• 대기
• /
• 제24권1호
• /
• pp.17-27
• /
• 2014

In this study, the observational environment for sunshine duration at Seoul and Daegu Automated Synoptic Observing Systems (ASOSs) was analyzed using a numerical model. In order to analyze the effects of topography and buildings on observational environment for sunshine duration, the model domains including the elevated building and mountainous areas around Seoul and Daegu ASOSs were considered. Three dimensional topography and buildings used as input data for the numerical model were constructed using a geographic information system (GIS) data. Solar azimuth and altitude angles calculated for the analysis period (one-week for each season in 2008) in this study were validated against those by Korea Astronomy and Space Science Institute (KASI). The starting and ending times of sunshine duration observed at ASOSs largely differed from the respective sunrise and sunset times simply calculated using solar angles and information of ASOSs' latitude and longitude, because uneven topography and elevated buildings around ASOSs cut off sunshine duration right after the sunrise and right before the sunset. The model produced the sunshine indices for Seoul and Daegu ASOSs with the time interval of one minute and the period of one week for each season and we compared the hourly averaged indices with those observed at the ASOSs. One week of which the cloudiness is lowest for each season is selected for analysis. Not only the adjacent buildings but also distant buildings and mountain cut off sunshine duration right after the sunrise and right before the sunset. The buildings and topography cutting off sunshine duration were found for each analyzing date. It was suggested that, in order to evaluate the observational environment for sunshine duration, we need to consider even the information of topography and/or building far away from ASOSs. This study also showed that the analyzing method considering the GIS data is very useful for evaluation of observational environment for sunshine duration.

• 한국초지조사료학회지
• /
• 제11권2호
• /
• pp.121-128
• /
• 1991

샤일리지용 수수와 청예용 수수-수만그라스 교잡 종의 사료생산에 안맞은 수확기를 안기 위하여 수수 2품종(p 931, P 956)과 수수 수단그라스 교잡종 1 품종(P 988)을 재배하여, 수수는 출수기부터 1주일 간격으로 6회 수확하였고 재생한 것은 10월 13일에 모두 수확하였다 수수-수단그라스는 출수 1주전부 터 1주후까지 6회 수확하였고, 재생한 것은 2차 혹은 3차 수확하여 수화시기가 사료의 생산성과 사료가치에 미치는 영향을 조사한 결과는 다음과 같다 1. 수수의 1차 수확과 수수-수단그라스 1,2차 수확의 건물비율은 수확기가 늦을수록 증가하였으나 수수의 2차 수확은 생육기간이 충분하지 않아 1차 수화가가 빠를수록 건물비율이 높았다. 2. 1자 수확에서 수수는 수확기가 늦을수록 잎몸과 줄기+옆집의 구성비율은 감소하나 이삭비율은 증가 하였고 수수 P 956이 P 931 보다 이삭비율의 증가율은 컸으나 줄기+잎집 비율은 감소하였다 그러나 수수-수단그라스는 수획기가 늦을수록 잎몸비율은 감소하고 줄기+잎집 비율은 증가하였다 3 .수수의 l차 수확에서는 수확기가 늦을수록 조단백질, 조섬유 함량은 감소하였고, 가용성 무질소물 은 증가하였으며, 조지방과 조회분은 비슷하였다. 그러나 2차 수확은 1차 수확기가 빠를수록 조단백질과 조회분 함량은 다소 감소하였고, 가용성 무질소물은 증가하였으며, 조지방, 조섬유 함량은 비슷하였다. 수수-수단그라스는 수확기가 늦을수록 1차 수확의 조단백질은 감소하였고, 1차 수확의 조섬유와 1,2차 수확의 가용성 무질소물은 증가하였으며, 나머지는 수확기간에 차이가 없었다. 4 수수의 1차 수확에서는 출수기에서 출수 3주 후까지 건물수량이 증가하였으나 재생수량을 합한 총 건물수량은 수확기간에 차이가 없었다 수수-수단그라스는 수확가가 늦을수록 1차 수확과 1, 2, 3차 수확을 합한 총 건물수량이 증가하였다.

• Physical Therapy Rehabilitation Science
• /
• 제7권3호
• /
• pp.102-108
• /
• 2018

