نتایج جستجو برای: sound pressure load

تعداد نتایج: 643260  

Journal: :IEEE Transactions on Electrical Insulation 1989

ژورنال: اقیانوس شناسی 2022

Background and Objectives: Influence of water mass on sound propagation in the Gulf of Aden underwater acoustics used for communication, navigation and identification of objects by both humans and marine mammals and for investigating the detrimental effects of anthropogenic activities (e.g. pile driving, seismic survey and ships) on marine animals. The Gulf of Aden presents a unique ecosystem t...

ژورنال: سلامت کار ایران 2016

Background and aims: Development of new air pollution control techniques have always been the main concern of the researchers. The purpose of this experimental study was to investigate the effects of using acoustic fields at high sound pressure levels on the removal of sulfuric acid mist from the air stream. Methods: In this experimental study, an experimental scale agglomeration chamber was...

ژورنال: سلامت و محیط زیست 2011
اصلانی, حسن, قنبری, محمد, مسافری, محمد, ندافی, کاظم, یونسیان, مسعود,

Background and Objectives: Over the last three decades environmental pollutions became a more noticeable problem in all around of the world. In many countries, noise pollution as a basic problem has a great importance.Development of the city, increasing of industrial centers, increasing vehicles, other annoying noise resources and also little information about the noise pollution of Tabriz city...

2009
Koji Inui Tomokazu Urakawa Koya Yamashiro Naofumi Otsuru Yasuyuki Takeshima Ryusuke Kakigi

The cortical mechanisms underlying echoic memory and change detection were investigated using an auditory change-related component (N100c) of event-related brain potentials. N100c was elicited by paired sound stimuli, a standard followed by a deviant, while subjects watched a silent movie. The amplitude of N100c elicited by a fixed sound pressure deviance (70 dB vs. 75 dB) was negatively correl...

Journal: :The Journal of the Acoustical Society of America 1954

Journal: :تحقیقات نظام سلامت 0
حسینعلی یوسفی هیأت علمی، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، ایران فرهاد فروهرمجد هیأت علمی، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، ایران سمیه بلقن آبادی دانشجوی کارشناسی ارشد گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، ایران

abstract background: given the fact of irrecoverable consequences of noise in industrial societies and the environment, acoustic filter (silencer) is an instrument which obstacles the transmission of sound waves. a sort of this silencer is helmholtz resonator (branch amplifier) which comes to sound appropriate for low and below 200 hz frequencies in fan and channel noise. the purpose of this ar...

دهقانی, منصوره, زمانیان, زهرا, ساتیاروند, مصطفی, ناصرپور, مهسا,

Introduction: Agriculture is one of the oldest jobs in the world and almost 7-2 billion people all over the world are working in this field. In the field of agriculture workers may be always in danger, due exposure to various chemical and physical factors. Despite the dramatic technological developments in agricultural science, this field is still among one of the most dangerous workplaces...

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