Browsing by Author "Chen, Chun-Yu"

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A 1-V operated polymer vertical transistor with high on/off current ratio
(2009)
Chao, Yu-Chiang
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Tsai, Wu-Wei
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Chen, Chun-Yu
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Zan, Hsiao-Wen
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Meng, Hsin-Fei
A Wireless Human Motion Capturing System for Home Rehabilitation
(2009)
Tseng, Yu-Chee
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Wu, Chin-Hao
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Wu, Fang-Jing
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Huang, Chi-Fu
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King, Chung-Ta
Following the trend of miniature intelligent sensing, wearing small, integrated wireless sensor nodes, such as one with accelerometers and compasses, to capture human body motions may have many applications in medical care and computer animation. In this paper, we demonstrate the use of intelligent sensors to capture human motions for home rehabilitation. We design a game to help a patient to conduct his/her rehabilitation program. For each exercise, the patient is instructed to wear sensors on specified movable body parts. The system will then estimate the quality of the movements and give scores as if it is advised by a therapist. In this way, patients will no longer feel painful and boring as that in traditional rehabilitation, which is typically done in hospitals.
Cartilage Tissue-Mimetic Pellets with Multifunctional Magnetic Hyaluronic Acid-Graft-Amphiphilic Gelatin Microcapsules for Chondrogenic Stimulation
(2020-04-01)
Hou, Kai-Ting
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Liu, Ting-Yu
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Chiang, Min-Yu
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Chen, Chun-Yu
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Chang, Shwu-Jen
Articular cartilage defect is a common disorder caused by sustained mechanical stress. Owing to its nature of avascular, cartilage had less reconstruction ability so there is always a need for other repair strategies. In this study, we proposed tissue-mimetic pellets composed of chondrocytes and hyaluronic acid-graft-amphiphilic gelatin microcapsules (HA-AGMCs) to serve as biomimetic chondrocyte extracellular matrix (ECM) environments. The multifunctional HA-AGMC with specific targeting on CD44 receptors provides excellent structural stability and demonstrates high cell viability even in the center of pellets after 14 days culture. Furthermore, with superparamagnetic iron oxide nanoparticles (SPIOs) in the microcapsule shell of HA-AGMCs, it not only showed sound cell guiding ability but also induced two physical stimulations of static magnetic field(S) and magnet-derived shear stress (MF) on chondrogenic regeneration. Cartilage tissue-specific gene expressions of Col II and SOX9 were upregulated in the present of HA-AGMC in the early stage, and HA-AGMC+MF+S held the highest chondrogenic commitments throughout the study. Additionally, cartilage tissue-mimetic pellets with magnetic stimulation can stimulate chondrogenesis and sGAG synthesis.
Clinical spectrum of rhabdomyolysis presented to pediatric emergency department
(2013-09-03)
Chen, Chun-Yu
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Lin, Yan-Ren
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Zhao, Lu-Lu
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Yang, Wen-Chieh
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Chang, Yu-Jun
Background: Rhabdomyolysis is a potentially life-threatening syndrome that can develop from a variety of causes. The aim of the work is to analyze the clinical spectrum and to evaluate the prevalence of various etiologies in children, who present to the emergency department (ED) with rhabdomyolysis. Methods: During a 6-year study period, we retrospectively analyzed the medical charts of patients, aged 18 years or younger, with a definite diagnosis of rhabdomyolysis and serum creatinine phosphokinase (CK) levels greater than 1000IU/L. We analyzed the clinical spectrum and evaluated the potential risk factors of acute renal failure (ARF). Results: Thirty-seven patients (mean age = 10.2 +/- 5.5 years), including 26 males and 11 females, were enrolled in the study. Two of the most common presented symptoms in these 37 patients were muscle pain and muscle weakness (83.8% and 73%, respectively). Dark urine was reported in only 5.4% of the patients. The leading cause of rhabdomyolysis in the 0- to 9-year age group was presumed infection, and the leading cause in the 10- to 18-year age group was trauma and exercise. The incidence of ARF associated with rhabdomyolysis was 8.1 % and no child needed for renal replacement therapy (RRT). We did not identify any reliable predictors of ARF or need for RRT. Conclusions: The classic triad of symptoms of rhabdomyolysis includes myalgia, weakness and dark urine are not always presented in children. The cause of rhabdomyolysis in younger age is different from that of teenager group. However, the prognosis of rhabdomyolysis was good with appropriate management.
Competition between Fullerene Aggregation and Poly(3-hexylthiophene) Crystallization upon Annealing of Bulk Heterojunction Solar Cells
(2011-08-01)
Wu, Wei-Ru
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Jeng, U-Ser
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Su, Chun-Jen
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Wei, Kung-Hwa
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Su, Ming-Shin
Concomitant development of [6,6]-phen-C(61)-butyric acid methyl ester (PCBM) aggregation and poly(3-hexylthiophene) (P3HT) crystallization in bulk heterojunction (BHJ) thin-film (ca. 85 nm) solar cells has been revealed using simultaneous grazing incidence small-/wide-angle X-ray scattering (GISAXS/GIWAXS). With enhanced time and spatial resolutions (5 s/frame; minimum q approximate to 0.004 angstrom(-1)), synchrotron GISAXS has captured In detail the fast growth in size of PCBM aggregates from 7 to 18 nm within 100 s of annealing at 150 degrees C. Simultaneously observed is the enhanced crystallization of P3HT Into lamellae oriented mainly perpendicular but also parallel to the substrate. An Avrami analysis of the observed structural evolution indicates that the faster PCBM aggregation follows a diffusion-controlled growth process (confined by P3HT segmental motion), whereas-the slower development of crystalline P3HT nanograins is characterized by constant nucleation rate (determined by the degree. of supercooling and POW demixing). These two competing kinetics result in local phase separation with space filling PCBM and P3HT nanodomains less than 20 nm in size when annealing temperature is kept below 180 degrees C. Accompanying the morphological development is the synchronized Increase In electron and hole mobilities of the BHJ thin-film solar cells, revealing the sensitivity of the carrier transport of the device on the structural features of PCBM and P3HT nanodomains. Optimized structural parameters, including the aggregate size and mean spacing of the PCBM aggregates, are quantitatively correlated to the device performance; a comprehensive network structure of the optimized BHJ thin film is presented.
Competition between PCBM Aggregation and P3HT crystallization in thin films upon annealing
(2011-01-01)
Jeng, U-Ser
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Wu, Wei-Ru
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Su, Chun-Jen
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Wei, Kung-Hwa
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Su, Ming-Shin
Comprehensive Performance Analysis and Sleep Window Determination for IEEE 802.16 Broadband Wireless Networks
(2016-01-01)
Feng, Kai-Ten
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Su, Wun-Ci
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Chen, Chun-Yu
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電機資訊學士班
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Undergraduate Honors Program of Electrical Engineering and Computer Science
The IEEE 802.16 standard is developed to support services with high data rate and high mobility for the next generation broadband wireless access networks. There are existing sleep mode operations specified in the series of IEEE 802.16 standards in order to provide energy conservation for the mobile devices. In this paper, the analytical models for sleep mode operations of both the IEEE 802.16e and IEEE 802.16m standards are proposed, respectively. The effects of both downlink and uplink traffic are properly considered in the proposed models. Simulations are performed in order to validate the effectiveness of proposed system models. However, according to the performance evaluation for IEEE 802.16e/m system, inefficiency is observed which can be resulted from specific mechanisms within the sleep mode operations, such as frequent state transitions, under-utilized listening windows, and the adoption of binary-exponential growth of sleep window size. A POMDP-based sleep window determination (PSWD) approach is proposed in this paper, which stochastically determines the adequate length of each sleep window according to the traffic pattern. Based on the estimated traffic state, an energy cost-based sleep window determination policy is provided within the PSWD approach in consideration of tolerable network delays. Simulation results show that the proposed PSWD approach outperforms conventional IEEE 802.16e/m power-saving mechanisms in terms of energy conservation while the delay constraints are also satisfied corresponding to various traffic demands.
Concomitant tuning of metal work function and wetting property with mixed self-assembled monolayers
(2011-01-01)
Chen, Chun-Yu
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Wu, Kun-Yang
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Chao, Yu-Chiang
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Zan, Hsiao-Wen
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Meng, Hsin-Fei
The effect of the surface composition of a mixed self-assembled monolayer on the work function and wetting property of silver substrate are investigated with the mixtures of a fluorinated alkanethiol and a carboxyl-terminated alkanethiol of various chain lengths. The work function of silver can be tuned from 4.3 to 5.3 eV by changing the mixing ratio while the wetting property can be modulated by adjust the relative chain length of the fluorinated thiol and the carboxyl-terminated thiol. Thus solution-processed poly(para phenylene vinylene)-based polymer light-emitting diode was made possible with high efficiency of 6.7 cd/A and brightness of 40,000 cd/m(2). (C) 2010 Elsevier B. V. All rights reserved.
Continuous blade coating for multi-layer large-area organic light-emitting diode and solar cell
(2011-11-01)
Chen, Chun-Yu
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Chang, Hao-Wen
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Chang, Yu-Fan
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Chang, Bo-Jie
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Lin, Yuan-Sheng
A continuous roll-to-roll compatible blade-coating method for multi-layers of general organic semiconductors is developed. Dissolution of the underlying film during coating is prevented by simultaneously applying heating from the bottom and gentle hot wind from the top. The solvent is immediately expelled and reflow inhibited. This method succeeds for polymers and small molecules. Uniformity is within 10% for 5 cm by 5 cm area with a mean value of tens of nanometers for both organic light-emitting diode (OLED) and solar cell structure with little material waste. For phosphorescent OLED 25 cd/A is achieved for green, 15 cd/A for orange, and 8 cd/A for blue. For fluorescent OLED 4.3 cd/A is achieved for blue, 9 cd/A for orange, and 6.9 cd/A for white. For OLED with 2 cm by 3 cm active area, the luminance variation is within 10%. Power conversion efficiency of 4.1% is achieved for polymer solar cell, similar to spin coating using the same materials. Very-low-cost and high-throughput fabrication of efficient organic devices is realized by the continuous blade-only method. (C) 2011 American Institute of Physics. [doi:10.1063/1.3636398]
Different urinalysis appearances in children with simple and perforated appendicitis
(2013-11-01)
Chen, Chun-Yu
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Zhao, Lu-Lu
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Lin, Yan-Ren
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Wu, Kang-Hsi
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Wu, Han-Ping
Purpose: This study aimed to determine whether routine urinalysis may serve as a tool in discriminating between acute appendicitis and perforated appendicitis in children. Basic procedures: We prospectively collected 357 patients with clinically suspected acute appendicitis. Urinalysis was performed in patients with clinically suspected acute appendicitis before surgical intervention. Routine urinalysis is composed of 2 examinations: chemical tests for abnormal chemical constituents and microscopic tests for abnormal insoluble constituents. Receiver operating characteristic curves for urine white blood cell (WBC) counts and urine red blood cell (RBC) counts in distinguishing between patients with simple appendicitis and patients with perforated appendicitis were also analyzed. Main findings: Urine ketone bodies, leukocyte esterase, specific gravity, pH, WBC, and RBC counts were all significant parameters among patients with normal appendices, simple appendicitis, and perforated appendicitis (all P < .05). Based on multivariate logistic regression analysis, positive urine ketone bodies and nitrate were significant parameters in predicting perforated appendicitis (P = .002 and P = .008, respectively). According to the results of receiver operating characteristic curves, the appropriate cutoff values were 2.0/high-power field for urine RBC counts and 4.0/high-power field for urine WBC counts in predicting perforated appendicitis in children. Principal conclusions: Routine urinalysis may serve to aid in discriminating between simple and perforated appendicitis. Clinically, we believe that these urine parameters may aid primary emergency physicians with decision making in patients with clinically suspected appendicitis. (C) 2013 Elsevier Inc. All rights reserved.
