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Comparative study of nudged elastic band and molecular dynamics methods for diffusion kinetics in solid-state electrolytes
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作者 林啊鸣 石晶 +1 位作者 魏苏淮 孙宜阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期96-100,共5页
Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynam... Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time. 展开更多
关键词 nudged elastic band method molecular dynamics solid electrolyte ion transport density func-tional theory
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Improving wellbeing of community-dwelling people with mild cognitive impairment: the SENIOR (SystEm of Nudge theory based ICT applications for OldeR citizens) project 被引量:2
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作者 Davide Maria Cammisuli Giada Pietrabissa Gianluca Castelnuovo 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第5期963-966,共4页
Population aging with longer life expectancy represents one of the most relevant challenges of the next future,also because of a significant proportion of older adult people may present with dementia.Motivating senior... Population aging with longer life expectancy represents one of the most relevant challenges of the next future,also because of a significant proportion of older adult people may present with dementia.Motivating senior citizens with mild cognitive impairment to maintain their independence and functional abilities,improve health status and quality of life as well as social interactions,constitutes the main target of preventive medicine.According to a nudge theoretical approach,the SENIOR(SystEm of Nudge theory based ICT applications for OldeR citizens)project–developed thanks to the collaboration among Catholic University of the Sacred Heart,Bicocca University and IRCCS Auxiologico Institute in Milan(Italy)–has been designed to adopt an advanced information and communication technology coaching system able to collect and integrate physiological,psychological and behavioral data,with the final aim of interacting with community-dwelling elderly people suffering from mild cognitive impairment and of providing them personalized feedback on lifestyle management.The SENIOR project proposes to use a smart-watch app for alerting family doctors,sharing information with family members in specific cases and monitoring patients at higher risk in hospital Units,in order to ameliorate health of senior citizens with mild cognitive impairment. 展开更多
关键词 community older adult people information and communication technology mild cognitive impairment nudge theory smart watches
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Research on the construction path of the megacity from the perspective of Nudge Theory:Empirical evidence of the“Park City”construction in Chengdu Tianfu New Area
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作者 Xiaoqin Xie Xinglong Gong Shaojie Pan 《Chinese Journal of Population,Resources and Environment》 2023年第3期163-171,共9页
