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        검색결과 313

        281.
        2008.12 KCI 등재 서비스 종료(열람 제한)
        본 논문에서는 월별 해양사고건수를 이용하여 국내 해역의 해양사고에 관한 통계적인 기초분석을 수행하였다. 이를 위해서 해역간 해양사고건수의 차이여부, 연간 해양사고건수의 차이여부, 그리고 월간 해양사고건수의 차이여부 등을 국내 해역별 및 어선과 비어선으로 나누어 일원분산분석을 통해 확인하였다. 그리고 추가적으로 사후분석을 수행하여 분석그룹에 대한 평균차이의 검정을 하였다 결론적으로 해역간 사고건수에는 서해, 남해, 그리고 동해순으로 많았고 서로 유의한 차이가 있었다. 연간 사고건수의 차이에서는 어선의 경우 남해와 동해에서, 비어선의 경우 남해에서 유의한 차이가 나타났다. 또한 월간 해양사고건수에 대한 차이에서는 어선에 대해서만 서해와 동해에서 서로 유의한 차이를 보였다.
        282.
        2008.10 KCI 등재 서비스 종료(열람 제한)
        하천유량의 시간적 추세에 대한 이해는 자연환경이나 인간사회를 위한 하천관리 및 수자원계획에 도움을 줄 수 있다. 일반적으로 기온, 강수, 유량 그리고 농업, 홍수방지활동, 저수지 및 유역간의 물이동 등과 같은 하천의 이용은 결과적으로 하천의 흐름에 반영되게 된다. 수자원 시설물 설계에서 받아들여지는 시계열 상에서 수문기상학적 특성이 불변하다는 가정은 기후변화나 하천교란에 의해 더 이상 타당하지 않을 수 있다. 그러므로 수문시계열에서 변화 특성을 검증하고
        283.
        2008.06 KCI 등재 서비스 종료(열람 제한)
        In order to support the development of wind farms in Jejudo, a wind resource database for Jejudo has been established using a meteor-statistical analysis of KIER(Korea Institute of Energy Research) met-mast measurements and KMA(Korea Meteorological Administration) weather data. The analysis included wind statistics, tower shading, an exposure category classification using satellite images, the effect of atmospheric stability on the wind profile exponent, and a correlation matrix of wind speed to gain an understanding of the meteorological correlation between long-term weather observation stations and short-term met-mast measurements. The wind resource database for Jejudo, is to be provided as an add-on to Google EarthTM, which is expected to be utilized as a guideline for the selection of an appropriate reference site for long-term correction in the next wind farm development project.
        286.
        2008.04 KCI 등재 서비스 종료(열람 제한)
        Statistical analysis technique was applied to operating parameters and removal efficiency data sets obtained from advanced wastewater treatment plant during 1 year. Through factor analysis three factors derived varimax rotation were selected each plant. Three components explained 96%, 87% of the total variance of the process, respectively. The components on A2O plant were identified in the following order:1) Shortening the SRT during high-flow period, 2) Keeping biomass high on winter 3) factor was related to DO. On DNR plant, we defined them as follows: factor 1, Prolonged the SRT during high-flow period; factor 2 was related to sludge return; factor 3, Influent BOD during low-DO period. This technique was believed to assist operators in identifying priorities to improve operation efficiency.
        287.
        2008.03 KCI 등재 서비스 종료(열람 제한)
        This experiment was carried out to evaluate the agronomic stability of North Korean rice varieties using the statistical model developed by Grafius, Finlay, and Ever hart. The lowest yearly variation based on coefficients of variation was found in Hannam 29 for number of panicles per hill, in Sijoong 9 for number of grains per panicle, in Pyeongyang 3 for ripened grain ratio, in Sijoong 16 for 1,000 grain weight, and in Yeomju 1 for grain yield. By Grafius's model, Pyeongbook 3, Weonsan 66 in early maturing groups and Seohaechalbyeo in medium maturing groups show stable for 3 years. Weonsan 66 in early maturing groups and Seohaechalbyeo in medium maturing groups were found to be highly stable as analyzed by both Finlay and Wilkinson's model and Everhart & Russell's model. With reference to three models, Weonsan 66 was highly stable for 3 years with showing more yield than Odaebyeo in early maturing groups while Seohaechalbyeo was highly stable for 3 years with showing high yield than Hwaseongbyeo in medium maturing groups above 5~;t~;ha-1 of milled rice respectively.
