• Title/Summary/Keyword: Modification Value

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An Evaluation Study On Response Modification Factor of Unreinforced Mansonry Structure (비보강 조적조 건축물의 반응수정계수 설정에 관한 연구)

  • Kwon, Ki-Hyuk;Lee, Yong-Hwan;Yi, Waon-Ho;Lee, Jung-Han;Kang, Dae-Eon
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.33-36
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    • 2007
  • This study shows the basic data for setting up a response modification factor of unreinforcement masonry structure by considering and analyzing the experiment results of the domestic walls. If the result of this study compare with the value R of KBC-2005, 1.5, the average value, 1.2, is the low value. However, the maximum value, 2.57, is more than 70% bigger than the standard value. The standard value of overstrength factor, 2.5 is judged to have relatively bigger value than this study.

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An Improvement for Determining Response Modification Factor in Bridge Load Rating (응력보정계수 산정 방법 개선)

  • Koo, Bong-Kuen;Shin, Jae-In;Lee, Sang-Soon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.5 no.1
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    • pp.169-175
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    • 2001
  • Bridge load rating calculations provide a basis for determining the safe load capacity of bridge. Load rating requires engineering judgement in determining a rating value that is applicable to maintaining the safe use of the bridge and arriving at posting and permit decisions. Load testing is an effective means in calculating the rating value of bridge. In Korea, load carrying capacity of bridge is modified by response modification factor that is determined from comparisons of measured values and analysis results. The response modification factor may be corrupted by vehicle location error that is defined as the gap of test vehicle location between load testing and analysis. In this study, the effects of vehicle location error to structural response and response modification factor are investigated, and a new method for evaluating response modification factor is proposed. The random data analysis shows that the proposed method is less sensitive to vehicle location error than the present method.

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Aspirin (II) Structure-Activity Relationship of Salicylates and Improvements of Their Therapeutic Value through Structural Modification

  • Kim, Dong-Han
    • Archives of Pharmacal Research
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    • v.2 no.1
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    • pp.71-78
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    • 1979
  • Since the introduction of aspirin as a therapeutic agent in 1899, there have been numerous attempts at the improvement of its therapeutic value through molecular modification. These endeavors have centered mainly around the following two approaches : (a) improvement of the potency by introduction of a suitable group or groups on the benzene ring; and (b) modification of the carboxylic acid group, which is thought to be an immediate cause of the irritant effect.

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Surface Modification of Colloidal Silica Nanoparticles: Controlling the size and Grafting Process

  • He, Wentao;Wu, Danhua;Li, Juan;Zhang, Kai;Xiang, Yushu;Long, Lijuan;Qin, Shuhao;Yu, Jie;Zhang, Qin
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2747-2752
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    • 2013
  • Surface modification of colloidal silica nanoparticles without disrupting the electric double layer of nanoparticles is a major challenge. In the work, silane was employed to modify colloidal silica nanoparticles without inducing bridge flocculation obviously. The effect of pH value of the silica sol, the amount of silane in feed, and reaction temperature on the graft amount and the final size of modified particles was investigated. The increased weight loss by TG and the appearance of $T_2$ and $T_3$ except for $Q_2$ and $Q_3$ signals by CP/MAS $^{29}Si$ NMR of the modified samples verified the successful grafting of silane. The graft amount reached 0.57 mmol/g, which was slightly lower than theory value, and the particle size remained nearly the same as unmodified particles for acidic silica sol at the optimum condition. For alkaline silica sol after modification, aggregates composed of several nanoparticles connected together with silane moleculars as the bridge appeared.

A Study on Extraction and Comparison of Digital Content Key Frame in UCC Service Environment

  • Jang, Eun-Gyeom
    • Journal of Korea Multimedia Society
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    • v.14 no.8
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    • pp.1020-1028
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    • 2011
  • In this paper, we proposed a mechanism that prevents indiscreet use of digital contents, verifies created content's copyrights to provide services to granted user and protects digital contents by law by authenticating the original digital content whenever an infringement of copyright occurs in UCC environments. The proposed mechanism uses specific information and features of contents as copyrights authentication information without additional information. Also, provides the fact of violation by inferring the modification of the original digital contents. That means this mechanism infers same or similar value from the contents; fraudulent use of content, modification of content color, modification of content format, modification of content resolution and illegal use of frame not principal key frame. In that point, we found that the inferred value from the content differed according to features of content modification.

