• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1885-1887
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• 2000

In this paper we introduce preventative and diagnostic systems developed to prevent substations from accidental fault of electric power transmitting apparatus. We propose monitoring and diagnostic system for ultra high voltage GIS and main transformer of 765kV substations as an example of preventative and diagnostic techniques being applied in Korea. We also present a guideline to construct and manage an expert system for this purpose. Finally, an engineering solution as a substation management support system is proposed.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.359-360
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• 2008

765kV변전소의 운전 조건을 고려하여 유지보수(CBM) 기법을 활용한 예방진단시스템을 이용해 변전기기를 정비한 사례를 통하여 예방진단시스템의 운영실태를 살펴보고, 고장원인 및 고장설비를 더욱 정확히 구분할 수 있어 관계자에게 보다 신뢰성있는 시스템이 될 수 있도록 대안을 모색하며 향후 진단 및 감시항목을 더 발굴하기 위한 예방진단 시스템을 제도화 할 필요가 있다.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.275-277
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• 2001

In this paper a preventative and diagnostic system for high and ultra high voltage electric power transmission apparatus is proposed to secure substation normal operation. The proposed system consists of monitoring sub-system and diagnostic sub-system, which are mainly for GIS and main transformer, and the system will be applied for newly established 765kV class substation in Korea. Some guideline for combination with substation control system are presented, and engineering solution as an improved substation automation system is also proposed.

• Biomedical Science Letters
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• v.28 no.1
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• pp.1-8
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• 2022

Total joint arthroplasty is a successful joint replacement treatment that improves joint function and overall quality of life and provides pain relief. However, the prevalence of periprosthetic joint infection (PJI) has become prevalent with the rise in the incidence of arthroplasty surgery. PJI occurs rarely following arthroplasty however presents with serious complications, including high morbidity. The identification of causative microorganisms is essential for the treatment of PJI. Managing PJI requires complex treatment strategies, including long-term antibacterial treatment, and significant medical costs can be incurred. The American Academy of Orthopedic Surgeons, the Centers for Disease Control and Prevention, and Surgical Care Improvement Project guidelines recommend that prophylactic antibiotics such as first-generation cephalosporins be infused completely 1 hour before surgical incision. However, these preventative antibiotics are very limited, therefore risk factors must be identified to diagnosis and treat patients effectively. Moreover, determining antimicrobial susceptibility during artificial joint surgery and choosing the most appropriate treatment strategy following an accurate diagnosis of microbial infections are essential. In the present review, we describe the management, including the etiology, diagnosis, and classification of PJI, and approaches to its diagnosis using the available novel molecular diagnostic methods.

• Journal of the Ergonomics Society of Korea
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• v.22 no.4
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• pp.79-90
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• 2003

The purposes of this study are to compare data for work-related musculoskeletal disorders(WMSDs) between Korea and USA, and to investigate status of WMSDs for industrial safety managers. The first part of this study was based on statistical data annually published by Minister of Labor of Korea and Bureau of Labor Statistics of USA. The latter was performed by using questionnaire survey for industrial safety managers in two regions. The results showed that the WMSDs incidence rate was significantly lower in Korea than in USA, and that there is big difference in the distribution of occupational illness by category of illness between Korea and USA. The questionnaire survey revealed that knowledge level about WMSDs was significantly affected depending upon corresponding companies' location and size, and that the low back pain was the most prevalent illness among varying WMSDs symptoms, followed by tendonitis/tenosynovitis, carpal tunnel syndrome, and tennis elbow. Based on this study, it is recommended that the future education/training for WMSDs focus on their preventative measures, methods/tools for identifying their risk factors, and diagnostic criteria for judging suspicious symptoms for industrial accidents, and that the governmental policy for WMSDs be changed towards financial supporting for preventive facilities, establishing objective diagnostic criteria and training for WMSDs.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.3
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• pp.275-288
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• 2010

In order to improve the quality of electricity in large scale power systems, stability of power system has to be achieved. This can be done by the means of preventative diagnosis of power equipments and protection, monitoring and control of the power system. Since the recent adoption of digital controllers, an improvement in stability was observed; in particular, IED, which contained self-diagnostic abilities such as fault tolerance, allowed for automatic recovery via redundancy or switching-over functions should there be faults with the equipments. Furthermore, communication lines have been hugely simplified, thus adding to the improvement in stability significantly. Taking these error reports and forecasting emergency reports and by effectively responding to them in the overiding controlling systems, high levels of system stability can be obtained. Power Management System that is being applied to automated power sub-stations, takes the IEC61850 international standard as its specification. In this paper, additional research into achieving stability of already developed PMS system and also the stability of the overall system was carried out, and the results of development of communication servers, which play a pivotal role in connecting systems, are stated.

