GENEALOGIES OF THE GRID: REVISITING STANISLAWSKI'S SEARCH FOR THE ORIGIN OF THE GRID–PATTERN TOWN*

ABSTRACT. As a spatial form, the grid pattern has influenced a range of human activities, from urban planning, architecture, and modern art to graphic design, archaeology, and cartography. Scholars from different disciplines have generally explored the role of the grid within their respective fields of inquiry. One of the earliest geographical attempts to systematically trace the origin and diffusion of the grid‐pattern town was provided by Dan Stanislawski in the mid–twentieth century. In this article I critically examine the limitations of Stanislawski's theory of the grid's origin as a means of challenging the doctrine of diffusionism more generally. I then provide a selective overview of recent approaches to understanding the grid and call for a comparative genealogy of gridded spaces and places.     

求算界限温度日期的一种新方法──样条函数插值法

本文根据某站点各月平均气温,通过计算机,用样条函数插值法模拟年温变化曲线,进而直接求算出主要界限温度初终日期、间隔日数及其相应积温,并与用滑动平均法得出的结果进行了比较检验。     

基于栅格数据的流域降雨径流模型

本文在研究降雨时空分布不均匀与下垫面自然地理参数空间分布不均匀，对降雨径流过程影响的基础上，提出了一种在地理信息系统支持下的动态分布式降雨径流流域模型，实现了基于栅格的坡面产汇流与河道汇流的数值模拟，能够获得流域上任意模拟时刻任意栅格的径流量。模型视栅格为水文一致性单元，水文参数在栅格内一致，在相邻栅格间变化，采用Ｈｏｌｔａｎ模型计算下渗率，水量平衡方程和线性水库的马斯京根法进行栅格产汇流演算，模     

MYTHOLOGIES OF THE GRID IN THE EMPIRE CITY, 1811–2011*

In this article, I examine the performative dimensions of historical narration as a form of modern mythmaking by reconsidering conventional narratives on the “origins” of Manhattan's grid street plan of 1811. The historical mythology of the grid espoused in canonical readings of the Plan of 1811 relies extensively on a rearticulation of the official explanation that the grid's designers provided in a foundational text known as the “Commissioners’ Remarks”. I argue that such accounts result in an extraordinarily narrow and formulaic interpretation of the utilitarian motives and intentions behind the city's grid plan, one that reinforces a form of “morphological essentialism”. To support this argument, I shift the focus of attention beyond the “Commissioners’ Remarks” in order to complicate readings of the intentionality that gave rise to the 1811 street plan. I conclude by suggesting that the mythic search for the “origins” of the grid in the realm of founding intentions can most effectively be challenged by drawing attention to the proliferation of countermyths of gridded space.     

COMPARING TRADITIONAL METHODS FOR SELECTING CLASS INTERVALS ON CHOROPLETH MAPS*

The most common goal when classing data for choropleth maps is to create homogeneous classes which contain similar data values. None of the four traditional data classing methods examined here (quartile, equal interval, standard deviation, and natural breaks) consistently generalized the experimental data sets into homogeneous classes. These methods were most accurate for data sets with specific distributional characteristics, but none classed all of any type of distribution accurately. Only the optimization method produced reliable and accurate results for all of the experimental data.     

TWO METHODS FOR INVESTIGATING THE GEOGRAPHIC DISTRIBUTION OF DIURNAL PRECIPITATION PATTERNS *

Two alternative approaches for the depiction of the geographic distribution of diurnal precipitation patterns are presented. The standard deviation method results in a plot of significant peak precipitation hours for several locations along a transect. The correlation fields approach allows researchers to visualize geographic patterns significantly associated with a given diurnal precipitation distribution. These techniques may be applied to reveal changes in diurnal patterns over both space and time.     

