• 제목/요약/키워드: Two-point correlation

검색결과 515건 처리시간 0.03초

A Robust Fingerprint Matching System Using Orientation Features

  • Kumar, Ravinder;Chandra, Pravin;Hanmandlu, Madasu
    • Journal of Information Processing Systems
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    • 제12권1호
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    • pp.83-99
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    • 2016
  • The latest research on the image-based fingerprint matching approaches indicates that they are less complex than the minutiae-based approaches when it comes to dealing with low quality images. Most of the approaches in the literature are not robust to fingerprint rotation and translation. In this paper, we develop a robust fingerprint matching system by extracting the circular region of interest (ROI) of a radius of 50 pixels centered at the core point. Maximizing their orientation correlation aligns two fingerprints that are to be matched. The modified Euclidean distance computed between the extracted orientation features of the sample and query images is used for matching. Extensive experiments were conducted over four benchmark fingerprint datasets of FVC2002 and two other proprietary databases of RFVC 2002 and the AITDB. The experimental results show the superiority of our proposed method over the well-known image-based approaches in the literature.

두 개의 가변 변수가 있는 냉매 증기압 상관식의 성능 평가 (Performance Assessment of Refrigerant Vapor-Pressure Equations with Two Adjustable Parameters)

  • 박경근
    • 설비공학논문집
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    • 제24권2호
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    • pp.129-135
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    • 2012
  • Performance of various temperature-dependent vapor-pressure equations with two adjustable parameters is assessed. These are Antoine, Miller, Zia-Thodos, Mejbri-Bellagi and other 10 equations. The equations are fitted to correlate the data from NIST Chemistry WebBook for 43 pure substance refrigerants from the critical point to the triple point. It was found that the Mejbri-Bellagi equation yields the lowest average absolute deviation of 0.37% compared with that of 0.58% of the Miller equation which is known to give better fit to experimental data than the Antoine equation(1.42%) does.

확률 분포 함수의 지수 곡선 접합을 이용한 RVE 적합성 평가 (Evaluation of RVE Suitability Based on Exponential Curve Fitting of a Probability Distribution Function)

  • 정상엽;윤태섭;한동석
    • 대한토목학회논문집
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    • 제30권5A호
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    • pp.425-431
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    • 2010
  • 2가지 이상의 재료로 구성된 다상(multi-phase) 재료는 상 분포에 따라 재료 특성이 다르기 때문에, 상 분포를 묘사할 수 있는 적절한 방법이 필요하다. 본 연구에서는 확률 분포 함수 two-point correlation function과 lineal-path function을 사용하여 재료 내부의 상 분포 상태를 확률적으로 묘사하였다. 수치 계산 방법으로 계산되는 확률 분포 함수를 3개의 매개 변수를 사용한 곡선 접합(curve fitting)을 이용하여 수식으로 표현하고, 적용성을 살펴보기 위하여 2상 합금 미세구조 가상 시편과 지반 모델 시편을 사용하였다. 이를 통해, 확률 분포 함수는 곡선 접합을 이용하여 지수 형태의 수식으로 표현이 가능하며, 이는 시편의 RVE로서의 활용 가능성을 판단하는데 사용될 수 있음을 확인하였다.

원격탐사자료와 GIS를 활용한 도시 표면온도의 공간적 분포특성에 관한 연구 (A Study on the Spatial Distribution Characteristic of Urban Surface Temperature using Remotely Sensed Data and GIS)

  • 조명희;이광재;김운수
    • 한국지리정보학회지
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    • 제4권1호
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    • pp.57-66
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    • 2001
  • 본 연구에서는 도시표면온도를 추출하기 위하여 다시기 Landsat TM band 6 영상을 이용하여 과학기술부의 4가지 모델 즉 two-point linear model, linear regression model, quadratic regression model, cubic regression model에 대하여 각각 공간분석을 실시하였으며 그 결과를 AWS(automatic weather station) 관측자료와 상관 및 회귀분석 함과 동시에 GIS 공간분석 기법을 이용하여 도시 표면온도의 공간적 분포특성을 규명하였다. Landsat TM band 6으로부터 추출된 표면온도를 기초로 하여 토지피복별 표면온도 분포를 분석한 결과 도시 및 나지 지역이 가장 높은 온도분포대를 형성하고 있었으며, 표면온도와 NDVI간의 상관분석결과 평균 -0.85 정도의 음의 상관성을 확인할 수 있었다. 이와 같은 결과는 향후 기상환경 특성을 고려한 도시계획수립에 있어 중요한 인자로 작용할 것으로 사료된다.

