scholarly journals SPATIAL DISTRIBUTION OF OVERTOPPING

2012 ◽  
Vol 1 (33) ◽  
pp. 63
Author(s):  
Anestis Lioutas ◽  
Gregory M. Smith ◽  
Henk Jan Verhagen
Keyword(s):  
Spatial Distribution ◽  
Physical Model ◽  
Computational Methods ◽  
Empirical Formula ◽  
Irregular Waves ◽  
Dominant Factor ◽  
Test Results ◽  
Wave Overtopping ◽  
Set Up

The scope of this research is to find an empirical formula to describe the distribution of wave overtopping in the region behind the crest. A physical model was set up in which irregular waves were generated. In order to find a formula which adequately describes the test observations, the influence of several parameters has been analysed. The proper determination of the crest freeboard, which is a dominant factor, has been investigated. Finally, the test results have been used to assess and compare the existing relevant computational methods.

scholarly journals Procedures and basic statistics to be used in magnitude control of equalisation reserves in Finland

1969 ◽  
Vol 5 (2) ◽  
pp. 227-238 ◽  
Author(s):  
Esa Hovinen
Keyword(s):  
Computational Methods ◽  
Maximum Amount ◽  
Insurance Companies ◽  
Poisson Function ◽  
Set Up ◽  
Random Fluctuations ◽  
Work Done ◽  
Work Up

This report aims at describing the procedures and statistics prepared for use in calculation of the limits of the equalisation reserves of Finnish insurance companies. The report is based on work done by a committee which the Federation of Finnish Insurance Companies set up in 1962. Its purpose was to collect and work up the necessary statistics and to develop computational methods to be used in practice for the computation of equalisation reserves. In one respect the work was initiated by the Supervisory Service, which prepared new and more precise regulations concerning the determination of limits of the above reserves.Because solvency problems of insurance companies have had great attention in recent years internationally, and the Finnish equalisation reserves are closely related to them, the theme may be sufficiently interesting to be presented once more setting out practical results. The solvency problem among other questions has been dealt with by Drs. Pesonen and Pentikäinen in former colloquia. This report can be considered as a continuation of Dr. Pesonen's paper “Magnitude Control of Technical Reserves in Finland” submitted to the Lucerne Colloquium and my paper “A Procedure to Compute Values of the Generalised Poisson Function” to the same colloquium.The principles and theoretical formulae to be used in computation of the limits for the equalisation reserves have already been stated in the papers of Drs. Pesonen and Pentikainen. Other technical reserves are not dealt with here.The equalisation reserve is roughly defined as that part of the technical reserves which exceeds the conventional premium reserve and the claims reserve and which secures the company's solvability against random fluctuations of claims and fluctuation of the basic probabilities of the claims. The equalisation reserve E must be greater than a minimum Emin from solvability reasons and, because of taxation, should not exceed a maximum amount Emax.

scholarly journals Estimate of Wave Overtopping Rate on Vertical Wall Using FUNWAVE-TVD Model

2021 ◽  
Vol 33 (6) ◽  
pp. 257-264
Author(s):  
Moon Su Kwak ◽  
Nobuhisa Kobayashi
Keyword(s):  
Numerical Calculation ◽  
Numerical Model ◽  
Calculation Result ◽  
Empirical Formula ◽  
Vertical Wall ◽  
Irregular Waves ◽  
Experimental Result ◽  
Wave Overtopping ◽  
Impulsive Wave ◽  
Numerical Calculation Result

This study established a numerical model capable of calculating the wave overtopping rate of coastal structures by nonlinear irregular waves using the FUNWAVE-TVD model, a fully nonlinear Boussinesq equation model. Here, a numerical model was established by coding the mean value approach equations of EurOtop (2018) and empirical formula by Goda (2009), and adding them as subroutines of the FUNWAVE-TVD model. The verification of the model was performed by numerically calculating the wave overtopping rate of nonlinear irregular waves on vertical wall structures and comparing them with the experimental results presented in EurOtop (2018). As a result of the verification, the numerical calculation result according to the EurOtop equation of this model was very well matched with the experimental result in all relative freeboard (Rc/Hmo) range under non-impulsive wave conditions, and the numerical calculation result of empirical formula was evaluated slightly smaller than the experimental result in Rc/Hmo < 0.8 and slightly larger than the experimental result in Rc/Hmo > 0.8. The results of this model were well represented in both the exponential curve and the power curve under impulsive wave conditions. Therefore, it was confirmed that this numerical model can simulate the wave overtopping rate caused by nonlinear irregular waves in an vertical wall structure.

Large-Scale Experiments of Wave-Overtopping Loads on Walls: Layer Thicknesses and Velocities

2018 ◽  
Author(s):  
Lorenzo Cappietti ◽  
Irene Simonetti ◽  
Andrea Esposito ◽  
Maximilian Streicher ◽  
Andreas Kortenhaus ◽  
...  
Keyword(s):  
Large Scale ◽  
Scale Validation ◽  
Irregular Waves ◽  
Scale Model ◽  
Small Scale ◽  
Wave Loads ◽  
Wave Overtopping ◽  
Large Scale Model ◽  
Vertical Walls ◽  
Set Up

Wave-Overtopping loads on vertical walls, such as those located on top of a dike, have been investigated in several small-scale experiments in the past. A large-scale validation for a mild foreshore situation is still missing. Hence the WALOWA (WAve LOads on WAlls) experimental campaign was carried out to address this topic. This paper, first presents a description of the large-scale model, the measurement set-up and the experimental methodologies, then it focuses on the layer thicknesses and velocities of the flows created on the promenade by the wave overtopping. A set of resistive wave gauges, ultrasonic distance sensors and velocimeters have been used to conduct these measurements. Preliminary data analysis and results, related to a 1000 irregular waves long test, are discussed. The momentum flux of these flows is studied and its implications, for the wave-overtopping loads acting on the vertical walls, are highlighted.

scholarly journals ON THE EFFECT OF CURRENT ON WAVE RUN-UP AND WAVE OVERTOPPING

2011 ◽  
Vol 1 (32) ◽  
pp. 13 ◽  
Author(s):  
Stefanie Lorke ◽  
Anja Brüning ◽  
Jentsje Van der Meer ◽  
Holger Schüttrumpf ◽  
Antje Bornschein ◽  
...  
Keyword(s):  
Shallow Water ◽  
Physical Model ◽  
Short Description ◽  
Test Results ◽  
Wave Overtopping ◽  
Oblique Wave ◽  
Physical Model Tests ◽  
Model Setup ◽  
Run Up ◽  
Sea Dikes

Intention of the project FlowDike-D is to quantify the impacts of current and wind on wave run-up and wave overtopping and to consider these processes in existing design formulae for estuarine, river and sea dikes. Physical model tests were carried out in the shallow water basin at DHI (Hørsholm/Denmark) for two different dike geometries (1:3 and 1:6 sloped dike). The paper introduces the model setup and test programme followed by a short description of the applied instrumentation. The test results for wave run-up and wave overtopping with oblique and non-oblique wave attack, but without current, correspond well with existing formulae from the EurOtop-Manual (2007). The influence of current parallel to the dike combined with different angles of wave attack on wave overtopping and wave run-up has been quantified. A distinction was made between wave attack with and against the current.

scholarly journals Oedometer tests - an aid in determination of the geological load history?

1996 ◽  
Vol 43 ◽  
pp. 41-50
Author(s):  
Grete Thorsen
Keyword(s):  
Effect Of Temperature ◽  
Test Results ◽  
Load History ◽  
Ice Caps ◽  
Preconsolidation Pressure ◽  
Significant Difference ◽  
Model Set ◽  
Set Up ◽  
Oedometer Tests

The paper describes the results of oedometer tests carried out with samples from Eemian fresh-water deposits and the methods used to determine the preconsolidation pressure from the test results. The influence of creep in the material on the apparent preconsolidation pressure is estimated from a model set up by Moust Jacobsen in 1992. The test results do not show any significant difference in the determined values of the overconsolidation ratio (OCR) for the samples from Hollerup and SolsØ, east and west of the main stationary line for the last ice sheet in Weichselian, respectively. The results, however, te11 nothing about the kind of actions, which has caused the overconsolidation. The determined OCR-values might be due to previous ice caps but a big difference in the two values from Solso indicates a considerable influence from other actions. The sediments from Hollerup and SolsØ are not identical, and the effect of temperature, chemical and biological processes on the apparent preconsolidation pressure has not been evaluated.

