• 상하수도학회지
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• 제20권3호
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• pp.339-343
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• 2006

• 품질경영학회지
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• 제21권1호
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• pp.55-64
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• 1993

This article is concerned with procedures for detecting one or more outliers or influential observations in a linear regression model. A test procedure, based on recursive residuals is proposed and developed The power of the test procedure to identify one or more outliers is investigated through simulation, and its relevance to the number and configuration of the outlier.

• 노동경제논집
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• 제36권2호
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• pp.1-36
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• 2013

본 연구는 임금함수 추정으로부터 얻어진 잔차, 즉 보이지 않는 이질성이 자영업 선택에 어떠한 영향을 미치는지를 살펴본다. Joona and Wadensjo(2013)에 따라 이 잔차를 개인 능력의 대리변수로 간주하고, 과연 능력이 뛰어난 사람이 자영업자가 되는지, 아니면 능력이 낮은 사람이 자영업을 선택하는지를 한국노동패널 1-11차를 이용하여 검증한다. 전체 근로자를 대상으로 할 때 능력의 양극에 있는 사람들이 상대적으로 자영업 진입확률이 높지만, 남녀를 구분할 경우 이러한 U자형의 관계는 존재하지 않으며, 남성의 경우에는 능력이 낮은 사람이, 여성의 경우에는 능력이 높은 사람이 자영업으로 진입한다는 것을 발견하였다. 또한 1998-2008년 사이 능력과 자영업 진입과의 관계에 변화가 있었으며, 능력이 높은 사람이 대체로 자영업 성과도 좋다는 것을 확인하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2737-2742
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• 2003

Kinematic calibration enhances absolute accuracy by compensating for the fabrication tolerances and installation errors. Effectiveness of calibration procedures depends greatly on the measurements performed. While the Cartesian postures are measured completely, all of the geometric parameters can be identified to their true values. With partial pose measurements, however, few geometric parameters may not be identifiable and effectiveness of the calibration results may vary significantly within the workspace. QR decomposition of the identification Jacobian matrix can reveal the non-identifiable parameters. Selecting postures for measurement is also an important issue for efficient calibration procedure. Typically, the condition number of the identification Jacobian is minimized to find optimum postures. This paper investigates identifiable parameters and optimum postures for four different calibration procedures - measuring postures completely with inverse kinematic residuals, measuring postures completely with forward kinematics residuals, measuring only the three position components, and restraining the mobility of the end-effector using a constraint link. The study is performed for a six degree-of-freedom fully parallel HexaSlide type paralle manipulator, HSM. Results verify that all parameters are identifiable with complete posture measurements. For the case of position measurements, one and for the case of constraint link, three parameters were found non-identifiable. Optimal postures showed the same trend of orienting themselves on the boundaries of the search space.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.191-201
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• 2019

Macroecologists and biogeographers continue to predict the distribution of species across space based on the relationship between biotic processes and environmental variables. This approach uses data related to, for example, species abundance or presence/absence, climate, geomorphology, and soils. Researchers have acknowledged in their statistical analyses the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a degree of dependence between pairs of nearby observations. It has been agreed that residual spatial autocorrelation (rSAC) can have a substantial impact on modeling processes and inferences. However, more attention should be paid to the sources of rSAC and the degree to which rSAC becomes problematic. Here, we review previous studies to identify diverse factors that potentially induce the presence of rSAC in macroecological and biogeographical models. Furthermore, an emphasis is put on the quantification of rSAC by seeking to unveil the magnitude to which the presence of SAC in model residuals becomes detrimental to the modeling process. It turned out that five categories of factors can drive the presence of SAC in model residuals: ecological data and processes, scale and distance, missing variables, sampling design, and assumptions and methodological approaches. Additionally, we noted that more explicit and elaborated discussion of rSAC should be presented in species distribution modeling. Future investigations involving the quantification of rSAC are recommended in order to understand when rSAC can have an adverse effect on the modeling process.

• 한국물환경학회지
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• 제28권1호
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• pp.109-114
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• 2012

In this study, both sedimentation and thickening experiments were conducted for residuals produced from an advanced water treatment plant for more accurate and practical design of residual treatment train. In order to design a backwashed residual sedimentation basin (SRSB) in the filter backwash water recycle system, two kinds of backwash waters, one from sand filter (SFBW) and the other from GAC adsorption bed (GACBW), were separately collected and their surface loading rate measured. In addition, in order to design a gravity thickener, batch thickening tests were conducted for concentrated residuals taken from sedimentation basin and their limiting solid flux ($SF_{L}$) measured. From the experimental results and consideration of the seasonal characteristics of the residual, surface loading rate of $70m^{3}/m^{2}{\cdot}d$ was proposed as a design parameter for SRSB and solid loading rate of 20 kg $TS/m^{2}{\cdot}d$ was proposed as a design parameter for gravity thickeners. Finally, the material mass-balance was made for the design of each unit process in the residual treatment train.