The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governanc... The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governance”.To expand the diverse paths of constructing megacities,the current research references the nudge theory of behavioral science,adopts the extended case method,and takes Chengdu Tianfu New Area as a typical case to summarize the“nudge”path of“Party City”construction.The study found that the government achieves the lock-in effect by the priming mechanism and uses the nudge strategy of improving environment and guiding public opinion,thereby helping the people make free choices.It realizes the framework effect by the salience mechanism and uses the strategies of highlighting key information and optimizing information delivery methods,which directly affects the behavior of the public.It achieves the commitment effect by the comparison mechanism,including the horizontal comparison and vertical comparison strategies,and gradually realizes the policy goals.It realizes the social norm effect by the imitation mechanism and uses the strategies of creating peer pressure and playing celebrity effect,which in turn influence people’s choices.With the help of the“nudging”mechanism,the construction of the park city has realized the interactive cycle of“government output-citizen feedback”and achieved the goal of“making great change through small actions”.As a new behavioral intervention tool,“nudging”provides an alternative explanation for the construction of the park city in Tianfu New Area and opens up new ideas for the construction of megacities.This study concludes that the construction of megacities can achieve the goal of“common return”through different ways and provides practical inspiration for future urban construction. 展开更多
关键词 Behavior nudge MEGACITIES Common return through different ways Making great change through small actions
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Discussion on the Feasibility of nudge in Education
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作者 Hongyang Liu Lucie Kremenkova 《Journal of Educational Theory and Management》 2021年第1期68-73,共6页
This paper first introduces the definition of nudge,the history of nudge and the advantages of nudge.This concept means a relatively subtle policy shift that encourages people to make decisions that are in their broad... This paper first introduces the definition of nudge,the history of nudge and the advantages of nudge.This concept means a relatively subtle policy shift that encourages people to make decisions that are in their broad self-interest.It relies on insights from behavioral science,and when used ethically,it can be very helpful.Subsequently,the research results of the nudge method in public decision-making fields such as health and environmental protection are listed,inferring the feasibility of nudge method in the field of education,especially learners’specific behavior decision.Then according to the classification of the nudge method by the decision-making system,the research on nudge used in the education field is enumerated.It demonstrates that nudge still has a lot of room for expansion in the field of education. 展开更多
关键词 nudge EDUCATION Decision making STUDY
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青藏高原地区考虑融雪的土壤湿度间接Nudging方案对中国气候模拟的影响
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作者 高德华 崔志强 +3 位作者 李课臣 张飞民 杨凯 王澄海 《气候与环境研究》 北大核心 2025年第3期275-294,共20页
青藏高原土壤湿度的模拟受春季融雪过程的影响,具有较大的不确定性,因此会对夏季气候的模拟产生重要的影响。为探讨春季融雪过程引起的土壤湿度偏差对夏季气候的模拟影响,本文在WRF(WeatherResearch andForecastingmodel)模式中的Pleim-... 青藏高原土壤湿度的模拟受春季融雪过程的影响,具有较大的不确定性,因此会对夏季气候的模拟产生重要的影响。为探讨春季融雪过程引起的土壤湿度偏差对夏季气候的模拟影响,本文在WRF(WeatherResearch andForecastingmodel)模式中的Pleim-Xiu间接同化土壤湿度方案中引入了考虑融雪过程的松弛项,开展了跨季节气候模拟,分析了春季融雪过程对青藏高原土壤湿度及地表非绝热加热模拟的影响,探讨了春季融雪引起的土壤湿度异常对夏季中国气候的影响。结果表明,在陆面模式的同化系统中考虑融雪过程使模拟的土壤湿度更接近观测,但存在空间差异;改进的同化方案降低了高原土壤湿度的误差,尤其对高原南部土壤偏湿的模拟偏差改进较为明显。土壤湿度偏差的减小提高了高原地表潜热的模拟效果,但对地表感热的模拟改进较小。同化系统中考虑融雪过程可提高我国北方夏季降水的模拟能力,并降低我国东部气温偏高的模拟误差。 展开更多
关键词 土壤湿度 Nudging方案 气候模拟 数值模拟 融雪
