• Restorative Dentistry and Endodontics
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• 제13권2호
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• pp.207-220
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• 1988

The purpose of this study was to measure roughness on the polished surfaces of composite resin, and was to observe the polished surfaces under Scanning Electron Microscope. The surface roughness tester (Surfcom 700A Semitsu Profilometer Tokyo. Japan) was used to measure roughness of polished surfaces. In this study, 4 brands of composite resin were examined, Pyrofil bond anterior Bell-Feel anterior Clearfil F II and Microrest A.P. White point, Silicone point, Super snap, and Sof-Lex medium disc as cutting instrument, and celluloid matrix were used. The results obtained were as follows. 1) The celluloid matrix produced the smoothest surfaces. 2) Microrest composite resin had smoother surface than any other composite resins after polishing. 3) The values of surface roughness made by White point, Silicon point and Super snap were similar. 4) The surfaces made by Sof-Lex medium disc was smoother than the surfaces made by any other polishing instruments.

• 응용통계연구
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• 제27권3호
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• pp.387-396
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• 2014

GDP갭(gap)이란 잠재GDP와 실제GDP의 격차로서 산출갭(Output gap)이라고도 한다. 잠재GDP는 노동, 자본 등 생산요소를 완전히 활용하여 달성할 수 있는 최대GDP라고 정의할 수 있다. GDP갭은 수요-공급간 불균형을 의미한다고 할 수 있으며 이러한 특성 때문에 물가 및 고용안정을 추구하는 중앙은행들은 정책수행과정에서 GDP갭을 중요한 정보변수로 활용하고 있다. 본 연구에서는 우리나라의 GDP갭을 그간 선행연구에서 사용하였던 필터링 방법에 의해 분해함으로써 GDP갭 변동을 야기하는 주요 요인이 무엇인지 살펴보았다. Fox 등 (2003)와 Fox와 Zurlinden (2006)에서 사용되었던 Super Smoother 알고리즘을 이용하여 우리나라의 명목GDP갭을 분해해 본 결과 이론적인 설명에 부합하는 것으로 나타났다. 명목GDP갭률 변동의 상당부분은 잔차인 총요소생산성으로 설명됨을 알 수 있었는데, 이는 최근들어 급격한 기술변화 및 환경변화 등 생산성 변화가 GDP변동에 큰 영향을 주고 있음을 의미한다. 다른 나라의 경우와 마찬가지로 국내물가의 영향력도 높은 것으로 나타났지만 대외 의존도가 높은 우리 경제의 특성상 교역조건의 변동 역시 상대적으로 명목GDP 움직임에 큰 영향을 주고 있는 것으로 분석되었다.

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.67-80
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• 1990

This study was performed for elucidating the effects on surface polishing of composite resins. In this study, Silux(microfilled), Graft(hybrid), Bisfil- I (hybrid posterior) and Hi-pol(conventional) were used. Sixty specimens were made with 4 brands of composite resins and Optilux system in $2.0{\times}1.3{\times}1.0cm$ resin block which has a cavity with 0.5cm diameter and 0.5cm depth. Polishing was done with #600 sand paper and Soflex, Super-snap, Micron finishing system, or Composite polishing kit. Final polished surfaces were measured by roughness tester(Kasaka Lab. Ltd., Japan) and image analyser(Omnimet Image Analyser, Buehler, USA). The results were as follows, 1. The celluloid strip produced the smoothest surfaces. 2. Light curing microfilled composite resin, Silux, had smoother surface than any others. 3. The surfaces polished by Soflex were smoothest. 4. Aluminum oxide disk, Soflex and Super-Snap, made smoother surface than diamond bur, M.F.S., or silicon point, Composite polishing kit. 5. The roughness values of surface polished by M.F.S. composed of diamond burs, were less than those of Composite polishing kit made from silicone points.

• Restorative Dentistry and Endodontics
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• 제16권2호
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• pp.197-212
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• 1991

The purpose of this study was to roughness on the polished surface of visible light composite resins and was to observe the polished surfaces under Scanning Electrom Microscope(ISI DS 130 AKASHI Co. JAPAN). The surface roughness tester(Surfcom 700A Seimtsu profilometer Tokyo, Japan) was used to measure roughness of polished surfaces. In this study, 5 brands of visible of composite resins were examined, Pyrofile light bond Anterior Lite fil anterior Photo clearfil anterior & posterior Palfique light Anterior and posterior Silux Anterior. White point, Silicure point, Super snap Sof-Lex medium disk as cutting instrument, and celluloid matrix were used. The results obtained were as follows. 1. The Celluloid matrix produced the smoothest surfaces. 2. The surfaces made by Soflex medium disk was smoother than the surfaces made by any other polishing instruments. 3. The values of surface roughness made by White point, Silicon point and Super snap were similer. 4. Palfique light (AP) visible light composite resin showed the smoothest surface after polishing with Silicone point, Super snap disk and Soflex mediuem disk in all tested materials.

• 천문학회보
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• 제44권2호
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• pp.44.1-44.1
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• 2019

We generate new intermediate images between observed consecutive solar images using NVIDIA's SuperSloMo that is a novel video interpolation method. This technique creates intermediate frames between two successive frames to form a coherent video sequence for both spatially and temporally. By using SuperSloMo, we create 600 images (12-second interval) using the observed 121 SDO/AIA 304 Å images (1-minute interval) of a filament eruption event on December 3, 2012. We compare the generated images with the original 12-second images. For the generated 480 images the correlation coefficient (CC), the relative error (R1), and the normalized mean square error (R2) are 0.99, 0.40, and 0.86, respectively. We construct a video made of the generated images and find a smoother erupting movement. In addition, we generate nonexistent 2.4-second interval images using the original 12-second interval images, showing slow motions in the eruption. We will discuss possible applications of this method.

• 해양환경안전학회지
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• 제25권3호
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• pp.306-312
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• 2019

This paper investigates to design a controller for maritime autonomous surface ship (MASS) by means of adaptive super-twisting algorithm (ASTA). A input-out feedback linearization method is considered for multi-input multi-output (MIMO) system. Sliding Mode Controller (SMC) is suitable for MASS subject to ocean environments due to its robustness against parameter uncertainties and disturbances. However, conventional SMC has inherent disadvantages so-called, chattering phenomenon, which resulted from the high frequency of switching terms. Chattering may cause harmful failure of actuators such as propeller and rudder of ships. The main contribution of this work is to address an appropriate controller for MASS, simultaneously controls surge and yaw motion in severe step inputs. Proposed control mechanism well provides convergence bewildered by external disturbances in the middle of steady-state responses as well as chattering attenuation. Also, the adaptive algorithm is contributed to reducing non-overestimated value of control gains. Control inputs of surge and yaw motion are displayed by smoother curves without excessive control activities of actuators. Finally, no overshoot can be seen in transient responses.

• 원예과학기술지
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• 제30권5호
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• pp.579-585
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• 2012

This study was carried out to investigate the effect of potassium silicate on the growth and leaf epidermal characteristics of horticultural crops viz., begonia (Begonia semperflorens Link et Otto) 'Super Olympia Red' and 'Super Olympia Rose' and pansy (Viola ${\times}$ wittrockiana Hort.) 'Matrix White Blotch' and 'Matrix Yellow Blotch' in vitro. Seeds after germination were grown on a quarter strength MS medium supplemented with potassium silicate ($K_2SiO_3$) at 0, 100, 200, or $300mg{\cdot}L^{-1}$ and were maintained under a photoperiod of 16 hours at $25^{\circ}C$. Growth parameters such as plant height, root length, chlorophyll content, fresh, and dry weights have been recorded after a growth period of 58 days for begonia and 94 days for pansy. In begonia, fresh weight was significantly greatest in the $200mg{\cdot}L^{-1}$ $K_2SiO_3$ treatment in both 'Super Olympia Red' and 'Super Olympia Rose'. In both pansy cultivars, fresh weight was the greatest in the $200mg{\cdot}L^{-1}$ $K_2SiO_3$ treatment than other treatments. Chlorophyll content was significantly greater in the $100mg{\cdot}L^{-1}$ $K_2SiO_3$ treatment for both the cultivars of begonia. Leaf area significantly increased with the higher concentrations of $K_2SiO_3$ treatment in both cultivars of pansy. Stomatal structures on the leaf epidermis were observed with scanning electron microscopy (SEM). In begonia 'Super Olympia Rose', the structure of stomata were more compact in size in the $300mg{\cdot}L^{-1}$ $K_2SiO_3$ treatment than in the control. Similarly, in pansy 'Matrix White Blotch' the surface of stomata appeared to be smoother in the $300mg{\cdot}L^{-1}$ $K_2SiO_3$ treatment than those wrinkled appearance in the control. The surface of the leaf epidermis appeared to be compact due to Si deposition, and thus results indicated that Si positively affected the growth and biomass production of these species. Our data show that the effect of Si on growth parameters is strongly dependent on cultivar of the plant species tested.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.397-404
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• 1999