        288.
        2007.12 KCI 등재 서비스 종료(열람 제한)
        Heavy metal concentrations in the soil were investigated for the abandoned Samkwang metal mine, Cheongyang-Gun, Chungnam Province, Korea. The concentrations of heavy metal(As, Cd, Cu, Ni, Pb, Zn) were determined in mine soils collected at the abandoned mine sites to obtain a general classification and specification of the pollution in this highly polluted region. The results estimated with the normal test and basis statistic on the central tendency and variation showed that the distribution of heavy metal concentration had significantly different at the range of all locations. The range of spatial distribution on the relationship of heavy metal concentration and pH was 4.8∼8.8 and heavy metal concentration on the type of land use was highest in forest land, and also Ni and Zn in farm and rice field showed the high concentration. The distribution of heavy metal concentration on the depth of a soil showed that the metal concentrations in subsoil were higher than of those in surface soil, while the concentration of Cu and Ni had no significant difference on the depth of soil. Results from the correlation analysis using the data except the extreme and unusual data revel that Zn-Cd(r=0.867), Zn-As(r=0.797), Zn-Pb (r=0.764), Cu-Cd(r=0.673), Cu-As(r=0.614) and Zn-Ni(r=0.605) were the most important parameters in assessing variations of heavy metal in soil. To discriminate pattern differences and similarities among samples, principal factor analysis(PFA) and cluster analysis(CF) were performed using a correlation matrix. This study suggests that PFA and CF techniques are useful tools for identification of important heavy metal and parameters. This study presents the necessity and usefulness of multivariate statistical assessment of complex databases in order to get better information about the quality of soil and gives the basis information to clean up the abandoned mine sites.
        289.
        2007.10 KCI 등재 서비스 종료(열람 제한)
        This paper represents the statistical characteristics of sources and receptors for road traffic noise in apartment complex. Also we suggested that the site-specific characteristics of vertical and horizontal distributions in the complex apartment have been derived using a different analysis for evaluating levels of Leq1h by the apartment floor at a given distance from a road in terms of the flow rate, the mean speed of the traffic, and the percentage of the type vehicles in the day and night periods. As a result, the contribution orders of traffic quantity by the type of vehicles showed as followed: light vehicle>medium vehicle>heavy vehicle>motorcycle. Especially, the mixing ratio of entering the road on the heavy vehicle in the daytime was two times higher than that of in the night. The speed in all types of vehicle is in the range of 41 and 81 km/hr and noise level was not significantly different in day and night-time. The sources of road traffic noise had different variations and uncertainties using a random variable and probability distribution. The sound distribution to receptors by the apartment floor showed S curve between 1st floor and 15th floor With the normality test, the normal distributions using Anderson-Darling Test followed 1st, 3th, 13th and 15th floor in the daytime and all floors except 7th floor in the night (p>0.05). And also, the value of the pearson correlation coefficient (r) obtained in this study have significantly different at the range of floor. In conclusion, the results suggested that the distribution characteristics of levels of Leq1h on the sources and receptors of road traffic noise in apartment complex must be improved and developed on the guideline of regulation of road traffic noise.
        290.
        2007.09 KCI 등재 서비스 종료(열람 제한)
        현장에서의 레디믹스트 콘크리트(이하 레미콘) 품질에 대한 신뢰도의 정량적 평가를 위해 동일 규격 레미콘에 대하여 타설시기에 따른 슬럼프값, 공기량, 염분함유량 및 재령에 따른 압축강도의 품질 특성값의 변동정도를 비교하고 각각의 시험값들을 통계적인 분석도구를 이용하여 그 품질변동 요인 및 품질값을 분석하였다. 이러한 분석 결과를 통해 7일강도와 28일강도 사이의 상관식과 공기량 및 슬럼프의 품질 신뢰도를 파악하였으며 이에 대한 결과 고찰 및 콘크리트 품질 확보를 위한 관리방안을 모색하고자 하였다.