• Safety and Health at Work
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• v.6 no.2
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• pp.134-138
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• 2015

Background: Noise-induced hearing loss (NIHL) is a major preventable occupational health problem with 250 million people worldwide known to have disabling impairment of moderate to greater severity. The aims of the study are to estimate the prevalence of NIHL in the police force; and study its association with age, sex, duration of service (years), smoking and alcohol habits, use of hearing protective devices, as well as preexisting chronic diseases. Methods: A cross-sectional study was conducted on 543 police personnel who had undergone periodic medical examination over a 12-month period. The diagnostic criteria for NIHL were (1) history of occupational noise exposure, (2) bilateral hearing loss, (3) hearing loss of ${\geq}25dBA$ at 4,000 Hz in two consecutive audiograms, and (4) no significant medical history affecting hearing. Severity of NIHL was based on the World Health Organization grading. Results: Males (74.8%) made up the majority of the police force. The mean age for police personnel was $35.55{\pm}9.57years$, and the mean duration of service was $14.75{\pm}9.39years$. Compliance with the usage of hearing protective devices was seen in 64.4%. The prevalence of NIHL in this study population was 34.2%, with a higher prevalence in males (37.7%) than in females (23.9%). The study also showed strong associations between NIHL and male sex (odds ratio, 1.9; P < 0.05), and hypertension (odds ratio, 3.3; P < 0.001). Overall, 93% were found to have mild NIHL, 3.5% had moderate NIHL, and 3.5% had severe NIHL. No police personnel were found to have profound hearing loss. Conclusion: The prevalence of NIHL in this study is high compared to other similar studies among police personnel. This study shows that increasing age, male, presence of hypertension, diabetes, and longer duration of service are significant associated factors for NIHL. Preventative strategies include health surveillance, implementation of a hearing conservation program, and legislation.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.587-597
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• 2004

Over the past 20 years, great strides have been made in research regarding the mechanisms involved in the progression of carious lesions, but new equipment and research tools need to be developed to continue these advancements in caries research. Various methods have been applied to reduce the incidence of carious lesions, which have led to a significant decrease in the number of occlusal caries, but a concurrent increase in the proportion of proximal carious lesions. New diagnostic equipment has been developed to detect early stage carious lesions, and these have demonstrated excellent laboratory results and show promise in clinical applications. The research presented here examines the efficacy of the newly developed $DIFOTI^{TM}$ system in detecting proximal carious lesions compared to traditional intraoral exam and bitewing radiography, possible problems or deficiencies of using the system in clinic, possible improvements that can be made to the system, and the efficacy of detecting early, reversible carious lesions that can be remineralized by preventative fluoride applications. The subject pool consisted of 23 grammer school age patients just prior to entering the mixed dentition phase. Each patient was given a thorough oral examination, radiographic examination consisting of bitewing radiographs of the posterior teeth, and $DIFOTI^{TM}$ examination of the anterior and posterior teeth. Each examination was carried out two times by two examiners, and the data were statistically analyzed. The results are as follows: 1. The mean alpha value of reliability test of the visual oral examination was as follows; occlusal surface was 0.8470. mesial surface was 0.6430, distal surface was 0.5727. lingual surface was 0.2807 and distal surface was 0.2339. When the examination was limited to posterior teeth, the mean alpha value was as follows; occlusal surface was 0.8577, distal surface was 0.8211, lingual surface was 0.7728, buccal surface was 0.7152 and mesial surface was 0.6782. 2. The alpha value of reliability test of the radiographic analysis of carious lesions of the occlusal, mesial, and distal surfaces was 0.8500. 3. The alpha value of reliability test of the $DIFOTI^{TM}$ diagnostic analysis of carious lesions of the occlusal, buccal, lingual, mesial, and distal surfaces was determined to be 0.7917. 4. The $DIFOTI^{TM}$ diagnostic system was found to be the most accurate means of detecting occlusal, buccal, and lingual surface carious lesions (p<0.05), while mesial and distal proximal carious lesions were most accurately assessed using bitewing radiography (p<0.05).