• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.4
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• pp.315-322
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• 2008

Valves in power plants are leaking internally by various damages including insertion of foreign objects on seat, seat crack, defects and fatigue crack of stem packing or welds etc. due to severe operating conditions such as high temperature and high pressure for extended period time. Acoustic emission(AE) technology should be applied in order to diagnose precisely and evaluate these valve internal leak. In this paper, results of studies which have accomplished in actual power plant are presented. We have analyzed background noise, AE signal level and frequency spectrum through laboratory tests on the basis of various actual conditions in power plant, and also have considered evaluation methods on the background noise, AE properties and the detectable minimum leak rate according to valve leak conditions through comparing with results of field tests in power plant. As a result of these studies, we conformed that evaluation of internal leak conditions including discrimination of leak or not, and the detectable minimum leak rate is possible, and also it is expected to contribute to safe operation and prevention of energy loss in power plants.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.605-611
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• 1999

Conventional methods for assessing remaining life of critical high temperature components in fossil power plants rely on nondestructive inspection practices and accompanying life analysis based on fracture mechanics By using these conventional methods. It has been difficult to perform uninterrupted in-service inspection for life prediction. Thus, efforts have been made for developing on-line remaining life monitoring systems employing information on the shape of structures, operating variables and material properties. In thus study, a software for on-line life monitoring system which performs real-time life evaluation of a high temperature system headers was developed. The software is capable of evaluating creep and fatigue life usage from the real-time stress data calculated by using temperatures/stress transfer Green functions derived in advance for the specific headers. The major benefits of the developed software life in determining future operating schedule, inspection interval, and replacement plan by monitoring real-time life usage based on prior operating history.

• Journal of Biomedical Engineering Research
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• v.24 no.6 s.81
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• pp.523-531
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• 2003

We developed a PC-based 8-channel electrical stimulation system for transcutaneous functional electrical stimulation (FES), and applied it to FES exercise and paraplegic walking. The PC program consists of four parts: a database, a stimulation pattern generator, a stimulus parameter converter, and an exercise program. The stimulation pattern can be arbitrarily generated and edited by using the mouse on the PC screen, and the resulting stimulus parameters arc extracted from the recruitment curves, and transmitted to the 8-channel stimulator through the serial port. The stimulator has nine microprocessors: one master and eight slaves, Each channel is controlled by the slave microprocessor, and is operated independently. Clinical application of the system to a paraplegic patient showed significant increase in the knee extensor torque, the fatigue resistance, and the leg circumference, The patient can now walk about 50 meters for more than 2 minutes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.599-609
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• 2016

This study aimed to review and summarize the trends in research pertaining to the compassion satisfaction of nurses in Korea and to make suggestions for future research. For this study, RISS, KISS, NDSL, and National assembly library databases were searched using the key words 'nurse' and 'compassion satisfaction' or 'professional quality of life' and 'nurse'. Eighteen papers on compassion satisfaction of nurses were reviewed. This was a non-experimental study (100%), and included hospital nurses (100%). The general characteristics of interest pertaining to compassion satisfaction were age, position, career, educational status, and etc. The variables with respect to compassion satisfaction were burn out, compassion fatigue, job satisfaction, resilience, and etc. The findings of this study provide preliminary data on research trends in the compassion satisfaction of nurses. Nursing managers need to maximize strategies to enhance compassion satisfaction of nurses. A qualitative study and a development of a program focused on compassion satisfaction are recommended for future research.

• Journal of Korea Multimedia Society
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• v.16 no.1
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• pp.42-49
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• 2013

The camera motion is accompanied with the translation and/or the rotation of objects in frames of a video sequence. An unnecessary rotation of objects declines the quality of the moving pictures and in addition is a primary cause of the viewers' fatigue. In this paper, a novel method for correcting rotated frames in video sequences is presented, where the modified Mojette transform is applied to the motion-compensated area in each frame. The Mojette transform is one of discrete Radon transforms, and is modified for correcting the rotated frames as follows. First, the bin values in the Mojette transform are determined by using pixels on the projection line and the interpolation of pixels adjacent to the line. Second, the bin values are calculated only at some area determined by the motion estimation between current and reference frames. Finally, only one bin at each projection is computed for reducing the amount of the calculation in the Mojette transform. Through the simulation carried out on various test video sequences, it is shown that the proposed scheme has good performance for correcting the rotation of frames in moving pictures.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.249-258
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• 2009

The purpose of this study is to identify the factors influencing the musculoskeletal discomfort and the physical region related symptoms. The outcome of the study uses KOSHA Code H-30-2003 which defines possible symptoms into different categories. Symptom I, ll showing the highest occurrence rate in shoulder and neck regions and most of Symptom III, IV come from back region. Analysis of the factors influencing the musculoskeletal discomfort vary in different parts of the body. In the neck region, the discomfort related to rest and the computer keyboard. Gender affects the magnitude of pain in the shoulder region. Wrist pain is related to the chairs being used and back discomfort is influenced by shoulder exercise and the degree of rest taken. Physical fatigue due to work affects all the regions mentioned above. Conclusively, office workers are prone to the musculoskeletal discomfort due to their work environment. To alleviate this problem, the workers need to be educated with proper long-term musculoskeletal related health programs and exercise program containing various stretching methods. In addition, the effort to improve the variables in this study would help to reduce the rate of musculoskeletal discomfort.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.6
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• pp.768-773
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• 2012

