scholarly journals Combinatorial analysis of the permutations with a fixed number of cycles

2020 ◽  
pp. 110
Author(s):  
Наталия Юрьевна Энатская ◽  
Natalia Enatskaya
Keyword(s):  
Fixed Number ◽  
Combinatorial Analysis ◽  
Number Of Cycles

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 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

scholarly journals An Erdős-Ko-Rado Theorem for Permutations with Fixed Number of Cycles

10.37236/4071 ◽  
2014 ◽  
Vol 21 (3) ◽  
Author(s):  
Cheng Yeaw Ku ◽  
Kok Bin Wong
Keyword(s):  
Positive Integer ◽  
Fixed Points ◽  
Fixed Number ◽  
Stirling Number ◽  
Disjoint Cycles ◽  
Set Of Permutations ◽  
Common Cycles ◽  
Number Of Cycles ◽  
Positive Integers

Let $S_{n}$ denote the set of permutations of $[n]=\{1,2,\dots, n\}$. For a positive integer $k$, define $S_{n,k}$ to be the set of all permutations of $[n]$ with exactly $k$ disjoint cycles, i.e.,\[ S_{n,k} = \{\pi \in S_{n}: \pi = c_{1}c_{2} \cdots c_{k}\},\] where $c_1,c_2,\dots ,c_k$ are disjoint cycles. The size of $S_{n,k}$ is $\left [ \begin{matrix}n\\ k \end{matrix}\right]=(-1)^{n-k}s(n,k)$, where $s(n,k)$ is the Stirling number of the first kind. A family $\mathcal{A} \subseteq S_{n,k}$ is said to be $t$-cycle-intersecting if any two elements of $\mathcal{A}$ have at least $t$ common cycles. In this paper we show that, given any positive integers $k,t$ with $k\geq t+1$, if $\mathcal{A} \subseteq S_{n,k}$ is $t$-cycle-intersecting and $n\ge n_{0}(k,t)$ where $n_{0}(k,t) = O(k^{t+2})$, then \[ |\mathcal{A}| \le \left [ \begin{matrix}n-t\\ k-t \end{matrix}\right],\]with equality if and only if $\mathcal{A}$ is the stabiliser of $t$ fixed points.

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 On the extremal cactus graphs for variable sum exdeg index with a fixed number of cycles

2020 ◽  
Vol 17 (3) ◽  
pp. 920-923
Author(s):  
Mubeen Javaid ◽  
Akbar Ali ◽  
Igor Milovanović ◽  
Emina Milovanović
Keyword(s):  
Fixed Number ◽  
Cactus Graphs ◽  
Number Of Cycles

The Shifted Turán Sieve Method on Tournaments

2019 ◽  
Vol 62 (4) ◽  
pp. 841-855
Author(s):  
Wentang Kuo ◽  
Yu-Ru Liu ◽  
Sávio Ribas ◽  
Kevin Zhou
Keyword(s):  
Upper Bounds ◽  
Fixed Number ◽  
Sieve Method ◽  
Counting Problems ◽  
Number Of Cycles

AbstractWe construct a shifted version of the Turán sieve method developed by R. Murty and the second author and apply it to counting problems on tournaments. More precisely, we obtain upper bounds for the number of tournaments which contain a fixed number of restricted $r$-cycles. These are the first concrete results which count the number of cycles over “all tournaments”.

scholarly journals Modification and Actuator Minimization of the Hip Leg Joint in a Bipedal Robot: A Proposed Design

2014 ◽  
Vol 4 (2) ◽  
pp. 93
Author(s):  
Nirmalya Tripathi
Keyword(s):  
Cost Reduction ◽  
Fixed Number ◽  
Stepper Motor ◽  
Bipedal Robot ◽  
Biped Robots ◽  
Clockwise Direction ◽  
Stepper Motors ◽  
Novel Method ◽  
Number Of Cycles ◽  
The Cost

In recent times, there have been numeric applications of Biped Robots. In this paper, a proposed upper leg hip design of a biped was developed taking cost reduction and optimization as factors for consideration. The proposed system introduces a novel method which consists of a vibration reduction (VR) DC stepper motor, microcontroller, microprocessor and gearing arrangement. The program in the microprocessor is so designed that it gives a fixed number of cycles/steps to the VR DC stepper motor in clockwise and thereafter in anti-clockwise direction. This turning movement can then be transmitted to the gearing system which precisely moves one upper leg when the VR DC stepper motor moves in clockwise direction, while the other upper leg remains static, and vice-versa. It has been observed that this new proposed system may reduce the cost overhead, weight and the energy consumption incurred by working on a single VR DC stepper motor while conventionally two stepper motors are used to give the motion of the two upper legs in a biped.

Neoadjuvant chemotherapy without a fixed number of cycles in advanced ovarian cancer not candidates for optimal primary surgery.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e15552-e15552
Author(s):  
Cesar Mendiola ◽  
Ray Manneh ◽  
Tomas Pascual ◽  
Guillermo De Velasco ◽  
Estela Vega ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Neoadjuvant Chemotherapy ◽  
Survival Rates ◽  
Surrogate Marker ◽  
Advanced Ovarian Cancer ◽  
Fixed Number ◽  
Debulking Surgery ◽  
Stage Iiic ◽  
Term Survival ◽  
Number Of Cycles

e15552 Background: Neoadjuvant chemotherapy (N-CT) is a valid alternative for patients with advanced ovarian cancer (AOC) getting similar survival rates to primary debulking surgery (PDS) followed by chemotherapy (CT), with less postoperatory complications (Vergote et al N Engl J Med 2010;363:943-53). Our objective was to evaluate the results of N-CT with a flexible number of cycles according to the clinical and biological evolution of the patients. Methods: 22 patients with stage IIIC-IV AOC, diagnosed by laparoscope or cytology (no primary laparotomy) were registered between January 2007 and September 2011 and treated with N-CT including paclitaxel 175 mg/m2 and carboplatin AUC 6-5 every 3 weeks. The number of cycles of N-CT was dictated by the clinical response, CT scan and CA125 that could allow an interval debulking surgery (IDS) with intent of optimal cytoreduction (R0). After IDS consolidation chemotherapy treatment was given to complete a total of at least 8 cycles. Results: Median age 63.7 years (40 – 80). Histologic types: serous 28%, adenocarcinoma not specified 66%, endometrioid 4.5%. FIGO stage IIIC 57%, IV 43%, Median CA125 at diagnosis: 1744 U (157 – 14483). Mean N-CT cycles 7.8 (4-23). 90.1 % of patients responded before IDS, 2 patients progressed before surgery. Mean CA125 after N-CT was 20.5 U (9-108). 54% of patients achieved complete resection of all macroscopic disease during IDS (R0). 5/22 (22.7%) obtained a pathological complete response (pCR) (no microscopic tumour in all specimens removed). Complications in the postoperatory occurred in 2 patients consisting in suture dehiscence. The range of total number of CT cycles were as follows: <6: 4.54%; 7-8: 31.8%; 9-10: 31.8%, >10: 31.8%. With a mean follow-up of 22.4 months (4 - 57.6), 50% patients live without recurrence. Median PFS has not been reached. Conclusions: N-CT according to clinical and biologic response and not to a fixed number of cycles is an useful tool for patients with stage IIIC-IV AOC not candidates for optimal /R0 PDS, getting a high proportion of patients with optimal /R0 IDS. The complications of IDS are also very limited. pCR as surrogate marker for long-term survival in other tumours, has to be evaluated in AOC.

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