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Publications from the year 2013
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Comparative Analysis of Two Polish Hyperbolic Systems AEGIR and JEMIOLUSZKA
- Sławomir Ambroziak
- Ryszard Katulski
- Jarosław Sadowski
- Jacek Stefański
- Wojciech Siwicki
Global Navigation Satellite System (GNSS) is seen by terrorists or hostile countries as a high value target. Volpe Center report contains the following statement: “During the course of its development for military use and more recent extension to many civilian uses, vulnerabilities of Global Navigation Satellite Systems (GNSS) – in the United States the Global Positioning System (GPS) – have become apparent. The vulnerabilities arise from natural, intentional, and unintentional sources. Increasing civilian and military reliance on GNSS brings with it a vital need to identify the critical vulnerabilities to civilian users, and to develop a plan to mitigate these vulnerabilities.” GNSS can also be targeted by more common criminals - computer hackers and virus writers. Therefore, there is a need for maintenance and continued development of independent radionavigation and radiolocation systems. This article will compare two Polish hyperbolic systems in terms of radio parameters, functionality and usability.
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Comparative conformance cases for monitoring multiple implementations of critical requirements
- Janusz Górski
- Aleksander Jarzębowicz
- Jakub Miler
The paper presents the concept and the mechanism of comparative conformance cases which support conformance monitoring in situations where a standard or other set of requirements are being implemented at multiple sites. The mechanism is enabled by NOR-STA services which implement the TRUST-IT methodology and are deployed in the cloud in accordance with the SaaS model. In the paper we introduce the concept of comparative conformance cases, explain the software services used to implement them and present a case study of monitoring the implementation of the EC Regulation No. 994/2010, re-lated to risk management of gas supply infrastructures across Europe.
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Comparative X-ray diffraction and Mössbauer spectroscopy studies of BiFeO3 ceramics prepared by conventional solid-state reaction and mechanical activation
- Elżbieta Jartych
- Agata Lisińska-Czekaj
- Dariusz Oleszak
- Dionizy Czekaj
The aim of this work was to prepare BiFeO3 by modified solid-state sintering and mechanical activation processes and to investigate the structure and hyperfine interactions of the material. X-ray diffraction and Mössbauer spectroscopy were applied as complementary methods. In the case of sintering, BiFeO3 phase was obtained from the mixture of precursors with 3 and 5 % excess of Bi2O3 during heating at 1023 K. Small amounts of impurities such as Bi2Fe4O9 and sillenite were recognized. In the case of mechanical activation, the milling of stoichiometric amounts of Bi2O3 and Fe2O3 followed by isothermal annealing at 973 K resulted in formation of the mixture of BiFeO3, Bi2Fe4O9, sillenite and hematite. After separate milling of individual Bi2O3 and Fe2O3 powders, mixing, further milling and thermal processing, the amount of desired BiFeO3 pure phase was significantly increased (from 70 to 90 %, as roughly estimated). From Mössbauer spectra, the hyperfine interaction parameters of the desired BiFeO3 compound, paramagnetic impurities of Bi2Fe4O9 and sillenite were determined. The main conclusion is that the lowest amount of impurities was obtained for BiFeO3 with 3 % excess of Bi2O3, which was sintered at 1023 K. However, in the case of mechanical activation, the pure phase formed at a temperature by 50 K lower as compared to solid-state sintering temperature. X-ray diffraction and Mössbauer spectroscopy revealed that for both sintered and mechanically activated BiFeO3 compounds, thermal treatment at elevated temperature led to a partial eliminating of the paramagnetic impurities.
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Comparison and Analysis of Service Selection Algorithms
- Paweł Kaczmarek
In Service Oriented Architecture, applications are developed by integration of existing services in order to reduce development cost and time. The approach, however, requires algorithms that select appropriate services out of available, alternative ones. The selection process may consider both optimalization requirements, such as maximalization of performance, and constraint requirements, such minimal security or maximum development cost. The selection problem has NP-hard computational complexity in a general case, which causes the necessity to use approximate algorithms. The paper compares existing algorithms and identifies typical algorithm characteristics. The algorithms are based on two main processing models: graph model using multiconstraint optimal path selection and combinatorial model using 0-1 multidimensional multichoice knapsack problem. Computational complexity and accuracy were considered in the analysis using both theoretical calculations and known experimental results. Algorithms use typically some simplifications during processing, which may cover either filtering of potential solutions or a simplified application model. Additionally, specific features of algorithms were identified, including: dynamic adaptation of service selection during execution and application of artificial intelligence methods.
