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基于改进TDOA与卡尔曼预测模型的目标定位跟踪算法研究

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现代雷达 2024年第7期46卷 62-70页

作者：李茂幸小又钟志文刘司洋宁召柯李雪婷四川大学空天科学与工程学院四川成都610065 机器人卫星四川省重点实验室四川成都610065

针对无人机集群无源定位领域的目标跟踪问题,提出了一种基于改进到达时间差(TDOA)算法与卡尔曼预测模型的目标定位跟踪算法。首先,针对现有基于Chan的TDOA算法在时差值精度不够时定位精度差,以及现有基于Taylor的TDOA算法受迭代初始值... 详细信息

针对无人机集群无源定位领域的目标跟踪问题,提出了一种基于改进到达时间差(TDOA)算法与卡尔曼预测模型的目标定位跟踪算法。首先,针对现有基于Chan的TDOA算法在时差值精度不够时定位精度差,以及现有基于Taylor的TDOA算法受迭代初始值影响大导致算法稳健性不足的问题,提出基于Chan-Taylor的改进TDOA算法,该算法通过Chan算法快速求解出目标位置初始估计值,然后使用Taylor算法迭代求解出目标位置,在提高定位效率、缩短定位时间的基础上,提高了定位精度。其次,利用卡尔曼预测模型,将目标运动模型产生的目标位置预测值作为先验信息带入目标定位算法,通过将预测信息与定位信息有效融合,进一步提高目标定位精度。最后,通过实验仿真,从累积分布函数(CDF)、定位精度几何因子(GDOP),以及定位跟踪RMSE多个方面验证文中所提算法的正确性及有效性。

关键词：无人机集群目标定位跟踪到达时间差 Chan-Taylor改进算法卡尔曼预测模型

Ablation Mechanism of Carbon/Carbon Composites Modified by HfC–SiC in Two Conditions Under Oxyacetylene Torch

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Journal of Materials Science & Technology 2017年第1期33卷 71-78页

作者： Ke-Zhi Li Tao Duan Jia-Ping Zhang ning-Kun Liu mao-Yan Zhang State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research Center Northwestern Polytechnical University Xi'an 710072 China

C/C-HfC-SiC composites prepared by precursor infiltration and pyrolysis process were ablated by oxyacetylene torch under two different flame conditions. The ablation performance of the composites was investigated in the heat flux of 2.38 MW/m2 （HF-L） and 4.18 MW/m2 （HF-H） for 60 s. The mechanical denudation in 4.18 MW/m2 （HF-H） was higher than that in 2.38 MW/m2 （HF-L）, while the results indicated that the composites had a similar and good ablation property under two different flame conditions. C/C- HfC-SiC composites can adapt the heat flux from 2.38 MW/m2 to 4.18 MW/m2. The Hf02 was not melted completely in the heat flux of 2.38 MW/m2 （HF-L）. So, both Hf02 and Si02 layers acted as an effective barrier to the transfer of heat and oxidative gases into the underlying carbon substrate. SiO2 was severely consumed in 4.18 MW/m2 （HF-H）, where the HfO2 molten layer played a more important role in protecting the inner composite.

关键词： Carbon/carbon composites Corrosion Ablation performance

Recent developments in homobimetallic reagents and catalysts for organic synthesis

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Chinese Science Bulletin 2011年第17期56卷 1753-1769页

作者： WU Wei GU DeLiang WANG ShiMeng ning YingNan mao GuoLiang Provincial Key Laboratory of Oil and Gas Chemical Technology College of Chemistry and Chemical Engineering Northeast Petroleum University Daqing 163318 China

Organometallics are a family of useful organic chemicals because they play important roles in organic synthesis as reagents and as *** can be classified according to the number of metals they *** compounds are important organometallics and they are either homobimetallic or heterobimetallic depending on whether the two metals are the same or *** this paper,we focus on homobimetallic *** compounds are generally used as dianions to react with electrophiles in organic ***,homobimetallics have also been used as catalysts in organic reactions such as in asymmetric reactions.

