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Effects of Shear Wall Ratio and Location on Earthquake Performance of Reinforced Concrete Buildings Having Different Ribbed Slab Configurations
No full textThis study investigates the earthquake performance of reinforced concrete buildings designed with ribbed slab system. Analyses were performed on hypothetical models representing residential buildings in Gaziantep/Islahiye region. In this study, a total of 18 shear wall-frame structure models with three different shear wall placements in accordance with TBEC-2018 were analyzed. Wall density index (0.003, 0.005 and 0.008), shear wall locations defined as M1 (vertically placed on the outer axes), M2 (center-mounted), and M3 (parallel to the outer axes), and ribbed slab placements (parallel and staggered) are considered as variable parameters. The seismic performance of the structures was evaluated using linear and nonlinear analyses. Nonlinear static pushover analyses were used to compare capacity curves, overstrength factor, interstory drift ratios, base shear forces, overturning moments, and second-order effects for each model. As the wall density index increased from 0.003 (%25) to 0.008 (%75), the initial stiffness increased by 158 %, but this increase decreased the plastic deformation capacity and modal displacement values. Models M1 and M3 with walls positioned on the outer axes provided 20.53 % more load carrying capacity than Model M2 with the central wall. The uncracked section shell exhibited 19 %-83 % stiffer behavior, while the cracked sections absorbed more energy. No significant effect of the slab rib arrangement (parallel/staggered) on the stiffness and period was observed. As the shear wall ratio increased, the torsional period decreased by up to 55 %, and the highest torsional strength was achieved in Model M3. Low shear wall ratio models exceeded code drift limits and showed increased interstory drift differences. The results showed that shear wall placement and ratios are critical to seismic performance, and that TBEC-2018 effectively enhances safety in ribbed slab systems.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Declaration of Generative AI and AI-assisted technologies in the writing process during the preparation of this work, the authors used ChatGPT in order to improve several important aspects of writing, such as readability, grammar, spelling, and tone of the text. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.AI-assisted technologies in the writing proces
The Effect of the Amendment Made in the Law on Determination of Building Inspection Agency on Building Inspection System: Konya Province Example
No full textOne of the most important problems of our country, which is in an earthquake zone, is the low quality of the buildings and the weak earthquake resistance of the existing building stock. The main reason is that architectural and engineering services are not fully utilized during the construction phase and the building inspection system does not work properly. The loss of life and property in the Marmara in 1999, the Van in 2012, the Elâzığ in 2020, the Kahramanmaraş in 2023 and other earthquakes reveal how important building inspection is. This study aims to determine the effects of the changes in our country's building inspection system on building quality. In this context, the concept of building inspection and the historical development of building inspection were evaluated and building inspection practices were examined abroad. As a result of the literature review, it was seen that the scientific studies conducted in 2019 and before were prepared before the amendment made in the Law; the biggest problem identified in the studies was determined as the economic relations between the building owner/building contractors and building inspection organizations. This problem was largely solved with the amendment made to the Law. This thesis aims to evaluate the effect of the building inspection system, which gained a new application form with the radical changes made in 2019, on building quality compared to the previous period. In this direction, to determine the positive and negative aspects of the changes made in the legislation, a survey was conducted with participants consisting of building inspection organization partners, inspection personnel, contractors, construction site managers, relevant administration and Provincial Directorate personnel operating in Konya Province. In the light of the examination of the changes made in the legislation and the data obtained from the