• Title/Summary/Keyword: first attack

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Digital Watermarking on Image for View-point Change and Malicious Attacks (영상의 시점변화와 악의적 공격에 대한 디지털 워터마킹)

  • Kim, Bo-Ra;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of Broadcast Engineering
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    • v.19 no.3
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    • pp.342-354
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    • 2014
  • This paper deals with digital watermarking methods to protect ownership of image with targeting the ultra-high multi-view or free-view image service in which an arbitrary viewpoint image should be rendered at the user side. The main purpose of it is not to propose a superior method to the previous methods but to show how difficult to construct a watermarking scheme to overcome the viewpoint translation attack. Therefore we target the images with various attacks including viewpoint translation. This paper first shows how high the error rate of the extracted watermark data from viewpoint-translated image by basic schemes of the method using 2DDCT(2D discrete cosine transform) and the one using 2DDWT(2D discrete wavelet transform), which are for 2D image. Because the difficulty in watermarking for the viewpoint-translated image comes from the fact that we don't know the translated viewpoint, we propose a scheme to find the translated viewpoint, which uses the image and the corresponding depth information at the original viewpoint. This method is used to construct the two non-blind watermarking methods to be proposed. They are used to show that recovery of the viewpoint affect a great deal of the error rate of the extracted watermark. Also by comparing the performances of the proposed methods and the previous ones, we show that the proposed ones are better in invisibility and robustness, even if they are non-blind.

Security Threats Analysis for Network-based Mobile IPv6 (네트워크 기반 Mobile IPv6 보안 취약점 분석)

  • Kim, Hyun-Gon;Seo, Jae-Hyeon;Oh, Byeong-Kyun;Ahn, Tae-Nam;Kim, Jin-Hyung
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.10
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    • pp.137-147
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    • 2007
  • In the host-based Mobile IPv6, a mobile node is responsible for doing the signaling to its home agent to enable session continuity as it moves between subnets. To remove the mobile node's signalling processing load, the network-based Mobile IPv6 has been proposed recently. It allows session continuity for a mobile node without its involvement in mobility management. The proxy mobility agent in the network performs the signaling and does the mobility management on behalf of the mobile node. However, to make secure communications for a mobile node, security mechanisms against diverse attacks should be adopted. To do this, first of all security threats to the network-based Mobile IPv6 should be also identified and analyzed. Potential attack objectives may be to consume network services at the cost of a legitimate mobile node and, eavesdropping and fabrication of user traffic through interception of a mobile node's communications. This paper identifies and discusses security threats to the network-based Mobile IPv6 in details. The results of threats analysis are limited to threats that are peculiar to the network-based Mobile IPv6 except threats to IPv6 in general.

Isolation and Characterization of Alga-Lytic Bacterium HY0210-AK1 and Its Degradability of Anabaena cylindrica (남조류 분해세균 HY0210-AK1의 분리와 특성 및 Anabaena cylindrica 분해 활성)

  • 장은희;김정동;한명수
    • Korean Journal of Environmental Biology
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    • v.21 no.2
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    • pp.194-202
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    • 2003
  • To isolate alga-lytic bacteria, a number of samples were collected from Lake of Sukchon and Pal'tang reservoir where cyanobacteria blooming occurred. HY0210-AK1, which exhibited high alga-lytic activity, was isolated using Anabaena cylindrica lawn. The morphological and biochemical characteristics of the isolate HY0210-AK1 were very similar to that of the genus Rhizobium. Taxonomic identification including 16S rDNA base sequencing and phylogenetic analysis indicated that the isolate Hy0210-AK1 had a 99.1% homology in its 16S rDNA babe sequence with Sphingobium herbicidovorans. A. cylindrica NIES-19 was susceptible to the alga-lytic bacterial attack. The growth-inhibiting offset of the bacterium was not different on A. cylindrica NIES-19 when Sphingobium herbicidovorans HY0210-AK1 was in the lag, exponential, and stationary growth phase, although the alga-Iytic effect of S. herbici-dovorans HY0210-AK1 that in stationary growth phase was somewhat pronounced at the first time of inoculation. When S. herbicidovorans HY0210-AK1 was inoculated was inoculated with $1\times 10^{8}$ CFU $ml^{-1}$ together with A cylindrica NIES-19, the bacterium proliferated and caused algal lysis. A. cylindrica NIES-19 died when S. herbicidovorans HY0210 AKl was added to the algal culture but not when duly the filtrates from the bacterial culture was added. This suggests that extracellular substances are not responsible for inhibition of A. cylindrica NIES-19 and that algal Iysis largely attributed to direct interaction between S. herbicidovorans HY0210-AK1 and A. cylindrica NIES-19. The alga-lytic bacterium HY0210-AK1 caused cell lysis and death of three strain of Micro-cystis aeruginosa, but revealed no alga-Iytic effects on the Stephanodiscus hantzschii.

