• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.159-159
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• 2022

Soil represents a substantial component within the global carbon cycle and small changes in the SOC stock may result in large changes of atmospheric CO₂ particularly over tens to hundreds of years. In this study, we aim to (i) evaluate the SOC stock in the topsoil 0 - 15 cm from soil physical and chemical characteristics and (ii) find the correlation of SOC and soil organic matter (SOM) for national-scale in South Korea. First of all, based on the characteristics of the soil to calculate the soil hydraulic properties, SOC stock is the SOC mass per unit area for a given depth. It depends on bulk density (BD-g/cm³), SOC content (%), the depth of topsoil (cm), and gravel content (%). Due to insufficient data on BD observation, we establish a correlation between BD and SOC content, sand content, clay content parameter. Next, we present linear and non-linear regression models of BD and the interrelationship between SOC and SOM using a linear regression model and determine the conversion factor for them, comparing with Van Bemmelen 1890's factor value for the country scale. The results obtained, helps managers come up with suitable solutions to conserve land resources.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.167-167
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• 2023

Soil organic carbon (SOC) is a critical component of soil health and is crucial in mitigating climate change by sequestering carbon from the atmosphere. Accurate estimation of SOC storage is essential for understanding SOC dynamics and developing effective soil management strategies. This study aimed to investigate the factors influencing the spatial distribution of SOC storage in South Korea, using bulk density (BD) prediction to estimate SOC stock. The study utilized data from 393 soil series collected from various land uses across South Korea established by Korea Rural Development Administration from 1968-1999. The samples were analyzed for soil properties such as soil texture, pH, and BD, and SOC stock was estimated using a predictive model based on BD. The average SOC stock in South Korea at 30 cm topsoil was 49.1 Mg/ha. The study results revealed that soil texture and land use were the most significant factors influencing the spatial distribution of SOC storage in South Korea. Forested areas had significantly higher SOC storage than other land use types. Climate variables such as temperature and precipitation had a relative influence on SOC storage. The findings of this study provide valuable insights into the factors influencing the spatial distribution of SOC storage in South Korea.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.38-43
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• 2008

한 국가의 SOC 시설 보유량은 공공서비스의 공급능력을 보여주는 지표로 활용되고 있으며, 국가경쟁력의 원천이 되고 있다. 한국은 SOC 시설이 충분하다는 판단하에 '03년 이후 SOC 투자를 점차 축소하고 있다. 하지만 SOC 투자 축소는 기존 SOC 공사의 공기지연이 발생하고 있으며, 향후에는 국가경쟁력을 저해할 가능성을 갖고 있다. 따라서 충분한 수준의 SOC 투자는 지속되어야 한다. 이를 위해 우선 교통시설특별회계를 최소한 국가기간교통망계획의 계획기간인 '19년까지 연장할 필요가 있다. 또한 민간투자사업을 효과적으로 활용하고, SOC 투자를 완공위주의 집중투자를 해야 한다.

• 한국토양비료학회지
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• 제47권3호
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• pp.205-212
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• 2014

Chronological changes of soil organic carbon (SOC) must be prepared by IPCC guidelines for national greenhouse gas inventories. IPCC suggested default reference SOC stocks for mineral soils and relative stock factors for different management activities where country own factors were not prepared. 3.4 million data were downloaded from agricultural soil information system and analyzed to get chronological changes of SOC for some counties and for land use in Korea. SOC content of orchard soil was higher than the other soils but chronological SOC changes of all land use had no tendency in differences with high standard deviation. SOC contents of counties depended on their own management activities and chronological SOC changes of districts also had no tendency in differences. Thus, Korea should survey the official records and relative stock factors on management activities such as land use, tillage and input of organic matter to calculate SOC stocks correctly. Otherwise, Korea should establish a model for predicting SOC by analyzing selected representative fields and by calculating SOC differences from comparing management activities of lands with those of representative fields.

