• Applied Microscopy
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• v.37 no.2
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• pp.93-102
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• 2007

Secretory leukocyte protease inhibitor (SLPI) was known as one of bacterial lipopolysaccharide (LPS)-induced products of macrophage. Macrophages play an important role in the development of inflammatory responses by secreting an array of cytokines and chemokines in a tissue microenvironment. To identify the function and relationship between potent growth factors and SLPI after LPS stimulation, we conducted reverse transcriptase polymerase chain reaction (RT-PCR) and Western blots for the detection of mRNA and protein expression of SLPI and growth factors such as VEGF, PDGF, bFGF after 100 ng LPS stimulation on the RAW264.7 cells. The result of RT-PCR was showed SLPI mRNA expression was increased from 60 min to 48h in RAW 264.7 cells after incubation with LPS. VEGF and PDGF mRNA was expressed highly at initial stage by LPS stimulation. The mRNA of bFGF and type I collagen was very weakly expressed after LPS stimulation. SLPI protein level was increased likely the mRNA levels in RAW 267.7 cells. Additionally, phase contrast and scanning electron microscopic observation demonstrated that the LPS induce the change of morphology of the RAW264.7 cells. From these results, it suggest that expression of SLPI by LPS treatment may associate with VEGF and PDGF expression in RAW264.7 cells.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.1
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• pp.109-139
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• 2004

The first successful sustained powered flight by Wright Brothers was further extended to the rapid development of aviation technology, that led to transpacific flights, the invention of supersonic planes, and enabled hundreds of people to travel in the space, in addition to the fact that around 10 people had stepped on the moon, all of which were made possible within the very same century. However, on the back side of this most wondrous human technology, the vulnerableness to the aviation accident has been constantly accompanied with, right from the very beginning stage of the aircraft development. Moreover, the development of future aircraft is being focused on the aircraft performance, the increment of the number of passengers aboard and also its speed. In proportion to these phenomena of mega sizing the aircraft, the development of new technology and the increment of air traffic volume, the number of aviation accident is expected to augment, resulting in the enormous loss of human lives and properties. In order to prevent the disastrous aviation accident as such, it is essential to conduct the accident investigation in a specialized, systematic and scientific manner. In search for the method to attain the effective function of the aviation accident investigation organization, in this study, issues were examined as follows: The full-time Board Members and the establishment of an integrated investigation agency, The systematized security of status as an accident investigator, Inclusion of a human factors specialist in the investigator group organization, liability limit of an accident investigator Stipulation of the definition and the investigation scope of an accident and serious incident, along with the main body of conducting the investigation into the accident involving both civil and public aircraft, in the regulations related to the accident investigation.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.73-80
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• 2007

Biofilm media was equipped in two-compartmented wastewater treatment bioreactor which was separated by porcelain septum. DC 2.0 volt of electric potential was charged to anodic (oxidative) biofilm media (ABM) to induce oxidation potential but not to that of carbon (neutral) biofilm media (CBM) that was used for control test. Biofilm structure, biomass variation, Off variation and wastewater treatment efficiency in the bioreactor equipped with ABM (ABM-bioreactor) and CBM (CBM-bioreactor). Time-coursed variation of biofilm structure forming on surface of ABM and CBM was observed by scanning electron microscopy. The biofilm growing on ABM was dispersed on surface and was not completely covered the media but the biofilm growing on CBM was continuously increased and finally covered the media. The ORP of CBM was decreased to 100 mV, which was reciprocally proportional to the biomass growth. However, the ORP of ABM was about 800 mV, which was maintained during operation for about 60 days. The treatment efficiency of COD in the ABM bioreactor was 2 times higher than those in the CBM bioreactor. From these results, we proposed that electrochemical oxidation potential charged to biofilm media may inhibit formation of biofilm extremely condensed and activate bacterial cell metabolism.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.8-15
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• 1984

This study reflects our conviction that the maintenance of the landscape plants in apartment housing areas has appeared as an important factor. The defects ratio of the landscape plants shows high in the study, which tells us a serious situation were facing in consideration of the quality of residential Life. Methods for the effective maintenance of the landscape plants are recommended as follows; First, the landscape plants in apartment housing areas should be maintained by a specialist in landscape architecture. Second, the co-operative maintenance between inhabitants and specialists is required. Third, the over-all understanding of the landscape plants should be improved.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.1
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• pp.90-97
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• 2010

In this paper, we propose antenna topology and ground plane shape to improve the performance of PIFA (Planar Inverted F Antenna) which is built-in mobile phone. First, we designed the PIFA antenna consists of multiple radiators to provide multi-current paths. Then we designed U-shaped ground plane on the PCB under the antenna. The proposed antenna structure shows TRP/TIS improvement of 2.0 dB/3.7 dB for GSM and 2.2 dB/ 2.0 dB for DCS and 0.8 dB/1.5 dB for PCS and 1.3 dB/0.7 dB for WCDMA at the free space.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.271-273
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• 2003

