Seite - 320 - in Intelligent Environments 2019 - Workshop Proceedings of the 15th International Conference on Intelligent Environments

COPLEY),aCriticalFlowController (COPLEYTPK)andacollection tube (DUSAfor DPI,COPLEY) [24]. Figure2. DUSAsetup forDPI test. First, amassflowmeter (TSI Incorporated) [25]was attached to the assemblageby a mouthpiece adaptor. The air flow was then adjusted to the test flow rate (15 to 90 L/min with a step size of 5 L/min). Afterwards, the flowmeter was replaced with the inhalerattachedtotheadd-onacousticdevice.ThesoundswererecordedusinganiPhone 6 microphone placed at a distance of approximately 1 meter away from the acoustic device.The recording timeswerebetween12 to15secondswhich is equivalent to three inhalations for each recordedsignal.These signalswere storedaswavefiles. 2.2. SignalProcessingandsegmentation Figure3. Inhalation recordingswitha testflowrateof20L/min Z.Jeddi etal. /Estimationof InhalationFlowParameters forAsthmaMonitoring320