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Construction and numerical tests of the multi-conservation difference scheme

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chinese Science Bulletin 2003年第10期48卷 1016-1020页

作者： wang bin & JI Zhongzhen LASG, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A difference scheme with four conservation properties for solving the spherical barotropic shallow water equations is constructed, based on a proper formulae of the equations and a skillful correction on the spatial difference parts of the semi-discrete equations with which the number of the conservation properties of these equations is increased from three to four. Numerical tests are included, and good results are achieved in this study.

关键词：多态守恒差分图解法动力系统正压浅水波方程大气系统数字模型

Control of fine particulate nitrate during severe winter haze in“2+26”cities

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Journal of Environmental sciences 2024年第2期136卷 261-269页

作者： Chuang qin Xiao Fu Tao wang Jian Gao Jiaqi wang institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Department of Civil and Environmental Engineering Hong Kong Polytechnic UniversityHong Kong 99907China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 10084China

The“2+26”cities,suffering the most severe winter haze pollution,have been the key region for air quality improvement in *** prominent nitrate pollution is one of the most challenging environmental issues in this region,necessitating development of an effective control ***,we use observations,and state-of-the-art model simulations with scenario analysis and process analysis to quantify the effectiveness of the future SO_(2)-NO_(X)-VOC-NH_(3) emission control on nitrate pollution mitigation in“2+26”*** on a serious winter haze episode,we find that limited NO_(X)emission reduction alone in the short-term period is a less effective choice than VOC or NH_3emission reduction alone to decrease nitrate concentrations,due to the accelerated NO_(X)-HNO_(3)conversion by atmospheric oxidants and the enhanced HNO_(3)to NO_(3)^(-)partition by ammonia,although deep NO_(X)emission reduction is essential in the long-term *** synergistic NH_(3) and VOC emission control is strongly recommended,which can counteract the adverse effects of nonlinear photochemistry and aerosol chemical feedback to decrease nitrate *** extra benefits will be reduced if the synergistic NH_(3) and VOC reduction is delayed,and thus reducing emission of multiple precursors is urgently required for the effective control of increasingly severe winter nitrate pollution in“2+26”cities.

关键词： Nitrate Winter haze pollution Emission reduction “2+26”cities

The relationship between short-range motion of atmosphere and ocean and conservative and nonconservative scheme

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Science Bulletin 2003年第10期48卷 999-1001页

作者： LIN Wantao, JI Zhongzhen & wang bin LASG,institute of atmospheric physics, chinese academy of sciences, beijing 100029, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Taking one-dimensional shallow water wave equation as an example, a comparative analysis on the computational stability related to the short-range motion of atmosphere and ocean is carried out for the conservative and nonconservative scheme, and it is pointed out that the computational stability of conservative scheme is absolutely different from that of the nonconservative scheme. The relationship between the short-range motion of atmosphere and ocean and the conservative and nonconservative scheme is further discussed. The constructed conservative scheme is proved to be stable by the numerical experiment for the short-range motion of atmosphere and ocean while the CTCS scheme is unstable. So that the conservative scheme for the solution of this kind of problem has more advantages.

关键词： short-range motion of atmosphere and ocean conservative scheme nonconservative scheme computational stability.

A generative adversarial network-based unified model integrating bias correction and downscaling for global SST

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atmospheric and Oceanic Science Letters 2024年第1期17卷 45-52页

作者： Shijin Yuan Xin Feng bin Mu Bo qin Xin wang Yuxuan Chen School of Software Engineering Tongji UniversityShanghaiChina

本文提出了一种基于生成对抗网络的全球海表面温度(sea surface temperature,SST)偏差订正及降尺度整合模型.该模型的生成器使用偏差订正模块将数值模式预测结果进行校正,再用可复用的共享降尺度模块将订正后的数据分辨率逐次提高.该模... 详细信息