Efficient multilayer red fluorescent polymer light-emitting diodes by host and guest blend system
(2010-05-01)
Syu, Wun-Shing
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Lin, Sheng-Chia
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Tseng, Shin-Rong
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Chen, Chun-Yu
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Liu, Chang-Yao
Efficient red light polymer light-emitting diodes are obtained by energy transfer from host and guest blend system. Two kinds of blend systems, SPB02:(10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1] benzopyrano [6,7,8-ij]quinolizin-11-one)(C545T):4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) and SuperYellow (SY):poly(3,3'''-didodecylquaterthiophene) (PQT-12), are used as the active layers. C545T is a green emitter, acting as an assistant dopant to improve the energy transfer from blue SPB02 host to red DCJTB. The efficiency can achieve to 3.3 cd/A for DCJTB and 3.5 cd/A for PQT-12 system by multilayer device structure with 2,2,2 ''-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBi) as electron transport layer. The SuperYellow:PQT-12 device shows great luminance of 16,930 cd/m(2). (C) 2010 Elsevier B.V. All rights reserved.
Envelope Structure of Human eNOS Protein Revealed by Small-Angle X-ray Scattering
(2012-04-01)
Chen, Chun-Yu
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Chen, Pei-Feng
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Hwu, Yeukuang
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Jeng, U-Ser
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Wu, Kun-Yu
We investigate the solution structure of human eNOS protein by using synchrotron small-angle X-ray scattering (SAXS). The pair-correlation analysis of the profile shows the radius of gyration (R-g) and maxima dimension (D-max) of 6.87 +/- 0.03 nm and 22 nm, respectively. The ratio of D-max and R-g revealed that the protein was an extended conformation. The ab initio shape determination and rigid-body calculations were performed to reconstruct the real-space structure of eNOS in solution. The result shows that human eNOS form homodimer form in solution with the closed contact of two oxygenase domains.
Epidemiology and outcome analysis of children with traumatic out-of-hospital cardiac arrest compared to nontraumatic cardiac arrest
(2013-05-01)
Chen, Chun-Yu
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Lin, Yan-Ren
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Zhao, Lu-Lu
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Wu, Yung-Kang
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Chang, Yu-Jun
This study aimed to determine predictive factors for sustained return of spontaneous circulation (ROSC) in pediatric patients with traumatic out-of-hospital cardiac arrest (OHCA) and compared to those with nontraumatic OHCA. This was a retrospective prognostic study of children with OHCA presenting to the emergency department (ED) was conducted from 2005 to 2010. Related clinical factors that influenced sustained ROSC in traumatic OHCA patients were identified and compared to nontraumatic cases. Significant parameters in predicting sustained ROSC in traumatic OHCA children were also determined using multivariate logistic regression analysis, and etiologies of the ICU admissions were analyzed in patients with sustained ROSC. Among 2,978 critically ill children admitted to the ED, 150 were pediatric OHCA patients, including 76 traumatic cases and 74 nontraumatic cases. Of children with OHCA, initial sustained ROSC was achieved in 51 cases (34.0 %), including 31 traumatic cases and 20 of nontraumatic cases. Head and neck injuries were the majority of traumatic cases in the traumatic OHCA children, followed by abdominal injuries and chest injuries. However, abdominal injuries accounted for the highest rate to gain sustained ROSC, while chest injuries had the lowest rate for successful sustained ROSC. Significant factors associated with sustained ROSC in traumatic OHCA included initial cardiac rhythm (P < 0.05), the period from scene to hospital (P < 0.05), and the duration of in-hospital cardiopulmonary resuscitation (CPR) (P < 0.05). Significant factors related to sustained ROSC have been identified as initial cardiac rhythm, duration of in-hospital CPR, and the period from scene to hospital. Head and neck injuries were the majority of traumatic cases and the prevention in head and neck trauma may play an important part in public health aspects.
