• Clean Technology
• /
• v.18 no.1
• /
• pp.31-37
• /
• 2012

Biomass has become a major feedstock for bioenergy and other bio-based products because of its renewability and environmental benefits. Various researches have been done in the prediction of crucial characteristics of biomass, including the active utilization of spectroscopy data. Near infrared (NIR) spectroscopy has been widely used because of its attractive features: it's non-destructive and cost-effective producing fast and reliable analysis results. This work developed the multivariate statistical scheme for predicting weight loss profiles based on the utilization of NIR spectra data measured for six lignocellulosic biomass types. Wavelet analysis was used as a compression tool to suppress irrelevant noise and to select features or wavelengths that better explain NIR data. The developed scheme was demonstrated using real NIR data sets, in which different prediction models were evaluated in terms of prediction performance. In addition, the benefits of using right pretreatment of NIR spectra were also given. In our case, it turned out that compression of high-dimensional NIR spectra by wavelet and then PLS modeling yielded more reliable prediction results without handling full set of noisy data. This work showed that the developed scheme can be easily applied for rapid analysis of biomass.

• The Journal of the Korea Contents Association
• /
• v.7 no.10
• /
• pp.44-58
• /
• 2007

E-homestudy refers to e-Learning after school. This concept has been introduced by Korean Government as a substitute for expensive private tutoring. The purpose of this research is to explore the perceptions and relationships among determinants affecting the attitude and satisfaction level in e-homestudy. Such factors as subjective norms, visibility, perceived usefulness, quality of contents, facilitating conditions, interactions are introduced into the model. The survey results show that the attitude and the self-directed teaming level influence the satisfaction level in e-homestudy; the subjective norms, visibility, and perceived usefulness are the major determinant affecting the attitude; the quality of contents as well as interactions have positive impact on the perceived usefulness.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.35 no.1
• /
• pp.1-11
• /
• 2015

In this study, an online seed potato sorting system using a visible and near infrared (40 1100 nm) transmittance spectral technique and statistical model was evaluated for the nondestructive determination of infected and sound seed potatoes. Seed potatoes that had been artificially infected with Pectobacterium atrosepticum, which is known to cause a soil borne disease infection, were prepared for the experiments. After acquiring transmittance spectra from sound and infected seed potatoes, a determination algorithm for detecting infected seed potatoes was developed using the partial least square discriminant analysis method. The coefficient of determination($R^2_p$) of the prediction model was 0.943, and the classification accuracy was above 99% (n = 80) for discriminating diseased seed potatoes from sound ones. This online sorting system has good potential for developing a technique to detect agricultural products that are infected and contaminated by pathogens.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.1375-1376
• /
• 2015

본 논문은 퍼지 클러스터링을 이용한 규칙 성장 기반 퍼지 분류기의 설계에 대해서 소개한다. 본 논문의 목적은 퍼지 클러스터링을 통해 형성된 증가된 퍼지 규칙을 이용한 새로운 설계 방법론을 개발하는 것이다. 제안된 분류기는 네개의 기능적인 부분으로 구성된다. 퍼지 규칙의 전반부는 퍼지 클러스터링 알고리즘을 이용해 구성된 멤버쉽 함수를 나타낸다. 후반부는 지역 모델을 구성한다. 지역 모델의 파라미터는 가중 최소 자승법에 의해 추정된다. 추론부에서는, 각 퍼지 규칙의 에러 측정후, 가장 높은 에러를 갖는 하나의 퍼지 규칙이 선택된다. 규칙성장 부분에서는, 네트워크의 강화를 위해 규칙의 성장 과정이 이루어지며, 선택된 규칙은 제안된 분류기에서 더 나은 성능을 위해 두 개 또는 세 개의 세분화된 퍼지 규칙으로 나누어진다. 이러한 새로운 규칙은 context 기반 Fuzzy C-Means 클러스터링에 의해서 형성된다. 제안된 규칙 기반 분류기의 효용성을 토론하며, 머신 러닝 데이터를 이용하여 실험을 수행하였다.

