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传感器并联型局部放电监测与定位方法

电工技术学报 2014年第2期29卷 226-230页

作者：高鹏路胡岳刘斌曹灵钰江秀臣盛戈皞电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海200240 山东电力集团公司威海供电公司威海264200

局部放电监测作为绝缘诊断的重要手段,因其能在早期及时有效地发现电气设备的绝缘缺陷,正为电力部门所推广。然而目前变电站局部放电在线监测都是针对单个设备进行的,要对变电站多设备实施监测,需要安装多个监测装置,存在成本高、系统... 详细信息

局部放电监测作为绝缘诊断的重要手段,因其能在早期及时有效地发现电气设备的绝缘缺陷,正为电力部门所推广。然而目前变电站局部放电在线监测都是针对单个设备进行的,要对变电站多设备实施监测,需要安装多个监测装置,存在成本高、系统维护工作量大等问题。本文提出了一种基于传感器并联结构的低成本变电站多设备局部放电监测与初定位方法。该方法通过在一环状信号总线上并联多个安装在不同设备的局部放电传感器,达到仅用一套采集系统监控多个设备的目的,同时利用各个传感器所检测的局部放电脉冲信号到达信号总线两端的时差固定且各自不同,实现局部放电源的初定位。在阐述该新型局部放电监测与初定位原理基础上,本文还对实现该原理的监测系统结构、定位算法进行了初步研究,并进行了实验验证。

关键词：局部放电传感器并联检波信号到达时间差定位 partial discharge (PD) time difference of arrival(TDOA)

Isometric 3D Shape partial Matching Using GD-DNA

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Journal of Computer Science & Technology 2018年第6期33卷 1178-1191页

作者： Guo-Guang Du Cong-Li Yin Ming-Quan Zhou Zhong-Ke Wu Ya-Chun Fan Fu-Qing Duan Peng-Bo Zhou College of Information Science and Technology Beijing Normal University Beijing 100875 China Engineering Research Center of Virtual Reality and Applications Ministry of Education Beijing 100875 China

Isometric 3D shape partial matching has attracted a great amount of interest, with a plethora of applicationsranging from shape recognition to texture mapping. In this paper, we propose a novel isometric 3D shape partial matchingalgorithm using the geodesic disk Laplace spectrum （GD-DNA）. It transforms the partial matching problem into the geodesicdisk matching problem. Firstly, the largest enclosed geodesic disk extracted from the partial shape is matched with geodesicdisks from the full shape by the Laplace spectrum of the geodesic disk. Secondly, Generalized Multi-Dimensional Scalingalgorithm （GMDS） and Euclidean embedding are conducted to establish final point correspondences between the partialand the full shape using the matched geodesic disk pair. The proposed GD-DNA is discriminative for matching geodesicdisks, and it can well solve the anchor point selection problem in challenging partial shape matching tasks. Experimentalresults on the Shape Retrieval Contest 2016 （SHREC＇16） benchmark validate the proposed method, and comparisons withisometric partial matching algorithms in the literature show that our method has a higher precision.

关键词： isometric partial matching geodesic disk Laplace spectrum

partial Differential Equations and Continuum Mechanics:a Collection of Papers Dedicated to Professor Philippe G. Ciarlet on the Occasion of His 80th Birthday

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Acta Mathematicae Applicatae Sinica 2019年第1期35卷 1-2页

作者： Cristinel MARDARE Tong YANG 不详

Preface This Special Issue in'Acta Mathematicae Applicatae Sinica(English Series)'gathers peer reviewed papers dedicated to Professor Philippe G.Ciarlet on the occasion of his eightieth birthday.Written by friends and colleagues from France and Hong Kong/China,they stand as a testimony of their admiration for an exceptional human being and mathematician.

关键词： partial Differential Equations Continuum Mechanics

Forward and Backward Mean-Field Stochastic partial Differential Equation and Optimal Control

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Chinese Annals of Mathematics,Series B 2019年第4期40卷 515-540页

作者： Maoning TANG Qingxin MENG Meijiao WANG Department of Mathematical Sciences Huzhou UniversityHuzhou 313000ZhejiangChina Department of Mathematical Sciences Huzhou UniversityHuzhou 313000ZhejiangChina Business School University of Shanghai for Science and TechnologyShanghai 200093China

This paper is mainly concerned with the solutions to both forward and backward mean-field stochastic partial differential equation and the corresponding optimal control problem for mean-field stochastic partial differential equation. The authors first prove the continuous dependence theorems of forward and backward mean-field stochastic partial differential equations and show the existence and uniqueness of solutions to them. Then they establish necessary and sufficient optimality conditions of the control problem in the form of Pontryagin’s maximum principles. To illustrate the theoretical results, the authors apply stochastic maximum principles to study the infinite-dimensional linear-quadratic control problem of mean-field type. Further, an application to a Cauchy problem for a controlled stochastic linear PDE of mean-field type is studied.

