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JaLCDOI 10.18926/fest/11571
FullText URL 005_081_098.pdf
Author Magda Waldemar| Maeno, Shiro| Nago, Hiroshi|
Abstract A dynamic response of a submarine pipeline buried in sandy seabed sediments to water loading generated by harmonically oscillating water-table vertical movements is examined in the present report experimentally and numerically. The aim of small-scale laboratory experiments was: (1) to record time-histories of pipeline vertical displacements, and (2) to observe a shape of slip surface of an overburden sand body involved in breakout together with the pipeline. A parametric study was carried out in order to investigate the influence of two meaningful factors, that is the depth of burial and the specific gravity of pipeline, on a gradual upward displacement of the pipeline. Based on a numerical finite-element 2D-analysis of the hydrodynamic pore pressure and effective stresses oscillations in the pipeline vicinity, an analysis of the pipeline stability potential is presented, in which all the experimental cases tested are verified. All important component forces (e.g., hydrodynamic uplift force) associated with floatation phenomenon of the buried submarine pipeline are considered and quantified.
Keywords submarine pipeline surface waves pore pressure floatation stability
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 81
End Page 98
ISSN 1341-9099
language English
File Version publisher
NAID 120002313700
JaLCDOI 10.18926/fest/11570
FullText URL 003_105_120.pdf
Author Kidtimonton Surasri| Mitsuno, Toru|
Abstract Two optimization models are formulated based on different objectives for assisting the irrigation planner in making decision on agricultural planning during drought year. The sensitive degree of water shortage area in the irrigation project are classified by those models. They are solved by simplex method. Firstly, the Two-phase method is applied to analyze the artificial variables in the formulated model. Then, the formulated model is modified after getting rid of the artificial variables to obtain the feasible solution. The agricultural planning is planned by considering the classified area with social equity and economic improvement. Crop diversification is introduced to conduct in the very sensitive water shortage area and intermittent irrigation system is introduced to operate in the moderately sensitive water shortage area. The integrated farming system, the separation of land owner and cultivator and the disposition of substitute lots system are also suggested to conduct in this study project.
Keywords agricultural planning Two-phase method integrated farming sensitive water shortage disposition of substitute lots system
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 105
End Page 120
ISSN 1341-9099
language English
File Version publisher
NAID 120002313819
JaLCDOI 10.18926/fest/11569
FullText URL 005_071_079.pdf
Author Jafar Ali Mohammad| Takeshita, Yuji| Fujii, Hiroaki|
Abstract In-situ determination of fundamental hydraulic parameters like variably saturated hydraulic conductivity (K(FS)) and the matric flux potential (Φ(m)) provides a foundation from which several other unsaturated soil parameters can be estimated, namely the Alpha (α*) parameter. This Alpha parameter is the one of the components of 3D unsaturated flow in vadose zone and its value is the measure of the capillary component of unsaturated flow pattern. Here an in-situ technique, Pressure Infiltrometer is introduced to record the steady flow rate applying a constant positive head on an unsaturated soil surface. The aim of this paper is to check the shape factor of 3D flow geometry and to find out its sensitivity on other unsaturated hydraulic parameters and to find out the influence of Alpha parameters on the results of the in-situ estimation of field-saturated hydraulic conductivity.
