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Unveiling the power of features: A comparative study of machine learning and deep learning for modulation recognition
Full text linkWireless communication systems rely on amplitude, frequency, and phase parameters for signal transmission. Traditional modulation recognition (MR) techniques, employing likelihood-based (LB) and feature-based (FB) methods, struggle with accurate classification, particularly at low signal-to-noise ratios (SNR) and increasing modulation complexity. Machine learning (ML) and deep learning (DL) algorithms, which efficiently utilize in-phase/quadrature (IQ) and r-radius/θ-angle (rθ) data representations to enhance MR performance. DL, utilizing artificial neural networks (ANN), minimizes the need for extensive feature engineering, making it adept at handling diverse modulation types and challenging SNR conditions. This study systematically examines dataset generation parameters to reveal their impact on MR performance. By focusing on these underlying parameters, the analysis provides deeper insights into how data characteristics influence model performance, offering a foundational understanding for optimizing dataset configurations in MR tasks. Evaluating ML and DL models across datasets, results show DL model consistently outperforms ML models, achieving up to 79.41 % accuracy on IQ-based datasets. DL's hierarchical feature extraction enhances adaptability, particularly with larger datasets, reduced window lengths (WL), and specific θ ranges (e.g., radians or smaller degree intervals). For ML models, datasets based on IQ, rθ, and IQrθ parameters yield better results but remain below 70 % accuracy. Overall, DL model exhibits robust adaptability to complex signal environments, highlighting their effectiveness in advancing modulation recognition for next-generation wireless communication systems. © 2025 Elsevier B.V., All rights reserved
Space Adventure for Little Explorers: Implementing the Engineering and Entrepreneurship Design Process in Preschool Education
Full text linkThis study aimed to design, implement, and evaluate the feasibility of an activity titled \"Space Adventure for Little Explorers\", integrating the engineering and entrepreneurship design model within the STEM education framework into preschool education. The activity was structured in four stages: (1) Discovery with the Family, (2) Sharing My Discoveries, (3) Engineering and Entrepreneurship Design Process, and (4) Design Evaluation. The study was conducted with 20 kindergarten students (11 girls, 9 boys) aged five, attending a public primary school during the 2023–2024 academic year. Students with special needs were excluded. The \"I Design My Own Rocket\" activity was implemented over three days. A qualitative case study approach was employed, gathering data from preschool teachers, students, and their families. Findings indicated that considering students' readiness levels and employing various teaching techniques during phase transitions enhanced the activity’s effectiveness. The integration of abstract concepts with real-life experiences facilitated students’ conceptual understanding. Additionally, family-school collaboration and peer learning contributed significantly to the learning process. The activity provided students with hands-on experiences in problem-solving and engineering concepts, fostering creativity and engagement. It also improved their cooperation and communication skills. Students found the activity enjoyable and expressed a desire to participate again. Family involvement played a crucial role in enhancing learning motivation and self-confidence. It also supported students in developing information-seeking skills, reinforcing peer learning, and enriching the overall learning experience. In conclusion, integrating the engineering and entrepreneurship design model into preschool STEM education was found to be a feasible and effective approach. The structured design of the activity, combined with family engagement and peer collaboration, contributed to students' active participation and meaningful learning experiences
An analysis of the activities of the Union of Turkish World Municipalities from the perspective of sustainable development1
Full text linkGlobal problems such as global warming, climate change, desertification, biodiversity loss, deforestation have caused many natural and biological disasters. Disasters threaten sustainable development by shrinking living spaces. The solution of global problems is expected to be supported by international principles and policies that countries and urban governments will develop. For this reason, in 2015, the United Nations published the document Agenda 2030: Sustainable Development Goals (SDGs). The document includes 17 goals, 169 targets. In many ways, the objectives are within the scope of duties and responsibilities of local governments, especially municipalities. In this study, the Union of Turkish World Municipalities (TDBB) was chosen as an example. The aim of the study is to examine whether the activities of the association are compatible with the SDGs. Using a qualitative research method, the activity reports of the TDBB between 2016-2022 were analyzed through content analysis. The union's activity headings were grouped to determine whether they fall under the SDGs, and the alignment of the activities with the goals and the level at which they correspond were identified. The findings were presented using conceptual mapping techniques. It is believed that the results of the study will guide the planning of the union's future activities
Diagnosis of Lichen Sclerosus, Morphea, and Vasculitis Using Deep Learning Techniques on Histopathological Skin Images
Full text linkSkin diseases are very common all over the world. The examination can be done by photographing the relevant area or taking a tissue sample to diagnose skin diseases. Examining tissue samples allows examination at the cellular level. This study discussed three skin diseases: lichen sclerosus, morphea, and cutaneous small vessel vasculitis (vasculitis). For this problem, which does not have an open-access dataset in the literature, a dataset consisting of histopathological images belonging to each class was created. Convolutional neural network models were created for this three-class classification problem, and their results were evaluated. In addition, in this problem where it is difficult to obtain sample images, the efficiency of transfer learning methods was evaluated with a limited number of examples. For this purpose, tests were performed with VGG16, ResNet50, InceptionV3, and EfficientNetB4 models, and the results were given. Among all the results, the accuracy value of the VGG16 model was 0.9755 and gave the best result. However, although the accuracy value was quite good, precision, recall, and f1-score metrics values were around 0.65. This shows deficiencies in how often the model correctly predicts the positive class and how well it predicts all positive examples in the dataset. © 2025 Elsevier B.V., All rights reserved
Zilzâl Sûresinin Yedi ve Sekizinci Âyetlerinin Anlamı Üzerinde Bir Değerlendirme
Full text linkYüce Allah, hayır ve şerri işleyebilecek yetenekte yarattığı insana akıl vermek, peygam-ber göndermek ve kitap indirmek suretiyle rehberlik etmiş, iman edip etmemeyi, iyi ve kötü işleri yapıp yapmayı iradesine bırakmıştır. Bununla birlikte ahirette cehennem olduğunu bildi-rerek insanları inkâr ve isyandan sakındırmıştır. Cennet vaat etmek suretiyle iman, itaat ve iba-detlere teşvik etmiş, insanın dünyada küçük veya büyük, az veya çok yaptığı iyi veya kötü işlerinin kaybolmayacağını ve ahirette bunun hesabının verileceğini bildirmiştir. Bu âyetlerden biri de Zilzâl sûresinin yedi ve sekizinci âyetleridir: “Kim zerre ağırlığınca bir hayır ve salih amel işlerse onu görür. Kim de zerre ağırlığınca bir kötülük ve günah işlerse onu da görür.” Âyette geçen “kimse”, mümin mi kâfir mi? Her ikisi mi? “Zerre” kadar iyi işin mükâfatı, “zerre” kadar kötü işin cezası dünyada mı ahirette mi olacak? Ahirette ise kâfir zerre kadar iyi işin mükâfatını, mümin zerre kadar kötü işin cezasını görecek mi? Bütün bunlar âyette açık değildir. Bu sebeple sahabe döneminden itibaren müfessirler âyeti anlamada ittifak edememiş-lerdir. Makalemizde âyetteki “amel, hayır ve şer” kavramları, “kimse” ismi ve “onu görür” cümlesi ile ne kast edildiği, bunun dünyada mı ahirette mi olduğu hususları ele alınmıştır
Language needs analysis on teaching Turkish as a foreign language
