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Coherence of Superposition States
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作者 宇文珊珊 邵连合 席政军 《理论物理通讯:英文版》 CSCD 2019年第9期1084-1088,共5页
We find tight upper bound on the coherence of a superposition of two states in terms of the coherence of the two states constituting the superposition with l1-norm of coherence. Our upper bound is tighter than the one... We find tight upper bound on the coherence of a superposition of two states in terms of the coherence of the two states constituting the superposition with l1-norm of coherence. Our upper bound is tighter than the one presented by Liu, et al. [Quantum Inf. Process. 15(2016) 4209.] We also generalize the results to the case that the superposition is constituted with more than two states in high dimension, and we give the corresponding upper bounds. 展开更多
关键词 QUANTUM COHERENCE SUPERPOSITION STATES l1-norm of COHERENCE
英语句子逻辑连贯能力与英语写作水平潜在关系研究
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作者 白丽茹 《外语研究》 CSSCI 北大核心 2019年第1期52-57,112共7页
本研究以220名大二年级英语学习者为被试实施系列实证研究,尝试探讨英语句子逻辑连贯能力与英语写作水平的潜在关系。研究结果表明:英语句子逻辑连贯能力/技能/亚技能与英语写作水平存在显著相关,但相关程度存在个体差异;英语句子逻辑... 本研究以220名大二年级英语学习者为被试实施系列实证研究,尝试探讨英语句子逻辑连贯能力与英语写作水平的潜在关系。研究结果表明:英语句子逻辑连贯能力/技能/亚技能与英语写作水平存在显著相关,但相关程度存在个体差异;英语句子逻辑连贯认知技能和应用技能联合为英语写作水平显著预测源,其中英语句子逻辑连贯认知技能对英语写作水平贡献率相对较大;英语句子逻辑连贯亚技能联合对英语写作水平具有显著预测作用,其中英语句子逻辑匹配亚技能和英语句子逻辑监控亚技能对英语写作水平贡献率基本一致,其次为英语句子逻辑连接亚技能和英语句子逻辑识别亚技能。 展开更多
关键词 连贯 英语句子逻辑连贯能力 英语写作水平 潜在关系
基于光电容积脉搏波信号与心电信号相关性的研究 预览
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作者 陈真诚 于邦文 +2 位作者 梁永波 曾若生 朱健铭 《生物医学工程研究》 2019年第3期370-375,共6页
在研究光电容积脉搏波信号(photoplethysmography,PPG)与心电信号(electrocardiography,ECG)相关性的基础上加入了动脉血压信号(arterial blood pressure,ABP)以及呼吸信号(resperation,RESP)。探究PPG信号与其余三路信号间的相关性以... 在研究光电容积脉搏波信号(photoplethysmography,PPG)与心电信号(electrocardiography,ECG)相关性的基础上加入了动脉血压信号(arterial blood pressure,ABP)以及呼吸信号(resperation,RESP)。探究PPG信号与其余三路信号间的相关性以及因果关系等统计学指标,并给出具体的统计学实验结果,为以后使用该类统计学指标做心血管以及呼吸类疾病筛查做准备。通过时域与频域相结合的办法求取相关性,在时域上利用Pearson相关系数,频域上利用相干性与短时偏定向相干性算法(ST-PDC)以及短时定向传递函数算法(ST-DTF)探究信号间的因果关系及连通性。时域上信号间的相关性系数均值分别为0.901、0.894、0.886,频域上信号间的相干性均值分别为0.899、0.896、0.8816,ST-PDC以及ST-DTF算法结果表明了信号之间存在较强的因果关系。时域与频域的实验结果表明信号间存在着较强的相关性。 展开更多
关键词 多路信号 时域 频域 相关性 相干性 偏定向相干性 定向传递函数
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Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study 预览
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作者 Osman OguzAhsen Kaicheng Liang +3 位作者 Hsiang-Chieh Lee Zhao Wang James G Fujimoto Hiroshi Mashimo 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第16期1997-2009,共13页
BACKGROUND Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is de... BACKGROUND Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of life. Radiofrequency ablation (RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease management. AIM To study feasibility of optical coherence tomography angiography (OCTA) for investigating subsurface vascular alterations in CRP and response to RFA treatment. METHODS Two patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahighspeed optical coherence tomography (OCT) system over 15 OCT/colonoscopy visits (2 normal patients, 5 RFA-na?ve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, without requiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic scoring. RESULTS OCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 μm in diameter versus abnormal heterogenous enlarged arterioles and ve 展开更多
关键词 OPTICAL COHERENCE TOMOGRAPHY OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY Radiofrequency ablation CHRONIC RADIATION proctopathy Rectal telangiectasia density scoring system Subsurface microvascular imaging
