• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.3073-3082
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• 1993

A magnetically suspended robot joint is developed, which is free of dust and oil generation. Two radial bearings consisting of cone-shaped magnet cores control the rotor motion in the axial and radial directions. A linearized dynamic model is developed for active control of the magnetic bearing system. The control algorithm is constructed such that the axial displacement of the joint is controlled by radial control current to the pairs of facing radial bearings. The stability and control performance is tested through numerical simulation based on the nonlinear model. Experiments are also performed to verify the theoretical development.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.4
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• pp.459-469
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• 2005

In recent years, concerns have been growing globally regarding greenhouse gases. Open burning of biomass causes emission of a number of greenhouse and other gases and substances. This paper studied an analysis on the characteristics of four types of biomass using duel type cone calorimeter. Cone calorimeter is widely used for assessing combustibility of materials in Europe. As a result, we evaluated several characteristics of biomass, such as heat released rate, smoke production rate, CO, $CO_2$ production and mass loss rate, and so on. $CO_2$ is currently responsible for over $60\%$ of the enhanced greenhouse effect, and may be the most important contributor to future. $CO_2$ production for biomass in the range of $1.74\~1.99kg/kg$ is similar to previous research conducted by Bhattacharya et al. (2002a).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1055-1056
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• 2010

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.23 no.4
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• pp.351-365
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• 2019

This article presents a new approach for conformal flattening with optimal cone singularity. The algorithm here takes an optimal control for selecting optimal cones and uses the Ricci flow to force the flattening. This work is considered as a modification to the work of Soliman et al. [1] in the sense that they make use of the Yamabe equation for the flattening, which is an approximation of the Ricci flow. We present a numerical algorithm based on the optimal control with the mathematical background. Several numerical results validate that our method is optimal in total cone angle and usage of the Ricci flow ensures the conformal flattening while selecting optimal cones.

• ETRI Journal
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• v.36 no.6
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• pp.942-952
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• 2014

This paper presents a novel test point insertion (TPI) method for a pseudo-random built-in self-test (BIST) to reduce the area overhead. Recently, a new TPI method for BISTs was proposed that tries to use functional flip-flops to drive control test points instead of adding extra dedicated flip-flops for driving control points. The replacement rule used in a previous work has limitations preventing some dedicated flip-flops from being replaced by functional flip-flops. This paper proposes a logic cone analysis-based TPI approach to overcome the limitations. Logic cone analysis is performed to find candidate functional flop-flops for replacing dedicated flip-flops. Experimental results indicate that the proposed method reduces the test point area overhead significantly with minimal loss of testability by replacing the dedicated flip-flops.

• Korean Journal of Poultry Science
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• v.46 no.4
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• pp.305-312
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• 2019

This study investigated the effect of diet supplementation with pine cone extracts (pine cone ethanol extract: PCEE; pine cone ethanol-hexane extract: PCEHE) on growth performance, digestive organ characteristics and intestinal microbiota of semi-broiler. Twenty two-weeks-old semi-broilers were divided into four dietary groups (n=5/group; control(-): no antibiotics and pine cone extracts; control(+): 2% antibiotics [20 g/kg basal diet]; PCEE: 2% PCEE [20 g/kg basal diet]; PCEHE: 2% PCEHE [20 g/kg basal diet]). Chicks were reared and their diets were supplemented accordingly for 16 days. Final weight, weight gain and feed intake were lowest (P<0.05) in semi-broilers whose diet was supplemented with pine cone extracts, but both PCEE and PCEHE groups showed lower (P<0.05) feed conversion ratios compared to the control(-) group. Gizzard and small intestinal weight were also lower (P<0.05) in both PCEE and PCEHE groups than in the control(-) group. Intestinal length and villus height were similar for all treatments. Furthermore, cecal microbiota was not improved by PCEE and PCEHE supplementation. These findings suggest that diet supplementation with pine cone extracts improves the feed conversion ratio and affects the digestive organ weight of semi-broilers.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.72-73
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• 2005

This study was carried out to investigate the effects of extracts supplements of pine nut cone on the broiler performance and the cholesterol content, the lipid oxidation of serum and meat of broilers. The control group was fed a common basal diet without antibiotics and the treatment group were fed a common basal diet with extracts of pine nut cone of 500ppm(T1), illite 1% +extracts of pine nut cone of 500ppm(T2), pine nut cone powder of 2.5%(T3) for 5 weeks. The weight gain and the feed intake were significantly higher treatment than control. The cholesterol content of serum was significantly decreased in T1, T2 group. The breast was also significantly decreased in T1, T2 group. The thigh was not different among treatment, but the cholesterol content of serum was significantly lower in T1, T2 treatment than control. TBARS of the brest and the thigh showed significantly lower than control. POV of the brest and the thigh showed different among treatment, but there were no correlations among treatment.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.199-207
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• 2020

These days, many different types of valves are developed in the industrial area according to their use purpose. Multiple kinds of valves are installed to control a flow and pressure of the pipe conveying fluid. Valves serve as critical roles in land plants such as power plants. The performance of equipment varies depending on valve characteristics. In this study, the internal flow analysis on Cone-type valve is conducted to analyze flow field and secure a value of the flow coefficient Cv. According to the internal flow analysis, when the flow distribution of the middle cross-section of valve was open 100%, flow field was relatively and smoothly taken out. If it was open 50%, flow recirculation region increased and a little complex flow field occurred. Unlike ball valve or butterfly valve, this valve had flow recirculation in its outlet depending on a valve opening amount. Therefore, it was found that there was no flow recirculation in the outlet of Cone-type valve.

• Journal of Drive and Control
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• v.19 no.4
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• pp.77-84
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• 2022

The aims of this study was to estimate transfer force delivered to cone crusher housing and contribution of force transmission. The rock crushing condition caused vibrations in the cone crusher housing, which were experimentally measured, and frequency response functions (FRF) were also found through modal impact tests. Vibration data and frequency response functions were applied to the transfer path analysis (TPA) model. Next, transfer forces delivered to the cone crusher housing were quantified via the TPA method. Contribution of force transfer was also analyzed based on force estimation results. Finally, this study describes basic concepts and components of the TPA method and reviews its applicability to rotating machinery that experiences impact vibrations and forces.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.106-106
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• 2022

The cone of Red Pine (Pinus densiflora), which has been used as a drug in traditional medicine. Its ethyl acetate fraction was reported to exert antioxidant, anti-melanogenesis, and anti-inflammation activites. Apoptosis of hepatic stellate cells (LX-2) is regarding as a potential strategy for alleviation of hepatic fibrosis. We conducted to investigated whether the treatment of cone has a potential to control of some factors related in apoptosis and autophagy in cell signaling pathways. We suggest that the cone induced apoptosis through confirming the expression levels of genes (cPARP, Bcl-XL, Bax, p53, and caspase-3) in LX-2 cells. Also, the cone may regulate autophagy (LC3, p62, Beclin-1, and ATG12). Remarkably, the treatment of cone may affect to formation of autophagosomes in the immunofluorescence image in live cells. These findings suggest that the ethyl acetate fraction from the cone of Red Pine (P. densiflora) may have potential as an alternative therapeutic agent for the alleviation and prevention of liver fibrosis.