• Journal of Advanced Marine Engineering and Technology
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• 제27권4호
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• pp.520-525
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• 2003

This article provides a dynamic modeling methodology of engines to be accurate with a small number of degrees of freedom for an active vibration control using a top bracing. First. a finite element (FE) model for the engine structure is constructed so that the size of model is as small as possible where the dynamic characteristics of engine are ensured. Second. a technique is studied to obtain the exact mass and stiffness matrices of the FE model. The size of matrices from the FE model is still too large to apply. Finally, a model reduction is. therefore. conducted to make an appropriate dynamic model for designing and simulating a top bracing. In this article, a dynamic model of a large 9 cylinder engine is constructed and reviewed by comparing its natural frequencies and steady state reponses with those of experimental data provided by manufacturer.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.251-255
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• 2012

Structural intensity has been mainly utilized to identify vibration energy flow in a vessel. In this paper, the structural intensity of a shuttle tanker subjected to H-moment of the main engine was calculated using a finite element model. From the analysis, it was found that the top-bracing elements, which support the main engine onto the hull structure to prevent the excessive transverse vibration of the main engine, play the role of the dominant path and sink for vibration energy flow from the main engine. Therefore, the structural intensity was controlled by the modification of stiffness and damping characteristics of the top-bracing elements. As a result, it is observed that the transverse vibration level at the center of navigation bridge deck decreased after the control of structural intensity.

• 한국약용작물학회지
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• 제20권6호
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• pp.447-453
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• 2012

This study was conducted to determine the contents of phenolic compounds and astragalosides in Astragalus membranaceus. Between the phenolic compound groups, flavonoids compounds (51.13%) had higher average concentrations than the phenolic acids groups. Among the 30 phenolic compounds, quercetin ($353.11{\mu}g\;g^{-1}$) provided the highest concentrations. According to different cultivation year, 3-year-cultivated Astragalus ($2612.57{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic compounds. According to different harvest days, 6/5 harvesting Astragalus ($2615.80{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic acids. Comparison between the top and subterranean parts of harvested Astragalus plants cultivated for 2 years, 3 years, and 5 years showed big difference of total phenolic compounds in concentrations. Further, the top part had higher amounts of the total phenolic compounds than the subterranean part among all Astragalus. This tendency was similar to those of the top root and lateral root. The concentration of the phenolic compounds in the top root was higher than that of the lateral root.

• 산업융합연구
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• 제12권1호
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• pp.1-23
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• 2014

This study is to research parents' awareness of the child-care quality and their loyalty toward the day care center, targeting parents who are the most important role in infant development. Therefore the purpose of this study is to find out the top priorities of the day care center services that parents recognize and its influence on the parents' loyalty to the center.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.457-458
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• 2006

Transparent metal cathodes using Ca/Ag, Ba/Ag double layers have been fabricated to investigate its optical transmission. The transmission spectra show that Ca/Ag and Ba/Ag double layers result in higher transmittance compared to Ag single layer. The Ba/Ag double layer shows over 80% transmittance at 400 nm and 70% at 700 nm. The electroluminescence efficiency of fluorescent TEOLED using Ba/Ag transparent metal cathode was 10 ~ 15 cd/A.

• Asian-Australasian Journal of Animal Sciences
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• 제33권8호
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• pp.1252-1264
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• 2020

Objective: To effectively utilize crop by-product resources to address the shortage of animal feed during the dry season in Africa, the community of natural lactic acid bacteria (LAB) of corn stover and sugarcane tops and fermentation characteristics of silage were studied in Mozambique. Methods: Corn stover and sugarcane tops were obtained from agricultural field in Mozambique. Silage was prepared with LAB inoculant and cellulase enzyme and their fermentation quality and microbial population were analyzed. Results: Aerobic bacteria were the dominant population with 10⁷ colony-forming unit/g of fresh matter in both crops prior to ensiling, while 10⁴ to 10⁷ LAB became the dominant bacteria during ensiling. Lactobacillus plantarum was more than 76.30% of total isolates which dominated silage fermentation in the LAB-treated sugarcane top silages or all corn stover silages. Fresh corn stover and sugarcane tops contain 65.05% to 76.10% neutral detergent fiber (NDF) and 6.52% to 6.77% crude protein (CP) on a dry matter basis, and these nutrients did not change greatly during ensiling. Corn stover exhibits higher LAB counts and water-soluble carbohydrates content than sugarcane top, which are naturally suited for ensiling. Meanwhile, sugarcane tops require LAB or cellulase additives for high quality of silage making. Conclusion: This study confirms that both crop by-products contain certain nutrients of CP and NDF that could be well-preserved in silage, and that they are potential roughage resources that could cover livestock feed shortages during the dry season in Africa.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.815-818
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• 2016

전방 추돌 경보 시스템(FCWS) 및 차선 이탈 경보 시스템(LDWS)은 운전자 보조 시스템(ADAS)의 중요한 요소이다. 차량 전방 카메라를 이용한 차선 이탈 경보 시스템은 일반적으로 취득한 영상에서 직선 형태의 차선이나 RANSAC 등을 이용한 곡선을 추적하여 차량의 중심과 비교하게 된다. 이러한 알고리즘은 넒은 범위의 차선이 요구되고 곡선에 취약한 약점이 있다. 본 논문에서는 Top-view 공간에서 현재 차량을 기준으로 차선 이탈 여부를 검사하는 알고리즘을 제시한다. 이 알고리즘은 좁은 범위의 차선으로도 차량 이탈 여부를 검사할 수 있으며 잡음에 영향을 거의 받지 않는 결과를 보여준다.

• 한국환경보건학회지
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• 제36권3호
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• pp.236-246
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• 2010

In preparative anti-corrosive coating experiments, polyaniline was obtained by reacting an oxidizing agent with the monomer aniline. Further, the primer coating was prepared using a variety of widely-used materials such as urethane resin. For the top coating, epoxy resin and acrylic urethane resin were used. Characteristics of the coatings were assessed according to KS and ASTM specifications, and the structure of the polyaniline was characterized using FT-IR and TGA. For analysis of anti-corrosive properties in salt-spray experiments, measurements of the oxidation state of iron and surface atomic analysis were conducted using XPS and SEM-EDX. Unlike general anti-corrosive coatings which exhibit anti-corrosive effects only as a primer coating, the anti-corrosive coatings using polyaniline as the anti-corrosive pigment showed a marked synergistic effect with the top coatings. In other words, the top coatings not only produce a fine view effect, but also increase, through interaction with the primer coatings, the resistance to diffusion of corrosive factors from the external environment. It was also found that, unlike the heavy metal oxide-forming layer of the passive barrier alone, the polyaniline anti-corrosive pigment oxidized iron at the interface with the iron substrate to form a passive barrier in the oxidic layer, and itself formed a potential barrier layer with anti-corrosive factors from the external environment. Although the passive layer was damaged, the damaged area did not become completely oxidized iron; on the contrary, it showed a tendency to reduction. This can be interpreted such that a passive layer is formed again on the damaged area, and that at the same time there is a tendency to self-healing.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.7-10
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• 2003

Samsung SDI has developed a full color 5.0" WVGA AMOLED display with top emission and a super fine pitch of 0.1365mm(l86ppi), the world's highest resolution OLED display ever reported to date. Scan driver circuits and demux circuit were integrated into the display panel, using low temperature poly-Si TFT CMOS technology, and data driver circuit were mounted using COG chips. Peak luminescence was greater than 300cd/ $m^2$ with power consumption of 500mW with 30% of the pixels on illuminated.

• ETRI Journal
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• 제33권6호
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• pp.887-896
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• 2011

We investigated the effects of a gate dielectric and its solvent on the characteristics of top-gated organic field-effect transistors (OFETs). Despite the rough top surface of the inkjet-printed active features, the charge transport in an OFET is still favorable, with no significant degradation in performance. Moreover, the characteristics of the OFETs showed a strong dependency on the gate dielectrics used and its orthogonal solvents. Poly(3-hexylthiophene) OFETs with a poly(methyl methacrylate) dielectric showed typical p-type OFET characteristics. The selection of gate dielectric and solvent is very important to achieve high-performance organic electronic circuits.