Closed-Loop Optimal Control Implementations for Space Applications

DTIC Science & Technology

2016-12-01

analyses of a series of optimal control problems, several real- time optimal control algorithms are developed that continuously adapt to feedback on the...through the analyses of a series of optimal control problems, several real- time optimal control algorithms are developed that continuously adapt to...information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering

NASTRAN thermal analyzer: Theory and application including a guide to modeling engineering problems, volume 2. [sample problem library guide

NASA Technical Reports Server (NTRS)

Jackson, C. E., Jr.

1977-01-01

A sample problem library containing 20 problems covering most facets of Nastran Thermal Analyzer modeling is presented. Areas discussed include radiative interchange, arbitrary nonlinear loads, transient temperature and steady-state structural plots, temperature-dependent conductivities, simulated multi-layer insulation, and constraint techniques. The use of the major control options and important DMAP alters is demonstrated.

Self-tuning regulators for multicyclic control of helicopter vibration

NASA Technical Reports Server (NTRS)

Johnson, W.

1982-01-01

A class of algorithms for the multicyclic control of helicopter vibration and loads is derived and discussed. This class is characterized by a linear, quasi-static, frequency-domain model of the helicopter response to control; identification of the helicopter model by least-squared-error or Kalman filter methods; and a minimum variance or quadratic performance function controller. Previous research on such controllers is reviewed. The derivations and discussions cover the helicopter model; the identification problem, including both off-line and on-line (recursive) algorithms; the control problem, including both open-loop and closed-loop feedback; and the various regulator configurations possible within this class. Conclusions from analysis and numerical simulations of the regulators provide guidance in the design and selection of algorithms for further development, including wind tunnel and flight tests.

Problem-Solving Skills Appraisal Mediates Hardiness and Suicidal Ideation among Malaysian Undergraduate Students

PubMed Central

Abdollahi, Abbas; Talib, Mansor Abu; Yaacob, Siti Nor; Ismail, Zanariah

2015-01-01

Objectives Recent evidence suggests that suicidal ideation is increased among university students, it is essential to increase our knowledge concerning the etiology of suicidal ideation among university students. This study was conducted to examine the relationships between problem-solving skills appraisal, hardiness, and suicidal ideation among university students. In addition, this study was conducted to examine problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) as a potential mediator between hardiness and suicidal ideation. Methods The participants consisted of 500 undergraduate students from Malaysian public universities. Results Structural Equation Modelling (SEM) estimated that undergraduate students with lower hardiness, poor problem-solving confidence, external personal control of emotion, and avoiding style was associated with higher suicidal ideation. Problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) partially mediated the relationship between hardiness and suicidal ideation. Conclusion These findings underline the importance of studying mediating processes that explain how hardiness affects suicidal ideation. PMID:25830229

Test-specific control conditions for functional analyses.

PubMed

Fahmie, Tara A; Iwata, Brian A; Querim, Angie C; Harper, Jill M

2013-01-01

Most functional analyses of problem behavior include a common condition (play or noncontingent reinforcement) as a control for both positive and negative reinforcement. However, test-specific conditions that control for each potential source of reinforcement may be beneficial occasionally. We compared responding during alone, ignore, play, and differential reinforcement of other behavior (DRO) control conditions for individuals whose problem behavior was maintained by positive or negative reinforcement. Results showed that all of the conditions were effective controls for problem behavior maintained by positive reinforcement; however, the DRO condition was consistently ineffective as a control for problem behavior maintained by negative reinforcement. Implications for the design of functional analyses and future research are discussed. © Society for the Experimental Analysis of Behavior.

Sleep problems and suicide attempts among adolescents: a case-control study.

PubMed

Koyawala, Neel; Stevens, Jack; McBee-Strayer, Sandra M; Cannon, Elizabeth A; Bridge, Jeffrey A

2015-01-01

This study used a case-control design to compare sleep disturbances in 40 adolescents who attempted suicide with 40 never-suicidal adolescents. Using hierarchical logistic regression analyses, we found that self-reported nighttime awakenings were significantly associated with attempted suicide, after controlling for antidepressant use, antipsychotic use, affective problems, and being bullied. In a separate regression analysis, the parent-reported total sleep problems score also predicted suicide attempt status, controlling for key covariates. No associations were found between suicide attempts and other distinct sleep problems, including falling asleep at bedtime, sleeping a lot during the day, trouble waking up in the morning, sleep duration, and parent-reported nightmares. Clinicians should be aware of sleep problems as potential risk factors for suicide attempts for adolescents.

Seminar on Understanding Digital Control and Analysis in Vibration Test Systems, part 2

NASA Technical Reports Server (NTRS)

1975-01-01

A number of techniques for dealing with important technical aspects of the random vibration control problem are described. These include the generation of pseudo-random and true random noise, the control spectrum estimation problem, the accuracy/speed tradeoff, and control correction strategies. System hardware, the operator-system interface, safety features, and operational capabilities of sophisticated digital random vibration control systems are also discussed.

A variable-gain output feedback control design methodology

NASA Technical Reports Server (NTRS)

Halyo, Nesim; Moerder, Daniel D.; Broussard, John R.; Taylor, Deborah B.

1989-01-01

A digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach provides a control theory framework within which the operating range of a control law can be significantly extended. Furthermore, the approach avoids the major shortcomings of the conventional gain-scheduling techniques. The optimal variable gain output feedback control problem is solved by embedding the Multi-Configuration Control (MCC) problem, previously solved at ICS. An algorithm to compute the optimal variable gain output feedback control gain matrices is developed. The algorithm is a modified version of the MCC algorithm improved so as to handle the large dimensionality which arises particularly in variable-gain control problems. The design methodology developed is applied to a reconfigurable aircraft control problem. A variable-gain output feedback control problem was formulated to design a flight control law for an AFTI F-16 aircraft which can automatically reconfigure its control strategy to accommodate failures in the horizontal tail control surface. Simulations of the closed-loop reconfigurable system show that the approach produces a control design which can accommodate such failures with relative ease. The technique can be applied to many other problems including sensor failure accommodation, mode switching control laws and super agility.

Do job demands and job control affect problem-solving?

PubMed

Bergman, Peter N; Ahlberg, Gunnel; Johansson, Gun; Stoetzer, Ulrich; Aborg, Carl; Hallsten, Lennart; Lundberg, Ingvar

2012-01-01

The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.

A modified approach to controller partitioning

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Veillette, Robert J.

1993-01-01

The idea of computing a decentralized control law for the integrated flight/propulsion control of an aircraft by partitioning a given centralized controller is investigated. An existing controller partitioning methodology is described, and a modified approach is proposed with the objective of simplifying the associated controller approximation problem. Under the existing approach, the decentralized control structure is a variable in the partitioning process; by contrast, the modified approach assumes that the structure is fixed a priori. Hence, the centralized controller design may take the decentralized control structure into account. Specifically, the centralized controller may be designed to include all the same inputs and outputs as the decentralized controller; then, the two controllers may be compared directly, simplifying the partitioning process considerably. Following the modified approach, a centralized controller is designed for an example aircraft mode. The design includes all the inputs and outputs to be used in a specified decentralized control structure. However, it is shown that the resulting centralized controller is not well suited for approximation by a decentralized controller of the given structure. The results indicate that it is not practical in general to cast the controller partitioning problem as a direct controller approximation problem.

Scenario-based, closed-loop model predictive control with application to emergency vehicle scheduling

NASA Astrophysics Data System (ADS)

Goodwin, Graham. C.; Medioli, Adrian. M.

2013-08-01

Model predictive control has been a major success story in process control. More recently, the methodology has been used in other contexts, including automotive engine control, power electronics and telecommunications. Most applications focus on set-point tracking and use single-sequence optimisation. Here we consider an alternative class of problems motivated by the scheduling of emergency vehicles. Here disturbances are the dominant feature. We develop a novel closed-loop model predictive control strategy aimed at this class of problems. We motivate, and illustrate, the ideas via the problem of fluid deployment of ambulance resources.

Solving ill-posed control problems by stabilized finite element methods: an alternative to Tikhonov regularization

NASA Astrophysics Data System (ADS)

Burman, Erik; Hansbo, Peter; Larson, Mats G.

2018-03-01

Tikhonov regularization is one of the most commonly used methods for the regularization of ill-posed problems. In the setting of finite element solutions of elliptic partial differential control problems, Tikhonov regularization amounts to adding suitably weighted least squares terms of the control variable, or derivatives thereof, to the Lagrangian determining the optimality system. In this note we show that the stabilization methods for discretely ill-posed problems developed in the setting of convection-dominated convection-diffusion problems, can be highly suitable for stabilizing optimal control problems, and that Tikhonov regularization will lead to less accurate discrete solutions. We consider some inverse problems for Poisson’s equation as an illustration and derive new error estimates both for the reconstruction of the solution from the measured data and reconstruction of the source term from the measured data. These estimates include both the effect of the discretization error and error in the measurements.

Time-domain finite elements in optimal control with application to launch-vehicle guidance. PhD. Thesis

NASA Technical Reports Server (NTRS)

Bless, Robert R.

1991-01-01

A time-domain finite element method is developed for optimal control problems. The theory derived is general enough to handle a large class of problems including optimal control problems that are continuous in the states and controls, problems with discontinuities in the states and/or system equations, problems with control inequality constraints, problems with state inequality constraints, or problems involving any combination of the above. The theory is developed in such a way that no numerical quadrature is necessary regardless of the degree of nonlinearity in the equations. Also, the same shape functions may be employed for every problem because all strong boundary conditions are transformed into natural or weak boundary conditions. In addition, the resulting nonlinear algebraic equations are very sparse. Use of sparse matrix solvers allows for the rapid and accurate solution of very difficult optimization problems. The formulation is applied to launch-vehicle trajectory optimization problems, and results show that real-time optimal guidance is realizable with this method. Finally, a general problem solving environment is created for solving a large class of optimal control problems. The algorithm uses both FORTRAN and a symbolic computation program to solve problems with a minimum of user interaction. The use of symbolic computation eliminates the need for user-written subroutines which greatly reduces the setup time for solving problems.

Human factors aspects of air traffic control

NASA Technical Reports Server (NTRS)

Older, H. J.; Cameron, B. J.

1972-01-01

An overview of human factors problems associated with the operation of present and future air traffic control systems is presented. A description is included of those activities and tasks performed by air traffic controllers at each operational position within the present system. Judgemental data obtained from controllers concerning psychological dimensions related to these tasks and activities are also presented. The analysis includes consideration of psychophysiological dimensions of human performance. The role of the human controller in present air traffic control systems and his predicted role in future systems is described, particularly as that role changes as the result of the system's evolution towards a more automated configuration. Special attention is directed towards problems of staffing, training, and system operation. A series of ten specific research and development projects are recommended and suggested work plans for their implementation are included.

Adaptive boundary concentration control using Zakai equation

NASA Astrophysics Data System (ADS)

Tenno, R.; Mendelson, A.

2010-06-01

A mean-variance control problem is formulated with respect to a partially observed nonlinear system that includes unknown constant parameters. A physical prototype of the system is the cathode surface reaction in an electrolysis cell, where the controller aim is to keep the boundary concentration of species in the near vicinity of the cathode surface low but not zero. The boundary concentration is a diffusion-controlled process observed through the measured current density and, in practice, controlled through the applied voltage. The former incomplete data control problem is converted to complete data-to the so-called separated control problem whose solution is given by the infinite-dimensional Zakai equation. In this article, the separated control problem is solved numerically using pathwise integration of the Zakai equation. This article demonstrates precise tracking of the target trajectory with a rapid convergence of estimates to unknown parameters, which take place simultaneously with control.

Analysis of routine communication in the air traffic control system

NASA Technical Reports Server (NTRS)

Clark, Herbert H.; Morrow, Daniel; Rodvoid, Michelle

1990-01-01

The present project has three related goals. The first is to describe the organization of routine controller-pilot communication. This includes identifying the basic units of communication and how they are organized into discourse, how controllers and pilots use language to achieve their goals, and what topics they discuss. The second goal is to identify the type and frequency of problems that interrupt routine information transfer and prompt pilots and controllers to focus on the communication itself. The authors analyze the costs of these problems in terms of communication efficiency, and the techniques used to resolve these problems. Third, the authors hope to identify factors associated with communication problems, such as deviations from conventional air traffic control procedures.

Simulation Exercises for an Undergraduate Digital Process Control Course.

ERIC Educational Resources Information Center

Reeves, Deborah E.; Schork, F. Joseph

1988-01-01

Presents six problems from an alternative approach to homework traditionally given to follow-up lectures. Stresses the advantage of longer term exercises which allow for creativity and independence on the part of the student. Problems include: "System Model,""Open-Loop Simulation,""PID Control,""Dahlin…

33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

Code of Federal Regulations, 2012 CFR

2012-07-01

... identification by common and scientific name of the plant or plants concerned, origin of infestation and likely... control operations or engineering works, including control methods, materials, equipment and procedures... operation control, the report should include a brief statement of the special problems in control methods...

33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

Code of Federal Regulations, 2013 CFR

2013-07-01

... identification by common and scientific name of the plant or plants concerned, origin of infestation and likely... control operations or engineering works, including control methods, materials, equipment and procedures... operation control, the report should include a brief statement of the special problems in control methods...

Parental adjustment, parenting attitudes and emotional and behavioral problems in children with selective mutism.

PubMed

Alyanak, Behiye; Kılınçaslan, Ayşe; Harmancı, Halime Sözen; Demirkaya, Sevcan Karakoç; Yurtbay, Tülin; Vehid, Hayriye Ertem

2013-01-01

The present study investigated emotional and behavioral problems in children with selective mutism (SM) along with the psychological adjustment and parenting attitudes of their mothers and fathers. Participants included 26 children with SM (mean age = 8.11 ± 2.11 years), 32 healthy controls (mean age = 8.18 ± 2.55 years) and the parents of all children. Children with SM displayed higher problem scores than controls in a variety of emotional and behavioral parameters. They predominantly displayed internalizing problems, whereas aggressive and delinquent behavior was described among a subsample of the children. Significant differences existed between the SM and control groups only in paternal psychopathology, which included anxiety and depression. They did not differ with respect to maternal psychological distress or mother or father reported parental attitudes. Another important result of the present study was that the severity of emotional and behavioral problems of children with SM was correlated with maternal psychopathology but not paternal psychopathology. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effortful Control, Explicit Processing, and the Regulation of Human Evolved Predispositions

ERIC Educational Resources Information Center

MacDonald, Kevin B.

2008-01-01

This article analyzes the effortful control of automatic processing related to social and emotional behavior, including control over evolved modules designed to solve problems of survival and reproduction that were recurrent over evolutionary time. The inputs to effortful control mechanisms include a wide range of nonrecurrent…

Analysis and control of hourglass instabilities in underintegrated linear and nonlinear elasticity

NASA Technical Reports Server (NTRS)

Jacquotte, Olivier P.; Oden, J. Tinsley

1994-01-01

Methods are described to identify and correct a bad finite element approximation of the governing operator obtained when under-integration is used in numerical code for several model problems: the Poisson problem, the linear elasticity problem, and for problems in the nonlinear theory of elasticity. For each of these problems, the reason for the occurrence of instabilities is given, a way to control or eliminate them is presented, and theorems of existence, uniqueness, and convergence for the given methods are established. Finally, numerical results are included which illustrate the theory.

Some challenges in designing a lunar, Martian, or microgravity CELSS.

PubMed

Salisbury, F B

1992-01-01

The design of a bioregenerative life-support system (a Controlled Ecological Life-Support System or CELSS) for long-duration stays on the moon, Mars, or in a space craft poses formidable problems in engineering and in theory. Technological (hardware) problems include: (1) Creation and control of gas composition and pressure, temperature, light, humidity, and air circulation, especially in microgravity to 1/3 xg and in the vacuum of space. Light (energy demanding), CO2 levels, and the rooting media are special problems for plants. (2) Developing specialized equipment for food preparation. (3) Equipment development for waste recycling. (4) Development of computer systems for environmental monitoring and control as well as several other functions. Problems of theory (software) include: (1) Determining crop species and cultivars (some bred especially for CELSS). (2) Optimum environments and growing and harvesting techniques for each crop. (3) Best and most efficient food-preparation techniques and required equipment. (4) Best and most efficient waste-recycling techniques and equipment. This topic includes questions about the extent of closure, resupply, and waste storage. (5) How to achieve long-term stability. (6) How to avoid catastrophic failures--and how to recover from near-catastrophic failures (for example, plant diseases). Many problems must be solved.

Some challenges in designing a lunar, Martian, or microgravity CELSS

NASA Astrophysics Data System (ADS)

Salisbury, Frank B.

The design of a bioregenerative life-support system (a Controlled Ecological Life-Support System or CELSS) for long-duration stays on the moon, Mars, or in a space craft poses formidable problems in engineering and in theory. Technological (hardware) problems include: (1) Creation and control of gas composition and pressure, temperature, light, humidity, and air circulation, especially in microgravity to 1/3xg and in the vacuum of space. Light (energy demanding), CO 2 levels, and the rooting media are special problems for plants. (2) Developing specialized equipment for food preparation. (3) Equipment development for waste recycling. (4) Development of computer systems for environmental monitoring and control as well as several other functions. Problems of theory (software) include: (1) Determining crop species and cultivars (some bred especially for CELSS). (2) Optimum environments and growing and harvesting techniques for each crop. (3) Best and most efficient food-preparation techniques and required equipment. (4) Best and most efficient waste-recycling techniques and equipment. This topic includes questions about the extent of closure, resupply, and waste storage. (5) How to achieve long-term stability. (6) How to avoid catastrophic failures-and how to recover from near-catastrophic failures (for example, plant diseases). Many problems must be solved.

Comparative study of flare control laws. [optimal control of b-737 aircraft approach and landing

NASA Technical Reports Server (NTRS)

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.

7 CFR 205.206 - Crop pest, weed, and disease management practice standard.

Code of Federal Regulations, 2010 CFR

2010-01-01

... problems may be controlled through mechanical or physical methods including but not limited to: (1... problems may be controlled through: (1) Mulching with fully biodegradable materials; (2) Mowing; (3...) Plastic or other synthetic mulches: Provided, That, they are removed from the field at the end of the...

7 CFR 205.206 - Crop pest, weed, and disease management practice standard.

Code of Federal Regulations, 2011 CFR

2011-01-01

... problems may be controlled through mechanical or physical methods including but not limited to: (1... problems may be controlled through: (1) Mulching with fully biodegradable materials; (2) Mowing; (3...) Plastic or other synthetic mulches: Provided, That, they are removed from the field at the end of the...

Arithmetic Word-Problem-Solving in Huntington's Disease

ERIC Educational Resources Information Center

Allain, P.; Verny, C.; Aubin, G.; Pinon, K.; Bonneau, D.; Dubas, F.; Gall, D.L.

2005-01-01

The purpose of this study was to examine executive functioning in patients with Huntington's disease using an arithmetic word-problem-solving task including eight solvable problems of increasing complexity and four aberrant problems. Ten patients with Huntington's disease and 12 normal control subjects matched by age and education were tested.…

Control optimization, stabilization and computer algorithms for aircraft applications

NASA Technical Reports Server (NTRS)

1975-01-01

Research related to reliable aircraft design is summarized. Topics discussed include systems reliability optimization, failure detection algorithms, analysis of nonlinear filters, design of compensators incorporating time delays, digital compensator design, estimation for systems with echoes, low-order compensator design, descent-phase controller for 4-D navigation, infinite dimensional mathematical programming problems and optimal control problems with constraints, robust compensator design, numerical methods for the Lyapunov equations, and perturbation methods in linear filtering and control.

Finite dimensional approximation of a class of constrained nonlinear optimal control problems

NASA Technical Reports Server (NTRS)

Gunzburger, Max D.; Hou, L. S.

1994-01-01

An abstract framework for the analysis and approximation of a class of nonlinear optimal control and optimization problems is constructed. Nonlinearities occur in both the objective functional and in the constraints. The framework includes an abstract nonlinear optimization problem posed on infinite dimensional spaces, and approximate problem posed on finite dimensional spaces, together with a number of hypotheses concerning the two problems. The framework is used to show that optimal solutions exist, to show that Lagrange multipliers may be used to enforce the constraints, to derive an optimality system from which optimal states and controls may be deduced, and to derive existence results and error estimates for solutions of the approximate problem. The abstract framework and the results derived from that framework are then applied to three concrete control or optimization problems and their approximation by finite element methods. The first involves the von Karman plate equations of nonlinear elasticity, the second, the Ginzburg-Landau equations of superconductivity, and the third, the Navier-Stokes equations for incompressible, viscous flows.

Social Information Processing of Positive and Negative Hypothetical Events in Children with ADHD and Conduct Problems and Controls

ERIC Educational Resources Information Center

Andrade, Brendan F.; Waschbusch, Daniel A.; Doucet, Amelie; King, Sara; MacKinnon, Maura; McGrath, Patrick J.; Stewart, Sherry H.; Corkum, Penny

2012-01-01

Objective: This study examined social information processing (SIP) of events with varied outcomes in children with ADHD and conduct problems (CPs; defined as oppositional defiant disorder [ODD] or conduct disorder [CD]) and controls. Method: Participants were 64 children (46 boys, 18 girls) aged 6 to 12, including 39 with ADHD and 25 controls.…

Some aspects of control of a large-scale dynamic system

NASA Technical Reports Server (NTRS)

Aoki, M.

1975-01-01

Techniques of predicting and/or controlling the dynamic behavior of large scale systems are discussed in terms of decentralized decision making. Topics discussed include: (1) control of large scale systems by dynamic team with delayed information sharing; (2) dynamic resource allocation problems by a team (hierarchical structure with a coordinator); and (3) some problems related to the construction of a model of reduced dimension.

Present and Future Problems of Airplane Propulsion

NASA Technical Reports Server (NTRS)

Ackeret, J

1941-01-01

Some of the problems considered in this report include: thermodynamics of surface friction, application of thick wing sections, special applications of controllable propellers, and gas turbines for aircraft.

NASA aviation safety reporting system

NASA Technical Reports Server (NTRS)

1981-01-01

Aviation safety reports that relate to loss of control in flight, problems that occur as a result of similar sounding alphanumerics, and pilot incapacitation are presented. Problems related to the go around maneuver in air carrier operations, and bulletins (and FAA responses to them) that pertain to air traffic control systems and procedures are included.

Optimal control problems with mixed control-phase variable equality and inequality constraints

NASA Technical Reports Server (NTRS)

Makowski, K.; Neustad, L. W.

1974-01-01

In this paper, necessary conditions are obtained for optimal control problems containing equality constraints defined in terms of functions of the control and phase variables. The control system is assumed to be characterized by an ordinary differential equation, and more conventional constraints, including phase inequality constraints, are also assumed to be present. Because the first-mentioned equality constraint must be satisfied for all t (the independent variable of the differential equation) belonging to an arbitrary (prescribed) measurable set, this problem gives rise to infinite-dimensional equality constraints. To obtain the necessary conditions, which are in the form of a maximum principle, an implicit-function-type theorem in Banach spaces is derived.

Finite horizon optimum control with and without a scrap value

NASA Astrophysics Data System (ADS)

Neck, R.; Blueschke-Nikolaeva, V.; Blueschke, D.

2017-06-01

In this paper, we study the effects of scrap values on the solutions of optimal control problems with finite time horizon. We show how to include a scrap value, either for the state variables or for the state and the control variables, in the OPTCON2 algorithm for the optimal control of dynamic economic systems. We ask whether the introduction of a scrap value can serve as a substitute for an infinite horizon in economic policy optimization problems where the latter option is not available. Using a simple numerical macroeconomic model, we demonstrate that the introduction of a scrap value cannot induce control policies which can be expected for problems with an infinite time horizon.

Complex collaborative problem-solving processes in mission control.

PubMed

Fiore, Stephen M; Wiltshire, Travis J; Oglesby, James M; O'Keefe, William S; Salas, Eduardo

2014-04-01

NASA's Mission Control Center (MCC) is responsible for control of the International Space Station (ISS), which includes responding to problems that obstruct the functioning of the ISS and that may pose a threat to the health and well-being of the flight crew. These problems are often complex, requiring individuals, teams, and multiteam systems, to work collaboratively. Research is warranted to examine individual and collaborative problem-solving processes in this context. Specifically, focus is placed on how Mission Control personnel-each with their own skills and responsibilities-exchange information to gain a shared understanding of the problem. The Macrocognition in Teams Model describes the processes that individuals and teams undertake in order to solve problems and may be applicable to Mission Control teams. Semistructured interviews centering on a recent complex problem were conducted with seven MCC professionals. In order to assess collaborative problem-solving processes in MCC with those predicted by the Macrocognition in Teams Model, a coding scheme was developed to analyze the interview transcriptions. Findings are supported with excerpts from participant transcriptions and suggest that team knowledge-building processes accounted for approximately 50% of all coded data and are essential for successful collaborative problem solving in mission control. Support for the internalized and externalized team knowledge was also found (19% and 20%, respectively). The Macrocognition in Teams Model was shown to be a useful depiction of collaborative problem solving in mission control and further research with this as a guiding framework is warranted.

Reducing Child Problem Behaviors and Improving Teacher-Child Interactions and Relationships: A Randomized Controlled Trial of Best in Class

ERIC Educational Resources Information Center

Sutherland, Kevin S.; Conroy, Maureen A.; Algina, James; Ladwig, Crystal; Jesse, Gabriel; Gyure, Maria

2018-01-01

Research has consistently linked early problem behavior with later adjustment problems, including antisocial behavior, learning problems and risk for the development of emotional/behavioral disorders (EBDs). Researchers have focused upon developing effective intervention programs for young children who arrive in preschool exhibiting chronic…

Sleep problems and temperament in young children with Down syndrome and typically developing controls.

PubMed

Lukowski, A F; Milojevich, H M

2017-03-01

Although group differences have been found between children with Down syndrome (DS) and typically developing (TD) children when considering sleep problems and temperament independently, none of the research conducted to date has examined sleep-temperament associations in children with DS. The present research was conducted to determine (1) whether the sleep problems experienced by children with DS are associated with temperament or (2) if the demonstrated relations between sleep and temperament differ from those that are observed in TD children. The present study included examination of relations between parent-reported sleep problems and temperament in 19 children with DS and 20 TD controls matched on developmental age. The results revealed group differences in temperament and sleep problems. Mediation models indicated that temperament (effortful control and inhibitory control) mediated the association between group and sleep problems; sleep problems also mediated the association between group and temperament (effortful and inhibitory control). Findings indicated that sleep problems may serve as both cause and consequence of variability in effortful and inhibitory control and provide insight as to future experimental studies that should be conducted to better elucidate these relations. © 2016 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

ORACLS: A system for linear-quadratic-Gaussian control law design

NASA Technical Reports Server (NTRS)

Armstrong, E. S.

1978-01-01

A modern control theory design package (ORACLS) for constructing controllers and optimal filters for systems modeled by linear time-invariant differential or difference equations is described. Numerical linear-algebra procedures are used to implement the linear-quadratic-Gaussian (LQG) methodology of modern control theory. Algorithms are included for computing eigensystems of real matrices, the relative stability of a matrix, factored forms for nonnegative definite matrices, the solutions and least squares approximations to the solutions of certain linear matrix algebraic equations, the controllability properties of a linear time-invariant system, and the steady state covariance matrix of an open-loop stable system forced by white noise. Subroutines are provided for solving both the continuous and discrete optimal linear regulator problems with noise free measurements and the sampled-data optimal linear regulator problem. For measurement noise, duality theory and the optimal regulator algorithms are used to solve the continuous and discrete Kalman-Bucy filter problems. Subroutines are also included which give control laws causing the output of a system to track the output of a prescribed model.

Pancreatic Diseases

MedlinePlus

The pancreas is a gland behind your stomach and in front of your spine. It produces juices that help ... help control blood sugar levels. Problems with the pancreas can lead to many health problems. These include ...

Solution of elastic-plastic stress analysis problems by the p-version of the finite element method

NASA Technical Reports Server (NTRS)

Szabo, Barna A.; Actis, Ricardo L.; Holzer, Stefan M.

1993-01-01

The solution of small strain elastic-plastic stress analysis problems by the p-version of the finite element method is discussed. The formulation is based on the deformation theory of plasticity and the displacement method. Practical realization of controlling discretization errors for elastic-plastic problems is the main focus. Numerical examples which include comparisons between the deformation and incremental theories of plasticity under tight control of discretization errors are presented.

Effortful Control, Behavior Problems and Peer Relations: What Predicts Academic Adjustment in Kindergarteners from Low-income Families?

PubMed Central

Morris, Amanda Sheffield; John, Aesha; Halliburton, Amy L.; Morris, Michael D. S.; Robinson, Lara R.; Myers, Sonya S.; Aucoin, Katherine J.; Keyes, Angela W.; Terranova, Andrew

2013-01-01

This study examined the role of effortful control, behavior problems, and peer relations in the academic adjustment of 74 kindergarten children from primarily low-income families using a short-term longitudinal design. Teachers completed standardized measures of children’s effortful control, internalizing and externalizing problems, school readiness, and academic skills. Children participated in a sociometric interview to assess peer relations. Research Findings: Correlational analyses indicate that children’s effortful control, behavior problems in school, and peer relations are associated with academic adjustment variables at the end of the school year, including school readiness, reading skills, and math skills. Results of regression analyses indicate that household income and children’s effortful control primarily account for variation in children’s academic adjustment. The associations between children’s effortful control and academic adjustment did not vary across sex of the child or ethnicity. Mediational analyses indicate an indirect effect of effortful control on school readiness, through children’s internalizing problems. Practice or Policy: Effortful control emerged as a strong predictor of academic adjustment among kindergarten children from low-income families. Strategies for enhancing effortful control and school readiness among low-income children are discussed. PMID:24163572

Supercomputer optimizations for stochastic optimal control applications

NASA Technical Reports Server (NTRS)

Chung, Siu-Leung; Hanson, Floyd B.; Xu, Huihuang

1991-01-01

Supercomputer optimizations for a computational method of solving stochastic, multibody, dynamic programming problems are presented. The computational method is valid for a general class of optimal control problems that are nonlinear, multibody dynamical systems, perturbed by general Markov noise in continuous time, i.e., nonsmooth Gaussian as well as jump Poisson random white noise. Optimization techniques for vector multiprocessors or vectorizing supercomputers include advanced data structures, loop restructuring, loop collapsing, blocking, and compiler directives. These advanced computing techniques and superconducting hardware help alleviate Bellman's curse of dimensionality in dynamic programming computations, by permitting the solution of large multibody problems. Possible applications include lumped flight dynamics models for uncertain environments, such as large scale and background random aerospace fluctuations.

Multi Objective Controller Design for Linear System via Optimal Interpolation

NASA Technical Reports Server (NTRS)

Ozbay, Hitay

1996-01-01

We propose a methodology for the design of a controller which satisfies a set of closed-loop objectives simultaneously. The set of objectives consists of: (1) pole placement, (2) decoupled command tracking of step inputs at steady-state, and (3) minimization of step response transients with respect to envelope specifications. We first obtain a characterization of all controllers placing the closed-loop poles in a prescribed region of the complex plane. In this characterization, the free parameter matrix Q(s) is to be determined to attain objectives (2) and (3). Objective (2) is expressed as determining a Pareto optimal solution to a vector valued optimization problem. The solution of this problem is obtained by transforming it to a scalar convex optimization problem. This solution determines Q(O) and the remaining freedom in choosing Q(s) is used to satisfy objective (3). We write Q(s) = (l/v(s))bar-Q(s) for a prescribed polynomial v(s). Bar-Q(s) is a polynomial matrix which is arbitrary except that Q(O) and the order of bar-Q(s) are fixed. Obeying these constraints bar-Q(s) is now to be 'shaped' to minimize the step response characteristics of specific input/output pairs according to the maximum envelope violations. This problem is expressed as a vector valued optimization problem using the concept of Pareto optimality. We then investigate a scalar optimization problem associated with this vector valued problem and show that it is convex. The organization of the report is as follows. The next section includes some definitions and preliminary lemmas. We then give the problem statement which is followed by a section including a detailed development of the design procedure. We then consider an aircraft control example. The last section gives some concluding remarks. The Appendix includes the proofs of technical lemmas, printouts of computer programs, and figures.

Using Linear Models to Simultaneously Analyze a Solomon Four Group Design.

ERIC Educational Resources Information Center

Williams, John D.; Newman, Isadore

Problems associated with the analysis of data collected using the Solomon Four Group Design are discussed. The design includes an experimental group and a control group that have been pretested and posttested, and an experimental and a control group that have been posttested only. A sample problem is approached in three different ways. First, the…

Elements of active vibration control for rotating machinery

NASA Technical Reports Server (NTRS)

Ulbrich, Heinz

1990-01-01

The success or failure of active vibration control is determined by the availability of suitable actuators, modeling of the entire system including all active elements, positioning of the actuators and sensors, and implementation of problem-adapted control concepts. All of these topics are outlined and their special problems are discussed in detail. Special attention is given to efficient modeling of systems, especially for considering the active elements. Finally, design methods for and the application of active vibration control on rotating machinery are demonstrated by several real applications.

Dog Feces: A Public Health and Environmental Problem

ERIC Educational Resources Information Center

Marron, J. A.; Senn, Charles L.

1974-01-01

This article reports that dog feces are a problem because they are capable of transmitting diseases, as well as acting as a breeding place for for fly larvae and food for rats. Studies included in the article indicate the need for public education and for an effective control program. Bibliography included. (MA)

Linear Matrix Inequality Method for a Quadratic Performance Index Minimization Problem with a class of Bilinear Matrix Inequality Conditions

NASA Astrophysics Data System (ADS)

Tanemura, M.; Chida, Y.

2016-09-01

There are a lot of design problems of control system which are expressed as a performance index minimization under BMI conditions. However, a minimization problem expressed as LMIs can be easily solved because of the convex property of LMIs. Therefore, many researchers have been studying transforming a variety of control design problems into convex minimization problems expressed as LMIs. This paper proposes an LMI method for a quadratic performance index minimization problem with a class of BMI conditions. The minimization problem treated in this paper includes design problems of state-feedback gain for switched system and so on. The effectiveness of the proposed method is verified through a state-feedback gain design for switched systems and a numerical simulation using the designed feedback gains.

The Voyager spacecraft /James Watt International Gold Medal Lecture/

NASA Technical Reports Server (NTRS)

Heacock, R. L.

1980-01-01

The Voyager Project background is reviewed with emphasis on selected features of the Voyager spacecraft. Investigations by the Thermo-electric Outer Planets Spacecraft Project are discussed, including trajectories, design requirements, and the development of a Self Test and Repair computer, and a Computer Accessed Telemetry System. The design and configuration of the spacecraft are described, including long range communications, attitude control, solar independent power, sequencing and control data handling, and spacecraft propulsion. The development program, maintained by JPL, experienced a variety of problems such as design deficiencies, and process control and manufacturing problems. Finally, the spacecraft encounter with Jupiter is discussed, and expectations for the Saturn encounter are expressed.

Lexical Problems in Large Distributed Information Systems.

ERIC Educational Resources Information Center

Berkovich, Simon Ya; Shneiderman, Ben

1980-01-01

Suggests a unified concept of a lexical subsystem as part of an information system to deal with lexical problems in local and network environments. The linguistic and control functions of the lexical subsystems in solving problems for large computer systems are described, and references are included. (Author/BK)

Beam wavefront and farfield control for ICF laser driver

NASA Astrophysics Data System (ADS)

Dai, Wanjun; Deng, Wu; Zhang, Xin; Jiang, Xuejun; Zhang, Kun; Zhou, Wei; Zhao, Junpu; Hu, Dongxia

2010-10-01

Five main problems of beam wavefront and farfield control in ICF laser driver are synthetically discussed, including control requirements, beam propagation principle, distortions source control, system design and adjustment optimization, active wavefront correction technology. We demonstrate that beam can be propagated well and the divergence angle of the TIL pulses can be improved to less than 60μrad with solving these problems, which meets the requirements of TIL. The results can provide theoretical and experimental support for wavefront and farfield control designing requirements of the next large scale ICF driver.

Marine geodesy a multipurpose approach to solve oceanic problems. [including submersible navigation under iced seas, demarcation and determination of boundaries in deep ocean, tsunamis, and ecology

NASA Technical Reports Server (NTRS)

Saxena, N.

1974-01-01

Various current and future problem areas of marine geodesy are identified. These oceanic problem areas are highly diversified and include submersible navigation under ice seas, demarcation and determination of boundaries in deep ocean, tsunamis, ecology, etc., etc. Their achieved as well as desired positional accuracy estimates, based upon publications and discussions, are also given. A multipurpose approach to solve these problems is described. An optimum configuration of an ocean-bottom control-net unit is provided.

Issues in human/computer control of dexterous remote hands

NASA Technical Reports Server (NTRS)

Salisbury, K.

1987-01-01

Much research on dexterous robot hands has been aimed at the design and control problems associated with their autonomous operation, while relatively little research has addressed the problem of direct human control. It is likely that these two modes can be combined in a complementary manner yielding more capability than either alone could provide. While many of the issues in mixed computer/human control of dexterous hands parallel those found in supervisory control of traditional remote manipulators, the unique geometry and capabilities of dexterous hands pose many new problems. Among these are the control of redundant degrees of freedom, grasp stabilization and specification of non-anthropomorphic behavior. An overview is given of progress made at the MIT AI Laboratory in control of the Salisbury 3 finger hand, including experiments in grasp planning and manipulation via controlled slip. It is also suggested how we might introduce human control into the process at a variety of functional levels.

Shape determination and control for large space structures

NASA Technical Reports Server (NTRS)

Weeks, C. J.

1981-01-01

An integral operator approach is used to derive solutions to static shape determination and control problems associated with large space structures. Problem assumptions include a linear self-adjoint system model, observations and control forces at discrete points, and performance criteria for the comparison of estimates or control forms. Results are illustrated by simulations in the one dimensional case with a flexible beam model, and in the multidimensional case with a finite model of a large space antenna. Modal expansions for terms in the solution algorithms are presented, using modes from the static or associated dynamic mode. These expansions provide approximated solutions in the event that a used form analytical solution to the system boundary value problem is not available.

What can posturography tell us about vestibular function?

NASA Technical Reports Server (NTRS)

Black, F. O.

2001-01-01

Patients with balance disorders want answers to the following basic questions: (1) What is causing my problem? and (2) What can be done about my problem? Information to fully answer these questions must include status of both sensory and motor components of the balance control systems. Computerized dynamic posturography (CDP) provides quantitative assessment of both sensory and motor components of postural control along with how the sensory inputs to the brain interact. This paper reviews the scientific basis and clinical applications of CDP. Specifically, studies describing the integration of vestibular inputs with other sensory systems for postural control are briefly summarized. Clinical applications, including assessment, rehabilitation, and management are presented. Effects of aging on postural control along with prevention and management strategies are discussed.

Quality Control in Title I Evaluation: Problems and Approaches.

ERIC Educational Resources Information Center

Hansen, Joe B.

Educational program evalaution is subject to many difficulties. Problems with evaluation include such conceptual problems as: (1) understanding of decisions to be made; (2) adequate definition; (3) consensus on values and criteria; (4) coordination among administrative levels; and (5) use of an appropriate evaluation model. Technical problems…

Social problem-solving, perceived stress, negative life events, depression and life satisfaction in psoriasis.

PubMed

Eskin, M; Savk, E; Uslu, M; Küçükaydoğan, N

2014-11-01

Psoriasis is a chronic dermatosis which may cause significant impairment of the patient's quality of life. The purpose of this study was to investigate the social problem-solving skills, perceived stress, negative life events, depression and life satisfaction in psoriasis patients. Data were gathered by means of questionnaires and clinical evaluations from 51 psoriatic patients and 51 matched healthy controls. Average disease duration was 16.47 years and average Psoriasis Area and Severity Index score was 3.67. Compared with the controls, the patients displayed lower social problem-solving skills. They displayed higher negative problem orientation and impulsive-careless problem-solving style scores than the controls. Patients tended also to show more avoidant problem-solving style and lower life satisfaction than controls. There was no difference between psoriatic patients and controls in terms of depression, perceived stress and negative life events. Higher social problem-solving skills were associated with lower depression, perceived stress and fewer numbers of negative life events but higher level of life satisfaction. The patient group largely included mild and moderate psoriatic cases. The findings of the study suggest that problem-solving training or therapy may be a suitable option for alleviating levels of psychological distress in patients suffering from psoriasis. © 2014 European Academy of Dermatology and Venereology.

Proceedings of the 8th Annual Conference on Manual Control

NASA Technical Reports Server (NTRS)

Pew, R. W.

1972-01-01

The volume presents recent developments in the field of manual control theory and applications. The papers give analytical methods as well as examples of the important interplay between man and machine, such as how man controls and stabilizes machine dynamics, and how machines extend man's capability. Included in the broad range of subjects are procedures to evaluate and identify display systems, controllers, manipulators, human operators, aircraft, and non-flying vehicles. Of particular interest is the continuing trend of applying control theory to problems in medicine and psychology, as well as to problems in vehicle control.

Dynamic analysis of space structures including elastic, multibody, and control behavior

NASA Technical Reports Server (NTRS)

Pinson, Larry; Soosaar, Keto

1989-01-01

The problem is to develop analysis methods, modeling stategies, and simulation tools to predict with assurance the on-orbit performance and integrity of large complex space structures that cannot be verified on the ground. The problem must incorporate large reliable structural models, multi-body flexible dynamics, multi-tier controller interaction, environmental models including 1g and atmosphere, various on-board disturbances, and linkage to mission-level performance codes. All areas are in serious need of work, but the weakest link is multi-body flexible dynamics.

Robust Feedback Control of Flow Induced Structural Radiation of Sound

NASA Technical Reports Server (NTRS)

Heatwole, Craig M.; Bernhard, Robert J.; Franchek, Matthew A.

1997-01-01

A significant component of the interior noise of aircraft and automobiles is a result of turbulent boundary layer excitation of the vehicular structure. In this work, active robust feedback control of the noise due to this non-predictable excitation is investigated. Both an analytical model and experimental investigations are used to determine the characteristics of the flow induced structural sound radiation problem. The problem is shown to be broadband in nature with large system uncertainties associated with the various operating conditions. Furthermore the delay associated with sound propagation is shown to restrict the use of microphone feedback. The state of the art control methodologies, IL synthesis and adaptive feedback control, are evaluated and shown to have limited success for solving this problem. A robust frequency domain controller design methodology is developed for the problem of sound radiated from turbulent flow driven plates. The control design methodology uses frequency domain sequential loop shaping techniques. System uncertainty, sound pressure level reduction performance, and actuator constraints are included in the design process. Using this design method, phase lag was added using non-minimum phase zeros such that the beneficial plant dynamics could be used. This general control approach has application to lightly damped vibration and sound radiation problems where there are high bandwidth control objectives requiring a low controller DC gain and controller order.

Theory of Planned Behavior including self-stigma and perceived barriers explain help-seeking behavior for sexual problems in Iranian women suffering from epilepsy.

PubMed

Lin, Chung-Ying; Oveisi, Sonia; Burri, Andrea; Pakpour, Amir H

2017-03-01

To apply the Theory of Planned Behavior (TPB) and the two additional concepts self-stigma and perceived barriers to the help-seeking behavior for sexual problems in women with epilepsy. In this 18-month follow-up study, TPB elements, including attitude, subjective norm, perceived behavioral control, and behavioral intention along with self-stigma and perceived barriers in seeking help for sexual problems were assessed in n=818 women with epilepsy (94.0% aged ≤40years). The basic TPB model (model 1) and the TPB model additionally including self-stigma and perceived barriers (Model 2) were analyzed using structural equation modeling (SEM). Both SEM models showed satisfactory model fits. According to model, attitude, subjective norms, perceived behavioral control, and intention explained 63.1% of the variance in help-seeking behavior. Variance was slightly higher (64.5%) when including self-stigma and perceived barriers (model 2). In addition, the fit indices of the models were better highlighting the importance of self-stigma and perceived barriers in help-seeking behavior for sexual problems. Theory of Planned Behavior is useful in explaining help-seeking behavior for sexual problems in women with epilepsy. Self-stigma and perceived barriers are additional factors that should be considered in future interventions aiming to adopt TPB to improve help-seeking behavior for sexual problems. Copyright © 2017 Elsevier Inc. All rights reserved.

Compulsive Gambling

MedlinePlus

Many people enjoy gambling, whether it's betting on a horse or playing poker on the Internet. Most people who gamble don't have a problem, but some lose control of their gambling. Signs of problem gambling include Always thinking about ...

Combining a Multi-Agent System and Communication Middleware for Smart Home Control: A Universal Control Platform Architecture

PubMed Central

Zheng, Song; Zhang, Qi; Zheng, Rong; Huang, Bi-Qin; Song, Yi-Lin; Chen, Xin-Chu

2017-01-01

In recent years, the smart home field has gained wide attention for its broad application prospects. However, families using smart home systems must usually adopt various heterogeneous smart devices, including sensors and devices, which makes it more difficult to manage and control their home system. How to design a unified control platform to deal with the collaborative control problem of heterogeneous smart devices is one of the greatest challenges in the current smart home field. The main contribution of this paper is to propose a universal smart home control platform architecture (IAPhome) based on a multi-agent system and communication middleware, which shows significant adaptability and advantages in many aspects, including heterogeneous devices connectivity, collaborative control, human-computer interaction and user self-management. The communication middleware is an important foundation to design and implement this architecture which makes it possible to integrate heterogeneous smart devices in a flexible way. A concrete method of applying the multi-agent software technique to solve the integrated control problem of the smart home system is also presented. The proposed platform architecture has been tested in a real smart home environment, and the results indicate that the effectiveness of our approach for solving the collaborative control problem of different smart devices. PMID:28926957

Combining a Multi-Agent System and Communication Middleware for Smart Home Control: A Universal Control Platform Architecture.

PubMed

Zheng, Song; Zhang, Qi; Zheng, Rong; Huang, Bi-Qin; Song, Yi-Lin; Chen, Xin-Chu

2017-09-16

In recent years, the smart home field has gained wide attention for its broad application prospects. However, families using smart home systems must usually adopt various heterogeneous smart devices, including sensors and devices, which makes it more difficult to manage and control their home system. How to design a unified control platform to deal with the collaborative control problem of heterogeneous smart devices is one of the greatest challenges in the current smart home field. The main contribution of this paper is to propose a universal smart home control platform architecture (IAPhome) based on a multi-agent system and communication middleware, which shows significant adaptability and advantages in many aspects, including heterogeneous devices connectivity, collaborative control, human-computer interaction and user self-management. The communication middleware is an important foundation to design and implement this architecture which makes it possible to integrate heterogeneous smart devices in a flexible way. A concrete method of applying the multi-agent software technique to solve the integrated control problem of the smart home system is also presented. The proposed platform architecture has been tested in a real smart home environment, and the results indicate that the effectiveness of our approach for solving the collaborative control problem of different smart devices.

Parenting Stress and Emotional/Behavioral Problems in Adolescents with Primary Headache.

PubMed

Operto, Francesca Felicia; Craig, Francesco; Peschechera, Antonia; Mazza, Roberta; Lecce, Paola Alessandra; Margari, Lucia

2017-01-01

Primary headache is a frequent and disabling disorder, common among children and adolescents, and it is a painful syndrome often accompanied by functional impairment and associated with emotional and behavior problems. The aim of this study was to investigate parenting stress and emotional/behavioral problems in adolescents affected by primary headache compared with healthy adolescents. The study population consisted of 35 adolescents and a control group of 23 healthy subjects. The assessment included the administration of clinical standardized scales such as Parent Stress Index-Short Form, Pediatric Migraine Disability Assessment Score Questionnaire, and Child Behavior Checklist (CBCL). Headache group and control group did not differ in terms of parenting stress ( p  = 0.29). On the contrary, headache group showed more internalizing problems ( p  = 0.023), affective problems ( p  = 0.01), anxious ( p  = 0.001), and somatic complaints ( p  < 0.001) compared with control group. In addition, we found a significant correlation between PSI domains and specific CBCL subscales in the headache group. The findings emphasize the need for expanded intervention in the clinical treatment of pediatric headache, a treatment that may also include the family members. Further research is needed.

VASP- VARIABLE DIMENSION AUTOMATIC SYNTHESIS PROGRAM

NASA Technical Reports Server (NTRS)

White, J. S.

1994-01-01

VASP is a variable dimension Fortran version of the Automatic Synthesis Program, ASP. The program is used to implement Kalman filtering and control theory. Basically, it consists of 31 subprograms for solving most modern control problems in linear, time-variant (or time-invariant) control systems. These subprograms include operations of matrix algebra, computation of the exponential of a matrix and its convolution integral, and the solution of the matrix Riccati equation. The user calls these subprograms by means of a FORTRAN main program, and so can easily obtain solutions to most general problems of extremization of a quadratic functional of the state of the linear dynamical system. Particularly, these problems include the synthesis of the Kalman filter gains and the optimal feedback gains for minimization of a quadratic performance index. VASP, as an outgrowth of the Automatic Synthesis Program, has the following improvements: more versatile programming language; more convenient input/output format; some new subprograms which consolidate certain groups of statements that are often repeated; and variable dimensioning. The pertinent difference between the two programs is that VASP has variable dimensioning and more efficient storage. The documentation for the VASP program contains a VASP dictionary and example problems. The dictionary contains a description of each subroutine and instructions on its use. The example problems include dynamic response, optimal control gain, solution of the sampled data matrix Riccati equation, matrix decomposition, and a pseudo-inverse of a matrix. This program is written in FORTRAN IV and has been implemented on the IBM 360. The VASP program was developed in 1971.

[Emotional regulation and motivation in children with ADHD].

PubMed

Høvik, Marie Farstad; Plessen, Kerstin J

2010-12-02

Impaired cognitive control functions have long been regarded as the main problem in the development of Attention-Deficit/Hyperactivity Disorder (ADHD). A more recent model emphasizes the importance of emotional and motivational problems. We have reviewed the evidence for this model, which may have important implications for clinical practice. The article is based on literature identified through a non-systematic search in PubMed. Although limited research was carried out in this topic earlier, studies are currently emerging. Persons with ADHD react differently than controls on tasks that include rewards and on tasks that stress their capacity to regulate emotions. Abnormal signals during examination with electroencephalography (EEG) and anatomical and functional magnetic resonance imaging (fMRI) reflect problems with emotional regulation in patients with ADHD. Neurobiological research supports a model that includes emotional and motivational problems in the development of ADHD. Increased knowledge about emotional and motivational problems may improve treatment of these patients through development of more individually adapted therapy.

Recent experience in simultaneous control-structure optimization

NASA Technical Reports Server (NTRS)

Salama, M.; Ramaker, R.; Milman, M.

1989-01-01

To show the feasibility of simultaneous optimization as design procedure, low order problems were used in conjunction with simple control formulations. The numerical results indicate that simultaneous optimization is not only feasible, but also advantageous. Such advantages come at the expense of introducing complexities beyond those encountered in structure optimization alone, or control optimization alone. Examples include: larger design parameter space, optimization may combine continuous and combinatoric variables, and the combined objective function may be nonconvex. Future extensions to include large order problems, more complex objective functions and constraints, and more sophisticated control formulations will require further research to ensure that the additional complexities do not outweigh the advantages of simultaneous optimization. Some areas requiring more efficient tools than currently available include: multiobjective criteria and nonconvex optimization. Efficient techniques to deal with optimization over combinatoric and continuous variables, and with truncation issues for structure and control parameters of both the model space as well as the design space need to be developed.

Slew maneuvers of Spacecraft Control Laboratory Experiment (SCOLE)

NASA Technical Reports Server (NTRS)

Kakad, Yogendra P.

1992-01-01

This is the final report on the dynamics and control of slew maneuvers of the Spacecraft Control Laboratory Experiment (SCOLE) test facility. The report documents the basic dynamical equation derivations for an arbitrary large angle slew maneuver as well as the basic decentralized slew maneuver control algorithm. The set of dynamical equations incorporate rigid body slew maneuver and three dimensional vibrations of the complete assembly comprising the rigid shuttle, the flexible beam, and the reflector with an offset mass. The analysis also includes kinematic nonlinearities of the entire assembly during the maneuver and the dynamics of the interactions between the rigid shuttle and the flexible appendage. The equations are simplified and evaluated numerically to include the first ten flexible modes to yield a model for designing control systems to perform slew maneuvers. The control problem incorporates the nonlinear dynamical equations and is expressed in terms of a two point boundary value problem.

[Actuator placement for active sound and vibration control

NASA Technical Reports Server (NTRS)

1997-01-01

Two refereed journal publications and ten talks given at conferences, seminars, and colloquia resulted from research supported by NASA. They are itemized in this report. The two publications were entitled "Reactive Tabu and Search Sensor Selection in Active Structural Acoustic Control Problems" and "Quelling Cabin Noise in Turboprop Aircraft via Active Control." The conference presentations covered various aspects of actuator placement, including location problems, for active sound and vibration control of cylinders, of commuter jets, of propeller driven or turboprop aircraft, and for quelling aircraft cabin or interior noise.

Conflict Management in "Ad Hoc" Problem-Solving Groups: A Preliminary Investigation.

ERIC Educational Resources Information Center

Wallace, Les; Baxter, Leslie

Full study of small group communication must include consideration of task and socio-emotional dimensions, especially in relation to group problem solving. Thirty small groups were tested for their reactions in various "ad hoc" conflict resolution situations. Instructions to the groups were (1) no problem-solving instructions (control),…

Modern Problems: Sociology Units. An Experimental Program for Grade 12.

ERIC Educational Resources Information Center

Carlson, Marshall; Fennig, Lois

GRADES OR AGES: Grade 12. SUBJECT MATTER: Sociology; modern problems. ORGANIZATION AND PHYSICAL APPEARANCE: The guide contains two units, one on the problems of minority groups and the other on social pathology. Sub-sections of unit 2 include crime and criminals, criminal investigation, gun control, U.S. criminal law, criminal procedure,…

The Effect of Contextual and Conceptual Rewording on Mathematical Problem-Solving Performance

ERIC Educational Resources Information Center

Haghverdi, Majid; Wiest, Lynda R.

2016-01-01

This study shows how separate and combined contextual and conceptual problem rewording can positively influence student performance in solving mathematical word problems. Participants included 80 seventh-grade Iranian students randomly assigned in groups of 20 to three experimental groups involving three types of rewording and a control group. All…

Optimization of controlled processes in combined-cycle plant (new developments and researches)

NASA Astrophysics Data System (ADS)

Tverskoy, Yu S.; Muravev, I. K.

2017-11-01

All modern complex technical systems, including power units of TPP and nuclear power plants, work in the system-forming structure of multifunctional APCS. The development of the modern APCS mathematical support allows bringing the automation degree to the solution of complex optimization problems of equipment heat-mass-exchange processes in real time. The difficulty of efficient management of a binary power unit is related to the need to solve jointly at least three problems. The first problem is related to the physical issues of combined-cycle technologies. The second problem is determined by the criticality of the CCGT operation to changes in the regime and climatic factors. The third problem is related to a precise description of a vector of controlled coordinates of a complex technological object. To obtain a joint solution of this complex of interconnected problems, the methodology of generalized thermodynamic analysis, methods of the theory of automatic control and mathematical modeling are used. In the present report, results of new developments and studies are shown. These results allow improving the principles of process control and the automatic control systems structural synthesis of power units with combined-cycle plants that provide attainable technical and economic efficiency and operational reliability of equipment.

Direct heuristic dynamic programming for damping oscillations in a large power system.

PubMed

Lu, Chao; Si, Jennie; Xie, Xiaorong

2008-08-01

This paper applies a neural-network-based approximate dynamic programming method, namely, the direct heuristic dynamic programming (direct HDP), to a large power system stability control problem. The direct HDP is a learning- and approximation-based approach to addressing nonlinear coordinated control under uncertainty. One of the major design parameters, the controller learning objective function, is formulated to directly account for network-wide low-frequency oscillation with the presence of nonlinearity, uncertainty, and coupling effect among system components. Results include a novel learning control structure based on the direct HDP with applications to two power system problems. The first case involves static var compensator supplementary damping control, which is used to provide a comprehensive evaluation of the learning control performance. The second case aims at addressing a difficult complex system challenge by providing a new solution to a large interconnected power network oscillation damping control problem that frequently occurs in the China Southern Power Grid.

A Sequential Linear Quadratic Approach for Constrained Nonlinear Optimal Control with Adaptive Time Discretization and Application to Higher Elevation Mars Landing Problem

NASA Astrophysics Data System (ADS)

Sandhu, Amit

A sequential quadratic programming method is proposed for solving nonlinear optimal control problems subject to general path constraints including mixed state-control and state only constraints. The proposed algorithm further develops on the approach proposed in [1] with objective to eliminate the use of a high number of time intervals for arriving at an optimal solution. This is done by introducing an adaptive time discretization to allow formation of a desirable control profile without utilizing a lot of intervals. The use of fewer time intervals reduces the computation time considerably. This algorithm is further used in this thesis to solve a trajectory planning problem for higher elevation Mars landing.

Action-based language: a theory of language acquisition, comprehension, and production.

PubMed

Glenberg, Arthur M; Gallese, Vittorio

2012-07-01

Evolution and the brain have done a marvelous job solving many tricky problems in action control, including problems of learning, hierarchical control over serial behavior, continuous recalibration, and fluency in the face of slow feedback. Given that evolution tends to be conservative, it should not be surprising that these solutions are exploited to solve other tricky problems, such as the design of a communication system. We propose that a mechanism of motor control, paired controller/predictor models, has been exploited for language learning, comprehension, and production. Our account addresses the development of grammatical regularities and perspective, as well as how linguistic symbols become meaningful through grounding in perception, action, and emotional systems. Copyright © 2011 Elsevier Srl. All rights reserved.

A meta-analytic review of psychological treatments for tinnitus.

PubMed

Andersson, G; Lyttkens, L

1999-08-01

Meta-analysis is a technique of combining results from different trials in order to obtain estimates of effects across studies. Meta-analysis has, as yet, rarely been used in audiological research. The aim of this paper was to conduct a meta-analysis on psychological treatment of tinnitus. The outcomes of 18 studies, including a total of 24 samples and up to 700 subjects, were included and coded. Included were studies on cognitive/cognitive-behavioural treatment, relaxation, hypnosis, biofeedback, educational sessions and problem-solving. Effect sizes for perceived tinnitus loudness, annoyance, negative affect (e.g. depression) and sleep problems were calculated for randomized controlled studies, pre-post-treatment design studies and follow-up results. Results showed strong to moderate effects on tinnitus annoyance for controlled studies (d = 0.86), pre-post designs (d = 0.5) and at follow-up (d = 0.48). Results on tinnitus loudness were weaker and disappeared at follow-up. Lower effect sizes were also obtained for measures of negative affect and sleep problems. Exploratory analyses revealed that cognitive-behavioural treatments were more effective on ratings of annoyance in the controlled studies. It is concluded that psychological treatment for tinnitus is effective, but that aspects such as depression and sleep problems may need to be targeted in future studies.

Parenting and children's externalizing problems in substance-abusing families.

PubMed

Stanger, Catherine; Dumenci, Levent; Kamon, Jody; Burstein, Marcy

2004-09-01

This study tested associations in path models among positive and negative parenting and children's rule-breaking behavior, aggressive and oppositional behavior, and attention problems for families with a drug-dependent parent. A structural model tested relations between parenting and children's externalizing problems for 251 families with 399 children between the ages of 6 and 18, controlling for nonindependence of ratings at the family level. The model also tested potential moderators, including child age, gender, and ethnicity (White vs. other), and caregiver gender (families with a female substance-abusing caregiver vs. families with a male substance-abusing caregiver). Results indicated that caregiver ratings of monitoring predicted rule-breaking behavior and use of inconsistent discipline predicted ratings of all 3 externalizing syndromes, after controlling parenting and externalizing problems for the effects of the moderators and after controlling significant relations among types of parenting and types of externalizing problems.

Perceived control moderates the relationship between social capital and binge drinking: longitudinal findings from the Montreal Neighborhood Networks and Health Aging (MoNNET-HA) panel.

PubMed

Child, Stephanie; Stewart, Steven; Moore, Spencer

2017-02-01

Cross-sectional research suggests social capital has negative consequences for problem drinking behaviors. Previous studies have suggested psychosocial resources, including perceived control, may buffer this association. Little research has examined whether such relationships persist longitudinally. Random effects models examined between-person relationships among problem drinking, social capital, and perceived control, and whether perceived control moderated the relationship between social capital and drinking. Fixed effects models assessed whether social capital and perceived control were related to changes in problem drinking. Greater network capital and generalized trust predicted higher odds of binge drinking (RR = 1.08; 95% CI = 1.03-1.12 and RR = 1.23; 95% CI = 1.03-1.48, respectively). Perceived control moderated the positive association of network capital with binge drinking (RR = 0.91; 95% CI = 0.87-0.96). The present findings support previous notions about the complex role of social capital on health, and offer new insights on the role of perceived control on problem drinking. Copyright © 2016 Elsevier Inc. All rights reserved.

Chemistry and the Internal Combustion Engine II: Pollution Problems.

ERIC Educational Resources Information Center

Hunt, C. B.

1979-01-01

Discusses pollution problems which arise from the use of internal combustion (IC) engines in the United Kingdom (UK). The IC engine exhaust emissions, controlling IC engine pollution in the UK, and some future developments are also included. (HM)

From Habits to Self-Regulation: How Do We Change?

PubMed Central

Gianessi, Carol A.

2012-01-01

The Yale Cognitive Science department hosted the conference “From Habits to Self-Regulation: How Do We Change?” on November 4 and 5, 2011, to showcase current research on self-control in cognitive science, psychology, and neuroscience. The conference included a panel discussion by four philosophers who gave context for the scope and limitations of research on self-control. The common theme concerning the best method to attain lasting change included becoming aware of what one wants to change, increasing commitment to the goal of change, and imagining all of the potential problems and solutions to those problems. PMID:22737058

Everyday Experiences of Memory Problems and Control: The Adaptive Role of Selective Optimization with Compensation in the Context of Memory Decline

PubMed Central

Hahn, Elizabeth A.; Lachman, Margie E.

2014-01-01

The present study examined the role of long-term working memory decline in the relationship between everyday experiences of memory problems and perceived control, and we also considered whether the use of accommodative strategies [selective optimization with compensation (SOC)] would be adaptive. The study included Boston-area participants (n=103) from the Midlife in the United States study (MIDUS) who completed two working memory assessments over ten years and weekly diaries following Time 2. In adjusted multi-level analyses, greater memory decline and lower general perceived control were associated with more everyday memory problems. Low perceived control reported in a weekly diary was associated with more everyday memory problems among those with greater memory decline and low SOC strategy use (Est.=−0.28, SE=0.13, p=.036). These results suggest that the use of SOC strategies in the context of declining memory may help to buffer the negative effects of low perceived control on everyday memory. PMID:24597768

Everyday experiences of memory problems and control: the adaptive role of selective optimization with compensation in the context of memory decline.

PubMed

Hahn, Elizabeth A; Lachman, Margie E

2015-01-01

The present study examined the role of long-term working memory decline in the relationship between everyday experiences of memory problems and perceived control, and we also considered whether the use of accommodative strategies [selective optimization with compensation (SOC)] would be adaptive. The study included Boston-area participants (n = 103) from the Midlife in the United States study (MIDUS) who completed two working memory assessments over 10 years and weekly diaries following Time 2. In adjusted multi-level analyses, greater memory decline and lower general perceived control were associated with more everyday memory problems. Low perceived control reported in a weekly diary was associated with more everyday memory problems among those with greater memory decline and low SOC strategy use (Est. = -0.28, SE= 0.13, p = .036). These results suggest that the use of SOC strategies in the context of declining memory may help to buffer the negative effects of low perceived control on everyday memory.

Optimal design for robust control of uncertain flexible joint manipulators: a fuzzy dynamical system approach

NASA Astrophysics Data System (ADS)

Han, Jiang; Chen, Ye-Hwa; Zhao, Xiaomin; Dong, Fangfang

2018-04-01

A novel fuzzy dynamical system approach to the control design of flexible joint manipulators with mismatched uncertainty is proposed. Uncertainties of the system are assumed to lie within prescribed fuzzy sets. The desired system performance includes a deterministic phase and a fuzzy phase. First, by creatively implanting a fictitious control, a robust control scheme is constructed to render the system uniformly bounded and uniformly ultimately bounded. Both the manipulator modelling and control scheme are deterministic and not IF-THEN heuristic rules-based. Next, a fuzzy-based performance index is proposed. An optimal design problem for a control design parameter is formulated as a constrained optimisation problem. The global solution to this problem can be obtained from solving two quartic equations. The fuzzy dynamical system approach is systematic and is able to assure the deterministic performance as well as to minimise the fuzzy performance index.

The dynamics and optimal control of spinning spacecraft and movable telescoping appendages, part A. [two axis control with single offset boom

NASA Technical Reports Server (NTRS)

Bainum, P. M.; Sellappan, R.

1977-01-01

The problem of optimal control with a minimum time criterion as applied to a single boom system for achieving two axis control is discussed. The special case where the initial conditions are such that the system can be driven to the equilibrium state with only a single switching maneuver in the bang-bang optimal sequence is analyzed. The system responses are presented. Application of the linear regulator problem for the optimal control of the telescoping system is extended to consider the effects of measurement and plant noises. The noise uncertainties are included with an application of the estimator - Kalman filter problem. Different schemes for measuring the components of the angular velocity are considered. Analytical results are obtained for special cases, and numerical results are presented for the general case.

Human Factors of Remotely Piloted Aircraft

NASA Technical Reports Server (NTRS)

Hobbs, Alan Neville

2014-01-01

The civilian use of remotely piloted, or unmanned aircraft is expected to increase rapidly in the years ahead. Despite being referred to as unmanned some of the major challenges confronting this emerging sector relate to human factors. As unmanned aircraft systems (UAS) are introduced into civil airspace, a failure to adequately consider human factors could result in preventable accidents that may not only result in loss of life, but may also undermine public confidence in remotely piloted operations. Key issues include pilot situational awareness, collision avoidance in the absence of an out-the-window view, the effects of time delays in communication and control systems, control handovers, the challenges of very long duration flights, and the design of the control station. Problems have included poor physical layout of controls, non-intuitive automation interfaces, an over-reliance on text displays, and complicated sequences of menu selection to perform routine tasks. Some of the interface problems may have been prevented had an existing regulation or cockpit design principle been applied. In other cases, the design problems may indicate a lack of suitable guidance material.

A variable-gain output feedback control design approach

NASA Technical Reports Server (NTRS)

Haylo, Nesim

1989-01-01

A multi-model design technique to find a variable-gain control law defined over the whole operating range is proposed. The design is formulated as an optimal control problem which minimizes a cost function weighing the performance at many operating points. The solution is obtained by embedding into the Multi-Configuration Control (MCC) problem, a multi-model robust control design technique. In contrast to conventional gain scheduling which uses a curve fit of single model designs, the optimal variable-gain control law stabilizes the plant at every operating point included in the design. An iterative algorithm to compute the optimal control gains is presented. The methodology has been successfully applied to reconfigurable aircraft flight control and to nonlinear flight control systems.

Experiment and simulation for CSI: What are the missing links?

NASA Technical Reports Server (NTRS)

Belvin, W. Keith; Park, K. C.

1989-01-01

Viewgraphs on experiment and simulation for control structure interaction (CSI) are presented. Topics covered include: control structure interaction; typical control/structure interaction system; CSI problem classification; actuator/sensor models; modeling uncertainty; noise models; real-time computations; and discrete versus continuous.

The Relationship Between Motor Skills, Social Problems, and ADHD Symptomatology: Does It Vary According to Parent and Teacher Report?

PubMed

Goulardins, Juliana B; Rigoli, Daniela; Loh, Pek Ru; Kane, Robert; Licari, Melissa; Hands, Beth; Oliveira, Jorge A; Piek, Jan

2018-06-01

This study investigated the relationship between motor performance; attentional, hyperactive, and impulsive symptoms; and social problems. Correlations between parents' versus teachers' ratings of social problems and ADHD symptomatology were also examined. A total of 129 children aged 9 to 12 years were included. ADHD symptoms and social problems were identified based on Conners' Rating Scales-Revised: L, and the McCarron Assessment of Neuromuscular Development was used to assess motor skills. After controlling for ADHD symptomatology, motor skills remained a significant predictor of social problems in the teacher model but not in the parent model. After controlling for motor skills, inattentive (not hyperactive-impulsive) symptoms were a significant predictor of social problems in the parent model, whereas hyperactive-impulsive (not inattentive) symptoms were a significant predictor of social problems in the teacher model. The findings suggested that intervention strategies should consider the interaction between symptoms and environmental contexts.

Design tool for multiprocessor scheduling and evaluation of iterative dataflow algorithms

NASA Technical Reports Server (NTRS)

Jones, Robert L., III

1995-01-01

A graph-theoretic design process and software tool is defined for selecting a multiprocessing scheduling solution for a class of computational problems. The problems of interest are those that can be described with a dataflow graph and are intended to be executed repetitively on a set of identical processors. Typical applications include signal processing and control law problems. Graph-search algorithms and analysis techniques are introduced and shown to effectively determine performance bounds, scheduling constraints, and resource requirements. The software tool applies the design process to a given problem and includes performance optimization through the inclusion of additional precedence constraints among the schedulable tasks.

Aircraft Safety and Operating Problems. [conference

NASA Technical Reports Server (NTRS)

1976-01-01

Results of NASA research in the field of aircraft safety and operating problems are discussed. Topics include: (1) terminal area operations, (2) flight dynamics and control; (3) ground operations; (4) atmospheric environment; (5) structures and materials; (6) powerplants; (7) noise; and (8) human factors engineering.

Performance Analysis and the Generalization Problem.

ERIC Educational Resources Information Center

Wood, Scott; And Others

This document is intended to help school psychologists promote more effective generalization of school intervention programs for education students. Concepts (including transfer of training and response generalization) are reviewed. An approach is described which analyzes problem behavior according to its major controlling variables (skills or…

Precise computer controlled positioning of robot end effectors using force sensors

NASA Technical Reports Server (NTRS)

Shieh, L. S.; Mcinnis, B. C.; Wang, J. C.

1988-01-01

A thorough study of combined position/force control using sensory feedback for a one-dimensional manipulator model, which may count for the spacecraft docking problem or be extended to the multi-joint robot manipulator problem, was performed. The additional degree of freedom introduced by the compliant force sensor is included in the system dynamics in the design of precise position control. State feedback based on the pole placement method and with integral control is used to design the position controller. A simple constant gain force controller is used as an example to illustrate the dependence of the stability and steady-state accuracy of the overall position/force control upon the design of the inner position controller. Supportive simulation results are also provided.

Problem-solving deficits in Iranian people with borderline personality disorder.

PubMed

Akbari Dehaghi, Ashraf; Kaviani, Hossein; Tamanaeefar, Shima

2014-01-01

Interventions for people suffering from borderline personality disorder (BPD), such as dialectical behavior therapy, often include a problem-solving component. However, there is an absence of published studies examining the problem-solving abilities of this client group in Iran. The study compared inpatients and outpatients with BPD and a control group on problem-solving capabilities in an Iranian sample. It was hypothesized that patients with BPD would have more deficiencies in this area. Fifteen patients with BPD were compared to 15 healthy participants. Means-ends problem-solving task (MEPS) was used to measure problem-solving skills in both groups. BPD group reported less effective strategies in solving problems as opposed to the healthy group. Compared to the control group, participants with BPD provided empirical support for the use of problem-solving interventions with people suffering from BPD. The findings supported the idea that a problem-solving intervention can be efficiently applied either as a stand-alone therapy or in conjunction with other available psychotherapies to treat people with BPD.

Sensitivity, optimal scaling and minimum roundoff errors in flexible structure models

NASA Technical Reports Server (NTRS)

Skelton, Robert E.

1987-01-01

Traditional modeling notions presume the existence of a truth model that relates the input to the output, without advanced knowledge of the input. This has led to the evolution of education and research approaches (including the available control and robustness theories) that treat the modeling and control design as separate problems. The paper explores the subtleties of this presumption that the modeling and control problems are separable. A detailed study of the nature of modeling errors is useful to gain insight into the limitations of traditional control and identification points of view. Modeling errors need not be small but simply appropriate for control design. Furthermore, the modeling and control design processes are inevitably iterative in nature.

Changes in Problem-Solving Capacity and Association With Spontaneous Brain Activity After a Single Electroconvulsive Treatment in Major Depressive Disorder.

PubMed

Du, Lian; Qiu, Haitang; Liu, Haixia; Zhao, Wenjing; Tang, Yong; Fu, Yixiao; Li, Xirong; Qiu, Tian; Hu, Hua; Meng, Huaqing; Luo, Qinghua

2016-03-01

Modified electroconvulsive therapy (MECT) has been regarded as the most effective antidepressant therapy, despite its cognitive side effects. However, how MECT influences problem-solving capacity in major depressive disorder (MDD), as well as its underlying neurobiological mechanisms, remains unclear. The present study aimed to assess alterations in problem-solving capacity after MECT and to explore spontaneous brain activity using amplitudes of low-frequency fluctuations (ALFF)/fractional ALFF. Thirteen first-episode, treatment-naive MDD patients treated by MECT were recruited. We collected resting-state functional magnetic resonance imaging, and we evaluated their Modified Card Sorting Test performance before and after single-session MECT. Another 11 MDD patients without MECT were also recruited and interviewed with Modified Card Sorting Test twice as a control group. After a single MECT, MDD patients showed significantly decreased ALFF in the right cerebellar posterior lobe. Compared to the control group, perseverative errors significantly decreased after MECT, controlling for practice effects. Some cognitive functional changes significantly correlated to changed ALFF in several brain regions, including Brodmann areas BA9, BA19, BA 21, and BA48, right thalamus, left cerebellum, and right postcentral gyrus. The MECT could improve problem-solving capacity, even after controlling for practice effects, and it could induce changes in spontaneous brain activity. These changes in cognitive functioning might result from changes in the cerebral functions of some regions, including frontal cortex, a key region for problem-solving capacity.

Community Violence Exposure and Conduct Problems in Children and Adolescents with Conduct Disorder and Healthy Controls.

PubMed

Kersten, Linda; Vriends, Noortje; Steppan, Martin; Raschle, Nora M; Praetzlich, Martin; Oldenhof, Helena; Vermeiren, Robert; Jansen, Lucres; Ackermann, Katharina; Bernhard, Anka; Martinelli, Anne; Gonzalez-Madruga, Karen; Puzzo, Ignazio; Wells, Amy; Rogers, Jack C; Clanton, Roberta; Baker, Rosalind H; Grisley, Liam; Baumann, Sarah; Gundlach, Malou; Kohls, Gregor; Gonzalez-Torres, Miguel A; Sesma-Pardo, Eva; Dochnal, Roberta; Lazaratou, Helen; Kalogerakis, Zacharias; Bigorra Gualba, Aitana; Smaragdi, Areti; Siklósi, Réka; Dikeos, Dimitris; Hervás, Amaia; Fernández-Rivas, Aranzazu; De Brito, Stephane A; Konrad, Kerstin; Herpertz-Dahlmann, Beate; Fairchild, Graeme; Freitag, Christine M; Popma, Arne; Kieser, Meinhard; Stadler, Christina

2017-01-01

Exposure to community violence through witnessing or being directly victimized has been associated with conduct problems in a range of studies. However, the relationship between community violence exposure (CVE) and conduct problems has never been studied separately in healthy individuals and individuals with conduct disorder (CD). Therefore, it is not clear whether the association between CVE and conduct problems is due to confounding factors, because those with high conduct problems also tend to live in more violent neighborhoods, i.e., an ecological fallacy. Hence, the aim of the present study was: (1) to investigate whether the association between recent CVE and current conduct problems holds true for healthy controls as well as adolescents with a diagnosis of CD; (2) to examine whether the association is stable in both groups when including effects of aggression subtypes (proactive/reactive aggression), age, gender, site and socioeconomic status (SES); and (3) to test whether proactive or reactive aggression mediate the link between CVE and conduct problems. Data from 1178 children and adolescents (62% female; 44% CD) aged between 9 years and 18 years from seven European countries were analyzed. Conduct problems were assessed using the Kiddie-Schedule of Affective Disorders and Schizophrenia diagnostic interview. Information about CVE and aggression subtypes was obtained using self-report questionnaires (Social and Health Assessment and Reactive-Proactive aggression Questionnaire (RPQ), respectively). The association between witnessing community violence and conduct problems was significant in both groups (adolescents with CD and healthy controls). The association was also stable after examining the mediating effects of aggression subtypes while including moderating effects of age, gender and SES and controlling for effects of site in both groups. There were no clear differences between the groups in the strength of the association between witnessing violence and conduct problems. However, we found evidence for a ceiling effect, i.e., individuals with very high levels of conduct problems could not show a further increase if exposed to CVE and vice versa. Results indicate that there was no evidence for an ecological fallacy being the primary cause of the association, i.e., CVE must be considered a valid risk factor in the etiology of CD.

Offspring ADHD as a risk factor for parental marital problems: controls for genetic and environmental confounds.

PubMed

Schermerhorn, Alice C; D'Onofrio, Brian M; Slutske, Wendy S; Emery, Robert E; Turkheimer, Eric; Harden, K Paige; Heath, Andrew C; Martin, Nicholas G

2012-12-01

Previous studies have found that child attention-deficit/hyperactivity disorder (ADHD) is associated with more parental marital problems. However, the reasons for this association are unclear. The association might be due to genetic or environmental confounds that contribute to both marital problems and ADHD. Data were drawn from the Australian Twin Registry, including 1,296 individual twins, their spouses, and offspring. We studied adult twins who were discordant for offspring ADHD.Using a discordant twin pairs design, we examined the extent to which genetic and environmental confounds,as well as measured parental and offspring characteristics, explain the ADHD-marital problems association. Offspring ADHD predicted parental divorce and marital conflict. The associations were also robust when comparing differentially exposed identical twins to control for unmeasured genetic and environmental factors, when controlling for measured maternal and paternal psychopathology,when restricting the sample based on timing of parental divorce and ADHD onset, and when controlling for other forms of offspring psychopathology. Each of these controls rules out alternative explanations for the association. The results of the current study converge with those of prior research in suggesting that factors directly associated with offspring ADHD increase parental marital problems.

Optimal Routing and Control of Multiple Agents Moving in a Transportation Network and Subject to an Arrival Schedule and Separation Constraints

NASA Technical Reports Server (NTRS)

Sadovsky, A. V.; Davis, D.; Isaacson, D. R.

2012-01-01

We address the problem of navigating a set of moving agents, e.g. automated guided vehicles, through a transportation network so as to bring each agent to its destination at a specified time. Each pair of agents is required to be separated by a minimal distance, generally agent-dependent, at all times. The speed range, initial position, required destination, and required time of arrival at destination for each agent are assumed provided. The movement of each agent is governed by a controlled differential equation (state equation). The problem consists in choosing for each agent a path and a control strategy so as to meet the constraints and reach the destination at the required time. This problem arises in various fields of transportation, including Air Traffic Management and train coordination, and in robotics. The main contribution of the paper is a model that allows to recast this problem as a decoupled collection of problems in classical optimal control and is easily generalized to the case when inertia cannot be neglected. Some qualitative insight into solution behavior is obtained using the Pontryagin Maximum Principle. Sample numerical solutions are computed using a numerical optimal control solver.

Offspring ADHD as a Risk Factor for Parental Marital Problems: Controls for Genetic and Environmental Confounds

PubMed Central

Schermerhorn, Alice C.; D’Onofrio, Brian M.; Slutske, Wendy S.; Emery, Robert E.; Turkheimer, Eric; Harden, K. Paige; Heath, Andrew C.; Martin, Nicholas G.

2013-01-01

Background Previous studies have found that child attention-deficit/hyperactivity disorder (ADHD) is associated with more parental marital problems. The reasons for this association are unclear, however. The association might be due to genetic or environmental confounds that contribute to both marital problems and ADHD. Method Data were drawn from the Australian Twin Registry, including 1296 individual twins, their spouses, and offspring. We studied adult twins who were discordant for offspring ADHD. Using a discordant twin pairs design, we examined the extent to which genetic and environmental confounds, as well as measured parental and offspring characteristics, explain the ADHD-marital problems association. Results Offspring ADHD predicted parental divorce and marital conflict. The associations were also robust when comparing differentially exposed identical twins to control for unmeasured genetic and environmental factors, when controlling for measured maternal and paternal psychopathology, when restricting the sample based on timing of parental divorce and ADHD onset, and when controlling for other forms of offspring psychopathology. Each of these controls rules out alternative explanations for the association. Conclusion The results of the current study converge with those of prior research in suggesting that factors directly associated with offspring ADHD increase parental marital problems. PMID:22958575

Coping and social problem solving correlates of asthma control and quality of life.

PubMed

McCormick, Sean P; Nezu, Christine M; Nezu, Arthur M; Sherman, Michael; Davey, Adam; Collins, Bradley N

2014-02-01

In a sample of adults with asthma receiving care and medication in an outpatient pulmonary clinic, this study tested for statistical associations between social problem-solving styles, asthma control, and asthma-related quality of life. These variables were measured cross sectionally as a first step toward more systematic application of social problem-solving frameworks in asthma self-management training. Recruitment occurred during pulmonology clinic service hours. Forty-four adults with physician-confirmed diagnosis of asthma provided data including age, gender, height, weight, race, income, and comorbid conditions. The Asthma Control Questionnaire, the Mini Asthma Quality of Life Questionnaire (Short Form), and peak expiratory force measures offered multiple views of asthma health at the time of the study. Maladaptive coping (impulsive and careless problem-solving styles) based on transactional stress models of health were assessed with the Social Problem-Solving Inventory-Revised: Short Form. Controlling for variance associated with gender, age, and income, individuals reporting higher impulsive-careless scores exhibited significantly lower scores on asthma control (β = 0.70, p = 0.001, confidence interval (CI) [0.37-1.04]) and lower asthma-related quality of life (β = 0.79, p = 0.017, CI [0.15-1.42]). These findings suggest that specific maladaptive problem-solving styles may uniquely contribute to asthma health burdens. Because problem-solving coping strategies are both measureable and teachable, behavioral interventions aimed at facilitating adaptive coping and problem solving could positively affect patient's asthma management and quality of life.

Behavioral control in at-risk toddlers: the influence of the family check-up.

PubMed

Shelleby, Elizabeth C; Shaw, Daniel S; Cheong, Jeewon; Chang, Hyein; Gardner, Frances; Dishion, Thomas J; Wilson, Melvin N

2012-01-01

This study examines the role of one component of emotion regulation, behavioral control, in the growth of children's early behavior problems by examining whether increases in parental positive behavior support brought about by a family-centered intervention were associated with greater child behavioral control, and whether greater behavioral control at age 3 mediated the association between improvements in aspects of positive behavior support from ages 2 to 3 and decreases in growth of behavior problems from ages 2 to 4. The sample included 713 at-risk children (50% female) and their primary caregivers (50% European American, 28% African American, 13% biracial, 9% other) who were randomly assigned to the intervention or control group. Children had a mean age of 29.91 months at the initial assessment. Data were collected through home visits at child ages 2 to 4, which involved questionnaires for primary caregivers and structured and unstructured play activities for children with primary and alternative caregivers and siblings. Results indicated that the intervention improved parental positive behavior support and reduced growth of child behavior problems. One dimension of positive behavior support, proactive parenting, was modestly associated with behavioral control at age 3, which in turn was significantly associated with growth in behavior problems from ages 2 to 4, with greater behavioral control related to lower levels of growth in behavior problems. Results provide support for the notion that proactive parenting is an important factor in the development of children's behavioral control and that behavioral control plays an important role in the growth of behavior problems.

The Lived Experience of Iranian Women Confronting Breast Cancer Diagnosis.

PubMed

Mehrabi, Esmat; Hajian, Sepideh; Simbar, Masoomeh; Hoshyari, Mohammad; Zayeri, Farid

2016-03-01

The populations who survive from breast cancer are growing; nevertheless, they mostly encounter with many cancer related problems in their life, especially after early diagnosis and have to deal with these problems. Except for the disease entity, several socio-cultural factors may affect confronting this challenge among patients and the way they deal with. Present study was carried out to prepare clear understanding of Iranian women's lived experiences confronting breast cancer diagnosis and coping ways they applied to deal with it. This study was carried out by using qualitative phenomenological design. Data gathering was done through purposive sampling using semi-structured, in-depth interviews with 18 women who survived from breast cancer. The transcribed interviews were analyzed using Van Manen's thematic analysis approach. Two main themes were emerged from the interviews including "emotional turbulence" and "threat control". The first, comprised three sub themes including uncertainty, perceived worries, and living with fears. The second included risk control, recurrence control, immediate seeking help, seeking support and resource to spirituality. Emotional response was the immediate reflection to cancer diagnosis. However, during post-treatment period a variety of emotions were not uncommon findings, patients' perceptions have been changing along the time and problem-focused coping strategies have replaced. Although women may experience a degree of improvement and adjustment with illness, the emotional problems are not necessarily resolved, they may continue and gradually engender positive outcomes.

Coordinative Voltage Control Strategy with Multiple Resources for Distribution Systems of High PV Penetration: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Xiangqi; Zhang, Yingchen

This paper presents an optimal voltage control methodology with coordination among different voltage-regulating resources, including controllable loads, distributed energy resources such as energy storage and photovoltaics (PV), and utility voltage-regulating devices such as voltage regulators and capacitors. The proposed methodology could effectively tackle the overvoltage and voltage regulation device distortion problems brought by high penetrations of PV to improve grid operation reliability. A voltage-load sensitivity matrix and voltage-regulator sensitivity matrix are used to deploy the resources along the feeder to achieve the control objectives. Mixed-integer nonlinear programming is used to solve the formulated optimization control problem. The methodology has beenmore » tested on the IEEE 123-feeder test system, and the results demonstrate that the proposed approach could actively tackle the voltage problem brought about by high penetrations of PV and improve the reliability of distribution system operation.« less

Clean the Air and Breathe Easier.

ERIC Educational Resources Information Center

Guevin, John

1997-01-01

Failure to prevent indoor air quality problems or act promptly can result in increased chances for long- or short-term health problems for staff and students, reduced productivity, faster plant deterioration, and strained school-community relations. Basic pollution control measures include source management, local exhausts, ventilation, exposure…

The Application of Science and Technology to Public Programs.

ERIC Educational Resources Information Center

Feller, Irwin

Conference papers, recommendations, and discussion are compiled, focusing on the complex of problems associated with rapidly expanding urbanization and consequent rural dislocation. Topics exploring the problems included: air and water pollution; program planning and management; solid waste disposal; transportation; housing; crime control; health…

Sex Differences and Self-Reported Attention Problems During Baseline Concussion Testing.

PubMed

Brooks, Brian L; Iverson, Grant L; Atkins, Joseph E; Zafonte, Ross; Berkner, Paul D

2016-01-01

Amateur athletic programs often use computerized cognitive testing as part of their concussion management programs. There is evidence that athletes with preexisting attention problems will have worse cognitive performance and more symptoms at baseline testing. The purpose of this study was to examine whether attention problems affect assessments differently for male and female athletes. Participants were drawn from a database that included 6,840 adolescents from Maine who completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) at baseline (primary outcome measure). The final sample included 249 boys and 100 girls with self-reported attention problems. Each participant was individually matched for sex, age, number of past concussions, and sport to a control participant (249 boys, 100 girls). Boys with attention problems had worse reaction time than boys without attention problems. Girls with attention problems had worse visual-motor speed than girls without attention problems. Boys with attention problems reported more total symptoms, including more cognitive-sensory and sleep-arousal symptoms, compared with boys without attention problems. Girls with attention problems reported more cognitive-sensory, sleep-arousal, and affective symptoms than girls without attention problems. When considering the assessment, management, and outcome from concussions in adolescent athletes, it is important to consider both sex and preinjury attention problems regarding cognitive test results and symptom reporting.

Flight Studies of Problems Pertinent to High-Speed Operation of Jet Transports

NASA Technical Reports Server (NTRS)

Butchart, Stanley P.; Fischel, Jack; Tremant, Robert A.; Robinson, Glenn H.

1959-01-01

A flight investigation was made to assess the potential operational problems of jet transports in the transonic cruise range. In this study a large multiengine jet airplane having geometric characteristics fairly representative of the jet transport was used; however, in order to ensure general applicability of the results, the aerodynamic characteristics of the test airplane were varied to simulate a variety of jet- transport airplanes. Some of the specific areas investigated include: (1) an overall evaluation of longitudinal stability and control characteristics at transonic speeds, with an assessment of pitch-up characteristics, (2) the effect of buffeting on airplane operational speeds and maneuvering, (3) the desirable lateral-directional damping characteristics, (4) the desirable lateral-control characteristics, (5) an assessment of over-speed and speed-spread requirements, including the upset maneuver, and (6) an assessment of techniques and airplane characteristics for rapid descent and slow-down. The results presented include pilots' evaluation of the various problem areas and specific recommendations for possible improvement of jet-transport operations in the cruising speed range.

Childhood Reports of Food Neglect and Impulse Control Problems and Violence in Adulthood

PubMed Central

Vaughn, Michael G.; Salas-Wright, Christopher P.; Naeger, Sandra; Huang, Jin; Piquero, Alex R.

2016-01-01

Food insecurity and hunger during childhood are associated with an array of developmental problems in multiple domains, including impulse control problems and violence. Unfortunately, extant research is based primarily on small convenience samples and an epidemiological assessment of the hunger-violence link is lacking. The current study employed data from Wave 1 (2001–2002) and Wave 2 (2004–2005) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). The NESARC is a nationally representative sample of non-institutionalized U.S. residents aged 18 years and older. Participants who experienced frequent hunger during childhood had significantly greater impulsivity, worse self-control, and greater involvement in several forms of interpersonal violence. These effects were stronger among whites, Hispanics, and males. The findings support general theoretical models implicating impulse control problems as a key correlate of crime and violence and add another facet to the importance of ameliorating food neglect in the United States. PMID:27043598

The indoor air we breathe.

PubMed Central

Oliver, L C; Shackleton, B W

1998-01-01

Increasingly recognized as a potential public health problem since the outbreak of Legionnaire's disease in Philadelphia in 1976, polluted indoor air has been associated with health problems that include asthma, sick building syndrome, multiple chemical sensitivity, and hypersensitivity pneumonitis. Symptoms are often nonspecific and include headache, eye and throat irritation, chest tightness and shortness of breath, and fatigue. Air-borne contaminants include commonly used chemicals, vehicular exhaust, microbial organisms, fibrous glass particles, and dust. Identified causes include defective building design and construction, aging of buildings and their ventilation systems, poor climate control, inattention to building maintenance. A major contributory factor is the explosion in the use of chemicals in building construction and furnishing materials over the past four decades. Organizational issues and psychological variables often contribute to the problem and hinder its resolution. This article describes the health problems related to poor indoor air quality and offers solutions. Images p398-a p399-a PMID:9769764

Research into the development of a knowledge acquisition taxonomy

NASA Technical Reports Server (NTRS)

Fink, Pamela K.

1991-01-01

Monthly progress reports for September 1990 to January 1991 are given. Topics that are briefly covered include problem solving and learning taxonomies, knowledge acquisition techniques, software design, air traffic control, and space shuttle flight control.

Optimal control design of turbo spin‐echo sequences with applications to parallel‐transmit systems

PubMed Central

Hoogduin, Hans; Hajnal, Joseph V.; van den Berg, Cornelis A. T.; Luijten, Peter R.; Malik, Shaihan J.

2016-01-01

Purpose The design of turbo spin‐echo sequences is modeled as a dynamic optimization problem which includes the case of inhomogeneous transmit radiofrequency fields. This problem is efficiently solved by optimal control techniques making it possible to design patient‐specific sequences online. Theory and Methods The extended phase graph formalism is employed to model the signal evolution. The design problem is cast as an optimal control problem and an efficient numerical procedure for its solution is given. The numerical and experimental tests address standard multiecho sequences and pTx configurations. Results Standard, analytically derived flip angle trains are recovered by the numerical optimal control approach. New sequences are designed where constraints on radiofrequency total and peak power are included. In the case of parallel transmit application, the method is able to calculate the optimal echo train for two‐dimensional and three‐dimensional turbo spin echo sequences in the order of 10 s with a single central processing unit (CPU) implementation. The image contrast is maintained through the whole field of view despite inhomogeneities of the radiofrequency fields. Conclusion The optimal control design sheds new light on the sequence design process and makes it possible to design sequences in an online, patient‐specific fashion. Magn Reson Med 77:361–373, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine PMID:26800383

Agricultural Science Protects Our Environment.

ERIC Educational Resources Information Center

1967

Included are a 49 frame filmstrip and a script for narrating a presentation. The presentation is aimed at the secondary school level with an emphasis on how agricultural scientists investigate problems in farmland erosion, stream pollution, road building erosion problems, air pollution, farm pollution, pesticides, and insect control by biological…

Alcohol Policy Considerations for Indian Reservations and Bordertown Communities.

ERIC Educational Resources Information Center

May, Philip A.

1992-01-01

Alcohol abuse and alcoholism are the leading health problems among American Indian communities. Public policy options that address these problems include controlling the supply of alcoholic beverages; shaping drinking practices directly; or reducing physical and social environmental risks. Discusses alcohol-related death rates and community…

APTI Course 427, Combustion Evaluation. Student Workbook.

ERIC Educational Resources Information Center

Beard, J. Taylor; And Others

Presented are exercises intended to supplement course work in air pollution control, specifically as they relate to combustion. Chapters offered in this workbook include: (1) Combustion Calculations, (2) Combustion System Design Problems, (3) Emission Calculations I, (4) Emission Calculations II, (5) Afterburner Design Problems, and (6) Cumbustion…

Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

NASA Astrophysics Data System (ADS)

Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

2017-02-01

The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

Pseudo-spectral control of a novel oscillating surge wave energy converter in regular waves for power optimization including load reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tom, Nathan M.; Yu, Yi -Hsiang; Wright, Alan D.

The aim of this study is to describe a procedure to maximize the power-to-load ratio of a novel wave energy converter (WEC) that combines an oscillating surge wave energy converter with variable structural components. The control of the power-take-off torque will be on a wave-to-wave timescale, whereas the structure will be controlled statically such that the geometry remains the same throughout the wave period. Linear hydrodynamic theory is used to calculate the upper and lower bounds for the time-averaged absorbed power and surge foundation loads while assuming that the WEC motion remains sinusoidal. Previous work using pseudo-spectral techniques to solvemore » the optimal control problem focused solely on maximizing absorbed energy. This work extends the optimal control problem to include a measure of the surge foundation force in the optimization. The objective function includes two competing terms that force the optimizer to maximize power capture while minimizing structural loads. A penalty weight was included with the surge foundation force that allows control of the optimizer performance based on whether emphasis should be placed on power absorption or load shedding. Results from pseudo-spectral optimal control indicate that a unit reduction in time-averaged power can be accompanied by a greater reduction in surge-foundation force.« less

Pseudo-spectral control of a novel oscillating surge wave energy converter in regular waves for power optimization including load reduction

DOE PAGES

Tom, Nathan M.; Yu, Yi -Hsiang; Wright, Alan D.; ...

2017-04-18

The aim of this study is to describe a procedure to maximize the power-to-load ratio of a novel wave energy converter (WEC) that combines an oscillating surge wave energy converter with variable structural components. The control of the power-take-off torque will be on a wave-to-wave timescale, whereas the structure will be controlled statically such that the geometry remains the same throughout the wave period. Linear hydrodynamic theory is used to calculate the upper and lower bounds for the time-averaged absorbed power and surge foundation loads while assuming that the WEC motion remains sinusoidal. Previous work using pseudo-spectral techniques to solvemore » the optimal control problem focused solely on maximizing absorbed energy. This work extends the optimal control problem to include a measure of the surge foundation force in the optimization. The objective function includes two competing terms that force the optimizer to maximize power capture while minimizing structural loads. A penalty weight was included with the surge foundation force that allows control of the optimizer performance based on whether emphasis should be placed on power absorption or load shedding. Results from pseudo-spectral optimal control indicate that a unit reduction in time-averaged power can be accompanied by a greater reduction in surge-foundation force.« less

Singular Optimal Controls of Rocket Motion (Survey)

NASA Astrophysics Data System (ADS)

Kiforenko, B. N.

2017-05-01

Survey of modern state and discussion of problems of the perfection of methods of investigation of variational problems with a focus on mechanics of space flight are presented. The main attention is paid to the enhancement of the methods of solving of variational problems of rocket motion in the gravitational fields, including rocket motion in the atmosphere. These problems are directly connected with the permanently actual problem of the practical astronautics to increase the payload that is orbited by the carrier rockets in the circumplanetary orbits. An analysis of modern approaches to solving the problems of control of rockets and spacecraft motion on the trajectories with singular arcs that are optimal for the motion of the variable mass body in the medium with resistance is given. The presented results for some maneuvers can serve as an information source for decision making on designing promising rocket and space technology

Child-Level Predictors of Responsiveness to Evidence-Based Mathematics Intervention.

PubMed

Powell, Sarah R; Cirino, Paul T; Malone, Amelia S

2017-07-01

We identified child-level predictors of responsiveness to 2 types of mathematics (calculation and word-problem) intervention among 2nd-grade children with mathematics difficulty. Participants were 250 children in 107 classrooms in 23 schools pretested on mathematics and general cognitive measures and posttested on mathematics measures. We assigned classrooms randomly assigned to calculation intervention, word-problem intervention, or business-as-usual control. Intervention lasted 17 weeks. Path analyses indicated that scores on working memory and language comprehension assessments moderated responsiveness to calculation intervention. No moderators were identified for responsiveness to word-problem intervention. Across both intervention groups and the control group, attentive behavior predicted both outcomes. Initial calculation skill predicted the calculation outcome, and initial language comprehension predicted word-problem outcomes. These results indicate that screening for calculation intervention should include a focus on working memory, language comprehension, attentive behavior, and calculations. Screening for word-problem intervention should focus on attentive behavior and word problems.

Commercial jet fuel quality control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strauss, K.H.

1995-05-01

The paper discusses the purpose of jet fuel quality control between the refinery and the aircraft. It describes fixed equipment, including various types of filters, and the usefulness and limitations of this equipment. Test equipment is reviewed as are various surveillance procedures. These include the Air Transport Association specification ATA 103, the FAA Advisory Circular 150/5230-4, the International Air Transport Association Guidance Material for Fuel Quality Control and Fuelling Service and the Guidelines for Quality Control at Jointly Operated Fuel Systems. Some past and current quality control problems are briefly mentioned.

Distributed formation control of nonholonomic autonomous vehicle via RBF neural network

NASA Astrophysics Data System (ADS)

Yang, Shichun; Cao, Yaoguang; Peng, Zhaoxia; Wen, Guoguang; Guo, Konghui

2017-03-01

In this paper, RBF neural network consensus-based distributed control scheme is proposed for nonholonomic autonomous vehicles in a pre-defined formation along the specified reference trajectory. A variable transformation is first designed to convert the formation control problem into a state consensus problem. Then, the complete dynamics of the vehicles including inertia, Coriolis, friction model and unmodeled bounded disturbances are considered, which lead to the formation unstable when the distributed kinematic controllers are proposed based on the kinematics. RBF neural network torque controllers are derived to compensate for them. Some sufficient conditions are derived to accomplish the asymptotically stability of the systems based on algebraic graph theory, matrix theory, and Lyapunov theory. Finally, simulation examples illustrate the effectiveness of the proposed controllers.

Public Health Control Measures in Response to Global Pandemics and Drug Resistance.

PubMed

Price, Polly J

2015-01-01

These teaching materials provide problem-based exercises exploring the specific powers of governments to implement control measures in response to communicable disease. Topics include global pandemic disease and, in the United States, legal issues in tuberculosis control. © 2015 American Society of Law, Medicine & Ethics, Inc.

Can I Take the Car? Relations among Parenting Practices and Adolescent Problem-Driving Practices.

ERIC Educational Resources Information Center

Hartos, Jessica L.; Eitel, Patricia; Haynie, Denise L.; Simons-Morton, Bruce G.

2000-01-01

Examined relationships among parenting practices and problem-driving practices among licensed adolescents with less than 2 years of driving experience. Found that factors significantly related to risky driving behaviors, traffic violations, and motor vehicle crashes included lower levels of parental monitoring and control, lenient parental…

Conduct Problems, IQ, and Household Chaos: A Longitudinal Multi-Informant Study

ERIC Educational Resources Information Center

Deater-Deckard, Kirby; Mullineaux, Paula Y.; Beekman, Charles; Petrill, Stephen A.; Schatschneider, Chris; Thompson, Lee A.

2009-01-01

Background: We tested the hypothesis that household chaos would be associated with lower child IQ and more child conduct problems concurrently and longitudinally over two years while controlling for housing conditions, parent education/IQ, literacy environment, parental warmth/negativity, and stressful events. Methods: The sample included 302…

Problem-Solving Therapy for Depression in Adults: A Systematic Review

ERIC Educational Resources Information Center

Gellis, Zvi D.; Kenaley, Bonnie

2008-01-01

Objectives: This article presents a systematic review of the evidence on problem-solving therapy (PST) for depressive disorders in noninstitutionalized adults. Method: Intervention studies using randomized controlled designs are included and methodological quality is assessed using a standard set of criteria from the Cochrane Collaborative Review…

Eliminating Problem Behaviors with Positive Controls.

ERIC Educational Resources Information Center

Stoi, Margaret

A teacher describes her efforts to deal with an 11-year-old severely emotionally impaired girl in a classroom with other acting out, aggressive students. The girl's behavior problems included breaking, tearing, spitting, swearing, running, and sexual aggression. A positive reinforcedment system was found to be primarily responsible for success in…

Air Pollution.

ERIC Educational Resources Information Center

Gilpin, Alan

A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

Water Pollution Control Industry

ERIC Educational Resources Information Center

Environmental Science and Technology, 1974

1974-01-01

A special report on the state of the water pollution control industry reveals that due to forthcoming federal requirements, sales and the backlogs should increase; problems may ensue because of shortages of materials and inflation. Included are reports from various individual companies. (MLB)

A review of feral cat control.

PubMed

Robertson, Sheilah A

2008-08-01

Animal overpopulation including feral cats is an important global problem. There are many stakeholders involved in the feral cat debate over 'what to do about the problem', including those who consider them a nuisance, the public at risk from zoonotic disease, people who are concerned about the welfare of feral cats, those concerned with wildlife impacts, and the cats themselves. How best to control this population is controversial and has ranged from culling, relocation, and more recently 'trap neuter return' (TNR) methods. Data support the success of TNR in reducing cat populations, but to have a large impact it will have to be adopted on a far greater scale than it is currently practised. Non-surgical contraception is a realistic future goal. Because the feral cat problem was created by humans, concerted educational efforts on responsible pet ownership and the intrinsic value of animals is an integral part of a solution.

Ongoing Progress in Spacecraft Controls

NASA Technical Reports Server (NTRS)

Ghosh, Dave (Editor)

1992-01-01

This publication is a collection of papers presented at the Mars Mission Research Center workshop on Ongoing Progress in Spacecraft Controls. The technical program addressed additional Mars mission control problems that currently exist in robotic missions in addition to human missions. Topics include control systems design in the presence of large time delays, fuel-optimal propulsive control, and adaptive control to handle a variety of unknown conditions.

Active vibration mitigation of distributed parameter, smart-type structures using Pseudo-Feedback Optimal Control (PFOC)

NASA Technical Reports Server (NTRS)

Patten, W. N.; Robertshaw, H. H.; Pierpont, D.; Wynn, R. H.

1989-01-01

A new, near-optimal feedback control technique is introduced that is shown to provide excellent vibration attenuation for those distributed parameter systems that are often encountered in the areas of aeroservoelasticity and large space systems. The technique relies on a novel solution methodology for the classical optimal control problem. Specifically, the quadratic regulator control problem for a flexible vibrating structure is first cast in a weak functional form that admits an approximate solution. The necessary conditions (first-order) are then solved via a time finite-element method. The procedure produces a low dimensional, algebraic parameterization of the optimal control problem that provides a rigorous basis for a discrete controller with a first-order like hold output. Simulation has shown that the algorithm can successfully control a wide variety of plant forms including multi-input/multi-output systems and systems exhibiting significant nonlinearities. In order to firmly establish the efficacy of the algorithm, a laboratory control experiment was implemented to provide planar (bending) vibration attenuation of a highly flexible beam (with a first clamped-free mode of approximately 0.5 Hz).

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

Gisser, D. G.; Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Yerazunis, S. Y.

1975-01-01

Problems related to an unmanned exploration of the planet Mars by means of an autonomous roving planetary vehicle are investigated. These problems include: design, construction and evaluation of the vehicle itself and its control and operating systems. More specifically, vehicle configuration, dynamics, control, propulsion, hazard detection systems, terrain sensing and modelling, obstacle detection concepts, path selection, decision-making systems, and chemical analyses of samples are studied. Emphasis is placed on development of a vehicle capable of gathering specimens and data for an Augmented Viking Mission or to provide the basis for a Sample Return Mission.

A longitudinal comparative study of the physical and mental health problems of affected residents of the firework disaster Enschede, The Netherlands.

PubMed

Grievink, L; van der Velden, P G; Stellato, R K; Dusseldorp, A; Gersons, B P R; Kleber, R J; Lebret, E

2007-05-01

After the firework disaster in Enschede, The Netherlands, on 13 May 2000, a longitudinal health study was carried out. Study questions were: (1) did the health status change over this period; and (2) how is the health status 18 months after the disaster compared with controls? A longitudinal comparative study with two surveys at 3 weeks and 18 months after the disaster. A control group for the affected residents was included in the second survey. Respondents filled in a set of validated questionnaires measuring their physical and mental health problems. The prevalence of physical and emotional role limitations, severe sleeping problems, feelings of depression and anxiety, as well as intrusion and avoidance decreased from 3 weeks to 18 months after the disaster for the affected residents. Independent of background characteristics and other life events, residents had 1.5 to three times more health problems than the control group; for example, physical role limitations (odds ratio [OR]=1.5, 95% confidence interval [CI] 1.2-2.0) and anxiety (OR=3.1, 95% CI 2.4-4.2). Although health problems decreased compared with 3 weeks after the disaster, 18 months after the disaster, the affected residents had more health problems than the people from the control group.

Unplanned Drinking and Alcohol-Related Problems: A Preliminary Test of the Model of Unplanned Drinking Behavior

PubMed Central

Pearson, Matthew R.; Henson, James M.

2013-01-01

Much research links impulsivity with alcohol use and problems. In two studies, unplanned (or impulsive) drinking is assessed directly to determine whether it has direct effects on alcohol use and alcohol-related problems. In study 1, we examined whether unplanned drinking serves as a proximal mediator of the effects of impulsivity-like traits on alcohol-related outcomes. With a sample of 211 college student drinkers, we found that the Unplanned Drinking Scale was significantly related to alcohol use, and perhaps more importantly, had a direct effect on alcohol-related problems even after controlling for frequency and quantity of alcohol use. Further, unplanned drinking partially mediated the effects of negative urgency on alcohol-related problems. In study 2, we examined whether unplanned drinking accounts for unique variance in alcohol-related outcomes when controlling for use of protective behavioral strategies. With a sample of 170 college students, we replicated the findings of Study 1 in that the Unplanned Drinking Scale had a significant direct effect on alcohol-related problems even after controlling for alcohol use; further, this effect was maintained when controlling for use of protective behavioral strategies. Limitations include the modest sample sizes and the cross-sectional design. Future directions for testing the Model of Unplanned Drinking Behavior are proposed. PMID:23276312

Multi-Objective Trajectory Optimization of a Hypersonic Reconnaissance Vehicle with Temperature Constraints

NASA Astrophysics Data System (ADS)

Masternak, Tadeusz J.

This research determines temperature-constrained optimal trajectories for a scramjet-based hypersonic reconnaissance vehicle by developing an optimal control formulation and solving it using a variable order Gauss-Radau quadrature collocation method with a Non-Linear Programming (NLP) solver. The vehicle is assumed to be an air-breathing reconnaissance aircraft that has specified takeoff/landing locations, airborne refueling constraints, specified no-fly zones, and specified targets for sensor data collections. A three degree of freedom scramjet aircraft model is adapted from previous work and includes flight dynamics, aerodynamics, and thermal constraints. Vehicle control is accomplished by controlling angle of attack, roll angle, and propellant mass flow rate. This model is incorporated into an optimal control formulation that includes constraints on both the vehicle and mission parameters, such as avoidance of no-fly zones and coverage of high-value targets. To solve the optimal control formulation, a MATLAB-based package called General Pseudospectral Optimal Control Software (GPOPS-II) is used, which transcribes continuous time optimal control problems into an NLP problem. In addition, since a mission profile can have varying vehicle dynamics and en-route imposed constraints, the optimal control problem formulation can be broken up into several "phases" with differing dynamics and/or varying initial/final constraints. Optimal trajectories are developed using several different performance costs in the optimal control formulation: minimum time, minimum time with control penalties, and maximum range. The resulting analysis demonstrates that optimal trajectories that meet specified mission parameters and constraints can be quickly determined and used for larger-scale operational and campaign planning and execution.

Attachment and family functioning in patients with internet addiction.

PubMed

Şenormancı, Ömer; Şenormancı, Güliz; Güçlü, Oya; Konkan, Ramazan

2014-01-01

Although the Internet is used effectively in many areas of life, some users experience problems because of over-use due to a lack of control. The diagnostic criteria for Internet addiction include disruptions in family relationships, but adequate data on the attachment styles and family functioning associated with this condition are limited. This study aimed to investigate the attachment styles and family functioning of patients with Internet addiction. The sample included 30 male patients consecutively admitted to the Bakırköy Mental Health and Research Hospital Internet Addiction Outpatient Clinic, who were diagnosed in clinical interviews as having Internet addiction according to Young's (1998) criteria. Thirty healthy males who were matched with the experimental group in terms of sociodemographic characteristics were included as control subjects. Both groups provided sociodemographic data and completed the Beck Depression Inventory (BDI), the Experiences in Close Relationships Questionnaire-r (ECR-r) and the Family Assessment Device (FAD). Patients with Internet addiction had higher BDI scores (P<.001) and higher attachment anxiety subscores on ECR-r (P<.001) compared with those in the control group. Patients with Internet addiction evaluated their family functioning as more negative and reported problems in every aspect addressed by the FAD. Scores on the FAD behaviour control, affective responsiveness, and problem-solving subscales (P<.05) and on the FAD communication, roles, and general functioning subscales (P<.001) were significantly higher in the patient compared with the control group. Patients with Internet addiction have more anxious attachment styles as well as prominent disruptions in family functioning. Thus, it may be important to evaluate the attachment styles and family functioning of patients with Internet addiction. Indeed, comprehensive treatment approaches including other family members may make important contributions to treatment success. Copyright © 2014 Elsevier Inc. All rights reserved.

