• 제목/요약/키워드: Polynomial regression equation

검색결과 59건 처리시간 0.035초

부영양상태 호수유역의 강우유출수에 의한 초기세척효과 분석 (An Analysis on the First Flush Phenomenon by Stormwater Runoff in Eutrophic Lake Watershed)

  • 조재현;서형준
    • 환경영향평가
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    • 제16권5호
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    • pp.341-350
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    • 2007
  • Lake Youngrang is a lagoon whose effluent flows into the East Sea. Because two resort towns and two golf courses are situated at the lake basin, many tourists visit this area. Stormwater runoff surveys were carried out for the eight storm events from 2004 to 2005 in the eutrophic lake watershed to give a basic data for the diffuse pollution control of the lake. Dimensionless mass-volume curves indicating the distribution of pollutant mass vs. volume were used to analyze the first flush phenomenon. The mass-volume curves were fitted with a power function and polynomial equation curves. The regression analysis showed that the polynomial equation curves were better than the power function in representing the tendency of the first flush, and second degree polynomial equation curves indicated the strength of the first flush effectively.

전대수 다항식형 확률강우강도식의 최적차수 결정 및 회귀계수에 대한 유의성 검정 (Determination of optimal order for the full-logged I-D-F polynomial equation and significance test of regression coefficients)

  • 박진희;이재준
    • 한국수자원학회논문집
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    • 제55권10호
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    • pp.775-784
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    • 2022
  • 본 연구에서는 임의지속기간의 확률강우량 산정을 위해 실무에서 주로 사용되고 있는 전대수 다항식형 확률강우강도식의 최적차수 결정을 위하여 경상북도 내 9개 지점을 대상으로 확률강우량을 산정하고 전대수 다항식형 강우강도식의 회귀계수를 추정하였다. 추정된 지점별 다항식을 대상으로 단계선택법을 이용하여 각 지점별 다항식의 최적변수를 선정하고 선정된 변수들의 통계적 유의성을 검토하기 위하여 분산분석을 통한 유의성 검정을 실시하였으며, 이들 결과를 이용하여 각 지점별 통계적으로 적절하게 산정된 강우강도식을 제시하였다. 경북 9개 지점의 전대수 다항식형 강우강도식의 변수선정 결과는 6개 지점에서 1~3차식이 최적식으로 나타났고 1개 지점이 불완전 3차식이 최적식으로 나타났다. 그 중 1차는 Sherman 식, 2차는 General 식의 형태와 유사하므로 독립변수의 수를 증가시켜 적합도를 높이고 사용 편의를 위해 통일된 형태의 강우강도식으로 제시한다면 전대수 다항식형 강우강도식은 3차 회귀식까지만 고려하여도 통계학적으로 문제가 없는 것으로 판단된다.

설계강우량의 Huff 4분위 방법 다항회귀식에 대한 유의성 검정 (Statistical significance test of polynomial regression equation for Huff's quartile method of design rainfall)

  • 박진희;이재준;이성호
    • 한국수자원학회논문집
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    • 제51권3호
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    • pp.263-272
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    • 2018
  • 수공구조물 설계시 실측 유량의 자료 부족으로 홍수량의 빈도해석 결과보다는 강우자료를 수집하여 강우-유출 관계에 따라 산정된 설계강우량을 이용하여 특정 빈도에 해당하는 설계 홍수량을 사용하는 것이 일반적이다. 과거에는 첨두유량 산정을 위하여 합리식과 같은 경험식을 이용하였으나 지속기간이 장기화됨에 따라 실제 사상과는 다른 유출양상이 나타나게 되므로 확률강우량 시간분포의 정확성이 중요하게 되었다. 현재 실무에서는 설계강우량의 시간분포 방법으로 Huff의 4분위 방법 중 3분위를 사용하고 있으며 분위별 곡선에 대한 회귀식은 지속기간 전반에 걸쳐 정확도가 높은 이유로 6차식을 적용하고 있다. 그러나 통계 모델링에서는 간결함의 원리에 따라 회귀식이 간결할 필요가 있으며, 통계적 유의수준에 기초하여 회귀계수를 결정할 필요가 있다. 따라서 본 연구에서는 기상청 관할 69개 강우관측지점을 대상으로 설계강우량의 시간분포 방법으로 사용되고 있는 Huff 4분위 방법의 시간분포 회귀식에 대한 유의성 검정을 실시하였다. 기상청 관할 69개 강우관측지점의 Huff 4분위 방법의 시간분포 회귀식의 유의성 검정결과 대부분의 지점에서 4차식까지 회귀계수가 유의한 것으로 나타나 통계학적으로 Huff의 4분위 방법의 시간분포 회귀식은 4차까지만 고려하여도 무방한 것으로 분석되었다.

