• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8C
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• pp.731-740
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• 2012

To offer indoor location-aware services, the needs for efficient and accurate indoor localization system has been increased. In order to meet these requirement, we presented the BLIDx(Bidirectional Location ID exchange) protocol that is efficient localization system based on sensor network. The BLIDx protocol can cope with numerous mobile nodes simultaneously but the precision of the localization is too coarse because that uses cell based localization method. In this paper, in order to compensate for these disadvantage, we propose the fingerprint overlapping method by modifying a fingerprinting methods in WLAN, and localization system using proposed method was designed and implemented. Our experiments show that the proposed method is more accurate and robust to noise than fingerprinting method in WLAN. In this way, it was improved that low location precision of BLIDx protocol.

• Spatial Information Research
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• v.16 no.1
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• pp.51-64
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• 2008

Recently, development and research of u-City established the ubiquitous environment which can be anytime, anywhere computing or network, has been much highlighted. Thus, current urban facilities should be managed by ubiquitous concept, and monitored location and status information in a real-time manner, and controled if necessary. In order to be establish in the purpose of management, indirect mapping through id-tag is better than facility management directly. For instance, RFID, UCODE, UFID. In this paper, we propose that represent facility object through UOID(Unique Object IDentification). UOID comprises three parts; 1) sensing object, 2) facility object, 3) cell object consists of facilities. and Life cycle management system in UOID, and network system connected with internet is proposed. We wish that proposed UOID and network system mange u-City facilities effectively, and also provide ubiquitous service to the citizen, one of the integrate service of u-City platform.

• Journal of the Korea Society of Computer and Information
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• v.14 no.7
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• pp.73-80
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• 2009

Internet accidents have skyrocketed every year. It always has been threatened by the methods such as hacking and Spyware. The majority of security accident is formed of the loss of authentication information, and the internal user who is not authorized. The importance of security is also emphasized when someone tries to do something accessing to the main information system. Accordingly, Biometrics has been used in many ways. OTP, however, must have a few devices accessing to several systems, and Biometrics involve some risk of mis-recognition rate and mis-denial rate. It also has the risk possible to access to the main information system when losing OTP. This research reduced risks about the loss as separating RFID leader for mobile, Tag and the accessor's cellular phone, and is about pseudo random validation key generated from the administration system through contact with RFID leader for mobile and Tag. As sending the key to user's cell phone which is already registered, security is strengthened more than existing connection methods through the ID and password. RFID for mobile not generalized to the present has been studied as a tool accessing to the main information system.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1977-1983
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• 2006

Kaempferol was isolated and identified from the methanol extract of the flowers of Impatiens balsamina. Kaempferol showed inhibitory activity against mushroom tyrosinase with an $ID_{50}$ of 0.042 mM. Inhibition kinetics, as determined using a Lineweaver-Burk plot, showed kaempferol to be a competitive inhibitor of mushroom tyrosinase with a $K_i$ value of 0.011 mM. The lag phase of tyrosine hydroxylation catalyzed by mushroom tyrosinase clearly increased on increasing the concentration of kaempferol. In addition to its tyrosinase inhibiting activity, kaempferol strongly inhibited melanin production by Streptomyces bikiniensis, in a dose-dependent manner, without inhibiting cell growth. For comparative purposes, the tyrosinase inhibitory activity of kaempferol was also assayed versus quercetin, a positive standard.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.582-586
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• 2005

In this Study, we have attempted to determine the effects of dietary fructose polymers (fructan), high molecular-weight ${\beta}-(2,6)-linked$ levan, and low-molecular-weight ${\beta}-(2,1)-linked$ inulin, on two intestinal enzymes $({\beta}-glucuronidase\;and\;{\beta}-glucosidase)$. As a preliminary experiment, when intestinal microflora were cultured in anaerobic media harboring levan or its oligosaccharides, bacterial cell growth was observed in the levanoligosaccharide-supplemented media, but not in the levan-supplemented media, indicating that levan's size is important for the utilization by intestinal bacteria of levan as an energy Source. In our animal study, the intake of a levan-rich diet was determined to significantly attenuate the activity of the harmful enzyme $({\beta}-glucuronidase$, but d id not affect the activity of ${\beta}-glucosidase$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.spc1
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• pp.169-175
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• 2004

