Sakarya University of Applied Sciences AXSIS
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Physical and Mechanical Properties of Mycelium-based Insulation Materials Produced from Desilicated Wheat Straws - Part A
No full textMycelium-based insulation materials made from lignocellulosic resources have the potential to replace petroleum-based foams. In this study, desilicated wheat straw was inoculated with Pleurotus ostreatus (PO) and Ganoderma lucidum (GL) fungi and incubated for 10, 20, and 30 days to produce mycelium-based insulation boards. The process of extracting silica from wheat stalks was conducted using a 1% sodium hydroxide (NaOH) solution prior to the production of mycelium-based insulation boards. Density, water absorption, thickness swelling, modulus of rupture, modulus of elasticity, tensile strength perpendicular to the surface (Internal bonding test), and compressive strength of the mycelium insulation boards were measured. The results showed that mycelium-based insulation boards produced with GL had better physical and mechanical properties than those produced with PO. Furthermore, pretreatment of wheat straw with 1% NaOH improved the mechanical properties of the insulation boards produced. © 2024, North Carolina State University. All rights reserved
Improving the combustion process of a homogeneous charge compression ignition engine running with triple fuel blend using response surface methodology
No full textIn the present study, performance of an HCCI engine powered with ethanol/toluene/n-heptane tri-fuel blend was optimized by using response surface method. The studied independent parameters were engine speed, lambda ratio, and fuel blends. The impact of these parameters on engine torque, COVimep, CA10, CA50, indicated thermal efciency, IMEP along with emissions of NOX, CO, and HC comprehensively investigated. According to the results, the optimal HCCI engine operation condition was proposed as engine speed of 1343 rpm, lambda value of 2.29, and ethanol ratio of 22%. At this condition, the engine outputs, i.e., IMEP, COVimep, indicated thermal efciency, CA10, and CA50, engine torque were estimated to be 4.21 bar, 4.28%, 0.37, 1.41 °CA, 4.62 °CA, and 8.2 Nm, respectively. The engine-out emissions, including HC, NOX, and CO emission, were predicted to be 243 ppm, 1.05 ppm, and 0.03%, respectively. The result indicates that using ethanol/toluene/nheptane fuel mixture improved the HCCI combustion and NOX emission. The near-zero NOX emissions were recorded at all fuel mixture. However, enhancing ethanol ratio in the fuel blends showed an increase in CO and HC emissions. Overall, this study showed that response surface technique could be used as a promising method to model the HCCI engines
Alleviation of Cadmium Stress on Pollens of Quince Varieties Through Epibrassinolide
No full textEnvironmental factors significantly impact plant physiological processes, especially during pollination and fertilization. Pollen germination (PG) and pollen tube length (PTL), crucial in plant reproduction, are particularly vulnerable to environmental contaminants that affect fruit sets adversely. This study investigated the impact of varying cadmium (Cd) doses, a significant toxic heavy metal, and the alleviative potential of external 24-epibrassinolide (24-epiBL) applications on cadmium stress, determined through PG and PTL. Quince pollen viability rates, assessed using the TTC (2-3-5-triphenyl tetrazolium chloride) viability test, varied between 38.58% and 55.80%. PG and PTL rates decreased in response to higher Cd doses. The application of epiBL increased PG and PTL, but a notable decline was observed at the 2.00 μM application. A positive relationship between the application dosage of epiBL and its alleviation effect on Cd stress on PG and PTL was observed except for the 2.00 mM. Results revealed variability in PG and PTL rates among quince varieties, and PG and PTL rates decreased with higher Cd doses. This study suggests that epiBL up to 0.50 mM is an efficient tool for alleviating Cd stress in quince pollens. © Der/die Autor(en), exklusiv lizenziert an Springer-Verlag GmbH Deutschland, ein Teil von Springer Nature 2024
A Novel Cyber Security Model Using Deep Transfer Learning
No full textPreventing attackers from interrupting or totally stopping critical services in cloud systems is a vital and challenging task. Today, machine learning-based algorithms and models are widely used, especially for the intelligent detection of zero-day attacks. Recently, deep learning methods that provide automatic feature extraction are designed to detect attacks automatically. In this study, we constructed a new deep learning model based on transfer learning for detecting and protecting cloud systems from malicious attacks. The developed deep transfer learning-based IDS converts network traffic into 2D preprocessed feature maps.Then the feature maps are processed with the transferred and fine-tuned convolutional layers of the deep learning model before the dense layer for detection and classification of traffic data. The results computed using the NSL-KDD test dataset reveal that the developed models achieve 89.74% multiclass and 92.58% binary classification accuracy. We performed another evaluation using only 20% of the training dataset as test data, and 80% for training. In this case, the model achieved 99.83% and 99.85% multiclass and binary classification accuracy, respectively. © 2023, King Fahd University of Petroleum & Minerals
Optimizing foaming properties and foam mat drying process of cranberry pulp: RSM and TOPSIS approach
No full textIn this study, the impact of independent variables, including licorice root extract (LRE), xanthan gum (XG), and whipping time (WT) on foam expansion and stability of cranberry pulp foam was investigated. In this respect, the foaming properties of produced foams were optimized using Response Surface Methodology (RSM) with a Box-Behnken design (BBD). Besides, the foam produced under optimal conditions (LRE = 0.22 %, XG = 0.05 %, and WT = 7.84 min) was dried using foam mat drying (FMD) at different temperatures (50, 60, and 70 °C). According to the results, the drying characteristics were improved with increasing temperature, and in general, the powder properties were significantly affected by temperature changes. Therefore, the ideal drying temperature (70 °C) for FMD of cranberry foam was determined by the TOPSIS method. As a result, the foaming properties and the FMD process of cranberry pulp foam were successfully optimized by RSM and TOPSIS methodology, respectively. © 2024 Latin American Applied Researc
The first record of the scuttle fly, Megaselia scalaris (Loew) (Diptera: Phoridae), parasitising the citrus longhorn beetle, Anoplophora chinensis Forster (Coleoptera: Cerambycidae), from Turkiye
No full textAnoplophora chinensis Forster (Coleoptera: Cerambycidae) is a highly polyphagous and invasive species native to East Asia that makes tunnels in the stems of a variety of broad-leaved plant species and cultivated plant species, as well as citrus and hazelnut. In this study, we collected A. chinensis from hazelnut orchards in Sakarya province of Turkiye, and subsequently recovered the parasitoid Megaselia scalaris (Diptera: Phoridae) from dead adult beetles. The present study reports M. scalaris as a new natural enemy of A. chinensis, and more study is needed on this species' behaviour and biological parameters as a parasitoid
Neuroprotective Activity of Strawberry Tree (Arbutus unedo L.) Against Formaldehyde-Induced Oxidative Stress in The Rat Hippocampus
No full textFormaldehyde induces oxidative damage in hippocampal tissue and blood serum by suppressing antioxidant defenses and increasing lipid peroxidation. This results in damage to DNA, proteins, and lipids within cells, disrupting neuronal functions, and may even lead to cell death (apoptosis). Apoptosis occurs as a cellular response triggered by formaldehyde through various mechanisms, including mitochondrial dysfunction, oxidative stress, and DNA damage. Arbutus unedo L. (AUL), which is rich in antioxidants, represents a potential countermeasure. The aim of our study is to investigate the immunohistochemical and biochemical effects of AUL fruit extract (AUE) on apoptosis and oxidative stress induced by FA exposure in the rat hippocampus. The rats were divided into four groups: the experimental group (EG) received 20 mg/kg AUE by oral gavage and 10 ppm FA inhalation; the formaldehyde group (FG) received 10 ppm FA inhalation only; the sham group (SG) received 10 mg/kg AUE by oral gavage; and the control group (CG) underwent routine observation. Hippocampal tissue was isolated after blood sampling. A number of physical changes, such as yellowing of feathers and tail spots, were observed in FA-exposed groups. The biochemical analysis showed significant differences in brain-derived neurotrophic factor (BDNF), malondialdehyde (MDA), GSH (Glutathione) and nitric oxide (NO) levels between the groups. The AUE-treated groups had reduced MDA levels, suggesting a potential reduction in oxidative stress, along with lower apoptotic cell rates in caspase-3 assessments. The FG rats had lower BDNF levels than CG. The SG had the fewest apoptotic cells. All these findings indicate AUE's potential to mitigate neuron damage and reduce oxidative stress
The effects of Casimir, van der Waals and electrostatic forces on the response of nanosensor beams
No full textThe governing equations of the nanosensor beams have been modified to account for the non-local strain gradient effect, which considers the impact of material microstructure to capture the size-dependent behavior of the beams accurately. Additionally, surface and Casimir forces, which result from the interaction between the nanosensor beam and its environment, are deemed to be a precise representation of the system's performance on the nanoscale. The mechanical response of nanoscale structures is significantly influenced by intermolecular forces, which encompass van der Waals interactions and are therefore considered in the analysis. The present study employs analytical and numerical techniques to examine the interdependent influence of multiple factors on the thermal vibration and buckling behavior of magneto-electro-elastic functionally graded higher-order nanosensor beams. The investigation provides essential insights into the behavior of these very complex nanosensors in a variety of operational settings, and it also adds to the improvement of their configuration and effectiveness. The findings of this work contribute to a better knowledge of the intricate behavior of nanostructures and have relevant implications for the development of high-capacity nanosensor devices in a wide variety of sectors, such as biological sensing, environmental monitoring, and structural health monitoring devices. © 2024 Elsevier Inc
