@article{oai:nagasaki-u.repo.nii.ac.jp:02000506, author = {藤田, 渉}, issue = {1-3}, journal = {経営と経済, Journal of Business and Economics}, month = {Dec}, note = {The global turmoil caused by the novel coronavirus (COVID-19) has led to curfews and travel restrictions in many countries. This disrupted production in many countries, caused ports and other places to shutdown, and had a significant impact on modern economic systems that rely on multilateral supply chains. This also had a significant impact on Japan, bringing unprecedented changes to the international trade environment of Japan, which is heavily dependent on international supply chains, including disruptions at loading ports, destinations, ports and transportation, and domestic production and transportation. In particular, the import disruption has also affected the employment situation. From the perspective of imports, the fluctuations in the import value of each industry may seem uncorrelated at first glance, but if we consider it as an irregular oscillation caused by the propagation of many internal and external factors, the fluctuation of the import value is due to the trend based on actual data, the real value signal, alone lacks phase information. Therefore, we converted the data into an analitic function using the Hilbert transform and applied CHPCA (Complex Hilbert Principal Component Analysis). As a result of the analysis, it was found that during the period when the impact of COVID-19 in the Japan was large, there was a special tendency compared to the period before and after it, and it was likely that multiple vibrations occurred while influencing each other., 赤石孝次教授定年退職記念号, In Honour of Prof. Takatsugu Akaishi, 経営と経済, 103(1-3), pp.79-149; 2023}, pages = {79--149}, title = {COVID-19ショックによるグローバル・サプライ チェーンとわが国の雇用への影響}, volume = {103}, year = {2023} }