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Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients
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作者 Antonio Manuel Garrido-Hermosilla Mariola Méndez-Muros +6 位作者 Estanislao Gutiérrez-Sánchez Cristóbal Morales-Portillo María Jesús Díaz-GrANDa Eduardo Esteban-González Isabel Relimpio-López María Asunción Martínez-Brocca Enrique Rodríguez-de-la-Rúa-Franch 《国际眼科杂志:英文版》 SCIE CAS 2019年第6期985-989,共5页
AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Dem... AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients. 展开更多
关键词 choroidal thickness renal function swept-source OPTICAL COHERENCE TOMOGRAPHY SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY diabetes MELLITUS
Electrical activities of neural systems exposed to sinusoidal induced electric field with random phase
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作者 DU Lin CAO ZiLu +1 位作者 LEI YouMing DENG ZiChen 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第7期1141-1150,共10页
The brain neural system is often disturbed by electromagnetic and noise environments, and research on dynamic response of its interaction has received extensive attention. This paper investigates electrical activity o... The brain neural system is often disturbed by electromagnetic and noise environments, and research on dynamic response of its interaction has received extensive attention. This paper investigates electrical activity of Morris-Lecar neural systems exposed to sinusoidal induced electric field(IEF) with random phase generated by electromagnetic effect. By introducing a membrane depolarization model under the effect of random IEF, transition state of firing patterns, including mixed-mode oscillations(MMOs) with layered inter-spike intervals(ISI) and intermittency with a power law distribution in probability density function of ISI, is obtained in a single neuron. Considering the synergistic effects of frequency and noise, coherence resonance is performed by phase noise of IEF under certain parameter conditions. For the neural network without any internal coupling, we demonstrate that synchronous oscillations can be induced by IEF coupling, and suppression of synchronous spiking is achieved effectively by phase noise of IEF. Results of the study enrich the dynamical response to electromagnetic induction and provide insights into mechanisms of noise affecting information coding and transmission in neural systems. 展开更多
关键词 induced electric field random phase ELECTRICAL activity transition COHERENCE RESONANCE SYNCHRONOUS SUPPRESSION
叠后地震多属性分析在煤层裂缝识别中的应用 预览
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作者 仇念广 《能源与环保》 2019年第7期244-248,共5页
针对山西新元矿煤层中的裂缝发育问题,以地震属性分析理论为指导,研究了相干、曲率、蚂蚁体等单一地震属性、多属性叠合、多属性神经网络运算裂缝概率等在裂缝识别中的应用效果,地震属性的走向确定了裂缝的方位信息,多属性分析圈定了裂... 针对山西新元矿煤层中的裂缝发育问题,以地震属性分析理论为指导,研究了相干、曲率、蚂蚁体等单一地震属性、多属性叠合、多属性神经网络运算裂缝概率等在裂缝识别中的应用效果,地震属性的走向确定了裂缝的方位信息,多属性分析圈定了裂缝发育区域。结合邻区已采掘区域揭露的断裂发育情况,表明以相干、曲率和蚂蚁体等叠后多属性对于裂缝的应用识别效果较好。地震多属性分析对于煤层裂缝的识别有着较好的应用价值,可推广至其他煤矿应用。 展开更多
关键词 地震属性 裂缝 相干 曲率 蚂蚁体 新元矿
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The Strategies of College English Writing 预览
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作者 ZHANG Jie 《中美英语教学:英文版》 2019年第5期203-208,共6页
This paper is to restate the importance of English writing for the Chinese students. The paper will focus on the problems exist in the students writing, such as, the misunderstood topic, the lexical mistakes, the phra... This paper is to restate the importance of English writing for the Chinese students. The paper will focus on the problems exist in the students writing, such as, the misunderstood topic, the lexical mistakes, the phrase mistakes, and the coherence and unity errors. And the highlight of the paper is to deal with how to overcome the difficulties by emphasizing the elements, such as deciding on a genre of a composition, unity, and coherence for each paragraph and a whole text, the controlling idea in a paragraph and a composition and the logic realization in writing. Using proper and academic words is also necessary element in composing a text. 展开更多
