天然地震折射与反射速度CT的模型实验

为提高天然地震折射与反射速度CT的精度,我们运用“走时最小纵横波速度层析成像”与“波形基本解纵横波速度层析成像”相结合的方法,反演各层界面形状及各层纵波、横波速度。反演结果图与“正演地球模型剖面图”基本一致。本文在数学上发展了“层析成像”的内容,提出“波形基本解纵横波速度层析成像”基本概念,是天然地震简单模型实验的初步尝试,偏重于理论研究,其理论和方法有一定参考价值。天然地震比人工地震复杂,模型实验不足之处,与实际应用有距离,后续论文将给予补充并处理实际天然地震资料。     

Time and Practice: Learning to Become a Geographer

Abstract

Illustrated Dictionary of Place Names: United States and Canada. By Kelsie B. Harder. New York: Van Nostrand, 1976. Pp. xiv + 631, $18.95.

Middle America: Its Lands and Peoples. 2nd ed. By Robert C. West and John P. Augelli. Englewood Cliffs, N.J.: Prentice-Hall, 1976. Pp. xvii + 494, $14.95.

Contemporary Africa: Geography and Change. Edited by C. Gregory Knight and James L. Newman. Englewood Cliffs, N.J.: Prentice-Hall, 1976. Pp. xiv + 546, $14.95.

Atlas of Mexico. By Stanley A. Arbingast et al. 2nd ed. Austin, Tex.: Bureau of Business Research, University of Texas, 1975. Pp. ix + 165, $15.00.

Readings in Social Geography. Edited by Emrys Jones. London: Oxford University Press, 1975. Pp. 328, $18.50 and $6.95.

California: Patterns on the Land. 5th ed. By Robert Durrenberger and Robert Johnson. A California Council for Geographic Education Publication. Palo Alto, Calif.: Mayfield Publishing, 1976. Pp. viii + 134, $6.95.

Studying China in Elementary and Secondary Schools, Studying India in Elementary and Secondary Schools, and Studying Japan in Elementary and Secondary Schools. By Leonard S. Ken-worthy. World Affairs Guides. New York: Teachers College Press, 1975. Pp. 68, iii + 67, and iii + 65, $2.75 each.

World Regional Geography: A Question of Place. By Paul Ward English and James Andrew Miller. Harper &; Row Series in Geography. New York: Harper &; Row, 1977. Pp. xiii + 591, $15.95.

Census Data: Geographic Significance and Classroom Utility. Edited by Borden D. Dent. Tualatin, Oreg.: Geographic and Area Study Publications, 1976. Pp. ix + 277.

The Middle East: A Geographical Study. By Peter Beaumont, Gerald H. Blake, and Malcolm J. Wagstaff. London: John Wiley &; Sons, 1976. Pp. xvii + 572, $25.50 and $14.95.

Man's Economic Environment. By Edgar C. Conklingand Maurice Yeates. New York: McGraw-Hill Book Co., 1976. Pp. xi + 308, $11.95.

Applied Climatology: An Introduction. 2nd ed. By John F. Griffiths. New York/London: Oxford University Press, 1976. Pp. xiii + 136, $9.00.

Man and the Environment: Regional Perspectives. Edited by J. H. Holmes. Hawthorn, Victoria: Longman Australia Pty Limited, 1976. Pp. vi + 261, $7.95.

Introduction to Cultural Geography. 5th ed. By Henry M. Kendall, Robert M. Glendinning, Clifford H. MacFadden, and Craig H. MacFadden. New York: Harcourt Brace Jovanovich, 1976. Pp. xx + 449, $12.95.

Interpretation of Aerial Photographs. 3rd ed. By Thomas Eugene Avery. Minneapolis, Minn.: Burgess Publishing Company, 1977. Pp. xi + 392, $14.95.

Geography of the U.S.S.R. 3rd ed. By Paul Lydolph. New York: John Wiley &; Sons, 1977. Pp. xi + 495, $18.95.     

四平山门—放牛沟一带成矿系列及成矿区带划分

山门—放牛沟一带分布有众多的贵金属、多金属矿床(点),是吉林省重要的成矿区带之一,本文根据前人的工作成果,总结了该区的成矿地质背景和成矿系列,并在全国Ⅲ级成矿区带划分的基础上进行了Ⅳ级成矿亚带的划分,对各成矿亚带的特征进行了总结。     

Predicting ground-motion variations at the Turkey-flat test site,California

Results of a single group participating in an international experiment are analyzed. The experiment served to verify computational predictions of the ground-motion variations due to near-surface geological effects at a site established for that purpose by the California Department of Conservation. Based on an acceleration record at a rock location, and geotechnical model of medium, records at the other locations of a nearby sedimentary deposit were predicted. A 2-D finite-difference sensitivity analysis suggested that the lateral wave-propagation effects are negligibly small, and locally 1-D computations are sufficient for the present site. Those computations are compared with observations not available to the authors during the blind prediction. Peak accelerations, peak velocities and RMS accelerations were predicted with errors less than 159%, 114% and 62%, respectively. Maxima of the response spectra were fitted within a factor of 2. The predicted and observed Husid's plots (i.e., the normalized cumulative plots of the acceleration squared) have the correlation coefficients 0.98. The detected misfits do not show any simple relation to the instrument location, component, frequency, or time.     

Detection of spatio-temporal evolutions on multi-annual satellite image time series: A clustering based approach

The expansion of satellite technologies makes remote sensing data abundantly available. While the access to such data is no longer an issue, the analysis of this kind of data is still challenging and time consuming. In this paper, we present an object-oriented methodology designed to handle multi-annual Satellite Image Time Series (SITS). This method has the objective to automatically analyse a SITS to depict and characterize the dynamic of the areas (the way that the land cover of the areas evolve over time). First, it identifies the spatio-temporal entities (reference objects) to be tracked. Second, the evolution of such entities is described by means of a graph structure and finally it groups together spatio-temporal entities that evolve similarly. The analysis were performed on three study areas to highlight inter (among the study areas) and intra (inside a study area) similarity by following the evolution of the underlying phenomena. The analysis demonstrate the benefits of our methodology. Moreover, we also stress how an expert can exploit the extracted knowledge to pinpoint relevant landscape evolutions in the multi-annual time series and how to make connections among different study areas.     

近百年中国地表气温变化趋势的再分析

重新考虑了1950年前后器测资料的非均一性问题,统一采用最高温度和最低温度计算月平均温度,利用国际上通行的区域平均温度序列计算方法,建立了中国近100年的地表气温序列,并对气温变化趋势进行了再分析.结果表明,自1905年以来中国地表年平均气温明显增暖,升高幅度约为0.79℃,增温速率约为0.08℃/10 a,比同期全球或北半球平均略高.但是,20世纪80年代初以来的增温似乎不比30～40年代明显,而20世纪50～60年代地表气温的变冷却比全球或北半球显著得多.和全球平均温度变化一样,近100年来中国的增温也主要发生在冬季和春季,而夏季却有微弱变凉趋势.新的全国平均气温序列与以往的研究结果比较给出了更高的增温趋势估计值,这主要与采用新的月平均气温统计方法改善了原序列的均一性有关.另一方面,由于早期资料覆盖面积比例低和后期城市化影响等问题,这里给出的增温趋势估计仍然存在着较大的不确定性.     

江苏省冬小麦播种期对气候要素变化的响应

利用江苏省35个气象台站1961- 2009年冬小麦播种期内的气象观测资料,采用数理统计方法,分析了近49 a来冬小麦播种期内各气候要素的变化.结果表明:江苏省冬小麦主要播种期内的日平均气温随着时间的推移逐渐升高,且相关显著,其中淮河以南地区升高速度更快;秋季稳定通过15℃的终日总体呈逐年推迟趋势,尽管部分年际间波动较大;按传统播期播种到越冬的≥0℃有效积温与年序也呈极显著正相关关系.分析沭阳、淮安、盱眙、滨海、赣榆和徐州6个农业气象观测站的冬小麦发育期资料,及当地冬小麦播种至越冬前积温资料.结果表明:各地冬小麦播种至越冬≥0℃有效积温总体上逐年增加.此外,冬小麦播种期内降水量的波动较大,尤其自1990s中期以来,各地降水量呈逐年递减趋势.得出结论:江苏省冬小麦应适时晚播,并应趁墒及时播种.     

Neural Network-Based Active Control for Offshore Platforms

1 .IntroductionWiththedevelopmentofoceantechnology ,moreandmoreextremelylargeandlongflexibleoff shoreplatformsusedforoilexplorationanddrillingoperationarebuiltinhostileoceanenvironments .Ingeneral,thiskindofplatformsisanonlineardistributedparametersystemanditsnaturalfrequencyfallsclosertothedominantwavefrequencieswiththeincreaseofwaterdepth .Besides ,itsstructureisverycomplexandtheexternalwaveforceontheplatformisuncertain .Thus ,theseplatformsarepronetoexcessivewave inducedoscillationsunderbot…     

胜利油气区有机包裹体研究及其在油气勘探中的应用

应用显微光度术、显微傅立叶红外光谱（Ｍｉｃｒｏ－ＦＴ．ＩＲ）和飞行时间二次离子质谱（ＴＯＦ－ＳＩＭＳ）等原位微分析技术并结合均一温度测量对胜利油气区下第三系沙河街组沙三段中有机包裹体进行了研究。区分出两类有机包裹体，即原生有机包裹体和次生有机包裹体。结果表明两类有机包裹体特征不同，二者物质组成、有机质成分及化学结构、热演化程度等差别也较大。结合地质分析表明原生有机包裹体是沙三段烃源岩生成烃类运移产物，具“自生自储”特点，而次生有机包裹体是沙四段烃源岩生成的烃类二次运移的产物。沙三段是沙河街组油气运移和聚集的主要层位，因而是寻找油气资源的主要目标层。研究表明，有机包裹体是研究油气生成、运移、聚集和演化等成藏系统最有效的手段之一，在油气勘探中有重要的应用意义。     

Identification of Fei-Tsui arch dam from both ambient and seismic response data

This purpose of this paper is to study the dynamic characteristics of the Fei-Tsui arch dam using the seismic response data and the ambient vibration data. For the identification of dam properties from seismic response data, the multiple inputs from the abutment of the dam to represent the nonuniform excitations of seismic input motion are considered, and the ARX model is applied using the discrete-time linear filtering approach with least-squares approximation to identify the dynamic characteristics of the dam. The system modal dampings, natural frequencies and frequency response functions are identified. A comparison of the identified modal parameters is made among different seismic events. Post-earthquake safety evaluation of the dam can be made based on the identified model. Finally, the ambient vibration test of the dam is performed to identify the mode shapes along the dam crest.