A Study on the Development of TCM Urban-Mode (도시형-TCM 개발에 관한 연구)

  • 장영기;조경두
    • Journal of Korean Society for Atmospheric Environment
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    • v.9 no.2
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    • pp.132-139
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    • 1993
  • TCM has been used for many environmental impact assessments and many case studies in Korea. TCM was applied to urbvan areas and rolling terrains. But original TCM was developed for rural area, and this model could not reflect the characteristcs of these study sites. This paper analyzed the characteristics of TCM, and modified the algorithm of area source, and modified the vertical wind speed profile exponents and diffusion parameter to make it applicable in urban area. In the process of modification, an important error in area source calculation of original TCM program was found. So that was corrected as follows. $$ Before modification $QC = 0.79788456^*(0.5^*GRID)^**BA/(U(IA, IRUN)^*AA^*BA TCM09310$ After modification $QC = 0.79788456^*(500^*GRID)^**BA/(U(IA, IRUN)^*AA*BA) modified$ $$ Then original TCM and modified TCM-urban mode were compared, and it was found that predicted mean value by original TCM was 7 times higher than observed mean value. But mean value by modified TCM-urban mode was very similar to observed value.

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Study on Measuring Geometrical Modification of Document Image in Scanning Process (스캐닝 과정에서 발생하는 전자문서의 기하학적 변형감지에 관한 연구)

  • Oh, Dong-Yeol;Oh, Hae-Seok;Rhew, Sung-Yul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.8
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    • pp.1869-1876
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    • 2009
  • Scanner which is a kind of optical devices is used to convert paper documents into document image files. The assessment of scanned document image is performed to check if there are any modification on document image files in scanning process. In assessment of scanned documents, user checks the degree of skew, noise, folded state and etc This paper proposed to how to measure geometrical modifications of document image in scanning process. In this study, we check the degree of modification in document image file by image processing and we compare the evaluation value which means the degree of modification in each items with OCR success ratio in a document image file. To analyse the correlation between OCR success ratio and the evaluation value which means the degree of modification in each items, we apply Pearson Correlation Coefficient and calculate weight value for each items to score total evaluation value of image modification degrees on a image file. The document image which has high rating score by proposed method also has high OCR success ratio.

Improvement of Rolling Force Estimation by Modificaiton Function for Hot Steel Strip Rolling Process (보정함수를 이용한 강판의 열간 압연하중 예측 정도향상)

  • 문영훈;이경종;이필종;이준정
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.5
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    • pp.1193-1201
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    • 1993
  • A new deformation resistance model for hot steel strip rolling process was formulated to improve the accuracy of roll force estimation. To improve the existing deformation resistance model more precisely, a modification function was introduced in this study. For the modification function, several factors considering material and operational conditions have been investigated and the optimal modification function was determined under the principle of minimum variability. The newly formulated modification function was applied to the deformation resistance model for ultra-low carbon steel and showed improved accuracy with about 30% decrease in terms of standard deviation of predicted roll force values against measured ones.

Challenges of Wood Modification Process for Plantation Eucalyptus: A Review of Australian Setting

  • GHANI, Ros Syazmini Mohd;LEE, Man Djun
    • Journal of the Korean Wood Science and Technology
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    • v.49 no.2
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    • pp.191-209
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    • 2021
  • Australia has significant wood resources in its native forest, but the resource available for harvest becomes lesser due to the conversion of native forest to conservation reserves. The natural occurrences of bushfires, droughts, and cyclones are highly destructive, making the situation worse. The shortage of wood resources is having a significant negative impact on Australia because wood is so scarce that they cannot meet domestic demands, especially durable wood. Australia cleared approximately 100 million hectares of its land to establish forest plantations, and two million trees were planted. However, most of these plantations are for pulpwood production; however, their application for high-value products is limited due to their undesirable properties. Wood modification is a process of improving unfavorable wood properties to be utilized for a wide range of applications. Australia has not adopted any of these modification processes; it still depends on the less toxic wood preservative to treat wood. This study focuses on the recent advancement in industrial wood modification worldwide and how it may be used to modify Eucalyptus wood for high-value applications. The opportunities and suggestions for Eucalyptus wood modification in Australia will be discussed. Before the study concludes, the future of commercial wood modification for Eucalyptus plantation in Australia will also be presented.

The Sensitivity Analysis for Structure Modification using Partial Differentiation (구조물의 동특성 개선을 위한 모드 매개변수의 민감도 해석)

  • Lee, Hae-Jin;Abu, Aminudin;Lee, Jung-Youn;Oh, Jae-Eung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.453-457
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    • 2006
  • This study predicts the modified structure of eigenvectors and eigenvalues due to the changes in the mass and the stiffness of the structure. The sensitivity method of natural frequency using partial differential are derived with respect to the physical parameter to calculate the structure modification. The method are applied to the 3 degree of freedom???slumped mass model by modeling the mass and stiffness, and then applies the method to a real crankshaft system. The position, direction of parameter change and modified value were predicted for modification. Finally the predicted value is used to investigate the magnitude of vibration and we found that the effect of modification results to reduce the level of magnitude vibration is satisfactory.

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