scholarly journals HVAC systems for environmental control to minimize the COVID-19 infection

2020 ◽  
Vol 29 (9) ◽  
pp. 1195-1201
Author(s):  
Junwei Ding ◽  
Chuck Wah Yu ◽  
Shi-Jie Cao
Keyword(s):  
Thermal Comfort ◽  
Disease Transmission ◽  
Environmental Control ◽  
Ventilation System ◽  
Virus Transmission ◽  
Hvac Systems ◽  
Health Care Facilities ◽  
Indoor Environments ◽  
Healthy Environment ◽  
And Control

The outbreak of pneumonia caused by 2019 Novel Coronavirus arises significant concern for virus transmission and control. The control of the indoor environment or public-enclosed environment is crucial to reduce the risk of infection. Heating, ventilation, air-conditioning (HVAC) systems are used to create a healthy, thermal-comfort indoor environments. Thus, the rational use of HVAC systems is of great importance for the environmental control to reduce infection risk and to improve human wellbeing in the pandemic. In order to satisfy the requirement of better healthy environment and more thermal comfort performance of indoor ventilation system, prevention of indoor pollution is essential, especially considering the purpose of disease transmission resistance. This paper investigated the collective contagion events in enclosed spaces as well as engineering control against virus spread with ventilation systems for health-care facilities and public vehicles. Future challenges of HVAC design and control were discussed.

scholarly journals Novel Integrated and Optimal Control of Indoor Environmental Devices for Thermal Comfort Using Double Deep Q-Network

Atmosphere ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 629
Author(s):  
Sun-Ho Kim ◽  
Young-Ran Yoon ◽  
Jeong-Won Kim ◽  
Hyeun-Jun Moon
Keyword(s):  
Optimal Control ◽  
Energy Consumption ◽  
Thermal Comfort ◽  
Control Method ◽  
Environmental Control ◽  
Ventilation System ◽  
Low Energy ◽  
Good Ability ◽  
Low Energy Consumption ◽  
Control Devices

Maintaining a pleasant indoor environment with low energy consumption is important for healthy and comfortable living in buildings. In previous studies, we proposed the integrated comfort control (ICC) algorithm, which integrates several indoor environmental control devices, including an air conditioner, a ventilation system, and a humidifier. The ICC algorithm is operated by simple on/off control to maintain indoor temperature and relative humidity within a defined comfort range. This simple control method can cause inefficient building operation because it does not reflect the changes in indoor–outdoor environmental conditions and the status of the control devices. To overcome this limitation, we suggest the artificial intelligence integrated comfort control (AI2CC) algorithm using a double deep Q-network(DDQN), which uses a data-driven approach to find the optimal control of several environmental control devices to maintain thermal comfort with low energy consumption. The suggested AI2CC showed a good ability to learn how to operate devices optimally to improve indoor thermal comfort while reducing energy consumption. Compared to the previous approach (ICC), the AI2CC reduced energy consumption by 14.8%, increased the comfort ratio by 6.4%, and decreased the time to reach the comfort zone by 54.1 min.

scholarly journals Transmission Potential and Severity of COVID-19 in Pakistan

2020 ◽  
Author(s):  
Sohail Raza ◽  
Muhammad Asif Rasheed ◽  
Muhammad Khalid Rashid
Keyword(s):  
Health Care ◽  
Disease Transmission ◽  
Virus Transmission ◽  
Case Fatality ◽  
Health Care Facilities ◽  
Jammu And Kashmir ◽  
Epidemiological Analysis ◽  
Transmission Potential ◽  
Control Disease ◽  
Gilgit Baltistan

