Sample records for resilient aircraft control
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Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Sandifer, Carl E.; Jones, Sharon Monica
2010-01-01
The causal factors of accidents from the National Transportation Safety Board (NTSB) database and incidents from the Federal Aviation Administration (FAA) database associated with loss of control (LOC) were examined for four types of operations (i.e., Federal Aviation Regulation Part 121, Part 135 Scheduled, Part 135 Nonscheduled, and Part 91) for the years 1988 to 2004. In-flight LOC is a serious aviation problem. Well over half of the LOC accidents included at least one fatality (80 percent in Part 121), and roughly half of all aviation fatalities in the studied time period occurred in conjunction with LOC. An adverse events table was updated to provide focus to the technology validation strategy of the Integrated Resilient Aircraft Control (IRAC) Project. The table contains three types of adverse conditions: failure, damage, and upset. Thirteen different adverse condition subtypes were gleaned from the Aviation Safety Reporting System (ASRS), the FAA Accident and Incident database, and the NTSB database. The severity and frequency of the damage conditions, initial test conditions, and milestones references are also provided.
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Propulsion controlled aircraft computer
Cogan, Bruce R. (Inventor)
2010-01-01
A low-cost, easily retrofit Propulsion Controlled Aircraft (PCA) system for use on a wide range of commercial and military aircraft consists of an propulsion controlled aircraft computer that reads in aircraft data including aircraft state, pilot commands and other related data, calculates aircraft throttle position for a given maneuver commanded by the pilot, and then displays both current and calculated throttle position on a cockpit display to show the pilot where to move throttles to achieve the commanded maneuver, or is automatically sent digitally to command the engines directly.
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Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus
2014-01-01
Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.
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Aircraft Landing and Attitude Control Using Dynamic Matrix Control
Directory of Open Access Journals (Sweden)
George Cristian Calugaru
2017-06-01
Full Text Available This paper proposes a method for an efficient control of the aircraft landing and attitude through Dynamic Matrix Control. The idea of MPC structures used in aircraft control has been well established during the last few years, but some aspects require further investigation. With this in mind, the paper proposes structures for aircraft landing and aircraft attitude control by using single DMC controllers for landing and respectively one DMC controller for each of the attitude axis (pitch attitude hold, bank angle hold and heading hold. The model used for analysis of the aircraft landing structure is based on the last phase of landing. Also, the model used to illustrate the attitude control is that of a pitch attitude hold system of a N250-100 aircraft. Simulations are performed for a variety of control and prediction horizons, taking into account the possibility of adding a weighting factor for the control actions. Apart from separate studies on step reference variations, for some use cases, a generic reference trajectory is provided as a control purpose of the system. Results show a better performance of the proposed method in terms of control surface transition and protection of the actuators involved and a better time response in stabilizing the aircraft attitude. Overall, the aspects shown ensure an improved aircraft attitude control and landing stabilization.
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Resilient Control and Intrusion Detection for SCADA Systems
2014-05-01
Lowe. The myths and facts behind cyber security risks for industrial control systems . VDE Congress, 2004. [45] I. S. C37.1-1994. Ieee standard...Resilient Control and Intrusion Detection for SCADA Systems Bonnie Xia Zhu Electrical Engineering and Computer Sciences University of California at...3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Resilient Control and Intrusion Detection for SCADA Systems 5a. CONTRACT
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Neural networks for aircraft control
Linse, Dennis
1990-01-01
Current research in Artificial Neural Networks indicates that networks offer some potential advantages in adaptation and fault tolerance. This research is directed at determining the possible applicability of neural networks to aircraft control. The first application will be to aircraft trim. Neural network node characteristics, network topology and operation, neural network learning and example histories using neighboring optimal control with a neural net are discussed.
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Control of Next Generation Aircraft and Wind Turbines
Frost, Susan
2010-01-01
The first part of this talk will describe some of the exciting new next generation aircraft that NASA is proposing for the future. These aircraft are being designed to reduce aircraft fuel consumption and environmental impact. Reducing the aircraft weight is one approach that will be used to achieve these goals. A new control framework will be presented that enables lighter, more flexible aircraft to maintain aircraft handling qualities, while preventing the aircraft from exceeding structural load limits. The second part of the talk will give an overview of utility-scale wind turbines and their control. Results of collaboration with Dr. Balas will be presented, including new theory to adaptively control the turbine in the presence of structural modes, with the focus on the application of this theory to a high-fidelity simulation of a wind turbine.
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Measuring Workload Weak Resilience Signals at a Rail Control Post
Siegel, A.W.; Schraagen, J.M.C.
2014-01-01
OCCUPATIONAL APPLICATIONS This article describes an observational study at a rail control post to measure workload weak resilience signals. A weak resilience signal indicates a possible degradation of a system's resilience, which is defined as the ability of a complex socio-technical system to cope
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Integrated controls pay-off. [for flight/propulsion aircraft systems
Putnam, Terrill W.; Christiansen, Richard S.
1989-01-01
It is shown that the integration of the propulsion and flight control systems for high performance aircraft can help reduce pilot workload while simultaneously increasing overall aircraft performance. Results of the Highly Integrated Digital Electronic Control (HiDEC) flight research program are presented to demonstrate the emerging payoffs of controls integration. Ways in which the performance of fighter aircraft can be improved through the use of propulsion for primary aircraft control are discussed. Research being conducted by NASA with the F-18 High Angle-of Attack Research Vehicle is described.
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Robust Control of an Ill-Conditioned Aircraft
DEFF Research Database (Denmark)
Breslin, S.G.; Tøffner-Clausen, S.; Grimble, M.J.
1996-01-01
A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point.......A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point....
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FAULT DIAGNOSIS OF AN AIRCRAFT CONTROL SURFACES WITH AN AUTOMATED CONTROL SYSTEM
Directory of Open Access Journals (Sweden)
Blessing D. Ogunvoul
2017-01-01
Full Text Available This article is devoted to studying of fault diagnosis of an aircraft control surfaces using fault models to identify specific causes. Such failures as jamming, vibration, extreme run out and performance decrease are covered.It is proved that in case of an actuator failure or flight control structural damage, the aircraft performance decreases significantly. Commercial aircraft frequently appear in the areas of military conflicts and terrorist activity, where the risk of shooting attack is high, for example in Syria, Iraq, South Sudan etc. Accordingly, it is necessary to create and assess the fault model to identify the flight control failures.The research results demonstrate that the adequate fault model is the first step towards the managing the challenges of loss of aircraft controllability. This model is also an element of adaptive failure-resistant management model.The research considers the relationship between the parameters of an i th state of a control surface and its angular rate, also parameters classification associated with specific control surfaces in order to avoid conflict/inconsistency in the determination of a faulty control surface and its condition.The results of the method obtained in this article can be used in the design of an aircraft automated control system for timely identification of fault/failure of a specific control surface, that would contribute to an effective role aimed at increasing the survivability of an aircraft and increasing the acceptable level of safety due to loss of control.
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Multidisciplinary Techniques and Novel Aircraft Control Systems
Padula, Sharon L.; Rogers, James L.; Raney, David L.
2000-01-01
The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.
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F-15 PCA (Propulsion Controlled Aircraft) Simulation Cockpit
1990-01-01
The F-15 PCA (Propulsion Controlled Aircraft) simulation was used from 1990 to 1993. It was used for the development of propulsion algorithms and piloting techniques (using throttles only) to be used for emergency flight control in the advent of a major flight control system failure on a multi-engine aircraft. Following this program with the Dryden F-15, similiar capabilities were developed for other aircraft, such as the B-720, Lear 24, B-727, C-402, and B-747.
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Resilient controls for ordering uncertain prospects change and response
Pham, Khanh D
2014-01-01
Providing readers with a detailed examination of resilient controls in risk-averse decision, this monograph is aimed toward researchers and graduate students in applied mathematics and electrical engineering with a systems-theoretic concentration. This work contains a timely and responsive evaluation of reforms on the use of asymmetry or skewness pertaining to the restrictive family of quadratic costs that have been appeared in various scholarly forums. Additionally, the book includes a discussion of the current and ongoing efforts in the usage of risk, dynamic game decision optimization and disturbance mitigation techniques with output feedback measurements tailored toward the worst-case scenarios. This work encompasses some of the current changes across uncertainty quantification, stochastic control communities, and the creative efforts that are being made to increase the understanding of resilient controls. Specific considerations are made in this book for the application of decision theory to resilient ...
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Artificial Intelligence for Controlling Robotic Aircraft
Krishnakumar, Kalmanje
2005-01-01
A document consisting mostly of lecture slides presents overviews of artificial-intelligence-based control methods now under development for application to robotic aircraft [called Unmanned Aerial Vehicles (UAVs) in the paper] and spacecraft and to the next generation of flight controllers for piloted aircraft. Following brief introductory remarks, the paper presents background information on intelligent control, including basic characteristics defining intelligent systems and intelligent control and the concept of levels of intelligent control. Next, the paper addresses several concepts in intelligent flight control. The document ends with some concluding remarks, including statements to the effect that (1) intelligent control architectures can guarantee stability of inner control loops and (2) for UAVs, intelligent control provides a robust way to accommodate an outer-loop control architecture for planning and/or related purposes.
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Dynamics and control of robotic aircraft with articulated wings
Paranjape, Aditya Avinash
There is a considerable interest in developing robotic aircraft, inspired by birds, for a variety of missions covering reconnaissance and surveillance. Flapping wing aircraft concepts have been put forth in light of the efficiency of flapping flight at small scales. These aircraft are naturally equipped with the ability to rotate their wings about the root, a form of wing articulation. This thesis covers some problems concerning the performance, stability and control of robotic aircraft with articulated wings in gliding flight. Specifically, we are interested in aircraft without a vertical tail, which would then use wing articulation for longitudinal as well as lateral-directional control. Although the dynamics and control of articulated wing aircraft share several common features with conventional fixed wing aircraft, the presence of wing articulation presents several unique benefits as well as limitations from the perspective of performance and control. One of the objective of this thesis is to understand these features using a combination of theoretical and numerical tools. The aircraft concept envisioned in this thesis uses the wing dihedral angles for longitudinal and lateral-directional control. Aircraft with flexible articulated wings are also investigated. We derive a complete nonlinear model of the flight dynamics incorporating dynamic CG location and the changing moment of inertia. We show that symmetric dihedral configuration, along with a conventional horizontal tail, can be used to control flight speed and flight path angle independently of each other. This characteristic is very useful for initiating an efficient perching maneuver. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. We compute the turning performance limitations that arise due to the use of wing dihedral for yaw control
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Resilient guaranteed cost control of a power system.
Soliman, Hisham M; Soliman, Mostafa H; Hassan, Mohammad F
2014-05-01
With the development of power system interconnection, the low-frequency oscillation is becoming more and more prominent which may cause system separation and loss of energy to consumers. This paper presents an innovative robust control for power systems in which the operating conditions are changing continuously due to load changes. However, practical implementation of robust control can be fragile due to controller inaccuracies (tolerance of resistors used with operational amplifiers). A new design of resilient (non-fragile) robust control is given that takes into consideration both model and controller uncertainties by an iterative solution of a set of linear matrix inequalities (LMI). Both uncertainties are cast into a norm-bounded structure. A sufficient condition is derived to achieve the desired settling time for damping power system oscillations in face of plant and controller uncertainties. Furthermore, an improved controller design, resilient guaranteed cost controller, is derived to achieve oscillations damping in a guaranteed cost manner. The effectiveness of the algorithm is shown for a single machine infinite bus system, and then, it is extended to multi-area power system.
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Design of adaptive switching control for hypersonic aircraft
Directory of Open Access Journals (Sweden)
Xin Jiao
2015-10-01
Full Text Available This article proposes a novel adaptive switching control of hypersonic aircraft based on type-2 Takagi–Sugeno–Kang fuzzy sliding mode control and focuses on the problem of stability and smoothness in the switching process. This method uses full-state feedback to linearize the nonlinear model of hypersonic aircraft. Combining the interval type-2 Takagi–Sugeno–Kang fuzzy approach with sliding mode control keeps the adaptive switching process stable and smooth. For rapid stabilization of the system, the adaptive laws use a direct constructive Lyapunov analysis together with an established type-2 Takagi–Sugeno–Kang fuzzy logic system. Simulation results indicate that the proposed control scheme can maintain the stability and smoothness of switching process for the hypersonic aircraft.
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Schäfer, Judith; Wittchen, Hans-Ulrich; Höfler, Michael; Heinrich, Anke; Zimmermann, Peter; Siegel, Stefan; Schönfeld, Sabine
2015-09-01
Attentional processes have been suggested to play a crucial role in resilience defined as positive adaptation facing adversity. However, research is lacking on associations between attentional biases to positive and threat-related stimuli, attentional control and trait resilience. Data stem from the follow-up assessment of a longitudinal study investigating mental health and related factors among German soldiers. Trait resilience was assessed with the Connor-Davidson Resilience Scale and attentional control with the Attentional Control Scale. A subset of n = 198 soldiers also completed a dot probe task with happy, neutral and threatening faces. Attentional control was positively related to trait resilience. Results revealed no associations between both attentional biases and trait resilience. However, there was a negative association between attentional bias to threat and trait resilience when attentional control was low and a positive association between attentional bias to threat and trait resilience when attentional control was high. No such associations were found for attentional bias to positive stimuli. Generalizability to other populations may be limited since we exclusively focused on male soldiers. Also, the cross-sectional design does not allow for causal conclusions. Findings suggest that attentional processing may promote trait resilience. Future research on preventive interventions should consider these findings. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Bioelectric Control of a 757 Class High Fidelity Aircraft Simulation
Jorgensen, Charles; Wheeler, Kevin; Stepniewski, Slawomir; Norvig, Peter (Technical Monitor)
2000-01-01
This paper presents results of a recent experiment in fine grain Electromyographic (EMG) signal recognition, We demonstrate bioelectric flight control of 757 class simulation aircraft landing at San Francisco International Airport. The physical instrumentality of a pilot control stick is not used. A pilot closes a fist in empty air and performs control movements which are captured by a dry electrode array on the arm, analyzed and routed through a flight director permitting full pilot outer loop control of the simulation. A Vision Dome immersive display is used to create a VR world for the aircraft body mechanics and flight changes to pilot movements. Inner loop surfaces and differential aircraft thrust is controlled using a hybrid neural network architecture that combines a damage adaptive controller (Jorgensen 1998, Totah 1998) with a propulsion only based control system (Bull & Kaneshige 1997). Thus the 757 aircraft is not only being flown bioelectrically at the pilot level but also demonstrates damage adaptive neural network control permitting adaptation to severe changes in the physical flight characteristics of the aircraft at the inner loop level. To compensate for accident scenarios, the aircraft uses remaining control surface authority and differential thrust from the engines. To the best of our knowledge this is the first time real time bioelectric fine-grained control, differential thrust based control, and neural network damage adaptive control have been integrated into a single flight demonstration. The paper describes the EMG pattern recognition system and the bioelectric pattern recognition methodology.
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Control Design for a Generic Commercial Aircraft Engine
Csank, Jeffrey; May, Ryan D.
2010-01-01
This paper describes the control algorithms and control design process for a generic commercial aircraft engine simulation of a 40,000 lb thrust class, two spool, high bypass ratio turbofan engine. The aircraft engine is a complex nonlinear system designed to operate over an extreme range of environmental conditions, at temperatures from approximately -60 to 120+ F, and at altitudes from below sea level to 40,000 ft, posing multiple control design constraints. The objective of this paper is to provide the reader an overview of the control design process, design considerations, and justifications as to why the particular architecture and limits have been chosen. The controller architecture contains a gain-scheduled Proportional Integral controller along with logic to protect the aircraft engine from exceeding any limits. Simulation results illustrate that the closed loop system meets the Federal Aviation Administration s thrust response requirements
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Automatic control design procedures for restructurable aircraft control
Looze, D. P.; Krolewski, S.; Weiss, J.; Barrett, N.; Eterno, J.
1985-01-01
A simple, reliable automatic redesign procedure for restructurable control is discussed. This procedure is based on Linear Quadratic (LQ) design methodologies. It employs a robust control system design for the unfailed aircraft to minimize the effects of failed surfaces and to extend the time available for restructuring the Flight Control System. The procedure uses the LQ design parameters for the unfailed system as a basis for choosing the design parameters of the failed system. This philosophy alloys the engineering trade-offs that were present in the nominal design to the inherited by the restructurable design. In particular, it alloys bandwidth limitations and performance trade-offs to be incorporated in the redesigned system. The procedure also has several other desirable features. It effectively redistributes authority among the available control effectors to maximize the system performance subject to actuator limitations and constraints. It provides a graceful performance degradation as the amount of control authority lessens. When given the parameters of the unfailed aircraft, the automatic redesign procedure reproduces the nominal control system design.
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Flow Control Enabled Aircraft Design
National Research Council Canada - National Science Library
Nangia, Rajendar
2004-01-01
...: Many future advanced aircraft concepts being considered by the Air Force fall outside the current aerodynamic design practice and will rely heavily on the use of flow control technology to optimize flight performance...
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Longitudinal control of aircraft dynamics based on optimization of PID parameters
Deepa, S. N.; Sudha, G.
2016-03-01
Recent years many flight control systems and industries are employing PID controllers to improve the dynamic behavior of the characteristics. In this paper, PID controller is developed to improve the stability and performance of general aviation aircraft system. Designing the optimum PID controller parameters for a pitch control aircraft is important in expanding the flight safety envelope. Mathematical model is developed to describe the longitudinal pitch control of an aircraft. The PID controller is designed based on the dynamic modeling of an aircraft system. Different tuning methods namely Zeigler-Nichols method (ZN), Modified Zeigler-Nichols method, Tyreus-Luyben tuning, Astrom-Hagglund tuning methods are employed. The time domain specifications of different tuning methods are compared to obtain the optimum parameters value. The results prove that PID controller tuned by Zeigler-Nichols for aircraft pitch control dynamics is better in stability and performance in all conditions. Future research work of obtaining optimum PID controller parameters using artificial intelligence techniques should be carried out.
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Time-varying linear control for tiltrotor aircraft
Directory of Open Access Journals (Sweden)
Jing ZHANG
2018-04-01
Full Text Available Tiltrotor aircraft have three flight modes: helicopter mode, airplane mode, and transition mode. A tiltrotor has characteristics of highly nonlinear, time-varying flight dynamics and inertial/control couplings in its transition mode. It can transit from the helicopter mode to the airplane mode by tilting its nacelles, and an effective controller is crucial to accomplish tilting transition missions. Longitudinal dynamic characteristics of the tiltrotor are described by a nonlinear Lagrange-form model, which takes into account inertial/control couplings and aerodynamic interferences. Reference commands for airspeed velocity and attitude in the transition mode are calculated dynamically by visiting a command library which is founded in advance by analyzing the flight envelope of the tiltrotor. A Time-Varying Linear (TVL model is obtained using a Taylor-expansion based online linearization technique from the nonlinear model. Subsequently, based on an optimal control concept, an online optimization based control method with input constraints considered is proposed. To validate the proposed control method, three typical tilting transition missions are simulated using the nonlinear model of XV-15 tiltrotor aircraft. Simulation results show that the controller can be used to control the tiltrotor throughout its operating envelop which includes a transition flight, and can also deal with vertical gust disturbances. Keywords: Constrained optimal control, Inertia/control couplings, Tiltrotor aircraft, Time-varying control, Transition mode
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Real-time monitoring, prognosis, and resilient control for wind turbine systems
Energy Technology Data Exchange (ETDEWEB)
Gao, Zhiwei; Sheng, Shuangwen
2018-02-01
This special issue aims to provide a platform for academic and industrial communities to report recent results and emerging research in real-time monitoring, fault diagnosis, prognosis, and resilient control and design of wind turbine systems. After a strict peer-review process, 20 papers were selected, which represent the most recent progress of the real-time monitoring, diagnosis, prognosis, and resilient control methods/techniques in wind turbine systems.
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Stability Result For Dynamic Inversion Devised to Control Large Flexible Aircraft
Gregory, Irene M.
2001-01-01
High performance aircraft of the future will be designed lighter, more maneuverable, and operate over an ever expanding flight envelope. One of the largest differences from the flight control perspective between current and future advanced aircraft is elasticity. Over the last decade, dynamic inversion methodology has gained considerable popularity in application to highly maneuverable fighter aircraft, which were treated as rigid vehicles. This paper is an initial attempt to establish global stability results for dynamic inversion methodology as applied to a large, flexible aircraft. This work builds on a previous result for rigid fighter aircraft and adds a new level of complexity that is the flexible aircraft dynamics, which cannot be ignored even in the most basic flight control. The results arise from observations of the control laws designed for a new generation of the High-Speed Civil Transport aircraft.
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Global Tracking Control of Quadrotor VTOL Aircraft in Three-Dimensional Space
Directory of Open Access Journals (Sweden)
Duc Khac Do
2014-07-01
Full Text Available This paper presents a method to design controllers that force a quadrotor vertical take-off and landing (VTOL aircraft to globally asymptotically track a reference trajectory in three-dimensional space. Motivated by the vehicle's steering practice, the roll and pitch angles are considered as immediate controls plus the total thrust force provided by the aircraft's four rotors to control the position and yaw angle of the aircraft. The control design is based on the newly introduced one-step ahead backstepping, the standard backstepping and Lyapunov's direct methods. A combination of Euler angles and unit-quaternion for the attitude representation of the aircraft is used to obtain global tracking control results. The paper also includes a design of observers that exponentially estimate the aircraft's linear velocity vector and disturbances. Simulations illustrate the results.
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Total aircraft flight-control system - Balanced open- and closed-loop control with dynamic trim maps
Smith, G. A.; Meyer, G.
1979-01-01
The availability of the airborne digital computer has made possible a Total Aircraft Flight Control System (TAFCOS) that uses virtually the complete nonlinear propulsive and aerodynamic data for the aircraft to construct dynamic trim maps that represent an inversion of the aircraft model. The trim maps, in series with the aircraft, provide essentially a linear feed-forward path. Basically, open-loop trajectory control is employed with only a small perturbation feedback signal required to compensate for inaccuracy in the aircraft model and for external disturbances. Simulation results for application to an automatic carrier-landing system are presented. Flight-test results for a STOL aircraft operating automatically over a major portion of its flight regime are presented. The concept promises a more rapid and straightforward design from aerodynamic principles, particularly for highly nonlinear configurations, and requires substantially less digital computer capacity than conventional automatic flight-control system designs.
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Aircraft digital flight control technical review
Davenport, Otha B.; Leggett, David B.
1993-01-01
The Aircraft Digital Flight Control Technical Review was initiated by two pilot induced oscillation (PIO) incidents in the spring and summer of 1992. Maj. Gen. Franklin (PEO) wondered why the Air Force development process for digital flight control systems was not preventing PIO problems. Consequently, a technical review team was formed to examine the development process and determine why PIO problems continued to occur. The team was also to identify the 'best practices' used in the various programs. The charter of the team was to focus on the PIO problem, assess the current development process, and document the 'best practices.' The team reviewed all major USAF aircraft programs with digital flight controls, specifically, the F-15E, F-16C/D, F-22, F-111, C-17, and B-2. The team interviewed contractor, System Program Office (SPO), and Combined Test Force (CTF) personnel on these programs. The team also went to NAS Patuxent River to interview USN personnel about the F/A-18 program. The team also reviewed experimental USAF and NASA systems with digital flight control systems: X-29, X-31, F-15 STOL and Maneuver Technology Demonstrator (SMTD), and the Variable In-Flight Stability Test Aircraft (VISTA). The team also discussed the problem with other experts in the field including Ralph Smith and personnel from Calspan. The major conclusions and recommendations from the review are presented.
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Future Integrated Systems Concept for Preventing Aircraft Loss-of-Control Accidents
Belcastro, Christine M.; Jacobson, Steven r.
2010-01-01
Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper presents future system concepts and research directions for preventing aircraft loss-of-control accidents.
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Safety assurance of non-deterministic flight controllers in aircraft applications
Noriega, Alfonso
Loss of control is a serious problem in aviation that primarily affects General Aviation. Technological advancements can help mitigate the problem, but the FAA certification process makes certain solutions economically unfeasible. This investigation presents the design of a generic adaptive autopilot that could potentially lead to a single certification for use in several makes and models of aircraft. The autopilot consists of a conventional controller connected in series with a robust direct adaptive model reference controller. In this architecture, the conventional controller is tuned once to provide outer-loop guidance and navigation to a reference model. The adaptive controller makes unknown aircraft behave like the reference model, allowing the conventional controller to successfully provide navigation without the need for retuning. A strong theoretical foundation is presented as an argument for the safety and stability of the controller. The stability proof of direct adaptive controllers require that the plant being controlled has no unstable transmission zeros and has a nonzero high frequency gain. Because most conventional aircraft do not readily meet these requirements, a process known as sensor blending was used. Sensor blending consists of using a linear combination of the plant's outputs that has no unstable transmission zeros and has a nonzero high frequency gain to drive the adaptive controller. Although this method does not present a problem for regulators, it can lead to a steady state error in tracking applications. The sensor blending theory was expanded to take advantage of the system's dynamics to allow for zero steady state error tracking. This method does not need knowledge of the specific system's dynamics, but instead uses the structure of the A and B matrices to perform the blending for the general case. The generic adaptive autopilot was tested in two high-fidelity nonlinear simulators of two typical General Aviation aircraft. The results
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Fate control and well-being in Chinese rural people living with HIV: mediation effect of resilience.
Yu, Nancy Xiaonan; Zhang, Jianxin; Chow, Amy Y M; Chan, Celia H Y; Chan, Cecilia L W
2017-01-01
Fate control has been often misconceptualized as a superstitious belief and overlooked in health psychology. It is not known how this cultural belief might impact the well-being of Chinese people living with HIV. This study examined the protective role of fate control for well-being and the potential mediation effect of resilience. Participants in this study were rural patients who contracted HIV via commercial blood donation. In this cross-sectional survey, 250 participants completed measures of fate control, well-being, and resilience. The results showed that fate control and resilience were positively associated with well-being. Resilience mediated the association between fate control and well-being. Our findings provide insight into the adaptive function of fate control as a cognitive defensive mechanism and highlight the need to incorporate this cultural belief in developing culturally sensitive intervention programs for resilience enhancement tailored for this understudied population infected with HIV living in rural China.
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Mapping automotive like controls to a general aviation aircraft
Carvalho, Christopher G.
The purpose of this thesis was to develop fly-by-wire control laws enabling a general aviation aircraft to be flown with automotive controls, i.e. a steering wheel and gas/brake pedals. There was a six speed shifter used to change the flight mode of the aircraft. This essentially allows the pilot to have control over different aspects of the flight profile such as climb/descend or cruise. A highway in the sky was used to aid in the navigation since it is not intuitive to people without flight experience how to navigate from the sky or when to climb and descend. Many believe that general aviation could become as widespread as the automobile. Every person could have a personal aircraft at their disposal and it would be as easy to operate as driving an automobile. The goal of this thesis is to fuse the ease of drivability of a car with flight of a small general aviation aircraft. A standard automotive control hardware setup coupled with variably autonomous control laws will allow new pilots to fly a plane as easily as driving a car. The idea is that new pilots will require very little training to become proficient with these controls. Pilots with little time to stay current can maintain their skills simply by driving a car which is typically a daily activity. A human factors study was conducted to determine the feasibility of the applied control techniques. Pilot performance metrics were developed to compare candidates with no aviation background and experienced pilots. After analyzing the relative performance between pilots and non-pilots, it has been determined that the control system is robust and easy to learn. Candidates with no aviation experience whatsoever can learn to fly an aircraft as safely and efficiently as someone with hundreds of hours of flight experience using these controls.
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A Risk Management Architecture for Emergency Integrated Aircraft Control
McGlynn, Gregory E.; Litt, Jonathan S.; Lemon, Kimberly A.; Csank, Jeffrey T.
2011-01-01
Enhanced engine operation--operation that is beyond normal limits--has the potential to improve the adaptability and safety of aircraft in emergency situations. Intelligent use of enhanced engine operation to improve the handling qualities of the aircraft requires sophisticated risk estimation techniques and a risk management system that spans the flight and propulsion controllers. In this paper, an architecture that weighs the risks of the emergency and of possible engine performance enhancements to reduce overall risk to the aircraft is described. Two examples of emergency situations are presented to demonstrate the interaction between the flight and propulsion controllers to facilitate the enhanced operation.
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Energy Technology Data Exchange (ETDEWEB)
Rodrigues de Carvalho, Paulo Victor, E-mail: paulov@ien.gov.br [National Nuclear Energy Commission/Nuclear Engineering Institute, Cidade Universitaria-Ilha do Fundao, Rio de Janeiro, RJ 21945-970 (Brazil)
2011-11-15
The Functional Resonance Analysis Model (FRAM) defines a systemic framework to model complex systems for accident analysis purposes. We use FRAM in the mid-air collision between flight GLO1907, a commercial aircraft Boeing 737-800, and flight N600XL, an executive jet EMBRAER E-145, to investigate key resilience characteristics of the Air Traffic Management System (ATM). This ATM system related accident occurred at 16:56 Brazilian time on September 29, 2006 in the Amazonian sky. FRAM analysis of flight monitoring functions showed system constraints (equipment, training, time, and supervision) that produce variability in system behavior, creating demand resources mismatches in an attempt to perceive and control the developing situation. This variability also included control and coordination breakdowns and automation surprises (TCAS functioning). The analysis showed that under normal variability conditions (without catastrophic failures) the ATM system (pilots, controllers, supervisors, and equipment) was not able to close the control loops of the flight monitoring functions using feedback or feedforward strategies to achieve an adequate control of an aircraft flying in the controlled air space. Our findings shed some light on the resilience of Brazilian ATM system operation and indicated that there is a need of a deeper understanding on how the system is actually functioning. - Highlights: > The Functional Resonance Analysis Model (FRAM) was used in a mid-air collision over Amazon. > The aim was to understand key resilience characteristics of the Air Traffic Management System (ATM). > The analysis showed how, under normal conditions, the system was not able to control flight functions. > The findings shed some light about the resilience of Brazilian ATM system operation.
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International Nuclear Information System (INIS)
Rodrigues de Carvalho, Paulo Victor
2011-01-01
The Functional Resonance Analysis Model (FRAM) defines a systemic framework to model complex systems for accident analysis purposes. We use FRAM in the mid-air collision between flight GLO1907, a commercial aircraft Boeing 737-800, and flight N600XL, an executive jet EMBRAER E-145, to investigate key resilience characteristics of the Air Traffic Management System (ATM). This ATM system related accident occurred at 16:56 Brazilian time on September 29, 2006 in the Amazonian sky. FRAM analysis of flight monitoring functions showed system constraints (equipment, training, time, and supervision) that produce variability in system behavior, creating demand resources mismatches in an attempt to perceive and control the developing situation. This variability also included control and coordination breakdowns and automation surprises (TCAS functioning). The analysis showed that under normal variability conditions (without catastrophic failures) the ATM system (pilots, controllers, supervisors, and equipment) was not able to close the control loops of the flight monitoring functions using feedback or feedforward strategies to achieve an adequate control of an aircraft flying in the controlled air space. Our findings shed some light on the resilience of Brazilian ATM system operation and indicated that there is a need of a deeper understanding on how the system is actually functioning. - Highlights: → The Functional Resonance Analysis Model (FRAM) was used in a mid-air collision over Amazon. → The aim was to understand key resilience characteristics of the Air Traffic Management System (ATM). → The analysis showed how, under normal conditions, the system was not able to control flight functions. → The findings shed some light about the resilience of Brazilian ATM system operation.
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Adaptive Feedfoward Feedback Control Framework, Phase I
National Aeronautics and Space Administration — A novel approach is proposed for the suppression of the aircraft's structural vibration to increase the resilience of the flight control law in the presence of the...
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Selected Aircraft Throttle Controller With Support Of Fuzzy Expert Inference System
Directory of Open Access Journals (Sweden)
Żurek Józef
2014-12-01
Full Text Available The paper describes Zlin 143Lsi aircraft engine work parameters control support method – hourly fuel flow as a main factor under consideration. The method concerns project of aircraft throttle control support system with use of fuzzy logic (fuzzy inference. The primary purpose of the system is aircraft performance optimization, reducing flight cost at the same time and support proper aircraft engine maintenance. Matlab Software and Fuzzy Logic Toolbox were used in the project. Work of the system is presented with use of twenty test samples, five of them are presented graphically. In addition, system control surface, included in the paper, supports system all work range analysis.
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Knowledge-based processing for aircraft flight control
Painter, John H.; Glass, Emily; Economides, Gregory; Russell, Paul
1994-01-01
This Contractor Report documents research in Intelligent Control using knowledge-based processing in a manner dual to methods found in the classic stochastic decision, estimation, and control discipline. Such knowledge-based control has also been called Declarative, and Hybid. Software architectures were sought, employing the parallelism inherent in modern object-oriented modeling and programming. The viewpoint adopted was that Intelligent Control employs a class of domain-specific software architectures having features common over a broad variety of implementations, such as management of aircraft flight, power distribution, etc. As much attention was paid to software engineering issues as to artificial intelligence and control issues. This research considered that particular processing methods from the stochastic and knowledge-based worlds are duals, that is, similar in a broad context. They provide architectural design concepts which serve as bridges between the disparate disciplines of decision, estimation, control, and artificial intelligence. This research was applied to the control of a subsonic transport aircraft in the airport terminal area.
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Imaged-Based Visual Servo Control for a VTOL Aircraft
Directory of Open Access Journals (Sweden)
Liying Zou
2017-01-01
Full Text Available This paper presents a novel control strategy to force a vertical take-off and landing (VTOL aircraft to accomplish the pinpoint landing task. The control development is based on the image-based visual servoing method and the back-stepping technique; its design differs from the existing methods because the controller maps the image errors onto the actuator space via a visual model which does not contain the depth information of the feature point. The novelty of the proposed method is to extend the image-based visual servoing technique to the VTOL aircraft control. In addition, the Lyapunov theory is used to prove the asymptotic stability of the VTOL aircraft visual servoing system, while the image error can converge to zero. Furthermore, simulations have been also conducted to demonstrate the performances of the proposed method.
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Human Factors and Data Fusion as Part of Control Systems Resilience
Energy Technology Data Exchange (ETDEWEB)
David I. Gertman
2009-05-01
Human performance and human decision making is counted upon as a crucial aspect of overall system resilience. Advanced control systems have the potential to provide operators and asset owners a wide range of data, deployed at different levels that can be used to support operator situation awareness. However, the sheer amount of data available can make it challenging for operators to assimilate information and respond appropriately. This paper reviews some of the challenges and issues associated with providing operators with actionable state awareness and argues for the over arching importance of integrating human factors as part of intelligent control systems design and implementation. It is argued that system resilience is improved by implementing human factors in operations and maintenance. This paper also introduces issues associated with resilience and data fusion and highlights areas in which human factors including field studies hold promise.
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Anomaly Detection for Resilient Control Systems Using Fuzzy-Neural Data Fusion Engine
Energy Technology Data Exchange (ETDEWEB)
Ondrej Linda; Milos Manic; Timothy R. McJunkin
2011-08-01
Resilient control systems in critical infrastructures require increased cyber-security and state-awareness. One of the necessary conditions for achieving the desired high level of resiliency is timely reporting and understanding of the status and behavioral trends of the control system. This paper describes the design and development of a neural-network based data-fusion system for increased state-awareness of resilient control systems. The proposed system consists of a dedicated data-fusion engine for each component of the control system. Each data-fusion engine implements three-layered alarm system consisting of: (1) conventional threshold-based alarms, (2) anomalous behavior detector using self-organizing maps, and (3) prediction error based alarms using neural network based signal forecasting. The proposed system was integrated with a model of the Idaho National Laboratory Hytest facility, which is a testing facility for hybrid energy systems. Experimental results demonstrate that the implemented data fusion system provides timely plant performance monitoring and cyber-state reporting.
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Resilient distributed control in the presence of misbehaving agents in networked control systems.
Zeng, Wente; Chow, Mo-Yuen
2014-11-01
In this paper, we study the problem of reaching a consensus among all the agents in the networked control systems (NCS) in the presence of misbehaving agents. A reputation-based resilient distributed control algorithm is first proposed for the leader-follower consensus network. The proposed algorithm embeds a resilience mechanism that includes four phases (detection, mitigation, identification, and update), into the control process in a distributed manner. At each phase, every agent only uses local and one-hop neighbors' information to identify and isolate the misbehaving agents, and even compensate their effect on the system. We then extend the proposed algorithm to the leaderless consensus network by introducing and adding two recovery schemes (rollback and excitation recovery) into the current framework to guarantee the accurate convergence of the well-behaving agents in NCS. The effectiveness of the proposed method is demonstrated through case studies in multirobot formation control and wireless sensor networks.
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Neutron radiography of aircraft composite flight control surfaces
International Nuclear Information System (INIS)
Lewis, W.J.; Bennett, L.G.I.; Chalovich, T.R.; Francescone, O.
2001-01-01
A small (20 kWth), safe, pool-type nuclear research reactor called the SLOWPOKE-2 is located at the Royal Military College of Canada (RMC). The reactor was originally installed for teaching, training, research and semi-routine analysis, specifically, neutron activation analysis. It was envisioned that the neutrons from the SLOWPOKE-2 could also be used for neutron radiography, and so a research program was initiated to develop this technology. Over a period of approximately 15 years, and through a series of successive modifications, a neutron radiography system (NRS) was developed. Once completed, several applications of the technology have been demonstrated, including the nondestructive examination of the composite flight control surfaces from the Canadian Air Force's primary jet fighter, the CF18 Hornet aircraft. An initial trial was setup to investigate the flight control surfaces of 3 aircraft, to determine the parameters for a final licensed system, and to compare the results to other nondestructive methods. Over 500 neutron radiographs were made for these first 3 aircraft, and moisture and corrosion were discovered in the honeycomb structure and hydration was found in the composite and adhesive layers. In comparison with other NDT methods, neutron radiography was the only method that could detect the small areas of corrosion and moisture entrapment. However, before examining an additional 7 aircraft, the recommended modifications to the NRS were undertaken. These modifications were necessary to accommodate the larger flight control surfaces safely by incorporating flexible conformable shielding. As well, to expedite inspections so that all flight control surfaces from one aircraft could be completed in less than two weeks, there was a need to decrease the exposure time by both faster film/conversion screen combinations and by incorporating the capability of near realtime, digital radioscopy. Finally, as there are no inspection specific image quality
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Calise, A. J.; Kadushin, I.; Kramer, F.
1981-01-01
The current status of research on the application of variable structure system (VSS) theory to design aircraft flight control systems is summarized. Two aircraft types are currently being investigated: the Augmentor Wing Jet STOL Research Aircraft (AWJSRA), and AV-8A Harrier. The AWJSRA design considers automatic control of longitudinal dynamics during the landing phase. The main task for the AWJSRA is to design an automatic landing system that captures and tracks a localizer beam. The control task for the AV-8A is to track velocity commands in a hovering flight configuration. Much effort was devoted to developing computer programs that are needed to carry out VSS design in a multivariable frame work, and in becoming familiar with the dynamics and control problems associated with the aircraft types under investigation. Numerous VSS design schemes were explored, particularly for the AWJSRA. The approaches that appear best suited for these aircraft types are presented. Examples are given of the numerical results currently being generated.
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An Integrated Approach to Aircraft Modelling and Flight Control Law Design
Looye, G.H.N.
2008-01-01
The design of flight control laws (FCLs) for automatic and manual (augmented) control of aircraft is a complicated task. FCLs have to fulfil large amounts of performance criteria and must work reliably in all flight conditions, for all aircraft configurations, and in adverse weather conditions.
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Maneuvering control and configuration adaptation of a biologically inspired morphing aircraft
Abdulrahim, Mujahid
Natural flight as a source of inspiration for aircraft design was prominent with early aircraft but became marginalized as aircraft became larger and faster. With recent interest in small unmanned air vehicles, biological inspiration is a possible technology to enhance mission performance of aircraft that are dimensionally similar to gliding birds. Serial wing joints, loosely modeling the avian skeletal structure, are used in the current study to allow significant reconfiguration of the wing shape. The wings are reconfigured to optimize aerodynamic performance and maneuvering metrics related to specific mission tasks. Wing shapes for each mission are determined and related to the seagulls, falcons, albatrosses, and non-migratory African swallows on which the aircraft are based. Variable wing geometry changes the vehicle dynamics, affording versatility in flight behavior but also requiring appropriate compensation to maintain stability and controllability. Time-varying compensation is in the form of a baseline controller which adapts to both the variable vehicle dynamics and to the changing mission requirements. Wing shape is adapted in flight to minimize a cost function which represents energy, temporal, and spatial efficiency. An optimal control architecture unifies the control and adaptation tasks.
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Depressive Symptoms and Resilience among Pregnant Adolescents: A Case-Control Study
Directory of Open Access Journals (Sweden)
Danny Salazar-Pousada
2010-01-01
Full Text Available Background. Data regarding depression and resilience among adolescents is still lacking. Objective. To assess depressive symptoms and resilience among pregnant adolescents. Method. Depressive symptoms and resilience were assessed using two validated inventories, the 10-item Center for Epidemiologic Studies Short Depression Scale (CESD-10 and the 14-item Wagnild and Young Resilience Scale (RS, respectively. A case-control approach was used to compare differences between adolescents and adults. Results. A total of 302 pregnant women were enrolled in the study, 151 assigned to each group. Overall, 56.6% of gravids presented total CESD-10 scores 10 or more indicating depressed mood. Despite this, total CESD-10 scores and depressed mood rate did not differ among studied groups. Adolescents did however display lower resilience reflected by lower total RS scores and a higher rate of scores below the calculated median (P<.05. Logistic regression analysis could not establish any risk factor for depressed mood among studied subjects; however, having an adolescent partner (OR, 2.0 CI 95% 1.06–4.0, P=.03 and a preterm delivery (OR, 3.0 CI 95% 1.43–6.55, P=.004 related to a higher risk for lower resilience. Conclusion. In light of the findings of the present study, programs oriented at giving adolescents support before, during, and after pregnancy should be encouraged.
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Aircraft Turbine Engine Control Research at NASA Glenn Research Center
Garg, Sanjay
2014-01-01
This lecture will provide an overview of the aircraft turbine engine control research at NASA (National Aeronautics and Space Administration) Glenn Research Center (GRC). A brief introduction to the engine control problem is first provided with a description of the current state-of-the-art control law structure. A historical aspect of engine control development since the 1940s is then provided with a special emphasis on the contributions of GRC. The traditional engine control problem has been to provide a means to safely transition the engine from one steady-state operating point to another based on the pilot throttle inputs. With the increased emphasis on aircraft safety, enhanced performance and affordability, and the need to reduce the environmental impact of aircraft, there are many new challenges being faced by the designers of aircraft propulsion systems. The Controls and Dynamics Branch (CDB) at GRC is leading and participating in various projects in partnership with other organizations within GRC and across NASA, other government agencies, the U.S. aerospace industry, and academia to develop advanced propulsion controls and diagnostics technologies that will help meet the challenging goals of NASA programs under the Aeronautics Research Mission. The second part of the lecture provides an overview of the various CDB technology development activities in aircraft engine control and diagnostics, both current and some accomplished in the recent past. The motivation for each of the research efforts, the research approach, technical challenges and the key progress to date are summarized. The technologies to be discussed include system level engine control concepts, gas path diagnostics, active component control, and distributed engine control architecture. The lecture will end with a futuristic perspective of how the various current technology developments will lead to an Intelligent and Autonomous Propulsion System requiring none to very minimum pilot interface
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National Aeronautics and Space Administration — Resilient Ops, working in collaboration with Metron Aviation, Inc., proposes to develop a prototype system for planning Unmanned Aircraft Systems (UAS) trajectories...
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Application of AI methods to aircraft guidance and control
Hueschen, Richard M.; Mcmanus, John W.
1988-01-01
A research program for integrating artificial intelligence (AI) techniques with tools and methods used for aircraft flight control system design, development, and implementation is discussed. The application of the AI methods for the development and implementation of the logic software which operates with the control mode panel (CMP) of an aircraft is presented. The CMP is the pilot control panel for the automatic flight control system of a commercial-type research aircraft of Langley Research Center's Advanced Transport Operating Systems (ATOPS) program. A mouse-driven color-display emulation of the CMP, which was developed with AI methods and used to test the AI software logic implementation, is discussed. The operation of the CMP was enhanced with the addition of a display which was quickly developed with AI methods. The display advises the pilot of conditions not satisfied when a mode does not arm or engage. The implementation of the CMP software logic has shown that the time required to develop, implement, and modify software systems can be significantly reduced with the use of the AI methods.
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Eisenberg, Nancy; Chang, Lei; Ma, Yue; Huang, Xiaorui
2009-01-01
The purpose of the study was to examine the relations of authoritative parenting and corporal punishment to Chinese first and second graders' effortful control (EC), impulsivity, ego resilience, and maladjustment, as well as mediating relations. A parent and teacher reported on children's EC, impulsivity, and ego resilience; parents reported on children's internalizing symptoms and their own parenting, and teachers and peers reported on children's externalizing symptoms. Authoritative parenting and low corporal punishment predicted high EC, and EC mediated the relation between parenting and externalizing problems. In addition, impulsivity mediated the relation of corporal punishment to externalizing problems. The relation of parenting to children's ego resilience was mediated by EC and/or impulsivity, and ego resilience mediated the relations of EC and impulsivity to internalizing problems.
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Dray, Julia; Bowman, Jenny; Freund, Megan; Campbell, Elizabeth; Wolfenden, Luke; Hodder, Rebecca K; Wiggers, John
2014-07-18
Research investigating the effectiveness of universal interventions to reduce the risk of mental health problems remains limited. Schools are a promising setting within which adolescents can receive interventions aimed at promoting their mental health. The aim of this study is to assess the effectiveness of a resilience-based prevention-focused intervention in reducing the risk of mental health problems among adolescents attending secondary school in socio-economically disadvantaged areas. A cluster randomised control trial will be conducted, with schools as the unit of randomisation. Initially, 32 secondary schools will be randomly allocated to a control or intervention group (12 control and 20 intervention). An intervention focused on improving student internal and external resilience factors will be implemented in intervention schools. A survey of students in Grade 7 in both intervention and control schools will be conducted (baseline) and repeated three years later when the students are in Grade 10. The Strengths and Difficulties Questionnaire will be used to measure the risk of mental health problems. At follow-up, the risk of mental health problems will be compared between Grade 10 students in intervention and control schools to determine intervention effectiveness. The study presents an opportunity to determine the effectiveness of a comprehensive resilience-based intervention in reducing the risk of mental health problems in adolescents attending secondary schools. The outcomes of the trial are of importance to youth, schools, mental health clinicians and policymakers. Australian New Zealand Clinical Trials Registry, ACTRN12611000606987, registered 14 June 2011.
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Self-Guided Multimedia Stress Management and Resilience Training for Flight Controllers
Rose, R. D.; Zbozinek, T. D.; Hentschel, P. G.; Smith, S, M.; O'Brien J.; Oftedal, A.; Craske, M. G.
2016-01-01
Stress and anxiety-related problems are among the most common and costly behavioral health problems in society, and for those working in operational environments (i.e. astronauts, flight controllers, military) this can seriously impact crew performance, safety, and wellbeing. Technology-based interventions are effective for treating behavioral health problems, and can significantly improve the delivery of evidence-based health care. This study is evaluating the effectiveness, usefulness, and usability of a self-guided multimedia stress management and resilience training program in a randomized controlled trial (RCT) with a sample of flight controllers at Johnson Space Center. The intervention, SMART-OP (Stress Management and Resilience Training for Optimal Performance), is a six-session, cognitive behavioral-based computer program that uses self-guided, interactive activities to teach skills that can help individuals build resilience and manage stress. In a prior RCT with a sample of stressed but otherwise healthy individuals, SMART-OP reduced perceived stress and increased perceived control over stress in comparison to an Attention Control (AC) group. SMART-OP was rated as "highly useful" and "excellent" in usability and acceptability. Based on a-amylase data, individuals in SMART-OP recovered quicker and more completely from a social stress test as compared to the AC group [1]. In the current study, flight controllers are randomized either to receive SMART-OP training, or to a 6-week waitlist control period (WLC) before beginning SMART-OP. Eligible participants include JSC flight controllers and instructors without any medical or psychiatric disorder, but who are stressed based on self-report. Flight controllers provide a valid analog sample to astronauts in that they work in an operational setting, use similar terminology to astronauts, are mission-focused, and work under the same broader work culture. The study began in December 2014, and to date 79 flight
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Resilience versus "Resilient Individual": What Exactly Do We Study?
Directory of Open Access Journals (Sweden)
Jan Sebastian Novotný
2014-07-01
Full Text Available The nature and definition of resilience, despite the extensive 40 years of research, is still unclear. Currently is resilience seen as a personality trait, sum of the traits/factors, result of adaptation, or as a process. The concept of resilience as personality traits is usually tied to uni-dimensional or "simplex" theories of resistance as Hardiness, Sense of Control, Ego-Resiliency, Self-efficacy, Sense of Coherence, or specific personality traits. Multidimensional concepts see resilience as a complex of personality and social (environmental factors that work in interaction, complement or replace each other, and, in aggregate, create a comprehensive picture of resilience. The concept of resilience as the result of adaptation examines resilience in terms of the presence/absence of adverse/pathological manifestations, consequences and outcomes in relation to the earlier effect of stressful, risky or otherwise unfavorable situations. Finally, the concept of resilience as the process examines individual's response to risk factors or wounds that are present in the environment. Resilience is thus a process consisting of interactions between individual characteristics and the environment. Most experts and a large part of resilience research is based on the first three concepts that however explore how "resilient" the individual is rather than resilience itself, since they are based on "diagnosing" or at best dimensional, at worse dichotomous rating of the individual's resilience (within personality trait approach, or on the evaluation of the presence/absence of factors/source of resilience, thereby they are still holding the "diagnostic" approach (within multidimensional approach. Only the examination of processes, such as the ongoing interaction between these risk factors, resilience factors, outcomes (expressions of personality, behavior, presence of problems, etc. and other variables allows us to understand resilience (the true nature of how
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In-flight Fault Detection and Isolation in Aircraft Flight Control Systems
Azam, Mohammad; Pattipati, Krishna; Allanach, Jeffrey; Poll, Scott; Patterson-Hine, Ann
2005-01-01
In this paper we consider the problem of test design for real-time fault detection and isolation (FDI) in the flight control system of fixed-wing aircraft. We focus on the faults that are manifested in the control surface elements (e.g., aileron, elevator, rudder and stabilizer) of an aircraft. For demonstration purposes, we restrict our focus on the faults belonging to nine basic fault classes. The diagnostic tests are performed on the features extracted from fifty monitored system parameters. The proposed tests are able to uniquely isolate each of the faults at almost all severity levels. A neural network-based flight control simulator, FLTZ(Registered TradeMark), is used for the simulation of various faults in fixed-wing aircraft flight control systems for the purpose of FDI.
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2012-10-31
... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 87 [EPA-HQ-OAR-2010-0687; FRL-9678-1] RIN 2060-AO70 Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures Correction In rule document 2012-13828 appearing on pages 36341-36386 in the issue of Monday, June 18, 2012, make the following corrections: Sec. 87.2...
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Adaptive Backstepping Flight Control for Modern Fighter Aircraft
Sonneveldt, L.
2010-01-01
The main goal of this thesis is to investigate the potential of the nonlinear adaptive backstepping control technique in combination with online model identification for the design of a reconfigurable flight control system for a modern fighter aircraft. Adaptive backstepping is a recursive,
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Structural Acoustic Characteristics of Aircraft and Active Control of Interior Noise
Fuller, C. R.
1998-01-01
The reduction of aircraft cabin sound levels to acceptable values still remains a topic of much research. The use of conventional passive approaches has been extensively studied and implemented. However performance limits of these techniques have been reached. In this project, new techniques for understanding the structural acoustic behavior of aircraft fuselages and the use of this knowledge in developing advanced new control approaches are investigated. A central feature of the project is the Aircraft Fuselage Test Facility at Va Tech which is based around a full scale Cessna Citation III fuselage. The work is divided into two main parts; the first part investigates the use of an inverse technique for identifying dominant fuselage vibrations. The second part studies the development and implementation of active and active-passive techniques for controlling aircraft interior noise.
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Pivoting output unit control systems activated by jacks. [for controlling aircraft flaps
Belliere, P.
1978-01-01
An invention to be used for controlling aircraft flaps is described. It is applicable to control systems with two coaxial output units which pivot simultaneously with respect to two fixed units and which are activated by two opposed, straight coaxial jacks.
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Software-in-the-loop simulation of a quadcopter portion for hybrid aircraft control
Mansoor, Shoaib; Saedan, Mana
2018-01-01
In this paper, we present the design of the software-in-the-loop simulation framework for a quadcopter that is incorporated in our hybrid aircraft. The hybrid aircraft comprises a quad-copter and a fixed wing with one forward thrust rotor. We need to develop a split control system that utilizes a typical quadcopter controller to control four motors/propellers and a supervisor controller to control a forward thrust rotor. The supervisor controller shall take feedback signals from the quadcopter and will command the fifth rotor for stabilizing the hybrid aircraft and resolves problems like thrust saturation. The simulation simulates the control algorithm and verifies the quadcopter’s behavior using MATLAB and Simulink together. Achieving these results, we come to know how our hybrid controller will be implemented, what results to expect once the forward thrust rotor is attached to the quadcopter. The software-in-the-loop simulation of a quadcopter is one of the most effective methods for verifying overall control performance and safety of the hybrid aircraft before actual hardware implementation and flight test.
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Effects of Flood Control Strategies on Flood Resilience Under Sociohydrological Disturbances
Sung, Kyungmin; Jeong, Hanseok; Sangwan, Nikhil; Yu, David J.
2018-04-01
A community capacity to cope with flood hazards, or community flood resilience, emerges from the interplay of hydrological and social processes. This interplay can be significantly influenced by the flood control strategy adopted by a society, i.e., how a society sets its desired flood protection level and strives to achieve this goal. And this interplay can be further complicated by rising land-sea level differences, seasonal water level fluctuations, and economic change. But not much research has been done on how various forms of flood control strategies affect human-flood interactions under these disturbances and therefore flood resilience in the long run. The current study is an effort to address these issues by developing a conceptual model of human-flood interaction mediated by flood control strategies. Our model extends the existing model of Yu et al. (2017), who investigated the flood resilience of a community-based flood protection system in coastal Bangladesh. The major extensions made in this study are inclusions of various forms of flood control strategies (both adaptive and nonadaptive ones), the challenge of rising land-sea level differences, and various high tide level scenarios generated from modifying the statistical variances and averages. Our results show that adaptive forms of flood control strategies tend to outperform nonadaptive ones for maintaining the model community's flood protection system. Adaptive strategies that dynamically adjust target flood protection levels through close monitoring of flood damages and social memories of flood risk can help the model community deal with various disturbances.
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Active Structural Control for Aircraft Efficiency with the X-56A Aircraft
Ouellette, Jeffrey
2015-01-01
The X-56A Multi-Utility Technology Testbed is an experimental aircraft designed to study active control of flexible structures. The vehicle is easily reconfigured to allow for testing of different configurations. The vehicle is being used to study new sensor, actuator, modeling and controls technologies. These new technologies will allow for lighter vehicles and new configurations that exceed the efficiency currently achievable. A description of the vehicle and the current research efforts that it enables are presented.
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Nonparametric method for failures diagnosis in the actuating subsystem of aircraft control system
Terentev, M. N.; Karpenko, S. S.; Zybin, E. Yu; Kosyanchuk, V. V.
2018-02-01
In this paper we design a nonparametric method for failures diagnosis in the aircraft control system that uses the measurements of the control signals and the aircraft states only. It doesn’t require a priori information of the aircraft model parameters, training or statistical calculations, and is based on analytical nonparametric one-step-ahead state prediction approach. This makes it possible to predict the behavior of unidentified and failure dynamic systems, to weaken the requirements to control signals, and to reduce the diagnostic time and problem complexity.
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Boughari, Yamina
New methodologies have been developed to optimize the integration, testing and certification of flight control systems, an expensive process in the aerospace industry. This thesis investigates the stability of the Cessna Citation X aircraft without control, and then optimizes two different flight controllers from design to validation. The aircraft's model was obtained from the data provided by the Research Aircraft Flight Simulator (RAFS) of the Cessna Citation business aircraft. To increase the stability and control of aircraft systems, optimizations of two different flight control designs were performed: 1) the Linear Quadratic Regulation and the Proportional Integral controllers were optimized using the Differential Evolution algorithm and the level 1 handling qualities as the objective function. The results were validated for the linear and nonlinear aircraft models, and some of the clearance criteria were investigated; and 2) the Hinfinity control method was applied on the stability and control augmentation systems. To minimize the time required for flight control design and its validation, an optimization of the controllers design was performed using the Differential Evolution (DE), and the Genetic algorithms (GA). The DE algorithm proved to be more efficient than the GA. New tools for visualization of the linear validation process were also developed to reduce the time required for the flight controller assessment. Matlab software was used to validate the different optimization algorithms' results. Research platforms of the aircraft's linear and nonlinear models were developed, and compared with the results of flight tests performed on the Research Aircraft Flight Simulator. Some of the clearance criteria of the optimized H-infinity flight controller were evaluated, including its linear stability, eigenvalues, and handling qualities criteria. Nonlinear simulations of the maneuvers criteria were also investigated during this research to assess the Cessna
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Emergency Flight Control of a Twin-Jet Commercial Aircraft using Manual Throttle Manipulation
Cole, Jennifer H.; Cogan, Bruce R.; Fullerton, C. Gordon; Burken, John J.; Venti, Michael W.; Burcham, Frank W.
