Spatial optimization of rural settlement relocation by incorporating inter‐village social connections under future policy scenarios

Social connections between villages can represent farmers’ interests and thus benefit participatory rural relocation planning. With rural development, however, these connections will change and may weaken the adaptation of relocation plans to future rural systems. As yet, most studies still use empirical social connections to guide relocation planning, while a few have incorporated predicted connections in the context of rural development into relocation decisions. Meanwhile, spatial optimization approaches have seldom been adopted to solve this geographical decision issue. Accordingly, our study proposes a novel spatial relocation framework that incorporates changed inter‐village social connections under future rural development scenarios. Empirical inter‐village connections and their policy‐induced changes in central China were explored using social network analysis. An integration of particle swarm optimization and geographic information systems was adopted to identify the relocation solutions with maximum inter‐village connections and maximum spatial land use compactness, and to examine how connection changes under different policy scenarios influenced relocation outcomes. The results demonstrate the significance of incorporating policy‐induced social connections into relocation plans, and most importantly, show the negative relations between changed social connections and the migration distance/direction of relocated settlements. Our study is expected to improve the adaptation of relocation plans to future rural development.     

Decomposition analysis on direct material input and dematerialization of mining cities in Northeast China

Material dematerialization is a basic approach to reduce the pressure on the resources and environment and to realize the sustainable development. The material flow analysis and decomposition method are used to calculate the direct material input (DMI) of 14 typical mining cities in Northeast China in 1995-2004 and to analyze the demateri-alization and its driving factors in the different types of mining cities oriented by coal, petroleum, metallurgy and multi-resources. The results are as follows: 1) from 1995 to 2006, the increase rates of the DMI and the material input intensity of mining cities declined following the order of multi-resources, metallurgy, coal, and petroleum cities, and the material utilizing efficiency did following the order of petroleum, coal, metallurgy, and multi-resources cities; 2) during the research period, all the kinds of mining cities were in the situation of weak sustainable development in most years; 3) the pressure on resources and environment in the multi-resources cities was the most serious; 4) the petro-leum cities showed the strong trend of sustainable development; and 5) in recent years, the driving function of eco-nomic development for material consuming has continuously strengthened and the controlling function of material utilizing efficiency for it has weakened. The key approaches to promote the development of circular economy of min-ing cities in Northeast China are put forward in the following aspects: 1) to strengthen the research and development of the technique of resources' cycling utilization, 2) to improve the utilizing efficiency of resources, and 3) to carry out the auditing system of resources utilization.     

北黄海温盐分布季节变化特征分析

利用2006～2007年夏冬春秋4个季节北黄海的大面调查资料,分析了4个季节北黄海温度和盐度大面以及典型断面分布特征,得出以下结论:2007年冷水团势力范围强于2006年,北黄海冷水团的形成受地形影响.黄海暖流冬春季较强,冬季最强,夏季最弱,秋季开始形成.鲁北沿岸流冬季最强,春季减弱,夏秋季消失,但夏季鲁北沿岸存在冬季鲁北沿岸流水的残余体,即鲁北沿岸水.辽南沿岸水4个季节都以低盐为特征,除夏季低盐中心位于庄河口外,其它3个季节低盐中心均位于调查区域的东北角.渤海与北黄海之间的水交换4个季节都存在.春季,断面盐跃层形成滞后于温跃层;秋季,断面盐跃层消失滞后于温跃层.     

云参数法干旱遥感监测模型的完善

在原有的云参数法干旱遥感监测模型的基础上,对云参数进行时间空间修正,得到了具有时间空间普适性的新型云参数法干旱遥感监测模型.首先分析了云参数随时空变化的规律即云参数影响函数,并分析确定修正函教的函数形式,然后联合遥感数据和同步地面实测20 cm深度土壤湿度数据确定修正函数,最后通过定权方式确定改进型干旱遥感监测模型.利用FY-2C数据进行了全国范围干旱遥感监测实验,同时与传统方法的监测结果进行对比分析,认为新型模型对空间时间大尺度条件下的干旱监测结果更准确可信.     

利用南极走航观测评估卫星遥感海表面温度

利用1989-2005年间南极走航观测的海表面温度,对目前3个主要的卫星反演的SST产品AVHRR(Advanced Very High Resolution Radiometer),TMI(TRMM Microwave Imager)和AMSR-E(Advanced Microwave Scanning Radiometer for the Earth Observing System)进行了较为系统的评估,并着重检验了它们在南大洋的准确性.结果表明,AVHRR SST比观测数据偏冷,白天的偏差为-0.12℃,夜晚的偏差为-0.04℃,而且南大洋的冷偏差更为显著.TMI SST比观测数据明显偏暖,白天的偏差为0.48℃,夜晚的偏差为0.57℃,其温差ΔT受37GHz风速影响,在强风速(>6m/s)下这种影响仍然存在.AMSR-ESST比观测数据偏暖,白天的偏差为0.34℃,夜晚的偏差为0.27℃,而且南大洋的暖偏差相对较大.AMSR-E SST温差受水汽影响,并在南大洋随着水汽的增加而增加.通过进一步比较微波(AMSR-E和TMI)和红外(AVHRR)遥感的SST在2004年北半球冬季(即南半球夏季)的差别,发现微波遥感在热带(15°S-15°N)和南大洋区域(45°S以南)比红外遥感偏暖,而且在南大洋区域的偏差相对较大,相反在北半球中纬度区域(15°~40°N)偏冷.AMSR-E与AVHRR SST的温差,从白天到夜晚有减小的趋势,而TMI与AVHRR SST的温差无明显的变化.     

