• 제목/요약/키워드: The coefficient of determination($R^2$)

검색결과 885건 처리시간 0.03초

DETERMINATION OF MOISTURE AND NITROGEN ON UNDRIED FORAGES BY NEAR INFRARED REFLECTANCE SPECTROSCOPY(NIRS)

  • Cozzolino, D.;Labandera, M.;Inia La Estanzuela
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1620-1620
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    • 2001
  • Forages, both grazed and conserved, provide the basis of ruminant production systems throughout the world. More than 90 per cent of the feed energy consumed by herbivorous animals world - wide were provided by forages. With such world - wide dependence on forages, the economic and nutritional necessity of been able to characterize them in a meaningful way is vital. The characterization of forages for productive animals is becoming important for several reasons. Relative to conventional laboratory procedures, Near Infrared Reflectance Spectroscopy (NIRS) offers advantages of simplicity, speed, reduced chemical waste, and more cost-effective prediction of product functionality. NIR spectroscopy represents a radical departure from conventional analytical methods, in that entire sample of forage is characterized in terms of its absorption properties in the near infrared region, rather than separate subsamples being treated with various chemicals to isolate specific components. This forces the analyst to abandon his/her traditional narrow focus on the sample (one analyte at a time) and to take a broader view of the relationship between components within the sample and between the sample and the population from which it comes. forage is usually analysed by NIRS in dry and ground presentation. Initial success of NIRS analysis of coarse forages suggest a need to better understand the potential for analysis of minimally processed samples. Preparation costs and possible compositional alterations could be reduced by samples presented to the instrument in undried and unground conditions. NIRS has gained widespread acceptance for the analysis of forage quality constituents on dry material, however little attention has been given to the use of NIRS for chemical determinations on undried and unground forages. Relatively few works reported the use of NIRS to determine quality parameters on undried materials, most of them on both grass and corn silage. Only two works have been found on the determination of quality parameters on fresh forages. The objectives of this paper were (1) to evaluate the use of NIRS for determination of nitrogen and moisture on undried and unground forage samples and (2) to explore two mathematical treatments and two NIR regions to predict chemical parameters on fresh forage. Four hundred forage samples (n: 400) were analysed in a NIRS 6500 instrument (NIR Systems, PA, USA) in reflectance mode. Two mathematical treatments were applied: 1,4,4,1 and 2,5,5,2. Predictive equations were developed using modified partial least squares (MPLS) with internal cross - validation. Coefficient of determination in calibration (${R^2}_{CAL}$) and standard error in cross-validation (SECV) for moisture were 0.92 (12.4) and 0.92 (12.4) for 1,4,4,1 and 2,5,5,2 respectively, on g $kg^{-1}$ dry weight. For crude protein NIRS calibration statistics yield a (${R^2}_{CAL}$) and (SECV) of 0.85 (19.8) and 0.85 (19.6) for 1,4,4,1 and 2,5,5,2 respectively, on a dry weight. It was concluded that NIRS is a suitable method to predict moisture and nitrogen on fresh forage without samples preparation.

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Predictive analyses for balance and gait based on trunk performance using clinical scales in persons with stroke

  • Woo, Youngkeun
    • Physical Therapy Rehabilitation Science
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    • 제7권1호
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    • pp.29-34
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    • 2018
  • Objective: This study aimed to predict balance and gait abilities with the Trunk Impairment scales (TIS) in persons with stroke. Design: Cross-sectional study. Methods: Sixty-eight participants with stoke were assessed with the TIS, Berg Balance scale (BBS), and Functional Gait Assessment (FGA) by a therapist. To describe of general characteristics, we used descriptive and frequency analyses, and the TIS was used as a predictive variable to determine the BBS. In the simple regression analysis, the TIS was used as a predictive variable for the BBS and FGA, and the TIS and BBS were used as predictive variables to determine the FGA in multiple regression analysis. Results: In the group with a BBS score of >45 for regression equation for predicting BBS score using TIS score, the coefficient of determination ($R^2$) was 0.234, and the $R^2$ was 0.500 in the group with a BBS score of ${\leq}45$. In the group with an FGA score >15 for regression equation for predicting FGA score using TIS score, the $R^2$ was 0.193, and regression equation for predicting FGA score using TIS score, the $R^2$ was 0.181 in the group of FGA score ${\leq}15$. In the group of FGA score >15 for regression equation for predicting FGA score using TIS and BBS score, the $R^2$ was 0.327. In the group of FGA score ${\leq}15$ for regression equation for predicting FGA score using TIS and BBS score, the $R^2$ was 0.316. Conclusions: The TIS scores are insufficient in predicting the FGA and BBS scores in those with higher balance ability, and the BBS and TIS could be used for predicting variables for FGA. However, TIS is a strong predictive variable for persons with stroke who have poor balance ability.