2007-01-01
The Department of Homeland Security (DHS) created the PCAR (Propulsion-Controlled Aircraft Recovery) project in 2005 to mitigate the ManPADS (man-portable air defense systems) threat to the commercial aircraft fleet with near-term, low-cost proven technology. Such an attack could potentially cause a major FCS (flight control system) malfunction or other critical system failure onboard the aircraft, despite the extreme reliability of current systems. For the situations in which nominal flight controls are lost or degraded, engine thrust may be the only remaining means for emergency flight control [ref 1]. A computer-controlled thrust system, known as propulsion-controlled aircraft (PCA), was developed in the mid 1990s with NASA, McDonnell Douglas and Honeywell. PCA's major accomplishment was a demonstration of an automatic landing capability using only engine thrust [ref 11. Despite these promising results, no production aircraft have been equipped with a PCA system, due primarily to the modifications required for implementation. A minimally invasive option is TOC (throttles-only control), which uses the same control principles as PCA, but requires absolutely no hardware, software or other aircraft modifications. TOC is pure piloting technique, and has historically been utilized several times by flight crews, both military and civilian, in emergency situations stemming from a loss of conventional control. Since the 1990s, engineers at NASA Dryden Flight Research Center (DFRC) have studied TOC, in both simulation and flight, for emergency flight control with test pilots in numerous configurations. In general, it was shown that TOC was effective on certain aircraft for making a survivable landing. DHS sponsored both NASA Dryden Flight Research Center (Edwards, CA) and United Airlines (Denver, Colorado) to conduct a flight and simulation study of the TOC characteristics of a twin-jet commercial transport, and assess the ability of a crew to control an aircraft down to
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Neural network application to aircraft control system design
Troudet, Terry; Garg, Sanjay; Merrill, Walter C.
1991-01-01
The feasibility of using artificial neural network as control systems for modern, complex aerospace vehicles is investigated via an example aircraft control design study. The problem considered is that of designing a controller for an integrated airframe/propulsion longitudinal dynamics model of a modern fighter aircraft to provide independent control of pitch rate and airspeed responses to pilot command inputs. An explicit model following controller using H infinity control design techniques is first designed to gain insight into the control problem as well as to provide a baseline for evaluation of the neurocontroller. Using the model of the desired dynamics as a command generator, a multilayer feedforward neural network is trained to control the vehicle model within the physical limitations of the actuator dynamics. This is achieved by minimizing an objective function which is a weighted sum of tracking errors and control input commands and rates. To gain insight in the neurocontrol, linearized representations of the nonlinear neurocontroller are analyzed along a commanded trajectory. Linear robustness analysis tools are then applied to the linearized neurocontroller models and to the baseline H infinity based controller. Future areas of research identified to enhance the practical applicability of neural networks to flight control design.
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Neural network application to aircraft control system design
Troudet, Terry; Garg, Sanjay; Merrill, Walter C.
1991-01-01
The feasibility of using artificial neural networks as control systems for modern, complex aerospace vehicles is investigated via an example aircraft control design study. The problem considered is that of designing a controller for an integrated airframe/propulsion longitudinal dynamics model of a modern fighter aircraft to provide independent control of pitch rate and airspeed responses to pilot command inputs. An explicit model following controller using H infinity control design techniques is first designed to gain insight into the control problem as well as to provide a baseline for evaluation of the neurocontroller. Using the model of the desired dynamics as a command generator, a multilayer feedforward neural network is trained to control the vehicle model within the physical limitations of the actuator dynamics. This is achieved by minimizing an objective function which is a weighted sum of tracking errors and control input commands and rates. To gain insight in the neurocontrol, linearized representations of the nonlinear neurocontroller are analyzed along a commanded trajectory. Linear robustness analysis tools are then applied to the linearized neurocontroller models and to the baseline H infinity based controller. Future areas of research are identified to enhance the practical applicability of neural networks to flight control design.
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Chen, Xiaoliang; Zhao, Bin; Ma, Shoujiang; Chen, Cen; Hu, Daoyun; Zhou, Wenshuang; Zhu, Zuqing
2015-03-23
In this paper, we study how to improve the control plane resiliency of software-defined elastic optical networks (SD-EONs) and design a master-slave OpenFlow (OF) controller arrangement. Specifically, we introduce two OF controllers (OF-Cs), i.e., the master and slave OF-Cs, and make them work in a collaborative way to protect the SD-EON against controller failures. We develop a controller communication protocol (CCP) to facilitate the cooperation of the two OF-Cs. With the CCP, the master OF-C (M-OF-C) can synchronize network status to the slave OF-C (S-OF-C) in real time, while S-OF-C can quickly detect the failure of M-OF-C and take over the network control and management (NC&M) tasks timely to avoid service disruption. We implement the proposed framework in an SD-EON control plane testbed built with high-performance servers, and perform NC&M experiments with different network failure scenarios to demonstrate its effectiveness. Experimental results indicate that the proposed system can restore services in both the data and control planes of SD-EON jointly while maintaining relatively good scalability. To the best of our knowledge, this is the first demonstration that realizes control plane resiliency in SD-EONs.
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NASA Iced Aerodynamics and Controls Current Research
Addy, Gene
2009-01-01
This slide presentation reviews the state of current research in the area of aerodynamics and aircraft control with ice conditions by the Aviation Safety Program, part of the Integrated Resilient Aircraft Controls Project (IRAC). Included in the presentation is a overview of the modeling efforts. The objective of the modeling is to develop experimental and computational methods to model and predict aircraft response during adverse flight conditions, including icing. The Aircraft icing modeling efforts includes the Ice-Contaminated Aerodynamics Modeling, which examines the effects of ice contamination on aircraft aerodynamics, and CFD modeling of ice-contaminated aircraft aerodynamics, and Advanced Ice Accretion Process Modeling which examines the physics of ice accretion, and works on computational modeling of ice accretions. The IRAC testbed, a Generic Transport Model (GTM) and its use in the investigation of the effects of icing on its aerodynamics is also reviewed. This has led to a more thorough understanding and models, both theoretical and empirical of icing physics and ice accretion for airframes, advanced 3D ice accretion prediction codes, CFD methods for iced aerodynamics and better understanding of aircraft iced aerodynamics and its effects on control surface effectiveness.
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Direct Adaptive Aircraft Control Using Dynamic Cell Structure Neural Networks
Jorgensen, Charles C.
1997-01-01
A Dynamic Cell Structure (DCS) Neural Network was developed which learns topology representing networks (TRNS) of F-15 aircraft aerodynamic stability and control derivatives. The network is integrated into a direct adaptive tracking controller. The combination produces a robust adaptive architecture capable of handling multiple accident and off- nominal flight scenarios. This paper describes the DCS network and modifications to the parameter estimation procedure. The work represents one step towards an integrated real-time reconfiguration control architecture for rapid prototyping of new aircraft designs. Performance was evaluated using three off-line benchmarks and on-line nonlinear Virtual Reality simulation. Flight control was evaluated under scenarios including differential stabilator lock, soft sensor failure, control and stability derivative variations, and air turbulence.
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[Self-esteem, resilience, locus of control and suicide risk in nursing students].
Montes-Hidalgo, Javier; Tomás-Sábado, Joaquín
2016-01-01
Assuming that suicide is the result of a series of factors acting cumulatively, the aim of this paper was to study the association of self-esteem, resilience and locus of control with the risk of suicidal behavior in a sample of nursing students. Observational, cross-sectional and correlational study with 186 nursing students who answered a questionnaire that contained, in addition to demographic data, the Spanish forms of Rosenberg self-esteem scale, the brief resilient coping scale, the Plutchik scale of suicide risk and the Rotter's internal-external locus of control scale. The scores of males and females are very similar on all scales except Locus of Control, where a significantly greater tendency of females attributed to external control. 6.4% of students have scores indicating suicide risk. Suicide risk scores correlated negatively and significantly with self-esteem and resilience and positively with locus of control. The multiple linear regression analysis identified self-esteem as the main variable related to suicide risk. The results suggest that students who have low self-esteem, have difficulty in adjusting to adverse situations and tend to the external attribution of the consequences of their actions may have an increased risk of suicidal behavior. Furthermore, the identification of self-esteem as the important factor involved in suicide risk can help in designing prevention programs. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.
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Enhancing the stabilization of aircraft pitch motion control via intelligent and classical method
Lukman, H.; Munawwarah, S.; Azizan, A.; Yakub, F.; Zaki, S. A.; Rasid, Z. A.
2017-12-01
The pitching movement of an aircraft is very important to ensure passengers are intrinsically safe and the aircraft achieve its maximum stability. The equations governing the motion of an aircraft are a complex set of six nonlinear coupled differential equations. Under certain assumptions, it can be decoupled and linearized into longitudinal and lateral equations. Pitch control is a longitudinal problem and thus, only the longitudinal dynamics equations are involved in this system. It is a third order nonlinear system, which is linearized about the operating point. The system is also inherently unstable due to the presence of a free integrator. Because of this, a feedback controller is added in order to solve this problem and enhance the system performance. This study uses two approaches in designing controller: a conventional controller and an intelligent controller. The pitch control scheme consists of proportional, integral and derivatives (PID) for conventional controller and fuzzy logic control (FLC) for intelligent controller. Throughout the paper, the performance of the presented controllers are investigated and compared based on the common criteria of step response. Simulation results have been obtained and analysed by using Matlab and Simulink software. The study shows that FLC controller has higher ability to control and stabilize the aircraft's pitch angle as compared to PID controller.
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Karpenko, S. S.; Zybin, E. Yu; Kosyanchuk, V. V.
2018-02-01
In this paper we design a nonparametric method for failures detection and localization in the aircraft control system that uses the measurements of the control signals and the aircraft states only. It doesn’t require a priori information of the aircraft model parameters, training or statistical calculations, and is based on algebraic solvability conditions for the aircraft model identification problem. This makes it possible to significantly increase the efficiency of detection and localization problem solution by completely eliminating errors, associated with aircraft model uncertainties.
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Active fault-tolerant control strategy of large civil aircraft under elevator failures
Directory of Open Access Journals (Sweden)
Wang Xingjian
2015-12-01
Full Text Available Aircraft longitudinal control is the most important actuation system and its failures would lead to catastrophic accident of aircraft. This paper proposes an active fault-tolerant control (AFTC strategy for civil aircraft with different numbers of faulty elevators. In order to improve the fault-tolerant flight control system performance and effective utilization of the control surface, trimmable horizontal stabilizer (THS is considered to generate the extra pitch moment. A suitable switching mechanism with performance improvement coefficient is proposed to determine when it is worthwhile to utilize THS. Furthermore, AFTC strategy is detailed by using model following technique and the proposed THS switching mechanism. The basic fault-tolerant controller is designed to guarantee longitudinal control system stability and acceptable performance degradation under partial elevators failure. The proposed AFTC is applied to Boeing 747-200 numerical model and simulation results validate the effectiveness of the proposed AFTC approach.
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Analysis of Control Strategies for Aircraft Flight Upset Recovery
Crespo, Luis G.; Kenny, Sean P.; Cox, David E.; Muri, Daniel G.
2012-01-01
This paper proposes a framework for studying the ability of a control strategy, consisting of a control law and a command law, to recover an aircraft from ight conditions that may extend beyond the normal ight envelope. This study was carried out (i) by evaluating time responses of particular ight upsets, (ii) by evaluating local stability over an equilibrium manifold that included stall, and (iii) by bounding the set in the state space from where the vehicle can be safely own to wings-level ight. These states comprise what will be called the safely recoverable ight envelope (SRFE), which is a set containing the aircraft states from where a control strategy can safely stabilize the aircraft. By safe recovery it is implied that the tran- sient response stays between prescribed limits before converging to a steady horizontal ight. The calculation of the SRFE bounds yields the worst-case initial state corresponding to each control strategy. This information is used to compare alternative recovery strategies, determine their strengths and limitations, and identify the most e ective strategy. In regard to the control law, the authors developed feedback feedforward laws based on the gain scheduling of multivariable controllers. In regard to the command law, which is the mechanism governing the exogenous signals driving the feed- forward component of the controller, we developed laws with a feedback structure that combines local stability and transient response considera- tions. The upset recovery of the Generic Transport Model, a sub-scale twin-engine jet vehicle developed by NASA Langley Research Center, is used as a case study.
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EISENBERG, NANCY; CHANG, LEI; MA, YUE; HUANG, XIAORUI
2009-01-01
The purpose of the study was to examine the relations of authoritative parenting and corporal punishment to Chinese first and second graders’ effortful control (EC), impulsivity, ego resilience, and maladjustment, as well as mediating relations. A parent and teacher reported on children’s EC, impulsivity, and ego resilience; parents reported on children’s internalizing symptoms and their own parenting, and teachers and peers reported on children’s externalizing symptoms. Authoritative parenting and low corporal punishment predicted high EC, and EC mediated the relation between parenting and externalizing problems. In addition, impulsivity mediated the relation of corporal punishment to externalizing problems. The relation of parenting to children’s ego resilience was mediated by EC and/or impulsivity, and ego resilience mediated the relations of EC and impulsivity to internalizing problems. PMID:19338693
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Yuan, Yuan; Sun, Fuchun; Liu, Huaping
2016-07-01
This paper is concerned with the resilient control under denial-of-service attack launched by the intelligent attacker. The resilient control system is modelled as a multi-stage hierarchical game with a corresponding hierarchy of decisions made at cyber and physical layer, respectively. Specifically, the interaction in the cyber layer between different security agents is modelled as a static infinite Stackelberg game, while in the underlying physical layer the full-information H∞ minimax control with package drops is modelled as a different Stackelberg game. Both games are solved sequentially, which is consistent with the actual situations. Finally, the proposed method is applied to the load frequency control of the power system, which demonstrates its effectiveness.
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Smith, G. A.; Meyer, G.
1980-01-01
The results of a simulation study of an alternative design concept for an automatic landing control system are presented. The alternative design concept for an automatic landing control system is described. The design concept is the total aircraft flight control system (TAFCOS). TAFCOS is an open loop, feed forward system that commands the proper instantaneous thrust, angle of attack, and roll angle to achieve the forces required to follow the desired trajector. These dynamic trim conditions are determined by an inversion of the aircraft nonlinear force characteristics. The concept was applied to an A-7E aircraft approaching an aircraft carrier. The implementation details with an airborne digital computer are discussed. The automatic carrier landing situation is described. The simulation results are presented for a carrier approach with atmospheric disturbances, an approach with no disturbances, and for tailwind and headwind gusts.
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Human factors implications of unmanned aircraft accidents : flight-control problems
2006-04-01
This research focuses on three types of flight control problems associated with unmanned aircraft systems. The : three flight control problems are: 1) external pilot difficulties with inconsistent mapping of the controls to the : movement of the airc...
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Sliding Mode Fault Tolerant Control with Adaptive Diagnosis for Aircraft Engines
Xiao, Lingfei; Du, Yanbin; Hu, Jixiang; Jiang, Bin
2018-03-01
In this paper, a novel sliding mode fault tolerant control method is presented for aircraft engine systems with uncertainties and disturbances on the basis of adaptive diagnostic observer. By taking both sensors faults and actuators faults into account, the general model of aircraft engine control systems which is subjected to uncertainties and disturbances, is considered. Then, the corresponding augmented dynamic model is established in order to facilitate the fault diagnosis and fault tolerant controller design. Next, a suitable detection observer is designed to detect the faults effectively. Through creating an adaptive diagnostic observer and based on sliding mode strategy, the sliding mode fault tolerant controller is constructed. Robust stabilization is discussed and the closed-loop system can be stabilized robustly. It is also proven that the adaptive diagnostic observer output errors and the estimations of faults converge to a set exponentially, and the converge rate greater than some value which can be adjusted by choosing designable parameters properly. The simulation on a twin-shaft aircraft engine verifies the applicability of the proposed fault tolerant control method.
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Feedback Linearized Aircraft Control Using Dynamic Cell Structure
Jorgensen, C. C.
1998-01-01
A Dynamic Cell Structure (DCS ) Neural Network was developed which learns a topology representing network (TRN) of F-15 aircraft aerodynamic stability and control derivatives. The network is combined with a feedback linearized tracking controller to produce a robust control architecture capable of handling multiple accident and off-nominal flight scenarios. This paper describes network and its performance for accident scenarios including differential stabilator lock, soft sensor failure, control, stability derivative variation, and turbulence.
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PeerShield: determining control and resilience criticality of collaborative cyber assets in networks
Cam, Hasan
2012-06-01
As attackers get more coordinated and advanced in cyber attacks, cyber assets are required to have much more resilience, control effectiveness, and collaboration in networks. Such a requirement makes it essential to take a comprehensive and objective approach for measuring the individual and relative performances of cyber security assets in network nodes. To this end, this paper presents four techniques as to how the relative importance of cyber assets can be measured more comprehensively and objectively by considering together the main variables of risk assessment (e.g., threats, vulnerabilities), multiple attributes (e.g., resilience, control, and influence), network connectivity and controllability among collaborative cyber assets in networks. In the first technique, a Bayesian network is used to include the random variables for control, recovery, and resilience attributes of nodes, in addition to the random variables of threats, vulnerabilities, and risk. The second technique shows how graph matching and coloring can be utilized to form collaborative pairs of nodes to shield together against threats and vulnerabilities. The third technique ranks the security assets of nodes by incorporating multiple weights and thresholds of attributes into a decision-making algorithm. In the fourth technique, the hierarchically well-separated tree is enhanced to first identify critical nodes of a network with respect to their attributes and network connectivity, and then selecting some nodes as driver nodes for network controllability.
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Directory of Open Access Journals (Sweden)
Qinghua Zeng
2015-07-01
Full Text Available This article proposes a linear matrix inequality–based robust controller design approach to implement the synchronous design of aircraft control discipline and other disciplines, in which the variation in design parameters is treated as equivalent perturbations. Considering the complicated mapping relationships between the coefficient arrays of aircraft motion model and the aircraft design parameters, the robust controller designed is directly based on the variation in these coefficient arrays so conservative that the multidisciplinary design optimization problem would be too difficult to solve, or even if there is a solution, the robustness of design result is generally poor. Therefore, this article derives the uncertainty model of disciplinary design parameters based on response surface approximation, converts the design problem of the robust controller into a problem of solving a standard linear matrix inequality, and theoretically gives a less conservative design method of the robust controller which is based on the variation in design parameters. Furthermore, the concurrent subspace approach is applied to the multidisciplinary system with this kind of robust controller in the design loop. A multidisciplinary design optimization of a tailless aircraft as example is shown that control discipline can be synchronous optimal design with other discipline, especially this method will greatly reduce the calculated amount of multidisciplinary design optimization and make multidisciplinary design optimization results more robustness of flight performance.
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Configuration management and automatic control of an augmentor wing aircraft with vectored thrust
Cicolani, L. S.; Sridhar, B.; Meyer, G.
1979-01-01
An advanced structure for automatic flight control logic for powered-lift aircraft operating in terminal areas is under investigation at Ames Research Center. This structure is based on acceleration control; acceleration commands are constructed as the sum of acceleration on the reference trajectory and a corrective feedback acceleration to regulate path tracking errors. The central element of the structure, termed a Trimmap, uses a model of the aircraft aerodynamic and engine forces to calculate the control settings required to generate the acceleration commands. This report describes the design criteria for the Trimmap and derives a Trimmap for Ames experimental augmentor wing jet STOL research aircraft.
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Air Traffic Controller Acceptability of Unmanned Aircraft System Detect-and-Avoid Thresholds
Mueller, Eric R.; Isaacson, Douglas R.; Stevens, Derek
2016-01-01
A human-in-the-loop experiment was conducted with 15 retired air traffic controllers to investigate two research questions: (a) what procedures are appropriate for the use of unmanned aircraft system (UAS) detect-and-avoid systems, and (b) how long in advance of a predicted close encounter should pilots request or execute a separation maneuver. The controller participants managed a busy Oakland air route traffic control sector with mixed commercial/general aviation and manned/UAS traffic, providing separation services, miles-in-trail restrictions and issuing traffic advisories. Controllers filled out post-scenario and post-simulation questionnaires, and metrics were collected on the acceptability of procedural options and temporal thresholds. The states of aircraft were also recorded when controllers issued traffic advisories. Subjective feedback indicated a strong preference for pilots to request maneuvers to remain well clear from intruder aircraft rather than deviate from their IFR clearance. Controllers also reported that maneuvering at 120 seconds until closest point of approach (CPA) was too early; maneuvers executed with less than 90 seconds until CPA were more acceptable. The magnitudes of the requested maneuvers were frequently judged to be too large, indicating a possible discrepancy between the quantitative UAS well clear standard and the one employed subjectively by manned pilots. The ranges between pairs of aircraft and the times to CPA at which traffic advisories were issued were used to construct empirical probability distributions of those metrics. Given these distributions, we propose that UAS pilots wait until an intruder aircraft is approximately 80 seconds to CPA or 6 nmi away before requesting a maneuver, and maneuver immediately if the intruder is within 60 seconds and 4 nmi. These thresholds should make the use of UAS detect and avoid systems compatible with current airspace procedures and controller expectations.
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Integrated Flight and Propulsion Controls for Advanced Aircraft Configurations
Merrill, Walter; Garg, Sanjay
1995-01-01
The research vision of the NASA Lewis Research Center in the area of integrated flight and propulsion controls technologies is described. In particular the Integrated Method for Propulsion and Airframe Controls developed at the Lewis Research Center is described including its application to an advanced aircraft configuration. Additionally, future research directions in integrated controls are described.
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Manual Throttles-Only Control Effectivity for Emergency Flight Control of Transport Aircraft
Stevens, Richard; Burcham, Frank W., Jr.
2009-01-01
If normal aircraft flight controls are lost, emergency flight control may be attempted using only the thrust of engines. Collective thrust is used to control flightpath, and differential thrust is used to control bank angle. One issue is whether a total loss of hydraulics (TLOH) leaves an airplane in a recoverable condition. Recoverability is a function of airspeed, altitude, flight phase, and configuration. If the airplane can be recovered, flight test and simulation results on several transport-class airplanes have shown that throttles-only control (TOC) is usually adequate to maintain up-and-away flight, but executing a safe landing is very difficult. There are favorable aircraft configurations, and also techniques that will improve recoverability and control and increase the chances of a survivable landing. The DHS and NASA have recently conducted a flight and simulator study to determine the effectivity of manual throttles-only control as a way to recover and safely land a range of transport airplanes. This paper discusses TLOH recoverability as a function of conditions, and TOC landability results for a range of transport airplanes, and some key techniques for flying with throttles and making a survivable landing. Airplanes evaluated include the B-747, B-767, B-777, B-757, A320, and B-737 airplanes.
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EISENBERG, NANCY; CHANG, LEI; MA, YUE; HUANG, XIAORUI
2009-01-01
The purpose of the study was to examine the relations of authoritative parenting and corporal punishment to Chinese first and second graders’ effortful control (EC), impulsivity, ego resilience, and maladjustment, as well as mediating relations. A parent and teacher reported on children’s EC, impulsivity, and ego resilience; parents reported on children’s internalizing symptoms and their own parenting, and teachers and peers reported on children’s externalizing symptoms. Authoritative parenti...
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High Assurance Control of Cyber-Physical Systems with Application to Unmanned Aircraft Systems
Kwon, Cheolhyeon
With recent progress in the networked embedded control technology, cyber attacks have become one of the major threats to Cyber-Physical Systems (CPSs) due to their close integration of physical processes, computational resources, and communication capabilities. While CPSs have various applications in both military and civilian uses, their on-board automation and communication afford significant advantages over a system without such abilities, but these benefits come at the cost of possible vulnerability to cyber attacks. Traditionally, most cyber security studies in CPSs are mainly based on the computer security perspective, focusing on issues such as the trustworthiness of data flow, without rigorously considering the system's physical processes such as real-time dynamic behaviors. While computer security components are key elements in the hardware/software layer, these methods alone are not sufficient for diagnosing the healthiness of the CPSs' physical behavior. In seeking to address this problem, this research work proposes a control theoretic perspective approach which can accurately represent the interactions between the physical behavior and the logical behavior (computing resources) of the CPS. Then a controls domain aspect is explored extending beyond just the logical process of the CPS to include the underlying physical behavior. This approach will allow the CPS whose physical operations are robust/resilient to the damage caused by cyber attacks, successfully complementing the existing CPS security architecture. It is important to note that traditional fault-tolerant/robust control methods could not be directly applicable to achieve resiliency against malicious cyber attacks which can be designed sophisticatedly to spoof the security/safety monitoring system (note this is different from common faults). Thus, security issues at this layer require different risk management to detect cyber attacks and mitigate their impact within the context of a unified
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Maltby, John; Day, Liz; Hall, Sophie
2015-01-01
The current paper presents a new measure of trait resilience derived from three common mechanisms identified in ecological theory: Engineering, Ecological and Adaptive (EEA) resilience. Exploratory and confirmatory factor analyses of five existing resilience scales suggest that the three trait resilience facets emerge, and can be reduced to a 12-item scale. The conceptualization and value of EEA resilience within the wider trait and well-being psychology is illustrated in terms of differing relationships with adaptive expressions of the traits of the five-factor personality model and the contribution to well-being after controlling for personality and coping, or over time. The current findings suggest that EEA resilience is a useful and parsimonious model and measure of trait resilience that can readily be placed within wider trait psychology and that is found to contribute to individual well-being. PMID:26132197
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The Application of mu Analysis and Synthesis to the Control of an ASTOVL Aircraft
DEFF Research Database (Denmark)
Tøffner-Clausen, S.; Andersen, Palle; Breslin, S.G.
1995-01-01
A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point.......A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point....
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Directory of Open Access Journals (Sweden)
Wang Hongyu
2018-01-01
Full Text Available This paper presents the design of a symmetrical quad-rotor biplane tail-sitter VTOL UAV (Vertical Take-off and Landing Unmanned Aerial Vehicle which is composed of four rotors and two symmetrically mounted fixed wings. This aircraft achieves high accuracy in the attitude control and smooth flight mode transition with four rotors rather than the conventional VTOL UAVs using control surfaces. The proposal of angled rotor mounting is adopted to address the issue of insufficient yaw control authority. The layout of symmetrically mounted fixed wings makes the aircraft have capability of rapid bidirectional flight mode transition to improve maneuverability. To validate the performance of the aircraft, simulation and flight experiments are both implemented. These results show that the aircraft has a rapid yaw response under condition of the stable attitude control. In comparative experiment, it is shown that the aircraft is more flexible than other similar configuration of aircrafts. This symmetrical quad-rotor biplane tail-sitter VTOL UAV will have a wide range of potential applications in the military and civilian areas due to its superior performance..
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Individual and collective climate control in aircraft cabins
Jacobs, P.; Gids, W.F. de
2006-01-01
A new concept for aircraft cabin climatisation has been developed in which the seat is the main Indoor Air Quality (IAQ) and temperature control system for the passengers containing provisions for local supply and local exhaust of air. Direct supply of clean outside air in the breathing zone,
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Lantieri, Linda
2008-01-01
The capacity to be in control of one's thoughts, emotions, and physiology can form an internal safety net preparing children to face the challenges and opportunities of life. This is the goal of the Inner Resilience Program in the New York City Schools. Teachers in the Inner Resilience Program's intervention are exposed to calming and focusing…
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Combining control input with flight path data to evaluate pilot performance in transport aircraft.
Ebbatson, Matt; Harris, Don; Huddlestone, John; Sears, Rodney
2008-11-01
When deriving an objective assessment of piloting performance from flight data records, it is common to employ metrics which purely evaluate errors in flight path parameters. The adequacy of pilot performance is evaluated from the flight path of the aircraft. However, in large jet transport aircraft these measures may be insensitive and require supplementing with frequency-based measures of control input parameters. Flight path and control input data were collected from pilots undertaking a jet transport aircraft conversion course during a series of symmetric and asymmetric approaches in a flight simulator. The flight path data were analyzed for deviations around the optimum flight path while flying an instrument landing approach. Manipulation of the flight controls was subject to analysis using a series of power spectral density measures. The flight path metrics showed no significant differences in performance between the symmetric and asymmetric approaches. However, control input frequency domain measures revealed that the pilots employed highly different control strategies in the pitch and yaw axes. The results demonstrate that to evaluate pilot performance fully in large aircraft, it is necessary to employ performance metrics targeted at both the outer control loop (flight path) and the inner control loop (flight control) parameters in parallel, evaluating both the product and process of a pilot's performance.
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Terminal Control Area Aircraft Scheduling and Trajectory Optimization Approaches
Directory of Open Access Journals (Sweden)
Samà Marcella
2017-01-01
Full Text Available Aviation authorities are seeking optimization methods to better use the available infrastructure and better manage aircraft movements. This paper deals with the realtime scheduling of take-off and landing aircraft at a busy terminal control area and with the optimization of aircraft trajectories during the landing procedures. The first problem aims to reduce the propagation of delays, while the second problem aims to either minimize the travel time or reduce the fuel consumption. Both problems are particularly complex, since the first one is NP-hard while the second one is nonlinear and a combined solution needs to be computed in a short-time during operations. This paper proposes a framework for the lexicographic optimization of the two problems. Computational experiments are performed for the Milano Malpensa airport and show the existing gaps between the performance indicators of the two problems when different lexicographic optimization approaches are considered.
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Commercial Aircraft Trajectory Planning based on Multiphase Mixed-Integer Optimal Control
Soler Arnedo, Manuel Fernando
2017-01-01
The main goal of this dissertation is to develop optimal control techniques for aircraft trajectory planning looking at reduction of fuel consumption, emissions and overfly charges in flight plans. The calculation of a flight plan involves the consideration of multiple factors. They can be classified as either continuous or discrete, and include nonlinear aircraft performance, atmospheric conditions, wind conditions, airspace structure, amount of departure fuel, and operational...
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Jarrett, Thomas
2008-01-01
Warrior Resilience Training (WRT) is an educational class designed to enhance Warrior resilience, thriving, and posttraumatic growth for Soldiers deployed in Operation Iraqi Freedom. Warrior Resilience Training uses rational emotive behavior therapy (REBT), Army leadership principles, and positive psychology as a vehicle for students to apply resilient philosophies derived from Army Warrior Ethos, Stoic philosophy, and the survivor and resiliency literature. Students in WRT are trained to focus upon virtue, character, and emotional self-regulation by constructing and maintaining a personal resiliency philosophy that emphasizes critical thinking, rationality, virtue, and Warrior Ethos. The author, an Army licensed clinical social worker, executive coach, REBT doctoral fellow, and former Special Forces noncommissioned officer, describes his initial experience teaching WRT during Operation Iraqi Freedom to combat medics and Soldiers from 2005 to 2006, and his experience as a leader of a combat stress control prevention team currently in Iraq offering mobile WRT classes in-theater. Warrior Resilience Training rationale, curriculum, variants (like Warrior Family Resilience Training), and feedback are included, with suggestions as to how behavioral health providers and combat stress control teams might better integrate their services with leaders, chaplains, and commands to better market combat stress resiliency, reduce barriers to care, and promote force preservation. Informal analysis of class feedback from 1168 respondents regarding WRT reception and utilization is examined.
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Kreutzer, Jeffrey S; Marwitz, Jennifer H; Sima, Adam P; Mills, Ana; Hsu, Nancy H; Lukow, Herman R
2018-05-24
Examine a psychoeducational and skill-building intervention's effectiveness for individuals after traumatic brain injury (TBI), using a two-arm, parallel, randomized, controlled trial with wait-listed control. The Resilience and Adjustment Intervention (RAI) targets adjustment challenges and emphasizes education, skill-building and psychological support. Overall, 160 outpatients were randomly assigned to a treatment or wait-list control (WLC) group. The manualized treatment was delivered in seven 1-h sessions. The Connor-Davidson Resilience Scale (CD-RISC) was the primary outcome measure. Secondary measures included the Mayo Portland Adaptability Inventory-4 (MPAI-4), Brief Symptom Inventory-18 (BSI-18) and 13-Item Stress Test. After adjusting for injury severity, education and time postinjury, the RAI group (N = 75) demonstrated a significantly greater increase in resilience (effect size = 1.03) compared to the WLC group (N = 73). Participants in the RAI group demonstrated more favourable scores on the MPAI-4 Adjustment and Ability Indices, BSI-18 and the 13-item Stress Test. However, only the CD-RISC and BSI-18 demonstrated a clinically significant difference. In addition, RAI participants demonstrated maintenance of gains from pre-treatment to 3-month follow-up; however, only the BSI-18 maintained a clinically significant difference. Investigation provided evidence that a resilience-focused intervention can improve psychological health and adjustment after TBI. Additional research is needed to ascertain the longer term benefits of intervention and the efficacy of alternative delivery methods (e.g., via telephone, Internet).
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Yoeh, Seang Shen; Yang, Tao; Tarisciotti, Luca; Hill, Christopher Ian; Bozhko, Serhiy
2016-01-01
The current trend for future aircraft is the adoption of the More Electric Aircraft (MEA) concept. The electrical based starter-generator (S/G) system is one of the core ideas from the MEA concept. The PI based control scheme has been investigated in various papers for the permanent magnet based S/G system. Different control schemes are to be considered to improve the control performance of the S/G system. A type of non-linear control called Model Predictive Control (MPC) is considered for it...
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Burcham, Frank W., Jr.; Kaneshige, John; Bull, John; Maine, Trindel A.
1999-01-01
With the advent of digital engine control systems, considering the use of engine thrust for emergency flight control has become feasible. Many incidents have occurred in which engine thrust supplemented or replaced normal aircraft flight controls. In most of these cases, a crash has resulted, and more than 1100 lives have been lost. The NASA Dryden Flight Research Center has developed a propulsion-controlled aircraft (PCA) system in which computer-controlled engine thrust provides emergency flight control capability. Using this PCA system, an F-15 and an MD-11 airplane have been landed without using any flight controls. In simulations, C-17, B-757, and B-747 PCA systems have also been evaluated successfully. These tests used full-authority digital electronic control systems on the engines. Developing simpler PCA systems that can operate without full-authority engine control, thus allowing PCA technology to be installed on less capable airplanes or at lower cost, is also a desire. Studies have examined simplified ?PCA Ultralite? concepts in which thrust control is provided using an autothrottle system supplemented by manual differential throttle control. Some of these concepts have worked well. The PCA Ultralite study results are presented for simulation tests of MD-11, B-757, C-17, and B-747 aircraft.
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A Generic Inner-Loop Control Law Structure for Six-Degree-of-Freedom Conceptual Aircraft Design
Cox, Timothy H.; Cotting, M. Christopher
2005-01-01
A generic control system framework for both real-time and batch six-degree-of-freedom simulations is presented. This framework uses a simplified dynamic inversion technique to allow for stabilization and control of any type of aircraft at the pilot interface level. The simulation, designed primarily for the real-time simulation environment, also can be run in a batch mode through a simple guidance interface. Direct vehicle-state acceleration feedback is required with the simplified dynamic inversion technique. The estimation of surface effectiveness within real-time simulation timing constraints also is required. The generic framework provides easily modifiable control variables, allowing flexibility in the variables that the pilot commands. A direct control allocation scheme is used to command aircraft effectors. Primary uses for this system include conceptual and preliminary design of aircraft, when vehicle models are rapidly changing and knowledge of vehicle six-degree-of-freedom performance is required. A simulated airbreathing hypersonic vehicle and simulated high-performance fighter aircraft are used to demonstrate the flexibility and utility of the control system.
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Combustion Dynamics and Control for Ultra Low Emissions in Aircraft Gas-Turbine Engines
DeLaat, John C.
2011-01-01
Future aircraft engines must provide ultra-low emissions and high efficiency at low cost while maintaining the reliability and operability of present day engines. The demands for increased performance and decreased emissions have resulted in advanced combustor designs that are critically dependent on efficient fuel/air mixing and lean operation. However, all combustors, but most notably lean-burning low-emissions combustors, are susceptible to combustion instabilities. These instabilities are typically caused by the interaction of the fluctuating heat release of the combustion process with naturally occurring acoustic resonances. These interactions can produce large pressure oscillations within the combustor and can reduce component life and potentially lead to premature mechanical failures. Active Combustion Control which consists of feedback-based control of the fuel-air mixing process can provide an approach to achieving acceptable combustor dynamic behavior while minimizing emissions, and thus can provide flexibility during the combustor design process. The NASA Glenn Active Combustion Control Technology activity aims to demonstrate active control in a realistic environment relevant to aircraft engines by providing experiments tied to aircraft gas turbine combustors. The intent is to allow the technology maturity of active combustion control to advance to eventual demonstration in an engine environment. Work at NASA Glenn has shown that active combustion control, utilizing advanced algorithms working through high frequency fuel actuation, can effectively suppress instabilities in a combustor which emulates the instabilities found in an aircraft gas turbine engine. Current efforts are aimed at extending these active control technologies to advanced ultra-low-emissions combustors such as those employing multi-point lean direct injection.
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Active vibration control of a full scale aircraft wing using a reconfigurable controller
Prakash, Shashikala; Renjith Kumar, T. G.; Raja, S.; Dwarakanathan, D.; Subramani, H.; Karthikeyan, C.
2016-01-01
This work highlights the design of a Reconfigurable Active Vibration Control (AVC) System for aircraft structures using adaptive techniques. The AVC system with a multichannel capability is realized using Filtered-X Least Mean Square algorithm (FxLMS) on Xilinx Virtex-4 Field Programmable Gate Array (FPGA) platform in Very High Speed Integrated Circuits Hardware Description Language, (VHDL). The HDL design is made based on Finite State Machine (FSM) model with Floating point Intellectual Property (IP) cores for arithmetic operations. The use of FPGA facilitates to modify the system parameters even during runtime depending on the changes in user's requirements. The locations of the control actuators are optimized based on dynamic modal strain approach using genetic algorithm (GA). The developed system has been successfully deployed for the AVC testing of the full-scale wing of an all composite two seater transport aircraft. Several closed loop configurations like single channel and multi-channel control have been tested. The experimental results from the studies presented here are very encouraging. They demonstrate the usefulness of the system's reconfigurability for real time applications.
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Directory of Open Access Journals (Sweden)
Yamina BOUGHARI
2017-06-01
Full Text Available In this paper the Cessna Citation X clearance criteria were evaluated for a new Flight Controller. The Flight Control Law were optimized and designed for the Cessna Citation X flight envelope by combining the Deferential Evolution algorithm, the Linear Quadratic Regulator method, and the Proportional Integral controller during a previous research presented in part 1. The optimal controllers were used to reach satisfactory aircraft’s dynamic and safe flight operations with respect to the augmentation systems’ handling qualities, and design requirements. Furthermore the number of controllers used to control the aircraft in its flight envelope was optimized using the Linear Fractional Representations features. To validate the controller over the whole aircraft flight envelope, the linear stability, eigenvalue, and handling qualities criteria in addition of the nonlinear analysis criteria were investigated during this research to assess the business aircraft for flight control clearance and certification. The optimized gains provide a very good stability margins as the eigenvalue analysis shows that the aircraft has a high stability, and a very good flying qualities of the linear aircraft models are ensured in its entire flight envelope, its robustness is demonstrated with respect to uncertainties due to its mass and center of gravity variations.
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Investigation of Practical Flight Control Systems for Small Aircraft
Falkena, W.
2012-01-01
Personal air transportation utilizing small aircraft is a market that is expected to grow significantly in the near future. However, seventy times more accidents occur in this segment as compared with the commercial aviation sector. The majority of these accidents is related to handling and control
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Revell, J. D.; Balena, F. J.; Koval, L. R.
1980-01-01
The acoustical treatment mass penalties required to achieve an interior noise level of 80 dBA for high speed, fuel efficient propfan-powered aircraft are determined. The prediction method used is based on theory developed for the outer shell dynamics, and a modified approach for add-on noise control element performance. The present synthesis of these methods is supported by experimental data. Three different sized aircraft are studied, including a widebody, a narrowbody and a business sized aircraft. Noise control penalties are calculated for each aircraft for two kinds of noise control designs: add-on designs, where the outer wall structure cannot be changed, and advanced designs where the outer wall stiffness level and the materials usage can be altered. For the add-on designs, the mass penalties range from 1.7 to 2.4 percent of the takeoff gross weight (TOGW) of the various aircraft, similar to preliminary estimates. Results for advanced designs show significant reductions of the mass penalties. For the advanced aluminum designs the penalties are 1.5% of TOGW, and for an all composite aircraft the penalties range from 0.74 to 1.4% of TOGW.
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Bayesian Software Health Management for Aircraft Guidance, Navigation, and Control
Schumann, Johann; Mbaya, Timmy; Menghoel, Ole
2011-01-01
Modern aircraft, both piloted fly-by-wire commercial aircraft as well as UAVs, more and more depend on highly complex safety critical software systems with many sensors and computer-controlled actuators. Despite careful design and V&V of the software, severe incidents have happened due to malfunctioning software. In this paper, we discuss the use of Bayesian networks (BNs) to monitor the health of the on-board software and sensor system, and to perform advanced on-board diagnostic reasoning. We will focus on the approach to develop reliable and robust health models for the combined software and sensor systems.
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Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.
2006-01-01
The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.
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Modeling and control for a blended wing body aircraft a case study
Schirrer, Alexander
2015-01-01
This book demonstrates the potential of the blended wing body (BWB) concept for significant improvement in both fuel efficiency and noise reduction and addresses the considerable challenges raised for control engineers because of characteristics like open-loop instability, large flexible structure, and slow control surfaces. This text describes state-of-the-art and novel modeling and control design approaches for the BWB aircraft under consideration. The expert contributors demonstrate how exceptional robust control performance can be achieved despite such stringent design constraints as guaranteed handling qualities, reduced vibration, and the minimization of the aircraft’s structural loads during maneuvers and caused by turbulence. As a result, this innovative approach allows the building of even lighter aircraft structures, and thus results in considerable efficiency improvements per passenger kilometer. The treatment of this large, complex, parameter-dependent industrial control problem highlights relev...
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Rashid, Asif; Masood, Tariq; Erkoyuncu, John Ahmet; Tjahjono, Benny; Khan, Nawar; Shami, Muiz-ud-din
2018-02-01
The research aims to investigate business value critical success factors (CSFs) of enterprise systems (ES) through their life cycle in pursuit of resilient smart factory for emerging aircraft industry. This article provides an extensive literature analysis of past 22 years based on conscientious criteria of authors: (i) who have published strategic content relevant to CSFs, (ii) received more than 300 citations and (iii) concurrently published two or more papers relevant to ES CSFs. The most cited strategic CSFs were termed as classical CSFs. The 22 CSFs were identified, validated and synthesised for better understanding of success across life cycle by aircraft industry experts. The top 10 empirically verified CSFs have numerous differences with past generic classical CSFs. This article canvases real insights of two distinct views: process and variance approaches of the ES CSFs. The process approach, which is a neglected research area, facilitates the researchers for identification of ES life cycle process coupled with a view of resource deployment when it is needed the most. While the variance approach facilitates practitioners and researchers in finding out which resource (CSF) is relatively more important. The significant findings for ES life cycle can help the practitioners and researchers to make rational decisions throughout the ES life cycle.
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Hierarchical Discrete Event Supervisory Control of Aircraft Propulsion Systems
Yasar, Murat; Tolani, Devendra; Ray, Asok; Shah, Neerav; Litt, Jonathan S.
2004-01-01
This paper presents a hierarchical application of Discrete Event Supervisory (DES) control theory for intelligent decision and control of a twin-engine aircraft propulsion system. A dual layer hierarchical DES controller is designed to supervise and coordinate the operation of two engines of the propulsion system. The two engines are individually controlled to achieve enhanced performance and reliability, necessary for fulfilling the mission objectives. Each engine is operated under a continuously varying control system that maintains the specified performance and a local discrete-event supervisor for condition monitoring and life extending control. A global upper level DES controller is designed for load balancing and overall health management of the propulsion system.
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Lavretsky, Helen; Siddarth, Prabha; Irwin, Michael R
2010-02-01
This study examined the potential of an antidepressant drug, escitalopram, to improve depression, resilience to stress, and quality of life in family dementia caregivers in a randomized placebo-controlled double-blinded trial. Forty family caregivers (43-91 years of age, 25 children and 15 spouses; 26 women) who were taking care of their relatives with Alzheimer disease were randomized to receive either escitalopram 10 mg/day or placebo for 12 weeks. Severity of depression, resilience, burden, distress, quality of life, and severity of care-recipient's cognitive and behavioral disturbances were assessed at baseline and over the course of the study. The Hamilton Depression Rating Scale scores at baseline ranged between 10 and 28. The groups were stratified by the diagnosis of major and minor depression. Most outcomes favored escitalopram over placebo. The severity of depression improved, and the remission rate was greater with the drug compared with placebo. Measures of anxiety, resilience, burden, and distress improved on escitalopram compared with placebo. Among caregivers, this small randomized controlled trial found that escitalopram use resulted in improvement in depression, resilience, burden and distress, and quality of life. Our results need to be confirmed in a larger sample.
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Quelling Cabin Noise in Turboprop Aircraft via Active Control
Kincaid, Rex K.; Laba, Keith E.; Padula, Sharon L.
1997-01-01
Cabin noise in turboprop aircraft causes passenger discomfort, airframe fatigue, and employee scheduling constraints due to OSHA standards for exposure to high levels of noise. The noise levels in the cabins of turboprop aircraft are typically 10 to 30 decibels louder than commercial jet noise levels. However. unlike jet noise the turboprop noise spectrum is dominated by a few low frequency tones. Active structural acoustic control is a method in which the control inputs (used to reduce interior noise) are applied directly to a vibrating structural acoustic system. The control concept modeled in this work is the application of in-plane force inputs to piezoceramic patches bonded to the wall of a vibrating cylinder. The goal is to determine the force inputs and locations for the piezoceramic actuators so that: (1) the interior noise is effectively damped; (2) the level of vibration of the cylinder shell is not increased; and (3) the power requirements needed to drive the actuators are not excessive. Computational experiments for data taken from a computer generated model and from a laboratory test article at NASA Langley Research Center are provided.
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Trust Control of VTOL Aircraft Part Deux
Dugan, Daniel C.
2014-01-01
Thrust control of Vertical Takeoff and Landing (VTOL) aircraft has always been a debatable issue. In most cases, it comes down to the fundamental question of throttle versus collective. Some aircraft used throttle(s), with a fore and aft longitudinal motion, some had collectives, some have used Thrust Levers where the protocol is still "Up is Up and Down is Down," and some have incorporated both throttles and collectives when designers did not want to deal with the Human Factors issues. There have even been combinations of throttles that incorporated an arc that have been met with varying degrees of success. A previous review was made of nineteen designs without attempting to judge the merits of the controller. Included in this paper are twelve designs entered in competition for the 1961 Tri-Service VTOL transport. Entries were from a Bell/Lockheed tiltduct, a North American tiltwing, a Vanguard liftfan, and even a Sikorsky tiltwing. Additional designs were submitted from Boeing Wichita (direct lift), Ling-Temco-Vought with its XC-142 tiltwing, Boeing Vertol's tiltwing, Mcdonnell's compound and tiltwing, and the Douglas turboduct and turboprop designs. A private party submitted a re-design of the Breguet 941 as a VTOL transport. It is important to document these 53 year-old designs to preserve a part of this country's aviation heritage.
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Investigation of an automatic trim algorithm for restructurable aircraft control
Weiss, J.; Eterno, J.; Grunberg, D.; Looze, D.; Ostroff, A.
1986-01-01
This paper develops and solves an automatic trim problem for restructurable aircraft control. The trim solution is applied as a feed-forward control to reject measurable disturbances following control element failures. Disturbance rejection and command following performances are recovered through the automatic feedback control redesign procedure described by Looze et al. (1985). For this project the existence of a failure detection mechanism is assumed, and methods to cope with potential detection and identification inaccuracies are addressed.
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Recent advance in nonlinear aeroelastic analysis and control of the aircraft
Directory of Open Access Journals (Sweden)
Xiang Jinwu
2014-02-01
Full Text Available A review on the recent advance in nonlinear aeroelasticity of the aircraft is presented in this paper. The nonlinear aeroelastic problems are divided into three types based on different research objects, namely the two dimensional airfoil, the wing, and the full aircraft. Different nonlinearities encountered in aeroelastic systems are discussed firstly, where the emphases is placed on new nonlinear model to describe tested nonlinear relationship. Research techniques, especially new theoretical methods and aeroelastic flutter control methods are investigated in detail. The route to chaos and the cause of chaotic motion of two-dimensional aeroelastic system are summarized. Various structural modeling methods for the high-aspect-ratio wing with geometric nonlinearity are discussed. Accordingly, aerodynamic modeling approaches have been developed for the aeroelastic modeling of nonlinear high-aspect-ratio wings. Nonlinear aeroelasticity about high-altitude long-endurance (HALE and fight aircrafts are studied separately. Finally, conclusions and the challenges of the development in nonlinear aeroelasticity are concluded. Nonlinear aeroelastic problems of morphing wing, energy harvesting, and flapping aircrafts are proposed as new directions in the future.
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A smartphone application of alcohol resilience treatment for behavioral self-control training.
Yu, Fei; Albers, Jörg; Gao, Tian; Wang, Minghao; Bilberg, Arne; Stenager, Elsebeth
2012-01-01
High relapse rate is one of the most prominent problems in addiction treatment. Alcohol Resilience Treatment (ART), an alcohol addiction therapy, is based on Cue Exposure Treatment, which has shown promising results in preliminary studies. ART aims at optimizing the core area of relapse prevention, and intends to improve patients' capability to withstand craving of alcohol. This method emphasizes the interplay of resilience and resourcefulness. It contains 6 sessions with different topics according to the stage of treatment circuit, and each session consists of 6 steps. Due to the purity and structure of the treatment rationale, it is realistic, reasonable and manageable to transform the method into a smartphone application. An ART app in Android system and an accessory of bilateral tactile stimulation were developed and will be used in a study with behavioral self-control training. This paper presents the design and realization of the smartphone based ART application. The design of a pilot study, which is to examine the benefits of a smartphone application providing behavioral self-control training, is also reported in this paper.
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Resilience Thinking: Integrating Resilience, Adaptability and Transformability
Directory of Open Access Journals (Sweden)
Carl Folke
2010-12-01
Full Text Available Resilience thinking addresses the dynamics and development of complex social-ecological systems (SES. Three aspects are central: resilience, adaptability and transformability. These aspects interrelate across multiple scales. Resilience in this context is the capacity of a SES to continually change and adapt yet remain within critical thresholds. Adaptability is part of resilience. It represents the capacity to adjust responses to changing external drivers and internal processes and thereby allow for development along the current trajectory (stability domain. Transformability is the capacity to cross thresholds into new development trajectories. Transformational change at smaller scales enables resilience at larger scales. The capacity to transform at smaller scales draws on resilience from multiple scales, making use of crises as windows of opportunity for novelty and innovation, and recombining sources of experience and knowledge to navigate social-ecological transitions. Society must seriously consider ways to foster resilience of smaller more manageable SESs that contribute to Earth System resilience and to explore options for deliberate transformation of SESs that threaten Earth System resilience.
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Belcastro, Christine M.
2011-01-01
Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex, resulting from numerous causal and contributing factors acting alone or more often in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper summarizes recent analysis results in identifying worst-case combinations of loss-of-control accident precursors and their time sequences, a holistic approach to preventing loss-of-control accidents in the future, and key requirements for validating the associated technologies.
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Lyapunov-based control of limit cycle oscillations in uncertain aircraft systems
Bialy, Brendan
Store-induced limit cycle oscillations (LCO) affect several fighter aircraft and is expected to remain an issue for next generation fighters. LCO arises from the interaction of aerodynamic and structural forces, however the primary contributor to the phenomenon is still unclear. The practical concerns regarding this phenomenon include whether or not ordnance can be safely released and the ability of the aircrew to perform mission-related tasks while in an LCO condition. The focus of this dissertation is the development of control strategies to suppress LCO in aircraft systems. The first contribution of this work (Chapter 2) is the development of a controller consisting of a continuous Robust Integral of the Sign of the Error (RISE) feedback term with a neural network (NN) feedforward term to suppress LCO behavior in an uncertain airfoil system. The second contribution of this work (Chapter 3) is the extension of the development in Chapter 2 to include actuator saturation. Suppression of LCO behavior is achieved through the implementation of an auxiliary error system that features hyperbolic functions and a saturated RISE feedback control structure. Due to the lack of clarity regarding the driving mechanism behind LCO, common practice in literature and in Chapters 2 and 3 is to replicate the symptoms of LCO by including nonlinearities in the wing structure, typically a nonlinear torsional stiffness. To improve the accuracy of the system model a partial differential equation (PDE) model of a flexible wing is derived (see Appendix F) using Hamilton's principle. Chapters 4 and 5 are focused on developing boundary control strategies for regulating the bending and twisting deformations of the derived model. The contribution of Chapter 4 is the construction of a backstepping-based boundary control strategy for a linear PDE model of an aircraft wing. The backstepping-based strategy transforms the original system to a exponentially stable system. A Lyapunov-based stability
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Nonlinear Multivariate Spline-Based Control Allocation for High-Performance Aircraft
Tol, H.J.; De Visser, C.C.; Van Kampen, E.; Chu, Q.P.
2014-01-01
High performance flight control systems based on the nonlinear dynamic inversion (NDI) principle require highly accurate models of aircraft aerodynamics. In general, the accuracy of the internal model determines to what degree the system nonlinearities can be canceled; the more accurate the model, the better the cancellation, and with that, the higher the performance of the controller. In this paper a new control system is presented that combines NDI with multivariate simplex spline based con...
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Non-fragile switched H∞ control for morphing aircraft with asynchronous switching
Directory of Open Access Journals (Sweden)
Haoyu CHENG
2017-06-01
Full Text Available This paper deals with the problem of non-fragile linear parameter-varying (LPV H∞ control for morphing aircraft with asynchronous switching. The switched LPV model of morphing aircraft is established by Jacobian linearization approach according to the nonlinear model. The data missing is taken into account in the link from sensors to controllers and the link from controllers to actuators, which satisfies Bernoulli distribution. The non-fragile switched LPV controllers are constructed with consideration of the uncertainties of controllers and asynchronous switching phenomenon. The parameter-dependent Lyapunov functional method and mode-dependent average dwell time (MDADT method are combined to guarantee the stability and prescribed performance of the system. The sufficient conditions on the solvability of the problem are derived in the form of linear matrix inequalities (LMI. In order to achieve higher efficiency of the designing process, an algorithm is applied to divide the whole set into subsets automatically. Simulation results are provided to verify the effectiveness and superiority of the method in the paper.
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Flight testing a propulsion-controlled aircraft emergency flight control system on an F-15 airplane
Burcham, F. W., Jr.; Burken, John; Maine, Trindel A.
1994-01-01
Flight tests of a propulsion-controlled aircraft (PCA) system on an F-15 airplane have been conducted at the NASA Dryden Flight Research Center. The airplane was flown with all flight control surfaces locked both in the manual throttles-only mode and in an augmented system mode. In the latter mode, pilot thumbwheel commands and aircraft feedback parameters were used to position the throttles. Flight evaluation results showed that the PCA system can be used to land an airplane that has suffered a major flight control system failure safely. The PCA system was used to recover the F-15 airplane from a severe upset condition, descend, and land. Pilots from NASA, U.S. Air Force, U.S. Navy, and McDonnell Douglas Aerospace evaluated the PCA system and were favorably impressed with its capability. Manual throttles-only approaches were unsuccessful. This paper describes the PCA system operation and testing. It also presents flight test results and pilot comments.
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Systems and Methods for Collaboratively Controlling at Least One Aircraft
Estkowski, Regina I. (Inventor)
2016-01-01
An unmanned vehicle management system includes an unmanned aircraft system (UAS) control station controlling one or more unmanned vehicles (UV), a collaborative routing system, and a communication network connecting the UAS and the collaborative routing system. The collaborative routing system being configured to receive flight parameters from an operator of the UAS control station and, based on the received flight parameters, automatically present the UAS control station with flight plan options to enable the operator to operate the UV in a defined airspace.
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Nonlinear Multivariate Spline-Based Control Allocation for High-Performance Aircraft
Tol, H.J.; De Visser, C.C.; Van Kampen, E.; Chu, Q.P.
2014-01-01
High performance flight control systems based on the nonlinear dynamic inversion (NDI) principle require highly accurate models of aircraft aerodynamics. In general, the accuracy of the internal model determines to what degree the system nonlinearities can be canceled; the more accurate the model,
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Evaluating multicast resilience in carrier ethernet
DEFF Research Database (Denmark)
Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang
2010-01-01
This paper gives an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we show how multicast traffic, which is essential for IPTV can be protected. We detail the ackground for resilience mechanisms and their control and e present Carrier Ethernet...... resilience methods for linear nd ring networks. By simulation we show that the vailability of a multicast connection can be significantly increased by applying protection methods....
