• 대한전기학회논문지:전력기술부문A
• /
• 제48권10호
• /
• pp.1272-1278
• /
• 1999

A fault is considered as a variation of physical parameters; therefore the design of fault detection and identification(FDI) can be reduced to the parameter identification of a non linear system and to the association of the set of the estimated parameters with the mode of faults. Neuro-Fuzzy Inference System which contains multiple linear models as consequent part is used to model nonlinear systems. Generally, the linear parameters in neuro-fuzzy inference system can be effectively utilized to fault diagnosis. In this paper, we proposes an FDI system for nonlinear systems using neuro-fuzzy inference system. The proposed diagnostic system consists of two neuro-fuzzy inference systems which operate in two different modes (parallel and series-parallel mode). It generates the parameter residuals associated with each modes of faults which can be further processed by additional RBF (Radial Basis Function) network to identify the faults. The proposed FDI scheme has been tested by simulation on two-tank system.

• Journal of Electrical Engineering and Technology
• /
• 제9권4호
• /
• pp.1418-1425
• /
• 2014

In ultrasonic medical imaging, spatial compounding of images is a technique where ultrasonic beam is steered to examine patient tissues in multiple angles. In the conventional ultrasonic diagnostic imaging, the steering of the ultrasonic beam is achieved electronically using the phased array transducer elements. In this paper, a spatial compounding approach is presented where the ultrasonic probe element is rotated mechanically and the beam steering is achieved mechanically. In the spatial compounding, target position is computed using the value of the rotation axis and the transducer array angular position. However, in the process of the rotation mechanism construction and the control system there arises the inevitable uncertainties in these values. These geometric parameter errors result in the target position error, and the consequence is a blurry compounded image. In order to reduce these target position errors, we present a spatial compounding scheme where error correcting transformation matrices are computed and applied to the raw images before spatial compounding to reduce the blurriness in the compounded image. The proposed scheme is illustrated using phantom and live scan images of human knee, and it is shown that the blurriness is effectively reduced.

• 임상간호연구
• /
• 제25권2호
• /
• pp.142-150
• /
• 2019

Purpose: The aim of this study was to evaluate the efficiency of the Humpty Dumpty Falls Scale as one of the falls risk assessment tools, and also to evaluate risk factors as predictors of falls in pediatric patient populations. Methods: In a retrospective, case-control design with data from the electronic medical records of 13 pediatric patients who fell and 1,941 who did not fall before matching and 429 who did not fall after matching by gender, age, diagnosis, and length of stay. Results: All the variables showed no significant differences after matching. At the cutoff score of 13, sensitivity, specificity, negative and positive predictive values were 92.3%, 37.1%, 99.9%, and 0.01%, respectively. The area under the Receiver Operating Characteristics was 0.597. The results from the logistic regression showed that the pediatric inpatient population who had higher risk scores was significantly associated with falls. The odds ratios ranged from 1.31 to 4.71 with 90% confidence interval. Conclusion: The saturation impairments criterion as one of the diagnostic parameter was negatively associated with falls, but the relative risk score was higher than the other criteria. Therefore, it seems that the diagnostic parameter seems to be required to verify results through large sample studies.

• 대한기계학회논문집A
• /
• 제37권6호
• /
• pp.797-804
• /
• 2013

본 논문에서는 환경 요인에 영향을 받아 평균이동이 발생하는 진동 파라메터에 대한 진단 방법을 연구하였다. 양산라인에서는 측정 시점에 따라 변화되는 환경요인에 대응되어 측정된 진동 파라메터의 평균이 변화될 수 있다. 이러한 경우 기존에 널리 사용되는 고정된 관리한계선을 사용하는 진단 기법을 사용할 경우 시간이 흐름에 따라 오분류가 발생한다. 이 한계점을 극복하기 위해 저자들은 회귀분석을 활용해 평균 변화의 주요 원인이 되는 환경요인간의 함수관계를 규명하고, 이를 평균이동의 예측에 활용해 각 진단 시점별로 경계 상한과 하한을 유연하게 변경하는 방법론을 제안한다. 제안된 방법론은 적용 과정에서 필요한 모수의 설정 시 레퍼런스 데이터 평가를 통해 합리적인 모수를 추정하는 것이 가능하고, 환경이 변화되는 각 시점에서 데이터에 대해 유연한 진단을 보장한다. H사의 디젤엔진 생산라인의 엔진 진동 검사 데이터를 활용하여 본 논문의 방법론에 대한 검증을 실시하였으며 만족스러운 결과를 도출하였다.

