Showing papers by "Chung Yuan Christian University published in 2000"

Economic ordering policy of deteriorated item for vendor and buyer: An integrated approach

Abstract: This study develops an economic ordering policy of a deteriorating item with a constant production and demand rate. By considering the view of both the vendor and buyer, a mathematical model subject to single-vendor-single-buyer and multiple deliveries per order is developed. It can be shown that the integrated approach results in an impressive cost-reduction compared with an independent decision by the buyer.

Using principal component analysis in process performance for multivariate data

Abstract: Quality measures can be used to evaluate a process’s performance. Analyzing related quality characteristics such as weight, width and height can be combined using multivariate statistical techniques. Recently, multivariate capability indices have been developed to assess the process capability of a product with multiple quality characteristics. This approach assumes multivariate normal distribution. However, obtaining these distributions can be a complicated task, making it difficult to derive the needed confidence intervals. Therefore, there is a need to develop one robust method to deal with the process performance on non-multivariate normal data. Principal component analysis (PCA) can transform the high-dimensional problems into lower dimensional problems and provide sufficient information. This method is particularly useful in analyzing large sets of correlated data. Also, the application of PCA does not require multivariate normal assumption. In this study, several capability indices are proposed to summarize the process performance using PCA. Also, the corresponding confidence intervals are derived. Real-world case studies will illustrate the value and power of this methodology.

Separate structure extended gate H+-ion sensitive field effect transistor on a glass substrate

Abstract: In our research, glass was used as a substrate for an H + ion sensitive field effect transistor (ISFET). The sensitive characteristics of five structures for separate extended gate ion sensitive field effect transistors (EGFET) were studied. The components included tin oxide (SnO 2 )/aluminum/micro slide glass, tin oxide/aluminum/corning glass, indium tin oxide (ITO) glass, tin oxide/indium tin oxide glass and tin oxide/micro slide glass. Indium tin oxide (ITO) thin film was first time used as an H + ion sensitive film, which has a linear pH Nerstern response sensitivity, about 58 mV/pH, between pH 2 and 12. In addition, the sensing area effect of the tin oxide/glass, tin oxide/ITO glass and ITO glass structure is discussed. The results show that the tin oxide/ITO glass structure EGFET has the best drift, hysteresis and sensing area characteristics.

Optimal design for fuzzy controllers by genetic algorithms

Abstract: Fuzzy control has been applied to various industrial processes; however, its control rules and membership functions are usually obtained by trial and error. Proposed in this paper is an optimal design for membership functions and control rules simultaneously by a genetic algorithm (GA). GAs are search algorithms based on the mechanics of natural selection and natural genetics. They are easy to implement and efficient for multivariable optimization problems, such as fuzzy controller design. The simulation result shows that the fuzzy controller thus designed can achieve good performance merely by using a few fuzzy variables.

Optimal planning of large passive-harmonic-filters set at high voltage level

Abstract: This paper proposes the optimal planning of large passive-harmonic-filters set at high voltage level based on multi-type and multi-set of filters, from which the types, set numbers, capacities and the important parameters of filters are well determined to satisfy the requirements of harmonic filtering and power factor. Four types of filters, namely single-tuned filter, second-order, third-order and C-type damped filters are selected for the planning. Firstly, the characteristics of filters are analyzed. The cost function and the constraints of filters and system are constructed for formulating the optimization problem of the planning of filters. Secondly, the simulated-annealing (SA) algorithm for searching the optimal solution of planning of filters is developed. Finally, three cases of filter planning are presented to show that the superiority and availability of the SA algorithm and proposed planning results of filters.

