• 대한토목학회논문집
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• 제40권5호
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• pp.465-475
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• 2020

서울, 부산, 대구, 대전, 광주 5개 대도시와 그 외 산청과 영천지점의 강우자료를 이용하여 Box-Cox변환기법에 의한 I-D-F곡선을 유도하였다. Box-Cox변환기법의 실용성은 여러 학문분야에서 검증받은 기법으로 분석 자료가 일반 빈도해석을 수행하기에 부족하여 적절한 확률밀도함수를 도출하지 못할 경우에도 사용가능하기 때문에 적용성 측면에서 전통적인 빈도해석 방법보다 확장성이 크다. 전술한 7개 지점의 전체지속기간 강우자료(10분~1440분)와 짧은 지속기간(20분, 30분, 40분, 50분) 강우자료가 누락될 경우의 강우강도를 비교했을 때 100년 빈도 이하 지속기간 10분~60분에서 -23.0~14.7 %의 상대오차가 있었다. 이에 따라 강우분석 시 짧은 지속기간(20분, 30분, 40분, 50분) 강우자료를 포함하여 I-D-F곡선을 유도함이 요구되며 짧은 지속기간(20분, 30분, 40분, 50분) 강우자료가 누락될 경우 소규모 수공구조물 설계 시 원활한 배수를 위해 지점에 따라 기존의 여유율을 높일 필요가 있다.

• 지질공학
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• 제23권4호
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• pp.375-380
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• 2013

안전채수량 개념은 지하수 양수와 함양과의 균형에 초점을 맞춘 방법으로 자연적으로 배출되는 지하수 유출량에 대해서는 고려하지 못한다. 또한 하천과 연결된 충적대수층은 물공급과 수질면에서 상호 연결되어 있기에 별도로 이해하거나 관리할 수 없다. 따라서 미국 캔자스의 일부 지역에서는 기존의 안전채수량을 재평가하여 자연 지하수 배출량과 하천-대수층 상호작용을 고려한 수정된 안전채수량 개념을 제시하였고, 기저유량의 일정부분을 포함시키기 위해 최소하천유출량(MDS) 개념을 도입하였다. 본 연구에서는 수정된 안전채수량 개념을 우리나라에 맞게 적용하기 위해 하천유출과 연계한 개발가능량 산정방법을 제시하였다. 이를 위해 유출수문곡선으로부터 기저유출량을 분리하여 유황곡선으로 표시한 후, 결정된 최소하천유출량에 해당하는 양을 누적기저유출량에서 배제함으로써 개발가능량을 결정한다. 이 방법을 SWAT-K모형을 이용하여 통합모델링이 수행된 바 있는 무심천 유역에 대해 적용한 바, 연평균 개발가능량은 약 86 mm로 산정되었고, 각 소유역별로도 하천과 연계한 지하수 개발가능량을 구할 수 있었다.

• 한국습지학회지
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• 제15권4호
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• pp.585-593
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• 2013

본 연구는 강우 시 지표수의 관거 내 재유입을 고려할 수 있는 이중배수체계 모형을 활용하여 청주시의 설계 강우량에 따른 도시 유역의 침수를 모의하고 설계 강우량의 재현기간 변화에 따라 달라지는 침수특성을 분석하고자 한다. 이를 위해 청주시의 LiDAR 데이터로부터 $1m{\times}1m$ 해상도의 지표고도모델을 구축하여 입력 자료로 활용하였으며, 재현기간별 설계 강우량을 수문 입력 자료로 활용하였다. 분석 결과, 재현기간이 증가함에 따라 홍수량은 선형적인 증가를 보이지만, 침수면적은 재현기간 30년 이후 증가율이 완화되는 것으로 나타났으며, 평균 침수심의 경우 재현기간 30년 설계 강우량과 재현기간 200년 빈도 설계 강우량을 사용한 경우에 큰 폭의 증가가 발생했다. 한편 대상지역 내 주요 지점에 대한 통수부족량 산출 결과, 재현기간 10년의 설계 강우량을 활용한 경우에는 모두 통수 부족이 발생하지 않았으나 그 이상의 설계 강우량부터 통수부족이 발생하였다. 대상 지역 전체에 대한 통수 부족량 산출 결과, 재현기간 10년 이상의 설계 강우량부터 통수 부족량이 큰 폭으로 증가하나 설계 강우량의 재현기간이 50년을 넘어가면 통수 부족량의 증가율이 둔화되는 것으로 나타났다.

