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Similarity and consimilarity of hyper-dual generalized quaternions
Full text linkThe aim of this paper is to investigate similarity and consimilarity of hyper-dual generalized quaternions and their matrices. For this purpose, we give different conjugates according to the generalized quaternionic units i,j,k. We present i-consimilarity of hyper-dual generalized quaternions and their matrices except hyper-dual (1)/(4)-quaternions. For the generalization consisting of hyper-dual coefficients quaternion and split quaternion, we search j-consimilarity and k-consimilarity with the help of j-conjugate and k-conjugate. We also give i,j,k-coneigenvalues and i,j,k-coneigenvectors of the matrices of these generalizations. In addition, we examine right coneigenvalue problem in generalized quaternion matrices for real and split quaternions. The complex matrix representation obtained through the complex adjoint matrix representation of this generalization is introduced, and its properties are presented. Besides, we give algebraic methods for the concept of right coneigenvalues and coneigenvectors for matrices, which are the generalization of real quaternion and split quaternion.Yasemin Alagoz: Writing-original draft; conceptualization; methodology. Gozde ozyurt: Writing-original draft; conceptualization; methodology
Development of a Measurement-Based Computational Method for Determination of Vehicle-Induced Road Loads on Railways and Its Analysis in a Simulation Environment
Full text link222M001Demiryolu taşıtlarının hareketi sırasında, taşıtın hızı, kütlesi, tekerlek, ray ve yol geometrisi, sürtünme katsayısı gibi parametrelerin etkisiyle tekerlek-ray temas bölgesinde raylara dinamik bir etki oluşmaktadır. Raya yanal ve düşey yönde etkiyen bu kuvvetler rayı tasarım geometrisinden sapmaya zorlar ve derayman riski doğurur. Özellikle kurplarda meydana gelen yanal kuvvetler deraymanın en büyük sebeplerindendir. Bu nedenle raylara etkiyen tekerlek kuvvetlerinin anlık olarak takip edilebilmesi özellikle demiryollarını ilk hizmete alırken oldukça önemlidir. Ayrıca, demiryollarında zamanla yaşanan deformasyonlar nedeniyle ortaya çıkabilecek deraymanın önüne geçmek için yol bakım çalışmalarının zamanında yapılması hayati öneme sahiptir. Doğru ve etkin bakım çalışması yapabilmek için de raya etkiyen kuvvetlerin periyodik olarak izlenmesi önemlidir. Bu çalışmada, raya etkiyen yanal ve düşey kuvvetlerin anlık olarak belirlenebilmesi için, araç üzerinden yapılacak çeşitli ölçümlerle elde edilecek verilerin çeşitli hesaplamalarla işlenerek kullanıldığı yeni bir yöntem geliştirilmiştir. Bu yöntemde kullanılacak hesaplama denklemleri Newton’un ikinci yasası kullanılarak elde edilmiştir. Denklemin içerisinde işlenecek değişkenler ise süspansiyon sapmaları, boji gövdesi ve tekerlek seti ivmeleri gibi anlık değişen parametrelerdir. Araç üzerinde ölçülen bu ve benzeri verilerin denklemlerde kullanılması sonucu raya etkiyen yanal ve düşey kuvvetlerin belirlenmesi hedeflenmiştir. Saha testleri öncesinde oluşturulan metodun doğruluğunu araştırmak için profesyonel projelerde ve akademide yaygın olarak kullanılan SIMPACK çoklu gövdeli dinamik simülasyon yazılımında aynı araç ve yol modeli oluşturulmuştur. Aynı zamanda, analitik metotla geliştirilen dinamik denklemler MATLAB/Simulink programında modellenmiştir. Her iki model (analitik ve sayısal) ile yapılan eş simülasyonlar sonucunda elde edilen düşey ve yanal tekerlek temas kuvvet çıktıları, geliştirilen denklemlerin tutarlı olup olmadığını görmek amacıyla karşılaştırılmıştır. Simülasyonlarda taşıtın 60 km/sa hızla düz yolda ilerlediği ve aynı hızla 200 metre yarıçaplı 14 cm dever yüksekliğe sahip bir kurptan geçtiği varsayılmıştır. Her iki modelden elde edilen simülasyon çıktıları karşılaştırıldığında, düz yolda yanal ve düşey tekerlek temas kuvvetlerinin %99’un üzerinde, kurpta ise yanal tekerlek temas kuvvetinin %94’ün ve düşey tekerlek temas kuvvetlerinin de %97’in üzerinde tutarlı sonuçlar elde edildiği görülmüştür. Ayrıca, geliştirilen denklemlerin içerisinde kullanılan değişkenlerin saha ölçümlerinde araç üzerinden ölçülebilecek nitelikte olduğu ortaya konmuştur. Bu bakımdan, literatüre şehir içi demiryolu hatlarında araçlardan raylara etkiyen kuvvetlerin anlık olarak izlenebilmesini sağlayan uygulanabilir bir yöntem kazandırılmıştır.During the movement of railway vehicles, a dynamic effect occurs on the rails in the wheel-rail contact zone due to the effect of parameters such as vehicle speed, mass, wheel, rail and road geometry and friction coefficient. These forces acting on the rail in lateral and vertical directions force the rail to deviate from its design geometry and cause the risk of derailment. Especially the lateral forces occurring in curves are one of the biggest causes of derailment. For this reason, it is very important to be able to monitor the wheel forces acting on the rails instantaneously, especially when the railways are first put into service. In addition, it is vital that track maintenance works are carried out in a timely manner in order to prevent derailment that may occur due to deformations in railways over time. In order to perform accurate and effective maintenance work, it is important to periodically monitor the forces acting on the rail. In this study, a new method has been developed to determine the lateral and vertical forces acting on the rail instantaneously by processing the data to be obtained from various measurements on the vehicle with various calculations. The calculation equations to be used in this method are obtained using Newton's second law. The variables to be processed in the equation are instantaneously changing parameters such as suspension deflections, bogie body and wheel set accelerations. By using such data measured on the vehicle in the equations, it is aimed to determine the lateral and vertical forces acting on the rail. In order to investigate the accuracy of the method before the field tests, the same vehicle and track model was created in SIMPACK multi-body dynamic simulation software, which is widely used in professional projects and academia. At the same time, the dynamic equations developed by the analytical method were modeled in MATLAB/Simulink. The vertical and lateral wheel contact force outputs obtained from the simulations with both used models (analytical and numerical) were compared to see if the developed equations are consistent. In the simulations, it is assumed that the vehicle travels on a straight track at a speed of 60 km/h and passes through a curve with a radius of 200 meters and a 14 cm superelevation height at the same speed. When the simulation outputs obtained from both models are compared, it is seen that consistent results are obtained over 99% for lateral and vertical wheel contact forces on the straight road, 94% for lateral wheel contact force and 97% for vertical wheel contact force on the curve. In addition, it has been demonstrated that the variables used in the developed equations can be measured on the vehicle in field measurements. In this respect, a feasible method that enables instantaneous monitoring of the forces acting on the rails from vehicles on urban railway lines has been introduced to the literature.TÜBİTA
Practical SERS substrates by spray coating of silver solutions for deep learning-assisted sensitive antigen identification
Full text linkSurface-enhanced Raman spectroscopy (SERS) has long been recognized for its rapid and sensitive detection capabilities; however, challenges persist in practical fabrication of the substrates and interpreting complex data. Herein, we propose a deep learning (DL) assisted SERS approach to enable rapid and sensitive detection of analytes on practical yet highly effective substrates prepared by direct spray-coating of a nanoparticle-free true solution of a reactive Ag ink and on-site thermal annealing mediated generation of nanostructures. This design ensured homogeneous distribution of Ag nanostructures throughout the entire substrate, significantly increasing the number of hotspots and enhancing the Raman signals, thereby achieving an impressive analytical enhancement factor of ∼1010 in a reproducible and consistent manner. The diagnostic utility of this platform was demonstrated by detecting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein in both buffer and saliva, with detection limits of 74.3 pg/mL and 7.43 ng/mL, respectively. The DL-assisted SERS not only accurately identified the presence or absence of viral antigen, but also automatically quantified the viral load. This automatic identification achieved an outstanding accuracy of ∼99.9 %, highlighting the exceptional performance of the proposed platform. This simple, cost-effective, scalable, and ultra-sensitive DL-assisted SERS platform offers significant opportunities for early and precise detection in a range of analytical scenarios. © 2024 Elsevier B.V.SDS-PAGE; Erciyes Üniversitesi, (FOA-2023-12834); Erciyes Üniversites
A bibliometric approach to the evolution of artificial intelligence in digital marketing
Full text linkPurpose-This research aims to examine the dynamic relationship between digital marketing and AI. This study used bibliometric analysis to investigate the significance of artificial intelligence in digital marketing research. The study was conducted using the WOS database, which includes word cloud analysis, keyword analysis, citation analysis, and publication analysis. Design/methodology/approach-The present inquiry utilized the Web of Science database to gather scholarly publications that were published between 2000 and 2023. A search was performed using the Boolean operator AND to retrieve pertinent publications that contain both the terms artificial intelligence and digital marketing in the first query. A total of 96 publications were found during the search. The search terms were expanded, and the content analysis was enhanced to include studies from 1993 to 2023, resulting in 521 studies for in-depth analysis in the second query. The acquired papers were subjected to bibliometric analysis using VOSviewer software (version 1.6.20). Findings-The phrase digital marketing had the highest frequency, with a cumulative link strength of 94. This keyword exhibited a strong association with the phrase artificial intelligence. The WOS database shows a steady increase in publications on digital marketing and AI since 2017 for the first query. In 2017, there were about two publications, which grew to around 26 by 2021. For the second query, the number of publications on digital marketing and AI also increased steadily. In 1993, there was one publication, rising to about 102 by 2022. Originality/value-The study conducts a comprehensive bibliometric analysis by examining publications that were released in the Web of Science database from 2000 to 2023 for the first query and from 1993 to 2023 for the second query. This research analyzes the progress and current status of corporate management and marketing techniques during the past twenty-four years. In addition, this approach enhances the originality of the second inquiry by providing a comprehensive analysis of studies spanning nearly 3 decades, offering unique insights into the evolution of the field. The research centers on the impact that AI has exerted on these sectors. Moreover, the results of this study emphasize the significance of the increasing number of scientific studies that intersect AI and digital marketing
İstanbul Depremine Hazırlık Kapsamında 2000 Yılı Öncesi Yapılmış Betonarme Yapıların Kronik Problemleri Ve Çözüm Önerileri
No full textÜlkemiz sığ deprem etkilerinin yoğun olarak hissedildiği ve sismik aktivitenin yüksek olduğu bir coğrafyada yer almaktadır. Mevcut yapılarımızın azımsanmayacak bir bölümünün mühendislik hizmeti görmeden imal edilmiş olması nedeniyle geçmişte yaşadığımız depremler, büyük can ve mal kayıplarına sebep olmuştur. Şehirlerimizin deprem direncinin artırılması için etkili önlemler alınmadığı sürece ileriki yıllarda meydana gelebilecek muhtemel depremlerin de büyük zararlar vereceği ortadadır. Bu nedenle deprem güvenliği bilinmeyen yapılarımızın mevcut yapı stokundan ayıklanarak güncel durumlarının belirlenmesi ve deprem riskinin azaltılması için ivedilikle harekete geçilmesi gerekmektedir. Özellikle beklenen İstanbul depremi açısından 2000 yılı öncesi yapılmış yapıların deprem güvenliklerinin sorgulanması ve bu yapıların güçlendirilerek İstanbul’un deprem direncinin artırılması hususu ülkemiz geleceği açısından da büyük önem taşımaktadır. Geçtiğimiz yıllarda yaşadığımız acı tecrübelerden; 17 Ağustos 1999 Düzce depremi, 26 Eylül 2019 Silivri Depremi ve 06 Şubat 2023 Kahramanmaraş depremleri yakın tarihin en belirgin örnekleridir. Bu yazıda muhtemel İstanbul depremine hazırlık açısından önemli olan farklı güçlendirme teknikleri sunulmuştur. Söz konusu yöntemler insanların tahliyesine gerek kalmaması nedeniyle son derece rasyonel ve uygulanabilir nitelikte olduğu düşünülmektedir
Intelligent adaptive PSO and linear active disturbance rejection control: A novel reinitialization strategy for partially shaded photovoltaic-powered battery charging
