The purpose of this study was to determine the effects of vowel height and vocal intensity on the magnitude of anticipatory nasal airflow in normal speakers when producing vowel-nasal-vowel (VNV) sequences. Measurements of nasal and oral airflow were obtained from 15 men and 12 women with normal speech during production of the VNV sequences /ini/ and /ana/ at low, medium, and high intensity lev...

Kitchen is an important place in Chinese residential building. However, unfavourable thermal environment and unsatisfied air quality occur during cooking. Studies on kitchen are experimentally investigated with enough make-up airflow. But mostly normal kitchens merely installed a exhaust hood have not supply system. This work carried out numerical simulation to investigate indoor under natural ...

Information on the size and shape of about 8500 maximum expiratory flow-volume (MEFV) curves was related multivariately to respiratory symptoms to construct a sensitive measure of airflow limitation. The data were obtained in an epidemiological follow-up study of a normal population in The Netherlands. Using non-linear canonical correlation analysis, thirteen variables from each curve yielded t...

PURPOSE To study the relationship between sleep position and ocular surface symptoms and signs in an high air flow environment. METHODS Prospective observational study of new patients attending the dry eye clinic was performed. Patients with pre-existing ocular history, relevant systemic history (e.g. Sjogren's syndrome) or who were using topical or systemic therapy for dry eye were not inclu...

Centrifugal compressors produce high pressure ratio and rotate at speeds. So, a tiny unbalance can produce severe vibration. In this paper, effects of impeller gap on rotor vibration in a high speed centrifugal compressor is investigated. For this purpose, a numerical and experimental analysis are carried out. The moving reference frame method in FLUENT software is used for modeling of geometri...

In the post epidemic era, movement and distribution of pathogenic airflow droplets produced by cough in building space have been widely studied. Due to limitations research methods, there are few detailed data on temporal spatial boundary conditions during cough, which is basis key computer simulation. Previous experiments obtained velocity away from mouth. This study aims infer at mouth for CF...

BACKGROUND The Global Initiative for Chronic Obstructive Lung Disease (GOLD) report provides a framework for classifying COPD reflecting the impacts of disease on patients and for targeting treatment recommendations. The GOLD 2017 introduced a new classification with 16 subgroups based on a composite of spirometry and symptoms/exacerbations. METHODS Data from the population-based PLATINO stud...

Dry powder inhalers (DPIs) are widely and increasingly used in clinical practice because they represent a substantial advancement in inhalation technology. The effectiveness of a powdered drug to inhale depends on the inspiratory flow rate generated by the patient and on the turbulence produced by the intrinsic resistance of the DPI. While the inspiratory flow is variable with the patient's abi...

The flow dynamics of respiratory airflow is the basic factor that influences the ventilation function of the upper airway. This research aimed to investigate the pharyngeal flow field characteristics after Twin Block (TB) treatment in growing patients with Class II(1) and mandibular retrognathia by computation fluid dynamics (CFD) simulation. Cone beam computed tomography (CBCT) scans of patien...

Tide-induced hydraulic head fluctuation results in significant airflow above the water table if the aquifer is air-confined, for example, if the aquifer is capped by low permeability materials. Hypothetical studies on the interaction between tidal fluctuation and airflow in coastal aquifers are carried out using an air–water two-phase numerical model. The results show that both the amplitude of...