We propose a fast algorithm for ridge regression when the number of features is much larger than the number of observations (p n). The standard way to solve ridge regression in this setting works in the dual space and gives a running time of O(np). Our algorithm Subsampled Randomized Hadamard TransformDual Ridge Regression (SRHT-DRR) runs in time O(np log(n)) and works by preconditioning the de...

The task of dimensionality reduction for regression (DRR) is to find a low dimensional representation z ∈ R of the input covariates x ∈ R, with q p, for regressing the output y ∈ R. DRR can be beneficial for visualization of high dimensional data, efficient regressor design with a reduced input dimension, but also when eliminating noise in data x through uncovering the essential information z f...

The aim of our study was to develop an algorithm to simulate the digitally reconstructed radiograph (DRR) calculation process for different beam qualities (photon energies) in the range 50 keV to 12 MeV. This was achieved using volumetric anatomical data for the patient obtained from three-dimensional diagnostic CT images. These DRR images can be used in three-dimensional treatment planning for...

The paper presents a modified version of the deficit round-robin (DRR) scheduling algorithm due to [1]. The proposed scheduling scheme called Weighted Switch Deficit Round Robin (WSDRR) categorises the different frame types of compressed video which are handled in separate queues and prioritizes time-sensitive and visually important data. WSDRR also introduces an overdraft threshold that basica...

Deficit Round Robin (DRR) is a scheduling algorithm which provides fair queuing at O(1) complexity. However, due to its round robin structure, its latency properties are not adequate for latency-critical applications, such as voice. For this reason, router manufacturers implement variants of the DRR algorithm which guarantee lower latencies to one (or a subset of) queue(s). In this paper we eva...

We present a novel scheme for uplink scheduling in WiMax networks that attempts to balance worst-case fairness in bandwidth allocation with the delay requirements of traffic, while taking the varying nature of the wireless channel into account. We assume a polling-based mode of operation at the base station ( ), and provide a method of obtaining an optimal polling interval at which the should p...

Deficit Round Robin (DRR) and Weighted Deficit Round Robin schedulers have shown their ability in providing fair and weighted sharing of network resources for network devices. However, they are unable to provide fairness in terms of waiting time of packets among flows. We propose a new packet scheduling discipline, Weighted Deficit Earliest Departure First scheduler. It provides fairness in ter...

Microphone arrays and beamforming have been used extensively for speech and audio acquisition in noisy and reverberant environments. In this paper, our objective is to investigate analytically the dereverberation performance of a beamformer. As an evaluation metric we apply the commonly used direct-toreverberant ratio (DRR). Consequently, we utilize tools from statistical room acoustic theory t...

We examine the problem of reliable workflow scheduling with less resource redundancy. As scheduling workflow applications in heterogeneous systems, either for optimizing the reliability or for minimizing the makespan, are NP-Complete problems, we alternatively find schedules for meeting specific reliability and deadline requirements. First, we analyze the reliability of a given schedule using t...

This paper analyses the perceptions of disaster risk reduction (DRR) practitioners concerning the on-going integration of climate change adaptation (CCA) into their practices in urban contexts in Nicaragua. Understanding their perceptions is important as this will provide information on how this integration can be improved. Exploring the perceptions of practitioners in Nicaragua is important as...