• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.252-264
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• 2023

This paper proposes a design of a dual-band band-pass filter that integrates a λg/2 open SIR structure, a transmission line, and a fork-type structure with symmetric and asymmetric open stubs. To obtain the dual-band effect, the proposed filter uses the SIR structure and adjusts the impedance ratio of the SIR structure. Therefore, the position of the harmonics of the filter is shifted through the adjustment of the impedance ratio, and this can obtain a double-band effect. In order to obtain the dual-band characteristics, the dual-band effect is obtained by inserting a open stub between the SIR structures with the SIR structure divided in half. In addition, the second frequency response is obtained by adjusting the length of the open symmetrical stub in the fork-shaped structure. The asymmetrical open stub in the fork form achieves optimum bandwidth by adjusting the length. Therefore, the first center frequency of the proposed band-pass filter is 5.896 GHz and the bandwidth is 13.6 %. At this time, the measurement results are 0.13 dB and 33.6 dB. The second center frequency is 5.906 GHz and the bandwidth is 13.6 %. At this time, the measurement results are 0.15 dB and 19.8 dB. The reason is that when the impedance ratio (Δ) is higher than 1, the position of the harmonic is shifted to a lower frequency band. However, if the impedance ratio (Δ) is lowered by one step, the position of harmonics will move to a higher frequency band. The function of the filter designed using these characteristics can be obtained from the measurement result. The proposed band-pass filter has no coupling loss and no via energy concentration loss because there is no coupling structure of input/output and no via hole. Therefore, system integration is possible due to its excellent performance, and it is expected that dedicated short-range communication (DSRC) system applications used in traffic communication systems will be possible.

• Journal of Korea Water Resources Association
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• v.56 no.4
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• pp.261-272
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• 2023

In recent years, natural disasters such as heavy rainfall and typhoons have occurred more frequently, and their severity has increased due to climate change. The Korea Meteorological Administration (KMA) currently uses the same criteria for all regions in Korea for watch and warning based on the maximum cumulative rainfall with durations of 3-hour and 12-hour to reduce damage. However, KMA's criteria do not consider the regional characteristics of damages caused by heavy rainfall and typhoon events. In this regard, it is necessary to develop new criteria considering regional characteristics of damage and cumulative rainfalls in durations, establishing four stages: blue, yellow, orange, and red. A classification model, called DSCM (Disaster Severity Classification Model), for the four-stage disaster severity was developed using four machine learning models (Decision Tree, Support Vector Machine, Random Forest, and XGBoost). This study applied DSCM to local governments of Seoul, Incheon, and Gyeonggi Province province. To develop DSCM, we used data on rainfall, cumulative rainfall, maximum rainfalls for durations of 3-hour and 12-hour, and antecedent rainfall as independent variables, and a 4-class damage scale for heavy rain damage and typhoon damage for each local government as dependent variables. As a result, the Decision Tree model had the highest accuracy with an F1-Score of 0.56. We believe that this developed DSCM can help identify disaster risk at each stage and contribute to reducing damage through efficient disaster management for local governments based on specific events.

• Journal of agriculture & life science
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• v.50 no.2
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• pp.107-116
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• 2016

The study was aimed to analyze pedigree structure and inbreeding coefficients for performance tested Holstein cows in Korea. A total of 400,029 Holstein cows data which born between 2002 and 2012 were obtained from Dairy Cattle Improvement Center of National Agricultural Cooperative Federation(NACF). Their related pedigrees, as obtained from Korean Animal Improvement Association(KAIA), consisted of 509,740 animals. Pedigree depth of the cows were traced back to 3 generations earlier. The percentage of cows with fully identified ancestors in various provinces of Korea were 55.18%(Gyeonggi-do), 23.49%(Gangwon-do), 47.83%(Chungcheongnam-do), 53.62%(Chungcheongbuk-do), 56.38%(Gyeongsangbuk-do), 51.35% (Gyeongsangnam-do), 26.58%(Jeollanam-do), 49.41%(Jeollabuk-do), and 56.90%(Jeju-do), whereas, it was about 63.20% as a whole in Korea. The average inbreeding coefficients showed increment across the consecutive years of birth such as, 0.43(2002), 0.44(2003), 0.58(2004), 0.64(2005), 0.78(2006), 0.93(2007), 1.08(2008), 1.23(2009), 1.46(2010), 1.77(2011), and 2.03 (2012). However, this coefficient was 0.93 in overall Korean population. An average generation interval for sire to daughter genetic path was 8.15 years; which was about 4.20 years considering dam to daughter genetic path. The estimated effective population sizes (Ne) were 56.5, 51.3, and 32.2 animals born in 2004, 2009, and 2012, respectively. These results indicated that an increased rate of inbreeding has led to a significant reduction in the Ne over the decade.

