Mühendislik ve Doğa Bilimleri Fakültesi Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/1624

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Citation - WoS: 5
Citation - Scopus: 4
12th June 2017 Offshore Karaburun-Lesvos Island Earthquake Coseismic Deformation Analysis Using Continuous Gps and Seismological Data
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2021) Yıldız, Hasan; Çırmık, Ayça; Pamukçu, Oya; Özdağ, Özkan Cevdet; Gönenç, Tolga; Kahveci, Muzaffer
Understanding the tectonic mechanism generated by the earthquakes and faults is possible only if the preseismic, coseismic and postseismic crustal deformation related to the earthquakes is determined properly. By the analysis of continuous GPS (CGPS) coordinate time series, it is possible to estimate the crustal deformation. Besides, accelerometer records at strong motion stations (SMSs) may support the CGPS-based estimates. In this study, CGPS coordinate time series were analyzed in comparison with the accelerometer records for clarifying the coseismic deformation caused by the earthquake occurred in the surrounding of Lesvos fault located in the northern part of Karaburun within the active mechanism that controls the area where the earthquakes occurred during June 2017 on the offshore Karaburun. The activity of this fault continued throughout June 2017 until the time when the main shock (12th June 2017, M-W = 6.2) occurred. We analyzed CGPS coordinate time series of AYVL and CESM and DEUG stations to determine the coseismic deformation due to the offshore Karaburun-Lesvos Island earthquake using the empirical mode decomposition (EMD) method. Besides, the EMD method results were compared with the accelerometer records obtained from the SMSs close to the CGPS stations and CGPS-based results were found to be consistent with the accelerometer records. Additionally, the horizontal displacements were calculated by Coulomb 3.3 software using different focal plane solutions and compared with CGPS-based results. Consequently, it is suggested an integrated use of CGPS and strong motion accelerometer networks for the joint assessment of the crustal deformation and for the cost-effective use of existing observation networks as well as for the establishment of future observation networks at lower cost.
Citation - WoS: 1
Citation - Scopus: 1
An Accurate and Novel Numerical Simulation With Convergence Analysis for Nonlinear Partial Differential Equations of Burgers-Fisher Type Arising in Applied Sciences
(Walter De Gruyter Gmbh, 2022) Kürkçü, Ömür Kuvanc; Sezer, Mehmet
In this study, the second-order nonlinear partial differential equations of Burgers-Fisher type are considered under a unique formulation by introducing a novel highly accurate numerical method based on the Norlund rational polynomial and matrix-collocation computational system. The method aims to obtain a sustainable approach since it contains the rational structure of the Norlund polynomial. A unique computer program module, which involves very few routines, is constructed to discuss the precision and efficiency of the method and these few steps are described via an algorithm. A residual function is employed in both the error and convergence analyses with mean value theorem for double integrals. The considered equations in the numerical tests stand for model phenomena arising widely in applied sciences. Graphical and numerical comparisons provide a clear observation about the consistency of the method. All results prove that the method is highly accurate, eligible, and provides the ultimate operation for aforementioned problems.
Citation - WoS: 5
Citation - Scopus: 6
Adrenal Tumor Characterization on Magnetic Resonance Images
(WILEY, 2020) Barstuğan, Mücahid; Ceylan, Rahime; Asoğlu, Semih; Cebeci, Hakan; Koplay, Mustafa
Adrenal tumors occur on adrenal glands and are generally detected on abdominal area scans. Adrenal tumors, which are incidentally detected, release vital hormones. These types of tumors that can be malignant affect body metabolism. Both of benign and malign adrenal tumors can have a similar size, intensity, and shape, this situation may lead to wrong decision during diagnosis and characterization of tumors. Thus, biopsy is done to confirm diagnosis of tumor types. In this study, adrenal tumor characterization is handled by using magnetic resonance images. In this way, it is wanted that patient can be disentangled from one or more imaging modalities (some of them can includes X-ray) and biopsy. An adrenal tumor image set, which includes five types of adrenal tumors and has 112 benign tumors and 10 malign tumors, was used in this study. Two data sets were created from the adrenal tumor image set by manually/semiautomatically segmented adrenal tumors and feature sets of these data sets are constituted by different methods. Two-dimensional gray-level co-occurrence matrix (2D-GLCM), gray-level run-length matrix (GLRLM), and two-dimensional discrete wavelet transform (2D-DWT) methods were analyzed to reveal the most effective features on adrenal tumor characterization. Feature sets were classified in two ways: benign/malign (binary classification) and type characterization (multiclass classification). Support vector machine and artificial neural network classified feature sets. The best performance on benign/malign classification was obtained by the 2D-GLCM feature set. The best results were assessed with sensitivity, specificity, accuracy, precision, and F-score metrics and they were 99.17%, 90%, 98.4%, 99.17%, and 99.13%, respectively. The highest classification performance on type characterization was obtained by the 2D-DWT feature set as 59.62%, 96.17%, 93.19%, 54.69%, and 54.94% for sensitivity, specificity, accuracy, precision, and F-score metrics, respectively.
