• Title/Summary/Keyword: quality enhancement

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Evaluation on the Mechanical Performance of Low-Quality Recycled Aggregate Through Interface Enhancement Between Cement Matrix and Coarse Aggregate by Surface Modification Technology

  • Choi, Heesup;Choi, Hyeonggil;Lim, Myungkwan;Inoue, Masumi;Kitagaki, Ryoma;Noguchi, Takafumi
    • International Journal of Concrete Structures and Materials
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    • v.10 no.1
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    • pp.87-97
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    • 2016
  • In this study, a quantitative review was performed on the mechanical performance, permeation resistance of concrete, and durability of surface-modified coarse aggregates (SMCA) produced using low-quality recycled coarse aggregates, the surface of which was modified using a fine inorganic powder. The shear bond strength was first measured experimentally and the interface between the SMCA and the cement matrix was observed with field-emission scanning electron microscopy. The results showed that a reinforcement of the interfacial transition zone (ITZ), a weak part of the concrete, by coating the surface of the original coarse aggregate with surface-modification material, can help suppress the occurrence of microcracks and improve the mechanical performance of the aggregate. Also, the use of low-quality recycled coarse aggregates, the surfaces of which were modified using inorganic materials, resulted in improved strength, permeability, and durability of concrete. These results are thought to be due to the enhanced adhesion between the recycled coarse aggregates and the cement matrix, which resulted from the improved ITZ in the interface between a coarse aggregate and the cement matrix.

Effects Study on the Accuracy of Photochemical Modeling to MM5 Four Dimensional Data Assimilation Using Satellite Data (위성자료를 이용한 MM5 4차원자료동화가 광화학모델의 정확도에 미치는 영향 고찰)

  • Lee, Chong-Bum;Kim, Jea-Chul;Cheon, Tae-Hun
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.4
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    • pp.264-274
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    • 2009
  • Concentration of Air Quality Models (CMAQ) has a deep connection with emissions and wind fields. In particular the wind field is highly affected by local topography and plays an important role in transport and dispersion of contaminants from the pollution sources. The purpose of this study is to examine the impact of interpolation on Air quality model. This study was designed to evaluate enhancement of MM5 and CMAQ predictions by using Four Dimensional Data Assimilation (FDDA), the SONDE data and the national meteorological station and the MODerate resolution Imaging Spectroradiometer (MODIS). The alternative meteorological fields predicted with and without MODIS data were used to simulate spatial and temporal variations of ozone in combined with CMAQ on June 2006. The result of this study indicated that data assimilation using MODIS data provided an attractive method for generating realistic meteorological fields and dispersion fields of ozone in the Korea peninsular, because MODIS data in 10 km domain are grid horizontally and vertically. In order to ensure the success of Air quality model, it is necessary to FDDA using MODIS data.

Enhancement of Seed Germination by Aging, Cold-stratification, and Light Quality during Desiccation in Burcucumber (Sicyos Angulatus L.)

  • Kang, Jin-Ho;Jeon, Byong-Sam;Lee, Sang-Woo;Choe, Zhin-Ryong;Shim, Sang-In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.1
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    • pp.13-16
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    • 2003
  • Seeds of burcucumber were treated with accelerated aging, cold-stratification, and light quality illuminated during desiccation to enhance their germination and seedling emergence. The germination was increased by aging and cold-stratification although the latter treatment showed greater effectiveness than the former one. In the combined treatment of aging 6 days at $45^{\circ}C$ and cold-stratification, the germination was promoted under longer period of cold-stratification to reach nearly 100% in 3 week cold-stratification on the ninth day from sowing. In the sequentially combined treatment of aging, cold-stratification, and light quality during 24 hour desiccation at $35^{\circ}C$, no-stratified seeds showed the highest rate in red light treatment but the lowest in far-red light. This implies that the phytochrome action run during the desiccation of imbibed seeds. The red light exposure during drying for the cold-stratified seeds after aging accelerated the germination even more than the dark treatment and germinated 100% on the next day of sowing. It is concluded that the sequential treatment of aging, cold-stratification, and red light illumination during desiccation can highly promote percentage and speed of burcucumber seed germination.