• 한국수자원학회논문집
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• 제45권11호
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• pp.1107-1119
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• 2012

본 연구의 목적은 도시하천으로 복원된 청계천유역의 실시간 홍수예보를 위한 flow nomograph를 개발하고, 실측자료를 통해 flow nomograph의 적용성을 검토하는데 있다. 본 연구의 적용대상 지역인 청계천 유역은 높은 불투수율, 짧은 도달시간 및 복잡한 수문학적 특성을 갖고 있어 기존 강우-유출 모형에 의한 홍수예측 방법의 선행시간 확보 측면에서 실효성을 거두지 못하고 있는 실정이다. 이에 본 연구에서는 홍수예보 선행시간을 확보하기 위해 강우정보만으로도 홍수예보가 가능한 flow nomograph를 개발하였다. Flow nomograph는 강우강도, 강우지속시간 등의 강우변수와 유량, 수위간의 상관관계를 구한 것이다. 본 연구에서는 Flow nomograph 개발과정에서 예보 기준 설정을 위해 홍수예보 지점을 선정하여 지점별 기준 홍수위를 산정하였으며, 다양한 홍수사상을 반영하기 위해 가상 강우시나리오를 설정하여 강우조건별 강우강도와 강우지속시간을 산정하였다. 또한 수위-유량관계 곡선식을 이용하여 기준 홍수위에 따라 홍수량 범위를 결정하고, SWMM모형을 이용하여 강우조건에 따른 지점별 홍수량을 산정하여 예보지점별로 기준홍수 위에 따른 홍수량을 산정하였다. 산정된 강우 시나리오에 따른 강우정보와 기준 홍수위에 따른 홍수량을 이용하여 flow nomograph를 개발하였으며, 이를 실제 홍수사상에 적용하여 평가하였다. 평가 결과 청계천 유역에 대해 flow nomograph의 적용성이 높은 것으로 나타났다. 향후 청계천과 같은 도시하천유역의 홍수예측 방법으로 활용도가 높을 것으로 판단된다.

• 미생물학회지
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• 제1권1호
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• pp.38-44
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• 1963

According to the experiment on pure-isolation and the related contaminants of Chlorella, the phenomena of the ecological distributions of Chlorella in Korea have been manifested in several areas and also the aim that in going to do culture, biological and physiological study of Chlorella is carried out. Contaminants very oftenly occupied on the colony of the strains taken in order to fulfil pure-isolation of Chlorella, but in accordance with being piled up the minute research on this subject, I can obtain the desirable results as follows: 1. For the pure-isolation, the duration chose the time from May to September 1957 so that may easily isolate from contaminant water with utilizing the antibiotic substances. 2. To take long time, 36-48 hours until growth of nascent through the non-sporulated, it originates from the difference of the cultured media. In addition to the above mention, the mechanism of growth until nascent through the sporulated must not always require the ligh. However the supply of metabolic energy depend upon its nutritional conditions per phase. 3. The culture of Chlorella should be based on the lower culturing except adding especial conditions such as reagent concentration of media, artifical shake of media and other facts due to the natural conditions. And also these strains grew not only in distilled water but 2% NaCl solution without any abnormality in cell it self. I, therefore, guess it is possible to culture in sea-water under phasic environment. 4. In the experiment of ammonia detection, it is caused by the sampling surroundings to contain the minute quantity of ammonia in strain No. M 918; that is the place to be plenty of Carbohydrate on behalf of protein. 5. To compare the absorption curve of chlorophyll of higher plant with that of Chlorella, the absorption zone made mostly the Same ones each other but a little absorption grade dose not clearly appear. The colony which formed giant type grows with intensive colour and green band on surrounding of the colony and after that it was changed into all the green colour and developed up to end. 6. At first phase for a week, the development of Chlorella suspends the normal condition as in vivo but after a few days, the colour of chlorophyll gradually changed into blue-yellow which secrete the mucous substances on the agar media. The cell was flew out the contained substances itself on leaving the cell wall only, or the various micro-organism diffused on the outer-region of the cell.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9301-9305
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• 2014

