• Journal of the Korean Society for Nondestructive Testing
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• v.18 no.5
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• pp.365-372
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• 1998

The method of measuring the nonlinear effect of ultrasonic waves is suggested as a new approach for the effective evaluation of material degradation. In sonic wave propagation, the existence of nonlinear effect can be demonstrated by the generation of higher order harmonic waves. So, at first, the mechanism of generating higher order harmonic components due to nonlinear effect was explained by using nonlinear elasticity. Next, we attempted to measure how much of the higher order harmonic component was generated in the degraded material. For this purpose, a measurement system mainly based on a high-powered nonlinear ultrasonic signal analysis system was constructed, and SS41 and SS45 specimen intentionally degraded by tensile load and fatigue load were tested. From the results, we confirmed that the measurement of nonlinear acoustic effect may be useful for the evaluation of material degradation.

• Journal of Welding and Joining
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• v.13 no.2
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• pp.12-24
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• 1995

Recently, more researches have been actively performed for the assessment of material degradation and residual-life of elevated temperature plant components, as some of domestic fossil power plants become older than 30 years. In this paper, results of on_site residual life assessment are reported for main steam pipes of Youngwol power station #2 which have operated since 1965. For critical weld locations such as butt welds branch welds, Y_sections and a T-section, replication technique and hardness measurement technique were employed for life_assessment. When cracks were detected by conventional NDT tests, crack growth life was calculated using a computer code. On the other hand, for matrix of pipes, residual life was quantitatively estimated by an analytic method and material degradation was estimated qualitatively using diameter measurement data and grain-boundary etching method. Also, direction in further improvement of on-site life assessment techniques are proposed.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.2
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• pp.149-154
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• 2012

The size and distribution of welding residual stress and welding deformation in welding structures have an effect on various sorts of damage like brittle failure, fatigue failure and stress corrosion cracking. So, research for this problem is necessary continuously. In this study, non-destructive technique using laser electronic speckle pattern interferometry, plate of welding specimen according to the external load on the entire behavior of residual stress are presented measurement techniques. Once, welding specimen force tensile loading, using electronic speckle pattern interferometry is measured. welding specimen of base metal and weld zone measure strain from measured result, this using measure elastic modulus. In this study, electronic speckle pattern interferometry use weld zone and base metal parts of the strain differences using were presented in residual stress calculated value, This residual stress value were calculated by numerical calculation. Consequently, weld zone of modulus high approximately 3.7 fold beside base metal and this measured approximately 8.46 MPa.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.527-535
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• 2001

Objectives : To improve decreased erectile function as well as impotence, caused by physical fatigue, psychologic stress, too much alcohol and smoking, medication like antihypertensives, and geriatric change, by the prescription of BOWONDAN. Methods : 18 male-volunteers with decreased erectile function who are married 30 to 59 years old, were studied about the difference of a sexual function between before and after taking BOWONDAN 3 pills a day for a month. The results of IIEF(International Index of Erectile Function) and AVSS(Audio-Visual Sexual Stimulation) were reviewed statistically with paired samples t-test. Results : Based on the IIEF, 13(81.25%, p<0.01), 9(56.25%, p<0.05), 9(56.25%, p<0.05), 9(56.25%, p<0.05), 7(43.75%, p<0.05) and 15(93.75%, p<0.01) volunteers were improved in erectile function, orgasmic function, sexual desire, intercourse satisfaction, overall satisfaction and total score respectively, among 16 volunteers excluding 2 due to a false measurement. Through the Rigiscan of AVSS, 11 (68.75%, p<0.1)volunteers were improved in base tumescence, among 16 volunteers excluding 2 due to a false measurement. Conclusions : As a result of our work, BOWONDAN is expected to take effect to treat or improve both impotence and decreased erectile function.

• Science of Emotion and Sensibility
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• v.5 no.4
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• pp.45-49
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• 2002

Recently, virtual environment systems are used in various application fields such as industry, medicine, and training and education. However, the negative effect, cybersickness including nausea, visual fatigue, and disorientation, could be happened while using VR systems. It prevents VR system from spreading much more. To control the cybersickness, first of all, the objective measurement method should be established. As one of alternative methods, the postural instability could be a measure of cybersickness. In this study, 45 participants' postural sway before and after experiencing a H driving simulator was measured by using a force platform. Especially, we examined if two factors, motion and feedback, could affect on the postural instability The results showed the postural instability slightly increased after experiencing the VR driving simulator. For the factors, the providing of motion synchronized to visual display showed statistical significant decrease in postural sway along lateral side. To check the effectiveness of postural instability as a cybersickness measure, further studies are needed.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.6
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• pp.496-503
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• 2016

Leakages at plant structures of power and petrochemistry plants have led to casualties and economic losses. These leakages are caused by fatigue failure of pipelines and their wall thickness. Vibration measurement methods for plant pipelines mainly use acceleration and laser sensors. These sensors are difficult to install and operate and thus lead to an increase in operational cost especially for wide area surveillance. Recently, measurements of leak and vibration displacements using cameras have attracted the interest of many researchers. This method has advantages such as simple installation, long distance monitoring, and wide area surveillance. Therefore, in this paper, we have developed a system that can measure the leakage and vibrational displacement by using a camera. Furthermore, the developed system was verified with experimental data.

• Journal of muscle and joint health
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• v.10 no.1
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• pp.44-53
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• 2003

Purpose : This study was to identify Korean terms appropriate for a new scale using pain terms to assess the pain of the arthritis patients. Method : This study was conducted by secondary analysis of two previous studies, one from Kim's data (1994) and the other from Lee and Choi's(1988). The subjects were 482 patients with arthralgia. Data were analyzed by SPSS Win 11.0, for frequencies, percentages, and means. Results : Five pain groups were sorted out from the sensory pain category, three in the affective pain category, and two in the miscellaneous pain category by selecting groups of pain terms expressed more than 50% by all subjects. Local inflammatory repeated pain terms, simple irritative pain terms, superficial pressure pain terms, traction pain terms, and peripheral nerve terms were included in the sensory pain category, fatigue-related pain terms, digestion-related terms, and suffering-related terms in the affective category, and dull pain terms and body cavity pressure pain category. Among five sample groups terms selected by more than 3 groups with more than 30% of patients were dugumhada, sikungorinda, wooksinwooksinhada, nurudusi apuda, and dangginda in the sensory pain category; nogonhage apuda, gobukhada, and jajungsurupge apuda in the affecte pain category; and buctjockgigunhada and manjimyon apuda in the miscellaneous pain category. Conclusion : Ten pain groups were tentatively selected out of 20 pain groups; 10 pain terms composed of 1 pain term from each group were selected out of 90 pain terms from thesecondarydataofarthriticpainpatients. Implications More detailed clinical studies are needed for the refinement of the scale.

• Journal of Korean Academy of Nursing
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• v.16 no.2
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• pp.13-28
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• 1986

The main purpose of th study was to evaluate he validity of Korean Pain Measurement Tool composed of pain terms. The specific purposes of this study were 1. to examine whether pain intensities of pain terms are congruent with those classified in three previous studies. 2. to evaluate the relative intensity of each term by panel of judges. 3. to explore the difference of ranks of pain terms according to the sex, education, and ages. One hundred and sixty normal individuals were selected by 2$\times$2$\times$4 sampling design. Sex (male, female), education (high school, college), and age (20s, 30s, 40s, 50s) were matched. Each individual was asked to rate the ranks of 3~8 pain terms in each subclass. The data measured by ordinal scale were transformed to the interval scale to compare with the pain intensities gained from the previous study. The pain ranks different from previous results were finally rearranged or cancelled through the consultation of 4 panel of judges and sunmed up to 91 pain terms in the scale. As a result, the ranks of pain terms within each of eleven subclasses among the twenty subclasses completely were congruent with the Previous pain ranks, while the ranks of nine subclasses were different from the previous pain ranks. In addition, there was significant relation between sex and pain ranks in skin punctuate pressure pain and cavity pressure. (sp : $\chi$$^2$=5.18 ø=0.26； cp : $\chi$$^2$=5.83 ø=0.24) In conclusion, seven terms from subclasses of inflammatory repeated pain, traction pressure pain, fatigue-related pain, fear-related pain, dull pain, and pulsation. related pain were cancelled. The ranks of four terms in subclasses of incisive Pressure pain and constrictive pressure pain were tentatively rearranged. Ranks of two terms in the tract pain were left as shown in the third study. As a result, six terms must be studied repeatedly for obtaining exact scores from ratio scale.

