期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
RapidEye影像正射影像图生产工艺探讨 被引量:2
1
作者 熊德科 尹峰 李荆荆 《地理空间信息》 2011年第3期89-91,189,共3页
介绍了在正射影像生产中一些关键环节,如用Photoshop对有薄云的RapidEye影像进行去薄云融合处理;对山区影像用小面元微分纠正等。总结了针对RapidEye影像去薄云和山区纠正困难的一套快速有效生产工艺。
关键词 rapideye 通道 色阶 纠正
下载PDF
Fast Scheme for Projective Geometric Correction and Edge Blending Based on High Dynamic Range Images
2
作者 柳喆俊 金云水 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期214-218,共5页
With the development of graphic processing unit(GPU)power,it is now possible to implement geometric correction and edge blending functions on a single computer.However,the processing resources consumed by the geometri... With the development of graphic processing unit(GPU)power,it is now possible to implement geometric correction and edge blending functions on a single computer.However,the processing resources consumed by the geometric correction and edge blending phases still burden the system and slow down the main application considerably.A new platform independent scheme is proposed,minimizing the negative influence on performance.In this scheme,parameters for geometric correction and edge blending are firstly defined in an interactive way and recorded as a 32-bit high dynamic range(HDR) image,which is then used by high level shading language(HLSL) codes embedded in the main application as a lookup table,greatly reducing the computational complexity and enhancing flexibility. 展开更多
关键词 correction blending interactive pixel projection minimizing burden overlapping flexibility rendering
下载PDF
Glacial Isostasy:Regional—Not Global
3
作者 Nils-Axel Morner 《International Journal of Geosciences》 2015年第6期577-592,共16页
The load of the continental ice caps of the Ice Ages deformed the bedrock, and when the ice melted in postglacial time, land rose. This process is known as glacial isostasy. The deformations are compensated either reg... The load of the continental ice caps of the Ice Ages deformed the bedrock, and when the ice melted in postglacial time, land rose. This process is known as glacial isostasy. The deformations are compensated either regionally or globally. Fennoscandian data indicate a regional compensation. Global sea level data support a regional, not global, compensation. Subtracting GIA corrections from satellite altimetry records brings—for the first time—different sea level indications into harmony of a present mean global sea level rise of 0.0 to 1.0 mm/yr. 展开更多
关键词 Glacial Isostasy FENNOSCANDIA Postglacial Uplift Uplift Cone Subsidences Trough Forebulge Low Viscosity channel Flow Global Sea Level Data correcting Satellite Altimetry Removing Global GIA correction
下载PDF
Water level updating model for flow calculation of river networks
4
作者 Xiao-ling WU Xiao-hua XIANG +1 位作者 Li LI Chuan-hai WANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期60-69,共10页
Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up base... Complex water movement and insufficient observation stations are the unfavorable factors in improving the accuracy of flow calculation of river networks. A water level updating model for river networks was set up based on a three-step method at key nodes, and model correction values were collected from gauge stations. To improve the accuracy of water level and discharge forecasts for the entire network, the discrete coefficients of the Saint-Venant equations for river sections were regarded as the media carrying the correction values from observation locations to other cross-sections of the river network system. To examine the applicability, the updating model was applied to flow calculation of an ideal river network and the Chengtong section of the Yangtze River. Comparison of the forecast results with the observed data demonstrates that this updating model can improve the forecast accuracy in both ideal and real river networks. 展开更多
关键词 plain river network cyclic looped channel network water level updating model hydrodynamic model error correction
下载PDF
自记水位条件下河道径流演进分析技术及应用
5
作者 王育杰 刘合永 +2 位作者 罗勐 孟先新 娄书建 《人民黄河》 CAS 北大核心 2018年第1期15-17,22,共4页
依靠现代信息技术对我国现阶段河道遥测水位设施设备进行了高效继承,对遥测系统与径流演进预报应用进行了深度融合。实践表明:不同地域、不同网络环境、不同终端、不同浏览器用户能够全天候实时监测河道水位、流量变化及径流演进传播等... 依靠现代信息技术对我国现阶段河道遥测水位设施设备进行了高效继承,对遥测系统与径流演进预报应用进行了深度融合。实践表明:不同地域、不同网络环境、不同终端、不同浏览器用户能够全天候实时监测河道水位、流量变化及径流演进传播等,实现了高度的自动化与实时性,并且具备自动跟进校正特点,运行可靠稳定,实用性强。 展开更多
关键词 径流演进 自动校正 遥测水位 河道
下载PDF
实时视频传输的帧级别前向纠错信道编码 被引量:4
6
作者 柳粟杰 杨秀芝 +1 位作者 陈平平 王琳 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第6期964-971,共8页
针对5G通信中低时延、高可靠传输需求,在视频编码传输系统中,给定传输带宽的条件下,提出了视频帧级别的应用层前向纠错(FEC)信道编码的优化方案.联合考虑视频有损压缩失真和信道丢包,选取量化参数(QP)和视频帧FEC码率,优化压缩和FEC编... 针对5G通信中低时延、高可靠传输需求,在视频编码传输系统中,给定传输带宽的条件下,提出了视频帧级别的应用层前向纠错(FEC)信道编码的优化方案.联合考虑视频有损压缩失真和信道丢包,选取量化参数(QP)和视频帧FEC码率,优化压缩和FEC编码的冗余分配,改进视频重构效果.又因视频重构图像组(GOP)中,帧内编码(I帧)和靠近它的帧间编码(P帧)具有相似的重要性,所以在给定QP后进一步提出帧级别的动态FEC方案,动态分配I帧和P帧的冗余.随机丢包的仿真传输系统结果表明:1)QP分别为25,30和40时,视频重构在QP为30时效果最好;2)当QP为30,丢包率(PLR)为5%时,相比于传统FEC方案,帧间动态FEC方案可有效提高视频峰值信噪比(PSNR);3)在实际高清需求中通过端到端传输的5G远程驾驶,表明所提出的动态FEC方案可保证路况视频的实时传输. 展开更多
关键词 视频传输 5G通信 帧级别信道编码 前向纠错
下载PDF
单向信道的信息可靠传输机制研究 被引量:2
7
作者 曹震 孙德刚 +2 位作者 史林港 唐碧华 谢刚 《计算机工程与应用》 CSCD 北大核心 2011年第24期88-92,共5页
提出了两级FEC的机制来解决单向信道的信息可靠传输的问题。数据包级FEC(第一级)通过添加冗余数据包来恢复传输过程中数据包的丢失。比特级FEC(第二级)通过添加冗余比特来纠正数据在传输过程中比特差错。鉴于包头信息是数据包级FEC的关... 提出了两级FEC的机制来解决单向信道的信息可靠传输的问题。数据包级FEC(第一级)通过添加冗余数据包来恢复传输过程中数据包的丢失。比特级FEC(第二级)通过添加冗余比特来纠正数据在传输过程中比特差错。鉴于包头信息是数据包级FEC的关键,提出数据包包头FEC机制来尽量保证包头信息的正确。提出的方案能很好地恢复丢失的数据包,特别是连续数据包的丢失,能很好地纠正比特差错。 展开更多
关键词 单向信道 数据包级前向纠错 比特级前向纠错
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部