• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.979-987
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• 2013

It is becoming increasingly difficult for colleges to recruit new students to their full capacity. The increase of the withdrawal rate drives these colleges into crisis yet little has been done about it, because students with great possibility to withdraw enter colleges and old measures to stop them from dropping out hardly work. This study attempts to grope new measures to prevent dropout from college. To do this, I investigated withdrawal rate by college admission types and suggested measures to reduce withdrawal rate by incorporating the results of the investigation into admission procedures. I also compared the different types of admission in students satisfaction with college life and withdrawal rate, and suggested the measures to alleviated withdrawal rate. I expect the suggestions made in this study would be used effectively to reduce the withdrawal in colleges.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.4
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• pp.291-299
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• 2000

Morphine or butorphanol was continuously infused into cerebroventricle (i.c.v.) with the rate of $26\;nmol/{\mu}l/h$ for 3 days, and the withdrawal from opioid was rendered 7 hrs after the stopping of infusion. The expression of physical dependence produced by these opioids was evaluated by measuring the naloxone-precipitated withdrawal signs. The withdrawal signs produced in animals dependent on butorphanol (kappa opioid receptor agonist) were similar to those of morphine (mu opioid receptor agonist). Besides the behavioral modifications, opioid withdrawal affected G protein expression in the central nervous system. The G-protein ${\alpha}-subunit$ has been implicated in opioid tolerance and withdrawal. The effects of continuous infusion of morphine or butorphanol on the modulation of G protein ${\alpha}-subunit$ mRNA were investigated by using in situ hybridization study. In situ hybridization showed that the levels of $G\;{\alpha}s$ and $G\;{\alpha}i$ were changed during opioid withdrawal. Specifically, the level of $G\;{\alpha}s$ mRNA was decreased in the cortex and cerebellar granule layer during the morphine and butorphanol withdrawal. The level of $G\;{\alpha}i$ mRNA was decreased in the dentate gyrus and cerebellar granule layer during the morphine withdrawal. However, the level of $G\;{\alpha}i$ mRNA was significantly elevated during the butorphanol withdrawal. These results suggest that region-specific changes of G protein ${\alpha}-subunit$ mRNA were involved in the withdrawal from morphine and butorphanol.

• Journal of Korean Academy of Nursing
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• v.39 no.2
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• pp.270-278
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• 2009

Purpose: This study was performed to find out the effects of lidocaine or 8.4% sodium bicarbonate mixed with rocuronium on mean arterial pressure, heart rate and withdrawal movement. Methods: Data collection was performed from December 15, 2006 through May 31, 2007. Seventy-five patients with American Society Anesthesiologist (ASA) physical status I & II, under general anesthesia, were randomly assigned to 1 of 3 groups: R group (RG) received rocuronium 0.6 mg/kg; RL group (RLG), rocuronium 0.6 mg/kg mixed with 2 mL of 2% lidocaine; RS group (RSG), rocuronium 0.6 mg/kg with the same volume of 8.4% sodium bicarbonate. Mean arterial pressure, heart rate and withdrawal movement were observed from its injection until 5 min after endotracheal intubation. Results: The incidence of withdrawal movement with its corresponding injections was 72%, 40% and 4% in RG, RLG and RSG, respectively (p<.001). Score of withdrawal movement was the lowest in RSG of all groups (p<.001). While mean arterial pressure (p=.011) in RSG decreased significantly, and heart rate (p=.003) in RG increased more with its injection than before induction of anesthesia. Conclusion: Administration of the equivalent volume of 8.4% sodium bicarbonate with rocuronium is more effective than that of lidocaine with rocuronium compared with rocuronium only, in preventing withdrawal movement and in stabilizing mean arterial pressure and heart rate.

• KSBB Journal
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• v.25 no.2
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• pp.187-192
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• 2010

We designed the optimal operational strategy in repeated fed-batch ethanol fermentation using Sacchromyces cerevisiae ATCC 24858 in views of ethanol yield, specific ethanol production rate, and ethanol productivity, when the aeration rate were controlled at 0.0 and 0.33 vvm. Coincidentally, the time intervals of withdrawal-fill of culture medium (24 and 36 h) were investigated. Ethanol yield and ethanol productivity when the aeration was carried out at 0.33 vvm were superior to those when the aeration was not carried out. Additionally, those parameters when the time interval of withdrawal-fill of culture medium was 24 h were superior to those when time interval of withdrawal-fill of culture medium was 36 h. The total ethanol production reached at the greatest value, 703.8 g-ethanol, when the aeration was carried out at 0.33 vvm and the time interval of withdrawal-fill of culture medium was 24 h. In this study, we verified experimentally the necessity of designing the operational strategy for increasing ethanol production in terms of aeration rate and time interval of withdrawal-fill of culture medium in the repeated fed-batch ethanol fermentation.

• Human Ecology Research
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• v.53 no.6
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• pp.667-675
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• 2015

This study investigated the moderating effects of the number of friends and quality of friendship on the associations between withdrawal and loneliness as well as withdrawal and social anxiety. The subjects were 678 of fifth and sixth grade primary school children recruited from a public school in Bucheon city. A peer nomination inventory was used to assess withdrawal. Children were given a classroom roster and asked to nominate three classmates who fit each description. Children reported the quality of their friendships using the Friendship Quality Scale. Each child was asked to indicate his or her one best friend and rate how accurately a sentence describe done of their best friends on the scale. In addition, children completed questionnaires to assess the loneliness and social anxiety. The results revealed that the association between withdrawal and loneliness was not significant for children who had the large number of friends and high quality friendship. The association between withdrawal and social anxiety was stronger for the children who had the lower levels of friendship quality. However, there was no moderating effect of the number of friends on the association between withdrawal and social anxiety. These results imply that the large number of friends and high quality friendships could be protective factors for children who are withdrawn.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1225-1232
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• 2023

