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Searching for Adoption of Electric Vehicles To Our Modern Life: a Discrete Event Simulation Analysis
No full textConsidering a massive stride in improving decarbonization and eventually in reaching net zero emission goal, electrification has spread through all types of industries. Prominently, in the transportation sector, the shift from fossil fuel toward electric vehicles (EVs) has been intensely realized and the past several years have seen the proliferation of EVs on the roads. Although influx of EVs is a fact, the literature suffers to provide valuable insights related to full-scale adoption of EVs. This paper proposes a novel and comprehensive variant of charging infrastructure in which there are noncommercial, commercial, and contracted commercial EVs depending on the offered business model. EVs can request alternating current (AC) charging, direct current (DC) charging, and battery swapping, and these requests are fulfilled by fixed and mobile chargers. Having developed a discrete event simulation model of the problem at hand, we implement full factorial experimental design, through which impacts of several factors involving business model, service type, arrival rate of EVs, waiting threshold, and the number of mobile chargers are detected on critical measures ranging from queuing times to the rate and mean time of EVs exceeding waiting threshold and from total revenue to service rate and utilization rate of mobile chargers. Significant statistical findings along with possible explanations are discussed.The authors are indebted many thanks to three unanimous referees and editors for their constructive and helpful comments, which greatly increase the content and the quality of the paper
Cost Analysis and Site Selection for Reclaimed Water Injection To Enhance Coastal Aquifer Sustainability
No full textDogan, Selim/0000-0002-2281-4967Coastal aquifers are increasingly threatened by seawater intrusion (SWI) due to unsustainable groundwater extraction practices. This study highlights the significance of addressing SWI in coastal regions, particularly in Mugla province, Turkiye, through the innovative use of reclaimed water for groundwater recharge. We investigate the economic viability and technical feasibility of utilizing reclaimed water from selected wastewater treatment plants (WWTPs) for this purpose. The study evaluates necessary infrastructure upgrades and associated costs for the construction and operation of injection wells, along with a detailed analysis of reclaimed water volumes and compliance with injection standards. Employing a multi-criteria ArcGIS site selection approach, optimal well locations are identified based on key factors, including proximity to roads, residential areas, fault lines, WWTPs, coastlines, slope, and land cover. Our findings reveal that while the majority of the study area is unsuitable for injection wells, 6 % is rated as suitable and 1.2 % as highly suitable. The total investment required amounts to approximately 1.3 million for well construction, with estimated annual operational costs of $12.6 million. This study underscores the potential of reclaimed water as a sustainable solution for SWI management and provides a strategic framework for groundwater resource management in coastal areas. Future research should build upon this methodology by incorporating additional criteria and exploring diverse scenarios to enhance injection well site selection and operational efficiency
Kabuk Yoğunluğu Değişiminin Pıte (birincil Dolaylı Topografik Etki) Üzerindeki Etkisi
No full textJeoit belirleme çalışmalarında 1 santimetre doğruluklu jeoit modeli oluşturmak ana hedeftir. Bu hedefin en hızlı ve en pratik şekilde çözülmesi bazı mühendislik problemlerinin çözülmesini kolaylaştırmaktadır. Bu nedenle jeoit belirmek için kullanılan yöntemler gün geçtikçe geliştirilmektedir. Stokes-Helmert yaklaşımı klasik jeoit modelleme seçeneklerinden biridir. Sınır değer probleminin çözümünde topoğrafya dikkatli bir şekilde ele alınmaz ise istenen hedefe ulaşmaya engeldir. Stokes-Helmert yaklaşımının son aşamasında PITE’nin (Birincil Dolaylı Topoğrafik Etki) hesabıyla kesin jeoit yüksekliği elde edilmektedir. Yoğunluk değişimi, PITE’nin hesabında ve dolayısıyla, jeoit yüksekliklerinde anlamlı farklılığa neden olur. Bu farkı