• Journal of Korean Biological Nursing Science
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• v.7 no.2
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• pp.31-48
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• 2005

Purpose: Studies focus on cancer control, prevention, or assessment of psychosocial problems and intervention methods. However, few studies exist concerning psychosocial problems, measuring tools for those problems, and interventions for cancer patients in Korea. One of the purposes of this study was to review studies in this area, to examine various psychosocial problems experienced by cancer patients. This is a crucial area to investigate, since psychosocial problems in turn negatively influence the patients' immune function, which speeds the progress of the disease. Another goal was to identify instruments used to measure psychosocial functioning and problems in cancer patients, to analyze their validity and reliability, with the aim to discover the best instruments. A final goal was to explore and compare the effects of psychosocial interventions, to determine the most effective practices. Method: Journal articles published since 1995 were searched from PubMed Data base, Google search engine, and published cancer-related studies, using search keywords "psychosocial function and intervention for the cancer patients"; whole articles of selected references were reviewed and analyzed. Result: Most common psychosocial problems were depression, fatigue, nausea, pain, distress, resulting in a low quality of life. The seven scales found in the literature to assess the psychosocial functioning were Center for Epidemiological Studies-Depression, State-Trait Anxiety Inventory, Symptom Checklist 90-R, Profile of Mood States, Psychosocial Adjustment to Illness Scale, Brief Symptom Inventory, and SF-36 HRQOL(Health Related Quality of Life). Social support interventions for cancer patients were effective in improving quality of life scores. Conclusion: It is necessary to apply support intervention strategies to help cancer patients in Korea. These strategies can help to reduce the effects of psychosocial symptoms, which in turn affect the development and control of cancer. Strategies developed in Western countries may need to be modified for use within Korea. Further studies are warranted to review the support intervention strategies that were being used to for cancer patients

• Journal of Auto-vehicle Safety Association
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• v.14 no.2
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• pp.57-69
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• 2022

Recently, as interest in self-driving cars has increased worldwide, research and development on the Advanced Driver Assist System is actively underway. Among them, the purpose of Adaptive Cruise Control (ACC) is to minimize the driver's driving fatigue through the control of the vehicle's longitudinal speed and relative distance. In this study, for the research of the ACC test in the real environment, the real-road test was conducted based on domestic-road test scenario proposed in preceding study, considering ISO 15622 test method. In this case, the distance measurement method using the dual camera was verified by comparing and analyzing the result of using the dual camera and the result of using the measurement equipment. As a result of the comparison, two results could be derived. First, the relative distance after stabilizing the ACC was compared. As a result of the comparison, it was found that the minimum error rate was 0.251% in the first test of scenario 8 and the maximum error rate was 4.202% in the third test of scenario 9. Second, the result of the same time was compared. As a result of the comparison, it was found that the minimum error rate was 0.000% in the second test of scenario 10 and the maximum error rate was 9.945% in the second test of scenario 1. However, the average error rate for all scenarios was within 3%. It was determined that the representative cause of the maximum error occurred in the dual camera installed in the test vehicle. There were problems such as shaking caused by road surface vibration and air resistance during driving, changes in ambient brightness, and the process of focusing the video. Accordingly, it was determined that the result of calculating the distance to the preceding vehicle in the image where the problem occurred was incorrect. In the development stage of ADAS such as ACC, it is judged that only dual cameras can reduce the cost burden according to the above derivation of test results.