Konya Mühendislik Bilimleri Dergisi

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/2243

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Active Vibration Control of Engineering Structures Using Air Jet Pulses
(Konya Technical University, 2019) Hızarcı, Berkan; Kiral, Zeki
Research and development of structural response control systems are animportant area of interest for researchers. Under the different static anddynamic loads, it has become a necessity to use structural control systems inorder to reduce the vibration response of engineering structures. Seriousefforts have been made to transform the structural response control conceptinto a viable technology. Innovative active vibration control systems are neededto improve the structural dynamic behavior of structures used in differentoperating environments or operational processes. In this regard, the idea ofreducing the vibrations of structures using air jet pulses remains to beinvestigated and implemented. In this study, the response patterns of the samplestructure and vibration control via air jet pulses under harmonic baseexcitation were examined. Harmonic base excitation was given around the firstnatural frequency at which the structure has the highest displacement.State-feedback control method was used for vibration control of the structure.The forces required for vibration control of the sample structure were calculated.In addition, with the help of Matlab Simscape Multibody, physical modeling ofthe system and visualization of the vibration were provided. The results werecompared and it was observed that the vibration of the structure can be dampedvia proposed system. Finally, the nozzle design was conducted to providecontrol forces with air jet impulses to the system.
An Analysis According To Regulation of Dbybhy 2007 and Tbdy 2018 by Equivalent Earthquake Load Method of a Reinforced Concrete Building
(Konya Technical University, 2021) Döndüren, Mahmud Sami; Hava, Şeyda; Ecemiş, Ali Serdar
Turkey is located at high-risk seismic region. As a result of earthquakes happened in our country, loss of life and property were encountered. For this reason seismic standarts and design codes were prepared. These standards have been revised depending to technological development and increment in seismic know-how during time. The last seismic code; Turkish Building Seismic Code 2018; was published in official gazette at 18 March 2018 and come into force at 01 January 2019.In this study; the differences and similarities between 2007 and 2018 Turkish Seismic Codes were compared. In the first part of the study seismic damages were investigated, afterwards the 2007-2018 codes were compared according to Equivalent Lateral Earthquake Load method and numerical comparisons were made on selected analysis building models. In accordance with this purpose a sample analysis building model having framed and wall-framed structural system with / without basement were selected at two locations (Konya and İstanbul) and at two soil classes ( Z1-ZA and Z3-ZD) and analysed. The analysis results were compared. As a result, TBDY 2018 concluded an increase in floor displacements and a decrease in floor shearing forces.
Analysis of the Effect of Physical Properties of Drug Co-Crystals on Dissolution Concentration
(Konya Technical University, 2021) Elmas, Sinem; Genceli Güner, Fatma Elif
Psoriasis is an itchy and non-contagious skin disease. Its treatment method varies according to the severity of the disease. In oral treatments used in heavy stages, dissolution behavior is a vital characterization parameter for evaluating cocrystal, understanding dissolution mechanism, and predicting bioavailability of the drug. In this study, dissolution of cocrystals used in psoriasis was investigated. Effect of (i) different shapes, (ii) sizes, and (iii) grinding of cocrystals on the dissolution were considered with ultraviolet-visible (UV/Vis) spectroscopy. Results show that different physical properties and grinding can significantly increase the dissolution of cocrystals.
Applicability of Command Shaping Techniques To the Pulse Width Modulation Driven Systems
(Konya Technical University, 2019) Taşkın, Çağın; Kiliç, Ali; Kapucu, Sadettin
In this study, analternative input shaping method is proposed to reduce residual vibration tothe pulse width modulation delivered flexible systems. An input shaping methodis proposed which works robust even system parameters such as system naturalfrequency and damping ratio are not known or wrongly estimated. It is possibleto generate unity magnitude input shaper with high number of pulses within thismethod. This input shaper can eliminate or reduce residual vibration. Timelocations have an importance on performance of input shaping techniques. Timelocations of impulses are found by intersection points of reference motionprofile and triangle wave. This proposed method is compared with well-knownzero vibration method, performance characteristics of proposed input shapingtechnique and diagrams about the system response are demonstrated. Furthermore,it’s shown that proposed input shaping method works robustly even travellingtime is reduced.
