• Journal of Korean Society of Environmental Engineers
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• v.35 no.3
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• pp.192-199
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• 2013

The Tandong-cheon stream is a 7.4 km long small urban stream that passes through Daeduk Science Town in Daejeon Korea. Despite the stream has great potential as an educational and recreational site due to its central location in the science town and science museums nearby, environmental aspect especially for water quality has not been evaluated properly. Through field survey, major pollution sources of the stream were identified and effect of water quality improvement alternatives were evaluated using a QUAL2K water quality model for the stream. The study indicated that controlling major pollution sources of the stream alone may not be sufficient for reaching the water quality target. Therefore, additional pollution control methods are necessary. We applied the developed model to evaluate the effects of a constructed wetland on the terrace land, and analyzed whether the water quality target can be met at the outlet of the stream. It is expected that this study would provide a good reference for environmentally sound management of small urban streams in Korea.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.432-438
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• 2010

This study was carried out to understand the effect on soil chemical property, ion contents, and growth of Lonicera japonica by treatment of simulated acid rain and wood vinegar. It was treated total 30 times by one time per 2 weeks during 150 days from June to October dividing to various pH level of simulated acid rain (each pH 5.6, 4.5, 3.5 and 2.5) and the control site (pH 6.3). The wood vinegar diluted with 500 times was also treated total 10 times by one time per 2 weeks at the experimental sites. The soil pH was reduced as pH level of simulated acid rain was decreased. The organic content, total nitrogen, and Av. $P_2O_5$ in soil showed a tendency to increment. However, the soil improvement effect was exposed to be insufficient when a wood vinegar was treated. In the component of the plant body, $SO_4{^2}$ and $NO_3{^-}$ increased due to the simulated acid rain treatment and the increment ratio was reduced in the wood vinegar treatment plot. In addition, the cation contents showed a tendency to variation due to pH of simulated acid rain. And it showed more increment in the leaves than the root. The early fallen leaves and growth inhibition of L. japonica showed up after the simulated acid rain treatment but the growth of L. japonica increased after the wood vinegar treatment.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.217-227
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• 2018

The objective of this study is to analyze the effects of music lesson applying the blended learning-based STEAM education on the musical knowledge and STEAM literacy of pre-service kindergarten teachers. After conducting a pre-test on the musical knowledge and STEAM literacy targeting 20 students(3rd year) of early childhood music lesson in Dept. of Early Childhood Education of C University in O Metropolitan City and 19 students(3rd year) of early childhood music lesson in Dept. of Early Childhood Education of D University in B Metropolitan City, the effectiveness of the pre - post test design was verified. In the results of study, the experimental group with music lesson applying the blended learning-based STEAM education showed significantly improved results in all the areas of musical knowledge and convergence, creativity, and communication out of STEAM literacy than the control group with general music lesson. Such results of this study imply that music lesson applying the blended learning-based STEAM education could be usefully used as a teaching/learning method to improve musical knowledge and STEAM literacy of pre-service kindergarten teachers in university education site in the future.

• Journal of Korean Foot and Ankle Society
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• v.23 no.4
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• pp.173-182
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• 2019

Purpose: This study determined if anterior talofibular ligament (ATFL)/superior extensor ankle retinaculum (SEAR) thicknesses are related to dynamic balance in individuals with chronic ankle instability (CAI). Materials and Methods: The subjects were 14 males and 15 females (age=24.52±3.46 years). Ankle instability was assessed using the Cumberland Ankle Instability Tool (CAIT) with a cut off score of 25 to define two groups. SonoSite MTurbo (Fugifilm Sonosite, Inc.) musculoskeletal ultrasound (MSKUS) unit was used to assess ATFL and SEAR thicknesses. Dynamic balance was measured with the Y Balance Test (YBT) and two NeuroCom balance tests. Results: There were no significant differences in the average ATFL thickness between stable and unstable ankles in those subjects with CAI (0.25±0.03 cm and 0.21±0.05 cm, respectively) or in the SEAR thickness (0.09±0.04 cm and 0.10±0.03 cm, respectively). There were also no significant differences in the right and left ATFL thicknesses (0.23±0.07 cm and 0.21±0.04 cm, respectively) or the SEAR thicknesses (0.09±0.01 cm and 0.09±0.01 cm, respectively) in those without CAI. There were no differences between limbs in composite scores on YBT in those with CAI (p=0.35) and those without CAI (p=0.33). There was a moderate correlation between the left SEAR thickness and the large forward/backward perturbations on the NeuroCom (Natus) motor control test (r=0.51, p=0.006 and r=0.54, p=0.003, respectively). Conclusion: There were no differences in the ATFL/SEAR thicknesses or balance measures between or within the groups, likely because CAI is multi-factorial and related to mechanisms other than tissue changes alone. More sensitive technology and a better definition of the measurement process may provide more definitive results.

• Journal of the Korean Electrochemical Society
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• v.3 no.4
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• pp.204-210
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• 2000

The control of dissolved aluminum concentration in the hot dip zinc galvanizing bath is greatly important in producing galvannealed steel sheets. The purpose of present study is to provide basic data for measurement of the aluminum concentration in site in hot dip zinc bath at the temperature of $460^{\circ}C\~500^{\circ}C$ using $CaF_2$ solid electrolyte sensor with three kinds of reference electrode. Good workability and stability of the sensor were confirmed with the $Bi+BiF_3$ reference electrode from the emf measurement. In order to measure the aluminum concentration in Zn-Al bath, the galvanic cell of fluorine ion was constructed with $CaF_2$ solid electrolyte as follows; $$(-)W|Zn-Al,\;AlF_3|CaF_2|Bi,BiF_3|W(+)$$. The emf measurement was made at the temperature of $460\pm10^{\circ}C$ in the Zn-Al bath. The following correlationship between aluminum concentration and emf was obtained by the least square regression analysis; $$E/mV=56.795log[\%Al]+1881.7\;R=0.9704$$,$$0.026wt\%{\leq}[\%Al]{\leq}0.984wt\%$$

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.332-344
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• 1999

Cytokines are hormone-like proteins which mediate and regulate inflammatory and immune responses. Interleukin-6 (IL-6) is involved in the final differentiation of B cells into antibody-producing cells. Interleukin-8 (IL-8) is a neutrophil chemotactic factor that plays an important role in the recruitment of neutrophil to inflammatory loci. Inflammatory mediators by cells in the gingiva have been implicated in the initiation and progression of periodontitis and oral infection. The purpose of this study was conducted to investigate the effect of lipopolysaccharide (LPS), staphylococcus enterotoxin B (SEB) on production of IL-6 and IL-8 by human gingival and facial dermal fibroblasts. Primary cultured human gingival and facial dermal fibroblasts were incubated with LPS (0.01, 0.1, $1.0{\mu}g/ml$), SEB (0.01, 0.1, $1.0{\mu}g/ml$) or LPS $(0.1{\mu}g/ml)$ plus SEB $(0.1{\mu}g/ml)$. Culture supernatants were collected at 24, 48, and 72 hrs and assessed for IL-6 and IL-8 production by enzyme-linked immunosorbent assay. IL-6 production in gingival fibroblasts stimulated with LPS was higher than that with SEB. IL-6 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-6 production in facial dermal fibroblasts was increased only by stimulation with a high concentration of LPS $(1.0{\mu}g/ml)$. Its production in facial dermal fibroblasts by exposure with SEB was decreased in comparison with control, nontreated cells. Therefore, gingival fibroblasts showed higher sensitivity than facial dermal fibroblasts in response to low concentration of LPS. Also, IL-6 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-8 production in gingival fibroblasts was enhanced greatly only by stimulation of high concentration of LPS $(1.0{\mu}g/ml)$. That by exposure with SEB was increased only in 24 hrs cultivation. IL-8 production by double exposure with LPS plus SEB was amplified in comparison with single exposure of LPS or SEB. IL-8 production in facial dermal fibroblasts was decreased by LPS and increased only in 48 hrs cultivation by SEB. IL-8 production by double exposure with LPS plus SEB was enhanced only in 48 hrs cultivation in comparison with single exposure of LPS or SEB. therefore, IL-6 and IL-8 production were released at various quantities according to bacterial toxin applied and site of fibroblast harvested. These results suggest that gingival fibroblasts may be concerned with IL-6 and IL-8 related inflammatory response more than facial dermal fibroblasts.

• International Journal of Oral Biology
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• v.36 no.3
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• pp.117-122
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• 2011

