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Comparison of Center Error or X-ray Field and Light Field Size of Diagnostic Digital X-ray Unit according to the Hospital Grade (병원 등급에 따른 X선조사야와 광조사야 간의 면적 및 중심점 오차 비교)

  • Lee, Won-Jeong;Song, Gyu-Ri;Shin, Hyun-yi
    • Journal of the Korean Society of Radiology
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    • v.14 no.3
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    • pp.245-252
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    • 2020
  • The purpose of this study was intended to recognize the importance of quality control (QC) in order to reduce exposure and improve image quality by comparing the center-point (CP) of according to hospital grade and the difference between X-ray field (XF) and light field (LF) in diagnostic digital X-ray devices. XF and LF size, CP were measured in 12 digital X-ray devices at 10 hospitals located in 00 metropolitan cities. Phantom was made in different width respectively, using 0.8 mm wire after attaching to the standardized graph paper on transparent plastic plate and marked as cross wire in the center of the phantom. After placing the phantom on the table of the digital X-ray device, the images were obtained by shooting it vertically each field of survey. All images were acquired under the same conditions of exposure at distance of 100cm between the focus-detector. XF and LF size, CP error were measured using the picture archiving communication system. data were expressed as mean with standard error and then analyzed using SPSS ver. 22.0. The difference in field between the XF and LF size was the smallest in clinic, followed by university hospitals, hospitals and general hospitals. Based on the university hospitals with the least CP error, there was a statistically significant difference in CP error between university hospitals and clinics (p=0.024). Group less than 36-month after QC had fewer statistical errors than 36-month group (0.26 vs. 0.88, p=0.036). The difference between the XF and LF size was the lowest in clinic and CP error was the lowest in university hospital. Moreover, hospitals with short period of time after QC have fewer CP error and it means that introduction of timely QC according to the QC items is essential.

INVESTIGATION OF THE EFFECT OF AN ANTIBIOTIC "P" ON POTATOES ("감자에 대한 항생제(抗生劑) 피마리신의 통계적(統計的) 효과(效果) 분석(分析)")

  • Kim, Jong-Hoon
    • Journal of Korean Society for Quality Management
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    • v.5 no.2
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    • pp.59-120
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    • 1977
  • An antibiotic 'P', which is one of the products of the Gist Brocades N. V. is being tested by its research department as fungicide on seed-potatoes. For this testing they designed experiments, with two control groups, one competitor's product, eight formulations of the antibiotic to be tested in different concentrations and one mercury treatment which can not be used in practice. The treated potatoes were planted in three different regions, where bifferent conditions prevail. After several months the harvested potatoes are divided in groups according to their diameter, potato illness is analysed and counted. These data were summarised in percentage and given to us for Analysis. We approached and analysed the data by following methods: a. Computation of the mean and standard deviation of the percenage of good results in each size group and treatment. b. Computation of the experimental errors by substraction of each treatment mean from observed data. c. Description of the frequency table, plotting of a histogram and a normal curve on same graph to check normality. d. Test of normality paper and chi-sqeare test to check the goodness of fit to a normal curve. e. Test for homogeneity of variance in each treatment with the Cochran's test and Hartley's test. f. Analysis of Variance for testing the means by one way classifications. g. Drawing of graphs with upper and lower confidence limits to show the effect of different treatments. h. T-test and F-test to two Control mean and variance for making one control of Dunnett's test. i. Dunnett's Test and calculations for numerical comarision of different treatments wth one control. In region R, where the potatoes were planted, it was this year very dry and rather bad conditions to grow potatoes prevailed during the experimental period. The results of this investigation show us that treatment No.2, 3 and 4 are significantly different from other treatments and control groups (none treated, just like natural state). Treatment no.2 is the useless mercury formulation. So only No. 3 and 4, which have high concentrations of antibiotic 'P', gave a good effect to the potatoes. As well as the competitors product, middle and low concentrated formulations are not significantly different from control gro-ups of every size. In region w, where the potatoes got the same treatments as in region R, prevailed better weather conditions and was enough water obtainable from the lake. The results in this region showed that treatment No. 2, 3, 4, and 5 are Significantly different from other treatments and the control groups. Again No.2 is the mercury treatmentin this investigation. Not only high concentrated formulation of antibiotic 'P', but also the competitor's poroduct gave good results. But, the effect of 'P', was better than the competitors porduct. In region G, where the potatoes got the same treatments as in the regions R and w. and the climate conditions were equal to region R, the results showed that most of the treatments are not significantly different from the control groups. Only treatment no. 3 was a little bit different from the others. but not Significantly different. It seems to us that the difference between the results in the three regions was caused by certain conditions like, the nature of the soil the degres of moisture and hours of sunshine, but we are not sure of that. As a conclusion, we can say that antibiotic 'P' has a good effect on potatoes, but in most investigations a rather high concentration of 'P' was required in formulations.

