• Journal of Satellite, Information and Communications
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• v.6 no.1
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• pp.63-67
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• 2011

This paper analyzes the interference effect of ISM(Industrial Scientific Medical) equipment on WLAN in order to protect WLAN in interference environment which WLAN Station is close to ISM equipment. CISPR(International Special Committee on Radio Interference) radiation limit standard was used for interfering power of ISM equipment. Then, MCL(Minimum Coupling Loss) which is for the worst case and MC(Monte Carlo) which is based on statistic interference probability are used to get protection distance. As a result, the protection distance of 105 m was calculated by using MCL for the worst case. And, the protection distance of 17 m was calculated by using MC for statistic analysis.

• Journal of the Korean Society of Safety
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• v.27 no.1
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• pp.32-43
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• 2012

"low and old age trend" is a big social national problem in korea but also in foreign countries. The Government pursues a policy for aged people to take part in construction site as labours. Low childbirth and avoidance of 3D work kinds lead to exposure of aged workers to industry work places. According to korea department of labour, it is expected that 18% of total economic activity people in 2008 to 27.2% in 2018 be increased with age of more than 55 old years. Therefore, It is needed that more countermeasures for old workers should be taken for safer work conditions. This old workers with more than 55 old years contain major portion of accident occurrence in construction industry. It is found that accident rate in construction industry can be decreased if appropriate technical safety training is provided to them who wish to work at construction sites. Statistic analysis such as frequency, cross, logistic regression using program package SPSS 13.0 has been made after collecting questionnaire survey of more than 330 workers at construction sites.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.274-277
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• 2011

We measured a solar irradiation of vertical and horizontal surface per azimuth in southern area of Korea using pyrheliometer. In comparison with the provided data from ASHRAE and CIBSE, the average amount of solar irradiation has much variation of 10 to 150% in reference with north direction. In the clear day, the measured value has much difference with the value of ASHRAE and there is similar trend in case of CIBSE. The reason why amount of irradiation of clear day is differ from the average value, is able to be assumed that the value of ASHRAE and CIRSE is made of assumption based on clear days. The result of analysis of ASHRAE and CIBSE values according to the amount irradiation value for vertical and horizontal surface per azimuth using the MBE, RSME, and t-Statistic show that the CIBSE value has more reliability for the MBE, RMSE, and t-Statistic values than ASHRAE value.

• KIEAE Journal
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• v.7 no.6
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• pp.23-28
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• 2007

Limited fossil fuels and unstable energy supply are considered as one of the critical problems in architecture requiring large amounts of energy. In order to this challenge, environment-friendly architecture design is required. Clear data should be prepared to apply solar energy to architecture aggressively and properly. This study used FS statistical analysis data regarding average daily solar radiation of Seoul observed over 20 years to find out standard year and standard daily solar radiation. This study also aims to compare and evaluate an appropriate method of selecting a standard year which is too close to measurement value through comparison and analysis with daily solar radiation acquired by applying overseas researchers' suggesting weight factor. As a result, the data nearest to measurement value of daily solar radiation was UK CIBSE TRY(TYPE 2) displaying 0.100in t-statistic index. For UK CIBSE TRY(TYPE 2), weight factor was applied to three climatic elements except relative humidity. TYPE 1 and TYPE 3 recorded 0.343 and 0.367, respectively, showing higher record of t-statistic than TYPE 2. TYPE 1 was calculated through FS statistical value of single data about daily solar radiation with other climatic elements excluded. For TYPE 3, relative humidity was added to TYPE 2. In particular, since TYPE 2 was closer to the measurement value compared to the others, it is necessary to consider relationship with other climate elements if other climate elements are added.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.6
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• pp.1195-1202
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• 2016

Recently, a lot of studies that applying the big data technology to various fields, are progressing actively. In the maritime domain, the big data is the meaningful information which makes and gathers by the navigation and communication equipment from the many ships on the ocean. Also, importance of the maritime safety is emphasized, because maritime accidents are rising with increasing of maritime traffic. To support prevention of maritime accidents, in this paper, we developed a vessel traffic display and statistic system based on AIS messages from the many vessels of maritime. Also, to verify the developed system, we conducted tests for vessel track display function and vessel traffic statistic function based on two test scenarios. Therefore, we verified the effectiveness of the developed system for vessel tracks display, abnormal navigation patterns, checking failure of AIS equipments and maritime traffic statistic analyses.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.151-156
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• 2018

The purpose of this study is to conduct a meta-analysis of 18 papers that can be verified among the papers on the subject of TPM. Five hypotheses were set for the analysis and meta - analysis was carried out with CMA as presented in each research paper. As a result of analysis, I-square value is more than 75% in four hypotheses. Therefore, the null hypothesis that the size of the population effect is the same for all studies was rejected. The reason for the heterogeneity is that the research characteristics such as the distribution of the respondents, the study conditions, the study period, and the study area are different. In this case, a summary statistic of the individual studies that can be classified according to the characteristics of the research is needed to analyze the effect size difference. However, individual studies do not provide a summary statistic that can classify the effect differences, so it is not possible to analyze the causes of heterogeneity.

• Journal of the Korean Statistical Society
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• v.34 no.3
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• pp.173-183
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• 2005

The Box-Cox power transformation is generally used for variance stabilization. Recently, Shin and Kang (2001) showed, under the Box-Cox transformation, invariant properties to the original model under the large mean and relatively small variance assumptions in time series analysis. In this paper we obtain some invariant properties in spatial statistics. Spatial statistics, Invariant Property, Variogram, Box-Cox power Transformation.

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.25-32
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• 1999

A single outlier can influence on the least squares estimators and can invalidate analysis based on these estimators. The Cook's statistic has been introduced to measure influence of individual data point on parameter estimation and the quantile of the F distribution is recommended as a reference value. but in practice subjective judgement is applied in the choice of appropriate quantile. A simple reference value is introduced in this paper which is developed by approximating conditional quantities of Cook's measure. The performance of the proposed criterion is evaluated through analysis of real data set.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.7 no.1
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• pp.91-99
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• 1999

On the basis of KTMPO visibility data measured for 17 years(Jan.1983 to Oct.1999), time-series data analysis is accomplished for regression trend, cyclical periodicity, dependency of these data in this paper. After that, to predict visibility in KIMPO international airport a probability model is presented using this statistic probability characteristics.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.1098-1101
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• 1993

The purpose of this work is to build a fuzzy model of a batch culture for a process control. The process is highly nonlinear system with large delay. This paper presents two methods of modeling the process behavior. One is a method of recognizing them by fuzzy rules that are contracted by the pattern analysis in consideration of skilled operators' way. The other is a method of predicting them by approximate linear models and fuzzy rules by statistic analysis.