A plate model to account for the genetic relation between great volcanic eruptions and earthquakes which occurred along the Sagami trough branching off from Japan trench, and along the Nankai trough off the Chubu district is proposed on the basis of the newly compiled neotectonic map.
The northwestern Philippine Sea plate is bounded by the Nankai trough to the west and by the Sagami trough to the north. The Nankai trough is regarded as an active subduction zone in recent geologic time. So the Philippine Sea plate moves northwestwards in parallel with the Sagami trough. Consequently, the Sagami trough is regarded as a transform fault of trench-trench type which joints the Nankai trough and Japan trench. On a cross section of the northwestern Philippine Sea plate cut parallel to the Sagami trough, the Nankai trough, Oshima Volcano, Miyakejima Volcano, and the Izu-Bonin trench stand side by side from northwest to southeast. Large cracks for rising magma are expected to locate below these volcanoes, thereby dividing the plate into three segments (P₁, P₂ and P₃ from east to west in Fig. 7) in the cross-section. P₁ is pushed by a northwestward motion of the Pacific plate, therefore, at the first stage, the eruption of Miyakejima Volcano may occur owing to squeezing of magma beneath the volcano in response to the stress generated by P₁, and eventually, the bottom floor of the summit crater of Oshima Volcano may start to rise up. Secondly, the bottom floor of the summit crater may come up owing to the successive compressive stress generated by P₂ together with P₁, and then a great and/or large eruption of Oshima Volcano may occur. Thirdly, the Philippine Sea plate moves further northwestwards and then a great earthquake may occur to release the strain accumulated along the Sagami trough. Since such a continuous process is repeated several times, the Philippine Sea plate may go down beneath the Nankai trough where a greater earthquake may inevitably occur as the result. In fact, epicenters of recorded great earthquakes of M≥7.5 are located in a limited area along the Sagami trough and in the just inner parts of the Nankai trough. Evidently, greater earthquakes of M≥8.0 have mainly occurred in the latter province.
The plate model can well be applied to explain the genetic relation of the recorded eruptions and earthquakes in the studied region. Added to the facts, recent vertical crustal movement of the southern Kanto district also supports the model inferred from these events. So that, mutual relationship among eruption, earthquake and recent crustal movement may be an excellent clue to predict the coming great earthquake. Further detailed discussion is summarized as follows.
1) It is concluded with full confidence that great and/or large eruptions of Oshima Volcano in the last 200 years have occurred in 2 to 14 years after the eruptions of Miyakejima Volcano. The large eruption of Miyakejima Volcano occurred in 1962, from which that of Oshima Volcano will ensue in the next time. Added to the fact, the proper activity of Oshima Volcano must have started itself since 1972, based on seismicity of volcanic earthquakes in and around Oshima Volcano.
2) Judging from that the bottom floor of the summit crater of Oshima Volcano is regarded as risen up since around 1960, and that the strain has been accumulated based on the observation of the recent crustal vertical movement at Aburatsubo in the Miura Peninsula and the bottom floor may soon come to the peak position as shown in Fig. 11. The coming great and/or large eruption of Oshima Volcano might be expected to start from around a last half of 1970's by all above accounts.

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本稿は，朝鮮民主主義人民共和国の党営企業グループの形成過程，そして党営企業グループの傘下企業の構成，さらに党営企業グループと国家の計画経済に基づく一般経済との関係について分析し，党営企業グループの活動の特徴を明らかにするものである。党営企業グループの形成過程に関しては，1960年代に党直営の貿易会社である大聖貿易会社が設立されたこと，また，一般経済部門の生産機関から党の直営に移管されて輸出専門工場になった沙里院タオル工場の例が示された。そして，1970年代に党財政経理部39号室，平壌市党委員会や党軽工業部などで大聖，金剛，綾羅島，烽火などの企業グループが形成されて活動資金を蓄積するようになったことが示された。党企業グループの傘下企業に関する分析から，金のインゴットやマツタケ，ベニズワイガニに関して，党営企業グループの独占状態があることなどが確認された。その一方で，船興食料工場が党軽工業部の企業グループから一般経済部門へ移管された例や党行政部の活動資金が一般経済部門の養鶏工場に投資された例，39号室の資金で建設された平壌樹脂鉛筆工場，祥原セメント連合企業所など，党営企業グループあるいは党営企業グループの資金が一般経済に生産的な貢献をしている例により，党営企業グループが一般経済部門から一方的に資源を吸い上げているという従来の見解が正確ではないことが示された。

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It seems that wars in the 21st century are mainly in the form of Cyber Warfare rather than a more conventional style of confrontation. Cyber Warfare breaks out without declaration. Therefore, under the current Japanese legal system it is difficult to prevent Cyber Warfare, which is fought in the lawless zone called Cyberspace. If there were any legal regulations, such as international treaties, these laws would be broken easily with the new technology that is available. This paper tries to analyze how different nations tackle Cyber Warfare and how Cyber Warfare could be interpreted legally. It also makes several how suggestions on the Japanese defense policy against Cyber Warfare.

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本稿は，朝鮮民主主義人民共和国の兵器工業の発展過程と武力機関および兵器工業関連部門の企業による経済活動の拡大過程を示すことを通じて，従来充分な裏付けがなされてこなかった「軍事経済」論の有効性を検証するものである。兵器工業の発展に関しては，平壌での兵器工場の建設に始まり，それが朝鮮戦争時に分散疎開していくつかの工場になったこと，1960年代から兵器の高度化が進められたことが示された。とくに電子分野での武器の高度化においては熙川の電子工業の建設などで中国の協力が大きな役割を果たしていたことを指摘した。武力機関および兵器工業関連部門の企業による経済活動については，1970年代に軍隊での自給を目指す副業生産の拡大とは別個に輸出品を生産するようになったことが示された。さらに，近年，武力機関および兵器工業関連部門の企業が，従来行わなかった国内消費者向けの製品の生産やサービスの提供を始めるようになったことも指摘された。「軍事経済」論でいわれてきた武器生産体系と武力機関による国家計画外での経済活動の存在は兵器工場の建設状況，武力機関および兵器工業関連部門の貿易会社の組織状況によって確認された。

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