Some Results on the Krein Parameters of an Association Scheme

نویسنده

  • Vasco Moço Mano
چکیده

We consider association schemes with d classes and the underlying BoseMesner algebra, A . Then, by taking into account the relationship between the Hadamard and the Kronecker products of matrices and making use of some matrix techniques over the idempotents of the unique basis of minimal orthogonal idempotents of A , we prove some results over the Krein parameters of an association scheme.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The Subconstituent Algebra of an Association Scheme, (Part I)

We introduce a method for studying commutative association schemes with "many" vanishing intersection numbers and/or Krein parameters, and apply the method to the Pand Qpolynomial schemes. Let Y denote any commutative association scheme, and fix any vertex x of Y. We introduce a non-commutative, associative, semi-simple C-algebra T = T(x) whose structure reflects the combinatorial structure of ...

متن کامل

Association Schemes with Multiple Q-polynomial Structures

It is well known that an association scheme X = (X, {Ri}0≤i≤d) with k1 > 2 has at most two P polynomial structures. The parametrical condition for an association scheme to have twoP -polynomial structures is also known. In this paper, we give a similar result for Q-polynomial association schemes. In fact, if d > 5, then we obtain exactly the same parametrical conditions for the dual intersectio...

متن کامل

Generalized Krein Parameters of a Strongly Regular Graph

We consider the real three-dimensional Euclidean Jordan algebra associated to a strongly regular graph. Then, the Krein parameters of a strongly regular graph are generalized and some generalized Krein admissibility conditions are deduced. Furthermore, we establish some relations between the classical Krein parameters and the generalized Krein parameters.

متن کامل

Protection Scheme of Power Transformer Based on Time–Frequency Analysis and KSIR-SSVM

The aim of this paper is to extend a hybrid protection plan for Power Transformer (PT) based on MRA-KSIR-SSVM. This paper offers a new scheme for protection of power transformers to distinguish internal faults from inrush currents. Some significant characteristics of differential currents in the real PT operating circumstances are extracted. In this paper, Multi Resolution Analysis (MRA) is use...

متن کامل

An Intelligent Anti-Islanding Scheme for Synchronous-Based Distributed Generation Using Reduced-Noise Morphological Gradient

This paper presents a pattern recognition-based scheme for detection of islanding conditions in synchronous- based distributed generation (DG) systems. The main idea behind the proposed scheme is the use of spatial features of system parameters such as the frequency, magnitude of positive sequence voltage, etc. In this study, the system parameters sampled at the point of common coupling (PCC) w...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2013