• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05a
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• pp.66-70
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• 2001

The partial discharge testing is widely used in diagnostic measuring technology because it gives low stress to power equipment which is undertaken tests. Therefore it is very useful method compare to previous destructive methods and effective diagnosis method in power system that requires on-line/on-site diagnosis. But partial discharges have very complex characteristics of discharge pattern, so it is required continuous research to development of precise analysis method. In recent, the study of partial discharge is carrying out discover of initial defect of power equipment through condition diagnosis and system development of degradation diagnosis using HFPD(High Frequency Partial Discharge) detection. In this study, simulated system is manufactured and HFPD occurred from those simulator is measured with broad-band antenna in real time, the degradation grade of system is analyzed through produced patterns in simulated target according to the AI/statistics processing.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.649-661
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• 2008

The impact of the detailed surface data on regional meteorological fields in complex coastal area is studied using RAMS. Resolutions of topography and land use data are very important to numerical modeling, because high resolution data can reflect correct terrain height and detail characteristics of the surface. Especially, in complex coastal region such as Gwangyang area, southern area in Korean Peninsula, high resolution topography and land use data are indispensable for accurate modeling results. This study investigated the effect of resolutions of terrain data using SRTM with 3 second resolution topography and KLU with 1 second resolution land use data. Case HR was the experiment using high resolution data, whereas Case LR used low resolution data. In Case HR, computed surface temperature was higher than Case LR along the coastline and wind speed was $1{\sim}2m/s$ weaker than Case LR. Time series of temperature and wind speed indicated great agreement with the observation data. Moreover, Case HR indicated outstanding results on statistical analysis such as regression, root mean square error, index of agreement.

• Journal of Environmental Science International
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• v.18 no.3
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• pp.271-281
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• 2009

In order to reduce the uncertainties and improve the air flow field, objective analysis using observational data is chosen as a method that enhances the reality of meteorology. To improve the meteorological components, the radius influence and nudging coefficient of the objective analysis should perform a adequate value on complex area for the objective analysis technique which related to data reliability and error suppression. Several numerical experiments have been undertaken in order to clarify the impacts of the radius influence and nudging coefficient of the objective analysis on meteorological environments. By analyzing practical urban ground conditions, we revealed that there were large differences in the meteorological differences in each case. In order to understand the quantitative impact of each run, the Statistical analysis by estimated by MM5 revealed the differences by the synoptic conditions. The strengthening of the synoptic wind condition tends to be well estimated when using quite a wide radius influence and a small nudging coefficient. On the other hand, the weakening of the synoptic wind is opposite.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.3
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• pp.269-279
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• 2008

In this paper, an underwater navigation system with adaptive receding horizon Kalman filter (ARHKF) is studied. It is well known that incorrect statistical information and temporal disturbance invoke errors of any navigation systems with Kalman filter, which makes the autonomous navigation difficult in real underwater environment. In this context, two kinds of problems are herein considered. The first one is the development of an algorithm, which estimates the noise covariance of a linear discrete time-varying stochastic system. The second one is the implementation of ARHKF to underwater navigation systems. The performance of the derived estimation algorithm of noise covariance and the ARHKF are verified by simulation and experiment in the towing tank of Seoul National University.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1612-1617
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• 2004

Unbalance analysis is essential in the rotor system. However, some problems still remain in the aspects of computational efficiency and accuracy. In the present paper a new method is proposed for estimating the mass unbalance of a rotating shaft by using the vibration signals. This is an advanced new method for the detection of a mass unbalance and its phase position. Based on the signal processing with FFT, an estimator is designed to detect the mass of unbalance. And an improved Lissajous diagram is also introduced with statistical analysis, which make it possible to compute the phase position of the mass unbalance efficiently and arranged at a certain location of the shaft. The proposed method is demonstrated and validated through several test examples.

• 한국데이터정보과학회:학술대회논문집
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• 2005.10a
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• pp.35-45
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• 2005

Data fusion is method to combination data. The purpose of this study is to design and implementation for street fashion information analysis system using data fusion. It can offer variety and actually information because it can fuse image data and survey data for street fashion. Data fusion method exists exact matching method, judgemental matching method, probability matching method, statistical matching method, data linking method, etc. In this study, we use exact matching method. Our system can be visual information analysis of customer's viewpoint because it can analyze both each data and fused data for image data and survey data.

• Architectural research
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• v.14 no.3
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• pp.109-116
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• 2012

In order to shorten construction duration in high-rise project, construction company tried to make various system method toward simplifying construction method and shortening construction duration. Though high-rise tower-type residential project are growing, there are few case study. Then, the data for preliminary schedule planning in high-rise tower-type residential project are rare. This purpose of research shows construction method in structural work in high-rise tower-type residential project, suggests schedule planning in structural work through case studies. The structural work in high-rise tower-type residential project was divided 1) completion of form in lower part and 2) the typical floor under penthouse. The statistical analysis were done in two parts, the data from analysis were used in simulation. Finally, researcher confirmed the difference between real construction duration and the figure from simulation. The results shows that the more construction duration is long, the less ACS's cost is low. It means the effectiveness is increasing in ACS, if the floor number is high.

• Journal of the Korean Home Economics Association
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• v.36 no.4
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• pp.35-48
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• 1998

The imputation of monetary value of women's contribution to the informal economy for inclusion in satellite accounts to the formal System of National Accounts has been attempted along many methods. This is bases on official laborforce statistics and time-use survey. In this statistical system, household work is not an economic activity(or productive labor). Also, the clssification of activities involved in household work is different from that of sampling survey relating evaluation. The measurement of women's unpaid work is one of the important tasks for the improvement of women's status and the establishment of a development policy. To measure unpaid work in the economic terms, we should take following measures; 1) develop satellite or other official accouts to measure unpaid work outside national accounts. 2) conduct a nation-wide time-use survey to measure the unpaid work. 3) develp a proper classificaition of activities for time-use statistics. 4) reexamine the minimum time criterion. 5) determine a proper method of valuing along the law system.

• Journal of the Korea Safety Management & Science
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• v.11 no.3
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• pp.227-237
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• 2009

After enterprise get a certification in acquisition, the core requirements of ISO/TS 16949 standard is pull out the Performance Indicators by process access approach during the settlement and operation of system, and the pulled key performance indicators classified into the customer intention process, support process and management process and analyzed the effect to the management result. This study conducted with following step. Firstly, preceding research, the literature and investigation analysis about process approach method which is the special characteristics of ISO/TS 16949 standard. Secondly, each process of ISO/TS 16949 standard is classified and deduced the key performance indicators followed process access method. Finally, get a enterprise survey data related to improvement of Performance Indicator and analyzed by SPSS statistical software.

• IE interfaces
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• v.20 no.1
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• pp.11-20
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• 2007

This case study aims to embody the requirement of the make-to-order type manufacturer who wants to manage risks effectively when decisions are required to be taken under a risk. First, we present a method for choosing the risk factors that should be controlled for the make-to-order type manufacturer. Subsequently, those factors have been verified using statistical methods such as the ANOVA test. The process flows to be operated with the selected risk factors and the rules for an early warning system have been proposed. For a couple of factors, a prototype system has been developed to illustrate actual applications. Applications of the technique developed here for other types of manufacturers might be an interesting research problem.