• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.153-161
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• 2002

다사용자계층 통행배정(Multiple User Class Assignment) 문제란 교통망을 이용하는 통행자들이 이질적인 통행계층으로 구성된 경우, 이들 각 계층의 통행수요를 교통망에 배정하는 문제를 의미한다. 이는 기존 통행 배정모형들이 모든 통행자의 통행특성이 동질적이라고 가정함으로서 발생하는 불합리한 통행배정 결과를 완화시키기 위한 방법이다. 또한, 최근 지능형교통체계(Intelligent Transportation Systems, ITS)사업에서 교통정보제공시스템이 구현될 예정임에 따라, 교통정보를 제공받는 계층과 그렇지 못한 계층간의 영향을 분석하거나 혼잡통행료부과 등과 같은 교통관리전략을 정확히 평가하기 위해서 다사용자계층 통행배정모형에 대한 관심이 증가하고 있다. 그러나, 다사용자계층 통행배정모형의 경우, 사용자간의 상호영향으로 통행비용함수의 1차 편미분행렬(Jacobian matrix)이 비대칭(Asymmetric)이 되어 동등 수리최소화문제(Equivalency mathematical Minimization program)로 구성할 수 없고 또한 수치적으로 풀기가 어렵다는 문제가 있다. 본 연구는 이런 문제점을 극복할 수 있는 모형식과 알고리듬을 제시코자 한다. 본 연구에서 제시된 모형은 2가지 특징이 있다. 먼저, 각 사용자 계층간의 상호영향을 모형내에 반영하며, 기종점쌍간의 통행시간변화에 따른 수요변화를 고려한다는 점이다. 이를 위하여 변동부등모형(Variational Inequality Model. VI)으로 문제를 구성하며, 이에 대한 해석 알고리듬도 제시한다. 또한, 변동부등모형으로 구축된 다사용자계층 모형이 다사용자계층 균형조건과 동일함을 보여주는 동등성조건(Equivalency condition)도 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10b
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• pp.376-378
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• 2004

리페이싱은 다계층 아키텍처에서 클라이언트가 접하는 표현 계층을 리팩토링하는 것이다 즉 리페이싱은 표현 계층의 부적절한 구조 및 코드를 찾아내어 적절하게 개선하는 작업이다. 리페이싱은 1) 코드 가독성을 향상시키고, 2) 유지보수를 원활하게 하며, 3) 시스템이나 제품의 업그레이드 과정을 도와준다. 이 논문은 리팩토링을 참고하여, 리페이싱 절차를 제안하고, 실제로 카탈로그 중 하나인 '표현 계층과 업무 처리 계층(Business Logic Layer)의 분리' 카탈로그를 소개한다

• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.217-228
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• 2009

In this paper, we consider a multi-class queueing system in which different classes of customers have different arrival rates, service rates and class-transition probabilities. We use the fast simulation method to estimate the overflow probability and the expected number of customers of each class at the first time the total number of customers hits a high level. We also discuss the overflow probabilities and the expected number of customers at different loads, respectively.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.155-167
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• 2008

This paper studies a multiple user class variable demand user equilibrium and system optimal condition, and then establishes solution algorithms for them. The traffic network equilibrium is accomplished with basis on following assumptions. For considering heterogeneous road user, several user classes have discrete set of VOTs and the travel demand of each user classes varies according to generalized travel cost. this paper specifically investigates following question on multi-class variable demand: Are user equilibrium flows pattern dependent on the unit (time or money) perceived by road user classes? What is system optimal condition according to the unit used in measuring the travel cost or disutility? Finally, using this network equilibrium condition, The traffic assignment algorithm of each equilibrium condition are established.

• Convergence Security Journal
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• v.12 no.3
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• pp.35-43
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• 2012

The explosive growth of Internet traffic cause by smart equipment such as smart phone has led to a dramatic increase in demand for data transmission capacity and network control architecture, which requires high transmission rates beyond the conventional transmission capability. Next generation networks are expected to be controlled by Generalized Multi-Protocol Label Switching(GMPLS) protocol suite and operating at multiple switching layers. In order to ensure the most efficient utilization of multilayer network resources, effective global provisioning that providing the network with the possibility of reacting in advance to traffic changes should be provided. In this paper, we proposes a new path selection scheme in multilayer optical networks based on the vertical PCE architecture and a different approach to efficiently exploit multiple PCE cooperation.

