• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.27 no.3
• /
• pp.169-174
• /
• 2021

Today, plastic waste has become a critical social issue due to the increasing of plastic consumption. Korean annual per capita plastic consumption was 132 kg, the most plastic consuming country in the world. Internationally, Carbon Neutral Agreement is underway due to global warming, consumers' interest and needs for biomass-based plastics has also been increased. In this study, film was produced by adding composite use additives to the biomass-based plastics according to concentration, and the resulting changes in discharge volume, melt index, and tensile strength were investigated. Melt index (MI) was significantly higher in PLA and PBAT than in petroleum-based resin LLDPE and LDPE. Also, among the same resin or in the same treatment group, MI has been increased when the heating temperature is increased. The discharge volume and gravity of the BDP-2 to which 4% compatibilizer was added were found to be higher among all treatments, while the tensile strength of MD and TD was also higher. BDP-2 was suitable to the film producing methods for biodegradable film production.

• Journal of Korea Society of Industrial Information Systems
• /
• v.27 no.5
• /
• pp.145-156
• /
• 2022

In recent years, as there is growing concern with ESG (Environmental, Social, and Governance), the strategic direction of business management is changing from maximizing shareholders wealth to maximizing stakeholders value. ESG is reshaping a corporation's supply chain management strategies. The purpose of this study is to explore the ESG challenges in supply chain management. As a result of network text analysis and topic modeling analysis on 3226 news articles, 'Suppliers', 'Sustainability', 'Shared Growth' 'Carbon Neutral', 'Safety and Health', 'Responsible Business Alliance', 'Supply Chain Due Diligence Law' were identified as the main issue. Since ESG initiatives in the supply chain are not limited to the efforts of individual firms, future research should focus on figuring out what difficulties and challenges exist in the diffusion of ESG practices along multi-tiered supply chains, and how to overcome them.

• Microbiology and Biotechnology Letters
• /
• v.51 no.1
• /
• pp.37-42
• /
• 2023

Neutral and non-essential amino acid, glutamine (Gln), plays an essential role in supplying nitrogen to all the amino acids and nucleotides in the mammalian body. Gln is also the most important carbon source that provides intermediates for gluconeogenesis and fatty acid synthesis and supplements the tricarboxylic acid cycle in fast-growing cancer cells. Among the known 14 Gln transporter genes, soluted carrier family 1 member 5 (SLC1A5) has been reported to be closely associated with cancer cell growth. Three variants (v1, v2, and v3) have been derived from SLC1A5. Here, we established a heterologous gene expression system for the active form of human SLC1A5 variant-2 (hSLC1A5v2) in Escherichia coli. v2 is the smallest variant that has not yet been studied. Four expression systems were investigated: pBAD, pCold, pET, and pQE. We also addressed the problem of codon usage bias. Although pCold and pET overexpressed hSLC1A5v2 in E. coli, they were functionally inactive. hSLC1A5v2 using the pBAD system was able to catalyze the successful transport of Gln, even if it was not highly expressed. Initial activity of hSLC1A5v2 for [¹⁴C] Gln uptake in E. coli reached up to 6.73 μmole·min^-1·gDW^-1 when the cell was induced with 80 mM L-arabinose. In this study, we demonstrated a heterologous expression system for the human membrane protein, SLC1A5, in E. coli. Our results can be used for the functional comparison of SLC1A5 variants (v1, v2, and v3) in future studies, to facilitae the developement of SLC1A5 inhibitors as effective anticancer drugs.

• The Journal of Engineering Geology
• /
• v.33 no.3
• /
• pp.403-411
• /
• 2023

The possibility of utilizing radiant solar energy as a renewable energy resource in Tajikistan was investigated by assessing solar irradiance using XGBoost algorithm. Through training, validation, and testing, the seasonality of solar irradiance was clear in both actual and predicted values. Calculation of hourly values of solar irradiance on 1 July 2016, 2017, 2018, and 2019 indicated maximum actual and predicted values of 1,005 and 1,009 W/m², 939 and 997 W/m², 1,022 and 1,012 W/m², 1,055 and 1,019 W/m², respectively, with actual and predicted values being within 0.4~5.8%. XGBoost is thus a useful tool in predicting solar irradiance in Tajikistan and evaluating the possibility of utilizing radiant solar energy.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.5
• /
• pp.675-687
• /
• 2023

The border area between the South and North Korea is considered a stage for promoting Green Détent through the transformation of the Demilitarized Zone into the Green Peace Zone. This paper proposes 'Prosuming-index' composed of items to evaluate the multi-layered nature of industrial and infrastructure projects in the ecological and environmental fields planned in the border area. Based on the prosuming-index, we derived the following four types of potential for Green Detent practice in the border area-first, the Incheon and Ganghwa regions as 'a logistics/human network and agricultural/fishery production area', second, the northern Gyeonggi region as a 'cooperative network area based on the smart technology industries', third, the western Gangwon and the parts of nothern Gyeonggi region, as 'a multiple prosumer's area based on carbon neutral technologies', lastly, the eastern Gangwon region, as 'a transition area from idle or aged infrastructure to green infrastructure through the renewable energy industries'.

