Guest editorial     

Polat Gülkan  Haluk Eyidoğan 《Journal of Seismology》2002,6(3):285-286

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An Evaluation of Interpolation Methodologies for Generating Three-Dimensional Hydraulic Property Distributions from Measured Data   总被引：2，自引：0，他引：2  

Gerald K. Boman  Fred J. Molz  Oktay Güven 《Ground water》1995,33(2):247-258

The process of attempting to model ground-water systems requires a good understanding of the spatial variation of aquifer hydraulic properties. The capabilities of the more recent innovative flowmeters such as the electromagnetic and heat pulse flowmeters provide the sensitivity to measure ambient flows and pump-induced flows. These flowmeters provide the measurements of pump-induced vertical flows which are analyzed to obtain vertical variations in horizontal hydraulic conductivity, K(z). With discrete areal K-values, K(x, y), and vertical profiles of K, provided by multiwell testing, the essential elements are present to produce a three-dimensional hydraulic conductivity field. The advent of these new flow measuring devices has contributed much to the motivation behind this paper. This paper presents the results of applying deterministic and stochastic methodology to the three-dimensional interpolation of hydraulic properties, specifically, hydraulic conductivity, K. Three of the approaches applied in this paper are deterministic in nature, inverse-distance weighting, inverse-distance-squared weighting, and ordinary kriging, while the fourth is a stochastic approach based on self-affine fractals. All of the methods are applied to measured data collected from 14 wells at a site in the United States near Mobile, Alabama. The three-dimensional K-distributions generated by each of the methods are used as inputs to an advective based transport model with the resulting model output compared to a two-well tracer study run previously at the same site.  相似文献   

Earthquake ground motion characteristics and seismic energy dissipation     

Haluk Sucuolu  Alphan Nurtu 《地震工程与结构动力学》1995,24(9):1195-1213

The sensitivity of seismic energy dissipation to ground motion and system characteristics is assessed. It is found that peak ground acceleration, peak ground velocity to acceleration (V/A), dominant period of ground excitation and effective response duration are closely correlated with the energy dissipated by a SDOF system. Ductility ratio and damping ratio have no significant influence on the energy dissipation. An energy dissipation index is proposed for measuring the damage potential of earthquake ground motion records which includes the effects of basic excitation and response characteristics contributing to the seismic energy dissipation. The proposed index is compared with several intensity measures for the set of 94 ground motion records considered in the study.  相似文献   

Variations and Trends in Turkish Seasonal Heating and Cooling Degree-Days   总被引：2，自引：0，他引：2  

Mikdat Kadioğlu  Zekai Şen  Latif Gültekin 《Climatic change》2001,49(1-2):209-223

The potential effect of climate change on energy demand is important especially for the developing and non-oil-producing countries. Cooling and heating degree-day (CDD and HDD) concepts are among the most significant meteorological variables related to residential energy consumption. This paper presents the spatial and temporal characteristics of Turkish seasonal CDD and HDD in the context of climate change. CDD and HDD are defined objectively by truncation of the temperature series at any constant base temperature level. This leads to surpluses and deficits as deviations. The surpluses are instances for cooling and the deficits for heating. Depending on temperature fluctuations, the degree-day statistics at any location show local and seasonal variations. In this study, regional variations of seasonal HDD and CDD are mapped for Turkey and their relations to local topography and climatic features are examined with conclusive interpretations. The sequential version of Mann–Kendall rank statisticis applied to demonstrate any existence of possible non-linear trends in accumulated HDD and CDD over the seasons. Spatially coherent and statistically significant trends of HDD and CDD appear in some regions of Turkey. In general, the sign of the trends is inconsistent with General Circulation Models (GCM) predictions.  相似文献   

森林沼泽景观区化探找金技术方法——以黑龙江北部及内蒙古东北部为例     

李庆录  宋丙剑  宋贵斌 《黄金地质》2001,7(3):53-58

通过对黑龙江北部及内蒙古东北部森林沼泽景观区Au在水系沉积物和土壤中富集特征的研究,认为Au在水系沉积物中的迁移搬运距离为800～1400m,主要富集在-40目的中细粒级的粉砂和淤泥中,一般含量为0.6×10-9～1.2×10-9,大于3×10-9可形成异常.Au在土壤中的迁移搬运距离为60～100m,主要富集在-40目的B层粘土物质中,一般含量为1.1×10-9～2.0×10-9,大于6×10-9可形成异常.因此该区的化探工作适合用1∶10万水系沉积物测量工作圈定成矿有望地段,用1∶5万水系沉积物或土壤测量进行查证,在较好地段进行1∶2万(200m×40m)土壤测量工作,再于有望地段加密至100m×20m,并进行工程验证.  相似文献   

Causes, mechanism and environmental impacts of instabilities at Himmetoğlu coal mine and possible remedial measures     

Reşat Ulusay  Candan Gökçeoğlu  Harun Sönmez  Ergün Tuncay 《Environmental Geology》2001,40(6):769-786

 Since the commencement of mining at the Himmetoğlu coal mine, northwest Turkey, serious stability problems have led to interruptions in mining and some environmental effects. A geotechnical investigation was initiated in 1997 and the significant factors that influence the stability have been defined. This paper outlines the results of the field and laboratory studies associated with the causes and mechanism of the slope instabilities and their environmental impacts. The possible remedial measures to improve the stability and to minimize the environmental problems are also described. Back-analyses and data from long-term monitoring indicate that the failures occur along two or three planar surfaces by combination of faults and localized strata steepening adjacent to the faults. The stability is sensitive to changes in length of the lower part of the basal sliding surface and shear strength of the bedding surfaces in the overburden. Suitable remedial measures include slope flattening (i.e. staged bench stripping), proper drainage and spreading of a rock blanket on the pit floor to increase spoil pile stability. Received: 18 April 2000 · Accepted: 15 August 2000  相似文献   

An algorithm for the optimum design of braced and unbraced steel frames under earthquake loading     

Gülten Gülay  Hasan Bodurolu 《地震工程与结构动力学》1989,18(1):121-128

A solution technique based on the sequential linear programming (SLP) method is presented for the optimum design of braced and unbraced steel frames in seismic regions. First, the optimum rigidity distribution of the frames under static loading is computed, then the optimization procedure is repeated under the combined loading, setting lower bounds on the optimum static cross-sectional areas and increasing allowable stresses. The stiffness, stress, displacement and side constraints are included in the optimization problem. As a result, a highly non-linear mathematical programming problem is produced. A non-linear programming algorithm is offered for the solution which is based on the successive linearization of non-linear expressions and employs the simplex routine in an iterative manner. Design variables are chosen to be the free nodal displacements and the cross-sectional areas of the members, while the objective function is taken to be the minimization of the total volume of the structure. As numerical applications, optimum weights of several frames (unbraced, concentrically and eccentrically braced) under static and combined loading cases are computed and the results are compared with those available in the literature.  相似文献   

Book reviews     

A. G. Paşamehmetoĝlu  S. Valliappan 《Rock Mechanics and Rock Engineering》1990,23(3):237-238

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Development of a GIS-based monitoring and management system for underground coal mining safety   总被引：2，自引：0，他引：2  

Seda alap  Mahmut Onur Karsl&#x;olu  Nuray Demirel 《International Journal of Coal Geology》2009,80(2):105-112

Coal mine safety is of paramount concern to mining industry. Mine accidents have various causes and consequences including catastrophic failure of mine, substantial economic losses and most notably loss of lives. Therefore, any initiative in mine monitoring is of vital importance for progressing safety surveillance and maintenance.This paper presents the development of a geographic information system (GIS)-based monitoring and management system for underground mine safety in three levels as constructive safety, surveillance and maintenance, and emergency. The developed model integrates the database design and management to the monitoring system implementation which encompasses query and analysis operations with the help of web and desktop applications. Interactive object-oriented graphical user interfaces (GUIs) were developed to visualize information about the entities gathered from the model and also to provide analysis operations based on the graphical representations and demonstrations using data tables and map objects.The research methodology essentially encompasses five main stages: (i) designing a conceptual database model; (ii) development of a logical model in terms of entity-relationship (ER) diagrams; (iii) development of a physical model based on physical constraints and requirements; (iv) development of GUIs and implementation of the developed model, analysis and queries; (v) verification and validation of the created model for Ömerler underground coal mine in Turkey. The proposed system is expected to be an efficient tool for improving and maintaining healthy standards in underground coal mines which can possibly be extended to a national GIS infrastructure.  相似文献   

Effects of land-based sources on water quality in the Omerli reservoir (Istanbul,Turkey)     

Enis Morkoç  Vildan Tüfekçi  Huseyin Tüfekçi  Leyla Tolun  Fatma Telli Karakoç  Tuğba Güvensel 《Environmental Geology》2009,57(5):1035-1045

The Omerli reservoir is located on the northeastern side of the Istanbul City. It is one of the most important sources of drinking water with a surface area of 23.1 km² and a volume of 220 × 10⁶ m³ in the Marmara Region. Water quality characteristics of the lake investigated from May 2002 to April 2003 enabled us to identify the effect of waste loads on water quality of Omerli Lake. The following parameters were measured in the lake water: temperature (16.1°C), conductivity (250 μS/cm), secchi disk depth (1.9 m), dissolved oxygen (DO) (9.36 mg/L), nutrients [ortho-phosphate (78.9 μg/L), nitrate + nitrite (707.5 μg/L) and ammonia-nitrogen (264 μg/L)], chlorophyll a (9.43 μg/L), total organic carbon (3.33 mg/L), total suspended solids (4.54 mg/L), total poly aromatic hydrocarbon (t-PAH) (0.69 μg/L) and copper (24.5 μg/L). T-PAH (16.5 mg/g-dry-w), Cu (96.5 μg/g-dry-w), organic carbon (org-C) (2.0%) and N (0.44%) were determined in the surface sediment. The values of chlorophyll a and DO in the upper layer were relatively high and low secchi disk depths indicates eutrophic state. There are five channels discharging water, including waste water, into the lake. All channels were sampled during six occasions in order to cover variations between seasons. The following parameters were measured: total organic carbon, total phosphorus, total kjeldahl nitrogen, ammonia and total suspended solids with the flow rates. The Göçbeyli stream has the highest flow into the lake (1.5 × 10⁸ m³/year) but most of the nutrients were discharged from the Pa?aköy channel. It is accounting for 81% of ammonia and 80% of total phosphorus into the lake. Three scenarios were run using AQUATOX model: (1) all existing inflows are discharging into the lake (present situation); (2) none is discharging; (3) all are discharging except the Pa?aköy channel. The first scenario produced concentrations consistent with measurements in the lake. In all stations, a phytoplankton peak value was predicted during November and December 2002, and January 2003. In the second scenario, as expected, a significant decrease in the concentrations was predicted. In the third scenario, a small improvement in the water quality was obtained. To significantly improve the state of the lake, instead of entering Pa?aköy channel, wastewater should bypass the lake.  相似文献