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1.
Landslide susceptibility mapping for a landslide-prone area (Findikli,NE of Turkey) by likelihood-frequency ratio and weighted linear combination models 总被引：17，自引：0，他引：17
Landslides are very common natural problems in the Black Sea Region of Turkey due to the steep topography, improper use of
land cover and adverse climatic conditions for landslides. In the western part of region, many studies have been carried out
especially in the last decade for landslide susceptibility mapping using different evaluation methods such as deterministic
approach, landslide distribution, qualitative, statistical and distribution-free analyses. The purpose of this study is to
produce landslide susceptibility maps of a landslide-prone area (Findikli district, Rize) located at the eastern part of the
Black Sea Region of Turkey by likelihood frequency ratio (LRM) model and weighted linear combination (WLC) model and to compare
the results obtained. For this purpose, landslide inventory map of the area were prepared for the years of 1983 and 1995 by
detailed field surveys and aerial-photography studies. Slope angle, slope aspect, lithology, distance from drainage lines,
distance from roads and the land-cover of the study area are considered as the landslide-conditioning parameters. The differences
between the susceptibility maps derived by the LRM and the WLC models are relatively minor when broad-based classifications
are taken into account. However, the WLC map showed more details but the other map produced by LRM model produced weak results.
The reason for this result is considered to be the fact that the majority of pixels in the LRM map have high values than the
WLC-derived susceptibility map. In order to validate the two susceptibility maps, both of them were compared with the landslide
inventory map. Although the landslides do not exist in the very high susceptibility class of the both maps, 79% of the landslides
fall into the high and very high susceptibility zones of the WLC map while this is 49% for the LRM map. This shows that the
WLC model exhibited higher performance than the LRM model. 相似文献
2.
From the empirical energy literature, it is observed that studies focusing on the energy-economic growth nexus ignore the possible existence of gradual breaks as they employ methods without or with sharp structural breaks. Therefore, one can argue that they may yield biased and inefficient output in the presence of gradual breaks. The goal of this paper is to investigate the impact of solar energy consumption on GDP utilizing quarterly data over the period 1984–2018 for the USA. For this purpose, the paper performs a unit root test and a cointegration test that are based on the Fourier approximation to take gradual breaks into account. The paper also performs the dynamic ordinary least squares estimator to estimate long-run parameters. The findings document that there exists cointegration in the empirical model and that GDP is positively associated with solar energy consumption. Some implications based on the empirical findings are presented in the paper.
相似文献3.
Volkan Numan Bulut Mehmet Tufekci Celal Duran Mustafa Soylak Halit Kantekin 《洁净——土壤、空气、水》2010,38(7):678-683
A selective and sensitive method for the preconcentration, separation, and determination of palladium with flame atomic absorption spectrometry using 4,15‐bis[(4‐methylphenyl)sulfonyl]‐20,21‐dinitro‐2,3,4,5,6,7,9,10,12,13,14,15,16,17‐tetradecahydro‐8,11‐ethano‐1,18,4,8,11,15‐benzodioxa tetraaza cycloicosine (TNACIN) on XAD‐2010 was developed. TNACIN–Pd(II) complex formed acidic aqueous solution (0.075–0.100 M HNO3) was accumulated on XAD‐2010 and then eluted with 1 M HCl in acetone. The effects of some analytical parameters including pH, TNACIN amount, sample volume, eluent type, and concentration, sample flow rate and matrix ions were studied for optimization of the method. Detection limit and precision were calculated for Pd(II). This method was also verified with CRM and internal standard, and satisfactory results were obtained. 相似文献
4.
5.
In the present study,the effects of season on fatty acid composition,total lipids,and ω3/ω6ratios of northern pike muscle lipids in Kizilirmak River(Kirikkale,Turkey) were investigated.A total of 35 different fatty acids were determined in gas chromatography.Among these,palmitic,oleic,and palmitoleic acids had the highest proportion.The main polyunsaturated fatty acids(PUFAs) were found to be docosahexaenoic acid,eicosapentaenoic acid,and arachidonic acid.There were more PUFAs than monounsaturated fatty acids(MUFA) in all seasons.Similarly,the percentages of ω3 fatty acids were higher than those of total ω6 fatty acids in the fatty acid composition.ω3/ω6 ratios were calculated as 1.53,1.32,1.97,and 1.71 in spring,summer,autumn and winter,respectively.Overall,we found that the fatty acid composition and ω3/ω6 fatty acid ratio in the muscle of northern pike were significantly influenced by season. 相似文献
6.
As is known, the permeability coefficient of saturated and unsaturated rock masses can be found using the Bureau of Reclamation Method, which uses single and double packer water-pressure test results obtained from drillholes. The Bureau of Reclamation Method is, however, a time-consuming processes.
In this study, a new graphical method that does not necessitate the procedures mentioned above is proposed for the determination of the coefficient of permeability. This graphical method has been prepared with the idea that the amount of water injected into the testing section increases as the permeability of the rock mass increases. If the amount of average water loss in a 2-m test section is known, the average permeability coefficient of this section can be found using the proposed graphical method. 相似文献
7.
Landslide susceptibility mapping using GIS and digital photogrammetric techniques: a case study from Ardesen (NE-Turkey) 总被引：3，自引：3，他引：3
Ardesen is a settlement area which has been significantly damaged by frequent landslides which are caused by severe rainfalls
and result in many casualties. In this study a landslide susceptibility map of Ardesen was prepared using the Analytical Hierarchy
Process (AHP) with the help of Geographical Information Systems (GIS) and Digital Photogrametry Techniques (DPT). A landslide
inventory, lithology–weathering, slope, aspect, land cover, shear strength, distance to the river, stream density and distance
to the road thematics data layers were used to create the map. These layer maps are produced using field, laboratory and office
studies, and by the use of GIS and DPT. The landslide inventory map is also required to determine the relationship between
these maps and landslides using DPT. In the study field in the Hemsindere Formation there are units that have different weathering
classes, and this significantly affects the shear strength of the soil. In this study, shear strength values are calculated
in great detail with field and laboratory studies and an additional layer is evaluated with the help of the stability studies
used to produce the landslide susceptibility map. Finally, an overlay analysis is carried out by evaluating the layers obtained
according to their weight, and the landslide susceptibility map is produced. The study area was classified into five classes
of relative landslide susceptibility, namely, very low, low, moderate, high, and very high. Based on this analysis, the area
and percentage distribution of landslide susceptibility degrees were calculated and it was found that 28% of the region is
under the threat of landslides. Furthermore, the landslide susceptibility map and the landslide inventory map were compared
to determine whether the models produced are compatible with the real situation resulting in compatibility rate of 84%. The
total numbers of dwellings in the study area were determined one by one using aerial photos and it was found that 30% of the
houses, with a total occupancy of approximately 2,300 people, have a high or very high risk of being affected by landslides. 相似文献
8.
Duygu Ozdes Celal Duran Hacer Bayrak Volkan Numan Bulut Mehmet Tufekcı 《洁净——土壤、空气、水》2012,40(2):211-217
A new separation and preconcentration technique based on coprecipitation of Cu(II) and Ni(II) ions by the aid of Mo(VI)/di‐tert‐butyl{methylenebis[5‐(chlorobenzyl)‐4H‐1,2,4‐triazol‐3,4‐diyl]}biscarbamate (BUMECTAC) precipitate has been established. The Mo(VI)/BUMECTAC precipitate was dissolved by concentrated HNO3 and the solution was completed to 5.0 mL with distilled/deionized water. The levels of the analyte ions were determined by flame atomic absorption spectrometer. The effects of experimental conditions like HNO3 concentration, amount of BUMECTAC and Mo(VI), sample volume, etc. and also the influences of some foreign ions were investigated in detail on the quantitative recoveries of analyte ions. The preconcentration factors were found to be 40 for Cu(II) and 100 for Ni(II) ions. The detection limits for Cu(II) and Ni(II) ions based on 3σ (N:10) were 0.43 and 0.70 µg L?1, respectively. The relative standard deviations were found to be lower than 4.0% for both analyte ions. The accuracy of the method was checked by spiked/recovery tests and the analysis of two certified reference materials (Environment Canada TM‐25.3 and CRM‐SA‐C Sandy Soil C). The procedure was successfully applied to sea water and stream water as liquid samples and baby food as solid sample in order to determine the levels of Cu(II) and Ni(II) ions. 相似文献
9.
Adem Bayram Hızır Önsoy M. İhsan Kömürcü V. Numan Bulut 《Environmental Earth Sciences》2012,65(3):713-723
This paper evaluates the effects of Torul dam on the stream Harşit water quality in terms of 13 physico-chemical parameters
in the Gümüşhane Province, Eastern Black Sea Basin, Turkey. For this purpose, a study was fortnightly conducted during the
four seasons between March 2009 and February 2010. In two monitoring stations selected in the upstream and downstream of the
Torul dam, T, pH, DO and EC were determined in situ, and collected water samples were analyzed for TH, COD, NH4
+-N, NO2
−-N, NO3
−-N, TN, TKN, PO4
3−-P and MBAS. According to the Turkish Water Pollution Control Regulation (TWPCR), the stream Harşit was classified, and the
obtained results were evaluated for the values proposed by Turkish Standard (TS) 266 and World Health Organization (WHO) guidelines.
The results showed that the stream Harşit has high-quality water in terms of, T, pH, DO, COD, NH4
+-N and NO3
−-N, but slightly polluted water in terms of NO2
−-N, TKN and PO4
3−-P, and polluted for MBAS. It was concluded that Torul dam has a positive effect on the stream water quality in terms of decrease
in the annual average concentration values. The percent decreases for TH, COD, NH4
+-N, NO2
−-N, NO3
−-N, TN, TKN, PO4
3−-P and MBAS were 17.1, 20.3, 56.2, 62.6, 11.7, 11.9, 11.4, 17.8 and 71.4, respectively. The reason for these decreases is
probably due to the Torul dam reservoir where the water has a hydraulic residence time and the exposure to chemicals by aquatic
organisms or populations that ingest the water. Also, statistical analysis shows that there are significant correlations among
the studied parameters. 相似文献
10.
İ. Bulut 《New Astronomy》2009,14(7):604-606
The apsidal motion analysis of the eccentric eclipsing binaries: V397 Cep, V493 Car and BW Aqr have been presented. The method described by Lacy (1992) [Lacy, C.H S., 1992. AJ 104, 2213] has been used for the apsidal motion analysis. The apsidal motion periods have been found to be 174.2 ± 1.4, 277.3 ± 21.3 and 7195 ± 174 years for V397 Cep, V493 Car and BW Aqr, respectively. 相似文献