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An Impact of Hydrostatic Extraction Scheme on BMRC's Global Spectral Model

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Advances in Atmospheric Sciences 1992年第3期9卷 269-278页

作者：盛华 william Bourke Terry hart Institute of Atmospheric Physics Academia Sinica Beijing Australian Bureau of Meteorology Research Centre Australian Bureau of Meteorology Research Centrehere are two important features in geophysical fluid dynamics. One is that the atmospheric and oceanic equations of motion include the Coriolis force another is that they describe a stratified fluid. The hydrostatic extraction scheme or standard stratification approximation posed by Zeng (1979) reflects the second aspect of geophysical fluid dynamics. There exist two major advantages in this scheme accurate computation of the pressure gradient force can be obtained over steep mountain slopes and the accumulation error in vertical finite differencing can be reduced especially near the tropopause.Chen et al (1987) introduced the hydrostatic extraction scheme into a global spectral model which attained preliminary success at low resolution. Zhang and Sheng et al (1990) developed and improved the hydrostatic extraction scheme in a global spectral model in which C0 the parameter that represents the stratification of the reference atmosphere changes not only with height but also with latitude. The scheme has been incorporated BMRC's global spectral model (IAPB). Four 5-day forecasts have been performed to test the IAPB with the hydrostatic extraction scheme. Objective verifications demonstrate a positive effect of the hydrostatic extration scheme on BMRC's model particularly at upper levels over the tropics and the Antartic region.

There are two important features in geophysical fluid dynamics. One is that the atmospheric and oceanic equations of motion include the Coriolis force; another is that they describe a stratified fluid. The hydrostatic extraction scheme, or standard stratification approximation, posed by Zeng (1979), reflects the second aspect of geophysical fluid dynamics. There exist two major advantages in this scheme; accurate computation of the pressure gradient force can be obtained over steep mountain slopes, and the accumulation error in vertical finite differencing can be reduced, especially near the *** et al (1987) introduced the hydrostatic extraction scheme into a global spectral model, which attained preliminary success at low resolution. Zhang and Sheng et al (1990) developed and improved the hydrostatic extraction scheme in a global spectral model, in which C0, the parameter that represents the stratification of the reference atmosphere, changes not only with height, but also with latitude. The scheme has been incorporated BMRC's global spectral model (IAPB). Four 5-day forecasts have been performed to test the IAPB with the hydrostatic extraction scheme. Objective verifications demonstrate a positive effect of the hydrostatic extration scheme on BMRC's model, particularly at upper levels, over the tropics and the Antartic region.

关键词： An Impact of Hydrostatic Extraction Scheme on BMRC’s Global Spectral Model

Spatio-temporal analysis of flowering using Li DAR topography

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Journal of Geographical Sciences 2017年第1期27卷 62-78页

作者： hart Samantha MIkHAILOVA Elena POST Christopher Mc MILLAN Patrick SHARP Julia BRIDGES william Department of Forestry and Environmental Conservation Clemson University SC 29634 USA Department of Mathematical Sciences Clemson University SC 29634 USA

Spatio-temporal patterns of flowering in forest ecosystems are hard to quantify and monitor. The objectives of this study were to investigate spatio-temporal patterns（e.g. soilssimple slope classesslope aspectand flow accumulation） of flowering around Lake IssaqueenaSouth Carolina（SCUSA） using plant-flowering database collected with GPS- enabled camera（stored in Picasa 3 web albums and project website） on a monthly basis in 2012 and Li DAR-based topography. Pacolet fine sandy loam had the most flowering plantsfollowed by Madison sandy loamboth dominant soil types around the lake. Most flowering plants were on moderately steep（17%–30%） and gently sloping（4%–8%） slopes. Most flowering plants were on west（247.5°–292.5°）southwest（202.5°–247.5°）and northwest（292.5°–337.5°） aspects. Most flowering plants were associated with minimum and maximum flows within the landscape. Chi-square tests indicated differences in the distributions of the proportions of flowering plants were significant by soil typeslopeaspectand flow accumulation for each month（February-November）for all months（overall）and across months. The Chi-square test on area-normalized data indicated significant differences for all months and individual differences by each month with some months not statistically significant. Cluster analysis on flowering counts for nine plant families with the most flowering counts indicated no unique separation by clusterbut implied that the majority of these families were flowering on strongly sloping（9%–16%） slopeson southwest（202.5°–247.5°） aspectsand low flow accumulation（0–200）. Presented methodology can serve as a template for future efforts to quantify spatio-temporal patterns of flowering and other phenological events.

关键词： aspect flow accumulation Geographic Information Systems(GIS) phenology soils

Engineering electromagnetics = 工程电磁场 7th ed.

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Engineering electromagnetics / 7th ed. 7th ed.

丛书名：清华版双语教学用书

2009年

作者： Hayt william hart

本书基本概念讲述清晰, 注重物理概念, 淡化公式推导, 强调自主学习, 图文并茂 ; 每章后面配有大量习题。配书光盘提供了彩色场图、动画、问答测试题和关键内容的交互式学习, 内容丰富, 适子自学。

ISBN: (数字)9787302204077

ISBN: (纸本)9787894745958

关键词： Electromagnetic theory.

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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Disturbance history,species diversity,and structural complexity of a temperate deciduous forest

丛书名： McGraw-Hill series in electrical engineering.

2006年

作者： Hayt, william hart,

来源：畅想之星图书光盘版（南... 评论

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Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan D.Goode Carson R.Barefoot Justin L.hart Daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand structural complexity enhancement is an increasingly popular management objective,especially on public *** stand structures are hypothesized to support a relatively high degree of native forest diversity and be more resistant and resilient to *** structures are characterized by the presence of deadwood and heterogeneity of tree-size classes and tree *** little is known about how discrete disturbance events affect structural complexity and compositional diversity in Quercus-dominated stands at fine spatial scales(***).We established 200.05 ha fixed-radius plots on the Sipsey Wilderness of william *** National Forest in northern Alabama to quantify woody plant species composition and *** were mapped on each plot to quantify overstory structural complexity and compositional *** extracted two cores from all canopy Quercus spp.C 5 cm diameter at breast height to quantify age,recruitment pulses,and reconstruct canopy disturbance *** species diversity in the sampled area was 1.75 for trees,2.08 for saplings,and 1.69 for *** alba had the greatest basal area,and Ostrya virginiana had the highest *** stand exhibited a reverse J-shaped distribution with a q-factor of *** oldest Quercus dated to 1795,and the largest recruitment pulse occurred in the *** mean return interval for intermediateseverity disturbance was 38 *** we documented no relationships between disturbance frequency and compositional diversity at the neighborhood scale(0.05 ha),less frequent disturbance was associated with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood *** suggest that localized disturbance increases species diversity and structural complexity,but these processes are manifest at the stand level and not at the neighborhood *** conclude that the spatial variability(***,shape,orientation,microsite conditions)is likel

关键词： Canopy gap Quercus(oak) Stand development Succession

Sensitivity of the CLM 4.0 （Community Land Model Version 4.0） to key Modeling Parameters and Modeling of key Physical Processes with Focus on the Arctic Environment

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Journal of Geological Resource and Engineering 2014年第1期2卷 39-54页

作者： Elena A. kalinina william J. Peplinski Vincent C. Tidwell David B. hart Sandia National Laboratories Albuquerque 87185 NM USA

The CLM （Community Land Model） simulates major physical processes at the land surface and in the shallow subsurface and calculates the parameters that are then used as the inputs into the atmospheric model. The major goal of this study was to identify the parameters that have greatest impacts on these inputs and thus, the greatest potential to impact the climate in Arctic environment. Another goal was to identify the limitations in representing different physical processes and to determine whether these limitations restrict the ability of CLM to predict the distribution of energy at the land surface. The focus of this analysis is on the vegetation and soil models. The analysis was conducted for a grid cell near Fairbanks, Alaska. A range of hydrogeologic and thermal soil properties and vegetation characteristics was defined for the vegetation and soil parameters. Multiple CLM sensitivity runs were performed. The sensitivity cases that produced noticeable differences either between the mean soil temperatures or/and between ground temperatures were the cases related to the LAI （leaf area index）, SAI （stem area index）, and soil moisture （shallow water table conditions）. These results were explained based on the analysis of the net radiation partitioning at the land surface.