• Journal of Acupuncture Research
• /
• 제19권2호
• /
• pp.149-163
• /
• 2002

Objective : We have studied literatures of Renying Qi mouth comparison pulse diagnosis theory and distinguished the excess, deficiency and quick-temper of pulse as the measurement parameter of Renying Qi mouth pulse diagnosis. Methods : We have acquired pulse signals of Renying Qi mouth by using diagnostic equipment of Renying Qi mouth pulsation and estimated reappearance of pulse signals. Results : 1. The measurement parameter of Renying Qi mouth pulse diagnosis distinguishes the excess, deficiency and quick-temper of pulse through relative comparison of Renying Qi mouth. 2. When we acquired the pulse singals of Renying Qi mouth by using diagnostic equipment, the property, measuring area, bias pressure, contact or adhesion state of the sensor are considered. 3. As getting the pulse signal of Renying Qi mouth, the sensor of a sound detective mode is effective. 4. The diagnostic equipment of Renying Qi mouth pulse is assessed as being significant reappearance.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제6권4호
• /
• pp.211-216
• /
• 2017

본 논문에서는 조영증강 초음파 진단시스템에서 유용성과 성능을 개선하기 위한 영상처리 기법을 제안한다. 의료초음파 영상에서 진단 파라미터 데이터를 가시화 하는 방법론으로서 연속적인 픽셀 값을 갖는 전이시간 데이터의 표현과, 4가지 유형의 값으로 분류되는 병변 진단 파라미터 영상을 생성하는 방법을 제시한다. 또한 생성된 파라미터 영상에서 노이즈를 제거하기 위한 방법론으로서 MRF 모델을 이용한 영상개선 기법을 제안한다. 이러한 파라미터 영상 생성기법은 초음파 진단 데이터에서 조영증강 패턴의 동적인 변화에 대한 육안 판별의 한계를 극복할 수 있게 한다. 제안된 방법은 원영상에서 영역의 윤곽선을 명확하게 하며 4가지 색상을 통하여 병변의 특성에 관한 시각적 판단을 용이하게 한다. MRF기반 영상개선 과정에서 연속적인 픽셀 값에 대한 에너지함수를 정의하고 이를 최적화 하는 기법을 개발하였으며 실제 의료영상을 사용한 실험을 통하여 제안된 이론의 유용성을 평가하였다.

• 동의생리병리학회지
• /
• 제35권6호
• /
• pp.274-279
• /
• 2021

This study was conducted to find objective diagnostic indicators for the Eight Principle Pattern Identification using a pulse wave analyzer. Typology Complexion Pulse and Symptom data from 500 women over the age of 18 were used. Five experts made a diagnosis of Eight Principle Pattern Identification and divided the subjects into 'Yin-Yang', 'Exterior-Interior', 'Cold-Heat', 'Deficiency-Excess' groups. Their pulse waves were measured in the left and right radial arteries, and it was investigated whether there was a significant difference between groups in the pulse wave parameter values. 'Yin' group showed a significantly lower value in the left radial artery for Ener, Emin, EIX, T4T, T4TT parameters and in the Right for T2, T2T, T5. The Vmag, As and Ad parameters were significantly different between the 'Exterior' and 'Interior' groups. 'Heat' group showed a significantly higher value in the right radial artery for RAI/t parameter. 'Deficiency' group showed a significantly higher value in the right radial artery for W, Angl parameters. Through this study, significant pulse wave parameters were found, and they can be used as objective diagnostic indicators for Eight Principle Pattern Identification.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제51권5호
• /
• pp.213-221
• /
• 2002