survey results; It has been concluded that all changes made in the Law and Secondary Legislation in 2019, especially the distribution of work in the electronic environment, the electronic concrete monitoring system and the classification of building contractors, have made significant contributions to the quality of inspection and building quality compared to the period before 2019, that the deficiencies in the legislation were tried to be eliminated with the changes made. Still, the weaknesses experienced in practice could not be fully eliminated, and the purpose of the Law could not be fully achieved. It is recommended that the public be made aware that no building can be built without being subject to the building inspection system and inspection, that in-service training be provided to increase the professional knowledge and experience of those responsible for building inspection, that public officials be in the field more and conduct more effective inspections to improve the quality of inspections, building quality be increased by activating project and inspection activities with digitalization and artificial intelligence.Deprem kuşağında yer alan ülkemizin en önemli sorunlarından biri yapı kalitesinin düşük olması ve mevcut yapı stokunun depreme karşı dayanımının zayıf olmasıdır. Bunun başlıca nedeni yapı üretimi aşamasında, mimarlık ve mühendislik hizmetlerinden tam anlamıyla faydalanılmaması ve yapı denetim sisteminin sağlıklı çalışmamasıdır. 1999 yılında Marmara Depremi, 2012 yılında Van Depremi, 2020 yılında Elâzığ Depremi, 2023 yılında Kahramanmaraş Depremi ve diğer yaşanılan depremlerde oluşan can ve mal kaybı, yapı denetiminin ne denli önemli olduğunu ortaya koymaktadır. Bu çalışma ile ülkemizde uygulanmakta olan yapı denetim sisteminde yapılan değişikliklerin, yapı kalitesine etkilerinin tespit edilmesi amaçlanmıştır. Bu bağlamda yapı denetim kavramı ile yapı denetimin tarihsel gelişimi hakkında değerlendirmeler yapılarak, yurt dışında yapı denetim uygulamaları incelenmiştir. Literatür taraması sonucunda, 2019 yılı ve öncesinde yapılan bilimsel çalışmaların, Kanunda yapılan düzenlemeden önce hazırlanmış olduğu, çalışmalarda tespit edilen en büyük sorunun yapı sahibi / yapı müteahhitleri ile yapı denetim kuruluşları arasındaki ekonomik ilişkiler olarak belirlendiği, Kanunda yapılan düzenleme ile bu sorunun büyük ölçüde çözülmüş olduğu görülmüştür. Bu tez çalışması ile 2019 yılında yapılan köklü değişikliklerle yeni bir uygulama şekli kazanan yapı denetim sisteminin önceki döneme kıyasla yapı kalitesine etkisinin değerlendirilmesi hedeflenmiştir. Bu doğrultuda mevzuatta yapılan değişikliklerin olumlu ve olumsuz yönlerinin belirlenmesi amacıyla Konya İlinde faaliyet gösteren, yapı denetim kuruluşu ortakları, denetim elemanları, müteahhitler, şantiye şefleri, ilgili idare ve İl Müdürlüğü personelinden oluşan katılımcılara yönelik anket yapılmıştır. Mevzuatta yapılan değişikliklerin incelenmesi ve anket sonuçlarından elde edilen veriler ışığında; 2019 yılında Kanun ve İkincil mevzuatta yapılan değişikliklerden elektronik ortamda iş dağılımı, elektronik beton izleme sistemi ve yapı müteahhitlerinin sınıflandırılması başta olmak üzere yapılan bütün değişikliklerin 2019'dan önceki döneme kıyasla denetim kalitesine ve yapı kalitesine önemli katkıları olduğu, mevzuatta bulunan eksikliklerin yapılan değişikliklerle giderilmeye çalışıldığı, ancak uygulamada yaşanılan eksikliklerin tam anlamıyla giderilemediği, Kanunun amacına tam anlamıyla ulaşılamadığı sonucuna varılmıştır. Yapı denetim sistemine ve denetime tabi olmadan hiçbir yapı yapılamayacağı hususunda halkın bilinçlendirilmesi, yapı denetimde görevi bulunanların mesleki bilgi ve tecrübelerinin artırılmasına yönelik hizmet içi eğitim verilmesi, denetim kalitesinin artırılması için kamu görevlilerinin de daha fazla sahada olması ve etkin denetim yapması, dijitalleşme ve yapay zekâ ile proje ve denetim faaliyetlerinin etkinleştirilerek yapı kalitesinin artırılması önerilmektedir
Bir Endüstriyel Robotun Dinamik Engellerden Kaçınması için Optimum Zaman-Sarsım Yörünge Planlaması