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Directory of Open Access Journals (Sweden)
Margot Hill Clarvis
2015-07-01
Full Text Available As the human and financial costs of natural disasters rise and state finances continue to deplete, increasing attention is being placed on the role of the private sector to support disaster and climate resilience. However, not only is there a recognised lack of private finance to fill this gap, but international institutional and financing bodies tend to prioritise specific reactive response over preparedness and general resilience building. This paper utilises the central tenets of resilience thinking that have emerged from scholarship on social-ecological system resilience as a lens through which to assess investing in disaster risk reduction (DRR for resilience. It draws on an established framework of resilience principles and examples of resilience investments to explore how resilience principles can actually inform decisions around DRR and resilience investing. It proposes some key lessons for diversifying sources of finance in order to, in turn, enhance “financial resilience”. In doing so, it suggests a series of questions to align investments with resilience building, and to better balance the achievement of the resilience principles with financial requirements such as financial diversification and replicability. It argues for a critical look to be taken at how resilience principles, which focus on longer-term systems perspectives, could complement the focus in DRR on critical and immediate stresses.
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Nguyen, Nhan; James Urnes, Sr.
2012-01-01
Lightweight aircraft design has received a considerable attention in recent years as a means for improving cruise efficiency. Reducing aircraft weight results in lower lift requirements which directly translate into lower drag, hence reduced engine thrust requirements during cruise. The use of lightweight materials such as advanced composite materials has been adopted by airframe manufacturers in current and future aircraft. Modern lightweight materials can provide less structural rigidity while maintaining load-carrying capacity. As structural flexibility increases, aeroelastic interactions with aerodynamic forces and moments become an increasingly important consideration in aircraft design and aerodynamic performance. Furthermore, aeroelastic interactions with flight dynamics can result in issues with vehicle stability and control. Abstract This paper describes a recent aeroelastic modeling effort for an elastically shaped aircraft concept (ESAC). The aircraft model is based on the rigid-body generic transport model (GTM) originally developed at NASA Langley Research Center. The ESAC distinguishes itself from the GTM in that it is equipped with highly flexible wing structures as a weight reduction design feature. More significantly, the wings are outfitted with a novel control effector concept called variable camber continuous trailing edge (VCCTE) flap system for active control of wing aeroelastic deflections to optimize the local angle of attack of wing sections for improved aerodynamic efficiency through cruise drag reduction and lift enhancement during take-off and landing. The VCCTE flap is a multi-functional and aerodynamically efficient device capable of achieving high lift-to-drag ratios. The flap system is comprised of three chordwise segments that form the variable camber feature of the flap and multiple spanwise segments that form a piecewise continuous trailing edge. By configuring the flap camber and trailing edge shape, drag reduction could be
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Automatic Flight Control System Design of Level Change Mode for a Large Aircraft
Directory of Open Access Journals (Sweden)
Huajun Gong
2013-02-01
Full Text Available The level change mode is an essential part of large civil aircraft automatic flight control systems. In cruise, with the decrease of the plane's weight caused by fuel consumption and the influence of bad weather, such as thunderstorms, the level change mode is required to solve this problem. This work establishes a nonlinear model of large aircraft, takes level changed from 9500m to 10100m as an example to design control laws for the level change mode in cruise. The classical engineering method is used to design longitudinal and lateral control laws synthetically. The flight qualities are considered in the design process. Simulation results indicate the control laws can meet design requirements and have a good anti-gust performance.
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Gern, Frank; Vicroy, Dan D.; Mulani, Sameer B.; Chhabra, Rupanshi; Kapania, Rakesh K.; Schetz, Joseph A.; Brown, Derrell; Princen, Norman H.
2014-01-01
Traditional methods of control allocation optimization have shown difficulties in exploiting the full potential of controlling large arrays of control devices on innovative air vehicles. Artificial neutral networks are inspired by biological nervous systems and neurocomputing has successfully been applied to a variety of complex optimization problems. This project investigates the potential of applying neurocomputing to the control allocation optimization problem of Hybrid Wing Body (HWB) aircraft concepts to minimize control power, hinge moments, and actuator forces, while keeping system weights within acceptable limits. The main objective of this project is to develop a proof-of-concept process suitable to demonstrate the potential of using neurocomputing for optimizing actuation power for aircraft featuring multiple independently actuated control surfaces. A Nastran aeroservoelastic finite element model is used to generate a learning database of hinge moment and actuation power characteristics for an array of flight conditions and control surface deflections. An artificial neural network incorporating a genetic algorithm then uses this training data to perform control allocation optimization for the investigated aircraft configuration. The phase I project showed that optimization results for the sum of required hinge moments are improved by more than 12% over the best Nastran solution by using the neural network optimization process.
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Denieul , Yann; Alazard , Daniel; Bordeneuve-Guibé , Joël; Toussaint , Clément; Taquin , Gilles
2015-01-01
International audience; In this paper the problem of integrated design and control for a civil blended wing-body aircraft is addressed. Indeed this configuration faces remarkable challenges relatedto handling qualities: namely the aircraft configuration in this study features a strong longitudinal instability for some specific flight points. Moreover it may lack control efficiency despite large and redundant movables. Stabilizing such a configuration may then lead to high control surfaces rat...
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Cellier , Loïc; Cafieri , Sonia; Messine , Frederic
2013-01-01
International audience; In this paper a numerical study is provided to solve the aircraft conflict avoidance problem through velocity regulation maneuvers. Starting from optimal controlbased model and approaches in which aircraft accelerations are the controls, and by applying the direct shooting technique, we propose to study two different largescale nonlinear optimization problems. In order to compare different possibilities of implementation, two environments (AMPL and MATLAB) and determin...
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Aircraft Control Using Engine Thrust: A History of Learning TOC Real-Time
Cole, Jennifer H.; Batteas, Frank; Fullerton, Gordon
2006-01-01
A history of learning the operation of Throttles Only Control (TOC) to control an aircraft in real time using engine thrust is shown. The topics include: 1) Past TOC Accidents/Incidents; 2) 1972: DC-10 American Airlines; 3) May 1974: USAF B-52H; 4) April 1975: USAF C-5A; 5) April 1975: USAF C-5A; 6) 1981: USAF B-52G; 7) August 1985: JAL 123 B-747; 8) JAL 123 Survivor Story; 9) JAL 123 Investigation Findings; 10) July 1989: UAL 232 DC-10; 11) UAL 232 DC-10; 12) Eastwind 517 B-737; 13) November 2003: DHL A-300; 14) Historically, TOC has saved lives; 15) Automated Throttles-Only Control; 16) PCA Project; 17) Propulsion-Controlled Aircraft; 18) MD-11 PCA System and Flight Test Envelope; 19) MD-11 Simulation, PCA ILS-Soupled Landing Dispersion; 20) Throttles-Only Pitch and Roll Control Power; 21) PCA in Commercial Fleet; 22) Fall 2005: PCAR Project; 23) PCAR Background - TOC; and 24) PCAR Background - TOC.
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Integration of Predictive Display and Aircraft Flight Control System
Directory of Open Access Journals (Sweden)
Efremov A.V.
2017-01-01
Full Text Available The synthesis of predictive display information and direct lift control system are considered for the path control tracking tasks (in particular landing task. The both solutions are based on pilot-vehicle system analysis and requirements to provide the highest accuracy and lowest pilot workload. The investigation was carried out for cases with and without time delay in aircraft dynamics. The efficiency of the both ways for the flying qualities improvement and their integration is tested by ground based simulation.
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Flight Research into Simple Adaptive Control on the NASA FAST Aircraft
Hanson, Curtis E.
2011-01-01
A series of simple adaptive controllers with varying levels of complexity were designed, implemented and flight tested on the NASA Full-Scale Advanced Systems Testbed (FAST) aircraft. Lessons learned from the development and flight testing are presented.
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Directory of Open Access Journals (Sweden)
Ruth Langridge
2006-12-01
Full Text Available Resilience is a vital attribute that characterizes a system's capacity to cope with stress. Researchers have examined the measurement of resilience in ecosystems and in social-ecological systems, and the comparative vulnerability of social groups. Our paper refocuses attention on the processes and relations that create social resilience. Our central proposition is that the creation of social resilience is linked to a community's ability to access critical resources. We explore this proposition through an analysis of how community resilience to the stress of water scarcity is influenced by historically contingent mechanisms to gain, control, and maintain access to water. Access is defined broadly as the ability of a community to actually benefit from a resource, and includes a wider range of relations than those derived from property rights alone. We provide a framework for assessing the construction of social resilience and use it to examine, first, the different processes and relations that enabled four communities in northern California to acquire access to water, and second, how access contributed to their differential levels of resilience to potential water scarcity. Legal water rights are extremely difficult to alter, and given the variety of mechanisms that can generate access, our study suggests that strengthening and diversifying a range of structural and relational mechanisms to access water can enhance a community's resilience to water scarcity.
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Directory of Open Access Journals (Sweden)
Chaoyang Dong
2016-01-01
Full Text Available This paper proposes a control allocation method for the tracking control problem of a class of morphing aircraft with special actuators which are different from the conventional actuation surfaces. This design of actuators can bring about some potential advantages to the flight vehicles; however, due to the integral constraints, the desired control cannot be performed accurately; therefore, it leads to undesirable tracking errors, so influencing the performance of the system. Because the system could be control allocated, based on the designed cost function that describes the tracking errors, the cuckoo search algorithm (CSA is introduced to search for the optimum solution within the calculated actuator execution commands that are equivalent to the desired commands. Several improvement measures are proposed for boosting the efficiency of the CSA and ensuring reasonable solutions. Simulation results show that the proposed control allocation method is necessary and effective, and the improvement measures are helpful in obtaining the optimum solution.
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Projection-Based Adaptive Backstepping Control of a Transport Aircraft for Heavyweight Airdrop
Directory of Open Access Journals (Sweden)
Ri Liu
2015-01-01
Full Text Available An autopilot inner loop that combines backstepping control with adaptive function approximation is developed for airdrop operations. The complex nonlinear uncertainty of the aircraft-cargo model is factorized into a known matrix and an uncertainty function, and a projection-based adaptive approach is proposed to estimate this function. Using projection in the adaptation law bounds the estimated function and guarantees the robustness of the controller against time-varying external disturbances and uncertainties. The convergence properties and robustness of the control method are proved via Lyapunov theory. Simulations are conducted under the condition that one transport aircraft performs a maximum load airdrop task at a height of 82 ft, using single row single platform mode. The results show good performance and robust operation of the controller, and the airdrop mission performance indexes are satisfied, even in the presence of ±15% uncertainty in the aerodynamic coefficients, ±0.01 rad/s pitch rate disturbance, and 20% actuators faults.
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Identifying resilient and non-resilient middle-adolescents in a ...
African Journals Online (AJOL)
The aim in this study was to develop a way of identifying resilient and non- resilient middle adolescents in a formerly black-only urban residential (township) school, in order to ultimately support the development of learners' resilience under stressful circumstances. A Resilience Scale was developed to screen for resilient ...
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Developing a workplace resilience instrument.
Mallak, Larry A; Yildiz, Mustafa
2016-05-27
Resilience benefits from the use of protective factors, as opposed to risk factors, which are associated with vulnerability. Considerable research and instrument development has been conducted in clinical settings for patients. The need existed for an instrument to be developed in a workplace setting to measure resilience of employees. This study developed and tested a resilience instrument for employees in the workplace. The research instrument was distributed to executives and nurses working in the United States in hospital settings. Five-hundred-forty completed and usable responses were obtained. The instrument contained an inventory of workplace resilience, a job stress questionnaire, and relevant demographics. The resilience items were written based on previous work by the lead author and inspired by Weick's [1] sense-making theory. A four-factor model yielded an instrument having psychometric properties showing good model fit. Twenty items were retained for the resulting Workplace Resilience Instrument (WRI). Parallel analysis was conducted with successive iterations of exploratory and confirmatory factor analyses. Respondents were classified based on their employment with either a rural or an urban hospital. Executives had significantly higher WRI scores than nurses, controlling for gender. WRI scores were positively and significantly correlated with years of experience and the Brief Job Stress Questionnaire. An instrument to measure individual resilience in the workplace (WRI) was developed. The WRI's four factors identify dimensions of workplace resilience for use in subsequent investigations: Active Problem-Solving, Team Efficacy, Confident Sense-Making, and Bricolage.
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Resilience Thinking: Integrating Resilience, Adaptability and Transformability
Folke, C.; Carpenter, S.R.; Walker, B.; Scheffer, M.; Chapin, T.; Rockstrom, J.
2010-01-01
Resilience thinking addresses the dynamics and development of complex social-ecological systems (SES). Three aspects are central: resilience, adaptability and transformability. These aspects interrelate across multiple scales. Resilience in this context is the capacity of a SES to continually change
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A Generic Guidance and Control Structure for Six-Degree-of-Freedom Conceptual Aircraft Design
Cotting, M. Christopher; Cox, Timothy H.
2005-01-01
A control system framework is presented for both real-time and batch six-degree-of-freedom simulation. This framework allows stabilization and control with multiple command options, from body rate control to waypoint guidance. Also, pilot commands can be used to operate the simulation in a pilot-in-the-loop environment. This control system framework is created by using direct vehicle state feedback with nonlinear dynamic inversion. A direct control allocation scheme is used to command aircraft effectors. Online B-matrix estimation is used in the control allocation algorithm for maximum algorithm flexibility. Primary uses for this framework include conceptual design and early preliminary design of aircraft, where vehicle models change rapidly and a knowledge of vehicle six-degree-of-freedom performance is required. A simulated airbreathing hypersonic vehicle and a simulated high performance fighter are controlled to demonstrate the flexibility and utility of the control system.
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Development of Cursor-on-Target Control for Semi-Autonomous Unmanned Aircraft Systems
National Research Council Canada - National Science Library
Crouse, Joshua D
2007-01-01
.... The goal of this research is to develop a preliminary Cursor-on-Target control system to enable the operator to guide the unmanned aircraft with minimal workload during high task phases of flight...
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Chmitorz, A; Kunzler, A; Helmreich, I; Tüscher, O; Kalisch, R; Kubiak, T; Wessa, M; Lieb, K
2018-02-01
Psychological resilience refers to the phenomenon that many people are able to adapt to the challenges of life and maintain mental health despite exposure to adversity. This has stimulated research on training programs to foster psychological resilience. We evaluated concepts, methods and designs of 43 randomized controlled trials published between 1979 and 2014 which assessed the efficacy of such training programs and propose standards for future intervention research based on recent developments in the field. We found that concepts, methods and designs in current resilience intervention studies are of limited use to properly assess efficacy of interventions to foster resilience. Major problems are the use of definitions of resilience as trait or a composite of resilience factors, the use of unsuited assessment instruments, and inappropriate study designs. To overcome these challenges, we propose 1) an outcome-oriented definition of resilience, 2) an outcome-oriented assessment of resilience as change in mental health in relation to stressor load, and 3) methodological standards for suitable study designs of future intervention studies. Our proposals may contribute to an improved quality of resilience intervention studies and may stimulate further progress in this growing research field. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Green, Steven M.; Denbraven, Wim; Williams, David H.
1993-01-01
The development and evaluation of the profile negotiation process (PNP), an interactive process between an aircraft and air traffic control (ATC) that integrates airborne and ground-based automation capabilities to determine conflict-free trajectories that are as close to an aircraft's preference as possible, are described. The PNP was evaluated in a real-time simulation experiment conducted jointly by NASA's Ames and Langley Research Centers. The Ames Center/TRACON Automation System (CTAS) was used to support the ATC environment, and the Langley Transport Systems Research Vehicle (TSRV) piloted cab was used to simulate a 4D Flight Management System (FMS) capable aircraft. Both systems were connected in real time by way of voice and data lines; digital datalink communications capability was developed and evaluated as a means of supporting the air/ground exchange of trajectory data. The controllers were able to consistently and effectively negotiate nominally conflict-free vertical profiles with the 4D-equipped aircraft. The actual profiles flown were substantially closer to the aircraft's preference than would have been possible without the PNP. However, there was a strong consensus among the pilots and controllers that the level of automation of the PNP should be increased to make the process more transparent. The experiment demonstrated the importance of an aircraft's ability to accurately execute a negotiated profile as well as the need for digital datalink to support advanced air/ground data communications. The concept of trajectory space is proposed as a comprehensive approach for coupling the processes of trajectory planning and tracking to allow maximum pilot discretion in meeting ATC constraints.
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Maltby, John; Day, Liz; Hall, Sophie S; Chivers, Sally
2017-10-01
Research suggests that trait resilience may be best understood within an ecological resilient systems theory, comprising engineering, ecological, and adaptive capacity resilience. However, there is no evidence as to how this theory translates to specific life domains. Data from two samples (the United States, n = 1,278; the United Kingdom, n = 211) facilitated five studies that introduce the Domain-Specific Resilient Systems Scales for assessing ecological resilient systems theory within work, health, marriage, friendships, and education. The Domain-Specific Resilient Systems Scales are found to predict unique variance in job satisfaction, lower job burnout, quality-of-life following illness, marriage commitment, and educational engagement, while controlling for factors including sex, age, personality, cognitive ability, and trait resilience. The findings also suggest a distinction between the three resilience dimensions in terms of the types of systems to which they contribute. Engineering resilience may contribute most to life domains where an established system needs to be maintained, for example, one's health. Ecological resilience may contribute most to life domains where the system needs sustainability in terms of present and future goal orientation, for example, one's work. Adaptive Capacity may contribute most to life domains where the system needs to be retained, preventing it from reaching a crisis state, for example, work burnout.
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Engineering of Fast and Robust Adaptive Control for Fixed-Wing Unmanned Aircraft
2017-06-01
evaluate the use of adaptive control on fixed-wing unmanned aircraft . The growing demand for unmanned systems will inherit the costs associated with...aerospace environment . 2.2 Classical Feedback vs Adaptive Control Control of a system can be categorized into two required elements; the requirement to...stabilize the system in the presence of: 1. disturbances that affect the controlled states and outputs (pitch rate perturbation caused by environmental
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Teche, Stefania Pigatto; Barros, Alcina Juliana Soares; Rosa, Regis Goulart; Guimarães, Luciano Pinto; Cordini, Kariny Larissa; Goi, Julia Domingues; Hauck, Simone; Freitas, Lucia Helena
2017-01-01
This study investigated the association between resilience and posttraumatic stress disorder (PTSD) among Brazilian victims of urban violence. It also compared defense mechanisms, parental bonding, and childhood trauma between those who developed PTSD and those who did not. This cross-sectional case-control study included 66 adult subjects exposed to recent urban violence in southern Brazil - 33 with PTSD and 33 healthy controls matched by sex and age - who were administered the Resilience Scale, Defense Style Questionnaire, Parental Bonding Instrument, and Childhood Trauma Questionnaire. The statistical tests used were the McNemar test for categorical variables, the Wilcoxon signed-rank test for continuous asymmetric variables, and the paired Student t-test for continuous symmetric variables. The PTSD group showed lower total Resilience Scale scores compared with controls (128.4±20.7 vs. 145.8±13.1, respectively; p = 0.01), along with a lower ability to solve situations and lower personal values that give meaning to life (p = 0.019). They also had lower rates of mature defense mechanisms (p violence.
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Morphological brain measures of cortico-limbic inhibition related to resilience.
Gupta, Arpana; Love, Aubrey; Kilpatrick, Lisa A; Labus, Jennifer S; Bhatt, Ravi; Chang, Lin; Tillisch, Kirsten; Naliboff, Bruce; Mayer, Emeran A
2017-09-01
Resilience is the ability to adequately adapt and respond to homeostatic perturbations. Although resilience has been associated with positive health outcomes, the neuro-biological basis of resilience is poorly understood. The aim of the study was to identify associations between regional brain morphology and trait resilience with a focus on resilience-related morphological differences in brain regions involved in cortico-limbic inhibition. The relationship between resilience and measures of affect were also investigated. Forty-eight healthy subjects completed structural MRI scans. Self-reported resilience was measured using the Connor and Davidson Resilience Scale. Segmentation and regional parcellation of images was performed to yield a total of 165 regions. Gray matter volume (GMV), cortical thickness, surface area, and mean curvature were calculated for each region. Regression models were used to identify associations between morphology of regions belonging to executive control and emotional arousal brain networks and trait resilience (total and subscales) while controlling for age, sex, and total GMV. Correlations were also conducted between resilience scores and affect scores. Significant associations were found between GM changes in hypothesized brain regions (subparietal sulcus, intraparietal sulcus, amygdala, anterior mid cingulate cortex, and subgenual cingulate cortex) and resilience scores. There were significant positive correlations between resilience and positive affect and negative correlations with negative affect. Resilience was associated with brain morphology of regions involved in cognitive and affective processes related to cortico-limbic inhibition. Brain signatures associated with resilience may be a biomarker of vulnerability to disease. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
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A systematic method of smooth switching LPV controllers design for a morphing aircraft
Directory of Open Access Journals (Sweden)
Jiang Weilai
2015-12-01
Full Text Available This paper is concerned with a systematic method of smooth switching linear parameter-varying (LPV controllers design for a morphing aircraft with a variable wing sweep angle. The morphing aircraft is modeled as an LPV system, whose scheduling parameter is the variation rate of the wing sweep angle. By dividing the scheduling parameter set into subsets with overlaps, output feedback controllers which consider smooth switching are designed and the controllers in overlapped subsets are interpolated from two adjacent subsets. A switching law without constraint on the average dwell time is obtained which makes the conclusion less conservative. Furthermore, a systematic algorithm is developed to improve the efficiency of the controllers design process. The parameter set is divided into the fewest subsets on the premise that the closed-loop system has a desired performance. Simulation results demonstrate the effectiveness of this approach.
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Resilience in patients with psychotic disorder.
Bozikas, V; Parlapani, E
2016-01-01
The recovery movement differentiated clinical, which is related to disorder's symptoms, from personal recovery, which is outlined by a subjectively defined wellness state, characterised by hope and self-management. Schizophrenia research has long focused on risk factors and symptoms. The recovery movement triggered a focus shift from psychopathology towards better adjustment and growth despite living with schizophrenia. The recovery movement flourished parallel with positive psychology, the scientific study of ordinary human strengths and virtues investigating human motives and potentials. Understanding of human strengths could contribute to prevention or lessening of psychiatric disorders' devastating consequences, since optimism, sense of personal control and many other positive processes promote psychological health. Lately, the concepts of positive psychology have been implemented in schizophrenia research. Positive self-appraisals moderated suicidal ideation, even when patients experienced high levels of hopelessness.1 Additionally, among other factors, better self-images, internal locus of control (i.e. the perception that events in one's life relate to one's actions) and emphasis on personal efforts predicted a more favourable outcome in functioning of unmedicated patients.2 The concept of "resilience" is closely related to positive psychology. The American Psychological Association defines resilience as ''the process of adapting well in the face of adversity, trauma, threats or significant sources of stress''. The concept of resilience includes rebound from adversity.3 Determinants of resilience include biological, psychological, social and cultural factors that interact in a complex manner. The major manifestations of personal resilience are social competence, problem solving, autonomy and sense of purpose.5 Personality strengths that relate to resilience include high self-esteem, extroversion and optimism. Internal assets and personal competencies
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Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.
1986-01-01
The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.
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Resilience thinking: integrating resilience, adaptability and transformability
Carl Folke; Stephen R. Carpenter; Brian Walker; Marten Scheffer; Terry Chapin; Johan. Rockstrom
2010-01-01
Resilience thinking addresses the dynamics and development of complex social-ecological systems (SES). Three aspects are central: resilience, adaptability and transformability. These aspects interrelate across multiple scales. Resilience in this context is the capacity of a SES to continually change and adapt yet remain within critical thresholds. Adaptability is part...
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Aircraft Interior Noise Control Using Distributed Piezoelectric Actuators
Sun, Jian Q.
1996-01-01
Developing a control system that can reduce the noise and structural vibration at the same time is an important task. This talk presents one possible technical approach for accomplishing this task. The target application of the research is for aircraft interior noise control. The emphasis of the present approach is not on control strategies, but rather on the design of actuators for the control system. In the talk, a theory of distributed piezoelectric actuators is introduced. A uniform cylindrical shell is taken as a simplified model of fuselage structures to illustrate the effectiveness of the design theory. The actuators developed are such that they can reduce the tonal structural vibration and interior noise in a wide range of frequencies. Extensive computer simulations have been done to study various aspects of the design theory. Experiments have also been conducted and the test results strongly support the theoretical development.
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From resilience thinking to Resilience Planning: Lessons from practice.
Sellberg, M M; Ryan, P; Borgström, S T; Norström, A V; Peterson, G D
2018-07-01
Resilience thinking has frequently been proposed as an alternative to conventional natural resource management, but there are few studies of its applications in real-world settings. To address this gap, we synthesized experiences from practitioners that have applied a resilience thinking approach to strategic planning, called Resilience Planning, in regional natural resource management organizations in Australia. This case represents one of the most extensive and long-term applications of resilience thinking in the world today. We conducted semi-structured interviews with Resilience Planning practitioners from nine organizations and reviewed strategic planning documents to investigate: 1) the key contributions of the approach to their existing strategic planning, and 2) what enabled and hindered the practitioners in applying and embedding the new approach in their organizations. Our results reveal that Resilience Planning contributed to developing a social-ecological systems perspective, more adaptive and collaborative approaches to planning, and that it clarified management goals of desirable resource conditions. Applying Resilience Planning required translating resilience thinking to practice in each unique circumstance, while simultaneously creating support among staff, and engaging external actors. Embedding Resilience Planning within organizations implied starting and maintaining longer-term change processes that required sustained multi-level organizational support. We conclude by identifying four lessons for successfully applying and embedding resilience practice in an organization: 1) to connect internal "entrepreneurs" to "interpreters" and "networkers" who work across organizations, 2) to assess the opportunity context for resilience practice, 3) to ensure that resilience practice is a learning process that engages internal and external actors, and 4) to develop reflective strategies for managing complexity and uncertainty. Copyright © 2018 The Authors
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Lucas, Morgan; Ilin, Yana; Anunu, Rachel; Kehat, Orli; Xu, Lin; Desmedt, Aline; Richter-Levin, Gal
2014-09-01
Findings suggest that stress-induced impaired learning and coping abilities may be attributed more to the psychological nature of the stressor, rather than its physical properties. It has been proposed that establishing controllability over stressors can ameliorate some of its effects on cognition and behavior. Gaining controllability was suggested to be associated with the development of stress resilience. Based on repeated exposure to the two-way shuttle avoidance task, we previously developed and validated a behavioral task that leads to a strict dissociation between gaining controllability (to the level that the associated fear is significantly reduced) and a fearful state of uncontrollability. Employing this protocol, we investigated here the impact of gaining or failing to gain emotional controllability on indices of anxiety and depression and on subsequent abilities to cope with positively or negatively reinforcing learning experiences. In agreement with previous studies, rats exposed to the uncontrollable protocol demonstrated high concentration of sera corticosterone, increased immobility, reduced duration of struggling in the forced swim test and impaired ability to acquire subsequent learning tasks. Achieving emotional controllability resulted in resilience to stress as was indicated by longer duration of struggling in the forced swim test, and enhanced learning abilities. Our prolonged training protocol, with the demonstrated ability of rats to gain emotional controllability, is proposed as a useful tool to study the neurobiological mechanisms of stress resilience.
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Gagliani, J.; Sorathia, U. A. K.; Wilcoxson, A. L.
1977-01-01
Materials were developed to improve aircraft interior materials by modifying existing polymer structures, refining the process parameters, and by the use of mechanical configurations designed to overcome specific deficiencies. The optimization, selection, and fabrication of five fire resistant, low smoke emitting open cell foams are described for five different types of aircraft cabin structures. These include: resilient foams, laminate floor and wall paneling, thermal/acoustical insulation, molded shapes, and coated fabrics. All five have been produced from essentially the same polyimide precursor and have resulted in significant benefits from transfer of technology between the various tasks.
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Childhood trauma and resilience in psoriatic patients: A preliminary report.
Crosta, Maria Luigia; De Simone, Clara; Di Pietro, Salvatore; Acanfora, Mariateresa; Caldarola, Giacomo; Moccia, Lorenzo; Callea, Antonino; Panaccione, Isabella; Peris, Ketty; Rinaldi, Lucio; Janiri, Luigi; Di Nicola, Marco
2018-03-01
Psoriasis is a chronic inflammatory skin disease with a complex etiology, involving the immune system, genetic factors, and external/internal triggers, with psychosomatic aspects. The aim of the study was to investigate childhood trauma and resilience in a psoriatic sample compared with healthy controls. Correlations between childhood trauma, resilience, quality of life, clinical data and psoriatic features were also evaluated. Seventy-seven psoriatic patients and seventy-six homogeneous healthy controls were enrolled. We used the Psoriasis Area and Severity Index (PASI) to assess the severity of psoriasis and the Skindex-29 to measure health-related quality of life. The psychometric battery included the Childhood Trauma Questionnaire (CTQ) and the Connor-Davidson Resilience Scale (CD-Risc) to assess trauma exposure and resilience, respectively. Psoriatic patients showed a significant prevalence of childhood trauma and a lower resilience level compared to healthy controls. Associations between traumatic experiences, low resilience and reduced quality of life in psoriatic subjects were also observed. A multidisciplinary approach is helpful to investigate clinical aspects, trigger factors and psychophysiological stress response in psoriatic subjects. Improving resilience with an early psychological intervention focused on self-motivation and strengthening of self-efficacy could facilitate the management of psoriasis. Copyright © 2018 Elsevier Inc. All rights reserved.
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Du, Hai; Shi, Zhiwei; Cheng, Keming; Wei, Dechen; Li, Zheng; Zhou, Danjie; He, Haibo; Yao, Junkai; He, Chengjun
2016-06-01
Vortex control is a thriving research area, particularly in relation to flying wing or delta wing aircraft. This paper presents the topological structures of vortex flow on a flying wing aircraft controlled by a nanosecond plasma dielectric barrier discharge actuator. Experiments, including oil flow visualization and two-dimensional particle image velocimetry (PIV), were conducted in a wind tunnel with a Reynolds number of 0.5 × 106. Both oil and PIV results show that the vortex can be controlled. Oil topological structures on the aircraft surface coincide with spatial PIV flow structures. Both indicate vortex convergence and enhancement when the plasma discharge is switched on, leading to a reduced region of separated flow.
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Fettered aircraft for using wind energy
Energy Technology Data Exchange (ETDEWEB)
Hoeppner, H.; Horvath, E.; Ulrich, S.
1980-08-28
The invention concerns an aircraft tethered by cables, whose balloon-shaped central body produces static and aerodynamic upthrust and which carries turbines, which are used to convert wind energy and to drive the aircraft. The purpose of the invention is to provide an aircraft, which will keep wind energy plant at the optimum height. A new type of aircraft is used to solve the problem, which, according to the invention, combines static upthrust, the production of aerodynamic upthrust, wind energy conversion, energy transport and forward drive in a technically integrated aircraft. If the use of windpower is interrupted, then if necessary the drive together with a remote control system provides controlled free flight of the aircraft. One variant of the object of the invention consists of a central, balloon-shaped body for upthrust, in which there are wind turbines driving electrical generators. According to the invention the motors required to start the wind turbines are of such dimensions that they will drive the turbines in free flight of the aircraft and thus provide forward drive of the aircraft. A power generating unit, consisting of an internal combustion engine and the starter motors switched over to generator operation is used to provide house service supplies for control and regulation of the aircraft.
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Gagliani, J.
1978-01-01
A new approach to the problem of flammability by the use of materials obtained from foamy polyimide resins is developed. The ability of these materials to provide fire protection is demonstrated. The development of processes for producing resilient cell foam for use in aircraft seating, thermal acoustical insulation, floor and wall panels, coated glass fabrics, and molded hardware.
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Directory of Open Access Journals (Sweden)
Gang eWu
2013-02-01
Full Text Available Resilience is the ability to adapt successfully in the face of stress and adversity. Stressful life events, trauma and chronic adversity can have a substantial impact on brain function and structure, and can result in the development of PTSD, depression and other psychiatric disorders. However, most individuals do not develop such illnesses after experiencing stressful life events, and are thus thought to be resilient. Resilience as successful adaptation relies on effective responses to environmental challenges and ultimate resistance to the deleterious effects of stress, therefore a greater understanding of the factors that promote such effects is of great relevance. This review focuses on recent findings regarding genetic, epigenetic, developmental, psychosocial and neurochemical factors that are considered essential contributors to the development of resilience. Neural circuits and pathways involved in mediating resilience are also discussed. The growing understanding of resilience factors will hopefully lead to the development of new pharmacological and psychological interventions for enhancing resilience and mitigating the untoward consequences.
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Iliff, Kenneth W.; Wang, Kon-Sheng Charles
1997-01-01
The results of parameter identification to determine the lateral-directional stability and control derivatives of an F-18 research aircraft in its basic hardware and software configuration are presented. The derivatives are estimated from dynamic flight data using a specialized identification program developed at NASA Dryden Flight Research Center. The formulation uses the linearized aircraft equations of motions in their continuous/discrete form and a maximum likelihood estimator that accounts for both state and measurement noise. State noise is used to model the uncommanded forcing function caused by unsteady aerodynamics, such as separated and vortical flows, over the aircraft. The derivatives are plotted as functions of angle of attack between 3 deg and 47 deg and compared with wind-tunnel predictions. The quality of the derivative estimates obtained by parameter identification is somewhat degraded because the maneuvers were flown with the aircraft's control augmentation system engaged, which introduced relatively high correlations between the control variables and response variables as a result of control motions from the feedback control system.
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Taylor, Zoe E.; Eisenberg, Nancy; Spinrad, Tracy L.; Widaman, Keith F.
2013-01-01
Longitudinal relations among ego-resiliency (ER), effortful control (EC), and observed intrusive parenting were examined at 18, 30, and 42 months of age ("Ns" = 256, 230, and 210) using structural equation modeling. Intrusive parenting at 18 and 30 months negatively predicted EC a year later, over and above earlier levels. EC at…
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Engine Yaw Augmentation for Hybrid-Wing-Body Aircraft via Optimal Control Allocation Techniques
Taylor, Brian R.; Yoo, Seung Yeun
2011-01-01
Asymmetric engine thrust was implemented in a hybrid-wing-body non-linear simulation to reduce the amount of aerodynamic surface deflection required for yaw stability and control. Hybrid-wing-body aircraft are especially susceptible to yaw surface deflection due to their decreased bare airframe yaw stability resulting from the lack of a large vertical tail aft of the center of gravity. Reduced surface deflection, especially for trim during cruise flight, could reduce the fuel consumption of future aircraft. Designed as an add-on, optimal control allocation techniques were used to create a control law that tracks total thrust and yaw moment commands with an emphasis on not degrading the baseline system. Implementation of engine yaw augmentation is shown and feasibility is demonstrated in simulation with a potential drag reduction of 2 to 4 percent. Future flight tests are planned to demonstrate feasibility in a flight environment.
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Bonnice, W. F.; Wagner, E.; Motyka, P.; Hall, S. R.
1985-01-01
The performance of the detection filter in detecting and isolating aircraft control surface and actuator failures is evaluated. The basic detection filter theory assumption of no direct input-output coupling is violated in this application due to the use of acceleration measurements for detecting and isolating failures. With this coupling, residuals produced by control surface failures may only be constrained to a known plane rather than to a single direction. A detection filter design with such planar failure signatures is presented, with the design issues briefly addressed. In addition, a modification to constrain the residual to a single known direction even with direct input-output coupling is also presented. Both the detection filter and the modification are tested using a nonlinear aircraft simulation. While no thresholds were selected, both filters demonstrated an ability to detect control surface and actuator failures. Failure isolation may be a problem if there are several control surfaces which produce similar effects on the aircraft. In addition, the detection filter was sensitive to wind turbulence and modeling errors.
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Directory of Open Access Journals (Sweden)
Widowati
2012-07-01
Full Text Available The applicability of parameter varying reduced order controllers to aircraft model is proposed. The generalization of the balanced singular perturbation method of linear time invariant (LTI system is used to reduce the order of linear parameter varying (LPV system. Based on the reduced order model the low-order LPV controller is designed by using synthesis technique. The performance of the reduced order controller is examined by applying it to lateral-directional control of aircraft model having 20th order. Furthermore, the time responses of the closed loop system with reduced order LPV controllers and reduced order LTI controller is compared. From the simulation results, the 8th order LPV controller can maintain stability and to provide the same level of closed-loop systems performance as the full-order LPV controller. It is different with the reduced-order LTI controller that cannot maintain stability and performance for all allowable parameter trajectories.
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Wing Shaping and Gust Load Controls of Flexible Aircraft: An LPV Approach
Hammerton, Jared R.; Su, Weihua; Zhu, Guoming; Swei, Sean Shan-Min
2018-01-01
In the proposed paper, the optimum wing shape of a highly flexible aircraft under varying flight conditions will be controlled by a linear parameter-varying approach. The optimum shape determined under multiple objectives, including flight performance, ride quality, and control effort, will be determined as well. This work is an extension of work done previously by the authors, and updates the existing optimization and utilizes the results to generate a robust flight controller.
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Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base
Mcruer, Duane T.; Myers, Thomas T.
1988-01-01
The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.
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Siebert, Al
2002-01-01
This article argues that school counselors cannot teach and preach resilient behavior if they are not models of resiliency themselves. Examines why some people come through challenging times more emotionally intact than others and suggests some tips for increasing one's resilience potential. (GCP)
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Application of Output Predictive Algorithmic Control to a Terrain Following Aircraft System.
1982-03-01
non-linear regime the results from an optimal control solution may be questionable. 15 -**—• - •*- "•—"".’" CHAPTER 3 Output Prpdirl- ivf ...strongly influenced by two other factors as well - the sample time T and the least-squares cost function Q. unlike the deadbeat control law of Ref...design of aircraft control systems since these methods offer tremendous insight into the dynamic behavior of the system at relatively low cost . However
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Adaptive neural network motion control for aircraft under uncertainty conditions
Efremov, A. V.; Tiaglik, M. S.; Tiumentsev, Yu V.
2018-02-01
We need to provide motion control of modern and advanced aircraft under diverse uncertainty conditions. This problem can be solved by using adaptive control laws. We carry out an analysis of the capabilities of these laws for such adaptive systems as MRAC (Model Reference Adaptive Control) and MPC (Model Predictive Control). In the case of a nonlinear control object, the most efficient solution to the adaptive control problem is the use of neural network technologies. These technologies are suitable for the development of both a control object model and a control law for the object. The approximate nature of the ANN model was taken into account by introducing additional compensating feedback into the control system. The capabilities of adaptive control laws under uncertainty in the source data are considered. We also conduct simulations to assess the contribution of adaptivity to the behavior of the system.
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Dynamics modeling and control of a transport aircraft for ultra-low altitude airdrop
Directory of Open Access Journals (Sweden)
Liu Ri
2015-04-01
Full Text Available The nonlinear aircraft model with heavy cargo moving inside is derived by using the separation body method, which can describe the influence of the moving cargo on the aircraft attitude and altitude accurately. Furthermore, the nonlinear system is decoupled and linearized through the input–output feedback linearization method. On this basis, an iterative quasi-sliding mode (SM flight controller for speed and pitch angle control is proposed. At the first-level SM, a global dynamic switching function is introduced thus eliminating the reaching phase of the sliding motion. At the second-level SM, a nonlinear function with the property of “smaller errors correspond to bigger gains and bigger errors correspond to saturated gains” is designed to form an integral sliding manifold, and the overcompensation of the integral term to big errors is weakened. Lyapunov-based analysis shows that the controller with strong robustness can reject both constant and time-varying model uncertainties. The performance of the proposed control strategy is verified in a maximum load airdrop mission.
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Aircraft Carrier Exposure Testing of Aircraft Materials
National Research Council Canada - National Science Library
Lee, Eui
2004-01-01
.... Test and control specimens were affixed on exposure racks and installed on aircraft carriers to compare adhesive bonding primers for aluminum and to determine the static property behavior of various...
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Robust Adaptive Neural Control of Morphing Aircraft with Prescribed Performance
Wu, Zhonghua; Lu, Jingchao; Shi, Jingping; Liu, Yang; Zhou, Qing
2017-01-01
This study proposes a low-computational composite adaptive neural control scheme for the longitudinal dynamics of a swept-back wing aircraft subject to parameter uncertainties. To efficiently release the constraint often existing in conventional neural designs, whose closed-loop stability analysis always necessitates that neural networks (NNs) be confined in the active regions, a smooth switching function is presented to conquer this issue. By integrating minimal learning parameter (MLP) tech...
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Directory of Open Access Journals (Sweden)
Saifullah Khalid
2016-09-01
Full Text Available Three conventional control constant instantaneous power control, sinusoidal current control, and synchronous reference frame techniques for extracting reference currents for shunt active power filters have been optimized using Fuzzy Logic control and Adaptive Tabu search Algorithm and their performances have been compared. Critical analysis of Comparison of the compensation ability of different control strategies based on THD and speed will be done, and suggestions will be given for the selection of technique to be used. The simulated results using MATLAB model are presented, and they will clearly prove the value of the proposed control method of aircraft shunt APF. The waveforms observed after the application of filter will be having the harmonics within the limits and the power quality will be improved.
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Comparative study of flare control laws. [optimal control of b-737 aircraft approach and landing
Nadkarni, A. A.; Breedlove, W. J., Jr.
1979-01-01
A digital 3-D automatic control law was developed to achieve an optimal transition of a B-737 aircraft between various initial glid slope conditions and the desired final touchdown condition. A discrete, time-invariant, optimal, closed-loop control law presented for a linear regulator problem, was extended to include a system being acted upon by a constant disturbance. Two forms of control laws were derived to solve this problem. One method utilized the feedback of integral states defined appropriately and augmented with the original system equations. The second method formulated the problem as a control variable constraint, and the control variables were augmented with the original system. The control variable constraint control law yielded a better performance compared to feedback control law for the integral states chosen.
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2016-04-05
the assessment of the health of a network or system. The hypothesis is: resiliency is meaningful in the context of holistic assessments of... health , holistic , Resiliency Tier, Resiliency Tier Matrix, State of Resiliency 295Defense ARJ, July 2015, Vol. 22 No. 3 : 294–324 296 Defense ARJ, July...upon who is speaking. Taking this one step further, consider resiliency as a concept that provides a holistic view of a system or capability, just
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Jalilianhasanpour, Rozita; Williams, Benjamin; Gilman, Isabelle; Burke, Matthew J; Glass, Sean; Fricchione, Gregory L; Keshavan, Matcheri S; LaFrance, W Curt; Perez, David L
2018-04-01
Reduced resilience, a construct associated with maladaptive stress coping and a predisposing vulnerability for Functional Neurological Disorders (FND), has been under-studied compared to other neuropsychiatric factors in FND. This prospective case-control study investigated self-reported resilience in patients with FND compared to controls and examined relationships between resilience and affective symptoms, personality traits, alexithymia, health status and adverse life event burden. 50 individuals with motor FND and 47 healthy controls participated. A univariate test followed by a logistic regression analysis investigated group-level differences in Connor-Davidson Resilience Scale (CD-RISC) scores. For within-group analyses performed separately in patients with FND and controls, univariate screening tests followed by multivariate linear regression analyses examined factors associated with self-reported resilience. Adjusting for age, gender, education status, ethnicity and lifetime adverse event burden, patients with FND reported reduced resilience compared to controls. Within-group analyses in patients with FND showed that individual-differences in mental health, extraversion, conscientiousness, and openness positively correlated with CD-RISC scores; post-traumatic stress disorder symptom severity, depression, anxiety, alexithymia and neuroticism scores negatively correlated with CD-RISC scores. Extraversion independently predicted resilience scores in patients with FND. In control subjects, univariate associations were appreciated between CD-RISC scores and gender, personality traits, anxiety, alexithymia and physical health; conscientiousness independently predicted resilience in controls. Patients with FND reported reduced resilience, and CD-RISC scores covaried with other important predisposing vulnerabilities for the development of FND. Future research should investigate if the CD-RISC is predictive of clinical outcomes in patients with FND. Copyright
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Rothhaar, Paul M.; Murphy, Patrick C.; Bacon, Barton J.; Gregory, Irene M.; Grauer, Jared A.; Busan, Ronald C.; Croom, Mark A.
2014-01-01
Control of complex Vertical Take-Off and Landing (VTOL) aircraft traversing from hovering to wing born flight mode and back poses notoriously difficult modeling, simulation, control, and flight-testing challenges. This paper provides an overview of the techniques and advances required to develop the GL-10 tilt-wing, tilt-tail, long endurance, VTOL aircraft control system. The GL-10 prototype's unusual and complex configuration requires application of state-of-the-art techniques and some significant advances in wind tunnel infrastructure automation, efficient Design Of Experiments (DOE) tunnel test techniques, modeling, multi-body equations of motion, multi-body actuator models, simulation, control algorithm design, and flight test avionics, testing, and analysis. The following compendium surveys key disciplines required to develop an effective control system for this challenging vehicle in this on-going effort.
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International Nuclear Information System (INIS)
Lundberg, Jonas; Johansson, Björn JE
2015-01-01
It has been realized that resilience as a concept involves several contradictory definitions, both for instance resilience as agile adjustment and as robust resistance to situations. Our analysis of resilience concepts and models suggest that beyond simplistic definitions, it is possible to draw up a systemic resilience model (SyRes) that maintains these opposing characteristics without contradiction. We outline six functions in a systemic model, drawing primarily on resilience engineering, and disaster response: anticipation, monitoring, response, recovery, learning, and self-monitoring. The model consists of four areas: Event-based constraints, Functional Dependencies, Adaptive Capacity and Strategy. The paper describes dependencies between constraints, functions and strategies. We argue that models such as SyRes should be useful both for envisioning new resilience methods and metrics, as well as for engineering and evaluating resilient systems. - Highlights: • The SyRes model resolves contradictions between previous resilience definitions. • SyRes is a core model for envisioning and evaluating resilience metrics and models. • SyRes describes six functions in a systemic model. • They are anticipation, monitoring, response, recovery, learning, self-monitoring. • The model describes dependencies between constraints, functions and strategies
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Predicting visibility of aircraft.
Directory of Open Access Journals (Sweden)
Andrew Watson
Full Text Available Visual detection of aircraft by human observers is an important element of aviation safety. To assess and ensure safety, it would be useful to be able to be able to predict the visibility, to a human observer, of an aircraft of specified size, shape, distance, and coloration. Examples include assuring safe separation among aircraft and between aircraft and unmanned vehicles, design of airport control towers, and efforts to enhance or suppress the visibility of military and rescue vehicles. We have recently developed a simple metric of pattern visibility, the Spatial Standard Observer (SSO. In this report we examine whether the SSO can predict visibility of simulated aircraft images. We constructed a set of aircraft images from three-dimensional computer graphic models, and measured the luminance contrast threshold for each image from three human observers. The data were well predicted by the SSO. Finally, we show how to use the SSO to predict visibility range for aircraft of arbitrary size, shape, distance, and coloration.
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EPA adopted emission standards and related provisions for aircraft gas turbine engines with rated thrusts greater than 26.7 kilonewtons. These engines are used primarily on commercial passenger and freight aircraft.
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Neural adaptive control for vibration suppression in composite fin-tip of aircraft.
Suresh, S; Kannan, N; Sundararajan, N; Saratchandran, P
2008-06-01
In this paper, we present a neural adaptive control scheme for active vibration suppression of a composite aircraft fin tip. The mathematical model of a composite aircraft fin tip is derived using the finite element approach. The finite element model is updated experimentally to reflect the natural frequencies and mode shapes very accurately. Piezo-electric actuators and sensors are placed at optimal locations such that the vibration suppression is a maximum. Model-reference direct adaptive neural network control scheme is proposed to force the vibration level within the minimum acceptable limit. In this scheme, Gaussian neural network with linear filters is used to approximate the inverse dynamics of the system and the parameters of the neural controller are estimated using Lyapunov based update law. In order to reduce the computational burden, which is critical for real-time applications, the number of hidden neurons is also estimated in the proposed scheme. The global asymptotic stability of the overall system is ensured using the principles of Lyapunov approach. Simulation studies are carried-out using sinusoidal force functions of varying frequency. Experimental results show that the proposed neural adaptive control scheme is capable of providing significant vibration suppression in the multiple bending modes of interest. The performance of the proposed scheme is better than the H(infinity) control scheme.
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Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program
Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter
1994-01-01
The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.
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Intelligent Materials Used in Hydraulic, Fuel, and Rudder Control Systems of Aircrafts
Directory of Open Access Journals (Sweden)
D. B. Chernov
2017-01-01
Full Text Available The device is really intelligent, only if it is capable to respond to changing external conditions. The devices, which "feel" the external environment and can change their characteristics, have many advantages compared to the conventional devices: they are more efficient, wear out more slowly, and have lower operating costs.The scope of smart products is truly infinite. Alloys with memory effect also apply to intellectual content. Natural piezoelectric crystals such as silicon dioxide (intellectual material have been known for over a hundred years. They have greater stiffness and can be used at high operating frequencies. Due to the direct piezoelectric effect, they have been successfully used as a strain gage. Later came artificial ceramic piezoelectric materials; they are used as mechanical transducers. Thus, an inverse piezoelectric effect is usually used. It consists in the change of dimensions when an electric field is applied. Control of intellectual structure can be provided by heat fluxes, electromagnetic, hydraulic or piezoelectric forces and through application of electro-rheological, and magneto-rheological fluids. The article examines the intellectual materials and technologies that are already in place or will find its application in aviation hydraulic and fuel systems and control systems of rudders (CSR of aircrafts in the near future.The paper considers in detail the shape memory effect alloys (SMEA as "intelligent" materials. Actuators made from SMEA have a number of advantages: high working power; large recoverable deformation; different types of strain (tensile, compressive, bending and torsional; most specific value of the work per unit mass. All the SMEA advantages may be well used for the so-called thermo-mechanical connections (TMС of pipelines where SMEA drawbacks in this application, practically, do not affect the quality of TMC. In aircraft engineering the TMC were first used in hydraulic systems of the aircraft TU204
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2011-09-07
... with an electronic engine control (EEC), also known as a Full Authority Digital Engine Control (FADEC... engine design certification, and the certification requirements for engine control systems are driven by... aircraft supplied power and data failures on the engine control system, and the resulting effects on engine...
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Psychological Trait Resilience Within Ecological Systems Theory: The Resilient Systems Scales.
Maltby, John; Day, Liz; Flowe, Heather D; Vostanis, Panos; Chivers, Sally
2017-07-14
This project describes the development of the Resilient Systems Scales, created to address conceptual and methodological ambiguities in assessing the ecological systems model of resilience. Across a number of samples (total N = 986), our findings suggest that the Resilient Systems Scales show equivalence to a previously reported assessment (Maltby, Day, & Hall, 2015 ) in demonstrating the same factor structure, adequate intercorrelation between the 2 measures of resilience, and equivalent associations with personality and well-being. The findings also suggest that the Resilient Systems Scales demonstrate adequate test-retest reliability, compare well with other extant measures of resilience in predicting well-being, and map, to varying degrees, onto positive expression of several cognitive, social, and emotional traits. The findings suggest that the new measure can be used alongside existing measures of resilience, or singly, to assess positive life outcomes within psychology research.
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Reveley, Mary s.; Briggs, Jeffrey L.; Leone, Karen M.; Kurtoglu, Tolga; Withrow, Colleen A.
2010-01-01
Literature from academia, industry, and other Government agencies was surveyed to assess the state of the art in current Integrated Resilient Aircraft Control (IRAC) aircraft technologies. Over 100 papers from 25 conferences from the time period 2004 to 2009 were reviewed. An assessment of the general state of the art in adaptive flight control is summarized first, followed by an assessment of the state of the art as applicable to 13 identified adverse conditions. Specific areas addressed in the general assessment include flight control when compensating for damage or reduced performance, retrofit software upgrades to flight controllers, flight control through engine response, and finally test and validation of new adaptive controllers. The state-of-the-art assessment applicable to the adverse conditions include technologies not specifically related to flight control, but may serve as inputs to a future flight control algorithm. This study illustrates existing gaps and opportunities for additional research by the NASA IRAC Project
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Resilient leadership and the organizational culture of resilience: construct validation.
Everly, George S; Smith, Kenneth J; Lobo, Rachel
2013-01-01
Political, economic, and social unrest and uncertainty seem replete throughout the world. Within the United States, political vitriol and economic volatility have led to severe economic restrictions. Both government and private sector organizations are being asked to do more with less. The specter of dramatic changes in healthcare creates a condition of uncertainty affecting budget allocations and hiring practices. If ever there was a time when a "resilient culture" was needed, it is now. In this paper we shall discuss the application of "tipping point" theory (Gladwell, 2000) operationalized through a special form of leadership: "resilient leadership" (Everly, Strouse, Everly, 2010). Resilient leadership is consistent with Gladwells "Law of the Few" and strives to create an organizational culture of resilience by implementing an initial change within no more than 20% of an organization's workforce. It is expected that such a minority, if chosen correctly, will "tip" the rest of the organization toward enhanced resilience, ideally creating a self-sustaining culture of resilience. This paper reports on the empirical foundations and construct validation of "resilient leadership".
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Smith, G. A.; Meyer, G.
1981-01-01
A full envelope automatic flight control system based on nonlinear inverse systems concepts has been applied to a vertical attitude takeoff and landing (VATOL) fighter aircraft. A new method for using an airborne digital aircraft model to perform the inversion of a nonlinear aircraft model is presented together with the results of a simulation study of the nonlinear inverse system concept for the vertical-attitude hover mode. The system response to maneuver commands in the vertical attitude was found to be excellent; and recovery from large initial offsets and large disturbances was found to be very satisfactory.
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Fisheries regulatory regimes and resilience to climate change.
Ojea, Elena; Pearlman, Isaac; Gaines, Steven D; Lester, Sarah E
2017-05-01
Climate change is already producing ecological, social, and economic impacts on fisheries, and these effects are expected to increase in frequency and magnitude in the future. Fisheries governance and regulations can alter socio-ecological resilience to climate change impacts via harvest control rules and incentives driving fisher behavior, yet there are no syntheses or conceptual frameworks for examining how institutions and their regulatory approaches can alter fisheries resilience to climate change. We identify nine key climate resilience criteria for fisheries socio-ecological systems (SES), defining resilience as the ability of the coupled system of interacting social and ecological components (i.e., the SES) to absorb change while avoiding transformation into a different undesirable state. We then evaluate the capacity of four fisheries regulatory systems that vary in their degree of property rights, including open access, limited entry, and two types of rights-based management, to increase or inhibit resilience. Our exploratory assessment of evidence in the literature suggests that these regulatory regimes vary widely in their ability to promote resilient fisheries, with rights-based approaches appearing to offer more resilience benefits in many cases, but detailed characteristics of the regulatory instruments are fundamental.
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Resilience is an important framework for understanding and managing complex systems of people and nature that are subject to abrupt and nonlinear change. The idea of ecological resilience was slow to gain acceptance in the scientific community, taking thirty years to become widel...
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The Effect of Modified Control Limits on the Performance of a Generic Commercial Aircraft Engine
Csank, Jeffrey T.; May, Ryan D.; Gou, Ten-Huei; Litt, Jonathan S.
2012-01-01
This paper studies the effect of modifying the control limits of an aircraft engine to obtain additional performance. In an emergency situation, the ability to operate an engine above its normal operating limits and thereby gain additional performance may aid in the recovery of a distressed aircraft. However, the modification of an engine s limits is complex due to the risk of an engine failure. This paper focuses on the tradeoff between enhanced performance and risk of either incurring a mechanical engine failure or compromising engine operability. The ultimate goal is to increase the engine performance, without a large increase in risk of an engine failure, in order to increase the probability of recovering the distressed aircraft. The control limit modifications proposed are to extend the rotor speeds, temperatures, and pressures to allow more thrust to be produced by the engine, or to increase the rotor accelerations and allow the engine to follow a fast transient. These modifications do result in increased performance; however this study indicates that these modifications also lead to an increased risk of engine failure.
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MD-11 PCA - View of aircraft on ramp
1995-01-01
This McDonnell Douglas MD-11 is taxiing to a position on the flightline at NASA's Dryden Flight Research Center, Edwards, California, following its completion of the first and second landings ever performed by a transport aircraft under engine power only (on Aug. 29, 1995). The milestone flight, with NASA research pilot and former astronaut Gordon Fullerton at the controls, was part of a NASA project to develop a computer-assisted engine control system that enables a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft (PCA) system uses standard autopilot controls already present in the cockpit, together with the new programming in the aircraft's flight control computers. The PCA concept is simple. For pitch control, the program increases thrust to climb and reduces thrust to descend. To turn right, the autopilot increases the left engine thrust while decreasing the right engine thrust. The initial Propulsion-Controlled Aircraft studies by NASA were carried out at Dryden with a modified twin-engine F-15 research aircraft.
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Adaptive Flight Control Research at NASA
Motter, Mark A.
2008-01-01
A broad overview of current adaptive flight control research efforts at NASA is presented, as well as some more detailed discussion of selected specific approaches. The stated objective of the Integrated Resilient Aircraft Control Project, one of NASA s Aviation Safety programs, is to advance the state-of-the-art of adaptive controls as a design option to provide enhanced stability and maneuverability margins for safe landing in the presence of adverse conditions such as actuator or sensor failures. Under this project, a number of adaptive control approaches are being pursued, including neural networks and multiple models. Validation of all the adaptive control approaches will use not only traditional methods such as simulation, wind tunnel testing and manned flight tests, but will be augmented with recently developed capabilities in unmanned flight testing.
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Directory of Open Access Journals (Sweden)
Ioan ŞTEFĂNESCU
2011-03-01
Full Text Available Converting the DC school jet aircraft into SC advanced training aircraft - and use them forthe combat training of military pilots from the operational units, has become a necessity due to thebudget cuts for Air Force, with direct implications on reducing the number of hours of flight assignedto operating personnel for preparing and training.The purpose of adopting such a program is to reduce the number of flight hours allocated annuallyfor preparing and training in advanced stages of instruction, for every pilot, by more intensive use ofthis type of aircraft, which has the advantage of lower flight hour costs as compared to a supersoniccombat plane.
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Developing the resilience typology
DEFF Research Database (Denmark)
Simonsen, Daniel Morten
2013-01-01
There is a growing interest in resilience in internal crisis management and crisis communication. How an organization can build up resilience as a response to organisational crisis, at a time when the amount of crises seem only to increase, is more relevant than ever before. Nevertheless resilience...... is often perceived in the literature as something certain organisations have by definition, without further reflection on what it is that creates this resiliency. This article explores what it is that creates organisational resilience, and in view of the different understandings of the resilience...... phenomenon, develops a typology of resilience. Furthermore the resilience phenomenon is discussed against the definition of a crisis as a cosmological episode, and implications for future research is discussed and summarized....
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Seeding Stress Resilience through Inoculation
Directory of Open Access Journals (Sweden)
Archana Ashokan
2016-01-01
Full Text Available Stress is a generalized set of physiological and psychological responses observed when an organism is placed under challenging circumstances. The stress response allows organisms to reattain the equilibrium in face of perturbations. Unfortunately, chronic and/or traumatic exposure to stress frequently overwhelms coping ability of an individual. This is manifested as symptoms affecting emotions and cognition in stress-related mental disorders. Thus environmental interventions that promote resilience in face of stress have much clinical relevance. Focus of the bulk of relevant neurobiological research at present remains on negative aspects of health and psychological outcomes of stress exposure. Yet exposure to the stress itself can promote resilience to subsequent stressful episodes later in the life. This is especially true if the prior stress occurs early in life, is mild in its magnitude, and is controllable by the individual. This articulation has been referred to as “stress inoculation,” reminiscent of resilience to the pathology generated through vaccination by attenuated pathogen itself. Using experimental evidence from animal models, this review explores relationship between nature of the “inoculum” stress and subsequent psychological resilience.
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'Resilience thinking' in transport planning
Wang, JYT
2015-01-01
Resilience has been discussed in ecology for over forty years. While some aspects of resilience have received attention in transport planning, there is no unified definition of resilience in transportation. To define resilience in transportation, I trace back to the origin of resilience in ecology with a view of revealing the essence of resilience thinking and its relevance to transport planning. Based on the fundamental concepts of engineering resilience and ecological resilience, I define "...
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AIRCRAFT CONFLICTS RESOLUTION BY COURSE MANEUVERING
Directory of Open Access Journals (Sweden)
В. Харченко
2011-02-01
Full Text Available Enhancement of requirements for air traffic efficiency at increasing of flights intensity determines the necessity of development of new optimization methods for aircraft conflict resolutions. The statement of problem of optimal conflict resolutions at Cooperative Air Traffic Management was done. The method for optimal aircraft conflict resolution by course maneuvering has been developed. The method using dynamic programming provides planning of aircraft conflict-free trajectory with minimum length. The decomposition of conflict resolution process on phases and stages, definition of states, controls and recursive equations for generation of optimal course control program were done. Computer modeling of aircraft conflict resolution by developed method was done
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Four concepts for resilience and the implications for the future of resilience engineering
International Nuclear Information System (INIS)
Woods, David D.
2015-01-01
The concept of system resilience is important and popular—in fact, hyper-popular over the last few years. Clarifying the technical meanings and foundations of the concept of resilience would appear to be necessary. Proposals for defining resilience are flourishing as well. This paper organizes the different technical approaches to the question of what is resilience and how to engineer it in complex adaptive systems. This paper groups the different uses of the label ‘resilience’ around four basic concepts: (1) resilience as rebound from trauma and return to equilibrium; (2) resilience as a synonym for robustness; (3) resilience as the opposite of brittleness, i.e., as graceful extensibility when surprise challenges boundaries; (4) resilience as network architectures that can sustain the ability to adapt to future surprises as conditions evolve. - Highlights: • There continues to be a wide diversity of definitions of the label resilience. • Research progress points to 4 basic concepts underneath diverse uses of. • Each of the four core concepts defines different research agendas. • The 4 concepts provide guides on how to engineer resilience for safety
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Kotila, Saara M; Payne Hallström, Lara; Jansen, Niesje; Helbling, Peter; Abubakar, Ibrahim
2016-01-01
As a setting for potential tuberculosis (TB) transmission and contact tracing, aircraft pose specific challenges. Evidence-based guidelines are needed to support the related-risk assessment and contact-tracing efforts. In this study evidence of TB transmission on aircraft was identified to update the Risk Assessment Guidelines for TB Transmitted on Aircraft (RAGIDA-TB) of the European Centre for Disease Prevention and Control (ECDC). Electronic searches were undertaken from Medline (Pubmed), Embase and Cochrane Library until 19 July 2013. Eligible records were identified by a two-stage screening process and data on flight and index case characteristics as well as contact tracing strategies extracted. The systematic literature review retrieved 21 records. Ten of these records were available only after the previous version of the RAGIDA guidelines (2009) and World Health Organization guidelines on TB and air travel (2008) were published. Seven of the 21 records presented some evidence of possible in-flight transmission, but only one record provided substantial evidence of TB transmission on an aircraft. The data indicate that overall risk of TB transmission on aircraft is very low. The updated ECDC guidelines for TB transmission on aircraft have global implications due to inevitable need for international collaboration in contract tracing and risk assessment.
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A discussion on the resilience of command and control regulation within regulatory behavior theories
Directory of Open Access Journals (Sweden)
K.P.V. O’Sullivan
2012-03-01
Full Text Available This paper provides the first insights into the factors that may drive the resilience of command and control regulation in modern policy making. We show how the forces of uncertainty and internal dynamics among customers, producers and regulators are the most dominate factors preventing the adoption of non-CAC regulations. Using case study evidence of internet regulation, we then integrate our analysis into the most prominent regulatory choice behavior theories and illustrate that regardless of the theory, these factors can help explain the dominance of command and control as a choice of regulation.
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Design, Specification, and Synthesis of Aircraft Electric Power Systems Control Logic
Xu, Huan
Cyber-physical systems integrate computation, networking, and physical processes. Substantial research challenges exist in the design and verification of such large-scale, distributed sensing, actuation, and control systems. Rapidly improving technology and recent advances in control theory, networked systems, and computer science give us the opportunity to drastically improve our approach to integrated flow of information and cooperative behavior. Current systems rely on text-based specifications and manual design. Using new technology advances, we can create easier, more efficient, and cheaper ways of developing these control systems. This thesis will focus on design considerations for system topologies, ways to formally and automatically specify requirements, and methods to synthesize reactive control protocols, all within the context of an aircraft electric power system as a representative application area. This thesis consists of three complementary parts: synthesis, specification, and design. The first section focuses on the synthesis of central and distributed reactive controllers for an aircraft elec- tric power system. This approach incorporates methodologies from computer science and control. The resulting controllers are correct by construction with respect to system requirements, which are formulated using the specification language of linear temporal logic (LTL). The second section addresses how to formally specify requirements and introduces a domain-specific language for electric power systems. A software tool automatically converts high-level requirements into LTL and synthesizes a controller. The final sections focus on design space exploration. A design methodology is proposed that uses mixed-integer linear programming to obtain candidate topologies, which are then used to synthesize controllers. The discrete-time control logic is then verified in real-time by two methods: hardware and simulation. Finally, the problem of partial observability and
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Directory of Open Access Journals (Sweden)
Thomas A. Birkland
2016-12-01
Full Text Available This commentary provides an overview of the idea of resilience, and acknowledges the challenges of defining and applying the idea in practice. The article summarizes a way of looking at resilience called a “resilience delta”, that takes into account both the shock done to a community by a disaster and the capacity of that community to rebound from that shock to return to its prior functionality. I show how different features of the community can create resilience, and consider how the developed and developing world addresses resilience. I also consider the role of focusing events in gaining attention to events and promoting change. I note that, while focusing events are considered by many in the disaster studies field to be major drivers of policy change in the United States disaster policy, most disasters have little effect on the overall doctrine of shared responsibilities between the national and subnational governments.
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Systematic analysis of aircraft separation requirements
Ennis, Rachelle Lea
2005-12-01
Minimum separation standards are necessary for safety in the air traffic control system. At the same time, minimum separation standards constrain the flow of air traffic and cause delays that translate to millions of dollars in fuel costs. Two necessary separation standards are defined. Then, practical methods for calculating the minimum required size of these separation standards are presented. First, the protected zone is considered. The protected zone represents a region around a given aircraft that no other aircraft should penetrate for the safety of both aircraft. It defines minimum separation requirements. Three major components of the protected zone and their interplays are identified: a vortex region, a safety buffer region, and a state-uncertainty region. A systematic procedure is devised for the analysis of the state-uncertainty region. In particular, models of trajectory controls are developed that can be used to represent different modes of pilot and/or autopilot controls, such as path feedback and non-path feedback. Composite protected zones under various conditions are estimated, and effective ways to reduce sizes of protected zones for advanced air traffic management are examined. In order to maintain minimum separation standards between two aircraft, proper avoidance maneuvers must be initiated before their relative separation reaches the minimum separation due to aircraft dynamics, controller and pilot response delays, etc. The concept of the required action threshold is presented. It is defined as the advanced time for which the conflict resolution process must begin in order to maintain minimum separation requirements. Five main segments in the process of conflict resolution are identified, discussed, and modeled: state information acquisition, comprehension and decision, communication, pilot response, and aircraft maneuver. Each of the five segments is modeled via a time constant. Time estimates for the first four segments are obtained from
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Association between morningness and resilience in Korean college students.
Lee, So-Jin; Park, Chul-Soo; Kim, Bong-Jo; Lee, Cheol-Soon; Cha, Boseok; Lee, Yu Jin; Soh, Minah; Park, Jin Ah; Young, Park So; Song, Eun Hye
2016-01-01
Circadian typology and sleep quality may be essential factors associated with the promotion of resilience. However, previous studies investigating the association between circadian typology and resilience did not analyze the effects of sleep quality on resilience. Thus, the present study evaluated the association between circadian typology and resilience in Korean college students after controlling for sleep quality. Additionally, this study investigated several sleep-related variables, including sleep duration, social jetlag and sunlight exposure during the daytime, to examine the modifiable behavioral features of morningness and also investigated whether the findings regarding morningness-related modifiable habits were associated with resilience. This study included 1094 participants (947 males and 147 females) between 19 and 29 years of age (22.8 ± 1.9 years) who completed the 10-item Korean version of the Connor-Davidson Resilience Scale (CD-RISC-10), the Korean version of the Morningness-Eveningness Questionnaire (MEQ), the Pittsburgh Sleep Quality Index (PSQI), the Korean version of the Hospital Anxiety and Depression Scale (HADS) and a survey about social jetlag that determined misalignments between weekday and weekend times of awakening and activity duration under conditions of sunlight between 10:00 and 15:00. A multiple linear regression analysis revealed that sleep duration, mean daily sunlight exposure between 10:00 and 15:00 and age were positive predictors of morningness, whereas social jetlag was a negative predictor of morningness. Of these morningness-related modifiable behavioral features, mean daily sunlight exposure between 10:00 and 15:00 significantly predicted greater resilience. An additional multiple linear regression analysis revealed that morningness was a positive predictor of resilience after controlling for age, sex, depression, anxiety and sleep quality. These results support the idea that morningness and better sleep quality are
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Robust Adaptive Neural Control of Morphing Aircraft with Prescribed Performance
Directory of Open Access Journals (Sweden)
Zhonghua Wu
2017-01-01
Full Text Available This study proposes a low-computational composite adaptive neural control scheme for the longitudinal dynamics of a swept-back wing aircraft subject to parameter uncertainties. To efficiently release the constraint often existing in conventional neural designs, whose closed-loop stability analysis always necessitates that neural networks (NNs be confined in the active regions, a smooth switching function is presented to conquer this issue. By integrating minimal learning parameter (MLP technique, prescribed performance control, and a kind of smooth switching strategy into back-stepping design, a new composite switching adaptive neural prescribed performance control scheme is proposed and a new type of adaptive laws is constructed for the altitude subsystem. Compared with previous neural control scheme for flight vehicle, the remarkable feature is that the proposed controller not only achieves the prescribed performance including transient and steady property but also addresses the constraint on NN. Two comparative simulations are presented to verify the effectiveness of the proposed controller.
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Social-ecological resilience and geomorphic systems
Chaffin, Brian C.; Scown, Murray
2018-03-01
can play formative roles during periods of collapse and reorganization. Large- and small-scale disturbances as well as large-scale system memory/capacity and small-scale innovation can have significant impacts on the trajectory of a reorganizing system (Gunderson and Holling, 2002; Chaffin and Gunderson, 2016). Attempts to measure the property of ecological resilience across complex systems amounts to attempts to measure the persistence of system-controlling variables, including processes, parameters, and important feedbacks, when the system is exposed to varying degrees of disturbance (Folke, 2016).
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Analyses of Aircraft Responses to Atmospheric Turbulence
Van Staveren, W.H.J.J.
2003-01-01
The response of aircraft to stochastic atmospheric turbulence plays an important role in aircraft-design (load calculations), Flight Control System (FCS) design and flight-simulation (handling qualities research and pilot training). In order to simulate these aircraft responses, an accurate
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Science and Technology at DHS: Resiliency of our Physical and Social Infrastructure
Energy Technology Data Exchange (ETDEWEB)
Erickson, Mitchel
2012-04-11
Disasters affect us all. The challenge is to minimize the impact. Resilience has been defined as “Foster individual, community, and system robustness, adaptability, and capacity for rapid recovery.” The Department of Homeland Security’s (DHS) Science and Technology Directorate (S&T) provides new technologies, materials, controls, models, and other tools that promote resilience. More important, science and technology can contribute to shaping our resiliency blueprint by instilling scientific rigor into the processes that will shape our future. This presentation will review resiliency approaches, emerging technologies, and capability gaps for resilient communities and institutions.
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Directory of Open Access Journals (Sweden)
Birutė PITRĖNAITĖ-ŽILĖNIENĖ
2014-12-01
Full Text Available Rising complexity, numbers and severity of natural and manmade disasters enhance the importance of reducing vulnerability, or on contrary – increasing resilience, of different kind of systems, including those of social, engineering (infrastructure, and environmental (ecological nature. The goal of this research is to explore urban resilience as an integral system of social, environmental, and engineering resilience. This report analyses the concepts of each kind of resilience and identifies key factors influencing social, ecological, and infrastructure resilience discussing how these factors relate within urban systems. The achievement of resilience of urban and regional systems happens through the interaction of the different elements (social, psychological, physical, structural, and environmental, etc.; therefore, resilient city could be determined by synergy of resilient society, resilient infrastructure and resilient environment of the given area. Based on literature analysis, the current research provides some insights on conceptual framework for assessment of complex urban systems in terms of resilience. To be able to evaluate resilience and define effective measures for prevention and risk mitigation, and thereby strengthen resilience, we propose to develop an e-platform, joining risk parameters’ Monitoring Systems, which feed with data Resiliency Index calculation domain. Both these elements result in Multirisk Platform, which could serve for awareness and shared decision making for resilient people in resilient city.
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Quantifying resilience for resilience engineering of socio technical systems
Häring, Ivo; Ebenhöch, Stefan; Stolz, Alexander
2016-01-01
Resilience engineering can be defined to comprise originally technical, engineering and natural science approaches to improve the resilience and sustainability of socio technical cyber-physical systems of various complexities with respect to disruptive events. It is argued how this emerging interdisciplinary technical and societal science approach may contribute to civil and societal security research. In this context, the article lists expected benefits of quantifying resilience. Along the r...
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Knowledge-based scheduling of arrival aircraft
Krzeczowski, K.; Davis, T.; Erzberger, H.; Lev-Ram, I.; Bergh, C.
1995-01-01
A knowledge-based method for scheduling arrival aircraft in the terminal area has been implemented and tested in real-time simulation. The scheduling system automatically sequences, assigns landing times, and assigns runways to arrival aircraft by utilizing continuous updates of aircraft radar data and controller inputs. The scheduling algorithms is driven by a knowledge base which was obtained in over two thousand hours of controller-in-the-loop real-time simulation. The knowledge base contains a series of hierarchical 'rules' and decision logic that examines both performance criteria, such as delay reduction, as well as workload reduction criteria, such as conflict avoidance. The objective of the algorithms is to devise an efficient plan to land the aircraft in a manner acceptable to the air traffic controllers. This paper will describe the scheduling algorithms, give examples of their use, and present data regarding their potential benefits to the air traffic system.
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İnci, Fadime Hatice; Temel, Ayla Bayik
2016-11-01
The purpose of the study was to determine the effect of a support program on the resilience of female family caregivers of stroke patients. This is a randomized controlled trial. The sample consisted 70 female family caregivers (34 experimental, 36 control group). Data were collected three times (pretest-posttest, follow-up test). Data were collected using the demographical data form, the Family Index of Regenerativity and Adaptation-General. A significant difference was determined between the experimental and control group's follow-up test scores for relative and friend support, social support and family-coping coherence. A significant difference was determined between the experimental group's mean pretest, posttest and follow-up test scores in terms of family strain, relative and friend support, social support, family coping-coherence, family hardiness and family distress. These results suggest that the Support Program contributes to the improvement of the components of resilience of family caregivers of stroke patients. Copyright © 2016 Elsevier Inc. All rights reserved.
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Analyzing Resiliency of the Smart Grid Communication Architectures
Energy Technology Data Exchange (ETDEWEB)
None, None
2016-08-01
Smart grids are susceptible to cyber-attack as a result of new communication, control and computation techniques employed in the grid. In this paper, we characterize and analyze the resiliency of smart grid communication architecture, specifically an RF mesh based architecture, under cyber attacks. We analyze the resiliency of the communication architecture by studying the performance of high-level smart grid functions such as metering, and demand response which depend on communication. Disrupting the operation of these functions impacts the operational resiliency of the smart grid. Our analysis shows that it takes an attacker only a small fraction of meters to compromise the communication resiliency of the smart grid. We discuss the implications of our result to critical smart grid functions and to the overall security of the smart grid.
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Resilience: Theory and Application.
Energy Technology Data Exchange (ETDEWEB)
Carlson, J.L.; Haffenden, R.A.; Bassett, G.W.; Buehring, W.A.; Collins, M.J., III; Folga, S.M.; Petit, F.D.; Phillips, J.A.; Verner, D.R.; Whitfield, R.G. (Decision and Information Sciences)
2012-02-03
There is strong agreement among policymakers, practitioners, and academic researchers that the concept of resilience must play a major role in assessing the extent to which various entities - critical infrastructure owners and operators, communities, regions, and the Nation - are prepared to respond to and recover from the full range of threats they face. Despite this agreement, consensus regarding important issues, such as how resilience should be defined, assessed, and measured, is lacking. The analysis presented here is part of a broader research effort to develop and implement assessments of resilience at the asset/facility and community/regional levels. The literature contains various definitions of resilience. Some studies have defined resilience as the ability of an entity to recover, or 'bounce back,' from the adverse effects of a natural or manmade threat. Such a definition assumes that actions taken prior to the occurrence of an adverse event - actions typically associated with resistance and anticipation - are not properly included as determinants of resilience. Other analyses, in contrast, include one or more of these actions in their definitions. To accommodate these different definitions, we recognize a subset of resistance- and anticipation-related actions that are taken based on the assumption that an adverse event is going to occur. Such actions are in the domain of resilience because they reduce both the immediate and longer-term adverse consequences that result from an adverse event. Recognizing resistance- and anticipation-related actions that take the adverse event as a given accommodates the set of resilience-related actions in a clear-cut manner. With these considerations in mind, resilience can be defined as: 'the ability of an entity - e.g., asset, organization, community, region - to anticipate, resist, absorb, respond to, adapt to, and recover from a disturbance.' Because critical infrastructure resilience is important
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Aircraft Command Control Communications and Navigation Systems, AFSC 2A4X3, OSSN: 2308
National Research Council Canada - National Science Library
1998-01-01
1. Survey Coverage: The Aircraft Command Control Communications and Navigation Systems career ladder was surveyed to provide current job and task data for use in updating career ladder documents and training programs...
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Resilience research in schizophrenia: a review of recent developments.
Mizuno, Yuya; Wartelsteiner, Fabienne; Frajo-Apor, Beatrice
2016-05-01
The concept of resilience is expected to be relevant in understanding the heterogeneous outcomes associated with schizophrenia. We reviewed recent developments in clinical studies focusing on the biological and psychological aspects of resilience in this population. We aimed to clarify current concepts of resilience in the field, elucidate gaps in the literature, and provide recommendations for future research. A total of 20 articles published between 2014 and 2015 were included. Six studies were neuroimaging studies, while the remaining studies used various psychological assessments. Most studies were cross-sectional except for three studies with naturalistic follow-up, one single-blind randomized controlled trial, and two published protocols of prospective studies. The following patterns of research were evident among the highly heterogeneous literature: studies focusing on protective factors and others emphasizing dynamic processes, studies investigating 'at-risk but resilient' groups (e.g. nonpsychotic siblings of patients with schizophrenia), and studies using psychological scales to measure resilience. The heterogeneity in how reports conceptualize, assess, and interpret resilience likely reflects the multidimensional nature of the concept itself and the lack of a 'gold standard' in assessing resilience in schizophrenia. Further research is needed to make recommendations on how to facilitate resilience in clinical care.
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Resilient Control Systems Practical Metrics Basis for Defining Mission Impact
Energy Technology Data Exchange (ETDEWEB)
Craig G. Rieger
2014-08-01
"Resilience” describes how systems operate at an acceptable level of normalcy despite disturbances or threats. In this paper we first consider the cognitive, cyber-physical interdependencies inherent in critical infrastructure systems and how resilience differs from reliability to mitigate these risks. Terminology and metrics basis are provided to integrate the cognitive, cyber-physical aspects that should be considered when defining solutions for resilience. A practical approach is taken to roll this metrics basis up to system integrity and business case metrics that establish “proper operation” and “impact.” A notional chemical processing plant is the use case for demonstrating how the system integrity metrics can be applied to establish performance, and
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Directory of Open Access Journals (Sweden)
Linliang Guo
2017-04-01
Full Text Available To satisfy the validation requirements of flight control law for advanced aircraft, a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel. A 3-degree-of-freedom gimbal, ventrally installed in the model, was used in conjunction with an actively controlled dynamically similar model of aircraft, which was equipped with the inertial measurement unit, attitude and heading reference system, embedded computer and servo-actuators. The model, which could be rotated around its center of gravity freely by the aerodynamic moments, together with the flow field, operator and real time control system made up the closed-loop testing circuit. The model is statically unstable in longitudinal direction, and it can fly stably in wind tunnel with the function of control augmentation of the flight control laws. The experimental results indicate that the model responds well to the operator’s instructions. The response of the model in the tests shows reasonable agreement with the simulation results. The difference of response of angle of attack is less than 0.5°. The effect of stability augmentation and attitude control law was validated in the test, meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.
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Framing resilience: social uncertainty in designing urban climate resilience
Wardekker, J.A.
2016-01-01
Building urban resilience to climate change and other challenges will be essential for maintaining thriving cities into the future. Resilience has become very popular in both research on and practice of climate adaptation. However, people have different interpretations of what it means: what resilience-building contributes to, what the problems, causes and solutions are, and what trade-offs, side-effects and other normative choices are acceptable. These different ways of ‘framing’ climate res...
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Hydraulic actuator mechanism to control aircraft spoiler movements through dual input commands
Irick, S. C. (Inventor)
1981-01-01
An aircraft flight spoiler control mechanism is described. The invention enables the conventional, primary spoiler control system to retain its operational characteristics while accommodating a secondary input controlled by a conventional computer system to supplement the settings made by the primary input. This is achieved by interposing springs between the primary input and the spoiler control unit. The springs are selected to have a stiffness intermediate to the greater force applied by the primary control linkage and the lesser resistance offered by the spoiler control unit. Thus, operation of the primary input causes the control unit to yield before the springs, yet, operation of the secondary input, acting directly on the control unit, causes the springs to yield and absorb adjustments before they are transmitted into the primary control system.
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MD-11 PCA - Closeup view of aircraft on ramp
1995-01-01
This McDonnell Douglas MD-11 has taxied to a position on the flightline at NASA's Dryden Flight Research Center, Edwards, California, following its completion of the first and second landings ever performed by a transport aircraft under engine power only (on Aug. 29, 1995). The milestone flight, with NASA research pilot and former astronaut Gordon Fullerton at the controls, was part of a NASA project to develop a computer-assisted engine control system that enables a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft (PCA) system uses standard autopilot controls already present in the cockpit, together with the new programming in the aircraft's flight control computers. The PCA concept is simple. For pitch control, the program increases thrust to climb and reduces thrust to descend. To turn right, the autopilot increases the left engine thrust while decreasing the right engine thrust. The initial Propulsion-Controlled Aircraft studies by NASA were carried out at Dryden with a modified twin-engine F-15 research aircraft.
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Guest, Rebecca; Craig, Ashley; Nicholson Perry, Kathryn; Tran, Yvonne; Ephraums, Catherine; Hales, Alison; Dezarnaulds, Annalisa; Crino, Rocco; Middleton, James
2015-11-01
To examine change in resilience in people with spinal cord injury (SCI) when group cognitive behavior therapy (GCBT) was added to routine psychosocial rehabilitation (RPR). A prospective repeated-measures cohort design was used to determine the efficacy of the addition of GCBT (n = 50). The control group consisted of individuals receiving RPR, which included access to individual CBT (ICBT) when required (n = 38). Groups were assessed on 3 occasions: soon after admission, within 2 weeks of discharge, and 6-months postdischarge. Measures included sociodemographic, injury, and psychosocial factors. The outcome variable was resilience, considered an important outcome measure for recovery. To adjust for baseline differences in self-efficacy, depressive mood and anxiety between the 2 groups, these factors were entered into a repeated measures multivariate analysis of covariance (MANCOVA) as covariates. Latent class analysis was used to determine the best-fitting model of resilience trajectories for both groups. The MANCOVA indicated that the addition of GCBT to psychosocial rehabilitation did not result in improved resilience compared with the ICBT group. Trajectory data indicated over 60% were demonstrating acceptable resilience irrespective of group. Changes in resilience mean scores suggest the addition of GCBT adds little to resilience outcomes. Latent class modeling indicated both groups experienced similar trajectories of improvement and deterioration. Results highlight the importance of conducting multivariate modeling analysis that isolates subgroups of related cases over time to understand complex trajectories. Further research is needed to clarify individual differences in CBT intervention preference as well as other factors which impact on resilience. (c) 2015 APA, all rights reserved).
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Lee, Seung Min; Sung, Kyung Mi
2017-06-01
The purpose of this study was to examine the effects of a violence coping program (VCP) based on Polk's middle-range theory of resilience on nursing competency, resilience, burnout, and the ability to cope with violence in nurses working in emergency rooms. A quasi-experimental study, with a nonequivalent control group and a pretest-posttest design, was conducted. Participants were 36 nurses who worked in emergency rooms and had experienced violence; 18 nurses from D hospital and 18 nurses from C hospital were assigned to the experimental and control groups, respectively. The experimental group received the VCP twice per week for 8 weeks. Levels of resilience, F=59.41, pnursing competency, F=59.41 pburnout, F=52.74, pburnout and improving resilience, active coping behavior, and nursing competency. Therefore, it would be a useful intervention for improving the quality of nursing care provided in emergency rooms. © 2017 Korean Society of Nursing Science
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Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future Directions
Cox, David E.; Cunningham, Kevin; Jordan, Thomas L.
2012-01-01
Subscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research facility to address this type of flight-testing. Over the last several years (2009-2011) it has been used to perform 58 research flights with an unmanned, remotely-piloted, dynamically-scaled airplane. This paper will present an overview of the facility and its architecture and summarize the experimental data collected. All flights to date have been conducted within visual range of a safety observer. Current plans for the facility include expanding the test volume to altitudes and distances well beyond visual range. The architecture and instrumentation changes associated with this upgrade will also be presented.
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Directory of Open Access Journals (Sweden)
David Eisenman
2014-08-01
Full Text Available Public health officials need evidence-based methods for improving community disaster resilience and strategies for measuring results. This methods paper describes how one public health department is addressing this problem. This paper provides a detailed description of the theoretical rationale, intervention design and novel evaluation of the Los Angeles County Community Disaster Resilience Project (LACCDR, a public health program for increasing community disaster resilience. The LACCDR Project utilizes a pretest–posttest method with control group design. Sixteen communities in Los Angeles County were selected and randomly assigned to the experimental community resilience group or the comparison group. Community coalitions in the experimental group receive training from a public health nurse trained in community resilience in a toolkit developed for the project. The toolkit is grounded in theory and uses multiple components to address education, community engagement, community and individual self-sufficiency, and partnerships among community organizations and governmental agencies. The comparison communities receive training in traditional disaster preparedness topics of disaster supplies and emergency communication plans. Outcome indicators include longitudinal changes in inter-organizational linkages among community organizations, community member responses in table-top exercises, and changes in household level community resilience behaviors and attitudes. The LACCDR Project is a significant opportunity and effort to operationalize and meaningfully measure factors and strategies to increase community resilience. This paper is intended to provide public health and academic researchers with new tools to conduct their community resilience programs and evaluation research. Results are not yet available and will be presented in future reports.
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Children's negative emotions and ego-resiliency: longitudinal relations with social competence.
Taylor, Zoe E; Eisenberg, Nancy; VanSchyndel, Sarah K; Eggum-Wilkens, Natalie D; Spinrad, Tracy L
2014-04-01
We examined the relations of negative emotions in toddlerhood to the development of ego-resiliency and social competence across early childhood. Specifically, we addressed whether fear and anger/frustration in 30-month-old children (N = 213) was associated with the development of ego-resiliency across 4 time points (42 to 84 months), and, in turn, whether ego-resiliency predicted social competence at 84 months. Child anger/frustration negatively predicted the intercept of ego-resiliency at 42 months (controlling for prior ego-resiliency at 18 months) as well as the slope. Fear did not significantly predict either the intercept or slope of ego-resiliency in the structural model, although it was positively correlated with anger/frustration and was negatively related to ego-resiliency in zero-order correlations. The slope of ego-resiliency was positively related to children's social competence at 84 months; however, the intercept of ego-resiliency (set at 42 months) was not a significant predictor of later social competence. Furthermore, the slope of ego-resiliency mediated the relations between anger/frustration and children's later social competence. The results suggest that individual differences in anger/frustration might contribute to the development of ego-resiliency, which, in turn, is associated with children's social competence.
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El Houda Thabet, Rihab; Combastel, Christophe; Raïssi, Tarek; Zolghadri, Ali
2015-09-01
The paper develops a set membership detection methodology which is applied to the detection of abnormal positions of aircraft control surfaces. Robust and early detection of such abnormal positions is an important issue for early system reconfiguration and overall optimisation of aircraft design. In order to improve fault sensitivity while ensuring a high level of robustness, the method combines a data-driven characterisation of noise and a model-driven approach based on interval prediction. The efficiency of the proposed methodology is illustrated through simulation results obtained based on data recorded in several flight scenarios of a highly representative aircraft benchmark.
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Directory of Open Access Journals (Sweden)
L Ebersöhn
2012-01-01
Full Text Available In this article we describe how using a visual, child-friendly measure of resilience in a randomised control trial (RCT, the Kgolo Mmogo (KM project, resulted in representative insights on resilience in a mother-child relationship where the mother is HIV-positive. We used the existing psychological method Kinetic Family Drawing (KFD to measure resilience of young children in the qualitative phase of the concurrent mixed method RCT as the children represent cultural groups for whom standardized measures have not been developed. We use the case example of baseline KM assessment data of 6 year olds (n = 11; 3 female, 8 male. The results of the study demonstrate that the visual and qualitative data from children (KFD added to quantitative information obtained from mothers (Vineland Adaptive Behavior Scale, VABS. Additional information from the KFD had interpretation value for VABS scores and provided a child's perspective regarding resilience. Contrasting information from the KFD problematized mothers' perspectives as indicated in the VABS. The absence of significant information in KFD results regarding VABS sub-domains indicates differences in the cultural/contextual conceptualization of resilience. This exploratory study indicates initial support for the cross-cultural utility of the KFD to measure resilience in young children faced with adversity.
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Omidvar, Mohsen; Mazloumi, Adel; Mohammad Fam, Iraj; Nirumand, Fereshteh
2017-01-01
Resilience engineering (RE) can be an alternative technique to the traditional risk assessment and management techniques, to predict and manage safety conditions of modern socio-technical organizations. While traditional risk management approaches are retrospective and highlight error calculation and computation of malfunction possibilities, resilience engineering seeks ways to improve capacity at all levels of organizations in order to build strong yet flexible processes. Considering the resilience potential measurement as a concern in complex working systems, the aim of this study was to quantify the resilience by the help of fuzzy sets and Multi-Criteria Decision-Making (MCDM) techniques. In this paper, we adopted the fuzzy analytic hierarchy process (FAHP) method to measure resilience in a gas refinery plant. A resilience assessment framework containing six indicators, each with its own sub-indicators, was constructed. Then, the fuzzy weights of the indicators and the sub-indicators were derived from pair-wise comparisons conducted by experts. The fuzzy evaluating vectors of the indicators and the sub-indicators computed according to the initial assessment data. Finally, the Comprehensive Resilience Index (CoRI), Resilience Grade (RG), and Resilience Early Warning Grade (REWG) were established. To demonstrate the applicability of the proposed method, an illustrative example in a gas refinery complex (an instance of socio-technical systems) was provided. CoRI of the refinery ranked as "III". In addition, for the six main indicators, RG and REWG ranked as "III" and "NEWZ", respectively, except for C3, in which RG ranked as "II", and REWG ranked as "OEWZ". The results revealed the engineering practicability and usefulness of the proposed method in resilience evaluation of socio-technical systems.
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Flood Resilient Systems and their Application for Flood Resilient Planning
Manojlovic, N.; Gabalda, V.; Antanaskovic, D.; Gershovich, I.; Pasche, E.
2012-04-01
Following the paradigm shift in flood management from traditional to more integrated approaches, and considering the uncertainties of future development due to drivers such as climate change, one of the main emerging tasks of flood managers becomes the development of (flood) resilient cities. It can be achieved by application of non-structural - flood resilience measures, summarised in the 4As: assistance, alleviation, awareness and avoidance (FIAC, 2007). As a part of this strategy, the key aspect of development of resilient cities - resilient built environment can be reached by efficient application of Flood Resilience Technology (FReT) and its meaningful combination into flood resilient systems (FRS). FRS are given as [an interconnecting network of FReT which facilitates resilience (including both restorative and adaptive capacity) to flooding, addressing physical and social systems and considering different flood typologies] (SMARTeST, http://www.floodresilience.eu/). Applying the system approach (e.g. Zevenbergen, 2008), FRS can be developed at different scales from the building to the city level. Still, a matter of research is a method to define and systematise different FRS crossing those scales. Further, the decision on which resilient system is to be applied for the given conditions and given scale is a complex task, calling for utilisation of decision support tools. This process of decision-making should follow the steps of flood risk assessment (1) and development of a flood resilience plan (2) (Manojlovic et al, 2009). The key problem in (2) is how to match the input parameters that describe physical&social system and flood typology to the appropriate flood resilient system. Additionally, an open issue is how to integrate the advances in FReT and findings on its efficiency into decision support tools. This paper presents a way to define, systematise and make decisions on FRS at different scales of an urban system developed within the 7th FP Project
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Declining resilience of ecosystem functions under biodiversity loss.
Oliver, Tom H; Isaac, Nick J B; August, Tom A; Woodcock, Ben A; Roy, David B; Bullock, James M
2015-12-08
The composition of species communities is changing rapidly through drivers such as habitat loss and climate change, with potentially serious consequences for the resilience of ecosystem functions on which humans depend. To assess such changes in resilience, we analyse trends in the frequency of species in Great Britain that provide key ecosystem functions--specifically decomposition, carbon sequestration, pollination, pest control and cultural values. For 4,424 species over four decades, there have been significant net declines among animal species that provide pollination, pest control and cultural values. Groups providing decomposition and carbon sequestration remain relatively stable, as fewer species are in decline and these are offset by large numbers of new arrivals into Great Britain. While there is general concern about degradation of a wide range of ecosystem functions, our results suggest actions should focus on particular functions for which there is evidence of substantial erosion of their resilience.
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Thermal comfort assessment in civil aircraft cabins
Pang Liping; Qin Yue; Liu Dong; Liu Meng
2014-01-01
Aircraft passengers are more and demanding in terms of thermal comfort. But it is not yet easy for aircraft crew to control the environment control system (ECS) that satisfies the thermal comfort for most passengers due to a number of causes. This paper adopts a corrected predicted mean vote (PMV) model and an adaptive model to assess the thermal comfort conditions for 31 investigated flights and draws the conclusion that there does exist an uncomfortable thermal phenomenon in civil aircraft ...
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Resilience Indicator Summaries and Resilience Scores CNMI JPEG Maps
National Oceanic and Atmospheric Administration, Department of Commerce — Maps of relative classifications (low to high) for six resilience indicators and two anthropogenic stressors and a map of final relative resilience scores for 78...
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Resilience Indicator Summaries and Resilience Scores CNMI Excel database
National Oceanic and Atmospheric Administration, Department of Commerce — Maps of relative classifications (low to high) for six resilience indicators and two anthropogenic stressors and a map of final relative resilience scores for 78...
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A Measure of Team Resilience: Developing the Resilience at Work Team Scale.
McEwen, Kathryn; Boyd, Carolyn M
2018-03-01
This study develops, and initial evaluates, a new measure of team-based resilience for use in research and practice. We conducted preliminary analyses, based on a cross-sectional sample of 344 employees nested within 31 teams. Seven dimensions were identified through exploratory and confirmatory factor analyses. The measure had high reliability and significant discrimination to indicate the presence of a unique team-based aspect of resilience that contributed to higher work engagement and higher self-rated team performance, over and above the effects of individual resilience. Multilevel analyses showed that team, but not individual, resilience predicted self-rated team performance. Practice implications include a need to focus on collective as well as individual behaviors in resilience-building. The measure provides a diagnostic instrument for teams and a scale to evaluate organizational interventions and research the relationship of resilience to other constructs.
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A Theory on Urban Resilience to Floods - A Basis for Alternative Planning Practices
Directory of Open Access Journals (Sweden)
Kuei-Hsien Liao
2012-12-01
Full Text Available River cities require a management approach based on resilience to floods rather than on resistance. Resisting floods by means of levees, dams, and channelization neglects inherent uncertainties arising from human-nature couplings and fails to address the extreme events that are expected to increase with climate change, and is thereby not a reliable approach to long-term flood safety. By applying resilience theory to address system persistence through changes, I develop a theory on "urban resilience to floods" as an alternative framework for urban flood hazard management. Urban resilience to floods is defined as a city's capacity to tolerate flooding and to reorganize should physical damage and socioeconomic disruption occur, so as to prevent deaths and injuries and maintain current socioeconomic identity. It derives from living with periodic floods as learning opportunities to prepare the city for extreme ones. The theory of urban resilience to floods challenges the conventional wisdom that cities cannot live without flood control, which in effect erodes resilience. To operationalize the theory for planning practice, a surrogate measure - the percent floodable area - is developed for assessing urban resilience to floods. To enable natural floodplain functions to build urban resilience to floods, flood adaptation is advocated in order to replace flood control for mitigating flood hazards.
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A novel control technique for active shunt power filters for aircraft applications
Lavopa, Elisabetta
2011-01-01
The More Electric Aircraft is a technological trend in modern aerospace industry to increasingly use electrical power on board the aircraft in place of mechanical, hydraulic and pneumatic power to drive aircraft subsystems. This brings major changes to the aircraft electrical system, increasing the complexity of the network topology together with stability and power quality issues. Shunt active power filters are a viable solution for power quality enhancement, in order to comply with the stan...
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Essentials of aircraft armaments
Kaushik, Mrinal
2017-01-01
This book aims to provide a complete exposure about armaments from their design to launch from the combat aircraft. The book details modern ammunition and their tactical roles in warfare. The proposed book discusses aerodynamics, propulsion, structural as well as navigation, control, and guidance of aircraft armament. It also introduces the various types of ammunition developed by different countries and their changing trends. The book imparts knowledge in the field of design, and development of aircraft armaments to aerospace engineers and covers the role of the United Nations in peacekeeping and disarmament. The book will be very useful to researchers, students, and professionals working in design and manufacturing of aircraft armaments. The book will also serve air force and naval aspirants, and those interested in working on defence research and developments organizations. .
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Johnston, Marjorie C; Porteous, Terry; Crilly, Michael A; Burton, Christopher D; Elliott, Alison; Iversen, Lisa; McArdle, Karen; Murray, Alison; Phillips, Louise H; Black, Corri
2015-01-01
Findings from physical disease resilience research may be used to develop approaches to reduce the burden of disease. However, there is no consensus on the definition and measurement of resilience in the context of physical disease. The aim was to summarize the range of definitions of physical disease resilience and the approaches taken to study it in studies examining physical disease and its relationship to resilient outcomes. Electronic databases were searched from inception to March 2013 for studies in which physical disease was assessed for its association with resilient outcomes. Article screening, data extraction, and quality assessment were carried out independently by 2 reviewers, with disagreements being resolved by a third reviewer. The results were combined using a narrative technique. Of 2280 articles, 12 met the inclusion criteria. Of these studies, 1 was of high quality, 9 were of moderate quality, and 2 were low quality. The common findings were that resilience involves maintaining healthy levels of functioning following adversity and that it is a dynamic process not a personality trait. Studies either assessed resilience based on observed outcomes or via resilience measurement scales. They either considered physical disease as an adversity leading to resilience or as a variable modifying the relationship between adversity and resilience. This work begins building consensus as to the approach to take when defining and measuring physical disease resilience. Resilience should be considered as a dynamic process that varies across the life-course and across different domains, therefore the choice of a resilience measure should reflect this. Copyright © 2015 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.
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Directory of Open Access Journals (Sweden)
Motlalepule Ruth Mampane
2014-11-01
Full Text Available Factors that contribute to resilience are key to the positive development of youths, and knowledge of such factors is essential for promoting resilience in schools through both policy and practice. This study reports on the results of an item and factor analysis of the Resilience Questionnaire for Middle-adolescents in Township Schools (R-MATS that was used to survey 291 Grade 9 middle-adolescent learners from two black-only township secondary schools. The majority of respondents indicated an overall sense of contending with various stressors, especially the exposure to violence, and academic challenges. Respondents attributed their buoyancy to individual and environmental factors, such as self-confidence, an internal locus of control, a tough personality, commitment, being achievement-oriented, as well as positive identification of and access to social support.
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DEFF Research Database (Denmark)
Carruth, Susan
2015-01-01
by planners when aiming to construct resilient energy plans. It concludes that a graphical language has the potential to be a significant tool, flexibly facilitating cross-disciplinary communication and decision-making, while emphasising that its role is to support imaginative, resilient planning rather than...... the relationship between resilience and energy planning, suggesting that planning in, and with, time is a core necessity in this domain. It then reviews four examples of graphically mapping with time, highlighting some of the key challenges, before tentatively proposing a graphical language to be employed...
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The Effect of Faster Engine Response on the Lateral Directional Control of a Damaged Aircraft
May, Ryan D.; Lemon, Kimberly A.; Csank, Jeffrey T.; Litt, Jonathan S.; Guo, Ten-Huei
2012-01-01
The integration of flight control and propulsion control has been a much discussed topic, especially for emergencies where the engines may be able to help stabilize and safely land a damaged aircraft. Previous research has shown that for the engines to be effective as flight control actuators, the response time to throttle commands must be improved. Other work has developed control modes that accept a higher risk of engine failure in exchange for improved engine response during an emergency. In this effort, a nonlinear engine model (the Commercial Modular Aero-Propulsion System Simulation 40k) has been integrated with a nonlinear airframe model (the Generic Transport Model) in order to evaluate the use of enhanced-response engines as alternative yaw rate control effectors. Tests of disturbance rejection and command tracking were used to determine the impact of the engines on the aircraft's dynamical behavior. Three engine control enhancements that improve the response time of the engine were implemented and tested in the integrated simulation. The enhancements were shown to increase the engine s effectiveness as a yaw rate control effector when used in an automatic feedback loop. The improvement is highly dependent upon flight condition; the airframe behavior is markedly improved at low altitude, low speed conditions, and relatively unchanged at high altitude, high speed.
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Resilience among abused and neglected children grown up.
McGloin, J M; Widom, C S
2001-01-01
Although an extensive literature has accumulated documenting the maladaptive outcomes associated with childhood victimization, a limited body of knowledge addresses resilience. This paper sought to operationalize the construct of resilience across a number of domains of functioning and time periods and to determine the extent to which abused and neglected children grown up demonstrate resilience. Substantiated cases of child abuse and neglect from 1967 to 1971 were matched on gender, age, race, and approximate family social class with nonabused and nonneglected children and followed prospectively into young adulthood. Between 1989 and 1995. 1,196 participants (676 abused and neglected and 520 controls) were administered a 2-hr in-person interview, including a psychiatric assessment. Resilience requires meeting the criteria for success across six of eight domains of functioning: employment, homelessness, education, social activity, psychiatric disorder, substance abuse, and two domains assessing criminal behavior (official arrest and self-reports of violence). Results indicate that 22% of abused and neglected individuals meet the criteria for resilience. More females met the criteria for resilience and females were successful across a greater number of domains than males. We speculate on the meaning of these findings and discuss implications for the child maltreatment field. Limitations of the study are also acknowledged.
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NASA/RAE collaboration on nonlinear control using the F-8C digital fly-by-wire aircraft
Butler, G. F.; Corbin, M. J.; Mepham, S.; Stewart, J. F.; Larson, R. R.
1983-01-01
Design procedures are reviewed for variable integral control to optimize response (VICTOR) algorithms and results of preliminary flight tests are presented. The F-8C aircraft is operated in the remotely augmented vehicle (RAV) mode, with the control laws implemented as FORTRAN programs on a ground-based computer. Pilot commands and sensor information are telemetered to the ground, where the data are processed to form surface commands which are then telemetered back to the aircraft. The RAV mode represents a singlestring (simplex) system and is therefore vulnerable to a hardover since comparison monitoring is not possible. Hence, extensive error checking is conducted on both the ground and airborne computers to prevent the development of potentially hazardous situations. Experience with the RAV monitoring and validation procedures is described.
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1999-03-01
This report documents an investigation of the flight paths of 13 selected controlled flight into terrain (CFIT) aircraft accidents that occurred between 1985 and 1997. The Operations Assessment Division (DTS-43) and the Aviation Safety Division (DTS-...
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Shen, H; Xu, Y; Dickinson, B T
2014-11-18
Inspired by sensing strategies observed in birds and bats, a new attitude control concept of directly using real-time pressure and shear stresses has recently been studied. It was shown that with an array of onboard airflow sensors, small unmanned aircraft systems can promptly respond to airflow changes and improve flight performances. In this paper, a mapping function is proposed to compute aerodynamic moments from the real-time pressure and shear data in a practical and computationally tractable formulation. Since many microscale airflow sensors are embedded on the small unmanned aircraft system surface, it is highly possible that certain sensors may fail. Here, an adaptive control system is developed that is robust to sensor failure as well as other numerical mismatches in calculating real-time aerodynamic moments. The advantages of the proposed method are shown in the following simulation cases: (i) feedback pressure and wall shear data from a distributed array of 45 airflow sensors; (ii) 50% failure of the symmetrically distributed airflow sensor array; and (iii) failure of all the airflow sensors on one wing. It is shown that even if 50% of the airflow sensors have failures, the aircraft is still stable and able to track the attitude commands.
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Design of LPV-Based Sliding Mode Controller with Finite Time Convergence for a Morphing Aircraft
Directory of Open Access Journals (Sweden)
Nuan Wen
2017-01-01
Full Text Available This paper proposes a finite time convergence sliding mode control (FSMC strategy based on linear parameter-varying (LPV methodology for the stability control of a morphing aircraft subject to parameter uncertainties and external disturbances. Based on the Kane method, a longitudinal dynamic model of the morphing aircraft is built. Furthermore, the linearized LPV model of the aircraft in the wing transition process is obtained, whose scheduling parameters are wing sweep angle and wingspan. The FSMC scheme is developed into LPV systems by applying the previous results for linear time-invariant (LTI systems. The sufficient condition in form of linear matrix inequality (LMI constraints is derived for the existence of a reduced-order sliding mode, in which the dynamics can be ensured to keep robust stability and L2 gain performance. The tensor-product (TP model transformation approach can be directly applied to solve infinite LMIs belonging to the polynomial parameter-dependent LPV system. Then, by the parameter-dependent Lyapunov function stability analysis, the synthesized FSMC is proved to drive the LPV system trajectories toward the predefined switching surface with a finite time arrival. Comparative simulation results in the nonlinear model demonstrate the robustness and effectiveness of this approach.
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Teaching Resilience: A Narrative Inquiry into the Importance of Teacher Resilience
Vance, Angela; Pendergast, Donna; Garvis, Susanne
2015-01-01
This study set out to explore how high school teachers perceive their resilience as they teach a scripted social and emotional learning program to students with the goal of promoting the resilience skills of the students in their pastoral care classes. In this emerging field of research on teacher resilience, there is a paucity of research…
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Rights for resilience: food sovereignty, power, and resilience in development practice
Directory of Open Access Journals (Sweden)
Marygold Walsh-Dilley
2016-03-01
Full Text Available Even as resilience thinking becomes evermore popular as part of strategic programming among development and humanitarian organizations, uncertainty about how to define, operationalize, measure, and evaluate resilience for development goals prevails. As a result, many organizations and institutions have undertaken individual, collective, and simultaneous efforts toward clarification and definition. This has opened up a unique opportunity for a rethinking of development practices. The emergent consensus about what resilience means within development practice will have important consequences both for development practitioners and the communities in which they work. Incorporating resilience thinking into development practice has the potential to radically transform this arena in favor of social and environmental justice, but it could also flounder as a way to dress old ideas in new clothes or, at worst, to further exploit, disempower, and marginalize the world's most vulnerable populations. We seek to make an intervention into the definitional debates surrounding resilience that supports the former and helps prevent the latter. We argue that resilience thinking as it has been developed in social-ecological systems and allied literatures has a lot in common with the concept of food sovereignty and that paying attention to some of the lessons and claims of food sovereignty movements could contribute toward building a consensus around resilience that supports social and environmental justice. In particular, the food sovereignty movement relies on a strategy that elevates rights. We suggest that a rights-based approach to resilience-oriented development practice could contribute to its application in just and equitable ways.
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Howell, Charles T.; Jones, Frank; Hutchinson, Brian; Joyce, Claude; Nelson, Skip; Melum, Mike
2017-01-01
The NASA Langley Research Center has transformed a Cirrus Design SR22 general aviation (GA) aircraft into an Unmanned Aerial Systems (UAS) Surrogate research aircraft which has served for several years as a platform for unmanned systems research and development. The aircraft is manned with a Safety Pilot and a Research Systems Operator (RSO) that allows for flight operations almost any-where in the national airspace system (NAS) without the need for a Federal Aviation Administration (FAA) Certificate of Authorization (COA). The UAS Surrogate can be remotely controlled from a modular, transportable ground control station (GCS) like a true UAS. Ground control of the aircraft is accomplished by the use of data links that allow the two-way passage of the required data to control the aircraft and provide the GCS with situational awareness. The original UAS Surrogate data-link system was composed of redundant very high frequency (VHF) data radio modems with a maximum range of approximately 40 nautical miles. A new requirement was developed to extend this range beyond visual range (BVR). This new requirement led to the development of a satellite communications system that provided the means to command and control the UAS Surrogate at ranges beyond the limits of the VHF data links. The system makes use of the Globalstar low earth orbit (LEO) satellite communications system. This paper will provide details of the development, implementation, and flight testing of the satellite data communications system on the UAS Surrogate research aircraft.
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National Aeronautics and Space Administration — Control of extremely lightweight, long endurance aircraft poses a challenging aeroservoelastic (ASE) problem due to significantly increased flexibility, and...
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National Aeronautics and Space Administration — Control of extremely lightweight, long endurance aircraft poses a challenging aeroservoelastic (ASE) problem due to significantly increased flexibility, and...
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Resilience in disaster research
DEFF Research Database (Denmark)
Dahlberg, Rasmus; Johannessen-Henry, Christine Tind; Raju, Emmanuel
2015-01-01
This paper explores the concept of resilience in disaster management settings in modern society. The diversity and relatedness of ‘resilience’ as a concept and as a process are reflected in its presentation through three ‘versions’: (i) pastoral care and the role of the church for victims...... of disaster trauma, (ii) federal policy and the US Critical Infrastructure Plan, and (iii) the building of resilient communities for disaster risk reduction practices. The three versions aim to offer characteristic expressions of resilience, as increasingly evident in current disaster literature....... In presenting resilience through the lens of these three versions, the article highlights the complexity in using resilience as an all-encompassing word. The article also suggests the need for understanding the nexuses between risk, vulnerability, and policy for the future of resilience discourse....
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An overdue alignment of risk and resilience? A conceptual contribution to community resilience.
Mochizuki, Junko; Keating, Adriana; Liu, Wei; Hochrainer-Stigler, Stefan; Mechler, Reinhard
2018-04-01
A systematic review of literature on community resilience measurement published between 2005 and 2014 revealed that the profound lack of clarity on risk and resilience is one of the main reasons why confusion about terms such as adaptive capacity, resilience, and vulnerability persists, despite the effort spared to operationalise these concepts. Resilience is measured in isolation in some cases, where a shock is perceived to arise external to the system of interest. Problematically, this contradicts the way in which the climate change and disaster communities perceive risk as manifesting itself endogenously as a function of exposure, hazard, and vulnerability. The common conceptualisation of resilience as predominantly positive is problematic as well when, in reality, many undesirable properties of a system are resilient. Consequently, this paper presents an integrative framework that highlights the interactions between risk drivers and coping, adaptive, and transformative capacities, providing an improved conceptual basis for resilience measurement. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.
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NEW MODEL FOR QUANTIFICATION OF ICT DEPENDABLE ORGANIZATIONS RESILIENCE
Directory of Open Access Journals (Sweden)
Zora Arsovski
2011-03-01
Full Text Available Business environment today demands high reliable organizations in every segment to be competitive on the global market. Beside that, ICT sector is becoming irreplaceable in many fields of business, from the communication to the complex systems for process control and production. To fulfill those requirements and to develop further, many organizations worldwide are implementing business paradigm called - organizations resilience. Although resilience is well known term in many science fields, it is not well studied due to its complex nature. This paper is dealing with developing the new model for assessment and quantification of ICT dependable organizations resilience.
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Cross-cultural validation of the Resilience Scale for Adults (RSA) in Iran.
Jowkar, Bahram; Friborg, Oddgeir; Hjemdal, Odin
2010-10-01
Resilience, as an ability to withstand and rebound from crisis and adversity, is becoming an increasingly popular concept in research on intervention and prevention of mental health. The present study examined psychometric properties of a Persian version of the Resilience Scale for Adults (RSA), a scale intended to measure protective factors presumed to enhance resilience. The participants were 373 university undergraduate students, as well as 30 pairs of run-away girls and a matched control group. A confirmatory factor analysis verified the Norwegian five-factor structure. All subscale scores, personal competence, social competence, family cohesion, social resources and structured style, had good reliability. The convergent validity of the RSA was supported by showing positive associations with another resilience scale, i.e., a Persian version of the Connor-Davidson Resilience Scale (CD-RISC). Predictive validity of the RSA was supported, as well, by significantly differentiating between girls who had run away from home and a matched control group. The results indicate that the RSA may be a valid and reliable scale for the assessment of resilience protective resources in an Iranian population. © 2010 The Authors. Scandinavian Journal of Psychology © 2010 The Scandinavian Psychological Associations.
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Towards Quantifying Programmable Logic Controller Resilience Against Intentional Exploits
2012-03-22
may improve the SCADA system’s resilience against DoS and man-in-the-middle ( MITM ) attacks. DoS attacks may be mitigated by using the redundant...paths available on the network links. MITM attacks may be mitigated by the data integrity checks associated with the middleware. Figure 4 illustrates
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Robust Longitudinal Aircraft- Control Based on an Adaptive Fuzzy-Logic Algorithm
Directory of Open Access Journals (Sweden)
Abdel- Latif Elshafei
2002-06-01
Full Text Available To study the aircraft response to a fast pull-up manoeuvre, a short period approximation of the longitudinal model is considered. The model is highly nonlinear and includes parametric uncertainties. To cope with a wide range of command signals, a robust adaptive fuzzy logic controller is proposed. The proposed controller adopts a dynamic inversion approach. Since feedback linearization is practically imperfect, robustifying and adaptive components are included in the control law to compensate for modeling errors and achieve acceptable tracking errors. Two fuzzy systems are implemented. The first system models the nominal values of the system’s nonlinearity. The second system is an adaptive one that compensates for modeling errors. The derivation of the control law based on a dynamic game approach is given in detail. Stability of the closed-loop control system is also verified. Simulation results based on an F16-model illustrate a successful tracking performance of the proposed controller.