本文提出了一种基于生成对抗网络的全球海表面温度(sea surface temperature,SST)偏差订正及降尺度整合模型.该模型的生成器使用偏差订正模块将数值模式预测结果进行校正,再用可复用的共享降尺度模块将订正后的数据分辨率逐次提高.该模型的判别器可鉴别偏差订正及降尺度结果的质量,以此为标准进行对抗训练。同时,在对抗损失函数中含有物理引导的动力学惩罚项以提高模型的性能.本研究基于分辨率为1°的GFDL SPEAR模式的SST预测结果,选择遥感系统(Remote Sensing System)的观测资料作为真值,面向月尺度ENSO与IOD事件以及天尺度海洋热浪事件开展了验证试验:模型在将分辨率提高到0.0625°×0.0625°的同时将预测误差减少约90.3%,突破了观测数据分辨率的限制,且与观测结果的结构相似性高达96.46%.

关键词：偏差订正降尺度海表面温度生成对抗网络物理引导的神经网络

A VGGNet-based correction for satellite altimetry-derived gravity anomalies to improve the accuracy of bathymetry to depths of 6500 m

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Acta Oceanologica Sinica 2024年第1期43卷 112-122页

作者： Xiaolun Chen Xiaowen Luo Ziyin Wu Xiaoming qin Jihong Shang Huajun Xu bin Li Mingwei wang Hongyang Wan Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Ocean College Zhejiang UniversityZhoushan 316021China Key Laboratory of Ocean Space Resources Management Technology Marine Academy of ZhejiangHangzhou 310012China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China School of Civil Engineering and Architectures Zhejiang University of Science and TechnologyHangzhou 310023China National Center for Archaeology Beijing 100013China

Understanding the topographic patterns of the seafloor is a very important part of understanding our *** the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey *** this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep *** apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more *** obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth *** choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the *** experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high *** standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent *** evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous ***,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results.

关键词： gravity anomaly bathymetry inversion VGGNet multibeam sonar satellite altimetry

Texture and Geochemistry of Multi-stage Hydrothermal Scheelite in the Mamupu Cu-Au-Mo(-W)Deposit,Eastern Tibet:Implications for Tungsten Mineralization in the Yulong Belt

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 701-716页

作者： ZHANG Xiaoxu TANG Juxing LIN bin wang qin HE Liang YAN Gang SHAO Rui WU Qiang DU Qiu ZHAXI Pingcuo Chengdu Center China Geological Survey(Geosciences Innovation Center of Southwest China)Chengdu 610081China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China Earth sciences College Chengdu University of TechnologyChengdu 610059China No.6 Geological Party Tibetan Bureau of Geology and Mineral Exploration and DevelopmentLhasa 851400China Tibet Shengyuan Mining Group Co. Ltd.Lhasa 851400China

Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),*** study reports the results of cathodoluminescence,trace element and Sr isotope analyses of Mamupu scheelite samples,undertaken in order to better constrain the mechanism of W mineralization and the sources of the ore-forming *** different types of scheelite are identified in the Mamupu deposit:scheelite A(Sch A)mainly occurs in breccias during the prograde stage,scheelite B(Sch B)forms in the chlorite-epidote alteration zone in the retrograde stage,while scheelite C(Sch C)occurs in distal quartz sulfide *** extremely high Mo content and negative Eu anomaly in Sch A represent high oxygen fugacity in the prograde *** with ore-related porphyries,Sch A has a similar REE pattern,but with higher ΣREE,more depleted HREE and slightly lower(^(87)Sr/^(86)Sr)i *** features suggest that Sch A is genetically related to ore-related porphyries,but extensive interaction with carbonate surrounding rocks affects the final REE and Sr isotopic *** B shows dark(Sch B-I)and light(Sch B-II)domains under CL *** Sch B-I to Sch B-II,LREEs are gradually depleted,with MREEs being gradually *** C has the highest LREE/HREE ratio,which indicates that it inherited the geochemical characteristics of fluids after the precipitation of HREE-rich minerals,such as diopside and garnet,in the early prograde *** Mo content in Sch B and Sch C gradually decreased,indicating that the oxygen fugacity of the fluids changed from oxidative in the early stages to reductive in the later,the turbulent Eu anomaly in Sch B and Sch C indicating that the Eu anomaly in the Mamupu scheelite is not solely controlled by oxygen *** extensive interaction of magmatic-hydrothermal fluids and carbonate provides the necessary Ca^(2+)for the precipitation of scheelite in the Mamupu deposit.