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An Anthropometric and Three-Dimensional Computed Tomographic Evaluation of Two-Point Fixation of Zygomatic Complex Fractures

  • Jo, Taehee;Kim, Junhyung
    • Archives of Plastic Surgery
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    • 제41권5호
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    • pp.493-499
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    • 2014
  • Background Maintaining stability and restoring the aesthetic appearance are the fundamental goals when managing zygomatic fractures. We aimed to evaluate the stability and anthropometric outcomes of zygomatic fracture patients who underwent two-point fixation involving the infraorbital rim and zygomaticomaxillary buttress via the transconjunctival and gingivobuccal approaches without any skin incisions. Methods We examined 15 zygomatic fracture patients who underwent two-point fixation during a 3-year period. Stability was evaluated using three-dimensional facial bone computed tomography. Superoinferior and anteroposterior displacement of the zygoma was quantified. The aesthetic appearance of the periorbital region was evaluated using indirect anthropometry with standardized clinical photographs. The ratios between the eye fissure height and width, and lower iris coverage ratio were used to evaluate aesthetical changes. The bony displacement and aesthetic ratios were analyzed using Wilcoxon or Friedman tests. The correlation between the preoperative zygoma position and anthropometric values was analyzed. Results The positions of the zygoma were similar to those on the contralateral side at the long-term follow-up. The preoperative anthropometric measurements on the fractured side differed from those on the contralateral side, although these values were close to the normal values at the long-term follow-up. Furthermore, we noted that the anteroposterior displacement strongly positively correlated with the lower iris coverage rate (Spearman's coefficient=0.678, P=0.005). Conclusions Two-point fixation of zygomatic fractures achieved stable outcomes on long-term follow-up, and also appeared to be reliable in restoring the aesthetic appearance of the periorbital region.

The Sintering Behaviour of Fe-Mn-C Powder System, Correlation between Thermodynamics and Sintering Process, Mn Distribution, Microstructure

  • Hryha, Eduard;Dudrova, Eva
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.839-840
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    • 2006
  • Sintering behavior of the Fe-0.8Mn-0.5C powder system was studied on the specimens with a density of ${\sim}7.0g/cc$ sintered at $1120^{\circ}C$ for 30 min in a gas mixture of $7%H_2/93%N_2$ with the inlet dew point of $-60^{\circ}C$. During the atmosphere monitoring ($CO/CO_2$-content and dew point) was showed, that carbothermical reduction occurs in two different temperature ranges; three peaks of dew point profile also can be distinguished during sintering cycle as well. Following sintering the Mn-content distribution and microstructures around the Mn-source were micro-analytical evaluated; the results showed that manganese travels through porous iron matrix up to ${\sim}60{\mu}m$.

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A Nonlinear Theory for the Brusselator Near the Critical Point Caused by Diffusion

  • Han, Keun-Ok;Lee, Dong-J.;Lee, Jong-Myung;Shin, Kook-Joe;Ko, Seuk-Beum
    • Bulletin of the Korean Chemical Society
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    • 제7권3호
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    • pp.224-228
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    • 1986
  • A nonlinear theory is presented for the fluctuations of intermediates in the Brusselator near the critical point caused by diffusion. The method used is the two time scaling method different from the conventional method in the sense that a slight nonlinear effect is included in the initial time region where the linear approximation is conventionally valid. The result obtained by the nonlinear theory shows that fluctuations close to the critical point approach the value of a stable steady state or deviate infinitely from an unstable steady state, as time goes to infinity, while the linear theory gives approximately time-independent fluctuations. A brief discussion is given for the correlation at a time between fluctuating intermediates when the system approaches a stable steady state.

순환벡터처리에 의한 디지털 영상복원에 관한 연구 (A Study on Improvement in Digital Image Restoration by a Recursive Vector Processing)

  • 이대영;이윤현
    • 한국통신학회논문지
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    • 제8권3호
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    • pp.105-112
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    • 1983
  • 本論文은 線形空間的不變인 段損(blur)과 自色가우스性雜音에 의해 損傷된 映像에 대한 循環復元(recursive restoration)技法을 論하였다. 映像은 確率設計學的으로 그 平均과 相關函數(correlation function)에 의해 特徵지워진다. 隣接모델(neighborhood model)에 指數的自己相關函數(exponential autocorrelation function)가 사용되며 解析이 간단하고 편리하므로 映像度相關函數를 나타내는데 벡터 모델이 사용된다. 이 벡터 모델을 基本으로 한 映像表現에 있어서 離散的, 統計學的인 12點隣接모델이 開發되고 次元의 增加를 抑制하며 破損되고 雜音섞인 映像을 復元하기 위한 窓(window)移動處理技法이 使用되었다. 12點隣接모델 8點隣接모델보다 優秀한 것으로 나타나며 隣接의 많은 畵素를 요하는 精密畵像에 適合함을 보인다. 이 結果는 線形필터링을 요하는 映像處理에 널리 이용될 수 있음을 나타낸다.