Objective: To investigate whether the Minimal Clinically Important Difference (MCID) clinically defines improvement of Berg Balance Scale (BBS) scores in people with acute stroke in response to rehabilitation. Design: Retrospective study. Methods: Seventy-three participants with acute stroke participated in the study. Balance evaluation was performed using the BBS. All patients received rehabilitation with physical therapy for 4 weeks, 5 times a week, for 2 hours and 20 minutes a day. An anchor-based approach using the clinical global impression was used to determine the MCID of the BBS. The MCID was used to define the minimum change in the BBS total score (postintervention-preintervention) that was needed to perceive at least a 3-point improvement on the global rating of change. Receiver operating characteristic (ROC) curves was used to define the cut-off values of the optimal MCID of the BBS in order to discriminate between improvement and no improvement groups. Results: The optimal MCID cut-off point for the BBS change scores was 12.5 points for males with a sensitivity (Sn) of 0.62 and a specificity (Sp) of 0.89, and 12.5 points for females with a Sn of 0.69 and Sp of 0.85. The area under the curve of the ROC curve for all participants were 0.84 (95% confidence interval [CI], 0.72; 0.95, p<0.001), and 0.89 (95% CI, 0.77; 1.00, p<0.001), respectively. Conclusions: The MCID for improvement in balance as measured by the BBS was 13.5 points, indicating that the MCID does clinically detect changes in balance abilities in persons with stroke.

• The Korean Journal of Pain
• /
• 제33권1호
• /
• pp.54-59
• /
• 2020

Background: The median nerve cross-sectional area (MNCSA) is a useful morphological parameter for the evaluation of carpal tunnel syndrome (CTS). However, there have been limited studies investigating the anatomical basis of median nerve flattening. Thus, to evaluate the connection between median nerve flattening and CTS, we carried out a measurement of the median nerve thickness (MNT). Methods: Both MNCSA and MNT measurement tools were collected from 20 patients with CTS, and from 20 control individuals who underwent carpal tunnel magnetic resonance imaging (CTMRI). We measured the MNCSA and MNT at the level of the hook of hamate on CTMRI. The MNCSA was measured on the transverse angled sections through the whole area. The MNT was measured based on the most compressed MNT. Results: The mean MNCSA was 9.01 ± 1.94 ㎟ in the control group and 6.58 ± 1.75 ㎟ in the CTS group. The mean MNT was 2.18 ± 0.39 mm in the control group and 1.43 ± 0.28 mm in the CTS group. Receiver operating characteristics curve analysis demonstrated that the optimal cut-off value for the MNCSA was 7.72 ㎟, with 75.0% sensitivity, 75.0% specificity, and an area under the curve (AUC) of 0.82 (95% confidence interval [CI], 0.69-0.95). The best cut off-threshold of the MNT was 1.76 mm, with 85% sensitivity, 85% specificity, and an AUC of 0.94 (95% CI, 0.87-1.00). Conclusions: Even though both MNCSA and MNT were significantly associated with CTS, MNT was identified as a more suitable measurement parameter.

• Physical Therapy Rehabilitation Science
• /
• 제7권2호
• /
• pp.54-60
• /
• 2018

Objective: Persons with chronic stroke fall more often than healthy elderly individuals. The Timed Up and Go test (TUG) is used as a fall prediction tool, but only provides a result for the total measurement time. This study aimed to determine the optimal cut-off values for each of the 6 components of the TUG. Design: Retrospective study. Methods: Thirty persons with chronic stroke participated in the study. TUG evaluation was performed using a wearable miniaturized inertial sensor. Sensitivity, specificity, and predictive values were calculated using the Receiver Operating Characteristic (ROC) curve analysis for the measured values in each section. Optimal values for fall risk classification were determined. Logistic regression analysis was used to investigate the risk of future falls based on TUG. Results: The cut-off values of the 6 sections of the TUG were determined, as follows: sit-to-stand >2.00 seconds (p<0.05), forward gait >4.68 seconds (p<0.05), mid-turn >3.82 seconds (p<0.05), return gait >4.81 seconds (p<0.05), end-turn >2.95 seconds (p<0.05), and stand-to-sit >2.13 seconds (p<0.05). The risk of falling increased by 2.278 times when the mid-turn value was >3.82 seconds (p<0.05). Conclusions: The risk of falls increased by 2.28 times when the value of the mid-turn interval exceeded 3.82 seconds. Therefore, when interpreting TUG results, the predictive accuracy for falls will be higher when the measurement time for each section is analyzed, together with the total time for TUG.

• 중환자간호학회지
• /
• 제15권3호
• /
• pp.75-87
• /
• 2022

Purpose : This retrospective investigation study aimed to determine the predictive validity of superficial surgical site infection assessment tools by measuring the risk score at the surgical site. Methods : This study included patients hospitalized to the general surgery department of a Hospital from January 2021 to December 31, 2021. The inclusion criteria were age ≥19 years, general abdominal surgery under general anesthesia, and hospital stay longer than 2 days. Patients who had undergone transplantation were excluded. Results : Tool validity results showed that tools including surgical time and operative procedure were more accurate than previously developed tools, with a sensitivity of 71.1%, specificity of 71.4%, positive prediction of 12.3%, negative prediction of 97.8%, and area under the curve of 0.743 (95% confidence interval, 0.678~0.745). The tool's cut-off score was 15, and the risks of infection was increased by 6.14 times at or above this cut-off point. Preoperative hair removal period, surgical wound classification, surgery time, body temperature on the second day after surgery, drainage tube type, and suture type affected the risk of infection at the surgical site. Conclusion : The incidence of healthcare-associated infections has been declining in the past decade; however, surgical site infections still account for a considerable proportion. Therefore, early identification of high-risk groups for surgical site infection is crucial for reducing the incidence of surgical site infection using appropriate management.

• The Korean Journal of Pain
• /
• 제36권1호
• /
• pp.84-97
• /
• 2023

Background: The concept of high-impact chronic pain (HICP) has been proposed for patients with chronic pain who have significant limitations in work, social life, and personal care. Recognition of HICP and being able to distinguish patients with HICP from other chronic pain patients who do not have life interference allows the necessary measures to be taken in order to restore the physical and emotional functioning of the affected persons. The aim was to reveal the risk factors and predictors associated with HICP. Methods: Patients with chronic pain without life interference (grade 1 and 2) and patients with HICP were compared. Significant data were evaluated with regression analysis to reveal the associated risk factors. Receiving operating characteristic (ROC) analysis was used to evaluate predictors and present cutoff scores. Results: One thousand and six patients completed the study. From pain related cognitive processes, fear of pain (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.87-0.98; P = 0.007) and helplessness (OR, 1.06; 95% CI, 1.01-1.12; P = 0.018) were found to be risk factors associated with HICP. Predictors of HICP were evaluated by ROC analysis. The highest discrimination value was found for pain intensity (cut-off score > 6.5; 83.8% sensitive; 68.7% specific; area under the curve = 0.823; P < 0.001). Conclusions: This is the first study in our geography to evaluate HICP with measurement tools that evaluate all dimensions of pain. Moreover, it is the first study in the literature to evaluate predictors and cut-off scores using ROC analysis for HICP.

• Journal of Chest Surgery
• /
• 제56권2호
• /
• pp.99-107
• /
• 2023

Background: The neutrophil-to-lymphocyte ratio (NLR) has been suggested as a novel predictive marker of cardiovascular disease. However, its prognostic role in patients under-going coronary artery bypass grafting (CABG) is unclear. This study aimed to determine the association between the preoperative NLR and early mortality in patients undergoing CABG. Methods: Cardiac surgery was performed in 2,504 patients at Seoul St. Mary's Hospital from January 2010 to December 2021. This study retrospectively reviewed 920 patients who underwent isolated CABG, excluding those for whom the preoperative NLR was unavailable. The primary endpoints were the 30- and 90-day mortality after isolated CABG. Risk factor analysis was performed using logistic regression analysis. Based on the optimal cut-off value of preoperative NLR on the receiver operating characteristic curve, high and low NLR groups were compared. Results: The 30- and 90-day mortality rates were 3.8% (n=35) and 7.0% (n=64), respectively. In the multivariable analysis, preoperative NLR was significantly associated with 30-day mortality (odds ratio [OR], 1.28; 95% confidence interval [CI], 1.17-1.39; p<0.001) and 90-day mortality (OR, 1.17; 95% CI, 1.07-1.28; p<0.001). The optimal cut-off value of the preoperative NLR was 3.4. Compared to the low NLR group (<3.4), the high NLR group (≥3.4) showed higher 30- and 90-day mortality rates (1.4% vs. 12.1%, p<0.001; 2.8% vs. 21.3%, p<0.001, respectively). Conclusion: Preoperative NLR was strongly associated with early mortality after isolated CABG, especially in patients with a high preoperative NLR (≥3.4). Further studies with larger cohorts are necessary to validate these results.

• 한국음향학회:학술대회논문집
• /
• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
• /
• pp.963-970
• /
• 1994

In speech signal processing, it is very important to detect the pitch exactly. The algorithms for pitch extraction that have been proposed until now are not enough to detect the fine pitch in speech signal. Thus we propose the new algorithm which takes advantage of the G-peak extraction. It is the method to find MZCI(maximum zer-crossing interval) which is defined as cut-off bandwidth rate of LPF (low pass filter)and detect the pitch period of the voiced signals. This algorithm performs robustly with a gross error rate of 3.63% even in 0 dB SNR environment. The gross error rate for clean speech is only 0.18%. Also it is able to process all course with speed.

• 응용통계연구
• /
• 제25권6호
• /
• pp.1027-1036
• /
• 2012

Among various biometrics recognition systems, statistical fingerprint recognition matching methods are considered using minutiae on fingerprints. We define similarity distance measures based on the coordinate and angle of the minutiae, and suggest a fingerprint recognition model following statistical distributions. We could obtain confidence intervals of similarity distance for the same and different persons, and optimal thresholds to minimize two kinds of error rates for distance distributions. It is found that the two confidence intervals of the same and different persons are not overlapped and that the optimal threshold locates between two confidence intervals. Hence an alternative statistical matching method can be suggested by using nonoverlapped confidence intervals and optimal thresholds obtained from the distributions of similarity distances.