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Wintertime Stratospheric Anomalies-Part I: Warm Pools

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Advances in Atmospheric Sciences 1992年第3期9卷 299-310页

作者： y.l.McHall Dept. of Meteorology University of Edinburgh EH9 3JZ U. K.he stratospheric worm pools called the 4-day wave also are mainly the temperature anomalies in the polar regions of winter hemisphere. It will be shown that their occurrence propagation speed and specific structure can be explained by the lower frequency coherent heating resulting from the wave interaction in the breaking layers of the stratosphere. Although their vertical phase slope is negligibly small the warm pools cannot be considered as a barotropic anomaly.

The stratospheric worm pools, called the 4-day wave also, are mainly the temperature anomalies in the polar regions of winter hemisphere. It will be shown that their occurrence, propagation speed and specific structure can be explained by the lower frequency coherent heating resulting from the wave interaction in the breaking layers of the stratosphere. Although their vertical phase slope is negligibly small, the warm pools cannot be considered as a barotropic anomaly.

关键词： Wintertime Stratospheric Anomalies-Part I Warm Pools

Wintertime Stratospheric Anomalies-Part II: Sudden Warmings

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Advances in Atmospheric Sciences 1992年第3期9卷 311-322页

作者： y.l.McHall Dept. of Meteorology University of Edinburgh EH9 3JZ U. K.he process of stratospheric sudden warmings from development of planetary waves to.the sudden cooling after reversal of mean zonal circulation will be studied with the primitive equations of heat and momentum balances. It will be explained that the sudden warmings may occur only in the polar regions of winter stratosphere where zonal mean temperature decreases poleward. The heating rate in the order of major warmings is produced by developed planetary waves in the stratospheric breaking layers. The particular perturbation structure characterized by large amplitude of wave 1 together with minimum of wave 2 discovered by Labitzke (1977) is crucial for initiation of major warmings. The cooling by the same mechanism can be produced in the regions with reversed mean temperature gradient.

The process of stratospheric sudden warmings from development of planetary waves *** sudden cooling after reversal of mean zonal circulation will be studied with the primitive equations of heat and momentum balances. It will be explained that the sudden warmings may occur only in the polar regions of winter stratosphere where zonal mean temperature decreases poleward. The heating rate in the order of major warmings is produced by developed planetary waves in the stratospheric breaking layers. The particular perturbation structure characterized by large amplitude of wave 1 together with minimum of wave 2 discovered by labitzke (1977) is crucial for initiation of major warmings. The cooling by the same mechanism can be produced in the regions with reversed mean temperature gradient.

关键词： Wintertime Stratospheric Anomalies-Part II Sudden Warmings

Scientific Value Weights more than Being Open or Toll Access:An analysis of the OA advantage in Nature and Science

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Journal of Data and Information Science 2021年第4期6卷 62-75页

作者： Howell y.Wang Shelia x.Wei Cong Cao xianwen Wang Fred y.ye International Joint Informatics laboratory&Jiangsu Key laboratory of Data Engineering and Knowledge Service School of Information ManagementNanjing UniversityNanjing 210023China Nottingham university Business School China University of Nottingham Ningbo ChinaNingbo315100China WISE lab. Dalian University of TechnologyDalian 116024China

Purpose:We attempt to find out whether OA or TA really affects the dissemination of scientific ***/methodology/approach:We design the indicators,hot-degree,and R-index to indicate a topic OA or TA ***,according to the OA classification of the Web of Science(WoS),we collect data from the WoS by downloading OA and TA articles,letters,and reviews published in Nature and Science during 2010–*** papers are divided into three broad disciplines,namely biomedicine,physics,and ***,taking a discipline in a journal and using the classical latent Dirichlet Allocation(lDA)to cluster 100 topics of OA and TA papers respectively,we apply the Pearson correlation coefficient to match the topics of OA and TA,and calculate the hot-degree and R-index of every OA-TA topic ***,characteristics of the discipline can be *** qualitative comparison,we choose some high-quality papers which belong to Nature remarkable papers or Science breakthroughs,and analyze the relations between OA/TA and citation ***:The result shows that OA hot-degree in biomedicine is significantly greater than that of TA,but significantly less than that of TA in *** on the R-index,it is found that OA advantages exist in biomedicine and TA advantages do in ***,the dissemination of average scientific discoveries in all fields is not necessarily affected by OA or ***,OA promotes the spread of important scientific discoveries in high-quality *** limitations:We lost some citations by ignoring other open sources such as arxiv and *** limitation came from that Nature employs some strong measures for access-promoting subscription-based articles,on which the boundary between OA and TA became *** implications:It is useful to select hot topics in a set of publications by the hotdegree *** finding comprehensively reflects the differences of OA and TA in different disciplines,which is a u

