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3D Model Construction and Ecological Environment Investigation on a Regional Scale Using UAV Remote Sensing
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作者 Chao Chen Yankun Chen +7 位作者 Haohai Jin Li Chen Zhisong Liu Haozhe Sun Junchi Hong Haonan Wang Shiyu Fang Xin Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1655-1672,共18页
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev... The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. 展开更多
关键词 Unmanned air vehicle multi-spectral camera oblique photography 3D model construction ecological environment investigation regional scale
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Factors affecting land dissection density in geomorphological regions of China
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作者 SUN Xiaolin ZHAO Yinjun +4 位作者 PENG Peihao CHENG Weiming WEI Yongping YANG Ronghao LI Jiaxu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1372-1387,共16页
Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing t... Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters,soil erosion,and other related domains.Land dissection phenomena in China affects large areas with different morphological,pedological,and climatic characteristics.Prior studies have focused on the potential factors influencing the LDD at a watershed scale.However,these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national scale.LDD’s spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be ascertained.This study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China’s six first-order geomorphological regions(GR1~GR6).The results yield the following findings:(1)LDD in China ranges from 0~4.55 km/km^(2),which is larger in central and eastern regions than in other regions of China;(2)dominant factors and their dominant risk subcategories vary with each geomorphological region’s primary internal and external forces;(3)the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors;relief degree of land surface(RDLS)is dominant in GR1,GR2,and GR5;the slope is dominant in GR6,soil type is dominant in GR3 and GR4,and lithology plays a critical role in the dominant interactions of GR3,GR4,and GR6;(4)the interactions between factors on LDD’s spatial pattern have a more significant effect than individual factors. 展开更多
关键词 Land dissection density Influencing factors regional scale Spatial pattern Geographical detector model Geomorphon-based method China
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Assessment of the effects of the shelterbelt on the soil temperature at regional scale based on MODIS data 被引量:3
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作者 DENG Rong-xin LI Ying +2 位作者 ZHANG Shu-wen WANG Wen-juan SHI Xiao-liang 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期65-70,共6页
At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more atten... At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more attention was paid to the regional climate effect of shelterbelt. In present study, we analyzed the temperature effect of the shelterbelt at regional scale by using the land surface temperature (LST) data from the moderate resolution imaging spectroradiometer (MODIS) at Yushu, Nong'an, Dehui, and Fuyu in Jilin Province of China from March to October in 2008. Results show that the shelterbelt can increase the soil temperature of the protected farmland as compared with no shelterbelt zone, with the increment of 0.57oC per day in fine shelterbelt and 0.38oC per day in the normal shelterbelt. Moreover, the correlation analysis of the air temperature, precipitation and the soil type and the shelterbelt effect shows that the air temperature and precipitation are negatively correlated with the shelterbelt effects, that is, the more the temperature and precipitation are, the less the effect produced. While the impact of the soil types on the shelterbelt's effect is not very obvious as a whole. This paper draws significance in terms of analyzing the effects of the shelterbelt on the soil temperature at regional scale utilizing the remotely sensed data and GIS technique. 展开更多
关键词 regional scale remote sensing SHELTERBELT temperature effect
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Evaluation of Land-Use Efficiency Based on Regional Scale——A Case Study in Zhanjiang,Guangdong Province 被引量:8
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作者 CHEN Shi-yin LIU Yao-lin CHEN Cui-fang 《Journal of China University of Mining and Technology》 EI 2007年第2期215-219,共5页
Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,econom... Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,economy,ecology and environment. The weight of each indicator was defined by an analytical hierarchy process (AHP) and the entropy method (EM). Then,a case study in Zhanjiang was carried out to analyze the regional land use efficiency from 1996 to 2004 and its development by using the method of multifactor composite evaluation and an analytical model of the de-gree of coordination. The results indicate that land use efficiency with respect to society and the economy improved,whereas the ecological and environmental efficiencies were found to decrease. The degree of coordination in Zhanjiang is still at the status of basic coordination. Finally,measures for enhancing the ecological and environmental establish-ment are suggested in order to improve the regulations of land use structure and patterns,establish ecological forests for the public good and green corridors and prevent the soil erosion. 展开更多
关键词 regional scale land-use efficiency degree of coordination EVALUATION
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Regional-scale Surface Air Temperature and East Asian Summer Monsoon Changes during the Last Millennium Simulated by the FGOALS-gl Climate System Model 被引量:12
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作者 MAN Wenmin ZHOU Tianjun 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第4期765-778,共14页
The spatial patterns and regional-scale surface air temperature (SAT) changes during the last millennium,as well as the variability of the East Asian summer monsoon (EASM) were simulated with a low-resolution vers... The spatial patterns and regional-scale surface air temperature (SAT) changes during the last millennium,as well as the variability of the East Asian summer monsoon (EASM) were simulated with a low-resolution version of Flexible Global Ocean-Atmosphere-Land-Sea-ice (FGOALS-gl) model.The model was driven by both natural and anthropogenic forcing agents.Major features of the simulated past millennial Northern Hemisphere (NH) mean SAT variations,including the Medieval Climate Anomaly (MCA),the Little Ice Age (LIA) and the 20th Century Warming (20CW),were generally consistent with the reconstructions.The simulated MCA showed a global cooling pattern with reference to the 1961-90 mean conditions,indicating the 20CW to be unprecedented over the last millennium in the simulation.The LIA was characterized by pronounced coldness over the continental extratropical NH in both the reconstruction and the simulation.The simulated global mean SAT difference between the MCA and LIA was 0.14°C,with enhanced warming over high-latitude NH continental regions.Consistencies between the simulation and the reconstruction on regional scales were lower than those on hemispheric scales.The major features agreed well between the simulated and reconstructed SAT variations over the Chinese domain,despite some inconsistency in details among different reconstructions.The EASM circulation during the MCA was stronger than that during the LIA The corresponding rainfall anomalies exhibited excessive rainfall in the north but deficient rainfall in the south.Both the zonal and meridional thermal contrast were enhanced during the MCA.This temperature anomaly pattern favored a stronger monsoon circulation. 展开更多
关键词 last millennium surface air temperature spatial patterns regional-scale variation East Asian summer monsoon
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AN INSIGHT ON DRIVERS OF LAND USE CHANGE AT REGIONAL SCALE 被引量:2
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作者 SHAO Jing-an WEI Chao-fu XIE De-ti 《Chinese Geographical Science》 SCIE CSCD 2006年第2期176-182,共7页
The studies of driving forces of regional land use change (LUC) are to reveal the real motivation behind the LUC and its interacting mechanism, so as to simulate and predict the process of LUC. Presently, studies root... The studies of driving forces of regional land use change (LUC) are to reveal the real motivation behind the LUC and its interacting mechanism, so as to simulate and predict the process of LUC. Presently, studies rooting from different natural and socio-economic backgrounds and from different scales have deepened the people’s understanding and cognition to driving forces of regional LUC. Biophysical driving forces are relatively stable, and have the cumulating effects. Human driving forces are relatively active, and are main driving forces of short-term regional LUC. Existing regional LUC models can answer the three main problems: which contribution (why), which location (where) and what rate (when). But, regional land use system is defined as the self-organized system, usually affected by the cri- tical value area and sudden change, and controlled by different stages. To reduce the impact of critical threshold and break on land use system, the studies of LUC driving forces will aim at following priority areas: data linkage between remote sensing and no-remote sensing data; underlying driving force identification; driving factor quantification; driving factor scale dependence; and driving process integration simulation. 展开更多
