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Search results for: THERMODYNAMIC CYCLE CONCEPTS
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Analysis of the selection of low-temperature medium for a turbine power plant using ocean thermal energy (OTEC)
PublicationThe paper presents the results and conclusions of numerical calculations modelled in the EES program of a closed OTEC cycle. The following mediums were analysed: ammonia, R32, R41, R404a, R407c, R410a, R423a, R500, R502, R507a and R114, R152a, R234fa, R600, R1234yf, R1234ze. Analogous assumptions were adopted as in the ORC cycle with heat regeneration for dry refrigerants without regeneration for wet refrigerants. Each of them...
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Analysis of the selection of low temperature medium for a turbine power plant using ocean thermal energy (OTEC)
PublicationThe paper presents the results and conclusions of numerical calculations modelled in the EES program of a closed OTEC cycle. The following mediums were analysed: ammonia, R32, R41, R404a, R407c, R410a, R423a, R500, R502, R507a and R114, R152a, R234fa, R600, R1234yf, R1234ze. Analogous assumptions were adopted as in the ORC cycle with heat regeneration for dry refrigerants without regeneration for wet refrigerants. Each of them...
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Low frequency nois of supecapacitor
Open Research DataDataset contains noise measurement results on prototype electrochemical double layer capacitor. The measurement procedure is described in https://dx.doi.org/10.1515/mms-2017-0059.
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Depth profile of the gold-silver bimetallic structures
Open Research DataSilver and gold bimetallic layers were deposited on a silicon substrate by magnetron sputtering method. Both, Au and Ag layers had 3 nm of thickness. That prepared nanostructures were measured by XPS method. To obtain a depth profile of chemical composition, an Argon ion (Ar+) gun was used for etching surface of sample. Each cycle of etching takes 30...
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Motives for Going International and Entry Modes of Family Firms in Poland
PublicationThe artucule in the theoretical part focuses on theoretical concepts of firm internationalisation and specifics of internationalisation of FBs, especially their motives for going international. In the empirical part the quqantitative approach is adopted. The results of survey are presented on the sample of 216 firms, including 88 FBs. The statistical analysis is carried out
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Dis/Trust and data-driven technologies
PublicationThis concept paper contextualises, defines, and systematises the concepts of trust and distrust (and their interrelations), providing a critical review of existing literature so as to identify gaps, disjuncture, and continuities in the use of these concepts across the social sciences and in the context of the consolidation of the digital society. Firstly, the development of the concept of trust is explored by looking at its use...
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Molywood: streamlining the design and rendering of molecular movies
PublicationMotivation High-quality dynamic visuals are needed at all levels of science communication, from the conference hall to the classroom. As scientific journals embrace new article formats, many key concepts – particularly in structural biology – are also more easily conveyed as videos than still frames. Notwithstanding, the design and rendering of a complex molecular movie remain an arduous task. Here, we introduce Molywood, a robust...
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Selected aspects of performance of organic Rankine cycles incorporated into bioenergy with carbon capture and storage using gasification of sewage sludge
PublicationThe study aims to investigate the application of the Organic Rankine Cycle (ORC) in the bioenergy with carbon capture and storage (BECCS) using gasification of sewage sludge. The tool used in the investigation is the Aspen Plus software with REFPROP property methods for calculating fluid properties. The reason for this study is that a detailed analysis of the proposed BECCS process flow diagram indicates that a certain amount of...
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The Influence of Sulfate on Anaerobic Ammonium Oxidation in a Sequencing Batch Reactor
PublicationAnaerobic ammonia-oxidizing bacteria have a more comprehensive metabolism than expected - there may be other electron acceptors that oxidize ammonium nitrogen under anaerobic conditions, in addition to the well-known nitrite nitrogen, one of which is sulfate in the sulfammox process. Sulfate-containing compounds are part of the medium for the anammox process, but their concentrations are not particularly high (0.2 g MgSO4 ∙ 7H2O/dm3...
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Unlocking creativity with new technologies
PublicationArtificial intelligence, augmented and virtual reality, Internet of Things and digital twins are just a few concepts related to the fourth industrial revolution that is happening right before our eyes. The key question asked by managers in the aerosol sector recently is: what does all this new technology mean to me?
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Theory of Urban Design 2023/24 - LECTURES
e-Learning CoursesIntroductory lectures on the topic of urban design concepts in contemporary climate change, sustainable development and the creation of public spaces.
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Anna Rzeczycka dr hab.
PeopleAnna Rzeczycka is the deputy head of the Department of Finance at the Faculty of Economics and Management of the Gdańsk University of Technology. Publications are situated in the field of social sciences in the discipline of economics and finance. They include books, monographs, articles, publications and scientific editions of monographs and scientific journals. In terms of numbers, it includes the following items: 12 monographs...
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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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Thermal self-action effects for acoustic beams containing fronts in a Maxwell relaxing fluid
PublicationThis paper examines the thermal self-action of acoustic beams in a Maxwell relaxing fluid. This type of thermal self-action differs from that in a Newtonian fluid and behaves differently depending on a ratio of sound period and time of thermodynamic relaxation. The self-action which relates to sound beams containing shock fronts is also discussed. In addition, stationary and non-stationary types of self-action are considered.
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Problem of aggregation in dye-DNA interaction, calorimetry studies
PublicationNucleic acids are the biological target for many antimicrobial, antitumor and antiviral drugs. Ligand-DNA interactions can be classified into two major categories: 1. covalent binding, which can provide to intermolecular adducts, 2. physico-chemical interactions, which can be divided into intercalation (e.g. adriamycin) or groove binding (e.g. dystamycin). There are several methods to investigate interactions between drug and DNA....
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Konzetrationslöschung durch Energieübertragung bei der Lumineszenz von Lösungen
PublicationThe absorption spectra and quantum yields of the fluorescence of rhodamine 6 G are investigated in two different water-glycerol mixtures as a function of the rhodamine concentration. The observed concentration quenching is attributed to the formation of rhodamine dimers and the decrease in quantum yield is compared with theoretical concepts about concentration quenching by energy transfer to the dimers.
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Music Information Retrieval in Music Repositories
PublicationThis chapter reviews the key concepts associated with automated Music Information Retrieval (MIR). First, current research trends and system solutions in terms of music retrieval and music recommendation are discussed. Next, experiments performed on a constructed music database are presented. A proposal for music retrieval and annotation aided by gaze tracking is also discussed.
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Thermal failure of a second rotor stage in heavy duty gas turbine
PublicationThe impulse mode of operation and the supply of various types of fuels causes frequent failures even in the heavy duty gas turbines. The paper presents the ravages of second rotor stage failure in a gas turbine. The excessive thermal elongation rise caused by fuel change was indicated as the main cause. We applied nonlinear numerical analysis, preceded by thermodynamic calculations of the turbine and visual inspection of the effects...
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Cycling performances of the V2O5 nanorods as cathode material in Li-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanorods obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 and 2C current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here 1C is 294 mAh g-1. The...
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Cycling performances of the V2O5 nanocrystals as cathode material in Li-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanocrystals obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 and 2C current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here 1C is 294 mAh g-1. ...
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Depth profile of the chemical composition of the Au-Ag multilayers
Open Research DataSilver and gold multilayers were deposited on a silicon substrate by magnetron sputtering method. Both type, Au and Ag thin films had 2 nm of thickness. Totally structure had thickness of 6 nm (Au-Ag-Au). That prepared multilayers were measured by XPS method. To obtain a depth profile of chemical composition, an Argon ion (Ar+) gun was used for etching...
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HEALTH-AFFIRMING EVERYDAY LANDSCAPES IN SUSTAINABLE CITY. ECO-NEIGHBORHOODS IN FRANCE CASE
PublicationThis paper discusses the close relationship between the concept of health-affirming everyday landscapesand the idea of sustainable city design.The French National program of eco-neighborhood certification ÉcoQuartier is described and the correlation between the concepts of health-affirming landscapes,sustainable cities, and eco-neighborhoods is explained using the example of a selected eco-neighborhood in France.
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Derivation of motor mean phase currents in PMSM drives operating with low switching-to-fundamental frequency ratio
PublicationPulse width modulation (PWM) of inverter output voltage causes the waveforms of motor phase cur-rents to consist of distinctive ripples. In order to provide suitable feedback for the motor current con-trollers, the mean value must be extracted from the currents’ waveforms in every PWM cycle. A com-mon solution to derive the mean phase currents is to sample their value at the midpoint of a symmetrical PWM cycle. Using an assumption...
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NUMERYCZNY MODEL OBLICZENIOWY OBIEGU TURBINY KLASY 300 MW
PublicationNiniejszy artykuł stanowi opis modelu obiegu cieplnego turbiny o mocy 360MW, utworzonego w preprocesorze numerycznego programu obliczeniowego onazwie DIAGAR. Zadaniem opisywanego modelu jest odtwarzanie zjawisk fizycznych zachodzących w poszczególnych urządzeniach składowych obiegu, zarówno podczas poprawnej (sprawnej) pracy bloku energetycznego, jak i w przypadku pojawienia się niesprawności. Utworzony...
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Ocena kosztu cyklu życia szyn kolejowych w modernizacji układów geometrycznych
PublicationW pracy przedstawiono uwarunkowania historyczne, które doprowadziły do opracowania metod szacowania kosztu życia inwestycji. Opisano podstawowe założenia LCC według modelu przedstawionego w Normach oraz opracowanego w projekcie INNOTRACK. Zaproponowano połączenie powyższych metod i dostosowanie ich do oceny kosztu życia szyn kolejowych w Polce. Przedstawiono elementy wpływające na koszt utrzymania nawierzchni szynowej oraz metody...
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Smart Specializations as Innovative Ecosystems
PublicationIn the article it is showed that regional smart specializations that are currently the most important tool of the European innovation policy may be perceived, and if effective should constitute, innovative ecosystems. The article presents the concepts of smart specializations and innovative ecosystems. The concept of innovative ecosystem is, in the article, presented from the perspective of its foundation and relations to other...
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From fluid mechanics backgrounds to modern field theory
PublicationOur presentation keeps a historical line of reasoning, since we start from old concepts of fluid mechanics and finish on concepts of modern field theory. We want to show that some facts from the nature phenomena, which have firstly been discovered on the ground of fluid mechanics, were next incorporated into physics and later become the important pattern for whole mathematical physics. Especially, well-known continuum models, which...
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Mathematical models of process quality on the example of the bakery industry
PublicationThis article presents a new approach to quantitative dimensionless assessment of the efficiency and competitiveness of production processes. New concepts of process quality and relative product quality have been introduced. Process quality was expressed in vector and scalar. The process quality vector ono was expressed by the product of reliability by the vector from the sum of three components taking into account the composition...
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Cycling performances of the V2O5 nanostructures as cathode material in Na-ion batteries
Open Research DataThe DataSet contains the next one hundred galvanostatic charge/discharge curves of the V2O5 nanostructures with different morphology obtained by the sol-gel method. The battery tests of the samples were performed using the Atlas-Sollich 0961 (Atlas-Sollich, Poland) with C/5 current densities in the voltage range between 2.0 V and 4.0 V vs. Li/Li+. Here...
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ALLYING SYSTEM THINKING AND SET OF EXPERIENCE KNOWLEDGE STRUCTURE
PublicationThe approach of system thinking is completely different from traditional forms of analysis. Even the ancient meaning of word analysis is “a breaking up”. Set of Experience Knowledge Structure is an atomic record of decision event that can be grouped together and form some form of decision DNA of an organization. The question that this paper is trying to answer in how those concepts can be merged.
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Combined cold supply system for ship application based on low GWP refrigerants - Thermo-economic and ecological analyses
PublicationThe withdrawal of popular high-GWP refrigerants will significantly affect maritime industry. Refrigeration and air conditioning systems currently used on ships are not ready to fulfil future limitations. Therefore, there is a need for system, which will operate with low-GWP refrigerants and at the same time will be efficient and reliable in difficult environmental conditions. This paper explains the concept of a cold supply system,...
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Feasibility of combined diesel engine - steam turbine in power station operating in the maritime
PublicationCompression-ignition engines used in ship technology as main propulsion engines are large units reaching even to 50-60 MW. Currently, the efficiency of such engines amounts to 45-50%. With such a large power unit, exhaust gases leaving the engine contain very large quantities of heat available for further treatment. Exhaust gases from the piston engine contain about 25% of the heat supplied to the engine in the fuel. Using the...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...
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Design analysis of combined gas-vapour micro power plant with 30 kW air turbine
PublicationThe article presents basic results of the design analysis of a combined gas-vapour micro power plant with a waste-heat boiler without exhaust reheat, working in the vapour section in the Organic Rankine Cycle (ORC) system. The analysis concerned working media most frequently used in those types of power plants and planned to be used in future. The object of the analysis was a micro power plant with a 30 kW gas (air) turbine for...
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Exergy analysis of a negative CO2 emission gas power plant based on water oxy-combustion of syngas from sewage sludge gasification and CCS
PublicationA power cycle with water-injected oxy-combustion (water cycle) is investigated by exergy analysis. It is fueled with syngas (aka. producer gas) from gasification of sewage sludge. The cycle is equipped with a spray-ejector condenser (SEC). CO2 is separated and compressed for transportation and storage. The net delivered electric power is 31% of the fuel exergy. The task efficiency is 39% when the flue gas bleed to gasification...
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Hysteresis curves for some periodic and aperiodic perturbations in gases
PublicationEvolution of sound in a medium whose properties irreversibly vary in the course of wave propagation, is studied. For example, a gas that is a particular case of a Newtonian fluid is considered. Hysteresis curves, pictorial representations of irreversible attenuation of the sound energy, in the plane of thermodynamic states are plotted. The irreversible losses in internal energy are proportional to the total attenuation and depend...
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Framework for RIDM within functional safety management process
PublicationThe functional safety management in life cycle is a complex process starting with identifying hazards and defining safety-related functions (SRFs) with risk assessment oriented at determining the safety integrity level. Another element of such life cycle is a verification of required SIL for designed safety-related system which implements safety function. Due to complexity of the problem, to overcome difficulties in safety-related...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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Analysing selection of low-temperature medium for cogeneration micro power plant
PublicationThe article analyses the ORC system working with dry and wet low-boiling media which are most frequently used in installations of this type. Two types of cycles were examined, which were the cycle with heat regeneration for dry media: fc72, hfe7100, R227ea, R245fa, R423a and R600a, and the cycle without heat regeneration for wet media: R11, R12, R134a, R718 and 507a. The calculations were performed for the assumed required thermal...
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Model obliczania kosztu cyklu życia obiektu na przykładzie budynku mieszkalnego jednorodzinnego
PublicationW artykule przedstawiono model obliczania kosztu cyklu życia budynku mieszkalnego jednorodzinnego oraz wskazano możliwości ograniczenia wydatków związanych z jego użytkowaniem w okresie trzydziestu lat. Celem prezentowanej analizy rachunku kosztu cyklu życia jest porównanie i ocena kosztów nabycia i użytkowania domu realizowanego według alternatywnych technologii z uwzględnieniem przyjętych rozwiązań w zakresie pozyskania energii,...
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Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant
PublicationOne promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle...
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Dual polarization antennas for UHF RFID readers
PublicationThis paper presents various concepts of switching polarization in patch antenna dedicated for UHF RFID readers. Proposed designs allow for switching between linear and circular polarization. The first design does not require electronic switching as the polarization can be changed by choosing one of two available feeding terminals. Two remaining designs use PIN diode or FET SPDT switch.
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Experience Visualizaton
PublicationSet of Experience Knowledge Structure (SOEKS) has proved its capability of storing substantial part of experience at a particular decision point. The management of SOEKS record is also proposed in many papers for example referring to concepts of Decisional DNA knowledge representation, that is a collection of a number of SOEKS. The aim of this paper is to focus on visualization and practical aspects of presenting gathered knowledge...
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Singular curves in the resultant thermomechanics of shells
PublicationSome geometric and kinematic relations associated with the curve moving on the shell base surface are discussed. The extended surface transport relation and the extended surface divergence theorems are proposed for the piecewise smooth tensor fields acting on the regular and piecewise regular surfaces. The recently formulated resultant, two-dimensionally exact, thermodynamic shell relations - the balances of mass, linear and angular...
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Skutki zwarć łukowych w średnionapięciowych rozdzielnicach okrętowych z izolacją powietrzną
PublicationW artykule scharakteryzowano moc i napięcie łuku, jak również przedstawiono model termodynamiczny służący do obliczania ciśnienia i temperatury gazów w otoczeniu łuku zwarciowego. Przedstawiono przykładowy układ elektrowni okrętowej i zasilania najważniejszych odbiorników na statku do przewozu kontenerów, w tym 600 kontenerów chłodzonych. Na podstawie parametrów prądnic i silników, odbiorników zasilanych z rozdzielnicy głównej...
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Karol Grębowski dr inż.
PeopleKarol Grębowski (M.Sc.) works as an assistant at the Department of Technical Fundamentals of Architecture Design of the Faculty of Architecture at Gdansk University of Technology. His scientific research deals with dynamic phenomena occurring during the vibration of structures, bridges, and studies the design methodology of the elements forming passive protection system of the vehicles degraded by struck or explosion in the context...
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Water-Lubricated Journal Bearings Marine Applications, Design, and Operational Problems and Solutions
PublicationWater-Lubricated Journal Bearings: Marine Applications, Design, and Operational Problems and Solutions provides cutting-edge design solutions, common problems and methods for avoiding them, and material selection considerations for the use of water-lubricated journal bearings in marine environments. These bearings have many advantages, including the absence of the potential for oil contamination. They are also sensitive, and their...
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KOMPOZYTOWY MOST PIESZO - ROWEROWY
PublicationPaper presents the composite foot and cycle bridge developed in FOBRIDGE grant cofinanced by The National Centre for Research and Development and realized by consortium of Gdansk University of Technology (leader), Military University of Technology in Warsaw and ROMA Sp. z o.o. in Toruń. The purpose of the grant was to design a shell type single span foot and cycle bridge made of composite materials, with the assumption of manufacturing...
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The Dilemmas of Choosing a Suitable Technology for Low Energy and Passive Houses in the Context of their Overheating Issues
PublicationIn compliance with European Union directives, numerous countries are introducing increasingly stricter legal limits on the estimated energy consumption of newly designed residential buildings. However, the fact, that regulations and designers' efforts are focused on decreasing energy consumption (and consequently carbon dioxide emissions) only at the post-occupancy stage, may lead to a significant increase in the carbon footprint...
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Induction of the common-sense hierarchies in lexical data
PublicationUnsupervised organization of a set of lexical concepts that captures common-sense knowledge inducting meaningful partitioning of data is described. Projection of data on principal components allow for dentification of clusters with wide margins, and the procedure is recursively repeated within each cluster. Application of this idea to a simple dataset describing animals created hierarchical partitioning with each clusters related...