• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.615-618
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• 2004

The piezoelectricity and polarization of multilayer ceramic actuators, being designed to stack ceramic layer and electrode layer alternately, were investigated under a consideration of geometry, the thickness ratio of the ceramic layer to electrode layer The actuators were fabricated by tape-casting of $0.42PbTiO_3-0.38PbZrO_3-0.2Pb(Mn_{1/3}Nb_{2/3})O_3$ followed by laminating, burn-out and co-firing process. The actuators of $5\times5mm^2$ in area were formed in a way that $60{\sim}200{\mu}m$ thick ceramics were stacked 10 times alternately with $5{\mu}m$ thick electrode. Increase in polarization and electric field-displacement with increasing thickness ratio of the ceramic/electrode layer and thickness/cross section ratio were attributed to the change of $non-180^{\circ}/180^{\circ}$ domain ratio which was affected by the interlayer internal stress and Poisson ratio of ceramic layer. The piezoelectricity and actuation behaviors were found to be dependent upon the volume ratio (or thickness ratio) of ceramic layer relative to ceramic layer. Concerning with the existence of internal stress, the field-induced polarization and deformation were described in the multilayer actuator.

• 복식문화연구
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• 제26권4호
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• pp.613-631
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• 2018

The purpose of this study is to collect and analyze costumes presented in international dance sports competitions, and summarize the features of Latin American dance costumes' design. As for research methods, standards of Latin American dance costume design were analyzed via a literature review on dance sports. The scope of the study extended for six years from 2010 to 2015 to include the, top three UK Latin American dance competitions. The results are as follows. First, the silhouette analysis determined that the X silhouette to the lead with, -145 costumes (78%), followed by the H silhouette at 25 (13%), and other at 16 (9%). Amongst those there were 174 one-piece dresses (94%). Furthermore, the analysis on colors of Latin American dance sports costumes revealed that, amongst the 186 costumes, 115 were without color (62%), Bl(black) is the most frequent with 37%, then Wh(white) with 21% and Gr(gray) with 4%. Costumes with colors, based on the six basic colors in the Munsell color system, are comprised most often of red with 12%, the followed by Y(yellow) at 10%, B(blue) at 8%, YR(yellow-red) at 4%, P(purple) at 2%, and G(green) at 2%. Thirdly, the cloth materials of Latin American dance costumes are recognized through image inspection. Among visually recognizable materials, beading materials are the most common with 104 costumes (60%). Shiny materials like mesh, chiffon, organza, lace and burn-out are in 36 costumes in total (19%). Other cloth materials included Luster materials and; non-sheen materials, which were in 46 costumes (25%).

• 기본간호학회지
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• 제20권3호
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• pp.278-288
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• 2013

Purpose: The purpose of this study was to investigate the influence of communication competence and burnout on nursing performance in intensive care units (ICU). Method: The participants were 209 nurses from four university hospitals. Measurements included a socio-demographic and job related survey, communication competence inventory, the Maslach burnout inventory and a nursing performance scale. Data were collected from February 6 to 24, 2012, with a self-report questionnaire. The statistical analyses were performed with SPSS 18.0 software. Results: The mean scores for communication competence, burnout and nursing performance were 50.49, 84.72, and 62.18, respectively. Communication competence (r=.44, p<.001) and burn out (r=-.32, p<.001) were significantly correlated with nursing performance. In the multiple linear regression, factors influencing nursing performance were communication competence, age and burnout. These variables explained about 46% of the total variance of nursing performance. Communication competence (${\beta}$=.34, p<.001) was the most influential factor. Conclusion: Nurses' poor communication skills and burnout can influence the occurrences of medical errors in ICU nursing performance. The results suggest that good communication and burnout resolution skills programs should be implemented to improve nursing performance efficiency.