关键词： Open access Toll access Scientific discovery Academic dissemination Data analysis

A dynamic range extension system for lHAASOWCDA-1

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Radiation Detection Technology and Methods 2021年第4期5卷 520-530页

作者： F.Aharonian Q.An Axikegu l.x.Bai y.x.Bai y.W.Bao D.Bastieri x.J.Bi y.J.Bi H.Cai J.T.Cai Z.Cao Z.Cao J.Chang J.F.Chang x.C.Chang B.M.Chen J.Chen l.Chen l.Chen l.Chen M.J.Chen M.l.Chen Q.H.Chen S.H.Chen S.Z.Chen T.l.Chen x.l.Chen y.Chen N.Cheng y.D.Cheng S.W.Cui x.H.Cui y.D.Cui B.Z.Dai H.l.Dai Z.G.Dai Danzengluobu D.della Volpe B.D’Ettorre Piazzoli x.J.Dong J.H.Fan y.Z.Fan Z.x.Fan J.Fang K.Fang C.F.Feng l.Feng S.H.Feng y.l.Feng B.Gao C.D.Gao Q.Gao W.Gao M.M.Ge l.S.Geng G.H.Gong Q.B.Gou M.H.Gu J.G.Guo x.l.Guo y.Q.Guo y.y.Guo y.A.Han H.H.He H.N.He J.C.He S.l.He x.B.He y.He M.Heller y.K.Hor C.Hou x.Hou H.B.Hu S.Hu S.C.Hu x.J.Hu D.H.Huang Q.l.Huang W.H.Huang x.T.Huang y.Huang Z.C.Huang F.Ji x.l.Ji H.y.Jia K.Jiang Z.J.Jiang C.Jin D.Kuleshov K.levochkin B.B.li C.li C.li F.li H.B.li H.C.li H.y.li J.li K.li W.l.li x.li x.li x.R.li y.li y.Z.li Z.li Z.li E.W.liang y.F.liang S.J.lin B.liu C.liu D.liu H.liu H.D.liu J.liu J.l.liu J.S.liu J.y.liu M.y.liu R.y.liu S.M.liu W.liu y.N.liu Z.x.liu W.J.long R.lu H.K.lv B.Q.Ma l.l.Ma x.H.Ma J.R.Mao A.Masood W.Mitthumsiri T.Montaruli y.C.Nan B.y.Pang P.Pattarakijwanich Z.y.Pei M.y.Qi D.Ruffolo V.Rulev A.Sáiz l.Shao O.Shchegolev x.D.Sheng J.R.Shi H.C.Song yu.V.Stenkin V.Stepanov Q.N.Sun x.N.Sun Z.B.Sun P.H.T.Tam Z.B.Tang W.W.Tian B.D.Wang C.Wang H.Wang H.G.Wang J.C.Wang J.S.Wang l.P.Wang l.y.Wang R.N.Wang W.Wang W.Wang x.G.Wang x.J.Wang x.y.Wang y.D.Wang y.J.Wang y.P.Wang Z.Wang Z.Wang Z.H.Wang Z.x.Wang D.M.Wei J.J.Wei y.J.Wei T.Wen C.y.Wu H.R.Wu S.Wu W.x.Wu x.F.Wu S.Q.xi J.xia J.J.xia G.M.xiang G.xiao H.B.xiao G.G.xin y.l.xin y.xing D.l.xu R.x.xu l.xue D.H.yan C.W.yang F.F.yang J.y.yang l.l.yang M.J.yang R.Z.yang S.B.yang y.H.yao Z.G.yao y.M.ye l.Q.yin N.yin x.H.you Z.y.you y.H.yu Q.yuan H.D.Zeng T.x.Zeng W.Zeng Z.K.Zeng M.Zha x.x.Zhai B.B.Zhang H.M.Zhang H.y.Zhang J.l.Zhang J.W.Zhang l.Zhang l.Zhang l.x.Zhang P.F.Zhang P.P.Zhang R.Zhang S.R.Zhang S.S.Zhang x.Zhang x.P.Zhang y.Zhang y.Zhang y.F.Zhang y.l.Zhang B.Zhao J.Zhao l.Zhao l.Z.Zhao S.P.Zhao F.Zheng y.Zheng B.Zhou H.Zhou J.N.Zhou Key laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China TIANFu Cosmic Ray Research Center ChengduSichuanChina State Key laboratory of Particle Detection and Electronics BeijingChina university of Science and Technology of China Hefei 230026AnhuiChina Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Physics Peking UniversityBeijing 100871China Center for Astrophysics Guangzhou UniversityGuangzhou 510006GuangdongChina School of Physics and Astronomy&School of Physics(Guangzhou) Sun Yat-sen UniversityZhuhai 519000GuangdongChina School of Physical Science and Technology Guangxi UniversityNanning 530004GuangxiChina Hebei Normal university Shijiazhuang 050024HebeiChina School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001HenanChina School of Astronomy and Space Science Nanjing UniversityNanjing 210023JiangsuChina Key laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023JiangsuChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237ShandongChina Key laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Tsung-Dao lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031SichuanChina College of Physics Sichuan UniversityChengdu 610065SichuanChina Key laboratory of Cosmic Rays(Tibet university) Ministry of EducationLhasa 850000TibetChina School of Physics

