• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.357-367
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• 2018

Recent earthquakes in Gyeongju and Pohang have raised interest in liquefaction in South Korea. Liquefaction, which is a phenomenon that excessive pore pressure is generated and the shear strength of soil is decreased by repeated loads such as earthquakes, causes severe problems such as ground subsidence and overturning of structures. Therefore, it is necessary to identify and prepare for the possibility of liquefaction in advance. In general, the possibility of liquefaction is quantitatively assessed using the Liquefaction Potential Index (LPI), but it takes a lot of time and effort for performing site response analysis which is essential for the liquefaction evaluation. In this study, a simple method to evaluate the liquefaction potential without executing the site response analysis in a downtown area with a lot of borehole data was proposed. In this simple method, the correlation between the average shear wave velocity of the target location ground and the LPI divided by thickness of liquefiable layer was established. And the applicable correlation equation for various rock outcrop accelerations were derived. Using the 104 boreholes information in Seoul, the correlation equation between LPI and the shear wave velocity (ground water level: 0m, 1m, 2m, 3m) is obtained and the possibility of liquefaction occurrence in Seoul and Gyeongju is evaluated. The applicability of the proposed simple method was verified by comparing the LPI values calculated from the correlation equation and the LPI values derived using the existing site response analysis. Finally, the distribution map of LPI calculated from the correlation was drawn using Kriging, a geostatistical technique.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.401-408
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• 1985

In order to develop new types of product which can offer a sanitary and preservative duality, and convenience to consumers in marketing and cooking particularly in urban area, two processing methods of ready-to-cook food materials with dark fleshed fishes like sardine and mackerel were investigated. A method applied, in this work, is processing of ready-to-cook sardine meat "surimi" in which sardine meat is treated with alkaline solution to stabilize myofibrillar proteins, washed thoroughly with water to remove soluble components, and added with a proper amount of polyphosphate and sorbitol to enforce the functional property of meat such as water holding capasity, elasticity, and gel strength. The textural properties of fish meat paste made from the "surimi" meat were greatly dependent upon the stability of myofibrillar proteins and the elimination of water soluble components. The salt soluble proteins of sardine meat were so unstable in post-mortem stage that the gel forming ability was lost within 3 days at $5^{\circ}C$ storage and 2 to 3 weeks even at $-20^{\circ}C$ although the freshness was well kept for a week at $5^{\circ}C$ and several months of storage at $-20^{\circ}C$. A proper way of treatment to keep the proteins stable was that fish meat must be washed with $0.4\%$ sodium bicarbonate solution followed by 3 to 4 times washing with water. This resulted in removal of $80\%$ water soluble proteins and 50 to $60\%$ lipids. The addition of polyphosphate and sorbitol affected the stability of proteins during the storage of "surimi" meat. When phosphate and sorbitol were added in the ratio of $0.3\%:\;0.3\%,\;0.6\%:\;3\%,\;0.6\%:\;6\%,\;0:\,0.3\%\;and\;0.3\%:\;0$, the gel forming ability terminated in 35 days, 21 days, 14 days, 14 days, and 14 days of storage at $-30^{\circ}C$, respectively, while that of the control was 7 days. And it was also noteworthy that at least 8.0 mg/g of salt soluble protein nitrogen content was required for gel formation.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.238-272
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• 2002