No full textIn this study, the optimal time-jerk trajectory planning for dynamic obstacle avoidance of an industrial robot is investigated. Nowadays, studies are raising to reduce the execution time in operation as well as energy consumption, payload stability and positioning accuracy. Firstly, the Denavit-Hartenberg method is used to determine the joint variables. Then forward and inverse kinematics calculations were determined from these variables. After that, the trajectory planning using the seventh polynomial is performed between the first and the goal point. While there are dynamic obstacles in the path of robot, the optimized polynomial recompute the trajectory between the current end effector position, goal position and the optimum point near the nearest dynamic obstacle that comes from the Adaptive elite genetics algorithm with the same execution time that is needed for accomplish the optimum path (original path).Secondly, Adaptive elite genetic algorithm optimization is designed for dynamic states where the optimum solution has to be found in one step related to the changeable environment .The performance of different number of obstacles and speeds for Adaptive elite genetic algorithm optimization and seventh polynomial optimization are presented with graphics. In all the different scenarios, the robot arm has successfully reached the goal point with optimized path, jerks and the same execution time while it is under the limited constraints.Bu çalışmada, bir endüstriyel robotun dinamik engelden kaçınması için optimum zaman-sarsım yörünge planlaması incelenmiştir. Günümüzde, operasyon süresini kısaltmanın yanı sıra enerji tüketimini, taşıma kararlılığını ve konumlandırma hassasiyetini artırmaya yönelik çalışmalar artmaktadır. İlk olarak, eklem değişkenlerini belirlemek için Denavit-Hartenberg yöntemi kullanılmıştır. Ardından, bu değişkenlerden ileri ve ters kinematik hesaplamaları yapılmıştır. Sonrasında, ilk ve hedef nokta arasında yedinci dereceden polinom kullanılarak yörünge planlaması gerçekleştirilmiştir. Robotun yolunda dinamik engeller bulunduğunda, optimize edilmiş polinom, mevcut uç efektör konumu, hedef konum ve en yakın dinamik engelin yakınındaki optimum nokta arasında, optimum yolun tamamlanması için gereken aynı yürütme süresiyle yörüngeyi yeniden hesaplamaktadır. Bu optimum nokta, Adaptif Elit Genetik Algoritma ile elde edilmektedir. İkinci olarak, Adaptif Elit Genetik Algoritma optimizasyonu, optimum çözümün değişken ortama bağlı olarak tek adımda bulunması gereken dinamik durumlar için tasarlanmıştır. Farklı engel sayıları ve hızları için Adaptif Elit Genetik Algoritma optimizasyonu ve yedinci dereceden polinom optimizasyonunun performansları grafiklerle sunulmuştur. Tüm farklı senaryolarda, robot kolu, sınırlı kısıtlar altında Optimize Edilmiş Yörünge, sarsım ve aynı yürütme süresiyle başarıyla hedef noktaya ulaşmıştır
Comprehensive Comparison of Deep Learning Architectures for Stroke Classification From CT Images
No full textIsik UniversityStroke, a leading cause of death and permanent disability worldwide, is classified into ischemic and hemorrhagic types. Accurate and timely classification from CT images is critical for effective treatment in emergency care. This study compares modern deep learning models ResNet, ViT, EfficientNet, Inception, ResNeXt, MobileNet, ConvNeXt, ConvNeXtV2, and DaViT - for classifying stroke (ischemic, hemorrhagic) and non-stroke cases from CT images. Models were evaluated using the 2021 Teknofest stroke dataset based on accuracy, precision, specificity, and computational efficiency. Results show that while advanced models like ViT and ConvNeXtV2 offer high performance, lightweight architectures such as MobileNet (F1-score: 97.59%) are clinically viable and ideal for resource-limited environments. © 2025 Elsevier B.V., All rights reserved
Towards Geodetic-Level Accuracy in Low-Cost GNSS: Tectonic Velocity Determination Capabilities of the U-Blox ZED-F9P Over a Year Multi-GNSS PPP-AR Time Series
No full textThe growing availability of low-cost dual-frequency GNSS receivers is enhancing their suitability for various kinds of geodetic applications. Geodetic monitoring of the continuous crustal deformation using GNSS time series analysis is one of the commonly used geodetic applications. To maintain the most accurate estimated parameters such as secular velocity, seasonal signal parameters and offsets, geodetic-grade GNSS receivers are commonly used in the GNSS time series analysis. However, due to the increasing availability of low-cost dual-frequency GNSS receivers and advancements in software and hardware, these receivers have now reached a level that supports the GNSS time series analysis. In this study, over a year of multi-GNSS PPP-AR time series of the u-blox ZED-F9P low-cost GNSS receiver are investigated by evaluating the accuracy of the estimated parameters, comparing them with data from a geodetic-grade GNSS receiver monumented on a building roof. The results show that the minimum detrended standard deviation obtained from White Noise (WN) estimation is achieved using GPS + GLONASS + Galileo PPP for both receivers. The computed annual velocity and amplitude differences obtained from the GNSS time series between the u-blox ZED-F9P and the geodetic-grade GNSS receivers using GPS + GLONASS + Galileo PPP-AR are found as 0.6 mm / 0.4 mm / 0.8 mm and 1.5 mm / 0.4 mm / 0.2 mm for north, east, and up components, respectively. © 2025 Elsevier B.V., All rights reserved
