• 보건행정학회지
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• 제22권4호
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• pp.597-627
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• 2012

As misalignments among images, identity, and legitimacy of health professionals and institutions have been on the rise, CEOs of health care organizations have been required to enhance organizational accountability. Despite the accumulation of literature on the conceptual discussions of accountability, only a few studies empirically investigated key barriers to accountability and its facilitators. To identify perception on accountability with key barriers and facilitators of organizational accountability, a semi-structured interview with 11 CEOs of Korean hospitals was conducted. A short survey was taken to get quantitative data on CEO's perception on organizational accountability. To CEOs, accountability was very complex and unfamiliar concept, but understood as physician's code of ethics by nature and basic principle of hospital management. CEOs thought accountability could be improved through ethical leadership, financial stability and learning climate of hospitals. Distrust of the government, which failed to provide economic incentives for hospitals to increase accountability activities, was emphasized as a serious barrier to hospital accountability. There was consensus among hospital CEOs as to the importance of accountability in management. However, there were concerns that, without policy instruments to motivate hospitals toward increasing community benefits as well as collective efforts among health professionals to rebuild moral climate for being accountable, greater accountability would not be achieved in hospitals.

• 한국세라믹학회지
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• 제53권3호
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• pp.306-311
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• 2016

Li-air batteries have received much attention due to their superior theoretical energy density. However, their sluggish kinetics on the cathode side is considered the main barrier to high performance. The rational design of electrode catalysts with high activity is therefore an important challenge. To solve this issue, we performed density functional theory (DFT) calculations to analyze the adsorption behavior of the $LiO_2$ molecule, which is considered to be a key intermediate in both the Li-oxygen reduction reaction (ORR) and the evolution reaction (OER). Specifically, to use the activity descriptor approach, the $LiO_2$ adsorption energy, which has previously been demonstrated to be a reliable descriptor of the cathode reaction in Li-air batteries, was calculated on $LaB_{1-x}B^{\prime}_xO_3$(001) (B, B' = Mn, Fe, Co, and Ni, x = 0.0, 0.5). Our fast screening results showed that $LaMnO_3$, $LaMn_{0.5}Fe_{0.5}O_3$, or $LaFeO_3$ would be good candidate catalysts. We believe that our results will provide a way to more efficiently develop new cathode materials for Li-air batteries.

• 항공우주기술
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• 제13권2호
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• pp.150-159
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• 2014

본 연구에서는 액체산소/케로신 추진 로켓 엔진 연소장치의 국내 개발에 있어서의 전산유체역학 응용 사례를 간략히 소개하였다. 추진제 공급부에 대한 다차원 유동 해석을 통해 유동 균일성을 확인하고 및 압력 손실을 예측할 수 있으며, 개념 설계 단계에서 추진제 매니폴드 형상 설계안을 비교/선택할 수 있다. 다분야 연소/냉각 성능 통합 해석을 통해 로켓 엔진 연소기의 연료 막냉각 및 열차폐 코팅 조건 등 연소/냉각 성능 관련 설계 문제 해결에 필요한 주요 정보를 도출할 수 있다. 향후 분사면 근처에서의 추진제 혼합 및 연소특성을 파악할 수 있는 해석 모델/기법을 개발할 필요가 있다.

• 기본간호학회지
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• 제22권2호
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• pp.198-206
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• 2015

Purpose: Although previous studies reported that actual application of research findings into the clinical setting was still poor, research utilization is a major component for implementation of Evidence-based Nursing Practice (EBNP). This study was conducted to identify the barriers to research utilization in clinical nurses. Methods: A descriptive survey design was used. Participants were 392 clinical nurses who were interviewed using a structured questionnaire. Results: Priority factors of barriers were setting, communication, research, and nurses. Five of the top 10 barriers were related to 'setting.' The first barrier was difficulty in the comprehension of statistical analyses. Nurses who worked in secondary hospitals and regularly read research articles perceived significantly lower barriers to research utilization compared with other nurses. There were statistically differences in research utilization among the groups by level of searching skills related to research documents and degree of understanding of EBNP. Conclusion: The study findings identified the top barriers to research utilization and key factors for nursing administrators and educators to consider in developing strategies to facilitate the utilization of research findings in clinical settings.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.426.1-426.1
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• 2016

We report high work function Aluminum doped zinc oxide (AZO) films as insertion layer as a function of O2 flow rate between transparent conducting oxides (TCO) and hydrogenated amorphous silicon oxide (a-SiOx:H) layer to improve open circuit voltage (Voc) and fill factor (FF) for high efficiency thin film solar cell. However, amorphous silicon (a-Si:H) solar cells exhibit poor fill factors due to a Schottky barrier like impedance at the interface between a-SiOx:H windows and TCO. The impedance is caused by an increasing mismatch between the work function of TCO and that of p-type a-SiOx:H. In this study, we report on the silicon thin film solar cell by using as insertion layer of O2 reactive AZO films between TCO and p-type a-SiOx:H. Significant efficiency enhancement was demonstrated by using high work-function layers (4.95 eV at O2=2 sccm) for engineering the work function at the key interfaces to raise FF as well as Voc. Therefore, we can be obtained the conversion efficiency of 7 % at 13mA/cm2 of the current density (Jsc) and 63.35 % of FF.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1264-1273
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• 2010

