scholarly journals Flood hazard in Slovenia and assessment of extreme design floods

2020 ◽  
pp. 43-59
Author(s):  
Matjaž Mikoš
Keyword(s):  
Empirical Equation ◽  
Flood Hazard ◽  
Monitoring Network ◽  
Empirical Equations ◽  
Hydraulic Modelling ◽  
Extreme Flows ◽  
Catchment Areas ◽  
High Dams ◽  
Hydrological Monitoring

Due to the lack of hydrological measurements in the torrential areas and smaller catchment areas of Slovenian rivers, in accordance with the European Floods Directive, we used an empirical equation to estimate the magnitude of a 500-year flood (Q500). In this paper, we critically evaluate the proposed empirical equations for estimating the Q500 discharge, as defined in the Slovenian Rules on the methodology for determining areas at risk of floods and related erosion of inland waters and the sea, and on the method of classifying land into risk classes. In this assessment, we use publicly available measured data from Slovenia’s hydrological monitoring network and data on extreme flows for selected Slovenian high dams, and thus compare the database with empirical equations for determining extreme flows in Europe and elsewhere in the world that are used for planning high dams. Although the reach of the Q500 flood line determines the area of residual flood danger, it makes sense to abandon the determination of extreme flows in Slovenia using empirical equations and move to a hydrological-hydraulic modelling system using modern software tools.

Establishment of a hydrological monitoring network in a tropical African catchment: An integrated participatory approach

2010 ◽  
Vol 35 (13-14) ◽  
pp. 648-656 ◽  
Author(s):  
M.C. Gomani ◽  
O. Dietrich ◽  
G. Lischeid ◽  
H. Mahoo ◽  
F. Mahay ◽  
...  
Keyword(s):  
Monitoring Network ◽  
Participatory Approach ◽  
Hydrological Monitoring

Empirical Equation for Determination of Alternate Bar Height

2019 ◽  
Vol 145 (11) ◽  
pp. 04019037
Author(s):  
Yunshuo Cheng ◽  
Ana Maria Ferreira da Silva
Keyword(s):  
Empirical Equation

scholarly journals Combining SAR and Optical Earth Observation with Hydraulic Simulation for Flood Mapping and Impact Assessment

2020 ◽  
Vol 12 (23) ◽  
pp. 3980
Author(s):  
Emmanouil Psomiadis ◽  
Michalis Diakakis ◽  
Konstantinos X. Soulis
Keyword(s):  
Impact Assessment ◽  
Temporal Dynamics ◽  
Flood Hazard ◽  
Recurrence Interval ◽  
Optical Data ◽  
Flood Event ◽  
Flood Events ◽  
Hydraulic Modelling ◽  
Flood Impact ◽  
Flood Characteristics

Timely mapping, measuring and impact assessment of flood events are crucial for the coordination of flood relief efforts and the elaboration of flood management and risk mitigation plans. However, this task is often challenging and time consuming with traditional land-based techniques. In this study, Sentinel-1 radar and Landsat images were utilized in collaboration with hydraulic modelling to obtain flood characteristics and land use/cover (LULC), and to assess flood impact in agricultural areas. Furthermore, indirect estimation of the recurrence interval of a flood event in a poorly gauged catchment was attempted by combining remote sensing (RS) and hydraulic modelling. To this end, a major flood event that occurred in Sperchios river catchment, in Central Greece, which is characterized by extensive farming activity was used as a case study. The synergistic usage of multitemporal RS products and hydraulic modelling has allowed the estimation of flood characteristics, such as extent, inundation depth, peak discharge, recurrence interval and inundation duration, providing valuable information for flood impact estimation and the future examination of flood hazard in poorly gauged basins. The capabilities of the ESA Sentinel-1 mission, which provides improved spatial and temporal analysis, allowing thus the mapping of the extent and temporal dynamics of flood events more accurately and independently from the weather conditions, were also highlighted. Both radar and optical data processing methods, i.e., thresholding, image differencing and water index calculation, provided similar and satisfactory results. Conclusively, multitemporal RS data and hydraulic modelling, with the selected techniques, can provide timely and useful flood observations during and right after flood disasters, applicable in a large part of the world where instrumental hydrological data are scarce and when an apace survey of the condition and information about temporal dynamics in the influenced region is crucial. However, future missions that will reduce further revisiting times will be valuable in this endeavor.

