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Chinese Journal of Aeronautics 2015年第1期28卷 152-163页

作者： tian Yongliang Liu Hu Yin jiao Luo Mingqiang Wu Guanghui School of Aeronautic Science and Engineering Beihang University Chengdu Aircraft Design Institute Commercial Aircraft Corporation of China Ltd.

Simulation-based training is a promising way to train a carrier flight deck crew because of the complex and dangerous working environment. Quantitative evaluation of simulation-based training quality is vital to make simulation-based training practical for aircraft carrier *** paper develops a personal computer-based aircraft carrier marshalling simulation system and a cave automatic virtual environment（CAVE）-based immersive environment. In order to compare the training effectiveness of simulation-based training and paper-based training, a learning cubic model is proposed and a contrast experiment is carried out as well. The experimental data is analyzed based on a simplified Kirkpatrick＇s model. The results show that simulation-based training is better than paper-based training by 26.80% after three rounds of testing, which prove the effectiveness of simulation-based aircraft carrier marshalling training.

关键词： aircraft cubic dangerous simplified questionnaire vital train deviation pyramid judge

Construction of ecological security patterns and ecological restoration zones in the city of Ningbo,China

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Journal of Geographical Sciences 2022年第4期32卷 663-681页

作者： ZHANG Haitao LI Jialin tian Peng pu Ruiliang CAO Luodan Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211ZhejiangChina Ningbo Universities Collaborative Innovation Center for Land and Marine Spatial Utilization and Governance Research at Ningbo University Ningbo 315211ZhejiangChina School of Geosciences University of South FloridaTampaFL 33620-5250USA

Studying an ecological restoration zoning process under the background of ecological security patterns is of great significance to the rapid adjustment and optimization of a landscape *** this study,a remote sensing ecological index and a morphological spatial pattern analysis method were used to assess the quality of habitats and identify ecological sources in the city of Ningbo;ecological corridors,ecological pinch points,and ecological barrier points were extracted by using a circuit theory to construct ecological security patterns and ecological restoration *** results indicate:(1)There were 47 ecological sources,and 83 key ecological corridors in Ningbo,and the ecological land area was about 1898.39 km^(2),accounting for 19.89%of the total study area.(2)The ecological source areas were distributed in“one patch and three belts”,and the low-resistance ecological corridors were concentrated in southern Yuyao city,western Haishu district,and central and western Fenghua district;the ecological network in the western and southern regions was dense.(3)There were four types of ecological restoration zones that need to be established,which were prioritized restoration zones,prioritized protection zones,key conservation zones,and general conservation zones distributed hierarchically from inner part towards outside.(4)Ninghai county,Yuyao city,and Fenghua district had large ecological land areas,however,prioritized restoration and protection zones in Ninghai and Fenghua were also *** analysis results are expected to provide a reference for optimizing a territorial ecological space in a city.

关键词： remote sensing ecological index ecological security patterns circuit theory ecological restoration zones Ningbo City

Coherent Transfer of Excitation in a Nanomechanical Artificial Lattice

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Chinese Physics Letters 2020年第1期37卷 14-18页

作者： Liang Zhang tian tian pu Huang Shaochun Lin Jiangfeng Du CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics University of Science and Technology of ChinaHefei 230026 Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026 National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093 Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026

We realize a coherent transfer of mechanical excitation in a finely controlled artificial nanomechanical *** also realize strong dynamic coupling between adjacent high-Q mechanical resonators,via modulated dielectric force at the frequency difference between *** excitation transfer across a lattice consisting of 7 nanobeams is observed by applying a design sequence of switching for couplings,with the final effective population reaching *** work not only demonstrates the ability to fully control an artificial lattice but also provides an efficient platform for studying complicated dynamics in one-dimensional systems.

关键词： excitation coupling lattice

Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

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Science China Chemistry 2022年第2期65卷 298-303页

作者： tian-Ci Wang pu-Sheng Wang Dian-Feng Chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of CAS Hefei 230026China

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.

关键词： asymmetric catalysis palladium allylic C–H borylation allyl ethers chiral phosphoric acid aldehydes

Study and Application of Bottom Blowing Technique of Combined Blowing Converter

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Journal of Iron and Steel Research International 2014年第1期21卷 41-45页

作者： Li-bin YANG Liu LIU Xing-li jiao pu-qiao TONG Central Iron and Steel Research Institute No.4Steelmaking and Rolling General Plant Masteel

The water modelling experiments of 300 t converter concerning combined blowing parameters, the number, and configuration of bottom nozzles are carried out. The results show that the arrangement of 16 bottom nozzles at 0. 40D and 0. 45D （hearth diameter） concentric circles is the reasonable solution. The combined blowing steel- making technique of 300 t converter has been developed through experiments and studies relating to optimizing the top-bottom combined blowing pattern, the number and configuration of the bottom nozzles, the type selection of bot- tom nozzle, and bottom nozzle maintenance techniques. The results show that the product of w[c] ＂ w[o] at endpoint is reduced from 0. 002 62 to 0. 002 43, average TFe content is decreased by %, phosphorus distribution is raised from 70.85 to 78.95, sulfur distribution is raised from 3.43 to 4.32 and manganese content is raised by 0.02%.

