• 제목/요약/키워드: enrichment

검색결과 1,855건 처리시간 0.024초

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

  • 유병훈;황철홍;한지웅;이창언
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
    • /
    • pp.169-174
    • /
    • 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.

  • PDF

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

  • 이경희;황기철
    • 디지털융복합연구
    • /
    • 제12권8호
    • /
    • pp.423-430
    • /
    • 2014
  • 본 연구의 목적은 뇌졸중 동물 실험 모델에서 환경 강화는 기능 회복을 향상 시키고 이로 인하여 뇌에 형태학적, 생화학과 행동에서 특징적인 변화와 그 효과들을 소개하고, 뇌졸중 환자에 환경 강화의 적용은 재활치료 및 작업치료를 포함한 다양 치료와 전 임상 실험의 중요성을 설명하고자 한다. 이 종설 논문에서는 주로 뇌졸중 동물 실험 모델에서 환경 강화로 인한 기능적 회복에 대한 효과와 신경 친화성 물질, 특정 단백질의 발현 및 임상 적용 사례 등의 연구 결과들을 소개하였다. 마지막으로 임상에서 뇌졸중 환자에게 환경 강화의 적용 가능성과 작업치료 및 재활치료의 관점에서 설명하였다.

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

  • 이자혜;김민경
    • 한국수학교육학회지시리즈A:수학교육
    • /
    • 제55권2호
    • /
    • pp.209-232
    • /
    • 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
    • /
    • 제45권2호
    • /
    • pp.120-125
    • /
    • 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/.

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

  • 이기용;남태형;유현석;최동수
    • 한국연소학회:학술대회논문집
    • /
    • 한국연소학회 2000년도 제21회 KOSCO SYMPOSIUM 논문집
    • /
    • pp.77-82
    • /
    • 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.

  • PDF

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
    • /
    • 제17권1호
    • /
    • pp.110-115
    • /
    • 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.

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

  • 이은영;장진경
    • Human Ecology Research
    • /
    • 제54권2호
    • /
    • pp.165-180
    • /
    • 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.

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

  • 이영준;서영민
    • 컴퓨터교육학회논문지
    • /
    • 제15권5호
    • /
    • pp.33-41
    • /
    • 2012
  • 초등학교에서는 폭넓은 체험과 경험을 통하여 자신의 소질과 능력을 찾아내는 기회를 제공하여 주어야 한다. 그러나 현재 우리나라의 초등학교 정보교육은 전체 학생들을 대상으로 하지 않고 일부 학생들에게 편중되어 있는 실정이다. 때문에 수학이나 과학 교과에 비하여, 정보 분야에 재능을 가지고 있는 학생들을 발견할 기회가 매우 제한되어 있는 구조적인 문제를 안고 있다. 본 연구에서는 학교전체 심화학습 모형에 기반한 로봇교육 프로그램을 개발하였고, 이를 통하여 현재의 초등학교 정보교육이 가지는 문제점을 극복하고자 하였다. 심화학습 위원회 구성과 교육과정 수정을 통하여 정규교육에서 전체 학생들을 대상으로 로봇교육 실행 가능성을 도모하였다. 그 결과 학교전체 심화학습 모형에 기반한 로봇 학습은 창의적 잠재력 향상에 도움이 되는 것으로 나타났다.

  • PDF

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
    • /
    • 제48권3호
    • /
    • pp.778-784
    • /
    • 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.

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

  • 송주민;김진상
    • The Journal of Korean Physical Therapy
    • /
    • 제16권2호
    • /
    • pp.72-89
    • /
    • 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.

  • PDF