• Title/Summary/Keyword: Maintenance and Repair

Search Result 1,061, Processing Time 0.032 seconds

Study on the Jurisdiction of the National Technical Qualification (국가기술자격 관할영역에 관한 연구)

  • Park, Jong-Sung;Kim, Hyun-Soo;Kim, Deog-Ki;Lee, Young-Ran
    • Journal of Engineering Education Research
    • /
    • v.12 no.2
    • /
    • pp.24-35
    • /
    • 2009
  • This study was conducted to establish a principle on the fields of National Technical Qualification(NTQ), and aimed at developing criteria on requirements of the qualification that will be managed as the national technical qualification. In order to achieve the objective of the study, we examined the directions of setting the Jurisdiction of national technical qualification through role assignment between the state and private sectors. Also, we reviewed related documents, conducted Delphi survey, consulted the expert group and had an interview session for this study. There are five criteria of the jurisdiction of NTQ presented as follows. First is the field which disturbs social orders or has possibility of harming the good public morals; second, the field that requires high standards of ethics or is directly linked to life, health and safety of the public; third, the field which requires national attention for training of manpower as it is an area that is difficult for private sector to approach or it requires national management; fourth, the field which requires repair or maintenance of resources of traditional culture but is difficult for the private sector to have an access to and fifth, the field where it needs to protect the interest of the nation in the inter-nation relationships. The concrete and detailed standard on the five criteria is also presented in the study.

Evaluation of Beam Behavior with External Bonded L-type GFRP Plate through bending Test (L형 GFRP 외부부착 보강된 보의 휨 실험을 통한 보강 거동분석)

  • Jeong, Yeong-Seok;Kwon, Min-Ho;Kim, Jin-Sup;Nam, Gwang-sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.11
    • /
    • pp.86-93
    • /
    • 2020
  • The demand for maintenance in Korea infrastructure facilities constructed since the 1970s has increased significantly compared to the demand for new construction. Moreover, after the Gyeongju and Pohang earthquakes, seismic performance evaluation, repair, and retrofitting projects have been carried out. Therefore, in this study, a specimen was designed following the L-type GFRP Plate Externally Bonded Retrofit method, one among other retrofit methods. The L-type GFRP Plate was bonded to the specimen by epoxy and a washered steel nail. A four-point bending test was performed to confirm the strengthening effect of the Externally Bonded Retrofit method using an L-type GFRP Plate. The strengthening effect of the L-type GFRP plate was proven experimentally, and the behavior of the beam designed following the L-type GFRP Plate Externally Bonded Retrofit method was evaluated according to Korea's "Design Manual & Specification for Strengthening of RC Structures by Advanced Composites System". Furthermore, the effectiveness of the bonding method, a combination of epoxy and washered steel nail, was also checked. The results showed that the design, according to the guidelines mentioned above, predicted the strength of the member well, but the failure mode did not satisfy the design assumption because of unexpected damage to the GFRP plate due to the fixing method, washered steel nail.

Standardization of the Lease Fee Assessment System of Busan Port Container Terminals (부산항 컨테이너부두 임대료 산정체계 표준화 방안)

  • Kil, Kwang-Soo
    • Journal of Korea Port Economic Association
    • /
    • v.27 no.3
    • /
    • pp.65-90
    • /
    • 2011
  • Private stevedoring companies are leasing and operating the container terminals of the Busan Port. The total amount of lease fees private stevedoring companies paid in 2010 reached 161 billion wons, an approximately 66 percent of the total revenue of the Busan Port Authority(BPA). In other words, lease fees are the most important revenue source for BPA. However, the lease fee assessment system of Busan container terminals goes against the principle of equity due to different assessment methods and criteria adopted by each container terminal. Therefore, the purpose of the study is to analyze the systematic problems of the lease fee assessment system that is used at Busan container terminals, and propose a new standardized scheme with a case study on the new system. In order to standardize the assessment system, the assessment methods need to be simplified by using the Discounted Cash Flow(DCF) method. In addition, the assessment criteria such as assessment duration, discount rates, price indexes, estimated container throughputs, sales unit price per TEU, operation costs, including labor costs, need to be standardized as well. The new standardized assessment system can be applied to estimate lease fees for new terminals. However, for existing terminals to run the new system, factors such as assessment duration, discount rates, price indexes, estimated container throughputs, investment and re-investment costs, and maintenance & repair costs of the new system should be changed slightly.

A Case Study of the CR based e-Marketplace Implementation in Nuclear Parts Company (CR 기반의 원전부품제조업체 e-Marketplace 구현)

  • Jung, Lee-Sang;Ha, Chang-Seung;Lee, Seok-Yong
    • Journal of the Korea Society of Computer and Information
    • /
    • v.14 no.8
    • /
    • pp.145-152
    • /
    • 2009
  • Manufacturer's competitiveness in the MRO industry, which is to stimulate the growth of the business-to-business e-commerce market, has recently become more important. A nuclear parts manufacturer was supplying products based on irregular demand from clients which differs from ordinary MRO business practices. The reason for this is the Nuclear Parts Manufacturer has fallen behind the e-commerce performance of other industries, and they lack global competitiveness due to the low efficiency of the individual companies within it. In this study, we developed an MRO based a-Marketplace system to minimize repetitive ordering of raw materials, lack of reusability and inefficiency of transaction processing which was a result of the former legacy business practice, In order to accomplish the purpose of this study, we implemented a web based automated CR system which considered the characteristics of the nuclear parts manufacturing: the system has sub modules such as ordering, product management, transaction management, warehousing and raw material handling. As a consequence of the system implementation, H corporate successfully automated ordering of raw materials, quotation processing and inventory management compared to the legacy business process, achieving increased efficiency by reducing wasteful resources.

A Study on the Unified Operation and Maintenance System of Irrigation Facilities in Korea - With Reference to the Survey Results on the Activities of Irrigation Fraternities in Chungnam Province - (농업용수리시설의 유지관리체제일원화에 관한 연구 - 충남지역 수리계 운영실태조사결과를 중심으로 -)

  • Kim, Sung-Min;Lim, Jae-Hwan
    • Korean Journal of Agricultural Science
    • /
    • v.31 no.1
    • /
    • pp.53-75
    • /
    • 2004
  • This study is aimed at identifying the national economic value of the irrigation facilities by reviewing the existing papers on economic values of the irrigation facilities and presenting current status of dual O & M problems of the irrigation facilities. This study suggested the unified O & M system rather than continuing the existing dual O & M system of irrigation facilities based on the surveyed results of the activities of irrigation fraternities in Chungnam Province. The findings and proposals for the successful unified and mono O & M system of the irrigation facilities are as follows: (1) Total number of irrigation facilities in the nation accounts for 67,582, while the total length of irrigation and drainage canals amounted to about 174,259km. On account of the total length of structural canals was estimated at 31%, much losses of water and much O & M costs have been inevitable for the full irrigation rice culture. In spite of the past heavy investment for irrigation facilities, the ratio of rain-fed and partially irrigated paddy fields accounts for 23% in 2003. Both Korea Agricultural and Rural Infrastructure Corporation (KARICO) and the city and Gun Governments have managed the irrigation facilities separately by irrigation fraternities. The KARICO have commanded 59% of irrigation paddy area with 18% of the total irrigation facilities, while the city and Gun governments covered 41% of irrigation paddy area with 82% of the existing number of irrigation facilities representing small and medium scale. (2) The 1999 demand prices of irrigation water per ton expressed in 2000 constant market price was estimated at 388 won, the supply price was amounted to 184 won per ton. Considering the supply and demand curve of the irrigation water, the existing irrigation facilities could not satisfy the demand of irrigation water. (3) In 1999, total present added value of the irrigation facilities during the economic life accounted for 48 trillion won, while total supply cost was 44.7 trillion won. The marginal benefit and cost ratio of irrigation water was 1.08. (4) The total O & M cost per year amounting to 681.1 billion won have been required to maintain and repair the existing irrigation facilities in Korea. For the successful unified O & M of irrigation facilities covering whole irrigated paddy field in Korea, 950 billion won of O & M costs are required to keep up the marginal benefit of irrigation water as 2,800 billion won per year. The total O & M cost as 950 billion won should be allocated 40%, 380 billion won for O & M costs of irrigation facilities and 60%, 570 billion won for improvement of irrigation facilities. (5) The study investigated and reviewed the present O & M status of the irrigation facilities by small and medium irrigation fraternities. Most of the farmers belong to the irrigation fraternities preferred not only unified O & M but also KARICO take-over of the whole O & M activities of the irrigation facilities. The prevailing O & M cost per 10a expended by the Corporation was amounted to 104,890 won, while that of city and Gun governments was only amounted to 4,600 won per 10a. regarding the small amount of O & M cost expended by city and Gun governments, it is evident that the existing irrigation system have been managed ineffectively and deteriorated the facilities comparing that of KARICO. In conclusion, the Government could not satisfied the demand of irrigation water by suppling water with existing irrigation facilities. Therefore new additional investment and financial support for irrigation water development should be made to convert rain-fed and partially irrigated paddy fields into fully irrigated ones. The operation and maintenance cost should be supported to keep the marginal values of rice production of existing irrigation facilities in the national economy and to modernize the obsolete irrigation facilities. By unifying the existing dual O & M systems, all the farmers belong to the irrigated paddy fields have to be equally benefited and could be increased their farm income and be stabilized their rural lives.

  • PDF

Corrosion Rate of Structural Pipes for Greenhouse (온실 구조용 파이프의 부식속도 검토)

  • Yun, Sung-Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yoon, Yong Cheol
    • Journal of Bio-Environment Control
    • /
    • v.24 no.4
    • /
    • pp.333-340
    • /
    • 2015
  • Because soils in reclaimed lands nearby coastal areas have much higher salinity and moisture content than soils in inland area, parts of greenhouses embedded in such soils are exposed to highly corrosive environments. Owing to the accelerated corrosion of galvanized steel pipes for substrucrture and structure of greenhouses in saline environments, repair and reinforcement technologies and efficient maintenance and management for the construction materials in such facilities are required. In this study, we measured the corrosion rates of the parts used for greenhouse construction that are exposed to the saline environment to obtain a basic database for the establishment of maintenance and reinforcement standards for greenhouse construction in reclaimed lands with soils with high salinity. All the test pipes were exposed to soil and water environments with 0, 0.1, 0.3, and 0.5% salinity during the observation period of 480 days. At the end of the observation period, salinity-dependent differences of corrosion rate between black-surface corrosion and relatively regular corrosion were clearly manifested in a visual assessment. For the soils in rice paddies, the corrosion growth rate increased with salinity (0.008, 0.027, 0.036, and $0.043mm{\cdot}yr^{-1}$ at 0, 0.1, 0.3, and 0.5% salinity, respectively). The results for the soils in agricultural fields are 0.0002, 0.039, 0.040, and $0.039mm{\cdot}yr^{-1}$ at 0, 0.1, 0.3, and 0.5% salinity, respectively. The higher corrosion rate of rice-paddy soil was associated with the relatively high proportion of fine particles in it, reflecting the general tendency of soils with evenly distributed fine particles. Hence, it was concluded that thorough measures should be taken to counteract pipe corrosion, given that besides high salinity, the soils in reclaimed lands are expected to have a higher proportion of fine particles than those in inland rice paddies and agricultural fields.

Deterioration Evaluation Method of Noise Barriers for Managements of Highway (고속도로 방음벽 유지관리를 위한 방음벽 노후도 평가 방안)

  • Kim, Sangtae;Shin, Ilhyoung;Kim, Kyoungsu;Kim, Daae;Kim, Heungrae;Im, Jahae;Lee, Jajun
    • Journal of Environmental Impact Assessment
    • /
    • v.28 no.4
    • /
    • pp.387-399
    • /
    • 2019
  • This research aimed to prepare the classification of the damage types and the damage rating system of noise barriers for expressway noise barriers and to develop deterioration evaluation method of noise barriers by reflecting them. The noise barrier consists of soundproof panels, foundations and posts and the soundproof panels with 10 different types of materials are used in a single or mixed form.In this paper, damage of soundproof panel shows a single or composite damage, and thus a evaluation model of deterioration has been developed for noise barriers that can reflect the characteristic of noise barriers. Materials used mainly for soundproof walls were divided into material types for metal, plastic, timber, transparent and concrete. And damage types for noise barrier were classified into corrosion, discoloration, deformation, spalling and dislocation and damage types were subdivided according to the noise barrier's components and materials. Damage rating was divided into good, minor, normal and severe for each major part of noise barrier to assess damage rating of soundproof panel, foundation and post. The deterioration degree of noise barrier was evaluated comprehensively by using the deterioration evaluation method of whole noise barrier using weighted average. Deterioration evaluation method that can be systematically assessed has been developed for noise barrier using single or mixed soundproof panel and noise barrier with single or complex damage types. Through such an evaluation system, it is deemed that the deterioration status of noise barrier installed can be systematically understood and utilized for efficient maintenance planning and implementation for repair and improvement of noise barriers.

A Study on the Ordering Status of Traditional Landscape Design Service in Cultural Heritage (문화재의 전통조경설계용역 발주실태 연구)

  • Kim, Min-Seon;Kim, Choong-Sik;Lee, Jae-Yong
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.39 no.3
    • /
    • pp.33-41
    • /
    • 2021
  • This study identified the scale that traditional landscape design has taken up by analyzing a total of 1037 services for design of cultural heritage that had been ordered by the government agencies from 2018 to 2020, and has drawn characteristics of traditional landscape design focusing on major cases. The results are as follows. First, the number of order cases for traditional landscape design has shown differences annually in the services of design of cultural heritage, but the design amount has been found to have the similar average annually, which confirmed that the same level has been maintained each year. It was found that the number of cases of traditional landscape design requiring responsibilities or participations of landscape engineers for 3 years in the entire design had a high proportion of approximately 26%. Second, the traditional landscape design has required professional knowledge and experiences of landscape engineers that could not be replaced by the business operator for design of cultural heritage consisting of architects. The expertise has been shown differently depending on types of construction. First, the topographical design for the work to build a foundation has required understanding of ground shapes and its elevations and professional knowledge on calculation of the amount of the earth work and the remains maintenance technique etc. The plantation design has required basic knowledge on growth characteristics of trees and the environment for growth and understanding of the vegetation landscape of the past. Meanwhile, the design for traditional pavement and traditional landscape structures and facilities has required the expertise on traditional materials that are different from the modern ones and their processing and construction methods. The understanding of changes to water paths and ecosystem, the principles of fluids, and characteristics of each type of fluid was essential for the design for the ecological landscape work including the maintenance of a water system such as rivers etc. As such, the traditional landscape design has a scale accounting for approximately one fourth of the entire cultural heritage design and requires the expertise differentiated from other fields. This improves the provisions of the current law on limiting the actual design, suggesting the need for the establishment of a traditional landscape design company so that all traditional landscape designs can be carried out by landscape engineers.

A Study on the Pavement Status and Improvement Directions of the Viewing Road in Royal Tombs of Joseon Dynasty (조선 왕릉 관람로의 포장현황과 개선방향)

  • Paek, Chong-Chul;Hong, Youn-Soon
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.37 no.2
    • /
    • pp.66-73
    • /
    • 2019
  • The Royal Tomb of the Joseon Dynasty, which was listed as a UNESCO World Heritage site in 2009, is a cultural resource recognized for its 'outstanding universal value' around the world. The royal tomb of Joseon has been managed with an emphasis on the preservation of cultural assets since it was designated as a historical site in the 1970s, but it has received many visitors as a valuable historical and cultural resource and haven that connects the past and the present in today's bustling city. In order to investigate and analyze the current status of pavements in the royal palace in terms of quality and quantity, and to suggest the direction of improvement, this study conducted a complete survey of 53 royal palace viewing roads in 18 regions, and the results are as follows. First of all, problems are found in both the early Masato pavement of the creation, which was introduced with an emphasis on the preservation and protection of cultural assets, and the hardening pavement(KAP), which began to be used in the 1990s for the convenience of maintenance. In other words, the Masato pavement used to create a more environmentally friendly atmosphere of the Joseon royal tombs is showing a high percentage of use, but it lacks support for walking activities, such as the slippage of the pavement and water pooling during the rainy season or during the ice season. Also, hardening pavement introduced for convenience of maintenance, such as the movement of repair vehicles, is not functioning properly as it is damaged by physical deformation after construction. In addition, in awe zones such as parking lots, although the first image of the Joseon royal tombs is determined, the formation of the functional landscape centered on the carriageway does not harmonize with the traditional landscape, and, because of its lack of walking and environment-friendly features, there is a need for improvement, such as the experimental introduction of relevant pavement materials developed afterwards and continuous monitoring.

EVA Sheet and Butyl Rubber based Waterproofing·Anti-Corrosion Sheet for Corrosion Maintenance and Repairing in the Interior Side of the Large Steel Pipes in Water Treatment Facilities (상수도용 대구경 녹 발생 강관 내부의 보수 및 성능 유지를 위한 EVA 시트와 부틸고무를 합지한 자착식 방수방식 시트의 부착성능 평가)

  • An, Ki-Won;Kim, Byoung-Il;Oh, Sang-Keun
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.5 no.3
    • /
    • pp.267-274
    • /
    • 2017
  • This study discusses the applicability of environmental friendly EVA based butyl rubber self-adhesive waterproof sheet designed to prevent corrosion of large scale pipes used in the water treatment facilities during th water treatment process. The experiments conducted tested the waterproofing sheet's adhesion strength on the steel surface of the pipes and checked for whether the material has the proper response properties against the various environmental conditions. In addition, it the sheet adhered to the steel pipe was to see if the adhesion hold against the water pressure due to the ingress of inflow water. Finally, the waterproofing sheet's adhesion strength was tested on a rusted steel surface to confirm whether the material has the necessary properties to secure stable adhesion strength and prevent corrosion of steel pipes at the same time during the process of installation or maintenance. As a result, the self-adhesive waterproof sheets showed that all attachments in the untreated, long term pressuring, immersion in chemical substance (hydrochloric acid, hypochlorous acid, sodium hydroxide), low temperature ($-20^{\circ}C$) conditions showed a adhesion performance of higher than 1.5N/mm, which is the performance standard of KS F 4934. Also, in the testing to check for the adhesion property against inverse water pressure, it was observed that the adhesion failure did not occur even up to $3.0N/mm^2$ pressure. Also, in the process of assessing the adhesion performance on rusted steel surface, specimens after 12 hours of corrosion treatment was shown to have 2.1N/mm, and specimens after 168 hours of corrosion treatment was shown to have 2.0N/mm adhesion strength performance.