[Article]　
　　
◆ Relationship between transpolar flights over the Arctic and the upper atmospheric circulation ‥‥‥‥‥‥ 1 – 6　　
　　　　Kazutoshi SATO (Kitami Institute of Technology) and Jun INOUE (National Institute of Polar Research)　　　　　　(doi.org/10.57287/ospor.3.1)
　　　　

◆ Utilization of discarded and unused woody materials for biomass heating and ‥‥‥‥7 – 12
　power plant 　
　　　　Tsuyoshi YODA (City of Mombetsu/Japan/Hirosaki Industrial Research Institute,
　　　　Aomori Prefectural Industrial Technology Research Center)　　
　　　　　　　　（doi.org/10.57287/ospor.3.7）
　　　　
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◆ Turning features of an icebreaker during ramming operations: a case study ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ 13 – 19
　　　　Yuto TAKAHASHI, Hajime YAMAGUCHI (Graduate School of Frontier Sciences, The University of Tokyo),
　　　　Shuki USHIO (Meteorology and Glaciology Group, National Institute of Polar Research), Yutaka YAMAUCHI and
　　　　Shigeya MIZUNO (Technical Research Center, Japan Marine United Corporation)　　　　　
　　　　　（doi.org/10.57287/ospor.3.13）