关键词：有机合成试剂催化剂有机金属化合物有机化工原料双金属化合物有机反应不对称反应数量分类

Clinical characteristics of children with hemolytic uremic syndrome in Hangzhou, China

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World Journal of Pediatrics 2017年第2期13卷 183-185页

作者： Shui-Ai Zhao Bo-Tao ning Jian-Hua mao Department of Nephrology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of PICU Children's HospitalZhejiang University School of MedicineHangzhouChina

Background:Hemolytic uremic syndrome (HUS) is a main cause of acute renal failure in *** study aimed to analyze the clinical characteristics of ***:A retrospective analysis was performed in 46 children with sporadic ***:Of the 46 HUS patients,20 (43.5%) were diarrhea-related HUS,and 26 (56.5%) were atypical ***,edema,oliguria,hemoglobinuria and hypertension were the most common ***,hyponatremia,hypocalcemia,hyperkalemia,metabolic acidosis,increased fibrinogen and hypocomplementemia were found in most *** age of onset (younger than 2 years or not,P=0.009),the duration of oliguria or anuria (more than one week or not,P=0.005),accompanied with extrarenal complications or not (P=0.005),dialysis and plasma exchange (P=0.04) were associated with the mortality ***:The age of onset younger than 2 years,oliguria/anuria more than 1 week,and associated with extrarenal complications were predictive factors of poor prognosis.

关键词： hemolytic uremic syndrome prognosis therapy

Role of radiomics in the diagnosis and treatment of gastrointestinal cancer

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World Journal of Gastroenterology 2022年第42期28卷 6002-6016页

作者： Qi mao mao-Ting Zhou Zhang-Ping Zhao ning Liu Lin Yang Xiao-Ming Zhang Department of Radiology Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Radiology Panzhihua Central HospitalPanzhihua 617000Sichuan ProvinceChina

Gastrointestinal cancer(GIC)has high morbidity and mortality as one of the main causes of cancer *** risk stratification is critical to guide patient management,but traditional imaging studies have difficulty predicting its biological *** emerging field of radiomics allows the conversion of potential pathophysiological information in existing medical images that cannot be visually recognized into high-dimensional quantitative image *** lesion characterization,therapeutic response evaluation,and survival prediction can be achieved by analyzing the relationships between these features and clinical and genetic *** recent years,the clinical application of radiomics to GIC has increased *** this editorial,we describe the latest progress in the application of radiomics to GIC and discuss the value of its potential clinical applications,as well as its limitations and future directions.

关键词： Gastrointestinal cancer Diagnosis Treatment Radiomics Therapeutic response Hepatocellular carcinoma

江苏沿海沉积物有机磷含量、总有机碳、总氮与同位素特征及有机质来源解析

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地球科学与环境学报 2024年第1期46卷 67-80页

作者：严维兵饶文波栗天宁徐祖阳杨宇航茅昌平江苏省地质勘查技术院江苏南京210049 河海大学地球科学与工程学院江苏南京211100

沉积物有机质分布与来源是海陆过渡带生物地球化学循环和沿海生态环境研究中的重点和难点问题,一直受到广泛关注。选择江苏沿海为研究区域,于2016年采集61个表层沉积物样品,查明其中的有机磷(OP)含量、总有机碳(TOC)、总氮(TN)及有机碳... 详细信息

沉积物有机质分布与来源是海陆过渡带生物地球化学循环和沿海生态环境研究中的重点和难点问题,一直受到广泛关注。选择江苏沿海为研究区域,于2016年采集61个表层沉积物样品,查明其中的有机磷(OP)含量、总有机碳(TOC)、总氮(TN)及有机碳和总氮同位素(δ^(13)C_(org)、δ^(15)N_(tot))特征,试图阐明江苏沿海沉积物有机质来源。结果表明:沉积物有机磷含量、总有机碳、总氮与粒度之间存在显著的相关关系,明显受水动力作用的影响。元素比值与同位素的定性分析表明,沉积物有机质主要由海洋生物提供,也受陆源输入的影响。同位素混合模型计算结果进一步发现,海源对沿海沉积物有机质平均贡献比例达到56.9%,其次为陆源C3植物、土壤以及农业肥料,平均贡献比例为38.5%,生活污水的贡献比例仅为4.6%。海源有机质通过洋流和潮波输送至江苏沿海,而河流输入和沿海养殖可能是陆源输入的重要方式。尽管陆源输入不是江苏沿海沉积物有机质的主要贡献来源,但可能是沿海水体富营养化的驱动因子。

关键词：沉积物有机质有机磷有机碳总氮稳定同位素物质来源江苏

Electromagnetic spectrum chipless radio frequency identification:A review

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Digital Communications and Networks 2020年第3期6卷 377-388页

