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Search results for: COHESIVE ENERGY DENSITY
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Influence of Bingham fluid viscosity on energy performances of a vortex chamber pump
PublicationOne of the problems in the development of coal-water technologies is the use of reliable and long-lasting pumps. To date, classic pumps, due to the use of mechanical moving parts and seals, are subject to rapid abrasive wear. The solution to this problem can lie in the creation of new vortex chamber pumps developed by the authors. They are highly reliable, simple in design and have no moving parts. The object of this paper consists...
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Low energy electron mass stopping power in H2
PublicationWe 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
PublicationSolar 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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Energy Consumption Modeling in SPMD and DAC Applications
PublicationIn 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...
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The Energy of Finance in Refining of Medical Surge Capacity
PublicationThe 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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A three-dimensional meso-scale approach with cohesive elements to concrete fracture based on X-ray μCT images.
PublicationArtykuł omawia wyniki numeryczne dotyczące pękania betonu uzyskane stosując trójwymiarowy model mezoskopowy z elementami kohezyjnymi. Obliczenia trójwymiarowe zostały wykonane dla zginanej belki betonowej. Beton został opisany jako model 3-fazowy. Mikrostruktura betonu odpowiadała zdjęciom tomograficznym. Wyniki numeryczne zostały porównane z wynikami doświadczalnymi. Uzyskano b. dobra zgodność między wynikami numerycznymi i doświadczalnymi.
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Alternative Energy: Photovoltaic Modules and Systems
PublicationUse 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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Energy Losses Due to Imperfect Payment Infrastructure and Payment Instruments
PublicationOne 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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Analysis of energy efficiency of suburban railway transport network
PublicationRising numbers of agglomeration residents cause increased need for people movement on daily basis. Because of congestion of local roads, air pollution and limited parking space, providing mass transit based on electric traction is reasonable. While the electric rail vehicles are considered highly efficient in themselves, they need to be analyzed as a part of a transport network, because energy consumption depends on operating conditions...
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THE MODELLING OF ACCUMULATION AND DISSIPATION OF ENERGY IN MECHANICAL DRIVE SYSTEM
PublicationThis 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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Microgrid Energy Management System
PublicationIn the era of rapid development of "green energy” and storage devices, microgrids implemented in line with the concept of distributed generation can be an effective form of power management. There is a need for an efficient, optimal and reliable control of the combined infrastructure. The article presents a flexible, configurable microgrid's resources control system, which executes the task of meeting the electricity demand of...
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Linear-scaling calculation of Hartree-Fock exchange energy with Non-orthogonal Generalised Wannier Functions
PublicationWe present a method for the calculation of four-centre two-electron repulsion integrals in terms of localised non-orthogonal generalised Wannier functions (NGWFs). Our method has been imple- mented in the ONETEP program and is used to compute the Hartree-Fock exchange energy component of Hartree-Fock and Density Functional Theory (DFT) calculations with hybrid exchange-correlation functionals. As the NGWFs are optimised in situ...
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On the use of a charge balancing method for low energy measurements
PublicationThe 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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Ground lemon and stevia leaves as renewable functional fillers with antioxidant activity for high-density polyethylene composites
PublicationThe development of new sustainable material solutions in the processing of thermoplastic polymers concerns both the application of biopolymers and the use of valorized plant derivatives as fillers and modifiers of petrochemical polymers. Herein, the possibility of using unprocessed raw parts of two commonly used in the food industry leaves, i.e., lemon (LL) and stevia (ST), as active and functional fillers for high-density polyethylene...
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Energy efficiency of electric multiple units in suburban operation
PublicationThis thesis presents approach to analysis of energy efficiency of a suburban rail network, using novel models developed on the Matlab/Simulink basis. Necessary features and requirements for such models were determined thru in-depth review of the source literature in all applicable fields: electrified transportation systems, electric multiple units construction, vehicle drivetrains and finally, existing simulation methods. Existing...
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HYBRID ENERGY SYSTEM FOR A CLASSIC SHIP POWER PLANT
PublicationThe 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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Potential Energy Curves of Diatomic Alkali Molecules Datasets
PublicationThe datasets described in this article contain potential energy curves for several diatomic systems. The data was obtained via high-performance computing using MOLPRO, a system of ab initio programs for advanced molecular electronic structure calculations. The datasets allow to model bond lengths, energy levels, spectra and time-evolution of molecular dimers for which the data are presented.
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Energy efficient beam control for 5G antennas
PublicationThe rapid development of 5G and beyond systems demands improvement in communication speed, latency and safety to maintain the required quality of service. This paper presents an overview of different concepts of energy-efficient antenna systems, which offer beam-shaping and beam-steering functionalities, that enhance connectivity performance and can be used in 5G applications. Different designs for 5.9 GHz, 39 GHz and 60 GHz frequency...
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Rational Use of Primary Energy in Single-Family Residential Houses
PublicationThis 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
PublicationThis 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
PublicationSolar 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
PublicationThe 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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Price Changes in Wholesale Market of Electrical Energy in Poland
PublicationThe 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
PublicationEvery 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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Structure and elastic properties of Mg(OH)2from density functional theory
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Energetic density of states in copper phthalocyanine studied by modulated photocurrent method
PublicationPrzy pomocy metody modulowanych fotoprądów określono różniczkowy i całkowy rozkład stanów pułapkowych w naparowanej ftalocyjaninie miedzi w koplanarnej konfiguracji elektrod próbki.
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Influence of initial density of cohesionless soil on evolution of passive earth pressure
PublicationArtykuł porusza problem odporu bezkohezyjnego gruntu. Obliczenia wykonano wykorzystując metodę elementów skończonych na bazie mikropolarnego prawa hipolastycznego. W obliczeniach przyjęto różne początkowe zagęszczenia oraz średnice cząstek gruntu.
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Collective modes of the extended Hubbard model with negativeUand arbitrary electron density
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Direct estimation of functional and density operators by local operations and classical communication.
PublicationWykazano, że można dokonywać detekcji splątania w paradygmacie odległych laboratoriów. Pokazano, jak można fizycznie zaimplementować strukturalne przybliżenie fizyczne niefizycznego odwzorowania w tym paradygmacie.
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Computer -Aided Local Energy Planning Using ALEP-PL Software
PublicationThe issue of energy system planning, including the planning of local energy systems, is critical, since it affects the security of energy supplies in communities, regions, and consequently the security of energy supply within the country. Energy planning is a complex process that requires integration of different goals i.e. improvement of energy efficiency, increase in the share of renewables in the energy balance and CO2} emission...
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Collaborative Exploration of Trees by Energy-Constrained Mobile Robots
PublicationWe study the problem of exploration of a tree by mobile agents (robots) that have limited energy. The energy constraint bounds the number of edges that can be traversed by a single agent. We use a team of agents to collectively explore the tree and the objective is to minimize the size of this team. The agents start at a single node, the designated root of the tree and the height of the tree is assumed to be less than the energy...
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HISTORY OF INITIAL ENERGY AND WATER NETWORK DEVELOPMENT IN QATAR
PublicationQatar: A country which had to be associated with neighboring countries like UAE or Saudi Arabia for people to know about it, stands proud today due to the ample production and exporting of Black Gold. A country with almost no vegetation or suitable weather to harvest crops, turned from being heavily dependent on trading Pearls to exporting natural oil and gas to all over the globe. The paper outlines in details the history of the...
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Cascading transitions toward unconventional charge density wave states in the quasi-two-dimensional monophosphate tungsten bronze P4W16O56
PublicationSingle crystals of the m = 8 member of the low-dimensional monophosphate tungsten bronzes (PO2)4(WO3)2m family were grown by chemical vapour transport technique and the high crystalline quality obtained allowed a reinvestigation of the physical and structural properties. Resistivity measurements revealed three anomalies at TC1 = 258 K, TC2 = 245 K and TC3 = 140 K, never observed until now. Parallel X-ray diffraction investigations...
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Fine-Tuning the Photocatalytic Activity of the Anatase {1 0 1} Facet through Dopant-Controlled Reduction of the Spontaneously Present Donor State Density
PublicationThe present study highlights the importance of the net density of charge carriers at the ground state on photocatalytic activity of the faceted particles, which can be seen as a highly underexplored problem. To investigate it in detail, we have systematically doped {1 0 1} enclosed anatase nanoparticles with Gd3+ ions to manipulate the charge carrier concentration. Furthermore, control experiments using an analogical Nb5+ doped...
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Collaborative Delivery by Energy-Sharing Low-Power Mobile Robots
PublicationWe study two variants of delivery problems for mobile robots sharing energy. Each mobile robot can store at any given moment at most two units of energy, and whenever two robots are at the same location, they can transfer energy between each other, respecting the maximum capacity. The robots operate in a simple graph and initially each robot has two units of energy. A single edge traversal by an robot reduces its energy by one...
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Energy Transition in Poland—Assessment of the Renewable Energy Sector
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Applying Web 2.0 Concepts to Creating Energy Planning Portal
PublicationCommunity authorities in Europe are tasked to create Advanced Local Energy Plans (ALEP), which encompasses collecting local data on current energy use and generation, as well as generating future development scenarios. Both the data and the development scenarios must be publicly accessible as a basis for energy-related decisions taken by residents, local companies and other local institutions. The data must partially be collected...
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A study of the electronic states of pyrimidine by electron energy loss spectroscopy
PublicationThe electron energy loss spectra were measured in pyrimidine at the constant electron residual energy varied from 15 meV to 10 eV and in the scattering angle range 0–180°. The spectra were analysed applying an iteration fitting procedure to resolve the energy loss bands corresponding to excitation of the electronic states of pyrimidine. The vertical excitation energies of the singlet states of pyrimidine and of a number of the...
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EE-ISAC—Practical Cybersecurity Solution for the Energy Sector
PublicationA recent survey of cybersecurity assessment methods proposed by the scientific community revealed that their practical adoption constitutes a great challenge. Further research that aimed at identifying the reasons for that situation demonstrated that several factors influence the applicability, including the documentation level of detail, the availability of supporting tools, and the continuity of support. This paper presents the...
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Electron energy-loss spectroscopy of excited states of the pyridine molecules
PublicationElectron energy-loss spectra of the pyridine, C5H5N, molecules in the gas phase have been measured to investigate electronic excitation in the energy range 3.5–10 eV. The applied wide range of residual electron energy and the scattering angle range from 10 ◦ to 180 ◦ enabled to differentiate between optically-allowed and -forbidden transitions. These measurements have allowed vertical excitation energies of the triplet excited...
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AC-DC-DC Converter for Small Power Energy Storage Systems
PublicationThe energy transformation driven by the development of renewable energy sources has become a reality for all power grid users. Prosumer energy, primarily utilizing photovoltaic installations, is one of the fastest-growing market segments. The advancement of technology, a decrease in electrochemical energy storage prices, and changes in the legal framework governing energy billing for grid-fed power have led to a growing interest...
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TEST FOR ASSESSING THE ENERGY EFFICIENCY OF VEHICLES WITH INTERNAL COMBUSTION ENGINES
PublicationThe most popular method for assessing the energy efficiency of vehicles is to compare the fuel consumption achieved in the conditions of selected approval test. Operating conditions are defined using the speed profiles, usually for only two categories: urban and extra-urban driving. Assessing the energy efficiency of vehicles should be performed using a more detailed classification of conditions. Presented results of comparison...
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High-efficient, zero-emission energy production
PublicationThis paper presents innovative thermodynamiccycles with high-efficient, zero-emission energy production. The main aim of this work is to show the role of nano-phenomena in the enhancement of the power of thermodynamic cycles. For that purpose, the cycles using oxy-combustion and spray ejected condensation are first studied and, secondly hybrid cycles using fuel cells and gas turbines are presented. The role of nano-phenomena in...
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Managerial Energy in Sustainable Enterprises: Organizational Wisdom Approach
PublicationThe circular economy (CE) as an idea involves applying the concept of sustainable development that has been gaining worldwide support. This shift in perception of energy and resource-use from its linear to circular forms creates a specific business environment, which constitutes the subject of this research. This article aims to analyze the impact of a manager’s energy on organizational wisdom, focusing on its circular business...
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Estimation of Vehicle Energy Consumption at Intersections Using Microscopic Traffic Models
PublicationThis paper addresses issues related to modeling energy consumption and emissions using microscopic traffic simulations. This paper develops a method in which a traffic model is used to calculate the energy needed to travel through selected types of intersections. This paper focuses on energy consumption and derived values of calculated energy, which can be, for example, carbon dioxide emissions. The authors present a review of...
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Influence of Installation Effects on Pile Bearing Capacity in Cohesive Soils – Large Deformation Analysis Via Finite Element Method
PublicationIn this paper, the whole process of pile construction and performance during loading is modelled via large deformation finite element methods such as Coupled Eulerian Lagrangian (CEL) and Updated Lagrangian (UL). Numerical study consists of installation process, consolidation phase and following pile static load test (SLT). The Poznań site is chosen as the reference location for the numerical analysis, where series of pile SLTs...
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Energy-Aware Scheduling for High-Performance Computing Systems: A Survey
PublicationHigh-performance computing (HPC), according to its name, is traditionally oriented toward performance, especially the execution time and scalability of the computations. However, due to the high cost and environmental issues, energy consumption has already become a very important factor that needs to be considered. The paper presents a survey of energy-aware scheduling methods used in a modern HPC environment, starting with the...
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Energy Efficiency and Economic Policy: Comprehensive Theoretical, Empirical, and Policy Review
PublicationIn this paper, we analyze the role of economic policy in prompting energy efficiency. This study reviews three aspects, theoretical, empirical, and existing policies to evaluate the relationship of energy efficiency and economic policy. This study furthermore identifies the existing issues from a policy perspective in energy efficiency. Although not all public policies may be justified, it suggests that these types of financial...
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Modeling energy consumption of parallel applications
PublicationThe paper presents modeling and simulation of energy consumption of two types of parallel applications: geometric Single Program Multiple Data (SPMD) and divide-and-conquer (DAC). Simulation is performed in a new MERPSYS environment. Model of an application uses the Java language with extension representing message exchange between processes working in parallel. Simulation is performed by running threads representing distinct process...
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Energy consumption estimation of low-power devices using an integrating coulombmeter
PublicationThe main problem in designing devices powered with Energy Harvesting is an estimation of energy demand of low-power devices as well as quantity of energy provided by the selected energy transducer in the assumed work conditions. Due to the work characteristic of each block of the device and properties of the measured signal, measurement is not trivial. The paper presents the proposal of the micro-charge measurement device based...