• 제목/요약/키워드: stream side

검색결과 294건 처리시간 0.028초

스트림 암호 Rabbit에 대한 전력분석 공격 (Power Analysis Attacks on the Stream Cipher Rabbit)

  • 배기석;안만기;박제훈;이훈재;문상재
    • 정보보호학회논문지
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    • 제21권3호
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    • pp.27-35
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    • 2011
  • 무선 센서 네트워크(wireless sensor network)의 센서 노드는 특성상 전력 소모량, 전송 속도 및 도달 거리 등이 고려되어 설계되야 하며, 여러 형태의 공격(도청, 해킹, 가입자 비밀정보 유출, 서비스 도착상태 등)에 안전해야 한다. 최근 유럽연합의 eSTREAM 공모사업에서 소프트웨어 분야에 선정된 Rabbit 알고리듬은 ISO/IEC 18033-4 기술분야에 추가 선정되었으며 무선 센서 네트워크에 적용 가능한 스트림 암호이다. 이러한 Rabbit 알고리듬은 이론적 분석에 의해 부채널분석 공격에 대한 복잡도가 중간수준(medium)으로 평가됨에 따라, 본 논문에서는 Rabbit에 대한 전력분석 공격방법을 제안하고 실험을 통하여 검증하였다. 실험을 위해서 프로그래밍이 가능한 고성능 8비트 RISC 계열의 AVR 마이크로프로세서 (ATmega128 L)를 장착한 IEEE 802.15.4/ZigBee 보드에 전력분석 공격의 대응방법이 적용되지 않은 시스템을 구현하고, 해밍무게 모델을 적용한 전력분석 공격을 실시하였다.

상호 작용 계수를 이용한 측추력 제트와 초음속 자유류 상호 작용에 관한 연구 (Analysis of the Interaction Between Side Jet and Supersonic Free Stream Using K-factor)

  • 김민규;이광섭
    • 한국군사과학기술학회지
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    • 제15권1호
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    • pp.101-110
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    • 2012
  • The side jet effects between jet flow and free-stream on a missile body were investigated by experimentally and numerically for modeling aerodynamic coefficients in pitch plane. K-factors for normal force and pitching moment were introduced to estimate the side jet effects. The main parameters of the jet interaction phenomena were angle of attack, jet pressure ratio, Mach number and jet bank angle. The K-factors for normal force coefficient and pitching moment coefficients in pitch plane were analysed.

일본(日本)에서 계류변(溪流邊)의 환경복원(環境復元) 발전전략(發展戰略) II - 임도(林道) 및 치산(治山)·사방(砂防)을 중심(中心)으로 - (Strategy Prospects of Environmental Restoration of Stream Side in Japan - With a Special Reference to the Forest Road, Forest Conservation and Erosion Control -)

  • 박재현;우보명;권태호;이헌호
    • 한국환경복원기술학회지
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    • 제3권2호
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    • pp.66-74
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    • 2000
  • This study was carried out to introduce current status and development strategy for an environmental restoration of stream side in Japan, and to consider a methodology which could be effectively applied for the environmental restoration of stream side in Korea. The strategy prospects of environmental restoration in Japan were summarized as follows: 1. We should establish a new paradigm of forest road, forest conservation and erosion control which can emphasize the restoration of the streamside ecosystem and reduce the effects of soil movement change in the areas. And we should maintain the biotic habitats to conserve native biotic community when we practice forest road, forest conservation and erosion control works. 2. In the point of view ecological conservation aspects, we should evaluate the effects of new forest conservation and erosion control methods which is emphasized on the restoration of the streamside ecosystem to apply desirable methodology to the environmental restoration of the streamside area. 3. In the past, the objective of forest conservation and erosion control was to fix a soil by construction of permanent structures. Whereas, the direction of future's forest conservation and erosion control needs to change new forest conservation and erosion control technology to prevent large scale soil movement but allow small scale soil movement to conserve sound ecosystem and biotic habitats. 4. The restoration of the streamside ecosystem should provide continuity of the streamside environment which allows desirable biological habitats, and environmentally sound facilities to harmonize the environment.

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설악산 상천 계곡의 황철나무 (On the Populus maximowiczii Forest of Sangcheon Ravine, Mt. Seolag)

  • Yim, Yang-Jai
    • Journal of Plant Biology
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    • 제27권2호
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    • pp.95-103
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    • 1984
  • The Populus maximowiczii dominated forest of the Sangcheon ravine, Mt. Seolag, is distributed in the area with the conglemerates substrate, along the ravine stream from 170m to 550m in altitude. Toward the both slopes of the northern and southern peak from the stream side, the zonal distribution of vegetation was recognized; P. maximowiczii forest of Pinus densiflora forest and deciduous broad leaved forest. The pure community of P. maximowiczii with even more 80-98% in relative basal area (aspen basal area/basal area) was found in the ravine area from 360m to 420m in altitude, the optimal ranges in the species and community by two dimensional ordination with thermal and xeric cline axis. The species compete with Pinus densiflora, in the ravine stream side, and with deciduous broad leaved tree species such as Fraxinus rhynchophylla, Prunus sargentii, Lindera obtusiloba, in the mountain slope sides. On the other hand, the ravine vegetation, including the aspen forest, was classified into Pinus densiflora, Pinus densiflora-Carpinus laxiflora, Pinus densiflora-Populus maximowiczii, jessoensis, Acer mono-Fraxinus rhynchophylla, Carpinus laxiflora-Quercus mongolica, Quercus variabilis-Quercus ariena, Quercus ariena, Quercus variabilis-Stephanandra incisa, Picrasma quassioides-Celtis sinensis, Betula davurica-Zanthoxylum schinifolium and Styrax obassia-Lindera obtusiloba association.

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Supplementation of French Maritime Pine Bark Extract (Pycnogenol®) Prevents Lung Injury and Lipid Peroxidation in Nude Mice Exposed to Side-Stream Cigarette Smoke (SSCS)

  • Lee, Jeong-Min;Hwang, Kwon-Taek;Lee, Jong-Moon;Kim, Sun-Ho;Watson, Ronald R.;Park, Kun-Young
    • Preventive Nutrition and Food Science
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    • 제9권1호
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    • pp.65-70
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    • 2004
  • Side-stream cigarette smoke (SSCS) is a major component of environmental tobacco smoke. The purpose of this study was to investigate the development of lung injury and lipid peroxidation in the lung and liver of immunodeficient (Nude) mice exposed to acute SSCS (a total 5 hours of exposure). The effects of French maritime bark extract (Pycnogeno $l^{ⓡ}$) supplementation of the mice were also determined. SSCS increased pulmonary resistance and lipid peroxidation in these mice. Pycnogeno $l^{ⓡ}$ supplementation increased vitamin E levels in lung and liver. In addition, Pycnogeno $l^{ⓡ}$ attenuated SSCS-mediated lung injury and lipid peroxidation. It appears that the enhanced resistance against SSCS-induced lung injury and lipid peroxidation may be primarily due to the antioxidant property of Pycnogeno $l^{ⓡ}$ in supplemented mice.

낙동강 유역에 대한 일별 유달부하량 산정모델개발 II. 모델식의 활용 (Development of the Estimation Model on Daily Pollutant Loads for the Nakdong River Basin II. Application of the Model)

  • 윤영삼;유재정;김문수;이혜진;이준배;양상용
    • 한국환경과학회지
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    • 제16권3호
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    • pp.333-345
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    • 2007
  • As analyzed the estimated values of the daily delivery loads from thirteen major side streams such as Naesung-river, Keumho-river, Hwang-river, Nam-river during five years (from 1999 to 2003), the daily BOD inflow into the main stream of Nakdong river in 2003 shows the highest quantity as 31.1 ton and the daily BOD inflows in 1999, 2000, 2001, and 2002 are 26.7 ton, 22.5 ton, 21.0 ton, 25.8 ton, respectively. The daily TN in-flow into the main stream of Nakdong river in 2003 shows also the highest quantity as 64.9 ton and the daily TN inflows in 1999, 2000, 2001, and 2002 are 55.19 ton, 46.27 ton, 39.5 ton, 53.38 ton, respectively. The daily TP inflow into the main stream of Nakdong river in 2003 shows the highest quantity as 2.70 ton likewise and the daily TP inflows in 1999, 2000, 2001, and 2002 are 2.17 ton, 1.87 ton, 1.60 ton, 2.10 ton, respectively The rate of BOD loads from each side main stream into the main stream of Nakdong river shows that the BOD loads of Keumho-river are the highest as the values range from 32.8 % (2002) ${\sim}$ 35.1 % (2003) and the BOD loads of Nam-river, Naesung-river, Hwang-river are high in the order named. The rate of TN loads to the main stream is also similar to the trend of BOD loads. The contribution of the TN loads of Geumho-river to the contamination of the main stream is also the highest having a range from 27.0 % (2002) to 28.8 % (1999) among the main side streams and the TN loads of Naesung-river, Nam-river, and Heachun-river are high in the order named. The rate of TP loads is quite different from the trend of BOD and TN loads. The TP rate of Keumho-river, however, is still the highest as ranging 58.6 % (2002) to 61.7 % (2003) and the river has the biggest portion (over 50%) of the entire pollution to the main stream of Nakdong river.

흡연 궐련중의 니코틴이행에 관하여 (On the Mass Transfer of Nicotine in Smoking Cigarette)

  • 김찬호;유점호;반유선;류익상
    • 한국연초학회지
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    • 제3권2호
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    • pp.83-88
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    • 1981
  • Transfer of nicotine into the mails stream of smote in Korean commercial cigarettes was investigated. The mass transfer of nicotine into tile main stream of smote and accumulation of nicotine in cigarette filler got higher as the puffing number increased. Only about 14oyo of nicotine ill a cigarette was puffed into mouth end. and the rest of the nicotine went to side stream of smote or converted to other volatile bases.

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동결융해침식 토사가 계류수의 수질에 미치는 영향 - 북한산국립공원 북동사면 일대를 중심으로 - (Influences of the Solifluction Soil on the Physicochemistry of Stream Water Quality -With a Special Reference on Northeastern Side Slopes Area of Bughansan National Park-)

  • 박재현
    • 생태와환경
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    • 제36권2호통권103호
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    • pp.200-207
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    • 2003
  • 본 연구는 북한산국립공원 북동사면 일대에서 계류수질에 미치는 동결융해침식토사의 영향을 파악함으로써 국립공원내 계류수질 보전을 위한 과학적 기초 자료를 제공하기 위하여 2002년 3월부터 5월까지 수행하였다. 조사기간 동안 계류수의 평균 pH는 동결융해침식토사의 평균 pH보다 높았으며, 계류수의 평균 전기전도도는 상류유역이 하류유역보다 약 2.1${\sim}$2.8배 낮은 값을 나타내었다. 또한, 직선회귀분석결과 동결융해침식된 토사와 계류수에서의 pH와 음이온량 ($Cl^-,\;N0_3\;^-, So_4\;^{2-}$)은 정의 상관관계를 나타내었다.

가압식 분리막을 이용한 Side-Stream MBR 공정의 비정상 운전조건에서 막 오염 저감 (Fouling Mitigation for Pressurized Membrane of Side-Stream MBR Process at Abnormal Operation Condition)

  • 고병곤;나지훈;남덕현;강기훈;이채영
    • 대한환경공학회지
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    • 제38권6호
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    • pp.323-328
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    • 2016
  • 공기주입형 가압식 MBR 공정은 일반적인 침지식 MBR 공정과 마찬가지로 정상 운전조건에서 막 오염에 대한 제어 및 관리 기술뿐만 아니라 저유량, 저부하 조건과 같은 비정상 운전조건에서도 시설의 운영에 지장이 없도록 막 오염에 대한 제어 대책이 필요하다. $85m^3$/일 규모의 공기주입형 가압식 MBR 실증시설 운영을 통해 공기주입에 의한 분리막 오염 저감효과와 비상 시 운전조건에서 미생물에 의해 나타날 수 있는 막 오염 문제를 고찰하였다. 가압식 분리막에서 공기의 주입은 분리막 표면에서 공기방울에 의한 scouring 효과에 의해 TMP 상승 기간을 연장시키고 처리의 안정성과 높은 효율의 플럭스($40L/m^2{\cdot}h$ 이상)를 장시간 유지할 수 있는 것으로 분석되었다. 비정상 운전조건에서는 생물반응조에 PACl (53 mg/L as Al)을 주입한 경우 19%의 TMP 상승 감소효과가 있었으나 MBR 공정의 비정상 운전조건 지속에 따른 반복적인 PACl의 주입은 질산화 미생물의 활성도에 영향을 미치게 되어 궁극적으로 질소 처리효율이 악화될 수 있음을 회분식 배양 실험을 통해 확인하였다. 생물반응조에 PAC (0.6 g/L)을 주입한 경우에서는 연속운전 5일 동안 TMP 상승 없이 운전 초기 TMP인 $0.2kg/cm^2$을 유지하여 안정적으로 운전이 가능하였다. 이것은 미생물의 성장 저해조건에서 막 오염 원인물질을 유발하는 EPS와 같은 고분자 물질의 흡착에 따른 것으로 판단된다.

하천 조성 기법에 따른 서호천 식생 및 식물상의 차이 비교 (The Differentiation on the Plant Flora and Vegetation Caused by the Different Technique of Stream Restoration at the Seo-Ho Stream)

  • 김송이;김혜주;이규석
    • 한국환경복원기술학회지
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    • 제7권3호
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    • pp.26-34
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    • 2004
  • It is expected that the different techniques of stream restoration could be caused the different conditions of the stream ecosystem. The study was to investigate and compare plants and vegetation clusters of appearing plant species in the upper and lower section of the Seo-Ho stream, It was classified and listed all of the plants appeared in the upper and lower section of the stream, It was used the belt-transect method and Unweighted pair group method using arithmetic algorithm in order to examine and analyzed discover the vegetation clusters, In the result, 28 families and 114 species appeared in the upper section, In the other side, 26 families and 93 species appeared in the lower section of the steam. The naturalized index of the upper section was 21%, and that of the lower section was 27%. In addition, the upper section has more various geographical features than lower section of the stream. So that, consequently the study shows that the different techniques of stream restoration could be caused the different growth of the stream ecosystem.