• 제목/요약/키워드: ICISS

검색결과 19건 처리시간 0.022초

비행시간형 직층돌 이온산란 분광법을 사용한 MgO(001) 면에 성장된 TiO막의 구조해석 (Structure Analysis of TiO Film on the MgO(001) Surface by Time-Of-Flight Impact-Collision Ion Scattering Spectroscopy)

  • 황연;이태근;박병규
    • 한국결정학회지
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    • 제13권2호
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    • pp.57-62
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    • 2002
  • MgO(001)면 위에 Ti 금속을 증착시킨 후 400℃에서 산소에 노출시킴으로써 헤테로 에피탁시 TiO 막을 성장시켰다. 성장된 TiO막의 원자구조를 비행시간형 직충돌 이온산란 분광법을 사용하여 해석하였다. MgO(001)면에 성장된 에피탁시 TiO막은 다음과 같은 구조를 갖고 있음이 밝혀졌다. Ti및 O 원자가 MgO 원자의 위에 위치하여 면내방향의 격자상수는 MgO의 격자상수와 일치하고, TiO막의 표면은 3차원적 섬 형상이 없는 평활한 구조를 가지고 있다.

Atomic Structure Analysis of BaO Layers on the Si(100) Surface by Impact-Collision ion Scattering Spectroscopy

  • Hwang, Yeon
    • 한국결정학회지
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    • 제17권2호
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    • pp.51-54
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    • 2006
  • BaO layers were formed on the Si(100) surface by thermal evaporation of barium metal with simultaneous oxidation. The atomic structure of BaO layers at the initial stage of the deposition was investigated by the scattering intensity variation of $He^+$ions on time-of-flight (TOF) impact-collision ion scattering (ICISS). The results show that several number of BaO layers are formed on the Si(100) surface with the lattice parameter of bulk phase, and the occupation of oxygen atoms of the BaO layers is on-top site of silicon atoms.

비행시간형 직충돌 이온산란 분광법을 사용한 TiC(001)면에 성장된 MgO막의 구조해석 (Structure of epitaxial MgO layers on TiC(001) studied by time-of-flight impact-collision ion scattering spectroscopy)

  • 황연;소다 류타로
    • 한국진공학회지
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    • 제6권3호
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    • pp.181-186
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    • 1997
  • TiC(001) 면위에 Mg금속을 증착시킨 후 상온에서 산소를 노출시키는 방법으로 hetero-epitaxial MgO막을 성장시켰으며, 성장된 MgO epitaxial막의 구조를 비행시간형 직 충돌 이온산란분광법을 사용하여 해석하였다. MgO막은 산화 직후 무질서한 배열을 갖으나, 약 $300^{\circ}C$의 가열에 의해서 1$\times$1구조로 전환된다. TiC(001) 위에 성장된 MgO막은 다음과 같은 구조를 갖고 있음이 밝혀졌다. Mg 및 O원자는 TiC의 on-top site에 위치하고, 면내방 향의 격자상수는 TiC의 격자상수와 일치하며, MgO막의 대부분은 2층 이내의 원자층으로 구성되어 있다.

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응급의료센터 성과 평가 기준개발과 적용 (Performance Evaluation of Emergency Medical Center)

  • 강철환;김윤;이평수;권영대;김창엽;신영수
    • Journal of Preventive Medicine and Public Health
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    • 제30권4호
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    • pp.884-892
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    • 1997
  • Currently, there are 100 community emergency centers which expect to provide professional emergency care like Level 1 trauma centers in U.S.A. To evaluate perforance of emergency centers, most studies have been widely adopted death rate based methods such as Trauma and Injury Severity Score(TRISS) and A Severity Characterization of Trauma(ASCOT). However, these methods are only applicable in situation where registration process of trauma patients is well established. Therefore, an alternative method should be applied to evaluate performance of emergency centers in Korea which does not have well-developed registration scheme. This study aims to develop new performance measures which are applicable to Korea and evaluate performance of 35 community emergency centers through new measures. The new measures are included that 'W-statistic' ; death rate calculated on the basis of International Classification based Injury Severity Score(ICISS), and 'the degree of severity' ; rate of severe trauma patients of each emergency medical centers. The study results can be summarized as follows. First, about 34% of sample emergency centers show they provide proper care in terms of their function. Second, tertiary hospitals, university hospitals, and hospitals located in Seoul show higher severity degree of patients and lower severity-adjusted death rate.

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직충돌 이온산란 분광법(ICISS)에 의한 고체 표면구조의 해석(1): 기본 원리 (Structure Analysis of Solid Surfaces by Impact Collision Ion Scattering Spectroscopy (1): Basic Principles)

  • 황연
    • 한국결정학회지
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    • 제17권2호
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    • pp.60-65
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    • 2006
  • 표면 및 계면층의 결정구조, 결함구조, 불순물 편석, 표면의 전자 구조, 원자 진동 등과 같은 산화물의 표면물성은 촉매, 센서, 소결, 마찰, 부식 등과 같은 분야에서 그 특성을 좌우한다. 고체 표면의 결정구조 해석 수단으로 저에너지 이온산란 분광법이 유용한 도구로 알려져 있는데, 이 방법의 뛰어난 표면민감성은 표면에서의 효과적인 이온 중성화 과정에 기인한다. $He^+$, $Ne^+$, $Ar^+$ 등과 같은 이온은 Auger 중성화 과정에 의하여 쉽게 중성원자화 되고, 중성화 확율의 타겟에 대한 의존성이 낮기 때문에 이온빔으로서 종종 사용된다. 산란각도를 180$^{\circ}$로 고정하여 산란이온 검출기를 설치한 직충돌 이온산란 분광법의 경우는 산란된 이온의 궤적이 입사궤도와 거의 동일하기 때문에 산란궤적의 계산이 간단해지고, 수 층 깊이의 원자구조의 해석이 가능해진다. 본 고에서는 고체 표면의 원자구조를 실공간에서 해석할 수 있는 직충돌 이온산란 분광법에 대하여 측정의 기본원리, 측정장치, 간단한 분석 예 등에 관하여 기술하고자 하며, 다음 편에서는 복잡한 표면구조를 가지는 반도체 표면에서 직충돌 이온산란분광법의 이용하여 해석한 예를 중심으로 기술하고자 한다.

비행시간형 직충돌 이온산란 분광법을 사용한 TiC(001)면의 Ta편석 연구 (Ta-Segregation on TiC(001) Surface Studied by Time-Of-Flight Impact-Collision Ion Scattering Spectroscopy)

  • 황연;히시타 슌이치;소우다 류타로
    • 한국재료학회지
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    • 제7권7호
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    • pp.559-563
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    • 1997
  • Ta을 2MeV의 에너지로 가속시켜 1x$10^{17}$atoms/$\textrm{cm}^2$의 농도로 TiC(001)면에 이온 주입시킨 후 비행시간형 직충돌이온산란 분광법(time-of-flight impact-collision ion scattering spectroscopy; TOF-ICISS)을 사용하여 TiC(001)면의 Ta표면 편석을 연구하였다. TOF-ICISS는 표면 수층 깊이까지 원자구조를 측정할 수 있는 수법으로, 이온주입된 시편을 1$600^{\circ}C$에서 300sec동안 진공 가열하여 Ta 원자를 편석시킨 후 스펙트럼의 입사각도 의존성을 구함으로써 Ta원자의 편석 위치 및 농도구배를 조사하였다. [110]및 [100]방위에서 Ta과 Ti의 focusing peak가 서로 같은 입사각도에서 나타나며 편석된 Ta원자는 TiC의 Ti-site에 위치한다. Ta원자는 표면 최외층에만 편석되는 것이 아니라 수층에 걸쳐 Ti-site에 자리하고 있으며, Ta 원자의 농도는 표면 최외층에서 내부 층으로 깊어질수록 작아진다. 이온주입시 생성된 표면층의 탄소 격자 결함은 시편 가열시 벌크에 자리하는 탄소가 확산되어 없어진다.다.

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자전거손상 환자의 역학적 특성 (Epidemiological Characteristics of Bicycle-Injured Patients)

  • 남영희;이명선
    • 한국학교ㆍ지역보건교육학회지
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    • 제14권2호
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    • pp.47-57
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    • 2013
  • Backgrounds: According to a high interest in health these days, a bicycle is being highlighted as a means of leisure activity and auxiliary transportation means. Along with an increase in this interest, there is tendency that even the width of bicycle utilization gets diverse and that bicycle accident is also rapidly growing. Purpose: The purpose of this study was to suggest a prevention measure available for reducing occurrence of bicycle accidents by analyzing the Epidemiological characteristics according to age and injury severity in bicycle-injured patients. Methods: This study analyzed 115 materials suitable for this study by examining a medical record of patients, who received the hospitalized treatment owing to bicycle accident from January 1, 2011 to December 31 at one general hospital in S city. Results: The male-and-female ratio of bicycle-injured patients stood at about 7:3. The average age was 38.14(${\pm}21.59$) years old. The largest injury happened in 40-59 years old(31.3%). The averagely hospitalized period was 17.33(${\pm}18.12$) days. Injury severity was the ratio of 2:8 in a mild case versus a serious case. As for drinking and smoking characteristics according to age, the injury occurred the most in between 40 and 59 years old for people with drinking and smoking and in under 19 years for people without drinking and smoking. According to injury severity, the ratio of serious case got higher in the higher age. This was indicated(${\chi}^2$=15.675, p=0.001) to be statistically significant. Conclusion: In this study, a bicycle accident was indicated to have high injury risk in young children, adolescents, and old-age group. Prevention measure and publicity are demanded for reducing injury occurrence such as the prevention education for bicycle accident and wearing protective gear focusing on the ages of corresponding to groups with risk of injury occurrence. In addition, the security of safe movement route is necessarily demanded in order to increase application level as an auxiliary transportation means.

