All issues
Volume 23 (2013)
- Issue 4 Pages 278-
- Issue 3 Pages 199-
- Issue 2 Pages 99-
- Issue 1 Pages 6-
Volume 23, Issue 4
Displaying 1-4 of 4 articles from this issue
- |<
- <
- 1
- >
- >|
-
Hiroomi IMAMOTO, Mitsuyoshi TASAKU, Eiichi FURUSATO2013 Volume 23 Issue 4 Pages 278-289
Published: December 16, 2013
Released on J-STAGE: March 15, 2014
JOURNAL FREE ACCESSArtificial circulation systems using bubble plume were installed in nine eutrophicated reservoirs, cyanobacterial bloom and musty odor phenomenon occurred every year. After the installation of the systems, the cell density of Microcystis decreased and cyanobacterial blooms were prevented. However, the effects on the musty odor caused by cyanobacteria, such as Oscillatoria and Phormidium, differ depending on reservoirs. Based on the these results, we proposed the optimized design and management methods of the artificial circulation system for preventing cyanobacterial bloom and musty odor caused by cyanobacteria. We also discussed the limitations of the system for preventing harmful cyanobacterial growth.View full abstractDownload PDF (1409K) -
Fuminori KIMURA, Takamitsu HOMMA, Ken USHIJIMA, Eiichi FURUSATO, Yasus ...2013 Volume 23 Issue 4 Pages 290-299
Published: December 16, 2013
Released on J-STAGE: March 15, 2014
JOURNAL FREE ACCESSThere are many ambiguities in the musty odor problem in the dam reservoirs, although many studies have been conducted. As one of the main causes, very similar morphological species were coexisted in the Oscillatoriales (Cyanophyta) including both the musty-odor producing species and the non-musty-odor producing species. However, the musty-odor producing species can not be identified by the present morphological identification technique or the separation of green / brown strains using a fluorescent microscope. This report introduces the consideration on development of new morphological identification technique to identify musty odor-species, and the view and issues on the practical application of its.View full abstractDownload PDF (1154K) -
Takayuki SANO, Koichiro OTAGAKI, Nobuteru SATO2013 Volume 23 Issue 4 Pages 300-309
Published: December 16, 2013
Released on J-STAGE: March 15, 2014
JOURNAL FREE ACCESSGravity dam gateposts have been no damage against large seismic motion. But in ever dynamic analysis, we often have the result that dam gatepost will get damage against level2 seismic motion. When the 2011 earthquake of the Pacific coast of Tohoku had happened, strong motion observed at Takashiba dam site. Using the seismic record at Takashiba dam, we calculated dynamic behavior of dam gatepost. We proved that gatepost motion restrict by the materials for seal between gatepost and girder of bridge in 3 dimension dynamic analysis.View full abstractDownload PDF (1266K)
-
Nobuharu MEGURO, Yasunori SHOJI, Ryouji FUKAMITU, Masahito KOBAYASHI, ...2013 Volume 23 Issue 4 Pages 310-317
Published: December 16, 2013
Released on J-STAGE: March 15, 2014
JOURNAL FREE ACCESSWith recent changes in water use and diversification of the role of dams, an increasing number of dams have been renovated. The Kurokui-gawa Dam was constructed in 1969 as a concrete gravity dam. This paper outlines the work for renovating the Kurokui-gawa Dam from the excavation of the dam to the construction of a cofferdam, installation of outlet pipes and closure of the dam, and describes the method of construction, measurement of vibration during excavation of the dam and high-flow concrete used for closure.View full abstractDownload PDF (1634K)
- |<
- <
- 1
- >
- >|