• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.537-542
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• 2007

This paper proposes a 2-step Kalman filter model for land vehicle navigation using civilian-band GPS measurements. The velocity bias caused by the Earth#s rotation would be removed completely when applying this model. Because the linearization of velocity equations in this model is not necessary, the error is significantly reduced. The experiment reveals that estimated position error with stationary data is about 5m during a 15-20 minute interval. The other benefit of this model is that it can be feasibly applied as a GPS receiver module thanks to the small sizes of the necessary manipulating matrices.

• Journal of Navigation and Port Research
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• v.28 no.9
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• pp.803-808
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• 2004

In this paper, an INS compensation algorithm is proposed using the accelerometer from IMU. First, we denote the basic INS algorithm and show that how to compensate the position error when low cost IMU is used. Second, considering the ship's characteristic and ocean environments, we consider with a drift as a periodic external environment change which is affected with exact position. To develop the compensation algorithm, we use a repetitive method to reduce the external environment changes. Lastly, we verify the proposed algorithm through the experiments, where the acceleration sensor is used to acquire real data.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.278-282
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• 2004

The Hydrogenated amorphous carbon(a-C:H) thin films are deposited on silicon with a close field unbalanced magnetron(CFUBM) sputtering systems. The experimental data are obtained on the depositon rate and physical properties of a-C:H films using DC bias voltage and Ar/C$_2$H$_2$ pressure. The depostion rate and the surface roughness decrease with DC bias voltage, but the hardness of the thin films increases with DC bias voltage. And the position of G-peak moves to lower wavenumber indicating an increase in diamond-like carbon characteristics with the lower Ar/C$_2$H$_2$ pressure.

• Transactions on Electrical and Electronic Materials
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• v.17 no.2
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• pp.113-117
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• 2016

Temperature dependent reverse-bias current-voltage (I-V) characteristics in Cu Schottky contacts to oxygen plasma treated n-InP were investigated. For untreated sample, current transport mechanisms at low and high temperatures were explained by thermionic emission (TE) and TE combined with barrier lowering, respectively. For plasma treated sample, experimental I-V data were explained by TE or TE combined with barrier lowering models at low and high temperatures. However, the current transport was explained by a thermionic field emission (TFE) model at intermediate temperatures. From X-ray photoemission spectroscopy (XPS) measurements, phosphorus vacancies (VP) were suggested to be generated after oxygen plasma treatment. V_P possibly involves defects contributing to the current transport at intermediate temperatures. Therefore, minimizing the generation of these defects after oxygen plasma treatment is required to reduce the reverse-bias leakage current.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.45-53
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• 2004

In this paper, an INS compensation algorithm for auto sailing system is proposed, where low cost IMU (Inertial Measurement Unit) is used for measuring the accelerometer data. First, we denote the basic INS algorithm with IMU and show that how to compensate the error of position by using low cost IMU. Second, in considering the ship's characteristic and ocean environments, we consider with a factor as a periodic external disturbance which effects to the exact position. To develop the compensation algorithm, we use a repetitive method to reduce the external environment changes. Lastly, we verify the proposed algorithm by using experiments results.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.5
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• pp.485-489
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• 2015

An accurate large-signal BSIM4 macro model including new empirical bias-dependent equations of the drain-source capacitance and channel resistance constructed from bias-dependent data extracted from S-parameters of RF MOSFETs is developed to reduce $S_{22}$-parameter error of a conventional BSIM4 model. Its accuracy is validated by finding the much better agreement up to 40 GHz between the measured and modeled $S_{22}$-parameter than the conventional one in the wide bias range.

• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.373-381
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• 2009

Evidence of linkage is expressed as a decreasing trend of the squared trait difference of two siblings with increasing identical by descent scores. In contrast to successes in the application of a parametric approach of Haseman-Elston regression, notably low powers are demonstrated in the nonparametric linkage analysis methods for complex traits and diseases with sib-pairs data. We report that the Genehunter nonparametric linkage statistic is biased and furthermore the variance formula that they used is an inflated one, and this is one reason for a low performance. Thus, we propose bias-corrected nonparametric linkage statistics. Simulation studies comparing our proposed nonparametric test statistics versus the existing test statistics suggest that the bias-corrected new nonparametric test statistics are more powerful and attains efficiencies close to that of Haseman-Elston regression.

• Journal of Distribution Science
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• v.12 no.9
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• pp.83-93
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• 2014

Purpose - This study attempted to identify any influencing relationships, between the antecedent variables and the members' innovative work behavior, which were expected to influence organizational performance based on the extended theory of planned behavior (ETPB). Research design, data, and methodology - The survey was conducted on SMEs in Seoul and its metropolitan area. A total of 158 copies of effective questionnaires were used and were analyzed through correlation analysis, regression analysis, and multiple regression. Results - Self-efficacy, value, intrinsic motivation, and self-enhancing bias have been found to have a positive relationship with innovative work behavior. In addition, transformational leadership was found to moderate the existence of a statistically significant negative influence between value, intrinsic motivation, and innovative work behavior. Conclusions - The results suggest that leaders will be successful in winning members' trust through conducting their behaviors in accordance with the applicable ethical and moral standards and through their fair, transparent, and legitimate management practices with an attitude of 'taking the initiative and setting an example', and this will help solve such problems.

• Phonetics and Speech Sciences
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• v.4 no.1
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• pp.55-65
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• 2012

In this study, the prosodic disambiguation of the syntactic attachment differences was investigated in relation to the effect of lexical bias. Speech materials were composed of N1-conj-N2-PP phrases such as "walkers and runners with dogs." The results show that the use of durational pattern is dominant over the pitch pattern to differentiate the attachment differences. The characteristic pitch contour was the rise and fall over N1 and N2 in the high attachment. The pitch contour in the low attachment was the rise and fall over N2 and N3 although the frequency of such patterns was lower for the low attachment case. For the durational pattern, the lengthening in the N2 region plays a significant role in the disambiguation of the syntactic attachments. The interaction between the lexical bias and the syntactic attachment was not statistically significant in the duration data.

• Journal of the Korean Statistical Society
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• v.31 no.1
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• pp.63-75
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• 2002

Most attempts at Bayesian analysis of neural networks involve hierarchical modeling. We believe that similar results can be obtained with simpler models that require less computational effort, as long as appropriate restrictions are placed on parameters in order to ensure propriety of posterior distributions. In particular, we adopt a model first introduced by Lee (1999) that utilizes an improper prior for all parameters. Straightforward Gibbs sampling is possible, with the exception of the bias parameters, which are embedded in nonlinear sigmoidal functions. In addition to the problems posed by nonlinearity, direct sampling from the posterior distributions of the bias parameters is compounded due to the duplication of hidden nodes, which is a source of multimodality. In this regard, we focus on sampling from the marginal posterior distribution of the bias parameters with Markov chain Monte Carlo methods that combine traditional Metropolis sampling with a slice sampler described by Neal (1997, 2001). The methods are illustrated with data examples that are largely confined to the analysis of nonparametric regression models.