A Reconsideration of the Geometry Factor for the Standard and Profile Shifted Teeth

1989 ◽  
Vol 111 (3) ◽  
pp. 402-413 ◽  
Author(s):  
J. H. Kuang ◽  
Y. T. Yang
Keyword(s):  
Stress Concentration ◽  
Stress Distribution ◽  
Stress Concentration Factor ◽  
Empirical Equation ◽  
Design Parameters ◽  
Spur Gears ◽  
Geometry Factor ◽  
Gear Teeth ◽  
Semi Empirical

A semi-empirical equation for the determination of the stress concentration factor for spur gears is introduced. The effects of some design parameters such as fillet radii of rack cutters, teeth number, and profile shifting factor, on the stress distribution at the fillets of gear teeth are investigated. Values of the modified geometry factors for the standard and profile shifted teeth are also derived. It is hoped that the present investigation may yield a more accurate prediction of the localized stresses at tooth fillets than the results thus far available.

Empirical Formulae for the Determination of Stress Curves

1955 ◽  
Vol 59 (533) ◽  
pp. 362-364
Author(s):  
E. Voce
Keyword(s):  
Strain Hardening ◽  
Exponential Function ◽  
Threshold Stress ◽  
Empirical Equations ◽  
Hardening Process ◽  
Subsequent Deformation

The Paper by A.C.Nicholls in the October 1954 Journal (p. 724) describes two empirical equations neither of which possesses the first essential of an acceptable strain hardening function, namely that the stress attained in a preliminary straining operation shall become explicitly the threshold stress at which subsequent deformation begins. Eight years of study and the analysis of hundreds of published curves have convinced me that the exponential function put forward in 1948 faithfully reflects the strain hardening process. Far from being empirical, it can readily be deduced from a few simple and credible assumptions, and has counterparts in many branches of physics.

Determination of Suction Forces and Moment on Parallel Manoeuvring Vessels for a Future Control System

2011 ◽  
Vol 180 ◽  
pp. 281-287 ◽  
Author(s):  
Witold Gierusz ◽  
Anna Waszkiel
Keyword(s):  
Control System ◽  
Pressure Distribution ◽  
Working Conditions ◽  
Empirical Equations ◽  
Cfd Simulations ◽  
Passenger Car ◽  
Computer Based ◽  
Semi Empirical

Vessels moving on parallel courses on the border of two mediums interact together. Ship to ship interactions are caused by irregular pressure distribution around the hull. Higher velocity of the fluid between hulls causes formation of the decreased pressure amidships. This is the base of suction forces and moments generation. Analytical computations and computer based CFD simulations were carried out on the basis of 3DOF models of two training ships - VLCC and Passenger Car Ferry. The results of both methods are comparable. Therefore the analytical semi-empirical equations can be implemented in a future control system, which requires ship to ship interactions estimations to ensure proper working conditions.

DETERMINATION OF DIELECTRIC CONSTANT IN BINARY ORGANIC SYSTEMS

1960 ◽  
Vol 38 (9) ◽  
pp. 1606-1616 ◽  
Author(s):  
C. G. Miller ◽  
O. Maass
Keyword(s):  
Binary Systems ◽  
Isopropyl Alcohol ◽  
Dielectric Constants ◽  
Empirical Equations ◽  
Absolute Accuracy ◽  
Accurate Data ◽  
Organic Systems ◽  
Benzene Toluene ◽  
Made In

Measurements of the dielectric constants of binary systems have been made; hexane, benzene, toluene, acetone, isopropyl alcohol, and nitrobenzene have been used two at a time. It was the purpose to obtain accurate data for the dielectric constants for the 15 systems over the whole range of concentrations from 0 to 100%, with the absolute accuracy of 0.1%. It is claimed that the relative accuracy is of this order. From the data obtained regularities have been found which are expressed in the form of empirical equations which summarize the data. Tentative suggestions regarding theoretical conclusions are made in a number of cases.

Sign in / Sign up

Export Citation Format

Share Document