排序方式： 共有15条查询结果，搜索用时 31 毫秒
1.
2.
Ömer Emre Tamer Y. Duman Selim Özalp Fuat Şaroğlu Şeyda Olgun Hasan Elmacı Tolga Çan 《Bulletin of Earthquake Engineering》2018,16(8):3229-3275
We have updated the active fault map of Turkey and built its database within GIS environment. In the study, four distinct active fault types, classified according to geochronological criteria and character, were delineated on the 1:25,000 base map of Turkey. 176 fault segments not included in the former active fault map of Turkey, have been identified and documented. We infer that there are 485 single fault segments which are substantially potential seismic sources. In total 1964 active-fault base-maps were transferred into the GIS environment. Each fault was attributed with key parameters such as class, activity, type, length, trend, and attitude of fault plane. The fault parameters are also supported by slip-rate and seismogenic depth inferred from available GPS, seismological and paleoseismological data. Additionally, expected maximum magnitude for each fault segment was estimated by empirical equations. We present the database in a parametric catalogue of fault segments to be of interest in earthquake engineering and seismotectonics. The study provides essential geological and seismological inputs for regional seismic hazard analysis of all over Turkey and its vicinity. 相似文献
3.
The present paper is concerned with determining the effect of thickness variation on collapse pressure of seamless pipes. There exists extensive information on the effects external pressure has on pipelines. A substantial amount of literature deals with results of analysis, numerical modelling and testing of pipes those are gradually subject to external pressure. This knowledge has been incorporated into standards which are intended for designing linepipe operating in deepwater locations. One such example is the DNV-OS-101 (DNV, 2007) Submarine Pipeline Systems standard. This code only addresses pipes with a nominally uniform wall thickness making it inadequate for designing seamless pipe which is prone to thickness variation arising from the manufacturing process. The DNV (2007) code effectively ignores the problem as it simply provides a vague statement regarding a conservative value of wall thickness that should be used in the design calculations.The present paper uses finite element analysis (FAE) modelling to predict the external pressure acting on the pipes. The present paper explains the manner in which FEA models will be used to study the effect wall thickness variation will have on the pressure at which the pipe will collapse. An improvement to the DNV (2007) code is then suggested by interpreting the results of the FEA models. The case study that follows provides insight on the savings the improved method is projected to offer. 相似文献
4.
Heavy metal pollution and acid drainage from the abandoned Balya Pb-Zn sulfide Mine,NW Anatolia,Turkey 总被引：5，自引：0，他引：5
Atilla?Aykol Murat?BudakogluEmail author Mustafa?Kumral Ali?H.Gultekin Melih?Turhan Vildan?Esenli Fuat?Yavuz Yuksel?Orgun 《Environmental Geology》2003,45(2):198-208
This study was conducted to determine the effects of the waste-rock dump (WRD) of the underground polymetallic Balya Mine on the Kocacay River and eventually on Lake Manyas in Turkey. Data presented in this paper include geochemical characteristics of various kinds of water (mine, surface and groundwater) and of suspended-particle samples in the vicinity of Balya. The more polluted mine waters have low pH and high conductivity, while high concentrations of Zn, Cd, Mn tend to be found in the dry and wet seasons. High concentrations of Pb, As, Cr, Cu and S appear only in the wet season. The sources of the heavy metal concentration within the Kocacay River are leached waste, surface run off, and overflow from the spillway of the WRD. To minimize the formation of acids and dissolved metal, and for the remediation of the harmful effects of extreme contamination conditions, it is recommended that lime or alkali materials and organic carbon be added to simulate the action of sulfate-reducing bacteria. 相似文献
5.
Predicting longitudinal dispersion coefficient in natural streams by artificial intelligence methods
In this study, three artificial neural network methods, i.e. feed forward back propagation, the radial basis function neural network, and the generalized regression neural network are employed to compute the longitudinal dispersion coefficient in order to evaluate its behaviour in predicting dispersion characteristics in natural streams. These methods, which use hydraulic and geometrical data to predict dispersion coefficients, can easily be applied to natural streams and are proven to be superior in explaining their dispersion characteristics more precisely than existing equations. This method of predicting the longitudinal dispersion coefficient in river flows was tested on 65 data sets, obtained by researchers from 30 rivers in the USA. Results using the models are compared with results obtained in many other studies, and are shown to be more accurate than the other methods considered. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
6.
Three-dimensional fully nonlinear waves generated by moving disturbances with steady forward speed without motions are solved using a mixed Eulerian–Lagrangian method in terms of an indirect boundary integral method and a Runge–Kutta time marching approach which integrates the fully nonlinear free surface boundary conditions with respect to time.A moving computational window is used in the computations by truncating the fluid domain (the free surface) into a computational domain. The computational window maintains the computational domain and tracks the free surface profile by a node-shifting scheme applied within it. An implicit implement of far field condition is enforced automatically at the truncation boundary of the computational window.Numerical computations are applied to free surface waves generated by Wigley and Series 60 hulls for the steady problem. The present numerical results are presented and compared with existing linear theory, experimental measurements, and other numerical nonlinear computations. The comparisons show satisfactory agreements for these hydrodynamic problems. 相似文献
7.
Catherine Kuzucuoğlu Aurélien Christol Damase Mouralis Ali‐Fuat Doğu Ebru Akköprü Monique Fort Daniel Brunstein Halil Zorer Michel Fontugne Mustafa Karabiyikoğlu Stéphane Scaillet Jean‐Louis Reyss Hervé Guillou 《第四纪科学杂志》2010,25(7):1124-1137
Sedimentological and geomorphological studies of terraces around Lake Van (1647 m) provided a preliminary framework for lake‐level variations. The elevations of terraces and past lake level were measured with a differential global positioning system. A chronology is developed using 234U/230Th dating of travertines, 39Ar/40Ar dating of pyroclastites and 14C dating of organic matter. Facies and stratigraphic correlations identify four transgressions (C1′, C1″, C2′ and C2″), each followed by a regression which ended with low lake levels that caused river incision and terrace formation. Evidence of the oldest transgression (C1′) is found in the uppermost reaches of valleys up to 1755 m, an altitude higher than the present lake threshold (1736 m). This C1′ transgression may be related to pyroclastic flows which dammed an outlet located in the western part of the lake basin and which is dated to before 105 ka. After 100 ka, a second transgression (C1″) reached 1730/1735 m, possibly related to a younger ignimbrite flow, in association with high water inflow (warm and/or wetter conditions). The two younger transgressions reached 1700–1705 m. The first one (C2′) is dated to 26–24.5 cal. ka BP and the second one (C2″) to 21–20 cal. ka BP. Available data suggest that the long‐term lake‐level changes responded mainly to climate oscillations. Additional events such as river captures caused by volcanic falls filling valleys, tectonism, erosion and karstic diversion may have impacted these long‐term lake‐level changes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
8.
9.
Numerical solutions for the hydroelastic problems of bodies are studied directly in the time domain using Neumann–Kelvin formulation. In the hydrodynamic part of problem, the exact initial boundary value problem is linearized using the free stream as a basis flow, replaced by the boundary integral equation applying Green theorem over the transient free surface Green function. The resultant boundary integral equation is discretized using quadrilateral elements over which the value of the potential is assumed to be constant and solved using the trapezoidal rule to integrate the memory or convolution part in time. In the structure part of the problem, the finite element method is used to solve the hydroelastic problem. The Mindlin plate as a bending element, which includes transverse shear effect and rotary inertia effect are used. The present numerical results show acceptable agreement with experimental, analytical, and other published numerical results. 相似文献
10.
This paper presents a neural network (NN) controller for a fishing vessel rudder roll system. The aim of this study is to build a NN controller which uses rudder to regulate both the yaw and roll motion. The neural controller design is accomplished with using the classical back-propagation algorithm (CBA). Effectiveness of the proposed NN control scheme is compared with linear quadratic regulator (LQR) results by simulations carried out a fishing vessel rudder roll stabilizer system. 相似文献