Keywords Field-saturated hydraulic conductivity Matric flux potential Alpha parameter Shape factor In-situ test
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 71
End Page 79
ISSN 1341-9099
language English
File Version publisher
NAID 120002313869
JaLCDOI 10.18926/fest/11568
FullText URL 003_097_104.pdf
Author Hassan Muhammad Qumrul| Okubo, Kenji|
Abstract Surface air temperature distribution over the Ganges Delta Region of southwest Bangladesh and its tendency of warming are discussed through the analyses based upon the long-term temperature data from 1900-93. The data consist of two parts corresponding to the time-periods: 1973-93 and 1900-72. The study area is one of most affected places by the annual monsoon hydrological cycle and the present observation from these temperature data indicate that the surface air temperature gradient in the north-south direction is significant in the rainy season and that the temperature of the region is at an increasing tendency; the warming rate during the data periods (1900-93) on the long-term mean annual basis is estimated as 0.77℃ at Satkhira of the Khulna division and 0.29℃ as an areal average including the Barisal division, for the time difference of about half a century between the data periods before and after 1972.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 97
End Page 104
ISSN 1341-9099
language English
File Version publisher
NAID 120002313675
JaLCDOI 10.18926/fest/11567
FullText URL 003_075_095.pdf
Author Magda Waldemar| Maeno, Shiro| Nago, Hiroshi|
Abstract The response on sandy seabed sediments to a harmonically oscillating water-table, with a special consideration of the wave-induced pore-pressure oscillations around a pipeline buried in seabed sediments, is studied in the present work experimentally and numerically. The aim of the analysis was: (1) to observe a true distribution pattern of the wave-induced pore-pressure oscillations acting on the pipeline outer surface, and (2) to verify small-scale test results using numerical computations performed for a wide range of saturation conditions of seabed sediments, under the assumption of a compressible two-phase medium compound of the pore-fluid and soil skeleton, as well as a finite thickness of a permeable seabed layer.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 75
End Page 95
ISSN 1341-9099
language English
File Version publisher
NAID 120002313821
JaLCDOI 10.18926/fest/11566
FullText URL 005_057_069.pdf
Author Fujita, Ryousuke|
Abstract Let G be a finite group, Y a finite connected G-CW-complex, and let Ⅱ(Y) denote G-poset (in the sense of Oliver-Petrie) associated to Y. They defined the abelian group Ω(G,Ⅱ(Y)) consisting of all equivalent classes of Ⅱ(Y)-complexes. They also defined the subgroup Φ(G,Ⅱ(Y)) related to Ⅱ(Y)-resolutions. We call Φ(G,Ⅱ(Y)) the resolution module of Y. Applying the Oliver-Petrie theory to the universal covering space Y, we obtain the group Ω(G,Ⅱ(Y)), where G is a certain extension of G by π(1)(Y). Then the canonical homomorphism ν : Ω(G,Ⅱ(Y))→ Ω(G,Ⅱ(Y)) induced by the projection Y → Y is an isomorphism. In this paper, for G = Z(p)×Z(q) we construct a finite G-CW-complex Y such that π(1)(Y) Zq and ν(Φ(G,Ⅱ(Y)) ≠ Φ(G,Ⅱ(Y)), where p and q are arbitrary distinct primes.
Keywords G-CW-complex G-map G-poset
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 57
End Page 69
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313951
JaLCDOI 10.18926/fest/11565
Title Alternative An Analysis on the Structure of Evaluating Street Landscape Through Semantic Differential Technique
FullText URL 003_063_074.pdf
Author Inouye, Hiroshi| Fujii, Makiko|
Abstract The structure on the evaluation of street landscape by men is analyzed through semantic differential technique. Some characteristic streets in Okayama and Kurashiki cities are selected for the analysis and they are evaluated by many subjects using their photographs. The results are outlined on their profile curves. Then, they are analyzed through factor analysis and some communal factors are induced. It is explained what these communal factors mean. Finally, it is considered how to make beautiful and comfortable street landscape.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 63
End Page 74
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313379
JaLCDOI 10.18926/fest/11564
FullText URL 005_047_056.pdf
Author Otake, Masanori| Ohtsubo, Ryusuke| Tomita, Makoto| Tanaka, Yutaka|
Abstract Main content of this paper is to classify IQ individuals into two categories of normal and abnormal groups. It is too difficult to divide IQ individuals into two groups of normal IQ group and abnormal group because of sparse number of cases with mental retardation. Therefore, we examined a normality of 1673 IQ individuals, but a significant difference was noted for the IQ data. The lowest three mentally retarded cases of less than or equal to 59 IQ score were excluded, the IQ data then fitted to a normal distribution well. The critical value which minimizes the probability of classification is obtained on the basis on an approximate technique with regard to normality. An approximate probability of misclassification for individuals at random from mixture of two normal populations is 25.5%.
