Science.gov

Sample records for affect control theory

  1. An Affect Control Theory of Technology

    ERIC Educational Resources Information Center

    Shank, Daniel B.

    2010-01-01

    Affect control theory is a theory of interaction that takes into account cultural meanings. Affect control research has previously considered interaction with technology, but there remains a lack of theorizing about inclusion of technology within the theory. This paper lays a foundation for an affect control theory of technology by addressing key…

  2. Predicting performance expectations from affective impressions: linking affect control theory and status characteristics theory.

    PubMed

    Dippong, Joseph; Kalkhoff, Will

    2015-03-01

    Affect control theory (ACT) and status characteristics theory (SCT) offer separate and distinct explanations for how individuals interpret and process status- and power-relevant information about interaction partners. Existing research within affect control theory offers evidence that status and power are related to the affective impressions that individuals form of others along the dimensions of evaluation and potency, respectively. Alternately, status characteristics theory suggests that status and power influence interaction through the mediating cognitive construct of performance expectations. Although both theories have amassed an impressive amount of empirical support, research has yet to articulate theoretical and empirical connections between affective impressions and performance expectations. The purpose of our study is to address this gap. Elaborating a link between ACT and SCT in terms of their central concepts can serve as a stepping stone to improving the explanatory capacity of both theories, while providing a potential bridge by which they can be employed jointly.

  3. Affective Dynamics of Leadership: An Experimental Test of Affect Control Theory

    ERIC Educational Resources Information Center

    Schroder, Tobias; Scholl, Wolfgang

    2009-01-01

    Affect Control Theory (ACT; Heise 1979, 2007) states that people control social interactions by striving to maintain culturally shared feelings about the situation. The theory is based on mathematical models of language-based impression formation. In a laboratory experiment, we tested the predictive power of a new German-language ACT model with…

  4. Comment: Affect Control Theory and Cultural Priming: A Perspective from Cultural Neuroscience.

    PubMed

    Pornpattananangkul, Narun; Chiao, Joan Y

    2014-04-01

    Affect control theory posits that emotions are constructed by social and cultural forces. Rogers, Schröder, and von Scheve (2014) introduce affect control theory as a conceptual and methodological "hub," linking theories from different disciplines across levels of analysis. To illustrate this further, we apply their framework to cultural priming, an experimental technique in cultural psychology and neuroscience for testing how exposure to cultural symbols (e.g., words and pictures) changes people's behavior, cognition, and emotion. Our analysis supports the use of affect control theory in linking different levels of analysis while leaving some opening questions for improving such a framework in future research.

  5. Auditory top-down control and affective theory of mind in schizophrenia with and without hallucinations.

    PubMed

    Rominger, Christian; Bleier, Angelika; Fitz, Werner; Marksteiner, Josef; Fink, Andreas; Papousek, Ilona; Weiss, Elisabeth M

    2016-07-01

    Social cognitive impairments may represent a core feature of schizophrenia and above all are a strong predictor of positive psychotic symptoms. Previous studies could show that reduced inhibitory top-down control contributes to deficits in theory of mind abilities and is involved in the genesis of hallucinations. The current study aimed to investigate the relationship between auditory inhibition, affective theory of mind and the experience of hallucinations in patients with schizophrenia. In the present study, 20 in-patients with schizophrenia and 20 healthy controls completed a social cognition task (the Reading the Mind in the Eyes Test) and an inhibitory top-down Dichotic Listening Test. Schizophrenia patients with greater severity of hallucinations showed impaired affective theory of mind as well as impaired inhibitory top-down control. More dysfunctional top-down inhibition was associated with poorer affective theory of mind performance, and seemed to mediate the association between impairment to affective theory of mind and severity of hallucinations. The findings support the idea of impaired theory of mind as a trait marker of schizophrenia. In addition, dysfunctional top-down inhibition may give rise to hallucinations and may further impair affective theory of mind skills in schizophrenia.

  6. The Dynamic Nature of Leisure Experience: An Application of Affect Control Theory.

    ERIC Educational Resources Information Center

    Lee, BongKoo; Shafer, C. Scott

    2002-01-01

    Applied Affect Control Theory (ACT) to investigate the interaction process between leisure participants and their environment. Surveys of people on an urban, multiple-use trail indicated that most exhibited a dynamic emotional experience even though they were in the setting a short time. Respondents exhibited different emotions across events.…

  7. Redefining a Bizarre Situation: Relative Concept Stability in Affect Control Theory

    ERIC Educational Resources Information Center

    Nelson, Steven M.

    2006-01-01

    I analyze the process by which we react cognitively to information that contradicts our culturally held sentiments in the context of affect control theory. When bizarre, unanticipated events come to our attention and we have no opportunity to act so as to alter them, we must reidentify at least one event component: the actor, the behavior, or the…

  8. A Multimodal Theory of Affect Diffusion.

    PubMed

    Peters, Kim; Kashima, Yoshihisa

    2015-09-01

    There is broad consensus in the literature that affect diffuses through social networks (such that a person may "acquire" or "catch" an affective state from his or her social contacts). It is further assumed that affect diffusion primarily occurs as the result of people's tendencies to synchronize their affective actions (such as smiles and frowns). However, as we show, there is a lack of clarity in the literature about the substrate and scope of affect diffusion. One consequence of this is a difficulty in distinguishing between affect diffusion and several other affective influence phenomena that look similar but have very different consequences. There is also a growing body of evidence that action synchrony is unlikely to be the only, or indeed the most important, pathway for affect diffusion. This paper has 2 key aims: (a) to craft a formal definition of affect diffusion that does justice to the core of the phenomenon while distinguishing it from other phenomena with which it is frequently confounded and (b) to advance a theory of the mechanisms of affect diffusion. This theory, which we call the multimodal theory of affect diffusion, identifies 3 parallel multimodal mechanisms that may act as routes for affect diffusion. It also provides a basis for novel predictions about the conditions under which affect is most likely to diffuse.

  9. Splines and control theory

    NASA Technical Reports Server (NTRS)

    Zhang, Zhimin; Tomlinson, John; Martin, Clyde

    1994-01-01

    In this work, the relationship between splines and the control theory has been analyzed. We show that spline functions can be constructed naturally from the control theory. By establishing a framework based on control theory, we provide a simple and systematic way to construct splines. We have constructed the traditional spline functions including the polynomial splines and the classical exponential spline. We have also discovered some new spline functions such as trigonometric splines and the combination of polynomial, exponential and trigonometric splines. The method proposed in this paper is easy to implement. Some numerical experiments are performed to investigate properties of different spline approximations.

  10. Conference on Operator Theory, Wavelet Theory and Control Theory

    DTIC Science & Technology

    1993-09-30

    Bourbaki 662 (1985-1986). [9] Meyer, Y., Ondelettes et operateurs I, Hermann editeurs des sciences et des arts, 1990. [10] Natanson, I. P., Theory of...OPERATOR THEORY , WAVELET THEORY & CONTROL THEORY (U)F 6. AUTHOR(S) 2304/ES Professor Xingde Dai F49620-93-1-0180 7. PERFORMING ORGANIZATION NAME(S) AND...1STRIBUTION IS UNLIMITED UTL 13. ABSTRACT (Maximum 200 words) The conference on Interaction Between Operator Theory , Wavelet Theory and Control Theory

  11. Affective cognition: Exploring lay theories of emotion.

    PubMed

    Ong, Desmond C; Zaki, Jamil; Goodman, Noah D

    2015-10-01

    Humans skillfully reason about others' emotions, a phenomenon we term affective cognition. Despite its importance, few formal, quantitative theories have described the mechanisms supporting this phenomenon. We propose that affective cognition involves applying domain-general reasoning processes to domain-specific content knowledge. Observers' knowledge about emotions is represented in rich and coherent lay theories, which comprise consistent relationships between situations, emotions, and behaviors. Observers utilize this knowledge in deciphering social agents' behavior and signals (e.g., facial expressions), in a manner similar to rational inference in other domains. We construct a computational model of a lay theory of emotion, drawing on tools from Bayesian statistics, and test this model across four experiments in which observers drew inferences about others' emotions in a simple gambling paradigm. This work makes two main contributions. First, the model accurately captures observers' flexible but consistent reasoning about the ways that events and others' emotional responses to those events relate to each other. Second, our work models the problem of emotional cue integration-reasoning about others' emotion from multiple emotional cues-as rational inference via Bayes' rule, and we show that this model tightly tracks human observers' empirical judgments. Our results reveal a deep structural relationship between affective cognition and other forms of inference, and suggest wide-ranging applications to basic psychological theory and psychiatry.

  12. CHALLENGES OF MODERN CONTROL THEORY

    DTIC Science & Technology

    The fundamental objective of the new scientific discipline called ’ control theory ’ is that of modifying the behavior of a system subject to various...possible contributions of modern control theory to the biomedical domain are briefly indicated.

  13. Do scientific theories affect men's evaluations of sex crimes?

    PubMed

    Dar-Nimrod, Ilan; Heine, Steven J; Cheung, Benjamin Y; Schaller, Mark

    2011-01-01

    Evolutionary psychology accounts of gender differences in sexual behaviors in general and men's sexual aggression, in particular, has been criticized for legitimizing males' sexual misconduct. To empirically assess such critiques, two studies examined how men's judgments of male sex crimes (solicitation of sex from a prostitute; rape) are influenced by exposure to (a) evolutionary psychological theories and (b) social-constructivist theories. Across two studies, a consistent pattern emerged compared with a control condition (a) exposure to evolutionary psychology theories had no observable impact on male judgments of men's criminal sexual behavior, whereas (b) exposure to social-constructivist theories did affect judgments, leading men to evaluate sex crimes more harshly. Additional results (from Study 2) indicate that this effect is mediated by perceptions of male control over sexual urges. These results have implications for journalists, educators, and scientists. Aggr. Behav. 37:440-449, 2011. © 2011 Wiley-Liss, Inc.

  14. Comparative study of Oswald ripening and trans-interface diffusion-controlled theory models: Coarsening of γ' precipitates affected by elastic strain along a concentration gradient

    NASA Astrophysics Data System (ADS)

    Garay-Reyes, C. G.; Hernández-Martínez, S. E.; Hernández-Rivera, J. L.; Cruz-Rivera, J. J.; Gutiérrez-Castañeda, E. J.; Dorantes-Rosales, H. J.; Aguilar-Santillan, J.; Martínez-Sánchez, R.

    2017-02-01

    According to Lifshitz, Slyozov, and Wagner (LSW) and Trans-Interface Diffusion-Controlled (TICD) theoretical models, this paper reports the microstructure and its coarsening behavior of γ' metastable-coherent precipitates in concentration gradient of Ni-13.75Ti (at%)/Ni generated by diffusion couple. The coarsening of precipitates was evaluated in two different Ti contents (R1-11.4Ti (at%) and R2-13Ti (at%)) generated along the concentration gradient and includes average size, size distributions and growth rate. The solvus and metastable-coherent bimodal lines as determined at 850 °C of 9.16 (at%) and 9.92Ti (at%) respectively by scanning electron microscopy. This paper suggests that elastic strains produced by the matrix/precipitate lattice mismatch caused significant deviations between the experimental results and those predicted by the LSW or TIDC theories. Activation energies for TIDC (Q i ) and LSW (Q r ) are Q r : 219.69 and 172.61 kJ mol-1 for R1 and R2 regions, respectively, and Q i : 218.46 and 164.56 kJmol-1 for R1 and R2 regions, respectively. A concentration gradient allows the study of various alloys with different concentration and volume-fraction in a single sample.

  15. Optimal Periodic Control Theory.

    DTIC Science & Technology

    1980-08-01

    are control variables. For many aircraft, this energy state space produces a hodograph which is not convex. The physical explanation for this is that...convexity in the hodograph and preserve an "optimal" steady-state cruise, Schultz and Zagalsky [61 revised the energy state model so that altitude becomes a

  16. Social Control Theory and Delinquency.

    ERIC Educational Resources Information Center

    Wiatrowski, Michael D.; And Others

    1981-01-01

    Develops and tests multivariate models of social control theory which simultaneously consider how four bonds to society (attachment, commitment, involvement, and belief) operate in relation to delinquency. Suggests a revised formulation of social control, after adding background factors (measures of social class and ability) to the model.…

  17. Comparing Multiple Discrepancies Theory to Affective Models of Subjective Wellbeing

    ERIC Educational Resources Information Center

    Blore, Jed D.; Stokes, Mark A.; Mellor, David; Firth, Lucy; Cummins, Robert A.

    2011-01-01

    The Subjective Wellbeing (SWB) literature is replete with competing theories detailing the mechanisms underlying the construction and maintenance of SWB. The current study aimed to compare and contrast two of these approaches: multiple discrepancies theory (MDT) and an affective-cognitive theory of SWB. MDT posits SWB to be the result of perceived…

  18. Transition delay using control theory.

    PubMed

    Bagheri, S; Henningson, D S

    2011-04-13

    This review gives an account of recent research efforts to use feedback control for the delay of laminar-turbulent transition in wall-bounded shear flows. The emphasis is on reducing the growth of small-amplitude disturbances in the boundary layer using numerical simulations and a linear control approach. Starting with the application of classical control theory to two-dimensional perturbations developing in spatially invariant flows, flow control based on control theory has progressed towards more realistic three-dimensional, spatially inhomogeneous flow configurations with localized sensing/actuation. The development of low-dimensional models of the Navier-Stokes equations has played a key role in this progress. Moreover, shortcomings and future challenges, as well as recent experimental advances in this multi-disciplinary field, are discussed.

  19. Aerodynamic design via control theory

    NASA Technical Reports Server (NTRS)

    Jameson, Antony

    1988-01-01

    The question of how to modify aerodynamic design in order to improve performance is addressed. Representative examples are given to demonstrate the computational feasibility of using control theory for such a purpose. An introduction and historical survey of the subject is included.

  20. How Causal Knowledge Affects Classification: A Generative Theory of Categorization

    ERIC Educational Resources Information Center

    Rehder, Bob; Kim, ShinWoo

    2006-01-01

    Several theories have been proposed regarding how causal relations among features of objects affect how those objects are classified. The assumptions of these theories were tested in 3 experiments that manipulated the causal knowledge associated with novel categories. There were 3 results. The 1st was a multiple cause effect in which a feature's…

  1. Positive Affect and Negative Affect as Modulators of Cognition and Motivation: The Rediscovery of Affect in Achievement Goal Theory

    ERIC Educational Resources Information Center

    Bjornebekk, Gunnar

    2008-01-01

    A central hypothesis of classical motivation theory is that affect underlies motivation and its behavioural manifestations. However, this has been largely ignored in the past 30 years because social cognitivism has been the dominant theory. As a result, studies have concentrated on social cognitive processes when analysing those factors that…

  2. Ongoing neural development of affective theory of mind in adolescence.

    PubMed

    Vetter, Nora C; Weigelt, Sarah; Döhnel, Katrin; Smolka, Michael N; Kliegel, Matthias

    2014-07-01

    Affective Theory of Mind (ToM), an important aspect of ToM, involves the understanding of affective mental states. This ability is critical in the developmental phase of adolescence, which is often related with socio-emotional problems. Using a developmentally sensitive behavioral task in combination with functional magnetic resonance imaging, the present study investigated the neural development of affective ToM throughout adolescence. Eighteen adolescent (ages 12-14 years) and 18 young adult women (aged 19-25 years) were scanned while evaluating complex affective mental states depicted by actors in video clips. The ventromedial prefrontal cortex (vmPFC) showed significantly stronger activation in adolescents in comparison to adults in the affective ToM condition. Current results indicate that the vmPFC might be involved in the development of affective ToM processing in adolescence.

  3. Implications of Affective and Social Neuroscience for Educational Theory

    ERIC Educational Resources Information Center

    Immordino-Yang, Mary Helen

    2011-01-01

    The past decade has seen major advances in cognitive, affective and social neuroscience that have the potential to revolutionize educational theories about learning. The importance of emotion and social learning has long been recognized in education, but due to technological limitations in neuroscience research techniques, treatment of these…

  4. AN APPLICATION OF OPTIMAL CONTROL THEORY.

    DTIC Science & Technology

    The purpose of this article is to show that optimal control theory can be used to develop a control strategy for a practical system, namely a distillation column. The approach will be to model the complex system with a simple model, use optimal control theory to determine a control strategy for the simple model, and then apply the results to the original system. (Author)

  5. AN INTRODUCTION TO OPTIMAL CONTROL THEORY.

    DTIC Science & Technology

    The report presents an introduction to some of the concepts and results currently popular in optimal control theory . The introduction is intended...for someone acquainted with ordinary differential equations and real variables, but with no prior knowledge of control theory . The material covered

  6. Money Affects Theory of Mind Differently by Gender

    PubMed Central

    Ridinger, Garret; McBride, Michael

    2015-01-01

    Theory of Mind (ToM) ─ the ability to understand other’s thoughts, intentions, and emotions ─ is important for navigating interpersonal relationships, avoiding conflict, and empathizing. Prior research has identified many factors that affect one’s ToM ability, but little work has examined how different kinds of monetary incentives affect ToM ability. We ask: Does money affect ToM ability? If so, how does the effect depend on the structure of monetary incentives? How do the differences depend on gender? We hypothesize that money will affect ToM ability differently by gender: monetary rewards increase males’ motivation to express ToM ability while simultaneously crowding out females’ motivation. This prediction is confirmed in an experiment that varies the structure of monetary rewards for correct answers in the Reading the Mind in the Eyes Test (RMET). RMET scores decrease for females and increase for males with individual payments, and this effect is stronger with competitively-structured payments. RMET scores do not significantly change when monetary earnings go to a charity. Whether money improves or hinders ToM ability, and, hence, success in social interactions, thus depends on the interaction of gender and monetary incentive structure. PMID:26633171

  7. Money Affects Theory of Mind Differently by Gender.

    PubMed

    Ridinger, Garret; McBride, Michael

    2015-01-01

    Theory of Mind (ToM)--the ability to understand other's thoughts, intentions, and emotions--is important for navigating interpersonal relationships, avoiding conflict, and empathizing. Prior research has identified many factors that affect one's ToM ability, but little work has examined how different kinds of monetary incentives affect ToM ability. We ask: Does money affect ToM ability? If so, how does the effect depend on the structure of monetary incentives? How do the differences depend on gender? We hypothesize that money will affect ToM ability differently by gender: monetary rewards increase males' motivation to express ToM ability while simultaneously crowding out females' motivation. This prediction is confirmed in an experiment that varies the structure of monetary rewards for correct answers in the Reading the Mind in the Eyes Test (RMET). RMET scores decrease for females and increase for males with individual payments, and this effect is stronger with competitively-structured payments. RMET scores do not significantly change when monetary earnings go to a charity. Whether money improves or hinders ToM ability, and, hence, success in social interactions, thus depends on the interaction of gender and monetary incentive structure.

  8. Vehicle dynamics applications of optimal control theory

    NASA Astrophysics Data System (ADS)

    Sharp, R. S.; Peng, Huei

    2011-07-01

    The aim of the paper is to survey the various forms of optimal-control theory which have been applied to automotive problems and to present illustrative examples of applications studies, with assessments of the state of the art and of the contributions made through the use of optimal-control ideas. After a short introduction to the topic mentioning several questions to which optimal-control theory has been addressed, brief reviews of automotive-applicable optimal-control theory are given. There are outlines of the Linear Quadratic Regulator, without and with state reconstruction and then with the addition of disturbance preview, the nonlinear regulator or state-dependent-Riccati equation method, general numerical optimal-control theory including indirect and direct methods, model predictive control and robust control. Applications of the theory to active and semi-active suspension design and performance, worst-case manoeuvring, minimum-time manoeuvring and high-quality driving are then discussed in detail. Application sections describe the problem, the theory that has been used, what has been discovered and what remains to be found. The record of optimal-control theory in aiding the understanding of the various issues, in helping with system designs and knowledge of what is possible, and in guiding future research is assessed. Some ideas about future work are included.

  9. Applications of robust control theory - Educational implications

    NASA Technical Reports Server (NTRS)

    Dorato, P.; Yedavalli, R. K.

    1992-01-01

    A survey is made of applications of robust control theory to problems of flight control, control of flexible space structures, and engine control which have appeared in recent conferences and journals. An analysis is made of which theoretical techniques are most commonly used and what implications this has for graduate and undergraduate education in aerospace engineering.

  10. Do scientific theories affect men’s evaluations of sex crimes?

    PubMed Central

    DAR-NIMROD, ILAN; HEINE, STEVEN J.; CHEUNG, BENJAMIN Y.; SCHALLER, MARK

    2012-01-01

    Evolutionary Psychology accounts of gender differences in sexual behaviors in general and men’s sexual aggression in particular, have been criticized for legitimizing males’ sexual misconduct. To empirically assess such critiques, two studies examined how men’s judgments of male sex crimes (solicitation of sex from a prostitute; rape) are influenced by exposure to (a) evolutionary psychological theories, and (b) social-constructivist theories. Across two studies a consistent pattern emerged: compared to a control condition, (a) exposure to evolutionary psychology theories had no observable impact on male judgments of men’s criminal sexual behavior, whereas (b) exposure to social-constructivist theories did affect judgments, leading men to evaluate sex crimes more harshly. Additional results (from Study 2) indicate that this effect is mediated by perceptions of male control over sexual urges. These results have implications, for journalists, educators, and scientists. PMID:21678431

  11. Development of affective theory of mind across adolescence: disentangling the role of executive functions.

    PubMed

    Vetter, Nora C; Altgassen, Mareike; Phillips, Louise; Mahy, Caitlin E V; Kliegel, Matthias

    2013-01-01

    Theory of mind, the ability to understand mental states, involves inferences about others' cognitive (cognitive theory of mind) and emotional (affective theory of mind) mental states. The current study explored the role of executive functions in developing affective theory of mind across adolescence. Affective theory of mind and three subcomponents of executive functions (inhibition, updating, and shifting) were measured. Affective theory of mind was positively related to age, and all three executive functions. Specifically, inhibition explained the largest amount of variance in age-related differences in affective theory of mind.

  12. Control theory and psychopathology: an integrative approach.

    PubMed

    Mansell, Warren

    2005-06-01

    Perceptual control theory (PCT; Powers, 1973) is presented and adapted as a framework to understand the causes, maintenance, and treatment of psychological disorders. PCT provides dynamic, working models based on the principle that goal-directed activity arises from a hierarchy of negative feedback loops that control perception through control of the environment. The theory proposes that psychological distress arises from the unresolved conflict between goals. The present paper integrates PCT, control theory, and self-regulatory approaches to psychopathology and psychotherapy and recent empirical findings, particularly in the field of cognitive therapy. The approach aims to offer fresh insights into the role of goal conflict, automatic processes, imagery, perceptual distortion, and loss of control in psychological disorders. Implications for psychological therapy are discussed, including an integration of the existing work on the assessment of control profiles and the use of assertive versus yielding modes of control.

  13. Advanced Topics in Control Systems Theory

    NASA Astrophysics Data System (ADS)

    Lorsa, Antonio; Lamnabhi-Lagarrigue, Françoise; Panteley, Elena

    Advanced Topics in Control Systems Theory contains selected contributions written by lecturers at the third (annual) Formation d'Automatique de Paris (FAP) (Graduate Control School in Paris). Following on from the lecture notes from the second FAP (Volume 311 in the same series) it is addressed to graduate students and researchers in control theory with topics touching on a variety of areas of interest to the control community such as nonlinear optimal control, observer design, stability analysis and structural properties of linear systems.

  14. Quantitative Robust Control Engineering: Theory and Applications

    DTIC Science & Technology

    2006-09-01

    1992). Discrete quantitative feedback technique, Capítulo 16 en el libro : Digital Control Systems: theory, hardware, software, 2ª edicion. McGraw...Rasmussen S.J., Garcia-Sanz, M. (2001, 2005), Software de diseño del libro Quantitative Feedback Theory: Fundamentals and Applications. Edición 2ª. CRCPress

  15. Control theory meets synthetic biology.

    PubMed

    Del Vecchio, Domitilla; Dy, Aaron J; Qian, Yili

    2016-07-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology.

  16. Control theory meets synthetic biology

    PubMed Central

    2016-01-01

    The past several years have witnessed an increased presence of control theoretic concepts in synthetic biology. This review presents an organized summary of how these control design concepts have been applied to tackle a variety of problems faced when building synthetic biomolecular circuits in living cells. In particular, we describe success stories that demonstrate how simple or more elaborate control design methods can be used to make the behaviour of synthetic genetic circuits within a single cell or across a cell population more reliable, predictable and robust to perturbations. The description especially highlights technical challenges that uniquely arise from the need to implement control designs within a new hardware setting, along with implemented or proposed solutions. Some engineering solutions employing complex feedback control schemes are also described, which, however, still require a deeper theoretical analysis of stability, performance and robustness properties. Overall, this paper should help synthetic biologists become familiar with feedback control concepts as they can be used in their application area. At the same time, it should provide some domain knowledge to control theorists who wish to enter the rising and exciting field of synthetic biology. PMID:27440256

  17. An information theory account of cognitive control

    PubMed Central

    Fan, Jin

    2014-01-01

    Our ability to efficiently process information and generate appropriate responses depends on the processes collectively called cognitive control. Despite a considerable focus in the literature on the cognitive control of information processing, neural mechanisms underlying control are still unclear, and have not been characterized by considering the quantity of information to be processed. A novel and comprehensive account of cognitive control is proposed using concepts from information theory, which is concerned with communication system analysis and the quantification of information. This account treats the brain as an information-processing entity where cognitive control and its underlying brain networks play a pivotal role in dealing with conditions of uncertainty. This hypothesis and theory article justifies the validity and properties of such an account and relates experimental findings to the frontoparietal network under the framework of information theory. PMID:25228875

  18. An information theory account of cognitive control.

    PubMed

    Fan, Jin

    2014-01-01

    Our ability to efficiently process information and generate appropriate responses depends on the processes collectively called cognitive control. Despite a considerable focus in the literature on the cognitive control of information processing, neural mechanisms underlying control are still unclear, and have not been characterized by considering the quantity of information to be processed. A novel and comprehensive account of cognitive control is proposed using concepts from information theory, which is concerned with communication system analysis and the quantification of information. This account treats the brain as an information-processing entity where cognitive control and its underlying brain networks play a pivotal role in dealing with conditions of uncertainty. This hypothesis and theory article justifies the validity and properties of such an account and relates experimental findings to the frontoparietal network under the framework of information theory.

  19. Elevated emotional reactivity in affective but not cognitive components of theory of mind: a psychophysiological study.

    PubMed

    Kalbe, E; Grabenhorst, F; Brand, M; Kessler, J; Hilker, R; Markowitsch, H J

    2007-03-01

    Recent research proposes that theory of mind (ToM), that is the ability to infer other people's mental state, is a multidimensional construct and that a distinction may be made between affective and cognitive ToM. We examined whether these two subcomponents of ToM correspond to different levels in skin conductance responses (SCRs). Seventeen healthy adults listened to ten affective (faux pas) ToM stories, ten cognitive ToM stories and ten non-ToM stories. Results demonstrated significantly elevated SCR for affective ToM as compared with cognitive ToM and control stories, with no differences in SCR levels in the latter two story types. We discuss the possible underlying mechanisms for these differential psychophysiological correlates of affective and cognitive ToM processing, and suggest further investigations especially in clinical populations.

  20. Positive affect increases secondary control among causally uncertain individuals.

    PubMed

    Tobin, Stephanie J; George, Melanie P

    2015-01-01

    Secondary control (acceptance of and adjustment to negative events) is thought to promote positive affect. We examined the opposite path: could positive affect increase secondary control, particularly among individuals high in causal uncertainty, who stand to benefit from it the most? In two studies, participants completed a causal uncertainty scale, thought about a problem while listening to affect-inducing music or no music, and then completed items that assessed secondary control. In Study 1, the music induced positive or negative affect. In Study 2, the music induced affect that was high or low in activation and positive or negative in valence. In both studies, we found that positive affect-inducing music increased secondary control among high causal uncertainty participants. Furthermore, trait affect did not account for the effects of causal uncertainty, and music did not influence primary control. These findings show that secondary control can fluctuate as a function of state affect.

