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Operations Research, Systems Engineering and Industrial Engineering Commons™
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- Computational complexity (3)
- Heterogeneous networks (3)
- Approximation bounds (2)
- Data processing (2)
- Nash equilibrium (2)
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- Residual stress (2)
- Simulation (2)
- Wireless networks (2)
- X-ray diffraction (2)
- 7075 aluminum alloys (1)
- ADMM algorithm (1)
- Aberdeen (1)
- Access point selection (1)
- Adaptable automation (1)
- Adaptive automation (1)
- Adaptive systems (1)
- Agriculture (1)
- Aircraft data (1)
- Alloys (1)
- Alternating direction method of multipliers (ADMM) (1)
- Alumina (1)
- Aluminum alloys (1)
- Aluminum metallurgy (1)
- Automated systems (1)
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- Bandwidth choice (1)
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- Base station association (1)
- Base station clustering (1)
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Articles 1 - 30 of 42
Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering
A Bayesian Beta Kernel Model For Binary Classification And Online Learning Problems, Cameron A. Mackenzie, Theodore B. Trafalis, Kash Barker
A Bayesian Beta Kernel Model For Binary Classification And Online Learning Problems, Cameron A. Mackenzie, Theodore B. Trafalis, Kash Barker
Cameron A. MacKenzie
Recent advances in data mining have integrated kernel functions with Bayesian probabilistic analysis of Gaussian distributions. These machine-learning approaches can incorporate prior information with new data to calculate probabilistic rather than deterministic values for unknown parameters. This article extensively analyzes a specific Bayesian kernel model that uses a kernel function to calculate a posterior beta distribution that is conjugate to the prior beta distribution. Numerical testing of the beta kernel model on several benchmark datasets reveals that this model's accuracy is comparable with those of the support vector machine (SVM), relevance vector machine, naive Bayes, and logistic regression, and the …
A New Fuzzy Logic Approach To Capacitated Dynamic Dial-A-Ride Problem, Maher Maalouf, Cameron A. Mackenzie, Sridhar Radakrishnan, Mary Court
A New Fuzzy Logic Approach To Capacitated Dynamic Dial-A-Ride Problem, Maher Maalouf, Cameron A. Mackenzie, Sridhar Radakrishnan, Mary Court
Cameron A. MacKenzie
Almost all Dial-a-Ride problems (DARP) described in the literature pertain to the design of optimal routes and schedules for n customers who specify pick-up and drop-off times. In this article we assume that the customer is mainly concerned with the drop-off time because it is the most important to the customer. Based on the drop-off time specified by the customer and the customer's location, a pick-up time is calculated and given to the customer by the dispatching office. We base our formulation on a dynamic fuzzy logic approach in which a new request is assigned to a vehicle. The fuzzy …
Outage Constrained Robust Secure Transmission For Miso Wiretap Channels, Shuai Ma, Mingyi Hong, Engin Song, Xiangfeng Wang, Dechun Sun
Outage Constrained Robust Secure Transmission For Miso Wiretap Channels, Shuai Ma, Mingyi Hong, Engin Song, Xiangfeng Wang, Dechun Sun
Mingyi Hong
In this paper, we consider the robust secure beam-former design for multiple-input-single-output wiretap channels. Assuming that the eavesdroppers' channels are only partially available at the transmitter, we seek to maximize the secrecy rate under the transmit power and the secrecy rate outage probability constraint. The outage probability constraint requires that the secrecy rate exceed certain thresholds with high probability. Therefore, including such constraint in the design naturally ensures the desired robustness. Unfortunately, the presence of the probabilistic constraints makes the problem nonconvex and, hence, difficult to solve. In this paper, we investigate the outage probability constrained secrecy rate maximization problem …
Base Station Activation And Linear Transceiver Design For Optimal Resource Management In Heterogeneous Networks, Wei-Cheng Liao, Mingyi Hong, Ya-Feng Liu, Zhi-Quan Luo
Base Station Activation And Linear Transceiver Design For Optimal Resource Management In Heterogeneous Networks, Wei-Cheng Liao, Mingyi Hong, Ya-Feng Liu, Zhi-Quan Luo
Mingyi Hong
In a densely deployed heterogeneous network (HetNet), the number of pico/micro base stations (BS) can be comparable with the number of the users. To reduce the operational overhead of the HetNet, proper identification of the set of serving BSs becomes an important design issue. In this work, we show that by jointly optimizing the transceivers and determining the active set of BSs, high system resource utilization can be achieved with only a small number of BSs. In particular, we provide formulations and efficient algorithms for such joint optimization problem, under the following two common design criteria: i) minimization of the …
