Carbon is not only an essential element for life but also a key player in climate change. The radiocarbon (14C) analysis using accelerator mass spectrometry (AMS) is a powerful tool not only to understand the carbon cycle but also to track pollutants derived from fossil carbon, which have a distinct radiocarbon isotope ratio (Δ14C). Many studies have reported Δ14C of carbon compounds in streams, rivers, rain, snow, throughfall, fine particulate matter (PM2.5), and wastewater treatment plant effluents in South Korea, which are reviewed in this manuscript. In summary, (1) stream and river carbon in South Korea are largely derived from the chemical weathering of soils and rocks, and organic compounds in plants and soils, strongly influenced by precipitation, wastewater treatment effluents, agricultural land use, soil water, and groundwater. (2) Unprecedentedly high Δ14C of precipitation during winter has been reported, which can directly and indirectly influence stream and river carbon. Although we cannot exclude the possibility of local contamination sources of high Δ14C, the results suggest that stream dissolved organic carbon could be older than previously thought, warranting future studies. (3) The 14C analysis has also been applied to quantify the sources of forest throughfall and PM2.5, providing new insights. The 14C data on a variety of ecosystems will be valuable not only to track the pollutants derived from fossil carbon but also to improve our understanding of climate change and provide solutions.

PURPOSES : The purpose of this study is to identify the beneficiaries of car-sharing that can utilize autonomous car-sharing services when they are introduced. METHODS : This study was conducted in two stages. The first step was to analyze the characteristics of shared car usage by region and rental time using t-Ttest. The second step was to analyze the beneficiaries of autonomous car-sharing services if they are introduced. The beneficiaries were derived using parking time and survey data. RESULTS : Car-sharing behavior showed statistically different usage characteristics by region and rental period. However, the distance traveled per trip for short trips was similar. When the autonomous car sharing service with free return and rental is introduced, 31% (Jeju) to 38% (Daejeon) of short-term renters and 50 to 52% of long-term renters are expected to benefit. CONCLUSIONS : When introducing autonomous car-sharing services, it is necessary to establish a shared car strategy that reflects the characteristics of car-sharing use by region and rental period. In particular, in Jeju Island, where the rental time is relatively longer than Daejeon, the introduction of autonomous car-sharing services will contribute to reducing the cost of shared vehicles in terms of cost.

2015년부터 2022년도까지 6개목(딱정벌레목, 노린재목, 나비목, 벌목, 파리목, 총채벌레목) 곤충들에 대해서 식물검역현장 검출실적과 국내 보고된 미기록종을 분석하였다. 해당기간 동안 국경검역에서 6개목 곤충은 총 45,084건이 검출되었다. 같은 기간 국내에서는 총 545종이 미기록종 으로 보고되었으며, 이중 9종은 국경검역에서도 검출된 것으로 확인되었다. 검역현장에서는 딱정벌레목, 총채벌레목, 노린재목이 높은 검출률을 보 였으며, 국내 미기록종 중에서는 벌목이 176종으로 가장 많이 보고되었다. 본 연구를 통해 침입압력(국경검역 검출)과 실제 침입(국내 미기록종 발 견) 사이에 비동시성이 확인되었다. 향후 보다 장기적인 분석이 필요할 뿐만 아니라 지속적인 식물검역시스템 개선이 필요할 것으로 판단된다.

Tomato is one of the major widely cultivated crops around the world. The leaf area is directly related to the total amount of photosynthesis, which affects the yield and quality of the fruit. Traditional methods of measuring the leaf area are time-consuming and can cause damage to the leaves. To address these problems, various studies are being conducted for measuring the leaf area. In this study, we introduced a model to estimate the leaf area using images of tomatoes. Using images captured by a camera, we measured the leaf length and width and used linear regression analysis to derive the leaf area estimation formula. Furthermore, we used a Neural Network (NN) for additional analysis to compare the accuracy of the models. Initially, to verify the reliability of the image data, we conducted a correlation analysis between the actual measurement data and the image data, which showed a high positive correlation. The leaf area estimation model presented 23 estimation formulas. We used regression analysis to estimate the coefficients of each model and also used employed an artificial neural network analysis to derive high R-squared (R2) values and low Root Mean Square Error (RMSE) values. Among the estimation formulas, the ninth model showed the highest reliability with an R-squared value of 0.863. We conducted a verification experiment to confirm the accuracy of the selected model, and the R-squared value was 0.925. This study confirmed the reliability of data measured from images and the reliability of the leaf area estimation model using image data. These methods are expected to be an important tool in agriculture, using imaging equipment for measuring and monitoring the crop growth.