görmek için bir sayısal yükseklik modeli ve kabuk yoğunluğu modelinden yararlanmak yeterlidir. Topoğrafyayı ilgilendiren yerbilimleri çalışmalarında yoğunluk değeri genelde ortalama 2.67 gr/cm³ alınır. Ancak bu değer bazı bölgelerde %20’lere yaklaşan farklılık gösterir. Yoğunluk değişimindeki böyle bir oran PITE hesabından bulunan değerleri desimetre mertebesinde etkiler. Bu çalışmada yoğunluk değişiminin PITE üzerindeki etkisi incelenecektir. Bu sayede ülkemizde santimetre doğruluklu jeoit belirleme çalışmalarına önemli bir katkı sağlanacaktır. PITE değerleri hesap noktasının yüksekliğine ve yoğunluğuna bağlıdır. Sayısal uygulama sonucunda değişken yoğunluklu PITE değerleri -43 cm ile -1 cm arasında değişirken, sabit yoğunluk kullanıldığında bu değerler -39 cm ile -10 cm arasındadır.In geoid determination studies, the main goal is to create a geoid model with an accuracy of 1 centimeter. Solving this goal in the fastest and most practical way makes it easier to implement some engineering problems. For this reason, the methods used to determine the geoid are being developed day by day. The Stokes-Helmert approach is one of the classical geoid modeling options. If the topography is not handled carefully in the solution of the boundary value problem, it is an obstacle to achieving the desired goal. In the final stage of the StokesHelmert approach, the exact geoid height is obtained by calculating the PITE (Primary Indirect Topographic Effect). The density change causes a significant difference in the PITE's calculation and, therefore, in the geoid heights. To see this difference, it is enough to use the digital elevation model and the crustal density model. In geosciences studies related to topography, the density value is usually taken as an average of 2.67 g/cm3. However, this value varies in some regions, approaching 20%. Such a ratio, which can be observed in the density change, affects the values obtained from the PITE calculation at the decimetre level. In this study, the effect of density change on PITE will be examined. In this way, an important contribution will be made to the centimeter accuracy geoid determination studies in our country. The PITE values depend on the height and density of the calculation point. As a result of numerical application, the density change gives PITE values between -43 cm and -1 cm, while under constant density these values are between -39 cm and 39 cm
The Effect of Natural Resin Applied To Gypsum-Stabilized Rammed Earth Surface on Water Resistance
No full textEarth material has numerous advantageous aspects such as providing structural comfort conditions without the need for additional layers as in reinforced concrete, having low cost, using less energy in production and use, being recyclable, being harmless to human health and the environment, and being ecological. However, it also has negative aspects such as weak compressive strength, sensitivity to water, causing space loss with thick walls, requiring labor and time. Studies conducted at ITU since 1980 have contributed to the development of alker building material, which has improved in many aspects such as water resistance, compressive strength, and rapid production of earth building material. Additives incorporated into the content of the earth mixture have yielded positive results in increasing water resistance. The contribution of the coating to be applied to the surface of alker to the protection of the material against water remains a topic lacking in the literature. It is important for the material to be applied to the surface to be environmentally friendly and sustainable in order to improve the quality of sustainable earth building material. Natural resins increase biological resistance by reducing water intake on the applied surface thanks to their water-repellent properties. In the study, it was investigated whether the application of natural resin to the surface of gypsum-modified rammed earth, known to have high water resistance compared to adobe, would further affect its water resistance. The earth mixture prepared according to the alker recipe was compressed in 6 steel molds with dimensions of 15 cm x 15 cm x 15 cm. Water absorption tests were performed on 3 resin-coated and 3 resin-free alker samples. The results of the study indicate that the application of natural resin to the surface of gypsum-modified rammed earth reduces water absorption and increases resistance to water, while also preserving the natural appearance of the material by forming a transparent and permeable layer. It has been concluded that natural resin is an effective alternative for increasing water resistance of alker material.Toprak malzeme, betonarmedeki gibi ek katmanlara ihtiyaç duyulmadan yapısal konfor koşullarını sağlaması, maliyetinin düşük olması, üretiminde ve kullanımında daha az enerji kullanılması, geri dönüştürülebilir olması, insan sağlığına ve çevreye zararsız olması ve ekolojik olması gibi sayısız avantajlı yöne sahiptir. Buna karşılık basınç dayanımının zayıf olması, suya karşı duyarlı olması, kalın duvarların mekândan kayıplara yol açması, işçilik ve zaman istemesi gibi olumsuz yönlere sahiptir. 1980 yılından bu yana İTÜ'de gerçekleştirilen kapsamlı çalışmalar, kerpicin su dayanımı, basınç dayanımı ve hızlı üretim gibi çeşitli özelliklerini geliştirmiş ve bu süreçte alker yapı malzemesi önemli bir yenilik olarak ortaya çıkmıştır. Toprak karışımının içeriğine katılan kireç su dayanımını artırmada olumlu sonuçlar doğurmuştur. Alkerin yüzeyine uygulanacak kaplamanın, malzemenin suya karşı korunumuna katkısı literatürde eksik kalmış bir konudur. Sürdürülebilir olan toprak yapı malzemesinin niteliğini iyileştirmek için yüzeyine uygulanacak olan malzemenin çevre dostu sürdürülebilir bir malzeme olması önemlidir. Doğal reçineler su itici özelliği sayesinde uygulandığı yüzeyde su alımını azaltarak fiziksel dayanımı artırmaktadır. Çalışmada, geleneksel kerpice kıyasla su dayanımı yüksek olduğu bilinen alçı katkılı sıkıştırılmış toprağın yüzeyine uygulanacak doğal reçinenin su dayanımına etkisi incelenmiştir. Alker reçetesine uygun hazırlanan toprak karışımı 15 cm x 15 cm x 15 cm boyutlarında 6 adet çelik kalıp içerisinde sıkıştırılmıştır. 3 adet reçineli ve 3 adet reçinesiz alker numunenin su emme deneyi gerçekleştirilmiştir. Çalışmanın sonuçları, alçı katkılı sıkıştırılmış toprak yüzeyine doğal reçine uygulamasının malzemenin su emme miktarını azaltarak suya karşı dayanımını artırdığını ve aynı zamanda malzemenin doğal görünümünü koruyarak şeffaf ve geçirgen bir tabaka oluşturduğunu göstermektedir. Doğal reçinenin alker malzemesinin suya dayanımını artırmak için etkili bir alternatif olduğu sonucuna ulaşılmıştır
The Effects of I/Q Imbalance on Reconfigurable Intelligent Surface-Asissted Spatial Modulation Systems
No full textThe demand of wireless communication technology is increasing day by day, and this needs improving the transmission and channel capacity of communication signals. As a solution for this problem multiple-input multiple-output (MIMO) communication models offered in the improvement research. Nevertheless it has been observed that there are restrictions in data transmission because of the problems such as inter-channel interference in MIMO communication models. Improvement of spectrum and energy efficiency is tried to ensure with new generation spatial modulation (SM) and similar communication models, which are offered as a solution to this data limitation, but system performance is negatively affected from hardware errors that occur during the application of these models. In-phase (I)/quadrature-phase (Q) (I/Q) imbalance, which is a hardware error that seriously reduces performance, also reduces system quality. Reconfigurable intelligent surface (RIS) technology, which has recently become a very popular idea in the field of wireless communication, is thought that will become widespread in new generation communication systems. During the integration of RISs into future communication systems, the effects of I/Q imbalance should not be ignored and the disruptive effects caused by I/Q imbalance in RIS-assisted systems should be eliminated. Considering all these situations, in this study; the effects of I/Q imbalance caused by hardware impairments are examined on RIS-assisted SM and SSK communication models in various scenarios. These scenarios has been created on the simulation by considering the miscellaneousness situations such as determining the detection algorithms according to the I/Q imbalance parameters and estimating the reflection phases of RIS technology. The results show that the negative effects of I/Q imbalance should be considered in the design of communication models that use the SM/SSK technique. It has been observed that the use of RIS reduces the IQ imbalance effect in SM/SSK communication models, but error performance still needs to be improved.Kablosuz haberleşme teknolojisine talep günden güne artmakta ve bu durum haberleşme sinyallerinin iletim ve kanal kapasitesini iyileştirme zorunluluğunu beraberinde getirmektedir. Söz konusu iyileştirme araştırmalarında çözüm önerisi olarak sunulan çok-girişli çok-çıkışlı (multiple-input multiple-output, MIMO) haberleşme modellerinde ise kanallar arası girişim gibi problemler sebebiyle veri iletiminde kısıtlama olduğu görülmüştür. Bu veri kısıtlamasına çözüm olarak sunulan yeni nesil uzaysal modülasyon (spatial modulation, SM) ve türevi haberleşme modelleri ile spektrum ve enerji verimliliği artırılmaya çalışılmakta ancak bu modellerin uygulanması esnasında oluşan donanımsal hatalar nedeniyle sistem performansı olumsuz etkilenmektedir. Sinyal performansını ciddi şekilde düşüren donanımsal hatalardan eş-faz (in-phase, I)/ dik-faz (quadrature-phase, Q) (I/Q) dengesizliği de sistem kalitesini azaltmaktadır. Son zamanlarda kablosuz haberleşme alanında oldukça popüler bir fikir haline gelen uyarlanabilir akıllı yüzey (reconfigurable intelligent surface, RIS) teknolojisinin yakın zamanda yeni nesil haberleşme sistemlerinde yaygınlaşacağı düşünülmektedir. Geleceğin haberleşme sistemlerine RIS'lerin entegrasyonu esnasında I/Q dengesizliği etkilerinin göz ardı edilmemesi ve RIS-destekli sistemlerde I/Q dengesizliğinden kaynaklanan bozucu etkilerin ortadan kaldırılması gerekmektedir. Tüm bu durumlar göz önünde bulundurularak bu tez çalışmasında; çeşitli senaryolar üzerinde donanımsal uyumsuzluklardan kaynaklanan I/Q dengesizliğinin RIS-destekli SM ve uzay kaydırmalı anahtarlama (space shift keying, SSK) haberleşme modelleri üzerindeki etkileri incelenmiştir. Ele alınan senaryolar; sezim algoritmalarının I/Q dengesizliği parametrelerine göre belirlenmesi ve RIS teknolojisinin yansıma fazlarını tahmin etme durumlarına göre çok yönlü ele alınarak simülasyon üzerinde oluşturulmuştur. Elde edilen sonuçlar SM/SSK tekniği kullanılan haberleşme modellerinin tasarımında I/Q dengesizliğinin olumsuz etkilerinin dikkate alınması gerektiğini göstermiştir. RIS kullanımının SM/SSK haberleşme modellerinde I/Q dengesizliği etkisini azalttığı görülse de sistemin hata performansının iyileştirilmesine ihtiyaç duyulduğu görülmüştür
The Role of Architecture Documentaries in The Adoption of Contemporary Design Approaches in Mosque Architecture: A Research on Architecture Students
No full textIn the historical process, mosques have exhibited different architectural features depending on various factors such as culture, geography and construction techniques, and have generally been defined by elements such as domes and minarets. Although mosque architecture has maintained its characteristic features for many years, new design approaches emerged with the Republican Era. In mosque architecture, which has been reinterpreted from a contemporary perspective, elements such as domes and minarets have undergone formal changes and interior elements have been reconsidered. However, the traditional image of the mosque in the minds of the public has created a resistance to contemporary design approaches and modern mosque designs have become a current topic of discussion. This study was carried out to understand the role of architectural documentaries in the perceptual change regarding the adoption of contemporary approaches by determining the tendencies of individuals regarding mosque architecture. In the research conducted on architecture students, the documentary 'Sancaklar Mosque' broadcasted in TRT2's Eşik program was used. Following an experimental method, user perception was evaluated with questionnaires applied before and after screening the documentary.The results were analyzed with \"Dependent Groups t-test\" in SPSS and the statistical significance of the change in user perception was discussed. The findings of the study showed that architecture documentaries significantly changed architecture students' acceptance of contemporary mosque designsIn addition, after screening the documentary, it was determined that the perception that architectural elements such as dome and minaret can be included in mosque architecture in different forms was strengthened.The results obtained show that mass media can be used not only as a tool in architectural education, but also as a method for informing the society and adopting contemporary design approaches to mosques
