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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 Jun DU Jiandong GONG Hua TONG Liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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基于Ka/Ku双波段回波强度差约束和多普勒功率谱的微物理和动力参数反演方法和应用 被引量:1
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作者 刘黎平 《大气科学》 CSCD 北大核心 2023年第6期1827-1842,共16页
回波强度定标误差、天线水膜衰减和雨区衰减造成的回波强度偏差对云雷达反演微物理和动力参数有非常重要的影响,准确分析这些偏差对提高反演精度至关重要。为了消除云雷达因定标和天线罩等引起的回波强度和功率谱大小的影响,实现高精度... 回波强度定标误差、天线水膜衰减和雨区衰减造成的回波强度偏差对云雷达反演微物理和动力参数有非常重要的影响,准确分析这些偏差对提高反演精度至关重要。为了消除云雷达因定标和天线罩等引起的回波强度和功率谱大小的影响,实现高精度和雷达全观测范围的反演,本文提出了基于Ka/Ku双波段云雷达回波强度差约束和回波强度谱密度数据的降水内空气垂直运动速度和雨滴谱反演方法(DWR-SZ),并将该方法应用到2020年6月8日和2021年6月1日华南两次对流性云降水垂直结构观测数据,利用雨滴谱仪数据分析了该方法反演结果的改进程度,分析了上升速度对反演的回波强度和微物理参数的影响。该方法首先融合双波段云雷达反演(DWSZ)和单波段小粒子跟踪方法(ST)方法反演的云内空气垂直速度V_(air),形成全观测域的V_(air),然后利用DWSZ方法得到微物理参数初估值,并计算衰减影响,最后利用双波段回波强度差(DWR)调整回波强度系统偏差和反演的微物理参数,使DWR-SZ方法正演得到的DWR与雷达观测值差到达极小。结果表明:(1)采用脉冲压缩技术的高雷达灵敏度模式与采用短脉冲的低灵敏度模式相比,DWSZ方法反演的V_(air)与雷达灵敏度相关性非常小,结果稳定,但这种方法只能应用于含有大粒子的液体降水区(粒子直径大于1.8mm);小粒子跟踪ST方法通常低估V_(air),但在低层的35 dBZ以下降水V_(air)低估程度不大,且灵敏度提高会极大改进Ka波段雷达反演能力;两种方法融合的V_(air)比较合理;(2)雨区衰减和距离是造成ST方法低估V_(air)的主要原因;而固态降水的功率谱非常窄而且陡,灵敏度对固态降水区V_(air)影响不大;(3)采用DWR作为约束,有效减小了回波强度的系统偏差和天线水膜影响,提高了微物理参数的反演准确率;(4)ST方法反演的V_(air)高估了粒子数密度,液体含水量(LWC)和衰减系数,低估了粒子大小,但对天线水膜引起的回波强度系统偏差影响不大。 展开更多
关键词 Ka/Ku 波段双波段云雷达 云微物理动力参数反演 回波强度误差和衰减的订正方法
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政治信息认知偏差分析 被引量:5
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作者 陈相光 李辉 《河南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2011年第1期37-40,共4页
在具体的政治信息认知过程中,认知主体受主体性因素、客体性因素、空间性因素、时间性因素、环境性因素和随机性因素等相互作用的影响,如果未能科学、有效区分政治信息当中的事实和价值成分,会引致事实认知偏差、价值认知偏差和综合认... 在具体的政治信息认知过程中,认知主体受主体性因素、客体性因素、空间性因素、时间性因素、环境性因素和随机性因素等相互作用的影响,如果未能科学、有效区分政治信息当中的事实和价值成分,会引致事实认知偏差、价值认知偏差和综合认知偏差。在政治信息认知过程中,针对引发认知偏差的原因,可以采取以下纠偏策略纠正认知偏差。一是在认知主体对政治信息的认知过程中,采取去首因效应、去近因效应、去光环效应、去定势效应、去社会刻板印象等认知方法。二是在认知主体的判断与决策过程中,针对政治信息的归因偏差,采取关注共同反应的信息、寻找隐藏因素等方法;针对政治信息的直觉偏差,采取积累经验、记录事件的发生频率、重视反馈等方法、重视基率问题;针对政治信息的锚定效应,采取多锚法、反锚法等。 展开更多
关键词 政治信息 认知偏差 纠偏方法
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一类函数积性误差模型最优校正估计的存在性 被引量:1
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作者 徐圣兵 《广州大学学报(综合版)》 2001年第11期26-28,共3页
就非线性回归模型y=axb线性化后,对参数a、b的最小二乘估计进行了校正,并在残差平方和期望最小理论上证明了最优校正系数k和最优校正估计量的存在性.
关键词 非线性回归模型 线性化 最小二乘法 有偏估计 最优校正系数 积性误差模型 函数 最优校正估计量 残差平方和
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Improving reservoir volumetric estimations in petroleum resource assessment using discovery process models 被引量:1
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作者 Osadetz Kirk G. 《Petroleum Science》 SCIE CAS CSCD 2009年第2期105-118,共14页
The reservoir volumetric approach represents a widely accepted, but flawed method of petroleum play resource calculation. In this paper, we propose a combination of techniques that can improve the applicability and qu... The reservoir volumetric approach represents a widely accepted, but flawed method of petroleum play resource calculation. In this paper, we propose a combination of techniques that can improve the applicability and quality of the resource estimation. These techniques include: 1) the use of the Multivariate Discovery Process model (MDP) to derive unbiased distribution parameters of reservoir volumetric variables and to reveal correlations among the variables; 2) the use of the Geo-anchored method to estimate simultaneously the number of oil and gas pools in the same play; and 3) the crossvalidation of assessment results from different methods. These techniques are illustrated by using an example of crude oil and natural gas resource assessment of the Sverdrup Basin, Canadian Archipelago. The example shows that when direct volumetric measurements of the untested prospects are not available, the MDP model can help derive unbiased estimates of the distribution parameters by using information from the discovered oil and gas accumulations. It also shows that an estimation of the number of oil and gas accumulations and associated size ranges from a discovery process model can provide an alternative and efficient approach when inadequate geological data hinder the estimation. Cross-examination of assessment results derived using different methods allows one to focus on and analyze the causes for the major differences, thus providing a more reliable assessment outcome. 展开更多
关键词 Multivariate Discovery Process model sampling bias correction cross-validation Geoanchored method
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