High performance organic photovoltaic cells with blade-coated active layers
(2012-12-01)
Lim, Siew-Lay
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Chen, En-Chen
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Chen, Chun-Yu
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Ong, Kok-Haw
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Chen, Zhi-Kuan
High performance bulk heterojunction organic photovoltaic (OPV) cells with blade-coated active layers of POD2T-DTBT blended with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) are demonstrated in this work. The blade-coated cells exhibit power conversion efficiencies of up to 6.74%, which is comparable to those of conventional spincoated cells but obtained with just a fraction of the material amount used for spincoating. The choice of solvent and the process conditions are manipulated to achieve dense, well-separated morphology which increases the interfacial area for charge dissociation in the blend film. The blade coating technique can be applied in the fabrication of large area, high performance OPV cells with highly efficient materials usage. (C) 2012 Elsevier B.V. All rights reserved.
Higher Order Neural Networks for Well Log Data Inversion
(2008)
Huang, Kou-Yuan
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Shen, Liang-Chi
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Chen, Chun-Yu
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資訊工程學系
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Department of Computer Science
Multilayer perceptron is adopted for well log data inversion. The input of the neural network is the apparent resistivity (Ra) of the well log and the desired output is the true formation resistivity (Rt). The higher order of the input features and the original features are the network input for training. Gradient descent method is used in the back propagation learning rule. From our experimental results, we find the expanding input features can get fast convergence in training and decrease the mean absolute error between the desired output and the actual output. The multilayer perceptron network with 10 input features, the expanding input features to the third order, 8 hidden nodes, and 10 output nodes can get the smallest average mean absolute error on simulated well log data. And then the system is applied on the real well log data.
Highly efficient solution-processed red organic light-emitting diodes with long-side-chained triplet emitter
(2011-01-01)
Chao, Yu-Chiang
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Huang, Sheng-Yang
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Chen, Chun-Yu
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Chang, Yu-Fan
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Meng, Hsin-Fei
Newly synthesized red It complexes tris[2-(4-n-hexyl-phenyl)quinoline]iridium(III) and tris[(4-n-hexylphenyl)isoquinoline)]iridium(III) with long alkyl side chains are utilized to demonstrate the high efficiency multi-layer solution-processed red organic light-emitting diodes. Solubilities of these triplet emitters are high which enable them to be uniformly dispersed in the polymer host. Blade coating method is utilized to prepare organic multi-layers without mutual dissolution between different layers. 17 cd/A current efficiency, 10 lm/W power efficiency, and 8.8% external quantum efficiency can be achieved for the device with CsF/Al cathode. 10,000 cd/m(2) is reached at 10 V. Similar quantum efficiency is also achieved with an electron-transport layer and LiF/Al cathode. (C) 2010 Elsevier B.V. All rights reserved.