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利用地面格点Nudging改进华南前汛期暖区强降水的数值预报
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作者 郑宇豪 尹金方 +1 位作者 许先煌 李丰 《大气科学》 北大核心 2025年第2期587-602,共16页
数值模式对华南前汛期暖区强降水的再现能力存在显著的不确定性。2020年5月29日在广东省沿海发生了一次暖区强降水事件,所有数值预报几乎都漏报了此次降水。本研究采用地面格点Nudging技术设计了8组试验,探讨了格点Nudging地面观测资料... 数值模式对华南前汛期暖区强降水的再现能力存在显著的不确定性。2020年5月29日在广东省沿海发生了一次暖区强降水事件,所有数值预报几乎都漏报了此次降水。本研究采用地面格点Nudging技术设计了8组试验,探讨了格点Nudging地面观测资料对数值模拟结果的影响。结果表明,Nudging地面全气象要素(控制试验,EXP1)能够较好地再现广东省沿海岸线线状对流的发生发展时空演变及其强降水。Nudging不同地面要素的敏感性试验表明,Nudging地面水汽直接决定了对流的触发,主要是由于Nudging地面水汽在3小时之内迅速将对流层低层相对湿度从80%增加到趋近于饱和(99%),同时显著降低了对流抑制能、抬升凝结高度和自由对流高度;Nudging地面温度增大了位温扰动,增加了热浮力,一定程度上有助于对流的触发和组织,未Nudging地面温度时对流的发生发展明显滞后,且对流系统组织较松散;Nudging地面风场有助于修正近地层西南风风向,使对流演变和降水量更接近观测。最后开展了6组试验探讨了Nudging时长对模拟结果的影响,结果显示Nudging地面全气象要素6小时的模拟效果与控制试验几乎一致,可较好地再现此次暖区强降水过程。尽管水汽在前3小时之内迅速增加,但一定时间(3小时)的水汽维持有助于对流的快速发展。因此,在模式积分前期(6小时),采用格点Nudging地面加密观测资料一定程度上可改善华南暖区强降水的数值预报性能。 展开更多
关键词 地面格点Nudging 华南前汛期 暖区强降水 数值预报
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A hybrid ConvLSTM-Nudging model for predicting surface soil moisture in the Qilian Mountains,China
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作者 FAN Manhong XIAO Qian +1 位作者 YU Qinghe ZHAO Junhao 《Journal of Arid Land》 2025年第11期1623-1648,共26页
Spatiotemporal forecasting of surface soil moisture(SSM)is recognized as a critical scientific issue in precision agricultural irrigation,regional drought monitoring,and early warning systems for extreme precipitation... Spatiotemporal forecasting of surface soil moisture(SSM)is recognized as a critical scientific issue in precision agricultural irrigation,regional drought monitoring,and early warning systems for extreme precipitation.However,long-term forecasting continues to pose formidable challenges because of the complexity observed across both the spatial and temporal scales.In this study,we used a daily SSM dataset at a 0.05°×0.05°spatial resolution over the Qilian Mountains,China and proposed a hybrid Convolutional Long Short-Term Memory(ConvLSTM)-Nudging model,which combined deep neural networks with data assimilation to increase the accuracy of long-term SSM forecasting.We trained and evaluated the SSM predictive performance of four models(Convolutional Neural Network(CNN),Long Short-Term Memory(LSTM),ConvLSTM,and ConvLSTM with Squeeze-and-Excitation(SE)attention mechanism(ConvLSTM-SE))in both short-term and long-term scenarios.The results showed that all the models perform well under short-term predictions,but the accuracy decrease substantially in long-term predictions.Therefore,we integrated Nudging technique during the long-term prediction phase to assimilate observational information and rectify model biases.Comprehensive evaluations demonstrate that Nudging significantly improves all the models,with ConvLSTM-Nudging achieving the best performance under the 200-d forecasting scenario.Relative to those of the best-performing ConvLSTM model for long-term forecasts,when observation noiseδ=0.00 and observation fraction obs=50.0%,the coefficient of determination(R2)of ConvLSTM-Nudging increases by approximately 82.1%,while its mean absolute error(MAE)and root mean squared error(RMSE)decrease by approximately 84.8%and 77.3%,respectively;the average Pearson correlation coefficient(r)improves by approximately 23.6%,and Bias is reduced by 98.1%.These results demonstrated that although pure deep learning models achieve high accuracy in the short-term predictions,they are prone to error accumulation and systematic drift in long-term autoregressive predictions.Integrating data assimilation with deep learning and continuously correcting the state through observation can effectively suppress long-term biases,thereby achieving robust long-term SSM forecasting. 展开更多
关键词 data assimilation surface soil moisture deep neural networks Convolutional Long Short-Term Memory(ConvLSTM) Squeeze-and-Excitation(SE)attention mechanism Nudging long-term prediction
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Learning about good nutrition with the 5-color front-of-package label"Nutri-Score":an experimental study 被引量:1
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作者 Robin C.Hau Klaus W.Lange 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1195-1200,共6页
The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food products.The impact that the Nutri-Score may have on consumer... The Nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food products.The impact that the Nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect sizes.In the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the Nutri-Scores of the available food items.Participants were instructed to compose a healthy diet plan in order that the question of whether the NutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary lives.We found a substantial(Cohen's d=0.86)positive impact on nutritional quality(as measured by the Nutrient Profiling System score of the Food Standards Agency)and a medium-sized(Cohen's d=0.43)reduction of energy content.Energy content reduction was larger for participants who had initially composed plans with higher energy content.The results suggest that the Nutri-Score has the potential to guide consumers to healthier food choices.It remains unclear,however,whether this potential will be reflected in real-life dietary choices. 展开更多
关键词 Nutri-Score Front-of-package label nudge NUTRITION Health
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The Intersection of Privacy by Design and Behavioral Economics: Nudging Users towards Privacy-Friendly Choices
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作者 Vivek Kumar Agarwal 《Journal of Information Security》 2024年第4期557-563,共7页
This paper conducts a comprehensive review of existing research on Privacy by Design (PbD) and behavioral economics, explores the intersection of Privacy by Design (PbD) and behavioral economics, and how designers can... This paper conducts a comprehensive review of existing research on Privacy by Design (PbD) and behavioral economics, explores the intersection of Privacy by Design (PbD) and behavioral economics, and how designers can leverage “nudges” to encourage users towards privacy-friendly choices. We analyze the limitations of rational choice in the context of privacy decision-making and identify key opportunities for integrating behavioral economics into PbD. We propose a user-centered design framework for integrating behavioral economics into PbD, which includes strategies for simplifying complex choices, making privacy visible, providing feedback and control, and testing and iterating. Our analysis highlights the need for a more nuanced understanding of user behavior and decision-making in the context of privacy, and demonstrates the potential of behavioral economics to inform the design of more effective PbD solutions. 展开更多
关键词 Privacy by Design Behavioral Economics nudges User-Centric Design Data Protection Cognitive Biases HEURISTICS
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A Spatially Dependent Nudging Method and Its Application to a Global Tide Assimilation
