• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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• pp.371-374
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• 2001

The upstream noise level was measured and analysed for the sample HFC networks to HFC subscriber capacity in the HFC network that is only for cable modem services. The upstream bands were measured not only in HFC networks that have accommodated only cable modem subscribers but in CATV networks that have accommodated cable modem and CATV subscribers. The study says that C/N of HFC networks be maintained though the networks have more cable modem subscribers than CATV networks do. This results are being expected to be used as a basis of network design and management of HFC network provider .

• Journal of Communications and Networks
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• 제8권4호
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• pp.432-441
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• 2006

As the community antenna television (CATV) networks becomes ubiquitous, instead of constructing an entirely new broadband network infrastructure, it has emerged as one of the rapid and economic technologies to interconnecting heterogeneous network to provide broadband access to subscribers. How to support ubiquitous real-time multimedia applications, especially in a heavy traffic environment, becomes a critical issue in modern CATV networks. In this paper, we propose a time guaranteed and efficient upstream minislots allocation algorithm for supporting quality-of-service (QoS) traffic over data over cable service interface specification (DOCSIS) CATV networks to fulfill the needs of realtime interactive services, such as video telephony, video on demand (VOD), distance learning, and so on. The proposed adaptive fast expansion algorithm and the loading statistics with dynamic swapping algorithm have been shown to perform better than that of the multimedia cable network system (MCNS) DOCSIS.

• 항공우주시스템공학회지
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• 제16권4호
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• pp.68-76
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• 2022

본 논문에서는 기하학적 특성을 고려한 케이블 네트 형상설계 방법론을 제시하고, 트러스 링 그리고 케이블 네트의 구조 유연도를 고려한 반사판 안테나의 케이블 네트워크 형상 실효성을 검증한다. 기하학적 비선형성을 고려한 케이블 네트의 유한요소 모델을 개발한다. 경계조건의 하중에 따른 형상변형 해석을 통하여, 케이블 네트의 형상 설계변수 특성을 제시 한다. 프레임 요소를 이용하여 전개형 트러스 링 구조를 모델링하고 정적 하중 해석을 수행한다. 전개된 링 구조에 가해지는 장력에 의해 케이블 네트 반사판은 정확한 형상을 유지하게 된다. 가해지는 장력, 케이블 네트 그리고 트러스 링 구조의 유연도를 고려하여, 케이블 네트워크 형상설계에 반영하고 최종 형상을 제시한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.558-562
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• 2003

In this paper, neural networks is studied to apply as a PD source classification in XLPE power cable specimen. For treeing discharge sources in the specimen, three defected models are made. And these data making use of a computer-aided discharge analyser, statistical and other discharge parameters is calculated to discrimination between different models of discharge sources. And also these parameter is applied to classify PD sources by neural networks. Neural Networks has good recognition rate for three PD sources.

• 전산구조공학
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• 제11권1호
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• pp.179-190
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• 1998

두개의 케이블요소를 이용한 3차원 케이블망의 정적 비선형 유한요소해석기법을 제시한다. 먼저, 공간 트러스요소와 탄성현수선 케이블요소(elastic catenary cable element)의 접선강도행렬과 질량행렬을 유도하는 과정을 간략히 요약한다. 지점 변위를 일으키고 자중을 받는 케이블망의 초기평형 상태를 결정하기 위하여, Newton-Raphson 반복법에 근거한 하중증분법과 현수케이블요소를 적용하는 경우에 viscous damping을 고려한 dynamic relaxation법을 제시한다. 또한 초기의 정적평형상태를 기준으로 추가하중에 대한 케이블망의 정적 비선형해석을 수행한다. 지점변위와 외력을 받는 케이블 구조에 대하여 비선형해석을 수행하고, 해석결과들을 기존의 문헌의 결과와 비교, 검토하므로써 본 논문에서 제시한 이론 및 해석방법의 타당성을 입증한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.680-682
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• 1996

Korea Distribution Automation System(KODAS) has been designed and implemented for feeder automation using the paircable as communication media. And we bave been developed the telemetering system using the low voltage line. Kepco have been constructed approximately 60% of the Cable TV(CATV) networks in large city in Korea since 1995, so we have been researching the feeder automation based on CATV networks also. We will contruct the system using its in the area with of cable-TV networks and paircable line in the other area for communication media in future.

• Smart Structures and Systems
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• 제5권4호
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• pp.369-379
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• 2009

The sudden collapse of Interstate 35 Bridge in Minneapolis gave a wake-up call to US municipalities to re-evaluate aging bridges. In this situation, structural health monitoring (SHM) technology can provide the essential help needed for monitoring and maintaining the nation's infrastructure. Monitoring long span bridges such as cable-stayed bridges effectively requires the use of a large number of sensors. In this article, we introduce a probabilistic approach to identify optimal locations of sensors to enhance damage detection. Probability distribution functions are established using an artificial neural network trained using a priori knowledge of damage locations. The optimal number of sensors is identified using multi-objective optimization that simultaneously considers information entropy and sensor cost-objective functions. Luling Bridge, a cable-stayed bridge over the Mississippi River, is selected as a case study to demonstrate the efficiency of the proposed approach.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권2호
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• pp.547-566
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• 2014

This study investigates the decisive factors affecting the survival or collapse of cable networks in the Korean paid broadcasting market from 1993 to 2010. The effects of performance variables discussed in previous studies were verified through survival analyses. According to the results, the most influential factors in the survival of cable networks were horizontal integration (MPP), channel genre, the scheduling of HDTV content, and the proportion of access program scheduling. These findings imply that the differentiation strategy of content suppliers is the most decisive factor among all business performance-related factors. Specifically, the content supply power and strategy of the program provider (PP) have the greatest influence on cable network viability. The present study is meaningful as the first attempt to establish the performance of PPs in Korean pay broadcasting markets through the viewpoint of organizational mortality. Accordingly, the present study can supplement the results of cross-sectional studies conducted with smaller samples.

• 한국전기전자재료학회논문지
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• 제17권8호
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• pp.898-903
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• 2004

In this paper, neural networks is studied to apply as a PD source classification in XLPE power cable specimen. For treeing discharge sources in the specimen, three defected models are made. And these data making use of a computer-aided discharge analyser, statistical and other discharge parameters is calculated to discrimination between different models of discharge sources. And also these parameter is applied to classify PD sources by neural networks. Neural Networks has good recognition rate for three PD sources.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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• pp.134-141
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• 1997

A geometrically non-linear finite element formulation of spatial cable networks is presented using three cable elements. Firstly, derivation procedures of tangent stiffness and mass matrices for the space truss element and the elastic catenary cable element, and the isoparametric cable element are summarized. The load incremental method based on Newton-Raphson iteration method and the dynamic relaxation method are presented in order to determine the initial static state of cable nets subjected to self-weights and support motions. Furthermore, static non-linear analysis of cable structures under additional live loads are performed based on the initial configuration. Challenging example problems are presented and discussed in order to demonstrate the feasibility of the present finite element method and investigate static non-linear behaviors of cable nets.