  1. Theory of coherent control with quantum light

    NASA Astrophysics Data System (ADS)

    Schlawin, Frank; Buchleitner, Andreas

    2017-01-01

    We develop a coherent control theory for multimode quantum light. It allows us to examine a fundamental problem in quantum optics: what is the optimal pulse form to drive a two-photon-transition? In formulating the question as a coherent control problem, we show that—and quantify how much—the strong frequency quantum correlations of entangled photons enhance the transition compared to shaped classical pulses. In ensembles of collectively driven two-level systems, such enhancement requires nonvanishing interactions.

  2. An Integrated Theory of Complement Control.

    ERIC Educational Resources Information Center

    Sag, Ivan A.; Pollard, Carl

    1991-01-01

    Presents an integrated theory of the syntactic and semantic representation of complements where the unexpressed subjects of the embedded verb-phrase complement are subject to certain interpretation restrictions. It is argued that the grammar of English controlled complements can be derived from the interaction of semantically based principles of…

  3. Comparing the neural correlates of affective and cognitive theory of mind using fMRI: Involvement of the basal ganglia in affective theory of mind.

    PubMed

    Bodden, Maren E; Kübler, Dorothee; Knake, Susanne; Menzler, Katja; Heverhagen, Johannes T; Sommer, Jens; Kalbe, Elke; Krach, Sören; Dodel, Richard

    2013-01-01

    Theory of Mind (ToM) is the ability to infer other people's mental states like intentions or desires. ToM can be differentiated into affective (i.e., recognizing the feelings of another person) and cognitive (i.e., inferring the mental state of the counterpart) subcomponents. Recently, subcortical structures such as the basal ganglia (BG) have also been ascribed to the multifaceted concept ToM and most BG disorders have been reported to elicit ToM deficits. In order to assess both the correlates of affective and cognitive ToM as well as involvement of the basal ganglia, 30 healthy participants underwent event-related fMRI scanning, neuropsychological testing, and filled in questionnaires concerning different aspects of ToM and empathy. Directly contrasting affective (aff) as well as cognitive (cog) ToM to the control (phy) condition, activation was found in classical ToM regions, namely parts of the temporal lobe including the superior temporal sulcus, the supplementary motor area, and parietal structures in the right hemisphere. The contrast aff > phy yielded additional activation in the orbitofrontal cortex on the right and the cingulate cortex, the precentral and inferior frontal gyrus and the cerebellum on the left. The right BG were recruited in this contrast as well. The direct contrast aff > cog showed activation in the temporoparietal junction and the cingulate cortex on the right as well as in the left supplementary motor area. The reverse contrast cog > aff however did not yield any significant clusters. In summary, affective and cognitive ToM partly share neural correlates but can also be differentiated anatomically. Furthermore, the BG are involved in affective ToM and thus their contribution is discussed as possibly providing a motor component of simulation processes, particularly in affective ToM.

  4. Would Controlled Substance Status Affect Steroid Trafficking?

    ERIC Educational Resources Information Center

    Cowart, Virginia S.

    1987-01-01

    Loss of control over the use of anabolic steriods had prompted the federal government to take steps to stem the black market manufacture and distribution of these drugs. However, these steps are likely to stop short of bestowing controlled substance status on steriods. (Author/CB)

  5. Anxiety and cognitive performance: attentional control theory.

    PubMed

    Eysenck, Michael W; Derakshan, Nazanin; Santos, Rita; Calvo, Manuel G

    2007-05-01

    Attentional control theory is an approach to anxiety and cognition representing a major development of Eysenck and Calvo's (1992) processing efficiency theory. It is assumed that anxiety impairs efficient functioning of the goal-directed attentional system and increases the extent to which processing is influenced by the stimulus-driven attentional system. In addition to decreasing attentional control, anxiety increases attention to threat-related stimuli. Adverse effects of anxiety on processing efficiency depend on two central executive functions involving attentional control: inhibition and shifting. However, anxiety may not impair performance effectiveness (quality of performance) when it leads to the use of compensatory strategies (e.g., enhanced effort; increased use of processing resources). Directions for future research are discussed.

  6. Control theory for scanning probe microscopy revisited.

    PubMed

    Stirling, Julian

    2014-01-01

    We derive a theoretical model for studying SPM feedback in the context of control theory. Previous models presented in the literature that apply standard models for proportional-integral-derivative controllers predict a highly unstable feedback environment. This model uses features specific to the SPM implementation of the proportional-integral controller to give realistic feedback behaviour. As such the stability of SPM feedback for a wide range of feedback gains can be understood. Further consideration of mechanical responses of the SPM system gives insight into the causes of exciting mechanical resonances of the scanner during feedback operation.

  7. Factors Affecting Lateral Stability and Controllability

    NASA Technical Reports Server (NTRS)

    Campbell, John P; Toll, Thomas A

    1948-01-01

    The effects on dynamic lateral stability and controllability of some of the important aerodynamic and mass characteristics are discussed and methods are presented for estimating the various stability parameters to be used in the calculation of the dynamic lateral stability of airplanes with swept and low-aspect-ratio wings.

  8. Vehicular Slip Ratio Control Using Nonlinear Control Theory

    NASA Astrophysics Data System (ADS)

    Ikeda, Yuichi; Nakajima, Takashi; Chida, Yuichi

    In this paper, we discuss integrated vehicle slip ratio control under both deceleration and acceleration without the need for controller switching, and also propose a design method for such an integrated slip ratio controller based on the slip ratio dynamics. When a vehicle switches from acceleration to deceleration and vice versa, the slip ratio varies discontinuously. Here, the slip ratio is approximated to a continuous function by using a sigmoid function. And a controller is then designed by using feedback linearization based on the approximated slip ratio. The stability of the designed control system is proven by Lyapunov stability theorem. Furthermore, we propose a robust control method based on a disturbance observer and sliding mode control theory. Finally, the effectiveness of the proposed control method is verified through numerical simulation.

  9. Local control theory applied to molecular photoassociation.

    PubMed

    Marquetand, Philipp; Engel, Volker

    2007-08-28

    Local control theory (LCT) is employed to achieve molecular photoassociation with shaped laser pulses. Within LCT, the control fields are constructed from the response of the system to the perturbation which makes them accessible to a straightforward interpretation. This is shown regarding the ground-state collision of H+F and H+I atoms. Different objectives are defined, which aim at the formation of vibrational cold or hot associated molecules, respectively. Results are presented for s-wave scattering, where the rotational degree of freedom is ignored and also for full scale calculations including rotations, in order to describe more realistic conditions.

  10. Stimulus-dependent amygdala involvement in affective theory of mind generation.

    PubMed

    Schmitgen, Mike M; Walter, Henrik; Drost, Sarah; Rückl, Sarah; Schnell, Knut

    2016-04-01

    Successful social interaction requires knowledge about another person's emotional states, represented in an affective theory of mind (ToM). This information can be acquired either directly or indirectly, i.e., by observing emotional facial expressions (EFE) or indirectly by inferring emotions through cognitive perspective taking. Therefore, it is of great interest how the function of the cortical ToM network and the limbic system in affective ToM depends on the presence of facial expressions. We addressed this question in a functional magnetic resonance imaging (fMRI) study. The experimental paradigm applied a well-established ToM cartoon task to test functional effects of EFE on the activation of the amygdala and the anterior ToM network during affective ToM judgments. During the task, 22 healthy participants had to judge the changes of the emotional state of the stories protagonist in the presence or absence of EFE. After quality control, 21 data sets entered the final analyses. The presence of EFE during affective ToM judgments was associated with shorter reaction times as well as increased activation of the right amygdala, most probably located in the basolateral nucleus (BLA), coincident with reduced activation of ToM-related regions of the prefrontal cortex. Psychophysiological interactions (PPI) revealed EFE-dependent modulation of connectivity between the right BLA and the contralateral ToM network regions. In combination with the functional interaction of EFE and affective ToM in the right amygdala, our data suggest a complementary but parallel organization of EFE processing and affective ToM. In this framework, the amygdala seems to act as an EFE detector when affective ToM judgments are demanded. Additionally, the facts that EFE induced exclusively right-sided amygdala activation and modulated the connectivity with the contralateral ToM network support the idea of a functional lateralization of stimulus driven components of affective ToM.

  11. Manual control theory and applications. [physiological and neurological applications

    NASA Technical Reports Server (NTRS)

    Sadoff, M.; Repa, B.

    1974-01-01

    Control theory, including manual control theory, and a review of some previous physiological and neurological applications of control theory and associated engineering concepts are reported. The discussion includes a specially tailored battery of critical control tasks that are being developed to monitor astronaut performance in long term orbital flight. The application of these concepts and tasks to patients with various neurological disorders is considered.

  12. Perspectives in Theory: Anthology of Theorists affecting the Educational World

    ERIC Educational Resources Information Center

    Bicking, Misty M., Ed.; Collins, Brian, Ed.; Fernett, Laura, Ed.; Taylor, Barbara, Ed.; Sutton, Kathleen, Ed.

    2008-01-01

    A compilation of research papers on theorists that affect the educational world are collected in this anthology. Twenty-one students, through the course of their education class, Social and Psychological Conditions of Learning--EDUC 320, researched and applied their knowledge in the elementary and secondary school environments. The contributing…

  13. Optimal control theory for sustainable environmental management.

    PubMed

    Shastri, Yogendra; Diwekar, Urmila; Cabezas, Heriberto

    2008-07-15

    Sustainable ecosystem management aims to promote the structure and operation of the human components of the system while simultaneously ensuring the persistence of the structures and operation of the natural component. Given the complexity of this task owing to the diverse temporal and spatial scales and multidisciplinary interactions, a systems theory approach based on sound mathematical techniques is essential. Two important aspects of this approach are formulation of sustainability-based objectives and development of the management strategies. Fisher information can be used as the basis of a sustainability hypothesis to formulate relevant mathematical objectives for disparate systems, and optimal control theory provides the means to derive time-dependent management strategies. Partial correlation coefficient analysis is an efficient technique to identify the appropriate control variables for policy development. This paper represents a proof of concept for this approach using a model system that includes an ecosystem, humans, a very rudimentary industrial process, and a very simple agricultural system. Formulation and solution of the control problems help in identifying the effective management options which offer guidelines for policies in real systems. The results also emphasize that management using multiple parameters of different nature can be distinctly effective.

  14. Linear control theory for gene network modeling.

    PubMed

    Shin, Yong-Jun; Bleris, Leonidas

    2010-09-16

    Systems biology is an interdisciplinary field that aims at understanding complex interactions in cells. Here we demonstrate that linear control theory can provide valuable insight and practical tools for the characterization of complex biological networks. We provide the foundation for such analyses through the study of several case studies including cascade and parallel forms, feedback and feedforward loops. We reproduce experimental results and provide rational analysis of the observed behavior. We demonstrate that methods such as the transfer function (frequency domain) and linear state-space (time domain) can be used to predict reliably the properties and transient behavior of complex network topologies and point to specific design strategies for synthetic networks.

  15. Aerospace plane guidance using geometric control theory

    NASA Technical Reports Server (NTRS)

    Van Buren, Mark A.; Mease, Kenneth D.

    1990-01-01

    A reduced-order method employing decomposition, based on time-scale separation, of the 4-D state space in a 2-D slow manifold and a family of 2-D fast manifolds is shown to provide an excellent approximation to the full-order minimum-fuel ascent trajectory. Near-optimal guidance is obtained by tracking the reduced-order trajectory. The tracking problem is solved as regulation problems on the family of fast manifolds, using the exact linearization methodology from nonlinear geometric control theory. The validity of the overall guidance approach is indicated by simulation.

  16. The quality control theory of aging.

    PubMed

    Ladiges, Warren

    2014-01-01

    The quality control (QC) theory of aging is based on the concept that aging is the result of a reduction in QC of cellular systems designed to maintain lifelong homeostasis. Four QC systems associated with aging are 1) inadequate protein processing in a distressed endoplasmic reticulum (ER); 2) histone deacetylase (HDAC) processing of genomic histones and gene silencing; 3) suppressed AMPK nutrient sensing with inefficient energy utilization and excessive fat accumulation; and 4) beta-adrenergic receptor (BAR) signaling and environmental and emotional stress. Reprogramming these systems to maintain efficiency and prevent aging would be a rational strategy for increased lifespan and improved health. The QC theory can be tested with a pharmacological approach using three well-known and safe, FDA-approved drugs: 1) phenyl butyric acid, a chemical chaperone that enhances ER function and is also an HDAC inhibitor, 2) metformin, which activates AMPK and is used to treat type 2 diabetes, and 3) propranolol, a beta blocker which inhibits BAR signaling and is used to treat hypertension and anxiety. A critical aspect of the QC theory, then, is that aging is associated with multiple cellular systems that can be targeted with drug combinations more effectively than with single drugs. But more importantly, these drug combinations will effectively prevent, delay, or reverse chronic diseases of aging that impose such a tremendous health burden on our society.

  17. Developmental Regulation with Progressive Vision Loss: Use of Control Strategies and Affective Well-Being

    ERIC Educational Resources Information Center

    Schilling, Oliver K.; Wahl, Hans-Werner; Boerner, Kathrin; Horowitz, Amy; Reinhardt, Joann P.; Cimarolli, Verena R.; Brennan-Ing, Mark; Heckhausen, Jutta

    2016-01-01

    The present study addresses older adults' developmental regulation when faced with progressive and irreversible vision loss. We used the motivational theory of life span development as a conceptual framework and examined changes in older adults' striving for control over everyday goal achievement, and their association with affective well-being,…

  18. Emotion, rationality, and decision-making: how to link affective and social neuroscience with social theory.

    PubMed

    Verweij, Marco; Senior, Timothy J; Domínguez D, Juan F; Turner, Robert

    2015-01-01

    In this paper, we argue for a stronger engagement between concepts in affective and social neuroscience on the one hand, and theories from the fields of anthropology, economics, political science, and sociology on the other. Affective and social neuroscience could provide an additional assessment of social theories. We argue that some of the most influential social theories of the last four decades-rational choice theory, behavioral economics, and post-structuralism-contain assumptions that are inconsistent with key findings in affective and social neuroscience. We also show that another approach from the social sciences-plural rationality theory-shows greater compatibility with these findings. We further claim that, in their turn, social theories can strengthen affective and social neuroscience. The former can provide more precise formulations of the social phenomena that neuroscientific models have targeted, can help neuroscientists who build these models become more aware of their social and cultural biases, and can even improve the models themselves. To illustrate, we show how plural rationality theory can be used to further specify and test the somatic marker hypothesis. Thus, we aim to accelerate the much-needed merger of social theories with affective and social neuroscience.

  19. Aerodynamic shape optimization using control theory

    NASA Technical Reports Server (NTRS)

    Reuther, James

    1996-01-01

    Aerodynamic shape design has long persisted as a difficult scientific challenge due its highly nonlinear flow physics and daunting geometric complexity. However, with the emergence of Computational Fluid Dynamics (CFD) it has become possible to make accurate predictions of flows which are not dominated by viscous effects. It is thus worthwhile to explore the extension of CFD methods for flow analysis to the treatment of aerodynamic shape design. Two new aerodynamic shape design methods are developed which combine existing CFD technology, optimal control theory, and numerical optimization techniques. Flow analysis methods for the potential flow equation and the Euler equations form the basis of the two respective design methods. In each case, optimal control theory is used to derive the adjoint differential equations, the solution of which provides the necessary gradient information to a numerical optimization method much more efficiently then by conventional finite differencing. Each technique uses a quasi-Newton numerical optimization algorithm to drive an aerodynamic objective function toward a minimum. An analytic grid perturbation method is developed to modify body fitted meshes to accommodate shape changes during the design process. Both Hicks-Henne perturbation functions and B-spline control points are explored as suitable design variables. The new methods prove to be computationally efficient and robust, and can be used for practical airfoil design including geometric and aerodynamic constraints. Objective functions are chosen to allow both inverse design to a target pressure distribution and wave drag minimization. Several design cases are presented for each method illustrating its practicality and efficiency. These include non-lifting and lifting airfoils operating at both subsonic and transonic conditions.

  20. Does the Financial Crisis Affect How Economic Theory Should Be Taught?

    ERIC Educational Resources Information Center

    Kafka, Alexander C., Comp.

    2008-01-01

    Professors of economics, business, and related fields were asked to answer the following question: Does the financial crisis affect how economic theory should be thought? This article presents some excerpts from their answers.

  1. Development of cognitive and affective control networks and decision making.

    PubMed

    Kar, Bhoomika R; Vijay, Nivita; Mishra, Shreyasi

    2013-01-01

    Cognitive control and decision making are two important research areas in the realm of higher-order cognition. Control processes such as interference control and monitoring in cognitive and affective contexts have been found to influence the process of decision making. Development of control processes follows a gradual growth pattern associated with the prolonged maturation of underlying neural circuits including the lateral prefrontal cortex, anterior cingulate, and the medial prefrontal cortex. These circuits are also involved in the control of processes that influences decision making, particularly with respect to choice behavior. Developmental studies on affective control have shown distinct patterns of brain activity with adolescents showing greater activation of amygdala whereas adults showing greater activity in ventral prefrontal cortex. Conflict detection, monitoring, and adaptation involve anticipation and subsequent performance adjustments which are also critical to complex decision making. We discuss the gradual developmental patterns observed in two of our studies on conflict monitoring and adaptation in affective and nonaffective contexts. Findings of these studies indicate the need to look at the differences in the effects of the development of cognitive and affective control on decision making in children and particularly adolescents. Neuroimaging studies have shown the involvement of separable neural networks for cognitive (medial prefrontal cortex and anterior cingulate) and affective control (amygdala, ventral medial prefrontal cortex) shows that one system can affect the other also at the neural level. Hence, an understanding of the interaction and balance between the cognitive and affective brain networks may be crucial for self-regulation and decision making during the developmental period, particularly late childhood and adolescence. The chapter highlights the need for empirical investigation on the interaction between the different aspects

  2. Emotion, rationality, and decision-making: how to link affective and social neuroscience with social theory

    PubMed Central

    Verweij, Marco; Senior, Timothy J.; Domínguez D., Juan F.; Turner, Robert

    2015-01-01

    In this paper, we argue for a stronger engagement between concepts in affective and social neuroscience on the one hand, and theories from the fields of anthropology, economics, political science, and sociology on the other. Affective and social neuroscience could provide an additional assessment of social theories. We argue that some of the most influential social theories of the last four decades—rational choice theory, behavioral economics, and post-structuralism—contain assumptions that are inconsistent with key findings in affective and social neuroscience. We also show that another approach from the social sciences—plural rationality theory—shows greater compatibility with these findings. We further claim that, in their turn, social theories can strengthen affective and social neuroscience. The former can provide more precise formulations of the social phenomena that neuroscientific models have targeted, can help neuroscientists who build these models become more aware of their social and cultural biases, and can even improve the models themselves. To illustrate, we show how plural rationality theory can be used to further specify and test the somatic marker hypothesis. Thus, we aim to accelerate the much-needed merger of social theories with affective and social neuroscience. PMID:26441506

  3. Application of control theory to dynamic systems simulation

    NASA Technical Reports Server (NTRS)

    Auslander, D. M.; Spear, R. C.; Young, G. E.

    1982-01-01

    The application of control theory is applied to dynamic systems simulation. Theory and methodology applicable to controlled ecological life support systems are considered. Spatial effects on system stability, design of control systems with uncertain parameters, and an interactive computing language (PARASOL-II) designed for dynamic system simulation, report quality graphics, data acquisition, and simple real time control are discussed.

  4. Action Theory, Control and Motivation: A Symposium.

    ERIC Educational Resources Information Center

    Eckensberger, L. H.; Meacham, J. A., Eds.

    1984-01-01

    Describes the symposium on action theory presented at the 1983 meeting of the International Society for the Study of Behavioral Development in Munich. The symposium included reactions to action theory from a variety of theoretical perspectives. (Author/RH)

  5. Cognitive control modulates preferential sensory processing of affective stimuli.

    PubMed

    Steinhauser, Marco; Flaisch, Tobias; Meinzer, Marcus; Schupp, Harald T

    2016-10-01

    Adaptive human behavior crucially relies on the ability of the brain to allocate resources automatically to emotionally significant stimuli. This ability has consistently been demonstrated by studies showing preferential processing of affective stimuli in sensory cortical areas. It is still unclear, however, whether this putatively automatic mechanism can be modulated by cognitive control processes. Here, we use functional magnetic resonance imaging (fMRI) to investigate whether preferential processing of an affective face distractor is suppressed when an affective distractor has previously elicited a response conflict in a word-face Stroop task. We analyzed this for three consecutive stages in the ventral stream of visual processing for which preferential processing of affective stimuli has previously been demonstrated: the striate area (BA 17), category-unspecific extrastriate areas (BA 18/19), and the fusiform face area (FFA). We found that response conflict led to a selective suppression of affective face processing in category-unspecific extrastriate areas and the FFA, and this effect was accompanied by changes in functional connectivity between these areas and the rostral anterior cingulate cortex. In contrast, preferential processing of affective face distractors was unaffected in the striate area. Our results indicate that cognitive control processes adaptively suppress preferential processing of affective stimuli under conditions where affective processing is detrimental because it elicits response conflict.

  6. Longitudinal relations between children's cognitive and affective theory of mind with reactive and proactive aggression.

    PubMed

    Austin, Gina; Bondü, Rebecca; Elsner, Birgit

    2017-02-20

    Aggression may be performed for different reasons, such as defending oneself (reactive aggression) or to reach egoistic aims (proactive aggression). It is a widely accepted notion that a lack of theory of mind (ToM) as a basic social competence should be linked to higher aggression, but findings on the developmental links between ToM and different functions of aggression have been inconsistent. One reason for this may be the failure of taking the bi-dimensionality of both ToM (cognitive vs. affective) and aggression (reactive vs. proactive) into account. In addition, the direction of effect remains unclear because longitudinal studies examining the mutual influences of both constructs are rare. Because research on ToM has focused on the preschool years, little is known about its development in middle childhood. Therefore, the present study examined the bi-directional developmental links of cognitive and affective ToM with reactive and proactive aggression in a longitudinal study in N = 232, 6- to 9-year-olds. Two points of measurement with a delay of about 1 year were conducted, and data were analyzed via cross-lagged structural equation modeling (SEM), controlling for age, gender, and information processing. In general, early ToM predicted later functions of aggression, but not vice versa. Cognitive and affective ToM were inversely related to later reactive aggression, but only affective but not cognitive ToM was inversely related to later proactive aggression. These findings emphasize the importance of ToM for the occurrence of aggression and of taking the bi-dimensionality of both constructs into account when investigating their developmental links across childhood.

  7. Dissociable early attentional control mechanisms underlying cognitive and affective conflicts

    PubMed Central

    Chen, Taolin; Kendrick, Keith M.; Feng, Chunliang; Sun, Shiyue; Yang, Xun; Wang, Xiaogang; Luo, Wenbo; Yang, Suyong; Huang, Xiaoqi; Valdés-Sosa, Pedro A.; Gong, Qiyong; Fan, Jin; Luo, Yue-Jia

    2016-01-01

    It has been well documented that cognitive conflict is sensitive to the relative proportion of congruent and incongruent trials. However, few studies have examined whether affective conflict processing is modulated as a function of proportion congruency (PC). To address this question we recorded event-related potentials (ERP) while subjects performed both cognitive and affective face-word Stroop tasks. By varying the proportion of congruent and incongruent trials in each block, we examined the extent to which PC impacts both cognitive and affective conflict control at different temporal stages. Results showed that in the cognitive task an anteriorly localized early N2 component occurred predominantly in the low proportion congruency context, whereas in the affective task it was found to occur in the high proportion congruency one. The N2 effects across the two tasks were localized to the dorsolateral prefrontal cortex, where responses were increased in the cognitive task but decreased in the affective one. Furthermore, high proportions of congruent items produced both larger amplitude of a posteriorly localized sustained potential component and a larger behavioral Stroop effect in cognitive and affective tasks. Our findings suggest that cognitive and affective conflicts engage early dissociable attentional control mechanisms and a later common conflict response system. PMID:27892513

  8. Dissociable early attentional control mechanisms underlying cognitive and affective conflicts.

    PubMed

    Chen, Taolin; Kendrick, Keith M; Feng, Chunliang; Sun, Shiyue; Yang, Xun; Wang, Xiaogang; Luo, Wenbo; Yang, Suyong; Huang, Xiaoqi; Valdés-Sosa, Pedro A; Gong, Qiyong; Fan, Jin; Luo, Yue-Jia

    2016-11-28

    It has been well documented that cognitive conflict is sensitive to the relative proportion of congruent and incongruent trials. However, few studies have examined whether affective conflict processing is modulated as a function of proportion congruency (PC). To address this question we recorded event-related potentials (ERP) while subjects performed both cognitive and affective face-word Stroop tasks. By varying the proportion of congruent and incongruent trials in each block, we examined the extent to which PC impacts both cognitive and affective conflict control at different temporal stages. Results showed that in the cognitive task an anteriorly localized early N2 component occurred predominantly in the low proportion congruency context, whereas in the affective task it was found to occur in the high proportion congruency one. The N2 effects across the two tasks were localized to the dorsolateral prefrontal cortex, where responses were increased in the cognitive task but decreased in the affective one. Furthermore, high proportions of congruent items produced both larger amplitude of a posteriorly localized sustained potential component and a larger behavioral Stroop effect in cognitive and affective tasks. Our findings suggest that cognitive and affective conflicts engage early dissociable attentional control mechanisms and a later common conflict response system.

  9. Neural systems supporting the control of affective and cognitive conflicts.

    PubMed

    Ochsner, Kevin N; Hughes, Brent; Robertson, Elaine R; Cooper, Jeffrey C; Gabrieli, John D E

    2009-09-01

    Although many studies have examined the neural bases of controlling cognitive responses, the neural systems for controlling conflicts between competing affective responses remain unclear. To address the neural correlates of affective conflict and their relationship to cognitive conflict, the present study collected whole-brain fMRI data during two versions of the Eriksen flanker task. For these tasks, participants indicated either the valence (affective task) or the semantic category (cognitive task) of a central target word while ignoring flanking words that mapped onto either the same (congruent) or a different (incongruent) response as the target. Overall, contrasts of incongruent > congruent trials showed that bilateral dorsal ACC, posterior medial frontal cortex, and dorsolateral pFC were active during both kinds of conflict, whereas rostral medial pFC and left ventrolateral pFC were differentially active during affective or cognitive conflict, respectively. Individual difference analyses showed that separate regions of rostral cingulate/ventromedial pFC and left ventrolateral pFC were positively correlated with the magnitude of response time interference. Taken together, the findings that controlling affective and cognitive conflicts depends upon both common and distinct systems have important implications for understanding the organization of control systems in general and their potential dysfunction in clinical disorders.

