• Title/Summary/Keyword: enrichment

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NOx Formation Characteristics with Oxygen Enrichment in Nonpremixed Counterflow and Coflow Jet Flames (비예혼합 대향류 및 동축 제트화염에서 산소부화에 따른 NOx 생성특성)

  • Yoo, Byung-Hun;Hwang, Chul-Hong;Han, Ji-Woong;Lee, Chang-Eon
    • 한국연소학회:학술대회논문집
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    • 2004.11a
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    • pp.169-174
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    • 2004
  • The NOx emission characteristics with oxygen enrichment in nonpremixed counterflow and coflow jet flame of $CH_4$ fuel have been investigated numerically. A small amount of nitrogen is included in oxygen-enriched combustion, in order to consider the inevitable $N_2$ contamination by air infiltration. The results show that the initial increase of NO with increasing oxygen enrichment is due to increasing temperature and residence time, while its subsequent decrease above 75% oxygen is due to decreasing the consumption rate of nitrogen. When oxygen addition exceeds 30%, Thermal NO gradually becomes the dominant production pathway and Prompt NO becomes negative pathway for net NO production rate. It is also seen that Thermal NO plays an important role in NO reduction when strain rate increase in oxygen-enriched combustion. Finally, the results of EINOx with oxygen enrichment in coflow jet flame show the similar profile with those of conterflow flame. It is confirmed that, with leakage of 1% nitrogen in the oxidizer stream, the corresponding EINOx is eight times of that emitted from regular $CH_4$/Air flame.

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A review of the effects of environmental enrichment on stroke in animal experimental models (뇌졸중 동물 실험 모델에서 환경 강화 효과에 대한 종설)

  • Lee, Kyoung-Hee;Hwang, Ki-Chul
    • Journal of Digital Convergence
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    • v.12 no.8
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    • pp.423-430
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    • 2014
  • The purpose of this article is to present the environmental enrichment(EE) method used to improve the functional recovery and change of brain plastic in animal experimental models of stroke. In animal experimental models of stroke, the environmental enrichment is effective in altering the morphological, biochemical and behavioral characteristics of the brain and thereby improving the functional outcomes. In this review article, we address the effects of EE in achieving a functional recovery in animal experimental models of stroke, thus attempting to describe them in patients with stroke from both occupational and rehabilitation perspectives.

The Development and Application of Posing Open-Ended Problems Program with Renzulli's Enrichment Triad Model for Mathematics-Gifted Elementary Students (초등 수학 영재를 위한 Renzulli의 삼부심화모델 도입 개방형 수학 문제 만들기 프로그램 개발 및 적용)

  • Lee, Ja Hye;Kim, Min Kyeong
    • The Mathematical Education
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    • v.55 no.2
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    • pp.209-232
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    • 2016
  • This study analyzed the process of steps in a program introducing Renzulli's enrichment triad model and various levels of posing open-ended problems of those who participated in the program for mathematics-gifted elementary students. As results, participants showed their abilities of problem posing related to real life in a program introducing Renzulli's enrichment triad model. From eighteen mathematical responses, gifted students were generally outstanding in terms of producing problems that demonstrated high quality completion, communication, and solvability. Amongst these responses from fifteen open-ended problems, all of which showed that the level of students' ability to devise questions was varied in terms of the problems' openness (varied possible outcomes), complexity, and relevance. Meanwhile, some of them didn't show their ability of composing problem with concepts, principle and rules in complex level. In addition, there are high or very high correlations among factors of mathematical problems themselves as well as open-ended problems themselves, and between mathematical problems and open-ended problems. In particular, factors of mathematical problems such as completion, communication, and solvability showed very high correlation with relevance of the problems' openness perspectives.

GoBean: a Java GUI application for visual exploration of GO term enrichments

  • Lee, Sang-Hyuk;Cha, Ji-Young;Kim, Hyeon-Jin;Yu, Ung-Sik
    • BMB Reports
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    • v.45 no.2
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    • pp.120-125
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    • 2012
  • We have developed a biologist-friendly, Java GUI application (GoBean) for GO term enrichment analysis. It was designed to be a comprehensive and flexible GUI tool for GO term enrichment analysis, combining the merits of other programs and incorporating extensive graphic exploration of enrichment results. An intuitive user interface with multiple panels allows for extensive visual scrutiny of analysis results. The program includes many essential and useful features, such as enrichment analysis algorithms, multiple test correction methods, and versatile filtering of enriched GO terms for more focused analyses. A unique graphic interface reflecting the GO tree structure was devised to facilitate comparisons of multiple GO analysis results, which can provide valuable insights for biological interpretation. Additional features to enhance user convenience include built in ID conversion, evidence code-based gene-GO association filtering, set operations of gene lists and enriched GO terms, and user -provided data files. It is available at http://neon.gachon.ac.kr/GoBean/.

The Flame Structure of Freely Propagating $CH_4$/$O_2$/$N_2$ Premixed Flames on Adding Oxygen (자유롭게 전파하는 $CH_4$/$O_2$/$N_2$ 예혼합화염에서 산소부화에 따른 화염구조)

  • Lee, Ki-Yong;Nam, Tae-Hyoung;You, Hyun-Seok;Choi, Dong-Soo
    • 한국연소학회:학술대회논문집
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    • 2000.12a
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    • pp.77-82
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    • 2000
  • Numerical simulations of freely propagating flames burning stoichiometric $CH_4$/$O_2$/$N_2$ mixtures are performed at atmospheric pressure in order to understand the effect of the $O_2$ enrichment level on $CH_4$/Air flame. A chemical kinetic mechanism is employed, the adopted scheme involving 54 gas-phase species and 632 forward reactions. The calculated flame. speeds are compared with the experiments for the flames established at several $O_2$ enrichment level, the results of which is in excellent agreement. As a result of the increased $O_2$ enrichment level from 0.21 to 1, the mole fraction of CO in the burned gas is increased. The flame speed and the temperature in the burned gas are also increased, but the thickness of the flame is severely shrunken in the preheat region.

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Enrichment of Electrochemically Active Bacteria Using a Three-Electrode Electrochemical Cell

  • Yoon, Seok-Min;Choi, Chang-Ho;Kim, Mi-A;Hyun, Moon-Sik;Shin, Sung-Hye;Yi, Dong-Heui;Kim, Hyung-Joon
    • Journal of Microbiology and Biotechnology
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    • v.17 no.1
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    • pp.110-115
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    • 2007
  • Electrochemically active bacteria were successfully enriched in an electrochemical cell using a positively poised working electrode. The positively poised working electrode (+0.7 V vs. Ag/AgCl) was used as an electron acceptor for enrichment and growth of electrochemically active bacteria. When activated sludge and synthetic wastewater were fed to the electrochemical cell, a gradual increase in amperometric current was observed. After a period of time in which the amperometric current was stabilized (generally 8 days), linear correlations between the amperometric signals from the electrochemical cell and added BOD (biochemical oxygen demand) concentrations were established. Cyclic voltammetry of the enriched electrode also showed prominent electrochemical activity. When the enriched electrodes were examined with electron microscopy and confocal scanning laser microscopy, a biofilm on the enriched electrode surface and bacterium-like particles were observed. These experimental results indicate that the electrochemical system in this study is a useful tool for the enrichment of an electrochemically active bacterial consortium and could be used as a novel microbial biosensor.

A Study on the Marital Relationship Enhancement Programs: Focused on Participation Motivation, Education Satisfaction, Positive Behavioral Intention (부부 관계 향상 프로그램에 대한 연구: 참여 동기, 교육 만족도, 긍정적 행동의도를 중심으로)

