• Clinical and Experimental Pediatrics
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• v.49 no.2
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• pp.187-191
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• 2006

Purpose : Malformation of cortical development(MCD) constitutes an important etiology of intractable epilepsy and is considered an indication for surgical treatments, though their efficacy is limited and variable depending on MCD's location or distribution. Ketogenic diets are widely known to be effective, but as little study has been made concerning their efficacy on epilepsy with MCD, we evaluated the efficacy of ketogenic diets on MCD patients compared with that of epileptic surgery, which is more invasive. Methods : We performed retrospective studies and analyse on 30 patients with MCD diagnosed by brain MRI and treated with ketogenic diets for intractable epilepsy since 1998, checking decreases in their seizure episodes after starting the diets. Results : Cortical dysplasia was observed in 24(80.0 percent) patients as the most common type of MCD. Also, MCD was observed in unilateral hemisphere most commonly, in 23(76.7 percent) patients; it was observed in both hemispheres in 7(23.3 percent) patients. Nine(30.0 percent) out of 30 patients became seizure-free after starting ketogenic diets, and 14(46.7 percent) patients experienced 50 percent seizure reductions as well. Age of starting the diet or the duration of epilepsy period before starting showed no statistical relationship with the efficacy of the diet. Though the younger the patient and the longer the treatment the more effective the diet seemed to be, there was no statistical correlation between them. The location of MCD showed no significance neither. Conclusion : Considering various limits and invasiveness of surgical treatment, a ketogenic diet could be a good tool in treating children with intractable epilepsy with MCD.

• Journal of the Microelectronics and Packaging Society
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• v.24 no.4
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• pp.23-29
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• 2017

The packaged optical fiber Bragg grating sensors which were networked by multiplexing the Bragg grating sensors with WDM technology were investigated in application for the structural health monitoring of the marine trestle structure transporting the ship. The optical fiber Bragg grating sensor was packaged in a cylindrical shape made of aluminum tubes. Furthermore, after the packaged optical fiber sensor was inserted in polymeric tube, the epoxy was filled inside the tube so that the sensor has resistance and durability against sea water. The packaged optical fiber sensor component was investigated under 0.2 MPa of hydraulic pressure and was found to be robust. The number and location of Bragg gratings attached at the trestle were determined where the trestle was subject to high displacement obtained by the finite element simulation. Strain of the part in the trestle being subjected to the maximum load was analyzed to be ${\sim}1000{\mu}{\varepsilon}$ and thus shift in Bragg wavelength of the sensor caused by the maximum load of the trestle was found to be ~1,200 pm. According to results of the finite element analysis, the Bragg wavelength spacings of the sensors were determined to have 3~5 nm without overlapping of grating wavelengths between sensors when the trestle was under loads and thus 50 of the grating sensors with each module consisting of 5 sensors could be networked within 150 nm optical window at 1550 nm wavelength of the Bragg wavelength interrogator. Shifts in Bragg wavelength of the 5 packaged optical fiber sensors attached at the mock trestle unit were well interrogated by the grating interrogator which used the optical fiber loop mirror, and the maximum strain rate was measured to be about $235.650{\mu}{\varepsilon}$. The modelling result of the sensor packaging and networking was in good agreements with experimental result each other.