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Number of results: 9
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Abstract

In the paper, the extended finite element method (XFEM) is combined with a recovery procedure in the analysis of the discontinuous Poisson problem. The model considers the weak as well as the strong discontinuity. Computationally efficient low-order finite elements provided good convergence are used. The combination of the XFEM with a recovery procedure allows for optimal convergence rates in the gradient i.e. as the same order as the primary solution. The discontinuity is modelled independently of the finite element mesh using a step-enrichment and level set approach. The results show improved gradient prediction locally for the interface element and globally for the entire domain.
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Abstract

The paper proposes a procedure which enables to determine selected geometric and operating parameters for twin-fluid liquid-to-air atomisers with internal mixing. The presented approach assumes that in order to ensure proper operation of an atomiser it is necessary to design its structure and flow parameters in such a way so that the flow inside the mixing chamber has a dispersive character. In order to calculate a required exhaust cross-section for the analysed atomiser, conditions within the exhaust plane: pressure, density and outflow velocity were estimated. In order to determine diameter and number of orifices supplying the liquid to the mixing chamber of the investigated atomiser type, a multi-parameter analysis based on numerical fluid mechanics was performed. The final part of the paper presents selected results obtained from experimental stand measurements made on an atomiser designed according to the presented procedure.
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Abstract

One of the most significant changes in modern arbitration rules is the adoption of emergency arbitrator proceedings. These proceedings were introduced in order to provide a party in need of urgent interim measures before the constitution of an arbitral tribunal with an additional option besides going to state courts. In emergency arbitrator procedures such a party may seize an emergency arbitrator to grant the requested urgent relief. This article provides the Polish perspective on the effectiveness of emergency arbitrator proceedings, given that the Polish law is silent on the institution of emergency arbitrator and the possible recognition and enforcement of the decisions of an emergency arbitrator. The article analyses the Polish regulations on interim measures, together with their enforcement, by comparing the relationship, similarities and divergences between an arbitral tribunal, a state court, and an emergency arbitrator. This brings us to the conclusion that the existing legal framework as to the enforcement of interim measures issued by an arbitral tribunal provides a solid foundation for drawing an analogy to the recognition and enforcement of such orders granted by an emergency arbitrator. Thus, the provisions on enforcement of arbitral tribunal’s orders per analogiam allow for the recognition and enforcement of emergency arbitrators’ decisions on interim measures in Poland.
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Abstract

A new notion of a realization of transfer matrix of (P;Q; V)-cone-system for discrete-time linear systems is proposed. Necessary and sufficient conditions for the existence of the realizations are established. A procedure is proposed for computation of a realization of a given proper transfer matrix T(z) of (P;Q; V)-cone-system. It is shown that there exists a realization of T(z) of (P;Q; V)-cone-system if and only if there exists a positive realization of T(z) = V T(z)Q!1, where V;Q and P are non-singular matrices generating the cones V;Q and P respectively.
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Abstract

The majority of publications and monographs present investigations which concern exclusively twophase flows and particulary dispersed flows. However, in the chemical and petrochemical industries as well as in refineries or bioengineering, besides the apparatuses of two-phase flows there is an extremely broad region of three-phase systems, where the third phase constitutes the catalyst in form of solid particles (Duduković et al., 2002; Martinez et al., 1999) in either fixed bed or slurry reactors. Therefore, the goal of this study is to develop macroscopic, averaged balances of mass, momentum and energy for systems with three-phase flow. Local instantaneous conservation equations are derived, which constitute the basis of the method applied, and are averaged by means of Euler’s volumetric averaging procedure. In order to obtain the final balance equations which define the averaged variables of the system, the weighted averaging connected with Reynolds decomposition is used. The derived conservation equations of the trickle-bed reactor (mass, momentum and energy balance) and especially the interphase effects appearing in these equations are discussed in detail.
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Abstract

There may be circumstances where academic degrees or the title of professor are obtained deceitfully, i.e. in breach of copyrights or moral principles in science. Dishonesty in scientific research constitutes gross misconduct because it is executed in order to appropriate ideas, findings, collocations and theses of others, without accurate citation of the source. It also entails infringement of intellectual property rights. Scientific misconduct in ethical and legal aspect is explicit. It disqualifies the offender as a scientist. The unlawful act of obtaining an academic degree (Ph.D.) or the title of professor in such a deceitful manner, irrespective of how much time has passed, shall not make the resumption condition fall under the statute of limitations. Thus, it enables the reopening of procedures to deprive the person who deceitfully obtained an academic degree or title of this degree or title.
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Abstract

Electric energy meters are designed to account energy under sinusoidal and nonsinusoidal conditions, because both, old and new standards for energy meters require testing their accuracy under different conditions. The latest EN 50470 standard increases the range of meter testing under nonsinusoidal conditions, introducing new shapes of test signals such as the phase fired waveform or the burst fired waveform. This paper discusses calibration problems of electronic revenue energy meters for direct connection and for connection through current transformers, and it proposes a new calibration procedure which reproduces normal operating conditions better: three-phase configurations of measurement systems, load range during meter testing or shapes of test signals. Recently, modern Electrical Power Standards, also known as Power Calibrators, enable automatic testing of various types of electrical devices, including electricity meters in their normal operating conditions. This article presents examples of single and multi position fully automatic test systems, which employ Power/Energy Calibrator from Poland as the precision source with programmed waveforms of three phase voltages up to 560 V and currents up to 120 A conforming to EN 50470, or with random waveforms generated by PC software random wave generator. Measurement uncertainty of the energy meters under different nonsinusoidal conditions using a test system with reference to accuracy of the power calibrator or to the reference meter, are discussed. Comparative analysis of test results for different shapes of voltage and current signals is presented in the conclusions of this paper.
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Abstract

The notion of the normal transfer matrix and the notion of the structure decomposition of normal transfer matrix for 2D general model are introduced. Necessary and sufficient conditions for the existence of the structure decomposition of normal transfer matrix are established. A procedure for computation of the structure decomposition is proposed and illustrated by the numerical example. It is shown that the impulse response matrix of the normal model is independent of the polynomial part of its structure decomposition.
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Abstract

The main topic of this article is retroactive application of procedural criminal law. In this text the question will be posed – and answered – whether the application of a new procedural provision that entered into force in the course of an ongoing proceeding should in that proceeding be considered as retroactive and in what scope or/and under what conditions can such retroactivity be allowed for. As will be shown the solutions in national jurisdictions differ according to the common law – continental law states divide. This problem will be discussed in the light of a decision in the ICC Ruto and Sang case. In this case the ICC Appeals Chamber had to answer several questions pertaining to the temporal application of new procedural provisions. Firstly, the Chamber had to decide whether a general ban on the retroactive application of substantive law should also apply to procedural criminal law. Secondly, the ICC Appeals Chamber had to analyze the criteria according to which it would evaluate whether the change of rules of criminal procedure in the course of an ongoing trial was to be considered as having a retroactive effect, and whether the change in the rules of admission of evidence could be considered detrimental to the accused. Thirdly, it will be shown that the ICC Appeals Chamber has chosen the common law concept of “due process rights” rather than the idea of “intertemporal rules” known from the continental doctrine, and why it chose to do so.
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