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THz band drone communications with practical antennas: Performance under realistic mobility and misalignment scenarios
No full text<p>For 6G non-terrestrial communications, drones will offer uninterrupted connectivity for surveillance, sensing, and localization. They will also serve as drone base stations to support terrestrial base stations, providing large bandwidth, high-rate, and ultra-reliable low latency services. In this paper, for the first time in the literature, we depict the true performance of Terahertz (THz) band communications among drones by applying various channel selection and power allocation schemes with practical THz antennas within (0.75-4.4) THz under realistic mobility and misalignment scenarios. Through numerical simulations, we unveil the capacity of drone links under different channel selection and power allocation schemes within 10s to 100s of Gbps at distances (1-100) m, when drones are in motion and subject to (mis)alignment due to mobility and even under beam misalignment fading. However, when exposed to real drone mobility traces, the performance of all channel selection schemes drops significantly, sometimes by up to six orders of magnitude, due to the occasional reverse orientations of antennas. In addition to the capacity analysis, we report available frequency bands (transmission windows) considering all schemes and mobility patterns. We also identify a band that is commonly available under all considered mobility and misalignment settings, and we evaluate its performance in terms of spectral and energy efficiencies, which can be useful in designing THz transceivers for drone communications. Our findings emphasize the essence of active beam control solutions to achieve the desired capacity potential of THz drone communications, while also highlighting the challenges of utilizing the THz band for drone communications.</p>
Hydrogen evolution reaction activity of 3D-printed TiB2 and MgB2 matrix reinforced with graphene and carbon nanofiber in alkaline media
No full text<p>In the present study, the TiB2, MgB2/ Graphene (GRP)/PLA and TiB2, MgB2/Carbon Nanofiber (CNF)/PLA 3Dprinted electrodes were fabricated via the Fused Deposition Modeling (FDM) technique. The hydrogen Evolution Reaction (HER) performance of 3D electrodes was studied using electrochemical impedance spectroscopy (EIS) and cathodic polarization analysis methods in 1 M KOH media. The EIS measurement results showed that the total resistance values were significantly reduced due to the addition of GRP and CNF to TiB2/PLA and MgB2/ PLA 3D electrodes. In addition, the increase in current density with the addition of GRP and CNF to the 3D electrodes from the cathodic polarization curves supported the EIS measurement results. Moreover, a new activation method without using solvent was applied as different from the literature, to enhance the conductivity of 3D electrodes. The activation process was performed by implementing 50 cycles in 1 M KOH solution with the cyclic voltammetry method. As a result, with this study, both the synergistic effect of multiple composites and the application of the activation method have increased the HER efficiency of the 3D electrocatalyst. Thus, 3D electrocatalysts have been introduced to the energy application field.</p>
The compound effect of topography, weather, and fuel type on the spread and severity of the largest wildfire in NW of Turkey
No full text<p>The large wildfire sequence took place in July and August 2023 in & Ccedil;anakkale, recorded as the largest wildfire incident in NW, T & uuml;rkiye. The total affected area in two successive wildfires is 79.1 km2. This study presents an observation-based instance and statistical model findings of how topography as a major determinant controls wildfire propagation direction and burn severity with the contribution of weather conditions (particularly wind and temperature) and specific land use and land cover (LULC) types. The findings reveal that the & Ccedil;anakkale Strait and Biga Mountains as regional geomorphic units that extend from northeast to southwest portray the main direction of wildfire incidents guided by prevailing wind patterns and specific LULC types. The marginal section of the Biga Mountains, where the topographic relief and slope largely increase, constrain wildfire propagation, while vegetation density is higher in the steeper areas. Notably, the specific LULC which is a harvested wheat field plays an important role in determining the major direction of wildfire, primarily influenced by the prevailing northeast-to-southwest wind direction observed in the July case. Furthermore, the ordinary least square model results showed that rougher topography tends to exhibit higher burn severity which is the case for the August wildfire. The local topographic conditions (i.e., valley shape morphology) offer an appropriate observational insight for general mathematical models with the increased burn severity, and the main direction of fire and impeding areas in the August case. This study also sheds light on the significance of wind direction that can surpass the slope orientation for burn severity which is expected higher potential in equator-faced compared to the polar-faced.</p>
Recent developments and applications of artificial intelligence in solid/ liquid extraction studies
No full text<p>Artificial intelligence has great potential in extraction processes, and these technologies greatly facilitate the transformation of data into meaningful information. This review highlights inference studies using artificial intelligence and provides an overview of the types of algorithms and advanced chemometric tools used in these studies. The use of artificial intelligence, which is mostly used in classification, origin determination, and studies with large data sets, is still very limited in SPE and LPME research and investigations. This review examined SPE and LPME studies for different analytes using keywords in other algorithms under the main title of artificial intelligence.</p>
Assessing the fracture and dynamic mechanical performance of CF/PEKK joints bonded with epoxy-based adhesive film for aerospace applications: Impact of thermal and cycling hygrothermal conditions
No full text<p>This comprehensive study evaluates the performance of advanced thermoplastic composites' adhesively bonded joints (ABJs), focusing on fracture toughness and dynamic-mechanical analysis (DMA) across a wide range of environmental conditions: room temperature (RT), low temperature (LT), high temperature (HT), and cyclic hygrothermal (CHT). Fracture toughness of ABJs are assessed using double cantilever beam (DCB) and endnotched flexure (ENF) tests. Moreover, extensive efforts to bridge the gap in understanding fracture failure behavior, using acoustic emission (AE) monitoring, detailed stereo microscopy, and scanning electron microscopy (SEM), achieve a comprehensive understanding of the effects of various environmental conditions. Results indicate that HT and CHT conditions significantly reduce both mode-I and mode-II fracture toughness compared to RT, whereas LT conditions enhance mode-II toughness despite decreasing mode-I toughness. ENF and DMA results consistently demonstrate that LT-conditioned specimens exhibit the highest performance, whereas HTconditioned specimens demonstrate the lowest. The combined effects of thermal cycling and moisture in CHT conditions lead to intermediate storage modulus and a reduced glass transition temperature (Tg) of adhesive film. The novel findings exhibit the critical role of environmental factors in designing ABJs for aerospace applications, aiming to optimize performance and reliability under varying operational conditions.</p>
Deep-learning based fusion of spatial relationship classification between mandibular third molar and inferior alveolar nerve using panoramic radiograph images
