• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.2
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• pp.138-142
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• 2002

Purpose: To evaluate the results and prognosis of operative repair to acute rupture of achilles tend on associated sports injury. Materials and Methods: 21 cases were surgically treated and average follow-up period was 1 year and eight months. The forth decade was most common with $55\%$ and soccer was most common in sports with 5 cases. End-to-end suture of ruptured achilles tendon was performed, and paratendinous structure was wrapped sufficiently. Postoperatively. ankle was plantarflexed for 6 weeks with longleg cast. And then 2 weeks interval, short leg cast with equinous position was conversed to functional position. About 10 weeks after operation, ankle was recovered to right angle. Hooker scale was used to evaluate the results. Results: Compared to normal side, heel-floor distance of ruptures side was decreased 0.7 cm in average, and 0.8 cm was deceased after 20 times weight loaded dorsiflexion. Mid-calf circumference was deceased 0.3 cm, and active dorsiflexion and plantar flexion of ankle was decreased each 3 and 5degree. 16 cases showed ‘excellent’result and 5 cases showed ‘satisfactory’. There was no complication, such as re-rupture or infection at operation site. Conclusion: After end-to-end operative repair to achilles tendon, sufficient wrapping of paratendinous structure is efficient for healing and prevention of postoperative adhesion. And serial dorsiflex-ion cast change is considered to be a successful treatment for preventing residual equinus deformity.

• Steel and Composite Structures
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• v.14 no.1
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• pp.73-83
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• 2013

In this paper Hamiltonian Approach (HA) have been used to analysis the nonlinear free vibration of Simply-Supported (S-S) and for the Clamped-Clamped (C-C) Euler-Bernoulli beams fixed at one end subjected to the axial loads. First we used Galerkin's method to obtain an ordinary differential equation from the governing nonlinear partial differential equation. The effect of different parameter such as variation of amplitude to the obtained on the non-linear frequency is considered. Comparison of HA with Runge-Kutta 4th leads to highly accurate solutions. It is predicted that Hamiltonian Approach can be applied easily for nonlinear problems in engineering.

• Journal of Welding and Joining
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• v.11 no.4
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• pp.112-124
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• 1993

It has been reported that fatigue damage sometimes occurred at the stress concentrated and dynamic loaded structural members of bulk carrier. In this paper, studies on fatigue strength of hull structures are reviewed, and the program for evaluating fatigue strength is developed. And the fatigue crack initiation and propagation on the end part of cargo hold frame of bulk carrier were calculated by FEM stress analysis and the fatigue strength evaluation program. These method can be applied not only to the crack initiation life but also to crack propagation life for the hull structural members at the hull design stage and be effective as the guideline to prevent the crack initiation or to estimate the fatigue strength for repairing of the fatigue damaged structures of real ships.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.359-364
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• 2004

A high-speed and intelligent CNC system has been developed by Turbotek Co., Ltd. This paper presents the study for commercialization of the developed CNC system. In order to acquire stability and reliability of the developed CNC system, its hardwares and softwares ate improved. The CNC main unit is revised to a compact box-type CNC controller. Moreover, the integrated CNC main unit that has built-in and expandable I/O modules is also developed. Remote monitoring, fault diagnosis End NURBS interpolation functions are realized on the CNC system as software modules. Through these efforts, the developed CNC system can be loaded on machine tools successfully.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.1
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• pp.16-26
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• 1998

This paper presents a design methodology for magnetically tunable X-band E-plane type waveguide filters. The proposed design is based on using of quarter wavelength transmission line for compensating the negative length transmission line of end K-inverters of E-plane type waveguide filters. The derived formulae are applied for initial design and the correction method is also provided for final design by considering the frequency dependent characteristic of K-inverters. The analysis results of E-plane pype waveguide structure loaded with ferrite slab are obtained using the edge based finite element method including higher order mode effecets. It is shown that the unilateral finline E-plane type waveguide filter as well as the bilateral finline E-plane type waveguide filter achieves the the manetically tunable characteristic. The X-band experimantal results for bilateral and unilateral finline E-plane type waveguide filters agree well with the simulated data.

