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人工法off-line HDF对血液透析充分性和高同型半胱氨酸血症的影响
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作者 吴飞飞 罗来敏 +2 位作者 范燕娜 张桂玲 龚燕燕 《实用临床医学(江西)》 CAS 2024年第4期19-22,27,共5页
目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6... 目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6个月。前3个月维持每周2次高通量血液透析(HFHD)联合1次on-line HDF,后3个月维持每周2次人工法off-line HDF联合1次on-line HDF。于研究第3个月、第6个月时用全自动生化分析仪检测透析前后血尿素氮(BUN)、血肌酐(SCr)、β2-微球蛋白(β2MG)、同型半胱氨酸(Hcy)、白蛋白(Alb)、C反应蛋白(CRP)、血红蛋白(Hb)、甲状旁腺素(iPTH)、磷(P)、钾(K)水平;计算血清尿素清除指数(Kt/V)、尿素下降率(URR)和β2MG清除率。结果人工法off-line HDF模式透析的Kt/V、URR及β2MG清除率均较显著高于HFHD模式透析(P<0.05);人工法off-lineHDF模式透析Kt/V、URR及β2MG清除率达到透析充分的百分率分别为83.33%、83.33%和93.33%,均显著高于HFHD模式透析(P<0.05)。与HFHD模式透析时相比,人工法off-lineHDF模式透析结束后,患者透析前Hcy水平降低,Alb水平升高(P<0.05)。结论人工法off-line HDF模式透析可显著增加Kt/V、URR和β2MG清除率,提高MHD患者的透析充分性达标率,且对HHcy具有改善作用。 展开更多
关键词 人工法off-line HDF 血液透析 透析充分性 高同型半胱氨酸血症 血液透析滤过
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一个改进的陆面过程模式及其模拟试验研究第一部分:陆面过程模式及其“独立(off-line)”模拟试验和模式性能分析 被引量:42
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作者 张晶 丁一汇 《气象学报》 CSCD 北大核心 1998年第1期1-19,共19页
文中在综合比较过去各类陆面过程模式优缺点的基础上,主要参考BATS模式,发展了一个陆面过程模式(LPM-ZD)。它具有以下几个特征:1.采用物理方程和经验解析公式相结合的方法进行土壤温度和土壤水汽的求解。在上层土壤,... 文中在综合比较过去各类陆面过程模式优缺点的基础上,主要参考BATS模式,发展了一个陆面过程模式(LPM-ZD)。它具有以下几个特征:1.采用物理方程和经验解析公式相结合的方法进行土壤温度和土壤水汽的求解。在上层土壤,土壤分层较细并采用温度传导和水汽扩散方程求解,而在下层土壤,土壤分层较粗并利用经验方法处理。2.考虑了降水分布的次网格特征及其对陆面水文产生的重要影响。3.较全面地考虑了雪盖对陆面过程的各种影响:对陆面水文的影响、对土壤热传导的影响以及雪盖的高反照率对辐射收支的影响。利用3组单点观测试验资料对陆面过程模式LPM-ZD进行了“独立(of-line)”模拟试验。模拟结果表明陆面过程模式LPM-ZD具有较好的模拟性能,能够比较准确地模拟不同气候区的多种下垫面类型的陆面过程变化特点,模拟结果与观测基本一致。进而又利用一组观测资料和模式LPM-ZD进行了一系列敏感性模拟试验,试验结果表明模式LPM-ZD对一些参数的确定非常敏感,如初始土壤水汽、植被的物理特性参数以及降水次网格分布因子等,因此提高确定这些参数的准确性是改进陆面模式的重要内容之一。 展开更多
关键词 陆面过程模式 模拟试验 大气模式 模式性能
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一个实用的off-line公平电子现金系统 被引量:2
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作者 高虎明 毛剑 王育民 《电子学报》 EI CAS CSCD 北大核心 2003年第2期196-198,共3页
本文提出的off line公平电子现金系统具有以下特点 :能保护合法用户的匿名性 ;可追踪非法用户 ;非法者不能敲诈用户 ;他人获得合法用户的电子现金不可盗用 ;银行与用户之间发生重复花费的争议时可仲裁 ;银行与信任机构都是脱线的 .虽然... 本文提出的off line公平电子现金系统具有以下特点 :能保护合法用户的匿名性 ;可追踪非法用户 ;非法者不能敲诈用户 ;他人获得合法用户的电子现金不可盗用 ;银行与用户之间发生重复花费的争议时可仲裁 ;银行与信任机构都是脱线的 .虽然信任机构要维护一个与银行相同数量级的数据库 ,但换来了申请。 展开更多
关键词 脱线公平电子现金 广义EIGamal签字 eCash^TM
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Study on general inverse kinematics of rotating/tilting positioner for robotic arc welding off-line programming 被引量:3
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作者 田劲松 吴林 戴明 《China Welding》 EI CAS 2001年第1期27-33,共7页
Off line programming provides an essential link between CAD and CAM, whose development will result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is one of... Off line programming provides an essential link between CAD and CAM, whose development will result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is one of the most typical workcells. The inverse kinematics of robot and positioner is the foundation of the off line programming system. The previous researchers only focused on a special solution of the positioner inverse kinematics, which is the solution at down hand welding position. In this paper, we introduce a method for representing welding position. Then a general algorithm of rotating/tilting positioner inverse kinematics is presented, and an approach to find the unique solution of the inverse kinematics is discussed. The simulation experiment results show that the general algorithm can improve the ability of robotic arc welding off line programming system to program all types of welding positions. 展开更多
关键词 robotic arc welding off line programming rotating/tilting positioner inverse kinematics
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Offline Arabic character recognition system
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作者 黄建华 唐降龙 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期80-88,共9页
Several languages use the Arabic alphabets and Arabic scripts present challenges because the letter shape is context sensitive. For the past three decades, there has been a mounting interest among researchers in this ... Several languages use the Arabic alphabets and Arabic scripts present challenges because the letter shape is context sensitive. For the past three decades, there has been a mounting interest among researchers in this problem. In this paper we present an Arabic Character Recognition system and review the theory behind the Arabic recognition system, the characteristics of Arabic writing, the sequence steps of recognizing Arabic text. These steps are separately discussed, and previous research work on each step is reviewed. Also in this paper we give some samples of Arabic fonts. 展开更多
关键词 RECOGNITION off line Arabic character
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分布式水文-土壤-植被模式的改进及气候水文Off-line模拟试验 被引量:25
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作者 王守荣 黄荣辉 +3 位作者 丁一汇 L.R.Leung M.S.Wigmosta L.W.Vail 《气象学报》 CSCD 北大核心 2002年第3期290-300,共11页
文中对引进的高分辨率 (94 2 .5m× 94 2 .5m)分布式水文 土壤 植被模式 (DHSVM) ,针对海、滦河流域的特点进行了改进 ,主要包括 :(1)改变蒸散发模拟方法 ,用改进的Penman Monteith模式模拟海滦河流域的蒸发 ,较好地模拟出 1a内的... 文中对引进的高分辨率 (94 2 .5m× 94 2 .5m)分布式水文 土壤 植被模式 (DHSVM) ,针对海、滦河流域的特点进行了改进 ,主要包括 :(1)改变蒸散发模拟方法 ,用改进的Penman Monteith模式模拟海滦河流域的蒸发 ,较好地模拟出 1a内的两个峰值 ,最大值出现在 4~ 6月 ,次大值出现在 7~ 8月 ;(2 )改变水文模式结构 ,用多站点气候观测资料内插到模式网格点 ,充分实现了分布式水文模拟 ;(3)发展新的水文、植被、土壤参数化方案 ,对 33个参数分区计算和确定 ,并重点对土壤孔隙度 φ、土壤蓄水能力θfc、叶面指数LAI、随机阻抗γs 等 11个参数进行调试和修订 ,提高了水文模拟精度。用改进的DHSVM模式分别对滦河、桑干河流域蒸散发、地下水位、土壤湿度、土壤水下渗、产流、汇流与径流等水文过程进行Off line模拟试验 ,模拟结果与实测值一致性较好 ,滦河流域 1979~ 1991年、桑干河流域 1979~ 1987年水文模拟效率系数分别为 0 .89和 0 .82 。 展开更多
关键词 土壤 植被 改进 水文模式 off-line模拟试验 模拟效率系数 地下水位 气候 土壤湿度 产流 汇流
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A Land Surface Model(IAP94) for Climate Studies PartI:Formulation and Validation in Off-line Experiments 被引量:57
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作者 戴永久 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1997年第4期2-29,共23页
The IAP (Institute of Atmospheric Physics) land-surface model (IAP94) is described. This model is a comprehensive one with detailed description for the processes of vegetation, snow and soil. Particular attention has ... The IAP (Institute of Atmospheric Physics) land-surface model (IAP94) is described. This model is a comprehensive one with detailed description for the processes of vegetation, snow and soil. Particular attention has been paid to the cases with three water phases in the surface media. On the basis of the mixture theory and the theory of fluid dynamics of porous media, the system of universal conservational equations for water and heat of soil, snow and vegetation canopy has been constructed. On this background, all important factors that may affect the water and heat balance in media can be considered naturally, and each factor and term possess distinct physical meaning. In the computation of water content and temperature, the water phase change and the heat transportation by water flow are taken into account. Moreover, particular attention has been given to the water vapor diffusion in soil for arid or semi-arid cases, and snow compaction. In the treatment of surface turbulent fluxes, the difference between aerodynamic and thermal roughness is taken into account. The aerodynamic roughness of vegetation is calculated as a function of canopy density, height and zero-plane displacement. An extrapolation of log linear and exponential relationship is used when calculating the wind profile within canopy. The model has been validated against field measurements in off-line simulations. The desirable model′s performance leads to the conclusion that the IAP94 is able to reproduce the main physical mechanisms governing the energy and water balances in the global land surface. Part II of the present study will concern the validation in a 3-D experiment coupled with the IAP Two-Level AGCM. 展开更多
