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Quantitative Flood Risk Assessment With Application In TurkeyKeskin, Fatih 01 September 2012 (has links) (PDF)
Floods can result in enormous causalities and huge economic losses in urban and rural regions. In recent years, while assessing the damage, risk analysis and assessment has become an important tool in addressing uncertainty in flood hazards. The lack of knowledge about the water extend, water depth, water velocity and potential damage in case of flood increase the vulnerability of the people to disasters in the flood region. Especially this information is valuable for city planners and decision makers. In case of new settlement area selection, correct decision can be taken by the help of this information. This type of information can be taken from hydraulic models as 1D or 2D. On the other hand, two dimensional (2D) hydraulic modeling becomes a need with increasing trends of very high speed computers and models instead of one dimensional (1D) ones. The ability of solving complex structures within few minutes enhances the use of 2D modeling with the integration of wave motion. In addressing the uncertainty, GIS becomes an important tool in risk assessment by integrating the flood depth, extend and vulnerability issues for definition of the quantitative risk. In this study, 1D and 2D hydraulic modeling is applied and combined with the quantitative vulnerability factors in Dalaman Plain-Turkey. Results show that the area is vulnerable to flood and high monetary damages can be seen in case a flood in the region.
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Water Circulation And Yacht Carrying Capacity Of Fethiye BayDzabic, Miran 01 September 2012 (has links) (PDF)
Coastal regions provide a lot of resources and benefits for all the humankind. For economic growth, these resources are needed. On the other hand, coastal resources should be maintained and preserved in some limits. Sustainable development is aimed to set a balance between economic growth and preserving the nature. Determination of the yacht carrying capacity is a major step for sustainable development.
In this thesis study wind-induced water circulation in semi-enclosed basins are carried out in order to reach the yacht carrying capacity for Fethiye Bay. Hydrodynamics of bays is very complex, mainly affected by wind and wave climate and sea bottom topography. The sea bed profiles at the bay changes under winter and summer storms of different speeds and directions. This case study will be carried out with the developed methodology. The present structure of Fethiye Bay will be analyzed and necessary measurements will be proceeded. Moreover, two more cases will be studied besides the present conditions. Circulation models will be applied to
the study case according to reached data. For this purpose, Finite Volume Coastal Ocean Model (FVCOM) numerical model will be used.
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T-Cell Protein Tyrosine Phosphatase, a Regulator of the PDGF Signaling PathwayKarlsson, Susann January 2009 (has links)
Platelet-derived growth factor (PDGF) is a potent stimulator of cell growth, survival and motility. PDGF exerts its function by binding to specific tyrosine kinase receptors, initiating receptor auotphosphorylation and initiation of specific signaling pathways that regulates the cellular response. It is critical that these signals can be modulated and terminated, since over-activation of signaling pathways are often found in diseases, such as cancer. Protein tyrosine phosphatases (PTPs) counteract the tyrosine kinases by dephosphorylating proteins, thereby playing a crucial role in the control of signaling events. The aim of this thesis has been to study the regulation of PDGF receptor signaling by the T-cell protein tyrosine phosphatase (TC-PTP). In the first two studies, we demonstrated that loss of TC-PTP specifically redirected the PDGF β-receptor towards a rapid Rab4a-dependent recycling after ligand-induced internalization. Furthermore, we found that the sorting of activated PDGF β-receptor into the recycling pathway was dependent on sequential PKCα and Rab4a activation. Since the PDGF α-receptor did not recycle in the absence of TC-PTP, this study displays the first evidence of differences in trafficking of the PDGF receptor family members. PDGF β-receptor recycling was also induced by activating PKCα through the LPA receptor. The LPA-induced PDGF β-receptor recycling correlated with increased receptor phosphorylation and cell migration at low concentrations of PDGF-BB. The data suggests that PKCα activation could serve as a point of cross-talk between receptor families, regulating the duration and magnitude of PDGF β-receptor signaling. In the last study, we searched for novel substrates for TC-PTP downstream of the PDGF β-receptor, and identified the pyruvate kinase M2, PK-M2, as a possible substrate. PK-M2 is expressed in cells that proliferate rapidly, including tumor cells. Our data suggests that TC-PTP can interact with the glycolytic complex, affecting the activity of PK-M2 and hence, altering the glucose metabolism for proliferating tumor cells.
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Optimal Channel DesignAksoy, Bulent 01 September 2003 (has links) (PDF)
The optimum values for the section variables like channel side
slope,bottom width,depth and radius for triangular,rectangular,
trapezoidal and circular channels are computed by minimizing the cost
of the channel section.Manning &rsquo / s uniform flow formula is treated as a
constraint for the optimization model.The cost function is arranged to
include the cost of lining,cost of earthwork and the increment in the
cost of earthwork with the depth below the ground surface.The
optimum values of section variables are expressed as simple functions
of unit cost terms.Unique values of optimum section variables are
obtained for the case of minimum area or minimum wetted perimeter
problems.
