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A Sequence Stratigraphic Approach To The Depositional History Analysis Of The Upper Eocene Sedimentary Succession, Northwest Of The Thrace Basin, TurkeySunnetcioglu, Mehmet Akif 01 February 2008 (has links) (PDF)
This study investigates the depositional history of the Late Eocene sedimentary record in the northwest of the Thrace Basin in a sequence stratigraphic approach and estimates the contribution of regional tectonics, basin physiography and eustasy. Late Eocene sedimentary succession was analyzed in two third-order sequences based on two major data sets / seismic reflection and well data sets. Depositional Sequence-1, represented by progradational stacking patterns, comprises the coarse-grained Hamitabat turbidite system. The base of the Sequence-1 was defined as the base of channel fill deposits in the northern shelf setting and the base of slope fan deposits in the slope setting. This boundary separates Lower-Middle and Upper Eocene sediments. In the slope setting, the Hamitabat turbidite system was analyzed in three major depocenters / Western, Northwestern and Northeastern depocenters respectively.
Hamitabat turbidite system was controlled by the interaction of regional tectonics, basin physiography and eustatic fluctuations in the Late Eocene. This study highlighted the role of the regional variables / tectonic
influence and basin morphology on the submarine canyon formation. The facies distribution was controlled by the high subsidence rate of sea-floor dominantly instead of eustasy.
Depositional Sequence-2, represented by mostly retrogradational stacking patterns, is a clastic-carbonate mixed system. Depositional Sequence-2 was subdivided into three higher-order sequences. The lower sequence boundaries were induced by the rapid relative sea-level rise. The
upper boundary of the Depositional Sequence-2 was defined as the termination of clastic-carbonate mixed system and a candidate for the Eocene-Oligocene contact.
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Determination Of The Rock Mass Characteristics And Support Systems Of The New Ulus Tunnel, AnkaraAksular, Irem 01 December 2008 (has links) (PDF)
The New Ulus Tunnel will be constructed within the andesitic terrain at
Hidirliktepe (Ankara). Excavation of the tunnel will be accomplished through blast
and drill method. Emprical methods will be consulted during the design of the
support systems as well as the slope of the portal rock face. Therefore it is essential
to perform detailed rock mass characterization studies.
In this thesis it is aimed to determine the rock mass characteristics in order
to design the rock slope of the portals and to assess the reliable support systems for
the tunnel. For this purpose laboratory tests and field investigations were conducted.
Field investigations involved detailed discontinuity measurements and borehole
drillings. In respect of laboratory tests / point load index, unit weight and uniaxial
compression strength tests were used.
The field and laboratory test results were utilized in the Rock Mass
Classification Systems (RMR, Q-system) in order to ascertain the rock mass
characteristics. By all accounts, necessary tunnel support systems were determined.
As for the portal areas, the rock face design was accomplished through kinematical
analyses. Consequently, no failure is expected at the portal rock slopes.
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Assessment Of Slope Stability For A Segment (km: 25+600-26+000) Of Antalya-korkuteli HighwayArikan, Asli Huriye 01 July 2010 (has links) (PDF)
The cut slopes at a segment between Km 25+600 and 26+000 of the Antalya-Burdur Breakaway-Korkuteli State Road to be newly constructed have slope instability problems due to the existence of highly jointed limestone.
The purpose of this study is to investigate the engineering geological properties of the units exposed at three cut slopes, to assess stability of the cut slopes, and to recommend remedial measures for the problematic sections.
In this respect, both field and laboratory studies have been carried out. The limestone exposed at the cut slopes are beige to gray, fine grained, fossiliferous, and highly jointed. It has two joint sets and a bedding plane as main discontinuities. The kinematic analysis indicates that planar failure is expected at Km: 25+900. Limit equilibrium analysis show that the cut slopes with bench have no slope instability problems except rockfalls which endanger the traffic safety. In this thesis it is recommended to covering the cut slope with wire mesh and fibre reinforced shotcrete
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Relations Between Pore Water Pressure, Stability And Movements In Reactivated LandslidesGundogdu, Bora 01 February 2011 (has links) (PDF)
Slope movements cause considerable damage to life and property in Turkey as well as in the world. Although they do not typically cause loss of life, slow landslide movements can severely damage structures, interrupt the serviceability of lifelines / and, related stabilization efforts can be too costly. Most of these slow-moving landslides are reactivated landslides in stiff clays and shales, and they are mainly triggered by rainfall induced high pore water pressures. In this study, a number of reactivated, slow-moving landslide case histories with extensive pore pressure and movement data are selected for further analysis. For these landslides, the relation between pore water pressures, factor of safety and rate of movements of the slide are investigated by using limit equilibrium and finite element methods. It is found that there is a nonlinear relationship between these three variables. Sensitivity of slow moving landslides to changes in pore water pressure is developed by defining the percent change in factor of safety and percent change in pore pressure coefficient, for 10-fold change in velocity. Such relations could especially be useful in planning required level of remediation, for example, to decide on how many meters the ground water level should be lowered at a certain piezometric location, so that the stability increases to a desired level of F.S., and movement rates are reduced to an acceptable slow rate.
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Robustness of the Oxygen Uptake Efficiency Slope to Exercise Intensity in Patients with Coronary Artery DiseaseBaba, Reizo, Tsuyuki, Kazuo, Yano, Hiroyoshi, Ninomiya, Kenji, Ebine, Kunio 02 1900 (has links)
No description available.
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OXYGEN INTAKE EFFICIENCY SLOPE: A NEW INDEX OF CARDIORESPIRATORY FUNCTIONAL RESERVE DERIVED FROM THE RELATIONSHIP BETWEEN OXYGEN CONSUMPTION AND MINUTE VENTILATION DURING INCREMENTAL EXERCISENISHIBATA, KENJI, TAUCHI, NOBUO, YOKOTA, MITSUHIRO, NAGANO, YOSHIKO, GOTO, MASAHIKO, NAGASHIMA, MASAMI, BABA, REIZO 29 March 1996 (has links)
No description available.
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Incoporating rubble mound jetties in elliptic harbor wave modelsZhang, Jianfeng 17 September 2007 (has links)
Simulation models based on the elliptic mild or steep slope wave equation are
frequently used to estimate wave properties needed for the engineering calculations of
harbors. To increase the practical applicability of such models, a method is developed to
include the effects of rubble mound structures that may be present along the sides of
entrance channels into harbors.
The results of this method are found to match those of other mathematical models
(i.e. parabolic approximation & three-dimensional solution) under appropriate conditions,
but they also deviate from results of parabolic approximations in some cases because
dissipation can create angular scattering. Comparison with hydraulic model data also
shows that this approach is useful for designing pocket wave absorbers that are used to
reduce wave heights in entrance channels.
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A Novel Approach to X-ray Mirror Bending Stability and ControlWeinbaum, Michael 22 October 2010 (has links)
A novel, no-contact approach to X-ray mirror bending control is presented here,
proposed for use on the beamlines of the European X-ray Free Electron Laser (XFEL)
project. A set of mirrors with tunable bending radii are desired, that will maintain their
optical properties even as the beam incidence causes local heating. Various mechanical
bending mechanisms have been proposed and used on other beamlines, which can take up
a lot of physical space, demanding more vacuum power, while using expensive high
precision servomotors. Rather than bend the mirror by mechanical means, it is proposed
to heat the mirror to produce the desired bending. This could work two ways. One
scenario calls for a finely tunable heat lamp to irradiate the back surface of the mirror
while the X-ray laser heats the front side. With appropriate tuning, simulations show that
this approach can keep the mirror flat, and perhaps produce a circular profile. The
second scenario is similar to the first, but a thin film of tungsten is added to the back of
the silicon mirror. This scenario calls for the temperature of the mirror to change
homogenously to affect the desired bending, and in this case the profile should be
cylindrical. In both scenarios the uneven nature of the incident radiation causes
distortions that may be undesirable. Both scenarios are simulated and it is shown that the
stress produced by a metal film may minimize this distortion. The response time of the
mirror and configuration of both the heating and cooling mechanism are also considered.
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Does Crowding Obscure the Presence of Attentional Guidance in Contextual Cueing?Fiske, Steven William 01 January 2012 (has links)
The contextual cueing effect was initially thought to be the product of memory guiding attention to the target location. However, the steep search slopes obtained in contextual cueing indicate an absence of attentional guidance. We hypothesized that crowding could be obscuring the presence of attentional guidance and investigated this possibility in 2 experiments. Crowding was manipulated by varying the density of items in the local target region in a contextual cueing task. We observed a significant reduction in search slopes between the novel and repeated conditions when crowding was reduced. Enhancing crowding eliminated the contextual cueing effect. These findings suggest that increased crowding at larger set sizes attenuates the memory-based attentional guidance in contextual cueing thereby producing steep search slopes.
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Controls on late Neogene deep-water slope channel architecture in a bathymetrically complex seafloor setting : a quantitative study along the Southeastern Caribbean Plate Margin, Columbus Basin, TrinidadRamlal, Kristie Anuradha 18 February 2014 (has links)
Slope-channels act as conduits that transport sediments from the shelf staging area to the basin floor. The Pliocene-Pleistocene section of the Columbus Basin in the deep-water slope offshore eastern Trinidad provides an opportunity to study slope-channel morphology and evolution, as well as any association between deep-water deposits, palaeo-seafloor bathymetry, shelf sediment feeder mechanism and changes in sediment supply types and volumes. Approximately 3250 km2 of 3D seismic data allow imaging and interpretation of channels within an interval between two regional surfaces termed P30 and P40. Observations of seismic cross-sections and stratal slices reveal a number of features including channels, mud diapirs, mass transport deposits (MTDs), and faulted anticlinal ridges. Channels appear leveed and unleveed, and alternate with MTDs in a cyclic vertical succession. Nineteen channels were mapped and divided into two groups based on their degree of levee development and stratigraphic position relative to MTDs. Group 1 channels, positioned below MTDs near the base of the interval, are shallowly incised, and show limited levee development. Group 2 channels, situated above MTDs, are relatively deeply incised, and have comparatively larger, well-developed levees throughout their lengths. Morphometric data from these channel groups reveal significant variability in channel width, channel depth, meander belt width, and sinuosity downslope. This variability is associated with influences of temporally equivalent local features and regional sea-floor slope changes. Increased slope gradient causes a marked increase in sinuosity. Diapirs and anticlinal ridges confine channel paths, divert their flow, and cause post-depositional deformation of both levees and channels. Levee height decreases downslope while levee width shows considerable asymmetry, which is related to occurrences of mud diapirism and MTDs. Irregularities on the upper surface of MTDs create accommodation space that confines turbidity flows, enabling ponding of sediments and volumetrically large levee construction. This accounts for dispersion of turbidity flows below the MTD which creates a series of small channels spread over a wide area, and comparatively fewer, confined channels above the MTDs with large levees. / text
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