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Number of results: 310
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Abstract

Cross layer cooperative protocol which exploits the benefits of physical layer cooperative communication, is one of the widely recognized MAC layer protocol design strategies for future wireless networks. This paper presents performance analysis of a cooperative mac and these performance parameters are compared those of the legacy IEEE 802.11 DCF MAC. Appropriate relay station selection is the main hurdle in designing efficient cooperative MAC protocol for wireless networks. This cooperative mac demonstrated that intermediate relay nodes themselves can initiate cooperation for relaying data frame to the receiver on behalf of the sender. This procedure makes the selection process of a “helper node” more distributed in nature as well as it contributes to increase throughput of a wireless network by reducing the overheads that are usually incurred in the helper selection process. It has been shown by thorough analytical analysis that the proposed cooperative MAC protocol offers higher throughput and lower frame transmission delay in both ideal and error prone wireless environment. These performance metrics are also evaluated while the wireless nodes are mobile as well.

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Authors and Affiliations

Md. Ruhul Amin
Md. Shohrab Hossain
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Abstract

The article refers to the idea of using the software defined network (SDN) as an effective hardware and software platform enabling the creation and dynamic management of distributed ICT infrastructure supporting the rapid prototyping process. The authors proposed a new layered reference model remote distributed rapid prototyping that allows the development of heterogeneous, open systems of rapid prototyping in a distributed environment. Next, the implementation of this model was presented in which the functioning of the bottom layers of the model is based on the SDN architecture. Laboratory tests were carried out for this implementation which allowed to verify the proposed model in the real environment, as well as determine its potential and possibilities for further development. Thus, the approach described in the paper may contribute to the development and improvement of the efficiency of rapid prototyping processes which individual components are located in remote industrial, research and development units. Thanks to this, it will be possible to better integrate production processes as well as optimize the costs associated with prototyping. The proposed solution is also a response in this regard to the needs of industry 4.0 in the area of creating scalable, controllable and reliable platforms.

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Authors and Affiliations

D. Mazur
A. Paszkiewicz
M. Bolanowski
G. Budzik
M. Oleksy
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Abstract

The paper presents the concept of vital cities in the context of mechanisms of sustainable development, networking and creativity. The vital city was presented as:

- a city belonging to the inhabitants – a city managed and developed with advanced processes of participation,

- a city of reasonable management – a city that uses and at the same time protects its key potentials,

- a city of creation – a city of creating and implementing new ideas,

- a city of opportunities – a city that creates the conditions for the use of energy and creativity residents,

- a city in the surround – a city with a strong position in the environment.

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Authors and Affiliations

Krzysztof Wrana
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Abstract

This paper presents a new OpenFlow controller: the Distributed Active Information Model (DAIM). The DAIM controller was developed to explore the viability of a logically distributed control plane. It is implemented in a distributed way throughout a software-defined network, at the level of the switches. The method enables local process flows, by way of local packet switching, to be controlled by the distributed DAIM controller (as opposed to a centralised OpenFlow controller). The DAIM ecosystem is discussed with some sample code, together with flowcharts of the implemented algorithms. We present implementation details, a testing methodology, and an experimental evaluation. A performance analysis was conducted using the Cbench open benchmarking tool. Comparisons were drawn with respect to throughput and latency. It is concluded that the DAIM controller can handle a high throughput, while keeping the latency relatively low. We believe the results to date are potentially very interesting, especially in light of the fact that a key feature of the DAIM controller is that it is designed to enable the future development of autonomous local flow process and management strategies.
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Authors and Affiliations

Pupatwibul Pakawat
Banjar Ameen
Hossain Md. Imam
Robin Braun
Bruce Moulton
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Abstract

