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1.
Outlier trimming and homogeneity checking/correction were performed on the monthly precipitation time series of various lengths from 267 stations in Turkey. Outlier values are usually found during dry summer months, and are concentrated mostly over the southern parts of the country, where the dry period is most pronounced, implying natural extremes rather than wrong measurements. Homogeneity analysis was done using the Standard Normal Homogeneity Test, on an individual monthly basis, which led to many non‐testable series due to lack of reference stations, especially during summer months. Yet, remaining testable months were usually helpful for the assessment of homogenity, revealing a well distributed set of stations that proved to be homogeneous. There were still a number of stations which either could not be tested efficiently, or were classified as inhomogeneous. Lack of metadata is argued to be largely responsible for inefficient homogeneity testing. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
2.
The interaction between waves and artificial reefs (ARs; a hollow cube weighing 8.24 kN (0.84 t) and a water pipe weighing 1.27 kN (0.13 t)) in shallow waters was investigated with respect to variations in design weight, orientation (for cube; 45° and 90° angles, for pipe; 0°, 90°, and 180° angles to flow), depth (1–20 m), and bottom slope (10?1, 30?1, and 50?1). Physics equations and FLUENT software were used to estimate resisting and mobilising forces, and drag coefficients. Drag coefficients for the hollow cube were 0.76 and 0.85 at 45° and 90° angles to the current, respectively, and 0.97, 0.38, and 1.42 for the water pipe at 0°, 90°, and 180° angles to the current, respectively. Deepwater offshore wave conditions at six stations were transformed into shallow nearshore waters representative of the artificial reef site. Waters deeper than 12 and 16 m are safe to deploy blocks with angles of 45° and 90°, respectively. However, water pipes constructed at angles of 90° and 180° to the current were estimated as being unstable for 365 out of 720 cases at all stations (only one station was stable for all cases). Water pipes angled at 0° were found to be stable in all 360 cases. Slope had a significant effect on weight and depth. Results from this study provide an important reference for engineers performing projects aiming to increase the performance and service life of ARs. 相似文献
3.
Mehmet ?ahin B. Yi?it Y?ld?z Ozan ?enkal Vedat Pe?temalc? 《Journal of the Indian Society of Remote Sensing》2012,40(3):399-409
This study introduces artificial neural networks (ANNs) for the estimation of land surface temperature (LST) using meteorological and geographical data in Turkey (26?C45°E and 36?C42°N). A generalized regression neural network (GRNN) was used in the network. In order to train the neural network, meteorological and geographical data for the period from January 2002 to December 2002 for 10 stations (Adana, Afyon, Ankara, Eski?ehir, ?stanbul, ?zmir, Konya, Malatya, Rize, Sivas) spread over Turkey were used as training (six stations) and testing (four stations) data. Latitude, longitude, elevation and mean air temperature are used in the input layer of the network. Land surface temperature is the output. However, land surface temperature has been estimated as monthly mean by using NOAA-AVHRR satellite data in the thermal range over 10 stations in Turkey. The RMSE between the estimated and ground values for monthly mean with ANN temperature(LSTANN) and Becker and Li temperature(LSTB-L) method values have been found as 0.077?K and 0.091?K (training stations), 0.045?K and 0.003?K (testing stations), respectively. 相似文献
4.
Studies on anaerobic ammonium oxidation (ANAMMOX) have been increasing due to its advantages over traditional nitrification–denitrification systems. However, long and difficult start‐up periods of ANAMMOX reactors may sometimes be frustrating for researchers dealing with them first time in the lab. Therefore, a guide for starting up ANAMMOX reactors will greatly help them and enhance the use of this technology. Three trials, each has three reactors, have been carried out to reach successful start up in this study. An expected ANAMMOX enrichment could not be achieved in the first and second trials. Under the light of the experiences gained from the unsuccessful ones, the third trial resulted in >95% ammonium removals within 20–50 days. It is possible to startup or to enrich ANAMMOX reactors within 50 days by presented strategy guide. 相似文献
5.
Solar radiation and precipitable water modeling for Turkey using artificial neural networks 总被引：1，自引：0，他引：1
Ozan Şenkal 《Meteorology and Atmospheric Physics》2015,127(4):481-488
6.
Ozan Arslan 《Water Resources》2013,40(3):315-324
Incorporating spatial information data into the principal component analysis is of importance. Some proposed methods of spatial weighting schemes to be applied to the ordinary PCA are reviewed and a new version of the method is proposed in the context of spatial analysis for geospatial multivariate analysis. In view of spatial variations in the hydrochemistry of rivers such combined version of the technique might be useful for reliable estimates. 相似文献
7.
The submerged 3D turbulent jet flow behavior around a pile on a rigid bed and on a scoured bed was studied experimentally and numerically. ADV was used to obtain the jet velocity distributions and Realizable k–ε turbulence model was used for the prediction of flow field around a pile. The jet flow area was three-dimensional and thus numerical model was a three-dimensional model. The numerical results were used to predict the velocity close to the pile and bed shear stress on the bed. In general, the results indicated that the flow field was also in agreement with the findings of previous experiments in literature and the related principles in the subject area. The experimental results demonstrated that Acoustic Doppler Velocimeter (ADV) measurements were almost identical with the Realizable k–ε turbulence model results for turbulence intensity I=10%. 相似文献
8.
Design recommendations for steel plate shear wall (SPSW) systems have recently been introduced into seismic provisions for steel buildings. Response modification (R), overstrength (Ωo), and displacement amplification (Cd) factors for SPSW systems presented in design codes were based on professional experience and judgment. A numerical study has been undertaken to evaluate these factors for SPSW systems. Forty‐four unstiffened SPSW possessing different geometrical characteristics were designed based on the recommendations given in the AISC Seismic Provisions. Bay width, number of stories, story mass, and steel plate thickness were considered as the prime variables that influence the response. Twenty records were selected to include the variability in ground motion characteristics. In order to provide a detailed analysis of the post‐buckling response, three‐dimensional finite element analyses were conducted for the 44 structures subjected to the selected suite of earthquake records. For each structure and earthquake record, two analyses were conducted in which the first includes geometrical nonlinearities and the other includes both geometrical and material nonlinearities, resulting in a total of 1760 time history analyses. In this paper, the details of the design and analysis methodology are given. Based on the analysis results, response modification (R), overstrength (Ωo), and displacement amplification (Cd) factors for SPSW systems are evaluated. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
9.
Resisting urban renewal in Istanbul 总被引：1，自引：1，他引：0
Ozan Karaman 《Urban geography》2013,34(2):290-310
In this article I examine grassroots responses to state-directed urban renewal in two poor neighborhoods in Istanbul. Through detailed analysis of resident perspectives and urban association tactics, I explore various factors that shape the trajectories of resistance to urban renewal, including solidarity networks, levels of participation and trust in local neighborhood associations, strength of neighborhood identity, extra-local support, and the traditions and channels of negotiation with state actors. I argue that these factors are articulated by a distinct “politics of compensation”—a term that I borrow from Ananya Roy—that is particular to the contemporary neoliberal condition. I find that grassroots mobilizations in Istanbul do not necessarily operate in opposition to neoliberalism; in fact, many struggles remain within the conceptual space of neoliberalism and its cost-benefit calculations. These findings contribute to the emerging literature on struggles against urban renewal in the global south. 相似文献
10.
Erkan Gökaşan Hüseyin Tur Mustafa Ergin Tolga Görüm Fatma Gül Batuk Nurcan Sağcı Timur Ustaömer Ozan Emem Hakan Alp 《Geo-Marine Letters》2010,30(2):113-131
Seismic and bathymetric data from the Çanakkale Strait and its extensions onto the shelves of the Marmara and Aegean seas indicate that the strait was formed mainly by an erosional event. Four seismic units are observed on seismic profiles. The lower two of these (units 4 and 3) constitute the basement of a regionally widespread erosional unconformity (ravinement), which developed during marine isotope stage 2 (MIS 2). The two upper units (units 2 and 1), which overlie the ravinement surface, form a higher-order sequence. Sequence stratigraphic analysis indicates that units 2 and 1 deposited as lowstand and highstand systems tracts respectively, since the end of MIS 2. The transgressive systems tract is represented by a major erosional event which occurred throughout the Çanakkale sill area when the Mediterranean-Marmara Sea connection and, hence, the Çanakkale Strait was formed. The existence of the erosive ?arköy Canyon along the shelf edge of the southern Marmara Sea demonstrates that the flow direction causing the erosion was from south to north, thus proving that it was produced by Mediterranean water flowing over the sill into the Marmara Sea basin. 相似文献