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101.
针对钻孔咬合桩围护结构在施工中需钻掉部分素混凝土,造成材料多耗且为施工带来不便的缺点,介绍了锁口管法,通过钻孔咬合桩的施工计划,施工方案以及锁口管设计,钻机选择,施工工艺,施工中的注意事项几方面论述了锁口管法可以避免以上缺点,证明应用此法可快速,优质地完成钻孔咬合桩墙围护结构。 相似文献
102.
Axel Haarmann Lena Zimmermann Michael Bieber Christine Silwedel Guido Stoll Michael K. Schuhmann 《International journal of molecular sciences》2022,23(13)
In large vessel occlusion stroke, recanalization to restore cerebral perfusion is essential but not necessarily sufficient for a favorable outcome. Paradoxically, in some patients, reperfusion carries the risk of increased tissue damage and cerebral hemorrhage. Experimental and clinical data suggest that endothelial cells, representing the interface for detrimental platelet and leukocyte responses, likely play a crucial role in the phenomenon referred to as ischemia/reperfusion (I/R)-injury, but the mechanisms are unknown. We aimed to determine the role of endoglin in cerebral I/R-injury; endoglin is a membrane-bound protein abundantly expressed by endothelial cells that has previously been shown to be involved in the maintenance of vascular homeostasis. We investigated the expression of membranous endoglin (using Western blotting and RT-PCR) and the generation of soluble endoglin (using an enzyme-linked immunosorbent assay of cell culture supernatants) after hypoxia and subsequent reoxygenation in human non-immortalized brain endothelial cells. To validate these in vitro data, we additionally examined endoglin expression in an intraluminal monofilament model of permanent and transient middle cerebral artery occlusion in mice. Subsequently, the effects of recombinant human soluble endoglin were assessed by label-free impedance-based measurement of endothelial monolayer integrity (using the xCELLigence DP system) and immunocytochemistry. Endoglin expression is highly inducible by hypoxia in human brain endothelial monolayers in vitro, and subsequent reoxygenation induced its shedding. These findings were corroborated in mice during MCAO; an upregulation of endoglin was displayed in the infarcted hemispheres under occlusion, whereas endoglin expression was significantly diminished after transient MCAO, which is indicative of shedding. Of note is the finding that soluble endoglin induced an inflammatory phenotype in endothelial monolayers. The treatment of HBMEC with endoglin resulted in a decrease in transendothelial resistance and the downregulation of VE-cadherin. Our data establish a novel mechanism in which hypoxia triggers the initial endothelial upregulation of endoglin and subsequent reoxygenation triggers its release as a vasoactive mediator that, when rinsed into adjacent vascular beds after recanalization, can contribute to cerebral reperfusion injury. 相似文献
103.
系统振荡又发生短路故障时距离保护的动作行为分析 总被引:6,自引:0,他引:6
对几种常见的距离保护振荡闭锁原理进行简要分析,指出各种原理的优缺点,并提出今后努力的方向。 相似文献
104.
Chu-Yin Chang Anthony A. Maciejewski Venkataramanan Balakrishnan Rodney G. Roberts Kishor Saitwal 《Pattern Analysis & Applications》2007,10(1):15-31
Eigendecomposition-based techniques are popular for a number of computer vision problems, e.g., object and pose estimation,
because they are purely appearance based and they require few on-line computations. Unfortunately, they also typically require
an unobstructed view of the object whose pose is being detected. The presence of occlusion and background clutter precludes
the use of the normalizations that are typically applied and significantly alters the appearance of the object under detection.
This work presents an algorithm that is based on applying eigendecomposition to a quadtree representation of the image dataset
used to describe the appearance of an object. This allows decisions concerning the pose of an object to be based on only those
portions of the image in which the algorithm has determined that the object is not occluded. The accuracy and computational
efficiency of the proposed approach is evaluated on 16 different objects with up to 50% of the object being occluded and on
images of ships in a dockyard.
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献
Anthony A. MaciejewskiEmail: |
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献
105.
在增强现实系统的复杂场景中,对目标的实时跟踪受到场景中诸多因素的制约,导致实时跟踪方法效率低且不准确,为此提出一种基于自然特征的实时跟踪方法。设计了一种螺旋分割模型,对捕获的图像进行螺旋分割,利用SURF算法在分割子块中提取特征点,并进行匹配。在对目标进行跟踪定位时,利用前一帧来预测当前帧目标出现的位置,以减少SURF算法的扫描区域,加速系统运算效率。实验中分别对场景光线强弱、视点和仿射变化以及目标被部分遮挡等不同情况进行测试,该方法均表现出较高的跟踪效率。 相似文献
106.
Deokho Lee Yohei Tomita Yukihiro Miwa Heonuk Jeong Ari Shinojima Norimitsu Ban Shintaro Yamaguchi Ken Nishioka Kazuno Negishi Jun Yoshino Toshihide Kurihara 《International journal of molecular sciences》2022,23(23)
Cardiovascular abnormality-mediated retinal ischemia causes severe visual impairment. Retinal ischemia is involved in enormous pathological processes including oxidative stress, reactive gliosis, and retinal functional deficits. Thus, maintaining retinal function by modulating those pathological processes may prevent or protect against vision loss. Over the decades, nicotinamide mononucleotide (NMN), a crucial nicotinamide adenine dinucleotide (NAD+) intermediate, has been nominated as a promising therapeutic target in retinal diseases. Nonetheless, a protective effect of NMN has not been examined in cardiovascular diseases-induced retinal ischemia. In our study, we aimed to investigate its promising effect of NMN in the ischemic retina of a murine model of carotid artery occlusion. After surgical unilateral common carotid artery occlusion (UCCAO) in adult male C57BL/6 mice, NMN (500 mg/kg/day) was intraperitoneally injected to mice every day until the end of experiments. Electroretinography and biomolecular assays were utilized to measure ocular functional and further molecular alterations in the retina. We found that UCCAO-induced retinal dysfunction was suppressed, pathological gliosis was reduced, retinal NAD+ levels were preserved, and the expression of an antioxidant molecule (nuclear factor erythroid-2-related factor 2; Nrf2) was upregulated by consecutive administration of NMN. Our present outcomes first suggest a promising NMN therapy for the suppression of cardiovascular diseases-mediated retinal ischemic dysfunction. 相似文献
107.
在复杂背景下,光照变化、目标短暂遮挡以及背景运动等因素会导致运动目标检测精度较低.提出一种结合改进混合高斯模型和改进五帧差分的运动目标检测算法,首先在混合高斯模型中加入自适应学习率以及背景学习速率更新策略有效解决传统背景更新速率恒定而出现的残影现象;然后利用改进的五帧差分法克服运动目标短暂遮挡问题,并加入光照阈值判别因... 相似文献
108.
109.
申杰 《计算机工程与科学》2008,30(1):45-48
本文使用张量的方法推导了基于仿射空间的免标定增强现实方法,该方法不需要像机的标定参数和环境对象的3D位置信息就可实现视频增强。同时,本文也提出了在仿射空间解决增强现实中遮挡问题的新方法,给出了基于免标定增强现实的视频增强主要想法和应用实例。结果表明,这个方法是可行的。 相似文献
110.