Search results for: OPEN-CHANNEL FLOW - Bridge of Knowledge

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Search results for: OPEN-CHANNEL FLOW

Search results for: OPEN-CHANNEL FLOW

  • Considerations of Adaptive Digital Communications in Underwater Acoustic Channel

    Publication

    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,...

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  • Sławomir Jerzy Ambroziak dr hab. inż.

    Sławomir J. Ambroziak was born in Poland, in 1982. He received the M.Sc., Ph.D. and D.Sc. degrees in radio communication from Gdańsk University of Technology (Gdańsk Tech), Poland, in 2008, 2013, and 2020 respectively. Since 2008 he is with the Department of Radiocommunication Systems and Networks of the Gdańsk Tech: 2008-2013 as Research Assistant, 2013-2020 as Assistant Professor, and since 2020 as Associate Professor. He is...

  • Effect of asymmetric fluid flow distribution on flow boiling in a microchannel heat sink – An experimental investigation

    Publication

    - APPLIED THERMAL ENGINEERING - Year 2022

    Flow boiling in microchannels is emerging as an exclusive cooling solution for miniaturized high-power electronic devices alongside having other high heat flux applications. Size miniaturization at microscale strangely increases heat transfer performance as well as flow boiling instabilities. Many flow boiling instabilities are interrelated and result from imperfect hydrodynamic conditions. One of such problems is flow maldistribution among...

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  • Assessment of the Accuracy of a Virtual Multi-Channel Temperature Measuring Instrument

    Publication

    The multi-channel temperature measurement system developed works with NTC thermistors. The article presents the results of theoretical and empirical evaluation of accuracy obtained in measurement channels. The basis for the theoretical assessment is the mathematical model for each of the measurement channels and the characteristics of the system elements included in the circuits of the measurement channel. Two different methods were...

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  • Uncertainty of the liquid mass flow measurement using the orifice plate

    Publication

    The article presents an estimation of measurement uncertainty of a liquid mass flow using the orifice plate. This subject is essential because of the widespread use of this type of flow meters. Not only the quantitative estimation but also the qualitative results of those measurements are important. To achieve these results the authors of the paper propose to use the theory of uncertainty. The article shows the analysis of the...

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  • Sustainability of Cluster Organizations as Open Innovation Intermediaries

    Publication

    The purpose of the paper is to identify the most important open innovation practices used by cluster organizations (COs). To reflect these practices, the paper uses the concept of the trajectory of relationship development in COs, applied in the Interizon cluster organization. Additionally, this paper introduces the potential sustainability-related implications of open innovation adoption in cluster organizations. An in-depth direct...

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  • Towards Open Research Data in the Economics Discipline

    Publication

    Nowadays, Open Research Data, as one of the three pillars of Open Science (along with Open Access and Open Scholarly Communication), is gaining enormous attention from different academic and commercial environments. A wide range of scientific disciplines represent and produce different types of data and at the same time, gather different issues and problems in terms of sharing and dissemination research output. This chapter aims...

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  • Characteristics of the Polarised Off-Body Channel in Indoor Environments

    Publication

    - Year 2016

    This 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...

  • Fluid-flow machinery - Wykład

    e-Learning Courses
    • J. Głuch

    Student poznaje zasady funkcjonowania maszyn wirnikowych, ich rolę w układach energetycznych   Basic knowledge of turbomachinery principle of operation and turbomachinery enrgy power plants

  • Innovation by proxy – clusters as ecosystems facilitating open innovation

    Open innovation is a concept, whose attributes can be perceived as naturally complementing the proximity-based offer of clusters. The purpose of this paper is to investigate the potential role of clusters as intermediaries of open innovation for cluster members. A literature review and an exploratory study were performed, involving in-depth interviews with experts in the field of innovation and clusters in Poland. This article...

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  • Multi-Channel Virtual Instrument for Measuring Temperature—A Case Study

    Publication

    - Electronics - Year 2023

    The article presents the hardware and software configuration of the developed multi-channel temperature measurement system as well as calibration procedures and measurement results verifying the properties of measurement channels. The system has been developed and dedicated primarily for measuring the temperature distribution in a laboratory model simulating underground power lines. With the adopted configuration of the analog...

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  • Adaption of Open Science Paradigm at Gdańsk University of Technology

    Publication

    Open Access plays growing role in sharing results of today's research. The movement is very strong and many Universities, including Gdańsk University of Technology, are adapting this approach. This paper presents general information about Open Access movement and the approach adapted by the Gdańsk University of Technology. The components of Open Science platform as well as the procedures are described.

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  • LABORATORY STAND FOR INVESTIGATIONS OF THE QUICK - CHANGING TEMPERATURE OF GAS FLOWING IN THE PISTON COMPRESSOR OUTLET CHANNEL

    Publication

    This paper presents a laboratory stand, created as a part of work on the doctor dissertation, intended for investigation of heat and flow processes taking place in the Espholin H3S piston compressor outlet channel. The test stand elements and their configuration within the stand are described. Discussed are also problems connected with the quick-changing measurement technique, solutions which have been proposed so far in that technology...

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  • DATA INTEROPERABILITY AND THE OPEN DATA ECOSYSTEM: ROLES AND RESEARCH AREAS

    Publication

    - Year 2023

    Sustainability and value-creation are considered important parameters to measure the success of an open data system. Unfortunately, existing open data systems are not meeting their promises to achieve a sustainable and value-based open data system. Van Loenen et al. (2021) proposed a sustainable and value-creating open data ecosystem. According to their study, the open data ecosystem needs to be user-driven, inclusive, circular,...

  • Wideband Channel Measurements for Polarised Indoor Off-Body Communications

    Publication

    - Year 2018

    This paper presents the initial results of wideband channel measurements for polarised off-body communication at 5.8 GHz, in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of the wearable antenna, and repeated for vertical and horizontal orientations of the off-body one. Four types of measurement scenarios were considered in order to investigate the influence...

  • Measurement of Impulse Response of Shallow Water Communication Channel by Correlation Method

    Performances of underwater acoustic communication (UAC) systems are strongly related to specific propagation conditions of the underwater channel; conditions that can additionally change in time due to the movement of the acoustic system transmitter and receiver or to reflection by underwater objects of the transmitted signal. The time-varying impulse response is a comprehensive description of dynamically changing transmission...

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  • Influence of soil anisotropic stiffness on the deformation induced by an open pit excavation.

    In this paper, the problem of deformation induced by an open pit excavation in anisotropic stiff soils is analysed by FE modelling. The presented research is focused on the influence of material model with anisotropic stiffness on the accuracy of deformation predictions as compared with the field measurements. A new hyperelastic-plastic model is applied to simulate anisotropic mechanical behaviour of stiff soils. It is capable...

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  • Numerical methods in heat and fluid flow, PG_00057408

    e-Learning Courses
    • P. Ziółkowski

    Reiteration of information on thermodynamic cycles and extension of information on their modelling using commercial software tools. Presentation of balances, constitutive equations, how to set up conditions in CFD type codes. Equipment regulation and control in the context of heat exchangers.Presentation of the computational capabilities of the CFD calculation code ANSYS Fluent. Mass, momentum and energy balances in 0D and 3D terms.Analysis...

  • ECHOES REDUCTION DURING DIGITAL DATA TRANSMISSION IN HYDROACOUSTIC CHANNEL – LABORATORY EXPERIMENT

    Publication

    - Year 2019

    The possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections...

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  • Cocoon - najnowsze technologie Open Source.

    Publication

    Cocoon jest projektem rozwijanym w ramach fundacji Apache, która stała się symbolem wysokiej jakości systemów Open Source. Środowisko to umożliwia łatwe budowanie zaawansowanych serwisów WWW opartych na XML przez całe zespoły osób bez problemów wchodzenia w swoje kompetencje. W pracy przedstawiono doświadczenie wykorzystania tego środowiska do budowy portali usług informacyjnych oraz oszacowanie charakterystyki wydajności.

  • Experimental investigations on condensation in flow of HFE-7100 in small diameter channels

    In the paper the authors present investigations of flow condensation with the use of the HFE-7100 as a working fluid. The original and new approach to removing the heat from the channel was applied. The research was carried out using a wide-range real time observations, e.g. using infrared camera and stroboscope microphotography. This paper presents the details of experiment as well as the influence of heat and flow parameters...

  • The Modern Agora for Building the Open Society

    Publication

    - Year 2015

    • sekretarz naukowo-organizacyjny - organizacja międzynarodowej konferencji “The Modern Agora for Building the Open Society ” we współpracy z Europejskim Centrum Solidarności, 02.06.2015 pod patronatem ISOCARP, International Society of City and Regional Planners orazTowarzystawa Urbanistów Polskich TUP/Gdansk. Przy udziale przedstawicieli następujących uczelni: Politechnika Śląska, Fachhochshule Erfurt/ Germany, Mimar...

  • Application of Diversity Combining with RLS Adaptive Filtering in Data Transmission in a Hydroacoustic Channel

    Publication

    - SENSORS - Year 2020

    When transmitting data in a hydroacoustic channel under difficult propagation conditions, one of the problems is intersymbol interference (ISI) caused mainly by the effect of multipath propagation. This phenomenon leads to a decrease in transmission parameters, and sometimes completely prevents it. Therefore, we have made an attempt to use diversity combining with Recursive Least Squares (RLS) adaptive filtering to improve the...

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  • FLOW TURBULENCE AND COMBUSTION

    Journals

    ISSN: 1386-6184 , eISSN: 1573-1987

  • FLOW MEASUREMENT AND INSTRUMENTATION

    Journals

    ISSN: 0955-5986 , eISSN: 1873-6998

  • Journal of Flow Chemistry

    Journals

    ISSN: 2062-249X , eISSN: 2063-0212

  • Adaption of Open Science Paradigm at Gdańsk University of Technology

    Publication

    - Year 2016

    The paper describes the basic principles standing behind Open Access and will try to dispel the doubts behind them. Further the solution adapted by the Gdańsk University of Technology is presented. Later on the systems that the University uses and means of their integration into a complex Open Science platform are described. Finally the procedures needed to publish a document in the repository alongside the University's policy...

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  • Reduction of the Multipath Propagation Effect in a Hydroacoustic Channel Using Filtration in Cepstrum

    Publication

    - SENSORS - Year 2020

    During data transmission in a hydroacoustic channel, one of the problems is the multipath propagation effect, which leads to a decrease in the transmission parameters and sometimes completely prevents it. Therefore, we have attempted to develop a method, which is based on a recorded hydroacoustic signal, that allows us to recreate the original (generated) signal by eliminating the multipath effect. In our method, we use cepstral...

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  • Pressure drop of HFE7000 and HFE7100 during flow condensation in minichannels

    Attention is focused on the issues of flow resistance and pressure drop of perspective refrigeration fluids during condensation in the two-phase flow in minichannels. The case of the flow through a cylindrical single channel of 2.3 mm inner diameter was carefully analyzed. Pressure drop tests have been performed in diabatic flow conditions. The effect of heat flux, mass flux, vapour quality and saturation temperature on the two-phase...

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  • A comprehensive review of open data platforms, prevalent technologies, and functionalities

    Publication

    - Year 2022

    Open data can play a crucial role in different sectors of the world,such as government, science, research, technology, culture, andfinance. There are several necessary measures that every organiza-tion needs to consider before opening data. There are three majorsteps to opening the data: (1) Preparation stage, and (2) launchingthe open data initiative (3) In this case, the feedback mechanismstudy such as expand and sustain stage,...

  • Open-source software (OSS) and hardware (OSH) in UAVs

    Publication

    - Year 2020

    The popularity of the Open Source Tool (OST) has expanded significantly. This is the case for Unmanned Aerial Vehicles (UAVs) based on open-source hardware (OSH) as well. Open-source software (OSS) and OSH can be applied in a wide range of applications and can improve several technologies. The chapter begins with an introduction to OSS depicting its rationale, description of fundamental differences between OSS and proprietary software...