As of 26 March 2020, Pakistan had 1179 cases of COVID-19, with most 421 cases from Sindh, 394 cases, 131 cases, 123 cases, 84 cases, 25 cases and 01 cases from Punjab, Balochistan, Khyber Pakhtunkhwa, Gilgit-Baltistan, Islamabad Capital Territory, and Azad Jammu and Kashmir respectively. Travel-related cases were the main source of SARS-CoV-2 infection during the early phase of the pandemic in Pakistan. Nevertheless, cases of local virus transmission are increasing day by day. As of 26 March 2020, nine deaths have been reported from COVID-19. The case fatality rate is 0.8%, which is less compare to China, Italy, USA, and Iran. The SIR (Susceptible-Infected-Recovered) model of epidemiological analysis predicts that almost 90 million population will be infected in the coming days with 5% critical cases that need health care facilities. However, the Pakistan health care system cannot provide services to this much population. Hence, we need to act timely to reduce this number by restricting local transmission of the disease. This can be done by mass testing, quarantine, isolation and social distancing of the active coronavirus cases in Pakistan. Moreover, better communication between the authorities is very much required to control disease transmission.

scholarly journals Ventilation System Operation to Minimize the COVID-19 Airborne Transmission in Schools

2021 ◽  
Vol 65 (2-4) ◽  
pp. 300-306
Author(s):  
Luca Stabile ◽  
Antonio Pacitto ◽  
Giorgio Buonanno ◽  
Marco Dell’Isola
Keyword(s):  
Exchange Rates ◽  
Ventilation System ◽  
Virus Transmission ◽  
Infection Risk ◽  
Indoor Environments ◽  
Mass Balance Equation ◽  
System Operation ◽  
Airborne Transmission ◽  
Mechanically Ventilated ◽  
Route Of Transmission

Minimizing the SARS-CoV-2 virus transmission is essential to face the COVID-19 pandemic. This is even more important for highly crowded indoor environments, e.g. schools, where the mitigation solutions based on social distancing and hand washing seem to be not effective to reduce the virus airborne transmission mode, which is the main route of transmission. To minimize the airborne virus transmission a proper ventilation is necessary. In the study, a simplified mass balance equation (box-model) was applied to school scenarios in order to determine the required conditions to maintain the infection risk below an acceptable level. In particular, the required air exchange rates for mechanically-ventilated classrooms and the adequate airing procedures for naturally ventilated classrooms were determined. Moreover, for naturally ventilated classrooms, a control strategy based on the measurement of CO2 indoor concentration was also developed.

scholarly journals Impact of elevated air velocity on subjective thermal comfort sensation under asymmetric radiation and variable airflow direction

2017 ◽  
Vol 42 (2) ◽  
pp. 173-193 ◽  
Author(s):  
Ferenc Kalmár
Keyword(s):  
Thermal Comfort ◽  
Skin Temperature ◽  
Environmental Conditions ◽  
Ventilation System ◽  
Indoor Environments ◽  
Facial Skin ◽  
Air Velocity ◽  
Men And Women ◽  
Significant Difference ◽  
Skin Temperatures

Buildings rarely have homogeneous thermal indoor environments. Transparent building elements are one of the sources of thermal asymmetry. Using advanced personalised ventilation systems, the discomfort caused by radiation asymmetry may be reduced. A series of measurements involving 20 subjects were carried out under controlled environmental conditions to investigate subjective thermal comfort in the case of asymmetric radiation combined with the personalised ventilation. Analysis showed that the subjective thermal comfort sensation without a personalised ventilation system is similar to the calculated predicted mean vote. However, there is a significant difference between the responses of female and male participants. The advanced personalised ventilation system lowers the subjective thermal comfort sensation, but does it differently for men and women. The skin temperatures of the hands of the women were significantly lower than that of the men. In the case of the men, radiation asymmetry led to significant differences in the facial skin temperature, while in the case of the women, the differences in the facial skin temperature were not significant.

THE 2019 NOVEL PANDEMIC OF CORONAVIRUS DISEASE (COVID-19): A STUDY OF EXISTING EVIDENCE IN THE INDIAN POPULATION

2020 ◽  
Vol 7 (2) ◽  
pp. 199-204
Author(s):  
Shrikant Verma ◽  
Mohammad Abbas ◽  
Sushma Verma ◽  
Syed Tasleem Raza ◽  
Farzana Mahdi
Keyword(s):  
Disease Transmission ◽  
Indian Population ◽  
Respiratory Infections ◽  
Clinical Signs ◽  
Case Fatality ◽  
Public Health Emergency ◽  
The World ◽  
And Control ◽  
General Wellbeing ◽  
Different Parts

A novel spillover coronavirus (nCoV), with its epicenter in Wuhan, China's People's Republic, has emerged as an international public health emergency. This began as an outbreak in December 2019, and till November eighth, 2020, there have been 8.5 million affirmed instances of novel Covid disease2019 (COVID-19) in India, with 1,26,611 deaths, resulting in an overall case fatality rate of 1.48 percent. Coronavirus clinical signs are fundamentally the same as those of other respiratory infections. In different parts of the world, the quantity of research center affirmed cases and related passings are rising consistently. The COVID- 19 is an arising pandemic-responsible viral infection. Coronavirus has influenced huge parts of the total populace, which has prompted a global general wellbeing crisis, setting all health associations on high attentive. This review sums up the overall landmass, virology, pathogenesis, the study of disease transmission, clinical introduction, determination, treatment, and control of COVID-19 with the reference to India.

Green peach aphid and potato leafroll virus: transmission and control

2020 ◽  
Author(s):  
R.A. Bagrov ◽  
◽  
V.I. Leunov
Keyword(s):  
Myzus Persicae ◽  
Green Peach Aphid ◽  
Virus Transmission ◽  
Potato Leafroll Virus ◽  
Factors Affecting ◽  
Potato Viruses ◽  
Tuber Necrosis ◽  
Aphid Vectors ◽  
Leafroll Virus ◽  
And Control

The mechanisms of transmission of potato viruses from plants to aphid vectors and from aphids to uninfected plants are described, including the example of the green peach aphid (Myzus persicae, GPA). Factors affecting the spreading of tuber necrosis and its manifestation on plants infected with potato leafroll virus (PLRV) are discussed. Recommendations for PLRV and GPA control in the field are given.

Communicable and Other Infectious Diseases

2020 ◽  
Author(s):  
Markus Frischhut
Keyword(s):  
Public Health ◽  
European Union ◽  
Infectious Diseases ◽  
Disease Transmission ◽  
Eu Law ◽  
The European Union ◽  
Ethical Perspective ◽  
Health Measures ◽  
Environment Agency ◽  
And Control

This chapter discusses the most important features of EU law on infectious diseases. Communicable diseases not only cross borders, they also often require measures that cross different areas of policy because of different vectors for disease transmission. The relevant EU law cannot be attributed to one sectoral policy only, and thus various EU agencies participate in protecting public health. The key agency is the European Centre for Disease Prevention and Control. Other important agencies include the European Environment Agency; European Food Safety Authority; and the Consumers, Health, Agriculture and Food Executive Agency. However, while integration at the EU level has facilitated protection of the public's health, it also has created potential conflicts among the different objectives of the European Union. The internal market promotes the free movement of products, but public health measures can require restrictions of trade. Other conflicts can arise if protective public health measures conflict with individual human rights. The chapter then considers risk assessment and the different tools of risk management used in dealing with the challenges of infectious diseases. It also turns to the external and ethical perspective and the role the European Union takes in global health.

scholarly journals Barriers on Establishing Passive Strategies in Office Spaces: A Case Study in a Historic University Building

2021 ◽  
Vol 13 (8) ◽  
pp. 4563
Author(s):  
Nuno Baía Baía Saraiva ◽  
Luisa Dias Dias Pereira ◽  
Adélio Rodrigues Gaspar ◽  
José Joaquim da Costa
Keyword(s):  
Thermal Comfort ◽  
Indoor Environment ◽  
Hvac Systems ◽  
Heritage Buildings ◽  
Full Capacity ◽  
Free Cooling ◽  
Passive Strategies ◽  
The University ◽  
Indoor Conditions

