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Search for Resonant and Nonresonant Production of Pairs of Dijet Resonances in Proton-Proton Collisions at √s = 13 TeV (Vol 2023, 161, 2023)
No full textHall, Geoffrey/0000-0002-6299-8385; Gritsan, Andrei/0000-0002-3545-7970; Tapper, Alexander/0000-0003-4543-864
Effect of Stirrup Spacing on Strengthening Beams With Insufficient Shear Capacity Using Innovative Mechanical Steel Stitches
No full textThis study investigates experimentally and analytically the effect of stirrup spacing variation on the behavior of reinforced beams in the 45 degrees-inclined innovative mechanical steel stitches (MSSs) application for the strengthening of reinforced concrete beams with insufficient shear capacity. Within the scope of the experimental study, four-point loading tests were carried out under vertical loads by selecting stirrup spacing (250, 350, and 450 mm) and MSS spacing (d/3, d/2.5, d/2, d/1.7, and d/1.4) as variable parameters (d is effective depth of beam). In this context, a total of 12 beam specimens with dimensions of 125 x 250 x 2500 mm each with 250 and 450 mm stirrup spacing were produced, one reference specimen with each stirrup spacing and specimens reinforced with five different MSS spacings were tested; in addition, the test results of a reference beam with 350 mm stirrup spacing and beams reinforced with six different MSS spacings in the literature were used for comparison. Within the scope of the analytical study, the MSS spacing required for the beams to reach the flexural capacity was investigated by selecting the ratio of tensile reinforcement and the presence/absence of compressive reinforcement as variable parameters. In the study, the changes in failure mode, strength, ductility, stiffness, and energy consumption capacities of beams due to different stirrup and MSS spacings were analyzed. According to the experimental results obtained at the end of the study, it was observed that the reference beam with 250 mm stirrup spacing carried 32% and 35% more load than the reference beams with 350 and 450 mm spacing, respectively. Tightening the MSS up to 75 mm increased the shear capacity of beams with 450, 350, and 250 mm stirrup spacing up to 46.1%, 37.4%, and 23.5%, respectively. As the stirrup spacing of the reinforced beams decreased, the contribution of the MSS application to the shear capacity decreased. In addition, the failure mode of the beams changed from diagonal tension mode to splitting mode by increasing the MSS spacing. According to the analytical results, it was observed that MSS contributed more to the flexural capacity in beams with low longitudinal reinforcement ratio, and the performance of MSS was significantly improved in the absence of compression reinforcement.Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [122M091]Turkiye Bilimsel ve Teknolojik Arastirma Kurumu, Grant/Award Number: 122M09
Ogee Tipi Yan Savakların Savak Kapasitesinin Deneysel Olarak İncelenmesi
No full textSide weirs are structures placed parallel to the main channel or at certain angles in order to discharge excess water through side channels to prevent floods in the channels, to direct a certain amount of water to another place, and to control the level and flow rate of water in the main channels. Ogee type weir structures are among the most important parts of the accumulation structures. Weir structures are necessary to ensure the safety of the structure in case of any possible flood and to transfer the flood waters in a controlled or uncontrolled manner. In this study, it is aimed to experimentally investigate the sluice capacity of Ogee type weirs used as spillways in order to ensure the safety of the accumulation structures when they are used as side weirs. In addition, a flow coefficient equation was obtained for the side weir with Ogee profile and the validity of the equation was examined by comparing the values calculated as a result of this equation with the measurement results. According to the obtained results, it was seen that Ogee type side weirs have a better sluice performance compared to sharp-crested weirs and the calculation of the sluice flows with the obtained weir coefficient gave quite reliable results.Yan savaklar, kanallardaki taşkınların önüne geçebilmek amacıyla fazla suyun yan kanallarla deşarj edilmesi, suyun belli bir miktarının başka bir yere yönlendirilmesi, ana kanallardaki suyun seviyesinin ve debinin kontrol edilmesi amacıyla ana kanala paralel veya belirli açılarla yerleştirilen yapılardır. Ogee tipi savak yapıları biriktirme yapılarının en önemli kısımları arasındadır. Herhangi