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Combining Monte Carlo and Ensemble Probabilities in Tropical Cyclone Forecasts near Landfall

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Journal of Meteorological Research 2021年第4期35卷 607-622页

作者： Xin li Zhaoxia pu Zhiqiu GAO Department of Atmospheric Sciences University of UtahSalt Lake CityUT S4A VIUSA Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

The Monte Carlo probability(MCP)model,which has been used for official tropical cyclone(TC)warnings to the public by the United States’National Hurricane Center(NHC),can estimate the probability of wind speed in the vicinity of a TC during the forecast *** has been successful in the operational environment for many ***,due to its strong dependence on a given forecast track(e.g.,forecast from the NCEP Global Forecast System),the MCP model may generate a poor probability map for TCs near *** this study,we proposed and tested a modified MCP method for TC forecasts near *** first adjusted the MCP model by adding limits to the direction angle and motion distance to deal with the substantial change in TC moving direction and the low wind speeds during ***,we combined ensemble probability maps generated from ECMWF,United Kingdom Met Office(UKMO),and NCEP ensemble forecasts,obtained from The International Grand Global Ensemble(TIGGE),into the MCP model to configure a modified MCP *** speed probability maps for the 0-120-h forecast from both the original and modified MCP models are *** is found that the modified MCP model can provide a better wind speed probability map during landfall,especially at wind speeds of 20-64 kt near TC *** results from this study prove the benefits of combining the MCP model with ensemble forecasting in potential applications for improved TC forecasts.

关键词： tropical cyclone Monte Carlo model ensemble forecasting wind speed probability

Trailing (L5) Neptune Trojans: 2004 KV18 and 2008 LC18

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Research in Astronomy and Astrophysics 2012年第11期12卷 1549-1562页

作者： pu Guan li-Yong Zhou jian li Department of Astronomy & Key Laboratory of Modem Astronomy and Astrophysics in Ministryof Education Nanjing University Nanjing 210093 China

The population of Neptune Trojans is believed to be bigger than that of Jupiter Trojans and that of asteroids in the main belt, although only eight members of this distant asteroid swarm have been observed up to now. Six leading Neptune Trojans around the Lagrange point L4 discovered earlier have been studied in detail, but two trailing ones found recently around the L5 point, 2004 KV18 and 2008 LC18, have not yet been investigated. We report our investigations on the dynamical behaviors of these two new Neptune Trojans. Our calculations show that the asteroid 2004 KV18 is a temporary Neptune Trojan. Most probably, it was captured into the trailing Trojan cloud no earlier than 2.03 ×105 yr ago, and it will not maintain this position later than 1.65 × 105 yr in the future. Based on the statistics from our orbital simulations, we ar- gue that this object is more like a scattered Kuiper belt object. By contrast, the orbit of 2008 LC18 is much more stable. Among the clone orbits spreading within the orbital uncertainties, a considerable portion of clones may survive on the L5 tadpole orbits for 4 Gyr. The strong dependence of the stability on the semimajor axis and resonant angle suggests that further observations are badly required to constrain the orbit in the stable region. We also discuss the implications of the existence and dynamics of these two trailing Trojans over the history of the solar system.

关键词： solar system general -- Kuiper belt -- asteroids -- methods numerical

Load Shedding Control Strategy in Power Grid Emergency State Based on Deep Reinforcement Learning

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1175-1182页

作者： jian li Sheng Chen Xinying Wang Tianjiao pu China Electric Power Research Institute Haidian DistrictBeijing 100192China

In viewing the power grid for large-scale new energy integration and power electrification of power grid equipment,the impact of power system faults is increased,and the ability of anti-disturbance is decreased,which makes the power system fault clearance more *** this paper,a load shedding control strategy based on artificial intelligence is proposed,this action strategy of load shedding,which is selected by deep reinforcement learning,can support autonomous voltage ***,the power system operation data is used as the basic data to construct the network training dataset,and then a novel reward function for voltage is *** value function,which conforms to the power grid operation characteristics,will act as the reward value for deep reinforcement learning,and the Deep Deterministic Policy Gradient algorithm(DDPG)algorithm,with the continuous action strategy,will be ***,the deep reinforcement learning network is continuously trained,and the load shedding strategy concerning the grid voltage control problem will be obtained in the power system emergency control situation,and this strategy action is input into the Pypower module for simulation verification,thereby realizing the joint drive of data and *** to the numerical simulation analysis,it shows that this method can effectively determine the accurate action selection of load shedding,and improve the stable operational ability of the power system.

关键词： Artificial intelligence deep reinforcement learning load shedding control power system emergency state

Industrial Production of Catalyst for Removing Trace Olefins from Aromatics

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China Petroleum Processing & Petrochemical Technology 2012年第2期14卷 44-49页

作者： pu Xin Shi li The State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237

A novel additive incorporated into the catalyst for removing trace olefins from aromatics was proposed, and under the laboratory conditions the lifetime of the catalyst was increased from 5 h to 8 h upon specifying the conversion of the olefins equating to more than 55% as a criterion. Catalyst production, which was named ROC, has been successfully scaled up from laboratory formulations to commercial scale manufacture and over 100 tons of catalyst had been produced. The superiority in catalytic activity was identified by the evaluation tests of the ROC catalyst based on whatever kind of feedstocks (with their bromine index ranging from 400 mgBr/100g to 1 200 mgBr/100g) being used as the feedstock. The X-ray diffraction patterns had verified that the additive was highly dispersed on the surface of catalyst; the GC-FID analysis results showed that the ROC catalyst could increase the xylene content; the pyridine-FTIR spectroscopic analyses suggested that the additive could increase the amount of the weak L acids, which was the main cause leading to enhancement of the catalyst activity.

关键词： olefins aromatics industrial production catalyst

Cotilting modules with finite left perpendicular categories Dedicated to Professor Feng Keqin on the Occasion of his 70th Birthday

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Science China Mathematics 2012年第1期55卷 93-98页

作者： li ZhiWei ZHANG pu Department of Mathematics Shanghai Jiao Tong UniversityShanghai 200240China

We characterize a cotilting module T such that the left perpendicular category ⊥ T is of finite type.

关键词： cotilting module resolving module finite type

Loading necrostatin-1 composite bone cement inhibits necroptosis of bone tissue in rabbit

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Regenerative Biomaterials 2019年第2期6卷 113-119页

作者： Xiang Ji Feng Xu Guoling Dong Chongzhe jia pu jia Hao Chen Hai Tang Department of Orthopedics Beijing Friendship HospitalCapital Medical UniversityNo.95Yong’an RoadXicheng DistrictBeijing 100050China

Bone necrosis after injecting of polymethylmethacrylate(PMMA)bone cement will lead to re-fracture of bone *** a new type of necrosis,there is little research related to the necroptosis of surrounding bone tissue near the bone *** purpose of our study was to(i)investigate the presence of necroptosis in vivo and,(ii)established as a new type of bone cement containing PMMA,calcium phosphate cement(CPC)and Necrostatin-1(Nec-1)to inhibit necroptosis of bone tissue.A total of 12 Japanese rabbits were used to establish the animal model and randomly divided into 4 groups signed as a control group,PMMA group,PMMA–CPC group and PMMA–CPC–Nec-1 group,*** used scanning electron microscope to observe the structure of the samples,used HE staining to detect the necrosis,and used western blotting as well as EliSA test to examine the iconic molecule receptor interacting protein kinase-3(RIP 3)protein and tumor necrosis factor a(TNF-a).After analyzing the results of our study,we found that the structure in both PMMA bone cement group and composite bone cement group was damaged and there was an evidence of necrosis,but it was absent in control *** molecule detection,the RIP 3 protein expression was decreased in PMMA–CPC–Nec-1(P<0.05).TNF-a expression was increased in bone cement groups with and without CPC(P<0.05),but was inhibited in PMMA–CPC–Nec-1 *** have concluded that the necroptosis could be confirmed in bone tissue necrosis induced by TNF-a after bone cement injection and also could be inhibited by composite bone cement with Nec-1.