关键词 Land Surface Model off-line Experiment VALIDATION
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Designing and Optimization of an Off-line Programming System for Robotic Belt Grinding Process 被引量:11
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作者 WANG Wei YUN Chao +1 位作者 ZHANG Ling GAO Zhihui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期647-655,共9页
Off-line programming (OLP) system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the... Off-line programming (OLP) system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the OLP system. A new type of grinding robot and a novel robotic belt grinding workcell are forwarded, and their features are briefly introduced. An open and object-oriented off-line programming system is developed for this robotic belt grinding system. The parameters of the trimmed surface are read from the initial graphics exchange specification (IGES) file of the CAD model of the workpiece. The deBoor-Cox basis function is used to sample the grinding target with local contact frame on the workpiece. The numerical formula of inverse kinematics is set up based on Newton's iterative procedure, to calculate the grinding robot configurations corresponding to the grinding targets. After the grinding path is obtained, the OLP system turns to be more effective than the teach-by-showing system. In order to improve the grinding workspace, an optimization algorithm for dynamic tool frame is proposed and performed on the special robotic belt grinding system. The initial tool frame and the interval of neighboring tool frames are defined as the preparation of the algorithm. An optimized tool local frame can be selected to grind the complex surface for a maximum dexterity index of the robot. Under the optimization algorithm, a simulation of grinding a vane is included and comparison of grinding workspace is done before and after the tool frame optimization. By the algorithm, the grinding workspace can be enlarged. Moreover the dynamic tool frame can be considered to add one degree-of-freedom to the grinding kinematical chain, which provides the theoretical support for the improvement of robotic dexterity for the complex surface grinding. 展开更多
关键词 off-line programming robotic belt grinding path generation tool optimization
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An off-line simulation of land surface processes over the northern Tibetan Plateau 被引量:2
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作者 MinHong Song YaoMing Ma +2 位作者 Yu Zhang WeiQiang Ma SiQiong Luo 《Research in Cold and Arid Regions》 CSCD 2014年第3期236-246,共11页
In order to further understand the land surface processes over the northern Tibetan Plateau, this study produced an off-line simulated examination at the Bujiao site on the northern Tibetan Plateau from June 2002 to A... In order to further understand the land surface processes over the northern Tibetan Plateau, this study produced an off-line simulated examination at the Bujiao site on the northern Tibetan Plateau from June 2002 to April 2004, using the Noah Land Surface Model (Noah LSM) and observed data from the CAMP/Tibet experiment. The observed data were neces- sarily corrected and the number of soil layers in the Noah LSM was changed from 4 to 10 to enable this off-line simulation and analysis. The main conclusions are as follows: the Noah LSM performed well on the northern Tibetan Plateau. The simulated net radiation, upward longwave radiation, and upward shortwave radiation demonstrated the same remarkable annual and seasonal variation as the observed data, especially the upward longwave radiation. The simulated soil temperatures were acceptably close to the observed temperatures, especially in the shallow soil layers. The simulated freezing and melting processes were shown to start from the surface soil layer and spread down to the deep soil layers, but they took longer than the observed processes. However, Noah LSM did not adequately simulate the soil moisture. Therefore, additional high-quality, long-term observations of land surface-atmosphere processes over the Tibetan Plateau will be a key factor in proper adiustments of the model parameters in the future. 展开更多
关键词 Noah Land Surface Model off-line northern Tibetan Plateau radiation flux
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考虑公平关切的On/off-line供应链延保服务渠道策略研究 被引量:1
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作者 泮家丽 周兴建 +1 位作者 戴金山 季洪悦 《物流研究》 2022年第3期36-42,74,共8页
企业通过搭建线上线下(On/off-line)多渠道以满足消费者的延保服务需求,但也因此引发渠道间冲突。本文基于制造商视角搭建On/off-line延保服务渠道,引入公平关切理念,构建考虑零售商公平偏好的On/off-line延保服务决策模型,对延保服务... 企业通过搭建线上线下(On/off-line)多渠道以满足消费者的延保服务需求,但也因此引发渠道间冲突。本文基于制造商视角搭建On/off-line延保服务渠道,引入公平关切理念,构建考虑零售商公平偏好的On/off-line延保服务决策模型,对延保服务进行定价及利润分配,研究On/off-line渠道结构下的最优渠道策略。研究表明,当处于弱势地位的零售商存在公平关切偏好行为时,制造商可通过调整批发价以维护On/off-line渠道及供应链的稳定性;制造商增设线上渠道可增加自身利益,但会导致零售商利润降低;随着线上渠道的增设,公平关切程度的增加会降低零售商的效用。 展开更多
关键词 公平关切 渠道策略 供应链延保 线上线下
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Off-line Programming Technology Based on RPC Communication Method and its Application
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作者 王宏杰 Ding +6 位作者 Guoqing Yan Guozheng Zhu Honghai Lin Liangming 《High Technology Letters》 EI CAS 2001年第4期63-68,共6页
This paper puts forward a communication programming method between robot and external computer based on RPC (Remote Produce Call) communication method, which realizes robot distributed controlling network system model... This paper puts forward a communication programming method between robot and external computer based on RPC (Remote Produce Call) communication method, which realizes robot distributed controlling network system model. And a new Robot off line programming method is built based on this communication method and network model. Further more, as an example, robot auto marking and auto cutting of shipbuilding profile system is developed, which proves the ideas of author’s off line programming and development methods of robot flexible automation system. As a result, this paper presents a new method for developing robot flexible automation system. 展开更多
关键词 off line programming RPC communication Robot flexible automation Profile processing
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A word level segmentation for off-line Arabic characters
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作者 Abbas H +2 位作者 HASSIN 黄建华 唐降龙 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第4期391-396,共6页
Segmentation of cursive text has been one of the major problems in Arabic writing. The problem is the shape of the letter which is context sensitive, depending on it’s location within a word. Many text recognition sy... Segmentation of cursive text has been one of the major problems in Arabic writing. The problem is the shape of the letter which is context sensitive, depending on it’s location within a word. Many text recognition systems recognize text imagery at the character level and assemble words from the recognized characters. Unfortunately this approach does not work with Arabic text. In this paper we describe a new approach to segment Arabic text imagery at a word level, without analyzing individual characters. This approach avoids the problem of individual characters segmentation, and can overcome local errors in character recognition. 展开更多
关键词 OCR SEGMENTATION technique off-line RECOGNITION
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Off-line simulation of robot welding of radar pedestal
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作者 王丽七 CAO Guo-guang 《Journal of Chongqing University》 CAS 2017年第2期87-92,共6页
A study of the interference simulation based on robot welding of the radar pedestal was carried out by using the KUKA Sim Pro simulation software and off-line program technology. Compared with the actual robot welding... A study of the interference simulation based on robot welding of the radar pedestal was carried out by using the KUKA Sim Pro simulation software and off-line program technology. Compared with the actual robot welding process, it was found that the trajectory of the simulated robot welding process in line with that recorded in the actual welding process, and the actual limit and interference appeared at the same place as the simulation process. There was no interference phenomenon on the outside weld-seam; on the internal weld-seam, especially on the weld-joint of support plate connected to the cylinder, a phenomenon of interference appeared. It was helpful to use the simulation method to guide the actual robot welding so as to protect robot from impacting and reduce the weld defects. 展开更多
关键词 ROBOT WELDING off-line program INTERFERENCE simulation
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Study on path planning and compensation of off-line programming for thick walled curve welding
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作者 陈洪堂 李海超 +1 位作者 高洪明 吴林 《China Welding》 EI CAS 2015年第4期69-73,共5页
Thick walled curve welding are usually joined by multi-layer and multi-pass welding, which quality and efficiency could be improved by off-line programming of robot welding. However, the precision of off-line programm... Thick walled curve welding are usually joined by multi-layer and multi-pass welding, which quality and efficiency could be improved by off-line programming of robot welding. However, the precision of off-line programming welding path was decreased due to the deviation between the off-line planned welding path and the actual welding path. A path planning algorithm and a path compensation algorithm of multi-layer and multi-pass curve welding seam for off-line programming of robot welding are developed in this paper. Experimental results show that the robot off-line programming improves the welding efftcieney and precision for thick walled curve welding seam. 展开更多
关键词 robot welding off-line programming path planning path compensation
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Off-line Two-Dimensional Gas Chromatography-Mass Spectrometry for Analysis of Essential Oil of Medicinal Herb──Use of Absorption Trap
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作者 MA Xue-yi PAN Hui-ping and CHEN Yao-zu(iNational Laboratory of Applied Organic Cheniistry and Deparrmentof Chemistry, Lanzhou University, Lanzhou,7300007)(Department of Chemistry , Zhejiang Univer,ity, Hangzhou, 310027) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第4期291-296,共6页
