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21.
We first note that Gentzen's proof-reduction for his consistency proof of PA can be directly interpreted as moves of Kirby-Paris' Hydra Game, which implies a direct independence proof of the game (Section 1 and Appendix). Buchholz's Hydra Game for labeled hydras is known to be much stronger than PA. However, we show that the one-dimensional version of Buchholz's Game can be exactly identified to Kirby-Paris' Game (which is two-dimensional but without labels), by a simple and natural interpretation (Section 2). Jervell proposed another type of a combinatorial game, by abstracting Gentzen's proof-reductions and showed that his game is independent of PA. We show (Section 3) that this Jervell's game is actually much stronger than PA, by showing that the critical ordinal of Jervell's game is φω (0) (while that of PA or of Kirby-Paris' Game is φ1 (0) = ?0) in the Veblen hierarchy of ordinals. 相似文献
22.
Monolithic rat-race mixers for millimeter waves 总被引:1,自引:0,他引:1
Matsuura H. Tezuka K. Aoki I. Yamanaka M. Kobayashi S. Fujita T. Miura A. 《Microwave Theory and Techniques》1998,46(6):839-841
In this paper, we report on fully monolithic millimeter-wave Schottky-barrier diode (SBD) down-converters with an IF amplifier using heterojunction bipolar transistors (HBT's). A rat-race circuit is used for the mixer, and is analyzed using a harmonic-balance simulator. The measured conversion gain and the isolation are 7.1 and 29 dB in the V-band design, and 8.0 and 25 dB in the W-band design, respectively. The conversion gains are matched well with the circuit simulation 相似文献
23.
Masahiro Kubo 《Journal of Mathematical Analysis and Applications》2005,307(1):232-244
We study Neumann problem for a class of nonlinear degenerate parabolic PDE. A typical nonlinearity we have in mind is, for instance, β(u)=−1/u(u>0). We establish a necessary and sufficient condition on given data for existence of solution. 相似文献
24.
Comparison of the effect of a proteolytic enzyme dispase and a chelator for the preparation of epidermal sheet from nude mice. 总被引:1,自引:0,他引:1
Histochemical studies of epidermal Langerhans cells require well-preserved epidermal sheets. We studied the conditions for the preparation of the epidermal sheets from the skin of the ear, hind limb and trunk of nude mice. Two types of commercial dispase, and ethylenediaminetetraacetic acid (EDTA), were used at several concentrations and the effects were compared. Dermo-epidermal separation was evaluated by the preservation of ATPase activity of Langerhans cells in the epidermal sheet and by the ultrastructure of epidermal cells (Langerhans cells and keratinocytes) as well as epidermal-dermal junction. Good separation depended on the combination of the concentration of the reagent and site of the skin. The concentrations of both dispase and EDTA effective for separation of the epidermis in the nude mouse were lower than those in other mouse strains reported. 相似文献
25.
Ciguatoxin C-CTX-1 was isolated as a principal causative toxin of ciguatera seafood poisoning in the Caribbean Sea, and is structurally classified as a ladder-shaped polycyclic ether. In this Letter, we report the synthesis of the tricyclic LMN-ring system of C-CTX-1. SmI2-mediated reductive cyclization efficiently constructed the seven-membered M-ring with the axially oriented 1,3-dimethyl structure. 相似文献
26.
27.
28.
Chapuis Y-A. Lingfei Zhou Fukuta Y. Mita Y. Fujita H. 《Industrial Electronics, IEEE Transactions on》2007,54(4):1926-1936
In this paper, the authors have developed and implemented a decentralized decision-making strategy using field-programmable gate array (FPGA) technology as a prototype for an integrated controller of a microelectromechanical systems (MEMS) array for air-flow planar micromanipulation. The MEMS array was proposed to be integrated in a hybrid multichip module containing the FPGA-based controller. Algorithms and architectures, used for the decentralized control implementation and the hardware resource optimization, are described. A charge-coupled device camera was used to make each MEMS like an autonomous system when the distributed MEMS chip was tested. Finally, under air-flow condition, the FPGA-based decentralized control system successfully performed an object manipulation. 相似文献
29.
Masahiro Nakao Chikako Yamazaki Hiroshi Tominaga Takako Yamaguchi Yoshikazu Fujita 《Analytical sciences》2006,22(2):313-316
A simple and highly sensitive spectrophotometric method for the determination of anthracycline anticancer agents, such as Daunorubicin hydrochloride (DAU), was established by using aluminum(III) and Chromazurol S (CAS) in a nonionic surfactant micellar medium. In the case of determination of DAU, the apparent molar absorptivity was 1.3 x 10(5) dm3 mol(-1) cm(-1) at 615 nm. Beer's law was obeyed in the concentration range of 0.028 - 2.82 microg ml(-1) for DAU. Owing to no need for solvent extraction, this method could be applied to assays of DAU and related drugs in pharmaceutical preparations. 相似文献
30.
The microstructure of InxGa1−xAs/GaAs (5 nm/5 nm, x < 0 to 1.0), as grown by a metalorganic chemical vapor deposition two-step growth technique on Si(100)
at 450‡C, and subsequently annealed at 750‡C, is investigated using plan-view and cross-sectional transmission electron microscopy.
The variations in resultant island morphology and strain as a function of the In content were examined through the comparison
of the misfit dislocation arrays and moirés observed. The results are discussed in relation to the ways in which the island
relaxation process changes for high In content. 相似文献