• Atmosphere
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• v.18 no.3
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• pp.199-206
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• 2008

This study employs a structural time series method in order to model and estimate stochastic trend of surface temperatures of the globe, Northern Hemisphere, and Northeast Asia ($20^{\circ}N{\sim}60^{\circ}N$, $100^{\circ}E{\sim}150^{\circ}E$). For this study the reanalysis data CRUTEM3 (CRU/Hadley Centre gridded land-surface air temperature Version 3) is used. The results show that in these three regions range from $0.268^{\circ}C$ to $0.336^{\circ}C$ in 1997, whereas these vary from $0.423^{\circ}C$ to $0.583^{\circ}C$ in 2007. The annual mean temperature over Northeast Asia has increased by $0.031^{\circ}C$ in 2007 compared to 1997. The climate change in surface temperatures over Northeast Asia is slightly higher than that over the Northern Hemisphere.

• Proceedings of the KOSOMBE Conference
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• v.1990 no.11
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• pp.25-28
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• 1990

We tested the ability of two-dimensional echocardiograms of complete heart cycle in closed-chest human to discriminate between normal and infarcted myocardium using fixed window, Inter- and Intra-frame analysis. The results show that statistical parameter, MEAN, second order gray level statistics parameter, ASM and proposed parameter, HGE, I.T, can quantitatively distinguish between normal and Infarcted regions. The manner in which these parameters vary over the cardiac cycle is also a good indicator of the state of myocardium. The infarcted areas yield regions of higher Intensity throughout the cardiac cycle. Whereas, normal tissue demonstrates greater variability throughout the cardiac cycle.

• The Journal of Information Systems
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• v.10 no.1
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• pp.197-215
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• 2001

It is important to investigate into the critical success factors of the CIO system in order to formulate a successful introduction strategy of the system. In an effort to provide the background of the strategy, this research attempts to identify the characteristics of CIO's environment in Korea, such as the CEO, the colleagues, and the demographic statistics of the firm the CIO works for. A result from the analysis of data collected shows that about half the firms who responded to the survey have already adopted the CIO system. This implies that the value of the system is well recognized in Korea, considering that many of another half the firms are planning to adopt the system. Another result suggests that the bigger a firm is, the more the firm tends to adopt the CIO system and the higher the rank of CIO's colleagues is.

• Journal of Families and Better Life
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• v.28 no.2
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• pp.17-26
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• 2010

This study aimed to explore psychological separation from parents, family adaptability, and child's adjustment to college, in order to assess general standards and sex difference. It also investigated explaining variables on children's adjustment to college. The study subjects were 243 college students(male students; 123, female students; 120).The data collected from questionnaire were analyzed by descriptive statistics, t test, Pearson's correlation and hierarchical multiple regression. The main results were as follows: Firstly, psychological separation from parents of college students were lower than those of average score. But family adaptability and adjustment to college of students were higher than those of average score. Secondly, psychological separation from parents was negatively correlated to adjustment to college, but family adaptability was positively correlated to adjustment to college. Finally, variables that explain child's adjustment to college was cohavitation with parents and family adaptability. In addition to these variables, psychological separation from parents was a major factor for female students.

• Fashion & Textile Research Journal
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• v.10 no.1
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• pp.40-49
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• 2008

The purposes of this study were to investigate the effects of market orientation and learning orientation of textile firms on business performance and to confirm the moderating effect of company innovativeness on these relationships. Data collected from 167 textile firms through survey were analyzed by descriptive statistics, t-tests, and multiple causal modeling using AMOS 6.0. In results, the higher innovativeness, the stronger effect of market orientation on business performance. Also, the lower innovativeness, the stronger effect of learning orientation on business performance. Study results may suggest the needs of different focus of organization culture according to company characteristics in order to improve business performance.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1801-1805
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• 2003

The intermittent characteristics of fluid particle accelerations near the wall are investigated with the higher-order statistics and the probability density functions (PDF) by using a direct numerical simulation of turbulent channel flow. Also, the behaviors of acceleration associated with the coherent structures are discussed. The flatness factor of wall-normal acceleration is extremely high near the wall and it exceeds the previously reported value obtained in isotropic turbulence. The presence of the wall seems to make the accelerations more intermittent and the associated mechanism is explained with the PDFs. The skewness factor of wall-normal acceleration indicates that accelerations are associated with the streamwise vortices.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.881-888
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• 2008

We present a novel fault diagnosis methodology using acoustic sensor systems and neural independent component analysis for large-scaled power machines. Acoustic sensors are carried out to measure sounds generated from power machines whose signal is used to determine whether fault is occurred or not. Acoustic measurements are independently mixed and deteriorated from original source signals. We propose a demixing algorithm against such mixed signals by means of independent component analysis which is achieved based on information theory and higher-order statistics to derive learning mechanism.

• Proceedings of the Acoustical Society of Korea Conference
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• 1995.06a
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• pp.55-60
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• 1995

고차 통계 방법을 이용하여 잡음이 섞인 음성 신호에서 피치를 구하는 방법과 이를 이용하여 유성음 및 무성음 구간을 구분하는 방법을 구현하고 그 결과를 기술하였다. 고차 통계의 일종인 3차 cumulant 함수의 경우 Gaussian 또는 대칭적인 분포를 갖는 잡음 신호를 음성신호로부터 효과적으로 분리하여 제거시키는 특징을 가지고 있으며, 이러한 특징을 이용하면 잡음 환경에서 여러 가지 음성 특징 파라메터들을 보다 신뢰도 높게 추정할 수 있다. 본 논문에서는 dam성 신호의 3차 cumulant 함수의 자기상관함수로부터 음성의 피치 주기를 추정하였으며, 피치 위치에서의 normalized peak 크기에 의해 유성음과 무성음을 구분하였다. 또한 성능 비교를 위해 음성 신호 자체의 자기 상관 함수로부터 역시 피치 주기 및 유성음/무성음 구분을 수행하였다. 백색 및 유색 Gaussian 잡음 환경에서의 음성의 피치 주기 추정 실험 결과 SNR가 낮은 경우에 3차 cumulant를 이용한 방법이 2차 통계에 비해 우수한 성능을 나타내었다. 또한 동일한 잡음 환경에서의 유성음/무성음 판별 시험에서도 3차 cumulant를 이용한 방법이 기존의 2차 통계를 이용한 방법에 비해 성능이 크게 향상된 결과를 얻었다.

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

• Communications for Statistical Applications and Methods
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• v.16 no.6
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• pp.1031-1036
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• 2009

Under recent dramatic declines in response rates, various procedures have been considered among survey practitioners to reduce nonresponse in order to avoid its potential impairment to the inference. In the random digit dialing telephone surveys, substantial efforts are often required to obtain the initial contact for the screener interview. To reduce a burden with higher data collection costs, refusal conversion can be administered only to a random portion of the sample, reducing nonresponse (bias) with an expense of sample variability increment due to the associated weight adjustment. In this paper, we provide ways to determine the optimal subsampling rate using a linear cost model. Our approach for refusal subsampling is to predetermine a random portion from the full sample and to apply refusal conversion efforts if needed only to the subsample.