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Search results for: LAGRANGE'S ENERGY METHOD
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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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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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Low energy elastic scattering of electrons from hexafluoropropene (C3F6)
PublicationWe present cross sections from a joint experimental and theoretical study on elastic electron scattering from hexafluoropropene (C3F6) in the gas phase. The experimental results, using low energy electron spectroscopy, were obtained at incident electron energies of 0.5, 1, 1.5, 2, 3, 4, 5, 6, 10, 12, 15 and 20 eV, for scattering angles ranging from 10°to 130°. The theoretical method used in the computation of the integral, momentum...
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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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Numerical Analysis of Impact of Energy Buoy Anchoring Configurations on its Motion and Efficiency
PublicationThis paper presents a numerical analysis of the impact of energy buoy mooring configurations on its movement on the wave and effectiveness. The method used to analyse the buoy movement modelling in six degrees of freedom was described in a paper presented at the Conference 2011. Simulations of the buoy movement in regular wave and power calculations were conducted for several configurations of anchoring systems and position of...
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Advancing Solar Energy: Machine Learning Approaches for Predicting Photovoltaic Power Output
PublicationThis research is primarily concentrated on predicting the output of photovoitaic power, an essential field in the study of renewable energy. The paper comprehensively reviews various forecasting methodologies, transitioning from conventional physical and statistical methods to advanced machine learning (ML) techniques. A significant shift has been observed from traditional point forecasting to machine learning-based forecasting...
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Method of Skeletal System Modelling
PublicationAn original method of skeletal system modelling is presented in detail. Using DICOM images obtained from CT and PET tests, shell models of nine bones were created (humerus, radius, ulna, scapula, clavicle, femur, tibia, fibula, pelvis). Two methods of bone behaviour are also proposed, the first method treating the bone as a solid structure and the second method treating the bone as a complex porous structure. The behaviour of model...
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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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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...
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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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Low-energy interactions related to atmospheric and extreme conditions
PublicationThis Topical Issue, entitled “Low-Energy Interactions Related to Atmospheric and Extreme Conditions”, showcases a collection of eighteen articles that reported recent theoretical and experimental findings pertaining to the following topics: – low-energy interactions of charged particles (electrons [1–7], protons [8], positrons [9]), and photons [10] with atoms and molecules of biological [1–4,7,8], astrochemical [10], industrial,...
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Market value of PV battery systems for autonomous rural energy supply
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Comparison of physical performances of the ventilation systems in low-energy residential houses.
PublicationW artykule przedstawiono wyniki doświadczeń pomiaru efektywności różnych systemów wentylacyjnych w energooszczędnych budynkach mieszkalnych na terenie Niemiec. Porównano 4 różne systemy wentylacyjne. Dodatkowo wykonano ankiety wśród mieszkańców na temat opinii o systemach wentylacyjnych.
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Innovative system for energy collection and management integrated within a photovoltaic module
PublicationThe dynamic development of battery technology and design based on the flow of lithium ions, mainly driven by the needs of the automotive industry, leads to the conclusion that these batteries are becoming a more viable alternative to traditional lead-acid batteries. Their use is driven by the ability to quickly charge and discharge, a higher durability, maintenance-free operation, much smaller dimensions and lighter weight. The...
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Assessment of the Feasibility of Energy Transformation Processes in European Union Member States
PublicationThe energy transition is now treated in most countries as a necessary condition for their long-term development. The process of energy transformation assumes the simultaneous implementation of the Sustainable Development Goals, which are a major challenge for modern economies and introduce significant restrictions in their functioning. Our study aims to group EU member states according to their ability to achieve energy transition...
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Optimization of Train Energy Cooperation Using Scheduled Service Time Reserve
PublicationThe main aim of the paper was to develop an innovative approach to the preliminary estimation possibility of train energy cooperation based on data from timetables, without traction calculations. The article points out the need to strive for sustainable and environmentally friendly transport. It was pointed out that rail transport using electric traction is one of the more ecological branches of transport. It also offers a number...
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Nuclear power plant as a source of electrical energy and heat
PublicationIn this paper certain issues concerning usage of nuclear power plants as sources of not only electric power but also thermal energy will be discussed. For such a solution appeals most of all the need to limit harmful emissions of gases (including CO2) and ashes, which come from the process of burning fossil fuels, as well as the raising demand for network heat and chill. Additionally combined heat and power production brings measurable...
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Nonlinear Influence of Sound on the Vibrational Energy of Molecules in a Relaxing Gas
PublicationDynamics of a weakly nonlinear and weakly dispersive flow of a gas where molecular vibrational relaxation takes place is studied. Variations in the vibrational energy in the field of intense sound is considered. These variations are caused by a nonlinear transfer of the acoustic energy into energy of vibrational degrees of freedom in a relaxing gas. The final dynamic equation which describes this is instantaneous, it includes a...
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Storing thermal energy from solar collectors for the needs of a detached house
PublicationThis work evaluates the possibility of meeting a single familu household's need for hot water and heat year round, using solar collectors as the sole energy sourse. The main flaw of energetic systems based on solar energy is that the energy supply is usually insufficient in winter, when it is most needed. This work is going to show thatm for a house surface of 150 m2 and base dimension of 10x10m, it is possible to supply sufficient...
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Geometry optimization of steroid sulfatase inhibitors - the influence on the free binding energy with STS
PublicationIn the paper we review the application of two techniques (molecular mechanics and quantum mechanics) to study the influence of geometry optimization of the steroid sulfatase inhibitors on the values of descriptors coded their chemical structure and their free binding energy with the STS protein. We selected 22 STS-inhibitors and compared their structures optimized with MM+, PM7 and DFT B3LYP/6–31++G* approaches considering separately...
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Study of excitation energy transport and degradation in aqueous solution of FMN
PublicationStudy of excitation energy transport and degradation in aqueous solution of FMN
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Electron energy-loss spectroscopy of excited states of the diazine molecules: Pyridazine
PublicationExcitation of the valence electronic states of the pyridazine molecules in the gas phase have been studied using the technique of electron energy-loss spectroscopy. Varying the electron scattering conditions, the residual electron energy and scattering angle, enabled the optically-allowed and -forbidden excitations to be differentiated. The measured energy-loss spectra enabled the vertical excitation energies of the observed states...
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Optimisation of the Energy Consumption of a Small Passenger Ferry with Hybrid Propulsion
PublicationThe main goal in the design phase is to create a safe ship with a very efficient (and preferably zero-emission) propulsion system. To obtain such ships, new concepts are being developed for both propulsion systems and individual components. The choice of a propulsion system is not straightforward. To optimise the selection of the propulsion system, it is valuable to optimise the energy demand of this unit, which can be done by...
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AN ENERGY APPROACH TO THE FATIGUE LIFE OF SHIP PROPULSION SYSTEMS
PublicationThe conducted research investigations aimed to carry out an identification of the constructional materials fatigue state of the ship propulsions’ rotational mechanical units for diagnostic purposes. The fatigue cracks of the elements transmitting mechanical energy streams from the propulsion engines to the ship propellers or to the generators of the ship’s electric power station stand for a primary reason for the secondary, usually...
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Brief Announcement: Energy Constrained Depth First Search
PublicationDepth first search is a natural algorithmic technique for constructing a closed route that visits all vertices of a graph. The length of such route equals, in an edge-weighted tree, twice the total weight of all edges of the tree and this is asymptotically optimal over all exploration strategies. This paper considers a variant of such search strategies where the length of each route is bounded by a positive integer B (e.g. due...
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Hydrostatic drives as safe and energy saving machines. The drive investigation method compatible diagram of power increase opposite to the direction of power flow
PublicationProjektanci i producenci napędu hydrostatycznego nie dysponują możliwością dokładnego określania jego sprawności energetycznej zmieniającej się szeroko w polu pracy napędzanego urządzenia a więc w pełnym zakresie zmiany prędkości i obciążenia silnika hydraulicznego oraz lepkości zastosowanego czynnika roboczego. Dotyczy to zarówno określania strat i sprawności maszyn wyporowych (pompy i silnika hydraulicznego) zastosowanych w układzie...
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Smart heating system for home extending utilization of renewable energy sources
PublicationIn the paper a modern approach to smart home heating is presented. Proposed solution utilizes at least two low-polluting energy source technologies. The main idea is to connect well known ecological energy sources in a way that they can support each other and minimize risks of failure when using single system or even both of them but managed in separate way. Considered energy technologies, used separatelly, have disadvan-tages,...
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Energy losses reduction in the medium voltage cable line – case study
PublicationThe paper presents an analysis of energy losses in a power cable system, which is composed of two 30 kV cable lines. This cable system is located at the seaside holiday area, so the load profile during a year is specific. Energy losses related to reactive power transmission, as well as to currents induced in the sheaths of the cables, are subject to analysis. Measurements were made in the system in order to prepare a computer model...