A Visual Quality Enhancement of Medical Image Using Optimized High-Frequency Emphasis Filter (고주파 강조필터를 이용한 의료영상의 화질향상을 위한 최적화 방법)

  • Shin, Choong-Ho;Jung, Chai-Yeoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1681-1685
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    • 2014
  • The visual quality of medical image is an important factor for diagnosis accuracy. Therefore, the methods to improve the quality of medical image have studied. Among them, frequency domain filter is very powerful method to impove the visual quality of image. In this paper, the X-ray medical image using optimized high-pass filter was improved edges. The result image was improved edge and contrast of flat area using optimized high frequency emphasis filter. At last, the result image is to minimize the noise using the minimum mean square error(MMSE) filter. As a result, the proposed method has enhanced contrast and edge of the image in the contrast of existing filters, with the noise canceling effect.

The Study on the Reliability Enhancement for Solar Energy Resources Using the Data quality Management System in Korea (Focused on Data Error Analysis) (품질관리시스템을 활용한 태양에너지자원 신뢰성 향상에 관한 연구)

  • Jo, Dok-Ki;Kang, Young-Heack
    • Journal of the Korean Solar Energy Society
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    • v.27 no.1
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    • pp.19-27
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    • 2007
  • The Data quality management system(DQMS) organizes and helps manage and process time sequence data usually collected in monitoring networks and programs. DQMS places particular emphasis on data qualify while maintaining a highly organized and convenient structure for data. It operates with in a flexible and powerful commercial relational data base environment which can readily link to other software platforms from local spreadsheets to network server. The Korea Institute of Energy Research(KIER) has been solar radiation data since May, 1991 for 16 different locations. KIER's new data is expected to be extensively used by designer and researchers of solar systems in lieu of unreliable old ones. Unfortunately, the quality of the data has not always been properly mentioned. The purpose of this study is to systematically identify errors in such data set using DQMS in an effort to rehabilitate error-ridden old data. DET successfully uncovered solar radiation data that had questionable quality.

An Application of the QUAL II Model to the Keum River System (QUAL II 모형의 금강수계에의 적용)

  • 최흥식;이길성
    • Proceedings of the Korea Water Resources Association Conference
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    • 1987.07a
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    • pp.159-168
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    • 1987
  • Temporal and spatial prediction of water quality provides the necessary information to a profect planning, design, and model optimization for water quality mangement in a river system. In thes study, the QUAL II model is applied to the Keum River system from the downstream of Dae-Chong dam to the Great Pak-Je bridge. The advection-dispersion model of water quality based on the material balance and the numerical solution method of the model are presented. The enhancement of the model application is empha sized by comparing the observed and the simulated values of BOD, DO, and water temperature. Through these processes, the water quality states of the Keum River system are evaluated and the deoxignation rate, the reaeration rate, and Fair value are estimated. Also, the maintance of the target DO level with the control of the discharge from Dae-Chong dam is discussed.

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Metrics for Low-Light Image Quality Assessment

  • Sangmin Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.8
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    • pp.11-19
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    • 2023
  • In this paper, it is confirmed that the metrics used to evaluate image quality can be applied to low-light images. Due to the nature of low-illumination images, factors related to light create various noise patterns, and the smaller the amount of light, the more severe the noise. Therefore, in situations where it is difficult to obtain a clean image without noise, the quality of a low-illuminance image from which noise has been removed is often judged by the human eye. In this paper, noise in low-illuminance images for which ground truth cannot be obtained is removed using Noise2Noise, and spatial resolution and radial resolution are evaluated using ISO 12233 charts and colorchecker as metrics such as MTF and SNR. It can be shown that the quality of the low-illuminance image, which has been evaluated mainly for qualitative evaluation, can also be evaluated quantitatively.

A Framework for Automated Formwork Quality Inspection using Laser Scanning and Augmented Reality

  • Chi, Hung-lin;Kim, Min-Koo;Thedja, Julian
    • International conference on construction engineering and project management
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    • 2020.12a
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    • pp.13-22
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    • 2020
  • Reinforcement steel fixing is a skilled and manually intensive construction trade. Current practice for the quality assessment of reinforcement steel fixing is normally performed by fabricators and has high potential in having errors due to the tedious nature of the work. In order to overcome the current inspection limitation, this study presents an approach that provides visual assistance and inspection enhancement for inspectors to assess the dimensional layout of reinforcement steel fixing. To this end, this study aims to establish an end-to-end framework for rebar layout quality inspection using laser scanning and Augmented Reality (AR). The proposed framework is composed of three parts: (1) the laser-scanned rebar data processing; (2) the rebar inspection procedure integrating with AR; and (3) the checking and fixing the rebar layout through AR visualization. In order to investigate the feasibility of the proposed framework, a case study assessing the rebar layout of a lab-scaled formwork containing two rebar layers is conducted. The results of the case studies demonstrate that the proposed approach using laser scanning and AR has the potential to produce an intuitive and accurate quality assessment for the rebar layout.

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An Objective Image Quality Measurement Considering Skipped & Estimated Positions of Pixels in Image Scaling (영상 크기 변환에서 화소들의 생략 및 추정 위치를 고려한 객관적 영상 화질 측정)

  • Kim, Won-Hee;Moon, Kwang-Seok;Kim, Jong-Nam
    • Journal of Korea Multimedia Society
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    • v.16 no.8
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    • pp.934-942
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    • 2013
  • Image scaling is used for a variety of real-life applications. In order to evaluate the performance of transform functions, the image quality are compared together before and after processing. For the objective evaluation of the transform functions, the exact criterion of image quality is required, and various aspects approaches are practically performed. However, few researches have been conducted on image quality measurement considering the position of pixels that are skipped or newly generated in the process of the image scaling. Therefore this paper focuses on the objective image quality measurement for positions of skipped or estimated pixels in the image scaling. The proposed method generated new image quality measure considering the positional changes using a conventional measure and evaluated sensitivity about positional changes. Through this experiments, it is observed that conventional image quality measurement is definitely affected by positional changes of a skipped and estimated pixels. It is also confirmed that the proposed method is an objective criterion to represent image quality for positional changes of skipped or estimated pixels. The proposed method can be used as a criterion to evaluate the performance of image restoration or enhancement functions.

A Study on Kano Model Based Global Sustainable Quality Innovation Index of Single PPM Quality Innovation Movement (Kano Model을 기반으로 한 Single PPM 품질혁신운동의 글로벌 지속가능 품질혁신(GSQI) 지수에 관한 연구)

  • Lee, Hoe-Sik;Lee, Myung-Joo;Jeong, Hae-Jun
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.4
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    • pp.209-219
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    • 2007
  • Since 100PPM Quality Certification System has been established by the Industrial Advancement Administration in 1995, 100PPM duality Innovation movement has contributed much to the enhancement of qualify competitiveness of Korea's parts industry. And in 2000, raised to a higher level, Single PPM qualify Certification System has been established by the Small and Medium Business Adminstration. The quality target is below the 10ppm(parts per million) in outgoing qualify and delivered goods plus field claim. Recently 1.818 companies is received Single PPM Quality Certification from Government. Single PPM Quality Innovation movement is perfection movement which is suitable for 21C's social-economical criteria to pursuit of zero defect. The purpose of this study is to suggest the Kano Model based Global Sustainable duality Innovation(GSQI) Index to improve current problems of Single PPM Quality Innovation Movement.

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