• 한국대기환경학회지
• /
• 제24권6호
• /
• pp.649-661
• /
• 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.

• 한국환경과학회지
• /
• 제18권3호
• /
• pp.271-281
• /
• 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.

• 대한조선학회논문집
• /
• 제45권3호
• /
• pp.269-279
• /
• 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
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.1612-1617
• /
• 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
• /
• 한국데이터정보과학회 2005년도 추계학술대회
• /
• pp.35-45
• /
• 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
• /
• 제14권3호
• /
• pp.109-116
• /
• 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.

• 대한가정학회지
• /
• 제36권4호
• /
• pp.35-48
• /
• 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.

• 대한안전경영과학회지
• /
• 제11권3호
• /
• pp.227-237
• /
• 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.

• 산업공학
• /
• 제20권1호
• /
• pp.11-20
• /
• 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.

• 한국농림기상학회지
• /
• 제23권4호
• /
• pp.415-423
• /
• 2021

NCAM-LAMP 중기예측 자료의 통계적 후처리와 개선을 위하여 R 기반의 지점 시계열 자료 검증 체계를 구축하였다. 이 시계열 검증체계를 이용하여 기상청 AWS 관측 자료와 NCAM-LAMP, KMA GDAPS 중기예측 모델 자료를 비교하였다. 이를 위해 관측 지점에 가장 근접한 모델 위도 및 경도 자료를 추출하여 총 9개 지점을 선정하였다. 각 지점에 대해 NCAM-LAMP, GDAPS 모델의 기온, 강수량, 풍속 일평균 예측 자료를 관측과 비교한 결과, 모델들은 풍속의 과대예측 경향을 뚜렷이 보였으며, 기온과 강수의 경우에는 두 모델의 예측력이 월별 및 변수별로 다르게 나타났다. 이를 바탕으로 본 연구에서는 통계적 기법을 개발하여 NCAM-LAMP가 가지고 있는 오차를 줄이고자 하였다. 모델 오차를 줄이기 위해 일반적으로 쓰이는 MOS(Model Output Statistics)기법 중에 인공지능 SVM(Support vector machine) 방식을 8~10월 기간에 적용한 결과, 8월에 비해서 10월이, 기온 변수에 비해서 바람과 강수 변수가 개선된 효과를 보여주었다. 이러한 결과는 풍속의 과대예측을 줄이고, 농림 가뭄지수와 산사태 예측 등을 개선시키며, 지역 수치예보 모델이 시간 적분됨에 따라 영역 내 예측가능성이 점점 저하되는 현상을 완화시키는데 SVM 방법이 일정 부분 기여할 수 있음을 가리키며, 현업 표출 중인 NCAM Agro-Meteogram 개선에도 도움을 줄 것으로 기대된다.