ASL estimation of public building is based on how appropriate the maximum age of the asset is derived based on the age record of the asset in the statistical data owned by public institutions. This is because we get a 'constrained' ASL by that number. And it is especially true because other studies have assumed that the building is an Iowa curve R3. Also, in this study, the survival rate is 1% as the threshold value at which the survival curve and the predictable life curve almost coincide. Rather than a theoretical basis, in the national statistical survey, the value of residual assets was recognized from the net value of 10% of the acquisition value when the average service life has elapsed, and 1% when doubling the average service life has elapsed. It is based on the setting mentioned above. The biggest constraint in fitting statistical data to the Iowa curve is that the maximum ASL is selected at R3 150%, and the 'constrained' ASL is calculated by the proportional expression on the assumption that the Iowa curve is followed. In like manner constraints were considered. First, the R3 disposal curve for the RCC(reinforced cement concrete) building was prepared according to the discarding method in the 2000 work, and it was jointly worked on with the National Statistical Office to secure the maximum amount of vintage data, but the lacking of sample size must be acknowledged. Even after that, the National Statistical Office and the Bank of Korea have been working on estimating the Iowa curve for each asset class in the I-O table. Another limitation is that the asset classification uses the broad classification of buildings as a subcategory. Second, if there were such assets with a lifespan of 115 years that were acquired in 1905 and disposed of in 2020, these discarded data would be omitted from this ASL calculation. Third, it is difficult to estimate the correct Iowa curve based on the stub-curve even if there is disposal data because Korea has a relatively shorter construction history, accumulated economic wealth since the 1980’s. In other words, “constrained” ASL is an under-estimation of its ASL. Considering the fact that Korea was an economically developing country in the past and during rapid economic development, environmental factors such as asset accumulation and economic ability should be considered. Korea has a short period of accumulation of economic wealth, and the history of 'proper' architectures faithful to building regulations and principles is short and as a result, buildings 'not built properly' and 'proper' architectures are mixed. In this study, ASL of RCC public building was estimated at 70 years.

With rapid urbanization, the importance of urban warfare is increasing, and it is also required to reflect the characteristics of cities in wargame models. However, in the military's wargame models, the urbanization factor was calculated and used without theoretical basis. In this study, we investigate techniques for estimating the urbanization factor using Fractal dimension theory. The urbanization factor we propose can suggest a logical and valid representative value when used in conjunction with Agent Based Model and other methodologies.

The 2017 Pohang earthquake afflicted more significant economic losses than the 2016 Gyeongju earthquake, even if these earthquakes had a similar moment magnitude. This phenomenon could be due to local site conditions that amplify ground motions. Local site effects could be estimated from methods using the horizontal-to-vertical spectral ratio, standard spectral ratio, and the generalized inversion technique. Since the generalized inversion method could estimate the site effect effectively, this study modeled the site effects in the Korean peninsula using the generalized inversion technique and the Fourier amplitude spectrum of ground motions. To validate the method, the site effects estimated for seismic stations were tested using recorded ground motions, and a ground motion prediction equation was developed without considering site effects.

본 연구는 국립산림과학원 용인시험림 내 대왕참나무 조림지를 대상으로 총 77본의 표준목을 벌채하여 수간고별 직경과 수간석해 데이터를 이용하여 간곡선 모형을 추정하고자 하였다. 모델의 적합성을 판단하기 위해 적합도 지수(Fitness Index), 평균제곱근오차(Root Mean Square Error), 추정의 표준오차(Standard Error of Estimate), 평균편차(Mean Difference), 절대평균편차(Absolute Mean Difference), 아카이케 정보 기준(AIC), 아케이케 정보 기준 가중치(AICw)를 이용했으며, 최종적으로 Ranking method 방법을 통해 가장 적합한 모델을 선발하였다. 수간곡선식 을 추정하기 위하여 총 세 가지 모델이 이용되었으며, 자료 중에서 80%의 자료는 모델 개발에 활용되었고 나머지 20%는 모델의 타당성 검정을 위해 사용되었다. 본 연구에서 제시된 수간곡선식의 추정된 파라미터는 100% 자료를 이용하였다. 본 연구의 결과, 중부지방 대왕참나무는 Kozak88 모델이 가장 적합한 식으로 평가되었다.

본 논문에서는 구조물의 부분 변위값으로 전체 구조물의 변위 형상을 예측할 수 있는 인공지능 학습기법을 개발하였으며, 개발된 기술의 성능을 실험을 통해 평가하였다. 3차원 공간에서 변위 형상 및 노드 위치 좌표의 특성을 학습에 반영할 수 있는 Image-to-Image 변위 형상 학습과 위치 특징을 결합한 변위 상관 학습 방법을 제시하였다. 개발된 인공지능 학습방법의 성능을 평가하기 위해 목업 구 조 실험을 진행하였고, 3D 스캔으로 측정한 변위값과 인공지능으로 예측한 결과를 비교하였다. 비교 결과 인공지능 예측 결과는 3D 스캔 측정 결과에 비해 5.6~5.9%의 오차율을 보여 적정 성능을 보였다.

