广州市美丽乡村空间分异特征及其影响因素

以广州市已公布的4批美丽乡村建设试点数据为基础，通过最邻近指数、基于Riple’s函数的多距离空间聚类分析、核密度分析和叠置分析等方法，探讨了广州市美丽乡村的发展现状、空间分布格局及其影响因素。结果表明：1）自2013年起，广州市美丽乡村数量逐年递增且增长率呈现上升趋势；2）广州市美丽乡村空间分布呈明显的集聚型分布；3）Ripley’s函数分析表明美丽乡村要素点空间分布格局随距离变化略有不同，在0.14 km处集聚强度达到最大；4）核密度分析显示美丽乡村高密度区域主要分布在广州南部和西北部，包括番禺－南沙1个热点主核心区和从化、花都－白云2个热点副核心区，密度分布呈现多核心不均衡特点；5）乡村的地形水文、人文历史、交通区位和政策规划为美丽乡村空间分布的主要影响因素，其中，政策规划因素对“美丽乡村群”空间格局的形成起决定性影响。空间分布特征总体反映出广州市美丽乡村规划建设初见成效，并逐步形成以热点核心区为基础的“美丽乡村群”。最后，在乡村选点、空间优化、价值提升以及乡村治理等方面提出若干建议。     

NUMERICAL MODELING OF CUMULUS CLOUD CHEMISTRY—PART Ⅰ.MODEL DEVELOPMENT

A one-dimensional cumulus cloud chemistry model(1CCCM)is developed to simulate cloudphysical processes and chemical processes during the evolution of a convective cloud.The cloudphysical submodel includes a detailed microphysical parameterized scheme of 20 processes.Thechemistry submodel is composed of three parts:gas phase chemistry,aqueous phase chemistry andscavenging of soluble gases.The gas phase reaction mechanism contains 85 reactions among 45species including 13 organics.The aqueous phase reaction mechanism contains 54 reactions among40 species and 12 ion equilibria.Mass of 19 gases is transported between the gas phase and theaqueous phase.With this model,studies may be made to analyze the interactions among processesduring lifetime of a cumulus cloud.     

Oort Cloud Comet Perihelion Asymmetries: Galactic Tide, Shower or Observational Bias?

We investigate the distribution of Oort cloud comet perihelia. The data considered includes comets having orbital elements of the two highest quality classes with original energies designated as new or young. Perihelion directions are determined in galactic, ecliptic and geocentric equatorial coordinates. Asymmetries are detected in the scatter and are studied statistically for evidence of adiabatic galactic tidal dynamics, an impulse-induced shower and observational bias. The only bias detected is the well-known deficiency of observations with perihelion distances q > 2.5 AU. There is no significant evidence of a seasonal dependence. Nor is there a substantive hemispherical bias in either ecliptic or equatorial coordinates. There is evidence for a weak stellar shower previously detected by Biermann which accounts for ≈ 10% of the total observations. Both the q bias and the Biermann star track serve to weaken the evidence for a galactic tidal imprint. Nevertheless, statistically significant asymmetries in galactic latitude and longitude of perihelia remain. A latitude asymmetry is produced by a dominant tidal component perpendicular to the galactic disk. The longitude signal implies that ≈ 20% of new comets need an additional dynamical mechanism. Known disk non-uniformities and an hypothetical bound perturber are discussed as potential explanations. We conclude that the detected dynamical signature of the galactic tide is real and is not an artifact of observational bias, impulsive showers or poor data. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of coronal mass ejection on geomagnetic activity during 1988–1993

The most rapid and dramatic evolution in the solar corona occurs in events now known as Coronal Mass Ejections (CMEs). There have considerable importance for our understanding of the evolution of the mass and energy injected into the interplanetary medium. In this work, we have studied the relation of CMEs with geomagnetic activity for the period of 1988 to 1993. Not all CMEs are capable of producing geomagnetic disturbances. Our study indicates that the maximum chance of a geomagnetic disturbance occurs two to three days after a CME in association with B-type solar flares.     