Background: Pain is one of the most terrifying symptoms for cancer patients. Although most patients with cancer pain need opioids, complete relief of pain is hard to achieve. This study investigated the factors influencing persistent pain-free survival (PPFS) and opioid efficiency. Materials and Methods: A prospective study was conducted on 100 patients with cancer pain, hospitalized at the medical oncology clinic of Akdeniz University. Patient records were collected including patient demographics, the disease, treatment characteristics, and details of opioid usage. Pain intensity was measured using a patient self-reported visual analogue scale (VAS). The area under the curve (AUC) reflecting the pain load was calculated from daily VAS tables. PPFS, the primary measure of opioid efficacy, was described as the duration for which a patient reported a greater than or equal to two-point decline in their VAS for pain. Predictors of opioid efficacy were analysed using a multivariate analysis. Results: In the multivariate analysis, PPFS was associated with the AUC for pain (Exp (B)=0.39 (0.23-0.67), P=0.001), the cumulative opioid dosage used during hospitalisation (Exp (B)=1.00(0.99-1.00), P=0.003) and changes in the opioid dosage (Exp (B)=1.01 (1.00-1.01), P=0.016). The change in VAS score over the standard dosage of opioids was strongly associated with current cancer treatment (chemotherapy vs. others) (${\beta}=-0.31$, T=-2.81, P=0.007) and the VAS for pain at the time of hospitalisation (${\beta}=-0.34$, T=-3.07, P= 0.003). Conclusions: The pain load, opioid dosage, concurrent usage of chemotherapy and initial pain intensity correlate with the benefit received from opioids in cancer patients.

• 콘크리트학회논문집
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• 제26권3호
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• pp.247-254
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• 2014

화재시 콘크리트 구조물은 구성재료의 상이한 열적특성으로 인해 강도가 저하하고 동시에 수직부재는 수평부재의 팽창에 의한 모멘트하중을 받아 전단파괴가 발생한다. 따라서 여러가지 화재곡선을 사용한 콘크리트 구조물의 화재시 거동에 대한 연구가 많이 이루어졌지만 주로 온도상승구간에서 발생하는 폭렬특성과 열팽창변형에 관한 연구가 대부분이다. 하지만 고온이 유지될 경우 발생할 수 있는 크리프변형은 화재시 구조물의 안정성에 큰 영향을 미치지만 상대적으로 연구가 미진한 상태이다. 또한 이러한 고온을 받는 콘크리트의 안정성에는 체적의 대부분을 차지하는 굵은골재의 열적특성이 큰 영향을 미치기 때문에 이 연구에서는 화강암계, clay계, clay-ash계 세 종류의 굵은골재를 사용한 콘크리트의 고온 역학적 특성을 평가했다. 그 결과 굵은골재의 성인으로 인한 내부공극 때문에 경량골재를 사용한 콘크리트가 일반골재를 사용한 콘크리트보다 높은 고온강도 및 탄성계수를 나타냈고 열팽창변형과 전체변형의 경우 더 낮은 변형률을 나타내어 온도상승구간에서의 구조적 안정성 측면에서 유리한 것으로 판단되었다. 그러나 고온크리프의 경우 내부공극으로 인해 더 큰 수축량이 발생하기 때문에 내화성능설계시에 이에 대한 추가적인 고려가 필요할 것으로 판단되었다.

• Journal of Preventive Medicine and Public Health
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• 제38권2호
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• pp.203-207
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• 2005

Objectives: Recently, the American Diabetes Association (ADA) redefined the criteria of prediabetes, which has lowered the diagnostic level of fasting plasma glucose (FPG) from 110 to 125 mg/dl, down to levels between 100 to 125mg/dl. The purpose of this study was to determine the predictive cutoff level of FPG as a risk for the development of diabetes mellitus in Korean men. Methods: A retrospective cohort study was conducted on 11,423 (64.5%) out of 17,696 males $\leq$30 years of age, and who met the FPG of $\leq$125 mg/dl and hemoglobin A1c of $\leq$ 6.4% criteria, without a history of diabetes, and who were enrolled at the screening center of a certain university hospital between January and December 1999. The subjects were followed from January 1999 to December 2002 (mean follow-up duration; 2.3(${\pm}0.7$) years). They were classified as normal (FPG <100mg/dl), high glucose (FPG $\geq$100mg/dl and <110mg/dl) and impaired fasting glucose (FPG $\geq$110mg/dl and $\leq$125mg/dl) on the basis of their fasting plasma glucose level measured in 1999. We compared the incidence of diabetes between the 3 groups by performing Cox proportional hazards model and used receiver operating characteristic analyses of the FPG level, in order to estimate the optimal cut-off values as predictors of incident diabetes. Results: At the baseline, most of the study subjects were in age in their 30s to 40s (mean age, 41.8(${\pm}7.1$) year). The incidence of diabetes mellitus in this study was 1.19 per 1,000 person-years (95% CI=0.68-1.79), which was much lower than the results of a community-based study that was 5.01 per 1,000 person-years. The relative risks of incident diabetes in the high glucose and impaired fasting glucose groups, compared with the normal glucose group, were 10.3 (95% CI=2.58-41.2) and 95.2 (95% CI= 29.3-309.1), respectively. After adjustment for age, body mass index, and log triglyceride, a FPG greater than 100mg/dl remained significant predictors of incident diabetes. Using the receiver operating characteristic (ROC) curve, the optimal cutoff level of FPG as a predictor of incident diabetes was 97.5 mg/dl, with a sensitivity and a specificity of 81.0% and 86.0%, respectively. Conclusion: These results suggest that lowering the criteria of impaired fasting glucose is needed in Korean male adults. Future studies on community-based populations, including women, will be required to determine the optimal cutoff level of FPG as a predictor of incident diabetes.

