The COVAX program is expected to deliver at least 2 billion doses of vaccine worldwide by the end of 2021. 1.3 billion will be sent to 92 low-income countries participating in the program, bringing the vaccine rate of these countries to 20% of the population. Its vaccination can be roughly divided into three stages. In the first stage, medical staff and social care workers who need to take care of patients give priority to the vaccination rate of 3%. In the second stage, age over 65 and those whose disease has high risk are in danger of COVID-19 need to achieve a 20% vaccination rate. In the third stage, other priority groups will be gradually opened to further increase the vaccination rate.

There are various types of such vessels across industries depending on their design. But one factor that cuts through all the vessels of this nature is the purpose for real operation.

A pressure tank is a maintained device for water pressure. There is an air pre-charge inside like car tires. The air pressure inside the pressure tank is separated by a rubber diaphragm with the water pressure to maintain the water pressure in the system. The expansion Tank is usually much smaller compared with the water supply pressure tank. The expansion tank is used to absorb the water or thermal liquid expansion.

A key to selecting the right size pump is to figure the gallons per minute of water required at peak periods. A pump should be selected to meet normal peak demand for the household, rather than average use. There are two common methods for sizing a residential pump system.

In early September 2021,  Morten Engelstoft, CEO of APM Terminals, a port and terminal operator under Maersk, pointed out that due to the previous relief package promoted by the United States, the demand for goods has risen, which has further evolved into a vicious cycle of commodity shortages. In July 2021, compared with the same period last year, imports increased by 20%. This also means that there will be a large number of commodities entering, causing extremely tight port capacity, warehouses, and manpower, making the situation in port congestion worse.