농지이용계획의 합리적 책정을 위한 농지적성 평가기법의 개발 (Development of Land Suitability Classification System for Rational Agricultural Land Use Planning)

  • 황한철;최수명
    • 농촌계획
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    • 제3권2호
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    • pp.102-111
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    • 1997
  • For rational agricultural land use planning, it is quite necessary to get hold of land suitability precisely and to make decision on land use patterns accordingly. In the methodological viewpoint, objective and scientific evaluation techniques for land suitability classification should be supported for the systematic land use planning. As one of technical development approaches to rational land use planning, this study tried to frame a land suitability evaluation system for agricultural purposes. Evaluation unit is defined as a tract of land bounded by road, other land units and topographical features. And quantification theory was applied in the determination works of evaluation criteria. The administrative area of Namsa-myon(district), Yongin-si(city), Kyunggi-do(province) was selected for the case study. In order to check the feasibility of the evaluation system developed in the study, field check team, consisting of 2 government officers and 2 representative farmers, carried out evaluation works by observation on 148 sample land units, 10% of total 1,480 ones. Between estimated and observed results, there showed very good relationship of its multiple correlation coefficient, R=0.9467.

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유헬스용 요분석기의 정색반응 시스템 개발 (Development of Primary Color Reaction System of Urine Analyzer for U-health)

  • 이상식;박원엽;구지현;이충호
    • 한국정보전자통신기술학회논문지
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    • 제2권2호
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    • pp.9-14
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    • 2009
  • 본 연구에서는 유헬스용 요분석기를 개발하기 위한 선행 연구로서 요분석 스트립의 색변화를 측정할 수 있는 정색반응 전자회로를 개발하였다. 정색반응 시스템은 컴퓨터, 정색반응 전자회로, 트레이장치, 센서조합체 및 소프트웨어로 구성하였다. 요분석 스트립의 색 변화를 측정하기 위하여 칼라센서가 사용되기 때문에, 표준 색상지를 이용하여 칼라센서의 측정값과 RGB값 사이의 선형방정식을 수립하였다. 빨간색(R)의 회귀방정식은 $Red=0.2414{\times}x$(센서 값) - 3.0042($R^2=0.9801$)로 나타났고, 녹색(G)의 회귀방정식은 $Green=0.2857{\times}x$(센서 값) - 6.4251($R^2=0.9868$)로 나타났고, 파란색(B)의 회귀방정식은 $Blue=0.2114{\times}x$(센서 값) - 6.2743($R^2=0.9837$)으로 나타났으므로 표준색상지와 칼라센서는 높은 상관관계가 있는 것을 알 수가 있었다. 정색반응 시스템을 검증하기 위하여 요 성분 중 적혈구, 빌리루빈, 우로빌리노겐, 케톤, 단백질의 5가지 성분에 대하여 각기 다른 농도로 표준시약을 제조하여 정색반응을 측정하였다. 각 시약의 농도에 따른 칼라센서의 정색반응 결과가 통계적으로 타당한 결과를 보였고 유헬스용 요분석기 개발에 적용할 수 있을 것으로 사료된다.

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폐목재로부터 리그닌 추출을 위한 Organosolv 전처리공정의 최적화 (Optimization of Organosolv Pretreatment of Waste Wood for Lignin Extraction)

  • 이현수;김영모
    • 대한환경공학회지
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    • 제39권10호
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    • pp.568-574
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    • 2017
  • 본 연구는 폐목재로부터 organosolv 공정을 이용해서 리그닌을 분리할 때 영향을 미치는 주요 3개의 반응조건(반응시간($X_1$), 산 촉매의 농도($X_2$) 및 반응온도($X_3$))을 리그닌 회수율(y) 기준으로 최적화하였다. 중심합성계획법(central composite design, CCD)에 따라 반응온도 $136.4-203.6^{\circ}C$, 산촉매 농도 0-2.5%, 반응시간 26.36-93.64 분의 범위를 가진 실험계획을 수행해서 2차 모델식 및 최적조건을 수립하였다. 2차 모델식은 $y=-79.89+0.91X_1+9.8X_2-2.54{\times}10^{-3}X_1{^2}-2.11X_2{^2}$와 같이 얻었으며, 결정계수(coefficient of determination, $R^2$) 값은 0.8531으로 10% 이내의 유의수준에서 유의성을 나타냈다. 2차 모델식에 따라 예측되는 최고 리그닌 회수율은 12.46 g/100 g of dry wood이며 이때 최적 반응 조건은 반응온도 $178.2^{\circ}C$, 산 촉매 농도 2.32%으로 나타났다. 폐목재 대상 organosolv 공정에서의 리그닌 수율은 반응온도보다는 산 촉매 농도의 영향이 더 크게 나타났으며 반응시간에 의한 영향은 없는 것으로 나타났다. 모델의 변동성 분석(analysis of variance, ANOVA)에 따르면 리그닌 수율(y)에 대한 모델식의 유의확률은 p<0.001로 높은 유의성을 보였다. 최적조건에서 모델의 재현성을 검증한 결과 모델식이 실제공정을 적절하게 모사한 것으로 나타났다.

역상 HPLC에 의한 Fatty quaternary ammonium salt 4종 동시분석 (Simultaneous determination of Fatty quaternary ammonium salt by RP-HPLC)

  • 이용화;양재찬;김재광;이용섭
    • 한국응용과학기술학회지
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    • 제32권3호
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    • pp.461-468
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    • 2015
  • 역상 HPLC에 의한 Cetyltrimetyl ammonium chloride(CTM), Stearamidopropyl dimetylamine(SAP), Behentriammonium chloride(BHT), Dihexadeyldimethyl ammonium chloride (DHDDM)의 양이온계면활성제 4종 동시 정량분석 방법을 개발하였다. 분석조건으로 분리관은 Alltech $C_{18}$($250mm{\times}4.6mm$ i.d., $5{\mu}m$)을 사용하였고, 검출기는 ELSD를 사용하였으며, 이동상은 0.2% TFA/Methanol의 기울기 용리에 의해 분석되었다. 이때 검량선의 상관계수($r^2$)는 $130{\sim}1980.5{\mu}g/mL$농도 범위에서 0.997이상 이었고, 검출한계, 정밀성이 우수하였다. 이 방법은 fatty quaternary ammonium salt 4종의 정량분석 가능함을 보여 주었다.

요오드이온 생성 및 Methylene Green과의 용매추출에 의한 미량 황이온의 분광광도법 정량 (Spectrophotometric Determination of Trace Amount of Sulfide by Formation of Iodide and Its Solvent Extraction with Mehtylene Green)

  • 감상규;김경연
    • 분석과학
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    • 제7권3호
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    • pp.261-269
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    • 1994
  • 요오드산 이온의 황이온의 산화에 의해 화학양론적으로 형성되는 요오드이온과 methylene green과의 이온쌍을 1,2-dichloroethane으로 추출하여 656nm에서 분광광도법에 의해 황이온의 정량법을 확립하였다. 시료기질로부터 분리되어지는 황화수소는 pH 3.5 초산 완충용액과 요오드산 이온이 포함된 용액에 도입되어 완전히 전환되었다. 황이온의 정량범위는 $3{\times}10^{-7}{\sim}1.2{\times}10^{-5}M$ ($0.0096{\sim}0.384{\mu}g/ml$) 였으며, 검출한계는 $0.0032{\mu}g/ml$였고, 몰흡광계수는 $6.7{\times}10^4L\;mole^{-1}\;cm^{-1}$였다. 본 정량법을 하천수 중에 응용하였을 때 $5{\times}10^{-6}M$ 농도에서 상대표준편차는 1.59%로 미량에서 공존이온의 영향을 거의 받지 않고 재현성 있는 결과를 나타내므로 실시료 중에 효과적으로 응용할 수 있으리라 생각된다.

