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ECG Arrhythmia Classification Using Vague C-Means Clustering Based on Multiresolution Analysis
No full textThe accurate classification of ECG arrhythmias is crucial for diagnosing heart diseases. The detection and classification of arrhythmia rely on several key factors, including the specialist's experience level, work intensity, and time consumption. These factors are critical determinants of the accuracy and effectiveness of the diagnostic process, which, in turn, directly impacts the patient's health outcomes. Artificial intelligence-based computer-aided diagnosis systems have made great progress in ECG arrhythmia classification in recent years. In this study, ECG arrhythmia classification was performed using a vague c-means clustering algorithm. The data set used was obtained from the MIT-BIH ECG Arrhythmia Database. The data set consisted of 318 patterns which are RR intervals Experiments were performed with different parameters of vague c-means clustering to achieve the highest classification performance. In addition, experiments were repeated using fuzzy c-means clustering for comparison. Furthermore, a frequency-based feature set using multiresolution analysis based on discrete wavelet transform was obtained. An ECG classification task was realized with vague c-means clustering on this frequency-based dataset. The best results were obtained as 87.5%, 80%, and 84% for classification accuracy, sensitivity, and positive predictive value, respectively
Geometric Optimization of a Blood Pump Impeller Using the Taguchi Method: Cfd Analysis and Experimental Evaluation
No full textRotodynamic Left Ventricular Assist Devices (LVADs) are critical in managing severe heart failure by providing mechanical circulatory support. Improving these blood pumps'efficiency is crucial for both lowering the device's energy consumption and enhancing patient comfort. In this study, the efficiency of a reference centrifugal blood pump was improved through geometric optimization and validated using computational fluid dynamics (CFD) simulations and experiments. The number of blades, inlet width, outlet width, inlet angle, and outlet angle are among the important impeller parameters that were optimized at three different levels. The orthogonal array of the Taguchi design method was used to reduce the 243 possible configurations from the full-factorial experimental design to 27 trial tests. Analysis of Variance (ANOVA) was used to determine the optimal geometric parameters, which led to maximum efficiency after S/N ratios were analyzed using MINITAB-18 software. The performance of the optimized pump was evaluated via CFD at 3300, 3150, and 3450 pump rotation speeds, resulting in a 21% increase in hydraulic efficiency at the design point (5 L/min, 3300 rpm, and 128.515 mm-Hg). Furthermore, experimental results demonstrated reduced power consumption for the optimized pump compared to the reference pump. This study highlights the potential of geometric optimization in advancing the performance of rotodynamic LVADs.This study is supported fi nancially by the Konya Technical University, Coordinatorship of Scientific Research Projects under project Grant No. 191010038.Konya Technical University, Coordinatorship of Scientific Research Projects [191010038
Search for Nuclear Modifications of (Formula Presented) Meson Production in (Formula Presented)-Pb Collisions at (Formula Presented)
No full textNuclear medium effects on (Formula presented) meson production are studied using the binary-collision scaled cross section ratio between events of different charged-particle multiplicities from proton-lead collisions. Data, collected by the CMS experiment in 2016 at a nucleon-nucleon center-of-mass energy of (Formula presented), corresponding to an integrated luminosity of (Formula presented), were used. The scaling factors in the ratio are determined using a novel approach based on the (Formula presented) cross sections measured in the same events. The scaled ratio for (Formula presented) is consistent with unity for all event multiplicities, putting stringent constraints on nuclear modification for heavy flavor. © 2025 CERN, for the CMS Collaboration.Ministry of Business, Innovation and Employment, MBIE; Ministry of Education and Science, MES; Benemérita Universidad Autónoma de Puebla, BUAP; NSC; Fundação para a Ciência e a Tecnologia, FCT; Department of Atomic Energy, Government of India, DAE; PCTI; National Academy of Sciences of Ukraine, NASU; National Science and Technology Development Agency, สวทช; National Research Foundation of Korea, NRF; MSES; Ministerio de Educación, Cultura y Deporte, MECD; National Science Foundation, NSF; Institut National de Physique Nucléaire et de Physique des Particules, IN2P3; Science and Technology Facilities Council, STFC; Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, CINVESTAV; Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, FAPERJ; Ministerio de Ciencia e Innovación, MCIN; Universiti Malaya, UM; Ministry of Science and Technology, Taiwan, MOST; Ministry of Science,Technology and Research, MoSTR; Hispanics in Philanthropy, HIP; Instituto Nazionale di Fisica Nucleare, INFN; Secretaría de Educación Pública, SEP; Austrian Science Fund, FWF; Department of Science and Technology, Ministry of Science and Technology, India, DST; Consejo Nacional de Humanidades, Ciencias y Tecnologías, Conahcyt; Centre National de la Recherche Scientifique, CNRS; Bundesministerium für Bildung und Forschung, BMBF; Fonds Wetenschappelijk Onderzoek, FWO; Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK; LMTLT; Helmholtz-Gemeinschaft, HGF; Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA; Research Council of Finland, AKA; Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq; Pakistan Atomic Energy Commission, PAEC; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES; MSIP; Türkiye Enerji, Nükleer ve Maden Araştırma Kurumu, TENMAK; Deutsche Forschungsgemeinschaft, DFG; Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, NKFIH; Ministry of Education - Singapore, MOE; Ministarstvo Prosvete, Nauke i Tehnološkog Razvoja, MPNTR; Science Foundation Ireland, SFI; U.S. Department of Energy, USDOE; Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP; Cosmetic Surgery Foundation, CSF; Agencia Estatal de Investigación, AEI; General Secretariat for Research and Innovation, GSRI; Bulgarian National Science Fund, BNSF; Direktion für Entwicklung und Zusammenarbeit, DEZA; Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie, BMBWF; Ministerio de Ciencia, Tecnología e Innovación, Minciencias; Maryland Ornithological Society, MOS; Chinese Academy of Sciences, CAS; Ministry of Higher Education, Science, Research and Innovation, Thailand, MHESRI; Fonds De La Recherche Scientifique - FNRS, FNRS; Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, FAPERGS; Shota Rustaveli National Science Foundation, SRNSF; Institute for Research in Fundamental Sciences, IPM; Laboratorio Nacional de Supercómputo del Sureste de Mexico, LNS; CERN; Secretaría de Educación Superior, Ciencia, Tecnología e Innovación, SENESCYT; Universidad Autónoma de San Luis Potosí, UASLP; National Natural Science Foundation of China, NSFC; European Research Council, ERC, (MoER TK202); European Research Council, ER
Determination of the Geotechnical Characteristics of the Excavation Waste Field Located To the Southwest of Kahramankazan (Ankara)
No full textAccording to the 50-year probability of exceedance according to the Earthquake Hazard Maps of Turkey in the southwest of Kahramankazan District of Ankara Province, the maximum ground acceleration is 0.141 g. and is located in the low-hazard earthquake zone. The cohesive and non-cohesive soils on the foundation units and their saturation with groundwater cause significant ground problems. These problems vary depending on whether the ground is dense or loose, the groundwater is close to the surface, the chemical properties of the groundwater, the ground grain size distribution, the clay content of the ground, the presence or absence of an impermeable layer of clay-dominated cover on the upper surface of the ground and the value of the pore water pressure. It is known that cohesionless soils cause many ground problems such as loss of bearing capacity, flow, sliding, lateral spreading, excessive settlement, liquefaction and similar ground problems due to groundwater and earthquake effects. Within the framework of these predictions, the properties of the soils in the study area were investigated with the stress approach and related laboratory tests using field methods such as Standard Penetration Test (SPT) in accordance with the principles of soil mechanics and engineering. In the bearing capacity calculations made as a result of the laboratory tests of the fill soils and the solid consistency alluvial soils under the fill soils, it was determined that the bearing capacity design strength was between 