Full text linkThis study aims at enhancing the performance of Conventional Particle Swarm Optimizer (CPSO) to maximize the efficiency of solar photovoltaic-powered battery chargers under partial shading (PS) conditions, making it appropriate for several applications such as wheelchairs, and electric vehicles. To address this issue, The Adaptive Particle Swarm Optimizer (APSO) strategy is used in this work. It selects weight factors based on adaptive inertia, uses reinitialization techniques to find variant global maximum peak (GMP), and modifies learning factors to maximize the speed and accuracy of CPSO convergence. The reference voltage output from APSO was then tracked using the Linear Active Disturbance Rejection Control (LADRC). The LADRC improves the maximum power point tracking (MPPT) technique's anti-interference capability against multiple external disturbances and speeds up the system's response time. The simulation and experiment findings demonstrate that hybrid APSO-LADRC overcomes the drawbacks of CPSO, offering better performance for tracking GMP effectively with less oscillations and shorter convergence time compared to CPSO, grasshopper optimization (GHO), incremental conductance (INC) and perturb & observe (P&O) during dynamic and static PS. The results demonstrate that the proposed APSOLADRC's efficiency reaches a level greater than 99 % even in PS, and it additionally demonstrates a faster rate of convergence and less oscillations in power during the entire tracking procedure. Furthermore, the PV system's robust performance highlights its capability to reliably charge batteries in applications like wheelchairs and electric vehicles, ensuring uninterrupted operation and energy efficiency even in challenging shading scenarios.King Salman center For Disability Research [KSRG-2024-056]The authors extend their appreciation to the King Salman center For Disability Research for funding this work through Research Group no KSRG-2024-056
A bibliometric review on the use of artificial intelligence in human resources management
No full textThis study aims to investigate studies on the use of artificial intelligence in human resources management in the last 10 years using the bibliometric method. By searching the keywords of "Human Resources Management", "Human Resource Management", "Human Resources", "Human Resource", "Artificial Intelligence", "Machine Learning", "Deep Learning", "Artificial Narrow Intelligence", "Artificial General Intelligence", "Artificial Super Intelligence", "Generative Artificial Intelligence", "Generative AI", and their abbreviations such as HRM, AI, and so on in the Web of Science Core Collection database on July 22, 2024, 47,955 scholar works have been accessed. The filtering process has yielded a data set consisting of 949 publications, which have been analyzed using the bibliometric analysis method by the software, VOSviewer with the version of 1.6.20. The analysis reveals leading authors and institutions with significant contributions and provides a holistic view of AI applications in HRM, highlighting both the opportunities and challenges with an interdisciplinary perspective. © 2025, IGI Global Scientific Publishing. All rights reserved
Müzelerde Teknoloji ve Yapay Zekâ Kullanımı Üzerine Yapılan Çalışmaların İncelenmesi
No full textDijitalleşme, her alanda olduğu gibi müzelerde de bireylerin ihtiyaç ve beklentilerine yönelik olarak etkisini göstermektedir. Dijitalleşme ve özellikle yapay zekâ, müzelerin işleyişi ve ziyaretçi deneyiminde değişikliklere neden olmuştur. Dijitalleşme, müzelerin koleksiyonlarını sanal ortamda erişilebilir kılarak fiziksel sınırlamaları aşmalarını sağlamıştır. Yapay zekâ ise müze rehberlik sistemlerinden, eser analizlerine kadar geniş bir alanda kullanılmakta, ziyaretçilerin tercihlerine göre kişiselleştirilmiş deneyimler sunabilmekte ve bunun yanısıra restorasyon, yönetim, veri analizi, eserlerin korunması gibi birçok imkân yaratması yaratması etkileşimin artmasında önemli bir rol oynamaktadır. Tüm bu teknolojik gelişmeler, müzeleri daha erişilebilir, etkileşimli ve sürdürülebilir hâle getirerek kültürel mirasın dijital platformlarda yeniden şekillenmesine katkı sağlamıştır. Bu bağlamda çalışmanın amacı, müzelerde teknoloji ve yapay zekâ kullanımı ile ilgili yapılan çalışmaların çeşitli değişkenlerle birlikte bibliyometrik yöntemler kullanılarak incelenmesidir. Veri tabanı olarak Web of Science (WoS) tercih edilmiştir. Araştırmanın amacı doğrultusunda arama terimi olarak
