scholarly journals Effect of Structure of Internal Waves on Energy Transfer and Flow Control Between South and Middle Basins of Caspian Sea

2016 ◽  
Vol 10 (3) ◽  
pp. 33
Author(s):  
Ashrafoalsadat Shekarbaghani
Keyword(s):  
Energy Transfer ◽  
Internal Waves ◽  
Caspian Sea ◽  
Density Ratio ◽  
Vertical Direction ◽  
Horizontal Velocity ◽  
Theoretical Studies ◽  
Exchange Flow ◽  
Vertical Movements ◽  
Stratified Structure

In this study, role of internal waves in controlling stratified exchange flows between south and middle basins of Caspian Sea and energy transfer have been studied. The studies have been conducted based on field and theoretical studies based on numerical calculations. In this investigation, Caspian Sea has been considered as stratified and Boussinesq approximation has been considered. In equations governing the movement, cohesion and compressibility have been neglected. In the field studies, investigation of density profiles indicate signs of stratified structure which so far has been attributed to dual distribution convection phenomenon, but by considering density ratio profile and values of density ratio which are mostly negative numbers, the factor causing stratified structure of Caspian Sea can be attributed to existence of internal waves. Density field in these two basins indicate that the middle basin has higher average density compared to the south basin, this fact can cause creation of a gravity exchange flow. This exchange flow causes creation of internal waves in this sea that can have a modal structure towards vertical direction. In theoretical studies, the two middle and south basins of Caspian Sea are networked in two dimension x-z systems and equations governing movement are solved through a numerical method by using finite difference method and the vertical velocity values obtained in 290 points of the network was almost 10<sup>-6</sup> to 10<sup>-4</sup> m/s, meaning that vertical movements are much smaller. Values obtained for horizontal velocity are almost 10<sup>-3</sup> to 10<sup>-1</sup> m/s. Vertical and horizontal velocity profiles obtained from solution of these equations and also density profile obtained in four integration periods indicate that as a result of passage of gravity flow between the two basins, density in various points of the two basins change. The structure created from internal waves on the crest causes creation of shear strata observed. This structure can be effective in exchange of the two basins. Therefore, in transfer and energy conversion, identification of the created strata is of a high importance.

scholarly journals Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles

2012 ◽  
Vol 3 ◽  
pp. 629-636 ◽  
Author(s):  
Gilad Gotesman ◽  
Rahamim Guliamov ◽  
Ron Naaman
Keyword(s):  
Energy Transfer ◽  
Charge Transfer ◽  
Horizontal Plane ◽  
Quartz Substrate ◽  
Vertical Direction ◽  
Time Resolved ◽  
Transfer Processes ◽  
Donor And Acceptor ◽  
Hybrid Assemblies ◽  
Time Resolved Photoluminescence

We studied the photoluminescence and time-resolved photoluminescence from self-assembled bilayers of donor and acceptor nanoparticles (NPs) adsorbed on a quartz substrate through organic linkers. Charge and energy transfer processes within the assemblies were investigated as a function of the length of the dithiolated linker (DT) between the donors and acceptors. We found an unusual linker-length-dependency in the emission of the donors. This dependency may be explained by charge and energy transfer processes in the vertical direction (from the donors to the acceptors) that depend strongly on charge transfer processes occurring in the horizontal plane (within the monolayer of the acceptor), namely, parallel to the substrate.

scholarly journals 3D Reconstruction of Pedestrian Trajectory with Moving Direction Learning and Optimal Gait Recognition

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Binbin Wang ◽  
Tingli Su ◽  
Xuebo Jin ◽  
Jianlei Kong ◽  
Yuting Bai
Keyword(s):  
Learning Algorithm ◽  
Gait Recognition ◽  
Vertical Direction ◽  
Recognition Algorithm ◽  
Measurement Unit ◽  
Complex Environments ◽  
Position Change ◽  
Vertical Movements ◽  
Moving Direction ◽  
Optimal Gait

An inertial measurement unit-based pedestrian navigation system that relies on the intelligent learning algorithm is useful for various applications, especially under some severe conditions, such as the tracking of firefighters and miners. Due to the complexity of the indoor environment, signal occlusion problems could lead to the failure of certain positioning methods. In complex environments, such as those involving fire rescue and emergency rescue, the barometric altimeter fails because of the influence of air pressure and temperature. This paper used an optimal gait recognition algorithm to improve the accuracy of gait detection. Then a learning-based moving direction determination method was proposed. With the Kalman filter and a zero-velocity update algorithm, different gaits could be accurately recognized, such as going upstairs, downstairs, and walking flat. According to the recognition results, the position change in the vertical direction could be reasonably corrected. The obtained 3D trajectory involving both horizontal and vertical movements has shown that the accuracy is significantly improved in practical complex environments.