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Biomechanical and Physiological Comparative Analysis of the Single-Radius Knee Arthroplasty Systems and Multi-Radius Knee Arthroplasty Systems (무릎인공관절 단축범위(Single-Radius) 수술자와 다축범위(Multi-Radius) 수술자의 운동역 학적 및 운동생리학적 비교분석)

  • Jin, Young-Wan;Kwak, Yi-Sub
    • Journal of Life Science
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    • v.18 no.11
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    • pp.1532-1537
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    • 2008
  • The purpose of this study was to investigate the effect of different arthroplasty designs on knee kinematic and lower limb muscular activation for up-stair and down-stair movement. 3-D video analysis of whole body and joint kinematics and EMG analysis of quadriceps and hamstrings were conducted. One-way ANOVAs were used for statistical analyses (p=0.05). The single-radius group exhibited more arthroplasty limb quadriceps EMG and hamstring coactivation EMG than the multi-radius group. Single-radius demonstrated more abduction angular displacement and reached peak abduction earlier than the multi-radius arthroplasty limb. The single- radius the percent body fat showed similar values in the Elderly, Single and Multi-radius group among the periods, however Control group was Lowered among the periods. Single-radius group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. Resting metabolic rate was significantly increased in control group in the period of LI. Energy expenditure was extremely increased in all groups except control group among the periods. We can say this is the exercise effects.

Studies on the Vegetation around the Industrial Complexes (사대공단(四大工團) 주변(周邊)의 식생(植生)에 대(對)한 연구(硏究))

  • Kim, Tae Wook;Kim, Su In
    • Journal of Korean Society of Forest Science
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    • v.57 no.1
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    • pp.8-13
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    • 1982
  • The present study was conducted during the period July 18-August 11, 1981, at the four industrial complexes(Pohang, Ulsan, Onsan, and Yeochon) using the naked eye method. The study included the survey of plant species growing within a 2km from the area of pollution source, selection of plants tolerant to air pollution and effects of pollution on their growth. The results obtained are as follows; 1) Vascular plants surveyed as to industrial complexes consist of 90 families, 6 subfamilies, 213 genera and 290 species. Major plant families and species for each area are as follows: 1) Pohang area: 54 families, 102 genera and 126 species Leguminosae(16) Graminae(11), Compositae(9) Rosaceae(9) 2) Ulsan area: 61 families, 131 genera, and 158 species Compositae(17) Gramineae(16) Leguminosae(15) Rosaceae(9) Polygonaceae(9) Solanaceae(6) 3) Onsan area: 46 families, 98 genera, and 158 species Compositae(12) Gramineae(12) Leguminosae(12) Rosaceae(6) Polygonaceae(6) 4) Yeochon: 71 families, 150 genera, and 188 species Rosaceae(15) Leguminosae(15) Compositae(14) Graminese(14) Polygonaceae(8) Salicaceae(6) 2. Table 1 shows tolerant plants to air pollution in this study. 3. The following plants may be recommended as planting species at the industrial complex area. Leguminosae: Amorpha fruticosa L. Lespedeza bicolor Turcz. Lespedeza maximowiczii Schneider Robinia pseudoacacia L. Sophora japonica L. Fagaceae: Quercus acutissima Carr. Quercus serrata Thunb. Quercus variabilis Bl. Salicaceae: Populus tomentiglandulosa T. Lee Salix Pseudo-lasiogyne Leveille Oleaceae: Ligustrum japonicum Thunb. Ligustrum obtusifolumn S. et Z. Betulaceae: Alnus hirsuta (Space) Ruprecht Celastraceae: Euonymus japonicus thunb. Cparifolicceae: Viburnum awabucki K. Koch. Pinaceae: Cedrus deodara Loundon.