129 kPa and 380 kPa, the consolidation settlement amount was between 4.114 cm and 15.825 cm and the liquefaction energy potential was low-very low. In the light of these data, it was determined that the large and low-rise industrial buildings designed in the study area did not have bearing capacity, settlement and liquefaction problems. It was understood from the parcel-based studies that there were bearing capacity, settlement and liquefaction problems locally. These problems are eliminated with the rockfill improvement method in such places. Therefore, it is necessary to plan the structures depending on the obtained values. In addition, improvements should be made in the static conditions of the existing structures in a way that will minimize possible earthquake damages. Keywords: Geotechnical, Earthquake, Settlement, Liquefaction, KahramankazanAnkara İli Kahramankazan İlçesi güneybatısında, Türkiye Deprem Tehlike Haritalarından 50 yılda aşılma olasılığı %10 (tekrarlama periyodu 475 yıl) göre en büyük yer ivmesi 0.141 g. olup düşük tehlikeli deprem bölgesinde bulunan Hafriyat Atık Sahasında, temel birimler üzerinde yer alan kohezyonlu ve kohezyonsuz özellikteki zeminler ile bunların yeraltı suyuyla doygunlaşması sonucunda önemli zemin problemlerine neden olmaktadır. Bu problemler zeminin sıkı-gevşek olmasına, yeraltı suyunun yüzeye yakın olmasına, yeraltı suyunun kimyasal özelliğine, zemin tane boyu dağılımına, zeminin kil içeriğine, zeminin üst yüzeyinde kil ağırlıklı geçirimsiz bir örtü tabakasının bulunup-bulunmamasına ve boşluk suyu basıncının değerine bağlı olarak değişmektedir. Kohezyonsuz zeminler yeraltı suyu ve deprem etkisiyle taşıma gücü kaybı, akma, kayma, yanal yayılma, aşırı oturma, sıvılaşma ve benzeri birçok zemin problemlerine yol açtığı bilinmektedir. Bu öngörüler çerçevesinde inceleme alanındaki zeminlerin özellikleri, zemin mekaniği ve mühendisliği prensiplerine uygun olarak, Standart Penetrasyon Deneyi (SPT) gibi arazi yöntemlerini kullanan gerilme yaklaşımı ve ilgili laboratuvar deneyleri ile araştırılmıştır. Dolgu zeminlerin ve Dolgu zeminlerin altında yer alan katı kıvamlı Alüvyon zeminlerin Laboratuvar deneyleri sonucunda yapılan taşıma gücü hesaplamalarında taşıma gücü tasarım dayanımı 129 kPa ile 380 kPa aralığında, konsolidasyon oturma miktarının 4.114 cm ile 15.825 cm aralığında ve sıvılaşma enerjisi potansiyelinin düşük-çok düşük düzeyde olduğu belirlenmiştir. Bu veriler ışığında inceleme alanında tasarlanan geniş ve düşük katlı sanayi amaçlı yapıların taşıma gücü, oturma ve sıvılaşma problemlerinin olmadığı tespit edilmiştir. Yer yer lokal olarak taşıma gücü, oturma ve sıvılaşma problemlerinin olduğu parsel bazlı etütlerden anlaşılmıştır. Bu tür yerlerde kaya dolgu iyileştirme metodu ile bu sorunlar giderilmektedir. Bu nedenle elde edilen değerlere bağlı olarak yapıların planlanması gerekmektedir. Ayrıca olası deprem hasarlarını en aza indirgeyecek şekilde mevcut yapılarda statik durumlarında iyileştirmelerin yapılması gerekmektedir. Anahtar Kelimeler: Jeoteknik, Deprem, Oturma, Sıvılaşma, Kahramankaza
Novel Fe3O4@SiO2/Co-mo-b Core-Shell Magnetic Nanocatalyst: a Reusable System for High-Performance Hydrogen Evolution in Borohydride Hydrolysis
No full textThe present study focuses on the synthesis of a Fe3O4@SiO2/Co-Mo-B core-shell nanocatalyst, designed as a high-performance and reusable system optimized for hydrogen evolution in borohydride hydrolysis reactions. The catalytic activity and hydrogen generation rate were evaluated by varying the catalyst amount, temperature, reusability, and MOH/MBH4 wt% (M = Na, K). A range of characterization techniques, including FE-SEM, EDX, XRD, BET, XRF, TEM, XPS, and FTIR, were used to analyze the structure and composition of the samples. The Fe3O4@SiO2/Co-Mo-B nanocatalyst demonstrated exceptional catalytic performance, achieving a hydrogen generation rate of 22.6 L gmetal -1 min-1 with an activation energy of 23.72 kJ mol-1 for KBH4 hydrolysis at 50 degrees C. For NaBH4 hydrolysis, the HGR was 27.5 L gmetal -1 min-1, with an activation energy of 32.18 kJ mol-1, demonstrating its high catalytic efficiency. Reusability studies over six successive cycles confirmed the stability of the catalyst, maintaining high hydrogen yields of 99.84 %-97.29 % for NaBH4 and 95.25 %-99.09 % for KBH4 across varying concentrations, further supporting its strong potential for industrial hydrogen storage and on-demand hydrogen generation. FE-SEM analysis revealed a grape-like