Full text linkYabancılara Türkçe öğretimi üzerine yapılan bu çalışma, üniversitelerin bünyesinde bulunan Türkçe dil eğitim uygulama ve araştırma merkezlerinde (TÖMER) öğrenim gören farklı ulus ve kültürlere mensup öğrencilerin Türkçe öğrenme ihtiyaçlarını belirlemeyi ve tespit edilen bu ihtiyaçlara yönelik öneriler sunmayı amaçlamaktadır. İstanbul, Sakarya ve Düzce illerinde yer alan dört farklı üniversiteden TÖMER'de eğitim gören toplam 505 öğrenciye ulaşılmıştır. Araştırmada, ihtiyaç analizi için karma yöntem uygulanmış; Türkçe Dil İhtiyaçları Ölçeği ve yarı yapılandırılmış görüşme formu ile veri toplanmıştır. Verilerin analizleri Türkçe dil öğreniminde dil öğrenme amaçları Ticaret Yapma, Eğitim ve İş Olanakları, Bireysel İlgi ve İhtiyaçlar ve Sınıf İçi İletişim boyutlarında incelenmiş; demografik yapıya göre boyutların değişkenliği araştırılmıştır. Cinsiyet değişkenine göre anlamlı bir fark gözlemlenmemiştir; ancak devam edilen Türkçe kur ve Türkçe öğrenme süresi değişkenlerine göre özellikle A1-A2 düzeyindeki öğrencilerin daha yüksek ihtiyaçlara sahip olduğu saptanmıştır. Görüşme formundan elde edilen analizler sonucunda öğrencilerin Türkçe öğrenme amaçlarının; eğitim, mesleki hedefler, günlük yaşam, kalıcı yaşam planları ve bireysel ilgi gibi temalar etrafında şekillendiği belirlenmiştir. Ayrıca derste kullanılan etkinliklerin yeterliliğine ilişkin görüşler, olumlu, olumsuz ve koşullu olumlu biçiminde sınıflandırılmış; öğretmen desteği, materyal çeşitliliği ve seviye uyumu gibi unsurlar ön plana çıkmıştır. Sözlü etkinliklere yönelik değerlendirmelerde ise sözlü iletişim becerilerini geliştirme, anlamayı kolaylaştırma ve pratik yapma fırsatı gibi kazanımlar öne çıkarken; akademik dil yetersizliği, içerik uyumsuzluğu ve kaygı gibi sınırlayıcı faktörler de tespit edilmiştir Bununla birlikte öğrencilerin derste teknolojik, görsel-işitsel ve etkileşimli materyallere önem verdikleri görülmüştür. Öğretmen tutumlarının değerlendirilmesinde iletişime açık, motive edici ve öğrenci merkezli bir yaklaşım beklentisinin yüksek olduğu tespit edilmiştir. Araştırmanın sonuçları, Türkçe öğretiminde kullanılan mevcut materyal ve yöntemlerin öğrencilerin ihtiyaçlarını karşılamada yetersiz olduğunu göstermiştir. Araştırmada elde edilen sonuçlar TÖMER'lerde eğitim alan öğrencilerin dil ihtiyaçlarını ortaya koymuştur. Dil öğretiminde öğrenci merkezli yaklaşımların benimsenmesi, materyallerin çeşitlendirilmesi, teknoloji entegrasyonunun güçlendirilmesi ve öğretmenlerin pedagojik olarak desteklenmesi önerilmiştir.This study on teaching Turkish as a foreign language aims to identify the Turkish language learning needs of students from diverse national and cultural backgrounds who are studying at Turkish Language Education, Practice and Research Centers (TÖMER) affiliated with universities. A total of 505 students enrolled in TÖMER centers at four different universities located in Istanbul, Sakarya and Düzce were included in the study. A mixed-methods approach was employed for the needs analysis, and data were collected using the Turkish Language Needs Scale and a semi-structured interview form. The data were analyzed in terms of the following dimensions: Purposes of Language Learning in Turkish, Trade, Educational and Career Opportunities, Individual Interests and Needs, and In-Class Communication. In addition, the variation in needs across demographic variables was examined. No statistically significant difference was found with regard to gender; however, students at the A1–A2 level were found to have higher needs compared to those at more advanced levels in terms of both language level and duration of learning. The qualitative data analysis revealed that students' purposes for learning Turkish revolve around themes such as education, career goals, daily life, permanent residence plans, and personal interests. Views on the adequacy of classroom activities were categorized as positive, negative, and conditionally positive; key elements highlighted by students included teacher support, material diversity, and content-level alignment. Evaluations regarding oral activities emphasized benefits such as improving oral communication skills, facilitating comprehension, and providing practice opportunities, while some limitations were noted, including inadequate academic language, content-level mismatches, and anxiety. Furthermore, students expressed a strong preference for technological, audiovisual, and interactive materials in the classroom. In terms of teacher attitudes, students reported high expectations for communicative, motivating, and student-centered approaches. The findings of the study indicate that the current materials and methods used in teaching Turkish may fall short in meeting students' diverse learning needs. Based on the results, it is recommended that language instruction in TÖMER centers adopt more student-centered approaches, diversify instructional materials, strengthen technology integration, and provide pedagogical support to instructors
Censorship and self-censorship in turkish cinema after 2000
Full text linkÖZET Türk sinemasında, sansür ve otosansür, sektörün ilk günlerinden itibaren önemli bir sorun olmuştur. Özellikle 2000 sonrası dönemde, Türkiye'deki sanat ortamında filmlerin içeriğini kontrol etme ve ifade özgürlüğünü sınırlandırma çabaları artmıştır. Bu süreçte, film yapımcıları ve sanatçılar, toplumsal ve siyasi baskılarla karşılaşmamak için sıklıkla otosansür uygulamaktadır. Bu tez, sansür ve otosansürün Türk sinemasındaki etkilerini incelemeyi ve film yapımcılarının bu karmaşık ortamda karşılaştıkları zorlukları ortaya koymayı amaçlamaktadır. 2000 sonrası dönemdeki toplumsal, politik ve kültürel değişimlerin sinemaya yansımalarını analiz ederek, sansür ve otosansürün sinemasal üretim süreçleri üzerindeki etkisini detaylandıracaktır. Çalışma, sansür ve otosansürün yalnızca bir kontrol aracı olmanın ötesinde, sanatçıların yaratıcı ifade biçimlerini ve toplumsal eleştirilerini nasıl şekillendirdiğini ortaya koymayı hedeflemektedir. Ayrıca, bu olguların Türk sinemasının estetik ve içeriksel evrimindeki rolü, sinema sanatının toplumsal değerler, devlet politikaları ve kültürel normlarla ilişkisi üzerinden irdelenecektir. Çalışmanın diğer bir amacı, 2000 sonrası dönemdeki sansür ve otosansür anlayışlarının, Türkiye sinemasında yeni anlatı biçimlerinin ve söylemsel stratejilerin gelişimine nasıl katkıda bulunduğunu tartışmaktır. Sonuç olarak, Türk sinemasında sansür ve otosansürün azaltılması, sanatın özgür gelişimini sağlayarak sinema sektörünü uluslararası düzeyde daha rekabetçi bir hale getirebilir. Bu süreçte yapılacak düzenlemeler ve toplumsal farkındalık çalışmaları, Türkiye sinemasının sanatsal çeşitliliğini artırarak daha özgür bir yaratım ortamının oluşmasına katkı sağlayacaktır.ABSTRACT In Turkish cinema, censorship and self-censorship have been a significant problem since the early days of the sector. Especially in the post-2000 period, efforts to control the content of films and limit freedom of expression have increased in the art environment in Turkey. During this period, filmmakers and artists frequently practice self-censorship in order not to face social and political pressures. This thesis aims to examine the effects of censorship and self-censorship on Turkish cinema and to reveal the difficulties filmmakers face in this complex environment. By analyzing the reflections of social, political and cultural changes in the post-2000 period on cinema, it will detail the effects of censorship and self-censorship on cinematic production processes. The study aims to reveal how censorship and self-censorship, beyond being merely a means of control, shape artists' creative forms of expression and social criticism. In addition, the role of these phenomena in the aesthetic and content evolution of Turkish cinema will be examined through the relationship of cinema art with social values, state policies and cultural norms. Another aim of the study is to discuss how the concepts of censorship and self-censorship in the post-2000 period contributed to the development of new narrative forms and discursive strategies in Turkish cinema. As a result, reducing censorship and self-censorship in Turkish cinema can make the cinema sector more competitive at the international level by ensuring the free development of art. The regulations and social awareness studies to be made in this process will contribute to the formation of a freer creative environment by increasing the artistic diversity of Turkish cinema
Somatic drought stress memory affects leaf morpho-physiological traits of plants via epigenetic mechanisms and phytohormonal signalling
Full text linkDrought stress memory in plants is an adaptive mechanism that enhances resilience to future water stress through physiological and molecular modifications triggered by previous drought events. This review explores somatic drought stress memory within a plant's lifespan, with a specific focus on leaf and stomatal morphology, minimum leaf conductance, photosynthetic efficiency, water-use efficiency, antioxidant capacity, and leaf senescence. We examine how epigenetic mechanisms-such as DNA methylation, histone modifications, and non-coding RNAs-regulate gene expression in coordination with hormonal signalling pathways. Phytohormones, including abscisic acid, jasmonic acid, ethylene, salicylic acid, auxins and cytokinins, are central to these processes, influencing key morphological and physiological adaptations, such as stomatal regulation, cuticle thickness, water retention, and