• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.571-580
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• 2012

Epidemiologic studies of air pollution need accurate exposure assessments at unmonitored locations. A land use regression (LUR) model has been used successfully for predicting traffic-related pollutants, although its application has been limited to Europe, North America, and a few Asian region. Therefore, we modeled traffic-related pollutants by LUR then examined whether LUR models could be constructed using a regulatory monitoring network in Metropolitan area in Korea. We used the annual-mean nitrogen dioxide ($NO_2$) in 2010 in the study area. Geographic variables that are considered to predict traffic-related pollutants were classified into four groups: road type, traffic intensity, land use, and elevation. Using geographical variables, we then constructed a model to predict the monitored levels of $NO_2$. The mean concentration of $NO_2$ was 30.71 ppb (standard deviation of 5.95) respectively. The final regression model for the $NO_2$ concentration included five independent variables. The LUR models resulted in $R^2$ of 0.59. The mean concentration of $NO_2$ of elementary schools was 34.04 ppb (standard deviation of 5.22) respectively. The present study showed that even if we used regulatory monitoring air quality data, we could estimate $NO_2$ moderately well. These analyses confirm the validity of land use regression modeling to assign exposures in epidemiological studies, and these models may be useful tools for assessing health effects of long-term exposure to traffic related pollution.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.215-220
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• 2012

This paper proposes a ontology of tree structure approach for adaptive object recognition in a situation-variant environment. In this paper, we introduce a new concept, ontology of tree structure ontology, for context sensitivity, as we found that many developed systems work in a context-invariant environment. Due to the effects of illumination on a supreme obstinate designing context-sensitive recognition system, we have focused on designing such a context-variant system using ontology of tree structure. Ontology can be defined as an explicit specification of conceptualization of a domain typically captured in an abstract model of how people think about things in the domain. People produce ontologies to understand and explain underlying principles and environmental factors. In this research, we have proposed context ontology, context modeling, context adaptation, and context categorization to design ontology of tree structure based on illumination criteria. After selecting the proper light-ontology domain, we benefit from selecting a set of actions that produces better performance on that domain. We have carried out extensive experiments on these concepts in the area of object recognition in a dynamic changing environment, and we have achieved enormous success, which will enable us to proceed on our basic concepts.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.5
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• pp.11-21
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• 2009

Considering that the weight of a biaxial hollow slab system is not increased with an incremental increase in its thickness, and that the flexural stiffness of a biaxial hollow slab is not significantly lower than that of a general solid slab, there has been a growing need for biaxial hollow slab systems, because long span structures are in great demand. In a long span structure, the problem of vibration of floor slabs frequently occurs, and the dynamic characteristics of a biaxial hollow slab system are quite different from the conventional floor systems. Therefore, in this study, the floor vibration of a biaxial hollow slab system subjected to walking load is investigated in comparison with a conventional floor slab system. For the efficiency of time history analysis, an equivalent plate slab model that can precisely represent the dynamic behavior of a biaxial hollow slab system is used. From the analytical results, it was determined that vibration of a biaxial hollow slab system subjected to walking load is evaluated as "office-level vibration," according to the classifications of the architectural institute of Japan and ANSI.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8870-8878
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• 2015

During the carbon-dioxide capture and storage(CCS) process, $CO_2$ is captured from large point source, and then injected and stored in stable geological structure for thousands and more years. Inside the captured $CO_2$ flow, various impurities, such as $N_2$, $O_2$, argon, etc, are included inevitably. These impurities affect on the CCS process on various aspects. In this study, we designed and built experimental facility to evaluate the various impurity effect on the $CO_2$ pipeline flow, and analyzed the effect of argon ratio and pressure variation on the pressure drop of $CO_2$ flow. By comparing experimental data with 4 kinds of pressure drop model, we figured out and recommended the Cicchitti's model since it showed most accurate result among compared models in this study.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.5
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• pp.511-520
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• 2007

There is a concern with worldwide deterioration of highway bridges, particularly reinforced concrete. The advantages of fibre reinforced plastic(FRP) composites over conventional materials motivate their use in highway bridges for replacement of structures. Recently, an FRP deck has been installed on a state highway, located in New York State, as an experimental project. In this paper, a systematic approach for analysis of this FRP deck bridge is presented. Multi-step linear numerical analyses have been performed using the finite element method to study the structural behavior and the possible failure mechanism of the FRP deck-superstructure system. Deck's self-weight and ply orientations at the interface between steel girders and FRP deck are considered in this study. From this research, the results of the numerical analyses were corroborated with field test results. Analytical results reveal several potential failure mechanism for the FRP deck and truss bridge system. The results presented in this study may be used to propose engineering design guideline for new and replacement FRP bridge deck structure.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.663-667
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• 2010

