LabVIEW를 이용한 소형 유도전동기의 권선고장 자동진단

宋明現(Myung-Hyun Song),朴奎南(Kyu-Nam Park),韓東奇(Dong-Gi Han),禹奕在(Hyeok-Jae Woo) 대한전기학회 2006 전기학회논문지 P Vol.55 No.4

In this paper, an auto detection method of stator winding fault of small induction motor is suggested. The Park's vector pattern which is obtained from 3-phase current signal by d-q transforming, is very good to detect winding fault. Comparing the Park's vector pattern of testing motor with its of healthy motor, the Park's vector pattern of fault motor is became an ellipse and the asymmetry is increased by the winding fault serios. So for detecting the dis-symmetry, id-filtered function, Min-value, and Max-value are suggested for auto detecting. Using LabVIEW programing, 3-phase healthy motor and several kind of winding fault motors are tested and the test results are shown that the suggested method can gives us a possibility of an auto detecting winding fault.

Park's Vector 기법을 이용한 소형 3상 유도 전동기의 권선 고장 진단

한민관(Min-kwan Han),우혁재(Hyeok-jae Woo),송명현(Myung-hyun Song),박규남(Kyu-nam Park) 대한전기학회 2003 대한전기학회 학술대회 논문집 Vol.2003 No.7

Winding Fault Diagnosis of Induction Motor Using Neural Network

Song Myung-Hyun,Park Kyu-Nam,Woo Hyeok-Jae,Lee Tae-Hun,Han Min-Kwan The Korea Institute of Information and Commucation 2005 Journal of information and communication convergen Vol.3 No.2

This paper proposed a fault diagnosis technique of induction motors winding fault based on an artificial neural network (ANN). This method used Park's vector pattern as input data of ANN. The ANN are firstly learned using this pattern, and then classify between 'healthy' and 'winding fault' (with 2, 10, and 20 shorted turn) induction motor under 0, 50, and $100\%$ load condition. Also the possibility of classification of untrained turn-fault and load condition are tested. The proposed method has been experimentally tested on a 3-phase, 1 HP squirrel-cage induction motor. The obtained results provided a high level of accuracy especially in small turn fault, and showed that it is a reliable method for industrial application

유한요소법을 이용한 밸브 스프링 리테이너의 형상설계

신혁수, 김동범, 박진근, 이인환, 조해용 충북대학교 산업과학기술연구소 2013 산업과학기술연구 논문집 Vol.27 No.2

A valve spring retainer is a small disc and located at intake and exhaust valve stem of engine. The retainer supports a valve spring and transmits spring force to a valve. Force is applied to the retainer repeatedly by a rocker arm. Durability of the retainer is an important factor of performance. Weight of retainer affect dynamic performance of engine. Therefore, optimal strength and weight of the retainer design are needed. In this study, stress distribution and fracture load of retainer were analyzed by using FEM to design optimal strength and weight. Static load test was simulated by using commercial FEM code DEFORM-3D. Shapes of the retainer to reduce weight were designed and analyzed to verify validity of it. Simulated results and experimental ones were compared

충수 절제술후 합병증을 감소시키기 위한 연구

박혁수,심명석,강진국 대한대장항문학회 1997 Annals of Coloproctolgy Vol.13 No.3

요추추간판 수핵탈출증에 대한 편측견인의 치료효과

박지환,권혁수 대한정형물리치료학회 1995 대한정형도수물리치료학회지 Vol.1 No.1

Markolf and Morris suggests that the deranged disk and torn annulus have an exellent re-covery ability from the position of spine extension, where the posterior annulus is not under stress and the gel can move anterioly. McKenzie explains side gliding as a combination of rotaion and side bending, his clinical studies indicate that side-gliding can gel laterally. In conclusion, the prone unilateral traction on the opposite side from the patient's pain along with the other treatment appered to have helped reduce those patient's pain. The method of treatment described in this report is suggest-ed for Korean physical therapists who treat patients suspected of posterolateral herniated nu-cleus pulposus.

전립선암과 전립선비대증 환자에서 혈청 유리 및 총전립선특이항원 측정의 의의

서혁준,박형민,권태균,정성광,김법완,이재태 경북대학교 의학연구소 2000 경북대학교병원의학연구소논문집 Vol.4 No.1

Purpose: This study was peformed to investigate whether the free to total PSA ratio(F/T PSA ratio) offers a better discriminant for the detection of patient with prostatic cancer(CaP) and those with benign prostatic hyperplasia(BPH) than serum total PSA alone. Materials and Methods: From September 1996 to February 1999, free and total PSA levels were measured on frozen sera samples of 154 men with BPH and 46 with CaP using immunoradiometric assay. Results: In all subjects, the mean total PSA was significantly higher in CaP group(72.57±66.58ng/ml) than BPH group(3.12±4.10ng/ml). The mean PSAD was significantly higher in CaP group(1.64± 1.86) than BPH group(0.08±0.01). The mean F/T PSA ratio was significantly lower in CaP group(0.19± 0.07) than BPH group(0.30±0.13). Among 41 subjects whose total PSA were between 4-20ng/ml, the mean PSAD was significantly higher in CaP group(0.37±7.16) than BPH group(0.17± 0.07), but the mean F/T PSA ratio was not significantly different between CaP(0.19± 0.10) and BPH group(0.25±7.13). By comparing the sensitivity and specificity of total PSA alone, PSAD and F/T PSA ratio on receiver operating characterislic (ROC) Cutie in all subiects and subiects with total PSA between 4-20ng/ml, F/T PSA ratio had no superiority than total PSA alone and PSAD for discrimination between CaP and BPH. Conclusions: We suggest that the F/T PSA ratio is not superior to total PSA alone and FSAD in the detection of prostatic cancer, and further evaluation of the usefulness of F/T PSA ratio should be required.

불안정판 위에서 후방 유선형 신발이 척추기립근 및 하지 근 활성도에 미치는 영향

권혁규,권유정,박진현,Dennis W. Fell 대구대학교 특수교육재활과학연구소 2011 再活科學硏究 Vol.29 No.1

본 연구는 일반 신발과 후방 유선형 신발을 착용한 후 불안정판 위에서 척추세움근, 안쪽넓은근, 앞정강근, 장딴지근, 넙다리두갈래근의 근 활성도를 비교 하기 위한 것으로 성인 남녀 28명이 참가하였으며 대상자들은 일반 신발과 후방 유선형 신발을 신고 8단계의 BSS 기기 위에 15초 동안 서서 근활성도를 측정하였다. 이 연구의 결과를 종합해보면 후방 유선형 신발을 착용한 경우 일반 신발을 착용한 경우에 비해서 앞정강근과 안쪽 넓은근에서 상대적으로 더 높은 활성도를 보여주었다. 이러한 결과는 건강한 성인에서 후방 유선형 신발을 신었을 때 불안정한 면 위에서 균형을 유지하기 위해 발목의 자세 조절전략만으로도 균형을 유지하기에 충분한 것으로 생각되어진다. The purpose of this study was to compare muscle activation of erector spine and lower extremity such as tibialis anterior, gastrocnemius, medial hamstring and vastus medialis after wearing a pair of normal shoes and unstable shoes on the rocking surface. 28 university students who did not have any lower musculoskeletal and neurological disorders in the past were participated in this study. Each subject was standing for 15 seconds on the biodex stability system(BSS) of level 8 while wearing normal shoes and unstable shoes. we used Electromyography to measure muscle activation of elector spine and lower extremity and expressed muscle activation as a percentage of maximal voluntary isometric contraction (%MVIC). Paired t-test was used to compare the muscle activation of erector spine and lower extremity between normal shoes and unstable shoes. The result of this study was as follows. Tibialis anterior and vastus medialis showed relatively higher average electromyogram rates more than normal shoes(p<.05).

투입정보의 제시조건에 따른 정신지체아의 외현기억과 암묵기억

권혁용,박찬웅 대구대학교 사범대학 부설 교육연구소 2007 敎育硏究 Vol.3 No.1

The objectives of the present study were to examine the effects of input information presentation condition in the encoding stage on explicit memory and implicit memory in mentally retarded children and ordinary children and to test memory dissociation between explicit memory and implicit memory according to input information presentation condition. Based on the results of this study, we suggested effective input information presentation condition for mentally retarded children?fs learning and proposed the educational use of implicit memory, which is a relatively strong point of mentally retarded children. The subjects of this study were 30 mentally retarded children attending a special school or a special class at elementary school in Busan, and 30 ordinary kindergarteners and 1st?]grade elementary students. Thus, a total of 60 children participated in this research. This study was carried out through tests according to sense pattern and tests according to processing level. Tests according to sense pattern were a free recall test and a word completion test, which were conducted after a while from presenting input information in the conditions of words/ pictures, words/voices, and words/pictures/voices. Tests according to processing level were a free recall test and a word completion test, which were conducted after a while from presenting input information in the conditions of cognitive processing and semantic processing. Using SPSS 12.0, collected data were analyzed through repeated measures ANOVA to test the effect of interaction between the groups and the presentation conditions, and through simple main effect to analyze variables. In addition, the results of memory test according to presentation condition were analyzed through t-test in order to test memory dissociation. The results of this study are as follows. First, it was effective to present input information to the visual simple sense in mentally retarded children, and to the visual?]auditory complex sense in ordinary children. Second, it was effective to present input information after semantic processing in both mentally retarded children and ordinary children. In conclusion, the results of our study suggest that, for mentally retarded children, it is effective to present input information after semantic processing and targeting the visual simple sense, and the presentation condition has a relative strength in implicit memory, which is unintentional elicitation. 본 연구에서는 부호화 단계에서 투입정보의 제시조건(감각양상에 따른 제시조건과 처리수준에 따른 제시조건)이 정신지체아와 일반아동의 외현기억과 암묵기억에 어떠한 영향을 미치는가와 투입정보의 제시조건에 따른 외현기억과 암묵기억간의 기억해리현상을 검증하여, 정신지체아의 기억에 대한 특성과 정신지체아의 학습에 있어서 투입정보의 효과적인 제시조건을 밝히고 정신지체아의 상대적 강점인 암묵기억의 교육적 활용을 제기하는데 그목적이 있다.

요통환자에 있어서 요부굴곡운동과 요부신전 운동의 치료효과 비교연구

권혁수,박지환 대한정형물리치료학회 1996 대한정형도수물리치료학회지 Vol.2 No.1

To compare the treatment effects of back execise on functional status, spinal mobility, SLR, pain severity, and treatment results satisfaction, and to determine whether spinal exercises during the low back pain reduces recurrent episodes of back pain. 1. Flexion and extension exercise groups did not differ in any outcome over 4weeks. After 1 week, both exercise groups had reduced disability score, a higher proportion returning to work, and fewer subjects with a positive SLR compared with the control group. 2. There was no difference among regarding recurrence of low back pain after 6~12 months. 3. There was no difference for any outcomes between the flexion or extension groups. However, either exercise was slightly more effective than no exercise when patients with low back pain were treated.