PURPOSES : This study aims to understand the characteristics of accidents involving autonomous vehicles and derive the causes of accidents from road spatial information through autonomous vehicle accident reports. METHODS : For this study, autonomous vehicle accident reports collected and managed by the CA DMV were used as data sources. In addition, spatial characteristics and geometric data for accident locations were extracted by Google maps. Based on the collected data, the study conducted general statistics, text embedding, and cross-analysis to understand the overall characteristics of autonomous vehicle accidents and their relationship with road spatial features. RESULTS : The analysis results for characteristics of autonomous vehicle accidents, applying statistical analysis and text embedding techniques, reveal that the damages caused by autonomous vehicle accidents are often minor, and approximately half of the accidents are triggered by other vehicles. It is noteworthy that accidents where autonomous vehicles are at fault are not uncommon, and when the cause of the accident is within the autonomous vehicle, the accident risk can increase. The accident analysis results using spatial data showed that the severity of accidents increases when on-street parking is present, when dedicated lanes for bicycles and buses exist, and when bus stops are present. CONCLUSIONS : Through this study, geometric and spatial elements that appear to have an impact on autonomous driving systems have been identified. The findings of this study are expected to serve as foundational data for improving the safety of autonomous vehicle operations in the future.

PURPOSES : This study is to analyze preference of shared personal mobility(shared e-scooter or shared bike) parking lot. The detailed purposes are as follows. Firstly, the attributes and attribute levels of shared personal mobility are developed. Based on combined attributes and attribute levels several profiles were composed. Preference data of shared personal mobility parking lot is collected through survey. Preference of shared personal mobility parking lot was analyzed using conjoint analysis. METHODS : Based on the literature review, the attributes and attribute levels that might affect behavior or intention of shared personal mobility parking were developed. Several profiles that contain combined attributes and attribute levels were created in a fractional factorial design. In order to collect preference data of shared personal mobility parking lot, online survey were proceeded. The survey participants were asked to mark preference point between point 1 and point 10. Lastly, preference of shared personal mobility parking lot was analyzed using conjoint analysis. RESULTS : Based on literature review, 5 attributes for conjoint analysis were set.(Distance between shared personal mobility parking lot and destination, Space for shared personal mobility parking lot, Location of shared personal mobility parking lot, Type of shared personal mobility parking lot, Interval of shared personal mobility parking lot). With the combination of 5 attributes and their levels, 16 random profiles were made. Online survey was proceeded with 300 participants who have used shared personal mobility. Using conjoint analysis utility and importance of each attribute has been calculated. As a result, the preference got higher when distance between parking lot and destination and intervals of parking lots are short. In addition racks are tended to be preferred and it seems to be more profer to install parking lot on buffer zone of pedestrian road instead of adjacent to private building. CONCLUSIONS : It could be important to install personal mobility parking lot considering preference of parking lot attributes in order to encourage users to use the proper parking lot instead of parking anywhere.

European and Turkish rice varieties were analysed to identify the traits associated with low-temperature germination. The aim of the study is to develop new rice varieties that can use these traits to reduce greenhouse gas emissions in rice fields. The average low temperature germination ratio (GR) in the European and Turkish rice varieties was 89.0±14.1%. The speed of the germination rate (SG) in Korean early maturing varieties, ‘Jopyeong’ and ‘Baekilmi’ was 1.3 and 3.5, respectively, whereas the European and Turkish varieties had a SG of 6.6. In terms of germination energy (GE) by the date, the European and Turkish varieties started germination within 4 days, while ‘Jopyeong’ and ‘Baekilmi’ began to germinate after 8 and 10 days, respectively. The mean germination time (MGT) for the European and Turkish varieties was 9.9±1.2 days. Between 4 to 10 days after inoculation, the germination velocity coefficient (GVC) for the European and Turkish varieties increased moderately from 2.6 to 5.3. After 10 days, the GVC rose rapidly from 7.0 to 12.0. ‘Jopyeong’ and ‘Baekilmi’ had slower germination rates compared to the European and Turkish varieties, in which the GVC increased moderately to 3.2 and 2.3, respectively, between 7 and 9 days after inoculation. The average mesocotyl elongation ability was 4.0±0.4 cm, with a range from 1.3 cm to 7.3 cm.

