• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.3
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• pp.59-67
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• 2008

Due to the fast increase in cellular phone users, public interest on health effect of electromagnetic fields(EMFs) by cellular phonos is gradually increasing. Some EHS(electromagnetic hypersensitivity) patients complain of psycho-neurophysiological symptoms such as headaches, insomnia, memory loss resulting from RF radiation by CDMA cellular phones. However, EHS is difficult to diagnose and depends on the individual's subjective judgement. And we don't know clearly if the cause of EHS is uneasiness or real exposure. There have been various EHS volunteer studies on heart rate, blood pressure and subjective symptoms using GSM phones. But there are few studies on experimental case-control study investigating physiological parameters, subjective symptoms, and perception of EMFs. In this study, two volunteer groups of 17 self-declared EHS and 19 controls were exposed to both sham and real RF exposure by CDMA cellular phones for half an hour each. We investigated not only the physiological parameters such as heart rates, respiration rates and HRVs(hear rate variability), but also the perception of EMFs and subjective symptoms. As the results, EMF exposure did not have any effects on the subjective symptoms or physiological parameters for both groups. For the EMF perception, there was no evidence that EHS group perceived the EMFs correctly than the control group.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.6
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• pp.485-494
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• 2013

This paper deals with experimental evaluation methods for high speed judder on the brake-caliper system. Firstly, two types of brake caliper systems due to the wheel vibration was evaluated. Secondly, the high-speed judder of the brake was also investigated using the subjective rating evaluation in the high-speed road test. These experimental evaluations were carried out by changing the materials of brake pad and the specifications of the brake-corner module. Based upon the test results, a new specification of the brake pad, $15{\times}5$ vertical chamfer, was proposed. The new brake pad showed 3 points, 60 %, improvement in the subjective-rating evaluation comparing with conventional one. Besides, we need to decide properly with judder characteristic of pad material and have to carefully take into consideration other design parameters; caliper, disc, and the braking performance, durability, squeal noise.

• Journal of Acupuncture Research
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• v.18 no.3
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• pp.48-55
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• 2001

Objective : The main cause of back pain & sciatica is HNP of L-spine. Recently, 8 Constitution Acupuncture is largely used for it, but the effects isn't announced. So we studied. The perceived pain diminishment is compared with Body acupuncture and 8 Constitution acupuncture. Methods : VAS(Visual analogue scale) was used for this research, with the pain indicator of 10 and 0 which represents a patient admission to a hospital and a status of no pain respectively. Two groups, consisting of Body acupuncture group with 17 persons and 8 Constitution acupuncture group with 12 persons, was randomly allocated for this research. SPSS(Statistical Program for Social Science) for window is used for a statistical analysis, and the independent T-test is performed to gauge the improvement of VAS, in which case, value of P below 0.05 is considered as useful. Results : The result of the VAS of comparison analysis between two groups after 10 days, shows that the improvement of subjective symptoms in Body acupuncture group is more effective than that in 8 Constitution acupuncture group. (independent T-test, P=0.009)

• Journal of KSNVE
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• v.9 no.4
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• pp.841-848
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• 1999

In the quality assurance check process of DC motor systems, even though the overall sound pressure level is acceptable, there is an incident that subjective evaluation leads to failure in product quality due to annoying noise. This kind of problem may be originated from the manufacturing or assembly process. In this paper, the transient spectral analysis, or the time-frequency analysis is applied to the noise quality problem. For the case study, the cause of annoying noise in the wind shield wiper motor is experimentally analyzed in detail. It is concluded that the defect in the shaft causes the impact noise which is not detectable by steady spectral analysis. Also demonstrated is how the time-frequency analysis is effectively applied to the annoying noise identification of the rotor-gear system.

• Journal of Nutrition and Health
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• v.36 no.7
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• pp.749-758
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• 2003

Malnutrition is a common problem in patients undergoing maintenance hemodialysis (HD) and compromised food intake is an important cause. Malnutrition is one of the important factors influencing mortality in these patients. This study was conducted to evaluate the effectiveness of nutrition education at improving nutritional status of 23 Korean HD patients (mean : 48.6 $\pm$ 10.4 years, men : 8, women : 15). Anthropometric indices, nutrient intakes, and biochemical blood indices were measured before and after a 6-month nutrition education intervention. Anthropometric indices such as percent ideal body weight [PIBW (%)], body fat, body mass index (BMI), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), and calculated arm muscle area (CAMA) of subjects were within the normal range and not changed by nutrition education. Subjective global assessment (SGA) was significantly increased (p < 0.05) after nutrition education. Intake of total energy, carbohydrate, lipid, Ca, and vitamin B1 was increased significantly (p < 0.05) but intake of phosphorus, potassium, and sodium was decreased (p < 0.05). The serum concentrations of albumin, total protein, and Ca were significantly increased (p < 0.05), but levels of P and K were decreased (p < 0.05) after the intervention. These findings suggest that nutrition education for HD patients can be effective for positively changing nutrient intakes, leading to improvements in blood indices and nutritional status.

• Journal of East-West Nursing Research
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• v.23 no.2
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• pp.97-106
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• 2017

Purpose: The purpose of this study is to identify the factors influencing the happiness according to gender of the elderly living alone. Methods: This cross-sectional study used the raw data from the 2015 Community Health Survey. The subjects of this study were 14,705 elderly people aged 65 years or older, of which 2,198 were male elderly and 12,507 were female elderly. Results: The factors influencing the happiness of both male and female elderly were household income, depression, subjective stress level, subjective health level, quality of life, and lack of required medical service experience (p<.05). In addition, the male elderly were affected by the age, and the female elderly were affected by education, sleep time, walking and breakfast practice, and health screening (p<.05). Conclusions: It is necessary to develop and apply programs that can reduce the stress to increase the happiness of the elderly living alone, and efforts should be made not to cause a blind spot in terms of the health and welfare of the elderly living alone.

• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.37-45
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• 2013

Objective: This study describes the change of operator performance in drastic change of illumination level, and proposes an alternative method to cope with it. Background: The control standard of illumination for nuclear power plants(NPPs) is based on the set of limit criteria for maintaining a specific illumination level. However, there is a possibility to cause human errors according to the psychological and physiological influences to operators in the situation of drastic change of illumination such as SBO(Station Black Out), so a basic study is necessary to review the current approach. Method: We assessed the visual fatigue, subjective work load and task performance according to the three illumination situations(Normal Illumination, Emergency Illumination, and Drastic Change of Illumination). Result: Research finding shows that there are not significant differences in task performance between normal illumination (1,000lx level) and emergency illumination (100lx level), only if beyond the dark adaptation limit. However, subjective work load on mental demand and visual fatigue show a potential challenge to visual performance in drastic change of illumination. Conclusion/Application: Several trials can complement this challenge in NPPs by applying 3-way communication, enhancing readability of procedures, and managing the visual factors affecting the operators' performance through a Visual Environment Management Program including visual health aspects, etc.

• Journal of the Ergonomics Society of Korea
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• v.29 no.1
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• pp.139-144
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• 2010

Grape weeding work requires Ergonomics improvement, because it performs motion likely to cause Musculoskeletal disorders (MSDs) repeatedly and continuously. The object of this study was to reject workload in Grape weeding works raised MSDs with the Moving Rail-chair and Electromotive Scissors. As objective method of analysis, we used heart rate, EMG, RULA, REBA. As subjective method of analysis, we used questionnaire that indicate lethargy area of body, pain of muscle and bone. As a result, working with Moving Rail-Chair and Electromotive Scissors is lower heart rate and EMG than typical working. Also for the subjective evaluation, reducing of neck and shoulder movement makes improve workload.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.61 no.12
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• pp.669-673
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• 2018

Background and Objectives Tinnitus, a common complaint of workers who are exposed to noise, can cause substantial negative effects on the quality of life of these workers. The aim of this study was to analyze the characteristics of tinnitus in patients with noise-induced hearing loss and the relationship between tinnitus and the duration of noise exposure. Subjects and Method Thirty-three patients with subjective tinnitus and noise-induced hearing loss were included in this study. Tinnitus questionnaire, Tinnitus Handicap Inventory (THI) and audiological examinations were investigated according to the duration of noise exposure. Results There was a significant correlation between the tinnitus loudness and the duration of noise exposure. Patients who had longer periods of noise exposure had a louder tinnitus and higher THI score. However, there is no significant correlation between the characteristics of tinnitus and aging process. Conclusion The duration of noise exposure influences the loudness and distress of tinnitus. An awareness of tinnitus should be considered as part of hearing conservation program.

• 한국노년학
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• v.31 no.4
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• pp.1015-1027
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• 2011

The aim of this study is to understand the types of subjective causal perception of Hwa-byung among the Korean elderly men and reveal the characteristics of each type. Q-methodology was used to analyze each individual participant's subjectivity on Hwa-byung. A total of 25 Korean elderly men arranger 31 pre-selected Q-statement cards on a 9-point scale, shaping the cards' pile into a normal distribution. Then, the data from the arranged cards were analyzed using the QUANL PC Program. Data analysis showed that participants perceived four situation to cause Hwa-byung: Lack of sympathetic relationships, Incompetence and misfortune of their own, Weakness due to aging, and Regrets about the past to life. The analysis of the different types will be able to provide material on how to specifically offer psychological support to the Korean elderly men.