A flame-retardant phosphate and cyclotriphosphazene-containing epoxy resin: Synthesis and properties

Abstract: A novel flame-retardant epoxy resin, (4-diethoxyphosphoryloxyphenoxy)(4-glycidoxyphenoxy)cyclotriphosphazene (PPCTP), was prepared by the reaction of epichlorohydrin with (4-diethoxyphosphoryloxyphenoxy)(4-hydroxyphenoxy)cyclotriphosphazene and was characterized by Fourier transform infrared, 31P NMR, and 1H NMR analyses. The epoxy resin was further cured with diamine curing agents, 4,4′-diaminodiphenylmethane (DDM), 4,4′-diaminodiphenylsulfone (DDS), dicyanodiamide (DICY), and 3,4′-oxydianiline (ODA), to obtain the corresponding epoxy polymers. The curing reactions of the PPCTP resin with the diamines were studied by differential scanning calorimetry. The reactivities of the four curing agents toward PPCTP were in the following order: DDM > ODA > DICY > DDS. In addition, the thermal properties of the cured epoxy polymers were studied by thermogravimetric analysis, and the flame retardancies were estimated by measurement of the limiting oxygen index (LOI). Compared to a corresponding Epon 828-based epoxy polymer, the PPCTP-based epoxy polymers showed lower weight-loss temperatures, higher char yields, and higher LOI values, indicating that the epoxy resin prepared could be useful as a flame retardant. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 972–981, 2000

Adaptive backstepping control for linear induction motor drive to track periodic references

Abstract: An adaptive backstepping controller is proposed to control the mover position of a linear induction motor (LIM) drive to track periodic reference inputs in this study. First, the feedback linearisation theory is used to decouple the thrust force and the flux amplitude of the LIM. Then, an integral-proportional (IP) position controller is designed according to the estimated plant model to match the prescribed periodic step-command tracking specifications for the LIM drive. Moreover, a feedforward control is added to the IP control system for the tracking of periodic sinusoidal and triangular reference inputs. Although theoretically the feedforward control can track any time-varying reference, the robust control performance is degenerate when the uncertainties occur in the controlled plant. Therefore, an adaptive backstepping approach is proposed to obtain the robustness for uncertainties. With the proposed adaptive backstepping controller, the mover position of the LIM drive possesses the advantages of good transient control performance and robustness to uncertainties for the tracking of periodic reference inputs. The effectiveness of the proposed control scheme is verified by both the simulated and experimental results.

Universal current-mode OTA-C biquad with the minimum components

Abstract: A universal current mode operational transconductance amplifier-capacitor (OTA-C) biquad with three inputs and four outputs employing the minimum of components: only two OTAs and only two grounded capacitors is presented. The proposed circuit offers the following advantageous features: realization of low-pass, bandpass, high-pass, notch; and all-pass signals from the same simple configuration, employment of two grounded capacitors ideal for integration and low-sensitivity performance.

Comparison between Spray Towers with and without Fin Coils for Air Dehumidification Using Triethylene Glycol Solutions and Development of the Mass-Transfer Correlations

Abstract: Spray towers with and without fin coils were compared for their efficiency in air dehumidification using triethylene glycol (TEG) solutions. Experiments were conducted using different air flow rates, liquid flow rates, temperature and air humidities, and aqueous TEG solution concentrations. Theoretically, an absorber with fin coils reduces the temperature of the desiccant solution, which leads to a greater amount of water vapor removal from the air. It was evident that the performance of the spray tower with fin coils was better than that of the spray tower without fin coils under similar operating conditions. Mass-transfer correlations were developed for both systems, which considered the changes in gas−liquid flow ratio, temperature, TEG concentration, and some physical properties. A dimensional analysis of the process variables was carried out using the Buckingham Pi method to obtain the dimensionless groups of the correlations. Most of the values predicted by the correlations were within ±10% of the e...

