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Wyniki wyszukiwania dla: FLOATING POWER PLANT

  • Modular power converter topologies for energy storage and electric power distribution systems

    Publikacja

    - Rok 2017

    This paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. In order to achieve scalability of the system a modular approach is proposed. In addition to this different configuration of the system are analyzed, where depending on requirements and application a scalability in power, in energy capacity of energy storage resource and both in power and...

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  • Swarm-Assisted Investment Planning of a Bioethanol Plant

    Publikacja

    Bioethanol is a liquid fuel for which a significant increase in the share of energy sources has been observed in the economies of many countries. The most significant factor in popularizing bioethanol is the profitability of investments in construction of facilities producing this energy source, as well as the profitability of its supply chain. With the market filled with a large amount of equipment used in the bioethanol production...

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  • Enhancement of lift and drag performances of a NACA0012 airfoil by multi-DBD plasma actuator with additional floating interelectrodes

    Publikacja
    • A. Leroy
    • P. Audier
    • J. Podlinski
    • A. Berendt
    • D. Hong
    • J. Mizeraczyk

    - Rok 2012

    It is clear that the improvement of aircraft aerodynamic performances is currently and will continue to be a significant area of research for the aeronautical industry. The current study is focused on theenhancement of aerodynamic airfoil performances by using a multi-DBD plasma actuator mounted around the model leading-edge. Experiments have been conducted at the University of Orleans, in the 2 m x 2 m test section of a large...

  • Regulation of Plant Microprocessor Function in Shaping microRNA Landscape

    Publikacja
    • J. Dolata
    • M. Taube
    • M. Bajczyk
    • A. Jarmolowski
    • Z. Szweykowska-Kulinska
    • D. Bielewicz

    - Frontiers in Plant Science - Rok 2018

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  • Performance analysis of power swing blocking feature in ABB 670 series impedance relays

    Publikacja

    - Acta Energetica - Rok 2012

    This paper presents test results of a distance protection’s PSD power swing detection feature in ABB 670 series relays. A RED670 relay was tested, which is part of the hydroelectric set protection in Żarnowiec Pumped Storage Plant. The power swing blocking feature’s performance was analysed on the basis of the results of object tests made with an Omicron digital tester. Also presented are simulation results that illustrate the...

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  • Power System Stabilizer as a Part of a Generator MPC Adaptive Predictive Control System

    Publikacja

    - ENERGIES - Rok 2021

    In this paper, a model predictive controller based on a generator model for prediction purposes is proposed to replace a standard generator controller with a stabilizer of a power system. Such a local controller utilizes an input-output model of the system taking into consideration not only a generator voltage Ug but also an additional, auxiliary signal (e.g., α, Pg, or ωg). This additional piece of information allows for taking...

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  • A novel approach to energy safety improvement in the marine power plants with active power surge compensator

    Publikacja

    - Rok 2016

    Paper raises a point of power surges and theirs adverse effects in the marine power plants. The article explains a source of surges appearance, and presents measurements carried out on a modern ship. It discusses effects of dynamic power transients on the ship’s energy safety. Finally it proposes, a novel approach for power surge elimination, based on medium voltage active conditioner. As well as it propose the topology and control...

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  • MARKAL long-term power generation scenarios for Poland - Concept of the model

    Publikacja

    In this paper we have presented the concept of Polish MARKAL optimization model developed for the needs of power generation scenarios in long-term perspective i.e. by 2040. The depiction of Polish MARKAL with Reference Energy System structure was provided. In addition, basic model assumptions, energy technology database, projections of electricity demand and power plant ageing pathways were presented. Our goal is to test MARKAL...

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  • Oversizing the photovoltaic generator capacity in a micro photovoltaic plant

    Publikacja

    A significant part of photovoltaic micro installations in Poland is characterized by photovoltaic generator oversizing in relation to the inverter. The idea of oversizing, however, still raises doubts among some plant owners. In the paper, the energy yield of installation with an oversized and not oversized photovoltaic generator is presented on selected examples, showing the legitimacy of oversizing.

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  • Solutions of Power Electronics Converter for the Shore - to - Ship Power Systems

    W artykule poruszono tematykę zasilania statków zacumowanych w porcie z lądowej sieci elektroenergetycznej poprzez wykorzystanie nowoczesnych konstrukcji przekształtników energoelektronicznych. Zaproponowano budowę sieci dystrybucyjnej prądu stałego, przewoźnej platformy zasilającej oraz zastosowanie zasobników energii

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  • On power stream in motor or drive system

    Publikacja

    In a motor or in a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or a drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load. But the picture of power stream in a motor or in a drive system is presented in the literature in the form of traditional Sankey...

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  • Active Power Quality Controllers

    Publikacja

    - Rok 2008

    Dynamic Static Synchronous Compensator is the most important controller for distribution networks and probably in SEEN. It has been widely used since the 1990s to regulate system voltage precisely, improve voltage profile, reduce voltage harmonics, reduce transient voltage disturbances and load compensation. Rather than using conventional capacitors and inductors combined with fast switches, the D-STATCOM uses a power-electronics...

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  • A design concept of fire protection system for an ecological floating dock

    Publikacja

    - Rok 2005

    W artykule przedstawiono możliwe do wystąpienia na doku pływającym zagrożenie pożarowe oraz projekt koncepcyjny systemu zabezpieczenia przeciwpożarowego. Projekt ten obejmuje: istalację gaśniczą wodno-hydrantową i pianową do ochrony pokładu głównego oraz instalację CO2 do ochrony siłowni, rozdzielni elektrycznej i tunelu kablowego, a także instalację wykrywania i sygnalizacji pożaru.

  • Agent-Based Approach to RBF Network Training with Floating Centroids

    Publikacja

    - Rok 2012

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  • Fixed roof to shell connection in tank with an internal floating cover.

    Publikacja

    - Rok 2003

    Referat dotyczy projektowania połączenia dachu stałego zbiornika walcowego z płaszczem w przypadku zastosowania wewnętrznego przekrycia pływającego. Zaproponowano zastosowanie dodatkowego pierścienia usztywniającego, zabezpieczającego górną krawędź płaszcza zbiornika. Wyniki analiz z zastosowaniem metody elementów skończonych zamieszczono w formie map naprężeń.

  • INCREASING POWER SUPPLY SAFETY IN THE ASPECT OF SUPPORTING THE RENEWABLE ENERGY SOURCES BY CONVENTIONAL AND VIRTUAL POWER STORES

    This paper presents characteristics and purposefulness of supporting the renewable energy sources (OZE) by means of energy stores. The main emphasis was placed on analysis of virtual energy stores available for implementation in Polish economy conditions. A role which management of Demand Side Response (DSR) may play in balancing Polish electric power system, is discussed. Implementation of such solutions together with conventional...

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  • Modular power converter with superconducting magnetic energy storage for electric power distribution system — Analysis and simulation

    Publikacja

    - Rok 2017

    This paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. This paper presents a modular approach of 300 kVA power converter operating with superconducting magnetic energy storage (SMES), which gives high dynamics together with high power and suitable capability for instantaneous energy storage. Analysis and simulation studies of selected power converter...

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  • Power equalization of AES FPGA implementation

    This paper briefly introduces side channel attacks on cryptographic hardware with special emphasis on differential power analysis(DPA). Based on existing countermeasures against DPA, design method combining power equalization for synchronous and combinatorialcircuits has been proposed. AES algorithm has been implemented in Xilinx Spartan II-E field programmable gate array (FPGA) deviceusing the standard and power-equalized methods....

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  • EMI mitigation of GaN power inverter leg by local shielding techniques

    Publikacja

    - IEEE TRANSACTIONS ON POWER ELECTRONICS - Rok 2022

    This paper presents local shielding techniques applied to a half-bridge inverter leg with the aim to reduce the common mode (CM) current noise at converter’s DC input. The research study is conducted for 650V Enhancement mode Gallium Nitride (GaN) power transistor switches. Main contributors of parasitic capacitances referred to the inverter-leg middle point node are identified. Then, shielding solutions are proposed to reduce...

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  • Activity coordination of capacitor banks and power transformer controllers in order to reduce power losses in the MV grid

    Publikacja

    One of the main issues related to the optimization of the MV (middle voltage) network is to reduce losses of active and reactive power. Lower losses of active and reactive power give not only economic advantage, but also improvement of energy quality. The object of regulation that can be used for these purposes are transformer with On-Load Tap Changer and capacitor's banks. This paper presents results of analysis of the possibility...

  • Combined Heat & Power Generating Systems

    Publikacja

    - Rok 1988

    Steam cycles in combined heat and power plants. Efficiency of combined heat and power systems. Characteristics of steam-turbine CHP plants. Choice of equipment in CHP generating systems. Economic effects of combined heat and power production. Costs and energy produced CHP generating systems. Future development trends in CHP generating systems.

  • Energy losses in hydrostatic drive:Drive investigation method compatible with diagram of power increase opposite to the direction of power flow

    Publikacja

    - Rok 2016

    Energy losses and efficiency of drive motor must be presented as functions of physical quantities independent of losses in the motor. Such quantities are speed and load required by the driven device, changing in the drive operating field. Speed and load decide of the useful power and, in differentiated way, of kinds and values of losses in the motor. But energy losses and efficiency of drive motors are evaluated as functions of...

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  • Ciliated protozoa in the impact zone of the Uzhgorod treatment plant

    Publikacja
    • V. Pliashechnyk
    • Y. Danko
    • G. Łagód
    • J. Drewnowski
    • T. Kuzmina
    • R. Babko

    - E3S Web of Conferences - Rok 2017

    This paper presents the results of studies on the Uzh River (Ukraine, Zakarpattia Oblast) near the effluent point of a sewage treatment plant in Uzhgorod. The samples were taken at various sites of the treatment plant along the stages of purification process, as well as in the river, at a number of different points above and below the wastewater discharge. At each of these objects, the temperature...

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  • Fault detection in measuring systems of power plants

    Publikacja

    This paper describes possibility of forming diagnostic relations based on application of the artifical neural networks (ANNs), intended for the identifying of degradation of measuring instruments used in developed power systems. As an example a steam turbine high-power plant was used. And, simulative calculations were applied to forming diagnostic neural relations. Both degradation of the measuring instruments and simultaneously...

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  • Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat

    Publikacja

    This paper presents the methodology of techno-economic analysis for a nuclear unit operating in partial cogeneration mode and its application for the case study: a nuclear power plant planned in Poland. The research objectives were: to propose EPR, AP1000 and ESBWR nuclear condensing-extraction turbine systems modifications required for operation in cogeneration, to determine optimal heat production and heat transport line (HTL)...

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  • The paradigms of power in the Russian Federation

    Publikacja

    - Rok 2011

    This article outlines the position of the Russian Federation in the first decade of the 21th century, seen in its political, economic and military aspects. It attempts to document the fact that Russia, the former world superpower, has turned into a regional power.

  • The investment process in the power supply industry

    Publikacja

    - Rynek Energii - Rok 2012

    The basis for power supply industry programming in a market economy should be the principle of sustainable development, which must take into account maintaining an adequate level of energy security on the one hand, and the aim to preserve the maximum degree of non-renewable resources on the other hand. Therefore, the overriding aim should be a strive to meet the current and prospective demand for energy and fuel, in conjugation...

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  • Virtual inertia in Electric Power System

    The article presents the idea of introducing virtual inertia system to the electric power systems. The virtual inertia aim is to reduce or eliminate the effect of reducing the inertia of the power system as a result of replacing classic electricity generating units with renewable renergy sources (RES). The considerations are ilustrated by a computational example.

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  • Installation of Compensators in the Power System Transmission Grid

    Publikacja

    - Acta Energetica - Rok 2019

    The article discusses issues of reactive power compensation in transmission grids, with particular focus on the selection of compensator locations and basic parameters. Attention was focused on modern power electronics systems that ensure full automatic compensator adjustment to voltage or power criteria.

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  • Partial characterization of indigo (Polygonum tinctorium Ait.) plant seeds and leaves

    Publikacja
    • B. Heo
    • H. Jang
    • J. Y. Cho
    • J. Namieśnik
    • Z. Jastrzębski
    • K. Verasilp
    • G. Gonzalez-Aquilar
    • A. L. Martinez-Ayala
    • M. Suhaj
    • S. Gorinstein

    - INDUSTRIAL CROPS AND PRODUCTS - Rok 2013

    The aim of this study was to assess the contents of indigo's bioactive compounds, its antioxidant and anticancer activities in acetone, hexane and DMSO extracts and to compare the overall bioactivity with another more used medicinal plant named prolipid. It was found that the contents of the bioactive compounds in the studied extracts from different parts of indigo plant varied (P < 0.05): the significantly highest content of polyphenols...

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  • State equations in the mathematical model of dynamic behaviour of multihull floating unit

    Przedstawiony artykuł dotyczy dynamiki wielokadłubowej jednostki pływającej typu katamaran poddanej wymuszeniom pochodzącym od falowania nieregularnego. Analiza dynamiki jednostki wielokadłubowej została przeprowadzona przy założeniu, że model układu jest modelem liniowym na który działa fala nieregularna. Model matematyczny takiego układu dynamicznego jest reprezentowany poprzez równania stanu. Zapisane zostały równania uwzględniające...

