• 한국농공학회논문집
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• 제54권4호
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• pp.9-17
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• 2012

This study was aimed to characterize non-point source (NPS) pollutant runoff and estimate event mean concentrations (EMCs) from a small rural watershed located at the headwater area of the Gyeongan stream. The study watershed consists of the two major landuse, forest (72 %) and paddy field (28 %). The nine rainfall events ranging from 18.5 to 192.6 mm in amount were monitored in this study. Stream flow was measured at the watershed outlet using a water level gauge, while a number of water samples for each event were collected and analysed for water quality. Event pollutant loads varied greatly depending on rainfall events varying from 22.6 to 3,134.2 mg/L, 0.32 to 24.56 mg/L, 0.090 to 1.320 mg/L, and 2.3 to 149.8 mg/L for SS, TN, TP, and COD, correspondently. The respective mean EMCs were estimated by 104.2, 1.00, 0.168, and 7.9 mg/L. The Pearson correlation analysis showed that COD EMC was significantly correlated with those of SS, TN, and TP. Rainfall runoff ratio appeared to be negatively correlated with EMCs of SS, TP, and COD, although not statistically significant. The event loads from the largest rainfall was greater than the sum of those from the remaining eight events. The study results suggest that the appropriate management of intensified storm events are of greater importance in curbing NPS loads, while the estimated EMCs provide base data for the unit pollutant loads determination for the forest-paddy composite upstream watershed.

• 한국항공운항학회지
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• 제21권4호
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• pp.77-89
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• 2013

The purpose of this study is to anticipate the air travel demands over the period of 164 months, from January 1997 to August 2010 using ARIMA-Intervention modeling on the selected sample data. The sample data is composed of the number of the passengers who in the domestic route for Jeju route. In the analysis work of this study, the past events which are assumed to have affected the demands for the air travel routes to Jeju in different periods were used as the intervention variables. The impacts of such variables were reflected in the presupposed demand. The intervention variables used in this study are, respectively, the World Cup event in 2002 (from May to June), 2003 SARS outbreak (from April to May), Tsunami in January 2005, and the influenza outbreak from October to December 2009. The result of the above mentioned analysis revealed that the negative intervention events, like a global outbreak of an epidemic did have negative impact on the air travel demands in a risk aversion by the users of the aviation services. However, in case of the negative intervention events in limited area, where there are possible substituting destinations for the tourists, the impact was positive in terms of the air travel demands for substituting destinations due to the rational expectation of the users as they searched for other options. Also in this study, it was discovered that there is not a binding correlation between a nation wide mega-event, such as the World Cup games in 2002, and the increased air travel demands over a short-term period.

• 동서간호학연구지
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• 제11권2호
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• pp.116-123
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• 2005

Purpose: The purpose of this study was to analyze the influencing factors on adolescent's self-efficacy. Method: This was a descriptive study. The data were collected from 7th through 12th graders(N=1710) enrolled in middle schools(N=873) and high schools(N=837) in the metropolitan area of Daegu. The instruments had used for this study were the self-efficacy, the life event checklist, and Family APGAR. The data were analyzed using frequency, t-test, Pearson correlation coefficient, and multiple regression analysis. Result: Pearson correlation analysis revealed that there were negative correlations between the self-efficacy and the stress. However, in case of the subjects who recorded higher scores at self-efficacy they showed higher scores at family function. Stepwise multiple regression analysis revealed that powerful predictors of adolescent's self-efficacy were family function and relations of schoolmate. Conclusion: From these results, we can find that the family function and relations of schoolmate were actual factors theta affected the self-efficacy of adolescents. Accordingly, affirmative emotion in family, harmonic communication among family members and sharing housekeeping works is recommended as a useful method in order to enhance the family function, and then the self-efficacy of adolescence will be increased.

