نتایج جستجو برای: equivalent sound level
تعداد نتایج: 1290264 فیلتر نتایج به سال:
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...
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...
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 ...
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...
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 ...
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 ...
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