임신기간 및 자궁저높이를 이용한 신생아 체중 예측 (Prediction of Newborn Birthweight by the Measurement of Fundal Height and Gestational Period)

  • 조문숙;박영숙
    • 모자간호학회지
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    • 제1권
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    • pp.34-44
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    • 1991
  • The purposes of this study were to predict newborn birthweight by use of gestational period and fundal height and to identify growth curve of fundal height according to gestational period and growth curve of newborn birthweight according to fundal height. The subjects for the study were 802 women who delivered the normal newborn babies at Seoul National University Hospital from Sep. 1, 1981 to Aug.31, 1986. The data were collected bit chart review and analyzed nth SPSS program. The results of study were as follows : 1. The multiple regression equation ($R^2$=0.416) used for the prediction of newborn birthweight was y=(newborn birthweight, kg)=-4.421+0.075$x_1$(fundal height, cm)+0.053$x_2$(gestational period, weeks)+0.016$x_3$(abdominal girth, cm)+0.010$x_4$(maternal height, cm) 2. The growth curve of fundal height according to gestational period was obtained by polynomial regression. The regression equation was Y(fundal height, cm)=-36.78+18.58$log_ex$(gestational period, weeks) The growth curve of newborn birth weight according to fundal height was obtained by polynomial regression. The regression equation was Y(newborn birthweight, kg)=-8.09+3.27$log_ex$ (Fundal Height, cm) 3. In the following subgroups no significant difference was found in fundal height : engaged vs. nonengaged presentation, and nulliparous vs. multiparous women.

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Excel의 추세선을 이용한 표준곡선 검증 (Standard Curve Validation using Trendlines in Excel)

  • 이경화;박형기;신영만
    • 핵의학기술
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    • 제20권2호
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    • pp.69-74
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    • 2016
  • Insulin 83건을 검사 대상으로, 장비 WIZARD(PerkinElmer, USA)와 DREAM- G-10(Shinjin, KOREA)의 Graph Algorithm 중에 표준곡선과 신뢰성이 가장 높은 Excel의 추세선은 다항식 추세선이다. 다음으로 다항식 추세선식을 이용하여 표준농도 1개씩을 제외하여 표준농도의 회귀식에 미치는 영향을 비교한 결과 최고농도($315{\mu}IU/m{\ell}$)의 평균값이 표준물질 6개로 실시한 표준 회귀식을 이용한 평균값과 비교하여 49%나 평균값이 저하되었다. 단 낮은 농도에서는 영향이 미비하였다. 마지막으로 WIZARD의 Point to Point형식과 DREAM G-10의 Point to Point형식이 적합성이 높고, DREAM G-10(Point to Point)와 Excel 다항식 추세선이 적합성이 높으며, Excel 다항식 추세선과 DREAM G-10(2'nd order Polynomial)의 적합성이 높다.