최근에 전력선통신(PLC: power line communication)에 관한 연구 및 개발이 활성화되고 있는 가운데, 정부에서는 전력선통신을 위한 전송채널의 주파수허용범위를 기존의 협대역인 450kHz에서 광대역인 30MHz로 확대할 계획이다. 현재, PLC 시스템에서는 대용량정보를 고속으로 전송하기 위한 고속 PLC기술의 개발이 활발히 진행되어지고 있으며, 이러한 통신시스템 기술의 구현을 위해서는 새롭게 확대될 30MHz대역에서의 전력선채널의 분석이 무엇보다도 중요한 해결 과제라고 할 수가 있을 것이다. 전력선은 각종 전기기기와 가전제품 및 사무기기로부터 발생되는 잡음들이 직접 유입되며, 또한 부하가 전력선에 연결되는 시간과 공간에 따라 전송 특성이 수시로 가변하는 특성을 가진다. 이와 같은 열악한 전력선통신채널 환경을 극복하고 통신의 에러극복능력을 향상시키기 위해서는 기존의 협대역 채널모델을 그대로 적용하기에는 부적합한 면이 많으므로, 새롭게 허용될 광대역 주파수를 갖는 전력선 채널에 대한 모델링기법이 요구된다. 따라서, 새롭게 인가될 광대역 채널을 위한 효율적인 전력선통신시스템을 개발하기 위해서는 전력선채널의 리모델링에 근거한 다양하고 실험적인 고찰이 수반되어야 하리라고 판단된다. 그러므로, 본 논문에서는 Mixture 잡음 모델링기법을 이용하여, 부하변동 및 가변적인 잡음 특성을 가진 전력선채널모델을 새롭게 분석하였다. 또한, 새롭게 분석한 전력선채널모델에 관한 수식을 직교 코드에 의한 다중접속 통신 기술인 CDMA 방식에 적용하여 비트 에러율을 유도해 봄으로써 그 유효성을 확인하였다.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.63-70
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• 2021

Using computer-aided design and manufacturing technique improve quality of treatment in many aspect. This case reports the complete mouth rehabilitation of a patient with amelogenesis imperfecta utilizing digital technology. Clinical examination revealed loss of mastication due to insufficient occlusal stop, missing teeth, interdental spacing due to microdontia, insufficient overbite, and etc. Full veneer crowns for teeth were selected, followed by a fixed partial denture and implant placement was done using CAD-CAM guide template with bone graft for partially edentulous space. Definitive restorations were duplicated by double scanning provisional restorations and successfully delivered to the patient. These full mouth rehabilitation procedures resulted in satisfactory outcomes for the patient functionally and aesthetically.

• Journal of the Korean association of regional geographers
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• v.20 no.2
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• pp.189-205
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• 2014

Most local governments make an attempt to attract tourists through the large-scale development projects or regional festival events. But, its possibility of success is actually low, so they must take care of ecotourism industry which has higher efficiency in comparison with investing expense. Seocheon area couldn't be focused greatly in spite of the excellent ecological and cultural resources. However, there are lots of possibilities to be a new center of ecotourism because of newly opened National Institute of Ecology and National Marine Biology Resource Institute. Therefore, the purposes of this thesis are to analyze several eco-cultural property all over Seocheon, introduce ecotourism, a main function of ecosystem services, and develop the program satisfying 3 elements of ecotourism; natural environment, visitors and residents. In Seocheon located in where the sea meets the river, ecological property could be reorganized into 4 areas in relation to existing famous tourist attractions. As a measure to let visitors stay, we induced them to lodge in the region through the field work. To realize slow life, we designed it so that they can enjoy each landscape slowly. we also suggested the program which can guide visitors onto the vicinity of habitat for migratory birds at the mouth of Geumgang River and Seocheon foreshore nominated as Ramsar wetlands by focusing on National Institute of Ecology and National Marine Biology Resource Institute which will be the Mecca of ecology research. Through this research, there will be an opportunity to satisfy visitors of Seocheon and enrich local residents' lives.

• Journal of Korea Water Resources Association
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• v.42 no.7
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• pp.537-546
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• 2009

Determination of optimal pressure monitoring location is essential to manage water distribution system efficiently and safely. In this study, entropy theory is applied to overcome defects of previous researches about determining the optimal sensor location. The previous studies required the calibration using historical data, therefore, it was difficult to apply the proposed method in the place where the enough data were not available. Also, most researches have focused on the locations to minimize cost and maximize accuracy of the model, which is not appropriate for the purpose of maintenance of the water distribution system. The proposed method in this study quantify the entropy which is defined as the amount of information calculated from the pressure change due to the variation of discharge. When abnormal condition is occurred in a node, the effect on the entire network is presented by the entropy, and the emitter is used to reproduce actual pressure change pattern in EPANET. The optimal location to install pressure sensors in water distribution system is the nodes having the maximum information from other nodes. The looped and branched networks are evaluated using the proposed model. As a result, entropy theory provides general guideline to select the locations to install pressure sensors and the results can be used to help decision makers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.300-307
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• 1997

The effects of Aster scaber and Ixeris dentata on cadiovascular system in hyperlipidemic rats were examined. Five groups of thirty Sprague Dawley rats were fed with the diet contained 1% cholesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard(control group) for 4 weeks. Each experimental diet group was added with 5% plant powder or extract of the 5% plant powder by dry weight. Contractile or relaxation responses in the isolated artria and thoracic aortae were measured and the morphological changes of the aortic endotherium from the rats fed the experimental diet were inspected. In response to isoproterenol, the number of right atrial spontaneous beat was significantly lower in Cham chyi powder group$(PP_{1})$ and Sumbagui powder group$(PP_{2})$ than control at $10^(-8)M$ concentration. The contraction forces by injection of phenylephrine and calcium in isolated thoracic aorta were significantly low in each experimental groups compared with the control. The relaxation rates by acetylcholine represented comparatively higher value in $PP_{1}$ than control. The morphological changes of endothelial cell surface was a little in $PP_{1}$ and $PP_{2}$ compared with control, while the damages were considerably advanced in Cham chyi and Sumgbagui extract diet group$(PE_{1},\;PE_{2})$.