Measurement of the Primary Lund Jet Plane Density in Proton-Proton Collisions at √s=13 Tev
No full textA measurement is presented of the primary Lund jet plane (LJP) density in inclusive jet production in proton-proton collisions. The analysis uses 138 fb(-1) of data collected by the CMS experiment at root s = 13TeV. The LJP, a representation of the phase space of emissions inside jets, is constructed using iterative jet declustering. The transverse momentum kT and the splitting angle Delta R of an emission relative to its emitter are measured at each step of the jet declustering process. The average density of emissions as function of ln( k(T)/GeV) and ln( R/Delta R) is measured for jets with distance parameters R = 0.4 or 0.8, transverse momentum p(T) > 700 GeV, and rapidity |y| 1.7. The jet substructure is measured using the charged-particle tracks of the jet. The measured distributions, unfolded to the level of stable charged particles, are compared with theoretical predictions from simulations and with perturbative quantum chromodynamics calculations. Due to the ability of the LJP to factorize physical effects, these measurements can be used to improve different aspects of the physics modeling in event generators.We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid and other centers for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC, the CMS detector, and the supporting computing infrastructure provided by the following funding agencies: SC (Armenia), BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES and BNSF (Bulgaria); CERN; CAS, MoST, and NSFC (China); MINCIENCIAS (Colombia); MSES and CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); MoER, ERC PUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); SRNSF (Georgia); BMBF, DFG, and HGF (Germany); GSRI (Greece); NKFIH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MES and NSC (Poland); FCT (Portugal); MESTD (Serbia); MCIN/AEI and PCTI (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); MHESI and NSTDA (Thailand); TUBITAK and TENMAK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.). Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract Nos. 675440, 724704, 752730, 758316, 765710, 824093, 101002207, and COST Action CA16108 (European Union); the Leventis Foundation; the Alfred P. Sloan Foundation; the Alexander von Humboldt Foundation; the Science Committee, project no. 22rl-037 (Armenia); the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the Excellence of Science - EOS - be.h project n. 30820817; the Beijing Municipal Science ; Technology Commission, No. Z191100007219010 and Fundamental Research Funds for the Central Universities (China); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Shota Rustaveli National Science Foundation, grant FR-22-985 (Georgia); the Deutsche Forschungsgemeinschaft (DFG), under Germany's Excellence Strategy - EXC 2121 Quantum Universe - 390833306, and under project number 400140256 - GRK2497; the Hellenic Foundation for Research and Innovation (HFRI), Project Number 2288 (Greece); the Hungarian Academy of Sciences, the New National Excellence Program - UNKP, the NKFIH research grants K 124845, K 124850, K 128713, K 128786, K 129058, K 131991, K 133046, K 138136, K 143460, K 143477, 2020-2.2.1-ED-2021-00181, and TKP2021-NKTA-64 (Hungary); the Council of Science and Industrial Research, India; ICSC - National Research Center for High Performance Computing, Big Data and Quantum Computing, funded by the EU NexGeneration program (Italy); the Latvian Council of Science; the Ministry of Education and Science, project no. 2022/WK/14, and the National Science Center, contracts Opus 2021/41/B/ST2/01369 and 2021/43/B/ST2/01552 (Poland); the Fundacao para a Ciencia e a Tecnologia, grant CEECIND/01334/2018 (Portugal); the National Priorities Research Program by Qatar National Research Fund; MCIN/AEI/10.13039/501100011033, ERDF a way of making Europe, and the Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu, grant MDM-2017-0765 and Programa Severo Ochoa del Principado de Asturias (Spain); the Chulalongkorn Academic into Its 2nd Century Project