• 대한치과기공학회지
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• 제34권4호
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• pp.353-359
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• 2012

Purpose: The aim of this study measured and compared the marginal and internal fit of metal cores with two base metal alloy (Ni-Cr alloy(non-beryllium), Co-Cr alloy). Methods: Maxillary right first molar abutment fabricated by titanium was prepared for this study. Impressions(10ea) were made from titanium model, and study models were poured with improved dental stone. Wax cores of twenty were prepared for burn-out and casting. Ten wax cores cast Ni-Cr alloy(non-Be), and finally ten cast Co-Cr alloy. Marginal and internal fit of cores was evaluated using silicone replica technique and digital microscope(x160). The data were statistically analyzed with the independent samples t-test (${\alpha}$ <.05). Results: Mean(standard deviation, SD) marginal and internal fit total size of Ni-Cr alloy(non-Be) group was $73.3(14.4){\mu}m$ and of Co-Cr alloy group $65.6(17.4){\mu}m$. The marginal and internal fit total size of Ni-Cr alloy group(non-Be) was statistically significantly greater than that of Co-Cr alloy group (P=.004). Conclusion: Co-Cr alloy cores in this study had a better marginal fit than Ni-Cr alloy(non-Be) cores.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1977-1980
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• 2014

Background: The popularity of the narghile waterpipe, also referred to as hookah, shisha or hubble-bubble has increased tremendously during the past few decades. The aim of this study was to expose perception of narghile among a representative sample of university students in Sakarya University campus. Materials and Methods: Written approval was taken from the local education authority. An anonymous questionnaire which was prepared by the investigators and contained 17 questions was administered. Nine of the questions were related to socio-demographic characteristics and eight were related to the students harm perceptions about waterpipe. A total of 1,320 questionnaries were received and after preliminary evaluation 1,255 (95.7%) were found to be suitable for evaluation. The data was evaluated in SPSS program by using percentages and averages. Results: The $mean{\pm}SD$ age of the students was $20.8{\pm}2.29$ years (min 18, max 32). There were 864 (68.8%) females and 391 (31.2%) males. A total of 6.3 % of the students (n=79) believed that waterpipe is not harmful because its smoke does not burn the lungs. Almost one-third (n=318) think that the carcinogenic chemicals are filtered while waterpipe smoke passes from the water; 12.1 % of the students (n=152) checked "true" for the statement of "waterpipe smoke contains no nicotine". It is seen that 14.0 % of the students (n=176) think waterpipe with fruit/aroma is healthier than plain waterpipe. Conclusions: As a result of this study, it is found out that a substantial number of university students have false beliefs on harmful effects of waterpipe smoking.

• 종양간호연구
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• 제3권1호
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• pp.75-84
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• 2003

Purpose: this study was to identify influencing factors of burnout on oncology nurses. Method: the data was collected using a questionnaire from October 18, 2002 to November 20, 2002 in five general hospitals at Seoul. Participants of this study were the nurses who worked in the wards occupied by more than 50 percent of cancer patients. The collected data were analyzed by using the SPSS10.0 program. Result: 1. The burnout of the subjects show a mean score of 2.72 using the 5 point Likert scale. There were statistically significant difference in burnout between the general characteristics; age, marital status, educational background, job experience, position, nursing service period, and attitudes on nursing job. 2 The self-esteem of the subjects show a mean score of 3.72 using the 5 point Likert scale. The spiritual well-being of the subjects show a mean score of 3.83 using the 6 point Likert scale. The social support of the subjects show a mean score of 3.74 using the 5 point Likert scale. The job stress of the subjects show a mean score of 2.16 using the 4 point Likert scale. 3. The result of correlation between burnout and other variable was that relationship between the burnout and job stress(r=-.206, p<.05), self-esteem(r=-.417, p<.01), spiritual well-being(r=-.403, p<.01), social support(r=-.386, p<.01) were significant variables. 4. The result of the Stepwise Multiple Regression was that self-esteem (17.4%), spiritual well-being(7.9%), social support(3.4%) and job stress(2.3%) explained 31% of burn out.

• 폴리머
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• 제26권2호
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• pp.200-208
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• 2002

난연성분인 트리클로로벤조산(TBA)의 함량을 10, 20, 30 wt%로 변화시키면서 아디프산, 1,4-부탄디올 및 트리메틸올프로판과 축중합을 하여 트리클로로 락톤 변성폴리에스테르(TAPTs)를 합성한 후에, TAPT류와 이소시아네이트인 Desmodur IL을 블렌드하여 2성분계 폴리우레탄 난연 도료를 제조하였다. 제조된 난연도료의 도막물성을 측정한 결과, 결코 비난연도료보다 물성이 떨어지지 않음을 알았다. 또한 난연도료의 3종류 난연성 시험결과, 수직법에서 TBA 함량 20 wt% 이상에서 불꽃에 타지 않았고, LOI 연소성 시험에서 TBA 함량 20, 30 wt%시 25%와 27%의 LOI값을 나타내었으며, $45^{\circ}$ Meckel burner법에서는 탄화길이가 3.6-5.2 cm로서 난연 1급에 해당되었으므로 이를 미루어 난연효과가 좋은 난연도료임을 알 수 있었다.

