• Journal of the Korean Geographical Society
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• v.47 no.1
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• pp.98-120
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• 2012

The main objective of this study is to conduct subnational population projections of Korea based on a multiregional cohort-component method. This objective is accomplished by: (i) establishing a viable framework to implement the multiregional cohort-component method with reference to the Markov chain model and Rogers' multiregional population projection model; (ii) applying the established framework to subnational population projections of Korea, 2005~2030. The main results are twofold. First, the proposed method turns out to be highly valid in a methodological sense, which is seen from a high level of coincidence between the estimated and the observed. Second, the projection results turn out to be highly useful in the sense that interregional migration flow matrices are resulted for projection periods. The projected migration flows are expected to provide invaluable information for an understanding of future population change and for a formulation of policy alternatives. This study is strongly inspired by the multiregional perspective emphasizing the evolution of multiple regional populations interconnected by interregional migration flows rather than the overall national change.

• Korea journal of population studies
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• v.23 no.2
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• pp.5-37
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• 2000

In this paper we have reviewed major theories of international migration by three phases of migration : initiation, perpetuation, and adjustment. Through the review it is found that factors affecting the three phases are not mutually exclusive but interrelated, and argued that for a comprehensive understanding of the phenomena we need a theoretical guideline useful to locate all the important factors associated to the entire process of migration. Neoclassical economic theory which has played a leading role in migration research. fails to be such a guideline. since it is grounded on the unrealistic assumption of rationality and does not take into account for historical-structural factors, as neo-Marxian theorists have claimed. Two major Marxian theories, dual labor market theory and world system theory, have been successful to identify macro-structural factors that induce main flows of international migration, but do not so in exploring situational factors affecting the process of migration, especially social and cultural factors. Accordingly this study proposes that in order to grasp international migration process comprehensively we need to research the phenomena in view of action system theory, that is, to study migrants\` economic, political, social, and cultural situations inclusively.

• Korea-Australia Rheology Journal
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• v.14 no.4
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• pp.203-207
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• 2002

Particle-particle interaction is of great importance in the study of suspension rheology. In this research we have investigated the hydrodynamic interaction between two identical cylinders in viscoelastic fluids numerically as a model problem for the study of viscoelastic suspension. We confine two neutrally buoyant cylinders between two parallel plates and impose a shear flow. We determine the migration velocity of two cylinders. The result shows that cylinders move toward or away from each other depending upon the initial distance between them and that there is an equilibrium distance between two cylinders in viscoelastic fluids regardless of the initial distance. In the case of Newtonian fluid, there is no relative movement as expected. The results partly explain the chaining phenomena of spherical particles in shear flows of viscoelastic fluids.

• Korea-Australia Rheology Journal
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• v.20 no.3
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• pp.143-152
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• 2008

Simulations of solutions of flexible polymer molecules during flow in simple or complex confined geometries are performed. Concentrations from ultradilute up to near the overlap concentration are considered. As concentration increases, the hydrodynamic migration effects observed in dilute solution unidirectional flows (Couette flow, Poiseuille flow) become less prominent, virtually vanishing as the overlap concentration is approached. In a grooved channel geometry, the groove is almost completely depleted of polymer chains at high Weissenberg number in the dilute limit, but at finite concentration this depletion effect is dramatically reduced. Only upon inclusion of hydrodynamic interactions can these phenomena be properly captured.

• SUVANNABHUMI
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• v.15 no.2
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• pp.131-152
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• 2023

In analyzing the Chinese diaspora, this paper explores losses that are encountered within the family in the nation. It argues that increased social and spatial mobilities that contribute to losses can be reconfigured through the productive lens of supermobility, as Laurence J. C. Ma conceptualizes it. Supermobile identities are significant avenues to consider the way that losses traditionally associated with migration and assimilation are revisited in view of new flows of migration and identification. In examining K. H. Lim's debut novel Written in Black (2014), this study addresses pathways from debilitating losses to productive losses journeyed by the family from the child's perspective. It offers a critical analysis of the Anglophone Bruneian novel in terms of its exclusive portrayal of an ethnic Chinese family. Departing from a fixed notion of home as cultural and physical rootedness, it explores flexible identities that are tied to shifting concepts of belonging. Rather than a magnification of social and spatial losses, the analysis highlights the way that the literary imagination of ethnic Chinese in Brunei Darussalam accommodates progressive ideas of the agency and advancement of the Chinese diaspora as a supermobile community.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.3
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• pp.183-195
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• 2007

Comprehensive mathematical comparison of numerical dissipation vector was made for a compressible and the preconditioned version Roe's Riemann solvers. Choi and Merkle type preconditioning method was selected from the investigation of the convergence characteristics of the various preconditioning methods for the flows over a two-dimensional bump. The investigation suggests a way of migration from a compressible code to a preconditioning code with a minor changes in Eigenvalues while maintaining the same code structure. Von Neumann stability condition and viscous Jacobian were considered additionally to improve the stability and accuracy for the viscous flow analysis. The developed code was validated through the applications to the standard validation problems.

