• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.455-461
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• 2021

The causes of snapping knee include meniscal instability, but dynamic ultrasonographic findings have rarely been reported. Here, we report a case of snapping knee due to direct trauma to the right knee of a 79-year-old woman. Dynamic ultrasonography is used to confirm the snapping phenomenon caused by the anterosuperior displacement of the truncated posterior horn and body of the right medial meniscus.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.127-134
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• 2010

The dynamic instability for snapping phenomena has been studied by many researchers. Few paper deal with the dynamic bucking under the load with periodic characteristics, and the behavior under periodic excitation is expected the different behavior against STEP excitation. We investigate the fundamental mechanisms of dynamic instability when shallow EP(Elliptic Paraboliodal) shell of two degree of freedom are subjected to sinusoidal excitation with direct snapping and indirect snapping. By using Newmark-$\beta$ method, we can get the nonlinear response, and characteristics of the dynamic instability through the running response spectrum by FFT(fast Fourier Transform) and attractors are compared in the phase plane. Dynamic buckling loads are strongly influenced by the relationships between the natural frequency of structures and the dominant frequency of incident excitations.

• Journal of Korean Association for Spatial Structures
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• v.10 no.1
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• pp.119-126
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• 2010

The some papers which deal with the dynamic instability for shell-like structures under the dynamic excitation have been published, but there are few papers which treat the essential phenomenon of the dynamic buckling using the phase plane for investigating occurrence of chaos. In nonlinear dynamic, examining the characteristics of attractor on the phase plane and investigating the dynamic buckling process are very important thing for understanding why unstable phenomena are sensitively originated by various initial conditions. In this study, the direct and indirect snapping of shallow EP shell considering geometrical nonlinearity are investigated by Galerkin method numerically. This finding out the characteristic of the dynamic instability through the phases curves and running response spectrum.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.27-30
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• 2008

Snapping triceps syndrome is a rare condition in which a distal portion of triceps and ulnar nerve dislocate over the medial epicondyle as the elbow is flexed or extended from flexed position. Because it is frequently misdiagnosed as other elbow pathologies, accurate diagnosis is essential and imaging study is often needed to confirm the abnormal movement of ulnar nerve and triceps. Ultraonography is a convenient and effective method which is able to allow continual visualization of soft tissue movement compared to the other imaging modality including MRI. We reported one patient of snapping triceps syndrome who was diagnosed with the use of dynamic ultrasonography and treated with ulna nerve anterior transposition and repositioning of medial head of triceps. And we also provide the usefulness of musculoskeletal ultrasonography for the diagnosis of snapping triceps syndrome.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.4 no.1
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• pp.28-32
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• 2011

Snapping triceps syndrome is a rare disease in which medial head of triceps dislocates over the medial epicondyle during elbow flexion. It is difficult to diagnose the snapping triceps syndrome, because that this syndrome is frequently misdiagnosed as other elbow disease such as ulnarnerve dislocation. The dynamic ultrasonographic imaging allows continual visualization of the ulnar nerve and triceps muscle throughout active elbow flexion and extension. We report two patients of snapping triceps syndrome who were diagnosed with the use of dynamic ultrasonography and treated with ulnar nerve anterior transposition and repositioning or resectioning of medial head of triceps.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.185-192
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• 2002

In this study, we choose the sinusoidal shaped arch with pin-ends subjected to sinusoidal distributed excitation to investigate the fundamental mechanism of the dynamic instability. We derive the nonlinear equations of motion to investigate the instability phenomenon of arch structures and Identify the buckling characteristics of sinusoidal shaped arch structures through the nonlinear eigenvalue analysis with discreted equations of motion by Galerkin's method. We examine that phenomenons which direct snapping and indirect snapping with backbone curves to understand occurrence paths of the dynamic buckling.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.05a
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• pp.161-168
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• 2004

The dynamic instability of snapping phenomena has been studied by many researchers. Few papers deal with dynamic buckling under loads with periodic characteristics, and the behavior under periodic excitations is expected to be different from behavior under STEP excitations. We investigate the fundamental mechanisms of the dynamic instability when the sinusoidally shaped arch structures are subjected to sinusoidally distributed excitations with pin-ends. The mechanisms of dynamic indirect snapping of shallow arches are especially investigated under not only STEP function excitations but also under sinusoidal harmonic excitations, applied in the up-and-down direction. The dynamic nonlinear responses are obtained by the numerical integration of the geometrically nonlinear equation of motion, and examined by Fourier spectral analysis in order to get the frequency-dependent characteristics of the dynamic instability for various load levels.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.492-497
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• 2003

The dynamic instability for snapping phenomena has been studied by many researches. There is few paper which deal with the dynamic buckling under the load with periodic characteristics, and the behavior under periodic excitation is expected the different behavior against STEP excitation. We investigate the fundamental mechanisms of the dynamic instability when the sinusoidal shaped arch structures subjected to sinusoidal distributed excitation with pin-ends. In this study, the dynamic direct snapping of shallow arches is investigated under not only STEP load excitation but also sinusoidal harmonic excitations, applied in the up-and-down direction. The dynamic nonlinear responses are obtained by the numerical integration of the geometrically nonlinear equations of motion, and examined by the Fourier spectral analysis in order to get the frequency-dependent characteristics of the dynamic instability for various load levels.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.146-151
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• 1992

In this paper, extreme tensions in a snapping cable are studied and systematic parameter studies are made in the selected cable using the clipping-off model. The anticipation of incipient clipping frequencies of a cable are of use in giving an indication of the behavior of cables for marine applications in which large dynamic tension build-up in rough seas may cause the total tension to become negative.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.250-254
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• 2009

Purpose: Snapping triceps syndrome is dynamic condition in which medial head of triceps snaps (dislocates) over the medial epicondyle as the elbow is flexed. Materials and Methods: The symptoms are pain or snapping at the medial aspect of the elbow and/or symptoms from coexisting ulnar nerve irritation. The diagnosis can be made by dynamic ultrasonography. Results and Conclusion: And successful outcome can be archived by operative treatment, which are ulnar nerve anterior transposition and tenotomy of medial head of triceps.