In the mathematical system design division, the strength, instability and deformation properties of materials and structures are studied based on numerical analysis, experiment, and mathematical theory. Materials under consideration are quite extensive, including: steel, sand, soil, concrete and rock, with an emphasis on the viewpoint of bifurcation. Structures considered are shells and domes, and so on. The investigation of the mechanism of a failure mode, for example, is a typical topic in our division. It is the fundamental strategy to describe the qualitative aspects of deformations of materials by bifurcation theory, while observe their quantitative aspects by experiments and numerical analyses. Bifurcation bevior is so ubiquitous that it can potentially govern the formation of shear bands of materials, the mechanism of material failure and softeing, spatial pattern of faults, and so on.
Graduation Theses
- 2015
- Bifurcation induced agglomeration in a racetrack economy: Dependence on a number of cities
- Spatial frequency analysis of one-dimensional economic agglomeration patterns
- Influence of anisotropy on 3D bifurcation and localization behavior on cubic sand specimen
- A re-formulation of extended subloading surface model for cyclic plasticity within small strain framework: hyperelastic-based formulation and fully implicit return mapping scheme
- 2014
- Analysis of population distribution in the East Coast of US using Core-Periphery model
- Spatial frequency analysis of economic agglomeration patterns based on bifurcation mechanism
- Strength degradation and member damage of transmission towers caused by foundation displacement
- Bearing capacity analysis of foundation of transmission tower on the slope crest
- 2013
- Agglomeration of a core-periphery model on a square lattice
- Attempt to develop eddy current technology for through-deck cracks in steel orthotropic decks
- Bifurcation and imperfection sensitivity as an underlying mechanism of strength variation due to material ununiformity in sand specimen
- 2012
- Classification of bifurcation points and tracing of branching solutions for two-dimensional agglomeration pattern
- Computational study on shear lag effect in a corner of steel bridge bent during earthquakes
- Evaluation of sensitivity of mechanical factors of dental implants
- 2011
- Study of bifurcation mechanism for a two-dimensional pattern formation of population distribution
- Analysis of agglomeration behavior of a system of cities on a line segment
- Effect of support movements on ultimate strength of tension and suspension towers for electric power transmission
- Study of insertion direction of dental implants by FEM analysis considering heterogeneity of mandibular bone
- 2010
- Self-orgnization of Losch's hexagonal market areas for a two-dimensional system of cities
- Study on population agglomeration and market area formation of a system of cities on a straight line
- Evaluation of ultimate behavior of transmission towers with different sizes subjected to unequal support movement
- pullout capacity analysis of anchors of transmission towers embedded in a ground close to slopes
- A fundamental study on mechanical behavior of dental implants
- 2009
- Analysis of agglomeration patterns of a system of cities on a 2D square grid
- Evaluatioin of elast-plastic buckling strength of transmission tower subject to support movement
- 2008
- Study of insersion direction of dental implants by FEM anlaysis
- Evaluation of buckling strength of a truss bridge due to live load variation based on initial imperfection sensitivity law
- Effect of the footing displacement and soil deformation on the residual strength of transmission tower
- Study of history dependence of spatial distribution of population on transportation cost parameters
- 2007
- Finite element analysis of mechanical stress in oral implants
- Finite element analysis of uplift capacity of enlarged base piles
- Bifurcation pattern analysis of honeycomb structure under biaxial compression
- Evaluation of elastoplastic buckling strength of imperfect plates by sensitivity laws
- Bifurcation analysis of plane-strain sand specimens with elastoplastic constitutive model: examination of the effect of lateral confining conditions
- 2006
- Probabilistic evaluation of structural strength deterioration by initial imperfections or wind loads
- Systematic description of probabilistic variation of buckling loads of elastoplastic plates
- Research on bifurcation analysis of Core-Perphery modell of cities
- 2005
- Verification of generalized imperfection sensitivity laws and evaluation of buckling strength of structures
- Evaluation of uplift behavior of anchors and comparison of large-deformation analysis technique of soils
- Improvement of the accuracy of Scaled Corrector method and proposal of a bifurcation analysis procedure for symmetric structures
- 2004
