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Search results for: FOUR LEVEL CONVERTER
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Compact Dual-Polarized Corrugated Horn Antenna for Satellite Communications
PublicationIn this paper, a structure and design procedure of a novel compact dual-polarized corrugated horn antenna with high gain and a stable phase center for satellite communication is presented. The antenna incorporates an Ortho-Mode Transducer (OMT), a mode converter, and a corrugated structure. The compact OMT section is designed to be fed by standard WR-75 waveguides. The proposed compact design utilizes only ten corrugated slots...
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Możliwości integracji projektów sztuki nowych mediów w procesy odnowy przestrzeni miejskiej
PublicationZadaniem badawczym podjętym w rozprawie było wykazanie możliwość integracji projektów sztuki nowych mediów w procesy odnowy przestrzeni miejskiej. Wyodrębniono cztery etapy procesów odnowy miast: diagnozę, planowanie, realizację oraz ewaluację. Wskazano, że na etapie diagnozy sztuka nowych mediów może między innymi wspierać proces zbierania i wizualizacji danych, informować mieszkańców o stanie środowiska miejskiego. Na etapie...
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Speed sensorless induction motor drive with predictive current controller
PublicationToday, speed sensorless modes of operation are becoming standard solutions in the area of electric drives. This paper presents a speed sensorless control system of an induction motor with a predictive current controller. A closed-loop estimation system with robustness against motor parameter variation is used for the control approach. The proposed algorithm has been implemented using field-programmable gate arrays (FPGAs) and a...
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Low current transformer utilizing Co-based amorphous alloys
PublicationMetal oxide surge arresters have been widely used for protection of power system networks against overvoltages due to atmospheric discharges or malfunction of devices connected to the network. During its operation a surge arrester structure is degradated, what can be observed as an increase of a surge arrester leakage current. Paper presents an implementation of a new, high-permeability, Co64Fe4Ni1Si15B14 amorphous alloy as a current...
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Low Current Transformer Utilizing Co-Based Amorphous Alloys
PublicationMetal oxide surge arresters have been widely used for protection of power system networks against overvoltages due to atmospheric discharges or malfunction of devices connected to the network. During its operation a surge arrester structure is degradated, what can be observed as an increase of a surge arrester leakage current. Paper presents an implementation of a new, high-permeability, Co64Fe4Ni1Si15B14 amorphous alloy as a current...
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Modeling of a Quasi-Resonant DC Link Inverter Dedicated to Common-Mode Voltage and Ground Current Reduction
PublicationIn this paper, the modeling methodology of the AC drive system with a Parallel Quasi-Resonant DC Link Inverter (PQRDCLI) is described. A presented modeling approach is an attractive tool used for the effective evaluation of a common-mode (CM) voltage and grounds current reduction methods. Designed models of inverter, induction machine (IM), and cable are simple, thus the methods for parameter extraction are not complicated. Verification...
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Practice implementation of operational level agreement
PublicationThe paper concerns practical implementation of the Operational Level Agreement (OLA) compared to the Service Level Agreement (SLA).
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Microstrip four-port circulator using a ferrite coupled line section
PublicationThis paper describes an alternative configuration of a four-port circulator realized in a microstrip ferrite coupled line technology. The proposed fully planar device employs two three-port circulators consisting of a ferrite coupled line junction and T junction. Both circulators are connected through the same arm, hence, the problem of anti-parallel magnetization met in this type of circulators is avoided without the increase...
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Theory and implementation of a virtualisation level Future Internet defence in depth architecture
PublicationAn EU Future Internet Engineering project currently underway in Poland defines three parallel internets (PIs). The emerging IIP system (IIPS, abbreviating the project’s Polish name), has a four-level architecture, with level 2 responsible for creation of virtual resources of the PIs. This paper proposes a three-tier security architecture to address level 2 threats of unauthorised traffic injection and IIPS traffic manipulation...
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Power electronic transformer based on cascaded H-bridge converter
PublicationIn this paper the control strategy of power electronic transformer (PET) is proposed. The analyzed structure of PET uses two seven-level cascaded H-bridge (CHB) rectifiers. The electrical power of PET is transferred between DC-links of CHB converters using dual-active-bridges (DABs) and low voltage high frequency transformers. The roposed solution allows for controlling the active and reactive power with a low level of harmonic...
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Determining required safety integrity level
PublicationOne of the most important stage of technical system functional safety analysis is defining the safety-related functions as well as determining safety integrity level (SIL) for each defined function. A properly carried out hazard identyfication process is the necessary condition for correct definition of the safety-related functions. Determining the safety integrity level (SIL) is based on risk assessment taking into account risk...
