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镉对小白菜光合作用特性影响的研究 被引量:37
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作者 李德明 朱祝军 +1 位作者 刘永华 王玉清 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2005年第4期459-464,共6页
研究表明,微量镉(Cd)(0.01、0.1 mg/L)促进小白菜(Brassica campestris ssp.chinensis)生长,对苏州青的促进作用更明显;高浓度Cd显著抑制地上部生长,对根系生长影响相对较小.Cd降低小白菜叶绿素含量,特别是苏州青降低幅度较大.低浓度Cd... 研究表明,微量镉(Cd)(0.01、0.1 mg/L)促进小白菜(Brassica campestris ssp.chinensis)生长,对苏州青的促进作用更明显;高浓度Cd显著抑制地上部生长,对根系生长影响相对较小.Cd降低小白菜叶绿素含量,特别是苏州青降低幅度较大.低浓度Cd对小白菜净光合速率Pn影响不大,高浓度Cd可能是由于非气孔限制而引起Pn降低.Cd降低气孔导度,但高浓度Cd增加胞间CO2浓度.叶绿素荧光测定表明,Cd对小白菜叶片光化学效率Fv/Fm影响不大,而高浓度Cd明显降低光合电子传递量子效率PSⅡ、光化学淬灭系数qP和电子传递速率ETR.Cd增加沪青一号非光化学淬灭系数qNP,而苏州青在高Cd浓度下qNP下降. 展开更多
关键词 小白菜(Brassica CAMPESTRIS ssp.chinensis) 光合作用 叶绿素荧光
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罗寄梅拍摄敦煌石窟照片的意义 被引量:8
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作者 赵声良 《敦煌研究》 CSSCI 北大核心 2014年第3期79-91,共13页
1943—1944年在敦煌艺术研究所创办之初,曾聘请摄影师罗寄梅到敦煌拍摄了大部分洞窟的内容,由于各种原因,这些多达2000多张的照片至今未公开出版。现介绍收藏在普林斯顿大学的罗寄梅敦煌石窟照片的主要内容,并从洞窟外观历史及洞窟内部... 1943—1944年在敦煌艺术研究所创办之初,曾聘请摄影师罗寄梅到敦煌拍摄了大部分洞窟的内容,由于各种原因,这些多达2000多张的照片至今未公开出版。现介绍收藏在普林斯顿大学的罗寄梅敦煌石窟照片的主要内容,并从洞窟外观历史及洞窟内部资料两个方面说明罗氏敦煌照片的意义和价值。 展开更多
关键词 敦煌石窟 罗寄梅 照片 历史
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Building a model-based personalised recommendation approach for tourist attractions from geotagged social media data 被引量:7
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作者 Xiaoyu Sun Zhou Huang +2 位作者 Xia Peng Yiran Chen Yu Liu 《International Journal of Digital Earth》 SCIE EI 2019年第6期661-678,共18页
When travelling,people are accustomed to taking and uploading photos on social media websites,which has led to the accumulation of huge numbers of geotagged photos.Combined with multisource information(e.g.weather,tra... When travelling,people are accustomed to taking and uploading photos on social media websites,which has led to the accumulation of huge numbers of geotagged photos.Combined with multisource information(e.g.weather,transportation,or textual information),these geotagged photos could help us in constructing user preference profiles at a high level of detail.Therefore,using these geotagged photos,we built a personalised recommendation system to provide attraction recommendations that match a user’s preferences.Specifically,we retrieved a geotagged photo collection from the public API for Flickr(Flickr.com)and fetched a large amount of other contextual information to rebuild a user’s travel history.We then created a model-based recommendation method with a two-stage architecture that consists of candidate generation(the matching process)and candidate ranking.In the matching process,we used a support vector machine model that was modified for multiclass classification to generate the candidate list.In addition,we used a gradient boosting regression tree to score each candidate and rerank the list.Finally,we evaluated our recommendation results with respect to accuracy and ranking ability.Compared with widely used memory-based methods,our proposed method performs significantly better in the cold-start situation and when mining‘long-tail’data. 展开更多
关键词 Recommendation system geotagged photos social media model-based approach support vector machine(SVM) gradient boosting regression tree(GBRT)
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Long-term vegetation development on a wildfire slope in Innerzwain(Styria,Austria) 被引量:4
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作者 Bodo Malowerschnig Oliver Sass 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期103-111,共9页
Forest fires in mountainous areas can cause severe defores-tation which can potentially trigger secondary natural hazards like debris falls and avalanches. We documented an extreme case study for the range of possible... Forest fires in mountainous areas can cause severe defores-tation which can potentially trigger secondary natural hazards like debris falls and avalanches. We documented an extreme case study for the range of possible post-fire land cover (LC) dynamics. We investigated a 15-ha, steep (10°-65°) burnt slope in Styria (Austria) at elevation of 760-1130 m, which burned in 1946 and has not fully recovered to date. Seven 8-class legend LC maps were produced (1954, 1966, 1973, 1982, 1998, 2004, 2009) and integrated in a vector-based GIS, mainly by on-screen interpretation of aerial photos. Our aim was to clarify how post-wildfire LC dynamics take place on a severely damaged, steep slope and to give a basic projection of the future vegetation recovery process. The pre-fire Pinus sylvestrisstands have been mainly replaced by Picea abies and Larix decidua. Regeneration proceeded mainly from the base of the slope upwards. All tree species together still cover no more than 40% of the slope after more than 60 years of recovery, while grassland communities and rock/debris areas have expanded. Multitemporal analysis showed a slow but steady increase in woodland cover. Degraded rock/debris areas, however, expanded as well because soil erosion and related debris flows remained active. Slope angle (with a threshold value of approx. 35-40°) seemed to control whether erosion or regeneration prevailed. According to a simple extrapolation, the slope will not reach its former condition before 2070. This extreme disturbance window of more than 120 years is owed to the steepness of the slope and to the shallow soils on dolomitic bedrock that were severely damaged by the fire. The neglect of any game fencing is a further factor slowing regeneration. 展开更多
关键词 WILDFIRE landcover change temperate forest aerial photos soil degradation vegetation development
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神经网络在老照片修复中的应用
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作者 杨庆庆 卓树峰 +2 位作者 魏丽芬 陈岳林 郑静宜 《福建电脑》 2024年第4期45-48,共4页
随着电子相机和扫描仪的普及,老旧照片可以进行数字化处理后再进行手工修复。修复照片时,用手工提取照片特征的方法既费力又耗时,难以满足对海量老旧照片的恢复需求。为解决这个问题,本文提出了一个基于注意力机制的老旧照片修复方法。... 随着电子相机和扫描仪的普及,老旧照片可以进行数字化处理后再进行手工修复。修复照片时,用手工提取照片特征的方法既费力又耗时,难以满足对海量老旧照片的恢复需求。为解决这个问题,本文提出了一个基于注意力机制的老旧照片修复方法。该方法不仅通过神经网络强大的表征能力学习特定任务的映射,还将注意力机制和知识蒸馏引入老旧照片修复网络的框架中。试验结果表明,所提出的方法能够在修补图像纹理结构区域时获得真实自然的修复结果,显著提高严重退化的旧照片的视觉效果。 展开更多
关键词 照片 图像修复 机器视觉 神经网络
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在线照片打印平台的设计与实现
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作者 坎香 《福建电脑》 2024年第3期113-116,共4页
为更好地服务于用户,保证用户打印照片的需求得到及时响应,本文设计并开发了一款在线照片打印平台。平台使用ThinkPHP技术开发及MySQL设计数据库,实现了照片打印服务的全程管理。该平台可以便捷、高效地完成打印照片任务,避免了人工管... 为更好地服务于用户,保证用户打印照片的需求得到及时响应,本文设计并开发了一款在线照片打印平台。平台使用ThinkPHP技术开发及MySQL设计数据库,实现了照片打印服务的全程管理。该平台可以便捷、高效地完成打印照片任务,避免了人工管理带来的遗漏和不足,实现了照片打印的系统化和规范化。 展开更多
关键词 照片 在线打印 ThinkPHP技术 管理平台
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故宫博物院藏清末新军影像评述
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作者 杨国彭 《保定学院学报》 2024年第1期41-48,共8页
故宫博物院藏有清末新军相册12部共800余张影像,这是目前海内外数量最多的一批新军主题照片。其拍摄时间从1905年持续到1910年,内容分为校阅和秋操两大类。影像呈现了当时新军将领、武器、服制、训练及演习等真实画面,是清末新军编练成... 故宫博物院藏有清末新军相册12部共800余张影像,这是目前海内外数量最多的一批新军主题照片。其拍摄时间从1905年持续到1910年,内容分为校阅和秋操两大类。影像呈现了当时新军将领、武器、服制、训练及演习等真实画面,是清末新军编练成果的直观展示。 展开更多
关键词 清末 北洋新军 影像 故宫博物院
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硬质合金金相图谱的制作 被引量:3
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作者 钟奇志 《硬质合金》 CAS 北大核心 2006年第4期231-234,共4页
简述了硬质合金的金相图谱的制作过程,介绍了制作过程中重点问题的解决办法,以及制作的金相图谱的特点。该整套图谱对现有的金相检测图谱是一个非常丰富的补充,具有重要的实用意义。
关键词 硬质合金 金相 图谱 金相检测 彩色图谱
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基于照片的人脸三维建模 被引量:3
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作者 张九龙 胡正国 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第5期385-386,389,共3页
研究由一张正面照片和一张侧面照片合成头部三维模型的自动方法。从照片中提取面部特征点后 ,修改基本模型生成特定人的面部三维模型。从两张照片可以合成任意角度视图 。
关键词 面部建模 基本模型 模型修改 纹理映射 照片 面部特征 计算机图形学
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Agisoft Photoscan多视点3D建模技术在校园虚拟漫游中的应用 被引量:4