关键词： Mean-field Stochastic partial differential equation Backward stochastic partial differential equation Optimal control Maximum principle Adjoint equation

Complete or partial split in associating liver partition and portal vein ligation for staged hepatectomy: A systematic review and meta-analysis

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World Journal of Gastroenterology 2019年第39期25卷 6016-6024页

作者： Han-Chun Huang Jin Bian Yi Bai Xin Lu Yi-Yao Xu Xin-Ting Sang Hai-Tao Zhao Department of Liver Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College

BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)has been adopted by liver surgeons in recent years.However,high morbidity and mortality rates have limited the promotion of this technique.Some recent studies have suggested that ALPPS with a partial split can effectively induce the growth of future liver remnant(FLR)similar to a complete split with better postoperative safety profiles.However,some others have suggested that ALPPS can induce more rapid and adequate FLR growth,but with the same postoperative morbidity and mortality rates as in partial split of the liver parenchyma in ALPPS(p-ALPPS).AIM To perform a systematic review and meta-analysis on ALPPS and p-ALPPS.METHODS A systematic literature search of PubMed,Embase,the Cochrane Library,and ClinicalTrials.gov was performed for articles published until June 2019.Studies comparing the outcomes of p-ALPPS and ALPPS for a small FLR in consecutive patients were included.Our main endpoints were the morbidity,mortality,and FLR hypertrophy rates.We performed a subgroup analysis to evaluate patients with and without liver cirrhosis.We assessed pooled data using a random-effects model.RESULTS Four studies met the inclusion criteria.Four studies reported data on morbidity and mortality,and two studies reported the FLR hypertrophy rate and one study involved patients with cirrhosis.In the non-cirrhotic group,p-ALPPS-treated patients had significantly lower morbidity and mortality rates than ALPPStreated patients[odds ratio(OR)=0.2;95%confidence interval(CI):0.07–0.57;P=0.003 and OR=0.16;95%CI:0.03-0.9;P=0.04].No significant difference in the FLR hypertrophy rate was observed between the two groups(P>0.05).The total effects indicated no difference in the FLR hypertrophy rate or perioperative morbidity and mortality rates between the ALPPS and p-ALPPS groups.In contrast,ALPPS seemed to have a better outcome in the cirrhotic group.CONCLUSION The findings of our study suggest that p-ALPPS is safer than ALPPS in patients without

关键词： Liver,Cancer partial split Staged hepatectomy Systematic review Metaanalysis

Clinical outcomes and safety of high-resolution manometry guided superficial partial circular muscle myotomy in per-oral endoscopic myotomy for Jackhammer esophagus: Two cases report

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World Journal of Clinical Cases 2019年第16期7卷 2322-2329页

作者： Youn I Choi Kyoung Oh Kim Dong Kyun Park Jun-Won Chung Yoon Jae Kim Kwang An Kwon Department of Gastroenterology Gil Medical Center Gachon University

BACKGROUND Jack hammer esophagus is a relatively rare disease and to date,there is no dramatic treatment option.Recently,conventional per-oral endoscopic myotomy (POEM) have expanded their area into Jackhammer esophagus.However,several complications such as post procedure motility disorders (e.g.,passage disturbance) are issues after POEM.To overcome these issues,we here introduced high-resolution manometry (HRM)-guided superficial partial circular muscle myotomy,which involves cutting only the superficial layer of the esophageal circular muscle.CASE SUMMARY We report two cases of patients with Jackhammer esophagus who were treated with HRM-guided extremely superficial partial circular muscle myotomy during POEM.Case 1 was a 53-year-old female with medication-refractory odynophagia and case 2 was a 47-year-old man who presented with chest pain.They were diagnosed with Jackhammer esophagus using HRM,and the hypercontractile segments of the esophagus were identified.HRM-guided extremely superficial partial circular muscle myotomy was performed while preserving the lower esophageal sphincter.Therefore,the circular and longitudinal muscle layers are preserved but hypercontractile movements are reduced,even after POEM.Patients’ clinical symptoms dramatically improved right after POEM,and 6-mo follow-up HRM revealed completely resolved status.During a 1-year follow-up period,patients were still in good health and remained symptom free.CONCLUSION HRM-guided superficial partial circular muscle myotomy may be a promising alternative to conventional POEM for treating Jackhammer esophagus with improved efficacy.

关键词： Jackhammer esophagus Hypercontractile partial circular muscle myotomy Case report

Accelerated partial breast irradiation:advances and controversies

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Chinese Journal of Cancer 2016年第4期35卷 163-170页

作者： Mani Akhtari Bin S.Teh Department of Radiation Oncology Houston Methodist HospitalCancer Center and Research InstituteWeil Cornell Medical College Department of Radiation Oncology The University of Texas Medical Branch at Galveston

The management of localized breast cancer has changed dramatically over the past three to four decades.Breastconserving therapy,which involved lumpectomy followed by adjuvant irradiation,is now widely considered the standard of care in women with early-stage breast cancer.Accelerated partial breast irradiation(APBI),which involves focal irradiation of the lumpectomy cavity over a short period of time,has developed over the past two decades as an alternative to whole breast irradiation(WBI).Multiple APBI modalities have been developed including brachytherapy,external beam irradiation,and intraoperative irradiation.These new technigues have provided early-stage breast cancer patients with shorter treatment duration and more focused irradiation,delivering very high biological doses to the region at a high risk of failures over a much shorter treatment course as compared with conventional radiotherapy.However,the advantages of APBI over conventional radiotherapy are controversial,including a higher risk of complications reported in retrospective literature and shorter follow-up duration in the intraoperative APBI trials.Nevertheless,APBI presents a valuable alternative to WBI for a selected population of women with early-stage breast cancer.

关键词： Accelerated partial breast irradiation Brachytherapy Breast cancer

一种partial EIV半参数模型的系统误差处理方法

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测绘学报 2018年第1期47卷 25-34页

作者：王乐洋熊露雲东华理工大学测绘工程学院江西南昌330013 流域生态与地理环境监测国家测绘地理信息局重点实验室江西南昌330013 江西省数字国土重点实验室江西南昌330013

在使用总体最小二乘求解参数时,若观测值中包含系统误差,此时得到的参数估值则会受到系统误差的影响,从而得到不可靠的解,因此必须削弱系统误差对参数估计的影响,以获得相对可靠的解。本文提出在partial errors-in-variables(partial E... 详细信息

在使用总体最小二乘求解参数时,若观测值中包含系统误差,此时得到的参数估值则会受到系统误差的影响,从而得到不可靠的解,因此必须削弱系统误差对参数估计的影响,以获得相对可靠的解。本文提出在partial errors-in-variables(partial EIV)模型的基础上给观测值增加非参数部分(系统误差),从而构建partial EIV半参数模型;基于补偿最小二乘准则进行公式推导,并分别通过选取适当的正则化矩阵及通过L曲线法确定平滑因子。通过算例结果分析表明,与传统方法相比,本文的方法在一定程度上能够削弱系统误差的影响,得到更为可靠的参数解,从而验证了该方法的有效性和可行性。

关键词： partial EIV半参数模型系统误差正则化矩阵 L曲线平滑因子

Influence of partial Coherent Light on the Transmission Spectrum and Goos-H?nchen Shift in Rydberg Atomic Medium

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Communications in Theoretical Physics 2019年第3期71卷 281-286页

作者： Dilawar Ali Muhammad Umer Iftikhar Muqaddar Abbas Ziauddin Quantum Optics Laboratory Department of Physics COMSATS University

A cold atomic medium(Rydberg medium) with cascade configuration under the blockade mechanism is considered. A partial coherent light(PCL) beam is incident on the medium, which makes an angle θ with z-axis. We study the influence of PCL field on the transmission spectrum and find high transmission of probe field for PCL field.Conversely, it is investigated that the transparency of probe field decrease for coherent light field. The transmission of probe field is also studied via beam width of PCL field and investigated high transmission of probe field for small beam width and vice versa. Interestingly, the Goos-H?nchen shift(GHS) in the transmitted light(TL) is studied for PCL field. Large negative and positive GHS in the TL are investigated for PCL field and small beam width of PCL field.

关键词： partial coherent light transmission spectrum Goos-Hanchen shift