• Tribology and Lubricants
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• v.35 no.2
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• pp.123-131
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• 2019

This study characterizes the coastdown performances of two small electric motors supported on high-speed ball bearings (BBs) and gas foil bearings (GFBs), and it predicts their acceleration performances. The two motors have identical permanent magnetic rotors and mating stators. However, the shaft of the GFBs has a larger mass and polar/transverse moments of inertia than that of the BBs. Motor coastdown tests demonstrate that the rotor speed decreases linearly with the BBs and nonlinearly with the GFBs. A simple model for the BBs predicts a constant drag torque and linear decay of speed with time. The test data validate the model predictions. For the GFBs, the hydrodynamic lubrication model predictions reveal that the drag torque increases linearly with speed, and the speed decreases exponentially with time. The predictions agree very well with the test data in the speed range of 100-30 krpm. The boundary lubrication model predicts a constant drag torque and linear decay of speed with time. The predictions agree well with the test data below 15 krpm. Mixed lubrication occurs in the speed range of 30-15 krpm. Rotor acceleration performances are predicted based on the characteristics of deceleration performances. The GFBs require more time to reach 100,000 krpm than the BBs because of their larger shaft polar moment of inertia. However, predictions for the assumed identical polar moment of inertia reveal that the GFBs have a nearly identical acceleration performance to that of the BBs with a motor torque greater than $0.03N{\cdot}m$.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.2
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• pp.66-77
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• 2011

We propose a framework for grouping photographic advertising images that employs a hierarchical indexing scheme based on efficient feature combinations. The study provides one specific application of effective tools for monitoring photographic advertising information through online and offline channels. Specifically, it develops a preprocessor for advertising image information tracking. We consider both global features that contain general information on the overall image and local features that are based on local image characteristics. The developed local features are invariant under image rotation and scale, the addition of noise, and change in illumination. Thus, they successfully achieve reliable matching between different views of a scene across affine transformations and exhibit high accuracy in the search for matched pairs of identical images. The method works with global features in advance to organize coarse clusters that consist of several image groups among the image data and then executes fine matching with local features within each cluster to construct elaborate clusters that are separated by identical image groups. In order to decrease the computational time, we apply a conventional clustering method to group images together that are similar in their global characteristics in order to overcome the drawback of excessive time for fine matching time by using local features between identical images.

• Korean Journal of Cognitive Science
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• v.22 no.4
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• pp.469-494
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• 2011

It is well known that visual objects belonging to the same perceptual category compete for category-specific, limited-capacity attentional resource. However, it remains to be seen how perceptually identical objects interact with each other during visual analyses. Perceptually identical objects might suppress each other as much as categorically identical objects do. Alternatively, they might cooperate to generate a perceptual representation which is long lasting and robust to noise. Such possibilities were tested in the current research with three behavioral experiments using the Stroop task. As results, relative to a single distractor, Stroop interference was diluted by two different distractors of a category while it was enhanced by two perceptually identical distractors (Experiment 1). This redundancy effect disappeared when two different distractors associated with the same response were presented (Experiment 2), and it was not affected by the between- vs. within-hemisphere distractor presentations (Experiment 3). These findings indicate that the redundancy effect of distractors may be mediated by perceptual representations based on hemisphere-independent attentional resources. Overall, the current study supports the hypothesis that Stroop interference is constrained by category-specific attentional resources and further suggests that redundant presentations of a stimulus overcome such attentional constraints by facilitating perceptual processing.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.5
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• pp.1035-1041
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• 2017

In magnetic resonance-based wireless power transfer (WPT) systems, frequency splitting phenomenon, in which power transfer efficiency (PTE) decreases seriously as resonators are close to each other, is the problem that we should address for reliable power transfer in short distance. In this paper, we present WPT systems using an equivalent circuit model and analyze PTE and marginal coupling coefficient ($k_{split}$) where the frequency splitting occurs. In addition, we perform circuit-level simulations using Advanced Design System, and show that the achievable PTE is different for the structures of resonators when k>$k_{split}$. We confirm that higher PTE can be ensured as k increases in the case of identical resonators, while PTE is degraded as k increases in the case of non-identical resonators. Therefore, in short distance, in which k>$k_{split}$, it is more efficient for achieving reliable PTE to use identical resonators rather than non-identical resonators.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.458-465
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• 2021

Tubulysins are a group of bioactive secondary metabolites from myxobacteria exhibiting strong anticancer activity against various cancer cell lines. In this study, we describe the identification of putative tubulysin biosynthetic gene clusters (tubA~tubF) in the genome sequences of two tubulysin-producing myxobacterial strains, Archangium gephyra MEHO_002 and MEHO_004. The inactivation of the putative tubulysin biosynthetic genes resulted in a tubulysin-production defect. The DNA sequences of the A. gephyra MEHO_002 and MEHO_004 tubulysin biosynthetic genes were 97% identical, and the amino acid sequences of the encoded proteins shared a similarity of 97-100%. The nucleotide sequences of the tubulysin biosynthetic gene clusters in MEHO_002 and MEHO_004 were 86% identical to that in Cystobacter sp. SBCb004 known as a tubulysin-producing myxobacterium, and the organization of the clusters was identical except for the lack of a tubZ gene in the clusters in MEHO_002 and MEHO_004. The amino acid sequences of the proteins encoded by each gene were 88-97% similar to those encoded by SBCb004, and the domain compositions of the proteins were also identical.

• The Journal of Korean Philosophical History
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• no.41
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• pp.185-222
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• 2014

Nog-Moon Yim Seong-Joo(녹문 임성주) is a philosopher of late Choseon Dynasty of the 18th Century. He concluded that the debates between the school of Ho and that of Rack originated from the seclusion of Li(理) and Ki(氣), and theorized the new Li and Ki theory according to his own perspective. The prime point of Nog-Moon's Philosophy is said to be Li-Ki dongshil(理氣同實), Mind and Nature ilchi(心性一致) ; he proves his prime potints based on his pure and clean Ki substance. Thus Li-Ki is reduced to monism from dualism, and Mind-Nature(心 性) is reduced to mind. Since the basis of the existence of Mind is Ki(氣), Nog-moon's theory of Substance is concluded to be Ki-monism. Nog-Moon presents his great philosophy of Ki monism suggested by Jeong Myeong-Do's monistic methodology; he explains the universality of Substance and the diversity of Phenomenon with the logical structure of ilwonbunsu(一原分殊). The characteristics of Nog-Moon's philosophy is that ilwon(一原) and bunsu(分殊) are bonnyeon(本然) identical, which means Substance and Function(體用) are identical, or bonmalilchi(本末一致). It means Mind and Nature are bonnyeon(本然) identical, Ki and Mind and Nature are identical. With the expression of seongrihak (性理學) Gijil(氣質) is not different from bonnyeon(本然). Therefore 1 define the philosophy of Nog-Moon had been built on the context of a sage.

• Animal Bioscience
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• v.36 no.6
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• pp.943-952
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• 2023

Objective: For decades, LYD ([Landrace×Yorkshire] ♀×Duroc ♂) pigs are the most commonly-used commercial breed for meat production in Korea. Recently, due to the increasing demand for premium pork, the National Institute of Animal Science (Korea) has synthesized a novel pig breed named Woori Heukdon (WHD). This study aimed at comparing the carcass traits, meat yield and quality characteristics between the LYD and WHD pigs under identical rearing condition. Methods: The WHD and LYD pigs (n = 15 each) were reared under identical conditions and fed the same commercial diet until reaching recommended market weight (100 to 120 kg). After slaughter, the carcasses were evaluated for traits and meat yield, and the meat quality was assessed on shoulder butt and belly cuts. Results: Although no significant differences (p>0.05) occurred in slaughter weight between two pig types, WHD had a lower meat yield (by about 6 kg corresponding to approximately 7%) compared to the LYD pigs (p<0.05). The WHD had a higher fat content (by 4.26% and 13.52% in the shoulder butt and belly, respectively) compared to those of LYD pigs (p<0.05). The WHD meat showed a lower cooking loss and higher a* (redness) value (p<0.05). The WHD belly had a significantly (p<0.05) higher oleic acid content and concentrations of nonanal, octanal and decanal associated with fatty odor while, the LYD meat had a higher number of pyrazines associated with roasty odor. Regarding sensory quality, higher flavor, juiciness, and acceptability higher scores were given for the WHD meat than for the LYD meat (p<0.05). Conclusion: Under identical rearing conditions the WHD exhibited a better meat quality and sensory properties. However, the use of this diet resulted in a high fat level that may be associated with high trimming loss for the WHD.

• Journal of the Chungcheong Mathematical Society
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• v.16 no.1
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• pp.73-79
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• 2003

A subgroup S(X, ${\gamma}$) of the group of automorphisms of a universal minimal transformation group is introduced and a necessary and sufficient condition for two subgroups to be identical is obtained.

• Proceedings of the Korea Society of Design Studies Conference
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• 2004.10a
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• pp.202-203
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• 2004

• Communications of the Korean Mathematical Society
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• v.12 no.2
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• pp.257-267
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• 1997

It is shown that if S is a positively expansive endomorphism on a one-sided mixing SFT (X,T), then (X,S) is conjugate to a one-sided mixing SFT, and the Parry measures of (X,T) and (X,S) are identical.