Priority Research Centre for Computer-AssistedResearch Mathematics and its Applications
 Member Links: (login required) Members Area CARMA News Manager CARMA Web Logs CARMA Seminar Manager CARMA Wiki Subscribe to our seminar mailing list Subscribe to our events calendar (iCal format)

### CARMA-Sponsored Seminar Series: Colloquia, Seminars and More.

[Note: events are listed by descending date.]
 AUSTRALIAN MATHEMATICAL SCIENCES STUDENT CONFERENCE Keynote Lecture Speaker: A/Prof Matthew Simpson, Discipline of Mathematical Sciences, Queensland University of Technology Title: Mathematical models of transport through crowded environments Location: Room V07, Mathematics Building (Callaghan Campus) The University of Newcastle Time and Date: 10:00 am, Fri, 4th Jul 2014 Abstract: Many biological environments, both intracellular and extracellular, are often crowded by large molecules or inert objects which can impede the motion of cells and molecules. It is therefore essential for us to develop appropriate mathematical tools which can reliably predict and quantify collective motion through crowded environments. Transport through crowded environments is often classified as anomalous, rather than classical, Fickian diffusion. Over the last 30 years many studies have sought to describe such transport processes using either a continuous time random walk or fractional order differential equation. For both these models the transport is characterized by a parameter $\alpha$, where $\alpha=1$ is associated with Fickian diffusion and $\alpha<1$ is associated with anomalous subdiffusion. In this presentation we will consider the motion of a single agent migrating through a crowded environment that is populated by impenetrable, immobile obstacles and we estimate $\alpha$ using mean squared displacement data. These results will be compared with computer simulations mimicking the transport of a population of such agents through a similar crowded environment and we match averaged agent density profiles to the solution of a related fractional order differential equation to obtain an alternative estimate of $\alpha$. I will examine the relationship between our estimate of $\alpha$ and the properties of the obstacle field for both a single agent and a population of agents; in both cases $\alpha$ decreases as the obstacle density increases, and that the rate of decrease is greater for smaller obstacles. These very simple computer simulations suggests that it may be inappropriate to model transport through a crowded environment using widely reported approaches including power laws to describe the mean squared displacement and fractional order differential equations to represent the averaged agent density profiles. More details can be found in Ellery, Simpson, McCue and Baker (2014) The Journal of Chemical Physics, 140, 054108. [Permanent event link] AUSTRALIAN MATHEMATICAL SCIENCES STUDENT CONFERENCE Keynote Lecture Speaker: Dr Vera Roshchina, Collaborative Research Network, The University of Ballarat Title: Geometric properties of ill-posed conic system Location: Room V07, Mathematics Building (Callaghan Campus) The University of Newcastle Time and Date: 10:00 am, Thu, 3rd Jul 2014 Abstract: I will talk about the geometric properties of conic problems and their interplay with ill-posedness and the performance of numerical methods. This includes some new results on the facial structure of general convex cones, preconditioning of feasibility problems and characterisations of ill-posed systems. [Permanent event link] AUSTRALIAN MATHEMATICAL SCIENCES STUDENT CONFERENCE Public Lecture Speaker: Prof Brian Alspach, CARMA, The University of Newcastle Title: Lost Spelunkers, Cops And Robbers and Is Someone Trying To Destroy My Network? Location: Room V07, Mathematics Building (Callaghan Campus) The University of Newcastle Time and Date: 6:30 pm, Wed, 2nd Jul 2014 Abstract: What do the three elements of the title have in common is the utility of using graph searching as a model. In this talk I shall discuss the relatively brief history of graph searching, several models currently being employed, several significant results, unsolved conjectures, and the vast expanse of unexplored territory. [Permanent event link] AUSTRALIAN MATHEMATICAL SCIENCES STUDENT CONFERENCE Keynote Lecture Speaker: Dr Michael Coons, CARMA, The University of Newcastle Title: My life in \$mathmode\$ Location: Room V07, Mathematics Building (Callaghan Campus) The University of Newcastle Time and Date: 10:00 am, Wed, 2nd Jul 2014 Abstract: I will survey my career both mathematically and personally offering advice and opinions, which should probably be taken with so many grains of salt that it makes you nauseous. (Note: Please bring with you a sense of humour and all of your preconceived notions of how your life will turn out. It will be more fun for everyone that way.) [Permanent event link] AUSTRALIAN MATHEMATICAL SCIENCES STUDENT CONFERENCE AMSSC2014 Location: Mathematics Building (Callaghan Campus) The University of Newcastle Dates: Wed, 2nd Jul 2014 - Fri, 4th Jul 2014 The Australian Mathematical Sciences Student Conference is held annually for Australian postgraduate and honours students of any mathematical science. The conference brings students together, gives an opportunity for presentation of work, facilitates dialogue, and encourages collaboration, within a friendly and informal atmosphere. Visit the conference website for more details. [Permanent event link]