The triplet distance is a distance measure that compares two rooted trees on the same set of leaves by enumerating all sub-sets of three leaves and counting how often the induced topologies of the tree are equal or di...
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The triplet distance is a distance measure that compares two rooted trees on the same set of leaves by enumerating all sub-sets of three leaves and counting how often the induced topologies of the tree are equal or different. We present an algorithm that computes the triplet distance between two rooted binary trees in time O (n log(2) n). The algorithm is related to an algorithm for computing the quartet distance between two unrooted binary trees in time O (n log n). While the quartet distance algorithm has a very severe overhead in the asymptotic time complexity that makes it impractical compared to O (n(2)) time algorithms, we show through experiments that the triplet distance algorithm can be implemented to give a competitive wall-time running time.
We study a set of scheduling problems in a distributed flow-shop scheduling system consisting of several flow-shop production systems (factories) working in parallel. Our objective is to assign the jobs to the factori...
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We study a set of scheduling problems in a distributed flow-shop scheduling system consisting of several flow-shop production systems (factories) working in parallel. Our objective is to assign the jobs to the factories, and to devise a job schedule for each of the factories such that the weighted number of jobs completed in just-in-time mode is maximized. We classify computational complexity of the problems, including the special cases of unit weights and job- or machine-independent processing times.
In this paper we introduce a problem called Quantified Integer Programming, which generalizes the Quantified Satisfiability problem (QSAT). In a Quantified Integer Program (QIP) the program variables can assume arbitr...
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In this paper we introduce a problem called Quantified Integer Programming, which generalizes the Quantified Satisfiability problem (QSAT). In a Quantified Integer Program (QIP) the program variables can assume arbitrary integral values, as opposed to the boolean values that are assumed by the variables of an instance of QSAT. QIPs naturally represent two-person integer matrix games. The Quantified Integer Programming problem is PSPACE-hard in general, since the QSAT problem is PSPACE-complete. Quantified Integer Programming can be thought of as a restriction of Presburger Arithmetic, in that we allow only conjunctions of linear inequalities. We focus on analyzing various special cases of the general problem, with a view to discovering subclasses that are tractable. Subclasses of the general QIP problem are obtained by restricting either the constraint matrix or quantifier specification or both. We show that if the constraint matrix is totally unimodular, the problem of deciding a QIP can be solved in polynomial time. We also establish the computational complexities of Oblivious strategy games and Clairvoyant strategy games.
In this paper, we consider the class of Boolean mu-functions, which are the Boolean functions definable by mu-expressions (Boolean expressions in which no variable occurs more than once). We present an algorithm which...
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In this paper, we consider the class of Boolean mu-functions, which are the Boolean functions definable by mu-expressions (Boolean expressions in which no variable occurs more than once). We present an algorithm which transforms a Boolean formula E into an equivalent mu-expression-if possible-in time linear in parallel to E parallel to times 2(nm), where parallel to E parallel to is the size of E and n(m) is the number of variables that occur more than once in E. As an application, we obtain a polynomial time algorithm for Mundici's problem of recognizing mu-functions from k-formulas [17]. Furthermore, we show that recognizing Boolean mu-functions is co-NP-complete for functions essentially dependent on all variables and we give a bound close to co-NP for the general case.
In this paper, we have developed an algorithm that proposes advance and novice security mechanism that can defend any kind of attacks and is advantageous over the other existing algorithms that are currently being use...
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ISBN:
(纸本)9781538630457
In this paper, we have developed an algorithm that proposes advance and novice security mechanism that can defend any kind of attacks and is advantageous over the other existing algorithms that are currently being used in security areas like email and web-based security applications. This algorithm is based on the concept of time in analog clock. The most powerful feature of this algorithm is 10506 (permutation of substitution clock). We implemented this algorithm in python. And after verification and validation we found out that it is impossible to crack by any kind of tool in existence. We are looking forward to use this algorithm in various applications.
At previous PTTI meeting, PTTI'17, we mentioned that VNIIFTRI has got four Rb fountain frequency standards, which run as frequency standards, not clocks. These instruments are not intended for secondary presentati...
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ISBN:
(纸本)9781538656204
At previous PTTI meeting, PTTI'17, we mentioned that VNIIFTRI has got four Rb fountain frequency standards, which run as frequency standards, not clocks. These instruments are not intended for secondary presentation of the time unit the second SI. These are indeed very stable frequency reference without frequency drift inherent, for example, to H-masers. During last year output frequency of these standards has been calibrated against operational CsF02 primary fountain frequency standard and now one may use these instruments as time and frequency unit keepers. This report will present preliminary results of the first experiments on application of Rb fountain frequency standards for maintenance the national atomic time scale TA(SU). According internal regulation TA(SU) is independent atomic time scale with the unit of time the second SU, reproduced by operational primary Cs fountain frequency standards. This time scale by-turn is maintained by ensemble of continuously operating high stable hydrogen masers. On other hand, each H-maser demonstrates more or less predictable frequency drift the value of which may be quite comparable to daily H-maser frequency stability. That is why one has times to times re-evaluate H-maser output frequency parameters. The more often one will re-evaluate H-maser output frequency parameters the more stable and accurate (in sense unit of time the second SU) time scale will be produced. The key problem is interruptible Cs standard mode of operation. Typically, Cs standard produces two or three sessions per month, but sometimes happens gaps for some months. In such cases availability of more or less continuously operating stable and none drifting frequency reference such as Rb fountain frequency standards may be a solution of the problem. The paper presents comparisons of some scenarios of TA(SU) maintenance: a. purely based on H-maser ensemble and primary Cs fountain frequency standards data and b. based on H-maser ensemble and Rb fountain f
In this paper, we have developed an algorithm that proposes advance and novice security mechanism that can defend any kind of attacks and is advantageous over the other existing algorithms that are currently being use...
详细信息
In this paper, we have developed an algorithm that proposes advance and novice security mechanism that can defend any kind of attacks and is advantageous over the other existing algorithms that are currently being used in security areas like email and web-based security applications. This algorithm is based on the concept of time in analog clock. The most powerful feature of this algorithm is 10~(506) (permutation of substitution clock). We implemented this algorithm in python. And after verification and validation we found out that it is impossible to crack by any kind of tool in existence. We are looking forward to use this algorithm in various applications.
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