Generating Surface Models of Population Using Dasymetric Mapping*

Aggregated demographic datasets are associated with analytical and cartographic problems due to the arbitrary nature of areal unit partitioning. This article describes a methodology for generating a surface‐based representation of population that mitigates these problems. This methodology uses dasymetric mapping and incorporates areal weighting and empirical sampling techniques to assess the relationship between categorical ancillary data and population distribution. As a demonstration, a 100‐meter‐resolution population surface is generated from U.S. Census block group data for the southeast Pennsylvania region. Remote‐sensing‐derived urban land‐cover data serve as ancillary data in the dasymetric mapping.     

SAMPLING REMOTELY SENSED IMAGERY FOR STORAGE,RETRIEVAL, AND RECONSTRUCTION*

A major difficulty in remote sensing is handling the many data from sensors aboard aircraft and satellites. In this paper we identify an optimal procedure for sampling remotely sensed data before their storage or on their retrieval. The procedure depends on spatial correlation in the scene and uses kriging to estimate values that have been lost. An example in which data from an airborne multispectral scanner could be diminished to only about one tenth without serious loss of precision illustrates the method.     

复杂地形条件下风速插值研究——以吉林省为例

以ARCGIS为平台,利用吉林省1∶25万DEM数据,土地利用数据和气象台站资料,在Kriging插值的基础上,综合考虑下垫面、海拔高度、坡度、坡向和坡位等地形要素对风速的影响,对吉林省的冬季风风速分布进行模拟。研究结果表明,基于地形因子的风速校正有效提高了风速插值的精度,可以作为风速插值方法的有效补充,实现复杂地形条件下风速的精确模拟。     

基于GIS的新疆气温数据栅格化方法研究

以新疆99个气象台站1971-2010年年平均气温为数据源,采用多元回归结合空间插值的方法对新疆区域气温数据进行栅格化研究。建立了年平均气温与台站经纬度和海拔高度的多元回归模型,对于残差数据的插值采用了反距离权重法(IDW) 、普通克立格法 (Kriging)和样条函数法(Spline)3种目前应用广泛的空间插值方法,针对于这3种方法进行了基于MAE和RMSIE的交叉验证和对比分析,结果表明在新疆的年平均气温的GIS插值方案中,IDW方法精度总体要高于其他两种插值方法。     

SHORT COMMUNICATION CLASSIFICATION METHODS FOR MULTIVARIATE QUALITY PARAMETERS

There are many chemical products where product conformity is decided upon by qualitative humanjudgements of overall product quality.Nowadays,quantitative instrumentally determined qualityparameters become available which are intended to replace such qualitative judgements by means ofautomatic decision rules using multivariate specification limits.Six classification methods to derive suchlimits are compared in terms of their power to predict corresponding human judgements on overall colorconformity of 17 dyestuffs based on historical quality data.Standard statistical classification methodsturned out to be unacceptable for the routine generation of decision rules because of the frequent distinctsuboptimality of their predictive power.Instead,a simple non-statistical classification method utilizinga priori knowledge about the underlying data structure yielded uniformly satisfactory decision rules.     

CHANGES IN U.S. NATIONAL MOBILITY LEVELS*

This paper investigates the decline in the national mobility level that occurred during 1970-1983. The effects of generation size are discussed in detail; bigger generations may move at lower rates because of the increased competition for jobs and housing. The changing age composition of the population will imply further mobility declines during coming decades if age-specific mobility rates remain constant. A consideration of anticipated changes in the size of the young adult cohort suggests that the national mobility rate may increase slightly over the next decade, before beginning a relatively modest decline during 1995-2040.     

云南逐月雨量和气温的格点数据资料场建立

根据云南各气象台站的逐月雨量和气温观测数据资料,采用距离平方加权平均的格点插值方法,建立了云南(98.0°E～106.0°E、21.0°N～29.0°N)1951年1月～2002年12月0.25°×0.25°经纬度分辨率的逐月格点降水和气温数据资料场。应用该格点数据资料场,分析得到了云南年降水量场和年气温场变化的一些基本空间分布特征和时间演变特征。     

人口统计数据的空间转换

在经济和社会研究中,所要研究的区域之上经常没有数据,而这些数据需要由已知区域的数据求得,即统计数据需要空间转换,这就通常涉及到面积内插。本文从GIS的角度研究如何解决人口内插问题,认为面积内插和GIS中的叠加分析是一致的。在传统的面积内插方法的基础上是提出了基于人口真实分布的面积内插方法,并推导出了公式。同时提出了人口密度的递归算法,即把居住区分为人口稀疏地区和人口稠密地区,估计出人口稀疏地区的人口密度,就可以求出人口密集地区的人口密度;再把人口密集区分为新的人口稀疏区和密集区,此过程反复直至求出接近于人口真实分布的人口模型。     

陨石Cr同位素组成测试技术及其在天体化学研究中的应用

Cr同位素作为一个新的研究手段,在天体化学领域中主要应用于追溯太阳系早期历史演化和定年.Cr同位素组成测定的主要技术是二次离子探针、热电离质谱和多接收等离子质谱,本文对这些分析技术的特点和发展作了论述.随着分析技术的发展,目前对ε(53Cr)和ε(54Cr)测定精度分别达到6 ppm和12 ppm(2σ).高精度Cr同...     

基于温度梯度修正的山东省年均温资料插值方法比较研究

对研究区气象站点的年均温与其他地理要素进行相关分析,发现温度与高程具有较高的相关系数。在此基础上,设计了使用空间内插方法分别获得研究区气温与高程,再根据内插得到的高程与实际DEM之差对内插得到的气温进行温度梯度修正,以得到实地气温的方法。这种方法可以有效的消除对气温进行内插时,高程要素对其产生的干扰。分别运用IDW、Kriging、Spline3种方法进行插值,比较结果发现IDW法得到的结果最能反映温度随空间位置变化的趋势,较其他两种内插方法具有较大的优势。     

Surface modeling of DEMs based on a sequential adjustment method

A sequential adjustment (SA) method is employed to decrease the computational cost of high-accuracy surface modeling (HASM), and the SA of HASM (HASM-SA) is being developed. A mathematical surface was used to comparatively analyze the computing speed of SA and the classical iterative solvers provided by MATLAB 7.7 for solving the system of linear equations of HASM. Results indicate that SA is much faster than the classical iterative solvers. The computing time of HASM-SA is determined by not only the total number of grid cells but also the number of sampling points in the computational domain. A real-world example of surface modeling of digital elevation models (DEMs) with various resolutions shows that HASM-SA is averagely more accurate and much faster than the commonly used interpolation methods, such as inverse distance weighting (IDW), kriging, and three versions of spline, namely regularized spline (RSpline), thin-plate spline (TPS), and ANUDEM in terms of root mean square error (RMSE), mean absolute error (MAE), and mean error (ME). In particular, the ME of HASM-SA at different spatial resolutions is averagely smaller than those of IDW, kriging, RSpline, TPS, and ANUDEM by 85%, 83%, 83%, 53%, and 19%, respectively. The high speed and high accuracy of HASM-SA can be due to the absence of matrix inversion computation, combined with the perfect fundamental theorem of HASM.     

一种基于超曲面样条函数的三维空间插值方法

将二维曲面样条函数插值法进一步引申,提出一种基于超曲面样条函数进行三维空间插值的新方法,介绍超曲面样条函数的构造方法,给出利用该方法进行三维空间插值的数值实现过程。最后以插值形成三维空间规则数据场为例,证明利用超曲面样条函数法进行三维空间插值的可行性和准确性。     

环境制图中数量特征的表示方法研究

对环境制图中反映数量特征的定点符号法,包括几种连续和分级比率符号、非比率分级符号以及相关内容数量特征的表示进行了具体分析比较.对表示要素数量特征面状分布的网格法和等值线法,也结合实例进行了评述.