• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1877-1884
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• 2017

Mesenchymal stem cells (MSCs) have been suggested as a primary candidate for cell therapy applications because they have self-renewal and differentiation capabilities. Although they can be expanded in ex vivo system, clinical application of these cells is still limited because they survive poorly and undergo senescence or apoptosis when transplanted and exposed to environmental factors such as oxidative stress. Thus, reducing oxidative stress is expected to improve the efficacy of MSC therapy. The milk protein lactoferrin is a multifunctional iron-binding glycoprotein that plays various roles, including reduction of oxidative stress. Thus, we explored the effect of lactoferrin on oxidative stress-induced senescence and apoptosis of human MSCs (hMSCs). Measurement of reactive oxygen species (ROS) revealed that lactoferrin inhibited the production of hydrogen peroxide-induced intracellular ROS, suggesting lactoferrin as a good candidate as an antioxidant in hMSCs. Pretreatment of lactoferrin suppressed hydrogen peroxide-induced senescence of hMSCs. In addition, lactoferrin reduced hydrogen peroxide-induced apoptosis via inhibition of caspase-3 and Akt activation. These results demonstrate that lactoferrin can be a promising factor to protect hMSCs from oxidative stress-induced senescence and apoptosis, thus increasing the efficacy of MSC therapy.

• The Journal of the Convergence on Culture Technology
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• v.4 no.3
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• pp.63-74
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• 2018

This study suggested cooperative governance cases and improvement strategies between local welfare centers and urban regeneration support centers, centered on urban revitalization areas around Seoul Station, by applying FGI. Based on the analysis of the contents of FGI participating in the cooperative governance process, it was proved that the common role and identity between the local welfare center and the urban regeneration support center were regional based activities. And the advantage of constructing collaborative governance was analyzed by four ways. In addition, this study presented improvement strategies from a microscopic and macro perspective. The results of this study suggest that the change in the curriculum of social workers' education and the expansion of the scope of the practitioner in the Urban Regeneration Business Act propose.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.3
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• pp.423-436
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• 2016

In a densely developed metropolitan area, the subway system is often constructed to address the mobility problems. Subway system was first introduced in Seoul in late 1970s, then Korean metropolitan cities began to adopt the system later. Subway systems not only resolve the mobility problems, but also interact with regional socioeconomic landscape. This study aims to find the association between the subway network and land rent within the subway catchment areas in Gwangju metropolitan city in a spaciotemporal framework. The analysis results indicated that proximity to the subway station and the size of nearest road were positively associated with the land rent. Also from a cluster analysis, it was found that the old and new Central Business Districts as well as stations at peripheral areas had distinctive land rent change characteristics. This empirical analysis indirectly proves the strong association between land rent and urban planning and also the positive relationship between land rent and transportation networks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.1861-1870
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• 2013

A climate change-driven increased hydrological variability has been widely acknowledged over the past decades. In this regards, rainfall simulation techniques are being applied in many countries to consider the increased variability. This study proposed a Homogeneous Hidden Markov Chain(HMM) designed to recognize rather complex patterns of rainfall with discrete hidden states and underlying distribution characteristics via mixture probability density function. The proposed approach was applied to Seoul and Jeonju station to verify model's performance. Statistical moments(e.g. mean, variance, skewness and kurtosis) derived by daily and seasonal rainfall were compared with observation. It was found that the proposed HMM showed better performance in terms of reproducing underlying distribution characteristics. Especially, the HMM was much better than the existing Markov Chain model in reproducing extremes. In this regard, the proposed HMM could be used to evaluate a long-term runoff and design flood as inputs.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.249-260
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• 2012

Monitoring of climate change and atmospheric environment by satellite measurements has been increased in recent years. In this study, nitrogen dioxide ($NO_2$) measurements from Ozone Monitoring Instrument (OMI) were compared with surface measurements over the Korean peninsula. $NO_2$ from OMI measurements showed high values and also showed seasonal variations such as high concentration in winter and low in summer over metropolitan areas while $NO_2$ concentration at national background station was low and did not clearly show seasonal variations. Surface measurements showed similar temporal and spatial variations to those of satellite measurement. The comparison between satellite measurements and surface measurements showed that the correlation between them was higher in urban area (r=0.64 at Seoul and r=0.63 at Daegu) than in national background stations (r=0.37 at Jeju) because the concentration in urban area was relatively high so that the variation of $NO_2$ concentration could be detected better than at national background stations by satellite. Satellite can effectively measure the emission and transport of pollutants with no limitations in spatial coverage.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.117-122
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• 2019

City parks play an important role in reducing the air pollution and mitigating the city heat island effect caused by global warming. However, from July 2020, restricted parks over 20-year will be partially lifted due to sunset regulation on parks. As a result, the government and local governments have been making efforts to revitalize parks, such as creating ecological parks and securing park sites. However, building winds generated by high-rise buildings constructed around ecological parks in the city may cause discomfort to pedestrians and threaten the ecosystems of plants and animal that live in ecological parks. There are no clearly proposed as standards for wind environment assessment in Korea, but also it has been rarely studied on pedestrian wind environment. In this study, wind environment studies have been reviewed to find the important parameters related to wind environment assessment. Further, wind climate analysis using wind data obtained by Seoul meterological station was performed to examine the possibility of applicability of the wind environment assessment on the city ecological parks.