morphology, while TEM confirmed a uniform CoMo-B coating (18-20 nm) on the SiO2 shell, forming a robust core-shell structure that enhanced stability and durability. Additionally, the successful silica coating of Fe3O4 and effective adsorption of Co-Mo-B were validated, both of which contributed to the sustained catalytic activity of the catalyst. The remarkable performance of Fe3O4@SiO2/Co-Mo-B in NaBH4 and KBH4 hydrolysis, combined with its low activation energy and high reusability, make it as a promising candidate for sustainable and scalable hydrogen generation.This study was supported by Konya Technical University's Scientific Research Projects (BAP) Coordination Unit (Project No: 221116033) .Konya Technical University's Scientific Research Projects (BAP) Coordination Unit [221116033
Characterization of Chemical Compounds of Fractions From Four Different Bee Pollens With Chemometric Classification
No full textBee pollen continues to increase its popularity as a ‘complete food’ among natural resources with its high health value and therapeutic chemical compounds. This study focused on HPLC-DAD (high-performance liquid chromatography-diode array detection) based on the identification of chemical compounds of Cistus creticus, Helianthus annuus, Papaver somniferum and Salix sp. bee pollens. Also, water extracts and the fractions (hexane, dichloromethane, ethyl acetate, butanol, water) obtained from the methanol extracts of all bee pollens were investigated for chemical compounds. A total of 29 chemical compounds were screened and kaempferol was detected in all studied bee pollen samples at concentration of 0.4 and 331.6 µg/g. Luteolin (68.7–694.8 µg/g), trans-aconitic acid (12.2–479.1 µg/g), myricetin (160.4–1534.2 µg/g), quercetin (162.1–608.1 µg/g), rosmarinic acid (273.8–435.6 µg/g), rutin (3.6–202.8 µg/g), and trans-cinnamic acid (5.1–1854.6 µg/g) were found as the most abundant chemical compounds. Additionally, nonpolar and polar fractions of the bee pollens were chemometrically clustered for similarities and differences of chemical compounds via principal component analysis (PCA) and hierarchical cluster analysis (HCA). In nonpolar fractions, C. creticus, H. annuus, P. somniferum, and Salix sp. ethyl acetate fractions (CEA, HEA, PEA, SEA) were separated from other fractions, while in polar fractions, C. creticus, H. annuus, P. somniferum, and Salix sp. butanol fractions (CB, HB, PB, SB) were separated from other fractions. This study provides additional data on the characterization of valuable chemical compounds in bee pollens and constitutes a beginning in the chemometric classification of chemical compounds. © The Author(s) 2025.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK, (TUBITAK-122Z738); Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTA
Biocompatible Sugar Beet Molasses Carbon Dots as Potential Elicitor To Improve Bioactive Compounds of Wheatgrass Juice (Vol 24, Pg 4935, 2024)
No full textKara, Meryem/0000-0003-0893-867
Utilizing Clays From Mine Tailings and Construction and Demolition Waste in Limestone Calcined Clay Cement (LC3) Production: Grinding, Calcination and Performance Analysis
No full textWe investigate the use of low-grade and waste clays sourced from mine tailings (MT) and construction and demolition waste (CDW) stream to develop LC3 and mortars. This work is of great importance to T ; uuml;rkiye and countries alike, which are major cement producers and frequently face challenges from catastrophic earthquakes and landslides, leading to the accumulation and downcycling of large quantities of inactive MT- and CDW-based clays. Accordingly, as a novel pathway to tackle environmental and post-disaster recovery challenges, revalorization of previously downcycled or landfilled materials as alternative sources in LC3 is introduced herein. The study investigated the chemical composition, mineralogy, and physical properties of clays by using particle size distribution (PSD), X-ray fluorescence (XRF), X-ray diffraction (XRD), and thermogravimetric (TG) analysis. Clays sourced from MT were calcined at different temperatures within 450-900 degrees C range, while CDW-based ceramic tile (WCT) clay was used without calcination. Clays calcined at different temperatures were assessed through Fourier Transform Infrared Spectroscopy (FTIR). Along with the enhancement of PSD and material uniformity by hybrid grinding, viscosity and plasticity of the clays were measured by focusing on flowability. Fresh