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基于精灵4RTK的无人机测绘技术在房产分丘平面图测绘中的应用
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作者 付夭霞 《中文科技期刊数据库(全文版)工程技术》 2024年第11期138-141,共4页
随着测绘技术的快速发展,传统测绘技术周期较长、成本高、受野外环境影响大的缺点逐渐显现出来,难以满足实际生产需要。本文详细阐述了无人机测绘技术在房产分丘平面图测绘中的优势,大大提高了工作效率,并结合精灵4-RTK无人机测绘技术... 随着测绘技术的快速发展,传统测绘技术周期较长、成本高、受野外环境影响大的缺点逐渐显现出来,难以满足实际生产需要。本文详细阐述了无人机测绘技术在房产分丘平面图测绘中的优势,大大提高了工作效率,并结合精灵4-RTK无人机测绘技术在房产分丘平面图中的应用实例,总结了精灵4-RTK无人机测绘房产分丘平面图的技术路线、精度分析等。本文的工作,对无人机测绘技术在房产分丘平面图的测绘应用具有较好的指导意义。 展开更多
关键词 基于精灵4-RTK 无人机 房产测绘 分丘平面图 应用实例
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房产分丘及用地类型划分的探讨
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作者 徐广翔 《矿山测量》 2003年第4期46-47,共2页
现行分丘与编号方法不能准确反映房产用地类型 ,所以在实际工作中很难把握。根据房产管理工作的需要 ,文中提出了在建筑物测图中表示用地类型的分丘编号方法。
关键词 分丘 房产 编号 建筑物
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房产分幅图测绘中两个问题的探讨
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作者 赵喜江 徐广翔 《黑龙江矿业学院学报》 2000年第4期50-51,55,共3页
现行分丘与编号方法存在不能准确反映房产用地类型信息、丘的划分方法很难把握等问题,根据房产管理工作的需要,提出了在建筑物上表示用地信息的分丘编号方法。
关键词 分丘 房产幅图 测绘 用地类型 房地产
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Effect of Slow and Controlled Release Fertilizers on the Yield and Nutrient Use Efficiency of Hot Pepper in Qiu-bei 被引量:8
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作者 杜彩艳 段宗颜 +2 位作者 鲁耀 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第5期761-764,共4页
[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei ho... [Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper(Capsicum frutescens L.)as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection. 展开更多
关键词 Slow and controlled release fertilizer Qiubei hot pepper YIELD Nutrient use efficiency
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Characteristics of Soil Porosity and Changes of Soil Water Content in Eucalyptus Plantation 被引量:1
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作者 熊柳梅 黄金生 +7 位作者 曾艳 黄雁飞 陈桂芬 刘永贤 周柳强 谭宏伟 黄美福 黄玉溢 《Agricultural Science & Technology》 CAS 2015年第4期662-667,共6页
Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for ... Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer (A), iI uvial horizon (B) and parent material horizon (C) in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences (P&gt;0.05) among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy (P&lt;0.05) among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands. 展开更多
关键词 Eucalyptus plantatlon Soil porosity Changes of soil water content Red soli Hilly reglon South China
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Effects of Combined Application of Water Retaining Agents and Organic Materials on Water Holding Characteristics of Yellow Brown Soils in Hilly Areas 被引量:1
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作者 唐玉邦 虞利俊 +4 位作者 徐磊 罗佳 王东升 范如芹 裴勤 《Agricultural Science & Technology》 CAS 2015年第9期1985-1988,共4页
[Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of comple... [Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of complex water-holding organic materials was determined by multi-factor mixture experiment and the curve changes of soil moisture characters were tested to analyze water-holding capacity and water availability of soils. [Result] The initial moisture content of soil with different mixture proportions improved in varying degrees. For example, when water-retention agents reached 0.4% and 0.6% of soil weight, soil moisture contents were 69.0% and70.5%, respectively, which showed significant differences with the control(S0.0). Soil dehydration terms in different treatments all extended, prolonging in the range of4.6-14 d. [Conclusion] The applications of water-retention agent and organic material would improve water-holding capacity of hills and low mountains, and initial moisture content and dehydration cycle tend to be volatile upon mixture proportion. Therefore,it is necessary to adjust soil fertility, crop species, and irrigation to meet crop demands on fertilizer and water. 展开更多
关键词 Water retaining agents Organic materials Soils of hilly areas Water characteristics
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小资料
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《价格月刊》 1983年第17期16-16,共1页
关键词 资料室 年平均 国民收入 财政收入 时期 分丘 比例 奖金 发放 金额
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甜甜山歌传传情
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作者 吴才泽 《歌海》 2001年第11期47-47,共1页
关键词 山歌 广西 歌手 断口 刘三姐 分丘 石台 同班 直头 声乐
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Response of Ecosystem Service Value Based on Land Use Changes and Analysis of its Driving Factors in Typical Hilly Region with Red Soil 被引量:6
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作者 邹金浪 王金政 +1 位作者 王鹏 乐文年 《Agricultural Science & Technology》 CAS 2010年第11期150-154,共5页
The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation w... The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation was employed to explore the contribution level of the indicators such as total population,urbanization level,proportion of primary industry and investment of social fixed assets on ecosystem service value,and the correlation analysis was also carried out.The results showed that the ecosystem service value in Xingguo County during 1996-2005 mainly was woodland,and the decrease of woodland area was the major reason for the sustained reduction of ecosystem service value.With the further increase of market demand and the incentives of local government,the garden area rapidly increased during 2001-2005,and the influence degree of garden towards the changes of ecosystem service value was only second to woodland,ranking No.2.Four socio-economic indicators had different correlation degree with ecosystem service value during the different research periods.Total population,urbanization level and proportion of primary industry had high correlation degree with ecosystem service value,whereas the influence degree of various socio-economic indicators on ecosystem service value was equal with each other day by day.Urbanization level,investment of social fixed assets and total population had significant negative correlation with ecosystem service value,while the proportion of primary industry had positive correlation with ecosystem service value. 展开更多
关键词 Ecosystem service value Land use change Gray correlation analysis Driving factor Hilly region with red soil
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房产图测绘工作的思考
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作者 谭英 《重庆国土房产》 2004年第2期28-29,共2页
房产图是房屋产权、产籍管理的基本资料,按房产管理需要,分为房产分幅平面图(分幅图)、房产分丘平面图(分丘图)和房屋分层分户平面图(分户图)。分幅图是全面反映房屋及其用地的位置、面积和权属等状况的基本图。一般先测绘分幅图,然... 房产图是房屋产权、产籍管理的基本资料,按房产管理需要,分为房产分幅平面图(分幅图)、房产分丘平面图(分丘图)和房屋分层分户平面图(分户图)。分幅图是全面反映房屋及其用地的位置、面积和权属等状况的基本图。一般先测绘分幅图,然后据此测绘或绘制分丘图和分户图。 展开更多
关键词 房产图 测绘工作 房产幅平面图 房产分丘平面图 房屋户平面图
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DNA Damage and Repair of Two Ecotypes of Phragmites communis Subjected to Water Stress 被引量:3
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作者 王俊刚 张承烈 《Acta Botanica Sinica》 CSCD 2001年第5期490-494,共5页
In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence... In order to thoroughly understand the mechanism Of drought resistance in plants at DNA level, the DNA damage of two ecotypes of reeds (Phragmites communis T.) stressed by PEG 6000 was analyzed by means of fluorescence analysis of DNA unwinding (FADU). The results showed that the residual double strand DNA percentages (dsDNA%) in dune reed (DR) were significantly higher than those in swamp reed (SR) treated with either 20% or 30% PEG 6000. This meant that the DNA of DR was less damaged in comparison with SR. Similarly, DR resisted DNA damage more strongly than SR as reactive oxygen species (ROS) increased by adding ROS producers diethyldithio carbamate (DDC), H2O2 and Fe2+ of different concentrations. Meanwhile, treating PEG stressed SR with ROS scavengers such as dimethyl sulphoxide (DMSO) and ascorbic acid (Vc) resulted in the reduction of DNA damage, suggesting that ROS could cause DNA damage. In addition, the DNA repair for water-stressed reeds indicated that DR repaired DNA damage much faster and more completely. This might be the first indication that drought stress led to DNA damage in plants and that drought resistance of plants was closely related to DNA damage and repair. 展开更多
关键词 dune reed swamp reed water stress reactive oxygen species DNA damage of plants in vivo DNA repair
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Minimally invasive thalamic hematoma drainage can improve the six-month outcome of thalamic hemorrhage 被引量:8
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作者 Wen-Ming LIU Xue-Guang ZHANG +2 位作者 Ze-Li ZHANG Gang LI Qi-Bing HUANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第4期266-273,共8页
Objective To explore predictors of the 6-month clinical outcome ofthalamic hemorrhage, and evaluate if minimally invasive thalamic hematoma drainage (THD) could improve its prognosis. Methods A total of 54 patients ... Objective To explore predictors of the 6-month clinical outcome ofthalamic hemorrhage, and evaluate if minimally invasive thalamic hematoma drainage (THD) could improve its prognosis. Methods A total of 54 patients with spontaneous thalamic hemorrhage were evaluated retrospectively. Clinical data, including demographics, stroke risk factors, neuroimaging variables, Glasgow Coma Score (GCS) on admission, surgical strategy, and outcome, were collected. Clinical outcome was assessed using a modified Rankin Scale, six months after onset. Univariate analysis and multivariate logistic regression analysis were performed to determine predictors of a poor outcome. Results Conservative treatnaent was performed for five patients (9.3%), external ventricular drainage (EVD) for 