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  • Preliminary analysis of proposed ship docking systems for a designed floating dock

    Publikacja

    W artykule przedstawiono alternatywne koncepcje, wraz z ich analizą porównawczą, urządzeń dokujących statek na doku pływającym. Dok ten projektowany był na Wydziale Oceanotechniki i Okrętownictwa Politechniki Gdańskiej w ramach projektu ECOLOGICAL DOCK E!2968. Zaprezentowane rozwiązania różnią się głównie rodzajem zastosowanych w nich urządzeń: w pierwszym przypadku są to przewijarki i wózki dokujące, zaś w drugim - wciągarki...

  • IN VITRO PROPAGATION OF RHODODENDRON TOMENTOSUM - AN ENDANGERED ESSENTIAL OIL BEARING PLANT FROM PEATLAND

    Publikacja

    - ACTA BIOLOGICA CRACOVIENSIA SERIES BOTANICA - Rok 2016

    Rhododendron tomentosum Harmaja (formerly Ledum palustre L.) is a medicinal peat bog plant native to northern Europe, Asia and North America. This plant has a distinctive aroma thanks to the presence of essential oil, to which it also owes its anti-inflammatory, analgesic, antimicrobial and insecticidal properties. However, in Europe R. tomentosum is classified as an endangered species, mainly due to degradation of peatlands. In...

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  • Analysis of Induced Voltages and Power Losses in High Voltage Power Cables for Selected Methods of Cables Sheaths Bonding

    Power is increasingly supplied to city centres with 110 kV cable lines. This is a convenient way to supply power, and practically the only one possible in areas of dense urban development. A high-voltage cable contains a coaxial metallic sheath, in which in normal operation and in fault conditions (during short-circuits) significant line-to-earth voltages can be induced, which threatens electric shock and/or damage to the cable’s...

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  • SVC and power transformers controllers coordination

    Publikacja

    The use of shunt compensators such as FACTS (for example SVC) in power systems gives possibility of fast and flexible control of voltage or reactive power. An efficient cooperation between a transformer and compensator connected to busbars, or transformer’s tertiary winding, requires a proper coordination of controls. The article contains theoretical considerations and simulation results which indicate that such co-ordination is...

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  • Power System Dynamics. Stability and Control. 3rd edition

    Publikacja

    - Rok 2020

    Comprehensive, state-of-the-art review of information on the electric power system dynamics and stability. It places the emphasis first on understanding the underlying physical principles before proceeding to more complex models and algorithms. The book explores the influence of classical sources of energy, wind farms and virtual power plants, power plants inertia and control strategy on power system stability. The book cover...

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  • Modified Inductive Multi-Coil Wireless Power Transfer Approach Based On Z-Source Network

    Publikacja

    - IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS - Rok 2021

    This article presents a non-conventional approach to a multi-coil wireless power transfer system based on a Z-source network. The novelty of the approach lies in the use of a Z-source as a voltage source for energy transmission through the wireless power transfer coils. The main advantage is in a reduced number of semiconductors. This paper provides the design approach, simulation and experimental study. Feasibility and possible...

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  • New Performance Indices for Power System Stabilizers

    Publikacja

    - ENERGIES - Rok 2022

    The subject of the article is issues related to innovative indices for power system stabilizers (PSSs). These new indices will be able to quickly show which PSS (among many other PSSs) is not working properly and that advanced optimization and simulation methods should be used to improve the PSS settings. The authors note the fact that the acceptance requirements for PSSs are different in various power systems. Moreover, the authors...

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  • The forming and emission of high power electromagnetic pulses

    Publikacja

    An impulse energy source, a power conditioning system and an electromagnetic field emitter are essential to generate an electromagnetic field pulse (EMFP) with a specific frequency bandwidth. Selected simulation results for a power conditioning system consisting of a fuse opening switch and a paraboloidal electromagnetic emitter have been presented in this article. The synthetic system examined in the simulation is powered by an...

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  • The forming and emission of high power electromagnetic pulses

    Publikacja

    An impulse energy source, a power conditioning system and an electromagnetic field emitter are essential to generate an electromagnetic field pulse (EMFP) with a specific frequency bandwidth. Selected simulation results for a power conditioning system consisting of a fuse opening switch and a paraboloidal electromagnetic emitter have been presented in this article. The synthetic system examined in the simulation is powered by...

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  • Comparison of AHP and Numerical Taxonomy Methods Based on Biogas Plant Location Analysis

    Publikacja

    The paper presents a comparison of the multi-criteria Analytic Hierarchy Process (AHP) method and numerical taxonomy in biogas plant location selection. Biogas plants are sources that will significantly contribute to the implementation of the provisions of the energy and climate package for Poland by 2030. Increasing the share of energy produced from renewable sources, e.g. biogas plants, will increase the country’s energy security....

