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Discovering the Paleolithic Ayvalık: A Strategic Crossroads in Early Human Dispersals Between Anatolia and Europe
Get PDFLocated on the northeastern Aegean coast, Ayval & imath;k was intermittently exposed as dry land during periods of lowered sea level in the Pleistocene, providing opportunities for early human occupation and mobility. This study explores the Paleolithic potential of Ayval & imath;k, a region in western Anatolia that has remained largely unexamined in Pleistocene archaeology and presents initial findings. Surveys conducted in the region identified 138 lithic artifacts at 10 sites. The most extensive assemblage, attributed to the Middle Paleolithic based on diagnostic core reduction strategies, is dominated by systematic Levallois flaking that resembles technological traits of the Mousterian tradition. In contrast, only a small number of Lower Paleolithic tools, such as handaxes and cleavers, were identified. Upper and/or Epipaleolithic traces are represented by blade and bladelet technologies. Despite preservation challenges due to Ayval & imath;k's geology and dynamic coastal processes, these findings reveal a previously undocumented Paleolithic presence and establish Ayval & imath;k as a promising locus for future research on early human dispersals in the northeastern Aegean.We extend our sincere gratitude to the Republic of Turkey's Ministry of Culture and Tourism and the General Directorate of Cultural Heritage and Museums for granting the necessary research permits. We also wish to express our appreciation to the Bal & imath;kesir Museum Directorate, Bal & imath;kesir Metropolitan Municipality, and Bal & imath;kesir City Council for their invaluable support and collaboration. Their contributions have been instrumental in the successful execution of our fieldwork. Additionally, we would like to thank all members of our research team for their dedication, hard work, and valuable contributions throughout the study. Their commitment and efforts have been essential to the success of this research. We are also grateful to the anonymous reviewers and the editorial team for their constructive feedback and guidance during the revision process, which contributed to the improvement of this article
Derin öğrenme tabanlı SNR kestirimi: Durum çalışması
Get PDFSinyal-gürültü oranı (signal to noise ratio, SNR) kestirimi, uyarlanabilir modülasyonu, etkili güç tahsisini ve güvenilir bağlantı uyarlamasını iyileştirdiği için kablosuz haberleşme sistemlerinin optimize edilmesinde önemli bir yere sahiptir. Veri yardımlı ve veri yardımsız olarak yapılan geleneksel SNR kestirim yöntemlerinin, yüksek frekans, geniş bant aralığı ve gürültüye karşı duyarlılığın fazla olması şeklinde karakterize edilen altıncı nesil (sixth generation, 6G) sistemlerinde yaşadıkları zorlukların aksine derin öğrenme (deep learning, DL) modelleri umut vaat eden bir alternatif olarak karşımıza çıkmaktadır. Bu çalışmada ResNet101V2, MobileNetV2 ve Xception olmak üzere üç adet DL modelinin SNR sınıflandırma performansı, modülasyon türlerine ait yıldız diyagramı görüntüleri yardımıyla öğrenme aktarımı tekniği kullanılarak değerlendirilmiştir. ResNet101V2, %70.8’lik bir ortalama sınıflandırma doğruluyla en üstün performansı gösterirken MobileNetV2 ve Xception sırasıyla %63.6 ve %56.8’lik doğruluk değerlerine ulaşabilmektedir. ResNet101V2, yüksek dereceli modülasyon türleri kullanılarak yapılan SNR sınıflandırmasında daha dayanıklı bir mimari olduğunu göstermiş olsa da MobileNetV2, kaynakları sınırlı senaryolar için alternatif olabilecek bir işlemsel yüke sahiptir. Tüm bunların aksine Xception, ImageNet veri setindeki görüntü sınıflandırma başarısına rağmen bu çalışmaya özgü olan SNR sınıflandırmasında aynı performansı gösterememektedir. Sonuçlar beklendiği üzere artan modülasyon derecesiyle beraber sınıflandırma doğruluğunun düştüğünü göstermektedir
Examination of sports people's opinions towards the sports sector
Get PDFSpor, hem bireyin hem toplumun gelişimi açısından önemli bir yere sahiptir. Dolayısıyla sporda önemli bir görev yürüten spor insanlarının spor sektörüne ilişkin görüşlerinin belirlenmesi, toplum üzerinde bu kadar etkiye sahip olan sporun içinde bulunduğu durumu belirlemek açısından önem arz etmektedir. Bu araştırmanın amacı spor insanlarının spor sektörüne ilişkin görüşlerini ortaya koymaktır. Araştırma betimsel bir araştırmadır. Araştırmanın amacını gerçekleştirmek için nitel araştırma yöntemlerinden olgubilim deseni kullanılmıştır. Araştırmada ölçütlü örnekleme yöntemi kullanılmış ve farklı spor dallarında en az 10 yıldır spor sektörüne hizmet eden 18 katılımcı ile yüz yüze görüşmeler yapılmıştır. Görüşmelerde araştırmacı tarafından hazırlanan açık uçlu sorulardan oluşan görüşme formu kullanılmıştır. Elde edilen veriler deşifre edilerek alanında uzman 3 kişi tarafından kodlanmıştır. Veriler içerik analiz yöntemi ile değerlendirilmiştir. Araştırma sonucunda negatif ve pozitif algı olmak üzere 2 ana tema ortaya çıkmıştır. Negatif algı ana teması altında, Yönetim ve Eğitim alt temaları ortaya çıkmıştır. Yönetim alt teması kapsamında, ekonomi, spor tesis ve malzeme, alt yapı, sistem, spor yönetimi, spor politikası, siyaset, kanun ve yönetmelikler kodları ortaya çıkarken, eğitim alt teması içinde eğitim, antrenör yetersizliği, spor kültürü ve toplumsal algı, kariyer planlaması ve gelecek kaygısı, sporda şiddet ve seyirci davranışları, sporcu kayırma, ailenin rolü ve performans kodu ortaya çıkmıştır. Pozitif algı ana tema altında toplumsal fayda, sağlık, ekonomik kazanç, genç nüfusun gelişimi, sportif başarı ve imaj, erişilebilirlik alt temaları ortaya çıkmıştır.Sports play an important role in the development of both individuals and society. Therefore, determining the views of sports professionals, who play an important role in sports, regarding the sports sector is important in order to determine the current state of sports, which has such a significant impact on society. The aim of this study is to reveal the views of sports professionals regarding the sports sector. The research is descriptive in nature. To achieve the research objective, the phenomenological research design was used. In the research, a criterion sampling method was used, and face-to-face interviews were conducted with 18 participants who had been working in the sports sector for at least 10 years in different sports disciplines. An interview form consisting of open-ended questions prepared by the researcher was used in the interviews. The data obtained were transcribed and coded by three experts in the field. The data were evaluated using content analysis. The research revealed two main themes: negative and positive perceptions. Under the main theme of negative perceptions, the sub-themes of Management and Education emerged. Within the sub-theme of Management, codes related to economy, sports facilities and equipment, infrastructure, systems, sports management, sports policy, politics, laws and regulations emerged, while within the sub-theme of Education, codes related to education, coach inadequacy, sports culture and social perception, career planning and future concerns, violence in sports and spectator behaviour, athlete favouritism, the role of the family, and performance codes emerged. Under the main theme of positive perception, the sub-themes of social benefit, health, economic gain, youth development, sporting success and image, and accessibility emerged
Developing a framework for a sustainable city index: A comprehensive approach to urban sustainability
Get PDFThis study aims to develop a Sustainable City Index to assess the sustainability performance of cities. In this context, Istanbul, with its 39 districts of diverse characteristics, has been selected as a pilot case. Although the study focuses on districts, the large population of a single Istanbul district and consistent data accessibility enhance the index's relevance at the urban scale. The study integrates environmental, social, economic, and institutional indicators to establish a comprehensive index for evaluating urban sustainability. Additionally, considering the potential impact of different levels of urbanization on sustainability performance, spatial analyses based on population density and land permeability have been conducted, and the applicability of the developed index has been examined for districts with varying degrees of urban development, including both densely built-up centers and urban peripheral areas. Furthermore, potential limitations in data accessibility have been considered, and reliable, representative indicators have been identified to assess whether it is feasible to develop a core Sustainable City Index. The findings indicate that the developed index not only provides meaningful results in measuring the sustainability performance of a city but also remains applicable to spatial contexts with differing urbanization intensities. Moreover, it demonstrates that sustainability performance can be effectively evaluated using a smaller set of representative indicators. This index serves as a valuable tool for policymakers and urban planners in developing context-specific sustainability strategies while also offering a widely applicable methodology.Scientific and Technological Research Council of Turkey [122K627]The work was supported by The Scientific and Technological Research Council of Turkey (with the number of 122K627)
Light-transmitting wood-based composite comprising microencapsulated phase-change material for sustainable energy applications in buildings.
No full textThe study explored an innovative building material that provides both lighting energy savings and thermal comfort by integrating microencapsulated phase change material (µPCM) into light-transmissive wood-based composite material. The wood-based composite comprises epoxy resin (Er), wood chips (Wc), fibre (Gf), various ?PCM concentrations, and plastic optical grids to transmit light through the plate. The highest thermal conductivity, 0.21 W/mK, was observed for µPCM0 samples. Differential scanning calorimetry (DSC) analysis presented that a composite containing 100 wt% µPCM has a melting temperature of 25 °C and a latent heat storage of 35.0 J/g. µPCM100 offered a lower surface temperature approximately 6 °C colder when the hot weather hours were taken into account. The wood composites with µPCM contributed to maintaining lower peak room temperatures and extended temperature stability overnight. While 1.923 km/s UPV was obtained in µPCM0 samples, the UPV value after 100% µPCM addition compared to the weight of the old was 1.845 km/s. Compared to the µPCM0 samples, the ErµPCMWc samples had a light transmittance rate of almost 64% greater. The study's findings could improve artificial lighting efficiency, significantly lessening indoor temperature fluctuations, enhancing thermal comfort and promoting sustainable building solutions
Numerical solutions for second-order neutral volterra integro-differential equations: Stability analysis and finite difference method
Get PDFThis work deals with the initial-value problem for a second-order neutral Volterra integrodifferential equation. First, we give the stability inequality indicating stability of the problem with respect to the right-side and initial conditions. Further, we develop a finite difference method that uses for differential part second difference derivative, for the integral part appropriate composite trapezoidal and midpoint rectangle rules followed by second-order accurate difference quantities at intermediate points. Error estimate for the approximate solution is established. In support of theoretical results, numerical results are performed by employing the proposed numerical technique
Climate-Driven Shifts in Wild Cherry (Prunus avium L.) Habitats in Türkiye: A Multi-Model Projection for Conservation Planning
Get PDFClimate change poses a serious threat to biodiversity, particularly for woody species with limited dispersal capacity such as Prunus avium L. (wild cherry). In this study, we assessed potential shifts in its suitable distribution range (SDR) across T & uuml;rkiye by applying an ensemble modeling framework that combined Generalized Additive Models (GAM), Maximum Entropy (MaxEnt), and Random Forest (RF). We used updated occurrence data (including GBIF and EUFORGEN records) and 11 ecologically relevant bioclimatic variables under SSP2-4.5 and SSP5-8.5 scenarios. Model performance was validated using AUC (Area Under the ROC Curve) and TSS (True Skill Statistic) metrics. Results suggest that while 60-70% of current SDRs remain stable by 2100, approximately 10% may be lost, with 20-23% new expansions. Temperature seasonality (Bio4) and seasonal precipitation (Bio15) were consistently identified as dominant predictors across models. Notably, newly suitable habitats are expected to be spatially isolated, limiting natural colonization. Our findings highlight the necessity of proactive conservation planning, including assisted migration and drought-resistant genotype selection, to ensure long-term persistence of wild cherry under changing climates. These results offer actionable insights for adaptive forest management and biodiversity conservation in Mediterranean-type ecosystems
Refinements of the Jensen Inequality and Estimates of the Jensen Gap Based on Interval-Valued Functions
Get PDFThe significance of the Jensen inequality stems from its impactful and compelling outcomes. As a generalization of classical convexity, it plays a key role in deriving other well-known inequalities such as Hermite-Hadamard, H & ouml;lder, Minkowski, arithmetic-geometric, and Young's inequalities. So, this inequality has become an influential concept in a wide range of scientific fields. Besides, interval analysis provides methods for managing uncertainty in data, making it possible to build mathematical and computer models of various deterministic real-world phenomena. In this paper, taking into account all of these, we first present several refinements of the Jensen inequality for the left and right convex interval-valued functions. We also provide examples with corresponding graphs to demonstrate these refinements more clearly. Next, we adopt a novel approach to derive several bounds for the Jensen gap in integral form using the gH-differentiable interval valued functions as well as various related notions. Moreover, we obtain the proposed bounds by utilizing the renowned Ostrowski inequality. The fundamental benefit of the newly discovered inequalities is that they extend to many known inequalities in the literature, as discussed in this work
