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11.
This paper proposes a two step algorithm for solving a large scale semi-definite logit model, which is appreciated as a powerful
model in failure discriminant analysis. This problem has been successfully solved by a cutting plane (outer approximation)
algorithm. However, it requires much more computation time than the corresponding linear logit model. A two step algorithm
to be proposed in this paper is intended to reduce the amount of computation time by eliminating a certain portion of the
data based on the information obtained by solving an associated linear logit model. It will be shown that this algorithm can
generate a solution with almost the same quality as the solution obtained by solving the original large scale semi-definite
model within a fraction of computation time. 相似文献
12.
H. Wada T. Kamijoh 《Photonics Technology Letters, IEEE》1996,8(2):173-175
1.3-/spl mu/m InGaAsP-InP lasers have been successfully fabricated on Si substrates by wafer bonding with heat treatment at 400/spl deg/C. A pressure of 4 kg/cm/sup 2/ has been applied on the wafers before the heat treatment and this pressure application has enabled us to achieve bonding strength required for the device fabrication even when the bonding temperature is as low as 400/spl deg/C. Room-temperature continuous-wave operation with threshold current of 49 mA has been achieved for 7-/spl mu/m-wide mesa lasers. 相似文献
13.
Popovic M. Wada K. Akiyama S. Haus H.A. Michel J. 《Lightwave Technology, Journal of》2002,20(9):1762-1772
Air trench structures for reduced-size bends in low-index contrast waveguides are proposed. To minimize junction loss, the structures are designed to provide adiabatic mode shaping between low- and high-index contrast regions, which is achieved by the introduction of "cladding tapers." Drastic reduction in effective bend radius is predicted. We present two-dimensional (2-D) finite-difference time-domain/effective index method simulations of bends in representative silica index contrasts. We also argue that substrate loss, while present, can be controlled with such air trenches and reduced to arbitrarily low levels limited only by fabrication capabilities. The required trench depth, given an acceptable substrate loss, is calculated in three dimensions using an approximate equivalent current sheet method and also by a numerical solver for full-vector leaky modes. A simple, compact waveguide T-splitter using air trench bends is presented. 相似文献
14.
H. Ebe T. Okamoto H. Nishino T. Saito Y. Nishijima M. Uchikoshi M. Nagashima H. Wada 《Journal of Electronic Materials》1996,25(8):1358-1361
CdTe epilayers were grown directly on (100), (211), and (111) silicon substrates by metalorganic chemical vapor deposition
(MOCVD). The crystallinity and the growth orientation of the CdTe film were dependent on the surface treatment of the Si substrate.
The surface treatment consisted of exposure of the Si surface to diethyltelluride (DETe) at temperatures over 600°C prior
to CdTe growth. Direct growth of CdTe on (100) Si produced polycrystalline films whereas (lll)B single crystals grew when
Si was exposed to DETe prior to CdTe growth. On (211) Si, single crystal films with (133)A orientation was obtained when grown
directly; but produced films with (211)A orientation when the Si surface was exposed to DETe. On the other hand, only (lll)A
CdTe films were possible on (111) Si, both with and without Te source exposure, although twinning was increased after exposure.
The results indicate that the exposure to a Te-source changes the initial growth stage significantly, except for the growth
on (111) Si. We propose a model in which a Te atom replaces a Si atom that is bound to two Si atoms. 相似文献
15.
Initial reactions of the metabolic processes in bacterial cells have been investigated by measuring heat generation of under nongrowing conditions with a titrimetric calorimeter. Three exothermic reactions with different rates of heat generation have been observed calorimetrically under aerobic condition when glucose solution was added to the cell suspension of nongrowing medium. It was estimated that the first exothermic peak obtained after adding glucose was due to uptaking of substrate molecules and following two peaks reflected to the reaction of phosphofructokinase and that of glyceraldehyde-3-phosphate dehydrogenase respectively. To clarify the process of glycolysis, measurements of heat evolution due to metabolisms of various sugars except glucose have also examined and compared with that of glucose. 相似文献
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18.
Naoya Inazumi Shunzo Yamamoto Yoshimi Sueishi 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):33-39
The inclusion complexation of p-sulfonatocalix[6]arene (Calix-S6) with three kinds of phenothiazine dyes was studied spectrophotometrically in a mixture
of a room-temperature ionic liquid [bmim]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) and ethanol. We have determined the association constants of Calix-S6 with
phenothiazine dyes under external static pressure up to 767 bar in the [bmim]BF4-ethanol and alcohol-water mixtures. With increasing external pressure, the inclusion equilibrium in the alcohol-water mixtures
was shifted to the dissociation side. Conversely, the inclusion equilibrium of methylene blue (MB) and azure A (AA) in the
ionic liquid mixture was shifted to the association side. From the analysis of the pressure effects, the reaction volumes
ΔV for inclusion complexation were estimated as −7 to 9 cm3 mol−1 in the [bmim]BF4-ethanol mixture and 20–32 cm3 mol−1 in the alcohol-water mixtures. Based on the results, we have suggested that there is a competing complexation between the
included dye and [bmim]BF4 molecules in the ionic liquid. 相似文献
19.