• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.3
• /
• pp.53-60
• /
• 2008

Recently, various recording technologies are studied for optical data storage. After standardization of BD (Blue-ray Disc) and HD-DVD (High-Definition Digital Versatile Disc), the industry is looking for a suitable technology for next generation optical data storage. Super-RENS (Super-resolution near field structure) technique, which is capable of compatibility with other systems, is one of next optical data storage. In this paper, we analyze the nonlinearity of Super-RENS read-out signal through the bicoherence test, which uses HOS (Higher-Order Statistics) and apply neural networks for nonlinear modeling. The model structure considered in this paper is the NARX (Nonlinear AutoRegressive eXogenous) model. The experiment results indicate that the read-out signals have nonlinear characteristics. In addition, it verified the possibility that neural networks can be utilized for nonlinear modeling of Super-RENS systems.

• Journal of the Korean Society of School Health
• /
• v.30 no.2
• /
• pp.174-180
• /
• 2017

Purpose: This study examined depression, ego-resilience and health behaviors of high school student in order to understand the relationship among these variables. Methods: The study used raw data from the Korean Children and Youth Panel Survey conducted in 2015. Data was analyzed using SPSS 21.0 for descriptive statistics, t-test, $x^2$ test, Pearson's correlation coefficients, and multiple regression analysis. Results: Gender, school performance, economic status, subjective health status, drinking behavior and ego-resilience had significant effects on depression. Moreover, school performance, subjective health status, smoking behavior, duration of exercise during physical education classes, and depression had significant effects on ego-resilience. Conclusion: Based on these findings, we need to develop the interventions for depression and ego-resilience for adolescents, considering the related factors to health status and behaviors.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.53 no.9
• /
• pp.663-669
• /
• 2004

The mobile tole-cardiology system is the new research area that support an ubiquitous health care based on mobile telecommunication networks. Although there are many researches presenting the modeling concepts of a GSM-based mobile telemedical system, practical application needs to be considered both compression performance and error corruption in the mobile environment. This paper evaluates three wavelet ECG compression algorithms over CDMA networks. The three selected methods are Rajoub using EPE thresholding, Embedded Zerotree Wavelet(EZW) and Wavelet transform Higher Order Statistics Coding(WHOSC) with linear prediction. All methodologies protected more significant information using Forward Error Correction coding and measured not only compression performance in noise-free but also error robustness and delay profile in CDMA environment. In addition, from the field test we analyzed the PRD for movement speed and the features of CDMA 1X. The test results show that Rajoub has low robustness over high error attack and EZW contributes to more efficient exploitation in variable bandwidth and high error. WHOSC has high robustness in overall BER but loses performance about particular abnormal ECG.

• The Korean Journal of Applied Statistics
• /
• v.31 no.4
• /
• pp.485-495
• /
• 2018

The CCC-r chart is more effective than traditional attribute control charts for monitoring high-quality processes. In-control process parameters are typically unknown and should be estimated when implementing a CCC-r chart. Phase II control chart performance can deteriorate due to the effect of the estimation error. In this paper, we used the standard deviation of average run length (ARL) as well as the average of ARL to quantify the between-practitioner variability in the CCC-r chart performance. The results indicate that the CCC-r chart requires larger Phase I data than previously recommended in the literature in order to have consistent chart in-control performance among practitioners.

• Journal for History of Mathematics
• /
• v.24 no.4
• /
• pp.119-141
• /
• 2011

This paper analysed the mathematical paradoxes which would be based in the probability and statistics. Teachers need to endeavor various data in order to lead student's interest. This paper says mathematical paradoxes in mathematics education makes student have interest and concern when they study mathematics. So, teachers will recognize the need and efficiency of class for using mathematical Paradoxes, students will be promoted to study mathematics by having interest and concern. These study can show the value of paradoxes in the concept of probability and statistics, and illuminate the concept being taught in classroom. Consequently, mathematical paradoxes in mathematics education can be used efficient studying tool.

• Spatial Information Research
• /
• v.23 no.3
• /
• pp.67-77
• /
• 2015

This Study aimed to construction the plan of the statistics for national greenhouse gas inventories of international standards. Currently, the statistics of the greenhouse gas inventories of South Korea, has a problem that is not able to build the changed information. In previous studies, it has been limited to the construction of the information within each category. In order to solve these problems, targeting Gyeonggi province, we analyzed the land use change by utilizing the various information such as satellite images, KLIS, UPIS. As a result, we suggested the following implementation, classification system of LULUCF category, improvement of accuracy by utilizing satellite images of high resolution, additional research for methodology. Based on these contents, we suggested the construction plan of the statistics for national greenhouse gas inventories(LULUCF sector). Frist, it is necessary to construct of land use change informations for the past 20 years, Then, it need to create the matrix of land use change by utilizing satellite images and various land information systems.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.6C
• /
• pp.629-636
• /
• 2006

In array signal processing, high order statistics can be used to estimate parameters from signal of sums of complex exponential. In this paper, we derive two types of direction finding algorithms which use the fourth-order cumulant and moment of the received array data. Since the fourth order cumulant can suppress the Gaussian noise, the response of MPM has better noise immunity than the conventional approaches. The performance of each method in regard to the probability of resolution and SNR in the presence of the Gaussian noise is investigated. As a result, the proposed method applied to the fourth-order statistic can find DOA more correctly in the presence of the Gaussian noise.

• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.2
• /
• pp.57.2-57.2
• /
• 2013

Cosmology is entering an era of percent precision with large surveys, demanding accurate simulations. In this paper, we aim to study the effects of initial conditions on the results of cosmological simulations, which will help us to make percent-level accuracy simulations. For this purpose, we use a series of cosmological N-body simulations with varying initial conditions. We test the influence of the initial conditions, namely the pre-initial configuration (preIC), the order of the perturbation theory, and the initial redshift, on the statistics associated with the large scale structures of the universe such as the halo mass function, the density power spectrum, and the maximal extent of the large scale structures. We find that glass or grid pre-initial conditions give similar results. However, the order of the Lagrangian perturbation theory used to generate the initial conditions and the starting epoch of the simulations play a crucial role, especially at high redshift (z ~ 2-4). The initial conditions have to be chosen with care, taking into account the specificity of the simulation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.5
• /
• pp.1274-1282
• /
• 1996

This paper deals with an inverse modeling of nonminimum phase communication channel utilizing the HOS (High Order Statistics) of the received signal. After the communication channel is separated into the minimum phase and maximum phase components, the inverse modeling is performed independently. The performance superiority is confirmed by monte-carlo computer simulation in comparison with the traditional CMA (Constant Modulus Algorithm) method. By utilizing the proposed algorithm employing the HOS of the received signal, the inverse frequency characteristics of the channel can be obtained withoug transmitted signal in digital communication. This algorithm is required in preprocessing or postprocessing in order to remove the channel effect, and effective in the self adaptive equalizer which can minimize the bit error rate or symbol error rate in the recovry of received signal.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.17 no.2
• /
• pp.67-85
• /
• 2013

Reproducing Polynomial Particle Method (RPPM) is one of meshless methods that use meshes minimally or do not use meshes at all. In this paper, the RPPM is employed for free vibration analysis of shear-deformable plates of the first order shear deformation model (FSDT), called Reissner-Mindlin plate. For numerical implementation, we use flat-top partition of unity functions, introduced by Oh et al, and patchwise RPPM in which approximation functions have high order polynomial reproducing property and the Kronecker delta property. Also, we demonstrate that our method is highly effective than other existing results for various aspect ratios and boundary conditions.