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Wyniki wyszukiwania dla: PERFORMANCE-ENERGY OPTIMIZATION

  • Improved Design Closure of Compact Microwave Circuits by Means of Performance Requirement Adaptation

    Publikacja

    - Rok 2021

    Numerical optimization procedures have been widely used in the design of microwave components and systems. Most often, optimization algorithms are applied at the later stages of the design process to tune the geometry and/or material parameter values. To ensure sufficient accuracy, parameter adjustment is realized at the level of full-wave electromagnetic (EM) analysis, which creates perhaps the most important bottleneck due to...

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  • Evaluation of compression realization in diesel engine based on performance indicator changes

    Publikacja

    In the article a method of evaluation of a diesel engine during the realization of processes of working cycle on the example of compression is described. The method is based on the use of the quantity called performance indicator in the description of the engine's work, which contains the information on the energy values, which may be disposed using the engine and the time at which it can be delivered. Theoretical information has...

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  • Losses and energy efficiency of drive motors and systems

    Publikacja

    Losses and energy efficiency of every 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 machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...

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  • Losses and energy efficiency of drive motors and systems

    Publikacja

    - Rok 2013

    Losses and energy efficiency of every 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 machine or device driven by the motor, changing in the drive operating field. Speed and load of the motor decide of the instantaneous useful power of the motor and also in a differentiated way of kinds and values of losses occurring in the...

  • Machine learning for the management of biochar yield and properties of biomass sources for sustainable energy

    Publikacja
    • G. V. Nguyen
    • P. Sharma
    • Ü. Ağbulut
    • H. S. Le
    • T. H. Truong
    • M. Dzida
    • M. H. Tran
    • H. C. Le
    • V. D. Tran

    - Biofuels Bioproducts & Biorefining-Biofpr - Rok 2024

    Biochar is emerging as a potential solution for biomass conversion to meet the ever increasing demand for sustainable energy. Efficient management systems are needed in order to exploit fully the potential of biochar. Modern machine learning (ML) techniques, and in particular ensemble approaches and explainable AI methods, are valuable for forecasting the properties and efficiency of biochar properly. Machine-learning-based forecasts,...

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  • Performance Comparison of a 650 V GaN SSFET and CoolMOS

    The new technology of wide band gap semiconductors is said to outperform up-to-date silicon devices. High voltage Gallium Nitride (GaN) transistors, now emerging in the market, have even three times shorter switching times and even four times smaller energy losses compared to the best in-class Si devices. In this paper the performance of a 650 V GaN SSFET is evaluated and compared with the newest silicon family of CoolMOS™ technology....

  • Technical and economic analysis of energy storage in the compressed air technology with low capacity for the production plant

    Compressed air energy storage (CAES) system is a promising technology due to its numerous advantages, including relatively low maintenance cost, a long lifespan and high operational flexibility. This article explores the possibility of designing a CAES power plant as a source of electricity and heat for an existing industrial plant. The study involves the technical analysis of the power plant parameters and the economic analysis...

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  • Reducing of energy consumption in public transport - results of experimental exploitation of super capacitor energy bank in Gdynia trolleybus system

    Publikacja

    - Rok 2014

    Paper presents the result of test exploitation supercapacitor energy bank in Gdynia trolleybus system. In the first part of the article the basics of the regenerative breaking are presented and the construction and control strategy of the supercapacitor bank are described. The area of research and method of measurement are explained. In the second part of paper the results of tests and measurements are described. Emphasis was placed...

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  • POSSIBILITIES OF ELECTRICAL ENERGY GENERATION IN PHOTOVOLTAIC SYSTEMS INSTALLED IN CENTRAL EUROPE

    Publikacja

    - Rok 2013

    Nowadays, fossil fuels are the main sources of energy from which electricity is obtained. But these sources will not last forever, so in due course renewable energies will have to replace them in this role. One of these new sources is solar energy. To generate electricity from sunlight, solar (photovoltaic - PV) cells and modules are used. The increasing interest in PV cells and modules worldwide is due mainly to the fact that...

  • 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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  • Cu-Doped Layered Double Hydroxide Constructs the Performance-Enhanced Supercapacitor Via Band Gap Reduction and Defect Triggering

    Publikacja

    - ACS Applied Energy Materials - Rok 2022

    Layered double hydroxides (LDHs) are regarded as the excellent electrode materials for supercapacitors because of their high theoretical capacitance and abundance. However, the poor conductivity and limited reaction kinetics of LDHs restrict their practical application severely. Herein, Cu is chosen from groups VIII/IB/IIB as dopants for Co-based LDH (CuCo-LDH). The designed metal–organic framework-derived hierarchical CuCo-LDH...

