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Infusion times and temperature on the composition of tea beverages
No full textTea composition is significantly affected by different infusion times and temperatures during preparation. Tea's antioxidant capacity, phenolics, antibacterial activity, mineral content, aroma, and sensory properties change significantly depending on these conditions. The amount of compounds dissolved in tea can be influenced by brewing time and temperature, which can increase antioxidant and antibacterial capacity. Longer infusion times and higher temperatures extract more antioxidants and antibacterial compounds from the tea but can also alter the sensory properties of the tea. Short infusion times and low temperatures produce a delicate aroma and taste, while longer and higher temperatures yield a more intense aroma and flavor profile. Understanding how brewing time and temperature affect tea's antioxidant capacity, phenolic compounds, antibacterial activity, mineral content, aromas, and sensory properties can assist tea consumers in creating teas with the desired flavor and aroma characteristics. This chapter evaluates the effects of infusion times and temperature on tea composition. © 2025 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies
Evaluating the performance of Bi58Sn42 mold produced by material extrusion additive manufacturing system for agile manufacturing
No full textPurposeThe purpose of this study is to produce a low-cost sheet metal forming mold made from the low melting point Bi58Sn42 (bismuth) alloy by using an open-source desktop-type material extrusion additive manufacturing system and to evaluate the performance of the additively manufactured mold for low volume sheet metal forming. Thus, it was aimed to develop a fast and inexpensive die tooling methodology for low-volume batch production.Design/methodology/approachInitially, the three-dimensional printing experiments were performed to produce the sheet metal forming mold. The encountered problems during the performed three-dimensional printing experiments were analyzed. Accordingly, both tunings in process parameters (extrusion temperature, extrusion multiplier, printing speed, infill percentage, etc.) and customizations on the extruder head of the available material extrusion additive manufacturing system were made to print the Bi58Sn42 alloy properly. Subsequently, the performance of the additively manufactured mold was evaluated according to the dimensional change that occurred on it during the performed pressing operations.FindingsResults showed that the additively manufactured mold was rigid enough and proved to have sufficient strength in sheet metal forming operations for low-volume production.Originality/valueAlternative mold production was carried out using open-source material extrusion system for low volume sheet metal part production. Thus, cost effective solution was presented for agile manufacturing.Scientific Research Projects Coordination Unit (BAP) of Cukurova University in Adana, Turkey [FDK-2015-4349]The study was supported by the Scientific Research Projects Coordination Unit (BAP) of Cukurova University in Adana, Turkey for the financial support provided under grand No: FDK-2015-4349
Minimum Distance and Minimum Time Optimal Path Planning With Bioinspired Machine Learning Algorithms for Faulty Unmanned Air Vehicles
No full textUnmanned air vehicles operate in highly dynamic and unknown environments where they can encounter unexpected and unseen failures. In the presence of emergencies, autonomous unmanned air vehicles should be able to land at a minimum distance or minimum time. Impaired unmanned air vehicles define actuator failures and this impairment changes their unstable and uncertain dynamics; henceforth, path planning algorithms must be adaptive and model-free. In addition, path planning optimization problems must consider the unavoidable actuator saturations, kinematic and dynamic constraints for successful real-time applications. Therefore, this paper develops 3D path planning algorithms for quadrotors with parametric uncertainties and various constraints. In this respect, this paper constructs a multi-dimensional particle swarm optimization and a multi-dimensional genetic algorithm to plan paths for translational, rotational, and Euler angles and generates the corresponding control signals. The algorithms are assessed and compared both in the simulation and experimental environments. Results show that the multi-dimensional genetic algorithm produces shorter minimum distance and minimum time paths under the constraints. The real-time experiments prove that the quadrotor exactly follows the produced path utilizing the available maximum rotor speeds.Scientific and Technological Research Council of Turkey (TBIdot;TAK)No Statement Availabl
Production of NiCoMo-Supported Ni Foam for Electrocatalytic Oxidation of Methanol: Experimental and RSM Analysis
No full textThe Ni-, Co-, and Mo-supported Ni foam (NiF-NiCoMo) was produced via galvanostatic method, and electrooxidation of methanol in alkaline medium was examined. The characterization was achieved using field emission scanning electron microscopy, energy-dispersive X-ray, and X-ray diffraction analysis. The electrochemical behavior was determined via cyclic voltammetry and chronoamperometry analysis. The contribution of each transition metal to electrocatalytic performance of NiF was monitored via mono, binary, and ternary modifications of each transition metal (Ni, Co, and Mo) for several amounts (5, 10, and 15 mu g). Experiments were performed to determine the influence of catalyst amounts, methanol concentration, and scan rate parameters. The impacts of independent parameters on methanol electrooxidation were statistically investigated using Design-Expert software. The ability to analyze multiple parameters with a limited number of experimental performances is one of the method's key benefits. The developed model showed that 9.41 and 14.03 mu g catalyst amounts were the appropriate values for NiF-NiMo and NiF-NiCoMo achieving optimal circumstances, respectively.Scientific and Technological Research Council of Turkiye (TUB ITAK)Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUB ITAK)
Does Consumers' Cultural Background Affect How They Perceive and Engage in Food Sustainability? A Cross-Cultural Study
No full textMotivated by the evolving global food landscape and its detrimental impacts on society, the environment, and health, this research aims to understand consumer perceptions, preferences and involvement regarding sustainable food products and consumption practices. To this aim, three countries were chosen for their distinct economic, cultural, and demographic differences (Spain, Turkiye, and Colombia), enabling an exploration of how these factors influence sustainability perceptions. The results show high levels of awareness, knowledge, consumption, and willingness to switch to more sustainable habits, although differences between countries were also found (price sensitivity in Spain and demand for information regarding sustainable food in Colombia). In addition, a group of consumers has been identified that is influenced by health, shows positive behaviours and perceptions towards sustainable food, and is not price sensitive. The study is significant, as it addresses the information gap between consumers, producers, and policymakers regarding sustainable food awareness. It seeks to provide insights into cultural influences on sustainability perceptions and aims to assist in developing educational programs and policies to promote sustainable consumption.Universidad del MagdalenaNo Statement Availabl
A Case Study of Nelder Mead Simplex Optimization Algorithm: Trade-Offs of Sprienski Fractal Bowtie Antenna Parameters
No full textIn this study, tri-band antenna design adapted for wireless communication, Internet of Things (IoT) and RFID systems is examined. The simulation results indicate that the proposed antenna has three distinct frequency bands. Band 1 (lower band) covers the frequency range of 1.64-1.78 GHz with a resonance frequency of 1.7 GHz. Band 2 covers the range of 3.06-3.9 GHz with a resonance frequency of 3.4 GHz with a high gain of 10 dBi and a radiation efficiency of 92% for long-range communication. Band 3 radiates from 6.25 to 7.6 GHz with a resonance frequency of 6.62 GHz, which is suitable for higher-frequency applications. The antenna design is simulated and analyzed regarding S11, VSWR, gain, radiation efficiency, and bandwidth. Especially, Band 2 (mid-band) provides notable performance, with its 10 dBi gain and 92% efficiency, which makes the proposed antenna an ideal structure for high-data-rate, long-distance communication systems, and 5G (midband) applications. This study also employs the Nelder-Mead Simplex algorithm to observe the optimization of the physical parameters of the proposed antenna via multiple objective functions. The optimization results outlines that longer the arm length of the proposed antenna causes to decrease the resonance frequency of Band 3. Addition to this, the gain is higher with the lower arm length except for the arm length of 90.467 mm and flare angle of 64.77o. That’s, the trade-off condition occurs between minimum return loss and gain. At this point, it can be concluded from this optimization algorithm results that each objective function should be evaluated separately due to this trade-off condition
Intergenerational occupational mobility in Latin American economies: An empirical approach
No full textIdentifying the determinants of intergenerational mobility is an important aim in the development literature. In this article, we examine intergenerational transmission for 6 neglected Latin American Economies (Brazil, Costa Rica, Ecuador, Mexico, Panama and Puerto Rico). We use a multinomial logit model of the determinants of choosing a white-collar job for the child of a father working in farming as compared to a child whose father had a blue- or white-collar job. We find that, in the studied countries, intergenerational occupation transmission is mainly linked to low skilled jobs. Our analysis confirms the low degree of social mobility typical of Latin America, in turn contributing to explaining the low growth rate. Our findings help identify specific target groups - talented young women coming from the agricultural sector - for developing soft skills while at primary or low secondary school and work -related skills while at high secondary school or university
Community interpreting in Türkiye: Diversifying needs and responses at the center of dynamic movements of migration
No full textTürkiye, with its geographically and geopolitically strategic location as a transit route between Asia, Europe and Africa continents and as a country neighboring to Middle Eastern countries in a state of constant turmoil, has recently become an important destination in terms of international migration. Globalization processes and economic developments especially in the 2000s have also contributed to the diversified migrant profiles of Türkiye. Practices of community interpreting, a means of facilitating communication between migrants and host communities in public and social services, have diversified in the same direction in Türkiye over the years. Community interpreting, which gained momentum in Türkiye with emergency and disaster interpreting following the earthquakes in the Marmara Region in 1999, has become a service area including multiple stakeholders in a wide variety of public, social and state institutions for migrants of different profiles, such as Syrian, Iraqi, Afghan, Ukrainian refugees; German, Russian, British tourists; or incoming foreign patients within the scope of health tourism. This study focuses on how migration movements in recent years and the needs of various migrant groups have shaped community interpreting practices in Türkiye. Treating community interpreting as a social practice with its diversifying target audiences, stakes, stakeholders and actors, the study discusses the development dynamics of community interpreting in Türkiye on the basis of its professional, institutional and academic status. © 2024 Peter Lang Group AG, Lausanne. All rights reserved
Penetration mechanics of ceramic/metal functionally graded plates under ballistic impact: An experimental perspective
No full textThis paper deals with a comprehensive experimental analysis of the penetration mechanics and failure mechanisms of SiC/AA6061 functionally graded plates under ballistic impact. The external, cross-sectional, and highspeed photographic damage and failure assessments of the plates were performed. The novelty of this study is to investigate the ballistic impact behavior of a ceramic/metal functionally graded plate with different compositional gradients in a wide range of impact velocities considering below and above the ballistic limit and to reveal a detailed analysis of the damage and failure mechanisms of the plate. This can provide fundamental insights into the design of ceramic/metal functionally graded armor materials. The results indicate that the metal-dense gradient plate shows localized ductile failures as ductile perforation and plugging, whereas the ceramic-dense gradient plate exhibits brittle failures as comminution and conoidal fracture. Tailoring a relatively continuous compositional gradient instead of an abrupt variation, namely the linear gradient, provides tensile stress wave attenuation and resistance to crack growth and fracture
CRITIC tabanlı TOPSIS ve PROMETHEE II yöntemleri ile optimal okul yeri seçimi: Kilis ili örneği
No full textFen Bilimleri Enstitüsü, Endüstri Mühendisliği Ana Bilim DalıÇalışmamızda 6 Şubat Kahramanmaraş depreminden etkilenen 11 ilden biri olan Kilis ili Merkez ilçesinde depremden ağır hasar alarak yıkımı gerçekleştirilen okulların yeniden yapılması için okul yeri seçimi problemi ele alınmıştır. Yapılan incelemeler sonucunda ortaokul seviyesindeki okul sayısının potansiyel öğrenci nüfusunu karşılayamayacak durumda olduğu tespit edilmiş olup bundan dolayı çalışma amacı açılması planlanan ortaokul için en uygun yerin seçilmesi olarak kararlaştırılmıştır. Okul yeri seçimi yapılırken birçok kriterin birlikte değerlendirilmesi gerektiğinden dolayı çok kriterli karar verme yöntemlerinden Kriterler arası Korelasyon Yoluyla Kriterlerin Önem Tespiti ( CRITIC), İdeal Çözüme Benzerliğine Göre Tercih Sıralama Tekniği (TOPSIS) ve Tercih Sıralaması Organizasyonu Değerlendirme Zenginleştirme Yöntemi (PROMETHEE II)yöntemleri uygulanmıştır. Çalışmada ilk olarak Kilis ilinde ortaöğretim kademesi için eğitim alanı olarak tahsis edilen araziler tespit edilmiş ve bu araziler çalışmanın alternatif verileri olarak kullanılmıştır. Kriter tespiti için uzman görüşleri ve literatürdeki çalışmalardan faydalanılmış ve belirlenen kriterlerin ağırlıkları CRITIC yöntemi ile hesaplanmış ve alternatif eğitim alanı olarak tahsis edilen araziler TOPSIS ve PROMETHEE II yöntemleri ile sıralanmış ve bu iki yöntemin sonuçları karşılaştırılmıştır. Çalışmada okul yeri seçiminde 5 alternatif eğitim tahsis alanı için 5 farklı kriter değerlendirilmiştir. Sonuç olarak erişilebilirlik kriteri en önemli kriter seçilmiş ve TOPSIS yöntemi sonucuna göre Rıfat Kazancıoğlu eğitim tesis alanı ,PROMETHEE II yöntemi sonucuna göre de Kazım Karabekir eğitim tesis alanı en iyi alternatif olarak belirlenmiştir.In our study, the problem of school site selection for the reconstruction of schools that are heavily damaged and demolished in Kilis province, which is one of the 11 provinces affected by the February 6 Kahramanmaraş earthquake is handled. As a result of the investigations, it has been determined that the number of schools at the secondary school level cannot meet the potential student population, and therefore, the purpose of the study is to select the most suitable location for the reconstruction of a secondary school. Since many criteria should be evaluated together in the selection of, the Criteria Importance Determination Through Correlation Between Criteria (CRITIC) is used for determining weights of the criteria and then ,The Preference Ranking Technique According to Similarity to Ideal Solution (TOPSIS) methods, and The Preference Ranking Organization Method for Enrichment Evaluation which are multi-criteria decision-making methods, were applied for site selection. In the study, firstly, the lands allocated as educational areas for secondary education in Kilis province were determined and these lands were used as alternative data of the study. For the determination of criteria, expert opinions and studies in the literature were used and the weights of the determined criteria were calculated with the CRITIC method and the lands allocated as alternative educational areas were ranked with the TOPSIS and PROMETHEE II methods and the results of these two methods were compared. In the study, 5 different criteria were evaluated for 5 alternative educational allocation areas in the school site selection. As a result, the accessibility criterion was selected as the most important criterion and according to the TOPSIS method result, the Rıfat Kazancıoğlu educational facility area was determined as the best alternative and according to the PROMETHEE II method result, the Kazım Karabekir educational facility area was determined as the best alternative