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秋季北大西洋马蹄型海温异常与初冬我国气温年际变化的联系

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大气科学 2024年第3期48卷 1131-1143页

作者：李忠贤王庭轩曾刚邓伟涛南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心南京210044 南京信息工程大学大气科学学院南京210044

本文基于Hadley中心的海表温度资料、全国160站气温资料以及National Centers for Environmental Prediction/National Center for Atmospheric Research(NCEP/NCAR)的再分析资料,运用经验正交函数(empirical orthogonal function,EOF)分解和相关分析等多种统计方法,研究了1951~2020年秋季(9~11月)北大西洋海温年际异常的主要特征及其对初冬(12月)我国气温异常的影响。结果表明:秋季北大西洋海温异常EOF的第一模态是纽芬兰岛东南部海温为负(正)距平,北大西洋副极地和副热带及其东部海温为正(负)距平的马蹄型海温模态,方差贡献率为20.5%。研究表明,秋季北大西洋马蹄型海温异常与我国大部分地区初冬气温异常有显著的正相关关系,即秋季北大西洋马蹄型海温模态呈正位相时,我国大部分地区初冬气温偏高,反之,我国大部分地区初冬气温偏低。进一步分析表明,秋季北大西洋马蹄型海温异常能够持续到初冬。当秋季北大西洋马蹄型海温呈正(负)位相时,初冬北大西洋副极地和副热带海温异常通过加热(冷却)异常能够引起局地对流层上层的辐散(辐合)运动,并且激发出南、北两支Rossby波列。其中,北支波列由北大西洋副极地向东北方向传播至巴伦支海附近,然后沿西伯利亚向东南方向传播至我国上空;南支波列由北大西洋副热带向东传播至我国上空。在南、北支波列的影响下,我国上空对流层上层出现异常辐合(辐散),与之伴随的异常下沉(上升)运动使得我国上空云量减少(增加),到达地表的短波辐射增加(减少),同时地表向低层大气传输的长波辐射增加(减少),在非绝热加热的作用下,我国大部分地区气温偏高(偏低)。利用NCAR Community Atmosphere Model version 5.3(CAM5.3)模式模拟了北大西洋马蹄型海温异常对初冬大气环流、辐射强迫和气温的影响,模拟结果与观测资料统计分析结果基本一致,进一步表明该海温模态能够激发出遥相关波列,影响东亚大气环流异常,通过非绝热加热的作用影响我国气温异常的年际变化。

关键词：北大西洋海温初冬气温非绝热加热年际变化

基于Retinex里双分量改进的微光图像增强方法

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应用光学 2024年第4期45卷 819-827页

作者：陈华腾刘磊钱芸生邓伟涛石峰南京理工大学电子工程与光电技术学院江苏南京210094 微光夜视重点实验室陕西西安710065

近年来,微光图像增强技术备受关注,但仍存在一些问题。例如,有时暗区域没有完全改善,有时光源或光源附近的明亮区域曝光过度。针对以上问题,提出了一种基于Retinex模型里照度分量和反射分量双增强的图像增强方法。该方法首先将原始图像... 详细信息

近年来,微光图像增强技术备受关注,但仍存在一些问题。例如,有时暗区域没有完全改善,有时光源或光源附近的明亮区域曝光过度。针对以上问题,提出了一种基于Retinex模型里照度分量和反射分量双增强的图像增强方法。该方法首先将原始图像由RGB空间转换到HSV空间,并提取其中的V分量进行后续处理;然后对V分量进行引导滤波获得图像照度分量,根据Retinex理论通过分解得到图像的反射分量;接着对照度分量进行全局自适应亮度增强,对反射分量进行多尺度细节加强;再将增强后的照度分量和反射分量按照Retinex模型重构得到V分量重构图,并经过非线性变换处理和局部对比度增强处理;最终转换回RGB空间获得最终增强图。实验结果表明,该方法的峰值信噪比(peak signal-to-noise ratio,PSNR)和结构相似指数(structural similarity index measure,SSIM)评价值分别为17.741和0.765,具有更好的图像质量,较其他方法表现出更好的增强效果。

关键词：微光图像增强 Retinex模型全局亮度增强局部对比度增强细节增强

The design and engineering strategies of metal tellurides for advanced metal-ion batteries

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Journal of Energy Chemistry 2024年第2期89卷 579-598,I0013页

作者： Wenmiao Zhao Xiaoyuan Shi Bo Liu Hiroshi Ueno Ting deng weitao Zheng Key Laboratory of Automobile Materials of MOE School of Materials Science and EngineeringJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchun 130012JilinChina Key Laboratory of Polyoxometalate Science of Ministry of Education Northeast Normal UniversityChangchun 130024JilinChina Key Laboratory of Preparation and Application of Environmental Friendly Materials(Jilin Normal University) Ministry of EducationChangchun 130103JilinChina Creative Interdisciplinary Research Division The Frontier Research Institute for Interdisciplinary Sciences(FRIS)Department of ChemistryGraduate School of ScienceTohoku UniversitySendai 980-8578Japan

