نتایج جستجو برای: acoustic barriers

تعداد نتایج: 166440  

Journal: :international journal of environmental research 2010
h. mehravaran s. zabani gh.r. nabi bidhendi r. ghousi h. keshavarzi shirazi

the equivalent noise level in large cities has been growing due to the population growth, uncontrolled production of cars, and the existence of worn out cars. on the other hand, heavy traffic has increased the amount of noise problems for residents of medical and educational centers, research institutes and residential area (or sensitive centers to noise) built in highway bounds and it has also...

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Journal: :The Journal of the Acoustical Society of America 2007

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ژورنال: سلامت و محیط زیست 2010
منظم, محمد رضا, مومن بالله فرد, سمانه, نادرزاده, مهدیه, نصیری, پروین,

Backgrounds and Objectives: There is a considerable notice in the use of noise barriers in recent years. Noise barriers as a control noise solution can increase the insertion loss to protect receivers. This paper presents the results of an investigation about the acoustic efficiency of primitive root sequence diffuser (PRD) on environmental single T-shape barrier.Materials and Methods: A 2D bou...

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Journal: :The Journal of the Acoustical Society of America 1974

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Journal: :Akustika 2019

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1994
J. Czyzowicz E. Rivera-Campo N. Santoro J. Urrutia J. Zaks

Consider a rectangular art gallery divided into n rectangular rooms, such that any two rooms sharing a wall in common have a door connecting them. How many guards need to be stationed in the gallery so as to protect all of the rooms in our gallery? Notice that if a guard is stationed at a door, he will be able to guard two rooms. Our main aim in this paper is to show that Èn/2 ̆ guards are alway...

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Journal: :MATEC Web of Conferences 2020

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Journal: :Journal of Wind Engineering and Industrial Aerodynamics 2019

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پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تبریز - دانشکده کشاورزی 1394
مینا غلامی, حسین راحلی, شاپور ظریفیان,

with the increasing population and the need for more food, as well as with the development of science and technology, human approach to unnatural and often chemical inputs to increase agricultural production has been a great expansion and problems such as increased cancers, chronic diseases has created environmental pollution. implementation of organic organic is a solution to these problems . ...

Journal: :MATEC Web of Conferences 2020

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نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید

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