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Number of results: 75
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Abstract

The development of technology and design of light management systems remains dynamic. Among all the benefits offered by these systems, the most valuable might definitely be the possibility of saving energy consumption. Knowing the value of energy savings is the key factor that users need to know before deciding to use a lighting management system (the type of light management system). For this purpose, it is useful to simulate the operation of the lighting control system, for example in the DIALux program. Such simulation helps evaluate potential savings in electricity consumption using the proposed lighting control system. In the DIALux program, it is possible to change the luminous flux value of luminaires. In such a case, it becomes possible to semi-simulate the light management system’s operation as we don’t receive actual information on reducing installed power of the lighting system during reduction of the luminous flux value of luminaires. This article shows what type of technical data are important to use for the DIALux program to properly and accurately simulate light management systems and to receive accurate data on energy saving. It also presents the results of photometrical and electric parameter measurements (Φ – luminous flux, P – power, PF – power factor, THDi – total harmonic distortion of current). The article discusses the power control characteristics obtained on the basis of these measurements and explores the source of differences between simulation of energy saving calculations and real measured energy savings. An existing lighting control system installed in an office reception area was used to compare calculations with the real value of energy consumption reduction. The impact of electronic power and control systems on electrical network parameters is also an important problem mentioned in this article. It also explores the effect of power regulation of LED luminaires and LED modules on the value of the power factor and total harmonic distortion (current) value (THDi).

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Authors and Affiliations

A. Wiśniewski
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Abstract

The present paper consists of two parts. The first part presents theoretical foundations of Msplit, estimation with reference to the previous author's paper (Wiśniewski, 2009). This time, some probabilistic assumptions are described in detail. A new quantity called f-information is also introduced to formulate the split potential in more general way. The main aim of this part of the paper is to generalize the target function of Msplit estimation that is the basis for a new formulation of the optimization problem. Such problem itself as well as its solution are presented in this part of the paper. The second part of the paper presents some special case of Mspli, estimation called squared Mspli, estimation (also with reference to the mentioned above paper of the author). That part presents a new solution and development in the theory of this version of M,plit estimation and some numerical examples that show properties of the method and its application scope.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

This part of the paper presents particular case of Msplit estimation called a squared Msplit estimation whose target function is based on convex squared functions. One can find here theoretical foundations and algorithm of the squared Msplit estimation as well as some numerical examples.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

Ice-cored moraines are the only accumulation forms of Antarctic ice-sheet in the contact zone with Bunger Hills. Their longiness ranges from 3.5 km to 250 m, they are from 300 m to 30 m wide and their elevation oscillates between 10 and 5 m. A thickness of moraimc cover which lags the ice-core is changeable in the limit of 1 m. A process of decay of ice-cores, leading to deformations of their moraines, plays a small part up to now. It is caused a dry climate, probably, which was not favorable for the release and the work of melted waters in a large scale. The weak separation of ice-cored moraines results from a small amount of morainic material transported to the front of ice-sheet, probably as the ice-sheet is almost motionless. The granulometric analysis of morainic sediments shows their bad segregation.

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Authors and Affiliations

Edward Wiśniewski
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Abstract

MP estimation is a method which concerns estimating of the location parameters when the probabilistic models of observations differ from the normal distributions in the kurtosis or asymmetry. The system of Pearson’s distributions is the probabilistic basis for the method. So far, such a method was applied and analyzed mostly for leptokurtic or mesokurtic distributions (Pearson’s distributions of types IV or VII), which predominate practical cases. The analyses of geodetic or astronomical observations show that we may also deal with sets which have moderate asymmetry or small negative excess kurtosis. Asymmetry might result from the influence of many small systematic errors, which were not eliminated during preprocessing of data. The excess kurtosis can be related with bigger or smaller (in relations to the Hagen hypothesis) frequency of occurrence of the elementary errors which are close to zero. Considering that fact, this paper focuses on the estimation with application of the Pearson platykurtic distributions of types I or II. The paper presents the solution of the corresponding optimization problem and its basic properties. Although platykurtic distributions are rare in practice, it was an interesting issue to find out what results can be provided by MP estimation in the case of such observation distributions. The numerical tests which are presented in the paper are rather limited; however, they allow us to draw some general conclusions.
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Authors and Affiliations

Zbigniew Wiśniewski
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Abstract