The ¹⁸⁰W is the lightest isotope of Tungsten with small abundance ratio. It is slightly radioactive (α decay), with an extremely long half-life. Its separation is possible by non-conventional single withdrawal cascades. The ¹⁸⁰W is used in radioisotopes production and study of metals through gamma-ray spectroscopy. In this paper, single withdrawal cascade model is developed to evaluate multicomponent separation in non-conventional transient cascades, and available experimental results are used for validation. Numerical studies for separation of ¹⁸⁰W in a transient single withdrawal cascade are performed. Parameters affecting the separation and equilibrium time of cascade such as number of stages, cascade arrangements, feed location and flow rate for a fixed number of gas centrifuges (GC) are investigated. The Salp Swarm Algorithm (SSA) as a bio-inspired optimization algorithm is applied as a novel method to minimize the feed consumption to obtain desired concentration in the collection tank. Examining different cascade arrangements, it is observed in arrangements with more stages, the separation is further efficient. Based on the obtained results, with increasing feed flow rate, for fixed product concentration, the cascade equilibrium time decreases. Also, it is shown while the feed location is the farthest stage from the collection tank, the separation and cascade equilibrium time are well-organized. Finally, using SSA optimal parameters of the cascade is calculated, and optimal arrangement to produce 5 gr of ¹⁸⁰W with 90% concentration in the tank, is proposed.

• Clinical Endoscopy
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• v.55 no.3
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• pp.332-338
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• 2022

Continuous measurement of quality indicators (QIs) should be a routine part of colonoscopy, as a wide variation still exists in the performance and quality levels of colonoscopy in Korea. Among the many QIs of colonoscopy, the adenoma detection rate, average withdrawal time, bowel preparation adequacy, and cecal intubation rate should be monitored in daily clinical practice to improve the quality of the procedure. The adenoma detection rate is the best indicator of the quality of colonoscopy; however, it has many limitations for universal use in daily practice. With the development of natural language processing, the adenoma detection rate is expected to become more effective and useful. It is important that colonoscopists do not strictly and mechanically maintain an average withdrawal time of 6 minutes but instead perform careful colonoscopy to maximally expose the colonic mucosa with a withdrawal time of at least 6 minutes. To achieve adequate bowel preparation, documentation of bowel preparation with the Boston Bowel Preparation Scale (BBPS) should be a routine part of colonoscopy. When colonoscopists routinely followed the bowel preparation protocols, ≥85% of outpatient screening colonoscopies had a BBPS score of ≥6. In addition, the cecal intubation rate should be ≥95% of all screening colonoscopies. The first step in improving colonoscopy quality in Korea is to apply these key performance measurements in clinical practice.

• Computers and Concrete
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• v.2 no.2
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• pp.97-110
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• 2005

Rheological behaviour of fresh concrete is an important factor in controlling concrete quality. It is recognized that the measurement of the slump is not a sufficient test method to adequately characterize the rheology of fresh concrete. To further understand the slump measurement and its relationship to the rheological properties, an elasto-viscoplastic, 2-D axisymmetric finite element (FE) model is developed. The FE model employs the Bingham material model to simulate the flow of a slump test. An experimental program is carried out using the Slump Rate Machine (SLRM_II) to evaluate the finite element simulation results. The simulated slump-versus-time curves are found to be in good agreement with the measured data. A sensitivity study is performed to evaluate the effects of yield stress, plastic viscosity and cone withdrawal rate on the measured flow curve using the FE model. The results demonstrate that the computed yield stress compares well with reported experimental data. The flow behaviour is shown to be influenced by the yield stress, plastic viscosity and the cone withdrawal rate. Further, it is found that the value of the apparent plastic viscosity is different from the true viscosity, with the difference depending on the cone withdrawal rate. It is also confirmed that the value of the final slump is most influenced by the yield stress.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.825-832
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• 2009

A series of laboratory experiments has been performed to investigate the flow characteristics of 2-dimensional density currents induced by selective withdrawal, which is commonly suggested as a measure for removal of high turbid water from reservoirs. Saltwater has been used to simulate the density stratification over depth and PIV(Particel Image Velocimetry) for observing the velocity structure. Experimental conditions have been established according to Richardson number, which is the dimensionless number that expresses the ratio of potential to kinetic energy. From the experiments, the patterns of longitudinal decay of centerline axial velocity induced by the withdrawal have been distinguished from other experimental cases. The rate of longitudinal decay increase as the Richardson number increases. The variations of volumetric and momentum flux along the longitudinal axis have also shown to be dependent on Richardson number.

• Human Ecology Research
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• v.54 no.6
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• pp.565-574
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• 2016

This research examined the trajectories of peer rejection in preschool children. This study also investigated the gender differences in the intercept and slope of the trajectories for peer rejection along with the influences of aggression, withdrawal and language ability on the trajectories of peer rejection. A latent growth curve model investigated peer rejection in 3 to 5 year olds. Three hundred and thirteen 3-year-old children were recruited from five preschools and 14 daycare centers. The children's language ability was measured by a Wechsler Preschool and Primary Scale of intelligence verbal test and teachers completed measurements for aggression and withdrawal. A peer nomination inventory was used to assess peer rejection. Children were asked to nominate three classmates who they do not like to play with. The research findings showed that peer rejection decreased during the preschool years. Compared with girls, boys showed higher levels of peer rejection and a slower change rate of peer rejection. Girls who were aggressive showed high levels of peer rejection and a slow change rate of peer rejection. Moreover, girls who had a high levels language showed low levels of peer rejection and a slow change rate of peer rejection. These findings imply that language ability could be a protective factor of peer rejection for girls.