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1.
This study presents a method of obtaining asymptotic approximations for motions near a Lagrange point in the planar, elliptic, restricted three-body problem by using a von Zeipel-type method. The calculations are carried out for a second-order escape solution in the proximity of the equilateral Lagrange point, L 4, where the primaries' orbital eccentricity is taken as the small parameter .  相似文献   
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Şenik  Berfin  Uzun  Osman 《Natural Hazards》2021,105(2):1587-1602
Natural Hazards - Open green spaces contribute to urban/rural life in terms of ecological, recreational, spatial, economic, etc., functions as well as prevention of natural disasters, mitigation of...  相似文献   
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Two main schools of thought in global tectonics are recognized during the first half of the XXth century on the basis of their proponents' attitude towards the principle of uniformitarianism and their belief in an inherent order and regularity vs. disorder and irregularity in tectonics. One group, here called the Wegener-Argand school, had a unifomitarian approach to global tectonics and believed in an inherently irregular Nature, in which probability rather than determinism was believed to be a realistic approach. The other, here called the Kober-Stille school, was largely non-uniformitarian (neocatastrophist) and believed in an orderly, regular Nature. These two schools correspond to Argand's mobilists and fixists respectively. In this paper I show that Eduard Suess was a convinced uniformitarian as far as his views on global tectonics are concerned and denied any inherent regularity in tectonic phenomena, temporal or spatial. In his interpretations of the causes and nature of orogeny, nature of geosynclines, and causes and nature of stabilisation, Suess appears to be the predecessor of the Wegener-Argandians, i. e. of the mobilists and not of the Kober-Stilleans as hitherto assumed. Although he remained a fixist and contractionist to the end Suess seems to have paved the way for the mobilists much as he did for the nappists during the last quarter of the XIXth century.
Zusammenfassung Während der ersten Hälfte des XX. Jahrhunderts kann man zwei globaltektonische Denkungsweisen oder Großschulen unterscheiden, die gekennzeichnet sind durch ihre Stellungnahme zum aktualistischen Prinzip in der Tektonik und ob sie an eine ordentliche und regelmäßige Natur glaubten oder nicht. Die erste, hier die Wegener-Argand-Schule genannt, hatte die Gültigkeit des aktualistischen Prinzips in der Tektonik anerkannt und die Natur, im Grunde genommen, als unordentlich und unregelmäßig betrachtet. Die Anhänger dieser Denkweise glaubten, daß probablistische Lösungen tektonischer Probleme realistischer seien als deterministische. Die andere Großschule, hier die Kober-Stille-Schule genannt, war im Grunde genommen anti-aktualistisch (Neo-Katastrophistisch) und glaubte, daß die Natur ordentlich und regelmäßig sei. Diese zwei Schulen entsprechen Argands' Einteilung in Mobilisten und Fixisten. In diesem Artikel zeige ich, daß E. Suess ein überzeugter Aktualist in bezug auf seine tektonischen Ansichten war, und daß er jede Regelmäßigkeit, zeitlicher oder räumlicher Art, der tektonischen Ereignisse ablehnte. In seinen Interpretationen der Ursachen und der Art der Orogenese, der Art der Geosynklinalen und der Ursache und der Art der Erstarrung, erscheint Suess als ein Vorgänger der Wegener-Argand-Schule, d. h. der Mobilisten, deren Gedankengänge er viel näher stand als dem der Kober-Stille-Schule. Obwohl Suess selbst bis zuletzt ein Fixist und Kontraktionist blieb, bereitete er eigentlich den Weg für die Mobilisten, wie er es früher auch für die Nappisten getan hatte.

Résumé Durant la première moitié du XXe siêcle, on peut distinguer deux principales écoles de pensée en tectonique globale, selon l'attitude de ses adhérents envers le principe de l'actualisme et selon leur croyance ou non à un ordre et une régularité intrinsèques en tectonique. Le premier groupe, ici appelé l'école de Wegener-Argand, suivit une voie actualiste et crût la Nature essentiellement irrégulière, de telle sorte qu'un traitement probabiliste fût considéré plus réaliste qu'un traitement déterministe. L'autre, appelé ici l'école de Kober-Stille, était essentiellement non-actualiste (néo-catastrophiste) et crût à une Nature ordonnée, régulière. Ces deux écoles correspondent aux mobilistes et aux fixistes d'Argand. Dans cet article, je montre que E. Suess, fût un actualiste convaincu, du moins en ce qui concerne ses opinions sur la tectonique globale, et qu'il rejetta toute notion de régularité dans les phénomènes tectoniques, autant spatiaux que temporaux. Dans ses interprétations des causes et de la nature de l'orogenèse, de la nature des géosynclinaux, et des causes et de la nature de la «stabilisation», Suess est un des précurseurs des «Wegener-Argandiens», c'est à dire des mobilistes. Bien qui'il fût demeuré, jusqu'à la fin de sa vie, fixiste et un avocat de la contraction, il semble que Suess ait préparé la voie aux mobilistes, de la mème façon qu'il l'avait fait pour les nappistes pendant le derier quart du XIXe siècle.

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Data for the post-Serravallian, ‘neotectonic’ evolution of the Pontides in northern Turkey indicate predominant ENE-WSW shortening with complementary NNW-SSE extension. We present a new fault plane solution for the Bartin earthquake (3 September 1968) and compare its mechanism with the movement picture of other neotectonic faults in the Pontides and northern Greece together with that of the Thessaloniki earthquake (20 May 1978). The general strain pattern exhibited by these structures agrees remarkably well with that inferred from early Tortonian-early Pleistocene structures reported from within the North Anatolian fault zone, which have been interpreted as indicating a possible reversal of the sense of movement along the North Anatolian transform fault. Here, we argue that such ‘incompatible’ structures may be related to the overall E-W shortening of Anatolia and the southern parts of the Black Sea resulting from the sideways continental escape from around the African and the Arabian promontories, rather than to hypothetical reversal of motion along the North Anatolian fault, for which there is no evidence other than the above-mentioned ‘incompatible’ structures. This new model also has important implications for seismicity and earthquake risk in regions contained within the southern part of the Black Sea plate.  相似文献   
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Abstract

A simplified method has been developed for solving leaky aquifer non-Darcian flow hydraulics. The principle of volumetric approach is combined with the confined-aquifer, time-dependent drawdown equation in an observation well. The groundwater flow in the leaky aquifer is assumed to obey a non-Darcian flow law of exponential type. The results are obtained in the form of type-curve expressions from which the necessary bundles of curves are drawn for a set of selective non-Darcian flow aquifer parameters. Although application of the methodology appears as rather limited but it provides a scientific contribution and extension of leaky aquifer theory towards nonlinear flow conditions. The methodology developed herein is applied to some actual field data from the eastern sedimentary basin in the Kingdom of Saudi Arabia.  相似文献   
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Outlier trimming and homogeneity checking/correction were performed on the monthly precipitation time series of various lengths from 267 stations in Turkey. Outlier values are usually found during dry summer months, and are concentrated mostly over the southern parts of the country, where the dry period is most pronounced, implying natural extremes rather than wrong measurements. Homogeneity analysis was done using the Standard Normal Homogeneity Test, on an individual monthly basis, which led to many non‐testable series due to lack of reference stations, especially during summer months. Yet, remaining testable months were usually helpful for the assessment of homogenity, revealing a well distributed set of stations that proved to be homogeneous. There were still a number of stations which either could not be tested efficiently, or were classified as inhomogeneous. Lack of metadata is argued to be largely responsible for inefficient homogeneity testing. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
10.
Zekai Şen  Essam Wagdani 《水文研究》2008,22(12):1788-1795
In arid‐region wadis, groundwater storage lies within shallow Quaternary alluvium deposits, which are connected with the present‐day hydrological cycle and, therefore, are replenished due to occasional runoff and flash flood occurrences. The groundwater resources are precious in these environments; therefore, their potentiality must be assessed with care in the best manner. The aquifer potentiality is calculated after the storativity and transmissivity parameter estimations, which require rather long‐duration field tests with restrictive assumptions in the theoretical model developments, such as the homogeneity and isotropy. It is the main purpose of this paper to expose the fundamentals of the slope‐matching procedure (SMP) and its application for short‐duration field tests in arid‐region aquifers. In this manner, the subsurface hydrogeological behaviours of the bored land pieces at and around the well locations are prospected in a detailed and refined manner. It is shown that in many cases the classical techniques are appropriate, inconvenient and inapplicable with conclusive reliable results and conclusions. The application of the SMP is presented for some aquifer tests from the central western part of the Kingdom of Saudi Arabia. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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