• 제목/요약/키워드: level of protection

검색결과 2,236건 처리시간 0.029초

저압용 서지 보호 장치(SPD)의 보호 거리 해석 (Analysis of the Protective Distance of Low-Voltage Surge Protective Device(SPD) to Equipment)

  • 이정우;오용택
    • 조명전기설비학회논문지
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    • 제26권4호
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    • pp.28-34
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    • 2012
  • Installing surge protection devices for a low-voltage system is important to ensure the survival of electric or electronic devices and systems. If surge protection devices (SPD) are installed without consideration of the concept of lightning protection zones, the equipment to be protected might be damaged despite the correct energy coordination of SPDs. This damage is induced by the reflection phenomena on the cable connecting an external SPD and the load protected. These reflection phenomena depend on the characteristics of the output of the external SPD, the input of the loads, and the cables between the load and the external SPD. Therefore, the SPD has an effective protection distance under the condition of the specific load and the specific voltage protection level of SPD. In this paper, PSCAD/EMTDC software is used to simulate the residual voltage characteristics of SPD Entering the low-voltage device. And by applying a certain voltage level, the effective protection distances of SPD were analyzed according to the each load and length of connecting cable, and the effectiveness of SPD were verified.

협조된 SPD시스템에서 접속선의 길이가 에너지협조에 미치는 영향 (Influences of the Length of Connecting Leads on the Energy Coordination in Coordinated SPD Systems)

  • 이복희;신희경
    • 조명전기설비학회논문지
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    • 제28권6호
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    • pp.91-98
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    • 2014
  • For the purpose of designing and applying the optimum surge protection scheme, multi-stage coordinated surge protective device(SPD) system is suitable to successfully fulfill its tasks; first, to divert a large amount of the transient energy, second, to clamp the overvoltage to the level below the withstand impulse voltage of the equipment to be protected. The length of SPD connecting leads shall be as short as possible. Long connecting leads will degrade the protection effect of SPDs. In this paper, the influences of the length of connecting leads on the energy sharing in a coordinated SPD system were investigated experimentally, and the simulation of determining the energy sharing and protection voltage level of each SPD depending on the length of connecting leads was carried out by using P-spice program. It was confirmed that the protection voltage level and energy sharing in coordinated SPD systems are strongly influenced by the length of connecting leads.

WDM Mesh 네트워크에서 SLA 복구시간을 만족시키는 보호기법 (Protection Scheme Guaranteeing the Recovery Time Defined in Service Level Agreement in WDM Mesh Networks)

  • 홍기원;임태형;경연웅;박진우
    • 한국통신학회논문지
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    • 제39B권1호
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    • pp.41-43
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    • 2014
  • WDM 광 전달망에서 기존의 보호방식은 SLA에 명시된 복구 시간에 대한 고려 없이 모든 연결 요청에 대해 한 쌍의 경로를 설정함으로써, 네트워크 자원의 이용 효율이 감소하고 SLA 위반율이 높아진다. 이를 해결하기 위해 본 논문에서는 예상 보호시간과 SLA에 명시된 복구시간을 비교하여 연결요청을 분류하고, 각 연결 요청 분류에 따른 최적의 망 보호방식 및 백업경로를 설정하는 보호기법을 제안한다. 제안 기법을 실험 망에 적용하여 기존 보호기법보다 높은 자원 효율성 및 낮은 SLA 위반율을 보임을 입증한다.

LVTSCR 구조를 이용한 향상된 전류구동 특성을 갖는 자동차용 ESD 보호회로 연구 (A study of Automotive ESD Protection Circuit with improved Current Driving characteristics Using LVTSCR Structure)

