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Yüksek Başarımlı ve Kaynak Verimli Düşük Yoğunluklu Eşlik Denetim Kodu Çözücü Tasarımı
No full textIsik UniversityLow Density Parity Check (LDPC) codes have gained popularity in communication systems due to their capacity-approaching error correction performance. In this study, a high-performance LDPC decoding algorithm with extremely low resource usage is proposed. Among the hard decision class of LDPC decoders, Gallager B (GaB) provides high-performance hardware due to its computational simplicity. However, GaB suffers from poor error-correction performance. In this study, a new intrinsic computation technique for GaB called Intrinsic Gallager B (IGaB) is introduced to improve error correction performance. Our simulation results show that the IGaB algorithm provides better error correction performance compared with GaB. GaB and IGaB algorithms are implemented on Field Programmable Gate Array (FPGA) to compare hardware performance. © 2025 Elsevier B.V., All rights reserved
Context-Aware Beam Selection for IRS-Assisted Mmwave V2I Communications
No full textKose, Abdulkadir/0000-0002-6877-1392;Millimeter wave (mmWave) technology, with its ultra-high bandwidth and low latency, holds significant promise for vehicle-to-everything (V2X) communications. However, it faces challenges such as high propagation losses and limited coverage in dense urban vehicular environments. Intelligent Reflecting Surfaces (IRSs) help address these issues by enhancing mmWave signal paths around obstacles, thereby maintaining reliable communication. This paper introduces a novel Contextual Multi-Armed Bandit (C-MAB) algorithm designed to dynamically adapt beam and IRS selections based on real-time environmental context. Simulation results demonstrate that the proposed C-MAB approach significantly improves link stability, doubling average beam sojourn times compared to traditional SNR-based strategies and standard MAB methods, and achieving gains of up to four times the performance in scenarios with IRS assistance. This approach enables optimized resource allocation and significantly improves coverage, data rate, and resource utilization compared to conventional methods
Looking for Stability in Chaos: A Scoping Review of Relational Turbulence Theory from a Dyadic Perspective
No full textThe current scoping review overviews articles that apply the relational turbulence model/theory to guide the implementation of actor-partner interdependence modeling within a structural equation modeling framework. Sixteen studies are examined in the final synthesis of the review. Research themes center on communication strategies and social connection, dispositional and situational factors, and, lastly, mental and physical health. Current work illustrates that scholars are primarily interested in sources of relational uncertainty and its intrapersonal and interpersonal consequences. Sources of partner influence and their implications for relational dynamics are also examined across the synthesized studies. Overall, more actor effects than partner effects were statistically significant. Commercial statistical programs appear preferred for analyzing dyadic data, and assessments of fit indices are reported to evaluate proposed analytic models in this body of research. Methodological and theoretical limitations are highlighted, and implications for future research are discussed
Comparative Analysis of Hybrid Geothermal-Solar Systems and Solar PV With Battery Storage: Site Suitability, Emissions, and Economic Performance
No full textDincer, Ali Ersin/0000-0002-4662-894X;Renewable energy integration has become a critical focus in the global effort to reduce carbon emissions and diversify energy sources. In regions with distinct geographic features, such as Turkiye, combining different renewable technologies can offer enhanced energy security. This study investigates the site suitability and economic and environmental performance of hybrid geothermal-solar systems and solar PV systems with battery storage across the provinces of Osmaniye, Hatay, and Kilis, of Turkiye. Using the fuzzy-AHP method, site suitability is evaluated, addressing a key gap in comparing these systems' adaptability to varying geographic conditions. This study is the first to directly compare these two renewable energy technologies in terms of site suitability. The findings reveal significant differences in site suitability, with solar PV systems with battery storage demonstrating broader applicability across the region. The suitable sites (20-100 % suitability) cover 1260.82 km(2) for solar PV systems with battery storage and only 122.18 km(2) for hybrid geothermal-solar systems. In terms of environmental impact, hybrid geothermal-solar systems exhibit significantly lower carbon emissions, averaging 44.6 kg CO2/MWh, compared to 123.8 kg CO2/MWh for solar PV systems with battery storage. Economically, hybrid geothermal-solar systems also outperform with a lower levelized cost of electricity of 0.254 kWh for solar PV systems. These results highlight the environmental and economic advantages of hybrid geothermal-solar systems, while also emphasizing their limited scalability to regions with geothermal activity. Conversely, solar PV systems, despite their higher emissions and costs, offer greater flexibility and potential for widespread deployment
Crashworthiness Evaluation of 3D-Printed Hybrid-Design Multi-Cell Energy Absorbers Under Lateral Compression for Unmanned Aerial Vehicles
No full textEnergy absorbers can be strategically integrated into critical areas of unmanned aerial vehicles to protect their structural integrity and electronic components in the event of an accident. In this study, hybrid-design multi-cell energy absorber configurations were proposed, and their crashworthiness performance and collapse mechanisms were comparatively analyzed. Hybrid energy absorbers were designed considering circular, square, hexagonal, and re-entrant unit cell geometries. The energy absorber configurations were produced via additive manufacturing. Compared to the single-cell circular energy absorber, the hybrid-design multi-cell approach resulted in a higher peak crushing force value, while offering considerable enhancements in other crashworthiness parameters. Configuration 3 is recommended for use in energy absorber applications in unmanned aerial vehicles due to its superior crashworthiness performance. Moreover, in hybrid-design multi-cell energy absorbers, the selection of layer geometries significantly influences deformation capability. Compared to the single-cell circular configuration (Configuration 1), Configuration 3 demonstrated superior crashworthiness performance by increasing the MCF, EA, and SEA values by 7.47, 4.47, and 1.41 times, respectively
Development of Deployable Hexagonal Module for an Arch Type Structure
No full textAraştırma, mimari tasarımda esneklik ve uyarlanabilirlik sağlayan açılabilir yapıların tarihsel gelişimini ve günümüz mimari anlayışındaki yerini incelemektedir.Araştırma, dönüştürülebilir sistemlerin tarihsel geçmişini ele alarak mimarlık tarihinde 'açılabilir' kavramının evrimini kapsamlı bir şekilde analiz etmekte ve bu sistemlerin farklı perspektiflerden ele alınma biçimlerini incelemektedir.Araştırma, açılabilir yapının bir alt türü olan düz makas yapısına odaklanmaktadır. Düz makas yapının asimetrik altıgen oluşumlar gibi yapısal oluşumlarda nasıl uygulandığı ve bu sistemlerin bir kemer modeline nasıl dönüştüğü konusunda ayrıntılı bir doğrulama süreci yürütülmüştür. Bu bağlamda, düz makas yapı birimlerinden asimetrik altıgen bir modelin oluşumu ve bu modelin bir kemer formuna dönüşüm süreçleri analiz edilmiş, yapısal özellikleri belirlenmiş ve çalışma aralıkları tanımlanmıştır. Araştırmada Niels De Temmerman tarafından önerilen daire paketi metodolojisi kullanıldı ve bu metodolojinin düz makas yapıları üzerindeki etkisi ortaya çıkarıldı. Bulgular, düz makas yapıların tasarımında kullanılan daire paketi metodolojisinin sunduğu esneklik ve uyarlanabilirlik fırsatlarını vurgulamaktadır; ve düz makas yapıların tasarım ve optimizasyon süreçlerine katkıda bulunma potansiyelini göstermektedir. Bu çalışmanın gelecekteki mimari projelerde daha işlevsel ve yenilikçi yollarla açılabilir yapının uygulanması için temel oluşturması beklenmektedir.This study aims to examines the historical development of deployable structure that provide flexibility and adaptability in architectural design and their place in today's architectural understanding. It comprehensively analyzes the evolution of the concept of 'deployable' in architectural history by addressing the historical background of transformable systems and examines how these systems are addressed from different perspectives. The research focuses on straight scissor units, which are a subtype of deployable structure. A detailed verification process has been carried out on how straight scissor units are applied in structural formations such as asymmetric hexagonal formations and how these systems transform into an arch model. In this context, the formation of an asymmetric hexagonal model from straight scissor units and the transformation processes of this model into an arch form were analyzed, their structural properties were determined and working ranges were defined. The circle package methodology proposed by Niels De Temmerman was used in the research and the effect of this methodology on straight scissor units was revealed. The findings highlight the flexibility and adaptability opportunities offered by the circle package methodology used in the design of straight scissor units; and demonstrate its potential to contribute to the design and optimization processes of straight scissor units. It is expected that this study will form the basis for the application of deployable structure in more functional and innovative ways in future architectural projects
Measurements of Flow Characterization Revealing Transition to Turbulence Associated With the Partial Flexibility-Based Flow Control at Low Reynolds Number
No full textGenc, Mustafa Serdar/0000-0002-6540-620XIn order to comprehend the flow characteristics of both controlled and uncontrolled SD7062 wind turbine airfoils with local flexible membrane material throughout a variety of angles of attack at a Reynolds number of 1.05 x 105, an experimental investigation was conducted. The time-dependent force measurement, the hot-wire experiment with a boundary layer and glue-on probes, and the oil-flow visualization technique were all utilized in the present study to measure the flow over the airfoil and examine the laminar-turbulent transition, laminar separation bubble, and the impact of a special flow control method that uses flexibility. A comprehensive intermittency analysis by utilizing hot-wire results was employed to obtain the flow physics effects of the local flexibility the first in the literature. The key results of the experiment demonstrated that the stall was delayed from alpha = 10 degrees to 12 degrees by the local flexibility. The hot-wire results are dedicated to laminar, transitional and turbulent regions and the transition phenomena at different locations over the suction surface of the airfoil in the analysis graphs. As demonstrated by the results of the oil-flow visualization experiment, in the uncontrolled case, the laminar separation bubble formed over the airfoil at alpha = 8 degrees between x/c = 0.16 and x/c = 0.42. The use of flexible membrane material over the airfoil provided that the oscillation of this material triggered the transition to turbulence and a bypass transition, which resulted in the reattached flow.Scientific Research Projects Unit of Erciyes University [FDK-2019-8726]; Scientific and Technological Research Council of Turkey (TUBITAK)The authors thank the Scientific Research Projects Unit of Erciyes University under the contract numbers: FDK-2019-8726 for funding, and also thank the Scientific and Technological Research Council of Turkey (TUBITAK) for the Doctoral Scholarship for Priority Areas 2211/C for the author Kemal KOCA
Development of a Sustainable Biofungicide Against Plant Pathogens Using Trichoderma Harzianum Cultivated on Agro-Industrial Waste
No full textTarım uygulamaları, birçok endüstri için özellikle de gıda üretimi için hayati öneme sahiptir. Tarımsal ürünler, yetiştirme sürecinden tüketime kadar olan tedarik zinciri boyunca her yıl %80 ürün kaybıyla sonuçlanabilen çeşitli zorluklarla karşılaşmaktadır. Ürün kaybını en aza indirmek için çeşitli çözüm stratejileri geliştirilmiş olsa da yaygın olarak kullanılan kimyasal ürünler canlılara ve çevreye zarar vermektedir. Kimyasalların yan etkilerini ortadan kaldırmak için biyolojik alternatiflerin kullanımı önemle teşvik edilmektedir. Trichoderma harzianum, mikoparazitizm, besin ve alan için rekabet avantajı ve antimikrobiyal sekonder metabolit üretimi gibi antagonistik aktiviteleri ile bitki gelişimini destekleyici özellikleri sayesinde iyi bilinen bir biyokontrol ajanıdır. Bu çalışmada, T. harzianum'un, Fusarium solani, Rhizoctonia solani, Aspergillus welwitschiae, Colletotrichum coccodes ve Botrytis cinerea olmak üzere beş fitopatojene karşı