  10. Dynamical Systems and Control Theory Inspired by Molecular Biology

    DTIC Science & Technology

    2014-10-02

    AFRL-OSR-VA-TR-2014-0282 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY Eduardo Sontag RUTGERS THE STATE UNIVERSITY OF NEW JERSEY...Standard Form 298 (Re . 8-98) v Prescribed by ANSI Std. Z39.18 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY AFOSR FA9550-11-1-0247...is to develop new concepts, theory, and algorithms for control and signal processing using ideas inspired by molecular systems biology. Cell biology

  11. The effect of cognitive status and visuospatial performance on affective theory of mind in Parkinson's disease.

    PubMed

    McKinlay, Audrey; Albicini, Michelle; Kavanagh, Phillip S

    2013-01-01

    It is now well accepted that theory of mind (ToM) functioning is impaired in Parkinson's disease (PD) patients. However, what remain unknown are the functions that underlie this impairment. It has been suggested that cognitive skills may be key in this area of functioning; however, many of the cognitive tests used to assess this have relied on intact visuospatial abilities. This study aimed to examine whether deficits in ToM were generated by cognitive or visuospatial dysfunction and the mediating effect of visuospatial function on ToM performance. Fifty PD patients (31 male, 19 female; mean age = 66.34 years) and 49 healthy controls (16 male, 33 female; mean age = 67.29 years) completed a ToM task (reading the mind in the eyes) and visuospatial task (line orientation). The results revealed that current cognitive status was a significant predictor for performance on the ToM task, and that 54% of the total effect of cognitive status on ToM was mediated by visuospatial abilities. It was concluded that visuospatial functioning plays an important mediating role for the relationship between executive dysfunction and affective ToM deficits in PD patients, and that visuospatial deficits may directly contribute to the presence of affective ToM difficulties seen in individuals with PD.

  12. Actively Controlled Structures Theory. Volume 1. Theory of Design Methods

    DTIC Science & Technology

    1979-11-01

    Introduction to Circuits , Instruments and Electronics, New York: Harcourt, Brace & World, 1968. -,.,>i A-14 ^ ,’ sm APPENDIX B CONTROLLABILITY AND...34Controllability of Linear Dynamical Systems," Contributions to Differential Equations, Vol. 1, No. 2, pp. 189-213, 1962. 11. Zadeh, L.A. and C.A. Desoer

  13. Nonlinear Robust Control Theory and Applications

    DTIC Science & Technology

    1997-01-18

    and the other to the state-space realization theory developed mainly in the 󈨀s by Gilbert [2], Zadeh and Desoer [3], Kalman [4], Rosenbrock [5...3] L. Zadeh and C. Desoer , Linear System Theory - A State-Space Approach. McGraw- Hill, New York, 1963. [4] R. E. Kalman, "Mathematical descriptions

  14. Robust control systems design by H-infinity optimization theory

    NASA Technical Reports Server (NTRS)

    Chang, B. C.; Li, X. P.; Banda, S. S.; Yeh, H. H.

    1991-01-01

    In this paper, step-by-step procedures of applying the H-infinity theory to robust control systems design are given. The objective of the paper is to eliminate the possible difficulties a control engineer may encounter in applying H-infinity control theory and to clear up some misconceptions about H-infinity theory like high-gain controller and numerical obstacles, etc. An efficient algorithm is used to compute the optimal H-infinity norm. The Glover and Doyle (1988) controller formulas are slightly modified and used to construct an optimal controller without any numerical difficulties.

  15. A task control theory of mirror-touch synesthesia.

    PubMed

    Heyes, Cecilia; Catmur, Caroline

    2015-01-01

    Ward and Banissy's illuminating discussion of mirror-touch synesthesia (MTS) encourages research testing two alternatives to Threshold Theory: Their own Self-Other Theory, and "Task Control Theory". MTS may be due to abnormal mirror activity plus a domain-general, rather than a specifically social, impairment in the ability to privilege processing of task-relevant over task-irrelevant information.

  16. Optimal control theory for unitary transformations

    SciTech Connect

    Palao, Jose P.; Kosloff, Ronnie

    2003-12-01

    The dynamics of a quantum system driven by an external field is well described by a unitary transformation generated by a time-dependent Hamiltonian. The inverse problem of finding the field that generates a specific unitary transformation is the subject of study. The unitary transformation which can represent an algorithm in a quantum computation is imposed on a subset of quantum states embedded in a larger Hilbert space. Optimal control theory is used to solve the inversion problem irrespective of the initial input state. A unified formalism based on the Krotov method is developed leading to a different scheme. The schemes are compared for the inversion of a two-qubit Fourier transform using as registers the vibrational levels of the X {sup 1}{sigma}{sub g}{sup +} electronic state of Na{sub 2}. Raman-like transitions through the A {sup 1}{sigma}{sub u}{sup +} electronic state induce the transitions. Light fields are found that are able to implement the Fourier transform within a picosecond time scale. Such fields can be obtained by pulse-shaping techniques of a femtosecond pulse. Of the schemes studied, the square modulus scheme converges fastest. A study of the implementation of the Q qubit Fourier transform in the Na{sub 2} molecule was carried out for up to five qubits. The classical computation effort required to obtain the algorithm with a given fidelity is estimated to scale exponentially with the number of levels. The observed moderate scaling of the pulse intensity with the number of qubits in the transformation is rationalized.

  17. Translating theory into practice: integrating the affective and cognitive learning dimensions for effective instruction in engineering education

    NASA Astrophysics Data System (ADS)

    Alias, Maizam; Lashari, Tahira Anwar; Abidin Akasah, Zainal; Jahaya Kesot, Mohd.

    2014-03-01

    Learning in the cognitive domain is highly emphasised and has been widely investigated in engineering education. Lesser emphasis is placed on the affective dimension although the role of affects has been supported by research. The lack of understanding on learning theories and how they may be translated into classroom application of teaching and learning is one factor that contributes to this situation. This paper proposes a working framework for integrating the affective dimension of learning into engineering education that is expected to promote better learning within the cognitive domain. Four major learning theories namely behaviourism, cognitivism, socio-culturalism, and constructivism were analysed and how affects are postulated to influence cognition are identified. The affective domain constructs identified to be important are self-efficacy, attitude and locus of control. Based on the results of the analysis, a framework that integrates methodologies for achieving learning in the cognitive domain with the support of the affective dimension of learning is proposed. It is expected that integrated approach can be used as a guideline to engineering educators in designing effective and sustainable instructional material that would result in the effective engineers for future development.

  18. Right hemisphere involvement in depression: toward a neuropsychological theory of negative affective experiences.

    PubMed

    Otto, M W; Yeo, R A; Dougher, M J

    1987-10-01

    Several lines of inquiry provide converging evidence for a critical role for the right cerebral hemisphere in negative affective experiences. This research includes the assessment of affective consequences of both focal cerebral lesions and pharmacological inactivation of one or the other hemisphere, as well as experimental and physiological techniques assessing differential hemispheric activation. The specific nature of right hemispheric involvement is conceptualized as a tendency to become activated by aversive experiences, and once activated, to process stimuli in a manner consistent with the right hemisphere's more negative affective tone. A theory of right hemisphere involvement in depressive affect is presented in detail and its relevance to clinical phenomena, e.g., the co-occurrence of depression and pain, and sex differences in depression, is examined, as is congruence with cognitive theories of depression.

  19. Optimal control theory--closing the gap between theory and experiment.

    PubMed

    von den Hoff, Philipp; Thallmair, Sebastian; Kowalewski, Markus; Siemering, Robert; de Vivie-Riedle, Regina

    2012-11-14

    Optimal control theory and optimal control experiments are state-of-the-art tools to control quantum systems. Both methods have been demonstrated successfully for numerous applications in molecular physics, chemistry and biology. Modulated light pulses could be realized, driving these various control processes. Next to the control efficiency, a key issue is the understanding of the control mechanism. An obvious way is to seek support from theory. However, the underlying search strategies in theory and experiment towards the optimal laser field differ. While the optimal control theory operates in the time domain, optimal control experiments optimize the laser fields in the frequency domain. This also implies that both search procedures experience a different bias and follow different pathways on the search landscape. In this perspective we review our recent developments in optimal control theory and their applications. Especially, we focus on approaches, which close the gap between theory and experiment. To this extent we followed two ways. One uses sophisticated optimization algorithms, which enhance the capabilities of optimal control experiments. The other is to extend and modify the optimal control theory formalism in order to mimic the experimental conditions.

  20. An Experimental Test of the Affect-Regulation Theory of Bulimic Symptoms and Substance Use: A Randomized Trial

    PubMed Central

    Burton, Emily; Stice, Eric; Bearman, Sarah Kate; Rohde, Paul

    2006-01-01

    Objective: Conduct a randomized trial to test whether a cognitive behavioral intervention designed to decrease depressive symptoms produces subsequent decreases in bulimic and substance use symptoms. Methods: Female participants (N=145) with elevated depressive symptoms were randomly assigned to a 4-session depression intervention or a measurement-only condition and assessed through 6-month follow-up. Results: Relative to control participants, intervention participants showed decreases in depressive symptoms. Intervention participants also showed significantly greater reductions in bulimic symptoms, but not substance use, and change in depressive symptoms mediated this effect for bulimic symptoms. Discussion: Results provide experimental support for the theory that affect disturbances contribute to bulimic pathology, but do not support the affect regulation theory of substance use. PMID:16958129

  1. Relationships between digital signal processing and control and estimation theory

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1978-01-01

    Research directions in the fields of digital signal processing and modern control and estimation theory are discussed. Stability theory, linear prediction and parameter identification, system synthesis and implementation, two-dimensional filtering, decentralized control and estimation, and image processing are considered in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the disciplines.

  2. Could positive affect help engineer robot control systems?

    PubMed

    Quirin, Markus; Hertzberg, Joachim; Kuhl, Julius; Stephan, Achim

    2011-11-01

    Emotions have long been seen as counteracting rational thought, but over the last decades, they have been viewed as adaptive processes to optimize human (but also animal) behaviour. In particular, positive affect appears to be a functional aspect of emotions closely related to that. We argue that positive affect as understood in Kuhl's PSI model of the human cognitive architecture appears to have an interpretation in state-of-the-art hybrid robot control architectures, which might help tackle some open questions in the field.

  3. Pre-meal affective state and laboratory test meal intake in adolescent girls with loss of control eating.

    PubMed

    Ranzenhofer, Lisa M; Hannallah, Louise; Field, Sara E; Shomaker, Lauren B; Stephens, Mark; Sbrocco, Tracy; Kozlosky, Merel; Reynolds, James; Yanovski, Jack A; Tanofsky-Kraff, Marian

    2013-09-01

    Loss of control eating confers risk for excess weight gain and exacerbated disordered eating. Affect theory proposes that loss of control eating is used to cope with negative mood states. Self-report data suggest that negative affect may contribute to the etiology of loss of control eating, but this theory has not been well-tested using laboratory paradigms. We examined associations between pre-meal affective states and intake during a laboratory test meal. One-hundred and ten adolescent girls with reported loss of control eating whose body mass index fell between the 75th and 97th percentile for age and sex completed state mood ratings prior to a test-meal. Results indicated that pre-meal state negative affect was associated with greater carbohydrate and less protein consumption, as well as greater snack and dessert and less fruit and dairy intake. All girls experienced significant decreases in negative affect from pre- to post-meal, but intake during the meal was unassociated with post-meal affect. In support of affect theory, negative affective states reported among girls with loss of control may be a driving factor for increased energy-dense food intake, which may play a role in excess weight gain.

  4. Investigating Friendship Quality: An Exploration of Self-Control and Social Control Theories' Friendship Hypotheses

    ERIC Educational Resources Information Center

    Boman, John H., IV; Krohn, Marvin D.; Gibson, Chris L.; Stogner, John M.

    2012-01-01

    While associations with deviant peers are well understood to impact individual development, less is understood about the relationship between friendship quality and delinquency. Two criminological theories--social control theory and self-control theory--are able to offer an explanation for the latter relationship. Social control and self-control…

  5. Factors Affecting Christian Parents' School Choice Decision Processes: A Grounded Theory Study

    ERIC Educational Resources Information Center

    Prichard, Tami G.; Swezey, James A.

    2016-01-01

    This study identifies factors affecting the decision processes for school choice by Christian parents. Grounded theory design incorporated interview transcripts, field notes, and a reflective journal to analyze themes. Comparative analysis, including open, axial, and selective coding, was used to reduce the coded statements to five code families:…

  6. OPTIMAL CONTROL THEORY FOR SUSTAINABLE ENVIRONMENTAL MANAGEMENT

    EPA Science Inventory

    Sustainable management of the human and natural systems, taking into account their interactions, has become paramount. To achieve this complex multidisciplinary objective, systems theory based techniques prove useful. The proposed work is a step in that direction. Taking a food w...

  7. Function-valued adaptive dynamics and optimal control theory.

    PubMed

    Parvinen, Kalle; Heino, Mikko; Dieckmann, Ulf

    2013-09-01

    In this article we further develop the theory of adaptive dynamics of function-valued traits. Previous work has concentrated on models for which invasion fitness can be written as an integral in which the integrand for each argument value is a function of the strategy value at that argument value only. For this type of models of direct effect, singular strategies can be found using the calculus of variations, with singular strategies needing to satisfy Euler's equation with environmental feedback. In a broader, more mechanistically oriented class of models, the function-valued strategy affects a process described by differential equations, and fitness can be expressed as an integral in which the integrand for each argument value depends both on the strategy and on process variables at that argument value. In general, the calculus of variations cannot help analyzing this much broader class of models. Here we explain how to find singular strategies in this class of process-mediated models using optimal control theory. In particular, we show that singular strategies need to satisfy Pontryagin's maximum principle with environmental feedback. We demonstrate the utility of this approach by studying the evolution of strategies determining seasonal flowering schedules.

  8. Lay theory of race affects and moderates Asian Americans' responses toward American culture.

    PubMed

    No, Sun; Hong, Ying-yi; Liao, Hsin-Ya; Lee, Kyoungmi; Wood, Dustin; Chao, Melody Manchi

    2008-10-01

    People may hold different understandings of race that might affect how they respond to the culture of groups deemed to be racially distinct. The present research tests how this process is moderated by the minority individual's lay theory of race. An essentialist lay theory of race (i.e., that race reflects deep-seated, inalterable essence and is indicative of traits and ability) would orient racial minorities to rigidly adhere to their ethnic culture, whereas a social constructionist lay theory of race (i.e., that race is socially constructed, malleable, and arbitrary) would orient racial minorities to identify and cognitively assimilate toward the majority culture. To test these predictions, the authors conducted 4 studies with Asian American participants. The first 2 studies examine the effect of one's lay theory of race on perceived racial differences and identification with American culture. The last 2 studies tested the moderating effect of lay theory of race on identification and assimilation toward the majority American culture after this culture had been primed. The results generally supported the prediction that the social constructionist theory was associated with more perceived similarity between Asians and Americans and more consistent identification and assimilation toward American culture, compared with the essentialist theory.

  9. Costs of children--benefit theory and population control.

    PubMed

    Tian, X

    1989-01-01

    In order to stem the rising fertility and growth rates in China, new theories and measures are needed. The author suggests new insights into the relationships between reproductive behavior and economic interests, regulation of individual reproductive behavior by such economic interests, and governmental performance with these interests in mind. Topics are devoted to the benefit theory about the costs of children, trends in Chinese children's costs and benefits, and family planning (FP) based on children's costs and benefits. Natural biological law governed people's reproductive behavior and the number of offspring until there was control over human reproduction. Factors which determine the desired number of children can be economic, cultural, political, historical, or geographical. In modern times and with the commercialism of society, children have been sometimes viewed as commodities and Western economists (Becker and Leibenstein) have theorized the cost benefit ratio to parents. Expected positive benefits are support, labor force contribution, and family happiness. Negative benefits are the direct and indirect costs in time and money raising children. Children are produced where benefits are positive, and where benefits and costs are equal, circumstances will determine the result. No children will be produced when costs exceed benefits. The concept of net costs is described. Chinese trends indicate a direction toward a market oriented economy. Instead of following Western theory, as economic development has advanced rapidly the value of children has grown. The reasons are explained as marginal children may still bring benefits in a market where the function of regulation of a labor market is limited, children still render better support for their parents without a developed social security system, and boys are expected to secure their families fortunes during the changing economic conditions. The author recognizes that other conditions such as the number of

  10. Approximate Newton-type methods via theory of control

    NASA Astrophysics Data System (ADS)

    Yap, Chui Ying; Leong, Wah June

    2014-12-01

    In this paper, we investigate the possible use of control theory, particularly theory on optimal control to derive some numerical methods for unconstrained optimization problems. Based upon this control theory, we derive a Levenberg-Marquardt-like method that guarantees greatest descent in a particular search region. The implementation of this method in its original form requires inversion of a non-sparse matrix or equivalently solving a linear system in every iteration. Thus, an approximation of the proposed method via quasi-Newton update is constructed. Numerical results indicate that the new method is more effective and practical.

  11. Climate affects predator control of an herbivore outbreak.

    PubMed

    Preisser, Evan L; Strong, Donald R

    2004-05-01

    Herbivore outbreaks and the accompanying devastation of plant biomass can have enormous ecological effects. Climate directly affects such outbreaks through plant stress or alterations in herbivore life-history traits. Large-scale variation in climate can indirectly affect outbreaks through trophic interactions, but the magnitude of such effects is unknown. On the California coast, rainfall in years during and immediately previous to mass lupine mortality was two-thirds that of years without such mortality. However, neither mature lupines nor their root-feeding herbivores are directly affected by annual variation in rainfall. By increasing soil moisture to levels characteristic of summers following El Niño/Southern Oscillation (ENSO) events, we increased persistence of a predator (the entomopathogenic nematode Heterorhabditis marelatus). This led to suppression of an outbreak of the herbivorous moth Hepialus californicus, indirectly protecting bush lupine (Lupinus arboreus). Our results are consistent with the marine-oriented Menge-Sutherland hypothesis (Menge and Sutherland 1987) that abiotic stress has greater effects on higher than on lower trophic levels. The mechanisms producing these results differ from those proposed by Menge-Sutherland, however, highlighting differences between trophic processes in underground and terrestrial/marine food webs. Our evidence suggests that herbivore outbreaks and mass lupine mortality are indirectly affected by ENSO's facilitation of top-down control in this food web.

  12. Design of a Helicopter Stability and Control Augmentation System Using Optimal Control Theory.

    DTIC Science & Technology

    technique is described for the design of multivariable feedback controllers based upon results in optimal control theory . For a specified performance...helicopter flight envelope. The results show that optimal control theory can be used to design a helicopter stability and control augmentation system

  13. Lagrange Duality Theory for Convex Control Problems,

    DTIC Science & Technology

    to be optimal is also given. The dual variables p and v corresponding to the system dynamics and state constraints are proved to be of bounded ... variation while the multiplier corresponding to the control constraints is proved to lie in 1. Finally, a control and state minimum principle is proved. If

  14. The Application of Layer Theory to Design: The Control Layer

    ERIC Educational Resources Information Center

    Gibbons, Andrew S.; Langton, Matthew B.

    2016-01-01

    A theory of design layers proposed by Gibbons ("An Architectural Approach to Instructional Design." Routledge, New York, 2014) asserts that each layer of an instructional design is related to a body of theory closely associated with the concerns of that particular layer. This study focuses on one layer, the control layer, examining…

  15. Risk for Depression and Anxiety in Youth: The Interaction between Negative Affectivity, Effortful Control, and Stressors.

    PubMed

    Gulley, Lauren D; Hankin, Benjamin L; Young, Jami F

    2016-02-01

    Theories of temperament suggest that individual differences in affective reactivity (e.g., negative affectivity) may confer risk for internalizing psychopathology in youth and that self-regulatory aspects of temperament (e.g., effortful control) may protect against the deleterious effects of high negative affective reactivity. However, no study to date has examined how the relationship between temperament and youth internalizing psychopathology may be moderated by stress. The current study used a prospective longitudinal design to test the interaction of temperament (e.g., negative affectivity and effortful control) and stressors as a predictor of youth (ages 7-16; 56 % female; N = 576) depressive and anxious symptoms over a 3-month period. Findings show that at low levels of stress, high levels of effortful control protect against the development of depressive and anxious symptoms among youth with high levels of negative affectivity. However, at high levels of stress, this buffering effect is not observed. Gender and grade did not moderate this relationship. Overall, findings extend current understanding of how the interaction of individual psychosocial vulnerabilities and environmental factors may confer increased or decreased risk for depressive and anxious symptoms.

  16. Risk for Depression and Anxiety in Youth: The Interaction between Negative Affectivity, Effortful Control, and Stressors

    PubMed Central

    Gulley, Lauren D.; Hankin, Benjamin L.; Young, Jami F.

    2015-01-01

    Theories of temperament suggest that individual differences in affective reactivity (e.g., negative affectivity) may confer risk for internalizing psychopathology in youth and that self-regulatory aspects of temperament (e.g., effortful control) may protect against the deleterious effects of high negative affective reactivity. However, no study to date has examined how the relationship between temperament and youth internalizing psychopathology may be moderated by stress. The current study used a prospective longitudinal design to test the interaction of temperament (e.g., negative affectivity and effortful control) and stressors as a predictor of youth (ages 7–16; 56% female; N = 576) depressive and anxious symptoms over a 3-month period. Findings show that at low levels of stress, high levels of effortful control protect against the development of depressive and anxious symptoms among youth with high levels of negative affectivity. However, at high levels of stress, this buffering effect is not observed. Gender and grade did not moderate this relationship. Overall, findings extend current understanding of how the interaction of individual psychosocial vulnerabilities and environmental factors may confer increased or decreased risk for depressive and anxious symptoms. PMID:25870113

  17. Links Among Cognitive Empathy, Theory of Mind, and Affective Perspective Taking by Young Children.

    PubMed

    Bensalah, Leïla; Caillies, Stéphanie; Anduze, Marion

    2016-01-01

    The authors investigated the development of the affective, cognitive, and behavioral components of empathy in preschoolers, specifically examining how cognitive empathy is linked to theory of mind and affective perspective taking. Participants were 158 children aged 4-6 years. They listened to narratives and then answered questions about the protagonists' emotions. The affective component was probed with the question, "How do you feel seeing the little girl/boy?"; the cognitive component with the question, "Why do you feel [emotion shared with the character]?"; and the behavioral one with the question, "What would you do if you were next to the little boy/girl [experiencing an emotional scenario]?" Results revealed a developmental sequence in the self-focused attribution of cognitive empathy, and a trend toward a developmental sequence for behavioral empathy, which underwent a slight linear increase between 4 and 6 years old. Affective empathy remained stable. More interestingly, they showed that cognitive empathy is linked to both theory of mind and affective perspective taking.

  18. Hybrid LTA vehicle controllability as affected by buoyancy ratio

    NASA Technical Reports Server (NTRS)

    Meyers, D. N.; Kubicki, P.; Tarczynski, T.; Fairbanks, A.; Piasecki, F. N.

    1979-01-01

    The zero and low speed controllability of heavy lift airships under various wind conditions as affected by the buoyancy ratio are investigated. A series of three hybrid LTA vehicls were examined, each having a dynamic thrust system comprised of four H-34 helicopters, but with buoyant envelopes of different volumes (and hence buoyancies), and with varying percentage of helium inflation and varying useful loads (hence gross weights). Buoyancy ratio, B, was thus examined varying from approximately 0.44 to 1.39. For values of B greater than 1.0, the dynamic thrusters must supply negative thrust (i.e. downward).

  19. Theory, Methods, and Applications of Nonlinear Control

    DTIC Science & Technology

    2012-08-29

    help capture hybrid settings where the system switches between different modes of operation by moving between different regions of the state space... Lyapunov -Krasovskii functionals. The UAV work can be applied when there are rate constraints on the controls (which are constant bounds on the rate of... Lyapunov Functions, Communications and Control Engineering Series, Springer-Verlag London Ltd., London, UK, 2009. [MMZ11] Malisoff, M., F. Mazenc, and

  20. A control theory approach to clock steering techniques.

    PubMed

    Farina, Marcello; Galleani, Lorenzo; Tavella, Patrizia; Bittanti, Sergio

    2010-10-01

    Several clock and time scale steering methods have been developed according to different viewpoints by various time laboratories. By resorting to control theory ideas, we propose a common theoretical framework encompassing these methods. A comparison of the most common steering methodologies, namely, the classical steering approach, the GPS bang-bang method, and the linear quadratic Gaussian technique, is carried out. We believe that the use of control theory methods can potentially lead to a better understanding of clock steering algorithms.

  1. Project Management Using Modern Guidance, Navigation and Control Theory

    NASA Technical Reports Server (NTRS)

    Hill, Terry

    2010-01-01

    The idea of control theory and its application to project management is not new, however literature on the topic and real-world applications is not as readily available and comprehensive in how all the principals of Guidance, Navigation and Control (GN&C) apply. This paper will address how the fundamental principals of modern GN&C Theory have been applied to NASA's Constellation Space Suit project and the results in the ability to manage the project within cost, schedule and budget. A s with physical systems, projects can be modeled and managed with the same guiding principles of GN&C as if it were a complex vehicle, system or software with time-varying processes, at times non-linear responses, multiple data inputs of varying accuracy and a range of operating points. With such systems the classic approach could be applied to small and well-defined projects; however with larger, multi-year projects involving multiple organizational structures, external influences and a multitude of diverse resources, then modern control theory is required to model and control the project. The fundamental principals of G N&C stated that a system is comprised of these basic core concepts: State, Behavior, Control system, Navigation system, Guidance and Planning Logic, Feedback systems. The state of a system is a definition of the aspects of the dynamics of the system that can change, such as position, velocity, acceleration, coordinate-based attitude, temperature, etc. The behavior of the system is more of what changes are possible rather than what can change, which is captured in the state of the system. The behavior of a system is captured in the system modeling and if properly done, will aid in accurate system performance prediction in the future. The Control system understands the state and behavior of the system and feedback systems to adjust the control inputs into the system. The Navigation system takes the multiple data inputs and based upon a priori knowledge of the input

  2. Closed Loop Vibrational Control: Theory and Applications

    DTIC Science & Technology

    1993-10-01

    63 4.13 b Horizontal acceleration of helicopter in flight with wind gust ............. 63 4 STATEMENT OF THE PROBLEM The goal of this thesis is the...In this thesis , we treat the above problem by considering a linear time-invariant SISO system of the form S= Ax(t) + Biu(t) + B 2w(t) , (0.5) y(t...this choice does not affect the qualitative results of this thesis . Using this model, this thesis gives a phenomenological explanation of the

  3. Lie theory and control systems defined on spheres

    NASA Technical Reports Server (NTRS)

    Brockett, R. W.

    1972-01-01

    It is shown that in constructing a theory for the most elementary class of control problems defined on spheres, some results from the Lie theory play a natural role. To understand controllability, optimal control, and certain properties of stochastic equations, Lie theoretic ideas are needed. The framework considered here is the most natural departure from the usual linear system/vector space problems which have dominated control systems literature. For this reason results are compared with those previously available for the finite dimensional vector space case.

  4. Motor control theories and their applications.

    PubMed

    Latash, Mark L; Levin, Mindy F; Scholz, John P; Schöner, Gregor

    2010-01-01

    We describe several influential hypotheses in the field of motor control including the equilibrium-point (referent configuration) hypothesis, the uncontrolled manifold hypothesis, and the idea of synergies based on the principle of motor abundance. The equilibrium-point hypothesis is based on the idea of control with thresholds for activation of neuronal pools; it provides a framework for analysis of both voluntary and involuntary movements. In particular, control of a single muscle can be adequately described with changes in the threshold of motor unit recruitment during slow muscle stretch (threshold of the tonic stretch reflex). Unlike the ideas of internal models, the equilibrium-point hypothesis does not assume neural computations of mechanical variables. The uncontrolled manifold hypothesis is based on the dynamic system approach to movements; it offers a toolbox to analyze synergic changes within redundant sets of elements related to stabilization of potentially important performance variables. The referent configuration hypothesis and the principle of abundance can be naturally combined into a single coherent scheme of control of multi-element systems. A body of experimental data on healthy persons and patients with movement disorders are reviewed in support of the mentioned hypotheses. In particular, movement disorders associated with spasticity are considered as consequences of an impaired ability to shift threshold of the tonic stretch reflex within the whole normal range. Technical details and applications of the mentioned hypo-theses to studies of motor learning are described. We view the mentioned hypotheses as the most promising ones in the field of motor control, based on a solid physical and neurophysiological foundation.

