• Korean Journal of Agricultural and Forest Meteorology
• /
• v.21 no.2
• /
• pp.75-84
• /
• 2019

In this study, the random forest approach was used to predict the national mean rice yield of South Korea by using mean climatic factors at a national scale. A random forest model that used monthly climate variable and year as an important predictor in predicting crop yield. Annual yield change would be affected by technical improvement for crop management as well as climate. Year as prediction factor represent technical improvement. Thus, it is likely that the variables of importance identified for the random forest model could result in a large error in prediction of rice yield in practice. It was also found that elimination of the trend of yield data resulted in reasonable accuracy in prediction of yield using the random forest model. For example, yield prediction using the training set (data obtained from 1991 to 2005) had a relatively high degree of agreement statistics. Although the degree of agreement statistics for yield prediction for the test set (2006-2015) was not as good as those for the training set, the value of relative root mean square error (RRMSE) was less than 5%. In the variable importance plot, significant difference was noted in the importance of climate factors between the training and test sets. This difference could be attributed to the shifting of the transplanting date, which might have affected the growing season. This suggested that acceptable yield prediction could be achieved using random forest, when the data set included consistent planting or transplanting dates in the predicted area.

• Journal of the Korean Society of School Health
• /
• v.4 no.2
• /
• pp.100-118
• /
• 1991

This study was conducted in order to grasp the condition of the student's knowledge and attitude about sex. And to offer the basic materials for sex education of school health service. The objects were comprised of 464 volunteered students who study in commercial girls' high school. The material of this study was the questionaire suited to the purposed of this research which has been made through studying references. All the questionaire written by students. The self reported questionaires were collected immediately without explanation on supervision of school nurse. The data was collected from 28th to 30th of June on 1990. Analysis of the data was done utilizing SPSS for percentage, mean, ANOVA and Pearson Correlation Coefficients. The Results are as follows; 1. General features of the objects of study School grade distribution was similar. Fathers of 41-50 years were the highest(58.3%), mothers of 41-50 years were the highest(64.3%), family of living together were the highest(87.5%), fathers of graduated high school were highest(60.7%), mothers of graduated middle school were the highest(43.0%) and neuclear families were highest(91.5%). 2. The Conditions of Knowledge about sex When 5 Point was given to "Well known" and 1 point was given to "Never known", the total average was 2.97, Especially the mean of Female physiology was shown 3.93, 73.4% of students have known. But the mean of male physiology was shown 2.23, 17.2% of students only. And Family planning item was 3.54, hymen item was 3.38, female genitalia item was 3.35, abortion item was 3.25, Intercourse and pregnancy item was 3.24, Ovulation item was 3.02, Contraception item was 2.97, Veneral disease and masturbation item was 2.82, maintenance of pregnancy item was 2.76, Anatomical differences between male and female item was 2.59, male genitalia item was 2.31, ejaculation item was 2.27. 3. The conditions of attitude about Sex When 5 point was given to "Very affirming" and 1 point was given to "Very deny" the total average was 3.20. Especially the mean of social intercourse between other sex was shown 3.92, 73.4% of students have affirmed. But the mean of psychic response on menstruation was shown 2.24, 8.8% of students only. And baby birth item was 3.72, the fact that I am a woman item was 3.53, marriage item was 3.49. Secondary body change item was 3.38, puberty item was 3.31, delivery and sexual intercourse item was 3.05, pregenancy item was 3.02, psychic condition on menarche item was 2.50. Also present counsellors about sex were teachers in charge (44.9%), friends(21.6%), mothers(20.6%), elder sisters (10.6%), mass-communications (1.5%), fathers (0.4%), school nurses and elder brother(0.2%). In addition to, future counsellors about sex were friends (37.7%), mothers(30.6%), elder sister (18.4%), school nurses (4.6%), mass communication (3.8%), teachers in charge (2.5%), elder brothers (1.4%) and fathers(1.0%). 4. Correlation between the general features and knowledge variables School grade and knowledge condition has relationship to female genitalia(P<0.05), female physiology (P<0.00), male physiology (P<0.05),ovulation (P<0.00), and femily planning (P<0.005). Fathers age and knowledge condition has relationship to male physiology(P<0.05), and abortion (P<0.05). Marrital status and knowledge condition has relationship to female physiology (P<0.01), masturbation (P<0.05). Fathers educational background and knowledge condition has relationship to masturbation (P<0.00). Mothers age and knowledge condition has relationship to family planning (P<0.05). 5. Correlation between the general futures and attituded variables Fathers age and attitude condition has relationship to psychic response on menstruation (P<0.05). Mothers age and attitude condition has relationship to fact that I am a woman (P<0.00). Mothers educational background and attitude condition has relationship to social intercourse between other sex (P<0.05). Type of family and attitude condition has relationship to puberty (P<0.01). 6. Correlation between knowledge condition and attitude condition Those who had more knowledge about sex have more affirmative response (P<0.001).

