• Journal of Institute of Control, Robotics and Systems
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• v.6 no.3
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• pp.273-283
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• 2000

In this paper we suggest an optimal design method of Fuzzy-Neural Networks(FNN) model for complex and nonlinear systems. The FNNs use the simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rule. And we use a HCM(Hard C-Means) Clustering Algorithm to find initial parameters of the membership function. The parameters such as parameters of membership functions learning rates and momentum weighted value is proposed to achieve a sound balance between approximation and generalization abilities of the model. According to selection and adjustment of a weighting factor of an aggregate objective function which depends on the number of data and a certain degree of nonlinearity (distribution of I/O data we show that it is available and effective to design and optimal FNN model structure with a mutual balance and dependency between approximation and generalization abilities. This methodology sheds light on the role and impact of different parameters of the model on its performance (especially the mapping and predicting capabilities of the rule based computing). To evaluate the performance of the proposed model we use the time series data for gas furnace the data of sewage treatment process and traffic route choice process.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.26 no.2
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• pp.99-103
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• 2020

The volume of parcel delivery is steadily increasing with the rapid growth of the global online e-commerce market. However, a large amount of packaging materials used for these parcel delivery is finally causing environmental problems as waste. In this study, we have taken a pilot test on the returnable parcel delivery packaging & service, which is one of various ways to reduce the generation of the distribution packaging waste raised by e-commerce-based parcel delivery. For the purpose of this project, we made 300 boxes of returnable & foldable delivery packaging(415 mm × 280 mm × 160 mm) and have cooperated with e-commerce company(CJ ENM) & logistics company(LogisAll). Consequently, about 50% of the delivered packages was returned because of the lack of consumer's understanding on the returnable packaging system. We finally have suggested the policy strategy to get over problems derived from the experiment, like the retrieval rate and cost of the returnable packaging, economic efficiency and so on.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.327-336
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• 2010

The purpose of this study was to analyze muscle activities on functional insole with diet effect. Originally, ten healthy female subjects with an average age of 23.2 year(S.D=1.1), weight of 49.7 kg(S.D=4.9), height of 163.2 cm(S.D=3.5) and a shoe size of 237.5 cm(S.D=4.9) were participated in this experiment. Ten healthy females walked on a treadmill(speed=about 4.2 km/h) wearing two different insole types. Muscle activities data was collected using the EMG operating system. The surface EMG signal for tibialis anterior(TA), gastrocnemius(GA), vatus lateralis(VL) and biceps femoris(BF) were acquired at the RMS(10 Hz, 350 Hz) using Noraxon Telemyo DTS system(Noraxon inc, USA). This study processed the data using the Windows SPSS ver.17.0 to get an independent t-test, with the setting, p<.05. Analysis of muscle activity were measured and calculated during walking. The results are as follow: Functional insole wearing were increased muscle activities significantly from Tibialis anterior(TA) during total gait cycle. Normal distribution was demonstrated in total step of stances period. One foot standing position showed decreased muscle activity. Two foot standing position was demonstrated with gastrocnemius and biceps femoris. As a result of the analysis, Functional insole will inerease the diet effect in the use of four muscle groups.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.2
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• pp.1-6
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• 2008

A compact analytical model of the threshold voltage for long-channel Asymmetric Double-Gate(ADG) MOSFET is presented. In contrast to the previous models, channel doping and carrier quantization are taken into account. A more compact model is derived by utilizing the potential distribution linearity characteristic of silicon film at threshold. The accuracy of the model is verified by comparisons with numerical simulations for various silicon film thickness, channel doping concentration and oxide thickness.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.220-222
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• 2005

We can classify two cases in a way to observe an atom of gas state or a molecule using the laser. First case is way to use dispersion phenomenon like Rayleigh scattering, Thomson scattering, Mie scattering, Raman Scattering. And Second case is a way to use change phenomenon like a LAS (Laser Absorption Spectroscopy), LIF (Laser Induced Fluorescent). In this paper, we have measured the meta-stable density and the distribution by using a LAS method in Xe discharge lamp. The laser absorption spectroscopy (LAS) is useful to investigate the behavior of such species. The xenon atoms in the $1S_4$ and $1S_5$ generate excited $Xe^*$(147nm) and $Xe_{2}^*$(173nm) dimers in Xe plasma. It is found that the intensity of VUV 147nm emission is proportional to that of the IR 828nm emission, and the VUV 173nm emission is roughly proportional to that of the IR 823nm emission. The laser is used CW laser that consist of AlGaAs semiconductor and energy level is used 823.16nm wavelength. We measured signal of monochrometer from the lamp center while will change a discharge electric current by 6mA in 3mA and calculated meta-stable state density of a xenon atom through a measured value.