Respirometry for determination of the influents SS-concentration

1996 ◽  
Vol 33 (1) ◽  
pp. 311-323 ◽  
Author(s):  
A. Witteborg ◽  
A. van der Last ◽  
R. Hamming ◽  
I. Hemmers
Keyword(s):  
Experimental Design ◽  
Activated Sludge ◽  
Substrate Concentration ◽  
Full Scale ◽  
Activated Sludge Process ◽  
Respiration Rates ◽  
On Line ◽  
Large Measurement ◽  
Set Up

A method is presented for determining influent readily biodegradable substrate concentration (SS). The method is based on three different respiration rates, which can be measured with a continuous respiration meter which is operated in a cyclic way. Within the respiration meter nitrification is inhibited through the addition of ATU. Simulations were used to develop the respirometry set-up and decide upon the experimental design. The method was tested as part of a large measurement programme executed at a full-scale plant. The proposed respirometry set-up has been shown to be suitable for a semi-on-line determination of an influent SS which is fully based on the IAWQ #1 vision of the activated sludge process. The YH and the KS play a major role in the principle, and should be measured directly from the process.

Determination of trace concentrations of copper by FIA-FAAS after preconcentration on chelating sorbents

1989 ◽  
Vol 54 (7) ◽  
pp. 1785-1794 ◽  
Author(s):  
Vlastimil Kubáň ◽  
Josef Komárek ◽  
Zbyněk Zdráhal
Keyword(s):  
Sampling Frequency ◽  
Copper Determination ◽  
Flow Rates ◽  
Sample Injection ◽  
Injection Flow ◽  
Chelating Sorbents ◽  
Set Up ◽  
Trace Concentrations ◽  
Better Than

A FIA-FAAS apparatus containing a six-channel sorption equipment with five 3 x 26 mm microcolumns packed with Spheron Oxin 1 000, Ostsorb Oxin and Ostsorb DTTA was set up. Combined with sorption from 0.002M acetate buffer at pH 4.2 and desorption with 2M-HCl, copper can be determined at concentrations up to 100, 150 and 200 μg l-1, respectively. For sample and eluent flow rates of 5.0 and 4.0 ml min-1, respectively, and a sample injection time of 5 min, the limit of copper determination is LQ = 0.3 μg l-1, repeatability sr is better than 2% and recovery is R = 100 ± 2%. The enrichment factor is on the order of 102 and is a linear function of time (volume) of sample injection up to 5 min and of the sample injection flow rate up to 11 ml min-1 for Spheron Oxin 1 000 and Ostsorb DTTA. For times of sorption of 60 and 300 s, the sampling frequency is 70 and 35 samples/h, respectively. The parameters of the FIA-FAAS determination (acetylene-air flame) are comparable to or better than those achieved by ETA AAS. The method was applied to the determination of traces of copper in high-purity water.

Extra-Column Effects in Determination of Rate Parameters by the Chromatographic Method

1996 ◽  
Vol 61 (6) ◽  
pp. 844-855 ◽  
Author(s):  
Olga Šolcová ◽  
Petr Schneider
Keyword(s):  
Chromatographic Method ◽  
Dynamic Method ◽  
Axial Dispersion ◽  
Transport Parameters ◽  
Porous Particles ◽  
Loop Detector ◽  
Single Pellet ◽  
Set Up ◽  
Extra Column Effects

It was shown that the sampling loop, detector and connecting elements in the chromatographic set-up for determination of transport parameters by the dynamic method significantly influence the response peaks from columns packed with porous or nonporous particles. A method, based on the use of convolution theorem, was developed which can take these effects into account. The applicability of this method was demonstrated on the case of axial dispersion in a single-pellet-string column (SPSR) packed with nonporous particles. It is possible to handle also responses from columns packed with porous particles by a similar procedure.

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