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Advances in Atmospheric Sciences 2021年第12期38卷 2010-2022,I0002-I0008页

作者： Robin T.CLARK Peili WU Lixia ZHANG Chaofan LI Met Office Hadley Centre FitzRoy RoadExeter EX13PBUK LASG Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Highly unusual amounts of rainfall were seen in the 2020 summer in many parts of China,Japan,and South Korea.At the intercontinental scale,case studies have attributed this exceptional event to a displacement of the climatological western North Pacific subtropical anticyclone,potentially associated Indian Ocean sea surface temperature patterns and a mid-latitude wave train emanating from the North Atlantic.Using clusters of spatial patterns of sea level pressure,we show that an unprecedented 80%of the 2020 summer days in East Asia were dominated by clusters of surface pressure greater than normal over the South China Sea.By examining the rainfall and water vapor fluxes in other years when these clusters were also prevalent,we find that the frequency of these types of clusters was likely to have been largely responsible for the unusual rainfall of 2020.From two ensembles of future climate projections,we show that summers like 2020 in East Asia may become more frequent and considerably wetter in a warmer world with an enhanced moisture supply.

关键词： circulation clustering mei-yu front 2020 summer rainfall climate projections

Representation of the ENSO Combination Mode and its Asymmetric SST Response in Different Resolutions of HadGEM3

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Advances in Atmospheric Sciences 2018年第8期35卷 167-180页

作者： Jianghua WAN Hongli REN Peili WU Laboratory for Climate Studies and CMA-NJU Joint Laboratory for Climate Prediction Studies National Climate Center China Meteorological Administration Beijing 100081 China Department of Atmospheric Sciences School of Environment Studies University of Geoscience Wuhan 430074 China Met Office Hadley Center Exeter EX1 3PB UK

Previous studies have revealed a combination mode （C-mode） occurring in the Indo-Pacific region, arising from nonlinear interactions between ENSO and the western Pacific warm pool annual cycle. This paper evaluates the simulation of this C-mode and its asymmetric SST response in HadGEM3 and its resolution sensitivity using three sets of simulations at horizontal resolutions of N96, N216 and N512. The results show that HadGEM3 can capture well the spatial pattern of the C-mode associated surface wind anomalies, as well as the asymmetric response of SST in the tropical Pacific, but it strongly overestimates the explained variability of the C-mode compared to the ENSO mode. The model with the three resolutions is able to reproduce the distinct spectral peaks of the C-mode at the near annual combination frequencies, but the performance in simulating the longer periods is not satisfactory, presumably due to the unrealistic simulation of the ENSO mode. Increasing the horizontal resolution can improve the consistency between atmospheric and oceanic representations of the C-mode, but not necessarily enhance the accuracy of C-mode simulation compared with observation.

关键词： ENSO combination mode asymmetric response Nifio-A index HadGEM3 horizontal resolution

Assessing Global Warming Induced Changes in Summer Rainfall Variability over Eastern China Using the Latest Hadley Centre Climate Model HadGEM3-GC2

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Advances in Atmospheric Sciences 2018年第8期35卷 181-197页

作者： Yawen DUAN Peili WU Xiaolong CHEN Zhuguo MA Key Laboratory of Regional Climate-Environment Research for Temperate East Asia (TEA) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Met Office Hadley Centre Exeter EX1 3PB UK State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Summer precipitation anomalies over eastern China axe characterized spatially by meridionally banded structnres fluctu- ating on interannual and interdecadal timescales, leading to regional droughts and floods. In addition to long-term trends, how these patterns may change under global warming has important implications for agricultural planning and water resources over this densely populated area. Using the latest Hadley Centre climate model, HadGEM3-GC2, this paper investigates the potential response of summer precipitation patterns over this region, by comparing the leading modes between a 4×CQ simulation and the model＇s pre-industrial control simulation. Empirical Orthogonal Function （EOF） analyses show that the first two leading modes account for about 20% of summer rainfall variability. EOF1 is a monopole mode associated with the developing phase of ENSO events and EOF2 is a dipole mode associated with the decaying phase of ENSO. Under 4×CO2 forcing, the dipole mode with a south-north orientation becomes dominant because of a strengthened influence from exces- sive warming of the Indian Ocean. On interdecadal time scales, the first EOF looks very different from the control simulation, showing a dipole mode of east-west contrast with enhanced influence from high latitudes.