The change of CBF(cerebral blood flow) of CVA patients by oriental medical treatment - Focused on Brain SPECT results - (뇌졸중환자(腦卒中患者)에 있어서 치료경과(治療經過)에 따른 뇌혈류(腦血流) 변화(變化) - Brain SPECT 결과(結果)를 중심(中心)으로 -)

  • Kang, Hwa-Jeong;Hong, Seok;Kim, Jong-Seok;Song, Ho-Chon;Bum, Hee-Seung;Jeon, Sang-Yun
    • The Journal of Internal Korean Medicine
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    • v.21 no.1
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    • pp.39-45
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    • 2000
  • Object : SPECT which can visualize the distribution of CBF was operated to find the basic evidence by objective and scientific inspection on the fact that how the oriental medical treatment for stroke patients can effect CBF. Method : This study made 18 cases an object of research. These patients came to the Dongshin Univ. Oriental Medical Hospical within 5 days from the first attack, were diagnosed as stroke from Brain CT and MAl and were in the hospital for over 4 weeks at least. They were taken acupunture treatment, negative technique and herbal medication. And this study operated SPECT at the instance of admission and at the 4th week after admission 2 times and compared the change of CBF. Results : I operated SPECT on 18 CVA patients and got a result on the change of blood supplies in brain as follows; In the 2nd SPECT compared with 1st, out of the 1st and 2nd SPECT, there are 10 cases(55.6%) of increase and 8 cases (44.4%) of decrease. According to L/Cb11 evauation standard, the 1 st and the 2nd changes of blood supplies in SPECT shows decrese from $0.830{\pm}0.071$ to $0.801{\pm}0.067$. On the other hand, according to L/C standard shows a minute increase from $0.894{\pm}0.079$ to $0.895{\pm}0.091$. But there is nothing meaningful. I treated patients' group with risk factors and the other patients' group without risk factors and observed the changes of blood supplies respectively. And therefore Patients' group without risk factors shows an meaningful increase of blood supplies from $0.835{\pm}0.076$ to $0.796{\pm}0.069$ L/Cbll and also an increase from $0.921{\pm}0.029$ to $0.939{\pm}0.029$ by L/C. But this result by L/C is not significant. Conclusion : As mentioned above, I treated CVA patients through oriental medical therapies using SPECT and researched the changes of blood supplies in their brains. But I could' t get any meaningful result. However, I think only after solving some problems in this treatment and quantifing the changes of blood supplies, this results can be the standard of scientific examination about oriental medical treatments.

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A study on Supply Extension Device of AED (AED의 보급 확대 방안에 관한 연구)

  • Koh, Jae-Moon;Kim, Young-Ho;Han, Sang-Hak
    • The Korean Journal of Emergency Medical Services
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    • v.9 no.2
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    • pp.147-168
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    • 2005
  • It examined the doubt point which AED motive relates until now, the AED should have bought a life how, present address of our country site pre-hospital care, comparison it tried to observe the advanced nation instance back. Gist of this research the AED important cold region once compared to informed to how many cardiac arrest patient, against him the what kind of preparation wanted informing the necessary cold region. It soaks simultaneously but the AED motive is widely supplied distant in future and it is generality and it is feeble but it wanted doing one morning. The habit difference of an American who does of course meat diet mainly and a Korean is many and it compares in the United States and the cardiac arrest patient comparison occurs holds a point few. To become Western anger but and be caused by with thin dietary life, stanching bleeding cung, with the fact that the heart attack is increasing rapidly with the hyperextension. It is a talk which anyone it knows all. The major league most Choi huy Sub in condition will catch the ball which floats and the multi co-player and to collide when falling down, the medical device which is committed with emergency aid is AED motive. From the United States subway station and the shopping which are a public place on the baseball field outside the jar which it will drive, the museum and the school, easily there is it will be able to discover the AED from the court of justice back. The Pittsburg university the students per the individual $30 the core phyey were receiving the smallness lifestyle alcoholic beverage and a AED motive actual training with mercy of degree. From the United States distant in future the AED motive is sold even from the retail store and. From our country like this plan government offices temporary disposal education from from 119 fire fighters emergency structure company in fire fighting government employee and nursing must magnify a former enterprise rainy spell in summer multi temporary disposal education with the head which it will burn with the head. This plan in early rising will be able to become fixed in Korea it forecasts with the fact that. The research which it sees it leads and like the United States to some day become fixed even from our country to believe and suspicion it is not and in the people in approach ease one AED supply plan fire fighting government employees stand in the first and feed with the fact that must be positive at this enterprise they become.

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A Comparative Study on Each Nation's Counter terrorism Organization and Function (각국의 테러대응 조직과 기능의 비교 연구)

  • Kwon, Jeong-Hoon;Kim, Tae-Hwan
    • Korean Security Journal
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    • no.20
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    • pp.45-69
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    • 2009
  • This study is to present effective and rational strategies by comparing and analyzing plans of some nations such as the United States, Britain, Germany and Japan against terrorism. Nations mentioned above have made alliance to prevent the possible terrorism after 9.11 attack and performed various tasks efficiently. The result of this study is summarized as follows. First, it is required that there should be an integrated system which works properly. Each nation has not distinguished natural disaster from man-made one based on the damage and the abilities of authorities to deal with. On the other hand, South Korea tells two disasters according to causes and runs distributed systems in which each government division performs its duties to manage each disaster. Accordingly, in economic terms, it is much more effective to provide integrated counter terrorism, not distributed one. Second, information sharing must be stimulated. To take actions quickly when an accident occurs, the government needs to have united and integrative systems, which make it prepare for various types of terrorism well. In addition, it is necessary for a government-related organization to tie up with other channels for collecting, analyzing and sharing information. For this, integrative systems for terrorism should be taken into consideration.

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Studies on the Qualitative and Quantitative Damage of Sudangrass In fected with Leaf Blight ( Helminthosporium turcium PASS ) (매문병 ( Helminthosporium turcium PASS ) 에 감염된 수단그라스의 양적.질적 피해에 관한 연구)

  • 이상범;김정갑;김봉구;한흥전;양종성
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.6 no.1
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    • pp.65-70
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    • 1986
  • This experiment was carried out to identify the main pathogens infected with Piper sudangrass and to evaluate the qualitative and quantitative damage of the plants infected with leaf blight (Helminthosporium turcicum PASS) under different levels of nitrogen fertilizer (20, 30 and 40 kg/10a). The experiment was design as a randomized block design with 4 replications at experimental field of Livestock Experiment Station in Suweon, 1984. The results obtained are summarized as follows: 1. The main fungi isolated from sudangrass were identified as Helminthoporium turcicum and Collectotricum graminicolum, but 1 species fungus was not identified. 2. Leaf blight was first found on June 20 and appeared extremely in the regrowth plants from July to September. The rate of attack was associated with increasing of nitrogen fertilization (P<0.01). 3. Fresh and dry matter yields were as much as 47 and 38 percentage lower in leaf blight infected plants (disease severity: V) than those of no visible infection. 4. Concentrations of crude fat and crude protein were decreased in the plants infected with Helminthosporium leaf blight, but lignin content was increased. Dry matter and organic matter digestibility of the plants were negative correlated with the infection of leaf blight(P<0.01).

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The Necessity of A Cognitive-scientific Analysis on A Security threat Act - The Foundation for A Establishment of The Scientific Preventive Social-security Countermeasure - (경호위해행위에 대한 인지과학적 분석의 필요성 고찰 - 과학적 예방적 사회안전 대책 수립을 위한 기초 -)

