• Investigative Magnetic Resonance Imaging
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• v.21 no.3
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• pp.187-191
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• 2017

Bone marrow aspirates concentrate (BMAC) transplantation is a well-known technique for cartilage regeneration with good clinical outcomes for symptoms in patients with osteoarthritis (OA). Magnetic resonance imaging (MRI) has an important role in evaluating the degree of cartilage repair in cartilage regeneration therapy instead of a second assessment via an arthroscopy. We experienced a case of hypertrophic regeneration of the cartilage and a presumed simultaneous regeneration of the posterior horn of the lateral meniscus after BMAC transplantation for a cartilage defect at the lateral tibial and femoral condyle. This report provides the details of a case of an unusual treatment response after a BMAC transplant. This report is the first of its kind to demonstrate a MR image that displays the simultaneous regeneration of the cartilage and meniscus with a differentiation ability of the mesenchymal stem cell to the desired cell lineage.

• Steel and Composite Structures
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• v.37 no.1
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• pp.51-73
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• 2020

The present paper investigates the simultaneous resonance behavior of spiral stiffened multilayer functionally graded (SSMFG) cylindrical shells with internal and external functionally graded stiffeners under the two-term large amplitude excitations. The structure is embedded within a generalized nonlinear viscoelastic foundation which is composed of a two-parameter Winkler-Pasternak foundation augmented by a Kelvin-Voigt viscoelastic model with a nonlinear cubic stiffness. The cylindrical shell has three layers consist of ceramic, FGM, and metal. The exterior layer of the cylindrical shell is rich ceramic while the interior layer is rich metal and the functionally graded material layer is located between these layers. With regard to classical shells theory, von-Kármán equation, and Hook law, the relations of stress-strain are derived for shell and stiffeners. The spiral stiffeners of the cylindrical shell are modeled according to the smeared stiffener technique. According to the Galerkin method, the discretized motion equation is obtained. The simultaneous resonance is obtained using the multiple scales method. Finally, the influences of different material and geometrical parameters on the system resonances are investigated comprehensively.

• Journal of Korean Neurosurgical Society
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• v.58 no.4
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• pp.397-400
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• 2015

The simultaneous occurrence of an intracranial and a spinal subdural hematoma (SDH) is rare. We describe a case of cranial SDH with a simultaneous spinal SDH. An 82-year-old woman visited the emergency room because of drowsiness and not being able to walk 6 weeks after falling down. A neurological examination showed a drowsy mentality. Brain computed tomography showed bilateral chronic SDH with an acute component. The patient underwent an emergency burr-hole trephination and hematoma removal. She exhibited good recovery after the operation. On the fourth postoperative day, she complained of low-back pain radiating to both lower limbs, and subjective weakness of the lower limbs. Spine magnetic resonance imaging revealed a thoracolumbosacral SDH. A follow-up spinal magnetic resonance imaging study that was performed 16 days later showed a significant decrease in the size of the spinal SDH. We discuss the pathogenesis of this simultaneous occurrence of spinal and cranial SDH.

• ETRI Journal
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• v.31 no.2
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• pp.201-208
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• 2009

This paper proposes a spiral-shaped power island structure that can effectively suppress simultaneous switching noise (SSN) when the power plane drives high-speed integrated circuits in a small area. In addition, a new technique is presented which greatly improves the resonance peaks in a stopband by utilizing ${\lambda}$/4 open stubs on a conventional periodic electromagnetic bandgap (EBG) power plane. Both proposed structures are simulated numerically and experimentally verified using commercially available 3D electromagnetic field simulation software. The results demonstrate that they achieve better SSN suppression performance than conventional periodic EBG structures.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.4
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• pp.9-14
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• 1999

In this paper, we proposed a simultaneous switching noise (SSN) reduction technique in multi-layer boards (MLB) for high-speed digital applications and analyzed it using the Finite Difference Time Domain (FDTD) method. The new structure using conductive dielectric substrates is effective for the reduction of SSN couplings and resonances. The uniform insertion of the conducive layer reduced the SSN coupling and resonance by 85% and the partial insertion only around the edges reduced by 55% respectively.

• Investigative Magnetic Resonance Imaging
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• v.16 no.2
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• pp.169-172
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• 2012

Simultaneous bilateral spontaneous rupture of the quadriceps tendon is a very rare condition and only a few cases have been reported in the literature. The etiology is not clear yet. But it occurs infrequently in patients with chronic metabolic disorders, such as secondary hyperparathyroidism due to chronic renal failure. We describe a case of simultaneous spontaneous bilateral quadriceps tendon tupture in a 36-year-old male patient with secondary hyperaprathyroidism due to chronic renal failure.

• Proceedings of the KSMRM Conference
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• 2006.11a
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• pp.32-32
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• 2006

• ETRI Journal
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• v.23 no.3
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• pp.106-110
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• 2001

Subpicosecond all-optical switching method based on the simultaneous two-photon coherence exchange is proposed and numerically demonstrated. The optical switching mechanism is based on the optical field induced dark resonance swapping via nondegenerate four-wave mixing processes. For potential applications of ultrafast all-optical switching in fiber-optic communications, 10-THz channel number independent quantum router is discussed.

• Journal of the Korean Arthroscopy Society
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• v.10 no.1
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• pp.95-98
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• 2006

Most of discoid menisci are lateral and medial discoid meniscus is very rare. There is no report about simultaneous medial and lateral discoid meniscus in one knee joint. A 15-year-old male patient was diagnosed as having a complete medial discoid meniscus with horizontal tear and intact incomplete lateral discoid meniscus by means of magnetic resonance image and arthroscopy. The patient was treated by arthroscopic partial meniscectomy for both discoid menisci.

• Investigative Magnetic Resonance Imaging
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• v.21 no.4
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• pp.210-222
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• 2017

Purpose: To develop a novel combination of controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA) with integrated SSFP (CAIPI-iSSFP) for accelerated SSFP imaging without banding artifacts at 3T. Materials and Methods: CAIPI-iSSFP was developed by adding a dephasing gradient to the balanced SSFP (bSSFP) pulse sequence with a gradient area that results in $2{\pi}$ dephasing across a single pixel. Extended phase graph (EPG) simulations were performed to show the signal behaviors of iSSFP, bSSFP, and RF-spoiled gradient echo (SPGR) sequences. In vivo experiments were performed for brain and abdominal imaging at 3T with simultaneous multi-slice (SMS) acceleration factors of 2, 3 and 4 with CAIPI-iSSFP and CAIPI-bSSFP. The image quality was evaluated by measuring the relative contrast-to-noise ratio (CNR) and by qualitatively assessing banding artifact removal in the brain. Results: Banding artifacts were removed using CAIPI-iSSFP compared to CAIPI-bSSFP up to an SMS factor of 4 and 3 on brain and liver imaging, respectively. The relative CNRs between gray and white matter were on average 18% lower in CAIPI-iSSFP compared to that of CAIPI-bSSFP. Conclusion: This study demonstrated that CAIPI-iSSFP provides up to a factor of four acceleration, while minimizing the banding artifacts with up to a 20% decrease in the relative CNR.