• Title/Summary/Keyword: Protection and Restoration

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The development study on the power system operation and protection scheme in Myanmar (미얀마 전력계통 운영 및 보호시스템 구축 사업)

  • Kim, Jong-Hwa;Choi, Young-Sung;Han, Seong-Min;Lee, Duck-Jae
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.34-35
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    • 2008
  • KEPCO conducted a third project in Myanmar regarding system operation and protection scheme. This paper deals with blackout reduction plan, reactive power compensation plan and system restoration procedures in operations parts. Moreover protection system improvement plan and standard protection schemes were suggested.

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A Study on the Plan of Plant State for Improvement of Stream-ecosystem - in Case of Chungrang Stream (자연형 하천 생태계를 위한 식생개선 방안 연구 -중랑천을 사례로)

  • Ann, Geun-Young;Lee, Eun-Heui
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.2
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    • pp.35-46
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    • 2000
  • Environmental pollution has become more and more serious in urban areas since industrialization as most streams and rivers were developed heavily because of economic opportunism. Recently river restoration techniques, applied in advanced countries, have been introduced to Korea. But the application of river restoration techniques developed in advanced countries, has a lot of limitations in respect of economic loss during construction, suitability for the domestic situation and the problem of flood control. The method of minimizing the problems must take into consideration these issues, including economic considerations. So from these points of view this study intends to plan ecological river restoration and to create a nature friendly river in the case of the Chungrang river. The subject site is the upper part of Chungrang river, from the Nokchun bridge to Sang-kye bridge, where the ecosystem is well preserved in comparison with other parts of the river. The subject site is divided into 10 sections for plant state investigation. The result of plant-state investigation showed pioneer water plants such as Persicaria thunbergii, Oenanthe jaranica, Rumex crispus. appeared very often. On the basis of the existing plant state, this study has planned an appropriate plant state for the river and has planned for bank protection using a method of construction, which is suitable for natural river. In this study, first of all, it is intended to investigate the plant growth state of Chungrang river and try to plan a particular ecosystem for the river for the purpose of the revival of the natural river.

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Restoration after endodontic treatment with Endocrown (임상가를 위한 특집 3 - Endocrown을 이용한 근관치료 후 수복)

  • Park, Jeong-Kil
    • The Journal of the Korean dental association
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    • v.50 no.7
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    • pp.384-393
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    • 2012
  • Successful treatment of a badly broken down tooth with pulpal disease depends not only on good endodontic therapy, but also on good prosthetic reconstruction of the tooth after endodontic therapy is completed. The ideal treatment of endodontically treated teeth has been widely and controversially discussed. Endocrown is a restorative option for endodontically treated teeth. Endocrown design incorporates the core and short post into the crown as a single restoration. The preparation of endocrown consists of a circular equigingival butt-joint margin and central retention cavity of the entire pulp chamber instead of employing intraradicular posts. This design significantly increases the surface area of the preparation available for cementation. It is particularly useful in young patient teeth for long-term provisional restoration and in teeth with short clinical crowns. This technique represents a promising and conservative method for the treatment of endodontically treated teeth that require long-term protection and stability. Endocrown can be considered as a feasible alternative to full crowns or composite overlays for the restoration of non vital teeth.

Traditional Agricultural Landscape as ail Important Model of Ecological Restoration in Japan

  • Toshihiko, Nakamura
    • The Korean Journal of Ecology
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    • v.25 no.1
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    • pp.19-24
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    • 2002
  • The traditional Japanese agricultural landscape, In which a set of varied land-use patches functions as a sustainable ecosystem landscape unit, not only provides the local people tilth a stable food supply, but also offers a variety of habitats to many species of wildlife. Therefore, remaining natural habitats including those in the traditional agricultural landscape should be maintained whenever possible. In addition, restoration work should be implemented in areas where the natural habitat has been destroyed or severely degraded by human activities. This basic approach to the natural environment is a combination of maintenance and restoration. Types of maintenance and restoration can be classified into three categories according to the countermeasures employed: preservation, conservation and protection types of maintenance, and improvement, reconstruction and creation types of restoration. Four steps are proposed for ecological restoration and maintenance of a target area: exploration, diagnosis, prescription and care. In this process, a model for approaching the goal is important. One of the most important models should center on the traditional agricultural landscape involving a sustainable farming ecosystem. It is necessary to protect traditional landscapes and ecosystems from the degrading impact of urbanization and industrialization, as well as to enhance efforts at restoration.

