نتایج جستجو برای: asce penman

تعداد نتایج: 1900  

ژورنال: علوم آب و خاک 2014

It is necessary that ETr (Alfalfa-reference evapotranspiration) values be converted to ETo (Grass-reference evapotranspiration) or vice versa. The main objective of this study was to develop ETr to ETo ratios (Kr values) for a growing season in Shahrekord plain, Shahrekord, Iran. Mean monthly and total (growing season) values of Kr were calculated based on 185 daily ET data set in Chaharthakhte...

Journal: :آب و خاک 0
بختیاری بختیاری خلیلی خلیلی لیاقت لیاقت خانجانی خانجانی

abstract in recent years, automatic weather stations have been widely used for recording meteorological data in different time scales. therefore the accurate estimation of eto by combination equations can be evaluated using these set of short time scales data. daily eto can also be calculated by summation of hourly eto values. the purpose of this study is to compare the eto values estimated by ...

ژورنال: علوم آب و خاک 2010
بختیاری, بهرام, خانجانی, محمدجواد, خلیلی, علی, لیاقت, عبدالمجید,

In this study, the Penman-Monteith methods proposed by the Food and Agriculture Organization (FAO-56) and American Society of Civil Engineers (ASCE) were used for hourly ETo estimation under the semiarid climate of Kerman, Iran. Hourly ETo estimations obtained from the proposed methods were compared with measured ETo values by using a large weighing electronic lysimeter during April to Septembe...

2002
George H. Hargreaves Richard G. Allen

A brief history of development of the 1985 Hargreaves equation and its comparison to evapotranspiration ~ET! predicted by the Food and Agricultural Organization of the United Nations ~FAO! Penman-Monteith method are described to provide background and information helpful in selecting an appropriate reference ET equation under various data situations. Early efforts in irrigation water requiremen...

Journal: :آب و خاک 0
زهرا شیرمحمدی علی اکبر خانی حسین انصاری امین علیزاده

abstract potential evapotranspiration is one of basic parameter in hydrologic cycle that should be estimate in irrigation design and scheduling, watershed hydrology studies. many applications in diverse disciplines require estimates of evapotranspiration (et) at hourly or smaller time steps. the primary objectives of this study were to compare the american society of civil engineers (asce) and ...

J. Sajad M. Farasati O. Bahmani S. M. Seyedian

ABSTRACT-Different evapotranspiration (ET) estimation equations having different accuracy with different conditions have been developed for ET estimation. This study will firstly focus on the estimation of 13 climatic equations of daily garlic ET estimation whose  ET is measured by lysimeter to provide information which can be helpful in selecting an appropriate ET equation. The paper aims at s...

Journal: :iran agricultural research 2016
s. m. seyedian m. farasati o. bahmani j. sajad

abstract-different evapotranspiration (et) estimation equations having different accuracy with different conditions have been developed for et estimation. this study will firstly focus on the estimation of 13 climatic equations of daily garlic et estimation whose  et is measured by lysimeter to provide information which can be helpful in selecting an appropriate et equation. the paper aims at s...

1994
Keith Vander Linden

This study employs a knowledge intensive corpus analysis to identify the elements of the communicative context which can be used to determine the appropriate lexical and grammatical form of instructional texts. imagene, an instructional text generation system based on this analysis, is presented, particularly with reference to its expression of precondition relations.

Journal: :journal of agricultural science and technology 2011
b. bakhtiari a. m. liaghat

seasonal variations of climatic parameters are significant in arid and semi-arid regions and sensitivity of each parameter may differ in different seasons. no work has been done in this regard in iran. therefore, in this study, sensitivity analysis of the asce-penman-monteith grass reference evapotranspiration (eto) equation was investigated on the basis of variation of mean air temperature (tm...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید