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Predictable and Unpredictable Modes of Northern Hemisphere Atmospheric Circulation in CMIP6:Evaluation and Projections
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作者 Kairan YING Dabang JIANG Linhao ZHONG 《Advances in Atmospheric Sciences》 2026年第1期135-156,共22页
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g... Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations. 展开更多
关键词 interannual mode of atmospheric circulation CMIP6 predictable unpredictable EVALUATION projectION
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Global burden of cervical cancer:current estimates,temporal trend and future projections based on the GLOBOCAN 2022 被引量:4
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作者 Jie Wu Qianyun Jin +10 位作者 Yunmeng Zhang Yuting Ji Jingjing Li Xiaomin Liu Hongyuan Duan Zhuowei Feng Ya Liu Yacong Zhang Zhangyan Lyu Lei Yang Yubei Huang 《Journal of the National Cancer Center》 2025年第3期322-329,共8页
Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical ca... Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical cancer as a major public health problem.Methods All data were extracted from the Global Cancer Observatory(GLOBOCAN)2022.Age-standardized incidence rate(ASIR)and mortality rates(ASMR)of cervical cancer were compared and linked to Human Development Index(HDI)between populations.The estimated annual percentage changes(EAPCs)were used to characterize the temporal trend in ASIR/ASMR,and demographic estimates were projected up to 2050.Results Globally,an estimated 662,044 cases(ASIR:14.12/100,000)and 348,709 deaths(ASMR:7.08/100,000)from cervical cancer occurred in 2022,corresponding to the fourth cause of cancer morbidity and mortality in women worldwide.Specifically,42%of cases and 39%of deaths occurred in China(23%and 16%)and India(19%and 23%).Both ASIR and ASMR of cervical cancer decreased with HDI,and similar decreasing links were observed for both early-onset(0–39 years)and late-onset(≥40 years)cervical cancer.Both ASIR and ASMR of overall cervical cancer showed decreasing trends during 2003–2012(EAPC:0.04%and-1.03%);however,upward trends were observed for early-onset cervical cancer(EAPC:1.16%and 0.57%).If national rates in 2022 remain stable,the estimated cases and deaths from cervical cancer are projected to increase by 56.8%and 80.7%up to 2050.Moreover,the projected increase of early-onset cervical cancer is mainly observed in transitioning countries,while decreased burden is expected in transitioned countries.Conclusions Cervical cancer remains a common cause of cancer death in many countries,especially in transitioning countries.Unless scaling-up preventive interventions,human papillomavirus(HPV)vaccination and cervical cancer screening,as well as systematic cooperation within government,civil societies,and private enterprises,the global burden of cervical cancer would be expected to increase in the future. 展开更多
关键词 Cervical cancer INCIDENCE MORTALITY Temporal trend Future projection
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Cancer mortality trends in China from 2013-2021 and projections to 2030
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作者 Xin Liang Yifei Yao +2 位作者 Xiang Li Ting Gao Xiaoqiu Dai 《Cancer Biology & Medicine》 2025年第10期1223-1239,I0023-I0036,共31页
Objective:This study aimed to analyze the temporal trends in cancer mortality in China from 2013-2021 and project the future trends through 2030.Methods:This study was based on the China Causes of Death Surveillance D... Objective:This study aimed to analyze the temporal trends in cancer mortality in China from 2013-2021 and project the future trends through 2030.Methods:This study was based on the China Causes of Death Surveillance Dataset,which covers 2.37 billion person-years.Age-standardized mortality rates(ASMRs)were calculated using Segi’s world standard population and the trends were evaluated via Joinpoint regression.Bayesian age-period-cohort models were used for mortality projections.Contributions of demographic changes(population size and age structure)and risk factors to the mortality burden were quantified using the decomposition analysis.Results:The combined ASMRs for all cancers decreased annually by 2.3%,driven by significant declines in esophageal(4.8%),stomach(4.5%),and liver cancers(2.7%).In contrast,the pancreatic and prostate cancer ASMRs increased by 2.0% and 3.4% annually,respectively.Urban areas demonstrated a more rapid decline in the combined ASMRs for all cancers[average annual percent change(AAPC)=-3.0% in urban areas vs.-2.0% in rural areas],highlighting persistent disparities.Population aging contributed 20%-50% to death increases between 2013 and 2021.The combined ASMRs for all cancers,like the findings of temporal trend analyses,will continue to decrease and the regional(urban and rural)difference is projected to simulate that of the temporal trend through 2030.In fact,cancer deaths are projected to reach 2.4 million by 2030.Conclusions:The cancer burden in China is facing the dual challenges of population aging and urban-rural disparities.It is necessary to prioritize rural screening,control risk factors,such as smoking and diet,and integrate more efficacious cancer prevention and control programmes into the policy to reduce mortality in the future. 展开更多
