• Title/Summary/Keyword: Protection area

Search Result 1,917, Processing Time 0.026 seconds

Influences of Coatings and Solution Corrosivity on Cathodic Protection of Metallic Materials

  • Yoo, Y.R.;Chang, H.Y.;Jin, T.E.;Kim, Y.S.
    • Corrosion Science and Technology
    • /
    • v.5 no.3
    • /
    • pp.106-111
    • /
    • 2006
  • Painting has protected metallic stack but the paint films may be degraded and corrosion problem can be arisen. To protect the painted metal stack, cathodic protection can be applied. If cathodic protection is applied to bare metal, only small area may be protected. However, if cathodic protection is applied to painted metal surface, large area can be protected and the lifetime of paint films can be extended. High corrosion resistant alloys were corroded at a Flue Gas Desulfurization (FGD) facility of power plant within a short period and thus cathodic protection can be used to protect these metals. On the base of computer simulation, if cathodic protection is applied to bare metal in a FGD environment, it was estimated that applied current could almost be spent to protect area near the anode. However, if cathodic protection is applied to high resistant-coated metal, the much larger area from the anode could be effectively protected.

A Study on determining Flood Protection Elevation in Urban Area (도시지역 방어침수위 설정에 관한 연구)

  • Shin, Sang-Young;Lee, Yang-Jae
    • 한국방재학회:학술대회논문집
    • /
    • 2008.02a
    • /
    • pp.649-652
    • /
    • 2008
  • In urban area, flood risk is getting higher because of inland flood risk has grown up by changing rainfall intensity, rainfall pattern, changing land use and so on. Urban area is needed higher flood protection level to protect accumulated people, buildings and other infrastructures. However, even though former flood protection has focused on overflow from river, there is not a guide line for evaluating proper flood protection level. Thus, it is necessary to protect flood from inland flooding as well as overflow from river and need a proper method to evaluating flood protection level. This study present a method of determining flood protection elevation by using GIS tools for deciding proper flood protection level. The study result may contribute to urban flood protection measures in which inland flood risk increases.

  • PDF

Comparative Analysis of Regulations for Consumer Protection of Local Self-government (지방소비자행정 발전을 위한 광역자치단체의 소비자보호조례와 소비자정책심의위원회 운영 현황 비교분석)

  • 송인숙;제미경
    • Journal of the Korean Home Economics Association
    • /
    • v.40 no.9
    • /
    • pp.79-95
    • /
    • 2002
  • In this paper the consumer protection regulations of 16 wide area self-governments in Korea are studied. Status of consumer protection policy committees and their general policies for consumer protection of these wide area self-governments are also investigated. The data of consumer protection regulation were collected from the internet web-site of each self-government and the status of consumer protection policy committee and the general policy for consumer protection were obtained by requesting each self-government to report administration information during May through October in 200l. 13 of 16 wide area self-governments except Daegu, Inchon, and Jejudo have own consumer protection regulations. Major parts of these regulations conform the standard regulation of ministry of Government Administration and Home Affairs. Many of the consumer protection policy committees reported that they do not have meetings constantly. Moreover since the price of goods and services is the typical subject of meetings, the committees do not seem to properly play the role of a consumer protection policy authority. Contents of the general policy for consumer protection of many self-governments are simple description of detailed practicing plans according to the general consumer protection policy of the national government. By criticizing the problems aroused during the study of consumer protection policy of self-governments, suggestions are given which will help for the development of consumer policy of wide area self-governments.

Development of the digital protection relay which displays the trip area in real time (실시간 사고영역을 표현하는 디지털 보호계전기 개발)

  • Cho, Chul-Hee;Lee, Byeong-Ho;Kim, Yoon-Hoe
    • Proceedings of the KIEE Conference
    • /
    • 2007.07a
    • /
    • pp.499-500
    • /
    • 2007
  • The existing digital protection relay is continuously growing with an improvement in technology. In this paper, we propose the development of the digital protection relay which displays the trip area in real time. In most of the digital protection relays monitor whether analog signal enters into the pre-determined trip area, but those aren't provide the trip area information for a operator in real time. Therefore, if the digital protection relay continuously displays the trip area in real time, the operator analysis power system status easily. This paper particularly introduces selective ground protective relay and differential protective relay with trip area and presents a method of providing the trip area information to operator in real time.

