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Search results for: GOS, QOS
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Occurrence and Determination of Volatile Fatty Acids in Landfill Leachate and Gas
PublicationIn landfills containing biological matter volatile fatty acids (VFAs) are generated at high rate at the early stage of waste disposal and their content in leachate is high as compared to the leachate from old parts of landfill since they are converted to methane gas. Monitoring of the leachate for the content of VFAs can help determine the processes occurring in waste and possible effect of the leachate on the environment in the...
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Efektywność filtracji przestrzennej sygnałów w przeciwdziałaniu spoofingowi GPS
PublicationPrzedstawiono metodę przeciwdziałania spoofingowi GPS poprzez formowanie minimum charakterystyki kierunkowej układu antenowego. Opisano metodykę i wyniki badań tłumienia sygnałów niepożądanych w obecności szumu. Zaprezentowano rezultaty statystycznej analizy wpływu filtracji przestrzennej na tłumienie prawdziwych sygnałów GPS. W podsumowaniu wykazano korzyści wynikające z użycia przyjętej metody, w...
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Toward Safe and Efficient Recovery of Gas Munitions Dumped at Sea
PublicationThe proposal of a system for the safe recovery of unexploded ordnance (UXO), chemical weapons (CW) and chemicalwarfare agents (CWA) dumped at sea mainly after WWI and WWII is described in this work. The proposed solutionaddresses the tasks required to neutralise thousands of tons of dumped material and the currently available solutionsand proposed ideas. Requirements concerning the features of a recovery system are defined and...
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A calibration model for gas sensor array in varying environmental conditions
PublicationAbstract: Gas-analyzing systems based on gas sensors, commonly referred to as electronic noses, are the systems which enable the recognition of volatile compounds in their working environment and provide the on-line results of analysis. The most commonly used type of sensors in such systems is semiconductor gas sensors. They are considered to be the most reliable in the long-term applications (more than 1 year), however,...
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Detection and Mitigation of GPS Spoofing Based on Antenna Array Processing
PublicationIn this article authors present an application of spatial processing methods for GPS spoofing detection and mitigation. In the first part of this article, a spoofing detection method, based on phase delay measurements, is proposed. Accuracy and precision of phase delay estimation is assessed for various qualities of received signal. Spoofing detection thresholds are determined. Efficiency of this method is evaluated in terms of...
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IMPEDANCE MEASUREMENT MODULE FOR GAS SENSORS WITH TEMPERATURE CONDITIONING FEATURE
PublicationThe paper presents an impedance measurement module which is aimed for gas sensor. Sensor’s heater temperature conditioning and modulation feature is available in order to allow implementation of different techniques improving selectivity and sensitivity of gas sensors. The measurement module uses three-parameter sine-fitting technique for impedance measurement. To monitor sensor temperature, the resistance of the sensor’s heater...
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LOW COST MEASUREMENT MODULE FOR MATRIX OF AMPEROMETRIC GAS SENSOR
PublicationThis paper describes an amperometric sensor module for gas concentration measurement. A module can be used for many types of electrochemical gas sensors without major hardware changes. Device is based on AVR ATmega8 microcontroller. As signal processing circuit a specialized integrated circuit LMP9l000 configurable via I2C interface is used. The concept of a measuring system composed of several modules dedicated for a gas sensors...
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Efficiency of gas detection algorithms using fluctuation enhanced sensing
PublicationEfficiency of various gas detection algorithms by applying fluctuation enhanced sensing method was discussed. We have analyzed resistance noise observed in resistive WO3- nanowires gas sensing layers. Power spectral densities of the recorded noise were used as the input data vectors for two algorithms: the principal component analysis (PCA) and the support vector machine (SVM). The data were used to determine gas concentration...
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Meat freshness classification using ultra-fast gas chromatography
PublicationMeat constitutes an important component of human diet. In order to ensure that it is safe to consume, it is important to be able to determine whether a particular sample is fresh. To this end, an analysis of the headspace of pork, beef, and poultrywas performed over a period of seven days using ultra-fast gas chromatography. Compounds that may possibly be used as indicators of spoilage were identified. Based on the obtained results...
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Experimental investigation of domestic gas boiler fitted with ORC module
PublicationIn the paper the prototype of innovative domestic cogenerative ORC system, consisting of a conventional gas boiler and a small size axial vapour microturbines (in-house designed for ORC and the commercially available for Rankine cycle (RC)), evaporator and condenser were scrutinised. In the course of study the fluid working temperatures, rates of heat, electricity generation and efficiency of the whole system were obtained. The...
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Techniques of acquiring additional features of the responses of individual gas sensors
PublicationGas sensors usually exhibit lack of selectivity, require fre quent calibration, exhibit drift of the response and a lot of factors, such as humidity or ambient temperature, influen ce their performance. Different approaches can be used to overcome this shortcomings. Building arrays of different sensors and usage of pattern recognition methods to analyze responses of elements...
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Gas turbines – technological development and potential use in CAES systems
PublicationThis article briefly describes Compressed Air Energy Storage (CAES), focusing on the technological development of one of the key elements of such systems – the gas turbines. It presents the basic parameters and features of gas turbines, as well as turbine classes with example models. Main tendencies in the structural and technological development are discussed. Changes and trends on electric energy markets are becoming more and...
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Compressible gas density measurement by means of Fourier analysis of interferograms
PublicationThis paper describes a method for nonintrusive compressible gas density measurement by means of automated analysis of interferograms using FFT (Fast Fourier Transform), and its implementation using DFT (Discrete Fourier Transform), that does make this measurement technique a fairly valuable and accessible experimental method. The presented approach makes it possible to use the finite fringe setting of the interferometer, thus reducing...
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A novel architecture of Web-GIS for mapping and analysis of echinococcosis in Poland
PublicationEchinococcosis is an infectious disease transferred through ingestion of food or water which have been contaminated with eggs of the Echinococcus tapeworm, which are spread by intermediate parasite hosts. Because the latter are primarily territorial, research related to diagnosis and prevention of echinococcosis requires investigation of environmental factors, which can be supported with the use of a Geographical Information System...
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Technical and Economic Analysis of the Supercritical Combined Gas-Steam Cycle
PublicationCombined cycle power plants are characterized by high efficiency, now exceeding 60%. The record-breaking power plant listed in the Guinness Book of World Records is the Nishi-Nagoya power plant commissioned in March 2018, located in Japan, and reaching the gross efficiency of 63.08%. Research and development centers, energy companies, and scientific institutions are taking various actions to increase this efficiency. Both the gas...
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Development of Gas Sensor Array for Methane Reforming Process Monitoring
PublicationThe article presents a new method of monitoring and assessing the course of the dry methane reforming process with the use of a gas sensor array. Nine commercially available TGS chemical gas sensors were used to construct the array (seven metal oxide sensors and two electrochemical ones). Principal Component Regression (PCR) was used as a calibration method. The developed PCR models were used to determine the quantitative parameters...
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Hold-Up Problems in International Gas Trade: A Case Study
PublicationThe infrastructure required for international natural gas trade is considerable, which often leads to hold-up problems and supply disruptions. This study discusses disruptions of gas supply from Algeria, Indonesia, Russia, and Turkmenistan since the early 1980s. The novelty of this study is its focus on the issues related to transit countries, which are rarely considered in the literature. The results of the study classify supply...
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Low-energy positron scattering from gas-phase benzene
PublicationIn this paper we are presenting calculations of the elastic cross section of positrons with gas-phase benzene for the energy range from 0.25 eV to 9.0 eV. The calculations are done with the molecular R-matrix method for positron-scattering from poly-atomic molecules using a scaling factor to scale the electron-positron interaction. The scaling factor influences the position of the poles of the R-matrix. We adjust the scaling factor...
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Ammonia Gas Sensors: Comparison of Solid-State and Optical Methods
PublicationHigh precision and fast measurement of gas concentrations is important for both understanding and monitoring various phenomena, from industrial and environmental to medical and scientific applications. This article deals with the recent progress in ammonia detection using in-situ solid-state and optical methods. Due to the continuous progress in material engineering and optoelectronic technologies, these methods are among the most...
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Selected concentration techniques for gas chromatographic analysis of environmental samples
PublicationThe paper describes the role and tasks of environmental analysis and monitoring. It emphasises the leading role played by gas chromatography, especially when coupled with suitable sample preparation. This is demonstrated by some literature evidence and mainly by the author's original work on the design of sample preparation apparatus and development of GC-based methods of determination of a wide variety of organic pollutants in...
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Posłannictwo a satysfakcja. Kilka słów o satysfakcji - głos młodych
PublicationPrzedstawienie problematyki uzasadnionego dążenia do uzyskania satysfakcji z wykonywanej pracy zawodowej w tym przypadku zawodu architekta. Wiadomo, że zawód to trudny: obok siły przebicia, umiejętności twórczych, potrzeby stałego dokształcania się musi nieść z sobą świadomość postawy empatii wobec adresata swych poczynań podmiotu czyli konkretnego człowieka. Zawarto wypowiedzi absolwentów Wydziału Architektury Politechniki...
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Resistance Noise Higher-Order Spectrums in Nanoparticle Gas Sensors.
PublicationPrzedstawiono badania fluktuacji rezystancji sensora gazu wykonanego z nanocząstek WO3. Stwierdzono występowanie składowych o rozkładzie prawdopodobieństwa różnym od rozkładu Gaussa. W celu zwiększenia czułości i selektywności wykrywanych gazów zastosowan do analizy obserwowanych fluktuacji spektra wyższych rzędów.
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Gas turbine as ship prime mover - specific problems and prospects.
PublicationPrzedstawiono ewentualne możliwości zastosowania turbin gazowych w okrętownictwie. Analizowano aspekty ekologiczne, ekonomiczne i techniczne.
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Gas sensing by thermoelectric voltage fluctuations in SnO2 nanoparticle films
PublicationPrzedstawiono eksperymentalne wyniki wykrywania gazów za pomocą badania fluktuacji napięcia termoelektrycznego w warstwie SnO2 przygotowanej z jednorodnych ziaren o średnicy 20 nm. Obserwowano fluktuacje napięcia bez zewnętrznej polaryzacji warstwy SnO2. Intensywność obserwowanych fluktuacji przekraczała 1000-krotnie intensywność szumów termicznych. Obserwowane zjawisko może byc wykorzystane do zwiększenia czułości wykrywania...
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Simulations of behaviour of granular bodies using a lattice-gas automaton.
PublicationW artykule przedstawiono wyniki numerycznej analizy przepływu materiałów granulowanych podczas 3 różnych problemów: przepływu silosowego, przepływu kanałowego i tworzenia się nasypu. W modelu zaczerpniętym z teorii gazów przyjęto kolizje cząsteczek i dysypację energii. Wyniki porównano z doświadczeniami.
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Relationships Between Geographical and Virtual Proximity in Cluster Organisations
PublicationThe purpose of the paper is to explore the relationships between geographical and virtual proximity in cluster organizations (COs). The authors report the findings of a qualitative study conducted in four COs in Poland. The basic technique for collecting and analyzing data was an in-depth individual interview and qualitative content analysis. The research has shown that the relationships between geographical and virtual proximity...
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Nowe trasy drogowe a krajobraz warowny Gdańska.
PublicationArtykuł przedstawia zagrożenia krajobrazu historycznego Gdańska przy budowie nowych przedsięwzięć drogowych oraz skuteczne narządzie do jego ochrony i kształtowania, jakim jest procedura oceny oddziaływania na środowisko (OOS). Krajobraz zachowanych fortyfikacji nowożytnych Gdańska, zagrożonych planowanymi inwestycjami komunikacyjnymi - drogami i węzłami, służy jako tło do rozważań na temat możliwości wykorzystania procedury...
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Ocena wspierania przez protokół IPv6 transmisji multimedialnych
PublicationW pracy pokazano, że protokół IPv6 będący następcą IPv4 zapewnia nieznacznie większe możliwości realizacji usług QoS. Dzięki polom nagłówka datagramu IPV6 definiuje zarówno klasę usług, do jakiej należy dany datagram, jak też priorytety przesyłania danego datagramu. Dodatkowo routery są zobowiązane do przetwarzania datagramów z określonymi klasami usług jak i priorytetami. Łącząc IPv6 z protokołem RSVP można uzyskać minimalne...
