The electric field optimization minimizing the field strength on an electrode surface and providing its uniformity is important in designing high voltage power transformer bushings and other apparatus from the viewpoint of efficient utilization of the electric field space. The high voltage power transformer bushing with cylinder electrode system has been designed and tested in this investigation. It was found that the insulation method of the cylinder electrode was the most important factor to lower streamer initiation voltage. The optimized design uses both internal and external elements for electric stress grading at critical parts of the bushing. Applying optimization theory based on charge simulation method, the author developed a computation program for electric field automatic optimization in 3D dielectric axisymmetric field. The results of the computation realized some excellent electrode profiles with uniform electric field distribution. Moreover, the discrepancy from the electric field uniformity on 3D dimensional profile caused by applying it to an axisymmetric electrode was discussed. Then a new electrode with uniform field distribution was obtained by using the computation program for optimization.

The electric field optimization minimizing the field strength on an electrode surface and providing its uniformity is important in designing high voltage power transformer bushings and other apparatus from the viewpoint of efficient utilization of the electric field space. The high voltage power transformer bushing with cylinder electrode system has been designed and tested in this investigation. It was found that the insulation method of the cylinder electrode was the most important factor to lower streamer initiation voltage. The optimized design uses both internal and external elements for electric stress grading at critical parts of the bushing. Applying optimization theory based on charge simulation method, the author developed a computation program for electric field automatic optimization in 3D dielectric axisymmetric field. The results of the computation realized some excellent electrode profiles with uniform electric field distribution. Moreover, the discrepancy from the electric field uniformity on 3D dimensional profile caused by applying it to an axisymmetric electrode was discussed. Then a new electrode with uniform field distribution was obtained by using the computation program for optimization.

In this study, the electrical and thermal efficiency of the natural convection water-cooled photovoltaic panel (PV) is compared with the standard PV module. PV modules are made up of polycrystalline solar cells. As it is known that, an increase in PV panel temperature results in a decrease in electrical efficiency. The aim of this study is to increase PV panel electrical efficiency. PV panel characteristic values such as air/PV panel temperature, solar radiation, voltage, current, and power are recorded for both panels to the computer simultaneously. The thermal and electrical energy performance of PV panels are analyzed comparatively. The results are presented in detail. The water circulation structure is mounted under the PV module by using a glue that has good heat conductivity. The structure contains an S-shaped pipe and a plate made of copper. The plate is used for better heat absorption from the PV panel which is mounted downside of the panel with glue. The efficiency of the PV module with having a proposed cooling system and normal PV module is analyzed. For the overall efficiency, it is observed that the water-cooled PV system is better than the standard PV module by % 6.2.

Nowadays, working on digital images is gaining much popularity in multimedia systems, due to the rapid increase in the utilization of large image databases. Thus, the Content-Based Image Retrieval (CBIR) method has become the most valuable method for these databases. This study mainly focuses on content-based image retrieval; which uses image features like color, shape, texture, etc. by searching the user query image from a large image database based on user request. CBIR is the most widely used technique as its searching capability is faster than the other traditional methods, and it works well in retrieving images automatically. It is also a big alternative approach to traditional methods. The CBIR techniques are used in many applications like surveillance detection, crime avoidance, fingerprint identification, E-library, medical, historical monument and biodiversity information systems, and many more. A total of 38 CBIR articles were comparatively analyzed.

In this study, the electrical and thermal efficiency of the natural convection water-cooled photovoltaic panel (PV) is compared with the standard PV module. PV modules are made up of polycrystalline solar cells. As it is known that, an increase in PV panel temperature results in a decrease in electrical efficiency. The aim of this study is to increase PV panel electrical efficiency. PV panel characteristic values such as air/PV panel temperature, solar radiation, voltage, current, and power are recorded for both panels to the computer simultaneously. The thermal and electrical energy performance of PV panels are analyzed comparatively. The results are presented in detail. The water circulation structure is mounted under the PV module by using a glue that has good heat conductivity. The structure contains an S-shaped pipe and a plate made of copper. The plate is used for better heat absorption from the PV panel which is mounted downside of the panel with glue. The efficiency of the PV module with having a proposed cooling system and normal PV module is analyzed. For the overall efficiency, it is observed that the water-cooled PV system is better than the standard PV module by % 6.2.

Aperture averaged scintillation of four petal Gaussian beam is studied in this article. Split step propagation approach which is used in wave propagation applications is selected to model atmospheric turbulence. Results are plotted in two types. First type is the analysis of aperture averaged scintillation versus propagation distance for constant receiver aperture. Second ones involve scintillation performance applying aperture averaging at constant distance. All results are compared with Gauss beam since commercial lasers generally radiates in Gaussian distribution. We observe that four petal Gaussian beam becomes more advantageous under moderate turbulence than weak one. In other point of view, it is possible to obtain less scintillation index by increasing beam order. Our results are applicable optical applications operating in atmosphere.

In this study, Silicon Dioxide (SiO2) thin films processed by the spin coating method was studied with prepared solutions. Antireflection coating effect of deposited SiO2 thin films on crystalline silicon substrates was analyzed after optimizing the solution, deposition, and thermal treatment processes. The effect of ethanol dilution of the solution was investigated as well. Spectrophotometer reflectance measurements, Scanning Electron Microscopy (SEM) measurements and Afors-het based simulations were carried out. For the prepared solution based SiO2 thin films, the annealing temperature of 950 °C for 7 min in the air was determined as optimum. The minimum surface reflectance of SiO2 coated silicon surface could be reduced below 10% depending on the applied process. Based on the silicon solar cell device simulations, it was revealed that efficiency of a solar cell could be improved 4.23% more thanks to the antireflection coating effect.

In this study, it is aimed to eliminate the harmonics selected by the selective harmonic elimination (SHE) method in a 7-level cascade multilevel inverter using artificial neural networks (ANNs). A control algorithm has been developed in which the 3rd and 5th harmonics or 5th and 7th harmonics can be eliminated according to the selection while adjusting the output voltage amplitude of the inverter. The required switching angles for SHE are calculated in real time using ANN. These angles were first obtained offline training of ANN using Newton-Raphson method. ANN was trained in MATLAB® environment according to the obtained data. The resulting ANN algorithm and practical implementation using the STM32F429 ARM microcontroller® and inverter switching was provided. Experimental results of the system with RL load were tested.

Internet use has become increasingly widespread nowadays. In addition, there is a significant increase in the amount of text content produced in digital media. However, the accuracy and inaccuracy of the news we read and the content produced in a large number are also unknown. In this study, classification and analysis of whether the news is real or not were done by using Deep Learning methods. For the English news, the data set created by Katharine Jarmul was used. The data set contained a total of 6336 news items. The distribution of this data set, which consisted of political and political news, was 50% fake and 50% real. The method used in text classification was Term Frequency - Inverse Document Frequency (TF-IDF). The classification was made with the data set used and 93.88% success and 6.12% error were obtained as a result of the analysis.

Internet use has become increasingly widespread nowadays. In addition, there is a significant increase in the amount of text content produced in digital media. However, the accuracy and inaccuracy of the news we read and the content produced in a large number are also unknown. In this study, classification and analysis of whether the news is real or not were done by using Deep Learning methods. For the English news, the data set created by Katharine Jarmul was used. The data set contained a total of 6336 news items. The distribution of this data set, which consisted of political and political news, was 50% fake and 50% real. The method used in text classification was Term Frequency - Inverse Document Frequency (TF-IDF). The classification was made with the data set used and 93.88% success and 6.12% error were obtained as a result of the analysis.

Single-stranded DNA-binding (SSB) proteins play an important role in DNA metabolism involving DNA replication, recombination, and repair in all living beings. In molecular biology, SSB proteins are used as enhancers to increase the efficiency and specificity of PCR. Thermostable SSB protein eliminates secondary structure or dimer formation and significantly increase the effectiveness of amplification of DNA fragments. In this study, it was ensured that the SSB gene of thermophilic bacteria Thermus aquaticus (T. aquaticus) was cloned into the pET28b vector and expressed in E. coli BL21 (DE3) PLysE cells. Then, the purification of the SSB protein produced in E. coli BL21 (DE3) PLysE cells was performed. 20 mg SSB protein was obtained from 1L bacterial culture, and its purity was more than 90%. It was shown by the PCR experiment that the SSB protein produced in this study could increase the amplification efficiency.

In this study, it was aimed to develop an accurate forecasting model for the monthly electricity demand of Turkey in the medium-term. For this purpose, the Group Method of Data Handling (GMDH)-type Neural Network (NN) approach was used to structure a nonlinear time-series based forecasting model. A large dataset containing monthly electricity demand was considered for the period of 2003-2018. The developed model was tested in the period of 2019/01-2019/11 in order to determine the generalization ability of the model. The test results showed that the developed model was very close to actual values. The obtained test performances were 2.10 % for mean absolute percentage error (MAPE), 2.36 % for root mean square percentage error (RMSPE) and 0.869 for coefficient of determination (R2). In addition, results of the proposed GMDH-type NN model were compared with the forecasting results of a literature study. The comparison revealed that GMDH-type NN was a better approach for forecasting the monthly electricity demand of Turkey. Finally, the developed model was utilized to forecast monthly electricity demand in the period of 2019/12-2020/12.

Adjusting the dose of radiation which is received by a cancer patient during radiotherapy is very important. The use of dosimetric gels to calculate the applied dose distribution three- dimensionally is a current research topic in radiotherapy. In this study, 16 different Fricke gels including gluconic acid (GA) were produced. These gels were irradiated from 0 to 250 cGy with increments of 50 cGy. MR intensity values and images, UV absorbance values and FT-IR spectra of gels were obtained before and after the irradiation process. The UV absorbance and MR intensity values showed a linear increase in relation to the increase in the applied dose and the amount of ferrous sulfate and GA content in the gels. The oxidation of iron increases as a result of the interaction with hydrogen peroxide which is the product of the irradiation process and GA, and thus the response of the gel to the irradiation process becomes more effective.

Wear losses have a great importance in the world machinery industry. They cause billions of dollars in financial losses every year. Studies on surface treatments are increasing day by day in order to minimize the wear losses of materials. In this study, the pack boronizing process was applied to AISI 4140 and AISI H13 steels, which are frequently used in the manufacturing and molding industry, by using Ekabor II powder at 900 °C and 950 °C for 4 and 6 hours. Microstructural examinations of the samples subjected to metallographic processes were carried out. Afterwards, microhardness measurements were performed by applying 50 gf load for 10 seconds. Wear tests were carried out using pin-on-disk tribotests in a dry environment under 2 N and 5 N loads on the CSM Tribometer device. Wear losses were measured as volumetric loss. Thanks to the boronizing process, surface quality, surface hardness, and wear resistance of both steel materials were increased at a high rate.

In this study, a popular co-flow thrust vectoring system, which is superior to typical Coanda nozzles with one main jet, is examined experimentally and compared with 2D and 3D computational fluid dynamics results. High Speed Orienting Momentum with Enhanced Reversibility nozzle concept is the base design to proposed configuration which uses a control jet additional to the main jet for better and active enhancement on the flow vectoring and streamlined side-walls resulted in less flow blockage. This comparatively novel concept is utilized in an experimental setup to direct the thrust of aerial vehicles. The system includes two inlets (inlet1, inlet2) with different jet velocities and one pintle to separate and smoothly direct these jets and a converging-diverging nozzle to enclose these components. Experimental study is accomplished with four different configurations of inlet1 and inlet2 as 15 m/s and 10 m/s; 20 m/s and 10 m/s; 30 m/s and 10 m/s, and 45 m/s and 10 m/s, respectively. The tangential velocities on the curved surfaces are successfully measured utilizing a micro-manometer (Pitot tube) so that attachments/detachments of jets on the exit walls and deflection angles are calculated for each inlet velocities. The current experimental study also revealed that 3D assumption of computational fluid dynamics of Coanda effect is highly accurate and deflection angle results are not far from experimental results with the average deficit of only 5.44 %. As the result, 3D verification study resembles to experimental study in terms of deflection angles for all configurations.

Superalloys have become increasingly used in the machining sector due to their high strength, temperature and machinability. One of these alloys, Nilo (Invar) 36, has a low thermal expansion and its use is rapidly increasing in areas where high temperature and expansion are not required, especially in composite mould applications, such as aerospace, electronics, measuring instruments and aerospace. In this study, a mathematical model based on artificial intelligence and an interactive visual interface in MATLAB software were developed according to the test results obtained from surface roughness Ra, cutting methods, rotational speeds, cooling method and cutting speed of Nilo 36 alloy. For the mathematical analysis of the measurements, the number of experiments to be performed by using Minitab program and Taguchi method was reduced to 32. The measurement results were modelled by Response Surface Design method and the factors affecting the surface roughness were determined in order of importance. A high-performance feed-forward artificial neural network has been developed using experimental data and an interactive interface has been prepared based on the developed model. Thus, the user can easily observe the cutting forces and surface roughness values for different cutting parameters with high accuracy.