大质量年轻星体新的C18O(1-0)发射

利用紫金山天文台青海观测站13.7米的毫米波望远镜对74个大质量年轻星体或候选进行了C^18O(1-0)的谱线观测。在63个源中观测到了C^18O(1-0)发射，其中57个天体第一次探测到C^18O(1-0)谱线发射。根据谱线辐射温度（TR^*)和半宽（△V），利用LTE方法计算了每个测量源的C^18O(1-0)发射的光学厚度和C^18O(1-0)分子的柱密度。讨论了^13CO(1-0)和C^18O(1-0)的谱线强度比和积分强度比。     

用雷达回波资料识别雹云的最新进展

本文评述了当前国内外利用雷达回波资料识别雹云的现状,着重介绍了笔者近年来利用雷达回波资料建立雹云识别模式的研究工作,并展望了雹云识别的未来发展前景。     

东南极普里兹湾1990年1—2月大风过程与气旋和锋面活动分析

本文用澳大利亚墨尔本气象中心,苏联南极青年站地面天气图和NOAA-10,NOAA-11极轨卫星云图确定了东南极普里兹湾及其附近海域1990年1—2月份气旋中心位置;讨论了这些气旋的活动特征。分析了实测大风对应的天气系统,天气形势和卫星云图特征,指出普里兹湾沿海存在气旋、锋面以及锋面云和气旋先后相继的影响。锋面及锋面、气旋先后相继影响与500hPa上的强高压脊天气形势、强风与锋面带中纹理非常不均匀区域有密切关系。     

地壳相对活动区的灰色划分

本文根据灰色系统中的聚类原理,提出了有关复测网区内地壳活动区的灰色划分方法,即根据动态平差得到的观测值速率和关联度这两个灰类指标,对观测值按不同的灰类进行灰色聚类,从而划分地壳的相对活动区。文中给出了重力网重复观测值的灰色关联度、聚类权以及灰类白化函数的计算方法,并用一个复测重力网资料进行了计算,结果表明:用该方法所划出的相对活动区与实际情况比较符合。     

A multivariate statistical study of copper mineralization in the central section of Mosaboni Mine, Eastern Singhbhum, India

A multivariate statistical analysis was carried out with log-transformed values of Cu, Ni, Co, Pb, Zn, Ag, Cr, Mn, Ca, and Sr in several sets of samples collected across the mineralized base metal zone in sheared soda granite, feldspathic schist, and chlorite schist from the central section of Mosaboni Mine of the famous Singhbhum Copper Belt of eastern India. Linear correlation coefficient matrices of two sets of ore samples (>0.5% Cu)—one from levels 18 and 21 and the other from levels 25 and 28—indicate two well-defined and distinct clusters comprising Cu, Ni, Co, Pb, and Zn on one hand and Ca, Sr, and Mn on the other. Varimax-rotatedR-mode factor analysis of two above-noted sample sets, taken along with available geologic information, indicates that over 80% of the variability in data matrices for 9–10 elements can be accounted for by four distinct processes: (a) an early phase of copper mineralization which apparently replaced Mn, Ca, and Sr in the host rock; (b) a silicate-cum-oxide phase of crystallization/recrystallization of host rock; (c) remobilization of sulfide-forming ore elements (Cu, Ni, Co, Pb, and Zn); and (d) a phase of mineralization of Ag which appears to have replaced Cr, Ca and Cu. Process (c) was quantitatively most important. Factor score studies are suggestive of preferred introduction of Ni, Co, Pb, and Zn along central parts of preexisting copper-mineralized zones.     

集聚型空间点模式结构信息提取研究

空间点模式是一个2维离散点集,点集中的每一个元素代表地球表面一个点状目标的空间位置。当2维离散点集具有集聚特征时,称其为集聚型空间点模式,它与空间聚类、制图综合和空间分析的许多具体应用紧密相关。如何提取集聚型空间点模式的结构信息(集聚子群的个数和对应的集聚中心)是其中尚未彻底解决的问题。作者以几何概率为理论基础,提出测度正方形区域内2维离散点集分布特征的H函数并推导其解析表达式,运用H函数设计和实现了集聚型2维离散点集结构信息提取的通用算法。利用该算法处理一个由居民地坐标数据得到的具有集聚特征的空间点模式,提取出其结构信息并进行可视表达。分别以该空间点模式中的各离散点为顶点和发生元生成Delaunay三角网和Voronoi图,在Delaunay三角网中保留面积最小的前1/10、前1/100三角形的顶点,在Voronoi图中保留面积最小的前1/10、前1/100邻近多边形的发生元,将可视表达的点集结构信息分别与依据Delaunay三角网和Voronoi图得到的结果进行对比分析。结果表明,运用H函数能够有效地提取出集聚型空间点模式的全局性结构信息,而Delaunay三角网和Voronoi图虽然能够反映其局部密度,但在提取全局结构信息时存在局限性。