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A novel degree-hour method for rational design loading
PublicationCooling degree-hours (CDH) received the broadest application in evaluation of the ambient air cooling efficiency in power engineering (engine intake air cooling systems) and air conditioning. The current CDH numbers are defined as a drop in air temperature multiplied by associated time duration of performance and their summarized annual number is used to estimate the annual effect achieved due to sucked air cooling in power plants...
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Smart and resilient cities- new challanges for Polish cities in terms of 2020 energy efficiency and climate action
PublicationGlobal climate change action along with energy efficiency optimizations are becoming increasingly pressing principles in terms of moving towards sustainable development. As a member of EU and UN Poland is also obliged to follow restricted rules concerning energy efficiency of buildings which come to force in 2020. To meet new goals, innovative approaches - like moving towards smart and resilient cities -may be required. Through...
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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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Transformation of Energy Markets: Description, Modeling of Functioning Mechanisms and Determining Development Trends
PublicationOne of the key contemporary economic and social issues today is the global energy transition. Energy transition processes are having a significant impact on the development of world economies, increasing their TFP and leading to an increase in their level of innovation through the transfer of myriad new technologies. These processes also contribute to an increase in foreign direct investment and, consequently, an increase in the...
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Energy Yield Generated by a Small Building Integrated Photovoltaic Installation
PublicationIn the recent years photovoltaic (PV) industry has experienced a major growth, caused by the ever present annual decrease in module production prices and the expanding awareness of the general public in terms of renewable energy. There are numerous ways to implement PV modules as an additional energy source for a building, be it mounted on the rooftop, or building integrated (BIPV). An analysis of BIPV consisting of 8 modules with...
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LEGAL ASPECTS OF ELECTRIC ENERGY GENERATION IN A FLOATING POWER PLANT
PublicationThis paper discusses the characteristics of pollution and legal regulations governing investment projects affecting the environment. It describes a combined system of a compression ignition engine and a steam turbine, whose aim, when placed on a floating platform, is to produce electric energy in a so-called distributed generation system. Such a system involves a reciprocating internal combustion engine and a connected steam turbine...
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Metamaterial-Based Sub-Microwave Electromagnetic Field Energy Harvesting System
PublicationThis paper presents the comprehensive analysis of the sub-microwave, radio frequency band resonant metastructures’ electromagnetic properties with a particular emphasis on the possibility of their application in energy harvesting systems. Selected structures based on representative topologies of metamaterials have been implemented in the simulation environment. The models have been analyzed and their substitute average electromagnetic...
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Similarities and differences in the production of renewable energy in Central and Eastern Europe countries
PublicationResearch background: In the era of climate change, environmental degradation, but also growing pub-lic awareness, there is a need to look for new ecological energy sources. This condition can be met by renewable energy sources (RES). The EU seeks to have a 32% share of its gross final energy consumption from renewable sources by 2030. While the EU as a whole is on course to meet its...
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An Enhanced Reduced Basis Method for Wideband Finite Element Method Simulations
PublicationIn this paper, we present a novel strategy for selecting expansion points in the reduced basis method. A single computation of the error estimator is used to select a few expansion points in the multi-parameter space simultaneously. The number of selected points is determined adaptively, based on the accuracy of the current reduced model. The reliability and efficiency of this proposed approach are illustrated by numerical tests...
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Low-energy positron collisions with water: elastic and rotationally inelastic scattering
PublicationDifferential, integral and momentum transfer cross sections for the vibrationally elastic and rotationally inelastic scattering of positrons from water at low collision energy (E ≤ 10 eV) are reported. Several models within the R-matrix method are used to compute the body-fixed T-matrices, while the scattering calculations are performed within the fixed-nuclei approximation corrected with the standard Born-closure formula. These...
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Analysis of an Energy Management System of a Small Plant Connected to the Rural Power System
PublicationThis paper presents the analysis of an energy management system (EMS) implemented to fulfill the requirements of a microgrid (MG) power supply owned by a small industrial company and connected to the rural power system. The main goal of this system is to ensure connection with the existing rural power system in terms of energy exchange, as well as to perform islanding mode operation of the microgrid based on the energy demand of...
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Deep learning-enabled integration of renewable energy sources through photovoltaics in buildings
PublicationInstalling photovoltaic (PV) systems in buildings is one of the most effective strategies for achieving sustainable energy goals and reducing carbon emissions. However, the requirement for efficient energy management, the fluctuating energy demands, and the intermittent nature of solar power are a few of the obstacles to the seamless integration of PV systems into buildings. These complexities surpass the capabilities of rule-based...