• 한국작물학회지
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• 제68권2호
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• pp.90-96
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• 2023

본 연구는 볏짚퇴비의 사용량(7.5, 15, 22.5, 30 ton ha^-1)이 토양 화학성 및 유기탄소 축적에 미치는 영향을 알아보고자 하였다. 연구결과 NPKC7.5 처리구에서 SOC와 SOC stock이 각각 15.3 g kg^-1, 57.8 Mg C ha^-1으로 NPKC22.5와 NPKC30 처리구보다 낮았으며, 볏짚퇴비 사용량이 가장 많았던 NPKC30 처리구는 SOC가 22.8 g kg^-1, SOC stock이 71.2 Mg C ha^-1로 NPKC 22.5처리구와 유의한 차이를 보이지 않았으나 처리구 중 높은 경향을 보여 퇴비 사용량이 많을수록 SOC의 축적이 많아진다는 것을 알 수 있었다. 그러나 교환성 칼륨과 칼슘이 퇴비 사용량이 늘어날수록 높아져 NPKC22.5와 NPKC30 처리구는 적정범위를 초과하였다. 과도한 유기물원 투입은 토양유기탄소 축적을 증가시키더라도 작물에 흡수되지 못한 양분이 수계로 유출되어 수질을 오염시키거나 토양에 축적되어 토양 환경에 악영향을 미칠 수 있으므로 지속적으로 볏짚퇴비를 투입하기 위해서는 토양, 수질 등 농업 환경을 고려하여 표준사용량을 사용하는 것이 적절할 것으로 판단된다.

• 대한교통학회지
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• 제23권2호
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• pp.83-92
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• 2005

OECD 국가들 중 국토계수가 우리나라의 50%(1/2)~200%(2배)인 4개국의 1인당 GDP 10,000달러 도달시기의 국토계수당 도로보급률을 비교하면, 우리나라의 유효도록보급률은 평지대비 약 58.9% 수준, 총면적대비 약 63.4% 수준인 것으로 분석되었다. 철도도 동일한 방법으로 우리나라의 철도스톡규모가 이들 국가의 평지 면적 대비 약 41.3%, 전체 면적 대비 약 53.2% 수준으로 분석되었다. 또한 이들 나라의 평균 유효도로연정과 유효철도연장을 목표 도로 및 철도스톡으로 정의하고 목표스톡에 도달하기 위한 각년도 목표주자금액을 산정하였는데, 2000년 실질가격 기준으로 도로와 철도는 매년 약 15조 2천억 원 및 약 6조 5천억 원을 투자하여야 하는 것으로 분석되었다. 이를 실제 투자금액과 비교하면 철도는 실제 투자금액이 목표투자금액에 미달하여 향후 철도투자를 증가시킬 필요성이 제기되었다.

• 산업경영시스템학회지
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• 제41권2호
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• pp.153-158
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• 2018

At the Bank of Korea, capital stock statistics were created by the PIM (perpetual inventory method) with fixed capital formation data. Asset classifications also included 2 categories in residential buildings, 4 non-residential buildings, 14 constructions, 9 transportation equipment, 28 machinery, and 2 intangible fixed assets. It is the Korean government accounting system which is developed much with the field of the national accounts including the valuation, but until 2008 it was consistent with single-entry bookkeeping. Many countries, including Korea, were single-entry bookkeeping, not double-entry bookkeeping which can be aggregated by government accounting standard account. There was no distinction in journaling between revenue and capital expenditure when it was consistent with single-entry bookkeeping. For example, we would like to appropriately divide the past budget accounts and the settlement accounts data that have been spent on dredging into capital expenditure and revenue expenditure. It, then, tries to add the capital expenditure calculated to FCF (fixed capital formation), because revenue expenditure is cost for maintenance etc. This could be a new direction, especially, in the estimation of capital stock by the perpetual inventory method for infrastructure (SOC, social overhead capital). It should also be noted that there are differences not only between capital and income expenditure but also by other factors. How long will this difference be covered by the difference between the 'new series' and 'old series' methodologies? In addition, there is no large difference between two series by the major asset classification level. If this is treated as a round-off error, this is a problem.

