• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.411-411
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• 2012

Over the recent years, surface enhanced Raman spectroscopy (SERS) has dramatically grown as a label-free detecting technique with the high level of selectivity and sensitivity. Conventional SERS-active nanostructured layers have been deposited or patterned on rigid substrates such as silicon wafers and glass slides. Such devices fabricated on a flexible platform may offer additional functionalities and potential applications. For example, flexible SERS-active substrates can be integrated into microfluidic diagnostic devices with round-shaped micro-channel, which has large surface area compared to the area of flat SERS-active substrates so that we may anticipate high sensitivity in a conformable device form. We demonstrate fabrication of flexible SERS-active nanostructured substrates based on soft-lithography for simple, low-cost processing. The SERS-active nanostructured substrates are fabricated using conventional Si fabrication process and inkjet printing methods. A Si mold is patterned by photolithography with an average height of 700 nm and an average pitch of 200 nm. Polydimethylsiloxane (PDMS), a mixture of Sylgard 184 elastomer and curing agnet (wt/wt = 10:1), is poured onto the mold that is coated with trichlorosilane for separating the PDMS easily from the mold. Then, the nano-pattern is transferred to the thin PDMS substrates. The soft lithographic methods enable the SERS-active nanostructured substrates to be repeatedly replicated. Silver layer is physically deposited on the PDMS. Then, gold nanoparticle (AuNP) inks are applied on the nanostructured PDMS using inkjet printer (Dimatix DMP 2831) to deposit AuNPs on the substrates. The characteristics of SERS-active substrates are measured; topology is provided by atomic force microscope (AFM, Park Systems XE-100) and Raman spectra are collected by Raman spectroscopy (Horiba LabRAM ARAMIS Spectrometer). We anticipate that the results may open up various possibilities of applying flexible platform to highly sensitive Raman detection.

• 마이크로전자및패키징학회지
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• 제23권2호
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• pp.91-96
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• 2016

본에서는 저반사 나노구조 필름의 열 나노임프린트 공정 최적화를 위해 나노구조의 성형성과 광학적 특성에 대한 이형 온도의 영향을 평가하였다. 이형 온도에 따른 광학적 특성을 평가한 결과 $70^{\circ}C$까지는 이형 온도가 증가함에 따라 투과율과 반사율 특성이 향상되는 거동을 보였으나 그 이후에는 오히려 투과율이 감소하고 반사율이 증가하는 경향을 보였다. 이와 같은 이형온도에 따른 거동은 성형성에도 유사하게 관찰되었으며 자유체적 형성과 고분자 유동에 의한 것으로 보인다. 따라서, 이형 온도에 따라 고분자의 유동과 자유체적의 형성에 의한 패턴의 성형성이 결정되며, 이로 인해 광학적 특성에 영향을 줄 수 있음을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.393-393
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• 2012

Optically active nanostructures such as subwavelength moth-eye antireflective structures or surface enhanced Raman spectroscopy (SERS) active structures have been demonstrated to provide the effective suppression of unwanted reflections as in subwavelength structure (SWS) or effective enhancement of selective signals as in SERS. While various nanopatterning techniques such as photolithography, electron-beam lithography, wafer level nanoimprinting lithography, and interference lithography can be employed to fabricate these nanostructures, roll-to-roll (R2R) nanoimprinting is gaining interests due to its low cost, continuous, and scalable process. R2R nanoimprinting requires a master to produce a stamp that can be wrapped around a quartz roller for repeated nanoimprinting process. Among many possibilities, two different types of mask can be employed to fabricate optically active nanostructures. One is self-assembled Au nanoparticles on Si substrate by depositing Au film with sputtering followed by annealing process. The other is monolayer silica particles dissolved in ethanol spread on the wafer by spin-coating method. The process is optimized by considering the density of Au and silica nano particles, depth and shape of the patterns. The depth of the pattern can be controlled with dry etch process using reactive ion etching (RIE) with the mixture of SF6 and CHF3. The resultant nanostructures are characterized for their reflectance using UV-Vis-NIR spectrophotometer (Agilent technology, Cary 5000) and for surface morphology using scanning electron microscope (SEM, JEOL JSM-7100F). Once optimized, these optically active nanostructures can be used to replicate with roll-to-roll process or soft lithography for various applications including displays, solar cells, and biosensors.

• 대한간호학회지
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• 제50권3호
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• pp.313-332
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• 2020

Purpose: This year 2020 marks the 50th anniversary of the founding of the Korean Society of Nursing Science (KSNS). This study was aimed to explore development of caring and describe the 50 years of history of KSNS within the sociocultural context of Korea regarding academic footsteps, meanings, and implications for the future. Methods: This study used a historical research methodology using a literature review and bibliometric analysis. Relevant literature was reviewed and the published abstracts in the Journal of Korean Academy of Nursing (JKAN) were analyzed using VOSviewer. Results: Birth control and family planning in the 1970s was the main research topic. In the 1980s, the development of nursing concepts, theories, and philosophies was the mission of KSNS to extend the disciplinary boundary. In the 1990s, the progress of KSNS to become one of the woman-dominant healthcare professionals was the mission in the given period. Expanding the frontiers of KSNS to the extent of global standards was the undertaking of the nursing scholars in the 2000s. Lastly, in the 2010s, the quality and quantity improvement of KSNS and JKAN is expected to make our future even prosperous. The map visualization of the 50 years of research accumulation showed the comparable opposition of quantitative vs. qualitative research methodologies, equation modeling, and instrument development. Conclusion: These clusters of research demonstrates the efforts to make nursing evidence by Korean nursing scholars for the last five decades. The growth in the slope of KSNS and outcomes of JKAN are to carry on to an unimaginable extent in the future.

• Journal of Acupuncture Research
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• 제34권3호
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• pp.1-11
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• 2017

Objectives : The purpose of this study was to examine the effects of Acori Graminie Rhizoma Pharmacopuncture (PA-AG) at GV20 on cerebral ischemia-induced dementia in Mice. Methods : Mice were divided into the five following groups: normal, control, acupuncture, PA-AG (17 mg/kg), and PA-AG (34 mg/kg). All groups, except the normal group, had cerebral ischemia induced by occlusion of middle cerebral artery. The control group was not treated. The acupuncture, PA-AG (17 mg/kg), and PA-GA (34 mg/kg) groups were treated every other day with a total of 6 treatments. The effect of treatment was observed by Bax, Bcl-2, Bax/Bcl-2 ratio, cytochrome c, cresyl violet, and choline acetyltransferase staining. Results : In the PA-AG (34 mg/kg) group, the intensity of Bax was decreased and the intensity of Bcl-2 was increased. The Bax/Bcl-2 ratio also decreased in the PA-AG (34 mg/kg) group. The intensity of cytochrome c protein stain was decreased in the PA-AG (17 mg/kg) group. The density of neurons stained by cresyl violet and choline acetyltransferase (ChAT) was increased in the AT, PA-AG (17 mg/kg), and PA-AG (34 mg/kg) groups when compared with that of the control group. Conclusion : PA-AG at GV20 was effective on cerebral ischemia-induced dementia in mice.

• 한국대기환경학회지
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• 제32권6호
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• pp.613-623
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• 2016

In this study, pilot experiments were conducted by setting operation conditions to analyze characteristics of emission for air pollutant from small two-stroke engines. Emission factors of the measured concentration of pollutant were compared with EEA. Emission factor of CO analyzed by experiments - concentration, flow rate, fuel consumption, etc.- was estimated at 816,011 g-CO/ton-fuel in average. It was confirmed that more than 80% of the fuel consumption is discharged to the Carbon Monoxide, and that as the engine load becomes higher, emission factor of CO increases in the form of log function. The average emission factor of $NO_x$ and $PM_{10}$ was $3,801g-NO_x/ton-fuel$ and $3,730g-PM_{10}/ton-fue$l each. The deviation was not large by comparing the fuel-based emission factor of EEA and the result of this study. Since considerable pollutants are expected to be discharged from the small two-stroke engines, continuous research and support of the policy is required.

• 한국전자통신학회논문지
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• 제10권1호
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• pp.27-32
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• 2015

본 논문에서는 GNSS(Global-Navigation Satellite Service)에서 사용되는 단말기의 PCB(Printed Circuit Board) 전원안정화를 위해서 PCB 내층에 삽입될 EBG(Electromagnetic Band Gap) 구조체를 제안한다. 버섯모양의 제안된 EBG 구조체를 통한 PCB에서의 관심 금지대역폭/저지대역폭 주파수는 GNSS와 이동통신 관련 주파수를 포함하는 1.55GHz에서 1.81GHz이었으며, 시뮬레이션 결과, 이 구간에서 삽입손실(S21)이 약 -40dB 이하로 형성됨을 볼 수 있었다. 본 연구결과는 향후, PCB 회로 설계의 PDN(Power Delivery Network)구조의 안정화 향상 및 EMI(Electro Magnetic Interference) 대책에 효과적 대응이 유용할 것으로 기대된다.

• 대한치과보철학회지
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• 제43권3호
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• pp.379-392
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• 2005

Statement of problem. One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection, and in molars. Purpose. The purposes of this study were: (1) to compare the initial abutment screw detorque values of the six different implant-abutment interface designs, (2) to compare the detorque values of the six different implant-abutment interface designs after cyclic loading, (3) to compare the detorque values of regular and wide diameter implants and (4) to compare the initial detorque values with the detorque values after cyclic loading. Material and methods. Six different implant-abutment connection systems were used. The cement retained abutment and titanium screw of each system were assembled and tightened to 32Ncm with digital torque gauge. After 10 minutes, initial detorque values were measured. The custom titanium crown were cemented temporarily and a cyclic sine curve load(20 to 320N, 14Hz) was applied. The detorque values were measured after cyclic loading of one million times by loading machine. One-way ANOVA test, scheffe’s test and Mann-Whitney U test were used. Results. The results were as follows : 1. The initial detorque values of six different implant-abutment connections were not significantly different(p>0.05). 2. The detorque values after one million dynamic cyclic loading were significantly different (p<0.05). 3. The SS-II regular and wide implant both recorded the higher detorque values than other groups after cyclic loading(p<0.05). 4. Of the wide implants, the initial detorque values of Avana Self Tapping Implant, MIS and Tapered Screw Vent, and the detorque values of MIS implant after cyclic loading were higher than their regular counterparts(p<0.05). 5. After cyclic loading, SS-II regular and wide implants showed higher detorque values than before(p<0.05).

• 대한한의학회지
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• 제30권2호
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• pp.145-151
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• 2009

Objectives: The purpose of this study was to investigate distribution of pattern identification by age in stroke patients. Methods: From 1 April, 2007 to 29 September, 2008, 903 patients within a month after onset of stroke were included. Stroke patients were interviewed by oriental medicine doctors who used standard operation procedures for this study. A questionnaire was completed by a question-and-answer form between patients and doctors after explanation of details to patients and patients' agreement given. Results: Distributions of pattern identification in stroke patients differed by age groups. Dampness-Phlegm pattern was more common in the younger group aged under 80 years, while Yin-Deficiency pattern was more common in the older group aged over 80 years. Conclusions: In this study, we found a character of distribution of pattern identification by age in stroke patients within one month after stroke onset. We have concluded that these differences should be considered in the management and treatment of stroke patients.

• 한국초등과학교육학회지:초등과학교육
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• 제26권1호
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• pp.117-130
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• 2007

This study investigated the university proffssors', pre-service teachers' and in-service teachers' perceptions of the specialized science education courses in the 11 national universities of education in Korea, analyzed their perception differences, and made suggestions the future directions for the specialized courses. For this study, 46 university professors, 402 in-service teachers, and 336 pre-service teachers were participated nationwide. The results show that there were significant differences in their perceptions between the three groups. For university professors, for example, the acquisition of science content knowledge appeared to be the most important objective of the courses, whereas the other groups preferred the acquisition of more practical knowledge and skills that they could easily use and apply in their classroom teaching later. The university professors tended to think that the science specialized courses would be very useful to the teachers' teaching and contribute to developing their professionality. On the contrary, the in-service and pre-service teachers tended to think that the courses would be not so useful because science theories construct the courses rather than practical knowledge. The implications of these findings are discussed in relation to the future science teacher education.