• 한국콘텐츠학회논문지
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• 제15권6호
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• pp.432-444
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• 2015

본 연구는 Schaufeli & Bakker(2004)의 직무요구-자원 이론을 적용하여 병원이라는 특수한 조직 환경안에서 나타나는 직무요구-자원 변수들이 직무소진과 직무열의에 있어 어떠한 영향을 미치는지 살펴보고 그 과정에서 감정노동전략의 차별적 매개역할을 검증하였다. 연구결과를 살펴보면 직무요구-자원은 직무소진과 직무열의에 있어서 정적인 관계를 나타냈고 직무요구는 표면행동을, 직무자원은 내면행동을 유발하였다. 그러나 내면행동은 직무열의에 정적인 관계를 보였고 표면행동은 기존의 연구결과와 달리 직무소진과 부적인 관계를 나타냈으나 유의하지 않았다. Boostrap을 통해 매개모형을 검증한 결과 두 간접효과가 유의하지 않아 직무요구-자원수준이 직무태도인 직무소진과 직무열의에 미치는 영향에 있어서 감정노동 전략수행의 매개역할은 검증되지 않았다.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.179-189
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• 2008

The performance of Lean NOx Trap (LNT) based on the catalysts of Pt/K/Ba/$\gamma-Al_2O_3$ with proprietary washcoat formulation is studied using a bench flow reactor system. To investigate the effect of temperature and gas hourly space velocity (GHSV) on the nitrogen oxides (NOx) trapping capacity as well as NOx breakthrough time and final ratio of $NO_2$ to NO of LNT, series of adsorption isotherms are carried out with simulated exhaust gases of the lean burn engines. Since typical operation of LNT requires periodic regeneration with a short rich excursion, where the stored or trapped NOx is released and subsequently reduced to $N_2$, the effect of the duration of lean and rich phase and type of reductants on the NOx conversion is investigated. NOx storage capacity and breakthrough time obtained from adsorption isotherms shows a volcano-type dependence on the temperature with a maximum NOx storage capacity occurring $350^{\circ}C$ and with a maximum breakthrough time occurring $400^{\circ}C$ at all GHSVs investigated in this study. Also, maximum ratio of $NO_2$ to NO is obtained at $400^{\circ}C$ with a GHSV of $75,000\;hr^{-1}$ Lean/rich cycle of 100 s lean and 5 s rich used with a concentration of 1.33% of $H_2$ and 4% of CO in the rich phase is found to be optimum at operating temperature of $350^{\circ}C$ and a GHSV of $50,000\;hr^{-1}$.

• Nuclear Engineering and Technology
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• 제42권5호
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• pp.576-581
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• 2010

KAERI (Korea Atomic Energy Research Institute) fabricated MOX (Mixed Oxide) fuel pellets as a cooperation project with PSI (Paul Scherrer Institut) for an irradiation test in the Halden reactor. The MOX pellets were fitted into fuel rods that included instrumentation for measurement in IFE (Institutt for Energiteknikk). The fuel rods were assembled into the test rig and irradiated in the Halden reactor up to 50 MWd/kgHM. The irradiated fuel rods were transported to the IFE, where ceramography was carried out. The fuel rods were cut transversely at the relatively higher burn-up locations and then the radial cross sections were observed. Micrographs were analyzed using an image analysis program and grain sizes along the radial direction were measured by the linear intercept method. Radial cracks in the irradiated MOX were observed that were generally circumferentially closed at the pellet periphery and open in the hot central region. A circumferential crack was formed along the boundary between the dark central and the outer regions. The inner surface of the cladding was covered with an oxide layer. Pu-rich spots were observed in the outer region of the fuel pellets. The spots were surrounded by many small pores and contained some big pores inside. Metallic fission product precipitates were observed mainly in the central region and in the inside of the Pu spots. The average areal fractions of the metallic precipitates at the radial cross section were 0.41% for rod 6 and 0.32% for rod 3. In the periphery, pore density smaller than 2 ${\mu}m$ was higher than that of the other regions. The grain growth occurred from 10 ${\mu}m$ to 12 ${\mu}m$ in the central region of rod 6 during irradiation.