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Characterization of Optical Aberrations Induced by Thermal Gradients and Vibrations via Zernike and Legendre Polynomials

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Optics and Photonics Journal 2016年第6期6卷 113-123页

作者： igor di Varano Leibniz Institut für Astrophysik Potsdam (AIP) Potsdam Germany

For every astronomical instrument, the operating conditions are undoubtedly different from those defined in a setup experiment. Besides environmental conditions, the drives, the electronic cabinets containing heaters and fans introduce disturbances that must be taken into account already in the preliminary design phase. Such disturbances can be identified as being mostly of two types: heat sources/sinks or cooling systems responsible for heat transfer via conduction, radiation, free and forced convection on one side and random and periodic vibrations on the other. For this reason, a key role already from the very beginning of the design process is played by integrated model merging the outcomes based on a Finite Element model from thermo-structural and modal analysis into the optical model to estimate the aberrations. The current paper presents the status of such model, capable of analyzing the deformed surfaces deriving from both thermo-structural and vibrational analyses and measuring their effect in terms of optical aberrations by fitting them by Zernike and Legendre polynomial fitting respectively for circular and rectangular apertures. The independent contribution of each aberration is satisfied by the orthogonality of the polynomials and mesh uniformity.

关键词： FEm Wavefront Error Zernike Legendre Polynomials Astronomical Instrumentation

Long Time Series Observations from Antarctica with the International Concordia Explorer Telescope （ICE-T）

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Journal of Physical Science and Application 2013年第1期3卷 33-37页

作者： igor di Varano Leibniz Institute for Astrophysics Potsdam (AIP) An der Sternwarte 16 Potsdam D-14482 Germany

The Intemational Concordia explorer telescope （ICE-T） is a f/1.1 Schmidt telescope, 61 cm aperture, with two optical tubes equipped with identical charged coupled devices 10.3× 10.3 k, 9μ pixel size, ultra-wide-fieldwith a total FOV of 65 square degrees. Its aim is to operate at Dome C, the French-Italian Antarctic Station, taking advantage of the long winter night for continuous observations. It is optimized for high precision photometry in two separate filters Sloan g and Sloan i ranging from 100 mmag to 10 mmag （from 9 to16 mag）. Among the scientific tasks there are the detection of hot Jupiters and Super Earths with the transit method, and related magnetic activity of the hosting stars. The 4m Radom dome for ICE-T together with 3 foundation pillars and the cables bundle have been already successfully installed in January 2009.

关键词： Instrumentation for astronomy antarctica design in extreme environment.

Pushing the limit of thermal conductivity of mAX borides and mABs

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Journal of materials Science & Technology 2022年第2期97卷 79-88页

作者： Shaohan Li Weiwei Sun Yi Luo Jin Yu Litao Sun Bao-Tian Wang Ji-Xuan Liu Guo-Jun Zhang igor di m.rco School of materials Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Province Key Laboratory of Advanced metallic materials Southeast UniversityNanjing 211189China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjing 210096China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China State Key Laboratory for modification of Chemical Fibers and Polymer materials College of Materials Science and EngineeringInstitute of Functional MaterialsDonghua UniversityShanghai 201620China Asia Pacific Center for Theoretical Physics PohangGyeonbuk 790-784Republic of Korea Department of Physics POSTECHPohangGyeonbuk 790-784Republic of Korea Department of Physics and Astronomy Uppsala UniversityBox 516Uppsala SE-75120Sweden

The emergence of mAX borides as well as mAB phases attracted great attention because of the renewable developments of ternary ceramics and offering great opportunities in potential ***,the number of borides remains limited,and further fundamental descriptions and detailed investigations on various properties are still *** this report,we employ an integrated computational scheme that combines density functional theory with the evolutional algorithm to search for the favorable structures of P-and S-glued ternary borides terminated by Nb *** discover that the structures of 212-type,as ***_(2)PB_(2)and Nb_(2)SB_(2),belong to the P6m2 space group,while those of 211-type,as ***_(2)PB and Nb_(2)SB,prefer to crystallize in the P6_(3)/mmc space group,and the corresponding carbides Nb_(2)PC and Nb_(2)SC are also considered for the sake of completeness and comparative *** predicted Nb_(2)PB_(2),Nb_(2)PB,Nb_(2)SB,Nb_(2)PC and Nb_(2)SC are energetically stable,as revealed by the negative formation energies and by the proposed reaction paths with respect to the most competing phases,as well as dynamically stable,as suggested by the non-imaginary phonon *** thermal conductivities of the six materials show unusual behaviors,particularly for the acoustic and optical contributions,and are accompanied by a strong *** importantly,Nb_(2)PB_(2) is found to be an excellent thermal conductor with a total thermal conductivity of~65 W/(m K),while Nb_(2)SC is found to be an ultra-low thermal conductor,with a total thermal conductivity of~5 W/(m K).These values are clearly outside the currently reported range of thermal conductivities,which makes Nb_(2)PB_(2)and Nb_(2)SC extremely interesting for fundamental research as well as prospective applications with the aid of artificial tunings on the almost independent mB block and the A *** discovery of these novel materials is expected to contribute substantially to the rapid deve