Recent research has shown that the increase in a number of participants of construction project elevated the cost and duration of construction. The use of integrated project delivery and the formation of a network organization structure can significantly reduce the costs, as the activities of the participants become more coherent and coordinated. The optimization of decisions is essential for the efficiency of a negotiation process, which in turn depends on the organizational structure. The article specifies three basic types of network organizational structure that can be applied in a construction project: focal (F1), dynamic (F2), multifocal (F3). In this study, a direct assessment of possible effectiveness of each of the three types of network organizational structures was carried out using a vector decision model. For each of the above-mentioned types of organizational structures, the potential effectiveness of negotiating act f0 and the total potential effectiveness F0 was calculated. The results of the study show that the most effective type of network organizational structure is the multifocal collective decisions in which a project manager has several “assistants”.
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Authors and Affiliations

Roman Trach
1
ORCID: ORCID
Mieczysław Połoński
2
ORCID: ORCID
Petro Hrytsiuk
3
ORCID: ORCID

  1. PhD., Warsaw University of Life Sciences-SGGW, Institute of Civil Engineering, ul. Nowoursynowska 159, 02-776 Warsaw, Poland
  2. Prof. PhD. Eng., Warsaw University of Life Sciences-SGGW, Institute of Civil Engineering, Nowoursynowska 159,02-776 Warsaw, Poland
  3. Prof. PhD., National University of Water and Environmental Engineering, Soborna 11, 33028 Rivne, Ukraine
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Abstract

The results of analysis of geometrical structure of modular networks are discussd in the paper. The criteria of technical correctness of such construction were determined. The algebraic relationship between the network components, e.g. station number, tie points, number of measurements, was analysed. The determination conditions for a single module and for a surface network have been introduced considering the existence of elementary modules that are not internally determined. A comparative test for modular and classical models of network was performed using a computer program. The results illustrate positioning accuracy achievable with use of modular networks. The conclusions presented might be helpful when designing surveying networks.
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Authors and Affiliations

Tadeusz Gargula
ORCID: ORCID
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Abstract

The paper presents the possibilities of neural network application in recognition of rotor blade faults. Computer calculated data of rotor response due to faults were used for neural network training. The rotor was modeled by elastic axes with distribution of Jumped masses. The rotor defects were simulated by changing aerodynamic, inertial or stiffness properties of one of the blades. Time results were subjected to spectral analysis for the purpose of neural networks training.
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Authors and Affiliations

Jarosław Stanisławski
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Abstract

The study presents results of the internal reliability analysis of structural modules used for the determination of horizontal displacement in incomplete trigonometric network. The influence of such elements as: number of control points, sight line length and arrangement of control points around the instrument station on reliability was analysed. Furthermore the analysis of the influence of diversification of reliability indices calculated for individual observations on the detection efficiency of non-dislocated control points was performed. The presented numerical example illustrates the possibility of incorrect valuation of control point stability because of a large diversification of reliability indices. The summary contains recommendations from the point of view of internal reliability for optimal designing of structural modules in incomplete trigonometric networks.
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Authors and Affiliations

Mieczysław Kwaśniak
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Abstract

An information security audit method (ISA) for a distributed computer network (DCN) of an informatization object (OBI) has been developed. Proposed method is based on the ISA procedures automation by using Bayesian networks (BN) and artificial neural networks (ANN) to assess the risks. It was shown that such a combination of BN and ANN makes it possible to quickly determine the actual risks for OBI information security (IS). At the same time, data from sensors of various hardware and software information security means (ISM) in the OBI DCS segments are used as the initial information. It was shown that the automation of ISA procedures based on the use of BN and ANN allows the DCN IS administrator to respond dynamically to threats in a real time manner, to promptly select effective countermeasures to protect the DCS.
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Authors and Affiliations

Berik Akhmetov
1
Valerii Lakhno
2
Vitalyi Chubaievskyi
3
Serhii Kaminskyi
3
Saltanat Adilzhanova
4
Moldir Ydyryshbayeva
4

  1. Yessenov University, Aktau, Kazakhstan
  2. National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
  3. Kyiv National University of Trade and Economics, Kyiv, Ukraine
  4. Al-Farabi Kazakh National University, Almaty, Kazakhstan
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Abstract