  • 송보배;김영철
    • 전기전자학회논문지
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    • 제28권2호
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    • pp.204-208
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    • 2024
  • 본 논문에서는 ESD 보호회로의 전류구동 특성을 향상시키기 위해 일반적인 저전압용 ESD 보호회로인 LVTSCR의 구조적 변경을 적용한 ESD 보호회로를 제안한다. LVTSCR 구조에서의 electric field와 ESD 전류 경로가 형성 되는 영역을 분리하여 전력 소모를 최소화 하였으며 이에 대한 전기적 특성을 분석하고 전류 구동 특성을 개선하였다. 시뮬레이션을 통한 System-level 특성 저하에 기인하는 구조적인 문제를 분석하였으며 이를 반영하여 특성을 검증하였다. 제안된 ESD 보호회로의 전기적 특성은 TCAD 시뮬레이션을 통해 검증하였으며 HBM 모델링 및 System-level 모델링을 통해 분석하였다. 또한, DB-Hitek사의 0.18um BCD 공정을 통해 silicon 제작 및 HBM 10kV 특성 검증하였다.

다단계 바이러스 차단 구조 연구 (Multi-level Protection Infrastructure for Virus Protection)

  • 노시춘;김귀남
    • 한국사이버테러정보전학회:학술대회논문집
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    • 한국사이버테러정보전학회 2004년도 제1회 춘계학술발표대회
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    • pp.187-198
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    • 2004
  • virus방역 체계 관리는 network infra구조관리, traffic소통경로관리. 방역 zone설정, gateway구간 방역관리이다. 본 논문은 일반적인 방역체계 구조의 성격과 취약점을 진단하고 이를 개선할 수 있는 대책으로서 개선된 방역체계를 설계하였다. 또한 설계된 방역체계와 configuration, mechanism하에서는 어느 정도의 개선효과 나타나고 있는지 분석하였다. 개선된 다단계 방역체계 하에서는 gateway 단계에서 불필요한 mail을 걸러주므로서 server에 주는 부하는 감소하며 virus wall상의 CPU부하의 감소와 virus 치료율의 상승으로 송신 적체 건수는 감소하고 시스템 process수는 증대하고있다.

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Guaranteed GNSS-based Road Charging Applications through User-Level Integrity

  • Mark, Audrey;Schortmann, Joaquin Cosmen;Olague, Miguel Angel Martinez;Merino, Miguel Romay
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.77-82
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    • 2006
  • Integrity plays a fundamental role in the feasibility of 'liability critical' applications. Road charging, e.g. road tolling in urban zones or on highways, represents a series of liability critical applications where a guarantee in integrity could be a true enabler: being the mechanism that prevents the incorrect charging of users and enabling the advancement of these applications using GNSS such as Galileo and EGNOS that provide integrity mechanisms. However, the integrity of the end user position is not guaranteed by the EGNOS and Galileo integrity services alone as provided. Algorithms have been developed to supply a guarantee on the performance attainable at the user level through the provision of a horizontal protection level that responds to local user conditions such as multipath or interference. In addition, an application has been developed that implements road charging mechanisms based on the availability of user-level integrity. Results obtained show that the user-level integrity algorithms provided the required level of integrity guarantee and granularity of the horizontal protection levels necessary for executing urban and rural (highway) road charging. In addition, the road charging application developed shows that the current application domain requirements can be met through the provision of guaranteed integrity and that further reductions in the horizontal protection levels along with increased signal availability will enable future road charging modalities.

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2단 종속 SPD시스템의 보호특성 (Protection Characteristics of Two-Stage Cascade SPD Systems)

  • 이복희;신희경
    • 조명전기설비학회논문지
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    • 제27권5호
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    • pp.95-103
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    • 2013
  • Protection of the electrical and electronic equipment against surges in low voltage AC power distribution systems is based on wide applications of surge protective devices(SPDs). Cascade application of SPDs located at the service entrance of a building and near sensitive equipment is intended to ensure the optimal voltage protection level and energy sharing among cascade SPDs. In this paper, when surges impinge at the service entrance of the building of interest, the protection characteristics of two-stage cascade SPD systems were investigated. The influence of the distance between the upstream and downstream SPDs on the voltage protection level and energy sharing of the two-stage cascade SPD systems were analyzed experimentally. It was found that the energy sharing of two-stage cascade SPD systems strongly depends on the distance between the two SPDs and the component of SPD. As the distance between the two SPDs increases, the energy absorbed by the upstream SPD increases while the energy absorbed by the downstream SPD decreases. Consequently, it is desirable to select the upstream and downstream SPDs having the proper energy capability with due consideration of the distance between the two SPDs.