关键词： combined blowing bottom nozzle maintenance technique water model product of carbon and oxygen

A Facile Synthesis of Squamosamide Cyclic Analogs

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Chinese Chemical Letters 2003年第7期14卷 667-669页

作者： Xiao Zhen jiao Ping XIE Xiao tian LIANG Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050

A series of novel cyclic derivatives have been synthesized by utilizing a nickel powder mediated radical cyclization as the key step. The structures of the new compounds were confirmed by 1H-NMR and MS.

关键词： Squamosamide radical cyclization synthesis.

Towards multi-party targeted model poisoning attacks against federated learning systems

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High-Confidence Computing 2021年第1期1卷 45-54页

作者： Zheyi Chen pu tian Weixian Liao Wei Yu Department of Computer and Information Sciences Towson UniversityMD 21252 USA

The federated learning framework builds a deep learning model collaboratively by a group of connected devices via only sharing local parameter updates to the central parameter ***,the lack of transparency in the local data resource makes it prone to adversarial federated attacks,which have shown increasing ability to reduce learning *** research efforts either focus on the single-party attack with impractical perfect knowledge setting and limited stealthy ability or the random attack that has no control on attack *** this paper,we investigate a new multi-party adversarial attack with the imperfect knowledge of the target *** by an adversary,a number of compromised devices collaboratively launch targeted model poisoning attacks,intending to misclassify the targeted samples while maintaining stealthy under different de-tection ***,the compromised devices jointly minimize the loss function of model training in different *** overcome the update scaling problem,we develop a new boosting strategy by introducing two stealthy *** experimental results,we show that under both perfect knowledge and limited knowl-edge settings,the multi-party attack is capable of successfully evading detection strategies while guaranteeing the *** also demonstrate that the learned model achieves the high accuracy on the targeted samples,which confirms the significant impact of the multi-party attack on federated learning systems.

关键词： Adversarial federated learning Perfect knowledge Limited knowledge Boosting strategy High-confidence computing

Recent area and ice volume change of Kangwure Glacier in the middle of Himalayas

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Chinese Science Bulletin 2010年第20期55卷 2088-2096页

作者： MA LingLong tian LiDe pu JianChen WANG PengLing Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sci- ences Beijing 100085 China Graduate University of the Chinese Academy of Science Beijing 100049 China National Key Laboratory of Cryospheric Science Chinese Academy of Sciences Lanzhou 730000 China National Climate Center China Meteorological Administration Beijing 100081 China

This paper calculated and evaluated the area and ice volume changes of Kangwure Glacier in ***,middle of Himalayas in the past 3 decades,based on the field survey of glacier boundary position by differential GPS and glacier depth by Ground Penetrating Radar(GPR),together with the topographic map and remote sense *** studied data showed that the Kangwure Glacier has experienced significant mass deficit since the 1970s,with 34.2%of area loss,48.2%ofice volume loss and 7.5 m of average thickness *** result revealed that the ice volume loss of Himalayan glaciers was more serious than *** of meteorological data from two weather stations in the region of ***,shows that the air temperature of this region has risen from the middle of the 20th century to the beginning of the 21st *** retreat of Himalayas glacier driven by climatic warming will have a remarkable impact on hydrology and ecosystem.

关键词：喜马拉雅山冰川变化冰川面积冰量差分GPS 地质雷达探地雷达遥感数据

黄芩苷与苦参碱分子间相互作用的量子化学计算与验证

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原子与分子物理学报 2025年第4期42卷 8-14页

作者：董志舒启江田爽王皎侯安国王文苹云南中医药大学中药学院云南省南药可持续利用重点实验室昆明650500

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄... 详细信息

为探究苦参碱能极大增强黄芩苷在水中的溶解度的原因,采用量子计算对二者反应过程及共存状态进行分析,并使用单晶衍射和红外图谱验证计算结果.本研究表明,黄芩苷和苦参碱并非简单的以非共价作用相结合,二者存在质子转移现象,反应生成黄芩苷阴离子和苦参碱阳离子,以静电作用为主导形成共无定型物,导致水溶性极大增加.

关键词：苦参碱黄芩苷质子转移离子共无定型物

A new type of ice formation zone found in the Himalayas

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Chinese Science Bulletin 1999年第5期44卷 469-474页

作者： Tandong Yao Jianchen pu Ninlian Wang Lide tian Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

Ice formation was studied on the Dasuopu Glacier located in the Mount Xixabangma (28°23’ N, 85°43’E) in the Himalayas. Snow pits and shallow ice cores are analyzed to reveal ice formation process. The results show that the ice formation process, or in other words, the process of densitification, on the col (7 000 m a.s.l. ) of the Dasuopu Glacier is a stable, slow and gradual process. The snow-ice transformation on the glacier is estimated to be 30—40 m below the surface. The temperature on the Dasuopu Glacier is very low (～ - 14℃ at 10 m) and similar to that in polar type ice cap. We,therefore, speculate that the process of snow-ice transformation is undertaken under snow pressure,and that there is a percolation zone on the Dasuopu Glacier. The high altitude of the col and monsoon snow fall accompnied by heavy cloud and high albedo favorite the percolation zone formation.

关键词： ice formation glacial accumulation Dasuopu Glacier.