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GMDH 알고리즘과 다항식 퍼지추론에 기초한 퍼지 다항식 뉴럴 네트워크 (Fuzzy Polynomial Neural Networks based on GMDH algorithm and Polynomial Fuzzy Inference)

  • 박호성;윤기찬;오성권
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2000년도 춘계학술대회 학술발표 논문집
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    • pp.130-133
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    • 2000
  • In this paper, a new design methodology named FNNN(Fuzzy Polynomial Neural Network) algorithm is proposed to identify the structure and parameters of fuzzy model using PNN(Polynomial Neural Network) structure and a fuzzy inference method. The PNN is the extended structure of the GMDH(Group Method of Data Handling), and uses several types of polynomials such as linear, quadratic and modified quadratic besides the biquadratic polynomial used in the GMDH. The premise of fuzzy inference rules defines by triangular and gaussian type membership function. The fuzzy inference method uses simplified and regression polynomial inference method which is based on the consequence of fuzzy rule expressed with a polynomial such as linear, quadratic and modified quadratic equation are used. Each node of the FPNN is defined as fuzzy rules and its structure is a kind of neuro-fuzzy architecture Several numerical example are used to evaluate the performance of out proposed model. Also we used the training data and testing data set to obtain a balance between the approximation and generalization of proposed model.

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Identification of Fuzzy Systems by means of the Extended GMDH Algorithm

  • Park, Chun-Seong;Park, Jae-Ho;Oh, Sung-Kwun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.254-259
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    • 1998
  • A new design methology is proposed to identify the structure and parameters of fuzzy model using PNN and a fuzzy inference method. The PNN is the extended structure of the GMDH(Group Method of Data Handling), and uses several types of polynomials such as linear, quadratic and cubic besides the biquadratic polynomial used in the GMDH. The FPNN(Fuzzy Polynomial Neural Networks) algorithm uses PNN(Polynomial Neural networks) structure and a fuzzy inference method. In the fuzzy inference method, the simplified and regression polynomial inference methods are used. Here a regression polynomial inference is based on consequence of fuzzy rules with a polynomial equations such as linear, quadratic and cubic equation. Each node of the FPNN is defined as fuzzy rules and its structure is a kind of neuro-fuzzy architecture. In this paper, we will consider a model that combines the advantage of both FPNN and PNN. Also we use the training and testing data set to obtain a balance between the approximation and generalization of process model. Several numerical examples are used to evaluate the performance of the our proposed model.

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수정된 GMDH 알고리즘 기반 다층 퍼지 추론 시스템에 관한 연구 (A Study on Multi-layer Fuzzy Inference System based on a Modified GMDH Algorithm)

  • 박병준;박춘성;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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    • pp.675-677
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    • 1998
  • In this paper, we propose the fuzzy inference algorithm with multi-layer structure. MFIS(Multi-layer Fuzzy Inference System) uses PNN(Polynomial Neural networks) structure and the fuzzy inference method. The PNN is the extended structure of the GMDH(Group Method of Data Hendling), and uses several types of polynomials such as linear, quadratic and cubic, as well as the biquadratic polynomial used in the GMDH. In the fuzzy inference method, the simplified and regression polynomial inference methods are used. Here, the regression polynomial inference is based on consequence of fuzzy rules with the polynomial equations such as linear, quadratic and cubic equation. Each node of the MFIS is defined as fuzzy rules and its structure is a kind of neuro-fuzzy structure. We use the training and testing data set to obtain a balance between the approximation and the generalization of process model. Several numerical examples are used to evaluate the performance of the our proposed model.

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퍼지 활성 노드를 가진 퍼지 다항식 뉴럴 네트워크 (Fuzzy Polynomial Neural Networks with Fuzzy Activation Node)

  • 박호성;김동원;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2946-2948
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    • 2000
  • In this paper, we proposed the Fuzzy Polynomial Neural Networks(FPNN) model with fuzzy activation node. The proposed FPNN structure is generated from the mutual combination of PNN(Polynomial Neural Networks) structure and fuzzy inference system. The premise of fuzzy inference rules defines by triangular and gaussian type membership function. The fuzzy inference method uses simplified and regression polynomial inference method which is based on the consequence of fuzzy rule expressed with a polynomial such as linear, quadratic and modified quadratic equation are used. The structure of FPNN is not fixed like in conventional Neural Networks and can be generated. The design procedure to obtain an optimal model structure utilizing FPNN algorithm is shown in each stage. Gas furnace time series data used to evaluate the performance of our proposed model.

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