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Wyniki wyszukiwania dla: NETWORK RESOURCE PROVISIONING

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Wyniki wyszukiwania dla: NETWORK RESOURCE PROVISIONING

  • Supply current signal and artificial neural networks in the induction motor bearings diagnostics

    Publikacja

    This paper contains research results of the diagnostics of induction motor bearings based on measurement of the supply current with usage of artificial neural networks. Bearing failure amount is greater than 40% of all engine failures, which makes their damage-free operation crucial. Tests were performed on motors with intentionally made bearings defects. Chapter 2 introduces the concept of artificial neural networks. It presents...

  • Simulation model for evaluation of QOS dynamic routing

    Publikacja

    - Rok 2009

    Current informational networks use a large variety of technologies to support data exchange. Most of them are focused on IP protocol and include mechanisms which by definition should supply demanded QoS. One of those mechanisms is efficient path calculation - routing. Traffic offered to the network can change very rapidly in short term. Routing should support such traffic changes and all the time calculate valid paths in terms...

  • Minimizing Distribution and Data Loading Overheads in Parallel Training of DNN Acoustic Models with Frequent Parameter Averaging

    Publikacja

    In the paper we investigate the performance of parallel deep neural network training with parameter averaging for acoustic modeling in Kaldi, a popular automatic speech recognition toolkit. We describe experiments based on training a recurrent neural network with 4 layers of 800 LSTM hidden states on a 100-hour corpora of annotated Polish speech data. We propose a MPI-based modification of the training program which minimizes the...

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  • The role of EMG module in hybrid interface of prosthetic arm

    Nearly 10% of all upper limb amputations concern the whole arm. It affects the mobility and reduces the productivity of such a person. These two factors can be restored by using prosthetics. However, the complexity of human arm makes restoring its basic functions quite difficult. When the osseointegration and/or targeted muscle reinnervation (TMR) are not possible, different modalities can be used to control the prosthesis. In...

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  • Optimising Sequencing Batch Reactor Operation Cycle Planning Using Evolutionary Algorithm

    Publikacja

    The objective of this research was to optimise the operation cycle of the Sequencing Batch Reactor (SBR). Appropriate time balances of aerobic to anaerobic phases, as well as a set dissolved oxygen level are the key to ensuring the quality of effluent from the wastewater treatment process. The proposal to solve this optimisation problem was based on multi-objective optimisation using an evolutionary multi-objective optimisation...

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  • Simple analytical method for total biogenic amines content determination in wine using a smartphone

    A simple, fast, and green smartphone-based procedure for total biogenic amines content determination in wine was developed and validated. Sample preparation and analysis were simplified to make the method suitable for routine analyses even in resource-scarce settings. The commercially available S0378 dye and smartphone-based detection were used for this purpose. The developed method has satisfactory figures of merit for putrescine...

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  • DAB vs DAB+ Radio Broadcasting: a Subjective Comparative Study

    Publikacja

    In the age of digital media, delivering high quality content to consumers is one of the most demanding tasks. There exist numerous broadcasting standards, with different pros and cons, and the DAB/DAB (Digital Audio Broadcasting) system is one of the most popular among them. From an engineer’s perspective, efficient resource management under limited bandwidth conditions has always been a challenge. In this paper a subjective quality...

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  • Superadditivity of two quantum information resources

    Publikacja

    - Science Advances - Rok 2017

    Entanglement is one of the most puzzling features of quantum theory and a principal resource for quantum information processing. It is well known that in classical information theory, the addition of two classical information resources will not lead to any extra advantages. On the contrary, in quantum information, a spectacular phenomenon of the superadditivity of two quantum information resources emerges. It shows that quantum...

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  • Green, simple analytical method for total biogenic amines content determination in wine using spectrophotometry

    Publikacja

    A simple, green and equitable procedure for total biogenic amines (BAs) content determination was developed. The scientific novelty lies in the use of commercially available S 0378 dye, the reaction of which with BAs results in a colour change of the solution. Sample preparation and analysis were simplified to make the method suitable for routine analyses even in resource-scarce settings. The optimization of the method was carried...

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  • Message Inter-Arrival and Inter-Departure Time Distributions in IMS/NGN Architecture

    Publikacja

    - Rok 2012

    Currently is it assumed that requirements of the information society for delivering multimedia services will be satisfied by the Next Generation Network (NGN) architecture, which includes elements of the IP Multimedia Subsystem (IMS) solution. In order to guarantee Quality of Service (QoS), NGN has to be appropriately designed and dimensioned. Therefore, proper traffic models should be proposed and applied. This requires determination...