• Journal of the Korean Home Economics Association
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• v.44 no.1 s.215
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• pp.1-10
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• 2006

The purpose of this study was to develop a scale to access a creative home environment for preschool children and to examine its validity and reliability. The subjects were 296 children aged 5 to 6 years(148 males and 148 females) and their parents. The methods for data analysis included item analysis, factor analysis for construct validity, Pearson correlations between the rating scale for creative characteristics of preschoolers(RSCCP) and this scale for concurrent validity, and Cronbach's ${\alpha}$ for reliability. The 44 items of the scale were found be satisfactory in terms of item response distribution and item discrimination. Four factors were extracted from the factor analysis: the subscales labelled 'respect for the child', 'enriched learning environment', 'stimulation of independence' and 'family pressure'. The concurrent validity of this scale was accessed by computing the correlation measures of RSCCP with this scale. Most coefficients were significant. Cronbach's ${\alpha}$ ranged from.75 to.86 for the 4 subscales and.85 for the total scale.

• Transactions on Electrical and Electronic Materials
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• v.11 no.2
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• pp.54-60
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• 2010

Polymer-assisted deposition is a chemical solution route to high quality thin films. In this process, the polymer controls the viscosity and binds metal ions, resulting in a homogeneous distribution of metal precursors in the solution and the formation of crack-free and uniform films after thermal treatment. We review our recent effort to epitaxially grow metal-nitride thin films, such as hexagonal GaN, cubic TiN, AlN, NbN, and VN, mixed-nitride $Ti_{1-x}Al_xN$, ternary nitrides tetragonal $SrTiN_2$, $BaZrN_2$, and $BaHfN_2$, hexagonal $FeMoN_2$, and nanocomposite TiN-$BaZrN_2$.

• Smart Structures and Systems
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• v.5 no.3
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• pp.241-260
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• 2009

Shape control of flexible structures using piezoelectric materials has attracted much attention due to its wide applications in controllable systems such as space and aeronautical engineering. The major work in the field is to find a best control voltage or an optimal placement of the piezoelectric actuators in order to actuate the structure shape as close as possible to the desired one. The current research focus on the investigation of static shape control of intelligent shells using spatially distributed piezoelectric curve beam actuators. The finite element formulation of the piezoelectric model is briefly described. The piezoelectric curve beam element is then integrated into a collocated host shell element by using nodal displacement constraint equations. The linear least square method (LLSM) is employed to get the optimum voltage distributions in the control system so that the desired structure shape can be well matched. Furthermore, to find the optimal placement of the piezoelectric curve beam actuators, a genetic algorithm (GA) is introduced in the computation model as well as the consideration of the different objective functions. Numerical results are given to demonstrate the validity of the theoretical model and numerical algorithm developed.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.281-288
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• 2014

A method for edge detection using K-means clustering is proposed in this paper. The method is performed through there steps. Histogram equalizing is applied to the image for the uniformed intensity distribution. Pixels are clustered by K-means clustering technique. Then Sobel mask is applied to detect edges. Experiments showed that this method detected edges better than conventional method.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.268-268
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• 2011

GaAs (001) 기판에 MBE를 이용하여 자발형성법으로 성장한 InAs 양자점(QDs: quantum dots)의 광학적 특성을 PL (photoluminescence)과 TRPL (time-resolved PL)을 이용하여 분석하였다. InAs 양자점 성장 동안 In 공급은 계속하면서 As 공급을 주기적으로 차단과 공급을 반복하면서 성장하였다. As 차단과 공급을 1초, 2초, 그리고 3초씩 하면서 InAs 양자점을 성장하였다. 기준시료는 In과 As 공급을 중단하지 않고 20초 동안 성장하였다. As interruption mode로 성장한 시료들의 QD density는 기준시료에 비해 증가하였으며, size distribution도 기준시료에 비해 향상되었다. 기준시료와 비교하였을 때, As interruption mode로 성장한 시료들의 PL 피크는 적색이동 (red-shift)를 보였으며, PL 세기는 2배 이상 증가하였다. PL 소멸곡선은 파장이 증가함에 따라 점차 느려지다가 PL 피크에서 가장 느린 소멸을 보인 후 다시 점차 빠르게 소멸하였다. 시료의 온도를 10 K에서 60 K까지 증가하였을 때 PL 피크 에너지는 변하지 않았으며, PL 소멸시간은 서서히 증가함을 보였다. 온도를 더 증가하였을 때 PL 피크 에너지는 적색이동 하였으며 PL 소멸시간도 빠르게 감소함을 보였다. As interruption mode로 성장한 양자점 시료의 구조적 특성 변화에 의한 광학적 특성 변화를 확인하였다.