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농촌노인의 영적안녕과 희망, 지각된 건강상태에 관한 연구 (A Correlation study on Spiritual Wellbeing, Hope and Perceived Health Status of the Rural Elderly)

  • 김정남
    • 한국보건간호학회지
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    • 제18권2호
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    • pp.342-357
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    • 2004
  • A descriptive correlation study was done to provide a basic data for comprehensive nursing care by analyzing the relationship between spiritual wellbeing, hope and perceived health status of the rural elderly. 130 respondents who lived at their homes and nursing homes for elders in D county. Kyungbuk province were selected and their age was over 60 years old. Paloutzian and Ellison(1982)'s spiritual wellbeing scale. Nowotny(l989)'s hope scale and Northern Illinois University's health self rating scale was used. From September 2nd to September 30th, 2002, ready made questionnaires were handed out by researcher and two well trained nurse research assistants. to those who can fill it out and for those who cannot fill out the questionnaires alone, the researcher and assistants read it and finished by interview. This study used Pearson's correlation coefficient for the hypothetic test and the average point and standard deviation of spiritual wellbeing, hope, and perceived health status were checked. To find out the difference between spiritual wellbeing, hope, and perceived health status by general characteristics ANOVA and Tukey test were used. The results are as follows : 1. The mean score for spiritual wellbeing of the rural elders was $49.94(\pm5.62)$ in a possible range of 20-80. The mean score of religious wellbeing was $25.20(\pm3.91)$ and that of existential wellbeing was $24.74(\pm2.83)$ in a possible range of 10-40. The average point of religious wellbeing was $2.52(\pm0.39)$ points and existential wellbeing was $2.47(\pm0.28)$ points to 4 point full marks. 2. The mean score for hope was $67.68(\pm10.92)$ in a possible range of 29-116. The average point of hope was $2.33(\pm0.38)$ points to 4 point full marks. 3. The mean score for perceived health status was $9.95(\pm2.66)$ in a possible range of 4-14. The average point of perceived health status was $2.15(\pm0.72)$ point to 4 point full marks. 4. In testing the hypothesis concerning the relationship between spiritual wellbeing and hope, there was a statistically positive correlation(r=0.621. p=0.000). 5. In testing the hypothesis concerning the relationship between hope and perceived health status, there was a statistically positive correlation(r=0.305, p=0.000). 6. There were significant differences in spiritual wellbeing according to age(F=5.60, p=0.000), religion(F=11.61. p=0.000), family status(F=2.86, p=0.040) and average monthly pocket money(F=4.32, p=0.015). 7. There were significant differences in hope according to age(F=16.49, p=0.000), religion (F=3.56, p=0.009), educational level(F=8.94, p=0.000), present occupation(t=-3.13, p=0.002), family status(F=5.90, p=0.001) and average monthly pocket money(F=3.41. p=0.036). 8. There were significant differences in perceived health status according to present occupation(t=-2.16, p=0.033) average monthly pocket money(F=4.11, p=0.019). From the above results it can be concluded that: There was a positive correlation between spiritual wellbeing and hope, hope and perceived health status. There was no positive correlation between spiritual wellbeing and perceived health status. For futher study, adequate spiritual wellbeing scale and hope scale for rural elders should be developed and, age and religion factors has to be reconsidered. When the nurse implicate the nursing intervention which can be promote the spiritual wellbeing and hope, rural elder's spiritual wellbeing and hope can be improved and at the same time, their perceived health status also can be improved.

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A User-friendly Remote Speech Input Method in Spontaneous Speech Recognition System

  • Suh, Young-Joo;Park, Jun;Lee, Young-Jik
    • The Journal of the Acoustical Society of Korea
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    • 제17권2E호
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    • pp.38-46
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    • 1998
  • In this paper, we propose a remote speech input device, a new method of user-friendly speech input in spontaneous speech recognition system. We focus the user friendliness on hands-free and microphone independence in speech recognition applications. Our method adopts two algorithms, the automatic speech detection and the microphone array delay-and-sum beamforming (DSBF)-based speech enhancement. The automatic speech detection algorithm is composed of two stages; the detection of speech and nonspeech using the pitch information for the detected speech portion candidate. The DSBF algorithm adopts the time domain cross-correlation method as its time delay estimation. In the performance evaluation, the speech detection algorithm shows within-200 ms start point accuracy of 93%, 99% under 15dB, 20dB, and 25dB signal-to-noise ratio (SNR) environments, respectively and those for the end point are 72%, 89%, and 93% for the corresponding environments, respectively. The classification of speech and nonspeech for the start point detected region of input signal is performed by the pitch information-base method. The percentages of correct classification for speech and nonspeech input are 99% and 90%, respectively. The eight microphone array-based speech enhancement using the DSBF algorithm shows the maximum SNR gaing of 6dB over a single microphone and the error reductin of more than 15% in the spontaneous speech recognition domain.

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