• Lingua Humanitatis
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• v.7
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• pp.335-353
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• 2005

In recent years there has been much discussion about whether there is a critical, or sensitive period for language acquisition. Research on a critical period provides an excellent example around which we can organize a discussion of the behavioral and neural evidence. In this paper, the early history of critical periods and evidence for the existence of critical periods in various domains of human cognition and learning are reviewed. Followed by this overview, evidence for a critical period in both linguistic and non linguistic area are presented. The paper then provides some unresolved questions regarding a critical period in language acquisition and states what the outcome of this issues mean for an understanding of language acquisition. Finally the paper concludes with some educational implications of a critical period for practice.

• Journal of ILASS-Korea
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• v.4 no.1
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• pp.55-61
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• 1999

The first maximum point in the stability curve of liquid jet, i.e., the critical point is associated with the critical Reynolds number. This critical Reynolds number should be predicted by simple means. In this work, the critical Reynolds number in the stability curve of liquid jet are predicted using the empirical correlations and the experimental data reported in the literatures. The critical Reynolds number was found to be a function of the Ohnesorge number, nozzle lengh-to-diameter ratio, ambient Weber number and nozzle inlet type. An empirical correlation for the critical Reynolds number as a function of the Ohnesorge number and nozzle length-to-diameter ratio is newly proposed here. Although an empirical correlation proposed in this work may not be universal because of excluding the effects of ambient pressure and nozzle inlet type, it has reasonably agrees with the measured critical Reynolds number.

• The Journal of Korean Academic Society of Nursing Education
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• v.15 no.2
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• pp.166-174
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• 2009

Purpose: The purpose of this study was to examine self esteem, self efficacy and critical thinking disposition of college students. Method: A descriptive survey method was used in this study. Data were collected from May to August, 2008, from 486 college students. The survey sheet was composed of questions on self esteem, self efficacy, and critical thinking disposition. Result: The average score of self esteem, self efficacy, and critical thinking disposition was 2.99, 2.80, and 3.99 respectively. There were positive correlations between self esteem and critical thinking disposition, between self efficacy and critical thinking disposition, and between self esteem and self efficacy. Self esteem and self efficacy were significant predictors of critical thinking disposition. Conclusion: In order to help college students adopt to a rapidly changing society, the university should make efforts to develop a curriculum and program for improving self esteem, self efficacy and critical thinking disposition.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.167-173
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• 2003

For the measurement of mass flow rate at a wide range of operation conditions, it is required that the critical nozzle gas different diameters, since the mass flow rate through the critical nozzle depends on the nozzle supply conditions and the nozzle throat diameter. In the present study, both computational and experimental investigations are performed to explore the variable critical nozzle. Computational work using the 2-dimensional, axisymmetric, compressible Navier-Stokes equations are carried out to simulate the gas flow through variable critical nozzle. In experimnet, a cylinder with several different diameters is inserted into the critical nozzle to vary the nozzle throat diameter. Computational results are compared with the experimented ones. The computed results are in close agreement with experiment. It is found that the displacement and momentum thickness of variable critical nozzle are given as a function of Reynolds numbers. The discharge coefficient of the variable critical nozzle is predicted using an empirical equation.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.337-345
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• 2002

The present study addresses a computational result of unsteady gas flow through a critical nozzle. The axisymmetric, unsteady, compressible, Wavier-Stokes equations are solved using a finite volume method that makes use of the second order upwind scheme for spatial derivatives and the multi-stage Runge-Kutta integral scheme for time derivatives. The steady solutions of the governing equation system are validated with the previous experimental data to ensure that the present computational method is valid to predict the critical nozzle flows. In order to simulate the effects of back pressure fluctuations on the critical nozzle flows, an excited pressure oscillation with an amplitude and frequency is assumed downstream of the exit of the critical nozzle. The results obtained show that for low Reynolds numbers, the unsteady effects of the pressure fluctuations can propagate upstream of the throat of critical nozzle, and thus giving rise to the applicable fluctuations in mass flow rate through the critical nozzle, while for high Reynolds numbers, the pressure signals occurring at the exit of the critical nozzle do not propagate upstream beyond the nozzle throat. For very low Reynolds number, it is found that the sonic line near the throat of the critical nozzle remarkably fluctuateswith time, providing an important mechanism for pressure signals to propagate upstream of the nozzle throat, even in choked flow conditions. The present study is the first investigation to clarify the unsteady effects on the critical nozzle flows.

