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AI-powered hybrid metaheuristic optimization for predicting surface roughness and kerf width in CO2 laser cutting of 3D-printed PLA-CF composites
No full textThis study explores the impact of CO2 laser cutting parameters on surface roughness and kerf width of 3D-printed Carbon Fiber reinforced Polylactic Acid (PLA-CF) composites while developing phenomenological models using hybrid artificial intelligence techniques. PLA-CF composites possess certain mechanical properties and surface quality. The surface roughness and kerf width values were measured under different laser cutting conditions (such as plate thickness, power, and cutting speed) and were predicted using multiple linear regression, particle swarm optimization-based adaptive neuro fuzzy inference system, and ant colony optimization-based adaptive neuro fuzzy inference system models. Experimental results showed that kerf width and surface roughness are influenced significantly by laser cutting parameters, showing the importance of accurately selecting the parameters. The most dominant factor entered the model as cutting speed: as cutting speed was increased, kerf width decreased, but higher levels of power resulted in kerf width. Thickness provided a non-linear input: kerf width decreased from 2 to 2.5 mm, then increased to 4 mm. The least kerf width (0.809 mm) was obtained at 90 W power and 9 mm/s cutting speed, with 2.5 mm thickness. Surface roughness increased with cutting speed and power, with minimum surface roughness (1.878 mu m) at 2 mm thickness and 90 W power with 3 mm/s cutting speed. Among the hybrid artificial intelligence models, the particle swarm optimization-based adaptive neuro fuzzy inference system model gave the best accuracy, achieving the lowest mean squared error and highest correlation coefficient, whereas the ant colony optimization-based adaptive neuro fuzzy inference system model performed better than multiple linear regression but not better than particle swarm optimization. These results, therefore, validate the applicability of hybrid artificial intelligence models for predicting surface quality and kerf width during CO2 laser cutting.Scientific Research Projects Coordination Unit of Bandimath;rma Onyedi Eylul University [BAP-24-1003-003]The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Scientific Research Projects Coordination Unit of Band & imath;rma Onyedi Eylul University under Project Number: BAP-24-1003-003
Electrochemical synthesis of NiCo layered double hydroxides on nickel-coated graphite for water splitting: understanding the electrochemical experimental parameters
No full textThe electrochemical synthesis of nickel-cobalt (Ni-Co) layered double hydroxides (LDHs) on a nickel-coated graphite support for water splitting applications was investigated. Three different electrochemical approaches, namely, cyclic voltammetry (CV), chronoamperometry (CA), and chronopotentiometry (CP), were employed for evaluating the electrodeposition of Ni-Co LDHs. The graphite support was initially coated with a thin layer of Ni by applying 50 mA cm-2 constant current density for 120 s. Raman spectroscopy results confirmed the intercalation of nitrates, evidenced by the characteristic Raman bands at 1033 cm-1 (nu 1) and 1329 cm-1 (nu 3). These characteristic bands were indicative of nitrate intercalation, a key feature of LDHs, further supporting the classification of the synthesized material as NiCo LDHs on a nickel-coated graphite support. It was observed that the electrochemical routes used for the synthesis influenced the morphology, composition, and electrochemical behavior of the obtained Ni-Co LDHs. Moreover, atomic force microscopy (AFM) measurements revealed distinct nanoscale surface characteristics associated with the synthesis methods, with the Ni-Co LDH synthesized via the CV route exhibiting higher surface heterogeneity than that synthesized via the constant potential method (CA), resulting in a more textured surface. These findings were further supported by roughness average (Ra) values, where CV-synthesized Ni-Co LDH displayed the highest Ra of 221 nm, indicating a more extensive active surface area. The electrochemical performance, both for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), were correlated with these surface variations. This study provides valuable insights into the electrochemical experimental parameters for the synthesis of Ni-Co LDHs and their potential application in water splitting processes.Cukurova University Research FundThe authors are greatly thankful to the Cukurova University Research Fund for the financial support
Efficient recovery of Ce(III) ions from acidic solutions using oxalic acid crosslinked chitosan
No full textCerium (Ce) is widely utilized in several industrial applications and may pose health risks owing to environmental overexposure. The oxalic acid crosslinked chitosan (CHOA) adsorbent was fabricated via an eco-friendly two-step technique and employed for the Ce(III) ions adsorption from a water-based solution. The CHOA was defined by quantitative and spectroscopic examinations. The results indicate that the inclusion of oxalic acid as a cross-linking agent improved the adsorption and stability of chitosan under acidic conditions. Furthermore, it was noted that the CHOA comprised carboxylic groups, which function as functional groups for the Ce(III) ion adsorption. The maximal adsorptive ability for Ce(III) ions was ascertained to be 408.71 mg g- 1 at optimum investigational settings based on the Langmuir equation. The settings comprised a solution pH of 4, a CHOA dosage of 0.01 g, a steadiness time of 30 min, and a temperature of 300 K. Kinetic and isotherm analyses specified that the Ce(III) ions adsorption onto CHOA is most accurately designated by the pseudo-second-order and Freundlich models. Thermodynamical analysis reveals that the adsorption method was endothermic and spontaneous. The desorption percentage of Ce-loaded CHOA was approximately 40% when subjected to strong acids like HCl and HNO3. This indicates a chemical reaction between the Ce(III) cations and the functional groups on the adsorbent's surface. The primary adsorption mechanisms suggested were chelation and ion exchange. The CHOA adsorbent exhibits substantial potential for the recovery of Ce(III) cations due to its elevated adsorption potential and swift adsorption kinetics
Kaffâl eş-Şâşî el-Kebîr’in Şemâʾilü’n-Nübüvve Adlı Eserinin Muhteva Bakımından Analizi
No full textHz. Peygamber’in (s.a.s.) fizikî ve ahlâkî özelliklerini ele alan çeşitli eserler kaleme alınmıştır. Bu özellikler ilk dönemlerde hadis külliyatında “edeb, libas, et‘ime, eşribe, sıfâtü’n-nebî, menâkıb, fezâil” gibi başlıklar altında dağınık bir şekilde yer alırken, zamanla “şemâil” adıyla müstakil bir hadis literatürüne dönüşmüştür. Bu türün en erken ve en tanınmış örneği, Tirmizî’nin telif ettiği eş-Şemâʾilü’n-nebeviyye adlı eseridir. Zamanla farklı coğrafyalarda yaşayan âlimler de bu alanda eserler vermiştir. Şemâil türünde eser ortaya koyan diğer bir önemli isim Kaffâl eş-Şâşî’dir. O, Şâfiî mezhebinin Mâverâünnehir bölgesinde yayılmasına öncülük etmiştir; fakih, muhaddis, müfessir, mütekellim ve edip özellikleriyle de meşhurdur. Müellifin kaleme aldığı Şemâʾilü’n-nübüvve, 90 başlık altında 766 rivayetten oluşturulmuştur. Eserde merfû, mevkûf ve maktû haberlerle birlikte tarih kaynaklarından ve şiirlerden de istifade edilmiştir. Eserin tarih kaynakları ve şiirlerle desteklenmesi ona zenginlik kazandırmıştır. Eser, Hz. Peygamber’in fizikî özellikleri, nesebi, peygamberlik dönemi ve savaş aletleri gibi konuları detaylı biçimde yer vermiştir. Eserin genel yapısı, Tirmizî’nin Şemâʾil adlı eseriyle karşılaştırıldığında belirgin bir farklılık göstermektedir. Tirmizî, Resûlullah’ın ibadet, ahlak ve fizikî özelliklerine yoğunlaşırken; Kaffâl, Resûlullah’ın beşerî yönlerini merkeze almış ve peygamberlik özelliklerini Delâʾilü’n-nübüvve adlı eserinde işlemiştir. Bu çalışmada, Kaffâl eş-Şâşî’ye atfedilen Şemâʾilü’n-nübüvve adlı eserin değerlendirilmesi amaçlanmıştır. Eserin müellifine aidiyeti, içeriği ve hadis edebiyatındaki yeri incelenmiş; Kaffâl’ın ilmî kişiliği, eserin yapısı ve Tirmizî’nin şemâil eseriyle olan benzerlik ve farklılıkları ele alınmıştır
Capacitance-voltage, conductance-voltage and dielectric properties of the Al/GO/p-Si semiconductor structures in wide frequency range
No full textIn this study, the capacitance voltage (C-V), conductance-voltage (G/omega-V), series resistance-voltage (RS-V) characteristics, interface state densities and dielectric properties of Al/GO/p-type Si semiconductor structures were investigated in the frequency range of 100 to 1000 kHz by 100 kHz steps depending on the frequency at room temperature. Using the spin coating method, the graphene oxide (GO) solution was coated as a thin film layer on the front surface of the p-type Si semiconductor. The interface-state densities (NSS) of the Al/p-Si structures with GO interlayer decreased exponentially with bias from 3.93 x 1013 cm-2 eV-1 (for 100 kHz) to 5.07 x 1011 cm-2 eV-1 (for 1000) kHz. Furthermore, dielectric characteristics as known dielectric constant (epsilon '), dielectric loss (epsilon ''), loss tangent (tan delta), ac/dc electrical conductivity (sigma ac, sigma dc), electrical modulus (M ', M '') and complex impedance values (Z ', Z '') were obtained using C-V and G/omega-V measurements. Experimental results showed that dielectric values such as epsilon ', epsilon '', tan delta, sigma ac, sigma dc, ln sigma ac and ln sigma dc generally decreased with increasing frequency, while dielectric values such as M ', M '' Z ' and Z '' increased with increasing frequency. Accordingly, in the range of 100 kHz and 1 MHz, the values of epsilon ', epsilon '', and sigma ac, changed from 1.647 to 1.154, 54.922 to 1.422 and 3.052 x 10-9 to 7.905 x 10-10, respectively. Also, at the same frequencies, the electric modulus values M ' and M '' changed from 1.0 x 10-3 to 3.44 x 10-1 and 1.8 x 10-2 to 4.24 x 10-1, respectively.Kahramanmaras Sutcu Imam University Scientific Research Project Unit [2025/1-5 YLS]; Kahramanmaras Sutcu Imam UniversityThis work was supported by Kahramanmaras Sutcu Imam University Scientific Research Project Unit (Project numbers: 2025/1-5 YLS). We would like to thank Kahramanmaras Sutcu Imam University for financial support of the research program
Developing new models for estimating solar radiation by using Fourier series
No full textSolar energy (SE) is one of the most important energy sources. Being aware of the global solar radiation (GSR) levels in a specific region is crucial for the efficient utilization of SE. Over the years, numerous methods and approaches have been developed to estimate GSR. The accuracy of these models has been assessed using various statistical tests, and their performance or relative superiority has been widely studied. Fourier series are widely used in the analysis and solution of various engineering problems. However, a review of the literature reveals that no GSR prediction model has been developed using Fourier series. In this study, new models were developed by using the different degrees of Fourier series. The performances of all developed prediction models were examined and compared for different years in detail. The curve-fitting graphs and required calculations were made by using the Matlab program. In order to decide the success of these developed models, six different statistical metrics (R2, MPE, RPE, SSRE, t-stat and MAPE) were discussed in this article. Overall, the evaluation of the results indicates that all three models exhibit satisfactory and reliable performance. In the R2, MPE, SSRE and MAPE tests, Model 2 showed the best performance with 0.9705, 0.6187, 0.1450 and 8.4492 values, respectively. In the RPE and t-stat tests, model 3 showed the best performance with 0.7256 and 0.1751 values, respectively
Deep-Fat Frying of Chicken Nuggets: Impacts on Mass Transfer and Some Quality Indices
No full textThis study examines the impact of deep-fat frying on chicken nuggets' quality and mass transfer characteristics at three temperatures (160 degrees C, 170 degrees C, and 180 degrees C) over 180 s. Moisture diffusion coefficients, calculated as 2.74 x 10-8, 8.22 x 10-8, and 13.69 x 10-8 m2/s, respectively, indicate increasing diffusion with temperature. The activation energy (Ea) for moisture loss was found to be 128.81 kJ/mol. Initial moisture content was 0.0180 +/- 0.003 kg water/kg dry matter, reducing by 28.33%, 31.11%, and 35% for each respective temperature, ending at 0.0129 +/- 0.001, 0.0124 +/- 0.002, and 0.0117 +/- 0.002 kg water/kg dry matter. Oil uptake transfer coefficients were 0.0082, 0.0091, and 0.0094 s-1, with corresponding oil content values of 0.032 +/- 0.003, 0.029 +/- 0.003, and 0.026 +/- 0.002 g oil/100 g dry matter. Equilibrium oil content decreased, while the Ea for oil uptake was -35.63 kJ/mol. Textural properties showed increases in hardness (129.88 +/- 0.84 to 131.34 +/- 0.56 mJ), springiness (4.28 +/- 0.12 to 4.37 +/- 0.12 mm), and chewiness (84.54 +/- 0.56 to 85.65 +/- 0.65 mJ) with temperature, while cohesiveness remained stable. Color measurements showed a brightness (L*) value decrease of up to 15.73% at 180 degrees C and a total color change (Delta E) increase from 4.78 +/- 0.55 at 160 degrees C to 9.31 +/- 0.76 at 180 degrees C. This data provides a foundation for optimizing frying parameters to improve product quality and consistency in the food industry. Future research may explore the use of novel coating formulations or alternative frying media to minimize oil absorption while preserving desirable texture and flavor attributes
Energy efficiency and cost analysis with economizer in industrial systems
No full text09.03.2026 tarihine kadar kullanımı yazar tarafından kısıtlanmıştır.Bu tez çalışması, endüstriyel sistemlerde ekonomizer kullanımının enerji verimliliği ve maliyet analizi üzerindeki etkilerini kapsamlı bir şekilde incelemektedir. Çalışmanın temel amacı, farklı optimizasyon yöntemlerinin ekonomizer yatırımlarının finansal geri dönüş süreleri ve operasyonel performansları üzerindeki etkilerini belirlemektir. Bu doğrultuda, bir işletmedeki ekonomizerin optimum boyutlarının belirlenmesi, gerekli pompa ve fan gücünün hesaplanması, maliyet analizleri ve yatırımın geri dönüş süresinin tespiti için matematiksel bir model geliştirilmiştir. Yapılan analizler sonucunda, OPTY2 optimizasyon yönteminin tüm kriterler (PEC1, PEC2, PEC3, PEC4) altında yüksek ilk yatırım maliyetleri ve uzun toplam geri dönüş süreleri (4,82 Ay ilk geri dönüş, 13,58 Ay toplam geri dönüş) sergilediği tespit edilmiştir. Bu bulgu, OPTY2 yönteminin diğer optimizasyon yaklaşımlarına kıyasla daha az maliyet etkin olduğunu göstermektedir. Geri dönüş süresi analizi, endüstriyel ekonomizer sistemlerinin finansal cazibesini belirlemede kritik bir faktör olarak öne çıkmaktadır. Eğer birincil hedef yatırımın en kısa sürede geri kazanılması ise, PEC1 veya PEC4 kriterleri altında OPTY3 optimizasyon yönteminin tercih edilmesi en uygun yaklaşım olarak belirlenmiştir. Buna karşılık, belirli bir performans veya verimlilik seviyesine ulaşmanın daha öncelikli olduğu durumlarda (örneğin PEC2 kriteri), yatırımın uzun vadeli faydaları ve stratejik hedefler göz önünde bulundurulmalıdır. Bu tez çalışması, endüstriyel ekonomizer yatırımları için bilinçli karar verme süreçlerine katkı sağlayacak değerli bilgiler sunmaktadır. Elde edilen bulgular, enerji verimliliği projelerinin planlanması ve uygulanması aşamalarında maliyet etkinliğin ve stratejik önceliklerin dengelenmesinin önemini vurgulamaktadır. Anahtar Kelimeler: Ekonomizer, Enerji Verimliliği, Maliyet Analizi, Geri Dönüş Süresi, Optimizasyon, Endüstriyel Sistemler.This thesis comprehensively examines the effects of economizer usage on energy efficiency and cost analysis in industrial systems. The main objective of the study is to determine the effects of different optimization methods on the financial payback periods and operational performances of economizer investments. In this context, a mathematical model has been developed to determine the optimal sizes of an economizer in a business, calculate the necessary pump and fan power, conduct cost analyses, and identify the payback period of the investment. As a result of the analyses conducted, it was determined that the OPTY2 optimization method exhibited high initial investment costs and long total payback periods (4.82 months for initial payback, 13.58 months for total payback) under all criteria (PEC1, PEC2, PEC3, PEC4). This finding indicates that the OPTY2 method is less cost-effective compared to other optimization approaches. Return on investment analysis emerges as a critical factor in determining the financial attractiveness of industrial economizer systems. If the primary goal is to recover the investment in the shortest time possible, the OPTY3 optimization method under the PEC1 or PEC4 criteria has been determined to be the most suitable approach. Conversely, in cases where achieving a specific level of performance or efficiency is more prioritized (for example, under the PEC2 criterion), the long-term benefits of the investment and strategic goals should be taken into account. This thesis provides valuable insights that will contribute to informed decision-making processes for industrial economizer investments. The findings emphasize the importance of balancing cost-effectiveness and strategic priorities during the planning and implementation phases of energy efficiency projects. Keywords: Economizer, Energy Efficiency, Cost Analysis, Payback Period, Optimization, Industrial Systems
RESTORANLARDA ROBOT GARSONLARIN KULLANIMINA YÖNELIK TOPLUMSAL ALGILAR: SOSYAL MEDYADA DUYGU VE İÇERİK ANALİZİ
No full textIn this study, it is aimed to determine the opinions of online user comments written on videos about robot waiters used in restaurants on the YouTube platform. For this purpose, online user comments on the top fifteen most commented YouTube videos about service robots and robot waiters used in restaurants were analyzed through sentiment analysis and content analysis. In sentiment analysis, a Lexicon (NLP)-based approach was used to polarize the comments into positive, neutral, and negative sentiments. To support the results of sentiment analysis, MAXQDA was used in the content analysis method. According to the results of the analysis, 37.1% of user comments were positive, 32.5% were negative, and 30.4% were neutral. This study is particularly important given that the implementation of robot waiters in restaurants is still in its infancy, as online reviews contribute to the understanding of new services and entities. Methodologically, this research offers an innovative approach, such as sentiment analysis, in determining society's acceptance and opinion of technology in robot-human interaction. The findings are considered important as they will provide theoretical contributions to the literature and practical contributions to sectoral applications.Bu çalışmada restoranlarda robot garsonların kullanımına yönelik toplumsal görüşü çevrimiçi kullanıcı yorumları ile belirlenmesini amaçlamaktadır. Bu amaç kapsamında, restoranlarda kullanılan hizmet robotları ve robot garsonlarla ilgili en çok yorum alan ilk on beş YouTube videosundaki çevrim içi kullanıcı yorumları duygu analizi ve içerik analizi yöntemiyle incelenmiştir. Duygu analizinde, Lexicon (NLP) tabanlı bir yaklaşım kullanılarak yorumlar olumlu, nötr ve olumsuz olarak duygu kutupları belirlenmiştir. Duygu analizinin sonuçlarını desteklemek için ise içerik analizi yönteminde MAXQDA kullanılmıştır. Analiz sonuçlarına göre, kullanıcı yorumlarının %37,1’i olumlu, %32,5’i olumsuz ve %30,4’ü nötr olarak belirlenmiştir. Bu çalışma özellikle robot garsonların restoranlarda uygulanmasının henüz yeni olduğu göz önüne alındığında, çevrim içi yorumlar yeni hizmetlerin ve oluşumların anlaşılmasına katkı sağlaması bakımından önemlidir. Metodolojik olarak bu araştırma robot-insan etkileşiminde toplumun teknoloji kabulü ve görüşünün belirlenmesinde duygu analizi gibi yenilikçi bir yaklaşım sunmaktadır. Elde dilen bulguların ise, alan yazına teorik, sektörel uygulamalara ise pratik katkılar sunması açısından önemli görülmektedir
Solar-assisted radiant heating system with nano-B4C enhanced PCM for nearly zero energy buildings
No full textThis investigation centers on the design and performance of a solar-assisted domestic radiator optimized for nearly zero-energy buildings (nZEBs), combining experimental and numerical approaches. The system is powered by a Photovoltaic/Thermal (PV/T) collector, customized to the climatic specifics of Elazig, Turkey. The study introduces nano-enhanced Phase Change Materials (NEPCM) embedded with Boron Carbide (B4C) nanoparticles to improve efficiency. The NEPCM demonstrating the highest thermal conductivity and specific heat capacity, was selected for numerical analysis. These NEPCM were strategically integrated into the radiator system to maintain ambient room temperatures without additional energy input, particularly during non-solar periods like nighttime. The analysis, conducted under turbulent flow conditions using the finite volume method, reveals that NEPCM significantly improves indoor temperature regulation. The most notable temperature differential, 2.82 K, was observed between configurations with and without PCM. However, the comparison between NEPCM and pure PCM with halved thickness shows a minimal temperature difference of 0.62 K, indicating a slight improvement due to nanoparticle inclusion. These findings highlight both the potential benefits and the limitations of integrating NEPCM into domestic heating systems for sustainable building applications.Fimath;rat University Scientific Research Unit FUBAP [TEKF 24.24]Authors thanks to F & imath;rat University Scientific Research Unit FUBAP to support the study with TEKF 24.24