• Bulletin of the Korean Chemical Society
• /
• v.24 no.8
• /
• pp.1207-1210
• /
• 2003

The effect of solvent structure on the slope in the plot of ln K vs. solute carbon number was examined. It was found that the free energy of methylene group transfer from the gas phase into a solvent was always negative and that the absolute magnitude of interaction free energy between the methylene group and the solvent was always larger than the absolute magnitude of cavity formation free energy of the methylene group in the solvent. Thus, the slope in the plot of ln K vs. solute carbon number was always positive and its value decreases with increase of solvent polarity since the cavity formation energy of the CH₂ unit increases with increase of solvent polarity while the dispersive interaction energy of the CH₂ unit is virtually invariant. We also examined the effect of sequential addition of CH₂ unit to a solvent molecule upon ln K for three homologous series of solvents: n-alkanes, n-alcohols, and n-nitriles. Characteristic trends in the plots of ln K vs. solvent carbon number were observed for individual solvent groups. A decrease of ln K with solvent carbon number was observed for n-alkanes. An abrupt increase in ln K followed by levelling off was observed for n-alcohols while a final slight decrease in ln K after an abrupt increase followed by rapid levelling off was noted for n-nitriles. All of theses phenomena were found related to variation in cavity formation energy. It was clearly shown that a structural change of a polar solvent by sequential addition of CH₂ units causes an abrupt polarity decrease initially, then gradual levelling off, and finally, conversion to a virtually nonpolar solvent if enough CH₂ units are added.

• Korean Journal of Remote Sensing
• /
• v.15 no.3
• /
• pp.195-208
• /
• 1999

In the classification of satellite images, the representative of training of classes is very important factor that affects the classification accuracy. Hence, in order to improve the classification accuracy, it is required to optimize pre-classification stage which determines classification parameters rather than to develop classifiers alone. In this study, the normality of training are calculated at the preclassification stage using SPOT XS and LANDSAT TM. A correlation coefficient of multivariate Q-Q plot with 5% significance level and a variance of initial training are considered as an object function of genetic algorithm in the training normalization process. As a result of normalization of training using the genetic algorithm, it was proved that, for the study area, the mean and variance of each class shifted to the population, and the result showed the possibility of prediction of the distribution of each class.

• Korean Journal of Radiology
• /
• v.22 no.4
• /
• pp.612-623
• /
• 2021

Objective: To evaluate the diagnostic performance of a deep learning algorithm for the automated detection of developmental dysplasia of the hip (DDH) on anteroposterior (AP) radiographs. Materials and Methods: Of 2601 hip AP radiographs, 5076 cropped unilateral hip joint images were used to construct a dataset that was further divided into training (80%), validation (10%), or test sets (10%). Three radiologists were asked to label the hip images as normal or DDH. To investigate the diagnostic performance of the deep learning algorithm, we calculated the receiver operating characteristics (ROC), precision-recall curve (PRC) plots, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) and compared them with the performance of radiologists with different levels of experience. Results: The area under the ROC plot generated by the deep learning algorithm and radiologists was 0.988 and 0.988-0.919, respectively. The area under the PRC plot generated by the deep learning algorithm and radiologists was 0.973 and 0.618-0.958, respectively. The sensitivity, specificity, PPV, and NPV of the proposed deep learning algorithm were 98.0, 98.1, 84.5, and 99.8%, respectively. There was no significant difference in the diagnosis of DDH by the algorithm and the radiologist with experience in pediatric radiology (p = 0.180). However, the proposed model showed higher sensitivity, specificity, and PPV, compared to the radiologist without experience in pediatric radiology (p < 0.001). Conclusion: The proposed deep learning algorithm provided an accurate diagnosis of DDH on hip radiographs, which was comparable to the diagnosis by an experienced radiologist.

• The Korean Journal of Pain
• /
• v.22 no.1
• /
• pp.39-46
• /
• 2009

Background: Ketamine has an indirect sympathetic stimulation effect. We investigated heart rate variability (HRV) as a marker of cardiac autonomic function after a target controlled infusion (TCI) of ketamine with a plasma concentration of 30 or 60 ng/ml. Methods: In 20 adult volunteers, the mean of the R wave to the adjacent R wave interval (RRI), the range of RRI, the root mean square successive difference of intervals (RMSSD), the total power, the low frequency (LF, 0.04-0.15 Hz) power, the high frequency (HF, 0.15-0.4 Hz) power, the normal unit HF (nuHF), the normal unit LF (nuLF), the LF/HF ratio and the SD1 and the SD2 in the Poincare plot were measured before and after a TCI of ketamine. We observed for any psychedelic symptoms or sedation. Results: There were no differences in the mean and range of the RRI, RMSSD, total power, LF power, HF power, nuHF, nuLF, LF/HF ratio, SD1 and SD2 between before and after ketamine administration. The OAA/S score was higher and there were more psychedelic symptoms with a 60 ng/ml plasma concentration than with a 30 ng/ml plasma concentration. Conclusions: This study did not show any effect of a low plasma concentration of ketamine on the autonomic nervous system.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.5
• /
• pp.2142-2147
• /
• 2012

This study is aimed at decreasing wrong diagnosis with corrected EF(Ejection Fraction) of 2D echo cardiography by analysing the physical time-resolution difference between Cine MRI and 2D echo cardiography and applying the corrected EF in 2D echocardiography. From February 2010 to December 2011, among the 110 patients who had undergone both 2D echo cardiography and cine MRI only 37 patient were selected suffering aortic valve regurgitation. ED, ES and SV were measured and EF was calculated in each system while normal ranges of Cine MRI and 2D echocardiography were compared to evauate misdiagnosis rate. The correlation of physical time resolution between 2D echocardiography and MRI was evaluated and the differences were corrected with linear regression coefficient which is derived from linear regression analysis. Blandt-Altman plot was used to evaluate the reliability of corrected 2D echo cardiography EF and compare the error among measured values. The values were compared with MRI normal range and misdiagnosis rate was measured again. As a result, misdiagnosis rates of physical time resolution were measured to be 32.4%(12people) before the correction of EF and 18.9%(7people) after the correction. Also, EF confirmed in Blandt-Altman plot were almost the same with MRI EF. In conclusion, when diagnosing aortic regurgitation disease, simply using 2D echocardiography can easily raise the misdiagnosis rates, therefore considering the MRI machine's physical merits, correcting the time resolution difference is important by calculating time resolution wrong diagnosis would decrease and it is considered to be useful in clinical circumstances.

• Journal of Mushroom
• /
• v.11 no.3
• /
• pp.131-136
• /
• 2013

The effects of fixed and variable relative humidity on fruiting body formation and characters of Pleurotus eryngii were investigated with normal and thinning treatment plots. In fixed relative humidity, as humidity was lower, period of harvest was longer as well as days for pinheading in the both of normal and thinning plots. In the normal plot, qualities of mushroom were 5.5, 5.8, and 6.3 and yield was 98.6 g per bottle for 90% relative humidity, it was best. In the thinning plot, qualities of mushroom were 7.7, 8.4, and 8.5 and yields were 102.1, 105.8, and 116.9 g at 70, 80, and 90% respectively. In variable relative humidity with a thinning plot, the yield of P. eryngii on condition I(>90% for 1 day ${\rightarrow}$ 85% until thinning(for about 11 days) ${\rightarrow}$ 80%) and III(>90% until pin-heading(about for a week) ${\rightarrow}$ 85% until thinning(about for 5 days) ${\rightarrow}$ 80%) were 85.5 and 87.8 g per bottle, and qualities were 7.8 and 8.0 respectively. For long shelf life and a cultural control of bacterial soft rot disease, the condition I will be more largely adopted by mushroom farmers.

• The Korean Journal of Physiology
• /
• v.9 no.1
• /
• pp.33-37
• /
• 1975

Adult rabbits were anesthetized with nembutal, 30 mg/kg. Carotid artery and jugular vein were exposed surgically and cannulated with polyethylene tubing. Arterial blood pressure was recorded via pressure transducer on the physiograph and $100{\mu}g/ml$ of histamine solution was infused through the jugular vein by using the constant infusion pump with a rate of 0.92 ml/min or 1.40 ml/min. Mean arterial blood pressure was maintained at $40{\sim}70 mmHg$ and hypotension was kept for 2 hours. After the termination of this period, blood was taken and osmotic fragility was mea sured immediately. Also, every sample of normal blood and shocked blood was incubated for 1 hour or 2 hours at $37^{\circ}C$ in order to see whether or not there was some influence of incubation. Furthermore to clarify which component was responsible for the change on the fragility, the mixtures of normal blood cells with shocked plasma and shocked blood cells with normal plasma were also incubated at $37^{\circ}C$ for one or two hours and fragility in such cases was measured. The data obtained were analysed by probit-plot method and the concentration of saline solution at which the hemolysis started to occur, 50% of blood cells were hemolysed and that at which the red blood cells hemolysed completely were determined. The values for the blood of hypotension stage were compared with those of the control blood. The results obtained were as fellows: 1. Osmotic fragility of red blood cell was increased in hypotensive state induced by histamine. 2. The differences of osmotic fragility after two hours of incubation were negligible both in normal blood and in that of hypotensive state. 3. Osmotic resistance of normal red blood cell incubated in shock plasma was less than that of shock red blood cell incubated in normal plasma. It was suggested that plasma in hypotensive state caused by histamine might be primarily responsible for the alteration of red blood cell fragility.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.21
• /
• pp.9453-9458
• /
• 2014

Background: Breast cancer is the second leading cause of cancer death for women in the United States. Differences in survival of breast cancer have been noted among racial and ethnic groups, but the reasons for these disparities remain unclear. This study presents the characteristics and the survival curve of two racial and ethnic groups and evaluates the effects of race on survival times by measuring the lifetime data-based half-normal model. Materials and Methods: The distributions among racial and ethnic groups are compared using female breast cancer patients from nine states in the country all taken from the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry. The main end points observed are: age at diagnosis, survival time in months, and marital status. The right skewed half-normal statistical probability model is used to show the differences in the survival times between black Hispanic (BH) and black non-Hispanic (BNH) female breast cancer patients. The Kaplan-Meier and Cox proportional hazard ratio are used to estimate and compare the relative risk of death in two minority groups, BH and BNH. Results: A probability random sample method was used to select representative samples from BNH and BH female breast cancer patients, who were diagnosed during the years of 1973-2009 in the United States. The sample contained 1,000 BNH and 298 BH female breast cancer patients. The median age at diagnosis was 57.75 years among BNH and 54.11 years among BH. The results of the half-normal model showed that the survival times formed positive skewed models with higher variability in BNH compared with BH. The Kaplan-Meir estimate was used to plot the survival curves for cancer patients; this test was positively skewed. The Kaplan-Meier and Cox proportional hazard ratio for survival analysis showed that BNH had a significantly longer survival time as compared to BH which is consistent with the results of the half-normal model. Conclusions: The findings with the proposed model strategy will assist in the healthcare field to measure future outcomes for BH and BNH, given their past history and conditions. These findings may provide an enhanced and improved outlook for the diagnosis and treatment of breast cancer patients in the United States.

• Korean Journal of Soil Science and Fertilizer
• /
• v.18 no.2
• /
• pp.201-207
• /
• 1985

The experiments were conducted in order to evaluate the effect of a compound fertilizer for application of potato plants (Sumi) which were prepared by the Kyonggj Chemical LTD. The results were summarized as follows; 1. Comparing with the plot of 12kg/10a muriate of potash plot, the potato yield of compound fertilizer, double rate of potassium sulfate and normal rate of potassium sulfate plots were increased in order to 44%, 7% and 6% respectively. The yield of potato at the compound fertilizer were significantly higher than that of double rate of potassium sulfate, but the latter yield was lower that of control. 2. The yield of potato were to exeeding of final tuber on June 25, which was twelve day earlier than the actual harvest the application of the compound fertilizer may make possible to harvest potato eariler than normal season and benefit fammers which better economic return. 3. Manufacturing it with granular form at diammonium phosphate, ammonium sulfate and potassium sulfate as majour source materials and having little urea contents, the compound fertilizer raised higher the emergence rate of potato plant than the other fertilizer were promoted the early plant growth, and kept potato plants comparatively healthier than the other fertilizer even at later stage of plant growth.

• Journal of Mushroom
• /
• v.10 no.4
• /
• pp.160-166
• /
• 2012

The effects of fixed and variable temperatures on fruiting body formation and characters of mushrooms were investigated with normal and thinning treatment plots. In fixed temperature, as temperature was lower, period of harvest was longer as well as days for pinheading in the both of normal and thinning plots. Harvest rate were 91.0, 90.3, and 95.8% at $13^{\circ}C$, $17^{\circ}C$, and $15^{\circ}C$. In the thinning plot, qualities of mushrooms were 7.5, 8.1, and 7.7, and yields were 86.0, 105.9, 104.0g at 13, 15, and $17^{\circ}C$ respectively. In variable temperature with a variable temperature plot, condition II($17^{\circ}C$ for pin-heading(before reverting, 7-8 days)${\rightarrow}16^{\circ}C$ for extending primodia(before thinning, 4-5 days)${\rightarrow}15^{\circ}C$ for extending (after thinning)) was the best for yield which was better than other conditions by 17.4% and 4.0% and quality of mushroom was highest 8.1 among all conditions.