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作者 Li LIU Xue'en CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第12期2464-2477,共14页
Tides represent a crucial dynamic process in the ocean and play a vital role in both marine and atmospheric studies;thus,accurate simulation of tidal processes is of the utmost importance in tidal circulation models.B... Tides represent a crucial dynamic process in the ocean and play a vital role in both marine and atmospheric studies;thus,accurate simulation of tidal processes is of the utmost importance in tidal circulation models.Based on the sequential data assimilation method and the concept of the Kalman gain matrix,this paper proposes a new nudging method with spatially dependent coefficients for tidal assimilation.The spatial-dependent nudging method not only retains the advantages of the traditional nudging method but also facilitates the direct determination of a more reasonable spatial distribution of nudging coefficients.Utilizing the M_(2)tidal constituent(the main lunar semidiurnal tide)as an illustration,we conducted assimilation experiments of sea-level data to the barotropic circulation and tide model to assess the global harmonic constants of the M_(2)constituent.The results demonstrate that the spatial-dependent nudging method successfully mitigates deviations of tidal phase lag.Following assimilation using the new method,the deviations of the M_(2)tidal amplitude and phase lag can be reduced by 47%and 18%compared to the traditional nudging method,respectively,while the respective values for the non-assimilated case are as much as 9%and 11%.We also applied the S-nudging method to realistic tidal simulations and noted a significantly enhanced effectiveness relative to traditional methods,making it highly valuable for modeling oceanic tidal circulations. 展开更多
关键词 nudging method ASSIMILATION ocean model tidal simulation
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Impact of Assimilating FY-4A Lightning Data with a Latent Heat Nudging Method on Short-Term Forecasts of Severe Convective Events in Eastern China
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作者 Yanqing GAO Xiaofeng WANG Wei GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第12期2478-2494,共17页
In this study,a latent heat nudging lightning data assimilation(LDA)method independent of the flash rate was developed and tested with data from the Lightning Mapping Imager(LMI)onboard the Feng-Yun-4A(FY-4A)satellite... In this study,a latent heat nudging lightning data assimilation(LDA)method independent of the flash rate was developed and tested with data from the Lightning Mapping Imager(LMI)onboard the Feng-Yun-4A(FY-4A)satellite based on the Weather Research and Forecasting(WRF)model.In this LDA method,the positive temperature perturbations at the lightning location are first calculated by the difference between the moist adiabatic temperature of a lifted air parcel and the model temperature.The positive temperature perturbations in the mixed-phase region are then assimilated by a nudging method to adjust the latent heat within the convective system.Meanwhile,the water vapor mixing ratio is adapted to the temperature perturbations accordingly to constrain the relative humidity to remain unchanged.This method considers the physical nature of the convective system,in contrast with other LDA methods that establish an empirical or statistical relationship between the lightning flash rates and model variables.The impact of this LDA method on short-term(≤6 h)forecasts was evaluated using two severe convective events in eastern China:a multi-region heavy rainfall event and a thunderstorm high-wind event.The results showed that LDA could add thermodynamic information associated with the convective system to the WRF model during the nudging period,leading to a more reasonable storm environment.In the forecast fields,the simulations with LDA produced more realistic convective structures,resulting in an improvement in forecasts of precipitation and high winds. 展开更多
