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        검색결과 146

        122.
        1996.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        연소화염법을 이용한 다이아몬드 박막합성은 기판의 표면상태에 크게 의존한다. 특히 탄소결합상이 기판에 조재하는 경우 다이아몬드 핵생성과 성장은 크게 영향을 받는다. 본 연구에서는 일정한 흡입가스비율(R=O2/C2H2)과 기판온도 조건의 연소화염법을 이용하여 몰리브덴 기판위에 다리아몬드박막을 합성하는 과정에서 박막의 핵생성에 미치는 기판 탄소화합물의 영향을 조사하였다. Mb 금속기판표면에 형성된 탄화물로는 Mo2C상과 soot를 택하여 박막합성 전에 Mo기판상에 형성시켰다. Mo 금속기판표면에 형성된 탄화물(Mo2C)상에는 다이아몬드 핵생성과 입자성장이 촉진되어 가장 조대한 양질의 다이아몬드 입자가 형성되었다. 이것은 탄화물상이 반응가스중의 탄소의 확산을 저지함과 동시에 핵생성의 필요한 잠복기간을 감소키켰기 때문이다. 그러나 soot를 구성하는 미세한 탄소결합상들이 다이아몬드 핵생성 장소로 작용하여 결과적으로 다이아몬드 수밀도가 가장 크게 관찰된 반면, 입자성장은 Mo2C기판에 비해 작았다.
        4,000원
        126.
        1994.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        연소화염법을 이용한 다이아몬드 박막합성시 기판표면온도 및 온도분포에 가장 크게 작용하는 공정변수는 탄화수소량을 결정하는 산소/아세틸렌 가스의 혼합비(R=O2C2H2)이다. 본 연구에서는 혼합가스비율 변화 (R=0.87-0.98)에 따른 기판표면온도 및 온도분포를 측정하고, 이들 변수에 따른 다이아몬드 박막의 생성 및 결정형상의 변화과정을 SEM관찰, Raman 분광분석 및 X-선 회절 분석을 통해 조사하였다. 혼합가스비율의 증가에 따라 다이아몬드의 생성입자 수밀도는 감소하였고, 이와 동시에 결정형상도 (111)면과 (100)면이 혼재된 cobo octahedron형에서 octahedron인 (111)면으로 변화되었다. 한편, 기판온도증가에 따라 생성입자의 수밀도가 증가하고 성장속도도 빨라져 조대한 결정을 얻었으며, 생성된 입자형성은 (111)면애 지배적이다가 (100)결정면이 점차 많아지는 양상을 나타내었다.
        4,000원
        129.
        1994.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The mechanism of activated sintering of tungsten powder was discussed in terms of diffusion and segregation of activator atoms at W grain boundaries. Shrinkage behaviours of W-0.2wt.% Ni, W-0.2wt.% Cu or pure W powder compacts during sintering at low temperatures of 900~ were investigated. It was found that the Cu additive inhibits sintering process causing lower densification than pure W compact while remarkable shrinkage occurred in the Ni added W powder. Such contrary effect was explained by comparing self diffusion processes along Ni or Cu segregated W boundaries in which Ni segregants enhance but Cu atoms retard the migration of W atoms at W boundaries.
        4,000원
        133.
        2018.09 KCI 등재 서비스 종료(열람 제한)
        This paper proposes functional test methods of first-aid gadgets which are special end-effectors, for relief robot. In recent years, researches have been actively conducted on robots that can perform rescue operations on behalf of rescue workers in dangerous areas such as disasters and wars. These special robots mainly perform the task of finding or transporting injured people. However, it is sometimes they necessary to provide first aid in the field. Among the various first-aid operations, gadgets are being developed for oxygen supply, injection, and hemostasis operations that can be used in a defense/civilian area by using robot technology. Previous studies have proposed first-aid gadgets that are suitable for onsite situations and enable robots to perform the given task quickly and accurately. In this paper, we design a test procedure suitable for the functions of first-aid gadgets, summarize the results, and introduce future research directions.
        134.
        2018.04 서비스 종료(열람 제한)
        In the case of the port mooring facility, jetties with piles are mainly applied in soft ground conditions. In the three-dimensional modeling for the structural analysis of jetties with piles, the boundary conditions between the pile and the ground are universally applied to the Approximate depth of pile supported method and Elastic subgrade reaction spring method. In this study, p-y curve data for the pile ground condition was generated using the LPILE program, and then the nonlinear spring considering the p-y curve as the pile and ground boundary condition was input and analyzed in the 3D modeling of jetties with piles using the MIDAS civil And the necessity of applying the Nonlinear subgrade reaction spring method by comparison with the result and the analysis result according to the existing analysis method is suggested.
        135.
        2017.04 서비스 종료(열람 제한)
        According to this research, it was confirmed that safety coefficient is useful tool to rationally quantify structural deterioration of pipe. In addition, it could perform simple and rapid evaluation escaping from confinement by time and budget, and it can be utilized as a tool to set up policy for future water supply.
        136.
        2015.09 서비스 종료(열람 제한)
        The present study aimed to identify the factors that can clinically predict responses to macrolides treatment in patients with Mycoplasma pneumoniae pneumonia. Of the patients admitted to the pediatrics department of Kwangju Christian Hospital during December 2012 to March 2015, 195 patients who had pneumonia according to findings of chest radiography, positive Mycoplasma IgM, and fever at the time of admission were selected as study subjects. Patients were divided into one group wherein the duration of fever after macrolides treatment was 3 days or less and another group wherein the duration of fever was 4 days or more (169 patients [86.7%] vs 26 patients [13.3%]). In the group with fever duration of 4 days or more, a greater number of patients had a history of atopic dermatitis (3.6% vs 15.4%, p=0.11), and the symptom duration before admission was longer (cough: 4.04 days vs 6.38 days, p<0.001; fever: 3.96 days vs 6.08 days, p<0.001). Moreover, according to laboratory test results in the group with fever duration of 4 days or more, LDH levels were high (648.16 IU/L vs 829.92 IU/L, p=0.001), and there was a significant correlation between LDH levels and the duration of fever after macrolides treatment.
        137.
        2014.09 서비스 종료(열람 제한)
        Retrospective analysis was conducted on the clinical data of 38 cases of bacterial meningitis that were proven by cerebrospinal fluid culture. Each case occurred by GBS (68.4%), Pneumococcus (15.8%), E. coli (5.3%), Streptococcus mitis (5.3%), Streptococcus bovis (2.6%), and Staphylococcus xylosus (2.6%). Compared to 28 cases with normal outcome, 10 cases who died or had adverse outcomes at hospital discharge were more likely to present with coma, seizure (before or within admission, focal, status epilepticus), require pressor or ventilator support, have initial peripheral blood leukocyte count less than 4,000/mm3 or neutrophil count less than 1,000/mm3, and have hydrocephalus or cerebral infarction by brain imaging.
        138.
        2014.06 KCI 등재 서비스 종료(열람 제한)
        We investigated the spatiotemporal variations of dissolved inorganic nutrients along a saline gradient to estimate nutrient fluxes in the Seomjin River estuary during dry (March 2005, March 2006, March 2007, and March 2008) and rainy seasons (August 2005, July 2006, July 2007, and July 2008). Dissolved inorganic nitrogen concentrations were similar in the endmembers of freshwater for the rainy and dry seasons. In contrast, the concentrations of dissolved inorganic phosphate and silicate in the rainy season were approximately 2-3 times higher than those in the dry season. River discharge was approximately 10 times higher in the rainy season (212 m3 sec-1) than in the dry season (21 m3 sec-1). The fluxes of dissolved inorganic nitrogen, phosphate, and silicate were 2.91, 0.004, and 2.51 tons day-1 in the dry season and 7.45, 0.421, and 30.5 tons day-1 in the rainy season, respectively. Although the range of nutrient concentrations were similar to previous results from investigations in the Seomjin River estuary, the nutrient fluxes were differed according to river discharge for different survey periods.
        139.
        2013.12 서비스 종료(열람 제한)
        Prevalence of Mycoplasma pneumoniae pneumonia in preschool children has shown a recent increase and macrolideresistant Mycoplasma pneumoniae pneumonia has been reported. We investigated the clinical features of Mycoplasma pneumoniae pneumonia among children of different ages and different years for the most recent seven years. Retrospective analysis was performed on the clinical data of 735 children who were hospitalized due to Mycoplasma pneumoniae pneumonia between January 2006 and December 2012. The children were divided into three groups according to age: the A group (<3 years), B group (≥3 years and <7 years), and C group (≥7 years). In addition, the children were divided into two groups according to the year in which the disease had developed: the early period (2006 and 2007 year), and the late period (from 2010 to 2012 year). The infant group (A group) presented mainly with a shorter duration of fever and more frequent wheezing. In the late period, the interval until improvement after a macrolide was prescribed increased. Clinical features of Mycoplasma pneumoniae pneumonia differed among children of different ages, particularly between infants and school-aged children.
        140.
        2013.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The antifungal activity against cheese fungi by lactic acid bacteria isolated from kimchi was investigated. Eight fungi were isolated from cheese in the cheese ripening room. Two of them were identified as Penicillium and Cladosporium via ITS-5.8S rDNA analysis. Twenty-two species of lactic acid bacteria with antifungal activity were isolated from kimchi. Two of them were identified as Lactobacillus and Pediococcus via 16S rRNA sequence analysis. Of the 22 lactic acid bacteria species, six were selected (L. sakei subsp. ALJ011, L. sakei subsp. ALI033, L. sakei subsp. ALGy039, P. pentosaceus ALJ015, P. pentosaceus ALJ024 and P. pentosaceus ALJ026) due to their higher activity against the eight fungi isolated from cheese in the cheese ripening room; and among the six species, the P. pentosaceus ALJ015 and P. pentosaceus ALJ024 isolates from the Jeonju area kimchi and the L. sakei subsp. ALI033 isolate from the Iimsil area kimchi had higher antifungal activity than the other lactic acid bacteria. The minimum inhibitory concentration (MIC) of L. sakei subsp. ALI033 against the eight fungi isolated from cheese in the cheese ripening room was 62.5 ㎍/mL.
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