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A study of Digestion and Absorption Rates of Nutients in Korean Diets on Human Subjects (한국식이(韓國食餌)의 소화흡수(消化吸收)에 대(對)한 연구(硏究))

  • Ju, Jin-Soon;Hwang, Woo-Ik;Rim, Keun-Choll
    • Journal of Nutrition and Health
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    • v.1 no.2
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    • pp.61-85
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    • 1968
  • The experiment was carried out on eight healthy male subjects of 19-22 years old and they were maintained The experiment was carried out on eight healthy male subjects of 19-22 years old and they were maintained under the rice diet, the general mixed diet and the high animal protein diet for 7 days of each experimental period, respectively. The composition of each diet was indicated in Table 3. The allowance' of each nutrient per head per day in each diet were as follows. a) In the rice diet; protein:139.5 g (animal source:64.6 g, vegetable source:74.9 g), fat:25.3 g (animal source:11.3 g, vegetable source:14.0 g), carbohydrate: 644.0 g, calcium:982.3 mg, phosphorus: 2369.2mg, thiamine:2.1 mg, riboflavin: 1.6 mg, and 3211 Cal. b) In the general mixed diet; protein: 97.4g (animal source: 10.5 g, vegetable source: 86.9 g), fat:40.3 g (animal source:7.1 g, vegetable source:33.2 g), carbohydrate:620.7 g, calcium:887.1m g, phosphorus:2200.8m g, thiamine: 1.8m g, riboflavin:1.9m g, and 3158 Cal. c) In the high animal protein diet; protein: 135.6 g (animal source:68.8 g, vegetable source:66.8 g), fat:32.5g (animal source:17.9 g, vegetable source:14.6 g), carbohydrate:930.9 g, calcium: 626.0 mg, phosphorus: 1998.9 mg, thiamine: 1.5 mg, riboflavin: 1.5 mg, and 3194 Cal. The absorption rates of protein, fat, carbohydrate, calcium, phospherus, thiamine and riboflavin in each diet were observed. The results obtained were summarized as follows: 1. The absorption rates of protein and fat in the rice diet were 88.t % and 71.3.%. 2. The absorption rates of protein and fat in the general mixed diet were 83.4% and 86.4%. 3. The absorption rates of protein and fat in the high animal protein diet were 86.8% and 82.4%. 4. The nitrogen balances in the rice, the general mixed and the high animal protein diet groups were +5.7g, +2.3g and +4.0g respectively. 5. The absorption rates of carbohydrate in each diet were all above 95 % and so seemed to be almost completely absorbed except the cellulose in the diets. 6. The calory utilization rates in each diet were all above 93 %. 7. The minimum absorption rates of protein, fat and calory were 83.8%, 63.3%, and 89.7% in the rice diet, 80.0%, 80.9% and 85.9%, in the general mixed diet and 83.6%, 75.7% and. 89.3 % in the high animal protein diet respectively. Therefore, it is assumed that these data might be significant in practical use. 8. The protein absorption rates of the rice diet (88.1 %) was better than that of the general mixed diet (83.4 %). 9. The fat absorption rates of the general mixed diet and the high animal protein diet (86.4% and 82.4%) were signficantly better than that of the rice diet (71.3%). 10. The calcium absorption rates of each diet, rice diet, the general mixed diet and the high animal protein diet were 41.6%, 36.0%, and 27.7%, respectively. 11. The phosphorus absorption rates of each diet were 51.4%, 56.0% and 52.3%, respectively.12. The phosphorus absorption rate seemed better than that of calcium. 13. The thiamine absorption rates of each diet seemed 27.0 %, 42.9 % and 29.5 %, respectively. 14. The riboflavin absorption rates of each diet seemed above 30.6%, 27.1%, and 39.3% respectively. 15. The excretion amounts of thiamine or riboflavin were much more than the amounts ingested of the both vitamins. Therefore, the certain amount of both vitamins seemed to synthesize in the intestine.

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A Study on the Development of a Simulation Model for Predicting Soil Moisture Content and Scheduling Irrigation (토양수분함량 예측 및 계획관개 모의 모형 개발에 관한 연구(I))

  • 김철회;고재군
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.19 no.1
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    • pp.4279-4295
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    • 1977
  • Two types of model were established in order to product the soil moisture content by which information on irrigation could be obtained. Model-I was to represent the soil moisture depletion and was established based on the concept of water balance in a given soil profile. Model-II was a mathematical model derived from the analysis of soil moisture variation curves which were drawn from the observed data. In establishing the Model-I, the method and procedure to estimate parameters for the determination of the variables such as evapotranspirations, effective rainfalls, and drainage amounts were discussed. Empirical equations representing soil moisture variation curves were derived from the observed data as the Model-II. The procedure for forecasting timing and amounts of irrigation under the given soil moisture content was discussed. The established models were checked by comparing the observed data with those predicted by the model. Obtained results are summarized as follows: 1. As a water balance model of a given soil profile, the soil moisture depletion D, could be represented as the equation(2). 2. Among the various empirical formulae for potential evapotranspiration (Etp), Penman's formula was best fit to the data observed with the evaporation pans and tanks in Suweon area. High degree of positive correlation between Penman's predicted data and observed data with a large evaporation pan was confirmed. and the regression enquation was Y=0.7436X+17.2918, where Y represents evaporation rate from large evaporation pan, in mm/10days, and X represents potential evapotranspiration rate estimated by use of Penman's formula. 3. Evapotranspiration, Et, could be estimated from the potential evapotranspiration, Etp, by introducing the consumptive use coefficient, Kc, which was repre sensed by the following relationship: Kc=Kco$.$Ka+Ks‥‥‥(Eq. 6) where Kco : crop coefficient Ka : coefficient depending on the soil moisture content Ks : correction coefficient a. Crop coefficient. Kco. Crop coefficients of barley, bean, and wheat for each growth stage were found to be dependent on the crop. b. Coefficient depending on the soil moisture content, Ka. The values of Ka for clay loam, sandy loam, and loamy sand revealed a similar tendency to those of Pierce type. c. Correction coefficent, Ks. Following relationships were established to estimate Ks values: Ks=Kc-Kco$.$Ka, where Ks=0 if Kc,=Kco$.$K0$\geq$1.0, otherwise Ks=1-Kco$.$Ka 4. Effective rainfall, Re, was estimated by using following relationships : Re=D, if R-D$\geq$0, otherwise, Re=R 5. The difference between rainfall, R, and the soil moisture depletion D, was taken as drainage amount, Wd. {{{{D= SUM from { {i }=1} to n (Et-Re-I+Wd)}}}} if Wd=0, otherwise, {{{{D= SUM from { {i }=tf} to n (Et-Re-I+Wd)}}}} where tf=2∼3 days. 6. The curves and their corresponding empirical equations for the variation of soil moisture depending on the soil types, soil depths are shown on Fig. 8 (a,b.c,d). The general mathematical model on soil moisture variation depending on seasons, weather, and soil types were as follow: {{{{SMC= SUM ( { C}_{i }Exp( { - lambda }_{i } { t}_{i } )+ { Re}_{i } - { Excess}_{i } )}}}} where SMC : soil moisture content C : constant depending on an initial soil moisture content $\lambda$ : constant depending on season t : time Re : effective rainfall Excess : drainage and excess soil moisture other than drainage. The values of $\lambda$ are shown on Table 1. 7. The timing and amount of irrigation could be predicted by the equation (9-a) and (9-b,c), respectively. 8. Under the given conditions, the model for scheduling irrigation was completed. Fig. 9 show computer flow charts of the model. a. To estimate a potential evapotranspiration, Penman's equation was used if a complete observed meteorological data were available, and Jensen-Haise's equation was used if a forecasted meteorological data were available, However none of the observed or forecasted data were available, the equation (15) was used. b. As an input time data, a crop carlender was used, which was made based on the time when the growth stage of the crop shows it's maximum effective leaf coverage. 9. For the purpose of validation of the models, observed data of soil moiture content under various conditions from May, 1975 to July, 1975 were compared to the data predicted by Model-I and Model-II. Model-I shows the relative error of 4.6 to 14.3 percent which is an acceptable range of error in view of engineering purpose. Model-II shows 3 to 16.7 percent of relative error which is a little larger than the one from the Model-I. 10. Comparing two models, the followings are concluded: Model-I established on the theoretical background can predict with a satisfiable reliability far practical use provided that forecasted meteorological data are available. On the other hand, Model-II was superior to Model-I in it's simplicity, but it needs long period and wide scope of observed data to predict acceptable soil moisture content. Further studies are needed on the Model-II to make it acceptable in practical use.