Min Flow Rate Maximization For Software Defined Radio Access Networks, Wei-Cheng Liao, Mingyi Hong, Hamid Farmanbar, Xu Li, Zhi-Quan Luo, Hang Zhang
Min Flow Rate Maximization For Software Defined Radio Access Networks, Wei-Cheng Liao, Mingyi Hong, Hamid Farmanbar, Xu Li, Zhi-Quan Luo, Hang Zhang
Mingyi Hong
We consider a cloud-based heterogeneous network of base stations (BSs) connected via a backhaul network of routers and wired/wireless links with limited capacity. The optimal provision of such networks requires proper resource allocation across the radio access links in conjunction with appropriate traffic engineering within the backhaul network. In this paper, we propose an efficient algorithm for joint resource allocation across the wireless links and flow control over the entire network. The proposed algorithm, which maximizes the min-rate among all the transmitted commodities, is based on a decomposition approach that leverages both the alternating direction method of multipliers (ADMM) and …
Modeling A Severe Supply Chain Disruption And Post-Disaster Decision Making With Application To The Japanese Earthquake And Tsunami, Cameron A. Mackenzie, Kash Barker, Joost R. Santos
Modeling A Severe Supply Chain Disruption And Post-Disaster Decision Making With Application To The Japanese Earthquake And Tsunami, Cameron A. Mackenzie, Kash Barker, Joost R. Santos
Cameron A. MacKenzie
Modern supply chains are increasingly vulnerable to disruptions, and a disruption in one part of the world can cause supply difficulties for companies around the globe. This article develops a model of severe supply chain disruptions in which several suppliers suffer from disabled production facilities and firms that purchase goods from those suppliers may consequently suffer a supply shortage. Suppliers and firms can choose disruption management strategies to maintain operations. A supplier with a disabled facility may choose to move production to an alternate facility, and a firm encountering a supply shortage may be able to use inventory or buy …
Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo
Joint User Grouping And Linear Virtual Beamforming: Complexity, Algorithms And Approximation Bounds, Mingyi Hong, Zi Xu, Meisam Razaviyayn, Zhi-Quan Luo
Mingyi Hong
In a wireless system with a large number of distributed nodes, the quality of communication can be greatly improved by pooling the nodes to perform joint transmission/reception. In this paper, we consider the problem of optimally selecting a subset of nodes from potentially a large number of candidates to form a virtual multi-antenna system, while at the same time designing their joint linear transmission strategies. We focus on two specific application scenarios: 1) multiple single antenna transmitters cooperatively transmit to a receiver; 2) a single transmitter transmits to a receiver with the help of a number of cooperative relays. We …
Joint Access Point Selection And Power Allocation For Uplink Wireless Networks, Mingyi Hong, Alfredo Garcia, Jorge Barrera, Stephen G. Wilson
Joint Access Point Selection And Power Allocation For Uplink Wireless Networks, Mingyi Hong, Alfredo Garcia, Jorge Barrera, Stephen G. Wilson
Mingyi Hong
We consider the distributed uplink resource allocation problem in a multi-carrier wireless network with multiple access points (APs). Each mobile user can optimize its own transmission rate by selecting a suitable AP and by controlling its transmit power. Our objective is to devise suitable algorithms by which mobile users can jointly perform these tasks in a distributed manner. Our approach relies on a game theoretic formulation of the joint power control and AP selection problem. In the proposed game, each user is a player with an associated strategy containing a discrete variable (the AP selection decision) and a continuous vector …
Distributed Linear Precoder Optimization And Base Station Selection For An Uplink Heterogeneous Network, Mingyi Hong, Zhi-Quan Luo
Distributed Linear Precoder Optimization And Base Station Selection For An Uplink Heterogeneous Network, Mingyi Hong, Zhi-Quan Luo
Mingyi Hong
In a heterogeneous wireless cellular network, each user may be covered by multiple access points such as macro/pico/relay/femto base stations (BS). An effective approach to maximize the sum utility (e.g., system throughput) in such a network is to jointly optimize users' linear procoders as well as their BS associations. In this paper, we first show that this joint optimization problem is NP-hard and thus is difficult to solve to global optimality. To find a locally optimal solution, we formulate the problem as a noncooperative game in which the users and the BSs both act as players. We introduce a set …
Extremes Of Nonlinear Vibration: Comparing Models Based On Moments, L-Moments, And Maximum Entropy, Steven R. Winterstein, Cameron A. Mackenzie
