• Structural Engineering and Mechanics
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• 제42권2호
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• pp.269-289
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• 2012

Free vibration and dynamic responses of piles semi-rigidly connected with the superstructures are investigated. Timoshenko beam theory is employed to characterize the pile partially embedded in a two-parameter elastic foundation. The formulations for the method of reverberation-ray matrix (MRRM) are then derived to investigate the dynamics of the pile with surface cracks, which are modeled as massless rotational springs. Comparison with existent numerical and experimental results indicates the proposed method is very effective and accurate for dynamic analysis, especially in the high frequency range. Finally, the effects of some physical parameters on the natural frequencies, frequency responses and transient responses of the piles are studied.

• ETRI Journal
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• 제40권2호
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• pp.246-256
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• 2018

A spatial augmented reality (SAR) system enables a virtual image to be projected onto the surface of a real-world object and the user to intuitively control the image using a tangible interface. However, occlusions frequently occur, such as a sudden change in the lighting environment or the generation of obstacles. We propose a robust object tracker based on a multithreaded system, which can track an object robustly through occlusions. Our multithreaded tracker is divided into two threads: the detection thread detects distinctive features in a frame-to-frame manner, and the tracking thread tracks features periodically using an optical-flow-based tracking method. Consequently, although the speed of the detection thread is considerably slow, we achieve real-time performance owing to the multithreaded configuration. Moreover, the proposed outlier filtering automatically updates a random sample consensus distance threshold for eliminating outliers according to environmental changes. Experimental results show that our approach tracks an object robustly in real-time in an SAR environment where there are frequent occlusions occurring from augmented projection images.

• 한국임상수의학회지
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• 제16권2호
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• pp.413-416
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• 1999

To establish feline electroacupuncture anesthesia, 5 cats (mixed, 1 month old, 0.4~0.5 kg, female) were examined in the present study. The acupoints used for feline electroacupuncture anesthesia were Tian-ping and Bai-hui. After perpendicular insertion of needle to Tian-ping and Bai-hui, respectively, positive electrode was connected at Tian-ping and negative electrode was connected at Bai-hui, respectively, Electric condition was 3 V and 30 Hz. To examine the effect of electroacupuncture anesthesia, laparotomy (5 heads)was applied. The pain of the body surface and the extremities excluding the tail was not found, and the induction time of electroacupuncture anesthesia was approximately 1 minute. As for the reactions with electroacupuncture anesthesia, the head part was directed to backward, blepharoreaction was mild and the consciousness was vivid. The class of anesthesia effect was excellent in 4 heads and was poor in 1 head. The pain was not observed and bleeding was comparatively small volume during surgery in excellent group.

• Journal of applied mathematics & informatics
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• 제13권1_2호
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• pp.201-215
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• 2003

A map is a connected topological graph $\Gamma$ cellularly embedded in a surface. For any connected graph $\Gamma$, by introducing the concertion of semi-arc automorphism group Aut$\_$$\frac{1}{2}$/$\Gamma$ and classifying all embedding of $\Gamma$ undo. the action of this group, the numbers r$\^$O/ ($\Gamma$) and r$\^$N/($\Gamma$) of rooted maps on orientable and non-orientable surfaces with underlying graph $\Gamma$ are found. Many closed formulas without sum ∑ for the number of rooted maps on surfaces (orientable or non-orientable) with given underlying graphs, such as, complete graph K$\_$n/, complete bipartite graph K$\_$m, n/ bouquets B$\_$n/, dipole Dp$\_$n/ and generalized dipole (equation omitted) are refound in this paper.

• 한국CDE학회논문집
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• 제5권2호
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• pp.196-205
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• 2000

This paper proposes a topology-based algorithm for recognizing the passage features using a concept of multi-face hole loop. The Multi-face hole loop is a concetpual hole loop that is formed over several connected faces. A passage feature is recognized in the proposed approach by two multi-face hole loops that constitute its enterance and exit. The algorithm proposed in this paper checks the connectivity of the two multi-face hole loops to recognize passage features. The total number of passage features in a part is calculated from Euler equation and is compared with the number of found passage features to decide when to terminate. To find all multi-face hole loops in a part, this paper proposes an algorithm for finding all combinations of connected faces. The edge convexity is used to judge the validity of multi-face hole loops. By using the algorithm proposed in this paper, the passage features could be recognized effectively. The approach proposed in this paper is illustrated with several example parts.

