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101.
This paper deals with a design method for an adaptive scheme which would identify the parameters and observe the state of any unknown single-input single-output linear discrete-time systems using only input-output data. Kreisselmeier's parametrized system [5] is used instead of the original system. Then the parameter identification process and the state observation process are well separated. To accelerate the convergence rate of the estimates, a finite-time settling scheme is proposed. It is shown that the estimates obtained converges to true values at k = 3n ?1, where k is the discrete time and n is the order of system. A numerical example is given to indicate acceptable performance of the proposed scheme. 相似文献
102.
Toshiaki Kurokawa 《Software》1978,8(3):277-284
LISP1.9 provides new input/output facilities, the conceptual channel and the current channel, which make program writing easier and execution faster. The channel attributes-column-setting, line number option, prompt-string, user-buffer, eol-handler, eof-handler and access rights-are useful for program writing; the channel interaction attributes-input-memo, output-memo and file I/O verification-are useful for system development. Random file I/O, array I/O, record handling, array-string conversion and Japanese character output are also provided. 相似文献
103.
The effect of the IVa element addition to the niobium core and that of gallium addition to the matrix on the composition, growth rate and superconducting properties of the composite-processed Nb3Sn have been studied. The IVa elements added to the niobium core enhance the growth rate of Nb3Sn, and prevent the grain coarsening of Nb3Sn. A much larger amount of titanium is incorporated into Nb3Sn than zirconium or hafnium. Tc shows a slight maximum against the IVa element concentration in the niobium core. Jc at high magnetic fields is more significantly increased by titanium addition than zirconium or hafnium additions. The gallium substitution for tin in the matrix is effective for increasing Tc and Jc in high fields, except for the specimen with Nb-Ti alloy core. The simultaneous addition of hafnium and gallium is most effective for the enhancement of Jc in high fields. 相似文献
104.
Computed tomography (CT) is increasingly employed in orthodontic treatment. One of the most successful applications is in dental implantology, in which an artificial root is surgically inserted into the jawbone to provide anchorage for a dental prosthesis. For successful implant surgery, it is crucial to locate internal structures such as the inferior alveolar nerve canal (IAC). This paper presents a computerized technique for extracting the IAC. To facilitate the extraction, we first generate panoramic CT images (panoramics) by reformatting the original CT images. The panoramics are a series of cross-sectional images along curved planes through the mandible (lower jawbone). Hollow canals are subsequently detected by analyzing the voxel intensities and 3-D gradient orientations in the panoramics. The axis of the IAC is then traced out by a novel 3-D line-tracking technique. The method is effective for extracting the IAC despite the open structure of the surrounding bone. 相似文献
105.
106.
A series of oligomeric viologens were synthesized in order to investigate the polymer effect in electrochromic behavior of viologen compounds. These materials have a lower first-step reduction potential and a higher second-step reduction potential compared with monomeric viologens. As a result, they have wider potential separation, where stable viologene radical salts are produced. Spectroscopic analysis suggests that stable monomeric viologen radical salts do not exist in water, but there is some intramolecular interaction between viologen radicals of the oligomers. This intramolecular interaction is responsible for the reduction behavior and the stability of radical films of oligomeric viologens. 相似文献
107.
Alpha-glucosidase, a key enzyme for nuka-sake brewing, was purified from Oryza sativa cv. Yamadanishiki, which is widely used for sake brewing. The molecular weight of the purified enzyme was 95 kDa. The optimum pH and temperature were 4.5 and 55 degrees C, respectively. The substrate specificity differed from that of Oryza sativa cv. Shinsetsu, which is a variety of rice consumed as a cereal. The extraction of alpha-glucosidase from the rice was stimulated by lactic acid, which suggests that lactic acid plays an important role not only in preventing bacterial contamination, but also in stimulating the parallel fermentation that occurs in nuka-sake brewing. 相似文献
108.
Yosuke Kimura Masaharu Asano Ryoichi Katakai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(2):463-467
Poly(ethylene-co-tetrafluoroethylene) (ETFE) films were irradiated by swift heavy ion-beams of 129Xe23+ with fluences of 0, 3 × 106, 3 × 107, 3 × 108 and 3 × 109 ions/cm2, followed by γ-ray pre-irradiation for radiation grafting of styrene onto the ETFE films and sulfonation of the grafted ETFE films to prepare highly anisotropic proton-conducting membranes. The fluence of Xe ions and the addition of water in the grafting solvent were examined to determine their effect on the proton conductivity of the resultant membranes. It was found that the polymer electrolyte membrane prepared by grafting the styrene monomer in a mixture of 67% isopropanol and 33% water to the ETFE film with an ion-beam irradiation fluence of 3.0 × 106 ions/cm2 was a highly anisotropic proton-conducting material, as the proton conductivity was three or more times higher in the thickness direction than in the surface direction of the membrane. 相似文献
109.
Exact Analysis of a One-Dimensional Attractive δ-Function Fermi Gas with Arbitrary Spin Polarization
We study a one-dimensional integrable system of N spin-1/2 fermions with attractive δ-function interaction at zero temperature. The Gaudin integral equation describing the ground state with arbitrary spin polarization
is solved in the form of power series. We also study the ground state energy as a function of the coupling constant and the
polarization. 相似文献
110.
Toshiaki Kobayashi Junko Taniguchi Masaru Suzuki Keiya Shirahama 《Journal of Low Temperature Physics》2007,148(5-6):797-801
Previously, we carried out ultrasonic measurements for liquid 4He filled in a nanoporous glass (Gelsil), and observed an increase in the sound velocity due to decoupling of the superfluid
component. At zero pressure, the superfluid transition temperature T
C is suppressed to 1.4 K from the bulk lambda point, 2.17 K. This behavior is the same as torsional oscillator measurements
by Yamamoto et al. (Phys. Rev. Lett. 93:075302, 2004). However, the pressure dependence of T
C and the temperature dependence of the superfluid fraction are very different from the torsional oscillator measurements.
In order to clarify the origin of the difference, we have developed a new technique of simultaneous measurement of an ultrasound
and a torsional oscillator, and the system successfully works for a nanoporous glass. Here, we compare decoupling of the superfluid
component for 4He films between an ultrasound and a torsional oscillator. 相似文献