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21.
Bulent Bayram Dursun Zafer Seker Akhtar Jamil Hatice Catal Reis Nusret Demir Salih Bozkurt Abdulkadir Ince Turgay Kucuk 《Arabian Journal of Geosciences》2018,11(12):319
Obtaining information about tree species distribution in agricultural lands is a topic of interest for various applications, such as tree inventory, forest management, agricultural land management, crop estimation, etc. This information can be derived from images obtained from modern remote sensing technology, which is the most economical way as compare to field surveys covering large geographic areas. Therefore, in this study, a new method is proposed for extraction and counting of sparse and regular distributed individual pistachio trees from agricultural areas on large scale from high-resolution digital ortho-photo maps, which were obtained using an airborne sensor (Ultracam-X). The input images were first smoothed by applying Gaussian filter to reduce the impact of noise. Normalized difference vegetation indices (NDVI) were then derived to obtain vegetation areas followed by Otsu’s global thresholding algorithm to obtain candidate tree areas. Further, connected component (CC) analysis was applied to segregate each object. Morphological processing was performed to fill holes within tree objects and get smooth contours, which were obtained by using the Moore-neighbor tracing method (MNTM) for each CC, while geometrical constraints were applied to undermine possible non-tree elements from output image. To further improve the segmentation results for sparse trees, a new method was applied, called quadratic local analysis (QLA). QLA helped to segment the trees, which were missed by the Otsu method due to low contrast and resulted in improved accuracy (3–6%). The obtained results were compared with well-known support vector machine (SVM) classifier. Proposed method produced slightly better results (1–5%) than SVM for extraction of pistachio trees and obtained accuracy for QLA and SVM were 96 and 91% for region 1, while 91 and 90% for region 2 respectively. 相似文献
22.
H. Gürsoy O. Tatar J.D.A. Piper F. Kobulut Zafer Akp&#x;nar Baochun Huang A.P. Roberts B.L. Mesci 《Journal of Geodynamics》2011,51(5):308-326
The Anatolian accretionary collage between Afro-Arabia and Eurasia is currently subject to two tectonic regimes. Ongoing slip of Arabia relative to Africa along the Dead Sea Fault Zone in the east is extruding crustal blocks away from the indenter by a combination of strike-slip and rotation. This zone of compression gives way to an extensional province in western Turkey, which also includes the eastern sector of Aegean Province. Although it is now well established that rotational deformation throughout Anatolia is distributed and differential, the sizes of the blocks involved are poorly understood. As a contribution towards evaluating this issue in central-east Turkey, we report palaeomagnetic study of the mid-Miocene Kepezda? and Yamada? volcanic complexes in central-south Anatolia (38–39.5°N, 37.5–39°E). A distributed sample through the Yamada? complex identifies eruption during an interval of multiple geomagnetic field reversals (40 normal, 36 reversed, 8 intermediate sites) with a selected mean defined by 63 sites of D/I = 335.4/51.1° (α95 = 4.4°). The smaller Kepezda? complex (8 reversed, 4 normal and 1 intermediate site) yields a comparable mean direction from 12 sites of 338.7/49.8° (α95 = 14.1°). In the context of a range of radiometric age evidence, two thick normal polarity zones within the Yamada? succession probably correlate with zones C5ACn and C5ADn of the Geomagnetic Polarity Time Scale and imply that the bulk of the volcanic activity took place between ∼15 and 13.5 Ma. Comparison of the palaeomagnetic results with the adjoining major plate indenters shows that the Yamada? complex has rotated CCW by 29.3 ± 5.2° relative to Eurasia; the much smaller dataset from the Kepezda? complex indicates a comparable CCW rotation of 26.0 ± 11.8° with respect to Eurasia. The Arabian Indenter has also been rotating CCW since mid Miocene times, and the block incorporating these two volcanic complexes north of the East Anatolian Fault Zone (EAFZ) is determined to have rotated 18.2 ± 6.0° CCW relative to the northern perimeter of Arabia. Comparison with data to the north identifies quasi-uniform rotation across a ∼200 km wide block extending from the Central Anatolian Fault Zone in the northwest to close to the East Anatolian transform fault zone in the south east. Although absence of suitable younger rocks does not permit the timing of this rotation to be determined in the study area, analogies with results from the Sivas Basin suggest that it is young, and followed establishment of the major transform faults. Rotation has evidently taken place around bounding arcuate faults and accompanied westward expulsion as the accretionary collage north of Arabia has been subject to ongoing post-collisional indentation. 相似文献
23.
The present study is about the analysis of mean maximum and mean minimum temperatures carried out on annual, seasonal, and monthly timescales examining the data from 15 meteorological stations in Bangladesh for the period 1961–2008. Various spatial and statistical tools were used to display and analyze trends in temperature data. ArcGIS was used to produce the spatially distributed temperature data by using Thiessen polygon method. The nonparametric Mann–Kendall test was used to determine whether there is a positive or negative trend in data with their statistical significance. Sen’s method was also used to determine the magnitude of the trends. The results reveal positive trends in annual mean and mean maximum temperatures with 95 % significance. Trend test reveals that the significant positive trend is found in June to November in case of mean maximum temperature, but according to the mean minimum temperature, the situation is different and a significant positive trend was found from November to February. The analysis of the whole record reveals a tendency toward warmer years, with significantly warmer summer periods and slightly colder winters. These warming patterns may have important impacts on energy consumption, water supply, human health, and natural environment in Bangladesh. 相似文献
24.
Gündüz Horasan Aysun Boztepe Güney Ayşegül Küsmezer Feyza Bekler Zafer Öğütçü Nebiye Musaoğlu 《Journal of Asian Earth Sciences》2009,34(1):90-99
Scientists have proposed two fault systems of different ages in the Sea of Marmara: the Thrace-Eski?ehir Fault Zone of Early Miocene–Early Pliocene age and the North Anatolian Fault Zone of Late Pliocene–Recent age. Different seismicity rates and extensions of these faults onto land near ?stanbul have been suggested. One of the reasons for these differences is the contamination of seismicity catalogs by seismic events from quarries operated in ?stanbul and its vicinity, including Gaziosmanpa?a (Cebeci and Kemerburgaz), Çatalca, Ömerli, Gebze, and Hereke.In this study, we investigated waveforms of 179 seismic events (1.8 < Md < 3.0) from the KOERI, NEMC digital database. We determined differences between earthquakes and quarry blasts based on time- and frequency-domain analyses of their seismograms (amplitude peak ratio, power ratio, and spectral amplitude ratio) and used these differences as discriminants. The results of this study indicate that 15% and 85% of the investigated seismic events are earthquakes and quarry blasts, respectively. 相似文献
25.
John Lindeman Dave Broutman Stephen D. Eckermann Jun Ma Zafer Boybeyi 《Meteorology and Atmospheric Physics》2010,108(3-4):71-81
Mesoscale model simulations of representative trade winds impinging upon the Big Island of Hawaii are diagnosed for their mountain-wave characteristics by coupling a mesoscale model to a Fourier method. Localized phase-averaged wave momentum fluxes are calculated, which facilitates the study of wave generation from fine-scale topographic features. We find that the wave momentum fluxes are dominated by forcing from subsidiary topographic peaks, with the broader island topography controlling flow splitting and lee vortex generation. Waves also arise at the far northern and southern extremities of the island by acceleration of split flow. The strength of the local momentum fluxes proves to be sensitive to a small change in the incident flow direction. Areally integrated fluxes (wave drag) align closely with the incident flow direction and are an order of magnitude smaller than linear predictions and an order of magnitude larger than corresponding dividing streamline predictions. We briefly discuss the relevance of these results to the parameterization of subgrid-scale mountain-wave drag in climate and weather models. 相似文献
26.
Şahset İrdemez Nazmi Topçu Yalçın Şevki Yıldız Nuhi Demircioğlu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,21(2):175-181
In this study, the removal of nitrate ions from aqueous solutions with liquid membrane technique has been investigated for different organic solvent types in which solubilized tetradecyl trimethyl ammonium bromide (TDTMABr) as carrier. n-butyl alcohol, chloroform, and mixture of chloroform + n-hexane (n-hexane 85% + chloroform 15%) were used as organic solvent. Kinetic parameters (k
1d, k
2m, k
2a, t
max, R
mmax, J
mmax, J
amax) were calculated from obtained data. time R
a values of mixture, butyl alcohol, and chloroform are 0.81, 0.78, and 0.55, respectively. Similarly R
d, R
m, and t
max values of the mixture equal to 0.14, 0.04, and 87.92 min, respectively. This behavior of the system shows the organic solvent type is an effective parameter on separation yield. It can be concluded that the mixture is the most effective organic solvent type among the investigated ones, because liquid membrane systems should be operated within the range of having the R
m, R
d, and t
max values are minimum while R
a values are maximum. 相似文献
27.
Zafer Boybeyi Elena Novakovskaia Rosalyn MacCracken David P. Bacon Michael L. Kaplan 《Pure and Applied Geophysics》2007,164(10):2083-2100
This study performs a set of Observing System Simulation Experiments (OSSEs) using Geostationary Operational Environmental
Satellite (GOES) soundings. The primary objective of the OSSEs is to demonstrate that targeted observations can improve forecast
accuracy by enhancing the initial conditions and mitigating their uncertainties. Hurricane Floyd (1999) is chosen as a study
case. The main reason for choosing hurricane Floyd as a test case is that the movement of the storm was dictated by a mid-level
complex polar jet steering flow region. This well-defined feature allowed us to examine the inaccuracy of analysis over the
steering flow area using GOES soundings as targeted observations and its impact on the forecast track error. The set of experiments
starts from a baseline forecast of hurricane Floyd using the Operational Multiscale Environment model with Grid Adaptivity
(OMEGA). From GOES satellite soundings, atmospheric vertical profiles were extracted to simulate targeted observations. These
data extracts were assimilated in the initial conditions to simulate new forecasts of hurricane Floyd which were then compared
against both the baseline track and observed track. It was found that targeted observations in a forecast sensitive area can
help to reduce hurricane forecast track error. Assimilation of only the subset of data (about 50 soundings) from the subjectively
chosen fully sampled target region produced a considerable reduction of the track forecast errors (about 30%) within the first
critical three days of the forecast. 相似文献
28.
This paper discusses the preliminary results of a study on the vegetation pattern and its relationship with meteorological parameters in and around Istanbul. The study covers an area of over 6800 km2 consisting of urban and suburban centers, and uses the visible and near-infrared bands of Landsat. The spatial variation of the Normalized Difference Vegetation Index (NDVI) and meteorological parameters such as sensible heat flux, momentum flux, relative humidity, moist static energy, rainfall rate and temperature have been investigated based on observations in ten stations in the European (Thracian) and Anatolian parts of Istanbul. NDVI values have been evaluated from the Landsat data for a single day, viz. 24 October 1986, using ERDAS in ten different classes. The simultaneous spatial variations of sensible heat and momentum fluxes have been computed from the wind and temperature profiles using the Monin-Obukhov similarity theory. The static energy variations are based on the surface meteorological observations. There is very good correlation between NDVI and rainfall rate. Good correlation also exists between: NDVI and relative humidity; NDVI, sensible heat flux and relative humidity; NDVI, momentum flux and emissivity; and NDVI, sensible heat flux and emissivity. The study suggests that the momentum flux has only marginal impact on NDVI. Due to rapid urbanization, the coastal belt is characterized by reduced NDVI compared to the interior areas, suggesting that thermodynamic discontinuities considerably influence the vegetation pattern. This study is useful for the investigation of small-scale circulation models, especially in urban and suburban areas where differential heating leads to the formation of heat islands. In the long run, such studies on a global scale are vital to gain accurate, timely information on the distribution of vegetation on the earth’s surface. This may lead to an understanding of how changes in land cover affect phenomena as diverse as the atmospheric CO2 concentrations, the hydrological cycle and the energy balance at the surface-atmosphere interface. 相似文献
29.
Yasemin Oztekin Zafer Yazicigil Tolga Duran Hakan Dumrul Ersin Guler Ozcan Kocyigit 《洁净——土壤、空气、水》2010,38(10):921-926
In this study, electrochemical experiments were performed in non‐aqueous media in order to determine electrochemical behavior of some of the glyoxime derivatives (GDs). Phenylglyoxime (PG), p‐chloro‐phenylglyoxime (p‐CPG), and 1,2‐phenylendiamino‐p‐chlorophenylglyoxime (PACPG) were chosen as GDs. Pt wire, Ag/Ag+ (in 0.01 M AgNO3) and glassy carbon (GC) electrode were used as counter, reference, and working electrode, respectively. The multiscan cyclic voltammograms (CVs) of these compounds were registered in acetonitrile (MeCN) containing 0.1 M tetrabutylammonium tetrafluoroborat (TBATFB) at scan rate of 100 mV/s. The potential was swept from 0 to +2.0 V versus Ag/Ag+ (0.01 M). The CVs of GDs were compared with each other and the electrochemical behaviors of the compounds were investigated depending on the functional groups in their structures. The electrochemical characterization of these modified surfaces was performed and characterizations were compared with the chatacterization results of bare GC surfaces. The application areas for new surfaces were investigated. These results will be active in the disciplines of electrochemistry and industrial physical chemistry, and in related industrial fields at the dissemination of new information for scientific area. 相似文献
30.
Doğan Kalafat Kıvanç Kekovalı Feyza Akkoyunlu Zafer Ögütçü 《Journal of Seismology》2014,18(3):371-384
On 23 October 2011 at 1341 local time, a strong earthquake (Mw?=?7.1) occurred east of Lake Van (KOERI; Kandilli Observatory and Earthquake Research Institute). The focal parameters of the main shock and 29 aftershocks with M?≥?4.0 were obtained from regional broadband seismic data from KOERI network by using Regional Moment Tensor Inversion Code (Dreger 2002). It is confirmed that the main shock had thrust faulting mechanism. The stress tensor analysis was completed using the focal mechanism solutions and the software developed by (Gephart Comp Geosci 16: 953-989, 1990). The maximum principal stress (P compressional) of the main shock is aligned in a N-S (NNW/SSE) direction and the tensional axis (T dilatation) is aligned in an E-W (ENE-WSW) direction. The b value is calculated as 0.96 using the maximum likelihood method (Utsu 1999). 相似文献