and hardened properties of the produced LC3 mixtures were compared to traditional clinker-rich CEM I 42.5R Portland cement (PC) pastes/mortars, and LC3 mixtures made from high-grade refined kaolin (RK) clay. Flow spreads of all LC3 mortars ranged between 10 and 23.5 cm compared to PC mortars with a flow spread of 23 cm. Initial and final setting times of LC3 pastes ranged between 90-145 min and 180-245 min, while the same values for PC pastes were 95 and 200 min, respectively. Fresh properties and compressive strength of all LC3 mixtures using MT and WCT clays complied with standard requirements. LC3 mortar utilizing low-grade clay, calcined at 600 degrees C and costs similar to 8 times less than high-grade RK clay, exhibited an average 7-day compressive strength of 33.8 MPa, comparable to that of RK-based LC3 mortar (33.4 MPa). Another LC3 mortar containing low-grade clay calcined at 750 degrees C exceeded the 28-day compressive strength (50.1 MPa) of PC mortar (46.9 MPa). LC3 mixtures containing WCT clay displayed the highest strength development over time, reaching a 90-day compressive strength of 53.2 MPa. Findings demonstrate the potential of utilizing MT and WCT clays for sustainable LC3 formulations by optimizing their physical, mineralogical, and thermal properties offering significant environmental benefits.Scientific and Technical Research Council of Turkiye (TUBITAK) [123M850]; Scientific Research Projects (BAP) Coordination Office [231004022]The authors gratefully acknowledge the financial assistance of the Scientific and Technical Research Council of Tuerkiye (TUEBITAK) for the project titled "Development of Limestone Calcined Clay Cement (LC 3) and Mortars with Low Quality Clays from Tuerkiye" and numbered "123M850". This publication is a part of the master thesis dissertation work by the first author in the Academic Program of Civil Engineering, Institute of Science, Konya Technical University supported by the Scientific Research Projects (BAP) Coordination Office under grant "231004022"
Surface Analysis of Erosion Resistance of Recycled Pa 3200 Gf Powders Produced by Selective Laser Sintering
No full textDemirci, Musa/0000-0002-4159-2378This paper evaluates solid particle erosion (SPE) performance of samples produced via selective laser sintering (SLS) using fully recycled PA 3200 GF material, following ASTM G76-95 standards. For this purpose, six samples (30*30*3 mm3) were printed at 0 degrees, 45 degrees, and 90 degrees in x-y and x-z planes with a 100-mu m layer thickness. SPE tests examined erosion at distinct impact angles (30 degrees, 45 degrees, 60 degrees, 90 degrees) and pressures (1, 2, 3 bars). Results showed higher particle velocities reduced erosion resistance, where 45 degrees x-y plane samples demonstrated superior resistance (erosion rates: 0.050, 0.100, 0.220 mg/g under 1, 2, 3 bars, respectively). The 30 degrees impact angle caused maximum erosion, while 90 degrees had the least. Samples positioned horizontally in the x-y plane were most sensitive to impact angles, with 10% higher erosion sensitivity than others. The study highlights how printing direction significantly affects SPE performance in SLS
Investigation and Efficiency Analysis of Dual-Boost Bridgeless PFC Converter
No full textArtan enerji tüketimi ile birlikte elektrik sistemlerinde verimlilik günden güne daha da önemli hale gelmektedir. Bu durum doğrultuculardan kaynaklanan güç kalitesi sorunlarına çözüm sunan Güç Faktörü Düzeltmeli dönüştürücülerde yüksek verim arayışını zorunlu kılmıştır. Bu çalışmada yüksek verim sunan Köprüsüz Boost PFC Dönüştürücüler incelenmiştir. Bu dönüştürücülerin olumlu ve olumsuz özellikleri sunulmuştur. Köprüsüz dönüştürücülerin bir türü olan Dual-Boost Köprüsüz PFC Dönüştürücü tanıtılmış ve dönüştürücünün PSIM ortamında simülasyonu yapılmıştır. Elde edilen giriş akımı harmonik içeriği, güç faktörü ve verimlilik değerleri, daha önceki çalışmalarımızda aynı parametrelerle tasarlanan Klasik Boost PFC Dönüştürücü ile karşılaştırılmıştır. Dual-Boost Köprüsüz PFC Dönüştürücü farklı güç seviyelerinde çalıştırılarak güç faktörünün ve toplam harmonik bozulmanın değişimi grafiksel olarak sunulmuştur. Daha detaylı bir verim analizi için dönüştürücüler farklı iletim dirençlerine sahip MOSFET'ler kullanılarak tekrar çalıştırılmıştır. Sonuç olarak Köprüsüz PFC Dönüştürücülerin verimlilik avantajı kanıtlanmıştır. Ayrıca SiC gibi düşük iletim direncine sahip MOSFET'lerin bu dönüştürücüler için önemi anlaşılmıştır