PSD位置测量系统的实现及技术问题探讨

介绍了ＰＳＤ光电位置传感器及其测量系统的构成，并对位置测量系统中应着重考虑的技术问题进行了较深入的讨论，同时介绍了测量系统的其它应用领域．     

方向前方交会严密精度评定方法的研究

本文地针对方向前方交会精度评定中的不足之外，推导出了二测站和三测站方向前方交会同时考虑测量误差和测站点位误差时交会点严密的精度评定公式，从理论上完满地解决了方向前方交会的精度评定问题。     

华北蓟县元古界长城系串岭沟组岩石的古地磁再研究

华北蓟县剖面串岭构组5个点37个样品的热退磁再研究成果,获得极位为239.1°E和22.2°N,k=82,A₉₅=8.5°,落在已建立的蓟县元古界的视极移轨迹的常州组极和团山子组极之间连线附近,合理而可信.结果还表明测试的(次)火山岩与沉积岩是准同生的,可用作钻石U-Pb法测年对象.     

毫米级地球参考系面对的一些地球动力学问题

针对90年代天文地球动力学对地球参考系提出的毫米级要求,本文提出了一些更深入、更广泛的地球动力学问题,并探讨了可能的改进和解决方法。这些问题是:板块运动模型的改进;区域性地壳形变的影响;冰期后地壳回弹的影响;地球质心变化的影响。     

A comment on the use of spectral characteristics of teleseismic body waves to evaluate fine crustal structure

An investigation of the crustal response in the time and frequency domains is presented to show that for models with similar crustal transit times of P and S waves, any important changes in the internal configuration of the crust such as layering, layer thickness and velocity contrast only influence the amplitudes of the transfer function ratio. Frequency positions of peaks and troughs remain unperturbed unless the total transit time of P and/or S waves through the crust are varied. This would imply that fine crustal structure derived from a matching of peak positions of observed spectral ratios with theoretical transfer function ratios, as is commonly practiced, is not very meaningful. This limitation in the application of the spectral ratio method for detailed crustal structure is demonstrated using two recent applications of this technique.     

线元点位误差带的“纺锤形”模型

对当前GIS界流行的以点位误差描述线元位置不确定性的误差带理论提出相反的观点。最早提出的线元误差带理论为"ε-带"模型,后来又提出了"E-带"模型和在其基础上发展的"G-带"模型。后两者均认为以控制点点位误差描述的线元的误差带的基本形状呈"哑铃"形,即认为线元上端点的位置不确定性大于端点之间的点的位置不确定性。笔者的看法与此相反,笔者认为线元上两控制点之间的点的位置不确定性应大于控制点的位置不确定性,且在两控制点的中间达到最大,即线元误差带的基本形状应为"纺锤形"而不是"哑铃形"。     

地貌基本形态的主客分类法

针对现有地貌基本形态分类法的欠缺，提出了“地貌基本形态的主客分类法”。本分类法是一种以相对高度为主，绝对高度为辐的地貌分类法。它首先根据相对高度将地貌基本形态划分为平原、丘陵、低山，中山和高山等，然后再按绝对高度把这些形态再分别划分为低位、中位、高位三种类型。该地貌分类法的优点在于①符合人们对于山地的高、中、低的观念，避免了现有地貌分类法中出现的那种与人们固有观念相冲突的高山不高、低山不低的现象；②统一了地貌基本形态的划分标准，避免了平原、丘陵按相对高度划分，而山地按绝对高度划分的不一致性；③有利于地貌知识的科学普及和地貌的利用。     

GIS中三维空间直线的误差熵模型

从信息熵的角度提出了三维空间直线的误差熵模型，该模型由以垂直直线的平面误差熵为半径的圆柱体和两端点的误差球组成，是一种完全确定的度量空间线元不确定性的模型。理论分析与实验表明，本文所提出的模型具有较好的效果。     

Increasing ore extraction by changing detonator positions in LKAB Malmberget mine

By studying the charging plan of a ring and analysing the propagation of the stress waves caused by blasting in sub-level caving, the effects of detonator positions on ore fragmentation and ore extraction were investigated. Two detonator positions were studied and compared with each other. (1) Detonators were placed at the lowest charged position in a blast hole. This position is used in daily production blasting in Malmberget mine, and a ring with the lowest detonator position is called ordinary ring. (2) Detonators were placed at the middle of a charged blast hole, and a ring with such a detonator position is called a test ring. The study on charging plan and the analysis on stress wave propagation showed that a test ring has the following advantages over an ordinary ring: (a) fewer not-detonated (or initiated) blast holes in a ring; (b) more detonation energy utilized; (c) less back breakage to “eye brow”; (d) better fragmentation; (e) more ore extraction. On the basis of the above analysis, a total of 40 test rings have been tried and the ore extraction in the 40 rings has so far been finished in the mine. Correspondingly, the results from production indicate that: (1) The success rate of the detonated blast holes has been up to 91% according to our measurements to 16 test rings. (2) Severe back breakage has been avoided and common back breakage has been reduced in the test rings. (3) Fragmentation is much better, compared with the ordinary rings. (4) The average ore extraction from all of the test rings is increased by 107%, compared with that from the ordinary rings in the same drifts. Particularly, the lowest ore extraction from the test rings is increased by 80%, compared with that from the ordinary rings. (5) The iron content in extracted ore from the test rings is increased by 7.2% on average, compared with that from the ordinary rings.