• 한국체육학회지인문사회과학편
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• v.54 no.1
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• pp.553-566
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• 2015

This study was performed to identify the effects of different intensities of regular aerobic exercise on erythropoietin (EPO) and BDNF levels, and cognitive function and working memory in middle-aged women. Women aged 40 to 60 years residing in G-gu, Y-si, Gyeonggi-do were divided into 3 groups: control group, moderate-intensity aerobic exercise group and high-intensity aerobic exercise. All groups were asked to exercise at the given intensities, twice a week for a total of 12 weeks. Blood samples were collected from participants on week 0 (before exercising), week 6 and week 12, and then cognitive function and working memory tests were followed to measure erythropoietin (EPO) and BDNF levels, cognitive function and working memory. Repeated measures ANOVA, univariate analysis and follow-up test were performed on all data to compare the group, period and interaction through a SPSS. As a result, a significant difference over time was observed in EPO, BDNF, cognitive function and working memory; therefore, a follow-up one-way ANOVA analysis was performed on each group. As a result of analysis, a significant increase in erythrocyte, hematocrit, BDNF level and working memory was observed in moderate-intensity aerobic exercise group while erythrocyte and working memory were significantly increased inhigh-intensity aerobic exercise group. When comparing the results between the groups, the level of hematocrit was shown to be significantly higher in both moderate-and high-intensity aerobic group than the control group and also the higher level of hemoglobin was observed in both moderate-and high-intensity aerobic group comparing to control group. Considering the results of this study, therefore, a 12-week long aerobic exercise at moderate to high intensity positively affected EPO and BDNF levels, cognitive function and working memory in middle-aged women.

• Korean Journal of Environment and Ecology
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• v.37 no.3
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• pp.221-231
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• 2023

Great tit (Parus major) is a bioindicator species that can measure environmental changes in urban ecosystems and plays an important role in maintaining health as a representative insectivorous bird. Researchers have utilized artificial nest box surveys to understand the reproductive ecology of the Paridae family of birds, including the Great tits, but it is difficult to conduct a macroscopic study due to spatial and temporal limitations. This study designed and applied a citizen-participatory monitoring of artificial nest boxes project to transcend the limitations of expert-centered monitoring methods. The Suwon Front Yard Bird Monitoring Team installed artificial nest boxes in green spaces in Suwon, Gyeonggi Province and observed the reproductive ecology of the Paridae family through the participation of voluntary citizen surveyors. Participants were recruited through an online survey from February 9 to February 22, 2021, and they directly performed from installation to observation of artificial next boxes from February 23 to August 31, 2021. Online education was provided to the volunteers for the entire monitoring process to lower the entry barrier for non-expert citizen surveyors and collect consistent data, and observation records were collected through a mobile app. A total of 98 citizen surveyors participated in the citizen-participatory monitoring of artificial nest boxes project, and 175 (84.95%) of the 256 distributed artificial nest boxes were installed in green spaces in Suwon City. Among the installed artificial nest boxes, the results of the citizen science project were confirmed for 173 (83.98%), excluding two boxes with position coordinate generation errors. A total of 987 artificial nest box observation records were collected from citizen surveyors, with a minimum of one time, a maximum of 26 times, and an average of 5.71±4.37 times. The number of observations of artificial birdhouses per month was 70 times (7.09%) in February, 444 times (44.98%) in March, 284 times (28.77%) in April, 133 times (13.48%) in May, 46 times (4.66%) in June, 6 times (0.61%) in July, and 4 times (0.41%) in August. Birds using the artificial nest boxes were observed in 57 (32.95%) of the 173 installed artificial nest boxes, and they included Great tit (Parus major) using 12 boxes (21.05%), Varied Tit (Parus varius) using 7 boxes (12.28%), and unidentified birds using 38 boxes (66.67%). This study is the first to consider citizen participation in the monitoring of artificial nest boxes, a survey method for the reproductive ecology of the Paridae family, including Great tits, and it can be utilized as basic data for the design of ecological monitoring combined with citizen science in the future.

