Improving service level agreements for a job scheduler by visualizing simulations

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (p. 49-51).Currently, job owners at Google do not have a good way to generate suitable Service Level Agreements (SLAs), which means that they cannot accurately communicate their intentions to the job scheduler. This means that the owner's job might not finish on time or at all. The solution described in this thesis helps users visualize design changes to SLAs and use simulation to explore the behavior resulting from the SLAs. I have designed and begun development of a visualization and simulation framework that allows users to see how the job scheduler's behavior might vary under different SLA parameters. This thesis describes the steps made towards designing and implementing a system that both helps users visualize SLAs and their reward functions, and allows users to create an SLA and gain an idea of the behavior of a job scheduler with the SLA as input.by Dina M. Betser.M.Eng

Grid-Enabling a Vibroacoustic Analysis Application

This paper describes the process of grid-enabling a vibroacoustic analysis application using the Globus Toolkit 3.2.1. This is the first step in a project intended to grid-enable a suite of tools being developed as a service-oriented architecture for spacecraft telemetry analysis. Many of the applications in the suite are compute intensive and would benefit from significantly improved performance. In this paper we show the advantage of using Globus to grid-enable a single tool in a vibroacoustic analysis flow, with the result that using as few as eleven nodes, that tool’s runtime improved by a factor of eight. While communication overhead does affect performance, these results also indicate that coordinated communication and execution scheduling as part of workflow management would be able to significantly improve overall efficiency. In the larger context, our experience also shows that the service-oriented architecture approach, using grid computing tools, can provide a more flexible system design, in addition to improved performance and increased utilization of resources. We also provide some lessons learned in using the Globus Toolkit

Impact of targeted scanning protocols on perinatal outcomes in pregnancies at risk of placenta accreta spectrum or vasa previa

Background Placenta accreta spectrum and vasa previa (VP) are congenital disorders of placentation associated with high morbidity and mortality for both mothers and newborns when undiagnosed before delivery. Prenatal diagnosis of these conditions is essential to allow multidisciplinary management and thus improve perinatal outcomes. Objective The objective of the study was to compare perinatal outcome in women with placenta accreta spectrum or vasa previa before and after implementation of targeted scanning protocols. Study Design This retrospective study included 2 nonconcurrent cohorts for each condition before and after implementation of the corresponding protocols (2004–1012 vs 2013–2016 for placenta accreta spectrum and 1988–2007 vs 2008–2016 for vasa previa). Clinical reports of women diagnosed with placenta accreta spectrum and vasa previa during the study periods were reviewed and outcomes were compared. Results In total, there were 97 cases of placenta accreta spectrum and 51 cases with vasa previa, all confirmed at delivery. In both cohorts, the prenatal detection rate increased after implementation of the scanning protocols (28 of 65 cases [43.1%] vs 31 of 32 cases [96.9%], P < .001, for placenta accreta spectrum and 9 of 18 cases [50%] vs 29 of 33 cases [87.9%], 87.9%, P < .01 for vasa previa). The perinatal outcome improved also significantly in both cohorts after implementation of the protocols. In the placenta accreta spectrum cohort, the estimated blood loss and the postoperative hospitalization stay decreased between periods (1520 ± 845 vs 1168 ± 707 mL, P < .01, and 10.9 ± 14.1 vs 5.7 ± 2.2 days, P < .05, respectively). In the vasa previa cohort, the number of 5 minute Apgar score ≤5 and umbilical cord pH <7 decreased between periods (5 of 18 cases [27.8%] vs 1 of 33 cases [3%]; P < .05, and 4 of 18 cases [22.2%] vs 1 of 33 cases [3%], P < .05, respectively). Conclusion The implementation of standardized prenatal targeted scanning protocols for pregnant women with risk factors for placenta accreta spectrum and vasa previa was associated with improved maternal and neonatal outcomes. The continuous increases in the rates of caesarean deliveries and use of assisted reproductive technology highlights the need to develop training programs and introduce targeted scanning protocols at the national and international levels

