A Study of Deep Learning Robustness Against Computation Failures

For many types of integrated circuits, accepting larger failure rates in computations can be used to improve energy efficiency. We study the performance of faulty implementations of certain deep neural networks based on pessimistic and optimistic models of the effect of hardware faults. After identifying the impact of hyperparameters such as the number of layers on robustness, we study the ability of the network to compensate for computational failures through an increase of the network size. We show that some networks can achieve equivalent performance under faulty implementations, and quantify the required increase in computational complexity

Modeling and Energy Optimization of LDPC Decoder Circuits with Timing Violations

This paper proposes a "quasi-synchronous" design approach for signal processing circuits, in which timing violations are permitted, but without the need for a hardware compensation mechanism. The case of a low-density parity-check (LDPC) decoder is studied, and a method for accurately modeling the effect of timing violations at a high level of abstraction is presented. The error-correction performance of code ensembles is then evaluated using density evolution while taking into account the effect of timing faults. Following this, several quasi-synchronous LDPC decoder circuits based on the offset min-sum algorithm are optimized, providing a 23%-40% reduction in energy consumption or energy-delay product, while achieving the same performance and occupying the same area as conventional synchronous circuits.Comment: To appear in IEEE Transactions on Communication

On the time to tracer equilibrium in the global ocean

An important issue for the interpretation of data from deep-sea cores is the time for tracers to be transported from the sea surface to the deep ocean. Global ocean circulation models can help shed light on the timescales over which a tracer comes to equilibrium in different regions of the ocean. In this note, we discuss how the most slowly decaying eigenmode of a model can be used to obtain a relevant timescale for a tracer that enters through the sea surface to become well mixed in the ocean interior. We show how this timescale depends critically on the choice between a Neumann surface boundary condition in which the flux of tracer is prescribed, a Robin surface boundary condition in which a combination of the flux and tracer concentration is prescribed or a Dirichlet surface boundary condition in which the concentration is prescribed. Explicit calculations with a 3-box model and a three-dimensional ocean circulation model show that the Dirichlet boundary condition when applied to only part of the surface ocean greatly overestimate the time needed to reach equilibrium. As a result regional-"injection" calculations which prescribe the surface concentration instead of the surface flux are not relevant for interpreting the regional disequilibrium between the Atlantic and Pacific found in paleo-tracer records from deep-sea cores. For tracers that enter the ocean through air-sea gas exchange a prescribed concentration boundary condition can be used to infer relevant timescales if the air-sea gas exchange rate is sufficiently fast, but the boundary condition must be applied over the entire ocean surface and not only to a patch of limited area. For tracers with a slow air-sea exchange rate such as 14C a Robin-type boundary condition is more relevant and for tracers such as d18O that enter the ocean from melt water, a Neumann boundary condition is presumably more relevant. Our three-dimensional model results based on a steady-state modern circulation suggest that the relative disequilibrium between the deep Atlantic and Pacific is on the order of "only" 1200 years or less for a Neumann boundary condition and does not depend on the size and location of the patch where the tracer is injected

Stall Pattern Avoidance in Polynomial Product Codes

Product codes are a concatenated error-correction scheme that has been often considered for applications requiring very low bit-error rates, which demand that the error floor be decreased as much as possible. In this work, we consider product codes constructed from polynomial algebraic codes, and propose a novel low-complexity post-processing technique that is able to improve the error-correction performance by orders of magnitude. We provide lower bounds for the error rate achievable under post processing, and present simulation results indicating that these bounds are tight.Comment: 4 pages, 2 figures, GlobalSiP 201

Development of a Prehabilitation Multimodal Supportive Care Interventions for Men and Their Partners Before Radical Prostatectomy for Localized Prostate Cancer

Background: An important question revolves around when the most opportune time is to introduce recovery-optimizing behaviors for men opting for radical prostatectomy (RP) for localized prostate cancer (PCa). An emerging field of research describes the role of pre-operative strategies to improve treatment tolerance, and overall physical and psychological recovery. Objective: To explore the perceptions of a multimodal pre-habilitation intervention for men and their partners prior to RP for localized PCa. Intervention/Methods: Thirty-four patients who opted for RP for localized PCa and their partners (19) were identified and recruited into the study. The multimodal intervention comprised of educational materials, physiotherapy instruction and a self-management group-based seminar. Results: The multimodal pre-habilitation intervention was perceived as overall helpful with demonstrated acceptability (91.9%). Beneficial themes related to the quality of the information provided to support self-management, open forum questions with multidisciplinary healthcare professionals, and increased knowledge among partners to help with their understanding of how to look after their husbands. Conclusion: The intervention was feasible and beneficial for the prostate cancer dyad. A future pilot RCT study is needed to provide sufficient evidence on the long-term physical and psychological outcomes and cost-effectiveness. Implications for Practice: Oncology nurses play a key role in the development of pre-habilitation care delivery. Pre-habilitation interventions can have a positive effect on improving health outcomes for cancer patients and their partners after surgery and into survivorship

Northwestern Pacific typhoon intensity controlled by changes in ocean temperatures.

Dominant climatic factors controlling the lifetime peak intensity of typhoons are determined from six decades of Pacific typhoon data. We find that upper ocean temperatures in the low-latitude northwestern Pacific (LLNWP) and sea surface temperatures in the central equatorial Pacific control the seasonal average lifetime peak intensity by setting the rate and duration of typhoon intensification, respectively. An anomalously strong LLNWP upper ocean warming has favored increased intensification rates and led to unprecedentedly high average typhoon intensity during the recent global warming hiatus period, despite a reduction in intensification duration tied to the central equatorial Pacific surface cooling. Continued LLNWP upper ocean warming as predicted under a moderate [that is, Representative Concentration Pathway (RCP) 4.5] climate change scenario is expected to further increase the average typhoon intensity by an additional 14% by 2100

A pilot randomised controlled trial of a multimodal supportive care (ThriverCare) intervention for managing unmet supportive care needs in men with metastatic prostate cancer on hormonal treatment and their partner/caregivers

Purpose: Men with metastatic prostate cancer experience high levels of unmet supportive care needs in current healthcare delivery. We set out to determine the effectiveness of a multimodality supportive care (ThriverCare) intervention on the prevalence of unmet supportive care needs for men and their partner/caregivers. Methods: A prospective parallel group, pilot randomised controlled pilot trial in 4 hospitals in Scotland. 38 participants with radiologically proven metastatic prostate cancer disease and 10 partners/caregivers were recruited into the study. A two arm 1:1 study design compared the usual standard of care (SC) approach to SC plus ThriverCare intervention. The primary outcome was the Supportive Care Needs Survey at 3 months of intervention. Results: There was no statistical significant difference in the prevalence of unmet supportive care needs between the intervention group and the usual SC group at baseline p=0.112, however a statistically significant difference was observed at 3 months, indicating that the prevalence of unmet supportive care needs were less in the intervention group (1.13, SD 2.5) compared to the usual SC (6.17, SD 7.05), p=0.002. This document includes supplementary information of "A prostate cancer gude to thriveship: Men, it's time to thirve", which can be found at the end of the article. Conclusion: ThriverCare appears to improve the supportive care experience of men with metastatic prostate cancer on hormonal treatment and their partner/caregivers. Our results accentuate that no longer one size of care delivery fits all, care must be responsive and adaptable to meet the individual needs of people affected by cancer to thrive