• Bulletin of the Korean Chemical Society
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• v.19 no.5
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• pp.539-544
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• 1998

A new theoretical method, named the SCF-DWB-IOS approximation, is suggested to investigate the vibrational predissociation of triatomic van der Waals complexes. The meta stable vibrational excited states are described with SCF (self-consistent-field) approximation and the fragmented diatomic continuum states are determined by using IOS (infinite order sudden) approximation. The dissociation process itself is studied by using DWB (distorted wave Born) approximation. As a test case, the predissociation rates, rotational state distributions of products, and the lifetimes of vibrationally excited states of $Ne-I_2$ are all computed which are in reasonable agreements with other theoretical and/or experimental results. The suggested SCF-DWB-IOS approximation scheme is found to be a very simple but efficient theoretical tool to investigate the vibrational predissociation dynamics of small van der Waals complexes.

• Progress in Superconductivity and Cryogenics
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• v.25 no.2
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• pp.1-4
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• 2023

Over the past decade, the exploration of high-temperature superconductivity and the discovery of a wide range of exotic superconducting states in Fe-based materials have propelled condensed matter physics research to new frontiers. These materials exhibit intriguing phenomena arising from their multiband electronic structure, strongly orbital-dependent effects, extremely small Fermi energy, electronic nematicity, and topological aspects. Among the various factors influencing their superconducting properties, high magnetic fields play a crucial role as a control knob capable of disrupting the subtle balance between the spin, charge, lattice, and orbital degrees of freedom, leading to the emergence of various exotic superconducting states. In this review, we provide an overview of the current understanding of the exotic superconducting states observed in Fe-based superconductors, with a particular focus on FeSe and Sr₂VO₃FeAs, under the influence of high magnetic fields.

• The Journal of Information Systems
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• v.12 no.2
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• pp.109-128
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• 2003

This study is intended to suggest an ideal direction of the information systems policy for the local small business firms. In an effort to accomplish this objective, this paper tried to identify the current states of the information systems and measure the level of the information systems of local small business firms based on the maturity stage and the development level. The study then explored the evidence how the maturity stage and the development level affect the business performance of the local small business firms. The research found out that the organizational factor such as the support of CEO and the financial factor such as IS investment took major roles to improve the business performance. Based on the research findings of this study, the paper suggested the desirable solution of the information system policy to deal with the problems the local small business firms need to overcome.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.2
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• pp.69-74
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• 2017

These days as there are a growing vessel volume in the costal area, the marine accidents has being increased. IMO recommend that all vessels have to be equipped with the safety equipments mandatorily for the safety navigation. Almost medium and large size vessels are equipped with the safety navigational equipments, But many small size vessels are not equipped with those ones because of its owner's financial hardship or indifference. So for the safety of small size vessels in the coastal area, the marine accidents such as stranding, sinking, collision, and so on, have to be protected in advance or the occurred accidents has to be treated quickly. In this paper, the safety equipment for small size vessels having these functions has been developed. This equipment can guarantee the safety of small size vessels in defenseless state considerably by displaying these states in seamen's Smart phone or the cheap dedicated terminal and also informing the control center and nearby other vessels of these states.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.5
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• pp.60-67
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• 2003

For risk or reliability assessment of ship structures against particular hazardous situations such as total loss or sinking due to hull girder collapse, the short-term based response analysis rather than the long-term response analysis is required to determine wave-induced bending moments when the ship encounters a storm of specific duration and with a specified small encounter probability. In the present study, the effects of operational condition and sea states on wave-induced bending moments of large merchant vessels are investigated. A series of the short-term response analyses for a hypothetical VLCC and a Capesize bulk carrier (CSBC) are carried out with varying operational condition and sea states which include ship speed, significant wave height and wave persistence time, using the linear-strip theory based program ABS/SHIPMOTION and the MIT sea-keeping tables. The computed results are also compared with the IACS design formula predictions. The results and insights developed from the present study are summarized.

• Health Policy and Management
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• v.17 no.1
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• pp.94-124
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• 2007

This paper critically reviews three decades of research on geographic variations. in health services utilization in the United States, thereby drawing policy and research implications for Korea. The recent renewed interest in variations research in the United States, precipitated by studies on regional variations in Medicare expenditures, stems mainly from the policy implication that a substantial amount of Medicare expenditures could be saved without compromising quality and access. From the research perspective, this policy implication was made tenable by integrating micro- and macro-level analysis of variations in health services utilization. Still, theoretical limitations inherent in the research pose great challenges to developing effective strategies at the health system level. Variations research in the United States can serve as a case study as to how health services research has responded to efficiency and quality issues in an ever expanding health system Considering the current health policy and research environment in Korea, the following implications can be drawn. Variations research will help formulate a national policy agenda for health care quality and also advance the framework of approaches to health policy issues. For such purposes, both relevant descriptive and hypothesis-testing studies are needed. Further advancement in variations research will require interdisciplinary explorations and methodological sophistication. To the extent that Korean health policies will strive to achieve complex goals, variations research will increasingly prove to be useful.

