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Number of results: 401
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Abstract

Artificial neural network (ANN), a Computational tool that is frequently applied in the modeling and simulation of manufacturing processes. The emerging forming technique of sheet metal which is typically called single point incremental forming (SPIF) comes into the map and the research interest towards its technological parameters. The surface quality of the end product is a major issue in SPIF, which is more critical with the hard metals. The part of the brass metal is demanded in many industrial uses because of its high load-carrying capacity and its wear resistance property. Considering the industrial interest and demand of the brass metal products, the present study is done with the SPIF experiment on calamine brass Cu67Zn33 followed by an ANN analysis for predicting the absolute surface roughness. The modeling result shows a close agreement with the measured data. The minimum and maximum errors are found in experiment 3 and experiment 7 respectively. The error of predicted roughness is found in the range of –30.87 to 20.23 and the overall coefficient of performance of ANN modeling is 0.947 which is quite acceptable.
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Authors and Affiliations

Manish Oraon
1
Vinay Sharma
1

  1. Birla Institute of Technology, Faculty of Production Engineering, India
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Abstract

In this work, the level of influence of the posts published by famous people on social networks on the formation of the cryptocurrency exchange rate is investigated. Celebrities who are familiar with the financial industry, especially with the cryptocurrency market, or are somehow connected to a certain cryptocurrency, such as Elon Musk with Dogecoin, are chosen as experts whose influence through social media posts on cryptocurrency rates is examined. This research is conducted based on statistical analysis. Real cryptocurrency exchange rate forecasts for the selected time period and predicted ones for the same period, obtained using three algorithms, are utilized as a dataset. This paper uses methods such as statistical hypotheses regarding the significance of Spearman’s rank correlation coefficient and Pearson’s correlation. It is confirmed that the posts by famous people on social networks significantly affect the exchange rates of cryptocurrencies.
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Authors and Affiliations

Sergii Telenyk
ORCID: ORCID
Grzegorz Nowakowski
ORCID: ORCID
Olena Gavrilenko
Mykhailo Miahkyi
Olena Khalus
ORCID: ORCID
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Abstract

Transportation networks respond differently to applied policies. The Tehran Metropolitan Area has one of the most complex networks with complex users, which has experienced many of these policies change within the past decades. In this study, some of these policies and their effect on air pollution is investigated. The goal is to pinpoint the variables which have the most effect on various transportation models and investigate how new policies should be focused. In order to do so, long-term variations of air pollution monitoring stations were analyzed. Results show that the most significant parameter that may affect air pollution is users' behavior due to the lack of a public transportation network and its level of comfort. The results of this study will be useful in developing new policies and evaluating their long-term consequences in appropriate models.

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Authors and Affiliations

Mansour Hadji Hosseinlou
Shahab Kabiri
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Abstract

The aim of this study is to find the cost design of RC tension with varying conditions using the Artificial Neural Network. Design constraints were used to cover all reliable design parameters, such as limiting cross sectional dimensions and; their reinforcement ratio and even the beahviour of optimally designed sections. The design of the RC tension members were made using Indian and European standard specifications which were discussed. The designed tension members according to both codes satisfy the strength and serviceability criteria. While no literature is available on the optimal design of RC tension members, the cross-sectional dimensions of the tension membersfor different grades of concrete and steel, and area of formwork are considered as the variables in the present optimum design model. A design example is explained and the results are presented. It is concluded that the proposed optimum design model yields rational, reliable, and practical designs.

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Authors and Affiliations

N. Karthiga Shenbagam
N. Arunachalam
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Abstract

One of the basic parameters which describes road traffic is Annual Average Daily Traffic (AADT). Its accurate determination is possible only on the basis of data from the continuous measurement of traffic. However, such data for most road sections is unavailable, so AADT must be determined on the basis of short periods of random measurements. This article presents different methods of estimating AADT on the basis of daily traffic (VOL), and includes the traditional Factor Approach, developed Regression Models and Artificial Neural Network models. As explanatory variables, quantitative variables (VOL and the share of heavy vehicles) as well as qualitative variables (day of the week, month, level of AADT, the cross-section, road class, nature of the area, spatial linking, region of Poland and the nature of traffic patterns) were used. Based on comparisons of the presented methods, the Factor Approach was identified as the most useful.