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  • Journal of Receptor Ligand and Channel Research

    Journals

    ISSN: 1178-699X

  • Ograniczenia i koszty wdrożenia systemu open data

    Publication

    - Year 2021

    Przedstawienie kosztów i ograniczeń wdrażania open data w polskich urzędach miejskich.

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  • Analysis of unsteady flow forces on the thermowell of steam temperature sensor

    Publication
    • S. Kornet
    • D. Sławiński
    • P. Ziółkowski
    • J. Badur

    - Transactions of the Institute of Fluid-Flow Machinery - Year 2015

    In this paper, 3D numerical analysis of unsteady flow forces acting on the measuring sheath of steam temperature is presented. According to that purpose, the CFD (Computation Fluid Dynamic [1]) approach has been used. The nonstationary of fluid acting on the measuring sheath such as: Strouhal frequency, amplitude of pressure, structure of vortex, peak of pressure, field of pressure, field of velocity etc. are studied analytically...

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  • Berkeley Open Infrastructure for Network Computing

    Publication

    - Year 2012

    Zaprezentowano system BOINC (ang. Berkeley Open Infrastructure for Network Computing) jako interesujące rozwiązanie integrujące rozproszone moce obliczeniowe osobistych komputerów typu PC w Internecie. Przedstawiono zasadę działania opisywanej platformy. W dalszej części zaprezentowano kilka wybranych projektów naukowych wykorzystujących BOINC, które są reprezentatywne w zakresie zastosowania systemu w ujęciu założonego paradygmatu...

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  • Graphene field-effect transistor application for flow sensing

    Publication

    - EPJ Web of Conferences - Year 2017

    Microflow sensors offer great potential for applications in microfluidics and lab-on-a-chip systems. However, thermal-based sensors, which are commonly used in modern flow sensing technology, are mainly made of materials with positive temperature coefficients (PTC) and suffer from a self-heating effect and slow response time. Therefore, the design of novel devices and careful selection of materials are required to improve the overall...

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  • On some open questions for Ramsey and Folkman numbers

    Publication
    • S. Radziszowski
    • X. Xiaodong

    - Year 2016

    We discuss some of our favorite open questions about Ramsey numbers and a related problem on edge Folkman numbers. For the classical two-color Ramsey numbers, we first focus on constructive bounds for the difference between consecutive Ramsey numbers. We present the history of progress on the Ramsey number R(5,5) and discuss the conjecture that it is equal to 43.

  • Experimental investigations on pressure drop during the condensation in flow of HFE7000 in vertical minichannel

    In the work presented in the paper authors focused attention on the issues of flow resistance and pressure drop during condensation in the flow. The case of the descending flow through a cylindrical single-channel of 2.3 mm inner diameter was carefully analyzed. In the course of investigations a new working fluid HFE 7000 has been scrutinised which has a strongly differing properties in comparison to the other fluids that are commonly...

  • ADAPTIVE IDENTIFICATION OF TIME-VARYING IMPULSE RESPONSE OF UNDERWATER ACOUSTIC COMMUNICATION CHANNEL

    Publication

    The transmission properties of underwater acoustic communication channel can change dynamically due to the movement of acoustic system transmitter and receiver or underwater objects reflecting transmitted signal. The time-varying impulse response measurement and estimation are necessary to match the physical layer of data transmission to instantaneous channel propagation conditions. Using the correlative measurement method, impulse...

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  • Cylindrical orifice testing in laminar flow with the orifice diameter ratio β = 0.5

    Publication

    The paper presents the results of an experimental study of a cylindrical orifice with the orifice diameter ratio β = 0.5 and the flow opening length‑to‑diameter ratio L/d = 1, with hydraulic oil flowing in the DN50 measuring channel. The measurements of the values characterising the oil flow were made in the laminar flow regime, for the Reynolds numbers ranging between Re = 100 to 950. Based on the experimental tests, standard...