  • Lee, Eun-Young;Chang, Jin Kyung
    • Human Ecology Research
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    • v.54 no.2
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    • pp.165-180
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    • 2016
  • This study analyzes the correlations of participation motivation, education satisfaction, and positive behavioral intention for participants in marriage enrichment programs. The survey response results for 193 participants in marriage enrichment programs were analyzed with the statistics analysis application IBM SPSS 20.0. The findings of this study are as follows. An examination of relative influence of participation motivation and education satisfaction with the positive behavioral intention of participants in marriage enrichment programs indicated that internal motivation had a positive influence on education satisfaction, external motivation had a negative influence on satisfaction for facility environment and satisfaction with employee service, and motivation had positive influence only on facility environment. An examination of the influence of participation motivation and education satisfaction with the positive behavioral intention of the participants in marriage enrichment programs indicated that internal motivation and external motivation had a high positive influence on positive behavioral intention. However, motivation did not have a significant influence on behavior after participation. In education satisfaction, satisfaction with content, satisfaction with instructor, and satisfaction with employee service had a positive influence on positive behavioral intention, however, satisfaction with facility environment had negative influence on positive behavioral intention.

The Robot Education Program Based on Schoolwide Enrichment Model for Elementary School Students (학교전체 심화학습 모형에 기반한 초등로봇교육 프로그램)

  • Lee, YoungJun;Seo, YoungMin
    • The Journal of Korean Association of Computer Education
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    • v.15 no.5
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    • pp.33-41
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    • 2012
  • Elementary school students should have many opportunities to find their abilities and talents. However, informatics education in Korea does not target the entire elementary school students, opportunities for informatics education are given only to some students. Unlike possibilities to find mathematics gifted students and science gifted students, opportunities to find informatics gifted students are very limited. This study aims to solve current problems through a robot education program based on SEM(Schoolwide Enrichment Model). Using modified curriculum and school enrichment cluster, robot programming education is implemented at the pilot school. The result shows that robot education program based on SEM improved creative potentials of elementary school students.

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Uranium Enrichment Determination Using a New Analysis Code for the U XKα Region: HyperGam-U

  • Kim, Junhyuck;Choi, Hee-Dong;Park, Jongho
    • Nuclear Engineering and Technology
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    • v.48 no.3
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    • pp.778-784
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    • 2016
  • HyperGam-U was recently developed to determine uranium enrichment based on ${\gamma}$- and X-ray spectroscopy analysis. The $XK_{\alpha}$ region of the uranium spectrum contains 13 peaks for $^{235}U$ and $^{238}U$ and is used mainly for analysis. To describe the X-ray peaks, a Lorentzian broadened shape function was used, and methods were developed to reduce the number of fitting parameters for decomposing the strongly overlapping peaks using channel-energy, energy-width, and energy-efficiency calibration functions. For validation, eight certified reference material uranium samples covering uranium enrichments from 1% to 99% were measured using a high-resolution planar high-purity germanium detector and analyzed using the HyperGam-U code. When corrections for the attenuation and true coincidence summing were performed for the detection geometry in this experiment, the goodness of fit was improved by a few percent. The enrichment bias in this study did not exceed 2% compared with the certified values for all measured samples.

The Effect of Balance Training and environmental enrichment on motor performance after Traumatic Cerebellar Injury in the Rat (균형훈련과 환경강화가 외상성 소뇌 손상 흰쥐의 운동 수행력에 미치는 영향)

  • Song Ju-min;Kim Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.16 no.2
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    • pp.72-89
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    • 2004
  • The purposes of this study were to test the effect of balance training and environmental enrichment on motor performance after traumatic cerebellar injury in the rat. Traumatic cerebellar injury was induced by weight drop model and after operation they were housed in individual standard cages for 24 hours. Twenty two Sprague-Dawley rats were randomly assigned into control and experimental groups. The control group was housed in standard cage for 7 days. The experimental group I was housed in standard cage after balance training for 7 days. The experimental group II was housed in environmental enrichment cage after balance training for 7 days. Vestibular drop test and tilting plane test was examined at preoperation, on 1st day after operation and 7th day after operation to the rats. The results of this experiment were as follows: 1. In motor behavioral test, at preoperation and on 1 day after operation, the outcomes were not different among the groups. But on 7th day after operation, the outcomes of group I were better than that in control group, and group II were better than group I. These results suggest that behavioral motor outcome by simultaneously application of balance training and environmental enrichment in traumatic cerebellar injured rats were more improve than that by just balance training.

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