A robust method for measuring the Hubble parameter     

M.A. Hendry  S. Rauzy  S.P. Goodwin  J. Gribbin 《Monthly notices of the Royal Astronomical Society》2001,324(3):717-724

We obtain a robust, non-parametric, estimate of the Hubble constant from the linear diameters and rotation velocities of galaxies in the recent KLUN sample, calibrated using Cepheid distances to Hubble Space Telescope Key Project galaxies. There are two key features that make our analysis considerably more robust than previous work. First, the method is independent of the spatial distribution of galaxies and is insensitive to Malmquist bias. It may, therefore, be applied to more distant samples than so-called 'plateau' methods – making it much less vulnerable to the impact of peculiar motions in the Local Supercluster. Secondly, we include information on the galaxy rotation velocities in a fully non-parametric manner: unlike the conventional Tully–Fisher relation we reconstruct a robust estimate of the cumulative distribution function of galaxy diameter at given rotation velocity, without requiring the assumption of, for example, a linear Tully–Fisher relation with symmetric Gaussian residuals.
Using this robust method we find H ₀=65±6 km s⁻¹ Mpc⁻¹ from our analysis – in excellent agreement with many recent determinations of the Hubble parameter, although somewhat larger than previous results using galaxy diameters.  相似文献   

Mapping Paleo‐Fire Boundaries from Binary Point Data: Comparing Interpolation Methods     

Amy Hessl  Jennifer Miller  James Kernan  David Keenum  Don McKenzie 《The Professional geographer》2007,59(1):87-104

Fire history studies have traditionally emphasized temporal rather than spatial properties of paleo‐fire regimes. In this study we compare four methods of mapping paleo‐fires in central Washington from binary point data: indicator kriging, inverse distance weighting, Thiessen polygons, and an expert approach. We evaluate the results of each mapping method using a test (validation) dataset and receiver operating characteristic plots. Interpolation methods perform well, but results vary with fire size and spatial pattern of points. Though all methods involve some subjectivity, automated interpolation methods perform well, are replicable, and can be applied across varying landscapes.  相似文献   

模糊理论在遥感图像分类中的应用   总被引：1，自引：0，他引：1  

王荣华  干嘉元  过仲阳  吴佳勤 《上海国土资源》2007,(4):52-55

利用2000年假彩色遥感图像,采用模糊C-均值法中的欧氏距离和马氏距离法对崇明东滩的遥感图像进行了处理。通过对白色覆盖物、未耕种土地、一号水稻田、水体和二号水稻田的分类结果表明,欧氏距离的聚类结果优于马氏距离。  相似文献   

北京顺义地裂缝带的活动特征及减灾措施   总被引：1，自引：1，他引：1  

任俊杰  张世民  唐荣余 《城市地质》2007,2(1):33-38

本文详细调查了北京顺义地裂缝带的展布和成灾特征,实测了地裂缝灾害最为严重的橡胶二厂内地裂缝的位置和建筑物破坏范围,并综合已有关于顺义地裂缝成因的研究,认为顺义地裂缝带的防治应以控制地下水的开采为根本措施。基于地裂缝的发育程度及成灾特点,在不考虑构造因素的前提下,提出了橡胶二厂建筑用地规划中安全距离的避让方案,即以主破裂带为中心基准线,西北侧建筑安全距离为12m,东南侧建筑安全距离为16m。  相似文献   

对老柞山金矿几点新的认识及找矿靶区预测   总被引：1，自引：0，他引：1  

董本坤  王景德 《吉林地质》2007,26(4):25-28

本文通过对老柞山金矿床地质特征的研究,探讨了矿床不同的成因类型,提出了成矿模式深度、矿体氧化分层和新的成矿类型,对中矿带深部、东矿带东部段和中部段、六道湾段进行了4个区段的成矿预测。  相似文献   

长江三角洲地区地热资源前景与勘查方向探讨     

华建伟  赵剑畏  李菊 《江苏地质》2007,31(3):187-191

长江三角洲地区地热资源前景广阔。"三类"地热资源利用时,可取"因地制宜"、"两条腿走路,异常区先行"的方针。江苏中南部地热资源所处有利的地质构造部位有5类,文中三处可供规模开发的勘查靶区,对上海和浙北地区地热勘查方向提出了讨论意见。  相似文献   

