Browsing by Author "Huang, CF"

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0.1 mu m poly-Si thin film transistors for system-on-panel (SoP) applications
(2005)
Tsui, BY
;
Lin, CP
;
Huang, CF
;
Xiao, YH
;
電子工程學系及電子研究所
Thin active layer, fully-silicided source/drain (S/D), modified Schottky barrier, high dielectric constant (high-k) gate dielectric, and metal gate technologies are integrated to realize high performance TFTs. Devices with 0.1 mu m channel length were fabricated successfully. Low threshold voltage, low subthreshold swing, high effective mobility, low S/D resistance, high on/off current ratio, and good control of threshold voltage are demonstrated.
A constrained multibody system dynamics avoiding kinematic singularities
(2002-03-01)
Huang, CF
;
Yan, CD
;
Jeng, SL
;
Cheing, WH
;
機械工程學系
In the analysis of constrained multibody systems, the constraint reaction forces are normally expressed in terms of the constraint equations and a vector of Lagrange multipliers. Because it fails to incorporate conservation of momentum, the Lagrange multiplier method is deficient when the constraint Jacobian matrix is singular. This paper presents an improved dynamic formulation for the constrained multibody system. In our formulation, the kinematic constraints are still formulated in terms of the joint constraint reaction forces and moments; however, the formulations are based on a second-order Taylor expansion so as to incorporate the rigid body velocities. Conservation of momentum is included explicitly in this method; hence the problems caused by kinematic singularities can be avoided. In addition, the dynamic formulation is general and applicable to most dynamic analyses. Finally the 3-leg Stewart platform is used for the example of analysis.
A new strategy for the one-step synthesis of block copolymers through simultaneous free radical and ring opening polymerizations using a dual-functional initiator
(2005-02-14)
Huang, CF
;
Kuo, SW
;
Lee, HF
;
Chang, FC
;
應用化學系
Block copolymers are fascinating and complex materials that have been used in a range of diverse scientific and technological capacities. We demonstrate that a single one-step approach based on dual simultaneous polymerizations is a viable technique for the synthesis of a wide range of block copolymers by combining two dissimilar polymerization systems and using a dual-functional initiator. The main advantage of this methodology is that a simple, one-step, and simultaneous polymerization occurs in the bulk, which makes this process very attractive from both industrial and academic points of view. We plan to study the reaction kinetics and evaluate how well the ring opening catalyst [in this case, Sn(oct)(2)] works under reverse ATRP conditions. (C) 2004 Elsevier Ltd. All rights reserved.
A novel washout filter design for a six degree-of-freedom motion simulator
(2004-06-01)
Liao, CS
;
Huang, CF
;
Chieng, WH
;
機械工程學系
;
Department of Mechanical Engineering
The motion cue performed by a motion simulator is restrained by the workspace of the simulator structure. A typical reasoning is then to build a large motion simulator. unless it is for entertainment, which involves in small simulators. This study proposes a novel approach to designing the washout filter of the motion control of a six degree-of-freedom motion simulator for entertainment purposes. Using information obtained from the inverse kinematics of the simulator, the workspace boundary, detected in real-time, is fed into the washout filter as a reference for the motion planning. The main focus of this approach is to make the motion cue feasible for use in a simulator with a restricted workspace, while ensuring the robustness of the driving system. In this paper, different indices are established to specify the performance of the motion cue. A classical linear washout filter was implemented and compared with the proposed washout filter using the performance indices to demonstrate the benefits of the latter.
A two-tier heterogeneous mobile ad hoc network architecture and its load-balance routing problem
(2004-08-01)
Huang, CF
;
Lee, HW
;
Tseng, YC
;
資訊工程學系
;
Department of Computer Science
The mobile ad hoc network (MANET) has attracted a lot of interest recently. However, most of the existing works have assumed a stand-alone MANET. In this paper, we propose a two-tier, heterogeneous MANET architecture which can support Internet access. The low tier of the network consists of a set of mobile hosts each equipped with a IEEE 802.11 wireless LAN card. In order to connect to the Internet and handle the network partitioning problem, we propose that the high tier is comprised of a subset of the mobile hosts, called gateways, which can access to cellular/infrastructure networks. The high tier is heterogeneous in the sense that the network interfaces in the gateway hosts could be IEEE 802.11 cards, PHS handsets, or GPRS handsets characterized by different bandwidths and latencies. Observing that the gateways could become the bottlenecks of the two-tier network, we propose a set of solutions, namely boundary-moving, host-partitioning, and probabilistic solutions, to solve the load-balance routing issue. Implementation issues/concerns of these schemes are discussed. Simulation results are presented to compare these load-balance routing schemes.
A two-tier heterogeneous mobile ad hoc network architecture and its load-balance routing problem
(2003)
Huang, CF
;
Lee, HW
;
Tseng, YC
;
資訊工程學系
;
Department of Computer Science
The mobile ad hoc network- (MANET) has attracted a lot of interest recently. However, most of the existing works have assumed a stand-alone MANET. In this paper, we propose a two-tier, heterogeneous MANET architecture which can support Internet access. The low tier of the network consists of a set of mobile hosts each equipped with a IEEE 802.11 wireless LAN card. In order to connect to the Internet and handle the network partitioning problem, we propose that the high tier is comprised of a subset of the mobile hosts, called gateways, which can access to cellular/infrastructure networks. The high tier is heterogeneous in the sense that the network interfaces in the gateway hosts could be IEEE 802.11 cards, PHS handsets, or GPRS handsets characterized by different bandwidths and latencies. Observing that the gateways could become the bottlenecks of the two-tier network, we propose a set of solutions, namely boundary-moving and host-partitioning solutions, to solve the load-balance routing issue. Implementation issues/concerns of these schemes are discussed. Simulation results are presented to compare these load-balance routing schemes.
An association mining method for time series and its application in the stock prices of TFT-LCD industry
(2004)
Huang, CF
;
Chen, YC
;
Chen, AP
;
資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
TFT-LCD is one of industries currently promoted by the "Two Trillion and Twin Star Industries Development Plan" in Taiwan. This study endeavors to find out the stock price associations between the suppliers and manufacturers in the value chain of the TFT-LCD industry by means of data mining techniques, and meanwhile, to improve the Apriori algorithm so that it can facilitate association mining of discrete data points in a time series. An efficient data mining method which consists of two phases is proposed. In the first phase, data are classified and preprocessed using the algorithm proposed by R. Agrawal et al. (1996), then Apriori algorithm is applied to extract the strong association rules. The second phase further improves the Apriori algorithm by breaking down the traditional limitation of relying on pattern matching of continuous data for disclosing stock market behavior. By mining the association rules from the discrete data points in a time series and testing the corresponding hypotheses, statistically significant outcomes can be obtained. The proposed data mining method was applied to some real time-series of the stock prices of companies in the supply chain of TFT-LCD industry in Taiwan. It is suggested that a positive correlation does not necessarily exist between the companies' stock prices in the supply chain of TFT-LCD industry. For instance the result shows that, if the stock price of Sintek Phonrotic Corp., a company in the up stream of the value chain, soars for more than 5% in a day, the stock price of Tatung, a company in the down stream of the same value chain, may not respond positively accordingly. If an investor can short the stock of Tatung on the 7th day and long it back on the 10th day after Sintek's stock price soaring for more than 5%, the annual return of investment is 199.88% with 95% confidence interval. In conclusion, the results may reveal helpful information for the investors to make leveraged arbitrage profit investing decisions, and it might be interesting to apply this proposed data mining method to the time series in other industries or problems and investigate the results further.
Behavior and surface energies of polybenzoxazines formed by polymerization with argon, oxygen, and hydrogen plasmas
(2004-11-15)
Chen, JK
;
Lin, IK
;
Ko, FH
;
Huang, CF
;
Chen, KS
Polybenzoxazine (PBZZ) thin films can be fabricated by the plasma-polymerization technique with, as the energy source, plasmas of argon oxygen or hydrogen atoms and ions. When benzoxazine (BZZ) films are polymerized through the use of high-energy argon atoms, electronegative oxygen atoms, or excited hydrogen atoms, the PBZZ films that form possess different properties aid morphologies in their surfaces. High-energy argon atoms provide a thermodynamic factor to initiate the ring-opening polymerization of BZZ and result in the polymer surface having a grid-like structure. The ring-opening polymerization of the BZZ film that is initiated by cationic species such as oxygen atoms in plasma, is propagated around nodule structures to form the PBZZ. The excited hydrogen atom plasma initiates both polymerization and decomposition reactions simultaneously in the BZZ film and Results in the formation of a porous structure on the PBZZ surface. We evaluated the surface energies of the PBZZ films polymerized by the action of these three plasmas by measuring the contact angles of diiodomethane and water droplets. The surface roughness of the films range from 0.5 to 26 nm, depending on the type of carrier gas and the plasma-polymerization time. By estimating changes in thickness, we found that tie PBZZ film synthesized by the oxygen plasma-polymerization process undergoes the slowest rate of etching in CF(4) plasma. (C) 2004 Wiley Periodicals, Inc.
Characterization of poly(vinyl pyrrolidone-co-isobutylstyryl polyhedral oligomeric silsesquioxane) nanocomposites
(2004-02-15)
Xu, HY
;
Kuo, SW
;
Huang, CF
;
Chang, FC
;
應用化學系
Poly(vinyl pyrrolidone-co-isobutyl styryl polyhedral oligomeric silsesquioxane)s (PVP-POSS) were synthesized by one-step polymerization and characterized 13 using FTIR, high-resolution H-1-NMR, solid-state C-13-NMR, Si-29-NMR, GPC, and DSC. The POSS content can be controlled by varying the POSS feed ratio. The T-g of the PVP-FOSS hybrid is influenced by three main factors: (1) a diluent role of the POSS in reducing the self-association of the PVP; (2) a strong interaction between the POSS siloxane and the PVP carbonyl, and (3) physical aggregation of nanosized POSS. At a relatively low FOSS content, the role as diluent dominates, resulting in a decrease in T-g. At a relatively high POSS content, the last two factors dominate and result in T-g increase of the PVP-POSS hybrid. (C) 2003 Wiley Periodicals, Inc.
Comparison of hydrogen bonding interaction between PMMA/PMAA blends and PMMA-co-PMAA copolymers
(2003-05-01)
Huang, CF
;
Chang, FC
;
應用化學系
;
Department of Applied Chemistry
A series of miscible PMMA/PMAA blends and PMMA-co-PMAA copolymers with different compositions were prepared in this study. T(g)s of PMMA-co-PMAA copolymers are significantly higher than average values or from the Fox equation. The proton spin-lattice relaxation time in the rotating frame (T-1p(H)) determined by high resolution solid state C-13 nuclear magnetic resonance indicates single composition-dependent from all blends and copolymers, implying a good miscibility with chain dynamics on a scale of 1-2 nm. However, T(1p)(H)s of copolymers are still smaller than those of blends, implying that degrees of homogeneity of copolymers are higher than those of blends. On the basis of Kovacs' free volume theory, the free volume of the copolymer obtained is decreased which is another indication of greater homogeneity of the copolymer than that of the corresponding blend. According to Fourier transform infrared spectroscopy analyses, the above results can be rationalized that the hydrogen bonding interaction of the copolymer is stronger than the blend. (C) 2003 Elsevier Science Ltd. All rights reserved.
Constructing control process for wafer defects using data mining technique
(2004)
Tong, L
;
Lee, H
;
Huang, CF
;
Lin, CK
;
Yang, CH
The wafer defects influence the yield of a wafer. The integrated circuits (IC) manufacturers usually use a Poisson distribution based c-chart to monitor the lot-to-lot wafer defects. As the wafer size increases, defects on wafer tend to cluster. When the c-chart is used, the clustered defects frequently cause erroneous results. The main objective of this study is to develop a hierarchical adaptive control process to monitor the clustered defects effectively and detect the wafer-to-wafer variation and lot-to-lot variation simultaneously using data mining technique.
