**1. Introduction**

According to the General Statistics Office of Vietnam's logistics industry, in the first 10 months of 2020, 4513 transport and warehousing enterprises were newly established (down 5.5% compared to 2019). A total of 2366 transport and warehousing enterprises dissolved. Cargo transport reached 1.43 billion tons of goods, (down 7.5% compared to 2019) [1]. The COVID-19 pandemic had many negative effects on businesses, industries, countries, and the whole world. Specifically, when the COVID-19 pandemic occurred, infected workers had to take leaves of absence for treatment, which affected the production and business situation of factories that were halted. In addition, the most impactful factor is the social distancing orders of localities. This complicated the situation of transporting goods and materials in factories, causing supply chain disruptions and breach of contracts with partners, seriously affecting the logistics industry of countries.

The logistics chain involves sea transport, rail transport, water transport, and road transport; and activities in transportation, loading, unloading, forwarding, and storage (shown in Figure 1) [2]. If managers can come up with solutions to reduce these costs by maximizing both directions of routes and improving the occupancy rate at warehouses, it will help businesses improve results. Considering those problems, the questions are: How does the COVID-19 pandemic affect the business situation of logistics enterprises in Vietnam? The pandemic affects which areas in logistics activities? Are there any solutions to help logistic businesses grow after the pandemic? Are there any cost-saving solutions for logistics businesses? In this context, the authors realize that it is necessary to specifically assess the impact of the pandemic on the business performance of logistics enterprises, and

**Citation:** Nguyen, H.K. Application of Mathematical Models to Assess the Impact of the COVID-19 Pandemic on Logistics Businesses and Recovery Solutions for Sustainable Development. *Mathematics* **2021**, *9*, 1977. https://doi.org/10.3390/ math9161977

Academic Editor: Mikhail Posypkin

Received: 20 July 2021 Accepted: 14 August 2021 Published: 18 August 2021

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it is necessary to find solutions to limit the risks of the epidemic to all stakeholders. It is necessary to research and propose solutions to help logistics enterprises in Vietnam restore and stabilize their business situations, help businesses ensure reasonable growth, stabilize jobs for employees, and create a foundation for rapid and sustainable economic growth.

**Figure 1.** Dual channel network structure in Logistics (Liu et al., 2020).
