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Splitting of Surface Plasmon Resonance Peaks Under TE- and TM-polarized Illumination

  • Yoon, Su-Jin;Hwang, Jeongwoo;Lee, Myeong-Ju;Kang, Sang-Woo;Kim, Jong-Su;Ku, Zahyun;Urbas, Augustine;Lee, Sang Jun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.296-296
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    • 2014
  • We investigate experimentally and theoretically the splitting of surface plasmon (SP) resonance peaks under TE- and TM-polarized illumination. The SP structure at infrared wavelength is fabricated with a 2-dimensional square periodic array of circular holes penetrating through Au (gold) film. In brief, the processing steps to fabricate the SP structure are as follows. (i) A standard optical lithography was performed to produce to a periodic array of photoresist (PR) circular cylinders. (ii) After the PR pattern, e-beam evaporation was used to deposit a 50-nm thick layer of Au. (iii) A lift-off processing with acetone to remove the PR layer, leading to final structure (pitch, $p=2.2{\mu}m$; aperture size, $d=1.1{\mu}m$) as shown in Fig. 1(a). The transmission is measured using a Nicolet Fourier-transform infrared spectroscopy (FTIR) at the incident angle from $0^{\circ}$ to $36^{\circ}$ with a step of $4^{\circ}$ both in TE and TM polarization. Measured first and second order SP resonances at interface between Au and GaAs exhibit the splitting into two branches under TM-polarized light as shown in Fig. 1(b). However, as the incidence angle under TE polarization is increased, the $1^{st}$ order SP resonance peak blue-shifts slightly while the splitting of $2^{nd}$ order SP resonance peak tends to be larger (not shown here). For the purpose of understanding our experimental results qualitatively, SP resonance peak wavelengths can be calculated from momentum matching condition (black circle depicted in Fig. 2(b)), $k_{sp}=k_{\parallel}{\pm}iG_x{\pm}jG_y$, where $k_{sp}$ is the SP wavevector, $k_{\parallel}$ is the in-plane component of incident light wavevector, i and j are SP coupling order, and G is the grating momentum wavevector. Moreover, for better understanding we performed 3D full field electromagnetic simulations of SP structure using a finite integration technique (CST Microwave Studio). Fig. 1(b) shows an excellent agreement between the experimental, calculated and CST-simulated splitting of SP resonance peaks with various incidence angles under TM-polarized illumination (TE results are not shown here). The simulated z-component electric field (Ez) distribution at incident angle, $4^{\circ}$ and $16^{\circ}$ under TM polarization and at the corresponding SP resonance wavelength is shown in Fig. 1(c). The analysis and comparison of theoretical results with experiment indicates a good agreement of the splitting behavior of the surface plasmon resonance modes at oblique incidence both in TE and TM polarization.

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The Impact of the Introduction of Hydrogen Energy into the Power Sector on the Economy and Energy (전력부문 수소에너지 도입의 경제 및 에너지부문 파급효과)

  • Lee, Sang-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.502-507
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    • 2016
  • The transition from a carbon economy based on fossil fuels to a hydrogen economy is necessary to ensure energy security and to combat climate change. In order to pursue the transition to a hydrogen economy while achieving sustainable economic growth, a preliminary study into the establishment of the necessary infrastructure for the future hydrogen economy needs to be carried out. This study addresses the economic and environmental interactions in a dynamic computable general equilibrium (CGE) model focusing on the economic effects of the introduction of renewable energy into the Korean energy system. Firstly, the introduction of hydrogen results in an increase in the investment in hydrogen production and the reduction of the production cost, ultimately leading to GDP growth. Secondly, the mandatory introduction of renewable energy and associated government subsidies bring about a reduction in total demand. Additionally, the mandatory introduction of hydrogen energy into the power sector helps to reduce CO2 emissions through the transition from a carbon economy-based on fossil energy to a hydrogen economy. This means that hydrogen energy needs to come from non-fossil fuel sources in order for greenhouse gases to be effectively reduced. Therefore, it seems necessary for policy support to be strengthened substantially and for additional studies to be conducted into the production of hydrogen energy from renewable sources.

Factors Influencing Objective Emergency Nursing Performance of Nursing Students on Simulation Practice (시뮬레이션 실습에서 간호학생의 객관적 응급간호 임상수행능력에 영향 미치는 요인)

  • Choi, Eun Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.296-303
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    • 2020
  • This study examined the factors affecting the emergency nursing performance of nursing students during a simulation. The variables related to the simulation were the objective and subjective emergency nursing performance, critical thinking, program outcome, simulation satisfaction, simulation confidence, and simulation immersion. The participants were 92 senior students who provided informed consent with an explanation about attending the study. The general characteristics and simulation-related data were obtained from the students before and after the simulation. An assessor evaluated the objective emergency nursing performance during the simulation and program outcome through a report reviewed after the simulation. Data analysis was performed using the number, percentage, mean, standard deviation, X2-test, one-way ANOVA, Pearson correlation, and progressive regression through the SPSS/WIN 22.0 program. Emergency nursing performance by the assessor was negatively associated with the satisfaction of clinical practice (r=-.31, p=.005) and positively related to the subjective clinical performance (r=.23, p=.036). The affecting rate was just 12%, which was low for explaining the objective emergency nursing performance during the simulation. Further studies will be needed to explore other factors affecting the emergency nursing performance.

Market Discipline by Depositors : the Case of Mutual Savings Banks in Korea (상호저축은행과 예금자에 의한 시장규율)

  • Park, Jung-Hee
    • The Korean Journal of Financial Management
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    • v.26 no.1
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    • pp.95-125
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    • 2009
  • This paper examines the disciplinary effect of deposits using the semiannual accounting data of mutual savings banks(henceforth 'MSBs') in Korea for the period of 2003 through 2007. I find overall strong evidence in favor of the existence of market discipline in the industry. MSBs with higher BIS ratio and lower NPL ratio turn out to have higher increase rate of deposits than MSBs with lower such ratios. The coefficient of NPL ratio becomes greater with time, suggesting that the effect is cumulative. It turns out that depositors respond more sensitively to NPL ratio than BIS ratio in a period of MSB failure. On the other hand, MSBs turn out to act very positively responding to the depositors' discipline. They increase BIS ratio or decrease NPL ratio following the previous decrease in deposits. Government authorities need to make more efforts to develop a suitable incentive system (e.g. penalties on a false disclosure) to improve the efficiency of disclosure by MSBs. Moreover, they need to acknowledge the importance of NPL ratio as a market disciplinary tool which has been becoming more important, especially in times of MSB failure.

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The Composition of Candida guilliermondii Grown in Soybean Whey (Soybean Whey에 배양(培養)한 Candida guilliermondii의 균체조성(菌體組成))

  • Lee, Kang-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.11 no.1
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    • pp.21-24
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    • 1982
  • A strain of yeast (Candida guilliermondii KFCC 35120) was cultivated by using the soybean whey with supplement of blackstrap molasses (4%) and ammonium acetate (0.5%). By the cultivation continued for 48 hours, 8.1g of dry cell was produced. The cell was consisted of carbohydrate 39.3%, protein 40.5%, lipid 3.9%, nucleic acid 9% and ashes 6%. The protein was analyzed to contain 18% of glutamic acid and 10% of lysine. Other amino acids showed a content near that of FAO reference protein except Methionine. Total lipid content was varied by nutritional condition especially by the kind of carbon source, however it showed a content 1.7 to 2.5 times higher than that of Saccaromyccs cerevisiae. The lipid contain 48% of oleic acid, 17% linoleic acid and 4% linolenic acid. The content of linoleic and lonolenic acid was higher than that of S.cerevisiae by 9 and 24 times, respectively.

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Relationship Between Above-and Below-Ground Biomass for Norway Spruce (Picea abies) : Estimating Root System Biomass from Breast Height Diameter (독일가문비나무(Picea abies [L.] Karst)의 지상부(地上部)와 지하부(地下部) 생체량(生體量)에 관(關)한 연구(硏究) : 흉고직경(胸高直徑)에 의한 뿌리생체량(生體量) 추정(推定))

  • Lee, Do-Hyung
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.338-345
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    • 2001
  • This study was conducted to elucidate the relationship between the root structure and the crown structure of Norway spruce(Picea abies [L.] Karst), and thereafter to obtain the regression equation for the estimation of relative root and needle biomass using the tree height and diameter at breast height(DBH) without measurement of root and needle biomass. The study site was Barbis stands of Harz region located in central part of Germany. Five dominant and three co-dominant trees of 30 to 40 year-old Norway spruce were selected and tree height, diameter at breast height, clear bole length, weight of total needle and branch, cross section and sapwood area at breast height for biomass of above ground part and also the length of root, the number of root, the weight of root, the cross section area of root etc. by dividing the horizontal and vertical roots for below ground part of tree were measured. The significantly correlation was shown between the biomass of most of variables of above ground parts and those of below ground parts. For the diameter of breast height to the weight of total root, regression equation was Y = 3.56X - 45.94 and decision coefficient was 0.96 showing highly correlation. The weight of total branches and needles, and the tree height etc. of above ground parts showed highly positive relationship with below ground biomass. The results obtained from this study can be used to the estimating of biomass of below ground using variables of above ground such as DBH in the 30 to 40 year-old Norway spruce stands.

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Effects of Socioeconomic Factors and Forest Environments on Demand for Rural Residential Development (농촌 주거지 개발 수요에 대한 사회경제적 요인 및 산림환경의 영향 분석)

  • Lee, Yohan;Ji, Seongtae
    • Environmental and Resource Economics Review
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    • v.25 no.2
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    • pp.199-228
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    • 2016
  • This study investigates the effects of economic factors and forest environments on rural residential area development in seven north central states of the U.S. by focusing on the relative importance of not only economic factors but also forest environments by forest type as core drivers of residential development. An empirical model of locations and magnitudes of population changes since 1950 in the north central region is first constructed, and then a panel model with fixed effects for counties is used to explain population growth by age group over time at the county level. Then a set of three equations is estimated for three major age groups, and a cross-sectional model is estimated for the last time period that regresses county-level environmental amenity variables on fixed effects coefficients for counties. Finally, an equation explaining changes in rural housing density is estimated. The results imply that immigrant age is a key factor influencing the choice of the place of residence and that the effects of environmental amenity factors on population growth and subsequent housing development in a county vary according to the age group.

