• Title/Summary/Keyword: interception

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A Study on Dynamic Triggering mechanism for Lawful Interception via a SIP / IMS Service Mobility detection (SIP/IMS Service Mobility 탐지를 통한 Lawful Interception Dynamic Triggering 기법에 관한 연구)

  • Lee, Myoungrak;Lee, Jung-Been;Han, Youngsub
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.10a
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    • pp.606-609
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    • 2015
  • Lawful Interception (LI)이란 합법적인 형태의 통신내용 및 관련 정보의 수집활동을 말한다. 최근의 4G LTE 기반의 이 기종 통신망에서의 합법적 감청은 전통적인 유선 및 3G 네트워크 중심의 감청기법 이외의 새로운 기법과 표준이 필요한 실정이다. 특히, LTE와 같이 User Equipment (UE)가 네트워크상에서 핸드오버를 통해 자유롭게 이동하거나, 3G와 같은 이 기종 망에서의 연결을 포함한 다른 사업자의 새로운 지역에서의 네트워크 연결이 보장되는 형태의 환경에서의 연속적 감청을 보장하는 것은 합법적 감청분야의 중요한 이슈중의 하나이다. 따라서, 본 논문에서는 국내의 4G-LTE망을 중심으로 기존의 3G 망을 자유롭게 이동하는 네트워크 도메인과 IMS/SIP 기반의 서버의 연속성을 보장하는 서비스 도메인 영역에서의 합법적 감청 기법을 제안한다. 본 논문에서 제안하는 기법은 이 기종 무선망과 유선망이 혼재된 네트워크에서의 IMS/SIP 기반 서비스의 이동성을 감지하여 합법적 감청의 연속성을 보장하기 위한 기법을 포함하고 있다.

Estimating Rainfall Interception Loss of Decomposed Floor in a Deciduous Forest Using Rainfall Simulation Experiments (인공강우실험에 의한 활엽수 부후낙엽층의 강우차단손실량 추정)

  • Ahn, Byungkyu;Choi, Hyungtae;Lee, Qiwen;Im, Sangjun
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.3
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    • pp.181-187
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    • 2014
  • Forest floor is one of most distinctive features of forest ecosystem, which provides plants and soil microbes with nutrients, and controls hydrologic condition within the floor by intercepting water during a rainfall event and evaporates back into the atmosphere. In this study rainfall interception loss by decomposed forest floor of a deciduous forest has been experimentally estimated using rainfall simulation experiments. Litter-decomposing fungi were incubated on deciduous forest floor samples for the experiment purposes. On a deciduous floor, a $4.22mm{\cdot}kg^{-1}{\cdot}m^2$ of rain was intercepted immediately before rain ceased. Minimum values of interception loss ranged from 1.62 to $2.41mm{\cdot}kg^{-1}{\cdot}m^2$, with an average of $1.87mm{\cdot}kg^{-1}{\cdot}m^2$. Mann-Whitney test showed that decomposing fungi on the forest floor influenced on rainfall interception capacity.

A study of the Effect of groin on the Water Quality in the Urban River (방사보가 도시하천수질에 미치는 영향에 관한 연구)

  • Cho, Hong-je;Kim, ill-gwon
    • Journal of Korean Society of Water and Wastewater
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    • v.12 no.3
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    • pp.81-90
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    • 1998
  • The purpose of this study was to analyze the effect of the groin which was constructed in the down stream of urban river for the prevention of sedimentation on the improvement of the water quality. We studied on the groin in the downstream of Taehwa River constructed to keep the navigation depth of Ulsan day, and used the measured data of the water quality and river discharge. In order to analyze the charge of the water quality due to the groin Que12E model was applied, and BOD and DO was examined. The analysis showed that removal of the groin would not have significant effect on the improvement of the water quality, rather, interception of the pollution source coming into the upstream of the groin would be more influential on the improvement of the water quality. Therefore, It was concluded that to improve the water quality in mild bottom slop of tidal river, interception of the pollution source and river maintenance discharge should precede.

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3-D Optimal Evasion of Air-to-Surface Missiles against Proportionally Navigated Defense Missiles

  • Cho, Sung-Bong;Ryoo, Chang-Kyung;Tahk, Min-Jea
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.514-518
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    • 2003
  • In this paper, we investigate three dimensional optimal evasive maneuver patterns for air-to-surface attack missiles against proportionally navigated anti-air defense missiles. Interception error of the defense missile can be generated by evasive maneuver of the attack missile during the time of flight for which the defense missile intercepts the attack missile. Time varying weighted sum of the inverse of these interception errors forms a performance index to be minimized. Direct parameter optimization technique using CFSQP is adopted to get the attack missile's optimal evasive maneuver patterns according to parameter changes of both the attack missile and the defense missile such as maneuver limit and time constant of autopilot approximated by the 1st order lag system. The overall shape of resultant optimal evasive maneuver to enhance the survivability of air-to-surface missiles against proportionally navigated anti-air missiles is a kind of deformed barrel roll.

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Delivering Warrants Model using Blockchain for Seamless Lawful Interception (블록체인 상의 영장 전달을 통한 연속적인 합법적 감청)

  • Lee, Jung-Been;In, Hoh Peter
    • Proceedings of the Korea Information Processing Society Conference
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    • 2017.04a
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    • pp.196-197
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    • 2017
  • 합법적 감청(LI: Lawful Interception)이란, 합법적으로 음성 통신 내용 및 데이터와 그와 관련된 일련의 정보를 수집하는 활동을 말한다. 그러나 IP 기반의 4G-LTE 네트워크와 다수의 사업자망을 이동하는 과정에서 발생되는 반복적인 법원의 영장 재발부 절차는 합법적 감청의 연속성을 저해하는 요소가 되어왔다. 이러한 문제점을 해결하기 위해 재발부 과정을 생략하고, 기존 영장 그대로 다음 국가나 네트워크 사업자에게 전달하는 방식이 제안되었지만, 보안성에 대한 문제가 여전히 존재한다. 본 연구에서는 블록체인 기반의 분산 데이터베이스 상에서 디지털 영장을 발부함으로써 영장의 재발부 과정을 거치지 않으면서도 보안성이 높고 안전하게 연속적인 합법적 감청을 수행할 수 있는 모델을 제안한다.

Performance Comparison of 3-D Optimal Evasion against PN Guided Defense Missiles Using SQP and CEALM Optimization Methods (SQP와 CEALM 최적화 기법에 의한 대공 방어 유도탄에 대한 3차원 최적 회피 성능 비교)

  • Cho, Sung-Bong;Ryoo, Chang-Kyung;Tahk, Min-Jea
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.3
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    • pp.272-281
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    • 2009
  • In this paper, three-dimensional optimal evasive maneuver patterns for air-to-surface attack missiles against proportionally navigated anti-air defense missiles were investigated. An interception error of the defense missile is produced by an evasive maneuver of the attack missile. It is assumed that the defense missiles are continuously launched during the flight of attack missile. The performance index to be minimized is then defined as the negative square integral of the interception errors. The direct parameter optimization technique based on SQP and a co-evolution method based on the augmented Lagrangian formulation are adopted to get the attack missile's optimal evasive maneuver patterns. The overall shape of the resultant optimal evasive maneuver is represented as a deformed barrel-roll.

Auto Alarm System of Replacement Period for Vehicle Cabin Filter & Interception System of High Concentration Dust (차량용 에어컨필터 교환시점 알림 시스템 및 과농도 먼지 차단 시스템)

  • Lee, Kyu-Se;Byeon, Seong-Uk;Kim, Yeong-Min;Park, Sung-Woo;Yum, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.11
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    • pp.1035-1040
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    • 2008
  • Replacement period for vehicle cabin filter of most automobiles is fixed without consideration of conditions of filter and environment. Auto alarm system of replacement period at vehicle cabin filter and interception system of high concentration dust were developed. Control program which is related with the AQS has been developed based on the circuit drive algorithm. This system is expected to be beneficial to passenger's health and to extend the life of the filter which regulates vehicle HVAC system by ventilation mode change at the time of high concentration dust.