关键词： rainfall variability global warming ENSO HadGEM3-GC2

Increasing Flash Floods in a Drying Climate over Southwest China

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Advances in Atmospheric Sciences 2018年第8期35卷 198-203页

作者： Chan XIAO Peili WU Lixia ZHANG Robin T. CLARK National Climate Centre China Meteorological Administration Beijing 100081 China Met Office Hadley Centre FitzRoy Road Exeter EX1 3PB UK Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In a globally warming world, subtropical regions are generally expected to become drier while the tropics and mid-high latitudes become wetter. In line with this, Southwest China, close to 25°N, is expected to become increasingly prone to drought if annual mean precipitation decreases. However, despite this trend, changes in the temporal distribution of moisture supply might actually result in increased extreme rainfall in the region, whose climate is characterized by distinct dry and wet seasons. Using hourly and daily gauge observations, rainfall intensity changes since 1971 are exalnined for a network of 142 locations in the region. From the analysis, dry season changes are negligible but wet season changes exhibit a significantly strong downward trend [-2.4% （10 yr）^-1], particularly during the past 15 years [-17.7% （10 yr）^-1]. However, the intensity of events during the wettest of 5% hours appears to steadily increase during the whole period [1.4% （10 yr）^-1], tying in with government statistical reports of recent droughts and flooding. If the opposing trends are a consequence of a warming climate, it is reasonable to expect the contradictory trend to continue with an enhanced risk of flash flooding in coming decades in the region concerned.

关键词： regional water cycle flash floods drought Southwest China

Effect of Horizontal Resolution on the Representation of the Global Monsoon Annual Cycle in AGCMs

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Advances in Atmospheric Sciences 2018年第8期35卷 107-124页

作者： Lixia ZHANG Tianjun ZHOU Nicholas P.KLINGAMAN Peili WU Malcolm ROBERTS LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China National Centre for Atmospheric Science and Department of Meteorology University of ReadingReading RG6 6BBUnited Kingdom Met Office Hadley Centre ExeterEX1 3PBUnited Kingdom

The sensitivity of the representation of the global monsoon annual cycle to horizontal resolution is compared in three AGCMs： the Met Office Unified Model-Global Atmosphere 3.0; the Meteorological Research Institute AGCM3; and the Global High Resolution AGCM from the Geophysical Fluid Dynamics Laboratory. For each model, we use two horizon- tal resolution configurations for the period 1998-2008. Increasing resolution consistently improves simulated precipitation and low-level circulation of the annual mean and the first two annual cycle modes, as measured by the pattern correla- tion coefficient and equitable threat score. Improvements in simulating the summer monsoon onset and withdrawal are region-dependent. No consistent response to resolution is found in simulating summer monsoon retreat. Regionally, in- creased resolution reduces the positive bias in simulated annual mean precipitation, the two annual-cycle modes over the West African monsoon and Northwestern Pacific monsoon. An overestimation of the solstitial mode and an underestimation of the equinoctial asymmetric mode of the East Asian monsoon axe reduced in all high-resolution configurations. Systematic errors exist in lower-resolution models for simulating the onset and withdrawal of the summer monsoon. Higher resolution models consistently improve the early summer monsoon onset over East Asia and West Africa, but substantial differences exist in the responses over the Indian monsoon region, where biases differ across the three low-resolution AGCMs. This study demonstrates the importance of a multi-model comparison when examining the added value of resolution and the importance of model physical parameterizations for simulation of the Indian monsoon.

关键词： global monsoon high resolution modeling monsoon annual cycle AMIP

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基于异云融合架构的云培训平台

计算机应用与软件 2024年第5期41卷 345-349页

作者：吴佩莉兰州文理学院甘肃兰州730030

适应时代发展趋势的云培训为众多用户培训提供了出色的解决方案,呈现出不同行业的培训向云培训转移的契机。然而,现有服务型云培训平台大多难以契合不同行业的工作特质。针对企业培训的私属特性及其教学培训的闭环特性,吸取现有云培训... 详细信息

适应时代发展趋势的云培训为众多用户培训提供了出色的解决方案,呈现出不同行业的培训向云培训转移的契机。然而,现有服务型云培训平台大多难以契合不同行业的工作特质。针对企业培训的私属特性及其教学培训的闭环特性,吸取现有云培训技术的优点,突破传统培训模式,提出基于异云融合架构的云培训平台(C2TP),不仅解决了企业在线培训应用的“私属性”及现场培训需求的“开放性”矛盾,还进一步解决了培训中海量数据的传输技术、缓存技术及其安全性等问题。通过运行和测试表明,C2TP整体性能平稳,契合企业培训需求,实际使用中能较大提升企业培训的效率。

关键词：公共云私有云云培训平台

Deformation characteristics and damage ontologies of soft and hard composite rock masses under impact loading

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Journal of Mountain Science 2024年第5期21卷 1715-1727页

作者： LI Jinhua ZHANG Tianyu wu Baolin SU peili YANG Yang WANG Pan Architectural and Civil Engineering College Xi’an University of Science and TechnologyXi’an 710054China

As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study the dynamic properties of soft and hard composite rocks with different thickness ratios, this paper utilizes cement, quartz sand and gypsum powder to construct soft and hard composite rock specimens and utilizes a combination of indoor tests, numerical calculations, and theoretical analyses to investigate the mechanical properties of soft and hard composite rock bodies. The test results reveal that:(1) When the proportion of hard rock increases from 20% to 50%, the strength of the combined rock body increases by 69.14 MPa and 87 MPa when the hard rock face and soft rock face are loaded, respectively;however, when the proportion of hard rock is the same, the compressive strength of the hard rock face impact is 9%-17% greater than that of the soft rock face impact;(2) When a specimen of soft and hard combined rock body is subjected to impact loading, the damage mode involves mixed tension and shear damage, and the cracks generally first appear at the ends of the specimen, then develop on the laminar surface from the impact surface, and finally end in the overall damage of the soft rock part. The development rate and the total number of cracks in the same specimen when the hard rock face is impacted are significantly greater than those when the soft rock face is impacted;(3) By introducing Weibull’s statistical strength theory to establish the damage variables of soft-hard combined rock bodies, combined with the DP strength criterion, the damage model and the Kelvin body are concatenated to obtain a statistical damage constitutive model, which can better fit the full stress-strain curve of soft-hard combined rock body specimens under a single impact load.

关键词： Soft and hard composite rock mass Dynamic properties Split Hopkinson pressure bar(SHPB) Numerical simulation Intrinsic damage model

Chemical composition,energy and amino acid digestibility in double-low rapeseed meal fed to growing pigs

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Journal of Animal Science and Biotechnology 2015年第4期6卷 445-454页

作者： peili Li Fengli Wang Fei wu Jinrong Wang Ling Liu Changhua Lai State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University College of Bio-engineering Henan University of Technology

Background： The nutritional value of rapeseed meal may be variable due to the variation of its chemical composition. And a precise understandin9 of the nutritional value of an ingredient is beneficial for the accurate diet formulation and reduction of feed costs. This study was conducted to determine the chemical composition, dicjestible energy （DE） and metabolizable enercjy （ME） content, and apparent ileal digestibility （AID） and standardized ileal dicjestibility （SID） of amino acids （AA） for growincj pigs. Thirteen solvent-extracted double-low rapeseed meal （DLIRSM） samples were obtained from the main double-low rapeseed producing areas in China. Methods： The DE and ME contents of the 13 DLRSM samples were measured in cjrowin9 pigs （six pigs per DLRSM sample, average initial body weicjht （BW） =48.3 kg）. The AID and SID of AA of 10 DLRSM samples were determined in 12 crossbred barrows （average initial BW = 35.3 kcj） by using two 6 x 6 Latin square designs. Each Latin square comprised one N-flee diet and 5 DLRSM test diets. Results： The chemical composition of DLRSM varied among samples, and the coefficient of variation was greater than ]0 % for ether extract （EE）, neutral detergent fiber （NDF）, acid detergent fiber （ADF）, calcium （Ca）, and total 91ucosinolates. The AA content of DLRSM varied among samples especially for lysine （Lys） and methionine （Met）. On a dry matter （DM） basis, the apparent total tract digestibility （ATFD） of gross energy （GE）, the DE and ME and the ME：DE ratio of DLRSM averaged 62.39 %, 2862 kcal/k9 and 2723 kcal/kcj, and 94.95 %, respectively. The mean value of S1D of Lys was 70.52 % which varied from 66.54-76.54 %. The SID of crude protein （CP）, Met, and threonine （Thr） averaged 72.81%, 82.41%, and 69.76 %, respectively. Conclusions： There was great variability in chemical composition especially in the concentration of EE, NDF and ADF, but no significant differences in energy content of the DLIRSM samples were observed. In addition, the AID and SID of all AA were relatively similar amoncj