Citation - WoS: 18
Citation - Scopus: 24
Adsorption of Cr(vi) Onto Cross-Linked Chitosan-Almond Shell Biochars: Equilibrium, Kinetic, and Thermodynamic Studies
(SPRINGER INTERNATIONAL PUBLISHING AG, 2021) Altun, Türkan; Ecevit, Hüseyin; Kar, Yakup; Çiftçi, Birsen
In this study, to remove Cr(VI) from the solution environment by adsorption, the almond shell was pyrolyzed at 400 and 500 degrees C and turned into biochar (ASC400 and ASC500) and composite adsorbents were obtained by coating these biochars with chitosan (Ch-ASC400 and Ch-ASC500). The resulting biochars and composite adsorbents were characterized using Fourier transform infrared (FTIR) spectroscopy; Brunauer, Emmett, and Teller (BET) surface area; scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX); and the point of zero charge pH (pH(pzc)) analyses. The parameters affecting the adsorption were examined with batch adsorption experiments and the optimum parameters for the efficient adsorption of Cr(VI) in 55 mg L-1 solution were determined as follows; adsorbent dosages: 5 g L-1 for biochars, 1.5 g L-1 for composite adsorbents, contact time: 120 min, pH: 1.5. It was seen that the temperature did not affect the adsorption much. Under optimum conditions, Cr(VI) adsorption capacities of ASC400, ASC500, Ch-ASC400, and Ch-ASC500 adsorbents are 11.33, 11.58, 37.48, and 36.65 mg g(-1), respectively, and their adsorption percentages are 95.2%, 97.5%, 94.3%, and 94.0%, respectively. Adsorption data were applied to Langmuir, Freundlich, Scatchard, Dubinin-Radushkevic, and Temkin isotherms and pseudo-first-order kinetic model, pseudo-second-order kinetic model, intra-particle diffusion model, and film diffusion model. The adsorption data fitted well to the Langmuir isotherm and pseudo-second-order kinetic models. From these results, it was determined that chemical adsorption is the dominant mechanism. Also, both intra-particle diffusion and film diffusion is effective in the adsorption rate. For all adsorbents, the Langmuir isotherm proved to be the most appropriate model for adsorption. The maximum monolayer adsorption capacities calculated from this model are 24.15 mg g(-1), 27.38 mg g(-1), 54.95 mg g(-1), and 87.86 mg g(-1) for ASC400, ASC500, Ch-ASC400, and Ch-ASC500, respectively. The enthalpy change, entropy change, and free energy changes during the adsorption process were calculated and the adsorption was also examined thermodynamically. As a result, adsorption occurs spontaneously for all adsorbents.
Citation - WoS: 12
Citation - Scopus: 11
Aerodynamic Optimization of a Swept Horizontal Axis Wind Turbine Blade
(ASME, 2021) Kaya, Mehmet Numan; Köse, Faruk; Uzol, Oğuz; Ingham, Derek; Ma, Lin; Pourkashanian, Mohamed
The aerodynamic shapes of the blades are still of high importance and various aerodynamic designs have been developed in order to increase the amount of energy production. In this study, a swept horizontal axis wind turbine blade has been optimized to increase the aerodynamic efficiency using the computational fluid dynamics method. To illustrate the technique, a wind turbine with a rotor diameter of 0.94 m has been used as the baseline turbine, and the most appropriate swept blade design parameters, namely the sweep start-up section, tip displacement, and mode of the sweep have been investigated to obtain the maximum power coefficient at the design tip speed ratio. At this stage, a new equation that allows all three swept blade design parameters to be changed independently has been used to design swept blades, and the response surface method has been used to find out the optimum swept blade parameters. According to the results obtained, a significant increase of 4.28% in the power coefficient was achieved at the design tip speed ratio with the newly designed optimum swept wind turbine blade. Finally, baseline and optimum swept blades have been compared in terms of power coefficients at different tip speed ratios, force distributions, pressure distributions, and tip vortices.
