• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.47-51
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• 2015

Sarcomatous Intrahepatic cholangiocarcinoma is a rare but an aggressive variant of cholangiocarcinoma with a very poor prognosis. A 79-year-old man was admitted to our hospital because of incidentally found liver mass. Magnetic resonance imaging (MRI) revealed well-defined hypointense mass on T1WI and heterogeneous hyperintense mass on T2WI. Gd-EOB-DTPA enhanced study shows peripheral rim-like enhancement in arterial phase and progressive concentric filling of contrast in delayed phase. And mass shows significant enhancement in hepatobiliary phase. The pathologic diagnosis was intrahepatic cholangiocarcinoma with sarcomatous change.

• Investigative Magnetic Resonance Imaging
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• v.22 no.3
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• pp.177-181
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• 2018

Intraperitoneal metastatic hepatocellular carcinoma (HCC) is uncommon. Although rare, it can spontaneously rupture and cause hemoperitoneum similar to primary HCC in the liver. We present a case of intraperitoneal metastatic HCC that had spontaneously ruptured and appeared as an irregularly margined hemorrhagic mass with T1 high and T2 dark signal intensities on magnetic resonance imaging. Ruptured HCC is a life-threatening emergency with high mortality rate. Spontaneously ruptured intraperitoneal metastatic HCC should be considered if a patient with a history of HCC presents with acute abdomen, although rare.

• Journal of KSNVE
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• v.9 no.6
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• pp.1200-1209
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• 1999

This paper reports a peculiar example of flow-induced vibration in a very large plant and the whole procedure of reducing the vibration. During the operation of flue gas desurfurization unit of the thermal power plant, serious vibration was dtected at all around the plant. The worst vibration was recorded on the heat exchanger surface, which weighed 180 tones, as 17.8 m/$s^2$ in vibration amplitude at 34 Hz. To identify the vibration, frequency analysis on the response vibration as well as on the expected excitation forces and the system resonance was executed. This investigation revealed that the cause of the vibration was vortex shedding from the circular pipes in the heat exchanger. Vortices from the pipes excited acoustic resonance in the heat exchanger room, which, in turn, made the structure vibrate. Through inserting the baffles between the pipes, which had an effect of cutting the acoustic wave at resonance frequency, the vibration was eliminated dramatically.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.698-699
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• 2005

Levels of fumonisins, mycotoxins produced by fungal species, must be accurately and rapidly monitored to ensure food safety. In this study, using surface plasmon resonance sensor, a batch-type biosensor was fabricated to detect fumonisin $B_1$. By applying this biosensor to fumonisin $B_1$ solutions of 0 to 6 ppm, a significant calibration model was developed for measurement. Coefficient of determination in regression analysis for the model was 0.920. Results indicate that detection of fumonisin $B_1$ by surface plasmon resonance biosensor was highly feasible.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.813-825
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• 2014

To maximize electric power production using wave energy extractions from resonance power buoys, the maximum motion displacement spectra of the buoys can primarily be obtained under a given wave condition. In this study, wave spectra observed in shoaling water were formulated. Target resonance frequencies were established from the arithmetic means of modal frequency bands and the peak frequencies. The motion characteristics of the circular cylindrical power buoys with corresponding drafts were then calculated using numerical models without considering PTO damping force. Results showed that the heave motions of the power buoys in shoaling waters with insufficient drafts produced greater amplification effects than those in deep seas with sufficient drafts.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.262-270
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• 2013

A boundary protection method for power distribution line based on equivalent boundary effect is presented in this paper. In the proposed scheme, the equivalent resonance component with a certain central frequency is sleeve-mounted at the beginning of protected zone. The 'Line Boundary' is built by using boundary effect, which is created by introducing impedance in the primary-side of line. The 'Line Boundary' is significantly different from line wave impedance. Therefore, the boundary protection principle can be applied to power distribution line without line traps. To analyze the frequency characteristic corresponding to traveling-waves of introducing impedance in the primary-side of line, distributed parameters model of equivalent resonance component is established. The results of PSCAD/EMTDC simulation prove the obvious difference of voltage high frequency component between internal faults and external faults due to equivalent resonance component, and validate the scheme.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.10
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• pp.492-498
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• 2006

A novel surface plasmon resonance(SPR) multisensing method, which does not require imaging apparatus such as CCD, has been proposed and implemented experimentally. The proposed method is based on the multichannel SPR and the separation of signals by use of additional layers whose thickness is controlled. SPR signals are influenced by the thickness of sensing layer as well as the optical condition of sensing surface. As the SPR signals from different ligands are usually positioned closely, the reflected light from sensing surface does not provide us with the clear differences of resonance signal depending on the kinds of ligands. It was found from our experiments that SPR signals from each ligand that is located on the additional layer with different thickness can be separated clearly enough to identify various signals from different ligands. Proposed method with theoretical design and simulation has been verified experimentally by using $SiO_2$ thin film layer as additional layer.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.8
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• pp.384-389
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• 2005

The Resonance Scattering Theory(RST) provides the physical explanation of the scattered field that appears in the vicinity of the resonance frequency. The theory suggests that the amplitude of each Partial-wave mode can be divided into two components : resonance and non-resonant background. The long-standing difficulty in the application of RST is that it always requires background components. We have applied the RST to the electromagnetic scattering problems by a penetrable spherical scatterer and a cavity. In this paper, we show some numerical results, and validate background coefficients.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2254-2256
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• 2000

This paper presents an implantable telemetry LC resonance-type pressure sensor for the measurement of the ventricle pressure. This sensor consists of a capacitor and an inductor. This resonant circuit is magnetically coupled with an external antenna coil. The resonance frequency of the circuit decreases as the sensor capacitance is increased by the applied pressure. The inductance and the capacitance are 428nH and 0.98${\mu}F$, respectively. The resonance frequency is 245.7MHz when the differential pressure is zero. The sensitivity of the sensor is 9.477kHz/Pa.

• Investigative Magnetic Resonance Imaging
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• v.19 no.2
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• pp.131-135
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• 2015

Vascular tumors in the breast are rare, and most can be classified as being either angiosarcomas or hemangiomas. Hemangiomas are benign vascular tumors that are usually identified incidentally. Here, we are reporting on a case of a complex hemangioma of the breast, and describing the mammography, ultrasonography, and magnetic resonance imaging findings for this patient.