W artykule omówiono i poddano analizie dwa źródłowe teksty Henryka Elzenberga dotyczące zagadnienia zależności i niezależności etyki od obrazu świata oraz sporu o zależność etyki od religii. Temat dyskutowany był w Polsce od połowy lat pięćdziesiątych. W tekstach Elzenberga poddany został precyzyjnej analizie semantycznej i realnej. Jej wynik pokazuje, że treść ocen i norm pochodnych, ich realność i uzasadnienie są zależne od obrazu świata, w którym oceny i normy funkcjonują. Zależność od obrazu świata ulega natomiast ograniczeniu w sferze ocen i norm podstawowych. Podobnie jest z zależnością etyki od religii. Religijny obraz świata wielorako wpływa na zakres podmiotowy i przedmiotowy etyki, jej strukturę, na świadomość mocy obowiązującej i siłę motywacyjną, ale nie ma wpływu na logiczne uzasadnienie etyki. Etyka poza religijnym obrazem świata jest możliwa. Elzenberg wypowiada się z pozycji intuicjonisty w teorii poznania moralnego i jest perfekcjonistą w podążaniu za tym, co poznane moralnie i etycznie ugruntowane. Odrzuca jednak nieścisłe twierdzenie o niezależności etyki od obrazu świata i religii w ogóle.
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Authors and Affiliations

Ryszard Wiśniewski
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Abstract

Despite great technological progress scientists still are not capable of ascertaining how many species are there on Earth. Systematic studies are not only time-consuming, but sometimes also significantly impeded by constraints of available equipment. One of the methods for morphology evaluation, which is gradually more often used for taxonomical research is microcomputed tomography. It’s great spatial resolution and ability to gather volumetric data during single acquisition without sectioning specimen are properties especially useful in evaluation of small invertebrates. Nondestructive nature of micro-CT gives possibility to combine it with other imaging techniques even for single specimen. Moreover, in case of rare organisms studies it allows to collect full structural data without fracturing their bodies. Application of proper staining, exposure parameters or specific sample preparation significantly improves quality of performed studies. The following article presents summary of current trends and possibilities of microtomography in morphology studies of small invertebrates.
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Authors and Affiliations

Teresa Nesteruk
Łukasz Wiśniewski
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Abstract

The method that is proposed in the present paper is a special case of squared M split estimation. It concerns a direct estimation of the shift between the parameters of the functional models of geodetic observations. The shift in question may result from, for example, deformation of a geodetic network or other non-random disturbances that may influence coordinates of the network points. The paper also presents the example where such shift is identified with a phase displacement of a wave. The shift is estimated on the basis of wave observations and without any knowledge where such displacement took place. The estimates of the shift that are proposed in the paper are named Shift- M split estimators.
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Authors and Affiliations

Robert Duchnowski
Zbigniew Wiśniewski
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Abstract

Wild boars use natural feed such as ground cover for about half a year. In this work the contamination of boar muscles with caesium-137 and contamination of ground cover were compared. The level of caesium- 137 was measured by spectromertic method. Muscle samples from total 86 wild boars were collected just after Chernobyl accident (years I 986-1988 and in years I 998-1999). The results of the studies indicate that there is a relationship between radiocontamination of the environment as well as muscles of wild boars. It seems that animals at large can be good indicators of radiocontamination of the environment.
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Authors and Affiliations

Dariusz Jaworek
Jan Wiśniewski
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Abstract

In the paper presented have been the results of the analysis of effectiveness of operation of binary power plant consisting of combined two Clausius-Rankine cycles, namely the binary cycle with water as a working fluid in the upper cycle and organic substance as a working fluid in the lower cycle, as well as a single fluid component power plant operating also in line with the C-R cycle for superheated steam, with water as a working fluid. The influence of the parameters of superheated steam in the upper cycle has been assessed as well as the type of working fluid in the lower cycle. The results of calculations have been referred to the single-cycle classical steam power plant operating at the same parameters of superheated steam and the same mass flow rate of water circulating in both cycles. On the basis of accomplished analysis it has been shown that the binary power plant shows a greater power with respect to the reference power plant.
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Authors and Affiliations

Aleksander A. Stachel
Sławomir Wiśniewski
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Abstract

The article deals with the process of restoring life into the Elblag’s waterfront – located in the heart of the city, which is the Old Town with still forgotten Granary Island, both damaged by the second world war. The conclusions are inspired by publications about Elblag deriving from various periods, as well by international or students’ workshops. The author describes various considerations how to bring Granary Island into cultivation simultaneously with rebuilding Elblag’s Old Town, that derive from the conservation concept based on a new method named retroversion, how to create new panorama of the waterfront and what is the best way to integrate it with The Old Town, using Elblag River.

