• ETRI Journal
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• v.39 no.3
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• pp.345-352
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• 2017

Traffic management is a highly beneficial mechanism for satisfying quality-of-service requirements and overcoming the resource scarcity problems in networks. This paper introduces an optimal connection admission control mechanism to decrease the packet loss ratio and end-to-end delay in cognitive radio sensor networks (CRSNs). This mechanism admits data flows based on the value of information sent by the sensor nodes, the network state, and the estimated required resources of the data flows. The number of required channels of each data flow is estimated using a proposed formula that is inspired by a graph coloring approach. The proposed admission control mechanism is formulated as a semi-Markov decision process and a linear programming problem is derived to obtain the optimal admission control policy for obtaining the maximum reward. Simulation results demonstrate that the proposed mechanism outperforms a recently proposed admission control mechanism in CRSNs.

• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.51-59
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• 1998

The vortex tube is a simple device for separating a compressed fluid stream into two flows of high and low temperature without any chemical reactions. Recently, vortex tube is widely used to local cooler of industrial equipments and air conditioner for special purpose. The phenomena of energy separation through the vortex tube were investigated to see the effects of cold flow inlet-outlet ratios and partial admission rates on the energy separation experimentally. The experiment was carried out with various cold flow inlet-outlet ratios from 0.28 to 10.56 and partial admission rates from 0.176 to 0.956 by varying input pressure and cold air flow ratio. To find best use in a given cold flow inlet-outlet ratio and partial admission rate, the maximum temperature difference of cold air was presented. The experimental results were indicated that there are an optimum range of cold flow inlet-outlet ratio for each partial admission rate and available partial admission rate.

• Journal of the Korea Society of Computer and Information
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• v.24 no.7
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• pp.117-123
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• 2019

In this paper, we propose to investigate the differences of academic achievement and core competence according to university admission types. Research subjects were 159 nursing students in G city. The tool used in this study was Collegiate Students Essential Skills Assessment developed by the KW University. The 6 areas measured with the tool are: humanities, Humanism, self-directedness, creative competence, practice competence and global competence. The data were analyzed by descriptive statistics, ANOVA, Scheffe' test and pearson's correlation coefficient using SPSS WIN 18.0 Program. There were significant differences in core competence according to university admission types. But There were significant differences in academic achievement according to university admission types. And significant positive correlation between academic achievement and core competece was not founded. But significant positive correlation of 6 core competencies were founded. Based on the result of this study, it is possible to serve basic data for establishing better university admission type.

• Clinical and Experimental Pediatrics
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• v.62 no.10
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• pp.386-394
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• 2019

Background: Preterm infants have difficulty maintaining body temperature after birth. However, clinical guidelines advocate that neonatal body temperature should be maintained at 36.5℃-37.5℃. Purpose: We aimed to investigate the incidence of admission hypothermia in very low birth weight (VLBW) infants and to determine the association of admission temperature with in-hospital mortality and morbidities. Methods: A cohort study using prospectively collected data involving 70 neonatal intensive care units (NICUs) that participate in the Korean Neonatal Network. From registered infants born between January 2013 and December 2015, 5,343 VLBW infants born at less than 33 weeks of gestation were reviewed. Results: The mean admission temperature was 36.1℃±0.6℃, with a range of 31.9℃ to 38.4℃. Approximately 74.1% of infants had an admission hypothermia of <36.5℃. Lower birth weight, intubation in the delivery room and Apgar score <7 at 5 minutes were significantly related to admission hypothermia. The mortality was the lowest at 36.5℃-37.5℃ and adjusted odd ratios for all deaths increased to 1.38 (95% confidence interval [CI], 1.04-1.83), 1.44 (95% CI, 1.05-1.97) and 1.86 (95% CI, 1.22-2.82) for infants with admission temperatures of 36.0℃-36.4℃, 35.0℃-35.9℃, and <35.0℃, respectively. Admission hypothermia was also associated with high likelihoods of bronchopulmonary dysplasia, pulmonary hypertension, proven sepsis, pulmonary hemorrhage, air-leak, seizure, grade 3 or higher intraventricular hemorrhage and advanced retinopathy of prematurity requiring laser therapy. Conclusion: A large portion of preterm infants in Korea had hypothermia at NICU admission, which was associated with high mortality and several important morbidities. More aggressive interventions aimed at reducing hypothermia are required in this high-risk population.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.562-573
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• 2016

Diversification of college admission system has recently brought up the problem of system fairness. Studies on fairness of college admission system mainly focused on policy proposal or investigation of teacher's perception. Different from previous works, this study aims to analyze college students' perceptions of fairness of the current college admission system. This study used grounded theory and interviews from eleven students. Results of analysis are as follows. Causal condition proved to be frequent change in admission system happened in the course of diversifying admission criteria. The core phenomenon is fundamental unfairness in both procedural and substantive aspects of admission system. Contextual condition is information and infrastructure asymmetry among students which has a root in regional gap in Korea. Mediatory condition is advance of information technology and individual or group effort to overcome disadvantages. In conclusion, students consider that unfairness in college admission system reflects social structural problems that cannot be solved in a one-time prescription.

• Journal of the Korean Data and Information Science Society
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• v.23 no.2
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• pp.343-351
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• 2012

We analyse the relations between the academic achievement and the university admission factors among the class of 2011 at A university classified by sex and entrance test type. We can provide helpful tools for the university entrance policy by finding the intimate admission factors with academic achievement. We found that the university admission factors had effects on the academic achievement differently according to sex and entrance test type. Female students and regular admission achieved more than male students and occasional admission, respectively. Korea scholastic aptitude test had more effects on academic achievement for male students and regular admission type NA but academic achievement in high school life had more effects for female students and regular admission type DA.

• Journal of The Korean Association of Information Education
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• v.15 no.3
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• pp.493-503
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• 2011

The Korea Ministry of Education, Science and Technology (MEST) determines admission quota of cyber universities. MEST's decision is made based on each university's physical and administrative capacity for handling admission numbers. However, the unique characteristics of cyber universities (e.g., online teaching and learning environments) are not considered in MEST's current decision process. MEST also lacks specifics in their policies that are required to ensure university's autonomous control for admission number as well as learners' rights and quality assurance. This study intended to improve decision making process on admission quota of cyber universities so as to increase quality assurance of education. The alternative admission quota decision frameworks have been formulated based on (a) the analysis of the current practices of cyber universities, (b) focus group interviews, and (c) recommendations of the expert.

• Physical Therapy Korea
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• v.17 no.3
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• pp.59-67
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• 2010

Mortality rates from stroke have been declining. Because of this, more people are living with residual disability. Rehabilitation plays an important role in functional recovery of stroke survivors. In stroke rehabilitation, early prediction of the obtainable level of functional recovery is desirable to deliver efficient care, set realistic goals, and provide appropriate discharge planning. The purpose of this study was to identify predictors of functional outcome after stroke using inpatient rehabilitation as measured by Functional Independence Measure (FIM) total scores. Correlation and stepwise multiple regression analyses were performed on data collected retrospectively from two-hundred thirty-five patients. More than moderate correlation was found between FIM total scores at the time of hospital admission and FIM total scores at the time of discharge from the hospital. Significant predictors of FIM at the time of discharge were FIM total scores at the time of hospital admission, age, and onset-admission interval. The equation was as follows: expected discharge FIM total score = $76.12+.62{\times}$(admission FIM total score)-$.38{\times}(age)-.15{\times}$(onset-admission interval). These findings suggest that FIM total scores at the time of hospital admission, age, and onset-admission interval are important determinants of functional outcome.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1738-1743
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• 2004

Turbo-pump system, an essential component of liquid rockets and induced weapons, adopts a partial admission axial turbine which drives pump. And the turbine of a turbo-pump system is usually operated at supersonic condition due to its high loading chracteristics. Therefore, reseaches about flow and performance characteristics of a partial admission supersonic turbine must be preceeded to progress the aerospace and defense industries as well as the development of turbo-pump systems. In this study, flow characterisitics within blades of the partial admission supersonic turbine are numerically investigated by using Fine Turbo, a commercial CFD Code. Before performing the numercial analyses, to verify accuracy of the numerical result computed by Fine Turbo, I performed the comparison between the numerical results with J.J.Cho' experimental results. It is found that the numerical results show good agreement with the experimental results. Computations about the partial admission supersonic turbine have been performed to investigate flow characteristics including shock patterns. It is also found that the flow and performance of partial admission supersonic turbine are largely depend on shocks ocurred in the nozzle and at the leading edge of blades, expansion or compression at exit of nozzle and separations occurred in passage.

• Acute and Critical Care
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• v.33 no.4
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• pp.230-237
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• 2018

Background: Socioeconomic status (SES) is closely associated with health outcomes, including mortality in critically ill patients admitted to intensive care unit (ICU). However, research regarding this issue is lacking, especially in countries where the National Health Insurance System is mainly responsible for health care. This study aimed to investigate how the SES of ICU patients in South Korea is associated with mortality. Methods: This was a retrospective observational study of adult patients aged ${\geq}20$ years admitted to ICU. Associations between SES-related factors recorded at the time of ICU admission and 30-day and 1-year mortalities were analyzed using univariable and multivariable Cox regression analyses. Results: A total of 6,008 patients were included. Of these, 394 (6.6%) died within 30 days of ICU admission, and 1,125 (18.7%) died within 1 year. Multivariable Cox regression analysis found no significant associations between 30-day mortality after ICU admission and SES factors (P>0.05). However, occupation was significantly associated with 1-year mortality after ICU admission. Conclusions: Our study shows that 30-day mortality after ICU admission is not associated with SES in the National Health Insurance coverage setting. However, occupation was associated with 1-year mortality after ICU admission.