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作者 李波 《信息与电脑》 2019年第6期115-116,共2页
校园虚拟漫游系统场景创建过程中,针对虚拟地形和复杂景观建模所遇到的地形面积大、形态复杂、建模工作效率低等问题,笔者在VR校园部分模型构建中使用AgisoftPhotoscan多视点3D建模技术。相比传统的三维建模软件,AgisoftPhotoscan软件... 校园虚拟漫游系统场景创建过程中,针对虚拟地形和复杂景观建模所遇到的地形面积大、形态复杂、建模工作效率低等问题,笔者在VR校园部分模型构建中使用AgisoftPhotoscan多视点3D建模技术。相比传统的三维建模软件,AgisoftPhotoscan软件易上手、简单,数据收集快速、高效,能快速自动完成3D模型构建。以郑州工业应用技术学院所建立的校园虚拟漫游系统为例,介绍Agisoft Photoscan多视点三维建模技术的方法和流程。 展开更多
关键词 校园虚拟漫游 快速建模 多视点 照片
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PP-GAN:Style Transfer from Korean Portraits to ID Photos Using Landmark Extractor with GAN
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作者 Jongwook Si Sungyoung Kim 《Computers, Materials & Continua》 SCIE EI 2023年第12期3119-3138,共20页
The objective of style transfer is to maintain the content of an image while transferring the style of another image.However,conventional methods face challenges in preserving facial features,especially in Korean port... The objective of style transfer is to maintain the content of an image while transferring the style of another image.However,conventional methods face challenges in preserving facial features,especially in Korean portraits where elements like the“Gat”(a traditional Korean hat)are prevalent.This paper proposes a deep learning network designed to perform style transfer that includes the“Gat”while preserving the identity of the face.Unlike traditional style transfer techniques,the proposed method aims to preserve the texture,attire,and the“Gat”in the style image by employing image sharpening and face landmark,with the GAN.The color,texture,and intensity were extracted differently based on the characteristics of each block and layer of the pre-trained VGG-16,and only the necessary elements during training were preserved using a facial landmark mask.The head area was presented using the eyebrow area to transfer the“Gat”.Furthermore,the identity of the face was retained,and style correlation was considered based on the Gram matrix.To evaluate performance,we introduced a metric using PSNR and SSIM,with an emphasis on median values through new weightings for style transfer in Korean portraits.Additionally,we have conducted a survey that evaluated the content,style,and naturalness of the transferred results,and based on the assessment,we can confidently conclude that our method to maintain the integrity of content surpasses the previous research.Our approach,enriched by landmarks preservation and diverse loss functions,including those related to“Gat”,outperformed previous researches in facial identity preservation. 展开更多
关键词 Style transfer style synthesis generative adversarial network(GAN) landmark extractor ID photos Korean portrait
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Analyzing Land Cover Change—The Impact of the Motorway Construction and Their Operation on Landscape Structure 被引量:1
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作者 Zdenek Keken Marika Sebkova Jan Skalos 《Journal of Geographic Information System》 2014年第5期559-571,共13页
The aim of our study was to assess the influence of motorways on landscape structure changes. The research was situated on segments of the D1 and D3 motorways in the Czech Republic. The method used for determining the... The aim of our study was to assess the influence of motorways on landscape structure changes. The research was situated on segments of the D1 and D3 motorways in the Czech Republic. The method used for determining the impacts of the construction and operation of the motorway on the landscape structure was based on comparing the development of the land cover types in an area where the motorway was present for almost the entire monitored period (D1 motorway segment) with the development of the land cover types in an area where the motorway was constructed towards the end of the