Experiments were undertaken to assess the antinociceptive effect of bee venom (BV) in rodent animal models. Comparison of antinociceptive efficacy between Korean BV and commercially available American BV was the primary interest of the study. Korean BV was collected using BV collector devices in which an electrical impulse is used to stimulate the worker bee (Apis mellfera L.) to sting and release venom. After collection, whole BV was evaporated until dry using the BV collector. Commercially available dried American BV was purchased from Sigma Company in USA. Korean and American sourced BVs were diluted and amounts of 6 mg/kg body weight (BW), 0.6 mg/kg BW and 0.06 mg/kg BW were tested. BV was subcutaneously injected to produce an antinociceptive effect and the antinociceptive efficacy was evaluated using a writhing test in mice and a formalin test in rats. The antinociceptive effects of the two BVs tested were similar in mice for visceral pain and showed a dose-dependent response. The antinociceptive effect of Korean BV was not significantly different compare to American BV. These results suggest that Korean BV may be used to achieve an antinociceptive effect for use in medical therapies.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.208-215
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• 2005

This study was accomplished in order to collect fundamental data on microbial roles in recycling process of reed rhizosphere. Sunchon bay, which is considered as one of the marsh and mud environments severely affected by human activities such agriculture and fisheries, was selected as a model place. In our initial efforts, two bacterial consortia were obtained by enrichment culture using PAH mixtures containing anthracene, naphthalene, phenanthrene and pyrene as the sources of carbon and energy, and four pure bacteria capable of rapid degradation of PAH were isolated from them. Four strains designated as SCB1, SCB2, SCB6, and SCB7 revealed by morphological, physiological and molecular analyses were identified as Burkholderia anthina, Alcaligenes sp., Achromobacter xylosoxidans., and Pseudomonas putida, respectively with over $99{\%}$ confidence. Notably, Burkholderia anthina SCB1 and Alcaligenes sp. SCB2 were found to utilize anthracene and pyrene more quickly than naphthalene and phenanthrene, whereas Achromobacter xylosoxidans SCB6 and Pseudomonas putida SCB7 exhibited similar growth and degradation patterns except for pyrene. These facts suggest that the rhizosphere microorganisms capable of PAH degradation might be used to clean up the contamination sites with polycyclic aromatic hydrocarbons.

• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.303-311
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• 1998

Ten reinforced concrete rigid frames and infilled shear wall frames were tested under both vertical and cyclic loadings. Experiments were carried out to evaluate the structural performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. under load reversals. All the specimens were modeledin one-third scale size. Based on the test results reported in this study, the follwing conclusions can be made. For the rigid frame type and the fully rigid babel type shear wall specimens, the hysteresis diagrams indicate that the degradations of their strength were developed slowly beyond maximum carrying capacity. It was shown that when the hoop reinforcement ratio became higher, the energy dissipation capacity became larger and the failure mode became ductile. The specimens designed by the less hoop reinforcement for the fully rigid babel type shear wall, were mainly failed due to diagonal crack in comparison with the specimens designed by the larger hoop reinforcement ratio. Maximum horizontal resisting moment capacity of speciment designed by the fully rigid babel shear wall were increased by 5.47~7.95 times in comparison with the rigid frame type.

• The Journal of Internal Korean Medicine
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• v.32 no.3
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• pp.345-360
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• 2011

Objectives : This study was examined to investigate the effects of Cheonmagudeng-um gagam (CGG) extract on spontaneous hypertension. Methods : For the study of CGG, we divided rats into three groups. The normal group was Wister Kyoto rats (WKY). The control group was spontaneously hypertensive rats (SHR). The treatment group was SHR which were administered CGG extract (SHR-CGG). SHR-CGG were orally administered CGG extract that was diluted in distilled water at the various concentrations for 4 weeks (234.5 mg/kg) and SHR were orally administered the same dosage of plain distilled water as SHR-CGG. Then we measured anti-oxygen effects, ACE inhibitory activity, weight of heart and kidney, blood pressure, heart rate, plasma aldosterone, electrolyte, creatinine, uric acid, BUN, and observed the cortex of the cardiac muscle, kidney, and adrenal gland. Results : CGG increased DPPH scavenging activity and SOD similar activity depending on the concentration. CGG significantly decreased ROS, TNF-${\alpha}$, IL-6, IL-$1{\beta}$, heart weight, blood pressure, heart rate, aldosterone, and BUN in SHR. CGG increased ACE inhibition activity depending on the concentration. CGG inhibited the heart, kidney and adrenal gland tissue injury that is caused by hypertension. Conclusions : These results suggest that CGG is effective in treatment and prevention of hypertension.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.5
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• pp.282-287
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• 2017

The purpose of this study was predicted the effects of mixing and diffusion due to the operation of the apparatus before the development of the mixed diffusion device for the decontamination absorbent to minimize the influence of contaminant inflow due to radiation accident. The tracer used for the flow characteristics was $^{68}Ga$, $^{99m}Tc$, which is a radioactive isotope, and 2 inch NaI radiation detector was used to detect it. The impeller of the decontamination mixed diffusion system applied to this study was made into three types and the mixing diffusion effect was compared. As a result of analyzing the flow characteristics of the radio-isotope with decontamination mixed diffusion device, mixing, diffusion and flow pattern were obtained. The radial mixing type impeller was able to diffuse to the water surface by the upflow flow, and the fin structure was adjusted for finding optimal conditions. The model 3 type consists of a fin guiding part and an auxiliary fin so that the diffusion speed is higher than that of other types of impellers. It also showed a short time to reach complete mixing.