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Parsing Objects at a Finer Granularity: A Survey

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Machine Intelligence Research 2024年第3期21卷 431-451页

作者： Yifan Zhao Jia li Yonghong Tian school of Computer Science Peking UniversityBeijing100871China state key {2. of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing100191China

Fine-grained visual parsing, including fine-grained part segmentation and fine-grained object recognition, has attracted considerable critical attention due to its importance in many real-world applications, e.g., agriculture, remote {2., and space technologies. Predominant research efforts tackle these fine-grained sub-tasks following different paradigms, while the inherent relations between these tasks are neglected. Moreover, given most of the research remains fragmented, we conduct an in-depth study of the advanced work from a new perspective of learning the part relationship. In this perspective, we first consolidate recent research and benchmark syntheses with new taxonomies. based on this consolidation, we revisit the universal challenges in fine-grained part segmentation and recognition tasks and propose new solutions by part relationship learning for these important challenges. Furthermore, we conclude several promising lines of research in fine-grained visual parsing for future research.

关键词： Finer granularity visual parsing part segmentation fine-grained object recognition part relationship

使用Pb数据管道对象实现多数据库备份与更新

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计算机工程与应用 2004年第26期40卷 163-165页

作者：赵祥刘素红屈永华王培娟北京师范大学地理学与遥感科学学院遥感与地理信息系统研究中心北京100875 北京师范大学地理学与遥感科学学院遥感科学国家重点实验室北京100875 北京师范大学地理学与遥感科学学院环境遥感与数字城市北京市重点实验室北京100875

论文介绍了Powerbuilder数据管道(DataPipeline)对象的主要特点与作用,结合数据库存储过程的使用,提出后台多数据库备份与更新的策略及关键技术,并给出其实现方法,为多数据库维护与使用提供了一个实例。

关键词： Powerbuilder数据管道多数据库备份与更新

Geological context of the Chang’e-6 landing area and implications for sample analysis

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The Innovation 2024年第5期5卷 64-71,63页

作者： Zongyu Yue Sheng Gou Shujuan Sun Wei Yang Yi Chen Yexin Wang Honglei lin Kaichang Di Yangting lin Xianhua li Fuyuan Wu key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China state key {2. of remote sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China school of Architecture and Civil engineering Chengdu UniversityChengdu 610106China state key {2. of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

Research on returned samples can provide ground truth for the study of the geological evolution history of the ***,previous missions all collected samples from the near side of the Moon,which is significantly different from the far side of the Moon in terms of the thickness of the lunar crust,magma activity,and ***,the samples from the far side of the Moon are of great significance for a comprehensive understanding of the history of the ***’s Chang’e-6(CE-6)probe has successfully landed on the lunar far side and will return samples in the coming *** the precise location of the CE-6 landing site,a detailed analysis of the geological background is conducted in this *** landing site of CE-6 is within the Apollo crater,which is inside the largest impact basin on the Moon,i.e.,the South Pole-Aitken(SPA)*** to the numerical simulation of the formation process of the SPA basin,CE-6 landed at the edge of the SPA impact melting zone,which is presumably composed of impact melt of the lunar *** Apollo crater subsequently excavated deep material again,which constitutes the basement of the CE-6 landing ***,erupted basalt covered these basement rocks,and they also constitute the main source of the CE-6 *** on the dating method of crater size-frequency distribution,we find that the basalt is2.50 *** CE-6 samples also possibly contain basement rocks as excavated and ejected by craters,and they can provide crucial information for our understanding of lunar geological history along with the basalt samples.

关键词： basalt basement constitute

Carbon dioxide(CO_(2.)emissions from the service industry,traffic,and secondary industry as revealed by the remotely sensed nighttime light data

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International Journal of Digital Earth 2021年第11期14卷 1514-1527页

作者： Kaifang Shi Jingwei Shen Yizhen Wu Shirao liu linyi li school of Geographical Sciences Southwest UniversityChongqingPeople’s Republic of China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station Southwest UniversityChongqingPeople’s Republic of China Chongqing engineering Research Center for remote {2. big Data Application School of Geographical SciencesSouthwest UniversityChongqingPeople’s Republic of China school of remote {2. and Information engineering Wuhan UniversityWuhanPeople’s Republic of China

Exploring carbon dioxide(CO2.emissions from human activities is essential for urban energy conservation and resource *** sensed nighttime lights from the Suomi NPP-VIIRS provide spatial consistency in and a low-cost way of revealing CO2.*** many researches have documented the feasibility of the Suomi NPP-VIIRS data for assessing CO2.emissions,few have systematically revealed the ability of nighttime lights for evaluating CO2.emissions from different industries,such as service industry CO2.emissions(SC),traffic CO2.emissions(TC),and secondary industry CO2.emissions(IC).Here,china was selected as the experimental subject,and we comprehensively explored the relationships between the nighttime lights and SC,TC,and IC,and investigated the factors mediating these *** found that without considering other factors,the nighttime lights only revealed up to 51.2.of TC,followed by 41.7%of IC and 2..7%of *** controlling for city characteristic variables,the models showed that there were positive correlations between the Suomi NPP-VIIRS data and SC,IC,and TC,and that nighttime lights have an Inverted-U relationship with *** Suomi NPP-VIIRS data are more suitable for revealing SC,TC,and IC in medium-sized and large-sized cities than in small-sized cities and megacities.

关键词： Nighttime light data Suomi NPP-VIIRS CO2.emissions transmission mechanism china

Spatial and temporal variabilities of rainstorms over china under climate change

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Journal of Geographical Sciences 2021年第4期31卷 479-496页

作者： HUANG Chang ZHANG Shiqiang DONG linyao WANG Zucheng li {2. CUI Luming Shaanxi key laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127China Institute of Earth Surface System and Hazards Northwest UniversityXi'an 710127China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China Changjiang River Scientific Research Institute Wuhan 430010China state Environmental Protection key {2. of Wetland Ecology and Vegetation Restoration Institute for Peat&Mire ResearchNortheast Normal UniversityChangchun 130021China school of remote {2. and Information engineering Wuhan UniversityWuhan 430070China

Rainstorms are one of the extreme rainfall events that cause serious disasters,such as urban flooding and mountain *** studies have used rain gauge observations to analyze rainstorm events,but relevant information is usually missing in gauge-sparse ***-derived precipitation datasets serve as excellent supplements or substitutes for the gauge *** developing a grid-based rainstorm-identification tool,we used the Tropical Rainfall Measurement Mission(TRMM)Multi-satellite Precipitation Analysis(TMPA)time series product to reveal the spatial and temporal variabilities of rainstorms over{2. during 1998–*** patterns of both increasing and decreasing rainstorm occurrences were detected,with no spatially uniform trend being observed across the whole *** was an increase in the area being affected by rainstorms during the 2.-year period,with rainstorm centers shifting along the southwest–northeast *** occurrence was found to be correlated with local total *** comparing rainstorm occurrence with climate variables such as the El Ni?o-Southern Oscillation and Pacific Decadal Oscillation,we also found that climate change was likely to be the primary reason for rainstorm occurrence in *** study complements previous studies that used gauge observations by providing a better understanding of the spatiotemporal dynamics of{2.’s rainstorms.

