• Title/Summary/Keyword: interest points

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Calculation of Tissue-Air Ratios(TAR) in Irregularly shaped Field for Co-60 Gamma Radiation (CO-60 감마선에 대한 부정형조사면의 조직공중선량비 (TAR) 계산)

  • Ji Young-Hoon
    • The Journal of Korean Society for Radiation Therapy
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    • v.3 no.1
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    • pp.27-36
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    • 1989
  • In order to calculate the dose on each interest point in five types of irregularly shaped fields used commonly in radiotherapy, the tissue-air ratios (TAR) in these fields for Go-60 gamma radiation were calculated using the newly devised SAR-chart. The TARs calculated from newly method of using the SAR-chart, computer method and approximation method at the interest point were compared to the TARs obtained from measurement. The result are as follows; In case of the interest points on central axis the calculated TARs in irregularly shaped fields by the above mentioned methods were well agreed within the error of $1\%$, whereas for the interest points on off-axis the calculated TARs were resulted in the maximum errors of $2.4\%,\;2.3\%$ and $8.8\%$ respectively. From these results, the accuracy of calculation method of using the SAR-chart was comfirmed.

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Front Points Tracking in the Region of Interest with Neural Network in Electrical Impedance Tomography

  • Seo, K.H.;Jeon, H.J.;Kim, J.H.;Choi, B.Y.;Kim, M.C.;Kim, S.;Kim, K.Y.
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.118-121
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    • 2003
  • In the conventional boundary estimation in EIT (Electrical Impedance Tomography), the interface between anomalies and background is expressed in usual as Fourier series and the boundary is reconstructed by obtaining the Fourier coefficients. This paper proposes a method for the boundary estimation, where the boundary of anomaly is approximated as the interpolation of front points located discretely along the boundary and is imaged by tracking the points in the region of interest. In the solution to the inverse problem to estimate the front points, the multi-layer neural network is introduced. For the verification of the proposed method, numerical experiments are conducted and the results indicate a good performance.

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Classification of Parents' Materialism Inclination Recognized by the Adolescents and Analysis of Their Financial Characteristics (청소년이 지각한 부모의 물질주의 성향과 그에 따른 유형 분류 및 재정적 특성 분석)

  • Hong, Eun-Sil
    • Journal of Families and Better Life
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    • v.26 no.5
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    • pp.377-390
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    • 2008
  • This paper investigated materialism inclination of the parents recognized by the adolescents and analysed the relationships between 5 categorized types about parents' materialism inclination and financial characteristics of the adolescents. Statistical analysis was achieved by using Cronbach'$\alpha$, paired t-test, one-way ANOVA, two-way ANOVA, Duncan's multiple range test, chi-square analysis, and Ward' hierarchical cluster analysis with a total of 801 questionnaires. The results are summarized as follows: First, the adolescents felt that calculated points of father and mother's materialism inclination were lower than median points and mother's inclination for materialism was higher than that of father. Second, five categories were classified according to materialism inclination of parents. First classified category was the type which showed both parents had little interest in materials and the second category was the type which father had strong interest in materials. The third one was the type which mother had strong interest in materials. The last two categories were the ones which both parents had much interest in materials. Final result of this study revealed that attitudes of the adolescents for materialism and money were higher for those whose parents had strong interest in materialism than those whose parents had little materialism interest. They showed not only the behaviors of impulsive and overspending consumption but also low financial satisfaction and high financial stress.

Gabor Descriptors Extraction in the SURF Feature Point for Improvement Accuracy in Face Recognition (얼굴 인식의 정확도 향상을 위한 SURF 특징점에서의 Gabor 기술어 추출)

  • Lee, Jae-Yong;Kim, Ji-Eun;Oh, Seoung-Jun
    • Journal of Broadcast Engineering
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    • v.17 no.5
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    • pp.808-816
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    • 2012
  • Face recognition has been actively studied and developed in various fields. In recent years, interest point extraction algorithms mainly used for object recognition were being applied to face recognition. The SURF(Speeded Up Robust Features) algorithm was used in this paper which was one of typical interest point extraction algorithms. Generally, the interest points extracted from human faces are less distinctive than the interest points extracted from objects due to the similar shapes of human faces. Thus, the accuracy of the face recognition using SURF tends to be low. In order to improve it, we propose a face recognition algorithm which performs interest point extraction by SURF and the Gabor wavelet transform to extract descriptors from the interest points. In the result, the proposed method shows around 23% better recognition accuracy than SURF-based conventional methods.

HIGH ACCURACY POINTS OF WAVELET APPROXIMATION

  • Kwon, Soon-Geol
    • Journal of applied mathematics & informatics
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    • v.27 no.1_2
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    • pp.69-78
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    • 2009
  • The accuracy of wavelet approximation at resolution h = $2^{-k}$ to a smooth function f is limited by O($h^M$), where M is the number of vanishing moments of the mother wavelet ${\psi}$; that is, the approximation order of wavelet approximation is M - 1. High accuracy points of wavelet approximation are of interest in some applications such as signal processing and numerical approximation. In this paper, we prove the scaling and translating properties of high accuracy points of wavelet approximation. To illustrate the results in this paper, we also present two examples of high accuracy points of wavelet approximation.

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Improving Matching Performance of SURF Using Color and Relative Position (위치와 색상 정보를 사용한 SURF 정합 성능 향상 기법)

  • Lee, KyungSeung;Kim, Daehoon;Rho, Seungmin;Hwang, Eenjun
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.394-400
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    • 2012
  • SURF is a robust local invariant feature descriptor and has been used in many applications such as object recognition. Even though this algorithm has similar matching accuracy compared to the SIFT, which is another popular feature extraction algorithm, it has advantage in matching time. However, these descriptors do not consider relative location information of extracted interesting points to guarantee rotation invariance. Also, since they use gray image of original color image, they do not use the color information of images, either. In this paper, we propose a method for improving matching performance of SURF descriptor using the color and relative location information of interest points. The location information is built from the angles between the line connecting the centers of interest points and the orientation line constructed for the center of each interest points. For the color information, color histogram is constructed for the region of each interest point. We show the performance of our scheme through experiments.