Lee, Jeongbok. (2023). “Analysis of Netizens' Attitudes Toward the Language of K-pop Lyrics: Focusing on BTS”. The Sociolinguistic Journal of Korea, 31(4), 235-277. This study analyzes the language of K-pop lyrics and netizens’ attitudes toward it to clarify the relationship between K-pop lyrics and the Korean language. The number of K-pop songs written in English is increasing, and the proportion of English in the lyrics is high as well. There has also been an increase in the number of songs having only English lyrics. In addition, there are many songs whose lyrics have been changed to Japanese to promote them in Japan. Some netizens had a positive attitude toward foreign language lyrics and stated that they were aware that K-pop was expanding overseas and catering to fans worldwide; therefore, the use of foreign language lyrics was understandable. Furthermore, they stated that such lyrics were good because they provided a different feeling. However, negative attitudes were stronger because many felt that the lyrics of K-pop songs that used large amounts of English were not easily comprehensible, blurred the identity of K-pop, and lowered the quality of the songs. The researchers believe that having Korean lyrics is the minimum requirement for K-pop, and when K-pop maintains its identity and receives love worldwide, the Korean and Hangul that support it will also receive global attention.

PURPOSES : The purpose of this study is to provide basic data to improve the service life of asphalt pavement using basalt aggregate in Jeju Island by evaluating the performance of asphalt pavement through analysis of material and structural aspects. METHODS : To evaluate the performance of Jeju Island's asphalt pavement, cracks, permanent deformation, and longitudinal roughness were analyzed for the Aejo-ro road, which has high traffic and frequent premature damage. Cores were collected from Aejo-ro sections in good condition and damaged condition, and the physical properties of each layer were compared and analyzed. In addition, plate cores were collected from two sections with severe damage and the cause of pavement damage was analyzed in detail. RESULTS : About 45% of the collected cores suffered damage such as layer separation and damage to the lower layer. The asphalt content of surface layer in the damaged section was found to be 1.1% lower on average than that in the good condition section, and the mix gradations generally satisfied the standards. The density difference between the cores of each layer was found to be quite large, and the air voids was found to be at a high level. CONCLUSIONS : Test results on the cores showed that, considering the high absorption ratio of basalt aggregate, the asphalt content was generally low, and the high air voids of the pavement was believed to have had a significant impact on damage. High air voids in asphalt pavement can be caused by poor mixture itself, poor construction management, or a combination of the two factors. Additionally, the separation of each layer is believed to be the cause of premature failure of asphalt pavement.

PURPOSES : In this study, heating concrete is developed using heating artificial binder, which is more conductive and less expensive than ordinary Portland cement, and the heating effect is verified through laboratory tests and numerical analysis. METHODS : Based on the test results, the range of heat influence of the Heating concrete is calculated through numerical analysis. As a result of the laboratory test, the temperature rises to 58℃ after 10 minutes when heat generation started at the outdoor temperature of 12℃ and the initial temperature of the concrete specimen of 19.1℃. RESULTS : The heating effect is up to 50 cm in width and 90 cm in height centered on the heating concrete through numerical analysis to analyze the influence range of the Heating concrete based on the laboratory test results. However, when the distance from the heating concrete is greater than about 20 cm, the influence becomes very small, and the rate of temperature decrease drops significantly. CONCLUSIONS : From the test and numerical analysis, it can be used as an eco-friendly heating material suitable for concrete pavements.

본 연구는 언어의 공공성과 전문성에 대한 문제의식에서 기획되었다. 이를 위해 전문 영역인 유전자변형생물체[LMO] 관련 공공기관 홈페이지 를 비교 분석하여 공공언어 사용 실태를 파악하였다. 그 결과 다음과 같 은 시사점을 이끌어 낼 수 있었다. 장르적 측면에서 LMO 홈페이지들은 ‘안내문’의 특성을 보이며, 주제어를 홈페이지 화면 전면에 제시하여 공공 언어의 수용성과 접근성을 제고하였다. 다음으로 표기의 정확성 측면에 서 전문 용어 및 법령, 관련 규정, 약어(略語) 표기의 통일성과 일관성 확보가 필요하다는 것을 확인하였다. 소통성 측면에서는 LMO와 GMO의 개념 정의 및 설명 방식에 통일성과 일관성을 확보하여 전문 용어의 이 해도를 높일 것을 제안하였다. 또한 각 기관 홈페이지가 비교적 생산 목 적에 맞게 정보를 제공하고 있지만 기관 업무 특성에 따른 접근성과 편 의성 확보의 필요성을 강조하였다. 소통성을 강화하기 위해 관계기관 협 의에서 ‘공공언어적인 관점 반영’을 안건으로 선정할 것을 제언한다.

