Market areas – a methodological reflection on their boundaries

According to a classical definition the size of a market area results from the spatial range of the demanded and/or supplied goods and services. Distance-sales-relations or price-sales-relations produce overlapping and interconnecting sales cones with fuzzy limits in space. Thus the problem consists in identifying boundaries or edges of boundaries which result from the intensity of (spatial) spending power flows or spatial consumer shopping behaviour defining a system of functional regions. They can be estimated empirically by surveys or by mathematical models. In the former case the customer flows or spending power flows themselves are empirically recorded, in the latter they are determined from structure data of the supply and demand locations taking the distance barrier into consideration. The methods and their variants are described, their strengths and weaknesses discussed and possible areas of application presented. This revised version was published online in July 2006 with corrections to the Cover Date.     

含油气盆地储层建模和模拟研究评述

概述了国内外储层建模和的研究现状和进展,对储层建模和模拟的主要方法进行了评述,并对我国在该领域中存在的主要总是作解决途径作了探讨,建立了该项研究工作的一航流程。     

The Wilkinson Microwave Anisotropy Probe (WMAP) confirmed the model of our observed relativistic universe

The Wilkinson Microwave Anisotropy Probe (WMAP) confirmed the model of flat expansive homogeneous and isotropic relativistic universe, which describes the properties of our observed flat expansive homogeneous and isotropic relativistic Universe in the first (linear, Newtonian or classical-mechanical) approximation.     

Error bounds in cascading regressions

Cascading regressions is a technique for predicting a value of a dependent variable when no paired measurements exist to perform a standard regression analysis. Biases in coefficients of a cascaded-regression line as well as error variance of points about the line are functions of the correlation coefficient between dependent and independent variables. Although this correlation cannot be computed because of the lack of paired data, bounds can be placed on errors through the required properties of the correlation coefficient. The potential meansquared error of a cascaded-regression prediction can be large, as illustrated through an example using geomorphologic data.     

线性规划在企业管理中的应用

本文是通过对青岛木器一厂的生产经营情况进行分析,综合建立线性规划(简称L.P)数学模型,然后用电子计算机求解,作出利润目标的决策和安排实现利润目标的最优生产计划。还运用解原L.P的对偶问题,求出影子价格和进行灵敏度分析,帮助企业找出生产薄弱环节,并提出内部挖潜的建议。     

不规则波折射的数学模型

本文对光易型方向函数中的集中度参数Ｓｍａｘ进行了推算，得到了在不同底坡和入射角情况下，Ｓｍａｘ～ｄ／（Ｌｓ）。的关系曲线，从而较合理地给出了浅水区域的方向谱Ｓ（ｆ，θ）。本文用谱分量的线性迭加法建立了不规则波折射的数值模式，计算了具有各种理论方向谱的不规则波在平行直线状等深线海滩上的折射。其结果得到了不规则波折射系数ｋｓｒ的计算图。将所得的结果与用正弦波求得的值作了比较。另外，本文还探讨了方向谱的分割数与不规则波折射计算精度的关系，并对如何节省计算机时作了研究，从而确定了频率和方向的最佳分割数。     

南海东北部内潮数值研究

导出二维三层（准三维）潮流与起伏地形相互作用而产生内潮波的非线性数学模型，并分别以Ｍ２分潮、Ｋ１分潮为策动期波，数值求解南海东北部大陆斜坡对策动潮波的响应。结果表明：台湾浅滩南面斜坡对Ｍ２分潮响应最为强烈，东沙群岛东面斜坡次之，其余海域无显著响应；对Ｋ１分潮的响应则以一统暗沙东南面斜坡最甚，其次为东沙群岛东南的斜坡，其余海域响应微弱。     

中国海洋红藻——御前凹顶藻Laurencia Omaezakiana Masuda的形态与结构特征

凹顶藻类是近年来海洋红藻分类学研究的主要热点之一(Garbary et al.，1998；Nam et al.，2000；Nam et al.，2001；Masuda et al.，1996， 1998a，2001)。从经典分类学方面来说，这个类群不仅形态学差异大，而且解剖学特征也存在许多需要进一步探讨的问题，难度较大，所以长期以来其系统并不是十分明确。Saito(1967)提出的凹顶藻两亚属的分类系统应该说在当时是比较先进的。各国的藻类学家对此意见比较一致(张峻甫等1985；McDermid 1988)， 虽然有些修改或补充(张峻甫等1985；Furnari et al.，1993；Gil-Rodrigeuz et al.，1993)，但Nam(1990)对此提出了不同意见，他认为营养性生长轴产生的围轴细胞数目比其他分类特征更稳定，因此建议修改凹顶藻类的系统鉴定特征。Nam等(1994)认为凹顶藻属应该划分成两个属:凹顶藻属和拟凹顶藻属Osmundea Stackhouse。随后，Garbary等(1998)认为新的凹顶藻属应该再划分成两个属:凹顶藻属及软骨凹顶藻属Chondrophycus。目前，早期的凹顶藻属被划分成了3个属：凹顶藻属、软骨凹顶藻属及拟凹顶藻属。作者赞同后者的观点。 长期以来，中国凹顶藻类的研究在海藻分类学中是比较薄弱的一个方面，除了Tseng(1943)、张峻甫等(1980，1985)对香港和西沙群岛有过较详细研究外，其他的都比较简略。而随着国际上凹顶藻研究的不断深入，中国于1998年也开始了中国凹顶藻类的系统研究工作。目前作者发现仅在黄渤海分布着一个凹顶藻新记录种，即御前凹顶藻Laurencia omaezakiana Masuda。根据最新的凹顶藻类分类系统，此种仍然属于凹顶藻属。由于凹顶藻属物种含有丰富的次生代谢物质，因此，作为海藻化学研究的热点物种之一，有必要对其进行详细的介绍。     

Natural and Anthropic Middle-term Variations in the Delta System at the Mouth of the Goro River (Po Delta, Italy)

Abstract. The modern delta system of the Po River is the result of an evolution strictly controlled by anthropic factors and mainly developed during a period of climatic deterioration (Little Ice Age 1550/1850).
At the beginning of the 17^th century the main branch of the Po River, Fornaci Po, was modified with the "Cut of Viro" in order to avoid landfill of the Venetian Lagoon. Simultaneously, the southernmost branch of Ariano, or Goro, was forced to flow southwards. Subsequent sedimentary variations, caused by changes in the climatic conditions, contributed to make the area supplied by the Goro Po River increasingly lagoonary. In the second half of the 19^th century (end of the Little Ice Age – L.I.A. –), the first coastal spits started to take shape and developed in different systems throughout the entire following century. Coastal spits turned out to produce in the original bay, a progressive closure towards the sea. The strong decrease in solid loads, characterising the second half of the 20^th century and mainly due to anthropic factors, marks the beginning of a new phase extending to the overall Po Delta system, in which the mouth layout is controlled by wave energy.