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接收机钟差估计的伪距异常值检测方法

中国惯性技术学报 2017年第6期25卷 743-747页

作者：饶爱水何剑伟李永刚李清梅汪毅张龙中国卫星海上测控部江阴214431

针对接收机钟差辅助的RAIM检测方法无法适应接收机钟差周期性跳变的问题,根据伪距单点定位原理,提出了基于接收机钟差估计的伪距异常值检测方法。首先根据接收机钟差最大值、接收机速度以及两次定位时间差实时计算伪距异常值的核检门限... 详细信息

针对接收机钟差辅助的RAIM检测方法无法适应接收机钟差周期性跳变的问题,根据伪距单点定位原理,提出了基于接收机钟差估计的伪距异常值检测方法。首先根据接收机钟差最大值、接收机速度以及两次定位时间差实时计算伪距异常值的核检门限,然后依次判断每颗卫星到接收机的伪距数据是否正常;为保证检测效果,提出了接收机采样周期门限和定位时间差门限的计算方法,理论计算表明,当接收机钟差最大值为12?s、速度达到第二宇宙速度时,接收机采样周期应小于0.32 s,定位时间差应小于3.2 s。采用GPS空间服务空域高动态目标实测数据分析,结果表明:该方法不受接收机钟差本地周期性修正的影响,在卫星数量减少至4颗或5颗时,依然可以识别出伪距异常的卫星,超出核检门限的伪距异常值识别率达100%,异常数据剔除后的伪距单点定位精度最大值达36 m。

关键词：钟差时钟跳变伪距接收机自主完好性检测故障检测故障识别

Theoretical Analysis of a Vertical Channel Dropping Tunnelling Process in a Photonic Crystal for Wavelength Division Demultiplexing

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Chinese Physics Letters 2001年第12期18卷 1613-1616页

作者： FU jian he Sai-Ling XIAO San-shui QIU Min he jian-Jun Centre for Optical and Electromagnetic Research State Key Laboratory for Modern Optical InstrumentationZhejiang UniversityHangzhou 310027 Department of Electromagnetic Theory Royal Institute of TechnologyS-10044 StockholmSweden

A theoretical analysis is presented for a channel drop tunnelling structure composed of a horizontal input channel, a vertical output channel and a multi-mode cavity in a photonic crystal. Criteria for a complete transfer are derived for applications of wavelength division demultiplexing. The analytical results are verified with a numerical simulation using a finite difference time domain method. The vertical channel dropping tunnelling system makes the demultiplexing device much more compact, as compared to the conventional parallel channel dropping system.

关键词： channel multiplexing Crystal

Improved track-before-detect method for detecting range-spread targets in generalized Pareto clutter

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Science China(Information Sciences) 2019年第4期62卷 44-46页

作者： jian XUE Shuwen XU Penglang shui National Lab of Radar Signal Processing Collaborative Innovation Center of Information Sensing and UnderstandingXidian University Department of Electrical and Computer Engineering Mcmaster University

Dear editor,High-resolution radars demonstrate a good targetdetection performance, especially for weak targets such as periscopes and small boats [1]. Methods for adaptive detection employed by high-resolution

关键词： TBD Improved track-before-detect method for detecting range-spread targets in generalized Pareto clutter SCR

One-pot Synthesis and Formation Mechanism of Prisms-built VO2(M) with Hypersensitive Phase-transition Hysteresis

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Chinese Journal of Structural Chemistry 2021年第8期40卷 999-1004,968页

作者： LI Xiong-jian YANG shui-Jin Hubei Key Laboratory of Pollutant Analysis&Reuse Technology College of Chemistry and Chemical EngineeringHubei Normal UniversityHuangshi 435002China

Prisms-built VO_(2)(M)micro-nanostructures with narrow hysteresis width of 2.7℃were successfully synthesized using V_(2)O_(5)-H_(2)C_(2)O_(4)-H2O system by one-pot hydrothermal *** structure,composition,phase transition and optical properties were characterized by XRD,SEM,DSC,and variable-temperature *** results revealed the prism had well-defined six facets and entire smooth surface with lengths of about 500 nm and thicknesses of around 100 *** prisms were connected to each other through the apical *** prismatic VO_(2)(M)showed excellent phase transition and optical switching properties that would be beneficial for highly sensitive electrical/optical devices or other *** possible formation mechanism of prismatic VO_(2)(M)was proposed via time-dependent SEM images and XRD ***,the influence of the amount of H_(2)O on the final product was discussed in detail.