• 대기
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• 제22권1호
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• pp.57-71
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• 2012

Influences of orographic and ocean effect, which depend on the detailed geographic characteristics, upon winter time (December-February) precipitation in the Yeongdong region are investigated. Most of precipitation events in the Yeongdong region during the wintertime are associated with moist northeasterly (coming from the northeast direction) winds and also the spatial distribution of precipitation shows a great difference between Mountain area (Daegwallyeong) and Coastal area (Gangneung). The linear correlation coefficient between the meteorological variables obtained from NCEP/NCAR Reanalysis Data and precipitation amount for each precipitation type is calculated. Mountain type precipitation is dominated by northeasterly wind speed of the low level (1000 hPa and 925 hPa) and characterized with more precipitation in mountain area than coastal area. However, Coastal type precipitation is affected by temperature difference between ocean and atmosphere, and characterized with more precipitation in coastal area than mountain area. The results are summarized as follows; In the case of mountain type precipitation, the correlation coefficient between wind speed at 1000 hPa (925 hPa) and precipitation amount at Daegwallyeong is 0.60 (0.61). The correlation is statistical significant at 1% level. In the case of coastal type precipitation, the correlation coefficient of temperature difference between ocean and 925 hPa (850 hPa) over the East sea area and precipitation amount at Gangneung is 0.33 (0.34). As for the mountain type precipitation, a detailed analysis was conducted in order to verify the relationship between precipitation amount at Daegwallyeong and low level wind speed data from wind profiler in Gangneung and Buoy in the East Sea. The results also show the similar behavior. This result indicates that mountain type precipitation in the Yeongdong region is closely related with easterly wind speed. Thus, the statistical analysis of the few selected meteorological variables can be a good indicator to estimate the precipitation totals in the Yeongdong region in winter time.

• 한국지진공학회논문집
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• 제25권2호
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• pp.53-58
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• 2021

Nuclear power plant's safety against seismic events is evaluated as risk values by probabilistic seismic safety assessment. The risk values vary by the seismic failure correlation between the structures, systems, and components (SSCs). However, most probabilistic seismic safety assessments idealized the seismic failure correlation between the SSCs as entirely dependent or independent. Such a consideration results in an inaccurate assessment result not reflecting real physical phenomenon. A nuclear power plant's seismic risk should be calculated with the appropriate seismic failure correlation coefficient between the SSCs for a reasonable outcome. An accident scenario that has an enormous impact on a nuclear power plant's seismic risk was selected. Moreover, the probabilistic seismic response analyses of a nuclear power plant were performed to derive appropriate seismic failure correlations between SSCs. Based on the analysis results, the seismic failure correlation coefficient between SSCs was derived, and the seismic fragility curve and core damage frequency of the loss of essential power event were calculated. Results were compared with the seismic fragility and core damage frequency of assuming the seismic failure correlations between SSCs were independent and entirely dependent.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.463-467
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• 2015

Mega-shock means a sporadic event such as the earning shock, which occurred by sudden market changes, and it can cause serious problems of profit loss of international construction projects. Therefore, the early response and prevention by analyzing and predicting the Mega-shock is critical for successful project delivery. This research is preliminary study to develop a prediction model that supports market condition analysis and Mega-shock forecasting. To avoid disadvantages of classic statistical approaches that assume the market factors are linear and independent and thus have limitations to explain complex interrelationship among a range of international market factors, the research team explored the Fractal Theory that can explain self-similarity and recursiveness of construction market changes. The research first found out correlation of the major market factors by statistically analyzing time-series data. The research then conducted a base of the Fractal analysis to distinguish features of fractal from data. The outcome will have potential to contribute to building up a foundation of the early shock warning system for the strategic international project management.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2011년도 춘계학술대회
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• pp.89-90
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• 2011

이 연구는 해양레저 전시이벤트의 평가속성이 방문객 만족도 및 재구매 행동에 미치는 영향을 실증적으로 분석해 해양레저 전시이벤트의 효과적인 마케팅 및 경영 전략 수립의 기초자료를 제공하기 위해 수행되었다. 이러한 연구목적을 달성하기 위해 2010년 10월 G도에서 개최한 대한민국국제요트대전의 방문객 300명을 편의표본추출법을 통해 조사대상으로 선정하고 현장 설문조사를 통해 자료를 수집하였다. 유효설문지 286부를 기술통계, 요인분석, 상관관계분석 그리고 다중회귀분석을 통해 다음과 같은 결론을 도출하였다. 첫째, 해양레저 전시이벤트의 평가속성은 방문객 만족도에 유의한 영향을 미치고 있었으며($R^2$=.260, p=.000), 평가속성 중 행사(${\beta}$=.300, p=.000) 요인만이 만족도에 영향을 미치고 있었다. 둘째, 해양레저 전시이벤트의 평가속성은 방문객의 재구매 행동에 유의한 영향을 미치고 있었으며($R^2$=.274, p=.000), 평가속성 중 행사(${\beta}$=.293, p=.000), 교통(${\beta}$=.180, p=.010) 그리고 종사원(${\beta}$=.134, p=.047) 순으로 상대적 영향력을 미치고 있었다.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제2권2호
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• pp.83-92
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• 2013

