Derivation of Three-Dimensional Radiation Stress Based on Lagrangian Solutions of Progressive Waves

AbstractA new approach has been proposed to derive the expressions for three-dimensional radiation stress using solutions of the pressure and velocity distributions and the coordinate transformation function that are derived from a Lagrangian description wherein the pressure is zero (relative to the atmospheric pressure) at the sea surface. Using this approach, analytical expressions of horizontal and vertical depth-dependent radiation stress are derived at a uniform depth and for a sloping bottom, respectively. The results of the depth integration of the expressions agree well with the theory of Longuet-Higgins and Stewart. In the case involving a sloping bottom, the radiation stress expressions from this study provide a better balance of the net momentum compared to those from previous studies.

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The Vertical Structure of the Surface Wave Radiation Stress for Circulation over a Sloping Bottom as Given by Thickness-Weighted-Mean Theory

Journal of Physical Oceanography ◽

10.1175/jpo-d-12-059.1 ◽

2013 ◽

Vol 43 (1) ◽

pp. 149-164 ◽

Cited By ~ 21

Author(s):

Hidenori Aiki ◽

Richard J. Greatbatch

Keyword(s):

Delta Function ◽

Sea Surface ◽

Wave Radiation ◽

Radiation Stress ◽

Weighted Mean ◽

Mean Velocity ◽

Pressure Term ◽

Wave Induced ◽

Stress Term ◽

Sloping Bottom

Abstract Previous attempts to derive the depth-dependent expression of the radiation stress have led to a debate concerning (i) the applicability of the Mellor approach to a sloping bottom, (ii) the introduction of the delta function at the mean sea surface in the later papers by Mellor, and (iii) a wave-induced pressure term derived in several recent studies. The authors use an equation system in vertically Lagrangian and horizontally Eulerian (VL) coordinates suitable for a concise treatment of the surface boundary and obtain an expression for the depth-dependent radiation stress that is consistent with the vertically integrated expression given by Longuet–Higgins and Stewart. Concerning (i)–(iii) above, the difficulty of handling a sloping bottom disappears when wave-averaged momentum equations in the VL coordinates are written for the development of (not the Lagrangian mean velocity but) the Eulerian mean velocity. There is also no delta function at the sea surface in the expression for the depth-dependent radiation stress. The connection between the wave-induced pressure term in the recent studies and the depth-dependent radiation stress term is easily shown by rewriting the pressure-based form stress term in the thickness-weighted-mean momentum equations as a velocity-based term that contains the time derivative of the pseudomomentum in the VL framework.

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Double Beam Spectrophotometer for Simultaneous Measurements of the Upwelling Sea Radiance and the Incident See Irradiance

Light & Engineering ◽

10.33383/2018-001 ◽

2019 ◽

pp. 105-110

Author(s):

Mikhail Yongon Lee ◽

Sergei V. Fedorov

Keyword(s):

Spectral Characteristics ◽

Sea Surface ◽

Input Port ◽

Silicon Photodiode ◽

New Approach ◽

Surface Irradiance ◽

Simultaneous Measurements ◽

Double Beam

The article describes the structure and the operation principle of the spectrophotometer developed on the basis of a compact rapid monochromator with one input port and two output ports and a radiometric unit where upwelling radiation radiance and sea surface irradiance channels are located. A new approach to measurements of spectral characteristics of upwelling radiation of sea based on combination of advantages of a double beam photometer with a photomultiplier and a directreading photometer with a highstability silicon photodiode for its absolute adjustment in energy units is implemented.

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Three-Dimensional Scattering of Internal Waves Off a Uniformly Sloping Bottom

10.21236/ada624739 ◽

2001 ◽

Author(s):

Rudolf C. Kloosterziel

Keyword(s):

Internal Waves ◽

Three Dimensional ◽

Sloping Bottom

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CALCULATION OF THE DEPENDENCE OF THE DISTANCE TO THE LOCATED OBJECT FROM THE CORNER POSITION OF THE VEHICLE LINE

Issues of radio electronics ◽

10.21778/2218-5453-2018-4-14-18 ◽

2018 ◽

pp. 14-18

Author(s):

V. V. Artyushenko ◽

A. V. Nikulin

Keyword(s):

Real Time ◽

Statistical Physics ◽

Angular Position ◽

Three Dimensional ◽

Line Of Sight ◽

Two Dimensional ◽

Radar Station ◽

Flight Mode ◽

Vector Algebra ◽

Analytical Expressions

To simulate echoes from the earth’s surface in the low flight mode, it is necessary to reproduce reliably the delayed reflected sounding signal of the radar in real time. For this, it is necessary to be able to calculate accurately and quickly the dependence of the distance to the object being measured from the angular position of the line of sight of the radar station. Obviously, the simplest expressions for calculating the range can be obtained for a segment or a plane. In the text of the article, analytical expressions for the calculation of range for two-dimensional and three-dimensional cases are obtained. Methods of statistical physics, vector algebra, and the theory of the radar of extended objects were used. Since the calculation of the dependence of the range of the object to the target from the angular position of the line of sight is carried out on the analytical expressions found in the paper, the result obtained is accurate, and due to the relative simplicity of the expressions obtained, the calculation does not require much time.