Theoretical Studies of Collision-induced Energy Transfer in Electronically Excited States

1990 ◽  
Vol 94 (11) ◽  
pp. 1253-1262 ◽  
Author(s):  
M. H. Alexander ◽  
A. Berning ◽  
A. Degli Esposti ◽  
A. Joerg ◽  
A. Kliesch ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Excited States ◽  
Theoretical Studies ◽  
Electronically Excited States ◽  
Electronically Excited

Deep Plane Facelift: An Evaluation of the High-SMAS versus Standard Incision Points

2018 ◽  
Vol 34 (06) ◽  
pp. 646-650
Author(s):  
Chiara Amodeo ◽  
Vishad Nabili ◽  
Gregory Keller ◽  
Jordan Sand
Keyword(s):  
Skin Flap ◽  
Vertical Direction ◽  
Senior Author ◽  
Entry Point ◽  
Face Lift ◽  
Vertical Movements ◽  
Plane Face ◽  
Superficial Musculoaponeurotic System ◽  
Entry Points ◽  
Tissue Movement

AbstractIn surgery of the aging face, operative adjustments of the superficial musculoaponeurotic system (SMAS) enhance facial contours. The senior author has observed that the standard deep plane face lift entry points on the SMAS do not provide as much tissue movement in a vertical direction as high-SMAS deep plane face lift entry points. In this study, tissue movement was measured comparing the conventional SMAS entry point with a high-SMAS entry point for deep plane face lifts. Institutional review board approval was obtained. Fourteen facelift patients were enrolled, 10 female and 4 male. Average age was 63.4 (50–81) years. Tissue movement at three points along the jaw line was measured intraoperatively. Standard SMAS entry point suspension resulted in average vertical movements of 6.4, 10.3, and 13.8 mm and average horizontal movements of 3.5, 5.7, and 6.5 mm. High-SMAS entry point resulted in average vertical movements of 11.8, 17.9, and 24.1 mm and average horizontal movements of 5.8, 9.8, and 9.9 mm. This resulted in a 77.3% increase (p = 0.03) in vertical movement and a 61.4% increase (p = 0.02) in horizontal movement with a high-SMAS entry compared with standard SMAS entry. The high-SMAS entry point for a deep plane facelift resulted in a significant increase in lift for both the horizontal and vertical vector on the facial skin flap when compared with the conventional entry.

Spatio-temporal variability of internal waves in the Caspian Sea

2020 ◽  
Author(s):  
Olga Lavrova ◽  
Andrey Kostianoy
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Internal Waves ◽  
Satellite Data ◽  
Caspian Sea ◽  
Bottom Topography ◽  
Sea Surface ◽  
Anthropogenic Factors ◽  
Landsat 8 ◽  
The Caspian Sea

&lt;p&gt;Internal waves (IWs) are an intrinsic feature of all density stratified water bodies: oceans, seas, lakes and reservoirs. IWs occur due to various causes. Among them are tides and inertial motions, variations in atmospheric pressure and wind, underwater earthquakes, water flows over bottom topography, anthropogenic factors, etc. In coastal areas of oceans and tidal seas, &amp;#160;IWs induced by tidal currents over shelf edge predominate. Such IWs are well-studied in multiple field, laboratory and numerical experiments. However, the data on IWs in non-tidal seas, such as the Black, Baltic and Caspian Seas, are scarce. Meanwhile, our multi-year satellite observations prove IWs to be quite a characteristic hydrophysical phenomenon of the Caspian Sea. The sea is considered non-tidal because tide height does not exceed 12 cm at the coastline. And yet surface manifestations of IWs are regularly observed in satellite data, both radar and visible. The goal of our study was to reveal spatial, seasonal and interannual variability of IW surface manifestations in the Caspian Sea in the periods of 1999-2012 and 2018-2019 from the analysis of satellite data. All available satellite radar and visible data were used, that is data from ERS1/2 SAR; Envisat ASAR; Sentinel-1A,1B SAR-C; Landsat-4,5 TM; Landsat-7 ETM+; Landsat-8 OLI; Sentinel-2A,2B MSI sensors. During the year, IWs were observed from the beginning of May to mid-September. In certain years, depending on hydrometeorological conditions, such as water heating, wind field, etc., no IWs could be seen in May or September. IWs regularly occur in the east of Middle Caspian and in the northeast of South Caspian. In North Caspian, due to its shallowness and absence of pronounced stratification, IWs are not generated, at least their surface signatures cannot be found in satellite data. In the west of the sea, IWs are scarcely observed, primarily at the beginning of the summer season. IW trains propagate toward the coast, their generation sites are mainly over the depths of 50-200 m.&lt;/p&gt;&lt;p&gt;According to the available data for the studied periods, the time of the first appearance of IW signatures differs significantly from year to year. For example, in 1999 and 2000 it happened only in July.&lt;/p&gt;&lt;p&gt;Since no in situ measurements were conducted in the sites of regular IW manifestations, an attempt&amp;#160; was made to establish the dependence of IW occurrence frequency&amp;#160; on seasonal and interannual variations of sea surface temperature, an indirect indicator of the depth of the diurnal or seasonal thermocline, that is where IW were generated. Sea surface temperature was also estimated from satellite data.&lt;/p&gt;&lt;p&gt;Another issue addressed in the work was the differentiation between the sea surface signatures of IWs in the atmosphere and the sea. The Caspian Sea is known for their close similarity in spatial characteristics.&lt;/p&gt;&lt;p&gt;The work was carried out with financial support of the Russian Science Foundation grant #19-77-20060.&amp;#160; Processing of satellite data was carried out by Center for Collective Use &amp;#8220;IKI-Monitoring&amp;#8221; with the use of &amp;#8220;See The Sea&amp;#8221; system, that was implemented in frame of Theme &amp;#8220;Monitoring&amp;#8221;, State register No. 01.20.0.2.00164.&lt;/p&gt;