Investigation of the effect of different end anchorages against plate debonding in rc beam retrofitted with FRP plates
No full textGüçlendirilmiş polimerden yapılmış fiber kompozitler, son zamanlarda taşıyıcı yapı elemanlarının onarım/güçlendirilmesinde kullanılan diğer geleneksel malzemelere alternatif olarak popülerlik kazanmıştır. Bu kompozitler, düşük ağırlıkları, ağırlık oranına göre yüksek çekme mukavemetleri, korozyona dayanıklılıkları, yapısal elemanların onarımı ve güçlendirilmesinde uygulama kolaylığı nedeniyle dikkat çekicidir. Bilindiği gibi deney yapmak zaman alan ve maliyet gerektiren bir yöntemdir. Günümüzde gelişen bilgisayar işlem hızları sayesinde çok fazla elemandan oluşan yapılar veya yapı elemanları farklı yükleme ve sınır koşulları altında analiz edilebilmekte ve elde edilen sonuçlar bilgisayar ortamında güvenli bir şekilde grafiklenip değerlendirilebilmektedir. Bu çalışmada, ABAQUS sonlu elemanlar programı kullanılarak, eğilmeye karşı FRP plaka ile güçlendirilmiş betonarme kirişlerin uç sıyrılmasını önlemek amacıyla üç farklı polimerik fiber malzeme kullanılarak uygulanan farklı boyutlardaki ankrajların etkisi araştırılmıştır. Farklı yükseklik ve genişlik değerlerine sahip Karbon, Aramid ve Cam Fiber takviyeli polimer malzemeler ile uç ankrajı yapılan, farklı beton dayanımlarına sahip ve farklı etriye adım mesafeleri uygulanmış toplamda 279 kiriş modeli sonlu eleman yöntemi ile analiz edilmiştir. Bununla birlikte analiz sonuçlarının doğruluğu ISIS ve ACI yönetmeliklerinde benzer kirişler için önerilen analitik yöntemlerden elde edilen sonuçlarla karşılaştırılmıştır. Güçlendirme yönteminin betonarme kirişler üzerindeki etkisi birçok parametre üzerinden araştırılmıştır. Çalışmanın gerçekleştirilmesinde öncelikle literatürden elde edilen bir deneysel çalışmanın bilgisayar ortamında sonlu eleman modeli oluşturulmuştur. Doğrulaması yapılan deneysel çalışma sadece eğilme yönünden değil kesme yönünden güçlendirilmiş kirişlerin deneysel sonuçlarını da içermektedir. Bilgisayar çalışma zamanını kısaltmak ve analiz hızını arttırmak için simetri özelliğinden faydalanılarak tüm kirişlerin dörtte biri modellenmiştir. Deneysel çalışmanın sonuçları karşılaştırmalı analizlerle doğrulanmıştır. Uygulanan malzeme modelleri ile deneysel sonuçlar ve sonlu eleman model sonuçları arasında iyi bir uyum elde edilmiştir. Parametrik analiz sonuçları betonun basınç dayanımının artması, etriye aralıklarının azalması ve FRP'nin dayanımının artmasıyla yük taşıma kapasitesinin arttığını ancak U-Sargı ankrajlarının etkinliğinin azaldığını göstermiştir. Diğer taraftan yer değiştirme kapasitesinin değişimi FRP'nin dayanımındaki artışla ters orantılıdır. Ayrıca, U-Sargı ankraj genişliğini arttırmanın, yüksekliğini arttırmaktan daha etkili olduğu belirlenmiştir
Determining the attitudes of university and high school students towards sports by structural equation modelling; [Determinación de las actitudes de los estudiantes universitarios y de bachillerato hacia el deporte mediante un modelo de ecuaciones estructurales]
No full textSport is considered as an important service sector with its protective features for personal and public health, and developed countries regard sport as an indispensable part of their social life. The main purpose of this study is to assess factors affecting views of high school and university students towards sports. Within the scope of the study, the sample of the study is composed of 8546 students chosen with random method throughout Turkey. 5-point Likert scale consisting of 19 questions was used in order to determine views of the participants towards sports within the framework of the research. For analysing data, frequency analysis, reliability analysis and explanatory factor analysis were used in order to determine attitudes of students towards sports while structural equation model analyses were used in order to determine the relationship among the said factors regarding views towards sports. According to significance values of test statistics, all measured questions were statistically found significant for social- psychological attitude factor and physical mental attitude factor. According to the result of the model, there is a same-oriented and statistically significant relationship between social- psychological attitudes of students and their physical-mental attitudes. According to this result, when the views of students tend to be positive socially-psychologically towards sports, their physical-mental attitudes also become positive in parallel with this change. In line with the acquired result, it is necessary to demonstrate positive effects of sports on individuals socially, psychologically, physically and mentally in order to enable students to become more inclined to sports. © 2024, Campus EDUCA SPORTIS S.L.. All rights reserved