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JaLCDOI 10.18926/fest/11503
フルテキストURL 008_053_062.pdf
著者 A.M. Dewan| 西垣 誠| 小松 満|
抄録 Flood becomes regular feature in riverrine Bangladesh. Every year, around 21 percent of land is flooded during monsoon season, however, in severe situation this figure shot up to more than 60 percent of total land. This paper is an attempt to analyze hydrological characteristics of two catastrophic events (1988 and 1998 flood) in the light of flood history in Bangladesh. The analysis demonstrates that the 1998 flood was more severe than the 1988 one. Moreover, the 1998 flood was also prolonged than the 1988 flood due to heavy rainfall inside and outside of the country. Finally, flood management issues in Bangladesh have been analyzed and found that structural solution to mitigate flood is not the only solution. Based on the analysis some possible mitigation options are put foward.
キーワード Flood Flood Management Danger level Peak floods Deforestation
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 53
終了ページ 62
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313768
JaLCDOI 10.18926/fest/11502
フルテキストURL 010_083_088.pdf
著者 Kankam-Yeboah Kwabena| Darko Philip K.| 西垣 誠|
抄録 Groundwater has been recognised as the most cost-effective option of safe water supply to rural communities in Ghana. The demand for potable water has led to the drilling of a large number of boreholes in many parts of the country. To establish the threshold of groundwater development from storage in a major river catchment (Pra River) in South-West Ghana, studies on recharge to the weathered aquifer and statistical evaluations of specific capacity and potential yield have been carried out. The SACSMA conceptual hydrological modelling system was used for the recharge estimate. With recharge rate of 50 mm/yr, the natural groundwater resources in the basin was estimated to support a maximum withdrawal of 12 l/s for a 10 hour per day pumping. The groundwater resources potential of 1.6 l/sk㎡ could be considered the threshold of groundwater exploitation in similar river basins in South-West Ghana. A study into the relation between permeability and recharge under different conditions and scenarios is required to define their limiting role in groundwater resources development.
キーワード Groundwater storage recharge aquifer specific capacity base flow hydrologic budget
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 83
終了ページ 88
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313829
JaLCDOI 10.18926/fest/11501
フルテキストURL 010_075_081.pdf
著者 Kankam-Yeboah Kwabena| Asare Enoch B.| Gyau-Boakye Philip| 西垣 誠|
抄録 The rapid impact assessment (RIAM), which was developed in Denmark, is a new tool for the execution of environmental impact assessments. RIAM is quite flexible, transparent and leaves a permanent record, which can be independently checked, validated or updated. RIAM has successfully been used to prioritize water resources management problems in Ghana in the order of which problems call for the most urgent attention. The priority list was easily validated and accepted to be the true reflection of the situation at a national workshop in which experts and representatives from water agencies, donor agencies, university faculties and departments, research institutes, private institutions and organizations including Non Governmental Organizations (NGOs) participated. The study has shown that RIAM, which can also be used in a developing country like Ghana, is a very useful tool in such prioritization process as has been applied in this exercise.
キーワード Water resources management problems prioritization impact indicators RIAM river basins Ghana
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 75
終了ページ 81
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313917
JaLCDOI 10.18926/fest/11500
フルテキストURL 008_039_052.pdf
著者 Kankam-Yeboah Kwabena| Dapaah-Siakwan Stephen| 西垣 誠| 小松 満|
抄録 Increasing human population, changing lifestyles and environmental considerations have resulted in increased utilization of groundwater resources worldwide. Thus, in turn, has led to the decline of groundwater levels in some countries and Ghana is no exception to this problem. To augment the availability of groundwater resources for various uses, numerous techniques have been developed in many part of the world, one of which is the construction of underground dams. The successful construction and utilization of underground dams, however, depends very much on the physical and hydrogeological conditions at the dam sites. Ghana is underlain by Precambrian crystalline igneous and metamorphic rocks ; and Paleozoic consolidated sedimentary formations. There are further subdivided and described locally as the Birimian, Dahomeyan, Buem, Togo Series, Tarkwaian, Granites, Voltain, Coastal Block Fault, Coastal Plain and Quaternary Alluvium. The review of these and the pre-requisite conditions necessary for the construction of underground dams indicate that underground dams could be constructed and utilized in some parts of Ghana, especially where the overburden is shallow, in the Dahomeyan granites and in the recent formations consisting of alluvial and coastal sands and gravels. This paper is part of a continuing research programme being carried out by the authors.
