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Enhancing petroleum logistics with innovative decision support mechanism for fuel tanker selection
Full text linkTransportation of petroleum-based products is a complex and hazardous logistics process. Selecting the appropriate transportation vehicles for this process is crucial for ensuring safety and efficiency. Therefore, prioritizing selection criteria and choosing the most suitable fuel tanker is essential in reducing potential risks and improving overall fleet operations. Given the many types of tankers available for petroleum product transportation, decision-makers should employ a multi-criteria decision-making (MCDM) approach to identify the best option for their specific needs. This study introduces a novel MCDM approach that combines the Weighted Aggregated Sum Product Assessment (WASPAS) and the Criteria Importance through Intercriteria Correlation (CRITIC) in a Fermatean fuzzy (FF) environment, addressing five main criteria and evaluating five fuel tanker alternatives. Using this approach, the research identified and prioritized key criteria for selecting an appropriate tanker model by providing insights into 24 sub-criteria. The results reveal that tanker price emerges as the most important sub-criterion, leading us to determine the M3 tanker model as the most suitable fuel tanker after carefully evaluating all 24 different sub-criteria. The findings can significantly assist petroleum firms in making informed decisions when choosing fuel tankers by considering various technical, operational, comfort, environmental, and economic factors. The results can also be used to inform policy on fuel distribution. © 2025 Elsevier B.V., All rights reserved
Some novel inequalities of Weddle's formula type for Riemann-Liouville fractional integrals with their applications to numerical integration
Full text linkIn numerical analysis, Weddle's formula is a pivotal tool for approximating definite integrals. The approximation of the definite integrals plays a significant role in numerical methods for differential equations, particularly in the finite volume method. We need to use the best approximation of the integrals to get better results. This paper thoroughly proves integral inequalities for first-time differentiable convex functions in fractional calculus. For this, first, we prove an integral identity involving Riemann-Liouville fractional integrals. Then, with the help of this identity, we prove fractional Weddle's formula-type inequalities for differentiable convex functions. Our approach involves significant functional classes, including convex, Lipschitzian and bounded functions. The primary motivation of this paper is that Weddle's formula should be employed when Simpson's 1/3 formula fails to yield the required precision. Simpson's formula is limited to third-order polynomial approximations, which may only sometimes capture the intricacies of more complex functions. On the other hand, Weddle's formula provides a higher degree of interpolation using sixth-order polynomials, offering a more refined approximation. Additionally, the paper highlights the significance of the Riemann- Liouville fractional operator in addressing problems involving non-integer-order differentiation, showcasing its critical role in enhancing classical inequalities. These new inequalities can help to find the error bounds for different numerical integration formulas in classical calculus. Moreover, we provide some applications to numerical quadrature formulas of these newly established inequalities. These approximations highlight their potential impact on computational mathematics and related fields. Furthermore, we give numerical examples, computational analysis, and graphical representations that show these newly established inequalities are numerically valid.National Natural Science Foundation of China [11971241]This work is partially supported by the National Natural Science Foundation of China (No. 11971241)
Performance analysis of node positioning strategies in cognitive wireless sensor networks based on IEEE 802.22 protocol
Full text linkBu tez çalışması, IEEE 802.22 protokolü temel alınarak geliştirilen bilişsel kablosuz algılayıcı ağ (Cognitive Wireless Sensor Network- CWSN) yapısı çerçevesinde, düğüm konumlandırma stratejilerinin ağ performansı üzerindeki etkilerini incelemektedir. Çalışma kapsamında, TV Beyaz Alanları (TV White Spaces- TVWS) üzerinde çalışan ve Kablosuz Bölgesel Alan Ağı (Wireless Regional Area Network- WRAN) altyapısını kullanan bir mimari yapılandırılmıştır. Bu yapı içerisinde, tüketici tesis ekipmanları (Customer Premises Equipment- CPE) ile baz istasyonu (Base Station- BS) arasındaki iletişim, zaman bölmeli çoklama (Time Division Multiple Access- TDMA) yöntemiyle gerçekleştirilmiştir. Her bir CPE düğümü; gecikme (delay), gecikme değişkenliği (jitter) ve veri iletim kapasitesi (throughput) gibi ağ performansını belirleyen temel metrikleri sürekli olarak ölçmekte ve bu verileri merkezi bir baz istasyonuna iletmektedir. Bu bağlamda, minimum düğüm sayısıyla maksimum kapsama alanı sağlamayı hedefleyen, sabit konum temelli bir yerleştirme stratejisi geliştirilmiş; böylece sistemin toplam kurulum ve işletim maliyetlerinin azaltılması ve operasyonel verimliliğinin artırılması amaçlanmıştır. Tasarlanan mimari ve geliştirilen algoritmalar, OPNET (güncel adıyla Riverbed Modeler) simülasyon ortamında test edilmiş; her bir CPE'ye ilişkin performans değerleri delay, jitter ve throughput parametrelerine göre zaman serileri biçiminde analiz edilmiştir. Bu veriler, ağın değişken koşullar altında sürdürülebilirliğini sağlamak amacıyla, bulanık mantık (fuzzy logic) temelli bir karar destek sistemi içinde değerlendirilmiştir. Bu sistemde, gelen veriyi sonraki hedefe yönlendiren, genellikle yönlendirme (routing) ya da kapsama genişletme işlevi üstlenen röle düğümün (relay node) seçimi için karar süreçleri yürütülmüştür. Her bir CPE'den elde edilen performans ölçümleri, bulanık mantık kuralları doğrultusunda işlenerek en uygun röle düğüm belirlenmiştir. Simülasyon sonuçları, önerilen düğüm yerleştirme yöntemi ile bulanık mantık tabanlı röle düğüm seçim algoritmasının, ağ performansında belirgin iyileşmeler sağladığını ortaya koymuştur. Daha az sayıda düğümle daha geniş bir kapsama alanı elde edilmesi, sistemin kurulum ve işletme maliyetlerini azaltmakta; bu durum, ekonomik sürdürülebilirliğin güçlendirilmesine doğrudan katkı sağlamaktadır. Elde edilen bulgular, yapay zekâ temelli karar destek sistemlerinin bilişsel ağ mimarilerinde yalnızca yüksek verimlilik değil, aynı zamanda maliyet etkinliği açısından da güçlü ve uygulanabilir çözümler sunduğunu ortaya koymaktadır.This thesis investigates the effects of node positioning strategies on network performance within the framework of a Cognitive Wireless Sensor Network (CWSN) based on the IEEE 802.22 protocol. Within the scope of the study, an architecture running on TV White Spaces (TVWS) and using Wireless Regional Area Network (WRAN) infrastructure has been configured. Within this architecture, the communication between the Customer Premises Equipment (CPE) and the Base Station (BS) is realized using Time Division Multiple Access (TDMA). Each CPE node continuously measures key network performance metrics such as delay, jitter, and throughput, and transmits this data to a centralized base station. In this context, a fixed location-based deployment strategy has been developed, aiming to provide maximum coverage with a minimum number of nodes, thus reducing the total installation and operating costs of the system and increasing its operational efficiency. The designed architecture and the developed algorithms were tested in the OPNET (now Riverbed Modeler) simulation environment, and the performance values for each CPE were analyzed in the form of time series according to delay, jitter, and throughput parameters. These data were evaluated in a fuzzy logic-based decision support system to ensure the sustainability of the network under varying conditions. In this system, decision processes were carried out for the selection of the relay node, which routes the incoming data to the next destination, usually performing a routing or coverage extension function. The performance measurements obtained from each CPE were processed according to fuzzy logic rules to determine the optimal relay node. Simulation results show that the proposed node placement method and the fuzzy logic-based relay node selection algorithm provide significant improvements to network performance. Achieving a wider coverage area with fewer nodes reduces the installation and operation costs of the system, which directly contributes to strengthening economic sustainability. The findings reveal that intelligent decision support systems offer powerful and feasible solutions in cognitive network architectures not only in terms of high efficiency but also cost-effectiveness
INVESTIGATION OF THE FLOW BEHAVIOUR OF MARTENSITIC STEELAT ELEVATED TEMPERATURES VIA UNIAxIAL TENSILE TESTS
Full text linkIn recent years, advanced high strength steels have been the main choice of automobile manufacturers due to their excellent strengths and decent formability. In this study, the forming behaviour of a martensitic steel (MART 1200) at elevated temperatures, where higher formability and an acceptable strength can be achieved, has been investigated. For this purpose, tensile test experiments have been conducted at room temperature, 175 degrees C, 275 degrees C, 375 degrees C and 475 degrees C in two different strain rates (0.005 s-1, 0.05 s-1). The flow behaviour, elongation capacity, strain rate sensitivity, strain hardening and strain hardening rate of MART1200 have been investigated and fracture surfaces and microstructures have been examined by scanning electron microscope. It has been shown that the strain rate sensitivity of MART1200 increases significantly after 275 degrees C and, for the higher strain rate, a significant improvement up to 80% in the elongation capacity has been achieved in return for a 19% strength reduction at 375 degrees C
A new specific carbon footprint (SCF) theory of serial aluminum alloys in hard turning
Full text linkPurposeThis research aims to address the critical challenge of optimizing machining processes for serial aluminum alloys, focusing on reducing carbon emissions and energy consumption while maintaining high surface quality. The study introduces the specific carbon footprint (SCF) model to evaluate CO2 emissions per unit material removed, aiming to enhance sustainable production practices in mass manufacturing.Design/methodology/approachUsing response surface methodology (RSM), experiments were conducted on 5,000, 6,000 and 7,000 series aluminum alloys to assess the impact of cutting speed and feed rate on surface quality, energy consumption and carbon footprint. Energy usage data were collected, and analysis of variance was used to identify the contributions of process parameters.FindingsThe results revealed that feed rate is the most influential factor, contributing 51.8% to the SCF, followed by cutting speed at 32%. Optimal conditions reduced CO2 emissions by 37%, cutting the carbon footprint from 516.4 tons to 325 tons annually. Among the materials tested, the 6,000 series exhibited the best machinability, balancing low energy consumption and high surface quality.Research limitations/implicationsThe proposed SCF model serves as a novel metric for sustainable manufacturing, enabling precise evaluation of carbon emissions in machining processes. This work establishes a benchmark for optimizing machining parameters, significantly reducing environmental impact in mass production scenarios.Originality/valueThis study pioneers the integration of SCF into machining optimization and offers actionable insights for sustainable manufacturing. It highlights the potential of using RSM to simultaneously optimize energy efficiency, surface quality and carbon emissions, providing a valuable framework for future research and industrial applications
Generalized Padovan Pauli Quaternions
Full text linkThe main purpose of this study is to construct a new type special number system which is defined as generalized Padovan Pauli quaternion with non-negative and negative subscripts. Furthermore, we give some special cases with respect to the initial values and examine them, as well. We obtain not only new equations but also recurrence relations, Binet formulas, generating functions, exponential generating functions, summation formulas, and special determinant equalities with a numerical example regarding this new number system. After all, we construct algorithms for calculating the generalized Padovan Pauli quaternions with non-negative and negative subscripts. Then, we present the R-linear transformation of this new type special Pauli quaternions. © 2025 Elsevier B.V., All rights reserved
A Comparative Study on Friction Performance and Mechanical Properties of Printed PETG Materials With Different Patterns
Full text linkInvestigating the mechanical and wear properties of widely used PETG (polyethylene terephthalate glycol) filaments is important to understanding the material's performance, reliability, and suitability in different application areas. This study performed tensile and wear tests on PETG samples produced with a 3D printer using four infill patterns (honeycomb, grid, triangular, and gyroid). The study aimed to investigate the effect of infill patterns on the tensile and wear properties of the samples. In the evaluations, friction coefficient, wear rate, SEM microscope images, hardness test, temperature measurement during tensile, diameter accuracy value, Young's modulus, and yield values were analyzed. The mechanical results present that the triangular pattern showed 133% higher mechanical strength compared to other patterns with the highest Young's modulus. As a result of the wear tests, horizontal patterns showed more homogeneous wear, while vertical patterns caused irregular wear by creating more brittle structures. It was found that dense patterns, such as honeycomb and grid, were more resistant to wear. The triangular pattern samples can be preferred for high strength and thermal stability, while gyroid and grid pattern samples can be used in the flexibility field. The results revealed that different infill patterns significantly affect the mechanical and tribological performances of the materials and that appropriate pattern selection can optimize performance in engineering applications
Determination the natural plant compositions and species distribution model in different habitat types of Duzce (Turkiye)
