• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.1245-1249
• /
• 2009

본 연구에서는 우리나라 수문기상인자의 특성변화 분석의 필요성을 지각하여 국내 기상관측소 중 관측년수가 30년 이상인 관측소 63개 지점에 대한 수문기상인자 중 연평균기온, 연평균상대습도, 연강수량, 연증발량, 연일조시간, 연강수계속시간, 연강수일수, 연적설일수, 연신적설일수 등의 자료를 수집하고 기본통계량에 해당하는 평균, 표준편차, 왜곡도, 변동계수를 통하여 수문기상인자의 경년적 변화를 파악하였다. 또한 각종 통계학적 기법을 이용하여 이들 수문기상인자의 경향성, 주기성, 변동성 등을 분석하였으며, 그 결과는 우리 나라를 대표할 수 있는 서울지점을 중심으로 정리하였다. 기본통계량을 분석한 결과 연강수량, 연강수일수, 연강수계속시간의 표준편차와 변동계수가 다른 수문기상인자 비해 상대적으로 큰 것으로 나타나 강수관련 인자들의 경년별 변화가 두드러짐을 알 수 있다. 또한 선형회귀분석과 5년 이동평균 결과 연강수량과 연평균기온은 증가, 연평균상대습도, 연일조시간, 연강수일수, 연증발량은 감소하는 경향을 보였다. Mann-Whitney Test, Wald-Wolfowitz Test, Hotelling-Pabst Test, Wavelet Method와 같은 통계학적기법으로 동질성, 독립성, 검정, 경향성 검정을 수행한 결과 연강수량, 연증발량, 연강수계속시간, 연강수일수, 연적설일수, 연신적설 일수 인자가 각각의 검정에서 동질성 및 독립성을 보였고, 경향성 검정에서는 연평균기온, 연평균상대습도, 연적설일수 인자가 신뢰수준 내에서 유의함을 보였고, 주기성 검정결과 본 연구에 채택한 9개의 수문기상인자들의 연속된 주기성은 나타나지 않았다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.8
• /
• pp.2468-2479
• /
• 1996

An upper bound solution is obtained to perform the process analysis of hot strip rolling process. The material flows within the roll bite at various geometries and frictional conditions are obtained from finite element analysis and the typical flow pattern which is necessary to determine the kinematically admissible velocity field is assumed. From the kinematically admissible velocity field, the upper bound energy is calculated and the rolling load, angle of neutral point and forward slip ratio at various operational conditions are obtained from upper bound energy. The process analysis of above mentioned parameters at various operational conditions have provided valuable information which is hard to obtain during rolling operation and the predicted ranges of quantitive values from these analyses lie whthin the bound of actual operational data.

• Tuberculosis and Respiratory Diseases
• /
• v.49 no.6
• /
• pp.684-690
• /
• 2000

Background : The most common cause of treatment failure of pulmonary tuberculosis is early stoppage of treatment or irregular medication. The most important aspect of a retreatment is regular medication provided over a long period. Inadequate treatment may cause drug resistance and prolong the duration of chemotherapy. This study analyzed the risk factors of pulmonary tuberculosis patients, who failed in retreatment, and to use the results as basic data in the management of intractable tuberculosis patients with improving the rate of retreatment success. Methods : We performed a retroactive study of 62 pulmonary tuberculosis patients in retreatment at National Mokpo Tuberculosis Hospital from Jan. 1994 to Dec. 1995. The patients were separated into two groups: group I was retreatment failure and group II was retreatrnent success. For the analysis of risk factors in retreatment failure, we compared the difference between the two groups and tested the confidence limit about results of the results by independent t-test, ${\chi}^2$ test and Fisher's exact test. Results : The treatment failure rate of retreatment patients was 13(21%), and treatment success 49(79%). No significant difference (p>0.05)in age, sex, number of treatment, irregular rate of treatment, extent of the disease & cavitary lesion on the chest X-ray, number of resistance drugs, number of used drugs to medication, number of sensitive bactericidal drugs to medication, rate of sensitive drugs to medication and resisiance to INH & RFP had not significant difference. was found. However, the number of treatment was $2.4{\pm}0.8$ in group I and $1.6{\pm}0.9$ in group II, and had showing a significant difference(p<0.05) between the two groups. Conclusion : The risk factor of retreatment failure was more irregular previous treatment the irregularity of the previous treatment. For reducing the retreatment failure of pulmonary tuberculosis, greater efforts are needed more need to be done to prevent failure of first treatment.