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Three Dimensional Dynamic Response Of A Concrete Gravity DamYilmazturk, Sema Melek 01 January 2013 (has links) (PDF)
Hydroelectric power is a commonly used alternative source of energy in developing countries. In this regard, concrete gravity dams are the most preferred dam type especially with the developments in the engineering industry. Roller compacted concrete became more popular in dam construction due to its advantages of speed and economy. Several methods are used for the design of concrete gravity dams by analyzing the dam response under static and dynamic loads. This study provides three dimensional linear dynamic analysis of roller compacted concrete gravity dam with a complete dam-foundation-water interaction by using EACD-3D-08 program. Foundation flexibility was included with damping and mass using boundary elements. Three dimensional solid elements were used for the idealization of the dam and water with using finite element methods. Compressibility of water with reservoir absorption was studied. In the light of USACE, performance criteria of linear analyses were assessed. Parametric study was conducted to determine the most influential parameters on the dam response. The importance and necessity of three dimensional analyses were investigated by comparing with linear two dimensional analyses. Linear analyses were then compared with three dimensional nonlinear analyses. In conclusion, the realistic dam seismic response can only be obtained by using three dimensional linear analyses with full interaction of dam-foundation-water.
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Experimental Investigation Of Local Scour Around Bridge Pier GroupsOzalp, Murat Can 01 January 2013 (has links) (PDF)
It is an important task that design engineers in practice predict the local scour around bridge piers as accurately as possible because excessive local scour around bridge piers unbalance and demolish the bridges. Many equations have been proposed previously by various researchers, based on their experimental findings, but no general method has been developed so far due to the complexity of the topic. In the present study two new bridge pier groups were employed to investigate the inclination effect of the most upstream and downstream piers on the local scours around all piers. Total of 72 experiments have been conducted with 3 inclination angles, one of which representing the vertical case, each experiment lasting 6 hours, under uniform flow and clear-water conditions for a range of water depths and flow velocities on the uniform bed material. It is clearly observed and measured that the amount of local scour reduces substantially by the effect of inclination in the group piers, especially the reduction in the scour around the most upstream pier is found notable. Based on the experimental data, regression analyses are made and an empirical scour depth equation is developed for each individual pier in the pier groups studied. Comparisons with the similar studies performed by other researchers have been made and the results discussed.
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Demonstrationsutrustning för M2M tillämpning / Equipment for demonstration of M2M applicationKarlsson, Patrik January 2004 (has links)
Detta examensarbete är ett utvecklingsarbete av demonstrationsutrustning för enkel visning av fördelarna med M2M-tekniken vid insamling av mätdata och automatisk övervakning. Arbetet består av en praktisk del, som utgörs av demonstrationsväskan, och en mer teoretisk del, som utgörs av demonstrationsprogrammet. Programmet har utvecklats till att med ett mätkort kopplat till en PC samla in mätvärden (spänningar), dessa skickas sedan som ett SMS med ett GSM-modem till en mottagare. Mottagaren kan vara en serviceman som vill ha felmeddelanden från utrustning inom dennes ansvarsområde, mottagaren kan även vara en server som rymmer en databas vilken används för att spara viktiga mätvärden för längre tid, t.ex. loggning av elförbrukning hos något kraftbolags kund. Det hela har alltså resulterat i ett färdigt och väl fungerande program, som utför just det som är uppdraget ovan. Mätresultatenhar tillräcklig noggrannhet för detta uppdrag om att demonstrera fördelarna med M2M-tekniken, och mätresultatet kommer även fram till mottagaren i sin rätta form. Detta betyder att M2M Communication AB nu kan demonstrera vinsten med M2M-tekniken för potentiell kund på ett enkelt och förklarande sätt. Integrerat i demonstrationsutrustningen har nu också företaget fått en enkel och självklar utrusning för att i praktiken se hur nya givare och annan utrusning fungerar ihop med ComHost 300 som är företagets primära produkt. / The goal with this master thesis is to develop a simple equipment to show the advantage of using M2M-technic when collect measured data and when using automatic monitoring of alarm and sensors. The thesis is divided in two parts, a practical part that corresponds to a case with sensors and equipment. The case is used to collect measure data to be used when demonstrating the theoretical part, which corresponds to the software program. The software program is developed to measure voltage with the data acquisition card, and then send them as a SMS text message via the GSM network. For this tasks the software also have to control the GSM-modem. This text message is either sent to a computer for logging in a database, or to the service department who owns the equipment measured. This work has ended up in well function software that can be installed on a PC-system with a Windows 2000(tm) operation system. The accuracy on the measured data is good enough for the task to demonstrate the function of the M2M-technic. The text message is also arrive to the receiver as expected. The result of this master thesis ends up giving the company M2M Communication AB the possibility to demonstrate the M2M-technic on a simple and explaining manner for a potential customer. Integrated in the new equipment the company also has been given a possibility to test new sensors and signal sources in a real world M2M test.
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A One-line Numerical Model For Shoreline Evolution Under The Interaction Of Wind Waves And Offshore BreakwatersArtagan, Salih Serkan 01 July 2006 (has links) (PDF)
A numerical model based on one-line theory is developed to evaluate the wind wave driven longshore sediment transport rate and shoreline change. Model performs wave transformation from deep water through the surf zone and computes the breaking parameters. The formula of longshore sediment transport rate used in the numerical model is selected as a result of comparative studies with the similar expressions and the field measurements. Offshore breakwater module of the numerical model is developed to compute the change of shoreline behind single or multiple offshore breakwaters. The validity of the numerical model was confirmed by comparing model results with the shoreline change given within the sheltered zone behind the offshore breakwaters. A series of offshore breakwaters are hypothetically proposed for a case study where a series of groins were constructed whose numerical model results qualitatively matched well with the field measurements. The results of the influences of offshore breakwaters on the shoreline predicted by the model are discussed comparatively with the case study.
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Reliability Based Water Distribution Network DesignAkkas, Izzet Saygin 01 November 2006 (has links) (PDF)
The need of water and the limited sources, force the researchers to find the most economical and feasible solution in the design of a water distribution network. In this study, reliability and optimization of a water distribution network are taken into account together in the design stage of the network. The relationship between reliability of a water distribution network and its cost is examined during the design of a water distribution network. A methodology for deciding the reliability level of the selected design is proposed by examining the reliability-cost relationship. The design alternatives for the case study area are obtained by the aid of a commercially available software WADISO employing partial enumeration optimization technique. The reliability value for each of the design alternative is calculated according to Misirdali (2003)&rsquo / s adaptation based on the methodology proposed by Bao and Mays (1990) by the aid of a hydraulic network solver program HapMam prepared by Nohutç / u (2002). For purposes of illustration, the skeletonized form of Ankara Water Distribution Network subpressure zone (N8-1) is taken as the case study area. The methodology in this study, covering the relation between the reliability and the cost of a water distribution network and the proposed reliability level can be used in the design of new systems.
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Calibration Of A Grate On Sloping ChannelSipahi, Sabri Ozgur 01 December 2006 (has links) (PDF)
In this study a setup is designed and constructed in the Hydromechanics Laboratory of Middle East Technical University in order to observe the flow through grate inlets under different flow and geometry conditions. The rate of interception of flow is determined over a rectangular channel through preliminary experiments run on the tilting flume. The performance of the new set setup has been examined and grate efficiency is obtained both in terms of longitudinal slope and the Froude number. The results which are obtained show that the setup can be used to conduct experiments to obtain a general expression for grate efficiency.
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Wind And Wind Wave Climate Research Along The Southern Part Of Black SeaCaban, Seckin 01 July 2007 (has links) (PDF)
Winds and wind wave climate are two important phenomena for Black Sea basin. Wind wave climate has an important role on design of coastal structures and naval transportation. Despite this fact the wind wave climate is not well known for the Turkish coasts because of limited studies on this subject. The purpose of the present study was to further understand wind and wind wave climate along the Black Sea coastline of
Tü / rkiye. For this purpose wind and wind wave data for every 65 months is obtained from ECMWF for and analyzed for 12 locations situated along Black Sea coast of Turkey. For every location the wind [Berkü / n,2007] and wind wave roses, significant wind wave height vs. Mean wave period
relations, extreme probability distribution and log-linear cumulative probability distribution are presented. Also a comparison with previous studies is given for better understanding the wind and wave climate better.
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Modeling Of The Flood Regimes In Coupled Stream-aquifer SystemsKorkmaz, Serdar 01 December 2007 (has links) (PDF)
In this study, hydrogeological modeling of the Somme river basin situated in the north of France was made with special emphasis on the stream-aquifer interaction. The coupled model developed at Ecole des Mines de Paris was used. Geographic Information Systems (GIS) tools were incorporated during all the stages of modeling process for both preparation of input data and visualization of the results of simulations. Initially, the process began with Digital Elevation Model (DEM) analysis. Afterwards, the surface and aquifer grids were generated by using nested grid generators and refinement was made on the stream network and subcatchment boundaries in order to increase the accuracy of numerical solution. In order to run the surface model, meteorological forcing, land use and soil type data were acquired. Surface model was used to partition the precipitation into evapotranspiration, infiltration and surface runoff components. A steady-state piezometric head distribution was computed by the groundwater model to serve as an initial condition to the coupled model. The flow in the unsaturated zone was simulated by using Nash cascade model. The unsteady groundwater and surface flow simulations were performed by taking into consideration the stream-aquifer interaction on a daily time step. The calibration and validation were realized by using the streamflow and piezometric head measurements distributed around the basin. The strong groundwater influence on the
hydrology of the basin is well represented by the model. Comparisons of predicted flooded areas in year 2001 were made with other models and a satellite derived image. In the end, several sensitivity analyses were performed for several parameters concerning the groundwater flow.
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Wind And Wind Wave Climate For Turkish Coast And Application To Aegean And Mediterrenean SeaAldogan, Serhan 01 July 2008 (has links) (PDF)
The wind waves have significant effects on small craft and fisheries. Therefore, wind wave climate has an important role in the design and operation of fishing harbors and harbors for small craft. The purpose of this study is to identify the wind wave climate along the eastern part of the Mediterranean Sea coastline of Tü / rkiye. For this purpose, wind wave data for a certain period is obtained from ECMWF for the analysis. Moreover, the data will be analyzed for locations selected along the Turkish coast using a special software developed for this thesis study. For every location, the wind wave roses, significant wind wave height versus mean period of primary wind relations, extreme probability distribution, and log-linear cumulative probability distributions will be presented. By the help of software developed, it will be possible to analyse any coordinate using ECMWF data.
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Comparative Study On Sediment Transport Equations For Delta Formations In ReservoirsPulcuoglu, Basar 01 May 2009 (has links) (PDF)
In this study, a qualitative and comparative investigation on sediment transport equations used in prediction of rserevoir sedimentation is presented. 32 sediment transport equations, which are selected by literature review on sand and gravel size ranges, grouped according to the median particle sizes on which their derivation based. In order to compare these equations computer program DELTA, which is a one dimensional simulation program developed by Graf and Altinakar (1998) for the prediction of delta formation in resrvoirs, is used. Computer simulation is performed within each group of sediment transport equations in order to determine the most suitable equation for corresponding median diameter of sediment particles. 8 of the equations gave simulation results that are in good agreement with average values related to delta deposition extent, height and location in the reservoir. The effects of river slope change and median diameter change on delta deposition also investigated and simulation results are compared with previous model studies.
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