• Title/Summary/Keyword: 백트랙

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A Study on Signature-based Wireless Intrusion Detection Systems (시그니처 기반의 무선 침입 탐지 시스템에 관한 연구)

  • Park, Sang-No;Kim, A-Yong;Jung, Hoe-Kyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.5
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    • pp.1122-1127
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    • 2014
  • WLAN is affordability, flexibility, and ease of installation, use the smart device due to the dissemination and the AP (Access Point) to the simplification of the Office building, store, at school. Wi-Fi radio waves because it uses the medium of air transport to reach areas where security threats are always exposed to illegal AP installation, policy violations AP, packet monitoring, AP illegal access, external and service access, wireless network sharing, MAC address, such as a new security threat to steal. In this paper, signature-based of wireless intrusion detection system for Snort to suggest how to develop. The public can use hacking tools and conduct a mock hacking, Snort detects an attack of hacking tools to verify from experimental verification of the suitability of the thesis throughout.

Heuristic Backtrack Search Algorithm for Energy-efficient Clustering in Wireless Sensor Networks (무선 센서 네트웍에서 에너지 효율적인 집단화를 위한 경험적 백트랙 탐색 알고리즘)

  • Sohn, Surg-Won
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.5
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    • pp.219-227
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    • 2008
  • As found in research on constraint satisfaction problems, the choice of variable ordering heuristics is crucial for effective solving of constraint optimization problems. For the special problems such as energy-efficient clustering in heterogeneous wireless sensor networks, in which cluster heads have an inclination to be near a base station, we propose a new approach based on the static preferences variable orderings and provide a pnode heuristic algorithm for a specific application. The pnode algorithm selects the next variable with the highest Preference. In our problem, the preference becomes higher when the cluster heads are closer to the optimal region, which can be obtained a Priori due to the characteristic of the problem. Since cluster heads are the most dominant sources of Power consumption in the cluster-based sensor networks, we seek to minimize energy consumption by minimizing the maximum energy dissipation at each cluster heads as well as sensor nodes. Simulation results indicate that the proposed approach is more efficient than other methods for solving constraint optimization problems with static preferences.

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Geochronology and Cooling history of the Mesozoic Granite Plutons in the Central Part of the Ogcheon Fold Belt, South Korea (남한 습곡대 중앙부의 중생대 화강암 질암의 생선년대와 냉각사)

  • Myung-Shik JIN
    • The Journal of the Petrological Society of Korea
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    • v.4 no.2
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    • pp.153-167
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    • 1995
  • Emplacement ages for the granite plutons of the Jurassic and the Cretaceous times in the central Ogcheom Fold Belt were determined by Rb-Sr whole rock and mineral isocheon methods. In addition mineral ages for the plutons were determined by K-Ar and fission track methods. In turn, thermal histories and uplifting rates of the granitic bodies are elucidated from the isotopic ages. The Jecheon(~203 Ma) and Mungyeong(at lest~200 Ma) granites of the Jurassic and the Muamsa, Wolagsan and Daeyasan granites(~110 Ma) of the Cretaceous show high strontium initial ratios [$(^{87}Sr/^{86}Sr)_1$0.7100],suggesting that the granitic magmas have been generated by partial melting of crustal materials (S-type), or by mixing of mantle and crustal materials. Only mineral ages of the Sogrisan and Hyeongjebong granites (~90 Ma) were determined by K-Ar method, and petrogenesis of them were not defined yet. The two Jurassic granite plutons were cooled rapidly down to $300^{\circ}C$, right after the plutons were slowly cooled down since then, due to their deep emplacment. During the Middle Cretaceous period, the Jurassic Mungyeong granitic pluton was intruded and thermally affected much by the surrounding Wolagsan and Daeyasan granites. Accordingly the Rb-Sr mineral age, K-Ar hornblende and biotite ages of the Mungyeong granite appear to be reduced or reset due to the thermal effects above their blocking temperatures. All the cretaceous granites have been cooled much ore simply and rapidly down than the Jurassic ones below $300^{\circ}C$, owing to their shallow emplacement.