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Spatial planning on regional level
PublicationPolish spatial planning results from typical for countries of Central and Eastern Europe transition . They have undergone the transformation from decentralized management system based on the dominance of state to the system of representative democracy, based on self-government administration; also territorial on regional level.
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Photovoltaic Maximum Power Point Technique based on Incremental Conductance (INCON) control algorithm
PublicationMaximum output power status can significantly improve the deployment rate of solar energy system. In order to get the maximum power output, issue of tracking maximum power point (MPP), reduced harmonics around MPP and improve efficiency of the solar power energy system, this paper presents the improved maximum power point tracking (MPPT) control...
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A CMOS Pixel With Embedded ADC, Digital CDS and Gain Correction Capability for Massively Parallel Imaging Array
PublicationIn the paper, a CMOS pixel has been proposed for imaging arrays with massively parallel image acquisition and simultaneous compensation of dark signal nonuniformity (DSNU) as well as photoresponse nonuniformity (PRNU). In our solution the pixel contains all necessary functional blocks: a photosensor and an analog-to-digital converter (ADC) with built-in correlated double sampling (CDS) integrated together. It is implemented in...
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Canonical switched capacitor converters. Comments, complements, and refinements
PublicationSwitched Capacitor Converters (SCC) form useful blocks in low/medium power applications as they are suitable for integration, both as off-chip and on-chip IC realizations. However, the problem with SCC is that their voltage conversion ratio is topology-dependent. By changing the SC circuit configuration, we can gain control over voltage conversion but the available ratio remains of a discrete nature, i.e. it maps into a countable...
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Bioelectronic nose: Current status and perspectives
PublicationA characteristic feature of human and animal organs of smell is the ability to identify hundreds of thousands of odours. It is accompanied by particular smell sensations, which are a basic source of information about odour mixture. The main structural elements of biological smell systems are the olfactory receptors. Small differences in a structure of odorous molecules (odorants) can lead to significant change of odour, which is...
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Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters
PublicationThe magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the...
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Guanosine Dianions Hydrated by One to Four Water Molecules
PublicationIntermolecular interactions such as those present in molecule···water complexes may profoundly influence the physicochemical properties of molecules. Here, we carried out an experimental–computational study on doubly deprotonated guanosine monophosphate···water clusters, [dGMP – 2H]2–·nH2O (n = 1–4), using a combination of negative anion photoelectron spectroscopy (NIPES) with molecular dynamics (MD) and quantum chemical (QM) calculations....
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Sensitivity of the Baltic Sea level prediction to spatial model resolution
Publicationhe three-dimensional hydrodynamic model of the Baltic Sea (M3D) and...
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Performance of the PEM fuel cell module. Part 2. Effect of excess ratio and stack temperature
PublicationThe paper describes a fuel cell based system performance under different thermal conditions. The system could be fed with bottled hydrogen or with very high purity hydrogen obtained from reforming of methanol. The system is based on two fuel cell units (1.2 kW each, produced by Ballard Power Systems Inc. and called Nexa), DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and...
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Low cost set-up for supercapacitors parameters evaluation
PublicationSupercapacitors are capable to store relatively high amount of energy comparing to its mass. Growing number of these devices applications requires development of new testing methods. Standard methods of evaluation of supercapacitor parameters, as cycling voltammetry, CV, galvanostatic cycling with potential limitation, GCPL, impedance measurements, require equipment of high cost...
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Four-Port Circulator Using Reduced Ground Plane Ferrite Coupled Line Junction
PublicationIn this paper the investigations of four-port circula-tor using longitudinally magnetized ferrite coupled line section are presented. The device is designed by cascading ferrite section with magic-T junction ensuring its even and odd mode excitation. The scattering parameters of ferrite coupled line junction are calculated using own software and verified with the use of commercial software. The even and odd excitation of ferrite...
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Spectroscopic wireless sensor of hematocrit level
PublicationAn optical method for hematocrit measurement is presented. The sensor, designed and developed by authors, consists of a spectroscopic set-up and a microcontroller. The work of the sensor is based on measurement of intensity of two selected spectral bands. Tests confirmed the ability of the sensor to determine the hematocrit level with appropriate measurement accuracy. Measurement results can be transmitted via wireless module to...
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Safety at railway level crossings and Vision Zero
PublicationIn this work, safety analysis at the railway level crossings is presented using advanced mathematical modelling. Resistivity of track subgrade panels is taken into account. The analysis does not refer to the assessment of the current regulations. Specific cases of generalized dynamic system are considered by introducing operations S=Δ, S=P defined in space C(N) of real sequences. In this model, generalized discrete exponential...