• Korean Journal of Health Education and Promotion
• /
• v.24 no.5
• /
• pp.103-118
• /
• 2007

Housewives' perception on obesity related variables to their family members according to the composition of children in the family was explored. Ninety housewives responded to a questionnaire consisted of sociodemographic informations, body weight perception, eating behaviors perception, and physical activity level for herself as well as her family. They were categorized into three groups based on child composition of the family; boys only (BO), girls only (GO), and boys and girls (BG) families. Boys in BO showed higher value of height, weight, and WHR than girls in GO (p <.05), while no differences were noticed in BMI and the waist girth between the groups. Mothers of BO perceived boys were active while mother of GO did girls were inactive (p <.05). Girls in GO ate meals less regularly than boys in BO and girls in BG. In general, housewives' perception on body weight of family members was relied on BMI and waist girth. As mother's BMI increased, the boy's BMI in BO was also elevated (p <.05), but not in others. Mothers' perception on caloric intake and activity encouragement were not accounted for morphological characteristics. Results suggest that housewives perceived obesity related variables differently based on the composition of children of the family.

• Journal of Korean Medicine Rehabilitation
• /
• v.27 no.4
• /
• pp.97-109
• /
• 2017

Objectives The aim of this study is to analyze the patients who have low back pain through registry. Methods We registered patients with low back pain who visited department of korean rehabilitation medicine in university hospitals on study. We collected data from 116 subjects consisted of 51 inpatients and 65 outpatients and ruled out 8 who didn't have pattern identification data at the point of inpatient or outpatient visit so we analyzed 108 in total. We used Pearson's product moment correlation to find correlationship among variables, and analyzed statistical data using Phyton scipy library stats package. Results We set general features, region of the pain, physical examination, ROM, questionnaire results, pattern identification as variables and draw a conclusion by analyzing these variables. Conclusions Registry aimed at low back pain patients was established in department of korean rehabilitation medicine of university hospitals and exploratory analysis based on data were made. Through the registry, we expect that more advanced studies will be performed; for example, executing research which verifies effectiveness and stability of korean medical treatment or developing tools to fill the gap between pattern identification and disease identification.

• The Korean Journal of Physiology and Pharmacology
• /
• v.13 no.5
• /
• pp.357-360
• /
• 2009

It is hypothesized that a number of environmental factors affect animals' behavior. Without controlling these variables, it is very hard for researchers to get not only reliable, but replicable data from various behavioral experiments testing animals' cognitive as well as emotional functions. For example, laboratory mice which had restricted environment showed different synaptic potentiation properties with wild mice (Zhao MG et al., 2009). While performing behavioral experiments, however, it is sometimes inevitable that the researcher changes the animals' environments, as by switching the cages in which experimental animals are housed and separating animals raised together into small experimental groups. In this study, we investigated the effect of environmental changes on mice's emotional behaviors by socially isolating them or reducing the size of their cage. We found that social isolation selectively increases the animals' levels of anxiety, while leaving depression-like behaviors unchanged. On the other hand, alteration of the housing dimensions affected neither their anxiety levels nor their depression-like behaviors. These results suggest that environmental variables may have a prominent impact on experimental animals' emotional behaviors and possibly their psychological states, leading to bias in the behavioral data produced from experiments.

