巻号一覧
36 巻 (1990)
- 4 号 p. 219-
- 3 号 p. 143-
- 2 号 p. 73-
- 1 号 p. 1-
36 巻, 1 号
選択された号の論文の6件中1～6を表示しています
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関口 直甫1990 年 36 巻 1 号 p. 1-6
発行日: 1990/03/25
公開日: 2011/03/01
ジャーナル フリー極運動の"微視的チャンドラー周期"を,1983-88年の6年間の地球回転パラメーターの観測値を使用して求めた.極運動は励起極の確率過程的運動によって励起されるという仮定のもとにその標準誤差を求めた.年周項は重ね合わせ法により求めて,極位置から差し引いた.また観測値に含まれている無秩序誤差の影響も補正した.結果は414.4±5.0(標準誤差)(単位:平均太陽日)となった.抄録全体を表示PDF形式でダウンロード (598K) -
村上 亮1990 年 36 巻 1 号 p. 7-22
発行日: 1990/03/25
公開日: 2011/03/01
ジャーナル フリー北米大陸上で追跡されたデータをもとにして行われた,GPS衛星の軌道決定について報告する.この軌道決定は著者が開発したGPS軌道決定手法の有効性を確:認するために行われた.この軌道決定手法では,決められた軌道が,搬送波位相を干渉させて位置を求めるGPS相対測位に最適化さたものとなるように,わが国上空の追跡データと諸外国で取得されたデータとを同時に用いるうえ,搬送波位相と擬距離とを同時に使用している.今回は,CIGNETと呼ばれる国際追跡網に含まれる北米大陸上の観測点のデータを使用して一連の軌道決定計算が行われた.その結果,この軌道決定手法によって,衛星配置が良好でないにもかかわらず,10-6程度の相対精度が達成されることが確認され,GPS衛星決定において,位相の二重差と擬距離を同時に解析することの有効性が実証された.抄録全体を表示PDF形式でダウンロード (1721K) -
村田 一郎, 笠原 稔, 山本 明彦, 市川 隆一, 三浦 哲, 立花 憲司, 中尾 茂, 仁田 交市, 藤井 陽一郎, 長坂 健一, 金沢 ...1990 年 36 巻 1 号 p. 23-36
発行日: 1990/03/25
公開日: 2010/09/07
ジャーナル フリーThe Sagami Bay area, south Kanto, Japan, is one of tectonically most active areas in Japan, where the Philippine Sea plate converges toward continental plates from southeast with a rate of about a few cm a year. Crustal activities including large inter- and intra-plate earthquakes and volcanic eruptions have suffered the area in historical ages. Thus, the monitorings of crustal deformations are most important in the area for both tectonic studies and prediction researches. In order to monitor the crustal deformation in this area, the interferometric technique of Global Positioning System is applied in the area. For this purpose, the research group of crustal deformation at many Japanese universities organized a consortium and deployed more than 30 GPS receivers aronud the Sagami Bay area. The campign was conducted from December 13 to December 17, 1988. 16 Trimble 4000SD, 5 MiniMac 28166 and 10 WM101 receivers were used and about 40 people in total participated in the observation. A three hours' session each day was scheduled so that four satellites may be tracked. However, the satellite constellation at the time of the campaign was not so favorable for accurate baseline determination, that only about 40 minutes in which four satellites were tracked simultaneously were available. MiniMac's were used for connecting the network with the SLR fiducial sites at Shimosato. Because the SLR station is roughly 300 km away from the network and the baseline determination accracy is roughly 1 ppm with unfavorable satellite constellation at the time of the observation, positions of other sites may be constrained with several tens of cm's accuracy. Trimble 4000SD receivers which are dual frequency were distributed to cover the area widely with 30 to 150 km baseline distances. Preliminary baseline analysis of the data show roughly 1 to 2 ppm short term repeatability. On the other hand, WM101 receivers which are single frequency were deployed in narrower area with baseline distances of 10 to 60 km considering the low accuracy of single frequency type. Baseline analysis showed about 4 ppm short term repeatability.抄録全体を表示PDF形式でダウンロード (1495K) -
大野 重保1990 年 36 巻 1 号 p. 37-50
発行日: 1990/03/25
公開日: 2011/03/01
ジャーナル フリーThe main objective of the present work is to present methods to obtain detailed surveys of the shape of the quasigeoid from the point of view of three-dimensional constructing and rigorous computing of the astrogeodetic network. In the most general case we can construct a high-precision astrogravimetric leveling network such as first-order geometrical leveling network. Inside each circuit of the astrogravimetric leveling network we can interpolate quasigeoid heights by using Stokes formula. From such a point of view the accuracies of detailed surveys of the quasigeoid height have been evaluated and practical methods to obtain the surveys in Japan whose accuracies are necessary and sufficient for our purpose have been discussed. Finally the construction of astrogravimetric continuous network and its simultaneous adjustment with the astrogeodetic continuous network of Japan is proposed.抄録全体を表示PDF形式でダウンロード (1326K) -
― 観測装置に起因する部分の発生原因と除去方法―山本 英二, 大久保 正1990 年 36 巻 1 号 p. 51-62
発行日: 1990/03/25
公開日: 2010/09/07
ジャーナル フリーAtmospheric pressure effects on the tilt observation using the borehole tiltmeters seem to consist of the substantial part through actual ground deformation and the apparent part induced by the instrumental effect. So far as both parts are mixed, it is impossible to discuss the atmospheric pressure effects quantitatively. At first, the latter part must be eliminated by making its cause clear and improving necessary points. For this purpose, the following experimental investigations were carried out at Honkawane station.1) Sealing the observation well, gaseous pressure change was applied into the well to get the simultaneous tilt changes of 3.5 nano radian/hPa in NS component and 10.0 nano radian/hPa in EW component. Including polarities, these responses were almost as same as the atmospheric pressure admittances obtained by the previous study, 2) Keeping to seal and thermally insulating the top part of the well, routine observation was continued for about 20 days to find that the tilt change associated with atmospheric pressure change was drastically diminished.3) Hanging up the sensor vessel a few centimeters above the bottom of the well, pres-sure change was applied by changing the water level in the well to get the same as 1). The above experiments 1) and 2) were also performed at a few other stations, and similar tilt changes were detected. These results indicated that the most of the atmospheric pressure effects were caused by the sensor vessel deformation. So, as a next step, the reform of the vessel was planned on a few points to increase its rigidity, such as to fatten the vessel, to insert a metal block between the tiltmeter and the seismometer, which were linked together in the vessel and formed a long system. This reform was made at four stations by Feb., 1990. As a result, most of the pressure admittances were decreased to the values less than 1 nano radian/hPa and signal to noise ratios were greatly improved. Now, we can distinguish the tilt change associated with the atmospheric pressure induced ground deformation and evaluate them quantitatively.抄録全体を表示PDF形式でダウンロード (1608K) -
萩原 幸男1990 年 36 巻 1 号 p. 63-64
発行日: 1990/03/25
公開日: 2010/09/07
ジャーナル フリーAssuming that the non-Newtonian gravitational potential has a Yukawatype term, I introduce mathematical formulas of the non-Newtonian attraction force of simply-shaped bodies.抄録全体を表示PDF形式でダウンロード (622K)
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