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27922. On zeros of characters of finite groups
- Creator:
- Zhang, Jinshan, Shen, Zhencai, and Liu, Dandan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- finite groups, characters, and zeros
- Language:
- English
- Description:
- For a finite group $G$ and a non-linear irreducible complex character $\chi $ of $G$ write $\upsilon (\chi )=\{g\in G\mid \chi (g)=0\}$. In this paper, we study the finite non-solvable groups $G$ such that $\upsilon (\chi )$ consists of at most two conjugacy classes for all but one of the non-linear irreducible characters $\chi $ of $G$. In particular, we characterize a class of finite solvable groups which are closely related to the above-mentioned question and are called solvable $\varphi $-groups. As a corollary, we answer Research Problem $2$ in [Y. Berkovich and L. Kazarin: Finite groups in which the zeros of every non-linear irreducible character are conjugate modulo its kernel. Houston J. Math.\ 24 (1998), 619--630.] posed by Y. Berkovich and L. Kazarin.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27923. On |A, δ|k-summability of orthogonal series
- Creator:
- Krasniqi, Xhevat Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- orthogonal series and matrix summability
- Language:
- English
- Description:
- In the paper, we prove two theorems on |A, δ|k summability, 1 ≤ k ≤ 2, of orthogonal series. Several known and new results are also deduced as corollaries of the main results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27924. On γ-labelings of oriented graphs
- Creator:
- Okamoto, Futaba, Zhang, Ping, and Saenpholphat, Varaporn
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- oriented graph, γ-labeling, balanced γ-labeling, balanced oriented graph, and orientably balanced graph
- Language:
- English
- Description:
- Let D be an oriented graph of order n and size m. A γ-labeling of D is a one-to-one function f : V (D) → {0, 1, 2, . . . , m} that induces a labeling f ' : E(D) → {±1, ±2, . . . , ±m} of the arcs of D defined by f ' (e) = f(v) − f(u) for each arc e = (u, v) of D. The value of a γ-labeling f is val(f) = ∑ e∈E(G) f ' (e). A γ-labeling of D is balanced if the value of f is 0. An oriented graph D is balanced if D has a balanced labeling. A graph G is orientably balanced if G has a balanced orientation. It is shown that a connected graph G of order n ≥ 2 is orientably balanced unless G is a tree, n ≡ 2 (mod 4), and every vertex of G has odd degree.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27925. On ⋆-associated comonotone functions
- Creator:
- Hutník, Ondrej and Pócs, Jozef
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- comonotone functions, binary operation, ⋆-associatedness, and Sugeno integral
- Language:
- English
- Description:
- We give a positive answer to two open problems stated by Boczek and Kaluszka in their paper \cite{BK}. The first one deals with an algebraic characterization of comonotonicity. We show that the class of binary operations solving this problem contains any strictly monotone right-continuous operation. More precisely, the comonotonicity of functions is equivalent not only to +-associatedness of functions (as proved by Boczek and Kaluszka), but also to their ⋆-associatedness with ⋆ being an arbitrary strictly monotone and right-continuous binary operation. The second open problem deals with an existence of a pair of binary operations for which the generalized upper and lower Sugeno integrals coincide. Using a fairly elementary observation we show that there are many such operations, for instance binary operations generated by infima and suprema preserving functions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27926. On, Adolf Loos =
- Creator:
- Kriegerbeck, Bořivoj,
- Type:
- text, autobiografie, and deníky
- Subject:
- Stavebnictví, Biografie, Kriegerbeck, Bořivoj,, Loos, Adolf,, stavitelé, architekti, Československo 1918-1938, and architektura, architekti
- Language:
- Czech and English
- Rights:
- unknown
27927. On-line calibration of sliding star
- Creator:
- Valášek, Michael, Šika, Zbyněk, Štembera, Jiří, and Štefan, Marek
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parallel kinematics, calibration, non-redundant calibration, redundant calibration, on-line calibration, and Sliding Star
- Language:
- English
- Description:
- The paper deals with the calibration methods for machines with parallel kinematics. The procedures are based on Newton method for numerical solution of overconstrained system of nonlinear equations. The methods are applied on redundantly actuated machine with planar kinematics named ‘Sliding Star‘. The redundant measurements of relative motions in joints allow on-line calibration in real time of machine tool operation. This could significantly improve the thermal inaccuracy of machine tools with parallel mechanisms. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27928. On-line mixture-based alternative to logistic regression
- Creator:
- Nagy, I. and Suzdaleva , E.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- on-line modeling, on-line logistic regression, recursive mixture estimation, and data dependent pointer
- Language:
- English
- Description:
- The paper deals with a problem of modeling discrete variables depending on continuous variables. This problem is known as the logistic regression estimated by numerical methods. The paper approaches the problem via the recursive Bayesian estimation of mixture models with the purpose of exploring a possibility of constructing the continuous data dependent switching model that should be estimated on-line. Here the model of the discrete variable dependent on continuous data is represented as the model of the mixture pointer dependent on data from mixture components via their parameters, which switch according to the activity of the components. On-line estimation of the data dependent pointer model has a great potential for tasks of clustering and classification. The specific subproblems include (i) the model parameter estimation both of the pointer and of the components obtained during the learning phase, and (ii) prediction of the pointer value during the testing phase. These two phases can be joined together in the case of necessity. A real-data experimental comparison with theoretical counterparts shows a competitiveness of the approach in the discussed field.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27929. On-line path planning for mobile robots in dynamic environments
- Creator:
- Raja, P. and Pugazhenthi , S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Mobile robot, on-line path planning, and dynamic constraints and particle swarm optimization
- Language:
- English
- Description:
- Motion planning of mobile robots is a complex problem. The complexity further increases when it comes to path planning in dynamic environments. This paper presents an algorithm for on-line path planning of mobile robots in unknown environments with moving obstacles. A mathematical model is established which considers all the current on-line information of robot as well as nearing obstacles. Particle Swarm Optimization technique is used to optimize the velocity parameters of the robot, to arrive at the shortest collision-free trajectory, satisfying dynamic constraints. Simulation results show that the proposed algorithm is computationally efficient and effective.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27930. On-off intermittency in continuum systems driven by the Chen system
- Creator:
- Zhou, Qian, Chen, Zeng-Qiang, and Yuan, Zhu-Zhi
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- on-off intermittency, Chen system, Blowout bifurcation, intermingled basin, and power law
- Language:
- English
- Description:
- Previous studies on on-off intermittency in continuum systems are generally based on the synchronization of identical chaotic oscillators or in nonlinear systems driven by the Duffing oscillator. In this paper, one-state on-off intermittency and two-state on-off intermittency are observed in two five-dimensional continuum systems, respectively, where each system has a two-dimensional subsystem driven by the chaotic Chen system. The phenomenon of intermingled basins is observed below the blowout bifurcation. Basic statistical properties of the intermittency are investigated. It is shown that the distribution of the laminar phase follows a -3/2 power law, and that of the burst amplitudes follows a -1 power law, consistent with the basic statistical characteristics of on-off intermittency.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public