Mobile Payment Use in Light of Privacy Protection and Provider's Market Control

  • Mohammad Bakhsh;Hyein Jeong;Lingyu Zhao;One-Ki Daniel Lee
    • Asia pacific journal of information systems
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    • 제31권3호
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    • pp.257-276
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    • 2021
  • This study investigates the factors that facilitate or hinder people to use mobile payment, especially drawing upon the theoretical perspectives on individual's privacy protection motivation and perceived market condition. Survey data (n = 200) were collected through a web-based platform and used to test a theoretical model. The results show that one's privacy protection power is formed by various individual and technological factors (i.e., perceived data exposure, self-efficacy, and response efficacy), and in turn it determines his/her intention to use mobile payment. Moreover, the relationship between privacy protection power and mobile payment use is conditional on the perceived market control by the service provider - with a perception of the high level of provider's market control, one uses mobile payment regardless of his/her privacy protection power, while under the low level of provider's market control, the decision depends on the degree of privacy protection power. The findings would help our understanding of why some people are more susceptible to mobile payment and others are not.

소비자상담 현장실습에 대한 실습생의 평가 및 실습만족도 (Interns′ Evaluation and Satisfaction with their Consumer Counseling Internship Programs)

  • 허경옥
    • 가정과삶의질연구
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    • 제22권5호
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    • pp.293-302
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    • 2004
  • This study investigated the internship experiences of female college students who have participated in consumer counseling programs. The factors that determine interns' counseling time and interns' level of satisfaction with the programs were examined. Major results of this study are summarized in the following. First, interns' time spent on counseling consumers was the longest for the program at the Korean Consumer Protection Board, followed by the programs at consumer agencies and firms. The time spent on counseling by interns was shorter when there was l) a larger number of employees; 2) a smaller proportion of female employees: 3) a larger number of counseling rooms and a higher the frequency of counseling at the agency; and 4) a lower evaluation on the work performance of the counseling agency and the employees. Second, the level of utilization of interns was the highest in consumer agencies, followed by the Korean Consumer Protection Board. When all employees were female and the evaluated level of work performance of the counseling agency and employees was high, the level of intern utilization was also high. Third, the evaluated level of work performance was the highest at the Korean Consumer Protection Board, and interns' satisfaction with the internship program was the highest with the consumer agencies and the Korean Consumer Protection Board. Fourth, interns were highly satisfied with the program when the level of intern utilization was high and the agency's operation was evaluated as good.

기업의 침해사고 예방을 위한 관리 모델 (A Study on the Effective Countermeasures for Preventing Computer Security Incidents)

  • 강신범;이상진;임종인
    • 정보보호학회논문지
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    • 제22권1호
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    • pp.107-115
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    • 2012
  • 우리나라의 정보화 수준과 비교하여 정보보호 수준은 상대적으로 낮다. 정보보호 예산 수준 역시 전체 정보화 예산대비 5%대로 미미하며 기업들의 사후대응 중심의 정보보호 조치는 반복적인 피해비용을 야기한다. 정보보호 침해사고에 대한 대응은 사후대응 체계에서 예방과 사전탐지 중심으로 바뀌어야한다. 정보사회에서의 침해사고 대응은 개인의 책임보다는 국가와 기업이 공동으로 대처해야할 영역이라는 인식 전환이 필요하다. 2004년 정보보호조치 및 안전진단 관련 지침이 고시되면서 우리나라도 침해사고 예방을 위한 제도적 기반을 마련하였다. 하지만 제도적으로 시행되고 있는 관리적, 기술적, 물리적 보호조치가 실제 침해사고 대응에 완벽한 예방책이 되지는 못한다. 본 연구에서는 현행 제도적 보호조치의 예방 효과에 대해 살펴보고 제도적 한계와 개선점을 도출하여 기업들이 실질적인 목표 보안수준을 유지하기 위해 필요한 효과적인 침해 예방 대응책으로써의 선행위협 관리 모델을 제안한다.