monitored period (D3 motorway segment). Monitored period?was?between years 1949, 1988 (1984 segment of motorway D3) and 2007. Source materials were processed and analyzed in the ArcGIS software environment. Our comparison indicated that the main differences between segments were in the level of development of commercial, industrial and agricultural built-up area in the vicinity of motorways. The existence of the motorway also contributed to the development of residential areas. It should be noted that in both cases there was also an increase in the extension?of shrubs and scattered vegetation, and in small quantities also category of forest. 展开更多
关键词 LAND Use Landscape Development AERIAL photos Commercial SUBURBANIZATION LAND OCCUPATION
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Regional difference and dynamic mechanism of locality of the Chinese farming-pastoral ecotone based on geotagged photos from Panoramio 被引量:1
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作者 WANG Fang LI Yixi +1 位作者 DONG Ying ZHU Xiaohua 《Journal of Arid Land》 SCIE CSCD 2018年第2期316-333,共18页
Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-p... Cross-regional locality research reflects the influences of natural environment and the human activities due to the abundant land types and the multiple landscape combinations in related regions. The Chinese farming-pastoral ecotone is a typical large-scale region but few studies were conducted. This research contributed to the understanding of cross-regional locality of the Chinese farming-pastoral ecotone from different scales, including national, sectional, and provincial administrative units by utilizing geotagged photos(GTPs) obtained from the Panoramio website. The major results were as follows:(1) the locality elements of the Chinese farming-pastoral ecotone included 52 free nodes classified into 8 types of scene attributes;(2) there were huge differences between locality elements of different regions, and there was a negative correlation between the similarity degree of elements of different provinces and their spatial distances;(3) the Chinese farming-pastoral ecotone could be divided into the northern, central and southern sections, whose localities had differences in element constitution, association structure and the strength of elements, system stability and the anti-interference capability; and(4) the evolution of the localities of the northern and central sections was mainly influenced by human activities, while the locality of southern section retained more natural features. On a theoretical level, this research aimed to establish the research methodology of locality from the perspective of open data on the web with strong operability and replicability. On a practical level, this research could enrich the structuring recognition of the locality of the Chinese farming-pastoral ecotone and the comprehension of its dynamic mechanism. The results provide a reference for locality differentiation protection and the development of a cross-regional scale. 展开更多
关键词 administrative units geotagged photos LANDSCAPE LOCALITY NETWORKS regional differences
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图像媒介下鲁迅的形象塑造及文学观念嬗变 被引量:2
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作者 黄乔生 《中国文学研究》 CSSCI 北大核心 2022年第3期121-128,163,共9页
鲁迅有过长期的照相经历,并对照相术做过系统思考,形成了独特的图像观念,他视图像为促进文学传播和交流的重要手段,并在写作中自觉融入了“照相”方法,晚年甚至尝试“立此存照”的写作方式。鲁迅的公众形象塑造借助图像媒介获得了独特... 鲁迅有过长期的照相经历,并对照相术做过系统思考,形成了独特的图像观念,他视图像为促进文学传播和交流的重要手段,并在写作中自觉融入了“照相”方法,晚年甚至尝试“立此存照”的写作方式。鲁迅的公众形象塑造借助图像媒介获得了独特表达效果,但他对照相这一现代技术的态度有着从热到冷的变化过程,晚年对包括照相在内的现代影像技术及其与自己的写作方法之间的关系进行了审视和反思。本文分析图像媒介下鲁迅形象的自塑和他塑过程,揭示鲁迅图像观念的变化以及这种变化对其文学观念的影响。 展开更多
关键词 鲁迅 照片 形象塑造 文学观念
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A Multi-Resolution Photogrammetric Framework for Digital Geometric Recording of Large Archeological Sites: Ajloun Castle-Jordan 被引量:1
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作者 A’kif Al-Fugara Rida Al-Adamat +2 位作者 Yahya Al-Shawabkeh Omar Al-Kour Abdel Rahman Al-Shabeeb 《International Journal of Geosciences》 2016年第3期425-439,共15页
The generation of reality-based 3D models of archeological sites is the future of representing existing ancient structures. Such approach requires substantial economic and logistical costs which limit this application... The generation of reality-based 3D models of archeological sites is the future of representing existing ancient structures. Such approach requires substantial economic and logistical costs which limit this application. In this context, this paper presents the use of photogrammetric workflow, based on Structure from Motion techniques (SfM) to derive 3D metric information from Structure-and-Motion images. The interdisciplinary 3D modeling framework consists of fusion of multi resolution images from both overlapped low-altitude aerial and multi-view terrestrial imagery. The acquisition of aerial photographs survey was based on archived oblique aerial stereo pair photos acquired from the Aerial Photographic Archive for Archaeology in the Middle East (APAAME) project, while terrestrial of close range photos covering the castle walls has been acquired using portable camera. Camera calibration and orientation were carried out by VisualSFM, CMPMVS (Multi-View Reconstruction) and SURE (Photogrammetric Surface Reconstruction from Imagery) software. The resulted cloud points were processed using cloud Compare, MeshLab, Agisoft, and Skethup Softwares. A complete 3D digital geometric recording of the site was accomplished based on dense 3D point clouds with realistic metric accuracy and photorealistic performance to meet all the surveying and archaeological needs. The final Ajloun castle’s digital model geometry was added as a 3D building layer on Google Earth. 展开更多
关键词 Ajloun Castle 3D Modeling SFM Terrestrial Images Aerial photos Archaeological Documentation photoGRAMMETRY
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试探归档照片真伪鉴定方法 被引量:3
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作者 王凤刚 《山西档案》 北大核心 2006年第1期33-34,共2页
关键词 归档照片 真伪鉴定 鉴定方法 档案文献 数码照片
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Impact of Rapid Urbanization and Changing Housing Patterns on Urban Open Public Spaces of Amman, Jordan: A GIS and RS Perspective
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作者 Yahya Farhan Sireen Al-Shawamreh 《Journal of Environmental Protection》 2019年第1期57-79,共23页
Rapid urbanization and population growth of the Amman Area were combined with land resource degradation when the city was heading for mounting urbanization from the early 1950s. The deterioration of natural resources ... Rapid urbanization and population growth of the Amman Area were combined with land resource degradation when the city was heading for mounting urbanization from the early 1950s. The deterioration of natural resources and green areas, was coupled with the creation of different urban public open spaces in the city. The transformation from large single-family houses to dense residential apartments was associated with social and behavioral changes among the inhabitants living in the dense apartments. Consequently, a large private sector has been developed to provide public and social spaces. Photo-interpretation and satellite images were used to map and characterize land use/cover changes have been occurred in the Amman area between 1953 and 2017. Maximum Likelihood Classification method was employed to identify land use/cover changes between 1986 and 20017, and GIS was utilized also to map examples of the recently emerged socio-economic open spaces. Excessive urban development in the last two decades, and the adoption of neo-liberal privatization policies by the government, enhanced social stratification and residential segregation. So, instead of encouraging outdoor activity and social interaction among all groups of Amman residents, the freedom of accessibility to major open spaces has been restricted within the same urban fabric, thus, the “two Ammans” paradigm, a “tale of two cities”, has been recently acknowledged. 展开更多
关键词 URBAN Public SPACE PRIVATE SPACE Landsat Images Air photos Land Use/Cover Amman
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Comparison and Validation of the Recent Freely Available DEMs over Parts of the Earth’s Lowest Elevation Area: Dead Sea, Jordan
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作者 A’kif Al-Fugara 《International Journal of Geosciences》 2015年第11期1221-1232,共12页
The present research study assesses the accuracy of two recent freely available ASTER-GDEM ver.2, SRTM ver.4.1 digital elevation models for parts of the lowest area on the earth on the shores of the Dead Sea, the site... The present research study assesses the accuracy of two recent freely available ASTER-GDEM ver.2, SRTM ver.4.1 digital elevation models for parts of the lowest area on the earth on the shores of the Dead Sea, the site located over areas with high variation in topography within the “humratessahan” watershed, where the elevation varies between 700 m above sea level in the north east of the watershed to 210 meter below sea level. The reference elevation data used in this study are topographical points extracted from existing digital vector topographical map published by Royal Jordanian Geographical Center (RJGC). However, the contour lines do not cover the whole area especially in the flat areas where elevation is less than the contour line interval. Therefore, the second reference data created with photogrammetric techniques from stereoscopic pairs of aerial photos had been used for the surface to surface comparison and elevation profiles assessment purpose. It is demonstrated that the vertical accuracy of ASTER-GDEM ver.2 is 22.223 m (Root Mean Square Error (RMSE)) against reference elevation data, while the SRTM ver.4.1 has an RMSE of 15.858 m;the statistics results indicate that the theoretical accuracy is achievable and meets the expected accuracy specification. Furthermore, as for its unprecedented detail, it is believed that the photogrammetric derived DEM offers an alternative in accessibility to high-quality elevation data with vertical accuracy of 0.78 m (Root Mean Square Error (RMSE)). 展开更多
关键词 ASTER-GDEM ver.2 SRTM ver.4.1 Aerial photos Vertical Accuracy DEAD Sea
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照片档案的电子化管理探析 被引量:2
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作者 王爱芹 《晋城职业技术学院学报》 2009年第6期58-59,共2页
照片档案是档案的重要组成部分,但收集与整理一直是一大难题。现代信息技术的发展,为更好地发挥照片存史资政育人的功能,提供了一个难得的平台。本文着重就照片档案的电子化管理做了一些探讨,以期为方面的应用和管理提供思路。
关键词 照片 档案 电子管理
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Photons, Fibres and Defence
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作者 W.A.Gambling Manuscript received (Director, Optoelectronics Research, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 1999年第1期1-6,共6页
Becare of their low transmission loss, large bandwidth and small size, silica optical fibres have revolutionised telecommunications. Applications in other fields have been more limited. However, they are being increas... Becare of their low transmission loss, large bandwidth and small size, silica optical fibres have revolutionised telecommunications. Applications in other fields have been more limited. However, they are being increasingly used in military systems where their additional advantages of light weight, ruggedness, flexibility high strength and freedom electromagnetic interference can be erectal. The paper discusses a number of existing and proposed applications. 展开更多
关键词 photos silica-glass sonar arrays
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