BOOK REVIEWS

Books reviewed in this article: Boundary Control and Legal Priniciples . Curtis M. Brown , Walter G. Robillard and Donald A. Wilson . Lost Initiatives: Canada's Forest Industries, Forest Policy, and Forest Conservation . R. Peter Gillis and Thomas R. Roach . The Navajo Atlas: Resources, People, and History of the Dine Bikeyah . James M. Goodman . The City and the Sign . M. Gottdiener AND Alexandros Ph . Lagopoulos , EDS. The Comfortable House: North American Suburban Architecture 1890–1930 . Alan Gowans . Arabic-Islamic Cities. Building and Planning Principles . Besim Salim Hakim . Contemporary Climatology . Ann Henderson -Sellers and Peter J. Robinson . A Trace of Desert Waters . Samuel G. Houghton . Geography, Resources and Environment. Vol. 1: Selected Writings of Gilbert F. White. Vol. 2: Themes from the Work of Gilbert F. White . Robert W. Kates AND Ian Burton , ED. Spatial Dimensions of Unemployment and Underemployment (A Case Study of Rural Punjab) . Gopal Krishan . Maps of the Holy Land: Cartobibliography of Printed Maps, 1475–1900 . Compiled by Eran Laor , assisted by Shoshana Klein . The Geography of Third World Cities . Stella Lowder . A Perspective on U.S. Farm Problems and Agricultural Policy . Lance Mc Kinzie , Timothy G. Baker AND Wallace E. Tyner . Soil Erosion and Its Control. R.P.C . Morgan , ED Geopolitics . Patrick O'Sullivan . Landscape, Meanings and Values . Edmund C. Penning -Rowsell AND David Lowenthal , EDS.     

A SIMILARITY MEASURE FOR CHEMICAL DATA: APPLICATIONS TO CLUSTER ANALYSIS

The results of unsupervised pattern recognition methods are critically dependent on the measure ofsimilarity used for clustering objects. There is little a priori information available on the relative utilityof various similarity measures. We introduce here an alternative similarity measure based on the metrictensor measure (MTM). Two standard clustering strategies are tested with the proposed similaritymeasure: hierarchical clustering and the K-median method. As data we use the ARCH obsidian data,a data set on Hungarian coal, and trace element data on Hungarian paprika. Differences from theMahalanobis distance measure are described for intraclass relations.     

对正热电离质谱法硼同位素测定的实验设计和条件优化

为了确定正热电离质谱法测定硼同位素时的最佳实验条件 ,采用均匀设计法进行实验表头设计 ,并用MATLAB进行数据处理和回归模型优化。将最佳优化条件应用于硼同位素测定中 ,得到了与理论计算相吻合的高精度测定结果。     

Quantifying septic nitrogen loadings to receiving waters: Waquoit Bay,Massachusetts

Abstract

Waquoit Bay, a shallow bay on Cape Cod, Massachusetts, is exhibiting symptoms of eutrophication, largely attributed to septic nitrogen inputs. This study assessed septic nitrogen inputs by linking a three-dimensional ground-water model, a geographic information system (GIS), and a customized spatio-temporal nitrogen loading program. Owing to the slow speed of ground-water movement, the bulk of septic nitrogen entering the bay lags behind development by nearly a decade. Even if residential development is held at 1989 levels, nitrogen input from septic systems wilt increase by 36% over the current levels. At full residential build-out (i.e., development), septic nitrogen loading will eventually increase to more than twice the current levels.     

基于复杂性测度的中国洪灾受灾面积变化研究

采用复杂性测度方法来进行中国洪涝灾害受灾面积变化的研究。结果表明:(1) 20世纪80、90年代中国洪灾受灾面积及其复杂度均持续上升,说明洪灾剧烈,而且复杂多变、不确定性增加;进入21世纪,两者趋缓或下降,即中国洪涝灾害有所缓解;(2) 从分省区的结果来看,洪灾受灾面积的未来趋势具有区域特征,主要可划分为两个加剧的区域和两个减缓的区域;全国各省市区依据受灾面积趋势可划分为4个等级,在此基础上给出中国的未来洪灾受灾面积趋势图。     

制冷控制系统研制与探析

根据实际应用研制制冷控制系统,该系统采用温度测量、PID控制及PWM脉宽调制等技术实现了对目标对象的制冷处理,具有一定的应用价值。     

ELIMINATING COMPLEX EIGENVECTORS AND EIGENVALUES IN MULTIWAY ANALYSES USING THE DIRECT TRILINEAR DECOMPOSITION METHOD

The direct trilinear decomposition method(DTDM)is an algorithm for performing quantitative curveresolution of three-dimensional data that follow the so-called trilinear model,e.g.chromatography-spectroscopy or emission-excitation fluorescence.Under certain conditions complexeigenvalues and eigenvectors emerge when the generalized eigenproblem is solved in DTDM.Previouspublications never treated those cases.In this paper we show how similarity transformations can be usedto eliminate the imaginary part of the complex eigenvalues and eigenvectors,thereby increasing theusefulness of DTDM in practical applications.The similarity transformation technique was first used byour laboratory to solve the similar problem in the generalized rank annihilation method(GRAM).Because unique elution profiles and spectra can be derived by using data matrices from three or moresamples simultaneously,DTDM with similarity transformations is more efficient than GRAM in the casewhere there are many samples to be investigated.     

Parsivel~激光降水粒子谱仪及其在气象领域的应用

降水粒子特性是大气运动和云内微物理过程的综合结果,在云降水物理及人工影响天气领域有着重要的意义。传统的测量方法不适合对大量数据分析寻找规律,德国OTT公司的Parsivel激光降水粒子谱测量系统可以较好解决自动测量难题。该仪器是以激光测量为基础的粒子测量传感器,采用平行激光束和光电管阵列结合,当有降水粒子穿越采样空间时,自动记录遮挡物的宽度,通过穿越时间计算降水粒子的尺度和速度,根据各种参数的综合信息对降水粒子进行分类,并能够以数字形式显示瞬时降水强度、降水粒子总数、累积降水量、降水时的能见度和雷达反射因子,以图形方式显示降水粒子尺度谱、速度谱、降水粒子分类且自动生成天气现象代码,实现天气现象的自动识别。激光降水粒子谱仪主要用于气象水文观测。在雷达气象学领域可用于Z/R关系的拟合修正,比传统的用雨量筒观测数据拟合效果好得多;由降水粒子谱仪测量雨滴的降落速度,可以对天气雷达垂直向上测量的粒子径向速度谱进行校正。人工影响天气的效果检验一直是一个难题,自然降水粒子谱分布形式与人工催化以后的降水粒子谱型理论上应当具有较大的差别,人工增雨作业降水滴谱变化物理响应和降水强度时间变化响应都有明显的区别。如果能够实时检测到这些差别,就能够充分说明人工催化的有效性。未来如果能够进行联网观测记录区域性降水、降雹,就有充分证据表明人影作业的有效性,在定量化作业效果评估以及灾害损失评估等方面应用潜力巨大。利用该仪器已经对一年的自然降水过程进行了连续观测,并将所获得的降水粒子谱、雨滴浓度值随时间变化状况与卫星反演的云顶有效粒子半径时间变化趋势进行了对比,发现有较好的一致性。