“müze, teknoloji ve yapay zekâ” kullanılmıştır. 04.02.2025 tarihinde, belge türü ve zaman kısıtlaması olmadan yapılan tarama sonucunda 399 yayın çalışma kapsamında incelenmiştir. Bibliyometrik analizin yapılmasında ve grafiklerin oluşturulmasında WoS Analysis, VOSviewer ve R Stüdyo’dan yararlanılmıştır. Bu noktada incelenen yayınlar içerisinde etkili olanların tespit edilmesi, en etkili yazarların, çalışma konularının belirlenmesi, ilgili literatürün yıllar içerisindeki gelişimi, ülkeler arası işbirliği ağı, kullanılan anahtar kelimeler ve çalışmaların tematik harita oluşturularak değerlendirilmiştir. Çalışmada sonuç olarak yayınların yıllar içinde ortaya çıkan çalışma konularının gelişimi ve değişimi incelenerek mevcut literatür ortaya konulmuştur. Müzelerde teknoloji kullanılarak oyunlaştırma, yapay zekâ destekli müze uygulamalarına yönelik ziyaretçi deneyimlerinin ölçülmesi, dijital sergilere yönelik kullanıcı tutumları ve algılarının ölçülmesi, yapay zekâ destekli müze eğitimi vb. konularda çalışmaların olmadığı veya eksiklikler olduğu belirlenmiştir
Differential loss of PRUNE2 in colorectal adenocarcinoma tissues
Full text linkColorectal cancer is of the most prevalent and deadliest cancer in the world. Cumulative evidence suggests that PRUNE is a tumor suppressor gene and plays a significant role in the development and progression of human cancers. However, its role during colorectal cancer development remains elusive. In the present study, we aimed to determine the role of PRUNE2 and its diagnostic significance in colorectal cancer. A total of 70 patients with colorectal cancer and 30 control subjects were included in the present study. All patients were confirmed to be colorectal adenocarcinoma. PRUNE2, P53, and PCNA immunoreactivity of patients were determined using standard immunohistochemistry staining techniques. Notably, PRUNE2 was identified to be significantly downregulated in colorectal cancer patients compared to the control group (p < 0.0001). Almost no immunoreactivity was observed in tumor samples compared to healthy colon tissues, where significant immunoreactivity was observed. Also, both P53 and PCNA were significantly higher in patients with colorectal cancer (p < 0.0001). Overall, our results suggest that PRUNE is a reliable and robust biomarker for the differential diagnosis of colorectal cancer and can be used for future diagnostic applications together with other immunological biomarkers such as PCNA. © The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature 2025
New 4-methanesulfonyloxy benzohydrazide derivatives as potential antioxidant and carbonic anhydrase I and II inhibitors: synthesis, characterization, molecular docking, dynamics & ADME studies
Full text linkAs an archetypal molecule, hydrazides have a crucial vital role in numerous applications, so hydrazide-related inhibitors, especially sulfur-enriched, are favored. In the present work, we designed, synthesized and characterized fifteen novel benzohydrazide derivatives containing 4-methanesulfonyloxy and arylidene building blocks with a four-step synthesis pathway. The inhibitory potential of the compounds was assessed using human carbonic anhydrases I and II (hCA I and II) isozymes and the results were compared to those of the standard inhibitor, acetazolamide (AZA). The antioxidant activity profiles for all compounds were also examined using various bioanalytical methods and the results were compared with the standards. The hCA I and II were the best inhibited by compounds 5f, 5g, and 5i with inhibition constants IC50 in the range 20.45-51.43 nM (AZA: IC50=218.38) for hCA I and 33.54-42.45 nM (AZA: IC50=44.39) for hCA II. Structure-activity relationships were also discussed and discovered that hCA I and II inhibition was unaffected by the presence of an electronwithdrawing or releasing group. This effectiveness was the only result of the sort of substituted group(s), which was located at the reagent. Molecular docking and dynamics simulations showed that compounds 5f, 5g, and 5i have strong and stable interactions with key amino acids and zinc ions in the active sites of enzymes, which supports their ability to block enzyme activity. In silico ADME studies predicted favorable drug-like properties and high human oral absorption for all synthesized compounds. In silico ADME studies predicted favorable drug-like properties and high human oral absorption for all synthesized compounds. These findings highlight the multifunctional potential of the synthesized benzohydrazide derivatives as hCA I and II inhibitors and antioxidants, paving the way for their further development and optimization for therapeutic applications.Istanbul University Scientific Research Projects Coordination Unit [TYL-2020-36795]The authors extend their appreciation to Istanbul University Scientific Research Projects Coordination Unit (Project no: TYL-2020-36795)