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Wyniki wyszukiwania dla: COMPASS

  • The Backbone Coloring Problem for Small Graphs

    In this paper we investigate the values of the backbone chromatic number, derived from a mathematical model for the problem of minimization of bandwidth in radio networks, for small connected graphs and connected backbones (up to 7 vertices). We study the relationship of this parameter with the structure of the graph and compare the results with the solutions obtained using the classical graph coloring algorithms (LF, IS), modified...

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  • Polyethylene glycol-coated solid-phase microextraction fibres for the extraction of polar analytes-A review

    The article discusses the merits and limitations of commercially available solid-phase microextraction (SPME) fibres and compares them with the new type of extraction coatings, in particular those containing polyethylene glycol as sorbent, as well as the methods of the preparation of the latter. It also analyses their possible application for the extraction of a broad spectrum of analytes, with particular emphasis on the sampling...

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  • Using GPUs for Parallel Stencil Computations in Relativistic Hydrodynamic Simulation

    Publikacja
    • S. Cygert
    • D. Kikoła
    • J. Porter-Sobieraj
    • J. Sikorski
    • M. Słodkowski

    - Rok 2014

    This paper explores the possibilities of using a GPU for complex 3D finite difference computation. We propose a new approach to this topic using surface memory and compare it with 3D stencil computations carried out via shared memory, which is currently considered to be the best approach. The case study was performed for the extensive computation of collisions between heavy nuclei in terms of relativistic hydrodynamics.

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  • Workbook for cooperative development of personnell and organisation for innovation in SME in the Baltic Sea Region

    Publikacja

    - Rok 2012

    This study highlights the potential for cooperative development of personnel and organisational innovations in SMEs and gives an example implemented by the University of Lund together with the Municipality of Astorp and local companies. This innovation field is of particular importance for all companies in the region, since it does apply to any professional sector, be it a service oriented company or a manufacturing business. This...

  • Personal Branding—A New Competency in the Era of the Network Economy. Corporate Brand Performance Implications

    Publikacja

    - Rok 2018

    Primary assets of the network economy are information, network, re-lationships, knowledge, and a virtual environment. The competency of personal branding exercised by knowledge workers, also thought of as knowledge producers, is becoming a natural consequence of the business environment where the significance of hierarchies is constantly decreasing. Knowledge workers are powerful as never be-fore and can exist as separate actors...

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  • Path-based methods on categorical structures for conceptual representation of wikipedia articles

    Machine learning algorithms applied to text categorization mostly employ the Bag of Words (BoW) representation to describe the content of the documents. This method has been successfully used in many applications, but it is known to have several limitations. One way of improving text representation is usage of Wikipedia as the lexical knowledge base – an approach that has already shown promising results in many research studies....

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  • CORPORATE BANKRUPTCY PREDICTION IN POLAND AGAINST THE BACKGROUND OF FOREIGN EXPERIENCE

    Publikacja

    In highly developed countries, research in the field of bankruptcy risk prediction has been conducted for many years. For example, in the United States, which can be considered a pioneering country, the first publications appeared in the early twentieth century. In Poland, due to political and economic reasons, the interest in this issue dates back to the early 1990s. For this reason, this publication attempts to answer the following...

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  • CORPORATE BANKRUPTCY PREDICTION IN POLAND AGAINST THE BACKGROUND OF FOREIGN EXPERIENCE

    Publikacja

    In highly developed countries, research in the field of bankruptcy risk prediction has been conducted for many years. For example, in the United States, which can be considered a pioneering country, the first publications appeared in the early twentieth century. In Poland, due to political and economic reasons, the interest in this issue dates back to the early 1990s. For this reason, this publication attempts to answer the following...

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  • Novel doubly perforated broadband microstrip branch-line couplers

    Two broadband compact doubly perforated hybrid couplers have been designed, manufactured, and measured. To improve frequency characteristics and to reduce circuit dimensions, two kinds of perforations have been introduced: the defected ground structures in the ground plane metallization and photonic bandgap cells in the strip metallization. Measurement results show essential miniaturization (~39% and ~36%) and enhancement of the...

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  • Fast Antenna Optimization Using Gradient Monitoring and Variable-Fidelity EM Models

    Accelerated simulation-driven design optimization of antenna structures is proposed. Variable-fidelity electromagnetic (EM) analysis is used as well as the trust-region framework with limited sensitivity updates. The latter are controlled by monitoring the changes of the antenna response gradients. Our methodology is verified using three compact wideband antennas. Comprehensive benchmarking demonstrates its superiority over both...

  • Broadside coupled stripline with double-side UC-PBG structure

    Publikacja

    Rozważono strukturę linii paskowych sprzężonych szerokim bokiem z periodycznie zaburzoną metalizacją masy typu UC-PBG (Uniplanar Compact - Photonic BandGap). W celu oceny przydatności struktury zaprojektowano, wykonano i przebadano sprzęgacz 3dB. Potwierdzono przewidywany efekt spowolnienia fali (slow wave effect), którego konsekwencją jest możliwość znacznej redukcji wymiarów układu.

  • Research on protection mechanisms of Resilient Packet Ring Network.

    Publikacja

    Paper describes iSteering - a new method to control traffic in case of RPR network failure. There's comparison of packet wrapping, steering and our proposed method iSteering, which can be used in case of transmitter/receiver or fiber failure. Numerical analysis for even and random traffic flow has been made in order to compare packet wrapping, steering and iSteering. The results of all the tests are included.

  • Study of the Effectiveness of Model Order Reduction Algorithms in the Finite Element Method Analysis of Multi-port Microwave Structures

    Publikacja

    - Rok 2022

    The purpose of this paper is to investigate the effectiveness of model order reduction algorithms in finite element method analysis of multi-port microwave structures. Consideration is given to state of the art algorithms, i.e. compact reduced-basis method (CRBM), second-order Arnoldi method for passive-order reduction (SAPOR), reduced-basis methods (RBM) and subspace-splitting moment-matching MOR (SSMM-MOR)

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  • Business Process Modelling and Enterprise Improvement Analysis

    Publikacja

    The main trends in developing an approach and tools for business process modelling are discussed. Business Process Management (BPM) and BPM Notation (BPMN) are presented. Moreover, the possibilities of C2NIWA in a wide range of these tools running on a supercomputer are suggested. Firstly, the company development strategy can be planned . Secondly, quick and flexible changes of its processes can be modelled, analysed and implemented....

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  • Juices from untypical edible fruits as acidity regulators for food industry. Verification of health promoting properties. Comparison with typical acidity regulators.

    Publikacja

    Nowadays all kind of food additives, and among them acidity regulators, have become necessary components of most food products. Their role is lengthening shelf-life, improving the sensory properties and protecting food products from microbial contaminations. However, despite advantages, there are also some undesirable effects of use of food additives that have raised public concern recently. Therefore, food industry considers the...

  • Entrepreneurship in Virtual Economy: the Case of Currency One SA

    Publikacja

    Purpose: The scientific purpose of the study is an attempted synthesis of interpretation of “the virtual economy” and “the virtual environment” in the Polish and foreign literature on the subject. The cognitive purpose thereof is to offer an identification and a qualitative analysis of the factors that determine the development of e-entrepreneurship using an example of business practice. Methodology: The theoretical basis of the...

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  • Wybrane aspekty zachowań internautów a skuteczny proces komunikacji marketingowej

    Publikacja

    Celem artykułu jest przedstawienie sposobów pozyskiwania internetowych treści związanych z organizacjami lub produktami oraz dzielenia się nimi z innymi. W publikacji zwrócono uwagę na potrzebę zmiany postrzegania roli internautów w procesie komunikacji marketingowej. Ponadto, artykuł nawiązuje do koncepcji inbound marketing. Koncepcja ta dotyczy nie tylko przyciągania klientów do firmy i jej produktów. Chodzi w niej o by poprzez...