关键词 land use change driving forces driving mechanism process simulation regional scale
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A GIS-based Modeling Approach for Fast Assessment of Soil Erosion by Water at Regional Scale, Loess Plateau of China 被引量:2
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作者 HU Llangjun YANG Haijun +1 位作者 YANG Qinke LI Rui 《Chinese Geographical Science》 SCIE CSCD 2010年第5期423-433,共11页
The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of bo... The objective of this study is to develop a unique modeling approach for fast assessment of massive soil erosion by water at a regional scale in the Loess Plateau, China. This approach relies on an understanding of both regional patterns of soil loss and its impact factors in the plateau area. Based on the regional characteristics of precipitation, vegetation and land form, and with the use of Landsat TM and ground investigation data, the entire Loess Plateau was first divided into 3 380 Fundamental Assessment Units (FAUs) to adapt to this regional modeling and fast assessment. A set of easily available parameters reflecting relevant water erosion factors at a regional scale was then developed, in which dynamic and static factors were discriminated. Arclnfo GIS was used to integrate all essential data into a central database. A resulting mathematical model was established to link the sediment yields and the selected variables on the basis of FAUs through overlay in GIS and multiple regression analyses. The sensitivity analyses and validation results show that this approach works effectively in assessing large area soil erosion, and also helps to understand the regional associations of erosion and its impact factors, and thus might significantly contribute to planning and policymaking for a large area erosion control in the Loess Plateau. 展开更多
关键词 soil erosion by water G/S-based modeling soil erosion assessment regional scale Loess Plateau
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On the criteria to create a susceptibility map to debris flow at a regional scale using Flow-R 被引量:2
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作者 PASTORELLO Roberta MICHELINI Tamara D'AGOSTINO Vincenzo 《Journal of Mountain Science》 SCIE CSCD 2017年第4期621-635,共15页
Studies on susceptibility to debris flows at regional scale (ioo-looo km2) are important for the protection and management of mountain areas. To reach this objective, routing models, mainly based on land topography,... Studies on susceptibility to debris flows at regional scale (ioo-looo km2) are important for the protection and management of mountain areas. To reach this objective, routing models, mainly based on land topography, can be used to predict susceptible areas rapidly while necessitating few input data. In this research, Flow-R model is implemented to create the susceptibility map for the debris flow of the Vizze Valley (BZ, North-Eastern Italy; 134 km^2). The analysis considers the model application at local scale for three sub-catchments and then it explores the model upsealing at the regional scale by verifying two methods to generate the source areas of debris-flow initiation. Using data of an extreme event occurred in the Vizze Valley (4 August 2012) and historical information, the modeling verification highlights that the propagation parameters are relatively simple to set in order to obtain correct runout distances. A double DTM filtering - using a threshold for the upslope contributing area (0.1 km^2) and a threshold for the terrain-slope angle (15°) provides a satisfactory prediction of source areas and susceptibility map within the geological conditions of the Vizze Valley. 展开更多
关键词 Debris flow Susceptibility map Flow-R Triggering areas regional scale Alpine valley
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Spatial Agglomeration of Exhibition Enterprises on a Regional Scale in China 被引量:1
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作者 FANG Zhongquan ZHANG Ying +1 位作者 WANG Zhangjun ZHANG Lifeng 《Chinese Geographical Science》 SCIE CSCD 2017年第3期497-506,共10页
