Browsing by Author "Chen, Yu-Han"

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A new two-DOF rotational optical image stabilizer
(2011-06-01)
Chao, Paul C-P
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Chen, Yu-Han
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Chiu, Chi-Wei
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Tsai, Meng-Yen
;
Chang, Jyh-Yeong
This work proposes design, optimization and validation of a new two degree-of-freedom (DOF) rotational optical image stabilizer (OIS) that is suitable for installing into a mobile-phone-camera. This OIS differs from the previous designs since it stabilizes the lens holder directly by two-DOF translational mechanisms that are actuated by voice coil motors. The work can be divided into three main parts: (1) designs of mechanism and genetic algorithm (GA) optimization of magnetic field, (2) establishments of the dynamic model and equation of motions (EOM) of a dual-axis rotational structure, and (3) realizations of a sliding mode control (SMC) controller with fine performance. The dynamic of the dual-axis rotational OIS system has been analyzed and the EOM has been derived. Based on the Lagrange's method, the motions of the OIS have been modeled through considering kinetic energy and electromagnetic torques. In the last part, the theory of SMC is applied, and the associated simulations are conducted. Based on the simulation results, the SMC controller is forged with the assistances from MATLAB pre-simulation and tested by a microprocessor module. After a series of experiments and verifications, the prototype of the novel OIS is finally accomplished with satisfactory performance of vibration reduction.
BIOMEDICAL SENSOR DEVICE
(2010-11-11)
Chen, Yu-Han
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Liao, Lun-De
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Chao, Paul C.-P.
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Lin, C.T.
A biomedical sensor device includes a light source, a probe array, and a photo detector. The light source is configured for emitting infrared radiation. The probe array is contacted to a user's skin to detect an electric wave signal transmitted through the probe array from the skin. The probe array includes a substrate and a plurality of probes mounted on the substrate, wherein the substrate and the probes are non-opaque so that the infrared radiation may be transmitted through the probe array into the skin. The photo detector is configured to detect an infrared signal by measuring the infrared radiation absorption by the skin.
BIOSENSOR AND ELECTRODE STRUCTURE THEREOF
(2011-03-31)
Liao, Lun-De
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Chen, Yu-Han
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Chao, Paul C.-P.
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Lin, Chin-Teng
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Sun, Arch
An electrode structure of a biosensor includes a flexible conductive substrate and a plurality of conductive probes protruding from the conductive substrate and configured for contacting a subject and receiving a physiological electric wave signal therefrom. The present invention improves disadvantages of wet electrodes and microstructure electrodes and provides more stable signals that may less decay with time so as to achieve real-time and long-acting measurement for physiological electric wave signal. A biosensor using the electrode structure is also disclosed.
Effect of Curing on the Porogen Size in the Low-k MSQ/SBS Hybrid Films
(2011)
Chen, Yu-Han
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Jeng, U-Ser
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Leu, Jihperng
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材料科學與工程學系
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Department of Materials Science and Engineering
The interaction between a polystyrene-b-polybutadiene-b-polystyrene (SBS) porogen and a low-k methylsilsesquioxane (MSQ) matrix under different curing profiles and their impact on porogen size were studied by grazing incidence small-angle X-ray scattering, viscosity measurement, and Fourier transform infrared analysis. For slow curing, significant porogen diffusion and aggregation occurred between 100 and 170 degrees C, at which the porogen size increased from 12 to 32 nm. The interaction mechanism between porogen and the MSQ matrix and its correlation with porogen size during the thermal cure process were elucidated. The aggregation of the SBS porogen was greatly influenced by the microstructure of the MSQ matrix at three controlling temperatures; namely, (1) glass transition temperature, T(g) (similar to 100 degrees C), (2) onset temperature (160 degrees C) for transforming cage to network structure, and (3) immobilization temperature (170 degrees C). In contrast, a rapid curing rate enabled the formation of small porogen size (similar to 12 nm) in the hybrid films and yielded better mechanical strength. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3529246] All rights reserved.
