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Impact Point Prediction and Lateral Correction Analysis of Two-dimensional Trajectory Correction Projectiles 被引量:7
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作者 WANG Zhongyuan CHANG Sijiang 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第1期64-69,共6页
Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also ... Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research. 展开更多
关键词 control and navigation technology of aerocraft trajectory correction damping disk TRAJECTORY ballistic drift impact point prediction
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Hot-Spot Detection System with Correction of Operating Point for PV Generation System
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作者 Kazutaka Itako Naoaki Iiduka +1 位作者 Tsugutomo Kudoh Keishin Koh 《Journal of Energy and Power Engineering》 2017年第12期789-794,共6页
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ICESat-2水深提取方法及其反演应用
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作者 胡琪鑫 程亮 +2 位作者 楚森森 程俭 徐亚 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第3期997-1012,共16页
相比于传统水深测量方法,结合主动激光卫星ICESat-2数据与被动光学遥感影像的主被动融合水深反演方法具有低成本、覆盖面积广、不受地域限制、无需地面实测数据等优点.研究选取澳大利亚大堡礁中部的John Brewer Reef和南部的Fitzroy Ree... 相比于传统水深测量方法,结合主动激光卫星ICESat-2数据与被动光学遥感影像的主被动融合水深反演方法具有低成本、覆盖面积广、不受地域限制、无需地面实测数据等优点.研究选取澳大利亚大堡礁中部的John Brewer Reef和南部的Fitzroy Reef为实验区,开展主被动融合水深反演实验.针对ICESat-2光子点群信噪比低、光子点水深信息提取和改正难的问题,本文提出基于光子点群高斯分布特征的海面光子点群提取方法和基于深度自适应DBSCAN的海底光子点群提取方法,并顾及海面倾斜引起的入射角偏移,改进了Parrish水体折射改正几何模型.实验表明,基于光子点群高斯分布特征的海面光子点群提取方法和基于深度自适应DBSCAN的海底光子点群提取方法可以高效准确地提取出有效的海面、海底光子点群;经过地球物理改正和基于改进模型的水体折射改正后,水深变浅,且改正项与改正前水深呈线性关系,线性系数约为-0.2550.实验将提取并改正后的ICESat-2光子点水深与经大气校正、耀斑校正、空间域滤波等预处理后的Sentinel-2影像进行空间匹配构建水深反演样本集,并利用单波段模型(SB)、比值模型(BR)、Lyzenga多项式模型(LP)、二次多项式模型(QP)、三次多项式模型(CP)、支持向量回归模型(SVR)、多层感知器模型(MLP)、随机森林回归模型(RF)等水深反演模型对实验区全域水深进行反演.通过对比分析多种水深反演模型在不同地理区域和ICESat-2水深样本分布条件下的表现,研究为不同场景下的主被动融合水深反演策略提供了一定的科学依据. 展开更多
关键词 ICESat-2 Sentinel-2 光子点群提取 折射校正 水深反演
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PPA BASED PREDICTION-CORRECTION METHODS FOR MONOTONE VARIATIONAL INEQUALITIES 被引量:1
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作者 何炳生 蒋建林 +1 位作者 钱迈建 许娅 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第1期14-30,共17页
In this paper we study the proximal point algorithm (PPA) based predictioncorrection (PC) methods for monotone variational inequalities. Each iteration of these methods consists of a prediction and a correction. The p... In this paper we study the proximal point algorithm (PPA) based predictioncorrection (PC) methods for monotone variational inequalities. Each iteration of these methods consists of a prediction and a correction. The predictors are produced by inexact PPA steps. The new iterates are then updated by a correction using the PPA formula. We present two profit functions which serve two purposes: First we show that the profit functions are tight lower bounds of the improvements obtained in each iteration. Based on this conclusion we obtain the convergence inexactness restrictions for the prediction step. Second we show that the profit functions are quadratically dependent upon the step lengths, thus the optimal step lengths are obtained in the correction step. In the last part of the paper we compare the strengths of different methods based on their inexactness restrictions. 展开更多
关键词 计算方法 最接近点计算法 预测方法 变量 不等式
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采用北斗PPP-B2b服务的大气可降水量反演及香港地区暴雨过程分析
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作者 程安坤 王敏 +2 位作者 孟欣 季锐 孙爽 《测绘通报》 CSCD 北大核心 2024年第2期118-123,共6页
