• Journal for History of Mathematics
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• v.11 no.2
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• pp.63-76
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• 1998

When teaching the linear regression analysis in the class, the power transformation must be introduced to fit the linear regression model for nonlinear data. Box and Cox (1964) proposed the attractive power transformation technique which is so called Box-Cox transformation. In this paper, an effective algorithm selecting an appropriate value for Box-Cox transformation is developed which is considered to find a value minimizing error sum of squares. When the proposed algorithm is used to find a value for transformation, the number of iterations needs to be considered. Thus, the number of iterations is examined through simulation study. Since SAS is one of most widely used packages and does not provide the procedure that performs iterative Box-Cox transformation, a SAS program automatically choosing the value for transformation is developed. Hence, the students could learn how the Box-Cox transformation works, moreover, researchers can use this for analysis of data.

• The Korean Journal of Food And Nutrition
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• v.7 no.3
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• pp.213-218
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• 1994

본 연구는 식품의 물성을 측정하기 위한 한 가지 방법으로 50 변위를 아주 정밀하게 직선적으로 측정이 가능한 linear proximity sensor(선형 근접 센서)를 활용하여 식빵의 굳기를 측정하였다 선형 근접 센서를 장착한 기구로 몇 가지 응력(0.376, 0.543, 0.769 kPa) 하에서 식빵의 온도와 수분 함량에 따른 변형을 컴퓨터 자동 자료 수집 장치를 통하여 on-line 상태로 매초마다 자료를 수집하여 컴퓨터 자료 분석 program으로 그래프를 얻었다. 식빵에 적용한 응력과 strain의 비율은 응력이 클수록 그 값이 커지는 비 선형 점 탄성체의 성질을 보였다. 이 측정 기구는 좁은 온도범위와 작은 수분함량의 차이에 따른 식빵의 굳기의 정도에 현저한 차이가 있음을 관찰할 수 있었다. 선형 근접 센서를 활용한 이 기구는 간단하면서도 정밀하게 동적으로 식품의 물성을 측정할 수 있었고, 높은 반복성을 나타내었다. 또한 수집된 자료는 점 탄성체의 특성을 설명하는 기계적인 모형으로 나타낼 수 있었다. Inokuchi의 방법을 적용하여 식빵의 물성을 모형화 하면 용수철과 완충 장치의 조합으로 나타내는 Burger's 모형에 잘 일치하였다. 본 측정 장치는 설치와 사용이 간단하여 식빵과 같은 연 식품의 물성을 측정하는데 활용이 용이하였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.5 no.2
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• pp.47-55
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• 1987

In this paper, the direct linear transformation is described in which a inner and exterior orientation parameters are treated as unknown for non-iterative direct space resection, and the computer program was developed to obtain object space coordinates. Image coordinates measurements are conducted with analogue stereo-plotter and digitizer. To prove the appropriateness of the two image coordinate measurement devices and the DLT method, the standard errors of object space coordinates are compared with semi-analytical method.

• Journal of the Korea Society of Computer and Information
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• v.22 no.7
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• pp.31-37
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• 2017

There are lots of combined battlefield elements which complete the war. It looks problematic when collecting and analyzing these elements and then predicting the situation of war. Commander's experience and military power assessment have widely been used to come up with these problems, then simulated combat training program recently supplements the war-game models through recording real-time simulated combat data. Nevertheless, there are challenges to assess winning factors of combat. In this paper, we characterize the combat element (ce) by clustering simulated combat data, and then suggest multi-layered artificial neural network (ANN) model, which can comprehend non-linear, cross-connected effects among ces to assess mission completion degree (MCD). Through our ANN model, we have the chance of analyzing and predicting winning factors. Experimental results show that our ANN model can explain MCDs through networking ces which overperform multiple linear regression model. Moreover, sensitivity analysis of ces will be the basis of predicting combat situation.