- Image analysis of progress of deformation in plane strain compression test of sand specimens based on bifurcation mechanism
- Investigation of dynamic response of complex underground structures
- Three-dimensional numerical simulation of the deformation response of the pull out of anchors
- Bifurcation simulation of pattern formation of a honeycomb structure
- 2003
- Plane strain compressiton test of sand specimens and numerical simulation using finite strain Cam-clay model
- Observation of shape effects and localized zones in plain strain compression test of sand specimens
- Numerical simulation of the localization propagation of the pull out of anchors
- 2002
- Bifurcation behavior in bearing capacity analysis of sand foundation
- Determination of mechanical properties in microstructures by response surface method
- The study for the shape transformation in the compression test for sand under the plain strain condition
Master Theses
- 2015
- Inspection of city population aggolomerations in Germany and USA by group-theoretic double Fourier spectra
- Bifurcation and imperfection sensitivity in strength variation of sand specimens with material inhomogeneity
- 2014
- Effect of foundation displacement and soil property on ultimate strength of electric transmission tower
- Study on ductile crack initiation behavior of steel specimen focused on surface property change under the plastic deformation
- 2013
- Study of agglomeration patterns and systematization of bifurcation analysis in a system of places in a two-dimensional space
- Study of influence of topographical condition on agglomeraion of a core-periphery model in two-dimensional spaces
- Subloading surface Cam-clay model with anisotropic rotational hardening for sands at finite strains: Extension and application to cyclic behavior
- 2012
- Analysis of agglomeration patterns of a core-periphery model for economy in one-dimensional spaces
- Study of influence of boundaries on aglomeration of a core-periphery model in two-dimensional spaces
- Behavior of the bifurcation and localization in three-dimensional deformation of sand material
- Development of finite strain elastoplastic model for geomaterials with nonlinear rotational hardening based on the multiplicative decomposition of the plastic deformation gradient tensor
- 2011
- Bifurcation mechanism for a system of cities in two dimensions
- Effect of spatial variability of soil density on strength and localization of deformation in sand specimens
- Evaluation of elasto-plastic ultimate strength of electric transmission tower subject to support movement: soil-foundation-transmission tower coupled analysis
- 2010
- Self-organization of Losch's hexagonal patterns by bifurcation analysis for two-dimensional CP model
- Research on spatial distribution of urban population for Fujita model
- Investigation of the relationship between the insertion direction of implants and stress within mandibular bone using in-vivo measured masticating load
- Effect of the support movement on the structural integrity and member damage of transmission tower
- 2009
- Development of stress-update algorithm for finite-strain anisotropic model for geomaterials
- 2008
- Symmetry-breaking bifurcation of a Core-Periphery model of many cities: Group-theoretic approach
- Bifurcation analysis of spatial agglomeration patterns of a system of cities
- 2007
- Probabilistic evaluation of buckling strength reduction due to live load based on initial imperfection sensitivity law
- Wind response dimulation of overhead wires and evaluation of action on tower and foundations
- Development of implicit stress integration technique for subloading surface Cam-clay model and its application to bearing capacity analysis
- Development of FEM analysis system and investigation of mechanical behavior of a jawbone with implants
- 2006
- Research on bifurcation analysis of Core-Periphery model of city
- Large-scaled elastoplastic analysis of coupled behavior of electric power line system considering soil-pile foundation-tower structure interaction
- Stability analysis of transmission tower on deep foundations considering 3D soil-foundation-structure interaction
- Bifurcation behavior of sand specimens and comparison with elastoplastic analysis
- 2005
- Construction of virtual-reality cities and their assessment under seismisity
Doctor Dissertations
- March, 2011
- Imperfection sensitivity laws for elastic and plastic buckling of bridge structures subjected to random traffic loads
- March, 2006
- Bifurcation analysis of diffuse mode and shear band mode in multiplicative hyperelasto-plastic materials
- March, 2003
- Multi-scale analyses for heterogeneous brittle materials
- Non-linear multi-scale analysis method and its application to the structural design
- February, 2003
- Bifurcation phenomena and material instabilities in shear band formation of geomaterials
- June, 2001
- Instability and pattern formation of materials with internal structures