A Comprehensive Review on YOLO Versions for Object Detection
No full textThe need for methods used for object detection has gained increasing momentum in recent years. Starting with traditional image processing techniques, this process has been facilitated by the addition of deep learning. Object detection is currently used in areas such as autonomous vehicles, disease diagnosis, robotic vision and industry. The types of systems that are predicted to be needed more and more in the age of developing technology are also increasing. In particular, YOLO (You Only Look Once), which is mostly preferred in real-time object detection, is preferred because it achieves high accuracy in a short time. This paper analyses the main versions of the YOLO algorithm since its first release. The paper systematically analyses the architectural differences between the versions of the YOLO algorithm, the strengths and weaknesses of the models and their contribution to performance. At the same time, in most of the previous studies on YOLO, a comprehensive comparison of the YOLOv9-v11 models is not presented and new architectural features are not evaluated. This review provides an in-depth analysis of the main versions from YOLOv1 to YOLOv11, including recent innovations such as NMS-free, Oriented Bounding Boxes (OBB), GELAN and PGI. This work is intended to be a useful guide for researchers and developers interested in the field. © 2025 Elsevier B.V., All rights reserved
Prediction of Uniaxial Compressive Strength of Rocks by Non-Destructive Testing Via Different Machine Learning Algorithms
No full textUniaxial Compressive Strength (UCS) is a fundamental parameter in engineering projects, often serving as a primary input for various analyses. The direct determination of UCS requires laboratory sample preparation in accordance with established standards. However, in cases where sample extraction is unfeasible due to the rock type or field conditions, UCS must be estimated through indirect methods. Over the years, numerous rock properties such as porosity, density, P-wave velocity, and Schmidt hammer rebound value have been employed as predictor variables for UCS estimation. In this study, UCS was predicted using Schmidt hammer rebound (SHR) and Leeb hardness (HL), which are practical, cost-effective, and non-destructive testing methods. Various machine learning algorithms including Linear Regression, Ridge Regression, Lasso Regression, ElasticNet Regression, Random Forest, Gradient Boosting, and Support Vector Regression were applied for prediction. The correlation coefficient (R2) obtained from these models ranged between 0.75 and 1.00. Among the tested models, the Random Forest (RF) algorithm demonstrated the highest prediction accuracy, with validation metrics of RMSE = 1.93, MSE = 0.87, and R-2
Eco-Friendly Leaching of Metallic Silver With Boric Acid: Kinetics Study
No full textThis article discusses the kinetics of using a hydrogen peroxide solution to dissolve pure metallic silver in boric acid. The impact of temperature, rotation speed, hydrogen peroxide (H2O2) concentration, and boric acid concentration were investigated. The results indicate that silver dissolution rate and rotation speed have a positive relationship. Additionally, boric acid concentrations ranging from 0.10 to 0.40 M significantly enhance the dissolution process. The hydrogen peroxide concentration has no discernible influence on the rate of dissolution. While temperatures between 20 and 40 degrees C are beneficial, temperatures above 40 degrees C had the opposite effect and caused a layer of boron oxide (B2O3) to form. The activation energy was determined to be 30.49 kJ/mol
Kenevir Lifli Kompozit Malzemelerde Farklı Bağlayıcıların Isı, Nem, Yangın ve Ses Performansına Etkisi
