• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.2
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• pp.23-28
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• 1998

In this paper, the experimental and numerical results of buckling loads for laminated composite plates are compared. Using boundary conditions of buckling test are all fixed supports. Experiments were conducted for plates with fiber angles $ heta$=30$^{\circ}$, 45$^{\circ}$,60$^{\circ}$ and aspect ratio a/b=0.8. Experimental results were obtained from load-deflection curves of buckling test. Numerical methods were presented to evaluate buckling loads, using structural analysis results from ANSYS.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.408-413
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• 2004

High speed planning boats also have been required more and more the rational strength analysis and evaluation for the optimal structural design in respect of the structural lightness according to the high speed trend. Even though the suggestion of the simple type equation for the equivalent dynamic pressure is reasonable to design the scantling of ship structure conveniently, many research activities for more reasonable improvement of the simple design pressure, have been continued to suggest the more accurate equivalent static description of tire structural response such as the deflection and stress of hull structure. In this research, we focus on the aluminum bottom stiffened plate structure in which structural scantling is mainly depend on the local loads such as dynamic or impact pressure without other load effects and structural response for the simple dynamic equivalent pressure was investigated through the structural analysis. In order to investigate the structural response of the bottom stiffened plate structure subjected to the dynamic equivalent design pressure, linear and nonlinear structural analysis of the bottom stiffened plate structure of 4.3 ton aluminum planning boat was performed based on the equivalent static applied loads which were derived from the KR regulation and representative one among various dynamic equivalent pressure equations. From above analysis results, we found that the response such as deflection and stress of plate member was similar with the response results of one plate member model with fixed boundary, which was published previous paper and in case of KR design loading, all response of stiffened plate structure were within elastic limit. Through the nonlinear analysis, nearly elastic behavior including the slight geometrical nonlinear response was dominant but plastic local zone was appeared at $85\%$ limit load. Therefore, we can say that through tire linear and nonlinear analysis, this stiffened plate member has no structural strength problem based on the yield criteria in case within $60\%$ limit load except the other strength point of view such as the fatigue and buckling problem.

• The Korea Journal of Herbology
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• v.25 no.1
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• pp.75-81
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• 2010

Objectives : It was investigated new herbal prescription HT005 supported by traditional Korean medicine has a activity on the longitudinal bone growth of rats. HT005 were consisted of the root of Angelica sinensis, the fruit of Alpinia oxyphylla, the root of Astragalus membranaceus, the stem of Eleutherococcus senticosus, and the root of Dioscorea japonica, and Poria cocos. Method : To investigate the effect on longitudinal bone growth in adolescent male Sprague-Dawley rats, the longitudinal length of growth plate was measured directly by the tetracycline fluorescent labeling method and chondrocyte staining method. HT005 administered orally for four days, and the tetracycline was injected twice on the growth plate of the animals for fluorescent dying. The rate of longitudinal bone growth was measured the length between the tetracycline bands which fixed on the 3rd day and 5th day after injection. Cresyl violet was also used to stain the chondrocytes in the growth plate. The length of growth plate after administration was compared. Expression of IGF-1 and BMP-2 in the growth plate was investigated by immunohistochemistry. Results : HT005 showed a significant longitudinal bone growth which was $301.0{\pm}6.1\;{\mu}m/day$ at the dose of 100 mg/kg and $283.8{\pm}1.25\;{\mu}m/day$ (p < 0.001)at the dose of 10 mg/kg of HT005, compared to control group by the tetracycline fluorescent labeling method. HT005 showed a significant chondrocyte length on growth plate which was measured $797.19{\pm}3.31\;{\mu}m$ (p < 0.001) at the dose of 100 mg/kg and $720.14{\pm}2.19$ (p < 0.001) ${\mu}m$ at the dose of 10 mg/kg compared to the control group by cresyl-violet staining method. Both the number and intensity of BMP-2 and IGF-1 positive cells were increased in the hypertrophic zone of growth plate. There was a significant correlation between BMP-2 and IGF-1 expression and heights of chondrocytes in growth plate. Conclusions : Treatment of HT005 on Sprague-Dawley rats markedly increased the longitudinal bone growth. Therefore, HT005 may be an alternative herbal source to growth hormone as it promotes bone growth in children afflicted by growth retardation.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.149-154
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• 2006

