نتایج جستجو برای: noise level

تعداد نتایج: 1250460  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس 1389

growing demands and requires of high data rate systems cause significant increase of high frequency systems for wideband communication applications. as mixers are one of the main blocks of each receivers and its performance has great impact on receiver’s performance; in this thesis, a new solution for ku-band (12-18 ghz) mixer design in tsmc 0.18 µm is presented. this mixer has high linearity a...

خاکی, علی منصور, فروهید, امیراسماعیل,

Introduction: Safe driving requires the ability of the driver to receive the messages and complying with them. The most significant consequences of noise pollution are on the human auditory system. Disorders in the auditory system can have harmful side effects for human health. By reducing this kind of pollution in large cities, the quality of life, which is one of the biggest goals of the gove...

Journal: :iranian journal of medical physics 0
sh. olumi m.sc. in medical physics, tarbiat modarres university, tehran, iran h. rajabi assistant professor, medical physics dept., tarbiat modarres university, tehran, iran s.r. zakavi associate professor, nuclear medicine dept., imam reza hospital, mashhad university of medical sciences, mashhad, iran e. hajizade associate professor, biostatistics dept., tarbiat modarres university, tehran, iran h. ghiasi m.sc. in medical physics, torfe hospital, tarbiat modarres university, tehran, iran

introduction: one of the major problems in the development of nuclear medicine images is the presence of noise. the noise level in nuclear medicine images is usually reduced by the analysis of imaging data in a fourier transform environment. the main drawback of this environment belongs to low signal to noise ratio in high frequencies because removing noise frequencies may remove data and times...

اخلاص, هانیه , منصوری, نبی الله , منظم, محمدرضا , نصیری, پروین ,

Introduction: Noise is one of hazardous agents of workplaces in industries. Electric industries and power plants are among industries in which noise pollution should be taken into account. This study aimed to develop and verify a statistical model for acoustic wave propagation in an indoor environment for noise related risk reduction management. . Material and Method: This theoretical-experime...

Journal: :jundishapur journal of health sciences 0
farhad forouharmajd department of occupational health engineering, school of public health, isfahan university of medical sciences, isfahan, ir iran mitra shabab department of occupational health engineering, school of public health, isfahan university of medical sciences, isfahan, ir iran; department of occupational health engineering, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran; occupational health engineering department, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran. tel: +98-6133738269, fax: +98-33738282

conclusions according to the factory noise map, except for the control rooms with 81 dba noise, other cases of measuring stations were higher than the standard exposure of 85 dba noise. as a result, the implementation of control strategies, such as inspection and performance of control systems and insulation of the control room to prevent unnecessary exposure noise, are necessary. background st...

ژورنال: دانشور پزشکی 2008
اکبری, مهدی , خوانین, دکتر علی , فتح‌الهی, دکتر یعقوب , مرتضوی, دکتر سیدباقر , میرزایی, دکتر رمضان , کاظم‌نژاد, دکتر انوشیروان ,

  Introduction: In the present study, was performed to investigate the relationship between toluene(1000 ppm), noise, toluene and toluene along with noise (frequencies 250- 2000 Hz) per auditory Brain Stem response (ABR) on rabbits in which being exposed to this contaminants.   Materials & Methods: Three months old, male adult white New Zealand rabbits (1400-1700 g body weight) were used throug...

ژورنال: سلامت و محیط زیست 2012
اعظم, کمال, حسینی گوشه, سید نورالدین, فرهنگ دهقان, سمیه, منظم, محمدرضا, نصیری, پروین,

Background and Objectives: Sound of motorcycles plays an important role in noise pollution in big cities. This is due to the lack of national law or standards to control the noise of domestic and also imported motorcycles. This study tries to introduce a practical limit value in different stage of motorcycle life cycle by assessing their noise pollution. Materials and Methods: First the motorcy...

Mashallah Aghilinejad, Masoumeh Ghiasvand, Seyed Javad Haji-Miresmaeil,

  Abstract   Background: Previous studies have indicated an unspecific correlation between noise   exposure and blood pressure disturbances. Blood pressure disturbances could be caused   by the environmental hazards such as noise exposure. The aim of this study is to analyze   whether there is a relationship between noise exposure and hypertension.   Methods: Atotal sample of 218 workers workin...

Journal: :مجله دانشگاه علوم پزشکی کرمانشاه 0
shahram vosoughi hassan asilian mahabadi ali khavanin mojdeh salehnia abdolhossein shahverdi vahid esmaeili

background: formaldehyde (h2c = o), is a member of aldehyde family with a simplest organic molecule, used in various industries. the aim of this experimental study was to investigate the effects of simultaneous formaldehyde and noise exposure on hormonal pituitary-gonadal axis in adult male mice. methods: 46 adult male mice were randomly assigned to one control group and three experimental grou...

ژورنال: سلامت کار ایران 2017

Background and aims: Noise is one of the harmful parameters of the industrial environments. It affects the human health in different aspects including harmful effects on hearing damage, vision, neurological and psychiatric, hormones, physiological and mental systems. Paying attention to the importance of hormonal effects on human body, the aim of the present study is to investigate the effects ...

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