• Title/Summary/Keyword: Worms

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An On-the-fly Filtering Technique for Reducing Packet Inspection Overhead Against Worms and DDoS Attack (웜이나 DDoS 공격에 대한 패킷 검사 부하를 줄이는 간편 필터링 기법)

  • Ryu, Jin-Hyong;Lee, Jea-Kook;Kim, Sang-Min;Kim, Hyong-Shik
    • Proceedings of the Korean Information Science Society Conference
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    • 2008.06d
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    • pp.57-61
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    • 2008
  • 대부분의 보안 장비들은 웜이나 DDoS 공격들을 탐지하거나 차단하기 위하여 시그너쳐(signature) 검사방법을 이용한다. 웜이나 DDoS 공격은 네트워크에 부하를 주기 때문에 정상 서비스의 이용을 제한하고 심지어 보안장비를 동작하지 못하게 함으로써 네트워크를 마비시킬 수 있다. 본 논문에서는 패킷 유입량이 보안장비가 처리할 수 있는 범위를 벗어나면, 간편 필터를 이용하여 패킷 검사 오버헤드를 줄여 보안장비들의 가용성을 높이는 기법을 제안한다. 그리고 기존의 대표적인 웜들과 DDoS 공격 성향을 조사하여 타당성을 보인다.

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Faunistic survey on freshwater annelids from Korea

  • Lee, Jeounghee;Jung, Jongwoo
    • Journal of Species Research
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    • v.5 no.3
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    • pp.279-288
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    • 2016
  • Aquatic oligochaete plays an important role in freshwater ecosystem. These worms, therefore, have already been extensively studied around the world. But compared to other countries with East Asia, only 48 species of aquatic oligochaetes have been recorded in Korea. This is because taxonomic study of aquatic oligochaete is in just beginning stages. Our specimens of this study had been collected from eighteen locations in Korean peninsula. Analyzing them we identified twenty unrecorded species including one species of aelosomatid: Paranais orientalis, Pristina breviseta, P. notopora, P. foreli, P. synclites, Bratislavia prosetosa, Allonais gwaliorensis, Aulodrilus pluriseta, Limnodrilus neotropicus, L. maumeensis, L. amblysetus, Tubifex ignotus, Potamothrix cf. bedoti, P. bavaricus, Peipsidrilus cf. pusillus, Psammoryctides albicola, Varichaetadrilus vestibulatus, Tasserkidrilus cf. acapillatus, Propappus volki, Aeolosoma japonicum.

Comparison of DNase Activities from Infective Larvae vs Adult Worms of Haemonchus contortus (염전위충 감염자충과 성충의 DNase 활성 비교)

  • 곽동미
    • Journal of Veterinary Clinics
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    • v.21 no.3
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    • pp.248-252
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    • 2004
  • DNase activity from infective larvae of the parasitic nematode Haemonchus contortus was characterized and compared to that from whole worm. DNase activity from infective larvae was detected throughout pHs 4-10, but high activity was detected under acidic conditions. The activity was not inhibited by 10 mM EDTA at pH 5.0, but was significantly inhibited at pH 7.0. The activity produced DNA, fragments with mixtures of 3'-hydroxyls (OH) and 3'-phosphates (P) at each pH with predominance of 3'-P. A unique DNase activity at 37 kDa was identified from infective larvae on zymograms. The 37 kDa DNase was detected only at pH 5.0, but not at pH 7.0, and this activity was not inhibited by EDTA at pH 5.0. These characteristics of the 37 kDa infective larval DNase resemble those of classic acidic DNases (e.g., DNase II). In contrast, 34, 36 and 38.5 kDa DNase activities were shown to be specific for whole worm. This result demonstrated that DNases in H contortus are regulated during development.

Early and Uniform Maturation in Silkworm Bombyx mori L. by Phytoecdysteroid Extracted from a Plant of Family Caryophyllaceae

  • Trivedy, Kanika;Nair, K.Sashindran;Ramesh, M.;Gopal, Nisha;Kumar, S.Nirmal
    • International Journal of Industrial Entomology and Biomaterials
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    • v.7 no.1
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    • pp.65-68
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    • 2003
  • One of the biggest problems encountered during the last phase of silkworm rearing is non-uniform maturation of the silkworms especially during cooler months. Phytoecdysteroid (20-hydroxy ecdysone) was extracted in large-scale from a plant belongs to Caryophyllaceae and fed to silkworm larvae to test the effect of phytoecdysteroid. About 80% of the silkworms were ready for mounting by 18 hrs after treatment (when the treatment is done for uniform spinning), whereas in control batch only 37% worms were ready for mounting by the same time.

Image segmentation using adaptive MIN-MAX genetic clustering and fuzzy worm searching (자율 적응 최소-최대 유전 군집호와 퍼지 벌레 검색을 이용한 영상 영역화)

  • 하성욱;서석배;강대성
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.781-784
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    • 1998
  • An image segmentation approach based on the fuzzy worm searching and MIN-MAx clusterng algorithm is proposed in this paper. This algorithm deals with fuzzy worm value and min-max node at a gross scene level, which investigates the edge information including fuzzy worm action. But current segmentation methods based edge extraction methods generally need the mask information for the algebraic model, and take long run times at mask operation, wheras the proposed algorithm has single operation ccording to active searching of fuzzy worms. In addition, we also genetic min-max clustering using genetic algorithm to complete clustering and fuzyz searching on grey-histogram of image for the optimum solution, which can automatically determine the size of rnages and has both strong robust and speedy calculation. The simulation results showed that the proposed algorithm adaptively divided the quantized images in histogram region and performed single searching methods, significantly alleviating the increase of the computational load and the memory requirements.

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Worm evolution trend through Sobig worm variant (소빅 웜을 통한 웜 발전동향)

  • 박재우;김원호
    • Proceedings of the Korea Information Assurance Society Conference
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    • 2004.05a
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    • pp.175-180
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    • 2004
  • In early 2003, a worm called Sobig was found. Later, many of its variations were found, and win32.Sobig.F caused the most serious problems. This kind of simply modified worms (including those caused by the 'war' between Netsky vs. Beagle Worm) will be expected to cause many more problems. In this paper, we analyze the Sobig Worm and its variations. We, further, design a method that can expect future directions of modifications. We believe this will prevent serious loss such as we experienced on Jan 25.

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Acanthoparyphium tyosenense Infection in Great Knots and Turnstone on the Western Coast of Korea

  • Chung, Ok-Sik;Joo, Kyoung-Hwan;Lee, Woo-Shin
    • Journal of Ecology and Environment
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    • v.30 no.1
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    • pp.97-99
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    • 2007
  • Waders inhabiting an area in which A. tyosenense is endemic were examined to determine if they serve as reservoir hosts for the parasite. Of the waders examined, 4 individuals from 2 species were found to be hosts for 18 to 1820 adult worms. Common and velvet scoters, which are known to be the final hosts of A. tyosenense, are rare in the infected areas, while waders are prevalent and prey on the bivalves known to be intermediate hosts of A. tyosenense. Thus, from the experimental results and circumstances presented herein, we conclude that waders are definitive and reservoir hosts of A. tyosenense in nature.

A Case of Ancylostoma ceylanicum Infection Occurring in an Australian Soldier Returned from Solomon Islands

  • Speare, Rick;Bradbury, Richard Stewart;Croese, John
    • Parasites, Hosts and Diseases
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    • v.54 no.4
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    • pp.533-536
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    • 2016
  • A 26-year-old male member of the Australian Defense Force presented with a history of central abdominal pain of 4 weeks duration and peripheral eosinophilia consistent with eosinophilic enteritis. Acute hookworm disease was diagnosed as the cause. Adult worms recovered from feces after therapy with albendazole were morphologically consistent with Ancylostoma ceylanicum. As the patient had been deployed with the Regional Assistance Mission to Solomon Islands for 6 months prior to this presentation, it is very likely that the A. ceylanicum was acquired in Solomon Islands. Until now, it has been assumed that any Ancylostoma spp. recovered from humans in Solomon Islands is A. duodenale. However, this case demonstrates that human hookworm infection acquired in the Solomon Islands could be caused by A. ceylanicum.

The Distribution of Some Metazoan Parasites from Canary Rockfishes, Sebastes pinniger

  • Chun, Kae-Shik
    • Korean Journal of Environmental Biology
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    • v.21 no.2
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    • pp.177-180
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    • 2003
  • Four genera of metazoan parasites were recovered from 3 of 6 Sebastes pinniger examined during January 2003. Two hundred forty-five metazoan parasites were recovered. Trochopus trituba Sekerak and Arai, 1977 and Anisakis larvae were found to he infected S. finniger Gill and te be abundant in this rockfish. One hundred eleven worms of monogenean trematodes and 134 larval anisakine nematodes were also found in this fishes. Precise positions with regard to gills, fins, and gastrointestinal tracts were recorded on S. pinniger to determine distribution of metazoan parasites of Trochopus trituba, Anisakis simplex larva, Contracaecum sp. larva, and Pseudo terranova decipiens larva. The monogenean trematodes, T. trituba were attacked to the gill arches and fin, and the larval anisakine nematodes, A. simplex, Contracaecum sp.,and P. decipiens were found on the visceral organs such as intestine, omentum and stomach wall. The second gill arches were the most heavily infested and posterodorsal region of the gill arches contained most monegenenn trematodes. The nam site of infestation of larval anisakine nematodes were the intestine.

A case of gastric strongyloidiasis in a Korean patient

  • Kim, Jin;Joo, Hyun-Soo;Kim, Doo-Hong;Lim, Ho;Kang, Yu-Ho;Kim, Myung-Soo
    • Parasites, Hosts and Diseases
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    • v.41 no.1
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    • pp.63-67
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    • 2003
  • A 69-year-old Korean man was admitted to emergency room with complaints of abdominal pain, vomiting, and diarrhea, Laboratory tests revealed eosinophilia, anemia, hypoproteinemia, and hyponatremia. The gastric mucosa showed whitish mottled and slightly elevated lesions on the body angle of antrum. Microscopically, chronic gastritis with incomplete intestinal metaplasia was observed. Many adult worms, larvae, and eggs in cross sections were located in the crypts. Furthermore, the filariform larvae of Strongyloides stercoralis with a notched tail were detected through the culture.