During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition e... During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition enterprises highlighted on the regional scale. Although the development of theoretical research on the western exhibition industry has taken place over time, the spatial perspective has not been at the centre of attention so far. This paper aims to fill this gap and report on the agglomeration characteristics of exhibition enterprises and their influential factors. Based on data about exhibition enterprises in the Pearl River Delta(PRD) during 1991–2013, using the Ripley K function analysis and kernel density estimation, this research identifies that: 1) the exhibition enterprise on the regional scale is significantly characterized by spatial agglomeration, and the agglomeration density and scale are continuously increasing; 2) the spatial pattern of agglomeration has developed from a single-center to multi-center form. Meanwhile, this paper profiles the factors influencing the spatial agglomeration of exhibition enterprises by selecting the panel data of nine cities in the PRD in 1999, 2002, 2006 and 2013. The results show that market capacity, urban informatization level and exhibition venues significantly influence the location choice of exhibition enterprises. Among them, the market capacity is a variable that exerts a far greater impact than other factors do. 展开更多
关键词 exhibition enterprises spatial agglomeration Ripley K function analysis regional scale Pearl River Delta
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New approach to calculating tree height at the regional scale
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作者 Congrong Li Jinling Song Jindi Wang 《Forest Ecosystems》 SCIE CSCD 2021年第2期311-329,共19页
Background:Determining the spatial distribution of tree heights at the regional area scale is significant when performing forest above-ground biomass estimates in forest resource management research.The geometric-opti... Background:Determining the spatial distribution of tree heights at the regional area scale is significant when performing forest above-ground biomass estimates in forest resource management research.The geometric-optical mutual shadowing(GOMS)model can be used to invert the forest canopy structural parameters at the regional scale.However,this method can obtain only the ratios among the horizontal canopy diameter(CD),tree height,clear height,and vertical CD.In this paper,we used a semi-variance model to calculate the CD using high spatial resolution images and expanded this method to the regional scale.We then combined the CD results with the forest canopy structural parameter inversion results from the GOMS model to calculate tree heights at the regional scale.Results:The semi-variance model can be used to calculate the CD at the regional scale that closely matches(mainly with in a range from-1 to 1 m)the CD derived from the canopy height model(CHM)data.The difference between tree heights calculated by the GOMS model and the tree heights derived from the CHM data was small,with a root mean square error(RMSE)of 1.96 for a 500-m area with high fractional vegetation cover(FVC)(i.e.,forest area coverage index values greater than 0.8).Both the inaccuracy of the tree height derived from the CHM data and the unmatched spatial resolution of different datasets will influence the accuracy of the inverted tree height.And the error caused by the unmatched spatial resolution is small in dense forest.Conclusions:The semi-variance model can be used to calculate the CD at the regional scale,together with the canopy structure parameters inverted by the GOMS model,the mean tree height at the regional scale can be obtained.Our study provides a new approach for calculating tree height and provides further directions for the application of the GOMS model. 展开更多
关键词 Geometric-optical mutual shadowing(GOMS)model Semi-variance model Canopy diameter Tree height regional scale
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The Functional Role of the Hollow Region of the Butterfly Pyrameis atalanta (L.) Scale 被引量:1
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作者 Igor Kovalev 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第3期224-230,共7页
Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta (L.) scale are experimentally investigated. Attention was initially directed to this problem by observation of the com... Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta (L.) scale are experimentally investigated. Attention was initially directed to this problem by observation of the complex microstrucmre of the butterfly scale as well as other studies indicating higher lift on butterfly wings covered with scale. The aerodynamic forces were measured for two oscillating scale models. Results indicated that the air cavity of an oscillating model of the Pyrameis atalanta (L.) scale increased the lift by a factor of 1.15 and reduced the damping coefficients by a factor of 1.38. The modification of the aerodynamic effects on the model of butterfly scale was due to an increase of the virtual air mass, which influenced the body. The hollow region of the scale increased the virtual air mass by a factor of 1.2. The virtual mass of the butterfly scale with the hollow region was represented as the sum of air mass of two imaginary geometrical figures: a circular cylinder around the scale and a right-angled parallelepiped within the hollow region. The interaction mechanism of the butterfly Pyrameis atalanta (L.) scale with a flow was described. This novel interaction mechanism explained most geometrical features of the airpermeable butterfly scale (inverted V-profile of the ridges, nozzle of the tip edge, hollow region, and openings of the upper lamina) and their arrangement. 展开更多
关键词 BIONIC butterfly scale hollow region damped coefficient flapping motion virtual mass
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Study on Multi-Scale Blending Initial Condition Perturbations for a Regional Ensemble Prediction System 被引量:28
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作者 ZHANG Hanbin CHEN Jing +2 位作者 ZHI Xiefei WANG Yi WANG Yanan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第8期1143-1155,共13页
An initial conditions (ICs) perturbation method was developed with the aim to improve an operational regional ensemble prediction system (REPS). Three issues were identified and investigated: (1) the impacts of... An initial conditions (ICs) perturbation method was developed with the aim to improve an operational regional ensemble prediction system (REPS). Three issues were identified and investigated: (1) the impacts of perturbation scale on the ensemble spread and forecast skill of the REPS; (2) the scale characteristic of the IC perturbations of the REPS; and (3) whether the REPS's skill could be improved by adding large-scale information to the IC perturbations. Numerical experiments were conducted to reveal the impact of perturbation scale on the ensemble spread and forecast skill. The scales of IC perturbations from the REPS and an operational global ensemble prediction system (GEPS) were analyzed. A "multi-scale blending" (MSB) IC perturbation scheme was developed, and the main findings can be summarized as follows: The growth rates of the ensemble spread of the REPS are sensitive to the scale of the IC perturbations; the ensemble forecast skills can benefit from large-scale perturbations; the global ensemble IC perturbations exhibit more power at larger scales, while the regional ensemble IC perturbations contain more power at smaller scales; the MSB method can generate IC perturbations by combining the small-scale component from the REPS and the large-scale component from the GEPS; the energy norm growth of the MSB-generated perturbations can be appropriate at all forecast lead times; and the MSB-based REPS shows higher skill than the original system, as determined by ensemble forecast verification. 展开更多
关键词 regional ensemble prediction system spectral analysis multi-scale blending initial condition perturbations
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Local and regional richness and rarity of leaf-litter ants:An overview from spacial scale in neotropical region
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作者 Manoel Fernando Demétrio Rogério Silvestre 《Open Journal of Animal Sciences》 2013年第2期10-15,共6页
An unusual approach about richness and rarity of leaf-litter ant species is presented here from a dry forest reminiscent in Pantanal province (Chacoan subregion) suggesting the boundaries that defining local and regio... An unusual approach about richness and rarity of leaf-litter ant species is presented here from a dry forest reminiscent in Pantanal province (Chacoan subregion) suggesting the boundaries that defining local and regional scales for this particular ant community. We analysed the frequency of distribution of 170 ant species collected on 262 Winkler’s samples along Serra da Bodoquena National Park, Mato Grosso do Sul state, Brazil and described some ecological mechanisms that made the species richness estimates be highly influenced by species with low frequencies of records in an extent regional of a pristine dry forest. Bayesian inference was conducted to provide if the probability of latitudinal gradient was correlated with the species richness to define alpha diversity. 展开更多
关键词 Alpha Diversity FORMICIDAE Rarity Patterns regional scale
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Multi-scale regionalization based mining of spatio-temporal teleconnection patterns between anomalous sea and land climate events
