• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.10
• /
• pp.5129-5152
• /
• 2016

Multi-view super-resolution (MVSR) aims to estimate a high-resolution (HR) image from a set of low-resolution (LR) images that are captured from different viewpoints (typically by different cameras). MVSR is usually applied in camera array imaging. Given that MVSR is an ill-posed problem and is typically computationally costly, we super-resolve multi-view LR images of the original scene via image fusion (IF) and blind deblurring (BD). First, we reformulate the MVSR problem into two easier problems: an IF problem and a BD problem. We further solve the IF problem on the premise of calculating the depth map of the desired image ahead, and then solve the BD problem, in which the optimization problems with respect to the desired image and with respect to the unknown blur are efficiently addressed by the alternating direction method of multipliers (ADMM). Our approach bridges the gap between MVSR and BD, taking advantages of existing BD methods to address MVSR. Thus, this approach is appropriate for camera array imaging because the blur kernel is typically unknown in practice. Corresponding experimental results using real and synthetic images demonstrate the effectiveness of the proposed method.

• Horticultural Science & Technology
• /
• v.34 no.3
• /
• pp.372-382
• /
• 2016

In this study, we investigated the effect of seed collection stage and alternating temperature on the germination of Deutzia paniculata (Hydrangeaceae). The seeds were collected from naturally growing D. paniculata populations in Mt. Palgong, Gyeonsangbuk-do, Korea every two weeks over a three month period from August through October, 2014, totaling five collections. We examined seed characteristics such as seed size (length and width) and weight, and germination percentages for each collection stage under four different germination temperature regimes. We also examined germination after 30 and 60 days of cold moist stratification. Each collection phase had a different germination percentage and the lowest germination percentage was observed in the seeds from phase I (average GP of 15.7%). The germination percentage was similar at the later collection phases and in the higher temperatures suggesting that later collection times and higher temperatures are optimal for D. paniculata germination. We found that the optimum collection stage with high viability and germination percentage of for D. paniculata was during the middle of the September.

• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.842-847
• /
• 1998

Ohmic thawing in combination with conventional water immersion thawing was investigated. Frozen meat chunks $(10{\times}10{\times}10{\;}cm)$ were immersed in a water reservoir $(12{\times}12{\times}12{\;}cm)$ which temperature was maintained at $10^{\circ}C{\;}or{\;}20^{\circ}C$, and were positioned between two stainless-steel electrodes $(10{\times}10{\;}cm)$ having no direct contact with the samples. Alternating current $(60{\;}V{\sim}210{\;}V)$ at various frequency $(60{\;}Hz{\sim}60{\;}kHz)$ was used to generate internal heat by the electrical resistance. When the frequency was fixed to 60Hz, thawing time was reduced as the voltage increased. Frequency changes gave no significant effect on thawing time. Ohmically-thawed samples treated with lower voltage showed lower drip loss and higher water holding capacity.

• Economic and Environmental Geology
• /
• v.37 no.3
• /
• pp.347-354
• /
• 2004

We report the petrographic and petrochemical results on the rocks which have been classified as hornfelsic sandstones or mudstones of the Gyeongsang Group in Wolseong Area, part of Choyang Geologic Sheet (Tateiwa, 1924) and discuss its origin. The rocks consist of alternating layers with dark. fine-grained and bright, coarse-grained but don't have any clues of thermal alteration such as hornfels. The rocks are composed of quartz, feldspar and rock fragments of volcanic origin. The overall geochemical characteristics of the rocks indicate that the rocks have mainly rhyolitic composition with 64.5-72 wt% SiO$_2$ and are similar to the trend of Cretaceous and Tertiary volcanic rocks around this area. On the contrary, the geochemical characteristics of rocks are distinguished from those of Lower Cretaceous Sindong and Mayans mudrocks in the Gyeongsang Basin. We re-name the rocks as rhyolitic tuffite.

