• Journal of Ocean Engineering and Technology
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• v.34 no.2
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• pp.128-135
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• 2020

When high waves and storm surge strike simultaneously, the characteristics of the fluid field change drastically from overtopping according to the wave runup height to overflow through a transition state that combines overtopping and overflows. However, an estimation model or evaluation method has not yet been established because there is not enough engineering data. This study developed a wave overtopping-overflow transition model based on a full-scale experiment involving wave overtopping and overflow transition, which appropriately reproduced the effect of waves or the temporal change in inundation flow. Using this model to perform a calculation for the wave overtopping and overflow transition process under typical circumstances, this study determined the wave runup height and features of the inundation flow under time series changes as an example.

• Journal of the Korean Home Economics Association
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• v.31 no.3
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• pp.127-141
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• 1993

The purpose of this study was to investigate Couple's dyadic Adjustment Change across the transition to parenthood. Change in marital adjustment following the birth of the first child was examined in a longitudinal study of 62 couples. The couples completed a series of questionnaires during pregnancy as well as at three months postpartum. The major findings were as follows. 1) The marital adjustment declined significantly over time. Especially, for wives, the transition to parenthood had a negative effect on postpartum marital adjustment. 2) The transition of wives differed from that of husbands. 3) The result of a single regression indicated that, for wives and husbands, the pregnancy marital adjustment had an effect on postpartum marital adjustment. 4) The influence of variables that had an effect on pregnancy marital adjustment changed in the postpartum marital adjustment.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.281-288
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• 2001

In order to evaluate the effect of impact load at support stiffness transition area, the field estimations are performed at the transition zone between earthwork and bridge on test operation of KTX. Due to differential settlement caused by the variations of track support stiffness, large impact forces are investigated. However, the measured values such as wheel load, rail stress, displacement and acceleration in the transition area shows that the stiffness changes in the transition area are not abrupt, and the stiffness in the infra track structure varies continuously. In this experimental study, the parameters influencing safety of transition area are not governed by partial or local stiffness because cumulative passing loads are not sufficient on test operation of KTX.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.114-132
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• 2011

We have proposed a new approach based on energy gradient concept for the study of flow instability and turbulent transition in parallel flows in our previous works. It was shown that the disturbance amplitude required for turbulent transition is inversely proportional to Re, which is in agreement with the experiments for imposed transverse disturbance. In present study, the energy gradient theory is extended to the generalized curved flows which have much application in turbomachinery and other fluid delivery devices. Within the frame of the new theory, basic theorems for flow instability in general cases are provided in details. Examples of applications of the theory are given from our previous studies which show comparison of the theory with available experimental data. It is shown that excellent agreement has been achieved for several configurations. Finally, various prediction methods for turbulent transition are reviewed and commented.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.2
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• pp.165-179
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• 2010

The purpose of this study was to analyze career behaviors(job exploration, job hunting) of the need mode in the women's second labor market transition. To obtain this objective 501 women, who quitted their job in 780 women randomly sampling completed questionnaire. To analyze data, $x^2$, ANOVA were executed. Research results were explained, there were no difference career behaviors, experience of career counseling, experience of career education, aspiration of career behaviors by the need mode in the women's second labor market transition. But, there were difference motivation of labor market entry, career barriers, preference of occupations, level of job competence of career behaviors by the need mode in the women's second labor market transition. The implications of the results on women's second labor market transition of developing career education and counseling programs were discussed and finally suggestions for further study were made.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.43-52
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• 2005

Signal timing transition has recently been highlighted with Adaptive Traffic Control Systems (ATCS) providing advanced traffic signal operation including real-time grouping of coordinated intersections. Signal timing transition occurs when such signal timings as cycles and offsets are changed at coordinated intersections. Setting a proper length of signal timing transition has become in interest for real-time coordination. This paper presents a study verifying the effects of different lengths of signal timing transition. Four different transition lengths were tested and compared in simulation environment. They include a single, double, treble, quadruple cycle length transitions. The number of cycles represents the ones used (interpolation) for transition. Signal timings were controlled to be adjusted uniformly and discretely during a transition period. Transition times considered in the test are within ranges of ${\pm}20$ percents of cycle lengths. It was found from the study that a single cycle transition performs better than or at least equal to the ones from the other with fifteen different operational conditions, which are developed based on a hypothetical arterial. It was suggested that a single cycle length transition be beneficial when amount of transition is within ${\pm}20$ percents of cycle lengths.

• Advances in concrete construction
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• v.8 no.3
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• pp.173-185
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• 2019

This article presents a comparative study of the effect of steel layouts on the seismic behavior of transition steel-concrete composite connections, both experimental and analytical investigations of concrete filled steel tube-reinforced concrete (CFST-RC) and steel reinforecd concrete-reinforced concrete (SRC-RC) structures were conducted. The steel-concrete composite connections were subjected to combined constant axial load and lateral cyclic displacements. Tests were carried out on four full-scale connections extracted from a real project engineering with different levels of axial force. The effect of steel layouts on the mechanical behavior of the transition connections was evaluated by failure modes, hysteretic behavior, backbone curves, displacement ductility, energy dissipation capacity and stiffness degradation. Test results showed that different steel layouts led to significantly different failure modes. For CFST-RC transition specimens, the circular cracks of the concrete at the RC column base was followed by steel yielding at the bottom of the CFST column. While uncoordinated deformation could be observed between SRC and RC columns in SRC-RC transition specimens, the crushing and peeling damage of unconfined concrete at the SRC column base was more serious. The existences of I-shape steel and steel tube avoided the pinching phenomenon on the hysteresis curve, which was different from the hysteresis curve of the general reinforced concrete column. The hysteresis loops were spindle-shaped, indicating excellent seismic performance for these transition composite connections. The average values of equivalent viscous damping coefficients of the four specimens are 0.123, 0.186 and 0.304 corresponding to the yielding point, peak point and ultimate point, respectively. Those values demonstrate that the transition steel-concrete composite connections have great energy dissipating capacity. Based on the experimental research, a high-fidelity ABAQUS model was established to further study the influence of concrete strength, steel grade and longitudinal reinforcement ratio on the mechanical behavior of transition composite connections.

• Journal of Korea Technology Innovation Society
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• v.22 no.1
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• pp.1-27
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• 2019

This study deals with the changes in the government-funded research institutes (GRI) in terms of 'responding to social challenges and turning to the institutes that are pursuing sustainability transition'. The newly established societal problem-solving R&D projects in GRIs are core experiments for the transition. In order to discuss about the prospect of transition of GRIs, this study used focus group interview approach. In the interview, the GRIs's stance on the societal problem-solving R&D projects, and its process, problems and the policy direction had been discussed. It is suggested that the necessity of transition is discussed and transition experiments are proceeding on a small scale, but experiments are still underway in the existing framework. In order to facilitate the transition in GRIs, it is necessary to carry out the experiment and the vision making work from the inside the GRI.

• The Korean Journal of Ceramics
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• v.3 no.2
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• pp.82-87
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• 1997

High pressure FTIR and Raman spectra of soild $C_{70}$ were measured at pressure up to 11 GPa and room temperature. The slope (dv/dp) of the frequency-pressure plots for several IR and Raman mode changed around 1.5 GPa, where a solid-solid transition might occur. In IR study, we can observe new mode appeared around 777$cm^{-1}$1 above 5.5 GPa which might indicate another solid-solid transition. Our study showed that this transition might be irreversible.

• Advances in concrete construction
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• v.1 no.3
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• pp.239-252
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• 2013

Mortar microstructure is considered as a three-phase composite material, which is cement paste, fine aggregate and interfacial transition zone. Interfacial transition zone is the weakest link between the cement paste and fine aggregate, so it has a significant role to determine the properties of cementitious composites. In this study, specimens (w/c = 0.35, 0.45, 0.55) with various volume fractions of fine aggregate ($V_f$ = 0, 0.1, 0.2, 0.3 and 0.4) were cast and tested. To predict the equivalent migration coefficient ($M_e$) and migration coefficient of interfacial transition zone ($M_{itz}$), double-inclusion method and Mori-Tanaka theory were used to estimate. There are two stages to estimate and calculate the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$). The first stage, the data of experimental chloride ion migration coefficient ($M_s$) was used to calculate the equivalent migration coefficient of fine aggregate with interfacial transition zone ($M_e$) by Mori-Tanaka theory. The second stage, the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$) was calculated by Hori and Nemat-Nasser's double inclusion model. Between the theoretical and experimental data a comparison was conducted to investigate the behavior of interfacial transition zone in mortar and the effect of interfacial transition zone on the chloride migration coefficient, the results indicated that the numerical simulations is derived to the $M_{itz}/M_m$ ratio is 2.11~8.28. Additionally, thickness of interfacial transition zone is predicted from $10{\mu}m$, 60 to $80{\mu}m$, 70 to $100{\mu}m$ and 90 to $130{\mu}m$ for SM30, M35, M45 and M55, respectively.