  • Kim, Doo-Hyun;Son, Ji-Young
    • Korean Security Journal
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    • no.17
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    • pp.33-51
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    • 2008
  • According to dictionary, the meaning of protection is "guard and protect" that means protecting the Protectee's safety in case of sudden attack or various accident and Security means all protecting activity including Protectee and place where he is in or will be as comprehensively meaning of safe. As you see in the definition, Protection and security is the act to protect or will to protect from a security-threat act. A security-threat act can be discussed in the range of the concept of a criminal act in Criminal Law. A security-threat act is based on criminal act in Criminal Law, we are going to review such a security-threat act in a point of view in a sphere of learning in today's remarkable a brain-neuro science and cognitive science based on cognitive psychology, and to use an analysis on such a security-threat act to make a foundation for a establishment of the scientific preventive social security countermeasure. To do so, First of all we are going to review a security-threat act based on criminal act in Criminal Law in a point of protection police logic view. Next, we are going to introduce how cognitive science understand about act of man before we analyse a threat act as one of an act of man in cognitive science point of view. Finally, we are going to discuss the need of cognitive scientific analyse in order to establish the Scientific Preventive Social-security Countermeasure at the same time we are going to analyse a threat act in a cognitive scientific view.

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Estimation of Longitudinal Dynamic Stability Derivatives for a Tailless Aircraft Using Dynamic Mesh Method (Dynamic Mesh 기법을 활용한 무미익 비행체 종축 동안정 미계수 예측)

  • Chung, Hyoung-Seog;Yang, Kwang-Jin;Kwon, Ky-Beom;Lee, Ho-Keun;Kim, Sun-Tae;Lee, Myung-Sup;Reu, Taekyu
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.3
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    • pp.232-242
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    • 2015
  • For stealth performance consideration, many UAV designs are adopting tailless lambda-shaped configurations which are likely to have unsteady dynamic characteristics. In order to control such UAVs through automatic flight control system, more accurate estimation of dynamic stability derivatives becomes essential. In this paper, dynamic stability derivatives of a tailless lambda-shaped UAV are estimated through numerically simulated forced oscillation method incorporating dynamic mesh technique. First, the methodology is validated by benchmarking the CFD results against previously published experimental results of the Standard Dynamics Model(SDM). The dependency of initial angle of attack, oscillation frequency and oscillation magnitude on the dynamic stability derivatives of a tailless UAV configuration is then studied. The results show reasonable agreements with experimental reference data and prove the validity and efficiency of the concept of using CFD to estimate the dynamic derivatives.

EFFECTS OF AMYLASE ON THE DEMINERALIZATION IN HYDROXYAPATITE (Amylase가 Hydroxyapatite 탈회에 미치는 영향)

  • Lee, In-Hwan;Seo, Jeong-Taeg;Choi, Byung-Jai;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.2
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    • pp.335-351
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    • 1998
  • Salivary proteins which are produced in the saliary acinar cells have been known to be involved in the Calcium and phosphate metabolism. The acquired pellicle resulting from such metabolism is considered as a secondary defence membrane against tooth caries. In this respect, some proteins included in saliva probably play an important role in the prevention of demineralization in enamel. On the other hand, fluoride has long been known to prevent the demineralization of enamel by the inhibition of the growth of Streptococcus mutans(S. mutans) and by the chemical reaction with calcium and phosphate, Therefore, I have examined the roles of amylase and albumin in the demineralization of enamel and compared these preteins with fluoride in terms of anticariogenic effect. 1. The demineralization caused by S. mutans occurred slowly and progressively for the first 60 min, then the rate of demineralization was accelerated afterwards. 2. pH decreased continuously during the entire period of each experiment. 3. The demineralization was significantly inhibited by the preteatment of amylase and fluoride but albumin had little effect on it. 4. An addition of 0.1 mM lactic acid (final concentration 0.1 ${\mu}M$) caused a rapid increase in calcium concentration reaching a maximum within 10 min. 5. pH decreased rapidly by the addition of 0.1 mM lactic acid and reached a minimum within a few seconds followed by an increase in pH. pH reaced a plateu with 10 min. 6. Fluoride, amylase and albumin played little role in the 0.1 mM lactic acid-induced demineralization. 7. A slow infusion of 0.1 M lactic acid at a rate of 5 ${\mu}l/min$ caused a slower increase in calcium concentration compared with the bolus addition of lactic acid. 8. Fluoride had an inhibitory effect on the calcium release caused by slow infusion of lactic acid while amylase and albumin had no effect on it. These results suggest that fluoride inhibits demineralization by protecting the HA from the acid attack whereas amylase has a direct effect on S. mutans to prevent demineralization.

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