Author 岡山大学環境理工学部広報委員会|
Published Date 2009-03-16
Publication Title 岡山大学環境理工学部研究報告
Volume volume14
Issue issue1
Content Type Others
Author 岡山大学環境理工学部広報委員会|
Published Date 2009-03-16
Publication Title 岡山大学環境理工学部研究報告
Volume volume14
Issue issue1
Content Type Others
Author 岡山大学環境理工学部広報委員会|
Published Date 2009-03-16
Publication Title 岡山大学環境理工学部研究報告
Volume volume14
Issue issue1
Content Type Others
Author 岡山大学環境理工学部広報委員会|
Published Date 2009-03-16
Publication Title 岡山大学環境理工学部研究報告
Volume volume14
Issue issue1
Content Type Others
JaLCDOI 10.18926/fest/15046
Title Alternative Transition of Arable Land Use in Okayama Prefecture
FullText URL 014_029_036.pdf
Author Ichiminami, Fumikazu|
Abstract In this study, a long-term transition on arable land use and planted acreage in Okayama prefecture is mainly examined. There were no substantial changes at the area of the cultivated acreage and the use level of arable land before World War II. In statistics after 1965, the use level of the cultivated acreage and arable land has decreased remarkably. In this point, it is clearly observed that the cultivated acreage in 2005 has decreased by 60 percent compared with 1960 and the area of the field has importantly decresed in the same period about 80 percent. In addition, the uncultivated arable land in 2005 has increased double (or more) compared with 1975. Finally, this analysis concretely illustrated decreasing of man's concern for the production of food. Because a part of the safety of food is threatened recently, it is important in above all to procure food safely. Moreover, to reinforce a domestic production of food the decision and the execution of an effective policy are requested.
Keywords arable land use planted acreage food production Okayama prefecture
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 29
End Page 38
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002307591
JaLCDOI 10.18926/fest/15045
FullText URL 014_023_028.pdf
Author Chegbeleh Larry Pax| Nishigaki, Makoto| Akudago John Apambilla| Alim Md. Abdul| Komatsu, Mitsuru|
Abstract During underground space development, groundwater seepage mostly occurs which may seriously affect the stability of deep excavations as well as retard progress of construction. For smooth progress of work, effective construction and operation of a disposal facility for high level radioactive waste (HLW), it is important to control seepage into excavations by sealing off fractures or fissures and excavation disturbed zones (EDZ) to control groundwater inflow during the construction phase of such a facility. In this study, a series of experiments were conducted on ethanol/bentonite slurries in the laboratory with the aim of determining the effect of a hydrophilic solvent such as ethanol on the hydraulic and injection characteristic of bentonite slurry for the sealing of fissures to control ground water seepage during the construction phase of a repository. Preliminary results revealed ethanol/bentonite slurry as an effective grouting material capable of penetrating micro fractures (100μm or less) and with the permeability of the grouted medium being as low as 10E-7cm/s. The results also show that the effectiveness and efficiency of grouting is dependent on the type of injection and fissure size. Dynamic injection was observed to be efficient as it was able to inject high dense slurry.
Keywords Dynamic injection permeability swelling bentonite clay
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 23
End Page 28
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002307422
JaLCDOI 10.18926/fest/15044
FullText URL 014_017_022.pdf
Author Akudago John Apambilla| Nishigaki, Makoto| Chegbeleh Larry Pax| Komatsu, Mitsuru| Alim Md. Abdul|
Abstract Soil-groundwater salinity issues have assumed a worldwide dimension. It is believed that when groundwater level is less than 2 m there is the possibility of salinity transfer between the soil and groundwater due to factors such as capillary forces. One-dimensional column tests were conducted in the laboratory to find a suitable capillary cut design. The capillary cut material comprised a 20 cm thick 2–4.7 mm and a combination of 2–4.7 mm and 9.5–19 mm gravel material. In all, four different designs were tested by compacting Oji sand in the various columns. Groundwater level of 0.75 m from the top was maintained while salt solution of 10% concentration was allowed to flow under capillary forces through the columns. The water content in the columns were monitored using frequency domain reflectrometry-vector analyzer (FDR-V) after which soil samples from 10 m interval in each column was taken for electrical conductivity measurements. The results showed that 5 cm thick, 2–4.7 mm gravel sandwiching coarser material (e.g. 5 cm thick 9.5–19 mm or 10 cm thick 9.5–19 mm gravel material) proved to be very useful design to cut capillarity.
Keywords soil-groundwater salinity capillary cut filter media design
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 17
End Page 22
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002308001
JaLCDOI 10.18926/fest/15043
FullText URL 014_013_016.pdf
Author Alim Md. Abdul| Nishigaki, Makoto| Chegbeleh Larry Pax| Akudago John Apambilla| Komatsu, Mitsuru|
Abstract Soil-water characteristic curve (SWCC) is an important soil function in an unsaturated soil mechanics field for design and analyses of any unsaturated earth structures. Determination of SWCC is not easy and more so time consuming. Generally, ceramic disc with high air-entry value has been used in the pressure plate apparatus for this purpose by many people. Now-a-days membrane filter is being used as a suitable alternative to ceramic disc. However, experience shows, it has disadvantage of breakage after one time use especially with coarse grain soils (sandy soils). In this study, membrane filter with stainless wire mesh was used to solve this problem and the SWWC was compared with the results obtained without wire mesh. Results showed that membrane filter with stainless wire mesh can be used to determine the SWCC for coarse grain soils.
Keywords SWCC Unsaturated sandy soils Membrane filter Stainless wire mesh
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 13
End Page 16
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002307956
JaLCDOI 10.18926/fest/15042
FullText URL 014_001_012.pdf
Author Morimoto, Tomoko| Zenihana, Tomohiro| Maitani, Yusuke| Ishikawa, Hirofumi|
Abstract The spread of the highly pathogenic avian influenza (H5N1) among domestic poultry and wild birds has caused global concern over the outbreak of an influenza pandemic of H5N1. The "Pandemic Influenza Preparedness Action Plan" determines the strategy against an influenza pandemic in Japan. Simulations were carried out using an individual based model (IBM). The IBM targeted a virtual area with a population of 100,000 using the demographic data of Sapporo-city, Hokkaido. The effectiveness of targeted antiviral prophylaxis (TAP), geographical targeted antiviral prophylaxis (GTAP), school closure, and pre-pandemic vaccination were explored. Moreover, this study focused on infections among children, who have a high attack rate, and analyzed the effectiveness of interventions for school-age targeted antiviral prophylaxis (STAP). Consequently, TAP, which is recommended by the "Pandemic Influenza Preparedness Action Plan", was found to have high effectiveness in the suppression of the outbreak. Moreover, this study showed the importance of intervention among children, such as STAP and school closure, to prevent the spread of H5N1 influenza.
Keywords Influenza Pandemic H5N1 Individual Based Model (IBM) Sapporo
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 1
End Page 11
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002307373