this study was conducted to rank the broiler farms based on buildings, installations and equipment and its effect on production factors. to determine the contribution of each factor in ranking of farms, a multi-criteriadecision analysis (saw) was used. data of 108 broilers were recorded in specific forms and the amount of investment per broiler was calculated for individual factors. to calculat...

introduction: tuberculosis (tb), with different types of respiratory tract involvements, has a high rate of mortality all around the world. endobronchial involvement, which is a slightly common tuberculous infection, requires special attention due to its severe complications such as bronchostenosis. aim of study of this study was describes, one type of pulmonary tuberculosis with less diagnosed...

Fires caused by cables occur frequently in mines, which endanger the safety of workers. To explore characteristics a multilayer cable fire mine tunnel, simulations were carried out using Fire Dynamics Simulator (FDS). The influence tray spacing, ignition position, and tunnel ventilation speed on studied. results showed that these factors change amount contact between air, heat accumulation, tra...

Tunnel widely exists in highway, subway and other underground buildings. Due to the structural limitations, direction of evacuation is consistent with main flow smoke tunnel. For design exhaust system, traditional methods aim at reducing overall concentration whole However, when fire hazard occurs, rapid personnel escape requires higher visibility. In this paper, a novel air supply device desig...

In recent years, inclined shafts have been widely used in long mountain tunnels, but the corresponding design and construction technical specifications need to be improved. By means of literature statistics actual cases, a comprehensive systematic review is made on tunnel profile, lining structure, operation ventilation, methods, machinery for tunnels. The results show that: (1) gentle slope se...

Greenhouse technology has advanced over the past few decades in terms of environmental control (e.g., indoor temperature, relative humidity, and CO2 concentration). Ventilation is an effective way to adjust climate. Natural ventilation gained significant research attention recently because its low energy requirement. To evaluate effectiveness, rate often used. This review summarizes published p...

This paper studies the effect of natural ventilation on spread COVID-19 virus from a patient room to an adjacent with help airflow. The importance this study is since contamination can easily transfer airflow one next or corridor. aims determine spaces patients’ room.For evaluation, we have used mechanical modelling and CFD simulation evaluate transmission contaminated space clean space. During...