• Title/Summary/Keyword: Pattern of Errors

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An Experimental Study on the Flow Pattern in the Vicinity of Pressure Measuring Hole of the Viscoelasitc Fluids (점탄성유체의 압력측정용 벽공부근의 유동모양에 관한 실험적 연구)

  • 김춘식
    • Journal of Advanced Marine Engineering and Technology
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    • v.4 no.1
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    • pp.23-31
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    • 1980
  • The fluid static pressure has been generally measured by means of a small hole leading to a measuring instrument. In case of viscoelastic fluids, however, it has been shown experimentally that a systematic error exists in measuring the static pressure by means of the small hole becuase viscoelasitc fluids have many properties that can not be observed in Newtonian fluids. In this paper, in order to examine the mechanism of the errors in measuring the static pressure of viscoelasitc fluids, flow patterns in the vicinity of static pressure measuring hole were photographically taken and observed graphically. The experiments to take photographs of flow patterns were performed by a parallel plate channel with the steady two-dimensional shear flow of viscoelastic fluids. Results of the experiment are classified as following three regions; (1) Arched symmetrical flow pattern region. (2) Asymmetrical flow pattern region. (3) Rectilinear symmetricl flow pattern region.

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Development of Web-based Diagnosis Expert System of Traditional Oriental Medicine (인터넷 기반 한의진단전문가 시스템(KHU-PIPE) 개발)

  • Choi Seung Hoon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.3
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    • pp.528-531
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    • 2002
  • In Traditional Oriental Medicine, there has been a growing needs for computerized diagnosis expert system, which can implement pre-diagnosis and correct the errors of practitioners. Therefore, we developed the expert system (KHU-PIPE : Kyung Hee University - Pattern Identification and Prescription Expert) for diagnosis and treatment. It has three characteristics as following. First. this system has the knowledge base which modified the standardized data designed by Chinese government during 1980s. Second, it provides the objective and standardized diagnosis as the results of pattern identification and their appropriate prescriptions for treatment. Third, it is applied to both LAN system and internet. Furthermore, it can be used as an educational methods for the practices of pattern identification and prescription, and provide the objective criteria for clinical studies and promote the Traditional Oriental Medicine as an evidence-based medicine.

Short-term Load Forecasting using Neural Network (신경회로망을 이용한 단기부하예측)

  • Koh, Hee-Soek;Lee, Chung-Sik;Kim, Hyun-Deuk;Lee, Hee-Chul
    • Proceedings of the KIEE Conference
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    • 1993.11a
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    • pp.29-31
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    • 1993
  • This paper presents Neural Network(NN) approach to short-term load forecasting. Input to the NN are past loads and the output is the predicted load for a given day. The NN is used to learn the relationship among past, current and future temperature and loads. Three different cases are presented. Case 1 divides into weekday and weekendday load pattern. Case 2 forcasts 24-hour ahead load. Case 3 searchs for the same load pattern as present load pattern in past load pattern. From result of forecasting, an average absolute percentage errors of case 1 shows 2.0%. That of case 2 shows 2.2, and That of case 3 shows 1.6%.

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The Influence of Chinese Falling-Rising Tone on the Pitch of Sino-Korean Words Pronounced by Chinese Learners: Focusing on the Partly-Different-Form-Same-Meaning Words (중국어 상성이 중국인의 한자어 발음에 미치는 영향 연구: 부분이형동의어를 중심으로)

