• 제목/요약/키워드: long term maintenance

검색결과 771건 처리시간 0.027초

도로비탈면 녹화공사의 사후환경평가 항목 제언 (Suggestion of the Post-Environmental Evaluation of Road-side Cut Slope after Revegetation Works)

  • 김태국;김남춘;김은범;구민규
    • 한국환경복원기술학회지
    • /
    • 제21권4호
    • /
    • pp.75-86
    • /
    • 2018
  • This research was thereby made to study and analysis ecological, landscape, and stability qualities of roadside cut Slopes in expressways and national highways that went through revegetation works. Also, evaluation items and framework for integrated assessment of plant structure and restored state for the maintenance were suggested. Following is the summary of the result. firstly, for stabilization of introduced native plant species on roadside cut slops, assessment on the post-project environmental management through long-term monitoring and maintenance works must be made. It signifies a form of authentic recovery and restoration by the native plants. second, current evaluation framework on the test beds is well managed with clear evaluation standards and table while its method of assessing the post management with only test bed results lacks conformity with this study site. Newly developed evaluation framework on the post construction sites is estimated to be used as assessment standards on any roadside construction sites. Third, after site investigation distinction was observed among different revegetating construction types in the long-term perspective. Due to the different duration time of vegetation state between seed-spray measures(degraded in time) and layer-spray measure(maintained), the use of coarse straw-mat mulching work or Coir net was suggested in long term maintenance of cut slopes. forth, segmentation of post environmental assessment is organized into three large categories of "ecological", "stabile", and "landscape" qualities regarding post restoration quality and stability of slope through native plants with which categories marks 50, 30, 20 points of rates. fifth, components of the post environmental assessment were segmented in twelve categories driving results from former experimental construction and newly focused items on site. In the future, it is possible to propose a customized assessment method considering the location and location of construction work if the research on the application of post-environment assessment methods for road construction surface recording is conducted systematically.

Potential of Initial CA Condition on Quality Maintenance of 'Fuji' Apples during Export Simulation after Long-term Storage

  • Park, Youn-Moon;Park, Hyo-Geun
    • 원예과학기술지
    • /
    • 제30권4호
    • /
    • pp.400-408
    • /
    • 2012
  • Effects of initial controlled atmosphere (CA) treatment on quality maintenance of 'Fuji' apples were assessed and compared with 1-methylcyclopropene (1-MCP) treatment and continuous CA storage. Apples were harvested twice at different maturity, treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored for 8 months at $0^{\circ}C$ under 3 conditions: air, CA for the first month followed by air (initial CA), and continuous CA (full CA). CA storage was performed with 1.5 kPa $O_2$ and < 1.0 kPa ($N_2$ balance). Following long-term storage, export simulation, refrigerated shipment and local distribution, were performed by holding apples at $0^{\circ}C$ for 2 weeks and on the shelf at $20^{\circ}C$ for 7 days. Both the application of 1-MCP and CA storage reduced ethylene production and respiration rates. Initial CA storage was also effective on reducing the metabolism although the effects were not as noticeable as full CA. Full CA storage with or without 1-MCP treatment maintained titratable acidity, flesh firmness, and sensory quality at the acceptable to excellent level even after the export simulation following 8-month storage regardless of harvest maturity. In contrast, effects of initial CA storage were limited to the maintenance of firmness and texture in early-harvested apples. Overall results indicated that harvest maturity is the critical factor for export fruit quality after long-term storage when separate treatment of initial CA storage or 1-MCP treatment is applied as a postharvest program.

Management of Neighbor Cell Lists and Physical Cell Identifiers in Self-Organizing Heterogeneous Networks

  • Lim, Jae-Chan;Hong, Dae-Hyoung
    • Journal of Communications and Networks
    • /
    • 제13권4호
    • /
    • pp.367-376
    • /
    • 2011
  • In this paper, we propose self-organizing schemes for the initial configuration of the neighbor cell list (NCL), maintenance of the NCL, and physical cell identifier (PCI) allocation in heterogeneous networks such as long term evolution systems where lower transmission power nodes are additionally deployed in macrocell networks. Accurate NCL maintenance is required for efficient PCI allocation and for avoiding handover delay and redundantly increased system overhead. Proposed self-organizing schemes for the initial NCL configuration and PCI allocation are based on evolved universal terrestrial radio access network NodeB (eNB) scanning that measures reference signal to interference and noise ratio and reference symbol received power, respectively, transmitted from adjacent eNBs. On the other hand, the maintenance of the NCL is managed by adding or removing cells based on periodic user equipment measurements. We provide performance analysis of the proposed schemes under various scenarios in the respects of NCL detection probability, NCL false alarm rate, handover delay area ratio, PCI conflict ratio, etc.

장기간의 유지관리 실패로 인해 파절된 임플란트 피개의치 재수복 증례 (Retreatment of fractured implant overdenture due to long-term maintenance failure)

  • 김민지;홍성진;백장현;노관태;배아란;김형섭;권긍록
    • 대한치과보철학회지
    • /
    • 제56권3호
    • /
    • pp.235-242
    • /
    • 2018
  • 임플란트 피개의치에서 치주적, 보철적 유지관리는 보철물과 임플란트의 장기적 성공에 매우 중요한 요인이다. 유지관리의 실패는 임플란트 주위 골소실 및 보철물이나 구성품의 파절 및 마모로 인해 보철적 실패를 유발할 수 있다. 이 증례에서는 유지관리 실패로 파절된 임플란트 피개의치의 재치료를 위해 기존의 골드 milled bar를 코발트 크롬 milled bar로 외형에 방해되지 않는 형태로 재제작하였고, 하악의 기존 고정성보철은 임플란트 주변 골흡수와 환자의 전신적 문제로 인해 전략적으로 임플란트를 선택하여 두 개의 임플란트에 CM LOC을 연결하여 임플란트 피개의치를 제작하여 재수복하였다. 결과적으로 환자의 위생관리를 수월하게 하는 디자인의, 기능적 심미적으로 장기간 유지관리에 유리한 보철물로 수복하였고 정기적인 유지관리를 시행하였다.

현장 하중계 계측자료 분석을 통한 그라운드 앵커의 장기거동 예측 (Prediction of Long-term Behavior of Ground Anchor Based on the Field Monitoring Load Data Analysis)

  • 박성열;황범식;이상래;조완제
    • 한국지반공학회논문집
    • /
    • 제37권8호
    • /
    • pp.25-35
    • /
    • 2021
  • 현재 국내에서는 비탈면 및 구조물 안정성 확보를 목적으로 네일, 록볼트 등과 함께 그라운드 앵커 공법을 사용하고 있다. 이 중 장기목적으로 사용되는 영구앵커의 경우 사용기간 중 지지력과 내구성이 확보되어야 하나, 최근 연구 결과에 따르면 장기거동에 따른 잔존 긴장력 감소와 비탈면 변형 등의 현상이 보고되고 있다. 이와 같은 잔존 긴장력 감소 문제는 앞으로 지속적으로 증가될 것으로 전망되며, 이로 인한 유지관리 비용 증가 등의 문제가 불가피할 것으로 보인다. 이에 본 연구에서는 국내·외 문헌연구를 통해 영구앵커의 긴장력에 영향을 미치는 요인들을 파악하였으며, 과거 수행된 하중계 모니터링 자료를 분석한 선행연구들을 조사하였다. 이후, 이를 기초자료로 활용하여 실제 현장에서 수집한 하중계 계측자료를 분석하여 앵커의 긴장력 감소현황을 파악하였고, 그 장기하중감소특성을 분석하였다. 마지막으로 앞의 내용을 종합하여, 설치 직후 100일 부근의 단기 데이터를 통해 영구앵커의 장기하중감소특성을 예측하는 기법을 제안하였다.

교육시설물의 합리적인 유지관리를 위한 비용분류체계 (Cost Breakdown Structure for Reasonable Maintenance of Educational Facilities)

  • 정재혁;신한우;김태희
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2011년도 추계 학술논문 발표대회
    • /
    • pp.65-67
    • /
    • 2011
  • It is necessary to the development of the best maintenance system for applying the long-term maintenance plan using the cost breakdown structure in the educational facilities. This study developed the cost breakdown structure for the best maintenance system using the delphi method. For the convenience of maintenance, the maintenance cost breakdown structures are separated into building exterior wall, building inside wall, electric installation, heating installation and outdoor facilities. And these results atomized in each parts. And this study constructed the cost breakdown structure to maintenance's practicality and effectiveness through the expert analysis.

  • PDF

교육환경개선사업 공간단위 업무프로세스 개선방안 (Improvement Plan of Educational Facilities Maintenance based on Space Level)

  • 배창준;박상헌;조동현;구교진
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
    • /
    • pp.72-73
    • /
    • 2019
  • As the physical functions of school buildings and the changes in the functions of educational facilities due to social change are increasing, the demand for fundamental and long-term measures for the maintenance of educational facilities is expanding. However, depending on the function of the facility, the maintenance work has been carried out only when it is directly related to the safety problem, or when the request of the school facility manager is requested, rather than supporting preventive maintenance. In this study, we investigate the maintenance process of educational facilities and propose a method to manage the maintenance process of the educational facilities in the unit of space for establishing an efficient maintenance management system.

