• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3660-3665
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• 2012

For blind equalization, it is necessary to open an eye pattern quickly in the early stage of equalization, after that it is important to lower an error level of equalizer output signal. This paper discusses coarse error estimation using signal points specifically determined and fine error estimation using original signal constellation, and proposes two suggestions for how to take advantage of the two error estimation methods. The two error estimates, respectively, are effective to quickly open an eye pattern in the state of eye pattern closed, or to lower the level of an error in the steady-state after the eye pattern opening. Two blind equalization algorithms are proposed and their performances are compared, which select one of the two error estimates depending on the state of convergence of the equalizer, or combine two errors weightedly according to the relative reliabilities of the two error estimates, and calculate the new error.

• Phonetics and Speech Sciences
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• v.1 no.2
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• pp.163-171
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• 2009

This study attempted to investigate vocal characteristics and differences in gender and voice classification among classical singers. Twenty-three female singers (M = 23.1 yrs, SD = 3.6 yrs, average 6.3 yrs singing experience, all classified as sopranos) and twenty male singers (M = 25.2 yrs, SD= 3.6 yrs, average 6. 3 yrs singing experience, 8 tenors, 12 baritones) were recruited to participate in the present study. Speaking fundamental frequency (FO), closed quotient (CQ), MPT (Maximum Phonation Time), breathing types, maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), and singers' formants were measured. In addition, vibratory patterns were observed using stroboscopy. Sfo, singing CQ, breathing types, formant frequency in singers' formants, MIP, MEP, and MPT were significantly different from gender to gender. Generally, singers' formants were observed in male singers and also the pattern of singers' formants was different between tenors and baritones. Lower singing CQ values were observed than speaking CQ values in the female singers (P<.001). Furthermore, MEP, MIP, and singing CQ were significantly lower for female singers than for males singers (P<.001). MPT and speaking FO, however, were not significantly different between tenors and baritones.

• Journal of the Korean Society of Visualization
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• v.17 no.3
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• pp.52-58
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• 2019

Thermal performance and flow patterns inside the closed loop pulsating heat pipe (CLPHP) were experimentally investigated. For investigating the effect of working fluids, CLPHP was filled with various working fluids including methanol, acetone and ethanol. The thermal resistance was calculated by temperatures in evaporator and condenser and flow patterns were visualized by a digital camera. The thermal resistances for all fluids were decreased as the heat increases. Flow patterns change from static slug to elongated slug flows, bulk circulation and annular flows as the heat increases. Dry-out occurs after annular flows. For reasonable comparison of thermal performances, normalized CHF, Kutateladze number (K_u), was compared. Even though ethanol has smallest CHF, K_u of ethanol is similar with that of methanol. In addition, acetone has the highest K_u that means CLPHP with acetone provides the higher thermal performance compared with CLPHP with other fluids.

• Journal of the Korean Solar Energy Society
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• v.22 no.2
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• pp.39-47
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• 2002

The thermosyphon SDHWS and the loop type thermosyphon systems are widely used for domestic hot water system. The loop type thermosyphon is a circulation device for transferring the heat produced at the evaporator to the condenser area in the loop. In this study, the operating characteristics of various working fluids being used have been identified. The working fluids employed in the study were ethanol. water, and a binary mixture of ethanol and water. The volume of working fluid used in this study were 30%, 40%, 50%, 60% and 70% of evaporator volume. It is observed that, in the thermosyphon with low volume of working fluid, such as 30% or 40%, the fluid was dried out. The flow pattern and mechanism of the heat transfer were identified through this study. Flow patterns of the binary mixture working fluid were also investigated, and the patterns were recorded in the camera. The system parameters were calculated using the thermal performance data. Modelling of the system was carried out using PSTAR method and TRNSYS program.

• Geomechanics and Engineering
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• v.35 no.4
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• pp.333-366
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• 2023

Rock as a mass generally exhibits discontinuities, commonly witnessed in rock slopes and underground structures like tunnels, rock pillars etc. When these discontinuities experiences loading, a new crack emerges from them which later propagates to a macro scale level of failure. The failure pattern is often influenced by the nature of discontinuity, geometry and loading conditions. The study of crack growth in rocks, namely its initiation and propagation, plays an important role in defining the true strength of rock and corresponding failure patterns. Many researchers have considered the length of the discontinuity to be fully persistent on rock or rock-like specimens by both experimental and numerical methods. However, only during recent decades, there has been a substantial growth in research interest with non-persistent discontinuities where the crack growth and its propagation phenomenon were found to be much more complex than persistent ones. The non-persistence fractures surface is generally considered to be open and closed. Compared to open flaws, there is a difference in crack growth behaviour in closed or narrow flaws due to the effect of surface closure between them. The present paper reviews the literature that has contributed towards studying the crack growth behaviour and its failure characteristics on both open and narrow flaws subjected to uniaxial and biaxial compression loading conditions.

• Journal of Oral Medicine and Pain
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• v.16 no.1
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• pp.113-120
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• 1991

The authors examined the patterns and various ranges of mandibular movements in TMJ lock closed patients in the frontal, sagittal and horizontal plane pre-end post-treatment. And the author obtained the following results. 1. In the frontal plane, the patterns and ranges of mandibular movement of the patients were very irregular and small before treatment. But after the treatment, the patterns were similar to the typical shield shape of the normal subjects. And the velocity of opening and closing was improved after the treatment. 2. In the sagittal plane, the mean amount of maximum mouth opening was 27.0±4.0mm before treatment and 44.0±5.4mm after treatment. And there was statistically significant improvement(p<0.005). The patterns of the movement were very irregular and small before treatment, but were similar to the shape of "Posselt's envelope of motion" after the treatment. The velocity of opening and closing was improved after the treatment 3. In the horizontal plane, the mean amount of maximum laterotrusion was 8l2±2.5mm in the affected side and 6.7±2.2mm in the non-affected side before treatment. There was a significant difference between the sides(p<0.05). After the treatment, the mean was 10.4±2.6mm in the affected side and 8.9±2.3mm in the non-affected side and there was no significant difference between the sides(p>0.05). There was no significant difference in the mean amount of maximum protrusion between the before and aftertreatment(p>0.05), but the patterns of the movements were improved.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.63-67
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• 2012

Purpose: Lipogranuloma is the reaction of adipose tissue to various oils, paraffin, and other hydrocarbons injected into subcutaneous tissue for cosmetic or other reasons. The authors experienced a case of sclerosing lipogranuloma on the nasal dorsum. Methods: A 42-year-old female, without a history of the injection of any foreign materials, was admitted on our hospital for a painless, irregular, and firm mass located on her nasal dorsum with step-off deformity. It was considered that the mass had developed after augmentation rhinoplasty. The size of mass had been increased after closed reduction of nasal bone fracture. On April 2011, under general anesthesia, the mass was removed by open rhinoplasty technique. In addition, a pathologic examination was performed. After the mass extirpation, dermofat graft was performed for the correction of depression deformity. Results: The histopathological findings demonstrated a Swiss cheese pattern with variably-sized vacuoles, which corresponded to lipid removed with tissue processing, and variable foreign body giant cell reaction, fat necrosis, and hyalinized fibrous tissue. The pathologic diagnosis is lipogranuloma replacing nasalis muscle. It has been considered that sclerosing lipogranuloma is caused by nerve injury during augmentation rhinoplasty and the ointment used after the closed reduction of nasal bone fracture, which infiltrated through the injured mucosa. Conclusion: During the treatment of rhinoplasty or nasal bone fracture, the nerve injury or the ointment use can lead to lipogranuloma. Therefore, careful dissection for avoidance of the nerve injury and limited use of ointment seems to be helpful in decreasing incidence of lipogranuloma.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.476-483
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• 2017

The decay heat that is produced by nuclear reactor spent fuel must be cooled in a spent fuel storage pool. A wickless heat pipe or a vertical two-phase closed thermosyphon (TPCT) is used to remove this decay heat. The objective of this research is to investigate the thermal performance of a prototype model for a large-scale vertical TPCT as a passive cooling system for a nuclear research reactor spent fuel storage pool. An experimental investigation and numerical simulation using RELAP5/MOD 3.2 were used to investigate the TPCT thermal performance. The effects of the initial pressure, filling ratio, and heat load were analyzed. Demineralized water was used as the TPCT working fluid. The cooled water was circulated in the water jacket as a cooling system. The experimental results show that the best thermal performance was obtained at a thermal resistance of $0.22^{\circ}C/W$, the lowest initial pressure, a filling ratio of 60%, and a high evaporator heat load. The simulation model that was experimentally validated showed a pattern and trend line similar to those of the experiment and can be used to predict the heat transfer phenomena of TPCT with varying inputs.

• Journal of Korean Academy of Nursing
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• v.40 no.1
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• pp.99-109
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• 2010

Purpose: The purpose of this study was to identify effective nurse interaction patterns with patients in the emergency department. Methods: For this study, video technology was used to record complete conversations between the nurse and patient. The participants were 28 nurses and 63 patients in the emergency department at one university hospital located in Seoul. The data were collected from November, 2002 to April, 2003. The video recordings were observed for 4 hr for each case and coded using an adapted version of Roter's Interaction Analysis System (RIAS). The data were analyzed using cluster analysis to identify the patterns of nurse-patient interaction. Results: Cluster analysis revealed 4 distinct nurse interaction patterns; 1) "closed" characterized by orientation and negative talk, 2) "positive" characterized by positive affective talk, 3) "informative and directing" characterized by task-focused behavior including data gathering, and giving information about medical condition and treatment, 4) "facilitative" characterized by balance of psychosocial and biomedical topics. Patient satisfaction was highest in the facilitative interaction pattern. Conclusion: The patient centered interaction pattern, balancing information exchange and psychosocial exchange are the most effective interactions in the emergency department, suggesting that effective interaction skill is a core clinical nursing intervention in acute care.

• The Journal of Korean Academic Society of Nursing Education
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• v.3 no.2
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• pp.214-225
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• 1997

Sleep is an inevitable part of human existence and a part of the dynamic quality of life. The purpose of this study is to explore sleep pattern changes and related factors of patients hospitalized. The participants are 158 patients hospitalized in one general hospital. The questionnaire was developed by modification of VSH sleep scale (1987). Open question was used for research of related factors. $SPSS/PC^+$ are utilized for data analysis. The results are as follows ; There is significant difference before and after admission in the sleep disturbance. There is retroverse significant difference before and after admission in the sleep effectiveness. There is no significant difference between two groups in the nap supplementation. The patients reported pain by reason of sleep latency and mid-sleep awakening and noise due to early awakening. The reasons for lack of sleep were pain and noise. The method for overcoming their sleep disturbance, most of the subjects waited with closed eyes, imaged by themselved and took medicate sleeping pills. Discomfort manifested in the case of insufficient steepness was fatigue, headache and aggressiveness.