  • Liu, Si Yang;Kim, Young-Joo
    • Phonetics and Speech Sciences
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    • v.4 no.2
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    • pp.21-31
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    • 2012
  • The purpose of this study is to find the influence of Chinese falling-rising tone on the pitch pattern of corresponding partly-different-form-same-meaning Sino-Korean words delivered by Chinese learners of Korean and to examine how the falling-rising tone of corresponding Chinese words affects the pitch patterns of Sino-Korean words. The scope of this research is limited to Chinese learners of Korean, especially on two groups of Sino-Korean words - AB:CB type and AB:AC type that the are second-most frequently occuring different-form-same-meaning Sino-Korean words. In this study, Chinese learners pronounced both Chinese words and corresponding Sino-Korean words. Learners' pitch patterns were recorded and analyzed using software and compared with the tone of corresponding Chinese words. Experimental results showed that AB:CB type Sino-Korean words were not affected by Chinese 'falling-rising tone - high and level tone'. As well as AB:CB type, experimental results showed there were no significant influence on the pitch pattern of AB:AC type Sino-Korean words by Chinese falling-rising tone. But it was clear that Chinese learners' made pitch errors on both AB:CB type and AB:AC type Sino-Korean words. In conclusion, the Chinese learners' pitch patterns of partly-different-form-same-meaning Sino-Korean words are different from Korean native speakers', but their pitch errors cannot be attributed to Chinese falling-rising tone.

Inference on the Joint Center of Rotation by Covariance Pattern Models

  • Kim, Jinuk
    • Korean Journal of Applied Biomechanics
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    • v.28 no.2
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    • pp.127-134
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    • 2018
  • Objective: In a statistical linear model estimating the center of rotation of a human hip joint, which is the parameter related to the mean of response vectors, assumptions of homoscedasticity and independence of position vectors measured repeatedly over time in the model result in an inefficient parameter. We, therefore, should take into account the variance-covariance structure of longitudinal responses. The purpose of this study was to estimate the efficient center of rotation vector of the hip joint by using covariance pattern models. Method: The covariance pattern models are used to model various kinds of covariance matrices of error vectors to take into account longitudinal data. The data acquired from functional motions to estimate hip joint center were applied to the models. Results: The results showed that the data were better fitted using various covariance pattern models than the general linear model assuming homoscedasticity and independence. Conclusion: The estimated joint centers of the covariance pattern models showed slight differences from those of the general linear model. The estimated standard errors of the joint center for covariance pattern models showed a large difference with those of the general linear model.

A Study on Roughness Measurement of Polished Surfaces Using Reflected Laser Beam Image (레이저빔 반사 화상을 이용한 연마면 거칠기 측정법에 관한 연구)

  • Shen, Yun-Feng;Lim, Han-Seok;Kim, Hwa-Young;Ahn , Jung-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.2 s.95
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    • pp.145-152
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    • 1999
  • This paper presents the principle and experimental results of a non-contact surface roughness measurement by means of screen projected pattern of lase beam reflected from a polished surface. In the reflected laser beam pattern especially from a fine surface like ground or polished one, light intensity varies from the center fo the image to its boundary as the Gaussian distribution. The standard deviation of a light intensity distribution is assumed to be a good non-contact estimator for measuring the surface roughnes, because the light reflectivity is known to be well related with the surface roughness. This method doesn't need to discriminate between the specularly reflected light and the diffusely reflected one, whereas the scattered laser intensity method must do. Nor it needs to adjust the change of light intensity caused by environmental lights or specimen materials. Reflected laser beam pattern narrowly spreads out in the vertical direction to tiny scratches on the polished surface due to abrasives. The deeper the scratch the more the dispersion, which means the rougher surface. The standard deviation of the pattern is nearly in proportion to the surface roughness. Measurement errors by this method are shown to be below 10 percent compared with those obtained by a common contact method. The inclination of measuring unit from the normal axis causes the measurement errors up to 10 percent for an angle of 4 degree. Therefore the proposed method can be used as an on-the-machine quick roughness estimator within 10 percent measurement error.