Theoretical studies of energy transfer in disordered condensed media

1980 ◽  
Vol 72 (10) ◽  
pp. 5320-5332 ◽  
Author(s):  
A. Blumen ◽  
J. Klafter ◽  
R. Silbey
Keyword(s):  
Energy Transfer ◽  
Theoretical Studies ◽  
Condensed Media

A numerical investigation of solitary internal waves with trapped cores formed via shoaling

2002 ◽  
Vol 451 ◽  
pp. 109-144 ◽  
Author(s):  
KEVIN G. LAMB
Keyword(s):  
Internal Waves ◽  
Mixed Layer ◽  
Propagation Speed ◽  
Horizontal Velocity ◽  
Buoyancy Frequency ◽  
Surface Mixed Layer ◽  
Near Surface ◽  
Flow Limit ◽  
Wave Propagation Speed ◽  
Solitary Internal Waves

The formation of solitary internal waves with trapped cores via shoaling is investigated numerically. For density fields for which the buoyancy frequency increases monotonically towards the surface, sufficiently large solitary waves break as they shoal and form solitary-like waves with trapped fluid cores. Properties of large-amplitude waves are shown to be sensitive to the near-surface stratification. For the monotonic stratifications considered, waves with open streamlines are limited in amplitude by the breaking limit (maximum horizontal velocity equals wave propagation speed). When an exponential density stratification is modified to include a thin surface mixed layer, wave amplitudes are limited by the conjugate flow limit, in which case waves become long and horizontally uniform in the centre. The maximum horizontal velocity in the limiting wave is much less than the wave's propagation speed and as a consequence, waves with trapped cores are not formed in the presence of the surface mixed layer.

scholarly journals On the theory of long waves and bores

1914 ◽  
Vol 90 (619) ◽  
pp. 324-328 ◽  
Keyword(s):  
Steady Motion ◽  
Vertical Direction ◽  
Two Dimensions ◽  
Long Waves ◽  
Horizontal Velocity

In the theory of long waves in two dimensions, which we may suppose to be reduced to a "steady" motion, it is assumed that the length is so great in proportion to the depth of the water that the velocity in a vertical direction can be neglected, and that the horizontal velocity is uniform across each section of the canal. This, it should be observed, is perfectly distinct from any supposition as to the height of the wave. If l be the undisturbed depth, and h the elevation of the water at any point of the wave, u 0 , u the velocities corresponding to l , l + h respectively, we have, as the equation of continuity, u = lu 0 / l + h . (1) By the the principles of hydrodyamics, the increase of pressure due to retardation will be ½ ρ ( u 0 2 - u 2 ) = ρu 0 2 /2. 2 lh + h 2 /( l + h ) 2 . (2)

INTERNAL GRAVITY-SHEAR WAVES IN THE TROPOSPHERE: I. PHASE VELOCITIES

1966 ◽  
Vol 44 (10) ◽  
pp. 2259-2273 ◽  
Author(s):  
Keikichi Naito
Keyword(s):  
Internal Waves ◽  
Shear Waves ◽  
Horizontal Velocity ◽  
Long Wavelength ◽  
First Order ◽  
Phase Velocities ◽  
Air Density ◽  
Simple Models

The theory of internal gravity-shear waves in the troposphere is examined for two- and three-layer models of air density and horizontal velocity. It is shown that models having continuity in air density across the internal boundaries are not satisfactory for analysis involving first-order perturbations. The complexity of the analysis increases rapidly with the introduction of a gradient in the model density, and with additional layers in the model. The phase velocities of internal waves of wavelength between 100.m and 10 000 m are calculated for three simple models; the long-wavelength predictions agree favorably with observations by Gossard and Munk. No comparison is available for the shorter wavelengths.

Theoretical studies of energy transfer and reaction in H+H2O and H+D2O collisions

1993 ◽  
Vol 98 (6) ◽  
pp. 4644-4651 ◽  
Author(s):  
Kathleen Kudla ◽  
George C. Schatz
Keyword(s):  
Energy Transfer ◽  
Theoretical Studies
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