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Temporal and spatial changes of residential land in the Yuyang desert region of northern Shaanxi Province in recent 20 years

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Frontiers of Earth Science 2012年第3期6卷 250-260页

作者： xiangsheng yi Yanyu yiN Yaojie YUE Laboratory of Regional Geography School of Geography Beijing Normal University Beijing 100875 China Institute of Geographic-Sciences and-Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

It is very important to understand the temporal and spatial changes of residential land for the improvement of human settlement environment. Based on the three TM images of 1986, 1996 and 2005 and other assistant maps, the temporal and spatial characteristics of residential land in the Yuyang desert region of northern Shaanxi Province of China were analyzed by using geographical information System （GIS） and remote sensing （RS） technology. Some important conclusions were obtained, which mainly contained four aspects as follows. 1） The area of residential land in the Yuyang desert region increased 956.07 hm2 in total, and the changes of residential land among the townships were different with four various change trends. The expansion speeds in the Yuyang Township and Qinhe Township were the biggest from 1986 to 1996 and from 1996 to 2005, respectively. The expansion intensities in other townships were below 0.1%, except the Yuyang Township. 2） The number of residential land patches increased 2847, while the average area and perimeter of residential land patches decreased 0.304 hm2 and 60.78 m during 1986-2005, respectively. The residential land patches also displayed four different changes from 1986 to 2005 among the townships. 3） The residential land mainly distributed in the middle of Yuyang Township and Mahe Township, and the interface of Jinjitan Township and Mengjiawan Township. The total spatial pattern of residential land was relative stability, but the significant changes of residential land were found in the Yuyang Township and its vicinities during 1986-2005. 4） Three distribution patterns of residential land at the micro scale were categorized from the 100 typical villages in the study area. The number of villages in the pattern 1 increased, while the pattern 2 and pattern 3 decreased in recent 20 years, which implicated the adaptation of humans to the habitation environment. This research would provide scientific references fbr harmonizing the human-land r

关键词： residential land temporal change spatialpattern Yuyang desert region

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Pedotransfer Functions for Estimating Soil Bulk Density:A Case Study in the Three-River Headwater Region of Qinghai Province,China

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Pedosphere 2016年第3期26卷 362-373页

作者： yi xiangsheng LI Guosheng yiN Yanyu Agriculture Resource Monitoring Station Chinese Academy of Agricultural Engineering Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Bulk density(BD) is an important soil physical property and has significant effect on soil water conservation function. Indirect methods, which are called pedotransfer functions(PTFs), have replaced direct measurement and can acquire the missing data of BD during routine soil surveys. In this study, multiple linear regression(MLR) and artificial neuron network(ANN) methods were used to develop PTFs for predicting BD from soil organic carbon(OC), texture and depth in the Three-River Headwater region of Qinghai Province, China. The performances of the developed PTFs were compared with 14 published PTFs using four indexes, the mean error(ME), standard deviation error(SDE), root mean squared error(RMSE) and coefficient of determination(R^2). Results showed that the performances of published PTFs developed using exponential regression were better than those developed using linear regression from OC. Alexander(1980)-B, Alexander(1980)-A and Manrique and Jones(1991)-B PTFs, which had good predictions, could be applied for the soils in the study area. The PTFs developed using MLR(MLR-PTFs) and ANN(ANN-PTFs) had better soil BD predictions than most of published PTFs. The ANN-PTFs had better performances than the MLR-PTFs and their performances could be improved when soil texture and depth were added as predictor variables. The idea of developing PTFs for predicting soil BD in the study area could provide reference for other areas and the results could lay foundation for the estimation of soil water retention and carbon pool.

关键词：土壤容重青海省三江源区转换功能中国多元线性回归估算水源涵养功能

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Spatio-temporal variation of precipitation in the Three-River Headwater Region from 1961 to 2010

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Journal of Geographical Sciences 2013年第3期23卷 447-464页

作者： yi xiangsheng LI Guosheng yiN Yanyu Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