RSA-CRT는 RSA전자서명 알고리즘의 고속화 구현을 위해 가장 많이 사용되고 있는 알고리즘으로, 스마트디바이스에 사용되는 RSA-CRT 알고리즘의 물리적 취약성 검증을 위해 CRT의 각 단계 연산에서 다양한 부채널 분석 이론이 발표되어 왔다. 본 논문에서는 RSA-CRT 구현에 사용되는 뺄셈연산의 이벤트 정보를 활용하여 RSA-CRT의 reduction알고리즘을 분석하는 새로운 SAED(Subtraction algorithm Analysis on Equidistant Data)분석 방법을 제안한다. SAED분석 방법은 알고리즘에 의존한 전력 변화를 이용한 분석 방법이며, 뺄셈 연산을 차분전력분석 방법으로 분석하여 키를 찾아낸다. 본 논문은 SAED분석 방법의 이론적인 합리성을 증명하고, 실험적으로 기존의 분석 방법보다 향상된 결과를 가짐을 보인다. 실험 결과 256개의 파형만으로 하나의 바이트를 분석해 낼 수 있어, 기존 논문보다 효율적인 분석 방법임을 확인 할 수 있었다.

• 한국조리학회지
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• 제14권2호
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• pp.99-114
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• 2008

The purpose of this study is to examine the relationships between each type of attitudes toward money and the attributes of choosing family restaurants. A self-administrated questionnaire was completed by 387 students, and data were analysed by frequency, factor, reliability and canonical correlation. Seven factors were obtained from factor analysis of attitudes toward money; Factor 1 "power", Factor 2 "obsession", Factor 3 "retention", Factor 4 "achievement", Factor 5 "anxiety", Factor 6 "distrust", and Factor7 "evaluation". The attributes of family restaurant choice were extracted into six factors: Factor 1 "quality of food", Factor 2 "restaurant event", Factor 3 "interior environment", Factor 4 "value of food", Factor 5 "convenience for approach", and Factor 6 "employees' service". Canonical correlation analysis showed three significant functions. Canonical function 1 showed that the attitudes of considering the power of money, its retention and achievement were indicated to have significantly positive relationships with the quality of food in the attributes of choosing family restaurants. Canonical function 2 showed that significantly negative relationships between distrust and restaurant events and convenience for approach. Canonical function 3 also showed that significantly positive relationships between obsession and anxiety and the interior of restaurants and employees' service, and significantly negative relationships between evaluation and the interior of restaurants and employees' service.

• Journal of Astronomy and Space Sciences
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• 제19권2호
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• pp.133-140
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• 2002

다목적 실용 위성 1호는 1999년에 발사되어 운용되고 있으며 , 과학 탑재체로 우주과학센서(Space Physics Sensor)를 탑재하고 있다. 이중 SPS IMS는 2000년 6월부터 2001년 8월에 이르는 태양 활동 극대기 동안 지구 이온층에 관한 정보를 지상으로 전송하였다. 다목적 실용위성 1호가 적도지 역을 통과할 때 전자 밀도가 급격 히 감소하는 플라즈마 밀도 불균일 현상(equatorial bubble)이 자주 관측되었다. SPS IMS가 운용된 기간 동안의 데이터를 통계적으로 분석 한 결과, equatorial bubble 현상은 지구 자기장의 크기가 약한 대서양 지역에서 자주 일어났고, 또한 Kp 간이 낮을 때에 더욱 빈번하게 발생하였다. 이는 기존의 DMSP위성을 통한 관측 결과 및 페루 지역의 라디오 관측 결과 등과 상당한 수준의 일치를 보이고 있다. 밀도 불균일 지역 내의 전자 온도 변화는 전자 밀도 변화와 다양한 상관 관계를 나타낸다.