• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.16 no.4
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• pp.24-30
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• 2020

Ground source heat pump (GSHP) systems are actively introduced as cooling and heating conditioning systems of buildings due to annual stable performance and easily maintenance. However, ground temperature imbalance is occurred when the GSHP is used for a long period. Therefore, in this study, we proposed the operation method of the system that considered the recovery time of heat source temperature. The entering water temperature (EWT) and heat exchange rate (HER) were comparatively analyzed according to the continuous and intermittent operation. Furthermore, the underground thermal environment was evaluated by numerical analysis model. As the result, the intermittent operation was a maximum of 12.3% higher HER during the heating period than the continuous operation. In addition, the overall ground heat source temperature at the intermittent operation was higher than it at the continuous operation.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.2
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• pp.87-96
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• 2020

In this paper we proposed the test design method of reliability growth management. First, we presented the process for establishing the reliability growth management test design considering the number of failures and the termination test time. Reliability growth analysis of continuous system was performed in accordance with the test design process presented. In case the reliability test result is not met with the reliability target value after more than three failures occurred, the required test times were analyzed that 1,725 hrs for one corrective action, 1,950 hrs for two corrective actions. If the number of failures is less than three, design a reliability demonstration test according to confidence level 80% and 90% was performed using RGA 11 Software. As a result, it is possible to establish the reliability growth management test design with sufficient use of available resources. The results of this study can be used when establishing a test design for assessment of reliability growth management of all continuous systems.

• Earthquakes and Structures
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• v.24 no.5
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• pp.333-343
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• 2023

Various seismic isolation and reduction devices have been applied to suppress the longitudinal vibration of continuous girder bridges. As representative devices, lead rubber bearing (LRB) and fluid viscous damper (FVD) might suffer from deterioration during the long-term service. This study aims to evaluate the impact of device deterioration on the seismic responses of continuous girder bridges and investigate the seismic behavior of deteriorated LRBs and FVDs. Seismic performance of a simplified bridge model was investigated, and the influence of device deterioration was evaluated by the coefficient of variation method. The contribution of LRB and FVD was assessed by the Sobol global sensitivity analysis method. Finally, the seismic behaviors of deteriorated LRBs and FVDs were discussed. The result shows that (i) the girder-pier relative displacement is the most sensitive to the changes in the deterioration level, (ii) the deterioration of FVD has a greater effect on the structural responses than that of LRB, (iii) FVD plays a major role in energy dissipation with a low degradation level while LRB is more essential in dissipating energy when suffering from high degradation level, (iv) the deteriorated devices are more likely to reach the ultimate state and thus be damaged.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.145-149
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• 2007

Shape of soybean sprouts affects their marketability. This study was carried out to understand the effects of pressure in both overspraying and underwatering cultivation methods on growth and morphological characteristics of soybean sprouts. Pressing treatments were done by continuous pressing by laying a plastic culture box over another with growing the sprouts, their alteration every day, or no pressing in overspraying method, and by continuous pressing, pressing after the 4th day cultivation with 30 kg steel case, or no pressing in underwatering method. The soybean (cv. Junjery) seeds were soaked in 2 ppm BA solution for 5 hours and then aerated for 3 hours immediately before 6 day culture. Lateral roots, hypocotyl and root lengths, hypocotyl diameters, fresh and dry weights were measured. Lateral roots per sprout were decreased with stronger pressing regardless of watering methods. In overspraying method, continuous pressing treatment resulted in shortest hypocotyl, but no and ones did the longest root. In underwatering method, however, no pressing one showed the longest hypocotyl but continuous pressing did the shortest hypocotyl. Regardless of watering methods, middle part of hypocotyl was more thickened with stronger pressing although hook diameters of the 3 treatments were not affected. In overspraying method. total fresh weight per sprout was the least in no pressing but the greatest in continuous pressing. In underwatering method, however, there was no significant difference between the treatments.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.204-208
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• 2006

This study is to describe continuous-flow analysis (CFA) for the determination of nitrate using hydrazine-copper in plant material and to test precision of this method compared with that of methods, which are RQflex method and salicylic acid method. Samples were leaves of watermelon, cucumber, melon and tomato. Nitrate values measured by the RQflex method were greater than those measured by CFA or salicylic acid method. The correlation of nitrate values between those measured by CFA and salicylic acid method was $R^2=0.9671$, and those measured by CFA between those measured by RQflex method was $R^2=0.9739$. Recovery rate of nitrate added to tissue extract by CFA method was $99.7{\pm}0.25%$.