• 한국방재학회:학술대회논문집
• /
• 2008.02a
• /
• pp.799-802
• /
• 2008

General behaviors based on hydraulic characteristics of natural streams and channels have been recently analyzed and developed via various numerical models. However in the states of natural hydraulics, an experimental research must be performed simultaneously with the mathematical analysis due to effects of hydraulic properties such as meander, sediment, and so on. In this study based on 2-D advection-dispersion equation, flow and tracer experiments were performed in the S-curved meandering laboratory channel with a rectangular cross-section. The channel was equipped with instrument carriages which was equipped with an auto-traversing system to be used with velocity measuring sensors throughout the depth and breadth of the flow field. To measure concentration distribution of the salt solution was adjusted to that of the flume water by adding methanol and a red dye (KMnO4) was added to aid the visualization of the tracer cloud, the tracer was instantaneously injected into the flow as a full-depth vertical line source by the instantaneous injector and the initial concentration of the tracer was 100,000 mg/l. The secondary current as well as the primary flow pattern was analyzed to investigate the flow distribution in the meandering channels. The velocity distribution of the primary flow for all cases skewed toward the inner bank at the first bend, and was almost symmetric at the crossovers, and then shifted toward the inner bank again at the next alternating bend. Thus, one can clearly notice that the maximum velocity occurs taking the shortest course along the channel, irrespective of the flow conditions. The result of the tracer tests shows that pollutant clouds are spreading following the maximum velocity lines in each cases with various mixing patterns like superposition, separation, and stagnation of pollutant clouds. Flow characteristics in each cases performed in this study can be compared with tracer dispersion characteristics with using evaluation of longitudinal and transverse dispersion coefficients(LDC, TDC). As expected, LDC and TDC in meandering parts have been evaluated with increasing distribution and straight parts have effected to evaluate minimum of LDC and TDC due to symmetric flow patterns and attenuations of secondary flow.

• Journal of the Korean Geotechnical Society
• /
• v.33 no.2
• /
• pp.27-34
• /
• 2017

Various earth retaining wall methods were used on the domestic construction sites and a cast in place pile (C.I.P) method was mostly applied at deep excavation. Because of a lot of shortcomings in the C.I.P method, a new method using PHC-W earth retaining wall was developed. The earth retaining wall method using PHC-W piles has a lot of advantages including that it is safer than other earth retaining wall methods due to uniform quality and high rigidity. PHC-W was designed to effectively resist lateral earth pressure by alternating cross section of PHC pile. And increment of bending moment and shear strength were verified through KS F 4306 tests, and were increased by 42% and 98% more than KS standards.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.276-279
• /
• 2004

Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2006.06b
• /
• pp.271-278
• /
• 2006

We used polymers of alternating cationic and anionic nature to build up shells on fiber surfaces, strengthen the worn-out fibers and improve paper properties made from such fibers. OCC and ONP pulps were either dipped or salted out in the cationic polyallylamine, polyacrylamide and starch solutions. After centrifugal drying, these were followed by treatments in anionic polyacrylic acid, poly-acrylamide, and starch solutions, respectively. The shell-enhanced fibers were formed into handsheets and their physical properties evaluated. The results show that building multiple shells on worn-out fiber surfaces can strengthen the fibers and paper. The simpler and more practical impregnation-centrifuging treatment provided the desired effects, whereas salting out the polymers produced somewhat superior fibers. The latter process, were impractical, however. The first pair of polymeric shells imparted marked strength improvement, whereas later layers had diminishing efficacies. Overall, the methods can improve fiber quality, attaining paper strength requirements without resorting to expensive measures. Alternate cationic polymer and filler powders were also deposited on fiber surface based on the micriparticle system in an anticipation of stiffness gains. Platy minerals, such as montmorillonite, bentonite, sericite, clay and talc were added following cationic PAM. After dewatering of polymer-pigment shelled fiber of one to 3 pairs of layers, handsheets either calendered or uncalendered were evaluated. The results indicate that regardless of calendaring, stiffness of the handsheets did not improve appreciably while certain other strength properties showed gains. We also attempted the novel starch gel filler addition method wherein tapioca starch and filers (PCC, sericite or clay) were mixed at high solids content of 50% and cooked until gelatinized. The filled handsheets were dried under various conditions and then tested for their properties. Improvements in strengths of modified filled paper were observed.

