Authors:Mustafa DEMİRTAŞ Abstract: In this study, a novel hybrid algorithm consisting of the least mean square and backpropagation neural network is proposed to auto-adjust adaptive proportional integral derivative (PID) controller gains for improving the transient response of linear systems. The hybrid approach comprises the scheme of the two algorithms running in parallel and updates PID gains simultaneously. All algorithms are implemented on the same linear system and present a general framework for different scenarios such as initial PID gains, learning rates, and target functions. The results show that the presented hybrid algorithm has better accuracy, precision, F1-score, adaptability, and robustness than origin algorithms, and significantly improves the controllability in most of the system scenarios. It also exhibits better performance in periodic incremental and decremental targets compared to origin algorithms. Different hybridization levels are also simulated and are highlighted as significant features of their performance. This work can be expanded to the combination of other well-known algorithms, paving the way to significant improvements in control system applications. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Nihat PAMUK Abstract: The efficient transmission of electrical energy depends on amplifying voltage values with power transformers. To obtain higher efficiency from transformers, the core and winding type of transformer, the geometric structure of the core, and the shaping techniques in the windings are changed. This requires modeling transformer windings with equivalent circuits and calculating the inductance and electrical parameters appropriately. In this study, two-dimensional (2D) finite element solutions with energy perturbation and flux-coupling methods are used. The correctness of the inductance values of transformer windings was established, and the design was performed, by considering the inductance and electrical parameter values, which are comparable to the energy perturbation and flux connection. However, when two-dimensional calculated fields are used, the flux coupling method requires less computation and gives numerically more accurate results than the energy perturbation method. So, it is concluded that the flux-coupling approach should be chosen as the preferred method for calculating the inductance and electrical parameters of transformer windings. The numerical properties and equivalence of energy perturbation and flux-connection methods, the “apparent” inductance value of the primary and secondary field windings of power transformer operating under transient conditions, using the temperature-time parameter method, are calculated and its accuracy is demonstrated. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Ergun ATEŞ Abstract: In this study, unsaturated polyester resin for general use and woven E-glass fiber were used as the components required for structure formation and as the reinforcement material. In the production of target composite plates prepared as square and circular sections, the thickness of the composite plates was variable, together with the number of fiber layers. The shots were fired on target composite plates from a distance of 10 m at the range, using two different weapons that fired 22-caliber and 9-mm rounds, respectively. As a result of the shots, it was determined that if the number of woven fiber layers was 9 and the plate thickness was greater than 12 mm, the target composite was successful against 22 caliber and 9 mm bullets. The level of protection for composite plates has been determined to be IIA according to NIJ Standard-0101.06. The target is of vital importance in shooting with a gun, and in this study, the characteristics of the target composite plate that prevent the bullet from passing gave results according to the determined production operating parameters. For increased shell calibers, it is necessary to carefully plan the target composite production parameters and necessarily conduct field shooting experiments. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Hatice Şule ÇOBAN TETİK; Cemile Betül EMRULLAHOĞLU ABİ Abstract: High-quality alumina raw materials allow corundum-based brick and monolithics to perform to the full potential of alumina as a refractory material. Dense packing of the matrix to a submicron range and reduction of water demand of castables can be facilitated by a new family of multimodal reactive alumina. Dispersing aluminas ensure uniform mixing of dispersion and setting adjustment additives. In this study, fine reactive alumina powder production was investigated using Bayer gibbsite as a starting material. Experimental studies consist of two steps; in the first step, the soda content was reduced by means of boric acid and distilled water and then the powders obtained optimum conditions were ground in an attritor ball mill using distilled water for 8 hours. In the second step, physical characteristics such as rheological behaviours, bulk density, open porosity and thermal shock resistance, bending and compressive strength and fracture toughness in accordance with ASTM E399 standard were determined. Finally, KIC values of the refractory samples which was prepared with the reactive alumina produced from Seydişehir gibbsite were higher than that of the refractory mixture containing commercial reactive alumina obtained from a refractory company. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Çağatay SELVİ Abstract: The effects of different blade coating materials on force demands were examined in the present study. The force demands when cutting grape branches with St-52 steel, polytetrafluoroethylene (PTFE)-coated and Soft Teflon (STP)-coated lopper blades were measured. A universal testing machine was used as the simulated cutting task together with a force cell in the laboratory. Grape branches were the testing material. The differences between the force demands of blades were significant (P PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Zafer ÜNAL Abstract: Fibonacci and Lucas numbers have been the most popular integer sequences since they were defined. These integer sequences have many uses, from nature to computer science, from art to financial analysis. Many researchers have worked on this subject. Sedenions form a 16-dimensional algebra on the field of real numbers. Various systems can be constructed by using the terms of special integer sequences instead of terms in sedenions. In this study, we define dual Fibonacci (DFS) and dual Lucas sedenions (DLS) with the help of Fibonacci and Lucas termed sedenions. Then we calculate some special identities for DFS and DLS such as Vajda's, Catalan's, d'Ocagne's, Cassini's. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Ali Kaan YETİK; Tefide KIZILDENİZ, Zeynep ÜNAL Abstract: Sugar beet is an essential crop for the sugar industry that have a very crucial role in agro-industry of Türkiye and Konya ranks first in terms of total sugar beet production and harvested area. The predictions, that the world's human population will reach 9 billion by the end of the current century and that demand for food will increase, are forcing farmers for the decision to search for new areas for agriculture or choose the crops that will be most productive in already cultivated lands. The aim of this study was to apply the LINTUL-MULTICROP Model for investigating the adaptation of sugar beet for the current climatic conditions and for climate change scenarios to show the response of sugar beet to an increase level of carbon dioxide and temperature. Four different scenarios were compared to check the effects of the climate change on sugar beet farming in the semi-arid Konya Region as followings: i) scenario (a) is the current climate conditions; ii) scenario (b) is the average temperatures increased 2 °C, iii) scenario (c) is 200 ppm increasing atmospheric CO2; iv) scenario (d) new optimum sowing and harvest dates in sugar beet farming and increased temperatures and atmospheric CO2 amount were simulated together. The optimum sowing and harvesting dates of sugar beet were moved 13 days back for sowing, and 8 days forward for harvesting. The highest yield was estimated under conditions of 2 °C and 200 ppm increased atmosphere temperature and CO2 levels with new sowing and harvest dates. The yields under irrigated conditions varied between 74.4 t ha-1 and 111.2 t ha-1. The irrigation water requirements of sugar beet were ranged from 618.8 mm to 688.5 mm for different scenarios. In conclusion, the cultivation of sugar beet tends to alter in semi-arid Konya environment. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Doğan YILDIZ; Gülcan YILDIZ, Sercan DEMİRCİ Abstract: Increasing population density and climate changes resulting from global warming have significant effects on the amount and quality of agricultural production. Therefore, the world is facing severe problems, such as food shortages. Therefore, agriculture is a vital activity in countries' economic and social development programs. In the category of hard-shelled fruits, hazelnut is the most produced product in the world after almonds. Turkey meets approximately 70% of the world's demand for hazelnut, which is concentrated in countries such as Turkey, Italy, Spain, and the USA. For this reason, it is essential to determine the parameters affecting the yield in hazelnut production and to estimate the yield depending on these parameters. In this study, the parameters affecting the hazelnut production in the provinces of Sakarya, Düzce, Samsun, Giresun, Trabzon and the districts of these provinces where hazelnut production is made were examined, and the yield estimation to be obtained in the next step was made. In order to get the features required for the forecasting process, some pre-processing steps were applied to the raw data set, and the number of features was reduced by Principal Components Analysis (PCA). These pre-processed data were given as input to the XGBoost algorithm, Lean (Long Short-Term Memory, LSTM) model, Stacked LSTM model, (Convolutional Neural Network, CNN) model and CNN-LSTM hybrid model, and estimation was carried out. Finally, (Root Mean Square Error, RMSE) estimation error was obtained for each method and used for comparison. According to these results, the best performance with the lowest RMSE=1.32 value was obtained with the CNN-LSTM hybrid model. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Can ALTUĞER; Koray ULAMIŞ Abstract: Bilecik province is one of Türkiye's most important natural stone areas. In recent years, with the opening of new marble quarries around Bilecik, natural stone production has gradually increased in the region. There are many marble quarries in the study area located in the west of the Sakarya continent. The units belonging to this continent have undergone blueschist metamorphism. The Late Jurassic-Early Cretaceous units have undergone a transgression, which unconformably overlies the metamorphic units. Late Jurassic-Early Creates aged units with marble quarries consisting of the Bilecik Formation. There are white-pink, brown-grey, and beige-colored marbles in these units. Using the land use/land change (LULC) classification, the land change of the marble quarries in the region for every 5 years (2006, 2011, 2016, and 2021) has been shown by the remote sensing method. Landsat 5 TM and Landsat 8 OLI multispectral satellite images were classified by the Support Vector Machines (SVM) method, one of the machine learning methods. To prove the accuracy of LULC, an accuracy matrix, and Kappa index were created. The accuracy of the thematic maps was 95.75%, 92.00%, 93.60%, 95.20% and Kappa index values were 0.92, 0.86, 0.89, and 0.91, respectively. As a result of the increase in marble quarries, it brings an increase in the amount of solid waste. This situation can be will negatively affect the city in the future with the inadequacy of solid waste storage areas. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Burak ÖZDEMİR; Erkan BAHÇE, Mehmet Sami GÜLER Abstract: In this study, the effects of tool diameter on thrust force and vibration in drilling of GFRP (Glass Fiber Reinforced Polymer) composite material were investigated. For this purpose, GFRP composite plate was drilled with 5, 7.5 and 10 mm diameter tools while keeping other drilling parameters constant. During drilling, thrust force and vibration measurements were made. As a result of the statistical analysis of the obtained data, it was seen that the thrust force increased and the vibration decreased with the increase in the tool diameter. In addition, it was determined that the tool showed lower oscillation at higher diameters and made a stable drilling process. It is expected that the study will guide the selection of the tool diameter that will provide the appropriate hole quality in GFRP composite materials. In addition, it will provide support to researchers in detecting the negative effects of thrust force and vibration. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Ümit AKAR; Parisa DORAJ Abstract: Gestalt theory argues that first the integrity of a subject is understood and then its components are recognized. From this point of view, the visual principles and rules of such a perception can be defined. In this concept, the question arises whether it is possible to analyze historical gardens with Gestalt theory. It shows that since the emergence of Gestalt theory and years have passed, this theory has always been used and can be used in the field of landscape architecture. In order to prove this logic, first of all, the Iranian traditional four garden systems were examined through the Gestalt theory and the Taj Mahal example. In this direction, with the help of the concepts of Gestalt theory, some aspects of Iran's four gardens landscape architecture were reevaluated. As a method, the concepts of proximity, continuity, closure, similarity and good form, which are among the Gestalt principles, were discussed and examined in the Taj Mahal garden. In addition, the features of the Gestalt theory and how it affects the Iranian garden design as a perceptual factor have been revealed. In this respect, the relationship between shape and ground is designed and made from the same concept, from decorations to floor coverings. In conclusion, in this study, the relationship between Gestalt theory and landscape architecture has been examined, the structure of the Taj Mahal has been examined, and it has been discussed that Gestalt fiction is an effective concept in the design of such areas. PubDate: Sat, 01 Apr 2023 00:00:00 +030
Authors:Nesimi ULUDAĞ Abstract: Coumarins, which constitute a large class of natural compounds, are organic compounds that have attracted interest since the 19th century and have numerous practical applications. Coumarin compounds are heterocyclic compounds found in industry and in the structure of many commercial drugs. In this study, zinc-triflate-catalyzed tandem reactions of methyl 2-(phenylethyl) benzoate with but-3-en-2-one were applied for the synthesis of isocoumarins by a different method. The reaction was carried out under oxygen-free conditions using a convenient and environmentally benign reaction method in high yields and synthesized the targeted isoquamarine derivatives in a single step with the help of a novel catalyst. In addition, the effect of electron-withdrawing-electron-donating side groups on the formation and percentage yield of the reaction was investigated in this study. In summary, in this study, cascada reaction with palladium (II)-catalyzed highly regioselective but-3-en-2-one was developed. PubDate: Sat, 01 Apr 2023 00:00:00 +030
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