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Authors and Affiliations

Katarzyna Wiśniewska
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Abstract

Ursula K. Le Guin was an American writer, a master of science fiction and fantasy. She was the author of the famous Earthsea trilogy, in which magic remains the pivotal idea. In the novels, Le Guin links immense, yet dangerous, supernatural abilities with the idea of Equlibrium within realms, a principle that governs the universe. The paper is an attempt to elucidate how certain visions of life after death are constellated within Le Guin’s fantasy writings. Visibly inspired by Eastern mythologies and religious doctrines, the author does not steer clear from the vision rooted in Western traditions. The ongoing debate is an attempt at clarifying the universal concept of soul and mankind.
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Authors and Affiliations

Ewa Wiśniewska
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Abstract

The cognitive aim of this study is to point to the optimum number of local government units and the optimum boundaries of spatial units in Poland with the assumption of minimizing the cumulated theoretical travel time to all settlement units in the country. The methodological aim, in turn, is to present the use of the ArcGIS location-allocation tool for the purposes of delimitation processes as exemplified by administrative boundaries in Poland. The rationale for the implementation of this study is that number and the boundaries of units of all levels of Poland’s current territorial division are far from optimum in the light of minimization of accumulated theoretical travel time to all settlement units in the country. It may be concluded that it would be justifiable to increase the number of voivodships from the current number of 16 to 18. Besides it would be necessary to introduce modifications in relation to units with regional functions. In contrast, the number of districts and communes should be reduced. A continuation of this research may go in the direction of including analysis of public transport network in the research, creating in this way a multimodal set of network data. This would illustrate, apart from the potential itself resulting from the infrastructure, also the actually existing connections.
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Authors and Affiliations

Marta Borowska-Stefańska
Szymon Wiśniewski
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Abstract

The authors presented problems related to utilization of exhaust gases of the gas turbine unit for production of electricity in an Organic Rankine Cycle (ORC) power plant. The study shows that the thermal coupling of ORC cycle with a gas turbine unit improves the efficiency of the system. The undertaken analysis concerned four the so called "dry" organic fluids: benzene, cyclohexane, decane and toluene. The paper also presents the way how to improve thermal efficiency of Clausius-Rankine cycle in ORC power plant. This method depends on applying heat regeneration in ORC cycle, which involves pre-heating the organic fluid via vapour leaving the ORC turbine. As calculations showed this solution allows to considerably raise the thermal efficiency of Clausius-Rankine cycle.

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Authors and Affiliations

Sławomir Wiśniewski
Aleksandra Borsukiewicz-Gozdur
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Abstract

The paper presents studies of mathematical modelling in transonic flow through the first stage rotor of the axial compressor of homogenous and heterogeneous condensation. The condensation phenomena implemented into a commercial software is based on the classical theory of nucleation and molecular-kinetic droplet growth model. Model is validated against experimental studies available in the literature regarding the flow through the first stage of turbine compressor, i.e. the rotor37 transonic compressor benchmark test. The impact of air humidity and air contamination on the condensation process for different flow conditions is examined. The influence of latent heat release due to condensation exerts a significant impact on the flow structure, thus the analysis of the air humidity and contamination influence on the condensation is presented. The results presented indicate the non-negligible influence of air humidity on the flow structure in the transonic flow regime, thus it is recommended to take condensation phenomenon under consideration in high-velocity airflow simulations.

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Authors and Affiliations

Piotr Paweł Wiśniewski
Sławomir Dykas
Guojie Zhang
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Abstract

Distributed Denial of Service (DDoS) attacks constitute a major threat in the current Internet. These cyber-attacks aim to flood the target system with tailored malicious network traffic overwhelming its service capacity and consequently severely limiting legitimate users from using the service. This paper builds on the state-of-the-art AATAC algorithm (Autonomous Algorithm for Traffic Anomaly Detection) and provides a concept of a dedicated inline DDoS detector capable of real-time monitoring of network traffic and near-real-time anomaly detection.
The inline DDoS detector consists of two main elements: 1) inline probe(s) responsible for link-rate real-time processing and monitoring of network traffic with custom-built packet feature counters, and 2) an analyser that performs the near-real-time statistical analysis of these counters for anomaly detection. These elements communicate asynchronously via the Redis database, facilitating a wide range of deployment scenarios. The inline probes are based on COTS servers and utilise the DPDK framework (Data Plane Development Kit) and parallel packet processing on multiple CPU cores to achieve link rate traffic analysis, including tailored DPI analysis.
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Authors and Affiliations

Piotr Wiśniewski
1
Maciej Sosnowski
1
Wojciech Burakowski
1

  1. Warsaw University of Technology, Institute of Telecommunications

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