bir olası taşkın durumunda yapının güvenliğini sağlamak, taşkın sularını kontrollü veya kontrolsüz bir şekilde aktarabilmek için savak yapıları gereklidir. Bu çalışmada biriktirme yapılarının güvenliğini sağlamak için dolusavak olarak kullanılan Ogee tipi savakların yan savak olarak kullanılması durumunda savaklama kapasitesinin deneysel olarak araştırılması amaçlanmıştır. Ayrıca Ogee profiline sahip yan savak için bir debi katsayısı denklemi elde edilmiş ve bu denklem sonucunda hesaplanan değerler ile ölçüm sonuçları karşılaştırılarak denklemin geçerliliği irdelenmiştir. Elde edilen sonuçlara göre Ogee tipi yan savakların keskin kenarlı savaklara göre daha iyi bir savaklama performansına sahip olduğu ve elde edilen savak katsayısı ile savaklanan debilerin hesabının oldukça güvenilir sonuçlar verdiği görülmüştür
Determination of Solid Particle Erosion Wear Behaviour of Aircraft Turbine Blades Specific To Additive Manufacturing Orientation Effects
No full textIn many areas of the industry, especially in the aviation sector, mechanical components have to work under harsh environmental conditions. In addition to being exposed to extreme environmental conditions due to the environment in which they operate, the basic components of aircraft have to take into account many engineering details such as high strength expectations, speed and impact problems under the influence of hard particles. In addition, the geometries of parts in aircraft can be quite complex and detailed shapes. For this reason, it makes sense to utilize different manufacturing processes to create the final shapes of the components. In this study, a research was carried out to determine the solid particle erosion wear behaviour of In718 test specimens representing the material properties of jet engine turbine blades in aircraft by alternative manufacturing methods and to interpret the results obtained by performing experiments. In718 alloys with horizontal (0°), vertical (90°) and angular (45°) orientation were produced by selective laser melting, a layered powder-based additive manufacturing method, and test specimens were produced by casting, a conventional method. These specimens were subjected to solid particle erosion tests using three different sizes (500 g, 1000 g and 1500 g) of Al2O3 abrasive particles at 30° impact angle. Surface topography and macroscope images were used to interpret the results of the surface differences obtained at the end of the experiments. Consequently, the layer orientation in additive manufacturing and the additive manufacturing method were compared with parts produced by a conventional method in terms of erosion rate. In addition, it was concluded whether the surface damage that occurs in erosive wear depending on the impact angle has a ductile, semi-ductile or brittle character
Evaluation of Cadastre Update Studies
No full textCadastre is a system established to determine the ownership rights, boundaries, and land use status of a country's territories. Within this system, parcels and titleholders are produced. This production process is carried out by the General Directorate of Land Registry and Cadastre (TKGM). During this production process carried out by TKGM, cadastral maps have been produced using various measurement methods and different coordinate systems, as required by various regulations that have changed over time. The loss of currency of these maps over time, deformations caused by the materials used for the map bases, and their storage conditions negatively affect the technical accuracy that cadastral maps have or should have. Additionally, errors in the land registry records stemming from cadastral work and the failure to complete procedures for the determination of ownership rights lead to both legal and technical issues, resulting in cadastral maps containing insufficient or incomplete information. To address these problems, Law No. 2859 on the Renewal of Land Registration and Cadastre Maps was enacted, and technical correction procedures were carried out on the cadastral maps. However, these corrections remained limited and shallow, merely updating the maps without going beyond that. Amendments were made to Article 22 of the Cadastre Law No. 3402, which prohibited second cadastres, thereby introducing flexibility and allowing for the concepts of cadastre renewal or, in other words, renewal cadastre. While legal issues were also addressed through renewal cadastre, its application remained partial. To ensure a more integrated and comprehensive approach, the concept of cadastre updating was introduced, along with the Cadastre Updating Regulation, and in line with this, TKGM issued the 2018/13 (1792) Circular on the Implementation of Cadastre Updating Activities. With this circular, the scope and content of cadastre updating activities were expanded, making it possible to carry out procedures such as forest cadastre, registration of unregistered lands, inheritance transfers, subdivision, etc. In this study, the 2018/13 Circular on the Implementation of Cadastre Updating Activities is evaluated both in terms of its regulatory content and practical applicability. Moreover, a specific case study area is analyzed to examine the cadastre updating works carried out there. The chosen case study area is the İnler neighborhood in the Polatlı district of Ankara province. Cadastre updating works in this area were conducted between 2021 and 2022. Following these works, due to a decrease in the area of some cadastral parcels, compensation lawsuits were filed. During the ongoing legal proceedings, TKGM instructed the Cadastre Directorate to partially carry out a second round of cadastre updating, which commenced in 2024. This study also includes evaluations regarding the second round of cadastre updating. The study highlights deficiencies in the current regulations and proposes recommendations. It also presents a methodology for implementation and the need for legal amendments to address the issues encountered during the process and resolve the severe legal problems arising from changes in land area.Kadastro, bir ülkenin arazilerinin mülkiyet haklarını, sınırlarını ve kullanım durumunu belirlemek amacıyla oluşturulan bir sistemdir. Bu sistem içerisinde parsel ve malik üretilmektedir. Bu üretim ise Tapu ve Kadastro Genel Müdürlüğü tarafından yürütülmektedir. TKGM tarafından yürütülen bu üretim sürecinde; geçmişten günümüze kadar değişen farklı mevzuatlarda, değişik ölçü yöntemleri ile birbirinden farklı koordinat sistemlerinde kadastro paftaları üretilmiştir. Bu paftaların zaman içerisinde güncelliğini kaybetmesi, pafta altlıklarının materyallerinden ve saklanma koşullarından kaynaklı olan deformasyonlar; kadastro paftasının sahip olduğu ya da olması gereken teknik sıhhati bozmaktadır. Ayrıca kadastro çalışmalarından kaynaklı tapu sicilindeki hatalar ile mülkiyet hakkı tespitine yönelik işlemlerin tamamlanamaması; hem hukuki hem de teknik sorunlara yol açtığından, kadastro paftalarının yetersiz ve eksik bilgi barındırmasına neden olmaktadır. Bu sorunları gidermek adına 2859 Sayılı Tapulama ve Kadastro Paftalarının Yenilenmesi Hakkında Kanun çıkarılmış ve kadastro paftalarında teknik düzeltme işlemleri yapılmıştır. Bu düzeltmeler sadece pafta yenilemesi olmaktan öteye gidememiş sığ bir uygulama olarak kalmıştır. 3402 Sayılı Kadastro Kanununda değişiklikler yapılmış ikinci kadastroyu yasaklayan 22. maddesine esneklik getirilmiş kadastro yenileme ya da bir başka deyişle yenileme kadastrosu kavramları kullanılmaya başlanmıştır. Yenileme kadastrosu ile hukuksal sorunlara da girilmiş ancak bu çalışmada kısmi bir uygulama olarak kalmıştır. Daha bütünleşik ve geniş kapsamlı olması adına kadastro güncelleme kavramı ile kadastro güncelleme yönetmeliği oluşturulmuş ve buna bağlı olarak da TKGM tarafından 2018/13 (1792) sayılı Kadastro Güncelleme Çalışmaları Uygulama Genelgesini yayımlanmıştır. Bu genelge ile kadastro güncelleme çalışmalarının içerik ve kapsamı genişletilmiş; orman kadastrosu, tescil harici yerlerin tescili, intikal, ifraz vb. işlemler yapılabilir hale gelmiştir. Bu çalışmada; 2018/13 sayılı Kadastro Güncelleme Çalışmaları Uygulama Genelgesi, hem mevzuat içeriği olarak uygulanabilirlik açısından değerlendirilmiş hem de örnek bir uygulama sahası alınarak burada yapılan kadastro güncelleme çalışmaları irdelenmiştir. Örnek uygulama sahası olarak Ankara ili, Polatlı ilçesi, İnler mahallesi seçilmiştir. Bu uygulama sahasında kadastro güncelleme çalışmaları 2021-2022 yıllarında yapılmıştır. Bu çalışmalar sonrasında bazı kadastro parsellerinde meydana gelen yüzölçümü azalmasına bağlı olarak tazminat davaları açılmıştır. Devam eden hukuksal süreçler içerisinde de TKGM tarafından kısmi olarak ikinci kez kadastro güncelleme çalışmaları yapılmasına yönelik Kadastro Müdürlüğüne talimat verilmiş ve Kadastro Müdürlüğü tarafından kadastro güncelleme çalışmalarına 2024 yılında başlanılmıştır. Bu çalışmada, ikinci kez yapılan kadastro güncelleme çalışmaları hakkında da değerlendirmeler yapılmıştır. Mevzuatta noksan kalan işlemler ve bunlara yönelik önermeler, iş yapım sürecinde karşılaşılan sorunlar ile yüzölçümü değişikliğin getirmiş olduğu ağır hukuksal problemlerin çözümü adına uygulama metodolojisi ve mevzuat değişikliği ihtiyacı ortaya konulmuştur