  • PDF

A Method for Zoning the Parcel-based Protecting Area of the Ecological Network in Forest (지적 기반 산림생태네트워크 보호구역 설정방안)

  • Jang, Rai-Ik;Jang, Gab-Sue;Jung, Ok-Sik;Ra, Jung-Hwa
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.12 no.6
    • /
    • pp.131-142
    • /
    • 2009
  • The purpose of this study is to detect the protection area around the Geum-buk and Geum-nam Mountains for making a sustainable ecological network. The protection area in the Geum-buk and Geum-nam Mountains was analyzed by using spatial data and a field survey for landscape conservation purposes. A survey scope was fixed using digital elevation model, and the protection area was finally determined based on the parcel map called as the Korea Land Information System (KLIS). Here we have several conclusions in this study. First, spatial data used in this study were a map of ecological and natural degree (MEND), forest distribution map, elevation map, slope map, and several maps for the protection area assigned by laws regarding to the natural resources. Second, we used 4 alternatives to determine the best choice for showing the ecological network in the study area. One alternative (alt. 3) of 4 ones was finally chosen as the best condition for making the ecological network. The condition in elevation and slope was a little modified to a lower level in alt, 3. The result derived from alt, 3 reflected the continuity and connectivity in the ecological network and we estimate that the protection area can protect the core area using the buffer zone around the ecological network. Finally the parcel-based protection area in the Geum-buk and Geum-nam Mountains had $493.92km^2$ of the core area, and $233.99km^2$ of the buffer zone, which means the parcel-based protection area increased by $97.76km^2$ in the core area, but decreased by $76.61km^2$ as of in the topographical map.

Development of Dynamic Frequency Monitoring Software for Wide-Area Protection Relaying Intelligence (광역 보호계전 지능화를 위한 동적 주파수 모니터링 S/W 개발)

  • Kim, Yoon-Sang;Park, Chul-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.61 no.4
    • /
    • pp.174-179
    • /
    • 2012
  • The social and economic level of damages might be highly increased in the case of wide-area black-outages, because of heavy dependence of electricity. Therefore, the development of a wide-area protection relay intelligence techniques is required to prevent massive power outages and minimize the impact strength at failure. The frequency monitoring and prediction for wide-area protection relaying intelligence has been considered as an important technology. In this paper, a network-based frequency monitoring system developed for wide-area protection relay intelligence is presented. In addition, conventional techniques for frequency estimation are compared, and a method for advanced frequency estimation and measurement to improve the precision is proposed. Finally, an integrated monitoring system called K-FNET(Korea-Frequency Monitoring Network) is implemented based on the GPS and various energy monitoring cases are studied.

Improved Coordination Method for Back-up Protection Schemes Based on IEC 61850 (IEC 61850 기반 후비보호계전시스템 보호협조 개선방안)

  • Kim, Hyung-Kyu;Kang, Sang-Hee
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.1
    • /
    • pp.43-49
    • /
    • 2011
  • A distance relay scheme is commonly used for backup protection. This scheme, called a step distance protection, is comprised of 3 steps for graded zones having different operating time. As for the conventional step distance protection scheme, Zone 2 can exceed the ordinary coverage excessively in case of a transformer protection relay especially. In this case, there can be overlapped protection area from a backup protection relay and, therefore, malfunctions can occur when any fault occurs in the overlapped protection area. Distance relays and overcurrent relays are used for backup protection generally, and both relays have normally this problem, the maloperation, caused by a fault in the overlapped protection area. Corresponding to an IEEE standard, this problem can be solved with the modification of the operating time. On the other hand, in Korea, zones are modified to cope with this problem in some specific conditions. These two methods may not be obvious to handle this problem correctly because these methods, modifying the common rules, can cause another coordination problem. To overcome this problem clearly, this paper describes an improved backup protection coordination scheme using an IEC 61850-based distance relay for transformer backup protection. IEC 61850-based IED(Intelligent Electronic Device) and the network system based on the kernel 2.6 LINUX are realized to verify the proposed method. And laboratory tests to estimate the communication time show that the proposed coordination method is reliable enough for the improved backup protection scheme.

