Normalizing or not normalizing? An open question for floating-point arithmetic in embedded systems

Emerging embedded applications lack of a specific standard when they require floating-point arithmetic. In this situation they use the IEEE-754 standard or ad hoc variations of it. However, this standard was not designed for this purpose. This paper aims to open a debate to define a new extension of the standard to cover embedded applications. In this work, we only focus on the impact of not performing normalization. We show how eliminating the condition of normalized numbers, implementation costs can be dramatically reduced, at the expense of a moderate loss of accuracy. Several architectures to implement addition and multiplication for non-normalized numbers are proposed and analyzed. We show that a combined architecture (adder-multiplier) can halve the area and power consumption of its counterpart IEEE-754 architecture. This saving comes at the cost of reducing an average of about 10 dBs the Signal-to-Noise Ratio for the tested algorithms. We think these results should encourage researchers to perform further investigation in this issue.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Assessing patient satisfaction levels following endometrial ablations in the treatment of abnormal uterine bleeding to determine effectiveness

OBJECTIVE: The objective of this study was to evaluate outcomes for women following endometrial ablations due to abnormal uterine bleeding (AUB). These outcomes included patient-reported quality of life, satisfaction with the procedure, and treatment failure. Women experiencing heavy/regular bleeding were compared with women experiencing heavy/irregular bleeding. DESIGN: The study was designed as a prospective cohort study of women aged 18-55 years presenting to Women and Infants Hospital (WIH) in Providence, Rhode Island, for endometrial ablations due to AUB. Sixty-three participants in the study completed the Baseline Health Form, the Short Form-36 Health Survey (SF-36), and the Menstrual Bleeding Questionnaire (MBQ) upon enrollment. At the 3-month, 6-month, and 1-year follow-ups participants completed the SF-36 and the MBQ. RESULTS: Baseline responses from the participants who were undergoing endometrial ablation found that 95.2% of women (n = 60) identified their periods as being heavy. From the total participants, 60.3% of women (n = 38) indicated their periods as being irregular. The SF-36 total score results demonstrate women with heavy/irregular bleeding experienced a greater negative impact in their quality of life. When broken down to the physical component score (PCS) and the mental component score (MCS) this difference, between women with heavy/regular bleeding and women with heavy/irregular bleeding, was minimized. Results from the MBQ revealed that women with heavy/irregular menstrual bleeding experienced a greater negative impact on their quality of life compared with women with heavy/regular bleeding. DISCUSSION: Heavy bleeding is one of the defining factors in determining whether women seek further treatment for their menstrual bleeding, and when they do, they will usually attempt other therapies before pursuing surgery. The MBQ revealed a difference in quality of life between women with heavy/irregular bleeding and women with heavy/regular bleeding because this questionnaire measures bleeding and its impact on a woman’s life. The SF-36 total scores also showed a difference between heavy/irregular bleeding and heavy/regular bleeding. Breaking down the total SF-36 total score into the PCS and MCS minimized this difference. This questionnaire focused more on overall general health rather than bleeding and this focus may account for the smaller scoring differences among bleeding patterns. CONCLUSION: Similar proportions of women experiencing heavy/regular and heavy/irregular bleeding pursue endometrial ablations as a treatment for AUB. The SF-36 demonstrated a greater burden on women’s general health when they have heavy/irregular bleeding. The MBQ provides a better measure to compare both bleeding patterns, aspects of bleeding, and demonstrates a more negative impact on quality of life for women with heavy/irregular bleeding

Unbiased Rounding for HUB Floating-point Addition

Copyright (c) 2018 IEEE doi:10.1109/TC.2018.2807429Half-Unit-Biased (HUB) is an emerging format based on shifting the represented numbers by half Unit in the Last Place. This format simplifies two’s complement and roundto- nearest operations by preventing any carry propagation. This saves power consumption, time and area. Taking into account that the IEEE floating-point standard uses an unbiased rounding as the default mode, this feature is also desirable for HUB approaches. In this paper, we study the unbiased rounding for HUB floating-point addition in both as standalone operation and within FMA. We show two different alternatives to eliminate the bias when rounding the sum results, either partially or totally. We also present an error analysis and the implementation results of the proposed architectures to help the designers to decide what their best option are.TIN2013-42253-P, TIN2016-80920-R, JA2012P12-TIC-169

Fast HUB Floating-point Adder for FPGA

Several previous publications have shown the area and delay reduction when implementing real number computation using HUB formats for both floating-point and fixed-point. In this paper, we present a HUB floating-point adder for FPGA which greatly improves the speed of previous proposed HUB designs for these devices. Our architecture is based on the double path technique which reduces the execution time since each path works in parallel. We also deal with the implementation of unbiased rounding in the proposed adder. Experimental results are presented showing the goodness of the new HUB adder for FPGA.TIN2016- 80920-R, JA2012 P12-TIC-1692, JA2012 P12-TIC-147

Boosting Backward Search Throughput for FM-Index Using a Compressed Encoding

The rapid development of DNA sequencing technologies has demanded for com- pressed data structures supporting fast pattern matching queries. FM-index is a widely-used compressed data structure that also supports fast pattern matching queries. It is common for the exact matching algorithm to be memory bound, resulting in poor performance. Searching several symbols in a single step improves data locality, although the memory bandwidth requirements remains the same. We propose a new data-layout of FM-index, called Split bit-vector, that compacts all data needed to search k symbols in a single step (k-step), reducing both memory movement and computing requirements at the cost of increasing memory footprint.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Representation Dimension of Cluster Concealed Algebras

We are going to show that the representation dimension of a cluster-concealed algebra B is 3. We compute its representation dimension by showing an explicit Auslander generator for the cluster-tilted algebra.Comment: 15 page