نتایج جستجو برای: water leakage

تعداد نتایج: 578911  

Journal: :نشریه مهندسی عمران و نقشه برداری 0
امیرحسین اسدیانی یکتا دانشگاه آزاد اسلامی مسعود تابش دانشگاه تهران

leakage in water distribution networks causes waste of water and economical losses. in this paper a new method is presented to calculate nodal and pipes leakage in water distribution systems using capabilities of epanet2.10 software. the method estimate the total water losses in the system based on iwa methodology using minimum night flow (mnf) measurements. recognising the pressure dependency ...

ژورنال: علوم آب و خاک 2017

The water supply networks have always been of significance to researchers as a hydraulic system of transferring and distributing water. The pressure gradient is the main reason of water transfer in networks, and in case of non-standard pressure increase, the undesirable phenomenon of leakage occurs in the network. Leakage in urban water distribution networks causes water waste and enormous fina...

Journal: :تحقیقات مهندسی کشاورزی 0
محمد موحدان محقق موسسه تحقیقات فنی و مهندسی کشاورزی

iran has limited water resources that require preservation and reducing water loss from reservoirs, especially in arid and semi arid regions. there are a number of methods available for to control water loss from reservoirs and canals. concrete linings in water reservoirs and ponds are durable, but their efficiency is limited. geomembrane sheets are another method of controlling leakage from wa...

Jin liang Gao Juanjuan Li Jun Nan Shi hua Qi

The economic and environmental losses due to serious leakage in the urban water supply network have increased the effort to control the water leakage. However, current methods for leakage estimation are inaccurate leading to the development of ineffective leakage controls. Therefore, this study proposes a method based on the blind source separation theory (BSS) to calculate the leakage of water...

Journal: :تحقیقات نظام سلامت 0
حمیدرضا تشیعی دکتری مهندسی بهداشت محیط، شرکت مهندسی آب و فاضلاب کشور، تهران، ایران. مهدی حاجیان نژاد دانشیار، مرکز تحقیقات محیط زیست، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران محمدمهدی امین دانشیار، مرکز تحقیقات محیط زیست، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران. فرهام کرکانی کارشناس ارشد مهندسی بهداشت محیط، عضو بنیاد ملی نخبگان، تهران، ایران.

background: various chemicals are used to produce polymers ,leakage of polymer materials over the time , can cause health problems the aim of this research was to evaluate the leakage of heavy metals from the pvc and polypropylene pipes used in the water distribution system in isfahan. methods: four brands of pp pipes and two various types of pvc pipes were analyzed in this study. concentration...

Akbarpour , A., Khorashadizadeh, S., Majidi Khalilabad, N., Mollazadeh, M.,

Leakage detection in water distribution systems play an important role in storage and management of water resources. Therefore, to reduce water loss in these systems, a method should be introduced that reacts rapidly to such events and determines their occurrence time and location with the least possible error. In this study, in order to determine position and amount of leakage in distribution ...

Journal: :تحقیقات نظام سلامت 0
مهربان صادقی دانشیار، گروه مهندسی بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی شهرکرد، شهرکرد، ایران امین تاجی اشکفتکی دانشجوی کارشناسی ارشد، گروه مهندسی عمران، دانشکده فنی مهندسی، دانشگاه آزاد اسلامی واحد یاسوج، یاسوج، ایران حسن هاشمی کمیته تحقیقات دانشجویی، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران سعید حسینی مربی، گروه عمران، دانشکده فنی مهندسی، دانشگاه آزد اسلامی واحد یاسوج، یاسوج، ایران

abstract background: the pressure of consumption spots in eater supply systems is one of the most important hydraulic parameters can be used in optimized management of water distribution networks. since the pressure has some different effects on various parameters of the network management including its hydraulic functions, reliability, stability and leakage, its control is of great importance ...

Journal: :Ground water 2008
Angelika C Braunsfurth Wilfried Schneider

The calculation of ground water transit times is one important factor in ground water protection. In this paper, we present an analytical solution for the transit time for a Dupuit-type flow system applicable to saturated flow through a horizontal leaky aquifer discharging to a downgradient fixed-head boundary under steady-state conditions. We investigate the influence of leakage when comparing...

1999
Paul V. Johnson

ost people consider unaccounted-for water and leakage to be the same thing. They are not. Leakage is a part, and sometimes a large part, of unaccounted-for water, but it is just one piece of the puzzle. Unaccounted-for water is the difference between the amount of water produced, or purchased, and the amount of water sold to all customers. Unaccounted-for water includes underground leakage; una...

Journal: :Tree physiology 1997
F J Bigras

Root systems of 6-month-old, cold-hardened, container-grown black spruce seedlings (Picea mariana (Mill.) B.S.P.) were exposed to 0, -5, -10, -15, -20, or -22.5 degrees C. Freezing-induced damage to fine roots, coarse roots and the whole root system was assessed by various viability tests including leakage of electrolytes, leakage of phenolic compounds, water loss, root and shoot water potentia...

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