The objective of this study is to estimate the dietary exposure of polychlorinated dibenzo-p-dioxins and dibezofurans (PCDD/Fs) of Korean population via milk and meat using a probabilistic exposure assessment model. Total 319 raw milk and meat samples collected in the period 2006-2008 from nationwide Korea were measured the concentrations of 17 PCDD/Fs. Distributions of dietary exposure of 7 age subgroups to PCDD/Fs from the commodities were estimated probabilistically using Monte Carlo simulations. Dietary exposure groups were divided as lower, medium and high consumer subgroups according to the consumption of each commodity. The amounts of dietary exposures of Korean population subgroups were compared to the provisional maximum tolerable monthly intake (PTMI) recommended by the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (JECFA). The mean PCDD/Fs concentrations in raw milk and meat of beef, prok and chicken were measured as 0.501, and 0.022~0.150pg WHO-TEQ/g, respectively. Dietary exposure of children was significantly higher than that of adults due to their high milk consumption per body weight (BW). Dietary intake of PCDD/Fs of the Korean populations estimated ranged from 0.154 to 1.248 pg WHO- TEQ/kg BW/day for high consumers (the 97.5th percentile) at the upper bound. Dietary intakes of average population of various subgroups were below the half of PTMI, but those of higher consumers were found exceeding or comparable to PTMI at the upper bound level. This study also suggests that the estimated PCDD/Fs concentrations in milk and meat are comparable to those reported in previous studies. Probabilistic assessment model for PCDD/Fs exposure in meat and milk commodities could be used to estimate the exposure of PCDD/Fs in Korean population for the development of risk mangement mesaures for PCDD/Fs in meat and milk.

Welding is one of representative manufacturing processes in the industrial field. Cryogenic storage containers are also manufactured through welding, and conversion to laser welding is issue in the field due to many advantages. Since welding causes thermal-elastic deformation, design considering distortion is required. Prediction of distortion through FEM is essential, but laser welding has difficulties in the field because there is no representative heat source model. The author presented the model that can cover various models using a multi-layer heat source model in previous studies. However the previous study has a limitation which is a welding heat source model must be derived after performing bead on plate welding. Thus this study was attempted to estimate the welding heat source parameters by comparing the shape of bead under various conditions. First, the difference between penetration shape and welding heat source parameters according to welding power was analyzed. The radius of the welding heat source increased according to the welding power, and the depth of the welding heat source also increased. The correlation between the penetration shape and the welding heat source parameter appears at a similar rate, however the follow-up research is necessary with more model data.

2000년 이후 급격한 생활환경의 변화와 근래에 발생한 예측 불가능한 전염병 등의 영향으로 국내․외의 여행과 이동을 자제하고 건강을 위한 야외활동은 기존에 조성되어 온 유명한 둘레길, 숲길 등의 공익적 가치가 더욱 중요하게 부각되고 있다. 본 연구는 CVM을 활용하여 충청도와 경상도를 가로지르는 숲길을 연결하는 가칭 ‘동서트레일’에 대한 환경적 가치를 추정하였다. 연구는 동서트레일을 방문한 탐방객을 대상으로 하였으며, 723부를 분석에 이용하였다. 조사대상지 를 방문한 응답자의 기본적인 이용행태는 주 2-3회 정도 운동하는 건강에 관심이 많은 사람들이며, 거주지에서 멀지 않은 곳의 숲길을 친구나 가족들과 방문하고, 1회 방문 시 약 5만원 이상을 소비하는 경향을 보이고 있다. 둘레길을 방문할 때 숲길코스에 대한 안내판이 부족하다는 것을 느끼고 있으며, 적절한 장소에 쉼터를 설치해 주기를 원하는 것으로 나타났다. 동서트레일의 보존가치를 추정하기 위한 방법은 Hanemann식 이중경계 로짓모형을 이용하였다. 동서트레일 방문자가 1회 방문 시 얻을 수 있는 환경적 가치는 30,087원으로 추정할 수 있었다. 추정된 금액을 동서트레 일 인근 직접이용권에 속한 인구로 환산하면 동서트레일의 연간 환경가치는 약 940억원으로 추정할 수 있다. CVM을 이용한 숲길에 대한 환경의 가치추정에 대한 연구는 현재까지 진행된 적이 없으며, 추정된 연구 결과는 국가 숲길 정책에 대한 타당성을 제시해 줄 수 있을 것이다.

The “Carbon Neutral” has become the most important goal to achieve in the era of the climate change crisis. K-water has prepared a roadmap for implementing “Carbon Neutral” by 2050. However, only the reduction targets and strategies for scope 1 and 2 have been set, so the management of carbon generated during the construction project and upfront carbon is not being implemented. Therefore, in this study, the criteria and methodology for estimation carbon emissions in the construction sector at domestic and foreign were reviewed, and a methodology for estimation carbon emissions suitable for K-water construction projects was presented, and a case study was conducted. As a result, most of the carbon emissions were more than 90% of the upfront emissions due to material production. Therefore, upfront carbon management is required for carbon management of K-water construction projects, and it is necessary to quantify carbon emissions through GHG construction inventory, etc., and to establish strategies for future reduction technologies.