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作者 XU Feng SHI Yan +3 位作者 DENG Min GONG Jian-ya LIU Qi-liang JIN Rui 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2438-2448,共11页
Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-de... Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate. 展开更多
关键词 CLIMATE sequences ANOMALOUS climatic EVENTS SPATIO-TEMPORAL teleconnection patterns MULTI-scale regionALIZATION
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Down-scaled regional ocean modeling system (ROMS) for high-resolution coastal hydrodynamics in Korea 被引量:4
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作者 LIM Hak-Soo KIM Chang S +2 位作者 PARK Kwang-Soon SHIM Jae Seol CHUN Insik 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第9期50-61,共12页
A down-scaled operational oceanographic system is developed for the coastal waters of Korea using a re- gional ocean modeling system (ROMS). The operational oceanographic modeling system consists of at- mospheric an... A down-scaled operational oceanographic system is developed for the coastal waters of Korea using a re- gional ocean modeling system (ROMS). The operational oceanographic modeling system consists of at- mospheric and hydrodynamic models. The hydrodynamic model, ROMS, is coupled with wave, sediment transport, and water quality modules. The system forecasts the predicted results twice a day on a 72 h basis, including sea surface elevation, currents, temperature, salinity, storm surge height, and wave information for the coastal waters of Korea. The predicted results are exported to the web-GIS-based coastal informa- tion system for real-time dissemination to the public and validation with real-time monitoring data using visualization technologies. The ROMS is two-way coupled with a simulating waves nearshore model, SWAN, for the hydrodynamics and waves, nested with the meteorological model, WRE for the atmospheric surface forcing, and externally nested with the eutrophication model, CE-QUAL-ICM, for the water quality. The op- erational model, ROMS, was calibrated with the tidal surface observed with a tide-gage and verified with current data observed by bottom-mounted ADCP or AWAC near the coastal waters of Korea. To validate the predicted results, we used real-time monitoring data derived from remote buoy system, HF-radar, and geostationary ocean color imager (GOCI). This down-scaled operational coastal forecasting system will be used as a part of the Korea operational oceanographic system (KOOS) with other operational oceanographic systems. 展开更多
关键词 down-scaled operational oceanographic system regional ocean modeling system wave coupledmodel real-time monitoring system
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Sap-flow measurement and scale transferring from sample trees to entire forest stand of Populus euphratica in desert riparian forest in extreme arid region 被引量:2
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作者 JianHua Si 1, Qi Feng 1, HaiYang Xi 1, ZongQiang Chang 1, YongHong Su 1, Kai Zhang 1,2 1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China. 2. Institute of Arid Meteorology, China Meteorological Administration, Lanzhou, Gansu 730020, China. 《Research in Cold and Arid Regions》 2009年第3期258-266,共9页
Understanding how the transpiration of this vegetation type responds to environmental stress is important for determining the wa-ter-balance dynamics of the riparian ecosystem threatened by groundwater depletion. Tran... Understanding how the transpiration of this vegetation type responds to environmental stress is important for determining the wa-ter-balance dynamics of the riparian ecosystem threatened by groundwater depletion. Transpiration and sap flow were measured using the heat-pulse technique. The results were then projected up to the stand level to investigate the stand’s water-use in relation to climate forcing in the desert riparian forest in an extreme arid region. This study took place from April through October 2003 and from May through October 2004. The experimental site was selected in the Populus euphratica Forest Reserve (101o10' E, 41o59' N) in Ejina county, in the lower Heihe River basin, China. The sapwood area was used as a scalar to extrapolate the stand-water consumption from the whole trees’ water consumption measured by the heat-pulse velocity recorder (HPVR). Scale transferring from a series of individual trees to a stand was done according to the existing natural variations between trees under given environmental conditions. The application of the biometric parameters available from individual tree and stand levels was proved suitable for this purpose. A significant correlation between the sapwood area and tree diameter at breast height (DBH) was found. The prediction model is well fitted by the power model. On the basis of the prediction model, the sapwood area can be cal-culated by DBH. The sap-flow density can then be used to extrapolate the stand-water use by means of a series of mathematical models. 展开更多