关键词： mAX and mAB phases Density functional theory calculation Structure searching Thermal conductivity

A Reverse Dynamical Investigation of the Catastrophic Wood-Snow Avalanche of 18 January 2017 at Rigopiano, Gran Sasso National Park, Italy

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International Journal of disaster Risk Science 2021年第1期12卷 40-55页

作者： Barbara Frigo Perry Bartelt Bernardino Chiaia igor Chiambretti margherita maggioni Department of Structural Building and Geotechnical Engineering-DISEGPolitecnico di Torino10129 TurinItaly WSL Institute for Snow and Avalanche Research SLF 7260 Davos DorfSwitzerland Associazione Interregionale di Coordinamento e documentazione per i problemi inerenti alla Neve e alle Valanghe–AINEVA 38122 TrentoItaly dipartimento di Scienze Agrarie Universita`di TorinoForestali e Alimentari–DISAFA10095 GrugliascoTOItaly Centro Interdipartimentale sui Rischi Naturali in Ambiente montano e Collinare–NatRisk 10095 GrugliascoTOItaly

On 18 January 2017 a catastrophic avalanche destroyed the Rigopiano Gran Sasso Resort&Wellness(Rigopiano Hotel)in the Gran Sasso National Park in Italy,with 40 people trapped and a death toll of *** article describes the location of the disaster and the general meteorological scenario,with field investigations to provide insight on the avalanche dynamics and its interaction with the hotel *** data gathered in situ suggest that the avalanche was a fluidized dry snow avalanche,which entrained a sligthtly warmer snow cover along the path and reached extremely long runout distances with braking effect from mountain *** avalanche that reached the Rigopiano area was a‘‘wood-snow’’avalanche—a mixture of snow and uprooted and crushed trees,rocks,and other *** were no direct eyewitnesses at the event,and a quick post-event survey used a numerical model to analyze the dynamics of the event to estimate the pressure,velocity,and direction of the natural flow and the causes for the destruction of the *** the magnitude and the damage caused by the event,the avalanche was at a high to very high intensity scale.

关键词： Avalanche flow velocity Avalanche impact pressure Forensic field investigation Italy Rigopiano disaster Wood-snow avalanche

Survival after surgery for acute type A aortic dissection in octogenarians

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Journal of Geriatric Cardiology 2024年第11期21卷 1015-1025页

作者： Antonio Fiore Javier Rodriguez Lega Joscha Buech Giovanni mariscalco Andrea Perrotti Konrad Wisniewski Angel G.Pinto Till Demal Jan Rocek Petr Kacer Giuseppe Gatti igor Vendramin mauro Rinaldi Eduard Quintana Dario di Perna Francesco Nappi mark Field Amer Harky matteo Pettinari Angelo m.Dell’Aquila Francesco Onorati mikko Jormalainen Tatu Juvonen Timo mäkikallio Caroline Radner Sven Peterss Vito D’Andrea Fausto Biancari Department of Cardiac Surgery Hôpitaux Universitaires Henri MondorCreteilFrance Cardiovascular Surgery Department University Hospital Gregorio MarañónMadridSpain LmU University Hospital Ludwig Maximilian UniversityMunichGermany German Centre for Cardiovascular Research Partner Site Munich Heart AllianceMunichGermany Department of Cardiac Surgery Glenfield HospitalLeicesterUnited Kingdom Department of Thoracic and Cardiovascular Surgery University of Franche-ComteBesanconFrance Department of Cardiothoracic Surgery University Hospital MuensterMuensterGermany Department of Cardiovascular Surgery University Heart and Vascular Center HamburgHamburgGermany Department of Cardiac Surgery Charles University and University Hospital Kralovske VinohradyPragueCzech Republic division of Cardiac Surgery Cardio-thoracic and Vascular DepartmentAzienda Sanitaria Universitaria Giuliano IsontinaTriesteItaly Cardiothoracic Department University HospitalUdineItaly Cardiac Surgery Molinette HospitalUniversity of TurinTurinItaly Department of Cardiovascular Surgery Hospital Clínic de BarcelonaUniversity of BarcelonaBarcelonaSpain Department of Cardiac Surgery Centre Hospitalier Annecy GenevoisEpagny Metz-TessyFrance Department of Cardiac Surgery Centre Cardiologique du Nord de Saint-DenisParisFrance Liverpool Centre for Cardiovascular Sciences Liverpool Heart and Chest HospitalLiverpoolUnited Kingdom Department of Cardiac Surgery Ziekenhuis Oost LimburgGenkBelgiumand Département CardiovasculairCliniques Universitaries Saint LucBruxellesBelgium Department of Cardiac surgery Martin Luther University Halle-WittenbergHalleGermany division of Cardiac Surgery University of Verona Medical SchoolVeronaItaly Faculty of medicine University of OuluOuluFinland Heart and Lung Center Helsinki University Central HospitalUniversity of HelsinkiHelsinkiFinland Department of medicine South-Karelia Central HospitalUniversity of HelsinkiLappeenrantaFinland Department of Surgical Sciences Sapienza Universi

Objective To evaluate the benefits of surgical repair acute type A aortic dissection(ATAAD)on survival of *** Patients who underwent surgery for acute ATAAD from the multicenter European Registry of Type A Aortic dissection(ERTAAD)were the subjects of the present *** 326(8.4%)patients were aged≥80 *** 280 propensity score matched pairs,in-hospital mortality was 30.0%in patients aged≥80 years and 20.0%in younger patients(P=0.006),while 10-year mortality were 93.2%and 48.0%,respectively(Pmortality was higher among octogenarians up to two years after surgery,but it became comparable to that of younger patients up to 5 *** patients who survived 3 months after surgery,10-year relative survival was 0.77 in patients agedmarkedly 5 years after ***≥85 years,glomerular filtration rate,preoperative invasive ventilation,preoperative mesenteric mal-perfusion and aortic root replacement were independent predictors of in-hospital mortality among octogenarians(AUC=0.792;E:O ratio=0.991;CITL=0.016;slope=1.096).An additive score was developed.A risk score≤1 was observed in 68.4%of patients,and their in-hospital mortality was 20.9%.Conclusions Provided a thoughtful patient selection,surgery may provide a survival benefit in patients aged≥80 years with ATAAD that,when compared to younger patients and the general population,may last up to 5 years after the *** findings have significant epidemiologic and clinical relevance because of the increasing longevity of the population of the Western countries.

关键词： surgery dissection Survival

Predicting Bank Interests When monetary Rates Are Close to Zero

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Applied mathematics 2016年第1期7卷 1-12页

作者： Laura Parisi igor Gianfrancesco Camillo Giliberto Paolo Giudici Department of Economics and management University of Pavia Pavia Italy Banco di Desio e della Brianza Risk Management Division Desio Italy Banca monte dei Paschi di Siena Siena Italy

monetary policies, either actual or perceived, cause changes in monetary interest rates. These changes impact the economy through financial institutions, which react to changes in the monetary rates with changes in their administered rates, on both deposits and lendings. The dynamics of administered bank interest rates in response to changes in money market rates is essential to examine the impact of monetary policies on the economy. Chong et al. (2006) proposed an error correction model to study such impact, using data previous to the recent financial crisis. In this paper we examine the validity of the model in the recent time period, characterized by very low monetary rates. The current state of close-to-zero monetary rates is of particular relevance, as it has never been studied before. Our main contribution is a novel, more parsimonious, model and a predictive performance assessment methodology, which allows comparing it with the error correction model.