he use of an absorption trap off-line two-dimensional gas chromatography (2-DGC) in conjunction with a mass spectrometer greatly improved the separation andidefitification of minor constituents of a complex mixture su... he use of an absorption trap off-line two-dimensional gas chromatography (2-DGC) in conjunction with a mass spectrometer greatly improved the separation andidefitification of minor constituents of a complex mixture such as a natural essentialoil. The absorption trap device used as an interface of 2-DGC offered the advantageof convenient manipulation. 展开更多
关键词 off-line two-dimensional gas chromatography Essential oil Absorp-tion trap Cymbopogon distans
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Image Motion Compensation of Off-Axis TMA Three-Line ArrayAerospace Mapping Cameras
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作者 Yongchang Li Pengluo Lu +2 位作者 Longxu Jin Guoning Li Yinan Wu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期80-89,共10页
To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. F... To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. Firstly,based on the imaging principle of mapping cameras,an analytical expression of image motion velocity of off-axis TMA three-line array aerospace mapping cameras is deduced from different coordinate systems we established and the attitude dynamics principle. Then,the case of a three-line array mapping camera is studied,in which the simulation of the focal plane image motion velocity fields of the forward-view camera,the nadir-view camera and the backward-view camera are carried out,and the optimization schemes for image motion velocity matching and drift angle matching are formulated according the simulation results. Finally,this method is verified with a dynamic imaging experimental system. The results are indicative of that when image motion compensation for nadir-view camera is conducted using the proposed image motion velocity field model,the line pair of target images at Nyquist frequency is clear and distinguishable. Under the constraint that modulation transfer function( MTF) reduces by 5%,when the horizontal frequencies of the forward-view camera and the backward-view camera are adjusted uniformly according to the proposed image motion velocity matching scheme,the time delay integration( TDI) stages reach 6 at most. When the TDI stages are more than 6,the three groups of camera will independently undergo horizontal frequency adjustment. However, when the proposed drift angle matching scheme is adopted for uniform drift angle adjustment,the number of TDI stages will not exceed 81. The experimental results have demonstrated the validity and accuracy of the proposed image motion velocity field model and matching optimization scheme,providing reliable basis for on-orbit image motion compensation of aerospace mapping cameras. 展开更多
关键词 three-line array mapping camera off-axis TMA image motion compensation image motion velocity drift angle
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Disparity-Based Generation of Line-of-Sight DSM for Image-Elevation Co-Registration to Support Building Detection in Off-Nadir VHR Satellite Images 被引量:1
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作者 Alaeldin Suliman Yun Zhang 《Journal of Geographic Information System》 2018年第1期25-56,共32页
The integration of optical images and elevation data is of great importance for 3D-assisted mapping applications. Very high resolution (VHR) satellite images provide ideal geo-data for mapping building information. Si... The integration of optical images and elevation data is of great importance for 3D-assisted mapping applications. Very high resolution (VHR) satellite images provide ideal geo-data for mapping building information. Since buildings are inherently elevated objects, these images need to be co-registered with their elevation data for reliable building detection