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Forecasting ground-level ozone and fine particulate matter concentrations at Craiova city using a meta-hybrid deep learning model
No full textAir quality forecasting is vital for managing and mitigating the adverse effects of air pollution on human health, crops, and the environment. This study aims to forecast daily time series of ozone and fine particulate matter (PM) concentrations using a meta-hybrid deep NARMAX (Nonlinear Auto-Regressive Moving Average with eXogenous inputs) model. Two datasets were utilised: (a) data on meteorological parameters (temperature, air pressure, relative humidity) and air pollutant concentrations (particulate matter, ozone, dioxide of carbon, volatile organic compounds, formaldehyde) provided by a sensor model A3 situated in the centre of Craiova city, and (b) data on wind direction, wind speed, and sunshine duration provided by the National Meteorological Administration. The data sets covered a time interval from December 10, 2020, to January 05, 2024. Initially, a statistical analysis was conducted to assess the correlation between variables. Results revealed that ozone concentration is primarily influenced by meteorological variables such as temperature (r = 0.79), sunshine duration (r = 0.55), and relative humidity (r = -0.48), and secondarily by air pollution indicators including VOC (r = -0.34), PM concentrations (r = -0.34), and CO2 (r = -0.3). In the subsequent stage, thirteen Machine Learning (ML) models were employed in conjunction with an integral feature selection (IFS) method to identify the best combinations of predictor variables for predicting ozone and PMs. Finally, a deep NARMAX model was developed to forecast the next periods of ozone and PMs based on the optimal combinations identified earlier. Results indicated the selection of sixty best models for ozone forecasting and four best models for PMs. The R-2 values surpassed 0.97 for ozone and exceeded 0.8 for PMs, demonstrating the efficacy of the forecasting approach.That is a statement of declaration by the authors indicating that they do not have any financial or personal relationships that could potentially influence the results or interpretation of their work. This declaration is a common practice in research papers to ensure transparency and credibility of the reported results
A finite element approach for addressing the interphase modulus and size interdependency and its integration into micromechanical elastic modulus prediction in polystyrene/SiO2 nanocomposites
No full textThe perturbed transitional area between the nanoparticle and matrix shapes the properties of polymer nanocomposites. Due to the stochastic nature of these interphase regions, their size and physical properties are intricately linked. For instance, a higher interphase modulus, Eint, might result from a thinner interphase, and vice versa. The inherent randomness can introduce variability in the interphase modulus with respect to interphase thickness, tint. This challenges the practicality of conventional micromechanical approaches, which assume the interphase modulus to be either a constant or a function of filler and matrix properties when predicting the elastic modulus of polymer nanocomposites. Unlike conventional approaches, which simply used interphase quantification to predict global stiffness and treated the interphase modulus independently of its thickness, this study aims, for the first time, to consider the stochastic nature of the interphase, seeking to exclusively explore the interdependencies within the Eint - tint relationship in polystyrene/SiO2 nanocomposites. Simulations were conducted using finite element analysis, FEA, providing high accuracy and flexibility. To manage the large number of simulations, FEA was streamlined with a customized Python scripting, generating a spectrum of (Eint, tint) solutions for varying SiO2 contents based on experimental measurements and a rigorous methodology. Subsequently, empirical equations were formulated, unveiling the relationship between Eint and tintper composition. The FEA-driven interphase intercorrelation scheme was compared to the results obtained from a modified three-phase Halpin-Tsai model. Additionally, the FEA scheme was utilized to modulate the HT model by adjusting its relevant interphase terms
Deep Learning-Based Prediction Models for the Detection of Vitamin D Deficiency and 25-Hydroxyvitamin D Levels Using Complete Blood Count Tests
No full textVitamin D (VitD) is an essential nutrient that is critical for the well-being of both adults and children, and its deficiency is recognized as a precursor to several diseases. In previous studies, researchers have approached the problem of detecting vitamin D deficiency (VDD) as a single ”sufficient/deficient” classification problem using machine learning or statistics-based methods. The main objective of this paper is to predict a patient’s VitD status (i.e., sufficiency, insufficiency, or deficiency), severity of VDD (i.e., mild, moderate, or severe), and 25-hydroxyvitamin D (25(OH)D) level in a separate deep learning (DL)-based models. An original dataset consisting of complete blood count (CBC) tests from 907 patients, including 25(OH)D concentrations, collected from a public health laboratory was used for this purpose. CNN, RNN, LSTM, GRU and Auto-encoder algorithms were used to develop DL-based models. The top 25 features in the CBC tests were carefully selected by implementing the Extra Trees Classifier and Multi-task LASSO feature selection algorithms. The performance of the models was evaluated using metrics such as accuracy, F1-score, mean absolute error, root mean square error and R-squared. Remarkably, all three models showed satisfactory results when compared to the existing literature; however, the CNN-based prediction models proved to be the most successful. © 2024, Publishing House of the Romanian Academy. All rights reserved
Haber Sitelerinin Mobil Görünümleri: Örnek Bir İnceleme
No full textİletişim teknolojilerindeki gelişmeler ve internet kullanımın artması sonucunda ortaya çıkan ve toplumda yaygın bir şekilde kullanılmaya başlayan mobil aygıtlar, insanlar tarafından habere ulaşmada kullanılan başat araçlardan biri konumuna gelmiştir. Medya kuruluşları okuyucularının beklentilerini karşılama ve iyi anlaşılma adına içeriklerini yayımlayacağı ortamları etkili şekilde hazırlamak zorundadır. Bu noktada habercilik açısından tasarımın önemi ortaya çıkmaktadır. Temel tasarım ilkeleri ve web tasarım öğeleri etkili sayfalar oluşturmak adına kritik role sahiptir. Bu araştırmada da Türkiye’de en çok okuyucu sayısına sahip olan ilk 5 haber sitesinin Hürriyet, Milliyet, Mynet, Sözcü ve Sabah’ın mobil görünümlerinin ana sayfaları tasarım ilkeleri ve web tasarım öğeleri kapsamında içerik analizi yöntemi kullanılarak detaylı bir şekilde incelenmiştir. Çalışma Türkiye’de yayım yapmakta olan mobil haber sitelerinin tasarımsal boyutunu bütüncül bir şekilde ele alması bakımından önemlidir. Araştırma sonucu elde edilen bulgular, mobil site tasarımlarında, tasarım ilkelerinin ve web tasarım elemanlarının doğru ve yanlış kullanımlarını ortaya koymuştur. İncelenen mobil haber sitelerinde temel grafik tasarım ilkelerinin önemli bir oranda uygulanmaya çalışıldığı tespit edilmiştir. Web tasarım öğelerinin kullanımı açısından elde edilen bulgulara bakıldığında ise mobil sitelerde görsel, renk, tipografi kullanımı açısından farklılıkların olduğu belirlenmiş, bu farklılıkların her bir sitenin kendi görsel kimliğini oluşturmasında önemli bir işlevi yerine getirdiği görülmüştür
Experimental and numerical investigation of a solar thermocline system for domestic water heating applications
No full textSolar energy is one of the major sources of renewable energy and is being extensively harnessed. However, the intermittent nature limits solar energy to act as a stand-alone energy source. Therefore, it becomes imperative that effective and economical methods of storing solar energy on a large scale are developed. Both sensible and latent heat storage methods are available. The use of a thermal energy storage (TES) system is an attractive choice for high-temperature applications such as power generation plants. The present study investigates the development of a small-scale TES system using a concentrated solar collector. For this purpose, a small cylindrical thermocline tank with suspended copper pipes in the storage medium was developed, with vegetable oil working as the heat transfer fluid (HTF) and being circulated through the pipes to transfer heat to used engine oil as the storage medium. A pump continuously circulates the HTF through the charging loop. TES was designed and developed based on the results of numerical simulations before the physical development of the experimental setup. Numerical calculations were performed for determining heat transfer and charging characteristics using different heat storage materials. The numerical results showed that a maximum temperature of 67 degrees C was achieved in the 100-min simulation while in the experimental results, a maximum temperature of 64 degrees C was achieved. The experimental results were found in close conformance with the simulation results. The experiments showed that the flow rate of 0.088 L s-1 was optimal and provided the highest temperature in the thermocline tank. The discharging experiment showed that the apparatus is viable to be used for 5.5 h for heating purposes. The salient feature of the study is an inexpensive TES system development and can act as a benchmark for the future development of renewable technology.Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi [23460]; KPK, PakistanThe authors acknowledge the support of the Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, 23460, KPK, Pakistan, and its Interdisciplinary Engineering, Modelling and Simulation Research Group (IEMSRG) in carrying out the present research work
Assessing the safety and reliability of type-3 high-pressure composite tanks: a comprehensive analysis of failure metrics
No full textPressure tanks play a pivotal role in various industrial applications, serving as vessels for the storage of gases under different pressures and environmental conditions. The burgeoning interest in hydrogen gas as a clean energy source has necessitated a comprehensive assessment of pressure tank structural integrity, particularly under high-pressure demands exceeding 700 bar. In this study, we systematically investigate the influence of different aluminum alloys, including AL6061, AL7075, and AL7178, reinforced with various fiber/epoxy composite materials. Our primary objective is to identify the optimal combination of liner and composite materials, along with the number of composite layers and fiber winding orientations that minimize distortion energy within the tank's liner and composite layers while maximizing safety factors. Our results indicate that distortion energy decreases as the fiber angle increases from zero to 75 degrees, with the ideal fiber orientation angle shifting with the number of composite layers. The lowest distortion energy levels in the liner were achieved in composite tanks comprising 60 laminates of reinforcing composite material, wound at an orientation angle of [+/- 55 degrees/90 degrees]. Across various internal pressure levels, pressure tanks reinforced with boron/epoxy composite material consistently outperformed other fiber materials. In terms of aluminum liner materials, AL6061 exhibited a remarkable 10.5% reduction in distortion energy on average when compared to AL7075. Safety indices revealed that pressure tanks reinforced with aramid/epoxy composite material provided the highest level of reliability, particularly when applying the maximum principal stress criterion. Carbon/epoxy and graphite/epoxy composites followed closely. In contrast, glass/epoxy and Kevlar/epoxy composites did not meet the stringent safety requirements for high-pressure storage tanks. These findings offer invaluable guidance for designing high-pressure composite tanks, ensuring their structural integrity and safety when storing hydrogen gas at elevated pressures, and exemplify the importance of materials and design considerations for such critical applications.Scientific Research Coordination Unit of Adana Alparslan Turkes Science and Technology University [23103004]This work was supported by Scientific Research Coordination Unit of Adana Alparslan Turkes Science and Technology University with project number of 23103004
Supply-Chain Resilience and Risk Management in the Post-COVID Era
No full textNatural disasters such as earthquakes, anthropogenic hazards such as terrorism, or pandemic diseases such as COVID-19, which affect the whole world in every aspect, have caused businesses and supply chains to be adversely affected throughout history. In this way, unpredictable and unpreventable conditions have forced businesses and decision-makers to develop strategies and act with multiple alternatives to take precautions. With the COVID-19 outbreak, the high dependence of countries, industries and businesses on their suppliers and the extent to which interruptions cause disruptions have shown themselves with brutal consequences. In this study, by focusing on the literature and real case studies, the disruptions experienced by supply chains during the COVID-19 period are discussed, and the measures taken to improve supply-chain resilience against disruptions after the pandemic are evaluated. Thus, by analysing the case studies obtained through six semi-structured interviews with supply-chain businesses from various industries, the lessons learned from the COVID-19 experiences have revealed the practices that can respond quickly to change, make more functional decisions at times of risk, and take more robust steps in the event of a different disruption in the future, on the purpose of developing supply chain resilience. © 2025 selection and editorial matter, Shilpa Deo and Fatma Feyza Gündüz; individual chapters, the contributors