Extremes Of Nonlinear Vibration: Comparing Models Based On Moments, L-Moments, And Maximum Entropy, Steven R. Winterstein, Cameron A. Mackenzie
Cameron A. MacKenzie
Wind and wave loads on offshore structures show nonlinear effects, which require nonGaussian statistical models. Here we critically review the behavior of various nonGaussian models. We first survey moment-based models; in particular, the four-moment “Hermite” model, a cubic transformation often used in wind and wave applications. We then derive an “L-Hermite” model, an alternative cubic transformation calibrated by the response “L-moments” rather than its ordinary statistical moments. These L-moments have recently found increasing use, in part because they show less sensitivity to distribution tails than ordinary moments. We find here, however, that these L-moments may not convey sufficient information to …
Joint Base Station Clustering And Beamformer Design For Partial Coordinated Transmission In Heterogeneous Networks, Mingyi Hong, Ruoyu Sun, Hadi Baligh, Zhi-Quan Luo
Joint Base Station Clustering And Beamformer Design For Partial Coordinated Transmission In Heterogeneous Networks, Mingyi Hong, Ruoyu Sun, Hadi Baligh, Zhi-Quan Luo
Mingyi Hong
We consider the interference management problem in a multicell MIMO heterogeneous network. Within each cell there is a large number of distributed micro/pico base stations (BSs) that can be potentially coordinated for joint transmission. To reduce coordination overhead, we consider user-centric BS clustering so that each user is served by only a small number of (potentially overlapping) BSs. Thus, given the channel state information, our objective is to jointly design the BS clustering and the linear beamformers for all BSs in the network. In this paper, we formulate this problem from a {sparse optimization} perspective, and propose an efficient algorithm …
Empirical Data And Regression Analysis For Estimation Of Infrastructure Resilience With Application To Electric Power Outages, Cameron A. Mackenzie, Kash Barker
Empirical Data And Regression Analysis For Estimation Of Infrastructure Resilience With Application To Electric Power Outages, Cameron A. Mackenzie, Kash Barker
Cameron A. MacKenzie
Recent natural disasters have highlighted the need for increased planning for disruptive events. Forecasting damage and time that a system will be inoperable is important for disruption planning. The resilience of critical infrastructure systems, or their ability to recover quickly from a disruption, can mitigate adverse consequences of the disruption. This paper quantifies the resilience of a critical infrastructure sector through the dynamic inoperability input-output model (DIIM). The DIIM, which describes how inoperability propagates through a set of interdependent industry and infrastructure sectors following a disruptive event, includes a resilience parameter that has not yet been adequately assessed. This paper …
A Unified Convergence Analysis Of Block Successive Minimization Methods For Nonsmooth Optimization, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo
A Unified Convergence Analysis Of Block Successive Minimization Methods For Nonsmooth Optimization, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo
Mingyi Hong
The block coordinate descent (BCD) method is widely used for minimizing a continuous function f of several block variables. At each iteration of this method, a single block of variables is optimized, while the remaining variables are held fixed. To ensure the convergence of the BCD method, the subproblem of each block variable needs to be solved to its unique global optimal. Unfortunately, this requirement is often too restrictive for many practical scenarios. In this paper, we study an alternative inexact BCD approach which updates the variable blocks by successively minimizing a sequence of approximations of f which are either …
Linear Transceiver Design For A Mimo Interfering Broadcast Channel Achieving Max–Min Fairness, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo
Linear Transceiver Design For A Mimo Interfering Broadcast Channel Achieving Max–Min Fairness, Meisam Razaviyayn, Mingyi Hong, Zhi-Quan Luo
Mingyi Hong
This problem can be formulated as maximizing the minimum rate among all the users in an interfering broadcast channel (IBC). In this paper we show that when the number of antennas is at least two at each of the transmitters and the receivers, the min rate maximization problem is NP-hard in the number of users. Moreover, we develop a low-complexity algorithm for this problem by iteratively solving a sequence of convex subproblems. We theoretically establish the global convergence of the proposed algorithm to the set of stationary points, which may be suboptimal due to the non-convexity of the original minimum …
Mechanism Design For Base Station Association And Resource Allocation In Downlink Ofdma Network, Mingyi Hong, Alfredo Garcia
Mechanism Design For Base Station Association And Resource Allocation In Downlink Ofdma Network, Mingyi Hong, Alfredo Garcia
