单视SAR图像相干斑回波的特征分析与统计

高分辨率合成孔径雷达的相干斑是由雷达信号的干性引起的，并存在于所有相干图像中。根据SAR成橡机理，分析了产生的原因特征，给出了SAR相干斑的确切定义、统计方法。实验表明统计结果与传统方法相比更加精确。     

Far from Being "Home Alone": The Dynamics of Accompanied Fieldwork

Despite persistent images to the contrary, most fieldworkers are accompanied. Yet, there has been limited discussion on the nature of accompanied fieldwork, particularly by geographers. Drawing on our experiences in three countries in the tropics, we discuss the dynamics of being accompanied in “the field” by our children and female co‐researchers. Specifically, we focus on issues of access and rapport; the impacts of their presence on our positionality; and the implications these have for power relations and research outcomes. We demonstrate how being accompanied entangles our personal and professional selves and can result in more egalitarian power relations as we become “observers observed”. We argue that by paying attention to the dynamics of accompanied fieldwork, there is the potential to enhance the conceptual focus of our methodological concerns and to provide a more theoretically sophisticated mode of exploring the ways in which our multiple identities intersect while in “the field”.     

SEDIMENT TRANSPORT AND STREAM POWER

1 INTRODUCTION There are three basic energy dissipation rate approaches used for the derivation of sediment transport functions. They are the gravitational power theory by Velikanov (1954), the stream power theory by Bagnold (1966), and the unit stream power theory by Yang (1973, 1979, 1984, and 1986). The theoretical basis of these approaches has been summarized by Yang (1996) in his book, Sediment Transport Theory and Practice. Yang also made comparisons of the three basic approa…     

DEVELOPMENT AND APPLICATION OF AN EFFICIENT METHOD TO RIVER DISCHARGE MEASUREMENT

1 INTRODUCTION There are 129 rivers in Taiwan. Most of them are short and steep with small drainage basins and rapid flows. Heavy rains and flood flows usually carry large amount of sediment. The specific peak discharge (peak discharge per unit drainage area) in Taiwan has the highest value in the world. For example, the specific peak discharge of Wu River in central Taiwan is 10.5 cms/km2, which is about 618 times that of Yangtze River in China and 35 times that of Sinno River i…     

New anisotropic covariance models and estimation of anisotropic parameters based on the covariance tensor identity

 Many heterogeneous media and environmental processes are statistically anisotropic. In this paper we focus on range anisotropy, that is, stochastic processes with variograms that have direction dependent correlation lengths and direction independent sill. We distinguish between two classes of anisotropic covariance models: Class (A) models are reducible to isotropic after rotation and rescaling operations. Class (B) models can be separated into a product of one-dimensional functions oriented along the principal axes. We propose a new Class (A) model with multiscale properties that has applications in subsurface hydrology. We also present a family of Class (B) models based on non-Euclidean distance metrics that are generated by superellipsoidal functions. Next, we propose a new method for determining the orientation of the principal axes and the degree of anisotropy, i.e., the ratio(s) of the correlation lengths. This information reduces the degrees of freedom of anisotropic variograms and thus simplifies the estimation procedure. In particular, Class (A) models are reduced to isotropic and Class (B) models to one-dimensional functions. Our method is based on an explicit relation between the second-rank slope tensor (SRST), which can be estimated from the data, and the covariance tensor. The procedure is conceptually simple and numerically efficient. It is more accurate for regular (on-grid) data distributions, but it can also be used for sparse (off-grid) spatial distributions. In the case of non-differentiable random fields the method can be extended using generalized derivatives. We illustrate its implementation with numerical simulations.     

