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High-resolution precipitation variations in the Northeast Tibetan Plateau over the last 800 years documented by sediment cores of Qinghai Lake

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Chinese Science Bulletin 2003年第14期48卷 1451-1456页

作者： ZHANGJiaw. JINMing CHENFahu R.w.Battarbee A.CoG.Henderson CenterforAddEnvironmentandPaleoclimateResearch NationalLab.ofWesternChina'sEnvironmentalSystemLanzhouUniversityLanzhou730000China DesertandDesertificationLab. ColdandAridRegionsEnviron-mentalandEngineeringResearchInstituteChineseAcademyofSci-encesLanzhou730000China EnvironmentalChangeResearchCenter DepartmentofGeographyUniversityCollegeLondon26BedfordWayWC1H0APUK

Short cores of about 80-cm retrieved from three main basins of the deepw.ter areas in Qinghai Lake, the largest inland enclosed lake in China, w.re studied. Stable isotopes of authigenic carbonates, grain-size, carbonate and organic matter content at 5-year resolution are used to reconstruct the climatic history over the last 800 years in the Northeastern Tibetan Plateau. Chronology w.s established according to 210Pb dating and 137Cs methods and the core correlation. It is found that cores from different deep basins of the lake can be w.ll correlated. The sedimentary rate is highest in the w.stern basin of the lake and low.st in the east. In the southern basin of the lake w.ere the short core Qing-6 is located, the recent average sedimentation rate is 0.1004 cm/yr. Variations in effective precipitation recorded by the oxygen isotopes and grain size data during the last 800 years are consistent w.th the glacial accumulation record form the Dunde and Guliya ice cores. A dry climate lasted for 300 years from 1200 AD to 1500 AD, follow.d by a w.t period from 1500 to 1560 AD. The tw. dry periods, 1560 to 1650 AD and 1780 to 1850 AD, w.re the results of southw.st monsoon w.akening. The effective precipitation generally increased since 1650 AD due to the strengthening of the Asian Southw.st Monsoon, resulting in a w.t period until the 1950s. Except the early stage, the Little Ice Age on the Plateau is characterized by increased effective moisture. Organic mat- ter content, w.th nearly 200-year cycles, show. similar trend w.th the atmospheric delta carbon-14 before the 1850s, indicating that the bioproductivity responds to solar activity.

关键词：中国西藏东北部青海湖沉积岩心古气候碳酸盐氧同位素有效降水量

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Nonsingularity of Grain-like cascade FSRs via semi-tensor product

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Science China(Information Sciences) 2018年第1期61卷 58-69页

作者： Jianquan LU Meilin LI Yang LIU Daniel w.C.HO Jrgen KURTHS School of Mathematics Southeast University College of Mathematics Physics and Information Engineering Zhejiang Normal University Department of Mathematics City University of Hong Kong Potsdam Institute for Climate Impact Research

In this paper, Grain-like cascade feedback shift registers(FSRs) are regarded as tw. Boolean netw.rks(BNs), and the semi-tensor product(STP) of the matrices is used to convert the Grain-like cascade FSRs into an equivalent linear equation. Based on the STP, a novel method is proposed herein to investigate the nonsingularity of Grain-like cascade FSRs. First, w. investigate the property of the state transition matrix of Grain-like cascade FSRs. w. then propose their sufficient and necessary nonsingularity condition. Next,w. regard the Grain-like cascade FSRs as Boolean control netw.rks(BCNs) and further provide a sufficient condition of their nonsingularity. Finally, tw. examples are provided to illustrate the results obtained in this paper.

关键词： Grain-like cascade FSRs Boolean control netw.rks Boolean netw.rks semi-tensor product nonsingularity

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Acta Mechanica Sinica 2010年第4期26卷 567-572页

作者： D.J.Colquitt A.B.Movchan I.S.Jones w.Daniels Department of Mathematical Sciences University of Liverpool School of Engineering John Moores University Serco Assurance w.lton House 404 The QuadrantBirchwood ParkRisleyWarringtonCheshireWA3 6GAUK

The paper presents a computational model for elastic w.ves in a structured w.ld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of w.ves w.th the micro-structure of the w.ld. Effects of localisation and channeling of w.ves are addressed. A model of a grain structure w.thin the w.ld is also considered.

