• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.55-66
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• 2007

This study was conducted to analyze the distribution patterns of wintering waterbird communities in relation to local environmental factors in the urban streams of Seoul, Korea. A field survey was conducted at 66 sites of 5 tributaries and the main channel of the Hangang River in Seoul in January 2006. The total of 65 species and 39,560 individuals were recorded in the field survey. There were 48 species and 28,989 individuals in the Hangang River, 14 species and 1,395 individuals in the Tancheon stream, 15 species and 2,306 individuals in the Jungrangcheon stream, 22 species and 5,990 individuals in the Anyangcheon, 18 species and 283 individuals in the Changrungcheon stream, and 24 species and 597 individuals in Gokrungcheon stream. The dominant species were Anas platyrhynchos (22.65%), A. poecilorhyncha (14.01%), Aythya ferina (13.26%), Aythya fuligula (8.04%), and Mergus merganser (7.03%). Among the 16 species (with 30,650 individuals) of ducks, the dabbling and diving ducks were 8 species with 18,286 individuals and 8 species with 12,364 individuals, respectively. Through the principal component analysis, the study sites were classified into four main groups according to the similarity of their waterbirds' species compositions: 3 tributaries in the urban area (Group 1), 2 tributaries in the rural area (Group 2), one in the rural area, one in the urban area, the urban area in Hangang River (Group 3) and the main channel of the Hangang River in the urban area (Group 4). Species diversity index and species evenness were the highest in Group 1, while the lowest Group 2. Analysis on their environmental factors showed that the waterbirds wintering in urban streams of Seoul prefer broad water width, low water depth and broad resting sites.

• Journal of dental hygiene science
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• v.6 no.2
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• pp.133-138
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• 2006

To find out influence of water fluoridation program on the economic benefit effect, this study analyzed comparatively dental treatment indicators obtained from dental clinics at Sangdang-gu in Chenongju City, fluoridated community and Manan-gu in Anyang City, non-fluoridated community, from January 1, 2003 to the end of June, and the results are as follows: 1. If water fluoridation program is carried out in Anyang, non-fluoridated community, the number of treatment from caries and disease of tissues around dental pulp and root apex from age 6 to 18 for the first half of year 2003 is expected to decrease by 1,272, 636 for low estimation, and 1,908 for high estimation. And the treatment cost is expected to decrease by 40,888,000 Wons, 20,444,000 Wons for low estimation, and 61,333,000 Wons for high estimation. 2. Assuming that water fluoridation program is spread to all over the country, the number of treatment per year is expected to decrease by 2,492,018, 1,246,009 for low estimation, and 3,738,027 for high estimation. And the treatment cost is expected to decrease by 80,105,075,000 Wons, 40,052,537,000 Wons for low estimation and 120, 157,612,000 Wons for high estimation respectively. 3. For Yeong-un water supply management office which has 48,925 water supply personnel, the benefit/cost rate was 2.9 times, and for Jibuk water supply management office which has 239,751 water supply personnel, the benefit/cost rate was 9.0 times. As the water supply personnel increased, the cost increase of water fluoridation program was little and as the scale got large, the economic effect was very large. Improving national oral health is thought to be associated with expense retrenchment of oral health insurance financial. So it may need to extend using tap water to all the area of the country and additionally establish confidence through an active public relations and education of water fluoridation program.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.106-127
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• 2019

This study aims to understand spatio-temporal variations of macrozoobenthos community in Han River (HRE), Geum River (GRE), and Nakdong River estuaries (NRE) of Korea, sampled by National Survey of Marine Ecosystem. The survey was seasonally performed at a total of 20 stations for three years (2015-2017). Sediment samples were taken three times with van Veen grab of $0.1m^2$) areal size and sieved through a 1 mm pore size mesh on site. A total of 1,008 species were identified with 602 species in HRE, 612 in GRE, and 619 in NRE, showing similar number of species between estuaries. Mean density was $1,357ind./m^2$, showing the high in NRE ($1,357ind./m^2$), mid in GRE ($1,357ind./m^2$), and low in HRE ($1,127ind./m^2$). Mean biomass was $116.8g/m^2$, showing similar variations to density ($174.2g/m^2$ in NRE, $129.0g/m^2$ in GRE, $49.0g/m^2$ in HRE). Polychaeta dominated in number of species and density in three estuaries. Biomass-dominated taxon was Mollusca in HRE and GRE, and Echinodermata in NRE. Polychaetous species dominated all three estuaries over 4% of density, such as Dispio oculata, Heteromastus filiformis and Aonides oxycephala in HRE, Heteromastus filiformis and Scoletoma longifolia in GRE, and Pseudopolydora sp. and Aphelochaeta sp. in NRE, showing various density between estuaries. Community structure was determined by various environmental variables among estuaries such as mean grain size and sorting (HRE), salinity and mean grain size (GRE), and salinity, dissolved oxygen, loss on ignition and mud content (NRE). Our study demonstrates the application of different measures to manage ecosystems in three estuaries. HRE needs to alleviate sedimentary stressors such as sand mining, land-filling, dike construction. Management of GRE should be focused on fresh water control and sedimentary stressors. In NRE, monitoring of dominant benthos and process study on hypoxia occurrence in inner Masan Bay are necessary.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.2
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• pp.87-102
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• 2022

To clarify the spatial distribution pattern of macrozoobenthos in Korean coastal waters in the summer season and investigate the relationship between community structure and benthic environmental factors, field surveys on community structure and benthic environmental factors were conducted at 117 stations in August 2017. A total of 613 macrobenthic species were identified, with the mean density of 1,228 ind./m² and the mean biomass (wet weight) of 110.9 g WW/m². Rich biodiversity was found at stations near Wando and along the coast of the East Sea, and there is a trend that stations with greater biodiversity also showed higher mean density as well. The dominant species in all the coastal areas in Korea was Heteromastus filiformis, which were found at most of the stations during the survey. The relatively deep areas in the East Sea were dominated by Magelona johnsoni and Maldane cristata, which were the third and ninth dominant species in the study areas, respectively. Pseudopolydora kempi and Rhynchospio sp. were observed only at the station located in the Nakdong River estuary. From the cluster analysis the stations could be clustered into three station groups with more similar faunal composition. Group A was located in the eastern coast, characterized with deep water depth and low levels of sand contents, while Group B was located in the southern coast, characterized by shallow depth of water and high content of mud and organic matter. Lastly, Group C was in the western coast, demonstrating low levels of mud content and organic matters. The biodiversity of macrobenthic species in the study area showed high positive correlation coefficients with benthic environmental factors such as sorting, clay, silt, and contents of organic matter in sediments, but negatively correlated with the sand contents. Major dominant species, Theora lata and Eriopisella sechellensis, both showed negative correlation coefficients with the sand contents, but a relatively high positive correlation with the levels of organic contents.It can be concluded that the spatial distribution patterns of macrobenthic organisms in Korean coastal waters are affected by depth, sediment type, and contents of organic matters.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.4
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• pp.29-39
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• 2023

In this study, an analysis of medical waste generation characteristics was conducted, differentiating between ordinary situation and the outbreaks of massive infectious diseases. During ordinary situation, prediction models for medical waste quantities by type, general medical waste(G-MW), hazardous medical waste(H-MW), infectious medical waste(I-MW), were established through regression analysis, with all significance values (p) being <0.0001, indicating statistical significance. The determination coefficient(R2) values for prediction models of each category were analyzed as follows : I-MW(R2=0.9943) > G-MW(R2=0.9817) > H-MW(R2=0.9310). Additionally, factors such as GDP(G-MW), the number of medical institutions (H-MW), and the elderly population ratio(I-MW), utilized as influencing factors and consistent with previous literature, showed high correlations. The total MW generation, evaluated by combining each model, had an MAE of 2,615 and RMSE of 3,353. This indicated accuracy levels similar to the medical waste models of H-MW(2,491, 2,890) and I-MW(2,291, 3,267). Due to limitations in accurately estimating the quantity of medical waste during the rapid and outbreaks of massive infectious diseases, the generation unit of I-MW was derived to analyze its characteristics. During the early unstable stage of infectious disease outbreaks, the generation unit was 8.74 kg/capita·day, 2.69 kg/capita·day during the stable stage, and an average of 0.08 kg/capita·day during the reduction stage. Correlation analysis between generation unit of I-MW and lethality rates showed +0.99 in the unstable stage, +0.52 in the stable stage, and +0.96 in the reduction period, demonstrating a very high positive correlation of +0.95 or higher throughout the entire outbreaks of massive infectious diseases. The results derived from this study are expected to play a useful role in establishing an effective medical waste management system in the field of health care.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.21-30
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• 2005

