• Title/Summary/Keyword: Transition Model

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Role Transition of Senior Year Nursing Students: Analysis of Predictors for Role Transition (간호대학 4학년생이 지각한 간호사로의 역할 이행과 영향 요인)

  • Lee, Worlsook;Uhm, Ju-Yeon;Lee, Taewha
    • Journal of Korean Academy of Nursing Administration
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    • v.20 no.2
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    • pp.187-194
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    • 2014
  • Purpose: The purpose of this study was to identify the perception of role transition from a student nurse to a registered nurse among senior year nursing students and to examine factors affecting their role transition. Methods: A descriptive survey with convenience sampling was conducted in four nursing colleges in Seoul, South Korea. Data were collected using a self-administrated questionnaire. Four instruments including role transition, self-esteem, interpersonal relationships and anxiety during clinical practicum were used and the students'demographics were also collected. A multiple logistic regression was used to identify predictors for the role transition. Results: A total of 233 nursing students were surveyed and final analysis was conducted utilizing 226 participants. Mean point of perceived role transition (5 point scale) was $3.34{\pm}0.44$. In a multiple regression model, high self-esteem, good interpersonal relationships, low anxiety during clinical practicum, and high satisfaction in college life were significant predictors of a smooth transition (Adj. $R^2$=.32, F=22.28, p<.001). Conclusion: The findings suggest that role transition from a student nurse to a registered nurse is facilitated through the establishment of programs to improve self-esteem and interpersonal relationships and to reduce anxiety during clinical practicum.

Numerical Simulations on Nonlinear Behaviors of Diffusional-Thermal Instabilities in Counterflow Diffusion Flames (대향류 확산화염에서 확산-전도 불안정의 비선형 거동에 대한 수치해석)

  • Lee, Su-Ryong;Kim, Jong-Su
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.5
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    • pp.695-702
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    • 2002
  • Nonlinear dynamics of striped diffusion flames, by the diffusional-thermal instability with Lewis numbers sufficiently less than unity, is numerically investigated by examining various two-dimensional flame-structure solutions. The Lewis numbers for fuel and oxidizer are assumed to be identical and an overall single-step Arrhenius-type chemical reaction rate is employed in the model. Particular attention is focused on identifying the flame-stripe solution branches corresponding to each distinct stripe pattern and hysteresis encountered during the transition. At a Damkohler number slightly greater than the extinction Damkohler number, eight-stripe solution first emerges from one dimensional solution. The eight-stripe solution survives Damkohler numbers much smaller than the extinction Damkohler number until the transition to four-stripe solution occurs at the first forward transition Damkohler number. At the second forward transition Damkohler number, somewhat smaller than the first transition Damkohler number, the transition to two-stripe solution occurs. However, anu further transition from two-stripe solution to one-stripe solution is not always possible even if one-stripe solution can be independently accessed for particular initial conditions. The Damkohler number ranges for two-stripe and one-stripe solutions are found to be virtually identical because each stripe is an independent structure if distance between stripes is sufficiently large. By increasing the Damkohler number, the backward transition can be observed. In comparison with the forward transition Damkohler numbers, the corresponding backward transition Damkohler numbers are always much greater, thereby indicating significant hysteresis between the stripe patterns of strained diffusion flames.

Circuit Modeling of Transition from Stripline to Dual Slotline for the Notch Antenna

  • So, Joon-Ho;Kim, Jun-Yeon;Lee, Moon-Que;Cheon, Chang-Yul
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.2 no.1
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    • pp.22-29
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    • 2003
  • A circuit model for the transition of stripline to dual slotline and a segmented method to analyze a notch antenna are presented. For the circuit model of the transition, the characteristic impedance, dispersions, and the shorted impedance of dual slotline are calculated and approximated with the closed-form expressions. The segmented analysis method allows to get readily an optimized results for the dual slotline-fed notch antenna. As a design example, a notch antenna is segmented into a 4'h order Marchand balun and a dual slot 134 notch antenna, and tested to show the validity of the proposed circuit model.