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Organic Acidopathies as Etiologic Diseases of Developmental Delay in Korean Childhood and Adolescent Age Group (한국인 소아청소년기 발달지연의 원인질환으로서의 유기산대사이상질환)

  • Lee, Jong Yoon;Lee, Ye Seung;Choi, Joong Wan;Bae, Eun Joo;Park, Won Il;Oh, Phil Soo;Lee, Hong Jin
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.12 no.2
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    • pp.85-93
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    • 2012
  • Purpose: Developmental delay is caused by very diverse etiologic diseases. Most chronic disorders has some influence on development. Chronic or acute disorders of CNS are main etiologic diseases of developmental delay. Up to now, over 60 diseases are included in organic acidopathies and most of them causes acute or chronic recurrent CNS damage and developmental delay. We have done this study to find out the importance of organic acidopathies causing developmental delay in Korean childhood and adolescent patients. Method: Retrograde analysis for 738 patients with developmental delay whose clinical informations are available and have done urine organic acid analysis for 5 years period, between Jan. 1st 2007 to Dec. 31th 2011. Statistical analysis was done with Student's t test using SPSS. Result: Out of 738 patients, 340 patients (46.1%) showed abnormalities on urine organic acid analysis. The most frequent disease was mitochondrial respiratory chain disorders (MRCD) (253, 34.3%), followed by ketolytic defects(39, 5.3%), 3-hydroxyisobutyric aciduria (26, 3.5%), glutaric aciduria type II (8, 1.1%), pyruvate dehydrogenase deficiency (3, 0.4%), 3-methylglutaric aciduria (2, 0.3%), glutaric aciduria type I (2, 0.3%), ethylmalonic aciduria (1, 0.15%), methylmalonic aciduria (1, 0.15%), HMG-CoA lyase deficiency (1, 0.15%), 3-methylcrotonylglycinuria (1, 0.15%), fatty acid oxidation disorders(1, 0.15%) and FAOD (1, 0.15%). Conclusion: Mitochondrial disorders are most frequent etiologic disease on all age group, followed by ketolytic defects and various organic acidopathies. The number and diversities of organic acidopathies emphasize meticulous evaluation of basic routine laboratory examinations and organic acid analysis with initial sample on every developmental patient.

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Epidemiology of central venous catheter related blood stream infections in pediatric patients (중심정맥 도관 관련 감염의 역학 고찰)

  • Kim, Jung Hyun;Eun, Ho Sun;Choi, Kyung Min;Kim, Dong Soo;Young, Dong Eun
    • Clinical and Experimental Pediatrics
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    • v.49 no.2
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    • pp.157-161
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    • 2006
  • Purpose : The purpose of this study is to investigate the pathogens of central venous catheter-related blood stream infections and search for the association among the insertion site, the duration and the underlying conditions with the prevalence of central venous catheter-related blood stream infections under 15 years old. Methods : A retrospective study was performed from Jan, 2003 to Dec, 2003 in Severance Hospital on 112 patients who undertook central venous catheter insertions. Results : We examined 112 patients who undertook central venous catheter insertion. The mean age of patients was $4.77{\pm}4.12$ years old. Coagulase negative Staphylococci was the most common organism of central venous catheter-related blood stream infections accounting for 33.9 percent, followed by Eenterococcus faecium(9.3 percent), and Staphylococcus aureus(7.5 percent), The most common insertion site was the right femoral vein, followed by the right jugular vein and the left femoral vein. The mean insertion period was $14.17{\pm}12.00$ days. Conclusion : Central venous catheter-related blood stream infections were not only related to the underlying conditions, but also to the insertion site. We need to study the clinical importance of coagulase negative Staphylococci as it is part of the normal flora of the skin. In future, more studies are needed to take preventive measures and improve treatment methods.

Dynamic forecasts of bankruptcy with Recurrent Neural Network model (RNN(Recurrent Neural Network)을 이용한 기업부도예측모형에서 회계정보의 동적 변화 연구)

