改进的多视PolSAR非局部均值滤波算法

像素点间相似性度量是非局部均值滤波算法的关键所在。从信息论角度出发,提出了一种改进的多视Pol SAR非局部均值滤波方法。该算法在综合分析各类矩阵测度基础上,选定Kullback-Leibler距离作为最优相似度量,结合多视极化相干矩阵服从复Wishart分布,给出了极化相干矩阵的KL距离,并在预处理中应用了极化旋转。实验结果表明,改进方法能够在保持边缘细节的同时有效抑制相干斑。     

自适应非局部均值地震随机噪声压制(英文)

非局部均值滤波是一种基于图像信息冗余的去噪方法,其认为图像自身的有效结构具有一定的重复性,而随机噪声则不具备这一特点,通过利用图像本身的自相似性来达到压制随机噪声的目的,是一种全局的去噪方法。本文把这一思想引入地震数据随机噪声压制中,针对传统非局部均值滤波计算量过大的问题,文章采用分块非局部均值的方式来减少计算量;针对滤波参数选取会影响非局部均值滤波效果的问题,提出一种简单的自适应滤波参数地震数据分块非局部均值算法。模型和实际数据处理结果表明:相对于传统的去噪算法(如f-x反褶积),该方法在压制随机噪声的同时对有效信号保护地更好,具有更高的保真度,更有利于后续的处理和解释工作。     

Marketing the Chinese Dream Home: Gated Communities and Representations of the Good Life in (Post-)Socialist Shanghai

This paper examines the advertising themes and rhetoric that have been assembled in the place-marketing of Shanghai's newly built gated communities. We demonstrate how place-marketing strategies, in this case selling the Chinese dream home, draws upon specific landscape meanings and values that are embedded in Chinese/Shanghainese history, even as symbolic and cultural capital from the contemporary scene also exert their influences. Collectively, these representations of the good life both reflect and reinforce the exclusivist housing aspirations and privatist visions of middle-class residents of gated communities in contemporary Shanghai. While advertisements do not always achieve the outcomes that property developers wish for, there is no doubt that they play significant roles in both shaping and reflecting landscape meanings and values. As medium and outcome, they reveal the growing aspirations of a new Chinese middle class.     

Imagining the Dirty Green City

ABSTRACT

The green city is being elevated to the status of a self-evident good in the theory and practice of urban sustainability. A large literature documents the linked environmental, economic and well-being benefits associated with vegetating urban systems to maximise the ecosystem function. Contemporary urban greening seeks to challenge attempts to expel nature from the city in a quest for order and control. However, by imagining nature as a new mode of urban purification, much effort in the name of the green city inverts and reproduces dualistic understandings of natural and built space. In response, we disrupt the normative dialectics of purity and dirt that sustain this dualism to expose the untidy but fertile ground of the green city. We draw together Ash Amin’s four registers of the Good City – relatedness, rights, repair and re-enchantment – with the artworks of the Australian visual ecologist Aviva Reed. Our work seeks to enrich the practice of more-than-human urbanism through ‘dirt thinking’ by imagining the transformative possibilities in, of and for the dirty green city.     

Towards good governance of urban greening: insights from four initiatives in Melbourne,Australia

ABSTRACT

Urban greening can enhance sustainability and liveability, through conserving biodiversity, mitigating urban heat and enhancing people’s health and wellbeing. However, urban greening is complex, as it occurs in unique ecological settings, with social, cultural and economic factors shaping the forms it takes. This raises questions about the governance of urban greening, including what counts as ‘good governance’. In this paper, we first outline principles of good governance drawn from the natural resource management context. We then present four urban greening initiatives from Melbourne Australia representing different scales, land tenures and organising structures. Following this, we analyse how governance of the four initiatives addresses good governance principles. Our analysis shows that there are diverse ways in which urban greening can be practiced and governed. The importance of more ‘informal’ initiatives should not be discounted relative to formalised initiatives, as a spectrum of approaches can be seen as strength. Further, in determining what constitutes good governance, the standards against which initiatives are assessed should be tailored to their specific circumstances, and consider impacts to the environment itself. These findings point to good urban greening governance being both situated and principled.     