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Discharge Estimations With Regression Analysis Using Basin Parameters And Gis TechniquesPekpinarli, Hakan 01 June 2005 (has links) (PDF)
Discharge estimations at certain cross sections of streams are very important for hydrologic studies especially for designs. In this study, it is aimed to determine regional mathematical equations that represent annual and monthly average discharges at desired locations using basin characteristics obtained with Geographical Information Systems (GIS) techniques and regression analysis.
Study area covers three river basins, which are Gediz, Kü / ç / ü / k Menderes and Bü / yü / k Menderes. The data used are Digital Elevation Model (DEM), monthly average discharges observed at stream gauging stations and monthly total precipitation data from the precipitation observation stations in the study area. Stream networks are delineated from DEM using a GIS software. The basin parameters obtained from DEM are drainage area, total river length, main channel slope, main channel length and mean basin slope. Precipitation amount is also included in the analyses as the sixth parameter to improve the results. Using these parameters annual and monthly average discharge equations are determined and the best equation for each month is found based on the adjusted coefficient of determination values and stepwise regression analysis. Three models, each representing a different basin and a general model that represents the whole study area are developed. The verification of the models is made using the discharges at the additionally chosen stations that are not included in the model development. An interface that acquires the drainage area for a certain cross section and estimates the discharge according to the desired regression equation is written using arc objects and visual basic programming language. At the end, regression analysis results of the models are assessed and interpreted.
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Effect Of Hydraulic Parameters On The Formation Of Vortices At Intake StructuresBaykara, Ali 01 January 2013 (has links) (PDF)
The aim of this experimental study was to investigate the hydraulic conditions at which air-entraining
vortices would form in front of horizontal intakes and to determine the ways of eliminating the
formation of these vortices by testing anti-vortex devices. For these reasons, a series of experiments
were conducted in an experimental setup composed of a reservoir having the dimensions of 3.10 m x
3.10 m x 2.20 m and a pump connected to the intake pipe. Within the reservoir, between the concrete
side walls adjustable plexiglass side walls were placed to provide the desired wall clearance for the
intake pipes. Six pipes of different diameters / 5 cm, 10 cm, 14.4 cm, 19.4 cm, 25 cm and 30 cm were
horizontally mounted on the front side of the reservoir one by one, and for each case, a wide range of
discharges was provided from the reservoir by the pump.
Under symmetrical approach flow conditions and zero bottom wall clearance, the experiments were
repeated for each intake pipe and the &ldquo / critical submergence depths&rdquo / for the tested discharges were
determined. At some of the discharges, the effect of horizontal plates located on the top of the pipe
entrance as anti-vortex devices on the elimination of the vortices was investigated. The measured
critical submergence depths were related in dimensionless form to the relevant dimensionless
parameters and empirical equations were derived. These equations were compared with similar ones
available in the literature and it was shown that the agreement between them was quite good.
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Teacher professional development and communities of practiceHirtz, Janine Renee Marie 05 1900 (has links)
The larger research project seeks to examine the role of technology and factors that
influence its overall use and efficacy in supporting a community of teachers engaged in
professional development. This thesis examines factors that appear to influence teacher
participation in the online community of practice engaging in an overarching research project
conducted by Dr. Balcaen and a team from UBC O Faculty of Education and funded by the
Southern Alberta Professional Development Consortium (SAPDC). The two groups are
acting in partnership for supporting and sustaining communities of practice in social studies
in southern Alberta. SAPDC is allowing teachers release time to engage in the project while
TC² is providing professional development for the participant teachers to become proficient
at embedding TC² critical thinking tools into their classroom practices. Various technologies
are used during this study as part of the design of providing professional development for the
participants including supporting an online community presence. The guiding question for
this thesis is: In a blended approach of face-to-face and online supported professional
development for embedding critical thinking into the new social studies curriculum, what
significant factors appear to influence teacher participation in the online community of
practice during the first year of the project?
Overall results during the first year of this project show that various technologies
used during the project are valuable and effective in nurturing this community of practice by
enabling and promoting collaboration, communication, and the completion and delivery of
products to be used in teaching the new curriculum. I also examine negative factors that
appear to prevent some teachers’ technology use and online participation and collaboration
during this project. Findings show that there are several significant factors that influence
participation in the online community and while some participants are reluctant to engage or
enter the online environment, others have emerged as leaders and play a significant role in
building and sustaining the community of practice. These results provide critical information
about implementing and integrating an online component and using technology to sustain
communities of practice engaged in this form of teacher professional development.
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Kinetics of Anionic Surfactant Anoxic DegradationCamacho, Julianna G. 2010 May 1900 (has links)
The biodegradation kinetics of Geropon TC-42 (trademark) by an acclimated culture was investigated in anoxic batch reactors to determine biokinetic coefficients to be implemented in two biofilm mathematical models. Geropon TC-42 (trademark) is the surfactant commonly used in space habitation. The two biofilm models differ in that one assumes a constant biofilm density and the other allows biofilm density changes based on space occupancy theory. Extant kinetic analysis of a mixed microbial culture using Geropon TC-42 (trademark) as sole carbon source was used to determine cell yield, specific growth rate, and the half-saturation constant for S0/X0 ratios of 4, 12.5, and 34.5. To estimate cell yield, linear regression analysis was performed on data obtained from three sets of simultaneous batch experiments for three S0/X0 ratios. The regressions showed non-zero intercepts, suggesting that cell multiplication is not possible at low substrate concentrations. Non-linear least-squares analysis of the integrated equation was used to estimate the specific growth rate and the half-saturation constant. Net specific growth rate dependence on substrate concentration indicates a self-inhibitory effect of Geropon TC-42 (trademark). The flow rate and the ratio of the concentrations of surfactant to nitrate were the factors that most affected the simulations. Higher flow rates resulted in a shorter hydraulic retention time, shorter startup periods, and faster approach to a steady-state biofilm. At steady-state, higher flow resulted in lower surfactant removal. Higher influent surfactant/nitrate concentration ratios caused a longer startup period, supported more surfactant utilization, and biofilm growth. Both models correlate to the empirical data. A model assuming constant biofilm density is computationally simpler and easier to implement. Therefore, a suitable anoxic packed bed reactor for the removal of the surfactant Geropon TC-42 (trademark) can be designed by using the estimated kinetic values and a model assuming constant biofilm density.
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Determination Of Computational Domain Boundaries For Viscous Flow Around Two Dimensional BodiesBasa, Mustafa Mazhar 01 November 2006 (has links) (PDF)
Borders of flow field around immersed bodies can be extended to long distances
since there are no physical boundaries. In computational practice however, the flow
domain must be restricted to a reasonable size by imposing appropriate boundary
conditions at the edges of the computational space. In this thesis work, streamlines
obtained from potential flow solution in a relatively large spatial domain are utilized
to specify the boundaries and boundary conditions for a more restricted
computational domain to be used for detailed viscous flow computations. A grid
generation code is adopted for generation of unstructured triangular grid systems for
domains involving multiple immersed bodies of any shape at arbitrary orientations
such as a group of tall buildings in horizontal plane. Finite volume method is used in
the solution of Laplace equation for the stream function. A deformation modulus is
introduced as a probe parameter to aid locating the viscous flow boundaries. The
computer code acts as a preprocessor for viscous flow computations, specifying the
computational boundaries, the boundary conditions and generating the computational
grid.
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Forced Hydraulic Jump On Artificially Roughened BedsSimsek, Cagdas 01 January 2007 (has links) (PDF)
In the scope of the study, prismatic roughness elements with different longitudinal spacing and arrangements have been tested in a rectangular flume in order to reveal their effects on fundamental characteristics of a hydraulic jump. Two basic
roughness types with altering arrangements have been tested. Roughness elements of the first type extends through the channel width against the flow with varying length
and pitch ratios for different arrangements. The second type is of staggered essence and produced by piecing the roughness elements defined in the initial type into three
parts which are equal in length. The doublet formed from the pieces on the sides is shifted to the consequent row to make two successive roughness rows encapsulate the channel span completely. Staggered roughness type is formed with the repetition of this arrangement along the flume. Independent of their type and arrangement, the entirety of roughness elements are embedded in the channel bed in order to avoid
their protuberance into the flow, based on the presumption that the crests of the roughness elements levelled with the channel inlet would be less exposed to caving effects of flow than the protruding elements.
In the study, influence of the proposed roughness elements on the fundamental engineering concerns as the length, height (tail water depth) and energy dissipation capacity of hydraulic jumps has been questioned in the light of empirical work and related literature on forced and smooth hydraulic jumps.
At the final stage of the study, it was concluded that both strip and staggered roughness have positive effects on the characteristics of hydraulic jump given above. 3-7% more energy dissipation was observed in jumps on rough beds compared to classical hydraulic jumps. For tailwater dept reduction, whereas strip roughness provided 5-13%, staggered roughness led to 7-15% tailwater depth reduction
compared to classical hydraulic jump. While strip roughness reduced jump length around 40%, 35-55% reduction was observed with staggered roughness when compared to classical hydraulic jump.
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