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  • Open Data Capability Architecture - An Interpretive Structural Modeling Approach

    Publication

    - Year 2020

    Despite of increasing availability of open data as a vital organizational resource, large numbers of startups and organizations fail when it comes to utilizing open data effectively. This shortcoming is attributable to the poor understanding of what types of capabilities are required to successfully conduct data related activities. At the same time, research on open data capabilities and how they relate to one another remains sparse....

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  • Move into the open space – what can we expect from moving artistic interventions to open urban spaces?

    Publication

    - Interaction Design & Architecture(s) - Year 2017

    The paper discuses the role of incorporating creative engagement into the processes of urban and social development using cultural means of action and expression and the potential of artistic interventions in public space. The block of initiatives within the People’s Smart Sculpture EU project, realized by Gdańsk City Gallery, has been named “Move Into The Open Space”. This paper will provide...

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  • Massive Open Online Courses: strategies and research areas

    Publication
    • J. Murphy
    • N. Sabatini
    • A. Williams
    • P. Ryan
    • L. Cantoni
    • L. Horton-tognazzini

    - Journal of Hospitality & Tourism Education - Year 2014

    The latest education revolution, the massive open online courses (MOOCs), is gaining momentum, accolades, and participation across industry and academia. These learning laboratory behemoths host and assess tens to hundreds of thousands of students in a single class, for free. Similar to their scope, MOOCs’ short- and long-term educational implications seem massive. Immediate MOOC educational outcomes vary widely from roaring successes...

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  • Channel Impulse Response Measurements at mmWave Band in Office and Conference Rooms

    Publication

    In this paper, the measurements of the channel impulse response at mmWave band in office and conference rooms are described. The central frequency is 27 GHz with a bandwidth of 400 MHz. The description of the used measurement stand and considered environments are presented. The initial analysis of the power delay profile, mean delay, and RMS delay spread allows preliminary conclusions to be drawn that there is a significant impact...

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  • Open Strategy for Digital Business. Managing in ICT-Driven Environments

    Publication

    - Year 2024

    This book offers the reader a novel perspective on how digital contexts and open strategy approaches – the act of opening up strategic initiatives beyond company managers to involve front-line employees, stakeholders, and entrepreneurs – are related. Going beyond the claim that digital media drives open strategy by containing a detailed analyses of the interrelations between the two, the authors examine how ICT have diffused globally...

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  • Non-adiabatic Effects in Pressure Drop Calculations in Flow Boiling and Flow Condensation in Minichannels

    Publication

    - Year 2011

    Considerations presented in the paper relate both to the case of flow boiling and flow condensation in conventional channels as well as small diameter ones. Authors devoted all the possible attention that the modeling presented is applicable to the whole range of quality variation in both cases of condensation and boiling. The form of two-phase flow multiplier, which is a major factor in modeling presented here, should be capable...

  • Vacuum Rabi oscillation in nonzero-temperature open cavity

    Porównania teorii oscylacji Rabiego z eksperymentem [M. Wilczewski, M. Czachor, Phys. Rev. A 79, 0333836 (2009)] sugerują, że parametry wnęki doświadczeniu z dużą ilością fotonów mogą być znacznie mniejsze niż te otrzymane dla stanów prawie próżniowych. W tym kontekście pokazujemy, że wniosek pozostaje bez zmian, nawet jeśli do opisu stanu początkowego wnęki zastosuje się bardziej realistyczny opis.

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  • The Importance of Open Access Journals in the Area of Public Health

    Publication
    • M. Schlegel-Zawadzka
    • A. Prusak

    - Public Health - Open Journal - Year 2016

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  • CFD analysis of fluid flow through the labyrinth seal

    Steam and gas turbines are some of the fundamental means of power generation. The energy efficiency of the turbines, however, is not satisfactory. Ever since the start-up of the first turbine in the world, engineers have been striving for their increased efficiency. Multiple solutions to the problem of steam loss in an operating turbine are available. The use of seals is one of them. Empirical methods or numerical calculations...

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  • Source and Channel Coding in Radio Communication Systems

    e-Learning Courses
    • A. Marczak
    • M. Gajewska