关键词： scheelite geochemistry Mamupu Cu deposit Yulong porphyry copper belt eastern Tibet

Boosting synergism of chemo- and immunotherapies via switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis by bisphosphonate coordination lipid nanogranules

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Acta Pharmaceutica Sinica B 2024年第2期14卷 836-853页

作者： Ge Song Minghui Li Shumin Fan Mengmeng qin bin Shao Wenbing Dai Hua Zhang Xueqing wang bing He Qiang Zhang beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems School of Pharmaceutical SciencesPeking UniversityBeijing 100191China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Department of Medical Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Peking University Cancer HospitalBeijing 100142China

Conventional chemotherapy based on cytotoxic drugs is facing tough challenges recently following the advances of monoclonal antibodies and molecularly targeted *** is critical to inspire new potential to remodel the value of this classical therapeutic ***,we fabricate bisphosphonate coordination lipid nanogranules(BC-LNPs)and load paclitaxel(PTX)to boost the chemo-and immuno-therapeutic synergism of cytotoxic *** in BC-LNPs@PTX,a bisphosphonate to block mevalonate metabolism,works as both the structure and drug constituent in nanogranules,where alendronate coordinated with calcium ions to form the particle *** synergy of alendronate enhances the efficacy of paclitaxel,suppresses tumor metastasis,and alters the cytotoxic *** from the paclitaxel-induced apoptosis,the involvement of alendronate inhibits the mevalonate metabolism,changes the mitochondrial morphology,disturbs the redox homeostasis,and causes theaccumulation of mitochondrial ROS and lethal lipid peroxides(LPO).These factors finally trigger the ferroptosis of tumor cells,an immunogenic cell death mode,which remodels the suppressive tumor immune microenvironment and synergizes with ***,by switching paclitaxel-induced apoptosis to mevalonate metabolism-triggered ferroptosis,BC-LNPs@PTX provides new insight into the development of cytotoxic drugs and highlights the potential of metabolism regulation in cancer therapy.

关键词： Bisphosphonate coordinationlipid nanogranules Ferroptosis Mevalonatemetabolism Mitochondrial metabolism Nano-systematic biology

A deep learning-based global tropical cyclogenesis prediction model and its interpretability analysis

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Science china Earth sciences 2024年

作者： bin MU Xin wang Shijin YUAN Yuxuan CHEN Guansong wang Bo qin Guanbo ZHOU School of Software Engineering Tongji University Department of atmospheric and Oceanic sciences & institute of atmospheric sciences Fudan University National Meteorological Center Shanghai Typhoon institute China Meteorological Administration

Tropical cloud clusters (TCCs) can potentially develop into tropical cyclones (TCs),leading to significant casualties and economic *** prediction of tropical cyclogenesis (TCG) is crucial for early *** traditional deep learning methods applied to TCG prediction rely on predictors from a single time point,neglect the ocean-atmosphere interactions,and exhibit low model *** study proposes the Tropical Cyclogenesis Prediction-Net (TCGP-Net) based on the Swin Transformer,which leverages convolutional operations and attention mechanisms to encode spatiotemporal features and capture the temporal evolution of *** model incorporates the coupled ocean-atmosphere interactions,including multiple variables such as sea surface ***,causal inference and integrated gradients are employed to validate the effectiveness of the predictors and provide an interpretability analysis of the model’s decision-making *** model is trained using GridSat satellite data and ERA5 reanalysis *** results demonstrate that TCGP-Net achieves high accuracy and stability,with a detection rate of 97.9%and a false alarm rate of 2.2%for predicting TCG 24 hours in advance,significantly outperforming existing *** indicates that TCGP-Net is a reliable tool for tropical cyclogenesis prediction.

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Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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china Communications 2024年第5期21卷 77-96页

作者： Zhao Di Zheng Zhong qin Pengfei qin Hao Song bin State Key Laboratory of Integrated Services Networks Xidian University710071China china academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing *** this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user *** first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)***,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource *** results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness