Inclusion Criteria:  For COPD patients:  Patients able and willing to sign an informed consent to participate in the study; Patient is aged 40 years or older with a smoking history of ≥10 pack years; Patients with COPD confirmed previously by a detailed medical history and examination; Patients presenting with moderate or severe exacerbation of chronic obstructive pulmonary disease. Patient is treated by a monotherapy long-acting muscarinic antagonist (LAMA), or LAMA plus long acting beta2-agonist (LABA), or inhaled corticosteroid (ICS) plus LABA, or LAMA plus LABA plus ICS.  For asthma patients:  Patients able and willing to sign an informed consent to participate in the study; Patient is aged 3 years or older; Patients with asthma confirmed previously by a detailed medical history and examination; Patients presenting with moderate or severe exacerbation of asthma; Patient is treated by a monotherapy ICS or ICS plus LABA or other controllers.  Exclusion Criteria:  Age up to 3 years for asthma patients and up to 40 years for COPD patients; Patient refusal to participate in the study; Patients with subcutaneous emphysema, with damaged skin on the surface of the chest, with drainage in the pleural space, patients undergoing mechanical ventilation; Patients with asthma-COPD overlap or presence of other known chronic lung conditions such tuberculosis, cystic fibrosis or clinically significant bronchiectasis; Mental illness, other known acute diseases or known chronic decompensated diseases, such as a known active malignancy or severe heart failure, other known ongoing infection.