Advancement Project, and the National Science, Research and Innovation Fund via the Program Management Unit for Human Resources ; Institutional Development, Research and Innovation, grant B37G660013 (Thailand); the Kavli Foundation; the Nvidia Corporation; the SuperMicro Corporation; the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.).FWF (Austria); FNRS (Belgium); FWO (Belgium); CNPq (Brazil); CAPES (Brazil); FAPERJ (Brazil); FAPERGS (Brazil); FAPESP (Brazil); BNSF (Bulgaria); MoST (China); NSFC (China); CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); MoER (Estonia); ERDF (Estonia); Academy of Finland (Finland); MEC (Finland); CEA (France); CNRS/IN2P3 (France); BMBF (Germany); DFG (Germany); HGF (Germany); NKFIH (Hungary); DAE (India); DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF (Republic of Korea); MES (Latvia); MOE (Malaysia); UM (Malaysia); BUAP (Mexico); CONACYT (Mexico); UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); FCT (Portugal); MESTD (Serbia); PCTI (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); NSTDA (Thailand); TUBITAK (Turkey); NASU (Ukraine); NSF (USA); Marie-Curie program (European Union); European Research Council (European Union); Horizon 2020 Grant (European Union) [675440, 724704, 752730, 758316, 765710, 824093, 884104]; COST Action (European Union) [CA16108]; Leventis Foundation; Alfred P. Sloan Foundation; Alexander von Humboldt Foundation; Belgian Federal Science Policy Office; Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); FWO (Belgium) under the Excellence of Science - EOS - be.h project [30820817]; Beijing Municipal Science ; Technology Commission [Z191100007219010]; Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; Hellenic Foundation for Research and Innovation (HFRI) (Greece) [2288]; Deutsche Forschungsgemeinschaft (DFG) [EXC 2121, 390833306, 400140256 - GRK2497]; Hungarian Academy of Sciences (Hungary); Council of Science and Industrial Research, India; Latvian Council of Science; National Science Center (Poland) [Opus 2021/41/B/ST2/01369, 2021/43/B/ST2/01552]; National Priorities Research Program by Qatar National Research Fund; MCIN/AEI, ERDF a way of making Europe; Programa Severo Ochoa del Principado de Asturias (Spain); Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); National Science, Research and Innovation Fund via the Program Management Unit for Human Resources ; Institutional Development, Research and Innovation (Thailand) [B05F650021]; Kavli Foundation; Nvidia Corporation; SuperMicro Corporation; Welch Foundation [C-1845]; Weston Havens Foundation (USA); BMBWF (Austria); MES (Bulgaria); CERN; CAS (China); MINCIENCIAS (Colombia); MSES (Croatia); ERC PUT (Estonia); HIP (Finland); GSRI (Greece); MSIP (Republic of Korea); LAS (Lithuania); CINVESTAV (Mexico); LNS (Mexico); SEP (Mexico); MOS (Montenegro); MES (Poland); NSC (Poland); MCIN/AEI (Spain); MST (Taipei); MHESI (Thailand); TENMAK (Turkey); STFC (United Kingdom); DOE (USA); F.R.S.-FNRS (Belgium); New National Excellence Program - UNKP (Hungary); NKFIH (Hungary) [K 124845, K 124850, K 128713, K 128786, K 129058, K 131991, K 133046, K 138136, K 143460, K 143477, 2020-2.2.1-ED-2021-00181, TKP2021-NKTA-64]; Ministry of Education and Science [2022/WK/14]; Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu (Spain) [MDM-2017-0765
Machine Learning-Based Shear Strength Prediction of Exterior Rc Beam-Column Joints
No full textColumn-beam joints are of critical importance in cast-in-situ reinforced concrete structures. Under the effect of earthquake, no damage should occur in these regions that would disrupt the integrity of the load-carrying system of a structure. In particular, shear damage in this area is very critical. Exterior joints that are not fully confined by the beams are forced under the effect of more shear force during an earthquake. Therefore, it is very important that the shear capacity of these areas is sufficient. Although there are empirical approaches for the estimating of the shear capacity of these areas in the seismic codes, the development of software that can predict with high accuracy using more innovative methods is also very important in terms of structural engineering. With this motivation, this study has developed a new method that uses machine learning to predict the shear strength in exterior column-beam