关键词 sap flow heat-pulse technique sapwood area scale transferring extreme arid region Populus euphratica
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一种大尺度区域GNSS坐标时间序列自适应时空滤波方法 被引量:1
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作者 刘斌 肖紫恩 +1 位作者 骆亚波 蒋一帆 《大地测量与地球动力学》 CSCD 北大核心 2024年第8期793-796,846,共5页
提出一种GNSS坐标时间序列自适应时空滤波方法,在规定阈值下将滤波区域自适应分为若干个子区域,进行共模误差的提取和去除。对陆态网184个GNSS站点垂向坐标序列进行时空滤波,3组随机实验中,自适应PCA时空滤波后的站点序列平均RMS值减少... 提出一种GNSS坐标时间序列自适应时空滤波方法,在规定阈值下将滤波区域自适应分为若干个子区域,进行共模误差的提取和去除。对陆态网184个GNSS站点垂向坐标序列进行时空滤波,3组随机实验中,自适应PCA时空滤波后的站点序列平均RMS值减少约39.7%、38.4%和39.7%,且优于整体PCA滤波。进一步分析滤波前后站点噪声特性变化,结果显示,相比于整体PCA滤波,自适应滤波方法中站点残差序列幂律噪声减少约17.8%。 展开更多
关键词 GNSS坐标时间序列 大尺度区域 PCA 自适应时空滤波
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区域尺度地埋管地源热泵与能源地下结构开采浅层地热能评价综述
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作者 孔纲强 常洪林 +1 位作者 王天赐 杨庆 《岩土力学》 EI CAS CSCD 北大核心 2024年第5期1265-1283,共19页
随着浅层地热能的大规模开发利用,针对地埋管地源热泵和能源地下结构的研究正由单个、单体尺度逐渐转向区域尺度。相较于地埋管地源热泵,能源地下结构占地面积小、成本低,在大规模城市建设及地下空间开发中具有良好的优势。从热物性参... 随着浅层地热能的大规模开发利用,针对地埋管地源热泵和能源地下结构的研究正由单个、单体尺度逐渐转向区域尺度。相较于地埋管地源热泵,能源地下结构占地面积小、成本低,在大规模城市建设及地下空间开发中具有良好的优势。从热物性参数和地下城市热岛效应两方面总结浅层地热能理论潜力现有研究成果,简述浅层地热能的开发形式,重点针对区域尺度地埋管地源热泵与能源地下结构的适应性评价进行系统综述,从适宜性分区、热交换潜力、满足建筑物能源需求效果三方面建立相应的区域尺度能源地下结构评价体系,以我国山东临朐县和德国巴登-符腾堡州地埋管地源热泵及我国南京大学仙林校区能量桩的区域性研究为案例进行深入分析,归纳当前研究中存在的问题,并对区域尺度能源地下结构的下一步研究进行展望。 展开更多
关键词 地埋管地源热泵 能源地下结构 浅层地热能 区域尺度 评价
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长三角地区医疗卫生资源供给的时空演化特征及其影响因素 被引量:1
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作者 陈玉娟 王志斌 +2 位作者 周启俊 瞿建平 陈加正 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2024年第1期76-89,共14页
在健康中国与长三角区域一体化发展国家战略的目标驱使下,医疗卫生资源供给能力日渐成为区域公共设施均等化发展的重要指标,新型冠状病毒肺炎疫情等突发公共卫生事件对地区医疗卫生资源供给能力提出了更高的要求。为辨明长三角地区医疗... 在健康中国与长三角区域一体化发展国家战略的目标驱使下,医疗卫生资源供给能力日渐成为区域公共设施均等化发展的重要指标,新型冠状病毒肺炎疫情等突发公共卫生事件对地区医疗卫生资源供给能力提出了更高的要求。为辨明长三角地区医疗卫生资源供给的发展特征与影响因素,构建了以时间演变、空间分异与因子探究为主的分析结构,采用泰尔指数、空间自相关、多尺度地理加权回归等方法,研究了2001—2019年长三角地区41个城市医疗卫生资源供给的区域差异与影响因素。结果表明,研究期内长三角地区医疗卫生资源增长迅速,区域均衡性提高;总体格局与长三角“Z”字形空间结构相吻合;医疗卫生资源供给的影响因素涵盖社会、经济与政治3个维度,且作用强度存在空间异质性。在此基础上,提出了促进长三角地区医疗服务一体化发展的对策及建议。 展开更多
关键词 医疗卫生资源 区域差异 多尺度地理加权回归 长三角地区
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Large-scale Migration of Fluids toward Foreland Basins during Collisional Orogeny: Evidence from Triassic Anhydrock Sequences and Regional Alteration in the Middle-Lower Yangtze Area 被引量:3
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作者 HOUZengqian YANGZhusen LIYinqing ZENGPusheng MENGYifeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期203-220,共18页
The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large dist... The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large distinctive Cu-Fe-Au metallogenic belt. In the tectonic evolution, large-scale migration and convergence of fluids toward foreland basins induced during the collisional orogeny of the Yangtze and North China continental blocks were of vital importance for the formation of the metallogenic belt. Through geological surveys of the middle-lower Yangtze area, three lines of evidence of large-scale fluid migration are proposed: (1) The extensive dolomitic and silicic alteration penetrating Cambrian-Triassic strata generally occurs in a region sandwiched between the metallogenic belt along the Yangtze River and the Dabie orogenic belt, and in the alteration domain alternately strong and weak alteration zones extend in a NW direction and are controlled by the fault system of the Dabie orogenic belt; it might record the locus of the activities of long-distance migrating fluids. (2) The textures and structures of very thick Middle-Lower Triassic anhydrock sequences in restricted basins along the river reveal the important contribution of the convergence of regional hot brine in restricted basins and the chemical deposition or their formation. (3) Early-Middle Triassic syndepositional iron carbonate sequences and Fe-Cu-Pb-Zn massive sulfide deposits alternate with anhydrock sequences or are separated from the latter, but all of them occur in the same stratigraphic horizon and are intimately associated with each other, being the product of syndeposition of high-salinity hot brine. According to the geological surveys, combined with previous data, the authors propose a conceptual model of fluid migration-convergence and mineralization during the Dabie collisional orogeny. 展开更多
关键词 large-scale migration of fluids collisional orogeny anhydrock sequence regional alteration middle-lower Yangtze River
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