Feeding behavior of foraging ants including visiting numbers, species, and preference on insect cadavers killed by entomopathogenic nematodes <(Heterorhabditis sp. KCTC 0991BP (He) and Steinernema carpocapsae KCTC 0981BP (Sc)> and their symbiotic bacteria was investigated in Dongrae Benest Golf Club, Anyang Benest Golf Club, Gapyung Benest Golf Club and Ulsan Golf Club. The number of ants, kinds and numbers of cadavers taken away by ants were different depending on killing method, golf club and site within the golf courses (fairway and rough). The feeding preference of ants was the lowest on cadavers killed by He. At Dongrae Benest Golf Club Lasius japonicu ($75{\pm}5\%$) and Monomorium floricola ($10\%$) took away cadavers only at the rough. The visiting rate of ants was $85{\pm}6\%$ at the rough, but none at the fairway by 16 hours. The taken rate of cadavers by ants was the lowest on He-killed cadavers representing $16.7\%$ compared with $40.0\%$ on Sc-killed cadavers, $53.3\%$ on fenitrithion-killed cadavers, and $56.7\%$ on natural dead cadavers by 12 hours. At the rough of hole 6 in Anyang Benest Golf Club, Tetramorium tsushimae ($33{\pm}12\%$), Pheidole fervida ($17{\pm}15\%$), Camponatus japonicus ($10\%$), Formica japonica ($7{\pm}6\%$), Paratrechina flavipes ($3{\pm}6\%$), and Crematogaster matsumurai ($3{\pm}6\%$) took away cadavers, but $23{\pm}15\%$ of cadavers were not visited by ants. Ants took away $40\%$ of Sc-killed cadavers, $16.7\%$ of frozen-killed cadavers, and $3.4\%$ of He-killed cadavers. The number of visiting ants was low at the hole 9 of Cherry course in Gapyung Benest Golf Club and only Tetramorium tsuhimae and Paratrechina flavipes were found from one site. The density of entomopathogenic nematodes did not influence ant visiting on cadavers, but burying affected ant visiting. Although ants took away unburied cadavers, buried cadavers were taken away at the hole 6 of Dongrae Benest Golf Club by 16 hours. Ant visiting had the same tendency on symbiotic bacterium-treated biscuit as nematode-killed cadavers. The visiting was less on biscuit inoculated by Photorhabdus sp., a symbiotic bacterium of He than on biscuit inoculated by Xenorhabdus nematophila, a symbiotic bacterium of Sc.

• The Journal of the Petrological Society of Korea
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• v.19 no.2
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• pp.109-121
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• 2010

Mt. Mudeung is located in Gwangju city, Damyang-Gun, Hwasun-Gun and its round form give us the mood of soft and rich. Its location is $126^{\circ}06'-127^{\circ}01'E$ and $35^{\circ}06'-35^{\circ}10'N$ and its highest peak is Cheonwang-bong with the height of 1,187 m. The Gwangju city is located in the West of Mt. Mudeng and the mountain range with a small basin in its East. The pavilion such as the Soswaewon, Songganjeong, Sigyongjeong are distributed along the stream in the north of Mt. Mudeung. The mountain is formed from the volcanic activity, Gwangju cauldron during the Cretaceous. The top part of Mt. Mudeung is composed of dark gray quartz-andesite and its K-Ar whole rock age is $48.1{\pm}1.7Ma$. The composition of the north area, where the Wonhyosa temple is located, is micrographic granite, whereas the composition of south area is rhyolite mainly. The main ridge of Mt. Mudeung runs from North, starting from the Bukbong, to south, passing Cheonwangbong, Jangbuljae and ending Anyangsan. Geologic feature of the mountain includes volcanic landform, mountaineous landform, and stream landform. The Seosukdae, Ipseokdae, Gyubongam, which are main ridges and formed from volcanic activity, are composed of mainly columnar joint. Saeinbong and Majipbong in the south-west are composed of mainly cliff and dome. The typical erosion landform of the mountain has three different types of the weathering-cave, each of which reflect the property of the original rock. Four different area of wide block stream, they makes the geological feature of spring-water, though its scale is small compared to that of water fall.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.1
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• pp.231-243
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• 1994

