DATAWorks Sessions Archive

Equipment Failure Reports (EFRs) describe equipment failures and the steps taken as a result of these failures. EFRs contain both structured and unstructured data. Currently, analysts manually read through EFRs to understand failure modes and make recommendations to reduce future failures. This is a tedious process where important trends and information can get lost. This motivated the creation of an interactive dashboard that extracts relevant information from the unstructured (i.e. free-form text) data and combines it with structured data like failure date, corrective action and part number. The dashboard is an RShiny application that utilizes numerous text mining and visualization packages, including tm, plotly, edgebundler, and topicmodels. It allows the end-user to filter to the EFRs that they care about and visualize meta-data, such as geographic region where the failure occurred, over time allowing previously unknown trends to be seen. The dashboard also applies topic modeling to the unstructured data to identify key themes. Analysts are now able to quickly identify frequent failure modes and look at time and region-based trends in these common equipment failures.

The use of statistically rigorous methods to support testing at Arnold Engineering Development Complex (AEDC) has been an area of focus in recent years. As part of this effort, the use of Design of Experiments (DOE) has been introduced for calibration of AEDC wind tunnels. Historical calibration efforts used One- Factor-at-a-Time (OFAT) test matrices, with a concentration on conditions of interest to test customers. With the introduction of DOE, the number of test points collected during the calibration decreased, and were not necessary located at historical calibration points. To validate the use of DOE for calibration purposes, the 4-ft Aerodynamic Wind Tunnel 4T was calibrated using both DOE and OFAT methods. The results from the OFAT calibration were compared to model developed from the DOE data points and it was determined that the DOE model sufficiently captured the tunnel behavior within the desired levels of uncertainty. DOE analysis also showed that within Tunnel 4T, systematic errors are insignificant as indicated by agreement noted between the two methods. Based on the results of this calibration, a decision was made to apply DOE methods to future tunnel calibrations, as appropriate. The development of the DOE matrix in Tunnel 4T required the consideration of operational limitations, measurement uncertainties, and differing tunnel behavior over the performance map. Traditional OFAT methods allowed tunnel operators to set conditions efficiently while minimizing time consuming plant configuration changes. DOE methods, however, require the use of randomization which had the potential to add significant operation time to the calibration. Additionally, certain tunnel parameters, such as variable porosity, are only of interest in a specific region of the performance map. In addition to operational concerns, measurement uncertainty was an important consideration for the DOE matrix. At low tunnel total pressures, the uncertainty in the Mach number measurements increase significantly. Aside from introducing non-constant variance into the calibration model, the large uncertainties at low pressures can increase overall uncertainty in the calibration in high pressure regions where the uncertainty would otherwise be lower. At high pressures and transonic Mach numbers, low Mach number uncertainties are required to meet drag count uncertainty requirements. To satisfy both the operational and calibration requirements, the DOE matrix was divided into multiple independent models over the tunnel performance map. Following the Tunnel 4T calibration, AEDC calibrated the Propulsion Wind Tunnel 16T, Hypersonic Wind Tunnels B and C, and the National Full-Scale Aerodynamics Complex (NFAC). DOE techniques were successfully applied to the calibration of Tunnel B and NFAC, while a combination of DOE and OFAT test methods were used in Tunnel 16T because of operational and uncertainty requirements over a portion of the performance map. Tunnel C was calibrated using OFAT because of operational constraints. The cost of calibrating these tunnels has not been significantly reduced through the use of DOE, but the characterization of test condition uncertainties is firmly based in statistical methods.

Rigorous characterization of system capabilities is essential for defensible decisions in test and evaluation (T&E). Analysis of designed experiments is not usually associated “big” data analytics as there are typically a modest number of runs, factors, and responses. The Mars Rover program has recently conducted several disciplined DOEs on prototype coring drill performance with approximately 10 factors along with scores of responses and hundreds of recorded covariates. The goal is to characterize the ‘atthis-time’ capability to confirm what the scientists and engineers already know about the system, answer specific performance and quality questions across multiple environments, and inform future tests to optimize performance. A ‘rigorous’ characterization required that not just one analytical path should be taken, but a combination of interactive data visualization, classic DOE analysis screening methods, and newer methods from predictive analytics such as decision trees. With hundreds of response surface models across many test series and qualitative factors, these methods used had to efficiently find the signals hidden in the noise. Participants will be guided through an end-to-end analysis workflow with actual data from many tests (often Definitive Screening Designs) of the Rover prototype coring drill. We will show data assembly, data cleaning (e.g. missing values and outliers), data exploration with interactive graphical designs, variable screening, response partitioning, data tabulation, model building with stepwise and other methods, and model diagnostics. Software packages such as R and JMP will be used.

