• 제목/요약/키워드: Self-reaction

검색결과 739건 처리시간 0.028초

BSCCO Superconducting Powder by SHS

  • Soh, Dea-Wha;Cho, Yong-Joon;Korobova, N.
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.99-102
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    • 2002
  • The BSCCO superconductor materials of using Self-propagating High-temperature Synthesis (SHS) were studied. Mechano-chemical activation - as a pre-treatment of the reactants mixture - strongly influences the kinetic parameters, the reaction mechanism, and the composition and structure of the final product. In this paper as an effort for fabricating the SHSed BSCCO superconductor powder SHS method was considered to application in the synthesis of superconducting materials.

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자동화된 포집과 HPLC 분석 자동시스템을 이용한 과산화수소의 측정 (Measuremets of Hydroperoxides with Automated Collection and HPLC Analysis)

  • 김영미;배성연;이미혜
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2002년도 추계학술대회 논문집
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    • pp.237-238
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    • 2002
  • 과산화수소는 광화학적 이차 생성물질이며 대기의 산화상태를 알려주는 지시자의 역할을 한다. H2O2 는 O3의 광분해로 시작되는 광화학 반응 중 HO2 radical 의 self reaction(HO2+ HO2+M$\longrightarrow$H2O2+M)으로 주로 생성된다(Lee,2000). 대기 내 수명이 1-2일인 과산화수소를 측정하므로써 오존의 대표적인 전구물질인 NOx와 VOC를 산화시키는 OH, HO2 라디칼의 농도를 예측할 수 있고 궁극적으로 오존을 저감하는 대책을 세우는데 필요한 요인으로 사용된다. (중략)

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마그네트론 스퍼터링법을 이용한 Al-Ni Nano-foils의 형성 기구 및 미세구조 특성

  • 유광춘;이원범;조용기;유세훈;김형순
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2013년도 춘계학술대회 논문집
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    • pp.175-175
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    • 2013
  • Al-Ni nano-foil은 상온에서 외부 방전 및 촉발에 따라 급속한 자기 발열 반응이 일어나는 특성을 보이며, 외부 촉발을 통해 상온에서 온도를 높일 수 없는 접합이나 마이크로 수준의 미세 접합이 가능한 접합재료로서 현재 상당한 기대가치를 갖고 있는 재료이다. 코팅기술로서 sputtering법을 이용하여 Al-Ni 다층막의 nano-foil를 제조하여 Al-Ni 혼합 비율 및 Bi-layer 수에 따른 self-propagating reaction에 대해 조사하였다.

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Conformational Study of Pseudo-Proline Dipeptide in the Gas Phase and Solutions

  • Park, Hae-Sook;Kang, Young-Kee
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.158.1-158.1
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    • 2003
  • We report here the results on N-acetyl-N"-methylamide of oxazolidine (Ac-Oxa-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level of theory with the 6-31 +G(d) basis set. The displacement of the $\gamma$-$CH_2$ group in proline ring by oxygen atom has affected the structure of proline, cis-trans equilibrium, and rotational barrier. The up-puckered structure is found to be prevalent for the trans conformers of the Oxa amide. (omitted)

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Necrotizing Sialometaplasia: A Diagnostic Puzzle for Clinicians

  • Jeong, Bo-Young;Park, Hee-Kyung
    • Journal of Oral Medicine and Pain
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    • 제47권2호
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    • pp.102-106
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    • 2022
  • Necrotizing sialometaplasia is a rare, benign, self-limiting inflammatory process, with most cases occurring in the palatal region. Although the pathophysiology of this condition remains unknown, it has generally been considered an ischemic reaction involving the minor salivary glands. Due to its clinical and histologic similarities to malignant salivary gland tumor, diagnostic biopsy is required. Careful monitoring is also recommended, and clinicians should provide sufficient information for pathologists to ensure the histologic diagnosis.