关键词 Cancer mortality TRENDS projections 2030 China
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Evapotranspiration and Its Components Partitioning Based on an Improved Hydrological Model:Historical Attributions and Future Projections
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作者 Hong Du Sidong Zeng +1 位作者 Yongyue Ji Jun Xia 《Journal of Earth Science》 2025年第6期2689-2707,共19页
Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water ... Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water resources management.In this study,an improved hydrological model is developed to estimate evapotranspiration and its components,i.e.,evaporation(E)and transpiration(T)by integrated the advantages of hydrological modeling constrained by water balance and the water-carbon close relationships.Results show that the improved hydrological model could captures ET and its components well in the study region.During the past years,annual ET and E increase obviously about 2.40 and 1.42 mm/a,particularly in spring and summer accounting for 90%.T shows less increasement and mainly increases in spring while it decreases in summer.Precipitation is the dominant factor and contributes 74.1%and 90.0%increases of annual ET and E,while the attribution of T changes is more complex by coupling of the positive effects of precipitation,rising temperature and interactive influences,the negative effects of solar diming and elevated CO_(2).In the future,ET and its components tend to increase under most of the Shared Socioeconomic Pathways(SSP)scenarios except for T decreases under the very high emissions scenario(SSP5-8.5)based on the projections.From seasonal perspective,the changes of ET and the components are mainly in spring and summer accounting for 75%,while more slight changes are found in autumn and winter.This study highlights the effectiveness of estimating ET and its components by improving hydrological models within water-carbon coupling relationships,and more complex mechanisms of transpiration changes than evapotranspiration and evaporation changes under the interactive effects of climate variability and vegetation dynamics.Besides,decision makers should pay attention to the more increases in the undesirable E than desirable T. 展开更多
关键词 EVAPOTRANSPIRATION ET components attribution analysis future projections water resources HYDROGEOLOGY
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An Integrative Collaborative Project Approach to Climate-Change Resilience and Urban/Regional Sustainability for the Mexico-Lerma-Cutzamala Hydrological Region
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作者 Timothy J. Downs Morgan Ruelle +4 位作者 Nigel Brissett Ravi Hanumantha Marisa Mazari-Hiriart Rob Krueger Edward R. Carr 《Open Journal of Civil Engineering》 2022年第1期101-138,共38页
In a rapidly urbanizing world, the social, economic, and ecological complexities of cities require conceptual and operational innovations to enhance climate resilience and sustainability. We describe our Integrative C... In a rapidly urbanizing world, the social, economic, and ecological complexities of cities require conceptual and operational innovations to enhance climate resilience and sustainability. We describe our Integrative Collaborative Project (ICP) approach to co-create climate resilience in the Mexico-Lerma-Cutzamala Hydrological Region (MLCHR). In recent years, it has suffered from frequent natural disasters, and under climate change scenarios, the intensity and frequency of extreme events, including severe floods, droughts, heat waves and landslides are expected to increase. ICPs are framed as socio-technical capacity building enterprises, with networks operating at multiple scales. The approach differs from other integrative efforts, which tend to be top-down with scant civil society co-ownership, and focus on limited aspects like indicators/assessment, or institutional capacity building. We reimagine all operational stages, from creative thinking, through ethos and concept, assessment, planning, project design, implementation and management, and monitoring and evaluation. The design of ICPs is informed by six integrative domains: 1) project ethos, concept, and framing;2) sectors, topics, and issues;3) spatial and temporal scales;4) stakeholder interests, relationships and capacities;5) knowledge types, models and methods;and 6) socio-technical capacities and networks. Empirically, the approach is based on participatory development practices, pilot project work tackling sustainable water and sanitation in Mexico, and a synthesis of rich experiential knowledge spanning 20 years. The theoretical basis considers a pragmatic knowledge frame, socio-technical transitions literature, and education for social transformation. We describe forward-looking operational details of the Pilot ICP for the Mexico-Lerma-Cutzamala Hydrological Region, with our three-university partnership as catalyst, and a new breed of socio-technical enterprise organization as a key partner, engaging stakeholders at municipal and regional scales. 展开更多
关键词 climate-change Resilience Sustainable Development URBAN REGIONAL Mexico City
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The Observed and Projected Changes of Global Monsoons:Current Status and Future Perspectives
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作者 Tianjun ZHOU Xiaolong CHEN +11 位作者 Wenxia ZHANG Bo WU Ziming CHEN Jie JIANG Xin HUANG Shuai HU Meng ZUO Wenmin MAN Lixia ZHANG Zhun GUO Pengfei LIN Lu WANG 《Advances in Atmospheric Sciences》 2026年第1期30-58,共29页
The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risk... The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risks,including floods and droughts.Recent research associated with the implementation of the Global Monsoons Model Intercomparison Project under the umbrella of CMIP6 has advanced our understanding of its historical variability and driving mechanisms.Observational data reveal a 20th-century shift:increased rainfall pre-1950s,followed by aridification and partial recovery post-1980s,driven by both internal variability(e.g.,Atlantic Multidecadal Oscillation)and external forcings(greenhouse gases,aerosols),while ENSO drives interannual variability through ocean-atmosphere interactions.Future projections under greenhouse forcing suggest long-term monsoon intensification,though regional disparities and model uncertainties persist.Models indicate robust trends but struggle to quantify extremes,where thermodynamic effects(warming-induced moisture rise)uniformly boost heavy rainfall,while dynamical shifts(circulation changes)create spatial heterogeneity.Volcanic eruptions and proposed solar radiation modification(SRM)further complicate predictions:tropical eruptions suppress monsoons,whereas high-latitude events alter cross-equatorial flows,highlighting unresolved feedbacks.The emergent constraint approach is booming in terms of correcting future projections and reducing uncertainty with respect to the global monsoons.Critical challenges remain.Model biases and sparse 20th-century observational data hinder accurate attribution.The interplay between natural variability and anthropogenic forcings,along with nonlinear extreme precipitation risks under warming,demands deeper mechanistic insights.Additionally,SRM’s regional impacts and hemispheric monsoon interactions require systematic evaluation.Addressing these gaps necessitates enhanced observational networks,refined climate models,and interdisciplinary efforts to disentangle multiscale drivers,ultimately improving resilience strategies for monsoon-dependent regions. 展开更多
关键词 global monsoons interannual variability decadal variability detection and attribution climate extreme events projection uncertainty
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A Nexus for East Africa--China-supported projects help East Africans to boost energy, water and food security
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作者 RICHARD WETAYA 《ChinAfrica》 2026年第1期44-45,共2页
Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,B... Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,Bukyiende Subcounty in Uganda where he has been cultivating plantain,coffee and Irish potatoes for the past 16 years. 展开更多
关键词 water security solar technology NEXUS irish potatoes East Africa energy security China supported projects agrivoltaics technologya
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The functional roles of feedback projections in the visual system
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作者 寿天德 《Neuroscience Bulletin》 SCIE CAS CSCD 2010年第5期401-410,共10页
Neurons in the nervous system make connections with ascending feedforward projections and descending feedback projections,as well as projections from neural structures at the identical hierarchical level.These neurons... Neurons in the nervous system make connections with ascending feedforward projections and descending feedback projections,as well as projections from neural structures at the identical hierarchical level.These neurons form extremely complicated neural networks and pathways.Compared with the role of the feedforward projection,much less is known concerning the functional roles of the feedback projection.Visual cortex is a good model for studying functional roles of cortical feedback projections which involve many high functions,such as attention,searching and cognition.The present review mainly focused on the functional roles of feedback projections in the visual system. 展开更多
关键词 feedback projection feedforward projection visual system visual attention oblique effect
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The Antidepressant Effect of Light Therapy from Retinal Projections 被引量:8
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作者 Xiaotao Li Xiang Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第2期359-368,共10页
Observations from clinical trials have frequently demonstrated that light therapy can be an effective therapy for seasonal and non-seasonal major depression. Despite the fact that light therapy is known to have severa... Observations from clinical trials have frequently demonstrated that light therapy can be an effective therapy for seasonal and non-seasonal major depression. Despite the fact that light therapy is known to have several advantages over antidepressant drugs like a low cost,minimal side-effects, and fast onset of therapeutic effect,the mechanism underlying light therapy remains unclear.So far, it is known that light therapy modulates mood states and cognitive functions, involving circadian and noncircadian pathways from retinas into brain. In this review,we discuss the therapeutic effect of light on major depression and its relationship to direct retinal projections in the brain. We finally emphasize the function of the retino-raphe projection in modulating serotonin activity,which probably underlies the antidepressant effect of light therapy for depression. 展开更多
关键词 Light therapy DEPRESSION Retinal projection SEROTONIN OPSIN
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Asian Summer Monsoon Onset in Simulations and CMIP5 Projections Using Four Chinese Climate Models 被引量:10
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作者 ZOU Liwei ZHOU Tianjun 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第6期794-806,共13页
The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropo... The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways (RCP) scenario in which anthropogenic emissions continue to rise throughout the 21 st century (i.e. RCP8.5) by all realizations from four Chinese models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Delayed onset of the monsoon over the Arabian Sea was evident in all simulations for present-day climate, which was associated with a too weak simulation of the low-level Somali jet in May. A consistent advanced onset of the monsoon was found only over the Arabian Sea in the projections, where the advanced onset of the monsoon was accompanied by an increase of rainfall and an anomalous anticyclone over the northern Indian Ocean. In all the models except FGOALS-g2, the enhanced low-level Somali jet transported more water vapor to the Arabian Sea, whereas in FGOALS-g2 the enhanced rainfall was determined more by the increased wind convergence. Furthermore, and again in all models except FGOALS-g2, the equatorial SST warming, with maximum increase over the eastern Pacific, enhanced convection in the central West Pacific and reduced convection over the eastern Indian Ocean and Maritime Continent region, which drove the anomalous anticyclonic circulation over the western Indian Ocean. In contrast, in FGOALS-g2, there was minimal (near-zero) warming of projected SST in the central equatorial Pacific, with decreased convection in the central West Pacific and enhanced convection over the Maritime Continent. The broader-scale differences among the models across the Pacific were related to both the differences in the projected SST pattern and in the present-day simulations. 展开更多
关键词 Asian summer monsoon ONSET climate projection Chinese climate models
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Surface Detection of Continuous Casting Slabs Based on Curvelet Transform and Kernel Locality Preserving Projections 被引量:19
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作者 AI Yong-hao XU Ke 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第5期80-86,共7页
Longitudinal cracks are common defects of continuous casting slabs and may lead to serious quality accidents. Image capturing and recognition of hot slabs is an effective way for on-line detection of cracks, and recog... Longitudinal cracks are common defects of continuous casting slabs and may lead to serious quality accidents. Image capturing and recognition of hot slabs is an effective way for on-line detection of cracks, and recognition of cracks is essential because the surface of hot slabs is very complicated. In order to detect the surface longitudinal cracks of the slabs, a new feature extraction method based on Curvelet transform and kernel locality preserving projections (KLPP) is proposed. First, sample images are decomposed into three levels by Curvelet transform. Second, Fourier transform is applied to all sub-band images and the Fourier amplitude spectrum of each sub-band is computed to get features with translational invariance. Third, five kinds of statistical features of the Fourier amplitude spectrum are computed and combined in different forms. Then, KLPP is employed for dimensionality reduction of the obtained 62 types of high-dimensional combined features. Finally, a support vector machine (SVM) is used for sample set classification. Experiments with samples from a real production line of continuous casting slabs show that the algorithm is effective to detect longitudinal cracks, and the classification rate is 91.89%. 展开更多