Multiple events tracking in sound tracks

Detecting and tracking broad sound classes in audio documents is an important step toward structuration. In the case of complex audio scenes, such as TV broadcast sound tracks, one problem is that several audio events may occur simultaneously. In this paper, we propose a two-step approach to detect superimposed events. The first step is a blind segmentation step, followed by an event detection step on each segment. In order to better evaluate the quality of the system, new performance measures have been introduced, more suited to the superimposed events detection task. We also extend the two-step approach with an equivalent Viterbi-based event detection approach. 1

Submicron lateral scaling of HBTs and other vertical-transport devices:towards THz bandwidths

With appropriate device structures, bined lithographi and epitaxial scaling of HBTs,RTDs and S hottky diodes results in rapid in reases in device bandwidths.0.1 ¹m InGaAs RTDs have os illated at 650 GHz,Submi ron heterojunction bipolar sistors (HBTs)fabri ated with substrate transfer pro-esses have obtained 21 dB unilateral power gain at 100 GHz;if extrapolated at -20 dB/decade,this corresponds to a 1.1 THz power-gain uto ®frequency.HBT current-gain uto ®frequencies as high as 300 GHz have been obtained

Extraction of information from video sound tracks - can we detect simultaneous events

Detecting and tracking broad sound classes in audio documents is an important step toward their structuration. In the case of complex audio scenes, such as the sound track of a TV broadcast, one problem is that several classes of sound maybe present simultaneously. It is therefore important to detect such superimposed events. Most methods would necessitate to estimate a model for each combination of sound classes that is to be detected, which is intractable in practice since it requires a lot of manual labelling. In this paper, we propose and compare several approaches to detect simultaneous events using only the models of the base classes we are interested in. Two main approaches are compared: model combination and binary hypothesis tests. The results show that the best results are obtained with the model combination approach. 1

Tennis video abstraction from audio and visual cues

We propose a context-based model of video abstraction exploiting both audio and video features and applied to tennis TV programs. We can automatically produce different types of summary of a given video depending on the users&apos; constraints or preferences. We have first designed an efficient and accurate temporal segmentation of the video into segments homogeneous w.r.t. the camera motion. We introduce original visual descriptors related to the dominant and residual image motions. The different summary types are obtained by specifying adapted classification criteria which involve audio features to select the relevant segments to be included in the video abstract. The proposed scheme has been validated on 22 hours of tennis videos

Impact of the COVID-19 Pandemic on Excess Perinatal Mortality and Morbidity in Israel

OBJECTIVE:  The 2020 COVID-19 pandemic has been associated with excess mortality and morbidity in adults and teenagers over 14 years of age, but there is still limited evidence on the direct and indirect impact of the pandemic on pregnancy. We aimed to evaluate the effect of the first wave of the COVID-19 pandemic on obstetrical emergency attendance in a low-risk population and the corresponding perinatal outcomes. STUDY DESIGN:  This is a single center retrospective cohort study of all singleton births between February 21 and April 30. Prenatal emergency labor ward admission numbers and obstetric outcomes during the peak of the first COVID-19 pandemic of 2020 in Israel were compared with the combined corresponding periods for the years 2017 to 2019. RESULTS:  During the 2020 COVID-19 pandemic, the mean number of prenatal emergency labor ward admissions was lower, both by daily count and per woman, in comparison to the combined matching periods in 2017, 2018, and 2019 (48.6 ± 12.2 vs. 57.8 ± 14.4, p 40 and 41 weeks, mode of delivery, and numbers of emergency cesarean deliveries were similar in both groups. There was no difference in the intrapartum fetal death rate between the groups. CONCLUSION:  The COVID-19 pandemic stay-at-home policy combined with patient fear of contracting the disease in hospital could explain the associated higher rate of stillbirth. This collateral perinatal damage follows a decreased in prenatal emergency labor ward admissions during the first wave of COVID-19 in Israel. KEY POINTS: · Less obstetrical ER attendance is observed during the pandemic.. · There is a parallel increase in stillbirth rate.. · Stillbirth cases tested negative for COVID-19.. · Lockdown and pandemic panic are possible causes.