Owning various crystal structures and high theoretical capacity,metal tellurides are emerging as promising electrode materials for high-performance metal-ion batteries(MBs).Since metal telluride-based MBs are quite new,fundamental issues raise regarding the energy storage mechanism and other aspects affecting electrochemical *** volume expansion,low intrinsic conductivity and slow ion diffusion kinetics jeopardize the performance of metal tellurides,so that rational design and engineering are crucial to circumvent these ***,this review provides an in-depth discussion of recent investigations and progresses of metal tellurides,beginning with a critical discussion on the energy storage mechanisms of metal tellurides in various *** the following,recent design and engineering strategies of metal tellurides,including morphology engineering,compositing,defect engineering and heterostructure construction,for high-performance MBs are *** primary focus is to present a comprehensive understanding of the structural evolution based on the mechanism and corresponding effects of dimension control,composition,electron configuration and structural complexity on the electrochemical *** closing,outlooks and prospects for future development of metal tellurides are *** work also highlights the promising directions of design and engineering strategies of metal tellurides with high performance and low cost.

关键词： Metal tellurides Metal-ion battery Energy storage mechanism Material design and engineering

Market Operation of Energy Storage System in Smart Grid:A Review

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Energy Engineering 2024年第6期121卷 1403-1437页

作者： Li deng Jiafei Huan Wei Wang weitao Zhang Liangbin Xie Lun Dong Jingrong Guo Zhongping Li Yuan Huang Yue Xiang North China Dispatching Center North China Branch of State Grid Corporation of ChinaBeijing100053China College of Electrical Engineering Sichuan UniversityChengdu610065China

As a flexible resource,energy storage plays an increasingly significant role in stabilizing and supporting the power system,while providing auxiliary ***,the current high demand for energy storage contrasts with the fuzzy lack of market-oriented mechanisms for energy storage,the principle of market-oriented operation has not been embodied,and there is no unified and systematic analytical framework for the business ***,the dispatch management model of energy storage in actual power system operation is not ***,the specific scheduling process and energy storage strategy on the source-load-network side could be more specific,and there needs to be a greater understanding of the collaborative scheduling process of the multilevel scheduling *** this basis,this paper reviews the energy storage operation model and market-based incentive mechanism,For different functional types and installation locations of energy storage within the power system,the operational models and existing policies for energy storage participation in the market that are adapted to multiple operating states are *** the point of view of the actual scheduling and operation management of energy storage in China,an energy storage regulation and operation management model based on“national,provincial,and local”multilevel coordination is proposed,as well as key technologies in the interactive scenarios of source-load,network and storage.

关键词： Energy storage operation marketization scheduling management national-branch-provincial local dispatch

盗窃犯罪易发地的构成、影响及其区域异质性:基于地理探测器方法

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地理研究 2022年第11期41卷 2884-2896页

作者：张延吉庄宇丹邓伟涛郭华贵福州大学人文社会科学学院福州350116 福州大学建筑与城乡规划学院福州350116 福州市城乡空间规划行业技术创新中心福州350116 蕾奥规划设计咨询股份有限公司深圳518049

本文旨在识别盗窃犯罪易发地的主要类型、影响强度及其区域异质性特征,同时厘清地理探测器在犯罪地理研究中的适用性。利用北京中心城区的多源大数据,研究发现:(1)在全域范围内,37类设施均属显著的盗窃易发地,道路边界、行政边界、用地... 详细信息

本文旨在识别盗窃犯罪易发地的主要类型、影响强度及其区域异质性特征,同时厘清地理探测器在犯罪地理研究中的适用性。利用北京中心城区的多源大数据,研究发现:(1)在全域范围内,37类设施均属显著的盗窃易发地,道路边界、行政边界、用地边界也是盗窃高发的边缘地带,影响力突出的盗窃易发地更具备犯罪模式理论提及的犯罪引致条件。(2)如社会解组理论所言,随着社会解组程度减弱,犯罪易发地的类型数量及其对盗窃分布的影响逐渐下降。除低解组区外,各类设施及边界的相对影响排序基本相同。(3)因未考虑混淆因素干扰,地理探测器容易高估解释变量的作用,与负二项回归结果的吻合度不高。而结合排除控制法,将混淆因素同质化的样本进行分区分析是规避外生变异和稳健运用地理探测器的可行路径。

关键词：犯罪模式理论社会解组理论地理探测器刑事判决书犯罪地理学

Winter-Spring Precipitation Variability in Pakistan

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American Journal of Climate Change 2015年第1期4卷 115-139页

作者： Iftikhar Ahmad Romana Ambreen Zhaobo Sun weitao deng Department of Geography University of Balochistan Quetta Pakistan Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University of Information Science & Technology Nanjing China

This study investigates the spatial-temporal variability of winter-spring (February-March-April) precipitation (WSP) in Pakistan over the period of 1961-2006 by making use of Empirical Orthogonal Function (EOF). The EOF analysis is based on ground observed data, reanalysis NCEP/NCAR of various geopotential heights and NOAA extended reconstructed sea surface temperatures (ERSST.v3). The significant modes are obviously variable at interannual time scale. The leading mode shows the node of maximum spatial variability anchored over the Peshawar Valley and Azad Kashmir (PVAK) axis. The pattern is associated with strong (weak) westerly jet over the Middle East. The pattern is also found closely associated with post monsoon and early winter El Nino. The Nino4 index can be an appropriate predictor for the first consistent single node pattern. The second significant mode represents a tripole pattern with areas of prominent variability over northwestern Pakistan, Quetta-Kalat region and northeastern Punjab. The pattern is found to be pro-NAO and in relation to this pattern, warm and stable SST anomalies appearing in the southern mid-latitudes of Indian and Atlantic basins.

关键词： Pakistan Winter-Spring Precipitation EOF Spatial Variability Interannual Variability

Spatial-Temporal Variations in January Precipitation over the Period of 1950-2000 in Pakistan and Possible Links with Global Teleconnections: Geographical Perspective

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American Journal of Climate Change 2014年第4期3卷 378-387页

作者： Iftikhar Ahmad Romana Ambreen Shahzad Sultan Zhaobo Sun weitao deng Department of Geography University of Balochistan Quetta Pakistan Pakistan Meteorological Department Islamabad & Institute of Space and Earth Information Science Chinese University of Hong Kong Hong Kong China Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University of Information Science & Technology Nanjing China

Empirical Orthogonal Function (EOF) was performed to investigate spatial variation in January precipitation over Pakistan using ground observed mean monthly precipitation data from 1950-2000 with a combination of gridded reanalysis data of sea level pressure (SLP) and 500 hPa geopotential height. The leading EOF mode captures 37.51% of the total variance and the spatial-temporal variability of January precipitation was consistent in the study area. The temporal changes explicate non-periodic interannual variability and some tacit interdecadal variation. The anomalous condition is more prominent along the western bordering mountains and northern high mountainous region than any other region of Pakistan. Based on results the study reveals spatial-temporal variation in January precipitation and possible links with global teleconnections located both in the proximity as well as in the remote areas from the study locus.

关键词： Pakistan January Precipitation EOF Analysis Spatial-Temporal Variability

Spatial-Temporal Variations in January Temperature in Pakistan and Their Possible Links with SLP and 500-hPa Levels over the Period of 1950-2000: A Geographical Approach

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Atmospheric and Climate Sciences 2014年第4期4卷 524-533页

作者： Iftikhar Ahmad Romana Ambreen Shahzad Sultan Zhaobo Sun weitao deng Department of Geography University of Balochistan Quetta Pakistan Key laboratory of Meteorological Disaster Ministry of Education Nanjing University of Information Science & Technology Nanjing China Pakistan Meteorological Department Islamabad Pakistan

By making use of Empirical Orthogonal Function (EOF) analysis the spatial and temporal variability was investigated in January over the period of 1950 to 2000 in Pakistan. The analysis is based on the combination of ground observed mean monthly temperature data and National Centre for Environmental Prediction (NCEP) reanalysis data of sea level pressure (SLP) and 500-hPa fields. The results reasonably reveal that the variation in January temperature have links with global teleconnections at SLP and 500-hPa pressure heights. The analysis shows variability at interannual to interdecadal time scale. The interannual variation is more prominent than the interdecadal signal of temperature anomaly. The simulated coefficient patterns show reasonable variation with regional detail from south (north) to north (south) in the study area. The study could be useful as baseline information for climate change studies in Pakistan.

关键词： Pakistan January Temperature Interannual Variability Spatial Variations Empirical Orthogonal Function

采用主从开关表的矩阵变换器电机系统直接转矩控制策略

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电机与控制学报 2023年第10期27卷 151-159页

作者：邓惟滔奚菲若钟琪刘郁陈俊杰谢文武湖南理工学院信息科学与工程学院湖南岳阳414006

本文提出一种采用主从开关表的矩阵变换器电机系统直接转矩控制策略。该策略仅使用6个旋转矢量来驱动电机,达到消除共模电压的目的。为了克服相邻旋转矢量之间的角度不断变化的困难,将旋转矢量分为逆时针旋转和顺时针旋转两组,同组的相... 详细信息

本文提出一种采用主从开关表的矩阵变换器电机系统直接转矩控制策略。该策略仅使用6个旋转矢量来驱动电机,达到消除共模电压的目的。为了克服相邻旋转矢量之间的角度不断变化的困难,将旋转矢量分为逆时针旋转和顺时针旋转两组,同组的相邻矢量之间具有固定的夹角。将逆时针旋转矢量用于建立主开关表,顺时针旋转矢量用于建立从开关表,根据定子磁链相对于各组中旋转矢量的夹角查找相应开关表。实验结果表明,与使用有效矢量的传统直接转矩控制相比,本文方法可充分实现共模电压的抑制,并且满足控制系统动、静态性能的基本要求。

关键词：矩阵变换器永磁同步电机直接转矩控制共模电压旋转矢量开关表