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  • Identifying and Mitigating the Negative Effects of Power in Organizations

    This article investigates the possible negative effects of power in organizations. It demonstrates how holding power may affect an individual’s perception of others, actions, and cognition. Ways in which power may have a detrimental effect on different aspects of a manager’s functioning within an organization, including building relationships, communication, and performance are analyzed. It is argued that individuals are unaware...

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  • Security Information Sharing for the Polish Power System

    Publikacja

    - Rok 2015

    The Polish Power System is becoming increasingly more dependent on Information and Communication Technologies which results in its exposure to cyberattacks, including the evolved and highly sophisticated threats such as Advanced Persistent Threats or Distributed Denial of Service attacks. The most exposed components are SCADA systems in substations and Distributed Control Systems in power plants. When addressing this situation...

  • Symmetrical power line conditioner - basic properties

    Publikacja

    - Rok 2005

    In this paper the basis of analytical modelling of the UPQC arrangements (Unified Power Quality Conditioner) in d-q rotating coordinates, as well as select results of investigations conducted on the simplified small power laboratory model, were talked over. In short form power balance as well as fundamental dependences and analytical model with regard of decoupling circuits, were investigated. Applied method for DC link capacitance...

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  • Chemical composition, antioxidant and anticancer effects of the seeds and leaves and indigo (polygonum tinctorium Ait.) Plant

    Publikacja
    • H. Jang
    • B. Heo
    • Y. S. Park
    • J. Namieśnik
    • D. Barasch
    • E. Katrich
    • K. Vearasilp
    • S. Trakhtenberg
    • S. Gorinstein

    - APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY - Rok 2012

    Seeds and leaves of indigo (Polygonum tinctorium Ait.) plant were investigated and compared with another medicinal plant named prolipid for their properties such as chemical composition, antioxidant, and anticancer effects by Fourier transform infrared, three-dimensional fluorescence spectroscopy, and electrospray ionization-MS in negative mode. It was found that polyphenols, flavonoids, and flavanols were significantly higher...

  • Evaluation of technical efficiency of heat and electric power generation

    Publikacja

    - Polish Maritime Research - Rok 2009

    This paper presents an evaluation of technical efficiency and time-dependent changes in productivity of Polish professional electric power and heat&electric power stations by using Data Envelopment Analysis non-parametric method. The research covered the enterprises whose total available electric power amounted to about 98% of that of all professional thermal electric power stations in this country. The analysis has concerned...

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  • Voltage control in a power system with renewable sources of energy

    Publikacja

    - Rok 2019

    Intensive development of distributed generation in power systems, caused by the European Union energy policy, gives possibility for improving safety in power delivery as well as optimizing the costs of the systems functioning. In this context, distributed generation can be used for voltage control in power systems – it can be performed by the control of reactive power of each source of energy or a group of energy sources. This...

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  • The Large Customer Reactive Power Control Possibilities

    Publikacja

    n this paper the authors wish to draw attention to the rationale for, and the possibility of, the use of local reactive power sources by the Transmission Node Master Controller (TNMC). Large Customers (LC) are one of the possible reactive power sources. The paper presents the issues related to the need for coordination between the control systems installed in the LC network, and coordination between control systems of the LC as...

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  • Probabilistic concept of defining the situations possible to occur during operation of floating docks

    Publikacja

    - Rok 2005

    W artykule zasygnalizowana została możliwość oszacowania bezpieczeństwa doków pływajacych, w wyniku zastosowania teorii procesów semimarkowskich, zarówno w fazie projektowania jak też eksploatacji. Przedstawiono opis formalny sytuacji, jakie mogą zaistnieć podczas funkcjonowania (działania) doków pływających, zarówno budowlanych jak również remontowych. Wyróżniono takie sytuacje jak: normalna, skomplikowana, niebezpieczna, awaryjna...

  • Developing Methodology for Model Tests of Floating Platforms in Low -Depth Towing Tank

    The paper presents two different methods of physical modeling of semi-submersible platform mooring system for research in low depth towing tank. The tested model was made in the scale of 1:100 resembling the "Thunder Horse" platform moored in the Gulf of Mexico at a depth of 1,920 m. Its mooring system consisted of 16 semi-taut mooring lines (chain-wire-chain) spaced starshape and attached at the bottom to suction piles. The tests...

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