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Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryavtsev Yulia V.Sotnikova Vladislav A.Stolyarov Timur V.Mufakharov Valery V.Vlasyuk Margarita L.Khabibullina alexander G.Mikhailov Yulia V.Cherepkova Special Astrophysical Observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(hSP) blazars from the 3hSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of hSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

Next generation multiple access for IMT towards 2030 and beyond

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Science China(Information Sciences) 2024年第6期67卷 448-450页

作者： Zhiguo DING Robert SChOBER Pingzhi FAN h.Vincent POOR Department of Computer and Information Engineering Khalifa University Department of Electrical and Electronic Engineering University of Manchester Institute for Digital Communications Friedrich Alexander-University Erlangen-Nurnberg (FAU) CSNMT International Cooperation Research Center (MoST) Southwest Jiaotong University Department of Electrical and Computer Engineering Princeton University

Multiple access techniques are fundamental to the design of wireless communication systems,since many crucial components of such systems depend on the choice of the multiple access technique[1].For example,the use of ...

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Nonlinear Rydberg exciton-polaritons in Cu2O microcavities

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Light(Science & Applications) 2024年第4期13卷 619-627页

作者： Maxim Makhonin Anthonin Delphan Kok Wee Song Paul Walker Tommi Isoniemi Peter Claronino Konstantinos Orfanakis Sai Kiran Rajendran hamid Ohadi Julian heckötter Marc Assmann Manfred Bayer alexander Tartakovskii Maurice Skolnick Oleksandr Kyriienko Dmitry Krizhanovskii Department of Physics and Astronomy University of SheffieldSheffield S37RHUK. Department of Physics and Astronomy University of ExeterStocker RoadExeter EX44PYUK. SUPA School of Physics and AstronomyUniversity of St AndrewsSt Andrews KY169SSUK. Fakultät Physik TU DortmundAugust-Schmidt-Straße 444227 DortmundGermany

Rydberg excitons(analogues of Rydberg atoms in condensed matter systems)are highly excited bound electron-hole states with large Bohr *** interaction between them as well as exciton coupling to light may lead to strong optical nonlinearity,with applications in sensing and quantum information ***,we achieve strong effective photon–photon interactions(Kerr-like optical nonlinearity)via the Rydberg blockade phenomenon and the hybridisation of excitons and photons forming polaritons in a Cu2O-filled *** pulsed resonant excitation polariton resonance frequencies are renormalised due to the reduction of the photon-exciton coupling with increasing exciton *** analysis shows that the Rydberg blockade plays a major role in the experimentally observed scaling of the polariton nonlinearity coefficient as∝n4.4±1.8 for principal quantum numbers up to n=*** high principal quantum numbers studied in a polariton system for the first time are essential for realisation of high Rydberg optical nonlinearities,which paves the way towards quantum optical applications and fundamental studies of strongly correlated photonic(polaritonic)states in a solid state system.

关键词： density Rydberg polar

大国数字货币对小国宏观金融形势溢出效应研究

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新金融 2024年第7期 53-58页

作者： Anh h.Le alexander Copestake Brandon Tan Evan Papageorgiou SJay Peiris Umang Rawat 唐成千(译) 周正铭(译) 国际货币基金组织不详

央行数字货币(CBDC)快速发展,与传统法定货币不同,CBDC对宏观经济,尤其是对邻国的宏观经济有哪些影响值得关注。本文建立了一个考虑内生货币替代和金融摩擦的两国新凯恩斯模型,以考察大型外国经济体发行的稳定币对小型发展中经济体的影... 详细信息

央行数字货币(CBDC)快速发展,与传统法定货币不同,CBDC对宏观经济,尤其是对邻国的宏观经济有哪些影响值得关注。本文建立了一个考虑内生货币替代和金融摩擦的两国新凯恩斯模型,以考察大型外国经济体发行的稳定币对小型发展中经济体的影响。研究发现,外国稳定币为国内经济中的家庭提供流动性服务,并为国内通胀提供额外的对冲;同时,它的引入放大了货币替代效应,减少了银行中介作用,削弱了货币政策传导作用,加剧了衰退冲击的影响,增加了银行业经营压力;而资本管制提高了稳定币作为规避手段的使用率,增加了对外国冲击溢出效应的敞口。与国内中央银行数字货币不同,禁止外国稳定币支付可以缓解这些影响。本刊编译此篇国际货币基金组织(IMF)的工作论文,以期为读者带来启示。

关键词：央行数字货币(CBDC) 宏观金融形势溢出效应开放经济体金融摩擦

Pelvic fractures in blunt trauma patients:A comparative study

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World Journal of Orthopedics 2024年第5期15卷 418-434页

作者： alexander A Fokin Joanna Wycech Knight Madison E Tharp Kyler C Brinton Phoebe K Gallagher Justin Fengyuan Xie Russell D Weisz Ivan Puente Trauma and Critical Care Services Delray Medical CenterDelray BeachFL 33484United States Charles E Schmidt College of Medicine Department of SurgeryFlorida Atlantic UniversityBoca RatonFL 33431United States Trauma and Critical Care Services Broward Health Medical CenterFort LauderdaleFL 33316United States Charles E Schmidt College of Medicine Florida Atlantic UniversityBoca RatonFL 33431United States herbert Wertheim College of Medicine Department of SurgeryFlorida International UniversityMiamiFL 33199United States

BACKGROUND Pelvic fractures(PF)with concomitant injuries are on the rise due to an increase of high-energy *** of the elderly population with age related comorbidities further complicates the *** organ injuries are kindred with PF due to the proximity to pelvic *** of contrast blush(CB)on computed tomography in patients with PF is considered a sign of active bleeding,however,its clinical significance and association with outcomes is *** To analyze polytrauma patients with PF with a focus on the geriatric population,co-injuries and the value of contrast *** This retrospective cohort study included 558 patients with PF admitted to level 1 trauma center(01/2017-01/2023).Analyzed variables included:Age,sex,mechanism of injury(MOI),injury severity score(ISS),Glasgow coma scale(GCS),abbreviated injury scale(AIS),co-injuries,transfusion requirements,pelvic angiography,embolization,laparotomy,orthopedic pelvic surgery,intensive care unit and hospital lengths of stay,discharge disposition and *** study compared geriatric and non-geriatric patients,patients with and without CB and abdominal *** score matching was implemented in comparison *** PF comprised 4%of all trauma admissions.89 patients had CB.286(52%)patients had concomitant injuries including 93(17%)patients with abdominal *** patients compared to non-geriatric had more falls as MOI,lower ISS and AIS pelvis,higher GCS,less abdominal co-injuries,similar CB and angio-embolization rates,less orthopedic pelvic surgeries,shorter lengths of stay and higher *** propensity matching,orthopedic pelvic surgery rates remained lower(8%vs 19%,Phospital length of stay shorter,and mortality higher(13%vs 4%,Ph CB,45(51%)were *** propensity matching,patients with CB compared to without CB had more pelvic angiography(71%vs 12%,Phi

关键词： Pelvic fractures Geriatric trauma patients Abdominal co-injuries Contrast blush Contrast extravasation Angioembolization Polytrauma patients Surgical interventions Blunt trauma External and internal fixation for pelvic stabilization

Impact of T_(i)/T_(e )ratio on ion transport based on EAST h-mode plasmas

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Plasma Science and Technology 2024年第4期26卷 68-78页

作者：刘建文臧庆梁云峰陈佳乐邬潇河 alexander KNIEPS 扈嘉辉金仡飞张斌储宇奇刘海庆吕波段艳敏李妙辉陈颖杰龚先祖 the EAST Team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Forschungszentrum Jülich Gmbh Institut für Energie-und Klimaforschung-PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)Jülich 52425Germany

At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated h-mode plasmas. Nevertheless, recently it was found that the T_(i)/T_(e)ratio can increase further with the fraction of the neutral beam injection(NBI) power, which leads to a higher core ion temperature(Ti0). In NBI heating-dominant h-mode plasmas, the ion temperature gradient-driven modes become the most unstable ***, a strong and broad internal transport barrier(ITB) can form at the plasma core in high-power NBI-heated h-mode plasmas when the T_(i)/T_(e)ratio approaches ~1, which results in steep core Teand Tiprofiles, as well as a peaked neprofile. Power balance analysis shows a weaker Teprofile stiffness after the formation of ITBs in the core plasma region, where Ticlamping is broken,and the core Tican increase further above 2 keV, which is 80% higher than the value of Ticlamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of Ticlamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating.