Mukarnası Yeniden Değerlendirmek: Parametrik Üretken Bir Keşif
No full textMukarnas, İslam mimarisinin önemli bir unsuru olarak hem süsleme hem de yapısal işlevi ile portal, kubbe ve mihrab gibi elemanları süslemektedir. Mukarnas tasarımları genellikle projeksiyon planlarının oluşturulmasıyla başlayan inşa sürecini yönlendiren geometrik strüktürlere dayanmaktadır. Çalışma kapsamında İslami geometrik desenler ve ilk muqarnas prototiplerinden ilham alınarak mukarnas izdüşüm planları incelenmiş, kare ve baklava birimlerinden oluşan tessellasyonların ortaya çıktığı gözlenmiştir. Bu tessellasyonların geometrik yapısının analizi, sistematik bir yaklaşım geliştirilmesine olanak tanımaktadır. Rhinoceros programında Grasshopper eklentisi kullanılarak, her adım sistematik olarak işlenip mukarnas modelleri oluşturulmaktadır. Bu süreç, tessellasyonları üç boyutlu geometrik birimlere dönüştürerek mukarnas tasarımları olarak değerlendirmektedir. Mukarnas üretimleri sağlanmasının yanı sıra, geleneksel İslami geometrik desenler ile çağdaş hesaplamalı tasarım araçları arasında bir bağlantı ortaya koyan bu çalışma kültürel mirasın korunması ve yenilenmesine katkı sunmaktadır. Parametrik modeller, mukarnas tasarımında yer alan geometrik dönüşümlerin somut bir temsilini sağlayarak, İslam mimari tasarımında gelenekselliğin ve aynı zamanda yenilikçiliğin birleşimini yansıtmaktadır
A Novel Architecture for Artificial Neural Networks to Solve the Inverse Kinematics Problem in Robotics
No full textInverse kinematics calculations are of great importance to control robotic systems. In more specific applications such as vibration control and calculating endpoint forces, online inverse kinematics calculations are required, instantaneously. Geometric, iterative, and algebraic approaches might be insufficient to provide the desired speed or performance in complex robot structures such as a 6-degree-of-freedom industrial robot. Artificial neural networks (ANNs) are an appropriate alternative for pose prediction and trajectory generation to reduce computational cost. In the present study, cascade networks architecture is introduced. The novelty of this study is that the proposed architecture aims to reduce positioning errors by estimating each joint angle sequentially starting from the base considering the kinematic chain of the robot. The performance of ANNs for inverse kinematics prediction on precision was investigated. The proposed ANN architecture is compared with existing approaches. Neural networks are trained using the dataset obtained by forward kinematics calculations using the kinematic model of the Yaskawa GA50 industrial robot. Hyperparameters were systematically optimized through multiple observations. The optimized models to predict the solutions in joint space were evaluated for two different robotic trajectories. The proposed cascade neural network architecture improves the precision of the solutions
Recent Advances in Tracer-Aided Mixing Modeling of Water in the Critical Zone
No full textSafeguarding water resources for society and ecosystems requires a comprehensive understanding of hydrological fluxes within the Critical Zone, Earth's living skin where the atmosphere, hydrosphere, biosphere, and lithosphere meet. For decades, tracer-aided mixing models have been used to track water flow paths through the Critical Zone, mapping the journey of water particles from atmospheric moisture to groundwater. Recent advances in novel tracer measurements and modeling methodologies offer new insights into hydrological partitioning within the Critical Zone, enabling improved quantification of water fluxes across scales ranging from microscopic to macroscopic. Advanced tracer-aided modeling approaches enable more rigorous testing of assumptions and improved quantification of uncertainties. In this review, we (a) summarize state-of-the-art tracer and modeling techniques, with an emphasis on stable water isotope tracers, (b) synthesize insights emerging from new approaches, and (c) highlight opportunities to apply these methods in interdisciplinary Critical Zone research.This work has been part of the COST Action "WATSON"CA19120 (www.cost. eu). ALP acknowledges funding from the ISCOSCAN Water4All project. HB acknowledges funding from the ETH Zurich Postdoctoral Fellowship (#20-1 FEL-45). PA acknowledges funding from Research Council of Finland SNOMLT project (#347348). JG is funded by Deutsche Forschungsgemeinschaft (DFG, project no. 460817082). PV acknowledges funding from Slovenian Research and Innovation Agency (ARIS, program no. P1-0143). We also thank David Paul Genereux, Scott Jasechko, Michael Engel, Nuria Martinez Carreras, Hannu Marttila, Martin Sanda, Aurel Persoiu and Kazakis Nerantzis for early discussions and input to this review. ChatGPT was used to improve the grammar and readability of parts of this manuscript. We thank two anonymous reviewers for their comments, which improved this manuscript. Open access publishing facilitated by Eidgenossische Technische Hochschule Zurich, as part of the Wiley - Eidgenossische Technische Hochschule Zurich agreement via the Consortium Of Swiss Academic LibrariesSlovenian Research and Innovation Agenc
