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Spatial Structure of Central Places in Jilin Central Urban Agglomeration, Jilin Province, China 被引量:1
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作者 WANG Shijun WANG Yongchao WANG Dan 《Chinese Geographical Science》 SCIE CSCD 2014年第3期375-383,共9页
Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China a... Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions. 展开更多
关键词 Jilin Central Urban Agglomeration (JCUA) central place system spatial structure FRACTAL spatial image
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Integrating cross-sensor high spatial resolution satellite images to detect subtle forest vegetation change in the Purple Mountains,a national scenic spot in Nanjing,China 被引量:1
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作者 Fangyan Zhu Wenjuan Shen +2 位作者 Jiaojiao Diao Mingshi Li Guang Zheng 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1743-1758,共16页
Accurate information on the location and magnitude of vegetation change in scenic areas can guide the configuration of tourism facilities and the formulation of vegetation protection measures.High spatial resolution r... Accurate information on the location and magnitude of vegetation change in scenic areas can guide the configuration of tourism facilities and the formulation of vegetation protection measures.High spatial resolution remote sensing images can be used to detect subtle vegetation changes.The major objective of this study was to map and quantify forest vegetation changes in a national scenic location,the Purple Mountains of Nanjing,China,using multi-temporal cross-sensor high spatial resolution satellite images to identify the main drivers of the vegetation changes and provide a reference for sustainable management.We used Quickbird images acquired in 2004,IKONOS images acquired in 2009,and WorldView2 images acquired in 2015.Four pixel-based direct change detection methods including the normalized difference vegetation index difference method,multi-index integrated change analysis(MIICA),principal component analysis,and spectral gradient difference analysis were compared in terms of their change detection performances.Subsequently,the best pixel-based detection method in conjunction with object-oriented image analysis was used to extract subtle forest vegetation changes.An accuracy assessment using the stratified random sampling points was conducted to evaluate the performance of the change detection results.The results showed that the MIICA method was the best pixel-based change detection method.And the object-oriented MIICA with an overall accuracy of 0.907 and a kappa coefficient of 0.846 was superior to the pixel-based MIICA.From 2004 to 2009,areas of vegetation gain mainly occurred around the periphery of the study area,while areas of vegetation loss were observed in the interior and along the boundary of the study area due to construction activities,which contributed to 79%of the total area of vegetation loss.During 2009–2015,the greening initiatives around the construction areas increased the forest vegetation coverage,accounting for 84%of the total area of vegetation gain.In spite of this,vegetation loss occurred in the interior of the Purple Mountains due to infrastructure development that caused conversion from vegetation to impervious areas.We recommend that:(1)a local multi-agency team inspect and assess law enforcement regarding natural resource utilization;and(2)strengthen environmental awareness education. 展开更多
关键词 High spatial resolution satellite images Vegetation change Direct detection method Objectoriented Purple Mountains
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Analysis and Enlightenment on Continuation of Spatial Image of Traditional Streets and Lanes in Historical Urban Area:A Case Study of Spatial Design of Traditional Streets and Lanes in Xin’gan South Road of Ganzhou City 被引量:1
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作者 GUO Song HUANG Meiling LI Zhi 《Journal of Landscape Research》 2020年第6期101-104,107,共5页
Traditional block of Xin’gan South Road in Ganzhou City is taken as the research object.Using urban design techniques,spatial structure,spatial interface,scale,ratio and spatial node of traditional streets and lanes ... Traditional block of Xin’gan South Road in Ganzhou City is taken as the research object.Using urban design techniques,spatial structure,spatial interface,scale,ratio and spatial node of traditional streets and lanes are controlled and processed,and spatial image is analyzed.Moreover,the strategic transformation proposal is put forward.It promotes the renewal of traditional streets and lanes in urban renewal,and realizes the historical continuation of spatial image of traditional streets and lanes,thereby protecting the historical features of the ancient city. 展开更多
关键词 Public space Traditional streets and lanes spatial image Block of Xin’gan South Road
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Monitoring of Karst Rocky Desertification Control Projects Based on Remote Sensing Images with Medium and High Spatial Resolution——A Case Study of Disi River Basin in Puan County 被引量:1
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作者 Haixiang Guo Yulun An 《Meteorological and Environmental Research》 CAS 2013年第7期32-34,38,共4页
