Jitka Janová

Crop planning optimization model: the validation and verification processes

Each optimization problem in the area of natural resources claims for a specific validation and verification (V&V) procedures which, for overwhelming majority of the models, have not been developed so far. In this paper we develop V&V procedures for the crop planning optimization models in agriculture when the randomness of harvests is considered and complex crop rotation restrictions must hold. We list the criteria for developing V&V processes in this particular case, discuss the restrictions given by the data availability and suggest the V&V procedures. To show its relevance, they are applied to recently constructed stochastic programming model aiming to serve as a decision support tool for crop plan optimization in South Moravian farm. We find that the model is verified and valid and if applied in practice—it thus offers a plausible alternative to standard decision making routine on farms which often leads to breaking the crop rotation rules.

Coupled rolling motion: a student project in non-holonomic mechanics

This paper presents an original undergraduate student project in theoretical mechanics: a demonstration of theory and experiment agreement inspired by a recently theoretically treated mechanical problem of coupled rolling motion of two cylinders. The problem of a mechanical system subjected to non-holonomic constraints is theoretically and numerically solved. Subsequently, the solution is quantitatively verified by a simple and inexpensive experiment, originally proposed and constructed by the authors. The comparison of results of the theoretical study with experimental output shows that there are instruments to directly verify rather abstract mathematical theories even on the undergraduate level. Moreover, combining the theoretical description of the problem with an appropriate laboratory experiment and computational procedures gives students a more complex view of the physical problem as a whole. This paper can be used by physics teachers on the undergraduate university level as an inspiration for an interesting student project. Moreover, the theoretical part of this paper itself can be used by interested intermediate students themselves as a good exercise in theoretical mechanics.

Coupled rolling motion: considering rolling friction in non-holonomic mechanics

This paper enlarges an undergraduate student project in non-holonomic mechanics (Janova et al 2009 Eur. J. Phys. 30 1257–69) by considering rolling friction. In the original problem of coupled rolling motion, the agreement of theory and experiment was demonstrated for the initial part of motion with rolling friction being neglected. As expected, the reality is that rolling friction plays a decisive role during the whole experiment. Extending the correspondence of the model to reality by considering rolling friction, in this paper it is demonstrated that the model satisfactorily explains not only the initial part but also the whole period of the motion observed. Together with the original problem, this paper is an interesting demonstration of the influence of rolling friction and its physical modelling for undergraduate physics education. It also demonstrates that a relatively simple theoretical background can be used for describing realistic situations in mechanics and for explaining experimental results. Moreover, this paper itself can be used by physics teachers as an interesting project in theoretical mechanics that may be solved both separately from and as a follow-up project to Janova et al (2009).

The streetboard rider: an appealing problem in non-holonomic mechanics

This paper enlarges the reservoir of solved tutor problems in non-holonomic mechanics at the undergraduate level of physics education. Unlike other, rather artificial, solved problems typically used, the streetboard-rider locomotion problem presented here represents an appealing contemporary real-world problem with interesting applications in a popular sport and in robotics. In this paper, the streetboard motion is discussed from the physical point of view. We show that the interesting snake-like motion performed by streetboard riders stems from its non-holonomic nature. The related non-holonomic constraints are derived and the problem of the mechanical system subjected to these non-holonomic constraints is solved using methods appropriate to the undergraduate university level. The analytical solution for the circular motion and the numerical solution for the general motion are obtained, the physical meaning of the derived constrained forces is investigated and the results are discussed with respect to observed streetboard-rider locomotion. The brief outline of the paper can be used as a demonstration example in non-holonomic mechanics lessons, while the paper itself establishes an original undergraduate computational student project in theoretical mechanics.

alfaDRA: A program for automatic elimination of variety self-proximities in alpha-design

Abstract When using alpha-design for plant variety testing under space restrictions, ex post design modifications must be implemented to prevent variety self-proximity on plots and, consequently, to prevent damage-induced loss of experimental information. This is done ad hoc for each experiment; the unsystematic modification is, however, commonly not only unable to resolve all existing proximities, but may introduce secondary undesired proximities. In this paper, a procedure is developed for the universal construction of modified alpha-design that covers all existing proximity constraints while keeping the efficiency level of the original design. Using extensive real data simulation, we validate the procedure and confirm high damage robustness of the modified designs. The procedure has been implemented as a Matlab function and is available as on-line supplement to the paper. The function enables to design the damage-robust experiments automatically using only standard computer equipment.