2014年夏初南疆一次持续性强降雨过程的水汽和动力条件分析

全球变暖背景下,极端降水事件频次增多强度增大,对年降水量变化影响显著。2014年6月17~24日,塔里木盆地出现了持续性强降水过程.利用观测资料和NCEP/NCAR逐日6 h再分析资料,对强降水过程的水汽和动力条件进行了诊断分析。结果表明,此次强降水过程,垂直上升运动剧烈区域及水汽辐合区域与大降水的落区近乎吻合。中低空偏东急流加强了气旋的发展,增强了上升运动,且急流的大小决定了塔里木盆地大降水的强度,急流西伸的位置决定了降水的区域。中低空偏东急流轴末端的左侧,对应着大降水的发生区域。主要水汽源地为中亚地区、阿拉伯海和孟加拉湾,其中孟加拉湾和阿拉伯海的水汽通过季风环流输送至青藏高原,再通过高空平流和中低空回流的方式输送至塔里木盆地。     

Assessing participatory GIS for community-based natural resource management: claiming community forests in Cameroon

This paper critically reviews and analyses participatory GIS (PGIS) and participatory mapping applications within participatory spatial planning for community-based natural resource management in developing countries. There is an often implicit assumption that PGIS use is effective, in that it meets content needs, satisfies underlying local stakeholder interests and therefore is a tool for better governance. The analytical framework looks at participatory spatial planning performance with respect to key dimensions of governance, especially the intensity of community participation and empowerment, equity within communities and between 'governed' and 'governing', respect for indigenous knowledge, rights, ownership, legitimacy, and effectiveness. Specific development focus is given by a case study using participatory mapping and PGIS in community forest legitimization, planning and management in Tinto, Cameroon. 'Good governance' criteria are applied ex-post to the implementation procedures, the geo-information outputs, and the longer-term outcomes of the PGIS processes. Impacts of incorporating PGIS were examined in terms of the types and degrees of participation in the process; access to, and the uses made of, the geographic information; whether the information outputs met stakeholders' requirements; and the overall changes in equity and empowerment in the community. It was found that PGIS/participatory mapping processes contributed – positively, though not comprehensively – to good governance, by improving dialogue, redistributing resource access and control rights – though not always equitably – legitimizing and using local knowledge, exposing local stakeholders to geospatial analysis, and creating some actor empowerment through training. PGIS promoted empowerment by supporting community members' participation in decision-making and actions, and by enabling land use planning decisions beyond community forestry itself.     

Accounting for Extensive Secondary Information to Improve Watertable Mapping

Generally, multiple variables are sampled in addition to the one used to quantify the main phenomenon under study. In some situations, this secondary information is sampled exhaustively for the study area and can be incorporated for helping in estimating the variable of interest. There are several methodologies available for incorporating densely sampled secondary information. Collocated cokriging is one of these methodologies and has the advantage to other methodologies, of accounting for spatial correlation. However, one drawback in its application comes from the difficulty in modeling the coregionalization. Simplified models of coregionalization were developed specifically for the collocated cokriging case. This paper presents, through a case study, the incorporation of dense secondary information using collocated cokriging. The watertable above a coal underground mine is mapped using water-level readings at monitoring piezometers complemented by highly correlated topographic data. The incorporation of dense secondary information through the utilization of a linear model of coregionalization and Markov models is comparatively evaluated in various aspects such as mathematical quality, coherence with the natural phenomena and the ease of utilization and modeling. Simple kriging with local varying means also is evaluated as it accounts for nonstationarity and is easily implemented. All these methods that incorporate topography as secondary information for mapping the watertable provided maps more in accordance with the natural phenomena than ordinary kriging using the principal attribute solely. Among these methods, strictly collocated cokriging using a linear model of coregionalization showed overall superior performance.     

煤田构造研究——思路与方法

中国含煤岩系赋存状况的显著特点,是后期构造变形及其变形的时空差异性,造成这种特殊煤田地质条件的控制因素主要包括地球动力学环境、构造演化进程、深部构造与基底属性、构造应力场作用、煤系和上覆下伏岩性组合等五个方面。针对我国煤田构造的发育特点,提出了煤田构造研究的思路,总结了适用于煤田构造研究的技术手段及其主要用途。     

神府矿区柠条塔井田（南翼）水文地质条件及开采方法研究

针对神府矿区柠条塔井田（南翼）含水层的富水性、补径排条件、充水因素、矿井涌水量等水文地质条件，对柠条塔井田（南翼）煤炭开采的影响进行了分析研究，综合该区煤矿床各地段的水文地质条件，提出了留设一定的防水煤柱、预先疏排水、排供结合等各有所侧重的技术途径与开采方法。