• Journal of Korea Water Resources Association
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• v.40 no.8
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• pp.643-654
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• 2007

This study proposes and evaluates a methodology for deriving the rainfall intensity- duration-frequency relationship for durations less than 10 minutes used for designing drainage systems in small urban catchments and roads. The method proposed in this study is based on the Moupfouma distribution, which has been evaluated by applying it to the rainfall data at the meteorological Seoul station. Summarizing the results is as follows: (1) The frequency analysis results using minutely rainfall data was found not to be corresponded with the extrapolation of that by the Ministry of Construction and Transportation (2000). (2) The annual maxima minutely rainfall data derived by applying the Moupfouma distribution to the accumulated 60-minute data was found to well reproduce the characteristics of those of observed. (3) The rainfall intensity-duration-frequency relationship derived by applying the Moufouma distribution to the accumulated 50-minute data and hourly data was found insignificant.

• Archives of design research
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• no.18
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• pp.153-162
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• 1996

underground space have many negative environmental clements which should be confirmed on location and line of action by the artificial signs. iccordingly, environmental graphics as visual language for popular signification-function have to be studied on sign theory of symbolic meanings. Ho\/ever, its usage has not only decorated by microscopiC appreciative eye but also lost its meanlllg as a visual language which was caused by the negligence of systematic management of the facility in charge Result of study, Visual environmental factors as a cause of behavioral attitude based on the study, which has been carefully considered as a communication of the visual language. Therefore, considering the underground environmental graphics as the: sign or the signification-function, It has to be studied on syntactic, semantic and pragmatic viewpoint. SpeCifically, to maKe the color and formation language a signification-function as a generalized connotation to the public, a distinctive classified Visual language must be applied.

• Korean Journal of Microbiology
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• v.1 no.1
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• pp.10-18
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• 1963

Studies with the Tobacco Mosaic Viruses; W. S Kim, and So, I Y., (Dept. of biology Sung Kyun Kwan Univer. Seoul, Korea.). Using the common strain of tobacco mosaic virus (TMV) which was sent from the Dept. of Plant Pathology, University of Wisconsin, U.S.A. as control virus, a possible new strain of tobacco mosaic virus (SMV) was isolated from tobacco leaves collected from Tobacco Experiment Station farms as well as from various blends of manufactured Korean cigaretts. SMV was isolated by single lesion isolation method and by inoculating the virus through various species of host plants. The two viruses, TMV and SMV were indentified by the difference in symptoms, host range, serological reaction, and electron micrograpy. As the results of the above experiment the author believes the virus isolate SMV is a different strain of TMV. The experimental evidences that SMV belongs to the TMV group are as follows; 1. Both viruses produced local necrotic lesions on Nicotiana glutimosa L. 2. Both showed a dilution end point of $10^8$. 3. Aphid transmission was failed with the viruses. 4. Both had an isoelectric point around pH 3.3. 5. Two viruses were serological reactive. 6. The size of the virus particles was around 270-300mu as they were observed under the electron microscope. The virus SMV, however, is different from the common strain of TMV and the experimental evidences are as follows; 1. SMV produced quite different symptoms from TMV on various host plants like tobacoo(Nicotiana tabacum L., White Burley), Nicotiana rustica L., Chenopodium Koreanse Nakai. Bata vulgaris L., and Datura tatula L., SMV produced distinct local lesions on these host plants whereas TMV incited largely mosaic diseases. 2. The serological titers obtained from the heterologous combinations were lower than those from homologous combinations of antigens and antiser.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.6
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• pp.357-364
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• 2014

In this paper deals with PON Remote monitoring solution using Reflecting Filter. The current FTTH-PON can not be monitored in real time that Optical cable fault and Quality degradation of Splitter. To solve this problem, Monitoring can make Feeder Network and Splitter that Reflecting filter development using the basic structure of Fiber Bragg grating. Reflecting Filter is Quality Monitoring System shall provide tools for user to view and analyze degradation of cables and splitter in particular predict any gradual component degradation(Optical cable bending, splice, connector, etc) before it becomes service impacting. The Reflecting Filter solution is splitter down and confirm the fault location of optical cable and it will send central control station can be monitored system an alarm to the OLT. In other words, wavelength side branches Mating existing communication affairs (Coupler) using the core of one optical wavelength for live monitoring two wavelengths and sends the subscriber side modem and aggregation switch device remotely using a reflective optical line filter monitoring the study of the system. this study can development of Reflecting filter improve the average processing time of Optical cable fault and efficient Maintenance of the network.