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Partition of Forecast Error into Positional and Structural Components

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Advances in Atmospheric Sciences 2021年第6期38卷 1012-1019页

作者： Isidora JANKOV Scott GREGORY Sai RAVELA zoltan toth Malaquías PEÑA Global Systems Laboratory NOAA/OARBoulderCO 80305USA General Atomics Electromagnetic Systems GroupLongmontCO 80501USA Earth Signals and Systems Group EarthAtmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMA 02139USA Department of Civil and Environmental Engineering University of Connecticut StorrsCT 06269USA

Weather manifests in spatiotemporally coherent *** forecasts hence are affected by both positional and structural or amplitude *** has been long recognized by practicing forecasters(cf.,e.g.,Tropical Cyclone track and intensity errors).Despite the emergence in recent decades of various objective methods for the diagnosis of positional forecast errors,most routine verification or statistical post-processing methods implicitly assume that forecasts have no positional *** Forecast Error Decomposition(FED)method proposed in this study uses the Field Alignment technique which aligns a gridded forecast with its verifying analysis *** total error is then partitioned into three orthogonal components:(a)large scale positional,(b)large scale structural,and(c)small scale error *** use of FED is demonstrated over a month-long MSLP data *** expected,positional errors are often characterized by dipole patterns related to the displacement of features,while structural errors appear with single extrema,indicative of magnitude *** most important result of this study is that over the test period,more than 50%of the total mean sea level pressure forecast error variance is associated with large scale positional *** importance of positional error in forecasts of other variables and over different time periods remain to be explored.

关键词： forecast error orthogonal decomposition positional structural

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全球中期集合预报系统地表扰动试验

全球中期集合预报系统地表扰动试验

中国气象学会2007年年会

作者：邓国朱跃建 zoltan toth Richard Wobus 国家气象中心 Environmental Modeling Center NCEP/NWS/NOAAMD20746U.S.A Environmental Modeling Center NCEP/NWS/NOAAMD20746U.S.A Environmental Modeling Center NCEP/NWS/NOAAMD20746U.S.A

在NCEP全球集合预报系统框架中加入地表扰动模块,使该系统大气和地表（包括陆面、海洋、冰面）过程均具备初值扰动的能力,而且在地表和大气要素间存在相互作用和反馈。利用新的试验系统,可以方便地进行控制试验和扰动试验:前者仅对大气...

在NCEP全球集合预报系统框架中加入地表扰动模块,使该系统大气和地表（包括陆面、海洋、冰面）过程均具备初值扰动的能力,而且在地表和大气要素间存在相互作用和反馈。利用新的试验系统,可以方便地进行控制试验和扰动试验:前者仅对大气要素进行扰动,所有地表要素保持不变;后者则对大气要素和地表要素进行扰动,而地表扰动的方法有多种可选,如利用模式预报量替换、增长模繁殖法、集合变换方法（ET,该方法程序未来得及测试）。方法以EMC现在运行的全球集合预报系统为基本框架,共有5个集合预报成员,包括一个控制试验和4个扰动成员;大气要素扰动方法为ET和热带气旋重定位技术;地表扰动要素:开始冷启动,在6小时后,利用扰动的地表预报场作为模式地表要素初值,每6小时完成一次循环。扰动的要素包括4层土壤温度,4层土壤湿度;试验时间2006年8月22日到2006年11月22日。试验结果表明,地表扰动的初步结果表明,地表状况与大气之间存在相互作用,地表扰动对于大气要素有明显的反馈,可以改变大气要素和模式预报结果,包括环流形势、降水分布和范围有明显变化,但是这种变化本身短期内对集合预报系统整体的离散度增加并不显著;特别是从土壤温度和湿度不同深度离散度随时间变化表明,3个月内随土壤深度增加,离散度仍保持不断增长的趋势,因此,地表状态与大气要素部分的相互作用是一个慢过程,需要经过长时间的反馈和SPIN-UP,集合预报系统才能达到稳定的状态,地表过程的不确定性对模式的反馈才可能达到显著的状态,才能真正体现大气和地表相互作用。

关键词：

来源： cnki会议评论

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预报“接近正常”,为何常失误

气象科技 1992年第2期20卷 1-9页

作者： HUUG M.VAN DEN DOOL zoltan toth 张瑞雪马里兰大学气象系

许多研究表明当把分级预报的得分分解为单个级别时,N 级(“接近正常”级)的得分即使不为负值或零,往往也低。我们看到许多对接近正常天气预报困难的讨论,但文献中还没有令人满意的解释。在此给出几个新的实例,通过一些统计学分析和得分... 详细信息