The adaptation of spaces to different usage typologies can be complex in heritage buildings. Facilities were initially planned for a specific type of use that, when changed, require additional measures to ensure a suitable indoor environment. Passive strategies—e.g., free cooling—are commonly used as an alternative without requiring equipment installation. However, its implementation often leads to unsatisfactory conditions. Therefore, it is important to clarify the main barriers to achieving thermal comfort in readapted historic buildings. The present work investigates the thermal comfort conditions reported by workers in office spaces of a historic building in the University of Coimbra. A monitoring campaign was carried out between May and September 2020 to assess indoor conditions’ quality. Due to the current pandemic of COVID-19, offices were not occupied at full capacity. A one-day evaluation of thermal comfort was made using a climate analyzer and six occupants were surveyed on 19 August 2020. The main results highlighted discomfort due to overheating of spaces. The causes were related to the combination of inadequate implementation of the free cooling actions and the building use. Furthermore, it was recommended the installation of HVAC systems in case of full capacity.

scholarly journals An Investigation of the General Population’s Self-Reported Hand Hygiene Behaviour and Compliance in a Cross-European Setting

2021 ◽  
Vol 18 (5) ◽  
pp. 2402
Author(s):  
Aaron Lawson ◽  
Marie Vaganay-Miller ◽  
Robert Cameron
Keyword(s):  
General Population ◽  
Hand Hygiene ◽  
Disease Transmission ◽  
Communicable Disease ◽  
Hygiene Practice ◽  
Hygiene Behaviour ◽  
Level Of Understanding ◽  
The Uk ◽  
Travel Abroad ◽  
And Control

Every year, thousands of people from the UK travel to other countries for work and leisure. Europe, and particularly Spain, is one of the most popular travel destinations for people from the UK. However, it is known that travel to other countries can enhance the risk of communicable disease transmission from person to person, especially when a new one emerges. Adequate hand hygiene behaviour and compliance is widely accepted as being a simple, effective method in preventing the spread of communicable diseases that may be contracted during travel abroad. There is a well-established body of work investigating hand hygiene practice and compliance in community settings, but no recent studies have examined the hand hygiene practice and compliance of the general population when travelling abroad or in a cross-European context. The findings of this study indicated that most UK members of the general population when travelling abroad have a good level of understanding of the importance of adequate hand hygiene practice and compliance and its role regarding communicable disease prevention and control. As such, self-reported levels of compliance were high. Similar findings were made for Spanish members of the general population. However, while self-reported perceptions of adequacy of hand hygiene performance were relatively high, particularly among UK respondents, this was not supported by responses specifically focused on hand hygiene behaviour. However, differences in self-reported adequacy regarding the importance of handwashing versus hand drying, the number of steps that should be followed and the length of time that should be spent washing and drying hands were found for each group. This suggests that self-reported compliance may reflect intention to practice hand hygiene rather than true compliance. It also suggests that there are gaps in knowledge regarding the adequate method of hand hygiene among the cohort as a whole, and indeed these differences may account be a factor in for the high transmission rates of communicable disease when travelling abroad.

scholarly journals A Multi-Timescale Bilinear Model for Optimization and Control of HVAC Systems with Consistency

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 400 ◽  
Author(s):  
Zelin Nie ◽  
Feng Gao ◽  
Chao-Bo Yan
Keyword(s):  
Optimization Model ◽  
Air Conditioning ◽  
State Of The Art ◽  
Hvac Systems ◽  
Practical Significance ◽  
Hvac System ◽  
Bilinear Model ◽  
Optimization And Control ◽  
And Control ◽  
Slow Timescale

Reducing the energy consumption of the heating, ventilation, and air conditioning (HVAC) systems while ensuring users’ comfort is of both academic and practical significance. However, the-state-of-the-art of the optimization model of the HVAC system is that either the thermal dynamic model is simplified as a linear model, or the optimization model of the HVAC system is single-timescale, which leads to heavy computation burden. To balance the practicality and the overhead of computation, in this paper, a multi-timescale bilinear model of HVAC systems is proposed. To guarantee the consistency of models in different timescales, the fast timescale model is built first with a bilinear form, and then the slow timescale model is induced from the fast one, specifically, with a bilinear-like form. After a simplified replacement made for the bilinear-like part, this problem can be solved by a convexification method. Extensive numerical experiments have been conducted to validate the effectiveness of this model.

Sign in / Sign up

Export Citation Format

Share Document