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Security of energy supply under the demonopolization of energy production in Poland,
PublicationOmówiono wzrost zapotrzebowania na energie elektryczną, udział nośników energii pierwotnej w pokryciu zapotrzebowania na paliwa. Omówiono pokrótce akty prawne związane z ochrona środowiska i energetyka. Scharakteryzowano proces starzenia się elektrowni w Polsce i rolę dużych elektrowni systemowych. Na tym tle przedstawiono rozproszone źródła energii elektrycznej i ich wpływ na bezpieczeństwo dostaw energii w sytuacjach ekstremalnych,...
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Multi-Option Model of Railway Traffic Organization Including the Energy Recuperation
PublicationThe article presents the issue of organization of railway traffic within the station, taking into account energy recuperation. We identified a number of factors which affect the energy efficiency of recuperation, including the issue of transfer of energy technology between a few vehicles. We presented some aspects of the decision problem of graphic train timetable construction with regard to recuperation. As an indicator of quality...
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Modern technologies in energy demand reducing of public transport — Practical applications
PublicationCity of Gdynia (Poland) exploits one of the most modern trolleybus network in Europe, which has been involved in many projects related to the reduction of energy consumption. Some of them are connected with the improving of energy breaking recovery usage. An experimental stationary storage system at Północna substation, which was tested in 2012-2014, is a bright example of a system which is connected with the improving of the...
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Energy and valuable organic products recovery from anaerobic processes
PublicationChapter 8 contains: Introduction, Energy balance in wastewater treatment plants and potential energy recovery, Potential valuable products recovery, Anaerobic processes focused on liquid products recovery; Anaerobic digestion (AD) processes focused on gaseous products recovery, Processes enhancing energy and valuable organic products recovery, Conclusions and perspectives. Anaerobic processes offer different pathways for the recovery...
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Experimental determination of H2 mass stopping powers for low-energy electrons
PublicationWe present experimental mass stopping powers of electrons in gaseous H2 obtained with an electron time- of-flight spectrometer, for the incident electron energy range of 11 to 25 eV. In our procedure, the average energy loss is derived from conversion of the measured electron time-of-flight spectra into equivalent electron energy-loss spectra. Our present results are compared with the only available experimental measurement and...
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Quasirelativistic potential energy curves and transition dipole moments of NaRb
PublicationWe report on extensive calculations of quasi-relativistic potential energy curves and, for the first time, transition dipole moments including spin-orbit and scalar-relativistic effects of the NaRb molecule. The calculated curves of the 0+, 0-, 1, 2 and 3 molecular states correlate for large internuclear separation with the fourteen lowest atomic energies up to the Na(3s ^2S_{1/2}) + Rb(7s ^2S_{1/2}) atomic limit. Several new features...
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Integrated algorithm for selecting the location and control of energy storage units to improve the voltage level in distribution grids
PublicationThis paper refers to the issue that mainly appears in distribution grids, where renewable energy sources (RES) are widely installed. In such grids, one of the main problems is the coordination of energy production time with demand time, especially if photovoltaic energy sources are present. To face this problem, battery energy storage units (ESU) can be installed. In recent years, more and more attention has been paid to optimizing...
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Grid-Forming Operation of Energy-Router Based on Model Predictive Control with Improved Dynamic Performance
PublicationThe focus of this study is on the grid-forming operation of the Energy Router (ER) based on Model Predictive Control (MPC). ER is regarded as a key component of microgrids. It is a converter that interfaces the microgrid (s) with the utility grid. The ER has a multiport structure and bidirectional energy flow control. The ER concept can be implemented in Nearly Zero-Energy Buildings (NZEB) to provide flexible energy control. A...
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Global energy transition: From the main determinants to economic challenges regions
PublicationDynamic global energy transition has been accelerating for the last decade. Interestingly, the energy transition is multidimensional and concerns both the dimensions of technique/ technology and the economic, social, institu-tional, and legal spheres (Shuguang et al., 2022; Tzeremes et al., 2022; Ram-zan et al., 2022; Tzeremes et al., 2022). The literature also points to the signif-icant impact of the digitization of the global...
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Potential energy curves, transition and permanent dipole moments of KRb
PublicationWe present extensive calculations of 48 adiabatic potential energy curves of the KRb molecule. Efforts have been focused on preparing the appropriate basis sets. Compared to previous approaches, the set of new potential energy curves is extended to higher excitations, including the single-excited K(4s2S)+Rb(5d2D) and double-excited K(4p2P)+Rb(5p2P) atomic limits. Larger distances between nuclei are also taken into account. New...