• BMB Reports
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• v.39 no.2
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• pp.167-170
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• 2006

Bovine adenosine deaminase undergoes a nondenaturational conformational change at $29^{\circ}C$ upon heating which is characterized by a large increase in heat capacity. We have determined the transition state thermodynamics of the conformational change using a novel application of differential scanning calorimetry (DSC) which employs very slow scan rates. DSC scans at the conventional, and arbitrary, scan rate of $1^{\circ}C/min$ show no evidence of the transition. Scan rates from 0.030 to $0.20^{\circ}C/min$ reveal the transition indicating it is under kinetic control. The transition temperature $T_t$ and the transition temperature interval ${\Delta}T$ increase with scan rate. A first order rate constant $k_1$ is calculated at each $T_t$ from $k_1\;=\;r_{scan}/{\Delta}T$, where $r_{scan}$ is the scan rate, and an Arrhenius plot is constructed. Standard transition state analysis reveals an activation free energy ${\Delta}G^{\neq}$ of 88.1 kJ/mole and suggests that the conformational change has an unfolding quality that appears to be on the direct path to the physiological-temperature conformer.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1809-1816
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• 2014

This study demonstrates gel-to-fluid transition temperatures of polydiacetylene bilayer vesicles could play important roles in their colorimetric transition temperatures. We prepared five types of polydiaceylene vesicles with 10,12-pentacosadiynoic acid (PCDA) and cholesterol (0-40 mol % of total content). From temperature-dependent observations of the optical signals (colors and UV-vis spectra), the blue-to-red colorimetric transition temperatures of polydiacetylene vesicles were decreased with the cholesterol contents. A further study with microcalorimetry and dynamic light scattering revealed that the polydiacetylene vesicles first underwent gel-to-fluid transitions, which were followed by event(s) responsible for the colorimetric transitions. Energies required for each event were quantified from analysis of the peaks in the microcalorimetry thermograms. The inclusion of cholesterol in the vesicles decreased both the gel-to-fluid and the colorimetric transition temperatures, suggesting that the colorimetric transition of the polydiacetylene vesicles was mediated by the former event although the event was not the direct reason for the color change.

• Journal of IKEEE
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• v.23 no.2
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• pp.502-507
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• 2019

We investigated theoretically the quantum optical transition properties of qusi 2-Dinensinal Landau splitting system, in Si. We apply the Quantum Transport theory (QTR) to the system in the confinement of electrons by square well confinement potential. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS). In order to analyze the quantum transition, we compare the temperature and the magnetic field dependencies of the QTLW and the QTLS on two transition processes, namely, the phonon emission transition process and the phonon absorption transition process. Through the analysis of this work, we found the increasing properties of QTLW and QTLS of Si with the temperature and the magnetic fields. We also found the dominant scattering processes are the phonon emission transition process.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.4
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• pp.356-366
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• 2022

This paper presents a mode transition method that applies frequency compensation technique of an LLC resonant converter for stable mode transition. LLC resonant converters used in various applications require high efficiency and high power density. However, because of circuit property, a wider voltage gain range equates to a greater circuit loss, so maintaining high efficiency at all voltage gain ranges is difficult. In this case, full bridge-half bridge mode transition method can be used, which maintains high efficiency even in a wide voltage gain range. However, this method causes damage to the circuit through overcurrent by the mode transition. This study analyzes the cause of the problem and proposes a mode transition method that applies frequency compensation technique to solve the problem. The proposed method verifies the stable transition through simulation analysis and experimental results.

• Bulletin of the Korean Chemical Society
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• v.17 no.7
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• pp.653-655
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• 1996

A comparative molecular field analysis (CoMFA) was carried out for the correlation of the transition state structures and the reaction rates for the SN2 reaction of 4-nitrophenyl benzoate and its sulfur analogs with anionic nucleophiles. The CoMFA analysis showed that both steric and electrostatic effects are important, and the steric contribution increased when nucleophiles are alkoxides or arylsulfides. In this study, we have demonstrated that the CoMFA analysis can be expanded beyond the scope of dealing with reactants and products. The reactant complex and transition state conformations generated along the reaction path can be more appropriately used for the correlation of structures and reaction rates.

