Wyniki wyszukiwania dla: ENTROPY, RANDOM VARIABLES, INFORMATION THEORY - MOST Wiedzy

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Wyniki wyszukiwania dla: ENTROPY, RANDOM VARIABLES, INFORMATION THEORY

Wyniki wyszukiwania dla: ENTROPY, RANDOM VARIABLES, INFORMATION THEORY

  • Sensitivity analysis of free torsional vibration frequencies of thin-walled laminated beams under axial load

    The paper addresses sensitivity analysis of free torsional vibration frequencies of thin-walled beams of bisymmetric open cross-section made of unidirectional fibre-reinforced laminate. The warping effect and the axial end load are taken into account. The consideration is based upon the classical theory of thin-walled beams of non-deformable cross-section. The first-order sensitivity variation of the frequencies is derived with...

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  • A robust sliding mode observer for non-linear uncertain biochemical systems

    A problem of state estimation for a certain class of non-linear uncertain systems has been addressed in this paper. In particular, a sliding mode observer has been derived to produce robust and stable estimates of the state variables. The stability and robustness of the proposed sliding mode observer have been investigated under parametric and unstructured uncertainty in the system dynamics. In order to ensure an unambiguous non-linear...

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  • A breath of fresh air - social cognitive career theory in studying entrepreneurial intentions

    A pinch of robustness and a pinch of freshness create an interesting story. That is why this study focuses on entrepreneurial intentions from an alternative theoretical perspective in an underexplored context. In this paper, it is argued that social cognitive career theory is relevant to the study of individual entrepreneurial cognition and behaviour, and it offers a solid framework in entrepreneurship research. This paper expands...

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  • Quantum security and theory of decoherence

    Publikacja

    We sketch a relation between two crucial, yet independent, fields in quantum information research, viz. quantum decoherence and quantum cryptography. We investigate here how the standard cryptographic assumption of shielded laboratory, stating that data generated by a secure quantum device remain private unless explicitly published, is disturbed by the einselection mechanism of quantum Darwinism explaining the measurement process...

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  • What matters most to patients? On the Core Determinants of Patient Experience from Free Text Feedback

    Publikacja

    - Rok 2021

    Free-text feedback from patients is increasingly used for improving the quality of healthcare services and systems. A major reason for the growing interest in harnessing free-text feedback is the belief that it provides richer information about what patients want and care about. The use of computational approaches such as structural topic modelling for analysing large unstructured textual data such as free-text feedback from patients...

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  • Synteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu

    Publikacja

    - Rok 2016

    Synteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu stanowi cel niniejszej monografii. Praca zawiera podstawowe informacje na temat modelowania układu napędowego z maszyną indukcyjną klatkową zasilaną z falownika prądu. Przedstawiono informacje na temat linearyzacji nieliniowych obiektów. Na pod-stawie metody syntezy strukturalnej opracowano nowe transformacje do postaci zmien-nych multiskalarnych,...

  • Towards Resource Theory of Coherence in Distributed Scenarios

    Publikacja

    - Physical Review X - Rok 2017

    The search for a simple description of fundamental physical processes is an important part of quantum theory. One example for such an abstraction can be found in the distance lab paradigm: if two separated parties are connected via a classical channel, it is notoriously difficult to characterize all possible operations these parties can perform. This class of operations is widely known as local operations and classical communication....

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  • Simulating coherent light propagation in a random scattering materials using the perturbation expansion

    Multiple scattering of a coherent light plays important role in the optical metrology. Probably the most important phenomenon caused by multiple scattering are the speckle patterns present in every optical imaging method based on coherent or partially coherent light illumination. In many cases the speckle patterns are considered as an undesired noise. However, they were found useful in various subsurface imaging methods such as...

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  • Zero-knowledge convincing protocol on quantum bit is impossible

    Publikacja

    - Quantum Journal - Rok 2017

    It is one of fundamental features of quantum formalism that o n one hand it provides a new infor- mation processing resources and on the other hand puts funda mental constraints on the processing of quantum information implying “no-go” theorems for cloni ng [1–3], bit commitment [4, 5] and deleting [6] in quantum theory. Here we ask about possibilit y of “zero knowledge” scenario which, for its simplicity, can be considered as...

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  • Application of multivariate statistics in assessment of green analytical chemistry parameters of analytical methodologies

    Publikacja

    - GREEN CHEMISTRY - Rok 2013

    The study offers a multivariate statistical analysis of a dataset, including the major metrological, “greenness” and methodological parameters of 43 analytical methodologies applied for aldrin determination (a frequently analyzed organic compound) in water samples. The variables (parameters) chosen were as follows: metrological (LOD, recovery, RSD), describing the “greenness” (amount of the solvent used, amount of waste generated)...

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  • Enhancing women’s engagement in economic activities through information and communication technology deployment: evidence from Central–Eastern European countries

    This study takes a macro perspective to examine the associations between the economic deployment of information and communication technology (ICT), women’s labor market participation, and economic growth in Central–Eastern European countries between 1990 and 2017. We use data extracted from World Bank Development Indicators, World Development Reports, and the World Telecommunication/ICT Indicators Database. Our methodological framework...

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  • TRANSFORMATION OF THE BANKING SECTOR AS AN ELEMENT OF ECONOMIC TRANSFORMATION IN SOUTH-EAST EUROPE

    The issue of stability in economy is essential, both in theoretical as well as in practical discussion. It is especially important in an environment of economic transformation. The aim of the article is to assess the economic stability during the transformation of the south-east region of Europe over a period of 19 years (1996 – 2014), and the mutual relation between the economic stability and the transformation process, including...

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  • Variable Speed AC Drives with Inverter Output Filters

    Publikacja

    - Rok 2015

    The advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...

  • Appendix E

    Publikacja

    - Rok 2015

    The advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...

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  • Generic appearance of objective results in quantum measurements

    Publikacja

    - PHYSICAL REVIEW A - Rok 2017

    Measurement is of central interest in quantum mechanics as it provides the link between the quantum world and the world of everyday experience. One of the features of everyday experience is its robust, objective character, contrasting the delicate nature of quantum systems. Here we analyze in a completely model-independent way the celebrated von Neumann measurement process, using recent techniques of information flow, studied in...

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  • Application Isssues of the Semi-Markov Reliability Model

    Publikacja

    Predicting the reliability of marine internal combustion engines, for instance, is of particular importance, as it makes it possible to predict their future reliability states based on the information on the past states. Correct reliability prediction is a complex process which consists in processing empirical results obtained from operating practice, complemented by analytical considerations. The process of technical state changes...

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  • Extensions of ETSI performance measurements methodology for statistical results analysis =Rozszerzenia metodologii pomiarów wydajności zaproponowanej przez ETSI przy statystycznej analizy wyników

    Next Generation Network (NGN) architecture was proposed by International Telecommunication Union Telecommunication Standardization Sector (ITU-T) to deliver telecommunication services satisfying the needs of modern society for an access to information. The core of NGN service stratum are IP Multimedia Subsystem (IMS) elements acting as service controls units. To assess performance of IMS components, European Telecommunications...

  • Simulation of Direct-Sequence Spread Spectrum Data Transmission System for Reliable Underwater Acoustic Communications

    Underwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. It is a particularly difficult task in a shallow underwater channel in which the signal suffers from strong time dispersion due to multipath propagation and refraction phenomena. The direct-sequence spread spectrum technique (DSSS) applied successfully in the latest standards...

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  • Instructor Presence in Video Lectures: Preliminary Findings From an Online Experiment

    Publikacja

    - IEEE Access - Rok 2021

    Motivation. Despite the widespread use of video lectures in online and blended learning environments, there is still debate whether the presence of an instructor in the video helps or hinders learning. According to social agency theory, seeing the instructor makes learners believe that s/he is personally teaching them, which leads to deeper cognitive processing and, in turn, better learning outcomes. Conversely, according to cognitive...

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  • How do personality traits influence Open Government Data (OGD) adoption and usage? Investigating the indirect and moderating effects

    Publikacja
    • N. Rizun
    • C. H. Alexopoulos
    • S. Saxena
    • F. Kleiman
    • R. Matheus

    - Rok 2023

    Open Government Data (OGD) research has focused for a long on the adoption and usage from the perspectives of users across different contexts. The underlying rationale for this specific focus is that OGD initiatives are undertaken to further citizen engagement with OGD for value generation and innovation purposes. Conceding that usage propensity is different across individuals, it is important to understand the influence of personality...

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  • Parametric optimization of sandwich composite footbridge with U-shaped cross-section

    Publikacja

    Parametric optimization of sandwich composite footbridge was presented in the paper. Composite footbridge has 14,5 m long and has U-shaped cross-section with inner dimensions 2,6 × 1,3 m. The sandwich structure in made from GFRP laminate as a faces and PET foam as a core. The aim of analysis was to minimize the mass of the new footbridge that can lead to minimize the cost of structure. After optimization was conducted, the new...