results. However, accurate co-registration is extremely difficult for off-nadir VHR images acquired over dense urban areas. Therefore, this research proposes a Disparity-Based Elevation Co-Registration (DECR) method for generating a Line-of-Sight Digital Surface Model (LoS-DSM) to efficiently achieve image-elevation data co-registration with pixel-level accuracy. Relative to the traditional photogrammetric approach, the RMSE value of the derived elevations is found to be less than 2 pixels. The applicability of the DECR method is demonstrated through elevation-based building detection (EBD) in a challenging dense urban area. The quality of the detection result is found to be more than 90%. Additionally, the detected objects were geo-referenced successfully to their correct ground locations to allow direct integration with other maps. In comparison to the original LoS-DSM development algorithm, the DECR algorithm is more efficient by reducing the calculation steps, preserving the co-registration accuracy, and minimizing the need for elevation normalization in dense urban areas. 展开更多
关键词 Stereo VHR Satellite Images off-Nadir Images DISPARITY Maps ELEVATION Data CO-REGISTRATION Building Detection line-OF-SIGHT DSM
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KUKA Officelite在模具激光熔覆中的应用 被引量:2
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作者 孟小鑫 张德强 李金华 《机械设计与制造》 北大核心 2014年第5期240-242,共3页
逆向工程技术和激光熔覆技术在模具修复中有着很关键的作用,用逆向工程技术对破损模具进行逆向造型,通过对比求差提取出模具的磨破损区域,对磨破损区域分析后的修复轨迹生成主要有手工编程和离线编程两种,手工编程效率低,精度低,离线编... 逆向工程技术和激光熔覆技术在模具修复中有着很关键的作用,用逆向工程技术对破损模具进行逆向造型,通过对比求差提取出模具的磨破损区域,对磨破损区域分析后的修复轨迹生成主要有手工编程和离线编程两种,手工编程效率低,精度低,离线编程的优势明显。KUKA Officelite软件为KUKA机器人离线编程软件,其作用是将KUKA机器人仿真模拟软件KUKA SimPro2.2所设计的路径轨迹程序自动编译成机械手可执行的程序。因此KUKA Officelite软件的应用能使激光熔覆的编程变得简单。通过一个模具激光熔覆实例,证明了KUKA Officelite软件的使用显著提高了编程的效率,简化了激光熔覆的过程。 展开更多
关键词 KUKA officelite KUKA SimPr02 2 激光熔覆 离线编程
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Tet-off调控bcr/abl基因表达的细胞系293pT2-P210的建立
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作者 黄文荣 鲁茁壮 +5 位作者 王立生 王华 段海峰 李庆芳 高春记 达万明 《中国实验血液学杂志》 CAS CSCD 2007年第2期224-228,共5页
慢性髓系白血病(CML)是一种以髓系细胞受累为主的克隆性疾病。目前认为CML的主要分子发病基础为:位于9q34的abl基因与位于22q11的bcr基因相互易位形成bcr/abl融合基因,并编码具有很强蛋白酪氨酸激酶活性的P210bcr/abl融合蛋白,该蛋白通... 慢性髓系白血病(CML)是一种以髓系细胞受累为主的克隆性疾病。目前认为CML的主要分子发病基础为:位于9q34的abl基因与位于22q11的bcr基因相互易位形成bcr/abl融合基因,并编码具有很强蛋白酪氨酸激酶活性的P210bcr/abl融合蛋白,该蛋白通过多种信号通路抑制细胞凋亡而导致细胞转化。本研究为构建能由Tet-off诱导表达系统调控bcr/abl融合基因表达的细胞系,为深入研究bcr/abl融合基因功能及其调控机制提供一种有价值的细胞模型。将bcr/abl融合基因亚克隆到pTRE2hyg载体构建重组质粒pT2-P210,同时将Tet-off质粒转染293细胞并筛选出单克隆,然后进一步转染pTRE2hyg-LUC质粒,通过荧光素酶活性检测选出能有效诱导目的基因表达的293Tet-off细胞,然后将重组质粒pT2-P210转染到293Tet-off细胞中。结果表明:筛选出了bcr/abl融合基因能被强力霉素有效调控的293pT2-P210单克隆细胞。结论:本研究筛选的293pT2-P210细胞为bcr/abl基因表达能被Tet-off诱导表达系统调控的细胞系,它们适用于bcr/abl融合基因功能及其信号调控机制的深入研究。 展开更多
关键词 BCR/ABL融合基因 Tet-off诱导表达系统 293pT2-P210细胞系 293细胞
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Tet-off诱导表达Egr-1HEK293稳定细胞株的建立和鉴定 被引量:1
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作者 彭琬昕 孟凡力 +1 位作者 金洁 龚爱华 《江苏大学学报(医学版)》 CAS 2014年第2期118-121,共4页
目的:利用大肠埃希菌Tet-off诱导表达调控系统构建多西环素调控的稳定细胞株。方法:以pEGFPEgr-1质粒为模板,扩增含早期生长反应蛋白(early growth response-1,Egr-1)完整开放阅读框的DNA序列,经酶切后插入含四环素反应元件(tetracyclin... 目的:利用大肠埃希菌Tet-off诱导表达调控系统构建多西环素调控的稳定细胞株。方法:以pEGFPEgr-1质粒为模板,扩增含早期生长反应蛋白(early growth response-1,Egr-1)完整开放阅读框的DNA序列,经酶切后插入含四环素反应元件(tetracycline responsive element,TRE)序列的表达载体pTRE2hyg,获得重组质粒pTRE2hyg-Egr-1,将其转染293Tet-off细胞株,并用G418和多西环素筛选稳定表达Egr-1的细胞株。蛋白质印迹法检测多西环素诱导表达Egr-1情况;流式细胞术检测细胞增殖能力。结果:蛋白质印迹结果显示,外源性Egr-1蛋白表达受细胞培养液中多西环素调控,当从细胞培养液中去除多西环素后,Egr-1表达量明显升高。流式细胞检测结果显示Egr-1高表达细胞的增殖能力明显高于Egr-1低表达细胞。结论:利用Tet-off体系成功构建Egr-1诱导表达的细胞株,细胞的增殖能力受Egr-1表达水平的影响。 展开更多
关键词 Tet-off调控系统 早期生长反应蛋白1 稳定细胞株 多西环素
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