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11.
Quen-Zong Wu I-Chang Jou Suh-Yin Lee 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》1997,27(1):148-153
An on-line signature verification scheme based on linear prediction coding (LPC) cepstrum and neural networks is proposed. Cepstral coefficients derived from linear predictor coefficients of the writing trajectories are calculated as the features of the signatures. These coefficients are used as inputs to the neural networks. A number of single-output multilayer perceptrons (MLPs), as many as the number of words in the signature, are equipped for each registered person to verify the input signature. If the summation of output values of all MLPs is larger than the verification threshold, the input signature is regarded as a genuine signature; otherwise, the input signature is a forgery. Simulations show that this scheme can detect the genuineness of the input signatures from a test database with an error rate as low as 4% 相似文献
12.
Jiin‐Jou Lih Chih‐Feng Sung Chun‐Huai Li Tiao‐Hung Hsiao Hsin‐Hung Lee 《Journal of the Society for Information Display》2004,12(4):367-371
Abstract— The characteristics of OLED backplanes including the intrinsic properties of a‐Si TFTs and LTPS TFTs will be reviewed. While LTPS TFTs reveal satisfactory stability in AMOLED‐display applications, a‐Si AMOLEDs show better uniformity and are capable of driving OLEDs. However, the stability of a‐Si TFTs under long‐term operation is still unacceptable and remains to be the key issue constraining the commercialization of a‐Si TFT AMOLEDs. 相似文献
13.
Hsun-Tsing Lee Chi-Hui Tsou Chi-Hsiung Jou Fu-Chang Huang Meng-Ling Wang Maw-Cherng Suen 《Polymer Bulletin》2014,71(11):2749-2767
In this study, 2,6-pyridinedimethanol was used as a chain extender to synthesize a new polyurethane, PDM-PU. Further, various amounts of silver nitrate were incorporated to produce PDM-PU/AgNO3 complexes. FT-IR and UV–Vis analyses confirm the formation of complex in the PDM-PU/AgNO3. DSC and DMA results show that the glass transition temperature (T g), dynamic T g and storage modulus at 25 °C of the PDM-PU/AgNO3 complexes increase with increasing AgNO3 content. This is due to the formation of complex structure that can restrict the segmental motion of polymer chains. The TGA and stress–strain test results show that the thermal decomposition temperature, tensile strength and elongation at break increase with the AgNO3 content initially. Then, they decrease inversely. This indicates that the formation of complex structure raises these properties when the AgNO3 content is below certain value. But as more coordinate bonds were formed, the specimens become brittle. In addition, the crosslink effect caused by coordinate bonds inhibits the dissolution of polymer chains and thereby reduces the swelling degree of the complexes in solvent. Furthermore, AgNO3 imparts antibacterial activity against S. aureus and K. pneumoniae to the complexes 相似文献
14.
Epidural fibrosis, an inevitable part of the postoperative healing process, is one of the important causes of failed back surgery syndrome after spinal surgery. The aim of this study was to examine the inhibitory effect of a novel material 1,4-butanediol diglycidyl ether-cross-linked hyaluronan (cHA) on fibrosis in primary tenocytes. cHA inhibited migration, cell proliferation, and suppressed the expression of fibronectin, but not transforming growth factor-β, in primary tenocytes. cHA significantly increased matrix metalloproteinase-3 but decreased collagen-1 and microtubule-associated protein light chain 3-II expression in a dose-dependent manner compared with control groups. We therefore concluded that suppressing autophagy activity may be involved in the anti-fibrotic effect of cHA in primary tenocytes. Further, cHA may have the potential for preventing epidural fibrosis and subsequent failed back syndrome in patients with laminectomy in the future. 相似文献
15.