Soil-bentonite cutoff walls are widely recognized to be the effective barrier for containment of wastes and groundwater. Bentonite cake is usually found remaining on the trench surface due to the use of bentonite slurry during the excavation for the cutoff wall construction. Defects also inevitably take place due to the inappropriate construction procedures or improperly mixed soil-bentonite backfill. The defects include insufficient keys and windows in the soilbentonite cutoff wall. In this study, the performance of the soil-bentonite cutoff wall is evaluated based on the flow rates through the wall. Three-dimensional numerical models were applied to simulate the groundwater flow through the soil-bentonite cutoff walls of typical geometries with consideration of the defects and bentonite cake. Results of the simulations showed that the bentonite cake has no effect in the insufficient key cases. In the keyed wall cases, the bentonite cake with very low hydraulic conductivity significantly impedes the flow of groundwater through the wall. The presence of the bentonite cake not only compromises the window defect but also renders the wall construction more effective in blocking the groundwater flow. These findings show the significance of the bentonite cake in a soil-bentonite cutoff wall construction.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.744-744
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• 2009

The development of safe and suitable hydrogen storage materials is one of key issues for commercializing hydrogen as an energy carrier. Carbon based materials have been investigated for many years to store hydrogen by the adsorption of the gas on the surface of the carbon structure. Recently, it is reported that carbon nitride nanobells have high hydrogen storage capacity since the nitrogen atom plays an important role on attracting hydrogen molecules. Here we report carbon nitride microporous spheres (CNMS) which have the maximum surface area of 995.3 $m^2/g$. Melamine-Formaldehyde resin is the source of carbon and nitrogen in CNMS. Most of the CNMS pores have diameters in the range of 6 to 8 A which could give a penetration energy barrier to a certain molecule. In addition, the maximum hydrogen storage capacities of carbon nitride spheres are 1.9 wt% under 77 K and 1 atm.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.278-281
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• 2009

Proton exchange membrane is the key material for proton exchange membrane fuel cells (PEMFC). Currently widely-used perfluorosulfonic acid membranes have some disadvantages, such as low thermal stability, easy swelling, excessive crossover of methanol and high price etc. Other membranes, including sulfonated polymer, radiation grafted membranes, organic-inorganic hybrids and acid-base blends, do not satisfy the criteria for PEMFC, which set a barrier to the development and commercialization of PEMFC. Pore-filling type proton exchange membrane is a new proton exchange membrane, which is formed by filling porous substrate with electrolytes. Compared with traditional perfluorosulfonic acid membranes, pore-filling type proton exchange membranes have many advantages, such as non- swelling, low methanol permeation, high proton conductivity, low cost and a wide range of materials to choose. In this research, preparation methodology of pore-filling membranes by particularly using all hydrocarbon polymers and fuel cell performances with the membranes are evaluated.

• 한국도서관정보학회지
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• 제41권1호
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• pp.29-49
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• 2010

디지털 세계에서의 지식정보의 접근성은 개인, 직업, 국가의 발전을 위한 핵심인자로 부상하고 있다. 그러나 세계 출판물 가운데 인쇄물을 이용할 수 없는 사람을 위한 대체자료는 5%에 불과하다. 장애인은 자신들이 필요로 하거나 읽고 싶은 자료에 접근할 수 없는 문제를 최대의 장애로 인식하고 있다. 이에 이 연구는 주요 국가(미국, 캐나다, 영국, 스웨덴, 일본, 한국)의 장애인을 위한 대체자료 개발정책(주체와 역할, 재정과 지원, 생산과 배포시스템 등)을 정밀 분석하였다. 그리고 이 예비연구의 결과는 국내에서 대체자료를 생산 배포하기 위한 국가적 계획과 역할모형의 개발을 위한 배경정보로 활용될 것이다.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 KSAM Annual Meeting
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• pp.14-16
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• 2001

The outer membrane (OM) of gram-negative bacteria acts as an effective permeability barrier against noxious agents including several antibiotics and organic solvents, and lipopolysaccharide (LPS) is the key molecule for this function. Outer membrane modified mutants (Ml-166, M2-42, M3-21) of E. coli DH5$\alpha$/pBSl were selected through a mutation using EMS (ethyl-methane-sulfonate). Among the selected mutants, M3-21 was twice as sensitive as LumisTo $x^{ }$ to benzene and M2-41 was 8 times as sensitive as LumisTo $x^{ }$ to toluene. To identify the structural change in the membrane by mutation, the relative cell surface hydrophobicities and the absorption of the crystal violet to the organisms were measured. All the mutants absorbed more crystal violet than their parent and the absorption of crystal violet increased in cell walls as carbohydrate of lipopolysaccharide decreased. When the cell surface hydrophobicities of DH5/pBSl and its mutants were measured by the BATH, the hydrophobicities of mutants increased compared to their parent in several organic solvents. The difference of lipopolysaccharide between DH5/pBSl and its mutants was identified by various ways such as the SDS-PAGE gel, the screening of LPS molecular weights, the mass spectrometry, and MALDI-TOF.F.