• Korean Journal of Crystallography
• /
• v.7 no.2
• /
• pp.126-132
• /
• 1996

Cholesteryl isopropyl carbonate(C31O3H52) is orthorhombic, space group P212121, a=6.266(4), b=10.836(5), c=47.364(20)Å, Z=4, Dc=0.98 g/cm3 and Dm=1.01 g/cm3. The intensity data were collected on a Nonius CAD-4 diffractometer with a graphite-monochromatized MoKα radiation to a maximum 2θ value of 40°. The structure are solved by direct methods and refined by Fourier and full matrix least-squares methods. The present R factor was 0.22 for 1513 observed reflections. The further refinements are in progress. Compared with other cholesterol derivatives, the cholesteryl ring and tail region of the molecule are normal. The molecular long axes are parellel to the c-axis. There are close packings of cholesterol groups and loose packings of isopropyl carbonate chains forming monolayers.

• Journal of Environmental Science International
• /
• v.6 no.5
• /
• pp.541-550
• /
• 1997

A least-square regression analysis is applied for the estimation of velocity streamfunction field based on discretely sampled current meter data. The coefficients of a streamfuunction that is expanded in terms of trigonometric basis function are obtained by enforcing the horizontal non-divergence of two-dimensional flow field. This method avoids Interpolation and gives a root-mean-square (rms) residual of fit which Includes the divergent part and noisiness of oceanic data. The Implementation of the method Is done by employing a boundary-fitted, curvilinear orthogonal coordinate which facilitates the specification of boundary conditions. An application is successfully made to the Texas-Louisiana shelf using the 32 months current meter data (31 moorings) observed as a part of the Texas-Louisiana Shelf and Transport Processes Study (LATEX). The rms residual of the fitting is relatively small for the shelf, which indicates the field Is Ivell represented by the streamnfunction.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.3
• /
• pp.792-801
• /
• 1997

In this paper we propose an algorithm which fits a surface to noise-corrupted data points using an aceive sur-vace with global deformations.It is 3-dimensional surface extension of our precious works on 2-dimensional curve modell[11,12].We use fimite differences,and represent shapes of surface as global transfromation suring evolution based on the ballon [odel[2,3]which allows partial inflation or deflation by using niegborhood'sextermal foreces on each node points.At first,we make local deformations based on the balloon [odel,and then the blobal transformation from the surface before deformations to the defomed surface is calcualted by the deterministic lest squre method,finally we apply the global transformation to the surface before deformations.In experiments we fit a surface(elliposid,B-spline)to noise-corrupted 3D data points using the active surface with affine deformations.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.15 no.2
• /
• pp.204-210
• /
• 2005

This paper presents online identification algorithm for TSK fuzzy model. The proposed algorithm identify structure of premise part by using distance, and obtain the parameters of the piecewise linear function consisting consequent part by using recursive least square. Only input space was considered in Most researches on structure identification, but input and output space is considered in the proposed algorithm. By doing so, outliers are excluded in clustering effectively. The existing other algorithm has disadvantage that it is sensitive to noise by using data itself as cluster centers. The proposed algorithm is non-sensitive to noise not by using data itself as cluster centers. Model can be obtained through one pass and it is not needed to memorize many data in the proposed algorithm.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.5
• /
• pp.602-608
• /
• 2011

In this study, a method of designing a neurointerface using neural network (NN) is proposed for controlling nonholonomic mobile robots. According to the concept of virtual master-slave robots, in particular, a partially stable inverse dynamic model of the master robot is acquired online through the NN by applying a feedback-error learning method, in which the feedback controller is assumed to be based on a PD compensator for such a nonholonomic robot. The NN for the online feedback-error learning can composed that the input layer consists of six units for the inputs $x_i$, i=1~6, the hidden layer consists of two hidden units for hidden outputs $o_j$, j=1~2, and the output layer consists of two units for the outputs ${\tau}_k$, k=1~2. A tracking control problem is demonstrated by some simulations for a nonholonomic mobile robot with two-independent driving wheels. The initial q value was set to [0, 5, ${\pi}$].

• Journal of Biomedical Engineering Research
• /
• v.22 no.6
• /
• pp.497-502
• /
• 2001

Influence of other blond components on measuring glucose concentration was analyzed B)food phantom containing five major components was made. The prediction model was developed based on the measurement of absorption spectra including the first overtone glucose band, i.e.. 1500 ∼ 1850 nm. The concentrations were Predicted using the Partial least squares regression. Factor analysis based on Design of Experiment was Performed to study the influence of other components in predicting glucose concentration. Triglyceride does not influence. Albumin and globulin haute minor effects. However, hemoglobin showed substantial response and the compensation of hemoglobin concentration appears to be required for the model of glucose measurement.