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Search results for: POWER QUALITY
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Communication Platform for Evaluation of Transmitted Speech Quality
PublicationA voice communication system designed and implemented is described. The purpose of the presented platform was to enable a series of experiments related to the quality assessment of algorithms used in the coding and transmitting of speech. The system is equipped with tools for recording signals at each stage of processing, making it possible to subject them to subjective assessments by listening tests or, objective evaluation employing...
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Quality testing methods of foil-based capacitors
PublicationKondensatory foliowe są powszechnie stosowanymi elementami pasywnymi w ukłądach zasilania. Dotychczasowe metody oceny ich jakości są długotrwałe oraz zużywają energię. W pracy przedstawiono propozycje szeregu nowych, bardziej efektywnych metod, które mogą być z sukcesem stosowane podczas ich produkcji.
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Nonquadratic quality indices in estimation, approximation and control
PublicationZaproponowano wykorzystanie niekwadratowych miar jakości w zagadnieniach estymacji parametrów modeli, aproksymacji funkcji okresowych oraz syntezy układów sterowania. Rozważono funkcje celu w postaci ważonych sum lub całek wartości bezwzględnej błędu predykcji. Ponieważ tego typu wskaźniki jakości są w swoich ekstremach nieróżniczkowalne, zadanie minimalizacji funkcji celu rozwiązano stosując iteracyjny algorytm kolejnych przybliżeń....
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Evaluation of IEEE 802.11E extensions for quality of service
PublicationZaprezentowano założenia wersji "e" standardu 802.11, wspierającej obsługę zróżnicowanych, pod względem potrzeb QoS, strumień ruchu. Przeprowadzono różnorodne badania symulacyjne dla opcji EDCF oraz HCF tego standardu. Wskazano na mankamenty oraz zalety nowych rozwiązań.
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Quality inspection system in flexible manufacturing cell.
PublicationPublikacja dotyczy struktury procesu produkcyjnego w środowisku komputerowo zintegrowanego wytwarzania (computer integrated manufacturing - CIM). Ukazuje ona aspekty kontroli jakości wykonania części na różnych etapach procesu wytwórczego, podkreślając jego istotność. W celu dokonania szczegółowej analizy problemu zebrano dane o jakości wykonania części na poszczególnych poziomach wytwarzania. Analizy dowiodły, że jakość wykonania...
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Passive samplers in indoor air quality control
PublicationPrzedstawiono wyniki badań jakości powietrza wewnętrznego w 12 wybranych mieszkaniach usytuowanych na terenie aglomeracji Trójmiejskiej z wykorzystaniem techniki pasywnej (dozymetria pasywna typu permeacyjnego) oraz techniki dynamicznej (rurki sorpcyjne wypełnione sorbentem Tenax TA). Wykorzystując nowe podejście do sposobu kalibracji dokonano monitoringu zarówno poszczególnych lotnych związków organicznych jak i sumarycznej zawartości...
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Expert systems in quality control of manufacturing processes
PublicationThe paper deals with quality control in conditions of computer integrated manufacturing (CIM). It shows that quality of material stream items have to be analyzed on every stage of manufacturing process. Collecting and analyzing quantity of data with usage of expert systems make it possible to create a system for coordination of cell's work. The system contains error recovery algorithm and adaptive control subsystem based on fuzzy...
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Low-Voltage Low-Power Filters with Independent ω0 and Q Tuning for Electronic Cochlea Applications
PublicationAn acoustic second-order low-pass filter is proposed for filter banks emulating the operation of a human cochlea. By using a special filter structure and an innovative quality (Q)-factor tuning technique, an independent change of the cutoff frequency (ω0) and the Q-factor with unchanged gain at low frequencies is achieved in this filter. The techniques applied result in a simple filter design with low Q-factor sensitivity to component...
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Stability Analysis of Shunt Active Power Filter with Predictive Closed-Loop Control of Supply Current
PublicationThis paper presents a shunt active power filter connected to the grid via an LCL coupling circuit with implemented closed‐loop control. The proposed control system allows selective harmonic currents compensation up to the 50th harmonic with the utilization of a model‐based predictive current controller. As the system is fully predictive, it provides high effectiveness of the harmonic reduction, which is proved by waveforms achieved...
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Concept of Compatibility Region for the Evaluation of IR UWB Electromagnetic Compatibility
PublicationThis paper presents a new proposal for the unified evaluation of ultra wideband and narrowband radio communication systems electromagnetic compatibility, called “compatibility region”. The idea of compatibility region is based on the relation between the ratio of narrowband to ultra wideband signal power in a receiver and some transmission quality indicators (bit error rate, effective data rate).
