• Title/Summary/Keyword: Protection function

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Availability Performance Analysis of Korean Wide Area Differential GNSS Test Bed (한국형 광역보정시스템 테스트베드 가용성 성능 분석)

  • Yun, Ho;Kee, Chang-Don;Kim, Do-Yoon
    • Journal of Advanced Navigation Technology
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    • v.15 no.4
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    • pp.510-516
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    • 2011
  • For using Global Navigation Satellite System(GNSS) in the civil aviation, it should satisfies the Required Navigation Performances(RNPs) which are defined by International Civil Aviation Organization(ICAO). RNP defines the required accuracy, integrity, availability, continuity of each flight procedure. In order to guarantee user's integrity, user's protection level has to be overestimated. On the other hand, for improving user's availability, user's protection level has to be estimated tightly. Therefore protection level should be estimated as tight as possible while it assuring the user's integrity. This paper describes the current integrity function of Korean WAD GNSS test bed, and predicts the availability performance of Korean WAD GNSS by simulation.

The Efficacy of Sihocheonggan-san (Chaihuqinggan-san) Extract to Improve the Function of Stratum Corneum on Mice Model after Atopic Dermatitis Elicitation. (시호청간산 투여가 아토피 피부염을 유발한 동물모델의 각질층 기능회복에 미치는 영향)

  • Park Min-Chul;Choi In-Hwa
    • The Journal of Korean Medicine
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    • v.25 no.3
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    • pp.137-148
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    • 2004
  • Objectives : To study change of external dermal formation, change of leukocytes in vasculature, change of lipid formation in stratum corneum and distribution of ceramide through administering Sihocheonggan-san (SC) extract on to the control (CON). This study was done through forcing injury to mice's back skin which have lipid protection formation in stratum corneum. Materials and Methods : The CON to which damage was caused intentionally using the external application on the mice's back skin used the SC. The change of leukocytes in vasculature were identified through optima 5.2 and Student's t-test and the results were made into a dermal formation graph. Results : After dispensing SC extract into the CON, dermal injury was decreased. Especially, recover of lipid protection formation, which includes lipid and ceramide in stratum corneum suppressing acute inflammation that some factors are PKC, TNF-α, IL-12B which controlled the secretion of relating inflammatory cytokine, also went onto decrease of angiogenesis, and a decrease of degranulated mast cells was noted. In addition, the decrease of epithelial injury also caused the growth of cells to decrease in stratum basale and cytoclasis. In the vasculature, the leukocytes were also decreased and it could relate to decrease in CON. Conclusions : SC has effect on CON suppressing the dermal injury through recovering of lipid protection formation in stratum corneum.

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Application of a Watershed-Based Land Prioritization Model for the Protection of Drinking Water Reservoir (상수원 보호를 위한 유역기반 토지관리 우선순위 모델 적용)

  • Lee, Jee Hyun;Choi, Ji Yang;Park, Seok Soon
    • Journal of Korean Society on Water Environment
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    • v.20 no.5
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    • pp.397-408
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    • 2004
  • Due to the growing impact of non-point source pollution and limitation of water treatment technology, a new policy of water quality management, called a source protection, is now becoming more important in drinking water supply. The source protection means that the public agency purchases the pollution sensitive area, such as riparian zone, and prohibit locations of point and non-point sources. Many studies have reported that this new policy is more economical in drinking water supply than the conventional one. However, it is very difficult to determine location and size of the pollution sensitive zone in the watershed. In this paper, we presented the scientific criteria for the priority of the pollution sensitive zone, along with a case study of the upstream watershed of the Paldang Reservoir, Han River. This study includes applications of the analytical hierarchy process(AHP) and a watershed-based land prioritization(WLP) model. After major criteria affecting water quality were selected, the AHP and geographic analysis were performed. The WLP model allowed us to include both quantity and quality criteria, using AHP as the multi-criteria method in making decision and reflecting local characteristics and various needs. By adding a travel-time function, which represents the prototype effectively, the results secured adaptability and scientific objectivity as well. As such, the WLP model appeared to provide reasonable criteria in determining the prioritization of land acquisition. If the tested data are used with a validated travel-time and AHP method is applied after further discussion among experts in such field, highly reliable results can be obtained.

Seismic Performance of the Anchor System of Bearing-protection Devices Preventing the Unseating Failure of Bridges (낙교 방지를 위한 받침보호장치의 앵커부 내진성능)

  • Jeong, Hyeok-Chang;Kim, Min-Su;Park, Kwang-Soon;Ju, Hyeong-Seok;Kim, Ick-Hyun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.14 no.6
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    • pp.45-53
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    • 2010
  • The unseating failure of bridges, which is one of the most severe types of damage leading to the loss of transportation function, should be avoided in earthquakes. As a measure of prevention of unseating failure resulting from the failure of bearings, bearing-protection devices are frequently used. They are installed beside the bearings and protect the bearings by resisting a seismic load transmitted from the superstructure. In order to show appropriate seismic performance, the strength of anchors as well as of device bodies should be confirmed. In Korea, they have been installed only according to the design provided by device agents, because a proper design method for the anchors has not been established. In this study the performance of bearing-protection devices with various heights of concrete bed blocks has been investigated experimentally, and a proper design method has been proposed to secure seismic performance.

Synchronized Sampling Structure applied HW/SW platform for LAN-based Digital Substation Protection (LAN 기반 디지털 변전소 보호를 위한 동기 샘플링 구조적용 HW/SW 플랫폼 기술)

  • Son, Kyou Jung;Nam, Kyung-Deok;An, Gi Sung;Chang, Tae Gyu
    • Journal of IKEEE
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    • v.24 no.1
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    • pp.178-185
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    • 2020
  • This paper proposes precise time synchronization-based synchronized sampling structure applied HW/SW platform for LAN-based protection of future digital substations. The integrated software of the proposed platform includes IEC 61850 protocol, IEEE 1588 precision time protocol and synchronized sampling structure. The proposed platform expected to provide a basis of an application of future distributed sensing data-based protection and control methods by providing synchronized measurement among IEDs. The implementation of the proposed HW/SW platform technique was performed using TMDXIDK572 multi-core/multi-processor evaluation module and its time synchronization performance and synchronized sampling function were confirmed through the performance tests.

Design of a New Thermal shut Down Protection Circuit for LED Driver IC Applications (LED 구동회로를 위한 새로운 과열방지회로 설계)

  • Heo, Yun-Seok;Jung, Jin-Woo;Park, Won-Kyoung;Song, Han-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.12
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    • pp.5832-5837
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    • 2011
  • In this paper, we designed a thermal shutdown block for LED applications using a 1 ${\mu}m$ CMOS process. The proposed thermal shutdown protection circuit has been designed with a shut-off temperature of $120^{\circ}C$ and a restart temperature of $90^{\circ}C$ which are suitable conditions for LED driver IC. Also, we got SPICE simulation results of the circuit about process variation of the semiconductor fabrication. From simulation data, process variation rate of the proposed circuit are within 7 % which are good results compared with conventional BJT current mirror type circuit. Finally, we confirmed that the thermal shutdown circuit has good thermal protection function within a LED driver IC.

A Design and Implementation of Interoperable DRM System Based on DMP (DMP 기반의 상호운용 가능한 DRM 시스템 설계 및 구현)

  • Cho, Tae-Beom;Lee, Sang-Jo;Jung, Hoe-Kyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.5
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    • pp.860-867
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    • 2007
  • Digital Contents are increasing the modification of the contents by individual user and the modified or copied contents are simply distributed though the ultrahigh speed internet and the negative pervasive effect on the contents market is increasing. The solutions for copyright protection from illegally distributing contents are developing by various standardization groups and contents manufacturers and its commercia use is partly practiced. The MPEG was developing the IPMP technique to apply existed MPEG standards as a way of digital contents protection. However, as these IPMP techniques did not provide a satisfactory function for contents protection, the DMP standard was suggested as an alternative plan. In this paper, the system is designed and materialized to apply the TooIPack concept of DMP which ensure the interoperability of DRM system. With this paper, it is expected that the practical use and the possibility of the DMP standard in the DRM market would be verified and DMP standard may presents as a reference model for more systematic standardization operations.

The standardization and R&D directions on contents protection technology in UHD broadcasting (UHD방송 콘텐츠 보호기술 개발 및 표준화 추진 방향)

  • Min, J.H.;Koo, H.S.
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.638-641
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    • 2016
  • UHD(Ultra High Definition) broadcasting is an attractive next-generation service of realistic broadcasting that enables you to feels like listening on the spot in ultra-high definition resolution. In addition, the test broadcasting run by UHD broadcasting agencies and UHDTV terminal launch could herald the full-scale UHD broadcasting era. However, in order that UHD broadcasting will be activated, the function of conditional access control and information protection through which we can on pay per view watch the programs of subscriber preference from the channels of various and subdivided genres is essential. To provide a technical foundation for these features and to achieve the UHD TV transition early, determining technology development & standardization strategy through the analysis of the key protection technologies is required In this paper, we propose standardization technologies which our country can lead and present a long-term driving directions by analyzing UHD broadcasting technology & test broadcasting trends and content protection technology & standardization trends.

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A Study on Determination of Optimal Reclosing Guideline on Distribution Lines (배전선로 재폐로 최적 기준 산정에 관한 연구)

  • Cho, Jae-Hun;Lee, Sun-Jung;Moon, Chae-Joo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.3
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    • pp.417-422
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    • 2022
  • It is always desirable that the continuation of power flow through the lines should not be interrupted for a long time. The optimized guideline of reclosers on distribution lines is known to improve the reliability of power systems, the protection functions on distribution systems heavily rely on the number and placement of such reclosers. This study reviewed the effect of using protection settings methodology with the number of reclosing operations to reduce the damage sustained during faults on distribution networks. The aim of the study is to determine the number of reclosing operations and fault current conditions based on simulation data of PSCAD/EMTDC for standard distribution networks. It is found that the determination of the number of operations on reclosers, which are the protection function of feeders, helped to optimize the operation and reliability of distribution networks.

Prevention of UV-induced Skin Damage by Activation of Tumor Suppressor Genes p53 and $p14^{ARF}$

  • Petersen, R.;John, S.;Lueder, M.;Borchert, S.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.338-351
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    • 2003
  • UV radiation is the most dangerous stress factor among permanent environmental impacts on human skin. Consequences of UV exposure are aberrant tissue architecture, alterations in skin cells including functional changes. Nowadays new kinds of outdoor leisure-time activities and changing environmental conditions make the question of sun protection more important than ever. It is necessary to recognize that self-confident consumers do not consider to change their way of life, they demand modern solutions on the basis of new scientific developments. In the past one fundamental principle of cosmetics was the use of physical and organic filter systems against damaging UV-rays. Today new research results demonstrate that natural protecting cell mechanisms can be activated. Suitable biological actives strongly support the protection function not from the surface but from the inside of the cell. A soy seed preparation (SSP) was proven to stimulate natural skin protective functions. The major functions are an increased energy level and the prevention of DNA damage. These functions can I be defined as biological UV protection. The tumor suppressor protein p53 plays a key role in the regulation of DNA repair. p53 must be transferred into the phosphorylated form to work as transcription factor for genes which are regulating the cell cycle or organizing DNA repair. A pretreatment with SSP increases the phosphorylation rate of p53 of chronically UV-irradiated human keratinocytes significantly. According to the same test procedure SSP induces a dramatic increase in the expression of the tumor suppressor protein p14$^{ARF}$ that is supporting the p53 activity by blocking the antagonist of p53, the oncoprotein Mdm2. Mdm2, a ubiquitin E3-ligase, downregulates p53 and at the same time it prevents phosphorylation of p53. The positive influence of the tumor suppressor proteins explains the stimulation of DNA repair and prevention of sunburn cell formation by SSP, which was proven in cell culture experiments. In vivo the increased skin tolerance against UV irradiation by SSP could be confirmed too. We have assumed, that an increased repair potential provides full cell functionality.y.

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