Batch Ordering Inventory Management Under the Mixed Demand Information: a Case Study
(Konya Technical University, 2020) Alim, Muzaffer; Beullens, Patrick
This study is concerned with analysing the past demand data and development of aninventory model with demand arising from deterministic which is known in advance and random sourcessimultaneously. Two different shortages are created for each demand type and in order to prevent modelto backlog the deterministic demand, very high shortage cost is given for deterministic demand. Thenumerical value of the parameters are obtained from a real case which the inventory system of aninformation and technological organization of a university. The main difference of this study from theprevious studies is that the order amount must be in palette quantity for a deterministic and stochasticdemand inventory problem. Under this constraint, an inventory model is developed and tested withseveral datasets. Assuming lead time as constant, the value of deterministic demand present in the systemand impact of palette constraint are investigated. These investigations are compared with the status quoin the case study. It has seen that the palette quantity behaves as safety stock for high level randomdemand. Recommendations based on the impacts of advance demand information, lead time and palletquantity are presented in terms of changing in ordering costs, holding costs and service level.
Boron Removal From Industrial Wastewater With a Pva/ Amberlite Ira 743 Hybrid Membrane
(Konya Technical University, 2021) Özekmekçi, Mehtap; Ünlü, Derya; Çopur, Mehmet
In this study, the removal of boron from industrial wastewater was investigated by the pervaporation process. Pristine PVA and Amberlite IRA 743 doped PVA membranes have been prepared for this process. In the SEM analysis, while the dense and homogeneous structure was observed in pristine membranes, Amberlite IRA 743 distributions in doped membrane were seen clearly. The changes in the chemical bond structure of the membrane that is caused by the addition of Amberlite IRA 743 and cross-linking were determined by Fourier transform infrared (FTIR). While the affinity of the membranes on water was determined by the swelling test, the surface hydrophilicity was investigated by contact angle measurements. The effects of temperature and Amberlite IRA 743 amount were investigated on separation performance. While the increase in temperature increased the water flux, it did not have a significant effect on boron removal. While the water flux decreased, the boron removal increased with the increase of Amberlite IRA 743 amount. It has been determined that PVA Amberlite IRA 743 membranes show high separation performance in boron removal from industrial wastewater and more than 99% boron is removed.
Carstic Geopark Tourism in the World and Geopark Suggestion Area: Karapınar (konya- Turkey)
(Konya Technical University, 2020) Öztürk, Alican; Horasan, Bilgehan Yabgu
Jeopark kavramının temelleri Dünya da ilk olarak 17. Yüzyıla kadar dayanmaktadır. Ülkemiz ise jeopark kavramı ile 1970 yıllarında tanışmıştır. Oluşumu milyonlarca yıl alabilen jeolojik yapıların korunması ve sonraki nesillere aktarılması, hızla küreselleşen Dünyada önem kazanmıştır. Özelikle doğa turizmine meraklı insanların ilgisini çeken, özel jeolojik yapıları görmek ve gezmek isteyen insanların artan ilgisi nedeni ile jeopark turizmi Dünyada yaygınlaşmıştır. UNESCO listesinde Dünyada 147 adet jeopark mevcut olup, ülkemizde ise bu listeye girmeye hak kazanan Kula jeopark alanı bulunmaktadır. Karstik alanların jeoturizminde cezbedicili yanında, insanların karst yapılarına olan ilgileri, karstik yapıların meydana getirdiği jeopark alanlarının önemini artırmaktadır. Karapınar potansiyel jeopark alanı, Orta Anadolu’da, Konya idari sınırları içerisinde ve merkeze yaklaşık 100 km uzaklıktadır. Karapınar ilçe merkezinin hemen doğusunda, yaklaşık 1500 km² lik bir alanı kapsayan jeolojik miras alanı, bu alan etrafındaki jeositler, arkeolojik ve kültürel sit alanları olarak değerlendirilmektedir. Bölgede, muhtelif boy ve ebatlarda, sulu veya susuz 20 den fazla sayıda obruk bulunmaktadır. Jeopark öneri alanında bulunan, halk arasında nazar boncuğu olarak ta adlandırılan Meke gölü, Karapınar- Ereğli yolu üzerinde yaklaşık 7. km’de, ana asfaltın yaklaşık 1.5 km kuzey batısında kalmaktadır. Jeolojik terim kavramıyla Meke Maarı olarak tanımlanan Meke Gölü, Pleyistosen’den itibaren iki aşamalı volkanik aktivite ile sönmüş bir volkan kraterinin suyla dolmasıyla oluşan ve ortasında adacıklar bulunan bir krater gölüdür. Diğer bir göl olan Acıgöl ise, Karapınar Ereğli yolu üzerinde 5. Kilometrede gözlenen ve anayolla yaklaşık 500 metre mesafede yer alan sığ krater gölü görünümündeki maar, volkan patlamasıyla meydana gelmiş çukurdan ibarettir.
Classification of Pneumonia Using Pre-Trained Deep Networks With Chest X-Ray Images
(Konya Technical University, 2021) Er, Mehmet Bilal
Pneumonia is a lung infection that can be caused by bacteria, viruses, or fungi. The infection causes the lungs to become inflamed and filled with fluid or pus. It can be a serious and life-threatening disease. Many people die every year due to pneumonia worldwide. Early detection and treatment of pneumonia can significantly reduce mortality. For this reason, this research is to propose a method based on pre-trained deep network models using x-ray images to detect pneumonia. Various pre-trained Convolutional Neural Networks were used as feature extractors to classify chest x-ray images into two classes without pneumonia and pneumonia. AlexNet, VGG16, ResNet (ResNet18, ResNet50, ResNet101) models are preferred as pre-trained deep network models. The hybrid feature vector is obtained by combining the features obtained from these models. As the classifier, Support Vector Machines (SVM) and Softmax in the last layer of deep networks are used. Experiments are carried out on the data set commonly used in the literature. The highest classification success is obtained from the hybrid feature vector as 98.32%.
Cluster-First Route-Second Approach for the Solution of Vehicle Routing Problem With Soft Time Windows; a Supermarket Chain Application
(Konya Technical University, 2020) Ercan Cömert, Serap; Yazgan, Harun Reşit; Çakir, Büşra; Sari, Nazan
The vehicle routing problem with soft time windows is a type of vehicle routing problem with time windows which allow to serve customers outside their time windows, but the penalty costs is applied for the company for early or late service. In this study, an approach consisted of two stages as "cluster-first route-second” is proposed for the vehicle routing problem with soft time windows. Firstly, customers are clustered according to K-Means and K-Medoids clustering algorithms, then routed by the help of mixed integer linear programming model. Finally, the ANOVA test is used to show the effectiveness of the algorithms and the experimental results showed that the results obtained with the algorithms provides a better solution than the actual costs of the firm.
Co2 Capture Using Polyethyleneimine Functionalized Silica Xerogels
(Konya Technical University, 2021) Kaya Güzel, Gülcihan; Deveci, Hüseyin
CO2 capture technologies using solid adsorbents are promising approach to reduce environmental pollution resulting from CO2 emission. In this study, silica xerogel derived from cheap precursor was used as a CO2 adsorbent after polyethyleneimine (PEI) functionalization. Fourier transform infrared (FTIR) analyses indicated that PEI functionalized silica xerogels were successfully prepared. N2 adsorption-desorption isotherms revealed that PEI loading decreased specific surface area and pore volume of the neat silica xerogel in contrast to pore size. An increase in particle size of the neat silica xerogel was observed in the case of PEI loading. Positively surface charged silica xerogels were obtained with PEI loading of the neat silica xerogel which had negatively charged surface. CO2 adsorption measurements showed that CO2 adsorption capacity of the neat silica xerogel (0.98 mmol g-1) significantly increased with increasing PEI loading (30 – 70 wt%). At optimum PEI loading (50 wt%), CO2 adsorption capacity of silica xerogel was determined as 1.94 mmol g-1. After 5 adsorption-desorption cycles, PEI functionalized silica xerogels still exhibited high CO2 adsorption capacity. The hopeful results showed that PEI functionalized silica xerogels can be used as an adsorbent with a good CO2 adsorption performance and stability.
Colorimetric Detection of Hydrogen Peroxide With Cellulose Nanocrystals Obtained From Waste Paper/ Silver Nanoparticles Nanocomposite Sensor
(Konya Technical University, 2021) Uzunoğlu, Deniz; Özer, Ayla
This study includes the results of the studies of the production of cellulose nanocrystals (CNC) from waste paper by the acid hydrolysis method, the synthesis of nanocomposite material CNC/AgNPs as a result of mixing the produced CNC and AgNO3 solution and then reducing the Ag+ ions to Ag0 by adding NaBH4 to the medium, the characterization of CNC/AgNPs by UV-vis spectroscopy, DLS, SEM, EDX and XRD methods, and its usability as a sensor in the colorimetric detection of H2O2. For the quantitative analysis of H2O2 with CNC/AgNPs nanocomposite, a calibration line was created in the range of 0.001-1.0 mM H2O2 concentration, and the minimum detection limit for H2O2 of CNC/AgNPs was determined as 0.7864 ?M. In order to determine the selectivity of CNC/AgNPs to H2O2, the studies of the colorimetric detection of H2O2 with CNC/AgNPs was carried out in the presence of various components; it was concluded that CNC/AgNPs can be used effectively in the colorimetric detection of H2O2 in the presence of KCl, Al(NO3)3, oxalic acid, lactic acid, glucose, lactose, maltose, fructose, sucrose, urea components.
Comparative Performance Analysis of Combined Power Systems Trilateral Cycle-Organic Rankine Cycle (tlc-Orc) and Organic Rankine Cycle Organic Rankine Cycle (orc-Orc)
(Konya Technical University, 2021) Bilir Sağ, Nagihan; Özçelik, Mehmet
One of the most widely used to generate power using heat energy or waste heat energy from renewable energy sources is the Organic Rankine cycle. The Trilateral Cycle differs from the Organic Rankine cycle in that it uses an expander instead of a turbine element. In this study, the structures of Trilateral cycle - Organic Rankine cycle and Organic Rankine cycle - Organic Rankine cycle combined power systems were examined and thermodynamic analyzes were made with the help of Engineering Equation Solver (EES) program. For each combined power system, the fluid pairs that maximize the system performance at different temperatures of the geothermal source and sub-cycle evaporator were determined and the results of the combined power systems using these determined fluid pairs were compared. According to the results of the research, it was determined that there are pairs of fluids that maximize the thermal efficiency and / or the net power obtained from the system for each operating condition. It was determined that at temperatures of 100-280 oC of the geothermal resource, the combined power system was evaporating hot, which maximized the net power. Depending on the working conditions, it was determined that the net power output of ORC-ORC was up to until 23.5 % higher than TLC-ORC.
Comparison of Derating in Transformerunder Non-Linear Load and Imbalanced Supply Voltage Based on Tsfem
(Konya Technical University, 2020) Najafi, Atabak
Distribution transformers which are widely used in industry and distribution centers are themost affected by voltage imbalance and harmonic loads. These situations have a negative impact onefficiency , core loss and winding loss of distribution transformers, In this article, derating as well as lossesincrease of transformer under non-linear loads and imbalanced supply voltage conditions are examined .harmonic loss factor (HFL) and K-factor have been used to perform the transformer derating. In this study,3D time-step finite element method(TSFEM) used to observe the magnetic flux density formed in thewindings and core of the distribution transformer. According to the results obtained, it is seen that theIEEE standard is insufficient for the derating of the transformer under high harmonic current (THDI) andunbalanced conditions and Time Stepping Finite Element Method is a more suitable method.
Comparison of Energies Absorbed at Different Speeds of Polymer Materials Used in Vehicle Bumpers
(Konya Technical University, 2021) Şimşir, Ercan; Yavuz, İbrahim; Erik, Mustafa Çağdaş
Today, developments in the automotive field have brought vehicle safety to the fore with the increase in the number of vehicles. The automotive sector focuses on the development of cars with high safety levels, low fuel consumption and low cost production methods. In order to realize these situations, the appropriate design will be created by the use of materials that are lightweight and have good impact absorption. The use of polymer materials in the vehicle is widely used in the front bumper of the vehicle, as in every region. In this study, the impact absorption rates of the polymer materials used in two different front bumpers were investigated. Samples from the front bumpers belonging to the vehicles in accordance with the ASTM-D-7136 standard were tested and their data were evaluated. Vehicle front bumper tests were conducted at speeds of 3 m / sec, 5 m / sec and 10 m / sec. Energy-strain, stress-displacement and velocity-time graphs were created with the data obtained. In the tests, it was seen that the front bumper material of the H vehicle has better impact absorption ability at different speeds than the front bumper material of the F vehicle.In this study, the impact absorption rates of the polymer materials used in two different front bumpers were investigated. Samples from the front bumpers belonging to the vehicles in accordance with the ASTM-D-7136 standard were tested and their data were evaluated. Vehicle front bumper tests were conducted at speeds of 3 m / sec, 5 m / sec and 10 m / sec. Energy-strain, stress-displacement and velocity-time graphs were created with the data obtained. In the tests, it was seen that the front bumper material of the H vehicle has better impact absorption ability at different speeds than the front bumper material of the F vehicle.
Comparison of Flight Performances of Unmanned Air Vehicle With Six Rotors and Eight Rotors Under Different Disturbance Effects
(Konya Technical University, 2020) Yıldırım, Şahin; Çabuk, Nihat; Bakircioğlu, Veli
In this study, six-rotors and eight-rotors unmanned aerial vehicles have been comparedunder disruptive effect. To determine the effect of the difference of rotor number on the flight performance,the same controller was used in both types of vehicles. Proportional-Integral-Derivative control method,which is one of the traditional control methods, was used and control parameters were determined byobservational study. A comparison of these two air vehicles was made by taking into account the errorstrajectory tracking for three axes. The comparison results are presented numerically. According to theresults, it was observed that the UAV with eight rotors allowed a more stable flight as the disturbanceeffect increased compared to the UAV with six rotors.
Concept Design of an Aluminum One-Piece Driveshaft for Pick-Up Truck Applications
(Konya Technical University, 2021) Kasaba, Muzaffer; Işık, Efe; Tarakçi, Sedat
Driveshafts are the driveline elements that transfers torque and rotational motion which is received from the engine to the rear axles. In order to meet the high torque handling requirements, driveshaft components are usually made up of steel. Weight reduction in steel parts can often be limited due to the boundary conditions of geometries. For this reason, applications developed with low density parts such as aluminum gain importance. Within the scope of this study, engineering calculations for aluminum cardan shaft for pick-up style light commercial vehicle applications were performed and the calculations were verified with finite element analysis. As a result of the corrections, deviation of 1% for strength calculations and 8% for natural frequency calculations was calculated between the two methods, and it was determined that the deviation values were acceptable. The yield limits and safety coefficients of the aluminum material used were calculated for the unit parts with the results obtained with finite elements. It has been determined that the safety coefficients obtained are suitable for driveshafts.