浅议地质录井技术在煤田地质勘探中的运用     

王高科 《中国煤田地质》2007,19(5):72-73,81

地质录井作为石油地质的一项必需技术已为地质界所公认,在石油钻探中,录井技术可以较准确地判定油砂层的位置,将地质录井技术运用到煤田、水文钻探中,可以在取心失败或者无心钻进中有效判定目的层层位。地质录井资料,也是测井解释的重要依据。  相似文献   

初论中亚黑色岩系型金矿床的基本特征——兼论新疆黑色岩系型金矿找矿方向   总被引：2，自引：0，他引：2  

刘春涌  王永江 《新疆地质》2007,25(1):34-39

黑色岩系型金矿床实质上是一种早期形成于富含碳质细碎屑岩建造的滨浅海还原环境,后期经强烈区域低温强动力挤压作用改造形成于韧性剪切带中的低温变质热液金矿床,属韧剪型金矿的1个亚型.在20世纪80年代后引起重视,在世界各地,特别是中亚地区和我国新疆及西南地区取得许多重大找矿突破.中亚地区黑色岩型金矿床十分发育,形成了以穆龙套、库姆托尔、巴克尔奇克为代表的诸多特大型、超大型和大型金矿床.这类矿床具低温蚀变、韧剪性显著、富含碳质和含金石英脉等特点.新疆黑色岩系型金矿成矿地质背景和成矿地质构造条件优越,找矿前景广阔.主要成矿时代为前二叠纪,其次是二叠—三叠纪(昆仑),找矿有利成矿区带主要是北准噶尔、中天山、南天山、东昆仑和北天山,其次有阿尔泰和东准噶尔等地.  相似文献   

Assessing pollutions of soil and plant by municipal waste dump   总被引：1，自引：0，他引：1  

Changli Liu  Yun Zhang  Feng’e Zhang  Sheng Zhang  Miying Yin  Hao Ye  Hongbing Hou  Hua Dong  Ming Zhang  Jianmei Jiang  Lixin Pei 《Environmental Geology》2007,52(4):641-651

Research is few in the literature regarding the investigation and assessment of pollutions of soil and plant by municipal waste dumps. Based upon previous work in seven waste dumping sites (nonsanitary landfills) in Beijing, Shanghai and Shijiazhuang, this study expounds the investigation and assessment method and report major pollutants. Using relative background values, this study assesses soil pollution degree in the seven dumping sites. Preliminary conclusions are: (1) pollution degrees are moderate or heavy; (2) pollution distance by domestic waste that is dumped on a plane ground is 85 m; (3) the horizontal transport distance of pollutants might be up to 120 m if waste leachates are directly connected with water in saturated soils; (4) vertical transport depth is about 3 m in unsaturated silty clayey soils. Furthermore, using relative background values and hygiene standards of food and vegetable this study assesses the pollutions of different parts of reed, sorghum, watermelon and sweet-melon. It is found: (1) in comparison with the relative background values in a large distance to the waste dumping sites, domestic wastes have polluted the roots and stems of reed and sorghum, whereas fine coal ash has polluted the leaves, rattans and fruits of watermelon and sweet-melon; (2) domestic wastes and fine coal ash have heavily polluted the edible parts of sorghum, water melon and sweet-melon. As, Hg, Pb and F have far exceeded standard values, e.g., Hg has exceeded the standard value by up to 650–1,700 times and Cd by 120–275 times, and the comprehensive pollution index is up to 192.9–369.7; (3) the polluted sorghum, watermelon and sweet-melon are inedible.  相似文献   

爆破振动参数在地质灾害鉴定中的运用     

黄作明 《贵州地质》2007,24(4):306-309

本文论述爆破振动参数在地质灾害鉴定中的运用。指出在作爆破振动地质灾害鉴定时,除对建筑物的设计、建筑材料、建筑史、用途、结构、内外环境、地基基础、变形特征进行详细的了解记录外,还必须了解其爆破源点与被鉴定对象之间的地质环境,确定其与地形地质条件有关的系数K,衰减指数α,鉴定对象的最大振幅对应的频率、速度、爆破点的位置及炸药用量,计算振动的安全距离与剖面图上两者之间距离进行比较,为鉴定提出合理的证据。  相似文献