Search results for " DRIP"

Tapered drip laterals and manifolds in flat and rectangular irrigation units

2023

Multiple-diameter laterals and manifolds reduce the total cost in microirrigation systems, however, the length of each sublateral should be determined carefully to assure appropriate performance and uniformity of emitter flow rates. The most accurate method is numerical trial and error, which is time-consuming. Many research efforts have been made to propose simple analytical design procedures. By using the power-law form of the Darcy-Weisbach formula, and equal emitters spacing for the sublaterals, Sadeghi et al. (2016) extended a previously introduced design solution for one-diameter laterals to tapered laterals. Recently, a simplified procedure to design dual-diameter drip laterals has b…

A new record of the desert truffle Picoa lefebvrei in Saudi Arabia

2012

A new record of Picoa lefebvrei from Saudi Arabia is reported accompanied by notes on its taxonomy, ecology, and distribution.

Striking a Balance among Security, Privacy and Competition. The Data Retention and Investigatory Powers Act 2014 (DRIP)

2015

Following the ECJ decision that declared the Data Retention Directive invalid, the Data Retention and Investigatory Powers Act 2014 (DRIP) has been enacted. It is not indisputable whether the DRIP gives more powers to the intelligence services at the detriment of both citizens’ privacy and freedom of enterprise or whether it simply clarifies the nature and extent of obligations that can be imposed on telecommunications service providers based outside the UK under Part 1 of the Regulation of Investigatory Powers Act 2000 (RIPA). The article provides news also on Data Retention Regulations 2014, R (David Davis MP and Tom Watson MP) v Secretary of State for the Home Department and the proposed…

Advances in designing drip irrigation laterals

2018

It is known that using paired laterals, in which two distribution pipes extend in opposite directions from a common manifold, contribute to increasing water use efficiency (WUE). Recently, an analytical procedure to optimally design paired drip laterals on uniform slopes was proposed. More recently, this design procedure was simplified by deriving simple explicit relationships, as a function of 16 calibration constants, with relative errors that were less than 2%. In this paper, further simple design relationships are derived that require only 3 calibration constants, thus more readily obtainable results are produced and the influence of the flow rate and diameter exponents of resistance eq…

Experimental Tests to Validate a Simple Procedure to Design Dual-Diameter Drip Laterals on Flat Fields

2023

Multiple-diameter laterals reduce the total cost in microirrigation systems, however, the length of each sublateral should be determined carefully to assure appro-priate performance of emitter flow rates. The most accurate method is the numerical trial and error, which is time-consuming. A series of research efforts have been made to propose simple analytical design procedures. By using the power-law form of the Darcy-Weisbach formula, and equal emitters spacing for the sublaterals, Sadeghi et al. (Sadeghi et al. in J Irrig Drain E-ASCE 142:04,016,020, 2016) extended a previously introduced design solution for one-diameter laterals to tapered laterals. Recently, a simplified procedure to de…

Effetti dell’uso di acque reflue urbane depurate sugli apparecchi erogatori

2005

A Comprehensive Model for Hydraulic Analysis and Wetting Patterns Simulation under Subsurface Drip Laterals

2022

In the absence of suitable specialized models to simulate the soil wetting patterns in subsurface drip irrigation systems considering the hydraulic conditions along the laterals, a new model was developed and named a “comprehensive model” in this study. This model couples the subsurface drip irrigation lateral characteristics with the soil hydraulic properties and utilizes the Hydrus-3D software as a complementary section of the model to simulate the wetting front beneath the lateral. To evaluate the model, three 16 mm drip-line pipes of 62 m length with 20, 40, and 50 cm spacing emitters and 2 to 5 L/h discharge were buried at 0.2 m depth in a soil box containing clay loamy soil. Then, the…

α decay of the πh11/2 isomer in Ir164

2014

The α -decay branch of the πh 11 / 2 isomer in 164 Ir has been identified using the GREAT spectrometer. The 164 Ir nuclei were produced using the 92 Mo( 78 Kr ,p 5 n ) 164 Ir reaction and separated in flight using the recoil ion transport unit (RITU) gas-filled separator. The measured α -decay energy of 6880 ± 10 keV allowed the excitation of the πh 11 / 2 state in 160 Re to be deduced as 166 ± 14 keV. The half-life of 164 Ir was measured with improved precision to be 70 ± 10 μ sandan α -decay branching ratio of 4 ± 2% was determined. Improved half-life and branching ratio measurements were also obtained for 165 Ir, but no evidence was found for the ground-state decays of either 164 Ir or 1…

Assessing HYDRUS-2D model to simulate water content and salt accumulation in a soil irrigated with a subsurface drip system: Application in a semiari…

2015

In this paper, the suitability of HYDRUS-2D model to predict the average soil water content in the root zone of potato crop irrigated with subsurface drip irrigation plant, is initially assessed on the basis of a field study. Then, the model is tested to predict the salt distribution around a buried emitter, when two different water qualities (i.e. electrical conductivity of 1.0 dS m-1 and 4.0 dS m-1), are used during the growing season (treatments T1 and T2). Finally, the soil volume in which salts accumulates, as well as the effects on crop yield is recognized for both the considered treatments.The results evidenced that predicted values of average soil water content in the root zone were…