• Applied Microscopy
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• 제24권4호
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• pp.98-106
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• 1994

The corneal formation of compound eye of Pieris rapae L., which was mostly made during pupal stage, was morphologically investigated with light microscope, scanning electron microscope and transmission electron microscope. The regeneration of the microvilli were found on the surface membranes of corneagen cells and retinular pigment cells of preommatidium after apolysis pupal cuticle. The microvilli were finally differentiated to corneal nipples of the ommatidium. The corneal cuticle was generated on the superficial layer of the preommatidium from corneagen cells and retinular pigment cells. The corneal process was also formed under the cuticular layer from the corneagen cells. The pore canal was appeared within the cuticular layer and connected with the retinular pigment cell as if the root of interommatidial hair was connected. The interommatidial hair was projected randomly among the ommatidial facets and cornal nipple was arrayed regular on the ommatidial facets. The cornea was convex lens and the refracting power by its convex shape was 4 diopter.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.340-342
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• 2005

A sliding mode controller for the grid-connected photovoltaic system has been presented. This controller is constructed from the time-varying sliding surface In order to control the sinusoidal inductor current and solar array power simultaneously. The proposed controller can achieve the tight regulation of current and power under the parameter variation environment.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 추계학술발표대회
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• pp.343-344
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• 2009

The aim in this paper is to show how to extract scalp of a series of brain MR images by using region growing segmentation algorithm. Most researches are all forces on the segmentation of skull, gray matter, white matter and CSF. Prior to the segmentation of these inner objects in brain, we segmented the scalp and the brain from the MR images. The scalp mask makes us to quickly exclude background pixels with intensities similar those of the skull, while the brain mask obtained from our brain surface. We make use of connected threshold method (CTM) and confidence connected method (CCM). Both of them are two implementations of region growing in Insight Toolkit (ITK). By using these two methods, the results are displayed contrast in the form of 2D and 3D scalp images.

• 한국재료학회지
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• 제13권5호
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• pp.297-302
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• 2003

The effects of risering design and alloying element on the formation of defects such as external depression, primary and secondary shrinkage cavity in gray cast iron were investigated. Two types of risering design for the cylindrically step-wise specimen, No. 1(progressive solidification) and No. 2(directional solidification) risering designs, were prepared and five different alloy compositions were casted. In the No. 1 risering design, external depression or primary shrinkage cavity due to liquid contraction was observed in all the specimens from ISO 150 to ISO 350. The primary shrinkage cavity was located right under the top surface or connected to the top surface, and was characterized by smooth surface. Its size increased with an increase in ISO number. However, neither secondary shrinkage cavity nor swollen surface was observed in all the castings. In the No.2 risering design, neither primary shrinkage cavity nor secondary shrinkage cavity was observed in all the specimens due to proper risering design. A swollen surface was also not observed in all the castings with the application of pep-set mold.

• 유통과학연구
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• 제18권10호
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• pp.77-87
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• 2020

Purpose: This study was done to analyze the effect of supervisor-focused impression management behavior of the airline cabin crew on perceived customer empathy. It focused on verifying dual meanings of the crew's emotional expression divided into surface acting and deep acting. Research design, data and methodology: The survey was conducted on cabin crews of two major Korean airlines. The reliability and validity of each variable used in the questionnaire were verified. Then, each hypothesis was analyzed through multiple regression analysis. Results: Firstly, the crew's supervisor-focused impression management behavior had a significant effect only on surface acting of the crew's emotional labor behavior. Among the crew's supervisor-focused IM behaviors, verbal IM behavior had a greater influence on surface acting than non-verbal IM behavior. Secondly, there was no relationship between the crew's supervisor-focused IM behavior and the crew's deep acting. Thirdly, the crew's emotional labor behavior (surface acting & deep acting) had a significant effect on perceived customer empathy. Fourth, the crew's deep acting had a greater influence on perceived customer empathy than surface acting. Conclusions: Cabin crews receive double evaluation from their immediate supervisors and customers. As a result, it was confirmed that the crew's supervisor-focused IM behavior, the crew's emotional labor behavior, and perceived customer empathy were connected process.