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Exploration of collagen cavitation based on peptide electrolysis

Scientific Reports ◽

10.1038/s41598-021-96533-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rui Zhai ◽

Hui Chen ◽

Zhihua Shan

Keyword(s):

Structural Changes ◽

Preparation Method ◽

Supporting Electrolyte ◽

Three Dimensional ◽

Anode Region ◽

New Approach ◽

New Material ◽

Animal Skin ◽

Exchange Membrane ◽

Material Preparation

AbstractElectrochemical modification of animal skin is a new material preparation method and new direction of research exploration. In this study, under the action of the electric field using NaCl as the supporting electrolyte, the effect of electrolysis on Glycyl-glycine(GlyGl), gelatin(Gel) and Three-dimensional rawhide collagen(3DC) were determined. The amino group of GlyGl is quickly eliminated within the anode region by electrolysis isolated by an anion exchange membrane. Using the same method, it was found that the molecular weight of Gel and the isoelectric point of the Gel decreased, and the viscosity and transparency of the Gel solution obviously changed. The electrolytic dissolution and structural changes of 3DC were further investigated. The results of TOC and TN showed that the organic matter in 3DC was dissolved by electrolysis, and the tissue cavitation was obvious. A new approach for the preparation of collagen-based multi-pore biomaterials by electrochemical method was explored.

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The contribution of Geomatics to increase safety and security in ports

Applied Geomatics ◽

10.1007/s12518-021-00374-3 ◽

2021 ◽

Author(s):

Maurizio Soldani

Keyword(s):

Atmospheric Pressure ◽

Research Team ◽

Environmental Parameters ◽

Sea Surface ◽

Port Security ◽

Process Data ◽

Water Quality Control ◽

Port Authorities ◽

Graphical Interfaces ◽

Port Areas

AbstractIn this paper, the advantages achievable from the use of two prototype systems that are being developed to increase safety and security in ports are shown. Both systems start by monitoring environmental parameters in harbors, and then process data acquired. The first system has been conceived to be helpful to port communities (port authorities, pilots) to optimize harbor waterside management (ship’s navigation and cargo, dock performances, boat moorings, refloating of stranded ships, water quality control). By monitoring and processing sea level and atmospheric pressure in port areas, it can help port communities, e.g., to choose the best time when a ship with a certain draft can enter or leave a harbor, or to plan the best route inside the basin for that vessel (port safety). The second system, instead, has been designed for port protection purposes: by monitoring and processing the Earth’s magnetic field below the sea surface in harbors (where the natural field is disturbed by a high artificial component), it is able to detect the possible presence of intruders (e.g., divers) swimming underwater in prohibited areas (port security). Here, the results of monitoring and processing activities of the two systems performed in Livorno and La Spezia harbors are shown (Italy). The processing procedures and the graphical interfaces of the systems are based on applications under development by the research team the author belongs to, by using C# and C++ languages; Matlab environment has been employed for simulations.

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A NEW APPROACH TO DYNAMIC FINITE-SIZE SCALING

International Journal of Modern Physics C ◽

10.1142/s012918310300508x ◽

2003 ◽

Vol 14 (07) ◽

pp. 945-954 ◽

Cited By ~ 1

Author(s):

MEHMET DİLAVER ◽

SEMRA GÜNDÜÇ ◽

MERAL AYDIN ◽

YİĞİT GÜNDÜÇ

Keyword(s):

Three Dimensional ◽

Finite Size ◽

Taylor Series Expansion ◽

Scaling Behavior ◽

Dynamic Scaling ◽

Finite Size Scaling ◽

New Approach ◽

Size Scaling ◽

Dynamic Exponent ◽

Good Agreement

In this work we have considered the Taylor series expansion of the dynamic scaling relation of the magnetization with respect to small initial magnetization values in order to study the dynamic scaling behavior of two- and three-dimensional Ising models. We have used the literature values of the critical exponents and of the new dynamic exponent x0 to observe the dynamic finite-size scaling behavior of the time evolution of the magnetization during early stages of the Monte Carlo simulation. For the three-dimensional Ising model we have also presented that this method opens the possibility of calculating z and x0 separately. Our results show good agreement with the literature values. Measurements done on lattices with different sizes seem to give very good scaling.

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Research on the Three-Dimensional Displaying of STL ASCII and Binary File

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.940.433 ◽

2014 ◽

Vol 940 ◽

pp. 433-436 ◽

Cited By ~ 1

Author(s):

Ying Zhang ◽

Xin Shi

Keyword(s):

Detailed Analysis ◽

Programming Language ◽

Coordinate Transformation ◽

Graphical Representation ◽

Three Dimensional ◽

File Format ◽

Binary File ◽

Stl File ◽

File Formats ◽

Three Dimensional Display

Based on the detailed analysis of the STL file format, VC++ 6.0 programming language was used to extract the STL ASCII and binary file information, at the same time, using the OpenGL triangle drawing technology for graphical representation of the STL file, with rendering functions such as material, coordinate transformation, lighting, et al, finally realizing the loading and three-dimensional display of STL ASCII and binary file formats.

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