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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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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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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

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

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。

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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

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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

Long term sediment transport simulation of the Danube,Sava,and Tisa rivers

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International Journal of Sediment Research 2020年第5期35卷 550-561页

作者： Mirjana Horvat zoltan Horvat University of Novi Sad Faculty of Civil Engineering Subotica

The aim of this paper is to evaluate a newly developed one dimensional unsteady flow,sediment transport and bed evolution model for a looped river network through a long term simulation of a reallife *** model was assessed by verifying it for the Danube,Tisa,and Sava rivers in Serbia for a five year time *** total length of the modeled domain was 741.94 km from which 486.48 km is the length of the modeled Danube River reach,132.50 km the modeled section of the Sava and 122.96 km the length of the modeled Tisa River *** simulated domain included smaller tributaries such as the Kolubara,Mlava,Nera,Pek,Porecka,Tamis,and Great Morava *** to the size of the domain that was included in the model,the work also includes extensive research regarding the available measurements,issues with measurement errors,and suggestions on overcoming incomplete measurements by developing different types of *** attained results were analyzed by comparing the simulation results with measured water levels,discharges,and suspended sediment *** implemented evaluation of the results confirmed the developed model's reliability.

关键词： 1-D sediment transport Looped river network Long term simulation Calibration Verification

Enhanced Photocatalytic Activity of TiO2 Nanofibers and Their Flexible Composite Films： Decomposition of Organic Dyes and Efficient H2 Generation from Ethanol-Water Mixtures

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Nano Research 2011年第4期4卷 360-369页

作者： Ming-Chung Wu Andras Sapi Anna Avila Maria Szabo Jussi Hiltunen Mika Huuhtanen Geza toth Akos Kukovecz zoltan Konya Riitta Keiski Wei-Fang Su Heli Jantunen Krisztian Kordas Department of Electrical and Information Engineering University of Oulu P.O. Box 4500 FI-90014 University of Oulu Finland Department of Applied and Environmental Chemistry University of Szeged 6720 Szeged Rerrich Bela ter 1 Hungary Department of Process and Environmental Engineering P.O. Box 4300 F1-90014 University of Oulu Finland Department of Materials Science and Engineering National Taiwan University Taipei 106-17 Taiwan China

TiO2 nanofibers decorated with Pt and Pd nanoparticles have been synthesized and studied in various photocatalytic processes. Excellent photocatalytic behavior in the decomposition of organic dyes in water, degradation of organic stains on the surface of flexible freestanding cellulose/catalyst composite films and in generation of hydrogen from ethanol using both suspended and immobilized catalysts are demonstrated. The performance of the nanofiber-based TiO2 materials is competitive with and in some cases outperforms--their conventional nanoparticle-based counterparts. In all cases, Pd-decorated TiO2 nanoparticles and nanofibers proved to be more efficient than their Pt-based counterparts, which could be explained on the basis of the formation of nano-sized Schottky interfaces at the contacts between TiO2 and metal nanoparticles. The feasibility of forming cellulose/catalyst composites provides a novel way of utilizing photocatalyst materials in large-area coatings and freestanding films.

关键词： TiO2 photocatalyst metal-decorated TiO2 nanowires H2 generation oxidation of organic dyes