Effect of Heavy Metal Contents in Soils Near Old Zinc-Mining Sites on the Growth of and their Uptake by Soybean (아연광산 인근 토양중의 중금속 함량이 콩의 생육 및 중금속 흡수에 미치는 영향)

  • Lee, Jong-Pal;Park, No-Kwuan;Park, Seon-Do;Choi, Boo-Sull;Kim, Bok-Jin
    • Korean Journal of Environmental Agriculture
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    • v.15 no.3
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    • pp.275-281
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    • 1996
  • When soybean was cultivated in the polluted soil with heavy metals, the content of these heavy metals affected. The results were summarized as follows. 1. The growth of soybean was remarkably poor and the content of heavy metals in polluted soil were higher than in unpolluted soil. 2. In leaves of all surveyed crops, the content of Zn, Cu, Pb, Cd and As was higher in soybean, followed by corn and rice. 3. Except for Pb, the content of heavy metals in the leaves of soybean was higher than in the stem of soybean, and the components of heavy metals in each part of soybean were shown in order of Zn > As > Cd > Cu > Pb. 4. The relationship between the content of Zn, Cu, Pb, Cd, As and the growth of soybean was negatively correlated, respectively. 5. A higher correlation seemed to exist among the content of Zn, Cu, Pb, Cd, As in soil, of Zn, Cu and As in soybean leaves, and of Pb, Cd and As in stems of soybean. The results indicated that heavy metals were absorbed and accumulated by plants grown in the polluted area.

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Gasification Study of Datong Coal in a Bench Scale Unit of Entrained Flow Gasifier (Datong탄에 대한 Bench Scale Unit급 분류층 석탄가스화 연구)

  • Ryu, Si-Ok;Kim, Jae-Ho;Lee, Hyo-Jin;Lee, Jae-Goo;Park, Tae-Jun;An, Dal-Hong;Park, Ho-Young
    • Journal of Energy Engineering
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    • v.6 no.1
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    • pp.96-103
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    • 1997
  • Coal gasification experiments were performed to characterize the bench scaled unit of 0.5∼1.0 T/D entrained coal gasifier developed by KIER. Datong coal from China was selected for this study. The system was operated at the temperature range of 1300∼1550$^{\circ}C$, with 62.5% of coal water mixture on the basis of dry coal. Oxygen and slurry mixture were preheated prior to feeding into burner and the ratio of oxygen/coal was in the range of 0.8∼1.2. In the preparation of coal water mixture, 0.3 wt% of CWM1002 and 0.05 wt% of NaOH wire added to reduce viscosity as well as to enhance theological properties of slurry. The resultant gaseous products consist primarily of hydrogen, carbon monoxide, carbon dioxide, and minor amounts of methane. Formation of H$_2$and CO was increased, while CO$_2$was decreased as the reacting temperature being increased due to the char-CO$_2$reaction. Maximum production of H$_2$and CO occurred in the O$_2$/coal ratio of 0.9 at 1530$^{\circ}C$. Heating values of product gases were in the range of 1700∼2400 kcal/N㎥.

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Transient Intestinal Ileus in Neonate: A Study of Comparison with Hirschsprung's Disease (신생아기의 일시적 장폐쇄증: 허쉬스프룽병과의 비교 연구)

  • Choi, Kwang-Hae
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.2
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    • pp.194-198
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    • 2009
  • Purpose: Severe abdominal distension is not uncommon symptom in the neonate. Two major causes of this symptom are benign transient intestinal ileus (BTII) and Hirschsprung`s disease (HD). But it is difficult to differentiate BTII from HD based on the symptoms and simple abdominal x-ray findings. The aim of this retrospective study was to assess the clinical aspects and diagnostic tests differencing two diseases. Methods: From August 2004 to March 2009, nineteen patients with severe abdominal distension, who underwent barium enema, anorectal manometry, and rectal suction biopsy (triple tests) due to a suspicion of HD, were enrolled. A comparison of clinical data associated with BTII and HD based on the clinical features and results of triple tests. Results: The age of onset of symptom was between 2 and 6 weeks in BTII and within 3 weeks in HD. On the barium enema, transitional zone revealed in 6 (50%) patients in BTII and 4 (57.1%) in HD. On anorectal manometry, the anorectal inhibitory reflex was present in 11 (91.7%) patients in BTII and 1 (14.3%) in HD. On rectal suction biopsy, ganglion cell was present in 9 (75%) patients in BTII and 0 (0%) in HD. Abdominal distension was improved within 3 months of life in all cases of BTII. Conclusion: We think that anorectal manometry may be more simple and useful diagnostic method than barium enema and rectal suction biopsy for differential diagnosis of transient intestinal ileus and Hirschsprung's disease.

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