  5. Sound as Affective Design Feature in Multimedia Learning--Benefits and Drawbacks from a Cognitive Load Theory Perspective

    ERIC Educational Resources Information Center

    Königschulte, Anke

    2015-01-01

    The study presented in this paper investigates the potential effects of including non-speech audio such as sound effects into multimedia-based instruction taking into account Sweller's cognitive load theory (Sweller, 2005) and applied frameworks such as the cognitive theory of multimedia learning (Mayer, 2005) and the cognitive affective theory of…

  6. Toward a common theory for learning from reward, affect, and motivation: the SIMON framework

    PubMed Central

    Madan, Christopher R.

    2013-01-01

    While the effects of reward, affect, and motivation on learning have each developed into their own fields of research, they largely have been investigated in isolation. As all three of these constructs are highly related, and use similar experimental procedures, an important advance in research would be to consider the interplay between these constructs. Here we first define each of the three constructs, and then discuss how they may influence each other within a common framework. Finally, we delineate several sources of evidence supporting the framework. By considering the constructs of reward, affect, and motivation within a single framework, we can develop a better understanding of the processes involved in learning and how they interplay, and work toward a comprehensive theory that encompasses reward, affect, and motivation. PMID:24109436

  7. Damage to the left ventromedial prefrontal cortex impacts affective theory of mind

    PubMed Central

    Leopold, Anne; dal Monte, Olga; Pardini, Matteo; Pulaski, Sarah J.; Solomon, Jeffrey; Grafman, Jordan

    2012-01-01

    Studies investigating theory of mind (ToM) abilities (i.e. ability to understand and predict others’ mental states) have revealed that affective and cognitive functions play a significant role and that each of those functions are associated with distinct neural networks. Cognitive facets of ToM have implicated the medial prefrontal cortex, temporo-parietal junction and the anterior paracingulate cortex, whereas affective facets have implicated the ventromedial prefrontal cortex (vmPFC). Although the vmPFC has repeatedly shown to be critical for affective functions, knowledge regarding the exact role of the left and right vmPFC in affective ToM is still obscure. Here, we compared performances of 30 patients with left, right and bilateral vmPFC lesions to two comparison groups (one without and one with brain injuries) on the Faux Pas Recognition task measuring the facets of ToM. We also investigated whether any deficits may be associated with other emotional measures, namely emotional empathy and emotional intelligence. Our results extend earlier findings by showing that the vmPFC is associated with abilities in affective ToM. More importantly, our results revealed that the left, and not the right vmPFC as indicated previously, is involved in affective ToM and that this deficit is associated with emotional intelligence. PMID:22021651

  8. Boiler Control Systems Theory of Operation Manual.

    DTIC Science & Technology

    1983-02-01

    NEUMATIC 14NOR RPUr OUTFUT =161 IG~NAL. ISIGINAL (0-3o PslIq) S14NAL FiWMr qJAL IS TF le PROPOK1ONAL TO STEAM STM PRESSURE SAM I AS IN ~-’ HEADEX PRESURE...effective on every start. Any condition following flame failure. The control recycles each which will cause the flame relay to hold in during the time...motor, ignition damper during purge, non- recycling limit and air system, fuel valve, and modulator system in a proper flow interlocks and spark cut-off

  9. Helicopter trajectory planning using optimal control theory

    NASA Technical Reports Server (NTRS)

    Menon, P. K. A.; Cheng, V. H. L.; Kim, E.

    1988-01-01

    A methodology for optimal trajectory planning, useful in the nap-of-the-earth guidance of helicopters, is presented. This approach uses an adjoint-control transformation along with a one-dimensional search scheme for generating the optimal trajectories. In addition to being useful for helicopter nap-of-the-earth guidance, the trajectory planning solution is of interest in several other contexts, such as robotic vehicle guidance and terrain-following guidance for cruise missiles and aircraft. A distinguishing feature of the present research is that the terrain constraint and the threat envelopes are incorporated in the equations of motion. Second-order necessary conditions are examined.

  10. Kalman meets neuron - the intersection of control theory and neuroscience

    NASA Astrophysics Data System (ADS)

    Schiff, Steven

    2009-03-01

    Since the 1950s, we have developed mature theories of modern control theory and computational neuroscience with almost no interaction between these disciplines. With the advent of computationally efficient nonlinear Kalman filtering techniques, along with improved neuroscience models which provide increasingly accurate reconstruction of dynamics in a variety of important normal and disease states in the brain, the prospects for a synergistic interaction between these fields are now strong. I will show recent examples of the use of nonlinear control theory for the assimilation and control of single neuron dynamics, a novel framework for dynamic clamp, the modulation of oscillatory wave dynamics in brain cortex, a control framework for Parkinsonian dynamics and seizures, and the use of optimized parameter model networks to assimilate complex network data.

  11. Hierarchical control of ride height system for electronically controlled air suspension based on variable structure and fuzzy control theory

    NASA Astrophysics Data System (ADS)

    Xu, Xing; Zhou, Kongkang; Zou, Nannan; Jiang, Hong; Cui, Xiaoli

    2015-09-01

    The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control (VSC) technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system.

  12. Engagement & Disengagement in Mutual-Help Addiction Recovery Housing: A Test of Affective Events Theory

    PubMed Central

    Beasley, Christopher R.; Jason, Leonard A.

    2016-01-01

    Engagement and disengagement in addiction recovery settings are important for these communities and their members. This study tested an Affective Events Theory (AET) model of these constructs in the Oxford House network of recovery homes. Residents’ congruence with their home (P-E fit) was hypothesized to directly influence behavior that supported the house and other residents—citizenship behavior. We further hypothesized P-E fit would be related to member intentions to leave, with attitudes toward the home mediating that relationship. To assess this, we administered a cross-sectional national survey to 296 residents of 83 randomly selected Oxford Houses. Although the AET model demonstrated good fit with the data, an alternative model fit better. This alternative model suggested an additional indirect relationship between P-E fit and citizenship mediated by attitudes. Results suggested affective experiences such as feeling like one fits with a community may influence engagement and disengagement. There appears to be a direct influence of fit on citizenship behavior and an indirect influence of fit through recovery home attitudes on both citizenship and how intentions to leave the home. We conclude affective experiences could be important for community engagement and disengagement but AET may need to integrate cognitive dissonance theory. PMID:25791917

  13. Engagement and disengagement in mutual-help addiction recovery housing: a test of affective events theory.

    PubMed

    Beasley, Christopher R; Jason, Leonard A

    2015-06-01

    This study tested an affective events theory (AET) model in the Oxford House network of recovery homes. Residents' congruence with their home (P-E fit) was hypothesized to directly influence behavior that supported the house and other residents-citizenship behavior. We further hypothesized P-E fit would be related to member intentions to leave, with attitudes toward the home mediating that relationship. To assess this, we administered a cross-sectional national survey to 296 residents of 83 randomly selected Oxford Houses. Although the AET model demonstrated good fit with the data, an alternative model fit better. This alternative model suggested an additional indirect relationship between P-E fit and citizenship mediated by attitudes. Results suggested affective experiences such as feeling like one fits with a community may influence engagement and disengagement. There appears to be a direct influence of fit on citizenship behavior and an indirect influence of fit through recovery home attitudes on both citizenship and intentions to leave the home. We conclude affective experiences could be important for community engagement and disengagement but AET may need to integrate cognitive dissonance theory.

  14. Personality and racial/ethnic relations: a perspective from Cognitive-Affective Personality System (CAPS) Theory.

    PubMed

    Mendoza-Denton, Rodolfo; Goldman-Flythe, Michelle

    2009-10-01

    The five articles in this special section examine personality and racial/ethnic relations from the perspective of Mischel and Shoda's Cognitive-Affective Personality System (CAPS) Theory. In this introductory piece, we first provide a primer on CAPS theory. In particular, we try to highlight the role that context plays in the construction and manifestation of personality as well as the dynamic ways that people interpret and react to input from their environment. We then review research on race-based rejection sensitivity as a programmatic illustration of the role expectancies play in racial/ethnic relations. Finally, we summarize and tie together the articles that comprise this section via a set of emergent themes that are common to the present contributions.

  15. Implicit theory manipulations affecting efficacy of a smartphone application aiding speech therapy for Parkinson's patients.

    PubMed

    Nolan, Peter; Hoskins, Sherria; Johnson, Julia; Powell, Vaughan; Chaudhuri, K Ray; Eglin, Roger

    2012-01-01

    A Smartphone speech-therapy application (STA) is being developed, intended for people with Parkinson's disease (PD) with reduced implicit volume cues. The STA offers visual volume feedback, addressing diminished auditory cues. Users are typically older adults, less familiar with new technology. Domain-specific implicit theories (ITs) have been shown to result in mastery or helpless behaviors. Studies manipulating participants' implicit theories of 'technology' (Study One), and 'ability to affect one's voice' (Study Two), were coordinated with iterative STA test-stages, using patients with PD with prior speech-therapist referrals. Across studies, findings suggest it is possible to manipulate patients' ITs related to engaging with a Smartphone STA. This potentially impacts initial application approach and overall effort using a technology-based therapy.

  16. Oculomotor tasks affect differently postural control in healthy children.

    PubMed

    Bucci, Maria Pia; Ajrezo, Layla; Wiener-Vacher, Sylvette

    2015-11-01

    Eye movements affect postural stability in children. The present study focuses on the effect of different types of eye movements on postural stability in healthy children. Both eye movements and postural stability have been recorded in 51 healthy children from 6.3 to 15.5 years old. Eye movements were recorded binocularly with a video oculography (MobilEBT(®)), and postural stability was measured while child was standing on a force platform (TechnoConcept(®)). Children performed three oculomotor tasks: saccades, pursuits and reading a text silently. We measured the number of saccades made in the three oculomotor tasks, the number of words read, and the surface area, the length and mean velocity of the center of pressure (CoP). According to previous studies, postural control improves with age until 10-12 years. Saccades toward a target as well as during a reading task reduce significantly the CoP displacement and its velocity, while during pursuit eye movements all children increase postural parameters (i.e., the surface area, the length and mean velocity of the CoP). These results suggest the presence of an interaction between the oculomotor control and the postural system. Visual attention to perform saccades (to stationary targets or to words) influences postural stability more than the frequency of saccade triggering does.

  17. Cooperative control theory and integrated flight and propulsion control

    NASA Technical Reports Server (NTRS)

    Schmidt, David K.; Schierman, John D.

    1994-01-01

    This report documents the activities and research results obtained under a grant (NAG3-998) from the NASA Lewis Research Center. The focus of the research was the investigation of dynamic interactions between airframe and engines for advanced ASTOVL aircraft configurations, and the analysis of the implications of these interactions on the stability and performance of the airframe and engine control systems. In addition, the need for integrated flight and propulsion control for such aircraft was addressed. The major contribution of this research was the exposition of the fact that airframe and engine interactions could be present, and their effects could include loss of stability and performance of the control systems. Also, the significance of two directional, as opposed to one-directional, coupling was identified and explained. A multi variable stability and performance analysis methodology was developed, and applied to several candidate aircraft configurations. Also exposed was the fact that with interactions present along with some integrated control approaches, the engine command/limiting logic (which represents an important non-linear component of the engine control system) can impact closed-loop airframe/engine system stability. Finally, a brief investigation of control-law synthesis techniques appropriate for the class of systems was pursued, and it was determined that multi variable techniques, included model-following formulations of LQG and/or H (infinity) methods showed promise. However, for practical reasons, decentralized control architectures are preferred, which is an architecture incompatible with these synthesis methods.

  18. Project Management Using Modern Guidance, Navigation and Control Theory

    NASA Technical Reports Server (NTRS)

    Hill, Terry R.

    2011-01-01

    of the system. The behavior of a system, as captured in the system modeling, when properly done will aid in accurately predicting future system performance. The Feedback Control system understands the state and behavior of the system and uses feedback to adjust control inputs into the system. The feedback, which is the right arm of the Control system, allows change to be affected in the overall system; it therefore is important to not only correctly identify the system feedback inputs, but also the system response to the feedback inputs. The Navigation system takes multiple data inputs and based on a priori knowledge of the inputs, develops a statistically based weighting of the inputs and measurements to determine the system's state. Guidance and Planning Logic of the system, complete with an understanding of where the system is (provided by the Navigation system), will in turn determine where the system needs to be and how to get it there. With any system/project, it is critical that the objective of the system/project be clearly defined -- not only to plan but to measure performance and to aid in guiding the system or the project. The system principles discussed above, which can be and have been applied to the current CxP space suit development project, can also be mapped to real-world constituents, thus allowing project managers to apply systems theories that are well defined in engineering and mathematics to a discipline (i.e., Project Management) that historically has been based in personal experience and intuition. This mapping of GN&C theory to Project Management will, in turn, permit a direct, methodical approach to Project Management, planning and control providing a tool to help predict (and guide) performance and an understanding of the project constraints, how the project can be controlled, and the impacts to external influences and inputs. This approach, to a project manager, flows down to the three bottom-line variables of cost, schedule, and scope

  19. The Role of Modern Control Theory in the Design of Controls for Aircraft Turbine Engines

    NASA Technical Reports Server (NTRS)

    Zeller, J.; Lehtinen, B.; Merrill, W.

    1982-01-01

    Accomplishments in applying Modern Control Theory to the design of controls for advanced aircraft turbine engines were reviewed. The results of successful research programs are discussed. Ongoing programs as well as planned or recommended future thrusts are also discussed.

  20. Cooperative control theory and integrated flight and propulsion control

    NASA Technical Reports Server (NTRS)

    Schmidt, David K.; Schierman, John D.

    1995-01-01

    The major contribution of this research was the exposition of the fact that airframe and engine interactions could be present, and their effects could include loss of stability and performance of the control systems. Also, the significance of two directional, as opposed to one-directional, coupling was identified and explained. A multivariable stability and performance analysis methodology was developed, and applied to several candidate aircraft configurations. In these example evaluations, the significance of these interactions was underscored. Also exposed was the fact that with interactions present along with some integrated control approaches, the engine command/limiting logic (which represents an important nonlinear component of the engine control system) can impact closed-loop airframe/engine system stability. Finally, a brief investigation of control-law synthesis techniques appropriate for the class of systems was pursued, and it was determined that multivariable techniques, including model-following formulations of LQG and/or H infinity methods, showed promise. However, for practical reasons, decentralized control architectures are preferred, which is an architecture incompatible with these synthesis methods. The major contributions of the second phase of the grant was the development of conditions under which no decentralized controller could achieve closed loop system requirements on stability and/or performance. Sought were conditions that depended only on properties of the plant and the requirement, and independent of any particular control law or synthesis approach. Therefore, they could be applied a priori, before synthesis of a candidate control law. Under this grant, such conditions were found regarding stability, and encouraging initial results were obtained regarding performance.

  1. A Theory of Cheap Control in Embodied Systems.

    PubMed

    Montúfar, Guido; Ghazi-Zahedi, Keyan; Ay, Nihat

    2015-09-01

    We present a framework for designing cheap control architectures of embodied agents. Our derivation is guided by the classical problem of universal approximation, whereby we explore the possibility of exploiting the agent's embodiment for a new and more efficient universal approximation of behaviors generated by sensorimotor control. This embodied universal approximation is compared with the classical non-embodied universal approximation. To exemplify our approach, we present a detailed quantitative case study for policy models defined in terms of conditional restricted Boltzmann machines. In contrast to non-embodied universal approximation, which requires an exponential number of parameters, in the embodied setting we are able to generate all possible behaviors with a drastically smaller model, thus obtaining cheap universal approximation. We test and corroborate the theory experimentally with a six-legged walking machine. The experiments indicate that the controller complexity predicted by our theory is close to the minimal sufficient value, which means that the theory has direct practical implications.

  2. Ideology, affect, semiotics: towards a non-personal theory of personality.

    PubMed

    Larocco, Steve

    2014-06-01

    Personality theories, as Giordano (2014) argues, often treat Western versions of the self as having universal import. Eastern notions of self, however, offer a dramatically different basis for thinking about what personality might be. This paper, nonetheless, seeks to offer a general framework for theorizing about the epiphenomenon of personality in any culture, asserting that it is an effect of specific histories of ideological practices, semiotic networks and systems, and affect, which engage each other in dialogic and dialectical ways. The interactions of these factors, guided by ideology, regularize behavior and affective dynamics, largely in non-personal ways. Subjects are produced and reproduced from these complex interactions, which are situationally specific and simultaneously transpersonal. The subjects formed through these interactions are the basis for the folk psychology of personality, which treats the transient, varying effects of these interactions as more or less reified qualities that form a basis for the construction of selfhood, however conceived.

  3. Theory and applications survey of decentralized control methods

    NASA Technical Reports Server (NTRS)

    Athans, M.

    1975-01-01

    A nonmathematical overview is presented of trends in the general area of decentralized control strategies which are suitable for hierarchical systems. Advances in decentralized system theory are closely related to advances in the so-called stochastic control problem with nonclassical information pattern. The basic assumptions and mathematical tools pertaining to the classical stochastic control problem are outlined. Particular attention is devoted to pitfalls in the mathematical problem formulation for decentralized control. Major conclusions are that any purely deterministic approach to multilevel hierarchical dynamic systems is unlikely to lead to realistic theories or designs, that the flow of measurements and decisions in a decentralized system should not be instantaneous and error-free, and that delays in information exchange in a decentralized system lead to reasonable approaches to decentralized control. A mathematically precise notion of aggregating information is not yet available.

  4. Cognitive and affective components of Theory of Mind in preschoolers with oppositional defiance disorder: Clinical evidence.

    PubMed

    de la Osa, Nuria; Granero, Roser; Domenech, Josep Maria; Shamay-Tsoory, Simone; Ezpeleta, Lourdes

    2016-07-30

    The goal of the study was to examine the affective-cognitive components of Theory of Mind (ToM), in a community sample of 538 preschoolers, and more specifically in a subsample of 40 children diagnosed with ODD. The relationship between affective and cognitive ToM and some ODD clinical characteristics was examined. Children were assessed with structured diagnostic interviews and dimensional measures of psychopathology, impairment and unemotional traits. A measure based on eye-gaze was used to assess ToM. Mixed analysis of variance compared the mean cognitive versus affective scale scores and the between-subjects factor ODD. The association between ToM-scores and clinical measures was assessed through correlation models. Execution and reaction time to emotional and cognitive components of ToM tasks are different at age 5 in normally developing children. Oppositional Defiant children had slower response time when performing the affective mentalizing condition than children without the disorder. The correlation matrix between ToM-scores and clinical measures showed specific associations depending on the impaired ToM aspect and the psychological domain. Results may have clinical implications for the prevention and management of ODD.

  5. Fractionating negative and positive affectivity in handedness: Insights from the Reinforcement Sensitivity Theory of personality.

    PubMed

    Beaton, Alan A; Mutinelli, Sofia; Corr, Philip J

    2016-07-28

    The Annett Hand Preference Questionnaire (AHPQ), as modified by Briggs and Nebes [(1975). Patterns of hand preference in a student population. Cortex, 11(3), 230-238. doi: 10.1016/s0010-9452(75)80005-0 ], was administered to a sample of 177 participants alongside the Reinforcement Sensitivity Theory of Personality Questionnaire [RST-PQ; Corr, P. J., & Cooper, A. (2016). The Reinforcement Sensitivity Theory of Personality Questionnaire (RST-PQ): Development and validation. Psychological Assessment. doi: 10.1037/pas000 ], which measures two factors of defensive negative emotion, motivation and affectivity-the Behavioural Inhibition System (BIS) and the Fight-Flight-Freeze System (FFFS)-and one positive-approach dimension related to reward sensitivity, persistence and reactivity-the Behavioural Approach System. We sought to clarify the nature of negative, and positive, affectivity in relation to handedness. ANOVAs and multiple regression analyses converged on the following conclusions: left-handers were higher on the BIS, not the FFFS, than right-handers; in right-handers only, strength of hand preference was positively correlated with the FFFS, not the BIS. The original assessment method proposed by Annett was also used to assess handedness, but associations with RST-PQ factors were not found. These findings help us to clarify existing issues in the literature and raise new ones for future research.

  6. Leaf microbiota of strawberries as affected by biological control agents.

    PubMed

    Sylla, Justine; Alsanius, Beatrix W; Krüger, Erika; Reineke, Annette; Strohmeier, Stephan; Wohanka, Walter

    2013-10-01

    The increasing use of biological control agents (BCAs) against Botrytis cinerea in strawberry raises the question of whether there are any undesirable impacts of foliar applications of BCAs on nontarget microorganisms in the phyllosphere. Therefore, our objective was to investigate this issue within a field study. Strawberry plants were repeatedly sprayed with three BCAs-namely, RhizoVital 42 fl. (Bacillus amyloliquefaciens FZB42), Trianum-P (Trichoderma harzianum T22), and Naturalis (Beauveria bassiana ATCC 74040)-to suppress Botrytis cinerea infections. Microbial communities of differentially treated leaves were analyzed using plate counts and pyrosequencing and compared with the microbial community of nontreated leaves. Plate count results indicate that the applied Bacillus and Trichoderma spp. survived in the strawberry phyllosphere throughout the strawberry season. However, no significant impacts on the leaf microbiota could be detected by this culture-dependent technique. Pyrosequencing of internal transcribed spacer ribosomal RNA and 16S RNA sequences revealed a change in fungal composition and diversity at class level after the introduction of T. harzianum T22 to the phyllosphere, whereas the bacterial composition and diversity was not affected by either this Trichoderma preparation or the other two BCAs. Our results suggest that pyrosequencing represents a useful method for studying microbial interactions in the phyllosphere.

  7. Glancing and Then Looking: On the Role of Body, Affect, and Meaning in Cognitive Control

    PubMed Central

    Su, Li; Bowman, Howard; Barnard, Philip

    2011-01-01

    In humans, there is a trade-off between the need to respond optimally to the salient environmental stimuli and the need to meet our long-term goals. This implies that a system of salience sensitive control exists, which trades task-directed processing off against monitoring and responding to potentially high salience stimuli that are irrelevant to the current task. Much cognitive control research has attempted to understand these mechanisms using non-affective stimuli. However, recent research has emphasized the importance of emotions, which are a major factor in the prioritization of competing stimuli and in directing attention. While relatively mature theories of cognitive control exist for non-affective settings, exactly how emotions modulate cognitive processes is less well understood. The attentional blink (AB) task is a useful experimental paradigm to reveal the dynamics of both cognitive and affective control in humans. Hence, we have developed the glance–look model, which has replicated a broad profile of data on the semantic AB task and characterized how attentional deployment is modulated by emotion. Taking inspiration from Barnard’s Interacting Cognitive Subsystems, the model relies on a distinction between two levels of meaning: implicational and propositional, which are supported by two corresponding mental subsystems: the glance and the look respectively. In our model, these two subsystems reflect the central engine of cognitive control and executive function. In particular, the interaction within the central engine dynamically establishes a task filter for salient stimuli using a neurobiologically inspired learning mechanism. In addition, the somatic contribution of emotional effects is modeled by a body-state subsystem. We argue that stimulus-driven interaction among these three subsystems governs the movement of control between them. The model also predicts attenuation effects and fringe awareness during the AB. PMID:22194729

  8. AFFECTIVE GUIDANCE OF INTELLIGENT AGENTS: How Emotion Controls Cognition.

    PubMed

    Clore, Gerald L; Palmer, Janet E

    2009-03-01

    Emotions and moods color cognition. In this article, we outline how emotions affect judgments and cognitive performance of human agents. We argue that affective influences are due, not to the affective reactions themselves, but to the information they carry about value, a potentially useful finding for creators of artificial agents. The kind of influence that occurs depends on the focus of the agent at the time. When making evaluative judgments, for example, agents may experience positive affect as a positive attitude toward a person or object. But when an agent focuses on a cognitive task, positive affect may act like performance feedback, with positive affect giving a green light to cognitive, relational processes. By contrast, negative affect tends to inhibit relational processing, resulting in a more perceptual, stimulus-specific processing. One result is that many textbook phenomena from cognitive psychology occur readily in happy moods, but are inhibited in sad moods.

  9. The impact of maternal control on children's anxious cognitions, behaviours and affect: an experimental study.

    PubMed

    Thirlwall, Kerstin; Creswell, Cathy

    2010-10-01

    Controlling parenting is associated with child anxiety however the direction of effects remains unclear. The present study implemented a Latin-square experimental design to assess the impact of parental control on children's anxious affect, cognitions and behaviour. A non-clinical sample of 24 mothers of children aged 4-5 years were trained to engage in (a) controlling and (b) autonomy-granting behaviours in interaction with their child during the preparation of a speech. When mothers engaged in controlling parenting behaviours, children made more negative predictions about their performance prior to delivering their speech and reported feeling less happy about the task, and this was moderated by child trait anxiety. In addition, children with higher trait anxiety displayed a significant increase in observed child anxiety in the controlling condition. The pattern of results was maintained when differences in mothers' levels of negativity and habitual levels of control were accounted for. These findings are consistent with theories that suggest that controlling parenting is a risk factor in the development of childhood anxiety.

  10. Brain and cognitive reserve: Translation via network control theory.

    PubMed

    Medaglia, John Dominic; Pasqualetti, Fabio; Hamilton, Roy H; Thompson-Schill, Sharon L; Bassett, Danielle S

    2017-04-01

    Traditional approaches to understanding the brain's resilience to neuropathology have identified neurophysiological variables, often described as brain or cognitive "reserve," associated with better outcomes. However, mechanisms of function and resilience in large-scale brain networks remain poorly understood. Dynamic network theory may provide a basis for substantive advances in understanding functional resilience in the human brain. In this perspective, we describe recent theoretical approaches from network control theory as a framework for investigating network level mechanisms underlying cognitive function and the dynamics of neuroplasticity in the human brain. We describe the theoretical opportunities offered by the application of network control theory at the level of the human connectome to understand cognitive resilience and inform translational intervention.

  11. Alcohol effects on performance monitoring and adjustment: affect modulation and impairment of evaluative cognitive control.

    PubMed

    Bartholow, Bruce D; Henry, Erika A; Lust, Sarah A; Saults, J Scott; Wood, Phillip K

    2012-02-01

    Alcohol is known to impair self-regulatory control of behavior, though mechanisms for this effect remain unclear. Here, we tested the hypothesis that alcohol's reduction of negative affect (NA) is a key mechanism for such impairment. This hypothesis was tested by measuring the amplitude of the error-related negativity (ERN), a component of the event-related brain potential (ERP) posited to reflect the extent to which behavioral control failures are experienced as distressing, while participants completed a laboratory task requiring self-regulatory control. Alcohol reduced both the ERN and error positivity (Pe) components of the ERP following errors and impaired typical posterror behavioral adjustment. Structural equation modeling indicated that effects of alcohol on both the ERN and posterror adjustment were significantly mediated by reductions in NA. Effects of alcohol on Pe amplitude were unrelated to posterror adjustment, however. These findings indicate a role for affect modulation in understanding alcohol's effects on self-regulatory impairment and more generally support theories linking the ERN with a distress-related response to control failures.

  12. How to fly an aircraft with control theory and splines

    NASA Technical Reports Server (NTRS)

    Karlsson, Anders

    1994-01-01

    When trying to fly an aircraft as smoothly as possible it is a good idea to use the derivatives of the pilot command instead of using the actual control. This idea was implemented with splines and control theory, in a system that tries to model an aircraft. Computer calculations in Matlab show that it is impossible to receive enough smooth control signals by this way. This is due to the fact that the splines not only try to approximate the test function, but also its derivatives. A perfect traction is received but we have to pay in very peaky control signals and accelerations.