关键词： Digestible energy Double-low rapeseed meal Growing pigs Ileal digestibility of amino acids,Metabolizable energy

Effects of Grazing Exclusion on Plant Productivity and Soil Carbon, Nitrogen Storage in Alpine Meadows in Northern Tibet, China

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Chinese Geographical Science 2014年第4期24卷 488-498页

作者： XIONG Dingpeng SHI peili SUN Yinliang wu Jianshuang ZHANG Xianzhou Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

Grazing exclusion is widely adopted in restoring degraded alpine grasslands on the Qinghai-Tibetan Plateau. However, its effectiveness remains poorly understood. In this study, we investigated the effects of grazing exclusion on plant productivity, species diversity and soil organic carbon(SOC) and soil total nitrogen(STN) storage along a transect spanning from east to west of alpine meadows in northern Tibet, China. After six years of grazing exclusion, plant cover, aboveground biomass(AGB), belowground biomass(BGB), SOC and STN were increased, but species diversity indices declined. The enhancement of AGB and SOC caused by grazing exclusion was correlated positively with mean annual precipitation(MAP). Grazing exclusion led to remarkable biomass increase of sedge species, especially Kobresia pygmaea, whereas decrease of biomass in forbs and no obvious change in grass, leguminous and noxious species. Root biomass was concentrated in the near surface layer(10 cm) after grazing exclusion. The effects of grazing exclusion on SOC storage were confined to shallow soil layer in sites with lower MAP. It is indicated that grazing exclusion is an effective measure to increase forage production and enhance soil carbon sequestration in the studied region. The effect is more efficient in sites with higher precipitation. However, the results revealed a tradeoff between vegetation restoration and ecological biodiversity. Therefore, carbon pools recover more quickly than plant biodiversity in the alpine meadows. We suggest that grazing exclusion should be combined with other measures to reconcile grassland restoration and biodiversity conservation.

关键词：植物生产力中国北方土壤碳封育高寒草甸物种多样性指数土壤有机碳储量地上生物量

A Hybrid Compression Framework for Large Scale Trajectory Data in Road Networks

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Chinese Journal of Electronics 2015年第4期24卷 730-739页

作者： wu peili TAN Yu'an ZHENG Jun ZHANG Quanxin LI Yuanzhang CHENG Zijing School of Computer Science and Technology Beijing Institute of Technology Space Star Technology CO. Ltd China Academy of Space Technology

A Hybrid compression framework of trajectory data(HCFT) is proposed for effective compression of tra jectory data with road network limited. It’s different from the present researches which mainly focus on compression of single tra jectory, and further takes data redundancy raised by the similarity of movement pattern of moving objects into consideration. HCFT divides the redundancy of tra jectory data into Single tra jectory redundancy(STR) and Multiple tra jectories redundancy(MTR) and compresses them in a hybrid way(i.e. synchronous compression for STR at first and then asynchronous compression for MTR). We propose an asynchronous extraction algorithm for MTR based on frequent Road track subsequence(RTS), which replaces similar movement route by RTS, with the complexity of calculation significantly reduced. HCFT can not only gain higher compression ratio,but also ensure effectiveness of compressed tra jectory. We also verify effectiveness and superiority of the new method according to the experiments of real tra jectory dataset.

关键词： Trajectory data Movement similarity Road track Dictionary coding Multi-tra jectories compression