Purpose The main scientific goal of lHAASO-WCDA is to survey gamma-ray sources with energy from 100 GeV to 30 *** observe high-energy shower events,especially to measure the energy spectrum of cosmic rays from 100 TeV to 10 PeV,a dynamic range extension system(WCDA++)is designed to use a 1.5-inch PMT with a dynamic range of four orders of magnitude for each cell in *** The dynamic range is extended by using these PMTs to measure the effective charge density in the core region of air shower events,which is an important parameter for identifying the composition of primary *** and Conclusion The system has been running for more than one *** this paper,the details of the design and performance of WCDA++are presented.

关键词： lHAASO-WCDA WCDA++ Water Cherenkov detector Performance

Plastic deformation of a Zr-based bulk metallic glass fabricated by selective laser melting

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Journal of Materials Science & Technology 2021年第1期60卷 139-146页

作者： l.Deng K.Kosiba R.limbach l.Wondraczek u.Kühn S.Pauly IFW Dresden Institute for Complex MaterialsHelmholtzstraße 20D-01069DresdenGermany Otto Schott Institute of Materials Research University of JenaFraunhoferstraße 6D-07743JenaGermany university of Applied Sciences Aschaffenburg Würzburger Straße 45D-63743AschaffenburgGermany

Fully amorphous Zr_(52.5)Cu_(17.9)Ni_(14.6)Al_(10)Ti_(5) bulk metallic glass(BMG) samples with a relative density exceeding 98% were fabricated via selective laser melting(SlM).High fracture stresses of around1700 MPa and a reproducible plastic strain of about 0.5% were obtained for cylindrical SlM *** analysis of the observed serrations during compressive loading implies that the shear-band dynamics in the additively manufactured samples distinctly differ from those of the as-cast *** phenomenon appears to originate from the presence of uniformly dispersed spherical pores as well as from the more pronounced heterogeneity of the glass itself as revealed by instrumented *** these heterogeneities,the shear bands are straight and form in the plane of maximum shear *** manufacturing,hence,might not only allow for producing large BMG samples with complex geometries but also for manipulating their deformation behaviour through tailoring porosity and structural heterogeneity.

关键词： Powder bed fusion Selective laser melting Bulk metallic glass Serrated flow Heterogeneity

Teaching and learning Chinese through Immersion:A Case Study from the North American Context

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Frontiers of Education in China 2020年第1期15卷 99-141页

作者： Chan lÜ Department of Asian languages&literature University of WashingtonSeattleWA 98195-3521USA

With the promise of achieving bilingualism,biliteracy,and cultural pluralism,Chinese immersion programs for students from kindergarten to 12th grade(K-12)in North America,especially the uS,have been proliferating in the past two *** on this rapidly growing population of non-native Chinese learners is also *** research synthesis focuses on 35 selected studies published in recent years on Chinese immersion in both Chinese and English language journals and *** review found that researchers are exploring a wide range of issues with respect to language and literacy development in Chinese immersion programs,including academic achievement in English,language and literacy acquisition in Chinese,instructional strategies and classroom interaction,as well as learners’language use and its sociolinguistic *** studies reflect a growing interest in and demand for learning more about the lesser-researched Chinese foreign language(CFl)learner population,and this review concludes with suggestions for future research on Chinese immersion based on its curricular features as well as specific considerations for conducting research with young,emergent bilingual and biliterate learners.