• The Transactions of the Korea Information Processing Society
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• v.5 no.1
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• pp.11-23
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• 1998

In very large databases, the problem of searching for interesting information effectively is very important in terms of efficiency and flexibility. A multiple layered database approach based on AOG(attribute-oriented generalization) method is one of the useful approaches for knowledge discovery under various situations. In this paper, we propose a multiple layered database design methodology based on AOG method in object-oriented databases. In addition, we propose a dynamic schema evolution model and implementation strategy in order to continue providing information effectively in multiple layered databases.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.536-545
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• 2021

The purpose of this study was to identify the differences of career barriers of multicultural adolescents by family income class. The study also examined the differences of social contextual factors affecting career barriers. A total of 1,265 cases from the sixth wave of Multicultural Adolescents Panel Study was used for the analysis. The main findings are as follows: First, multicultural adolescents showed significant differences in carrier barriers by income class. Second, low-income class adolescents were significantly affected by lack of mother involvement and academic adjustment, and middle-income class were affected by family support, academic adjustment, peer relationships, and adults helping at school. Study findings were discussed in terms of implications for practical intervention on career barriers of multicultural adolescents.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.408-410
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• 1999

본 논문에서는 PNNI의 복합 노드 표현을 지원하는 다계층 라우팅 알고리듬에 대해서 제안한다. PNNI는 다 계층 방법으로 여러 망을 연결하여 비교적 광범위한 망을 지원할 수 있다. 다계층 형성시 가상 그룹 노드(Logical Group Node)는 하위 피어 그룹(Peer Group)에 대한 묘사를 하게 되며 이를 복합 노드 표현(Complex Node Representation)이라 한다. 복합 노드 표현 정보를 이용한 최단 경로 결정은 매우 어려운 일이다. 이에 복합 노드 표현 정보를 단순 노드 표현(Simple Node Representation)화 하여 보다 쉽고, 정확하며, 보편적으로 적용 가능한 라우팅 방법에 대해서 제안하고자 한다.

• Convergence Security Journal
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• v.13 no.3
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• pp.25-31
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• 2013

Looking at the recent value change of users and the usage pattern of network users, it is changing from simple web information, one-way information acquisition and data transmission to increase of usage of multimedia, increasing demand for security and customization, and increasing demands for free mobility. Due to this change of demand, the services which were provided individually, developed into a form which is merged, the network also seems to develop into the combined network from the individual network for individual service, and the communication network control technology which is the core technology is also rapidly developing. To reflect the users' demands, the next generation network created the multi-layer network which is based on the WDM/IP transmission system and added the to make it easy to restructure. P-OTS (Packet-Optical Transport System) can be defined as a platform that combines SONET/SDH, Ethernet, DWDM, optical transport network (OTN) switching and reconfigurable optical add-drop multiplexers (ROADMs). In this paper, we suggested that the optimum path choice be performed through diversification of the PCE-based path selection using the information of various layers altogether in the multi-layer environment, compared with the established path selection method when the path was selected using the information of each layers.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.4
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• pp.67-75
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• 2009

Multi-layered video coding that provides scalability across the visual content has emerged for easily adaptive service over current heterogeneous network. However, the network is still error prone environment so that video service may suffer packet loss or erroneous decoding of the video. Especially distortion caused by the burst error may propagate to several pictures until intra refreshing, which will raise a terrific degradation of picture quality. To overcome the problem at terminal independently, we propose a new error concealment algorithm for the multi-layered video coding. The proposed method uses the similarity of between layers in the multi-layered video coding and POCS (Projections Onto Convex Sets) which is a powerful error concealment tool, but heavily dependent on initial values. To find adequate initial value which can reduce iteration times as well as achieve high performance, we took consideration into both features of layered approach coding and the correlation in neighbor blocks. The simulation results show that the proposed concealment method works well.