نتایج جستجو برای: equivalent sound level

تعداد نتایج: 1290264  

Journal: :جنگل و فرآورده های چوب 0
معصومه احمدی دانشجوی کارشناسی ‏ارشد مهندسی جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران مقداد جورغلامی دانشیار گروه جنگلداری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران باریس مجنونیان استاد گروه جنگلداری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران رسول یاراحمدی استادیار دانشکدة بهداشت دانشگاه علوم پزشکی و خدمات درمانی ایران، تهران، ایران

chainsaw is an important machine for tree felling limbing and bucking in hyrcanian forest and the major problems related to using forest machines was sound intensity. the aim of this study was to measure the sound level in occupational exposure of workers, determine the exposure time of workers and comparison of the variables among the workers. this study was carried out in namkhaneh district i...

Journal: :jundishapur journal of health sciences 0
behzad fouladi dehaghi department of occupational health, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran; department of occupational health, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran. tel/fax: +98-6133735318 leila ibrahimi ghavam abadi department of environmental management, ahvaz branch, islamic azad university, ahvaz, ir iran hamid rasi department of occupational health, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran kambiz ahmadi angali department of occupational health, school of health, ahvaz jundishapur university of medical sciences, ahvaz, ir iran

results according to the study results, noise levels in a co2 plant’s house and control room ranged from 88 to 102 db and 79 to 82 db (a), respectively. in order to reduce the amount of emitted noise in the co2 plant house and control room, a noise control plan was implemented in each part of the facility; it was met with effective results. conclusions the findings of this investigation have cl...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه ولی عصر (عج) - رفسنجان - دانشکده ادبیات و علوم انسانی 1393

the present study investigated construct equivalence of multiple choice (mc) and constructed response (cr) item types across stem and content equivalent mc and cr items (item type ‘a’), non-stem-equivalent but content equivalent mc and cr items (item type ‘b’), and non-stem and non-content equivalent mc and cr items (item type ‘c’). one hundred seventy english-major undergraduates completed mc ...

A. MALEKI M. LASHGARI

ABSTRACT- Noise is considered as one of the most debilitating conditions in farming operations. In this study, a number of factors affecting the noise generated by Sampo 3065 combine harvesters were evaluated. Factors were engine speed and gear ratio for combines with and without original cabins. A factorial experiment arranged as a completely randomized design with four replicates was used. Re...

Journal: :international journal of occupational hygiene 0
milad derakhshan jazari msc of occupational health engineering, tehran university of medical sciences, tehran, iran mahdyeh boubehrejh national center of air and climate change, department of the environment, tehran, iran maryam avishan national center of air and climate change, department of the environment, tehran, iran jamshid gholampour [email protected] mohammad reza monazzam esmail pour professor of occupational health engineering, tehran university of medical sciences, tehran, iran mohsen meshkani [email protected]

original article   introduction: wind-turbine noise emission and its environmental impact are considerable issues nowadays. considering the importance of the issue, the purpose of this study was to prepare noise map and wind turbines sound characteristics on the largest wind farm of iran. method: this study was carried out in two phases:1) in order to prepare the daytime sound level (ld) noise ...

ژورنال: سلامت کار ایران 2018

Abstract: Background and aims: Using water pump in residential buildings to provide the required water pressure is accompanied by noise pollution and the annoyance of residents. So, the purpose of this study is to reduce water pump noise pollution with designed acoustic curtains in a residential building of Qazvin city.   Methods: The mean sound pressure level was measured before and ...

Journal: :Civil Aviation High Technologies 2020

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تبریز 1382

‏‎despite the different criticisms on contrastive analysis it has been proved that the results of it(when processed) can be useful in a tefl environment, specially at the level of phonology.this study is an attempt to compare and contrast the sound systems of kurdish and english for pedagogical aims.the consonants,vowels,stress and intonation of the two languages are described by the same model...

It is accepted that noise pollution has a major impact on health, such as physical, physiological, psychological and performance related effects, all over the world. This study aims to evaluate noise pollution in four urban parks located in Sanandaj City, Iran and to zone it in GIS environment. Sound pressure level (SPL) and maximum sound level (Lmax) were measured at 45 points (each point was ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید