• Title/Summary/Keyword: Diction

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Prediction of Oil Lifetime due to Overheating of Oil and Bearing Housing in a Pump (펌프 베어링하우징에서 베어링과 오일의 과열 및 오일수명 예측)

  • 한상규;강병하;이봉주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.5
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    • pp.408-413
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    • 2004
  • An experimental study has been carried out to investigate overheating of oil and bearing housing during pump operation. This problem is of particular interest in the pre diction of lifetime and failure of pump. Transient variation of oil temperature as well as bearing housing temperature is measured to study the effect of oil viscosity, oil amount, and discharge flow rate of pump. It is found that optimal oil quantity as well as proper viscosity of oil is required to keep the safe temperature level of oil and bearing housing in a pump. The oil temperature at steady state is almost not affected by discharge flow rate in the range of discharge flow rates considered in the present study.

Model based Fault Detection and Diagnosis of Induction Motors using Probability Density Estimation (확률분포추정기법을 이용한 유도전동기의 모델기반 고장진단 알고리즘 개발)

  • Kim, Kwang-Su;Lee, Young-Jin;Song, Xian-Hui;Lee, Kwon-Soon
    • Proceedings of the KIEE Conference
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    • 2008.04b
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    • pp.171-173
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    • 2008
  • This paper presents stochastic methodology based fault diction and diagnosis algorithm for induction motor systems. First, we construct probability distribution model from healthy motors and then probability distribution for faulty motors is recursively calculated by means of the proposed probability estimation. We measure motor current with hall sensors as system state. The estimated probability is compared to the model to generate a residue signal which is utilized for fault detection and diagnosis, that is, where a fault is occurred. We carry out real-time induction motor experiment to evaluate efficiency and reliability of the proposed approach.

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Conditional Event Matching Prediction of Nonlinear Phenomena of Insulator Pollution in Coastal Substations Based on Actual Database

  • Nakamura, Masatoshi;Goto, Satoru;Katafuchi, Tatsuro;Taniguchi, Takashi
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.157-160
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    • 1999
  • A prediction method of conditional event matching pre-diction (EMP) for a purpose of predicting nonlinear phenomena of insulator pollution was proposed in this paper. The EMP was used if the conditional probability for increase of insulator pollution exceeded a threshold value. A performance of the EMP was strongly related to selection of database of events and a closeness function. By use of the prediction of the insulator pollution based on the conditional EMP, reliable decision making for the washing timing of the polluted insulators was e-valuated based on actual data in Kasatsu substation, Japan.

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Model based Fault Detection and Diagnosis of Induction Motors using Online Probability Density Estimation (온라인 확률추정기법을 이용한 모델기반 유도전동기의 고장진단 알고리즘 연구)

  • Kim, Kwang-Su;Lee, Young-Jin;Lee, Kwon-Soon
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1503-1504
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    • 2008
  • This paper presents stochastic methodology based fault diction and diagnosis algorithm for induction motor systems. First, we construct probability distribution model from healthy motors and then probability distribution for faulty motors is recursively calculated by means of the proposed probability estimation. We measure motor current with hall sensors as system state. The estimated probability is compared to the model to generate a residue signal which is utilized for fault detection and diagnosis, that is, where a fault is occurred. We carry out real-time induction motor experiment to evaluate efficiency and reliability of the proposed approach.

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Detection of Mycoplasma Infection in Cultured Cells on the Basis of Molecular Profiling of Host Responses

  • Chung, Tae Su;Kim, Ju Han;Lee, Young-Ju;Park, Woong-Yang
    • Genomics & Informatics
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    • v.3 no.3
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    • pp.63-67
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    • 2005
  • Adaptive responses to diverse microbial pathogens might be limited in relatively few types. Host cell responses to pathogens are believed to be patterned or stereotyped along with species or class. We tried to compose the host response to Mycoplasma in terms of cellular gene expression. Although gene expression profile of two host HeLa and 293 cells were quite different each other, 30 genes were differentially expressed by mycoplasma infection in both of HeLa and 293 cells. Six of them (PR48, MADH4, MKPX, CRK, RBM7, NEK3) were related to cell cycle or proliferation. Another category of genes like IL1 HY1, KLRF1, TNFSF14, GBP1 were host defense to elicit immune responses. With this set of genes, we establish the prediction model for mycoplasma contamination.

Study on Fatigue Behavior of Carbon Fiber Reinforced Polyimide Composites (탄소섬유강화 복합적층판의 피로특성에 관한 연구)

  • 이창수;황운봉;한경섭;윤병일
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.1
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    • pp.49-60
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    • 1991
  • Fatigue behavior of carbon fiber reinforced polyimide composite materials was studied experimentally and analytically. The physical variables, such as cyclic displacements and hysteresis loop energy were observed during fatigue tests. Fatigue life of the investigated [0/90]$_{2S}$ laminates was predicted by H'||'&'||'H models which was proposed based on the fatigue modulus and resultant strain. The predicted fatigue life by H'||'&'||'H curves was reasonably close to the experimental data. Fractography study shows that fatigue failure mechanism of [0/90]$_{2S}$ laminated composite materials involves failure break, matrix tearing and fiber-matrix debonding as well as delamination of layers.

Development of Novel Algorithm for Anti-Islanding of Grid-Connected PV Inverter (계통연계형 태양광 인버터의 단독운전 방지를 위한 새로운 알고리즘 개발)

  • Choi, Jung-Sik;Ko, Jae-Sub;Chung, Dong-Hwa
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.10
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    • pp.76-86
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    • 2011
  • This paper proposes novel algorithm for anti-islanding of grid-connected photovoltaic(PV) inverter. The islanding of PV systems can cause a variety of problems such as deterioration in power quality and electric shock. To prevent islanding, many anti-islanding methods are researched. Typical methods of anti-islanding are active frequency drift(AFD) and active frequency drift positive feedback(AFDPF). However, the AFD has problem that widely exists non diction zone(NDZ). The AFDPF is a method that improves the AFD method and is detected islanding by changing the chopping fraction(cf). However, The AFDPF does not detect when cf is very small and does not satisfy the IEEE Std. 929-2000 when cf is very big. Therefore, this paper proposes novel anti-islanding method that is simple to implement using virtual resister. The anti-islanding method proposed in this paper is compared with conventional method. The validity of this paper is proved using this result.

A Study on the Effects of the Hospitalization Stress on the Sleep Pattern (입원 스트레스가 수면형태에 미치는 영향(Johnson의 간호모형 적용))

  • 이소우
    • Journal of Korean Academy of Nursing
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    • v.16 no.2
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    • pp.36-43
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    • 1986
  • The main purpose of this study was to explore the effect of the stress of hospitalization on the sleep pattern. Additionaly, this study was also to demonstrate how Johnson's nursing model may be applied to as nursing process. 104 hospitalized patients on surgical and medical wards were asked to rate 49 stress producing events associated with experience of hospitalization and sleep pattern scale. Five university hospitals were used as the setting for this study. Data for the study were collected by patient interview during hospitalization, self-reports and review of charts. For the analysis of the data, the pearson's correlation analysis of covariance and regression analysis were used. The results of this study were stated as follows; 1. The mean of the hospital stress scores was 111.261(S.D.=26.160). This means that the level of the hospitalization stress is high. The mean of the sleep pattern scores was 12.204(S.D. =2.615) This means that the characteristic's of the sleep pattern is poor. 2. The relationship between the hospitalization stress and sleep pattern was statistically significant at .01 level. 3. The effect of the hospitalization stress influenced strongly on the sleep pattern after sex, trait anxiety as covariates controlled. 4. The hospitalization stress revealed a 12% pre-diction as an influenced factor for the sleep pattern. Therefore, It can he said that the hospital stress did contribute significantly to the characteristics of the sleep pattern. Johnson's model can he also said that it is useful for the the assessment and diagnosis in nursing process.

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20세기말 패션 디자인에 나타난 신표현주의적 이미지에 관한 연구

  • 이효진
    • Journal of the Korean Society of Costume
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    • v.40
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    • pp.5-23
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    • 1998
  • The main purpose of this study was intended to analyze the image of N대-Expressionism represented in the late of 20th century fashion design. By the late 1960s and the early 1970s. the prevailing notion of modernity, which had pushed the limits of art beyond previous boundaries, had begun to lose its urgency. Critics called the new pluralistic era which the West was entering Post-Modern. Furthermore, the predominance of America and the New York scene is diminishing, and artistic leadership is now international. Post-Modernism dialectcally made denial of Modernism as likely as New Image Painting and Decorative Pattern Painting Art in 1970's and it was availed as a dialectcal means for the pre-diction of new comings that would be appeared at painting art in 1980's. New Image Painting has been called as Neo-Expressionism. The N대-Expressionists selected human's feature because appeared flankly, directly irregular agitation in the visual effect and they believed human's destructive and amputate body was cruelty. So they express it on the surface canvas. Under the these background, the image of Neo-Expressionism was represented in the late of 20th century fashion design such as the upside-down image of human feature, the image as ameditation on German myth and history, culture, the ecletic image is made of use a mixture of material. The properties of composition, line, color, texture, and form, common to all plastic art, are now more readily recognized and historically valued in every work. That is, individuality, humanity, and the human condition have been at the core of most Western art and Fashion design. Especially Fashion design has been one of the principal instruments used to examine our nature and to promote the notion of growth, self-understanding, and change.

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Detection of Facial Region and features from Color Images based on Skin Color and Deformable Model (스킨 컬러와 변형 모델에 기반한 컬러영상으로부터의 얼굴 및 얼굴 특성영역 추출)

  • 민경필;전준철;박구락
    • Journal of Internet Computing and Services
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    • v.3 no.6
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    • pp.13-24
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    • 2002
  • This paper presents an automatic approach to detect face and facial feature from face images based on the color information and deformable model. Skin color information has been widely used for face and facial feature diction since it is effective for object recognition and has less computational burden, In this paper, we propose how to compensates varying light condition and utilize the transformed YCbCr color model to detect candidates region of face and facial feature from color images, Moreover, the detected face facial feature areas are subsequently assigned to a initial condition of active contour model to extract optimal boundaries of face and facial feature by resolving initial boundary problem when the active contour is used, The experimental results show the efficiency of the proposed method, The face and facial feature information will be used for face recognition and facial feature descriptor.

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