Solubility of Nitrous Oxide in Alkanolamine Aqueous Solutions

Abstract: The solubility of nitrous oxide (N2O) in alkanolamine aqueous solutions has been measured at (30, 35, and 40) °C. The systems studied are monoethanolamine, diethanolamine, diisopropanolamine, triethanolamine, and 2-amino-2-methyl-1-propanol aqueous solutions. The concentration of amine for monoethanolamine ranges from (1 to 6) kmol·m-3 and for other amines from (0.5 to 3) kmol·m-3. The accuracy of the measurement is estimated to be ± 2%. A semiempirical model of the excess Henry's constant proposed by Wang et al. (1992) was used to correlate the solubility of N2O in amine solutions. The parameters of the correlation were determined from the measured solubility data and the available data in the open literature. For a wide temperature range from (15 to 75) °C, the obtained correlation has been shown to represent reasonably the solubility of N2O in six amine aqueous solutions: MEA, DEA, DIPA, TEA, MDEA, and AMP. For the purpose of process design, the obtained correlations are, in general, satisfactory for ...

A secure data hiding technique with heterogeneous data-combining capability for electronic patient records

Abstract: It is an enabling technology to transmit electronic patient records (EPR) across distances to hospitals and countries through the Internet. However, since EPR is a highly personal medical documentation, transmission of secure EPR is required to reduce the risk of security breach on the network and prevent accessing of data by unauthorized end-users. Here, the authors propose a bi-polar multiple-base data hiding technique, where a pixel value difference between an original image and its default JPEG (Joint Photographic Experts Group) lossy decompressed image is taken to be a number conversion base. The authors hide doctors' digital seals and the EPR data within a still image by using this approach. The still image could be the mark of a hospital to identify where the EPR comes from. The doctors' digital seals are essential to the authentication of EPR. A diagnostic report and a biomedical signal such as an electrocardiogram (ECG) can also be hidden in the image. The proposed approach allows multiple data types to be hidden in the same image. All the data can be separated and restored perfectly by the intended users. In addition, the proposed data hiding technique has higher peak signal to noise ratio than that of using default JPEG alone. Thus, the transparency of the hidden image and the invisibility of the EPR data are guaranteed.

Robust control of linear synchronous motor servodrive using disturbance observer and recurrent neural network compensator

Abstract: Robust control of a permanent magnet (PM) linear synchronous motor (LSM) servodrive is achieved by using a disturbance observer and a recurrent neural network (RNN) compensator. An integral-proportional (IP) controller is introduced to control the mover position of the LSM. The IP position controller is designed according to the estimated mover parameters to match the time-domain command tracking specifications. A disturbance observer is implemented and the observed disturbance force is fed forward to increase the robustness of the LSM servodrive. Moreover, to increase the control performance of the LSM servodrive under the occurrence of large disturbance, a RNN compensator is proposed to reduce the influence of parameter variations and external disturbances of the LSM servodrive system as a force controller. In addition, a dynamic backpropagation algorithm is developed to train the RNN online using the delta adaptation law. The effectiveness of the proposed control schemes is demonstrated by some simulated and experimental results.

Study on separative structure of EnFET to detect acetylcholine

Abstract: In this study, our laboratory used a separative structure of extended gate field effect transistor (EGFET) to detect pH value and constructed an enzyme modified field effect transistor (EnFET) by coupling them with a membrane containing immobilized acetylcholinesterase (AcChE). The enzyme-catalyzed hydrolysis reaction of acetylcholine seemed to be resulted in the pH change of the membrane due to the formation of acetic acid. This structure has a lot of advantages, such as being insensitive toward light, being simple to in its passivation and package, and the flexibility of shape in the extended gate area, etc. In addition, it is easier to fabricate and package the sensors, and the measurement is simple for the application of disposable biosensor.

Decoupled stator-flux-oriented induction motor drive with fuzzy neural network uncertainty observer

Abstract: A stator-flux-oriented induction motor drive using online rotor time-constant estimation with a robust speed controller is introduced in this paper. The estimation of the rotor time constant is made on the basis of the model reference adaptive system using an energy function. The estimated rotor time-constant is used in the current-decoupled controller, which is designed to decouple the torque and flux in the stator-flux-field-oriented control. Moreover, a robust speed controller, which is comprised of an integral-proportional speed controller and a fuzzy neural network uncertainty observer, is designed to increase the robustness of the speed control loop. The effectiveness of the proposed control scheme is demonstrated by simulation and experimental results.

Implications of recent measurements of hadronic charmless B decays

Abstract: The implications of recent CLEO measurements of hadronic charmless $B$ decays are discussed. (i) Employing the Bauer-Stech-Wirbel (BSW) model for form factors as a benchmark, the $\stackrel{\ensuremath{\rightarrow}}{B}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ data indicate that the form factor ${F}_{0}^{B\ensuremath{\pi}}(0)$ is smaller than that predicted by the BSW model, whereas the data of $\stackrel{\ensuremath{\rightarrow}}{B}\ensuremath{\omega}\ensuremath{\pi},$ ${K}^{*}\ensuremath{\eta}$ imply that the form factors ${A}_{0}^{B\ensuremath{\omega}}(0),$ ${A}_{0}^{{\mathrm{BK}}^{*}}(0)$ are greater than the BSW model values. (ii) The tree-dominated modes $\stackrel{\ensuremath{\rightarrow}}{B}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}},$ ${\ensuremath{\rho}}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}},$ $\ensuremath{\omega}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ imply that the effective number of colors ${N}_{c}^{\mathrm{eff}}(\mathrm{LL})$ for $(V\ensuremath{-}A)(V\ensuremath{-}A)$ operators is preferred to be smaller, while the current limit on $\stackrel{\ensuremath{\rightarrow}}{B}\ensuremath{\varphi}K$ shows that ${N}_{c}^{\mathrm{eff}}(\mathrm{LR})g3.$ The data of $\stackrel{\ensuremath{\rightarrow}}{B}K{\ensuremath{\eta}}^{\ensuremath{'}}$ and ${K}^{*}\ensuremath{\eta}$ clearly indicate that ${N}_{c}^{\mathrm{eff}}(\mathrm{LR})\ensuremath{\gg}{N}_{c}^{\mathrm{eff}}(\mathrm{LL}).$ (iii) In order to understand the observed suppression of ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and nonsuppression of $K\ensuremath{\pi}$ modes, both being governed by the form factor ${F}_{0}^{B\ensuremath{\pi}},$ the unitarity angle $\ensuremath{\gamma}$ is preferred to be greater than $90\ifmmode^\circ\else\textdegree\fi{}.$ By contrast, the new measurement of ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ no longer strongly favors $\mathrm{cos}\ensuremath{\gamma}l0.$ (iv) The observed pattern ${K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}\ensuremath{\sim}{K}^{0}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\sim}\frac{2}{3}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ is consistent with the theoretical expectation: The constructive interference between electroweak and QCD penguin diagrams in the ${K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ mode explains why $\mathcal{B}{(B}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0})g\frac{1}{2}\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}).$ (v) The observation ${N}_{c}^{\mathrm{eff}}(\mathrm{LL})l3l{N}_{c}^{\mathrm{eff}}(\mathrm{LR})$ and our preference for ${N}_{c}^{\mathrm{eff}}(\mathrm{LL})\ensuremath{\sim}2$ and ${N}_{c}^{\mathrm{eff}}(\mathrm{LR})\ensuremath{\sim}6$ are justified by a recent perturbative QCD calculation of hadronic rare $B$ decays in the heavy quark limit. (vi) The sizable branching ratios of ${K}^{*}\ensuremath{\eta}$ and the enormously large decay rates of $K{\ensuremath{\eta}}^{\ensuremath{'}}$ indicate that it is the constructive interference of two comparable penguin amplitudes rather than the mechanism specific to the ${\ensuremath{\eta}}^{\ensuremath{'}}$ that accounts for the bulk of $\stackrel{\ensuremath{\rightarrow}}{B}{\ensuremath{\eta}}^{\ensuremath{'}}K$ and $\ensuremath{\eta}{K}^{*}$ data. (vii) The new upper limit set for ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\omega}{K}^{\ensuremath{-}}$ no longer imposes a serious problem for the factorization approach. It is anticipated that $\mathcal{B}{(B}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\omega}{K}^{\ensuremath{-}})\ensuremath{\gtrsim}2\mathcal{B}{(B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{K}^{\ensuremath{-}})\ensuremath{\sim}2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}.$ (viii) An improved and refined measurement of $\stackrel{\ensuremath{\rightarrow}}{B}{K}^{*\ensuremath{-}}{\ensuremath{\pi}}^{+},$ ${K}^{0}{\ensuremath{\pi}}^{0}$ is called for in order to resolve the discrepancy between theory and experiment. Theoretically, it is expected that ${K}^{0}{\ensuremath{\pi}}^{0}\ensuremath{\sim}\frac{1}{2}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ and ${K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}\ensuremath{\sim}3{K}^{*\ensuremath{-}}{\ensuremath{\pi}}^{+}.$

