• Title/Summary/Keyword: Long-Term Growth

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The Effect of Carbon Dioxide Leaked from Geological Storage Site on Soil Fertility: A Study on Artificial Leakage (지중 저장지로부터 누출된 이산화탄소가 토양 비옥도에 미치는 영향: 인위 누출 연구)

  • Baek, Seung Han;Lee, Sang-Woo;Lee, Woo-Chun;Yun, Seong-Taek;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.54 no.4
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    • pp.409-425
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    • 2021
  • Carbon dioxide has been known to be a typical greenhouse gas causing global warming, and a number of efforts have been proposed to reduce its concentration in the atmosphere. Among them, carbon dioxide capture and storage (CCS) has been taken into great account to accomplish the target reduction of carbon dioxide. In order to commercialize the CCS, its safety should be secured. In particular, if the stored carbon dioxide is leaked in the arable land, serious problems could come up in terms of crop growth. This study was conducted to investigate the effect of carbon dioxide leaked from storage sites on soil fertility. The leakage of carbon dioxide was simulated using the facility of its artificial injection into soils in the laboratory. Several soil chemical properties, such as pH, cation exchange capacity, electrical conductivity, the concentrations of exchangeable cations, nitrogen (N) (total-N, nitrate-N, and ammonia-N), phosphorus (P) (total-P and available-P), sulfur (S) (total-S and available-S), available-boron (B), and the contents of soil organic matter, were monitored as indicators of soil fertility during the period of artificial injection of carbon dioxide. Two kinds of soils, such as non-cultivated and cultivated soils, were compared in the artificial injection tests, and the latter included maize- and soybean-cultivated soils. The non-cultivated soil (NCS) was sandy soil of 42.6% porosity, the maize-cultivated soil (MCS) and soybean-cultivated soil (SCS) were loamy sand having 46.8% and 48.0% of porosities, respectively. The artificial injection facility had six columns: one was for the control without carbon dioxide injection, and the other five columns were used for the injections tests. Total injection periods for NCS and MCS/SCS were 60 and 70 days, respectively, and artificial rainfall events were simulated using one pore volume after the 12-day injection for the NCS and the 14-day injection for the MCS/SCS. After each rainfall event, the soil fertility indicators were measured for soil and leachate solution, and they were compared before and after the injection of carbon dioxide. The results indicate that the residual concentrations of exchangeable cations, total-N, total-P, the content of soil organic matter, and electrical conductivity were not likely to be affected by the injection of carbon dioxide. However, the residual concentrations of nitrate-N, ammonia-N, available-P, available-S, and available-B tended to decrease after the carbon dioxide injection, indicating that soil fertility might be reduced. Meanwhile, soil pH did not seem to be influenced due to the buffering capacity of soils, but it is speculated that a long-term leakage of carbon dioxide might bring about soil acidification.

Assessment of Region Specific Angstrom-Prescott Coefficients on Uncertainties of Crop Yield Estimates using CERES-Rice Model (작물모형 입력자료용 일사량 추정을 위한 지역 특이적 AP 계수 평가)

  • Young Sang, Joh;Jaemin, Jung;Shinwoo, Hyun;Kwang Soo, Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.256-266
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    • 2022
  • Empirical models including the Angstrom-Prescott (AP) model have been used to estimate solar radiation at sites, which would support a wide use of crop models. The objective of this study was to estimate two sets of solar radiation estimates using the AP coefficients derived for climate zone (APFrere) and specific site (APChoi), respectively. The daily solar radiation was estimated at 18 sites in Korea where long-term measurements of solar radiation were available. In the present study, daily solar radiation and sunshine duration were collected for the period from 2012 to 2021. Daily weather data including maximum and minimum temperatures and rainfall were also obtained to prepare input data to a process-based crop model, CERES-Rice model included in Decision Support System for Agrotechnology Transfer (DSSAT). It was found that the daily estimates of solar radiation using the climate zone specific coefficient, SFrere, had significantly less error than those using site-specific coefficients SChoi (p<0.05). The cumulative values of SFrere for the period from march to September also had less error at 55% of study sites than those of SChoi. Still, the use of SFrere and SChoi as inputs to the CERES-Rice model resulted in slight differences between the outcomes of crop growth simulations, which had no significant difference between these outputs. These results suggested that the AP coefficients for the temperate climate zone would be preferable for the estimation of solar radiation. This merits further evaluation studies to compare the AP model with other sophisticated approaches such as models based on satellite data.