The levator and $M{\ddot{u}}ller^{\prime}s$ muscle balanced tucking was performed to correction myogenic or aponeurotic blepharoptosis. Through the blepharoplasty incision, the upper half of tarsal plate was exposed and the orbital was opened to show the levator aponeurosis. the $M{\ddot{u}}ller^{\prime}s$ muscle dissected from the upper border of the tarsal plate and from the posteriorly located conjunctiva with sharp scissors. $M{\ddot{u}}ller^{\prime}s$ muscle was advanced about 3 mm to 8 mm on anterior surface of the tarsal plate and fixed approximately upper one third of the tarsal plate with three horizontal 6-0 Nylon mattress sutures. The amount of tucking of $M{\ddot{u}}ller^{\prime}s$ muscle was controlled by the location of the upper eyelid margin 2 mm below the upper limbus in primary gaze after first temporary fixations suture in the maximum superior point of the limbus. The amount of advancement of levator aponeurosis was controlled by the location of the upper eyelid margin 1 mm below the upper limbus in primary gaze after first temporary fixations suture in the maximum superior point of the limbus. And then levator aponeurosis was fixed with three horizontal 6-0 Nylon mattress on beside the point that was tucked $M{\ddot{u}}ller^{\prime}s$ muscle. We have been thirty cases with levator and $M{\ddot{u}}ller^{\prime}s$ muscle balanced tucking from January 2004 to Jun 2005. 3 cases were traumatic blepharoptosis with 3-5 mm ptosis and poor levator function. 27 cases were myogenic or aponeurotic blepharoptosis with 2-5 mm ptosis with and more than 4 mm of levator function. the age of the patients ranged from 6 to 78 years. The levator aponeurosis and $M{\ddot{u}}ller^{\prime}s$ muscle tucking procedure can reduce the amount of the levator and $M{\ddot{u}}ller^{\prime}s$ muscle resection, and improve discomfort when the patients open eyes.

• Journal of Advanced Marine Engineering and Technology
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• v.12 no.2
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• pp.21-34
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• 1988

Machinery enclosures are widely adopted to reduce the noise emission in various fields of application. Emitted noise, which is due to the vibration of enclosure's outer surface, is composed of two kinds of sound with different path of propagation. One is the "structure-borne sound", while the other is "air-borne sound". In order to get a most efficient machinery enclouser a prudent consideration upon the above structure-borne and air-borne sound is required, as the guiding principle of contermeasure for each noise is quite different. The controlling of input vibration and its isolation are major subjects for the structure-borne sound, and the specifications of absorbing members and damping panels are the major related matters for the air-borne sound. Hence, it seems very efficient to separate the total sounds into two categories with a great accuracy when one think of further reduction of noise from the existing enclosure, although its separating methods have not been made clear for many years. Author proposes an application method of experimental modal analysis to extract the structure-borne sound from the measured total radiation sound, as the air-borne sound is deduced by the vectorial difference between the measured total radiation sound and the calculated structure-borne sound. In order to calculate the correct structure-borne sound by the excitation at an arbitrary point on the enclosure structure, it is important to decide 1) how to estimate the enclosure's surface vibration velocity and 2) how to compute the radiation sound which is considered as the effect of vibration modes of enclosure surface. The former can be solved with total frequency response function calculated by the application of experimental modal analysis. The latter is to be solved by the author's new approaches for radiation sound computation by means of the Rayleigh's integral equation and the boundary-element method applied complex surface vibration velocity. As a first step, structure-borne sound by the excitation at an arbitry point on the rectangular plate with fixed edges, has been calculated to verified the reliability of the developed computation methods. The results of calculation show good agreements with those of the actual measurements.actual measurements.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.397-402
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• 2005

For its lowerlid entropion correction, nonsurgical eyelid suture or surgical eyelid suture can be employed. Different types of surgical eyelid suture such as the Hotz method and the Callahan method, are generally performed, but were not sufficient for correcting of entropion. In our hospital we performed modified skin-tarsal fixation on 15 patients, 5 male and 10 female from January 20, 1999 to December 16, 2002. We corrected lower eyelid entropion with the excision of the skin and orbicularis oculi muscle and buried suture of tarsal plate and dermis which is a variant of the Callahan method. All the patients were satisfied with the operation results, and there was no case of recurrence of the lower eyelid pricking the cornea. During the 6 months period after the operation, the lower eyelids slightly turned inward but there was no further progression. The correction was performed excessively, therefore there was no case of recurrence after the operation and the results were satisfactory. There developed a dimple at the suture margin caused by skin contraction but it usually disappeared within 2 months after the operation. To avoid recurrence and to achieve satisfactory results, the orbicularis oculi muscle must be totally resected at the ciliary margin. We resected ciliary as well as pretarsal portion of orbicularis oculi muscle. Also, since most of the recurrences are originated from the medial side, the medial portion of skin flap must be tightly fixed to avoid recurrence and the upper part of the dermis should be fixed tightly to the lower border of the tarsal plate.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.96-101
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• 2011