It is essential to measure load transfer mechanism of pile to check the appropriateness of assumptions made for design purpose and to continuously monitor the behavior of pile foundation. Through many attempts to monitor the behavior of super-structure in civil engineering area using several optical fiber sensors have been made, application of optical fiber sensor technology on pile foundation has not been tried up to now. Load transfer of model piles during compression loading was measured by optical fiber sensors and compared with the measurement by strain gauges. Fiber Bragg Grating(FBG) sensor system was used since it has many advantages, such as easy multiplexing, high sensitivity, and simple fabrication. Besides the model pile tests, uniaxial tension test of steel bar and compression tests of mortar specimen were carried out to evaluate the performance of FBG sensors in embedded environments. The shift of refilming wavelength due to the strain in FBG sensor is converted to the strain at sensor location and the dependence between them is 1.28 pm/${\mu}$ strain. FBG sensors embedded in model pile showed a better survivability than strain gauges. Measured results of load transfer by both FBG sensors and strain gauges were similar, but FBG sensors showed a smoother trend than those by strain gauge. Based on the results of model pile test, it was concluded that the use of FBG sensor for strain measurement in pile has a great potential for the analysis of pile load transfer.

• 한국기계가공학회지
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• 제2권1호
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• pp.15-21
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• 2003

The ultrasonic polishing machine was developed to get super finishing that consist of machine part that can rotate and travel the main shaft with power 1.5kW, ultrasonic generator with frequency 20kHz. By using this machine we were investigated the characteristics of ultrasonic polishing for three different ceramics, and so could be obtained following results. First, we could be obtained the excellent surface for hard-ta-difficult cutting materials. Second, the effect of surface roughness for the feed rate could be shown that the more the feed rate Increases, the more the value of surface roughness increases. Third, owing to the characteristics being progressed brittle fracture in $Al_2O_3$ polishing with this machine, the value of surface roughness is larger than other ceramics. Forth, because the ultrasonic polishing can be smoother than the existing grinding in discharging the chips, it could be possible to improve the surface roughness about up to 15%.

• 산업진흥연구
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• 제8권4호
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• pp.123-129
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• 2023

본 연구는 초고령사회에서 겪을 수 있는 노인에 대한 경제적 배제를 논의하고 이를 극복하기 위해 사회관계망 확충을 통해 노인의 인간관계만족도를 향상시키는 방안을 제안하고자 하였다. 본 연구 결과, 첫째, 경제적 배제를 극복하고 인간만족도를 향상시키는 방법은 그 대상에 있어서 여성에 대한 관심이 높아야 된다는 것을 암시하고 있으며, 고연령층, 저학력층, 저소득층에 대한 경제적 배제의 극복이 시급한 것으로 나타났다. 둘째, 사회관계망이 인간관계만족도에 미치는 영향을 조사한 결과, 여성일수록, 연령이 높을수록, 주소비처가 쇼핑일수록, 자녀와의 소통이 원활할수록 인간관계 만족도가 높아지는 것으로 나타났다. 따라서 사회관계에 대한 개선책이 요구된다고 볼 수 있다. 셋째, 경제적 배제가 인간관계 만족도에 미치는 영향을 조사한 결과, 여가활동이 친지 및 친척 방문일수록, 사회관계망 이용처가 유료시설일수록 인간관계 만족도가 낮아지는 것으로 나타났다. 따라서 여가활동과 사회관계망에 대한 개선책이 요구된다고 볼 수 있다. 넷째, 사회관계망의 매개효과를 조사한 결과, 소득영역에서의 배제, 노동시장의 배제, 주거복지의 배제를 항목으로 하는 독립변수인 경제적 배제가 종속변수인 인간관계만족도에 영향을 미치는 인과관계에서 사회관계망은 완전 매개효과가 있는 것으로 나타났다. 결론적으로 경제적 배제와 사회관계망은 인간관계만족에 영향을 끼치며, 경제적 배제가 극복되어 사회관계망이 개선될 때 비로소 인간관계만족도는 향상되는 것으로 나타났다.