A Cost-Driven Mathematical Model and Heuristic Approach for Parallel Assembly Lines With Heterogeneous Workforce
(Konya Technical University, 2020) Kökhan, Serhan; Baykoç, Ömer Faruk; İşleyen, Selçuk Kürşat
With the developing technologies, it has become possible for people, machines and robotsto work collaboratively in production environments. In particular, the collaborative working model hascreated an opportunity to evaluate the concept of Industry 4.0 which is the popular title of recent yearsand assembly line problem structures under the same roof. In this study, as a part of this development, amathematical model which combines parallel assembly line problems and human and robot collaborativeworkforce which is an important parameter of Industry 4.0 philosophy is proposed. The mathematicalmodel was tested for new data sets derived from existing data sets in the parallel assembly lines literatureand the results were analyzed. Then, the same data sets were solved with a different method calledRandom Search Method and the results were compared and analyzed. Since there are very few studieswith heterogeneous workforce in Parallel Assembly Line Balancing Problems (PMHDP), it is thought thatthis study will provide a new perspective for the assembly lines which are thought to be established underthe concept of industry 4.0.
Design and Construction of a Folding Mechanism for a Two–antenna Radar System
(Konya Technical University, 2019) Yurt, Hünkar Kemal; Turgut, Ali Emre; Söylemez, Eres; Güler, İsmail; Firtinaoğlu, Ekrem
In this study, afolding mechanism having 1 degree of freedom is designed and constructed for atwo-antenna radar system. The optimum mechanism for the problem is selectedsystematically among the conceptual mechanism alternatives. Then, a detailedsynthesis and analysis study are performed on the selected mechanism, and themechanism is implemented on the radar system. By performing modal and strengthanalyses on the 3D model of the folding mechanism, the design is improved andfinalized according to the system requirements.
Detailed Channel/Lob Analysis of a 2d and 3d Hybrid Video Using Eeg Signal
(Konya Technical University, 2021) Manshouri, Negin; Melek, Mesut; Kayikçioğlu, Temel
It is important to evaluate sudden transition and steady-states in video analysis consisting of 2 dimensional (2D) and 3D tracks, regarding the human eye structure. In this study, the power spectrum density (PSD) of the human brain signals was taken into consideration for analysis as a result of a 2D and 3D hybrid video watching. We claimed in our previous studies that people lose their depth perception when they get tired. In this study, a single stream anaglyph video consisting of random 2D and 3D tracks is provided. In 2D and 3D hybrid video study, PSD based on short-time Fourier transform (STFT) and visual representation called spectrogram were used in brain signal analysis. After all EEG frequency bands have been tested, the delta band has been chosen as the dominant band, taking into account the difference of PSD in the comparison of 2D and 3D parts in the spectrogram chart. Extracted features from this band were classified by two popular classifiers. These are support vector machine (SVM) and Linear discriminant analysis (LDA) algorithms. Consequently, the frontal and temporal lobes show better results in the classification of 2D and 3D transitions than other lobes. As a result of statistical functions and Hjorth parameters used as feature extraction methods, classification success for SVM and LDA algorithms was computed as 68 % and 79 %, respectively.
Determination of Lqr Controller Parameters for Flexible Link Manipulator System Using Metaheuristic Algorithms
(Konya Technical University, 2021) Özkaya, Semih; Conker, Çağlar; Bilgiç, Hasan Hüseyin
The presented study provides detailed analysis of the LQR controller design for motion control of a flexible link manipulator system with the optimization of control parameters. The main objective of proposed optimization ensures that the flexible link manipulator system reaches the desired angular position as soon as possible and eliminates tip deflections. The Vibrating Particle System algorithm used for the first time in the adjustment of LQR weight matrices with this study. The efficiency of the proposed approach has been showing by comparing it with well-known optimization algorithms such as Genetic Algorithm and Artificial Bee Colony. Also, multi-objective function is proposed that considers the important parameters of the control response for flexible link manipulator systems in this study. Parameters of optimization algorithms have been determined by searching a wide search space and each algorithm was examined in terms of four different population values in order to reach results for 100 iterations. Furthermore, the configurations that obtained the best control results for optimization algorithms are compared with each other according to the theoretical and experimental studies performed. The article is organized in a manner that presents the required theoretical background and the implementation-related details for each of the optimization algorithms introduced.

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