• Polymer(Korea)
• /
• v.35 no.6
• /
• pp.531-536
• /
• 2011

Homopolymer distribution in block copolymer/homopolymer blends was investigated as a function of homopolymer concentration and homopolymer molecular weight. The deuterated poly(methyl methacrylate) or polystyrene was blended with a deuterated polystyrene-poly(methyl methacrylate) diblock copolymer up to a concentration of 20 wt%. Samples were characterized by small-angle X-ray scattering (SAXS), neutron reflectivity and transmission electron microscopy. The block copolymer with a thin-film geometry formed alternating lamellar microdomains oriented parallel to the substrate surface. By adding the homopolymer, the microdomain structure was significantly disturbed. As a consequence, a poorly ordered morphology appeared when the homopolymer concentration exceeded 15 wt%. Increasing the homopolymer concentration and/or the homopolymer molecular weight caused the microdomains to swell less uniformly, resulting in segregation of the homopolymer toward the middle of the microdomains.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2019.05a
• /
• pp.212-212
• /
• 2019

일반적으로 도시 우수 관망의 계획에 대부분 합리식 등을 이용하여 첨두유량만 검토하였기 때문에 설계 강우의 시간 분포 방법은 고려되지 않았다. 하지만 최근에는 집중 호우로 인한 침수 피해가 많이 발생함에 따라 하수도 시설물들의 연계를 통한 침수 해결이 요구되었고, 첨두 유출량뿐만 아니라 홍수 수문 곡선도 산정 할 수 있는 강우-유출 모형을 설계에 도입해야 할 필요성이 제기되었다. 그러나 현재까지 우수 관망 등 하수도 시설물에 대한 분석에 적합한 강우의 시간 분포 방법은 제시되지 않고 있다. 이에 본 연구는 실무적으로 널리 이용되고 있는 Huff 4분위 방법과 중 소규모 배수 시설물의 계획에 합리적이라고 알려져 있는 ABM(alternating block method) 방법을 비교 검토하여 도시 우수 관망 해석에 적합한 강우의 시간 분포 방법을 제시하는 것에 목적이 있다. 이를 위해 동해 기상 관측소의 관측 강우자료를 이용하여 강우-빈도 해석을 수행하였고, 다양한 유역 규모에 대한 적용을 위해 임의의 13개 유역을 대상으로 SWMM을 이용하여 홍수량을 분석하였다. 도시 유역의 우수 관망 계획에 적합한 확률 강우의 시간 분포 방법을 결정하기 위해 실제 강우 현상의 재현성, 소규모 배수 구역에 대한 첨두 홍수량 산정의 정확성, 우수 관망의 연속성을 고려한 계획의 3가지 관점에 대하여 검토하였다. 우선, 실제 강우 현상의 재현에 있어서 실제의 시간 최대 강우량의 발생분위가 대부분 강우의 지속기간 중 40~50% 사이에 위치하는 것을 감안할 때, ABM의 시간 분포 형태와 유사한 것으로 검토되었다. 두 번째 첨두 홍수량 산정의 정확성 면에서는 시간 단위 자료를 이용하여 유도되어 시간 단위 이하의 지속기간에 대한 확률 강우량 산정에 불확실성이 큰 Huff 방법보다는 ABM에 의한 시간분포 방법이 보다 적절한 것으로 분석되었다. 세 번째로 우수 관망의 연속성을 고려한 계획에서는 소규모 배수 구역 내에 존재하는 다수의 관거를 동시에 고려해야 하는 도시 우수 관망의 특성 상, 동일 지속기간의 확률 강우량에 대한 시간 분포를 적용하는 것이 합리적이다. 이에 배수 면적별로 임계 지속기간이 상이한 Huff 방법보다는 홍수량이 수렴하는 ABM의 24시간 시간 분포를 이용하는 것이 적용에 유리한 것으로 판단되었다. 본 연구의 결과는 합리적인 도시 우수 관망 설계 기술을 구현하는데 기여할 수 있을 것으로 판단된다.