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基于改进RRT^(*)算法的无人机往返航迹规划

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中国科学:技术科学 2023年第11期53卷 1911-1921页

作者：俞宬陈谋雍可南南京航空航天大学自动化学院南京211106

针对无人机(unmanned aerial vehicle,UAV)在低空复杂未知环境下的航迹规划问题,充分考虑去程与返程过程中信息的不对称特性,本文提出一种UAV往返航迹规划算法.去程规划通过UAV机载设备实时探测不断更新环境信息,并利用改进的B-RRT*(bid... 详细信息

针对无人机(unmanned aerial vehicle,UAV)在低空复杂未知环境下的航迹规划问题,充分考虑去程与返程过程中信息的不对称特性,本文提出一种UAV往返航迹规划算法.去程规划通过UAV机载设备实时探测不断更新环境信息,并利用改进的B-RRT*(bidirectional rapidly-exploring random tree*)算法结合滚动规划生成去程航迹.返程规划根据去程航迹与全局环境信息,限制在由航迹起始点和目标点确定的椭圆子集中进行集中采样,并采用三次B样条插值算法对规划航迹进行平滑处理生成返程航迹.仿真结果表明所研究的改进算法能有效实现去程与返程的航迹规划.最后,搭建四旋翼UAV平台进行UAV避障飞行实验,验证了本文所提算法的有效性.

关键词：无人机 B-RRT*算法滚动规划航迹规划航迹平滑

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基于迁移学习的铣削机器人定位误差补偿方法

机械工程学报 2022年第14期58卷 170-180页

作者：邓柯楠高栋马守东路勇哈尔滨工业大学机电工程学院哈尔滨150000

空间网格补偿法是提高机器人定位误差的有效方法之一,然而由于所需采样位姿多导致误差测量环节非常耗时,为提高机器人定位误差补偿效率,提出了一种机理分析与数据驱动的铣削机器人定位误差补偿方法,基于迁移学习来预测机器人工作空间内... 详细信息

空间网格补偿法是提高机器人定位误差的有效方法之一,然而由于所需采样位姿多导致误差测量环节非常耗时,为提高机器人定位误差补偿效率,提出了一种机理分析与数据驱动的铣削机器人定位误差补偿方法,基于迁移学习来预测机器人工作空间内不同区域的定位误差。首先建立机器人刚柔耦合误差模型,研究立方体与柱体工作空间内不同区域的误差分布特性;之后,考虑误差区域相似性将机器人工作空间分为源域空间与目标域空间,在源域空间基于分级采样策略将完备的机器人采样位姿及误差测量数据作为源域数据,对于目标域空间只需要将少量的采样位姿及误差数据作为目标域数据,源域数据与目标域数据均用于训练高斯过程回归模型,通过基于加权拟合误差的子空间对齐和自适应权重迭代方法提升迁移学习模型预测精度,根据指定机器人位姿参数预测并补偿机器人定位误差;最后,使用KR160铣削机器人系统进行了误差补偿试验以验证该方法的可行性和有效性,试验结果表明,经过补偿后机器人定位误差1.499 mm降低到0.182 mm,所需机器人采样位姿数目减少了70%,使用铣削机器人加工法兰孔,其轮廓误差和位置误差达到0.269 mm和0.331 mm,该方法可以提高补偿效率和机器人定位精度。

关键词：定位误差迁移学习铣削机器人补偿效率耦合误差模型

Measuring County Resilience After the 2008 Wenchuan Earthquake

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International Journal of Disaster Risk Science 2016年第4期7卷 393-412页

作者： Xiaolu Li Nina Lam Yi Qiang kenan Li Lirong Yin Shan Liu Wenfeng Zheng School of Automation University of Electronic Science and Technology of China Department of Environmental Sciences Louisiana State University The Earth Lab University of Colorado Boulder Geographical & Sustainability Sciences Department University of Iowa

The catastrophic earthquake that struck Sichuan Province,China,in 2008 caused serious damage to Wenchuan County and surrounding areas in southwestern *** recent years,great attention has been paid to the resilience of the affected *** study applied the resilience inference measurement(RIM) model to quantify and validate the community resilience of 105 counties in the impacted *** RIM model uses cluster analysis to classify counties into four resilience levels according to the exposure,damage,and recovery *** model then applies discriminant analysis to quantify the influence of socioeconomic characteristics on the county's *** results show that counties located at the epicenter had the lowest resilience,but counties immediately adjacent to the epicenter had the highest resilience *** that were farther away from the epicenter returned to normal resiliency *** variables—including sex ratio,per capita GDP,percent of ethnic minority,and medical facilities—were identified as the most influential characteristics influencing *** study provides useful information to improve county resilience to earthquakes and support decision making for sustainable development.

关键词： China Resilience Resilience inference measurement(RIM) model Vulnerability Wenchuan earthquake

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多旋翼无人机模型预测抗扰避障制导

国防科技大学学报 2022年第4期44卷 32-42页

作者：兰庆湘陈谋雍可南南京航空航天大学自动化学院江苏南京211100

多旋翼无人机的自主避障是完成复杂任务的基础,避障的效果直接影响无人机执行任务的效能。针对存在外部扰动的无人机避障问题,提出了一种基于模型预测的抗扰避障制导律设计方法。通过设计干扰观测器对系统动态中的外部干扰进行了估计,... 详细信息

多旋翼无人机的自主避障是完成复杂任务的基础,避障的效果直接影响无人机执行任务的效能。针对存在外部扰动的无人机避障问题,提出了一种基于模型预测的抗扰避障制导律设计方法。通过设计干扰观测器对系统动态中的外部干扰进行了估计,并基于李雅普诺夫函数方法设计辅助制导律用于建立稳定性约束条件。结合前两者与模型预测控制,在模型预测控制优化求解中考虑无人机与障碍物的关系,根据所设计的制导律求解水平线速度与偏航角速度指令实现无人机的避障。对所提出的避障制导律进行数值仿真和实物飞行验证,结果表明了所提方法的有效性。

关键词：多旋翼无人机避障制导模型预测控制干扰观测器

An Old Story Retold: Loss of G1 Control Defines A Distinct Genomic Subtype of Esophageal Squamous Cell Carcinoma

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Genomics, Proteomics & Bioinformatics 2015年第4期13卷 258-270页

作者： Qiyan Wang Jian Bai Amir Abliz Ying Liu kenan Gong Jingjing Li Wenjie Shi Yaqi Pan Fangfang Liu Shujuan Lai Haijun yang Changdong Lu Lixin Zhang Wei Chen Ruiping Xu Hong Cai yang Ke Changqing Zeng MOE Key Laboratory of Carcinogenesis and Translational Research Laboratory of Genetics Peking UniversityCancer Hospital & Institute Beijing University of Chinese Medicine CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of Genomics Chinese Academy of Sciences University of Chinese Academy of Sciences Anyang Cancer Hospital

Esophageal squamous cell carcinoma （ESCC） has a high mortality rate. To determine the molecular basis of ESCC development, this study sought to identify characteristic genome-wide alterations in ESCC, including exonic mutations and structural alterations. The clinical implications of these genetic alterations were also analyzed. Exome sequencing and verification were performed for nine pairs of ESCC and the matched blood samples, followed by validation with additional sam- ples using Sanger sequencing. Whole-genomc SNP arrays were employed to detect copy number alteration （CNA） and loss of heterozygosity （LOH） in 55 cases, including the nine ESCC samples subjected to exome sequencing. A total of 108 non-synonymous somatic mutations （NSSMs） in 102 genes were verified in nine patients. The chromatin modification process was found to be enriched in our gene ontology （GO） analysis. Tumor genomes with TP53 mutations were signifi- cantly more unstable than those without TP53 mutations. In terms of the landscape of genomic alterations, deletion of 9p21.3 covering CDKN2A/2B （30.9%）, amplification of 1 1q13.3 covering CCND1 （30.9%）, and TP53 point mutation （50.9%） occurred in two-thirds of the cases. These results suggest that the deregulation of the G1 phase during the cell cycle is a key event in ESCC. Furthermore, six minimal common regions were found to be significantly altered in ESCC samples and three of them, 9p21.3, 7p 11.2, and 3p 12.1, were associated with lymph node metastasis. With the high correlation of TP53 mutation and genomic instability in ESCC, the amplification of CCND1, the deletion of CDKN2A/2B, and the somatic mutation of TP53 appear to play pivotal roles via G1 deregulation and therefore helps to classify this cancer into different genomic subtypes. These findings provide clinical significance that could be useful in future molecular diagnoses and therapeutic targeting.

关键词： Esophageal squamous cell carcinoma Genomic subtype somatic mutation Copy number alteration Cell cycle deregulation

Reaching proficiency in laparoscopic splenectomy

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World Journal of Gastroenterology 2009年第32期15卷 4005-4008页

作者： Tarik Zafer Nursal Ali Ezer Sedat Belli Alper Parlakgumus kenan Caliskan Turgut Noyan Department of General Surgery University of BaskentDadaloglu Mah.01200Serin Evler 39.Sk.No.6 Yüregir/AdanaTurkey

AIM:To investigate the proficiency level reached in laparoscopic splenectomy using the learning curve ***:All patients in need of splenectomy for benign causes in whom laparoscopic splenectomy was attempted by a single surgeon during a time period of 6 years were included in the study (n=33). Besides demographics, operation-related variables and the response to surgery were recorded. The patients were allocated to groups of five, ranked according to the date of the operation. Operation duration, complications, postoperative length of stay, conversion to laparotomy and splenic weight were then compared between these ***: There was a significant difference regarding operation times between the groups (P = 0.001). An improvement was observed after the first 5 cases. The learning curve was flat up to the 25th case. Following the 25th case the operation times decreased still further. There was no difference between the groups regarding the other ***: Unlike the widely accepted "L" shape, the learning curve for laparoscopic splenectomy is a horizontal lazy "S" with two distinct slopes. Privileges may be granted after the first 5 cases. However proficiency seems to require 25 cases.