关键词： Macro-structured w.lds w.ves in stratified media Dispersion Localisation

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3-D discontinuum numerical modeling of subsidence incorporating ore extraction and backfilling operations in an underground iron mine in China

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International Journal of Mining Science and Technology 2017年第2期27卷 191-201页

作者： Huang Gang Kulatilake Pinnaduw. H.S.w. Shreedharan Srisharan Cai Sijing Song Hongqing School of Resources and Environmental Engineering Wuhan University of Technology School of Civil and Environmental Engineering University of Science and TechnologyBeijing Rock Mass Modeling and Computational Rock Mechanics Laboratories University of Arizona

An underground iron mine in China has been used as a case-study to research the subsidence due to ore extraction and backfilling during open stoping operations. A 3-D discontinuum numerical model w.s built incorporating geologic complexities including faults and interfaces betw.en different lithologies,and the stoping and backfilling sequence adopted from the mine plans. The stoping w.s carried out in tw. vertically stacked horizontal layers, w.th a total of 16 stopes. Large displacements of up to 50 cm w.re observed along the roof of the stopes, and a maximum surface subsidence of 22.5 cm w.s *** w.s found to eliminate subsequent displacements and subsidence. The extraction of the upper orebody w.s found to influence displacements in the low.r orebody. Finally, a subsidence profile w.s constructed to show.the subsidence at all locations along the length of the surface and region of influence on the surface.

关键词： Underground iron mine Discontinuum numerical modeling Open stoping Backfill Subsidence

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A system for probing Casimir energy corrections to the condensation energy

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Microsystems & Nanoengineering 2020年第1期6卷 1-12页

作者： Diego Perez-Morelo Alexander Stange Richard w.Lally Law.ence K.Barrett Matthias Imboden Abhishek Som David K.Campbell Vladimir A.Aksyuk David J.Bishop Department of ECE Boston UniversityBostonMA 02215USA Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20899USA Institute for Research in Electronics and Applied Physics&Maryland NanoCenter University of MarylandCollege ParkMD 20742USA Division of MSE Boston UniversityBostonMA 02215 USA 54K-MEMS Sarl Rue des Lavannes 172072 St BlaiseSwitzerland Department of Physics Boston UniversityBostonMA 02215USA Department of ME Boston UniversityBostonMA 02215USA Department of BME Boston UniversityBostonMA 02215USA

In this article,w. present a nanoelectromechanical system(NEMS)designed to detect changes in the Casimir *** Casimir effect is a result of the appearance of quantum fluctuations in an electromagnetic *** experiments have used nano-or microscale parallel plate capacitors to detect the Casimir force by measuring the small attractive force these fluctuations exert betw.en the tw. *** this new.set of experiments,w. aim to directly detect the shifts in the Casimir energy in a vacuum due to the presence of the metallic parallel plates,one of w.ich is a superconductor.A change in the Casimir energy of this configuration is predicted to shift the superconducting transition temperature(T_(c))because of the interaction betw.en it and the superconducting condensation *** our experiment,w. take a superconducting film,carefully measure its transition temperature,bring a conducting plate close to the film,create a Casimir cavity,and then measure the transition temperature *** expected shifts are smaller than the normal shifts one sees in cycling superconducting films to cryogenic temperatures,so using a NEMS resonator in situ is the only practical w.y to obtain accurate,reproducible *** a thin Pb film and opposing Au surface,w. observe no shift in T_(c)>12µK dow. to a minimum spacing of~70 nm at zero applied magnetic field.

关键词： cycling energy film

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Perception of artificial conspecifics by bearded dragons(Pogona vitticeps)

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Integrative Zoology 2019年第2期14卷 214-222页

作者： Anna FROHNw.ESER Thomas w.PIKE John C.MURRAY Anna w.LKINSON School of Life Sciences University of LincolnLincolnUK School of Computer Science University of LincolnLincolnUK w.ldlife Research Center Kyoto UniversityKyotoJapan

Artificial animals are increasingly used as conspecific stimuli in animal behavior ***,researchers often have an incomplete understanding of how.the species under study perceives conspecifics,and,hence,w.ich features are needed for a stimulus to be perceived *** investigate the features that bearded dragons(Pogona vitticeps)attend to,w. measured their lateralized eye use w.en assessing a successive range of *** ranged through several stages of realism in artificial conspecifics,to see how.features such as color,the presence of eyes,body shape and motion influence *** found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific,as w.ll as the artificial conspecific’s ***,this approach can inform the design of robotic animals that elicit biologically-meaningful responses in live animals.

关键词： bearded dragons conspecifics lateralized eye use perception

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Thismia tentaculata(Burmanniaceae tribe Thismieae) from Hong Kong:first record of the genus and tribe from continental China

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Journal of Systematics and Evolution 2009年第6期47卷 605-607页

作者： George w.C.HO Shek Shing MAR Richard M.K.SAUNDERS 812 Fu Yuen HouseChuk Yuen South EstateHong KongChina Ying w. College Hong KongChina Division of Ecology and Biodiversity School of Biological SciencesThe University of Hong Kong

Populations of Thismia tentaculata(Burmanniaceae tribe Thismieae) are described and illustrated from Tai Mo Shan in Hong Kong,southern *** represents the first report of the genus and tribe from continental China.

关键词： Burmanniaceae Hong Kong new.record Thismiaceae Thismia tentaculata

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Channel capacity investigation of a linear massive MIMO system using spherical w.ve model in LOS scenarios

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Science China(Information Sciences) 2016年第2期59卷 45-59页

作者： Liu LIU David w.MATOLAK Cheng TAO Yongzhi LI Bo AI Houjin CHEN Institute of Broadband w.reless Mobile Communications Beijing Jiaotong University Department of Electrical Engineering University of South Carolina National Mobile Communications Research Laboratory Southeast University

Massive multiple-input multiple-output(MIMO) is a key technology for the 5th generation(5G)of w.reless communication systems. The traditional plane w.ve channel model(Pw.) is often not suitable for the large antenna structure, and in certain cases should be replaced by the more accurate spherical w.ve model(Sw.). By using the spherical w.ve characterization method, this paper investigates the channel capacity performance of a linear massive MIMO system in line-of-sight(LOS) scenarios. Tw. types of access settings, the point to point(PTP) system and multi-user(MU) system, are considered. In the PTP setting, a geometrical optimization is performed to obtain configurations that are able to generate a full rank channel matrix for a linear massive MIMO system, w.ich yields full spatial diversity even in LOS scenarios. Compared w.th the approximate and commonly applied rank-1 Pw., this is very useful for fixed w.reless access and radio relay systems requiring high throughput. For the MU case, w. compare the eigenvalue distributions of the LOS channels using the plane w.ve and spherical w.ve characterization method, and sum rate results are obtained by Monte Carlo simulations. The results show.that MU systems using the more realistic and accurate Sw. can achieve a higher sum rate than results from the Pw.. This is beneficial and informative w.en designing massive MIMO w.reless netw.rks.

关键词： massive MIMO channel model plane w.ve model spherical w.ve model channel capacity

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VOLUMETRIC MASS TRANSFER COEFFICIENT BETw.EN SLAG AND METAL IN COMBINED BLOw.NG CONVERTER

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 91-95页

作者： Z.H.w. Z.S.Zou w.w. SchoolofMaterialsandMetallurgy NortheasternUniversityShenyang110004China CentralIron＆SteelResearchInstitute Beijing100081China

The effects of operation parameters of combined blow.ng converter on the volumetric mass transfer coefficient betw.en slag and steel are studied w.th a cold model w.th w.ter simulating steel, oil simulating slag and benzoic acid as the transferred substance betw.en w.ter and oil. The results show.that, w.th lance level of 2.1m and the top blow.ng rate of 25000Nm3/h, the volumetric mass transfer coefficient changes most significantly w.en the bottom blow.ng rate ranges from 384 to 540Nm3/h. The volumetric mass transfer coefficient reaches its maximum w.en the lance level is 2.1m, the top blow.ng rates is 30000Nm3/h, and the bottom blow.ng rate is 384Nm3/h w.th tuyeres located symmetrically at 0.66D of the converter bottom.

关键词： combined blow.ng converter cold modeling volumetric mass transfer coefficient operational parameter

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Effect of fibrinolytic therapy on ST-elevation myocardial infarction clinical outcomes during the COVID-19 pandemic:A systematic review.and meta-analysis

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w.rld Journal of Cardiology 2023年第6期15卷 309-323页

作者： Anw.r Khedr Hussam Al Hennaw. Muhammed Khuzzaim Khan Mostafa Elbanna Abbas B Jama Ekaterina Proskuriakova Hisham Mushtaq mikael Mir Sydney Boike Ibtisam Rauf Aalaa Eissa Meritxell Urtecho Thoyaja Koritala Nitesh Jain Lokesh Goyal Salim Surani Syed A Khan Department of Internal Medicine BronxCare Health SystemBronxNY 10457United States Department of Internal Medicine Jefferson Abington HospitalAbingtonPA 19001United States Department of Internal Medicine Dow University of Health ScienceKarachi 74200Pakistan Department of Internal Medicine Rochester Regional HealthRochesterNY 14621United States Department of Critical Care Mayo Clinic Health SystemMankatoMN 56001United States Department of Internal Medicine Mount Sinai HospitalChicagoIL 60608United States Department of Internal Medicine St.Vincent's Medical CenterBridgeportCT 06606United States Department of Medicine University of MinnesotaMinneapolisMN 55455United States Department of Medicine St.George's UniversitySchool of MedicineSt George SW170REGrenada Department of Medicine KFS UniversityKFS 33511Egypt Department of Medicine Robert D and Patricia E.Kern Center of Health Care DeliveryMayo ClinicRochesterMN 55905United States Department of Hospital Medicine Mayo Clinic Health SystemMankatoMN 56001United States Department of Medicine Mayo Clinic Health SystemMankatoMN 56001United States Department of Hospital Medicine Christus Sphon Hospital-shorelineCorpus ChristoTX 78404United States Department of Pulmonary Critical Care&Sleep MedicineTexas A&M UniversityCollege StationTX 77843United States Department of Critical Care Medicine Mayo Clinic Health SystemMankatoMN 56001United States

BACKGROUND ST-elevation myocardial infarction(STEMI)is the result of transmural ischemia of the myocardium and is associated w.th a high mortality *** percutaneous coronary intervention(PPCI)is the recommended first-line treatment strategy for patients w.th *** timely delivery of PPCI became extremely challenging for STEMI patients during the coronavirus disease 2019(COVID-19)pandemic,leading to a projected steep rise in *** delays w.re overcome by the shift from first-line therapy and the development of modern fibrinolytic-based *** is unclear w.ether fibrinolytic-based reperfusion therapy is effective in improving STEMI *** To determine the incidence of fibrinolytic therapy during the COVID-19 pandemic and its effects on STEMI clinical *** PubMed,Google Scholar,Scopus,w.b of Science,and Cochrane Central Register of Controlled Trials w.re queried from January 2020 up to February 2022 to identify studies investigating the effect of fibrinolytic therapy on the prognostic outcome of STEMI patients during the *** outcomes w.re the incidence of fibrinolysis and the risk of all-cause *** w.re meta-analyzed using the random effects model to derive odds ratios(OR)and 95%confidence *** assessment w.s carried out using the New.astle-Ottaw. *** Fourteen studies including 50136 STEMI patients(n=15142 in the pandemic arm;n=34994 in the pre-pandemic arm)w.re *** mean age w.s 61 years;79%w.re male,27%had type 2 diabetes,and 47%w.re *** w.th the pre-pandemic period,there w.s a significantly increased overall incidence of fibrinolysis during the pandemic period[OR:1.80(1.18 to 2.75);I2=78%;P=0.00;GRADE:Very low..The incidence of fibrinolysis w.s not associated w.th the risk of all-cause mortality in any *** countries w.th a low.and middle-income status reported a higher incidence of fibrinolysis[OR:5.16(2.18 to 12.22);I2=81%;P=0.00;GRADE:Very lo

关键词： ST-elevation myocardial infarction Myocardial infarction Thrombolytic therapy Fibrinolysis COVID-19 Pandemics

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