No full text<p>It is crucial for clinicians to have a prior knowledge of spatial relationship between impacted mandibular third molar tooth (MM3) and inferior alveolar nerve (IAN) before an extraction procedure. This relationship may exist in four spatial forms in terms of IAN position relative to MM3 although it has not been studied extensively. To identify such relationship type, on the other hand, this study proposes a novel four-class classification framework utilizing fusion of AlexNet, VGG16, VGG19 deep learning methods using panoramic radiograph (PR) images. For this purpose, 546 PR images of impacted MM3, collected from 290 patients, were labeled by specialists using corresponding cone beam computed tomography (CBCT) images. The proposed network is trained and tested using 10 folds cross validation. Experimental studies were performed in different categories. In the first (MM3 and IAN are related/unrelated) an accuracy rate of 94.1% was obtained. In the following IAN resides on the lingual or vestibule (buccal) side of MM3 classification problem, test result of 80.6% accuracy was obtained. Finally, in the challenging four-class classification problem that includes unrelated, lingual, vestibule and other classes, an accuracy rate of 79.7% was achieved. Obtained results show that the proposed method not only presents state-of-the-art results but also suggests a new classification basis for the existing MM3-IAN relationship problem.</p>
12 Gün Savaşı'nın TASS ve IRNA Devlet Haber Ajanslarında Yansımaları
No full text<p>Bu çalışma, literatürde “12 Gün Savaşı” olarak bilinen İsrail-İran arasında yaşanan çatışmanın müttefik iki devlet olan Rusya ve İran devlet haber ajanslarında nasıl yankı uyandırdığını ortaya koymayı amaçlamıştır. 13 Haziran 2025 tarihinde İsrail Başbakanı Netanyahu, İran’ın nükleer ve askeri altyapısına karşı önleyici bir saldırı harekâtı başlatmış ve İran, “Gerçek Vaat 3” adını verdiği operasyonla bu saldırı harekâtına karşılık vermiştir. ABD ise İsrail’in yanında yer alarak İran saldırısında büyük etki yaratan bir rol üstlenmiştir. Nükleer alanda İran’ın iş birliği içinde olduğu Rusya’nın bu çatışmalara yönelik tavrı önemli bir gözle bakıldığından çalışmada Rusya ve İran devlet haber ajansları TASS ve IRNA ele alınarak bu iki ajansta çatışmalara yönelik verilen haberlerde politik anlayış incelenmiştir. Nitekim medya, küresel siyasi süreç üzerinde etkili olmakta, siyasi ve ideolojik yönelimlerini ortaya koymaktadır. Buna göre araştırmanın sorularını; "TASS ve IRNA devlet haber ajansları politika okuması yapıyor mu?" ve "Bu ajanslar hangi politik anlayış ile haber inşa etmektedirler" oluşturmaktadır. Haberler nitel bir yaklaşımla eleştirel söylem analizi tekniğiyle analiz edilmiştir. Haberlerin analizi Van Dijk’ın eleştirel söylem çözümlemesi modeli çerçevesinde gerçekleştirilmiştir. Van Dijk’ın eleştirel söylem çözümlemesi, mikro ve makro düzeylere dayanmaktadır. Mikro düzeyde; sözcük seçimleri, cümle yapıları, cümleler arasındaki nedensellik ilişkisi ve retorik incelenirken makro düzeyde; tematik ve şematik analiz uygulanmaktadır. Sonuç olarak, örneklem olarak seçilen haber ajanslarının devlet haber ajansları olması göz önüne alındığında devletlerin medyayı kendi politik düzleminde kullandığı sonucuna ulaşmak mümkün olmaktadır. Medyanın amacı, kitleyi bilgilendirmenin ötesine geçerek kitleyi manipüle etmeye dayanmaktadır. Medya, politik söylem çözümlemesi yaparak savaşa yaklaşım sergilemekte ve her ülkenin kendi politikasına yönelik haber inşa etmektedir. Bu inşayı ideoloji şemsiyesi altında yapmaktadır. Medyada verilen mesajlar kitleleri düşmana ve ötekiye karşı bütünleştirmekte ve haberlerde gerçeklik yeniden inşa edilmektedir.</p>
Does Social Exclusion Shape Impression Management? Insights from Acute and Chronic Social Exclusion Contexts
No full text<p>The experience of social exclusion can evoke a diverse array of effects. One effect of a disrupted need for belonging is that individuals may develop a mindset aimed at enhancing the likelihood of reconnecting with others. We believe that forming new social connections requires more than just impression formation; it necessitates effective impression management. This study investigated the effects of exclusion on impression management while controlling the effects of self-monitoring abilities. We conducted 4 experimental studies and a mini meta-analysis within the context of acute social exclusion and also a correlational study within the context of chronic social exclusion. Experimental studies and mini meta-analysis have shown that acute social exclusion did not affect impression management. Study 4 revealed that the experience of chronic social exclusion had negatively predicted impression management evaluations in all three dimensions (morality, sociability, competence). The findings are discussed within the framework of social exclusion, impression management tactics, and models related to loneliness.</p>
