• 한국통신학회논문지
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• 제28권4B호
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• pp.306-315
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• 2003

광통신망에서는 언제 발생할 지 모를 통신경로상의 장애에 대비하여 통신망의 생존성을 확보할 수 있는 장애복구가 중요하다. 본 논문에서는 백업경로 자원을 공유하는 메쉬형태의 광통신망에서 장애시 이를 복구하는 방법에 대해 기존 제안된 방식을 분석하고 이에 대해 자원의 활용성과 관리의 효율성을 높일 수 있는 deferred commit 복구 구조를 제안하였다. 그리고 복구신호의 전달에 필요한 메시지 형태 및 포맷, 전달흐름 등을 구체적으로 제시하였다. 또한 deffered commit 구조에서 소요되는 지연시간을 내용적으로 규명하고 시뮬레이션을 통해 여러 복구 구조들간의 특성을 비교하였다.

• 대한전자공학회논문지TC
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• 제47권11호
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• pp.49-58
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• 2010

본 논문은 메쉬 형태 MPLS 망에서 링크 장애가 동시에 여러 개 발생할 경우에 QoS를 보장하면서 빠르게 세그먼트를 복구하는 방법론을 제시한다. 방법론의 주요 특징은 빠른 세그먼트 복구를 위해 망 resilience와 QoS 요구조건이 함께 고려되었다는 점이다. 메쉬 형태 MPLS 망에 대해 망 resilience를 보장하는 대체 세그먼트의 존재유무를 테스트하기 위한 충분조건을 유도하고, 망 resilience와 QoS 요구조건을 충족시킬 수 있는 대체 세그먼트 생성 알고리즘을 제안한다. 마지막으로, 제안된 세그먼트 복구 알고리즘의 효율성을 시뮬레이션을 통해 보인다.

• Current Optics and Photonics
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• 제8권3호
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• pp.215-224
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• 2024

In medium- and long-range optical imaging systems, atmospheric turbulence causes blurring and distortion of images, resulting in loss of image information. An image-restoration method based on an adaptive feature-fusion multi-input-multi-output (MIMO) dense U-shaped network (Unet) is proposed, to restore a single image degraded by atmospheric turbulence. The network's model is based on the MIMO-Unet framework and incorporates patch-embedding shallow-convolution modules. These modules help in extracting shallow features of images and facilitate the processing of the multi-input dense encoding modules that follow. The combination of these modules improves the model's ability to analyze and extract features effectively. An asymmetric feature-fusion module is utilized to combine encoded features at varying scales, facilitating the feature reconstruction of the subsequent multi-output decoding modules for restoration of turbulence-degraded images. Based on experimental results, the adaptive feature-fusion MIMO dense U-shaped network outperforms traditional restoration methods, CMFNet network models, and standard MIMO-Unet network models, in terms of image-quality restoration. It effectively minimizes geometric deformation and blurring of images.

• 전기학회논문지
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• 제66권10호
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• pp.1460-1465
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• 2017

Outage areas can be transferred to adjacent feeders to restore power supply in case of the fault on the distribution system. Feeders in the small island or mountain area may not have backup feeders due to the low density of load. In this weakly meshed open loop system, BESS can be used as a backup feeder to improve reliability of power supply. This paper proposes a new network reconfiguration method for BESS based service restoration. Fuzzy decision making technique is adopted to deal with fuzziness of service restoration planning rules. Case studies using KEPCO real distribution system have been performed to verify feasibility of the proposed method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.3-5
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• 2001

When a fault occurs on distribution network. blackout region may happen, then it should be restored as fast as possible to minimize interruption of electric service. In this paper. A near optimal method to restore distribution network is proposed. For an optimal restoration, the number or switching operations must be minimized. The proposed method generates a general restoration plan for any distribution network fault and designed to reduce switching operations considering available load transfers. In this method overall process time can reduce with heuristic rules, which make a reduction of search space before restoration process. To achieve a near optimal solution, multiple load transfer algorithm is proposed too.