许多研究表明当把分级预报的得分分解为单个级别时,N 级(“接近正常”级)的得分即使不为负值或零,往往也低。我们看到许多对接近正常天气预报困难的讨论,但文献中还没有令人满意的解释。在此给出几个新的实例,通过一些统计学分析和得分的定义,试图解释此种现象。这里引进均方根误差(rms)和得分(skill)的定义,专指给定的距平的。3级预报中 N 级得分低,原因是(a)当具有准高斯分布的预报量的分级宽度在中心附近很窄时,我们预报方法的 rms 误差与预报振幅关系不大。(b)检验观测值偏离 N 级的机会(其两侧均有偏离机会)比其它级的机会大(半闭合级只有单侧偏离机会)。从另外一层意义上解释是:由于在得分的定义中,所需检验方法以随机预报为参考,因而在均值附近得分低。从 rms 的意义上来说,随机预报在均值附近效果最好。均值附近预报得分低并不只出现在分级预报或任何特定时间。本文不是给出一个解决方法,而是提醒人们不能过分解释等级评分的概念。似乎均值附近预报得分低,主要是定义所造成,因而不需要物理学和动力学方面的解释。当取持续性预报为参考代替随机预报时,所有问题就都迎刃而解了。最后,我们注意到,远在我们对评分作预报之前,在实际中均值附近得分低已应用了预测预报得分的概念。分析表明只要预报距平相对于预报 rms 误差来说比较小,则可以预测距平相关随预报幅度线性增加。这已被 Tracton 等(1989)从经验上发现。

关键词：天气预报观测误差正常

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57万亿电动车市场引爆

商业周刊（中文版） 2024年第1期 42-47页

作者： Malcolm Scott Amy Stillman zoltan Simon Patpicha Tanakasempipat Paul Burkhardt Jacob Lorinc 许诺(译) 不详

长达一个世纪的内燃机汽车时代在迈向电动车时代,这一历史性转变正在世界经济的某些令人意想不到的角落制造引爆点。而且现在才刚刚开始。在自然资源丰富的加拿大“火环地带”,由于对环境退化的担忧,电动汽车生产所需矿物的开采许可审... 详细信息

长达一个世纪的内燃机汽车时代在迈向电动车时代,这一历史性转变正在世界经济的某些令人意想不到的角落制造引爆点。而且现在才刚刚开始。在自然资源丰富的加拿大“火环地带”,由于对环境退化的担忧,电动汽车生产所需矿物的开采许可审批速度放缓,不同的环保目标之间在发生冲突。

关键词：内燃机汽车环境退化电动汽车自然资源历史性转变引爆点电动车加拿大

Morphological and microcirculatory evaluation of the rat testis after detorsion with or without a capsular release with a tunica vaginalis flap

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Asian Journal of Andrology 2016年第3期18卷 462-466,I0010,I0011页

作者： Tamas Jozsat zoltan Klarik Ferenc Kiss Eniko toth Anita Mester zoltan Hargitai Yi-Che Changchien Magdalena Fossum Norbert Nemeth Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden Department of Pediatric Surgery Division of Urology Astrid Lindgren Children's Hospital. Karolinska University Hospital Stockholm Sweden Department of Operative Techniques and Surgical Research Institute of Surgery Faculty ot MedicineUniversity of Debrecen Hungary Department of Pathology Kenezy Gyula Hospital Uebrecen Hungary

Testicular torsion may lead to serious ischemia, and the viability depends on the duration of torsion and the effect of ischemia-reperfusion. Testicular decompression and tunica vaginalis flap application technique were introduced in 2008 by Kutikov et al. We aimed to examine the impact of this method on the testicular microcirculation and hemorheological parameters in a rat model. Six adult rats underwent bilateral scrotal exploration. Intravaginal torsion of the testis was created by 720° rotation on both sides for 2 h. After detorsion, the right testes underwent tunica albuginea incision and tunica vaginalis flap application. Testicular microcirculation was monitored and hematological parameters, erythrocyte deformability, and aggregation were determined. Measurements were performed before and after torsion, directly after detorsion, on the 1^st-2^nd and 8^th postoperative day. After the last sampling, testicles were removed to determine their volume for histological examinations. The microcirculatory parameters demonstrated slight differences between testicles. Apical zone of the left （nondecompressed） testicles had elevated compared to the middle zone （P 〈 0.05）. On the 2^nd and 8^th day, the microcirculation of the testes normalized but not equally. The erythrocyte aggregation and deformability decreased by the 8^th day. Both testicles underwent atrophy and epithelial necrosis, but the volume of the decompressed ones was lower （1.07±0.08 vs 1.25 ± 0.31）. Histologically, there was no significant difference in epithelial damage score between decompressed and nondecompressed testes. In conclusion, 2-h ischemia led to alteration in testicular microcirculation, reduction in volume, changes in hemorheological parameters and serious epithelial necrosis both in decompressed and nondecompressed testicles without remarkable differences.