Current Status of the Ecosystem at the Nakdong River Estuary and Management Plan (낙동강하구의 생태계 현황과 관리방안)

  • Sangwook Han;Kwangjin Cho;Pyoungbeom Kim;Haeseon Shin
    • Journal of Environmental Science International
    • /
    • v.32 no.12
    • /
    • pp.943-953
    • /
    • 2023
  • This study analyzed the ecological characteristics of the wetland protection area at tthe Nakdong River through vegetation and biota surveys, which showed that brackish water meets fresh water, a unique ecological environment has been created, biodiversity is high, and diverse habitats are distributed. Eleven plant communities, including four woody communities and seven grass communities, are distributed along the coast, and a total of 514 species, including 11 endangered wildlife species, were identified in terms of species diversity. Among them, the species diversity of the Eulsuk-do area was found to be relatively higher than that of other Barreir Islands areas. The presence of a population of Sterna albifrons on Sinja-do and a population of Eremias argus on Jinwo-do, an area outside the boundaries of the wetland protection area, confirmed the conservation value of the wetlands and the need to expand the boundaries of the wetland protection area. It is judged that this information can be used as basic information for a systematic conservation and management plan for the wetland protection area at the Nakdong River Estuary and as basic data to support the establishment of a policy.

Effects of Special Protection Area Designation on Soil Properties and Vegetation Coverage of Degraded Trails (국립공원 특별보호구 지정이 훼손 탐방로 주변 토양과 식생피도에 미치는 영향)

  • Kim, Dong-Hwan;Lee, Dong-Ho;Kim, Hyun Seok;Kim, Seong-il
    • Journal of Korean Society of Forest Science
    • /
    • v.104 no.3
    • /
    • pp.352-359
    • /
    • 2015
  • This study was conducted to evaluate how the special protection area designations of degraded trails effect on the soil and vegetation recovery of degraded trails. The study areas were established on an opened trail and a 16-year closed trail, which was prohibited to enter after the designation as a special protection area for recovery, at Bukhansan National Park. Soil core sampling and measurements of vegetation cover were performed to compare soil and vegetation properties of the trails. Soil bulk density increased and soil water total nitrogen decreased on the opened trail, while no significant differences were found on bulk density, soil water, total nitrogen, acidity, and organic matter on the closed trail. On the opened trail, vegetation cover was seemed to be degraded, because vegetation litter cover ratio was low and barren rock cover ratio was high. On the closed trail, litter rock barren cover ratio of the closed trail was recovered, but only limited recovery was found on vegetation cover by applying environmental damage condition rating class. In conclusion, the closed trail was recovered by designation of special protection area, while difference in recovery progress of soil and vegetation was found. Therefore, designation of special protection area of degraded area should be based on scientific basis of recovery characteristics of the area. In order to improve the effectiveness of special protection area system, further specific standards for special protection area designation and management would be needed, considering ecological and social importance of target areas.

A Novel Online Multi-section Weighed Fault Matching and Detecting Algorithm Based on Wide-area Information

  • Tong, Xiaoyang;Lian, Wenchao;Wang, Hongbin
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.6
    • /
    • pp.2118-2126
    • /
    • 2017
  • The large-scale power system blackouts have indicated that conventional protection relays that based on local signals cannot fit for modern power grids with complicated setting or heavily loaded-flow transfer. In order to accurately detect various faulted lines and improve the fault-tolerance of wide-area protection, a novel multi-section weighed fault matching and detecting algorithm is proposed. The real protection vector (RPV) and expected section protection vectors (ESPVs) for five fault sections are constructed respectively. The function of multi-section weighed fault matching is established to calculate the section fault matching degrees between RPV and five ESPVs. Then the fault degree of protected line based on five section fault degrees can be obtained. Two fault detecting criterions are given to support the higher accuracy rate of detecting fault. With the enumerating method, the simulation tests illustrate the correctness and fault-tolerance of proposed algorithm. It can reach the target of 100% accuracy rate under 5 bits error of wide-area protections. The influence factors of fault-tolerance are analyzed, which include the choosing of wide-area protections, as well as the topological structures of power grid and fault threshold.