improved water-use efficiency. The review synthesizes current knowledge on the molecular and hormonal networks underlying these adaptations and their impact on leaf architecture and metabolism. Despite advancements, critical gaps remain in identifying the specific genes and pathways involved, understanding the longevity of epigenetic marks, and elucidating the intricate cross-talk between phytohormones during drought stress memory. This review emphasizes the need for integrated-omics approaches to map epigenetic modifications and uncover their roles in developing drought-resistant plants through targeted stress priming strategies.Helmholtz Initiative and Networking fund [W2/W3-156]FA acknowledges funding by the Helmholtz Initiative and Networking fund (W2/W3-156)
Optimizing Prostate Cancer Diagnosis: A Prospective, Randomized Comparison of 12-core vs. 20-core Biopsy for Detection Accuracy and Upgrading Risk
No full textObjective: This study compares the diagnostic efficacy of 12-core and 20-core transrectal ultrasound (TRUS)-guided prostate biopsy protocols in detecting prostate cancer (PCa) and evaluates the clinical significance of extended biopsy protocols. Materials and Methods: A prospective, randomized, single-center study was conducted with 511 patients who underwent TRUS-guided prostate biopsy for suspected PCa. Patients were randomly assigned to either a 12-core biopsy group (n=248) or a 20-core biopsy group (n=263). The primary endpoint was the cancer detection rate, while secondary endpoints included clinically significant cancer detection [International Association of Urological Pathology (ISUP) grade >= 2], biopsy-pathology correlation, upgrade rates, and complication assessment. Results: The 20-core biopsy group had a significantly higher cancer detection rate (39.2%) compared to the 12-core group (28.6%). However, clinically significant cancer detection rates were similar between the groups. The 20-core protocol reduced the likelihood of ISUP grade 1 cancer being upgraded after radical prostatectomy, improving diagnostic accuracy. A strong correlation was observed between tumor burden in biopsy and radical prostatectomy specimens. Prostate-specific antigen density analysis identified an optimal cutoff value of 0.1058, providing 66.1% diagnostic accuracy. Complication rates were comparable between the protocols [5.65% (n=14), 6.46% (n=17)]. Conclusion: The 20-core biopsy protocol enhances overall cancer detection and reduces unnecessary upgrading in low-risk PCa cases, improving diagnostic precision. While multiparametric magnetic resonance imaging (MRI)-guided fusion biopsy offers high accuracy, its limited availability makes extended biopsy protocols a viable alternative, particularly in centers without MRI-based targeting methods. Further multicenter studies are needed to refine biopsy strategies for clinical practice
Enhancing Cognitive Radio Sensor Network Security with Smart Contract for Field Hospitals
Full text linkIn this paper, a cognitive radio medical sensor network based on smart contract is proposed for secure communication in field hospitals. Field hospitals usually utilize cognitive radio based opportunistic networks for health data transmissions due to extraordinary sudden occasions. And, cognitive radio based opportunistic networks is prone to risks. So, security is a crucial factor for opportunistic networks in cognitive process such as spectrum sensing [1]. Secure data transmission is very important for patient related sensed data in field hospitals. Failure to transmit, or incorrect transmission of values such as vitamin levels, glucose levels in the blood can critically impact the treatment applied to the patient [2]. In our network structure, sensor nodes use the carrier sense multiple access (CSMA) technique for medical communication. Utilizing our smart contract based approach, security measures were taken in the field hospital environment. Since secure communication is crucial in field hospitals, a smart contract-based data sensing approach is proposed to enhance network security. Sensor nodes are placed to cover the whole region to sense parameters. The values sensed by the sensor nodes were composed by the base station. The simulation model of our proposed approach was implemented using Riverbed Modeler software. Owing to our proposed smart contract based approach for cognitive medical sensor networks, the field hospital environment was supervised securely with wireless sensor nodes. © 2025 Elsevier B.V., All rights reserved