关键词： Soil moisture soil temperature vegetation properties ground heat latent heat sensible heat.

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海洋环境安全:一种可持续发展的观点

厦门大学学报（自然科学版） 2004年第B08期43卷 254-257页

作者：张珞平洪华生陈伟琪刘泓 william C.hart 厦门大学海洋环境科学教育部重点实验室环境科学研究中心福建厦门361005 福建农业与林业大学资源与环境学院福建福州361005 加拿大Dalhousie大学水资源研究中心 NSB3J2X4Canada

联合国海洋环境保护科学问题联合专家组(GESAMP)是一个由八个联合国机构发起的科学顾问团体,它的报告和述评是各个联合国组织制定有关海洋政策和决策的基础.尽管GESAMP的观点近年来有很大进展,但在如何促进和改善保护海洋环境的行动等... 详细信息

联合国海洋环境保护科学问题联合专家组(GESAMP)是一个由八个联合国机构发起的科学顾问团体,它的报告和述评是各个联合国组织制定有关海洋政策和决策的基础.尽管GESAMP的观点近年来有很大进展,但在如何促进和改善保护海洋环境的行动等问题仍有它的局限性.本文提出了"海洋环境安全"的概念,以促进海洋环境保护和海洋资源的可持续利用,并讨论了海洋环境研究和海洋环境管理应采取的行动.

关键词：海洋环境安全可持续发展海洋污染海洋环境保护持续性原则海洋资源

从“毒刺”到“中后卫”——“布雷德利”战车更新防空系统

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国外坦克 1998年第2期 18-21页

作者： william D.hart Jr 孙忠敏

布雷德利“中后卫”防空系统,已于1996年11月获准投入批量生产。现已有8套系统装备到驻德克萨斯州胡德堡的第4机步师第44防空炮兵部队第一营。该营是陆军特遣部队21世纪先进作战实验室的实验单位。

关键词：防空系统作战实验室特遣部队防空炮系统装备毒刺批量生产战车实验单位步师

膝关节多发韧带损伤的手术时机选择和术后功能锻炼的系统性综述

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中华骨科杂志 2010年第3期30卷 I0024-I0033页

作者： william R.Mook, MD Mark D.Miller, MD David R. Diduch, MD JayHertel, PhD ATC, Yaw Boachie-Adjei, MD Joseph M.hart, PhD, ATC 韦祎(译) 冯华(译) 0Investigation performed at the Department of Orthopaedic Surgery University of Virginia Health System Charlottesville Virginia 北京积水潭医院运动损伤科 100035

背景：膝关节外伤性脱位导致的多发韧带损伤并不常见，相关研究也较少。由于缺乏前瞻性数据资料，所以对于手术时机选择以及术后康复方案的选择仍存在争议。本篇综述旨在对比早期、延期和分期手术的结果以及各种康复方案的疗效。方法：... 详细信息

背景：膝关节外伤性脱位导致的多发韧带损伤并不常见，相关研究也较少。由于缺乏前瞻性数据资料，所以对于手术时机选择以及术后康复方案的选择仍存在争议。本篇综述旨在对比早期、延期和分期手术的结果以及各种康复方案的疗效。方法：收集检索24篇回顺性研究，共计396个膝关节，侧重于严重多发韧带损伤的外科治疗。韧带损伤包括前、后十字韧带和（或）内单侧或内外双侧副韧带。数据采集后，按照手术时间（早期、延期和分期）将患者分组。同时我们也将术后早期功能锻炼和术后制动进行对比。

关键词：膝关节多发韧带损伤术后功能锻炼系统性综述手术时机早期功能锻炼膝关节外伤性脱位术后康复方案分期手术