• Earthquakes and Structures
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• v.8 no.3
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• pp.591-617
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• 2015

Standards for seismic assessment and retrofitting of buildings provide deformation limit states for structural members and connections. However, in order to perform fully consistent performance-based seismic analyses of soil-structure systems; deformation limit states must also be available for foundations that are vulnerable to nonlinear actions. Because such limit states have never been established in the past, a laboratory testing program was conducted to study the rotational capacity of small-scale foundation models under combined axial load and moment. Fourteen displacement-controlled monotonic and cyclic tests were performed using a cohesionless soil contained in a $2.0{\times}2.0{\times}1.2m$ container box. It was found that the foundation models exhibited a stable hysteretic behavior for imposed rotations exceeding 0.06 rad and that the measured foundation moment capacity complied well with Meyerhof's equivalent width concept. Simplified code-based soil-structure analyses of an 8-story building under an array of strong ground motions were also conducted to preliminary evaluate the implication of finite rotational capacity of vulnerable foundations. It was found that for the same soil as that of the experimental program foundations would have a deformation capacity that far exceeds the imposed rotational demands under the lateral load resisting members so yielding of the soil may constitute a reliable source of energy dissipation for the system.

• Journal of Korean Society of Rural Planning
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• v.26 no.4
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• pp.107-116
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• 2020

The purpose of this study is to analyze the characteristics of the 11 southeastern states in the United States by using regional characteristics variables and to classify the regions. First, 19 variables from four categories of population, society, industry-economy and urban service were selected and factor analysis were conducted, and the result showed five major factors of population, economic condition, job and commuting. Based on the following factor scores, a cluster analysis was conducted, and eight types of big city, medium-sized city, bed town, small town, urban hinterland, retirement town, and rural village were derived. These types of spatial distribution characteristics showed big cities were by different types of regions and they formed metropolitan areas. Each types of classified regions were located along the road network with hierarchy. The study focused on cases in the southeastern regions of the United States and can be used as a comparison with Korean cases. If the same research method is applied to Korea in the future, or if the time series of changes is tracked by analyzing different time points, it will greatly help identify the characteristics of urban and rural mixed areas.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.547-552
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• 1995

As an extension to the Kramers' restricted Hartree-Fock (KRHF) method [J. Comp. Chem., 13, 595 (1992)], we have implemented the Kramers' restricted configuration interaction (KRCI) program in order to calculate excited states as well as the ground state of polyatomic molecules containing heavy atoms. This KRCI is based on determinants composed of the two-component molecular spinors which are generated from KRHF calculations. The Hamiltonian employed in the KRHF and KRCI methods contains most of all the important relativistic effects including spin-orbit terms through the use of relativistic effective core potentials (REP). The present program which is limited to a small configuration space has been tested for a few atoms and molecules. Excitation energies of the group 14 and 16 elements calculated using the present KRCI program are in good accordance with the spectroscopic data. Calculated excitation energies for many Rydberg states of K and Cs indicate that spin-orbit terms in the REP, which are derived for the ground state, are also reliable for the description of highly excited states. The electronic states of the polyatomic molecule CH3I are probed from the molecular region to the dissociation limit. Test calculations demonstrate that the present KRCI is a useful method for the description of potential energy surface of polyatomic molecules containing heavy atoms.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.230-235
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• 1992

The conformational analysis has been done for catecholamines (dopamine, norepinephrine, and epinephrine) in the cationic and di-anionic states. The species responsible for adsorption on silver metal surface is anionic deprotonated at hydroxyl groups of catechol moiety, i.e., di-anionic states of catecholamines. This was deduced from Fourier-transform Raman spectra of sodium salts of catecholamines. High resolution proton NMR (400 MHz) spectra of catecholamines in basic and neutral $D_2O$ solution show that the conformations of norepinephrine and epinephrine in the di-anionic states are preferred in gauche, but not for dopamine in the di-anionic state. However the energy difference between trans and gauche of catecholamines in the protonated cationic states is small enough to rotate freely through C-C bond in ethylamine moiety. The conformational calculations using an empirical potential function and the hydration shell model (a program CONBIO) show consistent with above experimental results. The calculations suggest that the species of catecholamines adsorbed on silver metal surface would be in favor of the gauche conformations.