• Computational Structural Engineering
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• v.7 no.2
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• pp.61-67
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• 1994

The objective of this numerical analysis is to trace the hysteretic behavior of steel angles under very-low-cycle loading test, especially the history and cumulative state of local stress-strain at their critical parts. The computer model is based on a three-dimensional, non-linear analysis by using the finite element program, MSC/NASTRAN, which includes the effects of the material and geometric non-linearities. The analysis was performed as two stage procedures, namely Analysis I and II. The overall behavior from this analysis showed good agreement with the experiment.

• Proceedings of the KSR Conference
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• 1998.05a
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• pp.540-547
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• 1998

light rail vehicle is modeled as a 2 d. o. f linear system for the design of vertical suspension characteristics and a 4 d. o. f. linear system for the design of lateral suspension characteristics. FRA's class-5-track irregularity is used for the exciting disturbance on track. Suspension stiffness and damping is selected on the basis of the ride quality and suspension stroke trade-off for the bogie of light rail vehicle. The optimum value of primary and secondary suspension characteristics is determined. And the stability of full vehicle model for the LRV is analyzed using the VAMPIRE program and critical speed is determined.

• Proceedings of the KSR Conference
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• 1998.05a
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• pp.580-587
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• 1998

For many decades, the railway was constructed using tracks with jointed rails of relatively short lengths in accordance with rolling and handling technology. The joints cause many drawbacks in the track and lead to significant maintenance cost. So, railroad engineers became interested in eliminating joints to increase service loads and speeds by improving rolling, welding, and fastening technology, Continuous welded rail(CWR) track has many advantages over the conventional jointed-rail track. But in the case of the elimination of rail joints, it may cause the track to be suddenly buckled laterally by thermal and vehicle loads. Thermal loads are caused by an increase in the temperature of railway track. In this paper, CWR track model and CWRB program are developed for linear buckling analysis using finite element method(FEM). The finite element discretization is used with a total of 14 degrees of freedom for each rail element. The stiffness of the fastener, tie, and ballast bed are included by a set of spring elements. The investigation on the buckling modes and temperature of CWR track is presented in the paper.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.766-768
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• 2000

In this paper, we present the optial design and analysis of a novel brushless do linear motor, which can operate as a selfless linear stepping motor, with two armature cores and two back iron and five high energy product magnets. We used Maxwell program package for computing the flux distribution and static force. The assessment of the analytical and measured values shows a very goof correlation among them. The result are presented in this paper.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.209-213
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• 1998

In the paper, we present the design procedure and analysis the fundamental characteristics for Linear DC Motor(LDM) using permeance method and finite element method (FEM). Designed LDM is made of two permanent magnets, three iron core and armature windings. For the design of the LDM, first of all it is necessary to calculate the air gap flux density and thrust force, after that to determine core size, the numbers of winding turns, winding width, etc. To demonstrate the method of caculation yields the right results, we used Maxwell program package for computing magnetic fields. Finally we find that the proposed design procedure in this paper is effective to design of LDM.

• Steel and Composite Structures
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• v.8 no.4
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• pp.265-280
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• 2008

An investigation on the combined effect of foundation type, foundation flexibility, axial load and PR (semi-rigid) connections on the natural frequencies of steel frames is presented. These effects were investigated using a suitable modified FE program for cases where the foundation flexibility, foundation connectivity, and semi-rigid connections could be treated as equivalent linear springs. The effect of axial load on the natural frequency of a structure was found to be significant for slender structures subjected to high axial loads. In general, if columns of medium slenderness are designed without consideration of axial load effects, the frequency of the structure will be overestimated. Studies on the 3-story Los Angeles PR SAC frame indicate that the assumption of rigid connections at beam-column and column-base interfaces, as well as the assumption of a rigid foundation, can lead to significant errors if simplified design procedures are used. These errors in an equivalent static analysis are expected to lead to even more serious problems when considering the effect of higher modes under a non-linear dynamic analysis.