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1.
Alex Hellsten 《Archive for Mathematical Logic》2006,45(6):705-714
We extract some properties of Mahlo’s operation and show that some other very natural operations share these properties. The weakly compact sets form a similar hierarchy as the stationary sets. The height of this hierarchy is a large cardinal property connected to saturation properties of the weakly compact ideal. 相似文献
2.
This note investigates two long-standing conjectures on the Krull dimension of integer-valued polynomial rings and of polynomial rings in the context of (locally) essential domains.
3.
THE FIRST EXPERIMENT OF A THz GYROTRON WITH A PULSE MAGNET 总被引:1,自引:0,他引:1
T. Idehara H. Tsuchiya O. Watanabe La Agusu S. Mitsudo 《International Journal of Infrared and Millimeter Waves》2006,27(3):319-331
A THz gyrotron with a pulse magnet has been designed, constructed and operated in FIR FU. It is developed as one of high frequency
gyrotrons included in Gyrotron FU Series. The gyrotron has already achieved the first experimental result for high frequency
operations whose radiation frequency exceeds 1 THz. In this paper, the design detail and the operation test results for sub-terahertz
to terahertz range are described. The second harmonic operation is confirmed experimentally at the expected frequency of 1.005
THz due to TE6,11 cavity mode at the magnetic field intensity of 19.0 T. 相似文献
4.
使用参数Dioid模块网络法,把含大量摄动参数的在普通极大代数意义下非线性状态空间模型在参数Dioid意义下线性化,在此基础上研究一类过程摄动系统的无阻塞鲁棒性.给出了有限缓冲串行生产系统在没有缓冲器下无阻塞的充要条件和充分条件. 相似文献
5.
Tjalling J. Ypma 《Numerical Linear Algebra with Applications》1995,2(6):533-541
An algorithm for pre- or post-multiplication of a matrix by a plane rotation, using only three vector saxpy operations instead of the four vector operations usually considered necessary, is described. No auxiliary storage for overwriting is required. The method is shown to be numerically stable. 相似文献
6.
M. Markl 《Czechoslovak Mathematical Journal》2007,57(1):473-503
The aim of this note, which raises more questions than it answers, is to study natural operations acting on the cohomology
of various types of algebras. It contains a lot of very surprising partial results and examples. 相似文献
7.
Victor Snaith 《K-Theory》1991,5(3):265-279
Let G be a finite group. The class group of the group ring of G is a quotient of the idèlic homomorphisms of R(G) by the global functions and the determinantal functions. Using Explicit Brauer Induction, we prove Adams operations, applied to determinantal functions, satisfy some congruences which were conjectured by M. J. Taylor. As an application, we construct some new maps defined on the class group.In memory of J. Frank Adams (1930–1989)Research partially supported by NSERC Grant # 0GP0042580. 相似文献
8.
A. A. Bulatov 《Algebra and Logic》2006,45(6):371-388
A combinatorial constraint satisfaction problem aims at expressing in unified terms a wide spectrum of problems in various
branches of mathematics, computer science, and AI. The generalized satisfiability problem is NP-complete, but many of its
restricted versions can be solved in a polynomial time. It is known that the computational complexity of a restricted constraint
satisfaction problem depends only on a set of polymorphisms of relations which are admitted to be used in the problem. For
the case where a set of such relations is invariant under some Mal’tsev operation, we show that the corresponding constraint
satisfaction problem can be solved in a polynomial time.
__________
Translated from Algebra i Logika, Vol. 45, No. 6, pp. 655–686, November–December, 2006. 相似文献
9.
Hongyu Liu Xinhui Guo Juncheng Chen Aobo Song Gu Jin Qizhi Yao Jiao Li Lingling Li 《大学化学》1986,35(12):221-226
This paper introduces an experiment about waste liquid recovery and effect evaluation in laboratory. Through this experiment, the basic operations of crystal preparation, chemical analysis and instrumental analysis are further consolidated. At the same time, it allows students to experience a series of possible problems of condition selection and control in the process of waste liquid treatment. We hope to improve the students' ability to analyze and solve problems, enhance their interest in learning, and strengthen their humanistic education. 相似文献
10.
In our former investigations, the phenomenon high temperature corrosion (HTC) was described exemplarily on selected materialcoating combinations for blades of stationary gas turbines, mainly in the temperature region of up to 750° C. To answer the question, in which manner higher gas inlet and/or higher material surface temperature would influence the HTC behaviour, a special analytical technique—the integral layer profile analysis—was introduced to ameliorate concentration profile methods. By examining IN 738 LC specimens with CoCrAlY plasma spray coating, stressed by hot gas at 900° C, the limits of this system are shown by explaining the corrosion mechanism; the method is also used for other systems, e.g. U 520 with NiCrAlY coating at 750° C. 相似文献