Novel distance-fitness learning scheme for ameliorating metaheuristic optimization
Get PDFAn important portion of metaheuristic algorithms is guided by the fittest solution obtained so far. Searching around the fittest solution is beneficial for speeding up convergence, but it is detrimental considering local minima stagnation and premature convergence. A novel distance-fitness learning (DFL) scheme that provides better searchability and greater diversity is proposed to resolve these. The method allows search agents in the population to actively learn from the fittest solution, the worst solution, and an optimum distance-fitness (ODF) candidate. This way, it aims at approaching both the fittest solution and ODF candidate while at the same time moving away from the worst solution. The effectiveness of our proposal is evaluated by integrating it with the reptile search algorithm (RSA), which is an interesting algorithm that is simple to code but suffers from stagnating in local minima, converging too early, and a lack of sufficient global searchability. Empirical results from solving 23 standard benchmark functions, 10 Congresses on Evolutionary Computation (CEC) 2020 test functions, and 2 real-world engineering problems reveal that DFL boosts the capability of RSA significantly. Further, the comparison of DFL-RSA with popular algorithms vividly signifies the potential and superiority of the method over most of the problems in terms of solution precision.Deanship of Postgraduate Studies and Scientific Research at Majmaah University [R-2025-1669]The author extends the appreciation to the Deanship of Postgraduate Studies and Scientific Research at Majmaah University for funding this research work through the project number (R-2025-1669)
Ecotoxicological Effects of MPs as Emerging Micropollutants: Examination of Biomarkers, Current State, and Future Perspectives
Get PDFKnown ubiquitously, including in terrestrial and aquatic ecosystems, microplastics (MPs) are pollutants of concern and their harmful effects pose a growing threat. MPs, especially when considered together with increasing pollution and destructions in the ecosystem, cause deterioration of ecosystem functions and structure, raising concerns about possible negative effects on the environment. The environmental effects of microplastics, which increase especially rapidly in different environmental conditions, have been still discussed by many researchers today. While studies generally focus on the increase and effects of MPS in the oceans and seas, there is still a knowledge gap regarding its status and effects in freshwater and soil. Therefore, it is very important to evaluate the effects of MPs on both terrestrial and aquatic ecosystems. The toxic compounds used as additives in the formation of microplastics absorb the pollutants in the environment during their stay in the land and aquatic environment and then may cause the development of microorganisms in these areas or threaten the environmental media by being directly assimilated by organisms. Therefore, this situation creates an ever-increasing danger and risk potential for ecosystems, and especially their sustainable presence on land and water creates negative effects on human health and the ecosystem. So, in this context, this book section aims to define MPs pollution in terrestrial and aquatic ecosystems and to determine the ecotoxicological effects observed in ecosystems. In addition to the presence and potential effects of microplastics in soil and clean waters, their effects on human-food security, animal, ecosystem, and human health will be focused on. At the same time, biomarkers of microplastics that cause oxidative stress and damage to microalgae will be investigated. In addition, it is also aimed to present the current challenges and perspectives for future research in the context of microplastics and their effects, which are also known as worrisome. © 2025 Elsevier B.V., All rights reserved