关键词：切除术腹腔镜脾操作时间学习曲线人口统计手术并发症

Manipulating optical vortices using integrated photonics

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Frontiers of Optoelectronics 2016年第2期9卷 194-205页

作者： Ning ZHANG kenan CICEK Jiangbo ZHU Shimao LI Huanlu LI Marc SOREL Xinlun CAI Siyuan YU Photonics Group University of Bristol Bristol BS8 1UB UK State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China School of Engineering University of Glasgow Glasgow G12 8QQ UK

Optical vortices （OVs） refer to a class of cylindrical optical modes with azimuthally varying phase terms arising either from polarization rotation or from the angular projection of the wave vector that at the quantum level corresponds to photon spin or orbital angular momenta. OVs have attracted the attention of researchers in many areas of optics and photonics, as their potential applications range from optical communications, optical manipulation, imaging, sensing, to quantum information. In recent years, integrated photonics has becomes an effective method of manipulating OVs. In this paper, the theoretical framework and experimental progress of integrated photonics for the manipulation of OVs were reviewed.

关键词： optical vortex orbital angular momentum,angular grating micro-ring resonator

Incidence of congenital hemolytic anemias in young cholelithiasis patients

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World Journal of Gastroenterology 2010年第43期16卷 5457-5461页

作者： Ali Ezer Nurkan Torer Tarik Zafer Nursal Ebru Kizilkilic kenan Caliskan Tamer Colakoglu Gokhan Moray Department of General Surgery University of Baskent Department of Hematology University of Baskent

AIM: To clarify the incidence of congenital hemolytic anemias (CHA) in young cholelithiasis patients and to determine a possible screening test based on the results. METHODS: Young cholelithiasis patients (< 35 years) were invited to our outpatient clinic. Participants were asked for comorbidities and family history. The number of gallstones were recorded. Blood samples were obtained to perform a complete blood count, standard Wright-Giemsa staining, reticulocyte count, hemoglobin (Hb) electrophoresis, serum lactate dehydrogenase and bilirubin levels, and lipid profile. RESULTS: Of 3226 cholecystectomy patients, 199 were under 35 years, and 190 with no diagnosis of CHA were invited to take part in the study. Fifty three patients consented to the study. The median age was 29 years (range, 17-35 years), 5 were male and 48 were female. Twelve patients (22.6%) were diagnosed as thalassemia trait and/or ?ron-deficiency anemia. Hblevels were significantly lower (P = 0.046), and mean corpuscular volume (MCV) and hematocrit levels were slightly lower (P = 0.072 and 0.082, respectively) than normal. There was also a significantly lower number of gallstones with the diagnosis (P = 0.007). CONCLUSION: In endemic regions, for young cholelithiasis patients (age under 35) with 2-5 gallstones, the clinician/surgeon should pay attention to MCV and Hb levels as indicative of CHA.

关键词： Cholelithiasis Congenital hemolytic anemia Screening test

基于干扰区间观测器的无人机预设性能着舰飞行控制

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中国科学：信息科学 2022年第9期52卷 1711-1726页

作者：胡伟雍可南陈谋南京航空航天大学自动化学院南京211106

无人机在现代战争中已发挥重要作用,为夺取海域制空权,航母配备无人机是必然趋势.面向无人机着舰的高精度控制要求,本文针对存在建模误差与外部干扰的无人机,在动态面控制框架下提出一种基于干扰区间观测器的无人机预设性能着舰飞行控... 详细信息

无人机在现代战争中已发挥重要作用,为夺取海域制空权,航母配备无人机是必然趋势.面向无人机着舰的高精度控制要求,本文针对存在建模误差与外部干扰的无人机,在动态面控制框架下提出一种基于干扰区间观测器的无人机预设性能着舰飞行控制策略.该策略能够对未知项提供区间估计,在前馈补偿未知项的同时,控制律将根据区间估计的宽度动态调节控制器增益,从而保证无人机的轨迹始终处在着舰轨迹约束范围内.同时,在干扰区间观测器与飞行控制律设计过程中,引入非线性增益,有效地处理了着舰机动中的状态非线性耦合.最后,基于Lyapunov函数方法与不变集理论,给出着舰飞行控制策略的参数设计条件,数值仿真也进一步表明该策略的有效性.

关键词：无人机着舰控制预设性能控制干扰观测器区间观测器