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  • Improvements and Spatial Dependencies in Energy Transition Measures

    Publikacja

    - ENERGIES - Rok 2021

    This article aims to improve one of the newest energy transition measures—the WorldEconomic Forum WEF Energy Transition Index (ETI) and find its driving forces. This paper proposesa new approach to correct the ETI structure, i.e., sensitivity analysis, which allows assessing theaccuracy of variable weights. Moreover, the novelty of the paper is the use the spatial error modelsto estimate determinants of the energy transition on...

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  • Proposed Amendments to Reactive Energy Billing

    Publikacja

    This paper describes possible amendments to the rules of reactive energy billing in the tariffs in Poland. Modifications in the tariffs to improve their motivational function for distribution system users are identified as the most expedient. New problems arising from distributed generator operations are also indicated. A billing method that can be effectively implemented at the occurrence of distorted voltage and current waveforms...

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  • Stabalization of solar-panel energy system for Pakistani household

    Publikacja

    - Rok 2018

    Renewable energy resources such as Sun and wind are getting popular and easier to use day by day. It is a better method to fulfill our demands as sun is a continuous source of energy for Earth. Many countries are fulfilling their demands by Solar Panels. Solar panel is used as a converter between sunlight and electrical energy. This research paper is going to tell that how to obtain electrical energy from sunlight more efficiently...

  • Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan

    Publikacja

    - Frontiers in Energy Research - Rok 2023

    This study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking these...

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  • Scrutiny of power grids by penetrating PV energy in wind farms: a case study of the wind corridor of Jhampir, Pakistan

    This study examines the problems caused by intermittent renewable energy sources, especially wind farms, and suggests a different solar energy penetration strategy to improve their loading capacity. The study uses real-time data from a wind farm in Jhampir, Pakistan, to analyse and assess various aspects of grid stations connected to wind farms. Electrical Transient Analyzer Program is used to validate the results by linking...

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  • Hybrid electrode materials for fast performance devices

    Energy storage devices such as Electrochemical Double Layer Capacitors and other types of the electrochemical capacitors require chemically stable, non-soluble, electrochemically active electrode materials compatible with appropriate electrolytes. Factors which determine their applicability are derived from so called electrochemical window of electroltes, nature of charge accumulation and their kinetics. On the other hand technological...

  • Recent Advances in Performance-Driven Surrogate Modeling of High-Frequency Structures

    Design of high‐frequency structures, including microwave and antenna components, heavily relies on full‐wave electromagnetic (EM) simulation models. Their reliability comes at a price of a considerable computational cost. This may lead to practical issues whenever numerous EM analyses are to be executed, e.g., in the case of parametric optimization. The difficulties entailed by massive simulations may be mitigated by the use of...

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  • Survey of Methodologies, Approaches, and Challenges in Parallel Programming Using High-Performance Computing Systems

    This paper provides a review of contemporary methodologies and APIs for parallel programming, with representative technologies selected in terms of target system type (shared memory, distributed, and hybrid), communication patterns (one-sided and two-sided), and programming abstraction level. We analyze representatives in terms of many aspects including programming model, languages, supported platforms, license, optimization goals,...

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  • Low energy electron mass stopping power in H2

    Publikacja

    We present experimental mass stopping powers of electrons in gaseous H2 obtained with a newly developed electron time-of-flight spectrometer, for the incident electron energy range of 10eV to 25eV. In our procedure the average energy loss is derived from our conversion of measured electron time-of-flight spectra into equivalent electron energy loss spectra so as to obtain the values of mass stopping power for electron scattering...

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  • Alternative Energy: Photovoltaic Solar Cells

    Publikacja

    Solar radiation is a fuel for photovoltaic cells and modules, which are a source of electric energy. Viable solar technologies that have been developed in the past are starting to be adopted on a broader and more meaningful global scale across different sectors with ever-increasing market penetration. In this entry, a brief overview of the material properties relevant to solar cell operation, the structure of the solar cell, and electrical...

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  • Market knowledge and new product performance: the mediating effects of new product performance

    Market knowledge is recognised as an important predictor of new product performance, which existing studies have proven. However, a missing link in this relationship is creativity, and specifically, as a natural process in product innovation. This study aims to examine a model that includes two mediating mechanisms between market knowledge scope and two new product outcomes, respectively: a new product’s competitive advantage and...

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  • Energy Consumption Modeling in SPMD and DAC Applications

    Publikacja

    - Rok 2016

    In this chapter, we show a study of energy consumption during execution of SPMD and DAC application – the same applications which time of execution we modeled in the previous two chapters. We measured an average power usage at a single node of the GALERA+ cluster during application execution and then we modeled the total energy consumption by the application. Next we simulated the applications using MERPSYS and we compared the...

  • THE CONCEPT AND THE STATE OF RESEARCH ON THE PERFORMANCE OF FAMILY BUSINESSES

    Publikacja

    Purpose: This study's primary goal is to present the theoretical concept of family enterprises. Specifically, the results of earlier studies and the issues facing this field of research now will be described. The article also examines the underlying impacts that family control has on business management in order to fill the research gap left by earlier studies on the performance differences between family and non-family enterprises....

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  • The Energy of Finance in Refining of Medical Surge Capacity

    Publikacja

    - ENERGIES - Rok 2021

    The availability of resources and their concentration in the place of greatest need, will not allow us to successfully overcome a medical surge without the energy required to activate these resources and activities, and increase their quantities if necessary, that is why the staff and management of healthcare institutions are forced to making ethical crisis decisions about who wins and who loses. This study highlights the versatility...

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  • BUILT IN PERFORMANCE EVALUATION FOR AN ADAPTIVE NOTCH FILTER

    Publikacja

    The problem of estimating instantaneous frequency of a non- stationary complexsinusoid (cisoid) buried in wideband no ise is considered. The proposed approach extends adaptive notc h filtering algorithm with a nontrivial performance assessme nt mechanism which can be used to optimize frequency tracking performance of the adaptive filter. Simulation results confi rm that the proposedextension allows one to improveaccuracyo f frequency...

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  • Effectiveness of a dual surface modification of metallic interconnects for application in energy conversion devices

    Publikacja

    - INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Rok 2022

    A dual surface modification of an SOFC metallic interconnect with a Gd2O3 layer and an MnCo2O4 coating was evaluated. The tested samples were oxidized for 7000 h in air at 1073 K. Oxidation products were characterized using XRD, SEM-EDS, and confocal Raman imaging, and ASR was measured. The effect of gadolinium segregation at grain boundaries in Cr2O3 was evaluated using S/TEM-EDS. Area specific-resistance was measured and fuel...

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  • Performance of the domestic micro ORC equipped with the shell-and-tube condenser with minichannels

    Publikacja

    In this paper, the original compact shell-and-tube heat exchanger with circular minichannels of in-house design and manufacturing is presented as the condenser for the domestic micro heat and power plant investigations as well as other future technical applications. The heat exchanger is equipped with turbulizing baffles inside the shell. The shell itself is made of a tubular sleeve having an inner diameter of 0.067 m and the length...

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  • Alternative Energy: Photovoltaic Modules and Systems

    Publikacja

    Use of solar energy does not contribute to global warming. The light-to-current conversion (photovoltaic conversion) takes place within solar cells, which in most cases are made of silicon. Solar module consists of many solar cells, which are electrically connected and placed between glass or Tedlar® and framed by an aluminium frame. A number of solar modules and other components form photovoltaic systems. In this entry, a brief...

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  • Advanced Potential Energy Surfaces for Molecular Simulation

    Publikacja
    • A. Albaugh
    • H. Boateng
    • R. Bradshaw
    • O. Demerdash
    • J. Dziedzic
    • Y. Mao
    • D. Margul
    • J. Swails
    • Q. Zeng
    • D. Case... i 10 innych

    - JOURNAL OF PHYSICAL CHEMISTRY B - Rok 2016

    Advanced potential energy surfaces are defined as theoretical models that explicitly include many-body effects that transcend the standard fixed-charge, pairwise-additive paradigm typically used in molecular simulation. However, several factors relating to their software implementation have precluded their widespread use in condensed-phase simulations: the computational cost of the theoretical models, a paucity of approximate models...