关键词 TOPIC ACADEMIC WORDS the structure of SENTENCES and COHESION and COHERENCE
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主述位理论对商务英语信函写作连贯的启发 预览
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作者 闫玲玉 《吉林省教育学院学报》 2019年第6期92-95,共4页
本文参照韩礼德和赖清燕对主位的定义和分类,及朱永生和严世清对主位推进类型的分类,采用随机抽取、逐句标注的方式对不同质量等级商务英语信函中主位的选择、主位推进使用的特点进行了分析。分析表明:在商务英语信函写作中,作者更倾向... 本文参照韩礼德和赖清燕对主位的定义和分类,及朱永生和严世清对主位推进类型的分类,采用随机抽取、逐句标注的方式对不同质量等级商务英语信函中主位的选择、主位推进使用的特点进行了分析。分析表明:在商务英语信函写作中,作者更倾向于使用单项主位和复项主位,其次为句项主位;在主位推进类型的使用上,除交叉型没被使用外,述位同一型、延续型、主位同一型都有所使用,且使用频率较为均衡。此外,商务英语信函写作质量越高,单项主位的使用越少,复项主位和句项主位的使用越多;随着信函写作质量的提高,写作中的有效主位推进模式所占比例也有所上升,使得文章更加连贯。 展开更多
关键词 主位选择 主位推进 商务英语写作 连贯
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Automatic Calcified Plaques Detection in the OCT Pullbacks Using Convolutional Neural Networks
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作者 Chunliu He Yifan Yin +2 位作者 Jiaqiu Wang Biao Xu Zhiyong Li 《医用生物力学》 CAS CSCD 北大核心 2019年第A01期109-110,共2页
Background Coronary artery calcification is a well-known marker of atherosclerotic plaque burden.High-resolution intravascular optical coherence tomography(OCT)imaging has shown the potential to characterize the detai... Background Coronary artery calcification is a well-known marker of atherosclerotic plaque burden.High-resolution intravascular optical coherence tomography(OCT)imaging has shown the potential to characterize the details of coronary calcification in vivo.In routine clinical practice,it is a time-consuming and laborious task for clinicians to review the over 250 images in a single pullback.Besides,the imbalance label distribution within the entire pullbacks is another problem,which could lead to the failure of the classifier model.Given the success of deep learning methods with other imaging modalities,a thorough understanding of calcified plaque detection using Convolutional Neural Networks(CNNs)within pullbacks for future clinical decision was required.Methods All 33 IVOCT clinical pullbacks of 33 patients were taken from Affiliated Drum Tower Hospital,Nanjing University between December 2017 and December 2018.For ground-truth annotation,three trained experts determined the type of plaque that was present in a B-Scan.The experts assigned the labels'no calcified plaque','calcified plaque'for each OCT image.All experts were provided the all images for labeling.The final label was determined based on consensus between the experts,different opinions on the plaque type were resolved by asking the experts for a repetition of their evaluation.Before the implement of algorithm,all OCT images was resized to a resolution of 300×300,which matched the range used with standard architectures in the natural image domain.In the study,we randomly selected 26 pullbacks for training,the remaining data were testing.While,imbalance label distribution within entire pullbacks was great challenge for various CNNs architecture.In order to resolve the problem,we designed the following experiment.First,we fine-tuned twenty different CNNs architecture,including customize CNN architectures and pretrained CNN architectures.Considering the nature of OCT images,customize CNN architectures were designed that the layers were fewer than 25 layers 展开更多
