Geometria de superfícies isentrópicas

A dinâmica topológica de inversões geométricas foi estudada em [6]. O espa ̧co de parâmetros das medidas de Markov com suporte no atrator do sistema é um aberto de R3 folheado por superfícies de nível compactas definidas pela entropia métrica: superfícies isentrópicas [7]. Neste artigo abordaremos o aspecto geométrico dessas superfícies. Em particular, classificaremos suas geodésicas e pontos umbílicos.

Deyvisson Ribeiro

Edge-Disjoint Tree Realization of Tree Degree Matrices that avoid routine induction

Identifying whether a degree matrix has an edge-disjoint realization is an NP-hard problem. In comparison, identifying whether a tree degree matrix has an edge-disjoint realization is easier, but the task is still challenging. In 1975, a sufficient condition for the tree degree matrices with three rows has been found, but the condition has not been improved since. This paper contains an essential part of the proof which improves the sufficient condition.

Ian Seong

Women and mathematics at the Universities in Prague

This study is focused on lives of twelve women who prepared their doctorates in mathematics at the Faculty of Philosophy of the German University in Prague in the years 1882–1945, respectively at the Faculty of Science of the Czech University in Prague in the years 1882–1920 and 1921–1945 (known as Charles University in Prague in the latter period). In the first part, a short description of the historical background about women's studies at the universities in the Czech lands and a statistical overview of all PhD degrees in mathematics awarded at both universities in Prague is given for a better understanding of the situation with women's doctoral procedures. In the second part, a description of the successful doctoral procedures in mathematics of three women at the German University in Prague and of eight women at Charles University in Prague, as well as one unsuccessful doctoral procedure, are presented.

Martina Bečvářová

Human Influence on Predator-Prey Relationship: Red Panda and Snow Leopard

This research is a mathematical model based upon the human influence on the predator-prey relationship between Red Panda and Snow Leopard, which are the major species in the mountain ecosystem. This research explores if these species get extinct in a certain area due to imbalance in their interaction. Firstly, simple model of the species is discussed with no interaction between the species. Interactive model is then introduced to simulate their population when they interact with each other. The human influence is then introduced to the interactive model to observe if the species get extinct. This research is a mathematical model based upon the human influence on the predator-prey relationship between Red Panda and Snow Leopard, which are the major species in the mountain ecosystem. This research explores if these species get extinct in a certain area due to imbalance in their interaction. Firstly, simple model of the species is discussed with no interaction between the species. Interactive model is then introduced to simulate their population when they interact with each other. The human influence is then introduced to the interactive model to observe if the species get extinct. All the models are simulated in python programs using Euler's method. The data in this research are approximated for a certain area based upon the population density and habitat of the two species. All the models are simulated in python programs using Euler's method.

Jagat Kafle