نتایج جستجو برای: roughness survey

تعداد نتایج: 393512  

Journal: :international journal of civil engineering 0
h. behbahani s.m. elahi

to properly plan for construction, repair, maintenance, and reconstruction of highways the minimum acceptable roadway condition is needed information. this, along with other pavement management tools, will help select the most desirable roadway alternatives. in this research the minimum acceptable conditions are developed based on an opinion survey of non-technical but high-level decision maker...

Journal: :Remote Sensing 2015
Xin Tian Christiaan van der Tol Zhongbo Su Zengyuan Li Erxue Chen Xin Li Min Yan Xuelong Chen Xufeng Wang Xiaoduo Pan Feilong Ling Chunmei Li Wenwu Fan Longhui Li

We propose a long-term parameterization scheme for two critical parameters, zero-plane displacement height (d) and aerodynamic roughness length (z0m), that we further use in the Surface Energy Balance System (SEBS). A sensitivity analysis of SEBS indicated that these two parameters largely impact the estimated sensible heat and latent heat fluxes. First, we calibrated regression relationships b...

2000
Cheng-I Hsieh Gabriel Katul

An approximate analytical model was developed to estimate scalar ̄ux footprint in thermally strati®ed atmospheric surface layer ̄ows. The proposed model was based on a combination of Lagrangian stochastic dispersion model results and dimensional analysis. The main advantage of this model is its ability to analytically relate atmospheric stability, measurement height, and surface roughness length...

2005
M. Kardous

Wind erosion in agricultural soils is dependent, in part, on the aerodynamic roughness length (z0) produced by tillage ridges. Although previous studies have related z0 to ridge characteristics (ridge height (RH) and spacing (RS)), these relationships have not been tested for tillage ridges observed in the North African agricultural fields. In these regions, due to climate and soil conditions, ...

Journal: :Remote Sensing 2015
Qiting Chen Li Jia Ronald Hutjes Massimo Menenti

Most land surface models require information on aerodynamic roughness length and its temporal and spatial variability. This research presents a practical approach for determining the aerodynamic roughness length at fine temporal and spatial resolution over the landscape by combining remote sensing and ground measurements. The basic framework of Raupach, with the bulk surface parameters redefine...

Journal: Desert 2016
Afshin Jahanshahi, Ali Afzali, Mohammad Golshan

Development of rural areas in rivers margins and flood plains, without understanding and attention to the dynamical and hydrological conditions and upstream areas of the rivers will cause to increase flood risk and loss of life and financial. Flood zoning has many applications, in floodplain management. For management of the three major branches of the Halilrood River, Rabor, Roodar and Javaran...

2017
S. Jeevanantham N. M. Sivaram N. Manikanda Prabu

Internal Grinding is an approach to produce desired outcome with greater surface finish in metal cutting process. Unfortunately, external machining parameters play a vital role in research areas with numerous investigations. Considering this, present work focuses on the machining parameters on internal grinding process with necessary coolant oil as has been experimentally observed in our resear...

2007
H. Löwe L. Egli S. Bartlett M. Guala C. Manes

[1] The deposition and attachment mechanism of settling snow crystals during snowfall dictates the very initial structure of ice within a natural snowpack. In this letter we apply ballistic deposition as a simple model to study the structural evolution of the growing surface of a snowpack during its formation. The roughness of the snow surface is predicted from the behaviour of the time depende...

2003
N. PINEDA J. M. BALDASANO

The mesoscale numerical weather prediction model MM5, the 5 generation Pennsylvania State University/NCAR Mesoscale Model, uses a global land-use map to set the physical parameters on the surface characteristics to model the soil-atmosphere processes. These parameters are albedo, emissivity, thermal inertia, roughness length and soil moisture. A new estimation of soil parameters is done for the...

Journal: :Remote Sensing 2017
Etienne Cheynet Jasna B. Jakobsen Jónas Snæbjörnsson Jakob Mann Michael Courtney Guillaume Lea Benny Svardal

Three synchronized pulsed Doppler wind lidars were deployed from May 2016 to June 2016 on the shores of a wide Norwegian fjord called Bjørnafjord to study the wind characteristics at the proposed location of a planned bridge. The purpose was to investigate the potential of using lidars to gather information on turbulence characteristics in the middle of a wide fjord. The study includes the anal...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید