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EduardoF.J.deMulder 《《幕》》2004,27(1):2-2
Disseminating scientific knowledge has always been a key topic in IUGS‘ activities. The Union has produced a range of publications (books, journals, maps, charts), both on its own and in cooperation with other organizations and publishers.Some of these works have been concerned with geological standards, while others have been overviews of current topics, 相似文献
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Mathematical models applied to urban and regional planning have been widely developed during the sixties. Since that time
the scientific and technologic developments have deeply transformed the field of spatial modelling. There has been a reaction
against the idea that reality could be reduced to deterministic models. The paradigms of complexity, chaos, self-organisation,
fractal geometry have made obvious the unpredictability of complex socio-economic systems. At the same time the progress of
computation has led to the substitution of simulation methods to analytic solutions of mathematical models. In such a context,
models are loosing in generality and reproducibility what they earn in adaptation to empirical situations. An important challenge
is also to confirm the pertinence and specificity of the geographical approach. In that respect the spatial analysis programs
must prove the evidence of a common methodology dealing either with physical or human and economic domain. We are working,
for instance, on cellular automata programs applied to the historical evolution of an urban space and also to the run-off
process in an elementary basin. The spatial structure of the models may be slightly different: rectangular or hexagonal tessellations
in the “Human Geography” program, TIN structure, closer to the physical reality, in the other. The relations between the cells
may also differ: they are often defined by a distance matrix for the socio-economic models, but a contiguity matrix is of
course needed for the streaming process. But, beyond these technical differences, it appears that the geographical programs
are developed on a macro-level, that is on aggregate statistical units. The elementary particle is always (or should be for
a geographer...) a material, spatial unit, unlike the drop of water of the hydrologists, or the individual “agents” of the
sociologists' multi-agents systems. The difference between the micro and macro level is not a question of scale, but a difference
of logic. The simulation approach has a requisite, which is a need of systematic validation by a permanent comparison with
the actual situation, but the objective is not prediction. The scientific concern is, before all, a precise understanding
of the past and recent evolutions, more than a forecasting, which escapes to the specific field of scientific research. What
is scientific is what can be measured. The possible prediction may rely on the scientific research, but belongs strictly to
the domain of intellectual and personal thinking.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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任何人都不可能脱离资源条件和生产力发展水平,来选择建筑形式或居住方式。义乌在新村建设中,从建别墅群到建公寓楼,在实践中探索适合自己条件的新村建设之路。农村经济的迅速发展、农村正在发生的深刻变化和城乡一体化进程,为节地型新村建设提供了难得的机遇。建设节地型新村的关键,在于将由此创造出的效益,合理地分配给农民。 相似文献
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From rocks to ore 总被引:1,自引:0,他引:1
Metal enrichment to ore grade is the ultimate outgrowth of large-scale and long-term fractionation processes of the thermally
driven and unique water-cooled geological evolution of the Earth. Silicic magmatism along convergent margins is the most important
lithospheric fractionation process for the formation of the continental crust and porphyry/intrusion-related ore deposits.
Reconnaissance microanalysis of melt inclusions from Central Andean porphyry systems refines a metallogenic model for copper–gold
and tin porphyry mineralization. Magmatic mixing and early exsolution of a fluid phase are important ingredients for porphyry
Cu–Au systems in association with silicic rocks of moderate levels of fractionation (such as diorites and monzonites), whereas
extended magmatic fractionation with late-stage fluid evolution characterize lithophile-element-enriched tin porphyry systems.
Received: 25 June 1999 / Accepted: 11 January 2000 相似文献
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1932—1937年间在周口店中国猿人产地及其他地点采得八十馀件节足动物化石,多破碎,完整者极少。颜色不一,由乳白而棕黄,兼有呈半透明玻璃状者。经初步观察,应属节足动物门,多足纲,倍脚目,马陆科,计一属两种: 一、山马陆(Julus of.terrestris)此种在第一,三,十五地点及山顶洞均有发现。此与现生的山马陆无甚差异,仅肛板及由二肛板所成之肛门沟稍大。二、裴氏小马陆(Julus peii Chia & Liu(sp.nov.)此种於第一,四,十五地点及山顶洞均有发现。由身体及头部形态,身体环节数目(三十个以上),知其与山马陆同属。但其决非幼小山马陆,因其体节数目多於长成之山马陆。但与现生於日本的一种 Nipponoiulus truncatus 近似,惟後者体节数较少,尾端钝圆。关於马陆属化石,据现在所知最早发现於始新统地层中,直到现在仍有生存,变异极小。以上所述二种若非与其他脊椎动物化石共生於周口店地点,则其年代颇难鉴定,因其有以後爬入岩隙死後石化之可能,不过上述之标本不但有共生脊椎动物为证,且有的已埋藏於固结的砾岩中,其属於更新统时期可无疑义。 相似文献
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1932—1937年间在周口店中国猿人产地及其他地点采得八十馀件节足动物化石,多破碎,完整者极少。颜色不一,由乳白而棕黄,兼有呈半透明玻璃状者。经初步观察,应属节足动物门,多足纲,倍脚目,马陆科,计一属两种: 一、山马陆(Julus of.terrestris)此种在第一,三,十五地点及山顶洞均有发现。此与现生的山马陆无甚差异,仅肛板及由二肛板所成之肛门沟稍大。二、裴氏小马陆(Julus peii Chia & Liu(sp.nov.)此种於第一,四,十五地点及山顶洞均有发现。由身体及头部形态,身体环节数目(三十个以上),知其与山马陆同属。但其决非幼小山马陆,因其体节数目多於长成之山马陆。但与现生於日本的一种 Nipponoiulus truncatus 近似,惟後者体节数较少,尾端钝圆。关於马陆属化石,据现在所知最早发现於始新统地层中,直到现在仍有生存,变异极小。以上所述二种若非与其他脊椎动物化石共生於周口店地点,则其年代颇难鉴定,因其有以後爬入岩隙死後石化之可能,不过上述之标本不但有共生脊椎动物为证,且有的已埋藏於固结的砾岩中,其属於更新统时期可无疑义。 相似文献
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Uncertainty in Measurements of Vibrations From Blasting 总被引:1,自引:0,他引:1
Pablo Segarra Lina M. López José A. Sanchidrián 《Rock Mechanics and Rock Engineering》2012,45(6):1119-1126
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对中国工程设计企业而言,资质源于计划经济,品牌则存在于成熟的市场经济;资质的实质是行业壁垒,品牌的实质则是差异化竞争。在全球经济一体化背景下,伴随着市场的成熟和业主的成熟,从资质管理到品牌管理,无疑将成为工程设计企业寻求可持续发展的战略选择。 相似文献
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Prof. Dr. Aart Brouwer 《International Journal of Earth Sciences》1981,70(1):33-39
A slim volume by EduardSuess (1875) exercised a profound influence in France, where particularly MarcelBertrand was stimulated by the concept of horizontal forces involved in the formation of mountain chains. Others in France (Termier, Haug) and in Switzerland (Lugeon, Schardt, Argand) followed in his steps, and eventually their researches lead to the establishment of the nappe theory in the Alps. It was EmileArgand (1924) who linked the nappe theory withWegener's theory of continental drift, and in doing so laid the foundation for a more general theory of crustal mobility.
Zusammenfassung Ein kleines Buch von EduardSuess (1875) hat einen tiefen Einfluß ausgeübt in Frankreich, wo besonders MarcelBertrand angeregt wurde von den Gedanken über horizontale Kräfte in der Entstehung von Gebirgsketten. Andere in Frankreich (Termier, Haug) und in der Schweiz (Lugeon, Schardt, Argand) traten in Bertrands Fußstapfen, und ihre Forschungen führten zur Gründung der Deckentheorie in den Alpen. EmileArgand (1924) hat dann die Deckentheorie mitWegeners Verschiebungstheorie verknüpft und damit die Grundlage geschaffen für eine allgemeine Theorie der krustalen Mobilität.
Résumé Un petit volume d'EduardSuess (1875) a exercé une influence profonde en France où notamment MarcelBertrand fut stimulé par l'idée des mouvements horizontaux dans la génèse des chaînes de montagnes. D'autres marchèrent sur ses traces (Termier etHaug en France,Lugeon, Schardt etArgand en Suisse), et leurs recherches dans les Alpes conduisirent à la théories des nappes. Plus tard EmileArgand (1924) a relié la théorie des nappes à la théorie de la dérive continentale et par là jeté les fondements d'une théorie générale de la mobilité crustale.
(1875) , a Marcel Bertrand . (Termier, Haug) (Lugeon, Schardt, Argand) . Emil Argand (1924)相似文献
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从同位素年代学发展到构造年代学 总被引:1,自引:0,他引:1
从同位素年代学发展到构造年代学,中间必需经历热年代学、构迼-热年代学和变形年代学等阶段。同位素年代学只是提供简单的地质事件年龄,热年代学使年龄赋予了温度的信息,而构造年代学则强调地质或构造过程时间-空间的四维演化过程。构造年代学使年龄数据的科学意义除了时间,还有温度、地壳深度变化以及流体的是否参与等多重意义,它涉及到多维空间的变化:时间、温度、水平方向的二维变形、垂直方向的变形等。在现有技术和认知水平的条件下,作者强调指出了从变形年代学到构造年代学的发展中要注意的一些关键的问题,而回归传统地质、以野外变形为基础的变形年代学研究是构造年代学发展的前提。 相似文献
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Coalbed methane: From hazard to resource 总被引:4,自引:0,他引:4
Coalbed gas, which mainly consists of methane, has remained a major hazard affecting safety and productivity in underground coal mines for more than 100 years. Coalbed gas emissions have resulted in outbursts and explosions where ignited by open lights, smoking or improper use of black blasting powder, and machinery operations. Investigations of coal gas outbursts and explosions during the past century were aimed at predicting and preventing this mine hazard. During this time, gas emissions were diluted with ventilation by airways (e.g., tunnels, vertical and horizontal drillholes, shafts) and by drainage boreholes. The 1970's ‘energy crisis' led to studies of the feasibility of producing the gas for commercial use. Subsequent research on the origin, accumulation, distribution, availability, and recoverability has been pursued vigorously during the past two decades. Since the 1970's research investigations on the causes and effects of coal mine outbursts and gas emissions have led to major advances towards the recovery and development of coalbed methane for commercial use. Thus, coalbed methane as a mining hazard was harnessed as a conventional gas resource. 相似文献