摘要：
The grey value g (x, y)of pixel on radiometric spectrum is regarded as a function of the geometric coordinates (x, y). Hence, there is a unity of opposite relationships between the geometric and radiometric information, such that, these two types of information cannot be separated. Therefore, this paper proposes a novel geometric and radiometric simultaneous correction model (GRSCM) framework inspired and developed from least squares matching (LSM). Based on the Gauss-Markov model, geometric and radiometric correction coefficients are integrated and solved by an iterative method with variable weights in the proposed model. Moreover, many state-of-the-art models and methods can be integrated into the proposed general GRSCM framework. In the GRSCM of this paper, RAN-dom SAmple Consensus (RANSAC), step wise regression and significance testing are integrated and used. The experimental results demonstrate that the accuracy of the GRSCM is significantly improved compared with that of geometric correction and radiometric correction separately.
作者机构：
[Zhang, HuCai; Li, HuaYong; Zhang, WenXiang; Chang, FengQin] Yunnan Normal Univ, Key Lab Plateau Lake Ecol & Global Change, Yunnan Prov Key Lab Plateau Geog Proc & Environm, Coll Tourism & Geog Sci, Kunming 650500, Yunnan, Peoples R China.;[Li, HuaYong] Anyang Normal Univ, Sch Resource Environm & Tourism, Anyang 455000, Peoples R China.;[Zheng, Qian] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.;[Lei, GuoLiang] Fujian Normal Univ, Key Lab Subtrop Mt Ecol, Minist Sci & Technol & Fujian Prov Funded, Fuzhou 350007, Fujian, Peoples R China.;[Lei, YanBin] Chinese Acad Sci, Inst Tibetan Plateau Res, Lab Tibetan Environm Changes & Land Surface Proc, Beijing 100085, Peoples R China.
通讯机构：
[Zhang, HC; Chang, FQ] Y;Yunnan Normal Univ, Coll Tourism & Geog Sci, Key Lab Plateau Lake Ecol & Global Change, Yunnan Prov Key Lab Plateau Geog Proc & Environm, Kunming 650500, Yunnan, Peoples R China.
关键词：
Lake Zigetang;Tibetan Plateau;Meromictic lakes;Thermocline;Anoxygenic phototrophic bacteria
摘要：
Lake Zigetang is located on the central Tibetan Plateau (TP) and represents a rare but typical meromictic lake in China. The lake's stable meromixis sustains microflora communities, and changes in these communities are relatively independent of climate. Therefore, these communities can be used as paleoclimate proxies. In this paper, the stratification properties and their relationships with the microflora of Lake Zigetang were analyzed. We found that water depth and climate conditions were two important factors for maintaining meromixis in Lake Zigetang. Generally, stratification was enhanced during warm periods, while temperature differences between the mixolimnion and monimolimnion were decreased during cold periods. The presence of anoxygenic phototrophic bacteria (APB) was demonstrated by the discovery of bacteriopheophytin-a (Bph-a) in the sediments. This bacterial community is mainly concentrated at the bottom of the chemocline and the top of the monimolimnion, where it forms a thin APB layer. Moreover, total APB productivity is mainly affected by the light intensity penetrating to the APB layer, which exponentially increases as the thermocline becomes shallow. Therefore, high Bph-a values in the lake corresponded to a shallow thermocline and warm periods, low Bph-a values corresponded to cold periods, and zero changes indicated that the water was completely mixed and reflected an extreme cold climate or low lake level period. Thus, Bph-a can be used as a climate proxy to reconstruct the history of lake stratification and climate changes.