Problem-Solving Deficits in Iranian People with Borderline Personality Disorder

PubMed Central

Akbari Dehaghi, Ashraf; Kaviani, Hossein; Tamanaeefar, Shima

2014-01-01

Objective: Interventions for people suffering from borderline personality disorder (BPD), such as dialectical behavior therapy, often include a problem-solving component. However, there is an absence of published studies examining the problem-solving abilities of this client group in Iran. The study compared inpatients and outpatients with BPD and a control group on problem-solving capabilities in an Iranian sample. It was hypothesized that patients with BPD would have more deficiencies in this area. Methods: Fifteen patients with BPD were compared to 15 healthy participants. Means-ends problem-solving task (MEPS) was used to measure problem-solving skills in both groups. Results: BPD group reported less effective strategies in solving problems as opposed to the healthy group. Compared to the control group, participants with BPD provided empirical support for the use of problem-solving interventions with people suffering from BPD. Conclusions: The findings supported the idea that a problem-solving intervention can be efficiently applied either as a stand-alone therapy or in conjunction with other available psychotherapies to treat people with BPD. PMID:25798169

Systems design study of the Pioneer Venus spacecraft. Volume 1. Technical analyses and tradeoffs, section 7 (part 3 of 4). [aerodynamic design problems for small probe reentry

NASA Technical Reports Server (NTRS)

1973-01-01

The aerodynamic design problems for the Pioneer Venus mission are discussed for a small probe shape that enters the atmosphere, and exhibits good stability for the subsonic portion of the flight. The problems discussed include: heat shield, structures and mechanisms, thermal control, decelerator, probe communication, data handling and command, and electric power.

Knowledge-based control for robot self-localization

NASA Technical Reports Server (NTRS)

Bennett, Bonnie Kathleen Holte

1993-01-01

Autonomous robot systems are being proposed for a variety of missions including the Mars rover/sample return mission. Prior to any other mission objectives being met, an autonomous robot must be able to determine its own location. This will be especially challenging because location sensors like GPS, which are available on Earth, will not be useful, nor will INS sensors because their drift is too large. Another approach to self-localization is required. In this paper, we describe a novel approach to localization by applying a problem solving methodology. The term 'problem solving' implies a computational technique based on logical representational and control steps. In this research, these steps are derived from observing experts solving localization problems. The objective is not specifically to simulate human expertise but rather to apply its techniques where appropriate for computational systems. In doing this, we describe a model for solving the problem and a system built on that model, called localization control and logic expert (LOCALE), which is a demonstration of concept for the approach and the model. The results of this work represent the first successful solution to high-level control aspects of the localization problem.

Finite element solution of optimal control problems with inequality constraints

NASA Technical Reports Server (NTRS)

Bless, Robert R.; Hodges, Dewey H.

1990-01-01

A finite-element method based on a weak Hamiltonian form of the necessary conditions is summarized for optimal control problems. Very crude shape functions (so simple that element numerical quadrature is not necessary) can be used to develop an efficient procedure for obtaining candidate solutions (i.e., those which satisfy all the necessary conditions) even for highly nonlinear problems. An extension of the formulation allowing for discontinuities in the states and derivatives of the states is given. A theory that includes control inequality constraints is fully developed. An advanced launch vehicle (ALV) model is presented. The model involves staging and control constraints, thus demonstrating the full power of the weak formulation to date. Numerical results are presented along with total elapsed computer time required to obtain the results. The speed and accuracy in obtaining the results make this method a strong candidate for a real-time guidance algorithm.

Interdisciplinary optimum design. [of aerospace structures

NASA Technical Reports Server (NTRS)

Sobieszczanski-Sobieski, Jaroslaw; Haftka, Raphael T.

1986-01-01

Problems related to interdisciplinary interactions in the design of a complex engineering systems are examined with reference to aerospace applications. The interdisciplinary optimization problems examined include those dealing with controls and structures, materials and structures, control and stability, structure and aerodynamics, and structure and thermodynamics. The discussion is illustrated by the following specific applications: integrated aerodynamic/structural optimization of glider wing; optimization of an antenna parabolic dish structure for minimum weight and prescribed emitted signal gain; and a multilevel optimization study of a transport aircraft.

Generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB.

PubMed

Lee, Leng-Feng; Umberger, Brian R

2016-01-01

Computer modeling, simulation and optimization are powerful tools that have seen increased use in biomechanics research. Dynamic optimizations can be categorized as either data-tracking or predictive problems. The data-tracking approach has been used extensively to address human movement problems of clinical relevance. The predictive approach also holds great promise, but has seen limited use in clinical applications. Enhanced software tools would facilitate the application of predictive musculoskeletal simulations to clinically-relevant research. The open-source software OpenSim provides tools for generating tracking simulations but not predictive simulations. However, OpenSim includes an extensive application programming interface that permits extending its capabilities with scripting languages such as MATLAB. In the work presented here, we combine the computational tools provided by MATLAB with the musculoskeletal modeling capabilities of OpenSim to create a framework for generating predictive simulations of musculoskeletal movement based on direct collocation optimal control techniques. In many cases, the direct collocation approach can be used to solve optimal control problems considerably faster than traditional shooting methods. Cyclical and discrete movement problems were solved using a simple 1 degree of freedom musculoskeletal model and a model of the human lower limb, respectively. The problems could be solved in reasonable amounts of time (several seconds to 1-2 hours) using the open-source IPOPT solver. The problems could also be solved using the fmincon solver that is included with MATLAB, but the computation times were excessively long for all but the smallest of problems. The performance advantage for IPOPT was derived primarily by exploiting sparsity in the constraints Jacobian. The framework presented here provides a powerful and flexible approach for generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB. This should allow researchers to more readily use predictive simulation as a tool to address clinical conditions that limit human mobility.

Generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB

PubMed Central

Lee, Leng-Feng

2016-01-01

Computer modeling, simulation and optimization are powerful tools that have seen increased use in biomechanics research. Dynamic optimizations can be categorized as either data-tracking or predictive problems. The data-tracking approach has been used extensively to address human movement problems of clinical relevance. The predictive approach also holds great promise, but has seen limited use in clinical applications. Enhanced software tools would facilitate the application of predictive musculoskeletal simulations to clinically-relevant research. The open-source software OpenSim provides tools for generating tracking simulations but not predictive simulations. However, OpenSim includes an extensive application programming interface that permits extending its capabilities with scripting languages such as MATLAB. In the work presented here, we combine the computational tools provided by MATLAB with the musculoskeletal modeling capabilities of OpenSim to create a framework for generating predictive simulations of musculoskeletal movement based on direct collocation optimal control techniques. In many cases, the direct collocation approach can be used to solve optimal control problems considerably faster than traditional shooting methods. Cyclical and discrete movement problems were solved using a simple 1 degree of freedom musculoskeletal model and a model of the human lower limb, respectively. The problems could be solved in reasonable amounts of time (several seconds to 1–2 hours) using the open-source IPOPT solver. The problems could also be solved using the fmincon solver that is included with MATLAB, but the computation times were excessively long for all but the smallest of problems. The performance advantage for IPOPT was derived primarily by exploiting sparsity in the constraints Jacobian. The framework presented here provides a powerful and flexible approach for generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB. This should allow researchers to more readily use predictive simulation as a tool to address clinical conditions that limit human mobility. PMID:26835184

On the Teaching of a Self-Modification Course

ERIC Educational Resources Information Center

Tasto, Donald L.

1976-01-01

Discusses teaching techniques, course content, strategies, and problems of teaching a behavior modification course to university students. Course target areas include subjects such as anxiety control, fear elimination, weight control, smoking reduction, interpersonal interaction, assertiveness, and exercise maintenance. (Author/DB)

Gyrodampers for large space structures

NASA Technical Reports Server (NTRS)

Aubrun, J. N.; Margulies, G.

1979-01-01

The problem of controlling the vibrations of a large space structures by the use of actively augmented damping devices distributed throughout the structure is addressed. The gyrodamper which consists of a set of single gimbal control moment gyros which are actively controlled to extract the structural vibratory energy through the local rotational deformations of the structure, is described and analyzed. Various linear and nonlinear dynamic simulations of gyrodamped beams are shown, including results on self-induced vibrations due to sensor noise and rotor imbalance. The complete nonlinear dynamic equations are included. The problem of designing and sizing a system of gyrodampers for a given structure, or extrapolating results for one gyrodamped structure to another is solved in terms of scaling laws. Novel scaling laws for gyro systems are derived, based upon fundamental physical principles, and various examples are given.

Approximation theory for LQG (Linear-Quadratic-Gaussian) optimal control of flexible structures

NASA Technical Reports Server (NTRS)

Gibson, J. S.; Adamian, A.

1988-01-01

An approximation theory is presented for the LQG (Linear-Quadratic-Gaussian) optimal control problem for flexible structures whose distributed models have bounded input and output operators. The main purpose of the theory is to guide the design of finite dimensional compensators that approximate closely the optimal compensator. The optimal LQG problem separates into an optimal linear-quadratic regulator problem and an optimal state estimation problem. The solution of the former problem lies in the solution to an infinite dimensional Riccati operator equation. The approximation scheme approximates the infinite dimensional LQG problem with a sequence of finite dimensional LQG problems defined for a sequence of finite dimensional, usually finite element or modal, approximations of the distributed model of the structure. Two Riccati matrix equations determine the solution to each approximating problem. The finite dimensional equations for numerical approximation are developed, including formulas for converting matrix control and estimator gains to their functional representation to allow comparison of gains based on different orders of approximation. Convergence of the approximating control and estimator gains and of the corresponding finite dimensional compensators is studied. Also, convergence and stability of the closed-loop systems produced with the finite dimensional compensators are discussed. The convergence theory is based on the convergence of the solutions of the finite dimensional Riccati equations to the solutions of the infinite dimensional Riccati equations. A numerical example with a flexible beam, a rotating rigid body, and a lumped mass is given.

Intelligent on-line fault tolerant control for unanticipated catastrophic failures.

PubMed

Yen, Gary G; Ho, Liang-Wei

2004-10-01

As dynamic systems become increasingly complex, experience rapidly changing environments, and encounter a greater variety of unexpected component failures, solving the control problems of such systems is a grand challenge for control engineers. Traditional control design techniques are not adequate to cope with these systems, which may suffer from unanticipated dynamic failures. In this research work, we investigate the on-line fault tolerant control problem and propose an intelligent on-line control strategy to handle the desired trajectories tracking problem for systems suffering from various unanticipated catastrophic faults. Through theoretical analysis, the sufficient condition of system stability has been derived and two different on-line control laws have been developed. The approach of the proposed intelligent control strategy is to continuously monitor the system performance and identify what the system's current state is by using a fault detection method based upon our best knowledge of the nominal system and nominal controller. Once a fault is detected, the proposed intelligent controller will adjust its control signal to compensate for the unknown system failure dynamics by using an artificial neural network as an on-line estimator to approximate the unexpected and unknown failure dynamics. The first control law is derived directly from the Lyapunov stability theory, while the second control law is derived based upon the discrete-time sliding mode control technique. Both control laws have been implemented in a variety of failure scenarios to validate the proposed intelligent control scheme. The simulation results, including a three-tank benchmark problem, comply with theoretical analysis and demonstrate a significant improvement in trajectory following performance based upon the proposed intelligent control strategy.

Community Violence Exposure and Conduct Problems in Children and Adolescents with Conduct Disorder and Healthy Controls

PubMed Central

Kersten, Linda; Vriends, Noortje; Steppan, Martin; Raschle, Nora M.; Praetzlich, Martin; Oldenhof, Helena; Vermeiren, Robert; Jansen, Lucres; Ackermann, Katharina; Bernhard, Anka; Martinelli, Anne; Gonzalez-Madruga, Karen; Puzzo, Ignazio; Wells, Amy; Rogers, Jack C.; Clanton, Roberta; Baker, Rosalind H.; Grisley, Liam; Baumann, Sarah; Gundlach, Malou; Kohls, Gregor; Gonzalez-Torres, Miguel A.; Sesma-Pardo, Eva; Dochnal, Roberta; Lazaratou, Helen; Kalogerakis, Zacharias; Bigorra Gualba, Aitana; Smaragdi, Areti; Siklósi, Réka; Dikeos, Dimitris; Hervás, Amaia; Fernández-Rivas, Aranzazu; De Brito, Stephane A.; Konrad, Kerstin; Herpertz-Dahlmann, Beate; Fairchild, Graeme; Freitag, Christine M.; Popma, Arne; Kieser, Meinhard; Stadler, Christina

2017-01-01

Exposure to community violence through witnessing or being directly victimized has been associated with conduct problems in a range of studies. However, the relationship between community violence exposure (CVE) and conduct problems has never been studied separately in healthy individuals and individuals with conduct disorder (CD). Therefore, it is not clear whether the association between CVE and conduct problems is due to confounding factors, because those with high conduct problems also tend to live in more violent neighborhoods, i.e., an ecological fallacy. Hence, the aim of the present study was: (1) to investigate whether the association between recent CVE and current conduct problems holds true for healthy controls as well as adolescents with a diagnosis of CD; (2) to examine whether the association is stable in both groups when including effects of aggression subtypes (proactive/reactive aggression), age, gender, site and socioeconomic status (SES); and (3) to test whether proactive or reactive aggression mediate the link between CVE and conduct problems. Data from 1178 children and adolescents (62% female; 44% CD) aged between 9 years and 18 years from seven European countries were analyzed. Conduct problems were assessed using the Kiddie-Schedule of Affective Disorders and Schizophrenia diagnostic interview. Information about CVE and aggression subtypes was obtained using self-report questionnaires (Social and Health Assessment and Reactive-Proactive aggression Questionnaire (RPQ), respectively). The association between witnessing community violence and conduct problems was significant in both groups (adolescents with CD and healthy controls). The association was also stable after examining the mediating effects of aggression subtypes while including moderating effects of age, gender and SES and controlling for effects of site in both groups. There were no clear differences between the groups in the strength of the association between witnessing violence and conduct problems. However, we found evidence for a ceiling effect, i.e., individuals with very high levels of conduct problems could not show a further increase if exposed to CVE and vice versa. Results indicate that there was no evidence for an ecological fallacy being the primary cause of the association, i.e., CVE must be considered a valid risk factor in the etiology of CD. PMID:29163090

Approximately adaptive neural cooperative control for nonlinear multiagent systems with performance guarantee

NASA Astrophysics Data System (ADS)

Wang, Jing; Yang, Tianyu; Staskevich, Gennady; Abbe, Brian

2017-04-01

This paper studies the cooperative control problem for a class of multiagent dynamical systems with partially unknown nonlinear system dynamics. In particular, the control objective is to solve the state consensus problem for multiagent systems based on the minimisation of certain cost functions for individual agents. Under the assumption that there exist admissible cooperative controls for such class of multiagent systems, the formulated problem is solved through finding the optimal cooperative control using the approximate dynamic programming and reinforcement learning approach. With the aid of neural network parameterisation and online adaptive learning, our method renders a practically implementable approximately adaptive neural cooperative control for multiagent systems. Specifically, based on the Bellman's principle of optimality, the Hamilton-Jacobi-Bellman (HJB) equation for multiagent systems is first derived. We then propose an approximately adaptive policy iteration algorithm for multiagent cooperative control based on neural network approximation of the value functions. The convergence of the proposed algorithm is rigorously proved using the contraction mapping method. The simulation results are included to validate the effectiveness of the proposed algorithm.

Nonlinear robust control of hypersonic aircrafts with interactions between flight dynamics and propulsion systems.

PubMed

Li, Zhaoying; Zhou, Wenjie; Liu, Hao

2016-09-01

This paper addresses the nonlinear robust tracking controller design problem for hypersonic vehicles. This problem is challenging due to strong coupling between the aerodynamics and the propulsion system, and the uncertainties involved in the vehicle dynamics including parametric uncertainties, unmodeled model uncertainties, and external disturbances. By utilizing the feedback linearization technique, a linear tracking error system is established with prescribed references. For the linear model, a robust controller is proposed based on the signal compensation theory to guarantee that the tracking error dynamics is robustly stable. Numerical simulation results are given to show the advantages of the proposed nonlinear robust control method, compared to the robust loop-shaping control approach. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Disturbance observer based model predictive control for accurate atmospheric entry of spacecraft

NASA Astrophysics Data System (ADS)

Wu, Chao; Yang, Jun; Li, Shihua; Li, Qi; Guo, Lei

2018-05-01

Facing the complex aerodynamic environment of Mars atmosphere, a composite atmospheric entry trajectory tracking strategy is investigated in this paper. External disturbances, initial states uncertainties and aerodynamic parameters uncertainties are the main problems. The composite strategy is designed to solve these problems and improve the accuracy of Mars atmospheric entry. This strategy includes a model predictive control for optimized trajectory tracking performance, as well as a disturbance observer based feedforward compensation for external disturbances and uncertainties attenuation. 500-run Monte Carlo simulations show that the proposed composite control scheme achieves more precise Mars atmospheric entry (3.8 km parachute deployment point distribution error) than the baseline control scheme (8.4 km) and integral control scheme (5.8 km).

Impulsive Control for Continuous-Time Markov Decision Processes: A Linear Programming Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dufour, F., E-mail: dufour@math.u-bordeaux1.fr; Piunovskiy, A. B., E-mail: piunov@liv.ac.uk

2016-08-15

In this paper, we investigate an optimization problem for continuous-time Markov decision processes with both impulsive and continuous controls. We consider the so-called constrained problem where the objective of the controller is to minimize a total expected discounted optimality criterion associated with a cost rate function while keeping other performance criteria of the same form, but associated with different cost rate functions, below some given bounds. Our model allows multiple impulses at the same time moment. The main objective of this work is to study the associated linear program defined on a space of measures including the occupation measures ofmore » the controlled process and to provide sufficient conditions to ensure the existence of an optimal control.« less

Flight investigation of manual and automatic VTOL decelerating instrument approaches and landings

NASA Technical Reports Server (NTRS)

Kelly, J. R.; Niessen, F. R.; Thibodeaux, J. J.; Yenni, K. R.; Garren, J. F., Jr.

1974-01-01

A flight investigation was undertaken to study the problems associated with manual and automatic control of steep, decelerating instrument approaches and landings under simulated instrument conditions. The study was conducted with a research helicopter equipped with a three-cue flight-director indicator. The scope of the investigation included variations in the flight-director control laws, glide-path angle, deceleration profile, and control response characteristics. Investigation of the automatic-control problem resulted in the first automated approach and landing to a predetermined spot ever accomplished with a helicopter. Although well-controlled approaches and landings could be performed manually with the flight-director concept, pilot comments indicated the need for a better display which would more effectively integrate command and situation information.

Experiential avoidance mediates the association between thought suppression and mindfulness with problem gambling.

PubMed

Riley, Ben

2014-03-01

Experiential avoidance (EA) has been shown to be an important etiological and maintenance factor in a wide range psychopathology that includes addictive, anxiety, depressive and impulse control disorders. One common form of EA is thought suppression. Problem gambling causes enormous problems for afflicted individuals and has major social costs for their families and the community. Despite increasing interest in the contribution of EA to a broad range of psychological problems, its association with problem gambling has not previously been empirically investigated. The purpose of this cross-sectional study was to investigate the relationship between EA, thought suppression, and mindfulness among a group of 103 treatment seeking problem gamblers. Of particular interest was the extent to which EA accounted for the relationships between problem gambling and the two theoretically opposing constructs: thought suppression and mindfulness. Results showed EA was predictive of problem gambling. Thought suppression was positively associated and mindfulness negatively associated with problem gambling, and these relationships were mediated by EA. Directions for future research are suggested which include the application of treatments for problem gambling that undermine EA, such as acceptance and mindfulness based therapies.

How to Identify and Control Water Weeds and Algae.

ERIC Educational Resources Information Center

Applied Biochemists, Inc., Mequon, WI.

Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

Research directions in large scale systems and decentralized control

NASA Technical Reports Server (NTRS)

Tenney, R. R.

1980-01-01

Control theory provides a well established framework for dealing with automatic decision problems and a set of techniques for automatic decision making which exploit special structure, but it does not deal well with complexity. The potential exists for combining control theoretic and knowledge based concepts into a unified approach. The elements of control theory are diagrammed, including modern control and large scale systems.

COLLABORATIVE RESEARCH ON URBAN BEST MANAGEMENT PRACTICES

EPA Science Inventory

Storm driven wet weather flow (WWF) which includes combined sewer and sanitary sewer overflows and stormwater discharges are a leading cause of water-quality impairment. Problem constituents in WWF include pathogens, solids, nutrients, and toxicants. New technologies to control...

Internet Plagiarism: An Agenda for Staff Inservice and Student Awareness.

ERIC Educational Resources Information Center

Lincoln, Margaret

2002-01-01

Discusses Internet plagiarism and includes an outline for a presentation that library media specialists can use with teachers. Highlights include an overview of the problem; helping teachers recognize the signs; pinpointing the source, including the use of search engines and Web sites; and prevention, including more control over the research…

Optimal guidance law development for an advanced launch system

NASA Technical Reports Server (NTRS)

Calise, Anthony J.; Hodges, Dewey H.

1990-01-01

A regular perturbation analysis is presented. Closed-loop simulations were performed with a first order correction including all of the atmospheric terms. In addition, a method was developed for independently checking the accuracy of the analysis and the rather extensive programming required to implement the complete first order correction with all of the aerodynamic effects included. This amounted to developing an equivalent Hamiltonian computed from the first order analysis. A second order correction was also completed for the neglected spherical Earth and back-pressure effects. Finally, an analysis was begun on a method for dealing with control inequality constraints. The results on including higher order corrections do show some improvement for this application; however, it is not known at this stage if significant improvement will result when the aerodynamic forces are included. The weak formulation for solving optimal problems was extended in order to account for state inequality constraints. The formulation was tested on three example problems and numerical results were compared to the exact solutions. Development of a general purpose computational environment for the solution of a large class of optimal control problems is under way. An example, along with the necessary input and the output, is given.

Terminal Sliding Modes In Nonlinear Control Systems

NASA Technical Reports Server (NTRS)

Venkataraman, Subramanian T.; Gulati, Sandeep

1993-01-01

Control systems of proposed type called "terminal controllers" offers increased precision and stability of robotic operations in presence of unknown and/or changing parameters. Systems include special computer hardware and software implementing novel control laws involving terminal sliding modes of motion: closed-loop combination of robot and terminal controller converge, in finite time, to point of stable equilibrium in abstract space of velocity and/or position coordinates applicable to particular control problem.

IFLA General Conference, 1984. Bibliographic Control Division. Sections on Bibliography, Cataloging, and Classification. Part 2. Papers.

ERIC Educational Resources Information Center

International Federation of Library Associations, The Hague (Netherlands).

Papers on cataloging and national bibliography presented at the 1984 general conference of IFLA include: (1) "Pratiques et Problemes de Catalogage au Senegal" (Cataloging Practices and Problems in Senegal) (Marietou Diop Diongue, Senegal); (2) "The Consequences of New Technologies in Classification and Subject Cataloging in Third…

Treatment Adherence, Competence, and Outcome in Individual and Family Therapy for Adolescent Behavior Problems

ERIC Educational Resources Information Center

Hogue, Aaron; Henderson, Craig E.; Dauber, Sarah; Barajas, Priscilla C.; Fried, Adam; Liddle, Howard A.

2008-01-01

This study examined the impact of treatment adherence and therapist competence on treatment outcome in a controlled trial of individual cognitive-behavioral therapy (CBT) and multidimensional family therapy (MDFT) for adolescent substance use and related behavior problems. Participants included 136 adolescents (62 CBT, 74 MDFT) assessed at intake,…

Problem-Based Learning Method: Secondary Education 10th Grade Chemistry Course Mixtures Topic

ERIC Educational Resources Information Center

Üce, Musa; Ates, Ismail

2016-01-01

In this research; aim was determining student achievement by comparing problem-based learning method with teacher-centered traditional method of teaching 10th grade chemistry lesson mixtures topic. Pretest-posttest control group research design is implemented. Research sample includes; two classes of (total of 48 students) an Anatolian High School…

Travels towards Problem Based Learning in Medical Education (VPBL).

ERIC Educational Resources Information Center

Bowdish, Bruce E.; Chauvin, Sheila W.; Kreisman, Norman; Britt, Mike

2003-01-01

Reports results of an investigation of the effectiveness of a prototype virtual problem-based learning (VPBL) exercise delivered via the World Wide Web to first year medical students. Compares the VPBL and a text-based version of the same exercise on students' achievement and examines instructional design issues including learner control and…

[A control study of a school-based life skills education on prevention of behavior problems in third-grade schoolchildren].

PubMed

Lin, Hong; Wang, Yu-feng; Wu, Ye-ping

2007-06-18

To evaluate the effectiveness on the prevention of behavior problems of life skills education combining school-based and parent-involved approaches for third-grade students in China. This research was targeted at the population of third-grade children in two elementary schools in Qinhuangdao City, Hebei Province. Nine regular school classrooms were randomly divided into three groups: the intervention group (n=208), internal control group (n=209) and external control group (n=204). The intervention included 26-hour competence promotion for students and 5-hour parent training. The Rutter Scale by parent and teacher were used to evaluate the effects at pretest, posttest and 6-month follow-up. Improvement was observed among children in the intervention group than those in the control groups. The statistical difference was significant (P<0.05).1.The prevalence of total behavior problems, antisocial behavior and neurotic behavior problem at home: At termination, the prevalence in intervention group(11.2%,3.6% and 6.1%)was lower (except neurotic behavior) than those in internal control group (19.4%,5.6% and 6.1%)and external control group (18.9%,8.9% and 5.3%). At 6-month follow-up, the prevalence in intervention group (10.2%,2.5% and 3.6%)was still lower than those in internal control group (17.2%,6.8% and 6.8%)and external control group (17.8%,7.8% and 6.7%).2. The prevalence of total behavior problems and antisocial behavior problem at school: At termination, the prevalence in intervention group(5.3% and 4.3%)was lower than those in internal control group(10.1% and 7.7%)and external control group(14.9% and 12.4%). At 6-month follow-up, the prevalence in intervention group(2.9% and 2.4%)was still lower than those in internal control group (10.2% and 9.7%)and external control group(11.3% and 10.3%). Life skills education could reduce the children's home and school behavior problems, especially for antisocial behavior. The effects of intervention maintained during the 6-month follow-up study.

Problem coping skills, psychosocial adversities and mental health problems in children and adolescents as predictors of criminal outcomes in young adulthood.

PubMed

Aebi, Marcel; Giger, Joël; Plattner, Belinda; Metzke, Christa Winkler; Steinhausen, Hans-Christoph

2014-05-01

The purpose of this study was to test child and adolescent psychosocial and psychopathological risk factors as predictors of adult criminal outcomes in a Swiss community sample. In particular, the role of active and avoidant problem coping in youths was analysed. Prevalence rates of young adult crime convictions based on register data were calculated. Univariate and multivariate logistic regressions were used to analyse the prediction of adult criminal convictions 15 years after assessment in a large Swiss community sample of children and adolescents (n = 1,086). Risk factors assessed in childhood and adolescence included socio-economic status (SES), migration background, perceived parental behaviour, familial and other social stressors, coping styles, externalizing and internalizing problems and drug abuse including problematic alcohol consumption. The rate of any young adult conviction was 10.1 %. Besides externalizing problems and problematic alcohol consumption, the presence of any criminal conviction in young adulthood was predicted by low SES and avoidant coping even after controlling for the effects of externalizing problems and problematic alcohol use. The other predictors were significant only when externalizing behaviours and problematic alcohol use were not controlled. In addition to child and adolescent externalizing behaviour problems and substance use, low SES and inadequate problem-solving skills, in terms of avoidant coping, are major risk factors of young adult criminal outcomes and need to be considered in forensic research and criminal prevention programs.

Instability in Rotating Machinery

NASA Technical Reports Server (NTRS)

1985-01-01

The proceedings contain 45 papers on a wide range of subjects including flow generated instabilities in fluid flow machines, cracked shaft detection, case histories of instability phenomena in compressors, turbines, and pumps, vibration control in turbomachinery (including antiswirl techniques), and the simulation and estimation of destabilizing forces in rotating machines. The symposium was held to serve as an update on the understanding and control of rotating machinery instability problems.

Enabling Controlling Complex Networks with Local Topological Information.

PubMed

Li, Guoqi; Deng, Lei; Xiao, Gaoxi; Tang, Pei; Wen, Changyun; Hu, Wuhua; Pei, Jing; Shi, Luping; Stanley, H Eugene

2018-03-15

Complex networks characterize the nature of internal/external interactions in real-world systems including social, economic, biological, ecological, and technological networks. Two issues keep as obstacles to fulfilling control of large-scale networks: structural controllability which describes the ability to guide a dynamical system from any initial state to any desired final state in finite time, with a suitable choice of inputs; and optimal control, which is a typical control approach to minimize the cost for driving the network to a predefined state with a given number of control inputs. For large complex networks without global information of network topology, both problems remain essentially open. Here we combine graph theory and control theory for tackling the two problems in one go, using only local network topology information. For the structural controllability problem, a distributed local-game matching method is proposed, where every node plays a simple Bayesian game with local information and local interactions with adjacent nodes, ensuring a suboptimal solution at a linear complexity. Starring from any structural controllability solution, a minimizing longest control path method can efficiently reach a good solution for the optimal control in large networks. Our results provide solutions for distributed complex network control and demonstrate a way to link the structural controllability and optimal control together.

Topology Control and Routing in Ad Hoc Networks

NASA Astrophysics Data System (ADS)

Carr-Motyckova, Lenka; Navarra, Alfredo; Johansson, Tomas; Unger, Walter

Mobile nodes with the ability to communicate with radio signals may form an ad hoc network. In this chapter special problems arising for these ad hoc networks are considered. These include range control, the reduction of interferences, regulation of power consumption, and localization.

Prospective relations between family conflict and adolescent maladjustment: security in the family system as a mediating process.

PubMed

Cummings, E Mark; Koss, Kalsea J; Davies, Patrick T

2015-04-01

Conflict in specific family systems (e.g., interparental, parent-child) has been implicated in the development of a host of adjustment problems in adolescence, but little is known about the impact of family conflict involving multiple family systems. Furthermore, questions remain about the effects of family conflict on symptoms of specific disorders and adjustment problems and the processes mediating these effects. The present study prospectively examines the impact of family conflict and emotional security about the family system on adolescent symptoms of specific disorders and adjustment problems, including the development of symptoms of anxiety, depression, conduct problems, and peer problems. Security in the family system was examined as a mediator of these relations. Participants included 295 mother-father-adolescent families (149 girls) participating across three annual time points (grades 7-9). Including auto-regressive controls for initial levels of emotional insecurity and multiple adjustment problems (T1), higher-order emotional insecurity about the family system (T2) mediated relations between T1 family conflict and T3 peer problems, anxiety, and depressive symptoms. Further analyses supported specific patterns of emotional security/insecurity (i.e., security, disengagement, preoccupation) as mediators between family conflict and specific domains of adolescent adjustment. Family conflict was thus found to prospectively predict the development of symptoms of multiple specific adjustment problems, including symptoms of depression, anxiety, conduct problems, and peer problems, by elevating in in adolescent's emotional insecurity about the family system. The clinical implications of these findings are considered.

Consideration of computer limitations in implementing on-line controls. M.S. Thesis

NASA Technical Reports Server (NTRS)

Roberts, G. K.

1976-01-01

A formal statement of the optimal control problem which includes the interval of dicretization as an optimization parameter, and extend this to include selection of a control algorithm as part of the optimization procedure, is formulated. The performance of the scalar linear system depends on the discretization interval. Discrete-time versions of the output feedback regulator and an optimal compensator, and the use of these results in presenting an example of a system for which fast partial-state-feedback control better minimizes a quadratic cost than either a full-state feedback control or a compensator, are developed.

Three axis electronic flight motion simulator real time control system design and implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Zhiyuan; Miao, Zhonghua, E-mail: zhonghua-miao@163.com; Wang, Xiaohua

2014-12-15

A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

Three axis electronic flight motion simulator real time control system design and implementation.

PubMed

Gao, Zhiyuan; Miao, Zhonghua; Wang, Xuyong; Wang, Xiaohua

2014-12-01

A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

A numerical method for solving a nonlinear 2-D optimal control problem with the classical diffusion equation

NASA Astrophysics Data System (ADS)

Mamehrashi, K.; Yousefi, S. A.

2017-02-01

This paper presents a numerical solution for solving a nonlinear 2-D optimal control problem (2DOP). The performance index of a nonlinear 2DOP is described with a state and a control function. Furthermore, dynamic constraint of the system is given by a classical diffusion equation. It is preferred to use the Ritz method for finding the numerical solution of the problem. The method is based upon the Legendre polynomial basis. By using this method, the given optimisation nonlinear 2DOP reduces to the problem of solving a system of algebraic equations. The benefit of the method is that it provides greater flexibility in which the given initial and boundary conditions of the problem are imposed. Moreover, compared with the eigenfunction method, the satisfactory results are obtained only in a small number of polynomials order. This numerical approach is applicable and effective for such a kind of nonlinear 2DOP. The convergence of the method is extensively discussed and finally two illustrative examples are included to observe the validity and applicability of the new technique developed in the current work.

Contribution of Equal-Sign Instruction beyond Word-Problem Tutoring for Third-Grade Students with Mathematics Difficulty.

PubMed

Powell, Sarah R; Fuchs, Lynn S

2010-05-01

Elementary school students often misinterpret the equal sign (=) as an operational rather than a relational symbol. Such misunderstanding is problematic because solving equations with missing numbers may be important for higher-order mathematics skills including word problems. Research indicates equal-sign instruction can alter how typically-developing students use the equal sign, but no study has examined effects for students with mathematics difficulty (MD) or how equal-sign instruction contributes to word-problem skill for students with or without MD. The present study assessed the efficacy of equal-sign instruction within word-problem tutoring. Third-grade students with MD (n = 80) were assigned to word-problem tutoring, word-problem tutoring plus equal-sign instruction (combined) tutoring, or no-tutoring control. Combined tutoring produced better improvement on equal sign tasks and open equations compared to the other 2 conditions. On certain forms of word problems, combined tutoring but not word-problem tutoring alone produced better improvement than control. When compared at posttest to 3(rd)-grade students without MD on equal sign tasks and open equations, only combined tutoring students with MD performed comparably.

Incremental planning to control a blackboard-based problem solver

NASA Technical Reports Server (NTRS)

Durfee, E. H.; Lesser, V. R.

1987-01-01

To control problem solving activity, a planner must resolve uncertainty about which specific long-term goals (solutions) to pursue and about which sequences of actions will best achieve those goals. A planner is described that abstracts the problem solving state to recognize possible competing and compatible solutions and to roughly predict the importance and expense of developing these solutions. With this information, the planner plans sequences of problem solving activities that most efficiently resolve its uncertainty about which of the possible solutions to work toward. The planner only details actions for the near future because the results of these actions will influence how (and whether) a plan should be pursued. As problem solving proceeds, the planner adds new details to the plan incrementally, and monitors and repairs the plan to insure it achieves its goals whenever possible. Through experiments, researchers illustrate how these new mechanisms significantly improve problem solving decisions and reduce overall computation. They briefly discuss current research directions, including how these mechanisms can improve a problem solver's real-time response and can enhance cooperation in a distributed problem solving network.

Optimal control in adaptive optics modeling of nonlinear systems

NASA Astrophysics Data System (ADS)

Herrmann, J.

The problem of using an adaptive optics system to correct for nonlinear effects like thermal blooming is addressed using a model containing nonlinear lenses through which Gaussian beams are propagated. The best correction of this nonlinear system can be formulated as a deterministic open loop optimal control problem. This treatment gives a limit for the best possible correction. Aspects of adaptive control and servo systems are not included at this stage. An attempt is made to determine that control in the transmitter plane which minimizes the time averaged area or maximizes the fluence in the target plane. The standard minimization procedure leads to a two-point-boundary-value problem, which is ill-conditioned in the case. The optimal control problem was solved using an iterative gradient technique. An instantaneous correction is introduced and compared with the optimal correction. The results of the calculations show that for short times or weak nonlinearities the instantaneous correction is close to the optimal correction, but that for long times and strong nonlinearities a large difference develops between the two types of correction. For these cases the steady state correction becomes better than the instantaneous correction and approaches the optimum correction.

Common sense behavior modification: a guide for practitioners.

PubMed

Horwitz, Debra F; Pike, Amy L

2014-05-01

Behavior problems are often given as a reason for pet relinquishment to shelters. When presented with any behavior problem, veterinarians should perform a thorough physical examination (including neurologic and orthopedic examination) and a minimum database, including a complete blood cell count, chemistry panel, and total T4 and free T4 by equilibrium dialysis if values are low to rule out any medical contributions. Veterinarians should be a source of information regarding management, safety, and basic behavior modification for common behavior problems. Additionally, various control devices offer pet owners the ability to better manage their pets in difficult situations. Copyright © 2014 Elsevier Inc. All rights reserved.

The prevalence of foot problems in older women: a cause for concern.

PubMed

Dawson, Jill; Thorogood, Margaret; Marks, Sally-Anne; Juszczak, Ed; Dodd, Chris; Lavis, Grahame; Fitzpatrick, Ray

2002-06-01

Painful feet are an extremely common problem amongst older women. Such problems increase the risk of falls and hamper mobility. The aetiology of painful and deformed feet is poorly understood. Data were obtained during a pilot case-control study about past high heel usage in women, in relation to osteoarthritis of the knee. A total of 127 women aged 50-70 were interviewed (31 cases, 96 controls); case-control sets were matched for age. The following information was obtained about footwear: (1) age when first wore shoes with heels 1, 2 and 3 inches high; (2) height of heels worn for work; (3) maximum height of heels worn regularly for work, going out socially and for dancing, in 10-year age bands. Information about work-related activities and lifetime occupational history was gathered using a Life-Grid. The interview included a foot inspection. Foot problems, particularly foot arthritis, affected considerably more cases than controls (45 per cent versus 16 per cent, p = 0.001) and was considered a confounder. Cases were therefore excluded from subsequent analyses. Amongst controls, the prevalence of any foot problems was very high (83 per cent). All women had regularly worn one inch heels and few (8 per cent) had never worn 2 inch heels. Foot problems were significantly associated with a history of wearing relatively lower heels. Few work activities were related to foot problems; regular lifting was associated with foot pain (p = 0.03). Most women in this age-group have been exposed to high-heeled shoes over many years, making aetiological research difficult in this area. Foot pain and deformities are widespread. The relationship between footwear, occupational activities and foot problems is a complex one that deserves considerably more research.

Female adolescents with severe substance and conduct problems have substantially less brain gray matter volume.

PubMed

Dalwani, Manish S; McMahon, Mary Agnes; Mikulich-Gilbertson, Susan K; Young, Susan E; Regner, Michael F; Raymond, Kristen M; McWilliams, Shannon K; Banich, Marie T; Tanabe, Jody L; Crowley, Thomas J; Sakai, Joseph T

2015-01-01

Structural neuroimaging studies have demonstrated lower regional gray matter volume in adolescents with severe substance and conduct problems. These research studies, including ours, have generally focused on male-only or mixed-sex samples of adolescents with conduct and/or substance problems. Here we compare gray matter volume between female adolescents with severe substance and conduct problems and female healthy controls of similar ages. Female adolescents with severe substance and conduct problems will show significantly less gray matter volume in frontal regions critical to inhibition (i.e. dorsolateral prefrontal cortex and ventrolateral prefrontal cortex), conflict processing (i.e., anterior cingulate), valuation of expected outcomes (i.e., medial orbitofrontal cortex) and the dopamine reward system (i.e. striatum). We conducted whole-brain voxel-based morphometric comparison of structural MR images of 22 patients (14-18 years) with severe substance and conduct problems and 21 controls of similar age using statistical parametric mapping (SPM) and voxel-based morphometric (VBM8) toolbox. We tested group differences in regional gray matter volume with analyses of covariance, adjusting for age and IQ at p<0.05, corrected for multiple comparisons at whole-brain cluster-level threshold. Female adolescents with severe substance and conduct problems compared to controls showed significantly less gray matter volume in right dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, medial orbitofrontal cortex, anterior cingulate, bilateral somatosensory cortex, left supramarginal gyrus, and bilateral angular gyrus. Considering the entire brain, patients had 9.5% less overall gray matter volume compared to controls. Female adolescents with severe substance and conduct problems in comparison to similarly aged female healthy controls showed substantially lower gray matter volume in brain regions involved in inhibition, conflict processing, valuation of outcomes, decision-making, reward, risk-taking, and rule-breaking antisocial behavior.

Design and implementation of a novel modal space active force control concept for spatial multi-DOF parallel robotic manipulators actuated by electrical actuators.

PubMed

Yang, Chifu; Zhao, Jinsong; Li, Liyi; Agrawal, Sunil K

2018-01-01

Robotic spine brace based on parallel-actuated robotic system is a new device for treatment and sensing of scoliosis, however, the strong dynamic coupling and anisotropy problem of parallel manipulators result in accuracy loss of rehabilitation force control, including big error in direction and value of force. A novel active force control strategy named modal space force control is proposed to solve these problems. Considering the electrical driven system and contact environment, the mathematical model of spatial parallel manipulator is built. The strong dynamic coupling problem in force field is described via experiments as well as the anisotropy problem of work space of parallel manipulators. The effects of dynamic coupling on control design and performances are discussed, and the influences of anisotropy on accuracy are also addressed. With mass/inertia matrix and stiffness matrix of parallel manipulators, a modal matrix can be calculated by using eigenvalue decomposition. Making use of the orthogonality of modal matrix with mass matrix of parallel manipulators, the strong coupled dynamic equations expressed in work space or joint space of parallel manipulator may be transformed into decoupled equations formulated in modal space. According to this property, each force control channel is independent of others in the modal space, thus we proposed modal space force control concept which means the force controller is designed in modal space. A modal space active force control is designed and implemented with only a simple PID controller employed as exampled control method to show the differences, uniqueness, and benefits of modal space force control. Simulation and experimental results show that the proposed modal space force control concept can effectively overcome the effects of the strong dynamic coupling and anisotropy problem in the physical space, and modal space force control is thus a very useful control framework, which is better than the current joint space control and work space control. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Apollo experience report: Guidance and control systems - Digital autopilot design development

NASA Technical Reports Server (NTRS)

Peters, W. H.; Cox, K. J.

1973-01-01

The development of the Apollo digital autopilots (the primary attitude control systems that were used for all phases of the lunar landing mission) is summarized. This report includes design requirements, design constraints, and design philosophy. The development-process functions and the essential information flow paths are identified. Specific problem areas that existed during the development are included. A discussion is also presented on the benefits inherent in mechanizing attitude-controller logic and dynamic compensation in a digital computer.

A Population-Based Study of Gastroesophageal Reflux Disease and Sleep Problems in Elderly Twins

PubMed Central

Lindam, Anna; Jansson, Catarina; Nordenstedt, Helena; Pedersen, Nancy L.; Lagergren, Jesper

2012-01-01

Background & Aims Previous studies indicate an association between sleep problems and gastroesophageal reflux disease (GERD). Although both these conditions separately have moderate heritabilities, confounding by genetic factors has not previously been taken into account. This study aimed to reveal the association between sleep problems and GERD, while adjusting for heredity and other potential confounding factors. Methods This cross-sectional population-based study included all 8,014 same-sexed twins of at least 65 years of age and born in Sweden between 1886 and 1958, who participated in telephone interviews in 1998–2002. Three logistic regression models were used 1) external control analysis, 2) within-pair co-twin analysis with dizygotic (DZ) twin pairs discordant for GERD, and 3) within-pair co-twin analysis with monozygotic (MZ) twin pairs discordant for GERD. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated and adjusted for established risk factors for GERD, i.e. sex, age, body mass index (BMI), tobacco smoking, and educational level. Results A dose-response association was identified between increasing levels of sleep problems and GERD in the external control analysis. Individuals who often experienced sleep problems had a two-fold increased occurrence of GERD compared to those who seldom had sleep problems (OR 2.0, 95% CI 1.8–2.4). The corresponding association was of similar strength in the co-twin analysis including 356 DZ pairs (OR 2.2, 95% CI 1.6–3.4), and in the co-twin analysis including 210 MZ pairs (OR 1.5, 95% CI 0.9–2.7). Conclusion A dose-dependent association between sleep problems and GERD remains after taking heredity and other known risk factors for GERD into account. PMID:23119069

Does chess instruction improve mathematical problem-solving ability? Two experimental studies with an active control group.

PubMed

Sala, Giovanni; Gobet, Fernand

2017-12-01

It has been proposed that playing chess enables children to improve their ability in mathematics. These claims have been recently evaluated in a meta-analysis (Sala & Gobet, 2016, Educational Research Review, 18, 46-57), which indicated a significant effect in favor of the groups playing chess. However, the meta-analysis also showed that most of the reviewed studies used a poor experimental design (in particular, they lacked an active control group). We ran two experiments that used a three-group design including both an active and a passive control group, with a focus on mathematical ability. In the first experiment (N = 233), a group of third and fourth graders was taught chess for 25 hours and tested on mathematical problem-solving tasks. Participants also filled in a questionnaire assessing their meta-cognitive ability for mathematics problems. The group playing chess was compared to an active control group (playing checkers) and a passive control group. The three groups showed no statistically significant difference in mathematical problem-solving or metacognitive abilities in the posttest. The second experiment (N = 52) broadly used the same design, but the Oriental game of Go replaced checkers in the active control group. While the chess-treated group and the passive control group slightly outperformed the active control group with mathematical problem solving, the differences were not statistically significant. No differences were found with respect to metacognitive ability. These results suggest that the effects (if any) of chess instruction, when rigorously tested, are modest and that such interventions should not replace the traditional curriculum in mathematics.

Structural language, pragmatic communication, behavior, and social competence in children adopted internationally: A pilot study.

PubMed

Petranovich, Christine L; Walz, Nicolay Chertkoff; Staat, Mary Allen; Chiu, Chung-Yiu Peter; Wade, Shari L

2017-01-01

The objectives of this study were to examine the association of structural language and pragmatic communication with behavior problems and social competence in girls adopted internationally. Participants included girls between 6-12 years of age who were internationally adopted from China (n = 32) and Eastern-Europe (n = 25) and a control group of never-adopted girls (n = 25). Children completed the Wechsler Abbreviated Scale of Intelligence. Parents completed the Child Communication Checklist- second edition, the Child Behavior Checklist, and the Home and Community Social Behavior Scales. Compared to the controls, parents in the Eastern European group reported more problems with social competence, externalizing behaviors, structural language, and pragmatic communication. The Chinese group evidenced more internalizing problems. Using generalized linear regression, interaction terms were examined to determine if the associations of pragmatic communication and structural language with behavior problems and social competence varied across groups. Controlling for general intellectual functioning, poorer pragmatic communication was associated with more externalizing problems and poorer social competence. In the Chinese group, poorer pragmatic communication was associated with more internalizing problems. Post-adoption weaknesses in pragmatic communication are associated with behavior problems and social competence. Internationally adopted children may benefit from interventions that target pragmatic communication.

A Randomized Trial of the Effects of Schema-Based Instruction on Proportional Problem-Solving for Students With Mathematics Problem-Solving Difficulties.

PubMed

Jitendra, Asha K; Harwell, Michael R; Dupuis, Danielle N; Karl, Stacy R

This article reports results from a study investigating the efficacy of a proportional problem-solving intervention, schema-based instruction (SBI), in seventh grade. Participants included 806 students with mathematical difficulties in problem solving (MD-PS) from an initial pool of 1,999 seventh grade students in a larger study. Teachers and their students in the larger study were randomly assigned to an SBI or control condition and teachers in both conditions then provided instruction on the topics of ratio, proportion, and percent. We found that students with MD-PS in SBI classrooms scored on average higher than their counterparts in control classrooms on a posttest and delayed posttest administered 9 weeks later. Given students' difficulties with proportional problem-solving and the consequences of these difficulties, an important contribution of this research is the finding that when provided with appropriate instruction, students with MD-PS are capable of enhanced proportional problem-solving performance.

Variational Trajectory Optimization Tool Set: Technical description and user's manual

NASA Technical Reports Server (NTRS)

Bless, Robert R.; Queen, Eric M.; Cavanaugh, Michael D.; Wetzel, Todd A.; Moerder, Daniel D.

1993-01-01

The algorithms that comprise the Variational Trajectory Optimization Tool Set (VTOTS) package are briefly described. The VTOTS is a software package for solving nonlinear constrained optimal control problems from a wide range of engineering and scientific disciplines. The VTOTS package was specifically designed to minimize the amount of user programming; in fact, for problems that may be expressed in terms of analytical functions, the user needs only to define the problem in terms of symbolic variables. This version of the VTOTS does not support tabular data; thus, problems must be expressed in terms of analytical functions. The VTOTS package consists of two methods for solving nonlinear optimal control problems: a time-domain finite-element algorithm and a multiple shooting algorithm. These two algorithms, under the VTOTS package, may be run independently or jointly. The finite-element algorithm generates approximate solutions, whereas the shooting algorithm provides a more accurate solution to the optimization problem. A user's manual, some examples with results, and a brief description of the individual subroutines are included.

Characteristics of the personal and environmental components of person-environment fit in very old age: a comparison between people with self-reported Parkinson's disease and matched controls.

PubMed

Slaug, Björn; Nilsson, Maria H; Iwarsson, Susanne

2013-12-01

To investigate differences and similarities in person-environment (P-E) fit problems between very old people with self-reported Parkinson's disease (PD) and matched controls. Data collected for the cross-national ENABLE-AGE Survey Study were used to identify people with self-reported PD (n = 20), and to select three matched controls per individual (n = 60). The matching criteria were age (mean = 82 years), sex, country, and type of housing. The data analysis targeted P-E fit (i.e. accessibility) problems, including studying the personal and environmental components separately. The personal component was analyzed in terms of functional limitations, and the environmental component in terms of physical environmental barriers. In comparison to the matched controls, the participants with PD had more functional limitations, used more mobility devices and were subjected to more P-E fit problems, though the number of environmental barriers did not differ from the controls. In the PD sample, P-E fit problems were significantly stronger associated with poor balance and incoordination, and the environmental barriers that generated the most severe P-E fit problems were more often located to the exterior surroundings of the housing compared to the controls. The novel contribution of this explorative study is the demonstration of the type of knowledge that can be generated by unfolding and comparing the composition of P-E fit (accessibility) problems among people with self-reported PD as compared with matched controls. The knowledge thereby generated can be used to develop more targeted rehabilitation approaches, efficient housing adaptation services and societal planning for people with neurodegenerative disorders.

Baby Business: a randomised controlled trial of a universal parenting program that aims to prevent early infant sleep and cry problems and associated parental depression

PubMed Central

2012-01-01

Background Infant crying and sleep problems (e.g. frequent night waking, difficulties settling to sleep) each affect up to 30% of infants and often co-exist. They are costly to manage and associated with adverse outcomes including postnatal depression symptoms, early weaning from breast milk, and later child behaviour problems. Preventing such problems could improve these adverse outcomes and reduce costs to families and the health care system. Anticipatory guidance-i.e. providing parents with information about normal infant sleep and cry patterns, ways to encourage self-settling in infants, and ways to develop feeding and settling routines before the onset of problems-could prevent such problems. This paper outlines the protocol for our study which aims to test an anticipatory guidance approach. Methods/Design 750 families from four Local Government Areas in Melbourne, Australia have been randomised to receive the Baby Business program (intervention group) or usual care (control group) offered by health services. The Baby Business program provides parents with information about infant sleep and crying via a DVD and booklet (mailed soon after birth), telephone consultation (at infant age 6-8 weeks) and parent group session (at infant age 12 weeks). All English speaking parents of healthy newborn infants born at > 32 weeks gestation and referred by their maternal and child health nurse at their first post partum home visit (day 7-10 postpartum), are eligible. The primary outcome is parent report of infant night time sleep as a problem at four months of age and secondary outcomes include parent report of infant daytime sleep or crying as a problem, mean duration of infant sleep and crying/24 hours, parental depression symptoms, parent sleep quality and quantity and health service use. Data will be collected at two weeks (baseline), four months and six months of age. An economic evaluation using a cost-consequences approach will, from a societal perspective, compare costs and health outcomes between the intervention and control groups. Discussion To our knowledge this is the first randomised controlled trial of a program which aims to prevent both infant sleeping and crying problems and associated postnatal depression symptoms. If effective, it could offer an important public health prevention approach to these common, distressing problems. Trial registration number ISRCTN: ISRCTN63834603 PMID:22309617

Baby Business: a randomised controlled trial of a universal parenting program that aims to prevent early infant sleep and cry problems and associated parental depression.

PubMed

Cook, Fallon; Bayer, Jordana; Le, Ha N D; Mensah, Fiona; Cann, Warren; Hiscock, Harriet

2012-02-06

Infant crying and sleep problems (e.g. frequent night waking, difficulties settling to sleep) each affect up to 30% of infants and often co-exist. They are costly to manage and associated with adverse outcomes including postnatal depression symptoms, early weaning from breast milk, and later child behaviour problems. Preventing such problems could improve these adverse outcomes and reduce costs to families and the health care system. Anticipatory guidance-i.e. providing parents with information about normal infant sleep and cry patterns, ways to encourage self-settling in infants, and ways to develop feeding and settling routines before the onset of problems-could prevent such problems. This paper outlines the protocol for our study which aims to test an anticipatory guidance approach. 750 families from four Local Government Areas in Melbourne, Australia have been randomised to receive the Baby Business program (intervention group) or usual care (control group) offered by health services. The Baby Business program provides parents with information about infant sleep and crying via a DVD and booklet (mailed soon after birth), telephone consultation (at infant age 6-8 weeks) and parent group session (at infant age 12 weeks). All English speaking parents of healthy newborn infants born at > 32 weeks gestation and referred by their maternal and child health nurse at their first post partum home visit (day 7-10 postpartum), are eligible. The primary outcome is parent report of infant night time sleep as a problem at four months of age and secondary outcomes include parent report of infant daytime sleep or crying as a problem, mean duration of infant sleep and crying/24 hours, parental depression symptoms, parent sleep quality and quantity and health service use. Data will be collected at two weeks (baseline), four months and six months of age. An economic evaluation using a cost-consequences approach will, from a societal perspective, compare costs and health outcomes between the intervention and control groups. To our knowledge this is the first randomised controlled trial of a program which aims to prevent both infant sleeping and crying problems and associated postnatal depression symptoms. If effective, it could offer an important public health prevention approach to these common, distressing problems.

Drug-related problems and pharmacist interventions in a cohort of patients with asthma and chronic obstructive pulmonary disease.

PubMed

Apikoglu-Rabus, Sule; Yesilyaprak, Gozde; Izzettin, Fikret Vehbi

2016-11-01

Asthma and chronic obstructive pulmonary disease are preventable and treatable chronic airway diseases with high incidence and prevalence. Pharmacists and clinical pharmacy based pharmaceutical care services have positive impact on therapy outcomes. The aim of this study is to describe drug related problems in a cohort of patients with asthma and chronic obstructive pulmonary disease and to assess interventions provided by the pharmacist to address these problems in a community pharmacy. Study population consisted of patients with asthma and chronic obstructive pulmonary disease older than 18 years who visited the study pharmacy during the pre-determined six-month period. The patients whose disease control states were "not fully controlled" were included in our study for further steps. On the first interview, present and potential drug related problems were addressed, interventions were provided. Follow-up interviews were held one month and two months later than the first interview. For the 44 patients with asthma, 59 drug-related problems and 134 causes for these problems were identified. Eighty-four interventions were made to resolve the problems; and 54.2% of the problems were resolved. For the 37 patients with chronic obstructive pulmonary disease, 60 drug-related problems and 128 causes for these problems were identified. Ninety-five interventions were made to resolve the problems; and 63.3% of the problems were resolved. Pharmacists taking part in therapy and management of asthma and chronic obstructive pulmonary disease can help patients be more educated about their disease and medications; and improve disease control and therapy outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Fragrant Chemist

ERIC Educational Resources Information Center

Ward, P.

