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基于KVM-over-IP的图书馆中心机房服务器远程监控管理系统的构建 被引量:7
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作者 邵晶 阎晓弟 耶健 《大学图书馆学报》 CSSCI 北大核心 2006年第5期47-50,共4页
针对图书馆中心机房在空间、效率、安全、管理与监控等方面存在的问题,引入了KVM-over-IP技术,提出了构建图书馆中心机房服务器远程监控管理系统的解决方案,并在实践中得到了验证。
关键词 KVM—over-IP 远程监控 管理系统 图书馆中心机房
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KVM-over-IP技术及其在图书馆中心机房远程监控管理的应用 被引量:11
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作者 阎晓弟 耶健 邵晶 《现代图书情报技术》 CSSCI 北大核心 2006年第4期87-90,76,共5页
针对高校图书馆中心机房管理现状,引入KVM技术。提出KVM-over-IP技术在图书馆中心机房远程监控管理的解决方案,介绍西安交通大学图书馆中心机房的应用成功案例。
关键词 KVM技术 KVM-over-IP 图书馆中心机房 远程管理
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First report of colonoscopic closure of a gastrocolocutaneous PEG migration with over-the-scope-clip-system 被引量:4
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作者 Reto Bertolini Christa Meyenberger Michael Christian Sulz 《World Journal of Gastroenterology》 SCIE CAS 2014年第32期11439-11442,共4页
Percutaneous endoscopic gastrostomy(PEG) is a common practice for long-term nutrition of patients who are unable to take oral food. We report of an 85-year old man with a history of recurrent larynx carcinoma and hemi... Percutaneous endoscopic gastrostomy(PEG) is a common practice for long-term nutrition of patients who are unable to take oral food. We report of an 85-year old man with a history of recurrent larynx carcinoma and hemicolectomy many years ago due to unknown reason. Laryngectomy was indicated. Preoperatively a PEG was inserted endoscopically after an abdominal ultrasonography without abnormal findings. Few months after PEG insertion, the patient was evaluated for diarrhea and insufficient feeding without signs of infection or peritonism. An upper endoscopy and computed tomography scan confirmed a buried bumper syndrome with migration of the PEG tube into the colon as a rare complication. He underwent successful colonoscopic removal of the internal bumper and closure of the colonic orifice of the fistula with the over-the-scope-clip system(OTSC). OTSC is an endoscopic device for treatment of bleeding, perforation, leak and fistula in the gastrointestinal tract. To the best of our knowledge, this is the first report of the use of OTSC for colonoscopic closure of a gastrocolocutaneous fistula due to a buried bumper syndrome with transcolonic PEG tube migration. 展开更多
关键词 over-the-scope-clip over-the-scope-clip system Enterocutaneous fistula Colon Buried bumper Percutaneous endoscopic gastrostomy Complication MIGRATION
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基于GRE Tunnel的IPv6-over-IPv4的技术实现 被引量:3
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作者 唐灯平 《南京工业职业技术学院学报》 2010年第4期60-62,65,共4页
针对IPv4向IPv6转换的发展趋势,介绍了GRE Tunnel的工作原理以IPv6-over-IPv4技术,并以真实的工程项目的执行为主线贯穿整个实训,包括分析、设计、配置、测试、运行以及维护等过程。最终实现了基于GRE Tunnel的IPv6-over-IPv4隧道技术,... 针对IPv4向IPv6转换的发展趋势,介绍了GRE Tunnel的工作原理以IPv6-over-IPv4技术,并以真实的工程项目的执行为主线贯穿整个实训,包括分析、设计、配置、测试、运行以及维护等过程。最终实现了基于GRE Tunnel的IPv6-over-IPv4隧道技术,将骨干网为IPv4网络,IPv6网络为孤岛的网络互连起来。 展开更多
关键词 IPV6 GRE TUNNEL VPN IPv6-over-IPv4
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IPv6-over-IPv4手工隧道技术在智能电网中的应用 被引量:2
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作者 贾博 《电力信息与通信技术》 2014年第7期21-26,共6页
随着智能电网的快速发展,电力信息网迎来了发展的新机遇和新挑战。智能电网的建设需要有足够的IP地址作为支撑,在全网IPv4地址越来越匮乏的情况下,有巨大地址空间的IPv6将在智能电网未来的发展中显示出强大的优势。文章通过比较、分析IP... 随着智能电网的快速发展,电力信息网迎来了发展的新机遇和新挑战。智能电网的建设需要有足够的IP地址作为支撑,在全网IPv4地址越来越匮乏的情况下,有巨大地址空间的IPv6将在智能电网未来的发展中显示出强大的优势。文章通过比较、分析IPv6-over-IPv4隧道技术的应用场合、优缺点及需要具备的条件,在不改变现有网架结构的条件下,通过采用IPv6-over-IPv4手工隧道技术实现了站端IPv6视频设备平滑地接入企业级统一视频监控平台,可以为变电站的无人值守、输电线路的远程巡视及营业场所的服务监控等提供重要支撑。 展开更多
关键词 IPv6-over-IPv4 手工隧道 视频监控 智能电网
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基于Over-Issued CRL机制证书状态信息分发方法研究
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作者 刘小红 蒋兴浩 +1 位作者 汤劲松 陈抗生 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2002年第2期224-227,共4页
商用 CA或 PKI系统中主要使用定期颁布证书撤消列表 (CRL )来分发证书状态信息 ,但现有方法主要侧重于对 CRL的时间和空间特性改进 ,而对存储库性能的优化 ,尤其是如何有效降低存储库峰值负荷方面仍有一些未解决的问题 .本文通过对现有... 商用 CA或 PKI系统中主要使用定期颁布证书撤消列表 (CRL )来分发证书状态信息 ,但现有方法主要侧重于对 CRL的时间和空间特性改进 ,而对存储库性能的优化 ,尤其是如何有效降低存储库峰值负荷方面仍有一些未解决的问题 .本文通过对现有方法在存储库性能改进不力的分析 ,提出一个新的基于 Over- Issued CRL机制的证书状态信息分发方法 .它通过改变 Over- Issue发放的时间间隔 ,使得 CRL请求率大幅降低并迅速达到稳态 。 展开更多
关键词 证书撤消列表 公钥基础设施 峰值负荷 over-Issued CRL机制 证书状态信息分发 存储库 网络安全 PKI系统
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Study on Over-urbanization of the Ecotone between Mount Tai and Tai'an City
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作者 赵敬民 刘肖梅 乔晓红 《Journal of Landscape Research》 2010年第11期91-94,99,共5页
By investigating the ecotone between Mount Tai Scenic Area and downtown area of Tai'an City,the characteristics of such an ecotone are analyzed,serious problems brought by the over-urbanization to local natural en... By investigating the ecotone between Mount Tai Scenic Area and downtown area of Tai'an City,the characteristics of such an ecotone are analyzed,serious problems brought by the over-urbanization to local natural environment,such as destruction of eco-environment,aggravated pollution and degradation of mountainous landscape resources are studied.Then countermeasures for the harmonious development of the ecotone are proposed to better promote the coordinated development of cities and mountainous scenic areas. 展开更多
关键词 ECOTONE BETWEEN MOUNTAIN and CITY over-urbanization Problem MOUNT TAI
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IPv6-over-IPv4隧道技术在校园网中的实现 被引量:1
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作者 李清平 《现代计算机》 2009年第10期118-120,共3页
采用手动配置IPv6-over-IPv4隧道方法,通过一个具体的IPv6/IPv4共存校园网络的部署,以及路由器的端口设置、IP地址分配和各路由器的配置,实现基于隧道原理的IPv6穿越IPv4的透明传输,为IPv4过渡到IPv6提供了一种技术手段。
关键词 IPv6-over-IPv4 隧道技术 校园网 静态路由配置
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微细电铸Over-plating成型过程的数值模拟与实验研究 被引量:3
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作者 翟中平 王翔 孙浩 《现代制造工程》 CSCD 北大核心 2012年第8期21-25,共5页
微细电铸的Over-plating过程对电铸成型金属器件的质量有直接影响。通过有限元方法对微细电铸过程的电场进行建模分析,利用迭代边界法对Over-plating动态过程的阴极电流密度分布进行数值模拟;通过对直径300μm、深100μm微孔结构的电... 微细电铸的Over-plating过程对电铸成型金属器件的质量有直接影响。通过有限元方法对微细电铸过程的电场进行建模分析,利用迭代边界法对Over-plating动态过程的阴极电流密度分布进行数值模拟;通过对直径300μm、深100μm微孔结构的电铸实验,得到了不同时间下Over-plating过程的电铸层形貌;实验结果与数值模拟有着很好的一致性,表明基于有限元的迭代边界分析方法是合理的,也为后续对微细电铸Over-plating成型过程的定量分析提供了参考。 展开更多
关键词 微细电铸 over-plating成型过程 电流密度分布 有限元法 数值模拟
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低维快速DNS-over-HTTPS隧道流量检测方法
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作者 王涛 翟江涛 +2 位作者 王子豪 张凯杰 刘光杰 《网络空间安全科学学报》 2024年第6期123-130,共8页
安全DNS协议DNS-over-HTTPS(DoH)的标准化和部署应用,使DoH隧道成为一种新的隐蔽性网络威胁并受到广泛关注。在云网络环境中对大规模DoH业务流量中潜在的隧道流量进行甄别,需要同时兼顾计算效率和准确率。针对当前基于机器学习的DoH隧... 安全DNS协议DNS-over-HTTPS(DoH)的标准化和部署应用,使DoH隧道成为一种新的隐蔽性网络威胁并受到广泛关注。在云网络环境中对大规模DoH业务流量中潜在的隧道流量进行甄别,需要同时兼顾计算效率和准确率。针对当前基于机器学习的DoH隧道检测算法特征效率低、计算复杂度高的问题,设计了一组数据包块长度特征并提出了一种基于最大相关最小冗余(max-Relevance and Min-Re-dundancy,mRMR)特征筛选算法和随机森林算法的低维快速DoH隧道检测方法,该方法通过特征筛选选取对DoH隧道检测任务贡献大的特征,并使用随机森林分类器进行DoH隧道检测任务。实验结果表明,该方法在仅使用10维特征的情况下,达到了与使用24~34维特征的其他算法相当的准确率,可有效降低部署应用的计算复杂度,更好地适应大规模DoH业务流量分析的应用场景。 展开更多
关键词 DNS-over-HTTPS 隧道流量 mRMR算法 随机森林
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One hundred and one over-the-scope-clip applications forsevere gastrointestinal bleeding,leaks and fistulas 被引量:28
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作者 Edris Wedi Susana Gonzalez +3 位作者 Detlev Menke Elena Kruse Kai Matthes Juergen Hochberger 《World Journal of Gastroenterology》 SCIE CAS 2016年第5期1844-1853,共10页
AIM: To investigate the efficacy and clinical outcome of patients treated with an over-the-scope-clip(OTSC) system for severe gastrointestinal hemorrhage, perforations and fistulas.METHODS: From 02-2009 to 10-2012, 84... AIM: To investigate the efficacy and clinical outcome of patients treated with an over-the-scope-clip(OTSC) system for severe gastrointestinal hemorrhage, perforations and fistulas.METHODS: From 02-2009 to 10-2012, 84 patients were treated with 101 OTSC clips. 41 patients(48.8%) presented with severe upper-gastrointestinal(GI) bleeding, 3(3.6%) patients with lower-GI bleeding, 7 patients(8.3%) underwent perforation closure, 18 patients(21.4%) had prevention of secondary perforation, 12 patients(14.3%) had control of secondary bleeding after endoscopic mucosal resection or endoscopic submucosal dissection(ESD) and 3 patients(3.6%) had an intervention on a chronic fistula. RESULTS: In 78/84 patients(92.8%), primary treatment with the OTSC was technically successful. Clinical primary success was achieved in 75/84 patients(89.28%). The overall mortality in the study patients was 11/84(13.1%) and was seen in patients with life threatning upper GI hemorrhage. There was no mortality in any other treatment group. In detail OTSC application lead to a clinical success in 35/41(85.36%) patients with upper GI bleeding and in 3/3 patients with lower GI bleeding. Technical success of perforation closure was 100% while clinical success was seen in 4/7 cases(57.14%) due to attendant circumstances unrelated to the OTSC. Technical and clinic success was achieved in 18/18(100%) patients for the prevention of bleeding or perforation after endoscopic mucosal resection and ESD and in 3/3 cases of fistula closure. Two application-related complications were seen(2%).CONCLUSION: This largest single center experience published so far confirms the value of the OTSC for GI emergencies and complications. Further clinical experience will help to identify optimal indications for its targeted and prophylactic use. 展开更多
关键词 over-the-scope-clip Endoscopic therapy Gastrointestinal bleeding Perforation Fistula
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Nitrate Leaching from Maize Intercropping Systems with N Fertilizer Over-Dose 被引量:26
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作者 NIE Sheng-wei AEgfinya Eneji +3 位作者 CHEN Yuan-quan SUI Peng HUANG Jian-xiong HUANGShao-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第9期1555-1565,共11页
A 2-yr field experiment was conducted on a calcareous alluvial soil with four summer maize intercropping systems at Shangzhuang Experiment Station (116.3°E, 39.9°N) in the North China Plain. The objective ... A 2-yr field experiment was conducted on a calcareous alluvial soil with four summer maize intercropping systems at Shangzhuang Experiment Station (116.3°E, 39.9°N) in the North China Plain. The objective was to determine nitrate leaching from intercropping systems involving maize (Zea mays L.): sole maize (CK), maize + soybean (CST), maize + groundnut (CGT), maize + ryegrass (CHM), and maize + alfalfa (CMX). Intercropping greatly reduced nitrate accumulation in the 100-200 cm soil layers compared with maize monoculture. Nitrate accumulation under intercropping systems decreased significantly at the 140-200 cm soil depth; the accumulation varied in the order CK〉CST〉CMX〉CHM〉CGT. However, compared to the CK treatment, nitrate leaching losses during the maize growing period were reduced by 20.9- 174.8 (CGT), 35.2-130.8 (CHM), 60.4-122.0 (CMX), and 30.6-82.4 kg ha-1 (CST). The results also suggested that intereropping is an effective way to reduce nitrogen leaching in fields with N fertilizer over-dose. 展开更多
关键词 NO3-N leaching MAIZE INTERCROPPING over-dose
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Multipurpose use of the over-the-scope-clip system(“Bear claw”) in the gastrointestinal tract:Swiss experience in a tertiary center 被引量:17
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作者 Michael Christian Sulz Reto Bertolini +3 位作者 Remus Frei Gian-Marco Semadeni Jan Borovicka Christa Meyenberger 《World Journal of Gastroenterology》 SCIE CAS 2014年第43期16287-16292,共6页
AIM:To evaluate the outcome of over-the-scope-clip system(OTSC)for endoscopic treatment of various indications in daily clinical practice in Switzerland.METHODS:This prospective,consecutive case series was conducted a... AIM:To evaluate the outcome of over-the-scope-clip system(OTSC)for endoscopic treatment of various indications in daily clinical practice in Switzerland.METHODS:This prospective,consecutive case series was conducted at a tertiary care hospital from September 2010 to January 2014.Indications for OTSC application were fistulae,anastomotic leakage,perforation,unroofed submucosal lesion for biopsy,refractory bleeding,and stent fixation in the gastrointestinal(GI)tract.Primary technical success was defined as the adequate deployment of the OTSC on the target lesion.Clinical success was defined as resolution of the problem;for instance,no requirement for surgery or further endoscopic intervention.In cases of recurrence,retreatment of a lesion with a second intervention was possible.Complications were classified into those related to sedation,endoscopy,or deployment of the clip.RESULTS:A total of 28 OTSC system applications werecarried out in 21 patients[median age 64 years(range42-85),33%females].The main indications were fistulae(52%),mostly after percutaneous endoscopic gastrostomy tube removal,and anastomotic leakage after GI surgery(29%).Further indications were unroofed submucosal lesions after biopsy,upper gastrointestinal bleeding,or esophageal stent fixation.The OTSC treatments were applied either in the upper(48%)or lower(52%)GI tract.The mean lesion size was 8 mm(range:2-20 mm).Primary technical success and clinical success rates were 85%and 67%,respectively.In53%of cases,the suction method was used without accessories(e.g.,twin grasper or tissue anchor).No endoscopy-related or OTSC-related complications were observed.CONCLUSION:OTSC is a useful tool for endoscopic closure of various GI lesions,including fistulae and leakages.Future randomized prospective multicenter trials are warranted. 展开更多
关键词 over-the-scope-clip system OTSC Bear claw Endoscopic closure Gastrointestinal lesion Perforations FISTULAE Leakage
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Efficacy and safety of over-the-scope clip: Including complications after endoscopic submucosal dissection 被引量:43
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作者 Noriko Nishiyama Hirohito Mori +5 位作者 Hideki Kobara Kazi Rafiq Shintarou Fujihara Mitsuyoshi Kobayashi Makoto Oryu Tsutomu Masaki 《World Journal of Gastroenterology》 SCIE CAS 2013年第18期2752-2760,共9页
AIM: To retrospectively review the results of over-thescope clip (OTSC) use in our hospital and to examine the feasibility of using the OTSC to treat perforations after endoscopic submucosal dissection (ESD). METHODS:... AIM: To retrospectively review the results of over-thescope clip (OTSC) use in our hospital and to examine the feasibility of using the OTSC to treat perforations after endoscopic submucosal dissection (ESD). METHODS: We enrolled 23 patients who presented with gastrointestinal (GI) bleeding, fistulae and perforations and were treated with OTSCs (Ovesco Endoscopy GmbH, Tuebingen, Germany) between November 2011 and September 2012. Maximum lesion size was defined as lesion diameter. The number of OTSCs to be used per patient was not decided until the lesion was completely closed. We used a twin grasper (Ovesco Endoscopy GmbH, Tuebingen, Germany) as a grasping device for all the patients. A 9 mm OTSC was chosen for use in the esophagus and colon, and a 10 mm device was used for the stomach, duodenum and rectum. The overall success rate and complications were evaluated, with a particular emphasis on patients who had undergone ESD due to adenocarcinoma. In technical successful cases we included not only complete closing by using OTSCs, but also partial closing where complete closure with OTSCs is almost difficult. In overall clinical successful cases we included only complete closing by using only OTSCs perfectly. All the OTSCs were placed by 2 experienced endoscopists. The sites closed after ESD included not only the perforation site but also all defective ulcers sites.RESULTS: A total of 23 patients [mean age 77 years (range 64-98 years)] underwent OTSC placement during the study period. The indications for OTSC placement were GI bleeding (n = 9), perforation (n = 10), fistula (n = 4) and the prevention of post-ESD duodenal artificial ulcer perforation (n = 1). One patient had a perforation caused by a glycerin enema, after which a fistula formed. Lesion closure using the OTSC alone was successful in 19 out of 23 patients, and overall success rate was 82.6%. A large lesion size (greater than 20 mm) and a delayed diagnosis (more than 1 wk) were the major contributing factors for the overall unsuccessful clinical cases. The location of the unsuccessful lesion was in the stomach. The median operation time in the successful cases was 18 min, and the average observation time was 67 d. During the observation period, none of the patients experienced any complications associated with OTSC placement. In addition, we successfully used the OTSC to close the perforation site after ESD in 6 patients. This was a single-center, retrospective study with a small sample size. CONCLUSION: The OTSC is effective for treating GI bleeding, fistulae as well as perforations, and the OTSC technique proofed effective treatment for perforation after ESD. 展开更多
关键词 over-the-scope CLIP GASTROINTESTINAL bleed-ing Endoscopic submucosal dissection COMPLICATIONS GASTROINTESTINAL FISTULAE GASTROINTESTINAL perforation
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Over-plating工艺过程的变网格数值模拟(英文) 被引量:1
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作者 朱学林 王翔 褚家如 《光学精密工程》 EI CAS CSCD 北大核心 2009年第6期1293-1299,共7页
考察了over-plating工艺中不同线距、线宽条件下的电沉积规律。利用数值模拟方法对图形结构轮廓和电沉积速度之间的相互影响进行了分析,同时采用变网格方法来适应电沉积过程中结构轮廓的不断变化。数值模拟结果表明:当线距/线宽较大( &g... 考察了over-plating工艺中不同线距、线宽条件下的电沉积规律。利用数值模拟方法对图形结构轮廓和电沉积速度之间的相互影响进行了分析,同时采用变网格方法来适应电沉积过程中结构轮廓的不断变化。数值模拟结果表明:当线距/线宽较大( >12)时,相邻图形的电沉积速度受到的影响很小,图形的横向和纵向的电沉积速度逐渐趋于一致;而当线距/线宽较小( <6)时,相邻电沉积图形之间相互影响显著,线距/线宽越小,纵向电沉积速度和横向电沉积速度之比越大,因此相邻电沉积图形中间区域可能产生空洞,从而出现电镀缺陷的情形。对于上述工艺缺陷,可以通过增加辅助导电层进行消除,实验结果表明效果良好。 展开更多
关键词 over—plating UV—LIGA 变网格 模具
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Endoscopic closure of a gastrocolic fistula using the over-the-scope-clip-system 被引量:5
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作者 Klaus Mnkemüller Shajan Peter +3 位作者 Basem Alkurdi Jayapal Ramesh Daniel Popa C Mel Wilcox 《World Journal of Gastrointestinal Endoscopy》 CAS 2013年第8期402-406,共5页
Gastrointestinal (GI) defects such as fistulas and leaks can be potentially closed endoscopically using hemo-clips and loops. However, hemoclips may not allow for closure of large defects and they do not exert enough ... Gastrointestinal (GI) defects such as fistulas and leaks can be potentially closed endoscopically using hemo-clips and loops. However, hemoclips may not allow for closure of large defects and they do not exert enough tensile force to keep fibrotic defects larger than 5 mm approximated. Herein we present a case of successful endoscopic closure of a gastrocolic fistula in a severely malnourished patient with complex post-surgical upper GI anatomy. We strongly believe that this device is a major breakthrough for the management of various types of discontinuity defects or fistulas. In addition, we show the usefulness of placing a direct jejunostomy using the double balloon enteroscopy (DBE) technique during the same procedure. The concept of providing direct jejunal feedings while allowing for upper gas-trointestinal bowel rest to promote the healing of the minimally invasive endoscopic operation is novel. Thus, our case is unique and exemplifies the utility of mini-mally invasive endoscopic endoluminal surgery. 展开更多
关键词 over-the-scope-clip Bear claw FISTULA ENDOSCOPIC CLOSURE Gastrocolic FISTULA OVER the SCOPE CLIP CLIP
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Over-the-scope-clipping system for anastomotic leak after colorectal surgery:Report of two cases 被引量:4
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作者 Hirotoshi Kobayashi Akifumi Kikuchi +5 位作者 Satoshi Okazaki Megumi Ishiguro Toshiaki Ishikawa Satoru Iida Hiroyuki Uetake Kenichi Sugihara 《World Journal of Gastroenterology》 SCIE CAS 2014年第24期7984-7987,共4页
An anastomotic leak is one of the major complications following colorectal surgery.Standard treatments for anastomotic leak are total parenteral nutrition or temporary ileostomy.The over-the-scope-clipping(OTSC)system... An anastomotic leak is one of the major complications following colorectal surgery.Standard treatments for anastomotic leak are total parenteral nutrition or temporary ileostomy.The over-the-scope-clipping(OTSC)system was originally developed to treat intestinal perforation or to close the tissue after natural orifice transluminal endoscopic surgery.Two cases of successful management of an anastomotic leak after colorectal surgery using the OTSC system are reported.One patient avoided a temporary ileostomy.In the other,hospitalization was shortened by the use of the OTSC system.The OTSC system can be a potential option in the management of anastomotic leaks after colorectal surgery. 展开更多
关键词 over-the-scope-clipping Colorectal cancer Anastomotic leak Colorectal surgery Double stapling technique
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Dynamic Performance Evaluation of a Redundantly Actuated and Over-constrained Parallel Manipulator 被引量:5
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作者 Hai-Qiang Zhang Hai-Rong Fang +1 位作者 Bing-Shan Jiang Shuai-Guo Wang 《International Journal of Automation and computing》 EI CSCD 2019年第3期274-285,共12页
This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of freedom.The kinematics analysis is firstly carried out and... This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of freedom.The kinematics analysis is firstly carried out and the mapping relationship of the velocity,acceleration and the independent parameters between the actuator joint and the moving platform are deduced by using the vector dot product and cross product operation.By employing d′Alembert′s principle and the principle of virtual work,the dynamics equilibrium equation is derived,and the simplified dynamics mathematical model of the parallel manipulator is further derived.Simultaneously,the generalized inertia matrix which can characterize the acceleration performance between joint space and operation space is further separated,and the performance indices including the dynamics dexterity,inertia coupling characteristics,energy transmission efficiency and driving force/torque balance are introduced.The analysis results show that the proposed redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator in comparison with the existing non-redundant one has better dynamic comprehensive performance,which can be demonstrated practically by the successful application of the parallel kinematic machine head module of the hybrid machine tool. 展开更多
关键词 Redundantly actuated over-constrained PARALLEL MANIPULATOR dynamics performance INDEX
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Successful treatment of life-threatening bleeding from a duodenal posterior bulb peptic ulcer by an over-the-scope-clip 被引量:4
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作者 Thorsten Brechmann Wolff Schmiegel 《World Journal of Gastroenterology》 SCIE CAS 2015年第5期1666-1669,共4页
Bleeding of peptic ulcer at the posterior duodenal bulb still is a particular endoscopic challenge with increased risk of treatment failure and worse outcome.In this article,we report successful treatment of an active... Bleeding of peptic ulcer at the posterior duodenal bulb still is a particular endoscopic challenge with increased risk of treatment failure and worse outcome.In this article,we report successful treatment of an actively bleeding peptic ulcer located at the posterior duodenal wall,using an over-the-scope-clip in the case of a 54-year-old male patient with hemorrhagic shock.Incident primary hemostasis was achieved and no adverse events occurred during a follow-up of 60 d. 展开更多
关键词 over-the-scope-clip DUODENAL ULCER Upper gastroint
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EFFECT OF MELT OVER-HEATING AND ZIRCONIUM ALLOYING ON THE MORPHOLOGY OF Al_9FeNi PHASE AND MECHANICAL PROPERTIES OF 2618 ALLOY 被引量:6
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作者 J.H. WangMechanical Engineering Institute of Xiangtan University, Xiangtan 411105, ChinaD.Q. YiDepartment of Materials Science and Technology of Central South University, Changsha 410083, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第6期525-530,共6页
The effect of melt over-heating on the morphology of Al_9FeNi phase in 2618aluminum alloy with high contents of Fe and Ni and 0.22 wt. percent zirconium has been investigatedby optical microscopy. SEM and TEM. The mec... The effect of melt over-heating on the morphology of Al_9FeNi phase in 2618aluminum alloy with high contents of Fe and Ni and 0.22 wt. percent zirconium has been investigatedby optical microscopy. SEM and TEM. The mechanical properties of 2618 aluminum alloy after hotextrusion and quenching/aging have been tested. The results show: melt over-heating treatment of2618 alloy with high contents of Fe and Ni at 960 deg C led to finer and better-distributedneedle-like Al_9FeNi phase in cast microstructure and fine Al_9FeNi particles after hot extrusion;the grain size of the alloy after hot extrusion could also be refined evidently by alloying ofzirconium; the ambient and high temperature tensile strength and elongation of 2618 alloy have beenapparently enhanced due to fine Al_9FeNi particles and dispersed Al_3Zr as well as fine grain size. 展开更多
关键词 melt over-heating 2618 alloy zirconium alloying morphology of Al_9FeNiphase mechanical property
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