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Complementary regional energy features for spoofed speech detection
No full textAutomatic speaker verification systems are found to be vulnerable to spoof attacks such as voice conversion, text-to-speech, and replayed speech. As the security of biometric systems is vital, many countermeasures have been developed for spoofed speech detection. To satisfy the recent developments on speech synthesis, publicly available datasets became more and more challenging (e.g., ASVspoof 2019 and 2021 datasets). A variety of replay attack configurations were also considered in those datasets, as they do not require expertise, hence easily performed. This work utilizes regional energy features, which are experimentally proven to be more effective than the traditional frame-based energy features. The proposed energy features are independent from the utterance length and are extracted over nonoverlapping time-frequency regions of the magnitude spectrum. Different configurations are considered in the experiments to verify the regional energy features' contribution to the performance. First, light convolutional neural network - long shortterm memory (LCNN - LSTM) model with linear frequency cepstral coefficients is used to determine the optimal number of regional energy features. Then, SE-Res2Net model with log power spectrogram features is used, which achieved comparable results to the state-of-the-art for ASVspoof 2019 logical access condition. Physical access condition from ASVspoof 2019 dataset, logical access and deep fake conditions from ASVspoof 2021 dataset are also used in the experiments. The regional energy features achieved improvements for all conditions with almost no additional computational or memory loads (less than 1% increase in the model size for SERes2Net). The main advantages of the regional energy features can be summarized as i) capturing nonspeech segments, ii) extracting band-limited information. Both aspects are found to be discriminative for spoofed speech detection.TUBITAK [121E057]Acknowledgment This work was supported by TUBITAK under project no. 121E057
Comprehensive characterizations of organoclay types based on their integration to poly (butylene terephthalate) nanocomposites
No full textPolybutylene terephthalate (PBT) nanocomposites loaded with two different types of organoclays are fabricated using the melt mixing technique in a twin-screw extruder. Quaternary ammonium salts with dimethyl, benzyl, hydrogenated tallow, and dimethyl, dehydrogenated tailed modified organoclays are blended with PBT matrix at the compositions of 1%, 3%, 5%, and 10% weight ratios. Test samples are shaped using a lab-scale injection molding device. Mechanical, thermo-mechanical, thermal stability, melt flow, structural, and morphological behaviors of the nanocomposite samples are investigated by performing tensile, impact, and shore hardness tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow rate measurements, X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM) methods, respectively. According to the findings, NC 130 clay gave better results than NC 140 in terms of tensile, hardness, and melt flow behaviors, whereas NC 140 showed higher performances as impact resistance, thermo-mechanical, and density, since the reduction in density and weight lowering are highly required for mainly transportation sector, and thermal properties were considered
TÜRKÇE YARKENT BELGELERİ
No full textOrijinal künyesi E, Marcel (1984). The Turkish Yarkand Documents. Bulletin of the School of Oriental and African Studies, University of London, Vol. 47, No. 2, (1984), pp. 260-301. olan makale Prof. Dr. Marcel Erdal’ın yardımıyla ve kontrolünde çevrilmiştir. Ayrıca yazar tarafından GÜNCEL bilgiler de eklenerek YENİLENMİŞTİR. Makalede, Yarkent bölgesinden 11. yy sonlarına ait birkaç arazi satış belgesi bulunmaktır. Bu belgeler bilinen en eski hukuk belgeleri olduğundan oldukça önemlidir. Ayrıca buradaki belgeler Müslüman Türk yazısının da en eski örnekleridir. Önceki okumalar ve anlamlandırmalar da göz önünde bulundurularak belgeler yeniden incelenmiştir
Discovering new genes for alfalfa (Medicago sativa) growth and biomass resilience in combined salinity and Phoma medicaginis infection through GWAS