北斗三号卫星导航系统精密单点定位服务(PPP-B2b服务)通过卫星B2b信号向用户发送改正信息,摆脱了对外部通信的依赖,为实时反演大气可降水量(PWV)提供了新的技术途径。本文利用试验分析了PPP-B2b服务反演PWV的精度。试验结果表明,利用PPP... 北斗三号卫星导航系统精密单点定位服务(PPP-B2b服务)通过卫星B2b信号向用户发送改正信息,摆脱了对外部通信的依赖,为实时反演大气可降水量(PWV)提供了新的技术途径。本文利用试验分析了PPP-B2b服务反演PWV的精度。试验结果表明,利用PPP-B2b服务反演结果与采用CODE事后精密星历产品的差值RMS为3.70 mm,STD为3.61 mm,与ERA5再分析数据差值的RMS和STD分别为4.80和4.07 mm,与探空结果差值的RMS和STD分别为3.75和7.16 mm,验证了采用PPP-B2b服务的PWV反演结果具有较好的精度。最后,通过分析香港地区暴雨过程的实际降水量与PWV反演结果之间的相关性,初步验证了BDS PPP-B2b服务用于暴雨灾害短时预警的可行性。 展开更多
关键词 大气可降水量反演 精密单点定位 北斗卫星导航系统 实时卫星轨道钟差改正 暴雨灾害短时预警
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不同电离层改正模型的SF-PPP定位精度分析
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作者 吴丕团 覃现 +3 位作者 韦佳 肖明虹 黄铭 杨钊 《全球定位系统》 CSCD 2024年第2期1-8,共8页
电离层延迟可严重制约单频接收机的定位精度.基于此,本文介绍了四种单频接收机常用的电离层延迟改正方法,包括广播电离层改正模型(策略1),顾及太阳位置的变化全球电离层格网产品(Global Ionosphere Map,GIM)时间旋转内插(策略2),GIM投... 电离层延迟可严重制约单频接收机的定位精度.基于此,本文介绍了四种单频接收机常用的电离层延迟改正方法,包括广播电离层改正模型(策略1),顾及太阳位置的变化全球电离层格网产品(Global Ionosphere Map,GIM)时间旋转内插(策略2),GIM投影函数改正(策略3)和半合改正模型(策略4).同时,选择不同太阳活动期,不同纬度的测站验证不同电离层改正方法的单频精密单点定位(single-frequency point positioning,SF-PPP)定位结果偏差.经过对比分析,得到如下结论:1)总体来说,半合改正模型得到的定位效果最佳,其次是使用GIM产品对电离层延迟进行改正,最后是广播电离层模型;2)在不同太阳活动跃期,不同策略在低纬度测站的定位偏差最大,其次是高纬度测站,中纬度测站的定位偏差最小;3)策略2和策略3在不同太阳活动期不同纬度测站的水平定位平差约0.150 m,三维定位偏差约0.700 m;策略4在不同太阳活动期不同纬度测站的水平定位偏差为0.100 m,三维定位偏差为0.500 m. 展开更多
关键词 单频接收机 电离层 电离层改正模型 单频精密单点定位(SF-PPP)
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基于萨哈-玻尔兹曼图与自吸收校正的单点修正激光诱导击穿光谱
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作者 胡桢麟 王天泽 +1 位作者 郭连波 林楠 《量子电子学报》 CAS CSCD 北大核心 2024年第3期455-462,共8页
为进一步提高单点修正激光诱导击穿光谱(OPC-LIBS)的定量分析精度,提出了基于萨哈-玻尔兹曼图与自吸收校正的OPC-LIBS方法,利用该方法对两个钛合金样品中的Ti、V和Al元素进行了定量分析,并将其定量结果与基于玻尔兹曼图的OPC-LIBS、基... 为进一步提高单点修正激光诱导击穿光谱(OPC-LIBS)的定量分析精度,提出了基于萨哈-玻尔兹曼图与自吸收校正的OPC-LIBS方法,利用该方法对两个钛合金样品中的Ti、V和Al元素进行了定量分析,并将其定量结果与基于玻尔兹曼图的OPC-LIBS、基于萨哈-玻尔兹曼图的OPC-LIBS以及基于玻尔兹曼图和自吸收校正的OPC-LIBS的结果进行了对比分析。研究结果表明,所提出的改进方法在4种方法中可获得最小的定量误差,测量两个钛合金样品中3种元素的平均相对误差(MREs)分别为4.11%和3.99%,证明所提出的改进方法可有效提高OPC-LIBS的定量分析精度。 展开更多
关键词 光谱学 单点修正激光诱导击穿光谱 萨哈-玻尔兹曼图 自吸收校正 等离子体温度
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SZT-R1000车载激光雷达测量系统在道路工程测量中的应用
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作者 王春来 王小丽 +1 位作者 王斐 黄悦东 《经纬天地》 2024年第1期67-70,75,共5页
本文针对道路工程测量的难点问题,采用SZT-R1000车载激光雷达测量系统,进行道路数据采集。对该方法应用于道路工程测量中的关键问题进行了探讨,同时提出了基于距离将误差值反向加权平差的方法对点云数据进行精度优化。经对比分析:该方... 本文针对道路工程测量的难点问题,采用SZT-R1000车载激光雷达测量系统,进行道路数据采集。对该方法应用于道路工程测量中的关键问题进行了探讨,同时提出了基于距离将误差值反向加权平差的方法对点云数据进行精度优化。经对比分析:该方案不仅数据采集效率高,而且数据精度可靠。经精度优化后的点云数据平面精度可以达到5 cm以内,高程精度可以达到3 cm以内,在道路工程项目中有广阔的应用前景。 展开更多
关键词 车载激光雷达 标靶布设 点云纠正
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Thermal Fission Rate Calculated Numerically by Particles Multi-passing over SaddlePoint 被引量:3
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作者 LIULing BAOJing-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期273-278,共6页
Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the proc... Langevin simulation of the particles multi-passing over the saddle point is proposed to calculate thermal fission rate.Due to finite friction and the corresponding thermal flutuation,a backstreaming exists in the process of the particle descent from the saddle to the scissio.This leads to that the diffusion behind the saddle point has influence upon the stationary flow across the saddle point.A dynamical correction factor,as a ratio of the flows of multi-and firstoverpassing the saddle point,is evaluated analytically.The results show that the fission rate calculated by the particles multi-passing over the saddle point is lower than the one calculated by the particle firstly passing over the saddle point,and the fomer approaches the results at the scission point. 展开更多
关键词 Langevin模拟 热裂变率 粒子多通道支座点 稳态流 动力学修正因素 粒子物理
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On ionosphere-delay processing methods for single-frequency precise-point positioning 被引量:1
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作者 Tu Rui Zhang Qin Huang Guanwen Zhao Hong 《Geodesy and Geodynamics》 2011年第1期71-76,共6页
