Browsing by Author "Huang, Chien-Chun"

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A Microfabricated Coil for Implantable Applications of Magnetic Spinal Cord Stimulation
(2015)
Fu, Yu-Min
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Chen, Che-Yu
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Qian, Xin-Hong
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Cheng, Yu-Ting
;
Wu, Chung-Yu
In this paper, a microfabricated inductive coil comprising of 125-turn coil windings and a MnZn-based magnetic core in a volume of 200 mm(3) is presented for the magnetic neural stimulation in a spinal cord. The coil winding with the parallel-linkage design instead of the typical serial-linkage one is proposed not only to provide better design flexibility to the current mode driving circuit but also to simplify the fabrication process of the 3-D inductive coil, which can further advance the coil miniaturization. Experimental results show the microcoil with a 1.5 A, 1 kHz square-wave current input can induce a voltages of 220 mu V on the conducting wire with an impedance of similar to 0.2 Omega @ kHz, 1 mm separation.
A novel application of the S-transform in removing powerline interference from biomedical signals
(2009-01-01)
Huang, Chien-Chun
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Liang, Sheng-Fu
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Young, Ming-Shing
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Shaw, Fu-Zen
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智慧型仿生系統研究中心
Powerline interference always disturbs recordings of biomedical signals. Numerous methods have been developed to reduce powerline interference. However, most of these techniques not only reduce the interference but also attenuate the 60 Hz power of the biomedical signals themselves. In the present study, we applied the S-transform, which provides an absolute phase of each frequency in a multi-resolution time-frequency analysis, to reduce 60 Hz interference. According to results from an electrocardiogram (ECG) to which a simulated 60 Hz noise was added, the S-transform de-noising process restored a power spectrum identical to that of the original ECG coincident with a significant reduction in the 60 Hz interference. Moreover, the S-transform de-noised the signal in an intensity-independent manner when reducing the 60 Hz interference. In both a real ECG signal from the MIT database and natural brain activity contaminated with 60 Hz interference, the S-transform also displayed superior merit to a notch filter in the aspect of reducing noise and preserving the signal. Based on these data, a novel application of the S-transform for removing powerline interference is established.
Design of a Novel Flexible Capacitive Sensing Mattress for Monitoring Sleeping Respiratory
(2014-11-01)
Chang, Wen-Ying
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Huang, Chien-Chun
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Chen, Chi-Chun
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Chang, Chih-Cheng
;
Yang, Chin-Lung
In this paper, an algorithm to extract respiration signals using a flexible projected capacitive sensing mattress (FPCSM) designed for personal health assessment is proposed. Unlike the interfaces of conventional measurement systems for poly-somnography (PSG) and other alternative contemporary systems, the proposed FPCSM uses projected capacitive sensing capability that is not worn or attached to the body. The FPCSM is composed of a multi-electrode sensor array that can not only observe gestures and motion behaviors, but also enables the FPCSM to function as a respiration monitor during sleep using the proposed approach. To improve long-term monitoring when body movement is possible, the FPCSM enables the selection of data from the sensing array, and the FPCSM methodology selects the electrodes with the optimal signals after the application of a channel reduction algorithm that counts the reversals in the capacitive sensing signals as a quality indicator. The simple algorithm is implemented in the time domain. The FPCSM system is used in experimental tests and is simultaneously compared with a commercial PSG system for verification. Multiple synchronous measurements are performed from different locations of body contact, and parallel data sets are collected. The experimental comparison yields a correlation coefficient of 0.88 between FPCSM and PSG, demonstrating the feasibility of the system design.
MULTICHANNEL PLANAR MICROELECTRODE ARRAY FOR SOMATIC MAPPING IN RATS
(2011-12-01)
Shaw, Fu-Zen
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Yang, Tsung-Fu
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Huang, Chien-Chun
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Yeh, Keng-Hung
;
Chang, Tao-Chih
Planar electrode array is an important tool to evaluate perceptual or cognitive functions of the cortex and prosthetic applications. Many construction methods have been developed. To maximize the usefulness of an array electrode, a low-cost, precise, and flexible microelectrode array with low man power and short construction duration is crucial. In this study, we introduced an 8 x 8 microelectrode array on a flexible polyimide film through microelectronics fabrication. The array dimension was capable of covering the primary somatosensory cortex of a rat. The microelectrode array was insulated with biocompatible Parylene-C except of microelectrode tip. Each electrode tip was 66 mu m height and separated with 0.5 mm to refine a detail somatic sensory processing. In pentobarbital anesthetized rats, stable spontaneous brain activity was successfully recorded through the electrode array. In addition, positive peaks of somatosensory evoked potentials (SEPs) elicited by stimulating rat's whisker pad, forepaw, hindpaw, and tail were obviously and consistently recorded. Latencies of SEPs increased as caudal part of the body was stimulated. The SEPs from stimulation of 4 body parts revealed different spatiotemporal patterns, which indicated a somatotopic organization of the rat. Our results demonstrated the superiority of the planar microelectrode array on the application of simultaneous recording and analysis of the brain activity in rats.
Through Diffusion Tensor Magnetic Resonance Imaging to Evaluate the Original Properties of Neural Pathways of Patients with Partial Seizures and Secondary Generalization by Individual Anatomic Reference Atlas
(2014)
Peng, Syu-Jyun
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Harnod, Tomor
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Tsai, Jang-Zern
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Huang, Chien-Chun
;
Ker, Ming-Dou
To investigate white matter (WM) abnormalities in neocortical epilepsy, we extract supratentorial WM parameters from raw tensor magnetic resonance images (MRI) with automated region-of-interest (ROI) registrations. Sixteen patients having neocortical seizures with secondarily generalised convulsions and 16 age-matched normal subjects were imaged with high-resolution and diffusion tensor MRIs. Automated demarcation of supratentorial fibers was accomplished with personalized fiber-labeled atlases. From the individual atlases, we observed significant elevation of mean diffusivity (MD) in fornix (cres)/stria terminalis (FX/ST) and sagittal stratum (SS) and a significant difference in fractional anisotropy (FA) among FX/ST, SS, posterior limb of the internal capsule (PLIC), and posterior thalamic radiation (PTR). For patients with early-onset epilepsy, the diffusivities of the SS and the retrolenticular part of the internal capsule were significantly elevated, and the anisotropies of the FX/ST and SS were significantly decreased. In the drug-resistant subgroup, the MDs of SS and PTR and the FAs of SS and PLIC were significantly different. Onset age was positively correlated with increases in FAs of the genu of the corpus callosum. Patients with neocortical seizures and secondary generalisation had microstructural anomalies in WM. The changes in WM are relevant to early onset, progression, and severity of epilepsy.