  13. Optimization of microstructure development during hot working using control theory

    NASA Astrophysics Data System (ADS)

    Malas, James C.; Frazier, W. Garth; Medina, Enrique A.; Medeiros, Steven; Mullins, W. M.; Chaudhary, Anil; Venugopal, S.; Irwin, R. Dennis; Srinivasan, Raghavan

    1997-09-01

    A new approach for controlling microstructure development during hot working processes is proposed. This approach is based on optimal control theory and involves state-space type models for describing the material behavior and the mechanics of the process. The effect of process control parameters such as strain, strain rate, and temperature on important microstructural features can be systematically formulated and then solved as an optimal control problem. This method has been applied to the optimization of grain size and process parameters such as die geometry and ram velocity during the extrusion of plain carbon steel. Experimental results of this investigation show good agreement with those predicted in the design stage.

  14. Control theory and splines, applied to signature storage

    NASA Technical Reports Server (NTRS)

    Enqvist, Per

    1994-01-01

    In this report the problem we are going to study is the interpolation of a set of points in the plane with the use of control theory. We will discover how different systems generate different kinds of splines, cubic and exponential, and investigate the effect that the different systems have on the tracking problems. Actually we will see that the important parameters will be the two eigenvalues of the control matrix.

  15. Social Control Theory and Delinquency: A Multivariate Test.

    ERIC Educational Resources Information Center

    Wiatrowski, Michael D.; Swatko, Mary K.

    Hirschi's social control theory of delinquency status that delinquency involvement is the function of the failure of an adolescent to form or maintain a bond to society comprised of attachment, commitment, involvement and belief. In the past decade Hirschi and other researchers have found substantial support for this original thesis using tabular…

  16. Integrated control-system design via generalized LQG (GLQG) theory

    NASA Technical Reports Server (NTRS)

    Bernstein, Dennis S.; Hyland, David C.; Richter, Stephen; Haddad, Wassim M.

    1989-01-01

    Thirty years of control systems research has produced an enormous body of theoretical results in feedback synthesis. Yet such results see relatively little practical application, and there remains an unsettling gap between classical single-loop techniques (Nyquist, Bode, root locus, pole placement) and modern multivariable approaches (LQG and H infinity theory). Large scale, complex systems, such as high performance aircraft and flexible space structures, now demand efficient, reliable design of multivariable feedback controllers which optimally tradeoff performance against modeling accuracy, bandwidth, sensor noise, actuator power, and control law complexity. A methodology is described which encompasses numerous practical design constraints within a single unified formulation. The approach, which is based upon coupled systems or modified Riccati and Lyapunov equations, encompasses time-domain linear-quadratic-Gaussian theory and frequency-domain H theory, as well as classical objectives such as gain and phase margin via the Nyquist circle criterion. In addition, this approach encompasses the optimal projection approach to reduced-order controller design. The current status of the overall theory will be reviewed including both continuous-time and discrete-time (sampled-data) formulations.

  17. A gain-control theory of binocular combination.

    PubMed

    Ding, Jian; Sperling, George

    2006-01-24

    In binocular combination, light images on the two retinas are combined to form a single "cyclopean" perceptual image, in contrast to binocular rivalry which occurs when the two eyes have incompatible ("rivalrous") inputs and only one eye;s stimulus is perceived. We propose a computational theory for binocular combination with two basic principles of interaction: in every spatial neighborhood, each eye (i) exerts gain control on the other eye's signal in proportion to the contrast energy of its own input and (ii) additionally exerts gain control on the other eye's gain control. For stimuli of ordinary contrast, when either eye is stimulated alone, the predicted cyclopean image is the same as when both eyes are stimulated equally, coinciding with an easily observed property of natural vision. The gain-control theory is contrast dependent: Very low-contrast stimuli to the left- and right-eye add linearly to form the predicted cyclopean image. The intrinsic nonlinearity manifests itself only as contrast increases. To test the theory more precisely, a horizontal sine wave grating of 0.68 cycles per degree is presented to each eye. The gratings differ in contrast and phase. The predicted (and perceived) cyclopean grating also is a sine wave; its apparent phase indicates the relative contribution of the two eyes to the cyclopean image. For 48 measured combinations of phase and contrast, the theory with only one estimated parameter accounts for 95% of the variance of the data. Therefore, a simple, robust, physiologically plausible gain-control theory accurately describes an early stage of binocular combination.

  18. Making inferences about intention: perceptual control theory as a "theory of mind" for psychologists.

    PubMed

    Marken, Richard S

    2013-08-01

    Theory of Mind (ToM) assumes that humans and possibly other primates understand behavior in terms of inferences about intentions. While there is evidence that primates make such inferences, little attention has been paid to the question of their validity. In order to answer this question it is necessary to know the true intentions underlying behavior. The present paper shows that Perceptual Control Theory can provide a scientific basis for making such determinations using methods derived from control engineering. These methods--called the "Test for the Controlled Variable" (TCV)--are based on the assumption that intentional behavior is equivalent to the process of control. The TCV provides an objective approach to inferring the intentions underlying behavior in terms of the perceptual variables under control and the goal states of those variables. Thus, Perceptual Control Theory represents an empirical ToM for psychologists--one that can be used to understand behavior in terms of inferences about intention that are based on the results of active experimentation rather than passive observation.

  19. Product Distribution Theory for Control of Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Lee, Chia Fan; Wolpert, David H.

    2004-01-01

    Product Distribution (PD) theory is a new framework for controlling Multi-Agent Systems (MAS's). First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint stare of the agents. Accordingly we can consider a team game in which the shared utility is a performance measure of the behavior of the MAS. For such a scenario the game is at equilibrium - the Lagrangian is optimized - when the joint distribution of the agents optimizes the system's expected performance. One common way to find that equilibrium is to have each agent run a reinforcement learning algorithm. Here we investigate the alternative of exploiting PD theory to run gradient descent on the Lagrangian. We present computer experiments validating some of the predictions of PD theory for how best to do that gradient descent. We also demonstrate how PD theory can improve performance even when we are not allowed to rerun the MAS from different initial conditions, a requirement implicit in some previous work.

  20. Unilateral anterior ischemic optic neuropathy: chromatic pupillometry in affected, fellow non-affected and healthy control eyes.

    PubMed

    Herbst, Kristina; Sander, Birgit; Lund-Andersen, Henrik; Wegener, Marianne; Hannibal, Jens; Milea, Dan

    2013-01-01

    The intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin, which is sensitive to blue light. Previous chromatic pupillometry studies have shown that the post-illumination response is considered an indicator of the melanopsin activation. The aim of this study was to investigate the ipRGC mediated pupil response in patients with a unilateral non-arteritic anterior ischemic optic neuropathy (NAION). Consensual pupil responses during and after exposure to continuous 20 s blue (470 nm) or red (660 nm) light of high intensity (300 cd/m(2)) were recorded in each eye for 10 patients. Comparisons were performed both intra-individually (affected versus non-affected eyes) and inter-individually (compared with healthy controls). The pupil response was calculated both during the illumination and during the post-illumination phase. The pupil responses to blue and red colors were significantly reduced in the NAION-affected eyes, compared with the fellow non-affected eyes. When comparing the affected eyes with the healthy control eyes, the post-illumination responses were not significantly different. In addition, the post-illumination pupil responses after blue light exposure were increased in the fellow non-affected patients' eyes, compared with the healthy controls. However, significance was only reached for the late post-illumination response. In conclusion, chromatic pupillometry disclosed reduced post-illumination pupil responses in the NAION-affected eyes, compared with the non-affected fellow eyes, suggesting dysfunction of the ipRGCs. Compared with the responses of the healthy controls, the blue light post-illumination pupil responses were similar in the affected eyes and increased in the fellow non-affected eyes. This suggests a possible adaptive phenomenon, involving the ipRGCs of both eyes after unilateral NAION.

  1. Control theory based airfoil design using the Euler equations

    NASA Technical Reports Server (NTRS)

    Jameson, Antony; Reuther, James

    1994-01-01

    This paper describes the implementation of optimization techniques based on control theory for airfoil design. In our previous work it was shown that control theory could be employed to devise effective optimization procedures for two-dimensional profiles by using the potential flow equation with either a conformal mapping or a general coordinate system. The goal of our present work is to extend the development to treat the Euler equations in two-dimensions by procedures that can readily be generalized to treat complex shapes in three-dimensions. Therefore, we have developed methods which can address airfoil design through either an analytic mapping or an arbitrary grid perturbation method applied to a finite volume discretization of the Euler equations. Here the control law serves to provide computationally inexpensive gradient information to a standard numerical optimization method. Results are presented for both the inverse problem and drag minimization problem.

  2. Coherent control of quantum systems as a resource theory

    NASA Astrophysics Data System (ADS)

    Matera, J. M.; Egloff, D.; Killoran, N.; Plenio, M. B.

    2016-08-01

    Control at the interface between the classical and the quantum world is fundamental in quantum physics. In particular, how classical control is enhanced by coherence effects is an important question both from a theoretical as well as from a technological point of view. In this work, we establish a resource theory describing this setting and explore relations to the theory of coherence, entanglement and information processing. Specifically, for the coherent control of quantum systems, the relevant resources of entanglement and coherence are found to be equivalent and closely related to a measure of discord. The results are then applied to the DQC1 protocol and the precision of the final measurement is expressed in terms of the available resources.

  3. Load theory of selective attention and cognitive control.

    PubMed

    Lavie, Nilli; Hirst, Aleksandra; de Fockert, Jan W; Viding, Essi

    2004-09-01

    A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings suggest 2 selective attention mechanisms: a perceptual selection mechanism serving to reduce distractor perception in situations of high perceptual load that exhaust perceptual capacity in processing relevant stimuli and a cognitive control mechanism that reduces interference from perceived distractors as long as cognitive control functions are available to maintain current priorities (low cognitive load). This theory resolves the long-standing early versus late selection debate and clarifies the role of cognitive control in selective attention.

  4. A theory of diffusion controlled reactions in polyatomic molecule system

    NASA Astrophysics Data System (ADS)

    Kasahara, Kento; Sato, Hirofumi

    2016-11-01

    The conventional Smoluchowski equation has been extensively utilized to investigate diffusion controlled reactions. However, application of the equation is limited to spherical-particle system. In the present study, a new Smoluchowski equation for polyatomic molecular system is derived based on Zwanzig-Mori projection operator method and reference interaction site model (RISM) theory. The theory is applied to monoatomic molecular liquid, and the obtained time-dependent rate constant is virtually identical with that from conventional Smoluchowski equation. For diatomic molecular liquid, time-dependent distribution function and rate constant are obtained, showing a good agreement with those from molecular dynamics simulation.

  5. Acceleration of quantum optimal control theory algorithms with mixing strategies.

    PubMed

    Castro, Alberto; Gross, E K U

    2009-05-01

    We propose the use of mixing strategies to accelerate the convergence of the common iterative algorithms utilized in quantum optimal control theory (QOCT). We show how the nonlinear equations of QOCT can be viewed as a "fixed-point" nonlinear problem. The iterative algorithms for this class of problems may benefit from mixing strategies, as it happens, e.g., in the quest for the ground-state density in Kohn-Sham density-functional theory. We demonstrate, with some numerical examples, how the same mixing schemes utilized in this latter nonlinear problem may significantly accelerate the QOCT iterative procedures.

  6. An application of artificial intelligence theory to reconfigurable flight control

    NASA Technical Reports Server (NTRS)

    Handelman, David A.

    1987-01-01

    Artificial intelligence techniques were used along with statistical hpyothesis testing and modern control theory, to help the pilot cope with the issues of information, knowledge, and capability in the event of a failure. An intelligent flight control system is being developed which utilizes knowledge of cause and effect relationships between all aircraft components. It will screen the information available to the pilots, supplement his knowledge, and most importantly, utilize the remaining flight capability of the aircraft following a failure. The list of failure types the control system will accommodate includes sensor failures, actuator failures, and structural failures.

  7. Comparison of elicitation methods for moral and affective beliefs in the theory of planned behaviour.

    PubMed

    Dean, M; Arvola, A; Vassallo, M; Lähteenmäki, L; Raats, M M; Saba, A; Shepherd, R

    2006-09-01

    Although the theory of planned behaviour (TPB) has been applied successfully in the area of food choice, it has been criticized for its pure utilitarian approach to the factors determining behaviour. Despite the increase in predictive power of the model with added components such as affective attitude and moral and ethical concerns, in most studies the elicitation process still only addresses people's utilitarian beliefs about the behaviour with little attention paid to other aspects. This study compares the traditional method of elicitation of advantages and disadvantages with two other methods (word association and open-ended) in the elicitations of beliefs, attitudes and moral concerns in relation to the consumption of organic foods. Results show the traditional method to be best for eliciting cognitive beliefs, open-ended emotion task for eliciting emotional beliefs and open-ended beliefs task best for moral concerns. The advantages and disadvantages of each method are discussed.

  8. Toward a Theory and Practice for Whole-Person Learning: Reconceptualizing Experience and the Role of Affect.

    ERIC Educational Resources Information Center

    Yorks, Lyle; Kasl, Elizabeth

    2002-01-01

    A pragmatic perspective favors reflective discourse over affect. Heron's theory of personhood takes a phenomenological approach to affective learning. Strategies from this approach can be applied to the phenomenon of learning-within-relationship, in which individuals engage their own whole-person learning and that of others. (Contains 36…

  9. Affiliation and control in marital interaction: interpersonal complementarity is present but is not associated with affect or relationship quality.

    PubMed

    Cundiff, Jenny M; Smith, Timothy W; Butner, Jonathan; Critchfield, Kenneth L; Nealey-Moore, Jill

    2015-01-01

    The principle of complementarity in interpersonal theory states that an actor's behavior tends to "pull, elicit, invite, or evoke" responses from interaction partners who are similar in affiliation (i.e., warmth vs. hostility) and opposite in control (i.e., dominance vs. submissiveness). Furthermore, complementary interactions are proposed to evoke less negative affect and promote greater relationship satisfaction. These predictions were examined in two studies of married couples. Results suggest that complementarity in affiliation describes a robust general pattern of marital interaction, but complementarity in control varies across contexts. Consistent with behavioral models of marital interaction, greater levels of affiliation and lower control by partners-not complementarity in affiliation or control-were associated with less anger and anxiety and greater relationship quality. Partners' levels of affiliation and control combined in ways other than complementarity-mostly additively, but sometimes synergistically-to predict negative affect and relationship satisfaction.

  10. Quantum optimal control theory in the linear response formalism

    SciTech Connect

    Castro, Alberto; Tokatly, I. V.

    2011-09-15

    Quantum optimal control theory (QOCT) aims at finding an external field that drives a quantum system in such a way that optimally achieves some predefined target. In practice, this normally means optimizing the value of some observable, a so-called merit function. In consequence, a key part of the theory is a set of equations, which provides the gradient of the merit function with respect to parameters that control the shape of the driving field. We show that these equations can be straightforwardly derived using the standard linear response theory, only requiring a minor generalization: the unperturbed Hamiltonian is allowed to be time dependent. As a result, the aforementioned gradients are identified with certain response functions. This identification leads to a natural reformulation of QOCT in terms of the Keldysh contour formalism of the quantum many-body theory. In particular, the gradients of the merit function can be calculated using the diagrammatic technique for nonequilibrium Green's functions, which should be helpful in the application of QOCT to computationally difficult many-electron problems.

  11. Intelligent control based on fuzzy logic and neural net theory

    NASA Technical Reports Server (NTRS)

    Lee, Chuen-Chien

    1991-01-01

    In the conception and design of intelligent systems, one promising direction involves the use of fuzzy logic and neural network theory to enhance such systems' capability to learn from experience and adapt to changes in an environment of uncertainty and imprecision. Here, an intelligent control scheme is explored by integrating these multidisciplinary techniques. A self-learning system is proposed as an intelligent controller for dynamical processes, employing a control policy which evolves and improves automatically. One key component of the intelligent system is a fuzzy logic-based system which emulates human decision making behavior. It is shown that the system can solve a fairly difficult control learning problem. Simulation results demonstrate that improved learning performance can be achieved in relation to previously described systems employing bang-bang control. The proposed system is relatively insensitive to variations in the parameters of the system environment.

  12. Comparing the ability of cognitive and affective Theory of Mind in adolescent onset schizophrenia

    PubMed Central

    Li, Dandan; Li, Xiaosi; Yu, Fengqiong; Chen, Xingui; Zhang, Long; Li, Dan; Wei, Qiang; Zhang, Qing; Zhu, Chunyan; Wang, Kai

    2017-01-01

    Background Evidence in the literature suggests that there is an impairment of social cognition in schizophrenia. Theory of Mind (ToM) is defined as one’s ability to understand others’ wishes, beliefs, intentions, and other psychological states and thereby to judge others’ behavior, as an essential component of social cognition. However, there have been limited studies on social cognition, especially ToM in adolescent onset schizophrenia (AOS). The current study aims to investigate ToM abilities in adolescent schizophrenia according to various ToM subcomponents (cognitive ToM and affective ToM) and various ToM orders (first order and second order). Methods This study examines ToM in 35 adolescent schizophrenic patients and 35 healthy adolescents using the “Yoni task” and “Faux Pas Recognition test” to assess their affective and cognitive ToM abilities. Results In the Yoni task, patients with AOS showed differences in ToM abilities either on a different order or under different conditions. The Faux Pas Recognition task results revealed that AOS patients were not always able to recognize a faux pas or understand complicated emotions under the faux pas scenario. Furthermore, as indicated by the correlation analysis, neither cognitive ToM nor affective ToM was related to the patients’ symptoms, disease duration, dose of medication, or intelligence quotient (IQ). Conclusion Our findings showed AOS impairment in the performance of ToM tasks. It seemed that impairment in second-order-ToM is more serious. Moreover, these deficits are largely independent of symptom clusters, disease duration, dose of medication, and IQ. It can be speculated that ToM dysfunction may be a hallmark of adolescent schizophrenia. PMID:28392697

  13. A systems theory approach to career development: Exploring factors that affect science as a career choice

    NASA Astrophysics Data System (ADS)

    Liskey, Brian K.

    This research project was designed to examine the factors that affect students' choice in a career. Specifically, the factors of (a) achievement, (b) interest, (c) self-efficacy, (d) perceived preparation for a career, and (e) being informed about a career will be under investigation. Of key importance to the study is how these factors can affect a student's perception about choosing a science career. A quantitative analysis of secondary data from the 2006 and 2009 Program for International Student Assessment (PISA) international assessment and attitudinal questionnaire provided data on student perceptions and aptitude in science. The sample from PISA included over 400,000 15 year-old students from 57 countries. From the 57 countries, 30 countries, comprised by Organization for Economic and Cooperative Development (OECD), were isolated for analysis. Within this group of 30, 11 were selected for comparison based on their questionnaire response to expectations for a career in science at age 30. The Institute for Educational Science's, International Data Explorer was utilized to acquire and analyze data from the 2006 and 2009 PISA international tests and questionnaires to determine significance between scaled scores and PISA indices. Variables were chosen as factors affecting student's perception on various systems outlined by the Systems Theory of Career Development (Patton & McMahon, 1997) and the Systems Theory of Career Development Framework (Patton & McMahon, 1999). Four country groups were established based on student responses to question 30a from the 2006 PISA attitudinal questionnaire, which asks what career students expected to have at age 30. The results from comparing country groups showed that countries in Group A, which showed the highest values for students expecting a career in science, also had the highest average values for achievement on the PISA science literacy assessment. Likewise, countries that had the lowest values for expecting a career in

  14. Stochastic resonance-a nonlinear control theory interpretation

    NASA Astrophysics Data System (ADS)

    Repperger, D. W.; Farris, K. A.

    2010-07-01

    Stochastic resonance (SR) is an effect that has been known (Benzi, R., Sutera, A., and Vulpiani, A. (1981), 'The Mechanism of Stochastic Resonance', Journal of Physics, A14, L453-L457) for almost three decades and has been extensively studied in biology, statistics, signal processing and in numerous other eclectic areas (Wiesenfeld, K., and Moss, F. (1995), 'Stochastic Resonance and the Benefits of Noise: From Ice Ages to Crayfish and Squids', Nature, 373, 33-36). Herein, a nonlinear control theory analysis is conducted on how to better understand the class of systems that may exhibit the SR effect. Using nonlinear control theory methods, equilibrium points are manipulated to create the SR response (similar to shaping dynamical response in a phase plane). From this approach, a means of synthesising and designing the appropriate class of nonlinear systems is introduced. New types of nonlinear dynamics that demonstrate the SR effects are discovered, which may have utility in control theory as well as in many diverse applications. A numerical simulation illustrates some powerful attributes of these systems.

  15. Searching for pathways involving dressed states in optimal control theory.

    PubMed

    von den Hoff, Philipp; Kowalewski, Markus; de Vivie-Riedle, Regina

    2011-01-01

    Selective population of dressed states has been proposed as an alternative control pathway in molecular reaction dynamics [Wollenhaupt et al., J. Photochem. Photobiol. A: Chem., 2006, 180, 248]. In this article we investigate if, and under which conditions, this strong field pathway is included in the search space of optimal control theory. For our calculations we used the proposed example of the potassium dimer, in which the different target states can be reached via dressed states by resonant transition. Especially, we investigate whether the optimization algorithm is able to find the route involving the dressed states although the target state lies out of resonance in the bare state picture.

  16. Randomized Algorithms for Systems and Control: Theory and Applications

    DTIC Science & Technology

    2008-05-01

    does not display a currently valid OMB control number . 1. REPORT DATE MAY 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4...TITLE AND SUBTITLE Randomized Algorithms for Systems and Control: Theory and Applications 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT... NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) IEIIT-CNR

  17. Factors That Affect Patient Attitudes toward Infection Control Measures.

    ERIC Educational Resources Information Center

    Jones, Daniel J.; And Others

    1991-01-01

    A study investigated patient attitudes toward different disease control measures taken in dental school clinics (n=272 patients) and private practices (n=107 patients). Variables examined included sex, age, educational background, and knowledge of infectious diseases. Patients tended to accept the control measures being used in each context. (MSE)

  18. Using item response theory to investigate the structure of anticipated affect: do self-reports about future affective reactions conform to typical or maximal models?

    PubMed Central

    Zampetakis, Leonidas A.; Lerakis, Manolis; Kafetsios, Konstantinos; Moustakis, Vassilis

    2015-01-01

    In the present research, we used item response theory (IRT) to examine whether effective predictions (anticipated affect) conforms to a typical (i.e., what people usually do) or a maximal behavior process (i.e., what people can do). The former, correspond to non-monotonic ideal point IRT models, whereas the latter correspond to monotonic dominance IRT models. A convenience, cross-sectional student sample (N = 1624) was used. Participants were asked to report on anticipated positive and negative affect around a hypothetical event (emotions surrounding the start of a new business). We carried out analysis comparing graded response model (GRM), a dominance IRT model, against generalized graded unfolding model, an unfolding IRT model. We found that the GRM provided a better fit to the data. Findings suggest that the self-report responses to anticipated affect conform to dominance response process (i.e., maximal behavior). The paper also discusses implications for a growing literature on anticipated affect. PMID:26441806

  19. Small gain stability theory for matched basis function repetitive control

    NASA Astrophysics Data System (ADS)

    Shi, Yunde; Longman, Richard W.; Nagashima, Masaki

    2014-02-01

    Many spacecraft suffer from jitter produced by periodic vibration sources such as momentum wheels, reaction wheels, or control moment gyros. Vibration isolation mounts are needed for fine pointing equipment. Active control methods directly addressing frequencies of interest have the potential to completely cancel the influence of these disturbances. Typical repetitive control methods initially address all frequencies of a given period. Matched basis function repetitive control individually addresses each frequency, finding error components at these frequencies using the projection algorithm, and can converge to zero error, using only frequency response knowledge at addressed frequencies. This results in linear control laws but with periodic coefficients. Frequency domain raising produces a time invariant pole/zero model of the control law. A small gain stability theory is developed, that exhibits very strong stability robustness properties to model error. For convergence to zero tracking error it needs only knowledge of the phase response at addressed frequencies, and it must be known within an accuracy of ±90°. Controllers are then designed by pole-zero placement, bypassing the complexity of original periodic coefficient equations. Compared to the usual repetitive control approaches, the approach here eliminates the need for a robustifying zero phase low pass filter, eliminates the need for interpolation in data, and handles multiple unrelated frequencies easily and naturally.

  20. Serotonin Affects Movement Gain Control in the Spinal Cord

    PubMed Central

    Glaser, Joshua I.; Deng, Linna; Thompson, Christopher K.; Stevenson, Ian H.; Wang, Qining; Hornby, Thomas George; Heckman, Charles J.; Kording, Konrad P.

    2014-01-01

    A fundamental challenge for the nervous system is to encode signals spanning many orders of magnitude with neurons of limited bandwidth. To meet this challenge, perceptual systems use gain control. However, whether the motor system uses an analogous mechanism is essentially unknown. Neuromodulators, such as serotonin, are prime candidates for gain control signals during force production. Serotonergic neurons project diffusely to motor pools, and, therefore, force production by one muscle should change the gain of others. Here we present behavioral and pharmaceutical evidence that serotonin modulates the input–output gain of motoneurons in humans. By selectively changing the efficacy of serotonin with drugs, we systematically modulated the amplitude of spinal reflexes. More importantly, force production in different limbs interacts systematically, as predicted by a spinal gain control mechanism. Psychophysics and pharmacology suggest that the motor system adopts gain control mechanisms, and serotonin is a primary driver for their implementation in force production. PMID:25232107

  1. Anticipatory balance control is affected by loadless training experiences.

    PubMed

    Robert, G; Gueguen, N; Avogadro, P; Mouchnino, L

    2004-09-01

    The main purpose of this study was to identify whether a lot of sports training had any effect on the balance control associated with a leg movement. The nature of the training experience was also an important concern and we chose subject who had undergone specific training experience in absence of equilibrium constraints. To this end a comparison between control (untrained) subjects, triathletes and swimmers was designed to establish whether a general training in sports (triathletes) or a specific loadless training (swimmers), leads to differences in the balance control. A leg movement is preceded by a shift of the center of mass (CM) towards the supporting side to maintain equilibrium and forward to create the condition for progression. To provide an acceleration of the CM sideward and forward, an initial displacement of the center of pressure (CP) towards the moving limb and in posterior direction was performed. Interestingly, the lateral pressure onto the ground was greater increased in swimmers in both leg raising and obstacle avoidance tasks compared to the control group and/or triathletes whereas the backward CP shift in all group was the same. The initial control of the CM shift is very different in swimmers compared to triathletes and controls. The increased lateral pressure onto the ground in swimmers may be a result of a prolonged training in water. This suggests that prolonged training in the absence of equilibrium constraints has more of an effect on balance control than a prolonged general training. In addition, the lack of differences in the backward CP shift suggests that M/L and A/P controls support two functional goals: equilibrium maintenance and movement initiation.

