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1.
一阶形式系统K~*及其完备性 总被引:2,自引:0,他引:2
裴道武 《数学年刊A辑(中文版)》2002,(6)
模糊命题演算的形式系统L*已经在模糊逻辑与模糊推理的结合研究中得到了成功的应用.本文考虑与系统L*相应的一阶逻辑理论,建立了一阶形式系统K*,并证明了这个系统的完备性. 相似文献
2.
本文先从软件理论的角度对安全协议分析语言CPAL的语法和语义进行分析,指出这种语言控制流的缺陷,在语法和语义方面给出CPAL语言的完善方案,并从信息安全中的协议的广泛性方面说明其必要性。 相似文献
3.
4.
We examined the variation with ionic strength (I, adjusted with KCl, KNO3, KBr, NaCl or NaClO4) of the formal potential (Econst) for glass electrodes exhibiting a Nernstian response (i.e. Ecell=Econst−s log [H+]). For this purpose, we investigated the different factors included in the formal potential, so we obtained reported values for the liquid junction potential as a function of ionic strength and determined the logarithm of the activity coefficient for the proton in various saline media, using Pitzer equations. 相似文献
5.
Applying a formal analysis technique to the CCITT X.509 strong two-way authentication protocol 总被引:1,自引:0,他引:1
In the quest for open systems, standardization of security mechanisms, framework, and protocols are becoming increasingly important. This puts high demands on the correctness of the standards. In this paper we use a formal logic-based approach to protocol analysis introduced by Burrows et al. [1]. We extend this logic to deal with protocols using public key cryptography, and with the notion of duration to capture some time-related aspects. The extended logic is used to analyse an important CCITT standard, the X.509 Authentication Framework. We conclude that protocol analysis can benefit from the use of the notation and that it highlights important aspects of the protocol analysed. Some aspects of the formalism need further study.This research was sponsored by the Royal Norwegian Council for Scientific and Industrial Research under Grant IT 0333.22222, and was performed while K. Gaarder was at Alcatel STK Research Centre. 相似文献
6.
Formal methods are becoming favorable for control and verification of safety-critical systems because of the rigorous model-based computation. Relying on an over-approximated model of the original system behaviors, formal control synthesis algorithms are not often complete, which means that a controller cannot necessarily be synthesized even if there exists one. The main result of this paper shows that, for continuous-time nonlinear systems, a sample-and-hold control strategy for a reach-and-stay specification can be synthesized whenever such a strategy exists for the same system with its dynamics perturbed by small disturbances. Control synthesis is carried out by a fixed-point algorithm that adaptively partitions the system state space into a finite number of cells. In each iteration, the reachable set from each cell after one sampling time is over-approximated within a precision determined by the bound of the disturbances. To meet such a requirement, we integrate validated high-order Taylor expansion of the system solution over one sampling period into every fixed-point iteration and provide a criterion for choosing the Taylor order and the partition precision. Two nonlinear system examples are given to illustrate the effectiveness of the proposed method. 相似文献
7.
Maksymilian Ignaczak Andrzej Grzejdziak 《Monatshefte für Chemie / Chemical Monthly》1988,119(1):71-81
Predominance areas of various equilibria were identified and complex formation constants of Ag(I) with 1,10-phenanthroline were determined as well as the solubility product of the complex salt for Ag(phen)2ClO4 in propylene carbonate. The solubility product of AgNO3 in propylene carbonate was estimated. The value of the formal potential of the system Ag(phen)
2
2+
/Ag(phen)
2
+
inPC was determined by chronovoltammetry. Differences in the stability of analogous complexes in water andPC are discussed.
Die Gleichgewichtskonstante der Komplexierung und die Redoxpotentiale im System Ag(II)/Ag(I)-1,10-Phenantrolin in Propylencarbonat
Zusammenfassung Die Gebiete der Dominanz der einzelnen Gleichgewichte, die Bildungskonstanten 1 und 2 der Komplexe Ag(I) mit 1,10-Phenantrolin und der Wert des Löslichkeitsproduktes Ag(phen)2ClO4 in Propylencarbonat wurden bestimmt. Das Löslichkeitsprodukt von AgNO3 in Propylencarbonat wurde abgeschätzt. Die Werte des formalen Potentials des Systems Ag(phen) 2 2+ /Ag(phen) 2 + inPC wurden mit Hilfe cyclischer Voltametrie ermittelt. Es wurden weiterhin die Unterschiede in der Stabilität analoger Komplexe in Wasser und in Propylencarbonat diskutiert.相似文献
8.
Maksymilian Ignaczak Andrzej Grzejdziak Barbara Olejniczak 《Monatshefte für Chemie / Chemical Monthly》1989,120(6-7):515-527
Summary The conditional protonation constants (=0.1) for 2,2:6,2-terpyridine, logK
1=4.93, logK
2=3.69, were determined by thepH-metric method. The compositions of complexes of Ag2+ and Ag+ ions with 2,2:6,2-terpyridine (tp) were studied and equilibria of the complex formation process were described. The values of conditional complex formation constants are as follows: for Ag(tp)
2
+
:log01=5.79, log02=9.68, for Ag(tp)
2
2+
:log02=25.31, while the conditional constant of the Ag(tp)NO3 precipitate formation is:K
SO=2.45·104. Using coulometric and chronovoltamperometric measurements, the redox systems being formed in the complex solutions of Ag(II) and Ag(I) were determined and described including their formal potentials.
Komplexibildungsgleichgewichte und Redoxpotentiale des Systems Ag(II)/Ag(I) in Gegenwart von 2,2:6,2-Terpyridin in Wasser
Zusammenfassung Mit Hilfe derpH-metrischen Methode wurden die konditionalen Protonationskonstanten (=0.1) von 2,2:6,2-Terpyridin bestimmt: logK 1=4.93, logK 2=3.69. Es wurde auch die Zusammensetzung der Komplexe von Ag(II) und Ag(I) mit 2,2:6,2-Terpyridin(tp) bestimmt sowie die Gleichgewichte der komplexbildung beschrieben. Die Werte der Konditionalkomplexbildungskonstanten sind: für Ag(tp) 2 + :log01=5.79, log02=9.68, für Ag(tp) 2 2+ :log02=25.31 und für das Löslichkeitsprodukt Ag(tp)NO3:K SO –1 =4.08·10–5. Die in Komplexlösungen von Ag(II) und Ag(I) vorliegenden Redoxsysteme wurden mittels cyclischer Voltametrie und Coulometrie untersucht und die Formalpotentialwerte dieser Systeme in Wasser bestimmt.相似文献
9.
We consider β-expansions of formal Laurent series over finite fields. If the base β is a Pisot or Salem series, we prove that the β-expansion of a Laurent series α is automatic if and only if α is algebraic. 相似文献
10.
Concise and efficient base-promoted domino formal (3+3) cycloaddition has been established for the formation of tetracyclic indolo[2,3-b]quinoline derivatives under microwave heating. The present methodology shows attractive properties, such as the maximum efficiency of a process, short reaction periods, and operational simplicity, and it can avoid time-consuming and costly syntheses, tedious work-up and isolation of intermediate. This chemistry provides a facile and promising synthetic strategy to construction of tetracyclic indolo[2,3-b]quinoline skeleton. 相似文献