  • Distributed protection against non-cooperative node behavior in multi-hop wireless networks

    Publikacja

    An important security problem in today's distributed data networks is the prevention of non-cooperative behavior i.e., attacks consisting in the modification of standard node operation to gain unfair advantage over other system nodes. Such a behavior is currently feasible in many types of computer networks whose communication protocols are designed to maximize the network performance assuming full node cooperation. Moreover, it...

  • Dynamic unattended measurement based routing algorithm for diffServ architecture

    Publikacja

    - Rok 2010

    Dynamic routing is very important in terms of assuring QoS in today's packet networks especially for streaming and elastic services. Existing solutions dedicated to dynamic routing are often too complicated and seem to be not usable in real time traffic scenarios where transferred traffic may vary significantly. This was the main reason for research and new routing mechanism proposal which should apply to today's packet networks....

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  • SMART GRID TECHNOLOGIES IN ELECTRIC POWER SUPPLY SYSTEMS OF PUBLIC TRANSPORT

    Publikacja

    Nowadays the issue of electric energy saving in public transport is becoming a key area of interest which is connected both with a growth in environmental awareness of the society and an increase in the prices of fuel and electricity. It can be achieved by improving the usage of regenerative breaking. In 2016 the Przedsiębiorstwo Komunikacji Trolejbusowej (PKT, Trolleybus Transport Company) in Gdynia began practical implementation...

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  • RECODIS: Resilient Communication Services Protecting End-user Applications from Disaster-based Failures

    Publikacja
    • J. Rak
    • D. Hutchison
    • E. Calle
    • T. Gomes
    • M. Gunkel
    • P. Smith
    • J. Tapolcai
    • S. Verbrugge
    • L. Wosinska

    - Rok 2016

    Disaster-based failures can seriously disrupt any communication network, making its services unavailable. Such disruptions may be caused by natural disasters, technology-related failures, or malicious attacks, and they are observably increasing in number, intensity and scale. When network services that are a part of critical infrastructure become unavailable, commercial and/or societal problems are inevitable. The issue of limiting...

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  • Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm

    Publikacja

    A problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...

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  • A novel approach exploiting properties of convolutional neural networks for vessel movement anomaly detection and classification

    The article concerns the automation of vessel movement anomaly detection for maritime and coastal traffic safety services. Deep Learning techniques, specifically Convolutional Neural Networks (CNNs), were used to solve this problem. Three variants of the datasets, containing samples of vessel traffic routes in relation to the prohibited area in the form of a grayscale image, were generated. 1458 convolutional neural networks with...

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  • Improving the Survivability of Carrier Networks to Large-Scale Disasters

    Publikacja
    • A. de Sousa
    • J. Rak
    • F. Barbosa
    • D. Santos
    • D. Mehta

    - Rok 2020

    This chapter is dedicated to the description of methods aiming to improve the survivability of carrier networks to large-scale disasters. First, a disaster classification and associated risk analysis is described, and the disaster-aware submarine fibre-optic cable deployment is addressed aiming to minimize the expected costs in case of natural disasters. Then, the chapter addresses the improvement of the network connectivity resilience...

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  • Multi-task Video Enhancement for Dental Interventions

    A microcamera firmly attached to a dental handpiece allows dentists to continuously monitor the progress of conservative dental procedures. Video enhancement in video-assisted dental interventions alleviates low-light, noise, blur, and camera handshakes that collectively degrade visual comfort. To this end, we introduce a novel deep network for multi-task video enhancement that enables macro-visualization of dental scenes. In particular,...

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  • Topology recognition and leader election in colored networks

    Publikacja

    Topology recognition and leader election are fundamental tasks in distributed computing in networks. The first of them requires each node to find a labeled isomorphic copy of the network, while the result of the second one consists in a single node adopting the label 1 (leader), with all other nodes adopting the label 0 and learning a path to the leader. We consider both these problems in networks whose nodes are equipped with...

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  • Quality of service in optical burst switched networks

    In the paper analytical models of two service differentiation schemes for optical burst switched network: extended offset time based and PPS (Preemptive Priority Scheme) are revised. Also accordance of analytical models for those schemes is studied when complete class isolation is assumed. Furthermore authors introduce an analytical model which describes an effective degree of isolation when burst switched network employs both...

  • Quality of service in optical burst switched networks

    Publikacja

    In the paper analytical models of two service differentiation schemes for optical burst switched network: extended offset time based and PPS (Preemptive Priority Scheme) are revised. Also accordance of analytical models for those schemes is studied when complete class isolation is assumed. Furthermore authors introduce an analytical model which describes an effective degree of isolation when burst switched network employs both...

  • Multi-headed chimera states in coupled pendula

    Publikacja
    • P. Jaros
    • Ł. Borkowski
    • B. Witkowski
    • K. Czołczyński
    • T. Kapitaniak

    - The European Physical Journal-Special Topics - Rok 2015

    We discuss the occurrence of the chimera states in the network of coupled, excited by the clock’s mechanisms pendula. We find the patterns of multi-headed chimera states in which pendula clustered in different heads behave differently (oscillate with different frequencies) and create different types of synchronous states (complete or phase synchronization). The mathematical model of the network shows that the observed chimera states...

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  • TRAFFIC MODEL OF A MULTIDOMAIN IMS/NGN

    In this paper we continue our research and present an analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The model takes into account several service scenarios (including registration, intra- and inter-operator calls) and a large set of network parameters. Using the model mean Call Set-up Delay and mean Call...

  • Routing decisions independent of queuing delays in broadband leo networks

    Publikacja

    - Rok 2009

    This paper presents an analysis of queuing and propagation delays of Inter-Satellite Links (ISLs) in broadband Low-Earth Orbit (LEO) satellite networks. It is shown that queuing delays are negligible in all reasonable working conditions of the broadband ISL network. This fact makes it possible to simplify the routing protocols in such networks and permits using already known multi-commodity flow solutions for routing. The performance...

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  • Methodology of Conformity Testing of VoIP Connections Scenarios for SIP Protocol

    Conformity and conformity testing have always had a crucial role in telecommunications. These issues are especially important in VoIP technology with SIP protocol as there are many hardware, software and service implementations. In this paper a methodology of automatic conformity testing of VoIP connections scenarios applying to any IP network is proposed. Example implementation of the methodology as Linux shell scripts is presented....

  • Analysis of economical lighting of highways in the environment of SMOL language

    The paper puts forward and implements a method of designing and creating a modelling simulation environment for eztensive and complete analysis of economical lighting on highways. From a general design viewpoint, the proposed solution explores the concept of a network description language (SMOL), which has been designed to describe the necessary network functions, mechanisms, and devices; for the purpose of their computer simulation...

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  • Capacity analysis of the selected track system in partially ordered space

    A proper location of the interval sections has significant impact on the traffic flow in the railway track network. This issue is critical during line modernization as well as when a new solution accounting for the traffic forecast at particular element of the railway track network is developed . However, the situation is more complex and more expensive for railway stations since improvement of the capacity requires critical organizational...

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  • An advanced tool integrating failure and sensitivity analysis into novel modeling of the stormwater flood volume

    Publikacja

    - HYDROLOGY AND EARTH SYSTEM SCIENCES - Rok 2023

    An innovative tool for modeling the specific flood volume was presented that can be applied to assess the need for stormwater network modernization as well as for advanced flood risk assessment. Field measurements for a catchment area in Kielce, Poland, were used to apply the model and demonstrate its usefulness. This model extends the capability of recently developed statistical and machine learning hydrodynamic models developed...

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  • Gossiping by energy-constrained mobile agents in tree networks

    Publikacja

    - THEORETICAL COMPUTER SCIENCE - Rok 2021

    Every node of an edge-weighted tree network contains a data packet. At some nodes are placed mobile agents, each one possessing an amount of energy (not necessarily the same for all agents). While walking along the network, the agents spend the energy proportionally to the distance traveled and collect copies of the data packets present at the visited network nodes. An agent visiting a node deposits there copies of all currently...

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  • Massive Open Online Courses (MOOCs) in hospitality and tourism

    Publikacja
    • J. Murphy
    • N. Kalbaska
    • L. Cantoni
    • L. Horton-Tognazzini
    • P. Ryan
    • A. Williams

    - Rok 2018

    The tourism industry, interesting and challenging, faces structural human resource problems such as skills shortages and staff turnover, seasonality and a high percentage of small to medium enterprises whose employees have limited time for training or education. Large tourism enterprises often span countries and continents, such as hotel chains, airlines, cruise companies and car rentals, where the employees need similar training...