The paper focuses on the optimization of IEEE 802.11ax dense networks. The results were obtained with the use of the NS-3 simulator. Various network topologies were analyzed and compared. The advantage of using MSDU and MPDU aggregations in a dense network environment was shown. The process of improving the network performance for changes in the transmitter power value, CCA Threshold, and antenna gain was presented. The positive influence of BSS coloring mechanism on overal network efficiency was revealed. The influence of receiver sensitivity on network performance was determined.
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Authors and Affiliations

Marek Natkaniec
1
Mateusz Kras
2

  1. Faculty of Computer Science, Electronics and Telecommunications, Institute of Telecommunications, AGH University of Science and Technology, Poland
  2. AGH University of Science and Technology, Poland
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Abstract

A mathematical model is proposed that makes it possible to describe in a conceptual and functional aspect the formation and application of a knowledge base (KB) for an intelligent information system (IIS). This IIS is developed to assess the financial condition (FC) of the company. Moreover, for circumstances related to the identification of individual weakly structured factors (signs). The proposed model makes it possible to increase the understanding of the analyzed economic processes related to the company's financial system. An iterative algorithm for IIS has been developed that implements a model of cognitive modeling. The scientific novelty of the proposed approach lies in the fact that, unlike existing solutions, it is possible to adjust the structure of the algorithm depending on the characteristics of a particular company, as well as form the information basis for the process of assessing the company's FC and the parameters of the cognitive model.
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Authors and Affiliations

Olena Kryvoruchko
1
Alona Desiatko
1
Igor Karpunin
1
Dmytro Hnatchenko
1
Myroslav Lakhno
2
Feruza Malikova
3
Ayezhan Turdaliev
4

  1. State University of Trade and Economics, Kyiv, Ukraine
  2. National University of Life and EnvironmentalSciences of Ukraine, Kyiv
  3. Almaty Technological University, Almaty,Kazakhstan
  4. Kazakh University of Railways andTransportation, Almaty, Kazakhstan
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Abstract

The recent decades have seen the growth in the fields of wireless communication technologies, which has made it possible to produce components with a rational cost of a few cubic millimeters of volume, called sensors. The collaboration of many of these wireless sensors with a basic base station gives birth to a network of wireless sensors. The latter faces numerous problems related to application requirements and the inadequate abilities of sensor nodes, particularly in terms of energy. In order to integrate the different models describing the characteristics of the nodes of a WSN, this paper presents the topological organization strategies to structure its communication. For large networks, partitioning into sub-networks (clusters) is a technique used to reduce consumption, improve network stability and facilitate scalability.
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Authors and Affiliations

Sarang Dagajirao Patil
1
Pravin Sahebrao Patil
2

  1. NES Gangamai College of Engineering, Nagaon, Dhule, Maharashta, India
  2. Dept. of E&C Engineering SSVPSBSD College of Engineering Dhule, Maharashtra, India
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Abstract

A spectrum defragmentation problem in elastic optical networks was considered under the assumption that all connections can be realized in switching nodes. But this assumption is true only when the switching fabric has appropriate combinatorial properties. In this paper, we consider a defragmentation problem in one architecture of wavelength-spacewavelength switching fabrics. First, we discuss the requirements for this switching fabric, below which defragmentation does not always end with success. Then, we propose defragmentation algorithms and evaluate them by simulation. The results show that proposed algorithms can increase the number of connections realized in the switching fabric and reduce the loss probability.