Kitap Değerlendirmesi: Tasavvufta İletişim; Anlam, Metot ve Uygulamalar Üzerine Nitel Bir Araştırma
No full text<p>Tasavvuf araştırmaları, özellikle son yıllarda sosyal bilimlerin kavramsal olanaklarını daha etkin biçimde kullanmaya başlayan disiplinlerden biri hâline gelmiştir. Mustafa Uzgur'a ait tanıtımını yaptığımız eser, bu amaçla tasavvufun klasik mirası ile psikoloji, sosyoloji ve iletişim gibi bilim dallarının kavramlarını, insanın içsel dönüşümünü bağlamında ele almaya çalışmaktadır. Mustafa Uzgur'un “Tasavvufta İletişim: Anlam, Metot ve Uygulamalar Üzerine Nitel Bir Araştırma” başlıklı çalışması, bu eğilimin ilmî açıdan değerli örnekleri arasında yer almayı hak eden, doktora tezinden kitaplaştırılmış özgün bir eserdir.1993 İstanbul doğumlu Mustafa Uzgur’un akademik yolculuğu, disiplinlerarası çalışmalara yönelen dikkat çekici bir birikimi yansıtmaktadır. Marmara Üniversitesi İlahiyat Fakültesi’nden mezun olduktan sonra yine aynı kurumda yüksek lisansını, 2024 yılında ise Ankara Üniversitesi İlahiyat Fakültesi’nde Tasavvuf anabilim dalında doktora derecesini tamamlamıştır. Çalışma, yazarın tasavvuf tarihi, iletişim teorileri ve çağdaş dinî tecrübe alanındaki birikimini aynı araştırma zemini üzerinde buluşturmaktadır. Bu yönüyle eser, çağdaş iletişim kuramlarıyla birlikte yeniden düşünme imkânı sunmaktadır ve tasavvuf araştırmalarına disiplinlerarası bir perspektif kazandırır. Çalışma, yalnızca alan araştırmacıları için değil, tasavvuf ilminin meselelerini, iletişimin psikolojik ve toplumsal boyutlarıyla ele almak isteyen tüm okuyucular için de dikkate değer bir kaynak niteliğindedir.</p>
<p><strong>Öne Çıkanlar </strong></p>
<ul>
<li>Tasavvuf, iletişim bilimi kavramlarıyla bütüncül bir şekilde analiz edilmektedir.</li>
<li>Mürşid–mürid ilişkisi, iletişimsel bir model olarak yorumlanmıştır.</li>
<li>Sözlü, sözsüz ve sembolik iletişimin tasavvufî tecrübelerdeki belirleyici rolü üzerinde durulmaktadır.</li>
<li>Makamlar, hâller, rabıta, dua ve rüya iletişim süreçleri bağlamında ele alınmaktadır.</li>
<li>Tasavvuf ilmi, modern iletişim teorileri kullanılarak disiplinler arası bir çerçevede incelenmektedir.</li>
</ul>
Fabrication of nickel oxide/copper cobaltite/graphene quantum dot conductive ink as an electrode material for selective electrochemical detection of epinephrine
No full text<p>Wearable sensors and flexible electrodes are key components of point-of-care systems, facilitating enhanced accessibility and personalization in health monitoring. These technologies permit individuals to oversee their health status and enable healthcare professionals to remotely and in real time monitor patients' health status more effectively. In this study, paper-based flexible screen-printed electrodes were constructed for the electrochemical determination of epinephrine (EP), which is crucial in the diagnosis of various diseases, with high selectivity and low detection limits. In a novel approach, nickel oxide (NiO), graphene quantum dots (GQD), and copper cobaltite (CuCo2O4) were employed in conjunctions for the first time in the development of conductive ink. The large surface area and high electrical conductivity of GQD, when combined with the electrocatalytic properties of NiO and CuCo2O4, resulted in the creation of a more efficient electroactive environment for electrochemical EP determination. The differential pulse voltammetry technique enabled the attainment of a limit of detection (LOD) of 11.66 nM within the 500-10 mu M and 2-0.02 mu M linear ranges. The reduction peak current of EP was examined throughout the analysis to eliminate the effects of possible interference species that may be present in real samples. Furthermore, the stable structures of GQDs and copper cobaltite enhanced the long-term performance of the sensors, and the combination of these materials increased the reproducibility and reliability of the sensors. Subsequently, the efficacy of the sensor was evaluated using real samples, specifically artificial sweat, and urine. The developed NiO/CuCo2O4/GQD/G/SPE sensor demonstrated satisfactory recovery values, with 94.5-110.5 %.</p>