This study was intended to find out the factors affecting to the IADL, allowing objective assessment of physical function status of increasing elderly populations. The subjects of 635 elderly persons aged over 65 years old who live in Taejon metropolitan city were interviewed during the two-month period from June to July of 2000. The IADL of Older American Resources and Services(OARS), developed in Duke medical college of USA, was interpreted for use. The study results were statistically processed using SPSSWIN(ver 10.0) and conferred the following results: 1. Among the seven items of IADL, the women showed higher rates of 'yes' in items about using the telephone, getting to the places out of walking distance, going shopping for groceries, taking their own medicine while outnumbered by the men only in the item about managing their own money, without significant differences between them in items about preparing their own meals and doing their own housework. 2. In terms of IADL scores, $82.0\%$ of subjects showed the normal range of scores and $18.0\%$ were under the normal range, meaning dysfunction IADL. Specifications of general characteristics revealed that more dysfunctional were the male subjects, the higher age groups who are more than 75 years old, the higher educated groups, the groups who live in nursing homes, the groups without a spouse. 3. Based on daily activities, lower scores of IADL were found in the subjects who don't go out, who don't have recreational activities, who don't attend elderly gatherings in their neighborhood, who don't hold social meetings. Specifications of psychological traits revealed that more dysfunctional were IADL in the subjects who don't feel satisfied with their lives of the past or the present, who have a deep feeling of isolation, and who don't have the will to live. 4. Among 7 items of health habits, only the subjects who don't regular exercise had lower scores of IADL than those who do. According to HPI, the lower HPI, the more dysfunctional. 5. Based on the factors associated with IADL, the odds ratio of the subjects who don't live together with their families were 1.53 times that of the ones who do, who are educated 3.22 times that of the ones who are not, who don't have spouses 2.09 times that of the ones who do, who don't go out 4.35 times that of the ones who frequently go out, who don't recreational activities for an interest 2.64 times that of the ones who do, who don't attend elderly gatherings in their neighborhood 1.47 times that of the ones who do, who don't hold social meetings 2.23 times that of the ones who do, who don't feel satisfied with their present living 1.43 times that of the ones who do, who have a feeling of isolation 1.53times that of the ones who don'1, who have the weak will to live 3.21 times that of the ones who have the strong one, and who don't regular exercise 2.45 times that of the ones who do. 6. Logistic regression analysis of the study results found that such factors are significantly related as the degree of education, with/without spouse, social meetings, the will to live, and regular exercise, and that higher rates of dysfunctional subjects were in the more educated group, in the group without spouse, in the group who don't frequently go out, who don't have social meetings, who have the weak will to live, and who don't exercise.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.385-393
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• 2007

Benthic macroinvertebrate communities were studied after a small dam removal from the mid-section of the Gyeongan stream in Gyeonggi-do, Korea. Quantitative sampling was conducted at immediately upstream (upper) and downstream (lower) sites from the dam as well as at the site where the dam was located (dam site: middle) using a Surber sampler (50$\times$50 cm, mesh 0.25 mm), four times (November 2004, May 2005, January 2006, and May 2006) after the dam removal. As a result, 46 species of benthic macroinvertebtates, belonged in 35 genera, 27 families, 11 orders, 5 classes, and 4 phyla, were sampled from the stream sites, but the number of species that occurred at each sampling trial was different (ranged 3$\sim$17 spp.) according to the seasons and sites. Approximately one year after the dam removal, the species number has in-creased and taxa composition has changed as the microhabitat became more heterogeneously due to a riffle formation in the upstream site. Chironomid larvae and tubificid worms, which are common in Korean urban streams, were the dominant species, while Hydropsyche kozhantschikovi was the 2nd dominant species at some sampling trials. In general, McNaughton's dominance indices decreased and Shannon species diversity indices increased approximately one year after the dam removal. Compositions of collector-filterers, clingers, and swimmers increased as hydropsychid caddisflies, heptageniid mayflies, and baetid mayflies increased, respectively, in the upstream site. The group pollution index and the ecological score using benthic macroinvertebrates both indicated that water environment has been improved in the upstream site after the dam removal.

• Journal of Environmental Impact Assessment
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• v.24 no.5
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• pp.456-471
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• 2015

Emission source term is one of the strong controlling factors for the air quality simulation capability, particularly over the urban area. Ulsan is an industrial area and frequently required to simulate for environmental assessment. In this study, two CAPSS (Clean Air Policy Support System) emission data; CAPSS-2003 and CAPSS-2010 in Ulsan, were employed as an input data for WRF-CMAQ air quality model for emission assessment. The simulated results were compared with observations for the local emission dominant synoptic conditions which had negative vorticities and lower geostrophic wind speed at 850hPa weather maps. The measurements of CO, $NO_2$, $SO_2$ and $PM_{10}$ concentrations were compared with simulations and the 'scaling factors' of emissions for CO, $NO_2$, $SO_2$, and $PM_{10}$ were suggested in in aggregative and quantitative manner. The results showed that CAPSS-2003 showed no critical discrepancies of CO and $NO_2$ observations with simulations, while $SO_2$ was overestimated by a factor of more than 12, while $PM_{10}$ was underestimated by a factor of more than 20 times. However, CAPSS-2010 case showed that $SO_2$ and $PM_{10}$ emission were much more improved than CAPSS-2003. However, $SO_2$ was still overestimated by a factor of more than 2, and $PM_{10}$ underestimated by a factor of 5, while there was no significant improvement for CO and $NO_2$ emission. The estimated factors identified in this study can be used as'scaling factors'for optimizing the emissions of air pollutants, particularly $SO_2$ and $PM_{10}$ for the realistic air quality simulation in Ulsan.

• Ecology and Resilient Infrastructure
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• v.3 no.4
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• pp.221-230
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• 2016

Multi-functional floating wetland island (mFWI) was developed in order to prevent algal bloom and to improve water quality through several unit purification processes. A test bed was applied in the stagnant watershed in an urban area, from the summer to the winter season. For the advanced treatment, an artificial phosphorus adsorption/filtration medium was applied with micro-bubble generation, as well as water plants for nutrient removal. It appeared that the efficiency of chemical oxygen demand (COD) and total phosphorus (T-P) removal was higher in the warmer season (40.9%, 45.7%) than in the winter (15.9%, 20.0%), and the removal performance (suspended solid, chlorophyll a) in each process differs according to seasonal variation; micro-bubble performed better (33.1%, 39.2%) in the summer, and the P adsorption/filtration and water plants performed better (76.5%, 59.5%) in the winter season. From the results, it was understood that the mFWI performance was dependent upon the pollutant loads in different seasons and unit processes, and thus it requires continuous monitoring under various conditions to evaluate the functions. In addition, micro-bubbles helped prevent the formation of anaerobic zones in the lower part of the floating wetland. This resulted in the water circulation to form a new healthy aquatic ecosystem in the surrounding environment, which confirmed the positive influence of mFWI.

• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.629-637
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• 2016

In this present study, we identified the $SO_2$ effect on $O_3$ retrieval from the Ozone Monitoring Instrument (OMI) measurement over Chinese Industrial region from 2005 through 2007. The Planetary boundary layer (PBL) $SO_2$ data measured by OMI sensor is used in this present study. OMI-Total Ozone Mapping Spectrometer (TOMS) total $O_3$ is compared with OMI-Differential Optical Absorption Spectrometer (DOAS) total $O_3$ in various $SO_2$ condition in PBL. The difference between OMI-TOMS and OMI-DOAS total $O_3$ (T-D) shows dependency on $SO_2$ (R (Correlation coefficient) = 0.36). Since aerosol has been reported to cause uncertainty of both OMI-TOMS and OMI-DOAS total $O_3$ retrieval, the aerosol effect on relationship between PBL $SO_2$ and T-D is investigated with changing Aerosol Optical Depth (AOD). There is negligible aerosol effect on the relationship showing similar slope ($1.83{\leq}slope{\leq}2.36$) between PBL $SO_2$ and T-D in various AOD conditions. We also found that the rate of change in T-D per 1.0 DU change in PBL, middle troposphere (TRM), and upper troposphere and stratosphere (STL) are 1.6 DU, 3.9 DU and 4.9 DU, respectively. It shows that the altitude where $SO_2$ exist can affect the value of T-D, which could be due to reduced absolute radiance sensitivity in the boundary layer at 317.5 nm which is used to retrieve OMI-TOMS ozone in boundary layer.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.44-58
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• 1994

This study was conducted to examine the levels of total and organic mercury in the scalp hair of the elementary school children and adults, and their relationship with the consumption pattern of fishes and shellfishes. The scalp hair samples were collected from the occipital part of 115 children and 131 adults in costal, urban and rural areas of Kyungpook province from June to August 1991. The mercury content was analysed by the atomic absorption spectrophotometer (model IL. 555) with atomic vapor accessory (model IL. 440). The total and organic mercury contents of hair were significantly higher (p<0.01) among the children who prefer fish and/or shellfish (7.728 ppm, 6.610 ppm), and canned fish and/or fish pastes (6.969 ppm, 5.885 ppm) than those who prefer meat (4.822 ppm, 3.905 ppm) and vegetables (3.974 ppm, 3.224 ppm). The children who prefer to eat the canned fish without cooking showed a higher mercury content than the children who prefer to eat it as stew or mixed with vegetables (p<0.01). There was a dose-response relationship between the intake frequency of canned fish, raw fish and cooked fish and the content of total and organic mercury of hair, the children who eat fish almost everyday showed 2 times higher than those who eat rarely (p<0.01). The mercury content in the hair of the children who eat raw fish was significantly higher than that of the children who eat boiled or broiled fish (p<0.01). The total and organic mercury contents of adult scalp hair increased with age up to the forties and slightly decreased in the fifties. The mercury contents of those who were engaged in the fishery and raw fish restaurant were 2 times higher than those of the farmers. The mercury content of the persons who were favorite dishes of fish and shellfish were most high, and who prefer raw fish were 2 times higher than those of the persons who prefer vegetables and broiled fish. The contents of total and organic mercury in adult scalp hair showed also a increasing tendency with the intake frequency of raw and cooked fish.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.145-172
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• 1984