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Measuring Methods for Two-dimensional Position Referring to the Target Pattern (참조패턴 기반의 2차원 변위 측정 방법론)

  • Jung, Kwang Suk;Lee, Sang Heon;Park, Sung-Jun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.1
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    • pp.77-84
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    • 2013
  • In this paper, we review two-dimensional measuring methods referring to target patterns. The patterns consist of two linearly-repeated patterns or is designed repeatedly in two-dimension. The repeated properties are reflectivity, refractivity, air-gapping distance, capacitance, magnetic reluctance, electrical resistance and sloping gradient, etc. However, the optical methods are generally used for high speed processing and density, and their encoding principles are treated here. In case of two-dimensional pattern, as there is not inherently error between single units encoding the pattern except for the metrology frame errors, the end-effector position of an object accompanying the pattern can be measured with respect of the global frame without via error. Therefore, it is regarded as a substitute for laser interferometer with severe environmental constraints and has been applied to the high-accurate planar actuator.

A Joint Statistical Model for Word Spacing and Spelling Error Correction Simultaneously (띄어쓰기 및 철자 오류 동시교정을 위한 통계적 모델)

  • Noh, Hyung-Jong;Cha, Jeong-Won;Lee, GaryGeun-Bae
    • Journal of KIISE:Software and Applications
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    • v.34 no.2
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    • pp.131-139
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    • 2007
  • In this paper, we present a preprocessor which corrects word spacing errors and spelling correction errors simultaneously. The proposed expands noisy-channel model so that it corrects both errors in colloquial style sentences effectively, while preprocessing algorithms have limitations because they correct each error separately. Using Eojeol transition pattern dictionary and statistical data such as n-gram and Jaso transition probabilities, it minimizes the usage of dictionaries and produces the corrected candidates effectively. In experiments we did not get satisfactory results at current stage, we noticed that the proposed methodology has the utility by analyzing the errors. So we expect that the preprocessor will function as an effective error corrector for general colloquial style sentence by doing more improvements.

A Study on the Pattern Development for Forest Fire Safety Clothing (산불진화용 안전복 패턴 개발을 위한 연구)

  • Choi, Mee-Sung
    • Fashion & Textile Research Journal
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    • v.13 no.4
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    • pp.624-634
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    • 2011
  • The purpose of this study is to develop the pattern of safety clothes used at flat or mountainous areas and to identify the pattern of safety clothes by conducting experimental evaluation of virtual wear. Three subjects were selected, based on fire fighters' physical constitution. A prototype design for safety clothing was determined after in-depth interviewing of professionals and surveying of Forest service staff and related agency. Wearing test should be carried out in the order of pattern making, virtual and real wearing evaluation. For data analysis, technical statistical values should be obtained by using body measurements of subject, frequency analysis and T-test. The jacket is designed to have a front extension and the entire length of clothing enough for wearer to put on it over ordinary shirts or sweater. The collar of jacket is of round type. Cyber reality enables to identify the movement and activity of virtual fitting model and to find out errors or problems in safety clothing prior to on-the-spot wear test, thus raising the precision level of pattern. There was significant difference between real and virtual fit preference. The results show that the virtual try-on system need the development of a specific style.

Effects on Performance of Deployable Solid Antenna for Panel Misalignment (패널오차에 의한 전개형 솔리드 안테나 성능 영향)

  • Lee, Ji-Yong;Lee, Kyo-Il;Yoon, Seong-Sik;Lee, Taek-Kyung;Lee, Jae-Wook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.8
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    • pp.603-609
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    • 2017
  • In the deployable solid surface antennas, the effects on the performances of antenna due to the structural errors that occur during the deployment are analyzed. The deployable solid surface antennas employed in a satellite are launched in folded configuration and those are deployed in the space environment, and the effects on the antenna performance are calculated depending on the type of surface errors. When the deviation error occurs in one panel, the degradation of performance appears in the side where the incomplete deployment of panel occurs. By assuming that the panel error distribution is in cosine function, the effect of errors are calculated and analyzed with regard to the types and the magnitude of the error. If the antena panel error is uniform, the gain is reduced and pattern is symmetric. For the panel error of cosine 1 or 3 cycle, the main lobe tilts while the pattern is symmetric and the gain reduces for 2 or 4 cycle error.