Based on a monthly dataset of precipitation time series （1961-2010） from 12 me- teorological stations across the Three-River Headwater Region （THRHR） of Qinghai Province China, the spatio-temporal variation and abrupt change analysis of precipitation were exam- ined by using moving average, linear regression, spline interpolation, the Mann-Kendall test and so on. Major conclusions were as follows. （1） The long-term annual and seasonal pre- cipitation in the study area indicated an increasing trend with some oscillations during 1961-2010; however, the summer precipitation in the Lantsang （Lancang） River Headwater Region （LARHR）, and the autumn precipitation in the Yangtze River Headwater Region （YERHR） of the THRHR decreased in the same period. （2） The amount of annual precipita- tion in the THRHR and its three sub-headwater regions was greater in the 1980s and 2000s. The springs were fairly wet after the 1970s, while the summers were relatively wet in the 1960s, 1980s and 2000s. In addition, the amount of precipitation in the autumn was greater in the 1970s and 1980s, but it was relatively less for the winter precipitation, except in the 1990s （3） The normal values of spring, summer, winter and annual precipitation in the THRHR and its three sub-headwater regions all increased, but the normal value of summer precipitation in the LARHR had a negative trend and the normal value of winter precipitation declined in general. （4） The spring and winter precipitation increased in most of the THRHR. The summer autumn and annual precipitation increased mainly in the marginal area of the west and north and decreased in the regions of Yushu, Zaduo, Jiuzhi and Banma. （5） The spring and winter precipitation in the THRHR and its three sub-headwater regions showed an abrupt change, except for the spring precipitation in the YARHR. The abrupt changes of spring precipitation were mainly in the late 1980s and early 1990s, while the abrupt changes of winter precipita- tion were primary

关键词： precipitation spatio-temporal variation abrupt change analysis Three-River Headwater Region

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Temperature variation and abrupt change analysis in the Three-River Headwaters Region during 1961-2010

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Journal of Geographical Sciences 2012年第3期22卷 451-469页

作者： yi xiangsheng Li Guosheng yin Yanyu Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China Beijing Normal Univ Sch Geog Beijing 100875 Peoples R China Beijing Normal Univ Key Lab Reg Geog Beijing 100875 Peoples R China

In this study, a monthly dataset of temperature time series （1961-2010） from 12 meteorological stations across the Three-River Headwater Region of Qinghai Province （THRHR） was used to analyze the climate change. The temperature variation and abrupt change analysis were examined by using moving average, linear regression, Spline interpolation, Mann-Kendall test and so on. Some important conclusions were obtained from this research, which mainly contained four aspects as follows. （1） There were several cold and warm fluctuations for the annual and seasonal average temperature in the THRHR and its three sub-headwater regions, but the temperature in these regions all had an obviously rising trend at the statistical significance level, especially after 2001. The spring, summer, autumn and annual average temperature increased evidently after the 1990s, and the winter average temperature exhibited an obvious upward trend after entering the 21st century. Except the standard value of spring temperature, the annual and seasonal temperature standard value in the THRHR and its three sub-headwater regions increased gradually, and the upward trend for the standard value of winter average temperature indicated significantly. （2） The tendency rate of annual average temperature in the THRHR was 0.36℃ 10a^-1, while the tendency rates in the Yellow River Headwater Region （YERHR）, Lancangjiang River Headwater Region （LARHR） and Yangtze River Headwater Region （YARHR） were 0.37℃ 10a^-1, 0.37℃ 10a^-1 and 0.34℃10a^-1 respectively. The temperature increased significantly in the south of Yushu County and the north of Nangqian County. The rising trends of temperature in winter and autumn were higher than the upward trends in spring and summer. （3） The abrupt changes of annual, summer, autumn and winter average temperature were found in the THRHR, LARHR and YARHR, and were detected for the summer and autumn average temperature in the YERHR. The abrupt changes of annual and summer average tempe

关键词： temperature variation inter-annual change inter-decadal change standard value change abruptchange analysis Three.River Headwaters Region

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水下盾构隧道管片拼装质量控制方法研究现状与展望

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隧道建设（中英文） 2024年第4期44卷 643-662页

作者：包小华李浚弘陈湘生沈俊刘自明姚义极端环境岩土和隧道工程智能建养全国重点实验室广东深圳518060 滨海城市韧性基础设施教育部重点实验室(深圳大学) 广东深圳518060 深圳大学土木与交通工程学院广东深圳518060 中铁二十二局集团深圳建设有限公司广东深圳518107

针对大型水下盾构隧道施工阶段可能存在的管片拼装质量问题,综述国内外相关水下盾构隧道管片拼装的重要研究,主要涵盖管片拼装质量控制指标、管片拼装对隧道衬砌力学性能的影响、管片拼装质量控制以及质量检测的应用等方面。针对管片拼... 详细信息