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Authors and Affiliations

Remigiusz Rajewski
Wojciech Kabaciński
Atyaf Al-Tameemi
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Abstract

This paper proposes three methods of the optimal smart meter selection for acting as a data concentrator in the automatic meter reading last mile network. The study explains the reasons why the selected smart meter should also act as a data concentrator, in addition to its basic role. To select the smart meter, either the reliability of communication or the speed of the automatic meter reading process was considered. Graph theory is employed to analyse the last mile network, described as sets of nodes and unreliable links. The frame error ratio was used to assess the unreliability whilst the number of hops was used to describe the speed of the reading process. The input data for the analysis are qualitative parameters determined based on observations in the real, operated last mile networks as well as their typical topological arrangements. The results of the research can be useful in the last mile network migration process, which uses concentrators to the networks without them, or during the process of newer last mile network implementation, where data concentrators are no longer applicable. The efficiency of the proposed methods is assessed measurably.
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Authors and Affiliations

Piotr Kiedrowski
1
ORCID: ORCID

  1. Institute of Telecommunications and Computer Science, Bydgoszcz University of Science and Technology,Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland
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Abstract

Extensive use of computer networks is associated with the development of various effective methods that are suitable for hiding information in the contents transferred over the network. These methods are described as network steganography. Since web applications use HTTP protocol to transmit the requests to the server and send the answers to the final recipient, specifically HTTP protocol is ideal for hiding information. For example, there are several methods that can be used to transmit the additional content in the HTTP header. In this paper, we present authors’ evaluation method for network steganography using HTTP specific properties and evaluate the effectiveness of some techniques, providing experimental results.

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Authors and Affiliations

Paweł Buchwald
Maciej Rostański
Krystian Mączka
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Abstract

Artificial neural networks are gaining popularity thank to their fast and accurate response paired with low computing power requirements. They have been proven as a method for compressor performance prediction with satisfactory results. In this paper a new approach of artificial neural networks modelling is evaluated. The auxiliary parameter of ‘relative stability margin Z’ was introduced and used in learning process. This approach connects two methods of compressor modelling such as neuralnetworks and auxiliary parameter utilization. Two models were created, one with utilization of the ‘relative stability margin Z’ as a direct indication of surge margin of any estimated condition, and other with standard compressor parameters. The results were compared by determination of fitting, interpolation and extrapolation capabilities of both approaches. The artificial neural networks used during the process was a two-layer feed-forward neural-network with Levenberg–Marquardt algorithm with Bayesian regularization. The experimental data was interpolated to increase the amount of learning data for the neural network. With the two models created, capabilities of this relatively simple type of neural-network to approximate compressor map was also assessed.
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Bibliography

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Authors and Affiliations

Sergiusz Michał Loryś
1
Marek Orkisz
2

  1. Hamilton Sundstrand Poland / Pratt & Whitney AeroPower Rzeszów, Hetmanska 120, 35-078 Rzeszów, Poland
  2. Rzeszow University of Technology, Department of Aerospace Engineering, Powstanców Warszawy 8, 35-959 Rzeszów, Poland
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Abstract

The rapid development of the Internet of Things (IoT) and the wide area of application rise the IoT concept to be the future of the internet. Indeed, IoT environment has a special nature with a lot of constraints in term of resource consumption. Moreover, the data exchanged between things and the internet is big data. In order to achieve efficiency in IoT communication, many technologies and new protocols based on these technologies have been developed. This paper aims to study the performance of Message Queuing Telemetry Transport (MQTT) by implementing this protocol on test-bed network infrastructure and analyzing the performance properties such as delay, jitter, packet loss and throughput for real time and non-real time scenarios. Finally, future research issues in MQTT protocol are suggested.
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Bibliography

[1] I. T. S. Sector, Recommendation ITU-T Y. 2060, “Overview of the Internet of things. Series Y: Global information infrastructure, internet protocol aspects and next-generation networks-Frameworks and functional architecture models,” 2012. Retrieved from https://www. itu. int/rec/T-REC-Y, 2060-201206.
[2] D. Bandyopadhyay, and J. Sen, “Internet of Things: Applications and Challenges in Technology and Standardization,” Wireless Pers Commun, vol. 58(1), pp. 49-69, 2011. http://dx.doi.org/10.1007/s11277-011-0288-5
[3] MQTT Version 5.0. Edited by Andrew Banks, Ed Briggs, Ken Borgendale, and Rahul Gupta. 07 March 2019. OASIS Standard. https://docs.oasis-open.org/mqtt/mqtt/v5.0/os/mqtt-v5.0-os.html.
[4] Postscapes.com, Internet of Things Examples – Postscapes, 2020. Retrieved 20 April 2020, from http://postscapes.com/internet-of-things-examples/
[5] S. Schneider, Understanding The Protocols Behind The Internet Of Things. Electronicdesign.com, 2013. Retrieved 20 April 2020, from http://electronicdesign.com/iot/understanding-protocols-behind-internet-things
[6] C. Karasiewicz, Why HTTP is not enough for the Internet of Things (The Mobile Frontier). Ibm.com, 2013. Retrieved 20 April 2020, from https://www.ibm.com/developerworks/community/blogs/mobileblog/date/201309?lang=en
[7] IoT Analytics - Market Insights for the Internet Of Things, The 10 most popular Internet of Things applications right now, 2015. Retrieved 20 April 2020, from http://iot-analytics.com/10-internet-of-things-applications/
[8] Mqtt.org, FAQ - Frequently Asked Questions | MQTT, 2020. Retrieved 20 April 2020, from http://mqtt.org/faq
[9] U. Hunkeler, H. L. Truong, and A. Stanford-Clark, “MQTT-S—A publish/subscribe protocol for Wireless Sensor Networks,” In 2008 3rd International Conference on Communication Systems Software and Middleware and Workshops (COMSWARE'08), Jan. 2008, pp. 791-798, IEEE. https://doi.org/10.1109/COMSWA.2008.4554519
[10] R. Webb, A Brief, but Practical Introduction to the MQTT Protocol and its Application to IoT | Zoetrope, 2016. Retrieved 20 April 2020, from https://zoetrope.io/tech-blog/brief-practical-introduction-mqtt-protocol-and-its-application-iot

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Authors and Affiliations

Ghofran Hijazi
1
Mohamed Hadi Habaebi
1
Ahmed Al-Haddad
1
Alhareth Mohammed Zyoud
2

  1. Department of Electrical and Computer Engineering, Faculty of Engineering, International Islamic University Malaysia, Kuala Lumpur, Malaysia
  2. Department of Electrical and Computer Engineering, Faculty of Engineering and Technology, Birzeit University, Birzeit, Ramallah, Palestine
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Abstract

Single Frequency Networks (SFN) of transmitters are currently used in television and digital broadcasting to effectively cover large areas using minimal spectral resources and using transmitters with much lower power than if the same area were covered using one transmitter. It is therefore a very ecological solution. In this way, much better reception conditions are obtained in large city areas, as the signal reaches the receiving antenna from different directions, reducing the risk of shading. However, in this type of network one should take into account the loss of signal caused by signal interference. Using the appropriate propagation model, it is possible, with appropriate assumptions, to check how the operation of the third transmitter affects the distribution and size of the deepest fades in relation to the network in which there are two transmitters.

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Authors and Affiliations

Ryszard J. Z Ziielinski
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Abstract

A novel algorithm is presented to deduce individual nodal forwarding behavior from standard end-to-end acknowledgments. The algorithm is based on a well-established mathematical method and is robust to network related errors and nodal behavior changes. The proposed solution was verified in a network simulation, during which it achieved sound results in a challenging multihop ad-hoc network environment.

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Authors and Affiliations

Karol Rydzewski
Jerzy Konorski
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Abstract