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GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS
Directory of Open Access Journals (Sweden)
Stanislav Vladimirovich Daletskiy
2017-01-01
Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.
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Hanson, Curt; Miller, Chris; Wall, John H.; VanZwieten, Tannen S.; Gilligan, Eric T.; Orr, Jeb S.
2015-01-01
An Adaptive Augmenting Control (AAC) algorithm for the Space Launch System (SLS) has been developed at the Marshall Space Flight Center (MSFC) as part of the launch vehicle's baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a potential manual steering mode were also investigated by giving the pilot trajectory deviation cues and pitch rate command authority, which is the subject of this paper. Two NASA research pilots flew a total of 25 constant pitch rate trajectories using a prototype manual steering mode with and without adaptive control, evaluating six different nominal and off-nominal test case scenarios. Pilot comments and PIO ratings were given following each trajectory and correlated with aircraft state data and internal controller signals post-flight.
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Bundick, W. T.
1985-01-01
The application of the Generalized Likelihood Ratio technique to the detection and identification of aircraft control element failures has been evaluated in a linear digital simulation of the longitudinal dynamics of a B-737 aircraft. Simulation results show that the technique has potential but that the effects of wind turbulence and Kalman filter model errors are problems which must be overcome.
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Directory of Open Access Journals (Sweden)
A.N. Madewell
2016-09-01
Full Text Available The data presented in this article are related to the article entitled “Assessing Resilience in Emerging Adulthood: The Resilience Scale (RS, Connor Davidson Resilience Scale (CD-RISC, and Scale of Protective Factors (SPF” (Madewell and Ponce-Garcia, 2016 [1]. The data were collected from a sample of 451 college students from three universities located in the Southwestern region of the United States: 374 from a large public university and 67 from two smaller regional universities. The data from the three universities did not significantly differ in terms of demographics. The data represent participant responses on six measurements to include the Resilience Scale-25 (RS-25, Resilience Scale-14 (RS-14, Connor Davidson Resilience Scale-25 (CD-RISC-25, Connor Davidson Resilience Scale-10 (CD-RISC-10, Scale of Protective Factors-24 (SPF-24, and the Life Stressor Checklist Revised (LSC-R. Keywords: Scale of Protective Factors, Resilience Scale, Connor–Davidson Resilience Scale, Emerging adulthood, Confirmatory factor analysis
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Multifractal resilience and viability
Tchiguirinskaia, I.; Schertzer, D. J. M.
2017-12-01
The term resilience has become extremely fashionable and there had been many attempts to provide operational definition and in fact metrics going beyond a set of more or less ad-hoc indicators. The viability theory (Aubin and Saint-Pierre, 2011) have been used to give a rather precise mathematical definition of resilience (Deffuant and Gilbert, 2011). However, it does not grasp the multiscale nature of resilience that is rather fundamental as particularly stressed by Folke et al (2010). In this communication, we first recall a preliminary attempt (Tchiguirinskaia et al., 2014) to define multifractal resilience with the help of the maximal probable singularity. Then we extend this multifractal approach to the capture basin of the viability, therefore the resilient basin. Aubin, J P, A. Bayen, and P Saint-Pierre (2011). Viability Theory. New Directions. Springer, Berlin,. Deffuant, G. and Gilbert, N. (eds) (2011) Viability and Resilience of Complex Systems. Springer Berlin.Folke, C., S R Carpenter, B Walker, M Sheffer, T Chapin, and J Rockstroem (2010). Resilience thinking: integrating re- silience, adaptability and transformability. Ecology and So- ciety, 14(4):20, Tchiguirinskaia,I., D. Schertzer, , A. Giangola-Murzyn and T. C. Hoang (2014). Multiscale resilience metrics to assess flood. Proceedings of ICCSA 2014, Normandie University, Le Havre, France -.
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Framing resilience: social uncertainty in designing urban climate resilience
Wardekker, J.A.
2016-01-01
Building urban resilience to climate change and other challenges will be essential for maintaining thriving cities into the future. Resilience has become very popular in both research on and practice of climate adaptation. However, people have different interpretations of what it means: what
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1977-01-01
The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.
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Khanlou, Nazilla; Wray, Ron
2014-01-01
A literature review of child and youth resilience with a focus on: definitions and factors of resilience; relationships between resilience, mental health and social outcomes; evidence for resilience promoting interventions; and implications for reducing health inequities. To conduct the review, the first two following steps were conducted iteratively and informed the third step: 1) Review of published peer-review literature since 2000; and 2) Review of grey literature; and 3) Quasi-realist synthesis of evidence. Evidence from three perspectives were examined: i) whether interventions can improve 'resilience' for vulnerable children and youth; ii) whether there is a differential effect among different populations; and, iii) whether there is evidence that resilience interventions 'close the gap' on health and social outcome measures. Definitions of resilience vary as do perspectives on it. We argue for a hybrid approach that recognizes the value of combining multiple theoretical perspectives, epistemologies (positivistic and constructivist/interpretive/critical) in studying resilience. Resilience is: a) a process (rather than a single event), b) a continuum (rather than a binary outcome), and c) likely a global concept with specific dimensions. Individual, family and social environmental factors influence resilience. A social determinants perspective on resilience and mental health is emphasized. Programs and interventions to promoting resilience should be complimentary to public health measures addressing the social determinants of health. A whole community approach to resilience is suggested as a step toward closing the public health policy gap. Local initiatives that stimulate a local transformation process are needed. Recognition of each child's or youth's intersections of gender, lifestage, family resources within the context of their identity markers fits with a localized approach to resilience promotion and, at the same time, requires recognition of the
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Assessing Resilience in Stressed Watersheds
Directory of Open Access Journals (Sweden)
Kristine T. Nemec
2014-03-01
Full Text Available Although several frameworks for assessing the resilience of social-ecological systems (SESs have been developed, some practitioners may not have sufficient time and information to conduct extensive resilience assessments. We have presented a simplified approach to resilience assessment that reviews the scientific, historical, and social literature to rate the resilience of an SES with respect to nine resilience properties: ecological variability, diversity, modularity, acknowledgement of slow variables, tight feedbacks, social capital, innovation, overlap in governance, and ecosystem services. We evaluated the effects of two large-scale projects, the construction of a major dam and the implementation of an ecosystem recovery program, on the resilience of the central Platte River SES (Nebraska, United States. We used this case study to identify the strengths and weaknesses of applying a simplified approach to resilience assessment. Although social resilience has increased steadily since the predam period for the central Platte River SES, ecological resilience was greatly reduced in the postdam period as compared to the predam and ecosystem recovery program time periods.
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Family Resilience in the Military
Meadows, Sarah O.; Beckett, Megan K.; Bowling, Kirby; Golinelli, Daniela; Fisher, Michael P.; Martin, Laurie T.; Meredith, Lisa S.; Osilla, Karen Chan
2016-01-01
Abstract Military life presents a variety of challenges to military families, including frequent separations and relocations as well as the risks that service members face during deployment; however, many families successfully navigate these challenges. Despite a recent emphasis on family resilience, the U.S. Department of Defense (DoD) does not have a standard and universally accepted definition of family resilience. A standard definition is a necessary for DoD to more effectively assess its efforts to sustain and improve family resilience. RAND authors reviewed the literature on family resilience and, in this study, recommend a definition that could be used DoD-wide. The authors also reviewed DoD policies related to family resilience, reviewed models that describe family resilience and identified key family resilience factors, and developed several recommendations for how family-resilience programs and policies could be managed across DoD. PMID:28083409
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DEFF Research Database (Denmark)
Kamyod, Chayapol; Nielsen, Rasmus Hjorth; Prasad, Neeli R.
2014-01-01
The paper focuses on end-to-end resilience analysis of the IMS based network through the principal resilience parameters by using OPNET. The resilience behaviours of communication across multiple IMS domains are investigated at different communication scenarios and compared with previous state......-of-the-art. Moreover, the resilience effects when adding a redundancy of the S-CSCF unit are examined. The results disclose interesting resilience behaviours for long distance communications....
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Active Structural Acoustic Control in an Original A400M Aircraft Structure
International Nuclear Information System (INIS)
Koehne, C; Sachau, D; Renger, K
2016-01-01
Low frequency noise has always been a challenge in propeller driven aircraft. At low frequencies passive noise treatments are not as efficient as active noise reduction systems. The Helmut-Schmidt-University has built up a full-scale test rig with an original A400M aircraft structure. This provides a good opportunity to develop and test active noise reduction systems in a realistic environment. The currently installed system consists of mechanical actuators and acoustical sensors. The actuators are called TVAs (Tuneable Vibration Absorber) and contain two spring-mass systems whose natural frequencies are adjusted to the BPFs (Blade Passage Frequency) of the propellers. The TVAs are mounted to the frames and the force direction is normal to the skin. The sensors are condenser microphones which are attached to the primary structure of the airframe. The TVAs are equipped with signal processing devices. These components carry out Fourier transforms and signal amplification for the sensor data and actuator signals. The communication between the TVAs and the central control unit is implemented by the CAN Bus protocol and mainly consists of complex coefficients for the sensor and actuator data. This paper describes the basic structure of the system, the hardware set-up and function tests of the controller. (paper)
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Active Structural Acoustic Control in an Original A400M Aircraft Structure
Koehne, C.; Sachau, D.; Renger, K.
2016-09-01
Low frequency noise has always been a challenge in propeller driven aircraft. At low frequencies passive noise treatments are not as efficient as active noise reduction systems. The Helmut-Schmidt-University has built up a full-scale test rig with an original A400M aircraft structure. This provides a good opportunity to develop and test active noise reduction systems in a realistic environment. The currently installed system consists of mechanical actuators and acoustical sensors. The actuators are called TVAs (Tuneable Vibration Absorber) and contain two spring-mass systems whose natural frequencies are adjusted to the BPFs (Blade Passage Frequency) of the propellers. The TVAs are mounted to the frames and the force direction is normal to the skin. The sensors are condenser microphones which are attached to the primary structure of the airframe. The TVAs are equipped with signal processing devices. These components carry out Fourier transforms and signal amplification for the sensor data and actuator signals. The communication between the TVAs and the central control unit is implemented by the CAN Bus protocol and mainly consists of complex coefficients for the sensor and actuator data. This paper describes the basic structure of the system, the hardware set-up and function tests of the controller.
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Hicks, John W.; Moulton, Bryan J.
1988-01-01
The camber control loop of the X-29A FSW aircraft was designed to furnish the optimum L/D for trimmed, stabilized flight. A marked difference was noted between automatic wing camber control loop behavior in dynamic maneuvers and in stabilized flight conditions, which in turn affected subsonic aerodynamic performance. The degree of drag level increase was a direct function of maneuver rate. Attention is given to the aircraft flight drag polar effects of maneuver dynamics in light of wing camber control loop schedule. The effect of changing camber scheduling to better track the optimum automatic camber control L/D schedule is discussed.
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Application and Simulation of Fuzzy Neural Network PID Controller in the Aircraft Cabin Temperature
Directory of Open Access Journals (Sweden)
Ding Fang
2013-06-01
Full Text Available Considering complex factors of affecting ambient temperature in Aircraft cabin, and some shortages of traditional PID control like the parameters difficult to be tuned and control ineffective, this paper puts forward the intelligent PID algorithm that makes fuzzy logic method and neural network together, scheming out the fuzzy neural net PID controller. After the correction of the fuzzy inference and dynamic learning of neural network, PID parameters of the controller get the optimal parameters. MATLAB simulation results of the cabin temperature control model show that the performance of the fuzzy neural network PID controller has been greatly improved, with faster response, smaller overshoot and better adaptability.
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Aircraft dual-shaft jet engine with indirect action fuel flow controller
Tudosie, Alexandru-Nicolae
2017-06-01
The paper deals with an aircraft single-jet engine's control system, based on a fuel flow controller. Considering the engine as controlled object and its thrust the most important operation effect, from the multitude of engine's parameters only its rotational speed n is measurable and proportional to its thrust, so engine's speed has become the most important controlled parameter. Engine's control system is based on fuel injection Qi dosage, while the output is engine's speed n. Based on embedded system's main parts' mathematical models, the author has described the system by its block diagram with transfer functions; furthermore, some Simulink-Matlab simulations are performed, concerning embedded system quality (its output parameters time behavior) and, meanwhile, some conclusions concerning engine's parameters mutual influences are revealed. Quantitative determinations are based on author's previous research results and contributions, as well as on existing models (taken from technical literature). The method can be extended for any multi-spool engine, single- or twin-jet.
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Application of modern control design methodology to oblique wing research aircraft
Vincent, James H.
1991-01-01
A Linear Quadratic Regulator synthesis technique was used to design an explicit model following control system for the Oblique Wing Research Aircraft (OWRA). The forward path model (Maneuver Command Generator) was designed to incorporate the desired flying qualities and response decoupling. The LQR synthesis was based on the use of generalized controls, and it was structured to provide a proportional/integral error regulator with feedforward compensation. An unexpected consequence of this design approach was the ability to decouple the control synthesis into separate longitudinal and lateral directional designs. Longitudinal and lateral directional control laws were generated for each of the nine design flight conditions, and gain scheduling requirements were addressed. A fully coupled 6 degree of freedom open loop model of the OWRA along with the longitudinal and lateral directional control laws was used to assess the closed loop performance of the design. Evaluations were performed for each of the nine design flight conditions.
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McCann, Terence V; Songprakun, Wallapa; Stephenson, John
2017-08-01
The growing incidence of depression in developing countries, such as Thailand, is placing increasing pressure on public mental health services, and those living in rural areas have limited access to these services. Resilience is integral to the recovery of people with depression and to caregivers. This parallel-group randomised controlled trial evaluated the effectiveness of a guided self-help manual in improving resilience in adults diagnosed with moderate depression and their primary caregivers in Thailand. Our findings provide preliminary evidence that the approach is an effective way of increasing resilience in adults with depression and their caregivers.
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Resilience: Building immunity in psychiatry
Shastri, Priyvadan Chandrakant
2013-01-01
The challenges in our personal, professional, financial, and emotional world are on rise, more so in developing countries and people will be longing for mental wellness for achieving complete health in their life. Resilience stands for one's capacity to recover from extremes of trauma and stress. Resilience in a person reflects a dynamic union of factors that encourages positive adaptation despite exposure to adverse life experiences. One needs to have a three-dimensional construct for understanding resilience as a state (what is it and how does one identify it?), a condition (what can be done about it?), and a practice (how does one get there?). Evaluating the level of resilience requires the measurement of internal (personal) and external (environmental) factors, taking into account that family and social environment variables of resilience play very important roles in an individual's resilience. Protection factors seem to be more important in the development of resilience than risk factors. Resilience is a process that lasts a lifetime, with periods of acquisition and maintenance, and reduction and loss for assessment. Overall, currently available data on resilience suggest the presence of a neurobiological substrate, based largely on genetics, which correlates with personality traits, some of which are configured via social learning. The major questions about resilience revolve around properly defining the concept, identifying the factors involved in its development and recognizing whether it is actually possible to immunize mental health against adversities. In the clinical field, it may be possible to identify predisposing factors or risk factors for psychopathologies and to develop new intervention strategies, both preventive and therapeutic, based on the concept of resilience. The preferred environments for application of resilience are health, education, and social policy and the right approach in integrating; it can be developed only with more research
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Resilience in nurses: an integrative review.
Hart, Patricia L; Brannan, Jane D; De Chesnay, Mary
2014-09-01
To describe nursing research that has been conducted to understand the phenomenon of resilience in nurses. Resilience is the ability to bounce back or cope successfully despite adverse circumstances. Nurses deal with modern-day problems that affect their abilities to remain resilient. Nursing administrators/managers need to look for solutions not only to recruit nurses, but to become knowledgeable about how to support and retain nurses. A comprehensive search was undertaken for nursing research conducted between 1990 and 2011. Key search terms were nurse, resilience, resiliency and resilient. Whittemore and Knafl's integrative approach was used to conduct the methodological review. Challenging workplaces, psychological emptiness, diminishing inner balance and a sense of dissonance are contributing factors for resilience. Examples of intrapersonal characteristics include hope, self-efficacy and coping. Cognitive reframing, toughening up, grounding connections, work-life balance and reconciliation are resilience building strategies. This review provides information about the concept of resilience. Becoming aware of contributing factors to the need for resilience and successful strategies to build resilience can help in recruiting and retaining nurses. Understanding the concept of resilience can assist in providing support and developing programmes to help nurses become and stay resilient. © 2012 John Wiley & Sons Ltd.
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Dade County Public Schools, Miami, FL.
This document presents an outline for a 135-hour course designed to familiarize the student with manipulative skills and theoretical knowledge concerning aircraft instrument systems like major flight and engine instruments; fire protection and fire fighting systems; warning systems and navigation systems; aircraft cabin control systems, such as…
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Hanson, Curt
2014-01-01
An adaptive augmenting control algorithm for the Space Launch System has been developed at the Marshall Space Flight Center as part of the launch vehicles baseline flight control system. A prototype version of the SLS flight control software was hosted on a piloted aircraft at the Armstrong Flight Research Center to demonstrate the adaptive controller on a full-scale realistic application in a relevant flight environment. Concerns regarding adverse interactions between the adaptive controller and a proposed manual steering mode were investigated by giving the pilot trajectory deviation cues and pitch rate command authority.
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Fu, Christine; Leoutsakos, Jeannie-Marie; Underwood, Carol
2013-12-01
This study is an evaluation of a psychosocial intervention involving child and adolescent survivors of the 2008 Sichuan China earthquake. Sociodemographics, earthquake-related risk exposure, resilience using the Connor-Davidson Resilience Scale, and posttraumatic stress disorder (PTSD) using the UCLA-PTSD Index were collected from 1,988 intervention participants and 2,132 controls. Mean resilience scores and the odds of PTSD did not vary between groups. The independent factors for risk and resilience and the dependent variable, PTSD, in the measurement models between control and intervention groups were equivalent. The structural model of risk and 2 resilience factors on PTSD was examined and found to be unequivalent between groups. In contrast to controls, risk exposure (B = −0.32, p Rational thinking (B = −0.48, p < .001), a resilience factor, was more negatively associated with PTSD in the intervention group. The second resilience factor explored, self-awareness, was positively associated with PTSD in both groups (B = 0.46 for controls, p < .001, and B = 0.69 for intervention, p < .001). Results highlight the need for more cross-cultural research in resilience theory to develop culturally appropriate interventions and evaluation measures.
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Towards resilient cities. Comparing approaches/strategies
Directory of Open Access Journals (Sweden)
Angela Colucci
2012-07-01
Full Text Available The term “resilience” is used in many disciplines with different meanings. We will adopt the ecological concept of resilience, which epitomises the capacity of a system to adapt itself in response to the action of a force, achieving a state of equilibrium different from the original (White, 2011. Since the end of the last century, with a significant increase over the last few years, resilience has featured as key concept in many technical, political papers and documents, and appears in many researches. Of all this recent and varied range of literature, our focus is on those texts that combine resilience with strategies, processes and models for resilient cities, communities and regions. Starting from the resilience strategies developed as response for risks mitigation, the paper thus explores other approaches and experiences on cities resilience that have been conducted: the aim is to compare and identify innovation in the planning process towards risks mitigation. In this paper we present a summary of the initial survey stage of our research, with three main aims: understanding the approaches to resilience developed so far and identifying which aspects these approaches share (or not;understanding which strategies are being proposed for resilient regions, cities or social-ecological systems;understanding whether proposed resilience strategies involve innovations in urban and regional development disciplines. The aim is to understand whether the proposed concept of resilience, or rather strategies, constitute progress and contribute to innovation in the areas of urban planning and design in relation to risk mitigation. Three main families of literature have been identified from the recent literature promoting resilience as a key strategy. The first aim of the research is to understand which particular concept and which aspects of resilience are used, which resilience strategies are proposed, how the term ‘city’ is defined and interpreted
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Directory of Open Access Journals (Sweden)
Ju Ryoung Moon
2017-09-01
Full Text Available ObjectivesParental rearing behavior is one factor that influences the strength of resilience. In turn, resilience influences depression. However, it is unclear whether resilience has a mediating effect on the relationship between parental rearing and depression in adolescents with congenital heart disease (CHD. Therefore, the associations between parental rearing behavior and resilience and between rearing behavior and symptoms of depression were investigated with respect to age, gender and disease severity.Subjects and methodsPatients completed a parental rearing behavior questionnaire, a resilience scale and the Children’s Depression Inventory during a routine clinic visit. Structural equation modeling with maximum likelihood estimation was used to analyze the data.ResultsThe median age of the 180 patients included in the study was 17.8 years, and 64% were male. Lower resilience was found to be associated with overprotection, punishment, rejection, and control. There was a strong relationship between resilience and symptoms of depression. Resilience varied according to gender, age group, and disease severity.ConclusionParental rearing behaviors such as emotional warmth, rejection, punishment, control, and overprotection have a significant influence on adolescent’s resilience. When developing intervention programs to increase resilience and reduce depression in adolescents with CHD, parenting attitudes, gender, age, and CHD severity should be considered.
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Application of robust control to a rotary-wing aircraft
Turkoglu, Ercument
The thesis is concerned with the application of robust controller synthesis and analysis tools to a rotary-wing aircraft: the Bell 205 teetering-rotor helicopter. The Tioo loop-shaping approach is central to the work and two main issues concerned with its application will be considered. Firstly, the construction of diagonal (structured) and non- diagonal (unstructured) weighting functions will be considered. Secondly, the analysis of the implications of different weighting function structures in the controller implementation. A two stage cross-comparative analysis of a series of 1 Dof (Degree of Freedom) and 2 Dof controllers synthesized with both diagonal and non-diagonal weights using the Hqo loop- shaping technique will be presented for square and non-square multi input multi output, unstable, non-minimum phase and ill-conditioned models of the helicopter. Handling qualities of each control law augmented system will be assessed quantitatively and qualitatively. A quantitative analysis, in view of the specifications in ADS-33E, will be given based on a combination of flight data from in-flight tested controllers and, desk-top simula tions run on a fully augmented 12 Dof nonlinear helicopter model provided by QinetiQ, UK. A qualitative analysis will be given based on the pilot comments compiled (in view of the Cooper-Harper handling qualities rating scale) from the evaluated in-flight control laws.
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Focusing the Meaning(s of Resilience: Resilience as a Descriptive Concept and a Boundary Object
Directory of Open Access Journals (Sweden)
Fridolin Simon. Brand
2007-06-01
Full Text Available This article reviews the variety of definitions proposed for "resilience" within sustainability science and suggests a typology according to the specific degree of normativity. There is a tension between the original descriptive concept of resilience first defined in ecological science and a more recent, vague, and malleable notion of resilience used as an approach or boundary object by different scientific disciplines. Even though increased conceptual vagueness can be valuable to foster communication across disciplines and between science and practice, both conceptual clarity and practical relevance of the concept of resilience are critically in danger. The fundamental question is what conceptual structure we want resilience to have. This article argues that a clearly specified, descriptive concept of resilience is critical in providing a counterbalance to the use of resilience as a vague boundary object. A clear descriptive concept provides the basis for operationalization and application of resilience within ecological science.
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Scheduling Aircraft Landings under Constrained Position Shifting
Balakrishnan, Hamsa; Chandran, Bala
2006-01-01
Optimal scheduling of airport runway operations can play an important role in improving the safety and efficiency of the National Airspace System (NAS). Methods that compute the optimal landing sequence and landing times of aircraft must accommodate practical issues that affect the implementation of the schedule. One such practical consideration, known as Constrained Position Shifting (CPS), is the restriction that each aircraft must land within a pre-specified number of positions of its place in the First-Come-First-Served (FCFS) sequence. We consider the problem of scheduling landings of aircraft in a CPS environment in order to maximize runway throughput (minimize the completion time of the landing sequence), subject to operational constraints such as FAA-specified minimum inter-arrival spacing restrictions, precedence relationships among aircraft that arise either from airline preferences or air traffic control procedures that prevent overtaking, and time windows (representing possible control actions) during which each aircraft landing can occur. We present a Dynamic Programming-based approach that scales linearly in the number of aircraft, and describe our computational experience with a prototype implementation on realistic data for Denver International Airport.
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Rees, Clare S; Breen, Lauren J; Cusack, Lynette; Hegney, Desley
2015-01-01
When not managed effectively, high levels of workplace stress can lead to several negative personal and performance outcomes. Some professional groups work in highly stressful settings and are therefore particularly at risk of conditions such as anxiety, depression, secondary traumatic stress, and burnout. However, some individuals are less affected by workplace stress and the associated negative outcomes. Such individuals have been described as "resilient." A number of studies have found relationships between levels of individual resilience and specific negative outcomes such as burnout and compassion fatigue. However, because psychological resilience is a multi-dimensional construct it is necessary to more clearly delineate it from other related and overlapping constructs. The creation of a testable theoretical model of individual workforce resilience, which includes both stable traits (e.g., neuroticism) as well as more malleable intrapersonal factors (e.g., coping style), enables information to be derived that can eventually inform interventions aimed at enhancing individual resilience in the workplace. The purpose of this paper is to introduce a new theoretical model of individual workforce resilience that includes several intrapersonal constructs known to be central in the appraisal of and response to stressors and that also overlap with the construct of psychological resilience. We propose a model in which psychological resilience is hypothesized to mediate the relationship between neuroticism, mindfulness, self-efficacy, coping, and psychological adjustment.
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Adaptive Neural Network Sliding Mode Control for Quad Tilt Rotor Aircraft
Directory of Open Access Journals (Sweden)
Yanchao Yin
2017-01-01
Full Text Available A novel neural network sliding mode control based on multicommunity bidirectional drive collaborative search algorithm (M-CBDCS is proposed to design a flight controller for performing the attitude tracking control of a quad tilt rotors aircraft (QTRA. Firstly, the attitude dynamic model of the QTRA concerning propeller tension, channel arm, and moment of inertia is formulated, and the equivalent sliding mode control law is stated. Secondly, an adaptive control algorithm is presented to eliminate the approximation error, where a radial basis function (RBF neural network is used to online regulate the equivalent sliding mode control law, and the novel M-CBDCS algorithm is developed to uniformly update the unknown neural network weights and essential model parameters adaptively. The nonlinear approximation error is obtained and serves as a novel leakage term in the adaptations to guarantee the sliding surface convergence and eliminate the chattering phenomenon, which benefit the overall attitude control performance for QTRA. Finally, the appropriate comparisons among the novel adaptive neural network sliding mode control, the classical neural network sliding mode control, and the dynamic inverse PID control are examined, and comparative simulations are included to verify the efficacy of the proposed control method.
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An Optimal Augmented Monotonic Tracking Controller for Aircraft Engines with Output Constraints
Directory of Open Access Journals (Sweden)
Jiakun Qin
2017-01-01
Full Text Available This paper proposes a novel min-max control scheme for aircraft engines, with the aim of transferring a set of regulated outputs between two set-points, while ensuring a set of auxiliary outputs remain within prescribed constraints. In view of this, an optimal augmented monotonic tracking controller (OAMTC is proposed, by considering a linear plant with input integration, to enhance the ability of the control system to reject uncertainty in system parameters and ensure no crossing limits. The key idea is to use the eigenvalue and eigenvector placement method and genetic algorithms to shape the output responses. The approach is validated by numerical simulation. The results show that the designed OAMTC controller can achieve a satisfactory dynamic and steady performance and keep the auxiliary outputs within constraints in the transient regime.
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DEFF Research Database (Denmark)
dunn cavelty, myriam; Kaufmann, Mareile; Kristensen, Kristian Søby
2015-01-01
, and redefine relations of security and insecurity. We show the increased attention – scholarly as well as political – given to resilience in recent times and provide a review of the state of critical security studies literature on resilience. We argue that to advance this discussion, resilience needs...
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Resilience Management System And Development Of Resilience Capability On Site Workers
Komatsubara, Akinori
2013-01-01
When we consider the safety of socio-technical or safety critical systems, discussions from three layers are required; safety strategy, safety management and safety activity. In this study, development of resilience safety from the three layers is discussed. For the safety management layer, this study proposes resilience management system (RMS) as the style of safety management system (SMS) for resilience safety approach. Two cases at Japanese companies to enhance attitude and non-technical s...
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Directory of Open Access Journals (Sweden)
T. V. Gras’Ko
2014-01-01
Full Text Available The paper describes choosing and substantiating the control laws, forming the appearance the automatic control system for regulated high temperature main combustion chamber of maneuverable aircraft multimode gas turbine engine aimed at sustainable and effective functioning of main combustion chamber within a broad operation range.
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Aerodynamics/ACEE: Aircraft energy efficiency
1981-01-01
An overview is presented of a 10 year program managed by NASA which seeks to make possible the most efficient use of energy for aircraft propulsion and lift as well as provide a technology that can be used by U.S. manufacturers of air transports and engines. Supercritical wings, winglets, vortex drag reduction, high lift, active control, laminar flow control, and aerodynamics by computer are among the topics discussed. Wind tunnel models in flight verification of advanced technology, and the design, construction and testing of various aircraft structures are also described.
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Allan, John F.; McKenna, Jim; Dominey, Susan
2014-01-01
University inductees may be increasingly vulnerable to stressors during transition into higher education (HE), requiring psychological resilience to achieve academic success. This study aimed to profile inductees' resilience and to investigate links to prospective end of year academic outcomes. Scores for resilience were based on a validated…
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Belcastro, Christine M.; Newman, Richard L.; Crider, Dennis A.; Klyde, David H.; Foster, John V.; Groff, Loren
2016-01-01
Aircraft loss of control (LOC) is a leading cause of fatal accidents across all transport airplane and operational classes. LOC can result from a wide spectrum of precursors (or hazards), often occurring in combination. Technologies developed for LOC prevention and recovery must therefore be effective under a wide variety of conditions and uncertainties, including multiple hazards, and the validation process must provide a means of assessing system effectiveness and coverage of these hazards. This paper provides a detailed description of a methodology for analyzing LOC as a dynamics and control problem for the purpose of developing effective technology solutions. The paper includes a definition of LOC based on several recent publications, a detailed description of a refined LOC accident analysis process that is illustrated via selected example cases, and a description of planned follow-on activities for identifying future potential LOC risks and the development of LOC test scenarios. Some preliminary considerations for LOC of Unmanned Aircraft Systems (UAS) and for their safe integration into the National Airspace System (NAS) are also discussed.
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Redundant actuator development study. [flight control systems for supersonic transport aircraft
Ryder, D. R.
1973-01-01
Current and past supersonic transport configurations are reviewed to assess redundancy requirements for future airplane control systems. Secondary actuators used in stability augmentation systems will probably be the most critical actuator application and require the highest level of redundancy. Two methods of actuator redundancy mechanization have been recommended for further study. Math models of the recommended systems have been developed for use in future computer simulations. A long range plan has been formulated for actuator hardware development and testing in conjunction with the NASA Flight Simulator for Advanced Aircraft.
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Adaptive Flight Control Design with Optimal Control Modification on an F-18 Aircraft Model
Burken, John J.; Nguyen, Nhan T.; Griffin, Brian J.
2010-01-01
In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to as the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly; however, a large adaptive gain can lead to high-frequency oscillations which can adversely affect the robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient robustness. A damping term (v) is added in the modification to increase damping as needed. Simulations were conducted on a damaged F-18 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) with both the standard baseline dynamic inversion controller and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model.
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Foundations of resilience thinking.
Curtin, Charles G; Parker, Jessica P
2014-08-01
Through 3 broad and interconnected streams of thought, resilience thinking has influenced the science of ecology and natural resource management by generating new multidisciplinary approaches to environmental problem solving. Resilience science, adaptive management (AM), and ecological policy design (EPD) contributed to an internationally unified paradigm built around the realization that change is inevitable and that science and management must approach the world with this assumption, rather than one of stability. Resilience thinking treats actions as experiments to be learned from, rather than intellectual propositions to be defended or mistakes to be ignored. It asks what is novel and innovative and strives to capture the overall behavior of a system, rather than seeking static, precise outcomes from discrete action steps. Understanding the foundations of resilience thinking is an important building block for developing more holistic and adaptive approaches to conservation. We conducted a comprehensive review of the history of resilience thinking because resilience thinking provides a working context upon which more effective, synergistic, and systems-based conservation action can be taken in light of rapid and unpredictable change. Together, resilience science, AM, and EPD bridge the gaps between systems analysis, ecology, and resource management to provide an interdisciplinary approach to solving wicked problems. © 2014 Society for Conservation Biology.
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Midwives׳ experiences of workplace resilience.
Hunter, Billie; Warren, Lucie
2014-08-01
many UK midwives experience workplace adversity resulting from a national shortage of midwives, rise in birth rate and increased numbers of women entering pregnancy with complex care needs. Research evidence suggests that workplace pressures, and the emotional demands of the job, may increase midwives׳ experience of stress and contribute to low morale, sickness and attrition. Much less is known about midwives who demonstrate resilience in the face of adversity. Resilience has been investigated in studies of other health and social care workers, but there is a gap in knowledge regarding midwives׳ experiences. to explore clinical midwives׳ understanding and experience of professional resilience and to identify the personal, professional and contextual factors considered to contribute to or act as barriers to resilience. an exploratory qualitative descriptive study. In Stage One, a closed online professional discussion group was conducted over a one month period. Midwives discussed workplace adversity and their resilient responses to this. In Stage Two, the data were discussed with an Expert Panel with representatives from midwifery workforce and resilience research, in order to enhance data interpretation and refine the concept modelling. the online discussion group was hosted by the Royal College of Midwives, UK online professional networking hub: 'Communities'. 11 practising midwives with 15 or more years of 'hands on clinical experience', and who self-identified as being resilient, took part in the online discussion group. thematic analysis of the data identified four themes: challenges to resilience, managing and coping, self-awareness and building resilience. The participants identified 'critical moments' in their careers when midwives were especially vulnerable to workplace adversity. Resilience was seen as a learned process which was facilitated by a range of coping strategies, including accessing support and developing self-awareness and protection of self
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Resilience among Military Youth
Easterbrooks, M. Ann; Ginsburg, Kenneth; Lerner, Richard M.
2013-01-01
In this article, the authors present their approach to understanding resilience among military connected young people, and they discuss some of the gaps in their knowledge. They begin by defining resilience, and then present a theoretical model of how young people demonstrate resilient functioning. Next they consider some of the research on…
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Fast and error-resilient coherent control in an atomic vapor
He, Yizun; Wang, Mengbing; Zhao, Jian; Qiu, Liyang; Wang, Yuzhuo; Fang, Yami; Zhao, Kaifeng; Wu, Saijun
2017-04-01
Nanosecond chirped pulses from an optical arbitrary waveform generator is applied to both invert and coherently split the D1 line population of potassium vapor within a laser focal volume of 2X105 μ m3. The inversion fidelity of f>96%, mainly limited by spontaneous emission during the nanosecond pulse, is inferred from both probe light transmission and superfluorescence emission. The nearly perfect inversion is uniformly achieved for laser intensity varying over an order of magnitude, and is tolerant to detuning error of more than 1000 times the D1 transition linewidth. We further demonstrate enhanced intensity error resilience with multiple chirped pulses and ``universal composite pulses''. This fast and robust coherent control technique should find wide applications in the field of quantum optics, laser cooling, and atom interferometry. This work is supported by National Key Research Program of China under Grant No. 2016YFA0302000, and NNSFC under Grant No. 11574053.
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DeLaat, John C.; Kopasakis, George; Saus, Joseph R.; Chang, Clarence T.; Wey, Changlie
2012-01-01
Lean combustion concepts for aircraft engine combustors are prone to combustion instabilities. Mitigation of instabilities is an enabling technology for these low-emissions combustors. NASA Glenn Research Center s prior activity has demonstrated active control to suppress a high-frequency combustion instability in a combustor rig designed to emulate an actual aircraft engine instability experience with a conventional, rich-front-end combustor. The current effort is developing further understanding of the problem specifically as applied to future lean-burning, very low-emissions combustors. A prototype advanced, low-emissions aircraft engine combustor with a combustion instability has been identified and previous work has characterized the dynamic behavior of that combustor prototype. The combustor exhibits thermoacoustic instabilities that are related to increasing fuel flow and that potentially prevent full-power operation. A simplified, non-linear oscillator model and a more physics-based sectored 1-D dynamic model have been developed to capture the combustor prototype s instability behavior. Utilizing these models, the NASA Adaptive Sliding Phasor Average Control (ASPAC) instability control method has been updated for the low-emissions combustor prototype. Active combustion instability suppression using the ASPAC control method has been demonstrated experimentally with this combustor prototype in a NASA combustion test cell operating at engine pressures, temperatures, and flows. A high-frequency fuel valve was utilized to perturb the combustor fuel flow. Successful instability suppression was shown using a dynamic pressure sensor in the combustor for controller feedback. Instability control was also shown with a pressure feedback sensor in the lower temperature region upstream of the combustor. It was also demonstrated that the controller can prevent the instability from occurring while combustor operation was transitioning from a stable, low-power condition to
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Optimization of actuator arrays for aircraft interior noise control
Cabell, R. H.; Lester, H. C.; Mathur, G. P.; Tran, B. N.
1993-01-01
A numerical procedure for grouping actuators in order to reduce the number of degrees of freedom in an active noise control system is evaluated using experimental data. Piezoceramic actuators for reducing aircraft interior noise are arranged into groups using a nonlinear optimization routine and clustering algorithm. An actuator group is created when two or more actuators are driven with the same control input. This procedure is suitable for active control applications where actuators are already mounted on a structure. The feasibility of this technique is demonstrated using measured data from the aft cabin of a Douglas DC-9 fuselage. The measured data include transfer functions between 34 piezoceramic actuators and 29 interior microphones and microphone responses due to the primary noise produced by external speakers. Control inputs for the grouped actuators were calculated so that a cost function, defined as a quadratic pressure term and a penalty term, was a minimum. The measured transfer functions and microphone responses are checked by comparing calculated noise reductions with measured noise reductions for four frequencies. The grouping procedure is then used to determine actuator groups that improve overall interior noise reductions by 5.3 to 15 dB, compared to the baseline experimental configuration.
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Wlezien, R. W.; Horner, G. C.; McGowan, A. R.; Padula, S. L.; Scott, M. A.; Silcox, R. J.; Simpson, J. O.
1998-01-01
In the last decade smart technologies have become enablers that cut across traditional boundaries in materials science and engineering. Here we define smart to mean embedded actuation, sensing, and control logic in a tightly coupled feedback loop. While multiple successes have been achieved in the laboratory, we have yet to see the general applicability of smart devices to real aircraft systems. The NASA Aircraft Morphing program is an attempt to couple research across a wide range of disciplines to integrate smart technologies into high payoff aircraft applications. The program bridges research in seven individual disciplines and combines the effort into activities in three primary program thrusts. System studies are used to assess the highest- payoff program objectives, and specific research activities are defined to address the technologies required for development of smart aircraft systems. In this paper we address the overall program goals and programmatic structure, and discuss the challenges associated with bringing the technologies to fruition.
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Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.
1996-05-01
The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.
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Bennett, Joel B; Neeper, Michael; Linde, Brittany D; Lucas, Gale M; Simone, Lindsay
2018-05-02
The majority of resilience interventions focus on the individual. Workplace resilience is a growing field of research. Given the ever-increasing interconnectedness in businesses, teamwork is a guarantee. There is also growing recognition that resilience functions at the team level. The objective of our work was to address three shortcomings in the study of workplace resilience interventions: lack of interventions focusing on group-level or team resilience, the need for brief interventions, and the need for more theoretical precision in intervention studies. The authors took an established evidence-based program (Team Resilience) and modified it based on these needs. A working model for brief intervention evaluation distinguishes outcomes that are proximal (perceptions that the program improved resilience) and distal (dispositional resilience). A total of 7 hypotheses tested the model and program efficacy. Two samples (n=118 and n=181) of engineering firms received the Web-based training and provided immediate reactions in a posttest-only design. The second sample also included a control condition (n=201). The findings support the model and program efficacy. For example, workplace resilience was greater in the intervention group than in the control group. Other findings suggest social dissemination effects, equal outcomes for employees at different stress levels, and greater benefit for females. This preliminary research provides evidence for the capabilities of e-learning modules to effectively promote workplace resilience and a working model of team resilience. ©Joel B Bennett, Michael Neeper, Brittany D Linde, Gale M Lucas, Lindsay Simone. Originally published in JMIR Mental Health (http://mental.jmir.org), 02.05.2018.
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Fault Tolerance, Diagnostics, and Prognostics in Aircraft Flight
National Aeronautics and Space Administration — Abstract In modern fighter aircraft with statically unstable airframe designs, the flight control system is considered flight critical, i.e. the aircraft will...
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A low cost maritime control aircraft-ship-weapons system. [antiship missile defense
Fluk, H.
1981-01-01
It is pointed out that the long-range antiship standoff missile is emerging as the foremost threat on the seas. Delivered by high speed bombers, surface ships, and submarines, a missile attack can be mounted against selected targets from any point on the compass. An investigation is conducted regarding the configuration of a system which could most efficiently identify and destroy standoff threats before they launch their weapons. It is found that by using ships for carrying and launching missiles, and employing aircraft with a powerful radar only for search and missile directing operations, aircraft cost and weight can be greatly reduced. The employment of V/STOL aircraft in preference to other types of aircraft makes it possible to use ships of smaller size for carrying the aircraft. However, in order to obtain an all-weather operational capability for the system, ships are selected which are still big enough to display the required stability in heavy seas.
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Directory of Open Access Journals (Sweden)
Akhtar Hussain
2017-02-01
Full Text Available The resiliency of power systems can be enhanced during emergency situations by using microgrids, due to their capability to supply local loads. However, precise prediction of disturbance events is very difficult rather the occurrence probability can be expressed as, high, medium, or low, etc. Therefore, a fuzzy logic-based battery energy storage system (BESS operation controller is proposed in this study. In addition to BESS state-of-charge and market price signals, event occurrence probability is taken as crisp input for the BESS operation controller. After assessing the membership levels of all the three inputs, BESS operation controller decides the operation mode (subservient or resilient of BESS units. In subservient mode, BESS is fully controlled by an energy management system (EMS while in the case of resilient mode, the EMS follows the commands of the BESS operation controller for scheduling BESS units. Therefore, the proposed hybrid microgrid model can operate in normal, resilient, and emergency modes with the respective objective functions and scheduling horizons. Due to the consideration of resilient mode, load curtailment can be reduced during emergency operation periods. Numerical simulations have demonstrated the effectiveness of the proposed strategy for enhancing the resiliency of hybrid microgrids.
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Urban flooding and Resilience: concepts and needs
Gourbesville, Ph.
2012-04-01
During the recent years, a growing interest for resilience has been expressed in the natural disaster mitigation area and especially in the flood related events. The European Union, under the Seventh Framework Programme (FP7), has initiated several research initiatives in order to explore this concept especially for the urban environments. Under urban resilience is underlined the ability of system potentially exposed to hazard to resist, respond, recover and reflect up to stage which is enough to preserve level of functioning and structure. Urban system can be resilient to lot of different hazards. Urban resilience is defined as the degree to which cities are able to tolerate some disturbance before reorganizing around a new set of structures and processes (Holling 1973, De Bruijn 2005). The United Nation's International strategy for Disaster Reductions has defined resilience as "the capacity of a system, community or society potentially exposed to hazards to adapt, by resisting or changing in order to reach and maintain an acceptable level of functioning and structure. This is determined by the degree to which the social system is capable of organizing itself to increase this capacity for learning from past disasters for better future protection and to improve risk reduction measures."(UN/ISDR 2004). According to that, system should be able to accept the hazard and be able to recover up to condition that provides acceptable operational level of city structure and population during and after hazard event. Main elements of urban system are built environment and population. Physical characteristic of built environment and social characteristic of population have to be examined in order to evaluate resilience. Therefore presenting methodology for assessing flood resilience in urban areas has to be one of the focal points for the exposed cities. Strategies under flood management planning related to resilience of urban systems are usually regarding controlling runoff
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U.S. Geological Survey Unmanned Aircraft Systems (UAS) Roadmap 2014
Cress, Jill J.; Hutt, Michael E.; Sloan, Jeff L.; Bauer, Mark A.; Feller, Mark R.; Goplen, Susan E.
2015-01-01
The U.S. Department of the Interior (DOI) is responsible for protecting the natural resources and heritage contained on almost 20 percent of the land in the United States. This responsibility requires acquisition of remotely sensed data throughout vast lands, including areas that are remote and potentially dangerous to access. One promising new technology for data collection is unmanned aircraft systems (UAS), which may be better suited (achieving superior science, safety, and savings) than traditional methods. UAS, regardless of their size, have the same operational components: aircraft, payloads, communications unit, and operator control unit. The aircraft is the platform that flies and carries any required payloads. For Department of the Interior missions these payloads will be either a sensor or set of sensors that can acquire the specific type of remotely sensed data that is needed. The aircraft will also carry the payload that is responsible for transmitting live airborne video images, compass headings, and location information to the operator control unit. The communications unit, which transfers information between the aircraft and the operator control unit, consists of the hardware and software required to establish both uplink and downlink communications. Finally, the operator control unit both controls and monitors the aircraft and can be operated either by a pilot on the ground or autonomously.
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Broderick, Ron
1997-01-01
The ultimate goal of this report was to integrate the powerful tools of artificial intelligence into the traditional process of software development. To maintain the US aerospace competitive advantage, traditional aerospace and software engineers need to more easily incorporate the technology of artificial intelligence into the advanced aerospace systems being designed today. The future goal was to transition artificial intelligence from an emerging technology to a standard technology that is considered early in the life cycle process to develop state-of-the-art aircraft automation systems. This report addressed the future goal in two ways. First, it provided a matrix that identified typical aircraft automation applications conducive to various artificial intelligence methods. The purpose of this matrix was to provide top-level guidance to managers contemplating the possible use of artificial intelligence in the development of aircraft automation. Second, the report provided a methodology to formally evaluate neural networks as part of the traditional process of software development. The matrix was developed by organizing the discipline of artificial intelligence into the following six methods: logical, object representation-based, distributed, uncertainty management, temporal and neurocomputing. Next, a study of existing aircraft automation applications that have been conducive to artificial intelligence implementation resulted in the following five categories: pilot-vehicle interface, system status and diagnosis, situation assessment, automatic flight planning, and aircraft flight control. The resulting matrix provided management guidance to understand artificial intelligence as it applied to aircraft automation. The approach taken to develop a methodology to formally evaluate neural networks as part of the software engineering life cycle was to start with the existing software quality assurance standards and to change these standards to include neural network
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Governance and Capacity to Manage Resilience of Health Systems: Towards a New Conceptual Framework
Directory of Open Access Journals (Sweden)
Karl Blanchet
2017-08-01
Full Text Available The term resilience has dominated the discourse among health systems researchers since 2014 and the onset of the Ebola outbreak in West Africa. There is wide consensus that the global community has to help build more resilient health systems. But do we really know what resilience means, and do we all have the same vision of resilience? The present paper presents a new conceptual framework on governance of resilience based on systems thinking and complexity theories. In this paper, we see resilience of a health system as its capacity to absorb, adapt and transform when exposed to a shock such as a pandemic, natural disaster or armed conflict and still retain the same control over its structure and functions.
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Branco, B. F.; Fano, E.; Adams, J.; Shon, L.; Zimmermann, A.; Sioux, H.; Gillis, A.
2017-12-01
Public schools and youth voices are largely absent from climate resilience planning and projects in New York City. Additionally, research shows that U.S. science teachers' understanding of climate science is lacking, hence there is not only an urgent need to train and support teachers on both the science and pedagogy of climate change, but to link climate literacy, resilience thinking and service learning in K-12 education. However, research on participation of students and teachers in authentic, civic-oriented experiences points to increased engagement and learning outcomes in science. The Resilient Schools Consortium (RiSC) Project will address all these needs through an afterschool program in six coastal Brooklyn schools that engages teachers and urban youth (grades 6-12), in school and community climate resilience assessment and project design. The RiSC climate curriculum, co-designed by New York City school teachers with Brooklyn College, the National Wildlife Federation, New York Sea Grant and the Science and Resilience Institute at Jamaica Bay, will begin by helping students to understand the difference between climate and weather. The curriculum makes extensive use of existing resources such as NOAA's Digital Coast and the Coastal Resilience Mapping Portal. Through a series of four modules over two school years, the six RiSC teams will; 1. explore and understand the human-induced drivers of climate change and, particularly, the significant climate and extreme weather related risks to their schools and surrounding communities; 2. complete a climate vulnerability assessment within the school and the community that is aligned to OneNYC - the city's resilience planning document; 3. design and execute a school-based resilience project; and 4. propose resilience guidelines for NYC Department of Education schools. At the end of each school year, the six RiSC teams will convene a RiSC summit with city officials and resilience practitioners to share ideas and
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Donnell, K.O.; Schober, S.; Stolk, M.; Marzocca, P.; De Breuker, R.; Abdalla, M.; Nicolini, E.; Gürdal, Z.
2007-01-01
This paper discusses modeling, simulations and experimental aspects of active aeroelastic control on aircraft wings by using Synthetic Jet Actuators (SJAs). SJAs, a particular class of zero-net mass-flux actuators, have shown very promising results in numerous aeronautical applications, such as
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Arena, Maurizio; Noviello, Maria Chiara; Rea, Francesco; Amoroso, Francesco; Pecora, Rosario
2018-03-01
The design and application of adaptive devices are currently ambitious targets in the field of aviation research addressed at new generation aircraft. The development of intelligent structures involves aspects of multidisciplinary nature: the combination of compact architectures, embedded electrical systems and smart materials, allows for developing a highly innovative device. The paper aims to present the control system design of an innovative morphing flap tailored for the next generation regional aircraft, within Clean Sky 2 - Airgreen 2 European Research Scenario. A distributed system of electromechanical actuators (EMAs) has been sized to enable up to three operating modes of a structure arranged in four blocks along the chord-wise direction: •overall camber-morphing; •upwards/downwards deflection and twisting of the final tip segment. A state-of-art feedback logic based on a decentralized control strategy for shape control is outlined, including the results of dynamic stability analysis based on the blocks rational schematization within Matlab/Simulink® environment. Such study has been performed implementing a state-space model, considering also design parameters as the torsional stiffness and damping of the actuation chain. The design process is flowing towards an increasingly "robotized" system, which can be externally controlled to perform certain operations. Future developments will be the control laws implementation as well as the functionality test on a real flap prototype.
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Guilera, Georgina; Pereda, Noemí; Paños, Ana; Abad, Judit
2015-07-11
The concept and assessment of resilience have attracted considerable attention in recent years, but none of the instruments developed to measure resilience in adolescents have been adapted to the Spanish context. The Adolescent Resilience Questionnaire (ARQ) provides a comprehensive and multidimensional assessment of the resources associated with resilience in adolescents. This study analyzes the psychometric properties of the ARQ. Participants included a community sample of 1101 Spanish adolescents (53.5 % boys) aged 12-17 years (M = 14.51; SD = 1.755). Results confirm the factor structure based on 12 scales. Internal consistency was generally adequate (between .60 and .84), although the unacceptable coefficient for the Empathy/Tolerance scale (α = .38) means that this scale needs to be revised for the Spanish context. Relationships between ARQ scales and psychopathology were in the expected direction and magnitude. Some gender differences were observed, with higher scores for boys on Confidence and Negative cognition. The Spanish version of the ARQ can help to identify personal characteristics associated with resilience and signs of positive engagement with family, peers, school, and the community. It can identify those adolescents most likely to show resilience in response to adversity, as well as those who may be vulnerable under situations of stress.
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Modern trends of aircraft fly-by-wire systems
Directory of Open Access Journals (Sweden)
С. С. Юцкевич
2013-07-01
Full Text Available Specifics of civil aviation modern transport aircraft fly-by-wire control systems are described. A comparison of the systems-level hardware and software, expressed through modes of guidance, provision of aircraft Airbus A-320, Boeing B-777, Tupolev Tu-214, Sukhoi Superjet SSJ-100 are carried out. The possibility of transition from mechanical control wiring to control through fly-by-wire system in the backup channel is shown.
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Haptic-Multimodal Flight Control System Update
Goodrich, Kenneth H.; Schutte, Paul C.; Williams, Ralph A.
2011-01-01
The rapidly advancing capabilities of autonomous aircraft suggest a future where many of the responsibilities of today s pilot transition to the vehicle, transforming the pilot s job into something akin to driving a car or simply being a passenger. Notionally, this transition will reduce the specialized skills, training, and attention required of the human user while improving safety and performance. However, our experience with highly automated aircraft highlights many challenges to this transition including: lack of automation resilience; adverse human-automation interaction under stress; and the difficulty of developing certification standards and methods of compliance for complex systems performing critical functions traditionally performed by the pilot (e.g., sense and avoid vs. see and avoid). Recognizing these opportunities and realities, researchers at NASA Langley are developing a haptic-multimodal flight control (HFC) system concept that can serve as a bridge between today s state of the art aircraft that are highly automated but have little autonomy and can only be operated safely by highly trained experts (i.e., pilots) to a future in which non-experts (e.g., drivers) can safely and reliably use autonomous aircraft to perform a variety of missions. This paper reviews the motivation and theoretical basis of the HFC system, describes its current state of development, and presents results from two pilot-in-the-loop simulation studies. These preliminary studies suggest the HFC reshapes human-automation interaction in a way well-suited to revolutionary ease-of-use.
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Alexander, H. R.; Smith, K. E.; Mcveigh, M. A.; Dixon, P. G.; Mcmanus, B. L.
1979-01-01
Composite structures technology is applied in a preliminary design study of advanced technology blades and hubs for the XV-15 tilt rotor research demonstrator aircraft. Significant improvements in XV-15 hover and cruise performance are available using blades designed for compatibility with the existing aircraft, i.e., blade installation would not require modification of the airframe, hub or upper controls. Provision of a low risk nonmechanical control system was also studied, and a development specification is given.
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Diehl, Manfred; Hay, Elizabeth L
2010-09-01
This study observed young, middle-aged, and older adults (N = 239; Mage = 49.6 years; range = 18-89 years) for 30 consecutive days to examine the association between daily stress and negative affect, taking into account potential risk (i.e., self-concept incoherence) and resilience (i.e., age, perceived personal control) factors. Results indicated that younger individuals and individuals with a more incoherent self-concept showed higher average negative affect across the study. As well, individuals reported higher negative affect on days that they experienced more stress than usual and on days that they reported less control than usual. These main effects were qualified by significant interactions. In particular, the association between daily stress and negative affect was stronger on days on which adults reported low control compared with days on which they reported high control (i.e., perceptions of control buffered stress). Reactivity to daily stress did not differ for individuals of different ages or for individuals with different levels of self-concept incoherence. Although all individuals reported higher negative affect on days on which they reported less control than usual, this association was more pronounced among younger adults. The current study helps to elucidate the role of risk and resilience factors when adults are faced with daily stress.
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Resilience Design Patterns: A Structured Approach to Resilience at Extreme Scale
International Nuclear Information System (INIS)
Engelmann, Christian; Hukerikar, Saurabh
2017-01-01
Reliability is a serious concern for future extreme-scale high-performance computing (HPC) systems. Projections based on the current generation of HPC systems and technology roadmaps suggest the prevalence of very high fault rates in future systems. While the HPC community has developed various resilience solutions, application-level techniques as well as system-based solutions, the solution space remains fragmented. There are no formal methods and metrics to integrate the various HPC resilience techniques into composite solutions, nor are there methods to holistically evaluate the adequacy and efficacy of such solutions in terms of their protection coverage, and their performance \\& power efficiency characteristics. Additionally, few of the current approaches are portable to newer architectures and software environments that will be deployed on future systems. In this paper, we develop a structured approach to the design, evaluation and optimization of HPC resilience using the concept of design patterns. A design pattern is a general repeatable solution to a commonly occurring problem. We identify the problems caused by various types of faults, errors and failures in HPC systems and the techniques used to deal with these events. Each well-known solution that addresses a specific HPC resilience challenge is described in the form of a pattern. We develop a complete catalog of such resilience design patterns, which may be used by system architects, system software and tools developers, application programmers, as well as users and operators as essential building blocks when designing and deploying resilience solutions. We also develop a design framework that enhances a designer's understanding the opportunities for integrating multiple patterns across layers of the system stack and the important constraints during implementation of the individual patterns. It is also useful for defining mechanisms and interfaces to coordinate flexible fault management across
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Mathematical model of an indirect action fuel flow controller for aircraft jet engines
Tudosie, Alexandru-Nicolae
2017-06-01
The paper deals with a fuel mass flow rate controller with indirect action for aircraft jet engines. The author has identified fuel controller's main parts and its operation mode, then, based on these observations, one has determined motion equations of each main part, which have built system's non-linear mathematical model. In order to realize a better study this model was linearised (using the finite differences method) and then adimensionalized. Based on this new form of the mathematical model, after applying Laplace transformation, the embedded system (controller+engine) was described by the block diagram with transfer functions. Some Simulink-Matlab simulations were performed, concerning system's time behavior for step input, which lead to some useful conclusions and extension possibilities.
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Zoogeomorphology and resilience theory
Butler, David R.; Anzah, Faisal; Goff, Paepin D.; Villa, Jennifer
2018-03-01
Zoogeomorphology, the study of animals as geomorphic agents, has been largely overlooked in the context of resilience theory and biogeomorphic systems. In this paper, examples are provided of the interactions between external landscape disturbances and zoogeomorphological agents. We describe cases in which naturally occurring zoogeomorphological agents occupy a landscape, and examine whether those zoogeomorphic agents provide resilience to a landscape or instead serve as a landscape stress capable of inducing a phase-state shift. Several cases are described whereby the presence of exotic (introduced) zoogeomorphic agents overwhelms a landscape and induce collapse. The impact of climate change on species with zoogeomorphological importance is discussed in the context of resilience of a landscape. We conclude with a summary diagram illustrating the relationships existing between zoogeomorphic impacts and landscape resilience in the context of our case studies, and speculate about the future of the study of zoogeomorphology in the framework of resilience theory.
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Tiered Approach to Resilience Assessment.
Linkov, Igor; Fox-Lent, Cate; Read, Laura; Allen, Craig R; Arnott, James C; Bellini, Emanuele; Coaffee, Jon; Florin, Marie-Valentine; Hatfield, Kirk; Hyde, Iain; Hynes, William; Jovanovic, Aleksandar; Kasperson, Roger; Katzenberger, John; Keys, Patrick W; Lambert, James H; Moss, Richard; Murdoch, Peter S; Palma-Oliveira, Jose; Pulwarty, Roger S; Sands, Dale; Thomas, Edward A; Tye, Mari R; Woods, David
2018-04-25
Regulatory agencies have long adopted a three-tier framework for risk assessment. We build on this structure to propose a tiered approach for resilience assessment that can be integrated into the existing regulatory processes. Comprehensive approaches to assessing resilience at appropriate and operational scales, reconciling analytical complexity as needed with stakeholder needs and resources available, and ultimately creating actionable recommendations to enhance resilience are still lacking. Our proposed framework consists of tiers by which analysts can select resilience assessment and decision support tools to inform associated management actions relative to the scope and urgency of the risk and the capacity of resource managers to improve system resilience. The resilience management framework proposed is not intended to supplant either risk management or the many existing efforts of resilience quantification method development, but instead provide a guide to selecting tools that are appropriate for the given analytic need. The goal of this tiered approach is to intentionally parallel the tiered approach used in regulatory contexts so that resilience assessment might be more easily and quickly integrated into existing structures and with existing policies. Published 2018. This article is a U.S. government work and is in the public domain in the USA.
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Hofer, A; Mizuno, Y; Wartelsteiner, F; Wolfgang Fleischhacker, W; Frajo-Apor, B; Kemmler, G; Mimura, M; Pardeller, S; Sondermann, C; Suzuki, T; Welte, A; Uchida, H
2017-10-01
Health-related quality of life (HRQOL) is significantly affected in individuals with schizophrenia or bipolar I disorder (BD-I). The current study investigated whether symptomatic remission and resilience might differently impact HRQOL in these patients. Fifty-two patients with schizophrenia and 60 patients suffering from BD-I from outpatient mental health services as well as 77 healthy control subjects from the general community were included into a cross-sectional study. HRQOL and resilience were assessed using the WHOQOL-BREF and the Resilience Scale. In patients, psychopathology was quantified by the Positive and Negative Syndrome Scale or the Montgomery Asberg Depression Rating Scale and the Young Mania Rating Scale, respectively. Notably, both patient groups showed lower HRQOL and resilience compared to control subjects, non-remitted patients indicated lower HRQOL than remitted ones. The effect of remission on HRQOL was significantly larger in patients with BD-I than in those with schizophrenia but did not explain the difference in HRQOL between groups. Resilience predicted HRQOL in all three groups. When accounting for the effect of resilience among remitted patients, only the difference in HRQOL between schizophrenia patients and control subjects was significant. These findings demonstrate the impact of symptomatic remission and resilience on HRQOL of both patients suffering from schizophrenia and BD-I and indicate that these factors are especially relevant for HRQOL of patients with BD-I. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Measuring resilience in integrated planning
DEFF Research Database (Denmark)
Apneseth, K.; Wahl, A. M.; Hollnagel, E.
2013-01-01
This chapter demonstrates how a Resilience Analysis Grid (RAG) can be used to profile the performance of a company in terms of the four abilities that characterize a resilient organization. It describes the development of a new, RAG-based tool founded on Resilience Engineering principles that can...... be used to assess an organization's resilience. The tool was tested in a case study involving a company in the offshore oil and gas industry. The company had decided to adopt an Integrated Operations (IO) approach to operations and maintenance planning and the tool was used to evaluate the impact...... of the Integrated Planning (IPL) process on its resilience....
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A Survey of Intelligent Control and Health Management Technologies for Aircraft Propulsion Systems
Litt, Jonathan S.; Simon, Donald L.; Garg, Sanjay; Guo, Ten-Heui; Mercer, Carolyn; Behbahani, Alireza; Bajwa, Anupa; Jensen, Daniel T.
2005-01-01
Intelligent Control and Health Management technology for aircraft propulsion systems is much more developed in the laboratory than in practice. With a renewed emphasis on reducing engine life cycle costs, improving fuel efficiency, increasing durability and life, etc., driven by various government programs, there is a strong push to move these technologies out of the laboratory and onto the engine. This paper describes the existing state of engine control and on-board health management, and surveys some specific technologies under development that will enable an aircraft propulsion system to operate in an intelligent way--defined as self-diagnostic, self-prognostic, self-optimizing, and mission adaptable. These technologies offer the potential for creating extremely safe, highly reliable systems. The technologies will help to enable a level of performance that far exceeds that of today s propulsion systems in terms of reduction of harmful emissions, maximization of fuel efficiency, and minimization of noise, while improving system affordability and safety. Technologies that are discussed include various aspects of propulsion control, diagnostics, prognostics, and their integration. The paper focuses on the improvements that can be achieved through innovative software and algorithms. It concentrates on those areas that do not require significant advances in sensors and actuators to make them achievable, while acknowledging the additional benefit that can be realized when those technologies become available. The paper also discusses issues associated with the introduction of some of the technologies.
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Fullen, Matthew C.; Gorby, Sean R.
2016-01-01
Resilience has been described as a paradigm for aging that is more inclusive than models that focus on physiological and functional abilities. We evaluated a novel program, Resilient Aging, designed to influence marginalized older adults' perceptions of their resilience, self-efficacy, and wellness. The multiweek group program incorporated an…
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McCann, Terence; Songprakun, Wallapa; Stephenson, John
2017-01-01
The growing incidence of depression in developing countries, such as Thailand, is placing increasing pressure on public mental health services, and those living in rural areas have limited access to mental health services and specialised support. Resilience is integral to the recovery of people with depression and to caregivers. This parallel group randomised controlled trial evaluated the effectiveness of a guided self-help manual in improving resilience in adults diagnosed with moderate dep...
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Probing Resilience: Daily Environmental Mastery, Self-Esteem, and Stress Appraisal.
Montpetit, Mignon A; Tiberio, Stacey S
2016-10-01
The current study explores one way the process of resilience arises by investigating the underlying process of stress appraisal. In particular, the analyses examine how resilience resources function each day to attenuate the extent to which life experiences are perceived as threatening, and how trait-like resilience resources shape the appraisal process. Daily diary and questionnaire data from 96 participants of Successful Aging in Context: The Macroenvironment and Daily Lived Experience (SAIC; MAge = 67 years, SDAge = 4.9 years; range: 58-86 years) were analyzed using multilevel random coefficient modeling to investigate how individuals' daily perceptions of control and self-esteem impacted perceived stress on a given day. Results suggested that both self-esteem and environmental mastery help mitigate the experience of stress; furthermore, dispositional resilience and self-esteem stability predict differences between individuals in the extent to which self-esteem tempers the perception of stress each day. The results inform theoretical and empirical work on the nature of resilience, especially regarding how the process arises in ordinary life. From an application perspective, results imply that augmenting environmental mastery and self-esteem, both of which are malleable, can facilitate resilience by helping elders challenge their perceptions of stress each day. © The Author(s) 2016.
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Resilience as an underexplored outcome of workplace bullying.
van Heugten, Kate
2013-03-01
The problem of workplace bullying appears to be especially common in the hospitality industry and in health, education, and social services. Bullying results in negative effects on the psychological and physical health and well-being of targets, bystanders, and those accused of bullying. I undertook a qualitative research project to investigate the experiences of 17 New Zealand social workers who identified themselves as having been targets of workplace bullying. All participants had experienced negative physical and psychological health impacts. I also found, however, that in the aftermath of their difficult experiences, most considered that they had eventually developed greater resilience. Resilience was enhanced when participants' sense of control over their situation improved and when they received support from witnesses and managers. I make recommendations to indicate how these resilience-promoting conditions can be achieved in the organizational setting.
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Murphy, Patrick C.
1999-01-01
This paper highlights some of the results and issues associated with estimating models to evaluate control law design methods and design criteria for advanced high performance aircraft. Experimental fighter aircraft such as the NASA High Alpha Research Vehicle (HARV) have the capability to maneuver at very high angles of attack where nonlinear aerodynamics often predominate. HARV is an experimental F/A-18, configured with thrust vectoring and conformal actuated nose strakes. Identifying closed-loop models for this type of aircraft can be made difficult by nonlinearities and high-order characteristics of the system. In this paper only lateral-directional axes are considered since the lateral-directional control law was specifically designed to produce classical airplane responses normally expected with low-order, rigid-body systems. Evaluation of the control design methodology was made using low-order equivalent systems determined from flight and simulation. This allowed comparison of the closed-loop rigid-body dynamics achieved in flight with that designed in simulation. In flight, the On Board Excitation System was used to apply optimal inputs to lateral stick and pedals at five angles of attack: 5, 20, 30, 45, and 60 degrees. Data analysis and closed-loop model identification were done using frequency domain maximum likelihood. The structure of the identified models was a linear state-space model reflecting classical 4th-order airplane dynamics. Input time delays associated with the high-order controller and aircraft system were accounted for in data preprocessing. A comparison of flight estimated models with small perturbation linear design models highlighted nonlinearities in the system and indicated that the estimated closed-loop rigid-body dynamics were sensitive to input amplitudes at 20 and 30 degrees angle of attack.
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Resiliency and subjective health assessment. Moderating role of selected psychosocial variables
Directory of Open Access Journals (Sweden)
Michalina Sołtys
2015-12-01
Full Text Available Background Resiliency is defined as a relatively permanent personality trait, which may be assigned to the category of health resources. The aim of this study was to determine conditions in which resiliency poses a significant health resource (moderation, thereby broadening knowledge of the specifics of the relationship between resiliency and subjective health assessment. Participants and procedure The study included 142 individuals. In order to examine the level of resiliency, the Assessment Resiliency Scale (SPP-25 by N. Ogińska-Bulik and Z. Juczyński was used. Participants evaluated subjective health state by means of an analogue-visual scale. Additionally, in the research the following moderating variables were controlled: sex, objective health status, having a partner, professional activity and age. These data were obtained by personal survey. Results The results confirmed the relationship between resiliency and subjective health assessment. Multiple regression analysis revealed that sex, having a partner and professional activity are significant moderators of associations between level of resiliency and subjective health evaluation. However, statistically significant interaction effects for health status and age as a moderator were not observed. Conclusions Resiliency is associated with subjective health assessment among adults, and selected socio-demographic features (such as sex, having a partner, professional activity moderate this relationship. This confirms the significant role of resiliency as a health resource and a reason to emphasize the benefits of enhancing the potential of individuals for their psychophysical wellbeing. However, the research requires replication in a more homogeneous sample.
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Healthy aging persons and their brains: promoting resilience through creative engagement.
McFadden, Susan H; Basting, Anne D
2010-02-01
Creative engagement, as an expression of and a support for resilience, may have a neuroprotective effect among older adults, contributing to retention of cognitive capacity. Recent research on creative activities shows that they strengthen social networks and give persons a sense of control; both outcomes have been associated with brain health. The authors cite evidence suggesting that positive social interactions can nurture resilience and creative engagement among older persons, including those living with dementia. The motivational, attentional, affective, and social components of creative activities combine to offer older persons meaningful opportunities to express and strengthen their resilience, regardless of their cognitive status, despite the biopsychosocial challenges of aging. The article addresses implications for future research, clinical practice, and public policy, and suggests how gaps in current research on resilience and creativity might be addressed.
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Optimization Based Clearance of Flight Control Laws A Civil Aircraft Application
Hansson, Anders; Puyou, Guilhem
2012-01-01
This book summarizes the main achievements of the EC funded 6th Framework Program project COFCLUO – Clearance of Flight Control Laws Using Optimization. This project successfully contributed to the achievement of a top-level objective to meet society’s needs for a more efficient, safer and environmentally friendly air transport by providing new techniques and tools for the clearance of flight control laws. This is an important part of the certification and qualification process of an aircraft – a costly and time-consuming process for the aeronautical industry. The overall objective of the COFCLUO project was to develop and apply optimization techniques to the clearance of flight control laws in order to improve efficiency and reliability. In the book, the new techniques are explained and benchmarked against traditional techniques currently used by the industry. The new techniques build on mathematical criteria derived from the certification and qualification requirements together with suitable models...
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Improving the Earthquake Resilience of Buildings The worst case approach
Takewaki, Izuru; Fujita, Kohei
2013-01-01
Engineers are always interested in the worst-case scenario. One of the most important and challenging missions of structural engineers may be to narrow the range of unexpected incidents in building structural design. Redundancy, robustness and resilience play an important role in such circumstances. Improving the Earthquake Resilience of Buildings: The worst case approach discusses the importance of worst-scenario approach for improved earthquake resilience of buildings and nuclear reactor facilities. Improving the Earthquake Resilience of Buildings: The worst case approach consists of two parts. The first part deals with the characterization and modeling of worst or critical ground motions on inelastic structures and the related worst-case scenario in the structural design of ordinary simple building structures. The second part of the book focuses on investigating the worst-case scenario for passively controlled and base-isolated buildings. This allows for detailed consideration of a range of topics includin...
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Happer, Kaitlin; Brown, Elissa J; Sharma-Patel, Komal
2017-11-01
Resilience, which is associated with relatively positive outcomes following negative life experiences, is an important research target in the field of child maltreatment (Luthar et al., 2000). The extant literature contains multiple conceptualizations of resilience, which hinders development in research and clinical utility. Three models emerge from the literature: resilience as an immediate outcome (i.e., behavioral or symptom response), resilience as a trait, and resilience as a dynamic process. The current study compared these models in youth undergoing trauma-specific cognitive behavioral therapy. Results provide the most support for resilience as a process, in which increase in resilience preceded associated decrease in posttraumatic stress and depressive symptoms. There was partial support for resilience conceptualized as an outcome, and minimal support for resilience as a trait. Results of the models are compared and discussed in the context of existing literature and in light of potential clinical implications for maltreated youth seeking treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
V. V. Erokhin
2015-01-01
Full Text Available Algorithms of determination of coordinates of the aircraft in the integrated system of navigation and optimum control of a trajectory are considered. Results of researches of parameters of a navigation session and precision characteristics of an assessment of location showed that application of optimum control of a trajectory allowув to increase the accuracy of navigation definitions in case of incomplete constellation of navigation satellites.
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Coral Reef Resilience, Tipping Points and the Strength of Herbivory.
Holbrook, Sally J; Schmitt, Russell J; Adam, Thomas C; Brooks, Andrew J
2016-11-02
Coral reefs increasingly are undergoing transitions from coral to macroalgal dominance. Although the functional roles of reef herbivores in controlling algae are becoming better understood, identifying possible tipping points in the herbivory-macroalgae relationships has remained a challenge. Assessment of where any coral reef ecosystem lies in relation to the coral-to-macroalgae tipping point is fundamental to understanding resilience properties, forecasting state shifts, and developing effective management practices. We conducted a multi-year field experiment in Moorea, French Polynesia to estimate these properties. While we found a sharp herbivory threshold where macroalgae escape control, ambient levels of herbivory by reef fishes were well above that needed to prevent proliferation of macroalgae. These findings are consistent with previously observed high resilience of the fore reef in Moorea. Our approach can identify vulnerable coral reef systems in urgent need of management action to both forestall shifts to macroalgae and preserve properties essential for resilience.
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Troudet, T.; Garg, S.; Merrill, W.
1992-01-01
The design of a dynamic neurocontroller with good robustness properties is presented for a multivariable aircraft control problem. The internal dynamics of the neurocontroller are synthesized by a state estimator feedback loop. The neurocontrol is generated by a multilayer feedforward neural network which is trained through backpropagation to minimize an objective function that is a weighted sum of tracking errors, and control input commands and rates. The neurocontroller exhibits good robustness through stability margins in phase and vehicle output gains. By maintaining performance and stability in the presence of sensor failures in the error loops, the structure of the neurocontroller is also consistent with the classical approach of flight control design.
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Resiliência e maus-tratos à criança Resilience and child abuse
Directory of Open Access Journals (Sweden)
Maria de Fátima Pinheiro da Silva Junqueira
2003-02-01
Full Text Available O artigo propõe discutir o conceito de resiliência a partir de uma revisão crítica. Foram priorizados textos produzidos por órgãos que têm um papel direcionador no campo da saúde da criança e do adolescente (OPAS - Organização Pan-Americana da Saúde; ASBRA - Associação Brasileira de Adolescência. Discute-se as principais definições de resiliência. São debatidas as contribuições e limitações das leituras vigentes. Debate-se ainda, as possibilidades conceituais e operativas da resiliência frente às situações de maus-tratos contra criança e adolescente, tomando o exemplo do abuso sexual intrafamiliar. Conclui-se que o conceito de resiliência apresenta polarizações em torno de certos eixos: "adaptação/superação", "inato/adquirido", "permanente/circunstancial". Contudo, ele aponta para um ponto comum: a singularidade e a delicadeza das relações microssociais de promoção em saúde.The article discusses the resilience concept from a critical review. It prioritizes texts produced by organizations with leading roles in the field of child and adolescent health (PAHO, Pan-American Health Organization; ASBRA, the Brazilian Association for Adolescence. The main definitions of resilience are discussed, along with a debate on the contributions and limitations of the current literature. Furthermore, the conceptual and operative possibilities of resilience when confronted with child abuse are discussed, specifically using intra-familial sexual abuse as an example. The authors conclude that the concept of resilience presents polarization around certain axes: "adaptation/overcoming process", "innate/acquired", "permanent/circumstantial". However, they all point to a common ground: the singularity and delicacy of micro-social health-promoting relationships.
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Brendtro, Larry K.; Longhurst, James E.
2005-01-01
Brain research opens new frontiers in working with children and youth experiencing conflict in school and community. Blending this knowledge with resilience science offers a roadmap for reclaiming those identified as "at risk." This article applies findings from resilience research and recent brain research to identify strategies for reaching…
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Predicting Health Resilience in Pediatric Type 1 Diabetes: A Test of the Resilience Model Framework.
Rohan, Jennifer M; Huang, Bin; Pendley, Jennifer Shroff; Delamater, Alan; Dolan, Lawrence; Reeves, Grafton; Drotar, Dennis
2015-10-01
This research examined whether individual and family-level factors during the transition from late childhood to early adolescence protected individuals from an increased risk of poor glycemic control across time, which is a predictor of future diabetes-related complications (i.e., health resilience). This longitudinal, multisite study included 239 patients with type 1 diabetes and their caregivers. Glycemic control was based on hemoglobin A1c. Individual and family-level factors included: demographic variables, youth behavioral regulation, adherence (frequency of blood glucose monitoring), diabetes self-management, level of parental support for diabetes autonomy, level of youth mastery and responsibility for diabetes management, and diabetes-related family conflict. Longitudinal mixed-effects logistic regression indicated that testing blood glucose more frequently, better self-management, and less diabetes-related family conflict were indicators of health resilience. Multiple individual and family-level factors predicted risk for future health complications. Future research should develop interventions targeting specific individual and family-level factors to sustain glycemic control within recommended targets, which reduces the risk of developing future health complications during the transition to adolescence and adulthood. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Different roles in the quest for system resilience.
Borges, Fábio Morais; Menegon, Nilton Luiz
2012-01-01
Into dangerous and complex systems with high degree of interactivity between its components, the variability is present at all time, demanding a high degree of control of its operation. Maintaining or recovering the normality, when the system is under some stress (instability) is a function of Resilience. To cope with prevention, forecast, recovery and with memory of experiences from learned lessons requires some features from the companies. This paper purposes a structure that enables the Total Resilience of a system production that defines the assignments for Workers, Designers and Management Team, according to its features and possibilities. During one year and a half developing studies on ergonomics area of a Brazilian Oil Refinery, several situations were observed and studied using Work Ergonomic Analysis. These situations show actions and strategies that workers use to maintain the system stability. Furthermore, they revealed the importance that these actions are stored in a database of learned lessons from the Company. The research resulted in a broad scheme. It places each of these groups in the process of Total Resilience. It also shows the human like a center of actions that ensure the continuity of the system, main element at Resilience (Anthropocentric View).
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Dias, Rachel; Santos, Raquel Luiza; Sousa, Maria Fernanda Barroso de; Nogueira, Marcela Moreira Lima; Torres, Bianca; Belfort, Tatiana; Dourado, Marcia Cristina Nascimento
2015-01-01
Although caregivers of people with dementia may face difficulties, some positive feelings of caregiving may be associated with resilience. This study systematically reviewed the definitions, methodological approaches and determinant models associated with resilience among caregivers of people with dementia. Search for articles published between 2003 and 2014 in ISI, PubMed/MEDLINE, SciELO and Lilacs using the search terms resilience, caregivers and dementia. Resilience has been defined as positive adaptation to face adversity, flexibility, psychological well-being, strength, healthy life, burden, social network and satisfaction with social support. No consensus was found about the definition of resilience associated with dementia. We classified the determinant variables into biological, psychological and social models. Higher levels of resilience were associated with lower depression rates and greater physical health. Other biological factors associated with higher levels of resilience were older age, African-American ethnicity and female sex. Lower burden, stress, neuroticism and perceived control were the main psychological factors associated with resilience. Social support was a moderating factor of resilience, and different types of support seemed to relieve the physical and mental overload caused by stress.
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Energy and Economic Trade Offs for Advanced Technology Subsonic Aircraft
Maddalon, D. V.; Wagner, R. D.
1976-01-01
Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Composite materials may raise aspect radio to about 11 to 12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.
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Coutu, Diane L.
2002-01-01
Looks at coping skills that carry people through life and why some have them and others do not. Suggests that resilience is a reflex, a way of facing and understanding the world, and that resilient people and companies face reality with staunchness, make meaning out of hardship, and improvise. (JOW)
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Directory of Open Access Journals (Sweden)
Diana-Maria Drigă
2015-12-01
Full Text Available The concept of resilience has represented during the recent years a leading concern both in Romania, within the European Union and worldwide. Specialists in economics, management, finance, legal sciences, political sciences, sociology, psychology, grant a particular interest to this concept. Multidisciplinary research of resilience has materialized throughout the time in multiple conceptualizations and theorizing, but without being a consensus between specialists in terms of content, specificity and scope. Through this paper it is intended to clarify the concept of resilience, achieving an exploration of the evolution of this concept in ecological, social and economic environment. At the same time, the paper presents aspects of feedback mechanisms and proposes a formalization of resilience using the logic and mathematical analysis.
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Directory of Open Access Journals (Sweden)
Clare Samantha Rees
2015-02-01
Full Text Available When not managed effectively, high levels of workplace stress can lead to several negative personal and performance outcomes. Some professional groups work in highly stressful settings and are therefore particularly at risk of conditions such as anxiety, depression, secondary traumatic stress and burnout. However, some individuals are less affected by workplace stress and the associated negative outcomes. Such individuals have been described as ‘resilient’. A number of studies have found relationships between levels of individual resilience and specific negative outcomes such as burnout and compassion fatigue. However, because psychological resilience is a multi-dimensional construct it is necessary to more clearly delineate it from other related and overlapping constructs. The creation of a testable theoretical model of individual workforce resilience, which includes both stable traits (e.g. neuroticism as well as more malleable intrapersonal factors (e.g. coping style, enables information to be derived that can eventually inform interventions aimed at enhancing individual resilience in the workplace. The purpose of this paper is to introduce a new theoretical model of individual workforce resilience that includes several intrapersonal constructs known to be central in the appraisal of and response to stressors and that also overlap with the construct of psychological resilience. We propose a model in which psychological resilience is hypothesised to mediate the relationship between neuroticism, mindfulness, self-efficacy, coping and psychological adjustment.
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Introduction 'Governance for Drought Resilience'
Bressers, Nanny; Bressers, Johannes T.A.; Larrue, Corinne; Bressers, Hans; Bressers, Nanny; Larrue, Corinne
2016-01-01
This book is about governance for drought resilience. But that simple sentence alone might rouse several questions. Because what do we mean with drought, and how does that relate to water scarcity? And what do we mean with resilience, and why is resilience needed for tackling drought? And how does
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Resiliency against stress among athletes
Directory of Open Access Journals (Sweden)
Kamila Litwic-Kaminska
2015-10-01
Full Text Available Background The aim of this paper is to describe the results of a study concerning the relationship between resiliency and appraisal of a stressful situation, anxiety reactions and undertaken methods of coping among sportsmen. Participants and procedure The research concerned 192 competitors who actively train in one of the Olympic disciplines – individual or team. We used the following instruments: Resiliency Assessment Scale (SPP-25; Stress Appraisal Questionnaire A/B; Reactions to Competition Questionnaire; Coping Inventory for Stressful Situations (CISS; Sport Stress Coping Strategies Questionnaire (SR3S, self-constructed. Results Athletes most frequently apply positive types of stress appraisal, and they cope with stress through a task-oriented style during competitions. There is a relationship between the level of resiliency and the analysed aspects of the process of stress. The higher the resiliency, the more positive is the appraisal of a stressful situation and the more task-oriented are the strategies applied. Similarly, in everyday situations resilient sportspeople positively appraise difficult situations and undertake mostly task-oriented strategies. Resiliency is connected with less frequently experiencing reactions in the form of anxiety. Conclusions The obtained results, similarly to previous research, suggest that resiliency is connected with experiencing positive emotions. It causes more frequent appraisal of stressful situations as a challenge. More resilient people also choose more effective and situation-appropriate coping strategies. Therefore they are more resistant to stress.
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Hospital nurses' lived experiences of intelligent resilience: a phenomenological study.
Imani, Behzad; Kermanshahi, Sima Mohamad Khan; Vanaki, Zohreh; Kazemnejad Lili, Anoshiravan
2018-02-15
The aim of this study was to explore Iranian hospital nurses' lived experiences of intelligent resilience. Nurses do high levels of emotional work when fulfilling patients' and their family members' complex needs. Intelligent resilience can alleviate nurses' stress and enhance their endurance. This study was based on the Husserlian descriptive phenomenology. A purposive sample of ten hospital nurses was drawn from hospitals affiliated with Hamadan University of Medical Sciences, Hamadan, Iran. In-depth semi-structured interviews were held to collect data. The seven-step data analysis approach proposed by Colaizzi was used for the data analysis. In this study, the adherence to consolidated criteria for reporting qualitative guidelines has been followed. The participating hospital nurses' lived experiences of intelligent resilience came into four main themes of patience and wisdom, reverence, situational self-control, and appealing to religiosity. Each of the four main themes included two subthemes which were having peace and wise quietness, reverence for the patients, physicians and nurses, distancing themselves from stressful situations and displacing staff who cause stress, and the nurse's trust in God as well as the patient and his family's trust in God, respectively. Nurses with intelligent resilience are able to bring peace, reverence for others, and situational self-control to stressors thereby providing higher quality of care to their patients. Nurses work in unstable and stressful conditions. The findings of this study provide better understanding about the concept of nurses' intelligent resilience and its indicators and attributes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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Mean annual precipitation predicts primary production resistance and resilience to extreme drought.
Stuart-Haëntjens, Ellen; De Boeck, Hans J; Lemoine, Nathan P; Mänd, Pille; Kröel-Dulay, György; Schmidt, Inger K; Jentsch, Anke; Stampfli, Andreas; Anderegg, William R L; Bahn, Michael; Kreyling, Juergen; Wohlgemuth, Thomas; Lloret, Francisco; Classen, Aimée T; Gough, Christopher M; Smith, Melinda D
2018-04-27
Extreme drought is increasing in frequency and intensity in many regions globally, with uncertain consequences for the resistance and resilience of ecosystem functions, including primary production. Primary production resistance, the capacity to withstand change during extreme drought, and resilience, the degree to which production recovers, vary among and within ecosystem types, obscuring generalized patterns of ecological stability. Theory and many observations suggest forest production is more resistant but less resilient than grassland production to extreme drought; however, studies of production sensitivity to precipitation variability indicate that the processes controlling resistance and resilience may be influenced more by mean annual precipitation (MAP) than ecosystem type. Here, we conducted a global meta-analysis to investigate primary production resistance and resilience to extreme drought in 64 forests and grasslands across a broad MAP gradient. We found resistance to extreme drought was predicted by MAP; however, grasslands (positive) and forests (negative) exhibited opposing resilience relationships with MAP. Our findings indicate that common plant physiological mechanisms may determine grassland and forest resistance to extreme drought, whereas differences among plant residents in turnover time, plant architecture, and drought adaptive strategies likely underlie divergent resilience patterns. The low resistance and resilience of dry grasslands suggests that these ecosystems are the most vulnerable to extreme drought - a vulnerability that is expected to compound as extreme drought frequency increases in the future. Copyright © 2018. Published by Elsevier B.V.
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Comparison of resilience in adolescent survivors of brain tumors and healthy adolescents.
Chen, Chin-Mi; Chen, Yueh-Chih; Wong, Tai-Tong
2014-01-01
Resilience is essential for the psychological adjustment of adolescents experiencing difficulty. Comparing differences in resilience between adolescent survivors of brain tumors and healthy adolescents may help identify factors related to resilience in adolescents. The purpose of this study was to clarify how illness impacts the normative development of adolescent survivors of brain tumors by comparing them to healthy adolescents in terms of resilience and how it is affected by various health problems. This cross-sectional, case-control study used convenience sampling to recruit 13- to 18-year-old adolescent survivors of brain tumors and healthy adolescents matched by school level, gender, and living area. Data were collected by structured questionnaires. The sample included 60 adolescent survivors and 120 healthy adolescents. Participants in both groups were predominantly male adolescents (63.3%) and junior high school students (55%). The 2 groups did not differ significantly in resilience, but survivors without emotional problems had a higher mean resilience score than did healthy adolescents and survivors with emotional problems (F = 8.65, P adolescent survivors of brain tumors and healthy adolescents. In addition, the impact of emotional problems on resilience was more severe in brain tumor survivors than in healthy adolescents. Our results suggest that pediatric oncology nurses design interdisciplinary school-based interventions to reduce the impact of emotional problems on resilience in both healthy adolescents and those who survived brain tumors.
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Communal resilience: the Lebanese case
Directory of Open Access Journals (Sweden)
Eric BOUTIN
2015-07-01
Full Text Available In a turbulent and aggressive environment, organizations are subject to external events. They are sometimes destabilized and can disappear. This context explains the multiplication of works studying resilience of human organizations. Resilience is then defined as the ability of the organization studied to face an external shock.This paper proposes a state of the art of resilience concept and considers the interests of the transposition of the concept to the field of a territorial community. A case study will lead us to apply the concept of resilience to the Lebanese nation.
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Practical Leakage-Resilient Symmetric Cryptography
DEFF Research Database (Denmark)
Faust, Sebastian; Pietrzak, Krzysztof; Schipper, Joachim
2012-01-01
Leakage resilient cryptography attempts to incorporate side-channel leakage into the black-box security model and designs cryptographic schemes that are provably secure within it. Informally, a scheme is leakage-resilient if it remains secure even if an adversary learns a bounded amount of arbitr......Leakage resilient cryptography attempts to incorporate side-channel leakage into the black-box security model and designs cryptographic schemes that are provably secure within it. Informally, a scheme is leakage-resilient if it remains secure even if an adversary learns a bounded amount...
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Rivest, David; Lorente, Miren; Olivier, Alain; Messier, Christian
2013-10-01
Agroforestry is increasingly viewed as an effective means of maintaining or even increasing crop and tree productivity under climate change while promoting other ecosystem functions and services. This study focused on soil biochemical properties and resilience following disturbance within agroforestry and conventional agricultural systems and aimed to determine whether soil differences in terms of these biochemical properties and resilience would subsequently affect crop productivity under extreme soil water conditions. Two research sites that had been established on agricultural land were selected for this study. The first site included an 18-year-old windbreak, while the second site consisted in an 8-year-old tree-based intercropping system. In each site, soil samples were used for the determination of soil nutrient availability, microbial dynamics and microbial resilience to different wetting-drying perturbations and for a greenhouse pot experiment with wheat. Drying and flooding were selected as water stress treatments and compared to a control. These treatments were initiated at the beginning of the wheat anthesis period and maintained over 10 days. Trees contributed to increase soil nutrient pools, as evidenced by the higher extractable-P (both sites), and the higher total N and mineralizable N (tree-based intercropping site) found in the agroforestry compared to the conventional agricultural system. Metabolic quotient (qCO2) was lower in the agroforestry than in the conventional agricultural system, suggesting higher microbial substrate use efficiency in agroforestry systems. Microbial resilience was higher in the agroforestry soils compared to soils from the conventional agricultural system (windbreak site only). At the windbreak site, wheat growing in soils from agroforestry system exhibited higher aboveground biomass and number of grains per spike than in conventional agricultural system soils in the three water stress treatments. At the tree
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Li, Xiaoming; Harrison, Sayward E; Fairchild, Amanda J; Chi, Peilian; Zhao, Junfeng; Zhao, Guoxiang
2017-10-01
Global literature suggests that resilience-based interventions may yield improvements in psychosocial well-being for vulnerable children, but limited data are available regarding the efficacy of such interventions among children affected by parental HIV/AIDS. To evaluate initial efficacy of a multi-level resilience-based intervention among children affected by parental HIV/AIDS in China in improving children's psychosocial well-being and resilience-related outcomes. Seven hundred-ninety children, 6-17 years of age, were recruited from rural China. Children were either AIDS orphans or were living with one or two parents infected with HIV/AIDS. Children and primary caregivers were randomly assigned to participate in a 4-arm trial to evaluate the Child-Caregiver-Advocacy Resilience (ChildCARE) intervention. This resilience-based psychosocial intervention provides programming at three levels (child, caregiver, community). Survey data were collected at baseline, 6-months, and 12-months in order to examine efficacy of the child-only and child + caregiver arms in improving children's psychological resilience. Intervention groups displayed improvements in several resilience-related outcomes at 6- and 12-month follow-ups, including self-reported coping, hopefulness, emotional regulation, and self-control. The child-only intervention arm showed some fading of intervention effects by 12-months. Preliminary findings suggest that the ChildCARE intervention is efficacious in promoting psychosocial well-being of children affected by parental HIV/AIDS in rural China. Targeting both children and caregivers for psychosocial intervention may be effective in improving children's resilience. Additional evaluation and modifications, including the inclusion of booster sessions, should be considered to further strengthen the program. Copyright © 2017 Elsevier Ltd. All rights reserved.
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DEFF Research Database (Denmark)
Dalgaard-Nielsen, Anja; Schack, Patrick
2016-01-01
of resilience to militant Islamism in three Danish communities. It shows how families and trust-based networks, including local government, are the major sources of resilience, but also how punitive national policies and discourses work at cross purposes with resilience-building by reducing local actors......Building community resilience to violent extremism increasingly figures as a goal in national security strategies and debates. The exact meaning of resilience remains unclear, complicating an informed discussion of whom and what to support. This article presents findings from an explorative study...
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McCann, Terence V; Songprakun, Wallapa; Stephenson, John
2016-02-01
Caring for a person with a mental illness can have adverse effects on caregivers; however, little is known about how best to help such caregivers. The aim of the present study was to examine the efficacy of a cognitive behaviour therapy-guided self-help manual in increasing resilience in caregivers of individuals with depression, in comparison to caregivers who receive routine support only. A randomized, controlled trial was conducted, following CONSORT guidelines, with 54 caregivers allocated to parallel intervention (self-help manual) (n = 27) or control (standard support) (n = 27) groups. Resilience was assessed at baseline, post-test (week 8), and follow up (week 12). Intention-to-treat analyses were undertaken. Repeated-measures ANOVA indicated a significant difference in resilience scores between the three time points, showing a large effect. Pairwise comparisons between intervention and control groups indicated resilience to be significantly different between baseline and post-test, and between baseline and follow up, but not between post-test and follow up. Overall, the intervention group showed a slightly greater increase in resilience over time than the control group; however, the time-group interaction was not significant. Guided self-help is helpful in improving caregivers' resilience and could be used as an adjunct to the limited support provided to carers by mental health nurses and other clinicians. © 2016 Australian College of Mental Health Nurses Inc.
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Aligning Organizational Pathologies and Organizational Resilience Indicators
Directory of Open Access Journals (Sweden)
Manuel Morales Allende
2017-07-01
Full Text Available Developing resilient individuals, organizations and communities is a hot topic in the research agenda in Management, Ecology, Psychology or Engineering. Despite the number of works that focus on resilience is increasing, there is not completely agreed definition of resilience, neither an entirely formal and accepted framework. The cause may be the spread of research among different fields. In this paper, we focus on the study of organizational resilience with the aim of improving the level of resilience in organizations. We review the relation between viable and resilient organizations and their common properties. Based on these common properties, we defend the application of the Viable System Model (VSM to design resilient organizations. We also identify the organizational pathologies defined applying the VSM through resilience indicators. We conclude that an organization with any organizational pathology is not likely to be resilient because it does not fulfill the requirements of viable organizations.
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Directory of Open Access Journals (Sweden)
Buzwell Simone
2011-10-01
Full Text Available Abstract Background The concept of resilience has captured the imagination of researchers and policy makers over the past two decades. However, despite the ever growing body of resilience research, there is a paucity of relevant, comprehensive measurement tools. In this article, the development of a theoretically based, comprehensive multi-dimensional measure of resilience in adolescents is described. Methods Extensive literature review and focus groups with young people living with chronic illness informed the conceptual development of scales and items. Two sequential rounds of factor and scale analyses were undertaken to revise the conceptually developed scales using data collected from young people living with a chronic illness and a general population sample. Results The revised Adolescent Resilience Questionnaire comprises 93 items and 12 scales measuring resilience factors in the domains of self, family, peer, school and community. All scales have acceptable alpha coefficients. Revised scales closely reflect conceptually developed scales. Conclusions It is proposed that, with further psychometric testing, this new measure of resilience will provide researchers and clinicians with a comprehensive and developmentally appropriate instrument to measure a young person's capacity to achieve positive outcomes despite life stressors.
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Pfefferbaum, Rose L; Pfefferbaum, Betty; Van Horn, Richard L; Klomp, Richard W; Norris, Fran H; Reissman, Dori B
2013-01-01
Community resilience has emerged as a construct to support and foster healthy individual, family, and community adaptation to mass casualty incidents. The Communities Advancing Resilience Toolkit (CART) is a publicly available theory-based and evidence-informed community intervention designed to enhance community resilience by bringing stakeholders together to address community issues in a process that includes assessment, feedback, planning, and action. Tools include a field-tested community resilience survey and other assessment and analytical instruments. The CART process encourages public engagement in problem solving and the development and use of local assets to address community needs. CART recognizes 4 interrelated domains that contribute to community resilience: connection and caring, resources, transformative potential, and disaster management. The primary value of CART is its contribution to community participation, communication, self-awareness, cooperation, and critical reflection and its ability to stimulate analysis, collaboration, skill building, resource sharing, and purposeful action.
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Dynamic Damage Modeling for IRAC Simulations, Phase I
National Aeronautics and Space Administration — NASA's Integrated Resilient Aircraft Control (IRAC) Project, Preliminary Technical Plan Summary identifies several causal and contributing factors that can lead to...
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Small Aircraft Transportation System Higher Volume Operations Concept
Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.
2006-01-01
This document defines the Small Aircraft Transportation System (SATS) Higher Volume Operations concept. The general philosophy underlying this concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. This document also provides details for a number of off-nominal and emergency procedures which address situations that could be expected to occur in a future SCA. The details for this operational concept along with a description of candidate aircraft systems to support this concept are provided.
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Bole, Brian; Teubert, Christopher Allen; Cuong Chi, Quach; Hogge, Edward; Vazquez, Sixto; Goebel, Kai; George, Vachtsevanos
2013-01-01
Software-in-the-loop and Hardware-in-the-loop testing of failure prognostics and decision making tools for aircraft systems will facilitate more comprehensive and cost-effective testing than what is practical to conduct with flight tests. A framework is described for the offline recreation of dynamic loads on simulated or physical aircraft powertrain components based on a real-time simulation of airframe dynamics running on a flight simulator, an inner-loop flight control policy executed by either an autopilot routine or a human pilot, and a supervisory fault management control policy. The creation of an offline framework for verifying and validating supervisory failure prognostics and decision making routines is described for the example of battery charge depletion failure scenarios onboard a prototype electric unmanned aerial vehicle.
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Reconnecting Social and Ecological Resilience in Salmon Ecosystems
Directory of Open Access Journals (Sweden)
Daniel L. Bottom
2009-06-01
Full Text Available Fishery management programs designed to control Pacific salmon (Oncorhynchus spp. for optimum production have failed to prevent widespread fish population decline and have caused greater uncertainty for salmon, their ecosystems, and the people who depend upon them. In this special feature introduction, we explore several key attributes of ecosystem resilience that have been overlooked by traditional salmon management approaches. The dynamics of salmon ecosystems involve social-ecological interactions across multiple scales that create difficult mismatches with the many jurisdictions that manage fisheries and other natural resources. Of particular importance to ecosystem resilience are large-scale shifts in oceanic and climatic regimes or in global economic conditions that unpredictably alter social and ecological systems. Past management actions that did not account for such changes have undermined salmon population resilience and increased the risk of irreversible regime shifts in salmon ecosystems. Because salmon convey important provisioning, cultural, and supporting services to their local watersheds, widespread population decline has undermined both human well-being and ecosystem resilience. Strengthening resilience will require expanding habitat opportunities for salmon populations to express their maximum life-history variation. Such actions also may benefit the "response diversity" of local communities by expanding the opportunities for people to express diverse social and economic values. Reestablishing social-ecological connections in salmon ecosystems will provide important ecosystem services, including those that depend on clean water, ample stream flows, functional wetlands and floodplains, intact riparian systems, and abundant fish populations.
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Indian Academy of Sciences (India)
With the evolution of high performance modern aircraft and spiraling developmental and experimental costs, the importance of flight validated databases for flight control design applications and for flight simulators has increased significantly in the recent past. Ground-based and in-flight simulators are increasingly used not ...
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OPTIMAL TRAFFIC MANAGEMENT FOR AIRCRAFT APPROACHING THE AERODROME LANDING AREA
Directory of Open Access Journals (Sweden)
Igor B. Ivenin
2018-01-01
Full Text Available The research proposes a mathematical optimization approach of arriving aircraft traffic at the aerodrome zone. The airfield having two parallel runways, capable of operating independently of each other, is modeled. The incoming traffic of aircraft is described by a Poisson flow of random events. The arriving aircraft are distributed by the air traffic controller between two runways. There is one approach flight path for each runway. Both approach paths have a common starting point. Each approach path has a different length. The approach trajectories do not overlap. For each of the two approach procedures, the air traffic controller sets the average speed of the aircraft. The given model of airfield and airfield zone is considered as the two-channel system of mass service with refusals in service. Each of the two servicing units includes an approach trajectory, a glide path and a runway. The servicing unit can be in one of two states – free and busy. The probabilities of the states of the servicing units are described by the Kolmogorov system of differential equations. The number of refusals in service on the simulated time interval is used as criterion for assessment of mass service system quality of functioning. This quality of functioning criterion is described by an integral functional. The functions describing the distribution of aircraft flows between the runways, as well as the functions describing the average speed of the aircraft, are control parameters. The optimization problem consists in finding such values of the control parameters for which the value of the criterion functional is minimal. To solve the formulated optimization problem, the L.S. Pontryagin maximum principle is applied. The form of the Hamiltonian function and the conjugate system of differential equations is given. The structure of optimal control has been studied for two different cases of restrictions on the control of the distribution of incoming aircraft
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Resilience Design Patterns - A Structured Approach to Resilience at Extreme Scale (version 1.1)
Energy Technology Data Exchange (ETDEWEB)
Hukerikar, Saurabh [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Engelmann, Christian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2016-12-01
Reliability is a serious concern for future extreme-scale high-performance computing (HPC) systems. Projections based on the current generation of HPC systems and technology roadmaps suggest the prevalence of very high fault rates in future systems. The errors resulting from these faults will propagate and generate various kinds of failures, which may result in outcomes ranging from result corruptions to catastrophic application crashes. Therefore the resilience challenge for extreme-scale HPC systems requires management of various hardware and software technologies that are capable of handling a broad set of fault models at accelerated fault rates. Also, due to practical limits on power consumption in HPC systems future systems are likely to embrace innovative architectures, increasing the levels of hardware and software complexities. As a result the techniques that seek to improve resilience must navigate the complex trade-off space between resilience and the overheads to power consumption and performance. While the HPC community has developed various resilience solutions, application-level techniques as well as system-based solutions, the solution space of HPC resilience techniques remains fragmented. There are no formal methods and metrics to investigate and evaluate resilience holistically in HPC systems that consider impact scope, handling coverage, and performance & power efficiency across the system stack. Additionally, few of the current approaches are portable to newer architectures and software environments that will be deployed on future systems. In this document, we develop a structured approach to the management of HPC resilience using the concept of resilience-based design patterns. A design pattern is a general repeatable solution to a commonly occurring problem. We identify the commonly occurring problems and solutions used to deal with faults, errors and failures in HPC systems. Each established solution is described in the form of a pattern that
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Park, S H; Naliboff, B D; Shih, W; Presson, A P; Videlock, E J; Ju, T; Kilpatrick, L; Gupta, A; Mayer, E A; Chang, L
2018-01-01
Irritable bowel syndrome (IBS) is a stress-sensitive disorder associated with early adverse life events (EALs) and a dysregulated hypothalamic-pituitary-adrenal (HPA) axis. Resilience is the ability to recover and adapt positively to stress but has not been well studied in IBS. The aims of this study are to compare resilience in IBS and healthy controls (HCs) and to assess its relationships with IBS symptom severity, quality of life (QOL), EALs, and HPA axis response. Two hundred fifty-six subjects (154 IBS, 102 HCs) completed questionnaires for resilience (Connor-Davidson Resilience Scale [CD-RISC] and Brief Resilience Scale [BRS]), IBS symptoms, IBS-QOL, and EALs. Ninety-six of these subjects had serial serum adrenocorticotropic hormone (ACTH) and cortisol levels to exogenous corticotrophin-releasing hormone (CRH) and ACTH measured. The relationship between IBS status, resilience, and other variables of interest was assessed by regression analysis after adjusting for demographics and neuroticism, a predictor of resilience. Resilience was significantly lower in IBS compared to HCs (CD-RISC: 72.16±14.97 vs 77.32±12.73, P=.003; BRS: 3.29±0.87 vs 3.93±0.69, Presilience and IBS status for ACTH-stimulated cortisol response (P=.031); more resilient IBS subjects had lower cortisol response, and more resilient HCs had higher cortisol response. Lower resilience is associated with IBS status, worse IBS symptom severity, lower IBS-QOL, greater EALs, and stress hyperresponsiveness. © 2017 John Wiley & Sons Ltd.
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Integrating the Base of Aircraft Data (BADA) in CTAS Trajectory Synthesizer
Abramson, Michael; Ali, Kareem
2012-01-01
The Center-Terminal Radar Approach Control (TRACON) Automation System (CTAS), developed at NASA Ames Research Center for assisting controllers in the management and control of air traffic in the extended terminal area, supports the modeling of more than four hundred aircraft types. However, 90% of them are supported indirectly by mapping them to one of a relatively few aircraft types for which CTAS has detailed drag and engine thrust models. On the other hand, the Base of Aircraft Data (BADA), developed and maintained by Eurocontrol, supports more than 300 aircraft types, about one third of which are directly supported, i.e. they have validated performance data. All these data were made available for CTAS by integrating BADA version 3.8 into CTAS Trajectory Synthesizer (TS). Several validation tools were developed and used to validate the integrated code and to evaluate the accuracy of trajectory predictions generated using CTAS "native" and BADA Aircraft Performance Models (APM) comparing them with radar track data. Results of these comparisons indicate that the two models have different strengths and weaknesses. The BADA APM can improve the accuracy of CTAS predictions at least for some aircraft types, especially small aircraft, and for some flight phases, especially climb.
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Wartelsteiner, F; Mizuno, Y; Frajo-Apor, B; Kemmler, G; Pardeller, S; Sondermann, C; Welte, A; Fleischhacker, W W; Uchida, H; Hofer, A
2016-10-01
Improving quality of life (QoL) is an important objective in the treatment of schizophrenia. The aim of the current study was to examine to what extent resilience, self-esteem, hopelessness, and psychopathology are correlated with QoL. We recruited 52 out-patients diagnosed with schizophrenia according to DSM-IV criteria and 77 healthy control subjects from the general community. In patients, psychopathology was quantified by the Positive and Negative Syndrome Scale. The following scales were used in both patients and control subjects: the Berliner Lebensqualitätsprofil, the Resilience Scale, the Rosenberg Self-Esteem Scale, and the Beck Hopelessness Scale to assess QoL, resilience, self-esteem, and hopelessness respectively. Patients with schizophrenia presented with significantly less QoL, resilience, self-esteem, and hope compared to healthy control subjects. In patients, QoL correlated moderately with resilience, self-esteem, and hopelessness and weakly with symptoms. With respect to the latter, particularly depression and positive symptoms were negatively correlated with QoL. Our results highlight the complex nature of QoL in patients suffering from schizophrenia. They underscore that significant efforts are necessary to enhance resilience and self-esteem and to diminish hopelessness as well as affective and positive symptoms in patients with schizophrenia. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Directory of Open Access Journals (Sweden)
Rachel Dias
2015-03-01
Full Text Available Introduction: Although caregivers of people with dementia may face difficulties, some positive feelings of caregiving may be associated with resilience.Objective: This study systematically reviewed the definitions, methodological approaches and determinant models associated with resilience among caregivers of people with dementia.Methods: Search for articles published between 2003 and 2014 in ISI, PubMed/MEDLINE, SciELO and Lilacs using the search terms resilience, caregivers and dementia.Results and conclusions: Resilience has been defined as positive adaptation to face adversity, flexibility, psychological well-being, strength, healthy life, burden, social network and satisfaction with social support. No consensus was found about the definition of resilience associated with dementia. We classified the determinant variables into biological, psychological and social models. Higher levels of resilience were associated with lower depression rates and greater physical health. Other biological factors associated with higher levels of resilience were older age, African-American ethnicity and female sex. Lower burden, stress, neuroticism and perceived control were the main psychological factors associated with resilience. Social support was a moderating factor of resilience, and different types of support seemed to relieve the physical and mental overload caused by stress.
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Model-Based Control of an Aircraft Engine using an Optimal Tuner Approach
Connolly, Joseph W.; Chicatelli, Amy; Garg, Sanjay
2012-01-01
This paper covers the development of a model-based engine control (MBEC) method- ology applied to an aircraft turbofan engine. Here, a linear model extracted from the Commercial Modular Aero-Propulsion System Simulation 40,000 (CMAPSS40k) at a cruise operating point serves as the engine and the on-board model. The on-board model is up- dated using an optimal tuner Kalman Filter (OTKF) estimation routine, which enables the on-board model to self-tune to account for engine performance variations. The focus here is on developing a methodology for MBEC with direct control of estimated parameters of interest such as thrust and stall margins. MBEC provides the ability for a tighter control bound of thrust over the entire life cycle of the engine that is not achievable using traditional control feedback, which uses engine pressure ratio or fan speed. CMAPSS40k is capable of modeling realistic engine performance, allowing for a verification of the MBEC tighter thrust control. In addition, investigations of using the MBEC to provide a surge limit for the controller limit logic are presented that could provide benefits over a simple acceleration schedule that is currently used in engine control architectures.
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Beyond procedures: team reflection in a rail control centre to enhance resilience
Siegel, A.W.; Schraagen, Johannes Martinus Cornelis
2017-01-01
Resilience engineering concepts can complement proceduralization of complex sociotechnical systems (STS). Proceduralization aims at defining precise and quantified system objectives, and at defining a process that describes and prescribes how to achieve those objectives. Although proceduralization
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Beyond procedures : Team reflection in a rail control centre to enhance resilience
Siegel, A.W.; Schraagen, J.M.C.
2017-01-01
Resilience engineering concepts can complement proceduralization of complex sociotechnical systems (STS). Proceduralization aims at defining precise and quantified system objectives, and at defining a process that describes and prescribes how to achieve those objectives. Although proceduralization
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78 FR 67799 - Qualification, Service, and Use of Crewmembers and Aircraft Dispatchers
2013-11-12
... and aircraft dispatcher training reflects that integrated operating environment. Since the publication... control systems, and unusual attitudes that result from flight control malfunctions and uncommanded flight... manipulate the aircraft controls and flight navigators are no longer used in part 121 operations, the FAA...
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Frajo-Apor, Beatrice; Pardeller, Silvia; Kemmler, Georg; Hofer, Alex
2016-09-01
Emotional Intelligence (EI) and resilience may be considered as prerequisites for mental health professionals caring for patients with serious mental illness (SMI), since they are often exposed to severe emotional stress during daily work. Accordingly, this cross-sectional study assessed both EI and resilience and their interrelationship in 61 individuals belonging to an assertive outreach team for patients suffering from SMI compared 61 control subjects without healthcare-related working conditions. EI was assessed by means of the German version of the Mayer-Salovey-Caruso-Emotional-Intelligence Test (MSCEIT), resilience was assessed using the German version of the Resilience Scale. Both groups showed an average level of EI in all categories of the MSCEIT and indicated high levels of resilience. They did not differ significantly from each other, neither in terms of EI nor resilience. Correlation analysis revealed a positive association between EI and resilience, albeit small in magnitude. Our results suggest that mental health professionals are not more resilient and therefore not more 'protected' from stressors than the general population. Though this finding warrants cautious interpretation, the positive correlation between EI and resilience suggests that EI may be a potential target for education and training in order to strengthen resilience even in healthy individuals and vice versa.
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X-36 Tailless Fighter Agility Research Aircraft in flight
1997-01-01
The lack of a vertical tail on the X-36 technology demonstrator is evident as the remotely piloted aircraft flies a low-altitude research flight above Rogers Dry Lake at Edwards Air Force Base in the California desert on October 30, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three
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Reciprocal Relations Between Emotional Self-Efficacy Beliefs and Ego-Resiliency across Time
Milioni, Michela; Alessandri, Guido; Eisenberg, Nancy; Castellani, Valeria; Zuffianò, Antonio; Vecchione, Michele; Caprara, Gian Vittorio
2015-01-01
Objective The present study examined the longitudinal relations of adolescents’ self-reported ego-resiliency to their emotional self-efficacy beliefs in expressing positive emotions and in managing negative emotions as they moved into early adulthood. Method Participants were 239 females and 211 males with a mean age of 17 years (SD = .80) at T1, 19 years (SD = .80) at T2, 21 years (SD = .82) at T3, and 25 years (SD = .80) at T4. A four-wave cross-lagged regression model and mediational analyses were used. Results In a panel structural equation model controlling for the stability of the constructs, reciprocal relationships across time were found between ego-resiliency and emotional self-efficacy beliefs related to the expression of positive emotions and to the management of negative emotions. Moreover, the relation between ego-resiliency assessed at T1 and T3, and ego-resiliency assessed at T2 and T4 was mediated through emotional self-efficacy beliefs (at T2 and T3, respectively), and vice versa. Conclusions The posited conceptual model accounted for a significant portion of variance in ego-resiliency and has implications for understanding the development of ego-resiliency. PMID:25204666
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The Australian Natural Disaster Resilience Index
Thoms, Martin
2016-04-01
The Australian Natural Disaster Resilience Index Martin Thoms, Melissa Parsons, Phil Morley Bushfire and Natural Hazards Cooperative Research Centre, Geography and Planning, University of New England, Armidale NSW 2351, Australia. Natural hazard management policy directions in Australia - and indeed internationally - are increasingly being aligned to ideas of resilience. Resilience to natural hazards is the ability of individuals and communities to cope with disturbance and adversity and to maintain adaptive behaviour. Operationalizing the measurement and assessment of disaster resilience is often undertaken using a composite index, but this exercise is yet to be undertaken in Australia. The Australian Natural Disaster Resilience Index is a top-down, national scale assessment of the resilience of communities to natural hazards. Resilience is assessed based on two sets of capacities: coping and adaptive capacities. Coping capacity relates to the factors influencing the ability of a community to prepare for, absorb and recover from a natural hazard event. Adaptive capacity relates to the arrangements and processes that enable adjustment through learning, adaptation and transformation. Indicators are derived under themes of social character, economic capital, infrastructure and planning, emergency services, community capital, information and engagement and governance/leadership/policy, using existing data sets (e.g. census data) or evaluation of policy and procedure (e.g. disaster management planning). A composite index of disaster resilience is then computed for each spatial division, giving national scale coverage. The results of the Australian Natural Disaster Resilience Index will be reported in a State of Disaster Resilience report, due in 2018. The index is co-designed with emergency service agencies, and will support policy development, planning, community engagement and emergency management.
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[Perspectives on resilience : trait or aptitude ?
Rolin, H; Fossion, P; Kotsou, I; Leys, C
2018-01-01
In this paper, we discuss various issues related to the concept of resilience, which is conventionally defined as a dynamic process allowing for a positive adaptation in a context of significant adversity. First, we try to draw the reader's attention to the importance of the concept of resilience in terms of public health. Second, we address the difficulty of measuring resilience in a relevant and operational manner. Third, we then address the question of whether resilience can be conceived only in the context of a confrontation with trauma, or whether its application can be relevant to the everyday nontraumatic adversity. In this regard, we introduce and define another coping strategy which is the Sense of Coherence (SOC). Fourth, we discuss the nature of resilience, that is to say, whether it should be considered as a personality trait or as an aptitude. We try to show that this problem arises from the difficulty to specify the emotional processes involved in resilience. Finally, we propose future research perspectives that should allow us to better understand the concept of resilience.
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Development of Nonlinear Flight Mechanical Model of High Aspect Ratio Light Utility Aircraft
Bahri, S.; Sasongko, R. A.
2018-04-01
The implementation of Flight Control Law (FCL) for Aircraft Electronic Flight Control System (EFCS) aims to reduce pilot workload, while can also enhance the control performance during missions that require long endurance flight and high accuracy maneuver. In the development of FCL, a quantitative representation of the aircraft dynamics is needed for describing the aircraft dynamics characteristic and for becoming the basis of the FCL design. Hence, a 6 Degree of Freedom nonlinear model of a light utility aircraft dynamics, also called the nonlinear Flight Mechanical Model (FMM), is constructed. This paper shows the construction of FMM from mathematical formulation, the architecture design of FMM, the trimming process and simulations. The verification of FMM is done by analysis of aircraft behaviour in selected trimmed conditions.
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NDE of Damage in Aircraft Flight Control Surfaces
International Nuclear Information System (INIS)
Hsu, David K.; Barnard, Daniel J.; Dayal, Vinay
2007-01-01
Flight control surfaces on an aircraft, such as ailerons, flaps, spoilers and rudders, are typically adhesively bonded composite or aluminum honeycomb sandwich structures. These components can suffer from damage caused by hail stone, runway debris, or dropped tools during maintenance. On composites, low velocity impact damages can escape visual inspection, whereas on aluminum honeycomb sandwich, budding failure of the honeycomb core may or may not be accompanied by a disbond. This paper reports a study of the damage morphology in such structures and the NDE methods for detecting and characterizing them. Impact damages or overload failures in composite sandwiches with Nomex or fiberglass core tend to be a fracture or crinkle or the honeycomb cell wall located a distance below the facesheet-to-core bondline. The damage in aluminum honeycomb is usually a buckling failure, propagating from the top skin downward. The NDE methods used in this work for mapping out these damages were: air-coupled ultrasonic scan, and imaging by computer aided tap tester. Representative results obtained from the field will be shown
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Hydropower and sustainability: resilience and vulnerability in China's powersheds.
McNally, Amy; Magee, Darrin; Wolf, Aaron T
2009-07-01
Large dams represent a whole complex of social, economic and ecological processes, perhaps more than any other large infrastructure project. Today, countries with rapidly developing economies are constructing new dams to provide energy and flood control to growing populations in riparian and distant urban communities. If the system is lacking institutional capacity to absorb these physical and institutional changes there is potential for conflict, thereby threatening human security. In this paper, we propose analyzing sustainability (political, socioeconomic, and ecological) in terms of resilience versus vulnerability, framed within the spatial abstraction of a powershed. The powershed framework facilitates multi-scalar and transboundary analysis while remaining focused on the questions of resilience and vulnerability relating to hydropower dams. Focusing on examples from China, this paper describes the complex nature of dams using the sustainability and powershed frameworks. We then analyze the roles of institutions in China to understand the relationships between power, human security and the socio-ecological system. To inform the study of conflicts over dams China is a particularly useful case study because we can examine what happens at the international, national and local scales. The powershed perspective allows us to examine resilience and vulnerability across political boundaries from a dynamic, process-defined analytical scale while remaining focused on a host of questions relating to hydro-development that invoke drivers and impacts on national and sub-national scales. The ability to disaggregate the affects of hydropower dam construction from political boundaries allows for a deeper analysis of resilience and vulnerability. From our analysis we find that reforms in China's hydropower sector since 1996 have been motivated by the need to create stability at the national scale rather than resilient solutions to China's growing demand for energy and water
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Resilience in women with autoimmune rheumatic diseases.
Rojas, Manuel; Rodriguez, Yhojan; Pacheco, Yovana; Zapata, Elizabeth; Monsalve, Diana M; Mantilla, Rubén D; Rodríguez-Jimenez, Monica; Ramírez-Santana, Carolina; Molano-González, Nicolás; Anaya, Juan-Manuel
2017-12-28
To evaluate the relationship between resilience and clinical outcomes in patients with autoimmune rheumatic diseases. Focus groups, individual interviews, and chart reviews were done to collect data on 188 women with autoimmune rheumatic diseases, namely rheumatoid arthritis (n=51), systemic lupus erythematosus (n=70), systemic sclerosis (n=35), and Sjögren's syndrome (n=32). Demographic, clinical, and laboratory variables were assessed including disease activity by patient reported outcomes. Resilience was evaluated by using the Brief Resilience Scale. Bivariate, multiple linear regression, and classification and regression trees were used to analyse data. Resilience was influenced by age, duration of disease, and socioeconomic status. Lower resilience scores were observed in younger patients (50years) had higher resilience scores regardless of socioeconomic status. There was no influence of disease activity on resilience. A particular behaviour was observed in systemic sclerosis in which patients with high socioeconomic status and regular physical activity had higher resilience scores. Resilience in patients with autoimmune rheumatic diseases is a continuum process influenced by age and socioeconomic status. The ways in which these variables along with exercise influence resilience deserve further investigation. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.
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Resilience in Utility Technologies
Seaton, Roger
The following sections are included: * Scope of paper * Preamble * Background to the case-study projects * Source projects * Resilience * Case study 1: Electricity generation * Context * Model * Case study 2: Water recycling * Context * Model * Case study 3: Ecotechnology and water treatment * Context * The problem of classification: Finding a classificatory solution * Application of the new taxonomy to water treatment * Concluding comments and questions * Conclusions * Questions and issues * Purposive or Purposeful? * Resilience: Flexibility and adaptivity? * Resilience: With respect of what? * Risk, uncertainty, surprise, emergence - What sort of shock, and who says so? * Co-evolutionary friction * References
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Metrics required for Power System Resilient Operations and Protection
Energy Technology Data Exchange (ETDEWEB)
Eshghi, K.; Johnson, B. K.; Rieger, C. G.
2016-08-01
Today’s complex grid involves many interdependent systems. Various layers of hierarchical control and communication systems are coordinated, both spatially and temporally to achieve gird reliability. As new communication network based control system technologies are being deployed, the interconnected nature of these systems is becoming more complex. Deployment of smart grid concepts promises effective integration of renewable resources, especially if combined with energy storage. However, without a philosophical focus on resilience, a smart grid will potentially lead to higher magnitude and/or duration of disruptive events. The effectiveness of a resilient infrastructure depends upon its ability to anticipate, absorb, adapt to, and/or rapidly recover from a potentially catastrophic event. Future system operations can be enhanced with a resilient philosophy through architecting the complexity with state awareness metrics that recognize changing system conditions and provide for an agile and adaptive response. The starting point for metrics lies in first understanding the attributes of performance that will be qualified. In this paper, we will overview those attributes and describe how they will be characterized by designing a distributed agent that can be applied to the power grid.
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The impact of resilience and subsequent stressful life events on MDD and GAD.
Sheerin, Christina M; Lind, Mackenzie J; Brown, Emily A; Gardner, Charles O; Kendler, Kenneth S; Amstadter, Ananda B
2018-02-01
There remains a dearth of research examining the "buffering" effect of resilience, wherein resilience at one point in time would be expected to protect an individual against development of psychopathology following future adverse life events. Using longitudinal data from an epidemiological twin sample (N = 7463), this study tested whether resilience would act as a buffer for stressful life events (SLEs) against risk for major depressive disorder (MDD) and generalized anxiety disorder (GAD). Resilience, demographics, and psychopathology were measured at Time 1 and recent SLEs and current MDD and GAD were measured at Time 2. Final models, controlling for demographic covariates and Time 1 diagnosis, examined the impact of Time 1 resilience, recent SLEs, their interaction, and a three-way interaction adding sex on MDD and GAD. The pattern of findings was the same for MDD and GAD, wherein main effects and two-way interactions of resilience and SLEs were significant, such that greater resilience was protective even in the context of high numbers of past-year SLEs. The three-way interaction was not significant, suggesting that the relationship between SLEs and resilience on psychopathology was the same for both men and women. Findings support the conceptualization of resilience as a buffer against the impact of future life stressors on common internalizing psychopathology. Longitudinal designs and trajectory-based studies that include recurring measures of SLEs could inform conceptualizations of resilience in the context of ongoing adversity and aid in developing interventions aimed at fostering healthy adaptation in the face of stressors. © 2017 Wiley Periodicals, Inc.
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Intelligent Aircraft Damage Assessment, Trajectory Planning, and Decision-Making under Uncertainty
Lopez, Israel; Sarigul-Klijn, Nesrin
Situational awareness and learning are necessary to identify and select the optimal set of mutually non-exclusive hypothesis in order to maximize mission performance and adapt system behavior accordingly. This paper presents a hierarchical and decentralized approach for integrated damage assessment and trajectory planning in aircraft with uncertain navigational decision-making. Aircraft navigation can be safely accomplished by properly addressing the following: decision-making, obstacle perception, aircraft state estimation, and aircraft control. When in-flight failures or damage occur, rapid and precise decision-making under imprecise information is required in order to regain and maintain control of the aircraft. To achieve planned aircraft trajectory and complete safe landing, the uncertainties in system dynamics of the damaged aircraft need to be learned and incorporated at the level of motion planning. The damaged aircraft is simulated via a simplified kinematic model. The different sources and perspectives of uncertainties in the damage assessment process and post-failure trajectory planning are presented and classified. The decision-making process for an emergency motion planning and landing is developed via the Dempster-Shafer evidence theory. The objective of the trajectory planning is to arrive at a target position while maximizing the safety of the aircraft given uncertain conditions. Simulations are presented for an emergency motion planning and landing that takes into account aircraft dynamics, path complexity, distance to landing site, runway characteristics, and subjective human decision.
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Resilience in families in which a member has been diagnosed with schizophrenia.
Bishop, M; Greeff, A P
2015-09-01
Due to the extensive focus of the literature on the burden placed on families in which a member has been diagnosed with a mental illness such as schizophrenia, there is a need to identify factors that may help these families to be resilient and adapt to their crisis. The aim of this study was to identify family resilience qualities in families in which a member has been diagnosed with schizophrenia. The study comprised 42 families, represented by 33 parents and 9 siblings of the diagnosed family member. Families were recruited from three support groups within the Cape Metropolitan area, Western Cape, South Africa. Qualitative data were obtained through an open-ended question and quantitative data were collected with seven self-report questionnaires. The following family resilience qualities were identified: family income; finding support in their community; family togetherness; family communication style during crises; affirming and supportive communication patterns; family hardiness; commitment to the family; reframing crises as a challenge; and an internal locus of control within the family. The findings may be used by professionals and support group facilitators to enhance the resilience and functioning of families living with a member with schizophrenia. With approximately 1% of the world's population diagnosed with schizophrenia, it is clear that many families are affected when a member has been diagnosed. There is a need to identify factors that may help these families to be resilient. The aim of this study was to identify family resilience qualities in families in which a member has been diagnosed with schizophrenia. The following family resilience qualities were identified as resources that helped them to adapt to the many challenges put to them: family income, finding support in their community, the availability of hospitals, churches and professionals, family togetherness, family communication, family hardiness, commitment to the family, reframing crises
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Resilience definitions, theory, and challenges: interdisciplinary perspectives.
Southwick, Steven M; Bonanno, George A; Masten, Ann S; Panter-Brick, Catherine; Yehuda, Rachel
2014-01-01
In this paper, inspired by the plenary panel at the 2013 meeting of the International Society for Traumatic Stress Studies, Dr. Steven Southwick (chair) and multidisciplinary panelists Drs. George Bonanno, Ann Masten, Catherine Panter-Brick, and Rachel Yehuda tackle some of the most pressing current questions in the field of resilience research including: (1) how do we define resilience, (2) what are the most important determinants of resilience, (3) how are new technologies informing the science of resilience, and (4) what are the most effective ways to enhance resilience? These multidisciplinary experts provide insight into these difficult questions, and although each of the panelists had a slightly different definition of resilience, most of the proposed definitions included a concept of healthy, adaptive, or integrated positive functioning over the passage of time in the aftermath of adversity. The panelists agreed that resilience is a complex construct and it may be defined differently in the context of individuals, families, organizations, societies, and cultures. With regard to the determinants of resilience, there was a consensus that the empirical study of this construct needs to be approached from a multiple level of analysis perspective that includes genetic, epigenetic, developmental, demographic, cultural, economic, and social variables. The empirical study of determinates of resilience will inform efforts made at fostering resilience, with the recognition that resilience may be enhanced on numerous levels (e.g., individual, family, community, culture).
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Resilience definitions, theory, and challenges: interdisciplinary perspectives
Southwick, Steven M.; Bonanno, George A.; Masten, Ann S.; Panter-Brick, Catherine; Yehuda, Rachel
2014-01-01
In this paper, inspired by the plenary panel at the 2013 meeting of the International Society for Traumatic Stress Studies, Dr. Steven Southwick (chair) and multidisciplinary panelists Drs. George Bonanno, Ann Masten, Catherine Panter-Brick, and Rachel Yehuda tackle some of the most pressing current questions in the field of resilience research including: (1) how do we define resilience, (2) what are the most important determinants of resilience, (3) how are new technologies informing the science of resilience, and (4) what are the most effective ways to enhance resilience? These multidisciplinary experts provide insight into these difficult questions, and although each of the panelists had a slightly different definition of resilience, most of the proposed definitions included a concept of healthy, adaptive, or integrated positive functioning over the passage of time in the aftermath of adversity. The panelists agreed that resilience is a complex construct and it may be defined differently in the context of individuals, families, organizations, societies, and cultures. With regard to the determinants of resilience, there was a consensus that the empirical study of this construct needs to be approached from a multiple level of analysis perspective that includes genetic, epigenetic, developmental, demographic, cultural, economic, and social variables. The empirical study of determinates of resilience will inform efforts made at fostering resilience, with the recognition that resilience may be enhanced on numerous levels (e.g., individual, family, community, culture). PMID:25317257
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Transdisciplinary application of the cross-scale resilience model
Sundstrom, Shana M.; Angeler, David G.; Garmestani, Ahjond S.; Garcia, Jorge H.; Allen, Craig R.
2014-01-01
The cross-scale resilience model was developed in ecology to explain the emergence of resilience from the distribution of ecological functions within and across scales, and as a tool to assess resilience. We propose that the model and the underlying discontinuity hypothesis are relevant to other complex adaptive systems, and can be used to identify and track changes in system parameters related to resilience. We explain the theory behind the cross-scale resilience model, review the cases where it has been applied to non-ecological systems, and discuss some examples of social-ecological, archaeological/ anthropological, and economic systems where a cross-scale resilience analysis could add a quantitative dimension to our current understanding of system dynamics and resilience. We argue that the scaling and diversity parameters suitable for a resilience analysis of ecological systems are appropriate for a broad suite of systems where non-normative quantitative assessments of resilience are desired. Our planet is currently characterized by fast environmental and social change, and the cross-scale resilience model has the potential to quantify resilience across many types of complex adaptive systems.
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Fast Aircraft Turnaround Enabled by Reliable Passenger Boarding
Directory of Open Access Journals (Sweden)
Michael Schultz
2018-01-01
Full Text Available Future 4D aircraft trajectories demand comprehensive consideration of environmental, economic, and operational constraints, as well as reliable prediction of all aircraft-related processes. Mutual interdependencies between airports result in system-wide, far-reaching effects in the air traffic network (reactionary delays. To comply with airline/airport challenges over the day of operations, a change to an air-to-air perspective is necessary, with a specific focus on the aircraft ground operations as major driver for airline punctuality. Aircraft ground trajectories primarily consists of handling processes at the stand (deboarding, catering, fueling, cleaning, boarding, unloading, loading, which are defined as the aircraft turnaround. Turnaround processes are mainly controlled by ground handling, airport, or airline staff, except the aircraft boarding, which is driven by passengers’ experience and willingness/ability to follow the proposed boarding procedures. This paper provides an overview of the research done in the field of aircraft boarding and introduces a reliable, calibrated, and stochastic aircraft boarding model. The stochastic boarding model is implemented in a simulation environment to evaluate specific boarding scenarios using different boarding strategies and innovative technologies. Furthermore, the potential of a connected aircraft cabin as sensor network is emphasized, which could provide information on the current and future status of the boarding process.
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Diehl, Manfred; Hay, Elizabeth L.
2010-01-01
This study observed young, middle-aged, and older adults (N = 239; M[subscript age] = 49.6 years; range = 18-89 years) for 30 consecutive days to examine the association between daily stress and negative affect, taking into account potential risk (i.e., self-concept incoherence) and resilience (i.e., age, perceived personal control) factors.…
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Weed detection using unmanned aircraft vehicles
Directory of Open Access Journals (Sweden)
Pflanz, Michael
2014-03-01
Full Text Available In contrast to agricultural remote sensing technologies, which are based on images from satellites or manned aircrafts, photogrammetry at low altitude from unmanned aircraft vehicles lead to higher spatial resolution, real-time processing and lower costs. Moreover multicopter aircrafts are suitable vehicles to perform precise path or stationary flights. In terms of vegetation photogrammetry this minimises motion blur and provide better image overlapping for stitching and mapping procedures. Through improved image analyses and through the recent increase in the availability of powerful batteries, microcontrollers and multispectral cameras, it can be expected in future that spatial mapping of weeds from low altitudes will be promoted. A small unmanned aircraft vehicle with a modified RGB camera was tested taking images from agricultural fields. A microcopter with six rotors was applied. The hexacopter in particular is GPS controlled and operates within predefined areas at given altitudes (from 5 to 10 m. Different scenarios of photogrammetrically weed detection have been carried out regarding to variable altitude, image resolution, weed and crop growth stages. First experiences with microcopter showed a high potential for site-specific weed control. Images analyses with regards to recognition of weed patches can be used to adapt herbicide applications to varying weed occurrence across a field.
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EPA is proposing to adopt emission standards and related provisions for aircraft gas turbine engines with rated thrusts greater than 26.7 kilonewtons. These engines are used primarily on commercial passenger and freight aircraft.
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Kirkland, James L; Stout, Michael B; Sierra, Felipe
2016-11-01
Recently discovered interventions that target fundamental aging mechanisms have been shown to increase life span in mice and other species, and in some cases, these same manipulations have been shown to enhance health span and alleviate multiple age-related diseases and conditions. Aging is generally associated with decreases in resilience, the capacity to respond to or recover from clinically relevant stresses such as surgery, infections, or vascular events. We hypothesize that the age-related increase in susceptibility to those diseases and conditions is driven by or associated with the decrease in resilience. Thus, a test for resilience at middle age or even earlier could represent a surrogate approach to test the hypothesis that an intervention delays the process of aging itself. For this, animal models to test resilience accurately and predictably are needed. In addition, interventions that increase resilience might lead to treatments aimed at enhancing recovery following acute illnesses, or preventing poor outcomes from medical interventions in older, prefrail subjects. At a meeting of basic researchers and clinicians engaged in research on mechanisms of aging and care of the elderly, the merits and drawbacks of investigating effects of interventions on resilience in mice were considered. Available and potential stressors for assessing physiological resilience as well as the notion of developing a limited battery of such stressors and how to rank them were discussed. Relevant ranking parameters included value in assessing general health (as opposed to focusing on a single physiological system), ease of use, cost, reproducibility, clinical relevance, and feasibility of being repeated in the same animal longitudinally. During the discussions it became clear that, while this is an important area, very little is known or established. Much more research is needed in the near future to develop appropriate tests of resilience in animal models within an aging context
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Pilot Critical Incident Reports as a Means to Identify Human Factors of Remotely Piloted Aircraft
Hobbs, Alan; Cardoza, Colleen; Null, Cynthia
2016-01-01
It has been estimated that aviation accidents are typically preceded by numerous minor incidents arising from the same causal factors that ultimately produced the accident. Accident databases provide in-depth information on a relatively small number of occurrences, however incident databases have the potential to provide insights into the human factors of Remotely Piloted Aircraft System (RPAS) operations based on a larger volume of less-detailed reports. Currently, there is a lack of incident data dealing with the human factors of unmanned aircraft systems. An exploratory study is being conducted to examine the feasibility of collecting voluntary critical incident reports from RPAS pilots. Twenty-three experienced RPAS pilots volunteered to participate in focus groups in which they described critical incidents from their own experience. Participants were asked to recall (1) incidents that revealed a system flaw, or (2) highlighted a case where the human operator contributed to system resilience or mission success. Participants were asked to only report incidents that could be included in a public document. During each focus group session, a note taker produced a de-identified written record of the incident narratives. At the end of the session, participants reviewed each written incident report, and made edits and corrections as necessary. The incidents were later analyzed to identify contributing factors, with a focus on design issues that either hindered or assisted the pilot during the events. A total of 90 incidents were reported. Human factor issues included the impact of reduced sensory cues, traffic separation in the absence of an out-the-window view, control latencies, vigilance during monotonous and ultra-long endurance flights, control station design considerations, transfer of control between control stations, the management of lost link procedures, and decision-making during emergencies. Pilots participated willingly and enthusiastically in the study
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Personality Strengths as Resilience: A One-Year Multiwave Study.
Goodman, Fallon R; Disabato, David J; Kashdan, Todd B; Machell, Kyla A
2017-06-01
We examined how personality strengths prospectively predict reactions to negative life events. Participants were 797 community adults from 42 countries. At five points over the course of 1 year, participants completed a series of questionnaires measuring seven personality strengths (hope, grit, meaning in life, curiosity, gratitude, control beliefs, and use of strengths), subjective well-being, and frequency and severity of negative life events. Using hierarchical linear modeling with assessment periods nested within participants, results from lagged analyses found that only hope emerged as a resilience factor. To illustrate the importance of using appropriate lagged analyses in resilience research, we ran nonlagged analyses; these results suggest that all seven personality strengths moderated the effect of negative life events on subjective well-being, with greater strengths associated with healthier outcomes. To provide evidence that personality strengths confer resilience, a prospective examination is needed with the inclusion of events and responses to them. The use of concurrent methodologies and analyses, which is the norm in psychology, often leads to erroneous conclusions. Hope, the ability to generate routes to reach goals and the motivation to use those routes, was shown to be particularly important in promoting resilience. © 2016 Wiley Periodicals, Inc.
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Database on aircraft accidents
International Nuclear Information System (INIS)
Nishio, Masahide; Koriyama, Tamio
2012-09-01
The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to the report, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. This year, the database was revised by adding aircraft accidents in 2010 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2011 database for latest 20 years from 1991 to 2010. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for latest 20 years from 1991 to 2010 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2011 revised database for latest 20 years from 1991 to 2010 shows the followings. The trend of the 2011 database changes little as compared to the last year's one. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. 4 large fixed-wing aircraft accidents, 58 small fixed-wing aircraft accidents, 5 large bladed aircraft accidents and 114 small bladed aircraft accidents occurred. The relevant accidents for evaluating
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Chavez, Carlos; Hammel, Bruce; Hammel, Allan; Moore, John R.
2014-01-01
Unmanned Aircraft Systems (UAS) represent a new capability that will provide a variety of services in the government (public) and commercial (civil) aviation sectors. The growth of this potential industry has not yet been realized due to the lack of a common understanding of what is required to safely operate UAS in the National Airspace System (NAS). To address this deficiency, NASA has established a project called UAS Integration in the NAS (UAS in the NAS), under the Integrated Systems Research Program (ISRP) of the Aeronautics Research Mission Directorate (ARMD). This project provides an opportunity to transition concepts, technology, algorithms, and knowledge to the Federal Aviation Administration (FAA) and other stakeholders to help them define the requirements, regulations, and issues for routine UAS access to the NAS. The safe, routine, and efficient integration of UAS into the NAS requires new radio frequency (RF) spectrum allocations and a new data communications system which is both secure and scalable with increasing UAS traffic without adversely impacting the Air Traffic Control (ATC) communication system. These data communications, referred to as Control and Non-Payload Communications (CNPC), whose purpose is to exchange information between the unmanned aircraft and the ground control station to ensure safe, reliable, and effective unmanned aircraft flight operation. A Communications Subproject within the UAS in the NAS Project has been established to address issues related to CNPC development, certification and fielding. The focus of the Communications Subproject is on validating and allocating new RF spectrum and data link communications to enable civil UAS integration into the NAS. The goal is to validate secure, robust data links within the allocated frequency spectrum for UAS. A vision, architectural concepts, and seed requirements for the future commercial UAS CNPC system have been developed by RTCA Special Committee 203 (SC-203) in the process
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Aircraft Engine Thrust Estimator Design Based on GSA-LSSVM
Sheng, Hanlin; Zhang, Tianhong
2017-08-01
In view of the necessity of highly precise and reliable thrust estimator to achieve direct thrust control of aircraft engine, based on support vector regression (SVR), as well as least square support vector machine (LSSVM) and a new optimization algorithm - gravitational search algorithm (GSA), by performing integrated modelling and parameter optimization, a GSA-LSSVM-based thrust estimator design solution is proposed. The results show that compared to particle swarm optimization (PSO) algorithm, GSA can find unknown optimization parameter better and enables the model developed with better prediction and generalization ability. The model can better predict aircraft engine thrust and thus fulfills the need of direct thrust control of aircraft engine.
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Algebraic and adaptive learning in neural control systems
Ferrari, Silvia
A systematic approach is developed for designing adaptive and reconfigurable nonlinear control systems that are applicable to plants modeled by ordinary differential equations. The nonlinear controller comprising a network of neural networks is taught using a two-phase learning procedure realized through novel techniques for initialization, on-line training, and adaptive critic design. A critical observation is that the gradients of the functions defined by the neural networks must equal corresponding linear gain matrices at chosen operating points. On-line training is based on a dual heuristic adaptive critic architecture that improves control for large, coupled motions by accounting for actual plant dynamics and nonlinear effects. An action network computes the optimal control law; a critic network predicts the derivative of the cost-to-go with respect to the state. Both networks are algebraically initialized based on prior knowledge of satisfactory pointwise linear controllers and continue to adapt on line during full-scale simulations of the plant. On-line training takes place sequentially over discrete periods of time and involves several numerical procedures. A backpropagating algorithm called Resilient Backpropagation is modified and successfully implemented to meet these objectives, without excessive computational expense. This adaptive controller is as conservative as the linear designs and as effective as a global nonlinear controller. The method is successfully implemented for the full-envelope control of a six-degree-of-freedom aircraft simulation. The results show that the on-line adaptation brings about improved performance with respect to the initialization phase during aircraft maneuvers that involve large-angle and coupled dynamics, and parameter variations.
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Phatak, A. V.; Kessler, K. M.
1975-01-01
The selection of the structure of optimal control type models for the human gunner in an anti aircraft artillery system is considered. Several structures within the LQG framework may be formulated. Two basic types are considered: (1) kth derivative controllers; and (2) proportional integral derivative (P-I-D) controllers. It is shown that a suitable criterion for model structure determination can be based on the ensemble statistics of the tracking error. In the case when the ensemble tracking steady state error is zero, it is suggested that a P-I-D controller formulation be used in preference to the kth derivative controller.
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The Resiliency Scale for Young Adults
Prince-Embury, Sandra; Saklofske, Donald H.; Nordstokke, David W.
2017-01-01
The Resiliency Scale for Young Adults (RSYA) is presented as an upward extension of the Resiliency Scales for Children and Adolescents (RSCA). The RSYA is based on the "three-factor model of personal resiliency" including "mastery," "relatedness," and "emotional reactivity." Several stages of scale…
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14 CFR 21.6 - Manufacture of new aircraft, aircraft engines, and propellers.
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Manufacture of new aircraft, aircraft... Manufacture of new aircraft, aircraft engines, and propellers. (a) Except as specified in paragraphs (b) and (c) of this section, no person may manufacture a new aircraft, aircraft engine, or propeller based on...
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International Nuclear Information System (INIS)
Roege, Paul E.; Collier, Zachary A.; Mancillas, James; McDonagh, John A.; Linkov, Igor
2014-01-01
Energy lies at the backbone of any advanced society and constitutes an essential prerequisite for economic growth, social order and national defense. However there is an Achilles heel to today's energy and technology relationship; namely a precarious intimacy between energy and the fiscal, social, and technical systems it supports. Recently, widespread and persistent disruptions in energy systems have highlighted the extent of this dependence and the vulnerability of increasingly optimized systems to changing conditions. Resilience is an emerging concept that offers to reconcile considerations of performance under dynamic environments and across multiple time frames by supplementing traditionally static system performance measures to consider behaviors under changing conditions and complex interactions among physical, information and human domains. This paper identifies metrics useful to implement guidance for energy-related planning, design, investment, and operation. Recommendations are presented using a matrix format to provide a structured and comprehensive framework of metrics relevant to a system's energy resilience. The study synthesizes previously proposed metrics and emergent resilience literature to provide a multi-dimensional model intended for use by leaders and practitioners as they transform our energy posture from one of stasis and reaction to one that is proactive and which fosters sustainable growth. - Highlights: • Resilience is the ability of a system to recover from adversity. • There is a need for methods to quantify and measure system resilience. • We developed a matrix-based approach to generate energy resilience metrics. • These metrics can be used in energy planning, system design, and operations
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Development and experimental characterization of a fuel cell powered aircraft
Energy Technology Data Exchange (ETDEWEB)
Bradley, Thomas H.; Moffitt, Blake A.; Mavris, Dimitri N.; Parekh, David E. [Georgia Institute of Technology, Atlanta, GA 30332-0405 (United States)
2007-09-27
This paper describes the characteristics and performance of a fuel cell powered unmanned aircraft. The aircraft is novel as it is the largest compressed hydrogen fuel cell powered airplane built to date and is currently the only fuel cell aircraft whose design and test results are in the public domain. The aircraft features a 500 W polymer electrolyte membrane fuel cell with full balance of plant and compressed hydrogen storage incorporated into a custom airframe. Details regarding the design requirements, implementation and control of the aircraft are presented for each major aircraft system. The performances of the aircraft and powerplant are analyzed using data from flights and laboratory tests. The efficiency and component power consumption of the fuel cell propulsion system are measured at a variety of flight conditions. The performance of the aircraft powerplant is compared to other 0.5-1 kW-scale fuel cell powerplants in the literature and means of performance improvement for this aircraft are proposed. This work represents one of the first studies of fuel cell powered aircraft to result in a demonstration aircraft. As such, the results of this study are of practical interest to fuel cell powerplant and aircraft designers. (author)
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Integrated Design and Analysis Environment for Safety Critical Human-Automation Systems, Phase II
National Aeronautics and Space Administration — Numerous advances have been made in recent years in the areas of flight deck design, aircraft modeling, resilient control, and vehicle health management. The...
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Database on aircraft accidents
International Nuclear Information System (INIS)
Nishio, Masahide; Koriyama, Tamio
2013-11-01
The Reactor Safety Subcommittee in the Nuclear Safety and Preservation Committee published 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' as the standard method for evaluating probability of aircraft crash into nuclear reactor facilities in July 2002. In response to this issue, Japan Nuclear Energy Safety Organization has been collecting open information on aircraft accidents of commercial airplanes, self-defense force (SDF) airplanes and US force airplanes every year since 2003, sorting out them and developing the database of aircraft accidents for the latest 20 years to evaluate probability of aircraft crash into nuclear reactor facilities. In this report the database was revised by adding aircraft accidents in 2011 to the existing database and deleting aircraft accidents in 1991 from it, resulting in development of the revised 2012 database for the latest 20 years from 1992 to 2011. Furthermore, the flight information on commercial aircrafts was also collected to develop the flight database for the latest 20 years from 1992 to 2011 to evaluate probability of aircraft crash into reactor facilities. The method for developing the database of aircraft accidents to evaluate probability of aircraft crash into reactor facilities is based on the report 'The criteria on assessment of probability of aircraft crash into light water reactor facilities' described above. The 2012 revised database for the latest 20 years from 1992 to 2011 shows the followings. The trend of the 2012 database changes little as compared to the last year's report. (1) The data of commercial aircraft accidents is based on 'Aircraft accident investigation reports of Japan transport safety board' of Ministry of Land, Infrastructure, Transport and Tourism. The number of commercial aircraft accidents is 4 for large fixed-wing aircraft, 58 for small fixed-wing aircraft, 5 for large bladed aircraft and 99 for small bladed aircraft. The relevant accidents
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What do you mean, 'resilient geomorphic systems'?
Thoms, M. C.; Piégay, H.; Parsons, M.
2018-03-01
Resilience thinking has many parallels in the study of geomorphology. Similarities and intersections exist between the scientific discipline of geomorphology and the scientific concept of resilience. Many of the core themes fundamental to geomorphology are closely related to the key themes of resilience. Applications of resilience thinking in the study of natural and human systems have expanded, based on the fundamental premise that ecosystems, economies, and societies must be managed as linked social-ecological systems. Despite geomorphology and resilience sharing core themes, appreciation is limited of the history and development of geomorphology as a field of scientific endeavor by many in the field of resilience, as well as a limited awareness of the foundations of the former in the more recent emergence of resilience. This potentially limits applications of resilience concepts to the study of geomorphology. In this manuscript we provide a collective examination of geomorphology and resilience as a means to conceptually advance both areas of study, as well as to further cement the relevance and importance of not only understanding the complexities of geomorphic systems in an emerging world of interdisciplinary challenges but also the importance of viewing humans as an intrinsic component of geomorphic systems rather than just an external driver. The application of the concepts of hierarchy and scale, fundamental tenets of the study of geomorphic systems, provide a means to overcome contemporary scale-limited approaches within resilience studies. Resilience offers a framework for geomorphology to expand its application into the broader social-ecological domain.
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Probabilistic Modelling of Robustness and Resilience of Power Grid Systems
DEFF Research Database (Denmark)
Qin, Jianjun; Sansavini, Giovanni; Nielsen, Michael Havbro Faber
2017-01-01
The present paper proposes a framework for the modeling and analysis of resilience of networked power grid systems. A probabilistic systems model is proposed based on the JCSS Probabilistic Model Code (JCSS, 2001) and deterministic engineering systems modeling techniques such as the DC flow model...... cascading failure event scenarios (Nan and Sansavini, 2017). The concept of direct and indirect consequences proposed by the Joint Committee on Structural Safety (JCSS, 2008) is utilized to model the associated consequences. To facilitate a holistic modeling of robustness and resilience, and to identify how...... these characteristics may be optimized these characteristics, the power grid system is finally interlinked with its fundamental interdependent systems, i.e. a societal model, a regulatory system and control feedback loops. The proposed framework is exemplified with reference to optimal decision support for resilience...
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Enkephalins: Endogenous Analgesics with an Emerging Role in Stress Resilience
Directory of Open Access Journals (Sweden)
Mathilde S. Henry
2017-01-01
Full Text Available Psychological stress is a state of mental or emotional strain or tension that results from adverse or demanding circumstances. Chronic stress is well known to induce anxiety disorders and major depression; it is also considered a risk factor for Alzheimer’s disease. Stress resilience is a positive outcome that is associated with preserved cognition and healthy aging. Resilience presents psychological and biological characteristics intrinsic to an individual conferring protection against the development of psychopathologies in the face of adversity. How can we promote or improve resilience to chronic stress? Numerous studies have proposed mechanisms that could trigger this desirable process. The roles of enkephalin transmission in the control of pain, physiological functions, like respiration, and affective disorders have been studied for more than 30 years. However, their role in the resilience to chronic stress has received much less attention. This review presents the evidence for an emerging involvement of enkephalin signaling through its two associated opioid receptors, μ opioid peptide receptor and δ opioid peptide receptor, in the natural adaptation to stressful lifestyles.
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Regional employment growth, shocks and regional industrial resilience
DEFF Research Database (Denmark)
Holm, Jacob Rubæk; Østergaard, Christian Richter
2013-01-01
The resilience of regional industries to economic shocks has gained a lot of attention in evolutionary economic geography recently. This paper uses a novel quantitative approach to investigate the regional industrial resilience of the Danish ICT sector to the shock following the burst of the dot......-com bubble. It is shown that regions characterised by small and young ICT service companies were more adaptable and grew more than others, while diversity and urbanisation increased the sensitivity to the business cycle after the shock. Different types of resilient regions are found: adaptively resilient......, rigidly resilient, entrepreneurially resilient and non-resilient regions....
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The resilience of an operating point for a fusion power plant
Energy Technology Data Exchange (ETDEWEB)
Ward, David, E-mail: david.ward@ccfe.ac.uk; Kemp, Richard
2015-10-15
Highlights: • The need to control a power plant changes our view of the optimum design. • The need for control can be reduced by finding resilient design points. • It is important to include resilience and control in selecting design points. • Including these additional constraints reduces flexibility in choice of operating points. - Abstract: The operating point for fusion power plant design concepts is often determined by simultaneously satisfying the requirements of all of the main plant systems and finding an optimum solution, for instance the one with the lowest capital cost or cost of electricity. This static assessment takes no account of the sensitivity of that operating point to variations in key parameters and therefore includes no information about how difficult to adjust and control the chosen operating point may be. Control of the operation point is a large subject with much work still to be done, and is expected to play an increasing role in the future in choosing the optimum design point. Here we present results of two analyses: one relates to the ability to load follow, that is, to vary the power production in the light of varying demands for power from the electricity network; the other investigates in simple terms what choices we can make to improve the resilience of static operating points.
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A Collection of Nonlinear Aircraft Simulations in MATLAB
Garza, Frederico R.; Morelli, Eugene A.
2003-01-01
Nonlinear six degree-of-freedom simulations for a variety of aircraft were created using MATLAB. Data for aircraft geometry, aerodynamic characteristics, mass / inertia properties, and engine characteristics were obtained from open literature publications documenting wind tunnel experiments and flight tests. Each nonlinear simulation was implemented within a common framework in MATLAB, and includes an interface with another commercially-available program to read pilot inputs and produce a three-dimensional (3-D) display of the simulated airplane motion. Aircraft simulations include the General Dynamics F-16 Fighting Falcon, Convair F-106B Delta Dart, Grumman F-14 Tomcat, McDonnell Douglas F-4 Phantom, NASA Langley Free-Flying Aircraft for Sub-scale Experimental Research (FASER), NASA HL-20 Lifting Body, NASA / DARPA X-31 Enhanced Fighter Maneuverability Demonstrator, and the Vought A-7 Corsair II. All nonlinear simulations and 3-D displays run in real time in response to pilot inputs, using contemporary desktop personal computer hardware. The simulations can also be run in batch mode. Each nonlinear simulation includes the full nonlinear dynamics of the bare airframe, with a scaled direct connection from pilot inputs to control surface deflections to provide adequate pilot control. Since all the nonlinear simulations are implemented entirely in MATLAB, user-defined control laws can be added in a straightforward fashion, and the simulations are portable across various computing platforms. Routines for trim, linearization, and numerical integration are included. The general nonlinear simulation framework and the specifics for each particular aircraft are documented.
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Resilience | Science Inventory | US EPA
Resilience is an important framework for understanding and managing complex systems of people and nature that are subject to abrupt and nonlinear change. The idea of ecological resilience was slow to gain acceptance in the scientific community, taking thirty years to become widely accepted (Gunderson 2000, cited under Original Definition). Currently, the concept is commonplace in academics, management, and policy. Although the idea has quantitative roots in the ecological sciences and was proposed as a measurable quality of ecosystems, the broad use of resilience led to an expansion of definitions and applications. Holling’s original definition, presented in 1973 (Holling 1973, cited under Original Definition), was simply the amount of disturbance that a system can withstand before it shifts into an alternative stability domain. Ecological resilience, therefore, emphasizes that the dynamics of complex systems are nonlinear, meaning that these systems can transition, often abruptly, between dynamic states with substantially different structures, functions, and processes. The transition of ecological systems from one state to another frequently has important repercussions for humans. Recent definitions are more normative and qualitative, especially in the social sciences, and a competing definition, that of engineering resilience, is still often used. Resilience is an emergent phenomenon of complex systems, which means it cannot be deduced from the behavior of t
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Measuring county resilience after the 2008 Wenchuan earthquake
Li, X.; Lam, N.; Qiang, Y.; Li, K.; Yin, L.; Liu, S.; Zheng, W.
2015-01-01
The catastrophic earthquake in 2008 has caused serious damage to Wenchuan County and the surrounding area in China. In recent years, great attention has been paid to the resilience of the affected area. This study applied a new framework, the Resilience Inference Measurement (RIM) model, to quantify and validate the community resilience of 105 counties in the affected area. The RIM model uses cluster analysis to classify counties into four resilience levels according to the exposure, damage, and recovery conditions, and then applies discriminant analysis to quantify the influence of socioeconomic characteristics on the county resilience. The analysis results show that counties located right at the epicenter had the lowest resilience, but counties immediately adjacent to the epicenter had the highest resilience capacities. Counties that were farther away from the epicenter returned to normal resiliency. The socioeconomic variables, including sex ratio, per capita GDP, percent of ethnic minority, and medical facilities, were identified as the most influential socio-economic characteristics on resilience. This study provides useful information to improve county resilience to earthquakes and support decision-making for sustainable development.
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Cui, Ke; Han, Ziqiang; Wang, Dongming
2018-02-27
Disaster risk reduction (DRR) activities have given growing attention to building community resilience, but the effects of such efforts on community resilience are still under-investigated, especially in China where the concept of community resilience has only just emerged. Using the Communities Advancing Resilience Toolkit Assessment Survey, data on self-perceived community resilience were collected in 2017 from a post-disaster Chinese rural community in Yingxiu Town, which was the epicenter of the Wenchuan earthquake (Magnitude = 8.0) in the year 2008. Linear regression analyses were conducted to explore the correlations between residents' DRR behaviors and perceived community resilience with the control of their socio-demographic characteristics including age, ethnicity, gender, education, income level, employment status and marital status. Results indicate that residents who volunteered for DRR activities received geological disaster education, participated in evacuation drills, and reported higher income levels had a perception of higher community resilience. Practice research is suggested to help clarify the cause and effect of DRR work on the enhancement of community resilience to disasters in China and abroad. Attention is also called to the development of a Chinese indigenous community resilience concept and assessment instrument.
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Interrogating resilience in health systems development.
van de Pas, Remco; Ashour, Majdi; Kapilashrami, Anuj; Fustukian, Suzanne
2017-11-01
The Fourth Global Symposium on Health Systems Research was themed around 'Resilient and responsive health systems for a changing world.' This commentary is the outcome of a panel discussion at the symposium in which the resilience discourse and its use in health systems development was critically interrogated. The 2014-15 Ebola outbreak in West-Africa added momentum for the wider adoption of resilient health systems as a crucial element to prepare for and effectively respond to crisis. The growing salience of resilience in development and health systems debates can be attributed in part to development actors and philanthropies such as the Rockefeller Foundation. Three concerns regarding the application of resilience to health systems development are discussed: (1) the resilience narrative overrules certain democratic procedures and priority setting in public health agendas by 'claiming' an exceptional policy space; (2) resilience compels accepting and maintaining the status quo and excludes alternative imaginations of just and equitable health systems including the socio-political struggles required to attain those; and (3) an empirical case study from Gaza makes the case that resilience and vulnerability are symbiotic with each other rather than providing a solution for developing a strong health system. In conclusion, if the normative aim of health policies is to build sustainable, universally accessible, health systems then resilience is not the answer. The current threats that health systems face demand us to imagine beyond and explore possibilities for global solidarity and justice in health. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Electronic Warfare: Towed Decoys Could Improve Survivability of Current Navy Aircraft
National Research Council Canada - National Science Library
Aiken, Michael
1997-01-01
Traditionally, DOD'S combat aircraft have used on-board electronic warfare devices called jammers for self-protection against radar-controlled weapons, including missiles and anti-aircraft artillery...
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Vulnerability Analysis of the MAVLink Protocol for Command and Control of Unmanned Aircraft
2013-03-27
Patton, Nikos Karapanos, Lorenz Meier, Peter Schwabe, Andrew Tridgell, Michael Oborne, Dr. Gareth Owen, and Capt Matthew Vincie, all of whom greatly...Frew and T. Brown . Networking Issues For Small Unmanned Aircraft Systems. In Unmanned Aircraft Systems : International Symposium on Unmanned Aerial
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Healthy ageing, resilience and wellbeing.
Cosco, T D; Howse, K; Brayne, C
2017-12-01
The extension of life does not appear to be slowing, representing a great achievement for mankind as well as a challenge for ageing populations. As we move towards an increasingly older population we will need to find novel ways for individuals to make the best of the challenges they face, as the likelihood of encountering some form of adversity increases with age. Resilience theories share a common idea that individuals who manage to navigate adversity and maintain high levels of functioning demonstrate resilience. Traditional models of healthy ageing suggest that having a high level of functioning across a number of domains is a requirement. The addition of adversity to the healthy ageing model via resilience makes this concept much more accessible and more amenable to the ageing population. Through asset-based approaches, such as the invoking of individual, social and environmental resources, it is hoped that greater resilience can be fostered at a population level. Interventions aimed at fostering greater resilience may take many forms; however, there is great potential to increase social and environmental resources through public policy interventions. The wellbeing of the individual must be the focus of these efforts; quality of life is an integral component to the enjoyment of additional years and should not be overlooked. Therefore, it will become increasingly important to use resilience as a public health concept and to intervene through policy to foster greater resilience by increasing resources available to older people. Fostering wellbeing in the face of increasing adversity has significant implications for ageing individuals and society as a whole.
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Crann, Sara E; Barata, Paula C
2016-06-01
While resilience research in the context of intimate partner violence (IPV) is increasing, there remains little known about women's lived experience of resilience. Using a phenomenological approach, this study examined the experience of resilience for adult female survivors of IPV. Sixteen women who were currently experiencing or had previously experienced abuse by an intimate partner participated in semi-structured interviews. Resilience was experienced as multiple cognitive, emotional, and behavioral shifts across three theme areas: toward resistance, in the experience of control, and toward positivity. The results of this study suggest a number of applications for clinical practice and intervention. © The Author(s) 2015.
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Regional Employment Growth, Shocks and Regional Industrial Resilience
DEFF Research Database (Denmark)
Holm, J.R.; Østergaard, Christian Richter
2015-01-01
The resilience of regional industries to economic shocks has gained a lot of attention in evolutionary economic geography recently. This paper uses a novel quantitative approach to investigate the regional industrial resilience of the Danish information and communication technology (ICT) sector...... to the shock following the burst of the dot.com bubble. It is shown that regions characterized by small and young ICT service companies were more adaptable and grew more than others, while diversity and urbanization increased the sensitivity to the business cycle after the shock. Different types of resilient...... regions are found: adaptively resilient, rigidly resilient, entrepreneurially resilient and non-resilient regions....
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Wu, Wei-Wen; Chang, Joanne T; Tsai, Shao-Yu; Liang, Shu-Yuan
Anger is considered a common method used by patients to relieve emotional frustrations. However, this emotional response is not a common research focus for adolescents with cancer. The aim of this study was to determine whether self-concept mediated the relationship between anger and resilience for adolescent patients currently being treated for cancer. A cross-sectional study of 40 adolescents with cancer was conducted. The instruments included the Chinese Beck Self-Concept Inventory, the Chinese Beck Anger Inventory, and the Chinese Resilience Scale. Mediation analysis was also conducted. The results indicate that (1) variations in anger significantly account for 6.86% of observed variations in self-concept, (2) variations in self-concept significantly account for 52.83% of observed variations in resilience, (3) variations in anger significantly account for 10.96% of observed variations in resilience, and (4) when paths in conditions 1 and 2 were controlled, variations in anger through self-concept significantly account for 54.04% of observed variations in resilience, and variations in anger did not significantly account for observed variations in resilience. Gender and age might affect anger control. Despite worse physical functioning and an impacted appearance, participants had normative-to-positive self-concept levels, suggesting that their self-concept might not be affected by cancer. Self-concept might play a mediating role between anger and resilience, thus helping to bridge this knowledge gap. The current gap in knowledge regarding the mediating relationship necessitates the implementation of a large-scale study designed to verify the mediating role of self-concept between anger and resilience.
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Martz, Meghan E; Zucker, Robert A; Schulenberg, John E; Heitzeg, Mary M
2018-04-01
Little is known regarding the combined influence of psychosocial and neural protective mechanisms against substance use. The present study examined the extent to which neuroimaging measures of disinhibition predicted resilience against binge drinking and marijuana use among youth with a family history of substance use disorder (SUD; FH+), accounting for psychosocial measures of behavioral control. Participants were 57 FH+ youth from the Michigan Longitudinal Study categorized into resilient and high-risk groups based on patterns of weekly binge drinking and monthly marijuana use during early adulthood. Psychosocial measures of behavioral control (reactive control and externalizing behavior during early and late adolescence) and neural measures of disinhibition (Go/No-Go task and Monetary Incentive Delay Task (MIDT) measured through functional magnetic resonance imaging (fMRI)) were entered sequentially in hierarchical logistic regression models to predict resilient versus high-risk groups. Greater activation in the right dorsolateral prefrontal cortex (DLPFC) during correctly inhibited trials on the Go/No-Go task was a significant predictor of resilience (OR = 2.46, p accounting for psychosocial measures of behavioral control. Copyright © 2018 Elsevier B.V. All rights reserved.
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Temporal Changes in Community Resilience to Drought Hazard
Mihunov, V.
2017-12-01
The threat of droughts and their associated impacts on the landscape and human communities have long been recognized. While considerable research on the climatological aspect of droughts has been conducted, studies on the resilience of human communities to the effects of drought remain limited. Understanding how different communities respond to and recover from the drought hazard, i.e. their community resilience, should inform the development of better strategies to cope with the hazard. This research assesses community resilience to drought hazard in South-Central U.S. and captures the temporal changes of community resilience in the region facing the climate change. First, the study applies the Resilience Inference Measurement (RIM) framework using the existing drought incidence, crop damage, socio-economic and food-water-energy nexus variables, which allows to assign county-level resilience scores in the study region and derive variables contributing to the resilience. Second, it captures the temporal changes in community resilience by using the model extracted from the RIM study and socio-economic data from several consecutive time periods. The resilience measurement study should help understand the complex process underlying communities' response to the drought impacts. The results identify gaps in resilience planning and help the improvement of the community resilience to the droughts of increasing frequency and intensity.
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A Cybernetic Approach to Assess the Longitudinal Handling Qualities of Aeroelastic Aircraft
Damveld, H.J.
2009-01-01
The future demand for larger and lighter civil transport aircraft leads to more flexible aircraft, which bring their own controlling and handling problems. A review of established handling qualities methods showed that they were either unsuitable for aeroelastic aircraft, or had significant
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Sun, Xiaoyan; Song, Zhenhua; Si, Yawei; Wang, Jin-Hui
2018-06-01
Chronic stress with lack of reward presumably may impair brain reward circuit, leading to major depressive disorder (MDD). Most individuals experiencing chronic stress do not suffer from MDD, i.e., resilience, implying the presence of endogenous anti-depression in the brain. Molecular mechanisms underlying stress-induced depression versus resilience were investigated. Mice were treated by chronic unpredictable mild stress (CUMS) for four weeks. Their mood state was assessed by behavioral tasks, such as sucrose preference, Y-maze and forced swimming testes. To reveal comprehensive molecular profiles of major depression versus resilience, mRNA and microRNA profiles were analyzed by high-throughput sequencing in the ventral tegmental area (VTA) harvested from control, CUMS-susceptible and CUMS-resilience mice. In data analyses of control versus CUMS-susceptible mice as well as control versus CUMS-resilience mice, 1.5 fold ratio in reads per kilo-base per million reads was set as the threshold to judge the involvement of mRNAs and microRNAs in the CUMS, depression or resilience. The downregulation of synaptic vesicle cycle, neurotrophin, GABAergic synapse and morphine addiction as well as the upregulation of transmitter release, calcium signal and cAMP-dependent response element binding are associated to CUMS-susceptibility. The downregulation of tyrosine metabolism and protein process in endoplasmic reticulum as well as the upregulation of amino acid biosynthesis, neuroactive ligand-receptor interaction and dopaminergic synapse are associated to CUMS-resilience. Therefore, the impairment of neurons and GABA/dopaminergic synapses in the VTA is associated with major depression. The upregulation of these entities is associated with resilience. Consistent results obtained from analyzing mRNAs and microRNAs as well as using different approaches strengthen our finding and conclusion. Copyright © 2018. Published by Elsevier Inc.
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Wei, Wei; Taormina, Robert J
2014-12-01
This study refined the concept of resilience and developed four valid and reliable subscales to measure resilience, namely, Determination, Endurance, Adaptability and Recuperability. The study also assessed their hypothesized relationships with six antecedent variables (worry, physiological needs satisfaction, organizational socialization, conscientiousness, future orientation and Chinese values) and with one outcome variable (nurses' career success). The four new 10-item subscale measures of personal resilience were constructed based on their operational definitions and tested for their validity and reliability. All items were included in a questionnaire completed by 244 full-time nurses at two hospitals in China. All four measures demonstrated concurrent validity and had high reliabilities (from 0.74 to 0.78). The hypothesized correlations with the personality and organizational variables were statistically significant and in the predicted directions. Regression analyses confirmed these relationships, which explained 25-32% of the variance for the four resilience facets and 27% of the variance for the nurses' career success. The results provided strong evidence that organizational socialization facilitates resilience, that resilience engenders career success and that identifying the four resilience facets permits a more complete understanding of personal resilience, which could benefit nurses, help nurse administrators with their work and also help in treating patients. © 2014 John Wiley & Sons Ltd.
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Directory of Open Access Journals (Sweden)
Diann S. Eley
2013-11-01
Full Text Available Objective. The health and well being of medical doctors is vital to their longevity and safe practice. The concept of resilience is recognised as a key component of well being and is an important factor in medical training to help doctors learn to cope with challenge, stress, and adversity. This study examined the relationship of resilience to personality traits and resilience in doctors in order to identify the key traits that promote or impair resilience.Methods. A cross sectional cohort of 479 family practitioners in practice across Australia was studied. The Temperament and Character Inventory measured levels of the seven basic dimensions of personality and the Resilience Scale provided an overall measure of resilience. The associations between resilience and personality were examined by Pearson product-moment correlation coefficients, controlling for age and gender (α = 0.05 with an accompanying 95% confidence level and multiple regression analyses.Results. Strong to medium positive correlations were found between Resilience and Self-directedness (r = .614, p < .01, Persistence (r = .498, p < .01, and Cooperativeness (r = .363, p < .01 and negative with Harm Avoidance (r = .−555, p < .01. Individual differences in personality explained 39% of the variance in resilience [F(7, 460 = 38.40, p < .001]. The three traits which contributed significantly to this variance were Self-directedness (β = .33, p < .001, Persistence (β = .22, p < .001 and Harm Avoidance (β = .19, p < .001.Conclusion. Resilience was associated with a personality trait pattern that is mature, responsible, optimistic, persevering, and cooperative. Findings support the inclusion of resilience as a component of optimal functioning and well being in doctors. Strategies for enhancing resilience should consider the key traits that drive or impair it.
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Resilience through adaptation.
Directory of Open Access Journals (Sweden)
Guus A Ten Broeke
Full Text Available Adaptation of agents through learning or evolution is an important component of the resilience of Complex Adaptive Systems (CAS. Without adaptation, the flexibility of such systems to cope with outside pressures would be much lower. To study the capabilities of CAS to adapt, social simulations with agent-based models (ABMs provide a helpful tool. However, the value of ABMs for studying adaptation depends on the availability of methodologies for sensitivity analysis that can quantify resilience and adaptation in ABMs. In this paper we propose a sensitivity analysis methodology that is based on comparing time-dependent probability density functions of output of ABMs with and without agent adaptation. The differences between the probability density functions are quantified by the so-called earth-mover's distance. We use this sensitivity analysis methodology to quantify the probability of occurrence of critical transitions and other long-term effects of agent adaptation. To test the potential of this new approach, it is used to analyse the resilience of an ABM of adaptive agents competing for a common-pool resource. Adaptation is shown to contribute positively to the resilience of this ABM. If adaptation proceeds sufficiently fast, it may delay or avert the collapse of this system.
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Resilience through adaptation.
