نتایج جستجو برای: sound pressure load
تعداد نتایج: 643260 فیلتر نتایج به سال:
Background: The higher dietary acid load may affect blood pressure, blood sugar levels, and insulin levels. The purpose of this systematic review study is to examine the relation of dietary acid load with blood pressure and blood glucose. Methods: We searched in PubMed, Google Scholar, Scopus and Medline up to July 2016, using the keywords "dietary acid load", "serum glucose&quo...
Background and Objectives: Noise pollution is one of the most harmful physical factors in working environments in developed and developing countries, which has significant impacts on the workers’ quality of life. The aim of this study was to investigate mental and physiological effects of chronic exposure to noise. Methods: This is a cross-sectional study carried out randomly in 2018 on 250 wo...
The widespread use of squirrel cage fans, especially in ventilation and home and industrial environments, has led to the formation of many research efforts to improve performance and reduce the sound produced by this type of fan. In the literature, the most important factor in generating sound in this category of fans is the confrontation between the rotor exit flow and the volute of the fan. I...
Background: Today, the effects of environmental pollution on human life and human needs, which reduces the level of community health caused by traffic noise in large cities, are clearly visible by creating irritation and pathogenic conditions. The aim of this study was to assess the risk of noise pollution resulted from central traffic in Shiraz by analyzing its indicators and related componen...
the aim of the present study was to examine the rate of noise induced hearing loss in a group of punching and cutting section and other occupational groups workers and its relation with sound pressure levels, age and work history. this descriptive, cross-sectional study included 245 workers of the punching and cutting section and other occupational groups of an iranian axial parts factory in 20...
workplace factors such as sound must have the minimum impact on the operators of combine harvester, so that they can guide and control many functions of the combine. in this study, some factors affecting the noise generated by two combine harvesters john deere 1055 and sampo 3065 were evaluated. research factors were engine speed, gear ratios, type of operation and microphone distance. the resu...
We investigated the issue of noise pollution in the Bidboland gas refineryby noise measurement and surveys. The Bidboland gas refinery has several process units.The sound pressure levels were measured at several places, such as units of 200, 300,400, 500, boiler, powerhouse area, cooling towers pumps, and maintenance area, and thecorresponding noise maps were produced by using sound plan softwa...
On the basis of the traditional structure of noise barrier, this paper seeks aerodynamic load to reduce the variation of maximum surface configuration (porous structure). Using the numerical simulation method, this paper builds a three-dimensional numerical model of deloading type noise barriers and trains. The large fluid calculation software, Fluent, is adopted to conduct simulation calculati...
Background & Aims of the Study: Among the environmental pollutions, noise pollution, due to the potential physiological and psychological effects on humans, is of a particular importance. Exposure to noise can result in hearing loss in citizens. Health risks from noise associated with road traffic. Noise health effects are the health consequences of elevated sound levels. This ...
The sound properties of modern cars play an increasingly important role on the overall impression of a vehicle. One of the major sound sources is hereby the exhaust system, which is exposed to large pressure pulsations resulting from the periodically blown out exhaust gas of the car engine. These large pressure pulsations lead to vibrations of the thin walls of the exhaust system and thus creat...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید