• Title/Summary/Keyword: Quality Maintenance

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A Model of Systems Management for Quality of Service in ATM Networks (ATM 망에서 Qos를 위한 시스템 관리의 모델)

  • Lee, Jae-Oh;Park, Phan-Woo;Lee, Kee-Hyun;Cho, Kuk-Hyun
    • The Transactions of the Korea Information Processing Society
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    • v.2 no.6
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    • pp.918-926
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    • 1995
  • In this paper, we study on the systems management for managing ATM network which is especially related to the management of Quality of Service(QoS). QoS management is considered as monitoring function. Therefore, we establish the management model of control and information aspects to manage ATM layer which has resource control, Operation and Maintenance (OAM) functions for performance management and monitoring functions. In particular, we focus on the effective processing of reported performance information caused by the indication of QoS degradation being represented as "QoSAlarm". In order to perform these management activities, the manager can process problem reports of QoS degradation in the proposed manner which uses the priority concepts based on QoS classes. In this circumstance, it is possible to take recovery actions in a predetermined and limited time for managed objects with fault and performance problems.

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The Effects of Edible Coating and Hurdle-Technology on Quality Maintenance and Shelf-Life Extension of Seafood (식용 코팅 및 허들기술이 수산물의 품질 유지와 저장성 연장에 미치는 영향)

  • Baek, Ji Hye;Lee, So-Young;Oh, Se-Wook
    • Journal of Food Hygiene and Safety
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    • v.35 no.3
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    • pp.205-212
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    • 2020
  • Foodborne diseases occur frequently and have various being related to the intake of contaminated foods. Seafood products are susceptible to contamination due to higher water content and microorganisms, which combine to give them a short shelf-life. Various approaches have been applied to overcome this problem. Edible coatings that are also biodegradable and biocompatible have been discussed as one of the applicable solutions. These coatings can actually help to maintain seafood quality by inhibiting the growth of microorganisms and delaying the loss of moisture. This paper presents the effects of various natural bio-polymers, antimicrobial substances and physical sterilization techniques such as gamma irradiation, ultraviolet (UV) sterilization, and light-emitting diode (LED) sterilization on seafood coatings.

A study on Determination Method of the Compliance Concentration of Effluent Limitation from Public Sewage Treatment Works in the Jinwee-stream Watershed Sewer System (유역하수도 공공하수처리시설의 방류수 수질 준수농도 설정방안 연구: 진위천 수계를 중심으로)

  • Jeong, Dong-Hwan;Cho, Yangseok;Kim, Youngseok;Ahn, Kyunghee;Chung, Hyen-Mi;Kwon, Ohsang
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.4
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    • pp.493-502
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    • 2015
  • In accordance with the Watershed Sewer System Maintenance Plan enforced on February 2, 2013, the different compliance concentration of effluent limit be applied to effluent discharged from public sewage treatment works(PSTWs) in each watershed on the basis of water quality thereof. With the introduction of watershed sewer system, it is necessary to set the compliance concentration of effluent limit for PSTWs situated in the watershed, by region and PSTW size, to achieve water quality criteria for regional watersheds or target water quality under TMDL program. Watershed Environmental Agencies establish the Watershed Sewer System Maintenance Plan and set the compliance concentrations of effluent limit for PSTWs under the plan. The agencies plan to apply tougher effluent BOD concentration limits in Class I to IV areas. Effluent BOD concentration limits will be toughened from 5~10 mg/L to 3 mg/L in class II~III areas, from 10mg/L to 5mg/L in class IV areas. Uniform application of effluent BOD concentration limits to PSTWs in the watershed sewer system need to be complemented considering type of sewage treatment technology employed and watershed characteristics. Therefore, this study presents method to determine the compliance concentration of effluent limit from PSTWs in the watershed.

Evaluation on Structural Stiffness and Grouting Efficiency of Concrete Track using Elastic Wave Tests (탄성파 기법을 이용한 콘크리트궤도의 구조강성 및 충전상태 평가에 관한 연구)

  • Lee, Il-Wha;Joh, Sung-Ho;Jang, Seung-Yup
    • Journal of the Korean Society for Railway
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    • v.12 no.1
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    • pp.55-64
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    • 2009
  • Recently, concrete track is replacing ballast track for efficient and economic maintenance of track. It considerably offer less maintenance, a longer service life and reduced life-cycle costs. With the aim of achieving high-quality track construction work, of developing tools for quality assurance in new construction and for later technical inspection of material condition, a quality strategy has to be developed. For these purpose, NDT which is using the seismic wave has carried out in situ studies in the test construction section. The used NDT are SASW test, impact echo test and continuous impact echo test. The test is performed 5,353 times on 49 pre-cast concrete track panels to verify the stiffness structure and grouting efficiency of the track structure. To conclude, because of the non-homogeneous characteristic of concrete material. it is restricted to apply the elastic wave test at some aspect. However it is possible to acquisite a sufficient reliability about structural stiffness and grouting efficiency of concrete track.

The Fundamental Study on Quality Properties of Binary Blended Concrete according to Water Reducing Performance of Chemical Admixture and Estimation Equation of Compressive Strength (화학 혼화제의 감수 성능에 따른 2성분계 콘크리트의 품질특성 및 압축강도 추정식에 관한 기초적 연구)

  • Kim, Kyung-Hwan;Oh, Sung-Rok;Choi, Byung-Keol;Choi, Yun-Wang
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.1
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    • pp.9-17
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    • 2016
  • In this study, binary blended concrete mix with fly ash and ground granulated blast furnace slag was prepared according to 3 level of water reduction performance of chemical admixture (0%, 8% and 16%) and 3 level of water-cement ratio (40%, 45% and 50%) for evaluation of quality properties of binary blended concrete according to performance of chemical admixture. concrete mix was carried out repetition test of three times in order to secure the reliability. As a result, compressive strength according to performance of chemical admixture was found that difference of strength was about 20% occurred, chemical admixture was showed that a great influence on qualities of concrete. In addition, reflected the effect of performance of chemiacal admixture, prediction model equations for concrete compressive strength was proposed, it was found that more than 85% of the high correlation.

Repair and Replacement Methodology for Electrical Equipment Used in Nuclear Power Plants (원자력발전소 전기기기의 보수, 교체 방법론)

  • Park, Chulhee;Park, Wan-gyu;Lee, Manbok;Kim, Choon-sam
    • Proceedings of the KIPE Conference
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    • 2018.07a
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    • pp.177-179
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    • 2018
  • After Fukushima nuclear accident at 2011, nuclear industrial has been focused on operation and maintenance phase, not design and construction phase. Continued good operating performance of nuclear power plants has been the best critical issue to nuclear utilities. Replacement for complete components as well as parts of components is being procured because nuclear utilities must maintain safety and reliability of operating nuclear power plants. However, many suppliers and manufacturers are giving up a nuclear quality assurance program under reduction in new construction of nuclear power plants. It is able to be increased difficulty in procuring spare parts to support operations and maintenance of nuclear power plants. Over 20% of nuclear power plant equipment in some countries is obsolete. Owing to obsolescence of nuclear safety-related items and/or withdrawing a nuclear quality assurance program of suppliers and manufactures, some replacement item and part might be procured to the item not covered by appendix B to USNRC 10 CFR Part 50. Under various methods of the nuclear repair and replacement methodology, utilities are supposed to establish a typical program for a repair and replacement of an electrical equipment and its parts in conjunction with a nuclear quality assurance. Concerning this typical program, this study suggests the repair and replacement methodology of electrical equipments used in nuclear power plants by procurement of a power supply, based on nuclear regulations, codes, standards, guidelines, specific and general technical information, etc..

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A Study on the Development of Oxygen Cluster Ion Generator for Sterilization of Bio Clean Room(BCR) (Bio Clean Room(BCR)의 멸균을 위한 산소 클러스터이온 발생 장치 개발에 관한 연구)

  • Park, Dong-Il;Chung, Kwang-Seop;Kim, Young-Il;Kim, Sung-Min
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.25 no.1
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    • pp.7-13
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    • 2013
  • Bio Clean Room(BCR) and pharmaceutical product manufacturing facilities require careful assessment of many factors, including HVAC, controls, room finishes, process equipment, room operations, and utilities. Flow of equipment, personnel, and product must also be considered along with system flexibility, redundancy, and maintenance shutdown strategies. It is important to involve designers, operators, commissioning staff, quality control, maintenance, constructors, validation personnel, and the production representative during the conceptual stage of design. Critical variables for room environment and types of controls vary greatly with the clean space's intended purpose. It is particularly important to determine critical parameters with quality assurance to set limits and safety factors for temperature, humidity, room pressure, and other control requirements. In this paper, oxygen cluster ion equipment was utilized in order to enhance the indoor air quality and to prevent the airborne infection of ward in hospital. Moreover, the performance test of the equipment was also performed in order to develop the optimal sterilization system of BCR using the equipment.

A Study on the Nano Silica-Sol Coating for Improving Performance of Recycled Aggregate (순환골재의 성능향상을 위한 나노실리카졸의 코팅에 관한 연구)

  • Kim, Seong-Soo;Lee, Jeong-Bae;Ko, Ji-Soo;Kim, Il-Kon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.4
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    • pp.84-90
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    • 2013
  • In this study we propose an effective method, Coating processing methods, which can improve the quality of recycled aggregate relatively easily without new equipment investment and complex treatment process and verify the improved effect using the devised method, Coating processing methods. To attain the research aim we used adequately diluted silicate solution for coating and carried out several property valuation for twelve types of material with different coating method. Also we formed concrete with coated aggregates which showed the best property. In conclusion the aggregates with the method of repeated impregnation in the silicate and drying showed the most excellent quality while other coating methods also resulted in an improvement of aggregate quality but failed to meet the KS Standard. Lastly with the optimal material we could obtain the approved compressive strength from the concrete allowing it to be utilized for road facility of which standard compressive strength of design is under 24MPa.

Effect of Transportation Conditions and Plant Growth Regulator on the Maintenance of Freshness and Quality of Cut Chrysanthemum 'Baekma' (절화국화 '백마'의 수송조건 및 생장조절제 처리가 선도유지 및 품질에 미치는 효과)

  • Suh, Jeung Keun;Kim, Ji Hee;Kim, Kyoung Ok
    • FLOWER RESEARCH JOURNAL
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    • v.19 no.4
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    • pp.206-211
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    • 2011
  • This study was carried the effect of transportation conditions and plant growth regulator on the maintenance of freshness and quality of cut Chrysanthemum 'Baekma'. The quality of cut chrysanthemum 'Baekma' which were stored at $5^{\circ}C$ was better than those of stored at $20^{\circ}C$ and control. When cut mum 'Baekma' was transported stacking boxes with vertical condition after dipping in distilled water, flowering degree, flower size, days to flower appearing degree, and bent neck were delayed. Flowering degree was delayed by $10mg/L^{-1}$ uniconazole spraying, The days to bent neck was delayed by 1,000x daminozide spraying.

A Study on the Qualification System for Raising Engineers of Maintenance for Apartment Houses - Based on the Qualification System of the United States - (공동주택 유지관리전문인력 육성을 위한 자격체계에 관한 연구 - 미국의 자격체계를 중심으로 -)

  • Park, Sang Hoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.1
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    • pp.169-179
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    • 2011
  • Korea owns vast amount of apartment houses no less than those of world prominent countries, but did not pay enough efforts to maintain existing apartment houses and develop policies to reuse them due to growth driven policy of housing supply like construction of new houses. Korea constructed tremendous amount of houses in short period through government led forced house supplying policy, and resulted in excess houses such that present house supply rate happened to be reaching 110%. However, recently there are growing demand of change in housing policy due to social environmental changes like low birth rate and aging of society etc and nationals' demand for improvement of residential quality. When such social changes are demanded and 80% of apartment houses in Korea are less than 20 years old, renovations and remodeling of apartment houses are anticipated to emerge as important matter. In particular, the apartment houses in Seoul and the 1st generation new cities like Bundang and Ilsan etc have passed considerable period of time after construction and require safety measure, it is quite impending to raise engineers for the maintenance of existing apartment houses. Therefore, in this paper, direction for the raising of maintenance engineers in Korea was proposed through analysis of relevant qualification system for the apartment houses maintenance engineers in the U.S.