针对大型水下盾构隧道施工阶段可能存在的管片拼装质量问题,综述国内外相关水下盾构隧道管片拼装的重要研究,主要涵盖管片拼装质量控制指标、管片拼装对隧道衬砌力学性能的影响、管片拼装质量控制以及质量检测的应用等方面。针对管片拼装质量控制指标,探讨管片尺寸和几何要求、裂损性、水密性及防渗性能要求等关键内容。通过现场监测、相似模型试验与原型试验归纳管片拼装对水下盾构隧道衬砌力学性能的影响。在拼装质量控制方面,介绍管片拼装设备、盾构隧道管片传感监测系统、盾构姿态预测方法以及管片定位技术的发展和应用。同时,总结近期管片拼装缺陷检测方法的研究成果,包括三维激光扫描、图像三维重建以及计算机视觉等技术在管片衬砌裂缝及渗漏方面的应用。最后,讨论管片拼装的尚存问题以及研究趋势。目前存在的主要问题包括:1)缺乏有效的拼装质量实时监测与评估方法;2)对水下环境中管片拼装力学性能影响研究不足;3)自动化控制技术的成熟度不够;4)隧道缺陷检测精度及其风险评估方法仍需进一步优化。展望未来,将通过对管片拼装质量评估手段、自动化与智能化拼装技术以及高精度缺陷定量分析方法的不断创新和改进,实现对拼装质量的实时监测、数据分析和定量评估,从而提高管片拼装的效率、精度和安全性。

关键词：水下盾构隧道管片拼装质量控制指标力学特性质量检测

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农村土地承包经营权要素编码的关键问题及解决途径

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农业工程学报 2018年第14期34卷 257-262页

作者：易湘生裴志远赵虎郭琳胡华浪农业部耕地利用遥感重点实验室北京100125 农业部规划设计研究院农业资源监测站北京100125

为准确使用NY/T 2538-2014、规范农村土地承包经营权确权登记颁证工作,针对目前农村土地承包经营权要素编码中存在的县级段代码和乡级段代码编制、发包方编码、承包方编码、特殊区域编码等关键问题,采用文案调查法和实地调查法进行深入... 详细信息

为准确使用NY/T 2538-2014、规范农村土地承包经营权确权登记颁证工作,针对目前农村土地承包经营权要素编码中存在的县级段代码和乡级段代码编制、发包方编码、承包方编码、特殊区域编码等关键问题,采用文案调查法和实地调查法进行深入剖析,并给出了问题的解决途径。结果表明:1)县级段代码和乡级段代码应以目前正在开展的农村土地承包经营权确权登记颁证工作作为时间节点来进行编码,并采用民政部公布的行政区划代码;2)发包方应按照农村土地所有关系进行编码,并且发包方编码在承包期内保持稳定;3)承包方应视为权利人来进行编码,其编码取决于是否与发包方签订承包合同;4)农村土地承包经营权要素编码与特殊区域内农村土地承包管理方式无关,应按照农村土地承包经营权要素的内在关系进行编码。通过剖析上述关键问题,研究可进一步深化对农村土地承包经营权要素编码的认识,促进NY/T 2538-2014在农村土地承包经营权确权登记颁证工作中的规范应用。

关键词：土地利用农村地区土地承包经营权要素行政区划发包方承包方特殊区域

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基于GIS的武陵山区洪水灾害风险评估

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农业工程学报 2013年第24期29卷 110-117页

作者：殷洁裴志远陈曦炜易湘生孙丽农业部规划设计研究院北京100125

武陵山区是我国14个集中连片特困区之一,跨省交界面大、少数民族聚居多、贫困人口分布广,该区域内洪水灾害频发,使得"因灾致贫、因灾返贫"现象较为突出,对区域经济发展造成较大的阻力。本文基于灾害系统学原理,构建了适合区域成灾特点... 详细信息

武陵山区是我国14个集中连片特困区之一,跨省交界面大、少数民族聚居多、贫困人口分布广,该区域内洪水灾害频发,使得"因灾致贫、因灾返贫"现象较为突出,对区域经济发展造成较大的阻力。本文基于灾害系统学原理,构建了适合区域成灾特点的风险评估指标体系,采用风险评估模型,对武陵山区洪水灾害风险进行评估。研究结果表明:尽管区域洪灾易发,但承灾体脆弱性较低,致使武陵山区洪水灾害风险等级全区总体水平较低,高风险区呈东北-西南向条带状分布,从东南向西北,依次有:东南部的涟源市、冷水江市、新化县、隆回县、邵阳县、洞口县、武冈市高风险区;中部的石门-慈利-沅陵-芦溪-辰溪-溆浦-麻阳-芷江一线高风险区,西北部的丰都-石柱西北部高风险区。

