• 제목/요약/키워드: regression analysis equation

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다중회귀분석을 이용한 ALC 경도예측에 관한 연구 (ALC(Autoclaved Lightweight Concrete) Hardness Prediction by Multiple Regression Analysis)

  • 김광수;백승훈;정순석
    • 벤처창업연구
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    • 제7권2호
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    • pp.101-111
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    • 2012
  • ALC(Autoclaved lightweight concrete) 제조공정 중에서 예비양생이 완료된 반 경화제품(cake)인 상태에서 탈형을 실시할 때 적절한 탈형 시기가 지난 후에 탈형을 하게 되면 보습력이 떨어지고 절단 시 피아노선이 절단되어 제품에 균열이 발생할 우려가 있다. 이에 본 연구에서는 탈형 시기의 관리기준이 되는 경도(hardness)에 관한 예측을 하기 위해 관련된 변수들 간에 상호관련성을 찾고자 다중회귀분석(multiple regression analysis)을 이용한 연구를 진행하였다. ALC 제조공정의 V/T(Vibration Time)대기, V/T동작, 발포 높이, 경화시간, 타설 온도, Rising, C/S비의 독립변수(Independent variables)들이 종속변수(Dependent variables)인 경도(hardness)에 어떠한 관련성이 있는지를 다중 회귀분석을 이용한 연구를 진행하였다.

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회귀분석을 이용한 합리적인 교육시설물 점검시간의 산정 기준 도출에 관한 연구 (A Study on Deduction of Reasonable Inspection Time in Educational Facilities Based on Regression Analysis)

  • 석현수;조창연;김재온;손재호
    • 교육시설
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    • 제14권4호
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    • pp.34-42
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    • 2007
  • The investment of BTL(Build-Transfer-Lease) projects for the educational facilities has been increased since 2005. However, many trial errors and problems have been occurring due to the lack of inspection criteria in maintenance cost for the lift cycle of the facilities. Thus, purpose of this study is to derive regression equation for the daily inspection and the regular inspection through analysis of CAD data in order to set the inspection criteria. It is possible to calculate economical maintenance cost of BTL project in educational facilities using criteria of inspection time through the regression equation developed in this study.

초음파 속도법에 의한 현장 콘크리트 강도추정의 신뢰성 향상 (Reliability Improvement of In-Place Concreter Strength Prediction by Ultrasonic Pulse Velocity Method)

  • 원종필;박성기
    • 한국농공학회지
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    • 제43권4호
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    • pp.97-105
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    • 2001
  • The ultrasonic pulse velocity test has a strong potential to be developed into a very useful and relatively inexpensive in-place test for assuring the quality of concrete placed in structure. The main problem in realizing this potential is that the relationship between compressive strength ad ultrasonic pulse velocity is uncertain and concrete is an inherently variable material. The objective of this study is to improve the reliability of in-place concrete strength predictions by ultrasonic pulse velocity method. Experimental cement content, s/a rate, and curing condition of concrete. Accuracy of the prediction expressed in empirical formula are examined by multiple regression analysis and linear regression analysis and practical equation for estimation the concrete strength are proposed. Multiple regression model uses water-cement ratio cement content s/a rate, and pulse velocity as dependent variables and the compressive strength as an independent variable. Also linear regression model is used to only pulse velocity as dependent variables. Comparing the results of the analysis the proposed equation expressed highest reliability than other previous proposed equations.

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열간금형용강의 고속 엔드밀 가공인자의 영향에 대한 통계적 분석의 적용 (Application of Statistical Analysis for Working Factors Effect of High Speed End-Milling for STD61)

  • 배효준;이상재;우규성;박흥식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1148-1153
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    • 2004
  • Recently the high speed end-milling processing is demanded the high-precise technique with good surface rougj1ness and rapid time in aircraft, automobile part and molding industry. The working factors of high speed end-milling has an effect on surface roughness of cutting surface. Therefore this study was carried out to analyze the working factors to get the optimum surface roughness by design of experiment. From this study, surface roughness have an much effect according to priority on Spindle speed, feed rale, hardness and axial depth of cut By design of experiment, it is effectively represented shape characteristics of surface roughness in high speed end-milling And determination($R^2$) coefficient of regression equation had a satisfactory reliability of 89.7% and regression equation of surface roughness is made by regression analysis.

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마이크로 엔드밀 가공시 가공인자가 표면거칠기 향상에 미치는 영향 (Effects of Machining Conditions for Improvement of Surface Roughness on Micro End-Milling)

  • 조병무;김상진;박희상;배명일
    • 한국공작기계학회논문집
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    • 제17권2호
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    • pp.71-76
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    • 2008
  • Micro end-milling is one of effective technology that is able to do ultra-precision machining while increasing the productivity and has wide application field. But selection of machining condition is very difficult because of complicated machining mechanism. Therefore this study was carried out to select working factors to get the optimum surface roughness. Machining condition are depth of cut, feed rate and spindle revolution. The result of this study showed that Surface roughness was affected, in the other of depth of cut, spindle revolution, feed rate. And this study provided an regression equation relating surface roughness to working factors through Regression Analysis and determination coefficient of regression equation had a satisfactory reliability of 79%.

엔드밀 고속 가공시 표면정도 향상을 위한 가공인자의 영향 분석 (Analysis of Working Factors for Improvement of Surface Roughness on High Speed End-Milling)

  • 배효준;박흥식
    • 한국정밀공학회지
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    • 제21권6호
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    • pp.52-59
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    • 2004
  • Recently the high speed end-milling processing is demanded the high-precise technique with good surface roughness and rapid time in aircraft, automobile part and molding industry. The working factors of high speed end-milling has an effect on surface roughness of cutting surface. Therefore this study was carried out to analyze the working factors to get the optimum surface roughness by design of experiment. From this study, surface roughness have an much effect according to priority on distance of cut, feed rate, revolution of spindle and depth of cut. By design of experiment, it is effectively represented shape characteristics of surface roughness in high speed end-milling. And determination($R^2$) coefficient of regression equation had a satisfactory reliability of 76.3% and regression equation of surface roughness is made by regression analysis.

