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In this study, a metaheuristic Particle Swarm Optimization based optimization tool has been designed to be used in the optimization of Hybrid Renewable Energy Systems, which eliminates the negative aspects of the most frequently used HOMER software in this field. In the comparison made in terms of processing speed, it was seen that the designed system reached the result faster by obtaining the result in 17 seconds, which the HOMER software obtained in 936 seconds in optimizing the same system. In the economic comparison, as a result of the optimization made by two different tools; There is a difference of 1.737% in Energy cost, 0.85% in Total Net Present Cost and 1.895% in Initial Capital, and there is no significant difference between the results. In the comparison of the electrical results, there is a difference of 0.031% for the fed loads and 1.071% for the unmet loads, and the reliability of the results in electrical terms has been demonstrated. The capacity shortage parameter was used for the first time in the optimization of renewable energy sources with the metaheuristic algorithm. Energy Cost is used as the objective function. In short, a unique and reliable optimization tool has been designed as an alternative to the HOMER program that can achieve much faster results and eliminates the sensitivity, cumbersomeness and difficult search space generation processes in the HOMER program. This tool will also facilitate the generation of a large amount of data by obtaining the necessary optimization outputs very quickly to train surrogate models, machine learning or deep learning based optimization systems. [ABSTRACT FROM AUTHOR]

Wind energy is a very popular renewable energy resource and is used as an energy source global because of its benefits of being environmentally friendly, renewable and having great reserves. The probability density distribution of wind speed can be used to estimate wind power density. In this study, Weibull and Rayleigh density distributions were employed to analytically eliminate the presumption that the total wind power is described by a single random variant and to calculate the wind power probability density distribution. In the modeling of complex high-dimensional stochastic wind power, although it can be solved with various mathematical approaches, since there are generally large-scale power systems containing many generators, buses, planning periods and non-linear stochastic variables, it is quite leisurely in searching for the optimum point and most of the time the solutions are far from reality. Consequently, heuristic methods have now substituted classical mathematical methods in obtaining wind parameters. Therefore, the advantage of heuristic methods compared to classical methods is that they can produce efficient solutions in a shorter time and with greater precision. Therefore, in this study, the main metaheuristic algorithms Symbiosis Organisms Search (SOS) and Artificial Bee Colony (ABC) algorithms and the classical statistical methods Energy Pattern Factor and Maximum Likelihood Method were employed to investigate the accuracy of wind power parameter calculations. [ABSTRACT FROM AUTHOR]

Poliester liflerinin hidrofobik yapısı, yüksek kristalinitesi, lifleri oluşturan makromoleküller arasındaki yüksek çekim kuvveti gibi özellikleri boyanmasında önemli kısıtlar oluşturur. Ayrıca, poliesterin boyanmasında kullanılan yöntem ve kimyasallar çevre için zararlıdır. Bu çalışmada, bu sınırlamaları ortadan kaldırmak ve daha çevre dostu boyama prosesi geliştirmek amacıyla, poliesterin doğal boya ile boyanabilirliği ve yanıt yüzey metodoloji ile işlem parametrelerinin optimizasyonu araştırılmıştır. Bu kapsamda öncelikle pH, sıcaklık ve süreden oluşan üç faktör için Box-Behnken deneysel tasarımından baz alınan üç seviye belirlenerek bunlara yönelik deneysel çalışmalar gerçekleştirilmiştir. Gerçekleştirilen deney sonuçlarına bağlı olarak L*, a*, b*, C* gibi farklı çıktıları tahmin etmek için kullanılabilecek bir meta model oluşturmak amacıyla yapılan incelemelerde, literatürde de genel olarak kullanılmakta olan ikinci dereceden bir modelin ilgili sonuçlarını tahmin etmede başarılı olduğu (𝑅2 ≥ 0,9) ve bazı tasarımlarda ilgili 𝑅2 değerlerinin 0,99 seviyelerine yaklaşmakta olduğu gözlenmiştir. Benzer şekilde bazı çıktılar için 0,1720 ortalama mutlak hatayla deney sonuçlarını tahmin edebildiği görülmektedir. Buna ek olarak, oluşturulan model denklemlerinden teorik optimal boyama koşulları tespit edilmiştir. Sonuçlar poliesterin boyanmasında pH-sıcaklık ve pH-süre ikililerinin, sıcaklık ve süreye göre çok daha etkili olduğunu ve ayrıca alınan yüksek yıkama haslıkları bu boyama prosesinin açık-orta tonlarda sürdürülebilir boyamalar için kullanılabileceğini göstermiştir. Ayrıca bu çalışmanın maliyet ve zaman tasarrufu sağlama potansiyeli de vardır.

The additive manufacturing method offers a number of advantages such as rapid prototyping, design flexibility and unique part production. However, compared to traditional production methods, the production volume is limited. Therefore, to meet large-volume production demands, additive manufacturing is not as effective as traditional methods. In order to overcome this disadvantage, scientists are conducting research on the assembly of parts produced by additive manufacturing method. This study focuses on investigating the MIG (Metal Inert Gas) weldability of AlSi10Mg SLM (Selective Laser Melting) plate to AlSi10Mg SLM plate and subsequently optimizing the welding parameters for welding zone hardness and tensile strength. The most suitable parameters obtained in the hardness optimization of the weld zone were determined as 20.6 V, 120 A, 5356 (AlMg5). The most suitable parameters for tensile strength optimization were determined as 20.6 V, 110 A and 4047 (AlSi12). In addition to all these, 4047 filler material is thought to be the most suitable weld filler material for this study, as it provides the best tensile strength performance, offers acceptable weld zone hardness and is relatively easily accessible in the market. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have the potential to replace fossil fuel vehicles with advantages such as energy-saving capabilities and lack of exhaust pollution. However, pure electric vehicles still face limitations such as poor energy consumption, long charging times, and short battery range. Therefore, the use of hybrid energy storage systems (HESS) in EVs is becoming widespread. In this study, a new controller design was realized using the lungs performance-based optimization (LPO) algorithm and the energy consumption demands of EV HESS were optimized thanks to the designed system. The performance results of the proposed system were compared with other EV HESS management systems in the literature, and it was concluded in this study that the proposed LPO-based system is much superior to previous methods, typically reducing energy consumption by %21.86. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Ürünleri Dergisi is the property of Ege Journal of Fisheries & Aquatic Sciences (EgeJFAS) / Su Urunleri Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The scale, which is separated during the mechanical processing of fish, can be used in in many other different ways besides the production of collagen products. To obtain high-purity natural collagen, it is necessary to remove non-collagenous proteins and perform demineralization of fish scales. Therefore, the aim of this study is to achieve collagen isolation from common carp (Carasobarbus luteus) scales for the production of collagen products with higher efficiency and quality. The demineralization of the scales was optimized using response surface methodology. Experimentally, approximately 89.92±1.10% of the mineral was removed, which closely matched the value predicted by the model. The protein content of the fish scales was increased from 23.12% to 86.16% after the applied procedures. At the end of all the processes, 20.54% of the protein and 3.56% of hydroxyproline (Hyp) were lost. However, the Hyp concentration in the fish scale samples increased from 23.85 to 56.13 mg/g scale, and the Hyp/pro ratio increased from 4.49% to 6.51%. The effective removal of mineral matter, the increase in the amount of Hyp in fish scales, and the increase in the Hyp/pro ratio demonstrate that the applied procedures successfully separate non-collagenous components and achieve collagen isolation. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mugla Journal of Science & Technology is the property of Mugla Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Academic Social Science Studies is the property of Journal of Academic Social Science Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Properties of polyester fibers such as their hydrophobic structure, high crystallinity, and high attraction force between the macromolecules that make up the fibers create important restrictions on dyeing. In addition, the methods and chemicals used in dyeing polyester are harmful to the environment. In this study, in order to eliminate these limitations and develop a more environmentally friendly dyeing process, the dyeability of polyester with natural dye and the optimization of process parameters with response surface methodology were investigated. In this context, first of all, three levels based on the Box-Behnken experimental design were determined for the three factors of pH, temperature and time, and experimental studies were carried out on them. In the examinations carried out to create a meta model that could be used to predict different outcomes such as L*, a*, b*, C* depending on the experimental results, it was concluded that a second-order (quadratic) model generally used in the literature was successful in predicting the corresponding results (R² ≥ 0.9) and it was observed that corresponding R² approaches 0.99 in some of the designs. Similarly, it was noted that the we could predict the results of the experiments with a mean absolute error of 0.1720. In addition, theoretical optimal dyeing conditions were determined from the created model equations. The results showed that the pH-temperature and pH-time pairs were much more effective than the temperature and time in dyeing polyester, and also the high washing fastnesses obtained showed that this dyeing process could be used for sustainable dyeing in light-medium shades. Moreover, this study has the potential to save costs and time, too. [ABSTRACT FROM AUTHOR]

The metal sheath and armor on the insulating layer of a high voltage cable not only limit the electric field but also protect the cable's insulator against mechanical effects. However, when the load current flows through the cable, currents and voltages occur on the armor and metal sheath, which increase the cable temperature and cause dangerous voltages. These cause insulation failures. In the literature, different grounding methods are suggested to prevent insulation failures. However, due to the increase in the effect of harmonic currents in recent years, it is seen that these grounding methods are insufficient to prevent insulation faults. In this study, a new grounding method based on multi-purpose optimization and artificial intelligence is proposed to prevent insulation failures caused by high harmonic current and voltage. In order to make an optimum grounding with this method, it is necessary to know the voltage, current and current harmonic distortion on the metal sheath and armor. For the determination of these parameter values, estimation methods consisting of hybrid artificial neural networks and regression methods were used. Hybrid artificial bee colony-artificial neural network (H-NE) and gaussian process regression (GPR) methods were selected from these groups according to their minimum training errors and used as objective functions in optimization algorithms. Since there are many objectives in the optimization of the proposed grounding method, the multi-objective optimization method has been used. In multi-objective optimization, optimum values for voltage, current and current harmonics on metal parts are obtained when H-YAK is used as the estimation method. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada ilk olarak, betonarme sürekli kirişlerin detaylı tasarımlarının minimum maliyetle yapılabileceği bir süreç tasarlanmıştır. Ardından bu problem üzerinde FDB-TLABC, TLABC, TLBO ve ABC algoritmalarının performansları değerlendirilmiştir. Bu amaçlarla öncelikle Türk betonarme standardı ve deprem yönetmeliği dikkate alınarak optimizasyon problemi oluşturulmuştur. Bir, iki ve üç açıklıklı kiriş örneklerinden oluşan bir problem takımı hazırlanmıştır. Bu problem takımı üzerinde yapılan testlerden algoritmaların optimum sonuca ulaşma performansları ile belirlenen makul çözümlere ulaşma süreleri ve başarıları belirlenmiştir. Optimum sonuca ulaşmada, TLABC ve FDB-TLABC algoritmalarının en başarılı algoritmalar olduğu görülmüştür. Kararlılık analizinden, TLABC algoritmasının en yüksek kararlılığa ve hıza sahip olduğu görülmüştür.

Günümüzde endüstriyel sistemlerde nesnelerin kavranması, taşınması ve sabitlenmesi için kullanılan robot tutucular önemli araçlar olarak öne çıkmaktadır. Özellikle robotik sistemlerde, bir nesneyi en az manevrayla zarar vermeden tutabilme yeteneği büyük önem taşımaktadır. Bundan dolayı, son yıllarda robot tutucularının tasarım optimizasyonu ilgi çeken bir araştırma konusu haline gelmiştir. Bu çalışmada bu tasarım problemi için aritmetik optimizasyon algoritması (AOA) iyileştirilmiş ve çok stratejili aritmetik optimizasyon algoritması (ÇSAOA) adında yeni bir algoritma önerilmiştir. Bu algoritmada hem orijinal AOA’nın güncelleme mekanizmasını modifiye edilmiş, hem de farklı bir güncelleme mekanizması eklenilerek kendinden uyarlanabilen bir algoritma haline getirilmiştir. Bu yaklaşım, en iyi güncelleme stratejisine odaklanarak problemi daha verimli bir şekilde çözmeye olanak sağlamıştır. ÇSAOA, robot tutucu problemine uygulandığında, orijinal algoritmaya göre hem performans hem de hesaplama süresi açısından daha iyi sonuçlar ürettiği gözlemlenmiştir. Ayrıca, bu yeni algoritma literatürdeki diğer benzer algoritmalarla karşılaştırılmış ve önerilen ÇSAOA’nın daha performanslı algoritma olduğu görülmüştür.

Günümüzde alüminyum alaşımları hafif olması, yüksek dayanım sunması ve ekonomik olmaları gibi sebeplerle havacılık, otomotiv ve savunma sanayiinde yoğun olarak kullanılmaktadır. Bu çalışmada Al2024-T3 malzemesinin işlenmesinde elektro erozyon yöntemi kullanılarak, talaş kaldırma miktarı (TKM), takım aşınma miktarı (TAM) ve ortalama yüzey pürüzlülüğü (Ra) olarak sıralanabilecek performans yanıtları üzerinden sonuçlar elde edilmiştir. Yapılan deneylerde boşalım akımı (Ip), vurum süresi (Ton) ve vurum aralığı (Toff) parametrelerinin performans yanıtları üzerindeki etkileri incelenmiştir. Yapılan varyans analizi (ANOVA) sonucunda deney sonuçları üzerinde etkin parametrelerin sırasıyla Ton, Ip ve Toff olduğu tespit edilmiştir. Çalışmanın devamında performans yanıtlarını eniyileyecek parametre değerlerinin tespiti amacıyla bir optimizasyon çalışmasına da yer verilmiştir.

Traffic control strategies aim to increase traffic efficiency by providing effective solutions to issues such as reducing traffic congestion, reducing the average travel time and preventing accidents. The most appropriate strategies can be determined by using factors such as analyzing the traffic situation, traffic modeling, traffic signaling systems, traffic markings and technological solutions Decoupled together. It is seen that multi-criteria decision-making approaches provide great usefulness in determining these strategies. Multi-criteria decisionmaking is a systematic approach used to make decisions based on multiple criteria and goals instead of a single factor. Multi-criteria decision-making allows decision-makers to sort alternatives using an appropriate scale, take into account all relevant factors and make the best possible choice. Despite this importance, it is observed that there are not enough studies in the literature on the effect of multi-criteria decision-making approaches on traffic control strategies. Considering the complex nature of the traffic phenomenon and the importance of traffic for human life, the need for academic studies to be conducted on this issue is quite high. In this study, the role of multi-criteria decision-making approaches in determining optimal traffic control strategies will be examined. Qualitative methods will be used in the study. Firstly, a literature review will be conducted on the subject, and based on previous studies, existing gaps will be determined. Then, optimal traffic control strategies and multi-criteria decision-making approaches used in traffic control strategies will be explained. After this theoretical basis, multi-criteria decision-making approaches will be evaluated, some sample models will be applied in determining optimal traffic control strategies with qualitative relational analysis. The purpose of the study is to develop decision support systems and provide tools to assist decision makers in implementing traffic control strategies. The thesis of the study is that multi-criteria decision-making approaches are highly functional in determining optimal traffic control strategies. [ABSTRACT FROM AUTHOR]

K-Means clustering is commonly used for data clustering, but it suffers from limitations such as being prone to local optima and slow convergence, particularly when handling large medical files. The literature recommends employing metaheuristic algorithms in clustering studies to address these issues. This study aims to accurately diagnose diseases in four medical datasets (Dermatology, Diabetes, Parkinson's, and Thyroid) and increase the rate of correct diagnosis of diseases. We utilized optimization algorithms to assign weights to input parameters determining diseases in these datasets, thereby improving clustering performance. Our proposed model incorporates the Crow Search Algorithm, Tree Seed Algorithm, and Harris Hawks Optimization algorithms in a hybrid structure with K-Means. We conducted statistical evaluations using performance metrics. The study demonstrated that the hybrid Harris Hawks Optimization algorithm achieved the highest accuracy rate (97.19%) among the tested algorithms on the Dermatology dataset. The hybrid Crow Search Algorithm obtained a 96.29% accuracy rate on the Thyroid dataset, while the hybrid Tree Seed Algorithm achieved a 95.32% accuracy rate on the Dermatology dataset. This study offers significant benefits, including reduced staff workload, lower test costs, improved accuracy rates, and faster test results for detecting various diseases in medical datasets. [ABSTRACT FROM AUTHOR]

Copyright of Karaelmas Science & Engineering Journal / Karaelmas Fen ve Mühendislik Dergisi is the property of Karaelmas Science & Engineering Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Selcuk University Journal of Science Faculty / Selçuk Üniversitesi fen Fakültesi fen Dergisi is the property of Selcuk University Journal of Science Faculty and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural wastes are abundant worldwide with increased production and consumption activities as a result of human population growth. Waste recycling processes, which are important to support sustainable production, remain popular due to the increasing amount of agricultural waste. In particular, there are various studies on the recovery of valuable components from waste. In this context, the recovery of cellulose and nanocellulose from waste, which has the potential to be used and applied in many sectors, especially in food, draws attention. Although black carrot juice waste, which is one of the important agricultural wastes, is frequently used in the production of natural colorants, it was used for the production of cellulose and nanocellulose in this study due to its high cellulose content. Response Surface Method-Central Composite Design was used to improve the alkaline extraction conditions of cellulose for the optimum yield and whiteness index by using process parameters of NaOH concentration (2-12%), process temperature (25-110 °C), and time (60-240 min). The optimum process parameters were determined as the NaOH concentration (7.06%), process temperature (44.83°C), and time (114.21 min) for alkaline extraction of cellulose from black carrot juice waste where the yield of cellulose was 22.90±2.48%, and whiteness index was 60.32±0.07%. Nanocellulose was produced from cellulose obtained from black carrot juice waste by acidic hydrolysis using 25% H2SO4. Nanocellulose yield and whiteness index were found as 15.76±0.16% and 58.77±0.26% respectively. The average diameter (61±2.89 nm) and length (281±18.50 nm) of the nanocellulose were determined by Atomic Force Microscopy (AFM). As a result of the Fourier Transform Infrared (FTIR) spectroscopy, it was determined that non-cellulosic components were removed. [ABSTRACT FROM AUTHOR]

Öz Topology optimization has become a valuable tool in the aerospace industry, enabling engineers to develop aircraft components with improved performance characteristics while reducing their weight. The technique has also allowed for the design of complex structures that were previously unattainable using traditional manufacturing methods. In this study, a comprehensive topology optimization of the steering pump housing for an aircraft's nose landing gear was performed using the nTopology software. The primary objective of this optimization was to reduce the weight of the steering pump housing while preserving its mechanical properties, which are essential for safe and reliable operation of the nose landing gear system. The study demonstrates the potential for topology optimization to be an effective tool for reducing the weight of aircraft components while preserving their mechanical properties. This approach can be applied to other aircraft components with similar design challenges, and could potentially lead to significant weight savings in the overall design of the aircraft. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Firat University Journal of Experimental & Computational Engineering (FUJECE) is the property of Firat University Journal of Experimental & Computational Engineering (FUJECE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In sheet metal forming processes, tearing problems might be occasionally encountered due to many reasons such as incorrect forming parameters. The trial and error methods that are used to solve such problems, on many occasions, are time-consuming and inefficient in terms of finding the correct forming parameters or die design for the forming process. The finite element analysis method, on the other hand, can be used as a tool that is both time and cost-saving. However, in order to effectively exploit the use of finite element analysis in sheet metal forming operations, the material that is used to be formed needs to be well characterized in terms of its hardening behaviour and failure criteria. In this study, a TRIP-aided DP steel (DH780) has been tensile tested in three different deformation conditions (uniaxial, plane stress and shear) and the parameters of its hardening model (Hollomon) and failure criteria (Modified Mohr-Coulomb) have been determined. According to the simulation results, obtained hardening parameters are able to describe the flow behaviour of the steel and the used failure criterion is able to predict the experimental failure correctly in each deformation condition.

Bu çalışma kapsamında, otomotiv sektöründe kullanılan amortisörün bağlantı ekipmanlarından biri olan klevis braketin üretiminde rol oynayan projeksiyon kaynak prosesinin iyileştirilmesi ve projeksiyon kaynak parametrelerinin klevis braketin mekanik performansını nasıl etkilediği araştırılmıştır. Bu kapsamda, 9 farklı proses kullanılarak numuneler üretilmiş ve bu numunelerin kopma testleri yapılmış ve elde edilen sonuçlara göre ANOVA analizi uygulanmıştır. Analiz sonucunda, en etkili parametrenin %80 oranında kaynak basıncı olduğu ve kaynak sıkma süresinin etkisinin ihmal edilebilecek düzeyde olduğu belirlenmiştir. Ayrıca, projeksiyon kaynağıyla yapılan 5 farklı noktanın en kritik 2 noktasının kesitlerinin makro ve mikro yapısı incelenmiştir. Kaynak süresinin artmasıyla birlikte ısıl girdinin arttığı ve bunun sonucunda mikro yapıdaki ısı tesirli alanların ve füzyon bölgesinin boyutlarının arttığı gözlemlenmiştir. Bununla birlikte, kaynak basıncının artması mikro yapıyı olumsuz yönde etkilemiştir. Ayrıca, kaynak kesitlerinin ortalama sertlik değerlerinin, bu mikro yapıdaki değişimden etkilendiği gözlenmiştir.

The performance of high-lumen light-emitting diode (LED) arrays is strongly affected by high temperatures. For better performance, the design of better thermal management techniques is required. In this work, an analytical thermal optimization algorithm for the passive heat sinks of high-lumen LED arrays is presented. With the aid of this algorithm, a broader range of heat sink geometry alternatives can be explored for the identification of the optimal heat sink design. This task is challenging using experimental or numerical techniques. The results demonstrate that the algorithm yields design with a reduction of more than 30% in base temperatures compared to previous heat sink design studies when minimum mass and maximum total efficiency constraints are applied. For devices with high powers, small chip spacing, and space limitations in the horizontal axis where base temperatures cannot be further reduced using these constraints, minimum temperature optimization can result in up to a 17% reduction in base temperatures. This reduction in base temperatures significantly improves the junction temperatures and the overall lighting quality of the LEDs. [ABSTRACT FROM AUTHOR]

Battery is one of the largest contributors to the weight of electric vehicles, and its location directly affects the performance of the suspension system. The aim of this article is to determine the optimal battery locations for ride comfort of in-wheel-motor electric automobiles using a nonlinear vehicle suspension model. In the analyses, a seven-degree-of-freedom half-vehicle suspension model was used, in which cubic nonlinearities of all springs and dampers are taken into account in addition to their linear characteristics. In addition to spring and damper nonlinearities, all trigonometric nonlinearities are also considered in the model. Totally 144 different driving scenarios were generated with 48 different sinusoidal road profiles and 3 different travel speeds, and for each scenario by testing 36 battery locations along the vehicle's longitudinal axis, the optimal one was found. The optimization criterion is the minimization of the root-mean-square of the vertical acceleration of the driver and seat. As a result of the 5184 analyses carried out, it has been seen that the optimal battery location is the middle of the vehicle for road profiles with wavelengths between 0.2 and 5 m, whereas the rear of the vehicle for road profiles with wavelengths between 10 and 30 m. [ABSTRACT FROM AUTHOR]

In this study, photocatalytic degradation of 2,4 Dichlorophenoxyacetic acid (2,4D), one of the the most used pesticide, was investigated by TiO2 photocatalyst produced by sol-gel method. Three different parameters (Titanium isopropoxide (TIP) amount, HNO3 concentration and aging time) were investigated and modelled by applying Box Behnken Experimental Design method for optimum TiO2 synthesis. Photocatalyst production process was optimized by examining the 2,4D photocatalytic degradation rate of TiO2 photocatalysts produced under different process conditions. TiO2 samples, which were synthesized with the optimum conditions, were characterized by XRD (X-ray Diffraction), SEM (Scanning Electron Microscope), zeta potential, particle size analysis, and also compared with commercial Degussa P25 TiO2 photocatalyst. 2,4D photocatalytic degradation rate was determined as 0.0084 min-1 for the optimum condition 1 (TIP amount: 24.08 mL, HNO3 concentration: 3.53 M, aging time: 2.29 hours) and 0.0085 min-1 for the optimum condition 2 (TIP amount:10.33 mL, HNO3 concentration: 0 M and aging time: 19.51 hours). The amount of used acid was reduced to zero or the aging time was reduced to the lowest value (2.29 h) by optimizing the TiO2 production parameters via experimental design methodology, hence, a very high photocatalytic efficiency was obtained. [ABSTRACT FROM AUTHOR]

Although starch-derived glucose syrups have a wide share in industrial applications, health-related discussions mainly highlight the use of sucrose by consumers. Sucrose can be hydrolyzed by acidification or enzymatic methods to form glucose and fructose monomers, called invert sugars. Among these methods, enzymatic hydrolysis process is a preferred method in the industry because it occurs at lower temperatures and produces less toxic waste compared to traditional chemical processes. However, the enzymes used in the hydrolysis process are generally molecules that are difficult to reuse and have low stability, and their high production costs make it difficult to apply them on an industrial scale. The aim of this study was to determine in detail the effect of the independent variables that are important in the hydrolysis of sucrose by the invertase enzyme on sucrose conversion rate, hydrolysis efficiency, and total reducing sugar concentration using the Central Composite Design (CCD) experimental design method. A model equation including enzyme activity was established between the independent variables and response variables examined in the experiments performed with MKD. Within the examined ranges of the independent variables, as a result of the optimization process for the conditions where both the reducing sugar concentration and the conversion of the mathematical model expression are maximum; sucrose concentration was determined as 190.16 g/L, enzyme activity as 55.36 U/mL, temperature as 33.46 oC, reaction time as 131.10 min, and mixing speed as 120.86 rpm. As a result, efficient processing conditions for the enzymatic hydrolysis of sucrose were determined. [ABSTRACT FROM AUTHOR]

In this study, firstly, a process by which detailed designs of RC continuous beams can be made with minimum cost was designed. Then, the performances of the FDB-TLABC, TLABC, TLBO, and ABC algorithms on this problem were evaluated. For these purposes, first, the optimization problem was created by taking into account the Turkish reinforced concrete standard and earthquake regulations. A problem set consisting of one, two, and three-span beam samples was prepared. From the tests carried out on this problem set, the performance of the algorithms to reach the optimal result and the time to reach feasible solutions and their success were determined. It was seen that the TLABC and FDB-TLABC algorithms are the most successful in reaching the optimum result. From the stability analysis, it was seen that the TLABC algorithm has the highest stability and speed. [ABSTRACT FROM AUTHOR]

Health industry provides services that directly intervene in human life and quality of life, however, it is also affected by economic conditions as much as other industries, regardless of its importance for society. Healthcare service providers and managers must have a management approach that enables the development of economic formulas that will not negatively affect the quality of service to cope with increasing costs. The development of scheduling approaches in healthcare units plays a critical role in service quality components such as reducing costs, using resources optimally, improving patient flow, and reducing the required time for treatment processes. In this study, a model-oriented decision support system is developed to help dialysis center managers adopt the necessary approach during patient-session scheduling. The two most important resources for dialysis treatment businesses are dialysis machines and healthcare personnel. The optimal use of one resource can lead to failure in achieving the desired efficiency in the other resource. Scheduling activities in dialysis centers are traditionally performed based on staff experience and intuition. However, the automation capabilities of a Decision Support System (DSS) provide time and effort savings by eliminating manual methods. Computer-based algorithms and optimization techniques are used to effectively plan and allocate resources, resulting in accelerated processes and improved efficiency.". [ABSTRACT FROM AUTHOR]

The risk-free interest rate is one of the most important parameters used by finance theory. The reason for the difference in risk-free rate preference may be the personal decisions of practitioners or the difficulties they encounter in accessing data. However, the consequences that may arise from different decisions taken in choosing this ratio are of importance that should not be ignored. In this study, the possible effects of the change in risk-free interest rate selection on optimal asset allocation were examined specifically in Borsa Istanbul. It was examined the 10 sub-indices selected within the scope of the research (XBANK, XELKT, XGMYO, XGIDA, XKMYA, XMANA, XSGRT, XUTEK) through optimization for the period 31.12.2007-31.12.2022 with monthly frequency. When the optimization results performed with 5 different risk-free interest rates selected as reference were examined, it was determined that the variation in the risk-free rate affected the optimal asset distribution and therefore return and risk of the portfolio. This result is important for both individual and corporate actors who use the risk-free rate in financial decisions and transactions to see the possible effects of the difference in the relevant rate. [ABSTRACT FROM AUTHOR]

