This paper describes the fluid mechanics of natural ventilation by the combined effects of buoyancy and wind. Attention is restricted to transient draining flows in a space containing buoyant fluid, when the wind and buoyancy forces reinforce one another. The flows have been studied theoretically and the results compared with small-scale laboratory experiments. Connections between the enclosure...

RATIONALE Mechanical ventilation is known to induce ventilator-induced diaphragm dysfunction. Patients submitted to mechanical ventilation often receive massive doses of corticosteroids that may cause further deterioration of diaphragm function. OBJECTIVES To examine whether the combination of 24 hours of controlled mechanical ventilation with corticosteroid administration would exacerbate ve...

label switching technology is a flexible and high performance method for forwarding layer three packets that are mapped to layer two flows. each label switch router, lsr, needs a specific label for every flow, where the number of labels depends on the mapping and granularity of flows. data and control driven methods are the most significant and popular methods in label mapping policy. the above...

The impacts of ventilation ratio and vent balance on cooling load and air flow of naturally ventilated attics are studied in this paper using an unsteady computational fluid dynamics (CFD) model. Buoyancy-driven turbulent ventilations in attics of gable-roof residential buildings are simulated for typical summer conditions. Ventilation ratios from 1/400 to 1/25 combined with both balanced and u...

Traffic–related pollutant has been recognized as an air pollution hot spot due to its large emission rate and great health impacts for the exposed population. In the present investigation, a computational fluid dynamics technique is used to evaluate the effect of traffic pollutions on indoor air quality of a naturally ventilated building. The transport of street-level nonreactive pollutants emi...

BACKGROUND: The aim of this study was to test the hypothesis that a new mode of ventilation (pressure-regulated volume control; PRVC) is associated with improvements in respiratory mechanics and outcome when compared with conventional volume control (VC) ventilation in patients with acute respiratory failure. We conducted a randomised, prospective, open, cross over trial on 44 patients with acu...

This study was conducted to determine the significance of computational results according application porous media in occupied zone when analyzing air temperature distribution broiler house using fluid dynamics. For such experimental conditions, outside controlled two circumstances : 1) summer and 2) winter. Also, ventilation methods were as well tunnel cross ventilation, differentiating amount...

Explicit algebraic equations for calculation of wind and stack driven ventilation were developed by parametrically matching exact solutions to the flow equations for building envelopes. These separate wind and stack effect flow calculation procedures were incorporated in a simple natural ventilation model, AIM-2, with empirical functions for superposition of wind and stack effect and for estima...

BACKGROUND No guidelines exist on assessing ventilation through air changes per hour (ACH) using a vaneometer. The objective of the study was to evaluate the position and frequency for measuring air velocity using a vaneometer to assess ventilation with ACH; and to assess influence of ambient temperature and weather on ACH. METHODS Cross-sectional survey in six urban health facilities in Kamp...

The aim of this article was to review the role of noninvasive ventilation (NIV) in acute pulmonary infectious diseases, such as severe acute respiratory syndrome (SARS), H1N1 and tuberculosis, and to assess the risk of disease transmission with the use of NIV from patients to healthcare workers. We performed a clinical review by searching Medline and EMBASE. These databases were searched for ar...