[ Objective] The study aimed to improve methods of monitoring Karst Rocky Desertification (KRD) control projects and increase the working efficiency. [Method] Based on remote sensing images with medium and high spat... [ Objective] The study aimed to improve methods of monitoring Karst Rocky Desertification (KRD) control projects and increase the working efficiency. [Method] Based on remote sensing images with medium and high spatial resolution, KRD control projects in Disi River basin in Puan County were monitored, that is, information of the project construction in the study area was extracted using supervised classification and hu- man-computer interactive interpretation, and the monitoring results were testified with the aid of GPS. [Result] It was feasible to monitor KRD con- trol projects in Disi River basin based on remote sensing images with medium and high resolution, and the monitoring accuracy was satisfactory, reaching above 80% or 90%, so the method is worthy of popularizing. [ Conclusion] Remote sensing images with medium and high resolution can be used to monitor other KRD control Droiects. 展开更多
关键词 Karst Rocky Desertification (KRD) Remote sensing images with medium and high spatial resolution MONITORING Puan County China
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Campus Design Strategies Based on Spatial Images: A Case Study of Four New Campuses in Chengdu
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作者 YU Yang QIAN Yuexi +2 位作者 ZHAO Bo ZHU Qibin YAN Jie 《Journal of Landscape Research》 2018年第2期5-10,14,共7页
From 1999, with the rapid expansion of enrollment scale, colleges have experienced fast development and construction of new campuses. However, the urgency of the demand for campus space at that time led to the shortco... From 1999, with the rapid expansion of enrollment scale, colleges have experienced fast development and construction of new campuses. However, the urgency of the demand for campus space at that time led to the shortcomings of paying more attention to speed than connotation during the construction of the new campus. Even now the evaluation of new campuses which have been used for nearly twenty years and whether the space of new campuses has played its due role will affect the display of the heritage and temperament of colleges. This paper uses the typical spatial cognitive concept—spatial image to analyse the elements of spatial images on campuses, summarizes the perceptions of teachers and students towards the space of four new campuses in Chengdu through questionnaire survey and analysis, puts forward the principles of campus space design and the strategies of classification design, and intends to take spatial images as the research cut-in point to provide new ideas and suggestions for the design and improvement of campus space from the perspective of users. 展开更多
关键词 spatial images New campuses Design strategies Campus space
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Three-dimensional quantication of protoporphyrin IX in photodynamic therapy using SFDI/DFT:A pilot experimental validation
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作者 Mai Dan Weijie Song +2 位作者 Meihui Liu Yaru Zhang Feng Gao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第6期30-39,共10页
Photodynamic therapy(PDT)dosimetry,induding light dose,photosensitizer dose and tissue oxygen,has been a research focus in PDT.In this work,we present a three-dimensional(3D)quantification of protoporphyrin X(PpIX)usi... Photodynamic therapy(PDT)dosimetry,induding light dose,photosensitizer dose and tissue oxygen,has been a research focus in PDT.In this work,we present a three-dimensional(3D)quantification of protoporphyrin X(PpIX)using combined spatial frequency domain imaging(SFDI)and diffuse fuorescence tomography(DFT).The SFDI maps both the distributions of tissue absorption and scattering properties at three wavelengths and accordingly provides the optical background for DFT and extracts the tissue oxygenation for assessing the therapeutic outcomes,while DFT dynamically monitors the 3D distribution of PpEX dose from measured fluorescence signals for the procedure optimization.A pilot in vrivo application in tumor nude models showed that the proposed SFDI/DFT is able to dynamically trace changes in the PpX concentration and tissue oaxygen during the treatment,rendering it a potentially powerful tool for PDT to improve clinical eficacy. 展开更多
关键词 Photodynamic therapy spatial frequency domain imaging difuse fuorescence tomography
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Test and Evaluation of Aviation Die Tyre Accuracy Based on Industrial Photogrammetry
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作者 Guiping Huang Wenfang Zhu +2 位作者 Weifeng Wang Xiaoliang Xie Hewei Wang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期393-398,共6页
According to the operational conditions of an aviation module reticule,a measurement mode is proposed,which is based on an industrial photogrammetry system,with matching by a measuring pen.Meanwhile,the factors affect... According to the operational conditions of an aviation module reticule,a measurement mode is proposed,which is based on an industrial photogrammetry system,with matching by a measuring pen.Meanwhile,the factors affecting the accuracy of the measurement have been analyzed and verified by examples.The analysis is described as follows:①Along the optical axis of the camera,the error is larger than the ones in other directions using the“single camera+measuring pen”mode;②By avoiding the error along the optical axis of the camera,the accuracy of the“single camera+measuring pen”mode is better than 0.1 mm when the measuring pen is moving parallel to the optical axis. 展开更多
关键词 module reticule single camera+measuring pen spatial resection of single images REPEATABILITY ACCURACY
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3D image reconstruction with controllable spatial filtering based on correlation of multiple periodic functions in computational integral imaging
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作者 Jae-Young Jang Myungjin Cho Eun-Soo Kim 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第3期22-26,共5页
We propose a novel method of slice image reconstruction with controllable spatial filtering by using the correlation of periodic delta-function arrays (PDFAs) with elemental images in computational integral imaging.... We propose a novel method of slice image reconstruction with controllable spatial filtering by using the correlation of periodic delta-function arrays (PDFAs) with elemental images in computational integral imaging. The multiple PDFAs, whose spatial periods correspond to object's depths with the elemental image array (EIA), can generate a set of spatially filtered EIAs for multiple object depths compared with the conventional method for the depth of a single object. We analyze a controllable spatial filtering effect by the proposed method. To show the feasibility of the proposed method, we carry out preliminary experiments for multiple objects and present the results. 展开更多
关键词 image reconstruction with controllable spatial filtering based on correlation of multiple periodic functions in computational integral imaging EIA
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A Spatial Domain Quantum Watermarking Scheme
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作者 魏战红 陈秀波 +2 位作者 徐淑奖 钮心忻 杨义先 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第7期66-76,共11页
This paper presents a spatial domain quantum watermarking scheme. For a quantum watermarking scheme,a feasible quantum circuit is a key to achieve it. This paper gives a feasible quantum circuit for the presented sche... This paper presents a spatial domain quantum watermarking scheme. For a quantum watermarking scheme,a feasible quantum circuit is a key to achieve it. This paper gives a feasible quantum circuit for the presented scheme. In order to give the quantum circuit, a new quantum multi-control rotation gate, which can be achieved with quantum basic gates, is designed. With this quantum circuit, our scheme can arbitrarily control the embedding position of watermark images on carrier images with the aid of auxiliary qubits. Besides reversely acting the given quantum circuit, the paper gives another watermark extracting algorithm based on quantum measurements. Moreover, this paper also gives a new quantum image scrambling method and its quantum circuit. Differ from other quantum watermarking schemes, all given quantum circuits can be implemented with basic quantum gates. Moreover, the scheme is a spatial domain watermarking scheme, and is not based on any transform algorithm on quantum images. Meanwhile, it can make sure the watermark be secure even though the watermark has been found. With the given quantum circuit, this paper implements simulation experiments for the presented scheme. The experimental result shows that the scheme does well in the visual quality and the embedding capacity. 展开更多
关键词 quantum cryptography quantum images quantum watermark spatial domain quantum watermark
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Minimizing the effects of unmodulated light and uneven intensity profile on the holographic images reconstructed by pixelated spatial light modulators
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作者 Jhen-Si Chen Jia Jia and Daping Chu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第10期42-45,共4页
A simple and effective approach is proposed to minimize the effect of unmodulated light and uneven intensity caused by the pixelated structure of the spatial light modulator in a holographic display. A more uniform im... A simple and effective approach is proposed to minimize the effect of unmodulated light and uneven intensity caused by the pixelated structure of the spatial light modulator in a holographic display. A more uniform image is produced by purposely shifting the holographic images of multiple reconstructed lights with different incident angles from the zero-diffraction-order and overlapping those selected different orders. The simulation and optical experimental results show that the influence of the zero-diffraction-order can be reduced, while keeping the good uniformity of the target images by this new approach. 展开更多
关键词 Minimizing the effects of unmodulated light and uneven intensity profile on the holographic images reconstructed by pixelated spatial light modulators
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Innovative Analysis Ready Data(ARD)product and process requirements,software system design,algorithms and implementation at the midstream as necessary-but-notsufficient precondition of the downstream in a new notion of Space Economy 4.0-Part 2:Software developments 被引量:1
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作者 Andrea Baraldi Luca D.Sapia +3 位作者 Dirk Tiede Martin Sudmanns Hannah Augustin Stefan Lang 《Big Earth Data》 EI CSCD 2023年第3期694-811,共118页
Aiming at the convergence between Earth observation(EO)Big Data and Artificial General Intelligence(AGI),this paper consists of two parts.In the previous Part 1,existing EO optical sensory imagederived Level 2/Analysi... Aiming at the convergence between Earth observation(EO)Big Data and Artificial General Intelligence(AGI),this paper consists of two parts.In the previous Part 1,existing EO optical sensory imagederived Level 2/Analysis Ready Data(ARD)products and processes are critically compared,to overcome their lack of harmonization/standardization/interoperability and suitability in a new notion of Space Economy 4.0.In the present Part 2,original contributions comprise,at the Marr five levels of system understanding:(1)an innovative,but realistic EO optical sensory image-derived semantics-enriched ARD co-product pair requirements specification.First,in the pursuit of third-level semantic/ontological interoperability,a novel ARD symbolic(categorical and semantic)co-product,known as Scene Classification Map(SCM),adopts an augmented Cloud versus Not-Cloud taxonomy,whose Not-Cloud class legend complies with the standard fully-nested Land Cover Classification System’s Dichotomous Phase taxonomy proposed by the United Nations Food and Agriculture Organization.Second,a novel ARD subsymbolic numerical co-product,specifically,a panchromatic or multispectral EO image whose dimensionless digital numbers are radiometrically calibrated into a physical unit of radiometric measure,ranging from top-of-atmosphere reflectance to surface reflectance and surface albedo values,in a five-stage radiometric correction sequence.(2)An original ARD process requirements specification.(3)An innovative ARD processing system design(architecture),where stepwise SCM generation and stepwise SCM-conditional EO optical image radiometric correction are alternated in sequence.(4)An original modular hierarchical hybrid(combined deductive and inductive)computer vision subsystem design,provided with feedback loops,where software solutions at the Marr two shallowest levels of system understanding,specifically,algorithm and implementation,are selected from the scientific literature,to benefit from their technology readiness level as proof of feasibility,required in addition to proven suitability.To be implemented in operational mode at the space segment and/or midstream segment by both public and private EO big data providers,the proposed EO optical sensory image-derived semantics-enriched ARD product-pair and process reference standard is highlighted as linchpin for success of a new notion of Space Economy 4.0. 展开更多
关键词 Analysis Ready Data Artificial General Intelligence Artificial Narrow Intelligence big data cognitive science computer vision Earth observation essential climate variables Global Earth Observation system of(component)systems inductive/deductive/hybrid inference Scene Classification Map Space Economy 4.0 radiometric corrections of optical imagery from atmospheric topographic adjacency and bidirectional reflectance distribution function effects semantic content-based image retrieval 2D spatial topology-preserving/retinotopic image mapping world ontology(synonym for conceptual/mental/perceptual model of the world)
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Innovative Analysis Ready Data(ARD)product and process requirements,software system design,algorithms and implementation at the midstream as necessary-but-notsuffcient precondition of the downstream in a new notion of Space Economy 4.0-Part 1:Problem background in Artificial General Intelligence(AGI) 被引量:1
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作者 Andrea Baraldi Luca D.Sapia +3 位作者 Dirk Tiede Martin Sudmanns Hannah L.Augustin Stefan Lang 《Big Earth Data》 EI CSCD 2023年第3期455-693,共239页
Aiming at the convergence between Earth observation(EO)Big Data and Artificial General Intelligence(AGI),this two-part paper identifies an innovative,but realistic EO optical sensory imagederived semantics-enriched An... Aiming at the convergence between Earth observation(EO)Big Data and Artificial General Intelligence(AGI),this two-part paper identifies an innovative,but realistic EO optical sensory imagederived semantics-enriched Analysis Ready Data(ARD)productpair and process gold standard as linchpin for success of a new notion of Space Economy 4.0.To be implemented in operational mode at the space segment and/or midstream segment by both public and private EO big data providers,it is regarded as necessarybut-not-sufficient“horizontal”(enabling)precondition for:(I)Transforming existing EO big raster-based data cubes at the midstream segment,typically affected by the so-called data-rich information-poor syndrome,into a new generation of semanticsenabled EO big raster-based numerical data and vector-based categorical(symbolic,semi-symbolic or subsymbolic)information cube management systems,eligible for semantic content-based image retrieval and semantics-enabled information/knowledge discovery.(II)Boosting the downstream segment in the development of an ever-increasing ensemble of“vertical”(deep and narrow,user-specific and domain-dependent)value–adding information products and services,suitable for a potentially huge worldwide market of institutional and private end-users of space technology.For the sake of readability,this paper consists of two parts.In the present Part 1,first,background notions in the remote sensing metascience domain are critically revised for harmonization across the multidisciplinary domain of cognitive science.In short,keyword“information”is disambiguated into the two complementary notions of quantitative/unequivocal information-as-thing and qualitative/equivocal/inherently ill-posed information-as-data-interpretation.Moreover,buzzword“artificial intelligence”is disambiguated into the two better-constrained notions of Artificial Narrow Intelligence as part-without-inheritance-of AGI.Second,based on a betterdefined and better-understood vocabulary of multidisciplinary terms,existing EO optical sensory image-derived Level 2/ARD products and processes are investigated at the Marr five levels of understanding of an information processing system.To overcome their drawbacks,an innovative,but realistic EO optical sensory image-derived semantics-enriched ARD product-pair and process gold standard is proposed in the subsequent Part 2. 展开更多
关键词 Artificial Narrow Intelligence big data cognitive science computer vision Earth observation essential climate variables Global Earth Observation system of(component)systems inductive/deductive/hybrid inference Scene Classification Map Space Economy 4.0 radiometric corrections of optical imagery from atmospheric topographic adjacency and bidirectional reflectance distribution function effects semantic content-based image retrieval 2D spatial topology-preserving/retinotopic image mapping world ontology(synonym for conceptual/mental/perceptual model of the world)
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