• Journal of the Korean Institute of Gas
• /
• v.27 no.4
• /
• pp.116-122
• /
• 2023

In addition to analyzing the hydrogen economy trends of the international community (Korea, the United States, Europe, Japan, etc.), which is being promoted to realize a carbon-neutral society, this study compared and analyzed the differences between the gaseous hydrogen refueling station, which is a key hydrogen-using facility close to the people, and a liquefied hydrogen refueling station that is scheduled to be built in the future. In addition, SAFETI, a quantitative risk assessment program, was used to analyze the safety of liquefied hydrogen refueling stations and In consideration of the individual and societal risks and the ranking of risks by facility, which are conditional allowable areas, a plan to improve safety such as facility layout was proposed

• Membrane Journal
• /
• v.28 no.4
• /
• pp.252-259
• /
• 2018

An acidic, real metal-plating wastewater was treated by a fluidized bed membrane reactor introduced with granular activated carbon (GAC) as fluidized media. With GAC fluidization, there was no increase in suction pressure with time at each flux set-point applied. At neutral solution pH, much less fouling rate was observed than acidic pH under GAC fluidization. Higher solution pH resulted in the increase in particle size in metal-finishing wastewater, thus producing a less dense cake structure on membrane. More than 95% of chemical oxygen demand was observed from the fluidized bed membrane reactor under GAC fluidization. Total suspended solid concentration in membrane permeate was near zero. At the raw wastewater pH, no removal of copper and chromium by the fluidized bed membrane reactor was observed. As the pH was increased to 7.0, removal efficiency of copper and chromium was increased considerably to 99 and 94%, respectively. Regardless of solution pH tested, more than 95% of cyanide was removed possibly due to the strong adsorption of organic-cyanide complex on GAC in fluidized bed membrane reactor.

• Journal of Ginseng Research
• /
• v.41 no.4
• /
• pp.487-495
• /
• 2017

Background: Although flowers of Panax ginseng Meyer (FPG), Panax quinquefolius L. (FPQ), and Panax notoginseng Burk. (FPN) have been historically used as both medicine and food, each is used differently in practice. Methods: To investigate the connection between components and enhancing immunity activity of FPG, FPQ, and FPN, a method based on a rapid LC coupled with quadrupole time-of-flight MS and immunomodulatory activity study evaluated by a carbon clearance test were combined. Results: According to quantitative results, the ratio of the total content of protopanaxatiol-type ginsenosides to protopanaxadiol-type ginsenosides in FPN was 0, but ranged from 1.10 to 1.32 and from 0.23 to 0.35 in FPG and FPQ, respectively. The ratio of the total content of neutral ginsenosides to the corresponding malonyl-ginsenosides in FPN ($5.52{\pm}1.33%$) was higher than FPG ($3.2{\pm}0.64%$) and FPQ ($2.39{\pm}0.57%$). The colorimetric analysis showed the content of total ginsenosides in FPQ, FPG, and FPN to be $13.75{\pm}0.60%$, $17.45{\pm}0.42%$, and $12.45{\pm}1.77%$, respectively. The carbon clearance assay indicated that the phagocytic activity of FPG and FPQ was higher than that of FPN. A clear discrimination among FPG, FPQ, and FPN was observed in the principal component analysis score plots. Seven compounds were confirmed to contribute strongly by loading plots, which may be the cause of differences in efficacy. Conclusion: This study provides basic information about the chemical and bioactive comparison of FPG, FPQ, and FPN, indicating that protopanaxtriol-type ginsenosides and malonyl-ginsenosides may play a key role in their enhancing immunity properties.

• Journal of Mushroom
• /
• v.20 no.4
• /
• pp.263-269
• /
• 2022

This study investigated the culture characteristics of Cryptoporus volvatus, whichis grow naturally in Korea, to determine the suitable environmental conditions for its cultivation. The physiological characteristics of the mycelia were assessed according to the cultivation conditions, to determine the optimal conditions for artificial cultivation. The visual characteristics of the hyphae of Cryptoporus volvatus KACC52303 included an irregular and uneven surface and a fuzzy or cotton-like texture. Under the microscope, its microstructure showed pre-chlamydospore formation, but no clamps were seen. The appropriate culture temperature was found to be a medium/high temperature of approximately 25-30℃, and the optimal pH was found to have a wide range from weakly acidic (pH 4) to neutral (pH 7). In the optimal nutrient source experiment, hyphal growth was shown to be fair in a mixed medium with 2.5% dextrin as the carbon source and 0.1% yeast extract as the organic nitrogen source. Among the various amino acids, organic acids, and inorganic salts tested, the fastest hyphal growth was observed in the presence of leucine, acetic acid or gluconic acid, and KCl or KH₂PO₄, respectively. The column test showed that the best mycelial growth occurred in a mixed medium of 80% pine sawdust, 10% rice bran, and 10% corncob sawdust.

• Clean Technology
• /
• v.29 no.2
• /
• pp.151-159
• /
• 2023

The realization of carbon neutrality requires cooperation from various stakeholders and the utilization of a governance system. The criteria for participating members are crucial for the successful operation of governance, and it is especially necessary for experts who can provide scientific advice for policy implementation to share a framework for successful consensus. In this study, governance model theory and model structure, governance common success factors by case, and the application of governance cases in the climate and environmental sector of Seoul, were investigated and analyzed to derive common success factors in order to present the activity standards of the science and technology experts participating in governance. The study of the model theory suggested that the model structure is commonly composed of a basic condition-process-result structure, and it was confirmed that common success factors can be derived at the process stage which is the activity period of members. Through the case study of common success factors, overlapping factors were found to be reliability, accountability, transparency, networks, and related factors. The validity of the common success factors was verified using the analysis results of satisfaction survey data from Seoul Governance Committee participants. The results confirmed that reliability was the most valuable factor followed by networks, transparency, and responsibility, and it was found that the related factors were appropriately derived. The findings of this study are expected to be used as an activity factor for science and technology experts to increase the acceptability and effectiveness of carbon-neutral policies in the future.