キーワード hydrogeology geology underground dam sand-storage dam sub-surface dam water supply
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 39
終了ページ 52
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313713
JaLCDOI 10.18926/fest/11499
フルテキストURL 010_067_074.pdf
著者 Dewan Ashraf M.| Alam Md. Mahabubul| 西垣 誠|
抄録 The objective of this paper is to delineate flood prone areas and estimate damage in Greater Dhaka during the 1998 catastrophic flood using an integrated approach of GIS and remote sensing. Time series RADARSAT SAR data is acquired and used to demarcate flood boundaries for the 1998 flood event. This was accomplished by thresholding linear SAR imageries. Flood estimation demonstrated that flood areas steadily increased from early July 1998 and peaked on 25 August 1998 inundating 53% lands due to heavy monsoonal downpour and discharge from upstream points. Different thematic layers were combined with a derived flood map in order to assess flood damage for the same event. Flood damage analysis revealed that substantial damage has occurred in Greater Dhaka during the 1998 flood.
キーワード Synthetic Aperture Radar (SAR) flood delineation 1998 flood flood damage Greater Dhaka
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 67
終了ページ 74
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313624
JaLCDOI 10.18926/fest/11498
フルテキストURL 008_027_038.pdf
著者 Zou Dagang| 阿部 宏史|
抄録 China has achieved a remarkable economic growth in the past two decades. However, the rapid economic development has led to regional disparities between the advanced coastal regions and the other regions. Regional development planning in China has sought to achieve the redress of regional disparities as well as a high economic growth. This paper aims to examine the role of core cities in the development of Chinese regional economy and their impact on regional differentials. Following a brief review of regional development planning in China, the paper examines the role of core cities on the regional development and the trends in regional disparities using data for seven coastal provinces (Guangdong, Fujian, Zhejiang, Jiangsu, Shandong, Hebei and Liaoning) and three municipalities (Beijing, Tianjin and Shanghai) in the period 1989-1997. It shows that while the coastal regions achieved a high economic growth, the extent of regional disparities and the contributions of core cities to the reduction of economic differentials varied among provinces. The paper concludes by proposing future issues on regional development planning in China.
キーワード regional disparities core cities per capita GDP lavor productivity per capita employment
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 27
終了ページ 38
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313409
JaLCDOI 10.18926/fest/11497
フルテキストURL 008_023_026.pdf
著者 渡辺 雅二| Numaguchi Satoshi|
抄録 The global positioning system (GPS) is utilized for analysis of flows in the water environment. A float equipped with a GPS unit is designed to drift on the surface of the water. Its driving force is the fluid resistance exerted on a pair of rectangular plates. While it travels over the surface, the GPS unit evaluates its position every second, and spatiotemporal data that specify its motion are transmitted to be recorded. Results of experiments conducted to study unsteady flows generated in Kojima Lake are introduced.
キーワード water environment global positioning system
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 23
終了ページ 26
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313912
JaLCDOI 10.18926/fest/11496
フルテキストURL 010_057_065.pdf
著者 Dewan Ashraf M.| Alam Md. Mahabubul| 西垣 誠|
抄録 This paper is an attempt to develop a series of maps that precisely depict flood prone areas in Greater Dhaka, Bangladesh using remote sensing techniques. Multi-temporal RADARSAT SAR data were acquired and employed to delineate open water flood boundary during the floods of 1998 and 2000. Using a threshold algorithm, SAR data is segregated into water and non-water areas. The empirical threshold value was obtained by using visual interpretation technique, local knowledge of the study site and by deriving corresponding pixel values to land/water from each image. The result demonstrated that 53 percent of the study area was heavily inundated in 1998 flood which is the largest submerged area during a catastrophic scenario. In contrast, 35.32 percent area was flooded during the year 2000 which represents the area under water for a normal event. Using the reference data acquired from field visit, derived flood maps were further validated. Moderate accuracy is obtained for all flood maps, however, July 1998 image attained the highest overall accuracy (86%) in the dataset. The derived flood maps are expected to be useful to mitigate losses of lives and property from river water flooding in Greater Dhaka. Furthermore, this information would be worthwhile to develop an efficient flood disaster management system.
キーワード SAR open water flood 1998 and 2000 floods Greater Dhaka RADARSAT
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 57
終了ページ 65
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313953
JaLCDOI 10.18926/fest/11495
タイトル(別表記) A note on the effect of quadratic term on final pattern in Turing model
フルテキストURL 008_019_022.pdf
著者 山内 憲一| 梶原 毅|
抄録 The effect of the quadratic term on the final pattern in Turing model is disscussed numerically. Turing models are non linear reaction diffusion equations. Linear analysis for wave length is very useful to find evolving waves. But when a quadratic term appear in the equation, an initial wave can disappears and changes drastically to a spot which is independent of linear analysis.
キーワード Turing instability Reaction Diffusion equation Quadratic term
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 19
終了ページ 22
ISSN 1341-9099
言語 日本語
論文のバージョン publisher
NAID 120002313586
著者 宗 淳一|
発行日 2007-03-23
出版物タイトル
資料タイプ 学位論文
JaLCDOI 10.18926/fest/11492
タイトル(別表記) Development of a statistical survey analysis system using Internet
フルテキストURL 008_009_017.pdf
著者 藤野 友和| 垂水 共之|
抄録 We constructed the online analysis system of the Okayama Activity Area Survey in place since 1979. This is one way to solve the problem in case of releasing the result of a statistical survey. In this paper, we treat the detail of the structure of the system.
キーワード microdata statistical disclosure control web based system online database
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 9
終了ページ 17
ISSN 1341-9099
言語 日本語
論文のバージョン publisher
NAID 120002314053
著者 藤本 剛|
発行日 2007-03-23
出版物タイトル
資料タイプ 学位論文
著者 末丸 俊二|
発行日 2007-03-23
出版物タイトル
資料タイプ 学位論文
JaLCDOI 10.18926/fest/11489
タイトル(別表記) Considering variable selection criteria in correspondence analysis
フルテキストURL 010_049_056.pdf
著者 森 裕一| 杜 暁東| 飯塚 誠也|
抄録 Ordinary goodness of fit criteria in correspondence analysis are considered as variable selection criteria in case correspondence analysis which is one of multivariate methods without external variables can be applied. The goodness of fit criteria focused here are proportion of cumulative eigenvalues, proportion of cumulative squared-eigenvalues and proportion of cumulative off-diagonal fitness. Each criterion is applied to a couple of real data sets and evaluated with interpretation of the selection process and result (selected subset of variables). Four selection procedures such as backward elimination and forward-backward selection are also performed to compare with each other as well as with all possible selection procedure. These results illustrate that the criteria can be used as selection criteria to select a subset of variables in correspondence analysis and to assess categorical items (questions) in a survey (questionnaire).
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 49
終了ページ 56
ISSN 1341-9099
言語 日本語
論文のバージョン publisher
NAID 120002313834
著者 小山 文彦|
発行日 2007-03-23
出版物タイトル
資料タイプ 学位論文
JaLCDOI 10.18926/fest/11487
フルテキストURL 008_001_007.pdf
著者 Tsunekuni Yasuhiro| Ohga Yukio| 石川 洋文|
抄録 In 1990s, there were rapid increases in the number of HIV epidemics and AIDS cases in Thailand, Southeast Asia. In particular the risk of HIV infection was very high among female prostitutes who played a large part in the transmission of HIV infection. We formulated a mathematical model for the transmission of HIV in prostitutes. We carried out the model simulations to analyze the incipient spread of HIV infection and the effect of AIDS prevention methods in prostitutes. The simulation of our model indicates that even if the effect of AIDS prevention methods such as the recommendation of condom use for commercial sex workers would block the transmission at rate by 70%, the elimination of the HIV epidemic is still beyond attainment.
キーワード AIDS HIV prostitution Thailand transmission model
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2003-03
8巻
1号
開始ページ 1
終了ページ 7
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002314019
JaLCDOI 10.18926/fest/11486
タイトル(別表記) Variable Selection Method using Apriori Algorithm on Contingency Table
フルテキストURL 010_041_047.pdf
著者 大野 学| 垂水 共之|
抄録 We proposed a new applied method for induction of variable selection on contingency table. This method is the application of Apriori algorithm on variable selection of contigency table with iteraction. We assume that variables are dichotomous variable. We confirm that can be select variable, when minimun support is low level by using AIC on variable selection criterion.
キーワード Apriori Algorithm Varable Selection Contigency Table Interaction
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 41
終了ページ 47
ISSN 1341-9099
言語 日本語
論文のバージョン publisher
NAID 120002313938
JaLCDOI 10.18926/fest/11485
フルテキストURL 010_029_039.pdf
著者 Ju Xian Meng|
抄録 The generalized Grothendieck-Witt ring of nonsingular Hermitian forms with positioning map is the cartesian product of the ordinary Grothendieck-Witt ring of nonsingular Hermitian forms and a map ring. We study the generalized Grothendieck-Witt ring by computing the map ring.
キーワード Grothendieck Witt ring orbit GAP
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 29
終了ページ 39
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313655
JaLCDOI 10.18926/fest/11484
フルテキストURL 010_023_028.pdf
著者 渡辺 雅二| Liu Ying| Wang Ming Jun|
抄録 Topographical data of Kojima Lake have been updated by applying data obtained after dredging. Together with tide level of Kojima Bay and water levels of Kurashiki River and Sasagase river, the information was incorporated in computational analysis of unsteady flows generated in the lake when the water was discharged from Kojima Lake to Kojima, Bay. A finite element method was applied to equations governing unsteady flows, and the transition of discharge was obtained.
キーワード water environment finite element method numerical simulation
出版物タイトル 岡山大学環境理工学部研究報告
発行日 2005-02-28
10巻
1号
開始ページ 23
終了ページ 28
ISSN 1341-9099
言語 英語
論文のバージョン publisher
NAID 120002313649