• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.41.3-42
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• 2016

New CCD photometric observations of GX Aur have been made between 2004 and 2015. Our light curves are the first ever compiled and display the variable O'Connell effect. The light variations are satisfactorily modeled by including time-varying cool-spots on the component stars. Our light curve synthesis indicates that the eclipsing pair is an A-type contact binary with parameters of i = 81.1 deg, ${\Delta}T=36K$, q = 0.950 and f = 46%. Including our 25 timing measurements, a total of 83 times of minimum light spanning about 66 yr were used for a period study. It was found that the orbital period of GX Aur has varied due to two periodic oscillations superposed on an upward-opening parabolic variation. The long-term period increase rate is deduced as $+9.636{\times}10^{-10}d\;yr^{-1}$, which can be produced as a mass transfer from the secondary star to the primary at a rate of $3.136{\times}10^{-6}M_{\odot}\;yr^{-1}$, among the largest rates for contact systems. The periods and semi-amplitudes of the two periodic variations are about $P_3=8.7yr$ and $P_4=21.2yr$, and $K_3=0.011d$ and $K_4=0.017d$, respectively. The most reasonable explanation for both cycles is a pair of light-travel-time effects driven by the possible existence of an unseen third and fourth components with projected masses of $M_3=0.91M_{\odot}$ and $M_4=1.09M_{\odot}$ in eccentric orbits of $e_3=0.13$ and $e_4=0.73$. Because no third light was detected in the light curve synthesis, each circumbinary object could be a compact star or a binary itself.

• Journal of the Korean Society of Costume
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• v.60 no.9
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• pp.1-15
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• 2010

Fashion designer Jean Paul Gaultier incorporated his own boundless and unique artistic Into his design of dance costumes, presenting an unobstructed imaginary world that was filled with freedom, which is no less than one would expect from the one-time enfant t${\'{e}}$rrible of Paris fashion. This creativity of Gaultier was made possible only through the fantastic partnership he formed with the French modern dancer, R${\'{e}}$gine Chopinot. Gaultier and Chopinot shared a deep-rooted sympathy that enabled their own artistic worlds to fully mingle and cross over, resulting in a doubled synergy of their talent and their fame. This study analyzed 11 dancing costumes created through the collaborated efforts of those two enfants t${\'{e}}$rribles, one from the fashion industry and the other from the world of dance. The following are the results of my analysis. Gaultier's dance costumes served as a artistic venue for experimenting with a number of creative inspirations lurking in his mind, which were sometimes expressed in pr${\^{e}}$t-${\`{a}}$-porter collections. Instead of the decorative and expressive features of conventional dance costumes, his was the revival of the dancer's persona as a human being, ablaze with individuality and uniqueness. He pointed out that there is no good in the distorted turturro's fixed point of view, and the great joy of an opposing way of thinking that overturned the established. Leotard material was used as a second skin by transforming it into various styles and delivering his message. In addition, obscene and sexual expressions were delivered in a direct narrative. His eccentric ideas provided entertainment while showing his oppositional way of thinking. In the dance, the effect of the costumes was doubled by the use of cumbersome and exaggerated accessories, which is generally forbidden in modern dance.

• Structural Engineering and Mechanics
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• v.22 no.2
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• pp.169-184
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• 2006

A close form solution of the maximum deflection for cracked columns with rectangular cross-sections was developed and thus the elastic buckling behavior and ultimate bearing capacity were studied analytically. First, taking into account the effect of the crack in the potential energy of elastic systems, a trigonometric series solution for the elastic deflection equation of an arbitrary crack position was derived by use of the Rayleigh-Ritz energy method and an analytical expression of the maximum deflection was obtained. By comparison with the rotational spring model (Okamura et al. 1969) and the equivalent stiffness method (Sinha et al. 2002), the advantages of the present solution are that there are few assumed conditions and the effect of axial compression on crack closure was considered. Second, based on the above solutions, the equilibrium paths of the elastic buckling were analytically described for cracked columns subjected to both axial and eccentric compressive load. Finally, as examples, the influence of crack depth, load eccentricity and column slenderness on the elastic buckling behavior was investigated in the case of a rectangular column with a single-edge crack. The relationship of the load capacity of the column with respect to crack depth and eccentricity or slenderness was also illustrated. The analytical and numerical results from the examples show that there are three kinds of collapse mechanisms for the various states of cracking, eccentricity and slenderness. These are the bifurcation for axial compression, the limit point instability for the condition of the deeper crack and lighter eccentricity and the fracture for higher eccentricity. As a result, the conception of critical transition eccentricity $(e/h)_c$, from limit-point buckling to fracture failure, was proposed and the critical values of $(e/h)_c$ were numerically determined for various eccentricities, crack depths and slenderness.

• Smart Structures and Systems
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• v.26 no.3
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• pp.373-390
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• 2020

Hybrid simulation (HS) is a versatile tool for structural performance evaluation under dynamic loads. Although real structural responses are often multiple-directional owing to an eccentric mass/stiffness of the structure and/or excitations not along structural major axes, few HS in this field takes into account structural responses in multiple directions. Multi-directional loading is more challenging than uni-directional loading as there is a nonlinear transformation between actuator and specimen coordinate systems, increasing the difficulty of suppressing loading error. Moreover, redundant actuators may exist in multi-directional hybrid simulations of large-scale structures, which requires the loading strategy to contain ineffective loading of multiple actuators. To address these issues, lately a new strategy was conceived for accurate reproduction of desired displacements in bi-directional hybrid simulations (BHS), which is characterized in two features, i.e., iterative displacement command updating based on the Jacobian matrix considering nonlinear geometric relationships, and force-based control for compensating ineffective forces of redundant actuators. This paper performs performance validation and application of this new mixed loading strategy. In particular, virtual BHS considering linear and nonlinear specimen models, and the diversity of actuator properties were carried out. A validation test was implemented with a steel frame specimen. A real application of this strategy to BHS on a full-scale 2-story frame specimen was performed. Studies showed that this strategy exhibited excellent tracking performance for the measured displacements of the control point and remarkable compensation for ineffective forces of the redundant actuator. This strategy was demonstrated to be capable of accurately and effectively reproducing the desired displacements in large-scale BHS.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.1
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• pp.7-16
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• 1998

The Scanora/sup (R)/ X-ray unit uses the principles of narrow beam radiography and spiral tomography. Starting with a panoramic overview as a scout image. multiple tomographic projections could be selected. This study evaluated the accuracy of spiral tomography in comparison to routine panoramic radiography for dental implant treatment planning. An experimental study was performed on a cadaver mandible to assess the accuracy of panoramic radiography and spiral tomography film images for measurement of metallic spheres. After radiographic images of the metallic spheres on the surgical stent were measured and corrected for a fixed magnification of radiographic images. following results were obtained. 1. In the optimal position of the mandible. the minimal horizontal and vertical distortion was evident in the panoramic radiography images. The mean horizontal and vertical magnification error in anterior sites was 5.25％ and 0.75％. respectively. The mean horizontal and vertical magnification error in posterior sites was 0.50％ and 1.50％. respectively. 2. In the displaced forward or in an eccentric position of the mandible. the magnification error of the panoramic radiography images increased significantly over the optimal position. Overall, the mean horizontal magnification error of the anterior site in the different positions changed dramatically within a range of -17.25％ to 39.00％, compared to the posterior range of -5.25％ to 8.50％. However, the mean vertical magnification error stayed with the range of 0.5％ to 3.75％ for all the mandibular positions. 3. The magnification effects in the tomographic scans were nearly identical for the anterior and posterior with a range of 2.00％ to 5.75％ in the horizontal and 4.50％ to 5.50％ in the vertical dimension, respectively. 4. A statistically significant difference between the anterior and posterior measurements was found in the horizontal measurements of the panoramic radiography images of the displaced forward and backward position of the mandible(P<0.05). Also a significant difference between the optimal panoramic and tomographic projections was found only in the vertical measurement(P<0.05).

• Journal of Korean Dental Science
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• v.5 no.1
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• pp.29-36
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• 2012

Purpose: To investigate the effects of anterior guidance (AG) change on the working (WCP) and non-working condylar paths (NWCP), and lower incisor path (LIP) using a splint with flat (FAG) or steep AG (SAG). Materials and Methods: The samples consisted of six young adult women (mean age=$23.5{\pm}3.3$ years). Inclusion criteria were skeletal Class I and normodivergent pattern, normal overbite/overjet, minimal slide from retruded cuspal position to intercuspal position, no temporomandibular disorder signs and symptoms, mutually protected occlusion, and minimal tooth wear. After the values of natural AG (NAG) were obtained as a reference for each patient, two types of splints ($15^{\circ}$ flatter and steeper than NAG) were made. After insertion of the splints with FAG or SAG, the WCP, NWCP, and LIP were recorded five times for each patient using an ultrasonic AQR (SAM, Munich, Germany) and statistical analysis was subsequently performed. Result: NAG exhibited postero-superior movement in the WCP and did not show a noticeable immediate side shift (ISS) or difference between the eccentric (EP) and returning paths (RP) in the NWCP. FAG was associated with an irregular and excessive WCP, an increase in ISS, and a difference between EP and RP in the NWCP. SAG showed minimal WCP movement and a decrease in the extent of difference between EP and RP in the NWCP. LIP showed significant differences in EP and in RP (P<0.001, all; FAG