• Journal of Korea Water Resources Association
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• v.56 no.5
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• pp.311-323
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• 2023

In order to reduce disaster damage by localized heavy rains, floods, and urban inundation, it is important to know in advance whether natural disasters occur. Currently, heavy rain watch and heavy rain warning by the criteria of the Korea Meteorological Administration are being issued in Korea. However, since this one criterion is applied to the whole country, we can not clearly recognize heavy rain damage for a specific region in advance. Therefore, in this paper, we tried to reset the current criteria for a special weather report which considers the regional characteristics and to predict the damage caused by rainfall after 1 hour. The study area was selected as Gyeonggi-province, where has more frequent heavy rain damage than other regions. Then, the rainfall inducing disaster or hazard-triggering rainfall was set by utilizing hourly rainfall and heavy rain damage data, considering the local characteristics. The heavy rain damage prediction model was developed by a decision tree model and a random forest model, which are machine learning technique and by rainfall inducing disaster and rainfall data. In addition, long short-term memory and deep neural network models were used for predicting rainfall after 1 hour. The predicted rainfall by a developed prediction model was applied to the trained classification model and we predicted whether the rain damage after 1 hour will be occurred or not and we called this as 1ST-Model. The 1ST-Model can be used for preventing and preparing heavy rain disaster and it is judged to be of great contribution in reducing damage caused by heavy rain.

• Journal of Nutrition and Health
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• v.56 no.3
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• pp.247-263
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• 2023

Purpose: This study was conducted to update the Nutrition Quotient for Adolescents (NQ-A), which is used to assess the overall dietary quality and food behavior among Korean adolescents. Methods: The first 30 candidate items of the measurable eating behavior checklist were obtained based on a previous NQ-A checklist, the results of the seventh Korea National Health and Nutrition Examination Survey data, Korea Youth Risk Behavior Survey data, national nutrition policies and dietary guidelines, and literature reviews. A total of 100 middle and high school students residing in Seoul and Gyeonggi Province participated in a pilot study using the 25-item checklist. Factor analysis and frequency analysis were conducted to determine if the checklist items were organized properly and whether the responses to each item were distributed adequately, respectively. As a result, 22 checklist items were selected for the nationwide survey, which was applied to 1,000 adolescent subjects with stratified sampling from 6 metropolitan cities. The construct validity of the updated NQ-A 2021 was assessed using confirmatory factor analysis. Results: Twenty checklist items were determined for the final NQ-A 2021. The items were composed of three factors: balance (8 items), moderation (9 items), and practice (3 items). The standardized path coefficients were used as the weights of items to determine the nutrition quotients. NQ-A 2021 and 3-factor scores were calculated according to the weights of questionnaire items. The weight for each of the 3 factors was determined as follows: balance, 0.15; moderation, 0.30; and practice, 0.55. Conclusion: The updated NQ-A 2021 is a useful instrument for easily and quickly evaluating the dietary qualities and eating behaviors of Korean adolescents.

• Journal of Korean Historical Folklife
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• no.33
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• pp.115-143
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• 2010

The purpose of this study is to analyze contents and process of rites about sacrificial rites related Royal Mausoleums in early Joseon Dynasty, and to conclude, to review the position of Royal Mausoleums in the whole National Rites System. The sacrificial rites related Royal Mausoleums started from building Royal Mausoleums of 8 persons-ancestors since King T'aejo's great-great-grandparents, in 1392, founding Joseon Dynasty. In 1408, King T'aejo had died and his Kŏnwŏnnŭng (健元陵) was builted in Yangju, Gyeonggi-do. Since then, after kings of many generations died, each of Royal Mausoleums was builted solemnlly. In the process of this, sacrificial rituals modified and supplemented, especially during the reign of king Sejong(1418~1450). After all, the sacrificial rites related Royal Mausoleums was settled in KukchoOryeūi(國朝五禮儀, Five State Rites) compiled during the reign of King Sŏngjong. In process of Institutionalization of sacrificial rituals, the argument between king and vassals about four-seasons' ancestral rites was properly or not was occurred. That was because the memorial times of Royal Mausoleums overlaped Chongmyo's and more important Chongmyo's ancestral rites was neglected. But four-seasons' ancestral rites of Royal Mausoleums was continued until 17th century. Sacrificial rites related Royal Mausoleums as royal personal rites had simple processes compared to sacrificial rites of Chongmyo, upper-graded formal ancestral rites, under National Rites system. Justifying to served his parents with devotion, the kings in early Joseon Dynasty went to Royal Mausoleums 2-3 times annually. During coming and going, he show off his presence as king in power to his subjects through magnificent guard of honor. On the one hand, he met his subjects directly and acceded to various petition. Above all things, The kings in early Joseon Dynasty emphasized his military power through military training, namely, hunting, disposition of troops, and so on.

