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1.
C. Cooper R. Gilchrist I. N. Kovalenko D. Novakovic 《Cybernetics and Systems Analysis》1999,35(5):688-693
The authors propose two methods of estimating the number of so-called “good” permutations, which are defined in the article.
The nature of both methods is statistical, but their methodologies are completely different. The use of these methods is illustrated
by the example of the permutation length N = 25, which is of intense interest in cryptography.
Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 10–16, September–October, 1999. 相似文献
2.
V. G. Il'ichev 《Cybernetics and Systems Analysis》1995,31(6):869-877
Conclusion In the models of passive-state formation considered above we have assumed for simplicity constant control parameters. In reality,
the control parameters are functions of time, environmental factors, and the values of the “active” variables [7, 8]. These
functions are “reasonably” constructed: under “bad” conditions the variables shift to a passive state, and when “good” conditions
are restored, the variables switch back to active state.
It is relevant to develop and analyze the corresponding model circuits. Here we can expect to observe even stronger stabilization
effects in the behavior of complex systems.
In conclusion, I would like to thank an anonymous referee for useful comments.
The study is financed by the Russian Foundation of Basic Research.
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 103–112, November–December, 1995. 相似文献
3.
In certain situations the state of a quantum system, after transmission through a quantum channel, can be perfectly restored.
This can be done by “coding” the state space of the system before transmission into a “protected” part of a larger state space,
and by applying a proper “decoding” map afterwards. By a version of the Heisenberg Principle, which we prove, such a protected
space must be “dark” in the sense that no information leaks out during the transmission. We explain the role of the Knill–Laflamme
condition in relation to protection and darkness, and we analyze several degrees of protection, whether related to error correction,
or to state restauration after a measurement. Recent results on higher rank numerical ranges of operators are used to construct
examples. In particular, dark spaces are constructed for any map of rank 2, for a biased permutations channel and for certain
separable maps acting on multipartite systems. Furthermore, error correction subspaces are provided for a class of tri-unitary
noise models. 相似文献
4.
Giuseppe Di Battista Fabrizio Frati Maurizio Patrignani 《Theory of Computing Systems》2009,44(2):143-159
Graph Drawing is (usually) concerned with the production of readable representations of graphs. In this paper, instead of
investigating how to produce “good” drawings we tackle the opposite problem of producing “bad” drawings. In particular, we
study how to construct orthogonal drawings with many bends along the edges and with large area. Our results show surprising
contact points, in Graph Drawing, between the computational cost of niceness and the one of ugliness. 相似文献
5.
The paper deals with a new method of solving a combinatorial problem with account for the properties of the set of permutations
and its structure. Using this method, the values of the linear objective function are sequenced and the set of permutations
is decomposed over hyperplanes, with account of element recurrences. This makes it possible to develop an algorithm of finding
the point (an element of the set of permutations) at which the objective function attains a given value.
Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 50–61, March–April 2009. 相似文献
6.
Alessandra Capanna 《Nexus Network Journal》2009,11(2):257-271
This paper is one of a set of lessons prepared for the course of “Theory of Architecture” (Faculty of Architecture – “La Sapienza”
University of Rome). The didactic aim was to present – to students attending the first year of courses – some methods for
the beginning stages of design and their applicability to any kind creative work. The brief multimedia hypertext quoted at
the end of this paper was carried out in collaboration with the “LaMA” (Laboratorio Multimediale di Architettura) as a test
for new educational tools applied to first our “e-learning” experiences. 相似文献
7.
N. Yu. Kuznetsov 《Cybernetics and Systems Analysis》2007,43(6):830-837
A permutation (s0, s1,…, sN − 1) of symbols 0, 1,…, N − 1, is called good if the set (t0, t1,…, tN − 1) formed according to the rule ti = i + si (mod N), i = 0, 1, … N − 1, is also a permutation. A fast simulation method is proposed. It allows the number of good permutations
to be evaluated with high accuracy for large N (in particular, N > 100). Empirical upper and lower bounds for the number of
good permutations are presented and verified against numerical data.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 80–89, November–December 2007. 相似文献
8.
Systems of induced generating actions of automaton permutations groups on words of length r are investigated. A family of
irreducible systems of generators is constructed, and the cardinality of such systems is found to be related with r. The infinite
generativity (even in the topological sense) of groups of all automaton permutations, finite automaton permutations, and finitary
automaton permutations is established; the well-known proof of this fact contained an error.