• 대한토목학회논문집
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• 제10권4호
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• pp.53-66
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• 1990

산악의 영향을 받는 지역에서 비정상성 평균을 사용하는 G.C.모델에 의하여 총강우량의 우량곡면을 구성하였다. 구성된 우량곡면에 2차원 프리에 해석을 실시하여 강우의 주기성분을 분리하였다. 강우의 지엽성분, 즉 강우잔차는 우량곡면에서 주기성분을 제거하여 얻은 강우잔차를 균일한 무작위장의 표본함수라고 가정해서 이 무작위장의 특성을 자기상관함수로 나타냈다. 자기상관함수를 변환하여 스팩트럼 밀도를 구했고, 이 결과를 토대로 한강, 금강유역의 환상스팩트럼 분포함수의 모델을 제안했다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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• pp.75-75
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• 2003

All published and newly observed times of minimum light of the massive, early-type eclipsing binary star AH Cep were analyzed. After subtracting the light time effect due to the well-known third body from the residuals of the observed times of minimum light, it was found that the second-order Ο-C residuals varied in a cyclical way. It was assumed that the secondary oscillations were produced by a light time effect due to a fourth body so all the times of minimum light were reanalyzed with a differential least-squares scheme in order to obtain the light time orbits due to both the third and fourth bodies. The periods, eccentricities, semi-amplitudes of the light time orbits for the third and fourth-bodies were derived as : P$\_$3/=68.$\^$y/3 and P$\_$4/=9.$\^$y/3, e$_3$=0.53 and e$_4$=0.83, K$_3$=0.$\^$d/0585 and K$_4$=0.$\^$d/0045, respectively. The analysis of the radial velocities of AH Cep published so far, do not conflict with the hypothesis of the multiplicity of the system but their accuracies are not high enough to be useful to support the interpretation. Other properties of the distant bodies are discussed for assorted possible inclinations of their orbits.

• Journal of Astronomy and Space Sciences
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• 제16권1호
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• pp.21-30
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• 1999

소백산 천문대에서 1997년 2월부터 1998년 3월까지 총 3일 밤 동안 VRI 필터를 가지고 AK Her에 대한 CCD 측광관측을 수행하여 얻은 관측점의 수는 V는 236점, R은 198점, I는 197점이다. 관측 기간 동안 주극심과 부극심 시각을 각각 1개씩 관측하였으며, 우리의 관측자료를 가지고 VRI 광도곡선과 (O-C)도를 만들었다. Wilson-Devinney 방법으로 우리의 광도곡선을 분석한 결과 AK Her는 접촉형 (모드 3)의 경우는 해를 구할 수 없었고, 나머지(모드2, 4, 5)에 대해서는 접촉형에 가까운 분리형 또는 반분리형이라고 할 수 있었다. 우리의 최근자료를 가지고 만든 (O-C)도에서 AK Her 공전주기는 Borkovits & Hegedus의 예상과는 다르게 1990년도 이후 증가하는 변화가 나타났다.

• Nuclear Engineering and Technology
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• 제33권3호
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• pp.283-297
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• 2001

The CHF in PWR rod bundles is usually predicted by the local flow correlation approach based on subchannel analysis while difficulty exists due to the existence of spacer grids especially with mixing vanes. In order to evaluate the effect of spacer grids on CHF, the experimental rod bundle data with various types of spacer grids were analyzed using the subchannel code, COBRA-IV-i. For the Plain grid data, a CHF correlation was described as a function of local flow conditions and heated length, and then the residuals of the CHF in mixing vaned grids predicted by the correlation were examined in various kinds of grids. In order to compensate for the residual, three parameters, distances between grids and from the last grids to the CHF site, and equivalent hydraulic diameter were introduced into a grid parameter function representing the remaining effect of spacer grids predicted most of the CHF data points in plaing grids within $\pm$20 percent error band. Good agreement with the CHF data was also shown when the grid parameter function for mixing vaned grids of a specific design was used to compensate for the residuals of the CHF data predicted by the correlation.