• 한국노년학
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• v.31 no.3
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• pp.505-526
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• 2011

The purposes of this paper were to examine the level of knowledge of and attitudes toward the elderly and investigate the differences in the level of knowledge of and attitudes about the elderly by selected socio-demographic factors and aging related factors in Korea and the United States. The research subjects were 1129 college students attending 10 schools in Korea and the United States(840 Korean students in 5 schools, located in Seoul City, Gyeonggi-Do, Chungcheong-Do in Korea and 289 American students in 5 schools located in the State of New York of the United States). They were interviewed, using the structured questionnaire, and the data were analyzed by SPSS 15.0 for Windows. The research questionnaire was composed of Fact on Aging Quiz Part 1(FAQ 1) developed by Palmore(1998), Semantic Differential Scale development by Sanders et al., and several socio-demographic and aging related variables. The results indicated that, first, the level of knowledge of the elderly for Korean students was 12.51/25 and for American students was 11.57/25, resulting that the knowledge level of the elderly in Korea was higher than that of the United States. In addition, the results of students' knowledge differences between korea and the United States showed that Korean students showed high ratio of correct answer in 9 questions while American students showed high ratio of correct answer in only 4 questions, resulting that Korean students have higher knowledge than American students. Second, the level of attitudes toward the elderly for Korean students was 77.54 and for American students was 70.07 in 20-140 points, resulting that the attitude level of the elderly among American students were more positive than that of Korean students. The results of students' attitudes differences between Korea and the United States showed that Korean students responded positive tendency in only one question while American students responded positive tendencies in 14 questions, resulting that American students were more positive attitudes toward the elderly than that of Korean students. Third, there is a significant correlation between the knowledge of and attitudes toward the elderly in both Korean and American students. Based on these results, implications for policy, practice, and research were further discussed.

• Korean Journal of School Psychology
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• v.16 no.3
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• pp.471-499
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• 2019

The purpose of this study was to develop a program that reduces adolescent delinquency and enhances adolescents' social problem-solving, emotional regulation, and self-control skills and to assess the effectiveness of the program. The program was administered in the form of a role-playing game ("RPG") to increase the participants' motivation to participate in and the effectiveness of the therapy. The subjects in this study were 36 adolescents who engaged in delinquent behavior and their 18 homeroom teachers in middle schools located in Seoul and Gyeonggi Province. The subjects were randomly assigned to the experimental group or the comparison group. The experimental group received the proposed RPG-based cognitive behavioral group therapy while comparison group received problem-solving group therapy. Teachers in the experimental group were educated about how to guide their students following each therapy session while teachers in the comparison group did not receive any education. The dependent variables in this study were incidences of delinquent behavior and social problem-solving, emotional regulation, and self-control skill level. Each variable was assessed before treatment, immediately after the end of the full treatment program, and two months after the end of the full treatment program. At the end of the full treatment program, the experimental group engaged statistically significantly in fewer delinquent behaviors and displayed statistically significantly higher levels of social problem-solving, emotional regulation, and self-control skills than the comparison group. These differences persisted until the assessment two months after the end of the full treatment program. Moreover, the experimental group reported higher levels of satisfaction with the treatment program than the comparison group. The findings of this study suggest that this RPG-based cognitive behavioral group therapy program is effective at reducing adolescent delinquency, improving adolescents' social and emotional management techniques and strategies for avoiding delinquency, and in motivating delinquent adolescents to engage more actively in treatment.