Face Recognition based on SURF Interest Point Extraction Algorithm (SURF 특징점 추출 알고리즘을 이용한 얼굴인식 연구)

  • Kang, Min-Ku;Choo, Won-Kook;Moon, Seung-Bin
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.48 no.3
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    • pp.46-53
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    • 2011
  • This paper proposes a SURF (Speeded Up Robust Features) based face recognition method which is one of typical interest point extraction algorithms. In general, SURF based object recognition is performed in interest point extraction and matching. In this paper, although, proposed method is employed not only in interest point extraction and matching, but also in face image rotation and interest point verification. image rotation is performed to increase the number of interest points and interest point verification is performed to find interest points which were matched correctly. Although proposed SURF based face recognition method requires more computation time than PCA based one, it shows better recognition rate than PCA algorithm. Through this experimental result, I confirmed that interest point extraction algorithm also can be adopted in face recognition.

A Study on the Selection for View Target and View Points of Townscape Planning in Chung-ju City (충주시 경관계획 수립을 위한 조망대상 및 조망점 선정에 관한 연구;거주기간을 포함한 사용자 특성을 중심으로)

  • Lee, Yun-Jeong;Bak, Ji-Ae;Kim, Gi-Soo
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.253-259
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    • 2006
  • Since townscape planning zones were introduced in 2000 by a revised Urban Planning Law, interest and understanding on townscape have been enhanced in Korea. Driven by this trend of the time, interest in townscape planning has been growing in the area of urban planning, and local governments have been expressing their interest in townscape management. This study is intended to provide criteria for setting goals of constructing desirable urban environments in harmony with existing condition in Chung-ju City. To this end, questionnaire surveys and awareness research were administered and following findings were obtained in relation to user-specific preferences on view targets and view points for townscape planning in Chung-ju City. In general, citizens of Chung-ju City were found to prefer townscape frequently in use practically, while residents in other areas preferred such townscape as linked with the city' s overall reputation. Both groups were found to prefer natural landscape (Gaemyeongsan, Namsan, etc.) to artificial one as a view target, and Chung-ju Terminal and the neighborhoods and downtown(Seongseo-dong) were presumably preferred as a view point.

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The privacy protection algorithm of ciphertext nearest neighbor query based on the single Hilbert curve

  • Tan, Delin;Wang, Huajun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.9
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    • pp.3087-3103
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    • 2022
  • Nearest neighbor query in location-based services has become a popular application. Aiming at the shortcomings of the privacy protection algorithms of traditional ciphertext nearest neighbor query having the high system overhead because of the usage of the double Hilbert curves and having the inaccurate query results in some special circumstances, a privacy protection algorithm of ciphertext nearest neighbor query which is based on the single Hilbert curve has been proposed. This algorithm uses a single Hilbert curve to transform the two-dimensional coordinates of the points of interest into Hilbert values, and then encrypts them by the order preserving encryption scheme to obtain the one-dimensional ciphertext data which can be compared in numerical size. Then stores the points of interest as elements composed of index value and the ciphertext of the other information about the points of interest on the server-side database. When the user needs to use the nearest neighbor query, firstly calls the approximate nearest neighbor query algorithm proposed in this paper to query on the server-side database, and then obtains the approximate nearest neighbor query results. After that, the accurate nearest neighbor query result can be obtained by calling the precision processing algorithm proposed in this paper. The experimental results show that this privacy protection algorithm of ciphertext nearest neighbor query which is based on the single Hilbert curve is not only feasible, but also optimizes the system overhead and the accuracy of ciphertext nearest neighbor query result.

Influence of Subjective Oral Health Interest and Recognition in Academic Boys' High School Students upon Oral Health Practice in Some Regions (일부지역 인문계 남자고등학생의 주관적 구강건강관심도와 인지도가 구강건강실천에 미치는 영향)

  • Lee, Hyun-Ok;Chun, Ju-Yean
    • Journal of dental hygiene science
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    • v.11 no.1
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    • pp.1-6
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    • 2011
  • The purpose of this study was to offer information in order to induce and practice forming right oral health habit by grasping oral health practice according to subjective oral health interest and recognition in Academic Boys' High School students. Targeting students of Academic Boys' High School where is located in Jeollabuk-do from May 20, 2010 to June 20, the self-administered questionnaire survey was carried out by convenience sampling. The following are the results that the collected data was carried out statistical analysis by using SPSS 12.0 program. 1. Among factors of oral health practice according to oral health interest level, toothbrushing was the highest with 3.89 points. It was in order of education and interest with 3.18 points, diet control with 2.93 points, a regular visit with 2.69 points, and the practice of oral hygiene device with 2.12 points. 2. Among factors of oral health practice according to subjective oral health recognition level, toothbrushing was the highest with 3.89 points. It was in order of education and interest with 3.17 points, diet control with 2.93 points, a regular visit with 2.69 points, and the practice of oral hygiene device with 2.12 points. 3. In correlation between subjective oral health recognition level and oral health practice factor, the more recognition of being healthy in the subjective oral health recognition level led to the higher oral health practice level(p<0.01). 4. As for influence of oral health practice factor upon subjective oral health recognition level, the subjective oral health recognition was high in a group of practicing toothbrushing(p<0.01) and of visiting dental clinic regularly(p<0.05).