1973-01-01

The chemist plays an important role in perfumery. There are scientific problems involved in relating odour to structure, including analysis of essential oils, quality control, and synthetic chemistry. (DF)

Legendre spectral-collocation method for solving some types of fractional optimal control problems

PubMed Central

Sweilam, Nasser H.; Al-Ajami, Tamer M.

2014-01-01

In this paper, the Legendre spectral-collocation method was applied to obtain approximate solutions for some types of fractional optimal control problems (FOCPs). The fractional derivative was described in the Caputo sense. Two different approaches were presented, in the first approach, necessary optimality conditions in terms of the associated Hamiltonian were approximated. In the second approach, the state equation was discretized first using the trapezoidal rule for the numerical integration followed by the Rayleigh–Ritz method to evaluate both the state and control variables. Illustrative examples were included to demonstrate the validity and applicability of the proposed techniques. PMID:26257937

Extending religion-health research to secular minorities: issues and concerns.

PubMed

Hwang, Karen; Hammer, Joseph H; Cragun, Ryan T

2011-09-01

Claims about religion's beneficial effects on physical and psychological health have received substantial attention in popular media, but empirical support for these claims is mixed. Many of these claims are tenuous because they fail to address basic methodological issues relating to construct validity, sampling methods or analytical problems. A more conceptual problem has to do with the near universal lack of atheist control samples. While many studies include samples of individuals classified as "low spirituality" or religious "nones", these groups are heterogeneous and contain only a fraction of members who would be considered truly secular. We illustrate the importance of including an atheist control group whenever possible in the religiosity/spirituality and health research and discuss areas for further investigation.

Policy options for prevention: the case of alcohol.

PubMed

Toomey, T L; Wagenaar, A C

1999-01-01

Reducing the availability of alcohol through alcohol control policies such as excise taxes and the minimum legal drinking age has been effective in reducing a wide range of alcohol-related problems, including traffic crashes, liver cirrhosis, and violence. Alcohol control policies may be classified into two overlapping categories--public and institutional policies. Some policies such as alcohol server training may be either mandated by governmental jurisdictions or voluntarily adopted by individual institutions, which include alcohol retail establishments, other businesses, worksites, schools, colleges/universities, law enforcement agencies, religious institutions, insurance agencies, and alcohol producers. Public policies may be mandated by national, state/provincial, or local governments to regulate where, when, and how alcohol is sold and consumed. This paper describes the wide array of public and institutional policies available to reduce alcohol-related problems. Summaries of research evaluating specific alcohol control policies are provided when available.

Pareto-front shape in multiobservable quantum control

NASA Astrophysics Data System (ADS)

Sun, Qiuyang; Wu, Re-Bing; Rabitz, Herschel

2017-03-01

Many scenarios in the sciences and engineering require simultaneous optimization of multiple objective functions, which are usually conflicting or competing. In such problems the Pareto front, where none of the individual objectives can be further improved without degrading some others, shows the tradeoff relations between the competing objectives. This paper analyzes the Pareto-front shape for the problem of quantum multiobservable control, i.e., optimizing the expectation values of multiple observables in the same quantum system. Analytic and numerical results demonstrate that with two commuting observables the Pareto front is a convex polygon consisting of flat segments only, while with noncommuting observables the Pareto front includes convexly curved segments. We also assess the capability of a weighted-sum method to continuously capture the points along the Pareto front. Illustrative examples with realistic physical conditions are presented, including NMR control experiments on a 1H-13C two-spin system with two commuting or noncommuting observables.

In-flight simulation studies at the NASA Dryden Flight Research Facility

NASA Technical Reports Server (NTRS)

Shafer, Mary F.

1992-01-01

Since the late 1950's, the National Aeronautics and Space Administration's Dryden Flight Research Facility has found in-flight simulation to be an invaluable tool. In-flight simulation has been used to address a wide variety of flying qualities questions, including low-lift-to-drag ratio approach characteristics for vehicles like the X-15, the lifting bodies, and the Space Shuttle; the effects of time delays on controllability of aircraft with digital flight-control systems, the causes and cures of pilot-induced oscillation in a variety of aircraft, and flight-control systems for such diverse aircraft as the X-15 and the X-29. In-flight simulation has also been used to anticipate problems and to avoid them and to solve problems once they appear. Presented here is an account of the in-flight simulation at the Dryden Flight Research Facility and some discussion. An extensive bibliography is included.

In-flight simulation studies at the NASA Dryden Flight Research Facility

NASA Technical Reports Server (NTRS)

Shafer, Mary F.

1994-01-01

Since the late 1950's the National Aeronautics and Space Administration's Dryden Flight Research Facility has found in-flight simulation to be an invaluable tool. In-flight simulation has been used to address a wide variety of flying qualities questions, including low lift-to-drag ratio approach characteristics for vehicles like the X-15, the lifting bodies, and the space shuttle; the effects of time delays on controllability of aircraft with digital flight control systems; the causes and cures of pilot-induced oscillation in a variety of aircraft; and flight control systems for such diverse aircraft as the X-15 and the X-29. In-flight simulation has also been used to anticipate problems, avoid them, and solve problems once they appear. This paper presents an account of the in-flight simulation at the Dryden Flight Research Facility and some discussion. An extensive bibliography is included.

A multimodal interface to resolve the Midas-Touch problem in gaze controlled wheelchair.

PubMed

Meena, Yogesh Kumar; Cecotti, Hubert; Wong-Lin, KongFatt; Prasad, Girijesh

2017-07-01

Human-computer interaction (HCI) research has been playing an essential role in the field of rehabilitation. The usability of the gaze controlled powered wheelchair is limited due to Midas-Touch problem. In this work, we propose a multimodal graphical user interface (GUI) to control a powered wheelchair that aims to help upper-limb mobility impaired people in daily living activities. The GUI was designed to include a portable and low-cost eye-tracker and a soft-switch wherein the wheelchair can be controlled in three different ways: 1) with a touchpad 2) with an eye-tracker only, and 3) eye-tracker with soft-switch. The interface includes nine different commands (eight directions and stop) and integrated within a powered wheelchair system. We evaluated the performance of the multimodal interface in terms of lap-completion time, the number of commands, and the information transfer rate (ITR) with eight healthy participants. The analysis of the results showed that the eye-tracker with soft-switch provides superior performance with an ITR of 37.77 bits/min among the three different conditions (p<;0.05). Thus, the proposed system provides an effective and economical solution to the Midas-Touch problem and extended usability for the large population of disabled users.

Effect of genes, environment, and lifetime co-occurring disorders on health-related quality of life in problem and pathological gamblers.

PubMed

Scherrer, Jeffrey F; Xian, Hong; Shah, Kamini R; Volberg, Rachel; Slutske, Wendy; Eisen, Seth A

2005-06-01

Problem and pathological gambling are associated with many impairments in quality of life, including financial, family, legal, and social problems. Gambling disorders commonly co-occur with other psychiatric disorders, such as alcoholism and depression. Although these consequences and correlates have been reported, little is known about the health-related functional impairment associated with gambling. To model differences in the health-related quality of life (HRQoL) among non-problem gamblers, problem gamblers, and pathological gamblers after controlling for lifetime co-occurring substance use disorders, psychiatric disorders, sociodemographics, and genetic and family environmental influences. Cohort and co-twin studies. Nationally distributed community sample. Male twin members of the Vietnam Era Twin Registry: 53 pathological gamblers, 270 subclinical problem gamblers, and 1346 non-problem gamblers (controls). We obtained HRQoL data, via the 8-Item Short-Form Health Survey, from all participants. Data from a subset of twin pairs discordant for gambling behavior was used to control for genetic and family environmental effects on HRQoL and problem gambling. Main Outcome Measure Health-related quality of life. Results from adjusted logistic regression analyses suggest little difference across groups in the physical domains of the health survey; however, for each mental health domain, pathological gamblers had lower HRQoL scores than problem gamblers (P<.05), who in turn had lower scores than non-problem gamblers (P<.05). After controlling for genes and family environment, no significant differences existed between the non-problem gambling twins and their problem or pathological gambling brothers, but adjusted co-twin analyses resulted in statistically significant differences in 4 of 8 subscales. Pathological and problem gambling are associated with significant decrements in HRQoL. This association is partly explained by genetic and family environmental effects and by lifetime co-occurring substance use disorders. Implications for clinicians, health care utilization, and public health issues are discussed.

Combined monitoring, decision and control model for the human operator in a command and control desk

NASA Technical Reports Server (NTRS)

Muralidharan, R.; Baron, S.

1978-01-01

A report is given on the ongoing efforts to mode the human operator in the context of the task during the enroute/return phases in the ground based control of multiple flights of remotely piloted vehicles (RPV). The approach employed here uses models that have their analytical bases in control theory and in statistical estimation and decision theory. In particular, it draws heavily on the modes and the concepts of the optimal control model (OCM) of the human operator. The OCM is being extended into a combined monitoring, decision, and control model (DEMON) of the human operator by infusing decision theoretic notions that make it suitable for application to problems in which human control actions are infrequent and in which monitoring and decision-making are the operator's main activities. Some results obtained with a specialized version of DEMON for the RPV control problem are included.

An investigation into the design and performance of an automatic shape control system for a Sendzimir cold rolling mill

NASA Astrophysics Data System (ADS)

Dutton, Kenneth

Shape (or flatness) control for rolled steel strip is becoming increasingly important as customer requirements become more stringent. Automatic shape control is now more or less mandatory on all new four-high cold mills, but no comprehensive scheme yet exists on a Sendzimir mill. This is due to the complexity of the control system design on such a mill, where many more degrees of freedom for control exist than is the case with the four-high mills.The objective of the current work is to develop, from first principles, such a system; including automatic control of the As-U-Roll and first intermediate roll actuators in response to the measured strip shape. This thesis concerns itself primarily with the As-U-Roll control system. The material presented is extremely wide-ranging. Areas covered include the development of original static and dynamic mathematical models of the mill systems, and testing of the plant by data-logging to tune these models. A basic control system philosophy proposed by other workers is modified and developed to suit the practical system requirements and the data provided by the models. The control strategy is tested by comprehensive multivariable simulation studies. Finally, details are given of the practical problems faced when installing the system on the plant. These include problems of manual control inter-action bumpless transfer and integral desaturation.At the time of presentation of the thesis, system commissioning is still in progress and production results are therefore not yet available. Nevertheless, the simulation studies predict a successful outcome, although performance is expected to be limited until the first intermediate roll actuators are eventually included in the scheme also.

Three Randomized Controlled Trials of Early Long-Chain Polyunsaturated Fatty Acid Supplementation on Means-End Problem Solving in 9-Month-Olds

ERIC Educational Resources Information Center

Drover, James; Hoffman, Dennis R.; Castaneda, Yolanda S.; Morale, Sarah E.; Birch, Eileen E.

2009-01-01

This study examines whether feeding infants formula supplemented with long-chain polyunsaturated fatty acids (LCPUFA) improves cognitive function of 9-month-olds. Participants included 229 infants from 3 randomized controlled trials. Children received either formula supplemented with docosahexaenoic acid and arachidonic acid, or a control formula…

Apollo experience report. Guidance and control systems: Command and service module stabilization and control system

NASA Technical Reports Server (NTRS)

Littleton, O. P.

1974-01-01

The concepts, design, development, testing, and flight results of the command and service module stabilization and control system are discussed. The period of time covered was from November 1961 to December 1972. Also included are a functional description of the system, a discussion of the major problems, and recommendations for future programs.

The Control of Food among Schoolchildren Who Have Been Racially and Economically Marginalized across the Cityscape

ERIC Educational Resources Information Center

Hall, Julia

2014-01-01

This analysis involves an investigation of the corporate control of food in relation to low income and culturally dominated schoolchildren in cities. This includes an exploration of the problem as expressed globally and historically in relation to transnational policy networks. Since corporate growth always necessitates controlling the direction…

On the theory of singular optimal controls in dynamic systems with control delay

NASA Astrophysics Data System (ADS)

Mardanov, M. J.; Melikov, T. K.

2017-05-01

An optimal control problem with a control delay is considered, and a more broad class of singular (in classical sense) controls is investigated. Various sequences of necessary conditions for the optimality of singular controls in recurrent form are obtained. These optimality conditions include analogues of the Kelley, Kopp-Moyer, R. Gabasov, and equality-type conditions. In the proof of the main results, the variation of the control is defined using Legendre polynomials.

14 CFR Appendix K to Part 25 - Extended Operations (ETOPS)

Code of Federal Regulations, 2011 CFR

2011-01-01

... Appendix C of this part with a liquid water content factor of 1.0. (iii) Ice accumulated during approach... engine control or the desired thrust or power level was not achieved, including engine flameouts. Planned... involved. A relevant problem is a problem with an ETOPS group 1 significant system that has or could result...

Enhancing Social Inclusion of Children with Externalizing Problems through Classroom Seating Arrangements: A Randomized Controlled Trial

ERIC Educational Resources Information Center

van den Berg, Y. H. M.; Stoltz, S.

2018-01-01

Inclusive education has brought new challenges for teachers, including the search for a suitable place in the classroom for children with externalizing problems. In the current study, we examined whether a careful rearrangement of the classroom seats could promote social acceptance and more prosocial behaviors for children with externalizing…

Do We Really Have an Internet Problem? Statistics, Credibility and Issues Concerning Public Internet Access in Academic Libraries.

ERIC Educational Resources Information Center

Cubbage, Charlotte

2002-01-01

Discusses problems with patron Internet access in academic libraries and describes a study conducted at Northwestern University (Illinois) that used Internet tracking software to assess user Internet behavior. Topics include Internet use policies; pornography; and loss of control over library services and information content that is provided. (LRW)

Preventing Alcohol-Related Problems in the US through Policy: Media Campaigns, Regulatory Approaches and Environmental Interventions.

ERIC Educational Resources Information Center

Giesbrecht, Norman; Greenfield, Thomas K.

2003-01-01

Provides an overview of research focusing on several general strategies for reducing drinking-related problems, including controls on alcohol advertising and counter advertising; laws and regulations pertaining to minimum legal drinking age, and service to minors and drinking and driving. Concludes with a commentary on the potential effectiveness…

A method of measuring increase in soil depth and water-storage capacity due to forest management

Treesearch

George R., Jr. Trimble

1952-01-01

Conservationists, engineers, and others who deal with water problems have become more and more concerned in recent years with increasing the storage of water in the ground. Their concern has centered around problems of flood control and storage of water for later use by plants or animals, including man.

Rotordynamic Instability Problems in High-Performance Turbomachinery

NASA Technical Reports Server (NTRS)

1980-01-01

Diagnostic and remedial methods concerning rotordynamic instability problems in high performance turbomachinery are discussed. Instabilities due to seal forces and work-fluid forces are identified along with those induced by rotor bearing systems. Several methods of rotordynamic control are described including active feedback methods, the use of elastometric elements, and the use of hydrodynamic journal bearings and supports.

Development of a Comprehensive Digital Avionics Curriculum for the Aeronautical Engineer

DTIC Science & Technology

2006-03-01

able to analyze and design aircraft and missile guidance and control systems, including feedback stabilization schemes and stochastic processes, using ...Uncertainty modeling for robust control; Robust closed-loop stability and performance; Robust H- infinity control; Robustness check using mu-analysis...Controlled feedback (reduces noise) 3. Statistical group response (reduce pressure toward conformity) When used as a tool to study a complex problem

Substance Abuse and Counseling: An Epilogue.

ERIC Educational Resources Information Center

Sales, Amos

This chapter discusses current issues and future perspectives in relation to substance abuse counseling. Current issues include: abstinence versus controlled use; coercive versus voluntary treatment; and career development and counseling with clients with substance abuse problems. Future perspectives include: the impact of managed care; the…

Accelerated long-term forgetting and behavioural difficulties in children with epilepsy.

PubMed

Gascoigne, Michael B; Smith, Mary Lou; Barton, Belinda; Webster, Richard; Gill, Deepak; Lah, Suncica

2018-03-30

Patients with epilepsy have been shown to exhibit a range of memory deficits, including the rapid forgetting of newly-learned material over long, but not short, delays (termed accelerated long-term forgetting; ALF). Behavioural problems, such as mood disorders and social difficulties, are also overrepresented among children with epilepsy, when compared to patients with other chronic diseases and the general population. We investigated whether ALF was associated with behavioural or psychosocial deficits in children with epilepsy. Patients with either idiopathic generalised epilepsy (IGE; n = 20) or temporal lobe epilepsy (TLE; n = 23) and healthy controls (n = 53) of comparable age, sex, and socioeconomic status completed a battery of neuropsychological tests, including a list-learning task that required recall after short (30-min) and long (7-day) delays. Parents or guardians of all participants also completed the Child Behavior Checklist (CBCL). Compared to control participants, patients with IGE and TLE had higher scores on all but one of the indices of behavioural problems. When patients with IGE and TLE were merged into a single group, they were found to have negative correlations between 7-day recall and internalising, social and total problem behaviour domains, where poorer 7-day recall was associated with behavioural problems of greater severity. These findings suggest that impaired episodic recall is associated with behavioural deficits, including social problems, which are routinely observed in patients with epilepsy. Copyright © 2018 Elsevier Ltd. All rights reserved.

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. V.; Yerazunis, S. W.

1973-01-01

Problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars are reported. Problem areas include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis, terrain modeling and path selection; and chemical analysis of specimens. These tasks are summarized: vehicle model design, mathematical model of vehicle dynamics, experimental vehicle dynamics, obstacle negotiation, electrochemical controls, remote control, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, and chromatograph model evaluation and improvement.

The social problem-solving abilities of people with borderline personality disorder.

PubMed

Bray, Stephanie; Barrowclough, Christine; Lobban, Fiona

2007-06-01

Interventions for people suffering from borderline personality disorder (BPD), such as dialectical behaviour therapy, often include a problem-solving component. However, there is an absence of published studies examining the problem-solving abilities of this client group. In this study, the social problem-solving (SPS) abilities of three groups of participants were assessed: a BPD group (n=25), a clinical control (CC) group (n=25) procedure and a non-clinical control (NCC) group (n=25). SPS ability was assessed using the means-end problem-solving (MEPS) procedure and the Social Problem-Solving Inventory-Revised (SPSI-R). The BPD group exhibited deficits in their SPS abilities, however the majority of these deficits were not specific to the BPD group but were also found in the CC group, indicating that a common factor between these two groups, such as negative affect, may account for these observed deficits. Specific SPS deficits were identified in the BPD group: they provided less specific solutions on the MEPS and reported higher levels of negative problem orientation and a more impulsive/carelessness style towards solving social problems. The results of this study provide empirical support for the use of problem-solving interventions with people suffering from BPD.

How do robots take two parts apart

NASA Technical Reports Server (NTRS)

Bajcsy, Ruzena K.; Tsikos, Constantine J.

1989-01-01

This research is a natural progression of efforts which begun with the introduction of a new research paradigm in machine perception, called Active Perception. There it was stated that Active Perception is a problem of intelligent control strategies applied to data acquisition processes which will depend on the current state of the data interpretation, including recognition. The disassembly/assembly problem is treated as an Active Perception problem, and a method for autonomous disassembly based on this framework is presented.

Skylab thruster attitude control system

NASA Technical Reports Server (NTRS)

Wilmer, G. E., Jr.

1974-01-01

Preflight activities and the Skylab mission support effort for the thruster attitude control system (TACS) are documented. The preflight activities include a description of problems and their solutions encountered in the development, qualification, and flight checkout test programs. Mission support effort is presented as it relates to system performance assessment, real-time problem solving, flight anomalies, and the daily system evaluation. Finally, the detailed flight evaluation is presented for each phase of the mission using system telemetry data. Data assert that the TACS met or exceeded design requirements and fulfilled its assigned mission objectives.

Cognitive Profiles of Mathematical Problem Solving Learning Disability for Different Definitions of Disability

PubMed Central

Tolar, Tammy D.; Fuchs, Lynn; Fletcher, Jack M.; Fuchs, Douglas; Hamlett, Carol L.

2014-01-01

Three cohorts of third-grade students (N = 813) were evaluated on achievement, cognitive abilities, and behavioral attention according to contrasting research traditions in defining math learning disability (LD) status: low achievement versus extremely low achievement and IQ-achievement discrepant versus strictly low-achieving LD. We use methods from these two traditions to form math problem solving LD groups. To evaluate group differences, we used MANOVA-based profile and canonical analyses to control for relations among the outcomes and regression to control for group definition variables. Results suggest that basic arithmetic is the key distinguishing characteristic that separates low-achieving problem solvers (including LD, regardless of definition) from typically achieving students. Word problem solving is the key distinguishing characteristic that separates IQ-achievement-discrepant from strictly low-achieving LD students, favoring the IQ-achievement-discrepant students. PMID:24939971

Biological control of soilborne diseases in organic potato production as affected by varying environmental conditions

USDA-ARS?s Scientific Manuscript database

Soilborne diseases are persistent problems in potato production and alternative management practices are needed, particularly in organic production, where control options are limited. Selected biocontrol organisms, including two naturally-occurring hypovirulent strains of Rhizoctonia solani (Rhs1a1 ...

40 CFR 35.143 - Allotment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ASSISTANCE Environmental Program Grants Air Pollution Control (section 105) § 35.143 Allotment. (a) The Administrator allots air pollution control funds under section 105 of the Clean Air Act based on a number of factors, including: (1) Population; (2) The extent of actual or potential air pollution problems; and (3...

40 CFR 35.143 - Allotment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ASSISTANCE Environmental Program Grants Air Pollution Control (section 105) § 35.143 Allotment. (a) The Administrator allots air pollution control funds under section 105 of the Clean Air Act based on a number of factors, including: (1) Population; (2) The extent of actual or potential air pollution problems; and (3...

Development of Semiochemical Based Control Programs for Arthropod Pests of Honeybees

USDA-ARS?s Scientific Manuscript database

In recent years the apiculture industry has experienced serious problems from serious invasions by exotic pests including Varroa destructor and the Small hive beetle, Aethina tumida. Control of these pests is difficult and problematic because Honey bees are extremely sensitive to pesticides and the...

Analysis of general aviation single-pilot IFR incident data obtained from the NASA Aviation Safety Reporting System

NASA Technical Reports Server (NTRS)

Bergeron, H. P.

1983-01-01

An analysis of incident data obtained from the NASA Aviation Safety Reporting System (ASRS) has been made to determine the problem areas in general aviation single-pilot IFR (SPIFR) operations. The Aviation Safety Reporting System data base is a compilation of voluntary reports of incidents from any person who has observed or been involved in an occurrence which was believed to have posed a threat to flight safety. This paper examines only those reported incidents specifically related to general aviation single-pilot IFR operations. The frequency of occurrence of factors related to the incidents was the criterion used to define significant problem areas and, hence, to suggest where research is needed. The data was cataloged into one of five major problem areas: (1) controller judgment and response problems, (2) pilot judgment and response problems, (3) air traffic control (ATC) intrafacility and interfacility conflicts, (4) ATC and pilot communication problems, and (5) IFR-VFR conflicts. In addition, several points common to all or most of the problems were observed and reported. These included human error, communications, procedures and rules, and work load.

Development of an hp-version finite element method for computational optimal control

NASA Technical Reports Server (NTRS)

Hodges, Dewey H.; Warner, Michael S.

1993-01-01

The purpose of this research effort is to develop a means to use, and to ultimately implement, hp-version finite elements in the numerical solution of optimal control problems. The hybrid MACSYMA/FORTRAN code GENCODE was developed which utilized h-version finite elements to successfully approximate solutions to a wide class of optimal control problems. In that code the means for improvement of the solution was the refinement of the time-discretization mesh. With the extension to hp-version finite elements, the degrees of freedom include both nodal values and extra interior values associated with the unknown states, co-states, and controls, the number of which depends on the order of the shape functions in each element.

Neural Networks for Flight Control

NASA Technical Reports Server (NTRS)

Jorgensen, Charles C.

1996-01-01

Neural networks are being developed at NASA Ames Research Center to permit real-time adaptive control of time varying nonlinear systems, enhance the fault-tolerance of mission hardware, and permit online system reconfiguration. In general, the problem of controlling time varying nonlinear systems with unknown structures has not been solved. Adaptive neural control techniques show considerable promise and are being applied to technical challenges including automated docking of spacecraft, dynamic balancing of the space station centrifuge, online reconfiguration of damaged aircraft, and reducing cost of new air and spacecraft designs. Our experiences have shown that neural network algorithms solved certain problems that conventional control methods have been unable to effectively address. These include damage mitigation in nonlinear reconfiguration flight control, early performance estimation of new aircraft designs, compensation for damaged planetary mission hardware by using redundant manipulator capability, and space sensor platform stabilization. This presentation explored these developments in the context of neural network control theory. The discussion began with an overview of why neural control has proven attractive for NASA application domains. The more important issues in control system development were then discussed with references to significant technical advances in the literature. Examples of how these methods have been applied were given, followed by projections of emerging application needs and directions.

Maximum likelihood identification and optimal input design for identifying aircraft stability and control derivatives

NASA Technical Reports Server (NTRS)

Stepner, D. E.; Mehra, R. K.

1973-01-01

A new method of extracting aircraft stability and control derivatives from flight test data is developed based on the maximum likelihood cirterion. It is shown that this new method is capable of processing data from both linear and nonlinear models, both with and without process noise and includes output error and equation error methods as special cases. The first application of this method to flight test data is reported for lateral maneuvers of the HL-10 and M2/F3 lifting bodies, including the extraction of stability and control derivatives in the presence of wind gusts. All the problems encountered in this identification study are discussed. Several different methods (including a priori weighting, parameter fixing and constrained parameter values) for dealing with identifiability and uniqueness problems are introduced and the results given. The method for the design of optimal inputs for identifying the parameters of linear dynamic systems is also given. The criterion used for the optimization is the sensitivity of the system output to the unknown parameters. Several simple examples are first given and then the results of an extensive stability and control dervative identification simulation for a C-8 aircraft are detailed.

Pelvic Floor Disorders

MedlinePlus

... called urinary incontinence , can occur in women or men when the bladder falls from its proper place. Other symptoms include a sudden, strong urge to urinate. Bowel control problems. The leaking ...

Attitudes to body weight, weight gain and eating behavior in pregnancy.

PubMed

Abraham, S; King, W; Llewellyn-Jones, D

1994-12-01

The eating behavior and attitudes to body weight of 100 healthy women were studied 3 days after the birth of their first child. During pregnancy women 'watch their weight' and use a range of methods of weight control which include cigarette smoking and inducing vomiting. During pregnancy 41 women reported weight control problems and 20 women considered their weight and eating problems to be greater than at any previous time. Picking was the most common unwanted behavior. Binge eating was experienced by 44 women, nine of whom reported it to be a 'severe' problem. Although women were ambivalent about being weighed at each antenatal visit, 81 recommended weighing once each month. The women held differing opinions on the effects of breastfeeding on body weight and on the need for nutritional supplements during pregnancy. Women reporting 'disordered eating' were more likely to have antenatal complications and give birth to low birthweight babies. The results suggest good obstetric care should include a history of the woman's eating behavior and body weight.

Telephone Counseling to Implement Best Parenting Practices to Prevent Adolescent Problem Behaviors

PubMed Central

Pierce, John P.; James, Lisa E.; Messer, Karen; Myers, Mark G.; Williams, Rebecca E.; Trinidad, Dennis R.

2008-01-01

There is considerable suggestive evidence that parents can protect their adolescents from developing problem behaviors if they implement recommended best parenting practices. These include providing appropriate limits on adolescent free time, maintaining a close personal relationship with the adolescent, and negotiating and providing incentives for positive behavior patterns. However, retention of the study samples has limited conclusions that can be drawn from published studies. This randomized controlled trial recruited and randomized a national population sample of 1036 families to an intensive parenting intervention using telephone counseling or to a no-contact control group. At enrollment, eligible families had an eldest child between the ages of 10–13 years. The intervention included an initial training program using a self-help manual with telephone counselor support. Implementation of best parenting practices was encouraged using quarterly telephone contacts and a family management check-up questionnaire. A computer-assisted structured counseling protocol was used to aid parents who needed additional assistance to implement best practices. This, along with a centralized service, enabled implementation of quality control procedures. Assessment of problem behavior is undertaken with repeated telephone interviews of the target adolescents. The study is powered to test whether the intervention encouraging parents to maintain best parenting practices is associated with a reduction of 25% in the incidence of problem behaviors prior to age 18 years and will be tested through a maximum likelihood framework. PMID:17964223

Prospective Relations between Family Conflict and Adolescent Maladjustment: Security in the Family System as a Mediating Process

PubMed Central

Cummings, E. Mark; Koss, Kalsea J.; Davies, Patrick T.

2018-01-01

Conflict in specific family systems (e.g., interparental, parent-child) has been implicated in the development of a host of adjustment problems in adolescence, but little is known about the impact of family conflict involving multiple family systems. Furthermore, questions remain about the effects of family conflict on symptoms of specific disorders and adjustment problems and the processes mediating these effects. The present study prospectively examines the impact of family conflict and emotional security about the family system on adolescent symptoms of specific disorders and adjustment problems, including the development of symptoms of anxiety, depression, conduct problems, and peer problems. Security in the family system was examined as a mediator of these relations. Participants included 295 mother-father-adolescent families (149 girls) participating across three annual time points (grades 7–9). Including auto-regressive controls for initial levels of emotional insecurity and multiple adjustment problems (T1), higher-order emotional insecurity about the family system (T2) mediated relations between T1 family conflict and T3 peer problems, anxiety, and depressive symptoms. Further analyses supported specific patterns of emotional security/insecurity (i.e., security, disengagement, preoccupation) as mediators between family conflict and specific domains of adolescent adjustment. Family conflict was thus found to prospectively predict the development of symptoms of multiple specific adjustment problems, including symptoms of depression, anxiety, conduct problems, and peer problems, by elevating in in adolescent’s emotional insecurity about the family system. The clinical implications of these findings are considered. PMID:25131144

Perception of control, coping and psychological stress of infertile women undergoing IVF.

PubMed

Gourounti, Kleanthi; Anagnostopoulos, Fotios; Potamianos, Grigorios; Lykeridou, Katerina; Schmidt, Lone; Vaslamatzis, Grigorios

2012-06-01

The study aimed to examine: (i) the association between perception of infertility controllability and coping strategies; and (ii) the association between perception of infertility controllability and coping strategies to psychological distress, applying multivariate statistical techniques to control for the effects of demographic variables. This cross-sectional study included 137 women with fertility problems undergoing IVF in a public hospital. All participants completed questionnaires that measured fertility-related stress, state anxiety, depressive symptomatology, perception of control and coping strategies. Pearson's correlation coefficients were calculated between all study variables, followed by hierarchical multiple linear regression. Low perception of personal and treatment controllability was associated with frequent use of avoidance coping and high perception of treatment controllability was positively associated with problem-focused coping. Multivariate analysis showed that, when controlling for demographic factors, low perception of personal control and avoidance coping were positively associated with fertility-related stress and state anxiety, and problem-appraisal coping was negatively and significantly associated with fertility-related stress and depressive symptomatology scores. The findings of this study merit the understanding of the role of control perception and coping in psychological stress of infertile women to identify beforehand those women who might be at risk of experiencing high stress and in need of support. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Development and flight test experiences with a flight-crucial digital control system

NASA Technical Reports Server (NTRS)

Mackall, Dale A.

1988-01-01

Engineers and scientists in the advanced fighter technology integration (AFTI) F-16 program investigated the integration of emerging technologies into an advanced fighter aircraft. AFTI's three major technologies included: flight-crucial digital control, decoupled aircraft flight control, and integration of avionics, flight control, and pilot displays. In addition to investigating improvements in fighter performance, researchers studied the generic problems confronting the designers of highly integrated flight-crucial digital control. An overview is provided of both the advantages and problems of integration digital control systems. Also, an examination of the specification, design, qualification, and flight test life-cycle phase is provided. An overview is given of the fault-tolerant design, multimoded decoupled flight control laws, and integrated avionics design. The approach to qualifying the software and system designs is discussed, and the effects of design choices on system qualification are highlighted.

Macrofouling control in nuclear power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ekis, E.W. Jr.; Keoplin-Gall, S.M.; McCarthy, R.E.

1991-11-01

Macrofouling of cooling-water systems is one of the more significant and costly problems encountered in the nuclear power industry. Both marine and freshwater macroinvertebrates can be responsible for losses in plant availability because of plugged intakes and heat transfer equipment. There is a greater diversity of macrofouling organisms in marine waters than in fresh waters. Marine macrofouling organisms include barnacles, mollusks, bryozoans, and hydroids. Barnacles are crustaceans with feathery appendages, which allow them to attach to a variety of surfaces. They are a major cause of severe macrofouling because they can remain attached even after death. The major freshwater macrofoulingmore » organisms include the Asiatic Clam (Corbicula fluminea) and the newest freshwater macrofouler, the Zebra Mussel (Dreissena polymorpha). The introduction of the Zebra Mussel into the Great Lakes has created economic and ecological problems that will not easily be solved. The threat of intercontinental dispersal of the Zebra Mussel in America is serious. Research programs have been initiated around the country to develop control methods for this macrofouling problem. The various control methodologies can be classified in the following categories: biological, chemical, physical, and mechanical. Laboratory experiments were performed to evaluate the efficacy of Actibrom against mature Zebra Mussels.« less

Numerical Leak Detection in a Pipeline Network of Complex Structure with Unsteady Flow

NASA Astrophysics Data System (ADS)

Aida-zade, K. R.; Ashrafova, E. R.

2017-12-01

An inverse problem for a pipeline network of complex loopback structure is solved numerically. The problem is to determine the locations and amounts of leaks from unsteady flow characteristics measured at some pipeline points. The features of the problem include impulse functions involved in a system of hyperbolic differential equations, the absence of classical initial conditions, and boundary conditions specified as nonseparated relations between the states at the endpoints of adjacent pipeline segments. The problem is reduced to a parametric optimal control problem without initial conditions, but with nonseparated boundary conditions. The latter problem is solved by applying first-order optimization methods. Results of numerical experiments are presented.

Mental health and social competencies of 10- to 12-year-old children born at 23 to 25 weeks of gestation in the 1990s: a Swedish national prospective follow-up study.

PubMed

Farooqi, Aijaz; Hägglöf, Bruno; Sedin, Gunnar; Gothefors, Leif; Serenius, Fredrik

2007-07-01

We investigated a national cohort of extremely immature children with respect to behavioral and emotional problems and social competencies, from the perspectives of parents, teachers, and children themselves. We examined 11-year-old children who were born before 26 completed weeks of gestation in Sweden between 1990 and 1992. All had been evaluated at a corrected age of 36 months. At 11 years of age, 86 of 89 survivors were studied and compared with an equal number of control subjects, matched with respect to age and gender. Behavioral and emotional problems, social competencies, and adaptive functioning at school were evaluated with standardized, well-validated instruments, including parent and teacher report questionnaires and a child self-report, administered by mail. Compared with control subjects, parents of extremely immature children reported significantly more problems with internalizing behaviors (anxiety/depression, withdrawn, and somatic problems) and attention, thought, and social problems. Teachers reported a similar pattern. Reports from children showed a trend toward increased depression symptoms compared with control subjects. Multivariate analysis of covariance of parent-reported behavioral problems revealed no interactions, but significant main effects emerged for group status (extremely immature versus control), family function, social risk, and presence of a chronic medical condition, with all effect sizes being medium and accounting for 8% to 12% of the variance. Multivariate analysis of covariance of teacher-reported behavioral problems showed significant effects for group status and gender but not for the covariates mentioned above. According to the teachers' ratings, extremely immature children were less well adjusted to the school environment than were control subjects. However, a majority of extremely immature children (85%) were functioning in mainstream schools without major adjustment problems. Despite favorable outcomes for many children born at the limit of viability, these children are at risk for mental health problems, with poorer school results.

A Study of Fixed-Order Mixed Norm Designs for a Benchmark Problem in Structural Control

NASA Technical Reports Server (NTRS)

Whorton, Mark S.; Calise, Anthony J.; Hsu, C. C.

1998-01-01

This study investigates the use of H2, p-synthesis, and mixed H2/mu methods to construct full-order controllers and optimized controllers of fixed dimensions. The benchmark problem definition is first extended to include uncertainty within the controller bandwidth in the form of parametric uncertainty representative of uncertainty in the natural frequencies of the design model. The sensitivity of H2 design to unmodelled dynamics and parametric uncertainty is evaluated for a range of controller levels of authority. Next, mu-synthesis methods are applied to design full-order compensators that are robust to both unmodelled dynamics and to parametric uncertainty. Finally, a set of mixed H2/mu compensators are designed which are optimized for a fixed compensator dimension. These mixed norm designs recover the H, design performance levels while providing the same levels of robust stability as the u designs. It is shown that designing with the mixed norm approach permits higher levels of controller authority for which the H, designs are destabilizing. The benchmark problem is that of an active tendon system. The controller designs are all based on the use of acceleration feedback.

Model reduction in integrated controls-structures design

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.

1993-01-01

It is the objective of this paper to present a model reduction technique developed for the integrated controls-structures design of flexible structures. Integrated controls-structures design problems are typically posed as nonlinear mathematical programming problems, where the design variables consist of both structural and control parameters. In the solution process, both structural and control design variables are constantly changing; therefore, the dynamic characteristics of the structure are also changing. This presents a problem in obtaining a reduced-order model for active control design and analysis which will be valid for all design points within the design space. In other words, the frequency and number of the significant modes of the structure (modes that should be included) may vary considerably throughout the design process. This is also true as the locations and/or masses of the sensors and actuators change. Moreover, since the number of design evaluations in the integrated design process could easily run into thousands, any feasible order-reduction method should not require model reduction analysis at every design iteration. In this paper a novel and efficient technique for model reduction in the integrated controls-structures design process, which addresses these issues, is presented.

Power oscillation suppression by robust SMES in power system with large wind power penetration

NASA Astrophysics Data System (ADS)

Ngamroo, Issarachai; Cuk Supriyadi, A. N.; Dechanupaprittha, Sanchai; Mitani, Yasunori

2009-01-01

The large penetration of wind farm into interconnected power systems may cause the severe problem of tie-line power oscillations. To suppress power oscillations, the superconducting magnetic energy storage (SMES) which is able to control active and reactive powers simultaneously, can be applied. On the other hand, several generating and loading conditions, variation of system parameters, etc., cause uncertainties in the system. The SMES controller designed without considering system uncertainties may fail to suppress power oscillations. To enhance the robustness of SMES controller against system uncertainties, this paper proposes a robust control design of SMES by taking system uncertainties into account. The inverse additive perturbation is applied to represent the unstructured system uncertainties and included in power system modeling. The configuration of active and reactive power controllers is the first-order lead-lag compensator with single input feedback. To tune the controller parameters, the optimization problem is formulated based on the enhancement of robust stability margin. The particle swarm optimization is used to solve the problem and achieve the controller parameters. Simulation studies in the six-area interconnected power system with wind farms confirm the robustness of the proposed SMES under various operating conditions.

Power flow control using quadrature boosters

NASA Astrophysics Data System (ADS)

Sadanandan, Sandeep N.

A power system that can be controlled within security constraints would be an advantage to power planners and real-time operators. Controlling flows can lessen reliability issues such as thermal limit violations, power stability problems, and/or voltage stability conditions. Control of flows can also mitigate market issues by reducing congestion on some lines and rerouting power to less loaded lines or onto preferable paths. In the traditional control of power flows, phase shifters are often used. More advanced methods include using Flexible AC Transmission System (FACTS) Controllers. Some examples include Thyristor Controlled Series Capacitors, Synchronous Series Static Compensators, and Unified Power Flow Controllers. Quadrature Boosters (QBs) have similar structures to phase-shifters, but allow for higher voltage magnitude during real power flow control. In comparison with other FACTS controllers QBs are not as complex and not as expensive. The present study proposes to use QBs to control power flows on a power system. With the inclusion of QBs, real power flows can be controlled to desired scheduled values. In this thesis, the linearized power flow equations used for power flow analysis were modified for the control problem. This included modifying the Jacobian matrix, the power error vector, and calculating the voltage injected by the quadrature booster for the scheduled real power flow. Two scenarios were examined using the proposed power flow control method. First, the power flow in a line in a 5-bus system was modified with a QB using the method developed in this thesis. Simulation was carried out using Matlab. Second, the method was applied to a 30-bus system and then to a 118-bus system using several QBs. In all the cases, the calculated values of the QB voltages led to desired power flows in the designated line.

Perceived parental alcohol problems, internalizing problems and impaired parent - child relationships among 71 988 young people in Denmark.

PubMed

Pisinger, Veronica S C; Bloomfield, Kim; Tolstrup, Janne S

2016-11-01

To test the hypothesis that young people with perceived parental alcohol problems have poorer parent-child relationships and more emotional symptoms, low self-esteem, loneliness and depression than young people without perceived parental alcohol problems. Cross-sectional analysis using data from the Danish National Youth Study 2014, a web-based national survey. Denmark. A total of 71.988 high school and vocational school students (aged 12-25, nested in 119 schools and 3.186 school classes) recruited throughout 2014. Outcome variables included internalizing problems such as emotional symptoms, depression, self-esteem, loneliness and aspects of the parent-child relationship. The main predictor variable was perceived parental alcohol problems, including the severity of the perceived problems and living with a parent with alcohol problems. Control variables included age, sex, education, ethnicity, parents' separation and economic problems in the family. Boys and girls with perceived parental alcohol problems had statistically significant higher odds of reporting internalizing problems (e.g. frequent emotional symptoms: odds ratio (OR)= 1.58 for boys; 1.49 for girls) and poor parent-child relationships (e.g. lack of parental interest: OR = 1.92 for boys; 2.33 for girls) compared with young people without perceived parental alcohol problems. The associations were not significantly stronger for mother's alcohol problems or if the young person lived with the parent with perceived alcohol problems. Boys and girls in secondary education in Denmark who report perceived parental alcohol problems have significantly higher odds of internalizing problems and poorer parent-child relationships compared with young people without perceived parental alcohol problems. © 2016 Society for the Study of Addiction.

Hybrid near-optimal aeroassisted orbit transfer plane change trajectories

NASA Technical Reports Server (NTRS)

Calise, Anthony J.; Duckeman, Gregory A.

1994-01-01

In this paper, a hybrid methodology is used to determine optimal open loop controls for the atmospheric portion of the aeroassisted plane change problem. The method is hybrid in the sense that it combines the features of numerical collocation with the analytically tractable portions of the problem which result when the two-point boundary value problem is cast in the form of a regular perturbation problem. Various levels of approximation are introduced by eliminating particular collocation parameters and their effect upon problem complexity and required number of nodes is discussed. The results include plane changes of 10, 20, and 30 degrees for a given vehicle.

Vegetation management in Eucalyptus

Treesearch

Clyde L. Elmore

1983-01-01

Weeds and weed control are a major problem in the growth and management of Eucalyptus trees. Annual, biennial and perennial weed species are common in sites to be planted. These weeds should be controlled before planting. Preplant, preemergence and postemergence herbicides are discussed. Safe preemergence herbicides include oryzalin, napropamide, oxadiazon, linuron and...

Your World, My World.

ERIC Educational Resources Information Center

Environmental Protection Agency, Washington, DC.

Americans of all ages are concerned with the effects of pollution on the environment. This booklet is designed to explain to students the environmental problems related with pollution and its control. The role of the Environmental Protection Agency (EPA) in pollution control is defined and its goals explained. Topics of discussion include clean…

Behavioral Self-Control and Career Development.

ERIC Educational Resources Information Center

Thoresen, Carl E.; Ewart, Craig K.

A broader view of the career problem and the counselor's role through teaching clients behavioral self-control techniques is offered in this paper. Preliminary discussion includes a review of existing vocational theories and research, in particular, Holland's typology and Super's self-concept theory. It is concluded from these reviews that the…

Phase-change composites TES for nickel-hydrogen batteries

NASA Technical Reports Server (NTRS)

Knowles, Timothy R.; Meyer, Richard A.

1993-01-01

Viewgraphs of a discussion on phase-change composites thermal energy storage (TES) for nickel-hydrogen batteries are presented. Topics covered include Ni-H2 thermal control problems; passive thermal control with TES; phase-change composites (PCC); candidate materials; design options; fabrication and freeze-melt cycling; thermal modeling; system benefits; and applications.

Aggressive Behavior between Siblings and the Development of Externalizing Problems: Evidence from a Genetically Sensitive Study

PubMed Central

Natsuaki, Misaki N.; Ge, Xiaojia; Reiss, David; Neiderhiser, Jenae M.

2011-01-01

This study investigated the prospective links between sibling aggression and the development of externalizing problems using a multilevel modeling approach with a genetically sensitive design. The sample consisted of 780 adolescents (390 sibling pairs) who participated in two waves of the Nonshared Environment for Adolescent Development (NEAD) project. Sibling pairs with varying degree of genetic relatedness, including monozygotic twins, dizygotic twins, full siblings, half siblings, and genetically unrelated siblings, were included. The results showed that sibling aggression at Time 1 was significantly associated with the focal child’s externalizing problems at Time 2 after accounting for the intra-class correlations between siblings. Sibling aggression remained significant in predicting subsequent externalizing problems even after controlling for the levels of pre-existing externalizing problems and mothers’ punitive parenting. This pattern of results was fairly robust across models using different informants. The findings provide converging evidence for the unique contribution of sibling aggression in understanding changes in externalizing problems during adolescence. PMID:19586176

The dynamic of non-communicable disease control policy in Indonesia.

PubMed

Christiani, Yodi; Dugdale, Paul; Tavener, Meredith; Byles, Julie E

2017-05-01

Objective The aim of the present study was to examine non-communicable disease (NCD) policy formation and implementation in Indonesia. Methods Interviews were conducted with 13 Indonesian health policy workers. The processes and issues relating to NCD policy formation were mapped, exploring the interactions between policy makers, technical/implementation bodies, alliances across various levels and the mobilisation of non-policy actors. Results Problems in NCD policy formation include insufficient political interest in NCD control, disconnected policies and difficulty in multisectoral coordination. These problems are well illustrated in relation to tobacco control, but also apply to other control efforts. Nevertheless, participants were optimistic that there are plentiful opportunities for improving NCD control policies given growing global attention to NCD, increases in the national health budget and the growing body of Indonesia-relevant NCD-related research. Conclusion Indonesia's success in the creation and implementation of NCD policy will be dependent on high-level governmental leadership, including support from the President, the Health Minister and coordinating ministries. What is known about the topic? The burden of NCD in Indonesia has increased gradually. Nationally, NCD-related mortality accounted for 65% of deaths in 2010. Indonesia is also a country with the highest burden of tobacco smoking in the world. However, the government has not instituted sufficient policy action to tackle NCDs, including tobacco control. What does this paper add? This paper deepens our understanding of current NCD control policy formation in Indonesia, including the possible underlying reason why Indonesia has weak tobacco control policies. It describes the gaps in the current policies, the actors involved in policy formation, the challenges in policy formation and implementation and potential opportunities for improving NCD control. What are the implications for practitioners? An effective NCD control program requires strong collaboration, including between government and health professionals. Health professionals can actively engage in policy formation, for example through knowledge production.

Rapid Preliminary Design of Interplanetary Trajectories Using the Evolutionary Mission Trajectory Generator

NASA Technical Reports Server (NTRS)

Englander, Jacob

2016-01-01

Preliminary design of interplanetary missions is a highly complex process. The mission designer must choose discrete parameters such as the number of flybys, the bodies at which those flybys are performed, and in some cases the final destination. In addition, a time-history of control variables must be chosen that defines the trajectory. There are often many thousands, if not millions, of possible trajectories to be evaluated. This can be a very expensive process in terms of the number of human analyst hours required. An automated approach is therefore very desirable. This work presents such an approach by posing the mission design problem as a hybrid optimal control problem. The method is demonstrated on notional high-thrust chemical and low-thrust electric propulsion missions. In the low-thrust case, the hybrid optimal control problem is augmented to include systems design optimization.

A corrosion control manual for rail rapid transit

NASA Technical Reports Server (NTRS)

Gilbert, L. O.; Fitzgerald, J. F., II; Menke, J. T.

1982-01-01

In 1979, during the planning stage of the Metropolitan Dade County Transit System, the need was expressed for a corrosion control manual oriented to urban rapid transit system use. This manual responds to that need. The objective of the manual is to aid rail rapid transit agencies by providing practical solutions to selected corrosion problems. The scope of the manual encompasses corrosion problems of the facilities of rapid transit systems: structures and tracks, platforms and stations, power and signals, and cars. It also discusses stray electric current corrosion. Both design and maintenance solutions are provided for each problem. Also included are descriptions of the types of corrosion and their causes, descriptions of rapid transit properties, a list of corrosion control committees and NASA, DOD, and ASTM specifications and design criteria to which reference is made in the manual. A bibliography of papers and excerpts of reports and a glossary of frequency used terms are provided.

Differential Diagnosis of Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder by Means of Inhibitory Control and "Theory of Mind"

ERIC Educational Resources Information Center

Buhler, Eva; Bachmann, Christian; Goyert, Hannah; Heinzel-Gutenbrunner, Monika; Kamp-Becker, Inge

2011-01-01

Autism spectrum disorders (ASD) and attention deficit hyperactivity disorders (ADHD) are both associated with deficits in executive control and with problems in social contexts. This study analyses the variables inhibitory control and theory of mind (ToM), including a developmental aspect in the case of the latter, to differentiate between the…

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

1974-01-01

A number of problems related to the design, construction and evaluation of an autonomous roving planetary vehicle and its control and operating systems intended for an unmanned exploration of Mars are studied. Vehicle configuration, dynamics, control, systems and propulsion; systems analysis; terrain sensing and modeling and path selection; and chemical analysis of samples are included.

Control of functional differential equations with function space boundary conditions.

NASA Technical Reports Server (NTRS)

Banks, H. T.

1972-01-01

The results of various authors dealing with problems involving functional differential equations with terminal conditions in function space are reviewed. The review includes not only very recent results, but also some little known results of Soviet mathematicians prior to 1970. Particular attention is given to results concerning controllability, existence of optimal controls, and necessary and sufficient conditions for optimality.

Some logical functions of joint control.

PubMed Central

Lowenkron, B

1998-01-01

Constructing a behavioral account of the language-related performances that characterize responding to logical and symbolic relations between stimuli is commonly viewed as a problem for the area of stimulus control. In response to this problem, the notion of joint control is presented here, and its ability to provide an interpretative account of these kinds of performances is explored. Joint control occurs when the currently rehearsed topography of a verbal operant, as evoked by one stimulus, is simultaneously evoked by another stimulus. This event, the onset of joint stimulus control by two stimuli over a common response topography, then sets the occasion for a response appropriate to this special relation between the stimuli. Although the mechanism described is simple, it seems to have broad explanatory properties. In what follows, these properties are applied to provide a behavioral interpretation of two sorts of fundamental, putatively cognitive, performances: those based on logical relations and those based on semantic relations. The first includes responding to generalized conceptual relations such as identity, order, relative size, distance, and orientation. The second includes responding to relations usually ascribed to word meaning. These include relations between words and objects, the specification of objects by words, name-object bidirectionality, and the recognition of objects from their description. Finally, as a preview of some further possibilities, the role of joint control in goal-oriented behavior is considered briefly. PMID:9599452

Cognitive Behavioral Principles Within Group Mentoring: A Randomized Pilot Study

PubMed Central

JENT, JASON F.; NIEC, LARISSA N.

2010-01-01

This study evaluated the effectiveness of a group mentoring program that included components of empirically supported mentoring and cognitive behavioral techniques for children served at a community mental health center. Eighty-six 8- to 12-year-old children were randomly assigned to either group mentoring or a wait-list control group. Group mentoring significantly increased children’s reported social problem-solving skills and decreased parent-reported child externalizing and internalizing behavior problems after controlling for other concurrent mental health services. Attrition from the group mentoring program was notably low (7%) for children. The integration of a cognitive behavioral group mentoring program into children’s existing community mental health services may result in additional reductions in externalizing and internalizing behavior problems. PMID:20582243

Final Plenary Session Transcript

NASA Technical Reports Server (NTRS)

Gostelow, Paul

2010-01-01

Let s start with the report - as you know - when we are talking about flow control it is a multi-disciplinary type of work. So it involves many people and disciplines. This group first discussed the important issues associated with flow control. As you start doing flow control what are the issues to which you really have to start paying attention? That is the first part I am going to present. Then in the second part I will present some challenges - problems that we should really be looking at. So as far as the issues - if you want to control a flow, you really need to understand the flow physics, because anything that you do comes from the flow physics. The design of the controllers, your decisions on the actuators, sensors, reduced order modeling and all of that, would be helped if you understand flow physics. And you have to have a specific objective - what exactly are you controlling? Are you trying to reduce drag, eliminate separation, reduce noise, enhance mixing? So you have to have very specific control objectives. From all the talks we have seen here actuation is extremely important and it is very problem specific. It depends on what problem you are dealing with so you have to design and build actuators for that specific problem. Sensors obviously are very important, especially when you are dealing with feedback control. Consensus was that when you dealing with flow control, you must take an integrated approach; from the beginning you have to take into account every aspect of it and even maybe to modify your experiment, your geometry, to go along with the actuation, sensors and control models. Development of tools is very important in this multi-disciplinary problem. The tools include CFD, reduced order modeling, controller design, understanding and utilizing the instabilities of the flow, etc. So, in order to have success in flow control, we really need to develop these tools.

Effects of Aggression Replacement Training on Problem Solving, Anger and Aggressive Behaviour among Adolescents with Criminal Attempts in Turkey: A Quasi-Experimental Study.

PubMed

Kaya, Fadime; Buzlu, Sevim

2016-12-01

The research was conducted by a pretest and post-test conducted in a quasi-experimental design which aimed to determine effectiveness of Aggression Replacement Training (ART) on problem solving, anger and aggressive behaviour among adolescents with criminal attempts in Turkey. The study included 65 adolescents with criminal attempts (32 intervention, 33 control). There was no difference between the groups in terms of average age (16.13±1.10 in the experimental group and 16.21±0.89 in the control group). After the intervention, the experimental group showed significantly decreased Trait Anger levels (t=1.906; P=0.033), increased Anger Control scores (t=2.522; P=0.008), decreased Physical Aggression scores (t=1.925; P=0.031), decreased Hostility scores (t=2.496; P=0.009), increased Social Problem Solving total scores (t=2.937; P=0.005). Increased Anger Control scores were found to be significant when compared with the control group (t=2.273, P=0.026). These results showed that ART was effective on problem solving, anger and aggressive behaviour and can be used to develop positive behaviours among adolescents with criminal attempts. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of the impact of 2 years of a dosing intervention on canine echinococcosis in the Alay Valley, Kyrgyzstan.

PubMed

VAN Kesteren, F; Mastin, A; Torgerson, P R; Mytynova, Bermet; Craig, P S

2017-09-01

Echinococcosis is a re-emerging zoonotic disease in Kyrgyzstan. In 2012, an echinococcosis control scheme was started that included dosing owned dogs in the Alay Valley, Kyrgyzstan with praziquantel. Control programmes require large investments of money and resources; as such it is important to evaluate how well these are meeting their targets. However, problems associated with echinococcosis control schemes include remoteness and semi-nomadic customs of affected communities, and lack of resources. These same problems apply to control scheme evaluations, and quick and easy assessment tools are highly desirable. Lot quality assurance sampling was used to assess the impact of approximately 2 years of echinococcosis control in the Alay valley. A pre-intervention coproELISA prevalence was established, and a 75% threshold for dosing compliance was set based on previous studies. Ten communities were visited in 2013 and 2014, with 18-21 dogs sampled per community, and questionnaires administered to dog owners. After 21 months of control efforts, 8/10 communities showed evidence of reaching the 75% praziquantel dosing target, although only 3/10 showed evidence of a reduction in coproELISA prevalence. This is understandable, since years of sustained control are required to effectively control echinococcosis, and efforts in the Alay valley should be and are being continued.