Quality driven gold washing adaptive vector quantization and its application to ECG data compression

Abstract: The gold washing (GW) adaptive vector quantization (AVQ) (GW-AVQ) is a relatively new scheme for data compression. The adaptive nature of the algorithm provides the robustness for wide variety of the signals. However, the performance of GW-AVQ highly dependent on a preset parameter called distortion threshold (dth) which must be determined by experience or trial-and-error. The authors propose an algorithm that allows them to assign an initial dth arbitrarily and then automatically progress toward a desired dth according to a specified quality criterion, such as the percent of root mean square difference (PRD) for electrocardiogram (ECG) signals. A theoretical foundation of the algorithm is also presented. This algorithm is particularly useful when multiple GW-AVQ codebooks and, thus, multiple dth's are required in a subband coding framework. Four sets of ECG data with entirely different characteristics are selected from the MIT/BIH database to verify the proposed algorithm. Both the direct GW-AVQ and a wavelet-based GW-AVQ are tested. The results show that a user specified PRD can always be reached regardless of the ECG waveforms, the initial selection of dth or whether a wavelet transform is used in conjunction with the GW-AVQ. An average result of 6% in PRD and 410 bits/s in compressed data rate is obtained with excellent visual quality.

Synchronization with message embedded for generalized Lorenz chaotic circuits and its error analysis

Abstract: The main concern in this brief is how to design a better receiver structure and its synchronization error analysis. By exploiting a skew-symmetric type property existing in generalized Lorenz chaotic systems, we propose a novel receiver design for synchronizing the transmitter-receiver pair. Error analysis carried out by the Lyapunov direct method explicitly shows the relation among the magnitudes of the synchronization error, coupling noise, transmitter parameters, and signals. If no noise or message exists in the coupling channel, then exponential synchronization can be achieved for all state signals. As a guideline from the error analysis, a more suitable receiver can be successfully designed and implemented. Experiments are carried out on the circuit of the transmitter-receiver pair to show the performance of the synchronization and secure communication.

New configuration for realizing universal voltage-mode filter using two current feedback amplifiers

Abstract: A new universal biquadratic filter configuration using two current-feedback amplifiers (CFAs) is presented. The circuit has three inputs and one low-impedance output and can realize all the standard filter functions, that is, highpass, bandpass, lowpass, notch, and allpass filters, without changing the passive elements. The proposed circuit has no requirements for component matching conditions and uses only four passive components. The center frequency and bandwidth can be orthogonally controllable. Also, the active and passive sensitivities are low.