关键词 surface detection continuous casting slab Curvelet transform feature extraction kernel locality preserving projections
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Asymmetry of Surface Climate Change under RCP2.6 Projections from the CMIP5 Models 被引量:3
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作者 辛晓歌 程彦杰 +2 位作者 汪方 吴统文 张洁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期796-805,共10页
The multi-model ensemble (MME) of 20 models from the Coupled Model Intercomparison Project Phase Five (CMIP5) was used to analyze surface climate change in the 21st century under the representative con- centration... The multi-model ensemble (MME) of 20 models from the Coupled Model Intercomparison Project Phase Five (CMIP5) was used to analyze surface climate change in the 21st century under the representative con- centration pathway RCP2.6, to reflect emission mitigation efforts. The maximum increase of surface air temperature (SAT) is 1.86℃ relative to the pre-industrial level, achieving the target to limit the global warming to 2℃. Associated with the "increase-peak-decline" greenhouse gases (GHGs) concentration path- way of RCP2.6, the global mean SAT of MME shows opposite trends during two time periods: warming during 2006-55 and cooling during 2056-2100. Our results indicate that spatial distribution of the linear trend of SAT during the warming period exhibited asymmetrical features compared to that during the cool- ing period. The warming during 2006-55 is distributed globally, while the cooling during 2056-2100 mainly occurred in the NH, the South Indian Ocean, and the tropical South Atlantic Ocean. Different dominant roles of heat flux in the two time periods partly explain the asymmetry. During the warming period, the latent heat flux and shortwave radiation both play major roles in heating the surface air. During the cooling period, the increase of net longwave radiation partly explains the cooling in the tropics and subtropics, which is associated with the decrease of total cloud amount. The decrease of the shortwave radiation accounts for the prominent cooling in the high latitudes of the NH. The surface sensible heat flux, latent heat flux, and shortwave radiation collectively contribute to the especial warming phenomenon in the high-latitude of the SH during the cooling period. 展开更多
关键词 climate models climate change projectION CMIP5 RCP2.6
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Text extraction method for historical Tibetan document images based on block projections 被引量:3
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作者 段立娟 张西群 +1 位作者 马龙龙 吴健 《Optoelectronics Letters》 EI 2017年第6期457-461,共5页
Text extraction is an important initial step in digitizing the historical documents. In this paper, we present a text extraction method for historical Tibetan document images based on block projections. The task of te... Text extraction is an important initial step in digitizing the historical documents. In this paper, we present a text extraction method for historical Tibetan document images based on block projections. The task of text extraction is considered as text area detection and location problem. The images are divided equally into blocks and the blocks are filtered by the information of the categories of connected components and corner point density. By analyzing the filtered blocks' projections, the approximate text areas can be located, and the text regions are extracted. Experiments on the dataset of historical Tibetan documents demonstrate the effectiveness of the proposed method. 展开更多
关键词 HISTORICAL TIBETAN document filtered BLOCKS bounding CORNER APPROXIMATE projection COORDINATE
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HF radar sea clutter rejection by nonlinear projections 被引量:3
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作者 Zhou Gongjian Jin Yonggao +1 位作者 Dong Huachun Quan Taifan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期733-737,共5页
In the background of signal detection for high frequency (I/F) radar, the sea clutter is quite significant and can mask some weak target signals. A new clutter rejection method named “nonlinear projection” is give... In the background of signal detection for high frequency (I/F) radar, the sea clutter is quite significant and can mask some weak target signals. A new clutter rejection method named “nonlinear projection” is given to improve the SNR of the target. This approach is based on the recent observation that HF sea clutter may be modeled as a nonlinear deterministic dynamical system. After approximating the multidimensional reconstruction of the clutter by a low-dimensional attractor, projections onto this attractor can separate the clutter from other components. Real sea clutter, simulated target data and real target data are used to show that a nonlinear clutter rejection method is a promising technique to suppress sea clutter and enhances target detection. 展开更多
关键词 HF radar target detection clutter rejection nonlinear projection.