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Coupled inductors based filter for matrix converters
PublicationThe use of the coupled inductors in the multipulse matrix converter (MC) systems is described in the paper. The possible arrangements of the system are given together with the description of their operation parameters. Moreover, the influence of the system’s topology on the output power quality is also presented. The invented converter structures evaluation results are given in the form of simulation tests acquired output waveforms...
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Unidirectional DC/DC Converter with Voltage Inverter for Fast Charging of Electric Vehicle Batteries
PublicationThe paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable speed motor drives and charging of EV batteries. It has been shown that it is possible to support the supply of drive voltage frequency converters (VFCs) and charging...
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Quality of Satellite Communication in Selected Mobile Android Smartphones
PublicationToday, thanks to mobile devices, satellite communication is available to anyone and everywhere. Gaining information on one’s position using GNSS (Global Navigation Satellite Systems), particularly in unknown urban environments, had become an everyday activity. With the widespread of mobile devices, particularly smartphones, each person can obtain information considering his or her location anytime and everywhere. This paper is...
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TEMPERATURE INFLUENCE ON TIRE ROLLING RESISTANCE MEASUREMENTS QUALITY
PublicationGlobal warming makes it necessary to reduce energy consumption, which in the case of motor vehicles, is connected, among other things, with reduction of resistive forces acting on a vehicle during its motion. One of the most important components of those forces is rolling resistance, which is very difficult to measure, especially in road conditions. The article deals with issues related to the influence of the thermal state of...
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Concept of managing quality in baking industry, in vector representation
PublicationThe author introduced an innovative metrisable method of describing a manufacturing process. The idea of vector structure of a manufacturing process allows to formulate quantitative relations between the activity of input streams, elements of product quality, and measurable effects of losses. The structure was basis for the formulation of the concept of the process of managing product quality in the baking industry in a vector...
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QUALITY GAPS IN HIGHER EDUCATION FROM THE PERSPECTIVE OF STUDENTS
PublicationThe presented research work relates to the category of quality in higher education. This article aims to present the determinants of the quality of education in the context of international standards. The background of the considerations is the Bologna Declaration and the European Higher Education Area. The results of the research carried out with the use of the nominal group method and the data analysis carried out based on the...
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Polymodal Method of Improving the Quality of Photogrammetric Images and Models
PublicationPhotogrammetry using unmanned aerial vehicles has become very popular and is already commonly used. The most frequent photogrammetry products are an orthoimage, digital terrain model and a 3D object model. When executing measurement flights, it may happen that there are unsuitable lighting conditions, and the flight itself is fast and not very stable. As a result, noise and blur appear on the images, and the images themselves can...
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Quality of limes juices based on the aroma and antioxidant properties
PublicationKaffir (Citrus hystrix) and Key (Citrus aurantifolia) limes juices were investigated and compared. Two dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF-MS) was applied to assess the botanical origin of Kaffir and Key limes juices, based on volatile substances. The biggest differences in the contents of selected terpenes in Kaffir and Key limes occur in chemical compounds such as Limonene,...
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Electronic noses: Powerful tools in meat quality assessment
PublicationMain factors that are considered by consumers when choosing meat products are colour and aroma, of which the latter is a more reliable indicator of quality. However, a simple sensory evaluation of hedonistic qualities is often not sufficient to determine whether protein is past its shelf life, and consumption of spoiled meat can lead to serious health hazards. Some volatile compounds can be used as spoilage indicators, and so a...
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Application of gas chromatography to evaluate the quality of rapeseed oil
PublicationTwo-dimensional gas chromatography is an analytical technique, which is increasingly being used in food research. Through the analysis of volatile fraction, it is possible to determine the quality of food products. One of the reasons for the deterioration of food is thermal degradation. Products that are often subject to degradation reactions due to temperatures are edible oils. In the thesis, the results of edible oils with different...
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Reliability of quality forecast for hybrid metal-working machinery
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Improving Objective Speech Quality Indicators in Noise Conditions
PublicationThis work aims at modifying speech signal samples and test them with objective speech quality indicators after mixing the original signals with noise or with an interfering signal. Modifications that are applied to the signal are related to the Lombard speech characteristics, i.e., pitch shifting, utterance duration changes, vocal tract scaling, manipulation of formants. A set of words and sentences in Polish, recorded in silence,...
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Mathematical models of process quality on the example of the bakery industry
PublicationThis article presents a new approach to quantitative dimensionless assessment of the efficiency and competitiveness of production processes. New concepts of process quality and relative product quality have been introduced. Process quality was expressed in vector and scalar. The process quality vector ono was expressed by the product of reliability by the vector from the sum of three components taking into account the composition...
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The critical factors of landfill fire impact on air quality
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Quality system documentation of smes in process management framework
PublicationThe article presents elements of original methodology of process-oriented quality management system implementation to be applied in small organizations. The primary objective of the paper is to show process based documentation structure of a quality system and simple method of processes control description. Thus, guidelines for preparation of quality system documentation in process management framework, related research results...
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Multidimensional Approach to Quality Analysis of IPSec and HTTPS Applications
PublicationNiniejsza praca omawia aspekty bezpieczeństwa i wydajności aplikacji rozproszonych działających w środowisku sieci publiczno-prywatnych, stworzonych za pośrednictwem technologii IPSec i HTTPS. Jako przykłady implementacji pokazane są: jeden z największych polskojęzycznych portali motoryzacyjnych: www.auto.gda.pl oraz brama IPSec działająca w środowisku ATCA. Przedstawiona w referacie analiza pod kątem wydajności i bezpieczeństwa...
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Classification of high-voltage varistors into groups of differentiated quality
PublicationThe research was aimed on defining a factor of quality for high-voltage varistors using Non-Destructive Testing (NDT) techniques, which could be applied during the production testing. The newly proposed parameter Q determined on the basis of the lowest resonant frequency fr measured within the preselected frequency range was taken into account. The parameter Q was defined for ZnO structures after firing, without metallized contacts....
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Application of gaze tracking technology to quality of experience domain
PublicationA new methodological approach to study subjective assessment results employing gaze tracking technology is shown. Notions of Human-Computer Interaction (HCI) and Quality of Experience (QoE) are shortly introduced in the context of their common application. Then, the gaze tracking system developed at the Multimedia Systems Department (MSD) of Gdansk University of Technology (GUT) is presented. A series of audio-visual subjective...
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Quality measure of VoIP services in carrier grade systems
PublicationThis paper describes passive measurement method of VoIP services quality in carrier grade systems, engaging slight system resources. Measurement is based on analyzing quality information in sender and receiver reports in RTCP packets sent by the end points of RTP session. Data is analyzed and stored by Session Boarder Controllers SBC. Objective evaluation of VoIP calls is based on quality information of IP connection and voice...
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Quality prediction of foil capacitors by acoustic emission signals
PublicationJakość i trwałość kondensatorów foliowych jest zależna od ich warunków pracy (np. nadmiarowego napięcia pracy, temperatury, wilgotności) oraz od potencjalnych defektów wprowadzonych na różnych etapach wytwarzania kondensatorów. Nieustanny nacisk na wzrost jakości wytwarzanych elementów przy jednoczesnej redukcji kosztów wytwarzania oznacza, że nowe, tanie i szybkie metody predykcji jakości tych elementów są mocno poszukiwane. W...
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Determination of some off-flavors for vodka quality assessment
PublicationW pracy zostały przedstawione wyniki analizy wybranych związków karbonylowych w wódkach czystych z wykorzystaniem procedury HS-SPME/GC-ECD poprzedzonej derywatyzacją aldehydów za pomocą odczynnika PFBHA. Przeprowadzone badania wykazały, że obecność 2,3-pentanodionu i 2-butenalu skutkuje pogorszeniem jakości analizowanych wódek.
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Mobile monitoring system for control of atmospheric air quality
PublicationW pracy przedstawiono ruchomy system monitoringu powietrza, który zapewnia możliwość ciągłego pomiaru stężenia takich zanieczyszczeń powietrza jak benzen, tlenek i ditlenek azotu oraz tlenek i ditlenek węgla. Opracowany zestaw pomiarowy może być zainstalowany na rożnych pojazdach (samochód, autobus, ciężarówka).System zbudowany jest z zestawu małych przenośnych jednostek pomiarowych (elektroniczne urządzenia pomiarowe, rejestrator...
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Quality of Resilience in IP-based Future Internet Communications
PublicationInternet Przyszłości (zwany również Internetem 3.0 czy też NGN) jest następnym krokiem ewolucji Internetu. Prace badawcze związane z nową architekturą obejmują szerokie spektrum zagadnień, a zwłaszcza: architekturę sieci (protokoły), technologie sieciowe, aplikacje, itd. W tym artykule zakładamy wykorzystanie koncepcji Differentiated Services (DiffServ). W szczególności, proponujemy podejście ochrony zróżnicowanej ruchu. Jest ono...
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Process management methodology for quality systems of small organizations
PublicationW artykule przedstawiono najważniejsze elementy metodyki wdrażania zorientowanych procesowo systemów zarządzania jakością wg normy ISO 9001. Zaprezentowano przykład struktury procesów systemu jakości oraz prosta metodę opisu procesów (przewodnik procesu). Omówiono założenia metodyki oraz wybrane sposoby nadzorowania procesów. W podsumowaniu wskazano korzyści płynące ze stosowania metody w małych organizacjach.
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The role of process approach in quality systems of small firms
PublicationW opracowaniu przedstawiono znaczenie orientacji procesowej w systemach zarządzania jakością ze szcególnym uwzględnieniem mniejszych organizacji. Zaprezentowano wyniki badań potwierdzających znaczący wpływ podejścia procesowego na skuteczność sytemów jakości. Przedstawiono też kluczowe problemy i oczekiwania sektora MŚP odnośnie do wdrażania zorientowanych procesowo systemów zarzadzania jakością.
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Lubricity-based estimation of the changes in the brake fluid quality
PublicationW artykule przedstawiono, na podstawie wyników badań laboratoryjnych, możliwość określenia wartości smarności łączącej własności fizykochemiczne i reologiczne płynów. Smarność, która została określona dla trzech płynów hamulcowych (oznaczenia zastrzeżone przez firmę zlecającą porównanie ich własności), umożliwiła wybór najlepszego, który pewnie zostanie zastosowany w instalacjach hamulcowych samochodów.
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Methodology of semiconductor devices classification into groups of differentiated quality
PublicationZaproponowano klasyfikację przyrządów półprzewodnikowych do grup o zróżnicowanej jakości na podstawie ich szumów własnych z zakresu małych częstotliwości. Przedstawiono metodologię umożliwiającą stwierdzenie, czy zaproponowany parametr szumowy X dla danego typu przyrządu półprzewodnikowego może być stosowany do określenia jakości. Sprecyzowano przebieg badań wstępnych bazujących na ocenie wyników pomiarów szumów własnych z zakresu...
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Integrating quality criteria and methods of evaluation for software models
PublicationRozdział podejmuje zagadnienia jakości modeli w inżynierii oprogramowania. Zawiera on przegląd i systematyzację kryteriów jakości modeli oraz metod oceny jakości modeli. Podaje metodologię tworzenia metod oceny jakości modeli w zależności od kryteriów jakości oraz innych parametrów oceny. Zawiera również studia przypadków zastosowania tej metodologii.
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Human Development and Quality of Institutions in Highly Developed Countries
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A proposal for a knowledge market based on quantity and quality of knowledge
PublicationThe paper proposes an autonomous market environment in which it is possible to trade knowledge based on its quantity and quality.
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QUALITY OF SWEET POTATO AS A RAW MATERIAL FOR FOOD PROCESSING
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Membrane processes used for potable water quality improvement
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Helicopter Intelligence in Hover Quality Improvement of the Fuzzy Regulator
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Digital Audio Broadcasting or Webcasting: A Network Quality Perspective
PublicationIn recent years, many alternative technologies of delivering audio content have emerged, with different advantages and disadvantages. In this paper pros and cons of digital audio broadcasting and webcasting transmission techniques in a network quality perspective are described. A case study of user expectations with respect to currently available services is analyzed, and the perceived quality of real digital broadcasted and webcasted...
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Assessment of Supercapacitor’s Quality by Means of Low Frequency Noise
PublicationLow frequency noise is a well-known tool for quality and reliability assessment of electronic devices. This phenomenon is observed in different electrochemical devices as well (e.g., smart windows, electrochemical corrosion processes). Thus, we can assume that the same tool can be used to asses quality of supercapacitors. Their quality is usually determined only by capacitance and/or equivalent series resistance (ESR), or impedance....
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Distinctive facades of commercial buildings and the quality of public space,
PublicationMutual relations between the retail center and public spaces of the city are varied. They depend on the type and size of the commercial structure. Other ones are for multifunctional shopping centers and other for high streets. In megastores and shopping malls the essential for their functioning is their interior and entrance, which is sometimes the only place of interpenetration of the commercial structure with the surrounding...
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An assessment of teeth quality of the mini gang saw blade
PublicationIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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The Quality of the Outflow from Conventional WWTPs and Treatment Wetlands
PublicationUntil recently the humic substances were considered to have no negative impact on human health. Therefore elimination of these substances from potable water was only performed due to aesthetic reasons. In the recent years, however, it was found out that humic substances may cause unacceptable smell of water or cumulate toxic substances by complexing metal ions and adsorption of persistent organic pollutants such as pesticides,...
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Indoor air quality in public utility environments-a review
PublicationIndoor air quality has been the object of interest for scientists and specialists from the fields of science such as chemistry, medicine and ventilation system design. This results from a considerable number of potential factors, which may influence the quality of the broadly understood indoor air in a negative way. Poor quality of indoor air in various types of public utility buildings may significantly affect an increase in the...
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Sound quality metrics applied to road noise evaluation
PublicationRoad noise monitoring systems typically measure sound levels in specific time periods. The more insightful approach suggests to measure also the nature of noise. Sound quality of sounds such as car noise can be objectively evaluated by several parameters. One of them is psychoacoustic annoyance, described by loudness, tone color, and the temporal structure of sound. In this paper the assessment of several sound quality parameters, such...