关键词： Error Correction model Forecasting Bank Rates monte Carlo Predictions Interest Rate Risk models

Optical observations of LIGO source GW 170817 by the Antarctic Survey Telescopes at Dome A,Antarctica

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Science Bulletin 2017年第21期62卷 1433-1438页

作者： lei hu xuefeng wu igor andreoni michael c.b.ashley jeff cooke xiangqun cui fujia du zigao dai bozhong gu yi hu haiping lu xiaoyan li zhengyang li ensi liang liangduan liu bin ma zhaohui shang tianrui sun n.b.suntzeff charling tao syed a.uddin lifan wang xiaofeng wang haikun wen di xiao jin xu ji yang shihai yang xiangyan yuan hongyan zhou hui zhang jilin zhou zonghong zhu purple mountain observatory chinese academy of sciencesNanjing 210008China chinese center for antarctic astronomy Nanjing 210008China school of astronomy and space sciences university of science and technology of chinaHefei 230029China centre for astrophysics and supercomputing swinburne university of technologyHawthornVIC3122Australia the australian research council centre of excellence for gravitational wave discovery(ozgrav) Australia australian astronomical observatory north rydensw 2113Australia school of physics university of new south walesnsw 2052Australia the australian research council centre of excellence for all-sky astrophysics(caastro) Australia nanjing institute of astronomical optics and technology nanjing 210042China school of astronomy and space science and key laboratory of modern astronomy and astrophysics in ministry of education nanjing universitynanjing 210093China national astronomical observatories chinese academy of sciencesBeijing 100012China department of physics tianjin normal universitytianjin 300074china shanghai key laboratory for astrophysics shanghai normal universityshanghai 200234China george p.and cynthia woods mitchell institute for fundamental physics&astronomy texas a.&m.universitydepartment of physics and astronomy4242 tamucollege stationTX 77843USA aix marseille univ CNRS/N2P3CPPMmarseilleFrance physics department and tsinghua center for astrophysics(thca) tsinghua universityBeijing 100084China polar research institute of china shanghai 200136china department of astronomy beijing normal universitybeijing 100875china school of physics and technology wuhan universitywuhan 430072china

The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light.

关键词： Gravitational waves Binary neutron stars Gamma-ray bursts

The Russian‐Ukrainian armed conflict will push back the sustainable development goals

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Geography and Sustainability 2022年第3期3卷 277-287页

作者： Paulo Pereira Wenwu Zhao Lyudmyla Symochko miguel Inacio igor Bogunovic Damia Barcelo Environmental management Laboratory Mykolas Romeris UniversityVilniusLithuania Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Uzhhorod National University UzhhorodUkraine Institute of Agroecology and Environmental management NAAS KyivUkraine Faculty of Agriculture University of ZagrebZagrebCroatia Catalan Institute for Water Research(ICRA-CERCA) GironaCataloniaSpain

The Russian-Ukrainian armed conflict is a dramatic world event. Apart from the loss of life, the present conflicthas tremendous impacts on the environment, economy, and society. The conflict provoked a ripple of events withimplications at the global level, especially in energy and food. The escalation of this conflict is imposing severethreats to achieving the United Nations (UN) Sustainable Development Goals (SDGs) not only to the countries di-rectly involved in the conflict but also to other countries, especially the developing ones that are more vulnerableto the economic crisis. In this editorial, we assessed the impacts of the Russian-Ukrainian conflict on BiophysicalSDGs, Social SDGs, Economic SDGs and Partnership for the Goals SDG that consider all the previous *** Russian-Ukrainian conflict’s impact on the SDGs is variable. Biodiversity SDGs are mainly affected at theregional level (Russia, Ukraine, surrounding and European Union countries). Society SDGs are affected at local(e.g., SDG3 good health and wellbeing;SDG4 quality education) and global (e.g., SDG2 zero hunger) levels. Fi-nally, the Russian-Ukrainian armed conflict has world-level implications for the economic SDGs. Nevertheless,the ongoing conflict’s impacts are not entirely understood, and several uncertainties exist. Peace is needed toachieve the UN’s SDGs in 2030.

关键词： Russian-Ukrainian armed conflict Environment Society Economy Sustainable Development Goals(SDGs)

A new genus and two new species of Chrysomelinae(Coleoptera:Chrysomelidae) from China

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Entomotaxonomia 2012年第4期34卷 633-640页

作者：葛斯琴 DACCORdi mauro LOPATIN igor K. 崔俊芝李文柱杨星科中国科学院动物进化与系统学重点实验室中国科学院动物研究所 museo Civico di Storia Naturale Verona37129Italy Belarusian State University Minsk220030Belarus

A new leaf beetle genus Yulongedon gen. nov., and two new species, Y. formosus sp. nov. and Y. jambhalai sp. nov. from China, are described and illustrated here.

关键词： Chrysomelidae Chrysomelinae new genus new species China