• The Journal of the Acoustical Society of Korea
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• v.14 no.3
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• pp.97-104
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• 1995

This paper is a study on the recognition of continuous digits for the implementation of a voice dialing system, and proposes an method of speech recognition using syntactic analysis and One-Stage DP. In order to perform the speech recognition, first of all, we make DMS model by section division algorithm and let continuous digits data be recognized through the proposed One-Stage DP method using syntactic analysis. In this study, 7 continuous digits of 21 kinds which is pronounced by 8 male speakers two or three times, are used. The speaker dependent and speaker independent recognition are performed with the above data by way of the conventional One-Stage DP and the proposed One-Stage DP using syntactic analysis under the condition of laboratory environment. From the recognition experiments, it is shown that the proposed method was better than the established method. And, the recognition accuracy of speaker dependence and independence by the proposed One-Stage DP using syntactic analysis was about 91.7% and 89.7%.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.374-379
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• 1996

Background: Recently, improvements in drug administration technology have intensified interest in the treatment of postoperative pain. this has resulted in increased use of continuous intravenous infusion of opioid and epidural opioid as alternative to traditional intramuscular administration of opioid. The goal of this study, therefore, was to document the effects of pain control and side effects following continuous intravenous infusion of morphine or meperidine and intramuscular meperidine following cesarean section. Methods: The vital signs, pain score, oxygen saturation and side effects were compared in 150 patients receiving continuous intravenous infusion of morphine, 30 ${\mu}g/kg/hr$ (n=50, group 1); continuous intravenous infusion of meperidine, 150 ${\mu}g/kg/hr$ (n=50, group 2); or intramuscular meperidine, 50mg/every 6hrs (n=50, group 3). Results: VAS (Visual Analogue Scale) was significantly decreased after 30 minutes of administration in all three groups and was significantly lower at 1 hour, but higher at 6 hours in group 3 than two other groups. Severe desaturation episode, defined as $SpO_2$<90%, occurred in the group 3(0.2%). Moderate desaturation episodes, defined as $SpO_2$ 91~95%, occurred more in group 3 than in group 1 and 2 (17.4% vs. 10.4%, 8.2%). The incidence of side effects were similar among three groups. Conclusion: The continuous infusion of opioid was more effective and safe method of postoperative pain control than traditional intramuscular injection.

• The Korean Journal of Pain
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• v.11 no.2
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• pp.321-325
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• 1998

Most of the patients with pain resulting from advanced cancer need opioid for adequate analgesia. Various Methods of drug administration to control the pain have been developed. One of them, continuous administration of intravenous morphine is used for more effective pain control in the patient with severe pain that cannot be satisfactorily controlled by other Methods of morphine administration. But this is not a suitable method at home because of the possibility of serious infectious complications and the difficulty in managing intravenous access by untrained personnel. Continuous subcutaneous adminstration of drugs can not only overcome such disadvantages of continuous intravenous infusion but also get almost the same effect of pain control as continuous intravenous infusion, and allows opportunity to move freely and return home, improving quality of life. We used continuous subcutaneous morphine and metoclopramide in the patients with cancer pain via a portable PCA device, and accomplished satisfactory pain relief without significant side effect.

• Journal of the Korean Data and Information Science Society
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• v.28 no.6
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• pp.1547-1555
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• 2017

This paper studies Bayesian test of homogeneity in contingency tables made by discretizing a continuous variable. Sometimes when we are considering events of interest in small area setup, we can think of discretization approaches about the continuous variable. If we properly discretize the continuous variable, we can find invisible relationships between areas (groups) and a continuous variable of interest. The proper discretization of the continuous variable can support the alternative hypothesis of the homogeneity test in contingency tables even if the null hypothesis was not rejected through k-sample tests involving one-way ANOVA. In other words, the proportions of variables with a particular level can vary from group to group by the discretization. If we discretize the the continuous variable, it can be treated as an analysis of the contingency table. In this case, the chi-squared test is the most commonly employed method. However, further discretization gives rise to more cells in the table. As a result, the count in the cells becomes smaller and the accuracy of the test becomes lower. To prevent this, we can consider the Bayesian approach and apply it to the setup of the homogeneity test.

• The Korean Nurse
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• v.34 no.2
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• pp.66-76
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• 1995

This study was done to identify burnout factors and coping methods surveyed upon 59 out-patients who have continuous peritoneal dialysis. Raw data was collected after being filled the questionnaire by subjects or directly interviewing at the peritoneal dialysis room of the K hospital. Taegu. Then. data was classified and analyzed according to categories of questions and revealed facts. The following results are obtained: The average age of subjects is 43.8 years old and the average duration of continuous peritoneal dialysis is 16.9 months. The reasons of choosing continuous peritoneal dialysis are 61. 0% by recommendation of doctor and nurse ranked as the first, 32. 2% by patient own decision ranked as the second. The 57.6% of subjects were experienced complications related to continuous peritoneal dialysis. The major psychosocial burnout factors because of the dialysis are confinement, wasting time, change in responsibility and role as a member of family, worriment for infection, interference in job: and the major physiological burnout factors are fatigue and weakness. Among the main coping methods, the problem-oriented coping methods are "accept the given situation itself, "actively try to change the situation", "try to maintain some controls over the situation", and the affective-oriented coping method are "give up and accept as fate", "pray", "ask comfort or help from family and friends", "sleep", "cry". Conclusively, it can be said that effective nursing intervention is needed to prevent continuous peritoneal dialysis burnout.