关键词： K-12 education Chinese immersion programs Chinese as a foreign language(CFl) academic achievement bilingual and biliteracy acquisition instructional strategies classroom interaction learner language

Identification of Hammerstein systems with asymmetric dead-zone nonlinearities using canonical parameterized model

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控制理论与应用（英文版） 2012年第4期10卷 511-516页

作者： xiaohua lü xuemei REN School of Automation Beijing Institute of Technology

A non-iterative identification method with parameterization of the unknown dead-zone is proposed for Hammerstein systems in presence of asymmetric dead-zone nonlinearities. The canonical parameterized model which is a single expression without segmentation is utilized to describe the dead-zone, based on which a universal-type parametric model can be established to approximate the entire system. This model can be established without separating the nonlinear part from the linear part. The dead-zone parameters and the coefficients in the linear transfer function can be estimated simultaneously according to the proposed algorithm. Numerical experiments are presented to illustrate the effectiveness of the proposed scheme.

关键词： Hammerstein systems Asymmetric dead-zone nonlinearity Canonical parameterized model System identification

Performance of lHAASO-WCDA and observation of the Crab Nebula as a standard candle

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Chinese Physics C 2021年第8期45卷 166-181页

作者： F.Aharonian Q.An Axikegu l.x.Bai y.x.Bai y.W.Bao D.Bastieri x.J.Bi y.J.Bi H.Cai J.T.Cai Z.Cao Z.Cao J.Chang J.F.Chang x.C.Chang B.M.Chen J.Chen l.Chen l.Chen l.Chen M.J.Chen M.l.Chen Q.H.Chen S.H.Chen S.Z.Chen T.l.Chen x.l.Chen y.Chen N.Cheng y.D.Cheng S.W.Cui x.H.Cui y.D.Cui B.Z.Dai H.l.Dai Z.G.Dai Danzengluobu D.della Volpe B.D'Ettorre Piazzoli x.J.Dong J.H.Fan y.Z.Fan Z.x.Fan J.Fang K.Fang C.F.Feng l.Feng S.H.Feng y.l.Feng B.Gao C.D.Gao Q.Gao W.Gao M.M.Ge l.S.Geng G.H.Gong Q.B.Gou M.H.Gu J.G.Guo x.l.Guo y.Q.Guo y.y.Guo y.A.Han H.H.He H.N.He J.C.He S.l.He x.B.He y.He M.Heller y.K.Hor C.Hou x.Hou H.B.Hu S.Hu S.C.Hu x.J.Hu D.H.Huang Q.l.Huang W.H.Huang x.T.Huang Z.C.Huang F.Ji x.l.Ji H.y.Jia K.Jiang Z.J.Jiang C.Jin D.Kuleshov K.levochkin B.B.li C.li C.li F.li H.B.li H.C.li H.y.li J.li K.li W.l.li x.li x.li x.R.li y.li y.Z.li Z.li Z.li E.W.liang y.F.liang S.J.lin B.liu C.liu D.liu H.liu H.D.liu J.liu J.l.liu J.S.liu J.y.liu M.y.liu R.y.liu S.M.liu W.liu y.N.liu Z.x.liu W.J.long R.lu H.K.lv B.Q.Ma l.l.Ma x.H.Ma J.R.Mao A.Masood W.Mitthumsiri T.Montaruli y.C.Nan B.y.Pang P.Pattarakijwanich Z.y.Pei M.y.Qi B.Q.Qiao D.Ruffolo V.Rulev A.Saiz l.Shao O.Shchegolev x.D.Sheng J.R.Shi H.C.Song yu.V.Stenkin V.Stepanov Q.N.Sun x.N.Sun Z.B.Sun P.H.T.Tam Z.B.Tang W.W.Tian B.D.Wang C.Wang H.Wang H.G.Wang J.C.Wang J.S.Wang l.P.Wang l.y.Wang R.N.Wang W.Wang W.Wang x.G.Wang x.J.Wang x.y.Wang y.D.Wang y.J.Wang y.P.Wang Z.Wang Z.Wang Z.H.Wang Z.x.Wang D.M.Wei J.J.Wei y.J.Wei T.Wen C.y.Wu H.R.Wu S.Wu W.x.Wu x.F.Wu S.Q.xi J.xia J.J.xia G.M.xiang G.xiao H.B.xiao G.G.xin y.l.xin y.xing D.l.xu R.x.xu l.xue D.H.yan C.W.yang F.F.yang J.y.yang l.l.yang M.J.yang R.Z.yang S.B.yang y.H.yao Z.G.yao y.M.ye l.Q.yin N.yin x.H.you Z.y.you y.H.yu Q.yuan H.D.Zeng T.x.Zeng W.Zeng Z.K.Zeng M.Zha x.x.Zhai B.B.Zhang H.M.Zhang H.y.Zhang J.l.Zhang J.W.Zhang l.Zhang l.Zhang l.x.Zhang P.F.Zhang P.P.Zhang R.Zhang S.R.Zhang S.S.Zhang x.Zhang x.P.Zhang y.Zhang y.Zhang y.F.Zhang y.l.Zhang B.Zhao J.Zhao l.Zhao l.Z.Zhao S.P.Zhao F.Zheng y.Zheng B.Zhou H.Zhou J.N.Zhou Key laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China TIANFu Cosmic Ray Research Center ChengduSichuanChina State Key laboratory of Particle Detection and Electronics China university of Science and Technology of China Hefei 230026China Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China National Space Science Center Chinese Academy of SciencesBeijing 100190China School of Physics Peking UniversityBeijing 100871China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China School of Physics and Astronomy&School of Physics(Guangzhou) Sun Yat-sen UniversityZhuhai 519082China School of Physical Science and Technology Guangxi UniversityNanning 530004China Hebei Normal university Shijiazhuang 050024China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China Key laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Tsung-Dao lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China College of Physics Sichuan UniversityChengdu 610065China Key laboratory of Cosmic Rays(Tibet university) Ministry of EducationLhasa 850000China School of Physics and Technology Wuhan UniversityWuhan 430072China School of Physics and Astronomy Yunnan University

The first Water Cherenkov detector of the lHAASO experiment(WCDA-1)has been operating since April *** data for the first year have been analyzed to test its performance by observing the Crab Nebula as a standard *** WCDA-1 achieves a sensitivity of 65 mCu per year,with a statistical threshold of 5 *** accomplish this,a 97.7%cosmic-ray background rejection rate around 1 TeV and 99.8%around 6 TeV with an ap proximate photon acceptance of 50%is achieved after applying an algorithm to separate gamma-induced *** angular resolution is measured using the Crab Nebula as a point source to be approximately 0.45°at 1 TeV and better than 0.2°above 6 TeV,with a pointing accuracy better than 0.05°.These values all match the design *** energy resolution is found to be 33%for gamma rays around 6 *** spectral energy distribution of the Crab Nebula in the range from 500 GeV to 15.8 TeV is measured and found to be in agreement with the results from other TeV gamma ray observatories.

关键词： lHAASO-WCDA Crab Nebula angular resolution spectral energy distribution

High-Speed Friction Stir Welding of T6-Treated B4Cp/6061Al Composite

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Acta Metallurgica Sinica(English letters) 2020年第1期33卷 67-74页

作者： y.Z.li y.N.Zan Q.Z.Wang B.l.xiao Z.y.Ma Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China university of Science and Technology of China Shenyang 110016China

T6-treated 20 wt% B4 Cp/6061 Al sheets were joined under welding speeds of 400–1200 mm/min by friction stir welding(FSW) with a threaded cermet pin. The macro-defect-free FSW joints could be achieved at high welding speeds up to 1200 mm/min, but larger plunge depth was required at the welding speeds of 800 and 1200 mm/min to eliminate the tunnel defect. In the nugget zone(NZ) of the joints, the B4 C particles were broken up and uniformly redistributed. The NZ exhibited lower hardness than the base metal(BM), and the hardness value almost did not change with increasing welding speed, attributable to the dissolution of precipitates. Compared with the BM, the joints showed lower tensile strength. As the welding speed increased from 400 to 800 mm/min, the joint efficiencies were nearly the same and up to ~ 73%. When the welding speed increased up to 1200 mm/min, the tensile strength significantly decreased, due to the occurrence of kissing bond defect at the bottom of the NZ. With increasing welding speed, the fracture location of the joints transferred gradually from the heat-affected zone to the NZ due to the kissing bond defects.

关键词： Metal-matrix composites Microstructures Mechanical properties Friction stir welding High-speed welding