In single-frequency precise-point positioning of a satellite,ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical p... In single-frequency precise-point positioning of a satellite,ionosphere delay is one of the most important factors impacting the accuracy. Because of the instability of the ionosphere and uncertainty of its physical properties, the positioning accuracy is seriously limited when using a precision-limited model for correction. In order to reduce the error, we propose to introduce some ionosphere parameter for real-time ionosphere-delay estimation by applying various mapping functions. Through calculation with data from the IGS( International GPS Service) tracking station and comparison among results of using several different models and mapping functions, the feasibility and effectiveness of the new method are verified. 展开更多
关键词 single-frequency precise-point positioning ionosphere delay model correction mapping function parameter estimation
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Performance analysis of real-time and post-mission kinematic precise point positioning in marine environments
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作者 Serdar Erol Reha Metin Alkan +1 位作者 I.Murat Ozulu Veli Ilçi 《Geodesy and Geodynamics》 2020年第6期401-410,共10页
This article focuses on the performance analysis of both real-time and post-mission kinematic precise point positioning(PPP)in challenging marine environments.For this purpose,a real dynamic experiment lasting 6 h was... This article focuses on the performance analysis of both real-time and post-mission kinematic precise point positioning(PPP)in challenging marine environments.For this purpose,a real dynamic experiment lasting 6 h was carried out on a lake dam in?orum City of Turkey.While the kinematic test was continuing,the real-time PPP coordinates were obtained for each measurement epoch with a commercial real-time PPP(RT-PPP)service,namely the Trimble Center Point RTX.Then the post-mission PPP(PM-PPP)coordinates were calculated by using Multi-GNSS data and the Multi-GNSS Experiment(MGEX)precise products.The kinematic RT-PPP and PM-PPP results showed that the PPP coordinates were consistent with the relative solution at centimetre and decimetre level in horizontal and height components,respectively.This study implies that PPP technique is a powerful tool for highly accurate positioning in both real-time and post-mission modes,even for dynamic applications in harsh environments. 展开更多
关键词 Kinematic survey Precise point positioning Real-time PPP IGS-RTS Global GNSS correction service
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Simulation Model of Mechanical Properties of Point - Bonded Nonwovens
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作者 李作攀 储才元 《Journal of China Textile University(English Edition)》 EI CAS 1999年第2期43-45,共3页
A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical p... A computer model for studying the mechanical properties of point - bonded nonwovens is established. The simulation tensile curve of a nonwoven fabric may be obtained based on relaxation procedure when the mechanical properties of fibers, the arrangement of bond points in the fibrous web and specimen size are inputted into the computer. Relaxation method and relevant algorithms of computer simulation are described in detail. The validity of the model is also demonstrated. 展开更多
关键词 Computer SIMULATION point - BOND Non-wovem MECHANICAL Properties
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GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——
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作者 周晋康 《苏州大学学报(工科版)》 CAS 1992年第S2期27-34,共8页
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we... By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points. 展开更多