Identification and clinical association of anti-cytokeratin 18 autoantibody in COPD
(2010-02-16)
Kuo, Yung-Bin
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Chang, C. Allen
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Wu, Yao-Kuang
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Hsieh, Meng-Jer
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Tsai, Chung-Hsien
The etiology of chronic obstructive pulmonary disease (COPD) remains unclear. A mechanism involving the autoimmune reaction in the pathogenesis of COPD has been proposed but not confirmed. The aim of this study was to investigate whether serum autoantibodies against pulmonary cellular proteins are present in COPD patients and to identify their autoantigens if possible. Samples from 50 COPD patients and 42 control subjects were studied. Circulating autoantibodies were detected by Western blot. Immunoprecipitation and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were used to identify the autoantigens. Autoantibodies against pulmonary cellular antigens were found in the sera of COPD patients. Specifically, an autoantibody against the 45-kDa human cytokeratin 18 protein was found in 76.0% of COPD patients and 23.8% of control subjects (p < 0.001). Furthermore, the cytokeratin 18 autoantibody level was positively correlated with the FEV(1) (L) (p = 0.013) and FEV(1) (%pred.) (p, = 0.043) values observed in COPD patients. This study identified the pulmonary epithelial cytokeratin 18 protein as a COPD-associated autoantigen and found that anti-cytokeratin 18 autoantibodies were prevalent in COPD patients. Our results support the hypothesis that humoral autoimmunity may be involved in the pathogenesis of COPD. (C) 2009 Elsevier B.V. All rights reserved.
Light-emitting polymer space-charge-limited transistor
(2008-12-01)
Chen, Chun-Yu
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Chao, Yu-Chiang
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Meng, Hsin-Fei
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Horng, Sheng-Fu
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物理研究所
Polymer light-emitting transistor is realized by vertically stacking a top-emitting polymer light-emitting diode on a polymer space-charge-limited transistor. The transistor modulates the current flow of the light-emitting diode by the metal-grid base voltage. The active semiconductor of the transistor is poly(3-hexylthiophene). Yellow poly(para-phenylene vinylene) derivative is used as the yellow emitting material. As the cathode is fixed at -12 V and the grid base voltage varies from 0.9 to -0.9 V the light emission is turned on and off with on luminance up to 1208 cd/m(2). The current efficiency of the light-emitting transistor is 10 cd/A.
Low voltage active pressure sensor based on polymer space-charge-limited transistor
(2009-12-21)
Chao, Yu-Chiang
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Lai, Wei-Jen
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Chen, Chun-Yu
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Meng, Hsin-Fei
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Zan, Hsiao-Wen
Low voltage active pressure sensor is realized by vertically stacking a pressure sensitive rubber on a polymer space-charge-limited transistor. The sensor can be turned on and off by modulating the metal-grid base voltage within the range of 3 V. The output current is irrelevant to the pressure as the sensor is off. As the sensor is turned on, the output current values can be used to monitor the pressure. Reversible pressure sensing characteristics is observed below the pressure of 7.11 psi. The response time of the sensor to the pressure is as short as 22 ms. (C) 2009 American Institute of Physics. [doi:10.1063/1.3266847]
Maximum-margin sparse coding
(2017-05-17)
Liu, Chien-Liang
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Hsaio, Wen-Hoar
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Xiao, Bin
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Chen, Chun-Yu
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Wu, Wei-Liang
This work devises a maximum-margin sparse coding algorithm, jointly considering reconstruction loss and hinge loss in the model. The sparse representation along with maximum-margin constraint is analogous to kernel trick and maximum-margin properties of support vector machine (SVM), giving a base for the proposed algorithm to perform well in classification tasks. The key idea behind the proposed method is to use labeled and unlabeled data to learn discriminative representations and model parameters simultaneously, making it easier to classify data in the new space. We propose to use block coordinate descent to learn all the components of the proposed model and give detailed derivation for the update rules of the model variables. Theoretical analysis on the convergence of the proposed MMSC algorithm is provided based on Zangwill's global convergence theorem. Additionally, most previous research studies on dictionary learning suggest to use an overcomplete dictionary to improve classification performance, but it is computationally intensive when the dimension of the input data is huge. We conduct experiments on several real data sets, including Extended YaleB, AR face, and Caltech101 data sets. The experimental results indicate that the proposed algorithm outperforms other comparison algorithms without an over-complete dictionary, providing flexibility to deal with high-dimensional data sets. (C)2017 Elsevier B.V. All rights reserved.