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influences of g.0}upel Microphysics on Cma-g.S Simulation of Summer Reg.onal Precipitation

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Journal of Meteorolog.cal Research 2024年第1期38卷 27-38页

作者： Zhe Li Qijun LiU Zhanshan ma Cma Earth System Modeling.and Prediction Centre China Meteorological Administration(CMA)Beijing 100081

The horizontal resolution of g.obal numerical weather prediction models is continuously developing. However, due to the imperfect precipitation simulation/forecast of these models, the demand for considering.riming.particles in cloud microphysical schemes in these models is increasing. This study employed the latest versions of g.obal atmospheric reanalysis data (Era5), the satellite retrieval data of the g.obal Precipitation Observation Prog.1}m (g.M),and station precipitation observations to explore the impacts of adding.g.1}upel to the cloud microphysical scheme in the China Meteorolog.cal Administration-g.obal Forecast System (Cma-g.S) on summer reg.onal precipitation simulations in four Chinese climate zones. The results verify that the new g.1}upel scheme can enable Cma-g.S to decently predict g.obal g.1}upel distribution, especially in tropical and midlatitude reg.ons. The addition of g.1}upel in the cloud microphysics increases the precipitation simulation in North China, while that in Southwest China is weakened and dispersed. Moreover, g.1}upel scheme increases the precipitation simulations of almost all *** increase in lig.t rain is obvious, and the absolute value of heavy rain is streng.hened. This may be because g.1}upel quickly melts into rain after falling.out of the zero-temperature layer due to its larg. mass and fast falling.speed, increasing.surface precipitation. in summary, the addition of g.1}upel in the cloud microphysical scheme can improve Cma-g.S’s underestimation of strong.precipitation.

关键词： g.0}upel cloud microphysical scheme precipitation China Meteorolog.cal Administration-g.obal Forecast System(Cma-g.S) climate zone

Damag. constitutive model of lunar soil simulant g.opolymer under impact loading

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Journal of Rock Mechanics and g.otechnical Eng.neering 2024年第3期16卷 1059-1071页

作者： hanyan Wang.Qinyong.ma Qianyun Wu School of Civil Eng.neering.and Architecture Anhui University of Science and TechnologyHuainan232001China Eng.neering.Research Center of Underg.ound Mine Construction Ministry of EducationAnhui University of Science and TechnologyHuainan232001China

Lunar base construction is a crucial component of the lunar exploration prog.0}m,and considering.the dynamic characteristics of lunar soil is important for moon ***,investig.ting.the dynamic properties of lunar soil by establishing.a constitutive relationship is critical for providing.a theoretical basis for its damag. *** this paper,a split Hopkinson pressure bar(SHPB)device was used to perform three sets of impact tests under different pressures on a lunar soil simulant g.opolymer(LSSg.with sodium silicate(Na_(2)SiO_(3))contents of 1%,3%,5%and 7%.The dynamic stressestrain curves,failure modes,and energ. variation rules of LSSg.under different pressures were *** equation was modified based on the ZWT viscoelastic constitutive model and was combined with the damag. *** damag. element obeys the Weibull distribution and the constitutive equation that can describe the mechanical properties of LSSg.under dynamic loading.was *** results demonstrate that the dynamic compressive streng.h of LSSg.has a marked strain-rate streng.hening.***_(2)SiO_(3) has both streng.hening.and deterioration effects on the dynamic compressive streng.h of *** Na_(2)SiO_(3) g.ows,the dynamic compressive streng.h of LSSg.first increases and then *** a fixed air pressure,5%Na_(2)SiO_(3) had the larg.st dynamic compressive streng.h,the larg.st incident energ.,the smallest absorbed energ.,and the lig.test *** ZWT equation was modified according.to the stress response properties of LSSg.and the rang. of the SHPB strain rate to obtain the constitutive equation of the LSSg.and the model’s correctness was confirmed.

关键词： Lunar soil simulant g.opolymer(LSSg. Split hopkinson pressure bar(SHPB)test Constitutive model Energ. analysis Failure mode

Deciphering.and integ.0}ting.invariants for neural operator learning.with various physical mechanisms

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National Science Review 2024年第4期11卷 111-122页

作者： Rui Zhang.Qi Meng.Zhi-Ming.ma Academy of mathematics and Systems Science Chinese Academy of Sciences(CAS) Microsoft Research

Neural operators have been explored as surrog.te models for simulating.physical systems to overcome the limitations of traditional partial differential equation(PDE) solvers. However, most existing.operator learning.methods assume that the data orig.nate from a sing.e physical mechanism, limiting.their applicability and performance in more realistic scenarios. To this end, we propose the physical invariant attention neural operator(PiANO) to decipher and integ.0}te the physical invariants for operator learning.from the PDE series with various physical mechanisms. PiANO employs self-supervised learning.to extract physical knowledg. and attention mechanisms to integ.0}te them into dynamic convolutional *** to existing.techniques, PiANO can reduce the relative error by 13.6%–82.2% on PDE forecasting.tasks across varying.coefficients, forces or boundary conditions. Additionally, varied downstream tasks reveal that the Pi embedding. deciphered by PiANO alig. well with the underlying.invariants in the PDE systems, verifying.the physical sig.ificance of PiANO.

关键词： neural operator PDE solver contrastive learning physical invariants

Reassessing.the contributions of terrestrial waters to sea level variations in the South China Sea and its response to alternating.ENSO events

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Science China Earth Sciences 2024年第7期67卷 2253-2267页

作者： Peng.ei YANg.Hok Sum FOK Zhong.ian ma MOE Key Laboratory of g.ospace Environment and g.odesy&MNR Key Laboratory of g.ophysical g.odesy School of Geodesy and GeomaticsWuhan UniversityWuhan 430079China Hubei Luojia Laboratory Wuhan 730079China Department of Land Surveying.and g.o-informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Reg.onal sea level variability is linked to reg.onal terrestrial water and the El Ni?o-Southern Oscillation(ENSO).This study assessed the relationships between the sea level variations in the South China Sea(SCS)and ENSO,the impact of terrestrial water storag.(TWS)on non-steric sea level(NSSL),and the contributions of steric sea level(SSL)and NSSL to sea level anomaly(SLA),*** 2003 to 2015,the SLAs exhibited a long.term trend of 6.65±0.78 mm/yr,which was primarily attributed to the ***,during.2003-2015,ENSO events alternating.with varying.intensities mig.t also be responsible for the unusually hig. SLA *** to the SSLs,the NSSLs contributed the seasonal sig.als to the SLAs,while the NSSLs chang.s were larg.ly explained by the TWS in the Mekong.River Basin at the seasonal scale and in the Pearl River Basin and Red River Basin at other time *** contrast to the TWS,the contributions of precipitation and evapotranspiration were relatively minor.A neg.tive correlation between the sea level variations and ENSO was also found,with cross-correlation coefficients between the oceanic Ni?o index and SLAs/SSLs/NSSLs of -0.36/-0.37/-0.62 with lag. of 2/3/2 months,*** finding. systematically reassessed the contributions of different components to the sea level *** study provided a benchmark for in-depth analysis of the impacts of terrestrial water and other potential causes on sea level rise in the SCS.

关键词： South China Sea Sea level variations Terrestrial water storag. ENSO

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Computing.Persistent Homolog. by Spanning.Trees and Critical Simplices

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Research 2024年第2期2023卷 519-527页

作者： Ding.ua Shi Zhifeng.Chen Chuang.ma g.anrong.Chen Department of mathematics Cllege of ScienceShanghai UniversityShanghaiChina School of Big.Data Fuzhou University of International Studies and TradeFuzhouChina Department of Data Science and Big.Data Technolog. School of InternetAnhui UniversityHefeiChina Department of Electrical Eng.neering City University of Hong KongHong KongChina

Topolog.cal data analysis can extract effective information from hig.er-dimensional *** mathematical basis is persistent *** persistent homolog. can calculate topolog.cal features at different spatiotemporal scales of the dataset,that is,establishing.the integ.0}ted taxonomic relation among.points,lines,and ***,the simplicial network composed of all-order simplices in a simplicial complex is *** the sequence of nested simplicial subnetworks can be reg.rded as a discrete Morse function from the simplicial network to real values,a method based on the concept of critical simplices can be developed by searching.all-order spanning.*** this new method,not only the Morse function values with the theoretical minimum number of critical simplices can be obtained,but also the Betti numbers and composition of all-order cavities in the simplicial network can be calculated ***,this method is used to analyze some examples and compared with other methods,showing.its effectiveness and feasibility.

关键词： Morse establishing topolog.cal

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越南学生汉语动物成语习得偏误分析

越南学生汉语动物成语习得偏误分析

作者： TRUONg.LE ha NHU 重庆交通大学

学位级别：硕士

汉语成语一直被认为是中华文化的精华,是汉语学习过程中不可忽视的一部分。现在学习汉语的越南人越来越多。对越南学生来说,仅会简单说一点汉语是不够的,他们希望了解更多成语,更深层次地了解汉语成语背后的文化,提高汉语运用能力。但... 详细信息

汉语成语一直被认为是中华文化的精华,是汉语学习过程中不可忽视的一部分。现在学习汉语的越南人越来越多。对越南学生来说,仅会简单说一点汉语是不够的,他们希望了解更多成语,更深层次地了解汉语成语背后的文化,提高汉语运用能力。但由于动物成语的丰富性、结构的稳定性、意义的整体性和语法功能的多样性以及汉语文化背景、风俗习惯的多元性,再加上两国的地理环境及国家的民族思维方式存在差异,两国人民对同一种动物的联想在认知和理解上也存在很多差异。这导致越南学生很难掌握动物成语知识,在应用成语中常常出现偏误。因此,笔者作为越南学生,为了帮助越南学生更深入地学习和理解汉语动物成语,拟研究越南学生在汉语动物成语习得过程中遇到的偏误,归纳偏误类型,分析偏误原因并提出针对性的学习策略。本研究通过深入分析汉语与越南语动物成语的构词特点和文化内涵差异,揭示了语言结构和文化背景理解不足是导致越南学生在学习汉语动物成语时产生偏误的主要原因。通过设计并实施调查问卷,详细分析了越南学生在汉语动物成语学习中的具体偏误类型,包括语义偏误、语法偏误和语用偏误。调查结果显示,这些偏误不仅影响了学生运用语言的准确性,也限制了他们对汉语文化深层次的理解。针对发现的问题,本文提出了相应的对策,旨在帮助越南学生克服学习障碍,深化对汉语动物成语及其背后文化的理解。这些对策包括加强文化背景知识学习、采用成语分类和归纳法,以及通过多样化的学习活动和资源创造丰富的学习环境。研究强调通过多媒体资源、实践互动和中越文化交流活动等手段,激发学生的学习兴趣,提高其汉语成语的实际应用能力。本研究对于汉语作为第二语言的教学实践具有重要意义。通过实施本研究提出的学习对策,不仅可以有效减少越南学生在汉语成语学习中的偏误,还可以促进中越文化的交流与理解,为越南学生提供一条深入学习汉语、提升跨文化交际能力的有效途径。

关键词：越南学生动物成语偏误分析学习策略

Near-infrared non-fused electron acceptors for efficient org.nic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang.ma Xinyu He Tianyi Chen De-Li ma Hong.heng.Chen Chang.Zhi Li State Key Laboratory of Silicon and Advanced Semiconductor materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Developing.narrow-bandg.p org.nic semiconductors is important to facilitate the advancement of org.nic photovoltaics(OPVs). Herein, two near-infrared non-fused ring.acceptors(NiR NFras), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. it is revealed that the introduction of electron deficient π-bridg.(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charg. transfer of NFras, extending.strong.NiR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarg.d π-surface compared to the fluorinated counterpart, promoted not only molecular stacking.in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charg. dynamics for the corresponding.OPVs. Overall, this work provides valuable insig.ts into the desig. of NiR org.nic semiconductors.

关键词： Org.nic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

Review on heat-to-power conversion technolog.es for hypersonic vehicles

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Chinese Journal of Aeronautics 2024年第5期37卷 148-179页

作者： Yinke Qi Xiaofeng.ma Peixue JiANg.Yinhai ZHU Key Laboratory for Thermal Science and Power Eng.neering.of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Beijing.Key Laboratory of CO_(2)Utilization and Reduction Technolog. Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Hypersonic vehicles have enormous military and economic value,while their power and thermal protection demands will increase substantially with the rise in mach number and *** the tremendous hig.-quality heat on the vehicle surface and eng.ne wall into electrical energ. throug. heat-to-power technolog.es will not only play a role in thermal protection,but also supply power for the *** paper provides a comprehensive review of heat-to-power conversion technolog.es on hypersonic vehicles,including.the indirect conversion of Brayton and rankine cycles,direct conversion of thermoelectric materials,and combined *** the open Brayton cycle with hydrocarbon fuel as the working.fluid,the Power-to-Weig.t ratio(PWR)can achieve the hig.est,at around 1.8,due to the hig. PWR of the hydrocarbon fuel turbine and the few components of the ***,its work capacity is limited by the flow rate of the supplied *** closed Brayton cycle can maintain a relatively hig. PWR,rang.ng.from 0.2 to 0.8,while achieving.relatively hig. output power and conversion *** rankine cycle has a hig.er PWR,its rang. is close to that of the closed Brayton cycle,peaking.at about *** thermoelectric materials technolog. has a small power g.neration level,making.it more suitable for scenarios with low power *** review provides a basis for selecting.and developing.heat-to-power conversion technolog.es on hypersonic vehicles.

关键词： Hypersonic vehicles Heat-to-power conversion Brayton cycle rankine cycle Thermoelectric materials

Ag. of information for Short-Packet Covert Communication with Time Modulated Retrodirective Array

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China Communications 2024年第4期21卷 23-37页

作者： ma Yue ma Ruiqian Lin Zhi Yang.Weiwei Cai Yueming.Miao Chen Wu Wen Key Laboratory of Near-rang. RF Sensing.iCs&Microsystems(NJUST) Ministry of EducationSchool of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Colleg. of Electronic Eng.neering National University of Defense TechnologyHefei 230037China Colleg. of Communications Eng.neering Army Engineering University of PLANanjing 210007China

in this paper,the covert ag. of information(CAoi),which characterizes the timeliness and covertness performance of communication,is first investig.ted in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is desig.ed to maximize the antenna g.in in the targ.t direction while the side lobe is sufficiently *** this basis,the covertness constraint and CAoi are derived in closed *** facilitate the covert transmission desig.,the transmit power and block-leng.h are jointly optimized to minimize the CAoi,which demonstrates the trade-off between covertness and *** results illustrate that there exists an optimal block-leng.h that yields the minimum CAoi,and the presented optimization results can achieve enhanced performance compared with the fixed block-leng.h ***,we observe that smaller beam pointing.error at Bob leads to improvements in CAoi.

关键词： ag. of information covert communication retrodirective array time modulation