20 patients (37.0%), THD for four patients (7.4%), and EVD combined with THD for 25 patients (46.3%). At six months after onset, 21 (38.9%) patients achieved a favorable outcome, while 33 (61.1%) had a poor outcome. In the univariate analysis, predictors of poor 6-month outcome were lower GCS on admis- sion (P = 0.001), larger hematoma volume (P 〈 0.001), midline shift (P = 0.035), acute hydrocephalus (P = 0.039), and no THD (P = 0.037). The independent predictors of poor outcome, according to the multivariate logistic regression analysis, were no THD and larger hematoma volume. Conclusions Minimally invasive THD, which removes most of the hematoma within a few days, with limited damage to perihematomal brain tissue, improved the 6-month outcome of thalamic hemorrhage. Thus, THD can be widely applied to treat patients with thalamic hemorrhage. 展开更多
关键词 Hematoma volume Minimally invasive OUTCOME PREDICTOR Thalamic hematoma drainage Thalamic hemorrhage
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Zonal Distribution of the Erosion-Landslide and Soil Micromorphological Features in Purple Hilly Region 被引量:6
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作者 HEYurong LIAOChaolin XUPei ZHANGBaohua 《Journal of Mountain Science》 SCIE CSCD 2005年第1期42-49,共8页
In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, so... In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1) According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion–landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphological features of slide soil. 展开更多
关键词 Purple hilly region erosion-landslide zonal distribution soil micromorphology
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Spatial Differentiation of Elements in Soils on Red-Earthy Hill Landscape of Central China 被引量:1
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作者 CHENZHI-CHENG ZHAOWEN-JUN 《Pedosphere》 SCIE CAS CSCD 1991年第2期127-136,共10页
Samples of 21 soil profiles and 165 top soils from an area of approximate 1.5km^2 on red-earthy hill landscape were collected and analysed.The content of Ca,Mg,K,P,Fe,Mn,Zn and Cu in soils relate with the kind of pare... Samples of 21 soil profiles and 165 top soils from an area of approximate 1.5km^2 on red-earthy hill landscape were collected and analysed.The content of Ca,Mg,K,P,Fe,Mn,Zn and Cu in soils relate with the kind of parent material and the position of topography,however,there is great variation due to the local difference of the form of soil utilization.From the difference in spatial distribution of elements content,it is believed that eight kinds of elements are lost by chemical leaching and physical translocation,meanwhile some are added (such as Ca,P,K,Mg) and some mobilized (such as Fe,Mn,Zn,Cu and P) through cultivation,fertilization and irrigation in the soils on the landscape investigated.The sectional differentiation in abundance or deficiency of elements in top soils on the landscape investigated is distinct,which is important for carrying out agricultural management and reasonable fertilization according to local conditions. 展开更多
关键词 contents of Ca Mg K P Fe Mn Zn and Cu geochemical behavior sectional differentiation
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The runoff characteristics and harmonic analysis of the soil moisture dynamics in Robinia pseudoacacia stand 被引量:1
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作者 高鹏 刘作新 陈伏生 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期295-298,共4页
Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the wes... Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion. 展开更多
关键词 Hilly semi-arid area Robinia pseudoacacia stand Runoff generation characteristics Soil moisture dynamics Harmonic analysis
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Tourism resource assessment and spatial analysis of wine tourism development: a case study of the eastern foothills of China's Helan Mountains 被引量:10
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作者 WANG Lei LIU Jia-ming +2 位作者 WANG Ling-en ZHU He LIN Jing 《Journal of Mountain Science》 SCIE CSCD 2018年第3期645-656,共12页
The reasonable development and utilization of mountainous regions closely relates to local economic development and ecological security. The wine production region in the eastern foothills of the Helan Mountains in Ni... The reasonable development and utilization of mountainous regions closely relates to local economic development and ecological security. The wine production region in the eastern foothills of the Helan Mountains in Ningxia, Ningxia Hui Autonomous Region, with its excellent terroir, is emerging as one of China's three major geographical attractions. Based on surveys of tourism resources and spatial analysis for this wine producing region, we propose a highly representative and practicable path for wine tourism