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Machine Learning Methods to Predict Vehicle Fuel Consumption

  • Ko, Kwangho
    • 한국컴퓨터정보학회논문지
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    • 제27권9호
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    • pp.13-20
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    • 2022
  • 본 연구에서는 주행 차량의 실시간 연료소모량을 예측할 수 있는 머신러닝 기법을 제안하고 그 특성을 분석하였다. 머신러닝 학습을 위해 실도로 주행을 실시하여 주행 속도, 가속도, 도로 구배와 함께 연료소모량을 측정하였다. 특성 데이터로 속도, 가속도, 도로구배를, 타깃으로 연료소모량을 지정하여 다양한 머신러닝 모델을 학습시켰다. 회귀법에 해당하는 K-최근접이웃회귀 및 선형회귀와 함께, 분류법에 해당하는 K-최근접이웃분류, 로지스틱회귀, 결정트리, 랜덤포레스트, 그래디언부스팅을 사용하였다. 실시간 연료소모량에 대한 예측 정확도는 0.5 ~ 0.6 수준으로 전반적으로 낮았고, 회귀법의 경우 분류법보다 정확도가 떨어졌다. 총연료소모량에 대한 예측 오차는 0.2 ~ 2.0% 수준으로 상당히 정확했고, 분류법보다 회귀법의 오차가 더 낮았다. 이는 예측 정확도의 기준으로 결정계수(R2)를 사용했기 때문인데, 이 값이 작을수록 타깃의 평균 부근에 예측치가 좁게 분포하기 때문이다. 따라서 실시간 연료소모량 예측에는 분류법이, 총연료소모량 예측에는 회귀법이 적합하다고 할 수 있다.

일부 농촌주민 혈중 Paraoxonase 활성도의 분포 및 관련인자에 관한 조사연구 (A Study on the Distributions of Paraoxonase Activity and the Factors affecting Paraoxonase Activity of a Rural Population)

  • 송재철;박항배
    • Journal of Preventive Medicine and Public Health
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    • 제23권2호
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    • pp.194-200
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    • 1990
  • The paraoxonase (E. C. 3.1.1.2) is a major enzyme to detoxicate the organophosphorus and carbamate which are the most widely used as the agricultural spraying insecticides. To investgate the distributions of plasma paraoxonase activity and the factors affecting the enzyme activity, the plasmas of 945 Korean rural population were analysed with the modified Krisch's direct sphectrphotometry method. Three indices of the enzyme activity - basal activity, stimulated activity (by NaCl), % stimulation - were obtained from the analysis. Three indicies suggested unimodal distributions, so we couldn't identify the low activity group risk group to organophosphorus & carbamate insecticides poisoning. There is no significant relation between 3 actvity indicies and sex, age, or history of insecticide use (p>0.05). The basal activity and the stimulated activity have significant relationship and high coefficient of determination with the activities of their parents ($r^2$=0.30, 0.24 ; p<0.05), but the % stimulation does not ($r^2$=0.02 ; p<0.05). These results suggest that the activity of paraoxonase is determined mainly by the genetic factor.

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중금속 제거를 위한 흡착제로서 생물산업 폐기물의 재활용 (Recycling of Biological Industrial Waste as an Adsorbent for Heavy Metals)

  • 장재선;이제만;김용희
    • 환경위생공학
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    • 제17권3호
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    • pp.7-13
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    • 2002
  • The removal efficiency of heavy metals by chitosan complex isolated from biological industrial waste was investigated through laboratory experiments. The results of the study are as follows. The adsorption kinetics of heavy metals were reached the equilibrium adsorption in approximately 30 minutes and the removal efficiency were showed 70.7~97.4%. The effect of temperature on heavy metals adsorption by chitosan complex shows that as the temperature increased, the amount of heavy metals adsorption per unit weight of chitosan complex increased. The correlation between amount of heavy metals adsorption per unit weight of chitosan complex and temperature were obtained through the coefficient of determination($R^2$). $R^2$ values were 0.75(p<0.05), 0.99(p<0.05) and 0.98(p<0.05) in Hg, Mn, and Zn, respectively. The injected chitosan complex in which 0.1 g was adsorpted highly and the removal of heavy metals was found to have the best removal efficiency A linearized Freundlich equation was used to fit the acquired experimental data. As a result, Freundlich constants, the adsorption intensity(I/n) was 0.5564, 0.4074, 0.5244 on the Hg, Mn, Zn, respectively And the measure of adsorption(k) was 2.2144, 1.6963, 2.0792 on the Hg, Mn, Zn, respectively. So, it was concluded that adsorption of heavy metals by chitosan complex is effective.