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Projections of Wind Changes for 21st Century in China by Three Regional Climate Models 被引量:13
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作者 JIANG Ying Luo Yong +3 位作者 ZHAO Zongci SHI Ying XU Yinlong ZHU Jinhong 《Chinese Geographical Science》 SCIE CSCD 2010年第3期226-235,共10页
This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studi... This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored. 展开更多
关键词 wind speed projectION regional climate model global climate model
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从《Project 2025》看特朗普第二任期遏制“一带一路”倡议动向
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作者 毛新雅 《海外投资与出口信贷》 2025年第3期13-15,共3页
《Project 2025》由美国保守派公共政策智库传统基金会(Heritage Foundation)编写,着重为应对美国最深层次的挑战提出政策建议。《Project 2025》对中国“一带一路”倡议持竞争和对抗态度,其提出采取强化美国在拉美地区影响力、继续实... 《Project 2025》由美国保守派公共政策智库传统基金会(Heritage Foundation)编写,着重为应对美国最深层次的挑战提出政策建议。《Project 2025》对中国“一带一路”倡议持竞争和对抗态度,其提出采取强化美国在拉美地区影响力、继续实施“印太战略”、变革能源产业政策和针对性恢复国际发展援助等方式,遏制中国“一带一路”倡议,可能对特朗普第二任期相关政策产生影响。 展开更多
关键词 中美关系 “一带一路” 传统基金会 project 2025》
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Full-viewpoint 3D Space Object Recognition Based on Kernel Locality Preserving Projections 被引量:2
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作者 孟钢 姜志国 +2 位作者 刘正一 张浩鹏 赵丹培 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第5期563-572,共10页
Space object recognition plays an important role in spatial exploitation and surveillance, followed by two main problems: lacking of data and drastic changes in viewpoints. In this article, firstly, we build a three-... Space object recognition plays an important role in spatial exploitation and surveillance, followed by two main problems: lacking of data and drastic changes in viewpoints. In this article, firstly, we build a three-dimensional (3D) satellites dataset named BUAA Satellite Image Dataset (BUAA-SID 1.0) to supply data for 3D space object research. Then, based on the dataset, we propose to recognize full-viewpoint 3D space objects based on kernel locality preserving projections (KLPP). To obtain more accurate and separable description of the objects, firstly, we build feature vectors employing moment invariants, Fourier descriptors, region covariance and histogram of oriented gradients. Then, we map the features into kernel space followed by dimensionality reduction using KLPP to obtain the submanifold of the features. At last, k-nearest neighbor (kNN) is used to accomplish the classification. Experimental results show that the proposed approach is more appropriate for space object recognition mainly considering changes of viewpoints. Encouraging recognition rate could be obtained based on images in BUAA-SID 1.0, and the highest recognition result could achieve 95.87%. 展开更多
关键词 SATELLITES object recognition THREE-DIMENSIONAL image dataset full-viewpoint kernel locality preserving projections
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Thailand's economic growth and structural development projections in the context of environmental control 被引量:1
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作者 Sompote Kunnoot 《Chinese Journal of Population,Resources and Environment》 2015年第3期272-280,共9页
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) stand... Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth. 展开更多
关键词 STRUCTURAL development ENVIRONMENTAL control ECONOMIC growth projectION
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Discontinuous element pressure gradient stabilizations for compressible Navier-Stokes equations based on local projections 被引量:2
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作者 骆艳 冯民富 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第2期171-183,共13页
A pressure gradient discontinuous finite element formulation for the compressible Navier-Stokes equations is derived based on local projections. The resulting finite element formulation is stable and uniquely solvable... A pressure gradient discontinuous finite element formulation for the compressible Navier-Stokes equations is derived based on local projections. The resulting finite element formulation is stable and uniquely solvable without requiring a B-B stability condition. An error estimate is Obtained. 展开更多
关键词 discontinuous finite element methods pressure gradient projection methods compressible Navier-Stokes equations error estimation
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BERGMAN TYPE PROJECTIONS ON L^p SPACES 被引量:1
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作者 Kehe Zhu 《Analysis in Theory and Applications》 2005年第2期157-165,共9页
The paper is a survey on the action of Bergman type projections on various Lp on three types of holomorphic function spaces: weighted Bergman spaces, the Bloch spaces. The focus is space, and diagonal Besov spaces.
关键词 Bergman projection Bergman kernel integral operator
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