Decentralized energy-conserving and coverage-preserving protocols for wireless sensor networks
(2005)
Huang, CF
;
Lo, LC
;
Tseng, YC
;
Chen, WT
;
資訊工程學系
The wireless sensor network is an emerging technology that may greatly facilitate human life by providing ubiquitous sensing, computing, and communication capability. However, to maintain sufficient coverage and to achieve long system lifetime are two contradicting factors in designing the topology of a sensor network. In this paper, we propose several decentralized protocols that schedule sensors' active and sleeping periods to prolong the network lifetime while maintain the sensing field sufficiently covered. The proposed protocols are based on a model similar to that of [8], but improve the results of [8] In several senses. First, our approach can significantly reduce the computational complexity incurred, and at the same time achieve better accuracy in determining the coverage of the sensing area. Second, we further enhance the results of [8] by proposing an optimization mechanism to further balance or reduce sensors' energy expenditure.
Design and implementation of two-tier Mobile Ad Hoc Networks with seamless roaming and load-balancing routing capability
(2004)
Hsu, YY
;
Tseng, YC
;
Tseng, CC
;
Huang, CF
;
Fan, JH
Due to its flexibility, Mobile Ad Hoc Network (MANET) has attracted a lot of attention recently. Most existing works, however, limit a MANET as a stand-alone network. In this paper, we propose a two-tier MANET by extending the connectivity of the MANET to the Internet. Some hosts in the MANET are equipped with cellular interfaces and are called gateways, which can provide Internet connections. Such extension would greatly improve the connectivity of MANET To maintain seamless connectivity, we modify the Mobile IP to make traversing private networks (i.e., NAT) of cellular networks possible. We also propose a load-balancing routing protocol to utilize the cellular interfaces of gateways, which are likely to be bottlenecks to the Internet. A prototype is implemented and performance results obtained from the testbed is reported.
Design of the swinging-block and turning-block mechanism with special reference to the mechanical advantage
(2004-03-01)
Yu, WJ
;
Huang, CF
;
Chieng, WH
;
機械工程學系
;
Department of Mechanical Engineering
This study describes a novel and complete solution for turning-block and swinging-block design with particular reference to the maximal average mechanical advantage over a specific swing angle span of the output link. The method yields an optimal set of link lengths for the turning-block and the swinging-block mechanisms. The torque was integrated with respect to the crank swing angle that yields a transmission energy form to maximize the average mechanical advantage. The optimal design solution is determined from the stationary value of the transmission energy. Results of this study can provide a valuable reference for efforts to achieve the high precision and high torque required in the mechanical design.
Effect of bisphenol A on the miscibility, phase morphology, and specific interaction in immiscible biodegradable poly(epsilon-caprolactone)/poly(L- lactide) blends
(2006-04-15)
Kuo, SW
;
Huang, CF
;
Tung, YC
;
Chang, FC
;
應用化學系
We have investigated the enhancement in miscibility, upon addition of bisphenol A (BPA) of immiscible binary biodegradable blends of poly(epsilon-caprolactone) (PCL) and poly(L-lactide) (PLLA). That BPA is miscible with both PCL and PLLA was proven by the single value of T-g observed by differential scanning calorimetry (DSC) analyses over the entire range of compositions. At various compositions and temperatures, Fourier transform infrared spectroscopy confirmed that intermolecular hydrogen bonding existed between the hydroxyl group of BPA and the carbonyl groups of PCL and PLLA. The addition of BPA enhances the miscibility of the immiscible PCL/PLLA binary blend and transforms it into a miscible blend at room temperature when a sufficient quantity of the BPA is present. In addition, optical microscopy (OM) measurements of the phase morphologies of ternary BPA/PCL/ PLLA blends at different temperatures indicated an upper critical solution temperature (UCST) phase diagram, since the Delta K effect became smaller at higher temperature (200 degrees C) than at room temperature. An analysis of infrared spectra recorded at different temperatures correlated well with the OM analyses. (c) 2006 Wiley Periodicals, Inc.
Fabrication of biomimetic super-amphiphobic surfaces through plasma modification of benzoxazine films
(2006-03-03)
Wang, CF
;
Chiou, SF
;
Ko, FH
;
Chou, CT
;
Lin, HC
In this study, a method for producing super-amphiphobic surfaces through plasma modification of benzoxazine films is presented. Microroughening and fluorination of the benzoxazine films occurs during the plasma treatment process and a rugged surface with a micro/nano binary structure is formed. The combined effect of low surface energy and substrate roughness results in high advancing contact angles (157 degrees for water, 152 degrees for diiodomethane) and low contact angle hysteresis.