Efficacy of an internet-based problem-solving training for teachers: results of a randomized controlled trial.

PubMed

Ebert, David Daniel; Lehr, Dirk; Boß, Leif; Riper, Heleen; Cuijpers, Pim; Andersson, Gerhard; Thiart, Hanne; Heber, Elena; Berking, Matthias

2014-11-01

The primary purpose of this randomized controlled trial (RCT) was to evaluate the efficacy of internet-based problem-solving training (iPST) for employees in the educational sector (teachers) with depressive symptoms. The results of training were compared to those of a waitlist control group (WLC). One-hundred and fifty teachers with elevated depressive symptoms (Center for Epidemiologic Studies Depression Scale, CES-D ≥16) were assigned to either the iPST or WLC group. The iPST consisted of five lessons, including problem-solving and rumination techniques. Symptoms were assessed before the intervention began and in follow-up assessments after seven weeks, three months, and six months. The primary outcome was depressive symptom severity (CES-D). Secondary outcomes included general and work-specific self-efficacy, perceived stress, pathological worries, burnout symptoms, general physical and mental health, and absenteeism. iPST participants displayed a significantly greater reduction in depressive symptoms after the intervention (d=0.59, 95% CI 0.26-0.92), after three months (d=0.37, 95% CI 0.05-0.70) and after six months (d=0.38, 95% CI 0.05-0.70) compared to the control group. The iPST participants also displayed significantly higher improvements in secondary outcomes. However, workplace absenteeism was not significantly affected. iPST is effective in reducing symptoms of depression among teachers. Disseminated on a large scale, iPST could contribute to reducing the burden of stress-related mental health problems among teachers. Future studies should evaluate iPST approaches for use in other working populations.

Aerospace applications of integer and combinatorial optimization

NASA Technical Reports Server (NTRS)

Padula, S. L.; Kincaid, R. K.

1995-01-01

Research supported by NASA Langley Research Center includes many applications of aerospace design optimization and is conducted by teams of applied mathematicians and aerospace engineers. This paper investigates the benefits from this combined expertise in solving combinatorial optimization problems. Applications range from the design of large space antennas to interior noise control. A typical problem, for example, seeks the optimal locations for vibration-damping devices on a large space structure and is expressed as a mixed/integer linear programming problem with more than 1500 design variables.

Subjective Cognitive Complaints and Functional Disability in Patients With Borderline Personality Disorder and Their Nonaffected First-Degree Relatives

PubMed Central

Ruocco, Anthony C; Lam, Jaeger; McMain, Shelley F

2014-01-01

Objective: To examine the contributions of subjective cognitive complaints to functional disability in patients with borderline personality disorder (BPD) and their nonaffected relatives. Method: Patients with BPD (n = 26), their first-degree biological relatives (n = 17), and nonpsychiatric control subjects (n = 31) completed a self-report measure of cognitive difficulties and rated the severity of their functional disability on the World Health Organization Disability Assessment Schedule 2.0. Results: After accounting for group differences in age and severity of depressive symptoms, patients and relatives endorsed more inattention and memory problems than control subjects. Whereas probands reported greater disability than relatives and control subjects across all functional domains, relatives described more difficulties than control subjects in managing multiple life activities, including domestic activities and occupational and academic functioning, and participating in society. For both probands and relatives, inattention and memory problems were linked primarily to difficulties with life activities, independent of depression and other comorbid psychiatric disorders. Conclusions: Problems with inattention and forgetfulness may lead to difficulties carrying out activities of daily living and occupational or academic problems in patients with BPD, as well as their nonaffected first-degree relatives. PMID:25007408

Subjective cognitive complaints and functional disability in patients with borderline personality disorder and their nonaffected first-degree relatives.

PubMed

Ruocco, Anthony C; Lam, Jaeger; McMain, Shelley F

2014-06-01

To examine the contributions of subjective cognitive complaints to functional disability in patients with borderline personality disorder (BPD) and their nonaffected relatives. Patients with BPD (n = 26), their first-degree biological relatives (n = 17), and nonpsychiatric control subjects (n = 31) completed a self-report measure of cognitive difficulties and rated the severity of their functional disability on the World Health Organization Disability Assessment Schedule 2.0. After accounting for group differences in age and severity of depressive symptoms, patients and relatives endorsed more inattention and memory problems than control subjects. Whereas probands reported greater disability than relatives and control subjects across all functional domains, relatives described more difficulties than control subjects in managing multiple life activities, including domestic activities and occupational and academic functioning, and participating in society. For both probands and relatives, inattention and memory problems were linked primarily to difficulties with life activities, independent of depression and other comorbid psychiatric disorders. Problems with inattention and forgetfulness may lead to difficulties carrying out activities of daily living and occupational or academic problems in patients with BPD, as well as their nonaffected first-degree relatives.

Validation of the Inventory of Interpersonal Problems (IIP-64): a comparison of Swedish female outpatients with anorexia nervosa or bulimia nervosa and controls.

PubMed

Lindberg, Karolin; Nevonen, Lauri; Gustafsson, Sanna Aila; Nyman-Carlsson, Erika; Norring, Claes

2018-04-27

The aim of the study was to explore the psychometric properties of the Inventory of Interpersonal Problems (IIP-64) and to compare levels of interpersonal distress in Swedish female outpatients with anorexia nervosa or bulimia nervosa with age- and gender-matched controls. Totally, 401 participants were included; anorexia nervosa (n = 74), bulimia nervosa (n = 85) and controls (n = 242). All participants completed the IIP-64. The eating disorder (ED) patients also filled out the Eating Disorder Inventory-2/3 (EDI). Internal consistency of IIP-64 was acceptable to high. Principal component analyses with varimax rotation of the IIP-64 subscales confirmed the circumplex structure with two underlying orthogonal dimensions; affiliation and dominance. Significant correlations between EDI-3 composite scales ineffectiveness and interpersonal problems and IIP-64 were found. ED patients reported higher levels of interpersonal distress than controls on all but one subscale (intrusive/needy). IIP-64 can be considered to have acceptable to good reliability and validity in a Swedish ED sample. IIP-64 can be a useful complement in assessment of interpersonal problems in ED.

Contribution of Equal-Sign Instruction beyond Word-Problem Tutoring for Third-Grade Students with Mathematics Difficulty

PubMed Central

Powell, Sarah R.; Fuchs, Lynn S.

2010-01-01

Elementary school students often misinterpret the equal sign (=) as an operational rather than a relational symbol. Such misunderstanding is problematic because solving equations with missing numbers may be important for higher-order mathematics skills including word problems. Research indicates equal-sign instruction can alter how typically-developing students use the equal sign, but no study has examined effects for students with mathematics difficulty (MD) or how equal-sign instruction contributes to word-problem skill for students with or without MD. The present study assessed the efficacy of equal-sign instruction within word-problem tutoring. Third-grade students with MD (n = 80) were assigned to word-problem tutoring, word-problem tutoring plus equal-sign instruction (combined) tutoring, or no-tutoring control. Combined tutoring produced better improvement on equal sign tasks and open equations compared to the other 2 conditions. On certain forms of word problems, combined tutoring but not word-problem tutoring alone produced better improvement than control. When compared at posttest to 3rd-grade students without MD on equal sign tasks and open equations, only combined tutoring students with MD performed comparably. PMID:20640240

ORACLS- OPTIMAL REGULATOR ALGORITHMS FOR THE CONTROL OF LINEAR SYSTEMS (CDC VERSION)

NASA Technical Reports Server (NTRS)

Armstrong, E. S.

1994-01-01

This control theory design package, called Optimal Regulator Algorithms for the Control of Linear Systems (ORACLS), was developed to aid in the design of controllers and optimal filters for systems which can be modeled by linear, time-invariant differential and difference equations. Optimal linear quadratic regulator theory, currently referred to as the Linear-Quadratic-Gaussian (LQG) problem, has become the most widely accepted method of determining optimal control policy. Within this theory, the infinite duration time-invariant problems, which lead to constant gain feedback control laws and constant Kalman-Bucy filter gains for reconstruction of the system state, exhibit high tractability and potential ease of implementation. A variety of new and efficient methods in the field of numerical linear algebra have been combined into the ORACLS program, which provides for the solution to time-invariant continuous or discrete LQG problems. The ORACLS package is particularly attractive to the control system designer because it provides a rigorous tool for dealing with multi-input and multi-output dynamic systems in both continuous and discrete form. The ORACLS programming system is a collection of subroutines which can be used to formulate, manipulate, and solve various LQG design problems. The ORACLS program is constructed in a manner which permits the user to maintain considerable flexibility at each operational state. This flexibility is accomplished by providing primary operations, analysis of linear time-invariant systems, and control synthesis based on LQG methodology. The input-output routines handle the reading and writing of numerical matrices, printing heading information, and accumulating output information. The basic vector-matrix operations include addition, subtraction, multiplication, equation, norm construction, tracing, transposition, scaling, juxtaposition, and construction of null and identity matrices. The analysis routines provide for the following computations: the eigenvalues and eigenvectors of real matrices; the relative stability of a given matrix; matrix factorization; the solution of linear constant coefficient vector-matrix algebraic equations; the controllability properties of a linear time-invariant system; the steady-state covariance matrix of an open-loop stable system forced by white noise; and the transient response of continuous linear time-invariant systems. The control law design routines of ORACLS implement some of the more common techniques of time-invariant LQG methodology. For the finite-duration optimal linear regulator problem with noise-free measurements, continuous dynamics, and integral performance index, a routine is provided which implements the negative exponential method for finding both the transient and steady-state solutions to the matrix Riccati equation. For the discrete version of this problem, the method of backwards differencing is applied to find the solutions to the discrete Riccati equation. A routine is also included to solve the steady-state Riccati equation by the Newton algorithms described by Klein, for continuous problems, and by Hewer, for discrete problems. Another routine calculates the prefilter gain to eliminate control state cross-product terms in the quadratic performance index and the weighting matrices for the sampled data optimal linear regulator problem. For cases with measurement noise, duality theory and optimal regulator algorithms are used to calculate solutions to the continuous and discrete Kalman-Bucy filter problems. Finally, routines are included to implement the continuous and discrete forms of the explicit (model-in-the-system) and implicit (model-in-the-performance-index) model following theory. These routines generate linear control laws which cause the output of a dynamic time-invariant system to track the output of a prescribed model. In order to apply ORACLS, the user must write an executive (driver) program which inputs the problem coefficients, formulates and selects the routines to be used to solve the problem, and specifies the desired output. There are three versions of ORACLS source code available for implementation: CDC, IBM, and DEC. The CDC version has been implemented on a CDC 6000 series computer with a central memory of approximately 13K (octal) of 60 bit words. The CDC version is written in FORTRAN IV, was developed in 1978, and last updated in 1989. The IBM version has been implemented on an IBM 370 series computer with a central memory requirement of approximately 300K of 8 bit bytes. The IBM version is written in FORTRAN IV and was generated in 1981. The DEC version has been implemented on a VAX series computer operating under VMS. The VAX version is written in FORTRAN 77 and was generated in 1986.

ORACLS- OPTIMAL REGULATOR ALGORITHMS FOR THE CONTROL OF LINEAR SYSTEMS (DEC VAX VERSION)

NASA Technical Reports Server (NTRS)

Frisch, H.

1994-01-01

This control theory design package, called Optimal Regulator Algorithms for the Control of Linear Systems (ORACLS), was developed to aid in the design of controllers and optimal filters for systems which can be modeled by linear, time-invariant differential and difference equations. Optimal linear quadratic regulator theory, currently referred to as the Linear-Quadratic-Gaussian (LQG) problem, has become the most widely accepted method of determining optimal control policy. Within this theory, the infinite duration time-invariant problems, which lead to constant gain feedback control laws and constant Kalman-Bucy filter gains for reconstruction of the system state, exhibit high tractability and potential ease of implementation. A variety of new and efficient methods in the field of numerical linear algebra have been combined into the ORACLS program, which provides for the solution to time-invariant continuous or discrete LQG problems. The ORACLS package is particularly attractive to the control system designer because it provides a rigorous tool for dealing with multi-input and multi-output dynamic systems in both continuous and discrete form. The ORACLS programming system is a collection of subroutines which can be used to formulate, manipulate, and solve various LQG design problems. The ORACLS program is constructed in a manner which permits the user to maintain considerable flexibility at each operational state. This flexibility is accomplished by providing primary operations, analysis of linear time-invariant systems, and control synthesis based on LQG methodology. The input-output routines handle the reading and writing of numerical matrices, printing heading information, and accumulating output information. The basic vector-matrix operations include addition, subtraction, multiplication, equation, norm construction, tracing, transposition, scaling, juxtaposition, and construction of null and identity matrices. The analysis routines provide for the following computations: the eigenvalues and eigenvectors of real matrices; the relative stability of a given matrix; matrix factorization; the solution of linear constant coefficient vector-matrix algebraic equations; the controllability properties of a linear time-invariant system; the steady-state covariance matrix of an open-loop stable system forced by white noise; and the transient response of continuous linear time-invariant systems. The control law design routines of ORACLS implement some of the more common techniques of time-invariant LQG methodology. For the finite-duration optimal linear regulator problem with noise-free measurements, continuous dynamics, and integral performance index, a routine is provided which implements the negative exponential method for finding both the transient and steady-state solutions to the matrix Riccati equation. For the discrete version of this problem, the method of backwards differencing is applied to find the solutions to the discrete Riccati equation. A routine is also included to solve the steady-state Riccati equation by the Newton algorithms described by Klein, for continuous problems, and by Hewer, for discrete problems. Another routine calculates the prefilter gain to eliminate control state cross-product terms in the quadratic performance index and the weighting matrices for the sampled data optimal linear regulator problem. For cases with measurement noise, duality theory and optimal regulator algorithms are used to calculate solutions to the continuous and discrete Kalman-Bucy filter problems. Finally, routines are included to implement the continuous and discrete forms of the explicit (model-in-the-system) and implicit (model-in-the-performance-index) model following theory. These routines generate linear control laws which cause the output of a dynamic time-invariant system to track the output of a prescribed model. In order to apply ORACLS, the user must write an executive (driver) program which inputs the problem coefficients, formulates and selects the routines to be used to solve the problem, and specifies the desired output. There are three versions of ORACLS source code available for implementation: CDC, IBM, and DEC. The CDC version has been implemented on a CDC 6000 series computer with a central memory of approximately 13K (octal) of 60 bit words. The CDC version is written in FORTRAN IV, was developed in 1978, and last updated in 1986. The IBM version has been implemented on an IBM 370 series computer with a central memory requirement of approximately 300K of 8 bit bytes. The IBM version is written in FORTRAN IV and was generated in 1981. The DEC version has been implemented on a VAX series computer operating under VMS. The VAX version is written in FORTRAN 77 and was generated in 1986.

Environmental Compliance Assessment System (ECAS) - Japan Settlement

DTIC Science & Technology

1993-12-01

pollution control which take into account the specific natural and social conditions of the concerned area. Prefectural governments are responsible mainly...out possible environmental problems, as well as practices, conditions , and situations that could indicate potential problems. They are intended to...soot and smoke emitting facility, or a person installing a particu- late discharging facility, to report certain matters. These include the conditions

Summary of research in applied mathematics, numerical analysis, and computer sciences

NASA Technical Reports Server (NTRS)

1986-01-01

The major categories of current ICASE research programs addressed include: numerical methods, with particular emphasis on the development and analysis of basic numerical algorithms; control and parameter identification problems, with emphasis on effective numerical methods; computational problems in engineering and physical sciences, particularly fluid dynamics, acoustics, and structural analysis; and computer systems and software, especially vector and parallel computers.

Programs for Prevention of Externalizing Problems in Children: Limited Evidence for Effect beyond 6 Months Post Intervention

ERIC Educational Resources Information Center

Smedler, Ann-Charlotte; Hjern, Anders; Wiklund, Stefan; Anttila, Sten; Pettersson, Agneta

2015-01-01

Background: Preventing externalizing problems in children is a major societal concern, and a great number of intervention programs have been developed to this aim. To evaluate their preventive effects, well-controlled trials including follow-up assessments are necessary. Methods: This is a systematic review of the effect of prevention programs…

40 CFR 63.4567 - How do I establish the emission capture system and add-on control device operating limits during...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Hazardous Air Pollutants for Surface Coating of Plastic Parts and Products Compliance Requirements for the... procedures. If problems are found during the catalyst activity test, you must replace the catalyst bed or... inspection of the catalytic oxidizer system, including the burner assembly and fuel supply lines for problems...

40 CFR 63.4567 - How do I establish the emission capture system and add-on control device operating limits during...

Code of Federal Regulations, 2011 CFR

2011-07-01

... Hazardous Air Pollutants for Surface Coating of Plastic Parts and Products Compliance Requirements for the... procedures. If problems are found during the catalyst activity test, you must replace the catalyst bed or... inspection of the catalytic oxidizer system, including the burner assembly and fuel supply lines for problems...

The Teaching of General Solution Methods to Pattern Finding Problems through Focusing on an Evaluation and Improvement Process.

ERIC Educational Resources Information Center

Ishida, Junichi

1997-01-01

Examines the effects of a teaching strategy in which fifth-grade students evaluated the strengths or weaknesses of solution methods to pattern finding problems, including an experimental and control group each consisting of 34 elementary students, in Japan. The experimental group showed a significantly better performance on the retention test…

Strategic and non-strategic problem gamblers differ on decision-making under risk and ambiguity.

PubMed

Lorains, Felicity K; Dowling, Nicki A; Enticott, Peter G; Bradshaw, John L; Trueblood, Jennifer S; Stout, Julie C

2014-07-01

To analyse problem gamblers' decision-making under conditions of risk and ambiguity, investigate underlying psychological factors associated with their choice behaviour and examine whether decision-making differed in strategic (e.g., sports betting) and non-strategic (e.g., electronic gaming machine) problem gamblers. Cross-sectional study. Out-patient treatment centres and university testing facilities in Victoria, Australia. Thirty-nine problem gamblers and 41 age, gender and estimated IQ-matched controls. Decision-making tasks included the Iowa Gambling Task (IGT) and a loss aversion task. The Prospect Valence Learning (PVL) model was used to provide an explanation of cognitive, motivational and response style factors involved in IGT performance. Overall, problem gamblers performed more poorly than controls on both the IGT (P = 0.04) and the loss aversion task (P = 0.01), and their IGT decisions were associated with heightened attention to gains (P = 0.003) and less consistency (P = 0.002). Strategic problem gamblers did not differ from matched controls on either decision-making task, but non-strategic problem gamblers performed worse on both the IGT (P = 0.006) and the loss aversion task (P = 0.02). Furthermore, we found differences in the PVL model parameters underlying strategic and non-strategic problem gamblers' choices on the IGT. Problem gamblers demonstrated poor decision-making under conditions of risk and ambiguity. Strategic (e.g. sports betting, poker) and non-strategic (e.g. electronic gaming machines) problem gamblers differed in decision-making and the underlying psychological processes associated with their decisions. © 2014 Society for the Study of Addiction.

Quadratic constrained mixed discrete optimization with an adiabatic quantum optimizer

NASA Astrophysics Data System (ADS)

Chandra, Rishabh; Jacobson, N. Tobias; Moussa, Jonathan E.; Frankel, Steven H.; Kais, Sabre

2014-07-01

We extend the family of problems that may be implemented on an adiabatic quantum optimizer (AQO). When a quadratic optimization problem has at least one set of discrete controls and the constraints are linear, we call this a quadratic constrained mixed discrete optimization (QCMDO) problem. QCMDO problems are NP-hard, and no efficient classical algorithm for their solution is known. Included in the class of QCMDO problems are combinatorial optimization problems constrained by a linear partial differential equation (PDE) or system of linear PDEs. An essential complication commonly encountered in solving this type of problem is that the linear constraint may introduce many intermediate continuous variables into the optimization while the computational cost grows exponentially with problem size. We resolve this difficulty by developing a constructive mapping from QCMDO to quadratic unconstrained binary optimization (QUBO) such that the size of the QUBO problem depends only on the number of discrete control variables. With a suitable embedding, taking into account the physical constraints of the realizable coupling graph, the resulting QUBO problem can be implemented on an existing AQO. The mapping itself is efficient, scaling cubically with the number of continuous variables in the general case and linearly in the PDE case if an efficient preconditioner is available.

Cerebellar Disorders

MedlinePlus

... hit a tennis ball you are activating the cerebellum. The cerebellum is the area of the brain that controls coordination and balance. Problems with the cerebellum include Cancer Genetic disorders Ataxias - failure of muscle ...

Microprocessors in Schools?

ERIC Educational Resources Information Center

Cuthbert, L. G.

1981-01-01

Examines reasons for including microprocessors in school curricula. Indicates that practical work with microprocessors is not easy and discusses problems associated with using and constructing these control and processing devices of microcomputers. (SK)

CONSOLE: A CAD tandem for optimization-based design interacting with user-supplied simulators

NASA Technical Reports Server (NTRS)

Fan, Michael K. H.; Wang, Li-Sheng; Koninckx, Jan; Tits, Andre L.

1989-01-01

CONSOLE employs a recently developed design methodology (International Journal of Control 43:1693-1721) which provides the designer with a congenial environment to express his problem as a multiple ojective constrained optimization problem and allows him to refine his characterization of optimality when a suboptimal design is approached. To this end, in CONSOLE, the designed formulates the design problem using a high-level language and performs design task and explores tradeoff through a few short and clearly defined commands. The range of problems that can be solved efficiently using a CAD tools depends very much on the ability of this tool to be interfaced with user-supplied simulators. For instance, when designing a control system one makes use of the characteristics of the plant, and therefore, a model of the plant under study has to be made available to the CAD tool. CONSOLE allows for an easy interfacing of almost any simulator the user has available. To date CONSOLE has already been used successfully in many applications, including the design of controllers for a flexible arm and for a robotic manipulator and the solution of a parameter selection problem for a neural network.

Prevention of adolescent problem behavior: longitudinal impact of the Project P.A.T.H.S. in Hong Kong.

PubMed

Shek, Daniel T L; Yu, Lu

2011-03-07

The present study attempts to examine the longitudinal impact of a curriculum-based positive youth development program, entitled the Project P.A.T.H.S. (Positive Adolescent Training through Holistic Social Programmes), on adolescent problem behavior in Hong Kong. Using a longitudinal randomized group design, six waves of data were collected from 19 experimental schools (n = 3,797 at Wave 1) in which students participated in the Project P.A.T.H.S. and 24 control schools (n = 4,049 at Wave 1). At each wave, students responded to questions asking about their current problem behaviors, including delinquency and use of different types of drugs, and their intentions of engaging in such behaviors in the future. Results based on individual growth curve modeling generally showed that the participants displayed lower levels of substance abuse and delinquent behavior than did the control students. Participants who regarded the program to be helpful also showed lower levels of problem behavior than did the control students. The present findings suggest that the Project P.A.T.H.S. is effective in preventing adolescent problem behavior in the junior secondary school years.

Impact of neonatal risk and temperament on behavioral problems in toddlers born preterm.

PubMed

Guilherme Monte Cassiano, Rafaela; Gaspardo, Claudia Maria; Cordaro Bucker Furini, Guilherme; Martinez, Francisco Eulogio; Martins Linhares, Maria Beatriz

2016-12-01

Children born preterm are at risk for later developmental disorders. The present study examined the predictive effects of neonatal, sociodemographic, and temperament characteristics on behavioral outcomes at toddlerhood, in children born preterm. The sample included 100 toddlers born preterm and with very-low-birth-weight, and their mothers. Neonatal characteristics were evaluated using medical records. The mothers were interviewed using the Early Childhood Behavior Questionnaire for temperament assessment, and the Child Behavior Checklist for behavioral assessment. Multiple linear regression analyses were performed. Predictors of 39% of the variability of the total behavioral problems in toddlers born prematurely were: temperament with more Negative Affectivity and less Effortful Control, lower family socioeconomic status, and younger mothers at childbirth. Temperament with more Negative Affectivity and less Effortful Control and lower family socioeconomic status were predictors of 23% of the variability of internalizing behavioral problems. Additionally, 37% of the variability of externalizing behavioral problems was explained by temperament with more Negative Affectivity and less Effortful Control, and younger mothers at childbirth. The neonatal characteristics and stressful events in the neonatal intensive care unit did not predict behavioral problems at toddlerhood. However, temperament was a consistent predictor of behavioral problems in toddlers born preterm. Preventive follow-up programs could assess dispositional traits of temperament to provide early identification of preterm infants at high-risk for behavioral problems. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ride comfort control in large flexible aircraft. M.S. Thesis

NASA Technical Reports Server (NTRS)

Warren, M. E.

1971-01-01

The problem of ameliorating the discomfort of passengers on a large air transport subject to flight disturbances is examined. The longitudinal dynamics of the aircraft, including effects of body flexing, are developed in terms of linear, constant coefficient differential equations in state variables. A cost functional, penalizing the rigid body displacements and flexure accelerations over the surface of the aircraft is formulated as a quadratic form. The resulting control problem, to minimize the cost subject to the state equation constraints, is of a class whose solutions are well known. The feedback gains for the optimal controller are calculated digitally, and the resulting autopilot is simulated on an analog computer and its performance evaluated.

A parametric LQ approach to multiobjective control system design

NASA Technical Reports Server (NTRS)

Kyr, Douglas E.; Buchner, Marc

1988-01-01

The synthesis of a constant parameter output feedback control law of constrained structure is set in a multiple objective linear quadratic regulator (MOLQR) framework. The use of intuitive objective functions such as model-following ability and closed-loop trajectory sensitivity, allow multiple objective decision making techniques, such as the surrogate worth tradeoff method, to be applied. For the continuous-time deterministic problem with an infinite time horizon, dynamic compensators as well as static output feedback controllers can be synthesized using a descent Anderson-Moore algorithm modified to impose linear equality constraints on the feedback gains by moving in feasible directions. Results of three different examples are presented, including a unique reformulation of the sensitivity reduction problem.

Virtual Reality: Directions in Research and Development.

ERIC Educational Resources Information Center

Stuart, Rory

1992-01-01

Discussion of virtual reality (VR) focuses on research and development being carried out at NYNEX to solve business problems. Component technologies are described; design decisions are considered, including interactivity, connectivity, and locus of control; potential perils of VR are discussed, including user dissociation; and areas of promise are…

A genetically informed test of cholesterol levels and self-control, depressive symptoms, antisocial behavior, and neuroticism.

PubMed

Schwartz, Joseph A; Rowland, Meghan W; Beaver, Kevin M

2014-08-01

Low cholesterol levels have been found to be associated with a wide range of behavioral problems, including violent and criminal behavior, and a wide range of psychological problems including impulsivity, depression, and other internalizing problems. The casual mechanisms underlying these associations remain largely unknown, but genetic factors may play a role in the etiology of such associations as previous research has found significant genetic influence on cholesterol levels and various deleterious behavioral and psychological outcomes. The current study addressed this existing gap in the literature by performing a genetically sensitive test of the association between cholesterol levels and various outcomes including levels of self-control, depressive symptoms, anger expression, and neuroticism. DeFries-Fulker (DF) analysis was used to analyze data from 388 twin pairs nested within the Survey of Midlife Development in the United States (MIDUS). The results of the genetically informed models revealed that high-density lipoprotein (HDL) cholesterol levels were negatively and significantly associated with depressive symptoms, had a marginally significant effect on neuroticism, and a nonsignificant effect on both anger expression and self-control. The findings may not extrapolate to the larger population of American adults since the subsample of twins with cholesterol information may not be nationally representative. Genetic influences play a significant role in the association between cholesterol levels and various deleterious outcomes and failing to control for these influences may result in model misspecification and may increase the probability of detecting a significant association when one does not actually exist. Copyright © 2014 Elsevier B.V. All rights reserved.

Cable compliance

NASA Technical Reports Server (NTRS)

Kerley, J.; Eklund, W.; Burkhardt, R.; Rossoni, P.

1992-01-01

The object of the investigation was to solve mechanical problems using cable-in-bending and cable-in-torsion. These problems included robotic contacts, targets, and controls using cable compliance. Studies continued in the use of cable compliance for the handicapped and the elderly. These included work stations, walkers, prosthetic knee joints, elbow joints, and wrist joints. More than half of these objects were met, and models were made and studies completed on most of the others. It was concluded that the many different and versatile solutions obtained only opened the door to many future challenges.

Medical entomology--back to the future?

PubMed

Reisen, William K

2014-12-01

Some of problems and challenges facing Medical/Veterinary Entomology are presented from my perspective, focusing on the current millennium. Topics include anthropogenic environmental changes created by population growth, administrative problems hindering science's response to these changes, and some of the scientific discoveries potentially providing solutions. As the title implies, many recent research discoveries have yet to be translated into major changes in control approaches for the major vectorborne public health problems, thereby providing an interesting mix of modern surveillance technology used to track problems and direct historical intervention solutions. Copyright © 2013 Elsevier B.V. All rights reserved.

New perspectives on pollution control: Cross-media problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Although there is only one natural environment, many environmental institutions and policies attempt to control pollutants in air, water, and land separately, often by merely transferring the pollutants from one medium to another. Water pollutants may be volatilized into the air or collected and disposed of on land as sludge, thereby allowing the possibility for contamination of another medium. Present policies often fail to reduce levels of some pollutants in the overall environment. To examine this cross-media problem and what can be done about it, The conservation Foundation sponsored a conference in November 1984 on the new dimensions of pollutionmore » problems. The papers presented at that conference along with comments and additional discussion are compiled in this report. The perspectives included represent those of government officials, corporate executives, environmentalists, researchers, and others. The extent of the cross-media problem, priorities for future research, and the implications that cross-media problems have for environmental policy are considered.« less

Robust set-point regulation for ecological models with multiple management goals.

PubMed

Guiver, Chris; Mueller, Markus; Hodgson, Dave; Townley, Stuart

2016-05-01

Population managers will often have to deal with problems of meeting multiple goals, for example, keeping at specific levels both the total population and population abundances in given stage-classes of a stratified population. In control engineering, such set-point regulation problems are commonly tackled using multi-input, multi-output proportional and integral (PI) feedback controllers. Building on our recent results for population management with single goals, we develop a PI control approach in a context of multi-objective population management. We show that robust set-point regulation is achieved by using a modified PI controller with saturation and anti-windup elements, both described in the paper, and illustrate the theory with examples. Our results apply more generally to linear control systems with positive state variables, including a class of infinite-dimensional systems, and thus have broader appeal.

A hierarchical framework for air traffic control

NASA Astrophysics Data System (ADS)

Roy, Kaushik

Air travel in recent years has been plagued by record delays, with over $8 billion in direct operating costs being attributed to 100 million flight delay minutes in 2007. Major contributing factors to delay include weather, congestion, and aging infrastructure; the Next Generation Air Transportation System (NextGen) aims to alleviate these delays through an upgrade of the air traffic control system. Changes to large-scale networked systems such as air traffic control are complicated by the need for coordinated solutions over disparate temporal and spatial scales. Individual air traffic controllers must ensure aircraft maintain safe separation locally with a time horizon of seconds to minutes, whereas regional plans are formulated to efficiently route flows of aircraft around weather and congestion on the order of every hour. More efficient control algorithms that provide a coordinated solution are required to safely handle a larger number of aircraft in a fixed amount of airspace. Improved estimation algorithms are also needed to provide accurate aircraft state information and situational awareness for human controllers. A hierarchical framework is developed to simultaneously solve the sometimes conflicting goals of regional efficiency and local safety. Careful attention is given in defining the interactions between the layers of this hierarchy. In this way, solutions to individual air traffic problems can be targeted and implemented as needed. First, the regional traffic flow management problem is posed as an optimization problem and shown to be NP-Hard. Approximation methods based on aggregate flow models are developed to enable real-time implementation of algorithms that reduce the impact of congestion and adverse weather. Second, the local trajectory design problem is solved using a novel slot-based sector model. This model is used to analyze sector capacity under varying traffic patterns, providing a more comprehensive understanding of how increased automation in NextGen will affect the overall performance of air traffic control. The dissertation also provides solutions to several key estimation problems that support corresponding control tasks. Throughout the development of these estimation algorithms, aircraft motion is modeled using hybrid systems, which encapsulate both the discrete flight mode of an aircraft and the evolution of continuous states such as position and velocity. The target-tracking problem is posed as one of hybrid state estimation, and two new algorithms are developed to exploit structure specific to aircraft motion, especially near airports. First, discrete mode evolution is modeled using state-dependent transitions, in which the likelihood of changing flight modes is dependent on aircraft state. Second, an estimator is designed for systems with limited mode changes, including arrival aircraft. Improved target tracking facilitates increased safety in collision avoidance and trajectory design problems. A multiple-target tracking and identity management algorithm is developed to improve situational awareness for controllers about multiple maneuvering targets in a congested region. Finally, tracking algorithms are extended to predict aircraft landing times; estimated time of arrival prediction is one example of important decision support information for air traffic control.

Target Capturing Control for Space Robots with Unknown Mass Properties: A Self-Tuning Method Based on Gyros and Cameras.

PubMed

Li, Zhenyu; Wang, Bin; Liu, Hong

2016-08-30

Satellite capturing with free-floating space robots is still a challenging task due to the non-fixed base and unknown mass property issues. In this paper gyro and eye-in-hand camera data are adopted as an alternative choice for solving this problem. For this improved system, a new modeling approach that reduces the complexity of system control and identification is proposed. With the newly developed model, the space robot is equivalent to a ground-fixed manipulator system. Accordingly, a self-tuning control scheme is applied to handle such a control problem including unknown parameters. To determine the controller parameters, an estimator is designed based on the least-squares technique for identifying the unknown mass properties in real time. The proposed method is tested with a credible 3-dimensional ground verification experimental system, and the experimental results confirm the effectiveness of the proposed control scheme.

Target Capturing Control for Space Robots with Unknown Mass Properties: A Self-Tuning Method Based on Gyros and Cameras

PubMed Central

Li, Zhenyu; Wang, Bin; Liu, Hong

2016-01-01

Satellite capturing with free-floating space robots is still a challenging task due to the non-fixed base and unknown mass property issues. In this paper gyro and eye-in-hand camera data are adopted as an alternative choice for solving this problem. For this improved system, a new modeling approach that reduces the complexity of system control and identification is proposed. With the newly developed model, the space robot is equivalent to a ground-fixed manipulator system. Accordingly, a self-tuning control scheme is applied to handle such a control problem including unknown parameters. To determine the controller parameters, an estimator is designed based on the least-squares technique for identifying the unknown mass properties in real time. The proposed method is tested with a credible 3-dimensional ground verification experimental system, and the experimental results confirm the effectiveness of the proposed control scheme. PMID:27589748

Perceived Competency and Resolution of Homelessness Among Women with Substance Abuse Problems

PubMed Central

Finfgeld-Connett, Deborah; Bloom, Tina L.; Johnson, E. Diane

2011-01-01

Using a metasynthesis approach, our aim was to articulate new insights relating to the most efficient and effective means of helping homeless women with substance abuse problems to enhance their well-being and become more stably housed. Distorted perceptions of competency, which are shaped by dysfunctional relationships and mental health problems, make it challenging for women with substance abuse problems to resolve homelessness. Women with particularly low or high levels of perceived competency tend to grapple with challenges related to structure and control, trust, and hopelessness. Therapeutic strategies for approaching these women include careful assessment, caring, personalized structure and control, development of interpersonal trust, instillation of hope, and the targeted use of psychotherapeutic agents and counseling. Framing care for homeless women within the context of perceived competency offers a new way of understanding their plight and shaping interventions to more expeditiously move them toward healthy and stable lives. PMID:21890717

Perceived competency and resolution of homelessness among women with substance abuse problems.

PubMed

Finfgeld-Connett, Deborah; Bloom, Tina L; Johnson, E Diane

2012-03-01

Using a metasynthesis approach, our aim was to articulate new insights relating to the most efficient and effective means of helping homeless women with substance abuse problems to enhance their well-being and become more stably housed. Distorted perceptions of competency, which are shaped by dysfunctional relationships and mental health problems, make it challenging for women with substance abuse problems to resolve homelessness. Women with particularly low or high levels of perceived competency tend to grapple with challenges related to structure and control, trust, and hopelessness. Therapeutic strategies for approaching these women include careful assessment, caring, personalized structure and control, development of interpersonal trust, instillation of hope, and the targeted use of psychotherapeutic agents and counseling. Framing care for homeless women within the context of perceived competency offers a new way of understanding their plight and shaping interventions to more expeditiously move them toward healthy and stable lives.

A cross-sectional observational study comparing foot and ankle characteristics in people with stroke and healthy controls.

PubMed

Kunkel, Dorit; Potter, Julia; Mamode, Louis

2017-06-01

The purpose of this study was to explore and compare foot and ankle characteristics in people with stroke and healthy controls; and between stroke fallers and non-fallers. Participants were recruited from community groups and completed standardized tests assessing sensation, foot posture, foot function, ankle dorsiflexion and first metatarsal phalangeal joint range of motion (1st MPJ ROM), hallux valgus presence and severity. Twenty-three stroke participants (mean age 75.09 ± 7.57 years; 12 fallers) and 16 controls (mean age 73.44 ± 8.35 years) took part. Within the stroke group, reduced 1st MPJ sensation (p = 0.016) and 1st MPJ ROM (p = 0.025) were observed in the affected foot in comparison to the non-affected foot; no other differences were apparent. Pooled data (for both feet) was used to explore between stroke/control (n = 78 feet) and stroke faller/non-faller (n = 46 feet) group differences. In comparison to the control group, stroke participants exhibited reduced sensation of the 1st MPJ (p = 0.020), higher Foot Posture Index scores (indicating greater foot pronation, p = 0.008) and reduced foot function (p = 0.003). Stroke fallers exhibited significantly greater foot pronation in comparison to non-fallers (p = 0.027). Results indicated differences in foot and ankle characteristics post stroke in comparison to healthy controls. These changes may negatively impact functional ability and the ability to preserve balance. Further research is warranted to explore the influence of foot problems on balance ability and falls in people with stroke. Implications for Rehabilitation Foot problems are common post stroke. As foot problems have been linked to increased fall risk among the general population we recommend that it would be beneficial to include foot and ankle assessments or a referral to a podiatrist for people with stroke who report foot problems. Further research is needed to explore if we can improve functional performance post stroke and reduce fall risk if treatment or prevention of foot problems can be included in stroke rehabilitation.

Massage therapy research review

PubMed Central

Field, Tiffany

2017-01-01

In this review, massage therapy has been shown to have beneficial effects on varying conditions including prenatal depression, preterm infants, full-term infants, autism, skin conditions, pain syndromes including arthritis and fibromyalgia, hypertension, autoimmune conditions including asthma and multiple sclerosis, immune conditions including HIV and breast cancer and aging problems including Parkinson's and dementia. Although many of the studies have involved comparisons between massage therapy and standard treatment control groups, several have compared different forms of massage (e.g. Swedish versus Thai massage), and different active therapies such as massage versus exercise. Typically, the massage therapy groups have experienced more positive effects than the control or comparison groups. This may relate to the massage therapy providing more stimulation of pressure receptors, in turn enhancing vagal activity and reducing Cortisol levels. Some of the researchers have assessed physical, physiological and biochemical effects, although most have relied exclusively on self-report measures. Despite these methodological problems and the dearth of research from the U.S., the massage therapy profession has grown significantly and massage therapy is increasingly practiced in traditional medical settings, highlighting the need for more rigorous research. PMID:27502797

Massage therapy research review.

PubMed

Field, Tiffany

2016-08-01

In this review, massage therapy has been shown to have beneficial effects on varying conditions including prenatal depression, preterm infants, full-term infants, autism, skin conditions, pain syndromes including arthritis and fibromyalgia, hypertension, autoimmune conditions including asthma and multiple sclerosis, immune conditions including HIV and breast cancer and aging problems including Parkinson's and dementia. Although many of the studies have involved comparisons between massage therapy and standard treatment control groups, several have compared different forms of massage (e.g. Swedish versus Thai massage), and different active therapies such as massage versus exercise. Typically, the massage therapy groups have experienced more positive effects than the control or comparison groups. This may relate to the massage therapy providing more stimulation of pressure receptors, in turn enhancing vagal activity and reducing cortisol levels. Some of the researchers have assessed physical, physiological and biochemical effects, although most have relied exclusively on self-report measures. Despite these methodological problems and the dearth of research from the U.S., the massage therapy profession has grown significantly and massage therapy is increasingly practiced in traditional medical settings, highlighting the need for more rigorous research. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effectiveness of return-to-work interventions that incorporate work-focused problem-solving skills for workers with sickness absences related to mental disorders: a systematic literature review

PubMed Central

Dewa, Carolyn S; Loong, Desmond; Bonato, Sarah; Joosen, Margot C W

2015-01-01

Objectives This paper reviews the current state of the published peer-reviewed literature related to return-to-work (RTW) interventions that incorporate work-related problem-solving skills for workers with sickness absences related to mental disorders. It addresses the question: What is the evidence for the effectiveness of these RTW interventions? Design Using a multiphase screening process, this systematic literature review was based on publically available peer-reviewed studies. Five electronic databases were searched: (1) Medline Current, (2) Medline In-process, (3) PsycINFO, (4) Econlit and (5) Web of Science. Setting The focus was on RTW interventions for workers with medically certified sickness absences related to mental disorders. Participants Workers with medically certified sickness absences related to mental disorders. Interventions RTW intervention included work-focused problem-solving skills. Primary and secondary outcome measures RTW rates and length of sickness absences. Results There were 4709 unique citations identified. Of these, eight articles representing a total of six studies were included in the review. In terms of bias avoidance, two of the six studies were rated as excellent, two as good and two as weak. Five studies were from the Netherlands; one was from Norway. There was variability among the studies with regard to RTW findings. Two of three studies reported significant differences in RTW rates between the intervention and control groups. One of six studies observed a significant difference in sickness absence duration between intervention and control groups. Conclusions There is limited evidence that combinations of interventions that include work-related problem-solving skills are effective in RTW outcomes. The evidence could be strengthened if future studies included more detailed examinations of intervention adherence and changes in problem-solving skills. Future studies should also examine the long-term effects of problem-solving skills on sickness absence recurrence and work productivity. PMID:26078309

Effects of weightlessness in man.

NASA Technical Reports Server (NTRS)

Berry, C. A.

1973-01-01

The program for the Apollo 16 flight was designed to include both safeguards against and investigations of the physiological problems arising from increase in the period of manned space flight. Precautions included the provision of a controlled diet with high potassium content, carefully controlled work loads and work-rest cycles, and an emergency cardiology consultation service, and investigations were made to enable preflight vs postflight comparisons of metabolic, cardiovascular, and central nervous system data. Results of these investigations indicate that adjustment to weightlessness can be satisfactorily assisted by appropriate countermeasures, including attention to diet.

IMPROVED CORROSION RESISTANCE OF ALUMINA REFRACTORIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

John P. Hurley; Patty L. Kleven

2001-09-30

The initial objective of this project was to do a literature search to define the problems of refractory selection in the metals and glass industries. The problems fall into three categories: Economic--What do the major problems cost the industries financially? Operational--How do the major problems affect production efficiency and impact the environment? and Scientific--What are the chemical and physical mechanisms that cause the problems to occur? This report presents a summary of these problems. It was used to determine the areas in which the EERC can provide the most assistance through bench-scale and laboratory testing. The final objective of thismore » project was to design and build a bench-scale high-temperature controlled atmosphere dynamic corrosion application furnace (CADCAF). The furnace will be used to evaluate refractory test samples in the presence of flowing corrodents for extended periods, to temperatures of 1600 C under controlled atmospheres. Corrodents will include molten slag, steel, and glass. This test should prove useful for the glass and steel industries when faced with the decision of choosing the best refractory for flowing corrodent conditions.« less

Dynamic Programming and Error Estimates for Stochastic Control Problems with Maximum Cost

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bokanowski, Olivier, E-mail: boka@math.jussieu.fr; Picarelli, Athena, E-mail: athena.picarelli@inria.fr; Zidani, Hasnaa, E-mail: hasnaa.zidani@ensta.fr

2015-02-15

This work is concerned with stochastic optimal control for a running maximum cost. A direct approach based on dynamic programming techniques is studied leading to the characterization of the value function as the unique viscosity solution of a second order Hamilton–Jacobi–Bellman (HJB) equation with an oblique derivative boundary condition. A general numerical scheme is proposed and a convergence result is provided. Error estimates are obtained for the semi-Lagrangian scheme. These results can apply to the case of lookback options in finance. Moreover, optimal control problems with maximum cost arise in the characterization of the reachable sets for a system ofmore » controlled stochastic differential equations. Some numerical simulations on examples of reachable analysis are included to illustrate our approach.« less

Alternative Architectures for Distributed Cooperative Problem-Solving in the National Airspace System

NASA Technical Reports Server (NTRS)

Smith, Phillip J.; Billings, Charles; McCoy, C. Elaine; Orasanu, Judith

1999-01-01

The air traffic management system in the United States is an example of a distributed problem solving system. It has elements of both cooperative and competitive problem-solving. This system includes complex organizations such as Airline Operations Centers (AOCs), the FAA Air Traffic Control Systems Command Center (ATCSCC), and traffic management units (TMUs) at enroute centers and TRACONs, all of which have a major focus on strategic decision-making. It also includes individuals concerned more with tactical decisions (such as air traffic controllers and pilots). The architecture for this system has evolved over time to rely heavily on the distribution of tasks and control authority in order to keep cognitive complexity manageable for any one individual operator, and to provide redundancy (both human and technological) to serve as a safety net to catch the slips or mistakes that any one person or entity might make. Currently, major changes are being considered for this architecture, especially with respect to the locus of control, in an effort to improve efficiency and safety. This paper uses a series of case studies to help evaluate some of these changes from the perspective of system complexity, and to point out possible alternative approaches that might be taken to improve system performance. The paper illustrates the need to maintain a clear understanding of what is required to assure a high level of performance when alternative system architectures and decompositions are developed.

The prospective effects of workplace violence on physicians' job satisfaction and turnover intentions: the buffering effect of job control.

PubMed

Heponiemi, Tarja; Kouvonen, Anne; Virtanen, Marianna; Vänskä, Jukka; Elovainio, Marko

2014-01-17

Health care professionals, including physicians, are at high risk of encountering workplace violence. At the same time physician turnover is an increasing problem that threatens the functioning of the health care sector worldwide. The present study examined the prospective associations of work-related physical violence and bullying with physicians' turnover intentions and job satisfaction. In addition, we tested whether job control would modify these associations. The present study was a 4-year longitudinal survey study, with data gathered in 2006 and 2010.The present sample included 1515 (61% women) Finnish physicians aged 25-63 years at baseline. Analyses of covariance (ANCOVA) were conducted while adjusting for gender, age, baseline levels, specialisation status, and employment sector. The results of covariance analyses showed that physical violence led to increased physician turnover intentions and that both bullying and physical violence led to reduced physician job satisfaction even after adjustments. We also found that opportunities for job control were able to alleviate the increase in turnover intentions resulting from bullying. Our results suggest that workplace violence is an extensive problem in the health care sector and may lead to increased turnover and job dissatisfaction. Thus, health care organisations should approach this problem through different means, for example, by giving health care employees more opportunities to control their own work.

The prospective effects of workplace violence on physicians’ job satisfaction and turnover intentions: the buffering effect of job control

PubMed Central

2014-01-01

Background Health care professionals, including physicians, are at high risk of encountering workplace violence. At the same time physician turnover is an increasing problem that threatens the functioning of the health care sector worldwide. The present study examined the prospective associations of work-related physical violence and bullying with physicians’ turnover intentions and job satisfaction. In addition, we tested whether job control would modify these associations. Methods The present study was a 4-year longitudinal survey study, with data gathered in 2006 and 2010.The present sample included 1515 (61% women) Finnish physicians aged 25–63 years at baseline. Analyses of covariance (ANCOVA) were conducted while adjusting for gender, age, baseline levels, specialisation status, and employment sector. Results The results of covariance analyses showed that physical violence led to increased physician turnover intentions and that both bullying and physical violence led to reduced physician job satisfaction even after adjustments. We also found that opportunities for job control were able to alleviate the increase in turnover intentions resulting from bullying. Conclusions Our results suggest that workplace violence is an extensive problem in the health care sector and may lead to increased turnover and job dissatisfaction. Thus, health care organisations should approach this problem through different means, for example, by giving health care employees more opportunities to control their own work. PMID:24438449

Computed torque control of a free-flying cooperat ing-arm robot

NASA Technical Reports Server (NTRS)

Koningstein, Ross; Ullman, Marc; Cannon, Robert H., Jr.

1989-01-01

The unified approach to solving free-floating space robot manipulator end-point control problems is presented using a control formulation based on an extension of computed torque. Once the desired end-point accelerations have been specified, the kinematic equations are used with momentum conservation equations to solve for the joint accelerations in any of the robot's possible configurations: fixed base or free-flying with open/closed chain grasp. The joint accelerations can then be used to calculate the arm control torques and internal forces using a recursive order N algorithm. Initial experimental verification of these techniques has been performed using a laboratory model of a two-armed space robot. This fully autonomous spacecraft system experiences the drag-free, zero G characteristics of space in two dimensions through the use of an air cushion support system. Results of these initial experiments are included which validate the correctness of the proposed methodology. The further problem of control in the large where not only the manipulator tip positions but the entire system consisting of base and arms must be controlled is also presented. The availability of a physical testbed has brought a keener insight into the subtleties of the problem at hand.

Side Effects: Nausea and Vomiting

Cancer.gov

Types of nausea and vomiting caused by cancer treatment include: anticipatory, acute, and delayed. Controlling these side effects will help to prevent serious problems such as malnutrition and dehydration in people with cancer.

NASA aviation safety reporting system

NASA Technical Reports Server (NTRS)

1980-01-01

Knowledge of limitations of the Air Traffic Control system in conflict avoidance capabilities is discussed. Assumptions and expectations held by by airmen regarding the capabilities of the system are presented. Limitations related to communication are described and problems associated with visual approaches, airspace configurations, and airport layouts are discussed. A number of pilot and controller reports illustrative of three typical problem types: occurrences involving pilots who have limited experience; reports describing inflight calls for assistance; and flights in which pilots have declined to use available radar services are presented. Examples of Alert Bulletins and the FAA responses to them are included.

Flight investigation of cabin noise control treatments for a light turboprop aircraft

NASA Technical Reports Server (NTRS)

Wilby, J. F.; Oneal, R. L.; Mixson, J. S.

1985-01-01

The in-flight evaluation of noise control treatments for a light, twin-engined turboprop aircraft presents several problems associated with data analysis and interpretation. These problems include data repeatability, propeller synchronization, spatial distributions of the exterior pressure field and acoustic treatment, and the presence of flanking paths. They are discussed here with regard to a specific aeroplane configuration. Measurements were made in an untreated cabin and in a cabin fitted with an experimental sidewall treatment. Results are presented in terms of the insertion loss provided by the treatment and comparison made with predictions based on laboratory measurements.

Controlled Ecological Life Support System. Life Support Systems in Space Travel

NASA Technical Reports Server (NTRS)

Macelroy, R. D. (Editor); Smernoff, D. T. (Editor); Klein, H. P. (Editor)

1985-01-01

Life support systems in space travel, in closed ecological systems were studied. Topics discussed include: (1) problems of life support and the fundamental concepts of bioregeneration; (2) technology associated with physical/chemical regenerative life support; (3) projection of the break even points for various life support techniques; (4) problems of controlling a bioregenerative life support system; (5) data on the operation of an experimental algal/mouse life support system; (6) industrial concepts of bioregenerative life support; and (7) Japanese concepts of bioregenerative life support and associated biological experiments to be conducted in the space station.

A Corrosion Control Manual for Rail Rapid Transit

NASA Technical Reports Server (NTRS)

Gilbert, L. O.; Fitzgerald, J. H., III; Menke, J. T.; Lizak, R. M. (Editor)

1982-01-01

This manual addresses corrosion problems in the design, contruction, and maintenance of rapid transit systems. Design and maintenance solutions are provided for each problem covered. The scope encompasses all facilities of urban rapid transit systems: structures and tracks, platforms and stations, power and signals, and cars. The types of corrosion and their causes as well as rapid transit properties are described. Corrosion control committees, and NASA, DOD, and ASTM specifications and design criteria to which reference is made in the manual are listed. A bibliography of papers and excerpts of reports is provided and a glossary of frequently used terms is included.

Application of the Modular Command and Control Structure (MCES) to Marine Corps SINCGARS Allocation

DTIC Science & Technology

1991-07-01

The first goal is to delineate the difference between the system being analyzed and its environment . To bound the C3 system, the analyst should...hardware and software entities and structures, is related to the forces it controls and the environmental stimuli to which it responds, including the enemy...M CES represents the environmental facto:s that require explicit assumptions in the problem. This ring may be seen as including the major scenario

Research in Network Management Techniques for Tactical Data Communications Network.

DTIC Science & Technology

1982-09-01

the control period. Research areas include Packet Network modelling, adaptive network routing, network design algorithms, network design techniques...contro!lers are designed to perform their limited tasks optimally. For the dynamic routing problem considered here, the local controllers are node...feedback to finding in optimum stead-o-state routing (static strategies) under non - control which can be easily implemented in real time. congested

Adaptive tracking control of a wheeled mobile robot via an uncalibrated camera system.

PubMed

Dixon, W E; Dawson, D M; Zergeroglu, E; Behal, A

2001-01-01

This paper considers the problem of position/orientation tracking control of wheeled mobile robots via visual servoing in the presence of parametric uncertainty associated with the mechanical dynamics and the camera system. Specifically, we design an adaptive controller that compensates for uncertain camera and mechanical parameters and ensures global asymptotic position/orientation tracking. Simulation and experimental results are included to illustrate the performance of the control law.

Children born extremely preterm had different sleeping habits at 11 years of age and more childhood sleep problems than term-born children.

PubMed

Stangenes, Kristine Marie; Fevang, Silje Kathrine; Grundt, Jacob; Donkor, Hilde Mjell; Markestad, Trond; Hysing, Mari; Elgen, Irene Bircow; Bjorvatn, Bjørn

2017-12-01

This study explored whether extremely preterm (EPT) children had different sleep characteristics in childhood than children born at term and how neurodevelopmental disabilities (NDD) affected sleep in children born EPT. A Norwegian national cohort of 231 children born EPT from 1999 to 2000 and separate study data on 556 children born at term in 2001 were compared. Parental questionnaires mapped the children's current sleep habits at 11 years of age, namely the prevalence of sleep problems throughout childhood until this age and five categories of sleep problems. In addition, the EPT children were clinically assessed at five years of age. The EPT children had different sleep habits than the controls, for example they went to bed earlier. EPT children had a higher prevalence of sleep problems than the controls throughout childhood (26% versus 14%, p < 0.001) and this was also higher for the 93 EPT children with no NDD (20%) than for the controls (14%) and increased with increasing NDD to 67% (p = 0.015) for the six children with severe NDD. EPT children had different sleep habits to term-born controls at 11 years of age, including those with no NDD. The prevalence of sleep problems increased with increasing NDD. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Controlling Mold on Library Materials with Chlorine Dioxide: An Eight-Year Case Study.

ERIC Educational Resources Information Center

Weaver-Meyers, Pat L.; Kowaleski, Barbara; Stolt, Wilbur A.

1998-01-01

Discusses problems associated with mold growth at the University of Oklahoma libraries and describes the results of using chlorine dioxide in aqueous and gaseous forms. Highlights include toxicity compared to other preservation treatments; environmental controls; and explanations of a preference for the use of a self-activating gas packet.…

Air Traffic Control: Economics of Flight

NASA Technical Reports Server (NTRS)

Murphy, James R.

2004-01-01

Contents include the following: 1. Commercial flight is a partnership. Airlines. Pilots. Air traffic control. 2. Airline schedules and weather problems can cause delays at the airport. Delays are inevitable in de-regulated industry due to simple economics. 3.Delays can be mitigated. Build more runways/technology. Increase airspace supply. 4. Cost/benefit analysis determine justification.

A Randomized Controlled Trial of Pemoline for Attention-Deficit-hyperactivity Disorder in Substance-Abusing Adolescents

ERIC Educational Resources Information Center

Riggs, Paula D.; Hall, Shannon K.; Mikulich-Gilbertson, Susan K.; Lohman, Michelle; Kayser, Ashley

2004-01-01

Objective: In adolescents with substance use disorder (SUD), comorbid attention-deficit/hyperactivity disorder (ADHD) is associated with greater severity of substance abuse, conduct problems, and worse treatment outcomes. Although many controlled trials have established the efficacy of psychostimulants, including pemoline, for ADHD in children and…

Effect of routine assessment of specific psychosocial problems on personalized communication, counselors’ awareness, and distress levels in cancer genetic counseling practice: a randomized controlled trial.

PubMed

Eijzenga, Willem; Aaronson, Neil K; Hahn, Daniela E E; Sidharta, Grace N; van der Kolk, Lizet E; Velthuizen, Mary E; Ausems, Margreet G E M; Bleiker, Eveline M A

2014-09-20

This study evaluated the efficacy of a cancer genetics–specific questionnaire in facilitating communication about, awareness of, and management of psychosocial problems, as well as in lowering distress levels. Individuals referred to genetic counseling for cancer at two family cancer clinics in The Netherlands were randomly assigned to an intervention or a control group. All participants completed the psychosocial questionnaire before counseling. In the intervention group, the counselors received the results of this questionnaire before the counseling session. All sessions were audiotaped for content analysis. Primary outcomes were the frequency with which psychosocial problems were discussed, the genetic counselors’ awareness of these problems, and their management. Secondary outcomes included cancer worries and psychological distress, duration and dynamics of the counseling, and satisfaction. The frequency with which psychosocial problems were discussed with 246 participating counselees was significantly higher in the intervention group (n = 127) than in the control group (n =119; P = .004), as was the counselors’ awareness of psychosocial problems regarding hereditary predisposition (P < .001), living with cancer (P = .01), and general emotions (P < .001). Counselors initiated more discussion of psychosocial problems in the intervention group (P < .001), without affecting the length of the counseling session. No significant differences were found on management (P = .19). The intervention group reported significantly lower levels of cancer worries (p = .005) and distress (p = .02) after counseling. The routine assessment of psychosocial problems by questionnaire facilitates genetic counselors’ recognition and discussion of their clients’ psychosocial problems and reduces clients’ distress levels.

Execution of Multidisciplinary Design Optimization Approaches on Common Test Problems

NASA Technical Reports Server (NTRS)

Balling, R. J.; Wilkinson, C. A.

1997-01-01

A class of synthetic problems for testing multidisciplinary design optimization (MDO) approaches is presented. These test problems are easy to reproduce because all functions are given as closed-form mathematical expressions. They are constructed in such a way that the optimal value of all variables and the objective is unity. The test problems involve three disciplines and allow the user to specify the number of design variables, state variables, coupling functions, design constraints, controlling design constraints, and the strength of coupling. Several MDO approaches were executed on two sample synthetic test problems. These approaches included single-level optimization approaches, collaborative optimization approaches, and concurrent subspace optimization approaches. Execution results are presented, and the robustness and efficiency of these approaches an evaluated for these sample problems.

Analytic descriptions of stochastic bistable systems under force ramp

DOE PAGES

Friddle, Raymond W.

2016-05-13

Solving the two-state master equation with time-dependent rates, the ubiquitous driven bistable system, is a long-standing problem that does not permit a complete solution for all driving rates. We show an accurate approximation to this problem by considering the system in the control parameter regime. Moreover, the results are immediately applicable to a diverse range of bistable systems including single-molecule mechanics.

Discontinuous Galerkin Finite Element Method for Parabolic Problems

NASA Technical Reports Server (NTRS)

Kaneko, Hideaki; Bey, Kim S.; Hou, Gene J. W.

2004-01-01

In this paper, we develop a time and its corresponding spatial discretization scheme, based upon the assumption of a certain weak singularity of parallel ut(t) parallel Lz(omega) = parallel ut parallel2, for the discontinuous Galerkin finite element method for one-dimensional parabolic problems. Optimal convergence rates in both time and spatial variables are obtained. A discussion of automatic time-step control method is also included.

H∞ control for switched fuzzy systems via dynamic output feedback: Hybrid and switched approaches

NASA Astrophysics Data System (ADS)

Xiang, Weiming; Xiao, Jian; Iqbal, Muhammad Naveed

2013-06-01

Fuzzy T-S model has been proven to be a practical and effective way to deal with the analysis and synthesis problems for complex nonlinear systems. As for switched nonlinear system, describing its subsystems as fuzzy T-S models, namely switched fuzzy system, naturally is an alternative method to conventional control approaches. In this paper, the H∞ control problem for a class of switched fuzzy systems is addressed. Hybrid and switched design approaches are proposed with different availability of switching signal information at switching instant. The hybrid control strategy includes two parts: fuzzy controllers for subsystems and state updating controller at switching instant, and the switched control strategy contains the controllers for subsystems. It is demonstrated that the conservativeness is reduced by introducing the state updating behavior but its cost is an online prediction of switching signal. Numerical examples are given to illustrate the effectiveness of proposed approaches and compare the conservativeness of two approaches.

A mathematical problem and a Spacecraft Control Laboratory Experiment (SCOLE) used to evaluate control laws for flexible spacecraft. NASA/IEEE design challenge

NASA Technical Reports Server (NTRS)

Taylor, Lawrence W., Jr.; Balakrishnan, A. V.

1988-01-01

The problen of controlling large, flexible space systems has been evaluated using computer simulation. In several cases, ground experiments have also been used to validate system performance under more realistic conditions. There remains a need, however, to test additional control laws for flexible spacecraft and to directly compare competing design techniques. A program is discussed which has been initiated to make direct comparisons of control laws for, first, a mathematical problem, then and experimental test article being assembled under the cognizance of the Spacecraft Control Branch at the NASA Langley Research Center with the advice and counsel of the IEEE Subcommittee on Large Space Structures. The physical apparatus will consist of a softly supported dynamic model of an antenna attached to the Shuttle by a flexible beam. The control objective will include the task of directing the line-of-sight of the Shuttle antenna configuration toward a fixed target, under conditions of noisy data, control authority and random disturbances.

Bt maize and integrated pest management--a European perspective.

PubMed

Meissle, Michael; Romeis, Jörg; Bigler, Franz

2011-09-01

The European corn borer (Ostrinia nubilalis), the Mediterranean corn borer (Sesamia nonagrioides) and the western corn rootworm (Diabrotica virgifera virgifera) are the main arthropod pests in European maize production. Practised pest control includes chemical control, biological control and cultural control such as ploughing and crop rotation. A pest control option that is available since 1996 is maize varieties that are genetically engineered (GE) to produce insecticidal compounds. GE maize varieties available today express one or several genes from Bacillus thuringiensis (Bt) that target corn borers or corn rootworms. Incentives to growing Bt maize are simplified farm operations, high pest control efficiency, improved grain quality and ecological benefits. Limitations include the risk of resistance evolution in target pest populations, risk of secondary pest outbreaks and increased administration to comply with licence agreements. Growers willing to plant Bt maize in the European Union (EU) often face the problem that authorisation is denied. Only one Bt maize transformation event (MON810) is currently authorised for commercial cultivation, and some national authorities have banned cultivation. Spain is the only EU member state where Bt maize adoption levels are currently delivering farm income gains near full potential levels. In an integrated pest management (IPM) context, Bt maize can be regarded as a preventive (host plant resistance) or a responsive pest control measure. In any case, Bt maize is a highly specific tool that efficiently controls the main pests and allows combination with other preventive or responsive measures to solve other agricultural problems including those with secondary pests. Copyright © 2011 Society of Chemical Industry.

A parameter optimization approach to controller partitioning for integrated flight/propulsion control application

NASA Technical Reports Server (NTRS)

Schmidt, Phillip; Garg, Sanjay; Holowecky, Brian

1992-01-01

A parameter optimization framework is presented to solve the problem of partitioning a centralized controller into a decentralized hierarchical structure suitable for integrated flight/propulsion control implementation. The controller partitioning problem is briefly discussed and a cost function to be minimized is formulated, such that the resulting 'optimal' partitioned subsystem controllers will closely match the performance (including robustness) properties of the closed-loop system with the centralized controller while maintaining the desired controller partitioning structure. The cost function is written in terms of parameters in a state-space representation of the partitioned sub-controllers. Analytical expressions are obtained for the gradient of this cost function with respect to parameters, and an optimization algorithm is developed using modern computer-aided control design and analysis software. The capabilities of the algorithm are demonstrated by application to partitioned integrated flight/propulsion control design for a modern fighter aircraft in the short approach to landing task. The partitioning optimization is shown to lead to reduced-order subcontrollers that match the closed-loop command tracking and decoupling performance achieved by a high-order centralized controller.

A parameter optimization approach to controller partitioning for integrated flight/propulsion control application

NASA Technical Reports Server (NTRS)

Schmidt, Phillip H.; Garg, Sanjay; Holowecky, Brian R.

1993-01-01

A parameter optimization framework is presented to solve the problem of partitioning a centralized controller into a decentralized hierarchical structure suitable for integrated flight/propulsion control implementation. The controller partitioning problem is briefly discussed and a cost function to be minimized is formulated, such that the resulting 'optimal' partitioned subsystem controllers will closely match the performance (including robustness) properties of the closed-loop system with the centralized controller while maintaining the desired controller partitioning structure. The cost function is written in terms of parameters in a state-space representation of the partitioned sub-controllers. Analytical expressions are obtained for the gradient of this cost function with respect to parameters, and an optimization algorithm is developed using modern computer-aided control design and analysis software. The capabilities of the algorithm are demonstrated by application to partitioned integrated flight/propulsion control design for a modern fighter aircraft in the short approach to landing task. The partitioning optimization is shown to lead to reduced-order subcontrollers that match the closed-loop command tracking and decoupling performance achieved by a high-order centralized controller.

Testing Alternative Explanations for the Associations Between Parenting and Adolescent Suicidal Problems

PubMed Central

Boeninger, Daria K.; Masyn, Katherine E.; Conger, Rand D.

2012-01-01

Although studies have established associations between parenting characteristics and adolescent suicidality, the strength of the evidence for these links remains unclear, largely because of methodological limitations, including lack of accounting for possible child effects on parenting. This study addresses these issues by using autoregressive cross-lag models with data on 802 adolescents and their parents across 5 years. Observed parenting behaviors predicted change in adolescent suicidal problems across one-year intervals even after controlling for adolescents’ effects on parenting. Nurturant-involved parenting continued to demonstrate salutary effects after controlling for adolescent and parent internalizing psychopathology: over time, observed nurturant-involved parenting reduced the likelihood of adolescent suicidal problems. This study increases the empirical support implicating parenting behaviors in the developmental course of adolescent suicidality. PMID:24244079

The intergenerational transmission of problem gambling: The mediating role of offspring gambling expectancies and motives.

PubMed

Dowling, N A; Oldenhof, E; Shandley, K; Youssef, G J; Vasiliadis, S; Thomas, S A; Frydenberg, E; Jackson, A C

2018-02-01

The risk for developing a gambling problem is greater among offspring who have a problem gambling parent, yet little research has directly examined the mechanisms by which this transmission of problem gambling occurs. For this reason, the present study sought to examine the degree to which children's expectancies and motives relating to gambling explain, at least in part, the intergenerational transmission of problem gambling. Participants (N=524; 56.5% male) were recruited from educational institutions, and retrospectively reported on parental problem gambling. Problem gambling was measured using the Problem Gambling Severity Index and a range of positive and negative expectancies and gambling motives were explored as potential mediators of the relationship between parent-and-participant problem gambling. The relationship between parent-and-participant problem gambling was significant, and remained so after controlling for sociodemographic factors and administration method. Significant mediators of this relationship included self-enhancement expectancies (feeling in control), money expectancies (financial gain), over-involvement (preoccupation with gambling) and emotional impact expectancies (guilt, shame, and loss), as well as enhancement motives (gambling to increase positive feelings) and coping motives (gambling to reduce or avoid negative emotions). All mediators remained significant when entered into the same model. The findings highlight that gambling expectancies and motives present unique pathways to the development of problem gambling in the offspring of problem gambling parents, and suggest that gambling cognitions may be potential candidates for targeted interventions for the offspring of problem gamblers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Space construction base control system

NASA Technical Reports Server (NTRS)

1978-01-01

Aspects of an attitude control system were studied and developed for a large space base that is structurally flexible and whose mass properties change rather dramatically during its orbital lifetime. Topics of discussion include the following: (1) space base orbital pointing and maneuvering; (2) angular momentum sizing of actuators; (3) momentum desaturation selection and sizing; (4) multilevel control technique applied to configuration one; (5) one-dimensional model simulation; (6) N-body discrete coordinate simulation; (7) structural analysis math model formulation; and (8) discussion of control problems and control methods.

Type-2 fuzzy logic control of a 2-DOF helicopter (TRMS system)

NASA Astrophysics Data System (ADS)

Zeghlache, Samir; Kara, Kamel; Saigaa, Djamel

2014-09-01

The helicopter dynamic includes nonlinearities, parametric uncertainties and is subject to unknown external disturbances. Such complicated dynamics involve designing sophisticated control algorithms that can deal with these difficulties. In this paper, a type 2 fuzzy logic PID controller is proposed for TRMS (twin rotor mimo system) control problem. Using triangular membership functions and based on a human operator experience, two controllers are designed to control the position of the yaw and the pitch angles of the TRMS. Simulation results are given to illustrate the effectiveness of the proposed control scheme.

Proceedings of the American Medical Association Congress on Environmental Health Problems (1st, Chicago, Illinois, May 1-2, 1964).

ERIC Educational Resources Information Center

American Medical Association, Chicago, IL.

Included are the proceedings of the first Congress on Environmental Health. Topics related to air pollution include the extent of human exposure, its relation to disease, evaluating effects clinically, community control and the physician's role. Topics related to pesticides include treatment of poisonings, occurrence of poisonings, safe usage, and…

Occupational Health for Health Care Providers

MedlinePlus

Health care workers are exposed to many job hazards. These can include Infections Needle injuries Back injuries ... prevention practices. They can reduce your risk of health problems. Use protective equipment, follow infection control guidelines, ...

Reflections on Higher Education

ERIC Educational Resources Information Center

Fleming, R. W.

1975-01-01

Four problems of higher education are discussed. These include the relationship between society's manpower needs and educational policy; egalitarian admission policies and faculty workloads; government control of monetary appropriations; and economic viability of the institution. (DE)

Multimode ergometer system

NASA Technical Reports Server (NTRS)

Bynum, B. G.; Gause, R. L.; Spier, R. A.

1971-01-01

System overcomes previous ergometer design and calibration problems including inaccurate measurements, large weight, size, and input power requirements, poor heat dissipation, high flammability, and inaccurate calibration. Device consists of lightweight, accurately controlled ergometer, restraint system, and calibration system.

State-dependent differential Riccati equation to track control of time-varying systems with state and control nonlinearities.

PubMed

Korayem, M H; Nekoo, S R

2015-07-01

This work studies an optimal control problem using the state-dependent Riccati equation (SDRE) in differential form to track for time-varying systems with state and control nonlinearities. The trajectory tracking structure provides two nonlinear differential equations: the state-dependent differential Riccati equation (SDDRE) and the feed-forward differential equation. The independence of the governing equations and stability of the controller are proven along the trajectory using the Lyapunov approach. Backward integration (BI) is capable of solving the equations as a numerical solution; however, the forward solution methods require the closed-form solution to fulfill the task. A closed-form solution is introduced for SDDRE, but the feed-forward differential equation has not yet been obtained. Different ways of solving the problem are expressed and analyzed. These include BI, closed-form solution with corrective assumption, approximate solution, and forward integration. Application of the tracking problem is investigated to control robotic manipulators possessing rigid or flexible joints. The intention is to release a general program for automatic implementation of an SDDRE controller for any manipulator that obeys the Denavit-Hartenberg (D-H) principle when only D-H parameters are received as input data. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Robust pinning control of heterogeneous complex networks with jointly connected topologies and time-varying parametric uncertainty

NASA Astrophysics Data System (ADS)

Manfredi, Sabato

2018-05-01

The pinning/leader control problems provide the design of the leader or pinning controller in order to guide a complex network to a desired trajectory or target (synchronisation or consensus). Let a time-invariant complex network, pinning/leader control problems include the design of the leader or pinning controller gain and number of nodes to pin in order to guide a network to a desired trajectory (synchronization or consensus). Usually, lower is the number of pinned nodes larger is the pinning gain required to assess network synchronisation. On the other side, realistic application scenario of complex networks is characterised by switching topologies, time-varying node coupling strength and link weight that make hard to solve the pinning/leader control problem. Additionally, the system dynamics at nodes can be heterogeneous. In this paper, we derive robust stabilisation conditions of time-varying heterogeneous complex networks with jointly connected topologies when coupling strength and link weight interactions are affected by time-varying uncertainties. By employing Lyapunov stability theory and linear matrix inequality (LMI) technique, we formulate low computationally demanding stabilisability conditions to design a pinning/leader control gain for robust network synchronisation. The effectiveness of the proposed approach is shown by several design examples applied to a paradigmatic well-known complex network composed of heterogeneous Chua's circuits.

Self-Organizing Hierarchical Particle Swarm Optimization with Time-Varying Acceleration Coefficients for Economic Dispatch with Valve Point Effects and Multifuel Options

NASA Astrophysics Data System (ADS)

Polprasert, Jirawadee; Ongsakul, Weerakorn; Dieu, Vo Ngoc

2011-06-01

This paper proposes a self-organizing hierarchical particle swarm optimization (SPSO) with time-varying acceleration coefficients (TVAC) for solving economic dispatch (ED) problem with non-smooth functions including multiple fuel options (MFO) and valve-point loading effects (VPLE). The proposed SPSO with TVAC is the new approach optimizer and good performance for solving ED problems. It can handle the premature convergence of the problem by re-initialization of velocity whenever particles are stagnated in the search space. To properly control both local and global explorations of the swarm during the optimization process, the performance of TVAC is included. The proposed method is tested in different ED problems with non-smooth cost functions and the obtained results are compared to those from many other methods in the literature. The results have revealed that the proposed SPSO with TVAC is effective in finding higher quality solutions for non-smooth ED problems than many other methods.

Optimality of affine control system of several species in competition on a sequential batch reactor

NASA Astrophysics Data System (ADS)

Rodríguez, J. C.; Ramírez, H.; Gajardo, P.; Rapaport, A.

2014-09-01

In this paper, we analyse the optimality of affine control system of several species in competition for a single substrate on a sequential batch reactor, with the objective being to reach a given (low) level of the substrate. We allow controls to be bounded measurable functions of time plus possible impulses. A suitable modification of the dynamics leads to a slightly different optimal control problem, without impulsive controls, for which we apply different optimality conditions derived from Pontryagin principle and the Hamilton-Jacobi-Bellman equation. We thus characterise the singular trajectories of our problem as the extremal trajectories keeping the substrate at a constant level. We also establish conditions for which an immediate one impulse (IOI) strategy is optimal. Some numerical experiences are then included in order to illustrate our study and show that those conditions are also necessary to ensure the optimality of the IOI strategy.

A boundedness result for the direct heuristic dynamic programming.

PubMed

Liu, Feng; Sun, Jian; Si, Jennie; Guo, Wentao; Mei, Shengwei

2012-08-01

Approximate/adaptive dynamic programming (ADP) has been studied extensively in recent years for its potential scalability to solve large state and control space problems, including those involving continuous states and continuous controls. The applicability of ADP algorithms, especially the adaptive critic designs has been demonstrated in several case studies. Direct heuristic dynamic programming (direct HDP) is one of the ADP algorithms inspired by the adaptive critic designs. It has been shown applicable to industrial scale, realistic and complex control problems. In this paper, we provide a uniformly ultimately boundedness (UUB) result for the direct HDP learning controller under mild and intuitive conditions. By using a Lyapunov approach we show that the estimation errors of the learning parameters or the weights in the action and critic networks remain UUB. This result provides a useful controller convergence guarantee for the first time for the direct HDP design. Copyright © 2012 Elsevier Ltd. All rights reserved.

Moderators and mediators of the effects of interparental conflict on children's adjustment.

PubMed

Kerig, P K

1998-06-01

Moderational and mediational models of the relationships among appraisals, interparental conflict, and children's adjustment were tested in a sample of 174 families with a school-age child. Parents rated children's exposure to interparental conflict and internalizing, externalizing, and total behavior problems. Children completed questionnaires regarding their appraisals of their parents' conflicts, including frequency and intensity, perceived threat, control, and self-blame, as well as measures of anxiety and depression. Results overall demonstrated more consistent support for the moderational than mediational hypotheses. Appraisals of conflict properties, threat, self-blame, and perceived control moderated the effects of interparental conflict on externalizing, total problems, and anxiety in boys. Conflict properties, threat, self-blame, perceived control, and self-calming acted as moderators of internalizing in girls.

Simulation of flexible appendage interactions with Mariner Venus/Mercury attitude control and science platform pointing

NASA Technical Reports Server (NTRS)

Fleischer, G. E.

1973-01-01

A new computer subroutine, which solves the attitude equations of motion for any vehicle idealized as a topological tree of hinge-connected rigid bodies, is used to simulate and analyze science instrument pointing control interaction with a flexible Mariner Venus/Mercury (MVM) spacecraft. The subroutine's user options include linearized or partially linearized hinge-connected models whose computational advantages are demonstrated for the MVM problem. Results of the pointing control/flexible vehicle interaction simulations, including imaging experiment pointing accuracy predictions and implications for MVM science sequence planning, are described in detail.

Water reuse systems: A review of the principal components

USGS Publications Warehouse

Lucchetti, G.; Gray, G.A.

1988-01-01

Principal components of water reuse systems include ammonia removal, disease control, temperature control, aeration, and particulate filtration. Effective ammonia removal techniques include air stripping, ion exchange, and biofiltration. Selection of a particular technique largely depends on site-specific requirements (e.g., space, existing water quality, and fish densities). Disease control, although often overlooked, is a major problem in reuse systems. Pathogens can be controlled most effectively with ultraviolet radiation, ozone, or chlorine. Simple and inexpensive methods are available to increase oxygen concentration and eliminate gas supersaturation, these include commercial aerators, air injectors, and packed columns. Temperature control is a major advantage of reuse systems, but the equipment required can be expensive, particularly if water temperature must be rigidly controlled and ambient air temperature fluctuates. Filtration can be readily accomplished with a hydrocyclone or sand filter that increases overall system efficiency. Based on criteria of adaptability, efficiency, and reasonable cost, we recommend components for a small water reuse system.

Mixed H∞ and passive control for linear switched systems via hybrid control approach

NASA Astrophysics Data System (ADS)

Zheng, Qunxian; Ling, Youzhu; Wei, Lisheng; Zhang, Hongbin

2018-03-01

This paper investigates the mixed H∞ and passive control problem for linear switched systems based on a hybrid control strategy. To solve this problem, first, a new performance index is proposed. This performance index can be viewed as the mixed weighted H∞ and passivity performance. Then, the hybrid controllers are used to stabilise the switched systems. The hybrid controllers consist of dynamic output-feedback controllers for every subsystem and state updating controllers at the switching instant. The design of state updating controllers not only depends on the pre-switching subsystem and the post-switching subsystem, but also depends on the measurable output signal. The hybrid controllers proposed in this paper can include some existing ones as special cases. Combine the multiple Lyapunov functions approach with the average dwell time technique, new sufficient conditions are obtained. Under the new conditions, the closed-loop linear switched systems are globally uniformly asymptotically stable with a mixed H∞ and passivity performance index. Moreover, the desired hybrid controllers can be constructed by solving a set of linear matrix inequalities. Finally, a numerical example and a practical example are given.

Implementation of effective alcohol control strategies is needed at large sports and entertainment events.

PubMed

Lyne, Mark; Galloway, Andrew

2012-02-01

To assess the implementation and effectiveness of strategies and actions to eliminate and/or reduce alcohol-related problems at large sports and entertainment events in New Zealand. We conducted site visits and monitoring observations at venues before, during and after a variety of large events between March 2009 and November 2010. Thirteen events were attended at nine different venues. Events included rugby, rugby league and cricket matches, motor racing, rowing, horse racing, an outdoor music festival, and food and wine festivals. Most large events appeared to pass with few or no alcohol-related problems. The exceptions were one of the horse-race meetings, a rugby league match and one food and wine festival. Common contexts at events where alcohol-related problems were seen included: inadequate alcohol control and management by security staff; the ability to purchase four alcoholic drinks (rather than two) at a time; inexperienced bar staff untrained in responsible alcohol service; no or little promotion of low and non-alcoholic drinks; and a lack of monitoring and enforcement of the law on intoxication. An important approach to prevent and reduce alcohol-related problems at large spots and entertainment events is the use of specific alcohol-control strategies. The management of alcohol consumption is a major part of event management that must be planned with harm-minimisation strategies well in advance of the event itself. If strategies and actions are not properly implemented to manage the sale and supply of alcohol at large events, there is significant risk of alcohol-related problems and harm resulting from them. © 2012 The Authors. ANZJPH © 2012 Public Health Association of Australia.

Population and development problems: a critical assessment of conventional wisdom. The case of Zimbabwe.

PubMed

Sibanda, A E

1988-01-01

Conventional wisdom, as reflected in reports by the World Bank and the Whitsun Foundation, maintains that control of population growth is the key strategy for stimulating socioeconomic development and ending widespread poverty. The Witsun Foundation has criticized the Government of Zimbabwe for failing to include specific policies for population control in its National Transitional Development Plan. the report further expressed alarm about future availability of land to contain Zimbabwe's growing population. Communal areas are designed for a maximum of 325,000 families yet presently contain 700-800,000 families. This Malthusian, deterministic emphasis on population growth as the source of social ills ignores the broader, complex set of socioeconomic, historical, and political factors that determine material life. Any analysis of population that fails to consider the class structure of society, the type of division of labor, and forms of property and production can produce only meaningless abstractions. For example, consideration of crowding in communal areas must include consideration of inequitable patterns of land ownership in sub-Saharan Africa. Unemployment must be viewed within the context of a capitalist economic structure that relies on an industrial reserve army of labor to ensure acceptance of low wages and labor-intensive conditions. While it is accepted that population growth is creating specific and real problems in Zimbabwe and other African countries, these problems could be ameliorated by land reform and restructuring of the export-oriented colonial economies. Similarly, birth control should not be promoted as the solution to social problems, yet family planning services should be available to raise the status of women. Literacy, agrarian reform, agricultural modernization, and industrialization campaigns free from the dominance of Western capitalism represent the true solutions to Zimbabwe's problems.

Aerospace Applications of Integer and Combinatorial Optimization

NASA Technical Reports Server (NTRS)

Padula, S. L.; Kincaid, R. K.

1995-01-01

Research supported by NASA Langley Research Center includes many applications of aerospace design optimization and is conducted by teams of applied mathematicians and aerospace engineers. This paper investigates the benefits from this combined expertise in formulating and solving integer and combinatorial optimization problems. Applications range from the design of large space antennas to interior noise control. A typical problem, for example, seeks the optimal locations for vibration-damping devices on an orbiting platform and is expressed as a mixed/integer linear programming problem with more than 1500 design variables.

Aerospace applications on integer and combinatorial optimization

NASA Technical Reports Server (NTRS)

Padula, S. L.; Kincaid, R. K.

1995-01-01

Research supported by NASA Langley Research Center includes many applications of aerospace design optimization and is conducted by teams of applied mathematicians and aerospace engineers. This paper investigates the benefits from this combined expertise in formulating and solving integer and combinatorial optimization problems. Applications range from the design of large space antennas to interior noise control. A typical problem. for example, seeks the optimal locations for vibration-damping devices on an orbiting platform and is expressed as a mixed/integer linear programming problem with more than 1500 design variables.

Skylab-EREP studies in computer mapping of terrain in the Cripple Creek-Canon City area of Colorado

NASA Technical Reports Server (NTRS)

Smedes, H. W.; Ranson, K. J.; Holstrom, R. L.

1975-01-01

Multispectral-scanner data from satellites are used as input to computers for automatically mapping terrain classes of ground cover. Some major problems faced in this remote-sensing task include: (1) the effect of mixtures of classes and, primarily because of mixtures, the problem of what constitutes accurate control data, and (2) effects of the atmosphere on spectral responses. The fundamental principles of these problems are presented along with results of studies of them for a test site of Colorado, using LANDSAT-1 data.

Integrated controls-structures design methodology development for a class of flexible spacecraft

NASA Technical Reports Server (NTRS)

Maghami, P. G.; Joshi, S. M.; Walz, J. E.; Armstrong, E. S.

1990-01-01

Future utilization of space will require large space structures in low-Earth and geostationary orbits. Example missions include: Earth observation systems, personal communication systems, space science missions, space processing facilities, etc., requiring large antennas, platforms, and solar arrays. The dimensions of such structures will range from a few meters to possibly hundreds of meters. For reducing the cost of construction, launching, and operating (e.g., energy required for reboosting and control), it will be necessary to make the structure as light as possible. However, reducing structural mass tends to increase the flexibility which would make it more difficult to control with the specified precision in attitude and shape. Therefore, there is a need to develop a methodology for designing space structures which are optimal with respect to both structural design and control design. In the current spacecraft design practice, it is customary to first perform the structural design and then the controller design. However, the structural design and the control design problems are substantially coupled and must be considered concurrently in order to obtain a truly optimal spacecraft design. For example, let C denote the set of the 'control' design variables (e.g., controller gains), and L the set of the 'structural' design variables (e.g., member sizes). If a structural member thickness is changed, the dynamics would change which would then change the control law and the actuator mass. That would, in turn, change the structural model. Thus, the sets C and L depend on each other. Future space structures can be roughly divided into four mission classes. Class 1 missions include flexible spacecraft with no articulated appendages which require fine attitude pointing and vibration suppression (e.g., large space antennas). Class 2 missions consist of flexible spacecraft with articulated multiple payloads, where the requirement is to fine-point the spacecraft and each individual payload while suppressing the elastic motion. Class 3 missions include rapid slewing of spacecraft without appendages, while Class 4 missions include general nonlinear motion of a flexible spacecraft with articulated appendages and robot arms. Class 1 and 2 missions represent linear mathematical modeling and control system design problems (except for actuator and sensor nonlinearities), while Class 3 and 4 missions represent nonlinear problems. The development of an integrated controls/structures design approach for Class 1 missions is addressed. The performance for these missions is usually specified in terms of (1) root mean square (RMS) pointing errors at different locations on the structure, and (2) the rate of decay of the transient response. Both of these performance measures include the contributions of rigid as well as elastic motion.

Relations between problem behaviors, perceived symptom severity and parenting in adolescents and emerging adults with ASD: The mediating role of parental psychological need frustration.

PubMed

Dieleman, Lisa M; De Pauw, Sarah S W; Soenens, Bart; Mabbe, Elien; Campbell, Rachel; Prinzie, Peter

2018-02-01

Research in parents of youngsters with Autism Spectrum Disorder (ASD) increasingly documents associations between children's problem behaviors and symptom severity and more dysfunctional and less adaptive parenting behaviors. However, the mechanisms underlying these associations have not been examined thoroughly. This study examines the mediating role of parental need frustration in the relation between child maladjustment (i.e., problem behavior and autism severity) and parenting behavior (i.e., controlling and autonomy-supportive parenting). The sample included 95 parents of adolescents/emerging adults with ASD (M age =18.8years, SD=2.3). Parents completed questionnaires assessing their parenting strategies and psychological need frustration as well as the internalizing and externalizing problem behaviors and autism severity of their child. Results indicate that the association between externalizing problems and controlling parenting was partially mediated by need frustration. This suggests that externalizing problems go together with lower feelings of parent-child closeness, lower parental competence, and a decreased sense of volitional functioning, feelings that, in turn, relate to more controlling strategies. Symptom severity has a direct negative association with autonomy support, suggesting that parents lower their autonomy support when their child has high levels of autism symptoms, without experiencing these symptoms as a threat to their own psychological needs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aircraft digital flight control technical review

NASA Technical Reports Server (NTRS)

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.

Calibrating and adjusting expectations in life: A grounded theory on how elderly persons with somatic health problems maintain control and balance in life and optimize well-being

PubMed Central

Helvik, Anne-Sofie; Iversen, Valentina Cabral; Steiring, Randi; Hallberg, Lillemor R-M

2011-01-01

Aim This study aims at exploring the main concern for elderly individuals with somatic health problems and what they do to manage this. Method In total, 14 individuals (mean=74.2 years; range=68–86 years) of both gender including hospitalized and outpatient persons participated in the study. Open interviews were conducted and analyzed according to grounded theory, an inductive theory-generating method. Results The main concern for the elderly individuals with somatic health problems was identified as their striving to maintain control and balance in life. The analysis ended up in a substantive theory explaining how elderly individuals with somatic disease were calibrating and adjusting their expectations in life in order to adapt to their reduced energy level, health problems, and aging. By adjusting the expectations to their actual abilities, the elderly can maintain a sense of that they still have the control over their lives and create stability. The ongoing adjustment process is facilitated by different strategies and result despite lower expectations in subjective well-being. The facilitating strategies are utilizing the network of important others, enjoying cultural heritage, being occupied with interests, having a mission to fulfill, improving the situation by limiting boundaries and, finally, creating meaning in everyday life. Conclusion The main concern of the elderly with somatic health problems was to maintain control and balance in life. The emerging theory explains how elderly people with somatic health problems calibrate their expectations of life in order to adjust to reduced energy, health problems, and aging. This process is facilitated by different strategies and result despite lower expectation in subjective well-being. PMID:21468299

Promoting Students' Problem Solving Skills and Knowledge of STEM Concepts in a Data-Rich Learning Environment: Using Online Data as a Tool for Teaching about Renewable Energy Technologies

NASA Astrophysics Data System (ADS)

Thurmond, Brandi

This study sought to compare a data-rich learning (DRL) environment that utilized online data as a tool for teaching about renewable energy technologies (RET) to a lecture-based learning environment to determine the impact of the learning environment on students' knowledge of Science, Technology, Engineering, and Math (STEM) concepts related to renewable energy technologies and students' problem solving skills. Two purposefully selected Advanced Placement (AP) Environmental Science teachers were included in the study. Each teacher taught one class about RET in a lecture-based environment (control) and another class in a DRL environment (treatment), for a total of four classes of students (n=128). This study utilized a quasi-experimental, pretest/posttest, control-group design. The initial hypothesis that the treatment group would have a significant gain in knowledge of STEM concepts related to RET and be better able to solve problems when compared to the control group was not supported by the data. Although students in the DRL environment had a significant gain in knowledge after instruction, posttest score comparisons of the control and treatment groups revealed no significant differences between the groups. Further, no significant differences were noted in students' problem solving abilities as measured by scores on a problem-based activity and self-reported abilities on a reflective questionnaire. This suggests that the DRL environment is at least as effective as the lecture-based learning environment in teaching AP Environmental Science students about RET and fostering the development of problem solving skills. As this was a small scale study, further research is needed to provide information about effectiveness of DRL environments in promoting students' knowledge of STEM concepts and problem-solving skills.

Lee Silverman Voice Treatment versus standard speech and language therapy versus control in Parkinson's disease: a pilot randomised controlled trial (PD COMM pilot).

PubMed

Sackley, Catherine M; Smith, Christina H; Rick, Caroline E; Brady, Marian C; Ives, Natalie; Patel, Smitaa; Woolley, Rebecca; Dowling, Francis; Patel, Ramilla; Roberts, Helen; Jowett, Sue; Wheatley, Keith; Kelly, Debbie; Sands, Gina; Clarke, Carl E

2018-01-01

Speech-related problems are common in Parkinson's disease (PD), but there is little evidence for the effectiveness of standard speech and language therapy (SLT) or Lee Silverman Voice Treatment (LSVT LOUD®). The PD COMM pilot was a three-arm, assessor-blinded, randomised controlled trial (RCT) of LSVT LOUD®, SLT and no intervention (1:1:1 ratio) to assess the feasibility and to inform the design of a full-scale RCT. Non-demented patients with idiopathic PD and speech problems and no SLT for speech problems in the past 2 years were eligible. LSVT LOUD® is a standardised regime (16 sessions over 4 weeks). SLT comprised individualised content per local practice (typically weekly sessions for 6-8 weeks). Outcomes included recruitment and retention, treatment adherence, and data completeness. Outcome data collected at baseline, 3, 6, and 12 months included patient-reported voice and quality of life measures, resource use, and assessor-rated speech recordings. Eighty-nine patients were randomised with 90% in the therapy groups and 100% in the control group completing the trial. The response rate for Voice Handicap Index (VHI) in each arm was ≥ 90% at all time-points. VHI was highly correlated with the other speech-related outcome measures. There was a trend to improvement in VHI with LSVT LOUD® (difference at 3 months compared with control: - 12.5 points; 95% CI - 26.2, 1.2) and SLT (difference at 3 months compared with control: - 9.8 points; 95% CI - 23.2, 3.7) which needs to be confirmed in an adequately powered trial. Randomisation to a three-arm trial of speech therapy including a no intervention control is feasible and acceptable. Compliance with both interventions was good. VHI and other patient-reported outcomes were relevant measures and provided data to inform the sample size for a substantive trial. International Standard Randomised Controlled Trial Number Register: ISRCTN75223808. registered 22 March 2012.

Much ado about aha!: Insight problem solving is strongly related to working memory capacity and reasoning ability.

PubMed

Chuderski, Adam; Jastrzębski, Jan

2018-02-01

A battery comprising 4 fluid reasoning tests as well as 13 working memory (WM) tasks that involved storage, recall, updating, binding, and executive control, was applied to 318 adults in order to evaluate the true relationship of reasoning ability and WM capacity (WMC) to insight problem solving, measured using 40 verbal, spatial, math, matchstick, and remote associates problems (insight problems). WMC predicted 51.8% of variance in insight problem solving and virtually explained its almost isomorphic link to reasoning ability (84.6% of shared variance). The strong link between WMC and insight pertained generally to most WM tasks and insight problems, was identical for problems solved with and without reported insight, was linear throughout the ability levels, and was not mediated by age, motivation, anxiety, psychoticism, and openness to experience. In contrast to popular views on the sudden and holistic nature of insight, the solving of insight problems results primarily from typical operations carried out by the basic WM mechanisms that are responsible for the maintenance, retrieval, transformation, and control of information in the broad range of intellectual tasks (including fluid reasoning). Little above and beyond WM is unique about insight. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Efficient algorithms for a class of partitioning problems

NASA Technical Reports Server (NTRS)

Iqbal, M. Ashraf; Bokhari, Shahid H.

1990-01-01

The problem of optimally partitioning the modules of chain- or tree-like tasks over chain-structured or host-satellite multiple computer systems is addressed. This important class of problems includes many signal processing and industrial control applications. Prior research has resulted in a succession of faster exact and approximate algorithms for these problems. Polynomial exact and approximate algorithms are described for this class that are better than any of the previously reported algorithms. The approach is based on a preprocessing step that condenses the given chain or tree structured task into a monotonic chain or tree. The partitioning of this monotonic take can then be carried out using fast search techniques.

The efficacy of a standardized questionnaire in facilitating personalized communication about problems encountered in cancer genetic counseling: design of a randomized controlled trial

PubMed Central

2014-01-01

Background Individuals with a personal or family history of cancer, can opt for genetic counseling and DNA-testing. Approximately 25% of these individuals experience clinically relevant levels of psychosocial distress, depression and/or anxiety after counseling. These problems are frequently left undetected by genetic counselors. The aim of this study is to evaluate the efficacy of a cancer genetics-specific screening questionnaire for psychosocial problems, the ‘Psychosocial Aspects of Hereditary Cancer (PAHC) questionnaire’ together with the Distress Thermometer, in: (1) facilitating personalized counselor-counselee communication; (2) increasing counselors’ awareness of their counselees’ psychosocial problems; and (3) facilitating the management of psychosocial problems during and after genetic counseling. Methods This multicenter, randomized controlled trial will include 264 individuals undergoing cancer genetic counseling in two family cancer clinics in the Netherlands. Participants will be randomized to either: (1) an intervention group that completes the PAHC questionnaire, the results of which are made available to the genetic counselor prior to the counseling session; or (2) a control group that completes the PAHC questionnaire, but without feedback being given to the genetic counselor. The genetic counseling sessions will be audiotaped for content analysis. Additionally, study participants will be asked to complete questionnaires at baseline, three weeks after the initial counseling session, and four months after a telephone follow-up counseling session. The genetic counselors will be asked to complete questionnaires at the start of and at completion of the study, as well as a checklist directly after each counseling session. The questionnaires/checklists of the study include items on communication during genetic counseling, counselor awareness of their clients’ psychosocial problems, the (perceived) need for professional psychosocial support, cancer worries, general distress, specific psychosocial problems, satisfaction with care received, and experience using the PAHC questionnaire. Discussion This study will provide empirical evidence regarding the efficacy of a relatively brief psychosocial screening questionnaire in terms of facilitating personalized communication, increasing counselors’ awareness, and optimizing management of psychosocial problems in the cancer genetic counseling setting. Trial registration This study is registered at the Netherlands Trial Register (NTR3205) and ClinicalTrials.gov (NCT01562431). PMID:24428912

The efficacy of a standardized questionnaire in facilitating personalized communication about problems encountered in cancer genetic counseling: design of a randomized controlled trial.

PubMed

Eijzenga, Willem; Aaronson, Neil K; Kluijt, Irma; Sidharta, Grace N; Hahn, Daniela Ee; Ausems, Margreet Gem; Bleiker, Eveline Ma

2014-01-15

Individuals with a personal or family history of cancer, can opt for genetic counseling and DNA-testing. Approximately 25% of these individuals experience clinically relevant levels of psychosocial distress, depression and/or anxiety after counseling. These problems are frequently left undetected by genetic counselors. The aim of this study is to evaluate the efficacy of a cancer genetics-specific screening questionnaire for psychosocial problems, the 'Psychosocial Aspects of Hereditary Cancer (PAHC) questionnaire' together with the Distress Thermometer, in: (1) facilitating personalized counselor-counselee communication; (2) increasing counselors' awareness of their counselees' psychosocial problems; and (3) facilitating the management of psychosocial problems during and after genetic counseling. This multicenter, randomized controlled trial will include 264 individuals undergoing cancer genetic counseling in two family cancer clinics in the Netherlands. Participants will be randomized to either: (1) an intervention group that completes the PAHC questionnaire, the results of which are made available to the genetic counselor prior to the counseling session; or (2) a control group that completes the PAHC questionnaire, but without feedback being given to the genetic counselor. The genetic counseling sessions will be audiotaped for content analysis. Additionally, study participants will be asked to complete questionnaires at baseline, three weeks after the initial counseling session, and four months after a telephone follow-up counseling session. The genetic counselors will be asked to complete questionnaires at the start of and at completion of the study, as well as a checklist directly after each counseling session. The questionnaires/checklists of the study include items on communication during genetic counseling, counselor awareness of their clients' psychosocial problems, the (perceived) need for professional psychosocial support, cancer worries, general distress, specific psychosocial problems, satisfaction with care received, and experience using the PAHC questionnaire. This study will provide empirical evidence regarding the efficacy of a relatively brief psychosocial screening questionnaire in terms of facilitating personalized communication, increasing counselors' awareness, and optimizing management of psychosocial problems in the cancer genetic counseling setting. This study is registered at the Netherlands Trial Register (NTR3205) and ClinicalTrials.gov (NCT01562431).

Speech Motor Control in Fluent and Dysfluent Speech Production of an Individual with Apraxia of Speech and Broca's Aphasia

ERIC Educational Resources Information Center

van Lieshout, Pascal H. H. M.; Bose, Arpita; Square, Paula A.; Steele, Catriona M.

2007-01-01

Apraxia of speech (AOS) is typically described as a motor-speech disorder with clinically well-defined symptoms, but without a clear understanding of the underlying problems in motor control. A number of studies have compared the speech of subjects with AOS to the fluent speech of controls, but only a few have included speech movement data and if…

An evolving problem: methamphetamine production and trafficking in the United States.

PubMed

Shukla, Rashi K; Crump, Jordan L; Chrisco, Emelia S

2012-11-01

Methamphetamine is a serious illicit drug problem in the United States and globally. For decades, methamphetamine has been supplied to the illicit market through local clandestine manufacturing and trafficking. In the early stages, illicit methamphetamine was produced and trafficked by motorcycle gangs and Mexican criminal groups. Over time, local clandestine manufacturing increasingly contributed to the illicit supply and broader methamphetamine problem. This review examines the evolution of the illicit methamphetamine supply in the U.S. A review of the literature on methamphetamine production and trafficking was conducted. Information was obtained from numerous sources including governmental reports, books and academic articles. Attempts to control the supply of methamphetamine have only led to short term disruptions in availability. Clandestine manufacturing and trafficking have undergone significant changes over the past several decades. Shifts in local production have regularly been counterbalanced by changes in production and trafficking from criminal organizations in Mexico. Transnational criminal organizations now control much of the methamphetamine supply in the U.S. and methamphetamine remains widely available. The supply of methamphetamine in the United States is dynamic. Producers and traffickers have adapted to control efforts and the problem continues. Control efforts focused on eliminating supply are limited at best. Copyright © 2012 Elsevier B.V. All rights reserved.

Feed Forward Neural Network and Optimal Control Problem with Control and State Constraints

NASA Astrophysics Data System (ADS)

Kmet', Tibor; Kmet'ová, Mária

2009-09-01

A feed forward neural network based optimal control synthesis is presented for solving optimal control problems with control and state constraints. The paper extends adaptive critic neural network architecture proposed by [5] to the optimal control problems with control and state constraints. The optimal control problem is transcribed into a nonlinear programming problem which is implemented with adaptive critic neural network. The proposed simulation method is illustrated by the optimal control problem of nitrogen transformation cycle model. Results show that adaptive critic based systematic approach holds promise for obtaining the optimal control with control and state constraints.

Sensory Motor and Functional Skills of Dizygotic Twins: One with Smith-Magenis Syndrome and a Twin Control

ERIC Educational Resources Information Center

Smith, Michaele R.; Hildenbrand, Hanna; Smith, Ann C. M.

2009-01-01

Smith-Magenis syndrome (SMS), the result of an interstitial deletion within chromosome 17p11.2, is a disorder that may include minor dysmorphic features, brachydactyly, short stature, hypotonia, speech delays, cognitive deficits, signs of peripheral neuropathy, scoliosis, and neurobehavioral problems including sleep disturbances and maladaptive…

Analysis and design of a capsule landing system and surface vehicle control system for Mars exporation

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

The problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars were investigated. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; navigation, terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks were studied: vehicle model design, mathematical modeling of dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement and transport parameter evaluation.

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

NASA Technical Reports Server (NTRS)

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

Investigation of problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks have been under study: vehicle model design, mathematical modeling of a dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer sybsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement.

Does the Incredible Years Teacher Classroom Management Training programme have positive effects for young children exhibiting severe externalizing problems in school?: a quasi-experimental pre-post study.

PubMed

Kirkhaug, Bente; Drugli, May Britt; Handegård, Bjørn Helge; Lydersen, Stian; Åsheim, Merethe; Fossum, Sturla

2016-10-26

Young children exhibiting severe externalizing problems in school are at risk of developing several poor outcomes. School-based intervention programs have been found to be effective for students with different problems, including those with behavioral problems, emotional distress, or social problems. The present study investigated whether the IY-TCM programme, as a universal stand-alone school intervention programme, reduced severe child externalizing problems as reported by the teacher, and evaluated if these children improved their social competence, internalizing problems, academic performances and student- teacher relationship as a result of the IY TCM training. A quasi-experimental pre-post study was conducted, including 21 intervention schools and 22 control schools. Children in 1 st - 3 rd grade (age 6-8 years) assessed by their teacher as having severe externalizing problems on the Sutter-Eyberg Student Behavior Inventory-Revised (SESBI-R) total Intensity score, were included in the study, N = 83 (65 boys and 18 girls). Treatment effects were evaluated using 3- level linear mixed models analysis. In our study we found no differences in change between the two conditions from baseline to follow-up in externalizing problems, social skills, internalizing problems and closeness with teacher. The intervention condition did however show advantageous development in terms of student-teacher conflicts and increased academic performances. The IY Teacher Classroom Management program is not sufficient being a stand-alone universal program in a Norwegian primary school setting, for students with severe externalizing problems. However; some important secondary findings were found. Still, young school children with severe externalizing problems are in need of more comprehensive and tailored interventions.

The BAPE 2 balloon-borne CO2

NASA Technical Reports Server (NTRS)

Degnan, J. J.; Walker, H. E.; Peruso, C. J.; Johnson, E. H.; Klein, B. J.; Mcelroy, J. H.

1972-01-01

The systems and techniques which were utilized in the experiment to establish an air-to-ground CO2 laser heterodyne link are described along with the successes and problems encountered when the heterodyne receiver and laser transmitter package were removed from the controlled environment of the laboratory. Major topics discussed include: existing systems and the underlying principles involved in their operation; experimental techniques and optical alignment methods which were found to be useful; theoretical calculations of signal strengths expected under a variety of test conditions and in actual flight; and the experimental results including problems encountered and their possible solutions.

Group Problem-Solving versus Lecture in College-Level Quantitative Analysis: The Good, the Bad, and the Ugly

NASA Astrophysics Data System (ADS)

Williamson, Vickie M.; Rowe, Marvin W.

2002-09-01

The purpose of this semester-long study was to investigate the effect of replacing traditional lecture with cooperative group problem-solving sessions in a junior-level quantitative analysis course. The control and treatment groups had the same instructor, met on the same day, had the same reading assignments, and had common exams. The instructor worked sample problems for the control group. In the treatment group, students were assigned to heterogeneous cooperative groups of 4. The groups solved problems presented on an overhead that were the same or equivalent in content and number to those used in the control group. Students were responsible for making sure that all members of the group could work each problem. The students' reasoning abilities were measured by the Test of Logical Thinking (TOLT). Groups were compared on quiz, exam, final, and course grades. Other data included attitudinal surveys, observations, field notes, interviews, and open-response evaluations. No significant differences were found in content measures. Differences were found in the number of students dropping the course and in the attitudes and perceptions of the two groups. Qualitative measures support a number of assertions concerning more positive attitudes and lower withdrawal rates in the treatment group, and a case for mixed delivery modes.

Quaternion regularization in celestial mechanics, astrodynamics, and trajectory motion control. III

NASA Astrophysics Data System (ADS)

Chelnokov, Yu. N.

2015-09-01

The present paper1 analyzes the basic problems arising in the solution of problems of the optimum control of spacecraft (SC) trajectory motion (including the Lyapunov instability of solutions of conjugate equations) using the principle of the maximum. The use of quaternion models of astrodynamics is shown to allow: (1) the elimination of singular points in the differential phase and conjugate equations and in their partial analytical solutions; (2) construction of the first integrals of the new quaternion; (3) a considerable decrease of the dimensions of systems of differential equations of boundary value optimization problems with their simultaneous simplification by using the new quaternion variables related with quaternion constants of motion by rotation transformations; (4) construction of general solutions of differential equations for phase and conjugate variables on the sections of SC passive motion in the simplest and most convenient form, which is important for the solution of optimum pulse SC transfers; (5) the extension of the possibilities of the analytical investigation of differential equations of boundary value problems with the purpose of identifying the basic laws of optimum control and motion of SC; (6) improvement of the computational stability of the solution of boundary value problems; (7) a decrease in the required volume of computation.

A Randomized Controlled Trial of Problem-Solving Therapy Compared to Cognitive Therapy for the Treatment of Insomnia in Adults

PubMed Central

Pech, Melissa; O'Kearney, Richard

2013-01-01

Study Objectives: To compare the efficacy of problem-solving therapy (PST) combined with behavioral sleep strategies to standard cognitive therapy (CT) combined with behavioral sleep strategies in the treatment of insomnia. Design: A six-week randomized controlled trial with one month follow-up. Setting: The Australian National University Psychology Clinic, Canberra, Australia. Participants: Forty-seven adults aged 18-60 years recruited from the community meeting the Research Diagnostic Criteria for insomnia. Interventions: Participants received 6 weeks of treatment including one group session (sleep education and hygiene, stimulus control instructions and progressive muscle relaxation) followed by 5 weeks of individual treatment of PST or CT. Measurements and Results: Primary outcomes included sleep efficiency (SE) from sleep diaries, the Insomnia Severity Index (ISI), and the Pittsburgh Sleep Quality Index (PSQI). Secondary measures assessed dysfunctional sleep beliefs, problem-solving skills and orientations, and worry. Both treatments produced significant post therapy improvements in sleep which were maintained at 1 month follow-up (on SE Cohen d = 1.42, 95% CI 1.02-1.87 for PST; d = 1.26, 95% CI 0.81-1.65 for CT; on ISI d = 1.46, 95% CI 1.03-1.88 for PST; d = 1.95, 95% CI 0.52-2.38 for CT; for PSQI d = 0.97, 95% CI 0.55-1.40 for PST and d = 1.34, 95% CI 0.90-1.79 for the CT). There were no differences in PST and CT in the size or rate of improvement in sleep although CT produced a significant faster rate of decline in negative beliefs about sleep than PST and there was a trend (P = 0.08) for PST to produce a faster rate of improvement in negative problem orientation than CT. Conclusions: The results provide preliminary support for problem solving treatment as an equally efficacious alternative component to cognitive therapy in psychological interventions for insomnia. Citation: Pech M; O'Kearney R. A randomized controlled trial of problem-solving therapy compared to cognitive therapy for the treatment of insomnia in adults. SLEEP 2013;36(5):739-749. PMID:23633757

Solid state electro-optic color filter and iris

NASA Technical Reports Server (NTRS)

1974-01-01

Test results obtained have confirmed the practicality of the solid state electro-optic filters as an optical control element in a television system. Neutral-density control range in excess of 1000:1 has been obtained on sample filters. Test results, measurements in a complete camera system, discussions of problem areas, analytical comparisons, and recommendations for future investigations are included.

A pilot effectiveness study of the Enhancing Parenting Skills (EPaS) 2014 programme for parents of children with behaviour problems: study protocol for a randomised controlled trial.

PubMed

Williams, Margiad Elen; Hutchings, Judy

2015-05-20

The Enhancing Parenting Skills (EPaS) 2014 programme is a home-based, health visitor-delivered parenting support programme for parents of children with identified behaviour problems. This trial aims to evaluate the effectiveness of the EPaS 2014 programme compared to a waiting-list treatment as usual control group. This is a pragmatic, multicentre randomised controlled trial. Sixty health visitors will each be asked to identify two families that have a child scoring above the clinical cut-off for behaviour problems using the Eyberg Child Behaviour Inventory (ECBI). Families recruited to the trial will be randomised in a 1:1 ratio into an intervention or waiting-list control group. Randomisation will occur within health visitor to ensure that each health visitor has one intervention family and one control family. The primary outcome is change in child behaviour problems as measured by the parent-reported ECBI. Secondary outcomes include other measures of child behaviour, parent behaviour, and parental depression as measured by parent-reports and an independent observation of parent and child behaviour. Follow-up measures will be collected 6-months after the collection of baseline measures. This is the first rigorous evaluation of the EPaS 2014 programme. The trial will provide important information on the effectiveness of a one-to-one home-based intervention, delivered by health visitors, for pre-school children with behaviour problems. It will also examine potential mediating (improved parent behaviour and/or improved parental depression) and moderating (single parent, teenage parent, poverty, low education level) factors. Current Controlled Trials ISRCTN06867279 (18 June 2014).

Preventing overuse shoulder injuries among throwing athletes: a cluster-randomised controlled trial in 660 elite handball players.

PubMed

Andersson, Stig Haugsboe; Bahr, Roald; Clarsen, Benjamin; Myklebust, Grethe

2017-07-01

Shoulder problems are highly prevalent among elite handball players. Reduced glenohumeral rotation, external rotation weakness and scapula dyskinesis have been identified as risk factors. Evaluate the effect of an exercise programme designed to reduce the prevalence of shoulder problems in elite handball. 45 elite handball teams (22 female teams, 23 male teams, 660 players) were cluster randomised (22 teams, 331 players in the intervention group, 23 teams, 329 players in the control group) and followed for 1 competitive season (7 months). The Oslo Sports Trauma Research Center (OSTRC) Shoulder Injury Prevention Programme, an exercise programme to increase glenohumeral internal rotation, external rotation strength and scapular muscle strength, as well as improve kinetic chain and thoracic mobility, was delivered by coaches and captains 3 times per week as a part of the handball warm-up. The main outcome measures, prevalence of shoulder problems and substantial shoulder problems, were measured monthly. The average prevalence of shoulder problems during the season was 17% (95% CI 16% to 19%) in the intervention group and 23% (95% CI 21% to 26%) in the control group (mean difference 6%). The average prevalence of substantial shoulder problems was 5% (95% CI 4% to 6%) in the intervention group and 8% (95% CI 7% to 9%) in the control group (mean difference 3%). Using generalised estimating equation models, a 28% lower risk of shoulder problems (OR 0.72, 95% CI 0.52 to 0.98, p=0.038) and 22% lower risk of substantial shoulder problems (OR 0.78, 95% CI 0.53 to 1.16, p=0.23) were observed in the intervention group compared with the control group. The OSTRC Shoulder Injury Prevention Programme reduced the prevalence of shoulder problems in elite handball and should be included as a part of the warm-up. ISRCTN96217107. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Classical Biological Control of Invasive Legacy Crop Pests: New Technologies Offer Opportunities to Revisit Old Pest Problems in Perennial Tree Crops

PubMed Central

Hoddle, Mark S.; Warner, Keith; Steggall, John; Jetter, Karen M.

2014-01-01

Advances in scientific disciplines that support classical biological control have provided “new tools” that could have important applications for biocontrol programs for some long-established invasive arthropod pests. We suggest that these previously unavailable tools should be used in biological control programs targeting “legacy pests”, even if they have been targets of previously unsuccessful biocontrol projects. Examples of “new tools” include molecular analyses to verify species identities and likely geographic area of origin, climate matching and ecological niche modeling, preservation of natural enemy genetic diversity in quarantine, the use of theory from invasion biology to maximize establishment likelihoods for natural enemies, and improved understanding of the interactions between natural enemy and target pest microbiomes. This review suggests that opportunities exist for revisiting old pest problems and funding research programs using “new tools” for developing biological control programs for “legacy pests” could provide permanent suppression of some seemingly intractable pest problems. As a case study, we use citricola scale, Coccus pseudomagnoliarum, an invasive legacy pest of California citrus, to demonstrate the potential of new tools to support a new classical biological control program targeting this insect. PMID:26463063

Predicting Condom Use Attitudes, Norms, and Control Beliefs in Hispanic Problem Behavior Youth: The Effects of Family Functioning and Parent-Adolescent Communication about Sex on Condom Use

ERIC Educational Resources Information Center

Malcolm, Shandey; Huang, Shi; Cordova, David; Freitas, Derek; Arzon, Margaret; Jimenez, Giselle Leon; Pantin, Hilda; Prado, Guillermo

2013-01-01

Hispanic problem behavior youth are at an increased risk of engaging in HIV risk behaviors, including low condom use. However, relatively little research has examined factors that affect condom use in this population. Although research indicates that family processes, such as higher levels of family functioning and open parent-adolescent…

Psychological treatments in intellectual disability: the challenges of building a good evidence base.

PubMed

Bhaumik, Sabyasachi; Gangadharan, Satheesh; Hiremath, Avinash; Russell, Paul Swamidhas Sudhakar

2011-06-01

Psychological treatments are widely used for the management of mental health and behavioural problems in people with intellectual disabilities. The evidence base, including the cost-effectiveness of such interventions, is limited. This editorial explores the current evidence base and analyses its strengths and limitations. The editorial also highlights current problems in conducting randomised controlled trials in this area and suggests a way forward.

Effect of correlations on controllability transition in network control

PubMed Central

Nie, Sen; Wang, Xu-Wen; Wang, Bing-Hong; Jiang, Luo-Luo

2016-01-01

The network control problem has recently attracted an increasing amount of attention, owing to concerns including the avoidance of cascading failures of power-grids and the management of ecological networks. It has been proven that numerical control can be achieved if the number of control inputs exceeds a certain transition point. In the present study, we investigate the effect of degree correlation on the numerical controllability in networks whose topological structures are reconstructed from both real and modeling systems, and we find that the transition point of the number of control inputs depends strongly on the degree correlation in both undirected and directed networks with moderately sparse links. More interestingly, the effect of the degree correlation on the transition point cannot be observed in dense networks for numerical controllability, which contrasts with the corresponding result for structural controllability. In particular, for directed random networks and scale-free networks, the influence of the degree correlation is determined by the types of correlations. Our approach provides an understanding of control problems in complex sparse networks. PMID:27063294

A combined stochastic feedforward and feedback control design methodology with application to autoland design

NASA Technical Reports Server (NTRS)

Halyo, Nesim

1987-01-01

A combined stochastic feedforward and feedback control design methodology was developed. The objective of the feedforward control law is to track the commanded trajectory, whereas the feedback control law tries to maintain the plant state near the desired trajectory in the presence of disturbances and uncertainties about the plant. The feedforward control law design is formulated as a stochastic optimization problem and is embedded into the stochastic output feedback problem where the plant contains unstable and uncontrollable modes. An algorithm to compute the optimal feedforward is developed. In this approach, the use of error integral feedback, dynamic compensation, control rate command structures are an integral part of the methodology. An incremental implementation is recommended. Results on the eigenvalues of the implemented versus designed control laws are presented. The stochastic feedforward/feedback control methodology is used to design a digital automatic landing system for the ATOPS Research Vehicle, a Boeing 737-100 aircraft. The system control modes include localizer and glideslope capture and track, and flare to touchdown. Results of a detailed nonlinear simulation of the digital control laws, actuator systems, and aircraft aerodynamics are presented.

Kernel-based least squares policy iteration for reinforcement learning.

PubMed

Xu, Xin; Hu, Dewen; Lu, Xicheng

2007-07-01

In this paper, we present a kernel-based least squares policy iteration (KLSPI) algorithm for reinforcement learning (RL) in large or continuous state spaces, which can be used to realize adaptive feedback control of uncertain dynamic systems. By using KLSPI, near-optimal control policies can be obtained without much a priori knowledge on dynamic models of control plants. In KLSPI, Mercer kernels are used in the policy evaluation of a policy iteration process, where a new kernel-based least squares temporal-difference algorithm called KLSTD-Q is proposed for efficient policy evaluation. To keep the sparsity and improve the generalization ability of KLSTD-Q solutions, a kernel sparsification procedure based on approximate linear dependency (ALD) is performed. Compared to the previous works on approximate RL methods, KLSPI makes two progresses to eliminate the main difficulties of existing results. One is the better convergence and (near) optimality guarantee by using the KLSTD-Q algorithm for policy evaluation with high precision. The other is the automatic feature selection using the ALD-based kernel sparsification. Therefore, the KLSPI algorithm provides a general RL method with generalization performance and convergence guarantee for large-scale Markov decision problems (MDPs). Experimental results on a typical RL task for a stochastic chain problem demonstrate that KLSPI can consistently achieve better learning efficiency and policy quality than the previous least squares policy iteration (LSPI) algorithm. Furthermore, the KLSPI method was also evaluated on two nonlinear feedback control problems, including a ship heading control problem and the swing up control of a double-link underactuated pendulum called acrobot. Simulation results illustrate that the proposed method can optimize controller performance using little a priori information of uncertain dynamic systems. It is also demonstrated that KLSPI can be applied to online learning control by incorporating an initial controller to ensure online performance.

Simulation of a class of hazardous situations in the ICS «INM RAS - Baltic Sea»

NASA Astrophysics Data System (ADS)

Zakharova, Natalia; Agoshkov, Valery; Aseev, Nikita; Parmuzin, Eugene; Sheloput, Tateana; Shutyaev, Victor

2017-04-01

Development of Informational Computational Systems (ICS) for data assimilation procedures is one of multidisciplinary problems. To study and solve these problems one needs to apply modern results from different disciplines and recent developments in mathematical modeling, theory of adjoint equations and optimal control, inverse problems, numerical methods theory, numerical algebra, scientific computing and processing of satellite data. In this work the results on the ICS development for PC-ICS "INM RAS - Baltic Sea" are presented. We discuss practical problems studied by ICS. The System includes numerical model of the Baltic Sea thermodynamics, the new oil spill model describing the propagation of a slick at the Sea surface (Agoshkov, Aseev et al., 2014) and the optimal ship route calculating block (Agoshkov, Zayachkovsky et al., 2014). The ICS is based on the INMOM numerical model of the Baltic Sea thermodynamics (Zalesny et al., 2013). It is possible to calculate main hydrodynamic parameters (temperature, salinity, velocities, sea level) using user-friendly interface of the ICS. The System includes data assimilation procedures (Agoshkov, 2003, Parmuzin, Agoshkov, 2012) and one can use the block of variational assimilation of the sea surface temperature in order to obtain main hydrodynamic parameters. Main possibilities of the ICS and several numerical experiments are presented in the work. By the problem of risk control is meant a problem of determination of optimal resources quantity which are necessary for decreasing the risk to some acceptable value. Mass of oil slick is chosen as a function of control. For the realization of the random variable the quadratic "functional of cost" is introduced. It comprises cleaning costs and deviation of damage of oil pollution from its acceptable value. The problem of minimization of this functional is solved based on the methods of optimal control and the theory of adjoint equations. The solution of this problem is explicitly found. The study was supported by the Russian Foundation for Basic Research (project 16-31-00510) and by the Russian Science Foundation (project №14-11-00609). V. I. Agoshkov, Methods of Optimal Control and Adjoint Equations in Problems of Mathematical Physics. INM RAS, Moscow, 2003 (in Russian). V. B. Zalesny, A. V. Gusev, V. O. Ivchenko, R. Tamsalu, and R. Aps, Numerical model of the Baltic Sea circulation. Russ. J. Numer. Anal. Math. Modelling 28 (2013), No. 1, 85-100. V.I. Agoshkov, A.O. Zayachkovskiy, R. Aps, P. Kujala, and J. Rytkönen. Risk theory based solution to the problem of optimal vessel route // Russian Journal of Numerical Analysis and Mathematical Modelling. 2014. Volume 29, Issue 2, Pages 69-78. Agoshkov, V., Aseev, N., Aps, R., Kujala, P., Rytkönen, J., Zalesny, V. The problem of control of oil pollution risk in the Baltic Sea // Russian Journal of Numerical Analysis and Mathematical Modelling. 2014. Volume 29, Issue 2, Pages 93-105. E. I. Parmuzin and V. I. Agoshkov, Numerical solution of the variational assimilation problem for sea surface temperature in the model of the Black Sea dynamics. Russ. J. Numer. Anal. Math. Modelling 27 (2012), No. 1, 69-94. Olof Liungman and Johan Mattsson. Scientic Documentation of Seatrack Web; physical processes, algorithms and references, 2011.

Reflective cracking control : interim report - fourth year.

DOT National Transportation Integrated Search

1999-07-01

Reflective cracking has long been considered a major problem associated with asphalt : pavements. Several methods including milling, crack sealing and fabric membranes have : been used in an attempt to eliminate or delay the reflective cracking proce...

What Health Problems Can Develop during Pregnancy?

MedlinePlus

... glucose challenge screening test around 24 to 28 weeks of pregnancy, followed by a diagnostic test called ... of protein in the urine after the 20th week of pregnancy), and cesarean birth . Treatment includes controlling ...

Accidental Bowel Leakage

MedlinePlus

... Women with a bowel control problem may leak gas or liquid or solid stool. Other symptoms may include the ... which can lead to leakage of solid or liquid stool (feces) or gas. Anoscopy: An exam of the anus using an ...

Guidelines for software inspections

NASA Technical Reports Server (NTRS)

1983-01-01

Quality control inspections are software problem finding procedures which provide defect removal as well as improvements in software functionality, maintenance, quality, and development and testing methodology is discussed. The many side benefits include education, documentation, training, and scheduling.

Problems of increased transport load as a result of implementation of projects of high-rise constructions

NASA Astrophysics Data System (ADS)

Provotorov, Ivan; Gasilov, Valentin; Anisimova, Nadezhda

2018-03-01

The structure of problems of high-rise construction us suggested, which includes the impact on environment, design solutions, transportation problems, financial costs for construction and operation, and others. Positive and negative aspects of high-rise construction are considered. One of the basic problems of high-rise construction is the problem of increased transport load. Construction of the subway on the basis of the concession mechanism, with the use of unmanned control of rolling stock is proposed as the most expedient solution. An evaluation of the effectiveness of this project is presented, it shows quite high performance indicators for a private investor. Main problems that the project implementation may face in conditions of lack of scientific and methodological support are outlined.

Internet-Based Acceptance and Commitment Therapy for Psychological Distress Experienced by People With Hearing Problems: Study Protocol for a Randomized Controlled Trial.

PubMed

Molander, Peter; Hesser, Hugo; Weineland, Sandra; Bergwall, Kajsa; Buck, Sonia; Hansson-Malmlöf, Johan; Lantz, Henning; Lunner, Thomas; Andersson, Gerhard

2015-09-01

Psychological distress and psychiatric symptoms are prevalent among people with hearing loss or other audiological conditions, but psychological interventions for these groups are rare. This article describes the study protocol for a randomized controlled trial for evaluating the effect of a psychological treatment delivered over the Internet for individuals with hearing problems and concurrent psychological distress. Participants who are significantly distressed will be randomized to either an 8-week Internet-delivered acceptance-based cognitive behavioral therapy (i.e., acceptance and commitment therapy [ACT]), or wa it-list control. We aim to include measures of distress associated with hearing difficulties, anxiety, and depression. In addition, we aim to measure acceptance associated with hearing difficulties as well as quality of life. The results of the trial may further our understanding of how to best treat people who present problems with both psychological distress and hearing in using the Internet.

Robust preview control for a class of uncertain discrete-time systems with time-varying delay.

PubMed

Li, Li; Liao, Fucheng

2018-02-01

This paper proposes a concept of robust preview tracking control for uncertain discrete-time systems with time-varying delay. Firstly, a model transformation is employed for an uncertain discrete system with time-varying delay. Then, the auxiliary variables related to the system state and input are introduced to derive an augmented error system that includes future information on the reference signal. This leads to the tracking problem being transformed into a regulator problem. Finally, for the augmented error system, a sufficient condition of asymptotic stability is derived and the preview controller design method is proposed based on the scaled small gain theorem and linear matrix inequality (LMI) technique. The method proposed in this paper not only solves the difficulty problem of applying the difference operator to the time-varying matrices but also simplifies the structure of the augmented error system. The numerical simulation example also illustrates the effectiveness of the results presented in the paper. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

An alcohol training program improves Chinese nurses' knowledge, self-efficacy, and practice: a randomized controlled trial.

PubMed

Tsai, Yun-Fang; Tsai, Mei-Chu; Lin, Yea-Pyng; Weng, Chih-Erh; Chou, Yu-Ling; Chen, Ching-Yen

2011-05-01

Excessive alcohol use has been associated with health, social and legal problems. Helping health care providers to manage hazardous or harmful drinkers is an important worldwide issue. Alcohol is a legal and accessible substance in Taiwan and is viewed as an acceptable drink for relieving stress and enhancing socialization in Chinese culture. These cultural factors may contribute to drinking problems being easily ignored and to lack of alcohol training programs for health care providers. For this randomized controlled clinical trial with 1- and 3-month posttests, six hospitals were randomly selected throughout Taiwan and were randomly assigned to an experimental or control group. In these hospitals, nurses were selected from the Emergency Department, psychiatric, and gastrointestinal medical-surgical units where most patients with alcohol problems are seen. For the experimental group, nurses received a 1.5-hour alcohol training program consisting of an introduction to alcohol, factors influencing alcohol drinking, impacts of high-risk drinking on a person, as well as introduction to and practice of the Alcohol Use Disorders Identification Test and brief alcohol intervention. The program also discussed Taiwanese nurses' perceived barriers and facilitators to intervening for problem alcohol use. Teaching strategies included lecture, discussion, demonstration, practice, role-playing, and sharing experiences. The control group did not receive any training. Data were collected at pretest, 1-month, and 3-month posttests using a self-report questionnaire on knowledge, self-efficacy, clinical practice scales, and a demographic form. The study was completed by 395 nurses, including 191 nurses in the experimental group and 204 nurses in the control group. Knowledge scores significantly improved in the experimental group at the 1- and 3-month posttests but not for the control group. Similarly, nurses' self-efficacy and clinical practice scores significantly improved in the experimental group at the 3-month posttest but not for the control group. Our results suggest that the alcohol training program could be used to enhance nurses' alcohol knowledge, self-efficacy, and clinical practice not only in Taiwan but also other countries. Copyright © 2011 by the Research Society on Alcoholism.

Control Technologies for Room Air-conditioner and Packaged Air-conditioner

NASA Astrophysics Data System (ADS)

Ito, Nobuhisa

Trends of control technologies about air-conditioning machineries, especially room or packaged air conditioners, are presented in this paper. Multiple air conditioning systems for office buildings are mainly described as one application of the refrigeration cycle control technologies including sensors for thermal comfort and heating/ cooling loads are also described as one of the system control technologies. Inverter systems and related technologies for driving variable speed compressors are described in both case of including induction motors and brushless DC motors. Technologies for more accurate control to meet various kind of regulations such as ozone layer destruction, energy saving and global warming, and for eliminating harmonic distortion of power source current, as a typical EMC problem, will be urgently desired.

Development and validation of the hypoglycaemia problem-solving scale for people with diabetes mellitus

PubMed Central

Juang, Jyuhn-Huarng; Lin, Chia-Hung

2016-01-01

Objective To develop and psychometrically test a new instrument, the hypoglycaemia problem-solving scale (HPSS), which was designed to measure how well people with diabetes mellitus manage their hypoglycaemia-related problems. Methods A cross-sectional survey design approach was used to validate the performance assessment instrument. Patients who had a diagnosis of type 1 or type 2 diabetes mellitus for at least 1 year, who were being treated with insulin and who had experienced at least one hypoglycaemic episode within the previous 6 months were eligible for inclusion in the study. Results A total of 313 patients were included in the study. The initial draft of the HPSS included 28 items. After exploratory factor analysis, the 24-item HPSS consisted of seven factors: problem-solving perception, detection control, identifying problem attributes, setting problem-solving goals, seeking preventive strategies, evaluating strategies, and immediate management. The Cronbach’s α for the total HPSS was 0.83. Conclusions The HPSS was verified as being valid and reliable. Future studies should further test and improve the instrument to increase its effectiveness in helping people with diabetes manage their hypoglycaemia-related problems. PMID:27059292

Development and validation of the hypoglycaemia problem-solving scale for people with diabetes mellitus.

PubMed

Wu, Fei-Ling; Juang, Jyuhn-Huarng; Lin, Chia-Hung

2016-06-01

To develop and psychometrically test a new instrument, the hypoglycaemia problem-solving scale (HPSS), which was designed to measure how well people with diabetes mellitus manage their hypoglycaemia-related problems. A cross-sectional survey design approach was used to validate the performance assessment instrument. Patients who had a diagnosis of type 1 or type 2 diabetes mellitus for at least 1 year, who were being treated with insulin and who had experienced at least one hypoglycaemic episode within the previous 6 months were eligible for inclusion in the study. A total of 313 patients were included in the study. The initial draft of the HPSS included 28 items. After exploratory factor analysis, the 24-item HPSS consisted of seven factors: problem-solving perception, detection control, identifying problem attributes, setting problem-solving goals, seeking preventive strategies, evaluating strategies, and immediate management. The Cronbach's α for the total HPSS was 0.83. The HPSS was verified as being valid and reliable. Future studies should further test and improve the instrument to increase its effectiveness in helping people with diabetes manage their hypoglycaemia-related problems. © The Author(s) 2016.

Sensitivity analysis of discrete structural systems: A survey

NASA Technical Reports Server (NTRS)

Adelman, H. M.; Haftka, R. T.

1984-01-01

Methods for calculating sensitivity derivatives for discrete structural systems are surveyed, primarily covering literature published during the past two decades. Methods are described for calculating derivatives of static displacements and stresses, eigenvalues and eigenvectors, transient structural response, and derivatives of optimum structural designs with respect to problem parameters. The survey is focused on publications addressed to structural analysis, but also includes a number of methods developed in nonstructural fields such as electronics, controls, and physical chemistry which are directly applicable to structural problems. Most notable among the nonstructural-based methods are the adjoint variable technique from control theory, and the Green's function and FAST methods from physical chemistry.

Availability of feature-oriented scanning probe microscopy for remote-controlled measurements on board a space laboratory or planet exploration Rover.

PubMed

Lapshin, Rostislav V

2009-06-01

Prospects for a feature-oriented scanning (FOS) approach to investigations of sample surfaces, at the micrometer and nanometer scales, with the use of scanning probe microscopy under space laboratory or planet exploration rover conditions, are examined. The problems discussed include decreasing sensitivity of the onboard scanning probe microscope (SPM) to temperature variations, providing autonomous operation, implementing the capabilities for remote control, self-checking, self-adjustment, and self-calibration. A number of topical problems of SPM measurements in outer space or on board a planet exploration rover may be solved via the application of recently proposed FOS methods.

[Commentary on "group and organization: a dimension of collaboration of anthropology and epidemiology" by Song LM and Wang N].

PubMed

Liao, Su-Su; Zhang, Qing-Ning; Hou, Lei

2012-10-01

Epidemiology, as the study of occurrence and distribution of diseases or health events in specified populations and the application of the study to control health problems, is not just a method to study determinants of diseases at individual level through analysis of mass data based on individuals. To achieve the aims on the control of health problems in specified populations, Epidemiology should be public health-oriented to reduce incidence, prevalence and mortality, and should include study on determinants at the population level. Interdisplinarity and systems science will facilitate the breakthrough in improving health of the populations.

Reintegration after bone marrow transplantation.

PubMed

Baker, F; Zabora, J; Polland, A; Wingard, J

1999-01-01

This study examines the problems of bone marrow transplantation (BMT) survivors in returning to "normal" life in the community after BMT. Before being released from The Johns Hopkins Oncology Center, 84 recipients of BMT were interviewed regarding their quality of life and psychosocial adaptation. Survivors were reinterviewed at 6 months, and at 1 year post-BMT, producing considerable qualitative data regarding their problems in living. Eighty-four patients who had received BMT completed qualitative interviews and standardized measures before treatment, before the return home, and at 6 and 12 months post-BMT. The interviews were subjected to a content analysis methodology to establish units and categories to examine the body of material. Content analysis of these interviews from the first year after BMT identified three areas of psychosocial morbidity; 1) physical problems, which included fatigue, appearance, troubles in eating, and physical restrictions; 2) psychological problems, which included fears about the future, sense of loss of control, anxiety, and depression; and 3) community reintegration problems, which included difficulty in returning to former social roles, separation from home, family, and friends, difficulty in resuming social relations, dealing with stigmatization, problems with family and children, and financial and employment difficulties. Identification of these problems for BMT survivors can be used to guide the development of specific materials and services to prepare recipients of BMTs and their families for life after the transplant. These qualitative results can also be used to direct the development of assessment tools to identify potential patient and family problems.

Advanced theoretical and experimental studies in automatic control and information systems. [including mathematical programming and game theory

NASA Technical Reports Server (NTRS)

Desoer, C. A.; Polak, E.; Zadeh, L. A.

1974-01-01

A series of research projects is briefly summarized which includes investigations in the following areas: (1) mathematical programming problems for large system and infinite-dimensional spaces, (2) bounded-input bounded-output stability, (3) non-parametric approximations, and (4) differential games. A list of reports and papers which were published over the ten year period of research is included.

An interactive approach based on a discrete differential evolution algorithm for a class of integer bilevel programming problems

NASA Astrophysics Data System (ADS)

Li, Hong; Zhang, Li; Jiao, Yong-Chang

2016-07-01

This paper presents an interactive approach based on a discrete differential evolution algorithm to solve a class of integer bilevel programming problems, in which integer decision variables are controlled by an upper-level decision maker and real-value or continuous decision variables are controlled by a lower-level decision maker. Using the Karush--Kuhn-Tucker optimality conditions in the lower-level programming, the original discrete bilevel formulation can be converted into a discrete single-level nonlinear programming problem with the complementarity constraints, and then the smoothing technique is applied to deal with the complementarity constraints. Finally, a discrete single-level nonlinear programming problem is obtained, and solved by an interactive approach. In each iteration, for each given upper-level discrete variable, a system of nonlinear equations including the lower-level variables and Lagrange multipliers is solved first, and then a discrete nonlinear programming problem only with inequality constraints is handled by using a discrete differential evolution algorithm. Simulation results show the effectiveness of the proposed approach.

Modeling and analysis of pinhole occulter experiment: Initial study phase

NASA Technical Reports Server (NTRS)

Vandervoort, R. J.

1985-01-01

The feasibility of using a generic simulation, TREETOPS, to simulate the Pinhole/Occulter Facility (P/OF) to be tested on the space shuttle was demonstrated. The baseline control system was used to determine the pointing performance of the P/OF. The task included modeling the structure as a three body problem (shuttle-instrument pointing system- P/OP) including the flexibility of the 32 meter P/OF boom. Modeling of sensors, actuators, and control algorithms was also required. Detailed mathematical models for the structure, sensors, and actuators are presented, as well as the control algorithm and corresponding design procedure. Closed loop performance using this controller and computer listings for the simulator are also given.

Computer program for prediction of fuel consumption statistical data for an upper stage three-axes stabilized on-off control system

NASA Technical Reports Server (NTRS)

1982-01-01

A FORTRAN coded computer program and method to predict the reaction control fuel consumption statistics for a three axis stabilized rocket vehicle upper stage is described. A Monte Carlo approach is used which is more efficient by using closed form estimates of impulses. The effects of rocket motor thrust misalignment, static unbalance, aerodynamic disturbances, and deviations in trajectory, mass properties and control system characteristics are included. This routine can be applied to many types of on-off reaction controlled vehicles. The pseudorandom number generation and statistical analyses subroutines including the output histograms can be used for other Monte Carlo analyses problems.

It's all about gains: Risk preferences in problem gambling.

PubMed

Ring, Patrick; Probst, Catharina C; Neyse, Levent; Wolff, Stephan; Kaernbach, Christian; van Eimeren, Thilo; Camerer, Colin F; Schmidt, Ulrich

2018-06-07

Problem gambling is a serious socioeconomic problem involving high individual and social costs. In this article, we study risk preferences of problem gamblers including their risk attitudes in the gain and loss domains, their weighting of probabilities, and their degree of loss aversion. Our findings indicate that problem gamblers are systematically more risk taking and less sensitive toward changes in probabilities in the gain domain only. Neither their risk attitudes in the loss domain nor their degree of loss aversion are significantly different from the controls. Additional evidence for a similar degree of sensitivity toward negative outcomes is gained from skin conductance data-a psychophysiological marker for emotional arousal-in a threat-of-shock task. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Associations between cognition and internalizing problems in young adults with early-onset schizophrenia: A 13-year follow-up study.

PubMed

Strugstad, Benedicte; Lau, Bjørn; Glenne Øie, Merete

2018-04-12

The present follow-up study examines the associations between cognition and parent-rated internalizing problems among adolescents with early-onset schizophrenia (EOS) at baseline (T1) and self-rated internalizing problems 13 years later (T2). Twelve individuals (8 male/4 female) with EOS and 30 healthy controls (16 male/14 female) were included in the study. All were between 12 and 18 years of age at T1. Internalizing problems were measured with the Achenbach System of Empirically Based Assessment Internalizing Scale. Cognition was examined with a neuropsychological test battery measuring auditory attention/working memory, visuomotor processing, cognitive flexibility and verbal memory. Compared to healthy controls, the EOS group had significant cognitive deficits and more internalizing problems both at T1 and T2. There was no correlation between parent-rated internalizing problems at T1 and self-rated internalizing problems at T2 in the EOS group. However, deficits in auditory attention/working memory at T1 were significantly associated with internalizing problems at T2. A focus on improving the treatment of cognitive impairments may be important in preventing the development of internalizing problems in young patients with schizophrenia. The small sample size of the study is a limitation and further research is recommended. Copyright © 2018 Elsevier B.V. All rights reserved.

Problems related to the integration of fault tolerant aircraft electronic systems

NASA Technical Reports Server (NTRS)

Bannister, J. A.; Adlakha, V.; Triyedi, K.; Alspaugh, T. A., Jr.

1982-01-01

Problems related to the design of the hardware for an integrated aircraft electronic system are considered. Taxonomies of concurrent systems are reviewed and a new taxonomy is proposed. An informal methodology intended to identify feasible regions of the taxonomic design space is described. Specific tools are recommended for use in the methodology. Based on the methodology, a preliminary strawman integrated fault tolerant aircraft electronic system is proposed. Next, problems related to the programming and control of inegrated aircraft electronic systems are discussed. Issues of system resource management, including the scheduling and allocation of real time periodic tasks in a multiprocessor environment, are treated in detail. The role of software design in integrated fault tolerant aircraft electronic systems is discussed. Conclusions and recommendations for further work are included.

[Oral motor dysfunction, feeding problems and nutritional status in children with cerebral palsy].

PubMed

Hou, Mei; Fu, Ping; Zhao, Jian-hui; Lan, Kun; Zhang, Hong

2004-10-01

This study was undertaken to investigate the clinical features of oral motor dysfunction and feeding problems as well as the nutritional status of children with cerebral palsy (CP). Fifty-nine CP children, 39 boys and 20 girls, mean age 31 months (20 to 72 months), were recruited. Their parents were interviewed for high risk factors and feeding history. Each case was assessed for oral motor and feeding problems based on oral motor and feeding skill score; for nutritional status by measurement of weight, height; neurologically for type of cerebral palsy and for developmental age by Gesell's developmental scale. Equal number of age and sex matched controls were included for comparison of nutritional status, oral motor and feeding skill score. Among 59 patients, 51 cases had oral motor dysfunction and 55 cases had feeding problems including all athtosis, spastic tetraplegia, and 16 had spastic diplegia. The scores of both the mean oral motor function and feeding skill of CP children were significantly lower than those of the controls (P < 0.001). Main food of children with cerebral palsy consisted of liquid and semisolid diet. Body weight and height below the 25th percentile were found in 13 cases and 19 cases, respectively. The majority of the children with cerebral palsy had oral motor dysfunction and feeding problems which appeared in early age and disturbed the growth and nutritional status. Thorough assessment for oral motor function, feeding problems and nutritional status of CP children is indicated in order to start timely rehabilitation and nutritional interventions which can significantly improve their nutritional status and quality of life.

Digital control of magnetic bearings in a cryogenic cooler

NASA Technical Reports Server (NTRS)

Feeley, J.; Law, A.; Lind, F.

1990-01-01

This paper describes the design of a digital control system for control of magnetic bearings used in a spaceborne cryogenic cooler. The cooler was developed by Philips Laboratories for the NASA Goddard Space Flight Center. Six magnetic bearing assemblies are used to levitate the piston, displacer, and counter-balance of the cooler. The piston and displacer are driven by linear motors in accordance with Stirling cycle thermodynamic principles to produce the desired cooling effect. The counter-balance is driven by a third linear motor to cancel motion induced forces that would otherwise be transmitted to the spacecraft. An analog control system is currently used for bearing control. The purpose of this project is to investigate the possibilities for improved performance using digital control. Areas for potential improvement include transient and steady state control characteristics, robustness, reliability, adaptability, alternate control modes, size, weight, and cost. The present control system is targeted for the Intel 80196 microcontroller family. The eventual introduction of application specific integrated circuit (ASIC) technology to this problem may produce a unique and elegant solution both here and in related industrial problems.

Volterra-series-based nonlinear system modeling and its engineering applications: A state-of-the-art review

NASA Astrophysics Data System (ADS)

Cheng, C. M.; Peng, Z. K.; Zhang, W. M.; Meng, G.

2017-03-01

Nonlinear problems have drawn great interest and extensive attention from engineers, physicists and mathematicians and many other scientists because most real systems are inherently nonlinear in nature. To model and analyze nonlinear systems, many mathematical theories and methods have been developed, including Volterra series. In this paper, the basic definition of the Volterra series is recapitulated, together with some frequency domain concepts which are derived from the Volterra series, including the general frequency response function (GFRF), the nonlinear output frequency response function (NOFRF), output frequency response function (OFRF) and associated frequency response function (AFRF). The relationship between the Volterra series and other nonlinear system models and nonlinear problem solving methods are discussed, including the Taylor series, Wiener series, NARMAX model, Hammerstein model, Wiener model, Wiener-Hammerstein model, harmonic balance method, perturbation method and Adomian decomposition. The challenging problems and their state of arts in the series convergence study and the kernel identification study are comprehensively introduced. In addition, a detailed review is then given on the applications of Volterra series in mechanical engineering, aeroelasticity problem, control engineering, electronic and electrical engineering.

Organisational innovation and control practices: the case of public-private mix in tuberculosis control in India.

PubMed

Engel, Nora; van Lente, Harro

2014-07-01

Partnerships between public and private healthcare providers are often seen as an important way to improve health care in resource-constrained settings. Despite the reconfirmed policy support for including private providers into public tuberculosis control in India, the public-private mix (PPM) activities continue to face apprehension at local implementation sites. This article investigates the causes for those difficulties by examining PPM initiatives as cases of organisational innovation. It examines findings from semi-structured interviews, observations and document analyses in India around three different PPM models and the attempts of innovating and scaling up. The results reveal that in PPM initiatives underlying problem definitions and different control practices, including supervision, standardisation and culture, continue to clash and ultimately hinder the scaling up of PPM. Successful PPM initiatives require organisational control practices which are rooted in different professions to be bridged. This entails difficult balancing acts between innovation and control. The innovators handle those differently, based on their own ideas of the problem that PPM should address and their own control practices. We offer new perspectives on why collaboration is so difficult and show a possible way to mitigate the established apprehensions between professions in order to make organisational innovations, such as PPM, sustainable and scalable. © 2013 The Authors Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Systematic Review of Universal Resilience-Focused Interventions Targeting Child and Adolescent Mental Health in the School Setting.

PubMed

Dray, Julia; Bowman, Jenny; Campbell, Elizabeth; Freund, Megan; Wolfenden, Luke; Hodder, Rebecca K; McElwaine, Kathleen; Tremain, Danika; Bartlem, Kate; Bailey, Jacqueline; Small, Tameka; Palazzi, Kerrin; Oldmeadow, Christopher; Wiggers, John

2017-10-01

To examine the effect of universal, school-based, resilience-focused interventions on mental health problems in children and adolescents. Eligible studies were randomized controlled trials (RCTs) of universal, school-based interventions that included strategies to strengthen a minimum of 3 internal resilience protective factors, and included an outcome measure of mental health problems in children and adolescents aged 5 to 18 years. Six databases were searched from 1995 to 2015. Results were pooled in meta-analyses by mental health outcome (anxiety symptoms, depressive symptoms, hyperactivity, conduct problems, internalizing problems, externalizing problems, and general psychological distress), for all trials (5-18 years). Subgroup analyses were conducted by age (child: 5-10 years; adolescent: 11-18 years), length of follow-up (short: post-≤12 months; long: >12 months), and gender (narrative). A total of 57 included trials were identified from 5,984 records, with 49 contributing to meta-analyses. For all trials, resilience-focused interventions were effective relative to a control in reducing 4 of 7 outcomes: depressive symptoms, internalizing problems, externalizing problems, and general psychological distress. For child trials (meta-analyses for 6 outcomes), interventions were effective for anxiety symptoms and general psychological distress. For adolescent trials (meta-analyses for 5 outcomes), interventions were effective for internalizing problems. For short-term follow-up, interventions were effective for 2 of 7 outcomes: depressive symptoms and anxiety symptoms. For long-term follow-up (meta-analyses for 5 outcomes), interventions were effective for internalizing problems. The findings may suggest most promise for using universal resilience-focused interventions at least for short-term reductions in depressive and anxiety symptoms for children and adolescents, particularly if a cognitive-behavioral therapy-based approach is used. The limited number of trials providing data amenable for meta-analysis for some outcomes and subgroups, the variability of interventions, study quality, and bias mean that it is not possible to draw more specific conclusions. Identifying what intervention qualities (such as number and type of protective factor) achieve the greatest positive effect per mental health problem outcome remains an important area for future research. Systematic Review of Universal Resilience Interventions Targeting Child and Adolescent Mental Health in the School Setting; http://dx.doi.org/10.1186/s13643-015-0172-6; PROSPERO CRD42015025908. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

The Development of the CONDUIT Advanced Control System Design and Evaluation Interface with a Case Study Application to an Advanced Fly by Wire Helicopter Design

NASA Technical Reports Server (NTRS)

Colbourne, Jason

1999-01-01

This report details the development and use of CONDUIT (Control Designer's Unified Interface). CONDUIT is a design tool created at Ames Research Center for the purpose of evaluating and optimizing aircraft control systems against handling qualities. Three detailed design problems addressing the RASCAL UH-60A Black Hawk are included in this report to show the application of CONDUIT to helicopter control system design.

Control Scheme of River-lake System from the View of Ecological Sponge Basin aiming at Sponge City Construction

NASA Astrophysics Data System (ADS)

Ding, X.; Liu, J.; Yang, Z.

2017-12-01

China is in the rapid advance of urbanization, and is promoting the Sponge City Construction (SCC) with the characteristics of natural accumulation, natural infiltration and natural purification. The Chinese government selected 16 and 14 cities as pilot cities in 2015 and 2016 respectively to carry out SCC taking Low Impact Development (LID) as the concept. However, in 2015 and 2016, water-logging occurred in 10 cities and 9 cities respectively during the pilot cities. Therefore, relying solely on LID can not solve the problem of urban flood and waterlogging. Except for a series of LID measures during the process of SCC, corresponding control scheme of river-lake system should be established to realize water-related targets. From the view of ecological sponge basin, this study presents the general idea of SCC both in and out of the unban built-up area and the corresponding control scheme of river-lake system: for the regions outside the built-up area, the main aim of SCC is to carry out the top-level design of urban flood control and waterlogging, establish the water security system outside the city for solving the problems including flood control, water resources, water environment and water ecology; for the built-up area, the main aim of SCC is to construct different kinds of urban sponge according to local conditions and develop multi-scale drainage system responding to different intensities of rainfall taking the river-lake system as the core. Taking Fenghuang County of Hunan Province as an example for the application research, the results indicate that, after the implementation of the control scheme of river-lake system: 1) together with other SCC measures including LID, the control rate of total annual runoff in Fenghuang County is expected to be 82.9% which meets the target requirement of 80%; 2) flood control and drainage standards in Fenghuang County can be increased from the current 10-year return to 20-year return; 3) urban and rural water supply guarantee rate is expected to be 98% which meets the target requirement of 95%. Therefore, the control scheme of urban river-lake system in the county is technically feasible, and can effectively solve the problems including flood control, water resources shortage and ecological water demand in the county, thus may provide strong support and guarantee for SCC.

Magsat attitude dynamics and control: Some observations and explanations

NASA Technical Reports Server (NTRS)

Stengle, T. H.

1980-01-01

Before its reentry 7 months after launch, Magsat transmitted an abundance of valuable data for mapping the Earth's magnetic field. As an added benefit, a wealth of attitude data for study by spacecraft dynamicists was also collected. Because of its unique configuration, Magsat presented new control problems. With its aerodynamic trim boom, attitude control was given an added dimension. Minimization of attitude drift, which could be mapped in relative detail, became the goal. Momentum control, which was accomplished by pitching the spacecraft in order to balance aerodynamic and gravity gradient torques, was seldom difficult to achieve. Several interesting phenomena observed as part of this activity included occasional momentum wheel instability and a rough correlation between solar flux and the pitch angle required to maintain acceptable momentum. An overview is presented of the attitude behavior of Magsat and some of the control problems encountered. Plausible explanations for some of this behavior are offered. Some of the control philosophy used during the mission is examined and aerodynamic trimming operations are summarized.

Child behavior check list and Korean personality inventory for children with functional visual loss.

PubMed

Kyung, Sung Eun; Lee, Sang Mi; Lim, Myung Ho

2014-08-01

To investigate the clinical psychiatric characteristics of children with the main complaint of functional visual loss, their behavior and personality were evaluated by the means of the Korean child behavior check list (K-CBCL), and the Korean personality inventory for children (KPI-C). The evaluation was carried out by the K-CBCL and the KPI-C, the domestically standardized tools, with 20 child subjects suspected of functional visual loss, among the patients who visited our hospital, between August, 2005 and December, 2012. The control group included 160 children in general schools of the same region. The 20 patients whose main complaint was functional visual loss were diagnosed as having a functional visual disorder. The child patient group showed a higher score for the K-CBCL and KPI-C sub-scales of somatic complaints, social problems, aggressive behavior, internalizing problems, externalizing problems, total behavioral problems, somatization and hyperactivity, than that of the control group. The results of the K-CBCL and KPI-C tests among children with functional visual loss, were significantly different from those of the normal control group. This result suggested that psychological factors may influence children with a main complaint of functional visual loss.

Automation of multi-agent control for complex dynamic systems in heterogeneous computational network

NASA Astrophysics Data System (ADS)

Oparin, Gennady; Feoktistov, Alexander; Bogdanova, Vera; Sidorov, Ivan

2017-01-01

The rapid progress of high-performance computing entails new challenges related to solving large scientific problems for various subject domains in a heterogeneous distributed computing environment (e.g., a network, Grid system, or Cloud infrastructure). The specialists in the field of parallel and distributed computing give the special attention to a scalability of applications for problem solving. An effective management of the scalable application in the heterogeneous distributed computing environment is still a non-trivial issue. Control systems that operate in networks, especially relate to this issue. We propose a new approach to the multi-agent management for the scalable applications in the heterogeneous computational network. The fundamentals of our approach are the integrated use of conceptual programming, simulation modeling, network monitoring, multi-agent management, and service-oriented programming. We developed a special framework for an automation of the problem solving. Advantages of the proposed approach are demonstrated on the parametric synthesis example of the static linear regulator for complex dynamic systems. Benefits of the scalable application for solving this problem include automation of the multi-agent control for the systems in a parallel mode with various degrees of its detailed elaboration.

Finite-Time and Fixed-Time Cluster Synchronization With or Without Pinning Control.

PubMed

Liu, Xiwei; Chen, Tianping

2018-01-01

In this paper, the finite-time and fixed-time cluster synchronization problem for complex networks with or without pinning control are discussed. Finite-time (or fixed-time) synchronization has been a hot topic in recent years, which means that the network can achieve synchronization in finite-time, and the settling time depends on the initial values for finite-time synchronization (or the settling time is bounded by a constant for any initial values for fixed-time synchronization). To realize the finite-time and fixed-time cluster synchronization, some simple distributed protocols with or without pinning control are designed and the effectiveness is rigorously proved. Several sufficient criteria are also obtained to clarify the effects of coupling terms for finite-time and fixed-time cluster synchronization. Especially, when the cluster number is one, the cluster synchronization becomes the complete synchronization problem; when the network has only one node, the coupling term between nodes will disappear, and the synchronization problem becomes the simplest master-slave case, which also includes the stability problem for nonlinear systems like neural networks. All these cases are also discussed. Finally, numerical simulations are presented to demonstrate the correctness of obtained theoretical results.

Effects of Smart-Tablet-Based Neurofeedback Training on Cognitive Function in Children with Attention Problems.

PubMed

Shin, Min-Sup; Jeon, Hyejin; Kim, Miyoung; Hwang, Taeho; Oh, Seo Jin; Hwangbo, Minsu; Kim, Ki Joong

2016-05-01

We sought to determine whether smart-tablet-based neurofeedback could improve executive function-including attention, working memory, and self-regulation-in children with attention problems. Forty children (10-12 years old) with attention problems, as determined by ratings on the Conners Parent Rating Scale, were assigned to either a neurofeedback group that received 16 sessions or a control group. A comprehensive test battery that assessed general intelligence, visual and auditory attention, attentional shifting, response inhibition and behavior rating scales were administered to both groups before neurofeedback training. Several neuropsychological tests were conducted at posttraining and follow-up assessment. Scores on several neuropsychological tests and parent behavior rating scales showed significant improvement in the training group but not in the controls. The improvements remained through the follow-up assessment. This study suggests that the smart-tablet-based neurofeedback training program might improve cognitive function in children with attention problems. © The Author(s) 2015.

Alcohol marketing, drunkenness, and problem drinking among Zambian youth: findings from the 2004 Global School-Based Student Health Survey.

PubMed

Swahn, Monica H; Ali, Bina; Palmier, Jane B; Sikazwe, George; Mayeya, John

2011-01-01

This study examines the associations between alcohol marketing strategies, alcohol education including knowledge about dangers of alcohol and refusal of alcohol, and drinking prevalence, problem drinking, and drunkenness. Analyses are based on the Global School-Based Student Health Survey (GSHS) conducted in Zambia (2004) of students primarily 11 to 16 years of age (N = 2257). Four statistical models were computed to test the associations between alcohol marketing and education and alcohol use, while controlling for possible confounding factors. Alcohol marketing, specifically through providing free alcohol through a company representative, was associated with drunkenness (AOR = 1.49; 95% CI: 1.09-2.02) and problem drinking (AOR = 1.41; 95% CI: 1.06-1.87) among youth after controlling for demographic characteristics, risky behaviors, and alcohol education. However, alcohol education was not associated with drunkenness or problem drinking. These findings underscore the importance of restricting alcohol marketing practices as an important policy strategy for reducing alcohol use and its dire consequences among vulnerable youth.

Prunus rootstocks

USDA-ARS?s Scientific Manuscript database

New clonal Prunus hybrid rootstocks for apricot and plums offer improved adaptation to site related problems including soil borne diseases, waterlogging, calcareous soils and various species of nematodes. Additionally, they offer varying degrees of vigor control compared to standard seedling and clo...

Thermal Control System for a Small, Extended Duration Lunar Surface Science Platform

NASA Technical Reports Server (NTRS)

Bugby, D.; Farmer, J.; OConnor, B.; Wirzburger, M.; Abel, E.; Stouffer, C.

2010-01-01

The presentation slides include: Introduction: lunar mission definition, Problem: requirements/methodology, Concept: thermal switching options, Analysis: system evaluation, Plans: dual-radiator LHP (loop heat pipe) test bed, and Conclusions: from this study.

Identification and feedback control in structures with piezoceramic actuators

NASA Technical Reports Server (NTRS)

Banks, H. T.; Ito, K.; Wang, Y.

1992-01-01

In this lecture we give fundamental well-posedness results for a variational formulation of a class of damped second order partial differential equations with unbounded input or control coefficients. Included as special cases in this class are structures with piezoceramic actuators. We consider approximation techniques leading to computational methods in the context of both parameter estimation and feedback control problems for these systems. Rigorous convergence results for parameter estimates and feedback gains are discussed.

Application of Design Methodologies for Feedback Compensation Associated with Linear Systems

NASA Technical Reports Server (NTRS)

Smith, Monty J.

1996-01-01

The work that follows is concerned with the application of design methodologies for feedback compensation associated with linear systems. In general, the intent is to provide a well behaved closed loop system in terms of stability and robustness (internal signals remain bounded with a certain amount of uncertainty) and simultaneously achieve an acceptable level of performance. The approach here has been to convert the closed loop system and control synthesis problem into the interpolation setting. The interpolation formulation then serves as our mathematical representation of the design process. Lifting techniques have been used to solve the corresponding interpolation and control synthesis problems. Several applications using this multiobjective design methodology have been included to show the effectiveness of these techniques. In particular, the mixed H 2-H performance criteria with algorithm has been used on several examples including an F-18 HARV (High Angle of Attack Research Vehicle) for sensitivity performance.

Risky dieting amongst adolescent girls: Associations with family relationship problems and depressed mood.

PubMed

Hinchliff, Gemma L M; Kelly, Adrian B; Chan, Gary C K; Patton, George C; Williams, Joanne

2016-08-01

This study examined the association of risky dieting amongst adolescent girls with depressed mood, family conflict, and parent-child emotional closeness. Grade 6 and 8 females (aged 11-14years, N=4031) were recruited from 231 schools in 30 communities, across three Australian States (Queensland, Victoria, and Western Australia). Key measures were based on the Adolescent Dieting Scale, Short Mood and Feelings Questionnaire, and widely used short measures of family relationship quality. Controls included age, early pubertal onset, and socioeconomic status. Risky dieting was significantly related to family conflict and depressed mood, depressed mood mediated the association of family conflict and risky dieting, and these associations remained significant with controls in the model. Family conflict and adolescent depressed mood are associated with risky dieting. Prevention programs may benefit from a broadening of behavioural targets to include depressed mood and family problems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prediction of clinical depression scores and detection of changes in whole-brain using resting-state functional MRI data with partial least squares regression

PubMed Central

Shimizu, Yu; Yoshimoto, Junichiro; Takamura, Masahiro; Okada, Go; Okamoto, Yasumasa; Yamawaki, Shigeto; Doya, Kenji

2017-01-01

In diagnostic applications of statistical machine learning methods to brain imaging data, common problems include data high-dimensionality and co-linearity, which often cause over-fitting and instability. To overcome these problems, we applied partial least squares (PLS) regression to resting-state functional magnetic resonance imaging (rs-fMRI) data, creating a low-dimensional representation that relates symptoms to brain activity and that predicts clinical measures. Our experimental results, based upon data from clinically depressed patients and healthy controls, demonstrated that PLS and its kernel variants provided significantly better prediction of clinical measures than ordinary linear regression. Subsequent classification using predicted clinical scores distinguished depressed patients from healthy controls with 80% accuracy. Moreover, loading vectors for latent variables enabled us to identify brain regions relevant to depression, including the default mode network, the right superior frontal gyrus, and the superior motor area. PMID:28700672

Animal-Assisted Therapies for Youth with or at risk for Mental Health Problems: A Systematic Review.

PubMed

Hoagwood, Kimberly Eaton; Acri, Mary; Morrissey, Meghan; Peth-Pierce, Robin

2017-01-01

To systematically review experimental evidence about animal-assisted therapies (AAT) for children or adolescents with or at risk for mental health conditions, we reviewed all experimental AAT studies published between 2000-2015, and compared studies by animal type, intervention, and outcomes. Studies were included if used therapeutically for children and adolescents (≤21 years) with or at risk for a mental health problem; used random assignment or a waitlist comparison/control group; and included child-specific outcome data. Of 1,535 studies, 24 met inclusion criteria. Of 24 studies identified, almost half were randomized controlled trials, with 9 of 11 published in the past two years. The largest group addresses equine therapies for autism. Findings are generally promising for positive effects associated with equine therapies for autism and canine therapies for childhood trauma. The AAT research base is slim; a more focused research agenda is outlined.

Hypersonic vehicle model and control law development using H(infinity) and micron synthesis

NASA Astrophysics Data System (ADS)

Gregory, Irene M.; Chowdhry, Rajiv S.; McMinn, John D.; Shaughnessy, John D.

1994-10-01

The control system design for a Single Stage To Orbit (SSTO) air breathing vehicle will be central to a successful mission because a precise ascent trajectory will preserve narrow payload margins. The air breathing propulsion system requires the vehicle to fly roughly halfway around the Earth through atmospheric turbulence. The turbulence, the high sensitivity of the propulsion system to inlet flow conditions, the relatively large uncertainty of the parameters characterizing the vehicle, and continuous acceleration make the problem especially challenging. Adequate stability margins must be provided without sacrificing payload mass since payload margins are critical. Therefore, a multivariable control theory capable of explicitly including both uncertainty and performance is needed. The H(infinity) controller in general provides good robustness but can result in conservative solutions for practical problems involving structured uncertainty. Structured singular value mu framework for analysis and synthesis is potentially much less conservative and hence more appropriate for problems with tight margins. An SSTO control system requires: highly accurate tracking of velocity and altitude commands while limiting angle-of-attack oscillations, minimized control power usage, and a stabilized vehicle when atmospheric turbulence and system uncertainty are present. The controller designs using H(infinity) and mu-synthesis procedures were compared. An integrated flight/propulsion dynamic mathematical model of a conical accelerator vehicle was linearized as the vehicle accelerated through Mach 8. Vehicle acceleration through the selected flight condition gives rise to parametric variation that was modeled as a structured uncertainty. The mu-analysis approach was used in the frequency domain to conduct controller analysis and was confirmed by time history plots. Results demonstrate the inherent advantages of the mu framework for this class of problems.

Hypersonic vehicle model and control law development using H(infinity) and micron synthesis

NASA Technical Reports Server (NTRS)

Gregory, Irene M.; Chowdhry, Rajiv S.; Mcminn, John D.; Shaughnessy, John D.

1994-01-01

The control system design for a Single Stage To Orbit (SSTO) air breathing vehicle will be central to a successful mission because a precise ascent trajectory will preserve narrow payload margins. The air breathing propulsion system requires the vehicle to fly roughly halfway around the Earth through atmospheric turbulence. The turbulence, the high sensitivity of the propulsion system to inlet flow conditions, the relatively large uncertainty of the parameters characterizing the vehicle, and continuous acceleration make the problem especially challenging. Adequate stability margins must be provided without sacrificing payload mass since payload margins are critical. Therefore, a multivariable control theory capable of explicitly including both uncertainty and performance is needed. The H(infinity) controller in general provides good robustness but can result in conservative solutions for practical problems involving structured uncertainty. Structured singular value mu framework for analysis and synthesis is potentially much less conservative and hence more appropriate for problems with tight margins. An SSTO control system requires: highly accurate tracking of velocity and altitude commands while limiting angle-of-attack oscillations, minimized control power usage, and a stabilized vehicle when atmospheric turbulence and system uncertainty are present. The controller designs using H(infinity) and mu-synthesis procedures were compared. An integrated flight/propulsion dynamic mathematical model of a conical accelerator vehicle was linearized as the vehicle accelerated through Mach 8. Vehicle acceleration through the selected flight condition gives rise to parametric variation that was modeled as a structured uncertainty. The mu-analysis approach was used in the frequency domain to conduct controller analysis and was confirmed by time history plots. Results demonstrate the inherent advantages of the mu framework for this class of problems.

Childhood self-control and adult outcomes: results from a 30-year longitudinal study.

PubMed

Fergusson, David M; Boden, Joseph M; Horwood, L John

2013-07-01

A study by Moffitt et al. reported pervasive associations between childhood self-control and adult outcomes. The current study attempts to replicate the findings reported by Moffitt et al., adjusting these results for the confounding influence of childhood conduct problems. Data were gathered from the Christchurch Health and Development Study, a longitudinal birth cohort studied to age 30 years. Self-control during ages 6 to 12 years was measured analogously to that in Moffitt et al., using parent-, teacher-, and self-report methods. Outcome measures to age 30 included criminal offending, substance use, education/employment, sexual behavior, and mental health. Associations between self-control and outcomes were adjusted for possible confounding by gender, socioeconomic status (SES), IQ, and childhood conduct problems (ages 6-10). In confirmation of the findings of Moffitt et al., all outcomes except major depression were significantly (p < .05) associated with childhood self-control. Adjustment for gender, SES, and IQ reduced to some extent the magnitude of the associations. However, adjustment for childhood conduct disorder further reduced the magnitude of many of these associations, with only 4 of the 14 outcomes remaining statistically significantly (p < .05) associated with self-control. After adjustment for gender, SES, IQ, and conduct problems, those individuals who scored higher in self-control had lower odds of violent offending and welfare dependence, were more likely to have obtained a university degree, and had higher income levels. The findings from this study suggest that observed linkages between a measure of childhood self-control and outcomes in adulthood were largely explained by the correlated effects of childhood conduct problems, SES, IQ, and gender. Copyright © 2013 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

The influence of television and video game use on attention and school problems: a multivariate analysis with other risk factors controlled.

PubMed

Ferguson, Christopher J

2011-06-01

Research on youth mental health has increasingly indicated the importance of multivariate analyses of multiple risk factors for negative outcomes. Television and video game use have often been posited as potential contributors to attention problems, but previous studies have not always been well-controlled or used well-validated outcome measures. The current study examines the multivariate nature of risk factors for attention problems symptomatic of attention deficit hyperactivity disorder and poor school performance. A predominantly Hispanic population of 603 children (ages 10-14) and their parents/guardians responded to multiple behavioral measures. Outcome measures included parent and child reported attention problem behaviors on the Child Behavior Checklist (CBCL) as well as poor school performance as measured by grade point average (GPA). Results found that internal factors such as male gender, antisocial traits, family environment and anxiety best predicted attention problems. School performance was best predicted by family income. Television and video game use, whether total time spent using, or exposure to violent content specifically, did not predict attention problems or GPA. Television and video game use do not appear to be significant predictors of childhood attention problems. Intervention and prevention efforts may be better spent on other risk factors. Copyright © 2010 Elsevier Ltd. All rights reserved.

A Novel Piggyback Selection Scheme in IEEE 802.11e HCCA

NASA Astrophysics Data System (ADS)

Lee, Hyun-Jin; Kim, Jae-Hyun

A control frame can be piggybacked onto a data frame to increase channel efficiency in wireless communication. However, if the control frame including global control information is piggybacked, the delay of the data frame from a access point will be increased even though there is only one station with low physical transmission rate. It is similar to the anomaly phenomenon in a network which supports multi-rate transmission. In this letter, we define this phenomenon as “the piggyback problem at low physical transmission rate” and evaluate the effect of this problem with respect to physical transmission rate and normalized traffic load. Then, we propose a delay-based piggyback scheme. Simulations show that the proposed scheme reduces average frame transmission delay and improves channel utilization about 24% and 25%, respectively.

European Scientific Notes, Volume 37, Number 3,

DTIC Science & Technology

1983-03-31

aircraft, in- cluding two at JFK Airport in New York. Thus, there was a worldwide motivation to explore the air-safety aspects of unexpected...implies that no tour can be longer than n times the length of an optimal tour. Maffioli has recently applied his work to problems related to the...results are being applied to a wide variety of problems, including control of ships, helicopters, house heating , and electrical power loads. There

An Intervention Including an Online Game to Improve Grade 6 Students' Performance in Early Algebra

ERIC Educational Resources Information Center

Kolovou, Angeliki; van den Heuvel-Panhuizen, Marja; Koller, Olaf

2013-01-01

This study investigated whether an intervention including an online game contributed to 236 Grade 6 students' performance in early algebra, that is, solving problems with covarying quantities. An exploratory quasi-experimental study was conducted with a pretest-posttest-control-group design. Students in the experimental group were asked to solve…

Approach path control for powered-lift STOL aircraft

NASA Technical Reports Server (NTRS)

Clymer, D. J.; Flora, C. C.

1973-01-01

A flight control system concept is defined for approach flightpath control of an augmentor wing (or similar) powered-lift STOL configuration. The proposed STOL control concept produces aircraft transient and steady-state control responses that are familiar to pilots of conventional jet transports, and has potential for good handling qualities ratings in all approach and landing phases. The effects of trailing-edge rate limits, real-engine dynamics, and atmospheric turbulence are considered in the study. A general discussion of STOL handling qualities problems and piloting techniques is included.

Precedent approach to the formation of programs for cyclic objects control

NASA Astrophysics Data System (ADS)

Kulakov, S. M.; Trofimov, V. B.; Dobrynin, A. S.; Taraborina, E. N.

2018-05-01

The idea and procedure for formalizing the precedent method of formation of complex control solutions (complex control programs) is discussed with respect to technological or organizational objects, the operation of which is organized cyclically. A typical functional structure of the system of precedent control by complex technological unit is developed, including a subsystem of retrospective optimization of actually implemented control programs. As an example, the problem of constructing replaceable planograms for the operation of the link of a heading-and-winning machine on the basis of precedents is considered.

Handbook for industrial noise control

NASA Technical Reports Server (NTRS)

1981-01-01

The basic principles of sound, measuring techniques, and instrumentation associated with general purpose noise control are discussed. Means for identifying and characterizing a noise problem so that subsequent work may provide the most efficient and cost effective solution are outlined. A methodology for choosing appropriate noise control materials and the proper implementation of control procedures is detailed. The most significant NASA sponsored contributions to the state of the art development of optimum noise control technologies are described including cases in which aeroacoustics and related research have shed some light on ways of reducing noise generation at its source.

Handbook for industrial noise control

NASA Astrophysics Data System (ADS)

The basic principles of sound, measuring techniques, and instrumentation associated with general purpose noise control are discussed. Means for identifying and characterizing a noise problem so that subsequent work may provide the most efficient and cost effective solution are outlined. A methodology for choosing appropriate noise control materials and the proper implementation of control procedures is detailed. The most significant NASA sponsored contributions to the state of the art development of optimum noise control technologies are described including cases in which aeroacoustics and related research have shed some light on ways of reducing noise generation at its source.

Using new aggregation operators in rule-based intelligent control

NASA Technical Reports Server (NTRS)

Berenji, Hamid R.; Chen, Yung-Yaw; Yager, Ronald R.

1990-01-01

A new aggregation operator is applied in the design of an approximate reasoning-based controller. The ordered weighted averaging (OWA) operator has the property of lying between the And function and the Or function used in previous fuzzy set reasoning systems. It is shown here that, by applying OWA operators, more generalized types of control rules, which may include linguistic quantifiers such as Many and Most, can be developed. The new aggregation operators, as tested in a cart-pole balancing control problem, illustrate improved performance when compared with existing fuzzy control aggregation schemes.

Understanding sleep problems in children with epilepsy: Associations with quality of life, Attention-Deficit Hyperactivity Disorder and maternal emotional symptoms.

PubMed

Ekinci, Ozalp; Isik, Uğur; Gunes, Serkan; Ekinci, Nuran

2016-08-01

This study aimed to (1) compare sleep problems between children and adolescents with epilepsy and non-epileptic controls, and (2) examine whether there is an association between sleep problems and quality of life, Attention-Deficit Hyperactivity Disorder (ADHD) and mothers' emotional symptoms. Fifty-three patients from a cohort of epilepsy (aged 7-18 years) and 28 controls with minor medical problems (aged 7-18 years) were included. Parents completed Children's Sleep Habits Questionnaire (CSHQ) and Kinder Lebensqualitätsfragebogen: Children's Quality of Life Questionnaire-revised (KINDL-R) for patients and controls. Turgay DSM-IV Disruptive Behavior Disorders Rating Scale (T-DSM-IV-S) parent and teacher forms were used to assess ADHD symptoms for patients. Mothers of the patients completed Beck Depression Inventory and State-Trait Anxiety Inventory (STAI). Neurology clinic charts were reviewed for the epilepsy-related variables. Children with epilepsy had a higher CSHQ Total score than the control group. Those with a CSHQ score >56 (which indicates moderate to severe sleep problems) had lower scores on KINDL-R. Parent-rated T-DSM-IV-S Total and Hyperactivity-Impulsivity scores, STAI trait and Beck scores were found to be higher in those with a CSHQ score >56. Significant positive correlations were found between CSHQ Total score and T-DSM-IV-S, STAI trait and Beck scores. Binary logistic regression analysis revealed that T-DSM-IV-S Total, Inattention and Hyperactivity-Impulsivity scores were significantly associated with a higher CSHQ Total score. None of the epilepsy-related variables were found to be related with the CSHQ Total score. Among children with epilepsy, sleep problems lead to a poor quality of life. The link between sleep problems and psychiatric symptoms must be conceptualized as a bilateral relationship. ADHD appears to be the strongest predictor of sleep problems. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

International Telecommunication Control: International Law and the Ordering of Satellite and Other Forms of International Broadcasting.

ERIC Educational Resources Information Center

Smith, Delbert D.

The need for and the available alternatives for international telecommunication controls are examined, and a functional approach to this area of law is offered. Information from a number of areas is collected and examined as it relates to the basic problem. These areas include general principles of international law, the activities of the…

International Federation of Library Associations Annual Conference Papers. Bibliographic Control Division: Bibliography and Cataloguing Sections (47th, Leipzig, East Germany, August 17-22, 1981).

ERIC Educational Resources Information Center

Vita, Susan H.; And Others

This set of papers delivered to the Bibliographic Control Division of the International Federation of Library Associations (IFLA) during its 47th annual conference (1981) includes: "Cataloging in Publication in the United States--Problems and Prospects," by Susan H. Vita; "Development and Coordination of Bibliographic Activities:…

Input filter compensation for switching regulators

NASA Technical Reports Server (NTRS)

Lee, F. C.

1984-01-01

Problems caused by input filter interaction and conventional input filter design techniques are discussed. The concept of feedforward control is modeled with an input filter and a buck regulator. Experimental measurement and comparison to the analytical predictions is carried out. Transient response and the use of a feedforward loop to stabilize the regulator system is described. Other possible applications for feedforward control are included.

Sycamore Pests: A Guide to Major Insects, Diseases, and Air Pollution

Treesearch

T. H. Filer; J. D. Solomon; F. I. McCracken; F. L. Oliveria; R. Lewis; M. J. Weiss; T. J. Rogers

1977-01-01

This booklet will help nurserymen, forest woodland managers and homeowners to identify and control pest problems. Major insects and diseases are illustrated. Brief mention is made of other pests of local or sporadic concern. A list of registered chemical controls is included. This list is subject to change as new chemicals are approved. Revisions will be made available...

Practical optimal flight control system design for helicopter aircraft. Volume 2: Software user's guide

NASA Technical Reports Server (NTRS)

Riedel, S. A.

1979-01-01

A method by which modern and classical control theory techniques may be integrated in a synergistic fashion and used in the design of practical flight control systems is presented. A general procedure is developed, and several illustrative examples are included. Emphasis is placed not only on the synthesis of the design, but on the assessment of the results as well. The first step is to establish the differences, distinguishing characteristics and connections between the modern and classical control theory approaches. Ultimately, this uncovers a relationship between bandwidth goals familiar in classical control and cost function weights in the equivalent optimal system. In order to obtain a practical optimal solution, it is also necessary to formulate the problem very carefully, and each choice of state, measurement and output variable must be judiciously considered. Once design goals are established and problem formulation completed, the control system is synthesized in a straightforward manner. Three steps are involved: filter-observer solution, regulator solution, and the combination of those two into the controller. Assessment of the controller permits and examination and expansion of the synthesis results.

Results of an integrated structure/control law design sensitivity analysis

NASA Technical Reports Server (NTRS)

Gilbert, Michael G.

1989-01-01

A design sensitivity analysis method for Linear Quadratic Cost, Gaussian (LQG) optimal control laws, which predicts change in the optimal control law due to changes in fixed problem parameters using analytical sensitivity equations is discussed. Numerical results of a design sensitivity analysis for a realistic aeroservoelastic aircraft example are presented. In this example, the sensitivity of the optimally controlled aircraft's response to various problem formulation and physical aircraft parameters is determined. These results are used to predict the aircraft's new optimally controlled response if the parameter was to have some other nominal value during the control law design process. The sensitivity results are validated by recomputing the optimal control law for discrete variations in parameters, computing the new actual aircraft response, and comparing with the predicted response. These results show an improvement in sensitivity accuracy for integrated design purposes over methods which do not include changes in the optimal control law. Use of the analytical LQG sensitivity expressions is also shown to be more efficient than finite difference methods for the computation of the equivalent sensitivity information.

Analysis of explicit model predictive control for path-following control

PubMed Central

2018-01-01

In this paper, explicit Model Predictive Control(MPC) is employed for automated lane-keeping systems. MPC has been regarded as the key to handle such constrained systems. However, the massive computational complexity of MPC, which employs online optimization, has been a major drawback that limits the range of its target application to relatively small and/or slow problems. Explicit MPC can reduce this computational burden using a multi-parametric quadratic programming technique(mp-QP). The control objective is to derive an optimal front steering wheel angle at each sampling time so that autonomous vehicles travel along desired paths, including straight, circular, and clothoid parts, at high entry speeds. In terms of the design of the proposed controller, a method of choosing weighting matrices in an optimization problem and the range of horizons for path-following control are described through simulations. For the verification of the proposed controller, simulation results obtained using other control methods such as MPC, Linear-Quadratic Regulator(LQR), and driver model are employed, and CarSim, which reflects the features of a vehicle more realistically than MATLAB/Simulink, is used for reliable demonstration. PMID:29534080

Analysis of explicit model predictive control for path-following control.

PubMed

Lee, Junho; Chang, Hyuk-Jun

2018-01-01

In this paper, explicit Model Predictive Control(MPC) is employed for automated lane-keeping systems. MPC has been regarded as the key to handle such constrained systems. However, the massive computational complexity of MPC, which employs online optimization, has been a major drawback that limits the range of its target application to relatively small and/or slow problems. Explicit MPC can reduce this computational burden using a multi-parametric quadratic programming technique(mp-QP). The control objective is to derive an optimal front steering wheel angle at each sampling time so that autonomous vehicles travel along desired paths, including straight, circular, and clothoid parts, at high entry speeds. In terms of the design of the proposed controller, a method of choosing weighting matrices in an optimization problem and the range of horizons for path-following control are described through simulations. For the verification of the proposed controller, simulation results obtained using other control methods such as MPC, Linear-Quadratic Regulator(LQR), and driver model are employed, and CarSim, which reflects the features of a vehicle more realistically than MATLAB/Simulink, is used for reliable demonstration.

The effectiveness of return-to-work interventions that incorporate work-focused problem-solving skills for workers with sickness absences related to mental disorders: a systematic literature review.

PubMed

Dewa, Carolyn S; Loong, Desmond; Bonato, Sarah; Joosen, Margot C W

2015-06-15

This paper reviews the current state of the published peer-reviewed literature related to return-to-work (RTW) interventions that incorporate work-related problem-solving skills for workers with sickness absences related to mental disorders. It addresses the question: What is the evidence for the effectiveness of these RTW interventions? Using a multiphase screening process, this systematic literature review was based on publically available peer-reviewed studies. Five electronic databases were searched: (1) Medline Current, (2) Medline In-process, (3) PsycINFO, (4) Econlit and (5) Web of Science. The focus was on RTW interventions for workers with medically certified sickness absences related to mental disorders. Workers with medically certified sickness absences related to mental disorders. RTW intervention included work-focused problem-solving skills. RTW rates and length of sickness absences. There were 4709 unique citations identified. Of these, eight articles representing a total of six studies were included in the review. In terms of bias avoidance, two of the six studies were rated as excellent, two as good and two as weak. Five studies were from the Netherlands; one was from Norway. There was variability among the studies with regard to RTW findings. Two of three studies reported significant differences in RTW rates between the intervention and control groups. One of six studies observed a significant difference in sickness absence duration between intervention and control groups. There is limited evidence that combinations of interventions that include work-related problem-solving skills are effective in RTW outcomes. The evidence could be strengthened if future studies included more detailed examinations of intervention adherence and changes in problem-solving skills. Future studies should also examine the long-term effects of problem-solving skills on sickness absence recurrence and work productivity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Naturally selecting solutions: the use of genetic algorithms in bioinformatics.

PubMed

Manning, Timmy; Sleator, Roy D; Walsh, Paul

2013-01-01

For decades, computer scientists have looked to nature for biologically inspired solutions to computational problems; ranging from robotic control to scheduling optimization. Paradoxically, as we move deeper into the post-genomics era, the reverse is occurring, as biologists and bioinformaticians look to computational techniques, to solve a variety of biological problems. One of the most common biologically inspired techniques are genetic algorithms (GAs), which take the Darwinian concept of natural selection as the driving force behind systems for solving real world problems, including those in the bioinformatics domain. Herein, we provide an overview of genetic algorithms and survey some of the most recent applications of this approach to bioinformatics based problems.

[A strategy of constructing the technological system for quality control of Chinese medicine based on process control and management].

PubMed

Cheng, Yi-Yu; Qian, Zhong-Zhi; Zhang, Bo-Li

2017-01-01

The current situation, bottleneck problems and severe challenges in quality control technology of Chinese Medicine (CM) are briefly described. It is presented to change the phenomenon related to the post-test as the main means and contempt for process control in drug regulation, reverse the situation of neglecting the development of process control and management technology for pharmaceutical manufacture and reconstruct the technological system for quality control of CM products. The regulation and technology system based on process control and management for controlling CM quality should be established to solve weighty realistic problems of CM industry from the root causes, including backwardness of quality control technology, weakness of quality risk control measures, poor reputation of product quality and so on. By this way, the obstacles from poor controllability of CM product quality could be broken. Concentrating on those difficult problems and weak links in the technical field of CM quality control, it is proposed to build CMC (Chemistry, Manufacturing and Controls) regulation for CM products with Chinese characteristics and promote the regulation international recognition as soon as possible. The CMC technical framework, which is clinical efficacy-oriented, manufacturing manner-centered and process control-focused, was designed. To address the clinical characteristics of traditional Chinese medicine (TCM) and the production feature of CM manufacture, it is suggested to establish quality control engineering for CM manufacturing by integrating pharmaceutical analysis, TCM chemistry, TCM pharmacology, pharmaceutical engineering, control engineering, management engineering and other disciplines. Further, a theoretical model of quality control engineering for CM manufacturing and the methodology of digital pharmaceutical engineering are proposed. A technology pathway for promoting CM standard and realizing the strategic goal of CM internationalization is elaborated. Copyright© by the Chinese Pharmaceutical Association.

Lessons learned from Shuttle/Mir: psychosocial countermeasures

NASA Technical Reports Server (NTRS)

Kanas, Nick; Salnitskiy, Vyacheslav; Grund, Ellen M.; Gushin, Vadim; Weiss, Daniel S.; Kozerenko, Olga; Sled, Alexander; Marmar, Charles R.

2002-01-01

BACKGROUND: During future long-duration space missions, countermeasures need to be developed to deal with psychosocial issues that might impact negatively on crewmember performance and well-being. METHODS: In our recently completed NASA-funded study of 5 U.S. astronauts, 8 Russian cosmonauts, and 42 U.S. and 16 Russian mission control personnel who participated in the Shuttle/Mir program, we evaluated a number of important psychosocial issues such as group tension, cohesion, leadership role, and the displacement of negative emotions from crewmembers to people in mission control and from mission control personnel to management. RESULTS: Based on our findings, which are reviewed, a number of psychosocial countermeasures are suggested to help ameliorate the negative impact of potential psychosocial problems during future manned space missions. CONCLUSIONS: Crewmembers should be selected not only to rule out psychopathology but also to select-in for group compatibility and facility in a common language. Training should include briefings and team building related to a number of psychosocial issues and should involve both crewmembers and mission control personnel. During the mission, both experts on the ground and the crewmembers themselves should be alert to potential interpersonal problems, including the displacement of negative emotions from the crew to the ground. Supportive activities should consist of both individual and interpersonal strategies, including an awareness of changing leisure time needs. Finally, attention should be given to postmission readjustment and to supporting the families on Earth.

Therapeutic perspectives in hypertension: novel means for renin-angiotensin-aldosterone system modulation and emerging device-based approaches.

PubMed

Unger, Thomas; Paulis, Ludovit; Sica, Domenic A

2011-11-01

The conventional antihypertensive therapies including renin-angiotensin-aldosterone system antagonists (converting enzyme inhibitors, receptor blockers, renin inhibitors, and mineralocorticoid receptor blockers), diuretics, β-blockers, and calcium channel blockers are variably successful in achieving the challenging target blood pressure values in hypertensive patients. Difficult to treat hypertension is still a commonly observed problem world-wide. A number of drugs are considered to be used as novel therapies for hypertension. Renalase supplementation, vasopeptidase inhibitors, endothelin antagonists, and especially aldosterone antagonists (aldosterone synthase inhibitors and novel selective mineralocorticoid receptor blockers) are considered an option in resistant hypertension. In addition, the aldosterone antagonists as well as (pro)renin receptor blockers or AT(2) receptor agonists might attenuate end-organ damage. This array of medications has now been complemented by a number of new approaches of non-pharmacological strategies including vaccination, genomic interference, controlled breathing, baroreflex activation, and probably most successfully renal denervation techniques. However, the progress on innovative therapies seems to be slow and the problem of resistant hypertension and proper blood pressure control appears to be still persisting. Therefore the regimens of currently available drugs are being fine-tuned, resulting in the establishment of several novel fixed-dose combinations including triple combinations with the aim to facilitate proper blood pressure control. It remains an exciting question which approach will confer the best blood pressure control and risk reduction in this tricky disease.

The flying hot wire and related instrumentation

NASA Technical Reports Server (NTRS)

Coles, D.; Cantnell, B.; Wadcock, A.

1978-01-01

A flying hot-wire technique is proposed for studies of separated turbulent flow in wind tunnels. The technique avoids the problem of signal rectification in regions of high turbulence level by moving the probe rapidly through the flow on the end of a rotating arm. New problems which arise include control of effects of torque variation on rotor speed, avoidance of interference from the wake of the moving arms, and synchronization of data acquisition with rotation. Solutions for these problems are described. The self-calibrating feature of the technique is illustrated by a sample X-array calibration.

Numerical approximation for the infinite-dimensional discrete-time optimal linear-quadratic regulator problem

NASA Technical Reports Server (NTRS)

Gibson, J. S.; Rosen, I. G.

1986-01-01

An abstract approximation framework is developed for the finite and infinite time horizon discrete-time linear-quadratic regulator problem for systems whose state dynamics are described by a linear semigroup of operators on an infinite dimensional Hilbert space. The schemes included the framework yield finite dimensional approximations to the linear state feedback gains which determine the optimal control law. Convergence arguments are given. Examples involving hereditary and parabolic systems and the vibration of a flexible beam are considered. Spline-based finite element schemes for these classes of problems, together with numerical results, are presented and discussed.

The Effectiveness of Art Therapy in Reducing Internalizing and Externalizing Problems of Female Adolescents.

PubMed

Bazargan, Yasaman; Pakdaman, Shahla

2016-01-01

The internalizing and externalizing problems relating to childhood and adolescent have always been significant. Because there is special considerations in establishing communication with them and hence, the therapeutic methods for these problems must take into account these considerations. As establishing a therapeutic relationship is an important component of effective counseling, it seems that art therapy may help alleviate these problems. The purpose of this study is to determine the effectiveness of art therapy in reducing internalizing and externalizing problems of adolescent girls (14 - 18 years old). This is a semi-experimental study carried out in the form of a pre-test/post-test design with control group. The population of this study includes female students of Gole Laleh School of Art in district 3 of Tehran, Iran, out of which 30 students with internalizing problems and 30 individuals with externalizing problems were selected through targeted sampling. Students were randomly assigned to control and experimental groups. Experimental groups participated in 6 painting sessions designed based on Art therapy theories and previous studies. The material used for diagnosis of the problems in posttest and pretest was an Achenbach self-assessment form. Data were analyzed using a mixed analysis of variance (ANOVA). Our results showed that Art therapy significantly reduced internalizing problems (F = 17.61, P < 0.001); however, its effect in reducing externalizing problems was not significant (F = 3.93, P = 0.06). Art therapy as a practical therapeutic method can be used to improve internalizing problems. To reduce externalizing problems, more sessions may be needed. Thus, future studies are required to insure these findings.

Results of an integrated structure-control law design sensitivity analysis

NASA Technical Reports Server (NTRS)

Gilbert, Michael G.

1988-01-01

Next generation air and space vehicle designs are driven by increased performance requirements, demanding a high level of design integration between traditionally separate design disciplines. Interdisciplinary analysis capabilities have been developed, for aeroservoelastic aircraft and large flexible spacecraft control for instance, but the requisite integrated design methods are only beginning to be developed. One integrated design method which has received attention is based on hierarchal problem decompositions, optimization, and design sensitivity analyses. This paper highlights a design sensitivity analysis method for Linear Quadratic Cost, Gaussian (LQG) optimal control laws, which predicts change in the optimal control law due to changes in fixed problem parameters using analytical sensitivity equations. Numerical results of a design sensitivity analysis for a realistic aeroservoelastic aircraft example are presented. In this example, the sensitivity of the optimally controlled aircraft's response to various problem formulation and physical aircraft parameters is determined. These results are used to predict the aircraft's new optimally controlled response if the parameter was to have some other nominal value during the control law design process. The sensitivity results are validated by recomputing the optimal control law for discrete variations in parameters, computing the new actual aircraft response, and comparing with the predicted response. These results show an improvement in sensitivity accuracy for integrated design purposes over methods which do not include changess in the optimal control law. Use of the analytical LQG sensitivity expressions is also shown to be more efficient that finite difference methods for the computation of the equivalent sensitivity information.

Placing invasive species management in a spatiotemporal context.

PubMed

Baker, Christopher M; Bode, Michael

2016-04-01

Invasive species are a worldwide issue, both ecologically and economically. A large body of work focuses on various aspects of invasive species control, including how to allocate control efforts to eradicate an invasive population as cost effectively as possible: There are a diverse range of invasive species management problems, and past mathematical analyses generally focus on isolated examples, making it hard to identify and understand parallels between the different contexts. In this study, we use a single spatiotemporal model to tackle the problem of allocating control effort for invasive species when suppressing an island invasive species, and for long-term spatial suppression projects. Using feral cat suppression as an illustrative example, we identify the optimal resource allocation for island and mainland suppression projects. Our results demonstrate how using a single model to solve different problems reveals similar characteristics of the solutions in different scenarios. As well as illustrating the insights offered by linking problems through a spatiotemporal model, we also derive novel and practically applicable results for our case studies. For temporal suppression projects on islands, we find that lengthy projects are more cost effective and that rapid control projects are only economically cost effective when population growth rates are high or diminishing returns on control effort are low. When suppressing invasive species around conservation assets (e.g., national parks or exclusion fences), we find that the size of buffer zones should depend on the ratio of the species growth and spread rate.

Motivational Interviewing Versus Cognitive Behavioral Group Therapy in the Treatment of Problem and Pathological Gambling: A Randomized Controlled Trial

PubMed Central

Carlbring, Per; Jonsson, Jakob; Josephson, Henrik; Forsberg, Lars

2009-01-01

Pathological gambling is a widespread problem with major implications for society and the individual. There are effective treatments, but little is known about the relative effectiveness of different treatments. The aim of this study was to test the effectiveness of motivational interviewing, cognitive behavioral group therapy, and a no-treatment control (wait-list) in the treatment of pathological gambling. This was done in a randomized controlled trial at an outpatient dependency clinic at Karolinska Institute (Stockholm, Sweden). A total of 150 primarily self-recruited patients with current gambling problems or pathological gambling according to an NORC DSM-IV screen for gambling problems were randomized to four individual sessions of motivational interviewing (MI), eight sessions of cognitive behavioral group therapy (CBGT), or a no-treatment wait-list control. Gambling-related measures derived from timeline follow-back as well as general levels of anxiety and depression were administered at baseline, termination, and 6 and 12 months posttermination. Treatment showed superiority in some areas over the no-treatment control in the short term, including the primary outcome measure. No differences were found between MI and CBGT at any point in time. Instead, both MI and CBGT produced significant within-group decreases on most outcome measures up to the 12-month follow-up. Both forms of intervention are promising treatments, but there is room for improvement in terms of both outcome and compliance. PMID:19967577

Online Peer-to-Peer Support for Young People With Mental Health Problems: A Systematic Review.

PubMed

Ali, Kathina; Farrer, Louise; Gulliver, Amelia; Griffiths, Kathleen M

2015-01-01

Adolescence and early adulthood are critical periods for the development of mental disorders. Online peer-to-peer communication is popular among young people and may improve mental health by providing social support. Previous systematic reviews have targeted Internet support groups for adults with mental health problems, including depression. However, there have been no systematic reviews examining the effectiveness of online peer-to-peer support in improving the mental health of adolescents and young adults. The aim of this review was to systematically identify available evidence for the effectiveness of online peer-to peer support for young people with mental health problems. The PubMed, PsycInfo, and Cochrane databases were searched using keywords and Medical Subject Headings (MeSH) terms. Retrieved abstracts (n=3934) were double screened and coded. Studies were included if they (1) investigated an online peer-to-peer interaction, (2) the interaction discussed topics related to mental health, (3) the age range of the sample was between 12 to 25 years, and (4) the study evaluated the effectiveness of the peer-to-peer interaction. Six studies satisfied the inclusion criteria for the current review. The studies targeted a range of mental health problems including depression and anxiety (n=2), general psychological problems (n=1), eating disorders (n=1), and substance use (tobacco) (n=2). The majority of studies investigated Internet support groups (n=4), and the remaining studies focused on virtual reality chat sessions (n=2). In almost all studies (n=5), the peer support intervention was moderated by health professionals, researchers or consumers. Studies employed a range of study designs including randomized controlled trials (n=3), pre-post studies (n=2) and one randomized trial. Overall, two of the randomized controlled trials were associated with a significant positive outcome in comparison to the control group at post-intervention. In the remaining four studies, peer-to-peer support was not found to be effective. This systematic review identified an overall lack of high-quality studies examining online peer-to-peer support for young people. Given that peer support is frequently used as an adjunct to Internet interventions for a variety of mental health conditions, there is an urgent need to determine the effectiveness of peer support alone as an active intervention.

Optimal control problem for linear fractional-order systems, described by equations with Hadamard-type derivative

NASA Astrophysics Data System (ADS)

Postnov, Sergey

2017-11-01

Two kinds of optimal control problem are investigated for linear time-invariant fractional-order systems with lumped parameters which dynamics described by equations with Hadamard-type derivative: the problem of control with minimal norm and the problem of control with minimal time at given restriction on control norm. The problem setting with nonlocal initial conditions studied. Admissible controls allowed to be the p-integrable functions (p > 1) at half-interval. The optimal control problem studied by moment method. The correctness and solvability conditions for the corresponding moment problem are derived. For several special cases the optimal control problems stated are solved analytically. Some analogies pointed for results obtained with the results which are known for integer-order systems and fractional-order systems describing by equations with Caputo- and Riemann-Liouville-type derivatives.

The importance of family factors to protect against substance use related problems among Mexican heritage and White youth.

PubMed

Kopak, Albert M; Chen, Angela Chia-Chen; Haas, Steven A; Gillmore, Mary Rogers

2012-07-01

This study examined the ability of family cohesion, parental control, and parent-child attachment to prevent adolescents with a history of drug or alcohol use from experiencing subsequent problems related to their use. Data came from Wave I and Wave II of the National Longitudinal Study of Adolescent Health and included Mexican heritage and White adolescents who reported alcohol use (n = 4894, 25% prevalence) or any other drug use (n = 2875, 14% prevalence) in their lifetime. Logistic regression results indicate greater parent-child attachment predicted lower risk of experiencing drug use problems (OR = 0.87, 95% CI = 0.77-0.98) while stronger family cohesion predicted lower odds of experiencing drug- (OR = 0.82, 95% CI = 0.70-0.97) or alcohol-related (OR = 0.74, 95% CI = 0.65-0.84) problems. Parental control was also negatively associated with odds of problems related to drug use (OR = 0.93, 95% CI = 0.86-0.99) or alcohol use (OR = 0.94, 95% CI = 0.90-0.99). Results also indicated family cohesion was the only protective factor for Mexican heritage youth while family cohesion and parent-child attachment were protective among White youth. Parental control protected White female adolescents from drug use problems more than males. Mexican heritage male adolescents experienced more protection from drug problems compared to females. Findings highlight the need for prevention interventions to emphasize parent-child attachment for White youth and family cohesion for both Mexican-heritage and White youth to decrease adolescent substance users' drug- and alcohol-related problems. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The Importance of Family Factors to Protect Against Substance Use Related Problems among Mexican Heritage and White Youth*

PubMed Central

Kopak, Albert M.; Chen, Angela Chia-Chen; Haas, Steven A.; Gillmore, Mary Rogers

2012-01-01

INTRODUCTION This study examined the ability of family cohesion, parental control, and parent-child attachment to prevent adolescents with a history of drug or alcohol use from experiencing subsequent problems related to their use. METHODS Data came from Wave I and Wave II of the National Longitudinal Study of Adolescent Health and included Mexican heritage and White adolescents who reported alcohol use (n = 4,894, 25% prevalence) or any other drug use (n = 2,875, 14% prevalence) in their lifetime. RESULTS Logistic regression results indicate greater parent-child attachment predicted lower risk of experiencing drug use problems (OR = 0.87, 95% CI = 0.77 – 0.98) while stronger family cohesion predicted lower odds of experiencing drug- (OR = 0.82, 95% CI = 0.70 – 0.97) or alcohol-related (OR = 0.74, 95% CI = 0.65 – 0.84) problems. Parental control was also negatively associated with odds of problems related to drug use (OR = 0.93, 95% CI = 0.86 – 0.99) or alcohol use (OR = 0.94, 95% CI = 0.90 – 0.99). Results also indicated family cohesion was the only protective factor for Mexican heritage youth while family cohesion and parent-child attachment were protective among White youth. Parental control protected White female adolescents from drug use problems more than males. Mexican heritage male adolescents experienced more protection from drug problems compared to females. CONCLUSION Findings highlight the need for prevention interventions to emphasize parent-child attachment for White youth and family cohesion for both Mexican-heritage and White youth to decrease adolescent substance users’ drug- and alcohol-related problems. PMID:22222253

Strategies for Suicide Intervention by Telephone.

ERIC Educational Resources Information Center

Hinson, Jennifer

1982-01-01

Describes techniques helpful for telephone counselors dealing with suicide intervention, including reinstating control, reducing anxiety through problem clarification, and providing hope by active listening and tolerance of dispositions. The use of time-outs and detective work is also discussed. (JAC)

Insights into Pupils' Responses to Practical Investigations from the APU.

ERIC Educational Resources Information Center

Murphy, Patricia

1988-01-01

Describes the Assessment of Performance Unit (APU) Science project. Discusses the findings including perceptions of problems, procedural understanding, control of variables, and measurement strategies. Suggests a change from traditional learning strategies to more student-centered ones. (YP)

Where Do We Go from Here?

ERIC Educational Resources Information Center

MacLeish, William H.

1990-01-01

Explores environmental problem management alternatives cited as demonstrating the human potential for renewal and change. These alternatives include (1) management of wolf/rancher confrontations; (2) energy conservation; (3) agribusiness products and practices; (4) solar technology; and (5) air pollution control. (MCO)

Joint Occurrence of Pain and Sleep Disturbances in People with Dementia. A Systematic Review.

PubMed

Flo, Elisabeth; Bjorvatn, Bjorn; Corbett, Anne; Pallesen, Stale; Husebo, Bettina S

2017-01-01

Advancing age is associated with high prevalence of pain, sleep problems and dementia. Dementia is frequently accompanied by distressing behavioral and psychological symptoms, including sleep problems. The etiology of sleep problems in dementia is multifactorial. It has been suggested that untreated pain may contribute to sleep problems, and pain treatment has been shown to reduce sleep problems in people with dementia. This systematic review aims to provide an overview of the studies that have investigated the association and/or possible interaction between pain and sleep in dementia. A systematic search was performed in MEDLINE, EMBASE, Cochrane and PsychINFO, including text words and MESH terms covering dementia, pain and sleep. Also, reference lists in the included publications were examined to retrieve publications. Publications had to investigate sleep and pain in relation to dementia to be included in this review. The search produced 1750 independent hits. Out of the 49 publications studied in full text, 11 publications were included. Only one controlled trial was identified and represented the only insights to the possible interactional relationship between pain, sleep and dementia. Pain or pain intensity were related to sleep in 6 of the included studies, while the remaining studies could neither support nor contradict a relationship between sleep and pain in people with dementia. None of the studies employed objective sleep assessment. There is a need for high quality studies investigating the interaction between sleep and pain in people with dementia, using objective sleep measurements and pain assessment suitable for people with dementia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The dynamics and control of large flexible space structures, 6

NASA Technical Reports Server (NTRS)

Bainum, P. M.

1983-01-01

The controls analysis based on a truncated finite element model of the 122m. Hoop/Column Antenna System focuses on an analysis of the controllability as well as the synthesis of control laws. Graph theoretic techniques are employed to consider controllability for different combinations of number and locations of actuators. Control law synthesis is based on an application of the linear regulator theory as well as pole placement techniques. Placement of an actuator on the hoop can result in a noticeable improvement in the transient characteristics. The problem of orientation and shape control of an orbiting flexible beam, previously examined, is now extended to include the influence of solar radiation environmental forces. For extremely flexible thin structures modification of control laws may be required and techniques for accomplishing this are explained. Effects of environmental torques are also included in previously developed models of orbiting flexible thin platforms.

Closed-form solutions for linear regulator design of mechanical systems including optimal weighting matrix selection

NASA Technical Reports Server (NTRS)

Hanks, Brantley R.; Skelton, Robert E.

1991-01-01

Vibration in modern structural and mechanical systems can be reduced in amplitude by increasing stiffness, redistributing stiffness and mass, and/or adding damping if design techniques are available to do so. Linear Quadratic Regulator (LQR) theory in modern multivariable control design, attacks the general dissipative elastic system design problem in a global formulation. The optimal design, however, allows electronic connections and phase relations which are not physically practical or possible in passive structural-mechanical devices. The restriction of LQR solutions (to the Algebraic Riccati Equation) to design spaces which can be implemented as passive structural members and/or dampers is addressed. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical system. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist.

Aircraft Loss of Control: Problem Analysis for the Development and Validation of Technology Solutions

NASA Technical Reports Server (NTRS)

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.

Enhancing chemistry problem-solving achievement using problem categorization

NASA Astrophysics Data System (ADS)

Bunce, Diane M.; Gabel, Dorothy L.; Samuel, John V.

The enhancement of chemistry students' skill in problem solving through problem categorization is the focus of this study. Twenty-four students in a freshman chemistry course for health professionals are taught how to solve problems using the explicit method of problem solving (EMPS) (Bunce & Heikkinen, 1986). The EMPS is an organized approach to problem analysis which includes encoding the information given in a problem (Given, Asked For), relating this to what is already in long-term memory (Recall), and planning a solution (Overall Plan) before a mathematical solution is attempted. In addition to the EMPS training, treatment students receive three 40-minute sessions following achievement tests in which they are taught how to categorize problems. Control students use this time to review the EMPS solutions of test questions. Although problem categorization is involved in one section of the EMPS (Recall), treatment students who received specific training in problem categorization demonstrate significantly higher achievement on combination problems (those problems requiring the use of more than one chemical topic for their solution) at (p = 0.01) than their counterparts. Significantly higher achievement for treatment students is also measured on an unannounced test (p = 0.02). Analysis of interview transcripts of both treatment and control students illustrates a Rolodex approach to problem solving employed by all students in this study. The Rolodex approach involves organizing equations used to solve problems on mental index cards and flipping through them, matching units given when a new problem is to be solved. A second phenomenon observed during student interviews is the absence of a link in the conceptual understanding of the chemical concepts involved in a problem and the problem-solving skills employed to correctly solve problems. This study shows that explicit training in categorization skills and the EMPS can lead to higher achievement in complex problem-solving situations (combination problems and unannounced test). However, such achievement may be limited by the lack of linkages between students' conceptual understanding and improved problem-solving skill.

Does understanding relational terminology mediate effects of intervention on compare word problems?

PubMed

Schumacher, Robin F; Fuchs, Lynn S

2012-04-01

The purpose of this study was to assess whether understanding relational terminology (i.e., more, less, and fewer) mediates the effects of intervention on compare word problems. Second-grade classrooms (N=31) were randomly assigned to one of three conditions: researcher-designed word-problem intervention, researcher-designed calculation intervention, or business-as-usual (teacher-designed) control. Students in word-problem intervention classrooms received instruction on the compare problem type, which included a focus on understanding relational terminology within compare word problems. Analyses, which accounted for variance associated with classroom clustering, indicated that (a) compared with the calculation intervention and business-as-usual conditions, word-problem intervention significantly increased performance on all three subtypes of compare problems and on understanding relational terminology, and (b) the intervention effect was fully mediated by students' understanding of relational terminology for one subtype of compare problems and partially mediated by students' understanding of relational terminology for the other two subtypes. Copyright © 2011 Elsevier Inc. All rights reserved.

Effectiveness of a Self Help Cognitive Behavioural Treatment Program for Problem Gamblers: A Randomised Controlled Trial.

PubMed

Oei, T P S; Raylu, N; Lai, W W

2018-06-01

The study aimed to strengthen the scarce literature on self-help treatments for Problem Gambling (PG) by comparing the effectiveness of a Self-Help Cognitive Behavioral Treatment (SHCBT) program (n = 23) with a 6-week Waitlist condition (n = 32) in problem gamblers. Participants were community volunteers with gambling problems and were randomly allocated to the Waitlist and treatment conditions. Results showed significant improvements at post-treatment in gambling behaviors including frequency of gambling, average amount gambled per day and PG symptoms as well as a number of gambling correlates including psychological states (e.g., depression, anxiety and stress), gambling cognitions, gambling urges, gambling related self-efficacy, satisfaction with life, and quality of life among those who completed the SHCBT program, when compared with the waitlist condition. The effect size (partial η 2 ) ranged from .25 to .57 for all assessed outcomes that showed significant improvement from pre- to post-treatment. It was concluded that a self-help CBT program can be beneficial for treating community problem gamblers.

Control problem for a system of linear loaded differential equations

NASA Astrophysics Data System (ADS)

Barseghyan, V. R.; Barseghyan, T. V.

2018-04-01

The problem of control and optimal control for a system of linear loaded differential equations is considered. Necessary and sufficient conditions for complete controllability and conditions for the existence of a program control and the corresponding motion are formulated. The explicit form of control action for the control problem is constructed and a method for solving the problem of optimal control is proposed.

Discrimination and externalizing problems among Moroccan- and Romanian-origin early adolescents in Italy: Moderating role of cultural orientations and impulse control.

PubMed

Miconi, Diana; Altoè, Gianmarco; Salcuni, Silvia; Di Riso, Daniela; Schiff, Sami; Moscardino, Ughetta

2018-05-24

Although discrimination is a common stressor in the everyday life of immigrant youth, individuals are not equally susceptible to its adverse effects. This cross-sectional study aimed to examine whether cultural orientation preferences and impulse control (IC) moderate the association between perceived discrimination and externalizing problems among Moroccan- and Romanian-origin early adolescents in Italy. The sample included 126 Moroccan and 126 Romanian youths (46% girls, 42% first-generation) aged 11-13 years and their parents. Perceived discrimination and cultural orientations were assessed using self-report questionnaires, while IC was evaluated via a computerized version of the Iowa Gambling Task. Externalizing behaviors were assessed via parental report. Cluster analysis identified separated, assimilated, and integrated early adolescents. Regression analyses revealed that when facing discrimination, youths who endorsed separation and exhibited low levels of IC were more vulnerable to externalizing problems. In contrast, among assimilated adolescents the discrimination-externalizing difficulties link was significant at high levels of IC. Furthermore, low levels of IC were associated with more externalizing problems for Romanian, but not for Moroccan early adolescents. Findings underscore the need to consider both cultural orientation processes and early adolescents' ability to control their impulses when developing interventions aimed to reduce discrimination-related problem behaviors in immigrant youth. Implications for theory and practice are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Guaranteed cost control with poles assignment for a flexible air-breathing hypersonic vehicle

NASA Astrophysics Data System (ADS)

Li, Hongyi; Si, Yulin; Wu, Ligang; Hu, Xiaoxiang; Gao, Huijun

2011-05-01

This article investigates the problem of guaranteed cost control for a flexible air-breathing hypersonic vehicle (FAHV). The FAHV includes intricate coupling between the engine and flight dynamics as well as complex interplay between flexible and rigid modes, which results in an intractable system for the control design. A longitudinal model is adopted for control design due to the complexity of the vehicle. First, for a highly nonlinear and coupled FAHV, a linearised model is established around the trim condition, which includes the state of altitude, velocity, angle of attack, pitch angle and pitch rate, etc. Secondly, by using the Lyapunov approach, performance analysis is carried out for the resulting closed-loop FAHV system, whose criterion with respect to guaranteed performance cost and poles assignment is expressed in the framework of linear matrix inequalities (LMIs). The established criterion exhibits a kind of decoupling between the Lyapunov positive-definite matrices to be determined and the FAHV system matrices, which is enabled by the introduction of additional slack matrix variables. Thirdly, a convex optimisation problem with LMI constraints is formulated for designing an admissible controller, which guarantees a prescribed performance cost with the simultaneous consideration of poles assignment for the resulting closed-loop system. Finally, some simulation results are provided to show that the guaranteed cost controller could assign the poles into the desired regional and achieve excellent reference altitude and velocity tracking performance.

Planning and problem-solving training for patients with schizophrenia: a randomized controlled trial

PubMed Central

2011-01-01

Background The purpose of this study was to assess whether planning and problem-solving training is more effective in improving functional capacity in patients with schizophrenia than a training program addressing basic cognitive functions. Methods Eighty-nine patients with schizophrenia were randomly assigned either to a computer assisted training of planning and problem-solving or a training of basic cognition. Outcome variables included planning and problem-solving ability as well as functional capacity, which represents a proxy measure for functional outcome. Results Planning and problem-solving training improved one measure of planning and problem-solving more strongly than basic cognition training, while two other measures of planning did not show a differential effect. Participants in both groups improved over time in functional capacity. There was no differential effect of the interventions on functional capacity. Conclusion A differential effect of targeting specific cognitive functions on functional capacity could not be established. Small differences on cognitive outcome variables indicate a potential for differential effects. This will have to be addressed in further research including longer treatment programs and other settings. Trial registration ClinicalTrials.gov NCT00507988 PMID:21527028

Establishment and evaluation of a theater influenza monitoring platform.

PubMed

Wang, Jian; Yang, Hui-Suo; Deng, Bing; Shi, Meng-Jing; Li, Xiang-Da; Nian, Qing-Gong; Song, Wen-Jing; Bing, Feng; Li, Qing-Feng

2017-11-20

Influenza is an acute respiratory infectious disease with a high incidence rate in the Chinese army, which directly disturbs military training and affects soldiers' health. Influenza surveillance systems are widely used around the world and play an important role in influenza epidemic prevention and control. As a theater centers for disease prevention and control, we established an influenza monitoring platform (IMP) in 2014 to strengthen the monitoring of influenza-like illness and influenza virus infection. In this study, we introduced the constitution, influenza virus detection, and quality control for an IMP. The monitoring effect was also evaluated by comparing the monitoring data with data from national influenza surveillance systems. The experiences and problems associated with the platform also were summarized. A theater IMP was established based on 3 levels of medical units, including monitoring sites, testing laboratories and a checking laboratory. A series of measures were taken to guarantee the quality of monitoring, such as technical training, a unified process, sufficient supervision and timely communication. The platform has run smoothly for 3 monitoring years to date. In the 2014-2015 and 2016-2017 monitoring years, sample amount coincided with that obtained from the National Influenza Surveillance program. In the 2015-2016 monitoring year, due to the strict prevention and control measures, an influenza epidemic peak was avoided in monitoring units, and the monitoring data did not coincide with that of the National Influenza Surveillance program. Several problems, including insufficient attention, unreasonable administrative intervention or subordination relationships, and the necessity of detection in monitoring sites were still observed. A theater IMP was established rationally and played a deserved role in the prevention and control of influenza. However, several problems remain to be solved.

Using ‘appreciative inquiry’ in India to improve infection control practices in maternity care: a qualitative study

PubMed Central

Sharma, Bharati; Ramani, K.V.; Mavalankar, Dileep; Kanguru, Lovney; Hussein, Julia

2015-01-01

Background Infections acquired during childbirth are a common cause of maternal and perinatal mortality and morbidity. Changing provider behaviour and organisational settings within the health system is key to reducing the spread of infection. Objective To explore the opinions of health personnel on health system factors related to infection control and their perceptions of change in a sample of hospital maternity units. Design An organisational change process called ‘appreciative inquiry’ (AI) was introduced in three maternity units of hospitals in Gujarat, India. AI is a change process that builds on recognition of positive actions, behaviours, and attitudes. In-depth interviews were conducted with health personnel to elicit information on the environment within which they work, including physical and organisational factors, motivation, awareness, practices, perceptions of their role, and other health system factors related to infection control activities. Data were obtained from three hospitals which implemented AI and another three not involved in the intervention. Results Challenges which emerged included management processes (e.g. decision-making and problem-solving modalities), human resource shortages, and physical infrastructure (e.g. space, water, and electricity supplies). AI was perceived as having a positive influence on infection control practices. Respondents also said that management processes improved although some hospitals had already undergone an accreditation process which could have influenced the changes described. Participants reported that team relationships had been strengthened due to AI. Conclusion Technical knowledge is often emphasised in health care settings and less attention is paid to factors such as team relationships, leadership, and problem solving. AI can contribute to improving infection control by catalysing and creating forums for team building, shared decision making and problem solving in an enabling environment. PMID:26119249

Using 'appreciative inquiry' in India to improve infection control practices in maternity care: a qualitative study.

PubMed

Sharma, Bharati; Ramani, K V; Mavalankar, Dileep; Kanguru, Lovney; Hussein, Julia

2015-01-01

Infections acquired during childbirth are a common cause of maternal and perinatal mortality and morbidity. Changing provider behaviour and organisational settings within the health system is key to reducing the spread of infection. To explore the opinions of health personnel on health system factors related to infection control and their perceptions of change in a sample of hospital maternity units. An organisational change process called 'appreciative inquiry' (AI) was introduced in three maternity units of hospitals in Gujarat, India. AI is a change process that builds on recognition of positive actions, behaviours, and attitudes. In-depth interviews were conducted with health personnel to elicit information on the environment within which they work, including physical and organisational factors, motivation, awareness, practices, perceptions of their role, and other health system factors related to infection control activities. Data were obtained from three hospitals which implemented AI and another three not involved in the intervention. Challenges which emerged included management processes (e.g. decision-making and problem-solving modalities), human resource shortages, and physical infrastructure (e.g. space, water, and electricity supplies). AI was perceived as having a positive influence on infection control practices. Respondents also said that management processes improved although some hospitals had already undergone an accreditation process which could have influenced the changes described. Participants reported that team relationships had been strengthened due to AI. Technical knowledge is often emphasised in health care settings and less attention is paid to factors such as team relationships, leadership, and problem solving. AI can contribute to improving infection control by catalysing and creating forums for team building, shared decision making and problem solving in an enabling environment.

Unmanned surface traverses of Mars and Moon: Science objectives, payloads, operations

NASA Technical Reports Server (NTRS)

Jaffe, L. D.; Choate, R.

1973-01-01

Science objectives and properties to be measured are outlined for long surface traverse missions on Mars and the Moon, with remotely-controlled roving vehicles. A series of candidate rover payloads is proposed for each planet, varying in weight, cost, purpose, and development needed. The smallest weighs 35 kg; the largest almost 300 kg. A high degree of internal control will be needed on the Mars rover, including the ability to carry out complex science sequences. Decision-making by humans in the Mars mission includes supervisory control of rover operations and selection of features and samples of geological and biological interest. For the lunar mission, less control on the rover and more on earth is appropriate. Science portions of the rover mission profile are outlined, with timelines and mileage breakdowns. Operational problem areas for Mars include control, communications, data storage, night operations, and the mission operations system. For the moon, science data storage on the rover would be unnecessary and control much simpler.

Fixed-Order Mixed Norm Designs for Building Vibration Control

NASA Technical Reports Server (NTRS)

Whorton, Mark S.; Calise, Anthony J.

2000-01-01

This study investigates the use of H2, mu-synthesis, and mixed H2/mu methods to construct full order controllers and optimized controllers of fixed dimensions. The benchmark problem definition is first extended to include uncertainty within the controller bandwidth in the form of parametric uncertainty representative of uncertainty in the natural frequencies of the design model. The sensitivity of H2 design to unmodeled dynamics and parametric uncertainty is evaluated for a range of controller levels of authority. Next, mu-synthesis methods are applied to design full order compensators that are robust to both unmodeled dynamics and to parametric uncertainty. Finally, a set of mixed H2/mu compensators are designed which are optimized for a fixed compensator dimension. These mixed norm designs recover the H2 design performance levels while providing the same levels of robust stability as the mu designs. It is shown that designing with the mixed norm approach permits higher levels of controller authority for which the H2 designs are destabilizing. The benchmark problem is that of an active tendon system. The controller designs are all based on the use of acceleration feedback.

Some wake-related operational limitations of rotorcraft

NASA Technical Reports Server (NTRS)

Heyson, H. H.

1980-01-01

Wind tunnel measurements show that the wake of a rotor, except at near hovering speeds, is not like that of a propeller. The wake is more like that of a wing except that, because of the slow speeds, the wake velocities may be much greater. The helicopter can produce a wake hazard to following light aircraft that is disproportionately great compared to an equivalent fixed wing aircraft. This hazard should be recognized by both pilots and airport controllers when operating in congested areas. Ground effect is generally counted as a blessing since it allows overloaded takeoffs; however, it also introduces additional operation problems. These problems include premature blade stall in hover, settling in forward transition, shuddering in approach to touchdown and complicatons with yaw control. Some of these problems were treated analytically in an approximate manner and reasonable experiment agreement was obtained. An awareness of these effects can prepare the user for their appearance and their consequences.

AMFESYS: Modelling and diagnosis functions for operations support

NASA Technical Reports Server (NTRS)

Wheadon, J.

1993-01-01

Packetized telemetry, combined with low station coverage for close-earth satellites, may introduce new problems in presenting to the operator a clear picture of what the spacecraft is doing. A recent ESOC study has gone some way to show, by means of a practical demonstration, how the use of subsystem models combined with artificial intelligence techniques, within a real-time spacecraft control system (SCS), can help to overcome these problems. A spin-off from using these techniques can be an improvement in the reliability of the telemetry (TM) limit-checking function, as well as the telecommand verification function, of the Spacecraft Control systems (SCS). The problem and how it was addressed, including an overview of the 'AMF Expert System' prototype are described, and proposes further work which needs to be done to prove the concept. The Automatic Mirror Furnace is part of the payload of the European Retrievable Carrier (EURECA) spacecraft, which was launched in July 1992.