One of the main reasons for serious road accidents is driving while drowsy. For this reason, drowsiness detection and warning system for drivers has recently become a very important issue. Monitoring physiological signals provides the possibility of detecting features of drowsiness and fatigue of drivers. One of the effective signals is to measure electroencephalogram (EEG) signals and electrooculogram (EOG) signals. The aim of this study is to extract drowsiness-related features from a set of EEG signals and to classify the features into three states: alertness, drowsiness, sleepiness. This paper proposes a drowsiness detection system using Linear Predictive Coding (LPC) coefficients and Support Vector Machine (SVM). Samples of EEG data from each predefined state were used to train the SVM program by using the proposed feature extraction algorithms. The trained SVM program was tested on unclassified EEG data and subsequently reviewed according to manual classification. The classification rate of the proposed system is over 96.5% for only very small number of samples (250ms, 64 samples). Therefore, it can be applied to real driving incident situation that can occur for a split second.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.697-700
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• 2004

The SBT$(Sr_{0.8}Bi_{2.4}Ta_2O_9)$ thin films for semiconductor device were deposited on Pt-coated $Pt/TiO_2/SiO_2Si$ wafer by RF magnetron sputtering method at $400[^{\circ}C]$ and annealed at the temperature range from $600[^{\circ}C]$ to $850[^{\circ}C]$. The top electrodes(Pt) were deposited on SBT thin film by DC sputtering method. The crystallinity of SBT thin films were increased with increase of annealing temperature in the temperature range of $600[{\circ}C]\sim850[^{\circ}C]$. The annealing temperature properties were to be most excellent in the case of annealed SBT thin film at $750^{\circ}C]$. And, the maximum remanent polarization$(2P_r)$ and the coercive electric field$(E_c)$ at annealing temperature of $750[^{\circ}C]$ obtained about $11.60[{\mu}C/cm^2]$ and 48[kV/cm], respectively. Specially, it was seen that fatigue properties does not change in $10^{10}$ switching cycle.

• 모자간호학회지
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• v.1
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• pp.16-22
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• 1991

Various minor discomforts are reported to be complained by the pregnant women. but what were and how much were they complained has not been revealed until recently. So, These lack of knowledge have given nurses difficulties in planning of care to promote the health during the pregnancy. Objectives of this study were to identify the rate of complaints in each minor discomforts and to explore the influencing factor on reduction of complaints of minor discomforts. The subjects were 120 mothers, who delivered their babies in hospital, from September to December 1990 and the reason why the postpartum mothers were selected as the subjects were minor discomforts could develope during the entire period of pregnancy. Data were gathered by the questionnares and analized statistically using SAS and SPSS program. Results were as follows. 1. More than one third of the subjects complained frequent urination, fatigue, increase of the vaginal discharge, morning sickness, the increased urination at night, pain in leg, backache, edema in leg, constipation, dyspnea, varicose vein, flatulence, headache. 2. Minor discomforts complained to be severe in more than one third of the subjects were frequent urination and increased urination at night. 3. The influencing factor to reduce the complaints of minor discomfort was revealed to be the perceived family support (r=0.030431, t=0.0007). We suggest that nurses should emphasize the importance of the family support to the pregnant women and their family, and to explore the relationships among the locus of control, the perceived family support and the complaints of minor discomforts.

• Women's Health Nursing
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• v.4 no.3
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• pp.332-347
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• 1998

This study was performed for the purpose of analyzing the relationship of menopausal symptoms of midlife women between urban area and rural area. A total of 129 midlife women who have lived in seoul, Kyeung ki and Kangwon were selected conveniently and data were collected by structured questionnaire from May to June, 1998. The instruments were the menopausal symptoms scale developed by Neugarten, Ci Sung-Ai & Kim Hy-Eun. Data analysis was done by Chi-square test, ANOVA, t-test. The results of this study were summarized as follows ; 1. The mean score for the menopausal symptoms of midlife women was 2.12. Serious menopausal symptoms which could be found in this study were "joint pain and numbness of arm and leg"(2.63), "fatigue and powerlessness"(2.58), "nervousness"(2.44). Over 97.8% of women complained menopausal symptoms. 2. In the relationship between social demographic variables and menopausal symptoms of midlife women were significant difference in urban area and rural area(t=-4.569, P=.000), marriage status(F=4.809, P=.010), education(F=7.359, P=.000), married son and daughter(F=7.359, P=.000), mensturational status(F=5.993, P=.003), and satisfaction to husband(F=9.093, P=.000). 3. In the relationship of menopausal symptoms of midlife women between two groups were statistically significant differences(t=-4.569, P=.000). The mean score of menopausal symptoms of rural women(2.34) were higher than those of urban women(1.85). This study shows the possible implication for nursing intervention of midlife women's health to prevent and relieve menopausal symptoms.