Keywords Compound distribution normality Prenatal exposure IQ misclassification
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 47
End Page 56
ISSN 1341-9099
language English
File Version publisher
NAID 120002313674
JaLCDOI 10.18926/fest/11563
FullText URL 003_047_062.pdf
Author Otake, Masanori| Tanaka, Yutaka| Lee Sunghee|
Abstract Exposure to ionizing radiation has been testified to have harmful effects on the developing human brain, particularly in the highly vulnerable period of 8-15 weeks after ovulation as an incereased frequency of severe mental retardation. However, the distribution of cases of severe mental retardation suggests a threshold in the low dose region. Data are composed of a binary (1,0) for mentally retarded or normal individuals. The statistical approaches with a threshold are conceivable for a simple, odds, logistic and Gompertz regression models. Estimation of threshold and 100(1-α)% confidence limits are derived from the maximum likelihood technique based on a profile approach.
Keywords mental retardation threshold model prenatal exposure profile approach atomic bombings
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 47
End Page 62
ISSN 1341-9099
language English
File Version publisher
NAID 120002313935
JaLCDOI 10.18926/fest/11562
FullText URL 003_037_046.pdf
Author Kim Hyum-Jeong| Tarumi, Tomoyuki| Tanaka, Yutaka|
Abstract The present paper deals with multivariate analyses applied to the maximum likelihood estimate(s) for (the mean vector and) the covariance matrix based on incomplete data, and derives influence functions for the mean vector, the covariance matrix and some statistics in multivariate analyses. Influential directions in the sense of Cook's local influence are also derived. A numerical example is given to show the usefulness of the proposed method.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 37
End Page 46
ISSN 1341-9099
language English
File Version publisher
NAID 120002313576
JaLCDOI 10.18926/fest/11561
FullText URL 005_035_046.pdf
Author Choi, Seung Bae| Tanaka, Yutaka|
Abstract Spatial data is analyzed in three stages of 1) estimating the variograms, 2) fitting a model for the estimated variograms and 3) predicting the value at unknown location based on the information at known locations (kriging). Recently, it has become a subject of interest to detect influential observations in these stages. Choi and Tanaka(1999) have derived influence functions in the above three stages and have proposed sensitivity analysis procedure. So far influence functions have only been derived for variograms by Gunst and Hartfield(1996). The present article makes a comparison of the performances between those influence functions for variograms derived by Choi and Tanaka(1999) and by Gunst and Hartfield(1996). A real numerical example is given to discuss the validity or usefulness of those influence functions.
Keywords Stationary spatal data Influence function Sample variogram Median-polish residual
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 35
End Page 46
ISSN 1341-9099
language English
File Version publisher
NAID 120002313332
JaLCDOI 10.18926/fest/11560
FullText URL 003_031_036.pdf
Author Sasaki, Toru| Kajiwara, Tsuyoshi| Ishikawa, Hirofumi|
Abstract We have computed the phase of spreading contaminations in Kojima Lake by using the upwind-type finite element method. We have treated the two cases: the pollutant flows from the Sasagase river and from the Kurashiki River. We see that the upwind-type finite element method is effective in both cases, when the diffusion constant is quite small.
Keywords Upwind-type Finite element method Kojima Lake
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 31
End Page 36
ISSN 1341-9099
language English
File Version publisher
NAID 120002313715
JaLCDOI 10.18926/fest/11559
FullText URL 005_031_034.pdf
Author Watanabe, Masaji|
Abstract We study unsteady flow that models lake flow in Kojima Lake. We assume that a lake is connected to another area with gates, and that those gates are opened when the water level outside the gates is lower than the water level of the lake. We study unsteady flow due to the opening of the gates. We analyze the problem with the finite element method, and take detailed structures of the gates into account.
Keywords unsteady flow lake flow finite element method
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 31
End Page 34
ISSN 1341-9099
language English
File Version publisher
NAID 120002313848
JaLCDOI 10.18926/fest/11558
FullText URL 003_025_029.pdf
Author Kajiwara, Tsuyoshi|
Abstract In this paper, we define coaction crossed product of Hilbert C*-bimodule by finite groups. We show that resulting bimodule is of finite type, and compute indices of them. We present a Takesaki-Takai duality theorem which is some non-commutative generalization of abelian groups case in [KW2].
Keywords Hilbert bimodule Coaction Crossed product
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 25
End Page 29
ISSN 1341-9099
language English
File Version publisher
NAID 120002313716
JaLCDOI 10.18926/fest/11557
Title Alternative Mathematical analysis of virus infectious diseases by ordinary differential equations
FullText URL 005_023_030.pdf
Author Sasaki, Toru| Kajiwara, Tsuyoshi|
Abstract Some mathematical models describing interaction of virus and cells in vivo are reviewed. Similar models using systems of ordinary differential equations can be used for the analysis of dynamics of virus and cells for different kinds of virus. Models for human immunodeficiency virus, hepatitis C virus and hepatitis B virus are treated here. Although models are similar, different approximations can reduce the systems to the explicitly solvable forms. The solutions obtained here can be used to estimate biological parameters.
Keywords Virus Mathematica models HIV HCV HBV
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 23
End Page 30
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313498
JaLCDOI 10.18926/fest/11556
FullText URL 003_011_024.pdf
Author Watanabe, Masaji|
Abstract We study a system that models a problem in which an oscillatory unit is coupled to a passive medium. We analyze the case in which an RCL circuit is coupled to an RC circuit. Some numerical results indicate when slow oscillations occur in coupled systems.
Keywords coupled circuits Van der Pol's equation slow oscillations
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 11
End Page 24
ISSN 1341-9099
language English
File Version publisher
NAID 120002313697
JaLCDOI 10.18926/fest/11555
Title Alternative Simulations of Heel Impact by Viscoelastic Models
FullText URL 005_013_021.pdf
Author Kokubo, Masahito| Sasaki, Toru|
Abstract The purpose of this study is to make some body models with viscoelastic model, to simulate the heel impact and to obtain the ground reaction force. In this paper, we build up body models of linear viscoelastic elements and mass elements to simulate heel impact. Here we consider the systems of linear differential equations numerically for the preparation of mathematical analysis in future. The simplest model with two mass elements is hardly able to simulate the heel impact if the rate of mass of elements is realistic. The models with more elements are suitable to simulate for actual rate of weight of body segments. The model with three mass elements makes it possible to guess the force to each body segment.
Keywords Running Heel Impact Viscoelastic Model Biomechanics
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 13
End Page 21
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313531
JaLCDOI 10.18926/fest/11554
FullText URL 003_005_009.pdf
Author Ishikawa, Hirofumi|
Abstract We investigate the Maass wave form for Γ(0)(2) whose eigenvalue of Laplacian Δ is 1/4-π(2)/log(2)(√2-1). In this note, we study the methods of calculation of its Fourier coefficients and carry out the numerical calculations.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 5
End Page 9
ISSN 1341-9099
language English
File Version publisher
NAID 120002313535
JaLCDOI 10.18926/fest/11553
Title Alternative Mathematical analysis of pathogenesis of viral hepatitis.
FullText URL 005_007_011.pdf
Author Sasaki, Toru| Kajiwara, Tsuyoshi|
Abstract Simple mathematical models are considered to explain the pathogenesis of viral hepatitis. Dynamics of populations of liver cells and two virus strains are analyzed qualitatively. This analysis suggests the possibility that the viral mutation causes the hepatitis from the state of carrier.
Keywords hepatitis mathematical model mutation
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 7
End Page 11
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313400
JaLCDOI 10.18926/fest/11552
FullText URL 003_001_003.pdf
Author Nakajima, Atsushi|
Abstract The existence of a derivation in a near-ring is not known. We construct derivations on 2×2 matrix near-ring in the sense of [MW].
Keywords Near-ring matrix near-ring derivation
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 1
End Page 3
ISSN 1341-9099
language Japanese
File Version publisher
NAID 120002313635