Hanzele BULUT, Fırat KAÇAR
Hanzele BULUT, Fırat KAÇAR
Supervisory control and data acquisition (SCADA) systems appear as smart technology products that are easy to control, provide fast communication, transmit data to
relevant institutions, observed, informed and provide storage. These are the systems that inform the relevant unit of all activations that may occur in cases of sudden
intervention, from industry to energy and from communication to banking systems. Supervisory control and data acquisition systems store thousands of data on
monetary systems. In this article, the prevention of cyberattacks on SCADA systems used in the financial field is discussed. In the introduction part of the article, studies
on cyber security are included and the importance of establishing information security policies and putting them into practice is mentioned. In the Materials and
Methods section, a simulation of a possible attack on SCADA systems used in the financial field has been created and system vulnerabilities have been identified for this
scenario and the results obtained as a result of exploiting the relevant vulnerabilities are given. In the Evaluation and Suggestions section, the results and evaluations
of the findings obtained through vulnerability scans and attack analyzes within the scope of the relevant scenario are given and the measures to be taken are included.
In addition, in the light of the information obtained in the literature research, what needs to be done to increase the security of SCADA networks has been specified. In
the last section, the importance of cyber attacks, depending on the developments in the future, is mentioned by giving the access requirements, necessary times and
flow chart for the attacks carried out within the scope of the scenario.
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Uğur ALCAN, Fırat KAÇAR
Uğur ALCAN, Fırat KAÇAR
With the internet brought along by technology, people have started to produce data in almost all their jobs. We create a huge data source with many activities we
cannot count, such as sending messages on Whatsapp, sharing photos on Instagram, searching in Google, and sending electronic mails (email) and this process
is repeated every single day. Such dense and different data also lead to information garbage. Analyzing this dump with traditional technologies has been another
problem. Big companies that are interested to analyze this mass information, analyze the behavior of their customers, and determine their strategies according to the
results obtained have come up with the concept of big data. Big data are the form of the data we obtain from different sources such as social media shares, sensor data,
photo archives, call records obtained from Global System for Mobile Communications (GSM) operators, and search engine statistics, into a meaningful and processable
form [1]. In this study, the effect of the coronavirus disease 2019 pandemic, which is an important problem of today, on Istanbul traffic has been examined by using
the power of big data technologies. In this context, the hourly traffic index of the 2020 dataset which has openly been published by Istanbul Metropolitan Municipality
[2], and the curfew time dataset is discussed. Apache Spark, a new generation data processing tool, has been used in the analysis of these datasets. With Apache
Spark, first, general analysis of the Istanbul traffic index data for 2020 has been carried out, and then, the data obtained have been checked whether it is associated
with the curfew time dataset and impact analysis has been performed. Elasticsearch has been utilized to keep the processed data, and Kibana has been used for data
visualization. At the end of the study, machine learning applications on traffic density have been enhanced using Apache Spark's machine learning library, Application
Programming Interface (API) with logistic regression, decision trees, random forest, gradient-boosted tree-based OneVsRest, and linear support vector machine-based
OneVsRest methods.
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In this study, a new simulated grounded inductor (SGI) is developed. It has a simple structure because it employs two-terminal active devices (TTADs). Moreover, it
has a minimum number of passive elements, considering the TTAD-based configurations. However, there is a single passive element-matching constraint for two
resistors. Derived from the developed SGI, a second-order voltage-mode universal filter application is given. With proper connection of inputs, it yields band-pass (BP),
high-pass (HP), low-pass (LP), all-pass (AP), and notch filter (NF) responses. The performance of the developed circuits is verified through the SPICE simulation program.
Additionally, an experimental test result is given for the developed SGI.
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Jian WU, Jing XU, Weixun QIN, Jianfeng WANG, Mugen WU
Jian WU, Jing XU, Weixun QIN, Jianfeng WANG, Mugen WU
In the entire power system operation, the cable is an essential and important component. However, the internal structure of the cable joint is complex and the material
has diverse characteristics, which can easily lead to electric field distortion and power failure. Based on this, in order to reduce the occurrence of such problems and
improve the safety of cable operation, this paper calculates and analyzes the stress cone parameters of the main insulation layer of a 10 kV cable, and optimizes its
structural electric field. Specifically, the formulas of stress cone, reaction force cone, and thickness of the wound-insulating layer are designed, and the parameters are
calculated. The results show that the maximum radius Rm of enhanced insulation is 28 mm, the thickness ΔR of enhanced insulation of the cable terminal is 13 mm,
etc. The appropriate optimization parameters are then selected, and the electric fields of the shielded pipe structure, stress cone structure, and accessory body are
optimized, and a reasonable optimization approach is given
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A quasistatic approach was used to consider the occurrence of additional pulses (APs) in the modal filter (MF) realized on a double-sided printed circuit board, as well
as in the three structures obtained from it by removing one reference conductor. It is shown that, for all investigated MFs, the AP delays are determined by a linear
combination of per-unit-length mode delays multiplied by the line length. It was found that there are no APs between the pulses of modes with one pass along the
line, while they appear with three or more passes. It is revealed that in each of the considered MF structures (except the one without upper-right reference conductor),
the APs have greater amplitudes of mode pulses with a triple pass. It was demonstrated that the removal of the reference conductors affects the number, polarity, and
amplitude of the APs.
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In recent years, industrial developments have made it necessary to control induction motors, used in both industrial and household applications, over a wide range of
speeds. Thanks to vector-control algorithms, in order to control the torque in high-performance operations over wide-ranging speeds, the equivalent circuit parameters
of the induction motor have to be known precisely.
In this study, the equivalent circuit parameters of the induction motor are estimated only with the limited information shared by the manufacturer’s datasheets.
The estimation method is based on the principle of solving nonlinear equations derived from the equivalent circuit of an induction motor by the particle swarm
optimization algorithm. The proposed equation set and the algorithmic solution have been tested for 20 different induction motors and presented in comparison with
the experimentally obtained equivalent circuit parameters. Moreover, the speed–torque characteristics obtained experimentally and calculated from the estimated
equivalent circuit parameters for ten different selected motors are compared and the performance of the proposed algorithm is examined.
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Yasemin POYRAZ KOÇAK, Selçuk SEVGEN
Yasemin POYRAZ KOÇAK, Selçuk SEVGEN
Quantum teleportation is a technique of sending information from one place to another place. Distance between two points can be hundreds of thousands of lightyears. For quantum teleportation, there is no need for a channel between two points when sending a state vector from one place to another. Since classical information
sharing is possible, it is also possible to send a state vector from one place to another place. Teleportation is the transfer of a quantum state from one place to another
through classical channels. Superdense coding, a dual to teleportation, uses a single quantum bit to transmit two bits classical information. Superdense coding uses a
qubit to transfer two classical bits, while teleportation performs one qubit transfer using two classical bits. In this article, teleportation, superdense coding algorithms,
and the Bell’s inequality test in which Bell’s inequality is violated with quantum mechanics are performed on both Qiskit and International Business Machines circuit
composer, and results are compared and presented in detail. The results revealed that whether a faster-than-light signal transfer is possible using quantum mechanics
depends on whether a copy of the quantum state is created or not. Finally, Bell’s inequality created by classical logic violated by quantum mechanics is shown by
experimental results.
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Murat KAYRİ, Cengiz İPEK, Davut İZCİ, Erdal EKER
Murat KAYRİ, Cengiz İPEK, Davut İZCİ, Erdal EKER
This paper proposes a novel sine–cosine and Nelder–Mead (SCANM) algorithm which hybridizes the sine–cosine algorithm (SCA) and Nelder–Mead (NM) local search
method. The original version of SCA is prone to early convergence at the local minimum. The purpose of the SCANM algorithm is to overcome this issue. Thus, it aims
to overcome this issue with the employment of the NM method. The SCANM algorithm was firstly compared with the SCA algorithm through 23 well-known test
functions. The statistical assessment confirmed the better performance of the proposed algorithm. The comparative convergence profiles further demonstrated the
significant performance improvement of the proposed SCANM algorithm. Besides, a non-parametric test was performed, and the results that showed the ability of the
proposed approach were not by coincidence. A popular and well-performed metaheuristic algorithm known as grey wolf optimization was also used along with the
recent and promising two other algorithms (Archimedes optimization and Harris hawks optimization) to comparatively demonstrate the performance of the SCANM
algorithm against well-known classical benchmark functions and CEC 2017 test suite. The comparative assessment showed that the SCANM algorithm has promising
performance for optimization problems. The non-parametric test further verified the better capability of the proposed SCANM algorithm for optimization problems.
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Murat ÖZEV, Zafer ORTATEPE, Ahmet KARAARSLAN
Murat ÖZEV, Zafer ORTATEPE, Ahmet KARAARSLAN
In this study, implementation of incremental fuzzy control (IFC) method on field programmable gate array (FPGA) is investigated for gimbals and fins of missiles that
include brushless direct current (BLDC) motors and its comparison with conventional proportional-integral (PI) control method are analyzed. BLDC motors are widely
used in two important parts of guided missiles due to their high performance. Firstly, gimbals usually consist of seeker cameras, whose axis controls are provided by
BLDC motors. These motors provide two axis seeker camera motions, so that the missiles can trace the target. Secondly, missiles can be guided to intended direction by
BLDC motors that are used in the control system of fins. According to these important roles, controlling of BLDC motors is very important for defense industry. Therefore,
performance of FPGA-based conventional PI and proposed IFC methods on BLDC motors are analyzed in detailed in terms of both simulation and experimental study.
Simulation results are obtained by using MATLAB/Simulink program. Also, an FPGA-based test bench is used for experimental studies. Results obtained from simulation
and experimental set up are compared and it is proved that the implementation of proposed IFC method improves the BLDC motor performance used in missiles
compared to the conventional PI control method.
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Ebru EFEOĞLU, Gürkan TUNA
Ebru EFEOĞLU, Gürkan TUNA
With the advancement of technology, the use of machine learning techniques has increased. The need for the prevention of terrorist attacks has brought upon the
use of machine learning techniques to explosive detection. Flammable liquids such as alcohol are easily available and widely used in various terrorist attacks. In this
study, a new microwave measurement system is developed and a hybrid clustering approach is proposed to classify liquids. With the proposed measurement system,
the reflection coefficient (S11 parameter) of liquids in bottles is measured at room temperature and these measurements are used as inputs by the proposed clustering
algorithm. The results obtained using the proposed clustering algorithm are compared with the results obtained using a set of well-known clustering algorithms,
that is, K-means, hierarchical clustering, farthest first, and fuzzy C-means, in order to make a fair comparison. The results show that the proposed clustering algorithm
provides 100% accuracy and is superior to the well-known algorithms used in this study. The results will enable us to manufacture a low-cost liquid scanner for railway
stations and shopping malls as well as small airports. The proposed liquid scanner’s design was completed, and the manufacturing phase has been started.
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