@article{le_kim_aspnes_2020, title={Quantitative assessment of linear noise-reduction filters for spectroscopy}, volume={28}, ISSN={["1094-4087"]}, DOI={10.1364/OE.411768}, abstractNote={Linear noise-reduction filters used in spectroscopy must strike a balance between reducing noise and preserving lineshapes, the two conflicting requirements of interest. Here, we quantify this tradeoff by capitalizing on Parseval’s Theorem to cast two measures of performance, mean-square error (MSE) and noise, into reciprocal- (Fourier-) space (RS). The resulting expressions are simpler and more informative than those based in direct- (spectral-) space (DS). These results provide quantitative insight not only into the effectiveness of different linear filters, but also information as to how they can be improved. Surprisingly, the rectangular (“ideal” or “brick wall”) filter is found to be nearly optimal, a consequence of eliminating distortion in low-order Fourier coefficients where the major fraction of spectral information is contained. Using the information provided by the RS version of MSE, we develop a version that is demonstrably superior to the brick-wall and also the Gauss-Hermite filter, its former nearest competitor.}, number={26}, journal={OPTICS EXPRESS}, author={Le, Long V and Kim, Young D. and Aspnes, David E.}, year={2020}, month={Dec}, pages={38917–38933} }
 @article{ha_le_rhee_xu_2007, title={Impact of background traffic on performance of high-speed TCP variant protocols}, volume={51}, DOI={10.1016/j.comnet.2006.11.005}, abstractNote={This paper examines the effect of background traffic on the performance of existing high-speed TCP variant protocols, namely BIC-TCP, CUBIC, FAST, HSTCP, H-TCP and Scalable TCP. We demonstrate that the stability, link utilization, convergence speed and fairness of the protocols are clearly affected by the variability of flow sizes and round-trip times (RTTs), and the amount of background flows competing with high-speed flows in a bottleneck router. Our findings include: (1) the presence of background traffic with variable flow sizes and RTTs improves the fairness of most high-speed protocols, (2) all protocols except FAST and HSTCP show good intra-protocol fairness regardless of the types of background traffic, (3) HSTCP needs a larger amount of background traffic and more variable traffic than the other protocols to achieve convergence, (4) H-TCP trades stability for fairness; that is, while its fairness is good independent of background traffic types, larger variance in the flow sizes and RTTs of background flows causes the protocol to induce a higher degree of global loss synchronization among competing flows, lowering link utilization and stability, (5) FAST suffers unfairness and instability in small buffer or long delay networks regardless of background traffic types, and (6) the fairness of high-speed protocols depends more on the amount of competing background traffic rather than its rate variability. We also find that the presence of high-speed flows does not greatly reduce the bandwidth usage of background Web traffic.}, number={7}, journal={Computer Networks (Amsterdam, Netherlands : 1999)}, author={Ha, S. T. and Le, L. and Rhee, I. and Xu, L. S.}, year={2007}, pages={1748–1762} }