  • Gradient versus proper gradient homotopies

    Publikacja

    - Homology Homotopy and Applications - Rok 2021

    We compare the sets of homotopy classes of gradient and proper gradient vector fields in the plane. Namely, we show that gradient and proper gradient homotopy classi cations are essentially different. We provide a complete description of the sets of homotopy classes of gradient maps from R^n to R^n and proper gradient maps from R^2 to R^2 with the Brouwer degree greater or equal to zero.

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  • Comparison of thresholding algorithms for automatic overhead line detection procedure

    The article presents an overview of the thresholding algorithms. It compares the algorithms proposed by Pun, Kittler, Niblack, Huang, Rosenfeld, Remesh, Lloyd, Riddler, Otsu, Yanni, Kapur and Jawahar. Additionally, it was tested how the tuning of the Pun, Jawahar and Niblack methods affects the thresholding efficiency and proposed a combination of the Pun algorithm with a priori algorithm. All presented algorithms have been implemented...

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  • Juices from untypical edible fruits as acidity regulators for food industry. Verification of health promoting properties. Comparison with typical acidity regulators

    Publikacja
    • I. Koss

    - Rok 2011

    The purpose of this work was to verify possibility of using juices from selected fruits characterized by the high antioxidant potential as natural acidity regulators with improved nutritional properties. The tested fruits included: mirabelle plum, sea buckthorn, lemon and blueberry honeysuckle.The potentiometric titration was used to compare the effiacy of the juices as acidity regulators with citric acid, a widely used acidity...

  • Comparative modeling of shear localization in granular bodies with FEM and DEM

    Publikacja

    The intention of the paper is to compare the calculations of shear zones in granular bodies using two different approaches: a continuum and a discrete one. In the first case, the FEM based on a micro-polar hypoplastic constitutive law was used. In the second case, the DEM was taken advantage of, where contact moments were taken into account to model grain roughness. The comparative calculations were performed for a passive case...

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  • Optimizing FSO networks resilient to adverse weather conditions by means of enhanced uncertainty sets

    Publikacja

    - Optical Switching and Networking - Rok 2021

    This work deals with dimensioning of wireless mesh networks (WMN) composed of FSO (free space optics) links. Although FSO links realize broadband transmission at low cost, their drawback is sensitivity to adverse weather conditions causing transmission degradation on multiple links. Hence, designing such FSO networks requires an optimization model to find the cheapest configuration of link capacities that will be able to carry...

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  • Principles and Practices of Corporate Governance in the Global Economy

    Publikacja

    - Rok 2020

    The book places ownership at the centre of all relevant choices that the company makes. In particular, it addresses the issue of governance from the perspective of ownership, and in a broader and more articulated sense than most Anglo-Saxon studies do. The authors analyse the relationship between ownership, governance, and corporate strategy, with a dual objective. On the one hand, the aim is to identify the consistency relationships...

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  • Novel condition monitoring of induction motor bearings via motor current signature analysis

    Publikacja

    The paper authors are researching the assessment of bearing conditions in induction motors. The methods developed by the authors are based on measurements and analysis of the motor supply current, which is particularly attractive in the absence of access to the engine. The article provides an overview of selected methods of induction motor bearings diagnostic based on Motor Current Signature Analysis (MCSA). However, there is no...

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  • Efficient Gradient-Based Algorithm with Numerical Derivatives for Expedited Optimization of Multi-Parameter Miniaturized Impedance Matching Transformers

    Full-wave electromagnetic (EM) simulation tools have become ubiquitous in the design of microwave components. In some cases, e.g., miniaturized microstrip components, EM analysis is mandatory due to considera¬ble cross-coupling effects that cannot be accounted for otherwise (e.g., by means of equivalent circuits). These effects are particularly pronounced in the structures in¬volving slow-wave compact cells and their numerical...

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  • Parallel tabu search for graph coloring problem

    Publikacja

    Tabu search is a simple, yet powerful meta-heuristic based on local search that has been often used to solve combinatorial optimization problems like the graph coloring problem. This paper presents current taxonomy of patallel tabu search algorithms and compares three parallelization techniques applied to Tabucol, a sequential TS algorithm for graph coloring. The experimental results are based on graphs available from the DIMACS...

  • Generalized Gradient Equivariant Multivalued Maps, Approximation and Degree

    Publikacja

    Consider the Euclidean space Rn with the orthogonal action of a compact Lie group G. We prove that a locally Lipschitz G-invariant mapping f from Rn to R can be uniformly approximated by G-invariant smooth mappings g in such a way that the gradient of g is a graph approximation of Clarke’s generalized gradient of f . This result enables a proper development of equivariant gradient degree theory for a class of set-valued gradient...

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  • Minimal Sets of Lefschetz Periods for Morse-Smale Diffeomorphisms of a Connected Sum of g Real Projective Planes

    Publikacja

    - Rok 2022

    The dataset titled Database of the minimal sets of Lefschetz periods for Morse-Smale diffeomorphisms of a connected sum of g real projective planes contains all of the values of the topological invariant called the minimal set of Lefschetz periods, computed for Morse-Smale diffeomorphisms of a non-orientable compact surface without boundary of genus g (i.e. a connected sum of g real projective planes), where g varies from 1 to...

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  • Working in harmony with nature. Green office buildings in a present-day city

    Publikacja

    - GeoScape - Rok 2010

    Metropolis - as main point of people's migration, mostly because of work, have to face sustainable development as a strategy for the near future. This article describes possible ways leading to the best office building concepts in the design process. Searching for a workspace in harmony with nature is one of the aspects of a balanced development. The challenge is to create functional, compact, environmentally friendly and healthy...

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  • Application of the laser diode with central wavelength 975 nm for the therapy of neurofibroma and hemangiomas

    Publikacja

    - JOURNAL OF BIOMEDICAL OPTICS - Rok 2017

    This paper presents newly developed dermatological laser (with central wavelength 975 nm) for application in therapies requiring deep penetration of tissue, e.g. cutaneous (dermal) neurofibroma (Recklinghausen disease) and hemangiomas. This laser can work either in pulse or continues wave mode. Laser radiation is transmitted toward the application region by optical fiber with a diameter of 0.6 mm. The compact design of the laser...

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  • An algorithm for enhancing macromodeling in finite element analysis of waveguide components

    Publikacja

    - Rok 2017

    An algorithm for enhancing the finite element method with local model order reduction is presented. The proposed technique can be used in fast frequency domain simulation of waveguide components and resonators. The local reduction process applied to cylindrical subregions is preceded by compression of the number of variables on its boundary. As a result,the finite element large system is converted into a very compact set of linear...

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  • Multi-level Virtualization and Its Impact on System Performance in Cloud Computing

    The results of benchmarking tests of multi-level virtualized environments are presented. There is analysed the performance impact of hardware virtualization, container-type isolation and programming level abstraction. The comparison is made on the basis of a proposed score metric that allows you to compare different aspects of performance. There is general performance (CPU and memory), networking, disk operations and application-like...

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  • Stereoscopy in Graphics APIs for CAVE Applications

    The paper compares the advantages and disadvantages of a variety of Graphics Application Programming Interfaces (APIs) from the perspective of obtaining stereoscopy in applications written for a CAVE virtual reality environment. A number of problems have been diagnosed and an attempt has been made to solve them using OpenGL, DirectX 11 and 12, Vulkan, as well as the Unity Engine which can internally use DirectX, OpenGL and Vulkan,...