关键词： VO_(2)(M) optical properties hysteresis width one-pot synthesis

A Parallel Genetic Algorithm Based on Spark for Pairwise Test Suite Generation

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Journal of Computer Science & Technology 2016年第2期31卷 417-427页

作者： Rong-Zhi Qi Zhi-jian Wang shui-Yan Li College of Computer and Information Hohai University Nanjing 211106 China CoUege of Science Hohai University Nanjing 211106 China

Pairwise testing is an effective test generation technique that requires all pairs of parameter values to be by at least one test case. It has been proven that generating minimum test suite is an NP-complete problem covered Genetic algorithms have been used for pairwise test suite generation by researchers. However, it is always a time-consuming process, which leads to significant limitations and obstacles for practical use of genetic algorithms towards large-scale test problems. Parallelism will be an effective way to not only enhance the computation performance but also improve the quality of the solutions. In this paper, we use Spark, a fast and general parallel computing platform, to parallelize the genetic algorithm to tackle the problem. We propose a two-phase parallelization algorithm including fitness evaluation parallelization and genetic operation parallelization. Experimental results show that our algorithm outperforms the sequential genetic algorithm and competes with other approaches in both test suite size and computational performance. As a result, our algorithm is a promising improvement of the genetic algorithm for pairwise test suite generation.

关键词： pairwise testing parallel genetic algorithm Spark test generation

Development and Evaluation of a Wearable Lower Limb Rehabilitation Robot

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Journal of Bionic Engineering 2022年第3期19卷 688-699页

作者： Wanting Li Keping Liu Chunxu Li Zhongbo Sun shui Liu jian Gu Department of Control Engineering Changchun University of TechnologyChangchun130012China Centre for Robotics and Neural Systems University of PlymouthPlymouthPL48AAUK School of Mechatronical Engineering Changchun University of TechnologyChangchun130012China

This paper introduces a rigid-flexible coupling wearable exoskeleton robot for lower limb,which is designed in light of gait biomechanics and beneficial for low limb movement disorders by implementing gait *** rationality of the proposed mechanism is shown with the implementation of the dynamic simulation through MSC *** the purposes of lightweight,the exoskeleton mechanism is optimized through finite element *** can be concluded from performance evaluation experiment,the mechanism has certain advantages over existing exoskeleton robots,namely,comfortable,lightweight,low cost,which can be utilized for rehabilitation training in medical institutions or as a daily-walking ancillary equipment for patients.

关键词： Wearable rehabilitation robot Biomechanics Robot mechanism design Virtual analysis

Rare earth elemental and Sr isotopic evidence for seawater intrusion event of the Songliao Basin 91 million years ago

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Petroleum Science 2023年第3期20卷 1347-1362页

作者： Yu-Ke Liu Hua-jian Wang Jin-You Zhang Zhen-Wu Liu Fa-Zi Chen Xiao-Mei Wang shui-Chang Zhang he Liu Research Institute of Petroleum Exploration and Development Beijing100083China Key Laboratory of Petroleum Geochemistry China National Petroleum CorporationBeijing100083China Daqing Oil Field Company China National Petroleum CorporationDaqingHeilongjiang163000China School of Ocean Sciences China University of GeosciencesBejing100083China

Petrogenesis of lacustrine dolostone is closely related with paleo-lake water *** we report the high spatial-resolution petrographic and geochemical results of a lacustrine dolomite nodule from the Qingshankou Formation,the Songliao *** and elemental signatures confirm the protogenetic origin of this nodule and its effectiveness in recording geochemical characteristics of paleo-lake water during *** low Y/Ho ratios,middle rare earth element(MREE)enrichment and subtle positive Eu anomalies within the nodule indicate a fresh water ***,the Sr isotope values in the core of the nodule(0.7076-0.7080)are close to contemporaneous seawater(0.7074),yet different from the modern river(0.7120)and the host black shale(0.7100).On the premise of excluding the influence of hydrothermal fluids,the significantly low strontium isotope values of the lacustrine dolomite might be caused by seawater interference during *** findings demonstrate that lacustrine dolomite within black shales is not only a faithful tracer of diagenetic water environment,but also a novel and easily identified mineralogical evidence for episodic seawater intrusion event(91 Ma)in the Songliao Basin,which supplements other paleontological and geochemical evidence.

关键词： Songliao Basin Lacustrine dolostone Seawater intrusion Rare earth elements Strontium isotope

Treatment of extracranial internal carotid artery dissecting aneurysm with SUPERA stent implantation:Two case reports

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World Journal of Clinical Cases 2022年第5期10卷 1602-1608页

作者： Min-jian Qiu Bao-Rong Zhang shui-jiang Song Department of Neurology The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND There is no standard endovascular treatment for extracranial internal carotid artery dissecting *** the past,stent-graft isolation and stent-assisted coil embolization were commonly used for wide-necked and fusiform ***,we present two cases of extracranial internal carotid artery dissecting aneurysms treated successfully using the SUPERA *** SUMMARY Case 1 was a 57-year-old male patient with sudden right limb weakness and vague speech and diagnosed with cerebral infarction in February *** computed tomographic angiography(CTA)revealed left internal carotid artery dissection with *** at 2 mo showed an eccentric wide-necked dissecting aneurysm(5 mm×5 mm×12 mm,10-mm neck)that was enlarged at 4 mo(7 mm×6 mm×12 mm,11-mm neck).The patient underwent SUPERA stent *** condition was stable in July *** 2 was a 57-year-old man who suddenly felt dizzy and developed unsteady walking in November *** CTA suggested right internal carotid artery dissecting aneurysm(11 mm×9 mm×31 mm)complicated with severe lumen stenosis(95%).The patient underwent SUPERA stent *** patient had no residual symptoms and was stable in December *** SUPERA stent implantation might achieve good results in treating wide-necked or long fusiform internal carotid artery dissecting aneurysms.

关键词： Extracranial Internal carotid artery Dissecting aneurysm Stent Case report

Da Vinci robot-assisted pancreato-duodenectomy in a patient with situs inversus totalis:A case report and review of literature

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World Journal of Gastrointestinal Oncology 2022年第7期14卷 1363-1371页

作者： Bai-Bei Li Shi-Liu Lu Xiang he Biao Lei jian-Ni Yao Si-Chen Feng shui-Ping Yu Department of hepatobiliary Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Situs inversus totalis(SIT)is an extremely rare congenital malformation characterized by mirror displacement of the thoracoabdominal organs such as the heart,liver,spleen,and ***,we describe a patient with SIT complicated with cholangiocarcinoma who underwent successful pancreaticoduodenectomy with the assistance of a da Vinci *** SUMMARY A 58-year-old female presented to the hospital with paroxysmal pain in her left upper abdomen,accompanied by jaundice and staining of the sclera as chief *** examination detected a mass at the distal end of the common bile duct,with inverted thoracic and abdominal *** retrograde cholangiopancreatography forceps biopsy revealed the presence of a well-differentiated *** patient successfully underwent robotic-assisted pancreaticoduodenectomy;the operation lasted 300 min,the intraoperative blood loss was 500 mL,and there were no intraoperative and postoperative *** SIT is not directly related to the formation of *** preoperative imaging examination is conducive to disease diagnosis and also convenient for determining the feasibility of tumor ***-assisted pancreaticoduodenectomy for SIT complicated with cholangiocarcinoma provides a safe,feasible,minimally invasive,and complication-free alternative with adequate preoperative planning combined with meticulous intraoperative procedures.

关键词： Situs inversus totalis Cholangiocarcinoma Da Vinci robot Whipple Surgery Case report