Browsing by Issue Date, starting with "2012-11-08"

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Ultra-low voltage implicit multiplexed differential flip-flop with enhanced noise immunity
(2012-11-08)
Sung, W. -H.
;
Lee, M. -C.
;
Chung, C. -C.
;
Lee, C. -Y.
;
電子工程學系及電子研究所
An ultra-low voltage 22T implicit multiplexed differential (IMD) flip-flop (FF) is proposed. An implicit multiplexer is designed to simplify the differential FF complexity, while its control data path is able to enhance the FF noise immunity as well. So, the fully static IMD-FF with modified differential topology provides a sufficient noise margin under voltage scaling. On the other hand, the IMD-FF operation avoids considerable DC current dissipation to save active power and suppresses the idle leakage by stacked transistors. The post-layout simulation in 90 nm CMOS process with 400 mV supply voltage shows that the IMD-FF achieves 56% active power and 42.2% leakage power reduction. The tolerable noise energy is enhanced by 18.9% on average. Finally, this work provides 93% function yield rate under the effect of process-voltage-temperature variations and 40 pJ input noise energy.
Regional surface mass anomalies from GRACE KBR measurements: Application of L-curve regularization and a priori hydrological knowledge
(2012-11-08)
Tangdamrongsub, Natthachet
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Hwang, Cheinway
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Shum, C. K.
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Wang, Lei
;
土木工程學系
We present a method of directly estimating surface mass anomalies at regional scales using satellite-to-satellite K-band Ranging (KBR) data from the Gravity Recovery and Climate Experiment (GRACE) twin-satellite mission. Geopotential differences based primarily on KBR measurement are derived using a modified energy integral method with an improved method to calibrate accelerometer measurements. Surface mass anomalies are computed based on a downward continuation process, with optimal regularization parameters estimated using the L-curve criterion method. We derive the covariance functions in both space-and space-time domains and use them as light constraints in the regional gravity estimation process in the Amazon basin study region. The space-time covariance function has a time-correlation distance of 1.27 months, which is evident that observations between neighboring months are correlated and the correlation should be taken into account. However, most of the current GRACE solutions did not consider such temporal correlations. In our study, the artifact in the regional gravity solution is mitigated by using the covariance functions. The averaged commission errors are estimated to be only 6.86% and 5.85% for the solutions based on the space-covariance function (SCF) and the space-time covariance function (STCF), respectively. Our regional gravity solution in the Amazon basin study region, which requires no further post-processing, shows enhanced regional gravity signatures, reduced gravity artifacts, and the gravity solution agrees with NASA/GSFC's GRACE MASCON solution to about 1 cm RMS in terms of water thickness change over the Amazon basin study region. The regional gravity solution also retains the maximum signal energy while suppressing the short wavelength errors.
METHOD FOR DYNAMICALLY SETTING ENVIRONMENTAL BOUNDARY IN IMAGE AND METHOD FOR INSTANTLY DETERMINING HUMAN ACTIVITY
(2012-11-08)
Song Kai-Tai
;
Chen Wei-Jyun
The present invention provides a method for dynamically setting an environmental boundary in an image and a method for instantly determining human activity according to the method for dynamically setting the environmental boundary. The method for instantly determining human activity includes the steps of retrieving at least an initial environmental image with a predetermined angle, and calculating a boundary setting equation of an object and an environmental boundary in the initial environmental image; retrieving a dynamic environmental image having the object by using a movable platform, and figuring out a new environmental boundary; determining a human image in the dynamic environmental image, recording retention time of the human image, and determining a human posture; and determining human location according to the environmental boundary in the dynamic environmental image and the human image, and instantly determining the human activity.
Mechanism and Kinetics for Ammonium Dinitramide (ADN) Sublimation: A First-Principles Study
(2012-11-08)
Zhu, R. S.
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Chen, Hui-Lung
;
Lin, M. C.
;
應用化學系分子科學碩博班
;
Institute of Molecular science
The mechanism for sublimation of NH4N(NO2)(2) (ADN) has been investigated quantum-mechanically with generalized gradient approximation plane-wave density functional theory calculations; the solid surface is represented by a slab model and the periodic boundary conditions are applied. The calculated lattice constants for the bulk ADN, which were found to consist of NH4+[ON(O)NNO2](-) units, instead of NH4+[N(NO2)(2)](-), agree quite well with experimental values. Results show that three steps are involved in the sublimation/decomposition of ADN. The first step is the relaxation of the surface layer with 1.6 kcal/mol energy per NH4ON(O)NNO2 unit; the second step is the sublimation of the surface layer to form a molecular [NH3]-[HON(O)NNO2] complex with a 29.4 kcal/mol sublimation energy, consistent with the experimental observation of Korobeinichev et al.(10) The last step is the dissociation of the [H3N]-[HON(O)NNO2] complex to give NH3 and HON(O)NNO2 with the dissociation energy of 13.9 kcal/mol. Direct formation of NO2 (g) from solid ADN costs a much higher energy, 58.3 kcal/mol. Our calculated total sublimation enthalpy for ADN(s) -> NH3(g) + HON(O)NNO2) (g), 44.9 kcal/mol via three steps, is in good agreement with the value, 42.1 kcal/mol predicted for the one-step sublimation process in this work and the value 44.0 kcal/mol computed by Politzer et al.(11) using experimental thermochemical data. The sublimation rate constant for the rate-controlling step 2 can be represented as k(sub) = 2.18 x 10(12) exp (-30.5 kcal/mol/RT) s(-1), which agrees well with available experimental data within the temperature range studied. The high pressure limit decomposition rate constant for the molecular complex H3N center dot center dot center dot HON(O)NNO2 can be expressed by k(dec) = 3.18 x 10(13) exp (-15.09 kcal/mol/RT) s(-1). In addition, water molecules were found to increase the sublimation enthalpy of ADN, contrary to that found in the ammonium perchlorate system, in which water molecules were shown to reduce pronouncedly the enthalpy of sublimation.
LMI-based robust sliding control for mismatched uncertain nonlinear systems using fuzzy models
(2012-11-10)
Liu, Sung-Chieh
;
Lin, Sheng-Fuu
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電機工程學系
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Department of Electrical and Computer Engineering
We propose a robust sliding control design method for uncertain TakagiSugeno fuzzy models. The uncertain fuzzy systems under consideration have mismatched parameter uncertainties in the state matrix and external disturbances. We make the first attempt to relax the restrictive assumption that each nominal local system model shares the same input channel, which is required in the traditional VSS-based fuzzy control design methods. We derive the existence conditions of linear sliding surfaces guaranteeing the asymptotic stability in terms of constrained LMIs. We present an LMI characterization of such sliding surfaces. Also, an LMI-based algorithm is given to design the switching feedback control term so that a stable sliding motion is induced in finite time. Finally, we give two simulation results to show the effectiveness of the proposed method. Copyright (c) 2011 John Wiley & Sons, Ltd.
全數位快速鎖定自我校正多相位延遲鎖定迴路
(2012-11-11)
莊立溥
;
張銘宏
;
黃威
本發明揭露了一種全數位自我校正多相位延遲鎖定迴路，其包含四個主要的區塊，分別為：一組數位式控制延遲線，一相位偵測器，一鎖定單元，及一自我校正單元。數位式控制延遲線係由K個相同之延遲級(delay stage)串連所形成，而所有的延遲級皆係由兩組控制訊號C[M：0]與Bi[N：0]所控制。C[M：0]係由採用非平衡式二元搜尋演算法之鎖定單元所產生。當延遲鎖定迴路鎖定時，自我校正單元將產生Bi[N：0]訊號以調整各級輸出訊號之間的相位差。
Reply to Comment on "Chemical-Composition-Dependent Metastability of Tetragonal ZrO2 in Sol-Gel-Derived Films under Different Calcination Conditions"
(2012-11-13)
Chang, Sue-min
;
Doong, Ruey-an
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環境工程研究所
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Institute of Environmental Engineering
Adjustable implant electrode system and implant electrode assembly thereof
(2012-11-13)
Choi Charles Tak-Ming
;
Hsu Chien-Hua
An adjustable implant electrode system comprises an adjustable implant electrode assembly and an adjustment device for adjusting the adjustable implant electrode assembly to a desired position. The adjustable implant electrode assembly comprises an implant, a plurality of electrodes, and a plurality of magnetic components. The electrodes are disposed in the implant for providing stimulating currents according to a control signal. The magnetic components are combined with the electrodes in one-to-one correspondence. The adjustment device comprises a control unit, an excitation unit, and one or more magnetic units. The control unit is used to select one or more magnetic components to be moved from the magnetic components, and the excitation unit is used to excite the selected one or more magnetic components for the same to generate a magnetic pole, and the magnetic unit is adapted to generate a magnetic field to drive the magnetic pole and accordingly move the implant.
Piezoelectric panel speaker and optimal method of designing the same
(2012-11-13)
Bai Mingsian R.
;
Tsai Yao-Kun
A piezoelectric panel speaker and an optimal method of designing the same is disclosed. In the structure of the speaker, at least one piezoelectric plate attached at a surrounding frame supports a diaphragm inside the surrounding frame. A spacer is inserted between the piezoelectric plate and the diaphragm. The structure of the piezoelectric plates fixed at the surrounding frame improves the speaker performance within the low frequency range. The finite element method is employed to build a mathematical model to simulate the sound pressure loading of the piezoelectric panel speaker. Also, the simulated annealing method is employed to approach the optimal design parameters of the speaker structure.
Dynamic overlay multicast for live multimedia streaming in urban VANETs
(2012-11-14)
Hsieh, Yi-Ling
;
Wang, Kuochen
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應用化學系
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資訊工程學系
;
Department of Applied Chemistry
Infotainment service has been a foreseeing trend in VANETs (Vehicular Ad Hoc Networks), and multimedia streaming has a high potential in VANET infotainment service. This paper considers the scenario of live multimedia streaming multicast to vehicles of the same group using a dynamic application layer overlay. Due to the willingness for cooperation of non-group nodes, application layer overlay multicast is more feasible than other kinds of multicast such as network-coding-based multicast and network-layer multicast. To adapt to high mobility and full of obstacles in urban VANETs, we propose an effective dynamic overlay multicast scheme for multimedia streaming, called OMV (Overlay Multicast in VANETs). The proposed OMV enhances an overlay's stability with two strategies: (1) QoS-satisfied dynamic overlay and (2) mesh-structure overlay. The QoS-satisfied strategy to adjust the overlay selects potential new parents based on their streams' packet loss rates and end-to-end delays. The mesh-structure strategy allow; a child to have multiple parents. We evaluate the proposed OMV in urban VANETs with obstacles using two real video clips to demonstrate the feasibility of the OMV for real videos. Evaluation results show that comparing the proposed OMV to Qadri et al.'s work, which is a static mesh overlay and is the best method available in VANETs, the packet loss rate is reduced by 27.1% and the end-to-end delay is decreased by 11.7%, with a small control overhead of 2.1%, on average. Comparing the proposed OMV for tree overlays to ALMA, which is for dynamic tree multicast overlays and is also the best method available in MANETs, the packet loss rate is reduced by 7.1% and the end-to-end delay is decreased by 13.1%. In addition, to address the problem of obstacle-prone urban VANETs, we also derive feasible stream rates and overlay sizes for city maps with different road section sizes. To the best of our knowledge, how to organize and dynamically adjust an application layer multicast overlay for live multimedia streaming have not been studied in existing VANET literatures. In summary, to deal with highly dynamic topologies in urban VANETs. we propose a QoS-satisfied strategy for group nodes to switch to new parents that can offer better QoS. The proposed OMV is feasible for live multimedia streaming applications, such as emergency live video transmission and live video tour guides for passengers in different vehicles that belong to the same multicast group. (c) 2012 Elsevier B.V. All rights reserved.
Decision tree-based learning to predict patient controlled analgesia consumption and readjustment
(2012-11-14)
Hu, Yuh-Jyh
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Ku, Tien-Hsiung
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Jan, Rong-Hong
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Wang, Kuochen
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Tseng, Yu-Chee
Background: Appropriate postoperative pain management contributes to earlier mobilization, shorter hospitalization, and reduced cost. The under treatment of pain may impede short-term recovery and have a detrimental long-term effect on health. This study focuses on Patient Controlled Analgesia (PCA), which is a delivery system for pain medication. This study proposes and demonstrates how to use machine learning and data mining techniques to predict analgesic requirements and PCA readjustment. Methods: The sample in this study included 1099 patients. Every patient was described by 280 attributes, including the class attribute. In addition to commonly studied demographic and physiological factors, this study emphasizes attributes related to PCA. We used decision tree-based learning algorithms to predict analgesic consumption and PCA control readjustment based on the first few hours of PCA medications. We also developed a nearest neighbor-based data cleaning method to alleviate the class-imbalance problem in PCA setting readjustment prediction. Results: The prediction accuracies of total analgesic consumption (continuous dose and PCA dose) and PCA analgesic requirement (PCA dose only) by an ensemble of decision trees were 80.9% and 73.1%, respectively. Decision tree-based learning outperformed Artificial Neural Network, Support Vector Machine, Random Forest, Rotation Forest, and Naive Bayesian classifiers in analgesic consumption prediction. The proposed data cleaning method improved the performance of every learning method in this study of PCA setting readjustment prediction. Comparative analysis identified the informative attributes from the data mining models and compared them with the correlates of analgesic requirement reported in previous works. Conclusion: This study presents a real-world application of data mining to anesthesiology. Unlike previous research, this study considers a wider variety of predictive factors, including PCA demands over time. We analyzed PCA patient data and conducted several experiments to evaluate the potential of applying machine-learning algorithms to assist anesthesiologists in PCA administration. Results demonstrate the feasibility of the proposed ensemble approach to postoperative pain management.
