• Title, Summary, Keyword: Core Quality

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Chandler Wobble and Free Core Nutation: Theory and Features

  • Na, Sung-Ho;Roh, Kyoung-Min;Cho, Jungho;Yoo, Sung-Moon;Choi, Byungkyu;Yoon, Hasu
    • Journal of Astronomy and Space Sciences
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    • v.36 no.1
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    • pp.11-20
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    • 2019
  • Being a torque free motion of the rotating Earth, Chandler wobble is the major component in the Earth's polar motion with amplitude about 0.05-0.2 arcsec and period about 430-435 days. Free core nutation, also called nearly diurnal free wobble, exists due to the elliptical core-mantle boundary in the Earth and takes almost the whole part of un-modelled variation of the Earth's pole in the celestial sphere beside precession and nutation. We hereby present a brief summary of their theories and report their recent features acquired from updated datasets (EOP C04 and ECMWF) by using Fourier transform, modelling, and wavelet analysis. Our new findings include (1) period-instability of free core nutation between 420 and 450 days as well as its large amplitude-variation, (2) re-determined Chandler period and its quality factor, (3) fast decrease in Chandler amplitude after 2010.

CORE $SHELL^{TM}$: THE LATEST INNOVATION IN POLYMER TECHNOLOGY FOR THE PAPER INDUSTRY (코어쉘 : 제지산업에 있어서 고분자 기술의 최근 혁신)

  • Gerli, Alessandra;Johnson, Gray
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • pp.87-105
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    • 2003
  • A new polymer technology commercialized with the name of Core Shell has been developed by Ondeo Nalco Company. Laboratory evaluations have demonstrated that Core Shell polymers produce a floc with high shear resistance, making them the flocculants of choice for modern high-speed paper machines. Core Shell polymers provide significant papermaking benefits, when used as single component or in combination with microparticles. At this time, the new program has been successfully applied on more than 60 paper and board machines across the world. Implementation of Core Shell polymers with or without a microparticle provided better and more stable retention values and improvements in paper quality, system cleanliness and machine runnability.

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The Effects of Runner Core Pin on the Filling Imbalance Occurred in Multi Cavity Injection Mold (다수 캐비티 사출금형에서 러너 코어핀이 충전불균형에 미치는 영향)

  • Kang C. M.;Jeong Y. D.;Han K. T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • pp.39-42
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    • 2005
  • For mass production, usually injection mold has multi-cavity which is filled through geometrical balanced runner system. Despite geometrical balanced runner system, filling imbalances between cavity to cavity have always been observed. These filling imbalances are one of the most significant factors to affect quality of plastic parts when molding plastic parts in multi-cavity injection mold. Filling imbalances are results from non-symmetrical shear rate distribution within melt as it flows through the runner system. It has been possible to decrease filling imbalance by optimizing processing conditions, but it has not completely eliminated this phenomenon during injection molding processing. This paper presents a solution of these filling imbalances through using 'runner core pin'. The runner core pin which is developed in this study creates a symmetrical shear distribution within runner. As a result of using runner core pin, a remarkable improvement in reducing filling imbalance was confirmed.

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A Study on the Development of Evaluation Indicators for the Proposals of National Defense Core-Technology R&D Projects (국방핵심기술 연구개발의 제안서 평가를 위한 평가지표 개발에 관한 연구)

  • Kim, Chan-Soo;Cho, Kyu-Kab
    • IE interfaces
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    • v.21 no.1
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    • pp.96-108
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    • 2008
  • This paper proposes the systematic design approach for developing the evaluation indicators that evaluate the candidate proposals in the national defense core-technology R&D projects. To improve the validity and fairness of the evaluation indicators, the existing evaluation process in a military and a public sector are surveyed and also the existing evaluation system of the core-technology R&D programs for the national defense is analysed and discussed. A new system for the evaluation indicators is designed by using the axiomatic design, factor analysis and the analytic hierarchy process. It is expected that the proposed evaluation indicators contribute to enhance the fairness and the reliability of the evaluation process for the proposal of the national defense core-technology R&D projects.

Analysis of Construction Cases for Sequential PC Stairway Method (RC 계단실 연속화 시공을 위한 PC 계단 공법 현장사례 분석)

  • Lee, Suk-Yong;Rhim, Hong-Chul;Kim, Ook-Jong;Cho, Hong-Duk;Jeong, Mee-Ra
    • Proceedings of the Korean Institute of Building Construction Conference
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    • pp.15-19
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    • 2008
  • The use of Precast Concrete (PC) stairways is increasing to replace existing Reinforced Concrete (RC) stairways for the faster construction and the better quality control. Among several already developed PC stairway construction methods, RC Core Sequential Construction Method by Using PC Stairways (COSEC) has advantages of 1) allowing core of a building to be built prior to PC stairways so that two different procedures will not interfere with each other, and 2) having a newly developed joint connection with the core so that the RC core and PC stairways can be easily put together. In this paper, cases of several construction sites with the PC stairways method are analyzed. The elements of the developed method are described for further application and improvement.

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A study on the success factor of Quality Management in bath-tub & washbowl (위생기기 제조기업의 품질경영 성공요인에 관한 연구)

  • Hwang Kyoo-Ill;Lee Jae-ha
    • Proceedings of the Korean Society for Quality Management Conference
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    • pp.484-489
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    • 2004
  • The purpose of this study is to examine the success factor of Quality Management (QM) in the manufacturing conditions aspect of medium and small-sized sanitary enterprise. The requisite for manufacturing factors are classified into manufacturing human factors (the number of production employee, training and teaching, discuss on quality, manufacture expertness, etc.), manufacturing facility factors (coating, hardening, and molding equipment), manufacturing core component factors (temperature and viscosity, line, surface). And the indicator of quality outcomes are measured by reorder and recommendation to others.

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Thermal-Hydraulic Test Facilities and Some Test Results of Integrated Heating Reactors

  • Jia, Haijun;Wu, Shaorong;Jiang, Shengyao
    • Proceedings of the Korean Nuclear Society Conference
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    • pp.211-216
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    • 1996
  • Since the middle of the eighties of this century a research program both for heating reactor and investigation of heating reactor thermal-hydraulics has been carried out in Institute of Nuclear Energy Technology(INET) of Tsinghua university in China. This kind of heating reactor is a light water cooled and integrated natural circulation reactor with low system pressure and low quality at the exit of core. Because of relatively long riser and low system pressure. a little change of the quality at the exit of the core will result in a relatively large variation of void fraction in the riser. Two full scale test loops. HRTL-5 and HRTL-200 simulating the HR-5 and HR-200 heating reactors in geometry and operation parameters respectively, and some test results from the HRTL-200 test facility are shown in this paper. The range of studied system pressure is from 1.0MPa to 4.0MPa, the largest heat flux is about 50 W/cm2, and the quality at the exit of test section is less than 5%.

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The Continuous Improvement, Innovation and Learning Concept Embedded in MBNQA Award (MBNQA상에 내포된 지속적 개선, 혁신과 학습 개념)

  • Chung, Kyu-Suk;Kang, Young-Tai
    • Journal of the Korean Society for Quality Management
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    • v.35 no.1
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    • pp.73-80
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    • 2007
  • The learning, which is a view extended from and replaces the concept of continuous improvement, has become the very core concept in Malcolm Baldrige National Quality Award. The most potent one among 11 core values in MBNQA Model is 'organizational and personal learning'. Learning also plays a critical role to get the good scores for 6 categories except results category among 7 categories of MBNQA Model. But the concept of learning often has been overlooked by the people who are interested in the MB award or TQM. This paper reviews and analyzes the concept of learning in the MB criteria since it first appears in 1993 to enlighten the importance of learning.

Microbial composition in different gut locations of weaning piglets receiving antibiotics

  • Li, Kaifeng;Xiao, Yingping;Chen, Jiucheng;Chen, Jinggang;He, Xiangxiang;Yang, Hua
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.1
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    • pp.78-84
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    • 2017
  • Objective: The aim of this study was to examine shifts in the composition of the bacterial population in the intestinal tracts (ITs) of weaning piglets by antibiotic treatment using high-throughput sequencing. Methods: Sixty 28-d-old weaning piglets were randomly divided into two treatment groups. The Control group was treated with a basal diet without antibiotics. The Antibiotic group's basal diet contained colistin sulfate at a concentration of 20 g per ton and bacitracin zinc at a concentration of 40 g per ton. All of the pigs were fed for 28 days. Then, three pigs were killed, and the luminal contents of the jejunum, ileum, cecum, and colon were collected for DNA extraction and high-throughput sequencing. Results: The results showed that the average daily weight gain of the antibiotic group was significantly greater (p<0.05), and the incidence of diarrhea lower (p>0.05), than the control group. A total of 812,607 valid reads were generated. Thirty-eight operational taxonomic units (OTUs) that were found in all of the samples were defined as core OTUs. Twenty-one phyla were identified, and approximately 90% of the classifiable sequences belonged to the phylum Firmicutes. Forty-two classes were identified. Of the 232 genera identified, nine genera were identified as the core gut microbiome because they existed in all of the tracts. The proportion of the nine core bacteria varied at the different tract sites. A heat map was used to understand how the numbers of the abundant genera shifted between the two treatment groups. Conclusion: At different tract sites the relative abundance of gut microbiota was different. Antibiotics could cause shifts in the microorganism composition and affect the composition of gut microbiota in the different tracts of weaning piglets.

A Study of Matrix Model for Core Quality Measurement based on the Structure and Function Diagnosis of IoT Networks (구조 및 기능 진단을 토대로 한 IoT네트워크 핵심품질 매트릭스 모델 연구)

  • Noh, SiChoon;Kim, Jeom Goo
    • Convergence Security Journal
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    • v.14 no.7
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    • pp.45-51
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    • 2014
  • The most important point in the QoS management system to ensure the quality of the IoT system design goal is quality measurement system and the quality evaluation system. This research study is a matrix model for the IoT based on key quality measures by diagnosis system structure and function. Developing for the quality metrics measured Internet of Things environment will provide the foundation for the Internet of Things quality measurement/analysis. IoT matrix system for quality evaluation is a method to describe the functional requirements and the quality requirements in a single unified table for quality estimation performed. Comprehensive functional requirements and quality requirements by assessing the association can improve the reliability and usability evaluation. When applying the proposed method IoT quality can be improved while reducing the QoS signaling, the processing, the basis for more efficient quality assurances as a whole.