Effect of surfactants on the porogen size in the low-k methylsilsesquioxane/polystyrene hybrid films
(2012-11-01)
Chen, Yu-Han
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Tu, Hung-En
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Leu, Jihperng
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材料科學與工程學系
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Department of Materials Science and Engineering
An anionic surfactant, sodium dodecylbenzenesulfonate (NaDBS) and a cationic surfactant, domiphen bromide (DB) were used to modify the surface potential of polystyrene (PS) porogen in a post-integration porogen removal scheme. The effect of surfactant modification on the porogen and pore size in the low-k methylsilsesquioxane (MSQ)/PS hybrid films at 10 wt% PS loading, under a slow curing rate, was studied by grazing incidence small-angle X-ray scattering, viscosity measurement, and Fourier-transform infrared analysis. For PS porogen without modification, the porogen aggregated and its size increased from 10.0 to 16.5 nm at different rates, up to 200 degrees C, depending on the porogen diffusivity and steric hindrance by the successively cross-linked MSQ matrix at T >= T-g. In contrast, the NaDBS- and DB-modified porogens with higher surface potential impede their aggregation within the cross-linking MSQ matrix, resulting in a smaller porogen size, by electrostatic repulsion and increased viscosity due to electroviscous effect. Also, the columbic attraction between Si-OH groups of MSQ matrix and the positively charged, DB-modified PS, restrains the PS porogen, thus reduces its aggregation during cure step, leading to a small porogen size and tight distribution (8.7 +/- 2 nm) at 200 degrees C and later a similar pore size after porogen removal at 400 degrees C. (C) 2012 Elsevier Inc. All rights reserved.
Low-k SiCxNy Films Prepared by Plasma-Enhanced Chemical Vapor Deposition Using 1,3,5-trimethyl-1,3,5-trivinylcyclotrisilazane Precursor
(2012)
Tu, Hung-En
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Chen, Yu-Han
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Leu, Jihperng
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材料科學與工程學系
;
Department of Materials Science and Engineering
Low-k silicon carbonitride (SiCxNy) films with k of 3.6-4.6 were prepared by radio frequency plasma-enhanced chemical vapor deposition at 25 to 400 degrees C under low power density of 0.15 W/cm(3), using a single source precursor, 1, 3, 5-trimethyl-1,3,5-trivinylcyclotrisilazane (VSZ), and Ar. At lower deposition temperatures (<= 200 degrees C), most cyclic VSZ structures were preserved in the SiCxNy films, resulting in a lower density (1.60-1.76 g/cm(3)), a lower dielectric constant (k similar to 3.6-3.9) and a fairly good elastic modulus of 22.0-25.0 GPa. When the deposition temperature was raised to 400 degrees C, the cyclic N-Si-N linkages were reformed to a dense Si-N structure, with the desorption of CHx bonds, resulting in higher density (2.0 g/cm(3)), a dielectric constant of 4.6, and an excellent elastic modulus of 65.2 GPa. The leakage current density of SiCxNy films was reduced from 1.5x10(-6) to 4.0x10(-8) A/cm(2) at 1 MV/cm, upon increasing the deposition temperature from 25 degrees C to 400 degrees C. The conduction mechanism of the SiCxNy films, except the film deposited at 400 degrees C and tested under higher electric field, exhibited Schottky emission due to few charged defects by using a cyclic VSZ precursor and a lower plasma power density of 0.15 W/cm(3). (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.085205jes] All rights reserved.
Low-Voltage-Driven Flexible InGaZnO Thin-Film Transistor With Small Subthreshold Swing
(2010-07-01)
Su, Nai-Chao
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Wang, Shui-Jinn
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Huang, Chin-Chuan
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Chen, Yu-Han
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Huang, Hao-Yuan
A flexible thin-film transistor (TFT) was made by integrating a high-kappa HfLaO gate dielectric and an amorphous-InGaZnO (a-IGZO) active layer on a polyimide substrate. This flexible HfLaO/a-IGZO TFT exhibits a low threshold voltage of 0.1 V, a small subthreshold swing of 0.18 V/dec, a high maximum saturation mobility of 22.1 cm(2)/V . s, and an acceptable ON/OFF current ratio of 2 x 10(5). The low threshold voltage and small subthreshold swing allow the device to operate at 1.5 V for low-power applications, which should enable significant future progress in energy efficiency.
Multiple serological biomarkers for colorectal cancer detection
(2010-04-01)
Chan, Chung-Chuan
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Fan, Chung-Wei
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Kuo, Yung-Bin
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Chen, Yu-Han
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Chang, Pi-Yueh
The aim of this study was to initiate a survey of human autoantibody responses to a panel of select colorectal tumor-associated antigens identified by previous serological analysis of a cDNA expression library and to subsequently identify multiple serological biomarkers for the detection of colorectal cancer. For screening of autoantibodies against colorectal tumor-associated antigens, sera from 94 colorectal cancer patients and 54 normal controls were analyzed by enzyme-linked immunosorbent assay using recombinant rCCCAP, rHDAC5, rP53, rNMDAR and rNY-CO-16 proteins as coating antigens. Seropositivity among colorectal cancer patients to the 5 individual coating antigens varied from 18.1% to 35.1%. Seropositivity to any of the 5 coating antigens was 58.5% and combining this analysis with evaluation of serum carcinoembryonic antigen (>= 5 ng/ml) significantly increased the seropositivity to 77.6%. Seropositivity of early-stage (Dukes' Stages A and B) colorectal cancer patients to CEA was 21.9%, and seropositivity to any of the 5 colorectal cancer-associated antigens was 53.7%, and the combination of these 2 measurements resulted in a higher diagnostic capacity (65.9%) than either marker alone. In conclusion, these results collectively indicated that combined detection of serum autoantibody profiles against our panel of colorectal tumor-associated antigens and the analysis of carcinoembryonic antigen provides a promising diagnostic biomarker for colorectal cancer, particularly among early-stage patients.
Resource Allocation with CoMP Transmission in Ultra Dense Cloud-Based LTE Small Cell Networks
(2017-01-01)
Chen, Yu-Han
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Chao, Hsi-Lu
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Wu, Sau-Hsuan
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Gan, Chai-Hien
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資訊工程學系
Coordinated multipoint (CoMP) transmission has been considered an important technology to manage the serious inter-cell interference in ultra-dense small cell networks (UDN). In this paper, a scheduling framework and a two-tier spectrum resource allocation method for CoMP transmissions in UDNs are proposed. For a number of clusters, the tier-one allocation divides the resource blocks (RBs) into two sets: one is for center users and the other is for edge users. Tier-two resource allocation is performed at a central scheduler to allocate spectrum resources to edge users on a cluster basis. Applying the two-tier scheduling method to a simulated UDN on OpenStack and OpenAirInterface (OAI) software platforms, the UE throughput performances are presented and discussed. We further analyze the computational complexity of each step for performing 1-slot CoMP transmission. The numerical simulation results showed that, upon deploying the small cells in a Poisson Point Process (PPP) with mean density 0.0003/km(2), and the ratio of eNBs to UEs is (3: 1), more than 50% UEs have 15Mbps throughput performance.
Selenium nanoparticle prepared by femtosecond laser-induced plasma shock wave
(2020-01-06)
Tzeng, Wen-Yen
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Tseng, Ya-Hsin
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Yeh, Tien-Tien
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Tu, Chien-Ming
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Sankar, Raman
A novel approach for the production of both amorphous and crystalline selenium nanoparticles (SeNPs) using femtosecond laser-induced plasma shock wave on the surface of Bi2Se3 topological insulators at room temperature and ambient pressure is demonstrated. The shape and size of SeNPs can be reliably controlled via the kinetic energy obtained from laser pulses, so these are applicable as active components in nanoscale applications. Importantly, the rapid, low-cost and eco-friendly synthesis strategy developed in this study could also be extendable to other systems. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
The Role of High-kappa TiHfO Gate Dielectric in Sputtered ZnO Thin-Film Transistors
(2010)
Su, Nai-Chao
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Wang, Shui-Jinn
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Huang, Chin-Chuan
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Chen, Yu-Han
;
Huang, Hao-Yuan
In this study, we demonstrate the role of a titanium hafnium oxide (TiHfO) gate dielectric in improving the overall electronic performance of a ZnO thin-film transistor (TFT). Ti(x)Hf(1-x)O (x = 0.63) was fabricated by the rf co-sputtering technique. Using TiHfO as the gate dielectric, the device fabricated in this study exhibits a threshold voltage of 0.34 V, a subthreshold swing of 0.23 V/dec, a field-effect mobility of 2.1 cm(2) V(-1) s(-1), and an ON/OFF current ratio of 10(5). The small subthreshold swing and low positive threshold voltage are attributed to the higher value of kappa of 40 for the dielectric. This result enables device operation below 2 V, allowing its use in low-power driving circuits in display applications. (C) 2010 The Japan Society of Applied Physics