High thermal stability metal gate with tunable work function
(2004)
Huang, CF
;
Tsui, BY
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
It has been reported that the work function of Ta-Pt alloys is tunable and Ta-Pt is a possible gate material for CMOS devices. In this work, we demonstrate that the Ta-Pt alloy is thermally stable up to 900degreesC. The impact of oxygen contamination and thermal stress on the stability of the MOS structure with the alloy gate is also discussed. It is concluded that the Ta-Pt alloy is a good candidate for gate electrode in the nanoscale CMOS regime and is compatible with the conventional self-aligned process.
Homopolymerization and copolymerization of tert-butyl methacrylate and norbornene with nickel-based methylaluminoxane catalysts
(2004-05-05)
Huang, CF
;
Wang, SK
;
Kuo, SW
;
Huang, WJ
;
Chang, FC
The homopolymerization and copolymerization of tert-butyl methacrylate (tBMA) and norbornene (NB) with nickel(II) acetylacetonate in combination with methylaluminoxane were systematically investigated. This catalytic system showed high activity toward the homopolymerization of both NB and tBMA. For these copolymerizations, activity was gradually lost with an addition of tBMA to NB or of NB to tBMA. This result was qualitatively explained with the trigger coordination mechanism. Furthermore, the determination of the reactivity ratios indicated a significantly whigher reactivity for NB than for tBMA (r(NB) = 4.14 and r(tBMA) = 0.097), and this was interpreted by the coordination mechanism. The synthesized acrylate/NB copolymers exhibited glass-transition temperatures of 100-250degreesC. The absence of crystallinity and the homogeneous repartition of the monomer units along the main chain yielded products with high transparency and high stability. (C) 2004 Wiley Periodicals, Inc.
Hydrogen bonding interactions and miscibility between phenolic resin and octa(acetoxystyryl) polyhedral oligomeric silsesquioxane (AS-POSS) nanocomposites
(2006-02-15)
Kuo, SW
;
Lin, HC
;
Huang, WJ
;
Huang, CF
;
Chang, FC
We have synthesized a polyhedral oligomeric silisesquioxane (POSS) derivative containing eight acetoxystyryl functional groups [octa(acetoxystyryl)octasilsesquioxane (AS-POSS)] and then blended it with phenolic resin to form nanocomposites stabilized through hydrogen bonding interactions between the phenolic resin's hydroxyl group and the AS-POSS derivative's carbonyl and siloxane groups. One-and two-dimensional infrared spectroscopy analyses provided positive evidence for these types of hydrogen bonding interactions. In addition, we calculated the interassociation equilibrium constant, based on the Painter-Coleman association model (PCAM), between phenolic resin and POSS indirectly from the fraction of hydrogen-bonded carbonyl groups; quantitative analyses indicate that the hydroxyl-siloxane interassociation from the PCAM is entirely consistent with the classical Coggesthall and Saier (C and S) methodology. From a thermal analysis, we observed that the miscibility between phenolic and AS-POSS occurs at a relatively low AS-POSS content, which characterizes this mixture as a polymer nanocomposite system. (c) 2006 Wiley Periodicals, Inc.
Increasing the throughput of multihop Packet Radio Networks with power adjustment
(2001)
Huang, CF
;
Tseng, YC
;
Wu, SL
;
Sheu, JP
;
資訊工程學系
The Packet Radio Network (PRN) is an attractive architecture to support mobile and wireless communication. Although the code assignment problem has been studied extensively on PRN, we observe in this paper that the power control problem has been ignored by most works, but may have significant impact on performance. By power control, we mean that the transmission ranges of stations are tunable. We show given a PRN in which each host already received a code, how to adjust the powers of stations to control/improve the topology of the PRN without violating the original code assignment. Several schemes are proposed. Through simulations, we demonstrate that although the code assignment problem is NP-complete and thus computationally very expensive, using our power adjustment schemes can easily improve the network performance by about 20% with polynomial costs.