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MEASURE OF THE LEVEL OF SOCIO-ECONOMIC DEVELOPMENT IN PROVINCES
PublicationThe scope of Polish macro-economic data for assessing the level of socio-economic development of the country is largely limited because of the regional variation. Therefore there is a need for cyclic selection and the verification of criteria which allow identifying regions with a similar level of socio-economic development or those that clearly differ from the mean values. The aim of the study is to compare Poland’s provinces...
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Management of Textual Data at Conceptual Level
PublicationThe article presents the approach to the management of a large repository of documents at conceptual level. We describe our approach to representing Wikipedia articles using their categories. The representation has been used to construct groups of similar articles. Proposed approach has been implemented in prototype system that allows to organize articles that are search results for a given query. Constructed clusters allow to...
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Integrated Three-Level Dual-Phase Inverter
PublicationIn view of reducing the number of inverter legs that provide dual-phase, three-level output voltages (as may be needed in an uninterruptible power supply), and that also provide a wide range of output frequencies (as needed in an advanced motor drive system with wide speed ranges), a three-level, dual-phase inverter topology is presented in this paper. Its three-level attribute was based on the F-type inverter topological concept,...
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Four-state stochastic model of changes in the reliability states of a motor vehicle
PublicationThe properties of semi-Markov processes have been generally characterized and the applicability of the theory of such processes to the determining of the reliability of motor cars and other road vehicles has been explained. A formal description of the process of changes in the motor vehicle technical states considered as reliability states and a model of this process in the form of a one-dimensional stochastic process have been...
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High-Level Model for the Design of KPIs for Smart Cities Systems
PublicationThe main goal of the paper is to build a high-level model for the design of KPIs. Currently, the development and processes of cities have been checked by KPI indicators. The authors realized that there is a limited usability of KPIs for both the users and IT specialists who are preparing them. Another observation was that the process of the implementation of Smart Cities systems is very complicated. Due to this the concept of a...
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Four-body recombination in organic bulk heterojunction solar cells: an alternative interpretation
PublicationWe demonstrate a new interpretation of the previously reported quadrimolecular recombination in organic bulk heterojunction solar cells. It is suggested that the recently described (Szmytkowski 2012 Phys. Status Solidi RRL 6 300) interaction between exciton and electron–hole Langevin bound pair formed across the donor–acceptor interface is a four-particle process. This is in opposition to the treatment of this effect as a three-particle...
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Hybrid‐mode single‐slope ADC with improved linearity and reduced conversion time for CMOS image sensors
PublicationIn the paper, a single‐slope analog‐to‐digital converter (ADC) for integrated CMOS image sensor applications with an improved technique of conversion has been proposed. The proposed hybrid‐mode ADC automatically uses one of the following conversion techniques: time based (i.e. PWM) or voltage based (i.e. single‐slope). During the ADC operation, the clock frequency and reference voltage are modified in order to reduce the conversion...
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Counting Lattice Paths With Four Types of Steps
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Analysis of balancing of four stroke V6 engines
PublicationAnalysis of balance of V6 engines with a common-pin crankshaft depending on a cylinder bank angle and the crank radius to connecting rod length ratios , based on the relations derived, is presented in the paper. The bank angles providing the lowest moment of inertia forces in reciprocating motion, for selected values, were determined. The position of the plane of the main counterweights in order to maximum balance of the moment...
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Great Villas of Visegrad Four Countries and Slovenia
PublicationWystawa zorganizowana w Parlamencie Europejskim w Brukseli w dniach 27-30 maja 2013 przez Agencję Foibos Books Praha na której wystawiono plansze autorstwa Marii Jolanty Sołtysik opartej na książce Great Villas of Poland, oprac zb. pod red. R. Nakoniecznego, Praha : Foibos Books, 2013, ISBN 978-80-87073-58-2.
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The added value of using the HEPA PAT for physical activity policy monitoring: a four-country comparison
PublicationBackground Public policy is increasingly recognized as an important component of physical activity promotion. This paper reports on the current status of physical activity policy development and implementation in four European countries based on the Health-Enhancing Physical Activity Policy Audit Tool (HEPA PAT) developed by WHO. It compares the findings to previous studies and discusses the general utility of this tool and its...
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Automatic Analysis System of TV Commercial Emission Level
PublicationThe purpose of the study was to determine whether the commercial emission level is higher than the emission level of a regular program and to check if the commercials broadcasters follow the recommended levels of loudness. The paper shortly reviews some chosen methods of volume measurements specified in the ITU and EBU recommendations. Then, it describes a prototype of a system implemented in Embarcadero C++ Builder 2010 which...