Purpose: In treatment of facial bone fracture, occurred in children, we generally use wires, miniplate, absorbable plate or their combination. These foreign bodies can be palpable, and sometimes may cause infections, and need reoperation for removing. When bone fragments are multiple, small or thin, they are hard to handle and make accurate reduction of all fragments. In these cases, a biodegradable tissue adhesive, Histoacryl$^{(R)}$ (n-butyl-2-cyanoacrylate), can be used as fixation technique for small, multiple, and thin fracture fragments. Methods: 3 years old and 6 years old children, who has comminuted fracture on frontal sinus, we used Histoacryl$^{(R)}$ for fixation of multiple bone fragments. After approaching by coronal incision, we pulled out all bone fragments and reconstructed bone fragments by Histoacryl$^{(R)}$ and fixed those on frontal sinus by absorbable plates. Results: Photographs and 3-dimensional CT obtained preoperatively and postoperatively. And we compared them each other in terms of accuracy of reconstructed bony contour. We could reconstruct almost all bone fragments easily along 3-dimensional structure and get excellent aesthetic results. There was no complication such as infection. Conclusion: In treatment of comminuted facial bone fracture, occurred in children, Histoacryl$^{(R)}$ is an excellent method for accurate reconstruction in small and thin bone fragments which cannot be fixed by wire, miniplate or absorbable plate without complication.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.2
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• pp.34-45
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• 2017

Cyclic loading tests for a total of nine test specimens were performed to evaluate the seismic performance of the exposed steel column-base plate connections. From the tests, flexural strength, deformation capacity, energy dissipation, and initial stiffness were investigated. The primary test parameters were the thickness of base-plate, embedment length of anchor bolt, the presence of hook, and rib plates. Test results showed that flexural behavior of column base-plate connection was substantially affected by the base-plate thickness, embedment length and the number of anchor bolts. On the other hand, the effect of rib plates on the increase of the flexural performance was not observed. The initial stiffness of the test specimens was about 15% of the flexural stiffness obtained by assuming that the support is fixed. As a result, even if the exposed column base-plate is designed in accordance with current design recommendations, in case that bond strength between concrete and the anchor bolts is not sufficient, the base-plate connection showed an unaccceptable load-displacement behavior.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1159_1160
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• 2009

This paper presents the numerical simulation results on the supercodnucting electrodynamic suspension (EDS) simulator according to the variation of the ground conductor. The levitation force of the EDS system is formed by the reaction between the moving magnet and the fixed ground conductor. The possible way to simulate the EDS system were simulated in this paper by using finite element method (FEM). The static type simulator which consists of the fixed magnet, the fixed ground conductor and the ac current supply system. To verify the characteristics of high speed EDS system with the moving type simulator heavy, large and fast moving ground conductor is needed. The static type simulator can get the characteristics of the high speed EDS system by applying equivalent ac current to velocity, therefore it does not need large moving part. The static type EDS simulator, which can consist of an HTS magnet, the fixed ground conductor(s), an AC power supply and the measuring devices, also test the effect of the shape of the ground conductor easily. The plate type ground conductor made stronger levitation force than ring type ground conductor. Although the outer diameter 335 mm ring type ground conductor (Ring3) was larger than the outer diameter 235 mm ground conductor (Ring2), the levitation force by Ring2 was stronger than that by Ring3. From the calculation results on this paper, the consideration of the magnetic flux distribution according to the levitation height should be included in the process of the ground conductor design.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.4
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• pp.273-279
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• 2011

Turbulent flow analysis around a wind turbine blade was performed to evaluate the power performance of offshore wind turbine. Fluent package was utilized to solve the Reynolds-averaged Navier-Stokes equations in non-inertial rotating coordinates. The realizable k-$\varepsilon$ model was used for turbulence closure and the grid system combining structured and unstructured grids was generated. In the first, lift and drag forces of 2-D foil section were calculated and compared with existing experimental data for the validation. Then torque and thrust of the wind turbine blade having NACA 4-series sections were calculated with fixed pitch angle and rpm. Tip speed ratio was varied by changing wind speed. In the next, three kinds of end plate were attached at the tip of blade in order to increase the power of the wind turbine. Among them the end plate attached at the suction side of the blade was found to be most effective. Furthermore, performance analysis with tilt angle and rake was also performed.