关键词 Ball’s point centering - point CURVE and CIRCLING CURVE four ISPS Coupler curves based on BALLS pointS
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Coupled Fixed Point for (<i>&alpha;</i>, <i>&Psi;</i>)-Contractive in Partially Ordered Metric Spaces Using Compatible Mappings
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作者   Preeti Sanjay Kumar 《Applied Mathematics》 2015年第8期1380-1388,共9页
In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and g... In this paper, first we introduce notions of (α, Ψ)-contractive and (α)-admissible for a pair of map and prove a coupled coincidence point theorem for compatible mappings using these notions. Our work extends and generalizes the results of Mursaleen et al. [1]. At the end, we will provide an example in support of our result. 展开更多
关键词 Coupled COINCIDENCE point α-ψ-Contractive Mapping Compatible MAPPINGS
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A Stylistic Analysis of an Excerpt from The Corrections
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作者 陈尚文 《海外英语》 2019年第19期211-212,238,共3页
This article focuses on analyzing the excerpt from The Corrections written by Jonathan Franzen.The analysis shed light on the participating characters(Chip and his father,Alfred)by exploring the point of view of the a... This article focuses on analyzing the excerpt from The Corrections written by Jonathan Franzen.The analysis shed light on the participating characters(Chip and his father,Alfred)by exploring the point of view of the author and on the peculiarities of their family relationship as well as the emotional change of Chip. 展开更多
关键词 The correctionS point of VIEW FAMILY RELATIONSHIP
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Epidemio-Clinical, Therapeutic and Evolutive Aspects of Pulmonary Embolism in Young Subject in the Cardiology Department in Point “G” Hospital University Center Bamako
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作者 M. Sako S. Sidibé +12 位作者 M. Konaté B. Sonfo N. Diallo M. Diakité C. Thiam A. Keita I. Sangaré H. O. Ba Y. Camara L. Bouaré Y. R. Koumaré S. Coulibaly I. Minta 《Open Journal of Epidemiology》 2020年第4期393-398,共6页
<strong>Objective:</strong> The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of th... <strong>Objective:</strong> The purpose of this work was to determine the epidemiological, clinical and evolutionary aspects of the pulmonary embolism of the young person in the cardiology department of the University Hospital Center (CHU) Point G in Bamako-Mali. <strong>Methodology:</strong> This was an analytical study from January 01, 2018 to December 31, 2018 in the CHU Point G cardiology department, including all patients hospitalized during this period. <strong>Results:</strong> Of 1379 hospitalized patients, 19 patients were concerned by pulmonary embolism of the young person. The prevalence of pulmonary embolism of the young person was 1.37%. The most affected age group was 21 - 30 (47.4%) of patients. The predominance was female (89.47%) with a gender ratio of 0.11 in favour of women. The average age in the series was 29.79 years with extremes of 16 years and 40 years. Factors predisposing to pulmonary embolism were dominated by peri partum, cardiomyopathy and obesity with 47.3%, 31.57% and 21.1%, respectively. The dominant signs were chest pain and dyspnea in 94.7% and 89.5% of cases respectively. Pulmonary embolism was unlikely in 60.52% according to the Geneva and Wells score simplified. At the thoracic angioscanner, the embolism was bilateral in 52.6% of cases and distal in 36.8% of patients;in 10 patients who performed cardiac ultrasound, pulmonary arterial hypertension (70%), dilation of the right ventricle (20%) and left ventricular dilation (40%). Hyper leucocytosis (47.4%), anemia and low prothrombin rate (TP) (22.2%) were the most found biological abnormalities. More than 2/3 (68.5%) our patients had an intermediate mortality risk according to the PESI (Pulmonary Embolism Severity Index) score. The average hospital stay was 10 days. Hospital mortality was 10.5%. <strong>Conclusion:</strong> The pulmonary embolism of the young person is a frequent, serious and multifactorial pathology and the female sex is most affected especially during peri partum periods, hence the need for preventive measures. Clinical signs are not specific and based on the assessment of clinical probability. Pulmonary angioscanner remains the confirmation review in our context. 展开更多
关键词 Pulmonary Embolism Young Subject 15 - 40 Years CARDIOLOGY point G Hospital
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Cross-Correlation Detection of Point Sources in the WMAP First Year Data
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作者 Jian-Yin Nie Shuang-Nan Zhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第2期199-208,共10页
We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We... We apply a Cross-Correlation (CC) method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources. 展开更多
关键词 cosmic microwave background: WMAP - cross-correlation - radio point source
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Base-out恢复点为目标手术量的急性共同性内斜视治疗效果分析 被引量:1
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作者 黄静 强军 +4 位作者 刘猛 杨诗永 刘娟娟 徐深 范洪雨 《现代科学仪器》 2023年第1期83-86,共4页
目的:探讨Base-out恢复点为目标手术量的急性共同性内斜视(AACE)治疗效果。方法:收治60例AACE患者,对患者进行Base-out恢复点为目标手术量的治疗干预。对比手术效果、Base-out恢复点参数、立体视觉恢复及影响因素。结果:术后左眼、右眼... 目的:探讨Base-out恢复点为目标手术量的急性共同性内斜视(AACE)治疗效果。方法:收治60例AACE患者,对患者进行Base-out恢复点为目标手术量的治疗干预。对比手术效果、Base-out恢复点参数、立体视觉恢复及影响因素。结果:术后左眼、右眼近视屈光度高于术前,术后近距、远距斜视度低于术前(P<0.05)。术后Base-out恢复点近距、远距均低于术前,术后的BI恢复点包括近距、远距高于术前(P<0.05)。结论:AACE患者采用基于Base-out恢复点为目标手术量有较好的治疗效果,改善立体视觉功能。 展开更多
关键词 急性共同性内斜视 Base-out恢复点 眼位矫正 立体视觉
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CAS 132-2006 Standard for Flat Panel Display TV Set Installation Service Formulating and Enforcing Main Point Explanation and Analysis
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作者 TCL group, TTE China Business Center Technical Service Depart-ment. 《China Standardization》 2007年第4期26-31,共6页
  CAS 132-2006 formulation background and work courses   Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower ...   CAS 132-2006 formulation background and work courses   Flat panel display technology is maturing alongside the development of science and technology. The prices of flat panel display TV sets are becoming lower and lower. Flat panel display TV sets have begun entering the mainstream and are now the first choice of some consumers when making new TV purchases.Display TV Set Installation Service Point Explanation and AnalysisRepair, Retreat and Change Duty Stipulations. Peculiar use conditions, usage environments, and the practical circumstances of user consumption service requirements, etc., were also taken into account on the basis of extensive investigation, testing, and verification.…… 展开更多
关键词 TV In CAS 132-2006 Standard for Flat Panel Display TV Set Installation Service Formulating and Enforcing Main point Explanation and An
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北斗三号PPP-B2b精密单点定位性能评估
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作者 王春阳 《城市勘测》 2023年第6期83-85,共3页
北斗三号通过GEO卫星的B2b信号向亚太区域用户提供实时精密单点定位服务PPP-B2b,对其定位性能的评估可以为用户选择精密单点定位服务提供重要参考。利用卫星播发的精密改正信息和广播星历恢复精密轨道和钟差产品,在此基础上采用无电离... 北斗三号通过GEO卫星的B2b信号向亚太区域用户提供实时精密单点定位服务PPP-B2b,对其定位性能的评估可以为用户选择精密单点定位服务提供重要参考。利用卫星播发的精密改正信息和广播星历恢复精密轨道和钟差产品,在此基础上采用无电离层组合进行精密单点定位,对PPP-B2b定位能力进行细致评估,结果表明动态定位实验中BDS-3单系统一小时收敛后的平面和高程精度分别为13.8 cm和14.9 cm,而BDS-3/GPS双系统联合定位仅需20 min即可收敛到平面20 cm的定位精度,一小时后的平面和高程定位精度分别可达6.1 cm和8.7 cm,双系统定位的收敛速度明显快于单系统。 展开更多
关键词 实时精密单点定位 精密改正信息 无电离层组合 定位精度
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