著者

森田 裕一 酒井 慎一 中川 茂樹 笠原 敬司 平田 直 鏡 弘道 加藤 拓弥 佐藤 峰司

出版者

東京大学地震研究所

雑誌

地震研究所彙報 (ISSN:00408972)

巻号頁・発行日

vol.84, no.2, pp.89-105, 2009

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The Autonomous Cooperative data Transfer Protocol (ACT protocol) is one of the data transfer protocols based on UDP/IP developed for the Metropolitan Seismic Observation network (MeSO-net). It has a robust re-send function to prevent data from being lost in the Internet route. Moreover, it also has a function to adjust the data transmission rate considering the quality of the Internet route and the load on the data-receiving system. If the Internet route is too busy to send all data, the transmission rate from the observation station is decreased automatically to ease the Internet traffic jam, and data that cannot be sent because of the limitation on the transmission rate are stored at each station. After conditions recover, the stored data are sent automatically at an increasing transmission rate and gradually catch up with real-time data. The transmission rate is decided by data transmission equipment at the station using pre-loaded algorithms, not at the data center. Therefore, the load at data center equipment is not so high even if the equipment receives data from hundreds of stations. We describe an overview of the ACT protocol, flow charts, and data format used in the protocol. We also demonstrate that the ACT protocol is very powerful for the vast size of the seismograph network composed of several hundred stations. The ACT protocol is generally applicable and can be used for data transmission systems in other scientific fields.

著者

木股 文昭 石原 和弘 植木 貞人 内田 和也 小山 悦郎 佐藤 峰司 鈴木 敦生 高山 鐵朗 竹田 豊太郎 辻 浩 寺田 暁彦 中坊 真 浜ロ 博之 平野 舟一郎 松島 健 宮島 力雄 森 済 八木原 寛 山本 圭吾 渡辺 秀文

出版者

京都大学防災研究所

雑誌

京都大学防災研究所年報 (ISSN:0386412X)

巻号頁・発行日

vol.42, no.1, pp.35-43, 1999-04

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1998年以降, 火山活動が活発化している岩手山火山において, 火山活動に伴う地殻上下変動とその圧力源を議論する目的で, 水準路線を設置し, 1998年7, 9, 11月に精密水準測量を実施した。1998年9月3日, 水準測量実施中に, 直下でM6.1の地震が発生し, 20cmに達する断層運動を水準測量で検出した。岩手山南麓ではこの4ヶ, 月間に4cmに達する山側隆起の上下変動が観測され, その圧力源は岩手山西方に深さ3km前後と推定される。Earthquake swarm is observed around the Iwate-san Volcano, Northeast Japan since 1998. The leveling route with distance of 36 km was set up around the volcano and the precise levelings have been repeated to discuss the crustal deformation four times in July, September, September and November in 1998. When the precise levelingis doing in September 3, 1998, earthquake of M6. 1 was occurred close to the volcano. One leveling team was making leveling in the epicenter area, Re-levelings were repeated since the next day of the earthquake, and coseisimic deformations of 20 cm are detected along the leveling route. However the precursor of the vertical movements is not recognized in the leveling data made just before the earthquake. Uplift of the Iwate-san Volcano is observed and which amounts to 4 cm in the period of July to November in 1998. The pressure sources of the vertical deformations are estimated to be under the west side of the volcano with depth of 3 kim, which is the almost the same location of the pressure estimated by GPS measurements and the DInSAR (Differential Interferometric SAR).

著者

森田 裕一 酒井 慎一 中川 茂樹 笠原 敬司 平田 直 鏡 弘道 加藤 拓弥 佐藤 峰司

出版者

東京大学地震研究所

雑誌

地震研究所彙報 (ISSN:00408992)

巻号頁・発行日

vol.84, no.2, pp.89-105, 2009

---

The Autonomous Cooperative data Transfer Protocol (ACT protocol) is one of the data transfer protocols based on UDP/IP developed for the Metropolitan Seismic Observation network (MeSO-net). It has a robust re-send function to prevent data from being lost in the Internet route. Moreover, it also has a function to adjust the data transmission rate considering the quality of the Internet route and the load on the data-receiving system. If the Internet route is too busy to send all data, the transmission rate from the observation station is decreased automatically to ease the Internet traffic jam, and data that cannot be sent because of the limitation on the transmission rate are stored at each station. After conditions recover, the stored data are sent automatically at an increasing transmission rate and gradually catch up with real-time data. The transmission rate is decided by data transmission equipment at the station using pre-loaded algorithms, not at the data center. Therefore, the load at data center equipment is not so high even if the equipment receives data from hundreds of stations. We describe an overview of the ACT protocol, flow charts, and data format used in the protocol. We also demonstrate that the ACT protocol is very powerful for the vast size of the seismograph network composed of several hundred stations. The ACT protocol is generally applicable and can be used for data transmission systems in other scientific fields.