Showing papers by "National Tsing Hua University published in 1983"
TL;DR: In this article, the shifted Legendre polynomial series is employed to solve variational problems and the solution is carried out by using an operational matrix for integrating the shift Legendre vector.
Abstract: The shifted Legendre polynomial series is employed to solve variational problems. The solution is carried out by using an operational matrix for integrating the shifted Legendre polynomial vector. Variational problems are reduced to solving algebraic equations. Two illustrative examples are given, and the computational results obtained by Legendre series direct method are compared with the exact solutions.
129 citations
TL;DR: In this paper, the acid-base solid, TiO2ZrO2, was examined as a potential catalyst for nonoxidative dehydrogenation of ethylbenzene.
98 citations
TL;DR: A concept of k-node-fault testability is introduced and a sufficient and almost necessary condition for testability as well as the test procedure is presented, which depends only on the graph of the circuit, not on the element values.
Abstract: A concept of k -node-fault testability is introduced. A sufficient and almost necessary condition for testability as well as the test procedure is presented. This condition is further evolved to a necessary and almost sufficient topological condition for testability. A unique feature of this condition is that it depends only on the graph of the circuit, not on the element values. Based on this condition, a design of testability can be established.
90 citations
TL;DR: The dispersion of freshly prepared catalysts decreased with the palladium content and the measured dispersions were used to calibrate the peaks of hydrogen sorption on palladium using a temperature controlled flow system as mentioned in this paper.
59 citations
TL;DR: The findings suggest that some pharmacological effects of snake venom PLA2 enzymes are due to a non-enzymatic action, suggesting two distinct but perhaps overlapping active sites.
52 citations
TL;DR: The characteristics and dynamics of an abruptly expanded flow in a model combustion chamber (combustor) were investigated experimentally in this paper, where the wall pressure measurements were carried out with a laser-Doppler anemometer (LDA).
Abstract: The characteristics and dynamics of an abruptly expanded flow in a model combustion chamber (combustor) were investigated experimentally. The combustion chamber consisted of a plexiglass, circular duct with a suddenly enlarged section followed by a nozzle. The Reynolds number, based on the inlet duct diameter and center velocity, was 64,000. The wall pressure measurements were carried out with a laser-Doppler anemometer (LDA). Detailed profiles of mean velocities, turbulent intensities, turbulent shear stresses, and wall pressure distribution were developed. The dividing streamline, the reattachment point, and the magnitudes of the mean kinetic energy and turbulent kinetic energy were also determined.
50 citations
TL;DR: In this paper, a mathematical model for solvent sublation column operation is presented, and satisfactry aggreement is obtained for naphthalene and phenanthrene removal from aqueous systems.
Abstract: Naphthalene and phenanthrene are readily removed from aqueous systems by solvent sublation into mineral oil. The process is slightly enhanced by added salts, and slightly retarded by acetone and ethanol. The naphthalene results are used to test a mathematical model for solvent sublation column operation; satisfactry aggreement is obtained.
46 citations
TL;DR: It is concluded that charge alone does not account for differences in toxicity and there are at least two distinct active sites in both enzymes, one being primarily responsible for enzymatic activity and the other(s) associated with lethal and pharmacological effects of the protein.
41 citations
TL;DR: In this paper, the generalized Fenchel theorem was proved for the optimization problem of a set function defined on a family of measurable subsets in an atomless finite measure space (X, a, m).
38 citations
TL;DR: In this paper, the superconductivity and crystallographic data for the MM′X ternary compounds with M = Ti, Zr, or Hf, M′ = Ru or Os, and X = P or As are presented.
Abstract: Recent superconductivity and crystallographic data for the MM′X ternary compounds with M = Ti, Zr, or Hf, M′ = Ru or Os, and X = P or As are presented. Moderate to high superconducting transition temperatures (T
c
's)are exhibited by the ZrRuSi-type hexagonal phase which is found to be metastable at low temperatures. The low-temperature phase of ZrRuP has the TiNiSi-type orthorhombic structure and exhibits superconductivity at 3.9K. The low-temperature phase of HfRuAs has the TiFeSi-type orthorhombic superstructure and remains normal at 1.0K. TiRuAs exists only with the superstructure and remains normal at 0.35K. The details of these various structural modifications point to the importance of undistorted zig-zag chains of metal atoms for the occurrence of superconductivity in these compounds. The lowT
c
for TiRuP and the absence of superconductivity for TiOsP above 0.35K are not accounted for by these structural modifications.
30 citations
TL;DR: The extremely high computational speed of PAM in securing sensitivity informations was demonstrated by two illustrative kinetic examples and the problem of utilizing sensitivity information to unravel the functional dependence of a species concentration upon rate coefficients, to simplify a complex reaction model, and to elucidate mechanistic details of a reaction process was examined.
Abstract: A new approach, the method of polynomial approximations (PAM), to the sensitivity analysis in chemical kinetics is presented. The method is based on first dividing the time domain of interest into subintervals, and then, within each subinterval, using low-degree interpolation polynomials to mimic the system temporal behavior. This procedure forces all parametric dependences of the system to reside in the expansion coefficients and transforms the differential sensitivity equations into a set of algebraic ones. The major computational effort of PAM is proportional to the number of components in the system, not to the number of parameters. In addition, higher order sensitivity coefficients in PAM can be generated quite readily once first-order ones are known. The information required to divide the time domain comes from a preliminary simulation study of the system temporal behavior, which is always available in any kind of modeling studies. Typically, for an interpolation polynomial of degree 3–4, only 10–20 subintervals are needed to attain satisfactory accuracy. The application of PAM is well suited to large-scale kinetic models, especially when an inexpensive scanning of the system sensitivity behavior is desired. The extremely high computational speed of PAM in securing sensitivity informations was demonstrated by two illustrative kinetic examples. Furthermore the problem of utilizing sensitivity information to unravel the functional dependence of a species concentration upon rate coefficients, to simplify a complex reaction model, and to elucidate mechanistic details of a reaction process was examined in detail.
TL;DR: In this paper, annealing, ion beam mixing and two-step anneal were used to induce interfacial reactions between iron thin films and silicon substrate, resulting in epitaxial islands as large as 40 μm in size.
Abstract: Isothermal annealing, two step annealing and ion beam mixing were performed to induce interfacial reactions between iron thin films and silicon substrate. Both orthorhombic and tetragonal FeSi 2 were found to grow epitaxially on (lll)Si with orthorhombic FeSi 2 being the predominant phase. No epitaxial growth of FeSi 2 on (001)Si was detected. Epitaxial islands as large as 40 μm in size were formed by a scheme combining ion beam mixing and two step annealing.
TL;DR: In this paper, it was found that approximately 60% of the Ni is in fluctuations that resemble platelets on (100) planes, and rods, with a spacing (6-7 A) similar to the clusters that are found after quenching and aging.
TL;DR: In this paper, the physical characteristics of SnOx(x≈2) films deposited onto Pyrex glass substrates by chemical vapour deposition are studied, and it is shown that the electrical conductivity of the 600 °C films is mainly controlled by the variation in the SnCl4 vapour flow rate.
TL;DR: A method for the control of time delay systems represented by moving models established by the use of block pulse functions permits the linear feedback control law to be applied to non-linear systems.
Abstract: A method for the control of time delay systems is presented. The systems are represented by moving models established by the use of block pulse functions. This approach permits the linear feedback control law to be applied to non-linear systems. The moving model representation and the optimal feedback control of time delay systems are presented to demonstrate that the method exhibits satisfactory results.
TL;DR: In this paper, an equation aux derivees partielles representant le systeme lineaire reparti is transformee en un ensemble d'equations differencelles ordinaires par le developpement en polynome de Legendre des signaux d'entree et de sortie.
Abstract: L'equation aux derivees partielles representant le systeme lineaire reparti est transformee en un ensemble d'equations differentielles ordinaires par le developpement en polynome de Legendre des signaux d'entree et de sortie. Le critere de performance est exprime en fonction des coefficients du developpement, et on transforme le probleme de commande optimale en un probleme a deux points limites en appliquant le principe du maximum
TL;DR: In this article, the formation of epitaxial CoSi2 on silicon by both conventional and two-step annealing of cobalt thin films on silicon was studied by transmission electron microscopy.
TL;DR: In this paper, a rigorous elastodynamic hybrid-displacement finite element procedure for a safety analysis of fast rotating disks with mixed-mode cracks is presented, where the proper crack-tip singularities are taken into consideration and the interelement displacement compatibility conditions are still satisfied.
