検索結果 7815 件
| 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 巻 | 10巻 |
| 号 | 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 巻 | 10巻 |
| 号 | 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 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 |
| 巻 | 10巻 |
| 号 | 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 |
| 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 |
| 巻 | 8巻 |
| 号 | 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 |
| 巻 | 10巻 |
| 号 | 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 |
| 巻 | 10巻 |
| 号 | 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 |
| 巻 | 10巻 |
| 号 | 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 |
| JaLCDOI | 10.18926/fest/11483 |
|---|---|
| タイトル（別表記） | On Persistence in Dynamical Systems (Review) |
| フルテキストURL | 010_013_021.pdf |
| 著者 | 佐々木 徹| 梶原 毅| |
| 抄録 | Some important results on persistence are reviewed. These results concern the behavior of the orbits approaching the boundary. The orbits restrict the flow on the boundary, if one of them approaches more than one invariant set. A typical example is a model for cyclic competition, where the heteroclinic cycle can be the ω-limit set. Thus the persistence can be reduced to some conditions on the boundary flow. |
| キーワード | persistence ordinary differential equation dynamical 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 | 2005-02-28 |
| 巻 | 10巻 |
| 号 | 1号 |
| 開始ページ | 13 |
| 終了ページ | 21 |
| ISSN | 1341-9099 |
| 言語 | 日本語 |
| 論文のバージョン | publisher |
| NAID | 120002313932 |
| JaLCDOI | 10.18926/fest/11482 |
|---|---|
| フルテキストURL | 011_093_097.pdf |
| 著者 | 木村 邦生| 山崎 慎一| Cassidy Patrick E.| Fitch John W| Venumbaka Sreenu R.| |
| 抄録 | Fluorine-containing poly(ether ketone)s was synthesized by the nucleophilic aromatic substitution reaction of 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane and 4,4'-bis(2,3,4,5,6-pentafluorobenzoyl) diphenyl ether in super-critical CO(2). Polymerizations were carried out at 80℃ for 6 hours under 5000 psi of CO(2) pressure, which was super-critical phase. Polymerization concentration was 0.5 g of polymer in 10 - 12 mL of CO(2). The polymer was not obtained in CO(2) due to the insolubility of both the potassium bisphenoxide and the polymer into CO(2). However, the polymer was formed by an addition of DMAc and NMP in CO(2), even though molecular weight was not so high. Very small amount of co-solvents which were immiscible with CO(2) was effective, and it was 1/20 - 1/25 amount of the solvent used in the conventional poly(ether ketone) synthesis. The polymerization mechanism was also discussed. |
| キーワード | super-critical carbon dioxide plastics high performance environmentally benign |
| 出版物タイトル | 岡山大学環境理工学部研究報告 |
| 発行日 | 2006-03-15 |
| 巻 | 11巻 |
| 号 | 1号 |
| 開始ページ | 93 |
| 終了ページ | 97 |
| ISSN | 1341-9099 |
| 言語 | 英語 |
| 論文のバージョン | publisher |
| NAID | 120002313564 |
| JaLCDOI | 10.18926/fest/11481 |
|---|---|
| フルテキストURL | 010_009_011.pdf |
| 著者 | 梶原 毅| 佐々木 徹| |
| 抄録 | An elementary proof of permanence for a simple mathematical model proposed by Nowak and Bangham. In many papers, permanence property is proved by theorems established by the general theory of dynamical system. In this paper, we present an elementary proof only using differential inequalities and the theory of linear differential equations with constant coefficients. |
| キーワード | Permanence dynamical system pathogen |
| 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 |
| 巻 | 10巻 |
| 号 | 1号 |
| 開始ページ | 9 |
| 終了ページ | 11 |
| ISSN | 1341-9099 |
| 言語 | 英語 |
| 論文のバージョン | publisher |
| NAID | 120002313596 |
| JaLCDOI | 10.18926/fest/11480 |
|---|---|
| タイトル（別表記） | A Case Study on How to Teach English at University Adopting TOEIC (2) -Evaluation after three years- |
| フルテキストURL | 009_167_178.pdf |
| 著者 | 諸川 重剛| 荻野 勝| 神﨑 謙一| |
| 抄録 | Three years ago, we wrote an essay about our new English-teaching program that adopted TOEIC. We gave out questionnaires to the students with questions ranging from what they thought of English in general to what they thought of our new program. In the essay, we discussed some of the results. Even though students' response was relatively positive in this initial survey, we wrote in our conclusion that we would like to renew and reform our classes. Receiving feedback from students periodically would help us improve their English ability. In order to see the change of students' attitude toward English and also toward our program, we conducted the same research last February. This time the results were not as favorable. For example, the number of students who thought their English ability was poor increased and those who showed a positive attitude toward our program decreased. We discussed and wrote what we learned from those results. We raised the question whether there was a gap between what we tried to teach to the students and what they wanted from us. Possible reasons were discussed on why we could not succeed in stimulating the students into studying English further. In April 2003 Okayama University started a new English curriculum, in which the classes for proficiency tests including TOEIC were opened. Similar classes have been set at many other universities. This survey will be a help to the further development of English education adopting TOEIC. |
| キーワード | TESOL TOEIC questionnaires team teaching |
| 出版物タイトル | 岡山大学環境理工学部研究報告 |
| 発行日 | 2004-02-27 |
| 巻 | 9巻 |
| 号 | 1号 |
| 開始ページ | 167 |
| 終了ページ | 178 |
| ISSN | 1341-9099 |
| 言語 | 日本語 |
| 論文のバージョン | publisher |
| NAID | 120002313460 |
| JaLCDOI | 10.18926/fest/11479 |
|---|---|
| フルテキストURL | 010_001_007.pdf |
| 著者 | Wang Xiao Dong| 石川 洋文| |
| 抄録 | The one-way hash function plays an important role in digital signatures and message authentication from the viewpoint of security. No effective attacking method has been discovered to the algorithm of hash function standard. In this study, we tried to attack SHA-256 in encryption mode using linear and differential cryptanalysis to solve a private key. We deduced that an estimate of the private key would require huge known and chosen plaintexts in both linear and differential cryptanalysis, and that it would be difficult to decipher SHA-256 in view of the required computation. |
| キーワード | differential cryptanalysis encryption mode hash function linear cryptanalysis SHA-256 |
| 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 |
| 巻 | 10巻 |
| 号 | 1号 |
| 開始ページ | 1 |
| 終了ページ | 7 |
| ISSN | 1341-9099 |
| 言語 | 日本語 |
| 論文のバージョン | publisher |
| NAID | 120002313630 |
| JaLCDOI | 10.18926/fest/11478 |
|---|---|
| フルテキストURL | 009_163_166.pdf |
| 著者 | Nakatsu Shogo| 坪井 貞夫| |
| 抄録 | Diels-Alder reactions of 5,5,5-trichloro-3-penten-2-one and ethyl 4,4,4-trichloro-2-butenoate with cyclopentadiene in the presence of a chiral Lewis acid gave exo-2-acetyl-endo-3-trichloromethyl-bicyclo[2.2.1]hept-5-ene and exo-2-ethoxycarbonyl-endo-3-trichloromethylbicyclo[2.2.1]hept-5-ene with 40% and 7% e.e., respectively. |
| キーワード | asymmetric reaction Diels-Alder reaction asymmetric Diels-Alder reaction chiral Lewis acid trichloromethy group |
| 出版物タイトル | 岡山大学環境理工学部研究報告 |
| 発行日 | 2004-02-27 |
| 巻 | 9巻 |
| 号 | 1号 |
| 開始ページ | 163 |
| 終了ページ | 166 |
| ISSN | 1341-9099 |
| 言語 | 英語 |
| 論文のバージョン | publisher |
| NAID | 120002313377 |
| JaLCDOI | 10.18926/fest/11477 |
|---|---|
| タイトル（別表記） | Efficient Chain Extension Reaction of Poly (butylene terephthalate) by using Crystallization |
| フルテキストURL | 012_167_171.pdf |
| 著者 | 井原 誠司| 城間 弥| 山崎 慎一| 木村 邦生| |
| 抄録 | Plastics are quite important materials for not only industrial usages but also our daily life. Many plastics are difficult to reuse because they are susceptible to UV, hydrolysis and so on leading to the reduction of molecular weight. Among them, poly (butylenes terephthalate) (PBT) is a valuable materials prepared by polycondensation reaction, and PBT has the same limitation to reuse. Hence, efficient chain extension reaction for recovered PBT has been needed to improve the properties damaged by chain scission. In this study, new chain extension reaction had been examined by using crystallization as pre-treatment. Isothermal crystallization at 161℃ concentrated the chain end-groups on the surface of the crystals, and chain extension reaction at 210℃, which was lower than the melting temperature of PBT, enhanced the molecular weight significantly compared with the reaction over the melting temperature. It concluded that the pre-treatment of crystallization was favorable for the efficient chain extension reaction and this result provided the new technology for the effective reuse of the plastics. |
| キーワード | Polyester material recycle crystallization chain extension reaction |
| 出版物タイトル | 岡山大学環境理工学部研究報告 |
| 発行日 | 2007-03-15 |
| 巻 | 12巻 |
| 号 | 1号 |
| 開始ページ | 167 |
| 終了ページ | 171 |
| ISSN | 1341-9099 |
| 言語 | 日本語 |
| 論文のバージョン | publisher |
| NAID | 120002314029 |