• Applied Science and Convergence Technology
• /
• 제23권6호
• /
• pp.328-339
• /
• 2014

In this article, plasma monitoring tools and mulivariate analysis techniques were reviewed. Optical emission spectroscopy was reviewed for a chemical composition analysis tool and RF V-I probe for a physical analysis tool for plasma monitoring. Multivariate analysis techniques are discussed to the sensitivity improvement. Principal component analysis (PCA) is one of the widely adopted multivariate analysis techniques and its application to end-point detection of plasma etching process is discussed.

• Structural Monitoring and Maintenance
• /
• 제2권4호
• /
• pp.339-355
• /
• 2015

Corrosion of prestressed concrete structures is one of the main challenges that engineers face today. In response to this national need, this paper presents the results of a long-term project that aims at developing a structural health monitoring (SHM) technology for the nondestructive evaluation of prestressed structures. In this paper, the use of permanently installed low profile piezoelectric transducers (PZT) is proposed in order to record the acoustic emissions (AE) along the length of the strand. The results of an accelerated corrosion test are presented and k-means clustering is applied via principal component analysis (PCA) of AE features to provide an accurate diagnosis of the strand health. The proposed approach shows good correlation between acoustic emissions features and strand failure. Moreover, a clustering technique for the identification of false alarms is proposed.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
• /
• pp.219-222
• /
• 2001

The human speech sounds are use to diagnosis in oriental medicine with ‘0-sung’theory. In general, human voice are sound waves which generated by phonation. Two major parts of phonation are vocal cords and vocal tract. The uniqueness of individual vocal sound depend on structure and usage of their vocal cords and tract. In the oriental medicine, “0-sung (5-tones)” has been used to classify constitution of human body In order to characterize the “0-sung”, their frequency characteristics are investigated, and a principal frequency component is extracted. Then, the principal component is applied to classify sounds into “0-sung.”

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2005년도 추계학술대회논문집
• /
• pp.127-130
• /
• 2005

There are many methods in feature extraction have been developed. Recently, principal components analysis (PCA) and independent components analysis (ICA) is introduced for doing feature extraction. PCA and ICA linearly transform the original input into new uncorrelated and independent features space respectively In this paper, the feasibility of using nonlinear feature extraction will be studied. This method will employ the PCA and ICA procedure and adopt the kernel trick to nonlinearly map the data into a feature space. The goal of this study is to seek effectively useful feature for faults classification.

• Nuclear Engineering and Technology
• /
• 제52권9호
• /
• pp.2009-2016
• /
• 2020

A nuclear power plant is a large complex system with tens of thousands of components. To ensure plant safety, the early and accurate diagnosis of abnormal situations is an important factor. To prevent misdiagnosis, operating procedures provide the anticipated symptoms of abnormal situations. While the more severe emergency situations total less than ten cases and can be diagnosed by dozens of key plant parameters, abnormal situations on the other hand include hundreds of cases and a multitude of parameters that should be considered for diagnosis. The tasks required of operators to select the appropriate operating procedure by monitoring large amounts of information within a limited amount of time can burden operators. This paper aims to develop a system that can, in a short time and with high accuracy, select the appropriate operating procedure and sub-procedure in an abnormal situation. Correspondingly, the proposed model has two levels of prediction to determine the procedure level and the detailed cause of an event. Simulations were conducted to evaluate the developed model, with results demonstrating high levels of performance. The model is expected to reduce the workload of operators in abnormal situations by providing the appropriate procedure to ultimately improve plant safety.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2009년도 제38회 동계학술대회 초록집
• /
• pp.473-473
• /
• 2010

Plasma is widely used in various commercial etchers and chemical vapor deposition. Unfortunately, real-time plasma process monitoring is still difficult. Some methods of plasma diagnosis is improved, however, it is possible for real-time plasma diagnosis to use non-intrusive probe only. In this research, the object is to investigate the suitability of using impedance analysis and optical emission spectroscopy (OES) for real-time plasma process monitoring. It is assumed that plasma system is a equivalent circuit. Therefore, V-I probe is used for measuring impedance, which can be a new non-intrusive probe for plasma diagnosis. From impedance data, we tried to analyse physical properties of plasma. And OES, the other method of plasma diagnosis, is a typical non-intrusive probe for analyzing chemical properties. The amount of the OES data is typically large, so this poses a difficulty in extracting relevant information. To solve this problem, principal component analysis (PCA) can be used. For fundamental information, Ar plasma and $O_2$ plasma are used in this experiment. This method can be applied to real-time endpoint and fault detections.

• 한국가스학회지
• /
• 제18권3호
• /
• pp.53-59
• /
• 2014

본 연구에서는 비정상상태 운전을 기본으로 하는 CNG 충전소를 대상으로 다변량 통계분석방법 중의 하나인 다차원의 대용량 데이터 처리에 적합한 주성분분석(PCA) 기법을 사용하여 실시간 이상감지 및 진단이 가능한 모니터링 시스템을 제안하였다. CNG 충전소로부터 매초 간격으로 수집되는 7개의 압력센서 데이터와 5개의 온도센서 데이터의 주요 경향을 나타내는 변수들의 조합으로 주성분이라 불리는 새로운 특성변수들을 산출하고, 분산의 분포를 통해 특성변수의 계산으로부터 모델을 구축하였다. 모니터링은 구축된 모델을 통해 운전 중의 실시간 데이터를 반영하여 진행된다. 시스템 검증 및 정확성을 개선하기 위해 모니터링 테스트를 수행한 결과, 정상상태의 모든 데이터를 정상으로 판단하였고, 이상 데이터의 성공적인 검출 시 관련 변수를 추적하여 비정상 원인을 찾아낼 수 있었다.