  2. Mortality Salience and Positive Affect Influence Adolescents' Attitudes toward Peers with Physical Disabilities: Terror Management and Broaden and Build Theories

    ERIC Educational Resources Information Center

    Taubman-Ben-Ari, Orit; Eherenfreund-Hager, Ahinoam; Findler, Liora

    2011-01-01

    Attitudes toward teenagers with and without physical disabilities, and their social acceptance, were examined from the perspective of terror management theory and the broaden and build theory. Participants (n = 390, aged 13-17) were divided into 3 experimental conditions: positive emotions, mortality salience, and control. Then, they were shown…

  3. A Theory and Model of Conflict Detection in Air Traffic Control: Incorporating Environmental Constraints

    ERIC Educational Resources Information Center

    Loft, Shayne; Bolland, Scott; Humphreys, Michael S.; Neal, Andrew

    2009-01-01

    A performance theory for conflict detection in air traffic control is presented that specifies how controllers adapt decisions to compensate for environmental constraints. This theory is then used as a framework for a model that can fit controller intervention decisions. The performance theory proposes that controllers apply safety margins to…

  4. Work-family enrichment and job performance: a constructive replication of affective events theory.

    PubMed

    Carlson, Dawn; Kacmar, K Michele; Zivnuska, Suzanne; Ferguson, Merideth; Whitten, Dwayne

    2011-07-01

    Based on affective events theory (AET), we hypothesize a four-step model of the mediating mechanisms of positive mood and job satisfaction in the relationship between work-family enrichment and job performance. We test this model for both directions of enrichment (work-to-family and family-to-work). We used two samples to test the model using structural equation modeling. Results from Study 1, which included 240 full-time employees, were replicated in Study 2, which included 189 matched subordinate-supervisor dyads. For the work-to-family direction, results from both samples support our conceptual model and indicate mediation of the enrichment-performance relationship for the work-to-family direction of enrichment. For the family-to-work direction, results from the first sample support our conceptual model but results from the second sample do not. Our findings help elucidate mixed findings in the enrichment and job performance literatures and contribute to an understanding of the mechanisms linking these concepts. We conclude with a discussion of the practical and theoretical implications of our findings.

  5. The influence of inhibitory processes on affective theory of mind in young and old adults.

    PubMed

    Mahy, Caitlin E V; Vetter, Nora; Kühn-Popp, Nina; Löcher, Carolin; Krautschuk, Susan; Kliegel, Matthias

    2014-01-01

    The primary aim of this study was to examine the impact of an inhibition manipulation on the effect of age on theory of mind (ToM) in an ecologically valid, affective ToM task. Participants were 30 young and 30 old adults. The Cambridge Mindreading Face-Voice Battery was used to measure ToM; in addition, measures of fluid and crystallized intelligence were taken. Participants were subjected to three levels of inhibitory demand during ToM reasoning: emotional inhibition, non-emotional inhibition, and no inhibition. Old adults performed worse than young adults. The emotional and non-emotional inhibition conditions resulted in worse ToM performance compared to the no inhibition condition. There were no differences in the impact of the inhibition conditions on old and young adults. Regression analyses suggested that old adults' crystallized intelligence was a significant predictor of ToM performance, whereas it did not predict young adults' ToM performance. Results are discussed in terms of verbal ability as a possible compensatory mechanism in coping with verbal inhibitory load in ToM reasoning.

  6. Visceral obesity and psychosocial stress: a generalised control theory model

    NASA Astrophysics Data System (ADS)

    Wallace, Rodrick

    2016-07-01

    The linking of control theory and information theory via the Data Rate Theorem and its generalisations allows for construction of necessary conditions statistical models of body mass regulation in the context of interaction with a complex dynamic environment. By focusing on the stress-related induction of central obesity via failure of HPA axis regulation, we explore implications for strategies of prevention and treatment. It rapidly becomes evident that individual-centred biomedical reductionism is an inadequate paradigm. Without mitigation of HPA axis or related dysfunctions arising from social pathologies of power imbalance, economic insecurity, and so on, it is unlikely that permanent changes in visceral obesity for individuals can be maintained without constant therapeutic effort, an expensive - and likely unsustainable - public policy.

  7. Beneficial microbes affect endogenous mechanisms controlling root development

    PubMed Central

    Verbon, Eline H.; Liberman, Louisa M.

    2016-01-01

    Plants have incredible developmental plasticity, enabling them to respond to a wide range of environmental conditions. Among these conditions is the presence of plant growth-promoting rhizobacteria (PGPR) in the soil. Recent studies show that PGPR affect root growth and development within Arabidopsis thaliana root. These effects lead to dramatic changes in root system architecture, that significantly impact aboveground plant growth. Thus, PGPR may promote shoot growth via their effect on root developmental programs. This review focuses on contextualizing root developmental changes elicited by PGPR in light of our understanding of plant-microbe interactions and root developmental biology. PMID:26875056

  8. Does gender affect asthma control in adult asthmatics?

    PubMed

    Dursun, Adile Berna; Kurt, Ozlem Kar; Bayiz, Hulya; Ozkan, Emre; Cakaloglu, Aslihan; Karasoy, Durdu

    2014-05-01

    Several studies have shown gender differences in prevalence of asthma but there is little information about asthma control. In this study, we aimed to evaluate the effect of gender on asthma control in adult asthmatics. Medical records of 242 patients older than 18 years of age who regularly visited the allergy unit were evaluated. Standardized asthma questionnaires like the asthma control test (ACT) were performed. ACT scores, clinical characteristics, and demographic data such as smoking status, education, duration and severity of asthma, atopic status, family history of asthma, analgesic hypersensitivity, number of emergency visits, and hospitalization in the previous year were compared based on gender. In this study, 77.3% of the patients were female. Mean age, body mass index, and duration of asthma were 39.0 ± 0.7, 27.3 ± 0.3, and 6.6 ± 0.4 years, respectively. Of the total, 14.9% of the patients were smokers. Also, 55.8% of them were graduated from middle school, 22.7% from high school, and 14% from university. Atopy rate was 57%. Analgesic hypersensitivity was found in 18.6% of them. There was 30.2% family history of asthma. The asthma severity was mild in 45.5%, moderate in 40.9%, and severe in 13.6% of the patients. One-third of the patients were admitted to emergency room; 1/10th were hospitalized due to asthma in the previous year. ACT scores indicated complete control in 67.8%, partial control in 17.8%, and uncontrolled asthma in 14.5%. Comparing the results of males with females having asthma, there was no statistically significant difference between the two gender according to ACT scores and clinical characteristics. Finally, the results conclude that there was no effect of gender on asthma control assessed with standardized questionnaire in adult asthmatics.

  9. Eye Movements Affect Postural Control in Young and Older Females

    PubMed Central

    Thomas, Neil M.; Bampouras, Theodoros M.; Donovan, Tim; Dewhurst, Susan

    2016-01-01

    Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions. PMID:27695412

  10. Eye Movements Affect Postural Control in Young and Older Females.

    PubMed

    Thomas, Neil M; Bampouras, Theodoros M; Donovan, Tim; Dewhurst, Susan

    2016-01-01

    Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions.

  11. Tumour chemotherapy strategy based on impulse control theory.

    PubMed

    Ren, Hai-Peng; Yang, Yan; Baptista, Murilo S; Grebogi, Celso

    2017-03-06

    Chemotherapy is a widely accepted method for tumour treatment. A medical doctor usually treats patients periodically with an amount of drug according to empirical medicine guides. From the point of view of cybernetics, this procedure is an impulse control system, where the amount and frequency of drug used can be determined analytically using the impulse control theory. In this paper, the stability of a chemotherapy treatment of a tumour is analysed applying the impulse control theory. The globally stable condition for prescription of a periodic oscillatory chemotherapeutic agent is derived. The permanence of the solution of the treatment process is verified using the Lyapunov function and the comparison theorem. Finally, we provide the values for the strength and the time interval that the chemotherapeutic agent needs to be applied such that the proposed impulse chemotherapy can eliminate the tumour cells and preserve the immune cells. The results given in the paper provide an analytical formula to guide medical doctors to choose the theoretical minimum amount of drug to treat the cancer and prevent harming the patients because of over-treating.This article is part of the themed issue 'Horizons of cybernetical physics'.

  12. Combining optimal control theory and molecular dynamics for protein folding.

    PubMed

    Arkun, Yaman; Gur, Mert

    2012-01-01

    A new method to develop low-energy folding routes for proteins is presented. The novel aspect of the proposed approach is the synergistic use of optimal control theory with Molecular Dynamics (MD). In the first step of the method, optimal control theory is employed to compute the force field and the optimal folding trajectory for the Cα atoms of a Coarse-Grained (CG) protein model. The solution of this CG optimization provides an harmonic approximation of the true potential energy surface around the native state. In the next step CG optimization guides the MD simulation by specifying the optimal target positions for the Cα atoms. In turn, MD simulation provides an all-atom conformation whose Cα positions match closely the reference target positions determined by CG optimization. This is accomplished by Targeted Molecular Dynamics (TMD) which uses a bias potential or harmonic restraint in addition to the usual MD potential. Folding is a dynamical process and as such residues make different contacts during the course of folding. Therefore CG optimization has to be reinitialized and repeated over time to accomodate these important changes. At each sampled folding time, the active contacts among the residues are recalculated based on the all-atom conformation obtained from MD. Using the new set of contacts, the CG potential is updated and the CG optimal trajectory for the Cα atoms is recomputed. This is followed by MD. Implementation of this repetitive CG optimization-MD simulation cycle generates the folding trajectory. Simulations on a model protein Villin demonstrate the utility of the method. Since the method is founded on the general tools of optimal control theory and MD without any restrictions, it is widely applicable to other systems. It can be easily implemented with available MD software packages.

  13. Processes Controlling Temporal Changes in Agriculturally-Affected Groundwater

    NASA Astrophysics Data System (ADS)

    Burow, K. R.; Belitz, K.; Jurgens, B. C.

    2014-12-01

    The National Water Quality Assessment (NAWQA) program of the U.S. Geological Survey includes assessment of groundwater-quality changes with time. To better understand changes at a national scale, NAWQA has implemented smaller scale flow-path studies to evaluate the processes affecting these changes. Flow path studies are designed to sample groundwater of different ages. Wells are sampled for a suite of constituents, including tracers of groundwater age. In the 1990s, a 4.6 km transect of monitoring wells was installed near Fresno in the southern Central Valley of California. The region is dominated by intensive agriculture. The wells were sampled in 1994-95, 2003, and 2013 to provide data on changes in water quality and groundwater age. In 2013, the flow path was extended to a regional scale (30 km) by using existing production wells. Preliminary interpretation of the local-scale flow path indicates that nitrate concentrations in the upper 25 m of the aquifer are higher than the USEPA Maximum Contaminant Level (MCL) for drinking water and variably increase or decrease with time. At intermediate depths (25-40 m), nitrate concentrations are lower and show small to moderate increases. The legacy pesticide 1,2-dibromo-3-chloropropane (DBCP) is degrading at a half-life of about 4-6 years. DBCP is present above the MCL at intermediate depths even though it is has been banned from use for more than 30 years. Both nitrate and DBCP appear to be moving vertically downward through the aquifer. Whereas uranium concentrations are generally below the MCL in the local-scale flow path, concentrations increase along the regional transect, with concentrations nearly an order of magnitude above the MCL in some wells. Further evaluation of processes affecting these constituents (such as source, redox, and mobilization factors) will provide important insight that can be applied to other regions and will assist local water managers.

  14. Not that Different in Theory: Discussing the Control-Value Theory of Emotions in Online Learning Environments

    ERIC Educational Resources Information Center

    Daniels, Lia M.; Stupnisky, Robert H.

    2012-01-01

    This commentary investigates the extent to which the control-value theory of emotions (Pekrun, 2006) is applicable in online learning environments. Four empirical studies in this special issue of "The Internet and Higher Education" explicitly used the control-value theory as their theoretical framework and several others have components of the…

  15. Application of nonlinear feedback control theory to supermaneuverable aircraft

    NASA Technical Reports Server (NTRS)

    Garrard, William L.; Enns, Dale F.

    1991-01-01

    Controlled flight at extremely high angles of attack, far exceeding the stall angle, and/or at high angular rates is sometimes referred to as supermaneuvering flight. The objective was to examine methods for design of control laws for aircraft performing supermaneuvers. Since the equations which govern the motion of aircraft during supermaneuvers are nonlinear, this study concentrated on nonlinear control law design procedures. The two nonlinear techniques considered were Nonlinear Quadratic Regulator (NLQR) theory and nonlinear dynamic inversion. A conventional gain scheduled proportional plus integral (P + I) controller was also developed to serve as a baseline design typical of current control laws used in aircraft. A mathematical model of a generic supermaneuverable aircraft was developed from data obtained from the literature. A detailed computer simulation of the aircraft was also developed. This simulation allowed the flying of proposed supermaneuvers and was used to evaluate the performance of the control law designs and to generate linearized models of the aircraft at different flight conditions.

  16. Interactive Image Segmentation Framework Based On Control Theory.

    PubMed

    Zhu, Liangjia; Kolesov, Ivan; Karasev, Peter; Tannenbaum, Allen

    2015-02-21

    Segmentation of anatomical structures in medical imagery is a key step in a variety of clinical applications. Designing a generic, automated method that works for various structures and imaging modalities is a daunting task. Instead of proposing a new specific segmentation algorithm, in this paper, we present a general design principle on how to integrate user interactions from the perspective of control theory. In this formulation, Lyapunov stability analysis is employed to design and analyze an interactive segmentation system. The effectiveness and robustness of the proposed method are demonstrated.

  17. Interactive image segmentation framework based on control theory

    NASA Astrophysics Data System (ADS)

    Zhu, Liangjia; Kolesov, Ivan; Ratner, Vadim; Karasev, Peter; Tannenbaum, Allen

    2015-03-01

    Segmentation of anatomical structures in medical imagery is a key step in a variety of clinical applications. Designing a generic, automated method that works for various structures and imaging modalities is a daunting task. Instead of proposing a new specific segmentation algorithm, in this paper, we present a general design principle on how to integrate user interactions from the perspective of control theory. In this formulation, Lyapunov stability analysis is employed to design an interactive segmentation system. The effectiveness and robustness of the proposed method are demonstrated.

  18. Control of AUVs using differential flatness theory and the derivative-free nonlinear Kalman Filter

    NASA Astrophysics Data System (ADS)

    Rigatos, Gerasimos; Raffo, Guilerme

    2015-12-01

    The paper proposes nonlinear control and filtering for Autonomous Underwater Vessels (AUVs) based on differential flatness theory and on the use of the Derivative-free nonlinear Kalman Filter. First, it is shown that the 6-DOF dynamic model of the AUV is a differentially flat one. This enables its transformation into the linear canonical (Brunovsky) form and facilitates the design of a state feedback controller. A problem that has to be dealt with is the uncertainty about the parameters of the AUV's dynamic model, as well the external perturbations which affect its motion. To cope with this, it is proposed to use a disturbance observer which is based on the Derivative-free nonlinear Kalman Filter. The considered filtering method consists of the standard Kalman Filter recursion applied on the linearized model of the vessel and of an inverse transformation based on differential flatness theory, which enables to obtain estimates of the state variables of the initial nonlinear model of the vessel. The Kalman Filter-based disturbance observer performs simultaneous estimation of the non-measurable state variables of the AUV and of the perturbation terms that affect its dynamics. By estimating such disturbances, their compensation is also succeeded through suitable modification of the feedback control input. The efficiency of the proposed AUV control and estimation scheme is confirmed through simulation experiments.

  19. Integration of a fuel cell into the power system using an optimal controller based on disturbance accommodation control theory

    NASA Astrophysics Data System (ADS)

    Paradkar, Aniruddha; Davari, Asad; Feliachi, Ali; Biswas, Tamal

    In this paper, the integration of a fuel cell into the power system is treated as a load frequency control (LFC) problem with the fuel cell acting as a load disturbance source. The integration of a fuel cell into the power system results into a change in real power. But changes in real power affect the system frequency. Thus, the integration will result into a change of frequency of the synchronous machines. Hence, we need to design a control scheme for keeping the system in the steady state. An optimal controller based on the disturbance accommodation control (DAC) theory is proposed for this load frequency control problem. For demonstrating the effectiveness of the proposed controller, we have considered a two-area power system with the fuel cell introduced in area 1. The fuel cell is considered as an external disturbance to each subsystem. A mathematical model is derived for each subsystem and based upon these models controllers are designed for keeping each subsystem stable, which in turn stabilizes the overall system. So, the proposed controller is decentralized in nature. To account for the modeling uncertainties, an observer is designed to estimate each subsystem's own and interfacing variables. The controller uses these estimates to optimize a given performance index and allocate generating unit outputs according to the requirements.

  20. Exploring New Dimensions of Mathematics-Related Affect: Embodied and Social Theories

    ERIC Educational Resources Information Center

    Hannula, Markku S.

    2012-01-01

    This paper will review theoretical approaches for research on mathematics-related affect from the 1990s until today. In order to organise this field, a metatheory of the affective domain is developed, based on distinctions along three dimensions: 1) cognitive, motivational and emotional aspects of affect; 2) rapidly changing affective states…

  1. Happiness as a motivator: positive affect predicts primary control striving for career and educational goals.

    PubMed

    Haase, Claudia M; Poulin, Michael J; Heckhausen, Jutta

    2012-08-01

    What motivates individuals to invest time and effort and overcome obstacles (i.e., strive for primary control) when pursuing important goals? We propose that positive affect predicts primary control striving for career and educational goals, and we explore the mediating role of control beliefs. In Study 1, positive affect predicted primary control striving for career goals in a two-wave longitudinal study of a U.S. sample. In Study 2, positive affect predicted primary control striving for career and educational goals and objective career outcomes in a six-wave longitudinal study of a German sample. Control beliefs partially mediated the longitudinal associations with primary control striving. Thus, when individuals experience positive affect, they become more motivated to invest time and effort, and overcome obstacles when pursuing their goals, in part because they believe they have more control over attaining their goals.

  2. De-tabooing dying control - a grounded theory study

    PubMed Central

    2013-01-01

    Background Dying is inescapable yet remains a neglected issue in modern health care. The research question in this study was “what is going on in the field of dying today?” What emerged was to eventually present a grounded theory of control of dying focusing specifically on how people react in relation to issues about euthanasia and physician-assisted suicide (PAS). Methods Classic grounded theory was used to analyze interviews with 55 laypersons and health care professionals in North America and Europe, surveys on attitudes to PAS among physicians and the Swedish general public, and scientific literature, North American discussion forum websites, and news sites. Results Open awareness of the nature and timing of a patient’s death became common in health care during the 1960s in the Western world. Open dying awareness contexts can be seen as the start of a weakening of a taboo towards controlled dying called de-tabooing. The growth of the hospice movement and palliative care, but also the legalization of euthanasia and PAS in the Benelux countries, and PAS in Montana, Oregon and Washington further represents de-tabooing dying control. An attitude positioning between the taboo of dying control and a growing taboo against questioning patient autonomy and self-determination called de-paternalizing is another aspect of de-tabooing. When confronted with a taboo, people first react emotionally based on “gut feelings” - emotional positioning. This is followed by reasoning and label wrestling using euphemisms and dysphemisms - reflective positioning. Rarely is de-tabooing unconditional but enabled by stipulated positioning as in soft laws (palliative care guidelines) and hard laws (euthanasia/PAS legislation). From a global perspective three shapes of dying control emerge. First, suboptimal palliative care in closed awareness contexts seen in Asian, Islamic and Latin cultures, called closed dying. Second, palliative care and sedation therapy, but not euthanasia

  3. Quantum optimal control theory applied to transitions in diatomic molecules

    NASA Astrophysics Data System (ADS)

    Lysebo, Marius; Veseth, Leif

    2014-12-01

    Quantum optimal control theory is applied to control electric dipole transitions in a real multilevel system. The specific system studied in the present work is comprised of a multitude of hyperfine levels in the electronic ground state of the OH molecule. Spectroscopic constants are used to obtain accurate energy eigenstates and electric dipole matrix elements. The goal is to calculate the optimal time-dependent electric field that yields a maximum of the transition probability for a specified initial and final state. A further important objective was to study the detailed quantum processes that take place during such a prescribed transition in a multilevel system. Two specific transitions are studied in detail. The computed optimal electric fields as well as the paths taken through the multitude of levels reveal quite interesting quantum phenomena.

  4. Factors Affecting Acceptance & Use of ReWIND: Validating the Extended Unified Theory of Acceptance and Use of Technology

    ERIC Educational Resources Information Center

    Nair, Pradeep Kumar; Ali, Faizan; Leong, Lim Chee

    2015-01-01

    Purpose: This study aims to explain the factors affecting students' acceptance and usage of a lecture capture system (LCS)--ReWIND--in a Malaysian university based on the extended unified theory of acceptance and use of technology (UTAUT2) model. Technological advances have become an important feature of universities' plans to improve the…

  5. Linking Affective Commitment, Career Self-Efficacy, and Outcome Expectations: A Test of Social Cognitive Career Theory

    ERIC Educational Resources Information Center

    Conklin, Amanda M.; Dahling, Jason J.; Garcia, Pablo A.

    2013-01-01

    The authors tested a model based on the satisfaction model of social cognitive career theory (SCCT) that links college students' affective commitment to their major (the emotional identification that students feel toward their area of study) with career decision self-efficacy (CDSE) and career outcome expectations. Results indicate that CDSE…

  6. How aneuploidy affects metabolic control and causes cancer.

    PubMed Central

    Rasnick, D; Duesberg, P H

    1999-01-01

    The complexity and diversity of cancer-specific phenotypes, including de-differentiation, invasiveness, metastasis, abnormal morphology and metabolism, genetic instability and progression to malignancy, have so far eluded explanation by a simple, coherent hypothesis. However, an adaptation of Metabolic Control Analysis supports the 100-year-old hypothesis that aneuploidy, an abnormal number of chromosomes, is the cause of cancer. The results demonstrate the currently counter-intuitive principle that it is the fraction of the genome undergoing differential expression, not the magnitude of the differential expression, that controls phenotypic transformation. Transforming the robust normal phenotype into cancer requires a twofold increase in the expression of thousands of normal gene products. The massive change in gene dose produces highly non-linear (i.e. qualitative) changes in the physiology and metabolism of cells and tissues. Since aneuploidy disrupts the natural balance of mitosis proteins, it also explains the notorious genetic instability of cancer cells as a consequence of the perpetual regrouping of chromosomes. In view of this and the existence of non-cancerous aneuploidy, we propose that cancer is the phenotype of cells above a certain threshold of aneuploidy. This threshold is reached either by the gradual, stepwise increase in the level of aneuploidy as a consequence of the autocatalysed genetic instability of aneuploid cells or by tetraploidization followed by a gradual loss of chromosomes. Thus the initiation step of carcinogenesis produces aneuploidy below the threshold for cancer, and the promotion step increases the level of aneuploidy above this threshold. We conclude that aneuploidy offers a simple and coherent explanation for all the cancer-specific phenotypes. Accordingly, the gross biochemical abnormalities, abnormal cellular size and morphology, the appearance of tumour-associated antigens, the high levels of secreted proteins responsible for

  7. Yeast mutants affecting possible quality control of plasma membrane proteins.

    PubMed

    Li, Y; Kane, T; Tipper, C; Spatrick, P; Jenness, D D

    1999-05-01

    Mutations gef1, stp22, STP26, and STP27 in Saccharomyces cerevisiae were identified as suppressors of the temperature-sensitive alpha-factor receptor (mutation ste2-3) and arginine permease (mutation can1(ts)). These suppressors inhibited the elimination of misfolded receptors (synthesized at 34 degrees C) as well as damaged surface receptors (shifted from 22 to 34 degrees C). The stp22 mutation (allelic to vps23 [M. Babst and S. Emr, personal communication] and the STP26 mutation also caused missorting of carboxypeptidase Y, and ste2-3 was suppressed by mutations vps1, vps8, vps10, and vps28 but not by mutation vps3. In the stp22 mutant, both the mutant and the wild-type receptors (tagged with green fluorescent protein [GFP]) accumulated within an endosome-like compartment and were excluded from the vacuole. GFP-tagged Stp22p also accumulated in this compartment. Upon reaching the vacuole, cytoplasmic domains of both mutant and wild-type receptors appeared within the vacuolar lumen. Stp22p and Gef1p are similar to tumor susceptibility protein TSG101 and voltage-gated chloride channel, respectively. These results identify potential elements of plasma membrane quality control and indicate that cytoplasmic domains of membrane proteins are translocated into the vacuolar lumen.

  8. Sustainable ecosystem management using optimal control theory: part 1 (deterministic systems).

    PubMed

    Shastri, Y; Diwekar, U

    2006-08-07

    The concept of sustainability, an abstract one by its nature, has been given a mathematical representation through the use of Fisher information as a measure. It is used to propose the sustainability hypotheses for dynamical systems, which has paved the way to achieve sustainable development through externally enforced control schemes. For natural systems, this refers to the task of ecosystem management, which is complicated due the lack of clear objectives. This work attempts to incorporate the idea of sustainability in ecosystem management. The natural regulation of ecosystems suggests two possible control options, top-down control and bottom-up control. A comparison of these two control philosophies is made on generic food chain models using the objectives derived from the sustainability hypotheses. Optimal control theory is used to derive the control profiles to handle the complex nature of the models and the objectives. The results indicate a strong relationship between the hypotheses and the dynamic behavior of the models, supporting the use of Fisher information as a measure. As regards to ecosystem management, it has been observed that top-down control is more aggressive but can result in instability, while bottom-up control is guaranteed to give a stable and improved dynamic response. The results also indicate that bottom-up control is a better option to affect shifts in the dynamic regimes of a system, which may be required to recover the system from a natural disaster like the hurricane Katrina.

  9. Affective modulation of the startle reflex and the Reinforcement Sensitivity Theory of personality: The role of sensitivity to reward.

    PubMed

    Aluja, Anton; Blanch, Angel; Blanco, Eduardo; Balada, Ferran

    2015-01-01

    This study evaluated differences in the amplitude of startle reflex and Sensitivity to Reward (SR) and Sensitivity to Punishment (SP) personality variables of the Reinforcement Sensitivity Theory (RST). We hypothesized that subjects with higher scores in SR would obtain a higher startle reflex when exposed to pleasant pictures than lower scores, while higher scores in SP would obtain a higher startle reflex when exposed to unpleasant pictures than subjects with lower scores in this dimension. The sample consisted of 112 healthy female undergraduate psychology students. Personality was assessed using the short version of the Sensitivity to Punishment and Sensitivity Reward Questionnaire (SPSRQ). Laboratory anxiety was controlled by the State Anxiety Inventory. The startle blink reflex was recorded electromyographically (EMG) from the right orbicularis oculi muscle as a response to the International Affective Picture System (IAPS) pleasant, neutral and unpleasant pictures. Subjects higher in SR obtained a significant higher startle reflex response in pleasant pictures than lower scorers (48.48 vs 46.28, p<0.012). Subjects with higher scores in SP showed a light tendency of higher startle responses in unpleasant pictures in a non-parametric local regression graphical analysis (LOESS). The findings shed light on the relationships among the impulsive-disinhibited personality, including sensitivity to reward and emotions evoked through pictures of emotional content.

  10. Ego depletion--is it all in your head? implicit theories about willpower affect self-regulation.

    PubMed

    Job, Veronika; Dweck, Carol S; Walton, Gregory M

    2010-11-01

    Much recent research suggests that willpower--the capacity to exert self-control--is a limited resource that is depleted after exertion. We propose that whether depletion takes place or not depends on a person's belief about whether willpower is a limited resource. Study 1 found that individual differences in lay theories about willpower moderate ego-depletion effects: People who viewed the capacity for self-control as not limited did not show diminished self-control after a depleting experience. Study 2 replicated the effect, manipulating lay theories about willpower. Study 3 addressed questions about the mechanism underlying the effect. Study 4, a longitudinal field study, found that theories about willpower predict change in eating behavior, procrastination, and self-regulated goal striving in depleting circumstances. Taken together, the findings suggest that reduced self-control after a depleting task or during demanding periods may reflect people's beliefs about the availability of willpower rather than true resource depletion.

  11. Using self-determination theory to promote physical activity and weight control: a randomized controlled trial in women.