关键词： necrostatin-1 necroptosis composite bone cement

REFLECTION AND TRANSMISSION OF OBliQUELY INCIDENT RAYLEIGH SURFACE WAVES BY A VISCOELASTIC INTERPHASE

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Acta Mechanica Solida Sinica 1998年第3期11卷 229-240页

作者： li Zailiang Gong pu Beijing Univ Aeronaut & Astronaut Inst Solid Mech Beijing 100083 Peoples R China Huazhong Univ Sci & Technol Dept Mech Wuhan 430074 Peoples R China

The reflection and transmission of obliquely incident Rayleighsurface waves by an in- terphase between two quarter spaces ofidentical or different materials, have been investigated. Themechanical behavior of the interphase is represented by a thinviscoelastic layer. By using the full space Green's functions due toa spatially harmonic line load, the mathematical statement of the3-dimen- sion problem is reduced to a 2-dimension system of singularintegral equations. The far-field behavior of the scattered wavesleads to the definition of reflection and transmission coefficients,R and T.

关键词： Rayleigh surface waves interphase reflection and transmissioncoefficients

Betaine addition to the diet alleviates intestinal injury in growing rabbits during the summer heat through the AAT/mTOR pathway

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1623-1637页

作者： Zimei li Junning pu Xiang Chen Yanbin Chen Xiaoyan Peng Jingyi Cai Gang jia Hua Zhao Gang Tian Animal Nutrition Institute Sichuan Agricultural UniversityChengduSichuan 611130China

Background The aim of this experiment was to investigate the effect of different levels of betaine(Bet)inclusion in the diet on the intestinal health of growing rabbits under summer heat.A total of 100 weaned Qixing meat rabbits aged 35 d with body weight of 748.61±38.59 g were randomly divided into 5 treatment groups:control group(basal diet)and Bet groups(basal diet+0.75,1.0,1.5 or 2.0 g/kg Bet).The average daily temperature in the rabbitry during the experiment was 30.48°C and the relative humidity was 69.44%.Results Dietary addition of Bet had no significant effect on growth performance and health status of growing rabbits(P>0.05),but it increased ileal secretory immunoglobulin A content compared to the control under summer heat(Pli height(VH)in the jejunum(P<0.05).Serum glucose levels were reduced,and the expression of SLC6A20 was up-regulated in jejunum and ileum of rabbits fed with 1.5 g/kg Bet(P<0.05).When added at 2.0 g/kg,Bet reduced serum HSP70 content,increased jejunal VH,and up-regulated duodenal SLC7A6,SLC38A2,mTOR and 4EBP-2 expression(P<0.05).Correlation analysis revealed that intestinal mTOR expression was significantly and positively correlated with SLC7A6,SLC38A2,SLC36A1 and IL-4 expression(P<0.05).Conclusions Dietary addition of Bet can up-regulate the expression of anti-inflammatory factors through the AAT/mTOR pathway,improve the intestinal immune function,alleviate intestinal damage in growing rabbits caused by summer heat,and improve intestinal health.

关键词： AAT/mTOR Betaine Growing rabbits Intestinal injury Summer heat

A review on novel activation strategy on carbonaceous materials with special morphology/texture for electrochemical storage

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Journal of Energy Chemistry 2021年第9期30卷 572-590页

作者： Yueming li Ziyan pu Qimeng Sun Ning Pan State Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004HebeiChina Biological&Agricultural Engineering University of California DavisCA95616USA

Various novel carbonaceous materials including carbon nanotubes,nano-onions,carbon microspheres,graphene nanosheets,and carbon microfibers with unique properties,such as tunable surface area and pore size,high chemical stability,cost-effective and facile preparation,have attracted enormous interest for many *** essential,the activation processes play a critical role to achieve these valuable *** this review,we provide a thorough analysis of the emerging nano-and microscopic carbon species with special morphology/textures and currently available types of chemical activation agents,and novel activation strategy to enhance electrochemical performance of activated carbon material in electrical energy storage devices including supercapacitor and alkaline ions batteries.A particular emphasis is set on recent advance in activated carbon materials with special morphology/textures for supercapacitors and sodium ion batteries.

关键词： Carbonaceous materials Special morphology/texture Chemical activation Doping Supercapacitor Rechargeable batteries Sodium ion batteries