Vegetation survey in nature-friendly small streams for each protection method (자연형 소하천의 호안공법별 식생분포 조사)

  • Lee, Kang-Suk;Park, Jin-Ki;Yeon, Gyu-Bang;Park, Jong-Hwa
    • Korean Journal of Agricultural Science
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    • v.38 no.2
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    • pp.315-324
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    • 2011
  • Riparian vegetation distribution patterns and diversity relative to various fluvial geomorphic channel patterns, stream bank stabilization methods, and stream flow processes are described and interpreted for selected nature-friendly small stream bank protection of Goesan, central Korea. Idong Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods which was nature-friendly stream bank protection. The project aim to maintain or increase stream bank stabilization ecosystem goods and services while protecting downstream and stream bank ecosystem. A number of protecting methods which were a Flight of fieldstone, Vegetation block, Green river block, Stone net, Green environment block, Eco friendly cobble, Vegetation mat and Geo-green cell and Firefly block were applied on the bank of Idong stream. The stream sites have been monitored about vegetation conditions each method in 2007. We selected six points to separately investigate in left and right bank. The main purpose of this study was to find out suitable methods and to improve stream restoration techniques for ecosystem. On the stream bank, H environment block method (9.7) was the highest average of vegetation coverage and Firefly block method (3.87) was the lowest average in applied methods.

Variable Aggregation in the ILP Design of WDM Networks with Dedicated Protection

  • Tornatore, Massimo;Maier, Guido;Pattavina, Achille
    • Journal of Communications and Networks
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    • v.9 no.4
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    • pp.419-427
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    • 2007
  • In wavelength-division-multiplexing(WDM) networks a link failure may cause the failure of several high-bit-rate optical channels, thereby leading to large data loss. Recently, various protection and restoration mechanisms have been proposed to efficiently deal with this problem in mesh networks. Among them, dedicated path protection(DPP) is a promising candidate because of its ultra-fast restoration time and robustness. In this work we investigate the issue of planning and optimization of WDM networks with DPP. Integer linear programming(ILP), in particular, is one of the most common exact method to solve the design optimization problem for protected WDM networks. Traditional ILP formalizations to solve this problem rely on the classical flow or route formulation approaches, but both these approaches suffer from a excessively high computational burden. In this paper, we present a variable-aggregation method that has the ability of significantly reducing the complexity of the traditional flow formulation. We compare also the computational burden of flow formulation with variable aggregation both with the classical flow and route formulations. The comparison is carried out by applying the three alternative methods to the optimization of two case-study networks.

Mistakes Made, Lessons Learned: The Eulsukdo Wetland Restoration Program

  • Lineman, Maurice J.M.;Do, Yuno;Kim, Ji-Yoon;Joo, Gea-Jae
    • Journal of Environmental Science International
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    • v.23 no.8
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    • pp.1523-1536
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    • 2014
  • Restoration is the process of reducing or reversing damage to an ecosystem so that it can function in its original manner. However, many restoration programs do not achieve this. In the Nakdong Estuary, the largest migratory nesting site in the center of the East Asian-Australasian flyway, an estuarine barrage was constructed in the 1980s that required site restoration following its completion in 1987 and the expansion of several large industrial complexes(Noksan and Jangrim) and a residential development(Myeongji). The goal of the restoration was to restore the function of the wetland to its pre-disturbance state. To achieve this, a restoration program was designed consisting of three stages. The first stage(1993-1995), saw the construction of three artificial wetlands(Shinhori, Daemadeung, and Eulsuk), the second(2003-2005) involved the dredging and returning of farmed lands to their natural state, and the third(2008-2012) focused on the rehabilitation and vegetation development of the wetlands. However, the project has not achieved all of the desired goals, and it is an example of the lapses in ecological restoration following anthropogenic disturbance. Issues that resulted in an incomplete restoration included the timing of the stages, noncompliance with the restoration plan, not directly monitoring the restoration or continuing the monitoring following completion of the development project, and the political subversion of the restoration plan. For the success of the restoration plan, it is necessary to avoid mistakes such as inconsistent monitoring, unequal levels of stakeholder involvement, and political interference.