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  • Improved Modeling of Microwave Structures Using Performance-Driven Fully-Connected Regression Surrogate

    Publikacja

    - IEEE Access - Rok 2021

    Fast replacement models (or surrogates) have been widely applied in the recent years to accelerate simulation-driven design procedures in microwave engineering. The fundamental reason is a considerable—and often prohibitive—CPU cost of massive full-wave electromagnetic (EM) analyses related to solving common tasks such as parametric optimization or uncertainty quantification. The most popular class of surrogates are data-driven...

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  • Energy Losses Due to Imperfect Payment Infrastructure and Payment Instruments

    Publikacja

    - ENERGIES - Rok 2021

    One of the strategic objectives of the European Union is a reduction in greenhouse gas emissions and improvement of energy efficiency by at least 32.5% in different areas of the economy by 2030. However, little is known about the impact of payment in retail on energy consumption. The purpose of this paper is to assess the chain of losses of time and energy, and therefore financial losses, that occur due to the imperfection of payment...

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  • Simulator for Performance Evaluation of ASON/GMPLS Network

    Publikacja

    The hierarchical control plane network architecture of Automatically Switched Optical Network with utilization of Generalized Multi-Protocol Label Switching protocols is compliant to next generation networks requirements and can supply connections with required quality of service, even with incomplete domain information. Considering connection control, connection management and network management, the controllers of this architecture...

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  • THE MODELLING OF ACCUMULATION AND DISSIPATION OF ENERGY IN MECHANICAL DRIVE SYSTEM

    Publikacja

    This paper presents a modelling of accumulation and dissipation energy in simple drive system. The simple drive system is presented by laboratory stand designed for calculate fatigue life of material for bending and rotation tests pieces. The laboratory stand was prepared to diagnosis of fatigue life of material by use energetic methods. This idea was submitted as utility model to Polish Patent Office. This laboratory stand gives...

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  • Traffic Type Influence on Performance of OSPF QoS Routing

    Publikacja

    - Rok 2012

    Feasibility studies with QoS routing proved that the network traffic type has influence on routing performance. In this work influence of self-similar traffic for network with DiffServ architecture and OSPF QoS routing has been verified. Analysis has been done for three traffic classes. Multiplexed ON-OFF model was used for self-similar traffic generation. Comparison of simulation results were presented using both relative and...

  • On the use of a charge balancing method for low energy measurements

    The paper presents the method for the estimation of the energy consumption of the low-power microcontroller-based devices. Due to high dynamics of the changes of the supply current of the tested devices during the operational cycle, the consumed energy estimation is not easy. In order to avoid disadvantages of known methods, the charge balancing method was employed similarly like in some types of A/D converters.

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  • HYBRID ENERGY SYSTEM FOR A CLASSIC SHIP POWER PLANT

    Publikacja

    The article presents a brief overview of hybrid energy systems used on ships. The area of their application is outlined. The benefits of using such systems are also indicated. Then, the classic ship power plant is defined. The most important part of the article is a proposal how to modify a classic engine room by using a hybrid energy system. The idea is: to accumulate a part of electricity in areas where it is allowed to burn...

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  • Binder-induced surface structure evolution effects on Li-ion battery performance

    Publikacja
    • J. S. Rezvani
    • M. Pasqualini
    • A. Witkowska
    • R. Gunnella
    • A. Birrozzi
    • M. Minicucci
    • H. Rajantie
    • M. P. Copley
    • F. Nobili
    • A. DiCicco

    - APPLIED SURFACE SCIENCE - Rok 2018

    A comparative investigation on binder induced chemical and morphological evolution of Li4Ti5O12 electrodes was performed via X-ray photoemission spectroscopy, scanning electron microscopy, and electrochemical measurements. Composite electrodes were obtained using three different binders (PAA, PVdF, and CMC) with 80:10:10 ratio of active material:carbon:binder. The electrochemical performances of the electrodes, were found to be...

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  • Traffic Type Influence on Performance of OSPF QoS Routing

    Feasibility studies with QoS routing proved that the network traffic type has influence on routing performance. In this work influence of self-similar traffic for network with DiffServ architecture and OSPF QoS routing has been verified. Analysis has been done for three traffic classes. Multiplexed On-Off model was used for self-similar traffic generation. Comparison of simulation results was presented using both relative and non-relative...

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  • Improvement of Performance Level of Steel Moment-Resisting Frames Using Tuned Mass Damper System

    Publikacja

    - Applied Sciences-Basel - Rok 2020

    In this paper, parameters of the tuned mass dampers are optimized to improve the performance level of steel structures during earthquakes. In this regard, a six-story steel frame is modeled using a concentrated plasticity method. Then, the optimum parameters of the Tuned Mass Damper (TMD) are determined by minimizing the maximum drift ratio of the stories. The performance level of the structure is also forced to be located in a...