Penman 식과 기상요소를 이용한 증발산모델에 관하여 (On the Evapotranspiration Model derived from the Meteorological Elements and Penman equation)

  • 이광호
    • 물과 미래
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    • 제6권2호
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    • pp.6-11
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    • 1973
  • This paper include the hydrometeorological analyses of evapotranspiration which is import factor concerning the estimate of water budgest over a certain basin. Evapotranspiration model mode by the multiple regression analysis between the evapotranspiration measured on various kinds of ground cover (water, bare soil and lawn) and the other meteorological elements affecting the evapotranspiration process, and the simple regression analysis between the evapo transpiration measured on each ground cover and the evapotranspiration on water and vegetables calculated from the Penman equation. It is expected that the evapotranspiration models are a very useful formulae estimating ten days amounts or a month's amounts.

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Relationship between porcine carcass grades and estimated traits based on conventional and non-destructive inspection methods

  • Lim, Seok-Won;Hwang, Doyon;Kim, Sangwook;Kim, Jun-Mo
    • Journal of Animal Science and Technology
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    • 제64권1호
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    • pp.155-165
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    • 2022
  • As pork consumption increases, rapid and accurate determination of porcine carcass grades at abattoirs has become important. Non-destructive, automated inspection methods have improved slaughter efficiency in abattoirs. Furthermore, the development of a calibration equation suitable for non-destructive inspection of domestic pig breeds may lead to rapid determination of pig carcass and more objective pork grading judgement. In order to increase the efficiency of pig slaughter, the correct estimation of the automated-method that can accommodate the existing pig carcass judgement should be made. In this study, the previously developed calibration equation was verified to confirm whether the estimated traits accord with the actual measured traits of pig carcass. A total of 1,069,019 pigs, to which the developed calibration equation, was applied were used in the study and the optimal estimated regression equation for actual measured two traits (backfat thickness and hot carcass weight) was proposed using the estimated traits. The accuracy of backfat thickness and hot carcass weight traits in the estimated regression models through stepwise regression analysis was 0.840 (R2) and 0.980 (R2), respectively. By comparing the actually measured traits with the estimated traits, we proposed optimal estimated regression equation for the two measured traits, which we expect will be a cornerstone for the Korean porcine carcass grading system.

다중회귀분석을 통한 대구지역 오존농도 예측 (Prediction of Ozone Concentration by Multiple Regression Analysis in Daegu area)

  • 최성우;최상기;도상현
    • 한국환경과학회지
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    • 제11권7호
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    • pp.687-696
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    • 2002
  • Air quality monitoring data and meteorology data which had collected from 1995. 1. to 1999. 2. in six areas of Daegu, Manchondong, Bokhyundong, Deamyungdong, Samdukdong, Leehyundong and Nowondong, were investigated to determine the distribution and characteristic of ozone. A equation of multiple regression was suggested after time series analysis of contribution factor and meteorology factor were investigated during the day which had high concentration of ozone. The results show the following; First, 63.6% of high ozone concentration days, more than 60 ppb of ozone concentration, were in May, June and September. The percentage of each area showed that; Manchondong 14.4%, Bokhyundong 15.4%, Deamyungdong 15.6%, Samdukdong 15.6%, Leehyundong 17.3% and Nowondong 21.6%. Second, correlation coefficients of ozone, $SO_2$, TSP, $NO_2$ and CO showed negative relationship; the results were respectively -0.229, -0.074, -0.387, -0.190(p<0.01), and humidity were -0.677. but temperature, amount of radiation and wind speed had positive relationship; the results were respectively 0.515, 0.509, 0.400(p<0.01). Third, $R^2$ of equation of multiple regression at each area showed that; Nowondong 45.4%, Lee hyundong 77.9%, Samdukdong 69.9%, Daemyungdong 78.8%, Manchondong 88.6%, Bokhyundong 77.6%. Including 1 hour prior ozone concentration, $R^2$ of each area was significantly increased; Nowondong 75.2%, Leehyundong 89.3%, Samdukdong 86.4%, Daemyungdong 88.6%, Manchondong 88.6%, Bokhyundong 88.0%. Using equation of multiple regression, There were some different $R^2$ between predicted value and observed value; Nowondong 48%, Leehyundong 77.5%, Samdukdong 58%, Daemyungdong 73.4%, Manchondong 77.7%, Bokhyundong 75.1%. $R^2$ of model including 1 hour prior ozone concentration was higher than equation of current day; Nowondong 82.5%, Leehyundong 88.3%, Samdukdong 80.7%, Daemyungdong 82.4%, Manchondong 87.6%, Bokhyundong 88.5%.

통계적 기법을 적용한 헬기 형상설계 연구 (A Study of Helicopter Initial Sizing using Statistical Methodology)

  • 김준모;오우섭
    • 한국군사과학기술학회지
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    • 제10권1호
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    • pp.22-32
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    • 2007
  • This paper describes a study of a helicopter database for the sizing stage of a preliminary design process. The database includes specifications and performance parameters for more than 150 conventional single rotor helicopters currently in market. Design parameters, including configuration and weight parameters, have been analyzed and trend curve equations(regression equations) are derived using the regression analysis method. Finally, the applicability of this research result was verified whether the method is reliable for being adopted as a useful design tool in the early stage of a helicopter design process.