Multidisciplinary Insights Into Zeolite and Clay Formation in Hydrothermally Altered Volcanic Rocks of Çubuk, Turkey
No full textThe present study addressed the influence of lithological variability on hydrothermal alteration processes in the Çubuk region of Ankara, recognized globally for its agate occurrences. The objective was to clarify how differing host rocks, tuff and ignimbrite in Karadana, and perlitic units in Yukarlemirler, affect secondary mineral formation and alteration pathways. A combination of mineralogical (X-ray diffraction, Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy) and geochemical (energy-dispersive X-ray spectroscopy, whole-rock geochemistry, δ18O-δD) methods was utilized to characterize alteration assemblages and fluid conditions. The alteration sequence progressed through five stages, beginning with unaltered volcanic rocks. In the second stage, smectite-group clays, particularly montmorillonite, were formed under mildly alkaline and low-temperature conditions (pH 7.5-9.0; T 43-50°C). This initial clay formation was followed by zeolitization along two distinct pathways: clinoptilolite crystallized (K-rich, Si/Al ∼4.2) in the Karadana tuff-ignimbrite units, while heulandite formed (Ca-rich, Si/Al ∼2.7) in the perlitic host rocks of Yukarlemirler. These variations are attributed to differences in host-rock composition, permeability, and hydrothermal fluid chemistry. In more advanced stages, mordenite and chabazite precipitated under progressively higher pH and temperature conditions (pH 9.5-10.0; T 70-80°C). In the final stage, opal-quartz formed due to silica supersaturation triggered by a drop in pH, despite rising temperatures (pH ∼8.5-9.0; T ∼250°C). The paragenetic sequence confirms that clay mineral formation preceded zeolitization in both zones. Variations in zeolite types reflect strong lithological and hydrochemical controls, as well as the origin of the hydrothermal fluids; clinoptilolite formation in Karadana is associated with Na- and K-rich supergene fluids, while Ca-rich hypogene fluids promoted heulandite precipitation in Yukarlemirler. This study presents the first detailed paragenetic model for zeolite-clay alteration in the Çubuk volcanic system and offers new insights into post-caldera hydrothermal evolution in Central Anatolia. © 2025 Elsevier B.V., All rights reserved
Numerical Modeling of Photovoltaic Cells With the Meshless Global Radial Basis Function Collocation Method
No full textIspir, Murat/0000-0001-5238-6011Accurate prediction of photovoltaic performance hinges on resolving the electron density in the P-region and the hole density in the N-region. Motivated by this need, we present a comprehensive assessment of a meshless global radial basis function (RBF) collocation strategy for the steady current continuity equation, covering a one-dimensional two-region P-N junction and a two-dimensional single-region problem. The study employs Gaussian (GA) and generalized multiquadric (GMQ) bases, systematically varying shape parameter and node density, and presents a detailed performance analysis of the meshless method. Results map the accuracy-stability-computation-time landscape: GA achieves faster convergence but over a narrower stability window, whereas GMQ exhibits greater robustness to shape-parameter variation. We identify stability plateaus that preserve accuracy without severe ill-conditioning and quantify the runtime growth inherent to dense global collocation. A utopia-point multi-objective optimization balances error and computation time to yield practical node-count guidance; for the two-dimensional case with equal weighting, an optimum of 19 intervals per side emerges, largely insensitive to the RBF choice. Collectively, the results establish global RBF collocation as a meshless, accurate, and systematically optimizable alternative to conventional mesh-based solvers for high-fidelity carrier-density prediction in P-N junctions, thereby enabling more reliable performance analysis and design of photovoltaic devices