Endothelial cells are a vital constituent of most mammalian organs and are required to maintain the integrity of these tissues. These cells also play a major role in angiogenesis, inflammatory reactions, and in the regulation of thrombosis. Angiogenesis facilitates pulp formation and produces the vessels which are essential for the maintenance of tooth homeostasis. These vessels can also be used in bone and tissue regeneration, and in surgical procedures to place implants or to remove cancerous tissue. Furthermore, endothelial cell regeneration is the most critical component of the tooth generation process. The aim of the present study was to stimulate endothelial regeneration at a site of acute cyclophosphamide (CP)-induced endothelial injury by treatment with human umbilical cord-derived endothelial/mesenchymal stem cells (hEPCs). We randomly assigned 16 to 20-week-old female NOD/SCID mice into three separate groups, a hEPC ($1{\times}10^5$ cells) transplanted, 300mg/kg CP treated and saline (control) group. The mice were sacrificed on days 5 and 10 and blood was collected via the abdominal aorta for analysis. The alanine transaminase (ALT), aspartate aminotransferase (AST), serum alkaline phosphatase (s-ALP), and albumin (ALB) levels were then evaluated. Tissue sections from the livers and kidneys were stained with hematoxylin and eosin (HE) for microscopic analysis and were subjected to immunohistochemistry to evaluate any changes in the endothelial layer. CP treatment caused a weight reduction after one day. The kidney/body weight ratio increased in the hEPC treated animals compared with the CP only group at 10 days. Moreover, hEPC treatment resulted in reduced s-ALP, AST, ALT levels compared with the CP only group at 10 days. The CP only animals further showed endothelial injuries at five days which were recovered by hEPC treatment at 10 days. The number of CD31-positive cells was increased by hEPC treatment at both 5 and 10 days. In conclusion, the CP-induced disruption of endothelial cells is recovered by hEPC treatment, indicating that hEPC transplantation has potential benefits in the treatment of endothelial damage.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.701-705
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• 2002

This paper describes implementation of IPv6-IPv4 transition toolbox named as 6TALK(IPv6 TrAansLator of Krv6) and some scenarios using 6TALK which enables IPv6 island to connect other IPv6 island or IPv4 island seamlessly. 6TALK implements some transition mechanisms suggested in NGTrans Working Group of IETF. Those mechanisms are composed of basic mechanism, tunneling, and applied mechanism such as DSTM. 6TALK provides functions which enable IPv6 network at the edge of existing network to communicate with IPv4 network by using these transition mechanisms. As major transition mechanisms in 6TALK we adopt NAT-PT/SIIT and DSTM/DSTM options and as implementation environment we use Linux Kernel 2.4.18 and Netfilter framework. Software modules implemented in Linux kernel was ported to hardware box using Motorola MPC 8260 processor. The transition mechanisms used in 6TALK are the ones predicted to be used in initial transition step to IPv6.

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.413-424
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• 2014

Objectives: The purpose of this study was to seek measures for improvement and management of farm work safety and health by conducting questionnaire surveys and on-site investigations to ascertain the present state of occurrence of safety accidents and safety and health management levels among swine farmers. In particular, the purpose of this study is to provide basic data for the establishment of measures for the management of safety and health suitable to the characteristics of related working environments. Methods: Questionnaire surveys were conducted among 223 farmers engaged in swine farming in 14 regions, and 10 farms were visited in order to implement multilateral methods, including in-depth interviews, along with field surveys. Results: The surveys indicated that 26.2% of all respondents experienced farm-work related safety accidents and body-reaction related accidents showed a high ratio at 31.1% of all respondents. With regard to cause materials of safety accidents, work other than that directly related to swine raising showed high ratios of safety accidents, with pigsty facility related accidents at 26.6%. Although most workers recognized the dangers latent in the working environments, their behavior and responses to the prevention of safety accidents were still insufficient due to a lack of understanding of safety and health management. In the survey on the present state of personal hygiene and wearing of protective equipment, workers were found to have been exposed to dangerous and harmful environments both inside and outside pigsties, but the actual states of their wearing protective safety equipment were very poor. Conclusion: Given the results of this study, swine farmers well recognize problems in their control of safety accidents and management of safety and health, but their knowledge about safety and health education and management guidelines was insufficient. Therefore, safety and health education, public relations, and customized personal protective equipment suitable for swine raising work should be developed in order to address the foregoing problem.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.125-130
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• 2005

The ecological characteristics of the specialist insect predator, Oligota kashmirica benefica, were investigated for developing artificial rearing method with special interest on the oviposition behavior, the pattern of adult emergence and temperature in storage, and its effect on the density of the citrus red mite, Panonychus citri. Female beetle oviposited eggs mainly, $95\%$ of the eggs, on the bottom of leaves of the yuzu tree, and $91.3\%$ of them were covered with ecdysis skin of the red mites or the feces of themselves. The rate of adult emergence of the beetle rose up to $86.7\%$ when the horticultural media was provided for pupation from $60\%$ when it pupated in upland soil. Most larvae, $88\%$ of them, were found from the surface to the depth of 2 cm in the horticultural media. The optimum temperature for the storage of the adult beetle was found to be $12^{\circ}C$, at this temperature the 96.7, 73.3 and $70.0\%$ of the beetle survived for 10, 20, and 30 days, respectively. The control effect of the citrus red mite was appeared highest by releasing the beetle at the rate of one beetle against 150 mites.