antifungal aktiviteleri ortaya konulmuştur. Ayrıca, T. harzianum tarafından üretilen uçucu ve uçucu olmayan organik bileşiklerin söz konusu patojenler üzerindeki etkileri değerlendirilmiştir. En güçlü inhibisyon %96,76 ile C. coccodes'e karşı gözlemlenmiştir, benzer şekilde diğer fitopatojenlere karşı da umut verici antagonistik aktivitesi bulunmuştur. Bitki gelişimini teşvik edici özellikleri de incelenmiş ve indol-3-asetik asit ile siderofor üretimi gözlemlenmiştir. Bunun yanı sıra, T. harzianum'un inkübasyonu için sürdürülebilir ve çevre dostu bir yaklaşım olarak, ayrıca tarımsal-endüstri atıklarının değer kazanımına ve döngüsel ekonomiye katkı sağlayan elma posası bazlı bir besiyeri ortamı oluşturulmuştur. Elde edilen bulgular, T. harzianum'un çevre dostu bir biyofungisit ve biyogübre adayı olarak tarımda kullanılabilirliğini desteklemektedir. Anahtar kelimeler: Biyofungisit, T. harzianum, Elma Posası, Fitopatojenler, MikoparazitizmAgricultural practices are crucial for many industries, particularly for food production. Agricultural crops face various challenges throughout the supply chain, from cultivation to consumption, resulting in up to 80% crop loss each year. Several solution strategies have been developed to minimize crop loss. However, chemical products, which are commonly used to combat phytopathogens, exhibit harm to living organisms, nature, water resources, and soil structure. The use of biological alternatives is promoted to eliminate the side effects of chemicals. Trichoderma harzianum is a well-known biocontrol agent with its antagonistic activities through mycoparasitism, competition for nutrients and space, and the production of antimicrobial secondary metabolites, while simultaneously promoting plant growth. In this study, the antifungal activities of T. harzianum against five phytopathogens, which are Fusarium solani, Rhizoctonia solani, Aspergillus welwitschiae, Colletotrichum coccodes, and Botrytis cinerea, were demonstrated. Additionally, the effects of both non-volatile and volatile organic compounds produced by T. harzianum were tested against these phytopathogens. The strongest inhibitory activity was 96.76% against C. coccodes, similarly there were promising antagonistic activity against other phytopathogens. Its growth-promoting properties were also assessed, and indole-3-acetic acid and siderophore production was observed. Moreover, the cultivation of T. harzianum was conducted on a medium based on apple pomace for a sustainable and environmentally friendly approach, contributing to the circular economy and valorization of the agro-industrial waste. These findings highlight the potential of T. harzianum as an eco-friendly alternative to chemical fungicides and as a plant growth-promoting agent in sustainable agriculture. Keywords: Biofungicide, T. harzianum, Apple Pomace, Phytopathogens, Mycoparasitis
Türkiyede Seçmen Karmaşıklığı ve Oy Verme Davranışı
No full textBu çalışmanın amacı, MacDonald, Rabinowitz ve Listhaug’ın (1995) seçmen karmaşıklığı ile parti rekabetine dair uzamsal teoriye ilişkin iki rakip model olan yakınlık modeli ve yön modeli arasında bir bağlantı öneren argümanlarını test etmektir. Yazarlar, yakınlık modelinin yön modeline göre daha bilişsel açıdan zorlu olduğundan, eğitimli ve siyasi olarak ilgili seçmenlerin oy davranışlarını anlamak için ilk modelin ikinci modele göre daha uygun bir formül sunduğunu ileri sürmüşlerdir. Yazarlar bu argümanı destekleyen bir kanıt bulamamış olsalar da, biz bu sonucun yazarların vaka seçimi ve metodolojik tercihlerinden kaynaklanabileceğini önermekteyiz. Eğitim seviyeleri arasındaki farkların belirgin ve yaygın olduğu Batı dışı bir ülkede farklı bir tablonun ortaya çıkabileceğini düşünülmektedir. Dahası, siyasi karmaşıklığı eğitim ve siyasi bilginin çarpımıyla oluşturulan alternatif bir ölçümünü kullanmaya karar verdik. Bu tür bir ölçümün siyasi karmaşıklığın daha objectif bir göstergesi olduğu varsayılmaktadır. Bu amaçla, Türkiye için 2015 yılına ait Karşılaştırmalı Seçim Sistemleri Çalışması (CSES) verilerini kullanılmıştır. Nihai veri seti, Türkiye'de en çok oy alan dört siyasi partinin Adalet ve Kalkınma Partisi (Ak Parti), Cumhuriyet Halk Partisi (CHP), Milliyetçi Hareket Partisi (MHP) ve Halkların Demokratik Partisi (HDP) seçmenlerinden oluşan 249 katılımcının yanıtlarını içermektedir. Bulgular, orijinal argümanı kısmı olarak doğrulayan kanıtlar sunmaktadır
