USMA Digital Commons (United States Military Academy, West Point)
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PDCunplugged: A free repository of unplugged parallel & distributed computing activities
No full textIntegrating parallel and distributed computing (PDC) topics in core computing courses is a topic of increasing interest for educators. However, there is a question of how best to introduce PDC to undergraduates. Several educators have proposed the use of “unplugged activities”, such as role-playing dramatizations and analogies, to introduce PDC concepts. Yet, unplugged activities for PDC are widely-scattered and often difficult to find, making it challenging for educators to create and incorporate unplugged interventions in their classrooms. The PDCunplugged project seeks to rectify these issues by providing a free repository where educators can find and share unplugged activities related to PDC. The existing curation contains nearly forty unique unplugged activities collected from thirty years of the PDC literature and from all over the Internet, and maps each activity to relevant CS2013 PDC knowledge units and TCPP PDC topic areas. Learn more about the project at pdcunplugged.org
Undergraduate Internal Flow Pipe Friction Laboratory
Get PDFHydrodynamics laboratory experiences have supported the United States Military Academy’s civil and mechanical engineering programs for nearly 50 years. A recent effort revitalized and significantly improved the pipe friction hydrodynamics laboratory, a system originally built by the U.S. Army Corps of Engineers Waterways Experiment Station in the 1950s. The experimental apparatus includes a 3 hp electric pump capable of delivering a steady flow of liquid up to 5:1 lbm=s fed from a 100 gallon (US) reservoir. The test section is a horizontal copper pipe of 0:75 in diameter which issues fluid into a transparent, plastic visualization chamber. Mineral oil is the working fluid, chosen for its favorable physical properties that enable a broad range of flow regimes for data analysis and flow visualization. The test section is instrumented with digital pressure gauges and an ultrasonic flow meter, installed as part of the revitalization project. A collection tank on a mass scale provides a manual method for estimating flow rate during experimental trials. The improved laboratory significantly expands the range of data that may be collected, with students now able to accurately measure pressure, temperature, flow rate, and pipe geometric data. Students compute Reynolds number to characterize flow regime, estimate pressure gradient, and predict the friction factor given an estimate for the pipe’s roughness coefficient for several flow rates. A pre-laboratory exercise requires students to derive a functional form of the steady-flow mechanical pipe flow equation and employ dimensional analysis to identify the non-dimensional parameters required to achieve dynamic similitude. The upgraded laboratory offers a relevant, comprehensive application to deepen students’ conceptual understanding of internal fluid flow, hydrodynamics, and modeling and similarity principles
Energy generating potential of anaerobically enhanced primary treatment of domestic wastewater using multiple-compartment bioreactors
No full textWastewater reclamation facilities have the potential to be net energy producers if anaerobic bioreactors coupled with energy-generating technologies, such as combined heat and power (CHP), are employed. To characterize the energy-generating potential of multiple-compartment anaerobic bioreactors used for enhanced primary treatment of domestic wastewater, organic removal and observed methane (CH4) generation from two pilot-scale anaerobic baffled bioreactors operating for more than 2400 days over a range of wastewater temperatures (11 to 24 °C) were characterized. Aggregated data from both bioreactor systems were subjected to uncertainty analysis and modeling to increase confidence in results and to determine the energy-generating potential from five different CHP technologies. Results suggest that multiple-compartment anaerobic reactors converted 76% of the chemical oxygen demand (COD) removed to methane-rich biogas (effective energy content of 2.0 kW h kg−1 COD removed). Observed CH4 production was most accurately modeled using total COD measurements, not biodegradable COD estimates. The use of the aerobic biochemical oxygen demand (BOD) assay underestimated the amount of anaerobically biodegradable COD. Modeled scenarios suggest that energy generated from several CHP technologies with heat recovery (i.e., effective electrical energy) can provide power equivalent to the amount used by many conventional activated sludge systems. A modeled future scenario where dissolved methane (dCH4) is recovered for energy generation also suggests that dCH4 capture provides additional energy generation and is needed to reduce greenhouse gas emissions. Based on COD, mass balances indicate that using multiple-compartment anaerobic reactors for anaerobically enhanced primary treatment increases the portion of COD in the influent wastewater going to electrical energy from ∼8.5% to 21%. Results from this study suggest that replacing conventional primary treatment with anaerobic bioreactors can enhance energy-generating potential at water resource recovery facilities
Technical communications in an environmental engineering curriculum: a framework for analysis and continual improvement
No full textThe ability to effectively communicate technical information is an important skill for engineers, especially young engineers entering the workforce upon completion of their education. Undergraduate environmental engineering programs normally address technical communications, but some do not provide intentionally placed discipline-specific technical communication experiences designed to progressively increase communication skills through the curriculum. Conducting a crosswalk of graded events with a technical communication component across a curriculum can help an institution understand the placement of technical communication graded events and identify opportunities for improvement. This study presents a survey-based approach for gathering information about all technical communication graded events within an environmental engineering curriculum and a method for analysis using a longitudinal crosswalk of all applicable courses from freshman to senior year. Results from this study indicate that the number of graded technical communication events in our program increases longitudinally from freshman to senior year. Further, the number of individually completed events and written events were highest in the sophomore year, with team events and oral communication events increasing in the junior and senior years. Additionally, the weighting of graded events shifted longitudinally through major courses. Graded events worth \u3c 5% of the course grade were most prevalent in the sophomore year, and events worth ≥ 5% occurred most frequently in the senior year. Implications for our university’s environmental engineering program are discussed, to include opportunities for scaffolding events across courses. The methods presented in this study can be used by other environmental engineering programs to identify gaps in technical communication education and methods for improvement within their curriculum
Analytical Modeling of Stochastic Systems
