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101.
厦门经济特区城市发展与布局研究 总被引:1,自引:0,他引:1
陈怡煌 《云南地理环境研究》1991,3(1):74-82
厦门是座海岸一港岛复合型城市。为中国“经济特区—经济技术开发区—沿海经济开放区”有机结合带,它又是全国计划单列城市和福建改革开放综合试验区。多层次的对外开放和多元结构的改革试验,为区域开发、城市空间布局和多功能构建注入了新活力。台湾海峡两岸关系的改善使之成为投资热点,提高了它在完成祖国统一大业中的特殊战略地位。本文以地理学的观点,分析了世界经济特区的基本模式和中国经济特区城市的基本职能,探讨了厦门设置特区的因由、吸引腹地、城市性质、产业开发、城市空间格局,并对特区城市的高新技术开发作了初步论证。 相似文献
102.
对矿物沸腾包裹体若干问题的探讨 总被引:1,自引:0,他引:1
矿物沸腾包裹体是矿液处在沸腾相态下被矿物捕获的包裹体,它具有不同形态、不同大小、不同类型混乱产出的特征,包裹体溶液含盐度高,均一温度变化大,有些包裹体可能含有围岩碎屑。温度、压力、盐度是影响矿液沸腾的因素。研究沸腾包裹体有助于研究矿床形成的地质条件和矿液运移方式,可提供找矿信息。均一温度用所测数据两极值或中值作为成矿温度均不恰当,应以均一温度最小的液、气相包裹体的均一温度作为试样所在处的成矿温度较为适宜,成矿压力亦采用这种包裹体所测得的压力值作为代表较为恰当。 相似文献
103.
GS-15型重力仪是利用摆杆位移大小来量度重力相对变化的精密仪器,摆杆位移是通过电容换能进行测量。由于该仪器为开环检测系统,而且系统的末级加接0.01Hz的有源滤波器,这样就失去了大于0.01Hz的高频成分,且使潮波产生相位失真,同时还存在着电路非线性带来的测量误差,因而测量精度难以提高。为此笔者对GS-15型重力仪加装了电磁反馈装置,将开环检测改为闭环检测,利用电磁力使重力仪摆杆始终处于零电平的动态平衡状态,以电磁反馈输出大小来度量重力的变化,这样就将开环检测系统改装为平衡电桥闭环检测系统,其时间常数为2秒。 改装后,消除了电路的非线性影响,增强了系统的稳定性,记录的固体潮含有丰富的谐波,同时系统还增加了一路稳态零位输出,为地壳形变、地震预报和地球物理研究提供了波群丰富的资料 相似文献
104.
Summary
The most popular exploitation method used in Canadian hard rock mines is open stope mining. Geomechanical design of open stopes
relies on a range of analytical, numerical and empirical tools. This paper presents an engineering approach for the analysis
and the design of reinforcement for open stopes in jointed rock. The proposed methodology, illustrated by three case studies,
relies on developing 3D joint network models from field data. The 3D joint networks have been successfully linked to a 3D
limit equilibrium software package. The models account for the finite length of joints as well as the influence of random
joints. The integrated approach facilitates comparative analyses of different reinforcement strategies under different degrees
of jointing in the hard rock environment.
Received February 23, 2001; accepted October 11, 2002; Published online January 21, 2003
Acknowledgments The financial support of the National Science and Engineering Council of Canada and the Institut de Recherche en Santé et
Sécurité au Travail of Quebec and Noranda Inc. is greatly appreciated.
Authors' address: Prof. John Hadjigeorgiou, Université Laval, Department of Mining, Metallurgy and Materials Engineering, G1K 7P4 Quebec City,
Quebec, Canada; e-mail: john.hadjigeorgiou@gmn.ulaval.ca 相似文献
105.
LIVE-BED SCOUR IN LONG CONTRACTIONS 总被引:1,自引:0,他引:1
Subhasish DEY Rajkumar V. RAIKAR 《国际泥沙研究》2006,21(2):166-170
1 INTRODUCTION Scour within a channel contraction occurs where the waterway is restricted by the foundations or road approach embankments of a bridge. Alternately, contraction scour takes place when a bridge is located at a natural contraction in the rive… 相似文献
106.
Wave set-up in storm surges is studied using a numerical model for coasts in Tosa Bay, Japan, open to the Pacific Ocean. Simulation models employing only atmospheric pressures and winds as external forces are unable to properly simulate open coast storm surge heights, such as those due to Typhoon Anita (1970). However, the present study shows that a numerical model incorporating wave-induced radiation stresses, as well as wind stresses and pressure gradients, is able to account for the open coast surge heights. There is a maximum contribution of 40% by the radiation stresses to the peak sea level rises. This study also evaluates the effects of the tides; including the tides improves the agreement between the predicted water surface elevations and the observations. The difference in predictions between one-way coupling from wave to surge models and two-way coupling of the surge and wave models is found to be small. 相似文献
107.
动态分段思想在公路地理信息系统中的实现 总被引:7,自引:0,他引:7
动态分段是一种全新的线性特征的动态分析技术,可以有效地解决公路线性特征的动态分析问题,实现公路图形和属性数据间的双向动态可视化查询。文章以Arc/Info为代表,分析了动态分段技术的原理,结合VB6.0、MapObjects2.2和Access,初步介绍了公路GIS中动态分段的数据结构与算法,并探讨了如何实现公路GIS的过程。 相似文献
108.
Izhak Schnell 《GeoJournal》2007,69(4):257-269
Sheinkin is an example of a place constituted by global forces. Yet Sheinkin creatively responds to scalar jumps of global
forces, drawing from the capitals of the global system like Soho and Greenwich village. These models are embedded in the Israeli
reality with Sheinkin becoming an incubator of post-Zionist identity. Young people from all over Israel concentrate in the
place on Fridays to participate in choreography of strolling along the street with its’ designers’ shops, mingling with celebrities
and others who belong to the cult and around the ‘Hyde Park’ corner in which environmental, spiritual and other worldviews
are promoted. The article suggests a model to investigate such places as the organic integration of a community whose participants
do not live in the place but pilgrimage to the place, a landscape that appraises creativity, originality and individualism,
a choreography of strollers who search for stimulations and a set of norms and values promote in the place. 相似文献
109.
Applied Research Laboratories, The University of Texas at Austin (ARL:UT) has established a cross platform open source software
project called the GPSTk or the GPS Toolkit. The GPSTk consists of a library and collection of applications that support GPS
research, analysis, and development. The code is released under the terms of the Lesser GNU Public License. The GPSTk supports
a broad range of functionality. This includes reading and writing observations in standard formats, such as RINEX, BINEX,
and SP3, ephemeris evaluation, position determination, receiver autonomous integrity monitoring (RAIM), atmospheric delay
modeling, cycle slip detection and correction, and P-code generation. The GPSTk provides the core set of functionality that
is used for GPS research and development at ARL:UT. ARL:UT has been involved with satellite navigation since Transit (the
precursor to GPS) in the 1960s and is currently conducting research in a wide variety of GPS-related fields, including precise
surveys, monitor station networks, and ionospheric studies. The GPSTk is a community-wide resource for all users of GPS and
GNSS technology. Participation is welcomed in all areas including: bug reports, new algorithms, suggestions for improvement,
and contributions of additional functionality or applications. ARL:UT continually improves the library, shepherds community
participation, and is committed to the project’s development and maintenance.
The GPS Toolbox is a column dedicated to highlighting algorithms and source code utilized by GPS Engineers and scientists.
If you have an interesting program or software package you would like to share with our readers, please pass it along; e-mail
it to us at gps-toolbox@ngs.noaa.gov. To comment on any of the source code discussed here, or to download source code, visit
our website at . This column is edited by Stephen Hilla, National Geodetic Survey, NOAA, Silver Spring, Maryland, and Mike Craymer, Geodetic
Survey Division, Natural Resources Canada, Ottawa, Ontario, Canada. 相似文献
110.
David A. Greenberg Frédéric Dupont Florent H. Lyard Daniel R. Lynch Francisco E. Werner 《Continental Shelf Research》2007
The baroclinic and barotropic properties of ocean processes vary on many scales. These scales are determined by various factors such as the variations in coastline and bottom topography, the forcing meteorology, the latitudinal dependence of the Coriolis force, and the Rossby radius of deformation among others. In this paper we attempt to qualify and quantify scales of these processes, with particular attention to the horizontal resolution necessary to accurately reproduce physical processes in numerical ocean models. We also discuss approaches taken in nesting or down-scaling from global/basin-scale models to regional-scale or shelf-scale models. Finally we offer comments on how vertical resolution affects the representation of stratification in these numerical models. 相似文献