We prove that for any given R between 0 and 1 the best threshold value for a regular LDPC code of rate R with common variable degree v and common check degree c occurs when v is at least 3 and is minimal subject to th...
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We prove that for any given R between 0 and 1 the best threshold value for a regular LDPC code of rate R with common variable degree v and common check degree c occurs when v is at least 3 and is minimal subject to the condition R = 1 - v/c.
This paper is a survey of research of my colleagues and myself aimed at developing a comprehensive logical framework for the verification of real-time distributed systems. The framework is based on predicate logics wi...
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This paper is a survey of research of my colleagues and myself aimed at developing a comprehensive logical framework for the verification of real-time distributed systems. The framework is based on predicate logics with explicit time. To choose such a logic we pursue two goals: first, to make formalization of verification problems rather direct, without unjustified simplifications, and second, to have a logic which permits to describe decidable classes of the verifications problem covering the particular problems we are interested in. Notice that our intention is not to introduce new specification languages, but work directly with those of the user. In this paper we describe First Order Timed Logic (FOTL) that is sufficient to express the main part of verification of systems without uncertainty. The time is continuous (the formalism work as well for discrete time - in our context this case is less interesting and less efficient from algorithmic viewpoint). We give examples of problems that can be treated, describe how to represent runs of programs in FOTL, introduce decidable classes, discuss aspects of practical efficiency. We conclude with open questions.
We present a formulae-as-types interpretation of Subtractive Logic (i.e. bi-intuitionistic logic). This presentation is two-fold: we first define a very natural restriction of the lambdamu-calculus which is closed und...
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We present a formulae-as-types interpretation of Subtractive Logic (i.e. bi-intuitionistic logic). This presentation is two-fold: we first define a very natural restriction of the lambdamu-calculus which is closed under reduction and whose type system is a constructive restriction of the Classical Natural Deduction. Then we extend this deduction system conservatively to Subtractive Logic. From a computational standpoint, the resulting calculus provides a type system for first-class coroutines (a restricted form of first-class continuations).
作者：
Lohou, CBertrand, GESIEE
Lab Algorithm & Architecture Syst Informat F-93162 Noisy Le Grand France
In this paper, we propose a new methodology to conceive a thinning scheme based on the parallel deletion of P-simple points. This scheme needs neither a preliminary labelling nor an extended neighborhood, in the oppos...
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In this paper, we propose a new methodology to conceive a thinning scheme based on the parallel deletion of P-simple points. This scheme needs neither a preliminary labelling nor an extended neighborhood, in the opposite of the already proposed thinning algorithms based on P-simple points. Moreover, from an existent thinning algorithm A, we construct another thinning algorithm A', such that A' deletes at least all the points removed by A, while preserving the same end points. In fact, we propose a 12-subiteration thinning algorithm which deletes at least the points removed by the one proposed by Palagyi and Kuba (Graphical Models Image Process. 61 (1999) 199). (C) 2003 Elsevier B.V. All rights reserved.
We present a formulae-as-types interpretation of Subtractive Logic (i.e. bi-intuitionistic logic). This presentation is two-fold: we first define a very natural restriction of the lambdamu-calculus which is closed und...
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We present a formulae-as-types interpretation of Subtractive Logic (i.e. bi-intuitionistic logic). This presentation is two-fold: we first define a very natural restriction of the lambdamu-calculus which is closed under reduction and whose type system is a constructive restriction of the Classical Natural Deduction. Then we extend this deduction system conservatively to Subtractive Logic. From a computational standpoint, the resulting calculus provides a type system for first-class coroutines (a restricted form of first-class continuations).
The paper presents a verification of the IEEE Root Contention Protocol as an illustration of a new and innovative approach for the verification of real-time distributed systems. Systems are modeled with basic Gurevich...