Park, Eunha. (2023). “Analysis of Language Use and Characteristics of Korean Bestseller Book Titles over the Past Five Years”. The Sociolinguistic Journal of Korea, 31(4), 175-201. This study analyzed linguistic composition of titles of recent best-selling books in online bookstores over the past five years. Additionally, we sought to understand the characteristics and social aspects of the words appearing in the book. The results of the analysis of the composition of book names show that the number of book titles written in Hangul or with Hangul and numbers was the most common over the past five years. In terms of length, the book titles were most frequently between four and eight syllables long. The most frequent names utilized nouns or noun phrases, followed by full sentences, and the plain-type Haerache ranked third. As a result of analyzing the words in the title of the books, when the title of the book over the past five years was displayed in Wordcloud, the words in the TOEIC test books and the title of the comic books were visualized in large format. As a result of examining the frequency of words in Boyant-tool, the number of numbers(1, 2) that did not appear in Wordcloud was the highest, followed by words from TOEIC test books and comic books.

algorithms for deriving and analyzing retroreflectivity influence factors through regression analysis. METHODS : An experimental road lane was created to examine the trends of retroreflectivity and LiDAR intensity values, and a controlled indoor experiment was conducted to identify influencing factors. The optimal algorithm was developed by regression analysis of the experimental data. RESULTS : The significance probability (P-value) through SPSS linear regression analysis was 0.000 for measured height, 0.001 for perpendicular angle, 0.157 for vertical angle, and 0.000 for LiDAR intensity, indicating that measured height, vertical angle, and LiDAR intensity are significant factors because the significance probability is less than 0.05, and vertical angle is not significant. The NNR regression model performed the best, so the measurement data with height (1.2m, 2m, 2.2m) and vertical angle (11.3°, 12.3°, 13.5°) were analyzed to derive the optimal LiDAR Intensity measurement height and vertical angle. CONCLUSIONS : For each LiDAR measurement height and vertical angle, the highest correlation between LiDAR Intensity and retroreflectivity was found at a measurement height of 1.2 meters and a vertical angle of 12.3°, where the model learning accuracy (R2) was the highest.

PURPOSES : The purpose of this study is to statistically analyze the meteorological factors that contribute to the formation of road surface icing based on actual cases of icing accidents and provide directions for improving icing evaluation criteria. METHODS : In this study, we collected cases of domestic road icing accidents by searching news articles with the keyword ‘icing collision accidents’. Subsequently, we determined the latitude, longitude, and altitude of accident locations using satellite map service. We applied the Inverse Distance Weighting (IDW) method and temperature lapse rate to estimate meteorological data at each location. Finally, statistical analysis was conducted for temperature, humidity, and precipitation occurrence using probability density functions. RESULTS : As a result, road icing accident data points with identifiable location coordinates were collected. Among these, temperature, humidity, and precipitation occurrence from Automated Weather Stations (AWS) data were selected for analysis. During the process of correcting meteorological factors using the Inverse Distance Weighting (IDW) method, the optimal Weighting Exponent (p) that minimizes the error was determined and applied. The results showed that accidents occurring in the morning indicated the highest accident occurrence rate. The average temperature at the time of the accidents was -1.4°C, with a humidity level of 85.1%. Precipitation was observed at the time of the accident in 19 cases. CONCLUSIONS : Icing on pavement can occur not only under extreme weather conditions but also under typical meteorological conditions. Typically, icing can occur when the relative humidity is above 70%. Accordingly, for future improvements in the evaluation criteria for icing-prone areas by the Ministry of Land, Infrastructure and Transport, it is possible to incorporate the temperature and humidity ranges that generally lead to icing, taking into account climate characteristics.

현재 주요 수목병해 방제는 육안조사 등을 기반으로 한 현장조사를 통해 실시 되고 있으나, 목적 달성에 있어 그 효율성 높지 않다. 수목병의 예찰 방법을 고도화하고 적기방제를 통해 그 피해를 저감시키기 위해, 본 연구는 메타지놈 분석을 이용하여 두릅나무에서의 곰팡이 다양성을 조사하였다. 속(Genus) 수준에서 메타지놈 분석결과 총 20개의 곰팡이 상이 해당 재배지 내 두릅나무에 분포하는 것으로 확인되었다. 그 중, Alternaria속과 Puccinia속이 우점하는 것으로 조사되었으며, 이는 두릅나무 재배지 내 전체에서 개체별로 일관되게 나타났으며, 특히 해당 재배지 내 두릅나무 녹병이 우점적으로 발생함이 확인되었다. 이러한 결과를 바탕으로 두릅나무에서의 주요 곰팡이 다양성에 대한 스크리닝과 함께 주요 또는 잠재적 수목병원균류를 대상으로 메타지놈 기법으로 확인할 수 있음을 본 연구결과를 통해 확인되었다.

