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An Overview of Contour Detection Approaches

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International Journal of Automation and computing 2018年第6期15卷 656-672页

作者： Xin-Yi Gong Hu Su De Xu zheng-tao zhang Fei Shen Hua-Bin Yang Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Science Beijing 100190 China University of Chinese Academy of Science Beijing 100049 China Tianjin Intelligent Technology Institute of Institute of Automation Chinese Academy of Science Co.Ltd Tianjin 300300 China

Object contour plays an important role in fields such as semantic segmentation and image classification. However, the extraction of contour is a difficult task, especially when the contour is incomplete or unclosed. In this paper, the existing contour detection approaches are reviewed and roughly divided into three categories： pixel-based, edge-based, and region-based. In addition, since the traditional contour detection approaches have achieved a high degree of sophistication, the deep convolutional neural networks （DCNNs） have good performance in image recognition, therefore, the DCNNs based contour detection approaches are also covered in this paper. Moreover, the future development of contour detection is analyzed and predicted.

关键词： Contour detection contour salience gestalt principle contour grouping active contour.

Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna Ⅱ glacier

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Advances in Climate Change Research 2024年第3期15卷 464-475页

作者： Yao LI Yi-Fei CUI Jian-Sheng HAO zheng-tao zhang Hao WANG Jian GUO Shuo-Fan WANG State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna Ⅱ glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

An Effective On-line Surface Particles Inspection Instrument for Large Aperture Optical Element

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International Journal of Automation and computing 2017年第4期14卷 420-431页

作者： Wen-Dong Ding zheng-tao zhang Da-Peng zhang De Xu Hai-Bing Lv Xin-Xiang Miao Guo-Rui Zhou Hao Liu Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences School of Computer and Control Engineering University of Chinese Academy of Sciences Laser Fusion Research Center China Academy of Engineering Physics

Surface particles growing in large aperture optical element （LAOE） have significant impact on LAOE＇s stable operation. It is a challenge for the online system to inspect the particles with long working distance, enough precision and high efficiency because of the system constraints. In this paper, an effective and portable inspection instrument is designed based on dark-field imaging principle. A Nikon lens and an industrial high definition （HD） camera are selected to construct the vision system to inspect particles of microns size spreading over hundreds of millimeters. Using two motors and other mechanical structure, the system can realize auto-focus and image rectification functions. The line light sources are installed on both sides of the LAOE in a sealed box while the vision system is portable and working outside the box. An adaptive binarization method is proposed to process the captured dark-field image. The distribution of particles on the LAOE＇s surface is investigated. Because of the high resolution of the captured image, the SSE2 instructions optimization method is used to reduce the time cost of the algorithm. Experiments show that the instrument can inspect LAOE effectively and accurately.

关键词： Dark-field imaging image rectification adaptive binarization particle inspection large aperture optical elements(LAOE).

A matched-pair comparison between bilateral intrafascial and interfascial nerve-sparing techniques in extraperitoneal laparoscopic radical prostatectomy

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Asian Journal of Andrology 2013年第4期15卷 513-517,I0009页

作者： tao zheng Xu zhang Xin Ma Hong-Zhao Li jiang-Pin Gao Wei Cai Jun Dong Guang-Fu Chen Bao-Jun Wang tao-Ping Shi Er-Lin Song Wei-Hao Chen Qing-Bo Huang Department of Urology Chinese People's Liberation Army General Hospital Military Postgraduate Medical College Beijing 100853 China

The aim of this study was to validate the advantages of the intrafascial nerve-sparing technique compared with the interfascial nerve-sparing technique in extraperitoneal laparoscopic radical prostatectomy. From March 2010 to August 2011, 65 patients with localized prostate cancer （PCa） underwent bilateral intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. These patients were matched in a 1.2 ratio to 130 patients with localized PCa who had undergone bilateral interfascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy between January 2008 and August 2011. Operative data and oncological and functional results of both groups were compared. There was no difference in operative data, pathological stages and overall rates of positive surgical margins between the groups. There were 9 and 13 patients lost to follow-up in the intrafascial group and interfascial group, respectively. The intrafascial technique provided earlier recovery of continence at both 3 and 6 months than the interfascial technique. Equal results in terms of continence were found in both groups at 12 months. Better rates of potency at 6 months and 12 months were found in younger patients （age 65 years） and overall patients who had undergone the intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. Biochemical progression-free survival rates I year postoperatively were similar in both groups. Using strict indications, compared with the interfascial nerve-sparing technique, the intrafascial technique provided similar operative outcomes and short-term oncological results, quicker recovery of continence and better potency. The intrafascial nerve-sparing technique is recommended as a preferred approach for young PCa patients who are clinical stages cT1 to cT2a and have normal preoperative potency.

关键词： continence interfascial nerve-sparing intrafascial nerve-sparing laparoscopic radical prostatectomy potency prostatecancer (PCa)

Flow Injection Semi-online Preconcentration Graphite Furnace Atomic Absorption Spectrometry for Determination of Cadmium,Copper and Manganese

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Chemical Research in Chinese Universities 2002年第1期18卷 1-7页

作者： zhang Yi-hua, WANG Mei-jia, SU Xing-guang, zheng tao, zhang Han-qi and JIN Qin-han Department of Chemistry, Jilin University, Changchun 130023, P. R. ChinaCHEN YingJilin Environmental Monitoring Centre, Changchun 130011, P. R. China Jilin Univ Dept Chem Changchun 130023 Peoples R China Jilin Environm Monitoring Ctr Changchun 130011 Peoples R China

A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometry that formed an integrated system for the determination of trace amounts of elements. The analytical performances of the prospsed method for determining Cd, Cu and Mn were studied. The analytes were preconcentrated with a thiol resin(Type 190, produced by Nankai University, China) whose active group is -SH. The elements to be determined were preconcentrated onto the column for 60 s and then rinsed with deionized water and eluted with 30 μL of 1 mol/L HCl. The graphite furnace atomic absorption spectrometry(GFAAS) determination of the concentrated analyte was carried out in parallel with the next preconcentration cycle. Enrichment factors 41, 22 and 20 and detection limits(3 σ , n =10) 0.36, 3.8 and 7.0 ng/L for Cd, Cu and Mn, respectively, along with a sampling frequency of 20 h -1 , were obtained with a 60 s loading time at a sample flow rate of 3.5 mL/min. The analytical results for a number of water samples show that the flow-injection semi-online column preconcentration can not only eliminate the effect of some concomitant elements, such as Li, Na, K, Ca and Mg, on the determination of the analyte, but also enhance the sensitivity.

关键词： Flow-injection Semi-online preconcentration Atomic absorption spectrometry,Cadmium,Copper,Manganese

Therapeutic strategy for traumatic instability of subaxial cervical spine

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Chinese Medical Journal 2008年第15期121卷 1364-1368页

作者： CAO Peng LIANG Yu GONG Yao-cheng zheng tao zhang Xin-kai WU Wen-jian Department of Orthopaedics Rui Jin Hospital Shanghai Jiao Tong University School of Medicine Shanghai Institute of Traumatology and Orthopaedics Shanghai 200025 China

Background A simple, safe and effective therapeutic strategy for traumatic instability of the subaxial cervical spine, as well as its prognostic assessment, is still controversial. Methods The therapeutic options for 83 patients of traumatic instability of the subaxial cervical spine, whose average age was 35 years, were determined, according to the Allen-Ferguson classification, general health and concomitant traumatic conditions, neurological function, position of compression materials, concomitant traumatic disc herniation/damage, concomitant locked-facet dislocation, the involved numbers and position, and the patients＇ economic conditions. An anterior, posterior or combination approach was used to decompress and reconstruct the cervical spine. No operations with an anterior-posterior-anterior approach were performed. Results The average follow-up was three years and nine months. Distraction-flexion and compression-flexion were the most frequent injury subtypes. There were 46, 28 and 9 cases of anterior, posterior and combination operations, respectively. The average score of the Japanese Orthopaedics Association, visual analog scale and American Spinal Cord Injury Association （ASIA） motor index improved from 11.2, 7.8 and 53.5, respectively, before operation, to 15.3, 2.6 and 67.8, respectively, at final follow-up. For incomplete spinal cord injury （SCI）, the average ASIA neurological function scale was improved by 1-2 levels. Patients with complete SCI had no neurological recovery, but recovery of nerve root function occurred to different extents. After surgery, radiological parameters improved to different extents. Fusion was achieved in all patients and 12 developed complications. Conclusions The best surgical strategy should be determined by the type of subaxial cervical injury, patients＇ general health, local pathological anatomy and neurological function.

关键词： cervical instability disease classification surgical strategy

Clinical Analysis of 13 Cases with Burkitt Lymphoma or Burkittlike Lymphoma

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Clinical oncology and cancer researeh 2010年第2期7卷 110-115页

作者： Ning-jing LIN Wen zheng Yun-tao zhang Xiao-pei WANG Yu-qin SONG Yan XIE Mei-feng TU Ling-yan PING Jun ZHU Department of Lymphoma Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Peking University School of Oncology Beijing Cancer Hospital and Institute Beijing 100142 China.

OBJECTIVE To summarize the clinical characteristics and treatment effects of Burkitt lymphoma （BL） and Burkitt-like lymphoma （BLL）, and to explore the best possible optimal regimens and the treatment-related *** Clinical data of 13 BL and BLL patients, who were pathologically diagnosed and treated in the Beijing Cancer Hospital from August 1996 to October 2008, were retrospectively analyzed, All patients received the therapeutic regimen with chemotherapy as the first-line treatment. The treatment effect and adverse reactions were *** Of the 13 patients, 12 were men and 1 was woman, with a median age of 15 years （range, 11-62）. Three of the patients were in stage Ⅰ, 2 in stage Ⅱ, 2 in stage Ⅲ, and 6 in stage Ⅳ. Advanced cases were 8 （stage Ⅲ and Ⅳ）, accounting for 61.5% of the patients. Bone marrow involvement was found in 2 cases （15.4%） and central nervous system invasion in 4 （30.8%） at the beginning of the treatment. The common involved sites included the superficial lymph nodes （61.5%）, abdominal organs （53.8%）, and abdominal and retro-peritoneal lymph nodes （38.5%）. B symptoms were observed in 7 patients （53.8%）. Serum lactate dehydrogenase （LDH） level was increased in 8 of the 10 patients who underwent the serum LDH determination, while serum uric acid level was increased in 1 of the 10. Pathological diagnosis showed that 11 of the cases were BL and 2 BLL. Of the 13 patients, 11 （84.6%） achieved a complete remission （CR） or CR/unconfirmed （CRu）, and 1 （7.7%） a partial remission （PR）, with a total responsive rate of 92.3%. At a median follow-up of 8 months （range 5-35）, 6 patients were found dead at the end of the follow-up. One of the 13 patients was lost to the follow-up. The 1-year overall survival, progression-free survival and disease-free survival rates were 56.98%, 32.31% and 39.77%, respectively. The grade-Ⅲ or Ⅳ myelosuppression was found in 9 patients during the chemotherapy （69.2%）, and tumor lysis syndrome and grade-

关键词： Burkitt lymphoma invasion biomedicalresearch drug therapy combination.

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考古测年新方法探析

陕西师范大学学报（自然科学版） 2008年第S1期36卷 136-137页

作者：郑涛张琛西北大学光子学与光子技术研究所陕西西安710069

提出了一种新的同位素检测方法,即利用简并四波混频非线性技术来确定矿物中同位素的含量,以达到测定岩石年龄的目的。此方法精度高、成本低、结构紧凑和使用方便,具有一定的实用价值和发展潜力。

关键词：简并四波混频考古同位素检测

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen zheng Liangwei zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment