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1.
Curie-point depth map of Turkey 总被引：3，自引：0，他引：3
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Turkey currently lacks a fully functional flood forecasting system (FFS). However, the studies necessary for establishing such a system are still being performed by the Turkish State Meteorological Service. The main purpose of this study was to determine the technical architecture of the FFS intended to be developed in Turkey and to design a flood forecasting and inundation-mapping system integrated with spatial data infrastructure (SDI). Because SDIs provide interoperability among the institutions by enabling collective use of data and services, this enables decision makers to take correct and rapid decisions regarding the forecasting. In the design of the system, the Web services architecture presented by the open geospatial consortium that develops international standards for SDI realizations was taken as a basis. Designed with flexibility and an expandable architecture, the system will enable instant access to up-to-date data from different institutions through Web services and meets the requirements of a real-time FFS. While the criteria requiring the expansion of the designed system were explained, its implementation was left for future studies. 相似文献
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This paper's primary purpose is to compare the 2D and 3D analysis methodologies in investigating the performance of a concrete faced rock‐fill dams under dynamic loading conditions. The state of stress on the face plate was obtained in both cases using a total strain based crack model to predict the spreading of cracks on the plate and the corresponding crack widths. Results of the 2D and 3D analyses agree well. Although significantly more demanding, 3D analyses have the advantage of predicting the following: (i) the opening of the vertical construction joints; (ii) the cracking at the valley sides; and (iii) the crushing of the plate during the seismic action. During the earthquake loading, the cracking predicted at the base of the face plate after the impounding spread significantly towards the crest of the dam; however, the crack widths are obtained relatively small. Crushing of the face plates at the construction joints is the primary cause of the large scale cracking predicted on the face plate for high intensity earthquakes. Earthquake induced permanent deformation of the fill increases the compressive stresses on the face plate, thereby reducing the minute cracking on the plate. However, this effect also leads to significant increases in the residual openings at the construction joints and at the plinth level. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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The effect of welding degree on geotechnical properties of an ignimbrite flow unit: the Bitlis castle case (eastern Turkey) 总被引：1，自引：0，他引：1
Tamer Koralay Mehmet ?zkul Halil Kumsar Sefer Beran ?elik Kadir Pekta? 《Environmental Earth Sciences》2011,64(3):869-881
Ignimbrites are associated with nearly most of the world’s volcanoes and are defined as a deposit from pyroclastic density
currents. They consist predominantly of pumiceous lapilli and blocks, and glass shards, which shows evidence of having been
emplaced as a concentrated hot and dry particulate flow. These rocks are widely used as building stone especially in ancient
buildings. Bitlis valley is covered by ignimbritic products, derived from Nemrut stratovolcano, one of the significant volcanic
centers in Eastern Anatolia. The Bitlis ignimbrite is separated into lower level (LL), middle level (ML) and upper level (UL)
according to color, welding degree and structural features. All three levels were used extensively in many parts of the Bitlis
castle as masonry materials. Studies were carried out on mineralogical and geochemical composition and on physical and mechanical
properties of the ignimbrites. In addition, a freeze–thaw cycle test was executed. There are no considerable differences in
mineralogical composition among the levels of ignimbrite. All levels contain plagioclase, sanidine, pyroxene, and opaque mineral.
In addition, anorthoclase and quartz are seen. In general, the LL of ignimbrite shows relic perlitic and eutaxitic texture,
whereas eutaxitic and vesicular texture are commonly developed in the ML and UL, respectively. Lower, middle, and upper level
ignimbrite samples display similar and limited compositional spread in terms of major oxide elements. They have trachyte composition.
Building stones can be classified according to mineralogy, mechanical and physical properties and processing types. Mechanical
and physical properties are very important with respect to stone quality/durability. The mechanical and physical properties
of the ignimbrites are controlled by the welding degree. It was found that increasing welding degree from UL to LL correlates
with increasing density, compressive strength and slake durability index and with decreasing porosity. The Bitlis ignimbrites
have turned out as susceptible to freeze–thaw cycles. 相似文献
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Adem Dogangun Ramazan Acar Halil Sezen Ramazan Livaoglu 《Bulletin of Earthquake Engineering》2008,6(3):505-517
Almost all historical minarets in Turkey were constructed using cut stone, masonry blocks or combination of these two materials.
The structural and geometrical properties of each masonry minaret, or slender tower structure, depend on many factors including
the structural knowledge and applications at the time of construction, experience of the architect or engineer, seismicity
of the region, and availability of construction materials in that area. Recent earthquakes in Turkey have shown that most
masonry minarets in high seismic regions are vulnerable to structural damage and collapse. In this study, in order to investigate
the dynamic behavior of historical unreinforced masonry minarets, three representative minarets with 20, 25, and 30 m height
were modeled and analyzed using two ground motions recorded during the 1999 Kocaeli and Duzce, Turkey earthquakes. The modal
analyses of the models have shown that the structural periods and the overall structural response are influenced by the minaret
height and spectral characteristics of the input motion. The dynamic displacement and axial stress time histories are computed
at the critical points on the minarets. During recent earthquakes, most minaret failures occurred above the base of the structure.
Consistent with the observed response, the largest stresses were calculated at the same location. 相似文献
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A model of a first generation intermediate star of 5M
, with Z=0 has been considered. The model is at an advanced stage of its evolution and has a double shell burning. It burns helium in the inner shell, and hydrogen, via CNO cycle, in the outer shell.
=(log/log)
T
and
T
=(log/logT)
were computed allowing for the oscillations of the relative mass abundance of the reagents in nuclear reactions. Including
=(log/log)
T
and
=(log/logT)
of mean molecular weight and the effect of the oscillations of abundances due to nuclear reactions, stability was studied. Contrary to the results of the static calculations, we found that instability due to the excitation mechanism provided by the high temperature sensitivity of energy generation rate propagates up to the surface. Thus the model in question was found to be unstable against radial adiabatic pulsations, in its fundamental mode. 相似文献
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This paper presents the practical closed‐form solutions for elastic settlement under the linear full‐contact pressures on rectangular areas resting upon an elastic mass. The linear pressure distribution is mostly assumed in practice for the rectangular footing having biaxial bending. The equations presented here are determined by evaluating the integration of Steinbrenner's strain approximation based on the stress solutions from the Boussinesq equations. The presented formulae are validated to be used for the elastic settlement under any point of linear full‐contact loading, triangular and embankment types of pressure cases. In this respect, it represents a significant step forward in the understanding of elastic settlement and rotation under the practical loading cases. The presented solutions are concise and easy to use. The numerical examples are demonstrated and the resulting influence factors in graphical forms are presented for their practical use especially in the elastic settlement calculations of rectangular footing subjected to the biaxial bending. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
10.
Halil İbrahim Gülşen-Rothmund Özgür Avşar Ulaş Avşar Bedri Kurtuluş Evren Tunca 《Environmental Earth Sciences》2018,77(14):546
Elemental accumulation, distribution and relationship profiles for sediment samples taken at 81 localities in the Köyce?iz Lake were investigated. Spatial distribution maps for ten elements (Cu, Pb, Zn, Ni, Cr, Co, Mn, Mo, Al, Fe) were created using the ordinary kriging interpolation method. Statistical tests revealed that the sediments taken from areas close to the Namnam (NamSM) and Karg?cak (KarSM) stream mouths have the highest element content. In addition, sediments close to NamSM have the highest contamination, according to contamination degree and modified contamination degree values. On the other hand, sediments close to KarSM have the highest value on the pollution load index. The enrichment factor and contamination factor values of Cr and Co, and especially Ni, close to NamSM are striking and have significantly higher values compared to the rest of the lake. There are strong correlations between these three elements, which were also confirmed by cluster analysis. Ni is the element having the highest value on the geoaccumulation index. In addition, according to the toxic unit results, it was found that 84–89% of the element-based toxic effect in the lake is due to Ni alone. According to the mean effect range median quotient values, the sediments of Köyce?iz Lake have a potential to show toxic effects of at least 76% in living organisms, which is due to the high levels of Ni. According to the mean probable effect low quotient value, it has been determined that Köyce?iz Lake is at a “highly impacted” level, which is the worst possible value on the quality scale. 相似文献