Citation - Scopus: 77
Alginate-Coated Perlite Beads for the Efficient Removal of Methylene Blue, Malachite Green, and Methyl Violet From Aqueous Solutions: Kinetic, Thermodynamic, and Equilibrium Studies
(Springer, 2019) Parlayıcı, Şerife
Environmental pollution has been increasing recently due to industrialization. Many industries use dyestuffs to color their products. This work investigates the adsorption of methylene blue (MB), malachite green (MG), and methyl violet (MV) on alginate-coated perlite beads (AP). AP was prepared by a sol-gel process. The removal of MB, MG, and MV from aqueous solutions by AP as an adsorbent was tested by using a batch-type model. In order to prove the effectiveness of the study, it has been tried to obtain optimum efficiency at optimum level by working depending on mixing time (minutes), initial dye concentration (ppm), adsorbent dose (mg/L), pH, and temperature (°C). The results showed that the MB, MG, and MV adsorption process reached equilibrium within a 60-min period for AP. It has been found that the amount of adsorbed dyestuff increases with the initial dye concentration, the pH of the solution. Thermodynamic activation parameters were calculated from experimental data at different temperatures. The AP was characterized by Fourier Transform Infrared Spectroscopy (FT-IR) before and after MB, MG, and MV adsorption. The equilibrium adsorption data were described by Langmuir, Freundlich, Scatchard, Temkin and D-R isotherms. The modified Langmuir isotherm was applied to explain the experimental adsorption, and the greatest MB, MG, and MV adsorption capacity of the AP reached to 104.1, 74.6, and 149.2 mg/g, respectively. The pseudo-first and pseudo-second-order equations were used to evaluate the kinetic data, and the constants are determined. The best correlation coefficients were well described using the pseudo-second-order kinetic model. As a result, AP has claimed the possibility as an adsorbent for MB, MG, and MV removal from dilute aqueous solutions. © 2019, The Author(s).
Citation - WoS: 5
Citation - Scopus: 7
Alternative Approach for Safe Disposal of Dry Olive Pomace: Pyrolysis With/Without Physical Preprocessing
(SPRINGER, 2020) Dinç, Gamze; Yel, Esra
The aim of this study is to present an alternative approach for disposal by using pyrolysis for dry olive pomace (which is the leftover portion of raw olive pomace), which constitutes a problem in olive oil production facilities. In this context, dry olive pomace was pyrolyzed at 600 degrees C and two different pyrolysis durations: 5 degrees C/min heating rate without retention (total pyrolysis duration is 80 min) and 1 degrees C/min heating rate with 30-min retention after reaching target pyrolysis temperature (total pyrolysis duration is 550 min). Afterward, the effects of the dry olive pomace mixed with the olive mill wastewater and the pomace particle size during the pyrolysis process were evaluated in terms of pyrolysis product yields, inorganic contents of chars and organic fractions of bio-oil. While mixing of pomace within the wastewater resulted in an increase in the pyrolysis liquid, the effects of pomace particle size on pyrolysis product yields changed based on the pyrolysis conditions. A decrease in the particle size from 2 to 0.85 mm resulted in an increase in gas by 37.3% and a decrease in liquid by 37% at the pyrolysis process of 80 min. Furthermore, the decrease in the pomace size in grinding preprocess enhanced pyrolysis liquid quality in terms of a decrease in oxygenated compounds by 5-13% and an increase in aliphatic compounds by 7-20% at both pyrolysis durations. Consequently, dry olive pomace pyrolysis can be stated as one of the effective alternatives for safe disposal by converting waste into useful end products. Graphic abstract
Citation - WoS: 9
Citation - Scopus: 10
Alternative System Design for High Temperature Solid Particle Erosion Wear Problem
(SPRINGER/PLENUM PUBLISHERS, 2021) Demirci, Musa; Bağcı, Mehmet
In order to simulate the wear behavior of materials subjected to solid particle erosion due to high temperature as well as velocity effect in operating conditions such as power plants and jet engines, ASTM G76 standard is not sufficient and test rig compliant with ASTM G211-14 standard must be put forward. In this context, a test rig, alternative to existing systems where solid particle erosion wear experiments can be performed in compliance with high temperature (similar to 700 degrees C) and particle impact velocity (similar to 150 m/s) conditions, has been designed and produced. In order to ensure the widespread use of this test rig, a resistance wire system was used to reach high temperatures of the heating system by achieving a different design solution. In the setup of this design, the perfect gas equation, heating power and ohm laws are also used. In addition, the designs of specimen fixture and particle feeding system, which are the determining parameters in erosion wear tests, have been updated. With the produced test rig; solid particle erosion experiments were carried out using Inconel 718 test specimens at 600 degrees C temperature, similar to 97 m/s erosive particle impact velocity and three different erosive particle impact angles (30 degrees, 60 degrees and 90 degrees). In the experiments, especially the change of temperature over time was confirmed by the data obtained from both the test rig and the specimens. Graphic
Citation - Scopus: 20
Analysis and Investigation of Different Advanced Control Strategies for High-Performance Induction Motor Drives
(Universitas Ahmad Dahlan, 2020) Farah, Nabil; Talib, Hairul Nizam; Ibrahim, Z.B.; Abdullah, Q.; Aydoğdu, Ömer; Rasin, Z.; Lazi, J.M.
Induction motor (IM) drives have received a strong interest from researchers and industry particularly for high-performance AC drives through vector control method. With the advancement in power electronics and digital signal processing (DSP), high capability processors allow the implementation of advanced control techniques for motor drives such as model predictive control (MPC). In this paper, design, analysis and investigation of two different MPC techniques applied to IM drives; the model predictive torque control (MPTC) and model predictive current control (MPCC) are presented. The two techniques are designed in Matlab/Simulink environment and compared in term of operation in different operating conditions. Moreover, a comparison of these techniques with field-oriented control (FOC) and direct torque control (DTC) is conducted based on simulation studies with PI speed controller for all control techniques. Based on the analysis, the MPC techniques demonstrates a better result compared with the FOC and DTC in terms of speed, torque and current responses in transient and steady-state conditions. © (2020). All rights reserved.
Citation - WoS: 7
Citation - Scopus: 8
An Analysis of the Effect of Pressure Angle Change on Bending Fatigue Performance in Asymmetrical Spur Gears
(SAGE PUBLICATIONS LTD, 2021) Demet, Seyit Mehmet; Ersoyoğlu, Ali Serhat
In this study, the fatigue performances of symmetrical and asymmetrical spur gears were analyzed by performing single tooth bending fatigue tests. The gears tested were determined to be symmetrical spur gears with a 20 degrees/20 degrees pressure angle, asymmetrical spur gears with a 20 degrees/22 degrees pressure angle, and asymmetrical spur gears with a 20 degrees/25 degrees pressure angle. These gears were made of AISI 4140 material. Single tooth bending fatigue tests were performed under variable loads. Considering the tests performed at the same torque values in asymmetrical spur gears with a 20 degrees/22 degrees pressure angle compared to symmetrical spur gears with a 20 degrees/20 degrees pressure angle, a statistically significant increase in performance was achieved at close to 90%. While gears with 20 degrees/20 degrees and 20 degrees/22 degrees pressure angles break at the tooth root, tooth flank fracture was observed in relatively high numbers of cycles in asymmetric spur gears with a 20 degrees/25 degrees pressure angle. It was observed that the formation of tooth flank damage negatively affected the fatigue performance.
Citation - Scopus: 4
Analysis of the Studies Done on Laboratories in Turkey
(Ekip Buro Makineleri A., 2020) Yener, Dündar; Köklü, Niğmet; Yamaç, Ramazan Ziya; Yalçın, Seher
The aim of this study is to determine the trend of studies in the laboratory and put the current situation in Turkey. For this purpose, document analysis technique, one of the qualitative research methods, was used in the research. The data group of the research consists of thesis studies on laboratories in our country between 1999-2017. Theses in the fields of science, physics, chemistry, and biology have been determined and themes and sub-themes have been created through the keywords of these theses. Then, frequency tables were created according to the themes and sub-themes created. According to the findings obtained, it was seen that the traditional laboratory approach and inquiry-based laboratory approaches are compared in the studies. It was determined that the studies were done on physics subjects and it was determined that complementary measurement and evaluation studies performed for performance evaluation were used in very few numbers. In addition, it was concluded that the keywords did not give enough information about the studies. In this context, it can be suggested to examine the effectiveness of these approaches according to each other and experiment types by examining the approaches in which students can be more active in laboratories. © 2020. All Rights Reserved.
Analytical Study on the Effect of Corrosion To the Construction Performance
(2019) Koçer, Mustafa; Öztürk, Murat; Boğa, Ahmet Raif
Corrosion is one of the most important factor to achieve in completing the service life of reinforced concrete structures also cause significant losses in energy damping capacities of structures. In this study, the reinforced concrete column designed in ½ geometrical scale was subjected to accelerated corrosion test for 26.5 days under 1 ampere constant current. As a result of the experiment, weight loss and strength reductions was obtained. Loss of strength in reinforcement due to corrosion damage was obtained with experimental procedure. Loss of cross section and reduction of compressive strength of concrete were obtained with empirical formulas in the literature. Thanks to this data, 3 different scenarios applied on a sample building in Hatay province. Static pushover analyzes of the sample building designed in accordance with the regulations were carried out with Sap 2000 program under the specified corrosion scenarios. The load-displacement curves obtained by the scenarios are compared with the curves of the reference building. As a result of the comparisons, it was observed that corrosion damage caused significant loss in horizontal load carrying capacity of the building. The corrosion scenarios show that corrosion in columns or beams changes collapse modes of the structure.
Citation - WoS: 35
Citation - Scopus: 47
Application of Sequencing Batch Biofilm Reactor (sbbr) in Dairy Wastewater Treatment
(KOREAN INSTITUTE CHEMICAL ENGINEERS, 2019) Öztürk, Arzu; Aygün, Ahmet; Nas, Bilgehan
Application of lab-scale sequencing batch (SBR) and sequencing batch biofilm reactors (SBBR) for treatment of dairy wastewater was investigated under organic loading of 1,130-1,560 gBOD(5)/m(3)d. The main characteristics of the dairy wastewater were: pH=4.9, chemical oxygen demand (COD)=16,264 mg/l; biological oxygen demand (BOD5)=10,536 mg/l, PO4-P=342 mg/l; total nitrogen (TN)=224 mg/l. SBBR was filled with the Kaldnes K1 biocarrier at 30% of the volume of empty reactor. The SBR and SBBR were operated in fixed 24 h cycles, each consisting of 30 min fill up, 22 h aeration, 1.5 h settle, 30 min decant, and idle with a hydraulic retention time (HRT) of 8 days. Operational parameters such as pH, dissolved oxygen (DO), mixed liquor suspended solid (MLSS), solids retention time (SRT) and sludge volume index (SVI) were monitored during the whole cycle. The effects of these parameters on the COD, nitrogen and phosphorus removal were discussed in this paper. As a result, adding biocarrier to the reactor had a positive effect on organic with COD removal of 63.5% for SBR and 81.8% for SBBR and nutrient removal with ammonium removal of 66.0% for SBR and 85.1% for SBBR in treatment of dairy wastewater.
Citation - WoS: 8
Citation - Scopus: 8
Application of the Central Composite Design and Response Surface Methodology for Investigation of Induction Time, Conjugated Diene, Conjugated Triene and Trans Fatty Acid Content of Corn Oil Enriched With Carotenoids
(SPRINGER, 2020) Topkafa, Mustafa
The central composite design technique was used to investigation of induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil enriched with lutein, beta-carotene and lycopene in this study. The levels of lutein and beta-carotene and were between 0 and 94 mg/kg, while lycopene levels was 0-49.56 mg/kg. Oil samples with and without lutein, beta-carotene and lycopene were prepared according to central composite design. The influence of these three independent variables on the four dependent variables such as time, conjugated diene and conjugated triene and trans fatty acid content was evaluated using a reduced cubic model. The each independent variable was effective on the induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil. The positive effect on the induction time was observed high concentrations of lutein and lycopene concentrations. Lutein, beta-carotene and lycopene had a significant effect on conjugated diene, conjugated triene and trans fatty acid content. The desirability function and the 3D plots suggested that optimum parameters were lutein concentration of 19 mg/kg, beta-carotene concentration of 19 mg/kg and lycopene concentration of 12.5 mg/kg as optimum parameters for maximum induction time and the minimum formation of conjugated diene, conjugated triene and trans fatty acid species.