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Comparison of heat transfer characteristics in surface cooling using microjets with water, ethanol and HFE7100 as test fluids
- Dariusz Mikielewicz
- Tomasz Muszyński
Accurate control of cooling parameters is required in ever wider range of technical applications. It is known that reducing the dimensions of the size of nozzle leads to an increase in the economy of cooling and improves its quality. Present study describes research related to the design and construction of the nozzles and microjet study, which may be applied in many technical applications such as in metallurgy, electronics, etc. Using liquids such as water, boiling is likely to occur when the surface temperature exceeds the coolant saturation temperature. Boiling is associated with large rates of heat transfer because of the latent heat of evaporation and because of the enhancement of the level of turbulence between the liquid and the solid surface, Garimella and Rice (1995). This enhancement is due to the mixing action associated with the cyclic nucleation, growth, and departure or collapse of vapour bubbles on the surface. In the case of flow boiling, such as boiling under impinging jets, the interaction between the bubble dynamics and the jet hydrodynamics has significant effect on the rate of heat transfer. The common approach used to determine the rate of boiling heat transfer is by using a set of empirical equations that correlate the value of the surface heat flux or the heat transfer coefficient with the fluid properties, surface conditions, and flow conditions The basis of microjet technology is to produce laminar jets which when impinging the surface have a very high kinetic energy at the stagnation point, Mikielewicz and Muszynski (2009), Mikielewicz et al (2011). Boundary layer is not formed in those conditions, while the area of film cooling has a very high turbulence resulting from a very high heat transfer coefficient. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm in width. The paper presents the investigation of a single water microjet cooling forming an evaporating liquid film on the impingement surface. Examined is the influence of liquid subcooling on the extent of the critical heat flux. Tests were conducted under steady state conditions. Developed also has been a theoretical model of surface cooling by evaporating microjet impinging in the stagnation point, where the highest heat transfer coefficient occurs.
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Comparison of induction motor bearing diagnostic test results through vibration and stator current measurement
- Tomasz Ciszewski
- Leon Swędrowski
The paper discusses results of tests performed by authors, related to the angine bearings diagnostic using vibration and stator current measurements. The paper contains the description of an automatic measurement system, developed for measurement of those harmonics and processing that to obtain bearing diagnostic information. System was tested on objects with intentionally made defects in bearings, results of this test was also shown in the paper.
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Comparison of single microjet cooling with water, ethanol and HFE7100 as test fluids
- Tomasz Muszyński
The paper presents the investigation of a single microjet cooling forming an thin liquid film on the impingement surface of specially designed rig. The basis of microjet technology is to produce laminar jets, which when impinging the surface have a very high kinetic energy at the stagnation point. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm in width. Examined is the influence of jet velocity and physical properties. Tests were conducted under steady state conditions, for three fluids namely water, ethanol and HFE7100. Simple empirical correlation has been developed describing Nusselt number on the cooled surface.
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Comparison of state feedback and PID control of pressurizer water level in nuclear power plant
- Mariusz Czapliński
- Paweł Sokólski
- Kazimierz Duzinkiewicz
- Robert Piotrowski
- Tomasz Adam Rutkowski
The pressurizer water level control system in nuclear power plant with pressurized water reactor (PWR) is responsible for coolant mass balance. The main control goal is to stabilize the water level at a reference value and to suppress the effect of time-varying disturbances (e.g. coolant leakage in primary circuit pipeline system). In the process of PWR power plant operation incorrect water level may disturb pressure control or may cause damage to electric heaters which could threaten plant security and stability. In modern reactors standard PID controllers are used to control water level in a pressurizer. This paper describesthe performance of state feedback integral controller (SFIC) with reduced-order Luenberger state observer designed for water level control in a pressurizer and compares it to the standard PID controller. All steps from modeling of a pressurizer through control design to implementation and simulation testing in Matlab/Simulink environment are detailed in the paper.