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High-speed memoryless binary/residue converter
PublicationW pracy zaprezentowano nowy szybki konwerter z systemu binarnego do systemu resztowego dla liczb o zakresie do 60 bitów. W konwerterze stosowane są wyłącznie układy kombinacyjne. Algorytm konwertera oparty jest na dodawaniu niezerowych cyfr binarnych reprezentacji kolejnych potęg 2 modulo m. Dodawanie jest realizowane przy użyciu wielooperandowego sumatora CSA oraz sumatora CPA. Suma wyjściowa CPA jest redukowana do zakresu 2m-1...
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RSN reverse converter based on core function
Publicationzaprezentowano nową architekturę konwertera z systemu resztowego do systemu binarnego opartego na funkcji jądra dla modułów 5-bitowego. Zastosowano niekrytyczną funkcję jądra.Obliczanie funkcji jądra jest realizowane przy użyciu chińskiego twierdzenia dla funkcji jądra (CRTCF). Założono także, że jeden z modułów jest potegą 2. Architektura ta umożliwia zmniejszenie złożoności sprzętowej o ok. 12.5% w porównaniu z innymi architekturami...
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The Electrical Drive Systems with the Current Source Converter
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Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublicationExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
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Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
PublicationThe article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies...
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Real-time hybrid model of a wind turbine with doubly fed induction generator
PublicationIn recent years renewable sources have been dominating power system. The share of wind power in energy production increases year by year, which meets the need to protect the environment. Possibility of conducting, not only computer simulation, but also laboratory studies of wind turbine operation and impact on the power system and other power devices in laboratory conditions would be very useful. This article presents a method...
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Determining and verifying the safety integrity level with security aspects
PublicationSafety and security aspects consist of two different group of functional requirements for the control and protection systems. It is the reason why the analyses of safety and security shouldnt be integrated directly. The paper proposes extension of the currently used methods of functional safety analyses. It can be done with inclusion of the level of information security assigned to the technical system. The article addresses some...
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Multifaceted Analyses of Four Different Prototype Lightweight Photovoltaic Modules of Novel Structure
PublicationDynamic growth of photovoltaic capacity in Poland encourages many entities to invest in photovoltaic systems. However, in the case of buildings with low roof-bearing capacity it can be problematic or even impossible to mount conventional PV modules due to their relatively high weight. Hence, the use of lightweight PV modules is a potential solution. In this paper four different prototype silicon lightweight modules of novel structure...
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Reflections on the relationship-level between national- and voivodship-level planning In Poland
PublicationPrzedstawiono stan i ocenę procesu planowania, przesłanki i zamierzenia zmian oraz wybrane propozycje w zakresie relacji między planowaniem krajowym a planowaniem rozwoju i zagospodarowania przestrzennego na poziomie województwa.
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Determining and verifying the safety integrity level of the controland protection systems under uncertainty
PublicationThe probabilistic models of the electrical, electronic and programmable electronic (E/E/PE)systems, which are proposed in the IEC 61508 and IEC 61511 standards, do not cover the uncertainty aspectsof results obtained from these models. The proposed method takes into consideration the sensitivity analysisof probabilistic models of E/E/PE systems as well as the uncertainty of probabilistic results. It uses differentialfactors, which...
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Level of public finances decentralization in European Union countries
PublicationResearch background: Despite of the universality of the implementation in democratic countries the principle of decentralization resulting from the belief that it is an instrument to improve the efficiency of public funds management, both the scope of public services and the level of decentralization in individual countries are not identical. Purpose of the article: Comparison the scope of fiscal decentralization...
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Integrity level verification for safety-related functions
PublicationThis article describes methods for safety integrity level (SIL) verification of safety-related functions with regard to probabilistic criteria given international standards IEC 61508 and IEC 61511. These functions are to be realized using the electrical, electronic and programmable electronic (E/E/PE) systems or safety instrumented systems (SIS). Some methods are proposed for quantitative probabilistic modelling taking into account...
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Modelling selected road safety measures at the regional level in Europe
PublicationRegions are Europe’s basic levels of management. The literature was reviewed to identify regional safety analyses and some of the factors that are important for road safety in the regions. Next, data were collected atthe regional NUTS 2 level in Europe for the years 1999-2008. An analysis of the data helped identify f actors which have the strongest bearing on fatalities and other safety measures. This paper presents the initial...
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Commissioning of the CMS experiment and the cosmic run at four tesla
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