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Silvia Kohnová, Ladislav Gaál, Tomáš Bacigál, Ján Szolgay, Kamila Hlavčová, Peter Valent, Juraj Parajka and Günter Blöschl

Abstract

The case study aims at selecting optimal bivariate copula models of the relationships between flood peaks and flood volumes from a regional perspective with a particular focus on flood generation processes. Besides the traditional approach that deals with the annual maxima of flood events, the current analysis also includes all independent flood events. The target region is located in the northwest of Austria; it consists of 69 small and mid-sized catchments. On the basis of the hourly runoff data from the period 1976- 2007, independent flood events were identified and assigned to one of the following three types of flood categories: synoptic floods, flash floods and snowmelt floods. Flood events in the given catchment are considered independent when they originate from different synoptic situations. Nine commonly-used copula types were fitted to the flood peak - flood volume pairs at each site. In this step, two databases were used: i) a process-based selection of all the independent flood events (three data samples at each catchment) and ii) the annual maxima of the flood peaks and the respective flood volumes regardless of the flood processes (one data sample per catchment). The goodness-of-fit of the nine copula types was examined on a regional basis throughout all the catchments. It was concluded that (1) the copula models for the flood processes are discernible locally; (2) the Clayton copula provides an unacceptable performance for all three processes as well as in the case of the annual maxima; (3) the rejection of the other copula types depends on the flood type and the sample size; (4) there are differences in the copulas with the best fits: for synoptic and flash floods, the best performance is associated with the extreme value copulas; for snowmelt floods, the Frank copula fits the best; while in the case of the annual maxima, no firm conclusion could be made due to the number of copulas with similarly acceptable overall performances. The general conclusion from this case study is that treating flood processes separately is beneficial; however, the usually available sample size in such real life studies is not sufficient to give generally valid recommendations for engineering design tasks.

Open access

Pattathal Vijayakumar Arun

References Bouckaert, R. R., Frank E., Hall M. A., Holmes G., Pfahringer B., Reutemann P. & Witten I. H. (2010). WEKA-Experiences with a Java Open-Source Project. Journal of Machine Learning Research, vol.11, 2533-2541. Durbha, S. S. & King R. L. (2005). Semantics-enabled framework for knowledge discovery from Earth observation data archives. IEEE Transaction on Geoscience and Remote Sensing, vol. 43(11), 2563-2572. Keim, D. A., Panse C. & Sips M. (2003). PixelMaps: A New Visual Data Mining Approach for

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Wojciech Drzewiecki

.R. (2004). Estimating replicability of classifier learning experiments. In Proceedings of the 21st International Conference on Machine Learning Banff, Canada, 2004. DOI: 10.1145/1015330.1015338 Bouckaert, R. R. and Frank, E. (2004). Evaluating the replicability of significance tests for comparing learning algorithms. In: D. Honghua, R. Srikant, and C. Zhang, (eds.), Advances in Knowledge Discovery and Data Mining, 8th Pacifi c-Asia Conference, PAKDD 2004, Sydney, Australia, May 26-28, 2004, Proceedings. Springer, 2004. DOI: 10.1007/b97861

Open access

Reports on Geodesy and Geoinformatics

(formerly: Reports on Geodesy); The Journal of Warsaw University of Technology

Open access

Adam Radzimski

support scheme focused on areas that reveal some characteristics of structural weakness. This is generally in line with the tradition of area-based interventions in Germany, which tended to put more emphasis on cohesion than on competitiveness ( Frank 2008 ). Thus, we could confirm previous observations that the German planning system is only marginally influenced by Anglo-Saxon neoliberalisation trends ( Waterhout, Othengrafen & Sykes 2013 ). Whether this also continues to be the case in the long term, or whether a certain convergence is about to take place, is likely

Open access

Ágnes Erőss

uncertainty of late twentieth-century postmodernism’ ( Young 2000 : 93). As E. Strakosch (2010 : 268) argues anti-monuments ‘Instead of presenting a simple story of triumph or martyrdom, confront the nation-state with its own crimes and exclusions’. Alternative forms of commemoration show great variety and have resulted in the mushrooming of different terms, like counter, non-traditional or non-monument. In their thorough article, Q. Stevens, K. A. Frank and R. Fazakerley (2012) introduce a system to bring more clarity to the discussions. According to their opinion, on

Open access

Justyna Kleszcz

the need for unfettered contact with nature free from any risks led to the revival, though in much modified form, of the idea of a sentimental connection between man and nature, which takes public form for all residents in a democratic manner, updating Ebenezer Howard’s visions of the Garden City ( Howard 1902 , 1946 ) or Frank L. Wright’s Usonia ( Wright 1932 ). This Arcadia will not arise, however, as a denouement of nodal elements, but as an idea of transforming entire urban structures. The urban farm in Brussels, where a local breed of cows grazes with a