# Talks

### 2019

**High performance solution of large-scale linear programming problems**Invited seminar, Stirling, 1 November 2019**Using**INFORMS, Seattle, 22 October 2019`HiGHS`as an LP solver within`SCIP``HiGHS`: a high-performance linear optimizer

- INFORMS, Seattle, 21 October 2019
- ICCOPT, Berlin, 6 August 2019
- 28th Biennial Conference on Numerical Analysis, University of Strathclyde, Glasgow, 28 June 2019
- 30th European Conference on Operational Research, University College Dublin, 25 June 2019
- 2nd IMA and OR Society Conference on Mathematics of Operational Research, University of Aston, Birmingham, 26 April 2019

**Linear Programming solvers: the state of the art**

Julian Hall

Invited talk at 4th ISM-ZIB-IMI MODAL Workshop on Mathematical Optimization and Data Analysis Tokyo, 27 March 2019

### 2018

`HiGHS`: A High-Performance Linear Optimizer

Julian Hall

Contributed talk at OR60: The 60th OR Society Conference, 11-13 September 2018**Starting the dual revised simplex method from an advanced basis**

Julian Hall and Ivet Galabova

Contributed talk at the 23rd International Symposium on Mathematical Programming, Bordeaux, France, 1-6 July 2018**High performance numerical linear algebra for the revised simplex method**

Julian Hall

Plenary talk at NLAO18: 6th IMA Conference on Numerical Linear Algebra and Optimization, 27-29 June 2018**A quadratic penalty algorithm for linear programming and its application to linearizations of quadratic assignment problems**

Julian Hall and Ivet Galabova

Computational Optimization in Action, Edinburgh, 8 June 2018

### 2017

**Starting the dual revised simplex method from an advanced basis**

Julian Hall

Contributed talk at the 4th Conference on Optimization Methods and Software, Havana, Cuba, 16-20 December 2017**Fast solution of LP problems**

Julian Hall and Ivet Galabova

Zuse Institute Berlin, 10 October 2017**High performance numerical linear algebra for the revised simplex method**

Julian Hall

Workshop on Linear Algebra for PDEs and Optimization, Edinburgh, 4 September 2017**High performance solution of linear optimization problems**

Julian Hall

ALOP Autumn School, Trier, 31 August 2017**Three high performance simplex solvers**

Julian Hall

Public lecture, Tokyo, 14 August 2017**Novel update techniques for the revised simplex method**

Julian Hall and Qi Huangfu

Contributed talk at the 15th EUROPT Workshop on Advances in Continuous Optimization, 12-14 July 2017**An open-source high performance dual simplex solver**

Julian Hall, Qi Huangfu and Ivet Galabova

Contributed talk at SIAM Conference on Optimization, 22-25 May 2017**Three high performance simplex solvers**

Julian Hall and Ivet Galabova

Seminar at Argonne National Laboratory 16 May 2017

### 2016

**Novel update techniques for the revised simplex method (and their application)**

Q. Huangfu and J. A. J. Hall

School of Mathematics ERGO seminar: 30 November 2016**Parallelizing the dual revised simplex method**

J. A. J. Hall

Contributed talk at NLAO16: 5th IMA Conference on Numerical Linear Algebra and Optimization, 7-9 September 2016.**Parallel distributed-memory simplex for large-scale stochastic LP problems**

M. Lubin, J. A. J. Hall, C. G. Petra and M. Anitescu

Invited talk at The 5th International Congress on Mathematical Software, ICMS, 11-14 July 2016.

### 2015

**High performance simplex solvers for linear programming problems**

J. A. J. Hall

Technical talk: Google, Paris, 11 September 2015.

### 2014

**Parallel implementation of the dual revised simplex method for large-scale LP problems**

J. A. J. Hall

Contributed talk at NLAO14: 4th IMA Conference on Numerical Linear Algebra and Optimization, 4 September 2014.**Parallel distributed-memory simplex for large-scale stochastic LP problems**

J. A. J. Hall

Contributed talk at CSC14: The Sixth SIAM Workshop on Combinatorial Scientific Computing, Lyon, 21st July 2014.**Parallelising the dual revised simplex method**

J. A. J. Hall

Invited talk at the Convex Optimization and Beyond Workshop, ICMS, 27th June 2014.

### 2013

**A distributed parallel dual revised simplex solver for large scale stochastic MIP problems**

J. A. J. Hall

Contributed talk at the Computational Linear Algebra and Optimization for the Digital Economy Workshop, ICMS, 31st October-1st November 2013.**Parallelizing the revised simplex method: Is it time to give up?**

J. A. J. Hall

Contributed talk at ICCOPT 2013, Lisbon, Portugal: 1st August 2013

### 2012

**Parallel revised simplex for primal block angular LP problems**

J. A. J. Hall and E. Smith

Contributed talk at PMAA 2012, Birkbeck University of London, UK: 28th June 2012**Promoting hyper-sparsity in the revised simplex method**