No full textSalinity and Phoma medicaginis infection represent significant challenges for alfalfa cultivation in South Africa, Europe, Australia, and, particularly, Tunisia. These constraints have a severe impact on both yield and quality. The primary aim of this study was to establish the genetic basis of traits associated with biomass and growth of 129 Medicago sativa genotypes through genome-wide association studies (GWAS) under combined salt and P. medicaginis infection stresses. The results of the analysis of variance (ANOVA) indicated that the variation in these traits could be primarily attributed to genotype effects. Among the test genotypes, the length of the main stem, the number of ramifications, the number of chlorotic leaves, and the aerial fresh weight exhibited the most significant variation. The broad-sense heritability (H-2) was relatively high for most of the assessed traits, primarily due to genetic factors. Cluster analysis, applied to morpho-physiological traits under the combined stresses, revealed three major groups of accessions. Subsequently, a GWAS analysis was conducted to validate significant associations between 54,866 SNP-filtered single-nucleotide polymorphisms (SNPs) and seven traits. The study identified 27 SNPs that were significantly associated with the following traits: number of healthy leaves (two SNPs), number of chlorotic leaves (five SNPs), number of infected necrotic leaves (three SNPs), aerial fresh weight (six SNPs), aerial dry weight (nine SNPs), number of ramifications (one SNP), and length of the main stem (one SNP). Some of these markers are related to the ionic transporters, cell membrane rigidity (related to salinity tolerance), and the NBS_LRR gene family (associated with disease resistance). These findings underscore the potential for selecting alfalfa genotypes with tolerance to the combined constraints of salinity and P. medicaginis infection.Tunisian-South African project; Tunisian Ministry of Higher Education and Scientific Research; FP7-ArimNet project REFORMA - Governments of Italy, Algeria, Morocco and Tunisia; [LR15 CBBC02]The authors declare financial support was received for the research, authorship, and/or publication of this article. This research was funded by the Tunisian-South African project (2019-2024) and the Tunisian Ministry of Higher Education and Scientific Research (LR15 CBBC02). The plant material was generated by the FP7-ArimNet project REFORMA funded by the Governments of Italy, Algeria, Morocco and Tunisia
Kavite içerisine konumlandırılan ikili ve döndürülen silindirden meydana gelen doğal ve zorlanmış taşınım
No full textLisansüstü Eğitim Enstitüsü, Makine Mühendisliği Ana Bilim DalıBu tez, bir kavite içerisine yerleştirilen iki ısıtılan silindirden meydana gelen doğal ve zorlanmış taşınımın kapsamlı bir incelemesini sunmaktadır. Araştırma, sıcaklık farkları nedeniyle meydana gelen doğal konveksiyon akımları ile akışın ve silindirlerin dönmesinin neden olduğu zorlanmış konveksiyon etkileri arasındaki karmaşık etkileşimi ele almaktadır. Hesaplamalı akışkanlar dinamiği (CFD) simülasyonlarından yararlanarak, elde edilen akış alanı ve ısı transferi oranlarını incelenmiştir. Bulgular, silindirlerin dönüşünün konveksiyon ile ısı transfer mekanizmaları üzerinde derin bir etkiye sahip olduğunu ve bu durumun termal performansı artırdığını ortaya koymaktadır. Özellikle, kavitede meydana gelen akış dinamiklerini önemli ölçüde değiştirerek daha etkili bir termal dağılımı sağlamaktadır. Bu bağlamda, sabit ısı akısına sahip iki silindir, adyabatik duvara sahip havalandırmalı kavitenin merkezine yerleştirilmiştir. Silindirlerin dönmediği veya sürekli olarak aynı veya zıt yönlerde döndüğü senaryolar için simülasyonlar gerçekleştirilmiştir. Ayrıca, silindirler arasındaki mesafe değişimlerinin termal performans ve akış yapıları üzerindeki etkileri de incelenmiştir. Bu çalışmada, Reynolds sayısı 100-300 aralığında, Grashof sayısı ise 103 ve 105 aralığında değişmektedir. Sonuçlar, silindirlerin döndürülmesinin ısı transfer oranını önemli ölçüde artırdığını göstermiştir. Silindirlerin döndürülmesi durumunda, birinci silindir için yaklaşık %21, ikinci silindir için ise yaklaşık %90 oranında bir ısı transferi artışı gözlemlenmiştir. Anahtar Kelimeler: Taşınım, Kavite, SilindirThis thesis presents a comprehensive investigation of the mixed convection phenomena from two hot cylinders situated within a vented cavity. The research addresses the intricate interplay between natural convection currents induced by temperature gradients and forced convection effects resulting from the ventilation of the cavity and the cylinder's rotation. Employing computational fluid dynamics (CFD) simulations, the results meticulously examined the resultant flow field and heat transfer rates. The findings reveal a profound influence of the cylinder's rotation on the convective heat transfer mechanisms, leading to enhanced thermal performance. Notably, the venting configuration significantly alters the flow dynamics, facilitating more effective thermal dissipation. In this context, two cylinders with fixed heat fluxes are positioned at the center of ventilated cavity having adiabatic wall. Simulations have been conducted for scenarios where the cylinders remain stationary or rotate continuously in the same or opposing directions. Furthermore, the effect of variations the space between the cylinders on thermal performance and flow structures have been explored. Reynolds number and Grashof number vary from 100 to 300 and from 103 to 105 , respectively. The results showed that rotating the cylinders significantly improves the heat transfer rate through the cylinders. Upon rotation of the cylinders, an enhancement in heat transfer of approximately 21% is observed for the first cylinder, while the second cylinder exhibits an improvement of about 90%. Keywords: Cavity, Cylinders, Mixed convection, Natural convection, Forces convectio