development. Based on China's national standard in Classification, Investigation and Evaluation of Tourism Resources(GB/T 18972-2003), which recommended the types and grades of tourism resources in one area, we conduct an analysis of resource characteristics and the current state of development. Using Arc GIS software, spatialautocorrelation analysis, average nearest neighbor analysis, as well as clustering and outlier analysis, we are able to derive the spatial distribution characteristics of tourism resources. Our survey showed that tourism resources in this area are relatively abundant and have good quality and clear combination advantages. Nonetheless, there are resources shortage for wine tourism and poor integration of wine production with the tourism industry. Regarding the spatial distribution of resources, we revealed the current states of and issues surrounding regions with concentrated resources, as well as characteristics of this clustering. Finally, we proposed a development path for wine tourism in this region based on the five dimensions of management mode, industrial path, product development, spatial optimization, and market development. 展开更多
关键词 Development path Helan Mountains Resource assessment Wine tourism
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An Object-based Approach for Two-level Gully Feature Mapping Using High-resolution DEM and Imagery: A Case Study on Hilly Loess Plateau Region, China 被引量:12
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作者 LIU Kai DING Hu +4 位作者 TANG Guoan ZHU A-Xing YANG Xin JIANG Sheng CAO Jianjun 《Chinese Geographical Science》 SCIE CSCD 2017年第3期415-430,共16页
Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) a... Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) and remote sensing imagery, combined with developed object-based methods enables automatic gully feature mapping. But still few studies have specifically focused on gully feature mapping on different scales. In this study, an object-based approach to two-level gully feature mapping, including gully-affected areas and bank gullies, was developed and tested on 1-m DEM and Worldview-3 imagery of a catchment in the Chinese Loess Plateau. The methodology includes a sequence of data preparation, image segmentation, metric calculation, and random forest based classification. The results of the two-level mapping were based on a random forest model after investigating the effects of feature selection and class-imbalance problem. Results show that the segmentation strategy adopted in this paper which considers the topographic information and optimal parameter combination can improve the segmentation results. The distribution of the gully-affected area is closely related to topographic information, however, the spectral features are more dominant for bank gully mapping. The highest overall accuracy of the gully-affected area mapping was 93.06% with four topographic features. The highest overall accuracy of bank gully mapping is 78.5% when all features are adopted. The proposed approach is a creditable option for hierarchical mapping of gully feature information, which is suitable for the application in hily Loess Plateau region. 展开更多
关键词 object-based image analysis gully feature hierarchical mapping gully erosion Digital Elevation Model(DEM)
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The characteristics of gully erosion over rolling hilly black soil areas of Northeast China 被引量:6
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作者 胡刚 伍永秋 +3 位作者 刘宝元 张永光 游智敏 于章涛 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期309-320,共12页
In this study,short-term gully retreat was monitored from the active gullies selected in representative black soil area,using differential global positioning system(GPS).With the support of geographic information syst... In this study,short-term gully retreat was monitored from the active gullies selected in representative black soil area,using differential global positioning system(GPS).With the support of geographic information system(GIS),multi-temporal digital elevation models(DEM) were constructed from the data collected by GPS and used for further analysis.Based on the analysis of multi-temporal DEM,we discussed the erosion-deposition characteristics within gully and a developing model for black soil gully area of Northeast China was proposed.The results are:(1) The analysis of the monitored gully data in 2004 indicated that the retreat of gully head reached more than 10 m,gully area extended 170-400 m2,net gully eroded volume 220-320 m3,and gully erosion modulus 2200-4800 t?km?2?a?1.(2) Compared with the mature gully the initial gully grows rapidly,and its erosion parameters are relatively large.The erosion parameters have not only to do with flow energy,but also with the growth phase.(3) There are significant seasonal differences in gully erosion parameters.The extension of gully area and width dominates in winter and spring without marked net erosion while changes mainly occur in gully head and net erosion in rainy season.(4) It is remarkable for freeze-thaw erosion in the black soil area of NE China.The gully wall of SG2 extended 0.45 m under freeze-thaw effect in 2004,and the distance of gully head retreated maximally 6.4 m.(5) Due to freeze-thaw action and snowmelt,gully is primarily in the interior adjustment process in winter and early spring.There are much more depositions compared with that during rainy season,which can almost happen throughout the gully,while erosion mostly occurs near head,esp.for gullies having a relatively long history of development.On the other hand,the process of energy exchange with exterior dominates in rainy season.It is considered that this cyclic process is an important mechanism for gully growth in high latitude or/and high attitude regions. 展开更多
关键词 rolling hilly black soil areas gully erosion digital terrain model global positioning system
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Numerical Investigation on Power Outputs of a Wind Turbine Sited over Continuous Hilly Terrain
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作者 ZHOU Tianyi TAN Jianfeng +2 位作者 CAI Jiangang SHI Ruipeng XIA Yunsong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第1期120-128,共9页
The location of wind turbines on a continuous hilly terrain has an influence on its power outputs.A CFDbased approach is developed to investigate the complex aerodynamic interference between two wind turbines and the ... The location of wind turbines on a continuous hilly terrain has an influence on its power outputs.A CFDbased approach is developed to investigate the complex aerodynamic interference between two wind turbines and the hilly terrain.In this approach,a new three-dimensional model of hilly terrain is established to analyze its viscous effect,and a wind shear is modelled through logarithmic function.They are coupled into the aerodynamics of wind turbine based on“FLUENT”software.Then we apply the proposed method to the NREL Phase VI wind turbines and compare with an experiment in the atmospheric boundary layer(ABL)wind tunnel to validate its accuracy.The simulation also investigates the power outputs of wind turbines on the flat ground and the continuous hilly terrain by changing the location of the wind turbine related to the hilly terrain and the shape of the 1st hill.The results show that the wind turbine located on the top of the 2nd hill has the maximum power;and that when the wind turbine is located on the downstream of the hill,the stall zone should be avoided,and the power of the wind turbine located on the side of the hill is higher than that of the wind turbine located on the front and rear of the hilly terrain. 展开更多
关键词 power characteristics wind shear function NREL wind turbine continuous hilly terrain simulation analysis
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Identifying Scale-location Specific Control on Vegetation Distribution in Mountain-hill Region 被引量:3
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作者 QIU Bing-wen ZENG Can-ying +2 位作者 TANG Zheng-hong LI Wei-jiao Aaron HIRSH 《Journal of Mountain Science》 SCIE CSCD 2013年第4期541-552,共12页
vegetation continuous The scale-location specific control on distribution was investigated through wavelet transforms approaches in subtropical mountain-hill region, Fujian, China. The Normalized Difference Vegetatio... vegetation continuous The scale-location specific control on distribution was investigated through wavelet transforms approaches in subtropical mountain-hill region, Fujian, China. The Normalized Difference Vegetation Index (NDVI) was calculated as an indicator of vegetation greenness using Chinese Environmental Disaster Reduction Satellite images along latitudinal and longitudinal transects. Four scales of variations were identified from the local wavelet spectrum of NDVI, with much stronger wavelet variances observed at larger scales. The characteristic scale of vegetation distribution within mountainous and hilly regions in Southeast China was around 20 km. Significantly strong wavelet coherency was generally examined in regions with very diverse topography, typically characterized as small mountains and hills fractured by rivers and residents. The continuous wavelet based approaches provided valuable insight on the hierarchical structure and its corresponding characteristic scales of ecosystems, which might be applied in defining proper levels in multilevel models and optimal bandwidths in Geographically Weighted Regression. 展开更多
关键词 NDVI Continuous wavelet transform Characteristic scale Mountain-hill region Scale-location specific
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