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  • The linkage between knowledge risk management and organizational performance

    Publikacja

    - JOURNAL OF BUSINESS RESEARCH - Rok 2019

    The purpose of this study is to examine the effect of knowledge risk management (KRM) on organizational performance, with measures considered as “softer” measures of performance, i.e. innovativeness, responsiveness, sustainability, and agility. Data were collected using an online questionnaire sent to private and public orga- nizations located all over the world. The analysis and hypotheses testing were performed using structural...

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  • Evaluation of ASON/GMPLS Connection Control Servers Performance

    Performance aspects have always been very important in telecommunications, especially in control elements. That problem also regards ASON/GMLPS network, which is one of the propositions for Next Generation Network (NGN) transport stratum. In this paper we investigate performance of ASON/GMPLS Connection Control Servers (CCSs) in laboratory testbed, which architecture and operation are also described. In order to evaluate the performance...

  • Rational Use of Primary Energy in Single-Family Residential Houses

    This work presents results of the primary energy use for heating residential single-family house. Analysis includes domestic hot water system (DHW) and heating, ventilation and air condition system (HVAC). During researches the conventional and alternative energy sources (natural gas, biomass, fuel oil, bituminous coal, lignite or electric energy obtained from electric power system – EPS) were used in DHW and HVAC systems. Furthermore...

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  • CAES – Energy storage providing stability for national power system

    Publikacja

    - Rok 2013

    This paper presents a short characteristics of the power system. It also describes various types of energy storage technologies. The suggested solution of accumulation and generation of electric power is based on the cooperation of gas turbine with Compressed Air Storage Energy systems – CAES. This analysis describes also various types of cooperation of CAES and renewable sources of energy, particularly wind power systems.

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  • An analysis of solar energy conversion systems based on photon and thermal processes

    Publikacja

    Solar spectral irradiance covers a fairly broad wavelength range. Solar radiation is part of the electromagnetic spectrum which is described by the concept of wave-particle duality. The corpuscular theory of electromagnetic radiation states that energy is transmitted by photons. Photons carry specific amounts of energy which can be used to convert solar energy into other types of energy, in particular electricity. The internal...

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  • Reactive Energy Billing in Operator Tariffs in Poland

    Publikacja

    The paper describes the current method of reactive energy billing in the tariffs of distribution grid operators in Poland. The current solutions are subject to critical assessment. Issues related to the motivation effect of the current solutions on consumers are analysed. Problems that occur in relation with connecting distributed generators to the distribution grid and challenges related to prosumer billing are indicated.

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  • Study on effective front region thickness of PCM in thermal energy storage using a novel semi-theoretical model

    Publikacja

    Thermal energy storage in mobile applications, particularly battery of electric vehicles, is currently gaining a lot of importance. In this paper, a semi-theoretical time-dependent mathematical model of the phase change in a double shell thermal energy storage module has been developed where the inner tube is a heat exchange surface. An effective front region thickness for the melting and solidification process has been studied....

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  • Price Changes in Wholesale Market of Electrical Energy in Poland

    The article discusses the Price changes on the wholesale electricity market in Poland Moreover, The price levels on the futures electricity markets and the spot transactions market are presented. The impact of emission charges under the EU ETS on the price of electricity in the domestic market has been taken into consideration Furthermore, the basic determinants of the generation structure in Poland that influence the level of...

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  • Gossiping by energy-constrained mobile agents in tree networks

    Publikacja

    - THEORETICAL COMPUTER SCIENCE - Rok 2021

    Every node of an edge-weighted tree network contains a data packet. At some nodes are placed mobile agents, each one possessing an amount of energy (not necessarily the same for all agents). While walking along the network, the agents spend the energy proportionally to the distance traveled and collect copies of the data packets present at the visited network nodes. An agent visiting a node deposits there copies of all currently...

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  • Impact of SDN Controller’s Performance on Quality of Service

    Publikacja

    Software Defined Networking is a paradigm in network architecture; that is quickly becoming commonplace in modern telecommunication systems. It facilitates network customization for the requirements of different applications and simplifies the implementation of new services. Since its proposal, a significant evolution in its functionality has occurred. However, this development brought along problems of efficiency and performance,...

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