Resampling Methods: This tutorial presents widely used resampling methods to include bootstrapping, cross-validation, and permutation tests. Underlying theories will be presented briefly, but the primary focus will be on applications. A new graph-theoretic approach to change detection will be discussed as a specific application of permutation testing. Examples will be demonstrated in R; participants are encouraged to bring their own portable computers to follow along using datasets provided by the instructor.

Collaborative autonomous sensor networks have recently been used in many applications including inspection, law enforcement, search and rescue, and national security. They offer scalable, low cost solutions which are robust to the loss of multiple sensors in hostile or dangerous environments. While often comprised of less capable sensors, the performance of a large network can approach the performance of far more capable and expensive platforms if nodes are effectively coordinating their sensing actions and data processing. This talk will summarize work to date at LLNL on distributed signal processing and decentralized optimization algorithms for collaborative autonomous sensor networks, focusing on ADMM-based solutions for detection/estimation problems and sequential greedy optimization solutions which maximize submodular functions, e.g. mutual information.

This session will focus on the novel application of a design of experiments approach to optimize a propulsion charge configuration for a U.S. Army artillery round. The interdisciplinary design effort included contributions from subject matter experts in statistics, propulsion charge design, computational physics and experimentation. The process, which we will present in this session, consisted of an initial, low fidelity modeling and simulation study to reduce the parametric space by eliminating inactive variables and reducing the ranges of active variables for the final design. The final design used a multi-tiered approach that consolidated data from multiple sources including low fidelity modeling and simulation, high fidelity modeling and simulation and live test data from firings in a ballistic simulator. Specific challenges of the effort that will be addressed include: integrating data from multiple sources, a highly constrained design space, functional response data, multiple competing design objectives and real-world test constraints. The result of the effort is a final, optimized propulsion charge design that will be fabricated for live gun firing.

This case study highlights activities performed during the front-end process of a software development effort undertaken by the Fire Support Command and Control Program Office. This program office provides the U.S. Army, Joint and coalition commanders with the capability to plan, execute and deliver both lethal and non-lethal fires. Recently, the program office has undertaken modernization of its primary field artillery command and control system that has been in use for over 30 years. The focus of this case study is on the user-centered design process and activities taken prior to and immediately following contract award. A modified waterfall model comprised of three cyclic, yet overlapping phases (observation, visualization, and evaluation) provided structure for the iterative, user-centered design process. Gathering and analyzing data collected during focus groups, observational studies, and workflow process mapping, enabled the design team to identify 1) design patterns across the role/duty, unit and echelon matrix (a hierarchical organization structure), 2) opportunities to automate manual processes, 3) opportunities to increase efficiencies for fire mission processing, 4) bottlenecks and workarounds to be eliminated through design of the modernized system, 5) shortcuts that can be leveraged in design, 6) relevant and irrelevant content for each user population for streamlining access to functionality, 7) a usability baseline for later comparison (e.g., the number of steps and time taken to perform a task as captured in workflows for comparison to the same task in the modernized system), and provided the basis for creating visualizations using wireframes. Heuristic evaluations were conducted early to obtain initial feedback from users. In the next few months, usability studies will enable users to provide feedback based on actual interaction with the newly designed software. Included in this case study are descriptions of the methods used to collect user-centered design data, how results were visualized/documented for use by the development team, and lessons learned from applying user-centered design techniques during software development of a military field artillery command and control system.

The Boeing Company is assessing uncertainty quantification methodologies across many phases of aircraft design in order to establish confidence in computational fluid dynamics-based simulations of aircraft performance. This presentation provides an overview of several of these efforts. First, the uncertainty in aerodynamic performance metrics of a commercial aircraft at transonic cruise due to turbulence model and flight condition variability is assessed using 3D CFD with non-intrusive polynomial chaos and second order probability. Second, a sample computation of uncertainty in increments is performed for an engineering trade study, leading to the development of a new method for propagating input-uncontrolled uncertainties as well as input-controlled uncertainties. This type of consideration is necessary to account for variability associated with grid convergence on different configurations, for example. Finally, progress toward applying the computed uncertainties in forces and moments into an aerodynamic database used for flight simulation will be discussed. This approach uses a combination of Gaussian processes and multiple-fidelity Kriging meta-modeling to synthesize the required data.

Hardly a week goes by without news of a cybersecurity breach or an attack by cyber adversaries against a nation’s infrastructure. These incidents have wide-ranging effects, including reputational damage and lawsuits against corporations with poor data handling practices. Further, these attacks do not require the direction, support, or funding of technologically advanced nations; instead, significant damage can be – and has been – done with small teams, limited budgets, modest hardware, and open source software. Due to the significance of these threats, it is critical to analyze past events to predict trends and emerging threats. In this document, we present an implementation of a cybersecurity taxonomy and a methodology to characterize and analyze all stages of a cyberattack. The chosen taxonomy, MITRE ATT&CK™, allows for detailed definitions of aggressor actions which can be communicated, referenced, and shared uniformly throughout the cybersecurity community. We translate several open source cyberattack descriptions into the analysis framework, thereby constructing cyberattack data sets. These data sets (supplemented with notional defensive actions) illustrate example Red Team activities. The data collection procedure, when used during penetration testing and Red Teaming, provides valuable insights about the security posture of an organization, as well as the strengths and shortcomings of the network defenders. Further, these records can support past trends and future outlooks of the changing defensive capabilities of organizations. From these data, we are able to gather statistics on the timing of actions, detection rates, and cyberattack tool usage. Through analysis, we are able to identify trends in the results and compare the findings to prior events, different organizations, and various adversaries.

Goodness-of-fit (GOF) testing is used in many applications, including statistical hypothesis testing to determine if a set of data come from a hypothesized distribution. In addition, combined probability tests are extensively used in meta-analysis to combine results from several independent tests to asses an overall null hypothesis. This paper summarizes a study conducted to determine which GOF and/or combined probability test(s) can be used to determine if a set of data with relative small sample size comes from the standard uniform distribution, U(0,1). The power against different alternative hypothesis of several GOF tests and combined probability methods were examined. The GOF methods included: Anderson-Darling, Chi-Square, Kolmogorov-Smirnov, Cramér-Von Mises, Neyman-Barton, Dudewicz-van der Meulen, Sherman, Quesenberry-Miller, Frosini, and Hegazy-Green; while thecombined probability test methods included: Fisher’s Combined Probability Test, Mean Z, Mean P, Maximum P, Minimum P, Logit P, and Sum Z. While no one method was determined to provide the best power in all situations, several useful methods to support model validation were identified.

The Military Global Positioning System (GPS) User Equipment (MGUE) program is the user segment of the GPS Enterprise—a program on the Deputy Assistant Secretary of Defense for Developmental Test and Evaluation (DASD(DT&E)) Space and Missile Defense Systems portfolio. The MGUE program develops and test GPS cards capable of using Military-Code (M Code) and legacy signals. The program’s DT&E strategy is challenging. The GPS cards provide new, untested capabilities. Milestone A was approved on 2012 with sole source contracts released to three vendors for Increment 1. An Acquisition Decision Memorandum directs the program to support a Congressional Mandate to provide GPS M Code-capable equipment for use after FY17. Increment 1 provides GPS receiver form factors for the ground domain interface as well as for the aviation and maritime domain interface. When reviewing DASD(DT&E) Milestone B (MS B) Assessment Report, Mr. Kendall expressed curiosity about how the Developmental Evaluation Framework (DEF) and Design of Experiments (DOE) help. This presentation describes how the DEF and DOE methods help producing more informative and more economical developmental tests than what was originally under consideration by the test community—decision-quality information with a 60% reduction in test cycle time. It provides insight into how the integration of the DEF and DOE improved the overall effectiveness of the DT&E strategy, illustrates the role of modeling and simulation (M&S) in the test design process, provides examples of experiment designs for different functional and performance areas, and illustrates the logic involved in balancing risks and test resources. The DEF and DOE methods enables the DT&E strategy to fully exploit early discovery, to maximize verification and validation opportunities, and to characterize system behavior across the technical requirements space.

We created the Open Architectures Tradeoff (OAT) tool, a simple, computational game engine for rapidly exploring hypotheses about mission effectiveness in Battle Management Command and Control (BMC2). Each run of an OAT game simulates a military mission in contested airspace. Game objects represent U.S., adversary, and allied assets, each of which moves through the simulated airspace. Each U.S. asset has a Command and Control (C2) package the controls its actions—currently, neural networks form the basis of each U.S. asset’s C2 package. The weights of the neural network are randomized at the beginning of each game and are updated over the course of the game as the U.S. asset learns which of its actions lead to rewards, e.g., intercepting an adversary. Weights are updated via a Decentralized Partially Observable Markov Decision Process (Dec-POMDP) altered to accommodate a Reinforcement Learning paradigm. OAT allows a user to winnow down the trade space that should be considered when setting up more expensive and time-consuming campaign models. OAT could be used to weed out bad ideas for “fast failure”, thus avoiding waste of campaign modeling resources. Questions can be explored via OAT such as: Which combination of system capabilities is likely to be more or less effective in a particular military mission? For example, in an early analysis, OAT was used to test the hypothesis that increases in U.S. assets’ sensor range always lead to increases in mission effectiveness, quantified as the percent of adversaries intercepted. We ran over 2500 OAT games, each time varying the sensor range of U.S. assets and the density of adversary assets. Results show that increasing sensor range did lead to an increase in military effectiveness—but only up to a certain point. Once the sensor range surpassed approximately 10-15% of the simulated airspace size, no further gains were made in the percent of adversaries intercepted. Thus, campaign modelers should hesitate to devote resources to exploring sensor range in isolation. More recent OAT analyses are exploring more complex hypotheses regarding the trade space between sensor range and communications range.

Cybersecurity Metrics and Quantification is a fundamental but notoriously hard problem. It is one of the pillars underlying the emerging Science of Cybersecurity. In this talk, I will describe a number of cybersecurity metrics quantification research problems that are encountered in evaluating the effectiveness of a range of cyber defense tools. I will review the research results we have obtained over the past years. I will also discuss future research directions, including the ones that are undertaken in my research group.

Binary response experiments are common in epidemiology, biostatistics as well as in military applications. The Up and Down method, Langlie’s Method, Neyer’s method, K in a Row method and 3 Phase Optimal Design are methods used for sequential experimental design when there is a single continuous variable and a binary response. During this talk, we will discuss a new sequential experimental design approach called the Break Separation Method (BSM). BSM provides an algorithm for determining sequential experimental trials that will be used to find a median quantile and fit a logistic regression model using Maximum Likelihood estimation. BSM results in a small sample size and is designed to efficiently compute the median quantile.

The process for testing military systems which are largely software intensive involves techniques and procedures often different from those for hardware-based systems. Much of the testing can be performed in laboratories at many of the acquisition stages, up to operational testing. Testing software systems is not different from testing hardware-based systems in that testing earlier and more intensively benefits the acquisition program in the long run. Automated testing of software systems enables more frequent and more extensive testing, allowing for earlier discovery of errors and faults in the code. Automated testing is beneficial for unit, integrated, functional and performance testing, but there are costs associated with automation tool license fees, specialized manpower, and the time to prepare and maintain the automation scripts. This presentation discusses some of the features unique to automated software testing and offers a framework organizations can implement to make the business case for, to organize for, and to execute and benefit from automating the right aspects of their testing needs. Automation has many benefits in saving time and money, but is most valuable in freeing test resources to perform higher value tasks.

Rigorous, efficient and effective test science techniques are individually taking hold in many software centric DoD acquisition programs, both in developmental and operational test regimes. These techniques include agile software development, cybersecurity test and evaluation (T&E), design and analysis of experiments and automated software testing. Many software centric programs must also be tested together with other systems to demonstrate they can be successfully integrated into a more complex systems of systems. This presentation focuses on the two test science disciplines of designed experiments (DOE) and automated software testing (AST) and describes how they can be used effectively and leverage one another in planning for and executing a system of systems test strategy. We use the Navy’s Distributed Common Ground System as an example.