No full textKenevirin sağladığı düşük yoğunluk, yüksek ısı yalıtım kapasitesi ve kenevirin hızlı büyümesi, biyolojik çeşitlilik, karbon tutma kapasitesi gibi çevre dostu özellikler, bu levhaların enerji verimliliğini artırırken, yapıların dayanıklılığını da desteklemektedir. Bu tez çalışması, bu levhaların potansiyel kullanım alanlarını, malzeme karışımındaki farklı oranların etkisini ve levhaların performansını incelemektedir. Yapılan bu çalışma, yapı sektöründe yenilikçi ve sürdürülebilir çözümler arayışına önemli bir katkı sağlanması hedeflenmektedir. Kenevir kıtığının yapı malzemesi olarak kullanımı, hem çevresel etkileri azaltma hem de enerji verimliliğini artırma potansiyeli taşımaktadır. Konya Teknik Üniversitesi Teknik Bilimler Meslek Yüksekokulu İnşaat Laboratuvarı'nda ham MDF malzemeden deney düzeneği oluşturulmuştur. Oluşturulan deney düzeneğinde 1. grup olarak %35, %25 ve %15 oranında ağırlıkça kenevir kıtığı, kil ve kireç karışımdan eni ve boyu 50 cm ölçülerinde 5 cm kalınlığında levhalar üretilmiştir. 2. Grup olarak %35, %25 ve % 15 oranında ağırlıkça kenevir kıtığı, kil, kireç ve çimento karışımından eni ve boyu 50 cm ölçülerinde 5 cm kalınlığında levhalar üretilmiştir. Üretilen bu levhalarla içten kaplanarak her bir malzeme için mevcut ortam sıcaklığı, 15, 20, 25, 30, 35 ve 40 °C sıcaklıklarda ve sabit sıcaklık için de 100, 125, 250, 500, 1000 ve 2000 Hz'de olmak üzere deneyler yapılmıştır. Isı ve ses deney sonuçları, ayrıca 6 farklı malzeme için tek noktadan yanma deneyi ve nem sonuçları kıyaslanmıştır. Yapılan deneyler sabit sıcaklıkta ses geçirimliliği ve ısı geçirimliliği en düşük %35 oranında kenevir kıtığı, kil ve kireç karışımlı levha olmuştur. Tek nokta yanma deneyinde ise yanma dayanımı en yüksek %15 oranında kenevir kıtığı, kil, kireç ve çimento olduğu sonucuna ulaşılmıştır. Nem oranı deneyinde ise nem oranının en yüksek olan levha %35 oranlı kenevir kıtığı, kil ve kireç karışımıdır.Hemp's low density and high thermal insulation capacity, along with its environmentally friendly properties such as rapid growth, biodiversity support, and carbon sequestration, contribute to improved energy efficiency and structural durability in building boards. This thesis explores the potential applications of these boards, the effects of varying material ratios, and their overall performance. The study aims to contribute significantly to the development of innovative and sustainable solutions in the construction industry. Using hemp shiv as a construction material has the potential to reduce environmental impacts while enhancing energy efficiency. An experimental setup was established using raw MDF at the Construction Laboratory of Konya Technical University, Technical Sciences Vocational School. In this setup, Group 1 boards were produced using 35%, 25%, and 15% hemp shiv, clay, and lime. Group 2 boards were made with the same hemp shiv ratios, but with the addition of cement to the mixture. All boards were produced with a width and height of 50 cm and a thickness of 5 cm. The boards were used for internal wall cladding. Experiments were conducted at ambient temperatures of 15, 20, 25, 30, 35, and 40°C. Additionally, tests were performed at fixed temperatures for frequencies of 100, 125, 250, 500, 1000, and 2000 Hz. Thermal and acoustic performance, single-point combustion resistance, and moisture content were evaluated across six different material types. Results showed that the board with 35% hemp shiv, clay, and lime had the lowest heat and sound transmission. The highest fire resistance was observed in the board containing 15% hemp shiv, clay, lime, and cement. The highest moisture content was found in the board with 35% hemp shiv, clay, and lime
Seismic Response Analysis of Different Soil Types With Equivalent Linear Analysis Method
No full textIn this study; With DEEPSOIL v7 software, seismic behavior analyzes of a region were made with 1D, "Equivalent Linear Analysis Method". The method that offers the closest solution to the reality in the solution of engineering problems is the nonlinear solution method. However, it is very difficult to obtain and analyze the necessary parameters. For this reason, this method was chosen, which is not difficult to solve and gives the closest results to the nonlinear solution. Analyzes were made in the direction of whether the soil profile will absorb the earthquake in the event of a possible earthquake or, on the contrary, will increase the earthquake effect and transmit it to the building foundation. As a result of the analysis, the peak acceleration values were calculated and defined with acceleration-time-depth graphs. In this study, in which the seismic responses of different types of soil structures were investigated, it was observed that the soil structure was non-linear, the shear wave velocity value was an important parameter in determining the dynamic behavior of the soil, and the damping ratio of the soil increased with the increase in the shear wave velocity value