Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji

https://dergipark.org.tr/en/pub/gujsc

List of Papers (Total 857)

Investigation of the Effect of Using Fe + Pure Water Nano Fluid on Thermal Performance in a Two Phase Closed Thermosiphon

Heat is a type of energy that is used in many applications and can be easily converted into other types of energy. In this study, a performance analysis was carried out by using Fe + Pure water nano fluid in place of pure water in a two phase closed thermosiphon, which has a wide place in practice due to its simple structure. In the study, a copper thermosiphon with a length of 1...

Student Modelling on Language Teaching Based on Bayesian Networks

Acquiring a reliable student model is the principal task of an Intelligent Tutoring System (ITS). A precisely defined student model is also the key term for the success of ITSs. In this paper, a study on inferring the accurate student model on language learning is offered by utilizing artificial intelligence. In addition to the general structure of an ITS, a probabilistic model...

The Effects of Cutting Parameters on the Kerf and Surface Roughness on the Electrode in Electro Erosion Process

In this study, electrode wear caused by machining from cold work tool steel with heat treated 60-62 HRC hardness was investigated by using electro erosion method and Cupro MAX CuCrZr electrode. The workpiece and electrode material are eroded by melting and evaporation as a result of the electrical arc (sparking) that occurs between the electrode and the workpiece in the...

Design and Implementation of an Analog Controller Based on K-factor Design Method for a Novel Isolated Z-Source DC-DC Converter with High Voltage Gain

In this study, an analog control circuit design and implementation are performed by using the K-factor design method for a novel isolated Z-source dc-dc converter with high voltage gain. The closed loop system created by the control circuit ensures a constant output voltage at the converter output although there is a step change in input voltage and load within certain limits...

Efficiency and Performance Comparison Between Synchronous Reluctance and Induction Motor in Axial Flux Concept

In this study, the Axial Flux Synchronous Reluctance Motor (AF-SynRM) with multiple barriers in its rotor is designed and it is aimed to compare the performance with the Axial Flux Induction Motor (AF-IM) with the same stator structure and dimensions. For an equal comparison, the motor dimensions and stator structure are chosen the same, only the rotor is changed. In the...

Comparison of Control Techniques for Series Resonant Converter

There are many different derivatives of the variable and fixed frequency switching control techniques used in the control of load resonant converters. In this study; among these techniques frequency modulation (FM), phase shift modulation (PSM) and pulse density modulation (PDM) are applied separately to series resonant converter (SRC). The techniques are examined and compared in...

Free Vibration Analysis of a Functionally Graded Micro-Beam with Tapered Cross Section

In this study, the free vibration analysis of a functionally graded (FG) micro-beam with tapered cross-section is carried out theoretically. The beam has material distribution according to the power law throughout the thickness. The governing equation is reduced to an ordinary differential equation for the tapered beam with a cross-sectional geometry whose width varies...

Investigation of the Relationship Between Power Consumption and Noise Level During Hard Turning of CBN Tools and DIN 1.2367 Steel

In this study, hard turning tests were carried out under dry cutting conditions on hardened DIN 1.2367 (55 HRC) steel material. The effect of the cutting parameter (three different cutting speeds, three feed rates and three cutting depths) on the power consumption and sound level values was investigated. A mathematical model has been created to estimate the power consumption and...

An Investigation for the Potential of Biogas to be Produced from Animal Waste in Corum

One of the most important current issues is obtaining and efficiently using energy, a basic necessity of life. With the continuous development of technology and increase in the world population, energy demands keep increasing. In general, the global energy production needs are met with fossil-sourced fuels. However, due to the fact that fossil fuels will be exhausted over time...

Investigation of the Effect of Temperature on the Structural and Magnetic Properties of MgB2 Superconductor Produced Using Boron Doped with Carbon by CVD Method

Carbon, which is known to play a improvement role on the superconductivity properties of MgB2, was doped into MgB2 by CVD (chemical vapor deposition) method, and the change of structural and magnetic properties observed in MgB2 in relation to the change of sintering temperature was investigated. In this context, in the sample preparation step, amorphous nano boron powders with...

A Comparison of Two Discrimination Spectrometers

Two spectrometers were examined for the discrimination of the low-energy part of the 137Cs gamma-ray spectrum. Obtained spectra from the spectrometers were compared with each other. To perform an exact comparison, partial and complete discrimination processes were realized.

Developing of a Virtual MCA to Acquire a Radiation Spectrum

A virtual MCA (Multichannel Analyzer) was developed via a software in the computer environment to display a spectrum for radiation detection experiments. A pulse generator that substitutes for a particle detector was used to supply the signals to be analyzed in the MCA. The pulses from the generator were analyzed by a virtual MCA and a real MCA. Channel numbers and the number of...

Detection of SSL/TLS Implementation Errors in Android Applications

Security Socket Layer (SSL) / Transport Layer Security (TLS) protocols are utilized to secure network communication (e.g., transmitting user data). Failing to properly implement SSL/TLS configuration during the app development results in security risks. The weak implementations include trusting all host names, trusting all certificates, ignoring certificate verification errors...

Investigation of the Standard Deviation of Ornstein - Uhlenbeck Noise in the DDPG Algorithm

Reinforcement learning is a learning method that many creatures often unwittingly use to gain abilities such as eating and walking. Inspired by this learning method, machine learning researchers have reduced this learning method to subheadings as value learning and policy learning. In this study, the noise standard deviation of the deep deterministic policy gradient (DDPG) method...

Estimation of Large Household Appliances Stock in the Residential Sector and Forecasting of Stock Electricity Consumption: Ex-Post and Ex-Ante Analyses

Energy efficiency offers a wide variety of opportunities that will provide efficient resource utilization, alleviate the pressure of energy costs on the economy and reduce foreign energy dependency, and support in combating the harmful effects of climate change. This paper aims to develop necessary data sets to guide policymakers in their decision-making process to identify...

Application Development on Gas Station and Consumers with the Representational State Transfer Approach

Although Turkey is close to countries with rich oil deposits, it is among the countries that use expensive fuel oil. This situation forces consumers to save on fuel expenditures. On the other hand, the high number of fuel stations and the variety of fuel products cause fuel stations to offer different services and prices in a competitive environment. This change in the services...

Determining the Preferences of Office Workers Regarding the Seating Element They Use

The human body should be comfortable in all actions required by the working environment. Otherwise, it will occured such as fatigue, decreased job comfort, low productivity. This situation is an important problem especially for individuals such as office staff who work in the same position for a long time. In this study, it was conducted to determine the office employees...

Yumurta Kabuğu Görüntülerinde Kırık Tespiti İçin Daha Hızlı Bölgesel Tabanlı Çok Katmanlı Evrişimsel Sinir Ağları

Automatic detection of cracked eggs is of great importance in terms of health. Today, the separation of cracked eggs is done by experts through observation. This process causes time loss and erroneous detections together with tiring. In this direction, a system based on Region-based Convolutional Neural Networks has been designed for the automatic detection of cracked egg surface...

Stokiyometri Oranının İki Hücreli PEM Yakıt Hücresi Yığını Performansına Etkisinin İncelenmesi

Buhar enerjisinin sanayide kullanılmaya başlanmasıyla beraber fosil yakıtların önemi artmıştır. Fakat özellikle son günlerde küresel ısınma sorunu dünyada ciddi olarak hissedilmektedir. Bu sorunun en önemli sebebi de fosil yakıtların yakılmasıyla açığa çıkan zararlı emisyonlardır. Dünya bu sorunu ortadan kaldırmak amacıyla çeşitli alternatif enerji kaynaklarına yönelmiştir. Son...

Çocuklara Yönelik Ayran Ambalajının Yeniden Tasarımı

Packaging design has a very important position for companies in today's consumption age. Packages exhibited together on the shelves in a determined order are representatives of companies that compete with each other. These products cannot fulfill their duty unless they reach the right target audience. For this reason, determining the target audience and presenting designs for it...

Selecting and Analyzing Appropriate Probability Distributions for Reliability of Electrical Transmission Lines

Reliability is the ability of a system or system components to function within a specified time under specified conditions. One of the most important criteria of electricity transmission systems is to be able to keep the energy on the system continuously within the limits and to be interrupted for the least possible time. The reliability study offers important advantages such as...

Analysis the Effects of Electric Vehicles on Distribution Networks with Simulations Based on Probabilistic Methods

Elektrikli araçların (EA) sayısı arttıkça, EA’ların şarj yükünün güç dağıtım şebekelerine ilave yük bindireceği ve sorunlar yaşanabileceği güncel tartışılan bir konudur. EA’ların şarj maliyetini şebekenin yükünün düşük olduğu saatlere kaydırmaya yönelik akıllı mekanizmalar bir çözüm olarak değerlendirilmektedir. Bu çalışmada, EA’ların şebekeye entegrasyonu sonrası bu tür ihtiya...

Pool Boiling Heat Transfer Properties of Water-Based Dilute Fe+ZnO Hybrid Nanofluid under Low Heat Flux Condition: A Numerical Study

Thermophysical properties of the working fluid of a fluid-driven heat transfer system is the key parameter in determination of heat transfer performance of the system they were used. The nanofluids, nanoparticles containing colloidal suspensions, have been extensively used for performance enhancement in many applications, however, the nanoparticles cannot have both high thermal...

Traffic Classification and Comparative Analysis with Machine Learning Algorithms in Software Defined Networks

In computer networks, diverse applications generate network traffic with different characteristics. Network traffic classification is significant to manage networks better, improve service quality and ensure security. Software-Defined Networks (SDN) provides flexible and adaptable techniques for traffic classification with its programmable structure. SDN flows naturally exhibit...

9-Seviyeli Paket E-Hücreli Eviriciler için Üstün Burulma Algoritması Tabanlı Kayan Kipli Kontrol Tasarımı

In this paper, a super twisting algorithm based sliding mode control method is presented for 9-Level Packed E-Cell inverters. Regulating the load voltage is the main objective in the control of off-grid inverters. To achieve this objective firstly, a sliding mode controller is designed. The output of the sliding mode method contains chattering which causes variable switching...