• Title/Summary/Keyword: integrity index

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Assesment of Ecological Condition Improvement by Eco-Technological Restoration in a Small Stream (샛강의 생태공학적 복원공법 적용에 따른 생태환경 개선 효과)

  • Kwon, Tae-Ho;Lee, Jung-Ho
    • Korean Journal of Environment and Ecology
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    • v.21 no.5
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    • pp.442-448
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    • 2007
  • This study was carried out to assess the improved aspects of ecological conditions in a small stream, where eco-technological restorations such as gabion-crib mattress arrangement and soil-arresting wicker fence work had already been made up to stabilize the physically and ecologically damaged streambank. Six metrics by diatoms including species richness, Shannon diversity, saprobic index by DAIpo, percent sensitive diatoms, percent of Achnanthes minutissima, dominant index were analysed to assess the ecological integrity of small stream. By generalizing the changed values of six metrics on the stream flow from upper point(ST.1) to lower point(ST.3), it was found that the effect value of ecological condition improvement went up to as much as 33.9% on the average. The results suggested that eco-technological restoration treatment applied to this study is considerably effective for preserving the ecological integrity of small stream.

Failure Probability Assessment of an API 5L X52 Gas Pipeline with a Wall-thinned Section

  • Lee Sang-Min;Yun Kang-Ok;Chang Yoon-Suk;Choi Jae-Boong;Kim Young-Jin
    • International Journal of Precision Engineering and Manufacturing
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    • v.7 no.3
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    • pp.24-29
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    • 2006
  • Pressurized gas pipelines are subject to harmful effects from both the surrounding environment and the materials passing through them. Reliable assessment procedures, including fracture mechanics analyses, are required to maintain their integrity. Currently, integrity assessments are performed using conventional deterministic approaches, even though there are many uncertainties to hinder rational evaluations. Therefore, in this study, a probabilistic approach was considered for gas pipeline evaluations. The objectives were to estimate the failure probability of a corroded pipeline in the gas and oil industries and to propose limited operating conditions for different types of loadings. To achieve these objectives, a probabilistic assessment program was developed using a reliability index and simulation techniques, and applied to evaluate the failure probabilities of a corroded API-5L-X52 gas pipeline subjected to internal pressures, bending moments, and combined loadings. The results demonstrated the potential of the probabilistic integrity assessment program.

Failure Probability Assessment of Gas Pipelines Considering Wall-Thinning Phenomenon (감육현상을 고려한 가스배관의 파손확률 평가)

  • Lee Sang-Min;Yun Kang-Ok;Chang Yoon-Suk;Choi Jae-Boons;Kim Young-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.10 s.175
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    • pp.158-166
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    • 2005
  • Pressurized gas pipeline is subject to harmful effects both of the surrounding environment and of the materials transmitted in them. In order to maintain the integrity, reliable assessment procedures including tincture mechanics analysis etc are required. Up to now, the integrity assessment has been performed using conventional deterministic approaches even though there are many uncertainties to hinder a rational evaluation. In this respect, probabilistic approach is considered as an appropriate method for gas pipeline evaluation. The objectives of this paper are to estimate the failure probability of corroded pipeline in gas and oil plants and to propose limited operating conditions under different types of leadings. To do this, a probabilistic assessment program using reliability index and simulation techniques was developed and applied to evaluate failure probabilities of corroded API-5L-X52/X60 gas pipelines subjected to internal pressure, bending moment and combined loading. The evaluation results showed a promising applicability of the probabilistic integrity assessment program.

Prediction of Remaining Life for Corroded Pipelines (부식 손상된 파이프라인의 잔존 수명 예측)

  • JIN, Yeung-Jun
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.4
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    • pp.411-417
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    • 2004
  • Recently, researchers and engineers from, the development of reliability engineering and probability fracture mechanics, have begun to take seriously the reliability analysis and the integrity for a corroded pipeline. Pressurized pipelines containing active corrosion defects increase gradually both in extent, and depth with increased periods of exposure. This causes a reduction of the remaining strength and the carrying capacity of a pipeline; and creates uncertainty about the future capacity. The steps that are necessary in order to assess the integrity of corroded pipelines will be discussed in this paper utilizing results from an actual model.

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Studies on Genetic Stability of Micropropagated Plants and, Reintroduction in an Endemic and Endangered Taxon: Syzygium travancoricum Gamble (Myrtacae)

  • Ajith Anand
    • Journal of Plant Biotechnology
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    • v.5 no.4
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    • pp.201-207
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    • 2003
  • Tissue culture techniques arguably are an important approach for ex situ conservation of rare and endangered plant species. However, there is utmost importance on maintaining the genetic integrity of the introduced plants especially in tree species. To examine the genetic integrity of the micropropagated plants, we randomly screened few hardened plants of Syzygium travancoricum, a critically endangered tree taxon, using Randomly Amplified Polymorphic DNA (RAPD) markers. Twenty-three random. primers were tried and twenty-five polymorphic loci were identified. The dendrogram based on the Unweighted Pair-Group Method Arithmetic Average and Nei's similarity index depicted about 97% homology between the mother plants and micropropagated plants. Further, an attempt was made to reintroduce the micropropagated plants in the wild. Over three hundred small trees could be successfully established.

Damage Effects on the Natural Frequency of Concrete Pier (구체손상에 따른 콘크리트 교각의 고유진동수 변화)

  • Park, Byung-Cheal;Oh, Keum-Ho;Park, Seung-Bum
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.335-338
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    • 2005
  • This study was performed to verify that the impact vibration test on the damaged concrete pier can be adopted for assessment of the bridge substructure integrity. Using the experimental modal analysis, the dynamic property changes of the concrete pier are investigated according to the damage levels which are modeled by the loss of cross section area of the pier body. As a result of the impact vibration test, it is found that the natural frequency of the bridge substructure is reduced due to the damage on the pier such as loss of cross section area, and the natural frequency can be used for assessment of the integrity index.

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Changes in Physicochemical Properties of Rice Extrudate Due to Added Isolated Soy Protein (분리대두단백 첨가에 의한 쌀 압출성형물의 물리화학적 특성 변화)

  • Lee, Chan
    • The Korean Journal of Food And Nutrition
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    • v.23 no.1
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    • pp.114-117
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    • 2010
  • The effects of isolated soy protein(ISP) content on the physicochemical properties of extrudates from rice flour produced by a single-screw extruder were evaluated. The integrity index(II), nitrogen solubility index(NSI), rehydration ratio(RR), and density were measured as indices of the changes of physicochemical properties of rice extrudates. Increased amounts of ISP resulted in increased II but decreased RR and density. There was no change in the NSI value. It was concluded that the addition of ISP to the raw material could be helpful in texturization of rice extrudate.

A New Statistical Index for Detecting Cheaters on Multiple Choice Tests (다중선택 시험에서 부정행위자 발견을 위한 새로운 통계적 측도)

  • Han, Eun Su;Lim, Johan;Lee, Kyeong Eun
    • The Korean Journal of Applied Statistics
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    • v.26 no.1
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    • pp.81-92
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    • 2013
  • It is important to construct a firm basis for accusing potential violators of academic integrity in order to avoid spurious accusations and false convictions. Educational researchers have developed many statistical methods that can either uncover or confirm cases of cheating on tests. However, most of them rely on simple correlation-based measures, and often fail to account for patterns in responses or answers. In this paper, we propose a new statistical index denoted by a Standardized Signed Entropy Similarity Score to resolve this difficulty. In addition, we apply the proposed method to analyze a real data set and compare the results to other existing methods.

A Study on Damage Detection of Production Riser (생산 라이저의 손상 탐지에 대한 연구)

  • Je, Hyun-Min;Park, Soo-Yong
    • Journal of Navigation and Port Research
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    • v.39 no.3
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    • pp.179-184
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    • 2015
  • The purpose of this study is to provide appropriate methodology to ensure the safety and integrity of the production riser in offshore structure. In order to select integrity estimation methodology for production riser, level I and II Non-destructive Damage Evaluation (NDE) methods that were applied to existing structures are classified and reviewed. Numerical analysis is performed to verify the applicability and capability on damage detection of reviewed methods. As a result, the damage detection methodology using modal strain energy is more sensitive in detection of the damage than other methods. In practice, the number of sensors is limited due to the environmental and financial conditions. The impact on damage detection performance by reducing the number of sensors is systematically investigated through a series of numerical analyses and the results are discussed. The optimal number of sensor for the integrity estimation of production riser is recommended.

Rapid Bioassessments of Kap Stream Using the Index of Biological Integrity (생물보전지수(Index of Biological Integrity)의 신속한 생물평가 기법을 이용한 갑천 수계의 평가)

  • Yeom, Dong-Hyuk;Lee, Sung-Kyu;An, Kwang-Guk
    • Korean Journal of Environmental Biology
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    • v.19 no.4
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    • pp.261-269
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    • 2001
  • The purpose of present study was to introduce a multimetric approach, so called the Index of Biological Integrity (IBI) as a tool for evaluations of water environments. We used 11 metric systems for the IBI to evaluate stream conditions, based on the fish community, and modified 5 original metric attributes suggested by Karr (1981). Overall IBI values in Kap Stream averaged 36 (n = 5) and ranged 17${\sim}$49, indicating a 'fair condition' according to the modified criteria of Karr (1981) and U.S. EPA (1993). However, there were distinct differences in the IBI values among 5 study sites. The IBI values at sites 1, 2, and 3 were 49, 45, and 41, which indicated 'good${\sim}$excellent', 'good', and 'fair' condition, respectively, while values at sites 4 and 5 were 17 and 29, which indicated 'very poor' and 'poor', respectively. The minimum IBI at site 4 was probably due to continuous inputs of wastewater from wastewater disposal plants. The condition at site 4 resulted in predominance of tolerant species (50%), omnivore species (50%), and high abnormalies (43%). In the mean time, the IBI value at site 5, located near 5km downstream from the site 4, increased compared to that of site 4, and this seemed to be a result of recovery of water quality as the polluted water goes downward. We believe that present bioassessment methodology of IBI applied in this study may be used as a key tool to set up specific goals for stream restoration plans and dentify recovery levels of lotic ecosystems after restoration activities(i.e., prevention of point-source pollutant input, restoration of physical habitats, construction of riparian vegetation) as well as a biological measure diagnosing current stream conditions.

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