• Title/Summary/Keyword: Self-reaction

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BSCCO Superconducting Powder by SHS

  • Soh, Dea-Wha;Cho, Yong-Joon;Korobova, N.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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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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Measuremets of Hydroperoxides with Automated Collection and HPLC Analysis (자동화된 포집과 HPLC 분석 자동시스템을 이용한 과산화수소의 측정)

  • 김영미;배성연;이미혜
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2002.11a
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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

  • Yu, Gwang-Chun;Lee, Won-Beom;Jo, Yong-Gi;Yu, Se-Hun;Kim, Hyeong-Sun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2013.05a
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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
    • Proceedings of the PSK Conference
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    • 2003.10b
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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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    • v.47 no.2
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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

  • Nam, Young-Man;Park, Dong-Am
    • East Asian mathematical journal
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    • v.25 no.3
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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.

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

  • Choi, Mi-Suk;Ahn, Kwon-Suk
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.4
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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.

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

  • Kim, Wha-Jung;Chun, Woo-Young;Ko, Kwan-Ho
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.441-444
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    • 2008
  • This study was conducted to develop self-repairing ability for concrete so that inspection could be available even in the event of minute cracks, for more economic concrete structure maintenance and longevity. This is a basic attempt to develop self-repairing concrete using the biochemical reaction of bacteria through an innovative method. In this study, the characteristics and problems posed by self-repairing concrete as proposed in international scientific journals were examined, and the potential of new concrete reformation and performance improvement using bio-mineralization was explored. Bio-mineralization, which is an action of creating bio-minerals using an organism, was proposed. A new concept of bacteria such as bacillus pasteurii using bio-mineralization that precipitates calcium carbonate, as well as the possibility of mechanical performance and durability of concrete and repair of cracks, was introduced. Directions for further study through basic experiments and developmental feasibility of self-repairing concrete were also presented.

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

  • Park Sun-Nam
    • Child Health Nursing Research
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    • v.7 no.3
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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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Performance Analysis for ABR Congestion Control Algorithm of ATM Switch using Self-Similar Traffic (자기 유사한 트래픽을 이용한 ATM 스위치의 ABR 혼잡제어 알고리즘의 성능분석)

  • Jin, Sung-Ho;Yim, Jae-Hong
    • The KIPS Transactions:PartC
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    • v.10C no.1
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    • pp.51-60
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    • 2003
  • One of the most important matters in designing network and realizing service, is to grip on the traffic characteristics. Conventional traffic prediction and analysis used the models which based on the Poisson or Markovian. Recently, experimental research on the LAN, WAN and VBR traffic properties have been pointed rut that they weren't able to display actual real traffic specificities because the models based on the Poisson assumption had been underestimated the long range dependency of network traffic and self-similar peculiarities, it has been lately presented that the new approach method using self-similarity characteristics as similar as the real traffic models. Therefore, in this paper, we generated self-similar data traffic like real traffic as background load. On the existing ABR congestion control algorithm, we analyzed by classify into ACR, buffer utilization. cell drop rate, transmission throughput with the representative EFCI, ERICA, EPRCA and NIST twitch algorithm to show the efficient reaction about the burst traffic.