Ten Broeke, Guus A; van Voorn, George A K; Ligtenberg, Arend; Molenaar, Jaap
2017-01-01
Adaptation of agents through learning or evolution is an important component of the resilience of Complex Adaptive Systems (CAS). Without adaptation, the flexibility of such systems to cope with outside pressures would be much lower. To study the capabilities of CAS to adapt, social simulations with agent-based models (ABMs) provide a helpful tool. However, the value of ABMs for studying adaptation depends on the availability of methodologies for sensitivity analysis that can quantify resilience and adaptation in ABMs. In this paper we propose a sensitivity analysis methodology that is based on comparing time-dependent probability density functions of output of ABMs with and without agent adaptation. The differences between the probability density functions are quantified by the so-called earth-mover's distance. We use this sensitivity analysis methodology to quantify the probability of occurrence of critical transitions and other long-term effects of agent adaptation. To test the potential of this new approach, it is used to analyse the resilience of an ABM of adaptive agents competing for a common-pool resource. Adaptation is shown to contribute positively to the resilience of this ABM. If adaptation proceeds sufficiently fast, it may delay or avert the collapse of this system.
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Sociotechnical Resilience: A Preliminary Concept.
Amir, Sulfikar; Kant, Vivek
2018-01-01
This article presents the concept of sociotechnical resilience by employing an interdisciplinary perspective derived from the fields of science and technology studies, human factors, safety science, organizational studies, and systems engineering. Highlighting the hybrid nature of sociotechnical systems, we identify three main constituents that characterize sociotechnical resilience: informational relations, sociomaterial structures, and anticipatory practices. Further, we frame sociotechnical resilience as undergirded by the notion of transformability with an emphasis on intentional activities, focusing on the ability of sociotechnical systems to shift from one form to another in the aftermath of shock and disturbance. We propose that the triad of relations, structures, and practices are fundamental aspects required to comprehend the resilience of sociotechnical systems during times of crisis. © 2017 Society for Risk Analysis.
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Flight mechanics of a tailless articulated wing aircraft
International Nuclear Information System (INIS)
Paranjape, Aditya A; Chung, Soon-Jo; Selig, Michael S
2011-01-01
This paper investigates the flight mechanics of a micro aerial vehicle without a vertical tail in an effort to reverse-engineer the agility of avian flight. The key to stability and control of such a tailless aircraft lies in the ability to control the incidence angles and dihedral angles of both wings independently. The dihedral angles can be varied symmetrically on both wings to control aircraft speed independently of the angle of attack and flight path angle, while asymmetric dihedral can be used to control yaw in the absence of a vertical stabilizer. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. Numerical continuation and bifurcation analysis are used to compute trim states and assess their stability. This paper lays the foundation for design and stability analysis of a flapping wing aircraft that can switch rapidly from flapping to gliding flight for agile manoeuvring in a constrained environment.
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Flight mechanics of a tailless articulated wing aircraft
Energy Technology Data Exchange (ETDEWEB)
Paranjape, Aditya A; Chung, Soon-Jo; Selig, Michael S, E-mail: sjchung@illinois.edu [Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)
2011-06-15
This paper investigates the flight mechanics of a micro aerial vehicle without a vertical tail in an effort to reverse-engineer the agility of avian flight. The key to stability and control of such a tailless aircraft lies in the ability to control the incidence angles and dihedral angles of both wings independently. The dihedral angles can be varied symmetrically on both wings to control aircraft speed independently of the angle of attack and flight path angle, while asymmetric dihedral can be used to control yaw in the absence of a vertical stabilizer. It is shown that wing dihedral angles alone can effectively regulate sideslip during rapid turns and generate a wide range of equilibrium turn rates while maintaining a constant flight speed and regulating sideslip. Numerical continuation and bifurcation analysis are used to compute trim states and assess their stability. This paper lays the foundation for design and stability analysis of a flapping wing aircraft that can switch rapidly from flapping to gliding flight for agile manoeuvring in a constrained environment.
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Resilience and Coping After Hospital Mergers.
Russo, Cynthia; Calo, Oriana; Harrison, Georgia; Mahoney, Kathleen; Zavotsky, Kathleen Evanovich
The aim of this study was to explore the relationship between resilience and coping in frontline nurses working in a healthcare system that has recently undergone a merger. Hospital mergers are common in the current healthcare environment. Mergers can provide hospital nurses the opportunity to use and develop positive coping strategies to help remain resilient during times of change. An anonymous-survey, quantitative, exploratory, descriptive study design was used. Data were obtained from an electronic survey that was made available to all nurses working in a 3-hospital system located in the northeast. Overall, the results showed that, when nurses reported using positive coping strategies, they report higher levels of resilience. The levels of resilience also varied from campus to campus. The campus that has been through 2 recent mergers reported the highest levels of resilience. This study suggests that, during times of change in the workplace, if nurses are encouraged to use positive coping strategies, they may have higher levels of resilience. This changing environment provides the clinical nurse specialists/clinical nurse educators the opportunity to foster and support frontline nurses in the use of healthy coping strategies and to help improve and maintain a high level of resilience, which is critical in today's healthcare environment.
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DEFF Research Database (Denmark)
Kamyod, Chayapol; Nielsen, Rasmus Hjorth; Prasad, Neeli R.
2012-01-01
) and supporting always on services. Therefore, not only Quality of Service (QoS) but also resilience is required. In this paper, we attempt to evaluate and analyze end-to-end reliability of the IMS system using a model proposed as a combination of Reliability Block Diagram (RBD) and Markov Reward Models (MRMs......Reliability evaluation of systems has been widely researched for improving system resilience especially in designing processes of a complex system. The convergence of different access networks is possible via IP Multimedia Subsystem (IMS) for development toward Next Generation Networks (NGNs......). The resilience of the IMS architecture is studied by applying 1:1 redundancy at different communication scenarios between end users within and across communication domains. The model analysis provides useful reliability characteristics of the system and can be further applied for system design processes....
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Multidimensional approach to complex system resilience analysis
International Nuclear Information System (INIS)
Gama Dessavre, Dante; Ramirez-Marquez, Jose E.; Barker, Kash
2016-01-01
Recent works have attempted to formally define a general metric for quantifying resilience for complex systems as a relationship of performance of the systems against time. The technical content in the proposed work introduces a new model that allows, for the first time, to compare the system resilience among systems (or different modifications to a system), by introducing a new dimension to system resilience models, called stress, to mimic the definition of resilience in material science. The applicability and usefulness of the model is shown with a new heat map visualization proposed in this work, and it is applied to a simulated network resilience case to exemplify its potential benefits. - Highlights: • We analyzed two of the main current metrics of resilience. • We create a new model that relates events with the effects they have. • We develop a novel heat map visualization to compare system resilience. • We showed the model and visualization usefulness in a simulated case.
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Powers, Sheryll Goecke (Compiler)
1995-01-01
Flight research for the F-15 HIDEC (Highly Integrated Digital Electronic Control) program was completed at NASA Dryden Flight Research Center in the fall of 1993. The flight research conducted during the last two years of the HIDEC program included two principal experiments: (1) performance seeking control (PSC), an adaptive, real-time, on-board optimization of engine, inlet, and horizontal tail position on the F-15; and (2) propulsion controlled aircraft (PCA), an augmented flight control system developed for landings as well as up-and-away flight that used only engine thrust (flight controls locked) for flight control. In September 1994, the background details and results of the PSC and PCA experiments were presented in an electronic workshop, accessible through the Dryden World Wide Web (http://www.dfrc.nasa.gov/dryden.html) and as a compact disk.
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Resilience Design Patterns - A Structured Approach to Resilience at Extreme Scale (version 1.0)
Energy Technology Data Exchange (ETDEWEB)
Hukerikar, Saurabh [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Engelmann, Christian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2016-10-01
Reliability is a serious concern for future extreme-scale high-performance computing (HPC) systems. Projections based on the current generation of HPC systems and technology roadmaps suggest that very high fault rates in future systems. The errors resulting from these faults will propagate and generate various kinds of failures, which may result in outcomes ranging from result corruptions to catastrophic application crashes. Practical limits on power consumption in HPC systems will require future systems to embrace innovative architectures, increasing the levels of hardware and software complexities. The resilience challenge for extreme-scale HPC systems requires management of various hardware and software technologies that are capable of handling a broad set of fault models at accelerated fault rates. These techniques must seek to improve resilience at reasonable overheads to power consumption and performance. While the HPC community has developed various solutions, application-level as well as system-based solutions, the solution space of HPC resilience techniques remains fragmented. There are no formal methods and metrics to investigate and evaluate resilience holistically in HPC systems that consider impact scope, handling coverage, and performance & power eciency across the system stack. Additionally, few of the current approaches are portable to newer architectures and software ecosystems, which are expected to be deployed on future systems. In this document, we develop a structured approach to the management of HPC resilience based on the concept of resilience-based design patterns. A design pattern is a general repeatable solution to a commonly occurring problem. We identify the commonly occurring problems and solutions used to deal with faults, errors and failures in HPC systems. The catalog of resilience design patterns provides designers with reusable design elements. We define a design framework that enhances our understanding of the important
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EPA is amending the existing emission standards for oxides of nitrogen (NOx) for new commercial aircraft engines. These standards are equivalent to the NOx emission standards of the United Nations International Civil Aviation Organization (ICAO).
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System Dynamics Modeling for the Resilience in Nuclear Power Plants
Energy Technology Data Exchange (ETDEWEB)
Florah, Kamanj; Kim, Jonghyun [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)
2013-10-15
This paper aims to model and evaluate emergency operation system (EOS) resilience using the System Dynamics. System Dynamics is the study of causal interactions between elements of a complex system. This paper identifies the EOS resilience attributes and their interactions by constructing a causal loop diagram. Then, the interactions are quantified based on literature review and simulated to analyze resilience dynamics. This paper describes the use of system dynamics to improve understanding of the resilience dynamics of complex systems such as emergency operation systems. This paper takes into account two aspects; the strength of resilience attributes interactions and the quantification of dynamic behaviour of resilience over time. This model can be applied to review NPP safety in terms of the resilience level and organization. Simulation results can give managers insights to support their decisions in safety management. A nuclear power plant (NPP) is classified as a safety critical organization whose safety objective is to control hazards that can cause significant harm to the environment, public, or personnel. There has been a significant improvement of safety designs as well as risk analysis tools and methods applied in nuclear power plants over the last decade. Conventional safety analysis methods such as PSA have several limitations they primarily focus on technical dimension, the analysis are linear and sequential, they are dominated by static models, they do not take a systemic view into account, and they focus primarily on why accidents happen and not how success is achieved. Hence new approaches to risk analysis for NPPs are needed to complement the conventional approaches. Resilience is the intrinsic ability of a system to adjust to its functioning prior to, during, or following changes and disturbances, so that it can sustain required operations under both expected and unexpected conditions. An EOS in a NPP refers to a system consisting of personnel
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System Dynamics Modeling for the Resilience in Nuclear Power Plants
International Nuclear Information System (INIS)
Florah, Kamanj; Kim, Jonghyun
2013-01-01
This paper aims to model and evaluate emergency operation system (EOS) resilience using the System Dynamics. System Dynamics is the study of causal interactions between elements of a complex system. This paper identifies the EOS resilience attributes and their interactions by constructing a causal loop diagram. Then, the interactions are quantified based on literature review and simulated to analyze resilience dynamics. This paper describes the use of system dynamics to improve understanding of the resilience dynamics of complex systems such as emergency operation systems. This paper takes into account two aspects; the strength of resilience attributes interactions and the quantification of dynamic behaviour of resilience over time. This model can be applied to review NPP safety in terms of the resilience level and organization. Simulation results can give managers insights to support their decisions in safety management. A nuclear power plant (NPP) is classified as a safety critical organization whose safety objective is to control hazards that can cause significant harm to the environment, public, or personnel. There has been a significant improvement of safety designs as well as risk analysis tools and methods applied in nuclear power plants over the last decade. Conventional safety analysis methods such as PSA have several limitations they primarily focus on technical dimension, the analysis are linear and sequential, they are dominated by static models, they do not take a systemic view into account, and they focus primarily on why accidents happen and not how success is achieved. Hence new approaches to risk analysis for NPPs are needed to complement the conventional approaches. Resilience is the intrinsic ability of a system to adjust to its functioning prior to, during, or following changes and disturbances, so that it can sustain required operations under both expected and unexpected conditions. An EOS in a NPP refers to a system consisting of personnel
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Promoting resilience among nursing students in clinical education.
Thomas, Lisa Jean; Asselin, Marilyn
2018-01-01
Resilience is the ability to overcome adversity and grow stronger from the experience. Increased resilience has been shown to positively impact nurses in practice. With this knowledge, recommendations to incorporate resilience training into nursing education have been made. Research, integrative reviews and a theoretical model of resilience in nursing students are explored in this paper. The authors posit that facilitating resilience is important in the setting of clinical education. Through incorporating resilience training in the clinical setting, educators can better prepare students for challenges in their educational environment and ultimately for nursing practice. Specific strategies for clinical educators to incorporate resilience training are suggested. Strategies are organized into three categories, support, education and reflection. The position of facilitating resilience in clinical education may open a discussion for future educational practices. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Distributed Energy Planning for Climate Resilience
Energy Technology Data Exchange (ETDEWEB)
Stout, Sherry R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hotchkiss, Elizabeth L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Day, Megan H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lee, Nathan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Holm, Alison [National Renewable Energy Laboratory (NREL), Golden, CO (United States)
2018-05-01
At various levels of government across the United States and globally climate resilient solutions are being adopted and implemented. Solutions vary based on predicted hazards, community context, priorities, complexity, and available resources. Lessons are being learned through the implementation process, which can be replicated regardless of level or type of government entity carrying out the resiliency planning. Through a number of analyses and technical support across the world, NREL has learned key lessons related to resilience planning associated with power generation and water distribution. Distributed energy generation is a large factor in building resilience with clean energy technologies and solutions. The technical and policy solutions associated with distributed energy implementation for resilience fall into a few major categories, including spatial diversification, microgrids, water-energy nexus, policy, and redundancy.
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X-36 Tailless Fighter Agility Research Aircraft arrival at Dryden
1996-01-01
The NASA/McDonnell Douglas Corporation (MDC) X-36 Tailless Fighter Agility Research Aircraft in it's hangar at NASA Dryden Flight Research Center, Edwards, California, following its arrival on July 2, 1996. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X-36 prototype weighed approximately 1,250 pounds. It was 19 feet long and three feet high with a wingspan of
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A probabilistic technique for the assessment of complex dynamic system resilience
Balchanos, Michael Gregory
techniques for total system resilience evaluation, based on scenario-based, dynamic system simulations. Physics-based Modeling and Simulation (M&S) is applied for dynamical system behavior analysis, which includes system performance, health monitoring, damage propagation and overall mission capability. For the development of the assessment framework and testing of a resilience assessment technique, a small-scale canonical problem has been formulated, involving a computational model of a degradable and reconfigurable spring-mass-damper SDOF system, in a multiple main and redundant spring configuration. A rule-based feedback controller is responsible for system performance recovery, through the application of different reconfiguration strategies and strategic activation of the necessary main or redundant springs. Uncertainty effects on system operation are introduced through disturbance factors, such as external forces with varying magnitude, input frequency, event duration and occurrence time. Such factors are the basis for scenario formulation, in support of a Monte Carlo simulation analysis. Case studies with varying levels of damping and different reconfiguration strategies, involve the investigation of operational uncertainty effects on system performance, mission capability, and system survivability. These studies furthermore explore uncertainty effects on resilience functions that describe the system's capacities on "restoring" mission capability, on "absorbing" the effects of changing conditions, and on "adapting" to the occurring change. The proposed resilience assessment technique or the Topological Investigation for Resilient and Effective Systems, through Increased Architecture Survivability (TIRESIAS) is then applied and demonstrated for a naval system application, in the form of a reduced scale, reconfigurable cooling network of a naval combatant. Uncertainty effects are modeled through combinations of different number of network fluid leaks. The TIRESIAS
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Autonomous search and surveillance with small fixed wing aircraft
McGee, Timothy Garland
Small unmanned aerial vehicles (UAVs) have the potential to act as low cost tools in a variety of both civilian and military applications including traffic monitoring, border patrol, and search and rescue. While most current operational UAV systems require human operators, advances in autonomy will allow these systems to reach their full potential as sensor platforms. This dissertation specifically focuses on developing advanced control, path planning, search, and image processing techniques that allow small fixed wing aircraft to autonomously collect data. The problems explored were motivated by experience with the development and experimental flight testing of a fleet of small autonomous fixed wing aircraft. These issues, which have not been fully addressed in past work done on ground vehicles or autonomous helicopters, include the influence of wind and turning rate constraints, the non-negligible velocity of ground targets relative to the aircraft velocity, and limitations on sensor size and processing power on small vehicles. Several contributions for the autonomous operation of small fixed wing aircraft are presented. Several sliding surface controllers are designed which extend previous techniques to include variable sliding surface coefficients and the use of spatial vehicle dynamics. These advances eliminate potential singularities in the control laws to follow spatially defined paths and allow smooth transition between controllers. The optimal solution for the problem of path planning through an ordered set of points for an aircraft with a bounded turning rate in the presence of a constant wind is then discussed. Path planning strategies are also explored to guarantee that a searcher will travel within sensing distance of a mobile ground target. This work assumes only a maximum velocity of the target and is designed to succeed for any possible path of the target. Closed-loop approximations of both the path planning and search techniques, using the sliding
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Disease epidemics: Lessons for resilience in an increasingly connected world
Allen, Craig R.; DeWitte, S.N.; Kurth, M.H.; Linkov, I.
2016-01-01
In public health, the term resilience often refers to the personality traits that individuals possess which help them endure and recover from stressors. However, resilience as a system characteristic, especially in regards to complex social-ecological systems, can be informative for public health at scales larger than the individual. Acute shocks to systems occur against a background of existing conditions, which are crucial determinants of the eventual public health outcomes of those shocks, and in the context of complex dependencies among and between ecological and societal elements. Many components of a system's baseline condition are chronic public health concerns themselves and diminish the capacity of the system to perform in the face of acute shocks. The emerging field of resilience management is concerned with holistically assessing and improving a system's ability to prepare for and absorb disruption, and then recover and adapt across physical, information, environmental and social domains. Integrating resilience considerations into current risk- and evidence-based approaches to disease control and prevention1 can move public health efforts toward more proactive and comprehensive solutions for protecting and improving the health of communities. Here, we look to the case of the Black Death as an illustrative case of a dramatic transformation in human history, an acute shock to a system that was underlain by chronic social maladies, to derive lessons about resilience management for public health in contemporary systems.
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Schutte, Paul; Goodrich, Kenneth; Williams, Ralph
2012-01-01
The control automation and interaction paradigm (e.g., manual, autopilot, flight management system) used on virtually all large highly automated aircraft has long been an exemplar of breakdowns in human factors and human-centered design. An alternative paradigm is the Haptic Flight Control System (HFCS) that is part of NASA Langley Research Center s Naturalistic Flight Deck Concept. The HFCS uses only stick and throttle for easily and intuitively controlling the actual flight of the aircraft without losing any of the efficiency and operational benefits of the current paradigm. Initial prototypes of the HFCS are being evaluated and this paper describes one such evaluation. In this evaluation we examined claims regarding improved situation awareness, appropriate workload, graceful degradation, and improved pilot acceptance. Twenty-four instrument-rated pilots were instructed to plan and fly four different flights in a fictitious airspace using a moderate fidelity desktop simulation. Three different flight control paradigms were tested: Manual control, Full Automation control, and a simplified version of the HFCS. Dependent variables included both subjective (questionnaire) and objective (SAGAT) measures of situation awareness, workload (NASA-TLX), secondary task performance, time to recognize automation failures, and pilot preference (questionnaire). The results showed a statistically significant advantage for the HFCS in a number of measures. Results that were not statistically significant still favored the HFCS. The results suggest that the HFCS does offer an attractive and viable alternative to the tactical components of today s FMS/autopilot control system. The paper describes further studies that are planned to continue to evaluate the HFCS.
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Kornhaber, Rachel; Mclean, Loyola; Betihavas, Vasiliki; Cleary, Michelle
2018-01-01
To synthesize the qualitative research evidence that explored how survivors of adult spinal cord injury experience and make sense of resilience. Spinal cord injury is often a sudden and unexpected life-changing event requiring complex and long-term rehabilitation. The development of resilience is essential in determining how spinal cord injury survivors negotiate this injury and rehabilitation. A qualitative systematic review and thematic synthesis of the research evidence. CINAHL, PubMed, Embase, Scopus and PsycINFO were searched, no restriction dates were used. Methodological quality was assessed using the Critical Appraisal Skills Programme checklist. Thematic synthesis focused on how survivors of adult spinal cord injury experience and make sense of resilience. Six qualitative research articles reported the experiences of 84 spinal cord injury survivors. Themes identified were: uncertainty and regaining independence; prior experiences of resilience; adopting resilient thinking; and strengthening resilience through supports. Recovery and rehabilitation following spinal cord survivors is influenced by the individual's capacity for resilience. Resilience may be influenced by previous life experiences and enhanced by supportive nursing staff encouraging self-efficacy. Survivors identified the need for active involvement in decision-making about their care to enable a sense of regaining control of their lives. This has the potential to have a significant impact on their self-efficacy and in turn health outcomes. © 2017 John Wiley & Sons Ltd.
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Bromley, Elizabeth; Eisenman, David P; Magana, Aizita; Williams, Malcolm; Kim, Biblia; McCreary, Michael; Chandra, Anita; Wells, Kenneth B
2017-10-21
Community resilience is a key concept in the National Health Security Strategy that emphasizes development of multi-sector partnerships and equity through community engagement. Here, we describe the advancement of CR principles through community participatory methods in the Los Angeles County Community Disaster Resilience (LACCDR) initiative. LACCDR, an initiative led by the Los Angeles County Department of Public Health with academic partners, randomized 16 community coalitions to implement either an Enhanced Standard Preparedness or Community Resilience approach over 24 months. Facilitated by a public health nurse or community educator, coalitions comprised government agencies, community-focused organizations and community members. We used thematic analysis of data from focus groups ( n = 5) and interviews ( n = 6 coalition members; n = 16 facilitators) to compare coalitions' strategies for operationalizing community resilience levers of change (engagement, partnership, self-sufficiency, education). We find that strategies that included bidirectional learning helped coalitions understand and adopt resilience principles. Strategies that operationalized community resilience levers in mutually reinforcing ways (e.g., disseminating information while strengthening partnerships) also secured commitment to resilience principles. We review additional challenges and successes in achieving cross-sector collaboration and engaging at-risk groups in the resilience versus preparedness coalitions. The LACCDR example can inform strategies for uptake and implementation of community resilience and uptake of the resilience concept and methods.
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Directory of Open Access Journals (Sweden)
Elizabeth Bromley
2017-10-01
Full Text Available Community resilience is a key concept in the National Health Security Strategy that emphasizes development of multi-sector partnerships and equity through community engagement. Here, we describe the advancement of CR principles through community participatory methods in the Los Angeles County Community Disaster Resilience (LACCDR initiative. LACCDR, an initiative led by the Los Angeles County Department of Public Health with academic partners, randomized 16 community coalitions to implement either an Enhanced Standard Preparedness or Community Resilience approach over 24 months. Facilitated by a public health nurse or community educator, coalitions comprised government agencies, community-focused organizations and community members. We used thematic analysis of data from focus groups (n = 5 and interviews (n = 6 coalition members; n = 16 facilitators to compare coalitions’ strategies for operationalizing community resilience levers of change (engagement, partnership, self-sufficiency, education. We find that strategies that included bidirectional learning helped coalitions understand and adopt resilience principles. Strategies that operationalized community resilience levers in mutually reinforcing ways (e.g., disseminating information while strengthening partnerships also secured commitment to resilience principles. We review additional challenges and successes in achieving cross-sector collaboration and engaging at-risk groups in the resilience versus preparedness coalitions. The LACCDR example can inform strategies for uptake and implementation of community resilience and uptake of the resilience concept and methods.
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Relationship Between Resilience and Quality of Life in Diabetics
International Nuclear Information System (INIS)
Nawaz, A.; Malik, J. A.; Batool, A.
2014-01-01
Objective: To determine the relationship between resilience and quality of life of diabetes patients controlling the effect of personal level (i.e., gender, age, and income) and disease-specific (i.e., duration of disease, and current glucose level) demographics. Study Design: Analytical study. Place and Duration of Study: Outpatient Departments of various hospitals in Islamabad and Rawalpindi, from October to November 2012. Methodology: Patients diagnosed with diabetes taking treatment in an outdoor patients facility were included. Patients with a major diabetes complications causing or coexistent with a physical disability, medical condition or psychiatric comorbidity were excluded. Informed consent was taken from patients before administration of questionnaires. The patients were asked to respond to a demographic sheet, State-Trait resilience inventory, and WHO-Quality of Life BREF. Statistical testing was conducting using bivariate correlation, Mann-Whitney U-test, and multiple linear regression analysis for moderation testing. Results: There were 242 patients including (n=108, 44% females; and n=134, 56% males) aged 17 - 85 years with mean of 44.56 +- 16.56 years. Trait resilience predicted all aspects of quality of life of diabetic patients (b range = 0.30 to 0.42, p < .01) and explained 17% variance in physical functioning, 29% in psychological functioning, 17% in environmental functioning, 30% in social dimension, and 29% in overall quality of life. Duration of diabetes moderated effect of state resilience on all aspects of quality of life (b interaction range = 0.20 to 0.26, p < .05) and explained an additional 4% variance in physical functioning, 5% in psychological functioning, 3% in environmental functioning, 5% in social dimension, and 4% in overall quality of life of diabetics. Conclusion: Trait resilience has unconditional positive effect on all aspect of quality of life. Long standing diabetics may benefit from intervention addressing state
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The Resilience-Enabling Value of African Folktales: The Read-Me-To-Resilience Intervention
Theron, Linda; Cockcroft, Kate; Wood, Lesley
2017-01-01
Resilience, or the process of adjusting well to adversity, draws on personal and social ecological resources (i.e., caregiving and community supports). Previous research--conducted mostly in the Global North--has shown that bibliotherapy offers a way to support children in identifying and utilizing resilience-enabling resources. In so doing,…
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Economic resilience lessons from the ShakeOut earthquake scenario
Wein, A.; Rose, A.
2011-01-01
Following a damaging earthquake, “business interruption” (BI)—reduced production of goods and services—begins and continues long after the ground shaking stops. Economic resilience reduces BI losses by making the best use of the resources available at a given point in time (static resilience) or by speeding recovery through repair and reconstruction (dynamic resilience), in contrast to mitigation that prevents damage in the first place. Economic resilience is an important concept to incorporate into economic loss modeling and in recovery and contingency planning. Economic resilience framework includes the applicability of resilience strategies to production inputs and output, demand- and supply-side effects, inherent and adaptive abilities, and levels of the economy. We use our resilience framework to organize and share strategies that enhance economic resilience, identify overlooked resilience strategies, and present evidence and structure of resilience strategies for economic loss modelers. Numerous resilience strategies are compiled from stakeholder discussions about the ShakeOut Scenario (Jones et. al. 2008). Modeled results of ShakeOut BI sector losses reveal variable effectiveness of resilience strategies for lengthy disruptions caused by fire-damaged buildings and water service outages. Resilience is a complement to mitigation and may, in fact, have cost and all-hazards advantages.
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Resilience of primary healthcare professionals: a systematic review.
Robertson, Helen D; Elliott, Alison M; Burton, Christopher; Iversen, Lisa; Murchie, Peter; Porteous, Terry; Matheson, Catriona
2016-06-01
Modern demands and challenges among healthcare professionals can be particularly stressful and resilience is increasingly necessary to maintain an effective, adaptable, and sustainable workforce. However, definitions of, and associations with, resilience have not been examined within the primary care context. To examine definitions and measures of resilience, identify characteristics and components, and synthesise current evidence about resilience in primary healthcare professionals. A systematic review was undertaken to identify studies relating to the primary care setting. Ovid(®), Embase(®), CINAHL, PsycINFO, and Scopus databases were searched in December 2014. Text selections and data extraction were conducted by paired reviewers working independently. Data were extracted on health professional resilience definitions and associated factors. Thirteen studies met the inclusion criteria: eight were quantitative, four qualitative, and one was an intervention study. Resilience, although multifaceted, was commonly defined as involving positive adaptation to adversity. Interactions were identified between personal growth and accomplishment in resilient physicians. Resilience, high persistence, high self-directedness, and low avoidance of challenges were strongly correlated; resilience had significant associations with traits supporting high function levels associated with demanding health professional roles. Current resilience measures do not allow for these different aspects in the primary care context. Health professional resilience is multifaceted, combining discrete personal traits alongside personal, social, and workplace features. A measure for health professional resilience should be developed and validated that may be used in future quantitative research to measure the effect of an intervention to promote it. © British Journal of General Practice 2016.
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Resilience concepts in psychiatry demonstrated with bipolar disorder.
Angeler, David G; Allen, Craig R; Persson, Maj-Liz
2018-02-09
The term resilience describes stress-response patterns of subjects across scientific disciplines. In ecology, advances have been made to clearly distinguish resilience definitions based on underlying mechanistic assumptions. Engineering resilience (rebound) is used for describing the ability of subjects to recover from adverse conditions (disturbances), and is the rate of recovery. In contrast, the ecological resilience definition considers a systemic change: when complex systems (including humans) respond to disturbances by reorganizing into a new regime (stable state) where structural and functional aspects have fundamentally changed relative to the prior regime. In this context, resilience is an emergent property of complex systems. We argue that both resilience definitions and uses are appropriate in psychology and psychiatry, but although the differences are subtle, the implications and uses are profoundly different. We borrow from the field of ecology to discuss resilience concepts in the mental health sciences. In psychology and psychiatry, the prevailing view of resilience is adaptation to, coping with, and recovery (engineering resilience) from adverse social and environmental conditions. Ecological resilience may be useful for describing vulnerability, onset, and the irreversibility patterns of mental disorders. We discuss this in the context of bipolar disorder. Rebound, adaptation, and coping are processes that are subsumed within the broader systemic organization of humans, from which ecological resilience emanates. Discerning resilience concepts in psychology and psychiatry has potential for a mechanistically appropriate contextualization of mental disorders at large. This might contribute to a refinement of theory and contextualize clinical practice within the broader systemic functioning of mental illnesses.
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Clinical correlates of resilience factors in geriatric depression.
Laird, Kelsey T; Lavretsky, Helen; Paholpak, Pattharee; Vlasova, Roza M; Roman, Michael; St Cyr, Natalie; Siddarth, Prabha
2018-01-16
Traditional perspectives conceptualize resilience as a trait and depression as resulting from resilience deficiency. However, research indicates that resilience varies substantially even among adults who are clinically depressed, as well as across the lifespan of an individual. Few studies have investigated resilience in depression, and even fewer have examined resilience in depressed older adults. Three hundred thirty-seven adults ≥60 years with major depressive disorder completed the Connor-Davidson Resilience Scale (CD-RISC) and measures of mental health, quality of life (QOL), and medical comorbidity. Exploratory factor analysis was used to explore the factor structure of the CD-RISC. Correlations and general linear models were used to examine associations between resilience and other variables. The rotated component matrix indicated a four-factor model. Sorting of items by highest factor loading revealed constructs associated with (1) grit, (2) active coping self-efficacy, (3) accommodative coping self-efficacy, and (4) spirituality. Resilience was significantly correlated with increased age, lower cognitive functioning, greater cerebrovascular risk, and greater medical comorbidity. Resilience was negatively associated with mental health symptoms (depression, apathy, and anxiety) and positively associated with QOL. The final optimal model identified less depression, less apathy, greater medical comorbidity, higher QOL, and minority (non-White) race as factors that significantly explained variability in resilience. Resilience was significantly associated with a range of mental health constructs in a sample of older adults with depression. Future clinical trials and dismantling studies may help determine whether interventions targeting grit, active coping, accommodative coping, and spirituality can increase resilience and help prevent and treat depression in older adults.
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Resilience of primary healthcare professionals: a systematic review
Robertson, Helen D; Elliott, Alison M; Burton, Christopher; Iversen, Lisa; Murchie, Peter; Porteous, Terry; Matheson, Catriona
2016-01-01
Background Modern demands and challenges among healthcare professionals can be particularly stressful and resilience is increasingly necessary to maintain an effective, adaptable, and sustainable workforce. However, definitions of, and associations with, resilience have not been examined within the primary care context. Aim To examine definitions and measures of resilience, identify characteristics and components, and synthesise current evidence about resilience in primary healthcare professionals. Design and setting A systematic review was undertaken to identify studies relating to the primary care setting. Method Ovid®, Embase®, CINAHL, PsycINFO, and Scopus databases were searched in December 2014. Text selections and data extraction were conducted by paired reviewers working independently. Data were extracted on health professional resilience definitions and associated factors. Results Thirteen studies met the inclusion criteria: eight were quantitative, four qualitative, and one was an intervention study. Resilience, although multifaceted, was commonly defined as involving positive adaptation to adversity. Interactions were identified between personal growth and accomplishment in resilient physicians. Resilience, high persistence, high self-directedness, and low avoidance of challenges were strongly correlated; resilience had significant associations with traits supporting high function levels associated with demanding health professional roles. Current resilience measures do not allow for these different aspects in the primary care context. Conclusion Health professional resilience is multifaceted, combining discrete personal traits alongside personal, social, and workplace features. A measure for health professional resilience should be developed and validated that may be used in future quantitative research to measure the effect of an intervention to promote it. PMID:27162208
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Flight Dynamics Simulation Modeling and Control of a Large Flexible Tiltrotor Aircraft
2014-09-01
analyses as it retains a momentum theory type rotor system. Later, CAMRAD, a comprehensive aeromechanics and dynamics model capa- ble of multi-rotor and...isotropic, linearly elastic material. 8. All blades are identical. 9. Euler- Bernoulli beam theory is used, implying plane cross sections remain plane and...aircraft could be improved to achieve a higher fidelity structural response. Currently, flexible wings are modeled as Bernoulli beams. Actual aircraft
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Design Of Vertical Take-Off And Landing VTOL Aircraft System
Directory of Open Access Journals (Sweden)
Win Ko Ko Oo
2017-04-01
Full Text Available Vertical Take Off and Landing Vehicles VTOL are the ones which can take off and land from the same place without need of long runway. This paper presents the design and implementation of tricopter mode and aircraft mode for VTOL aircraft system. Firstly the aircraft design is considered for VTOL mode. And then the mathematical model of the VTOL aircraft is applied to test stability. In this research the KK 2.1 flight controller is used for VTOL mode and aircraft mode. The first part is to develop the VTOL mode and the next part is the transition of VTOL mode to aircraft mode. This paper gives brief idea about numerous types of VTOLs and their advantages over traditional aircraftsand insight to various types of tricopter and evaluates their configurations.
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Resilience engineering and the built environment
DEFF Research Database (Denmark)
Hollnagel, Erik
2014-01-01
important to understand the range of conditions about why and how the system functions in the desired' mode as well as unwanted' modes. Resilience is the capacity to sustain operations under both expected and unexpected conditions. The unexpected conditions are not only threats but also opportunities.......The possible relations between resilience engineering and built environments are explored. Resilience engineering has been concerned with the safe and efficient functioning of large and small industrial systems. These may be described as built systems or artefacts. The resilience engineering...... approach argues that if the performance of systems is to be resilient, then they must be able to respond, monitor, learn and anticipate. The last ability in particular means that they must be able to consider themselves vis-a-vis their environment, i.e. be sentient and reflective systems. In practice...
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Aurora Flight Sciences' Perseus B Remotely Piloted Aircraft in Flight
1998-01-01
A long, slender wing and a pusher propeller at the rear characterize the Perseus B remotely piloted research aircraft, seen here during a test flight in June 1998. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST
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Alzheimer's aggression: influences on caregiver coping and resilience.
Wilks, Scott E; Little, Kristina G; Gough, Heather R; Spurlock, Wanda J
2011-04-01
This study assessed impact of Alzheimer's patients' aggressive behavior (AD aggression) on caregiver coping strategies (task-, emotion-, and avoidance-focused) and caregiver resilience, and examined whether coping strategy moderated the AD aggression-caregiver resilience relationship. Informal caregivers across Louisiana (N = 419) completed surveys with measures of demographics, AD aggression, caregiver coping strategies, and caregiver resilience. Task-focused coping positively related to resilience. Aggression negatively predicted caregiver resilience. Emotion- and avoidance-focused coping strategies separately interacted with aggression and increased its negative relationship to caregiver resilience. Task-focused coping showed no moderation. Implications for social work professionals are discussed.
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Directory of Open Access Journals (Sweden)
Namrata Bhatia
2015-08-01
Full Text Available We examined the associations of mothers’ perception of neighborhood quality and maternal resilience with risk of preterm birth and whether maternal resilience moderated the effect of neighborhood quality perception. We analyzed data from 10,758 women with singleton births who participated in 2010–2012 Los Angeles Mommy and Baby surveys. Multilevel logistic regression models assessed the effects of mothers’ perception of neighborhood quality and maternal resilience on preterm birth (yes/no, controlling for potential confounders and economic hardship index, a city-level measure of neighborhood quality. Interaction terms were assessed for moderation. Mothers’ perception of neighborhood quality and maternal resilience were each uniquely associated with preterm birth, independent of potential confounders (p-values < 0.05. The risk of preterm birth among mothers who perceived their neighborhood as of poor quality was about 30% greater compared to mothers who perceived their neighborhood as of good quality; the risk was 12% greater among mothers with low resilience compared to those with high resilience. Effects of neighborhood quality were not modified by maternal resilience. The findings suggest that mothers’ perception of neighborhood quality and resilience are associated with the risk of preterm birth. Further research should explore whether initiatives aimed at improving neighborhood quality and women’s self-esteem may improve birth outcomes.
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The Resilience Assessment Framework: a common indicator for land management?
Cowie, Annette; Metternicht, Graciela; O'Connell, Deborah
2015-04-01
applicable to all agro-ecosystems, and that involvement of stakeholders is critical to discerning the critical variables to be assessed, the proposed framework uses an iterative participatory approach to characterise the system, considering also interactions across and within scales; identify the controlling variables, and assess proximity to thresholds, and adaptive capacity. The framework consists of four elements: Element A: System description; Element B Assessing the system; Element C Adaptive governance and management; Element D Participatory process. Element D is intended as a cross-cutting element, applying across Elements A to C, although Elements A and B can be applied as a desktop activity in a preliminary assessment. The results of the assessment are synthesised in "Resilience action indicators", that summarise the state of the system with respect to the need to adapt or transform. The presentation will summarise the framework and the responses of expert reviewers who identified strengths of the approach, and challenges for implementation, particularly at program and national scales. The presentation will emphasise the conceptual basis for the approach, and the role of scientists in testing, refining and operationalizing the approach.
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Building Resilience through Humor.
Berg, Debra Vande; Van Brockern, Steve
1995-01-01
Research on resilience suggests that a sense of humor helps to stress-proof children in conflict. Reports on a workshop for educators and youth workers convened to explore ways humor is being used to foster positive development and resilience with troubled youth. Describes applications of humor front-line professionals report as useful in their…
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Childhood personality as a harbinger of competence and resilience in adulthood.
Shiner, Rebecca L; Masten, Ann S
2012-05-01
This study examined the significance of childhood Big Five personality traits for competence and resilience in early adulthood. Resilience was defined in terms of adaptive success in age-salient developmental tasks despite significant adversity throughout childhood/adolescence. The Project Competence Longitudinal Study tracked 205 young people from childhood (around age 10) to emerging adulthood (EA, age 20) and young adulthood (YA, age 30; 90% retention). Multimethod composites were created for personality traits, adversity exposure, and adult outcomes of academic achievement, work, rule-abiding conduct, friendship, and romantic relationships. Regressions showed significant main effects of childhood personality predicting adult outcomes, controlling for adversity, with few interaction effects. In person-focused analyses, the resilient group in EA and YA (high competence, high adversity) showed higher childhood conscientiousness, agreeableness, and openness and lower neuroticism than the maladaptive group (low competence, high adversity). The competent (high competence, low adversity) and resilient groups showed similar childhood traits. Turnaround cases, who changed from the maladaptive group in EA to the resilient group in YA, exhibited higher childhood conscientiousness than persistently maladaptive peers. Findings suggest that children on pathways to success in adulthood, whether facing low or high adversity, have capacities for emotion regulation, empathy and connection, dedication to schoolwork, and mastery and exploration.
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A resilience markers framework for small teams
Energy Technology Data Exchange (ETDEWEB)
Furniss, Dominic, E-mail: d.furniss@ucl.ac.u [UCL Interaction Centre, University College London, Gower Street, London WC1E 6BT (United Kingdom); Back, Jonathan; Blandford, Ann [UCL Interaction Centre, University College London, Gower Street, London WC1E 6BT (United Kingdom); Hildebrandt, Michael; Broberg, Helena [OECD Halden Reactor Project, PO Box 173, 1751 Halden (Norway)
2011-01-15
Processes that enable an effective response to unexpected events and vulnerabilities that lie outside the scope of formal procedures can be described as being resilient. There are many such descriptions of resilience within and across different domains. Comparison and generalisation is difficult because resilience is not a component of a system and should be understood as an emergent property. Here we provide a framework for reasoning about resilience that requires representation of the level of analysis (from the individual to operational), a traceable link from abstract theory to specific observations, resilience mechanisms, and contextual factors. This moves forward an agenda to systematically observe concrete manifestations of resilience within and across domains. We illustrate the application of the framework by considering a case study of the performance of nuclear power plant (NPP) operators in an experimental scenario. This paper focuses on the small team level of analysis. The framework presented here provides the basis for developing concrete measures for improving the resilience of organisations through training, system design, and organisational learning.
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A resilience markers framework for small teams
International Nuclear Information System (INIS)
Furniss, Dominic; Back, Jonathan; Blandford, Ann; Hildebrandt, Michael; Broberg, Helena
2011-01-01
Processes that enable an effective response to unexpected events and vulnerabilities that lie outside the scope of formal procedures can be described as being resilient. There are many such descriptions of resilience within and across different domains. Comparison and generalisation is difficult because resilience is not a component of a system and should be understood as an emergent property. Here we provide a framework for reasoning about resilience that requires representation of the level of analysis (from the individual to operational), a traceable link from abstract theory to specific observations, resilience mechanisms, and contextual factors. This moves forward an agenda to systematically observe concrete manifestations of resilience within and across domains. We illustrate the application of the framework by considering a case study of the performance of nuclear power plant (NPP) operators in an experimental scenario. This paper focuses on the small team level of analysis. The framework presented here provides the basis for developing concrete measures for improving the resilience of organisations through training, system design, and organisational learning.
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Torre, Gerardo De La; Yucelen, Tansel
2018-03-01
Control algorithms of networked multiagent systems are generally computed distributively without having a centralised entity monitoring the activity of agents; and therefore, unforeseen adverse conditions such as uncertainties or attacks to the communication network and/or failure of agent-wise components can easily result in system instability and prohibit the accomplishment of system-level objectives. In this paper, we study resilient coordination of networked multiagent systems in the presence of misbehaving agents, i.e. agents that are subject to exogenous disturbances that represent a class of adverse conditions. In particular, a distributed adaptive control architecture is presented for directed and time-varying graph topologies to retrieve a desired networked multiagent system behaviour. Apart from the existing relevant literature that make specific assumptions on the graph topology and/or the fraction of misbehaving agents, we show that the considered class of adverse conditions can be mitigated by the proposed adaptive control approach that utilises a local state emulator - even if all agents are misbehaving. Illustrative numerical examples are provided to demonstrate the theoretical findings.
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Systems Measures of Water Distribution System Resilience
Energy Technology Data Exchange (ETDEWEB)
Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murray, Regan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-01-01
Resilience is a concept that is being used increasingly to refer to the capacity of infrastructure systems to be prepared for and able to respond effectively and rapidly to hazardous events. In Section 2 of this report, drinking water hazards, resilience literature, and available resilience tools are presented. Broader definitions, attributes and methods for measuring resilience are presented in Section 3. In Section 4, quantitative systems performance measures for water distribution systems are presented. Finally, in Section 5, the performance measures and their relevance to measuring the resilience of water systems to hazards is discussed along with needed improvements to water distribution system modeling tools.
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Resilience in a reborn nation: Validation of the Lithuanian Resilience Scale for Adults (RSA).
Hilbig, Jan; Viliūnienė, Rima; Friborg, Oddgeir; Pakalniškienė, Vilmantė; Danilevičiūtė, Vita
2015-07-01
Resilience, as an ability to withstand or rebound from crisis or adversity, is becoming an increasingly significant concept in health promotion and well-being. Individuals exhibiting resilience use skills or resources flexibly to solve situational demands. The Resilience Scale for Adults (RSA) may be used to assess protective resources, and the aim of the present study was to validate the Lithuanian translation. The translated RSA was administered to a clinical (n=125) and a non clinical sample (n=499) to examine the discriminant validity of the RSA items with a confirmatory factor analysis, the internal consistency as well as construct validity by correlating it with the Quick Psycho-Affective Symptoms Scan (QPASS). The internal consistency, the test-retest stability and the factor structure were replicated as adequate, thus indicating good psychometric properties and support of discriminant validity. Females reported more resilience resources for the domains of social competence, family cohesion and social resources compared to men. The RSA subscales correlated negatively with the QPASS scores, and patients reported significantly less resilience resources than non-patients, thus indicating construct validity. Valid psychometric tools for research purposes and routine every-day use are urgently needed in Lithuania, a young nation still under numerous challenges due to social, economic and political transitions. The RSA represents a reliable and valid tool for assessing protective factors. Assessing resilience factors may extend the understanding of factors relevant for mental health problems as well as treatment prognosis beyond the capabilities of mere symptom oriented approaches. Copyright © 2015 Elsevier Inc. All rights reserved.
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Sempier, T.
2017-12-01
Communicating risk due to flooding, sea level rise, storm surge, and other natural hazards is a complex task when attempting to build resilience in coastal communities. There are a number of challenges related to preparing for, responding to, and recovering from coastal storms. Successful resilience planning must include a wide range of sectors including, but not limited to local government, business, non-profit, religious, academia, and healthcare. Years of experience working with communities in the Gulf of Mexico has helped create a process that is both inclusive and effective at bringing the right people to the table and gaining momentum towards resilience efforts. The Coastal Community Resilience Index (CRI), a self-assessment for community leaders, has been implemented in 54 Gulf communities with funding that provides small grant awards to help communities take action to address gaps and vulnerabilities identified in the assessment process. To maintain momentum with resilience actions, the Gulf Climate and Resilience Community of Practice (CoP) encourages local municipality participants to share lessons learned and best practices from their implementation projects in an annual symposium. Recently, both graduate and undergraduate students have been exposed to the CRI and CoP as avenues to work through solutions to complex problems at the local level. In addition, a new generation of high school students has been introduced to the CRI. Their engagement in the process is building a more informed citizenry that will take on the leadership and decision-making roles in the future. Investing in multiple age groups and sectors through the CRI and CoP is building capacity for whole community resilience in the Gulf of Mexico. This presentation will focus on methods that have been successful in the Gulf of Mexico for creating effective change in local municipalities towards resilience actions. Discussion will include decision support tools for engaging local
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A quantitative framework for assessing ecological resilience
Quantitative approaches to measure and assess resilience are needed to bridge gaps between science, policy, and management. In this paper, we suggest a quantitative framework for assessing ecological resilience. Ecological resilience as an emergent ecosystem phenomenon can be de...
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Resilient Renewable Energy Microgrids
Energy Technology Data Exchange (ETDEWEB)
Anderson, Katherine H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DiOrio, Nicholas A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Butt, Robert S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cutler, Dylan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Richards, Allison [Unaffiliated
2017-11-14
This presentation for the Cable-Tec Expo 2017 offers information about how renewable microgrids can be used to increase resiliency. It includes information about why renewable energy battery diesel hybrids microgrids should be considered for backup power, how to estimate economic savings of microgrids, quantifying the resiliency gain of microgrids, and where renewable microgrids will be successful.
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The Resilient Family Firm: Stakeholder Outcomes and Institutional Effects
van Essen, M.|info:eu-repo/dai/nl/357514491; Strike, Vanessa M.; Carney, M.; Sapp, S.
Manuscript Type Empirical Research Question/Issue Our study seeks to explain the relationship between publicly listed family-controlled firms (FCFs) and investor and employee outcomes before and during the global financial crisis. Theoretically, we develop hypotheses suggesting that FCF resilience
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Crider, Dennis; Foster, John V.
2012-01-01
In-flight loss of control remains the leading contributor to aviation accident fatalities, with stall upsets being the leading causal factor. The February 12, 2009. Colgan Air, Inc., Continental Express flight 3407 accident outside Buffalo, New York, brought this issue to the forefront of public consciousness and resulted in recommendations from the National Transportation Safety Board to conduct training that incorporates stalls that are fully developed and develop simulator standards to support such training. In 2010, Congress responded to this accident with Public Law 11-216 (Section 208), which mandates full stall training for Part 121 flight operations. Efforts are currently in progress to develop recommendations on implementation of stall training for airline pilots. The International Committee on Aviation Training in Extended Envelopes (ICATEE) is currently defining simulator fidelity standards that will be necessary for effective stall training. These recommendations will apply to all civil transport aircraft including straight-wing turboprop aircraft. Government-funded research over the previous decade provides a strong foundation for stall/post-stall simulation for swept-wing, conventional tail jets to respond to this mandate, but turboprops present additional and unique modeling challenges. First among these challenges is the effect of power, which can provide enhanced flow attachment behind the propellers. Furthermore, turboprops tend to operate for longer periods in an environment more susceptible to ice. As a result, there have been a significant number of turboprop accidents as a result of the early (lower angle of attack) stalls in icing. The vulnerability of turboprop configurations to icing has led to studies on ice accumulation and the resulting effects on flight behavior. Piloted simulations of these effects have highlighted the important training needs for recognition and mitigation of icing effects, including the reduction of stall margins
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Hopkin, Paul
There have been many high-profile incidents in recent times that have affected both individual organisations and large parts of society. In response to these disasters and their consequences, there has been increasing focus on the concept of 'resilience'. Airmic worked with Cranfield School of Management to investigate the features of resilient organisations and whether common characteristics could be identified. The research summarised in this paper discovered five principles that increase an organisation's level of resilence. The paper also reports on the actions taken by organisations to embed these resilience principles into four main business enablers. These business enablers in combination represent the business model of the organisation. The overall conclusion of the research was that, in order to achieve a state of enhanced resilience, organisations need to be aware of risks and threats they face and then combine the actions required to be 'risk compliant' with the ability to be 'risk responsive'.
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Social ecology of resilience and Sumud of Palestinians.
Marie, Mohammad; Hannigan, Ben; Jones, Aled
2018-01-01
The aim of this article is to provide an overview of theoretical perspectives and practical research knowledge in relation to 'resilience', the resilience of Palestinians in particular and the related concept of 'Sumud'. 'Sumud' is a Palestinian idea that is interwoven with ideas of personal and collective resilience and steadfastness. It is also a socio-political concept and refers to ways of surviving in the context of occupation, chronic adversity, lack of resources and limited infrastructure. The concept of 'resilience' has deep roots, going back at least to the 10th century when Arabic scholars suggested strategies to cope with life adversity. In Europe, research into resilience extends back to the 1800s. The understanding of resilience has developed over four overlapping waves. These focus on individual traits, protective factors, ecological assets and (in the current wave) social ecological factors. The current wave of resilience research focuses on the contribution of cultural contextualisation and is an approach that is discussed in this article, which draws on Arabic and English language literature located through a search of multiple databases (CINAHL, British Nursing Index, ASSIA, MEDLINE, PsycINFO and EMBASE). Findings suggest that 'Sumud' is linked to the surrounding cultural context and can be thought of as an innovative, social ecological, approach to promoting resilience. We show that resilience is a prerequisite to 'Sumud', meaning that the individual has to be resilient in order to stay and not to leave their place, position or community. We close by pressing the case for studies which investigate resilience especially in underdeveloped countries such as Palestine (occupied Palestinian territories), and which reveal how resilience is embedded in pre-existing cultural contexts.
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A Versatile Simulation Environment of FTC Architectures for Large Transport Aircraft
Ossmann, Daniel; Varga, Andreas; Simon, Hecker
2010-01-01
We present a simulation environment with 3-D stereo visualization facilities destined for an easy setup and versatile assessment of fault detection and diagnosis based fault tolerant control systems. This environment has been primarily developed as a technology demonstrator of advanced reconfigurable flight control systems and is based on a realistic six degree of freedom flexible aircraft model. The aircraft control system architecture includes a flexible fault detection and diagnosis syste...
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Taylor, S. M.; Worman, S. L.; Bennett, R.; Bassow, A.
2017-12-01
The Department of the Interior (DOI) partnered with the National Fish and Wildlife Foundation (NFWF) to administer an external funding competition to support coastal resilience projects in the region affected by Hurricane Sandy. The projects complement the DOI Bureau-led projects, but are led by state and local governments, universities, non-profits, community groups, tribes, and other non-Federal entities. In total, the Hurricane Sandy Resilience Program invested over $750 million in approximately 180 projects to repair damage and improve the resilience of habitats, communities and infrastructure to future storms and sea level rise. Project activities include waterway connection and opening, living shoreline, marsh restoration, community resilience planning, data/mapping/modeling, and beach and dune restoration. DOI and NFWF initiated a resilience assessment in 2015 to evaluate the impact of this investment. The assessment began by clarifying the program's resilience goals and the development of ecological and socio-economic metrics across the project activities. Using these metrics, the evaluation is assessing the ecological and community outcomes, cost effectiveness of activities, improved scientific understanding, and temporal and spatial scaling of benefits across resilience activities. Recognizing the unique opportunity afforded by the scale and distribution of projects, NFWF and DOI have invested in monitoring through 2024 to better understand how these projects perform over time. This presentation will describe the evaluation questions, approach, long-term monitoring, online metrics portal, and findings to date.
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Developing a community-based flood resilience measurement standard
Keating, Adriana; Szoenyi, Michael; Chaplowe, Scott; McQuistan, Colin; Campbell, Karen
2015-04-01
Given the increased attention to resilience-strengthening in international humanitarian and development work, there has been concurrent interest in its measurement and the overall accountability of "resilience strengthening" initiatives. The literature is reaching beyond the polemic of defining resilience to its measurement. Similarly, donors are increasingly expecting organizations to go beyond claiming resilience programing to measuring and showing it. However, key questions must be asked, in particular "Resilience of whom and to what?". There is no one-size-fits-all solution. The approach to measuring resilience is dependent on the audience and the purpose of the measurement exercise. Deriving a resilience measurement system needs to be based on the question it seeks to answer and needs to be specific. This session highlights key lessons from the Zurich Flood Resilience Alliance approach to develop a flood resilience measurement standard to measure and assess the impact of community based flood resilience interventions, and to inform decision-making to enhance the effectiveness of these interventions. We draw on experience in methodology development to-date, together with lessons from application in two case study sites in Latin America. Attention will be given to the use of a consistent measurement methodology for community resilience to floods over time and place; challenges to measuring a complex and dynamic phenomenon such as community resilience; methodological implications of measuring community resilience versus impact on and contribution to this goal; and using measurement and tools such as cost-benefit analysis to prioritize and inform strategic decision making for resilience interventions. The measurement tool follows the five categories of the Sustainable Livelihoods Framework and the 4Rs of complex adaptive systems - robustness, rapidity, redundancy and resourcefulness -5C-4R. A recent white paper by the Zurich Flood Resilience Alliance traces the
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Aircraft Test & Evaluation Facility (Hush House)
Federal Laboratory Consortium — The Aircraft Test and Evaluation Facility (ATEF), or Hush House, is a noise-abated ground test sub-facility. The facility's controlled environment provides 24-hour...
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Assessment instruments of urban resilience
Directory of Open Access Journals (Sweden)
Giovanna Saporiti
2012-07-01
Full Text Available The objective of this work is to highlight the aspects related to the resilient capacity of a neoecosistema. Clarifying what does it means to speak about a resilient neoecosistema and which are the specific characters that make him capable of change and adaptation when facing an environmental, social or economic threat, it will be possible to understand the efficacy related to the model of urban development. From the individuation of perturbing factors of this capacity, it will be possible to generate a panel of the resilient capacity linked to three different ambits that represent the three characteristic elements of natural ecosystems: its physic structure, the persons and the interaction processes between them so we would be able to make explicit the specific characters of resilience distinguished from those of sustainability and urban quality.
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Priority Queues Resilient to Memory Faults
DEFF Research Database (Denmark)
Jørgensen, Allan Grønlund; Moruz, Gabriel; Mølhave, Thomas
2007-01-01
In the faulty-memory RAM model, the content of memory cells can get corrupted at any time during the execution of an algorithm, and a constant number of uncorruptible registers are available. A resilient data structure in this model works correctly on the set of uncorrupted values. In this paper we...... introduce a resilient priority queue. The deletemin operation of a resilient priority queue returns either the minimum uncorrupted element or some corrupted element. Our resilient priority queue uses $O(n)$ space to store $n$ elements. Both insert and deletemin operations are performed in $O(\\log n......+\\delta)$ time amortized, where $\\delta$ is the maximum amount of corruptions tolerated. Our priority queue matches the performance of classical optimal priority queues in the RAM model when the number of corruptions tolerated is $O(\\log n)$. We prove matching worst case lower bounds for resilient priority...