• Journal of the Korea Fashion and Costume Design Association
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• v.22 no.2
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• pp.87-103
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• 2020

This study investigates critical fashion and discusses its critical messages, as it challenges the existing system of the fashion industry. This study reviews the literature on critical art and critical design and analyzes exhibition catalogs, magazines, and websites related to critical fashion practices. Thereupon, this study assumes the two distinctive messages of critical fashion design: materiality and experience, and the redefinition of the ideal body. First, materiality and experience pursues a change in perceptions of clothing materials by way of deconstructing clothes and exposing the process of production. This type of critical fashion breaks away from the traditional sartorial conventions and articulates new structures and experiences through dematerialization. Second, the redefinition of the ideal human body attempts to subvert the stereotypes of ideal beauty and introduce a variety of beauty in the human body. This type of critical design reconstructs the human body through transformation, expansion, and deconstruction and is often liberated from the dichotomy of gender norms.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.131-134
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• 2002

Compressible gas flow through a convergent-divergent nozzle is choked at the nozzle throat under a certain critical pressure ratio, and then being no longer dependent on the pressure change in the downstream flow field. In practical, the flow field at the divergent part of the critical nozzle can affect the effective critical pressure ratio. In order to investigate details of flow field through a critical nozzle, the present study solves the axisymmetric, compressible, Wavier-Stokes equations. The diameter of the nozzle throat is D=8.26mm and the half angle of the diffuser is changed between $2^{\circ}\;and\;10^{\circ}$ Computational results are compared with the previous experimental ones. The results obtained show that the divergence angle is significantly influences the critical pressure ratio and the present computations predict the experimented discharge coefficient and critical pressure ratio with a good accuracy. It is also found that a nozzle with the half angle of $4^{\circ}$ nearly predicts the theoretical critical pressure ratio.

• Korean Journal of Adult Nursing
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• v.16 no.1
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• pp.156-165
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• 2004

Purpose: This descriptive - comparison study was conducted to investigate the critical thinking disposition of senior nursing students in three types of nursing program. Method: The convenience sample was drawn from 472 nursing students. Instruments used in this study were made California Critical Thinking Disposition Inventory developed by Facione & Facione (1994). Data was analyzed by descriptive statistics, t-test, ANOVA, Scheffe test with SAS 6.12 program. Result: 1. The total mean score of critical thinking disposition was 279.06. Inquisitiveness was the highest with an mean score 45.50, while systematicity was the lowest with mean score of 36.15. There was a statistically significant difference in critical thinking disposition(F=14.36, p=.00)according to senior nursing students in three types of nursing programs. 2. There was a statistically significant difference in critical thinking disposition(F=5.53, p=.00) according to age, marital status(t=-3.15, p=.00), religion(F=3.26, p=.02) and critical thinking course taken previously(t=3.10, p=.00). Conclusion: There was a statistically significant difference in critical thinking disposition(F=14.36, p=.00) according to senior nursing students in three types of nursing program. There was a statistically significant difference in Critical thinking disposition according to age, marital status, religion, logic, philosophy, critical thinking course.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.73-88
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• 2014

Various studies on the critical flow models for sub-cooled and/or saturated water were reviewed, especially on Fauske, Moody, and Henry for basic theoretical models; Zaloudek for insight into physical phenomena for a critical flow in an orifice type flow path; Sozzi & Sutherland for a critical flow test of saturated and sub-cooled water at high pressure for orifice and nozzles; and a Marviken test on a full-scale critical flow test. In addition, critical flow tests of sub-cooled water for the break simulators in integral effect test (IET) facilities were also investigated, and a hybrid concept using Moody's and Fauske's models was considered by the authors. In the comparison of the models for the selected test data, discussions of the effect of the diameters, predictions of the critical flow models, and design aspects of break simulator for SBLOCA scenarios in the IET facilities were presented. In the effect of diameter on the critical flow rate with respect to all dimensional scales, it was concluded that the effect of diameter was found irrespective of diameter sizes. In addition, the diameter effect on slip ratio affecting the critical flow rate was suggested. From a comparison of the critical flow models and selected test data, the Henry-Fauske model of the MARS-KS code was found to be the best model predicting the critical flow rate for the selected test data under study.

• Journal of Arbitration Studies
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• v.32 no.4
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• pp.103-141
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• 2022

Traditionally, schedule analysis in Korea has been used, mainly through the Critical Path Method, to evaluate the claim for extension of time and/or the amount of liquidated damages for delay. Critical path method, however, cannot identify the delay event and its impact occurred in non-critical path especially in multi facility projects. In multi facility projects that comprise several independent but related facilities or structures, each facility has its own facility critical path the duration of which will be impacted by facility specific critical delays. Thus, only through the non-critical delay analysis along with the critical delay analysis damages not attributable to contractors may be remedied in full. Because all the records and pictures can reveal what has actually happened in post contract review, only the retrospective analysis rather than the prospective analysis based on the assumptions can establish the cause and allocate the each parties' responsibilities appropriately.