平面可视化技术对山东德南断裂系的精细识别

德南断裂带是山东德南洼陷的主要油气聚集场所 ,精细识别各断层的分布有重要的现实意义。将平面可视化技术应用于德南断裂的精细识别取得了很好的效果 ,已识别出德南断裂是一个向西散开的断裂系 ,它从北到南由 1、 2、 3号北倾断层组成 ;1、 2号断层最终汇聚为一条 ,2号断层下降盘发育 3～ 4条反向补偿断层 ;3号断层是一个小型的断裂系 ,由 5～ 7个北倾断层组成 ,平面上亦向西散开 ;剖面上该断裂系主要反映为向上分开、向下汇聚的帚状断裂系 ;同时还发现了由 3号断裂系控制的断块群。对德南断裂系的精细识别为进一步的钻井勘探和储层建模的研究提供了可靠的依据     

中国步入经济全球化的空间态势与顺应决策取偿问题探讨

适应中国21世纪持续实行全方位经济开放的需要，将中国作为经济全球化空间结构巨系统中的一个重要组成单元，按世界各经济体之间的相互联系、相互作用的研究视角，对中国步入全球化进程中不断推进国内外商品、资本、技术、信息等国际经济要素加速转移的空间演化态势的特殊内涵，着重从其空间跨越性、空间汇剑性、空间依存性等三个主要方面加以揭示与评价，并对中国的相关适应决策取偿问题进行了初步探讨。     

商圈惠顾行为的空间衰减：幂律模式还是指数模式

以上海市商业中心为例,基于匿名手机信令数据,运用引力模型对商圈惠顾行为的衰减模式及其系数进行了验证与对比。结果表明,① 对于商圈惠顾行为,最常用的2种距离衰减函数均具有较高的拟合优度,幂律函数稍优于指数函数;② 总体来看,距离仍是影响城市居民商圈惠顾行为的关键因素,距离衰减效应呈现出随商业中心等级增大而减弱的梯度特征,幂律型衰减系数取值1~3不等,采用既定系数1或2会过高/低估计商圈辐射能力;③ 不可忽视闲暇时间对商圈惠顾行为的约束作用,与周末相比,工作日的距离衰减系数较大,且商业中心等级越低,商圈惠顾行为的衰减性越显著。     

Resident Willingness to Pay for Ecotourism Resources and Associated Factors in Sanjiangyuan National Park,China

Willingness to Pay (WTP), Willingness to Work (WTW) and Willingness to Accept Compensation (WTA) are the three quantitative criteria for assessing local ecological asset values for the social aspects of ecosystem services and residents’ willingness to contribute to and receive compensation for tourism ecology. The objectives of this study are to estimate the residents’ willingness to pay, work and accept compensation for conservation at Sanjiangyuan National Park, and to analyze the relationship between residents’ attitude towards tourism ecology and the ecological assets of the National Park based on a standard questionnaire survey. The dichotomous choice Contingent Valuation Method (CVM) was employed to determine the willingness. The survey conducted in 2018 collected WTP, WTW, WTA, socio-demFographical information, social trust and resident perceptions toward tourism impacts and relevant management strategies from 244 residents in two counties. Based on generalized linear modeling, income and education level are important for residents’ WTP and WTA, but other social characteristics, such as gender and age, do not have significant effects. The social trust is found to be a significant factor on residents’ willingness, despite the limitation on education level. Also, government funding is associated with residents’ inclination to WTP, WTW and WTA, but the support levels differ among the two counties due to geographical and social heterogeneities. The estimated WTP, WTW and WTA for the Sanjiangyuan National Park in 2018 were 1.2448×10 ⁷ yuan, 1.247×10 ⁶ hours and 2.3232×10 ⁷ yuan yr ^-1 based on the survey and published demographics. This study, for the first time, estimates the WTP, WTW and WTA for the Sanjiangyuan National Park and informs ecological conservation managers and policy makers. Ultimately, to maintain the long-term benefits arising from sustainable development, compensation should be specifically tailored and site-dependent, and development measures based on local resources should be adopted by governments to actively support eco-tourism activities.     

基于电力载波通信的自动抄表地理信息系统

基于电力载波通信实现社区集抄网络的物理通信链路的建立,采用了GIS平台实现对对电力载波通信网络的数据采集与存储管理,建立了远程操控平台和互联网络数据发布平台。