关键词 CALCIFIED PLAQUE INTRAVASCULAR optical COHERENCE tomography deep learning IMBALANCE LABEL distribution convolutional neural networks
Optimizing woven coronary artery management by optical coherence tomography: three cases report 预览
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作者 Xi WANG Xiao-Qing CAI +11 位作者 Qi WANG Yang LIU Dong-Kai SHAN Lei WANG Shan-Shan ZHOU Jing JING Wei HU Kai WANG Zi-Nuan LIU Feng TIAN Jun GUO Yun-Dai CHEN 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第8期656-659,共4页
Woven coronary artery (WCA) is a rare and underdiagnosed anomaly characterized by epicardial coronary artery dividing into multiple twisted single channels then anastomosing at distal segment. The malformation is usua... Woven coronary artery (WCA) is a rare and underdiagnosed anomaly characterized by epicardial coronary artery dividing into multiple twisted single channels then anastomosing at distal segment. The malformation is usually believed as a benign condition without traces of thrombosis or dissection flaps, and merely diagnosed incidentally. However, coincidence of WCA with atherosclerosis or tachycardia may incur myocardium ischemia,[1] and even caused acute coronary syndrome (ACS) or sudden cardiac death (SCD) in reported cases.[2–4] Since the absence of evidence, the guideline for management of the coronary malformation is still lacking. Notably, as an intravascular image modality with high resolution,[5] optical coherence tomography (OCT) may shed lights on diagnosis and management of WCA.[2] Herein, we reported three cases of optimizing WCA management through performing OCT. 展开更多
关键词 FRACTIONAL flow RESERVE Optical COHERENCE tomography PERCUTANEOUS CORONARY INTERVENTION Woven CORONARY artery
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水平轴风力机模型测力试验研究 预览
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作者 马进骁 李永贵 +1 位作者 肖翅翔 李毅 《科技视界》 2019年第28期40-42,39共4页
在边界层风洞中对转动状态下的风力机模型进行了测力天平试验,研究了A、B两类地貌,0°桨距角,0°风向角时,风力机轮毂处两个轴向的风力系数,脉动风力功率谱和相干函数。结果表明:随着风轮转速的均匀增大,两个轴向的平均、脉动... 在边界层风洞中对转动状态下的风力机模型进行了测力天平试验,研究了A、B两类地貌,0°桨距角,0°风向角时,风力机轮毂处两个轴向的风力系数,脉动风力功率谱和相干函数。结果表明:随着风轮转速的均匀增大,两个轴向的平均、脉动风力系数呈现出非均匀增大的现象;风轮转速为300rpm时,在折减频率为4Hz、6Hz处分别出现了风轮转动、天平-模型共振引起的谱峰。 展开更多
关键词 水平轴风力机 风洞试验 测力天平 风力系数 风力功率谱 相干性
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相干与信息守恒及其在Mach-Zehnder干涉中的应用 预览
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作者 傅双双 骆顺龙 孙源 《物理学报》 SCIE EI CAS CSCD 北大核心 2019年第3期7-12,共6页
自量子力学诞生以来,相干性和互补性一直是被广泛而深入研究的两个重要课题.随着量子信息近年来的发展,人们引入了若干度量来定量地刻画相干性和互补性.本文建立两个信息守恒关系式,分别基于'Bures距离-保真度'和'对称-非对... 自量子力学诞生以来,相干性和互补性一直是被广泛而深入研究的两个重要课题.随着量子信息近年来的发展,人们引入了若干度量来定量地刻画相干性和互补性.本文建立两个信息守恒关系式,分别基于'Bures距离-保真度'和'对称-非对称',并且利用它们来刻画相干性和互补性.具体来说,首先从信息守恒的观点解释Bures距离和保真度的互补关系,并由此自然推导出Mach-Zehnder干涉仪中的Englert'干涉-路径'互补关系.其次在量子态和信道相互作用的一般框架中讨论'对称-非对称'信息守恒关系,并揭示其与Bohr互补性和量子相干性的内在联系.最后,在Mach-Zehnder干涉仪中探讨相干、退相干及互补性,刻画两个信息守恒关系之间的密切联系. 展开更多
关键词 相干 互补性 信息守恒 MACH-ZEHNDER干涉仪
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Optical coherence tomography findings in chronic progressive external ophthalmoplegia
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作者 Yuan Wu Lei Kang +2 位作者 Hai-Long Wu Yue Hou Zhao-Xia Wang 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第10期1202-1207,共6页
Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial encephalomyopathy caused by multiple mtDNA abnormalities. There is little information about the changes of ocular fundus with CPEO. Th... Background: Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial encephalomyopathy caused by multiple mtDNA abnormalities. There is little information about the changes of ocular fundus with CPEO. The aim of this work was to measure and evaluate changes in the macular retinal thickness and optic nerve head in patients with CPEO using spectral-domain optical coherence tomography and to compare the findings with those of healthy individuals. Methods: Totally, 18 CPEO patients were enrolled in this study. Healthy volunteers matched for gender, age, and diopter settings were included as a control group. The retinal thickness of macular central fovea, inner and outer retinal layer thickness of perifoveal macular, optic nerve head parameters, and peripapillay retinal nerve fiber layer thickness (pRNFLT) for all included cases were measured using spectral-domain optical coherence tomography. A paired t test was used to compare the differences in the studied parameters between the two groups. The correlations between macular retinal thickness, pRNFLT, disease duration, and age of onset were also analyzed. Results: Among the macular parameters, retinal thickness of macular central fovea (t=—2.135, P < 0.05) and outer retinal layer thickness (t =—1.994, P < 0.05) of patients in the CPEO group were statistically significant lower than those of patients in the normal control group. For the optic nerve head parameters, the patients in the CPEO group showed a larger rim volume (t =—2.499, P < 0.05) and nerve head volume (t =—2.103, P < 0.05). The overall pRNFLT of patients in the CPEO group was statistically significant lower than that of patients in the control group (t =—4.125, P < 0.05). The comparison of pRNFLT in eight sectors showed that the pRNFLT of patients in the CPEO group was statistically significant lower than that of the control group mainly in the inferior and temporal sectors. The degree of pRNFL defect negatively correlated with the disease duration (r =—0.583, P < 0.05). Conclus 展开更多
关键词 Optical COHERENCE tomography Chronic PROGRESSIVE external OPHTHALMOPLEGIA RETINA NERVE fiber layer
影响激光全息照相实验成像效果的因素解析 预览
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作者 杨超舜 尹剑波 +1 位作者 侯泉文 庞述先 《物理与工程》 2019年第3期63-67,75共6页
激光全息照相实验是近代物理实验的重要实验之一,实验中的一些因素将影响成像效果,对这些因素作具体分析,有助于提升激光全息照相实验的成像效果。从激光全息照相基本原理出发,结合实验室具体条件,配合直观图解,对物光与参考光的光程差... 激光全息照相实验是近代物理实验的重要实验之一,实验中的一些因素将影响成像效果,对这些因素作具体分析,有助于提升激光全息照相实验的成像效果。从激光全息照相基本原理出发,结合实验室具体条件,配合直观图解,对物光与参考光的光程差、物光与参考光的夹角、曝光显影定影过程、物光与参考光的强度比、物与全息干版相对位置等因素作了详细分析与解释,给出了最优参数。这些解释和优化参数有效提高了课堂上实验的效率及成像效果,有助于学生更深入地理解激光全息照相实验的原理,提升学生的物理实验技能。 展开更多
关键词 激光全息照相 成像效果 光程差 相干性 显影 定影
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Performance gain bounds of coherently combining multiple radars in a target-based calibration manner 预览
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作者 LIU Xinghua XU Zhenhai XIAO Shunping 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第2期278-287,共10页
To achieve a high signal-to-noise ratio(SNR) while maintaining moderate radar antenna, a target-based calibration manner is available to coherently combine multiple radars. The key to this calibration manner is to est... To achieve a high signal-to-noise ratio(SNR) while maintaining moderate radar antenna, a target-based calibration manner is available to coherently combine multiple radars. The key to this calibration manner is to estimate coherence parameters(CPs), i.e., time and phase calibration values in transmission and reception estimation, by separating the target returns into monostatic and bistatic echoes. However, CPs estimations exist uncertainties, which will affect the performance gain after multiradar coherent combination. The principle of coherently combining multiple radars is elaborated and the signal probability model for CPs estimation is established. On this basis, CPs Cramer-Rao bound(CRB) is derived in the closed-form, according to which the non-tight and tight upper bounds for multiple radars coherent combination performance gain are derived in the closed-form and via Monte Carlo(MC) simulations, respectively. Simulations validate the correctness of the derived CRB and gain bounds. 展开更多
关键词 coherently COMBINING MULTIPLE radars Cramer-Rao bound (CRB) COHERENCE gain
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Strong Superadditive Deficit of Coherence and Quantum Correlations Distribution
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作者 刘思远 吴风霖 +1 位作者 张耀中 范桁 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第8期14-18,共5页
The definitions of strong superadditive deficit for relative entropy coherence and monogamy deficit of measurement-dependent global quantum discord are proposed.The equivalence between them is proved,which provides a ... The definitions of strong superadditive deficit for relative entropy coherence and monogamy deficit of measurement-dependent global quantum discord are proposed.The equivalence between them is proved,which provides a useful criterion for the validity of the strong superadditive inequality of relative entropy coherence.In addition,the strong superadditive deficit of rela.tive entropy coherence is proved to be greater than or equal to zero under the condition that bipartite measurement-dependent global quantum discord(GQD)does not increase under the discarding of subsystems.Using the Monte Carlo method,it is shown that both the strong superadditive inequality of relative entropy coherence and the monogamy inequality of measurement-dependent GQD are established under general circumstances.The bipartite measurement-dependent GQD does not increase under the discarding of subsystems.The multipartite situation is also discussed in detail. 展开更多
关键词 DEFICIT COHERENCE QUANTUM
Relationship between early structural changes at cornea incision sites and surgical outcomes after phacoemulsification
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作者 Kyung Hyun Jin Tae Gi Kim 《国际眼科杂志:英文版》 SCIE CAS 2019年第7期1139-1145,共7页
AIM: To assess the early structural changes at clear corneal cataract incision sites and surgical outcomes using anterior segment optical coherence tomography(AS-OCT).METHODS: We evaluated 80 eyes of 59 patients who u... AIM: To assess the early structural changes at clear corneal cataract incision sites and surgical outcomes using anterior segment optical coherence tomography(AS-OCT).METHODS: We evaluated 80 eyes of 59 patients who underwent phacoemulsification with a clear corneal incision. All incisions were evaluated 1 wk, 1, and 3 mo postoperatively using AS-OCT and analyzed regarding angle, length of the incision, maximal corneal thickness at the incision, and if present, corneal endothelial gap length and incision gap area. The patients were divided into two groups according to whether or not an endothelial gap was present at 1 wk postoperatively(endothelial gap, group 1;no endothelial gap, group 2). We analyzed the difference in patient and surgical factors between the two groups, and compared the surgical outcome and the refractive outcome.RESULTS: An endothelial gap was observed in 56(70.0%) of 80 eyes at 1 wk postoperatively but not at 3 mo postoperatively. The mean patient age was significantly higher in group 1 than in group 2. The longer the length of the corneal incision and the steeper the incision angle, the greater the length and area of the endothelial gap. In group 1, the mean change in mean keratometry of the anterior cornea was significantly greater than in group 2, and the spherical equivalent(SE) and mean numerical error indicated significant myopic changes at 1 wk postoperatively. CONCLUSION: The risk of an endothelial gap increases with patient age and a long corneal incision and steep incision angle. The presence of an endothelial gap aftersurgery may affect the early postoperative corneal curvature and SE. 展开更多
关键词 CORNEAL INCISION structure PHACOEMULSIFICATION CORNEAL CURVATURE CORNEAL endothelial gap ANTERIOR segment optical COHERENCE tomography
Segmentation of retinal fluid based on deep learning:application of three-dimensional fully convolutional neural networks in optical coherence tomography images
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作者 Meng-Xiao Li Su-Qin Yu +4 位作者 Wei Zhang Hao Zhou Xun Xu Tian-Wei Qian Yong-Jing Wan 《国际眼科杂志:英文版》 SCIE CAS 2019年第6期1012-1020,共9页
AIM: To explore a segmentation algorithm based on deep learning to achieve accurate diagnosis and treatment of patients with retinal fluid.METHODS: A two-dimensional(2D) fully convolutional network for retinal segment... AIM: To explore a segmentation algorithm based on deep learning to achieve accurate diagnosis and treatment of patients with retinal fluid.METHODS: A two-dimensional(2D) fully convolutional network for retinal segmentation was employed. In order to solve the category imbalance in retinal optical coherence tomography(OCT) images, the network parameters and loss function based on the 2D fully convolutional network were modified. For this network, the correlations of corresponding positions among adjacent images in space are ignored. Thus, we proposed a three-dimensional(3D) fully convolutional network for segmentation in the retinal OCT images.RESULTS: The algorithm was evaluated according to segmentation accuracy, Kappa coefficient, and F1 score. For the 3D fully convolutional network proposed in this paper, the overall segmentation accuracy rate is 99.56%, Kappa coefficient is 98.47%, and F1 score of retinal fluid is 95.50%. CONCLUSION: The OCT image segmentation algorithm based on deep learning is primarily founded on the 2D convolutional network. The 3D network architecture proposed in this paper reduces the influence of category imbalance, realizes end-to-end segmentation of volume images, and achieves optimal segmentation results. The segmentation maps are practically the same as the manual annotations of doctors, and can provide doctors with more accurate diagnostic data. 展开更多
关键词 optical COHERENCE tomography IMAGES FLUID segmentation 2D fully convolutional NETWORK 3D fully convolutional NETWORK
Narrow linewidth two-color polarization spectroscopy due to the atomic coherence effect in a ladder-type atomic system
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作者 杨保东 张锦芳 王军民 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第9期95-100,共6页
An experimental investigation of two-color polarization spectroscopy(TCPS) is presented based on the cesium 6 S1/2– 6P3/2– 8S1/2(852.3 nm + 794.6 nm) ladder-type system in a room-temperature vapor cell. The dependen... An experimental investigation of two-color polarization spectroscopy(TCPS) is presented based on the cesium 6 S1/2– 6P3/2– 8S1/2(852.3 nm + 794.6 nm) ladder-type system in a room-temperature vapor cell. The dependency of line shapes of TCPS on the power of a 852.3 nm pump and a 794.6 nm probe laser is measured in detail, and we confirm that the linewidth of TCPS in a counter-propagating configuration between the pump and probe laser beams is obviously narrower than that of a co-propagating configuration, due to the atomic coherence effect. It is helpful for laser stabilization of the excited state transition using TCPS without frequency modulation. 展开更多
关键词 two-color POLARIZATION spectroscopy(TCPS) ATOMIC COHERENCE effect ladder-type ATOMIC system
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