測地学会誌
Online ISSN : 2185-517X
Print ISSN : 0038-0830
ISSN-L : 0038-0830
39 巻, 4 号
選択された号の論文の9件中1~9を表示しています
  • 福田 洋一
    1993 年 39 巻 4 号 p. 327-340
    発行日: 1993/12/25
    公開日: 2010/09/07
    ジャーナル フリー
    As the GPS survey directly determines the height of the Earth's surface from a reference ellipsoid, its combination with ordinary leveling and/or gravity measurements provides us several kinds of the gravity field quantities such as gravity anomaly, gravity disturbance and geoid height. Although these quantities have the same importance as the gravity field data, theoretically, it is meaningful to investigate the best practical ways of treating the data. We therefore present first a proper formulation by the least squares collocation as a mean to apply GPS, leveling and gravity data for a local problem, and then investigate the degree variances of the gravity field in Japan. We discuss subsequently the error estimates of the combined measurements, and finally conclude that the combined use of GPS and gravity data is quite efficient for both gravity surveys and height determinations.
  • 藤井 陽一郎
    1993 年 39 巻 4 号 p. 341-352
    発行日: 1993/12/25
    公開日: 2011/03/01
    ジャーナル フリー
    A special approach to adjust geodetic network in which GPS surveys are frequently repeated is performed with the aid of four-dimensional integrated adjustment technique. We take global Cartesian coordinate as a reference system, and assume not only coordinate unknowns but also rate of deformation signal linear with time. Observation equation for the repeated baseline measurements is proved to be a type of fundamental observation equation in least squares collocation. We deduced the solutions of deterministic approach for three cases in which (1) both design matrix and signal coefficient matrix are singular, (2) only design matrix is singular, and (3) signal coefficient matrix is singular. In solving the observation equation, we apply reduced normal equation for case (2) and (3). Further we discussed the solution of stochastic approach. In case of singular normal equation, we apply inner constrain matrix both for parameters and signals in order to obtain the unknowns. The adjusted results are transformed into the numerical values based on local Cartesian coordinate. Finally, horizontal strains are deduced from overdetermined horizontal displacement vectors at the GPS stations.
  • 真鍋 盛二, 原 忠徳, 亀谷 牧, 河野 宣之, 久慈 清助, 笹尾 哲夫, 佐藤 克久, 川口 則幸, Friedhelm Glasik ...
    1993 年 39 巻 4 号 p. 353-361
    発行日: 1993/12/25
    公開日: 2011/03/01
    ジャーナル フリー
     1990年9月にドイツのワイルハイムにK-4バックエンドシステムを日本から持ち込み鹿島34m及び野辺山6mアンテナとのネットワークでVLBI観測を行った.ワイルハイム30mアンテナによる観測はセンウムー水晶時計を用いたにも抱らず概ね良好であり,K-4バックエソドシステムの可搬性と信頼性が証明されたと考えられる.データは国立天文台水沢で関発されたソフトウェア(MSLV3)を用いて解析された.野辺山6m・アソテナの感度からくる制約と鹿島局における観測後半のシステム不良からワイルハイムの位置決定に使用できるデータは約半日分の鹿島―ワィルハイム基線データに限られた.ワイルハイムの位置決定の最終内部精度は約10cmであった・しかしながらこれは従来得られていたものより格段に改良されている.
  • 古澤 保, 大谷 文夫, 寺石 眞弘, 園田 保美
    1993 年 39 巻 4 号 p. 363-376
    発行日: 1993/12/25
    公開日: 2010/09/07
    ジャーナル フリー
    We carried out test observation of crustal strain by two extensometers on common bases in an observation vault of Takajo observatory at Miyazaki prefecture in Southwest Kyushu, Japan. These extensometers are composed of two different type invarrods, one of which is conventional super-invar (S-I) and the other is new super-invar whose coefficint of expansion is extremely lower than that of conventional one. The new S-I extensometer is less influenced by temperature changes in the vault. Especially in the periods showing large drift after installation of instruments and for the duration of rainfall disturbances, when the air temperature in the vault changes rapidly, the availability of the low coefficient of new S-I reveals evidently. Coefficient of linear expansion of both materials were numerically estimated from the observation data in the period of initial drift and from the heating experiments data. The coefficient of expansion of conventional S-I is about 1×10-6/°C and that of new S-I is less than 1×10-7/°C, sign of which changes according to the temperature.
  • 藤間 一郎, 瀬田 勝男, Brown Nick, Ciddor Philip E.
    1993 年 39 巻 4 号 p. 377-386
    発行日: 1993/12/25
    公開日: 2011/07/05
    ジャーナル フリー
     計量研究所で開発したHe-Neレーザのモード間ビートを利用する距離計によりオーストラリア連邦科学産業研究機構の野外測量基線の測定を行った.測定は20mから649mの距離で行われ,空気屈折率と周期誤差の補正後,649mの距離が±0.3mmの再現性で測定された.また,この測定結果を市販の高精度型距離計による測定と比較した.測定の前後に計量研究所トンネル内でビート式距離計の校正を行うことにより,両国の長距離測定の標準の間に矛盾の無いことを確認した.
  • ―水平変動ベクトルの新しい推定方法の応用―
    小牧 和雄
    1993 年 39 巻 4 号 p. 387-410
    発行日: 1993/12/25
    公開日: 2011/07/05
    ジャーナル フリー
     水平変動ペクトルの新しい推定方法として,最大せん断ひずみを拘束条件として用いる測地網平均法を開発した.この平均法により,物理モデルを用いずに,また,網をゆがめことなく網を自動的に固定することが可能である.さらに,この方法は,回転楕円体上の網に適用でき,拘束される点を自由に選ぶことができる.この方法を,雲仙火山の小規模GPS測量網に適用した結果,普賢岳の点が1990年11月と1991年2月との間に西方向へ12cm動いたことが分かった.また,一等三角測量(1882-1909)及び精密測地網測量(1973-1989)のデータを用いて,この方法を日本の全国的な一等三角網に適用したところ,プレート運動に起因すると考えられる地殼変動が得られ,日本列島の東北部と西南部とでは水平変動ベクトルのペターシが異なることが分かった.さらに,選ばれた固定点に対して水平変動ベクトルを変換することにより,プレート境界や構造線が存在すると考えられる地域の地殼変動が調べられた.この結果,東海地方の駿河トラフ,糸魚川―静岡構造線,男鹿―牡鹿構造線及び九州の別府―島原地溝周辺の特徴的な地殼変動が明らかにされた.
  • 山内 常生, 宮島 力雄, 奥田 隆
    1993 年 39 巻 4 号 p. 411-417
    発行日: 1993/12/25
    公開日: 2010/09/07
    ジャーナル フリー
    In observing crustal deformations, strain and tilt data are usually recorded in a continuous manner with a telemetry system using leased lines. However, this system is often disrupted by such troubles as interruptions in the power supply and problems with the leased line. In order to alleviate these problems, an automated measuring system has been designed. The system consists of a microcomputer containing a newly designed interface circuit and a panel meter for analog-to-digital (AID) conversion. The system operates with low power consumption and supports a long-term continuous observation utilizing only a car battery. The system is inexpensive, easy to handle. The data recorded by the system agrees well with that by the telemetry system, and the former is reliable not only for use of tidal analysis but also for use over long periods.
  • 瀬川 爾朗, 中川 一郎, 田中 寅夫, 志知 龍一, 加藤 照之, 横山 紘一, 馬場 義男, 我如古 康弘, 岡田 義光
    1993 年 39 巻 4 号 p. 419-424
    発行日: 1993/12/25
    公開日: 2010/09/07
    ジャーナル フリー
    In order to fully understand the state of the Earth's environment, extensive scientific efforts for detecting various phenomena on a global scale are necessary. Since geodesy is the science for measuring the Earth's configuration and deformation, its contribution to the Earth's environmental study is, as a matter of course, expected. At present, a number of institutions in Japan are engaged in such geodetical works as tidal measurement, leveling, space technology-based surveys (VLBI, SLR, GPS), absolute gravity measurement, superconducting gravity measurement, satellite altimetry, Earth rotation and polar motion measurement, and so on. They are also participating in numerous international observation programs and services. Considering the important role expected of these geodetic works, we recommend that they should be more effectively applied to the environmental study of the Earth.
  • GSI精密暦による基線解の長期再現性(1)高山―八丈基線における
    木股 文昭
    1993 年 39 巻 4 号 p. 425-427
    発行日: 1993/12/25
    公開日: 2010/09/07
    ジャーナル フリー
    Baseline vectors on Takayama-Hachijo baseline (412 km) were determined from daily GPS measurements using the GSI precise ephemerides. Results were compared with those determined using broadcast ephemerides in the period from April 1992 to January 1993. Longterm repeatability for ten months were improved to 14 mm (3.4×10-8) from 18 mm in N-S component, to 22 mm (5.3×10-8) from 57 mm in E-W, and to 63 mm (1.5×10-7) from 117 mm in U-D.
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