Giriş gösterimlerinin kendini örgütleyen ve aşağıdan yukarıya çalışan akor şemalarına etkisi

Effects of input representation on self-organizing and bottom-up model of chord schema were investigated. A single layer self-organizing map was trained with 12 major and 12 minor chords. Training was repeated five times, each time with a different input representation. In this model, activation of chords is determined by the representation and activation of pitches that compose the chords. Important findings of chord perception were simulated with this model. Simulation results showed that input representation was critical to simulate all of the findings.Giriş gösterimlerinin kendini örgütleyen ve aşağıdan yukarıya çalışan akor şemalarına etkisi incelenmiştir. Tek katmanlı kendini örgütleyen ağ 12 major ve 12 minör akor ile eğitilmiştir. Eğitim her seferinde başka bir giriş gösterimi kullanılarak beş kez tekrar edilmiştir. Bu modelde akor gösterimlerinin seviyesi sadece akoru oluşturan seslerin gösterimleri ve seviyesi ile belirlenmektedir. Akor algısının önemli bulguları bu model ile benzetilmiştir. Benzetim sonuçları göstermektedir ki bütün bulguların modellenebilmesi için uygun giriş gösterimlerinin seçilmesi gerekmektedir

On the Rigidity of Disordered Networks

abstract: The rigidity of a material is the property that enables it to preserve its structure when deformed. In a rigid body, no internal motion is possible since the degrees of freedom of the system are limited to translations and rotations only. In the macroscopic scale, the rigidity and response of a material to external load can be studied using continuum elasticity theory. But when it comes to the microscopic scale, a simple yet powerful approach is to model the structure of the material and its interparticle interactions as a ball$-$and$-$spring network. This model allows a full description of rigidity in terms of the vibrational modes and the balance between degrees of freedom and constraints in the system. In the present work, we aim to establish a microscopic description of rigidity in \emph{disordered} networks. The studied networks can be designed to have a specific number of degrees of freedom and/or elastic properties. We first look into the rigidity transition in three types of networks including randomly diluted triangular networks, stress diluted triangular networks and jammed networks. It appears that the rigidity and linear response of these three types of systems are significantly different. In particular, jammed networks display higher levels of self-organization and a non-zero bulk modulus near the transition point. This is a unique set of properties that have not been observed in any other types of disordered networks. We incorporate these properties into a new definition of jamming that requires a network to hold one extra constraint in excess of isostaticity and have a finite non-zero bulk modulus. We then follow this definition by using a tuning by pruning algorithm to build spring networks that have both these properties and show that they behave exactly like jammed networks. We finally step into designing new disordered materials with desired elastic properties and show how disordered auxetic materials with a fully convex geometry can be produced.Dissertation/ThesisDoctoral Dissertation Physics 201