Renzulli 수학 영재 교수-학습 모형 적용에 관한 연구

  • 남영만;박동암
    • East Asian mathematical journal
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    • 제25권3호
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    • pp.379-397
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    • 2009
  • In this paper we apply to Renzulli's Teaching and Learning models for mathematically gifted students based on the gifted science education center in university. Gifted students were very positive reaction in solving problems creatively using this program, and they were challenging and very confident performing new tasks. They reacted variously in debates with their classmates, in self-initiative studying. So more positive changes are needed for the activities using the gifted learning-teaching program to let each student have full use of his or her possibility and potential.

직무긴장 모형을 이용한 치과위생사의 직무스트레스와 반응 (Job stress and reaction of dental hygienist by using the job strain model)

  • 최미숙;안권숙
    • 한국치위생학회지
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    • 제10권4호
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    • pp.595-605
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    • 2010
  • Objectives : A precedent research has documented that occupational stress is closely associated with increased the risk of fatigue and decreased in job satisfaction. This study was conducted in an effort to assess the relationship of occupational stress to self-perceived fatigue and job satisfaction by using job strain model. Methods : The number of respondents was 122 dental hygienist who work in dental clinic and period of the investigation was July 2009 through september 2009. A structured questionnaire was employed to evaluate the participants' sociodemographics, job-related factors, health-related behaviors, occupational stress, job satisfaction and self-perceived fatigue. Occupational stress and self-perceived fatigue were assessed using the Korean Occupational Stress Scale-Short form (KOSS-SF) and the Multidimensional Fatigue Scale (MFS), respectively. Results : In job strain model, the ratio of Q2(High Strain Job) group that more susceptible to disease by stress than other group was 16% and the proportion of high fatigue group(Q3, Q4 group) and low job satisfaction group(Q3, Q4 group) was 48%, 45% respectively. In logistic regression analyses, a High Strain Job group was associated with higher odds of react factor(fatigue, job satisfaction) and the odds was down by 3.3%~7.5% after adjustment for age, smoking, alcohol drinking, regular exercise. So the effective strategy for fatigue, job satisfaction reduction for dental hygienist requires additional program focusing on innovated work environment that provide a enough leisure time and exercise program considering the personality traits. Conclusions : The results of this study suggest that occupational stress is a determinant predictor of self perceived fatigue and job satisfaction. Thus, a stress management program for the reduction of occupational stress, and the promotion of dental hygienist impact assessment health and quality of life is strongly recommended.

미생물(微生物)을 이용한 자기수부성(自己修復性) 스마트 콘크리트 개발에 관한 기초연구 (A Study on the Development of Self-Repairing Smart Concrete Using Microorganism)

  • 김화중;천우영;고관호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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    • pp.441-444
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    • 2008
  • 본 연구는 콘크리트 구조물의 유지관리 및 보전활동의 절력화(節力化)와 장기 수명화를 목적으로 콘크리트에 발생하는 미세한 균열에도 수시의 점검이 가능해지도록 콘크리트 그 자체에 자기 수복 기능을 부여하는 것에 관한 연구이다. 현재 국외 전문 학술지를 통해 제안되고 있는 자기 수복 콘크리트를 조사해 각각의 특징이나 앞으로의 해결과제에 대해 고찰하였으며, 지금까지와는 완전히 다른 방법으로 박테리아의 생화학 반응을 이용한 자기 수복 콘크리트 개발에 관한 기초연구로서, 생물이 자신의 몸 내외에 광물(Bio-mineral)을 만들어 내는 작용. 즉, 생체 광물 형성 작용(Bio-mineralization)을 이용하여 콘크리트의 개질(改質) 및 성능향상을 목적으로 한 새로운 가능성에 대한 내용이다. 여기에서는 Bacillus pasteurii등의 박테리아가 탄산칼슘을 석출시키는 Bio-mineralization을 이용한다고 하는 새로운 발상으로부터의 콘크리트 역학적 성능 및 내구성의 향상, 균열의 보수등의 가능성에 대한 검토를 소개하고, 기초적 실험을 통해 향후 행해져야 할 연구의 방향성이나 자기 수복 콘크리트의 발전 가능성에 대해 연구하였다.