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Effect of class Blog Activity on self-esteem for elementary students (학급 블로그 활동이 초등학교 학생들의 자아 존중감에 미치는 영향)

  • Yoo, Seoung-Han;Sung, Young-Hun;Lee, Jae-Inn
    • Journal of The Korean Association of Information Education
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    • v.9 no.2
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    • pp.177-185
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    • 2005
  • The latest BLOG is highlighted both freely writing about the personal life and the tool which is maintaining friendly relations with many people by trackback. In this study, this BLOG system is designed for improving self-esteem in the class by using these characteristic of BLOG. the internet activity of students and their normal activity in the classroom connects with The Star-Gift-Shop module. This module induces students to an active BLOG, activity with interest. as a result of this activity in the class BLOG system, students improves their computer application ability and confidence of them. Which is effected teacher's efficient classroom management.

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A study on story generation model of blogging (블로그 글쓰기의 스토리생성 모델 연구)

  • Yun, Hyun-Jung
    • Journal of Digital Contents Society
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    • v.15 no.1
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    • pp.29-38
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    • 2014
  • The purpose of this study is to analyze story generation model of blogging. This study considers the structural factors like RSS, Trackback of the blog that generate stories. RSS pushes stories and this makes 'Story Unit'. By contrast, Trackback pulls stories and this makes 'Story extension'. By applying the concept of C. S. Peirce's "interpretant" for analysis process of story generation, story transformation, and story circulation on a blog, this study examines the meaning that each process create. This study suggests the process of story generation model on blogging as an integrated symbol and presents the model in storytelling perspective.

Revised Fission-track Ages and Chronostratigraphies of the Miocene Basin-fill Volcanics and Basements, SE Korea (한국 동남부 마이오세 분지 화산암과 기반암의 피션트랙 연대 재검토와 연대층서 고찰)

  • Shin, Seong-Cheon
    • The Journal of the Petrological Society of Korea
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    • v.22 no.2
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    • pp.83-115
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    • 2013
  • Erroneous fission-track (FT) ages caused by an inappropriate calibration in the initial stage of FT dating were redefined by re-experiments and zeta calibration using duplicate samples. Revised FT zircon ages newly define the formation ages of Yucheon Group rhyolitic-dacitic tuffs as Late Cretaceous to Early Paleocene ($78{\pm}4$ Ma to $65{\pm}2$ Ma) and Gokgangdong rhyolitic tuff as Early Eocene ($52.1{\pm}2.3$ Ma). In case of the Early Miocene volcanics, FT zircon ages from a dacitic tuff of the upper Hyodongri Volcanics ($21.6{\pm}1.4$ Ma) and a dacitic lava of the uppermost Beomgokri Volcanics ($21.3{\pm}2.0$ Ma) define chronostratigraphies of the upper Beomgokri Group, respectively in the southern Eoil Basin and in the Waeup Basin. A FT zircon age ($19.8{\pm}1.6$ Ma) from the Geumori dacitic tuff defines the time of later dacitic eruption in the Janggi Basin. Based on FT zircon ages for dacitic rocks and previous age data (mostly K-Ar whole-rock, partly Ar-Ar) for basaltic-andesitic rocks, reference ages are recommended as guides for stratigraphic correlations of the Miocene volcanics and basements in SE Korea. The times of accumulation of basin-fill sediments are also deduced from ages of related volcanics. Recommended reference ages are well matched to the whole stratigraphic sequences despite complicated basin structures and a relative short time-span. The Beomgokri Group evidently predates the Janggi Group in the Eoil-Waeup basins, while it is placed at an overlapped time-level along with the earlier Janggi Group in the Janggi Basin. Therefore, the two groups cannot be uniformly defined in a sequential order. The Janggi Group of the Janggi Basin can be evidently subdivided by ca. 20 Ma-basis into two parts, i.e., the earlier (23-20 Ma) andesitic-dacitic and later (20-18 Ma) basaltic strata.

Cooling and Thermal Histories of Cretaceous-Paleogene Granites from Different Fault-bounded Blocks, SE Korean Peninsula: Fission-track Thermochronological Evidences (한반도 동남부의 주단층대에 의해 구분된 지질블록별 백악기-고제3기 화강암의 차별적 냉각-지열 이력: 피션트랙 열연대학적 증거)

  • Shin, Seong-Cheon
    • The Journal of the Petrological Society of Korea
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    • v.21 no.3
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    • pp.335-365
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    • 2012
  • Fission-track (FT) thermochronological records from SE Korean Cretaceous-Paleogene granitic plutons in different fault-bounded blocks reveal contrasting cooling and later thermal histories. Overall cooling patterns are represented by a monotonous (J-shaped) curve in most plutons except some Cretaceous granites retaining a complicated (N-shaped) path due to post-reset re-cooling. Discriminative cooling rates over different temperature ranges can be explained for individual plutons with respect to relative pluton sizes, differences in initial heat loss depending on country rocks, and the presence and proximity of later igneous activity. Even within a single batholith, cooling times for different isotherms were roughly contemporaneous with respect to positions. Insignificant deviations in cooling ages from two different plutons in succession across the Yangsan fault may suggest their contemporaneity before major horizontal fault movement. The extent of later thermal rise recorded locally along the Yangsan and Dongnae fault zones were reached the Apatite Partial Stability Zone ($70-125^{\circ}C$), but did not exceed $200^{\circ}C$. Thermal alteration from fractured zones in the Yangsan-Ulsan fault junction may suggest a thermal reset above $290^{\circ}C$ resulting a complete reset in FT sphene age (31 Ma), caused by a tectonic subsidence in Early Oligocene. A consistency in FT zircon/apatite ages (24 Ma) may imply a sudden rapid cooling over $200-105^{\circ}C$, plausibly related to the abrupt tectonic uplift of the Pohang-Gampo Block including the fault junction in Late Oligocene. A remarkable trend of lower cooling ages for $300-200-100^{\circ}C$ isotherms (i.e., 19% for FT sphene and K-Ar biotite; 20% for FT zircon; 27% for FT apatite) from the east of the Ulsan fault (Pohang-Gampo Block) comparing to the west of the fault may be attributed to retarded cooling times from the Paleogene granites and also reflected by their partially-reduced apatite ages due to later thermal effects.

An Efficient Smoothing Algorithm Using the Change of Frame Sequence in GOP (GOP를 구성하는 프레임들의 순서 변경을 이용한 효율적인 스무딩 알고리즘)

  • Lee, Myoun-Jae
    • Journal of Korea Game Society
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    • v.6 no.2
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    • pp.51-60
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    • 2006
  • Smoothing is a transmission plan where variable rate video data is converted to a constant bit rate stream. Among them are CBA, MCBA, MVBA, PCRTT and others. But, in these algorithm, a transmission plan is made in according to stored frame sequence in these algorithms. In case that the number of bytes in frames in GOP differs greatly each other, this may cause unnecessary transmission rate changes and may require high transmission rates abruptly when frame's byte is large. In result, it is difficult to use efficient network resource. In this paper, we proposed a smoothing algorithm that find the optimal frame sequence in short time by using backtracking method and smoothing's structure for the proposed smoothing algorithm. This algorithm decides the sequence of frames which requires the lowest variance of frame's bytes in GOP and make a transmission plan. In order to show the performance, we compared with MVBA algorithm by various evaluation factors such as the number of rate changes, peak rate, rate variability.

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Web based PBL Teaching·Learning Development Model for Medical Education (의료정보 교육을 위한 웹기반 PBL 교수·학습 콘텐츠 개발 모형)

  • Choo, Hyun-Jae;Park, Joo-Hee
    • The Journal of the Korea Contents Association
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    • v.10 no.10
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    • pp.246-254
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    • 2010
  • Recent changes in medical environment are based on technology such as internet. As most hospitals require the change and the adaptation of medical, medical information experts are more needed. In this study, we developed web based PBL model and applied it to the students majoring in medical information system. The developed web-PBL model focuses on learner's online learning activities to enhance collaborative learning and self-directed learning by using online learning tools. At the result of the research, We found that the students' course evaluation somewhat increased compared to the previous class and the students positively perceived on PBL model. Moreover, this study showed that using blog as a online learning tool was a good way to enhance cooperative learning.

A Multibit Tree Bitmap based Packet Classification (멀티 비트 트리 비트맵 기반 패킷 분류)

  • 최병철;이정태
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.3B
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    • pp.339-348
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    • 2004
  • Packet classification is an important factor to support various services such as QoS guarantee and VPN for users in Internet. Packet classification is a searching process for best matching rule on rule tables by employing multi-field such as source address, protocol, and port number as well as destination address in If header. In this paper, we propose hardware based packet classification algorithm by employing tree bitmap of multi-bit trio. We divided prefixes of searching fields and rule into multi-bit stride, and perform a rule searching with multi-bit of fixed size. The proposed scheme can reduce the access times taking for rule search by employing indexing key in a fixed size of upper bits of rule prefixes. We also employ a marker prefixes in order to remove backtracking during searching a rule. In this paper, we generate two dimensional random rule set of source address and destination address using routing tables provided by IPMA Project, and compare its memory usages and performance.