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Testbed analysis of video and VoIP transsmission performance in IEEE 802.11 b/g/n networks
PublicationThe aim of the work is to analyze capabilities and limitations of different implementations of IEEE 802.11 technologies (IEEE 802.11 b/g/n), utilized for both video streaming and VoIP calls directed to mobile devices. Our preliminary research showed that results obtained with currently popular simulation tools can be drastically different than these possible in real-world environment, so, in order to correctly evaluate performance...
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Potent antitumor 4-methyl-1-nitroacridine C-1748 induces apoptosis only in part of colon cells
PublicationZbadaliśmy zdolność pochodnej 4-metylo-1-nitroakrydyny C-1748 do indukcji apoptozy w ludzkich komórkach nowotworów jelita grubego HCT-8 i HT29 w stężeniach biologicznie istotnych. Zjawisko apoptozy określiliśmy na podstawie zmian morfologicznych jak i biochemicznych tj. fragmentacji DNA, aktywacji kaspazy-3, spadku potencjału mitochondrialnego, eksternalizacji fosfatydyloseryny i pojawiania się frakcji sub-G1. Wykazaliśmy, że pochodna...
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Potent antitumor 4-methyl-1-nitroacridine C-1748 induces apoptosis only in part of colon cells
PublicationCelem przedstawionej pracy było zbadanie zdolności pochodnej 1-nitroakrydyny C-1748 do indukcji apoptozy komórek raka jelita grubego HCT8 i HT29 pochodzenia ludzkiego. Śmierć komórek była badana przez określony czas inkubacji komórek ze związkiem w stężeniach odpowiadających wartościom EC90 lub ich wielokrotnościom przez czas od 3 do 72 godzin. Uzyskane wyniki wskazują, że C-1748 indukuje apoptozę zależną od czasu tylko w części...
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Antecedents and Consequences of Brand Loyalty
PublicationThe objective of this paper is to review, systematize, and summarize empirical research on the antecedents and consequences of brand loyalty. The literature review has identified five categories of antecedents to brand loyalty associated with consumer, brand, social, corporate and relational factors. The type of loyalty formed varies according to the combination of various antecedents, with premium loyalty being considered the...
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Literature Review on Conceptualisation of Online Consumer Engagement
PublicationThe purpose of the current study is to develop a literature review on “online consumer engagement” (OCE). Articles from 2006 to 2016 published in the marketing journals and other related journals have been reviewed to summarise the OCE concept. Although there is not an agreed definition and conceptualisation of OCE, this study classified the concept as either behavioural or psychological within the dimensions of cognitive, emotional,...
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The influence of 4-substituted and unsubstituted derivatives of 1-nitroacridine on the cell cycle and induction of apoptosis in human cancer HT29 and HeLa S3.
PublicationZbadano wpływ pochodnych 1-nitroakrydyny C-1748 i C-857, w stężeniach biologicznie istotnych, na cykl życiowy oraz indukcję apoptozy komórek raka jelita grubego HT29 oraz raka szyjki macicy HeLa S3. Metodą cytometrii przepływowej wykazano, że 4-metylo-1-nitroakrydyna C-1748 powoduje akumulację komórek HT29 w fazie S i komórek HeLa S3 w fazie G2 cyklu komórkowego zaś związek C-857 indukuje akumulację komórek HT29 i HeLa S3 w fazie...
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Derivatives of 1-nitroacridine induce apoptosis only in a limited number of human colon adenocarcinoma cells
PublicationPraca dotyczy indukcji apoptozy w komórkach ludzkich raków okrężnicy HT29 i HCT8 pod wpływem pochodnych 1-nitroakrydyny: C-857 i C-1748. Wykazano, że związki te w stężeniach biologicznie istotnych (EC90) indukują apoptozę tylko w części populacji komórek. Efekt ten uzależniony był od czasu inkubacji komórek ze związkiem, a nie zależał od stężenia związku.
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Temperate Phages, Prophages, and Lysogeny
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Janusz Górski prof. dr hab. inż.
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Relay-aided Wireless Sensor Network Discovery Algorithm for Dense Industrial IoT utilizing ESPAR Antennas
PublicationIndustrial Internet of Things (IIoT) applicationsrequire reliable and efficient wireless communication. Assumingdense Wireless Sensor Networks (WSNs) operating in a harshenvironment, a concept of a Time Division Multiple Access(TDMA) based WSN enriched with Electronically SteerableParasitic Array Radiator (ESPAR) antennas is proposed andexamined in this work. The utilized...
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A non-uniform real-time speech time-scale stretching method
PublicationAn algorithm for non-uniform real-time speech stretching is presented. It provides a combination of typical SOLA algorithm (Synchronous Overlap and Add ) with the vowels, consonants and silence detectors. Based on the information about the content and the estimated value of the rate of speech (ROS), the algorithm adapts the scaling factor value. The ability of real-time speech stretching and the resultant quality of voice were...
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Superconductivity in the Endohedral Ga Cluster Compound PdGa5
PublicationSuperconductivity is observed below Tc = 1.6 K in an endohedral Ga cluster compound PdGa5 using magnetization and heat capacity measurements. Electronic structure calculations show that the density of states (DOS) at the Fermi level is dominated by Ga s and p states and that the overall shape of DOS is similar to what was found in other endohedral Ga cluster superconductors, such as MoxGa5x+1, ReGa5, and T2Ga9 (T = Rh and Ir)....
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Łagodzenie skutków - system czy prowizorka?
PublicationArtykuł omawia problematykę związaną z unikaniem, ograniczaniem i kompensowaniem skutków krajobrazowych i wizualnych, jakie mogą występować w związku z realizacją przedsięwzięć. Przeprowadzono analizę możliwości łagodzenia skutków tkwiących w procedurze OOS. Omówiono istotę łagodzenia skutków zarówno w odniesieniu do systemu zarządzania przestrzenią, jak i systemu ocen oddziaływania na środowisko. Zaprezentowano hierarchię łagodzenia...
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Characteristics of the polarised off-body channel in indoor environments
PublicationThis paper addresses the depolarisation effect in off-body body area networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Characteristics of the Polarised Off-Body Channel in Indoor Environments
PublicationThis paper addresses the depolarisation effect in off-body Body Area Networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Acoustic Sensing Analytics Applied to Speech in Reverberation Conditions
PublicationThe paper aims to discuss a case study of sensing analytics and technology in acoustics when applied to reverberation conditions. Reverberation is one of the issues that makes speech in indoor spaces challenging to understand. This problem is particularly critical in large spaces with few absorbing or diffusing surfaces. One of the natural remedies to improve speech intelligibility in such conditions may be achieved through speaking...
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The Caucasian flora: a still-to-be-discovered rich source of antioxidants
PublicationCellular redox homeostasis is a state of balance between the formation of Usually Reactive Oxygen and / or Nitrogen Species (ROS/RNS), endogenous antioxidant defence systems, and exogenous dietary antioxidants. The disturbance of redox homeostasis, by the overproduction of endogenous ROS/RNS, may increase the risk of development of so-called civilisation diseases. The solution seems to be either the increased production of endogenous...
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User experience evaluation study on the quality of 1K, 2K, and 4K H.265/HEVC video content
PublicationNowadays, most content creators focus on distributing rich media at the highest possible resolution. Currently, the majority of sold consoles, media players, computer hardware, as well as displays and TVs are advertised as 4K-compatible. The same trend is observed in the case of popular online streaming services and terrestrial TV broadcasts. Generally speaking, it is assumed that higher bitrates provide higher subjective judgements....
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Effects of surface texturing and kind of lubricant on the coefficient of friction at ambient and elevated temperatures
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ANALYSIS OF ENERGY EFFICIENCY IN ELECTRIC DRIVES
PublicationIn this paper energy efficiency in electric drives is analysed. This factor strongly depends on energy parameters - efficiency n and power factor k (in special case cos fi)
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A concept of using static gps masurements for determination of vertical and horizontal land deformations in the main and old city of Gdańsk
PublicationArtykuł opisuje koncepcję wykorzystania statycznych pomiarów GPS (stacje GPS) przy analizie przemieszczeń gruntu na terenie Głównego i Starego Miasta w Gdańsku.
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Jerzy Demkowicz dr inż.
People