CHINESE SPEECH RECOGNITION SYSTEM AND METHOD
(2012-11-15)
YANG Jyh-Her
;
Chiang Chen-Yu
;
Liu Ming-Chieh
;
Wang Yih-Ru
;
Liao Yuan-Fu
A Chinese speech recognition system and method is disclosed. Firstly, a speech signal is received and recognized to output a word lattice. Next, the word lattice is received, and word arcs of the word lattice are rescored and reranked with a prosodic break model, a prosodic state model, a syllable prosodic-acoustic model, a syllable-juncture prosodic-acoustic model and a factored language model, so as to output a language tag, a prosodic tag and a phonetic segmentation tag, which correspond to the speech signal. The present invention performs rescoring in a two-stage way to promote the recognition rate of basic speech information and labels the language tag, prosodic tag and phonetic segmentation tag to provide the prosodic structure and language information for the rear-stage voice conversion and voice synthesis.
Effect of processing kinetics on the structure of ferromagnetic-ferroelectric-ferromagnetic interfaces
(2012-11-15)
Krishnan, P. S. Sankara Rama
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Ramasse, Q. M.
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Liang, Wen-I
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Chu, Ying-Hao
;
Nagarajan, V.
Trilayer heterostructures consisting of a ferroelectric bismuth ferrite (BFO) film sandwiched between ferromagnetic lanthanum strontium manganese oxide (LSMO) films were fabricated using pulsed laser deposition. Both BFO thicknesses (20 nm, 5 nm) and cooling rates were varied to investigate the role of processing parameters on the chemistry of the interfaces. The interfaces were investigated using a dedicated aberration corrected scanning transmission electron microscope (STEM) operated at 100 kV via STEM-high angle annular dark field (STEM-HAADF) and STEM-electron energy loss spectroscopy (STEM-EELS) modes. Combined analysis through STEM-HAADF and STEM-EELS revealed the formation of lattice distortion in certain regions of the BFO layer for the similar to 5 nm film. Piezoresponse force microscopy (PFM) studies of the similar to 5 nm BFO sample revealed weak ferroelectric domain switching. Stacking fault defects with mixed valence manganese (Mn-B site cation) were formed in the top LSMO layer when the heterostructure was cooled at a slower rate irrespective of BFO thickness, thereby demonstrating the effect of processing kinetics on the physical integrity of the heterostructure. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4765045]
PHOTO-CROSSLINKABLE LIQUID CRYSTAL MONOMERS WITH OPTICAL ACTIVITY
(2012-11-15)
CHEN Yu-hsien
;
LIU Sheng-fa
;
LI Huai-an
;
FUH Sin-min
;
LIN Hong-cheu
The present invention relates to photo-crosslinkable liquid crystal monomers with optical activity. The liquid crystal monomers contains one chiral center with an acrylate group or terminal diacrylate groups, and terminal dibenzene rings are introduced in order to extend its hard segment for the purpose of getting a wider liquid crystalline phase. By introducing the liquid crystal monomers, the room temperature nematic liquid crystal or the cholesteric liquid crystal may have a better mutual solubility and a wider, steadier structure of liquid crystal. The liquid crystal monomers have the following formula structure:
Phase evolution of magnetite nanocrystals on oxide supports via template-free bismuth ferrite precursor approach
(2012-11-15)
Cheung, Jeffrey
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Bogle, Kashinath
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Cheng, Xuan
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Sullaphen, Jivika
;
Kuo, Chang-Yang
This report investigates the phase evolution pathway of magnetite nanocrystal synthesis on oxide-supported substrates. A template-free phase separation approach, which exploits the thermodynamic instability of ternary perovskite BiFeO3 and inherent volatility of bismuth oxide in low oxygen pressure and high temperature is presented. The formation of an intermediate hematite nanocrystal phase is found as a key step that controls the eventual size and morphology of the magnetite nanocrystals. X-ray absorption spectra measurements and X-ray magnetic circular dichroism confirm that the spectral fingerprints of the magnetite nanocrystals match with that of bulk crystals. Magnetic measurements show that magnetic anisotropy is directly attributed to the nanocrystal morphology. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4766748]
LOAD-ADAPTIVE BIOELECTRIC CURRENT STIMULATOR
(2012-11-15)
Ker Ming-Dou
;
Chen Wei-Ling
;
Lin Chun-Yu
The disclosure relates to a load-adaptive bioelectrical current stimulator, which comprises a current output module, an adaptation module and a control module. The current output module generates a stimulus current to an electrode. The adaptation module detects the electrical status of the stimulus current passing through the electrode and generates a feedback signal to the control module. According to the feedback signal, the control module controls the current output module to stabilize the output status of the stimulus current adaptively. Thereby, the load-adaptive bioelectrical current stimulator can use the feedback control mechanism to regulate the value of the stimulus current to adapt to variation of load impedance.
Active touch sensing circuit apparatus
(2012-11-15)
Tai Ya-Hsiang
;
Chou Lu-Sheng
;
Chiu Hao-Lin
The invention discloses an active matrix touch sensing circuit apparatus used in a touch panel comprises a sensing unit, a resistance, and a thin film transistor. The resistance connects the sensing unit and the first scan line. The control end of the thin film transistor connects the sensing unit, the second scan line connects the input end of the thin film transistor, and the read out line connects the output end of the thin film transistor. When the sensing value of the body touch sensing unit is changed, and then the input wave form of the control end is changed. The output end generates an open current, and the read out line transmits the open current.
Exploring the spatio-temporal dynamics of an optically pumped semiconductor laser with intracavity second harmonic generation
(2012-11-15)
Liang, Hsing-Chih
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Lee, Yi-Chun
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Tung, Jung-Chen
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Su, Kuan-Wei
;
Huang, Kai-Feng
We experimentally observe an intriguing phenomenon of complex spatio-temporal dynamics in a commercial optically pumped semiconductor laser with intracavity second harmonic generation. We numerically verify that the experimental results come from the total mode locking of transverse electromagnetic modes (TEM00) and higher-order modes with significant astigmatism. The scenarios of the spatio-temporal dynamics are quite similar to the phenomena in soft-aperture Kerr-lens mode locked Ti:sapphire lasers. (C) 2012 Optical Society of America
Rotational Invariance of the Effective Refractive Index in Photonic Crystals
(2012-11-15)
Pei, Ting-Hang
;
Huang, Yang-Tung
;
材料科學與工程學系
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電子工程學系及電子研究所
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Department of Materials Science and Engineering
The rotational invariance of the effective refractive index in the 2-D photonic crystal is discussed. It is proven that, in the case of the n-fold symmetrical omega-k equifrequency surface (EFS), there are two solutions that show the invariance of the effective refractive index after rotating a multiple of the basic repeated angle 2 pi/n within the first Brillouin zone. For the noncircular solution, the behavior of the effective refractive index N-eff(theta) at normal incidence shows that N-eff(0 degrees) has an additional constant of two in the very high symmetric EFS, higher than in the low symmetric case.
中文語音辨識裝置及其辨識方法
(2012-11-16)
楊智合
;
江振宇
;
劉銘傑
;
王逸如
;
廖元甫
本發明係揭露一種中文語音辨識裝置及其辨識方法，首先，接收一語音訊號，以進行辨識後，輸出一格狀詞組(word lattice)。接著，接收格狀詞組，並根據一韻律停頓模型、一韻律狀態模型、一音節韻律聲學模型、一音節間韻律聲學模型與一因子化語言模型，重新計算格狀詞組中詞弧上的分數，將其重新排名，以輸出語音訊號對應之一語言標籤、一韻律標籤與一音段標記。本發明利用兩階段方式重新計分，不僅可提升基本語音資訊的辨識率，更可標記出語言、韻律、音段等標籤，以供後級語音技術所需的韻律結構與語言資訊。