No full textThis chapter is to promote and encourage the modeling of stochastic systems with analytical models rather than discrete event simulation (DES). DES has many advantages, including flexibility and ease of explanation, but it also requires multiple runs and statistical treatment of their results. DESs also tend to grow in detail and complexity, making them harder and harder to interpret. Analytical models, such as Markov chains and queuing models, give quick answers, but they require a mathematical structure, and they are more abstract and harder to explain. Despite this balance of advantages and disadvantages, simulation is more widely used than analytical models in the practice of military operations research. A brief review of DES and analytical modeling is given, including a sample of some fundamental results and the particular advantages and disadvantages of each. This is followed by a direct comparison, including results from modeling a system that is easily modeled each way. Two examples are presented of analytical modeling of military systems that one might expect to be modeled in a DES. There is a discussion of the imprecision in results from assumptions required to fit a real situation into an analytical framework, with a numerical example
Kaggle Competitions in the Classroom: Retrospectives and Recommendations
No full textInteresting tool allows educators to add motivation and inject friendly competition into their data sciences courses
iRebot: An Interactive Rehabilitation Robot with Gesture Control
No full textPhysical therapy efficacy relies on patient compliance and motivation. However, the monotony, intensity, and expense of most therapy routines do not promote engagement. Technology-based rehabilitation has the potential to provide engaging and cost-effective treatment, leading to better compliance and mobility outcomes. We present an interactive rehabilitation robot (iRebot) as an affordable, gesture-controlled vehicle that can provide a form of entertainment while conducting physical therapy. Healthy participants (n=11) executed a test maze with the iRebot for six repeated trials, three with each hand. Survey scores and quantitative metrics were evaluated to assess system usability and baseline motor performance, respectively. Wrist mobility across participants was evaluated, with an active range of motion of 39.7± 13° and 72.8± 18° for pitch and roll, respectively. In the course of conducting a single trial (time duration=87.2±67 sec), the participants performed on average 30 full wris t motion repetitions (e.g., flexion/extension). Participants rated the system\u27s usability as excellent (survey score: 85 ± 13), and all participants indicated they would prefer iRebot over standard therapy. The iRebot demonstrated potential as an evidence-based rehabilitation tool based on excellent user ratings and the ability to monitor at- home compliance and motor performance
Constitutive Modeling and Initial Validation of Cellular Concrete Subjected to Large Strains and High Strain Rates
No full textThe development of lead-free small caliber weapon systems has inadvertently resulted in rounds with more material penetration capabilities. The increased penetration may mean that existing live-fire facilities will no longer be adequate for the training and certification of military and law enforcement personnel. Constraints on training in many live-fire shoot house facilities are already in place, with some allowing only single round impact during training. With no existing constitutive model for the cellular concrete commonly used in these facilities, it is not currently possible to analyze existing facilities or design new facilities against the most recent generation of ammunition currently being fielded. This project utilizes unconfined compression, uniaxial tension, triaxial confinement, and uniaxial strain from the US Army Corps of Engineers Engineer Research and Development Center and Sandia National Laboratory to characterize cellular concrete using a Holmquist-Johnson-Cook Concrete model for use in numerical simulations. This model is then initially validated using data from existing single projectile impact experiments against a similar material, showing results with reasonable accuracy. Additional experiments to fully validate the proposed model are discussed.
This model provides the facility owner a potential tool to validate the safety of their facility against new projectiles and provides the designer of new facilities a tool for optimizing future configurations using these materials
Early predictors of successful military careers among West Point cadets
No full textThe importance of leadership to organizational performance puts a premium on identifying future leaders. Early prediction of high-potential talent enables organizations to marshal scarce developmental resources and opportunities to those who are best positioned to show distinction in elevated roles. Much of the existing literature indicates that general mental ability remains the strongest predictor of future professional performance. Using data from 13 classes of West Point graduates who stayed in the Army to be considered for at least early promotion to the rank of major (N = 5,505), regression analyses indicate that cadet military grade point average surpasses both cognitive ability and academic performance by a considerable margin in the ability to predict future professional outcomes such as selection for early promotion or battalion command. Moreover, these differences in predicting managerial career outcomes endure over 16 years. Both practical and theoretical implications are discussed
Jack Voltaic®: Bolstering Critical Infrastructure Resilience
No full textAccording to the Department of Homeland Security (DHS), municipal critical infrastructure has become an ideal target for a range of cyber threat actors including near-peer competitors seeking geopolitical gains and decentralized cyber criminals attempting to hold cities captive for monetary gain. With municipalities predominantly partnering with the private sector for operation of national critical infrastructure as defined in Presidential Policy Directive (PPD) 21, cities, states, and industry entities find themselves on the front lines—possibly the first line of defense—against a perpetual barrage of attacks in cyberspace. Accordingly, a dynamic shift from traditional conflict in the physical world to a homeland defense posture in cyberspace reveals several potential gaps with regard to handling emergency situations, coordinating response efforts, and restoring basic services for citizens. This article seeks to highlight this dynamic environment, and the inherent gaps that exist in bolstering critical infrastructure resilience. Accordingly, the Jack Voltaic® (JV) research framework discussed in this article explores the interconnections among municipal, state, and federal response efforts during a cyber emergency scenario, with added emphasis on critical findings and themes from its Jack Voltaic® 2.5 workshop series. This effort brought together key regional stakeholders from across various levels of governance, the private sector, and academia to discuss the findings of previous JV exercises, lessons learned, and how similar efforts can strengthen critical infrastructure, community resilience, and a whole-of-nation approach to handling cyber threats. This article will highlight common findings and themes from multiple exercises and workshops that further reinforce current JV research and the Jack Voltaic® 3.0 Legal and Policy Tabletop Exercise (TTX). Finally, this article concludes with a detailed discussion about JV 3.0, which is scheduled to execute in September 2020