        291.
        2006.12 KCI 등재 서비스 종료(열람 제한)
        The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons) × 2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least 5∼9 members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major 5∼8 non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.
        292.
        2006.03 KCI 등재 서비스 종료(열람 제한)
        The purpose of the study was to find out what the lavender aroma have an influence on changes in human brain electroencephalogram(EEG). We have conducted an experiment on 10 men and women in their twenties. After comparing digtal EEG(dEEG) with statistical EEG(SEEG) that put advantages of two methods together was applied to this experiment. The measurement was made through 19 channels using 32 channel digital EEG system, and it was made for 20 seconds with the sampling rate set to be 250 Hz. Then the part, which was not polluted by artifact, was adopted. After a clinician judged, the data without the artifact were gathered from the ones, which were measured 9 times in 19 channels, to construct statistical data base. Lavender fragrance had such an influence that δ wave was found in frontal lobe and temporal lobes of both side brains(FP1, FP2, T7, T8, F7, F8, C3, C4, Cz, F3, F4). This can be considered a characteristic of lavender, and more study on another effects of it should be continued. The influence of lavender aroma on human brain EEG will contribute to reducing the stress from which humans suffer.
        293.
        2005.12 KCI 등재 서비스 종료(열람 제한)
        This study designs an integrated data architecture to systematically manage the agricultural statistics database. Managing the agricultural statistics is important since it provides data for policies and decision making for agribusinesses. Ministry of Agriculture and the National Statistical Office collect the basic agricultural statistic data which provides the basis of logical decision making and agricultural policies. However, the agricultural statistic data has not well been used. The data has not been consistently collected nor managed. The raw data has not been organized nor processed to meet various demands. The needs has been arisen for a consistent agricultural statistics system to increase the relevance, accessibility, and efficiency of data for various users. There are massive amount of data accumulated over a long time period. Introducing the new system and reorganizing the data will bear large risks. A systematic method is required to reduce the risks in planing, building, and maintaining the database without hindering administration. This study provides a design of the agricultural statistics system architecture based on the user requirement analysis (URA) and similar systems abroad. We have also build a prototype to check the implementability of the system design.
        295.
        2005.11 KCI 등재 서비스 종료(열람 제한)
        NO2 concentration characteristics of Busan metropolitan city was analysed by statistical method using hourly NO2 concentration data(1998~2000) collected from air quality monitoring sites of the metropolitan city. 4 representative regions were selected among air quality monitoring sites of Ministry of environment. Concentration data of NO2, 5 air pollutants, and data collected at AWS was used. Both Stepwise Multiple Regression model and ARIMA model for prediction of NO2 concentrations were adopted, and then their results were compared with observed concentration. While ARIMA model was useful for the prediction of daily variation of the concentration, it was not satisfactory for the prediction of both rapid variation and seasonal variation of the concentration. Multiple Regression model was better estimated than ARIMA model for prediction of NO2 concentration.
        297.
        2005.02 KCI 등재 서비스 종료(열람 제한)
        Statistical analysis between operating parameters and effluent quality on advanced wastewater treatment plant was performed. Through factor analysis four factors derived varimax rotation were selected each plant. Four components explained 80%, 82% of the total variance of the process, respectively. The components on MLE plant were identified in the following order:1) HRT increase and BOD load decrease by influent decrease, 2) Biomass, 3) SVI increase by internal return increase, 4) Microbial diversity by SRT increase. On A2O plant, we defined them as follows: factor 1, high MLSS by return rate increase, HRT increase by influent decrease; factor 2, biomass; factor 3, BOD of influent; factor 4 was relate to DO.
        300.
        2003.04 KCI 등재 서비스 종료(열람 제한)
        Regional Adaptability Test (RAT) was conducted to select promising breeding lines of rice for cultivation in specif ic regions. Analysis of genotype (G) and genotype by environment (G×E) interaction observed in RAT was carried out to test their adaptabili