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  • Nonlocalized thermal behavior of rotating micromachined beams under dynamic and thermodynamic loads

    Publikacja

    Rotating micromachined beams are one of the most practical devices with several applications from power generation to aerospace industries. Moreover, recent advances in micromachining technology have led to huge interests in fabricating miniature turbines, gyroscopes and microsensors thanks to their high quality/reliability performances. To this end, this article is organized to examine the axial dynamic reaction of a rotating...

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  • Computational analysis of an infinite magneto-thermoelastic solid periodically dispersed with varying heat flow based on non-local Moore–Gibson–Thompson approach

    Publikacja

    - CONTINUUM MECHANICS AND THERMODYNAMICS - Rok 2021

    In this investigation, a computational analysis is conducted to study a magneto-thermoelastic problem for an isotropic perfectly conducting half-space medium. The medium is subjected to a periodic heat flow in the presence of a continuous longitude magnetic field. Based on Moore–Gibson–Thompson equation, a new generalized model has been investigated to address the considered problem. The introduced model can be formulated by combining...

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  • A CONTEXT IN RECOMMENDER SYSTEMS

    Publikacja

    - Rok 2016

    Recommender systems aim to propose potentially interesting items to a user based on his preferences or previous interaction with the system. In the last decade, researcher found out that known recommendation techniques are not sufficient to predict user decisions. It has been noticed that user preferences strongly depend on the context in which he currently is. This raises new challenges for the researchers such as how to obtain...

  • Modelling of residential sales price with kriging using different distance metrics in different correlation functions

    Publikacja

    - Gazi University Journal of Science - Rok 2016

    The modelling and estimation of sales prices based on economical conditions are important for housing sector especially in developing countries. Analysts are focused on the subject to analyze price movements and estimate the future trend of the sales prices for housing sector. In this study, we tried to generate a robust and efficient model related to the subject. Firstly, we investigated economic variables affecting housing sales...

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  • Firing map of an almost periodic input function

    Publikacja

    In mathematical biology and the theory of electric networks the firing map of an integrate-and-fire system is a notion of importance. In order to prove useful properties of this map authors of previous papers assumed that the stimulus function f of the system ẋ = f(t,x) is continuous and usually periodic in the time variable. In this work we show that the required properties of the firing map for the simplified model ẋ = f(t) still...

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  • Observation Value Analysis – Integral Part of Bayesian Diagnostics

    The decision making process, in general, is understood as a process of selecting one of the available solutions to the problem. One of possible approaches supporting the process is Bayesian statistical decision theory providing a mathematical model to make decisions of a technical nature in conditions of uncertainty. Regarding above, a detailed subject of the research is to analyze the value of the observation, which is a part...

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  • Influence of Natural Conditions on the Imaging of the Bottom of the Gdańsk Bay by Means of the Side Scan Sonar

    The interest in underwater resources is the reason for the development of modern hydroacoustic systems, including side sonars, which find numerous applications such as: research of seabed morphology and sediment characteristics, preparation of sea sediment maps, and even in special cases of biocenoses such as sea grass meadows, detection of specific targets at the bottom such as shipwrecks, mines, identification of suitable sites...

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  • Semantic Analysis and Text Summarization in Socio-Technical Systems

    Publikacja

    - Rok 2018

    In this chapter the authors present the results of the development the methodology for increasing the reliability of the functioning of the Socio-Technical System. The existed methods and algorithms for processing unstructured (textual) information were studied. Taking into account noted above strengths and weaknesses of Discriminant and Probabilistic approaches of Latent Semantic Relations analysis in of the summarization projection...

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  • Fast Low-fidelity Wing Aerodynamics Model for Surrogate-Based Shape Optimization

    Publikacja

    Variable-fidelity optimization (VFO) can be efficient in terms of the computational cost when compared with traditional approaches, such as gradient-based methods with adjoint sensitivity information. In variable-fidelity methods, the directoptimization of the expensive high-fidelity model is replaced by iterative re-optimization of a physics-based surrogate model, which is constructed from a corrected low-fidelity model. The success...

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  • Principles of target DNA cleavage and the role of Mg2+ in the catalysis of CRISPR–Cas9

    Publikacja
    • Ł. Nierzwicki
    • P. R. Arantes
    • M. Jinek
    • G. Lisi
    • G. Palermo
    • K. East
    • J. Binz
    • R. Vsu
    • A. Mohd
    • E. Skeens
    • M. Pacesa

    - Nature Catalysis - Rok 2022

    At the core of the CRISPR–Cas9 genome-editing technology, the endonuclease Cas9 introduces site-specific breaks in DNA. However, precise mechanistic information to ameliorate Cas9 function is still missing. Here, multimicrosecond molecular dynamics, free energy and multiscale simulations are combined with solution NMR and DNA cleavage experiments to resolve the catalytic mechanism of target DNA cleavage. We show that the conformation...

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  • Zastosowanie trendów przełącznikowych w analizie płac realnych w Polsce

    Streszczenie W początkowej części artykułu zostały przedstawione i omówione informacje o poziomie miesięcznych nominalnych płac (WN) oraz indeksie cen dóbr konsumpcyjnych (ICK) w gospodarce polskiej w latach 1995-2015. Następnie opisano poziomy realnych płac (W) wyrażone w cenach roku 2015. Na bazie tych informacji przedstawiono i przedyskutowano zagadnienia dotyczące rocznych przyrostów płac realnych oraz ich rocznych stóp wzrostu....

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  • Selective Harmonic Elimination PWM For a Cascaded Multi-level Inverter

    Publikacja

    - Rok 2020

    This paper deals with the selective harmonic elimination pulse width modulation (SHE-PWM) technique. This technique is used for the elimination of selected dominant low order harmonics in the multi-level inverter output voltage. The presence of these harmonics is the essential drawback of such kind of inverters; especially when it is used for the control of different AC drivers. The SHE-PWM is based...

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  • Incorporating installation effects into the probability analysis of controlled modulus columns

    Publikacja

    This technical report presents the probabilistic analysis which integrates the Monte Carlo simulation (MCS) with random field theory to model the load–displacement behavior of Controlled Modulus Columns (CMCs) in overconsolidated Poznań clay. Presented study focuses on the practical aspects of statistical analysis of geotechnical data, numerical model development, and results evaluation. Variability and spatial distribution of...

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  • Set of Experience and Decisional DNA: Experience-Based Knowledge Structures

    Publikacja

    - Rok 2020

    This chapter presents a description of Set of Experience Knowledge Structure (SOEKS) and Decisional DNA (DDNA), argumentation for a knowledge representation, composition, configuration and metrics. SOEKS is a combination of filtered and amalgamated information obtained from formal decision events. It facilitates effective explicit representation of decisional experience taken from different technologies. SOEKS comprises variables,...

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  • THE ROLE OF INFERENCE IN MOBILE MEDICAL APPLICATION DESIGN

    Publikacja

    - Rok 2021

    In the early 21st century, artificial intelligence began to be used to process medical information. However, before this happened, predictive models used in healthcare could only consider a limited number of variables, and only in properly structured and organised medical data. Today, advanced tools based on machine learning techniques - which, using artificial neural networks, can explore extremely complex relationships - and...

  • JamesBot - an intelligent agent playing StarCraft II

    Publikacja

    The most popular method for optimizing a certain strategy based on a reward is Reinforcement Learning (RL). Lately, a big challenge for this technique are computer games such as StarCraft II which is a real-time strategy game, created by Blizzard. The main idea of this game is to fight between agents and control objects on the battlefield in order to defeat the enemy. This work concerns creating an autonomous bot using reinforced...

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  • Excited state properties of a series of molecular photocatalysts investigated by time dependent density functional theory.

    Publikacja

    Time dependent density functional theory calculations are applied on a series of molecular photocatalysts of the type [(tbbpy)2M1(tpphz)M2X2]2+ (M1 = Ru, Os; M2 = Pd, Pt; X = Cl, I) in order to provide information concerning the photochemistry occurring upon excitation of the compounds in the visible region. To this aim, the energies, oscillator strengths and orbital characters of the singlet and triplet excited states are investigated....

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  • Agent-based social network as a simulation of a market behaviour

    Publikacja

    - Rok 2010

    Recent years and the outbreak of world's economic crisis in 2008 proved the crucial importance of reliable analysis of market dynamics. However, werarely apply models of proper detail level (the global prosperity forecast of 2007 can be seen as a grim proof). The behaviour of individuals and companies is far from being ideal and rational. Many claims that the economic paradigm of rational expectations (coming from J. Muth and R....

  • Quantum metrology: Heisenberg limit with bound entanglement

    Publikacja

    - PHYSICAL REVIEW A - Rok 2015

    Quantum entanglement may provide a huge boost in the precision of parameter estimation. However, quantum metrology seems to be extremely sensitive to noise in the probe state. There is an important still open question: What type of entanglement is useful as a resource in quantum metrology? Here we raise this question in relation to entanglement distillation. We provide a counterintuitive example of a family of bound entangled states...

