Predicting Software Suitability Using a Bayesian Belief Network

The ability to reliably predict the end quality of software under development presents a significant advantage for a development team. It provides an opportunity to address high risk components earlier in the development life cycle, when their impact is minimized. This research proposes a model that captures the evolution of the quality of a software product, and provides reliable forecasts of the end quality of the software being developed in terms of product suitability. Development team skill, software process maturity, and software problem complexity are hypothesized as driving factors of software product quality. The cause-effect relationships between these factors and the elements of software suitability are modeled using Bayesian Belief Networks, a machine learning method. This research presents a Bayesian Network for software quality, and the techniques used to quantify the factors that influence and represent software quality. The developed model is found to be effective in predicting the end product quality of small-scale software development efforts

Imaging Modality and Frequency in Surveillance of Stage I Seminoma Testicular Cancer: Results From a Randomized, Phase III, Noninferiority Trial (TRISST)

PURPOSE: Survival in stage I seminoma is almost 100%. Computed tomography (CT) surveillance is an international standard of care, avoiding adjuvant therapy. In this young population, minimizing irradiation is vital. The Trial of Imaging and Surveillance in Seminoma Testis (TRISST) assessed whether magnetic resonance images (MRIs) or a reduced scan schedule could be used without an unacceptable increase in advanced relapses. METHODS: A phase III, noninferiority, factorial trial. Eligible participants had undergone orchiectomy for stage I seminoma with no adjuvant therapy planned. Random assignment was to seven CTs (6, 12, 18, 24, 36, 48, and 60 months); seven MRIs (same schedule); three CTs (6, 18, and 36 months); or three MRIs. The primary outcome was 6-year incidence of Royal Marsden Hospital stage ≥ IIC relapse (> 5 cm), aiming to exclude increases ≥ 5.7% (from 5.7% to 11.4%) with MRI (v CT) or three scans (v 7); target N = 660, all contributing to both comparisons. Secondary outcomes include relapse ≥ 3 cm, disease-free survival, and overall survival. Intention-to-treat and per-protocol analyses were performed. RESULTS: Six hundred sixty-nine patients enrolled (35 UK centers, 2008-2014); mean tumor size was 2.9 cm, and 358 (54%) were low risk (< 4 cm, no rete testis invasion). With a median follow-up of 72 months, 82 (12%) relapsed. Stage ≥ IIC relapse was rare (10 events). Although statistically noninferior, more events occurred with three scans (nine, 2.8%) versus seven scans (one, 0.3%): 2.5% absolute increase, 90% CI (1.0 to 4.1). Only 4/9 could have potentially been detected earlier with seven scans. Noninferiority of MRI versus CT was also shown; fewer events occurred with MRI (two [0.6%] v eight [2.6%]), 1.9% decrease (-3.5 to -0.3). Per-protocol analyses confirmed noninferiority. Five-year survival was 99%, with no tumor-related deaths. CONCLUSION: Surveillance is a safe management approach-advanced relapse is rare, salvage treatment successful, and outcomes excellent, regardless of imaging frequency or modality. MRI can be recommended to reduce irradiation; and no adverse impact on long-term outcomes was seen with a reduced schedule

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Design Of An Integrated Feature And Terrain Triangulation Algorithm For Driving Simulation Terrain Database Generation: Final Report To The Center For Advanced Transportation Systems Simulation

Report on two surface simplification algorithms designed for the purpose of constructing a terrain database that is optimized for driving simulation

A Comparison Of Software Quality Modeling Techniques

Accurately representing the quality of software under development remains a major challenge to the software engineering discipline. Many approaches have been offered that attempt to capture the complex relationships between metrics captured during design, and the final quality of the software product Unfortunately, most of these approaches are either controversial in terms of their validity or simply not universally applicable. This study compares the effectiveness of three different estimation techniques: least square regression, relative least squares regression, and the iterative averaging algorithm. Using the average relative error criterion, it is the iterative averaging algorithm, a very simple method of spatial data analysis, that is revealed to be superior in terms its ability to correctly represent a given data set, and its ability to provide accurate and valid predictions about whether or not a given software module will be error-prone

Fdtd Speedups Obtained In Distributed Computing On A Linux Workstation Cluster

Various aspects of the finite-difference time-domain (FDTD) implementation on a workstation cluster were studied. The computation grid was divided among nodes. The MPI parallel implementation was integrated with POSIX threads because each node in the cluster was equipped with two processors. On each node, each process contained two threads that executed in parallel. As expected, for sufficiently large problems the speedup was increased by almost a factor of two when using threads

Two Surface Simplification Algorithms For Polygonal Terrain With Integrated Road Features

Terrain database generation is one of the most expensive tasks in the development of human-in-the-loop visual simulations. There are many factors associated with the efficiency of generating the terrain database. Automating the process of extracting from remote sensing imagery the required database primitives, and constructing detailed 3D feature models offers many challenging problems. Another problem is to simplify the terrain model by using fewer polygons without significant loss in the visual characteristics of the rendered imagery, thereby reducing the complexity of the terrain database and improving real-time rendering performance. In this paper we present two surface simplification algorithms designed for the purpose of constructing a terrain database that is optimized for driving simulation; one using a bottom-up, polygonal refinement approach, the other using a top-down, polygonal removal approach. These two algorithms are applied to terrain surfaces that include integrated, `stitched-in\u27 road features, and are used to generate terrain surfaces of various levels of detail. We provide a discussion on the design of these two algorithms, some experimental results of applying the algorithms to real terrain surfaces, as well as the comparison of the two approaches on the factors of height error and the distance from the road

Preliminary Investigations Into Distributed Computing Applications On A Beowulf Cluster

In this paper we examine various modeling and simulation applications of cluster computing using a Beowulf cluster. These applications are used to investigate the performance of our cluster in terms of computational speedup, scalability, and communications. The applications include solution of linear systems by Jacobi iteration, distributed image generation, and the finite difference time domain solution of Maxwell\u27s equations. It is observed that the computational load for these applications must be large compared to the communication overhead to take advantage of the speedup obtained using parallel computing. For the applications reviewed here, this condition is increasingly satisfied as the problem size becomes larger or as higher resolution is required

Analysis Of Ultra-Wide Band Signal Propagation In An Indoor Environment

Ultra-wide band signal propagation in an urban environment is measured and studied. The basic concept is to develop, transmit and receive an extremely short duration burst of radio frequency energy-typically a few tens of pico seconds to a few nanoseconds in duration. The resultant waveforms are extremely broadband, so much so that it is often difficult to determine an actual RF center frequency-thus the term carrier-free [1]. In this paper, the indoor propagation of UWB signals inside an office room is studied. A simulation model of this system is compared with the actual test results