Mingyi Hong
We consider a resource management problem in a multi-cell downlink OFDMA network whereby the goal is to find the optimal combination of (i) assignment of users to base stations and (ii) resource allocation strategies at each base station. Efficient resource management protocols must rely on users truthfully reporting privately held information such as downlink channel states. However, individual users can manipulate the resulting resource allocation (by misreporting their private information) if by doing so they can improve their payoff. Therefore, it is of interest to design efficient resource management protocols that are strategy-proof, i.e. it is in the users' best …
Analysis Of The Risks And Benefits Of Flight Deck Adaptive Systems, Michael C. Dorneich, William Rogers, Stephen D. Whitlow, Robert Demers
Analysis Of The Risks And Benefits Of Flight Deck Adaptive Systems, Michael C. Dorneich, William Rogers, Stephen D. Whitlow, Robert Demers
Michael C. Dorneich
The objectives of this work were to identify human performance risks and benefits of adaptive systems through a systematic analysis and heuristic evaluation of adaptive system component types and characteristics. As flight deck automated systems have more access to aircraft data, sensor data, stored databases, communicated information, and real time flight crew inputs, as well as more ability to process that information in sophisticated ways to identify situational priorities and context, it is becoming more realistic for those automated systems to adapt their behavior based on context. Automated systems that can make such changes on their own are called adaptive …
Towards A Characterization Of Adaptive Systems: A Framework For Researchers And System Designers, Karen M. Feigh, Michael C. Dorneich, Caroline C. Hayes
Towards A Characterization Of Adaptive Systems: A Framework For Researchers And System Designers, Karen M. Feigh, Michael C. Dorneich, Caroline C. Hayes
Michael C. Dorneich
Objective: This paper presents a systematic framework characterizing adaptive systems. Background: Adaptive systems are those which can appropriately modify their behavior to fit the current context. This concept is appealing because it offers the possibility of creating computer assistants that behave like good human assistants who can provide what is needed without being asked. However, the majority of adaptive systems have been experimental rather than practical because of the technical challenges in accurately perceiving and interpreting users’ current cognitive state; integrating cognitive state, environment and task information; and using it to predict users’ current needs. We anticipate that recent developments …
Measuring Changes In International Production From A Disruption: Case Study Of The Japanese Earthquake And Tsunami, Cameron A. Mackenzie, Joost R. Santos, Kash Barker
Measuring Changes In International Production From A Disruption: Case Study Of The Japanese Earthquake And Tsunami, Cameron A. Mackenzie, Joost R. Santos, Kash Barker
Cameron A. MacKenzie
The earthquake and tsunami that struck Japan on March 11, 2011 caused a tremendous loss of life and property. The disaster also disrupted global supply chains, which was blamed for anemic growth in the global economy. A multiregional input-output model can quantify the international impacts on production due to changes in demand from companies reducing their orders because of a disruption. Using the input-output model to conceptualize a supply chain, we present a unique method for calculating indirect production losses caused by disabled production facilities. Methods for calculating the possible transfer of demand to industries in other countries are also …
Evaluating The Consequences Of An Inland Waterway Port Closure With A Dynamic Multiregional Interdependence Model, Cameron A. Mackenzie, Kash Barker, F. Hank Grant
Evaluating The Consequences Of An Inland Waterway Port Closure With A Dynamic Multiregional Interdependence Model, Cameron A. Mackenzie, Kash Barker, F. Hank Grant
Cameron A. MacKenzie
As intermodal hubs connecting barge, train, and truck transportation modes, inland ports play an important role in U.S. and global commerce. Like coastal ports, inland ports face the risk of malevolent attacks, man-made accidents, and natural disasters. However, most port impact studies focus on the consequences of one of these disruptive events suddenly closing a coastal port. This paper examines the economic impact of suddenly closing an inland port by combining a simulation and a multiregional input-output model. The simulation models how companies may react if an inland waterway port suddenly closes, and the multiregional dynamic inoperability input-output model quantifies …
Averaged Iterative Water-Filling Algorithm: Robustness And Convergence, Mingyi Hong, Alfredo Garcia
Averaged Iterative Water-Filling Algorithm: Robustness And Convergence, Mingyi Hong, Alfredo Garcia
Mingyi Hong
The convergence properties of the iterative water-filling (IWF) based algorithms have been derived in the ideal situation where the transmitters in the network are able to obtain the exact value of the interference plus noise (IPN) experienced at the corresponding receivers in each iteration of the algorithm. However, these algorithms are not robust because they diverge when there is time-varying estimation error of the IPN, a situation that arises in real communication system. In this correspondence, we propose an algorithm that possesses convergence guarantees in the presence of various forms of such time-varying error. Moreover, we also show by simulation …
Kernel Regression In The Presence Of Correlated Errors, Kris De Brabanter, Jos De Brabanter, Johan A.K. Suykens, Bart De Moor
Kernel Regression In The Presence Of Correlated Errors, Kris De Brabanter, Jos De Brabanter, Johan A.K. Suykens, Bart De Moor
Kris De Brabanter
It is a well-known problem that obtaining a correct bandwidth and/or smoothing parameter in nonparametric regression is difficult in the presence of correlated errors. There exist a wide variety of methods coping with this problem, but they all critically depend on a tuning procedure which requires accurate information about the correlation structure. We propose a bandwidth selection procedure based on bimodal kernels which successfully removes the correlation without requiring any prior knowledge about its structure and its parameters. Further, we show that the form of the kernel is very important when errors are correlated which is in contrast to the …
Understanding Student Pathways In Context-Rich Problems, Pavlo Antonenko, John Jackman, Piyamart Kumsaikaew, Rahul Marathe, Dale Niederhauser, Craig Ogilvie, Sarah Ryan
Understanding Student Pathways In Context-Rich Problems, Pavlo Antonenko, John Jackman, Piyamart Kumsaikaew, Rahul Marathe, Dale Niederhauser, Craig Ogilvie, Sarah Ryan
Sarah M. Ryan
In this paper we investigate the ways that students' problem-solving behaviors evolve when solving multi-faceted, context-rich problems within a structured, computer-based learning environment. During the semester, groups of two or three students worked on several problems that required drawing on more than one concept and, hence, could not be readily solved with simple "plug-and-chug" strategies. The problems were presented to students in a data-rich, online problem-solving environment that tracked which information items were selected by students as they attempted to solve the problem. The students also completed a variety of tasks, like entering an initial qualitative analysis into an online …
Book Review On The Failure Of Risk Management: Why It’S Broken And How To Fix It, By Douglas W. Hubbard (2009)., Cameron A. Mackenzie
Book Review On The Failure Of Risk Management: Why It’S Broken And How To Fix It, By Douglas W. Hubbard (2009)., Cameron A. Mackenzie
Cameron A. MacKenzie
The title The Failure of Risk Management seemsto imply that risk management is useless. However,the subtitle Why It’s Broken and How to Fix It provides a better description of Douglas Hubbard’s contribution to the field of risk analysis. Hubbard criticizes several risk management methods currently used by a wide variety of organizations but also presents a convincing argument for why probabilistic risk analysis using Monte Carlo simulation is the best approach.
Improving Shared Understanding In Multilevel Planning, Michael C. Dorneich, David Mott, Ali Bahrami, Jitu Patel
Improving Shared Understanding In Multilevel Planning, Michael C. Dorneich, David Mott, Ali Bahrami, Jitu Patel
Michael C. Dorneich
Planning is a specific example of a problem solving activity that is undertaken across multiple (human) collaborative agents. In order to collaborate, these humans need to form a shared understanding of various aspects of the plan, mutual goals, the contexts of the other agents, and the rationale for others decisions and assumptions. Failure to reach this shared understanding can have serious implications to the success of the resulting plan. Currently plans are developed and shared with peer and subordinate units in a static format such as text, diagrams and spreadsheets which do not normally contain any of the reasoning, logic …
An Investigation Of The Residual Stress Characterization And Relaxation In Peened Friction Stir Welded Aluminum–Lithium Alloy Joints, Omar Hatamleh, Iris V. Rivero, Shayla E. Swain
An Investigation Of The Residual Stress Characterization And Relaxation In Peened Friction Stir Welded Aluminum–Lithium Alloy Joints, Omar Hatamleh, Iris V. Rivero, Shayla E. Swain
Iris V. Rivero
In this investigation the residual stresses generated from friction stir welded (FSW) 2195 aluminum–lithium alloy joints were characterized. The results derived from this research revealed significant levels of tensile residual stresses at the surface and throughout the thickness of the FSW samples. Furthermore, residual stress relaxation at the surface and throughout the thickness of the samples was assessed for laser peened friction stir welded aluminum–lithium joints. To do so the samples were cycled several times at a constant amplitude load. The results indicated that most of the relaxation for the surface residual stresses took place during the first cycle of …
