5916 research outputs found
Sort by
Predicting the risky encounters without distance knowledge between the ships via machine learning algorithms
No full textAs the maritime traffic is getting denser, the number of encounters is increasing. The aim of this study is to develop a prediction model to classify encounters as risky or non-risky when two ships encounter in a certain buffer zone. A novel methodology is proposed to integrate three-dimensional clustering in the algorithm training process. K-means clustering, and ensemble machine learning algorithms-based prediction framework is developed to overcome class imbalance. The methodology is tested in the Strait of Istanbul (SOI) and parameters are generated from a long-term AIS dataset. Framework is validated via cross validation techniques. Precision, Recall, Accuracy and ROC-AUC Score are used as measures to evaluate models. Benchmark models are generated, and the most advanced model successfully predicts each 4 out of 5 risky encounters without the knowledge of distance between two ships. Eliminating distance from decision factors provides an action period before risky encounters. Therefore, proposed framework can be a guide for autonomous vessels for safe navigation and maritime authorities to improve maritime safety
Weighting factor-free model predictive control for three-level buck converters
No full textIn this paper, a Finite Control Set Model Predictive Control (FCS-MPC) algorithm is proposed. The cost function in this predictive control algorithm is designed to eliminate the dependency on the physical parameters of the circuit, which may have a high mismatch margin affecting the precision of the design. The algorithm is implemented for a three-level buck converter, and the simulation is compared to the classical FCS-MPC method. Compared to the classical MPC method, the proposed Lyapunov-based MPC method requires no gain tuning and has a simple design procedure while achieving comparable performance
Turkish children’s bedtime routines during the COVID-19 pandemic: preliminary evaluation of the bedtime routines questionnaire
No full textChildren’s routines, including bedtime, have been disrupted during the COVID-19 pandemic. How parents engage in their children’s bedtime routines has not yet been examined in Turkey. The purpose of the current study was to understand the nature of children’s bedtime routines and how these routines contributed to their sleep behaviors during the COVID-19 pandemic. Mothers of 313 (143 girls) children aged between 16 and 84 months old (M = 52.42, SD = 12.36) completed questionnaires regarding children’s bedtime routines and sleep behaviors. The structure of the bedtime routines questionnaire was confirmed. Results from the regression analyses showed that routine environment was related to both bedtime resistance and sleep duration. Reactivity during bedtime was related to bedtime resistance. Results highlight the importance of consistent bedtime routines for quality sleep
Search for higgs boson decay to a charm quark-antiquark pair in proton-proton collisions at √s=13 TeV
No full textA search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H → c c ¯ , produced in association with a leptonically decaying V ( W or Z ) boson is presented. The search is performed with proton-proton collisions at s = 13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb - 1 . Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z → c c ¯ in V Z events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ ( V H ) B ( H → c c ¯ ) is 0.94 ( 0.50 - 0.15 + 0.22 )pb at 95% confidence level (C.L.), corresponding to 14 ( 7.6 - 2.3 + 3.4 ) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ c , the observed (expected) 95% C.L. interval is 1.1 < | κ c | < 5.5 ( | κ c | < 3.4 ), the most stringent constraint to dateBMBWF 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); 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 (USA).Publisher versio
Legislative, institutional and political context
No full textRefugee governance has legislative, institutional, political, and discursive dimensions. These components co-constitute each other and reflect the fragments of strategic temporality as a building principal. It is possible to trace signs of strategic temporality in each dimension. This chapter starts with an overview of the legislative landscape marked by the Turkish asylum regime’s dual structure. Then, it maps the institutional architecture where relevant actors put these legislations into implementation. Both legislation and institutions play out in a highly political domestic and international context, which is scrutinised in the following section. The discursive dimension will be delved into further in Chap. 3.European Commissio
Is visible light communications suitable for using in lane-changing maneuvers?
No full textLane-changing behaviour is a crucial aspect of driving that requires a safe and efficient driving environment. To achieve this, an accurate perception of the surrounding vehicles and environment is essential, enabling the vehicle to make informed lane-changing decisions and ultimately improving the process's reliability and success rate. This paper uses a non-sequential ray channel modelling approach to investigate visible light communication (VLC) in lane change applications. The vehicle's headlamps and taillights act as wireless transmitters, while photo-detectors on other vehicles act as wireless receivers. The system performance is evaluated in terms of bit error rate (BER), spectral efficiency, and packet delivery ratio (PDR) for different inter-vehicle distances and lateral shifts. The effect of vehicle velocity on the system performance is also investigated. The results demonstrated that VLC could be qualified for exchanging data between the cars for a safe lane change. It also showed significant vehicle position and velocity impacts on the system performance during this process.Universitetet i Tromsø ; Interre
Metakaolin bazlı jeopolimer bağlayıcıların 3 boyutlu bastırılmaya uyarlanması için mikrodalga kür sistemi uygulaması
No full textThree-dimensional (3D) printing techniques of the construction materials such as contour crafting and additive manufacturing are being developed in the construction sector and replace the conventional building techniques used for generations. To achieve successful printing in large scale, it is necessary to develop advanced printing systems and compatible software. Another main challenge in 3D printing is to design a suitable material feasible with the requirements of the 3D printing in terms of its extrudability and buildability. It is also known that extrudability and buildability are also contradicting factors, as high workability causes more extrudability while the low workability provides more buildability. Therefore, the designed material should exhibit high level of workability as it is required to be extruded through the printer nozzle and sustain its shape without major deformation while subsequent layers are printed on top of each other. To obtain such structural reliability and applicability, fresh and hardened properties of the material such as tensile and compressive strength, static and dynamic yield stress obtained by rheological experiments, thixotropic behavior, flowability etc. should be evaluated. The goal of this study was to adapt metakaolin-based geopolymer mortar to 3D printing through a novel microwave curing approach. To achieve this goal, 3 types of precursor materials and 2 types of different curing regimes which are microwave and oven curing were utilized to enhance the materials' characteristic properties by triggering the rapid strengthening and buildability. The experimental design was established for samples with 3 different molar ratios (MR; 1.3,1.5 and 1.7) containing metakaolin, fly ash and silica fume. Samples were subjected to 3 different curing regimes: oven curing, microwave curing and hybrid curing (combination of optimized microwave and oven curing). Results showed that replacing a portion of applied oven curing with microwave curing in hybrid approach can increase operation speed and increase the rate of hardening. While the use of microwave curing in the geopolymer binders did not affect the alkali leaching, it increased the drying shrinkage in the material. Moreover, it was found that the samples can be hardened in 120 minutes once they are subjected to microwave curing while it was 60 minutes for hybrid curing. The use of microwave curing increased the green strength and dimensional stability without sacrificing from workability of the sample. Implementation of microwave curing improved the printability of metakaolin based geopolymers by affecting the buildability of the material. The outcomes of this study will pave a better design of set-on-demand geopolymer binders for advanced applications such as 3D printing by reducing the total duration of heat curing.İnşaat sektöründe "contour crafting" ve eklemeli üretim gibi yapı malzemelerini üç boyutlu (3D) yazdırma teknikleri geliştirilmekte ve nesiller boyu kullanılan geleneksel inşaat tekniklerinin yerini almaktadır. Büyük ölçekte başarılı prototip elde etmek için gelişmiş baskı sistemleri ve uyumlu yazılımlar geliştirmek gerekir. 3D baskıdaki bir diğer temel zorluk, 3D baskının ekstrüde edilebilirliği ve inşa edilebilirliği açısından gereksinimlerine uygun bir malzeme tasarlamaktır. Öte yandan, yüksek işlenebilirlik daha fazla ekstrüde edilebilirliğe neden olurken, düşük işlenebilirlik daha fazla inşa edilebilirlik sağladığından, ekstrüde edilebilirlik ve inşa edilebilirliğin de çelişen faktörler olduğu iyi bilinmektedir. Bu nedenle, tasarlanan malzemenin, yazıcı püskürtme ucundan ekstrüde edilmesi ve sonraki katmanların üst üste yazdırılırken büyük bir deformasyon olmadan şeklini koruması gerektiğinden yüksek düzeyde işlenebilirlik sergilemesi gerekir. Bu tür yapısal güvenilirlik ve uygulanabilirlik elde etmek için malzemenin çekme ve basınç dayanımı, reolojik deneylerle elde edilebilecek statik ve dinamik akma gerilmesi, tiksotropik davranış, akışkanlık vb. gibi taze ve sertleştirilmiş özellikleri değerlendirilmelidir. Bu çalışmanın amacı, metakaolin bazlı jeopolimer harcı yeni bir mikrodalga kürleme yaklaşımıyla 3D baskıya uyarlamaktı. Bu amaca ulaşmak için hızlı güçlendirme ve inşa edilebilirliği tetikleyerek malzemelerin karakteristik özelliklerini geliştirmek için 3 tip öncül malzeme ve 2 tip farklı kürleme rejimi; mikrodalga ve fırında kürleme yöntemleri kullanılmıştır. Deneysel tasarım; metakaolin, uçucu