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  • A method of measuring RLC components for microcontroller systems

    Publikacja

    A new method of measuring RLC components for microcontroller systems dedicated to compact smart impedance sensors based on a direct sensor-microcontroller interface is presented. In the method this direct interface composed of a reference resistor connected in series with the tested sensor impedance is stimulated by a square wave generated by the microcontroller, and then its voltage response is sampled by an internal ADC of the...

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  • Design of Inner Gate for CRIST Shipyard Dry Dock

    The paper deals with a removable steel inner gate which was designed to separate two parts of a dry dock of about 70 m in width and 380 m in length. The gate allows for independent assembly of ship structures in two separated parts of the dock. The fore part of the dock can be flooded while the after part is dry. Tthe gate was designed by IDEK Company Ltd in 2011 and it was soon constructed and used by CRIST Shipyard in Gdynia.

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  • Mashup Approaches for Improving Service Oriented Business Scenarios

    Publikacja

    Two kinds of business scenarios are considered: application- and service-oriented. It is shown that the former are more flexible and easier reconfigurable for both traditional (human-oriented) and IT services. Moreover, complex IT services can be created by simple IT services using the modern mashup technology. It is the reason why such business scenarios can be modeled by BPMN in much easier ways. A simple example of a supply...

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  • Knowledge management approaches among KIBS companies and their determinants – case study analysis

    Publikacja

    - Rok 2018

    This paper aims to present knowledge management (KM) approaches manifested by knowledge intensive business service (KIBS) companies together with their potential determinants (company size, type of services offered, and organizational structure). In particular, two types of approaches have been selected and examined, i.e. emergent KM approach and deliberate KM approach. Indeed, although KM approaches have been abundantly investigated...

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  • The added value of using the HEPA PAT for physical activity policy monitoring: a four-country comparison

    Publikacja
    • P. Gelius
    • S. Messing
    • S. Forberger
    • J. Lakerveld
    • F. Mansergh
    • W. Wendel-Vos
    • J. Żukowska
    • C. Woods

    - Health Research Policy and Systems - Rok 2021

    Background Public policy is increasingly recognized as an important component of physical activity promotion. This paper reports on the current status of physical activity policy development and implementation in four European countries based on the Health-Enhancing Physical Activity Policy Audit Tool (HEPA PAT) developed by WHO. It compares the findings to previous studies and discusses the general utility of this tool and its...

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  • Evaluation of the factors influencing business bankruptcy risk in Poland

    Publikacja

    This article is devoted to the issue of assessing the causes of business failure. The presented studies answer two research questions – what are the causes of corporate bankruptcies in Poland and how to more efectively predict the scale of bankruptcies in the country. The author has conducted a study to analyze the specic endogenous and exogenous causes of company bankruptcy depending on the type of the bankruptcy with consideration...

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  • The Usefulness of Cyclic Diamidines with Different Core-substituents as Antitumor Agents

    Publikacja

    A series of related polycationic compds. has been screened for potential antitumor activity by the NCI's in vitro testing (one dose primary anticancer assay and the NCI-60 full panel screening).  The GI50 values of triazines 3 and 4 are on av. 1.9 μM and 2.4 μM, resp.  Furan 8 deserves mention too (1.9 μM).  The biol. test results showed that carbazole 10 possessed cytotoxic activity in the nanomolar range, much better than...

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  • Price Diversification

    Publikacja

    The price diversification is a complex phenomenon. We show that price discrimination can have both positive and negative effects. The final result depends whether it makes competition more intense. As far as legal procedure is cocerned it is recommended to focus on the effects of compan's actions rather than on the form that these actions may take. There is a need to understand and distinguish between price discrimination as the...

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  • Low-Cost Surrogate Modeling of Miniaturized Microwave Components Using Nested Kriging

    In the paper, a recently reported nested kriging methodology is employed for modeling of miniaturized microwave components. The approach is based on identifying the parameter space region that contains high-quality designs, and, subsequently, rendering the surrogate in this subset. The results obtained for a miniaturized unequal-power-split rat-race coupler and a compact three-section impedance transformer demonstrate reliability...

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  • Diagnostic Models and Estimators for LDI in Transmission Pipelines

    Publikacja

    This article considers and compares four analytical models of the pipeline flow process for leak detection and location tasks. The synthesis of these models is briefly outlined. Next, the methodology for generating data and diagnosing pipes is described, as well as experimental settings, assumptions and implemented scenarios. Finally, the quality of model-based diagnostic estimators has been evaluated for their bias, standard deviations...

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  • A 3-dB coupler with UC-PBG structure

    Publikacja

    Przedstawiono nową konstrukcję sprzęgacza z liniami paskowymi sprzężonymi szerokim bokiem oraz zmodyfikowaną warstwą metalizacji masy. Modyfikacja metalizacji polega na periodycznym wytrawieniu dwuwymiarowej struktury szczelin, nazywanej strukturą uniplanarnej zwartej przerwy fotonicznej (UC-PBG: Uniplanar Compact Photonic BandGap). Potwierdzono przewidywane wcześniej zjawisko spowolnienia fali oraz powiększenia wielkości sprzężenia...

  • Guitar String Sound Retrieved from Moving Pixels

    The aim of this study was to develop a method of visual recording and analyzing the vibrations of guitar strings using high-speed cameras and dedicated video processing algorithms. The recording of a plucked string reveals the way in which the deformations propagate, composing the standing and travelling wave. The paper compares the results for a few selected models of classical and acoustic guitars, and it involves processing...

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  • Data Mining Applications and Methods in Medicine

    Publikacja

    In this paper we describe the research area of data mining and its applications in medicine. The origins of data mining and its crucial features are shortly presented. We discuss the specificity of medicine as an application area for computer systems. Characteristic features of the medical data are investigated. Common problems in the area are also presented as well as the strengths and capabilities of the data mining methods....

  • THE IPV4 TO IPV6 MIGRATION OF APPLICATIONS AND SERVICE

    This article presents the problems related to IPv4 to IPv6 migration of applications supporting network services. It summarizes the needs of executing such migration. It shows the basic problems of automating the migration process, having defined the basic terms, i.e.: a network service, a network application. It shows a sample implementation of the automation of the migration process between IP technologies for selected network...

  • Być czy mieć? Hierarchia kapitałów w wybranych przedsiębiorstwach ICT na Pomorzu

    Publikacja

    Prezentowany artykuł stanowi podsumowanie pierwszej, początkowej fazy konstruowania koncepcji wykorzystującej przekształconą teorię kapitałów Pierre’a Bourdieu w analizie działań przedsiębiorstw. Jej sednem jest podział dostępnych przedsiębiorstwom zasobów na cztery podstawowe typy odpowiadające wyróżnionym typom kapitału, a więc: kapitałowi ekonomicznemu, społecznemu, kulturowemu i symbolicznemu oraz założenie, zgodnie z którym...

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  • Wycena środowiska w aspekcie odpowiedzialności moralnej

    Publikacja

    - Rok 2003

    the article '' the pricing of environment in the moral responsibility context" presents ethical protection of natural environment within sustainable development paradigm as well as the problem of individual, moral responsibility in the liberal civilization. it contains different opinions on the environmental ethics, compares flat and deep ecology as well as environmental and ecological economy; it characterizes methods of economic...

  • Evaluation of Six Degrees of Freedom 3D Audio Orchestra Recording and Playback using multi-point Ambisonic interpolation

    Publikacja
    • T. Ciotucha
    • A. Rumiński
    • T. Żernicki
    • B. Mróz

    - Scopus - Rok 2021

    This paper describes a strategy for recording sound and enabling six-degrees-of-freedom playback, making use of multiple simultaneous and synchronized Higher Order Ambisonics (HOA) recordings. Such a strategy enables users to navigate in a simulated 3D space and listen to the six-degrees-of-freedom recordings from different perspectives. For the evaluation of the proposed approach, an Unreal Engine-based navigable 3D audiovisual...

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