• Title/Summary/Keyword: reliable index

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A Study on Validation by the Development of a Science Process Skills Test with Science Experiments (과학 실험 평가 도구 개발을 통한 탐구 능력 평가의 타당화에 관한 연구)

  • Woo, Jong-Ok;Lee, Hang-Ro;Kim, Seung-Hun
    • Journal of The Korean Association For Science Education
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    • v.17 no.1
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    • pp.65-73
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    • 1997
  • The purpose of this study is to develop a valid and reliable instrument, applicable to high school Earth Science class experiment. In advance of developing items, I was selected 14 inquiry process skills and specified evaluative objectives for each of them to develop scales and criteria for them. I developed 28 evaluation items for 5 experiment subjects among those of high school Earth Science class. The first field trial was performed a sample of 5 high school students, and the second one using a sample of 25 high school students. The results are as follows. (1) The content validity and reliability(Cronbach $\alpha$) of the developed items were 82.7% and .86, respectively, the developed instrument in this study is considered valid and reliable. (2) The average difficulty index was .69 and the discrimination index was .30. (3) Answer sheets based on the reported results were rated 5 teachers and Inter-rater Reliabilitiy and Inter-rater Consistency were analyzed, its indices were .80 and .76, respectively. (4) The developed items show a low coefficient of .45 with TESIS, a set of paper-and-pencil test items developed by Lee, Hang-Ro(1991). That the experiment assessment is solely subject to the rater's viewpoint has been one of the major problems raised concerning the matter. This research, however, shows that a set of more specified scales and criteria for the evaluation will make it more valid, reliable and efficient.

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Evaluation of the Seismic Performance of Existing Building Structures (기존 철근콘크리트 건축물의 내진성능 평가)

  • 우운택
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.239-244
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    • 2000
  • The necessity of the seismic performance evaluation of existing building structures is raised through the Taiwan earthquake in 1999. In this study, the methods of seismic performance evaluation of existing building structures in U.S.A. and Japan were reviewed, applied them to the three-story office building structures in Seoul. It is found out that it is possible to establish the seismic performance evaluation index of RC structure which meet Korean seismic code. Also it is concluded that if sufficient experimental and analytical data could be obtained, a reliable index for the evaluation of seismic performance of existing structures should be established in Korea.

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Study on Risk Assesment of Debris Flow using GIS (GIS를 이용한 토석류 위험성 평가에 관한 연구 (소규모 개발지역 중심으로))

  • Chang, In-Soo;Park, Eun-Young;Park, Ki-Bum;Kim, Sungwon
    • Journal of Environmental Science International
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    • v.22 no.2
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    • pp.225-234
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    • 2013
  • The relationship between debris flow and topographical factors is essential for the reliable estimation of soil loss. The objective of this paper is to estimate stability index and soil loss for assessing landsliding risk caused by debris flow. SIMAP and RUSLE are used to estimate stability index and soil loss, respectively. The landsliding risk area estimated by using SIMAP is found to be different from the large land area estimated by RUSLE. It is found that the spatial distribution of soil cover significantly influences landsliding risk area. Results also indicate that stability index and soil loss, estimated by soil cover factor, improve the assessment of landsliding risk.

The Relationship of Bone Mineral Density to Growing Age (유소년기 골밀도와 성장과의 상관관계)

  • Hong Sung Min;Shin Jung Sik;Han Eun Ok;Ahn Joong Hwan;Han Seung Moo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.10
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    • pp.1451-1457
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    • 2004
  • Bone density parameters of children, unlike that of adult, might reflect growth effect along longitudinal direction as well as bone mass. The clinical test was performed for 859 male/female children with age 6-16 years. Ultrasonic imaging system was used to measure bone density, and relationship of bone density to age was evaluated. The bone quality index appeared to be highly correlated with age for male/female children. It was found that bone quality index rose rapidly in the first growth period. The bone quality index was then kept almost unchanged in the period of puberty, and slowly rose after puberty. It was also found that growth of female stopped earlier than that of male. Also, if more clinical examinations are performed by applying various sizes of region of interest, relationship between bone density and age is expected to be more reliable.

Estimation of Soil Volume Conversion Factors using Nondestructive Testing Methods (비파괴시험기법을 이용한 토량환산계수 산정 방법 제시)

  • Son, Thai An;Ryu, Hee-Hwan;Cho, Gye-Chun;Hong, Eun-Soo;Jin, Gyu-Nam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.717-721
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    • 2010
  • Soil volume conversion factors are used for estimation of an excavated the soil volume which will be removed or added in levelling the ground surface of a construction site. An accurate evaluation method will help us reduce a construction cost and time consuming. In this study, we performed the laboratory tests, including grain size measurement, water content, specific gravity, porosity, density and XRD tests, to suggest reliable soil volume conversion factors and weathering indices in field using nondestructive methods. The weathering index and soil volume conversion factor L are obtained for different types of soils. At results, the CIW index is the best method measuring the weathering index and the factor L is relative to natural porosity, void ratio, density and dry density.

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A Study on the Construction Vibrations Prediction of Bridge Structures using the Reliability Index (신뢰성 지수를 이용한 교량 구조물의 건설진동 예측에 관한 연구)

  • 박연수;우정하;전양배;김응록;김동현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.442-449
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    • 2003
  • This study presents a new analysis of blast vibration equations of a bridge structures using a reliability index. Changing the reliability makes each blast vibration equation. The blast equations are divided into three classes, having 50%, 90% and 99.9% at ${\beta}$=0, 1.28 and 3 respectively. In the result of this research, the assumption equations which used ${\beta}$=1.28 is suitable. By using these blast equations, it is possible for users to predict reliable ground vibration values upon demand.

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Assessment of cerchar abrasivity test in anisotropic rocks

  • Erarslan, Nazife
    • Geomechanics and Engineering
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    • v.17 no.6
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    • pp.527-534
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    • 2019
  • There have been developed a number of methods to assess the abrasivity of rock materials with the increased use of mechanized rock excavation. These methods range from determination of abrasive and hard mineral content using petrographic thin section analysis to weight loss or development of wear flat on a specified cutting tool. The Cerchar abrasivity index (CAI) test has been widely accepted for the assessment of rock abrasiveness. This test has been considered to provide a reliable indication of rock abrasiveness for isotropic rocks. However, a great amount of rocks in nature are anisotropic. Hence, viability assessment of Cerchar abrasivity test for the anisotropic rocks is investigated in this research. The relationship between CAI value and quartz content for the isotropic rocks is well known in literature. However, a correlation between EQ, F-Schimazek value, Rock Abrasivity Index (RAI) and CAI of anisotropic rocks such as phyllite was done first time in literature with this research. The results obtained with this research show F-Schimazek values and RAI values should be considered when determination of the abrasivity of anisotropic rocks instead of just using Cerchar scratch test.

DATA MINING-BASED MULTIDIMENSIONAL EXTRACTION METHOD FOR INDICATORS OF SOCIAL SECURITY SYSTEM FOR PEOPLE WITH DISABILITIES

  • BATYHA, RADWAN M.
    • Journal of applied mathematics & informatics
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    • v.40 no.1_2
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    • pp.289-303
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    • 2022
  • This article examines the multidimensional index extraction method of the disability social security system based on data mining. While creating the data warehouse of the social security system for the disabled, we need to know the elements of the social security indicators for the disabled. In this context, a clustering algorithm was used to extract the indicators of the social security system for the disabled by investigating the historical dimension of social security for the disabled. The simulation results show that the index extraction method has high coverage, sensitivity and reliability. In this paper, a multidimensional extraction method is introduced to extract the indicators of the social security system for the disabled based on data mining. The simulation experiments show that the method presented in this paper is more reliable, and the indicators of social security system for the disabled extracted are more effective in practical application.

Calculating the h-index and Its Variants Considering the Number of Authors in a Paper (공저자 수를 고려한 h-지수 산출)

  • Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.33 no.3
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    • pp.7-29
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    • 2016
  • The h-index is a popular bibliometric indicator for evaluating individual researchers. However, it has been criticized for its inconsistency with reflecting increased number of citations and disregarding the number of co-authors in a paper. In order to overcome these problems, we examined the g-index and other Hirsch-type indices considering the number of co-authors. Test data collection was extracted from Korean Citation Index database published from 2004 to 2013. The results of this study are as follows: First, g-index is more reliable indicator than h-index with consistency. Second, number of co-authors must be considered to maintain the h-index as an complex indicator applying the quality and the quantity of research performance. Finally, hc-index and gc-index, with fractionalised counting of the papers, can fairly measure the research performance of humanities researchers, and successfully prevent specific disciplines or institutions occupying majority of top rankings.

Developing Airport Safety Performance Indicators and Index - The Case of Incheon Airport Airside -

  • In Kie Na;Yu-Jin Choi
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.31 no.3
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    • pp.103-118
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    • 2023
  • An indicator system is an effective way to monitor ongoing safety status. Current aviation safety measurements account for many qualitative technical and lagging indicators. Conversely, quantitative and leading indicators have only a tiny proportion. This research added more quantitative leading indicators and reviewed them to harmonize lagging and leading indicators to measure airport safety and provide an index. The South Korean national gate, Incheon International Airport's indicators, were applied as primary data to verify this research practically. Then, examples from International and national authorities were reviewed and extracted for use. Fifty-five safety specialists participated in the focus group discussion and three rounds of the Delphi survey. Finally, 51 sub-indicators were newly chosen. After this process, weights for each indicator could be assigned using the AHP (Analytical Hierarchy Process) to provide an integrated index. The result of the simulation with newly added indicators in the past five years (2020-2022) reliable trend showed in indicators and integrated index. Moreover, this allows monitoring the status of the details of indicators and holistic insight. This study considered that it is more suitable for a single company or service provider to use it according to the exact situation than in a macro- and general-purpose at the country or regional level.