• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.1
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• pp.72-84
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• 2023

The Rural Revitalization Strategy (2018-2022), published by the Chinese State Council in 2018, represents a new period of rural development in China. Suburban areas are more convenient than other rural areas in integrated urban-rural development but are under greater pressure from construction and industrial pollution. As a rural area with a high proportion of rural areas, it would be valuable for Henan province to gain a comprehensive grasp of rural human settlementst while identifying problems and proposing solutions. The purpose of this study is to analyze the satisfaction of the evaluation items based on the usage status and life perception of the residents of Tai Nan village, a suburb-type rural village in Henan province. The study proposes improvement programs based on the evaluation results. As a result of the study, 24 evaluation items were derived and divided into five categories: "Living Service Facilities", "Housing Environment, "Road Environment", "Health & Ecology Environment", and "Social & Cultural Environment". The Fuzzy Comprehensive Evaluation Method was used to find the overall satisfaction level of the human living environment in Tai Nan village, which was "average", among which "Living Service Facilities" was the most important "Health & Ecology Environment" was the least satisfied. Based on these results, an improvement plan is proposed in three stages. First, the living service will be improved while strengthening the facility management of the hygiene and the ecological environment. Second, reasonable improvement of housing and the road environment will be applied. Third, programs will be introduced to cultivate residents' ability to build their own and improve the social and cultural environment. This study provides basic data for the future improvement of rural settlements in the suburban areas of Henan province and is of great significance in gradually improving the the residents' quality of life.

• Korean Journal of Environmental Agriculture
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• v.42 no.1
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• pp.35-43
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• 2023

The fine particulate structure of biochar limits its use as a heavy metal adsorbent, and makes separation of the biochar from the solution technically challenging, thereby reducing recovery of the heavy metals. To address this issue, this study prepared biochar beads under various mixing conditions and investigated their efficiency in removing Pb from aqueous solutions using adsorption models. The biochar beads were produced by mixing alginate and biochar at different ratios: alginate bead (AB), 1% biochar + bead (1-BB), 2.5% biochar + bead (2.5-BB), and 5% biochar + bead (5-BB). The results revealed that the Freundlich isothermal adsorption pattern of the biochar beads to Pb was of the L-type. The highest Langmuir isothermal adsorption capacity (28.736 mg/g) was observed in the 2.5-BB treatment. The dominant mechanism among the kinetic adsorption characteristics of biochar beads for Pb was chemical adsorption. Additionally, the optimal pH range for Pb adsorption was found to be between 4 and 5.5. The highest Pb removal efficiency (97.9%) was achieved when 26.6 g/L of biochar beads were used. These findings suggest that biochar beads are an economical and highly efficient adsorbent that enables separation and recovery of fine biochar particles.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1251-1260
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• 2022

Recently, due to the deterioration of watermains and the detachment of scale which is accumulated on the watermain surface, water quality accidents in a water supply network occur frequently. As scale accumulated on watermains is stabilized, it may not cause water quality accidents under the normal operating condition. However, due to water hammer or transient flow caused by the abrupt velocity and/or direction of flow change, it can be detached from the watermain surface resulting in water quality accidents. To prevent these kinds of water quality accidents, it is required to remove scale by watermain cleaning regularly. Many researches about flushing which is the most popular water cleaning method are focused on the desirable velocity criteria and the cleaning condition to accomplish the effect of flushing whereas less amount of research effort is given to develop a method to consider whether the desirable velocity for flushing can be obtained before flushing is performed. During flushing, the major and minor headloss is occurred when flushing water flows through a hydrant or drain valve. These headloss may slow down the velocity of flushing water so that it can reduce the flushing effect. Thus, in this study, we suggest a method to simulate the flow velocity of flushing water using "MinorLoss Coefficient" and "Emitter Coefficient" in EPANET. The suggested method is applied to a sample network and the water supply network of "A" city in Korea to compare the flushing effect between "flushing through a hydrant" and "flushing through a drain valve". In case of "flushing through a hydrant", if the hydraulic condition ocurring from a watermain pipe connecting to the inlet pipe of a hydrant to the outlet of a hydrant is not considered, the actual flowrate and velocity of a flow is less than the simulated flowrate and velocity of a flow. In case of "flushing through a drain valve", the flushing velocity and flowrate can be easily simulated and the difference between the simulated and the actual velocity and flowrate is not significant. Also, "flushing through a drain valve" is very effective to flushing a long-length pipe section because of its efficiency to obtain the flushing velocity. However, the number and location of a drain valve is limited compared to a hydrant so that "flushing through a drain valve" has a limited application in the field. For this reason, the engineer should consider various field conditions to come up with a proper flushing plan.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.6
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• pp.110-123
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• 2022

Namsan Park in Seoul was designated as a "grand park" in 1954 and is currently operated as an 'Urban Nature Park Area' and four 'neighborhood parks.' However, despite the park's historical and cultural value as an urban park, it has been discussed mainly from a perspective revolving around notions of a mountain or a city wall. To ensure a comprehensive exploration of Namsan Park's history, this study examined public records at the Seoul Metropolitan Archives (SMA), which houses the city's permanent records for preservation and organization. To this end, documents in the SMA Database (DB) were analyzed, yielding 1,359 records concerning Namsan Park. Based on the contents, general characteristics of the urban park were identified through production periods, record types, and disclosure types. Then, essential keywords concerning organizations, people, geographical areas, subjects, and business functions were examined. Finally, the contents and characteristics of Namsan Park in public records were scrutinized, focusing on specific spaces. This research also uncovered important information, such as park drawings, photos, planting lists, plant parcel lists, and significant discussions and decisions regarding the operation and management of the park. Although the public records do not contain a comprehensive history of Namsan Park, it was possible to check the primary historical changes and deliberation processes pertaining to the park's history. Therefore, continuous research intended to interpret and describe public records is expected to identify many implications. In addition, because the public records showed heterogeneous characteristics that center on specific periods and events, an essential task is to advance collaboration and networking with various related institutions, designers, researchers, and citizens.

• Applied Chemistry for Engineering
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• v.34 no.2
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• pp.111-120
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• 2023

The nucleation mechanism was studied using a calcium ion selective electrode (Ca ISE) to observe the formation of CaCO₃, a representative mineral in the CO2 cycle, and to analyze the effect of the Mg/Ca-ratio and temperature on the formation of pre-nucleation cluster (PNC) and CaCO₃. As a result of the experiment, a small amount of crystal was formed. Energy dispersive X-ray spectroscopy (EDS) was used for surface element analysis, and a field emission scanning-electron microscope (FE-SEM) was used for the morphology analysis of synthesized carbonates. These results showed that various shapes of crystalline CaCO₃ (calcite, aragonite, etc.) were observed for each Mg/Ca ratio and temperature. In addition, the calibration plot obtained from Ca ISE showed information on the formation process of CaCO₃. Our results showed that as magnesium ions interfered with the binding of calcium and carbonate ions and delayed the aggregation between PNCs, the nucleation and formation of CaCO₃ were delayed. On the other hand, the temperature showed an opposite trend as compared to the effect of magnesium under our experimental conditions, indicating that temperature accelerated the formation of CaCO₃. Furthermore, the morphology of CaCO₃ clearly changed according to the Mg/Ca ratio and temperature, and it was confirmed that the two factors are very important for CaCO₃ formation in that they could affect the overall process.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.1
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• pp.15-26
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• 2023

Methane production by anaerobic digestion occurs through interspecies electron transfer (DIET), a synthetic metabolism between acetic and methanate bacteria through hydrolysis and acid production steps. In this study, to improve methane yield, the effect of addition of magnetite (Fe₃O₄), a conductor promoting DIET on methane production in food wastewater was investigated, and the effect on methane yield was assessed by methane potential (B_u) and maximum methane production rate [R_m(t₀)] by the operation of batch type anaerobic reactor adding Fe₃O₄. The B_u and R_m(t₀) of food wastewater without Fe₃O₄ were 0.496 Nm³/kg-VSadded and 38.24 mL/day, respectively. The t0 which reached to R_m appeared at 21.06 days during the operation of the anaerobic reactor. The B_u of food wastewater with Fe₃O₄ was 0.502, 0.498, 0.512, 0.510, 0.518, 0.523, 0.524, 0.540, and 0.549 Nm³/kg-VSadded in the treatment of 5, 10, 15, 20, 25, 30, 40, 70, and 100mM-Fe₃O₄, respectively, and the B_u significantly increased to 36.95% with the addition of magnetite in the addition of 15mM-Fe₃O₄. And, the addition of Fe₃O₄ shortened the duration to reach R_m from 21.06 days to the maximum of 14.67 days by the addition of Fe₃O₄. Therefore, the methane yield and production rate of food wastewater significantly improved with the addition of Fe₃O₄.

• Journal of Life Science
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• v.33 no.2
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• pp.158-168
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• 2023

Natural products have been used to mitigate the effects of cancer and infectious diseases, as they feature diverse bioactivities, such as antioxidant, antibacterial, anti-inflammatory, and immunomodulatory effects. Here, we chose 10 natural products that are well-known as pulmonary enhancers and investigated their bactericidal effects on Streptococcus pneumoniae. In the disk diffusion assay, the growth of S. pneumoniae was significantly regulated by G. fructus treatment regardless of extraction method used. We first adopted spraying as a novel delivery method for G. fructus. Interestingly, mice exposed to G. fructus three times a day for 2 weeks were resistant to S. pneumoniae intranasal infection (shown both through body weight loss and survival rates compared to the control group). Moreover, we confirmed that exposure to G. fructus regulated the colonization of the bacteria despite the sustained inflammation in the lung after exposure to S. pneumoniae, indicating that migrated inflammatory immune cells may involve a host defense mechanism against pulmonary infectious diseases. While a similar number of granulocytes (CD11b⁺Ly6C⁺Ly6G⁺), neutrophils (CD11b⁺Ly6C^intLy6G⁺), and monocytes (CD11b⁺Ly6C^intLy6G^-) were found between groups, a significantly increased number of alveolar macrophages (CD11b⁺CD11c^hiF4/80⁺) was detected in BAL fluids of mice pre-exposed to G. fructus at 5 days after S. pneumonia infection. Taken together, our data suggest that this usage of G. fructus can induce protective immunity against bacterial infection, indicating that facial spray may be helpful in enhancing the defense mechanism against pulmonary inflammation and in evaluating the efficacy of natural products as immune enhancers against respiratory diseases.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.1
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• pp.67-74
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• 2023

In this study, for a natural cosmetics market, we sought to explore alternatives that can replace polyvinyl alcohol (PVA) of peel-off packs. A peel-off type pack was prepared by combining pullulan, a water-soluble polysaccharide, and other polysaccharides (sodium hyaluronate, cellulose gum, hydroxyethyl cellulose, sodium alginate, corn starch), and the pH, viscosity, and stability against temperature of each peel-off type pack were confirmed. The thickness and tensile strength of the manufactured film were measured for comparison with the PVA peel-off type pack, and applicability, drying speed, and removal degree were measured. Among them, the pullulan-sodium hyaluronate peel-off type pack showed excellent film formation ability to replace the peel-off type pack containing PVA with 5.12% thin film thickness and 4.23% high film tensile strength. When applied to actual skin, the degree of spread of the pack, the usability that can be uniformly applied, and the formation and removal strength of the film when removed after drying were also similar to the peel-off type pack containing PVA. Therefore, it was confirmed that the film formed of pullulan-sodium hyaluronate showed enough physical properties to replace the PVA of the peel-off type pack as a natural peel-off type pack.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.582-591
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• 2022

This study was conducted to eliminate Myocastor coypusMolina, 1782 (Nutria) from Jeju Special Self-Governing Province, South Korea. Habitat identification and eradication were carried out from September to November 2013, and a survey was carried out until June 2022 to check whether the eradication was successful. The habitat was identified with unmanned cameras, interviews, and literature surveys, and the capture was performed using the trapping method with food to attract nutria to the habitat area. The study area for the follow-up survey, which was set relatively wide considering nutria's home range, included wetlands and rivers within 4.0 km² of the habitat area (eradication area). As a result, nutria's habitat was confirmed only at Songdang Ranch, Songdang-ri, of Jeju Island, with traces of habitat (footprints, excrement, and burrows) confirmed in waterways and ponds within the pasture. Eight individuals were captured, including four females, three males, and one individual in too advanced a state of decay to identify the sex. The follow-up survey thoroughly investigated the habitat and its surroundings, focusing on three areas with permanent water, Seongeup Reservoir, Cheonmi Creek, and Molsuni Pond, but no signs of habitat were identified. Therefore, it is determined that nutria inhabiting Jeju Island has been completely eradicated. It is believed that the successful eradication of nutria in the Jeju Special Autonomous Region was possible due to a synergy between 1) the eradication of nutria at the beginning of the settlement phase through rapid capture after confirming the nutria habitat and 2) the delayed expansion period because of rare presence of wetlands, where water is constantly stagnant, on Jeju Island. These results imply that quickly identifying the ecological characteristics of the species and preventing disturbances before they or at the beginning of the ecological disturbance through control and eradication at the initial stage of settlement before the expansion stage is an effective measure to cope with the influx of alien species.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.148-156
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• 2022

Ecological occupation in irrigation ponds is a well-acknowledged fact that is essential for biodiversity conservation in agricultural ecosystems. However, there are few studies on the ecological functions and relationship between a paddy field and irrigation using macroinvertebrates in an environmentally friendly paddy field. The objective of this study is to identify the community and distribution characteristics of macroinvertebrates in an agricultural paddy field and irrigation pond ecosystems, and to provide basic data on the ecological function of an environmentally friendly paddy field. Macroinvertebrate sampling was conducted from May to September in an agricultural paddy field and irrigation pond in an environment-friendly paddy field in Boryeong city. We conducted a study to identify the distribution characteristics using macroinvertebrate species analysis, such as Functional Feeding Groups (FFGs), Habitat Oriented Groups (HOGs), rarefaction curve, and a two-way dendrogram. A total of 37 species of macroinvertebrates in 28 families, 13 orders were collected study during the period of the investigation. Dominant taxa of macroinvertebrates included Coleoptera, Hemiptera, and Odonata. In terms of FFGs, predators and gathering collectors accounted for approximately 70%, in relation to HOGs, and climbers and swimmers occupied more than 50% from both the paddy field and irrigation pond. With respect to the rarefaction curve, the irrigation pond (July) was high as E (S, 141)=18 species, while the paddy field (May) was comparatively low as E (S, 141)=9 species. In conclusion, our results revealed that macroinvertebrates, such as Notonecta triguttata, Peltodytes intermedius, Appasus major, Laccotrephes japonensis, Appasus japonicus, Sigara substriata, Enochrus simulans, and Sternolophus rufipes, were used as a habitat and spawning ground in both paddy field and irrigation pond. The irrigation pond appears to be a very important spawning ground for macroinvertebrates.