公路放样中曲线定线方法的探讨

介绍了公路放样中直接定线的几种方法,并给出了详细的实施步骤,供施工放样人员参考.     

民用建筑物主轴线的放样方法

城市中民用建筑物主轴线的放样（定位）是实施城市规划的重要环节。本文介绍了几种实用的放样方法，经多次实践，认为这些方法非常有效。建筑物主轴线的放样方法，按放样依据点及现场地形条件，可分类为：依规划红线放样，依道路中线放样，依坐标放样和依原有建筑物放样等。现结合实例分别叙述。     

GPS-RTK技术在荆岳大桥钢护筒放样中的应用

介绍了荆岳大桥钢护筒施工放样方法与精度要求,以及阐述了GPS-RTK在钢护筒放样中的作业过程,分析了GPS-RTK放样精度,实现了钢护筒放样.     

浅析偏心放样测量的原理及应用

目前在工程测量中,全站仪已得到了广泛的应用,基于全站仪在工程放样应用中的某些方面的不足,本文提出了一种新的放样方法,并介绍其放样原理和精度分析,通过实际放样过程中的工程事例介绍,来说明这种放样方法在不同精度要求的工程中施行的可行性。     

建筑施工中放样点平面位置的精度分析

建筑工程施工测量贯穿于建筑施工的始终,其测量的精度如何,直接关系到整个建筑工程建设的速度和工程的质量.从施工控制网的精度要求,放样方法的精度、工程特点对放样方法选择的要求等方面,对建筑工程定位放线中如何减小误差进行了分析,探讨了施工测量中提高放样精度方法.     

公路放样中曲线定线方法的探讨

介绍了公路放样中直接定线的几种方法，并给出了详细的实施步骤，供施工放样人员参考。     

参考线法测设在大坝加高工程中的应用

阐述了参考线法,即建立一个自由平面直角坐标系,根据放样点位的相对位置进行放样.分析参考线法与传统放样方法的不同之处,介绍参考线法实施步骤,并以实例说明了参考线法测设在大坝加高工程中的应用情况.     

路堑边坡桩放样程序的设计与应用——适用于CASIOfx-4800P计算器

从目前道路工程建设对路堑边坡桩放样的要求入手,分析目前常用路堑边坡桩放样方法的局限性,提出一种基于全站仪和计算器程序支持的路堑边坡桩放样方法,介绍程序设计思路及内容,在实践中得出该方法全面、适时、快捷、准确的特点。     

千寻位置CORS-RTK在建筑基坑放样中的应用

针对目标放样区被围墙遮挡,基准站架设点位于道路中央的情况下,无法使用传统的全站仪放样法和单连续运行参考站-实时动态(CORS-RTK)放样法的问题. 采用了千寻位置服务系统,利用网络CORS-RTK方法进行工程建设中基坑的放样,介绍网络连续运行参考站(CORS)的原理及优点,对放样点数据进行处理,分析了放样精度. 结果表明通过RTK测得37个放样点平面坐标, X 方向中误差在20 mm之内的点占97 ％, Y 方向中误差在20 mm之内的点占100 ％,比较集中稳定;点位中误差小于20 mm的占95％,在20～40 mm占5％, CORS-RTK方法的测量点位中误差均满足国家《卫星定位城市测量技术规范》CJJTT73-2010要求的平面点位中误差小于70 mm的精度要求.千寻的CORS测量符合工程规范精度要求,对减少工程施工放样的工作量具有重要意义.      

全站仪偏心放样测量新方法及其可靠性

目前在工程测量中,全站仪已得到了广泛的应用,基于全站仪在工程放样应用中要求测站点与待放样点必须通视,而在实际工作中这两点常常是不通视的,提出了一种新的全站仪放样方法,详细论述了放样原理、精度以及可靠性,并依托大唐桂冠合山发电有限公司2×600 MW级机组上大压小工程主厂房桩基A标工程项目,论证了该方法放样结果的内符合与...     

Pinpointing the sources and measuring the lengths of the principal rivers of the world

Abstract

Cultures throughout the world are associating with the rivers. People depend upon the rivers and their tributaries for food, water, transport, and many other aspects of their daily lives. Unfortunately, human beings have not calculated the accurate lengths for the great rivers even today. The lengths of the rivers are very different in popular textbooks, magazines, atlases and encyclopedias, etc. To accurately determine the lengths of the principal rivers of the world, the combination of satellite image analysis and field investigations to the source regions is proposed in this paper. The lengths of the Nile, Amazon, Yangtze, Mississippi, Yellow, Ob, Yenisey, Amur, Congo and Mekong, with lengths over or close to 5000 km, were calculated using the proposed method. The results may represent the most reliable and accurate lengths of the principal rivers of the world that are currently achievable.     

世纪之交的沉思--论21世纪软科学的发展

软科学这一术语是70年代在国外提出的.然而30多年以来,它在国外不仅未得到普遍的承认,而且对软科学的定义也还未能达成大体上一致的共识.而在改革开放后的中国,出于决策科学化和民主化的需要,经过一些领导人的提倡和支持,特别是通过1986年召开的软科学座谈会及1994年召开的全国软科学工作会议,软科学事业得到了蓬勃的发展.据初步统计,截止1998年底全国共有软科学研究机构1224个,研究人员32655人,初步形成了一支较为强大的研究队伍,并取得了数百项覆盖多个领域的研究成果,为支持各级各类的决策发挥了一定的作用.     

Improving the modeling of the atmospheric delay in the data analysis of the Intensive VLBI sessions and the impact on the UT1 estimates

The very long baseline interferometry (VLBI) Intensive sessions are typically 1-h and single-baseline VLBI sessions, specifically designed to yield low-latency estimates of UT1-UTC. In this work, we investigate what accuracy is obtained from these sessions and how it can be improved. In particular, we study the modeling of the troposphere in the data analysis. The impact of including external information on the zenith wet delays (ZWD) and tropospheric gradients from GPS or numerical weather prediction models is studied. Additionally, we test estimating tropospheric gradients in the data analysis, which is normally not done. To evaluate the results, we compared the UT1-UTC values from the Intensives to those from simultaneous 24-h VLBI session. Furthermore, we calculated length of day (LOD) estimates using the UT1-UTC values from consecutive Intensives and compared these to the LOD estimated by GPS. We find that there is not much benefit in using external ZWD; however, including external information on the gradients improves the agreement with the reference data. If gradients are estimated in the data analysis, and appropriate constraints are applied, the WRMS difference w.r.t. UT1-UTC from 24-h sessions is reduced by 5% and the WRMS difference w.r.t. the LOD from GPS by up to 12%. The best agreement between Intensives and the reference time series is obtained when using both external gradients from GPS and additionally estimating gradients in the data analysis.     

Movements of the protoplanetary superconducting particles in the magnetic field of the Saturn lead to the origin of the rings

In this letter, we are trying to resolve the electromagnetic problem for the movements of the superconducting particles of the protoplanetary cloud in the magnetic field of Saturn. The force of levitation (Meissner-Ochsenfeld phenomenon) is introduced to the field of planetary science for the first time. It is shown from our theoretical analysis that rings of Saturn might have a superconducting origin, and rings might levitate within magnetic equator plane of the planet.     

省直管市（县）体制下建设用地监管技术研究

面向解决省直体制下市（县）建设用地管理业务监管难度大问题,研究建设用地全过程监管关键技术,设计该模式下的监管模式、技术架构、业务模型和数据模型,实现省直管市（县）模式下的建设用地批前、批中、批后＂批-供-用-补-查-登＂全过程监管。     

GPS整周模糊度确认中残差二次型次小与最小之差的分布问题

根据残差二次型次小与最小之差进行整周模糊度确认的关键是差值的分布,只有得到了合理的差值分布才可确定合理的界值.文中基于原有的两种方法及这两种方法的不足,从理论上导出了满足条件的差值分布,并作了一定的说明.