The Economic Cycle and Contributing Factors to the Operating Profit Ratio of Korean Liner Shipping (경기순환과 우리나라 정기선 해운의 영업이익률 변동 요인)

  • Mok, Ick-soo;Ryoo, Dong-keun
    • Journal of Navigation and Port Research
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    • v.46 no.4
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    • pp.375-384
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    • 2022
  • The shipping industry is cyclically impacted by complex variables such as various economic indicators, social events, and supply and demand. The purpose of this study was to analyze the operating profit of 13 Korean liner companies over 30 years, including the financial crisis of the late 1990s, the global financial crisis of the late 2000s, and the COVID-19 global pandemic. This study was conducted to also identify factors that impacted the profit ratio of Korea's liner shipping companies according to economic conditions. It was divided into ocean-going and short-sea shipping, reflecting the characteristics of liner shipping companies, and was analyzed by hierarchical multiple regression analysis. The time series data are based on the Korean International Financial Reporting Standards (K-IFRS) and comprise seaborne trade volume, fleet evolution, and macroeconomic indicators. The outliers representing the economic downturn due to social events were separately analyzed. As a result of the analysis, the China Container Freight Index (CCFI) positively impacted ocean-going as well as short-sea liner shipping companies. However, the Korean container shipping volume only impacted ocean-going liners positively. Additionally, world and Korea's GDP, world seaborne trade volume, and fuel price are factored in the operating profit of short sea liner shipping. Also, the GDP growth rate of China, exchange rate, and interest rate did not significantly impact both groups. Notably, the operating profitability of Korea's liner shipping shows an exceptionally high rate during the recessions of 1998 and 2020. It is paradoxical, and not correlated with the classical economic indicators. Unlike other studies, this paper focused on the operating profit before financial expenses, considering the complexity as well as difficulty in forecasting the shipping cycle, and rendered conclusions using relatively long-term empirical analysis, including three economic shocks.

Evaluating the Capping Effects of Dredged Materials on the Contaminated Sediment for Remediation and Restoration of the West Sea-Byeong Dumping Site (서해병 폐기물 배출해역 오염퇴적물의 정화·복원을 위한 준설토 피복 효과 평가)

  • Kang, Dong Won;Lee, Kwang Sup;Kim, Young Ryun;Choi, Ki-young;Kim, Chang-joon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.2
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    • pp.212-223
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    • 2022
  • For the remediation and restoration of contaminated sediment at the West Sea-Byeong dumping site, dredged materials was dumped in 2013, 2014, 2016, and 2017. The physicochemical properties and benthic fauna in surface sediments of the capping area (5 stations) and natural recovery area (2 stations) were analyzed annually from 2014 to 2020 to evaluate the capping effect of the dredged materials. The natural recovery area had a finer sediment with a mean particle size of 5.91-7.64 Φ, while the sediment in the capping area consisted of coarse-grained particles with a mean particle size of 1.47-3.01 Φ owing to the capping effect of dredged materials. Considering that the contents of organic matters (COD, TOC, and TN) and heavy metals in the capping area are approximately 50 % lower (p<0.05) than that in the natural recovery area, it is judged that there is a capping effect of dredged materials. As a result of analyzing macrobenthic assemblages, the number of species and ecological indices of the capping area were significantly lower than that of the natural recovery area (p<0.05). The number of species and ecological indices at the capping area were increased for the first four years after the capping in 2013 and 2014 and then tended to decrease thereafter. It is presumed that opportunistic species, which have rapid growth and short lifetime, appeared dominantly during the initial phase of capping, and the additory capping in 2016 and 2017 caused re-disturbance in the habitat environment. In the natural recovery and capping areas, Azti's Marine Biotic Index (AMBI) was evaluated as a fine healthy status because it maintained the level of 2nd grades (Good), whereas Benthic Pollution Index (BPI) remained at the 1st and 2nd grade. Therefore, capping of dredged materials for remediation of contaminated sediment in the dumping site has the effect of reducing the pollution level. However, in terms of the benthic ecosystem, it is recommended that the recovery trend should be monitored long-term. Additionally, it is necessary to introduce an adaptive management strategy when expanding the project to remediate the contaminated sediment at the dumping area in the future.