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ISBN:
(纸本)354021299X
The paper presents a verification of the IEEE Root Contention Protocol as an illustration of a new and innovative approach for the verification of real-time distributed systems. Systems are modeled with basic Gurevich abstract state machines (ASMs), and requirements are expressed in a first order timed logic (FOTL). FOTL is undecidable, however the protocol we study is in a decidable class of practical interest. Advantages of this framework are twofold: on the one hand, a great expressive power which permits in particular an easy treatment of parameters, on the other hand the modeling task is simplified by an adequat choice of tools.
作者：
Lohou, CBertrand, GESIEE
Lab Algorithm & Architecture Syst Informat F-93162 Noisy Le Grand France
In this paper, we propose a new methodology to conceive a thinning scheme based on the parallel deletion of P-simple points. This scheme needs neither a preliminary labelling nor an extended neighborhood, in the oppos...
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In this paper, we propose a new methodology to conceive a thinning scheme based on the parallel deletion of P-simple points. This scheme needs neither a preliminary labelling nor an extended neighborhood, in the opposite of the already proposed thinning algorithms based on P-simple points. Moreover, from an existent thinning algorithm A, we construct another thinning algorithm A', such that A' deletes at least all the points removed by A, while preserving the same end points. In fact, we propose a 12-subiteration thinning algorithm which deletes at least the points removed by the one proposed by Palagyi and Kuba (Graphical Models Image Process. 61 (1999) 199). (C) 2003 Elsevier B.V. All rights reserved.
By means of the so-called optimization of correlation weights of local invariants (OCWLI) in labeled hydrogen-filled graphs (LHFGs) models of toxicity for 33 aldehydes were constructed. The toxicity endpoint was Tetra...
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By means of the so-called optimization of correlation weights of local invariants (OCWLI) in labeled hydrogen-filled graphs (LHFGs) models of toxicity for 33 aldehydes were constructed. The toxicity endpoint was Tetrahymena pyriformis, a protozoan. The training set included 16 chemicals and the test set 17. As local invariants of the LHFGs we considered extended connectivity values of various orders and nearest neighboring codes (NNC). The best model of toxicity was obtained using the NNC. (C) 2004 Elsevier B.V. All rights reserved.
The nearest neighbouring code (NNC) is a local graph invariant. The NNC of a given vertex of the labelled hydrogen-filled graph is a function of the atom composition of vertex neighbours. We evaluated the suitability ...
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The nearest neighbouring code (NNC) is a local graph invariant. The NNC of a given vertex of the labelled hydrogen-filled graph is a function of the atom composition of vertex neighbours. We evaluated the suitability of this approach in quantitative structure-activity relationship models studying aldebyde toxicity towards fish, using aliphatic (saturated and non) as well as aromatic compounds. By optimisation of correlation weights of different atoms and different values of the NNCs, one-variable models of aldehyde toxicity have been obtained. The statistical characteristics of the model are the following: n = 25, r = 0.853, s = 0.515, F = 61 (training set) and n = 26, r = 0.802, s = 0.421, F = 43 (test set). (C) 2004 Published by Elsevier B.V.
作者：
Toropov, AARoy, KJadavpur Univ
Dept Pharmaceut Technol Div Med Chem & Pharmaceut Drug Theoret & Cheminformat Lab Kolkata 700032 W Bengal India Uzbek Acad Sci
Res Inst Algorithm Engn Tashkent 700125 Uzbekistan
The optimization of correlation weights scheme was applied to model lipid-water partition coefficient (log P) of two sets of diverse functional aliphatic and aromatic compounds. In both cases, the optimized descriptor...
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The optimization of correlation weights scheme was applied to model lipid-water partition coefficient (log P) of two sets of diverse functional aliphatic and aromatic compounds. In both cases, the optimized descriptors formulated based on the data of training sets generated statistically acceptable relations for the corresponding training sets, test sets, and combined sets. When the relations of log P values with the optimized molecular descriptors formulated based on the data of the training sets were used for calculation of log P values of the corresponding training sets, r(pred)(2) values were found to be satisfactory (above 0.99) in both cases, which is indicative of the predictive potential of the scheme. Tire results indicate promising potential of the optimization of a correlation weights scheme in modeling studies.
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