In order to improve the reliability of XLPE cables, it is necessary to find the useful diagnostic parameter according to long term aging. This paper described the change of partial discharge(PD) phase Properties of XLPE cable insulation with branch type electrical tree degradation. for long term aging. To understand the PD Properties with $\phi$ -q-n distributed shape of XLPE insulation, specimens were prepared by 22.9㎸ distribution cable and made in a type of block(16${\times}$16${\times}$3[mm]). Ogura needles having tip radius of l0${\mu}{\textrm}{m}$ were inserted into each block pieces. The measuring system was consisted of PD detector, digitizer for digital conversion, VXI system for signal processing. The PD properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed. We analyzed the relationship between electrical properties(PD Quantity, PD initiation angle, PD extinction angle, PD occurrence angle : (PD extinction angle - PD initiation angle)) and the normalized aging rate. We found PD parameter, PD initiation angle and occurrence angle, which are a useful diagnostic parameter in estimating the branch type electrical tree for XLPE insulation condition.

• 전기학회논문지
• /
• 제64권12호
• /
• pp.1768-1775
• /
• 2015

Recent major domestic facilities, such as nuclear power plants, many control cables are installed and are degraded by long-term use, but research on deterioration diagnosis is lacking. In the event of a fault in the cable due to deterioration can be developed into a major accident such as the main plant is stopped, so the deterioration diagnostic techniques of high reliability for the cable is required. In this paper, proposes a methodology using a cable resonance that can effectively diagnose the deterioration of the cable. Prior to the test, we developed a setup for stable measuring the characteristics of the cable and it verified the suitable of the measurement set-up in terms of interactivity and reliability, also measured S-parameters applying verified measurement set-up to the cables that deterioration degree is different. Then, we had amplified the difference in resonance frequency between the healthy state and the deteriorated state using connection in a series of measured S-parameters. In a result from the method, we have verified that the more deteriorate the cables is, the more decrease the resonance frequency is. Measured results are justified by inducing the resonance frequency calculation of the cable from the S- parameters represented by the hyperbolic function formula. VNA(Vector Network Analyzer) for S-parameter measurements used in this study is Agilent E5061B and shielded twisted-pair cables was used for deterioration diagnostic test.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권6호
• /
• pp.2929-2932
• /
• 2014

Purpose: To evaluate the diagnostic performances of risk of malignancy index (RMI), CA-125 and ultrasound score in differentiating between benign and borderline or malignant ovarian tumors and find the best diagnostic test for referral of suspected malignant ovarian cases to gynaecologic oncologists. Materials and Methods: This prospective study covered 467 women with pelvic tumors scheduled for surgery at our hospital between July 2011 and July 2013. The RMI was obtained from ultrasound score, CA125 and menopausal status. The diagnostic values of each parameter and the RMI were determined and compared using Statistical Packages for Social Sciences Version 14.0.1. Results: In our study, 61% of ovarian tumors were malignant in the post-menopausal age group. RMI with a cut-off 150 had sensitivity of 84% and specificity of 97% in detecting ovarian cancer. CA-125>30 had a sensitivity of 84% and a specificity of 83%. An ultrasound score more than 2 had a sensitivity of 96% and specificity of 81%. RMI had the least false malignant cases thus avoiding unnecessary laparotomies. Ultrasound when used individually had the best sensitivity but poor specificity. Conclusions: Our study has demonstrated the RMI to be an easy, simple and applicable method in the primary evaluation of patients with pelvic masses. It can be used to refer suspected malignant patients to be operated by a gynaecologic oncologist. Other models of preoperative evaluation should be developed to improve the detection of early stage invasive, borderline and non-epithelial ovarian cancers.