Packet-switched xHaul networks are a scalable solution enabling convergent transport of diverse types of radio data flows, such as fronthaul / midhaul / backhaul (FH / MH / BH) flows, between remote sites and a central site (hub) in 5G radio access networks (RANs). Such networks can be realized using the cost-efficient Ethernet technology, which enhanced with time-sensitive networking (TSN) features allows for prioritized transmission of latency-sensitive fronthaul flows. Provisioning of multiple types of 5G services of different service requirements in a shared network, commonly referred to as network slicing, requires adequate handling of transported data flows in order to satisfy particular service / slice requirements. In this work, we investigate two traffic prioritization policies, namely, flowaware (FA) and latency-aware (LA), in a packet-switched xHaul network supporting slices of different latency requirements. We evaluate the effectiveness of the policies in a networkplanning case study, where virtualized radio processing resources allocated at the processing pool (PP) facilities, for two slices related to enhanced mobile broadband (eMBB) and ultra-reliable low latency communications (URLLC) services, are subject to optimization. Using numerical experiments, we analyze PP cost savings from applying the LA policy (vs. FA) in various network scenarios. The savings in active PPs reach up to 40% − 60% in ring scenarios and 30% in a mesh network, whereas the gains in overall PP cost are up to 20% for the cost values assumed in the analysis.
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Authors and Affiliations

Mirosław Klinkowski
1

  1. National Institute of Telecommunications, Warsaw, Poland
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Abstract

This paper details a hardware implementation of a distributed Θ(1) time algorithm allows to select dynamically the master device in ad-hoc or cluster-based networks in a constant time regardless the number of devices in the same cluster. The algorithm allows each device to automatically detect its own status; master or slave; based on identifier without adding extra overheads or exchanging packets that slow down the network. We propose a baseband design that implements algorithm functions and we detail the hardware implementation using Matlab/Simulink and Ettus B210 USRP. Tests held in laboratory prove that algorithm works as expected.

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Authors and Affiliations

Mohammed El Khattabi
Jelloul Elmesbahi
Ahmed Errami and Omar Bouattane Mohammed Khaldoun
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Abstract

To better extract feature maps from low-resolution (LR) images and recover high-frequency information in the high-resolution (HR) images in image super-resolution (SR), we propose in this paper a new SR algorithm based on a deep convolutional neural network (CNN). The network structure is composed of the feature extraction part and the reconstruction part. The extraction network extracts the feature maps of LR images and uses the sub-pixel convolutional neural network as the up-sampling operator. Skip connection, densely connected neural networks and feature map fusion are used to extract information from hierarchical feature maps at the end of the network, which can effectively reduce the dimension of the feature maps. In the reconstruction network, we add a 3×3 convolution layer based on the original sub-pixel convolution layer, which can allow the reconstruction network to have better nonlinear mapping ability. The experiments show that the algorithm results in a significant improvement in PSNR, SSIM, and human visual effects as compared with some state-of-the-art algorithms based on deep learning.
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Authors and Affiliations

Xin Yang
1
Yifan Zhang
1
Dake Zhou
1

  1. College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, 210016 Nanjing, Jiangsu, China
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Abstract

Human brain is “the perfect guessing machine” (James V. Stone (2012) Vision and Brain, Cambridge, Mass: The MIT Press, p. 155), trying to interpret sensory data in the light of previous biases or beliefs. Bayesian inference is carried out by three complex networks of the human brain: salience network, central executive network, and default mode network. Their function is analysed both in neurotypical person and Attention Deficit Disorder. Modern human being having predictive brain and overloaded mind must develop social identity, whose evolution went probably through three stages: social selection based on punishment, sexual selection based on reputation, and group selection based on identity.

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Authors and Affiliations

Maciej Błaszak
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Abstract

The aim of the presented paper was to verify the impact of Dynamic PUCCH Resource Allocation Algorithm of the LTE cellular system on the maximum uplink cell throughput and call setup success rate-CSSR. Paper includes the laboratorytestbeddescription and presents the results of an experiment confirming the improvement of both key performance indicatorsKPIs.Apart from the presentation of the Dynamic PUCCH Resource allocation algorithm, the paper also includes a description of legacy LTE uplink (PUCCH and PUSCH) channels dimensioning process thus filling the gap of such a tutorial in the available literature.

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Authors and Affiliations

Maciej Czerniecki
Jacek Wszołek
Marek Sikora
ORCID: ORCID
Wiesław Ludwin

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