关键词： climate change extreme precipitation meteorology rainfall satellite precipitation data

基于ROTI和AATR的测地型GNSS接收机监测北半球高纬度区域电离层闪烁准确性分析

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测绘学报 2024年第7期53卷 1251-1264页

作者：赵东升张雪礼崔双雷王潜心李冠青李龙江李宸栋张克非中国矿业大学环境与测绘学院江苏徐州221116 国家空间科学数据中心北京101407 浙江师范大学浙江金华321004

当前,第2.个太阳周期已进入强活跃时期,能引发大量电离层不规则体,进而对使得穿行其中的GNSS信号产生电离层闪烁。这已成为影响GNSS全球稳定导航定位服务的重要干扰源。对全球电离层闪烁进行广泛且全面的监测是消除闪烁对GNSS干扰的重... 详细信息

当前,第2.个太阳周期已进入强活跃时期,能引发大量电离层不规则体,进而对使得穿行其中的GNSS信号产生电离层闪烁。这已成为影响GNSS全球稳定导航定位服务的重要干扰源。对全球电离层闪烁进行广泛且全面的监测是消除闪烁对GNSS干扰的重要前提,然而传统电离层闪烁监测接收机(ISMR)分布有限,无法满足闪烁全球监测需求;测地型接收机分布广泛,但从其低采样数据中提取的闪烁因子缺乏新太阳周期长时序监测数据验证,导致其闪烁监测可靠性存疑。为此,本文基于近3 a新太阳周期测地型接收机数据,以ISMR提供的闪烁因子为参考,从代表性空间天气事件闪烁响应、日闪烁发生率、闪烁持续时间概率分布、闪烁日发生规律及其随极昼、极夜、地磁指数的特征变化等方面,对比研究了两种测地型接收机电离层闪烁因子(即电离层总电子含量变化率指数ROTI和沿弧段电子含量变化率指数AATR)监测北极高纬度区域电离层闪烁的准确性,并给出了ROTI和AATR在高纬度区域判断闪烁发生的经验阈值。结果表明,ROTI和AATR均能较为准确探测到地磁扰动、太阳活动等因素驱动的区域电离层闪烁,并能有效表征电离层闪烁统计学上的日变化规律,但两种闪烁因子不能准确区分闪烁和电离层电子密度梯度变化,导致在电子密度梯度变化剧烈期间存在较高虚警。该研究成果可为准确选择区域电离层闪烁监测因子提供指导。

关键词： GNSS 电离层闪烁相位闪烁因子测地型接收机

A Novel Inversion Approach for the Kernel-Driven bRDF Model for Heterogeneous Pixels

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Journal of Remote Sensing

Journal of remote sensing 2023年第1期3卷 160-177页

作者： Hanliang li Kai Yan Si Gao Xuanlong Ma Yelu Zeng Wenjuan li Gaofei Yin Xihan Mu Guangjian Yan Ranga b.Myneni state key {2. of remote sensing Science Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China school of Land Science and Technology China University of GeosciencesBeijing 100083China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730020China College of Land Science and Technology China Agricultural UniversityBeijing 100083China state key {2. of Efficient Utilization of Arid and Semi-arid Arable Land in Northern china the Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China INRAE Avignon UniversitéUMR EMMAHAvignon F-84000France Faculty of Geosciences and Environmental engineering Southwest Jiaotong UniversityChengdu 610031China Department of Earth and Environment Boston UniversityBostonMA 02215USA

The bidirectional reflectance distribution function(bRDF)of the land surface contains information relating to its physical structure and *** bRDF modeling for heterogeneous pixels is important for global ecosystem monitoring and radiation balance ***,the original kerneldriven models,which many operational bRDF/Albedo algorithms have adopted,do not explicitly consider the heterogeneity within heterogeneous pixels,which may result in large fitting *** this paper,we attempted to improve the fitting ability of the kernel-driven models over heterogeneous pixels by changing the inversion approach and proposed a dynamic weighted least squares(DWLS)inversion *** performance of DWLS and the traditional ordinary least squares(OLS)inversion approach were compared using simulated *** also evaluated its ability to reconstruct multiangle satellite observations and provide accurate bRDF using unmanned aerial vehicle *** results show that the developed DWLS approach improves the accuracy of modeled bRDF of heterogeneous *** DWLS approach applied to satellite observations shows better performance than the OLS method in study regions and exhibits smaller mean fitting residuals both in the red and near-infrared *** DWLS approach also shows higher bRDF modeling accuracy than the OLS approach with unmanned aerial vehicle *** results indicate that the DWLS inversion approach can be a better choice when kernel-driven models are used for heterogeneous pixels.