  • Kwon, Hyukkun;Lee, Dongkyu;Shin, Minsoo
    • Journal of Intelligence and Information Systems
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    • v.23 no.3
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    • pp.139-153
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    • 2017
  • Corporate bankruptcy can cause great losses not only to stakeholders but also to many related sectors in society. Through the economic crises, bankruptcy have increased and bankruptcy prediction models have become more and more important. Therefore, corporate bankruptcy has been regarded as one of the major topics of research in business management. Also, many studies in the industry are in progress and important. Previous studies attempted to utilize various methodologies to improve the bankruptcy prediction accuracy and to resolve the overfitting problem, such as Multivariate Discriminant Analysis (MDA), Generalized Linear Model (GLM). These methods are based on statistics. Recently, researchers have used machine learning methodologies such as Support Vector Machine (SVM), Artificial Neural Network (ANN). Furthermore, fuzzy theory and genetic algorithms were used. Because of this change, many of bankruptcy models are developed. Also, performance has been improved. In general, the company's financial and accounting information will change over time. Likewise, the market situation also changes, so there are many difficulties in predicting bankruptcy only with information at a certain point in time. However, even though traditional research has problems that don't take into account the time effect, dynamic model has not been studied much. When we ignore the time effect, we get the biased results. So the static model may not be suitable for predicting bankruptcy. Thus, using the dynamic model, there is a possibility that bankruptcy prediction model is improved. In this paper, we propose RNN (Recurrent Neural Network) which is one of the deep learning methodologies. The RNN learns time series data and the performance is known to be good. Prior to experiment, we selected non-financial firms listed on the KOSPI, KOSDAQ and KONEX markets from 2010 to 2016 for the estimation of the bankruptcy prediction model and the comparison of forecasting performance. In order to prevent a mistake of predicting bankruptcy by using the financial information already reflected in the deterioration of the financial condition of the company, the financial information was collected with a lag of two years, and the default period was defined from January to December of the year. Then we defined the bankruptcy. The bankruptcy we defined is the abolition of the listing due to sluggish earnings. We confirmed abolition of the list at KIND that is corporate stock information website. Then we selected variables at previous papers. The first set of variables are Z-score variables. These variables have become traditional variables in predicting bankruptcy. The second set of variables are dynamic variable set. Finally we selected 240 normal companies and 226 bankrupt companies at the first variable set. Likewise, we selected 229 normal companies and 226 bankrupt companies at the second variable set. We created a model that reflects dynamic changes in time-series financial data and by comparing the suggested model with the analysis of existing bankruptcy predictive models, we found that the suggested model could help to improve the accuracy of bankruptcy predictions. We used financial data in KIS Value (Financial database) and selected Multivariate Discriminant Analysis (MDA), Generalized Linear Model called logistic regression (GLM), Support Vector Machine (SVM), Artificial Neural Network (ANN) model as benchmark. The result of the experiment proved that RNN's performance was better than comparative model. The accuracy of RNN was high in both sets of variables and the Area Under the Curve (AUC) value was also high. Also when we saw the hit-ratio table, the ratio of RNNs that predicted a poor company to be bankrupt was higher than that of other comparative models. However the limitation of this paper is that an overfitting problem occurs during RNN learning. But we expect to be able to solve the overfitting problem by selecting more learning data and appropriate variables. From these result, it is expected that this research will contribute to the development of a bankruptcy prediction by proposing a new dynamic model.

Evaluation of Meteorological Elements Used for Reference Evapotranspiration Calculation of FAO Penman-Monteith Model (FAO Penman-Monteith 모형의 증발산량 산정에 이용되는 기상요소의 평가)

  • Hur, Seung-Oh;Jung, Kang-Ho;Ha, Sang-Keun;Kim, Jeong-Gyu
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.5
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    • pp.274-279
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    • 2006
  • The exact estimation of crop evapotranspiration containing reference or potential evapotranspiration is necessary for decision of crop water requirements. This study was carried out for the evaluation and application of various meteorological elements used for the calculation of reference evapotranspiration (RET) by FAO Penman-Monteith (PM) model. Meteorological elements including temperature, net radiation, soil heat flux, albedo, relative humidity, wind speed measured by meteorological instruments are required for RET calculation by FAO PM model. The average of albedo measured for crop growing period was 0.20, ranging from 0.12 to 0.23, and was slightly lower than 0.23. Determinant coefficients by measured albedo and green grass albedo were 0.97, 0.95 and standard errors were 0.74, 0.80 respectively. Usefulness of deductive regression models was admitted. To assess an influence of soil heat flux (G) on FAO PM, RET with G=0 was compared with RETs using G at 5cm soil depth ($G_{5cm}$) and G at surface ($G_{0cm}$). As the results, RET estimated by G=0 was well agreed with RET calculated by measured G. Therefore, estimated net radiation, G=0 and albedo of green grass could be used for RET calculation by FAO PM.