동의보감에 수재되어 있는 약쑥은 식용뿐만이 아니고 한방에서는 출혈 및 지혈약으로 자궁출혈, 임신중의 출혈, 코피지혈 등에 효과가 크다고 알려져 왔다. 또한 부인병과 건위, 설사치료와 항암활성, HeLa cell에 대한 억제작용도 보고되어 있다. MeOH엑스가 HCl-EtOH유발법, $1\%$ 암모니아 수용액 유발법, HCl-aspirin 유발법등에 의하여 유발된 위 손상에 대하여 강한 억제 작용을 나타내고 있는데 이는 flavonoid의 일종인 eupatilin으로 확인된 바 있다. 이 물질이 5-lipoxygenase inhibitor ($ID_{50}=14{\times}16^{-6}M$) 작용과 prosta glandin synthase의 활성을 약간 억제한다고 보고되었다. 약쑥의 eupatilin과 jaceosidin을 분리하여 그 화학구조를 구명하였다. 이를 지표물질로 하여 HPLC 분석조건과 HPLC용 검체의 조제, 표준검량선을 작성하였다. 강화사자발쑥 100 g의 잎에는 eupatilin은 240 mg, jaceosidin은 10 mg함유되어 있고 싸주아리쑥에는 eupatilin은 330 mg, jaceosidin은 123 mg 함유되어 있음이 확인되었다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.92-92
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• 1993

Point mutations in a highly conserved central region of the HIV-1 integrase protein were analyzed for their effects on viral replication and virion morphogenesis. Conservative amino acid replacements of two amino acid residues invariant un retroviral integrases, D116 and E152 of HIV-1, as well as the highly conserved amino acid S147, completely blocked viral replication in two CD4$\^$＋/ human T cell lines. Mutation of four other highly conserved amino acids in the region had no detectable effect on viral replication, while Mutations at two positions, N117 and Y143, resulted in viruses with a delayed replication phenotype. Characteristic and reproducible defects id virion core structure were observed by electron microscopic analysis of sore of the replication defective integrase point mutants, indicating that mutant integrase proteins can interfere with the process of virion core maturation.

• Information and Communications Magazine
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• v.28 no.12
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• pp.50-60
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• 2011

Visible light communication(VLC) is one type of short-range, optical, and wireless communication system utilizing light emitting diode(LED) and laser diode(LD) as optical source. In a VLC system, visible light is used as a transmission medium and used to illuminate. Using VLC has a lot of advantages: it is harmless to human body; it transmits with high power, and it has excellent security, a high data rate, and a license free frequency band. With such a unique blend of communication and illumination in one system, the most common application would be an indoor environment. We aim at reviewing key issues in VLC network such as : FOV(field of view), priority MAC, cooperative MAC, link switching, LED-ID technique, cell site diversity, and link recovery.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06b
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• pp.154-156
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• 2006

핸드폰이나 PDA가 보편화되면서 위치인식 기술의 중요성이 높아졌다. 자동차용 네비게이션, 물류시스템의 상품 운반현황 추적과 같은 상용 서비스들도 활성화되고 있다. 이러한 위치기반 서비스(LBS : Location based service)에서, 보다 개인화된 위치정보를 제공하기 위해서는 지도에 나타나지 않는 개인의 위치를 스스로 학습하고, 인지할 수 있는 시스템이 필요하다. 본 논문에서는 GPS나 Cell ID와 같은 기존 위치 인식 장비로부터 읽혀진 위치데이터를 스스로 학습하여, 사람이 이해하고 사용할 수 있는 장소라는 개념으로 확장하는 시스템을 구축하는 방범에 대해 연구하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.1
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• pp.37-41
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• 2016

Localization is one of the key issues of demandable applications, especially smart services. Beside the traditional GPS based localization technique, the localization issue by visible light communications is promising market because of possibility of combining visible light communications with positioning technique for a high accurate, especially indoor localization service. This paper provides the overview and new image sensor scheme for localization issue based on visible light communication. The survey is introduced from core techniques to enhancement issues of localization. We hope these will be the essential references for the impact selection method in implementation and standardization issues.