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.40-60
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• 2020

Among Filipino entertainers in Japan, trans women (transgender women) or transpinay (Filipino trans woman) entertainers remain understudied compared to cisgender women. Though the number of entertainers has declined, transpinay entertainers remain relevant as transgender issues continue to be salient globally. This study explains the gendered experiences of the transpinay migrants, particularly in entertainment work and their relationships, which are different from cisgender Filipino women entertainers' experiences. Using grounded theory and drawing on concepts of performativity in interactions to analyze the narratives of transpinay entertainers, I delve into how transpinay entertainers negotiate their gender and migrant identities as they establish professional and personal relationships. Moreover, the transpinays' entertainment work is a significant contributing factor to their sense of belonging in Japan, as they form relationships with colleagues, clients, and partners who support them and, thereby, sustain their lifestyles as trans women. The transpinay entertainers' flows of migration between Japan and the Philippines reveal that they embrace various aspects of social remittances and use them to their advantage to create and enhance their transpinay identity in Japan. By examining the transpinays' migrant experiences, this study aims to elucidate the gendered experiences of transpinay entertainers, which involve significant negotiations in their migration pathways notably different from cisgender Filipino women entertainers, reveal resilience.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.5
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• pp.573-580
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• 2002

Animation and time-resolved analysis of the wake characteristics of 2-D bluff body flows were examinated by applying the multi-vision PIV to square cylinders(three angles of attack: $0^{circ}, 30^{circ} and 45^{\circ}$) and circular cylinders(three rotating speeds: 0rpm, 76rpm, 153rpm) submerged within a circulating water channel $(Re=10^4)$, The macroscopic shedding patterns and their dominant frequencies were discussed in terms of instantaneous velocity, vorticity and turbulent quantities such as turbulent intensity, turbulent kinetic energy and three Reynolds stresses. Particularly the time-averaged distribution of turbulent intensity 'islands' where their peak magnitudes were focused always small regions behind the bodies without noticeable spatial migration were particularly discovered in all cases. And the dominant frequencies of the turbulent quantities in the wake regions were two times larger than those of the velocity and vorticity.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.162-176
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• 2022

In Lead-based reactor (LBR) severe accident, the meltdown and migration inside the reactor core will lead to fuel fragment concentration, which may further cause re-criticality and even core disintegration. Accurately predicting the migration and solidification behavior of melt in LBR severe accidents is of prime importance for safety analysis of LBR. In this study, the Moving Particle Semi-implicit (MPS) method is validated and used to simulate the migration and solidification behavior. Two main surface tension models are validated and compared. Meanwhile, the MPS method is validated by the L-plate solidification test. Based on the improved MPS method, the migration and solidification behavior of melt in LBR severe accident was studied furthermore. In the Pb-Bi coolant, the melt flows upward due to density difference. The migration and solidification behavior are greatly affected by the surface tension and viscous resistance varying with enthalpy. The whole movement process can be divided into three stages depending on the change in velocity. The heat transfer of core melt is determined jointly by two heat transfer modes: flow heat transfer and solid conductivity. Generally, the research results indicate that the MPS method has unique advantage in studying the migration and solidification behavior in LBR severe accident.

• Journal of the Korean association of regional geographers
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• v.11 no.2
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• pp.169-186
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• 2005

This paper has focused on the geographical patterns of migrations and the influence of housing value(apartment) per pyung on the migrations within the one city(Seoul) for 1995$\sim$2003. The migration flows which are composed of the origin, the destination and the number of migrants, are examined at the administrative gu and dong level. As most migrations occur among adjacent gus and dongs, short-distance migration is prominent But there is a tendency for the short-distance migrations to occur between specific regions. Since the economic crisis of 1997 out of which Korea was rescued by IMF, differentiation of housing price is so evident that residental relocation is selective among dongs. It seems that the differentiation of housing price has begun to facilitate the relocation of households. Certain social groups are excluded from high-quality residences, as they cannot afford the high price. The number of migrants between dongs is closely related to the variation of the housing value per pyung within dongs. The short-distance migration may reflect this phenomena simultaneously. It seems that the intra-urban migrations in Seoul play a important role to produce and reinforce the residential segregation.