Efficient methods of automatic calibration for rainfall-runoff modelling in the Floreon+ system

Calibration of rainfall-runoff model parameters is an inseparable part of hydrological simulations. To achieve more accurate results of these simulations, it is necessary to implement an efficient calibration method that provides sufficient refinement of the model parameters in a reasonable time frame. In order to perform the calibration repeatedly for large amount of data and provide results of calibrated model simulations for the flood warning process in a short time, the method also has to be automated. In this paper, several local and global optimization methods are tested for their efficiency. The main goal is to identify the most accurate method for the calibration process that provides accurate results in an operational time frame (typically less than 1 hour) to be used in the flood prediction Floreon(+) system. All calibrations were performed on the measured data during the rainfall events in 2010 in the Moravian-Silesian region (Czech Republic) using our in-house rainfall-runoff model.Web of Science27441339

Precision-Aware application execution for Energy-optimization in HPC node system

Power consumption is a critical consideration in high performance computing systems and it is becoming the limiting factor to build and operate Petascale and Exascale systems. When studying the power consumption of existing systems running HPC workloads, we find that power, energy and performance are closely related which leads to the possibility to optimize energy consumption without sacrificing (much or at all) the performance. In this paper, we propose a HPC system running with a GNU/Linux OS and a Real Time Resource Manager (RTRM) that is aware and monitors the healthy of the platform. On the system, an application for disaster management runs. The application can run with different QoS depending on the situation. We defined two main situations. Normal execution, when there is no risk of a disaster, even though we still have to run the system to look ahead in the near future if the situation changes suddenly. In the second scenario, the possibilities for a disaster are very high. Then the allocation of more resources for improving the precision and the human decision has to be taken into account. The paper shows that at design time, it is possible to describe different optimal points that are going to be used at runtime by the RTOS with the application. This environment helps to the system that must run 24/7 in saving energy with the trade-off of losing precision. The paper shows a model execution which can improve the precision of results by 65% in average by increasing the number of iterations from 1e3 to 1e4. This also produces one order of magnitude longer execution time which leads to the need to use a multi-node solution. The optimal trade-off between precision vs. execution time is computed by the RTOS with the time overhead less than 10% against a native execution

Automatické simulace podnikových procesů

Import 23/07/2015Automatic simulations of business processes are able to provide various performance indicators that can be used for validating and improving the process and better planning of future projects based on the simulated process. This thesis describes one of the semi-formal methods used for business process modelling, simulation and enactment called the BPM Method, formalizes the behavioural model of this method and extends it with stochastic properties and mechanics that are needed to perform automatic simulation experiments. These extensions also simulate the availability and utilization of human resources in the process which can be used in identifying lack or abundance of workers in the process and thus help to lower waiting times for unavailable resources and achieve ideal utilization of resources. But every human resource is unique and has specific skills, behaviour and competencies that he uses to do his job and this influences his suitability to perform specific activities and also productivity of the resource when performing these activities. A method for evaluating human resources in the process is presented and used to allocate resources to their appropriate activities based on their competencies. Several allocation strategies, that benefit from the productivity evaluation, are considered for this allocation and their results are compared. Aside from allocating resources during automatic simulations, the proposed method can also be used for suggesting training topics for workers in the organization or to provide a specification for the hiring process.Automatické simulace podnikových procesů jsou schopny poskytnout výkonnostní indikátory, které mohou být použity k ověření a vylepšení procesu a k lepšímu rozplánování budoucích projektů založených na simulovaném procesu. Tato práce popisuje jednu ze semi-formálních metod nazývanou Metoda BPM, která slouží k modelování podnikových procesů a jejich simulaci, a formalizuje model chování této metody. Tento model je dále rozšířen o stochastické vlastnosti a další mechanismy potřebné k provádění automatických simulací. Tato rozšíření také simulují dostupnost a vytíženost lidských zdrojů v procesu a mohou tak odhalit nadbytek nebo nedostatek pracovníků v procesu. Na základě těchto informací je možné snížit doby čekání procesu na právě nedostupné zdroje a dosáhnout lepší alokace pracovníků v procesu. Každý lidský zdroj v procesu je ale unikátní a má specifické dovednosti, vlastnosti a kompetence, které používá při své práci. Tyto kompetence ovlivňují schopnosti tohoto pracovníka provádět jednotlivé aktivity v procesu včetně jeho produktivity při vykonávání těchto aktivit. Tato práce popisuje metodu pro vyhodnocení lidských zdrojů na základě jejich kompetencí a požadavků aktivit v procesu. Současně uvádí několik alokačních strategií, které využívají tohoto vyhodnocení, aby bylo při simulacích možné vybrat aktuálně nejvhodnějšího pracovníka. Kromě přidělování lidských zdrojů v automatických simulacích může být tato metoda použita i pro podporu rozhodování v otázkách školení zaměstnanců a v procesu zaměstnávání nových pracovníků.Prezenční460 - Katedra informatikyvyhově