TL;DR: In this article, the ion-beam-induced microstructural changes in nickel thin films on silicon were investigated by Rutherford backscattering spectrometry and transmission electron microscopy, and the results of post-implantation annealing showed major differences from those obtained for directly annealed samples.
TL;DR: In this article, the title compound, a masked 3,6-di-n-propyl-o-benzoquinone, was synthesized from 3, 6-d-npropylcatechol in 82% yield.
Abstract: The title compound, a masked 3,6-di-n-propyl-o-benzoquinone, was synthesized from 3,6-di-n-propylcatechol in 82% yield. Its Diels-Alder reactions with methyl propiolate, phenylacetylene, 1-octyne, dimethyl acetylenedicarboxylate, diphenylacetylene and 3-hexyne were studied. The yields of the adducts were excellent except for the last two cases in which the unimolecular decomposition of the title compound to generate 3,6-di-n-propylcatechol methylene ether predominates. The regiochemistry of the adducts derived from monosubstituted acetylenes were determined by the correlation of 13C chemical shifts of the adducts and the corresponding bicyclo[2.2.2]octa-5,7-diene-2,3-diones obtained from the hydrolysis of the spirolactone ring of the Diels-Alder adducts. Photolysis of these α-diketones gave the corresponding aromatic compounds in high yields. These synthetic sequences provide an effective entry to bicyclo[2.2.2]octa-5,7-diene-2,3-diones and polysubstituted benzene derivatives.
TL;DR: The testability condition for single branch-fault of an analog network is given in this article, and several necessary and sufficient conditions for this testability conditions are provided and their proofs are shown in detail.
Abstract: The testability condition for single branch-fault of an analog network is given. Then several necessary and sufficient conditions for this testability condition are provided and their proofs are shown in detail. These conditions have great applications in the testability design as demonstrated in the examples.
TL;DR: The results suggest that the pharmacologically active region of the molecule is different from the micellular substrate binding site but strongly influenced by the invariant histidine-48 located at the enzymatic active site.
TL;DR: The electrical conduction properties of ion implanted polycrystalline silicon films have been studied in this paper, where they were implanted with boron or phosphorus ions, accelerated to 145 keV.
Abstract: The electrical conduction properties of ion implanted polycrystalline silicon films have been studied. The polysilicon films were deposited by pyrolysis of silane at 647°C in LPCVD system onto oxide-coated silicon wafers to a thickness of 0.6 μm. Dopants were itroducd by implanting with boron or phosphorus ions, accelerated to 145 keV; doses ranged from 1 × 10 12 cm −2 to 1 × 10 15 cm −2 . Film resistivities spanning 8 orders of magnitude were obtained using this doping range. Current-voltage characteristics of polysilicon resistors were measured at temperatures ranging from 24 to 140°C. The associated barrier heights and activation energies were derived. The grain-boundary trapping states density was estimated to be 5 × 10 12 cm −2 . We found that both dopant atom segregation and carrier trapping at the grain boundaries play important roles in polysilicon electrical conduction properties. However, within the dose range studies, the dopant atom segragation is most detrimental to the film conductivity for doses 13 cm −2 ; as the dose is increased, carrier trapping effects become more pronounced for doses up to 5 × 10 14 cm −2 . For doses ⩾ 5 × 10 14 cm −2 , conduction due to carriers tunneling through the potential barriers at grain boundaries has to be considered.
TL;DR: In this article, the reduction of CuO with hydrogen has been studied with a temperature programmed reduction technique, the reduction was initiated with a interaction between hydrogen and active sites of copper oxide, the rate of reduction was limited by the diffusion of water from the crystalline.
Abstract: The reduction of CuO with hydrogen has been studied with a temperature programmed reduction technique. According to a proposed reduction mechanism, the reduction was initiated with a interaction between hydrogen and active sites of copper oxide, the rate of the reduction was limited by the diffusion of water from the crystalline. The activation energy of this diffusion is found to be 13Kcal/mol. Reoxidation of copper powder may cause redispersion of the crystalline. The chemical interaction between copper oxide and Cabosil is found very weak.
TL;DR: The testability condition for single branch-fault of an analog network is given in this article, and several necessary and sufficient conditions for this testability conditions are provided and their proofs are shown in detail.
Abstract: The testability condition for single branch-fault of an analog network is given. Then several necessary and sufficient conditions for this testability condition are provided and their proofs are shown in detail. These conditions have great applications in the testability design as demonstrated in the examples.