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점진적 근육이완요법이 청소년 운동선수의 행동상태와 정서반응에 미치는 효과* (Effects of Progressive Muscle Relaxation on Behavioral States and Emotional Reactions of Adolescent Athletes)

  • 박선남
    • Child Health Nursing Research
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    • 제7권3호
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    • pp.383-396
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    • 2001
  • This study was designed to investigate the effects of the progressive muscle relaxation on behavioral states and emotional reactions of adolescent athletes. The participants were 167 adolescent male soccer players aged between 12 and 18 who were junior or high school students in Seoul. Ninety-three of them were assigned to the experimental group, while seventy-four to the control group. The experimental group was treated by 10 sessions (20 min./session) of Jacobson's progressive muscle relaxation for two weeks, while the control group was not treated. The self and observer reported behavioral states, general stress by visual analogue scale, physical symptoms of stress, athletic stress, state anxiety, depression, self-esteem were measured before and after two weeks of the progressive muscle relaxation. The results were as follows ; 1. The self and observer reported behavioral states were significantly decreased in the experimental group compared with the control group. 2. The general stress and the gastrointestinal symptoms of stress were significantly decreased in the experimental group compared with the control group. No significant difference on athletic stress was found between the two groups. The depression and the state anxiety were significantly decreased in the experimental group compared with the control group. The self-esteem was significantly increased in the experimental group compared with the control group. 3. The influential factors on behavioral state of adolescent male athlete were depression and state anxiety. The accelerating factor on behavioral state change after the progressive muscle relaxation was state anxiety. These results are suggested that the progressive muscle relaxation could be effective in stabilizing behavioral state, decreasing general stress, gastrointestinal symptoms of stress, depression, state anxiety, in increasing self-esteem of adolescent male athletes. And the behavioral state change after the progressive muscle relaxation was influenced by state anxiety.

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자기 유사한 트래픽을 이용한 ATM 스위치의 ABR 혼잡제어 알고리즘의 성능분석 (Performance Analysis for ABR Congestion Control Algorithm of ATM Switch using Self-Similar Traffic)

  • 진성호;임재홍
    • 정보처리학회논문지C
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    • 제10C권1호
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    • pp.51-60
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    • 2003
  • 네트워크를 설계하고 서비스를 구현하는데 있어서 중요한 변수중의 하나는 트래픽의 특성을 파악하는 것이나 기존의 트래픽 예측과 분석은 포아송(Poisson) 또는 마코비안(Markovian)을 기본으로 하는 모델을 사용하였다. LAN, WAN 및 VBR(Variable Bit Rate) 트래픽 특성에 관한 최근의 실험적 연구들은 기존의 포아송 가정에 의한 모델들이 네트워크 트래픽의 장기간 의존성 및 자기 유사한 특성들을 과소평가 함으로써 실제 트래픽의 특성을 제대로 나타낼 수 없다는 것을 지적해 왔고 최근 실제 트래픽과 유사한 모델로서 자기 유사한 특성을 이용한 접근법이 대두되고 있다. 따라서, 본 논문에서는 실제 트래픽과 유사한 자기 유사 데이터 트래픽을 백그라운드 부하로 발생시켜 기존의 ABR (Available Bit Rate) 혼잡제어 알고리즘 중 대표적인 EFCI(Explicit Forward Congestion Indication), EPRCA(Enhanced Proportional Rate Control Algorithm), ERICA(Explicit Rate Indication for Congestion Avoidance), NIST(National Institute of Standards and Technology) 스위치 알고리즘이 버스트한 트래픽에 대해 효율적으로 반응하는지를 ACR(Allowed Cell Rate), 버퍼 사용율, 셀 폐기율, 전송효율 등으로 나누어 분석을 하였다.