J. A. J. Hall and Q. Huangfu

Contributed talk at APMOD 12, Paderborn, Germany: 28th March 2012

### 2011

**A high performance dual revised simplex solver**

J. A. J. Hall and Q. Huangfu

Contributed talk at the 9th International Conference on Parallel Processing and Applied Mathematics Conference: 13th September 2011**Matrix-free IPM with GPU acceleration**

J. A. J. Hall and E. Smith

Contributed talk at the Strathclyde Numerical Analysis Conference: 29th June 2011**High performance computing and the simplex method**

J. A. J. Hall, Q. Huangfu and E. Smith

Presentation at the LANCS Workshop on Modelling and Solving Complex Optimisation Problems: 12th April 2011

### 2010

**A high performance dual revised simplex solver**

J. A. J. Hall, Q. Huangfu and E. Smith

Invited Oxford University Computational Mathematics and Applications seminar, Rutherford Appleton Laboratory: 2nd December 2010**Towards a practical parallelisation of the revised simplex method**

J. A. J. Hall, E. Smith and Q. Huangfu

Contributed talk the IMA Conference on Numerical Linear Algebra and Optimisation: 14th September 2010**A parallel revised simplex solver for large scale block angular LP problems**

J. A. J. Hall and E. Smith

Computational Management Science 10 - Vienna: 29th July 2010**The Future of the Simplex Method**

J. A. J. Hall

Haute École de Gestion - Geneva, Seminar: 29th June 2010

### 2009

**The Mathematical legacy of ECOSSE**

J. A. J. Hall

ECOSSE Retrospective Symposium: 17th April 2009

### 2008

**High performance implementations of the simplex method for linear programming**

J. A. J. Hall

ENSEEIHT seminar: 8th April 2008**Computational linear optimization**

J. A. J. Hall

ENSEEIHT seminar: 2nd April 2008

### 2007

**Parallel solution of block angular LP problems using Kaul's algorithm**

İ. İ. Boduroğlu, J. A. J. Hall and J. D. Hogg

School of Mathematics ERGO seminar: 7th November 2007**Parallel basis matrix triangularisation for hyper-sparse LP problems**

J. A. J. Hall

Contributed talk the IMA Conference on Numerical Linear Algebra and Optimisation: 14th September 2007**Scalable massively parallel simplex algorithms for block-structured linear programs**

İ. İ. Boduroğlu, J. A. J. Hall and J. D. Hogg

Contributed talk the IMA Conference on Numerical Linear Algebra and Optimisation: 14th September 2007**Parallel basis matrix triangularisation for hyper-sparse LP problems**

J. A. J. Hall

Invited talk at the joint EUROPT-OMS Meeting 2007: 4th July 2007**Exploiting hyper-sparsity when computing preconditioners for conjugate gradients in interior point methods**

J. A. J. Hall, Ghussoun Al-Jeiroudi and Jacek Gondzio

Contributed talk at the Dundee Numerical Analysis Conference: 27th June 2007**Computational issues in linear programming**

J. A. J. Hall

Invited seminar at CERFACS: 15th May 2007**Computational linear optimization**

J. A. J. Hall

Maxwell Symposium on Computational Mathematics: 15th March 2007

### 2006

**Parallel matrix inversion for the revised simplex method - A study**

J. A. J. Hall

Contributed talk at the Sparse Days Meeting 2006 at CERFACS: 15th-16th June 2006

### 2005

**Parallelisation of the revised simplex method for general large scale LP problems**

J. A. J. Hall

Contributed talk at the International Conference on Numerical Optimization and Numerical Linear Algebra 2005 (ICNLAO 2005): 9-10th August 2005**SYNPLEX, a task-parallel scheme for the revised simplex method**

J. A. J. Hall

Contributed talk at the Second International Workshop on Combinatorial Scientific Computing (CSC05): 23rd June 2005**SYNPLEX, a task-parallel scheme for the revised simplex method**

J. A. J. Hall

ERGO seminar: 15th June 2005**Towards a practical parallelisation of the simplex method**

J. A. J. Hall

Invited seminar at the Mathematics Division, University of Dundee: 19th March 2005**The practical revised simplex method**

J. A. J. Hall

University of Edinburgh graduate seminar: 26th January 2005

### 2004

**Parallelisation of the revised simplex method for general large scale LP problems**

J. A. J. Hall

Contributed talk at Matrices in Statistics and Optimization: 18th October 2004**Parallelisation of the revised simplex method for general large scale LP problems**

J. A. J. Hall

Contributed talk at APMOD 04: 21st June 2004

### 2003

**Efficient global optimization: testing, reliability and efficiency**

J. A. J. Hall, K. I. M. McKinnon and T. Mayer

Invited seminar at Université Paul Sabatier: 14th October 2003**Hyper-sparsity in the revised simplex method and how to exploit it**

J. A. J. Hall and K. I. M. McKinnon

Invited seminar at CERFACS: 9th October 2003**Hyper-sparsity in the revised simplex method and how to exploit it**

J. A. J. Hall and K. I. M. McKinnon

Contributed talk at the Dundee Numerical Analysis Conference: 25th June 2003**Efficient global optimization: refinements and extensions**

J. A. J. Hall, K. I. M. McKinnon and T. Mayer

Invited seminar at the School of Mathematics of Cardiff University: 26th February 2003