• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2019.06a
• /
• pp.84-85
• /
• 2019

MPEG-NNR (Compression of Neural Network for Multimedia Content Description and Analysis) aims to define a compressed and interoperable representation of trained neural networks. In this paper, we present a low-rank approximation to compress a CNN used for image compression, which is one of MPEG-NNR use cases. In the presented method, the low-rank approximation decomposes one 2D kernel matrix of weights into two 1D kernel matrix values in each convolution layer to reduce the data amount of weights. The evaluation results show that the model size of the original CNN is reduced to half as well as the inference runtime is reduced up to about 30% with negligible loss in PSNR.

• Nuclear Engineering and Technology
• /
• v.54 no.4
• /
• pp.1185-1194
• /
• 2022

The maintenance of condenser main pipe is the key to achieve film-forming amine maintenance effectiveness. In this work, oxygen content, pH and temperature of the solution were controlled to simulate the condition of condenser main pipe, and magnetite coated carbon steel sample was prepared by pre-oxidization. CAM was used to characterize the hydrophobicity of film formed samples. Hydrophobic film was formed on pre-oxidized carbon steel samples when octadecylamine concentration reaches 20 mg/kg. SEM, EDS, EIS, and PD were used to characterize the influence of octadecylamine concentration on maintenance effectiveness. It was found that the maintenance effectiveness was enhanced and the corrosion rate was suppressed with the increase of octadecylamine concentration. FIB and TEM were used to detect the adsorbed octadecylamine film thickness founding that octadecylamine adsorbed onto the surface of pre-oxidized carbon steel by multi-layer adsorption mechanism.

• Journal of Surface Science and Engineering
• /
• v.55 no.5
• /
• pp.299-307
• /
• 2022

Gold plating is used as a coating of connector in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. In most cases, internal connection between device and package and external terminals for connecting packaging and printed circuit board are electroless Ni-P plating followed by immersion Au plating (ENIG) to ensure connection reliability. The deposition behavior and film properties of electroless Au plating are affected by P content, grain size and mixed impurity components in the electroless Ni-P alloy film used as the underlayer plating. In this study, the correlation between electroless nickel plating used as a underlayer layer and cyanide-free electroless Au plating using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent was investigated.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.26 no.3
• /
• pp.239-242
• /
• 1981

Soil stamping made plant type of barley prostrated root system developed well in deeper soil layer, the chlorophyll content of leaf high, ethylene production in leaf high and elongation of lower internode inhibited. Overall result was higher grain yield.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.36 no.1
• /
• pp.36-41
• /
• 2023

We investigated the properties of vanadium oxide (VOx) buffer layers deposited by a dual RF magnetron sputtering method under various target powers for inverted organic solar cells (IOSCs). Sputter fabricatged VOx thin films exhibited higher crystallinity with the increase of target power, resulting in a uniform and large grain size. The electrical properties of VOx films are improved with the increase of target power because of the increase of V content. In the results, the performance of IOSCs critically depended on the target power during the film growth because the crystalllinity of the VOx film affects the carrier mobility of the VOx film.

• Proceedings of the KWS Conference
• /
• 2002.10a
• /
• pp.29-37
• /
• 2002

High alloyed stainless steels stand out for a high corrosion resistance due to a protective passive layer which is formed when the content of chromium exceeds 13%. When welding these steels, heat tints arise in the area of the weldment. They may occur from flint yellow to intensive blue in the spectrum depending on the applied welding process and the quality of the backing gas used. Due to their structures, they partly drastically reduce the corrosion resistance of stainless steels so that they may lead to damages of the technical application of welded components. In the following the pitting resistance by different backing gases and the chemical composition of the stainless steel itself are described.

• Korean Journal of Materials Research
• /
• v.22 no.2
• /
• pp.103-109
• /
• 2012

Red-emitting $Eu^{3+}$-activated $(Y_{0.95-x}Al_x)VO_4$ (0 < x $\leq$ 0.12) nanophosphors with the particle size of ~30 nm and the high crystallinity have been successfully synthesized by a hydrothermal reaction. In the synthetic process, deionized water as a solvent and ethylene glycol as a capping agent were used. The crystalline phase, particle morphology, and the photoluminescence properties of the excitation spectrum, emission intensity, color coordinates and decay time, of the prepared $(Y_{0.95-x}Al_x)VO_4:Eu^{3+}$ nanophosphors were compared with those of the $YVO_4:Eu^{3+}$. Under 147 nm excitation, $(Y_{0.95-x}Al_x)VO_4$ nanophosphors showed strong red luminescence due to the $^5D_0-^7F_2$ transition of $Eu^{3+}$ at 619 nm. The luminescence intensity of $YVO_4:Eu^{3+}$ enhanced with partial substitution of $Al^{3+}$ for $Y^{3+}$ and the maximum emission intensity was accomplished at the $Al^{3+}$ content of 10 mol%. By the addition of $Al^{3+}$, decay time of the $(Y,Al)VO_4:Eu^{3+}$ nanophosphor was decreased in comparison with that of the $YVO_4:Eu^{3+}$ nanophosphor. Also, the substitution of $Al^{3+}$ for $Y^{3+}$ invited the improvement of color coordinates due to the increase of R/O ratio in emission intensity. For the formation of transparent layer, the red nanophosphors were fabricated to the paste with ethyl celluloses, anhydrous terpineol, ethanol and deionized water. By screen printing method, a transparent red phosphor layer was formed onto a glass substrate from the paste. The transparent red phosphor layer exhibited the red emission at 619 nm under 147 nm excitation and the transmittance of ~80% at 600 nm.

• The Korean Journal of Ecology
• /
• v.17 no.3
• /
• pp.277-286
• /
• 1994

The contents of major elements were determined in current-year and previous-year needles and fine roots of pitch pine (Pinus yzgida) at 33 sites in Seoul and its vicinity. Contrary to Ca and Al in needles, N, P, Mg and K contents in current-year needles were higher than those in previous-year needles. The N, P, K and Al contents in current-year needles in Seoul were not significantly different from those in rural areas. In contrast, Ca and Mg contents in needles in Seoul were significantly lower than those in suburbs and rural areas. The N /Ca and N /Mg ratios in needles in urban Seoul were higher than those in rural areas. Mg contents in fine roots in soil of 0-5 cm depth increased along with distance from the center of Seoul, while Al contents in fine root in soil of 5-10 cm depth decreased along with distance from the center of Seoul. Al contents in fine roots in soil layer in Seoul and suburbs were higher than those in rural areas. Al contents in fine roots in litter layer were 1 /3 - 1 /2 times lower than those in soil layer for all areas. A1 content in fine roots in deep soil was higher than that in top soil. Therefore growth decline of pitch pine in Seoul and suburbs was thought to be caused by Ca and Mg deficiency in plant tissues and Al toxicity to fine roots. Abnormal vertical distribution of fine roots of pitch pine in Seoul and its vicinity were interpreted as the result of growth reduction of fine roots by Al toxicity in deep layer of acid soil.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.4
• /
• pp.659-664
• /
• 1996

The amount and characteristics of pectin in the albedo and flavedo layers of the citrus peels, and those of the pulp were investigated. Alcohol insoluble solid(AIS) content was the highest in albedo layer(18.1%), and the lowest in pulp(5.7%). The pulp and the albedo layer showed a potential pectin sources as containing pectins of 40.5% and 35.2% of the total polysaccharides of the pulp and the albedo layer, respectively. Total pectin contents were about 30% of the AIS and showed comparatively constant values among the byproducts. Hydrochloric acid soluble pectin contents were the hightest in the flavedo layer, 14.0%, and the lowest in the pulp, 4.4%. Over 90% of the total pectin could be extracted after 60min with 0.05N HCI at $85^{\circ}C.$ Microwave treatment reduced the extraction time significantly ; a comparable extraction yield was acquired after 10min with microwave treatment. The degree of esterification of the extracted pectin also increased with microwave treatment. Neutral sugars in the hydrolysate of the pectin were rhamnose, arabinose, galactose, glucose and xylose. No differences in molecular weight distribution of the pectin were found between the albedo and flavedo layers. Pectin of the pulp showed different molecular weight distribution from that of the peels.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.24 no.3
• /
• pp.285-293
• /
• 2016

The high velocity oxygen fuel(HVOF) thermal spray is a kind of surface modification techniques to produce the sprayed coating layer. This process is to form the coating layer after spraying the powder to molten or semi-molten state by the ultra-high speed at the high-temperature heat source and conflicting with a substrate. The efficiency of thermal spraying is dropped, however, because the semi-molten powder in a spray process become a factor that degrades the mechanical property by the formed pore within the coating layer. Therefore, it is necessary to melt completely the thermal spray powder in order to produce the coating layer with an optimal adhesive force. In this study, to improve the wear resistance, corrosion resistance and heat resistance, the plungers of high-speed and ultra-high pressure reciprocating hydraulic pumps used in ironworks are manufactured with STS $420J_2$ and are coated by the powders of WC-Co-Cr and WC-Cr-Ni including the WC of high hardness using a HVOF thermal sprayer developed in this laboratory. These are called by the surface-modified plungers. The surface roughness, hardness, and surface and cross-sectional microstructure of these two surface-modified and conventional ceramic plungers are measured and compared before operation with after operation for 100 days. It is found that the values of centerline average surface roughness and maximum height for conventional ceramic plunger are 9.5 to 10.8 and 5.2 to 5.7 times higher than those of surface-modified ones coated by WC-Co-Cr and WC-Cr-Ni because the fine tops and bottoms on surface roughness curve of conventional ceramic plunger are approximately 100 times higher than those of surface-modified ones. In addition, the pores and scratches in the surface microstructure are considerably formed in the order of conventional ceramic, WC-Cr-Ni and WC-Co-Cr surface-modified plungers. The greater the WC content of high hardness powder is less the change in the plunger surface.