汕尾风暴潮频率与海堤改造初探

通过研究1970-2005年间汕尾港遭受风暴潮袭击的程度,对汕尾港风暴潮增水情况进行分析,用Pearson-Ⅲ分布和Gumbel分布两种概率统计方法分别对汕尾港不同重现期潮位值进行推算,并以此为基础结合走访相关单位和实地踏勘收集汕尾海堤历史和现状资料、风暴潮频率和海平面变化情况等,运用海堤工程设计防潮相关标准探讨汕尾已建海堤存在的问题,并针对性地提出改造建议,为汕尾市海堤的修复加固和管理提供参考.     

一种新的聚焦点不同的近景影像融合方法

近景摄影测量是实现地面目标高精度三维建模的主要方法之一。实际摄影测量过程中,普通数字摄像机在拍摄与镜头距离不同的多个目标时,无法同时聚焦到所有目标而使近景影像各处都清晰。本文以不同聚焦点近景影像的融合为研究内容,以图像一层小波分解的高频系数能量为影像清晰度衡量指标。通过计算小波影像能量,将整幅影像划分为清晰区域、模糊区域及二者的交界区域。对于清晰区域和模糊区域,将清晰区域的像元值直接应用于融合影像,而对于二者的交界区域,将curvelet变换所得初始融合影像的像元值应用于对应位置处的融合影像,从而得到融合影像。最后,用两组实例数据对融合方法进行了验证,并采用信息熵、均方根误差和峰值信噪比三种客观评价准则,对所得融合影像进行定量分析。     

利用双阳台水管观测资料检测地球自由振荡

基于双阳台水管倾斜仪的数字化观测资料,利用功率谱密度估计方法,在没有对资料进行去固体潮处理的情况下,准确获得了2004年12月26日苏门答腊大地震激发的0S3～0S31基频球型自由振荡。并与PREM模型的理论自由振荡周期进行了对比,发现实测振荡周期与PREM预测的振荡周期相吻合,除0S3、0S4振型的观测周期和PREM模型理论周期的相对误差大于0.3%外,其他振型的观测周期和PREM模型理论周期的相对误差大都集中在0.1%左右。同时还检测到了5个谐频球型振荡和8个环型振荡。     

时间选择性衰落信道下的差分空时多普勒编码

对于差分编码的系统,接收端可利用差分编码自身的结构来进行解调,无需知道信道状态信息.因此基于时间选择性衰落信道的基扩展模型,提出一种新型的应用于时间选择性衰落信道下多输入多输出系统的差分空时多普勒(DSTD)编码方案,由该方案组成的系统可以配备任意数目的发送和接收天线.该DSTD系统发送端由频谱编码器、差分编码器和OFDM调制器串联组成,能提供最大空间-多普勒分集增益和显著的编码增益.差分编码器中酉结构的引入可以实现线性空时分离的最大似然检测,降低了译码的复杂度.仿真分析表明与已有差分系统相比,文中所提出的差分编码方案可以获得更高的分集增益.     

Analysis of types and changes of village-level economy in rural Gongyi city,Henan Province since 1990

Based on the research on the rural living standard in China in terms of annual net income per capita, we define six types of village-level economy, i.e. ＂to be extremely poor＂, ＂to make a basic living＂, ＂to dress warmly and eat one＇s fill＂, ＂to try to enrich （to disengage poverty）＂, ＂to be well-off＂ and ＂to be affluent＂. The data of average annual net income of all the 292 villages between 1990 and 2004 in rural Gongyi City, Henan Province were collected, verified and classified. By using standard deviation, coefficient of variation and regression analysis, it is found that the Gongyi＇s rural economy has boosted up remarkably from the relative-poverty and absolute-poverty stages in 1990 to the well-off in 2004. However, the absolute differences between villages present a trend of enlargement, while the relative differences fluctuating. On the other hand, spatial analysis of village-level economy shows that most villages with relatively high economic development level were located along national expressway and most villages with absolute-poverty lay in remote mountainous areas in 1990. Since the 1990s, the rapid urbanization and industrialization have had strongly positive effects on rural economic growth. Initial economic foundation, natural resources and traditional techniques also contribute to village economy. From the perspective of geography, villages with location advantages, such as near urban center or industrial parks, have more chances for their economic development and the ＂core-periphery＂ economic structure has been presented in the process of rural development.