• Nutrition Research and Practice
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• 제14권1호
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• pp.20-24
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• 2020

BACKGROUND/OBJECTIVES: Malnutrition has multiple impacts on surgical success, postoperative complications, duration of hospital stay, and costs, particularly for cancer patients. There are various nutrition risk screening tools available for clinical use. Herein, we aim to determine the most appropriate nutritional risk screening system for esophageal cancer (EC) patients in China. SUBJECTS/METHODS: In total, 138 EC patients were enrolled in this study and evaluated by experienced nurses using three different nutritional screening tools, the Nutrition Risk Screening 2002 tool (NRS2002), the Patient-generated Subjective Globe Assessment (PG-SGA), and the Nutrition Risk Index (NRI).We compared sensitivity, specificity, positive and negative likelihood ratios, and Youden index generated by each of the three screening tools. Finally, cut-off points for all three tools were re-defined to optimize and validate the best nutritional risk screening tool for assessing EC patients. RESULTS: Our data suggested that all three screening tools were 100% sensitive for EC patients, while the specificities were 44.4%, 2.96%, and 59.26% for NRS 2002, PG-SGA, and NRI, respectively. NRI had a higher positive likelihood ratio as well as a higher area under the receiver operating characteristic curve compared to those of NRS 2002 and PG-SGA; although, all three tools had null negative likelihood ratios. After adjusting the cut-off points, the specificity and accuracy for all tools were significantly improved, however, the NRI remained the most appropriate nutritional risk screening system for EC patients. CONCLUSIONS: The NRI is the most suitable (highest sensitivity and accuracy) nutritional risk screening tool for EC patients. The performance of the NRI can be significantly improved if the cut-off point is modified according to the results obtained using MedCalc software.

• The Korean Journal of Pain
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• 제22권1호
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• pp.16-20
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• 2009

Background: Zaprinast is an inhibitor of phosphodiesterase 5, 6 and 9. Phosphodiesterase inhibitors could produce anti-nociceptive effects by promoting the accumulation of cGMP. We hypothesized that intrathecal zaprinast could attenuate the allodynia induced by chronic constriction injury of the sciatic nerve in rat. Methods: Sprague-Dawley rats were prepared with four loose ligations of the left sciatic nerve just proximal to the trifurcation into the sural, peroneal and tibial nerve branches. Tactile allodynia was measured by applying von Frey filaments to the lesioned hindpaw. The thresholds for the withdrawal responses were assessed. Zaprinast ($3-100{\mu}g$) was administered intrathecally by the direct lumbar puncture method to obtain the dose-response curve and the 50% effective dose ($ED_{50}$). Measurements were taken before and 15, 30, 45, 60, 90, 120, and 180 min after the intrathecal doses of zaprinast. The side effects were also observed. Results: Intrathecal zaprinast resulted in a dose-dependent antiallodynic effect. The maximal effects occurred within 15-30 min and then they gradually decreased down to the baseline level over time in all the groups. There was a dose dependent increase in the magnitude and duration of the effect. The $ED_{50}$ value was $17.4{\mu}g$ (95% confidence intervals; $14.7-20.5{\mu}g$). No severe motor weakness or sedation was observed in any of the rats. Conclusions: Intrathecally administered zaprinast produced a dose-dependent antiallodynic effect in the chronic constriction injury neuropathic pain model. These findings suggest that spinal phosphodiesterase 5, 6 and 9 may play an important role in the modulation of neuropathic pain.