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In the present study, the analysis of the international landslide literature is aimed. The landslide is perhaps one of the
most complex natural phenomena. Also, due to landslides, a considerable amount of loss of lives and economic losses is encountered
throughout the world. Although a vast amount of landslide papers is published in international journals, a statistical assessment
on this literature is not encountered. For this reason, this study is performed. For the assessment of the international landslide
literature, the Science Citation Index Expanded (WOS; Web of Science) published by Institute of Scientific Information (now
Thomson Scientific), USA for the period 1945–2008, is considered. A total of 3,468 publications are found and this data is
stored into Oracle XE database and queried by using Structured Query Language and Procedural Language/Structured Query Language.
In the following stages, some statistical analyses are performed and the possible trends are discussed. 相似文献
145.
Daniela Plachá Helena Raclavská Dalibor Matýsek Mark H Rümmeli 《Geochemical transactions》2009,10(1):12-21
The polycyclic aromatic hydrocarbon (PAH) contamination of urban, agricultural and forest soil samples was investigated from
samples obtained in the surroundings of Valasske Mezirici. Valasske Mezirici is a town located in the north-east mountainous
part of the Czech Republic, where a coal tar refinery is situated. 16 PAHs listed in the US EPA were investigated. Organic
oxidizable carbon was also observed in the forest soils. The PAH concentrations ranged from 0.86-10.84 (with one anomalous
value of 35.14) and 7.66-79.39 mg/kg dm in the urban/agricultural and forest soils, respectively. While the PAH levels in
the urban/agricultural soils are within the range typically found in industrialized areas, the forest soils showed elevated
PAH concentrations compared to other forest soils in Western and Northern Europe. The PAH concentrations and their molecular
distribution ratios were studied as functions of the sample location and the meteorological history. The soils from localities
at higher altitudes above sea level have the highest PAH concentrations, and the PAH concentrations decrease with increasing
distance from the town. 相似文献
146.
François Bache Speranta‐Maria Popescu Marina Rabineau Christian Gorini Jean‐Pierre Suc Georges Clauzon Jean‐Louis Olivet Jean‐Loup Rubino Mihaela Carmen Melinte‐Dobrinescu Ferran Estrada Laurent Londeix Rolando Armijo Bertrand Meyer Laurent Jolivet Gwénaël Jouannic Estelle Leroux Daniel Aslanian Antonio Tadeu Dos Reis Ludovic Mocochain Nikola Dumurdžanov Ivan Zagorchev Vesna Lesić Dragana Tomić M. Namık Çağatay Jean‐Pierre Brun Dimitrios Sokoutis Istvan Csato Gülsen Ucarkus Ziyadin Çakır 《Basin Research》2012,24(2):125-153
The Messinian Salinity Crisis is well known to have resulted from a significant drop of the Mediterranean sea level. Considering both onshore and offshore observations, the subsequent reflooding is generally thought to have been very sudden. We present here offshore seismic evidence from the Gulf of Lions and re‐visited onshore data from Italy and Turkey that lead to a new concept of a two‐step reflooding of the Mediterranean Basin after the Messinian Salinity Crisis. The refilling was first moderate and relatively slow accompanied by transgressive ravinement, and later on very rapid, preserving the subaerial Messinian Erosional Surface. The amplitude of these two successive rises of sea level has been estimated at ≤500 m for the first rise and 600–900 m for the second rise. Evaporites from the central Mediterranean basins appear to have been deposited principally at the beginning of the first step of reflooding. After the second step, which preceeded the Zanclean Global Stratotype Section and Point, successive connections with the Paratethyan Dacic Basin, then the Adriatic foredeep, and finally the Euxinian Basin occurred, as a consequence of the continued global rise in sea level. A complex morphology with sills and sub‐basins led to diachronous events such as the so‐called ‘Lago Mare’.This study helps to distinguish events that were synchronous over the entire Mediterranean realm, such as the two‐step reflooding, from those that were more local and diachronous. In addition, the shoreline that marks the transition between these two steps of reflooding in the Provence Basin provides a remarkable palaeogeographical marker for subsidence studies. 相似文献
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Hot spot analysis based on network spatial weights to determine spatial statistics of traffic accidents in Rize,Turkey 总被引:1,自引:0,他引:1
H. Ebru Colak Tugba Memisoglu Y. Selcuk Erbas Sevket Bediroglu 《Arabian Journal of Geosciences》2018,11(7):151
The increased numbers of vehicles using roads in the world today are cause of traffic-related problems, and in this respect, road traffic accidents are an important topic relating to public health. Especially on the road connecting two border provinces, traffic accidents are increasing substantially in parallel with the quantity of transport facilities. By determining areas where traffic accidents result in deaths or injuries, accident prevention strategies can be developed. This study applies the spatial statistics techniques using Geographical Information Systems (GIS) to determine the intensity of traffic accidents (hot-spot regions) over 45 km of main routes in Rize Province, Turkey. Traffic accidents recorded in data spanning 5 years are combined with a geographical dataset for evaluation using hot spot statistical analysis. Unlike other studies, this study used hot spot analysis based on network spatial weights (an innovative review in the methods of determining traffic accident hot spots: “novel application of GIScience”) to identify black spots for traffic safety. To perform the analysis using Hot Spot Analysis: Getis-Ord Gi*, a generated network dataset and the spatial weights of the road data are used to generate network spatial weights. Then, Kernel Density method is used to define traffic accident black spots. Finally, these two methods are compared each other with visually. 相似文献
149.
In this study, various amounts of oxygen were added to the anaerobic phase of an anaerobic‐aerobic sequencing batch reactor (SBR) receiving azo dye remazol brilliant violet 5R to mimic the input of oxygen into the anaerobic zones of biological textile wastewater treatment plants. The effect of oxygen on the anaerobic biodegradative capability of the mixed microbial culture for remazol brilliant violet 5R was investigated. To investigate the effect of oxygen on anaerobic azo dye biodegradation, the anaerobic phase of the SBR cultures were exposed to a very low limited amount of oxygen for various air flow rates. Initially, an air flow rate of 20 mL/min was applied, further on the air flow rate in the anaerobic phase was increased up to 40 mL/min. System performance was determined by monitoring chemical oxygen demand, color removal rate, activities of anaerobic (azo reductase) and aerobic enzymes (catechol 2,3‐dioxygenase, catechol 1,2‐dioxygenase). The results of percentage COD reduction at each stage were similar for all runs, giving an overall reduction of 96%. Anaerobic color removal efficiency and azo reductase activity of anaerobic microorganisms were adversely affected by the addition of oxygen. Color removal efficiencies of the anaerobic phases decreased from 80% down to 42 and 38% for the limited oxygen conditions of 20 mL/min and 40 mL/min, respectively. It was observed that the activity of catechol 2,3‐dioxygenase and catechol 1,2‐dioxygenase, involved in breakage of aromatic rings, increased after they are exposed to oxygen limited conditions compared to fully anaerobic conditions. It was also observed that catechol 1,2‐dioxygenase enzyme activity increased by increasing the oxygen level on oxygen limited conditions in the anaerobic zone. 相似文献
150.
Nİhal Akyol Tevfİk Özgür Kurtulmuş Murat Çamyildiz Talİp Güngör 《Pure and Applied Geophysics》2013,170(12):2107-2125
Recordings of micro- and moderate-size local earthquakes have been used to quantify site effects in the central-west Turkey which contains one of the world’s best examples of a rapid intra-continental extension with its high population and industrial potential. We analyzed 436 earthquakes with local magnitudes ranging between 2.0 and 5.6 using three component digital recordings from 32 stations. Site functions were obtained using two different spectral ratio approaches (horizontal to vertical spectral ratio, HVSR, and standard spectral ratio, SSR). HVSR estimates of transverse and radial S-waves were compared with one another. Epicentral distance, magnitude and back-azimuth dependencies of site functions were also evaluated. In general, HVSR values from transverse and radial S-waves are similar within a factor of 2. The back-azimuth dependencies of transverse S-wave HVSR results are more significant than distance and magnitude dependencies. On the other hand, averaging of transverse and radial S-wave HVSR results eliminates systematic back-azimuth dependencies caused by source radiation effects. Distributions of HVSR estimates along ~N–S linear array, which traversed main grabens in the region with a station spacing of 3–4 km, reflect subsurface geological complexities in the region. The sites located near the basin edges are characterized by broader HVSR curves. Broad HVSR peaks could be attributed to the complexity of wave propagation related to significant 2D/3D velocity variations at the sediment–bedrock interface near the basin edges. The results also show that, even if the site is located on a horst, the presence of weathered zones along the surface could cause moderate frequency dependent site effects. Comparison of HVSR and SSR estimates for the stations on the graben sites showed that SSR estimates give larger values at lower frequencies which could be attributed to lateral variations in regional velocity and attenuation values caused by basin geometry and edge effects. 相似文献