• Title/Summary/Keyword: knot data

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Pliable regression spline estimator using auxiliary variables

  • Oh, Jae-Kwon;Jhong, Jae-Hwan
    • Communications for Statistical Applications and Methods
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    • v.28 no.5
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    • pp.537-551
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    • 2021
  • We conducted a study on a regression spline estimator with a few pre-specified auxiliary variables. For the implementation of the proposed estimators, we adapted a coordinate descent algorithm. This was implemented by considering a structure of the sum of the residuals squared objective function determined by the B-spline and the auxiliary coefficients. We also considered an efficient stepwise knot selection algorithm based on the Bayesian information criterion. This was to adaptively select smoothly functioning estimator data. Numerical studies using both simulated and real data sets were conducted to illustrate the proposed method's performance. An R software package psav is available.

The Caracteristics of Traditional Dyeing and Patterns on Turkish Carpets (터키지역 전통염색 카페트의 문양 특성)

  • 신정숙
    • Journal of the Korea Fashion and Costume Design Association
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    • v.6 no.1
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    • pp.34-45
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    • 2004
  • The purpose of the study was to investigate weaving, traditional dyeing, fiber material, pattern how carpet developing according to Turkey area for using the data that can rear to the export strategic industry for carpet production and development that is correct in culture. The result are followed: 1) Life of the age was expressed in color and pattern using according to geographical environment, climate, lifestyle, religion etc. 2) In the case of weaving, there is Kilim, Soumak that appears only weft on the surface as plane weaving without knot and carpet of knotted pile weaving and knot of carpet is duplex knot difference with carpet of the other country. 3) In the case of textile material, there is use most wool fiber that can get easily from breeded sheep by nomads. 4) In the case of dyeing, did the local traditional color to use dye extracting in dyeing material that can get easily in the area. Red that can extract in madder that can get easily in which area of Turkey, dark navy blue of indigo dye that indigo plant fermentation and cream beige that is wool's natural color were exposed representative traditional color of Turkey carpet. 5) Pattern was advanced uniquely as culture of the area; weaving person's sensitivity and desire are reflected through centuries. Amulet, riches & honors, fecundity and happiness appeared most pattern in any area.

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Estimating dose-response curves using splines: a nonparametric Bayesian knot selection method

  • Lee, Jiwon;Kim, Yongku;Kim, Young Min
    • Communications for Statistical Applications and Methods
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    • v.29 no.3
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    • pp.287-299
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    • 2022
  • In radiation epidemiology, the excess relative risk (ERR) model is used to determine the dose-response relationship. In general, the dose-response relationship for the ERR model is assumed to be linear, linear-quadratic, linear-threshold, quadratic, and so on. However, since none of these functions dominate other functions for expressing the dose-response relationship, a Bayesian semiparametric method using splines has recently been proposed. Thus, we improve the Bayesian semiparametric method for the selection of the tuning parameters for splines as the number and location of knots using a Bayesian knot selection method. Equally spaced knots cannot capture the characteristic of radiation exposed dose distribution which is highly skewed in general. Therefore, we propose a nonparametric Bayesian knot selection method based on a Dirichlet process mixture model. Inference of the spline coefficients after obtaining the number and location of knots is performed in the Bayesian framework. We apply this approach to the life span study cohort data from the radiation effects research foundation in Japan, and the results illustrate that the proposed method provides competitive curve estimates for the dose-response curve and relatively stable credible intervals for the curve.

ECG signal compression based on B-spline approximation (B-spline 근사화 기반의 심전도 신호 압축)

  • Ryu, Chun-Ha;Kim, Tae-Hun;Lee, Byung-Gook;Choi, Byung-Jae;Park, Kil-Houm
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.653-659
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    • 2011
  • In general, electrocardiogram(ECG) signals are sampled with a frequency over 200Hz and stored for a long time. It is required to compress data efficiently for storing and transmitting them. In this paper, a method for compression of ECG data is proposed, using by Non Uniform B-spline approximation, which has been widely used to approximation theory of applied mathematics and geometric modeling. ECG signals are compressed and reconstructed using B-spline basis function which curve has local controllability and control a shape and curve in part. The proposed method selected additional knot with each step for minimizing reconstruction error and reduced time complexity. It is established that the proposed method using B-spline approximation has good compression ratio and reconstruct besides preserving all feature point of ECG signals, through the experimental results from MIT-BIH Arrhythmia database.

The Degree Reduction of B-splines using Bzier Methods (Bzier 방법을 이용한 B-spline의 차수 감소)

  • Kim, Hyeok-Jin;Kim, Tae-Wan;Wi, Yeong-Cheol;Kim, Ha-Jin
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.8
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    • pp.875-883
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    • 1999
  • 서로 다른 기하학적 모델링 시스템에 사용되는 곡선 및 곡면의 자료 교환에서, 시스템이 지원하는 그 곡선 및 곡면의 최대 차수에 제한이 있을 때, 낮은 차수로의 차수 감소가 필요하다. 본 논문에서는 근사 변환에 의한 B-spline 곡선의 차수 감소 방법을 제시한다. 기존의 Bzier 곡선의 차수감소 방법들을 적용하고, 그 방법들을 비교 분석한다. B-spline 곡선의 knot 제거 알고리즘이 자료 감소를 위해 차수 감소 과정에 적용된다.Abstract The degree reduction of B-splines is required in exchanging parametric curves and surfaces of the different geometric modeling systems because some systems limit the supported maximal degree. We propose an approximate degree reduction method of B-spline curves using the existing Bzier degree reduction methods. Knot removal algorithm is used to reduce data in the degree reduction process.

Approximate Lofting by B-spline Curve Fitting Based on Energy Minimization (에너지 최소화에 근거한 B-spline curve fitting을 이용한 근사적 lofting 방법)

  • 박형준;김광수
    • Korean Journal of Computational Design and Engineering
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    • v.4 no.1
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    • pp.32-42
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    • 1999
  • Approximate lofting or skinning is one of practical surface modeling techniques well used in CAD and reverse engineering applications. Presented in this paper is a method for approximately lofting a given set of curves wihin a specified tolereance. It is based on refitting input curves simultaneously on a common knot vector and interpolating them to get a resultant NURBS surface. A concept of reducing the number of interior knots of the common knot vector is well adopted to acquire more compact representation for the resultant surface. Energy minimization is newly introduced in curve refitting process to stabilize the solution of the fitting problem and get more fair curve. The proposed approximate lofting provides more smooth surface models and realizes more efficient data reduction expecially when the parameterization and compatibility of input curves are not good enough. The method has been successfully implemented in a new CAD/CAM product VX Vision? of Varimetrix Corporation.

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An Experimental Analysis of Approximate Conversions for B-splines (B-spline에 대한 근사변환의 실험적 분석)

  • Kim Hyeock Jin
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.1 s.33
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    • pp.35-44
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    • 2005
  • The degree reduction of B-splines is necessary in exchanging parametric curves and surfaces of the different geometric modeling systems because some systems limit the supported maximal degree. In this paper, We provide an our experimental results in approximate conversion for B-splines apply to degree reduction. We utilize the existing Bezier degree reduction methods, and analyze the methods. Also, knot removal algorithm is used to reduce data in the degree reduction Process.

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Approximate conversion using the degree reduction of NURBS (NURBS의 차수 감소 방법을 이용한 근사변환)

  • 김혁진
    • Journal of the Korea Society of Computer and Information
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    • v.8 no.1
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    • pp.7-12
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    • 2003
  • Because some systems limit the supported maximal degree, the degree reduction of NURBS is necessary in Parametric curves and surfaces of the different geometric modeling systems. Therefore an approximate degree reduction method of NURBS curves was introduced in this research. Also the existing Eck's B$\'{e}$zier degree reduction method and knot removal algorithm were used to reduce data in the degree reduction process. Finally we found that this method was stable, efficient for implementations, and easy to use algorithms.

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Effects of Pruning on Timber Quality of Pinus koraiensis Grown in Korea

  • Chong, Song-Ho;Jung, Doo-Jin;Park, Byung-Su;Chun, Su Kyoung
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.6
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    • pp.22-30
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    • 2003
  • This study was performed to obtain the basic data for high quality timber production and efficient utilization by investigating the effect of pruning on timber quality of domestic plantation-grown Korean pine (Pinus koraiensis Sieb. et Zucc.). The results were summarized as follows:Dead knots (unsound knots) in the pruned logs occurred more at upper parts when compared with in non-pruned ones. The numbers of knots on surface in heavily pruned trees were less than those in non-pruned trees, but there was no significant difference in moderately pruned trees. The required period to reveal clear timber surface without defects after pruning increased proportionally with the increase of knot diameter. The yield of clear lumber production increased by about 10% after 14 years from moderate pruning. The quality grade of log improved with more pruning practices. Knots appeared the most important factor in lowering the log grades.

The Experience of Hospice Nurses on Spiritual Care: The Process of Untying a Knot of Mind (호스피스병동 간호사의 영적간호경험: 마음의 매듭 풀어주기 과정)

  • Kang, Sung-Ye;Koh, Moon-Hee;Choi, Jeong-Sook
    • Asian Oncology Nursing
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    • v.8 no.2
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    • pp.111-119
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    • 2008
  • Purpose: The purpose of this study was to describe the experience of hospice nurses on spiritual care. Methods: Data was collected from 9 hospice nurses by using in-depth interview. The main questions include what they understand as spiritual care, when they feel the needs of spiritual care, how they perform spiritual care, and what is the outcome of spiritual care. The data was analyzed by grounded theory methodology developed by Strauss and Corbin. Results: The core category of experience of hospice nurses on spiritual care was identified as "Untie a knot of mind". In the process of spiritual care in hospice nurses was consisted of soothing, dwelling with, releasing, giving meaning, plunging, and going beyond a life. Conclusion: The result of this study was expected to give useful information to nurses and nursing managers about the real situation of performance of spiritual care. The findings of this study contributes to developing programs and supportive policies for encouraging spiritual care.

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