Component Obsolescence Risk Assessment, Craig Josais, Janis P. Terpenny, Kenneth J. Mclean
Component Obsolescence Risk Assessment, Craig Josais, Janis P. Terpenny, Kenneth J. Mclean
Janis P. Terpenny
Custom low volume products and systems, such as those utilized by military and avionics applications; often make use of commercial high-tech components. In the past decade, technology has advanced very rapidly causing such components to have a shortened life span. Newer and better technologies are being introduced frequently, rendering components obsolete. Yet, custom low volume products and systems such as ships, submarines and aircraft can be in use for decades. Being proactive about obsolescence is critical to maintaining fully capable products and systems and satisfied customers. This paper presents an obsolescence risk measurement tool that is being developed to better …
Residual Stresses In Friction-Stir-Welded 2195 And 7075 Aluminum Alloys, Omar Hatamleh, Iris V. Rivero, Arif Maredia
Residual Stresses In Friction-Stir-Welded 2195 And 7075 Aluminum Alloys, Omar Hatamleh, Iris V. Rivero, Arif Maredia
Iris V. Rivero
Surface residual stresses (RSs) were characterized along friction-stir-welded 2195 and 7075 aluminum alloy (AA) plates. The surface measurements were obtained through X-ray diffraction (XRD) at five different locations along the weld. Each location consisted of several regions across the welded plate including the weld nugget, thermomechanically affected zone (TMAZ), heat-affected zone (HAZ), and base material. Measurements revealed that RSs were not uniform along the welded plate, with the highest RSs obtained on the middle of the plate. The RSs across the weld were also asymmetric relative to the weld centerline, with RSs as high as 231 MPa in the TMAZ …
The Effect Of A Knee Support On The Biomechanical Response Of The Low Back, Yu Shu, Zongliang Jiang, Xu Xu, Gary A. Mirka
The Effect Of A Knee Support On The Biomechanical Response Of The Low Back, Yu Shu, Zongliang Jiang, Xu Xu, Gary A. Mirka
Gary A. Mirka
Stooping and squatting postures are seen in a number of industries (e.g., agriculture, construction) where workers must work near ground level for extended periods of time. The focus of the current research was to evaluate a knee support device designed to reduce the biomechanical loading of these postures. Ten participants performed a series of sudden loading tasks while in a semisquat posture under two conditions of knee support (no support and fully supported) and two conditions of torso flexion (45 and 60°). A weight was released into the hands of the participants who then came to steady state while maintaining …
Evaluation Of Surface Residual Stresses In Friction Stir Welds Due To Laser And Shot Peening, Omar Hatamleh, Iris V. Rivero, Jeds Lyons
Evaluation Of Surface Residual Stresses In Friction Stir Welds Due To Laser And Shot Peening, Omar Hatamleh, Iris V. Rivero, Jeds Lyons
Iris V. Rivero
The effects of laser, and shot peening on the residual stresses in friction stir welds (FSW) has been investigated. The surface residual stresses were measured at five different locations across the weld in order to produce an adequate residual stress profile. The residual stresses before and after sectioning the coupon from the welded plate were also measured, and the effect of coupon size on the residual stress relaxation was determined and characterized. Measurements indicate that residual stresses were not uniform along the welded plate, and large variation in stress magnitude could be exhibited at various locations along the FSW plate. …
An Evaluation Of Real-Time Cognitive State Classification In A Harsh Operational Environment, Michael C. Dorneich, Santosh Mathan, Patricia May Ververs, Stephen D. Whitlow
An Evaluation Of Real-Time Cognitive State Classification In A Harsh Operational Environment, Michael C. Dorneich, Santosh Mathan, Patricia May Ververs, Stephen D. Whitlow
Michael C. Dorneich
This paper describes an evaluation conducted with a full platoon of 32 Soldiers at Aberdeen Proving Grounds' MOUT site in Aberdeen, MD. The objective was to assess the cognitive workload classification techniques driven by neuro-physiological (EEG) and physiological (ECG) sensors. In a first ever evaluation of real-time cognitive monitoring in the harsh operational environment, the assessment culminated in a three phase, 24-hour mission consisting of a coordinated Route Reconnaissance, a Cordon and Search of a village, and a Hasty Defense operation. Task load levels were manipulated by introducing unexpected and unplanned events requiring re-planning and extensive coordination by the leadership …