It is difficult at present to verify the distribution of radioactivities and to estimate their accumulation trends only from the results of environmental monitoring because of quite low level of effluent from nuclear power plants. Therefore, a mathematical model was developed to support the environmental monitoring as well as to predict the accumulation trends of radioactivities discharged into the environment. Then the model was simulated by applying on the behavior of ⁶⁰Co released from the nuclear power station located in the coast of Uchiura Bay, a part of Wakasa Bay.
The mathematical expression is composed of an estimation model for distribution of current velocities based on the results of field observations, a diffusion equation including the terms of advection, diffusion, appearance and disappearance, and a box model applied for some reaches. Adsorption on sediment and effect of scavenging are also taken into consideration. Details of the model are described in this paper and the validity is checked and discussed. The results of verification draw the conclusions as follows:
(1) On the concentration of ⁶⁰Co in the sediment only detectable near the discharge point, the values estimated and observed were agreed within a factor of three.
(2) It was estimated that the half amount of ⁶⁰Co released during 8yr after 1974 is accumulated in the bay sediment, whereas the other is lost away from the bay.
(3) The results of calculation showing no increase of accumulation at 1982 suggest nonprogressive accumulation in the future.

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本稿は, 関西電力 (株) 高浜発電所3・4号機の建屋建設におけるコンクリート工事について述べたものである。約40万m³の大量のコンクリートの品質を確保するとともに, 合理的な施工を行うために実施した工事計画, 材料, 流動化コンクリートの施工法, 品質管理および各種改善工法について紹介する。

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本研究では、地震波干渉法による共通仮想震源によるグリーン関数を用いた位相速度推定法の適用性を検討するために，若狭湾地域の16 地点で連続観測を実施し，相互相関関数のシグナルが大きい正側およびシグナルが小さい負側のそれぞれを用いた場合について，位相速度を推定しその結果を比較した。共通仮想震源から観測点への伝播に対応する側の相互相関関数のシグナルが明瞭な場合，共通仮想震源によるグリーン関数から安定して位相速度を推定することが可能であり，自然地震を用いた場合の位相速度とも調和的であった。一方，共通仮想震源からの伝播に対応する側の相互相関関数のシグナルが不明瞭な場合，位相速度の推定ができなかった。そこで，遅れ時間の正負を反転させた相互相関関数を共通仮想震源によるグリーン関数として用いた結果，良好に位相速度を推定できることがわかった。さらに，本研究のように相互相関関数が正負非対称となる場合には，シグナルが強くなる方向に観測点を配置することでも，位相速度推定が可能となることを示した。

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Special seminars on the “Present Situation of Japanese Macaques” were held four times between 1990-1993 and were aimed at making clear the situation of wild populations of Japanese macaques and establishing definite proposals for future management. The discussion in these seminars was summarized. In nearly half of the prefectures in Japan surveys of wild Japanese macaques were being conducted in some way. Recently, in most areas, macaques started to appear near cultivated fields and may be changing their behavior towards human beings, because they had usually fled in former days. It was reported that: some populations of Japanese macaques shifted themselves from the deep interior of mountains to be close to villages; the range of the groups became larger when they moved to fields to raid crops; the number of laborers decreased rapidly in the past two decades and their age became higher in Japanese agricultural villages which may be the principal factor allowing monkeys come closer to the field; hunting prohibited since 1947 may have affected the monkeys behavioral changes; the habitat disturbance (especially large-scaled plantation of coniferous trees in the mountain) might have induced the shift of monkey populations and so on. In Japan the organization of and/or persons monitoring the wildlife on a daily basis are scarcely available and the need for such organization or systems to make it realized was strengthened. Some other necessities are also mentioned.

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