We deduced the proper estimation methodology for the amount of carbon sequestration by damaged trees for Environmental Impact Assessment (EIA). The nine development projects related to renewable energy, damaged trees occur, assessment status and used method of evaluating the carbon storage of damaged trees were summarized. And after re-calculating the carbon storage of damaged trees through allometric equations, the difference between the two groups, re-calculated the damaged trees carbon storage and the damaged trees carbon storage in the report, was validated. As a result, damaged trees carbon storage in words was more than the re-calculated damaged trees carbon storage, and it was statistically significant (p<0.005). This result means that the existing method for calculating damaged tree carbon storage is overcalculated. It was judged that it was necessary to improve the calculation method. Therefore, allometric equations suitable for each dominated-tree species should be used when calculating the damaged tree carbon storage. Furthermore, we propose to establish a carbon storage calculation system based on actual data from the ecosystem so that researchers can efficiently and accurately the damaged trees carbon storage. Key words: damaged vegetation, carbon sequestration, allometric equation, environmental impact

Many manufacturers applying third party logistics (3PLs) have some challenges to increase their logistics efficiency. This study introduces an effort to estimate the weight of the delivery trucks provided by 3PL providers, which allows the manufacturer to package and load products in trailers in advance to reduce delivery time. The accuracy of the weigh estimation is more important due to the total weight regulation. This study uses not only the data from the company but also many general prediction variables such as weather, oil prices and population of destinations. In addition, operational statistics variables are developed to indicate the availabilities of the trucks in a specific weight category for each 3PL provider. The prediction model using XGBoost regressor and permutation feature importance method provides highly acceptable performance with MAPE of 2.785% and shows the effectiveness of the developed operational statistics variables.

Purpose: In countries with a large elderly population, the integrated visiting health care program for the elderly in communities was effective in preventing frailty and reducing medical expenses. Customized preventive health service is essential in a super-aged society. The purpose of this study is to estimate the number of professionals who perform visiting health care for the elderly. Methods: The statistics for the elderly from Statistics Korea and the Visiting Healthcare Performance Report from Korea Health Promotion Institute were employed in the analysis. The elderly were divided into four groups: healthy, pre-frailty, frailty I, and frailty II, according to their health level. Through the focus group interview, the ratio of nurses, physical activity experts, and nutritionists was set at 8:1:1. Results: Three scenarios were classified into minimum, medium, and maximum according to the number of visits. In the case of Seoul, the number of essential professionals was calculated at least from 719 to a maximum of 1,837. Conclusion: Since this study has a limitation in calculating visiting health care experts only by the ratio of nurses, physical activity experts, and nutritionists, future studies should consider experts or professionals in the field of social welfare, oral health, and visiting treatment.

충생태 분야에서 생명표와 관련된 연구는 곤충연구자들에게 많은 관심을 받는 주제중 하나이다. 보통 두 가지 방법으로 생명표 통계량중 내적자연증가율을 추정하고 있는데, 첫 번째 하나는 순증가율(R 0 )에 자연로그를 취하고 평균세대기간(T )으로 나누어 근사치를 계산하는 방법이다(세대기간-기반 추정법). 다른 하나는 로트카-볼테라 개체군 생장 방정식에서 유도하여 최대우도법으로 정확한 내적자연증가율을 추정하는 방법이다(로트카-오일러식-기반 추정법). 후자의 경우 대상 집단의 초기 연령등급을 “0” 또는 “1”로 설정함에 따라 추정값에 차이가 발생하여 적용에 혼란이 제기되었다. 본 고찰에서는 생명표 통계량 계산과정의 역사를 간단히 정리하고, 로트카-오일러식-기반 추정법에서 최초 연령등급을 1로설정한 경우             의 형식, 반면 최초 연령등급을 0으로 설정한 경우     검색어: 생명표, 로트카-오일러식, 연령등급, 개체군 인구통계학, 안정 연령분포            의 형식을 적용해야 함을 재확인하였다.

Among the fishing vessels operating in the coastal waters, jigging fishing vessels were considered representative vessels engaged only by wind, sea, tide, and external force. Then, a fishing vessel with a length of shorter than 10 m from July 1, 2018 to August 5, 2019 was studied to obtain a drift prediction model by multiple regression analysis. In the correlation analysis between variables for leeway of speed and direction, the speed and direction of tidal seem to be the most affected in coastal waters. Therefore, it should be considered an explanatory variable when conducting drift tests. As a result of multiple regression analysis on the predicted equations of leeway speed and direction due to the external force on the drift of the fishing vessel, p < 0.000 was considered significant in the F-test, but the coefficient of determination was 55.2% and 37.8%. The effect on the predicted leeway speed was in the order of the tidal speed and current speed. In addition, the impact on the predicted leeway direction was in the order of the tidal speed and current speed.