Citation - WoS: 13
Citation - Scopus: 18
Application of the Maturity Model in Industrial Corporations
(Mdpi, 2022) Ünal, Cihan; Sungur, Cemil; Yıldırım, Hakan
Enterprises need to evaluate for themselves whether they are ready for Industry 4.0 to survive and develop in the era of the Fourth Industrial Revolution. Therefore, it is necessary to conceptualize or develop an Industry 4.0 readiness and maturity model with basic model dimensions. The present study aimed to review the maturity models available in the literature and to develop and implement a comprehensive maturity model that would eliminate the problems in the existing models. Most maturity models developed lack vital dimensions such as laws, incentives, and corporate culture. While developing the model, AHP and expert opinions were used to determine the dimension weights. The model was applied to 87 businesses in various industries at the Ankara Chamber of Industry Industrial Park in Turkey. The developed model calculates the maturity level of the enterprise for six dimensions. The data on 61 corporations where Industry 4.0 technologies were adopted were analyzed based on demographic variables such as the year of establishment, industry, size, capital, and turnover. These findings demonstrated that Industry 4.0 was introduced recently in Turkey and businesses are required to take further steps to keep up with the global digital transformation. Since the number of industries and corporations that are aware of the Industry 4.0 technologies is limited in Ankara, Turkey, only a few businesses adopted the Industry 4.0 technologies. This developed model will make an important contribution to the literature with its unique dimensions. It would pave the way for further research in various industries in Turkey and other nations where Industry 4.0 investments are new.
Citation - WoS: 25
Citation - Scopus: 25
Application of Various Carboxylic Acids Modified Walnut Shell Waste as Natural Filler for Epoxy-Based Composites
(WILEY, 2021) Albaker, Ruya Isam Bakr; Kocaman, Süheyla; Martı, Mustafa Esen; Ahmetli, Gülnare
In this study, chemically modified walnut shells (WS) were used as the filling material for synthesis of bio-based epoxy composites and added to the matrix at varied mass ratios (10%-50%). The shells were initially treated with alkali and then modified with three different organic acids (citric acid [CA], oxalic acid [OA], and formic acid [FA]). The WS were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX) and thermo gravimetric analyzer. The SEM and X-ray diffraction were employed to observe the morphology of the composites. The influences of acid type and WS percentages on the mechanical, thermal and water sorption properties were investigated. The maximum tensile strength (124.8 MPa) was obtained with CA-treated shells (CA-WS) and followed by OA-treated shells (OA-WS) (117 MPa) and FA-treated shells (FA-WS) (96.5 MPa). Acid modification had a positive effect on Young's modulus as that of epoxy resins increased by 5.45%-50.91%. The treatment did not significantly affect hardness. The optimum amount of modified shells in the composites was found to be 20 wt%. Water sorption values changed in the range of 2.78%-3.42% for composites with 20 wt% WS and observed to increase with the filler amount in the composite. However, this trend and the slight decrease in thermal properties are not critical obstacles for the use of modified WS in the manufacture of inexpensive epoxy- and bio-based eco-friendly products.
Citation - WoS: 1
Citation - Scopus: 3
An Approach for Learning From Robots Using Formal Languages and Automata
(EMERALD GROUP PUBLISHING LTD, 2019) Aslan, Muhammet Fatih; Durdu, Akif; Sabancı, Kadir; Erdogan, Kemal
Purpose In this study, human activity with finite and specific ranking is modeled with finite state machine, and an application for human-robot interaction was realized. A robot arm was designed that makes specific movements. The purpose of this paper is to create a language associated to a complex task, which was then used to teach individuals by the robot that knows the language. Design/methodology/approach Although the complex task is known by the robot, it is not known by the human. When the application is started, the robot continuously checks the specific task performed by the human. To carry out the control, the human hand is tracked. For this, the image processing techniques and the particle filter (PF) based on the Bayesian tracking method are used. To determine the complex task performed by the human, the task is divided into a series of sub-tasks. To identify the sequence of the sub-tasks, a push-down automata that uses a context-free grammar language structure is developed. Depending on the correctness of the sequence of the sub-tasks performed by humans, the robot produces different outputs. Findings This application was carried out for 15 individuals. In total, 11 out of the 15 individuals completed the complex task correctly by following the different outputs. Originality/value This type of study is suitable for applications to improve human intelligence and to enable people to learn quickly. Also, the risky tasks of a person working in a production or assembly line can be controlled with such applications by the robots.
Citation - WoS: 24
Citation - Scopus: 23
Artificial Bee Colony Algorithm for Solving Multi-Objective Distributed Fuzzy Permutation Flow Shop Problem
(IOS Press BV, 2022) Baysal, Mehmet Emin; Sarucan, Ahmet; Büyüközkan, Kadir; Engin, Orhan
The distributed permutation flow shop scheduling (DPFSS) is a permutation flow shop scheduling problem including the multi-factory environment. The processing times of the jobs in a real life scheduling problem cannot be precisely know because of the human factor. In this study, the process times and due dates of the jobs are considered triangular and trapezoidal fuzzy numbers for DPFSS environment. An artificial bee colony (ABC) algorithm is developed to solve the multi-objective distributed fuzzy permutation flow shop (DFPFS) problem. First, the proposed ABC algorithm is calibrated with the well-known DPFSS instances in the literature. Then, the DPFSS instances are fuzzified and solved with the algorithm. According to the results, the proposed ABC algorithm performs well to solve the DFPFS problems. © 2022 - IOS Press. All rights reserved.
Citation - WoS: 11
Citation - Scopus: 19
Artificial Intelligence in Healthcare Competition (teknofest-2021): Stroke Data Set
(AVES, 2022) Koç, U.; Sezer, E.A.; Özkaya, Y.A.; Yarbay, Y.; Taydaş, O.; Ayyıldız, V.A.; Bahadır, Murat
Objective: The artificial intelligence competition in healthcare was organized for the first time at the annual aviation, space, and technology festival (TEKNOFEST), Istanbul/Türkiye, in September 2021. In this article, the data set preparation and competition processes were explained in detail; the anonymized and annotated data set is also provided via official website for further research. Materials and Methods: Data set recorded over the period covering 2019 and 2020 were centrally screened from the e-Pulse and Teleradiology System of the Republic of Türkiye, Ministry of Health using various codes and filtering criteria. The data set was anonymized. The data set was prepared, pooled, curated, and annotated by 7 radiologists. The training data set was shared with the teams via a dedicated file transfer protocol server, which could be accessed using private usernames and passwords given to the teams under a non-disclosure agreement signed by the representative of each team. Results: The competition consisted of 2 stages. In the first stage, teams were given 192 digital imaging and communications in medicine images that belong to 1 of 3 possible categories namely, hemorrhage, ischemic, or non-stroke. Teams were asked to classify each image as either stroke present or absent. In the second stage of the competition, qualifying 36 teams were given 97 digital imaging and communications in medicine images that contained hemorrhage, ischemia, or both lesions. Among the employed methods, Unet and DeepLabv3 were the most frequently observed ones. Conclusion: Artificial intelligence competitions in healthcare offer good opportunities to collect data reflect-ing various cases and problems. Especially, annotated data set by domain experts is more valuable. © 2022, AVES. All rights reserved.
Citation - WoS: 13
Citation - Scopus: 14
Assessing the Performance of Bds-3 for Multi-Gnss Static and Kinematic Ppp-Ar
(Elsevier Ltd, 2022) Öğütçu, S.; Alcay, S.; Özdemir, Behlül Numan; Li, P.; Zhang, Y.; Konukseven, C.; Atiz, O.F.
As of 2021, a total of four different GNSS constellations – namely, GPS, GLONASS, Galileo, and BDS-3 – can be used with Full Operational Capability (FOC). In this work, the contribution of BDS-3 FOC to GPS + GLONASS + Galileo (GRE) PPP-AR is investigated, considering the three different cut-off angles (7°, 30°, and 45°) and different lengths of static observation sessions (24-, 12-, 6-, 3-, 1-, 0.5-, 0.25-hour). The data of 31 IGS-MGEX stations is processed with GRE PPP-AR and GREC3 (GPS + GLONASS (using float mode) + Galileo + BDS-3) PPP-AR modes. The results showed that BDS-3 degraded the horizontal (except for 24-h sessions) and vertical accuracy of static GRE PPP-AR solutions regardless of the elevation cutoff angle and observation time. The kinematic results showed that BDS-3 significantly contributed to the accuracy of GRE kinematic PPP-AR for 30° and 45° cutoff angles. The convergence time analysis showed that BDS-3 only contributes to GRE kinematic PPP-AR for the vertical component. © 2022 COSPAR

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