关键词 FY-4A LMI lightning data assimilation latent heat nudging numerical weather prediction
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雷达反射率因子在中尺度云分辨模式初始化中的应用Ⅱ:数值模拟试验 被引量:16
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作者 刘红亚 徐海明 +2 位作者 薛纪善 胡志晋 沈桐立 《气象学报》 CAS CSCD 北大核心 2007年第6期906-918,共13页
将反演的云微物理量和垂直速度采用"牛顿连续松弛逼近"(Nudging)技术应用到GRAPES模式中,对一次梅雨锋暴雨过程进行了数值模拟。通过设计不同的试验方案,分别对水汽、液态水和垂直速度对Nudging效果以及预报结果的影响进行了... 将反演的云微物理量和垂直速度采用"牛顿连续松弛逼近"(Nudging)技术应用到GRAPES模式中,对一次梅雨锋暴雨过程进行了数值模拟。通过设计不同的试验方案,分别对水汽、液态水和垂直速度对Nudging效果以及预报结果的影响进行了考察。研究发现,采用Nudging初始化方法,可使背景场与观测反演资料相协调,实现了模式中对流的热启动,模式预报的开始时刻就产生降水,缩短Spin-up时间。水汽对降水至关重要,对降水的强度和持续时间都有重要影响;云水、雨水和垂直速度决定了初始时刻对流的强弱分布并产生降水;水平风场决定了系统的移动方向,对预报降水的落区有重要影响。模式比较成功地模拟了6 h的降水过程,中尺度天气系统的时空特征比较明显,对流中心上升速度最大值约2.0 m/s,云水含量400 hPa以上较大,最大值约1.5 g/kg,雨水含量500 hPa以下较大,最大约3.0 g/kg,底层辐合高层辐散。反演资料对降水的影响随预报时间的增加而减弱,预报1 h之内反演资料有明显影响,3 h之后的预报则主要依赖模式自身。鉴于仅使用一部雷达资料的反射率因子资料,雷达资料没有覆盖整个模式区域,天气系统被截断,反演和同化过程还采用了一些经验参数方法等原因,数值模拟结果与雷达观测之间还存在一定的差异,有待于更深入的研究。 展开更多
关键词 雷达 Nudging 邻近预报 云模式 热启动
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用多普勒雷达资料调整GRAPES模式云参数对短临预报的影响 被引量:13
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作者 张艳霞 陈子通 +3 位作者 蒙伟光 黄燕燕 戴光丰 丁伟钰 《热带气象学报》 CSCD 北大核心 2012年第6期785-796,共12页
利用华南一次强降水过程,通过雷达回波反演的云雨水及模式背景场的水汽和根据雨水修订的水汽场对GRAPES模式初始场通过Nuding技术进行调整,试图改善模式的临近预报。模拟结果对比发现,模式初始场通过Nudging技术只订正云水、雨水及水汽... 利用华南一次强降水过程,通过雷达回波反演的云雨水及模式背景场的水汽和根据雨水修订的水汽场对GRAPES模式初始场通过Nuding技术进行调整,试图改善模式的临近预报。模拟结果对比发现,模式初始场通过Nudging技术只订正云水、雨水及水汽场2种情形,对模式雷达回波的临近预报效果都有一定的改善,其中前者对0~3h的临近预报效果改善明显,而后者对0~6h的预报效果都有所改善,且后者前3h的改善效果优于前者。对比模式初始场通过Nuding技术订正修订前后的水汽场的预报效果发现,修订后的水汽场的临近预报效果优于修订前的,尤其4~6h的差异较明显。分析原因发现,模式初始场中水汽场的修订,尤其是饱和水汽的修订,对模式预报的水汽场有明显影响,从而影响到了环流场,改善了模式的雷达回波和降水的预报。 展开更多
关键词 雷达反射率 云参数 水汽 降水 Nudging 临近预报
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Nudging资料同化对北极海冰密集度预报的改进 被引量:7
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作者 赵杰臣 杨清华 +4 位作者 李明 李群 李春花 田忠翔 张林 《海洋学报》 CAS CSCD 北大核心 2016年第5期70-82,共13页
北极夏季海冰的快速减少使得北极航道提前开通成为可能。为了给北极冰区船运活动提供及时可靠有效的海冰预报保障,急需提高海冰预报水平。本文基于麻省理工大学通用环流模式(MITgcm),使用牛顿松弛逼近(Nudging)资料同化方法将德国... 北极夏季海冰的快速减少使得北极航道提前开通成为可能。为了给北极冰区船运活动提供及时可靠有效的海冰预报保障,急需提高海冰预报水平。本文基于麻省理工大学通用环流模式(MITgcm),使用牛顿松弛逼近(Nudging)资料同化方法将德国不莱梅大学的第二代先进微波辐射成像仪(AMSR2)海冰密集度资料同化到模式中,建立了北极海冰数值预报系统。设计试验对比3种不同Nudging系数计算方案的改进效果,结果表明选择合适参数后,不同方案均能显著改进海冰密集度初始场。通过设计有无Nudging同化的两组预报试验,结合卫星遥感海冰密集度及中国第五次北极科学考察期间"雪龙"船的走航海冰密集度观测数据,定量分析了Nudging同化方案对北极海冰密集度的24~120h预报结果的改进效果。结果表明,Nudging同化对120h内全北极海冰密集度的空间分布和移动单点目标的海冰密集度预报结果均有显著改善;但在海冰变化很小的情况下,Nudging同化试验的24~120h预报结果均劣于惯性预报结果,说明基于Nudging同化的数值预报系统还需进一步提高预报技巧。 展开更多
关键词 北极海冰 密集度预报 Nudging 资料同化
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基于CCSM3气候模式的同化模拟试验 被引量:7
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作者 凌铁军 王彰贵 +1 位作者 王斌 陈幸荣 《海洋学报》 CAS CSCD 北大核心 2009年第6期9-21,共13页
基于美国NCAR及其他科学家合作发展的共同气候系统模式CCSM3,利用nudging方法开展了把15 m到465 m的次表层海温同化到该模式的研究。1980—2000年的同化试验结果表明,经过同化得到的模拟结果与实际较为一致,较好的再现了中低纬太平洋海... 基于美国NCAR及其他科学家合作发展的共同气候系统模式CCSM3,利用nudging方法开展了把15 m到465 m的次表层海温同化到该模式的研究。1980—2000年的同化试验结果表明,经过同化得到的模拟结果与实际较为一致,较好的再现了中低纬太平洋海洋和大气的平均特征和随时间演变的规律,但仍存在如海表温度偏高、降水偏强等问题。尤其是在大洋的东边界,陆地地形比较陡峭的地区,通常出现较大的偏差。 展开更多