• The Journal of Asian Finance, Economics and Business
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• 제8권12호
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• pp.233-239
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• 2021

The objective of this study is to find out the factors affecting the employees' loyalty in private joint-stock commercial banks in Mekong Delta, Vietnam. Then, possible solutions can be proposed, which can be implemented to improve employees' engagement in private joint-stock commercial banks in Mekong Delta, Vietnam, in the future. The author conducted a survey of 300 employees at 6 private joint-stock commercial banks in 6 provinces in Mekong Delta: An Giang, Tra Vinh, Can Tho, Ben Tre, Soc Trang, and Tien Giang. The author also used the Cronbach Alpha reliability analysis method, exploratory factor analysis (EFA), and multivariate regression analysis. The results show the degree of influence of factors on employees' loyalty - according to decreasing importance: Income, Job characteristics, Working environment, Colleagues, Leadership. The authors propose some solutions based on the research findings, including focusing on assigning the right employees to the right jobs, creating a competitive and fair working environment, focusing on a reasonable income policy, and transparency in working relationships to help bank managers in the Mekong Delta, Vietnam improve human resource management to improve employee loyalty to private joint-stock commercial banks in Vietnam.

• Journal of Ecology and Environment
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• 제43권1호
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• pp.43-60
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• 2019

Background: Tropical montane forests played an important role in the provision of ecosystem services. The intense degradation and deforestation for the need of agricultural land expansion result in a significant decline of forest cover. However, the expansion of agricultural land did not completely destruct natural forests. There remain forests inaccessible for agricultural and grazing purpose. Studies on these forests remained scant, motivating to investigate biomass and soil carbon stocks. Data of biomass and soils were collected in 80 quadrats ($400m^2$) systematically in 5 forests. Biomass and disturbance gradients were determined using allometric equation and disturbance index, respectively. The regression modeling is employed to explore the spatial distribution of carbon stock along disturbance and environmental gradients. Correlation analysis is also employed to identify the relation between site factors and carbon stocks. Results: The result revealed that a total of 1655 individuals with a diameter of ${\geq}5cm$, representing 38 species, were measured in 5 forests. The mean aboveground biomass carbon stocks (AGB CS) and soil organic carbon (SOC) stocks at 5 forests were $191.6{\pm}19.7$ and $149.32{\pm}6.8Mg\;C\;ha^{-1}$, respectively. The AGB CS exhibited significant (P < 0.05) positive correlation with SOC and total nitrogen (TN) stocks, reflecting that biomass seems to be a general predictor of SOCs. AGB CS between highly and least-disturbed forests was significantly different (P < 0.05). This disturbance level equates to a decrease in AGB CS of 36.8% in the highly disturbed compared with the least-disturbed forest. In all forests, dominant species sequestrated more than 58% of carbon. The AGB CS in response to elevation and disturbance index and SOC stocks in response to soil pH attained unimodal pattern. The stand structures, such as canopy cover and basal area, had significant positive relation with AGB CS. Conclusions: Study results confirmed that carbon stocks of studied forests were comparable to carbon stocks of protected forests. The biotic, edaphic, topographic, and disturbance factors played a significant variation in carbon stocks of forests. Further study should be conducted to quantify carbon stocks of herbaceous, litter, and soil microbes to account the role of the whole forest ecosystem.

• 한국전자통신학회논문지
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• 제10권8호
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• pp.851-860
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• 2015

교통부문 사회간접자본(SOC)은 국가 전체의 경제활동에 필요한 기반을 제공하는 공공시설이며 도로, 철도, 지하철, 항만 등으로 구분된다. 또한 국가의 생산성 및 경쟁력 증대를 위해서는 주요 사회간접자본(도로, 철도, 항만 등)을 적기 적소에 공급하는 것이 중요하다. 본 연구에서는 철도를 포함한 SOC스톡의 확충 필요성을 인지하고 국가경쟁력(생산성)증대에 미치는 영향 정도를 파악하기 위해 국가별 사회경제 및 수송지표간 상관분석, 요인분석을 수행하였다. 그 결과 GDP는 인구, 국토면적, 유효철도연장, 도로연장과 높은 상관성(0.59~0.99)을 보였다. 특히 러시아의 도시교통시스템 현황을 분석하고 주요 OECD국가의 인구, GDP, 국토면적 등 사회경제지표와 도로 및 철도연장 등 사회간접자본(SOC)을 비교하여 장래 교통시설투자 확충의 필요성과 이에 따른 국가 경쟁력 변화를 분석한 결과, 경전철 신설 개통은 유효철도연장 증가 및 이에 따른 GDP 증가에 많은 영향을 미치는 것으로 분석되었으며, 고속 트램(경전철)의 추가 개통을 가정하여 유효철도 연장이 2014년에 비해 10% 증가함을 가정 할 경우 GDP는 21.6% 증가할 것으로 분석되었다.