关键词： bRDF kernel Inversion

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路段级导航属性信息挖掘

测绘学报 2024年第2期53卷 367-378页

作者：张彩丽向隆刚李雅丽高松峰潘传姣河南城建学院测绘与城市空间信息学院河南平顶山467000 武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079 沈阳建筑大学交通与测绘工程学院辽宁沈阳110000

大量的自动或半自动道路提取方法如雨后春笋,但生成的产品通常缺乏导航属性信息,如路段的等级、限速等,制约“大路优先”“限速提醒”等智能导航服务。因此,本文以路段为分析单元,考虑上下游邻接路段强相关性,提出一种改进的路段等级、... 详细信息

大量的自动或半自动道路提取方法如雨后春笋,但生成的产品通常缺乏导航属性信息,如路段的等级、限速等,制约“大路优先”“限速提醒”等智能导航服务。因此,本文以路段为分析单元,考虑上下游邻接路段强相关性,提出一种改进的路段等级、限速属性信息挖掘方法。首先进行轨迹、路网数据预处理,实现轨迹点与归属路段的连接。然后基于对数据和任务的认识进行多模态道路互补特征设计。最后顾及目标路段及其上下游邻接信息,利用随机森林开展面向路段的等级、限速信息分析。与单类特征相比,集成路网与轨迹特征之后提高了路段等级、限速分类准确率。与仅顾及目标路段进行路段等级、限速分类相比,顾及空间邻接信息进行路段等级、限速分类效果更好。

关键词：众源轨迹导航属性挖掘多模特征融合空间邻接信息道路等级识别道路限速识别

Estimation of net primary productivity and its driving factors in the Ili River Valley,china

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Journal of Arid Land 2018年第5期10卷 781-793页

作者： JIAO Wei CHEN Yaning li Weihong ZHU Chenggang li Zhi state key {2. of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences school of remote {2. and Information engineering Wuhan University

Net primary productivity（NPP）, as an important variable and ecological indicator in grassland ecosystems, can reflect environmental change and the carbon budget level. The Ili River Valley is a wetland nestled in the hinterland of the Eurasian continent, which responds sensitively to the global climate change. Understanding carbon budget and their responses to climate change in the ecosystem of Ili River Valley has a significant effect on the adaptability of future climate change and sustainable development. In this study, we calculated the NPP and analyzed its spatio-temporal pattern of the Ili River Valley during the period 2.00–2.14 using the normalized difference vegetation index（NDVI） and an improved Carnegie-Ames-Stanford（CASA） model. Results indicate that validation showed a good performance of CASA over the study region, with an overall coefficient of determination（R2. of 0.65 and root mean square error（RMSE） of 2..86 g C/（m^2.a）. Temporally, annual NPP of the Ili River Valley was 599.19 g C/（m^2.a） and showed a decreasing trend from 2.00 to 2.14, with an annual decrease rate of –3.51 g C/（m^2.a）. However, the spatial variation was not consistent, in which 55.69% of the areas showed a decreasing tendency, 12.60% of the areas remained relatively stable and 31.71% appeared an increasing tendency. In addition, the decreasing trends in NPP were not continuous throughout the 15-year period, which was likely being caused by a shift in climate conditions. Precipitation was found to be the dominant climatic factor that controlled the inter-annual variability in NPP. Furthermore, the correlations between NPP and climate factors differed along the vertical zonal. In the medium-high altitudes of the Ili River Valley, the NPP was positively correlated to precipitation and negatively correlated to temperature and net radiation. In the low-altitude valley and high-altitude mountain areas, the NPP showed a negative correlation with precipitation and a weakly positive corre

关键词： net primary productivity Carnegie-Ames-Stanford model spatio-temporal pattern climatic impacts precipitation normalized difference vegetation index