• Journal of the Speleological Society of Korea
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• no.79
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• pp.17-30
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• 2007

Gossi-cave, which is Natural monument No. 219, originally was called Norigok-cave, but happened Imjin-Japanese war, aborigine and Gossi family took refuse to Norigok-cave. Japanese soldiers set fire to this cave, in result lots of people had been died. And then, this cave was called Gossi-cave because Gossi family only survived during the war. Stalactite, Stone pillar that was created from four hundred million ago Harmonized with the others. The length is 6.3km in 1969.6.4. this cave was appointed natural monument as a result of investigating Korean Speleological Society. Kim SaKat a Master Poet(1807-1863) : A Genius with wit and eccentric conduct, a poet who wrote a refined poems with his own dramatic path of life destructed the format of Chines poem and created a new folk literature. He is Kim SaKat - a wizard of poet Kim Sakat - a poet wearing conical bamboo hat. Kim Sakat was born in 1807, in the latter part of Chosun period, his antonym was Kim Byung-Yun. He passed the state examination in the first place when he was 20. Two years later, he set out his life as a wanderer when he realized his winning composition was a criticism on his grandfather.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.2
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• pp.129-138
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• 2012

In this study, three types of large scale multi-tasking machine tools together with core technologies involved have been developed and introduced; a multi-tasking machine tool for large scale marine engine crankshafts, a multi-tasking vertical lathe for windmill parts, and a large scale 5-axis machine tool of gantry type. Several special purpose devices has been necessarily developed for the purpose of handling and machining big and heavy workpieces accurately, such as PTD (Pin Turning Device) with revolving ring spindle for machining eccentric crankshaft pins, hydrostatic rotary table and steady rest for supporting and resting heavy workpieces, and 2-axis automatic swiveling head for high-quality free surface machining. Core technologies have been also developed and adopted on their detail design stage; 1) structural design optimization with FEM structural analysis, 2) theoretical hydrostatic analysis for the PTD and rotary table bearings, 3) box-in-box type cross-rail and octagonal ram design to secure machine rigidity and accuracy, 4) constant spindle rpm control against gravitational torque due to unbalanced workpiece.

• Physical Therapy Korea
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• v.16 no.3
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• pp.24-31
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• 2009

This study aimed to investigate the effect of differing heel heights on the electromyographic (EMG) activity in vastus medialis (VM) and vastus lateralis (VL) during stair ascending and descending activities. A total of 26 healthy women volunteered to perform stair-ascending and stair-descending tasks with 3 heel heights: barefoot, 3 cm, and 7 cm. The EMG activities of the VM and VL were recorded during the tasks. During the stair ascending and descending tasks, the EMG activities of both VM and VL significantly changed with differing the heel heights (p<.05). Moreover, the EMG activities of VM and VL during the stair ascending task were significantly higher than the corresponding values during the stair-descending task (p<.05). However, there were no significant differences between the VM:VL EMG ratios for the 3 heel heights (p>.05). The VM:VL EMG ratios between the 2 tasks differed significantly in the 7 cm high heel condition (p<.05). Despite an increase in the EMG activities in both VM and VL during stair ascending and descending tasks, there was no change in the relative EMG intensities of VM and VL, which was measured by calculating the VM:VL ratio this result indicates that no VM:VL imbalances were elicited. The relative EMG intensities of VM and VL during stair descent were lower than the corresponding values during the ascent, suggesting that VM and VL may show an imbalance in the eccentric activation during the weight-acceptance phase. This study provides useful information that will facilitate future research on how heel height affects muscle activity around the knee joint.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.2
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• pp.58-62
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• 2002

The incidence of giant cell tumors represents only 5% to 10% of all bone tumors. Occurrence on the small bones of the hand and foot are very rare. They typically present with pain and sometimes a pathologic fracture or even soft tissue extension. The radiographic appearance is highly characteristic. An eccentric osteolytic lesion is seen, producing cortical thinning and expansion, and possessing a delicate trabecular pattern. In tarsal bones, poorly or well-defined osteolytic lesions of variable size are encountered. Surgical treatment remains the preferred therapy. Marginal or wide en bloc resection has had far better results in term of local recurrence. Several authors have suggested extended curettage and cement as an alternative to en bloc resection. Follow-up is necessary to monitor for both local recurrence and the infrequent pulmonary metastases.