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  • Dynamic Bayesian Networks for Symbolic Polyphonic Pitch Modeling

    Publikacja

    Symbolic pitch modeling is a way of incorporating knowledge about relations between pitches into the process of an- alyzing musical information or signals. In this paper, we propose a family of probabilistic symbolic polyphonic pitch models, which account for both the “horizontal” and the “vertical” pitch struc- ture. These models are formulated as linear or log-linear interpo- lations of up to fi ve sub-models, each of which is...

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  • The Use of Information and Communication Technologies in Cluster Organizations

    Publikacja

    - Rok 2019

    The purpose of the paper is to explore how cluster organizations (COs) take advantage of Information and Communication Technologies (ICT). The paper addresses the research question: “How do cluster organizations take advantage of ICT in fulfilling their main roles?”. The research was carried out in the first half of 2016 in four purposefully selected cluster organizations. The main research strategy involved Grounded Theory; the...

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  • ADAPTIVE BACKSTEPPING TRACKING CONTROL FOR OVER-ACTUATED DP MARINE VESSEL WITH INERTIA UNCERTAINTIES

    Designing a tracking control system for an over-actuated dynamic positioning marine vessel in the case of insufficient information on environmental disturbances, hydrodynamic damping, Coriolis forces and vessel inertia characteristics is considered. The designed adaptive MIMO backstepping control law with control allocation is based on Lyapunov control theory for cascaded systems to guarantee stabilization of the marine vessel...

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  • Parametric method applicable in assessing breakout force and time for lifting slender bodies from seabed

    Publikacja

    The article presents a parametric method applicable in assessing the suction force of a slender body to the seabed, and prognosing the body extrication time. Along with the body weight in water, the information on the suction force is essential for assessing the force needed to lift the object from the seabed. Based on the Foda theory and the resulting integral equation, which relates the maximum suction force with basic parameters...

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  • Negative result about the construction of genuinely entangled subspaces from unextendible product bases

    Publikacja

    Unextendible product bases (UPBs) provide a versatile tool with various applications across different areas of quantum information theory. Their comprehensive characterization is thus of great importance and has been a subject of vital interest for over two decades now. An open question asks about the existence of UPBs, which are genuinely unextendible, i.e., they are not extendible even with biproduct vectors. In other words,...

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  • Deep Learning: A Case Study for Image Recognition Using Transfer Learning

    Publikacja

    - Rok 2021

    Deep learning (DL) is a rising star of machine learning (ML) and artificial intelligence (AI) domains. Until 2006, many researchers had attempted to build deep neural networks (DNN), but most of them failed. In 2006, it was proven that deep neural networks are one of the most crucial inventions for the 21st century. Nowadays, DNN are being used as a key technology for many different domains: self-driven vehicles, smart cities,...

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  • Deep Learning

    Publikacja

    - Rok 2021

    Deep learning (DL) is a rising star of machine learning (ML) and artificial intelligence (AI) domains. Until 2006, many researchers had attempted to build deep neural networks (DNN), but most of them failed. In 2006, it was proven that deep neural networks are one of the most crucial inventions for the 21st century. Nowadays, DNN are being used as a key technology for many different domains: self-driven vehicles, smart cities,...

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  • Quantum Coherence as a Resource

    Publikacja
    • A. Streltsov
    • G. Adesso
    • M. B. Plenio

    - REVIEWS OF MODERN PHYSICS - Rok 2017

    The coherent superposition of states, in combination with the quantization of observables, represents one of the most fundamental features that mark the departure of quantum mechanics from the classical realm. Quantum coherence in many-body systems embodies the essence of entanglement and is an essential ingredient for a plethora of physical phenomena in quantum optics, quantum information, solid state physics, and nanoscale thermodynamics....

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  • Risk Modelling with Bayesian Networks - Case Study: Construction of Tunnel under the Dead Vistula River in Gdansk

    The process of decision-making in public procurement of construction projects during the preparation and implementation phases ought to be supported by risk identification, assessment, and management. In risk assessment one has to take into account factors that lead to risk events (background info), as well as the information about the risk symptoms (monitoring info). Typically once the risks have been assessed a decision-maker...

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  • Networkig activities of general judiciary - from theory to practice

    Publikacja

    - e-mentor - Rok 2018

    Over the last three decades, networks - as a field of research - have acquired a significant place among management sciences. Unfortunately, in the judiciary they have become a subject of more careful analyses only recently, which resulted in a large discrepancy of knowledge - both in theory and in its practical adaptation for the needs of the courts. In order to fill this cognitive gap, an attempt was made to identify levels of...

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