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Simulation of a Diffusion Flame in Turbulent Mixing Layer by the Flame Hole Dynamics Model with Level-Set Method (Level-Set 방법이 적용된 Flame Hole Dynamics 모델을 통한 난류 혼합층 확산화염의 모사)

  • Kim, Jun-Hong;Chung, S.H.;Ahn, K.Y.;Kim, J.S.
    • Journal of the Korean Society of Combustion
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    • v.9 no.2
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    • pp.18-29
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    • 2004
  • Partial quenching structure of diffusion flames in a turbulent mixing layer has been investigated by the method of flame hole dynamics in oder to develope a prediction model for the phenomenon of turbulent flame lift off. The present study is specifically aimed to remedy the shortcoming of the stiff transition of the conditioned partial burning probability across the crossover condition by employing the level-set method which enables us to include the effect of finite flame edge propagation speed. In light of the level-set simulation results with two models for the edge propagation speed, the stabilizing conditions for turbulent lifted flame are suggested. The flame hole dynamics combined with the level-set method yields a temporally evolving turbulent extinction process and its partial quenching characteristics is compared with the results of the previous model employing the flame-hole random walk mapping based on three critical scalar dissipation rates. The probability to encounter reacting state, conditioned with scalar dissipation rate, demonstrated that the conditional probability has a rather gradual transition across the crossover scalar dissipation rate. Such a smooth transition is attributed to the finite response of the flame edge propagation.

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Influence of Thermodynamic Properties upon Transcritical Nitrogen Injection

  • Tani, Hiroumi;Teramoto, Susumu;Nagashima, Toshio
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.03a
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    • pp.320-329
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    • 2008
  • The influence of thermodynamic transition associated with transcritical nitrogen injection upon the flow structure was investigated to explore numerical simulation of the injectant dynamics of oxygen/hydrogen coaxial jet in liquid rocket engines. Single and coaxial nitrogen jets were treated by comparing the transcritical and perfect-gaseous conditions, wherein the numerical model was accommodative to the real-fluid thermodynamics and transport properties at supercritical pressures. The model was in the first place validated by comparing the results of transcritical nitrogen injection between calculations and available experiments. For a single jet under the transcritical condition, the nitrogen kept a relatively high density up to its pseudo-critical temperature inside the mixing layer, since it remains less expanding until heated up to its pseudo-critical temperature. Numerical analysis revealed that cryogenic jets exhibit strong dependence of specific enthalpy profile upon the associated density profile that are both dominated by turbulent thermal diffusion. In the numerical model, therefore, exact evaluation of turbulent heat fluxes becomes very important for simulating turbulent cryogenic jets under supercritical pressures. Concerning the coaxial jets due to transcritical/gaseous nitrogen injections, the density profile inside the mixing layer was again affected by the thermodynamic transition of nitrogen. However, hydrodynamic instability modes of the inner jet did not show significant differences by this thermodynamic transition, so that further study is needed for the mixing process downstream of the near injection position.

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A Longitudinal Analysis of the Association between Transition into Marriage and Life Satisfaction and Childhood Parental Divorce as a Moderator (결혼과 삶의 만족도의 관계에 대한 종단분석 및 아동기 부모 이혼의 조절효과)

  • Lee, Yoonjoo
    • Human Ecology Research
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    • v.59 no.1
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    • pp.113-125
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    • 2021
  • Previous research on the association between marriage and life satisfaction is limited due to the lack of attempts to investigate the time profiles of life satisfaction around marriage. This study addresses unresolved questions about the positive association between marriage and life satisfaction as well as tests if it is moderated by childhood parental divorce. Using 14 waves of the Korean Welfare Panel Study(N=3,890 individuals or 25,338 person-year observations), the author first used an ordinary least squares model with clustered standard errors and found that married people reported higher life satisfaction before marriage, compared to people who remained single during the survey. This result supports a social selection perspective. Next, the author used a fixed effects regression model and found that the transition into marriage was associated with an initial rise and subsequent decline in life satisfaction. Life satisfaction increased after reaching its lowest level in the third year of marriage. Life satisfaction after the transition into marriage was significantly higher than that observed three or more years prior to marriage. The result supports a social causation perspective. Such changing patterns were not moderated by parental divorce during childhood. This study advances the current literature on marriage and life satisfaction by using a nationally representative longitudinal data set as well as by testing social selection and causation perspectives.

Experimental study on modified low liquid limit silt for abutment backfill in bridge-embankment transition section

  • Shu-jian Wang;Yong Sun;Zhen-bao Li;Kai Xiao;Wei Cui
    • Geomechanics and Engineering
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    • v.32 no.6
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    • pp.601-613
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    • 2023
  • Low liquid limit silt, widely distributed in the middle and down reaches of Yellow River, has the disadvantages of poor grading, less clay content and poor colloidal activity. It is very easy to cause vehicle jumping at the bridge-embankment transition section when the low liquid limit silt used as the backfill at the abutment back. In this paper, a series of laboratory tests were carried out to study the physical and mechanical properties of the low liquid limit silt used as back filling. Ground granulated blast furnace slag (GGBFS) was excited by active MgO and hydrated lime to solidify silt as abutment backfill. The optimum ratio of firming agent and the compaction and mechanical properties of reinforced soil were revealed through compaction test and unconfined compressive strength (UCS) test. Scanning electron microscope (SEM) test was used to study the pore characteristics and hydration products of reinforced soil. 6% hydrated lime and alkali activated slag were used to solidify silt and fill the model of subgrade respectively. The pavement settlement regulation and soil internal stress-strain regulation of subgrade with different materials under uniformly distributed load were studied by model experiment. The effect of alkali activated slag curing agent on curing silt was verified. The research results can provide technical support for highway construction in silt area of the Yellow River alluvial plain.

An Analytical Switching-Dependent Timing Model for Multi-Coupled VLSI Interconnect lines (디커플링 방법을 이용한 RC-Coupled 배선의 해석적 지연시간 예측 모델)

  • Kim, Hyun-Sik;Eo, Yung-Seon;Shim, Jong-In
    • Proceedings of the IEEK Conference
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    • 2004.06b
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    • pp.439-442
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    • 2004
  • Timing delays due to VLSI circuit interconnects strongly depend on neighbor line switching patterns as well as input transition time. Considering both the input transition and input switching pattern, a new analytical timing delay model is developed by using the decoupling technique of transfer multi-coupled lines into an effective single line. The analytical timing delay model can determine the timing delay of multi-coupled lines accurately as well as rapidly. It is verified by using DSM-Technology ($0.1{\mu}m$ /low-k copper-based process) that the model has excellent agreement with the results of SPICE simulation.

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Korea's Demographic Transition and Long-Term Growth Projection Based on an Overlapping Generations Model

  • KWON, KYOOHO
    • KDI Journal of Economic Policy
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    • v.39 no.2
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    • pp.25-51
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    • 2017
  • This paper employs an Overlapping Generations Model to quantify the impacts of Korea's demographic transition toward an older population on the total output growth rate. The model incorporates the projected population through 2060 according by Statistics Korea. The effects of the low fertility and increased life expectancy rates are studied. The model is considered suitable for analyzing the effects of demographic changes on the Korean economy. Under the assumption that the TFP growth rate will not slow considerably in the future, remaining at 1.3% per annum, the gross output growth rate of the Korean economy is projected to slow to 1.1% per annum in the 2050s, from 4.0% in the 2000s. The shrinking workforce due to the decline in fertility plays a significant role in the deceleration of the Korean economy. The increased life expectancy rate is expected to mitigate the negative effect, but the magnitude of its effect is found to be limited.

The Impact of Information Systems Integration on Organization

  • Juhn, Sung-Hyun
    • Asia pacific journal of information systems
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    • v.7 no.2
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    • pp.225-266
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    • 1997
  • A Causal Transition Model of the IT impact on organization is proposed. The model is based upon the premise that the IT impact is a multi-phase, multi-realm phenomenon, and that the IT impact in one organizational realm logically transpires to another realm, thus forming complex causal webs among them. Two exploratory research studies, the one qualitative and the other quantitative, were conductea to validate the model in a setting involving major structural reorganization of the organizations' IT function. The research results provide support for the general theory structure of the model. The findings include: ⅰ) the IT impact manifests on multiple organizational realms, with different degrees of strength, ⅱ) the impact on the realms follow a particular causal transition path among them, and ⅲ) the IT impact manifests on and through the information processing aspect of work. The results, however, indicate that people's perception of the IT impact is strongly mitigated by the IT relevance of work, and that the organization is affected as much by the structural arrangement surrounding and accompanying the IT as by the technology itself, suggesting that the IT impact is an organizational phenomenon as well as a technological phenomenon. The implications of the research results are discussed at the end.

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