Optimal managing of forest structure using data simulated optimal control

We analyze the deterministic infinite time horizon optimal control model aimed to determine optimal areas forested by particular tree species in Drahanska highlands in the Czech Republic. Facing the limitations in original data available we suggest a simulation technique to generate valid full scope data and to estimate correct underlaying functions. The simulation procedure, based on the experts suggestions and comments, is described in detail and the economic interpretations of the assumptions made are provided. Subsequently, we develop the optimal control model given the nonlinear cost and revenue functions and find its analytical solution. The results obtained are discussed with respect to forestry practice and further application of our model. The presented approach intends to be a valid basement for further thorough study of related dynamical decision problems in the Czech forestry business.

Optimal Control for Forest Management in the Czech Republic

This contribution presents initial qualitative results and discussions when addressing the particular dynamic optimization problems in Czech forestry management. First, we analyze the deterministic infinite time horizon optimal control model aimed to determine the optimal paths for plantations of various mixed forests in the Morava region in the Czech Republic. Second, the problem of optimal dynamic path for the subsidy rates is established and its solution via optimal control using the simulated data is suggested. The at foremost aim of the presentation is to present the research topic itself and to discuss the optimization and solution techniques suggested.

Alternative Approaches for Assessing the European Countries Economic and Social Results

Abstract The European Union has been passing a complicated period over the last years. The EU economy lags behind its own development goals as well as, behind the results achieved by its economic partners and competitors – USA and Japan. Due to lower competitiveness in the international market environment, the persisting or even expanding problems on the domestic labor markets are evident. Many EU countries demonstrate relatively high unemployment which leads to weakening the income situation of households and strengthening the social tension in society. Particularly worrying is situation of young graduates and also people approaching retirement age and seniors. In context of such arguments, the strategy for perspective development of the EU – the strategic document Europe2020 – has been proposed. Its key objective is to strengthen the economic competitiveness of the European Union, its member countries and particularly the competitiveness of its firms. It is expected that the Europe 2020 objectives will create favorable environment for reducing the social tension across the EU countries and finally lead to the better life of majority of its citizens. All the EU2020 goals are difficult. To achieve them it is necessary to identify precisely the current positions of individual countries and their distances from these ambitious goals in order to select the optimal strategies to their fulfillment. Our paper aims to contribute to identification of the current competitiveness position of the EU and its member states in international market environment and to estimate the chances for achieving the EUROPE 2020 strategic goals.

Sustainable Development in the EU

The challenges of globalisation, technological progress and limited world resources that are typical of elevated consumption must be necessarily addressed in a manner that reflects both socio-economic and environmental problems. One relevant approach to these problems is represented by so-called sustainable economics. This approach cannot address traditional measures of economic performance such as GDP or GNP and requires a new methodology for the measurement of socio-economic activities in the environmental context. In this chapter, we present widely used indicators of sustainable development, namely, the Better Life Index, the Ecological Footprint, the Happy Planet Index, and the Environmental Performance Index. The content and appropriate uses of these indices in the EU countries are discussed, devoting special attention to the CEE countries. We also investigate relationships among those indices. Based on a quantitative analysis, we identify clusters of EU countries with similar levels of sustainable development. Furthermore, we classify the EU countries according to their effective use of natural resources relative to economic output.

Estimation of cost and revenue functions for reforestation system in Drahanska highlands

In this paper we are interesting in mathematical description of reforestation system in Drahanska highlands, which can be found in the Czech Republic. We estimate parameters of revenue and cost functions predefined according to formulation of underlying optimal control problem. Data related to wood processing economy are available in limited form only, because companies do not present their costs and profits in regular way. To cover overall situation in forestry management we employ simulation techniques, which provide data suitable for regression. Finally, shape and coefficients of cost and revenue functions are discussed for particular species.