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Authors and Affiliations

M. Spławińska
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Abstract

We propose the time slot routing, a novel routing scheme that allows for a simple design of interconnection networks. The simulative results show that the proposed scheme demonstrates optimal performance at the maximal uniform network load, and for uniform loads the network throughput is greater than for deflection routing.
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Authors and Affiliations

Ireneusz Szcześniak
Roman Wyrzykowski
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Abstract

Journal bearings are the most common type of bearings in which a shaft freely rotates in a metallic sleeve. They find a lot of applications in industry, especially where extremely high loads are involved. Proper analysis of the various bearing faults and predicting the modes of failure beforehand are essential to increase the working life of the bearing. In the current study, the vibration data of a journal bearing in the healthy condition and in five different fault conditions are collected. A feature extraction method is employed to classify the different fault conditions. Automatic fault classification is performed using artificial neural networks (ANN). As the probability of a correct prediction goes down for a higher number of faults in ANN, the method is made more robust by incorporating deep neural networks (DNN) with the help of autoencoders. Training was done using the scaled conjugate gradient algorithm and the performance was calculated by the cross entropy method. Due to the increased number of hidden layers in DNN, it is possible to achieve a high efficiency of 100% with the feature extraction method.

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Authors and Affiliations

T. Narendiranath Babu
Arun Aravind
Abhishek Rakesh
Mohamed Jahzan
D. Rama Prabha
Mangalaraja Ramalinga Viswanathan
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Abstract

The paradox of enterprise management is the company must continually change in a dynamic and difficult-to-predict environment in order to achieve business continuity and profitability goals. The relatively low efficiency and awareness of the need for change at network organizations means the problems connecting with changes implementation, identification of conditions limiting their realizations and importance of final results are still significant. This article described this issue by the diagnosis of current state of the change management in various types of network organizations and showing how this state can be improved in the future. Assuming the organization will strive for conscious and organized change management.
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Authors and Affiliations

Katarzyna Rostek
Daniel Młodzianowski
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Abstract

The 802.11ax standard final specification is expected in 2019, however first parameters are just released. The target of the new standard is four times improvement of the average throughput within the given area. This standard is dedicated for usage in dense environment such as stadiums, means of municipal communication, conference halls and others. The main target is to support many users at the same time with the single access point. The question arises if the new standard will have higher throughput then previous ones in the single user mode. The author calculated the maximal theoretical throughput of the 802.11ax standard and compared the results with the throughput of older 802.11 standards such as 802.11n and 802.11ac. The new he-wifi-network example included in the ns-3.27 release of the NS-3 simulator was used to simulate the throughput between the access point and the user terminal. The results indicate that in some conditions the 802.11ac standard has higher throughput than the new 802.11ax standard.

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Authors and Affiliations

Antoni Masiukiewicz
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Abstract

In the article we study a model of TCP connection with Active Queue Managementin an intermediate IP router. We use the fluid flow approximation technique to model the interactions between the set of TCP flows and AQM algoithms. Computations for fluid flow approximation model are performed in the CUDA environment.
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Authors and Affiliations

Adam Domański
Joanna Domańska
Tadeusz Czachórski
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Abstract

In the article we study a model of network transmissions with Active Queue Management in an intermediate IP router. We use the OMNET++ discrete event simulator to model the varies variants of the CHOKe algoithms. We model a system where CHOKe, xCHOKe and gCHOKe are the AQM policy. The obtained results shows the behaviour of these algorithms. The paper presents also the implementation of AQM mechanisms in the router based on Linux.
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Authors and Affiliations

Jerzy Klamka
Adam Domański
Joanna Domańska
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Abstract

This paper presents non-linear mathematical model of a computer network with a part of wireless network. The article contains an analysis of the stability of the network based on TCP-DCR, which is a modification of the traditional TCP. Block diagram of the network model was converted to a form in order to investigate the D-stability using the method of the space of uncertain parameters. Robust D-stability is calculated for constant delays values.
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Authors and Affiliations

Jerzy Klamka
Jolanta Tańcula
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Abstract

Wireless Sensor Networks (WSNs) have existed for many years and had assimilated many interesting innovations. Advances in electronics, radio transceivers, processes of IC manufacturing and development of algorithms for operation of such networks now enable creating energy-efficient devices that provide practical levels of performance and a sufficient number of features. Environmental monitoring is one of the areas in which WSNs can be successfully used. At the same time this is a field where devices must either bring their own power reservoir, such as a battery, or scavenge energy locally from some natural phenomena. Improving the efficiency of energy harvesting methods reduces complexity of WSN structures. This survey is based on practical examples from the real world and provides an overview of state-of-the-art methods and techniques that are used to create energyefficient WSNs with energy harvesting.

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Authors and Affiliations

Bogdan Dziadak
Łukasz Makowski
Andrzej Michalski
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Abstract

The prediction of machined surface parameters is an important factor in machining centre development. There is a great need to elaborate a method for on-line surface roughness estimation [1-7]. Among various measurement techniques, optical methods are considered suitable for in-process measurement of machined surface roughness. These techniques are non-contact, fast, flexible and tree-dimensional in nature.

The optical method suggested in this paper is based on the vision system created to acquire an image of the machined surface during the cutting process. The acquired image is analyzed to correlate its parameters with surface parameters. In the application of machined surface image analysis, the wavelet methods were introduced. A digital image of a machined surface was described using the one-dimensional Digital Wavelet Transform with the basic wavelet as Coiflet. The statistical description of wavelet components made it possible to develop the quality measure and correlate it with surface roughness [8-11].

For an estimation of surface roughness a neural network estimator was applied [12-16]. The estimator was built to work in a recurrent way. The current value of the Ra estimation and the measured change in surface image features were used for forecasting the surface roughness Ra parameter. The results of the analysis confirmed the usability of the application of the proposed method in systems for surface roughness monitoring.

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Authors and Affiliations

Anna Zawada-Tomkiewicz
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Abstract

This paper presents a new test method able to infer - in periods of less than 7 seconds - the refrigeration capacity of a compressor used in thermal machines, which represents a time reduction of approximately 99.95% related to the standardized traditional methods. The method was developed aiming at its application on compressor manufacture lines and on 100% of the units produced. Artificial neural networks (ANNs) were used to establish a model able to infer the refrigeration capacity based on the data collected directly on the production line. The proposed method does not make use of refrigeration systems and also does not require using the compressor oil.
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Authors and Affiliations

Rodrigo Coral
Carlos A. Flesch
Cesar A. Penz
Maikon R. Borges
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Abstract

In this paper an artificial neural network, which realizes a nonlinear adaptive control algorithm, has been applied in a control system of variable speed generating system. The speed is adjusted automatically as a function of load power demand. The controller employs a single layer neural network to estimate the unknown plant nonlinearities online. Optimization of the controller is difficult because the plant is nonlinear and no stationary. Furthermore, it deals with the situation where the plant becomes uncontrollable without any restrictive assumptions. In contrast to previous work [1] on the same subject, the number of neural networks has been reduced to only one network. The number of the neurons in a network structure as well as choosing certain design parameters was specified a priori. The computer test results have been presented to show performance of proposed neural controller.

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Authors and Affiliations

L.M. Grzesiak
J. Sobolewski
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Abstract

The paper deals with linear circuits synthesis with periodic parameters. It was proved that the time-varying voltages and currents of inner branches of such circuits can be calculated using linear recursive equations with periodic coefficients if signals on port are given. The stability theorem of periodic solution was formulated. Hereby described the synthesis problems appear when compensation of power supply systems is considered.

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Authors and Affiliations

M. Siwczyński
M. Jaraczewski
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Abstract

This article describes queueing systems and queueing networks which are successfully used for performance analysis of different systems such as computer, communications, transportation networks and manufacturing. It incorporates classical Markovian systems with exponential service times and a Poisson arrival process, and queueing systems with individual service. Oscillating queueing systems and queueing systems with Cox and Weibull service time distribution as examples of non-Markovian systems are studied. Jackson's, Kelly's and BCMP networks are also briefly characterized. The model of Fork-Join systems applied to parallel processing analysis and the FES approximation making possible of Fork-Join analysis is also presented. Various types of blocking representing the systems with limited resources are briefly described. In addition, examples of queueing theory applications are given. The application of closed BCMP networks in the health care area and performance evaluation of the information system is presented. In recent years the application of queueing systems and queueing networks to modelling of human performance arouses researchers' interest. Hence, in this paper an architecture called the Queueing Network-Model Human Processor is presented.

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Authors and Affiliations

B. Filipowicz
J. Kwiecień
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Abstract

In the paper the squared voltage-current functionals are minimized, which represent the global power losses in the network. In that way it is possible to find the voltage-current distributions on the net without the use of immitance operators and basing only on the Kirchhoff laws. Farther the individual branch parameters are defined in the syntheses process. Many optimal power analysis examples are also shown to illustrate the thesis included in the paper.

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Authors and Affiliations

M. Siwczyński
M. Jaraczewski
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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

Self-aligning roller bearings are an integral part of the industrial machinery. The proper analysis and prediction of the various faults that may happen to the bearing beforehand contributes to an increase in the working life of the bearing. This study aims at developing a novel method for the analysis of the various faults in self-aligning bearings as well as the automatic classification of faults using artificial neural network (ANN) and deep neural network (DNN). The vibration data is collected for six different faults as well as for the healthy bearing. Empirical mode decomposition (EMD) followed by Hilbert Huang transform is used to extract instantaneous frequency peaks which are used for fault analysis. Time domain and time-frequency domain features are then extracted which are used to implement the neural networks through the pattern recognition tool in MATLAB. A comparative study of the outputs from the two neural networks is also performed. From the confusion matrix, the efficiency of the ANN has been found to be 95.7% and using DNN has been found to be 100%.
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Authors and Affiliations

Abhishek Rakesh
Arun Aravind
Babu T. Narendiranath
Mohamed Jahzan
Rama Prabha D.
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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

Malignant melanomas are the most deadly type of skin cancer, yet detected early have high chances of successful treatment. In the last twenty years, the interest in automatic recognition and classification of melanoma dynamically increased, partly because of appearing public datasets with dermatoscopic images of skin lesions. Automated computer-aided skin cancer detection in dermatoscopic images is a very challenging task due to uneven sizes of datasets, huge intra-class variation with small interclass variation, and the existence of many artifacts in the images. One of the most recognized methods of melanoma diagnosis is the ABCD method. In the paper, we propose an extended version of this method and an intelligent decision support system based on neural networks that uses its results in the form of hand-crafted features. Automatic determination of the skin features with the ABCD method is difficult due to the large diversity of images of various quality, the existence of hair, different markers and other obstacles. Therefore, it was necessary to apply advanced methods of pre-processing the images. The proposed system is an ensemble of ten neural networks working in parallel, and one network using their results to generate a final decision. This system structure enables to increase the efficiency of its operation by several percentage points compared with a single neural network. The proposed system is trained on over 5000 and tested afterwards on 200 skin moles. The presented system can be used as a decision support system for primary care physicians, as a system capable of self-examination of the skin with a dermatoscope and also as an important tool to improve biopsy decision making.

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Authors and Affiliations

Michał Grochowski
Agnieszka Mikołajczyk
Arkadiusz Kwasigroch

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