• Korea Trade Review
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• v.47 no.4
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• pp.215-231
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• 2022

Analysis and forecasting of the Baltic Capsize Index (BCI) is important for managing an entity's losses and risks from the uncertainty and volatility of the fast-changing maritime transport market in the future. This study conducted volatility transition analysis through the GARCH model, using BCI which is highly related to steel raw materials. As for the data, 2,385 monthly data were used from March 1999 to March 2021. In this study, after basic statistical analysis, unit root and cointegration test, the GARCH, EGARCH, and DCC-GARCH models were used for volatility transition analysis. As the results of GARCH and EGARCH model, we confirmed that all variables had no autocorrelation between the standardized residuals for error terms and the square of residuals, that the variability of all variables at this time was likely to persist in the future, and that the variability of the time-series error term impact according to Iron ore trade (IoT). In addition, through the EGARCH model, the magnitude convenience of all variables except the Iron ore price (IOP) and Capesize bulk fleet (BCF) variables was greater than the positive value (+). As a result of analyzing the DCC-GARCH (1,1) model, partial linear combinations were confirmed over the entire period. Estimating the effect of variability transition on BCF and C5 with statistically significant linear combinations with BCI confirmed that the impact of BCF on BCI was greater than the impact of BCI itself.

• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.199-205
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• 2005

In general, simple correspondence analysis has handled mainly correspondence relations between the row and column categories but can not display the trends of their change over the time. For solving this problem, we will propose DSCA(Dynamic Simple Correspondence Analysis) of transition matrix data using supplementary categories in this study, Moreover, DSCA provides its trend of the change for the future by predicting and displaying trend toward the change from a standard point of time to the next.

• Journal of Korean Tunnelling and Underground Space Association
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• v.14 no.6
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• pp.653-666
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• 2012

This study made progress about Demage Mechanism of Transition Section in Cut and Cover Tunnel. For this study, Inspection and test was carried out about Transition Section. After this process, Numerical Analysis was accomplished by 2D, 3D. A result of inspection and test, It couldn't find the reason why the upper slab Demage was detected. So 2D Numerical Analysis was conducted. It was analyzed that the Safety Factor(1.0) was satisfied in 2D. But, the result of 3D Numerical Analysis, The reason was found that the Demage on upper slab was caused by moment change. The Moment was changed by column interval transition. For Retrofitting, Column was added under slab in tunnel. It was found that the addition column decreased upper slab deformation. After this study, It could be find that are important 3D Numerical Analysis as well as 2D Numerical Analysis in case of Transition Section. This Study can help developing construction and maintenance about Tunnel. Finally, It's going to study Retrofitting plans which have minimum influence of Transition Section in Cut and Cover Tunnel.

• The Journal of Korean Physical Therapy
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• v.23 no.5
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• pp.49-56
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• 2011

Purpose: The purpose of this study was to investigate the kinematic characteristics and muscle activities during the following two conditions: transition from half-kneel to standing on the affected leg and non-affected leg. Methods: Twenty-one hemiplegic patients participated in the study. A motion analysis system was used to record the range of motion and angle velocity of the hip, knee and ankle from the half-kneel to the standing position. Electromyography was used to record the activity of 4 muscles. Results: The statistical analysis showed that the minimum ROM of the hip joint was less on the affected leg during transition from half-kneel to standing. However, the minimum ROM of the knee and ankle joints was less on the non-affected leg during transition from half-kneel to standing. The angle velocity of the knee and ankle joints was less during transition from half kneeling to standing on the non-affected leg. Muscle activity of the rectus femoris and tibialis anterior was less while moving from half-kneel to the standing position on the affected leg. Conclusion: These results show that greater active ROM of the knee and ankle was required on the affected leg for transition from half-kneel to the standing position than for normal gait. Muscle activity of the rectus femoris and tibialis anterior is normally required for movement from the half-kneel to the standing position during normal gait. Further studies are needed to investigate the antigravity movement in healthy subjects and hemiplegic patients in order to completely understand the normal and abnormal movement from the half-kneel to the standing position.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.1-12
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• 2021

In the design of a tunnel boring machine (TBM), the excavation efficiency of the equipment depends on the design of the cutter head, which is directly in contact with the ground. Especially, the allocation of disc cutter is crucial issue. Disc cutters can be divided into center cutter zone, inner cutter zone and transition cutter zone depending on where they are placed. Many studies have been conducted to identify optimal cutting conditions for face cutters. However, research to determine the optimal cutting conditions for the transition cutter has been relatively incomplete. In this study, to identify the optimal cutting conditions for the transition cutter, numerical analysis using discrete element method was performed, and the specific energy curve according to the angle between the transition cutters was drawn to find out the optimum cutting conditions. The results show that the angle between the transition cutters showing minimum specific energy in the transition cutter zone is 9°. Transition cutter zone was divided into three sections according to the slope angle of the transition cutter. It is also found that, the greater the slope angle of the transition cutter. This finding shows good agreement with the present design of transition cutter zone.