Structural and shielding effectiveness properties of (NiFe2O4/chopped strands) composites for 6.5-18 GHz applications (vol 35, 1407, 2024)
No full text[Abstract Not Available]Scientific Research Projects Coordination Unit (BAP Unit) at Adana Alparslan Tuerkes Science and Technology University [22101001]In the Acknowledgements section of this article, the project number 22101001 relating to Adana Alparslan Tuerkes Science and Technology University-BAP Unit was missed to incorporate. The complete Acknowl- edgement section is given below.This work has been edited in memorial of Salim Sahin and Emsal Sahin, Prof. Dr. Ayhan Mergen. We thank Istanbul Technical University and for the support by Scientific Research Projects Coordination Unit (BAP Unit) at Adana Alparslan Tuerkes Science and Technology University with project number 22101001
Effect of sainfoin (Onobrychis viciifolia Scop.) seed-based diet on rats: A comprehensive evaluation of hemogram, biochemistry, and histopathology
No full textSainfoin species (Onobrychis spp.) have been employed for centuries as an essential forage for ruminant animals, both for grazing and as hay. The seeds produced by sainfoin have also been investigated as an animal feed source and were indicated to be a particularly protein-rich supplement for monogastric animals. This study explores the effects of two sainfoin seed inclusion rates in rat diets compared to a control diet, focusing on blood biochemical parameters and a comprehensive histopathological evaluation of multiple organ systems. Thus, we provide a novel contribution to the body of evidence investigating sainfoin seeds as a protein supplement in monogastric animal diets. In this 21-day experiment, seven rats each were assigned to the control group, a 5% sainfoin seed group, and a 10% sainfoin seed group. The control group received standard feed and water; the second group received feed with 5% sainfoin seeds; and the third group received feed with 10% sainfoin seeds. At the experiment's end, necropsies and evaluations were conducted. Histopathological exams revealed normal organ structures in all 21 samples, regardless of the group. Blood analysis showed statistically significant decreases in creatine, ALT, P, Ca, and Mg levels in the sainfoin seed groups compared to the control group, with most values nearing reference levels, suggesting potential benefits. Notably, no adverse effects were observed when sainfoin seeds were included at 5% and 10% in the rat feed. These findings contribute to a growing body of research investigating the inclusion of sainfoin seeds in monogastric animal diets, which is a foundational component of assessing sainfoin's potential as a novel pulse crop for human consumption.Scientific and Technological Research Council of Turkey (TUBITAK)None
Polysaccharides from shell waste of shellfish and their applications in the cosmeceutical industry: A review
No full textShell waste from shellfish processing contains valuable natural polysaccharides, including sulfated polysaccharides, acidic polysaccharides, glycosaminoglycans, chitin and their derivatives. These shellfish wastederived polysaccharides have numerous functional and biological properties that can be applied in various industries, including the cosmeceutical industry. In keeping with global sustainability and green industry trends, the cosmeceuticals industry is transitioning from petrochemical-based ingredients to natural substitutes. In this context, shell waste-derived polysaccharides and their derivatives can play a major role as natural substitutes for petroleum-based components in various cosmeceutical skincare, hair care, oral care and body care products. This review focuses on the presence of polysaccharides and their derivatives in shell waste and discusses their various cosmeceutical applications in skin care, hair care, sun care, oral care and body care products. This indicates that shell waste utilization will help create a circular economy in which extracted polysaccharides are used to produce green cosmeceutical products.Mahidol University, ThailandThis research project was supported by Mahidol University, Thailand. The authors would like to thank Arabella Fiona Palladino for the English language editing of the article