Redakční systém

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta elektrotechniky a informatiky. Katedra (456) informatik

Analýza a návrh systému řízení lidských zdrojů

Import 07/06/2007Prezenční456 - Katedra informatik

Automatic allocation of resources in software process simulations using their capability and productivity

Software processes are very dependent on human behaviour, creativity and productivity. Business process management (BPM) simulation models are trying to model these properties to provide more precise information about the progress and parameters of the process. This paper describes a method for specifying competencies of resources in the process using competency models. These competencies are used to simulate human resource capability and productivity that influences the duration and allocation of resources to activities in the process. Different allocation strategies are based on this capability and productivity model to determine which resources should be allocated during automatic simulations. This method is then integrated into the BPM method simulation environment that is used to compare these allocation strategies in software process simulations for a middle-sized software development company.Web of Science10323622

Uncertainty modelling in Rainfall-Runoff simulations based on parallel Monte Carlo method

This article describes statistical evaluation of the computational model for precipitation forecast and proposes a method for uncertainty modelling of rainfall-runoff models in the Floreon+ system based on this evaluation. The Monte-Carlo simulation method is used for estimating possible river discharge and provides several confidence intervals that can support the decisions in operational disaster management. Experiments with other parameters of the model and their influence on final river discharge are also discussed.Web of Science25328626

Exploiting Big Earth Data from Space – First Experiences with the TimeScan Processing Chain

The European Sentinel missions and the latest generation of the United States Landsat satellites provide new opportunities for global environmental monitoring. They acquire imagery at spatial resolutions between 10 and 60 m in a temporal and spatial coverage that could before only be realized on the basis of lower resolution Earth observation data (>250 m). However, images gathered by these modern missions rapidly add up to data volume that can no longer be handled with standard work stations and software solutions. Hence, this contribution introduces the TimeScan concept which combines pre-existing tools to an exemplary modular pipeline for the flexible and scalable processing of massive image data collections on a variety of (private or public) computing clusters. The TimeScan framework covers solutions for data access to arbitrary mission archives (with different data provisioning policies) and data ingestion into a processing environment EO2Data module), mission specific pre-processing of multi-temporal data collections (Data2TimeS module), and the generation of a final TimeScan baseline product (TimeS2Stats module) providing a spectrally and temporally harmonized representation of the observed surfaces. Technically, a TimeScan layer aggregates the information content of hundreds or thousands of single images available for the area and time period of interest (i.e. up to hundreds of TBs or even PBs of data) into a higher level product with significantly reduced volume. In first test, the TimeScan pipeline has been used to process a global coverage of 452,799 multispectral Landsat–8 scenes acquired from 2013 to 2015, a global data-set of 25,550 Envisat ASAR radar images collected 2010–2012, and regional Sentinel–1 and Sentinel–2 collections of ∼1500 images acquired from 2014 to 2016. The resulting TimeScan products have already been successfully used in various studies related to the large-scale monitoring of environmental processes and their temporal dynamics