上海宁波两港空间关系研究

上海港和宁波港是长江三角洲港口体系中两个最重要的港口。基于国内外港口空间关系研究现状的评述和借鉴,本文对两港的空间关系进行长时段考察和定量测度,认为近代以来,上海宁波两港的空间关系大致经历了枢纽港－支线港到枢纽港－大型深水直挂港的转变。今后上海港仍将保持较快增长,而宁波港的发展势头将更加强劲,很有可能和上海港形成双枢纽港模式。     

海南岛戈枕含金剪切带构造应力与物质调查对应关系的初步探讨

通过系统地野外地质调查,取样和分析测试,结合计算机模拟,探讨戈枕含金剪切带物质在构造应力作用下的调整,结果表明剪切构造应力对物质的调整具有一定的对应规律,是金富集成矿的重要因素。     

Mechanics and fluid transport in a degradable discontinuity

This paper briefly examines the mechanical and hydraulic response of discontinuity in a geologic medium that can experience degradation of its contacting regions due to shear and normal stresses acting on it. The paper discusses the methodologies that can be adopted to describe the mechanics and fluid transport behaviour of such a joint. The calibration capabilities of the model are illustrated by appeal to a comparison of experimental results with computational predictions.     

Effect of cryostructures on the uniaxial compressive strength of frozen clay

Unconfined uniaxial compressive tests were performed to study the influence of cryostructure on frozen clay's behavior,such as strain-stress,compressive strength,and failure characteristics,at temperatures varying from-10 to-2°C and strain rates varying from 1.0×10-5to 1.0×10-3s-1.Artificial samples were prepared of three types:(1)integral structure,(2)laminar structure,and(3)reticular structure.The impact of temperature,strain rate,and cryostructure on the mechanical properties is discussed.In general,frozen clay with various cryostructures shows strain-softening behavior in the range of testing temperatures and strain rates.For frozen clay of different cryostructures,the ultimate compressive strength increases with increasing strain rate and decreasing temperature.Under the same testing conditions,the ultimate compressive strengths from high to low are in integral samples,laminar samples,and reticular samples.Failure strain of frozen clay generally increases with increasing temperature and does not indicate any correlation with cryostructure or strain rate.The failure mode of integral and reticular samples was shear failure,while laminar samples showed tensile failure.     

人工神经网络在地震中期预报中的应用

将ＢＰ神经网络用于地震中期预报。使用一些常用的地震学指标作为神经网络的输入,而将ＢＰ神经网络的输出作为表征地震活动增强的特征参数Ｗ１,并将其用于华北地区进行空间扫描。结果表明,中强地震前１～３年未来震中周围通常出现明显的Ｗ１值中期异常区,该方法具有较好的中期预报效果。     

西双版纳不同山地长果桑及食果动物

热带雨林是大自然赋予人类的珍贵资源宝库 ,有着久远的发展历史 ;认识其间的动植物关系以及人类影响下的动态变化 ,不仅有重要学术意义 ,而且对热带山地生态系统的保护、恢复 ,山区的持续发展有现实指导作用。我们在长果桑果期研究了西双版纳不同强度人为影响的热带山林摄食动物种群结构 ,对地区的发展和热带山地生态系统的维护有了新的认识。     

线目标空间冲突自动检测研究现状

由于线要素的特殊性和复杂性,线要素逐步成为空间冲突检测的重点和难点。通过对线目标空间冲突自动检测技术和方法现状的研究,指出了当前研究方法的不足和局限,并以道路空间冲突检测为例,提出了利用基于空间关系思想检测线线空间冲突的方法。     

一种新的基于Gabor小波的非监督纹理分割方法

提出了一种新的基于Gabor小波的非监督纹理分割方法,与传统Gabor方法相比,该方法最大的特点在于分割的过程中利用了纹理尺度之间的依存关系和像素之间的空间约束关系。为了克服增加特征所带来的"维数灾难"问题,用独立分量分析(ICA)进行特征的整合。采用Brodatz测试集的实验结果验证了方法的有效性。     

Quantitative relationship between surface sedimentary diatoms and water depth in North-Central Bohai Bay,China

To study the quantitative relationship between surface sedimentary diatoms and water depth, 67 surface samples were collected for diatom analysis on eight profiles with water depth variation from the muddy intertidal zone to the shallow sea area in North-Central Bohai Bay, China. The results showed that the distribution of diatoms changed significantly in response to the change in water depth. Furthermore, the quantitative relationship between the distribution of dominant diatom species, their a...