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  • Implementation of daylight design strategies in urban planning - barriers to application in Poland

    Publikacja

    - Rok 2015

    This paper reflects on studies done in the area of daylight design methods with regard to principles that can be applied in architecture and urban planning strategies. The paper addresses barriers to the application of new daylight design methods in urban planning, and in particular discusses current Polish building regulations in the context of daylight design. The results of the pilot study carried out among 82 participants show...

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  • Visual Features for Improving Endoscopic Bleeding Detection Using Convolutional Neural Networks

    Publikacja

    The presented paper investigates the problem of endoscopic bleeding detection in endoscopic videos in the form of a binary image classification task. A set of definitions of high-level visual features of endoscopic bleeding is introduced, which incorporates domain knowledge from the field. The high-level features are coupled with respective feature descriptors, enabling automatic capture of the features using image processing methods....

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  • Approximation of Message Inter-Arrival and Inter-Departure Time Distributions in IMS/NGN Architecture Using Phase-Type Distributions

    Currently it is assumed that requirements of the information society for delivering multimedia services will be satisfied by the Next Generation Network (NGN) architecture, which includes elements of the IP Multimedia Subsystem (IMS) solution. In order to guarantee Quality of Service (QoS), NGN has to be appropriately designed and dimensioned. Therefore, proper traffic models should be proposed and applied. This requires determination...

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  • Simulation model for evaluation of QoS routing algorithm in large packet networks

    The variety of traffic transferred via current telecommunication networks includes also voice, which should meet quality requirements. One of mechanisms, which can support QoS in current packet networks, is routing. There exist many routing proposals which should introduce the QoS into the network but practically they don't. Following paper presents the realization of simulation model for evaluation of a new routing algorithm DUMBRA...

  • Potential and Use of the Googlenet Ann for the Purposes of Inland Water Ships Classification

    Publikacja

    - Polish Maritime Research - Rok 2020

    This article presents an analysis of the possibilities of using the pre-degraded GoogLeNet artificial neural network to classify inland vessels. Inland water authorities monitor the intensity of the vessels via CCTV. Such classification seems to be an improvement in their statutory tasks. The automatic classification of the inland vessels from video recording is a one of the main objectives of the Automatic Ship Recognition and...

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  • Technological solutions to landfill management: Towards recovery of biomethane and carbon neutrality

    Publikacja

    - JOURNAL OF ENVIRONMENTAL MANAGEMENT - Rok 2024

    Inadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change,...

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  • Kobiety i mezczyźni w zespole - wartość czy wyzwanie

    Artykuł dotyczy zarządzania zespołami zróżnicowanymi pod względem płci. Zaprezentowano wyniki badań przeprowadzonych wśród słuchaczy podyplomowych studiów Zarządzania Zasobami Ludzkimi. Celem badań była weryfikacja sposobu postrzegania zespołów zróżnicowanych pod względem płci przez osoby związane z zarządzaniem kapitałem ludzkim. Dodatkowo oceniono poziom wykorzystywania wartości takich zespołów w firmach reprezentowanych przez...

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  • Event driven MPC for networked control systems

    Publikacja

    - Rok 2008

    Because of variable delays and stochastic data packets loss networked control systems require suitable algorithms to ensure stability of the control system and guarantee desired control performance. This paper presents the idea of an event driven approach with MPC controller. In opposition to network compensation, where standard regulators are used, the presented solution integrates network with plant. A MPC based controller is...

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  • Detecting type of hearing loss with different AI classification methods: a performance review

    Publikacja
    • M. Kassjański
    • M. Kulawiak
    • T. Przewoźny
    • D. Tretiakow
    • J. Kuryłowicz
    • A. Molisz
    • K. Koźmiński
    • A. Kwaśniewska
    • P. Mierzwińska-Dolny
    • M. Grono

    - Rok 2023

    Hearing is one of the most crucial senses for all humans. It allows people to hear and connect with the environment, the people they can meet and the knowledge they need to live their lives to the fullest. Hearing loss can have a detrimental impact on a person's quality of life in a variety of ways, ranging from fewer educational and job opportunities due to impaired communication to social withdrawal in severe situations. Early...

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  • Long-distance quantum communication over noisy networks without long-time quantum memory

    Publikacja
    • P. Mazurek
    • A. Grudka
    • M. Horodecki
    • P. Horodecki
    • J. Łodyga
    • Ł. Pankowski
    • A. Przysiężna

    - PHYSICAL REVIEW A - Rok 2014

    The problem of sharing entanglement over large distances is crucial for implementations of quantum cryptography. A possible scheme for long-distance entanglement sharing and quantum communication exploits networks whose nodes share Einstein-Podolsky-Rosen (EPR) pairs. In Perseguers et al. [Phys. Rev. A 78, 062324 (2008)] the authors put forward an important isomorphism between storing quantum information in a dimension D and transmission...