A. Sellitto F.X. Alvarez D. Jou 《International Journal of Heat and Mass Transfer》2012,55(11-12):3114-3120
The aim of this work is to analyze the shape dependence of the effective thermal conductivity of nanowires, based on the model of phonon hydrodynamics. In particular, we consider elliptical and rectangular nanowires, and we compare their respective thermal conductivities with those of circular nanowires and of wide thin plates. 相似文献
16.
17.
A novel, polymer-based carbon nanotube (CNT) composite with high electromagnetic (EM) wave shielding effectiveness (SE) and
high mechanical properties was developed. Two types of CNTs with different aspect ratios and morphologies are compared in
this study. Amorphous carbon and graphite powder are used as reference materials. The liquid crystal polymer (LCP) and melamine
formaldehyde (MF) are used as polymer matrices to study the orientation effect of CNTs in a polymer matrix. The influences
of orientation, aspect ratio, mass fraction, and morphology of CNTs upon the shielding effectiveness (SE) of CNT/polymer composites
are investigated. The experimental results show that the higher the orientation, the aspect ratio, and the weight percentage
of nanomaterials are in the composite, the higher the polymer composites’ SE. The nanomaterials’ morphology, especially CNTs,
also affects the SE value of the polymer composite. The highest SE for the CNT/LCP composite obtained is >62 dB. The theoretically
calculated SE data are consistent with experimentally obtained data. 相似文献
18.
An optimum approach for fabrication of tapered hemispherical-end fiber for laser module packaging 总被引:2,自引:0,他引:2
H. M. Yang D. C. Jou M. H. Chen S. H. Wu W. H. Cheng 《Journal of Electronic Materials》2001,30(3):271-274
Comprehensive measurements of the dependence of coupling efficiency and radius of curvature on taper angle in a tapered hemispherical-end
fiber (THEF) for coupling between laser diodes and single-mode fibers are presented. The THEF was fabricated by etching the
fiber end in a hydrofloride (HF) solution with a thin layer of oil floating on top of the HF, and then heating in a fusion
splicer to form a hemispherical end. The results show that THEFs with larger taper angles fabricated by greater oil density
exhibit a smaller radius of curvature, and hence a better coupling efficiency. The results of this investigation have led
to an optimum approach for high-yield and high-volume fabrication of THEFs that is suitable for use in commercial laser diode
modules for efficient coupling between laser diodes and single-mode fibers. The calculation of the effect of oil density in
HF etching solution on taper angle based on a semiempirical model is in good agreement with the measured results. 相似文献
19.
Low-resistivity Mg-doped Al0.15Ga0.85N/GaN strained-layer superlattices were grown. In these superlattices, the maximum hole concentration is 3×1018/cm3 at room temperature. Hall-effect measurements indicate high conductivity of this structure in which the high activation efficiency is attributed to the strain-induced piezoelectric fields. This work also fabricated InGaN/GaN blue LEDs that consist of a Mg-doped Al0.15Ga0.85N/GaN SLs. Experimental results indicate that the LEDs can achieve a lower operation voltage of around 3 V, i.e., smaller than conventional devices which have an operation voltage of about 3.8 V 相似文献
20.
Shing Horng Lee Christina F. Jou Chien Ping Lee Cheng Chi Hu Jin Jei Wu 《Journal of Infrared, Millimeter and Terahertz Waves》1998,19(1):149-163
A frequency tunable active leaky-wave scanning antenna using Gunn-diode voltage control oscillator (VCO) as source is developed. The frequency tuning controlled by changing either the varactor diode dc bias or the Gunn diode dc bias is demonstrated. The measured scanning angle of active antenna is close to 15 degree as the Gunn VCO frequency tuned from 12.58GHz to 12.98GHz. To excite the first higher order mode of the microstrip leaky-wave antenna is fed asymmetrically. The dominant mode excitation has been successfully suppressed by adding a sequence of covered wire in the middle line of the microstrip leaky wave antenna. This is a prototype of frequency scanning antenna using two terminal device, which can be easily scaled up to millimeter wave frequency region. 相似文献