본고는 표준 중국어 초급 학습자를 대상으로 ‘绕口令’ 자료를 활용하여 제3성과 제 2성에 중점을 둔 성조 교육 방안을 설계하고, 이를 직접 실제 교육 현장에 적용하여 그 효과를 검증하는 것에 그 목적을 두고 있다. 이를 위해 2장에서는 수업 설계 방 안을 제시하였고, 3장에서는 수업의 구체적인 운영 및 결과, 만족도에 대한 분석을 진행하였으며, 마지막 4장에서는 본고의 연구 성과를 종합하였다.

한반도를 포함하는 동아시아 지역에 영향을 미치거나 피해를 발생시킬 수 있는 화산으로는 일본 화산과 백두산을 포함하여 중국의 동부지역에 위치한 수 개의 활화산은 물론 거리는 3,000km 정도 떨어져 있으나 한반도 주변의 항공 운항에 결정적인 영향을 미칠 수 있는 활화산이 러시아의 캄차카반도에도 다수 분포되어 있다. 이에 본 연구에서는 2005년~2013년 기간의 기상 자료를 기반으 로 주요 화산의 가상 분화 시나리오에 의해 수행된 화산재 확산 해석 결과를 이용하여 화산재의 한반도 영향 가능성을 확률적으로 분 석하였다. 그 결과 백두산과 아소산의 경우 화산폭발지수 7로 분화하는 경우, 7월에서 9월에 분화하는 경우 한반도 전역에 영향을 미 칠 가능성이 가장 클 것으로 분석되었으며, 울릉도도 유사한 기간에 분화하는 경우 영향의 가능성이 상대적으로 높을 것으로 분석되 었다, 이는 여름철에 나타나는 동아시아 지역 주변의 압력 배치 때문으로 파악되었다.

이 연구는 식품제조업과 음료제조업에 속한 1,045개의 기업에 대한 재무제표 패널자료를 이용하여 한계기업으로의 전락에 영향을 주는 요인을 분석하였다. 한계기업의 식별 기준으로 이자보상배율이 3년 연속 1보다 작을 경우를 선택하였다. 패널 프로빗 모형의 추정 결과에 따르면, 개별 기업의 성장성 하락은 한계기업으로 전락할 확률을 높이는 반면, 수익성이나 활동성 지표의 상승은 한계기업으로 전락할 확률을 유의미하게 낮추는 것으로 분석되었다. 또한 타인자본 비중이 늘어나거나 또는 차입금의존도가 높은 기업일수록, 한계기업으로 전락할 확률이 높았다. 기업의 유동성 또한 한계기업으로의 전락 확률에 유의미한 영향을 주었다. 기업 규모도 한계기업 여부와 연관되었는데, 소기업이 대기업에 비해 한계기업으로 전락할 확률이 상대적으로 높았다.

PURPOSES : This study is aimed to economic analysis of the ferronickel slag pavement method carried out to suggest the necessity of developing ferronickel slag pavement technology. METHODS : A life cycle cost analysis of the application of the Ferronickel Slag pavement method and the cutting + overlay pavement method was performed to compare the economic indicators and greenhouse gas emissions for each pavement method. RESULTS : As a result of the analysis, regardless of the Ferronickel Slag mixing rate, if the common performance of the Ferronickel Slag pavement method is the same or superior to the existing pavement method, it is more economical than the existing pavement method. Furthermore, the lower the maintenance cost of the Ferronickel Slag pavement method, the higher the economic feasibility due to the high Ferronickel Slag mixing rate. Greenhouse gas emissions can be reduced from at least 9% to up to 53% through the application of the Ferronickel Slag pavement method, except for some scenario analysis results. CONCLUSIONS : This study provided that the Ferronickel Slag pavement method was superior to the existing pavement method in terms of economic and environmental aspects. Therefore, it was found that the objective justification of developing road pavement technology using Ferronickel Slag was secured.

This study investigates the integration of astronomy-related topics in the Korean national science curricula spanning from 1945 to 2023. We analyze the placement and extent of astronomy content across different school levels. Astronomy contents in the science curricula have changed in response to social needs (e.g., practical knowledge required for agriculture and fishery) and advancement in astronomical research (e.g., the discovery of exoplanets and the suggestion of new cosmological parameters). Contents addressing the motions of celestial objects and stellar physical properties have remained relatively consistent. In the latest 2022 revised national curriculum, scheduled for implementation in 2024, several elements, such as coordinate systems, have been removed, while the inquiry activities using digital tools are emphasized. The incorporation of the cosmic perspectives in the national curriculum, as well as astronomy education within the context of education for sustainable development, remains limited even in the most recent curriculum. For future life revisions, the active participation of researchers is needed to reflect the latest astronomical research progress and scientific characteristics in the field of astronomy.