In order to assess the physical growth pattern of Korean Youth, the authors measured the body height, body weight, chestgirth and sitting height of 40967 persons (24832 males and 16135 females) from primary schools, middle and high schools and colleges of metropolitan (urban) and rural areas, and calculated the mene, standard deviation, standard error and coefficient variance of the body weight chestgirth, sitting height and various pertinent index by body height to demonstrate the standard physical growth and development by body height of sex and age. The following conclusions were obtained. 1. Physical growth and development: Rapid growth of physical growth in terms of body height has been observed among males in the age $7{\sim}15$ and among female $7{\sim}13$. Growth in terms of body height turned out to be slower among students of higher age by both sexes. The age of cross over between to sexes is between 10 to 13 years where upon girls out grows boys. Maximum annual growth were upon girls out grows boys. Maximum annual growth were both of 6.16cm from 8 to 9 years old and 12 to 13 years old for boys and 7.2cm from 8 to 9 and 6.1cm from 9 to 10 for girls. This indicates that girls enter a rapidly growing stage 2 years earlier than boys. Meanwhile, prominent improvement in body height of national students over period of ten year was noticed. 2. The distribution status of body height by age: The distribution status of body height by age were as follows; 7 year of age: boys-30cm range of body height from 104.0cm to 133.9cm, girls-27cm from 104.0cm to 130.9cm 8 year of age: boys-30cm from 116.0 to 145.9cm girls-33cm from 113.0 to 145.9cm 9 year of age: boys-30cm from 116.0 to 145.9cm girls-33cm from 113.0 to 145.9cm 10 year of age: boys-39cm from 116.0 to 154.9cm girls-39cm from 119.0 to 157.9cm 11 year of age: boys-45cm from 119.0 to 163.9cm girls-39cm from 122.0 to 160.9cm 12 year of age: boys-45cm from 125.0 to 169.9cm girls-42cm from 125.0 to 166.9cm 13 year of age: boys-45cm from 128.0 to 172.9cm girls-42cm from 128.0 to 169.9cm 14 year of age: boys-48cm from 131.0 to 178.9cm girls-36cm from 134.0 to 169.9cm 15 year of age: boys-42cm from 137.0 to 181.9cm girls-33cm from 137.0 to 169.9cm 16 year of age: boys-39cm from 146.0 to 184.9cm girls-30cm from 143.0 to 172.9cm 17 year of age: boys-39cm from 146.0 to 184.9cm girls-27cm from 143.0 to 169.9cm 18 year of age: boys-36cm from 152.0 to 187.9cm girls-27cm from 146.0 to 172.9cm 19 year of age: boys-30cm from 155.0 to 184.9cm girls-24cm from 146.0 to 169.9cm 20 year of age: boys-24cm from 158.0 to 181.9cm girls-l8cm from 149.0 to 166.9cm 3. Standard values of body weight, chest-girth and sitting height by body height of age were found all age groups from 7 to 20 years old and listed in tables from3-a to 16-a. 4. Standard values of relative body weight, relative chestgirth and relative sitting height by body height of age were found all age groups from 7 to 20 years old and listed in tables from 3-b to 16-b. 5. Standard values of physical and nutritional indices (Rohrer index, Kaup index, Vervaeck index and Pelidisi index) by body height of age were found all age groups from 7 to 20 years old and listed in tables from 3-c to 16-c.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.303-318
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• 2014

Baseflow gives a significant contribution to stream function in the regions where climatic characteristics are seasonally distinct. In this regard, variable baseflow can make it difficult to maintain a stable water supply, as well as causing disruption to the stream ecosystem. Changes in land use can affect both the direct flow and baseflow of a stream, and consequently, most other components of the hydrologic cycle. Baseflow estimation depends on the observed streamflow in gauge watersheds, but accurate predictions of streamflow through modeling can be useful in determining baseflow data for ungauged watersheds. Accordingly, the objectives of this study are to 1) improve predictions of SWAT by applying the alpha factor estimated using RECESS for calibration; 2) estimate baseflow in an ungauged watershed using the WHAT system; and 3) evaluate the effects of changes in land use on baseflow characteristics. These objectives were implemented in the Gapcheon watershed, as an ungauged watershed in South Korea. The results show that the alpha factor estimated using RECESS in SWAT calibration improves the prediction for streamflow, and, in particular, recessions in the baseflow. Also, the changes in land use in the Gapcheon watershed leads to no significant difference in annual baseflow between comparable periods, regardless of precipitation, but does lead to differences in the seasonal characteristics observed for the temporal distribution of baseflow. Therefore, the Guem River, into which the stream from the Gapcheon watershed flows, requires strategic seasonal variability predictions of baseflow due to changes in land use within the region.