Investigation into the use of novel pretreatments in the fermentation of Alaria esculenta by Lactiplantibacillus plantarum and kombucha SCOBY
No full textHigh pressure processing (HPP), ultrasound probe (USP) and ultrasound bath (USB) were applied to Alaria esculenta as a fermentation pre-treatment. Seaweed was then fermented by Lactiplantibacillus plantarum (LAB) or symbiotic culture of bacteria and yeast (SCOBY). Physiochemical properties of fermented seaweed were measured. pH was significantly different (p 0.05). There was a significant difference (p 0.05) from seaweed powder. The control sample had the highest levels of tropomyosin (15.92 mg/kg) followed by HPP samples.University College Dublin (UCD); China Scholarship Council (CSC); Ireland's European Structural and Investment Programmes; Science Foundation Ireland [16/RC/3889]; European Regional Development FundThe authors would like to acknowledge the following fundings that support this study including UCD-CSC Scholarship Scheme supported by University College Dublin (UCD) and China Scholarship Council (CSC) and BiOrbic SFI Bioeconomy Research Centre, which is funded by Ireland's European Structural and Investment Programmes, Science Foundation Ireland (16/RC/3889) and the European Regional Development Fund. The authors would like to thank Dulra for their support and contribution of seaweed for research
Flow and heat transfer analysis of submerged multiple synthetic jet impingement in a square channel with forced-flow
No full textThis study experimentally and numerically investigated the flow and heat transfer of submerged multiple synthetic jet impingement in forced crossflow in a square-section channel with a constant heat flux on the bottom surface. In the forced channel flow, effects on heat transfer of six synthetic jets placed diagonally in the main flow have four different amplitudes and six different frequencies at various Reynolds numbers (6000 <= Re <= 40000) were examined. Jets were submerged vertically into the main flow and their effects on heat transfer in the turbulent regime of the main flow were analyzed. Temperature measurements were made using thermocouples placed at the channel entrances and exits on the target surface. The Nusselt numbers (Nu) were calculated using the measured temperatures. The results indicate that at Re = 6000, the target surface temperature decreases significantly with increasing amplitude and frequency, and the effects of amplitude and frequency on surface temperatures decreased at increasing Reynolds numbers. It was observed that the THP values increased with increasing amplitude and frequency for all Reynolds numbers tested. For a constant jet parameter (Ao = 0.88 and Wo = 27), the highest THP was determined as 2.06 at Re = 6000
Beyond Technical Specs: Using AHP to Prioritize User Needs in Turkish Basketball Arena Designs
No full textBasketball arenas are crucial spaces that must meet specific standards to ensure the sustainability of the sport and the quality of play. While Post-Occupancy Evaluation (POE) assesses these standards, it often assumes that all performance indicators are equally important, potentially leading to a gap between design intent and actual user experience. This study aims to bridge this gap by using the Analytic Hierarchy Process (AHP) to prioritize evaluation criteria for Turkish professional basketball arenas designed for national and international matches, regional/local competitions, and training programs. Existing studies and reports indicate that basketball arenas in Turkey often fall short in meeting necessary physical requirements and exhibit performance deficiencies. To address this gap, this study identifies factors determining arena performance, categorized as technical, functional, and behavioral based on Preiser's framework. These criteria were further categorized according to different spaces within the arena, including general use areas, administrative spaces, and athlete-specific areas. A panel of expert sports facility design professionals provided judgments about the relative importance of these criteria using pairwise comparisons. The AHP method was then employed to calculate priority weights for each criterion. The results reveal the relative importance of different criteria for each space. For example, in general use areas, furniture suitability/sufficiency and provision of ergonomic conditions for the disabled ranked highest. In administrative spaces, fire protection and accessibility were deemed most important, while in athlete-specific areas, visual and auditory privacy and security took precedence. This study demonstrates the potential of AHP for developing a systematic and reliable framework for qualitative evaluations that measure user satisfaction. AHP-based evaluation models offer a valuable tool for architects, facility managers, and decision-makers to assess architectural design quality, prioritize design criteria, and support user-centered design processes
Kuşakların (X, Y, Z) chatbot ve Metaversde chatbot kullanım farklılıkları
No full textLisansüstü Eğitim Enstitüsü, İşletme Ana Bilim DalıBu çalışma, farklı kuşakların temsilcisi olan tüketicilerin Chatbot kullanımının ve metaverse'de Chatbot kullanımının ile ilgili tutumlarının, tüketici davranışları ile olan ilişkisini ortaya koymak amacıyla yapılmıştır. Chatbotlar, kullanıcılarla sohbet eden ve bilgi ve destek sağlama, rezervasyonları onaylama ve temel müşteri sorularını yanıtlama gibi belirli işlevleri yerine getiren yapay zeka destekli programlardır. Örneklem büyüklüğü X, Y ve Z kuşaklarından 600 katılımcıdan oluşmuştur. Çalışmada yeni teknolojilerin gelişimi, yanı sıra kuşaklar arasında kullanım farklılıkları araştırılmış ve kuşaklar arasında farklılık olduğu belirlenmiştir. Chatbot kullanımını etkileyen faktörleri belirlemek için açıklayıcı faktör analizi yapılmış ve varyansın %56,4'ünü açıklayan 4 faktör elde edilmiştir (teknoloji meraklısı ve yenilikçi, heyecanla karar verici- müşteri odaklı, şüpheci kullanıcı, açık fikirli olanlar). Sonuçlar, chatbot kullanımının ve metaverse'de chatbot kullanımının orta düzeyde olduğunu gösterirken, bazı mal ve hizmetlerin satın alımında (ev aletleri, aksesuarlar, mobilya, dekorasyon, online alışveriş, telekomünikasyon, turizm, eğitim ve sağlıkta) kullanımın düşük düzeyde olduğu belirlenmiştir. Kuşaklar arasında metaverse'de chatbot kullanımı ve chatbot kullanım farklılığı Z kuşağında istatistiksel olarak anlamlı farklılık göstermiştir. Ayrıca chatbot ve metaverse kullanımında, 4 faktör ile satin alma davranışları arasında ilişkide sadece açık fikirlilik alt boyutu ile online alışverişe yönelik tüketici davranışı arasında istatistiksel olarak anlamlılık belirlenmiştir. Bulgular, chatbot teknolojisinin tüketici davranışındaki rolünün yüksek olmadığını göstermekte, tüketicilerin çevrimiçi alışveriş sitelerinde zihinsel kontrolün olması, içgörü ve kullanım deneyimi yaşatmasının chatbot kullanımını teşvik ettiğini ortaya koymaktadır. Bu deneyimlerin yaygınlaşması, kullanım kolaylıklarının sağlanması ve sürekli iyileştirilmenin yapılması cahatbot kullanımını sınırlı alanlardan çıkaracaktır. Ayrıca kuşaklar arasında kullanım farklılıklarının dikkate alınarak özel etkileşim stilleri ve içeriğe sahip sohbet robotları oluşturmak faydalı olacaktır.This study was conducted to reveal the relationship between the use of chatbots by consumers from different generations and their attitudes towards the use of chatbots in the metaverse and their consumer behavior. Chatbots are AI-powered programs that chat with users and perform specific functions such as providing information and support, confirming reservations, and answering basic customer queries. The sample size consisted of 600 participants from Generations X, Y and Z. In the study, the development of new technologies, as well as usage differences between generations were investigated and it was determined that there were differences between generations. Exploratory factor analysis was conducted to determine the factors affecting chatbot usage and 4 factors were obtained (Tech-savvy, innovative and efficient; Excited decision-maker, Tech-skeptical, and worry from chatbot; Open-minded and tech-adaptable) explaining 56.4% of the variance. The results show that the use of chatbots and the use of chatbots in the metaverse is at a moderate level, while the use of chatbots for the purchase of some goods and services (household appliances, accessories, furniture, decoration, online shopping, telecommunications, tourism, education and health) is at a low level. The difference in chatbot use and chatbot usage in the metaverse between generations showed a statistically significant difference in Generation Z. In addition, in the use of chatbot and metaverse, statistical significance was determined only between the open-mindedness sub-dimension and consumer behavior towards online shopping in the relationship between 4 factors and purchasing behavior. The findings show that the role of chatbot technology in consumer behavior is not high, and that consumers' mental control, insight and usage experience on online shopping sites encourage the use of chatbots. Expanding these experiences, providing ease of use and continuous improvement will take the use of chatbots out of limited areas. In addition, it would be useful to create chatbots with special interaction styles and content, considering the differences in usage between generations