    PubMed

    Silva, Marlene N; Vieira, Paulo N; Coutinho, Sílvia R; Minderico, Cláudia S; Matos, Margarida G; Sardinha, Luís B; Teixeira, Pedro J

    2010-04-01

    Behavior change interventions are effective to the extent that they affect appropriately-measured outcomes, especially in experimental controlled trials. The primary goal of this study was to analyze the impact of a 1-year weight management intervention based on self-determination theory (SDT) on theory-based psychosocial mediators, physical activity/exercise, and body weight and composition. Participants were 239 women (37.6 +/- 7.1 years; 31.5 +/- 4.1 kg/m(2)) who received either an intervention focused on promoting autonomous forms of exercise regulation and intrinsic motivation, or a general health education program (controls). At 12 months, the intervention group showed increased weight loss (-7.29%,) and higher levels of physical activity/exercise (+138 +/- 26 min/day of moderate plus vigorous exercise; +2,049 +/- 571 steps/day), compared to controls (P < 0.001). Main intervention targets such as more autonomous self-regulation (for treatment and for exercise) and a more autonomous perceived treatment climate revealed large effect sizes (between 0.80 and .96), favoring intervention (P < 0.001). Results suggest that interventions grounded in SDT can be successfully implemented in the context of weight management, enhancing the internalization of more autonomous forms of behavioral regulation, and facilitating exercise adherence, while producing clinically-significant weight reduction, when compared to a control condition. Findings are fully consistent with previous studies conducted within this theoretical framework in other areas of health behavior change.

  12. EDITORIAL: Quantum control theory for coherence and information dynamics Quantum control theory for coherence and information dynamics

    NASA Astrophysics Data System (ADS)

    Viola, Lorenza; Tannor, David

    2011-08-01

    Precisely characterizing and controlling the dynamics of realistic open quantum systems has emerged in recent years as a key challenge across contemporary quantum sciences and technologies, with implications ranging from physics, chemistry and applied mathematics to quantum information processing (QIP) and quantum engineering. Quantum control theory aims to provide both a general dynamical-system framework and a constructive toolbox to meet this challenge. The purpose of this special issue of Journal of Physics B: Atomic, Molecular and Optical Physics is to present a state-of-the-art account of recent advances and current trends in the field, as reflected in two international meetings that were held on the subject over the last summer and which motivated in part the compilation of this volume—the Topical Group: Frontiers in Open Quantum Systems and Quantum Control Theory, held at the Institute for Theoretical Atomic, Molecular and Optical Physics (ITAMP) in Cambridge, Massachusetts (USA), from 1-14 August 2010, and the Safed Workshop on Quantum Decoherence and Thermodynamics Control, held in Safed (Israel), from 22-27 August 2010. Initial developments in quantum control theory date back to (at least) the early 1980s, and have been largely inspired by the well-established mathematical framework for classical dynamical systems. As the above-mentioned meetings made clear, and as the burgeoning body of literature on the subject testifies, quantum control has grown since then well beyond its original boundaries, and has by now evolved into a highly cross-disciplinary field which, while still fast-moving, is also entering a new phase of maturity, sophistication, and integration. Two trends deserve special attention: on the one hand, a growing emphasis on control tasks and methodologies that are specifically motivated by QIP, in addition and in parallel to applications in more traditional areas where quantum coherence is nevertheless vital (such as, for instance

  13. In the mood to get over yourself: mood affects theory-of-mind use.

    PubMed

    Converse, Benjamin A; Lin, Shuhong; Keysar, Boaz; Epley, Nicholas

    2008-10-01

    Understanding others' behavior often involves attributing mental states to them by using one's "theory of mind." We argue that using theory of mind to recognize differences between one's own perspective and another's perspective is a deliberate process of inference that may be influenced by incidental mood. Because sadness is associated with more systematic and deliberate processing whereas happiness is associated with more heuristic processing, we predicted that theory-of-mind use would be facilitated by sadness compared with happiness. Two experiments supported this prediction, demonstrating that participants were more likely to utilize knowledge about others to make inferences about their mental states when they were induced to feel sad than when they were induced to feel happy. These results provide both theoretical insight into the psychological mechanisms that govern theory of mind as well as practical insight into a common source of variability in its use.

  14. Integrating attentional control theory and the strength model of self-control.

    PubMed

    Englert, Chris; Bertrams, Alex

    2015-01-01

    In the present article, we argue that it may be fruitful to incorporate the ideas of the strength model of self-control into the core assumptions of the well-established attentional control theory (ACT). In ACT, it is assumed that anxiety automatically leads to attention disruption and increased distractibility, which may impair subsequent cognitive or perceptual-motor performance, but only if individuals do not have the ability to counteract this attention disruption. However, ACT does not clarify which process determines whether one can volitionally regulate attention despite experiencing high levels of anxiety. In terms of the strength model of self-control, attention regulation can be viewed as a self-control act depending on the momentary availability of self-control strength. We review literature that has revealed that self-control strength moderates the anxiety-performance relationship, discuss how to integrate these two theoretical models, and offer practical recommendations of how to counteract negative anxiety effects.

  15. Optimal control of ICU patient discharge: from theory to implementation.

    PubMed

    Mallor, Fermín; Azcárate, Cristina; Barado, Julio

    2015-09-01

    This paper deals with the management of scarce health care resources. We consider a control problem in which the objective is to minimize the rate of patient rejection due to service saturation. The scope of decisions is limited, in terms both of the amount of resources to be used, which are supposed to be fixed, and of the patient arrival pattern, which is assumed to be uncontrollable. This means that the only potential areas of control are speed or completeness of service. By means of queuing theory and optimization techniques, we provide a theoretical solution expressed in terms of service rates. In order to make this theoretical analysis useful for the effective control of the healthcare system, however, further steps in the analysis of the solution are required: physicians need flexible and medically-meaningful operative rules for shortening patient length of service to the degree needed to give the service rates dictated by the theoretical analysis. The main contribution of this paper is to discuss how the theoretical solutions can be transformed into effective management rules to guide doctors' decisions. The study examines three types of rules based on intuitive interpretations of the theoretical solution. Rules are evaluated through implementation in a simulation model. We compare the service rates provided by the different policies with those dictated by the theoretical solution. Probabilistic analysis is also included to support rule validity. An Intensive Care Unit is used to illustrate this control problem. The study focuses on the Markovian case before moving on to consider more realistic LoS distributions (Weibull, Lognormal and Phase-type distribution).

  16. External control of the GAL network in S. cerevisiae: a view from control theory.

    PubMed

    Yang, Ruoting; Lenaghan, Scott C; Wikswo, John P; Zhang, Mingjun

    2011-04-29

    While there is a vast literature on the control systems that cells utilize to regulate their own state, there is little published work on the formal application of control theory to the external regulation of cellular functions. This paper chooses the GAL network in S. cerevisiae as a well understood benchmark example to demonstrate how control theory can be employed to regulate intracellular mRNA levels via extracellular galactose. Based on a mathematical model reduced from the GAL network, we have demonstrated that a galactose dose necessary to drive and maintain the desired GAL genes' mRNA levels can be calculated in an analytic form. And thus, a proportional feedback control can be designed to precisely regulate the level of mRNA. The benefits of the proposed feedback control are extensively investigated in terms of stability and parameter sensitivity. This paper demonstrates that feedback control can both significantly accelerate the process to precisely regulate mRNA levels and enhance the robustness of the overall cellular control system.

  17. Affective science perspectives on cancer control: strategically crafting a mutually beneficial research agenda.

    PubMed

    Ferrer, Rebecca A; Green, Paige A; Barrett, Lisa Feldman

    2015-05-01

    Cancer control research involves the conduct of basic and applied behavioral and social sciences to reduce cancer incidence, morbidity, and mortality and improve quality of life. Given the importance of behavior in cancer control, fundamental research is necessary to identify psychological mechanisms underlying cancer risk, prevention, and management behaviors. Cancer prevention, diagnosis, and treatment are often emotionally laden. As such, affective science research to elucidate questions related to the basic phenomenological nature of emotion, stress, and mood is necessary to understand how cancer control can be hindered or facilitated by emotional experiences. To date, the intersection of basic affective science research and cancer control remains largely unexplored. The goal of this article is to outline key questions in the cancer control research domain that provide an ecologically valid context for new affective science discoveries. We also provide examples of ways in which basic affective discoveries could inform future cancer prevention and control research. These examples are not meant to be exhaustive or prescriptive but instead are offered to generate creative thought about the promise of a cancer research context for answering basic affective science questions. Together, these examples provide a compelling argument for fostering collaborations between affective and cancer control scientists.

  18. Affective science perspectives on cancer control: Strategically crafting a mutually beneficial research agenda

    PubMed Central

    Ferrer, Rebecca A.; McDonald, Paige Green; Barrett, Lisa Feldman

    2015-01-01

    Cancer control research involves the conduct of basic and applied behavioral and social sciences to reduce cancer incidence, morbidity, and mortality, and improve quality of life. Given the importance of behavior in cancer control, fundamental research is necessary to identify psychological mechanisms underlying cancer risk, prevention, and management behaviors. Cancer prevention, diagnosis, and treatment are often emotionally-laden. As such, affective science research to elucidate questions related to basic phenomenological nature of emotion, stress, and mood is necessary to understand how cancer control can be hindered or facilitated by emotional experiences. To date, the intersection of basic affective science research and cancer control remains largely unexplored. The goal of this paper is to outline key questions in the cancer control research domain that provide an ecologically valid context for new affective science discoveries. We also provide examples of ways in which basic affective discoveries could inform future cancer prevention and control research. These examples are not meant to be exhaustive or prescriptive, but instead are offered to generate creative thought about the promise of a cancer research context for answering basic affective science questions. Together, these examples provide a compelling argument for fostering collaborations between affective and cancer control scientists. PMID:25987511

  19. Understanding controlled drug release from mesoporous silicates: theory and experiment.

    PubMed

    Ukmar, T; Maver, U; Planinšek, O; Kaučič, V; Gaberšček, M; Godec, A

    2011-11-07

    Based on the results of carefully designed experiments upgraded with appropriate theoretical modeling, we present clear evidence that the release curves from mesoporous materials are significantly affected by drug-matrix interactions. In experimental curves, these interactions are manifested as a non-convergence at long times and an inverse dependence of release kinetics on pore size. Neither of these phenomena is expected in non-interacting systems. Although both phenomena have, rather sporadically, been observed in previous research, they have not been explained in terms of a general and consistent theoretical model. The concept is demonstrated on a model drug indomethacin embedded into SBA-15 and MCM-41 porous silicates. The experimental release curves agree exceptionally well with theoretical predictions in the case of significant drug-wall attractions. The latter are described using a 2D Fokker-Planck equation. One could say that the interactions affect the relative cross-section of pores where the local flux has a non-vanishing axial component and in turn control the effective transfer of drug into bulk solution. Finally, we identify the critical parameters determining the pore size dependence of release kinetics and construct a dynamic phase diagram of the various resulting transport regimes.

  20. SimSup's Loop: A Control Theory Approach to Spacecraft Operator Training

    NASA Technical Reports Server (NTRS)

    Owens, Brandon Dewain; Crocker, Alan R.

    2015-01-01

    Immersive simulation is a staple of training for many complex system operators, including astronauts and ground operators of spacecraft. However, while much has been written about simulators, simulation facilities, and operator certification programs, the topic of how one develops simulation scenarios to train a spacecraft operator is relatively understated in the literature. In this paper, an approach is presented for using control theory as the basis for developing the immersive simulation scenarios for a spacecraft operator training program. The operator is effectively modeled as a high level controller of lower level hardware and software control loops that affect a select set of system state variables. Simulation scenarios are derived from a STAMP-based hazard analysis of the operator's high and low level control loops. The immersive simulation aspect of the overall training program is characterized by selecting a set of scenarios that expose the operator to the various inadequate control actions that stem from control flaws and inadequate control executions in the different sections of the typical control loop. Results from the application of this approach to the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission are provided through an analysis of the simulation scenarios used for operator training and the actual anomalies that occurred during the mission. The simulation scenarios and inflight anomalies are mapped to specific control flaws and inadequate control executions in the different sections of the typical control loop to illustrate the characteristics of anomalies arising from the different sections of the typical control loop (and why it is important for operators to have exposure to these characteristics). Additionally, similarities between the simulation scenarios and inflight anomalies are highlighted to make the case that the simulation scenarios prepared the operators for the mission.

  1. Interactive effects of trait and state affect on top-down control of attention.

    PubMed

    Hur, Juyoen; Miller, Gregory A; McDavitt, Jenika R B; Spielberg, Jeffrey M; Crocker, Laura D; Infantolino, Zachary P; Towers, David N; Warren, Stacie L; Heller, Wendy

    2015-08-01

    Few studies have investigated how attentional control is affected by transient affective states while taking individual differences in affective traits into consideration. In this study, participants completed a color-word Stroop task immediately after undergoing a positive, neutral or negative affective context manipulation (ACM). Behavioral performance was unaffected by any ACM considered in isolation. For individuals high in trait negative affect (NA), performance was impaired by the negative but not the positive or neutral ACM. Neuroimaging results indicate that activity in primarily top-down control regions of the brain (inferior frontal gyrus and dorsal anterior cingulate cortex) was suppressed in the presence of emotional arousal (both negative and positive ACMs). This effect appears to have been exacerbated or offset by co-occurring activity in other top-down control regions (parietal) and emotion processing regions (orbitofrontal cortex, amygdala and nucleus accumbens) as a function of the valence of state affect (positive or negative) and trait affect (trait NA or trait PA). Neuroimaging results are consistent with behavioral findings. In combination, they indicate both additive and interactive influences of trait and state affect on top-down control of attention.

  2. Control of quadrotors using differential flatness theory and the derivative-free nonlinear Kalman filter

    NASA Astrophysics Data System (ADS)

    Rigatos, Gerasimos; Siano, Pierluigi

    2013-10-01

    Using differential flatness theory it is shown that the model of a quadropter can be transformed to linear canonical form. For the linearized equivalent of the quadropter it is shown that a state feedback controller can be designed. Since certain elements of the state vector of the linearized system can not be measured directly, it is proposed to estimate them with the use of a novel filtering method, the so-called Derivative-free nonlinear Kalman Filter. Moreover, by redesigning the Kalman Filter as a disturbance observer, it is is shown that one can estimate simultaneously external disturbances terms that affect the quadropter or disturbance terms which are associated with parametric uncertainty. The efficiency of the proposed control scheme is checked through simulation experiments.

  3. Affective Qualities of Sibling Disputes, Mothers' Conflict Attitudes, and Children's Theory of Mind Development

    ERIC Educational Resources Information Center

    Randell, Angela C.; Peterson, Candida C.

    2009-01-01

    Preschoolers' theory of mind (ToM) was examined in relation to emotional features of their conflicts with siblings, using mothers as privileged informants. Fifty-four children aged 3 to 5 years and their 54 mothers took part. Children were given 10 standard false belief tasks and a standardized language test. Mothers completed questionnaires,…

  4. Spiking Phineas Gage: A Neurocomputational Theory of Cognitive-Affective Integration in Decision Making

    ERIC Educational Resources Information Center

    Wagar, Brandon M.; Thagard, Paul

    2004-01-01

    The authors present a neurological theory of how cognitive information and emotional information are integrated in the nucleus accumbens during effective decision making. They describe how the nucleus accumbens acts as a gateway to integrate cognitive information from the ventromedial prefrontal cortex and the hippocampus with emotional…

  5. Application of Multivariable Control Theory to Aircraft Control Laws. Final Report: Multivariable Control Design Guidelines.

    DTIC Science & Technology

    1996-05-01

    theorem from mathematical systems theory called the small-gain theorem [ Desoer 1975]. This theorem applies to general feedback loops of the form shown in...S. Boyd, "Branch and Bound Methodology for Matrix Poly- 255 tope Stability Problems," IEEE CDC, Honolulu, 1990. [ Desoer 1975] Desoer , C. A

  6. Stabilization of ultracold molecules using optimal control theory

    SciTech Connect

    Koch, Christiane P.; Palao, Jose P.; Kosloff, Ronnie; Masnou-Seeuws, Francoise

    2004-07-01

    In recent experiments on ultracold matter, molecules have been produced from ultracold atoms by photoassociation, Feshbach resonances, and three-body recombination. The created molecules are translationally cold, but vibrationally highly excited. This will eventually lead them to be lost from the trap due to collisions. We propose shaped laser pulses to transfer these highly excited molecules to their ground vibrational level. Optimal control theory is employed to find the light field that will carry out this task with minimum intensity. We present results for the sodium dimer. The final target can be reached to within 99% provided the initial guess field is physically motivated. We find that the optimal fields contain the transition frequencies required by a good Franck-Condon pumping scheme. The analysis identifies the ranges of intensity and pulse duration which are able to achieve this task before any other competing processes take place. Such a scheme could produce stable ultracold molecular samples or even stable molecular Bose-Einstein condensates.

  7. Interface controlled plastic flow modelled by strain gradient plasticity theory

    NASA Astrophysics Data System (ADS)

    Pardoen, Thomas; Massart, Thierry J.

    The resistance to plastic flow in metals is often dominated by the presence of interfaces which interfere with dislocation nucleation and motion. Interfaces can be static such as grain and phase boundaries or dynamic such as new boundaries resulting from a phase transformation. The interface can be hard and fully impenetrable to dislocations, or soft and partly or fully transparent. The interactions between dislocations and interfaces constitute the main mechanism controlling the strength and strain hardening capacity of many metallic systems especially in very fine microstructures with a high density of interfaces. A phenomenological strain gradient plasticity theory is used to introduce, within a continuum framework, higher order boundary conditions which empirically represent the effect of interfaces on plastic flow. The strength of the interfaces can evolve during the loading in order to enrich the description of their response. The behaviour of single and dual phase steels, with possible TRIP effect, accounting for the interactions with static and dynamic boundaries, is addressed, with a specific focus on the size dependent strength and ductility balance. The size dependent response of weak precipitate free zones surrounding grain boundaries is treated as an example involving more than one microstructural length scale.

  8. The theory of "truth": how counterindustry campaigns affect smoking behavior among teens.

    PubMed

    Hershey, James C; Niederdeppe, Jeff; Evans, W Douglas; Nonnemaker, James; Blahut, Steven; Holden, Debra; Messeri, Peter; Haviland, M Lyndon

    2005-01-01

    This study used structural equation modeling to test a theory-based model of the pathways by which exposure to the "truth" counterindustry media campaign influenced beliefs, attitudes, and smoking behavior in national random-digit-dial telephone surveys of 16,000 12- to 17-year-olds before, 8 months after, and 15 months after campaign launch. Consistent with concepts from the theory of reasoned action, youth in markets with higher levels of campaign exposure had more negative beliefs about tobacco industry practices and more negative attitudes toward the tobacco industry. Models also provided support for a social inoculation effect, because negative industry attitudes were associated with lower receptivity to protobacco advertising and with less progression along a continuum of smoking intentions and behavior.

  9. A Theory for Market Impact: How Order Flow Affects Stock Price

    NASA Astrophysics Data System (ADS)

    Gerig, Austin

    2008-04-01

    It is known that the impact of transactions on stock price (market impact) is a concave function of the size of the order, but there exists little quantitative theory that suggests why this is so. I develop a quantitative theory for the market impact of hidden orders (orders that reflect the true intention of buying and selling) that matches the empirically measured result and that reproduces some of the non-trivial and universal properties of stock returns (returns are percent changes in stock price). The theory is based on a simple premise, that the stock market can be modeled in a mechanical way - as a device that translates order flow into an uncorrelated price stream. Given that order flow is highly autocorrelated, this premise requires that market impact (1) depends on past order flow and (2) is asymmetric for buying and selling. I derive the specific form for the dependence in (1) by assuming that current liquidity responds to information about all currently active hidden orders (liquidity is a measure of the price response to a transaction of a given size). This produces an equation that suggests market impact should scale logarithmically with total order size. Using data from the London Stock Exchange I empirically measure market impact and show that the result matches the theory. Also using empirical data, I qualitatively specify the asymmetry of (2). Putting all results together, I form a model for market impact that reproduces three universal properties of stock returns - that returns are uncorrelated, that returns are distributed with a power law tail, and that the magnitude of returns is highly autocorrelated (also known as clustered volatility).

  10. Local control theory using trajectory surface hopping and linear-response time-dependent density functional theory.

    PubMed

    Curchod, Basile F E; Penfold, Thomas J; Rothlisberger, Ursula; Tavernelli, Ivano

    2013-01-01

    The implementation of local control theory using nonadiabatic molecular dynamics within the framework of linear-response time-dependent density functional theory is discussed. The method is applied to study the photoexcitation of lithium fluoride, for which we demonstrate that this approach can efficiently generate a pulse, on-the-fly, able to control the population transfer between two selected electronic states. Analysis of the computed control pulse yields insights into the photophysics of the process identifying the relevant frequencies associated to the curvature of the initial and final state potential energy curves and their energy differences. The limitations inherent to the use of the trajectory surface hopping approach are also discussed.

  11. Implicit theories about willpower predict the activation of a rest goal following self-control exertion.

    PubMed

    Job, Veronika; Bernecker, Katharina; Miketta, Stefanie; Friese, Malte

    2015-10-01

    Past research indicates that peoples' implicit theories about the nature of willpower moderate the ego-depletion effect. Only people who believe or were led to believe that willpower is a limited resource (limited-resource theory) showed lower self-control performance after an initial demanding task. As of yet, the underlying processes explaining this moderating effect by theories about willpower remain unknown. Here, we propose that the exertion of self-control activates the goal to preserve and replenish mental resources (rest goal) in people with a limited-resource theory. Five studies tested this hypothesis. In Study 1, individual differences in implicit theories about willpower predicted increased accessibility of a rest goal after self-control exertion. Furthermore, measured (Study 2) and manipulated (Study 3) willpower theories predicted an increased preference for rest-conducive objects. Finally, Studies 4 and 5 provide evidence that theories about willpower predict actual resting behavior: In Study 4, participants who held a limited-resource theory took a longer break following self-control exertion than participants with a nonlimited-resource theory. Longer resting time predicted decreased rest goal accessibility afterward. In Study 5, participants with an induced limited-resource theory sat longer on chairs in an ostensible product-testing task when they had engaged in a task requiring self-control beforehand. This research provides consistent support for a motivational shift toward rest after self-control exertion in people holding a limited-resource theory about willpower.

  12. Opposite effect of conflict context modulation on neural mechanisms of cognitive and affective control.

    PubMed

    Chen, Taolin; Kendrick, Keith Maurice; Feng, Chunliang; Yang, Suyong; Wang, Xiaogang; Yang, Xun; Lei, Du; Wu, Min; Huang, Xiaoqi; Gong, Qiyong; Luo, Yuejia

    2014-05-01

    This study investigated the neural effect of conflict context modulation of cognitive and affective conflict processing by recording evoked-response potentials in cognitive and affective versions of a flanker task. By varying the proportion of congruent and incongruent trials in a block, we found different patterns of the context effect on evoked potentials during cognitive and affective conflict processing. For posterior N1 amplitude, frequent incongruent trials produced a larger effect only in the affective task. The opposite pattern of the context effect was observed for the central N450, which was enhanced by frequent cognitive but reduced by frequent affective contexts. We found similar context effect on the parietal sustained potential in both tasks. Overall, our findings suggest that cognitive and affective conflict processing engage a context-dependent attentional control mechanism but a common conflict response system.

  13. [Social institutions and tempering of affects as "contraints" of social change. Norbert Elias' theory on the civilization theory in light of the biologic system theory of evolution].

    PubMed

    Weinich, Detlef

    2005-01-01

    This study is to be regarded as a contribution to interdisciplinary research and represents an attempt to clarify the question of whether and to what extent concepts that have been developed in the field of theoretical biology and which have a high degree of importance here can also be applied to sociological phenomena. In particular it is intended to examine the question of whether the civilizing process can be adequately treated using the evolutionary concept of "Constraints". This term, which has only recently been introduced into the discussion by PERE ALBERCH as an evolutionary factor, comprises all of the internal factors which influence the further course of the evolution of a system by ruling out certain possibilities, thus showing a limiting effect. Although "Constraints" go beyond the scope of Darwinian teachings about selection by the environment, they are increasingly accepted today as evolution factors by well-known exponents of Darwinian theory (cf. MAYNARD-SMITH 1985). The increase in popularity of "constraints" is also an expression of the rediscovery of a phenomenon which was originally expressed by RUPERT RIEDL and was introduced by him into German literature in the seventies. In the clarification of this question, special reference is made to the "theory of the civilizing process" by NORBERT ELIAS, since here a highly respected scholar has presented an important sociological theory. Moreover, there is such good scientific access to ELIAS because this author exemplifies his theses in historical terms and thus to a certain extent makes his explanations verifiable in scientific terms. In the treatment of this topic, the central terms and theses of ELIAS will be presented from the considerable scope of his work, and then illustrated with the help of several selected historical case studies. Furthermore, reference will be made at the relevant points to parallels and analogies which the works of ELIAS have to other, predominantly system

  14. O the Use of Modern Control Theory for Active Structural Acoustic Control.

    NASA Astrophysics Data System (ADS)

    Saunders, William Richard

    A modern control theory formulation of Active Structural Acoustic Control (ASAC) of simple structures radiating acoustic energy into light or heavy fluid mediums is discussed in this dissertation. ASAC of a baffled, simply-supported plate subject to mechanical disturbances is investigated. For the case of light fluid loading, a finite element modelling approach is used to extend previous ASAC design methods. Vibration and acoustic controllers are designed for the plate. Comparison of the controller performance shows distinct advantages of the ASAC method for minimizing radiated acoustic power. A novel approach to the modelling of the heavy fluid-loaded plate is developed here. Augmenting structural and acoustic dynamics using state vector formalism allows the design of both vibration and ASAC controllers for the fluid-loaded plate. This modern control approach to active structural acoustic control is unique in its ability to suppress both persistent and transient disturbances on a plate in a heavy fluid. Numerical simulations of the open-loop and closed-loop plate response are provided to support the theoretical developments.

  15. Toddler Inhibitory Control, Bold Response to Novelty, and Positive Affect Predict Externalizing Symptoms in Kindergarten

    PubMed Central

    Buss, Kristin A.; Kiel, Elizabeth J.; Morales, Santiago; Robinson, Emily

    2013-01-01

    Poor inhibitory control and bold-approach have been found to predict the development of externalizing behavior problems in young children. Less research has examined how positive affect may influence the development of externalizing behavior in the context of low inhibitory control and high approach. We used a multimethod approach to examine how observed toddler inhibitory control, bold-approach, and positive affect predicted externalizing outcomes (observed, adult- and self-reported) in additive and interactive ways at the beginning of kindergarten. 24-month-olds (N = 110) participated in a laboratory visit and 84 were followed up in kindergarten for externalizing behaviors. Overall, children who were low in inhibitory control, high in bold-approach, and low in positive affect at 24-months of age were at greater risk for externalizing behaviors during kindergarten. PMID:25018589

  16. Negative Affectivity and Effortful Control in Mothers With Borderline Personality Disorder and in Their Young Children.

    PubMed

    Mena, Christina G; Macfie, Jenny; Strimpfel, Jennifer M

    2016-07-07

    Research has examined temperament in individuals with borderline personality disorder (BPD) but not in their offspring, despite offspring's risk of developing BPD and the importance of temperament in the etiology of BPD. We recruited a low-socioeconomic sample of 36 mothers with BPD and their children ages 4 through 7, and 34 normative comparisons. Replicating prior studies, mothers with BPD reported themselves as having more negative affectivity (frustration, fear) and less effortful control (inhibitory control, attentional control, activation control) than did comparisons. Mothers with BPD also reported that their offspring had more negative affectivity (anger/frustration, fear) and less effortful control (inhibitory control, attentional focusing) than did comparisons. We were concerned about potential bias and shared method variance. We therefore provided validity support for mothers' ratings of their children with teacher ratings of child behavior and child self-report via their story-stem completion narratives. We discuss children's temperamental vulnerability versus differential susceptibility to the environment.

  17. Locus of Control and Academic Achievement: Integrating Social Learning Theory and Expectancy-Value Theory

    ERIC Educational Resources Information Center

    Youse, Keith Edward

    2012-01-01

    The current study examines predictors of math achievement and college graduation by integrating social learning theory and expectancy-value theory. Data came from a nationally-representative longitudinal database tracking 12,144 students over twelve years from 8th grade forward. Models for math achievement and college graduation were tested…

  18. Neuroathesetics and growing interest in "positive affect" in psychiatry: new evidence and prospects for the theory of informational needs.