Full text linkBackground: Turkiye is a very rich country in terms of the distribution and diversity of plants. Despite these current conditions, natural plant species are not sufficiently used in designing urban landscapes. The research aims to reveal an ecological model approach to urban planting by determining the ecological indicator values (EIV's) and coexistence in nature of the species detected in the natural vegetation, revealing the potential of plants to come together. Results: Within the scope of research, natural areas in Duzce Plain and at the points touching the plain were determined according to the CORINE land cover classification, and 5 different habitat types were determined as forest habitat, riparian areas, rocky habitat, wetlands and meadow habitat. In this study, 420 plant taxa belonging to 89 families which were taken from 33 points and 168 sample areas, were identified. Both natural plant species determined by collecting plant species from the area and plant species diversity will be revealed by determining the ecological demands of the plants. After determining whether the coexistence of plant species collected and identified in these habitat types is distributed in an interdependent manner, scenarios regarding the coexistence of plants were constructed with the help of the latent variables model (LVM's) by R software program. Conclusion: Some of the plant species with the highest percentage of presence according to the plant layers were selected, and plant compositions with high coexistence were proposed according to the LVM's
Effect of different work-to-rest ratios on physiological and perceptual responses to kickboxing specific high intensity intermittent exercise in elite male kickboxers
Full text linkThis study examined how different rest periods during high-intensity, intermittent kickboxing exercise affect physiological and perceptual responses in nine elite kickboxers. After being informed about the nature of the study, the athletes performed three exercise sessions consisting of kicks and punches with 1:1, 1:2 and 1:3 work-to-rest ratios in a randomised order, with 48 hours between each session. Their heart rate (HR) was measured at rest, immediately after, and six minutes after each exercise protocol. The athletes performed a countermovement jump (CMJ) test before and after exercise. Rating of perceived exertion (RPE) and muscle soreness (PMS) were measured immediately after exercise. The number of kicks and punches performed by the athletes was recorded. Different rest ratios did not affect heart rate (F2, 14 = 1.08, p = 0.36). There was no difference in the number of kicks or punches performed by the athletes among different rest intervals (F2, 16 = 1.59, p = 0.24; F2, 16 = 1.70, p = 0.21). Exercises with different rest periods did not induce changes in CMJ (F2,16 = 0.69, p = 0.52). While the PMS responses of the athletes did not differ among the different rest intervals (F2,16 = 1.27, p = 0.31), the RPE values did differ among the exercises with the different rest intervals (F2, 16 = 3.70, p = 0.04). The athletes presented higher RPE values with the 1:1 interval than with the 1:2 and 1:3 intervals (p < 0.05). Kickboxing-specific HIIE with different rest intervals did not induce any physiological or performance differences, but led to a higher RPE following a short rest interval than a long one. These findings highlight that perceived difficulty (i.e. RPE) increases as the rest period shortens. Thus, there is a need to optimise HIIE protocols for targeted results and subjective recovery needs in this sport
Phubbing ve yakın ilişkilerde yalnızlık arasındaki ilişkide sosyal bağlılığın aracı rolü
Full text linkBu çalışma, phubbing davranışının bireylerin sosyal bağlılık düzeyi ve yakın ilişkilerde deneyimledikleri yalnızlık üzerindeki etkisini incelemeyi amaçlamaktadır. Mobil teknolojilerin sosyal ilişkiler üzerindeki artan etkisi, phubbing, sosyal bağlılık ve yakın ilişkilerde yalnızlık arasındaki dinamikleri ele almayı araştırma açısından önemli kılmaktadır. Araştırmada, sosyal bağlılığın phubbing ile yakın ilişkilerde yalnızlık arasındaki ilişkide aracı rol oynayıp oynamadığı değerlendirilmiştir. Türkiye genelinde 18–48 yaş aralığında yer alan 406 katılımcıdan (218 kadın, 188 erkek) elde edilen veriler çevrimiçi anket yoluyla toplanmış ve SPSS 26.0 programı aracılığıyla analiz edilmiştir. Analiz sürecinde Bağımsız Örneklemler t-Testi, Tek Yönlü Varyans Analizi (ANOVA), Pearson Korelasyon Analizi ve Hiyerarşik Regresyon Analizi uygulanmıştır. Bulgular, sosyal bağlılık, phubbing ve yakın ilişkilerde yalnızlık değişkenlerinin bazı demografik değişkenlere göre anlamlı farklılıklar gösterdiğini ortaya koymuştur. Regresyon analizine göre, sosyal bağlılık hem phubbing hem de yakın ilişkilerde yalnızlık üzerinde negatif yönde; phubbing ise yalnızlık üzerinde pozitif yönde anlamlı bir yordayıcıdır. Ayrıca, sosyal bağlılığın phubbing ile yakın ilişkilerde yalnızlık arasındaki ilişkide kısmi aracı bir rol üstlendiği belirlenmiştir