• Steel and Composite Structures
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• v.23 no.3
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• pp.263-271
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• 2017

A theoretical study was carried-out of mode II delamination fracture behavior of the End Loaded Split (ELS) functionally graded beam configuration with considering the material non-linearity. The mechanical response of ELS was modeled analytically by using a power-law stress-strain relation. It was assumed that the material is functionally graded transversally to the beam. The non-linear fracture was investigated by using the J-integral approach. Equations were derived for the crack arm curvature and zero axes coordinate that are needed for the J-integral solution. The analysis developed is valid for a delamination crack located arbitrary along the beam height. The J-integral solution was verified by analyzing the strain energy release rate with considering material non-linearity. The effects of material gradient, non-linear material behavior and crack location on the fracture were evaluated. The solution derived is suitable for parametric analyses of non-linear fracture. The results obtained can be used for optimization of functionally graded beams with respect to their mode II fracture performance. Also, such simplified analytical models contribute for the understanding of delamination fracture in functionally graded beams exhibiting material non-linearity.

• Structural Engineering and Mechanics
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• v.62 no.5
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• pp.651-661
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• 2017

This paper presents an experimental study of bond-slip behavior of reinforced lightweight aggregate concrete (LC) and normal weight concrete (NC) with embedded steel bar. Tests were conducted on tension-pull specimens that had cross-sectional dimension with a reinforcing bar embedded in the center section. The experimental variables include concrete strength (20, 40, and 60 MPa) and coarse aggregate type (normal-weight aggregate and reservoir sludge lightweight aggregate). The test results show that as concrete compressive strength increased, the magnitudes of the slip of the LC specimens were greater than those of the NC specimens. Moreover, the bond strength and stiffness approaches zero at the loaded end, or close to the central anchored point of the specimen. In addition, the proposed bond stress-slip equation can effectively estimate the behavior of bond stress and steel bar slipping.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.65-68
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• 2003

In this paper, a speech recognition system using a speaker defendant algorithm is implemented on the PC. Results are loaded on a LDM display system that employs Intel StrongArm SA-1110. This research has completed so that this speech recognition system may correct its shortcomings. Sometimes a former system is operated by similar speech, not a same one. To input a vocalization is processed two times to solve mentioned defects. When references are creating, variable start-point and end-point are given to make efficient references. This references and new references are changed into feature parameter, LPC and MFCC. DTW is excuted using feature parameter. This security system will give user permission under fore execution have same result.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.751-756
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• 2000

The structural behavior of reinforced concrete slabs strengthened by glass fiber reinforced plastic-panels experimentally investigated. The experimental variables are strengthening length, strengthening width, and pre-crack existence. The pre-cracked slabs are initially loaded to 70 percent of ultimate flexural capacity and subsequently repaired with GFRP-Panels bonded to the tension face of the slabs. Five one-way slabs were tested to failure. The main failure mode of strengthened slabs is separation failure by crack propagation from load point section to end of plate. The behavior of strengthened slabs is represented by a maximum load, load-deflection curves an load-strain curves.

• Smart Structures and Systems
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• v.19 no.4
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• pp.431-439
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• 2017

This investigation is aimed to develop a model of experimental-computation determination of a support moment of a cantilever beam loaded with concentrated force at its end including the optimal choice of coordinates of deflection data points and parameters of transformation of deflection data in case of insufficient accuracy of the assignment of initial parameters (support settlement, angle of rotation of the bearing section) and cantilever beam length. The influence of distribution and characteristics of sensors on the cantilever beam on the accuracy of determining the support moment which improves in the course of transition from the uniform distribution of sensors to optimal non-uniform distribution is shown. On the basis of the theory of inverse problems the method of transformation reduction at numerical differentiation of deflection functions has been studied. For engineering evaluation formulae of uncertainty estimate to determine a support moment of a cantilever beam at predetermined uncertainty of measurements using sensors have been obtained.