• Title/Summary/Keyword: interception

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Throughfall, Stemflow and Rainfall Interception Loss in Pinus koraiensis Sieb. et Zucc., Larix Leptolepis (Sieb. et Zucc.) Gordon and Quercus Species Stand at Kwangju-Gun, Kyunggi-Do (경기도(京畿道) 광주(廣州) 지방(地方) 잣나무림, 낙엽송림 및 참나무림에서 수관통과우(樹冠通過雨), 수간류(樹幹流) 및 차단손실(遮斷損失))

  • Lee, Don Koo;Kim, Gab Tae;Joo, Kwang Yeong;Kim, Young Soo
    • Journal of Korean Society of Forest Science
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    • v.86 no.2
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    • pp.200-207
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    • 1997
  • The throughfall, stemflow and precipitation interception during the period of May to November 1995 were compared between three stands of Pinus koraiensis, Larix leptolepis and Quercus species stand growing at Kwangju-Gun, Kyunggi-Do. The total amount of precipitation during the period in the study area was 1,821mm, higher than average precipitation. The amount of interception showed 21.8% of the total precipitation in Quercus stand, whereas 15.7 and 19.4 in P. koraiensis and L. leptolepis stands, respectively. Precipitation leached on forest floor was occupied mainly by throughfall for all the stands, and it was specially higher in P. koraiensis stand. The amount of stemflow was appeared higher in Quercus stand(5.0%) than P. koraiensis stand(1.1%) or L. leptolepis stand(1.1%). The relationship between throughfall or stemflow and total precipitation in all the stands were highly significant.

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Seamless Lawful Interception Handover for 3G IP Multimedia Subsystem (IMS)

  • In, Hoh Peter;Lee, Myoung-Rak;Kim, Do-Hoon;Kim, Nung-Hoe;Yoon, Byung-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.7
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    • pp.1329-1345
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    • 2011
  • After the 9.11 terror attack, lawful Interception (LI) has emerged as an important tool for anti-terrorist activity. Law enforcement agents and administrative government bodies effectively monitor suspicious target users of permanent IP-based network devices by LI in Packet Data Networks (PDNs). However, it is difficult to perform LI in monitoring migrating users from a location to another, who change their IPs due to the proliferation of portable Internet devices enabling 3G IP Multimedia Subsystems (IMS). The existing, manual handover technique in 3G IMS makes it even more difficult to continue the LI activities due to time-lag reissuance of LI authority warrants when the target users move to a new LI jurisdiction via a roaming service. Our proposed model is a seamless LI handover mechanism in 3G IMS to support mobility detection of the target users. The LI warrants are transferred to the new LI agent automatically with the target users when they move to a new LI jurisdiction. Thus, time-lag human intervention of reissuance of the LI warrants is removed and enables the LI authorities to continue monitoring. In the simulation of our proposed mechanism, the quality of lawful interception achieves a mean score of over 97.5% out of the possible 100% maximum score, whereas the quality of the existing mechanism has a mean score of 22.725%.

A Study of Security for a Spam Attack of VoIP Vulnerability (VoIP 취약점에 대한 스팸 공격과 보안에 관한 연구)

  • Lee, In-Hee;Park, Dea-Woo
    • KSCI Review
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    • v.14 no.2
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    • pp.215-224
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    • 2006
  • Regarding a spam attack and the interception that a spinoff is largest among Vulnerability of VoIP at these papers study. Write scenario of a spam attack regarding VoIP Vulnerability, and execute Call spam. Instant Messaging spam, Presence spam attack. A spam attack is succeeded in laboratories, and prove. and confirm damage fact of a user in proposals of a spam interception way of VoIP service, 1) INVITE Request Flood Attack 2) Black/White list, 3) Traceback, 4) Black Hole-Sink Hole, 5) Content Filtering, 6) Consent based Communication, 7) Call act pattern investigation, 8) Reputation System Propose, and prove. Test each interception plan proposed in VoIP networks, and confirm security level of a spam interception. Information protection of VoIP service is enlarged at WiBro, BcN. and to realize Ubiquitous Security through result of research of this paper contribute, and may make.

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The Dyeing Properties and The Functionality of Fabrics Dyed with Chelidonium Majus Extract (백굴채 추출물을 이용한 염색직물의 염색성 및 기능성)

  • Park, Young-Hee
    • Fashion & Textile Research Journal
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    • v.10 no.2
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    • pp.242-248
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    • 2008
  • This study was aimed to find whether the Chelidonium majus which grows naturally in Korean soil and has a various medical ingredient is valuable as a natural dyeing material and to examine the functionality of Chelidonium majus extract. As the test result of dyeing colorfastness, colorfastness to sunlight was 1st grade for all the dyed fabrics. The colorfastness to laundry for discoloration showed from 1st to 4th grade and that for discoloration showed from 4th to 5th grade through all the dyed fabrics. Colorfastness to perspiration, rubbing, and drycleaning showed from 4th to 5th grade through all the dyed fabrics. In the result of antibiosis test, the dyed cotton fabric showed the bacteria reduction rate of 99.0% for Staphylococcus aureus and Escherichia coli evenly when washed one, three, and five times, The dyed silk fabric, when washed one, three, and five times, showed the bacteria reduction rate of 99.0% for Staphylococcus aureus, but didn't showed the significant bacteria reduction. As the test result of sun protection test, in the case of the cotton fabric which was dyed but don't use mordant, after one-time washing, S.P.F.(Sun Protection Factor) showed 20.4, the interception rate of UV-A showed 94.3%, and that of UV-B showed 95.2%. After five-time washing, S.P.F. showed 14.3, the interception rate of UV-A showed 90.0%, and that of UV-B showed 93.2%. In the case of the silk fabric which was dyed but don't use mordant, after one time washing, S.P.F. showed 30.5, the interception rate of UV-A showed 95.9%, and that of UV-B showed 96.9%, after five-time washing, S.P.F. showed 31.0, the interception rate of UV-A showed 95.6%, and that of UV-B showed 96.7%.

Turbo Equalization for Covert communication in Underwater Channel (터보등화를 이용한 직접대역확산통신 기반의 은밀 수중통신 성능분석)

  • Ahn, Tae-Seok;Jung, Ji-Won;Park, Tae-Doo;Lee, Dong-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.8
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    • pp.1422-1430
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    • 2016
  • Researches for oceans are limited to military purpose such as underwater sound detection and tracking system. Underwater acoustic communications with low-probability-of-interception (LPI) covert characteristics were received much attention recently. Covert communications are conducted at a low received signal-to-noise ratio to prevent interception or detection by an eavesdropper. This paper proposed optimal covert communication model based on direct sequence spread spectrum for underwater environments. Spread spectrum signals may be used for data transmission on underwater acoustic channels to achieve reliable transmission by suppressing the detrimental effect of interference and self-interference due to jamming and multipath propagation. The characteristics of the underwater acoustic channel present special problems in the design of covert communication systems. To improve performance and probability of interception, we applied BCJR(Bahl, Cocke, Jelinek, Raviv) decoding method and the direct sequence spread spectrum technology in low SNR. Also, we compared the performance between conventional model and proposed model based on turbo equalization by simulation and lake experiment.

A Design of Encryption Method for Strong Security about Tapping/Interception of VoIP Media Information between Different Private Networks (이종 사설망간에 VoIP 미디어의 도.감청 보안 강화를 위한 암호화 기법 설계)

  • Oh, Hyung-Jun;Won, Yoo-Hun
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.3
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    • pp.113-120
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    • 2012
  • VoIP provides voice data service using existing IP networks and has received much attention recently. VoIP service has a variety of security vulnerabilities. Types of main attacks on VoIP service are tapping/interception, DoS attacks, spam, misuse of service attacks and the like. Of these, confidential information leak because of tapping/interception has been considered as a critical problem. Encryption techniques, such as SRTP and ZRTP, are mostly used to prevent tap and intercept on VoIP media information. In general, VoIP service has two service scenarios. First, VoIP service operates within a single private network. Second, VoIP service operates between different private networks. Both SRTP and ZRTP for VoIP media information within a single private network can perform encryption. But they can not perform encryption between different private networks. In order to solve this problem, in this paper, we modify SRTP protocol. And then, we propose an encryption method that can perform encryption of VoIP media information between the different private networks.