关键词：洪水灾害风险评估 GIS 武陵山区

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基于GF-1影像的冬小麦种植面积核算及直补政策实施评价

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农业工程学报 2016年第18期32卷 169-174页

作者：马尚杰易湘生游炯郭琳娄径农业部规划设计研究院农业资源监测站北京100125 安徽省经济研究院合肥230001

粮食直接补贴政策的实施,对于促进粮食生产和农民增收、推动农业农村发展发挥了积极的作用。补贴资金发放的精准程度在一定程度上影响着财政资金的支农效率。该文拟研究基于卫星数据进行粮食直补政策落实效果评价的可行性。以安徽省濉... 详细信息

粮食直接补贴政策的实施,对于促进粮食生产和农民增收、推动农业农村发展发挥了积极的作用。补贴资金发放的精准程度在一定程度上影响着财政资金的支农效率。该文拟研究基于卫星数据进行粮食直补政策落实效果评价的可行性。以安徽省濉溪县为研究区,采用GF-1卫星16 m多光谱影像,在扣除线状地物、小地物的基础上,精准核算冬小麦种植面积。以乡镇为单位,比较统计发放面积与遥感核算面积,完成基于GF-1卫星数据的粮食补贴政策落实效果评价。结果表明:1)全县范围内,冬小麦直补发放统计面积与遥感核算面积较为吻合。直补发放统计面积为1 239.17 km^2,遥感核算面积为1 227.37 km^2,相对误差仅为0.96%;2)在乡镇尺度上,11个乡镇和1个开发区中共5个乡镇直补发放统计面积与遥感核算面积的相对误差<10%,8个乡镇<13%。相对误差最大的开发区、濉溪镇2个乡镇,以工商业用地为主,冬小麦种植面积少,地块零碎,遥感解译难度大。整体上,直补发放统计面积与遥感核算面积的Nash-Sutcliffe系数(Nash-Sutcliffe coefficient,ENS)为0.90,决定系数为0.93,两者相关程度较高。研究可为改进完善粮食补贴政策提供参考提供依据。

关键词：遥感粮食 GIS GF-1 粮食直补政策

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THE STUDY OF LATTICE MATCH IN GaInAsP/InP HETEROJUNCTION LPE LAYERS

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电子科学学刊(英文版) 1986年第1期3卷 76-81页

作者：杨易邬祥生李润身谭儒环李允平水海龙 Shanghai Institute of Metallurgy Academia Sinica Shanghai Institute of Metallurgy Academia Sinica

The effects of the growth conditions of two-phase solution liquid phase epitaxy(LPE)(*** temperature,cooling rates and solution composition)on lattice mismatch and band-gapwavelength in GaInAsP/InP heterojunction LPE layers have been investigated by X-ray double-crystal diffractometry and double-beam *** stress in the grown interface freeof misfit dislocations and lattice mismatch at growth temperature have been calculated.

关键词： diffractometry epitaxy mismatch prepare 半导体学报 narrow radius graded wafer analogous

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基于沙区土地功能分类的土地利用变化与模式研究——以陕北榆阳沙区为例

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北京师范大学学报（自然科学版） 2008年第4期44卷 439-443,F0003页

作者：易湘生王静爱岳耀杰北京师范大学地理学与遥感科学学院北京师范大学区域地理研究重点实验室北京100875

沙区作为典型的生态脆弱区,是土地利用研究的重点区域之一.选择陕北榆阳沙区,建立了沙区土地功能分类系统,基于多期遥感数据(1986年,1996年和2005年)和GIS空间分析方法,研究了该区的土地利用变化和土地利用模式.结果表明:榆阳沙区20年... 详细信息

沙区作为典型的生态脆弱区,是土地利用研究的重点区域之一.选择陕北榆阳沙区,建立了沙区土地功能分类系统,基于多期遥感数据(1986年,1996年和2005年)和GIS空间分析方法,研究了该区的土地利用变化和土地利用模式.结果表明:榆阳沙区20年来生产用地和生活用地面积增加,且生产用地增长幅度大于生活用地,生态用地比例略有减少但始终占绝对优势,生态环境状况整体好转;榆阳沙区存在自村中心向外依次为耕地-居民地灌草地夹杂分布-裸沙地、居民地耕地夹杂分布-灌草地-裸沙地和耕地-居民地-灌草地-裸沙地3种典型土地利用模式,且其安全性逐步变差.研究可为协调沙区土地利用与生态建设、创建环境友好型土地利用模式、构建良好人居环境提供科学依据.

关键词：土地功能分类土地利用变化模式榆阳沙区

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