kül ve silika dumanı içeren 3 farklı molar oranına (MR; 1.3,1.5 ve 1.7) sahip numuneler için oluşturulmuştur. Numuneler 3 farklı kür rejimine tabi tutulmuştur: fırın kürü, mikrodalga kürü ve hibrit kür (optimize edilmiş mikrodalga ve fırın kürü kombinasyonu). Sonuçlar, uygulanan fırın kürlemesinin bir kısmının hibrit yaklaşımda mikrodalga kürleme ile değiştirilmesinin çalışma hızını ve sertleşme oranını artırabileceğini göstermiştir. Jeopolimer bağlayıcılarda mikrodalga kürleme kullanımı alkali özütlemeyi etkilemezken, malzemede kuruma rötresini arttırmıştır. Ayrıca, numunelerin mikrodalga küre tabi tutulduktan sonra 120 dakikada, hibrit kür için ise 60 dakikada sertleşebildiği tespit edilmiştir. Mikrodalga kürleme kullanımı, numunenin işlenebilirliğinden ödün vermeden yeşil dayanımı ve boyutsal stabiliteyi artırmıştır. Mikrodalga kürleme uygulaması, malzemenin inşa edilebilirliğini etkileyerek metakaolin bazlı jeopolimerlerin basılabilirliğini geliştirmiştir. Bu çalışmanın sonuçları, ısıl kürün toplam süresini azaltarak 3D baskı gibi ileri uygulamalar için isteğe bağlı jeopolimer bağlayıcıların daha iyi bir tasarımını sağlayacaktır
Local house price effects of internal migration in queensland: Australia's interstate migration capital
No full textWe examine the causal impact of internal migration on housing prices across 82 Statistical Areas Level 3 regions in Queensland, Australia from 2014–2019. The primary findings are: (i) an annual increase in the inflow of migrants equal to 1 per cent of a region's initial population leads to a 0.6 to 0.7 per cent annual increase in Queensland's house prices across different empirical specifications; (ii) this effect differs between the Greater Brisbane metropolitan area and Rest of State areas; (iii) migration from New South Wales fails to produce a significant influence on house price growth in Queensland
Search for long-lived particles using out-of-time trackless jets in proton-proton collisions at √s = 13 TeV
No full textA search for long-lived particles decaying in the outer regions of the CMS silicon tracker or in the calorimeters is presented. The search is based on a data sample of proton-proton collisions at root s = 13TeV recorded with the CMS detector at the LHC in 2016-2018, corresponding to an integrated luminosity of 138 fb(-1). A novel technique, using nearly trackless and out-of-time jet information combined in a deep neural network discriminator, is employed to identify decays of long-lived particles. The results are interpreted in a simplified model of chargino-neutralino production, where the neutralino is the next-to-lightest supersymmetric particle, is long-lived, and decays to a gravitino and either a Higgs or Z boson. This search is most sensitive to neutralino proper decay lengths of approximately 0.5 m, for which masses up to 1.18TeV are excluded at 95% confidence level. The current search is the best result to date in the mass range from the kinematic limit imposed by the Higgs boson mass up to 1.8TeV.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); BMBF, DFG, and HGF (Germany); GSRI (Greece); NK-FIH (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, 884104, and COST Action CA16108 (European Union); the Leventis Foundation; the Alfred P. Sloan Foundation; the Alexander von Humboldt Foundation; 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; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Hellenic Foundation for Research and Innovation (HFRI), Project Number 2288 (Greece); the Deutsche Forschungsgemeinschaft (DFG), under Germany's Excellence Strategy - EXC 2121 "Quantum Universe" - 390833306, and under project number 400140256 - GRK2497; 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; 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 B05F650021 (Thailand); the Kavli Foundation; the Nvidia Corporation; the SuperMicro Corporation; the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.).Publisher versio
Joint or decoupled optimization: Multi-UAV path planning for search and rescue
No full textIn this paper, we focus on path planning of drone teams deployed for search and rescue missions. The goal of the mission is to detect a target, inform the rescue personnel at the ground base station (BS), and form a communication relay chain between the target and the BS as fast as possible. Such missions where both detection and connectivity requirements need to be met can be planned by formulating (i) a single objective optimization problem with connectivity constraints; (ii) a multi-objective optimization problem where mission and connectivity needs are jointly optimized or (iii) mission and connectivity tasks are optimized decoupled from each other. Both joint and decoupled approaches have merit in terms of mission times, connectivity, cost and/or implementation. In this paper, we compare selected joint and decoupled multi-drone path planning approaches from mission and connectivity perspectives. We illustrate the trade-off between performance metrics from both viewpoints and show that depending on the available resources (e.g., number of drones) and the search area most suitable planner can change. We then propose a hybrid planner that utilizes joint optimization for the search drones and decoupled optimization for the relay drones. Hence, the proposed scheme has a flexibility due to allowing different search path planners to be used and a connectivity-wise better pre-mission plan. Our analysis shows that the hybrid scheme results in a better connectivity and total mission time if there are enough drones, but for very small number of search drones, hybrid scheme leads to a higher mission time than the joint scheme due to reservation of drones for relaying purposes.TÜBİTA