  • PDF

재령에 따른 고유동 경량골재콘크리트의 강도특성에 관한 실험적 연구 (An Experimental Study on the Strength Properties of Flowing Lightweight Aggregate Concrete with Age)

  • 전현규;유택동;서치호
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제2권4호
    • /
    • pp.186-193
    • /
    • 1998
  • The purpose of this research is to seek properties of flowing light-weight aggregate concrete and possibility of application. The experimental analysis results by using light-weight aggregate and industrial waste such flyash, furnace slag are as follow. 1) The research shows that flowing light-weight aggregate concrete of slump 23~27cm, slump flow 58~69 cm is possible, but material segregation is appeared above slump 26.5cm and slump flow 65 cm. 2) If mixing ratio of flyash is increase, strength deterioration is about 25 % in early age. It showed that effectiveness of long time strength improvement because strength manifestation ratio is above 95% in a long term. 3) This research showed possibility of substitution of blast furnace slag because strength deterioration by using mixing of furnace slag was appeared small deterioration range as below 10 %. 4) Each experimental compressive strength ratios were 77 %(1st week), 86 %(2nd week), 109 %(8th week), 115 %(13th week), 125 % (26th week) on the basis of 28 days. If mixing ratio of flyash is increase, long term strength increase ratio is improved.

  • PDF

유지관리 계측에 의한 터널 콘크리트 라이닝의 응력 분석 (Stress Analysis of Tunnel Concrete Lining for Maintenance Monitoring)

  • 우종태;이송
    • 콘크리트학회논문집
    • /
    • 제14권3호
    • /
    • pp.341-348
    • /
    • 2002
  • 유지관리 계측은 터널 구조물의 지속적인 안전성 확인과 최적의 유지관리가 되도록 객관적이고 연속적인 자료제공을 목적으로 한다. 최근 들어 각종 터널에 적용하는 사례가 급속하게 증가되고 있으나, 현재까지 터널에서 장기간 측정된 계측실적도 적고, 합리적인 분석방법 연구도 전무한 실정이다. 본 연구에서는 장기간 계측이 수행된 지하철 풍화대 통과 터널의 계측결과를 회귀분석하여 터널의 최종 지보재인 콘크리트 라이닝의 응력과 철근응력의 상관관계를 파악하였다. 또한, 터널 콘크리트 라이닝의 응력과 안전성의 분석을 통하여 유지관리 계측 빈도 및 관리 기준치의 현장 적용성을 검토하였다.

1형 양극성 장애 환자에서 리튬과 발프로산의 장기간 치료 효과에 대한 후향적 평가 : 2년 이상 치료받은 환자의 효과 비교 (Long-Term Treatment Response to Lithium and Valproate in Patients with Bipolar 1 Disorder Treated More Than 2 Years : A Retrospective Study)

  • 안성우;양소영;최유진;홍경수
    • 생물정신의학
    • /
    • 제23권4호
    • /
    • pp.185-192
    • /
    • 2016
  • Objectives Treatment response of bipolar disorders (BDs) to long-term mood stabilizers maintenance has not been well explored because of complicated clinical and treatment courses. This study aims at investigating long-term clinical response of BDs to lithium and/or valproate in a naturalistic setting of a tertiary-care university-affiliated hospital. Methods Subjects were 65 patients with bipolar I (BD-I) disorders who had been treated with lithium and/or valproate for more than two years at single bipolar disorder clinic. Long-term response to the best treatment based on treatment algorithms and the current clinical standard of care was retrospectively evaluated using the Alda Scale and the Clinical Global Impression Scale for use in bi-polar illness (CGI-BP). Patients were classified into full responder and partial/non responder groups based on the total score of the Alda Scale with the cut-off score generated from the frequentist mixture analysis of the authors' previous study. Results The mean duration of treatment with the index medication was 69.2 months. Baseline demographic and clinical characteristics were not different among three mood stabilizer groups (valproate, lithium, and combination groups). Twenty-one subjects were classified into full responder group (32.3%). Treatment response assessed by the Alda Scale and CGI-BP scores was not different between lithium and valproate groups. The Alda Scale scores were well correlated with the CGI-BP scores (p < 0.05). Conclusions One third of the patients showed a full response to the long-term lithium and/or valproate treatment in BD-I. The degree of response was similar between lithium and valproate groups.