• 한국환경복원기술학회지
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• 제16권1호
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• pp.245-257
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• 2013

Lately, besides promoting the biodiversity of the natural ecosystems, there is a demand for climate change mitigation features that will reduce greenhouse gases and prevent disasters that will bring damages such as torrential rains. However, there was not a lot of discussion on the soils that are key in these features. Therefore, this paper proposes a network (Gold Network) as an alternative that will solve the problem that was filed earlier by figuring out how to compose the soil environment. First, in order to maximize the ecological status and value of the soil, a soil network can be proposed through the vertical and horizontal connections of the fragmented soil. Second, there is a need to understand and research the organic system of the ecosystems as well as the complex perspective of the ecosystem services, not only the fragmentary perspectives of the soil remediation, planting improvements or the other existing elements. Third, there is a need to apply the integrated perspective of the Landscape Ecology, Ecological Engineering and Restoration Ecology for the connectivity of the soil (network) due to it being in the execution of the soil network. If a soil network was to be built, a fundamental ecological network would be realized to not only promote biodiversity but also to prepare effective adaptation to climate change.

• 한국통신학회논문지
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• 제24권8B호
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• pp.1421-1425
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• 1999

ATM 망에서 노드나 링크에서의 장애발생 시 이를 복구하기 위한 방안에 관하여 연구하였다. 네트워크상의 각 노드들은 RCC(Routing Control Channel)을 이용하여 노드들간의 네트워크 상태 정보를 가진 NSE(Network State Element)를 교환함으로써 각각의 노드들은 네트워크내 자원에 대한 동일한 토폴로지 정보를 가지게 된다. 그러므로, 동적으로 변하는 네트워크 상태를 반영한 새로운 대체 경로를 소스노드에서 설정하는 기법을 제안한다. 이러한 방법을 적용한 결과 호 수락 제어(Connection Admission Control)단계에서의 호 설정(cell setup) 실패율을 크게 줄여 복구의 향상 및 메시지 수의 축소 그리고 트래픽을 감소시키면서 빠른 복구가 가능하였다.

• 한국환경복원기술학회지
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• 제22권6호
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• pp.97-114
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• 2019

This study aims to analyze the effect of urban ecosystem restoration projects by evaluating the short-term restoration performance of the project sites, from both qualitative and quantitative evaluations. In this study, for the qualitative evaluation, we derived the evaluation frame from previous studies and literature. For the quantitative evaluation, the changes in ecological connectivity after the restoration project were described using landscape permeability and network analysis. In addition, changes in habitat quality after the restoration project were evaluated by using InVEST Habitat Quality Model. These evaluations were applied to the three natural madang (ecological restoration) projects and two ecosystem conservation cooperation projects. As a result, three categories, 10 indicators, and 13 sub-indicators were derived from literature as the evaluation frame for this study. In the case of quantitative evaluation of restoration performance, habitat quality increased by 45% and ecological connectivity by 37% in natural-madang, and habitat quality by about 12% and ecological connectivity by about 19% in ecosystem conservation cooperation projects. This implies that the ecological restoration project can increase the ecological connectivity and the habitat quality of degraded sites even in a short period of time by improving the land-cover and land use. The results by applying the evaluation frame indicated that ecological and environmental factors and the ecological functions were improved by the restoration works, even though the magnitude of performances were diverse depending on the specific evaluation items, project type, and site characteristics. This study clarified that the success of ecological restoration project should be assessed by both of the short-term and long-term goals, which can be achieved by the maintenance and sustainable management, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.192-194
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• 2005

Power system restoration following a massive blackout starts with reenergizing of primary transmission lines. This paper presents the restoration and training system for Jeju network using RTDS. System operators can simulate the jeju restorative procedures from primary transmission lines to ail the system topology written by KPX in the real time. Owing to the efficient restoration training by the system, It is expected to restore the power system rapidly and accurately when a massive blackout occurs, and also the system helps student understand the restoration method.

• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.125-131
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• 2005

Service restoration is one of the most important missions in distribution system operation. This paper proposes a multi-agent system approach to distribution system restoration. Every relay is developed as an agent by adding its own intelligent, self-tuning and communication ability. The relay agent independently calculates and corrects its restoration index through communication with neighboring agents and its own intelligence. The proposed algorithm is applied to a simple network to demonstrate its soundness and effectiveness.