限责任公司河北石家庄050000 四川中烟工业有限责任公司卷烟减害降焦四川省重点实验室四川成都610000

为考察天然高分子材料的种类及添加量对卷烟包灰性能的影响,利用图像分析法测定添加天然高分子材料后卷烟的包灰值、灰度值、碳化圈宽度、锥高和锥顶角,采用单因素方差分析、简单相关分析研究天然高分子材料与卷烟包灰性能之间的相关性... 详细信息

为考察天然高分子材料的种类及添加量对卷烟包灰性能的影响,利用图像分析法测定添加天然高分子材料后卷烟的包灰值、灰度值、碳化圈宽度、锥高和锥顶角,采用单因素方差分析、简单相关分析研究天然高分子材料与卷烟包灰性能之间的相关性,结合层次分析法对添加天然高分子材料的卷烟综合包灰性能进行评价。结果表明:1)与对照组相比,添加1.0%纤维素纳米纤维(CNFs)15μL的卷烟包灰值、灰度值最小,燃烧后卷烟灰柱裂口最少,颜色最白;添加1.5%改性纤维素纳米纤维(MCNFs)15μL的卷烟碳化圈宽度最窄。2)CNFs的浓度与包灰值和碳化圈宽度都呈显著负相关,山药多糖浓度与包灰值呈极显著负相关;罗汉果多糖浓度与包灰值、灰度值呈显著负相关。且卷烟包灰性能的好坏是各个包灰指标综合的表现。3)对包灰指标进行梯度划分,结合层次分析法得到卷烟包灰指标综合性能得分,由结果可知,添加1.0%CNFs15μL的卷烟包灰综合性能得分较空白对照组明显升高,包灰性能最好。

关键词：天然高分子材料卷烟纸包灰性能相关性分析

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重型全时全驱分动器电控系统设计

汽车电器 2024年第6期 65-68页

作者：周元豪魏志强赵天玉张霞霞荆攀刘宇翔陕西重型汽车有限公司陕西西安710200

文章首先分析传统机械重型全时全驱分动器在使用及维护中的缺点,结合实际使用需求,在原有重型全时全驱分动器上加装电子控制系统之后,在满足基础功能的同时也可实时反馈运行状态,具备安全冗余措施及故障诊断机制。实践证明:该系统结构... 详细信息

文章首先分析传统机械重型全时全驱分动器在使用及维护中的缺点,结合实际使用需求,在原有重型全时全驱分动器上加装电子控制系统之后,在满足基础功能的同时也可实时反馈运行状态,具备安全冗余措施及故障诊断机制。实践证明:该系统结构简单、操作便捷,方便故障维修,在操作与使用过程中,能够有效防止误操作,提高分动器使用效率,减小分动器损坏风险,并且控制器能够与车辆其它电控系统通过CAN总线互通互联,有利于提高车辆整体电控化程度。

关键词：分动器电子控制 CAN总线