• Title/Summary/Keyword: 사이중심도

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A Hybrid Model of Network Intrusion Detection System : Applying Packet based Machine Learning Algorithm to Misuse IDS for Better Performance (Misuse IDS의 성능 향상을 위한 패킷 단위 기계학습 알고리즘의 결합 모형)

  • Weon, Ill-Young;Song, Doo-Heon;Lee, Chang-Hoon
    • The KIPS Transactions:PartC
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    • v.11C no.3
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    • pp.301-308
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    • 2004
  • Misuse IDS is known to have an acceptable accuracy but suffers from high rates of false alarms. We show a behavior based alarm reduction with a memory-based machine learning technique. Our extended form of IBL, (XIBL) examines SNORT alarm signals if that signal is worthy sending signals to security manager. An experiment shows that there exists an apparent difference between true alarms and false alarms with respect to XIBL behavior This gives clear evidence that although an attack in the network consists of a sequence of packets, decisions over Individual packet can be used in conjunction with misuse IDS for better performance.

Design of a Ka-band Bandpass Filter Using LTCC Technology (LTCC 기술을 이용한 Ka-밴드 대역통과필터 설계)

  • 최병건;박철순
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.2A
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    • pp.214-217
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    • 2004
  • In this paper, a Ka-band LTCC (low temperature co-fired ceramic) narrow bandpass filter (BPF) is firstly presented. This BPF shows very narrow 3dB fractional bandwidth of 4.5 % centered at 28.7㎓. The advantages of multi-layered LTCC technology such as high integration and vertical stacking capabilities were employed to design three-dimensional interdigital end-coupled embedded microstrip narrow BPF. The difficulties in controlling the precise distance between two adjacent resonators in LTCC end-coupled BPF were overcome by locating the resonators on different layers. The measured insertion loss is 3dB at 28.7㎓, pass band is from 27.9 ㎓ to 29.2 ㎓, and the return loss in the pass band is less than 10 dB.

A Bluetooth Scatternet Reformation Algorithm based on Node Types (노드 형태에 따른 블루투스 스캐터넷 재형성 알고리즘)

  • Lee Han Wook;Kauh S. Ken
    • Journal of KIISE:Information Networking
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    • v.32 no.1
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    • pp.110-122
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    • 2005
  • Bluetooth has been reputed as a wireless networking technology supplying ad-hoc networks between digital devices. In particular, bluetooth scatternet is a most essential part for dynamic ad-hoc networks. But past researches on bluetooth scatternet has hardly treated dynamic scatternet environment. In this paper, we proposed a scatternet reformation algorithm for the case that some nodes escape from the scatternet. The proposed algorithm is a general algorithm which can be applied to many types of bluetooth scatternet regardless of the topology. The proposed algorithm has short reformation time delay because the process has only page process (not including inquiry process ). The algorithm is operated based on Recovery Node Vector which is composed of Recovery Master and Recovery Slave. In this paper, we performed the real hardware experiments for evaluating the performance of the proposed algorithm. In that experiments, we measured the reformation time and reformation probability. In comparison with the case including inquiry process, the proposed algorithm had the improvement in reformation time delay and we obtained high success rate over 97%.

Resampling Feedback Documents Using Overlapping Clusters (중첩 클러스터를 이용한 피드백 문서의 재샘플링 기법)

  • Lee, Kyung-Soon
    • The KIPS Transactions:PartB
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    • v.16B no.3
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    • pp.247-256
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    • 2009
  • Typical pseudo-relevance feedback methods assume the top-retrieved documents are relevant and use these pseudo-relevant documents to expand terms. The initial retrieval set can, however, contain a great deal of noise. In this paper, we present a cluster-based resampling method to select better pseudo-relevant documents based on the relevance model. The main idea is to use document clusters to find dominant documents for the initial retrieval set, and to repeatedly feed the documents to emphasize the core topics of a query. Experimental results on large-scale web TREC collections show significant improvements over the relevance model. For justification of the resampling approach, we examine relevance density of feedback documents. The resampling approach shows higher relevance density than the baseline relevance model on all collections, resulting in better retrieval accuracy in pseudo-relevance feedback. This result indicates that the proposed method is effective for pseudo-relevance feedback.

A Study on the Smoothing of Digital Elevation Model by Finite Element Method - in Mt. Sorak Area - (유한요소법에 의한 수치표고모델의 유형화에 관한 연구 -설악산 지역을 중심으로 -)

  • Choi, Seung Pil;Yang, In Tae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.3
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    • pp.163-171
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    • 1992
  • The narrow interal grid is effective in accuracy, but it is not able to make a densely grided sample, so that smoothing is requared. In digital elevation models, an application of the finite elements method is effective to smooth the undesired noise which is generated in aquisition of elevation data. And this is one of the simple and direct method to solve the problem for discontinuity of terrain. Therefore, the finite elements method is applied to study. In digital elevation model by appling the finite element, smoothing is affected by the height weight. In this study, the relation equation between elevation weight and standard deviation of smoothing was obstained as Y = 1900625 $X^4-312987.6$ $X^3+20330.72$ $X^2-578.6029$ X+12.63772 and from this function, Optimum elevation weight is 0.05.

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The Influence of Entrepreneurial Leadership on Team Performance -Focusing on the Mediating Role of Team Efficacy (기업가적 리더십이 팀 성과에 미치는 영향 - 팀 효능감의 매개효과를 중심으로)

  • Wang, Huan-Huan;LI, Yan-Nan;Kim, Jong-Kwan
    • Journal of Digital Convergence
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    • v.18 no.10
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    • pp.107-117
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    • 2020
  • With the advent of the Fourth Industrial Revolution, companies pursue innovation and opportunities, and corporate performance is also newly defined. As a result, the demand for new leadership is stronger. This paper conducted an empirical analysis to examine the role of team efficacy between entrepreneurial leadership and team performance. Using the SPSS 21.0 and AMOS 20.0 Statistics Package, 530 members in 79 work teams in China collected data was analyzed. The results showed that entrepreneurial leadership has a positive (+) effect on team performance, and team efficacy has a partial mediating effect between entrepreneurial leadership and team performance. This study deepened the understanding of entrepreneurial leadership and revealed the importance of entrepreneurial leadership in organizations. Future research can focus on multi-level research involving self-efficacy and individual entrepreneurial intent.

Theoretical Studies on the Cationic Polymerization Mechanism of Oxiranes (산촉매하의 옥시란 공중합에 관한 분자궤도론적 연구)

  • Young-Gu Cheun
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.461-468
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    • 1991
  • The cationic polymerizations of substituted oxiranes which have pendant energetic groups such as azido, and nitrato, are investigated theoretically using the semiempirical MNDO, and $AM_1$ methods. The nucleophilicity and basicity of substituted oxiranes can be explained by the negative charge on oxygen atom of oxiranes. The reactivity of propagation in the polymerization of oxiranes can be represented by the positive charge on carbon atom and the low LUMO energy of active species of oxiranes. Ring opening of the complexed cyclic oxonium ion to the open chain carbenium ion is expected computational stability of the oxonium and carbenium ion by 30∼40 kcal/mol favoring the carbenium ion. The relative equilibrium concentration of cyclic oxonium and open carbenium ions will be a major determinant of mechanism. The chain growth $SN_1$, mechanism will be at least as fast as that for $SN_2$ mechanism.

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Trend Analysis of Age Structure Ratio Change in Disaster Response Organization and Presenting the Criteria of Age Limit of Fire-fighting Field Activities -Focused on Firefighters in Seoul Metropolitan City- (재난대응조직 연령 구성비 변화 추이분석 및 구성원의 현장활동 한계연령 도출 -서울지역 현장활동 소방공무원을 중심으로-)

  • Park, Chanseok
    • Journal of the Society of Disaster Information
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    • v.10 no.3
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    • pp.466-480
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    • 2014
  • In addition to aging social problem, the problem of older age structure ratio in the fire service organization playing the leading role of the disaster response activities is also expected to be this serious situation. In the case of Seoul fire fighting organization, it is expected that the ratio of over the age 50 reaches 31% or 40% between from 10 to 15 years later from now on, but this will be a serious problem in the fire fighting personnel needing a healthy body and physical strength in the disaster situation unlike the civil servants of general staff. Therefore, the purpose of this study is to take measures that can adapt to a new disaster environment of Increasing proportion of the elderly population by presenting the criteria of age limit of fire fighting field activities to analyze the relevance of the ability to perform on-site activities and age of Seoul fire civil servants, by using three analysis criteria.

Detailed Flow Analysis of Helicopter Shrouded Tail Rotor in Hover Using an Unstructured Mesh Flow Solver (비정렬격자계를 이용한 헬리콥터 덮개 꼬리 로터의 제자리 비행 유동 해석)

  • Lee, Hui Dong;Gwon, O Jun;Gang, Hui Jeong;Ju, Jin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.5
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    • pp.1-9
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    • 2003
  • Detailed flow of a shrouded tail rotor in hover is studied by using a compressible inviscid flow solver on unstructured meshes. The numerical method is based on a cell-centered finite-volume discretization and an implicit Gauss-Seidel time integration. Numerical simulation is made for a single blade attached to the center body and guide by the duct by imposing a periodic boundary condition between adjacent rotor blades. The results show that the performance of an isolated rotor without shroud compares well with experiment. In case of a shrouded rotor, correction of the collective pitch angle is made such that the overall performance matches with experiment to account for the uncertainties of the experimental model configuration. Details of the flow field compare well with the experiment confirming the validity of the present method.

The Linkage between Brand Identity and Brand Image (브랜드 아이덴티티와 브랜드 이미지 관련성 연구 : 특정 제품군 내 브랜드 포지셔닝을 중심으로)

  • Park, Pum-Soon
    • Cartoon and Animation Studies
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    • s.18
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    • pp.89-101
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    • 2010
  • This paper examined the effect of long-term ad campaign for building of brand identity and the relationship between brand identity as a viewpoint of a company and brand image in a viewpoint of consumers. As a result, it was revealed that advertising played an important role to make brand identity. In specific, a long-term ad campaign with a consistent concept and message was more effective for consumers to imbue clear and differential brand traits. In addition, it is discovered that the consistency and durability of advertising message for the advertised brand are contributed to consumers' positive attitude toward the brand. This result was revealed from the comparison of print advertisements for two brands-'Chamisul fresh' and 'Chumchurum', which are alcoholic brands on an intense competition in the same soju market in Korea. While Chumchurum has been consistently focused on one core trait for the brand, Chamisul fresh has been concentrated on multiple brand traits in the advertising campaign for four years since the brand had been launched.

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