• Korean Journal of Health Education and Promotion
• /
• v.32 no.5
• /
• pp.73-81
• /
• 2015

Objectives: We tried to confirm physical activity of 1,000 Kcal per week was a meaningful point in controlling coronary artery disease risks in female older adults. Methods: Participants were 66 female older adults recruited from senior welfare center. Participants were provided with accelerometer (e-step, Kenz, Japan) for measuring daily energy expenditure. Graded exercise test was done for measuring aerobic fitness. Blood glucose and lipid were analyzed. Framingham risk score was calculated based on blood glucose, blood lipid, and smoking. These variables were compared between the group expended more than 1,000 Kcal/week and the group with energy expenditure below 1,000 Kcal/week. Results: The group expended over 1,000kcal/week showed to be superior to the counterpart group in following variables; AC(Abdominal Circumference), %BF, $HR_{rest}$(resting heart rate), $VO_{2peak}$, FBG, LDL-C, TG, BDI-II, QOL, AR(Absolute Risk), RR(Relative Risk). Conclusions: The group expended over 1,000 Kcal/week was likely to have less probability in CAD than group expended less than 1,000 Kcal/week. The result of this study suggests the important role of active daily life that can be replaced with that of regular exercise especially for those who are not available to do structured exercise.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.4
• /
• pp.330-336
• /
• 2022

It is likely that the heading would occur early when air temperature increases. In 2022, however, the heading date was delayed unusually, e.g., by 3 to 5 days although temperature during the vegetative growth stage was higher than normal years. The objective of this study was to identify the cause of such event analyzing weather variables including average temperature, sunshine hours, and day-length for each growth stage. The observation data were collected for medium-late maturing varieties, which has been grown at crop yield experiment sites including Daegu, Andong, and Yesan. The difference in heading date was compared between growing seasons in 2021 and 2022 because crop management options, e.g., the cultivars and cultivation methods, were identical at those sites during the study period. It appeared that the heading date was delayed due to the difference in temperature responsiveness under a given day-length condition The effect of the temperature increase on the heading date differed between the periods during which when the day-length was more than 14.3 hours before and after the summer-solstice.. The effect of the temperature decrease during the period from which the day-length decreased to less than 14.3 hours to the heading date was relatively greater. This merits further studies to examine the response of rice to the temperature change under different day-length and sunshine duration in terms of heading.