A stochastic programming model for river water quality management was developed. River water quality, river flow, quality and flowrate of the wastewater treatment plant inflow were treated as random variables in the model. Withdrawal for water supply and submerged weir reaeration were included in the model itself. A probabilistic model was formulated to compute the expectation and variance of water quality using Streeter-Phelps equation. Chance constraints of the optimization problem were converted to deterministic equivalents by chance constrained method. Objective function was total annual treatment cost of all wastewater treatment plants in the region. Construction cost function and O & M cost function were derived in the form of nonlinear equations that are functions of treatment efficiency and capacity of treatment plant. The optimization problem was solved by nonlinear programming. This model was applied to the lower Han River. The results show that the reliability to meet the DO standards of the year 1996 is about 50% when the treatment level of four wastewater treatment plants in Seoul is secondary treatment, and BOD load from the tributary inflows is the same as present time. And when BOD load from Tanchon, Jungrangchon, and Anyangchon is decreased to 50%, the reliability to meet the DO standards of the year 1996 is above 60%. This results indicated that for the sake of the water quality conservation of the lower Han River, water quality of the tributaries must be improved, and at least secondary level of treatment is required in the wastewater treatment plants.

• Korean journal of applied entomology
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• v.18 no.4 s.41
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• pp.153-160
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• 1979

The present experiments were carried out to reduce the population density of adult pine gall midge, Thecodiplosis japonensi,s UCHIDA et INOUYE, by means of spray the sticky agent C-4, on the ground, herbacious plantation and foliar leaf of pine trees at Sanbonli,. Anyang, Kyungido. And also the 3 periods of treatment, such as before 2 weeks( I ), before 1 week (II) from the peak emergence period and peak emergence period (III) were applied. The experimental results obtained were as follows. (1) The formula of selected sticky agent C-4 was $70\%$ of castor oil, $25\%$ of damar resin and $5\%$ of carnauba wax, and it showed the best both on stickiness and duration, and lower phytotoxicity to the host plant. (2) The reduction of population densities of the adult PGM were $68\%$ and 78f: in the G-I and G-II treatment plot respectively, which compared to control, on the ground spray. (3) And the reduction of population densities were $63\%$ and about $90\%$ in the P-I and P-II plot respectively when the agent was sprayed on the herbacious plantation. (4) The rates of gall formation were $32.8\%,\;40.8\%\;and\;59.4\%$ in the spray plots of F-I, F-II, and F-III respectively, and there was no significant difference among the upper, middle and lower parts of the treated host plant in the rates of gall formation. (5) The effective stage of sticky agent application were considered as before one week from the peak emergence period in tile all types of treatment.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.176-182
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• 2009

Hydrogen producing bacterium, strain MeL 6-2 was isolated from the sludge of the factory areas in Anyang through the acclimation in basal salt medium (BSM) supplemented with 10 g/L of sucrose. Isolated strain MeL 6-2 was a facultative anaerobe which could grow in both aerobic and anaerobic environments. An aerobically grown pure culture isolated from enriched culture was analyzed by 16S rDNA sequencing and identified as Rhodopseudomonas sp. MeL 6-2. Effects of the concentrations of glucose and sucrose on the hydrogen production rate and the hydrogen production yield were investigated. When glucose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow without lag phase. An increased glucose concentration increased the specific hydrogen production rate linearly to $4.2\;mmol-H_2{\cdot}L^{-1}{\cdot}h^{-1}$ at 10 g/L, and $60\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$, but decreased slightly as the concentration increased to 12 g/L. The hydrogen production yield was maintained over a range from 2.6 to $3.1\;mol-H_2{\cdot}mol-glucose^{-1}$. When sucrose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow after ten hours. An increased sucrose concentration increased the specific hydrogen production rate and the hydrogen production yield to $163\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$ and to $4.5\;mol-H_2{\cdot}mol-sucrose^{-1}$, respectively.