Foundation–structure systems over a rupturing normal fault: Part I. Observations after the Kocaeli 1999 earthquake     

Ioannis Anastasopoulos  George Gazetas 《Bulletin of Earthquake Engineering》2007,5(3):253-275

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Progressive Failure of Slopes: Stochastic Simulation Based on Transition Probabilities and Markov Chains     

Deliveris  Alexandros V.  Zevgolis  Ioannis E.  Koukouzas  Nikolaos C. 《Geotechnical and Geological Engineering》2021,39(6):4491-4510

Geotechnical and Geological Engineering - A reliability analysis framework for the stochastic simulation of slope progressive failure is proposed in the current work. Progressive failure is...  相似文献   

Mediterranean forest species mapping using classification of Hyperion imagery     

Georgia Galidaki  Ioannis Gitas 《国际地球制图》2015,30(1):48-61

Regional operational forest species mapping is an active research topic that aims to provide the systematic and updatable information necessary for understanding and monitoring the rapidly changing forest environment. In this study, we investigated the potential of satellite hyperspectral imagery in regional forest species mapping by employing a pixel-based and an object-based nearest neighbour classifier in two different Mediterranean study areas. The overall thematic accuracy of the produced maps was assessed using reference data collected in the field and ranged between 0.72 and 0.83. No approach was found to be superior for the study areas. The McNemar test showed no statistically significant difference at the 95% confidence level in the classification accuracies achieved by the two approaches. Both pixel- and object-based approaches provide useful maps, suggesting that regional forest species mapping from space has much potential.  相似文献   

How a sharp rostral dimorphism affects the life history,population structure and adaptability of a small shrimp: the case study of Hippolyte sapphica          下载免费PDF全文

Roman Liasko  Chryssa Anastasiadou  Alexandros Ntakis  Ioannis D. Leonardos 《Marine Ecology》2015,36(3):400-407

The rostrum shows a large variation across caridean shrimps; however, our knowledge about the biological significance of this morphological structure is very limited, and information on its genetic control is completely absent. The present study concentrates on an unusual rostral dimorphism in a population of small Mediterranean caridean shrimp and combines laboratory and field observations. Analysis of lab‐reared offspring supports the hypothesis that the post‐larval elongation of the rostrum is controlled by a single genetic locus, with the long dentate rostrum representing the recessive state and the short larval‐like rostrum representing the completely dominant state. The short rostrum is a sparsely distributed character; our results obtained from field studies suggest that it reduces the viability and probability of egg‐bearing among large females but, unexpectedly, the specimens with a short rostrum show consistently more rapid sex differentiation and a significantly higher propensity to become males. Therefore, it has to be concluded that, under certain conditions, a single emergent character could influence the species evolution in a rather complex manner, thus affecting the life history, population structure and dynamics and mortality in certain subgroups. In turn, the genetic factors responsible for the different phenotypes would tend to be segregated through different subpopulations and size classes, thus partially escaping the negative selective pressure.  相似文献   

Tracing tsunami signatures of the ad 551 and ad 1303 tsunamis at the Gulf of Kyparissia (Peloponnese,Greece) using direct push in situ sensing techniques combined with geophysical studies     

Lea Obrocki  Andreas Vött  Dennis Wilken  Peter Fischer  Timo Willershäuser  Benjamin Koster  Franziska Lang  Ioannis Papanikolaou  Wolfgang Rabbel  Klaus Reicherter 《Sedimentology》2020,67(3):1274-1308

The western Peloponnese was repeatedly hit by major tsunami impacts during historical times as reported by historical accounts and recorded in earthquake and tsunami catalogues. Geological signatures of past tsunami impacts have also been found in many coastal geological archives. During the past years, abundant geomorphological and sedimentary evidence of repeated Holocene tsunami landfall was found between Cape Katakolo and the city of Kyparissia. Moreover, neotectonic studies revealed strong crust uplift along regional faults with amounts of uplift between 13 m and 30 m since the mid-Holocene. This study focuses on the potential of direct push in situ sensing techniques to detect tsunami sediments along the Gulf of Kyparissia. Direct push measurements were conducted on the landward shores of the Kaiafa Lagoon and the former Mouria Lagoon from which sedimentary and microfaunal evidence for tsunami landfall are already known. Direct push methods helped to decipher in situ high-resolution stratigraphic records of allochthonous sand sheets that are used to document different kinds of sedimentological and geomorphological characteristics of high-energy inundation, such as abrupt increases in grain size, integration of muddy rip-up clasts and fining upward sequences which are representative of different tsunami inundation pulses. These investigations were completed by sediment coring as a base for local calibration of geophysical direct push parameters. Surface-based electrical resistivity tomography and seismic data with highly resolved vertical direct push datasets and sediment core data were all coupled in order to improve the quality of the geophysical models. Details of this methodological approach, new in palaeotsunami research, are presented and discussed, especially with respect to the question of how the obtained results may help to facilitate tracing tsunami signatures in the sedimentary record and deciphering geomorphological characteristics of past tsunami inundation. Using direct push techniques and based on sedimentary data, sedimentary signatures of two young tsunami impacts that hit the Kaiafa Lagoon were detected. Radiocarbon age control allowed the identification of these tsunami layers as candidates for the ad 551 and ad 1303 earthquake and tsunami events. For these events, there is reliable historical data on major damage on infrastructure in western Greece and on the Peloponnese. At the former Mouria Lagoon, corroborating tsunami traces were found; however, in this case it is difficult to decide whether these signatures were caused by the ad 551 or the ad 1303 event.  相似文献   

Incremental dynamic analysis of woodframe buildings     

Ioannis P. Christovasilis  Andre Filiatrault  Michael C. Constantinou  Assawin Wanitkorkul 《地震工程与结构动力学》2009,38(4):477-496

The collapse of wood buildings was one of the main contributors to the heavy death toll and economic losses during the 1995 Hyogo‐ken Nanbu (Kobe) earthquake in Japan. In California, half of the property loss from the 1994 Northridge earthquake was attributed to wood construction. Based on damage observed in recent earthquakes, the seismic vulnerability of existing wood buildings under maximum credible seismic events is uncertain. The main objective of this study is to quantify the seismic collapse fragilities and collapse mechanisms of a two‐story townhouse and three‐story woodframe apartment building through numerical analyses. Three construction quality variants (poor, typical and superior) were considered for each building in order to assess the effects of construction qualities on seismic collapse fragilities. The buildings were also re‐designed according to the 2006 edition of the International Building Code to quantify the seismic fragilities of modern woodframe construction. The results obtained suggest that the construction quality, excitation direction and wall finish materials can influence significantly the collapse fragilities of woodframe buildings. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

A significant aegean volcanic eruption during the second millennium B.C. revealed by thermoluminescence dating     

I. Liritzis  C. Michael  R. B. Galloway 《Geoarchaeology》1996,11(4):361-371

Thermoluminescence dating of four volcanic samples (material of eruption ejecta), from the island of Yiali near the Nissyros volcano in the southeastern Aegean sea, Greece, has revealed, for first time, a volcanic eruption which occurred during the 2nd millennium B.C. (c. 1460 B.C.), different from the known Santorini eruption. The interrelation between Yiali and the well-known Santorini eruption, as well as the implications of these eruptions regarding their potential impact to the Aegean prehistoric archaeology (demise of the Minoan civilization), are discussed. © 1996 John Wiley & Sons, Inc.  相似文献   

Effects of fish farm waste on Posidonia oceanica meadows: synthesis and provision of monitoring and management tools     

Holmer M  Argyrou M  Dalsgaard T  Danovaro R  Diaz-Almela E  Duarte CM  Frederiksen M  Grau A  Karakassis I  Marbà N  Mirto S  Pérez M  Pusceddu A  Tsapakis M 《Marine pollution bulletin》2008,56(9):1618-1629

This paper provides a synthesis of the EU project MedVeg addressing the fate of nutrients released from fish farming in the Mediterranean with particular focus on the endemic seagrass Posidonia oceanica habitat. The objectives were to identify the main drivers of seagrass decline linked to fish farming and to provide sensitive indicators of environmental change, which can be used for monitoring purposes. The sedimentation of waste particles in the farm vicinities emerges as the main driver of benthic deterioration, such as accumulation of organic matter, sediment anoxia as well as seagrass decline. The effects of fish farming on P. oceanica meadows are diverse and complex and detected through various metrics and indicators. A safety distance of 400 m is suggested for management of P. oceanica near fish farms followed by establishment of permanent seagrass plots revisited annually for monitoring the health of the meadows.  相似文献   

An overview of geological originated materials as a trend for adsorption in wastewater treatment     

Yasmin Vieira  Matias Schadeck Netto  Éder C.Lima  Ioannis Anastopoulos  Marcos L.S.Oliveira  Guilherme L.Dotto 《地学前缘(英文版)》2022,(1):457-477

Adsorption is a unit operation widely used for the tertiary treatment of the most diverse effluents,whose mechanism is based on removing recalcitrant compounds from the organic and inorganic origin.In this process,choosing a suitable adsorbent is a fundamental point.This review article focuses on the adsorbents with natural geological origin:minerals,clays,geopolymers,and even wastes resulted from mining activity.Therefore,over 450 articles and research papers were explored.These materials’main sources are described,and their characteristics,composition,and intrinsic properties are related to adsorption.Herein,we discuss the effects of several process parameters,such as p H,temperature,pollutant,and adsorbent concentration.Furthermore,equilibrium,kinetics,and thermodynamic aspects are also addressed,and relevant regeneration prospects and final disposal.Finally,some suggestions and perspectives on applying these adsorbents in wastewater treatment are presented as future trends.  相似文献   

Optimization of the seismic response of bridges using variable-width joints     

Ioannis G. Mikes  Andreas J. Kappos 《地震工程与结构动力学》2023,52(1):111-127

An aspect of seismic design of bridges that has hardly received proper attention so far is the appropriate selection of joint gaps. End gaps define the boundary conditions of the bridge and affect its dynamic response; their proper design can lead to an improved structural performance under dynamic actions. The idea of the ‘Dynamic Intelligent Bridge’ is explored here, wherein current bridge joints that have a fixed width are substituted by variable-width joints and, under seismic loading, the joint gap is optimised either with a one-off adjustment, or continuously (in real time) through semi-active control. In all cases, a novel device is used that permits this improved behaviour of the joints, the moveable shear key (MSK), a device for blocking the movement of the bridge deck, which has the possibility to slide, hence varying the size of the existing joint gap. In this context, the effect of gap size on the seismic response of bridges is assessed herein and a methodology is put forward for optimising this size, using a number of criteria such as maintaining the functionality of the bridge for moderate earthquakes, and ensuring the safety of the bridge and its users under earthquakes stronger than that used for design.  相似文献