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 121–133, May–June, 2000. 相似文献
9.
N. Yu. Kuznetsov 《Cybernetics and Systems Analysis》2008,44(4):547-554
A permutation (s0, s1,…, sN − 1) of symbols 0, 1,…, N − 1 s called good if the set (t0, t1,…, tN − 1) formed according to the rule ti = i + si (mod N), i = 0, 1,…, N − 1, is a permutation too. A modified fast simulation method is proposed to evaluate the number of good
permutations for N = 205 with a 5% relative error. Empirical upper and lower bounds for the number of good permutations are
also given.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 101–109, July–August 2008. 相似文献
10.
11.
About the Collatz conjecture 总被引:1,自引:0,他引:1
This paper refers to the Collatz conjecture. The origin and the formalization of the Collatz problem are presented in the
first section, named “Introduction”. In the second section, entitled “Properties of the Collatz function”, we treat mainly
the bijectivity of the Collatz function. Using the obtained results, we construct a (set of) binary tree(s) which “simulate(s)”–
in a way that will be specified – the computations of the values of the Collatz function. In the third section, we give an
“efficient” algorithm for computing the number of iterations (recursive calls) of the Collatz function. A comparison between
our algorithm and the standard one is also presented, the first being at least 2.25 “faster” (3.00 in medium). Finally, we
describe a class of natural numbers for which the conjecture is true.
Received 28 April 1997 / 10 June 1997 相似文献
12.
13.
Thomas Kühne 《Software and Systems Modeling》2006,5(4):369-385
With the recent trend to model driven engineering a common understanding of basic notions such as “model” and “metamodel” becomes a pivotal issue. Even though these notions have been in widespread use for quite a while, there is still little consensus about when exactly it is appropriate to use them. The aim of this article is to start establishing a consensus about generally acceptable terminology. Its main contributions are the distinction between two fundamentally different kinds of model roles, i.e. “token model” versus “type model” (The terms “type” and “token” have been introduced by C.S. Peirce, 1839–1914.), a formal notion of “metaness”, and the consideration of “generalization” as yet another basic relationship between models. In particular, the recognition of the fundamental difference between the above mentioned two kinds of model roles is crucial in order to enable communication among the model driven engineering community that is free of both unnoticed
misunderstandings and unnecessary disagreement. 相似文献
14.
Information assimilation framework for event detection in multimedia surveillance systems 总被引:1,自引:0,他引:1
Most multimedia surveillance and monitoring systems nowadays utilize multiple types of sensors to detect events of interest as and when they occur in the environment. However, due to the asynchrony among and diversity of sensors, information assimilation – how to combine the information obtained from asynchronous and multifarious sources is an important and challenging research problem. In this paper, we propose a framework for information assimilation that addresses the issues – “when”, “what” and “how” to assimilate the information obtained from different media sources in order to detect events in multimedia surveillance systems. The proposed framework adopts a hierarchical probabilistic assimilation approach to detect atomic and compound events. To detect an event, our framework uses not only the media streams available at the current instant but it also utilizes their two important properties – first, accumulated past history of whether they have been providing concurring or contradictory evidences, and – second, the system designer’s confidence in them. The experimental results show the utility of the proposed framework. 相似文献
15.
This paper proposes a comprehensive approach to the development of technology infrastructure for the application of information
techology (IT) based solutions in teleconstruction—the performance of on-site construction and related tasks through the use
of IT and robotics by a remotely located team of project participants: general contractor, subcontractors, equipment operators,
materials suppliers, and project office professionals. The paper proposes that technologies exist that enable both terrestrial
and extraterrestrial teleconstruction.
Thomas Bock: German-American “Frontiers of Engineering” Symposium Participant, Essen 2001, Alexander von Humboldt Foundation 2004 “CONNECT”
Award Recipient
Mirosław Skibniewski: German-American “Frontiers of Engineering” Symposium Participant and Member of the Organizing Committee, Essen 2001, Alexander
von Humboldt Foundation 2004 “CONNECT” Award Recipient
2–6: Photos copyright, Thomas Bock, TU Munich, Germany.
7–8: Photos and figure copyright, Prof. Masahiru Nohmi, Kagawa University, Japan. 相似文献
16.
B. Tuffin 《Computing》1998,61(4):371-378
Quasi-Monte Carlo methods and lattice rules with good lattice points give rapidly “good” approximations for numerical integration,
but the error estimation is intractable in practice. In the literature, a randomization of these methods, using a combination
of Monte Carlo and quasi-Monte Carlo methods, has been done to obtain a confidence interval using the Central Limit Theorem.
In this paper we show that for a special class of functions with small Fourier coefficients and using good lattice points,
the decreasing of the variance of the combined estimator is faster than the usual one. 相似文献
17.
Jin-Ho Park interprets Schindler’s “reference frames in space” as set forth in his 1916 lecture note on mathematics, proportion,
and architecture, in the context of Robinson’s1898–99 articles in the Architectural Record. Schindler’s unpublished, handwritten notes provide a source for his concern for “rhythmic” dimensioning in architecture.
He uses a system in which rectangular dimensions are arranged in “rows.” Architectural examples of Schindler’s Shampay, Braxton-Shore
and How Houses illustrate the principles. 相似文献
18.
The capability-based distributed layout approach was first proposed by Baykasoğlu (Int J Prod Res 41, 2597–2618, 2003) for
job shops which are working under highly volatile manufacturing environments in order to avoid high reconfiguration costs.
It was argued that the capability-based distributed layout can also be a valid (or better) option for “classical functional
layouts” which are generally operating under “high variety” and “low-stable demand”. In this paper first the capability-based
distributed layout approach and related issues are reviewed and discussed afterwards the performance of “Capability Based
Distributed Layout: (CB-DL)” is tested via extensive simulation experiments. After the simulation experiments, it is observed
that capability-based distributed layout has a big potential and can also be considered as an alternative to classical process
types of layouts. 相似文献
19.
Afrodita Iorgulescu 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(9):835-856
Since all the algebras connected to logic have, more or less explicitly, an associated order relation, it follows, by duality
principle, that they have two presentations, dual to each other. We classify these dual presentations in “left” and “right”
ones and we consider that, when dealing with several algebras in the same research, it is useful to present them unitarily,
either as “left” algebras or as “right” algebras. In some circumstances, this choice is essential, for instance if we want
to build the ordinal sum (product) between a BL algebra and an MV algebra. We have chosen the “left” presentation and several
algebras of logic have been redefined as particular cases of BCK algebras. We introduce several new properties of algebras
of logic, besides those usually existing in the literature, which generate a more refined classification, depending on the
properties satisfied. In this work (Parts I–V) we make an exhaustive study of these algebras—with two bounds and with one
bound—and we present classes of finite examples, in bounded case. In Part II, we continue to present new properties, and consequently
new algebras; among them, bounded α γ algebra is a common generalization of MTL algebra and divisible bounded residuated lattice
(bounded commutative Rl-monoid). We introduce and study the ordinal sum (product) of two bounded BCK algebras.
Dedicated to Grigore C. Moisil (1906–1973). 相似文献
20.
This paper presents an empirical study for extending the ecological safety model developed for individual activity (Amalberti
in La conduite des systèmes à risques, PUF, 1996; Hoc and Amalberti in J Cogn Eng Decis Mak 1:22–55, 2007) to collective management.
The study took place in a medical emergency center (SAMU) and focused on individual contribution to safety of collective management.
The experiment aimed at extending the domain of validity of the conclusions of a previous study (Marc and Amalberti in Trav
Hum 65:217–242, 2002) showing that individual intervention (as an actor and as an observer) in collective action was a matter
of ecological safety. A “pseudo-simulation” was designed for confronting experienced PARMs and physicians of the SAMU with
a series of “safety events” in the functioning of “their” emergency center. In the position of observers, participants were
asked to comment on what they observed during a series of short periods of simulated activity and to assess situation mastery
by the various actors observed. The results confirm that the model of ecological safety is directly relevant for collective
management of “technical errors”: as observers, participants reacted to safety events depending on their potential consequences;
not all “erroneous” actions oriented toward task performing were detected, and if detected they were not always identified;
participants focused mainly on errors they observed which might have operational consequences on the global quality of safety
management in the center. Concerning “non-technical errors” in collective work, participants were focusing on safety management
by the physician as the responsible for the center safe functioning; they were less prone to identify safety events related
to teamwork itself. These last results can be interpreted at the light of an extension of the ecological model of safety management
for taking into account the teamwork-oriented dimension in collective work. 相似文献