scholarly journals Preserving the Number of Cycles of Length $k$ in a Growing Uniform Permutation

10.37236/6014 ◽  
2016 ◽  
Vol 23 (4) ◽  
Author(s):  
Philippe Duchon ◽  
Romaric Duvignau
Keyword(s):  
Poisson Distribution ◽  
Fixed Number ◽  
Optimal Size ◽  
Random Generation ◽  
Combinatorial Algorithm ◽  
Generation Algorithm ◽  
Exact Sampling ◽  
Random Integer ◽  
Uniform Generation ◽  
Number Of Cycles

The goal of this work is to describe a uniform generation tree for permutations which preserves the number of $k$-cycles between any permutation (except for a small unavoidable subset of optimal size) of the tree and its direct children. Moreover, the tree we describe has the property that if the number of $k$-cycles does not change during any $k$ consecutive levels, then any further random descent will always yield permutations with that same number of $k$-cycles. This specific additional property yields interesting applications for exact sampling. We describe a new random generation algorithm for permutations with a fixed number of $k$-cycles in $n+\mathcal{O}(1)$ expected calls to a random integer sampler. Another application is a combinatorial algorithm for exact sampling from the Poisson distribution with parameter $1/k$.

scholarly journals A new generation tree for permutations, preserving the number of fixed points

2014 ◽  
Vol DMTCS Proceedings vol. AT,... (Proceedings) ◽  
Author(s):  
Philippe Duchon ◽  
Romaric Duvignau
Keyword(s):  
Fixed Points ◽  
Random Number ◽  
Random Number Generator ◽  
Specific Property ◽  
Number Generator ◽  
Random Generation ◽  
Combinatorial Algorithm ◽  
International Audience ◽  
Uniform Generation ◽  
New Generation

International audience We describe a new uniform generation tree for permutations with the specific property that, for most permutations, all of their descendants in the generation tree have the same number of fixed points. Our tree is optimal for the number of permutations having this property. We then use this tree to describe a new random generation algorithm for derangements, using an expected n+O(1) calls to a random number generator. Another application is a combinatorial algorithm for exact sampling from the Poisson distribution with parameter 1.

scholarly journals On Exact Sampling of Nonnegative Infinitely Divisible Random Variables

2012 ◽  
Vol 44 (3) ◽  
pp. 842-873 ◽  
Author(s):  
Zhiyi Chi
Keyword(s):  
Basic Result ◽  
Random Variables ◽  
Random Variable ◽  
Fixed Number ◽  
Rejection Sampling ◽  
Infinitely Divisible ◽  
Exact Sampling ◽  
Special Cases ◽  
Wide Range ◽  
Lévy Density

Nonnegative infinitely divisible (i.d.) random variables form an important class of random variables. However, when this type of random variable is specified via Lévy densities that have infinite integrals on (0, ∞), except for some special cases, exact sampling is unknown. We present a method that can sample a rather wide range of such i.d. random variables. A basic result is that, for any nonnegative i.d. random variable X with its Lévy density explicitly specified, if its distribution conditional on X ≤ r can be sampled exactly, where r > 0 is any fixed number, then X can be sampled exactly using rejection sampling, without knowing the explicit expression of the density of X. We show that variations of the result can be used to sample various nonnegative i.d. random variables.

Aeroelastic flutter control of a bridge using rotating mass dampers and winglets

2020 ◽  
Vol 26 (23-24) ◽  
pp. 2185-2192
Author(s):  
Kamal K Bera ◽  
Naresh K Chandiramani
Keyword(s):  
Angular Speed ◽  
Fixed Number ◽  
Control Input ◽  
Vertical Force ◽  
Flat Plates ◽  
Aeroelastic Flutter ◽  
Continuous Rotation ◽  
Rational Function Approximation ◽  
Number Of Cycles ◽  
The Time Domain

Flutter control of a bridge deck section using a combination of aerodynamic and mechanical measures, that is controllable winglets and rotating mass dampers, is considered. Deck and winglets are considered as flat plates for their aerodynamics. Self-excited wind forces are represented in the time domain using the Scanlan–Tomko model with Roger’s rational function approximation for flutter derivatives. Winglet rotation relative to the deck is the control input generated by the variable-gain output feedback controller that uses vertical and torsional displacements of the deck as measured outputs. Control using winglets enhances the critical speed to twice the uncontrolled flutter speed. Further attenuation of vertical response is obtained by using rotating mass dampers configured to provide only a resultant vertical force due to counter-rotating unbalanced masses. The rotors are driven at a constant angular speed, and start–stop criteria are applied. This generates additional vertical force on the deck that is mostly out of phase with its vertical velocity. It yields better control than the damper operated in a continuous rotation mode for a fixed number of cycles. A maximum reduction of 15% in root mean square vertical response is obtained when compared with control using winglets only.

scholarly journals Edge Mostar Indices of Cacti Graph With Fixed Cycles

2021 ◽  
Vol 9 ◽  
Author(s):  
Farhana Yasmeen ◽  
Shehnaz Akhter ◽  
Kashif Ali ◽  
Syed Tahir Raza Rizvi
Keyword(s):  
Upper Bound ◽  
Connected Graph ◽  
Thermodynamic Characteristics ◽  
Chemical Compounds ◽  
Fixed Number ◽  
Common Vertex ◽  
Topological Invariants ◽  
Cactus Graph ◽  
Number Of Cycles

Topological invariants are the significant invariants that are used to study the physicochemical and thermodynamic characteristics of chemical compounds. Recently, a new bond additive invariant named the Mostar invariant has been introduced. For any connected graph ℋ, the edge Mostar invariant is described as Moe(ℋ)=∑gx∈E(ℋ)|mℋ(g)−mℋ(x)|, where mℋ(g)(or mℋ(x)) is the number of edges of ℋ lying closer to vertex g (or x) than to vertex x (or g). A graph having at most one common vertex between any two cycles is called a cactus graph. In this study, we compute the greatest edge Mostar invariant for cacti graphs with a fixed number of cycles and n vertices. Moreover, we calculate the sharp upper bound of the edge Mostar invariant for cacti graphs in ℭ(n,s), where s is the number of cycles.

scholarly journals 3 Introducing Primality Testing Algorithm with an Implementation on 64 bits RSA Encryption Using Verilog

2018 ◽  
Vol 1 (1) ◽  
pp. 6
Author(s):  
Rehan Shams ◽  
Fozia Hanif Khan ◽  
Umair Jillani ◽  
M. Umair
Keyword(s):  
Communication System ◽  
Prime Numbers ◽  
Key Generation ◽  
Random Generation ◽  
Primality Testing ◽  
Rsa Algorithm ◽  
Encryption And Decryption ◽  
Number Of Cycles ◽  
Testing Algorithm ◽  
Secured Communication

A new structure to develop 64-bit RSA encryption engine on FPGA is being presented in this paper that can be used as a standard device in the secured communication system. The RSA algorithm has three parts i.e. key generation, encryption and decryption. This procedure also requires random generation of prime numbers, therefore, we are proposing an efficient fast Primality testing algorithm to meet the requirement for generating the key in RSA algorithm. We use right-to-left-binary method for the exponent calculation. This reduces the number of cycles enhancing the performance of the system and reducing the area usage of the FPGA. These blocks are coded in Verilog and are synthesized and simulated in Xilinx 13.2 design suit.

scholarly journals Theorizing Probability Distribution in Applied Statistics

2020 ◽  
Vol 1 (1) ◽  
pp. 79-95
Author(s):  
Indra Malakar
Keyword(s):  
Probability Distribution ◽  
Normal Distribution ◽  
Poisson Distribution ◽  
Binomial Distribution ◽  
Identical Condition ◽  
Random Variable ◽  
Fixed Number ◽  
Theoretical Knowledge ◽  
Applied Statistics ◽  
Discrete Random Variable

This paper investigates into theoretical knowledge on probability distribution and the application of binomial, poisson and normal distribution. Binomial distribution is widely used discrete random variable when the trails are repeated under identical condition for fixed number of times and when there are only two possible outcomes whereas poisson distribution is for discrete random variable for which the probability of occurrence of an event is small and the total number of possible cases is very large and normal distribution is limiting form of binomial distribution and used when the number of cases is infinitely large and probabilities of success and failure is almost equal.

scholarly journals Correlation between Thermal Behaviour of AA5754-H111 during Fatigue Loading and Fatigue Strength at Fixed Number of Cycles

Materials ◽  
2018 ◽  
Vol 11 (5) ◽  
pp. 719 ◽  
Author(s):  
Rosa De Finis ◽  
Davide Palumbo ◽  
Livia Serio ◽  
Luigi De Filippis ◽  
Umberto Galietti
Keyword(s):  
Fatigue Strength ◽  
Thermal Behaviour ◽  
Fatigue Loading ◽  
Fixed Number ◽  
Number Of Cycles
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