Relation of Run- off and Canopy Interception to Rainfall in a Mixed Forest (혼효림(混淆林)에서 강우량(降雨量)이 유출량(流出量) 및 수관차단률(樹冠遮斷率)에 미치는 영향)

  • Lee, Sang Hwan
    • Journal of Korean Society of Forest Science
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    • v.35 no.1
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    • pp.36-38
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    • 1977
  • Some characteristics of rainfall interception and surface runoff from total rainfall at a forest stand mixed with Pinus densiflora and Alnus hirsuta in 1975 was analysised and the results obtained are as fellow; 1. The annual interception of rainfall by the forest canopy was 19.3 percent to annual rainfall 1,072.7mm. 2. The rate of rainfall interception in the dry season as spring and early summer was of 20 to 50 percent and less than 15 percent in the rainy season as summer. 3. About 50 percent of rainfall was intercepted in case of less than 10mm of every rainfall by the forest canopy and, in more than 20mm, about 20 percent intercepted.

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Physico-Chemical Properties of Rainfall Interception Culture and Open Field Culture Soils of Rubus sp. In Gochang-gun, Jeollabuk-do (고창지역 복분자 비가림하우스 토양과 노지토양의 물리·화학적 특성)

  • Chung, Byung-Yeoup;Lee, Kang-Soo;Kim, Myung-Kon;Choi, Young-Hee;Kim, Moo-Key;Cho, Jae-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.5
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    • pp.303-309
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    • 2008
  • The physico-chemical properties of the rainfall interception culture (85 sites) and the open field culture soils (85 sites) in the area of Gochang-gun, Jeollabuk-do were surveyed. Soil textural distribution of the rainfall interception culture and the open field culture soils was 74% and 64% for silt loam, 16% and 35% for loam, and 10% and 1% for clay, respectively. The percentage of aggregate rates was higher in the open field culture soils (60.06%) than rainfall interception culture soils (55.84%). Electrical conductivity, exchangeable cations, and anions in the rainfall interception culture soils were higher than those in open field soils. Specially, accumulated amount of anion in rainfall interception culture soils was remarkably higher 2~3 times than open field culture soils. The results from the analyses of rainfall interception culture soils suggested that the most critical problem is the salts accumulation caused by over-fertilization of chemical fertilizer and compost. Therefore, application rates of chemical fertilizer and compost should be controlled in order to conservation of soil and water for sustainable agriculture.

The Design Method of Transverse Grate Inlets on Steep Local Road (급경사 국지도로에서의 횡유입부 설계 방법)

  • Kim, Jea-Kwon;Kim, Jung-Soo;Lee, Joon-Ho;Yoon, Sei-Eui
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.195-198
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    • 2007
  • The type, the length, and the install space of the grate inlets in main street were designed with the consideration of discharge calculated with street surface rainfall. However, the discharge that was not intercepted at transverse grate inlets in steep local roads increases inundation areas around main street Therefore, it is necessary to analyze the flow characteristics and interception capacity at transverse grate inlets in steep local roads. Hydraulic experimental apparatus which can be changed the longitudinal slopes($2{\sim}10%$) of street, the size ($20{\sim}50cm$) and the types(TYPE I, II) of grate inlet was installed for this study. The range of the experimental discharges were from $2{\ell}/sec$ to $24{\ell}/sec$. The interception discharges of transverse grate inlets per unit width changing the longitudinal slope of steep local road were calculated by the hydraulic experimental results. The design method of transverse grate inlets was developed by the interception discharges per unit width. This design method was applied to decide the space and size of transverse grate inlets.

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A Seamless Lawful Interception Architecture for Mobile Users in IEEE 802.16e Networks

  • Lee, Myoung-Rak;Lee, Taek;Yoon, Byung-Sik;Kim, Hyo-Gon;In, Hoh Peter
    • Journal of Communications and Networks
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    • v.11 no.6
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    • pp.626-633
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    • 2009
  • Lawful interception (LI) involves legally accessing private communication such as telephone calls or email messages. Numerous countries have been drafting and enacting laws concerning the LI procedures. With the proliferation of portable Internet services such as the IEEE 802.16e wireless mobile networks, surveillance over illegal users is an emerging technical issue in LI. The evermigrating users and their changing IP's make it harder to provide support for seamless LI procedures on 802.16e networks. Few studies, however, on seamless LI support have been conducted on the 802.16e mobile networks environments. Proposed in this paper are a seamless LI architecture and algorithms for the 802.16e networks. The simulation results demonstrate that the proposed architecture improves recall rates in intercepting mobile user, when compared to the existing LI architectures.