作者： Qingjuan Li Rana Sadaf Anwar Huansheng ning Jun Wang Lingfeng mao School of Computer and Communication Engineering University of Science and TechnologyBeijing100083China Beijing Engineering Research Center for Cyberspace Data Analysis and Applications Beijing100083China Beijing Electro-Mechanical Engineering Institute Beijing100074China

Over the past few years,Radio Frequency IDentification(RFID)has stridden significantly due to its adoption in many business and daily life *** empowers end-to-end and item-by-item visibility,letting the customers or decision-makers effectively trail the personnel and resources for improved *** research and development in this area have transformed the inexpensive,miniaturized technology of RFIDs without chip *** Radio Frequency IDentification(CRFID)is a unique wireless technology based on radar principle to sense,identify,and track the *** are simplified and miniaturized tags of traditional RFID,which can widely be used in small and cheap objects/applications in our daily *** paper reviews the definition,principle,and most recent development in *** on the reported researches,the ElectroMagnetic Spectrum(EMS)method is typical,which has been concerned by many RFID ***,this paper reviews different types of EMS CRFID tag and classifies these tags based on structure design emphasizing their significant geometries in comparison with performance *** and coding methods of the EMS CRFID are also elaborated,contrasting the tag capacity and coding ***,we briefly summarize the challenges and limitations in this emerging field and look forward to the prospects of future CRFID.

关键词： CRFID Electromagnetic Tag structure Coding

基于ADAMS的PUMA560机器人运动学研究

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唐山师范学院学报 2024年第3期46卷 73-77页

作者：王宁国石宝玉程茂胜安徽莱恩电泵有限公司技术部安徽宁国242300 安徽工业大学机械工程学院安徽马鞍山243032

在建立PUMA560机器人模型的基础上,通过D-H坐标系对模型进行运动学理论分析,推导出相关公式,并将关节角度代入以得到末端姿态的理论值。以世界上著名的机械系统仿真软件ADAMS作为分析平台,通过在ADAMS中导入模型并进行相关仿真并得到仿... 详细信息

在建立PUMA560机器人模型的基础上,通过D-H坐标系对模型进行运动学理论分析,推导出相关公式,并将关节角度代入以得到末端姿态的理论值。以世界上著名的机械系统仿真软件ADAMS作为分析平台,通过在ADAMS中导入模型并进行相关仿真并得到仿真数据,将其与理论值相比较。通过数据处理可以得知,PUMA560机器人的运动学误差相对较小,机器人可以达到预期的动作效果。

关键词：机器人仿真运动学 ADMAS

黄河上游兰州段SCCPs污染特征及来源解析

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中国环境科学 2024年第5期44卷 2526-2533页

作者：程景隆贾柠屹胡柏丞郭雨轩宋世杰赵渊毛潇萱兰州大学资源环境学院甘肃省环境污染预警与控制重点实验室甘肃兰州730000

对黄河上游兰州段2023年枯水期和丰水期水环境中短链氯化石蜡(SCCPs)的污染特征、来源和生态风险展开调查.研究区水相、悬浮颗粒相和沉积物中SCCPs浓度水平分别为116.04~1057.74ng/L、1.89~68.93μg/g(干重)和121.65~428.97ng/g(干重).... 详细信息

对黄河上游兰州段2023年枯水期和丰水期水环境中短链氯化石蜡(SCCPs)的污染特征、来源和生态风险展开调查.研究区水相、悬浮颗粒相和沉积物中SCCPs浓度水平分别为116.04~1057.74ng/L、1.89~68.93μg/g(干重)和121.65~428.97ng/g(干重).水相中SCCPs浓度丰水期高于枯水期,而悬浮颗粒相中SCCPs浓度枯水期则要高于丰水期,沉积物中SCCPs浓度在主要排污口下游以及河流较缓处枯水期高于丰水期,研究区可能存在丰水期排污量增加的情况;SCCPs同系物以C_(10)、C_(11)组分和Cl_(5-7)组分占比最高.研究区SCCPs污染可能主要源于CPs产品的生产和使用以及大气迁移传输,其污染贡献率分别为67.21%和32.79%.根据加拿大环境部的风险判定标准,研究区河水和沉积物中SCCPs污染暂未构成显著的生态风险,但悬浮颗粒相中SCCPs较高的浓度需得到应有的重视.

关键词：黄河短链氯化石蜡来源解析生态风险