Various rally events in Japan were canceled or postponed since mid-February 2020 due to the impact of the new coronavirus COVID-19 which was confirmed in late 2019. In Japan, February and March are the months when many conferences and research meetings are held. The authors were key-persons to bring the conference/research meeting online from late February to mid-March. Over 100 to 1,000 participants attended each conference. Each conference consists of a single session to a maximum of 13 parallel sessions. This paper discusses the prospect of the conference and summarizes the decision-making process and technical decisions of the conferences.