关键词 CCSM3模式 nudging 海温同化
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基于CESM气候模式的ENSO后报试验 被引量:6
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作者 李熠 陈幸荣 +2 位作者 谭晶 黄勇勇 蔡怡 《海洋学报》 CAS CSCD 北大核心 2015年第9期39-50,共12页
基于美国国家大气研究中心(NCAR)开发的通用地球系统模式(CESM),本文设计了nudging次表层海温的同化方案,进行了后报实验。对1982-2011年后报结果的分析表明,通过nudging同化,模式对ENSO现象有一定的模拟和预报能力,对赤道太平洋SST、... 基于美国国家大气研究中心(NCAR)开发的通用地球系统模式(CESM),本文设计了nudging次表层海温的同化方案,进行了后报实验。对1982-2011年后报结果的分析表明,通过nudging同化,模式对ENSO现象有一定的模拟和预报能力,对赤道太平洋SST、纬向风、降水等海洋、大气要素等的后报结果与GODAS和NCEP再分析资料较接近,可以较好地重现历次厄尔尼诺和拉尼娜事件中异常东传的过程,超前1、3、6个月时,模式预报的Nio3指数与CPC指数的相关性分别达到0.88、0.81、0.70。但模式同时也表现出一定的春季预报障碍,秋季起报的后报效果最好,春季最差。对1982/1983和1997/1999两个厄尔尼诺事件的分析表明,模式后报的纬向风、热通量、风应力等大气变量的响应较实际滞后,而海洋的变化与实际情况相似,这与我们的同化方案设置有关,即模式只同化了次表层海温,进而强迫大气的响应,从而导致大气的变化较滞后。 展开更多
关键词 CESM模式 nudging同化 ENSO后报
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基于CESM气候模式的同化模拟实验 被引量:7
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作者 李熠 陈幸荣 +2 位作者 谭晶 黄勇勇 蔡怡 《海洋预报》 2015年第3期1-12,共12页
利用nudging方法将GODAS次表层海温资料同化到"通用地球系统模式"(CESM)中,并分析了同化后的海温、降水、海表面气压等海洋、气象要素。结果表明,同化后的模拟结果与GODAS、NCEP、GPCP等资料的结果较为一致,较好的再现了中低... 利用nudging方法将GODAS次表层海温资料同化到"通用地球系统模式"(CESM)中,并分析了同化后的海温、降水、海表面气压等海洋、气象要素。结果表明,同化后的模拟结果与GODAS、NCEP、GPCP等资料的结果较为一致,较好的再现了中低纬海洋和大气的平均特征和随时间演变的规律,NINO3指数的相关系数达到0.90。但模拟结果仍存在一些问题,如大西洋西边界流偏强,赤道辐合带降水偏多等。 展开更多
关键词 CESM模式 nudging同化 次表层海温
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分析Nudging对辽宁地区降尺度的影响 被引量:3
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作者 易雪 李得勤 +3 位作者 赵春雨 沈历都 敖雪 刘鸣彦 《地球科学进展》 CAS CSCD 北大核心 2018年第5期517-531,共15页
利用分析Nudging方法,选取辽宁省2015年7月和10月作为夏季和秋季代表月份,开展不同分辨率嵌套网格上的分析同化试验,研究在不同分辨率的嵌套网格上使用分析Nudging对地面要素降尺度模拟的影响。结果表明,采用分析Nudging后,可以明显减小... 利用分析Nudging方法,选取辽宁省2015年7月和10月作为夏季和秋季代表月份,开展不同分辨率嵌套网格上的分析同化试验,研究在不同分辨率的嵌套网格上使用分析Nudging对地面要素降尺度模拟的影响。结果表明,采用分析Nudging后,可以明显减小WRF模式模拟高空要素与大尺度背景场的差异,使模式在长时间的积分过程中能够与大尺度背景场保持很好的一致性,且在12 km和4 km分辨率上均采用分析Nudging相对于仅在36 km分辨率嵌套上采用分析Nudging效果更好。对于地面要素影响方面,不同分辨率嵌套网格采用分析Nudging相对于控制试验均可以提高地面2 m温度、相对湿度、10 m风速和降水的模拟准确度。总体来看,分析Nudging应用于12 km分辨率上的降尺度效果整体最优,当进一步在4 km分辨率嵌套上使用分析Nudging后,反而使得模式对温度、降水的模拟变差,说明在区域气候降尺度中,考虑大尺度背景场本身的分辨率,不宜在高分辨率嵌套网格上进一步采用分析Nudging。 展开更多
关键词 区域气候场 WRF模式 分析Nudging 降尺度 气候模拟
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非对称台风风场的动力初始化应用研究 被引量:5
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作者 王亮 陆汉城 +1 位作者 潘晓滨 张云 《气象科学》 CSCD 北大核心 2009年第6期720-726,共7页
在对比NCAR-AFWA三维Bogus(虚拟)风场及风压场方案的基础上,虚拟台风模型中的水平风场采用考虑台风移速、移向、摩擦等客观因素的非对称方案,垂直风场采用考虑高空反气旋环流的风廓线方案,然后利用Nudging动力初始化技术形成新的模式初... 在对比NCAR-AFWA三维Bogus(虚拟)风场及风压场方案的基础上,虚拟台风模型中的水平风场采用考虑台风移速、移向、摩擦等客观因素的非对称方案,垂直风场采用考虑高空反气旋环流的风廓线方案,然后利用Nudging动力初始化技术形成新的模式初始场。最后对"云娜"台风进行数值模拟,结果表明:通过合理引入客观因子及观测事实对台风Bogus模型进行构建,并利用同化方法使各个物理量相互协调,可以使初始场与实况更加接近,从而在一定程度上提高台风路径及强度的预报水平,并对降水分布的预报效果也有所改善。 展开更多
关键词 虚拟台风方案 非对称风场 Nudging动力初始化
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TRMM卫星的闪电观测资料在中尺度数值模式中的Nudging同化应用研究 被引量:8
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作者 冉令坤 周玉淑 《大气科学》 CSCD 北大核心 2011年第6期1145-1158,共14页
在以往研究的基础上,本文提出一种利用TRMM卫星闪电观测资料改善中尺度数值模式水物质初始场的Nudging同化技术,这是把物理初始化方法与Nudging同化方法相结合的一种技术。根据TRMM卫星闪电观测水平分布,对水汽和云凝结物进行Nudging同... 在以往研究的基础上,本文提出一种利用TRMM卫星闪电观测资料改善中尺度数值模式水物质初始场的Nudging同化技术,这是把物理初始化方法与Nudging同化方法相结合的一种技术。根据TRMM卫星闪电观测水平分布,对水汽和云凝结物进行Nudging同化,对积云对流参数化方案进行调整,改变模式初始水汽和云凝结物场的含量,以达到提高中尺度数值模式初始场质量的目的。本文把这种Nudging同化技术应用于一次短时降水过程的中尺度数值模拟,结果分析表明,这种Nudging同化技术有利于增加模式初始场中水汽和云凝结物含量,特别是水汽和云水的含量,实现水汽和云凝结物的合理空间分布,改善中尺度数值模式短时降水和云凝结物的预报效果,这在一定程度上验证了该Nudging同化技术的可行性。 展开更多
关键词 Nudging同化 TRMM卫星 闪电观测 云凝结物
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