Copyright of Harran Journal of Agricultural & Food Science is the property of Harran University, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pamukkale University Journal of Business Research / Pamukkale Üniversitesi İşletme Araştırmaları Dergisi is the property of Pamukkale University Journal of Business Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The nursing workforce problem is essentially a scheduling problem. Scheduling problems involve the efficient planning and sequencing of specific resources, aiming to find the best time schedule that meets all constraints. Genetic Algorithm can be utilized to solve scheduling problems effectively. In this study, taking into account the success of the Genetic Algorithm in scheduling problems, a software has been developed in the Python environment to ensure the optimal assignment of nurses in clinics. The Genetic Algorithm-based software operates on a population basis, seeking to find the best schedule that satisfies various tasks and constraints. During the study, the planning of nursing staff considered the possibility of different clinics within the hospital, each dealing with patients requiring different care durations. It was assumed that a nurse works according to legal restrictions. Furthermore, a 4-week period was taken into consideration during the scheduling process, and the program was executed for a total of 28 days (a total working time of 160 hours). As a result, a software solution was presented that can successfully achieve an optimal nurse assignment, enabling the complete fulfillment of patients' care requirements in a given clinic. [ABSTRACT FROM AUTHOR]

The machinability of a material depends not only on its mechanical properties and microstructure, but also on the selection and control of process variables. By changing the cutting fluid, speed and depth in GGG-70 material, channels have been opened on the material surface by milling process with a width of 10 mm and a length of 50 mm. The machining process was carried out using a minimum amount of lubricant (MQL). As a result of experiments with different processing parameters, the surface roughness and surface hardness of the material were measured. Compared to the uncut surface hardness, an average hardness reduction of 2%-10% occurred as a result of milling. The level of cutting parameters did not cause a statistically significant change in the surface hardness value. The mathematical model between different cutting parameters and surface roughness was obtained decisively by regression analysis. The optimum parameters of the cutting fluid, its speed and depth were found by the Bees Algorithm, which is a meta-heuristic methods optimization method. According to the Bees Algorithm, the optimum milling conditions are vegetable oil, 180 m/min cutting speed and 0.5 mm cutting depth. Especially, the optimum performance of vegetable oil compared to boron oil is important from the point of view of sustainable environment. [ABSTRACT FROM AUTHOR]

In this study, an optimization model has been developed to plan the restoration works envisaged to be done in historical buildings. There are very few studies in the literature on modeling the restoration works of historical monuments and cultural heritages, and most of these studies are based on multi-criteria decision-making models that aim to prioritize the works to be done. Restoration of historical monuments is an expensive and long process. Considering the cultural, social and economic importance of the buildings under the assumption that the works under restoration will be closed to visitors, the importance of optimizing the restoration works is understood. However, no study has been found in the operations research literature that deals with this problem in the scope mentioned. Where the minimum set of actions required to correct defects in a building is termed a 'work', it can be assumed that there may be more than one 'work' due to different defects in a building. Restoration works need to be assigned to work packages and scheduled according to the limited budget allocated for the restoration of the works. Since the budget is limited, the entire budget allocated for a certain period is reserved for only one work package. That is, work packages cannot be executed in parallel, a new work package cannot be started before a work package is completed. It is conceivable that similar types of work could be done by the same teams. There are economic advantages for similar works to be done by the same teams for different historical buildings located at close distances to each other. Under the assumption that the building will remain closed to use/visit before all the restoration works on a work are completed, it can be aimed to complete the restoration works of the buildings as early as possible. In this context, with the developed mathematical model, it is aimed to assign the works to the work packages by taking into account their similarity and geographical proximity, thus making optimal assignment and scheduling under limited budget conditions. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)