• The Korean Journal of Physiology
• /
• v.27 no.2
• /
• pp.209-215
• /
• 1993

The aim of the present study was to derive regression equations for $\dot{V}o_{2max}\;vs.\;\dot{V}o_{2peak},\;and\;\dot{V}o_2\;vs.$ heart rate, exercise time, and other variables from maximal exercise tests on a treadmill using the Bruce and inclined protocols. Twelve male and 10 female Korean college students aged between 19 and 23 years voIunteered for this study. After the resting measurements, the subjects performed a maximal exercise on a treadmill according to the Bruce protocol. When the resting conditions were restored, the subjects performed another maximal exercise according to an inclined protocol where the speed was fixed at 8.05 $km{\cdot}h^{-1}$ and the grade was incremented starting from 09t by 2.5% for every 2 min. Peak $\dot{V}o_2$ observed during the Bruce exercise $(\dot{V}o_{2peak})$ was $37.7{\pm}2.4\;and\;31.7{\pm}1.8\;ml\;kg^{-1}\;min^{-1}$ in the male and female groups, respectively. Peak $\dot{V}o_2$ observed during the inclined exercise was higher than $\dot{V}o_{2peak}$ during the Bruce exercise. Maximum $\dot{V}o_2$ value observed during the tyro exercises $(\dot{V}o_{2max})$ was $43.0{\pm}2.8\;and\;36.2{\pm}1.4\;ml\;kg^{-1}\;min^{-1}$ in the male and female groups, respectively. Thus, $\dot{V}o_{2peak}$ by the Bruce protocol was about 12% (male) or 13% (female) lower than $\dot{V}o_{2max}$, and a linear relationship was found between $\dot{V}o_{2peak}$ and $\dot{V}o_{2max}$. The peak values of % $\dot{V}o_{max}$ with the Bruce protocol were $89.2{\pm}3.3\;and\;87.5{\pm}3.6%$ and those with the inclined protocol $97.7{\pm}1.8\;and\;96.9{\pm}2.0%$ in the male and female groups, respectively. In the female group, $%\dot{V}o_{2max}$ at a given workload was higher than in the male group, while $\dot{V}o_{2}$ per kg body weight was the same. Maximum HR observed during the two exercises was $204{\pm}2\;and\;195{\pm}3\;beat\;min^{-1}$ in the male and female groups, respectively. Linear relationships were found, excluding the last points, between 1) $\dot{V}o_{2}$ and exercise time, 2) $\dot{V}o_{2}$ and $%\dot{V}o_{2max}\;and\;%HR_{max}$.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.26 no.5
• /
• pp.621-629
• /
• 2012

This study aimed to examine the possibility of data from pulse diagnosis device to be used for diagnosis of Sasang constitution. Systematic searches of 5 major Korean medical database were conducted for articles published up to May 2012. Searching key word was "Sasang" or "Constitution". Studies dealt with correlation between Sasang constitution and the pulse wave data from pulse diagnosis machine were included. Totally 2886 studies are searched and 3 studies are added from references of evaluated articles. Among them, 12 studies were met our inclusion criteria (2 Xishu Mac, 2 Self-made pulse diagnosis machine, 8 3D-Mac). Three of the eight 3D-Mac studies intended to develop a formula of constitutional differential diagnosis, 2 studies compared variables by Sasang constitution in healthy group and 3 studies compared variables by Sasang constitution in healthy group and special disease group. They all reported some significant variables, however results are not consistent between studies. The accuracy of the formula of constitutional differential diagnosis using 3D-Mac pulse diagnosis devices is 46.0% by now. Improvements in measuring pulse are required to achieve more accurate result and be used for diagnosis of Sasang constitution. Compensating B.M.I. among Sasang constitutional groups and separating constitutional pulse factors from acquired characteristics are also needed in further study.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.22 no.4
• /
• pp.239-249
• /
• 2020

Rice flour varieties have been developed to replace wheat, and consumption of rice flour has been encouraged. damage related to pre-harvest sprouting was occurring due to a weather disaster during the ripening period. Thus, it is necessary to develop pre-harvest sprouting rate prediction system to minimize damage for pre-harvest sprouting. Rice cultivation experiments from 20 17 to 20 19 were conducted with three rice flour varieties at six regions in Gangwon-do, Chungcheongbuk-do, and Gyeongsangbuk-do. Survey components were the heading date and pre-harvest sprouting at the harvest date. The weather data were collected daily mean temperature, relative humidity, and rainfall using Automated Synoptic Observing System (ASOS) with the same region name. Gradient Boosting Machine (GBM) which is a machine learning model, was used to predict the pre-harvest sprouting rate, and the training input variables were mean temperature, relative humidity, and total rainfall. Also, the experiment for the period from days after the heading date (DAH) to the subsequent period (DA2H) was conducted to establish the period related to pre-harvest sprouting. The data were divided into training-set and vali-set for calibration of period related to pre-harvest sprouting, and test-set for validation. The result for training-set and vali-set showed the highest score for a period of 22 DAH and 24 DA2H. The result for test-set tended to overpredict pre-harvest sprouting rate on a section smaller than 3.0 %. However, the result showed a high prediction performance (R2=0.76). Therefore, it is expected that the pre-harvest sprouting rate could be able to easily predict with weather components for a specific period using machine learning.