• 간호행정학회지
• /
• 제3권2호
• /
• pp.151-165
• /
• 1997

A cost analysis for hospitalized patients was performed based on the KDRG classification in order to determine an appropriate nursing fee under the PPS(Prospective Payment System). The data was collected from 20 nursing units of three tertiary hospitals and two secondary hospitals from August 26 to September 15, 1996. The study consisted of 148 inpatients diagnosed for lens procedures(KDRG 03900), tonsillectomy &/or adenoidectomy(KDRG 16100), Cesarean section(KDRG 37000), or vaginal delivery(KDRG 37300) without any complications. The direct or indirect nursing hours of each patients were measured. Then, direct or indirect nursing expenditures of four nursing units, operating room and delivery room were computed. Finally, the resources used including average total nursing hours, average length of stay and average nursing cost of each KDRG were estimated as follows; 1) The average total nursing hours were 640 minutes for lens procedures, 403 minutes for tonsillectomy &/or adenoidectomy, 934 minutes for appendectomy with complicated principal diagnosis, 1,094 minutes for Cesarean section and 631 minutes for vaginal delivery. Significant differences were found in average total nursing hours among hospitals. 2) The average length of stay in lens procedures were 5 days, 4 days for tonsillectomy &/or adenoidectomy, 6 days for appendectomy with complicated principal diagnosis, 8 days for Cesarean section and 3 days for vaginal delivery. All results were within normal determined by the Ministry of Health and Welfare although significant differences existed among hospitals, especially with average length of stay for leng procedures between tertiary hospitals and secondary hospitals which was greater than for those of others. 3) The average nursing cost were 87,146 Won for lens procedures, 69,600 Won for tonsillectomy &/or adenoidectomy, 128,337 Won for appendectomy with complicated principal diagnosis, 151,769 Won for Cesarean section and 85,403 Won for vaginal delivery. These costs were 7.6%, 13.0%, 13.0%, 16.0% and 22.0%, respectively, of the official price fixed by the Ministry of Health and Welfare under the prospective payment system. Research for the analysis of nursing costs according to the severity of illness for those KDRGs shoud be carried out within the period of the PPS pilot project. In addition, a proper nursing fee schedule for a new reimbursement system based upon the result of the above research should be prepared in the near future.

• 한국산학기술학회논문지
• /
• 제11권12호
• /
• pp.4863-4872
• /
• 2010

본 연구는 농 어촌지역 환자들을 대상으로 질병양상을 살펴보고 의료이용 실태를 분석하여 농 어촌지역 의료 관련 기관의 보건의료서비스 계획수립에 필요한 자료를 제공 하고자 시행되었다. 노령화가 진행된 농 어촌지역 G도 G군에 소재한 종합병원을 대상으로 2009년 7월부터 12월까지 6개월 동안 퇴원환자 2,365건 전수의 의무기록 자료를 토대로 분석하였다. 분석결과, 조사대상 환자의 성별은 남자 55.3%, 여자 44.7%, 연령별은 70세 이상 후기 고령자가 42%로 나타냈다. 입원유형별로는 외래경유 입원환자가 65.5%이며, 진료과목으로는 내과 49.7%, 정형외과 16.7%, 신경외과 13.8% 순이었다. 주 진단명(3단 분류)별 10대 다 빈도에서 S00-T98 18.4%, J00-J99 15.5%, I00-I99 11.5% 순이었다. 평균재원일수는 14.8일이었으며, 주 진단명을 포함한 상병개수는 평균 5.6개이었다. 주 진단명(3단 분류) 다빈도 10대에서 성별, 보험유형별, 입원경로, 연령별 분포 등이 통계적으로 유의한 차이가 있었다. 월별 주 진단명(3단 분류) 다 빈도 10대 분류 분포는 통계적 유의한 차이가 있었다. 주 진단명(3단 분류) 다 빈도 10대분류에 따른 평균재원일수와 상병개수는 통계적으로 유의한 차이가 있었다. 결론적으로, 농 어촌지역의 질병분포는 작업환경과 연중 신체적 무리가 가는 노동행위에 따른 외상성 질환 및 호흡기 질환과 노령화에 따른 각종 만성질환 등 이었다.

• 대한치과의사협회지
• /
• 제48권5호
• /
• pp.355-364
• /
• 2010

The frequency of mucosal and cutaneous fungal infection is increasing worldwide, which is due to the increase of immunocompromised patients. Candida albicans are the principal species associated with human oral mycosis and are known to be the most virulent among pathogenic Candida spp. In this review, oral candidiasis were classified and oral mucosal manifestations of candidiasis were filed. And its diagnosis and management would be reviewed briefly.