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  • Soft Real-Time Communication with WebSocket and WebRTC Protocols Performance Analysis for Web-based Control Loops

    Publikacja

    - Rok 2019

    The web browser has become an access window for content and services. The browser is available on almost any device connected to the network, regardless of its intended use: desktop, mobile device, computing server, e-book reader etc. Browsers are used by people to read news, contact the world, to check a bank account, register a visit at the doctor, watching video content, electronic purchases, using web versions of the office...

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  • Application of wavelength division multiplexing in sensor networks

    Publikacja

    - Rok 2012

    Over the past few years the need to acquire data on various parameters from a number of sensors grew. The need that led to the development of a network of sensors which enables simultaneous control and measurement in a wide range of applications. The aim of this article is to discuss a possibility of connecting a variety of sensors in a network that would utilize WDM technology. Wavelength Division Multiplexing is commonly used...

  • The Use of an Autoencoder in the Problem of Shepherding

    Publikacja

    This paper refers to the problem of shepherding clusters of passive agents consisting of a large number of objects by a team of active agents. The problem of shepherding and the difficulties that arise with the increasing number of data describing the location of agents have been described. Several methods for reducing the dimensionality of data are presented. Selected autoencoding method using a Restricted Boltzmann Machine is...

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  • Understanding the Relation between HR Practices and Pull Approach to Knowledge Sharing: Case Study

    Publikacja

    The aim of this study is to identify the relationship between human resource (HR) practices, knowledge seeking and knowledge giving by applying the lenses of the motivation-opportunities-abilities framework in the context of the multinational enterprise subsidiary located in Central Europe. The article presents the research results using qualitative methodology, mainly based on semi-structured interviews among employees of a...

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  • Challenges and future prospectives of MXenes

    Publikacja
    • A. Akhlaq
    • S. Latif
    • M. Imran
    • A. Javaid
    • G. Boczkaj

    - Rok 2024

    In the context of nanotechnology, MXenes gained considerable attention as two-dimensional (2D) materials derived from layered transition metal carbides, nitrides, and carbonitrides. These materials display distinct characteristics with promising implications for a variety of practical applications. This book chapter provides an extensive exploration into MXenes’ fundamental concepts, such as how they are classified based on various...

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  • ICT-enabled circular economy: conceptualising the links

    Publikacja

    This chapter sets conceptual backgrounds regarding the potentially emerging causal links between digital technologies and circular economy ideas implementation. We argue that digital technologies may constitute an effective element enabling the transformation from linear to circular and environmentally friendly economic activities. This work draws the general picture at the macro and micro level. The macro perspective shows how...

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  • Energy Efficiency Study of Audio-video Content Consumption on Selected Android Mobile Terminals

    Publikacja

    Mobile devices are widely used by billions of users worldwide. Thanks to their main advantage, which is portability, they should be fully operational as long as possible, without the need to recharge or connect them to external power sources. This paper describes a study, carried out on four different mobile devices, with different hardware and software parameters, running the Android operating system. The research campaign involved...

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  • A standard analytical method as the common good and pollution abatement measure

    A standard method can be considered as a common-good “resource,” and the solution to “the commons” problems usually lies in societal self-organization. The multi-criteria decision analysis (MCDA) was applied to model complex phenomena, such as the standard selection for imidacloprid determination. In this process, the standard was self-selected by the analytical chemistry society. The results show that analytical chemistry is a...

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  • Fake VIP Attacks and Their Mitigation via Double-Blind Reputation

    Publikacja

    - Rok 2017

    In a generic setting subsuming communication networks, resource sharing systems, and multi-agent communities, a client generates objects of various classes carrying class-dependent signatures, to which a server assigns class-dependent service quality. A Fake VIP attack consists in false declaration of a high class, with an awareness that detection of object signature at the server side is costly and so invoked reluctantly. We show...

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  • Perspectives of Transport Systems Development in the Light of Radio Communication Systems Evolution Towards 5G

    Publikacja

    - Rok 2017

    In the paper conditions of development and implementation of transport systems with reference to the development of radio communication networks towards 5G are presented. First, general properties of next generation systems are mentioned and their architecture. Moreover, planned characteristics of B4G and 5G systems are depicted which can significantly contribute to the promotion and development of transport systems. In particular...

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