In this work genetic programming is applied to the problem of generating maximum entanglement in multi-qubit systems of different structures. We provide quantum circuits that prepares multipartite entangled states in systems consisting of up to 8 qubits. We present results pertaining to the minimum size of a quantum circuit preparing a maximally entangled multi-qubit state in cases of reduced sets of quantum gates that correspond to spin chain quantum systems.

The complexity of power system phenomena challenges power system protection testing to obtain the required adequacy of the testing environment. Hardware-in-the-loop simulation in real-time substantially increases testing capabilities. However, there is still the question of the availability of commercial solutions. To address the challenges, a new hardware-in-the loop system has been designed and implemented utilizing the easily available Matlab/Simulink environment and Linux RT Preempt OS. The custom software part prepared for the presented system is based on the Matlab/Simulink s-function mechanism, Embedded Coder toolbox and Advantech biodaq library as the interface for the utilized I/O cards. The simulator’s real-time performance limits on Linux RT Preempt have been verified, and it was shown that its performance is sufficient to conduct successful tests of protection relays. Consequently, a simple power system protection relay testing example is provided, including a discussion of results. Finally, it has been proven that the presented system can be utilized as a simpler and more accessible hardware-in-the-loop testing alternative to commercial simulators.

New equivalent conditions of the asymptotical stability and stabilization of positive linear dynamical systems are investigated in this paper. The asymptotical stability of the positive linear systems means that there is a solution for linear inequalities systems. New necessary and sufficient conditions for the existence of solutions of the linear inequalities systems as well as the asymptotical stability of the linear dynamical systems are obtained. New conditions for the stabilization of the resultant closed-loop systems to be asymptotically stable and positive are also presented. Both the stability and the stabilization conditions can be easily checked by the so-called I-rank of a matrix and by solving linear programming (LP). The proposed LP has compact form and is ready to be implemented, which can be considered as an improvement of existing LP methods. Numerical examples are provided in the end to show the effectiveness of the proposed method.

This paper presents the design of digital controller for longitudinal aircraft model based on the Dynamic Contraction Method. The control task is formulated as a tracking problem of velocity and flight path angle, where decoupled output transients are accomplished in spite of incomplete information about varying parameters of the system and external disturbances. The design of digital controller based on the pseudo-continuous approach is presented, where the digital controller is the result of continuous-time controller discretization. A resulting output feedback controller has a simple form of a combination of low-order linear dynamical systems and a matrix whose entries depend nonlinearly on certain known process variables. Simulation results for an aircraft model confirm theoretical expectations.

The concept of `diversity' has been one of the main open issues in the field of multiple classifier systems. In this paper we address a facet of diversity related to its effectiveness for ensemble construction, namely, explicitly using diversity measures for ensemble construction techniques based on the kind of overproduce and choose strategy known as ensemble pruning. Such a strategy consists of selecting the (hopefully) more accurate subset of classifiers out of an original, larger ensemble. Whereas several existing pruning methods use some combination of individual classifiers' accuracy and diversity, it is still unclear whether such an evaluation function is better than the bare estimate of ensemble accuracy. We empirically investigate this issue by comparing two evaluation functions in the context of ensemble pruning: the estimate of ensemble accuracy, and its linear combination with several well-known diversity measures. This can also be viewed as using diversity as a regularizer, as suggested by some authors. To this aim we use a pruning method based on forward selection, since it allows a direct comparison between different evaluation functions. Experiments on thirty-seven benchmark data sets, four diversity measures and three base classifiers provide evidence that using diversity measures for ensemble pruning can be advantageous over using only ensemble accuracy, and that diversity measures can act as regularizers in this context.

The study presents the critical evaluation of existing drainage systems from legal, eco-nomical, environmental and technical viewpoints. Nearly 80% of agricultural land in Lithuania drained by underground drainage systems covers around 3 million hectares. The prevailing large scale drainage systems with a complex of engineering structures such as conducting ditches, drains and collectors, local roads, bridges or farm road-crossings, dikes, dams, water reservoirs, pumping stations for irrigation and for drainage need today an efficient management solution in a new economic situation. The detailed analysis of legal and economic instruments adopted in transferring the management responsibilities of drainage systems to users has been carried out. The study resulted in a number of practical contributions towards the amendments in the Law on Land Reclamation in Lithuania and the establishment of a system of indicators that would allow rationalisation of subsidy allocations for the maintenance and improvement of the drainage systems. These subsidies from the state budget make at the moment the largest share among the investment sources. The financial and in kind contribution of drainage users is permanently increasing as are the allocations of the structural funds for public projects. The EU pre-accession programme SAPARD started in 2000 has supported some investments in rural areas. Unfortunately, it did not support the drainage infrastructure properly. A critical review of previous measures allowed suggesting new actions within the framework of the actual support from EU structural funds.

The paper characterizes the status, trends and perspectives of irrigation in Poland after the reforms in agriculture and technology. Irrigation in Poland has supplemental character. It is used in short periods during the growing season and plays an important role in mitigating the effects of drought on crop production. Sub-irrigation from ditches is applied on permanent grasslands, sprin-kling – in field cultivation of arable crops, sprinkling and drip irrigation – in vegetable growing in open areas, micro-jets and drip irrigation systems – in orchards. Drip irrigation and micro-jets sys-tems are also applied in plant cultivation in greenhouses.

Under the economic conditions of Polish agriculture irrigation is often an unprofitable measure. The existing irrigation systems and facilities are only used to a small extent. After changes in the forms of ownership in agriculture, the large-area sprinkling systems were degraded. Small irrigation systems, mainly drip irrigation and micro-sprinkler irrigation, have recently become more common in private farms. Sub-irrigation systems are largely degraded and used only to a small extent if at all. In order to use these systems more effectively, it is necessary to reconstruct and modernize them. In many cases the factor preventing the use of irrigation systems is the deficit of water of required qual-ity and its availability. Besides unfavourable economic conditions, it is one of the main limitations in the development of irrigation in Poland.