• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.28 no.5
• /
• pp.1161-1167
• /
• 2018

In order to cope with dramatically increasing malware variant, malware classification research is getting diversified. Recent research tend to grasp individual limits of existing malware analysis technology (static/dynamic), and to change each method into "hybrid analysis", which is to mix different methods into one. Futhermore, it is applying machine learning to identify malware variant more accurately, which are difficult to classify. However, accuracy and scalability of trade-off problems that occur when using all kinds of methods are not yet to be solved, and it is still an important issue in the field of malware research. Therefore, to supplement and to solve the problems of the original malware classification research, we are focusing on developing a new malware classification system in this research.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.2
• /
• pp.321-330
• /
• 2015

There have been found many modified malwares which could avoid detection simply by replacing a sequence of characters or a part of code. Since the existing anti-virus program performs signature-based analysis, it is difficult to detect a malware which is slightly different from the well-known malware. This paper suggests a method of detecting modified malwares by extending a hash-value based code comparison. We generated hash values for individual functions and individual code blocks as well as the whole code, and thus use those values to find whether a pair of codes are similar in a certain degree. We also eliminated some numeric data such as constant and address before generating hash values to avoid incorrectness incurred from them. We found that the suggested method could effectively find inherent similarity between original malware and its derived ones.

• Journal of Forest and Environmental Science
• /
• v.22 no.1
• /
• pp.18-26
• /
• 2006

The study was carried out to investigate the flora and stand structure in southwest slope of Mt. Chukryoung from March to October, 2005. As a result of that, vascular plants were 87 families, 268 genera, 399 species, 1 subspecies, 53 varieties, 4 formae and 457 taxa in all: Korean endemic plants were 11 families, 14 genera, 14 species and 14 taxa in all: rare or endangered plants were 8 families, 12 genera, 13 species and 13 taxa in all: naturalized plants were 8 families, 14 genera, 15 species, 1 varieties and 16 taxa in all. The stand structure analysis showed that: canopy was covered with Quercus mongolica. sub-canopy was covered with Styrax obassia, Euonymus oxyphyllus, Acer pseudo-sieboldianum and Quercus mongolica.

• Animal Systematics, Evolution and Diversity
• /
• v.8 no.1
• /
• pp.35-56
• /
• 1992

The systematic studyof freshwater rotifers was conducted on the materials collected from 205 sites in South Korea. As a result, 1 species, 9 subspecies, 2 varieties and 6 forms of two genera. Brachionus and platyas in Family Brachionidae were identified, of Which , 1 subspecies and 4 forms are new to the Korean fauna: Brachionus urceolaris bennini , B. angularis f. bidens , B. quadridentatus, f. rhenanus, B. forficula f. minor, and B. forficula f. angularis. Total 134 speices, 15 subspecies, 9 varieties and 9 forms representing 14 families 40 genera are now recorded from Korea by adding the 1 subspecies and 4 forms newly described in the present paper.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.1
• /
• pp.129-137
• /
• 2016

Transmission Control Protocol as a transport layer protocol provides steady data transfer service. There are some serious concerns about the performance of TCP over diverse networks. The vital concern in TCP network environment is congestion which may occur due to quick transmission rates or because of large number of new connections entering the network at the same time. Size of queues in routers grows thus resulting in packet drops. Retransmission of the dropped packets, and reduced throughput can prove costly. Explicit Congestion Notification (ECN) in conjunction with Active Queue Management mechanisms (AQM) such as Random early detection (RED) is used for packet marking rather than dropping. In IP packet header ECN bits can be added as a sign of congestion thus avoiding needless packet drops. The proposed ECN and AQM mechanism can be implemented with help of ns2 simulator and the performance can be tested on different TCP variants.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.6 no.1
• /
• pp.1-10
• /
• 2004

The climate of Minamiakikawa forest in Japan is similar to that of Mt. Jiri in South Korea. There is a large development plan for Minamiakikawa forest, and a change in the species composition is expected. This study was initiated to compare forest transition caused by artificial perturbations in Korea and Japan. Long-term field observations on species composition are reported. We found 98 families, 231 genera, 315 species, 29 varieties, and 8 races, making a total of 352 classification groups of higher plants in the Minamiakikawa forest area. Among them, 11 families, 12 species and 2 varieties are rare or endangered. The study area is dominated by Cryptomerica japonica and Chamaecyparis obtusa. The time and restoration effects on secondary and latent forestation consider the development of the Quercus mongolica community, the Quercus serrata community, and deciduous-broadleaved tree ascension. This indicates that the forest has been restored to Abies firma, Pinus densiflora or Cryptomeria japonica and Fagus japonica, which is considered latent natural forestation of the area in a natural transfer.

• Journal of Wetlands Research
• /
• v.12 no.3
• /
• pp.145-153
• /
• 2010

An-yang stream is a branch stream connecting to Han river and regarded as a national stream. This study chose the representative stream of An-yang and identified vegetation and flora. The ecological survey aimed at identifying indicator of urban streams for measuring to protect urban areas and to promote wetland conservation. A total of 266 species were identified into 35 Orders, 78 Families. The introduced species of Sicyo angulatus need a special treatment to reduce the population. The wetland vegetation is quite various and we suggested 11 different vegetation zones depending on introduced species and amenity between human and nature, This will lead to blue-network to crease favorable environment and manage important species for this region.

• Korean Journal of Environment and Ecology
• /
• v.18 no.1
• /
• pp.18-41
• /
• 2004

Sonjook island is located Samsan-myeon, Yeosu-si, Jeollanam-do. All of field information was collected from January 2001 to November 2002. The vascular plants recorded as total 584 taxa, 5 forms, 60 varieties, 519 species, 365 geneta, 113 families. Sonjook islands shows the typical vegetations including the lower area of temperate region of Korean peninsula and evergreen broad-leaved forests, Pinus thunbergii forest. The Korean endemic plants were recorded as 13 taxa (5 variety, 8 species, 10 genera, 10 families), 4 taxa as rare and endangered plants (Psilotum nudum (L.) Griseb., Milletia japoniea A. Gray, Arisaema negishii Makino, Sarcanthus scolopendrifolius Makino). The naturalized plants were 23 taxa (20 genera, 9 families, 8.2％ among the total naturalized plants in Korea. This area is ecologically important place that Korea endemic plant, rare and endangered plants ranges much than area. On the one hand, threat from degraded by environmental pollution that share of naturalized plant rises gradually augment. Strong conservation policy and development control should be considered.

• Korean Journal of Plant Resources
• /
• v.10 no.4
• /
• pp.275-291
• /
• 1997

Floristic composition and medicinal plant resources were investigated in six regions, Mt. Sorak, Mt. Jumbong, Mt. Odae, Mt. Hwaak, Mt. Taebaek, and Mt. Bangtae, represent in Kangwon province. This study was conducted from December. 1995 to October, 1997. Vascular plants in investigated regions were composed of 118 families . 529 genera, 1,138 species, 7 subspecies, 223 varieties and 43 fromae, totaling 1,411 taxa. This taxa was correspond to 34.7% of Korean flora, 4,071 taxa (Lee, 1996b),and 73.8% of Kangwon province flora, 1,913 taxa (Kangwondo, 1996), respectively. Among them, medicinal plant resources was composed of 98 families, 238 genera, 337 species, 63. varieties, and 16 formae, totaling 416 taxa (29.5% of investigated 1.411 taxa). Medicinal plant resources in each regions were distributed ranging from 211(31.4%) to 285(33.1%) taxa.

• Korean Journal of Plant Resources
• /
• v.20 no.4
• /
• pp.312-320
• /
• 2007

The resource plants at the reclaimed seaside in Songdo was listed 170 taxa: 39 families, 113 genera, 144 species, 23 varieties, 2 forms and 1 hybrid. In those, woody plants were 18 taxa (10.6%) and herbaceous plants were 152 taxa (89.4%). Among 170 taxa listed was confirmed 107 taxa of edible plants (62.9%), 99 taxa of medicinal plants (58.2%), 55 taxa of ornamental plants (32.4%) and 77 taxa of the others (45.3%). Salt plants (Including dune plants) consists of 12 taxa (Scirpus planiculmis, Sllaeda japonica, Artemisia scoparia, Scorzonera albicaulis, etc.). Specific plants by floral region were total 5 taxa; Vicia bungei in class IV, Koelreuteria paniculata in class III, Grewia biloba var. parviflora, Lysimachia fortunei, Rhapontica uniflora in class I. The naturalized plants in this site were 11 families, 27 genera, 37 species, 1 varieties, 38 taxa and naturalization rate was 22.4% of all 170 taxa resource plants.