In industrialization, to be able to make cheap and fast production, assembly lines are one of the most basic elements in serial production systems. It is important to balance the assembly line to continue production smoothly. By assembly line balancing is created, each work step is grouped, stations are created and each station time is brought close to the station cycle times. In this study, a refrigerator top panel pressing line is analysed. The study’s aim is balancing the line for increase production rate. Firstly, the line is observed and some studies are planned. A time study is done to analyse the current situation of the line. Time study data are calculated by using Excel. Ranked Positional Weight Method is used as an intuitive method for single model U type assembly line balancing problem and mathematical modelling method is applied. The methods are used to balance the line using time study data. The solution of mathematical modelling is obtained by using Lingo. Results are compared and they are observed that results have almost the same. In conclusion, an assembly line balancing problem is mentioned in this study. Various programs related to the applied methods were used, and the data obtained as a result of current and final calculations were compared. First and last calculations and results are verified with each other. It was seen that the data obtained as a result of the study provided improvement.

In addition to conventional retrofitting of constructions, new technologies are rapidly being developed to withstand the external effects while sustaining an acceptable level of damage. Reinforced concrete structures strengthened with fiber reinforced polymer composite materials are becoming more and more widespread in structural applications due to their better mechanical properties, resistance to environmental influences, ease of application and light weight, as well as conventional methods of strengthening. In this study, strengthening technique as a methodology for externally bonded with carbon fiber reinforced polymer (CFRP) sheets to increase the flexural resistance of reinforced concrete beams has been investigated. For this purpose, eight reinforced concrete beams were produced considering different types of CFRP configuration and tested under four-point bending loading. The dimensions of the beams are 150×250×2600 mm and concrete cover of the first and second group of test beam are 20 mm and 40 mm, respectively. Finally, load-deflection behavior with the failure mechanism of the tested beams have been discussed and the effect of different schemes of strengthening on the flexural behavior has been evaluated.

In structural analysis, there are serious interactions between soil-foundation and structure. The fixed base analysis method ignores this interaction but many analysis methods have been developed that take into account the soil-structure interaction (SSI). This paper revealed the effects of SSI analysis methods on tall buildings analysis results on soft soil sites. 6 different structural models with 20 story buildings and two different coefficients of subgrade reactions were analyzed with three different analysis methods which are fixed base method, Winkler method and pseudo-coupled method. As a result of all the analysis, 6 different structural models compared and discussed in terms of structural period, displacements, lateral loads, column, shear wall and foundation reactions and structural economy. It has been observed that the structure may remain on the unsafe side in the analysis made with the fixed base analysis method.

Increasing the speed of transportation has been a subject that human beings have been working on for many years. Because of insufficient traffic corridors, the interest of more passenger in limited time and the advancement of railway technology, the high-speed ground transportation systems have developed. Nowadays, these time-saving transportation systems are becoming important increasingly and systems that will ensure these are implemented and new ones are being researched. High speed ground transportation systems can be divided into three categories: Conventional high-speed railway, Maglev and Hyperloop transportation system. Within the scope of this study, it is aimed to investigate the advantages and disadvantages aspects of high speed transportation systems by comparing in terms of speed, capacity, energy consumption, cost and environmental effects. Conventional high-speed railways can provide high capacity, comfort and safety and reliability thanks to enormous operational experience as regards other systems. The Maglev technology can offer more remarkable travel times, energy efficient and better operational performance. However, high investment cost and incompatibility with other modes are seen the disadvantage features of this technology. The Hyperloop technology is a considerable innovative transportation system which is popularized with publishing design document by Elon Musk in 2013. Projected high-speed and appealing travel times can be evaluated as the advantages of the Hyperloop transportation system. However, there are safety, reliability, comfort and engineering design challenges to overcome in this technology. Taking everything into consideration, the Hyperloop transportation system has potential to be an alternative mode to other systems.