iccsa-19-vtestbed

git clone https://git.igankevich.com/iccsa-19-vtestbed.git
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commit 464f90387c370a0249f34598594fc33fcee8ccdb
parent e053b723cdc2ef42f1ed4cdbd86001c674c7bde4
Author: Ivan Gankevich <igankevich@ya.ru>
Date:   Sat, 30 Mar 2019 13:33:51 +0300

Spell-check.

Diffstat:
main.tex | 14+++++++-------
references.bib | 2+-
2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/main.tex b/main.tex @@ -377,7 +377,7 @@ choose single precision in all benchmarks. \end{table} Double precision was used only for computing autoregressive model coefficients, -because roundoff and truncation numerical errors make covariance matrices (from +because round-off and truncation numerical errors make covariance matrices (from which coefficients are computed) non-positive definite. These matrices typically have very large condition numbers, and linear system which they represent cannot be solved by Gaussian elimination or \(LDLT\) Cholesky @@ -587,7 +587,7 @@ pressure is computed. These routines are much more compute intensive in comparison to wetted surface determination and pressure force computation (performance of which depends on the number of panels). -Despite the fact that Capybara has the highest floating-point performanace +Despite the fact that Capybara has the highest floating-point performance across all workstations in the benchmarks, Virtual testbed runs faster on its processor, not the graphical accelerator. Routine-by-routine investigation showed that it simply slower at computing even fully parallel Stokes wave @@ -617,17 +617,17 @@ both a processor and a graphical accelerator) is similar to approach followed by the authors of Spark distributed data processing framework~\cite{zaharia2016spark}. In this framework data is first loaded into the main memory of each cluster node and then processed in a loop. Each -iteration of this loop runs by all nodes in parallel and syncrhonisation occurrs +iteration of this loop runs by all nodes in parallel and synchronisation occurs at the end of each iteration. This is in contrast to MapReduce framework~\cite{dean2008mapreduce} where after each iteration the data is written to stable storage and then read back into the main memory to continue -prcoessing. Not interacting with slow stable storage on every iteration allows +processing. Not interacting with slow stable storage on every iteration allows Spark to achieve an order of magnitude higher performance than Hadoop (open-source version of MapReduce) on iterative algorithms. On a heterogeneous node an analogue of stable storage, read/writes to which is -much slower than accesses to the main memory, is graphical acelerator memory. To -minimise interaction with this memory, we do not read intermeidate results of +much slower than accesses to the main memory, is graphical accelerator memory. To +minimise interaction with this memory, we do not read intermediate results of our computations from it, but reuse arrays that already reside there. (As a concrete example, we do not copy pressure field from a graphical accelerator, only the forces for each panel.) This allows us to eliminate expensive data @@ -659,7 +659,7 @@ Apart from that, the main direction of future research is creation of on-board intelligent system that would include Virtual testbed as an integral part for simulating and predicting physical phenomena. -\subsubsection*{Acknowledgments.} +\subsubsection*{Acknowledgements.} Research work is supported by Saint Petersburg State University (grant no.~26520170). diff --git a/references.bib b/references.bib @@ -94,7 +94,7 @@ } @Misc{ hull2010, - title = {Analytical ship hull shape construction, wave resistance + title = {Analytic ship hull shape construction, wave resistance calculations, theoretical blueprint feature curve calculations, and ship stability diagrams (in {Russian})}, author = {Vasily Khramushin},