关键词： ischemia rat model reperfusion spermatic cord torsion surgical flaps testicular compartment syndrome testis

Diurnal variation of aethalometer correction factors and optical absorption assessment of nucleation events using multi-wavelength photoacoustic spectroscopy

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Journal of Environmental Sciences 2019年第9期31卷 96-109页

作者： Tibor Ajtai Gergely Kiss-Albert Noemi Utry Adam toth Andras Hoffer Gabor Szabo zoltan Bozoki Department of Optics and Quantum Electronics University of Szeged H-6720 Szeged Hungary Hilase Development Production Service and Trading Limited Szekesfehervar H-8000 Hungary MTA-SZTE Research Group on Photoacoustic Spectroscopy H-6720 Szeged Hungary ELI-HU Non-Profit Ltd H-6720 Szeged Hungary Department of Earth and Environmental Sciences University of Pannonia P.O. Box 158 Veszprem H-8201 Hungary MTA-PE Air Chemistry Research Group P.O. Box 158 Veszprem H-8201 Hungary

A field measurement campaign was carried out during the late winter and early spring of2015 in Budapest, the capital of Hungary. The size distribution(SD) and optical absorption of carbonaceous particulate matter(CPM) was measured online using a Scanning Mobility Particle Sizer(SMPS), a 7λ-aethalometer and an inhouse developed 4λ-Photoacoustic Spectrometer. Based on the SD data, the measurement period could be classified into days with and without new particle formation events(normal days and nucleation days),although particular nucleation-like events were observed on normal days as well. Three characteristic size modes were observed with CMDs of circa 15, 25 and 110 nm that corresponded to the nucleation, traffic and heating modes. Based on the temporal behavior of these modes both types of days were divided into distinctive daily periods(heating hours,traffic hours and nucleation hours). The optical absorption spectra(OAC and AAE) also displayed the same part of day behavior to that of SD. That way this paper is among the first to assess the optical response of urban nucleation events. Due to the simultaneous measurement of OAC by the 7λ-aethalometer and a 4λ-Photoacoustic Spectrometer, OAC was measured overall at 11 wavelengths. That way aethalometer correction factors(f and C)were determined at all aethalometer wavelengths using in situ reference photoacoustic measurements. Correction factors were found to have both wavelength and time of the day variation. In the case of f, no clear trend could be observed, however, Cref values increased both as a function of wavelength.

关键词： Photoacoustic spectroscopy Aerosol Angstr?m exponent Aethalometer Nucleation Size distribution

Subsurface accumulation of CaCO3 and Cl- from groundwater under black locust and poplar plantations

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Journal of Forestry Research 2019年第4期30卷 1353-1361页

作者： Andras Szabo zoltan Gribovszki Esteban Gabriel Jobbagy Kitti Balog Andras Bidlo Tibor toth Forest Research Institute National Agricultural Research and Innovation CentreVarkeriilet 30/ASarvar 9600Hungary Institute of Geomatics and Civil Engineering Faculty of ForestryUniversity of SopronBajcsy-Zsilinszky u.4Sopron 9400Hungary Grupo de Estudios Ambientales-IMASL Universidad Nacional de San Luis&CONICETEjercito de ios Andes 950D5700HHW San LuisArgentina Institute for Soil Sciences and Agricultural Chemistry Centre for Agricultural ResearchHASHerman O u.15Budapest 1022Hungary Institute of Environmental and Earth Sciences Faculty of ForestryUniversity of SopronBajcsy-Zsilinszky u.4Sopron 9400Hungary

When conditions are similar,more water evaporates from forest plantations than herbaceous vegetation,thereby affecting hydrological fluxes and ion transport in the *** vertical distribution of CaCO3 and Cl^-ions shifts due to *** effect of groundwater depth and clay content were studied in the Great Hungarian Plain where forest area has been increasing for decades by analyzing soil and groundwater samples from stands of black locust(Robinia pseudoacacia,11 plots)and poplar(Populus spp.,11 plots).All study sites contained one herbaceous(control)and one or more forested ***3 and Cl^-ions accumulated in the soil profile in greater quantities under tree cover than in the *** scale of this process largely depended on the species and on soil and ion *** black locust,Cl^-accumulated between 1.3 and 6.3 m,with a maximum difference of 0.3 pCl unit(pCl is Cl^-activity,the negative of the logarithm to base 10 of the concentration of the chloride ion,determined using an ion-selective electrode,it is a dimensionless quantity.),while the difference in CaCO3 accumulation was at most 3.5%in some layers,compared to control *** result may be explained by the difference in the mobility of Ca+and Cl^-*** mechanisms were noticeable under poplar plantations due to their higher water uptake:Cl-accumulation was detected below 0.9 m to the groundwater with a maximum difference of 0.5 pCl units,while CaCO3 accumulation was continuous at depths of 2.3–6.8 m with a maximum difference of 8.4%,compared to the *** increasing clay content,there was a discernible effect on CaCO3 and Cl-accumulation under black locust,but not observed under *** differences were explained by the differences in water uptake mechanisms and root patterns of the two species and the different mobility of Ca2^+and Cl-ions.

关键词： Tree plantations Ion accumulation Water regime Water uptake strategy Root structure

Ranking parameters in urban energy models for various building forms and climates using sensitivity analysis

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建筑模拟(英文) 2023年第9期16卷 1587-1600页

作者： Aysegul Demir Dilsiz Kaitlynn Ng Jérôme Kämpf zoltan Nagy Department of Civil and Architectural Engineering and Construction Management University of WyomingLaramie WYUSA Intelligent Environments Lab Department of CivilArchitectural and Environmental EngineeringThe University of Texas at AustinAustin TXUSA Energy Informatics Group Idiap Research Institute1920 MartignySwitzerland

Urban Building Energy Modelling(UBEM)allows us to simulate buildings’energy performances at a larger ***,creating a reliable urban-scale energy model of new or existing urban areas can be difficult since the model requires overly detailed input data,which is not necessarily publicly *** calibration is a necessary step to reduce the uncertainties and simulation results in order to develop a reliable and accurate *** to the concerns over computational resources and the time needed for calibration,a sensitivity analysis is often required to identify the key parameters with the most substantial impact before the calibration is deployed in ***,we study the sensitivity of uncertain input parameters that affect the annual heating and cooling energy demand by employing an urban-scale energy model,*** goal is to determine the relative influence of each set of input parameters and their interactions on heating and cooling loads for various building forms under different ***,we conduct a global sensitivity analysis for annual cooling and heating consumption under different climate *** upon this,we investigate the changes in input sensitivity to different building forms,focusing on the indices with the largest Total-order ***,we determine First-order indices and Total-order effects of each input parameter included in the urban building energy *** also provide tables,showing the important parameters on the annual cooling and heating demand for each climate and each building *** find that if the desired calibration process require to decrease the number of the inputs to save the computational time and cost,calibrating 5 parameters;temperature set-point,infiltration rate,floor U-value,*** U-value and roof U-value would impact the results over 55%for any climate and any building form.

关键词： global sensitivity analysis Sobol’method urban energy modeling building stocks energy modelling parameter screening Sobol’indices sustainable urban planning

Real-world challenges for multi-agent reinforcement learning ingrid-interactive buildings

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能源与人工智能(英文) 2022年第4期10卷 161-170页

作者： Kingsley Nweye Bo Liu Peter Stone zoltan Nagy Intelligent Environments Laboratory Department of CivilArchitectural and Environmental EngineeringThe University of Texas at Austin301 E.Dean Keeton St.ECJ 4.200Austin78712-1700TXUSA Department of Computer Science The University of Texas at Austin2317 SpeedwayGDC 2.302Austin78712-1700TXUSA

Building upon prior research that highlighted the need for standardizing environments for building controlresearch, and inspired by recently introduced challenges for real life reinforcement learning (RL) control, herewe propose a non-exhaustive set of nine real world challenges for RL control in grid-interactive buildings(GIBs). We argue that research in this area should be expressed in this framework in addition to providing astandardized environment for repeatability. Advanced controllers such as model predictive control (MPC) andRL control have both advantages and disadvantages that prevent them from being implemented in real worldproblems. Comparisons between the two are rare, and often biased. By focusing on the challenges, we caninvestigate the performance of the controllers under a variety of situations and generate a fair comparison.

关键词： Grid-interactive buildings Benchmarking Reinforcement learning