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비행시간형 직충돌 이온산란 분광법을 이용한 Si(100) 면의 구조해석 (Si(100) Surface Structure Studied by Time-Of-Flight Impact-Collision ton Scattering Spectroscopy)

  • 황연;이태근
    • 한국세라믹학회지
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    • 제40권8호
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    • pp.765-769
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    • 2003
  • 2 keV의 저에너지 He$^{+}$ 이온을 사용한 비행시간형 직충돌 이온산란 분광법을 이용하여 Si(100) 표면의 원자구조를 해석하였다. [011] 방위를 따라 이온빔을 입사시키고, 입사 각도에 따른 산란된 이온의 강도를 측정하였다. 20$^{\circ}$, 28$^{\circ}$, 46$^{\circ}$, 63$^{\circ}$, 80$^{\circ}$등의 5가지 입사각도에서 집속 효과가 일어났다. 이 각도를 설명하기 위해 그림자 원뿔을 계산하여 원자의 위치를 모사하였으며, 이 결과는 실험과 잘 일치하였다. 28$^{\circ}$, 46$^{\circ}$, 63$^{\circ}$ 및 80$^{\circ}$에서 일어나는 4개의 집속 효과는 표면 최외층에서 이 합체가 자리하지 않는 {011}면을 따라서 발생한 것이며 벌크 구조가 반영된 결과이다. 그 반면에 이합체를 이루는 원자사이에서 발생한 산란은 20$^{\circ}$에서 집속 효과를 나타내었다.

중증 외상 환자의 입원 결정 지연에 영향을 미치는 요인과 공동진료시스템 (Factors Affecting the Delay of a Decision to Admit Severe Trauma Patients and the Effect of a Multidisciplinary Department System: a Preliminary Study)

  • 강문주;신태건;심민섭;조익준;송형곤
    • Journal of Trauma and Injury
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    • 제23권2호
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    • pp.113-118
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    • 2010
  • Purpose: Prolonged stay in the emergency department (ED), which is closely related with the time interval from the ED visit to a decision to admit, might be associated with poor outcomes for trauma patients and with overcrowding of the ED. Therefore, we examined the factors affecting the delay in the decision to admit severe trauma patients. Also, a multidisciplinary department system was preliminarily evaluated to see if it could reduce the time from triage to the admission decision. Methods: A retrospective observational study was conducted at a tertiary care university hospital without a specialized trauma team or specialized trauma surgeons from January 2009 to March 2010. Severe trauma patients with an International Classification of Disease Based Injury Severity Score (ICISS) below 0.9 were included. A multivariable logistic regression analysis was used to find independent variables associated with a delay in the decision for admission which was defined as the time interval between ED arrival and admission decision exceeded 4 hours. We also simulated the time from triage to the decision for admission by a multidisciplinary department system. Results: A total of 89 patients were enrolled. The average time from triage to the admission decision was $5.2{\pm}7.1$ hours and the average length of the ED stay was $9.0{\pm}11.5$ hours. The rate of decision delay for admission was 31.5%. A multivariable regression analysis revealed that multiple trauma (odds ratio [OR]: 30.6, 95%; confidence interval [CI]: 3.18-294.71), emergency operation (OR: 0.55, 95%; CI: 0.01-0.96), and treatment in the Department of Neurosurgery (OR: 0.07, 95%; CI: 0.01-0.78) were significantly associated with the decision delay. In a simulation based on a multidisciplinary department system, the virtual time from triage to admission decision was $2.1{\pm}1.5$ hours. Conclusion: In the ED, patients with severe trauma, multiple trauma was a significant factor causing a delay in the admission decision. On the other hand, emergency operation and treatment in Department of Neurosurgery were negatively associated with the delay. The simulated time from triage to the decision for admission by a multidisciplinary department system was 3 hours shorter than the real one.