Studies on the synthesis and properties of thermotropic liquid crystalline polycarbonates. VII. Liquid crystalline polycarbonates and poly(ester‐carbonate)s derived from various mesogenic groups

Abstract: Three series of thermotropic liquid crystalline polycarbonates and poly(ester-carbonate)s were prepared by solution polycondensation of 4,4′-biphenyldiol (BP), 4′-hydroxybiphenyl-4-hydroxybenzoate (HHB), or 4-hydroxyphenyl-4″-hydroxybiphenyl-4′-carboxylate (HHBP), as mesogenic unit, with 1,10-bis(p-hydroxybiphenoxy)decane (N10), bisphenol A (BPA), 4,4′-dihydroxy-diphenyl ether (BPO), 4,4′-[phenylbis(oxy)]bisphenol (BPOO), methylhydroquinone (MeHQ), or phenylhydroquinone (PhHQ). One series of cholesteric poly(ester-carbonate)s were also prepared by using HHBP, the aromatic diols mentioned above and isosorbide as the chiral moiety. All polycondensations were implemented in pyridine by using triphosgene as the condensation agent. The synthesized polycarbonates were characterized by viscometer, FTIR, DSC, TGA measurements, polarizing microscopy equipped with a heating stage, and WAXD powder pattern. In this study, it was found that the liquid crystalline properties of polycarbonates strongly rely on the mesogenic unit applied. HHBP-series exhibits a wide temperature region of liquid crystalline (LC) phase even with 50% of bisphenol A (BPA), which is a V-shaped structure and usually destroys liquid crystalline properties. In addition, homopolycarbonate with HHBP structure possesses extraordinarily low phase-transition temperature and wide liquid crystalline phase range, due to its asymmetric structure. This asymmetric structure results in head-to-tail, head-to-head, and tail-to-tail random conformation of polymer chain. The isosorbide containing poly(ester-carbonate)s formed cholesteric phase, which showed homogeneous blue, green, or red Grandjean texture upon shearing in molten state and the Grandjean texture could be frozen easily while quenching the sample to the room temperature. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1852–1860, 2000

Polyphosphazene Electrolytes. 2. Synthesis and Properties of New Polymer Electrolytes Based on Poly((amino)[(2-methoxyethoxy)ethoxy])phosphazenes

Abstract: A series of ether group and amino group cosubstitutent phosphazene copolymers was synthesized and characterized by a combination of NMR, elemental analysis, and FTIR spectroscopy. The length of the alkyl group in the amino side chain and the content of the methoxyethoxyethoxy (MEE) substituent on the polymer properties were varied. Dynamic mechanical analysis (DMA) demonstrated that the cosubstitutent polymers prepared have better mechanical properties than the ether homopolyphosphazene, poly[bis(2-methoxyethoxy)ethoxy]phosphazene, MEEP. The copolymers that possessed multiple electron-donor coordination sites, nitrogen and oxygen atoms, were complexed with various amounts of lithium perchlorate (LiClO4) to form polymer electrolytes. The ionic conductivity of the polymer electrolytes were determined by an impedance analyzer in a temperature range of 30−80 °C. According to those results, the conductivities of the prepared polymer electrolytes increased according to the rise in the MEE side chain contents an...

Surface Modifications of Expanded Poly(tetrafluoroethylene) Sheets Assisted by CO2 Antenna Coupling Microwave Plasma

Abstract: Surfaces of the expanded poly(tetrafluoroethylene) (ePTFE) sheets were chemically modified with the assistance of CO2 cold plasma generated by antenna coupling guided microwave. The plasma pretreated ePTFE surface did not obviously change in terms of morphology of nodes structure but increased surface tension and promoted subsequent capability to graft polymerization with acrylic acid (AAc). The modified ePTFE were then characterized using FTIR-ATR and X-ray photoelectron spectroscopy (XPS). Morphologies of ePTFE surfaces and the cross-sectioned side of AAc-grafted ePTFE were examined by SEM and FTIR microscopy. Experimental results indicated that AAc penetrated to a depth of ca. 60 μm and bonded on the surfaces of nodes and fibrils. Generation of COF species on the ePTFE surfaces by CO2 plasma contributed to this initiation effect. Current data also supported that plasma generated by the CO2 antenna-coupling microwave system could efficiently activate the exposed ePTFE surfaces of interior fibrils and no...