ABSTRACT
The chaotic response of the US Strategic National Stockpile to COVID-19 during 2020 highlighted the inadequacy of the inventory-based approaches to disaster response. This paper examines the integration of stockpile inventory, backup capacity, and standby capability to meet the disaster-related surge in demand in the future. We present a two-period model of such an integrated system for consumable items with uncertain demand that follows a general probability distribution. Our model incorporates standby capability in period 1 that can be converted to additional capacity for use in period 2, with the conversion yield being deterministic or stochastic. Our main results are: (1) Adding capacity in addition to inventory is beneficial only when the capacity reservation-related costs are relatively lower than the inventory-related costs. In this case, adding capacity will decrease the inventory needed in both periods, the shortfall probability, and the total expected cost. (2) Adding capability in period 1 is cost-effective only when the ratio of capability-development cost to conversion yield is lower than the capacity reservation cost. In this case, investing in capability results in less inventory and less reserved capacity in period 2. (3) Higher uncertainty in capability conversion yield reduces the attraction of developing capability in period 1. Consequently, less capability would be developed in period 1, while more inventory and capacity would be needed in period 2 in the face of a higher shortfall probability. © 2022 Production and Operations Management Society.
ABSTRACT
What comes along with the repeating and wide-range COVID-19 outbreak is the increasingly latent supply disruption risk encountered by global supply chains. Among many instruments to enhance supply chain resilience, backup production may be an appropriate choice, whereas how to induce the supplier backup becomes an obstacle. In this study, we investigate a supply chain in the context of the crisis-like new normal with supply disruption risk, wherein a manufacturer uses private demand information as a strategic lever, according to which a supplier decides whether to adopt backup production. Our findings reveal that the supplier's equilibrium decision on the adoption of backup production exhibits a cutoff structure when the manufacturer shares demand information. Moreover, we uncover the effect of information sharing on backup decision. In specific, information sharing impedes the adoption of backup production under low demand potential while promoting it under high demand potential. Interestingly, the manufacturer may have the incentive to share the demand information with the upstream supplier if the demand variability is low and the backup cost is moderate, and such information sharing stimulates the supplier to adopt the backup production. Counterintuitively, the manufacturer and the whole supply chain may display nonmonotonic relations to the backup cost as a result.
ABSTRACT
The chaotic response of the US Strategic National Stockpile to COVID-19 during 2020 highlighted the inadequacy of the inventory-based approaches to disaster response. This paper examines the integration of stockpile inventory, backup capacity, and standby capability to meet the disaster-related surge in demand in the future. We present a two-period model of such an integrated system for consumable items with uncertain demand that follows a general probability distribution. Our model incorporates standby capability in period 1 that can be converted to additional capacity for use in period 2, with the conversion yield being deterministic or stochastic. Our main results are: (1) Adding capacity in addition to inventory is beneficial only when the capacity reservation-related costs are relatively lower than the inventory-related costs. In this case, adding capacity will decrease the inventory needed in both periods, the shortfall probability, and the total expected cost. (2) Adding capability in period 1 is cost-effective only when the ratio of capability-development cost to conversion yield is lower than the capacity reservation cost. In this case, investing in capability results in less inventory and less reserved capacity in period 2. (3) Higher uncertainty in capability conversion yield reduces the attraction of developing capability in period 1. Consequently, less capability would be developed in period 1, while more inventory and capacity would be needed in period 2 in the face of a higher shortfall probability.
ABSTRACT
Only vaccination can not prevent COVID-19 infection. Social distancing and other preventive measures like - frequent hand washing, wearing a face mask can reduce the rising infection rate of COVID-19. It is not feasible to maintain social distancing and ensure hand sanitization in public places by humans as COVID-19 can affect that person or be contaminated by him/her. An automated social distancing system will play an essential role in maintaining social distance within certain boundaries. An automatic social distancing system called 'COV-SSDS' has been proposed in this work. In COV-SSDS, a person has to disinfect the hands with a sanitizer after being detected by the infrared sensor because the servo motor control door does not open without hand sanitization. If the person does not stand in the proper place, he/she will be notified. A liquid crystal display module has been used to display the number of people in the queue and the occupied slots. An alert generation system to alert the people about occupying the empty slot and a power backup unit was also attached to this system which was not found in previous studies. According to the features, feasibility, maintenance, and cost analysis, 'COV-SSDS' is worthy of the previous works. © 2022 IEEE.
ABSTRACT
The vulnerability of supply chains is more evident during crises. Recently, the COVID-19 pandemic, container ship blockades, and marine traffic jams in the Suez Canal have caused severe supply disruptions. Additive manufacturing (AM) often referred to as 3D printing, at demand sites, can solve supply disruptions. This study investigates how AM in different configurations affects supply availability. To this end, we simulate a healthcare supply chain. The simulation considers daily business demand and operational and disruptive supply risks. We measure demand, orders, stock levels, and availability indicators and compare them across supply configurations. The simulation allows identifying the most effective resilience configuration related to the cost-per-availability ratio. Overall, simulations support using AM as a risk-mitigation strategy. Copyright © 2022 Inderscience Enterprises Ltd.
ABSTRACT
Emergencies such as the COVID-19 and natural disasters have brought severe ordeals to the current grid emergency dispatch system, and there is an urgent need to improve and consummate the existing backup dispatch system. This paper firstly analyzes the existing three kinds of backup dispatch systems and their advantages and disadvantages, and then compares in detail the construction of national dispatch, provincial dispatch, and prefectural dispatch, and points out several existing problems of backup dispatch at all levels under the current emergency system. In order to gradually solve these problems, a backup dispatch system combining emergency and disaster recovery has been proposed based on the two-place three-center mode, it gradually realizes the prevention of risks from social security incidents such as public health incidents and serious natural disasters. © 2022 IEEE.
ABSTRACT
Having power sources close to the end user establishes resilience in the event of power outages. In order to effectively mitigate any risk of losing power and productivity, major office buildings usually have some sort of backup generation to sustain a business. Homes generally do not have a robust back-up power system, so when a person is working from home and the power goes out, productivity stops. Therefore, a new power grid solution is needed. Coming from the metric prefix atto, meaning 10-18, an atto-grid provides power to a singular room or section of room which makes it even smaller than a picogrid. This atto-grid powers the typical load of a standard, single-person office: a printer, a laptop, a phone, and a lamp. The atto-grid project was proposed by Dr. Robert Kerestes from the Electrical and Computer Engineering department at the University of Pittsburgh as part of a senior design course, and required distributed generation, connection to the building electrical grid, and a monitoring system for volts, amps, and watts. With these requirements in mind, the senior design team was able to design the atto-grid with two types of distributed generation, an inverter, manual switches and contactors for isolation, and accessible outlet receptacles for users to supply power to their at-home office load. An economic cost-benefit analysis was conducted as well for the purpose of determining the atto-grid's availability to different income levels. For hardware, results of tests on power quality and uptime will be presented;for software, metrics covering response time and accuracy will be analyzed and discussed. Finally, the budget, timeline, and expectations from the department faculty and domain advisors are discussed. Throughout the design process and semester, the design team learned technical and practical lessons that were brought up due to the semester coinciding with the COVID-19 pandemic. Despite technical and practical challenges, the team delivered on all requirements from the senior design curriculum, as well as the technical requirements based on the project proposal. The team acknowledges ways to improve the design if constraints were different, such as time, budget, and skillset. Finally, this paper will discuss feedback received from faculty and domain advisors throughout the semester, as well as reflect on progress and achievements for the atto-grid project. © American Society for Engineering Education, 2021
ABSTRACT
BACKGROUND: Coronavirus disease 2019 (COVID-19) infection has caused huge impacts on all of people's lives and health systems. In response to the COVID-19 pandemic, China was the first country to impose lockdown. We aimed to study the influence of COVID-19 on the outpatient visits of rheumatic patients in a non-outbreak area of China. METHODS: We selected three provincial or ministerial hospitals in Jinan, and collected the outpatient appointments data in rheumatology and immunology departments during the Shandong Province first-level public health emergency response period from 25 January 2020 to 8 March 2020. RESULTS: In the early stage, the number of outpatient appointments in the rheumatology and immunology departments of the three provincial or ministerial hospitals were significantly reduced, and gradually restored in the late stage. It showed that in the face of major infectious diseases, strict quarantine measures with the cooperation of the public not only controls the epidemic in a short time, but also lifts the quarantine measures and opens general outpatient clinics in hospitals as soon as possible, thus minimizing the impact on other patients. INTERPRETATION: The impact on the western hospital was greater than that on the Chinese medicine hospital, and the impact on the back-up designated hospitals for COVID-19 was the greatest. Online appointment can reduce the risk of infection in outpatients, but not completely solve the follow-up problem of rheumatic patients. Telemedicine provides a new solution for both management of rheumatic patients and control of COVID-19.