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Predictive Value of Resting Pd/Pa for Fractional Flow Reserve Assessed with Monorail Pressure Microcatheter in Real-World Practice

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Cardiovascular Innovations and Applications 2019年第B07期4卷 113-120页

作者： Keng Tat Koh Asri Said Khaw Chee Sin Oon Yen Yee Erwin Mulia Tan Chen Ting Francis Shu eng Pbeng Ho Kian hui Voon Chi Yen Cham Yee Ling Khiew Ning Zan Nor Hanim Mohd Amin Alan Fong Yean Yip ong Tiong Kiam Department of Cardiology Sarawak Heart Centre3rd RoundaboutSamarahan Expressway94300 Kota SamarahanSarawakMalaysia Faculty of Medicine and Health Sciences University Malaysia Sarawak94300 Kota SamarahanSarawakMalaysia Clinical Research Centre Sarawak General HospitalJalan Hospital 93586 KuchingSarawakMalaysia

Background and Objectives:The aims of this study were(1)to examine the diagnostic accuracy of resting timeaveraged distal coronary pressure(Pd)to mean aortic pressure(Pa)ratio to predict hyperemic fractional flow reserve(FFR)and(2)to identify a resting Pd/Pa value that can preclude the need for hyperemic FFR assessed with use of a monorail pressure ***:A total of 191 stenoses were *** exclusions,157 FFR data sets from 103 patients were ***:Resting Pd/Pa showed poor agreement with hyperemic FFR(r=0.619,P<0.001).The receiver operating characteristic curve for resting Pd/Pa with reference to hyperemic FFR of 0.80 or less showed an area under the curve of 0.800(95%confi dence interval 0.732– 0.868,P<0.001),with the greatest diagnostic accuracy of 74.5%for resting Pd/Pa of less than *** Pd/Pa of 0.96 or greater had a sensitivity of 100%and a negative predictive value of 100%,and resting Pd/Pa of 0.82 or less had a specifi city of 98.9%and a positive predictive value of 94.1%to predict abnormal FFR of 0.80 or *** results were consistent regardless of the vessels studied,the location of lesions,and the severity of ***:Resting Pd/Pa showed poor agreement with hyperemic FFR assessed with use of a monorail pressure ***,resting Pd/Pa of 0.96 or greater had excellent sensitivity and negative predictive value to predict normal hyperemic FFR,and resting Pd/Pa of 0.82 or less had excellent specifi city and positive predictive value to predict abnormal hyperemic FFR.

关键词： fractional fl ow reserve monorail pressure catheter resting time-averaged distal coronary pressure to mean aortic pressure ratio

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黑色谷物昆虫导致的严重眼部创伤1例(英文)

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国际眼科杂志 2010年第7期10卷 1253-1256页

作者： eng-hui Gan Kel-Vin Chin Syed Shoeb Ahmad Shuaibah Abdut Ghani Wan Hazabbah Wan Hitam 马来西亚吉兰丹市马来西亚理科大学医学院眼科马来西亚沙巴州哥打基纳巴卢伊丽莎白医院眼科

患者,女,农民,59岁,左眼被名为Scotinophara菌的黑色谷物昆虫蜇伤后疼痛肿胀1wk,表现为急性进行性视物模糊。左眼检查发现有明显的眼球突出、眶周肿胀和上睑下垂,眼球各个方向运动均受到限制。角膜浑浊伴上皮大片缺损。眼底检查发现视... 详细信息

患者,女,农民,59岁,左眼被名为Scotinophara菌的黑色谷物昆虫蜇伤后疼痛肿胀1wk,表现为急性进行性视物模糊。左眼检查发现有明显的眼球突出、眶周肿胀和上睑下垂,眼球各个方向运动均受到限制。角膜浑浊伴上皮大片缺损。眼底检查发现视网膜中央动、静脉闭塞,视盘水肿和黄斑区缺血等特征。CT扫描和脑与眼眶MRI检查发现眼眶软组织炎症。患者诊断为左眼眶蜂窝织炎、角膜炎(角膜葡萄肿)和和视网膜中央动静脉闭塞。全身和局部抗菌素治疗后,眼眶周围肿胀,眼球突出明显改善。但是视力仍为无光感,此外,仍存在持续性眼球运动障碍。Scotinophara菌产生了严重的和长久的潜在眼部刺激。Scotinophara菌所致可觉察的轻微人眼伤害尤其在易发部位应该及时给予滴眼液治疗。

关键词：眼损伤昆虫化学损伤眼眶蜂窝组织炎视网膜中央静脉阻塞视网膜中央动脉阻塞

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C_(6)F_(12)O混合气体与三元乙丙橡胶的相容性研究

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工程科学与技术 2024年第5期56卷 106-116页

作者：田双双刘本立邓广宇张晓星李慧慧刘伟豪陈辉湖北工业大学新能源及电网装备安全监测湖北省工程研究中心湖北武汉430068 襄阳湖北工业大学产业研究院湖北襄阳441000 国网湖北省电力有限公司经济技术研究院湖北武汉430000

C_(6)F_(12)O作为一种新型环保绝缘气体,与缓冲气体混合后具有作为绝缘介质运用于中低压电气设备的潜力。然而,环保气体绝缘设备内的密封材料是否与C_(6)F_(12)O长期兼容还有待深入研究。为此,本文研究了C_(6)F_(12)O/CO_(2)混合气体与... 详细信息

C_(6)F_(12)O作为一种新型环保绝缘气体,与缓冲气体混合后具有作为绝缘介质运用于中低压电气设备的潜力。然而,环保气体绝缘设备内的密封材料是否与C_(6)F_(12)O长期兼容还有待深入研究。为此,本文研究了C_(6)F_(12)O/CO_(2)混合气体与气体绝缘设备中常用的三元乙丙橡胶(EPDM)的相容性和O_(2)对C_(6)F_(12)O/CO_(2)混合气体与EPDM相容性的影响。本文搭建了气固相容性实验平台,并结合实际运行温度进行不同温度下C_(6)F_(12)O混合气体与EPDM的相容性实验,测试了实验后EPDM的表面形貌、表面元素、力学性能和气体成分的变化,以确定C_(6)F_(12)O混合气体与EP-DM的长期相容性。同时,构建了C_(6)F_(12)O混合气体与EPDM分子链的仿真模型,基于分子动力学(MD)理论计算了C_(6)F_(12)O、CO_(2)与EPDM之间的扩散系数、相互作用参数和混合能。结果表明:在110℃热加速实验后EPDM表面产生鳞状结构,并在EPDM表面检测到C—F键、有机氟化物和金属氟化物,EPDM的力学性能降低,实验后主要气体产物为C_(3)F_(6)和C_(3)F_(7)H。加入O_(2)后,EPDM在90℃时表面出现凸起,并且有大量O、F元素积累在表面,EPDM力学性能下降,气体产物增多。理论计算也表明升高温度和加入O_(2)会加速C_(6)F_(12)O混合气体在EPDM中的扩散,导致气体分子与EPDM相容性变差。本文的研究成果将为C_(6)F_(12)O气体绝缘设备的设计和制造过程提供参考。

关键词： C_(6)F_(12)O混合气体三元乙丙橡胶相容性分子动力学模拟

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AN MAC PROTOCOL SUPPORTING MULTIPLE TRAFFIC OVER MOBILE AD HOC NETWORKS

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Journal of Electronics(China) 2003年第2期20卷 116-120页

作者： Tian hui Li Yingyang Hu Jiandong Zhang Ping (College of Telecom. eng., Beijing University of Posts & Telecommunications, Beijing 100876) College of Telecom. eng. Beijing University of Posts & Telecommunications Beijing100876

This letter presents the design and performance of a multi-channel MAC protocol that supports multiple traffics for IEEE 802.11 mobile ad-hoc networks. The dynamic channel selection scheme by receiver decision is implemented and the number of the data channel is independent of the network topology. The priority for real-time traffic is assured by the proposed adaptive back off algorithm and different IFS. The protocol is evaluated by simulation and the results have shown that it can support multiple traffics and the performance is better than the performance that IEEE 802.11 standard provides.

关键词： Wireless networks Ad hoc wireless LAN Medium access control protocol

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Influence on Conductivity of Polyparaphenylene by Chemical Doping and Ion Implantation

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Semiconductor Photonics and Technology 1999年第2期5卷 114-118页

作者： WANG hui, WU Hong-cai (School of Electron. & Inform. eng., Xi’an Jiaotong University, Xi’an 710049,CHN)

Polyparaphenylene(PPP) is prepared by AlCl 3-CuCl 2 catalysts with benzene as the monomer and is doped by chemical method and N + ion implantation. The influences of the concentration, temperature and time of chemical doping and the dose, energy and temperature of ion implantation, on PPP conductivity are investigated. The results showed that the conductivity of PPP can be improved 4～5 orders of magnitude by ion implantation and the conductivity of PPP can reach about 0.11 S·cm -1 by chemical doping. The comparison of stability of the material conductive behavior by using the two doping methods is presented. It shows that ion implantation is better than chemical doping in stabilizing the electric conductive behavior for the material.

关键词： Conducting Polymers, Ion Implantation, Polyparaphenylene CLC number:O 631.23 O 632.7 TN304.52 Document code:A

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多晶Sr_2Fe_(1-x)Al_xMoO_6的晶粒内低场磁电阻效应

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物理学报 2005年第2期54卷 907-911页

作者：王先杰隋郁千正男程金光刘志国李妍苏文辉 C.K.ong 哈尔滨工业大学理学院凝聚态科学与技术研究中心哈尔滨150001 新加坡国立大学物理系超导与磁性材料研究中心新加坡117542

用传统的固相反应法合成了Fe位掺杂Al的双钙钛矿型氧化物Sr2 Fe1 -xAlxMoO6 (x =0 0 ,0 0 5 ,0 10 ,0 15 ,0 3)多晶材料 .x射线衍射和扫描电子显微分析显示 ,在Fe位掺杂Al既没有引入杂相 ,也没有明显改变Sr2 FeMoO6 多晶材料的晶... 详细信息

用传统的固相反应法合成了Fe位掺杂Al的双钙钛矿型氧化物Sr2 Fe1 -xAlxMoO6 (x =0 0 ,0 0 5 ,0 10 ,0 15 ,0 3)多晶材料 .x射线衍射和扫描电子显微分析显示 ,在Fe位掺杂Al既没有引入杂相 ,也没有明显改变Sr2 FeMoO6 多晶材料的晶粒尺寸和晶界状态 .非磁性Al离子的掺杂使晶粒内部磁有序区细化成更小的区域 ,同时使反铁磁区内的磁耦合作用变弱 .这一方面提高了亚铁磁区磁化方向的磁场灵敏度 ;另一方面也降低了反铁磁区对自旋相关电子的散射 ;两方面的共同作用使Sr2 FeMoO6 的低场磁电阻效应明显增强 ,但这种尺寸效应也使材料的磁电阻在高温下下降得更快 .

关键词：反铁磁磁电阻效应钙钛矿型氧化物自旋掺杂磁性离子低场改变作用

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An experimental investigation on the trailing edge cooling of turbine blades

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Propulsion and Power Research 2012年第1期1卷 36-47页

作者： Zifeng Yang hui Hun Department of Aerospace engineering Iowa State UniversityAmesIA 50011USA

An experimental study was conducted to quantify the flow characteristics of the wall jets pertinent to trailing edge cooling of turbine blades.A high-resolution stereoscopic particle image velocimetry(PIV)system was used to conduct detailed flow field measurements to quantitatively visualize the evolution of the unsteady vortices and turbulent flow structures in the cooling wall jet streams and to quantify the dynamic mixing process between the cooling jet stream and the mainstream *** detailed flow field measurements were correlated with the adiabatic cooling effectiveness maps measured by using pressure sensitive paint(PSP)technique to elucidate underlying physics in order to explore/optimize design paradigms for improved cooling effectiveness to protect the critical portions of turbine blades from harsh environments.

关键词： Trailing edge cooling Wall slot jets Turbine blades Steroscopic particle image velocimetry(PIV)measurements Pressure sensitive paint(PSP)technique

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基于相似匹配维纳滤波的地震资料噪声压制

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吉林大学学报（工学版） 2017年第6期47卷 1964-1968页

作者：李娟孟可心李月刘慧力吉林大学通信工程学院长春130012 吉林大学生物与农业工程学院长春130022

针对强噪声背景下地震资料噪声压制困难的问题,提出一种基于地震信号相似性的维纳滤波传递函数优化算法。该算法将待处理资料分块,并依据地震同相轴的时空相似性构建三维相似组。经过低秩近似,信号与噪声差异明显,能够计算得出更为精确... 详细信息

针对强噪声背景下地震资料噪声压制困难的问题,提出一种基于地震信号相似性的维纳滤波传递函数优化算法。该算法将待处理资料分块,并依据地震同相轴的时空相似性构建三维相似组。经过低秩近似,信号与噪声差异明显,能够计算得出更为精确的维纳滤波传递函数。经过仿真信号与真实地震资料的对比验证,采用本文优化算法得到的传递函数进行维纳滤波,既能实现随机噪声的有效压制,又能极大地保护信号的有效成分。

关键词：信息处理技术维纳滤波块匹配奇异值分解

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Parameter Test of ROIC for IRFPA Based on Virtual Instrument Technology

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Semiconductor Photonics and Technology 2001年第3期7卷 150-154,162页

作者： JIA Gong xian, YUAN Xiang hui, HUANG You shu, LU Guo lin (School of Photoelectric eng., Chongqing University, Chongqing 400044, CHN) 重庆大学光电工程学院重庆 400044

The readout integrated circuit (ROIC) technology is one of the critical technologies in the research of an infrared focal plane array (IRFPA). Based on the virtual instrument technology, a system for parameter test of ROIC is developed for IRFPA. The complex programmable logic device (CPLD) is applied into the system to increase its flexibility. With high reliability and precision, along with the integrated software and hardware environment, the system can test all kinds of ROICs.

关键词： Virtual instruments ROIC IRFPA CPLD

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Influence of random shrinkage porosity on equivalent elastic modulus of casting： A statistical and numerical approach

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China Foundry 2017年第2期14卷 108-120页

作者： Wei Liu Feng Li Fuhua Yan hui Wang School of Mechanics Civil Eng. & Architecture Northwestern Polytechnical University Xi'an 710129 China No.12 Research Institute of CSIC Xingping 713102 China

Shrinkage porosity is a type of random distribution defects and exists in most large castings. Different from the periodic symmetry defects or certain distribution defects, shrinkage porosity presents a random "cloud-like" configuration, which brings difficulties in quantifying the effective performance of defected casting. In this paper, the influences of random shrinkage porosity on the equivalent elastic modulus of QT400-18 casting were studied by a numerical statistics approach. An improved random algorithm was applied into the lattice model to simulate the "cloud-like" morphology of shrinkage porosity. Then, a large number of numerical samples containing random levels of shrinkage were generated by the proposed algorithm. The stress concentration factor and equivalent elastic modulus of these numerical samples were calculated. Based on a statistical approach, the effects of shrinkage porosity's distribution characteristics, such as area fraction, shape, and relative location on the casting's equivalent mechanical properties were discussed respectively. It is shown that the approach with randomly distributed defects has better predictive capabilities than traditional methods. The following conclusions can be drawn from the statistical simulations:(1) the effective modulus decreases remarkably if the shrinkage porosity percent is greater than 1.5%;(2) the average Stress Concentration Factor(SCF) produced by shrinkage porosity is about 2.0;(3) the defect's length across the loading direction plays a more important role in the effective modulus than the length along the loading direction;(4) the surface defect perpendicular to loading direction reduces the mean modulus about 1.5% more than a defect of other position.

关键词： random lattice model equivalent elastic modulus shrinkage porosity defects casting

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