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Composite Materials Based on Polymer-Derived SiCN Ceramic and Disordered Hard Carbons as Anodes for Lithium-Ion Batteries
- Monika Wilamowska-Zawłocka
- Magdalena Graczyk-Zajac
- Ralf Riedel
New composite materials based on polymer-derived SiCN ceramics and hard carbons were studied in view of its application as anodes for lithium-ion batteries. Two kinds of composites were prepared by pyrolysis of the preceramic polysilazane (HTT1800, Clariant) at 1000 °C in Ar atmosphere mixed with hard carbons derived from potato starch (HC_PS) or with a hard carbon precursor, namely potato starch (PS), denoted as HTT/HC_PS and HTT/PS composites, respectively. Thermal gravimetric analysis suggests possible reactions between the preceramic polymer and the carbon precursor. The HTT/PS composites contain higher amount of oxygen and appear to be more homogeneous than that of the HTT/HC_PS composite. Raman analysis confirms the presence of highly disordered carbon in the composites by the appearance of the well-pronounced D band at 1347 cm−1. The materials are amorphous with a significant fraction of single graphene sheets as confirmed by X-ray diffraction. The HTT/PS composite exhibits a high-recovered capacity (434 mAh g−1 when charging with a current of 36 mA g−1) and outstanding cyclability for 400 cycles even at high current rates (90 mAh g−1 when charging with 3600 mA g−1). These properties make the composite a candidate anode material for high power energy devices.
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Computational modelling of concrete behavior under static and dynamic conditions
- Andrzej Tejchman-Konarzewski
- Ireneusz Marzec
W artykule zaproponowano wyniki obliczeń MES dla betonu podczas dynamicznego obciążenia. Przyjęto model sprężysto-plastyczno-lepki z nielokalnym osłabieniem. Obliczenia MES dla elementów betonowych pod obciążeniem dynamicznym o różnej prędkości obciążenia porównano bezpośrednio z doświadczeniami.
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Computer -Aided Local Energy Planning Using ALEP-PL Software
- Jerzy Buriak
The issue of energy system planning, including the planning of local energy systems, is critical, since it affects the security of energy supplies in communities, regions, and consequently the security of energy supply within the country. Energy planning is a complex process that requires integration of different goals i.e. improvement of energy efficiency, increase in the share of renewables in the energy balance and CO2} emission reduction. Integration of the requirements and objectives may be supported by the computer system tailored to collect and to process the data on energy and fuels consumption. This paper presents the assumptions made during the ALEP-PL computer software development. Advanced local energy planning is presented and the role of information systems in energy planning is discussed. In addition, the paper presents the advantages and disadvantages of existing computer applications supporting energy planning. The paper presents the current version of the ALEP-PL, which consists of database and web application and compares the application with existing solutions. The entity relationship diagram of ALEP-PL database is discussed. The main application interfaces are presented. The paper defines the main actors of the system and discusses the use case diagram. Examples of the use case analysis enabled the demonstration of the software functionality.
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Computer Supported Analysis of the Human Body Surface Area
- Grzegorz Redlarski
- Piotr Tojza
Recent scientific studies show the growing importance of the coefficients: BSA and TBSA, as an alternative to the widely used BMI. The relevant indicators are widely used in medicine, including such areas as: the treatment of burns, chemotherapy, dermatology and toxicology; as benchmarks when calculating doses of drugs and fluids. The particular problems concerning this subject are: the change of the reference parameter value which represents the patient's body weight, multiplicity and variety of applicable methods of calculating BSA and TBSA, as well as a the lack of computer systems supporting the performance of all analytical processes. Therefore, this article describes: the structure of the designed and developed computer system supporting the process of research and analysis for the identified state variables, and the study of the accuracy and reliability of the methods known from the literature and a proposal of imaging of the changes in individual coefficients, both in adults and children. For simulation studies 10 most commonly used methods were selected.
