Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 2 de 2
Add filters

Document Type
Year range
PLoS One ; 16(7): e0255051, 2021.
Article in English | MEDLINE | ID: covidwho-1327979


At present, people are demanding better indoor air quality during the COVID-19 pandemic. In addition to maintaining the basic functions, new air-conditioning should also add air purification functions to improve indoor air quality and reduce the possibility of virus transmission. Nowadays, there is lack of research results on the innovation of air-conditioning. The aim of this study is to present a two-stage mathematical model for identifying critical manufacturing factors in the innovation process of air conditioning. In this paper, Kano and quality function deployment (QFD) are used to analyze the critical factors affecting air-conditioning innovation. Some studies have proposed using Kano-QFD model to analyze product innovation, but the study only studies one stage, which loses the analysis of the subsequent stages of product innovation. Based on this, this paper studies the priority method of two-stage critical factors for air-conditioning innovation. Firstly, the questionnaire survey and fuzzy sets are used to collect demand information of multi-agent (customers and professional technicians). Secondly, the Kano model is used to classify and calculate satisfaction of multi-agent. Then, QFD is used to transform multi-agent demands into engineering property indexes (first stage) and technical property indexes (second stage) and calculate the weight of each index. Finally, the applicability and superiority of this method is illustrated by taking the central air-conditioning as an example.

Air Conditioning , Air Microbiology , COVID-19/epidemiology , Filtration/instrumentation , Models, Theoretical , Pandemics , COVID-19/prevention & control , COVID-19/transmission , Fuzzy Logic
Ann Transl Med ; 9(2): 100, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-1079877


BACKGROUND: To investigate the temporal pattern of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presence on ocular surfaces using conjunctival swabs in coronavirus disease 2019 (COVID-19) patients. METHODS: This study included 59 patients (32 newly admitted and 27 hospitalized for ≥2 weeks) with a COVID-19-confirmed diagnosis at the Shanghai Public Health Clinical Center from March 3, 2020, to March 21, 2020. Conjunctival swab samples were collected from both eyes of all the 59 patients and were tested by reverse transcription polymerase chain reaction (RT-PCR) assay. The range of sampling time lies widely between 1 and 50 days since symptom onset. RESULTS: Among the 32 newly admitted patients, positive RT-PCR results for SARS-CoV-2 in conjunctival swab samples were reported in 2 patients (one eye for each) without ocular discomfort, but 1 positive case had conjunctival congestion. The positive results were detected on Day 5 for 1 patient and Day 7 for the other, but repeated tests after 1 week were negative for both patients. All 27 patients who had been hospitalized for ≥2 weeks had negative test results. The mean time from symptom onset to sampling of 2 positive cases was significantly less than that of 57 negative cases (P<0.001). CONCLUSIONS: SARS-CoV-2 on the ocular surface can be detected in the early phase of COVID-19. The risk of ocular transmission remains and might be higher in the early phase.