期刊：
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives,2017年42(2W7):857-861 ISSN：1682-1750
通讯作者：
Peng, Feifei(feifpeng@163.com)
作者机构：
[Peng, Feifei; Tan, Wenxia] Key Laboratory for Geographical Process Analysis and Simulation of Hubei Province, Central China Normal University, Wuhan, 430079, China;[Cai, Xiaoyu] Communication Technology Engineering Co., Ltd., China Mobile Hubei Branch, Wuhan, 430010, China;[Peng, Feifei; Tan, Wenxia] College of Urban and Environmental Sciences, Central China Normal University, Wuhan, 430079, China
期刊：
International Journal of Remote Sensing,2017年38(21):6007-6029 ISSN：0143-1161
通讯作者：
Li, Chang
作者机构：
[Luo, Jing; Chen, Guangping; Li, Shice; Li, Chang] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat, Wuhan, Hubei, Peoples R China.;[Luo, Jing; Chen, Guangping; Li, Shice; Li, Chang] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan, Hubei, Peoples R China.;[Ye, Jia] Georgia Inst Technol, Sch Design, Atlanta, GA 30332 USA.;[Li, Chang] Cent China Normal Univ, Key Lab Geog Proc Anal Simulat, Wuhan, Hubei, Peoples R China.
通讯机构：
[Li, Chang] C;Cent China Normal Univ, Key Lab Geog Proc Anal Simulat, Wuhan, Hubei, Peoples R China.
摘要：
In this article, the Defence Meteorological Satellite Program Operational Linescan System DMSP-OLS night-time light remotely sensed data on a small scale is proposed to evaluate port economic comprehensive scores PECS for the ports of the major cities, including Shanghai, Nanjing, Wuhan, and Chongqing, in the Yangtze River Valley, China. First, the concept and calculation method of port night-time light intensity PNLI are proposed. Second, an estimation method of PECS is proposed using factor analysis. Third, two regression models i.e. first-and second-order polynomials between PNLI and PECS are built and tested. The goodness-of-fit of the two models are compared, both with and without outliers. Finally, experimental results show that the proposed methods for evaluating PECS in the Yangtze River Valley, China are feasible. Wuhan has the strongest correlation R2 = 0.925 and passes the F-test, Ft = 55.429 >4.26 = Ft 0.05 2, 9; Shanghai has the weakest correlation R2: 0.688 but still passes as well, Ft = 9.944 >4.26 = Ft0.05 2, 9. Factors confounding the correlation for Shanghai are discussed. Overall, this study not only proposes a new set of methods to evaluate the performance of port economies but also provides a feasible way to use DMSP-OLS data to study the geographic problems of small scales.
作者机构：
[Peng, Feifei; Liu, Pengcheng] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Peng, Feifei; Liu, Pengcheng] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.;[Gong, Jianya] Wuhan Univ, Sch Remote Sensing & Informat Engn, Wuhan 430079, Peoples R China.;[Gong, Jianya; Wu, Huayi] Wuhan Univ, State Key Lab Informat Engn Surveying Mapping & R, Wuhan 430079, Peoples R China.;[Wang, Le] SUNY Buffalo, Dept Geog, Buffalo, NY 14261 USA.
通讯机构：
[Peng, Feifei] C;Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.
关键词：
built-up area;stereo image;disparity;height feature;Stereo Pair Disparity Index (SPDI)
摘要：
Within-class spectral variation and between-class spectral confusion in remotely sensed imagery degrades the performance of built-up area detection when using planar texture, shape, and spectral features. Terrain slopes and building heights extracted from auxiliary data, such as Digital Surface Models (DSMs) however, can improve the results. Stereo imagery incorporates height information unlike single remotely sensed images. In this study, a new Stereo Pair Disparity Index (SPDI) for indicating built-up areas is calculated from stereo-extracted disparity information. Further, a new method of detecting built-up areas from stereo pairs is proposed based on the SPDI, using disparity information to establish the relationship between two images of a stereo pair. As shown in the experimental results for two stereo pairs covering different scenes with diverse urban settings, the SPDI effectively differentiates between built-up and non-built-up areas. Our proposed method achieves higher accuracy built-up area results from stereo images than the traditional method for single images, and two other widely-applied DSM-based methods for stereo images. Our approach is suitable for spaceborne and airborne stereo pairs and triplets. Our research introduces a new effective height feature (SPDI) for detecting built-up areas from stereo imagery with no need for DSMs.
通讯机构：
[Yu, GM; Tu, ZF] H;[Yu, GM; Tu, ZF] C;Hubei Prov Key Lab Geog Proc Anal & Simulat, Wuhan 430079, Hubei Province, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.
关键词：
Water accessibility;Natural river network;SHRD model;Watershed scale;Water resources management
摘要：
Traditional assessments of water resources use water availability as an evaluating metric. Water availability is a statistical average and cannot reflect the spatial differences of water resources in a region or basin. This assessment usually engenders a paradox, that is, water resources are abundant in a region but it is difficult to obtain water for the people on some spatial points in this region. In this study we define a new term, water accessibility, to eliminate this paradox and develop a model of water accessibility (the SHRD model) to meet the need of spatial details in water resources assessment at the grid scale. In the case study the water accessibility of the Hanjiang River Basin is mapped and assessed by the SHRD model. The comprehensive index of water accessibility is 0 to 4.5 and tends to increase from northwest to southeast in the study area. The results of the SHRD model can show the spatial pattern of water accessibility in a region, and can server a more finely-tuned water resources management approach. This model and method push the macroscopic (regional) water resources assessment forward from the microcosmic (raster cell) analysis.
作者机构：
[李桂娥; 朱昱佳; 李畅] Key Laboratory for Geographical Process Analysis and Simulation, College of City and Environmental Science, Central China Normal University, Wuhan, Hubei Province, 430079, China
关键词：
交通网络;长度-半径维数模型;不确定性;质量控制;误差传播
摘要：
长度-半径维数模型作为描述城市交通网络复杂不确定性现象的一种分形分维方法,其自身存在的不确定性往往被忽视,且相关研究更是鲜见报道。故针对该模型在分形维数测算全过程中存在的不确定性问题,本文率先开展了系统剖析、定量估计和质量控制研究。首先对数据源、矢量化处理、测算中心、尺度选择、以及分维数模型估计等一系列环节进行了不确定性估计与分析,其中首次给出了分形维数在一定置信水平下的不确定性度量区间,并依据误差传播理论对误差的传递和累积进行了描述;然后着重提出了基于LMedS(Least Median of Squares)的质量控制方法。最后通过对拉萨市的算例实验表明:道路的矢量化过程、测算中心和测算尺度的选择都会导致分维的不确定性;并在对数据质量进行控制的基础上,通过置信区间对长度-半径维数模型的不确定性进行了在一定概率水平下的首次度量;同时结合区域现状对研究结果给出了合乎实际的解释。本文在描述表征不确定性问题的分形几何和分形维数的基础上,系统地揭示了其自身不确定性的本质,不仅进一步丰富了分形分维理论,为控制其质量奠定理论基础,而且可为城市交通网络分形维数的地学应用提供可靠的科学依据。
通讯机构：
[Li, Chang] K;[Li, Chang] C;Key Lab Geog Proc Anal & Simulat, Wuhan, Hubei, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
摘要：
There are two major problems in Rational Function Model (RFM) solution: (a) Data source error, including gross error, random error, and systematic error; and (b) Model error, including over-parameterization and over-correction issues caused by unnecessary RFM parameters and exaggeration of random error in constant term of error-in-variables (EIV) model, respectively. In order to solve two major problems simultaneously, we propose a new approach named stepwise-thenorthogonal regression (STOR) with quality control. First, RFM parameters are selected by stepwise regression with gross error detection. Second, the revised orthogonal distance regression is utilized to adjust random error and address the overcorrection problem. Third, systematic error is compensated by Fourier series. The performance of conventional strategies and the proposed STOR are evaluated by control and check grids generated from SPOT5 high-resolution imagery. Compared with the least squares regression, partial least squares regression, ridge regression, and stepwise regression, the proposed STOR shows a significant improvement in accuracy.
期刊：
International Journal of Remote Sensing,2017年38(11):3430-3444 ISSN：0143-1161
通讯作者：
Li, Chang
作者机构：
[Zheng, Yanping; Wu, Yijin; Li, Chang] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat, Hubei, Peoples R China.;[Zheng, Yanping; Wu, Yijin; Li, Chang] Cent China Normal Univ, Coll Urban & Environm Sci, Hubei, Peoples R China.
通讯机构：
[Li, Chang] C;Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat, Hubei, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Hubei, Peoples R China.
期刊：
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives,2017年42(2W7):373-378 ISSN：1682-1750
通讯作者：
Li, Chang(lcshaka@126.com)
作者机构：
[Li, Chang] Key Laboratory for Geographical Process Analysis and Simulation, Hubei Province, Central China Normal University, Wuhan, China;[Kang, Zhizhong] School of Land Science and Technology, China University of Geosciences, Xueyuan Road 29, Haidian District, Beijing, 100083, China;[Wang, Tianli; Li, Guie; Deng, Yong; Li, Chang] College of Urban and Environmental Science, Central China Normal University, Wuhan, China
摘要：
With the rapid development of LBS (Location-based Service), the demand for commercialization of indoor location has been increasing, but its technology is not perfect. Currently, the accuracy of indoor location, the complexity of the algorithm, and the cost of positioning are hard to be simultaneously considered and it is still restricting the determination and application of mainstream positioning technology. Therefore, this paper proposes a method of knowledge-based optimization of indoor location based on low energy Bluetooth. The main steps include: 1) The establishment and application of a priori and posterior knowledge base. 2) Primary selection of signal source. 3) Elimination of positioning gross error. 4) Accumulation of positioning knowledge. The experimental results show that the proposed algorithm can eliminate the signal source of outliers and improve the accuracy of single point positioning in the simulation data. The proposed scheme is a dynamic knowledge accumulation rather than a single positioning process. The scheme adopts cheap equipment and provides a new idea for the theory and method of indoor positioning. Moreover, the performance of the high accuracy positioning results in the simulation data shows that the scheme has a certain application value in the commercial promotion.<br/>
作者机构：
[Li, Jianyong; Dodson, John; Li, JY; Dodson, J; Yan, Hong; Lu, Fengyan] Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Inst Earth Environm, Xian 710075, Peoples R China.;[Dodson, John] Univ New South Wales, Sch Biol Earth & Environm Sci, Sydney, NSW 2033, Australia.;[Zhang, David D.; Lee, Harry F.] Univ Hong Kong, Dept Geog, Pokfulam Rd, Hong Kong, Hong Kong, Peoples R China.;[Zhang, David D.; Lee, Harry F.] Univ Hong Kong, Int Ctr China Dev Study, Pokfulam Rd, Hong Kong, Hong Kong, Peoples R China.;[Zhang, Xiaojian] Nanjing Univ, Sch Geog & Oceanog Sci, Nanjing 210093, Jiangsu, Peoples R China.
摘要：
Our understanding on the spatial-temporal patterns of climatic variability over the last few millennia in the East Asian monsoon-dominated northern China (NC), and its role at a macro-scale in affecting the prosperity and depression of Chinese dynasties is limited. Quantitative high-resolution, regionally-synthesized palaeoclimatic reconstructions as well as simulations, and numerical analyses of their relationships with various fine-scale, numerical agro-ecological, social-economic, and geo-political historical records during the period of China's history, are presented here for NC. We utilize pollen data together with climate modeling to reconstruct and simulate decadal- to centennial-scale variations in precipitation or temperature for NC during the last 2200 years (-200-2000 AD). We find an overall cyclic-pattern (wet/warm or dry/cold) in the precipitation and temperature anomalies on centennial- to millennial-scale that can be likely considered as a representative for the entire NC by comparison with other related climatic records. We suggest that solar activity may play a key role in driving the climatic fluctuations in NC during the last 22 centuries, with its quasi similar to 100, 50, 23, or 22-year periodicity clearly identified in our climatic reconstructions. We employ variation partitioning and redundancy analysis to quantify the independent effects of climatic factors on accounting for the total variation of 17 fine-grained numerical Chinese historical records. We quantitatively illustrate that precipitation (67.4%) may have been more important than temperature (32.5%) in causing the overall agro-ecological and macro-geopolitical shifts in imperial China with NC as the central ruling region and an agricultural heartland over the last 2200 years. (C) 2017 Elsevier Ltd. All rights reserved.
作者机构：
[彭飞飞] College of Urban and Environment Science, Central China Normal University, Wuhan;430079, China;Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan;[彭飞飞] 430079, China<&wdkj&>Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan;[彭飞飞] 430079, China
通讯机构：
[Peng, F.] C;College of Urban and Environment Science, Central China Normal University, Wuhan, China