关键词： ion temperature clamping transport neutral beam injection stiffness internal transport barrier

Characteristics of the SOL ion-to-electron temperature ratio on the J-TEXT tokamak with different plasma configurations

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Plasma Science and Technology 2024年第2期26卷 13-21页

作者：李存凯梁云峰江中和周松华建坤阳杰杨庆虎 alexander KNIEPS Philipp DREWS 徐鑫毛飞越谢伟杨雨桐郭金龙李杨波任正康陈志鹏王能超 the J-TEXT Team International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Forschungszentrum Jülich Gmbh Institut für Energie-und Klimaforschung—PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)Julich 52425Germany 不详

Accurate measurement of the average plasma parameters in the edge region,including the temperature and density of electrons and ions,is critical for understanding the characteristics of the scrape-off layer(SOL) and divertor plasma transport in magnetically confined fusion *** the J-TEXT tokamak,a multi-channel retarding field analyzer(RFA) probe has been developed to study average plasma parameters in the edge region under various poloidal divertor and island divertor *** edge radial profile of the ion-to-electron temperature ratio,τ_(i/e),has been determined,which gradually decreases as the SOL ion self-collisionality,v_(SOL)*,*** is broadly consistent with what has been observed previously from various tokamak ***,the comparison of experimental results under different configurations shows that in the poloidal divertor configuration,even under the same v_(SOL)*,τ_(i/e) in the SOL region becomes smaller as the distance from the X-point to the target plate *** the island divertor configuration,τ_(i/e) near the O-point is higher than that near the X-point at the same v_(SOL)*,and both are higher than those in the limiter *** results suggest that the magnetic configuration plays a critical role in the energy distributions between electrons and ions at the plasma boundary.

关键词： ion temperature island divertor poloidal divertor retarding field analyzer(RFA)probe

Leveraging Robust Artificial Intelligence for Mechatronic Product Development—A Literature Review

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International Journal of Intelligence Science 2024年第1期14卷 1-21页

作者： alexander Nüßgen René Degen Marcus Irmer Fabian Richter Cecilia Boström Margot Ruschitzka CAD CAM Center Cologne Institute of Automotive Engineering Cologne (IFK) Faculty of Automotive Systems and Production Cologne University of Applied Science Cologne Germany Division of Electricity Department of Electrical Engineering Uppsala University Uppsala Sweden

Mechatronic product development is a complex and multidisciplinary field that encompasses various domains, including, among others, mechanical engineering, electrical engineering, control theory and software engineering. The integration of artificial intelligence technologies is revolutionizing this domain, offering opportunities to enhance design processes, optimize performance, and leverage vast amounts of knowledge. however, human expertise remains essential in contextualizing information, considering trade-offs, and ensuring ethical and societal implications are taken into account. This paper therefore explores the existing literature regarding the application of artificial intelligence as a comprehensive database, decision support system, and modeling tool in mechatronic product development. It analyzes the benefits of artificial intelligence in enabling domain linking, replacing human expert knowledge, improving prediction quality, and enhancing intelligent control systems. For this purpose, a consideration of the V-cycle takes place, a standard in mechatronic product development. Along this, an initial assessment of the AI potential is shown and important categories of AI support are formed. This is followed by an examination of the literature with regard to these aspects. As a result, the integration of artificial intelligence in mechatronic product development opens new possibilities and transforms the way innovative mechatronic systems are conceived, designed, and deployed. however, the approaches are only taking place selectively, and a holistic view of the development processes and the potential for robust and context-sensitive artificial intelligence along them is still needed.

关键词： Artificial Intelligence Mechatronic Product Development Knowledge Management Data Analysis Optimization human Experts Decision-Making Processes V-Cycle

Prevalence of Dental Anomalies among Patients Who Report to the Komfo Anokye Teaching hospital’s Orthodontic Clinic

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Open Journal of Stomatology 2024年第2期14卷 103-117页

作者： Ama Agyeibea Amuasi Daniel K. Sabbah alexander Oti-Achempong Rahman N. Mamah The Department Child Oral health & Orthodontics School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana The Department of Oral & Maxillofacial Sciences School of Medicine and Dentistry College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana

BACKGROUND: Dental anomalies are variations from the established well-known general anatomy and morphology of the tooth as a result of disturbances during tooth formation. They can be developmental, congenital, or acquired and may be localized to a single tooth or involve systemic conditions. AIM: To evaluate the prevalence of dental anomalies in patients who report to the Komfo Anokye Teaching hospital (KATh) dental clinics. METhOD: A descriptive cross-sectional design was used with a sample size of 92 patients aged 18 or older, obtained through convenience sampling. Data analysis was performed using SPSS version 26.0. RESULTS: The study included 92 patients aged 18 to 72 years, with 47.8% males and 52.2% females. Dental anomalies were observed in 51.1% of participants, with a higher prevalence in females (55.3%). The most common anomalies were diastema (48.3%), impacted teeth (22.0%), dilaceration (11.9%), and peg-shaped lateral teeth (6.8%). CONCLUSION: This study highlights the importance of conducting thorough dental examinations to identify and address dental anomalies, which may have implications for treatment. Early detection and correction of these anomalies are crucial to prevent future complications.

关键词： Dental Anomalies Prevalence Impacted Teeth Dilaceration