joints of RC structures. Firstly, 270 shear damaged exterior joint experimental data sets were collected from the existing literature. Then, the shear strength capacity was determined according to 14 different parameters related to cross-section and material properties using different machine learning (ML) methods such as Multiple Linear Regression (MLR), Decision Tree (DT), Random Forest (RF), Support Vector Regression (SVR), Bootstrap Aggregating (Bagging), Gradient Boosting Regression (GBR), Adaptive Boosting (AdaBoost) and Extreme Gradient Boosting (XGBoost). Among the algorithms used, the GBR model provided the most successful predictions, according to achieved R-squared (R2) value and MAE and RMSE error metrics calculating %95.45, 42.10 and 62.98, respectively. Furthermore, ML models have more predictive power than the conventional building and seismic code approaches given for the shear capacity of column-beam joints. © 2024, The Author(s), under exclusive licence to Springer Nature Switzerland AG
A User-Friendly Software Package for Modelling Gravimetric Geoid by the Classical Stokes-Helmert Method
No full textWith the progress in Global Navigation Satellite Systems (GNSS) technology, accurate geoid modelling has started to play an essential role in geodetic applications such as establishing height datum as a continuous surface model and related vertical control for infrastructure projects. Thus, numerous geoid modelling methods have been offered since 1990's, each of them has its own algorithm and approximation theories. Classical Stokes-Helmert is one of the most well-known methods all over the world by geodetic communities. However, a user-friendly software package of the method is not publicly accessible on the Internet. Therefore, a compact and user-friendly software package CSHSOFT is developed and presented for scholars in this field. A fractionated programming strategy has been treated to build individual components striving high accuracy and computational efficiency for geoid heights. Subsequently, the CSHSOFT is simply tested to construct a geoid model in the mountainous area in Auvergne test-bed where several geoid modelling techniques are implemented. Afterward, the new geoid model of the region is externally evaluated by GNSS-levelling data in terms of rigorous orthometric heights. The fitting statistics of 2.75 cm and 0.36 ppm in absolute and relative height differences fairly indicate that the CSHSOFT is a vigorous tool for gravimetric geoid modelling, and can be comfortably employed for geoscientific and technical studies.Konya Technical UniversityThe authors would like to express their sincere gratitude to the creators of the Generic Mapping Tools (GMT) software package, P. Wessel and S. Smith. The GMT software has played a significant role in generating the majority of the figures presented in the current paper. The authors also express their gratitude to Dr. Ismael Foroughi from York University in Canada for providing orthometric heights of GNSS-levelling benchmarks
Investigating the Impact of Urban Growth on Land Use Using Spatial Autocorrelation Methods in Konya/Türkiye
No full textLand use land cover (LULC) change, global environmental change, and sustainable change are frequently discussed topics in research at the moment. It is important to determine the historical LULC change process for effective environmental planning and the most appropriate use of land resources. This study analysed the spatial autocorrelation of the land use structure in Konya between 1990 and 2018. For this, Global and Local Moran's I indices based on land use data from 122 neighbourhoods and hot spot analysis (Getis-Ord Gi*) methods were applied to measure the spatial correlation of changes and to determine statistically significant hot and cold spatial clusters. According to the research results, the growth of urban areas has largely destroyed the most productive agricultural lands in the region. This change showed high spatial clustering both on an area and a proportional basis in the northern and southern parts of the city. On the other hand, the growth in the industrial area suppressed the pasture areas the most in the north-eastern region of the city, and this region showed high spatial clustering on both spatial and proportional scales.DAS:Data will be made available on request