Molecular and Phenotypic Characteristics of Patients with Pseudohypoparathyroidism: Single Center's Experience (가성부갑상선기능저하증 환자의 분자유전학적 및 임상적 특징: 단일기관의 경험)

  • Kim, Min-ji;Yoon, Ju Young;Yoo, Sukdong;Lee, Jun;Cheon, Chong Kun
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.21 no.1
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    • pp.7-14
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    • 2021
  • Purpose: Pseudohypoparathyroidism (PHP) is caused by genetic and epigenetic alteration in the GNAS locus, and characterized by the resistance to multiple hormones and the Albright's hereditary osteodystrophy (AHO) phenotype. This study investigated the phenotypic characteristics and molecular features of PHP. Methods: Eight patients who diagnosed as PHP were enrolled at Pusan National University Children's hospital and clinical features, biochemical and genetic findings were retrospectively reviewed. Results: Of a total of 8 patients, 5 were diagnosed with PHP1a, and 3 were diagnosed with PHP1b. Patients with PHP1a had three different mutations in the GNAS gene, and patients with PHPIb had imprinting defect in differentially methylated regions (DMRs) of the GNAS locus. Two novel GNAS variants were identified in patients with PHP1a, including c.313-2A>T and c.1094G>A. All patients with PHP1a displayed AHO features; short stature (80%), brachydactyly (80%), a round face (80%), obesity (40%), heterotopic ossification (60%), and intellectual disability (60%), whereas only one patient (33.3%) with PHP1b showed AHO feature such as a round face. When phenotypic features between PHP1a and PHP1b patients were compared, patients with PHP1b showed a tendency of higher current height standard deviation scores (SDS) compared to patients with PHP1a, (-3.2±2.1 vs.-1.1±0.8; P=0.06) Conclusions: This study summarizes the phenotypic and genetic features of the PHP patients. Although we found considerable clinical overlap between PHP1a and PHP1b, further long-term follow-up is needed to evaluate the growth and development of children with PHP, as well as the effects of end-organ resistances to endocrine hormones.

Analysis of Determinants of Carbon Emissions Considering the Electricity Trade Situation of Connected Countries and the Introduction of the Carbon Emission Trading System in Europe (유럽 내 탄소배출권거래제 도입에 따른 연결계통국가들의 전력교역 상황을 고려한 탄소배출량 결정요인분석)

  • Yoon, Kyungsoo;Hong, Won Jun
    • Environmental and Resource Economics Review
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    • v.31 no.2
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    • pp.165-204
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    • 2022
  • This study organized data from 2000 to 2014 for 20 grid-connected countries in Europe and analyzed the determinants of carbon emissions through the panel GLS method considering the problem of heteroscedasticity and autocorrelation. At the same time, the effect of introducing ETS was considered by dividing the sample period as of 2005 when the European emission trading system was introduced. Carbon emissions from individual countries were used as dependent variables, and proportion of generation by each source, power self-sufficiency ratio of neighboring countries, power production from resource-holding countries, concentration of power sources, total energy consumption per capita in the industrial sector, tax of electricity, net electricity export per capita, and size of national territory per capita. According to the estimation results, the proportion of nuclear power and renewable energy generation, concentration of power sources, and size of the national territory area per capita had a negative (-) effect on carbon emissions both before and after 2005. On the other hand, the proportion of coal power generation, the power supply and demand rate of neighboring countries, the power production of resource-holding countries, and the total energy consumption per capita in the industrial sector were found to have a positive (+) effect on carbon emissions. In addition, the proportion of gas generation had a negative (-) effect on carbon emissions, and tax of electricity were found to have a positive (+) effect. However, all of these were only significant before 2005. It was found that net electricity export per capita had a negative (-) effect on carbon emissions only after 2005. The results of this study suggest macroscopic strategies to reduce carbon emissions to green growth, suggesting mid- to long-term power mix optimization measures considering the electricity trade market and their role.

The Effect of Environmental Factors on Competency and Performance of Venture Companies: The Double Mediating Effect of Venture Firm Confirmation System Benefits and Venture Firm Internal Competencies (벤처기업에 대한 환경적 요소가 역량 및 성과에 미치는 영향: 벤처기업 확인제도 혜택과 벤처기업 내부 역량의 이중매개효과를 중심으로)

  • Park, Dain;Kim, Daejin
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.5
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    • pp.241-253
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    • 2023
  • In the current rapidly changing environment, each country continues to make efforts to create jobs and strengthen technological competitiveness. In particular, support and revitalization policies for venture companies and start-ups are known to play a role in increasing national competitiveness. Companies should make appropriate replacements amid growing uncertainties in the environment in which business life is shortened and customer needs are diversified due to intensifying competition. First of all, it is important for companies to make efforts to strengthen their internal capabilities on their own. However, venture companies lack internal resources and capabilities, so support from the external environment is important enough to lead to the survival of the company(Timmons, 1994). Financial support and certification systems are being operated at the national level to strengthen the competitiveness of companies. However, financial support can lower a company's self-sustainability depending on the situation, so non-financial support such as R&D support and start-up education is considered to be helpful in the long term for venture growth(Aghion et al., 2012; Jeon & Ko, 2021). Non-financial support is divided into commercialization, facilities, space, childcare, manpower, and certification systems, and this study confirmed the benefits of the venture company confirmation system, which is a certification system. To this end, the 2021 venture company precision survey data and venture company sales data were used, and analyzed using the SPSS 26.0 package and SPSS PROCESS MACRO. As a result of the analysis, it was confirmed that the level of the management environment of venture companies has a positive effect on the benefits of the venture confirmation system or increasing the level of venture company capabilities, but it is difficult to lead to actual management performance. In addition, it was confirmed that the level of venture company competency mediates the relationship between the level of the venture company's business environment and management performance. As a result, even if the level of the venture company's business environment is positive or venture-friendly, it can be said that companies with internal capabilities to digest support from the external environment increase management performance.

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The ecological response of the climate change indicator species, Korean fir (Abies koreana E. H. Wilson) (기후변화 지표종 구상나무(Abies koreana E. H. Wilson)의 생태학적 반응)

  • Yoon Seo Kim;Se Hee Kim;Jung Min Lee;Ji Won Park;Yeo Bin Park;Jae Hoon Park;Eui Joo Kim;Kyeong Mi Cho;Yoon Kyung Choi;Ji Hyun Seo;Joo Hyun Seo;Gyu Ri Kim;Ju Seon Lee;Do Hun Ryu;Min Sun Kim;Young Han You
    • Journal of Wetlands Research
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    • v.26 no.1
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    • pp.62-71
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    • 2024
  • To assess the ecological changes of Korean fir (Abies koreana E. H. Wilson) under climate change conditions, growth and physiological responses were analyzed over a 5-year period in a control group (outdoors) and in a treatment group where the temperature and CO2 levels were elevated to closely resemble RCP 4.5 conditions. The results showed an increasing trend in annual branch length of A.koreana in the climate change treatment group over time. While climate change conditions did not significantly impact the morphological differences of A.koreana leaves, they did influence the biomass of the leaves, suggesting that as climate change progresses, the productivity of A.koreana leaves may decline. On the other hand, the chlorophyll content in A.koreana under climate change conditions was higher in the climate change treatment group, whereas the photosynthesis rate, transpiration rate, water use efficiency and stomatal conductance was higher in the control group. This suggests that an environment with elevated temperature and CO2 could influence an increase in stomatal density, but having a negative impact on photosynthetic reactions. Further research on stomatal density under each environmental treatment will be required to confirm this hypothesis. Additionally, as this study only observed changes in leaf biomass, further empirical research should be considered to understand the changes in biomass of A.koreana under climate change conditions. In conclusion, the environmental adaptability of A.koreana is expected to weaken in the long term under elevated temperatures and CO2.

Effects of Co-digestate application on the Soil Properties, Leachate and Growth Responses of Paddy Rice (통합혐기소화액의 시용이 벼 생육 및 논토양 환경에 미치는 영향)

  • Hong, Seung-Gil;Shin, Joung-Du;Kwon, Soon-Ik;Park, Woo-Kyun;Lee, Deog-Bae;Kim, Jeong-Gyu
    • Journal of the Korea Organic Resources Recycling Association
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    • v.18 no.4
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    • pp.31-37
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    • 2010
  • Livestock manures have a potential to be a valuable resource with an efficient treatment. In Korea, 42 million tons of livestock manure were generated in 2008, and 84 % of them were used for compost and liquid fertilizer production. Recently recycling of livestock manure for biogas production through anaerobic digestion is increasing, but its utilization in agriculture is still uncertified. In this study, there was applied co-digestate to the paddy for rice cultivation based on N supplement. Co-digestate was fertilizer fermented with pig slurry and food waste combined with the ratio of 70:30(v:v) in its volumetric basis. For assessing the safety of co-digestate, it was monitored the contents of co-digestate for seasonal variation, resulted in no potential harm to the soil and plant by heavy metals. The results showed that soil applied with co-digestate was increased in exchangeable potassium, copper and zinc mainly due to the high rate of pig slurry in co-digestate applied. Considering high salt content due to the combination with food waste, strict quality assurances are needed for safe application to arable land though it has valuable fertilizer nutrient. Leachate after treatment showed that the concentration of nitrate nitrogen washed out within two weeks. Considering the salt accumulation results in soil, it is highly recommended that the application rate of co-digestate should not exceed the crop fertilization rate based on N supplement. With these results, it was concluded that co-digestate could be used as an alternative fertilizer for chemical fertilizer. More study is needed for the long-term effects of co-digestate application on the soil and water environment.

An Analysis of Inscription Trends of UNESCO World Heritage Cultural Landscapes (유네스코 세계유산 문화경관 등재 경향 분석)

  • Lee, Jaei;Sung, Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.4
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    • pp.18-31
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    • 2024
  • This study examines the inscription trends and characteristics of 121 cultural landscapes inscribed on the UNESCO World Heritage List to gain a comprehensive understanding of their inherent values and attributes. By employing a dual methodology involving descriptive statistical analysis and in-depth case studies, this research investigates the geographical distribution, temporal inscription patterns, selection criteria, and typologies of these landscapes. The data for this study were collected from official documents and databases available on the UNESCO World Heritage Center website, ensuring the reliability and authenticity of the information. The analysis reveals that cultural landscapes are predominantly concentrated in Europe and Asia, with a steady increase in inscriptions since 1992. These landscapes are primarily recognized for their uniqueness in reflecting human-nature interactions, as well as the importance of traditional culture and land-use practices, resulting in their inscription mainly under criteria (iv), (iii), (v), and (ii). Furthermore, cultural landscapes can be broadly categorized into three types: designed landscapes, organically evolved landscapes, and associative landscapes. Among these, organically evolved landscapes, formed through long-term interactions between human activities such as agriculture and industry and the natural environment, constitute a significant proportion. These findings suggest that UNESCO World Heritage cultural landscapes possess a complex value system encompassing nature and culture, tangible and intangible elements, and material and non-material aspects. This necessitates a fundamental shift in the perception and preservation approaches to cultural heritage, requiring an integrated approach that emphasizes the overall context rather than individual elements and focuses on the dynamic process of landscape evolution itself. Moreover, cultural landscapes have the potential to contribute to sustainable development models by fostering regional identity, strengthening community resilience, and promoting sustainable economic growth. Therefore, the preservation and management of cultural landscapes require a perspective that holistically views the dynamic evolution process of the landscape and a governance system based on the active participation of local communities and stakeholders. This study contributes to enhancing the in-depth understanding of the characteristics and values of cultural landscapes and provides a foundation for the selection and management of future cultural landscape heritage sites.