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Concentrations of alfa- and gamma- tocopherols in human breast milk during the first months of lactation and in infant formulas
- Dorota Martysiak-Żurowska
- Agnieszka Szlagatys-Sidorkiewicz
- Maciej Zagierski
The aim of this study was to determine the concentrations of alpha- and gamma-tocopherols in human breast milk samples from different periods of lactation and to compare them with tocopherol content in commercially available formulas for infants at corresponding ages. The study included 93 breast milk samples obtained on the 2nd (colostrum, n=17), 14th (n=30), 30th (n=27) and 90th day of lactation (n=19), along with 90 samples of commercially available initial and follow-on infant formulas. Concentrations of tocopherols were determined using normal-phase high-performance liquid chromatography. Depending on the stage of lactation, human breast milk contained 2.07–9.99 mg L-1 of alpha-tocopherol and 0.22–0.60 mg L-1 of gamma-tocopherol. Breast milk concentrations of alpha-tocopherol decreased with the time of lactation, while significant differences in gamma-tocopherol concentration were observed only between the 14th and 30th day of lactation. There was no significant correlation between the dietary intake of vitamin E and its estimated breast milk concentration, also in women who declared vitamin supplementation. Compared with colostrum, infant formulas were characterised by significantly lower concentrations of alpha-tocopherol and vitamin E. This finding indicates the need of additional vitamin E supplementation of bottle-fed infants during the initial 2–3 days of life
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Conception of Interactive Information and Decision Support System for Urban and Industrial Air Quality Management: Extension
- Cezary Orłowski
- Łukasz Szczygielski
- Krzysztof Bartosiewicz
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Conducted EMI Propagation Paths in DC-AC Hard Switching Converter
- Piotr Musznicki
In order to limit the electromagnetic interference (EMI) in power electronics devices, knowledge about the phenomena connected with EMI generation and propagation is necessary. This papers describes the propagation paths in the 3 phase voltage source inverter using wide-band simulation and laboratory test with the signal processing method Wiener filtering, where the transfer functions between voltage across switches and the perturbation are measured for different inverter states. Definition of the voltage source inverter switching states is presented for more accurate EMI analysis
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Confined granular flow in silos : experiments and numerical investigation
- Andrzej Tejchman-Konarzewski
W monografii opisano niektóre charakterystyczne zjawiska mające miejsce podczas przepływów silosowych materiałów sypkich. Wykonano badania doświadczalne oraz obliczenia numeryczne celem wyjaśnienia zjawisk. Doświadczenia wykonano w dużych i małych silosach. Obliczenia wykonano przy zastosowaniu metody elementów skończonych opartej na hipoplastycznym modelu konstytutywnym dla materiałów sypkich.
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Conjectured strong complementary-correlations tradeoff
- Andrzej Grudka
- Michał Horodecki
- Paweł Horodecki
- Ryszard Horodecki
- Waldemar Kłobus
- Łukasz Pankowski
We conjecture uncertainty relations that restrict correlations between the results of measurements performed by two separate parties on a shared quantum state. The first uncertainty relation bounds the sum of two mutual informations when one party measures a single observable and the other party measures one of two observables. The uncertainty relation does not follow from the Maassen-Uffink uncertainty relation and is much stronger than the Hall uncertainty relation derived from the latter. The second uncertainty relation bounds the sum of two mutual informations when each party measures one of two observables. We provide numerical evidence for the validity of the conjectured uncertainty relations, and we prove them for large classes of states and observables.
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Considerations of Adaptive Digital Communications in Underwater Acoustic Channel
- Iwona Kochańska
Down-link communication (DLC) and air transportable communication (ATAC) buoys as well as autonomous underwater vehicles (AUV) use acoustic links for gathering oceanographic data from underwater monitoring systems. The underwater channel propagation conditions are diverse in nature and require a special adaptive approach to the communication system design. The article presents a methodology for the communication systems design, combining modern radio standards experience, and hardware equipment to design and test the adaptive underwater data transmission systems. The testbed experiments should be preceded by the test being carried out under laboratory conditions using the underwater channel impulse responses collected at numerous measurement sessions in different reservoirs.
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Construction and development of IT Competence Centers - organizational structure
- Paweł Madej
The author presents the situation of the current units working between academic environment and business. the paper presents the possibility of using a dynamic structure to develop UCC.
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Construction and investigation of SO2 amperometric sensor with a solid polymer electrolyte membrane
- Anna Strzelczyk
- Grzegorz Jasiński
- Bogdan Chachulski
n this paper a sensor for detection of the sulphur dioxide based on three electrode cell configuration with a liquid electrolyte, a mercury sulphate reference electrode and a solid polymer electrolyte working electrode is presented. Working elec- trode was obtained by using Takenaka-Torikai chemical deposi- tion method by precipitation of Au particles into the pores of the Nafion membrane. Sensors characteristics measurements were performed in dynamic conditions during the gas flow. Responses of the sensor for the different concentration of SO 2 and NO 2 are presented. Sensitiv- ity and selectivity of the sensor have been determined.