    PubMed

    Branković, Saša

    2013-06-01

    What are the necessary and sufficient conditions to experience pleasure in interpersonal communication and dealing with art, science, and philosophy - this is what the theory of informational needs (TIN) suggested eleven years ago is about. At the same time, at the beginning of this century, several lines of research have emerged. Neuroaesthetics has been established; the discovery of the mirror neuron system and theories about its function have appeared; a growing interest in positive affect and pleasure has developed in psychiatry and medicine. The purpose of the present paper is to reconsider the TIN (Branković 2001) in the context of the advance in neuroscience during the last decade and to show how much conceptual clarity is gained when the recent empirical and theoretical findings are viewed from the standpoint of the TIN. A computational model of the aesthetic response based on the TIN's two-factor model of hedonic value of stimuli is delineated.

  19. Neurologizing the Psychology of Affects: How Appraisal-Based Constructivism and Basic Emotion Theory Can Coexist.

    PubMed

    Panksepp, Jaak

    2007-09-01

    Abundant neurobehavioral data, not discussed by Lisa Feldman Barrett (2006), support the existence of a variety of core emotional operating systems in ancient subneocortical regions of the brain (Panksepp, 1998a, 2005a). Such brain systems are the primary-process ancestral birthrights of all mammals. There may be as many genetically and neurochemically coded subcortical affect systems in emotionally rich medial regions of the brain as there are "natural" emotional action systems in the brain. When emotional primes are aroused directly, as with local electrical or chemical stimulation, the affective changes sustain conditioned place preferences and place aversions, which are the premier secondary-process indices of affective states in animals. Humans are not immune to such brain manipulations; they typically exhibit strong emotional feelings. Human emotion researchers should not ignore these systems and simply look at the complex and highly variable culturally molded manifestations of emotions in humans if they wish to determine what kinds of "natural" emotional processes exist within all mammalian brain. Basic emotion science has generated workable epistemological strategies for under-standing the primal sources of human emotional feelings by detailed study of emotional circuits in our fellow animals.

  20. Integrating attentional control theory and the strength model of self-control

    PubMed Central

    Englert, Chris; Bertrams, Alex

    2015-01-01

    In the present article, we argue that it may be fruitful to incorporate the ideas of the strength model of self-control into the core assumptions of the well-established attentional control theory (ACT). In ACT, it is assumed that anxiety automatically leads to attention disruption and increased distractibility, which may impair subsequent cognitive or perceptual-motor performance, but only if individuals do not have the ability to counteract this attention disruption. However, ACT does not clarify which process determines whether one can volitionally regulate attention despite experiencing high levels of anxiety. In terms of the strength model of self-control, attention regulation can be viewed as a self-control act depending on the momentary availability of self-control strength. We review literature that has revealed that self-control strength moderates the anxiety–performance relationship, discuss how to integrate these two theoretical models, and offer practical recommendations of how to counteract negative anxiety effects. PMID:26136712

  1. Self-Control, Social Factors, and Delinquency: A Test of the General Theory of Crime among Adolescents in Hong Kong

    ERIC Educational Resources Information Center

    Cheung, Nicole W. T.; Cheung, Yuet W.

    2008-01-01

    The objectives of this study were to test the predictive power of self-control theory for delinquency in a Chinese context, and to explore if social factors as predicted in social bonding theory, differential association theory, general strain theory, and labeling theory have effects on delinquency in the presence of self-control. Self-report data…

  2. An introduction to stochastic control theory, path integrals and reinforcement learning

    NASA Astrophysics Data System (ADS)

    Kappen, Hilbert J.

    2007-02-01

    Control theory is a mathematical description of how to act optimally to gain future rewards. In this paper I give an introduction to deterministic and stochastic control theory and I give an overview of the possible application of control theory to the modeling of animal behavior and learning. I discuss a class of non-linear stochastic control problems that can be efficiently solved using a path integral or by MC sampling. In this control formalism the central concept of cost-to-go becomes a free energy and methods and concepts from statistical physics can be readily applied.

  3. Self-determination theory and diminished functioning: the role of interpersonal control and psychological need thwarting.

    PubMed

    Bartholomew, Kimberley J; Ntoumanis, Nikos; Ryan, Richard M; Bosch, Jos A; Thøgersen-Ntoumani, Cecilie

    2011-11-01

    Drawing from self-determination theory, three studies explored the social-environmental conditions that satisfy versus thwart psychological needs and, in turn, affect psychological functioning and well-being or ill-being. In cross-sectional Studies 1 and 2, structural equation modeling analyses supported latent factor models in which need satisfaction was predicted by athletes' perceptions of autonomy support, and need thwarting was better predicted by coach control. Athletes' perceptions of need satisfaction predicted positive outcomes associated with sport participation (vitality and positive affect), whereas need thwarting more consistently predicted maladaptive outcomes (disordered eating, burnout, depression, negative affect, and physical symptoms). In addition, athletes' perceptions of psychological need thwarting were significantly associated with perturbed physiological arousal (elevated levels of secretory immunoglobulin A) prior to training. The final study involved the completion of a diary and supported the relations observed in the cross-sectional studies at a daily level. These findings have important implications for the operationalization and measurement of interpersonal styles and psychological needs.

  4. A Test of Positive Affect Induction for Countering Self-Control Depletion in Cigarette Smokers

    PubMed Central

    Shmueli, Dikla; Prochaska, Judith J.

    2011-01-01

    OBJECTIVE The self-control strength model posits that exerting self-control on one task, such as resisting temptations, will deplete self-control and impair subsequent self-regulatory performance, such as controlling smoking. The current study examined interventions designed to replenish depleted self-control strength to prevent tobacco use by inducing positive affect. DESIGN In a 2×2 design, 200 participants were randomized to either (1) resist eating from a plate of desserts (high temptation) or from a plate of raw vegetables (low temptation) and then (2) undergo a positive or neutral affect induction. Two inductions were compared (video vs. writing technique). Participants were then given a 10-minute recess. MAIN OUTCOME MEASURE Whether or not participants smoked during the recess, assessed by self-report and biochemical verification, served as the primary dependent variable. RESULTS The interaction between depletion and exposure group was significant, Wald’s X2 = 9.66, df = 3, p <.05. Among those assigned to resist desserts, 65.5% to 85% smoked if they were in the neutral video or writing conditions versus 10.5% in the positive affect video group. CONCLUSION Positive affect elicited with a video was able to counteract the detrimental effects of self-control depletion on smoking behavior, while writing exercises were associated with smoking. Implications for tobacco cessation intervention are discussed. PMID:21553949

  5. Exploring the Utility of Social Control Theory for Youth Development: Issues of Attachment, Involvement, and Gender.

    ERIC Educational Resources Information Center

    Huebner, Angela J.; Betts, Sherry C.

    2002-01-01

    Investigated the utility of social control theory's attachment and involvement bonds as protective factors to examine gender differences in reports of delinquency and academic achievement. Surveys of 7th-12th graders indicated that although several of the involvement bond variables of social control theory were predictive of both delinquency and…

  6. APPLICATIONS OF MATHEMATICAL CONTROL THEORY TO ACCOUNTING AND BUDGETING: II. THE CONTINUOUS JOINT TRADING MADEL.

    DTIC Science & Technology

    The paper applies the mathematical control theory to the accounting network flows, where the flow rates are constrained by linear inequalities. The...cross section phase of the problem, which is characterized by linear programming, and the dynamic phase of the problem, which is characterized by control theory . (Author)

  7. Modeling transonic aerodynamic response using nonlinear systems theory for use with modern control theory

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.

    1993-01-01

    The presentation begins with a brief description of the motivation and approach that has been taken for this research. This will be followed by a description of the Volterra Theory of Nonlinear Systems and the CAP-TSD code which is an aeroelastic, transonic CFD (Computational Fluid Dynamics) code. The application of the Volterra theory to a CFD model and, more specifically, to a CAP-TSD model of a rectangular wing with a NACA 0012 airfoil section will be presented.

  8. Reduced state feedback gain computation. [optimization and control theory for aircraft control

    NASA Technical Reports Server (NTRS)

    Kaufman, H.

    1976-01-01

    Because application of conventional optimal linear regulator theory to flight controller design requires the capability of measuring and/or estimating the entire state vector, it is of interest to consider procedures for computing controls which are restricted to be linear feedback functions of a lower dimensional output vector and which take into account the presence of measurement noise and process uncertainty. Therefore, a stochastic linear model that was developed is presented which accounts for aircraft parameter and initial uncertainty, measurement noise, turbulence, pilot command and a restricted number of measurable outputs. Optimization with respect to the corresponding output feedback gains was performed for both finite and infinite time performance indices without gradient computation by using Zangwill's modification of a procedure originally proposed by Powell. Results using a seventh order process show the proposed procedures to be very effective.

  9. Why does offspring size affect performance? Integrating metabolic scaling with life-history theory

    PubMed Central

    Pettersen, Amanda K.; White, Craig R.; Marshall, Dustin J.

    2015-01-01

    Within species, larger offspring typically outperform smaller offspring. While the relationship between offspring size and performance is ubiquitous, the cause of this relationship remains elusive. By linking metabolic and life-history theory, we provide a general explanation for why larger offspring perform better than smaller offspring. Using high-throughput respirometry arrays, we link metabolic rate to offspring size in two species of marine bryozoan. We found that metabolism scales allometrically with offspring size in both species: while larger offspring use absolutely more energy than smaller offspring, larger offspring use proportionally less of their maternally derived energy throughout the dependent, non-feeding phase. The increased metabolic efficiency of larger offspring while dependent on maternal investment may explain offspring size effects—larger offspring reach nutritional independence (feed for themselves) with a higher proportion of energy relative to structure than smaller offspring. These findings offer a potentially universal explanation for why larger offspring tend to perform better than smaller offspring but studies on other taxa are needed. PMID:26559952

  10. Item Response Theory Applied to Factors Affecting the Patient Journey Towards Hearing Rehabilitation

    PubMed Central

    Chenault, Michelene; Berger, Martijn; Kremer, Bernd; Anteunis, Lucien

    2016-01-01

    To develop a tool for use in hearing screening and to evaluate the patient journey towards hearing rehabilitation, responses to the hearing aid rehabilitation questionnaire scales aid stigma, pressure, and aid unwanted addressing respectively hearing aid stigma, experienced pressure from others; perceived hearing aid benefit were evaluated with item response theory. The sample was comprised of 212 persons aged 55 years or more; 63 were hearing aid users, 64 with and 85 persons without hearing impairment according to guidelines for hearing aid reimbursement in the Netherlands. Bias was investigated relative to hearing aid use and hearing impairment within the differential test functioning framework. Items compromising model fit or demonstrating differential item functioning were dropped. The aid stigma scale was reduced from 6 to 4, the pressure scale from 7 to 4, and the aid unwanted scale from 5 to 4 items. This procedure resulted in bias-free scales ready for screening purposes and application to further understand the help-seeking process of the hearing impaired. PMID:28028428

  11. An integrative mechanistic account of psychological distress, therapeutic change and recovery: the Perceptual Control Theory approach.

    PubMed

    Higginson, Sally; Mansell, Warren; Wood, Alex M

    2011-03-01

    The exact nature and mechanisms of psychological change within psychological disorders remain unknown. This review aims to use a psychological framework known as Perceptual Control Theory (Powers, 1973, 2005; Powers, Clark, & McFarland, 1960) to integrate the diverse literature within psychotherapy research. The core principles of Perceptual Control Theory are explained, and key domains of psychotherapy are considered to explore how well they converge with these principles. The quantitative and qualitative empirical literature on the process of psychological change is reviewed to examine how it fits with predictions based on Perceptual Control Theory. Furthermore, the prerequisites for psychological change; client qualities, therapist qualities, the therapeutic alliance and the shifting of awareness, are also considered to examine their consistency within a Perceptual Control Theory account. Finally the strengths and limitations of a Perceptual Control Theory account in explaining the mechanism of psychological change are considered.

  12. Application of modern control theory to the design of optimum aircraft controllers

    NASA Technical Reports Server (NTRS)

    Power, L. J.

    1973-01-01

    The synthesis procedure presented is based on the solution of the output regulator problem of linear optimal control theory for time-invariant systems. By this technique, solution of the matrix Riccati equation leads to a constant linear feedback control law for an output regulator which will maintain a plant in a particular equilibrium condition in the presence of impulse disturbances. Two simple algorithms are presented that can be used in an automatic synthesis procedure for the design of maneuverable output regulators requiring only selected state variables for feedback. The first algorithm is for the construction of optimal feedforward control laws that can be superimposed upon a Kalman output regulator and that will drive the output of a plant to a desired constant value on command. The second algorithm is for the construction of optimal Luenberger observers that can be used to obtain feedback control laws for the output regulator requiring measurement of only part of the state vector. This algorithm constructs observers which have minimum response time under the constraint that the magnitude of the gains in the observer filter be less than some arbitrary limit.

  13. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1989-01-01

    The dynamic control module being developed in the Dynamic and Strategic Control of Cooperative Manipulators (DASCCOM) project at the Stanford University Aerospace Robotics Laboratory is described. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to the strategic controller. Experimental results for a dual two-link arm robotic system are presented to verify the controllers performance, for both free-motion slews and environmental contact.

  14. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1992-01-01

    This paper presents the dynamic control module of the Dynamic and Strategic Control of Cooperating Manipulators (DASCCOM) project at Stanford University's Aerospace Robotics Laboratory. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to higher level strategic control modules. Experimental results from a dual two-link-arm robotic system are used to compare the object impedance controller with other strategies, both for free-motion slews and environmental contact.

  15. Decentralized adaptive control of manipulators - Theory, simulation, and experimentation

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun

    1989-01-01

    The author presents a simple decentralized adaptive-control scheme for multijoint robot manipulators based on the independent joint control concept. The control objective is to achieve accurate tracking of desired joint trajectories. The proposed control scheme does not use the complex manipulator dynamic model, and each joint is controlled simply by a PID (proportional-integral-derivative) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. Simulation results are given for a two-link direct-drive manipulator under adaptive independent joint control. The results illustrate trajectory tracking under coupled dynamics and varying payload. The proposed scheme is implemented on a MicroVAX II computer for motion control of the three major joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite coupled nonlinear joint dynamics.

  16. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    USGS Publications Warehouse

    Williams, Wyatt I.; Friedman, Jonathan M.; Gaskin, John F.; Norton, Andrew P.

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western United States, and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Increased levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpins the importance of plant hybridization and may explain why some biological control releases are more successful than others.

  17. Process Dynamics and Control, a Theory-Experiential Approach.

    ERIC Educational Resources Information Center

    Perna, A. J.; And Others

    A required senior-level chemical engineering course at Colorado State University is described. The first nine weeks are devoted to the theory portion of the course, which includes the following topics: LaPlace transformations and time constants, block diagrams, inverse transformations, linearization, frequency response analysis, graphical…

  18. Load Theory of Selective Attention and Cognitive Control

    ERIC Educational Resources Information Center

    Lavie, Nilli; Hirst, Aleksandra; de Fockert, Jan W.; Viding, Essi

    2004-01-01

    A load theory of attention in which distractor rejection depends on the level and type of load involved in current processing was tested. A series of experiments demonstrates that whereas high perceptual load reduces distractor interference, working memory load or dual-task coordination load increases distractor interference. These findings…

  19. Unique interferometer experiment for controlling the theory of relativity

    NASA Astrophysics Data System (ADS)

    Abraham, Gyorgy; Wenzel, Klara; Halmai, Attila; Antal, Akos; Molnar, Laszlo A.

    1993-10-01

    Although modern theoretical physics states that the velocity of light does not add to the velocity of the light source, and so according to Einstein's theory the velocity of light is independent of the coordinate system, from time to time scientists try to disprove this axiom. We tried to build the most accurate experimental setup according to our technology.

  20. Neural Activation Underlying Cognitive Control in the Context of Neutral and Affectively Charged Pictures in Children

    ERIC Educational Resources Information Center

    Lamm, Connie; White, Lauren K.; McDermott, Jennifer Martin; Fox, Nathan A.

    2012-01-01

    The neural correlates of cognitive control for typically developing 9-year-old children were examined using dense-array ERPs and estimates of cortical activation (LORETA) during a go/no-go task with two conditions: a neutral picture condition and an affectively charged picture condition. Activation was estimated for the entire cortex after which…

  1. Further Analysis of Variables That Affect Self-Control with Aversive Events

    ERIC Educational Resources Information Center

    Perrin, Christopher J.; Neef, Nancy A.

    2012-01-01

    The purpose of this study was to examine variables that affect self-control in the context of academic task completion by elementary school children with autism. In the baseline assessment of Study 1, mathematics problem completion was shown to be an aversive event, and sensitivity to task magnitude, task difficulty, and delay to task completion…

  2. 40 CFR 60.5390 - What standards apply to pneumatic controller affected facilities?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What standards apply to pneumatic controller affected facilities? 60.5390 Section 60.5390 Protection of Environment ENVIRONMENTAL PROTECTION... reconstructed on or after October 15, 2013, at a location between the wellhead and a natural gas...

  3. 40 CFR 60.5390 - What standards apply to pneumatic controller affected facilities?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What standards apply to pneumatic controller affected facilities? 60.5390 Section 60.5390 Protection of Environment ENVIRONMENTAL PROTECTION... at a location between the wellhead and a natural gas processing plant must have a bleed rate...

  4. Dynamics of controlled release systems based on water-in-water emulsions: a general theory.

    PubMed

    Sagis, Leonard M C

    2008-10-06

    Phase-separated biopolymer solutions, and aqueous dispersions of hydrogel beads, liposomes, polymersomes, aqueous polymer microcapsules, and colloidosomes are all examples of water-in-water emulsions. These systems can be used for encapsulation and controlled release purposes, in for example food or pharmaceutical applications. The stress-deformation behavior of the droplets in these systems is very complex, and affected by mass transfer across the interface. The relaxation time of a deformation of a droplet may depend on interfacial properties such as surface tension, bending rigidity, spontaneous curvature, permeability, and interfacial viscoelasticity. It also depends on bulk viscoelasticity and composition. A non-equilibrium thermodynamic model is developed for the dynamic behavior of these systems, which incorporates all these parameters, and is based on the interfacial transport phenomena (ITP) formalism. The ITP formalism allows us to describe all water-in-water emulsions with one general theory. Phase-separated biopolymer solutions, and dispersions of hydrogel beads, liposomes, polymersomes, polymer microcapsules, and colloidosomes are basically limiting cases of this general theory with respect to bulk and interfacial rheological behavior.

  5. The glucostatic theory of appetite control and the risk of obesity and diabetes.

    PubMed

    Chaput, J-P; Tremblay, A

    2009-01-01

    More than 50 years ago, Jean Mayer proposed that changes in blood glucose concentrations or arteriovenous glucose differences are detected by glucoreceptors that affect energy intake. According to this theory, an increase in blood glucose concentrations results in increased feelings of satiety whereas a drop in blood glucose concentrations has the opposite effect. The pioneering work of Mayer has recently received support from our group as low glycemia has been shown to be linked with body weight gain prospectively and has been considered as a strong predictor of the amount of weight regained after weight loss. This state of mild hypoglycemia also predicts the increase in depressive symptoms with weight loss and a greater propensity to glucose intolerance and type 2 diabetes, particularly for individuals having short sleep durations. Furthermore, knowledge-based work has been shown to induce a significant increase in spontaneous energy intake being related to changes in glycemic control. In accordance with the glucostatic theory, this oriented review suggests that factors favoring a trend toward hypoglycemia and/or glucose instability might induce excess energy intake, overweight and impaired glucose tolerance. Data also raise the possibility that fat gain might be protective against mild hypoglycemia by providing compensation to the stimuli promoted by a modern environment.

  6. Status of dual control theory. [stochastic decision making

    NASA Technical Reports Server (NTRS)

    Tse, E.

    1975-01-01

    Theoretical studies of decision making and stochastic processes are discussed. Several approaches are described for an improved performing control method. It is shown that control performance is highly dependent on the knowledge of the unknown parameters in the system.

  7. Cognitive Evaluation Theory, Locus of Control and Positive Verbal Feedback.

    ERIC Educational Resources Information Center

    Lonky, Edward; Reihman, Jacqueline

    This study tests the hypothesis that individual differences in locus of control orientation may mediate elementary school students' responses to positive verbal feedback. A total of 30 kindergarten through fourth grade subjects were assessed for locus of control orientation using the Bialer Children's Locus of Control Questionnaire. To establish a…

  8. Complexity and simplicity of optimal control theory pulses shaped for controlling vibrational qubits.

    PubMed

    Shyshlov, Dmytro; Babikov, Dmitri

    2012-11-21

    In the context of molecular quantum computation the optimal control theory (OCT) is used to obtain shaped laser pulses for high-fidelity control of vibrational qubits. Optimization is done in time domain and the OCT algorithm varies values of electric field in each time step independently, tuning hundreds of thousands of parameters to find one optimal solution. Such flexibility is not available in experiments, where pulse shaping is done in frequency domain and the number of "tuning knobs" is much smaller. The question of possible experimental interpretations of theoretically found OCT solutions arises. In this work we analyze very accurate optimal pulse that we obtained for implementing quantum gate CNOT for the two-qubit system encoded into the exited vibrational states of thiophosgene molecule. Next, we try to alter this pulse by reducing the number of available frequency channels and intentionally introducing systematic and random errors (in frequency domain, by modifying the values of amplitudes and phases of different frequency components). We conclude that a very limited number of frequency components (only 32 in the model of thiophosgene) are really necessary for accurate control of the vibrational two-qubit system, and such pulses can be readily constructed using OCT. If the amplitude and phase errors of different frequency components do not exceed ±3% of the optimal values, one can still achieve accurate transformations of the vibrational two-qubit system, with gate fidelity of CNOT exceeding 0.99.

  9. The Caenorhabditis Elegans Unc-31 Gene Affects Multiple Nervous System-Controlled Functions

    PubMed Central

    Avery, L.; Bargmann, C. I.; Horvitz, H. R.

    1993-01-01

    We have devised a method for selecting Caenorhabditis elegans mutants that execute feeding motions in the absence of food. One mutation isolated in this way is an allele of the gene unc-31, first discovered by S. Brenner in 1974, because of its effects on locomotion. We find that strong unc-31 mutations cause defects in four functions controlled by the nervous system. Mutant worms are lethargic, feed constitutively, are defective in egg-laying and produce dauer larvae that fail to recover. We discuss two extreme models to explain this pleiotropy: either unc-31 affects one or a few neurons that coordinately control several different functions, or it affects many neurons that independently control different functions. PMID:8325482

  10. Investigation of practical applications of H infinity control theory to the design of control systems for large space structures

    NASA Technical Reports Server (NTRS)

    Irwin, R. Dennis

    1988-01-01

    The applicability of H infinity control theory to the problems of large space structures (LSS) control was investigated. A complete evaluation to any technique as a candidate for large space structure control involves analytical evaluation, algorithmic evaluation, evaluation via simulation studies, and experimental evaluation. The results of analytical and algorithmic evaluations are documented. The analytical evaluation involves the determination of the appropriateness of the underlying assumptions inherent in the H infinity theory, the determination of the capability of the H infinity theory to achieve the design goals likely to be imposed on an LSS control design, and the identification of any LSS specific simplifications or complications of the theory. The resuls of the analytical evaluation are presented in the form of a tutorial on the subject of H infinity control theory with the LSS control designer in mind. The algorthmic evaluation of H infinity for LSS control pertains to the identification of general, high level algorithms for effecting the application of H infinity to LSS control problems, the identification of specific, numerically reliable algorithms necessary for a computer implementation of the general algorithms, the recommendation of a flexible software system for implementing the H infinity design steps, and ultimately the actual development of the necessary computer codes. Finally, the state of the art in H infinity applications is summarized with a brief outline of the most promising areas of current research.

  11. Adaptive independent joint control of manipulators - Theory and experiment

    NASA Technical Reports Server (NTRS)

    Seraji, H.

    1988-01-01

    The author presents a simple decentralized adaptive control scheme for multijoint robot manipulators based on the independent joint control concept. The proposed control scheme for each joint consists of a PID (proportional integral and differential) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. The static and dynamic couplings that exist between the joint motions are compensated by the adaptive independent joint controllers while ensuring trajectory tracking. The proposed scheme is implemented on a MicroVAX II computer for motion control of the first three joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite strongly coupled, highly nonlinear joint dynamics. The results confirm that the proposed decentralized adaptive control of manipulators is feasible, in spite of strong interactions between joint motions. The control scheme presented is computationally very fast and is amenable to parallel processing implementation within a distributed computing architecture, where each joint is controlled independently by a simple algorithm on a dedicated microprocessor.

  12. Using behavioural activation in the treatment of depression: a control theory perspective.

    PubMed

    McEvoy, P; Law, A; Bates, R; Hylton, K; Mansell, W

    2013-12-01

    Behavioural activation is an intervention that can be used to counteract the typical patterns of withdrawal, avoidance and inactivity that characterize depression. This paper examines the processes of change that may occur during behavioural activation from the perspective of control theory. Some of the key concepts that are associated with control theory are introduced and the process of change that may occur during behavioural activation is illustrated using two case studies. The case studies provide anecdotal evidence which supports the hypothesis that the effective implementation of behavioural activation may depend upon clients being able to retain or regain the sense of control that they value. The differences between a control-theory-based approach and more orthodox behavioural and cognitive approaches are highlighted and the implications of these differences are discussed. Flexible approaches that are informed by control theory, may offer a useful alternative to the more established behavioural and cognitive approaches towards behavioural activation.

  13. Early life trauma is associated with altered white matter integrity and affective control.

    PubMed

    Corbo, Vincent; Amick, Melissa A; Milberg, William P; McGlinchey, Regina E; Salat, David H

    2016-08-01

    Early life trauma (ELT) has been shown to impair affective control and attention well into adulthood. Neuroimaging studies have further shown that ELT was associated with decreased white matter integrity in the prefrontal areas in children and adults. However, no study to date has looked at the relationship between white matter integrity and affective control in individuals with and without a history of ELT. To examine this, we tested 240 Veterans with (ELT N = 80) and without (NoELT N = 160) a history of childhood sexual abuse, physical abuse or family violence. Affective control was measured with the Affective Go/No-Go (AGN) and attention was indexed with the Test of Variable Attention (TOVA). White matter integrity was measured using fractional anisotropy (FA). Results showed greater number of errors on the AGN in ELT compared to NoELT. There was no difference on the TOVA. While there were no mean differences in FA, there was an interaction between FA and reaction time to positive stimuli on the AGN where the ELT group showed a positive relationship between FA and reaction time in right frontal and prefrontal areas, whereas the NoELT group showed a negative or no association between FA and reaction time. This suggests that ELT may be associated with a distinct brain-behavior relationship that could be related to other determinants of FA than those present in healthy adults.

  14. EXPLAINING THE ASSOCIATION BETWEEN GENDER AND SUBSTANCE USE AMONG AMERICAN INDIAN ADOLESCENTS: AN APPLICATION OF POWER-CONTROL THEORY

    PubMed Central

    Eitle, Tamela McNulty; Eitle, David

    2016-01-01

    This study evaluates the utility of Hagan’s power-control theory for explaining substance use behaviors for a sample of American Indian adolescent males and females. Consistent with the theory, we found that patriarchal family form and the affective bond between father and daughter were significant predictors of female substance use behaviors. Compared to results from an analysis of non-Hispanic whites, these results reveal the importance of testing generalist explanations of deviant behavior across racial and ethnic groups. Our findings encourage a more in depth consideration of the gendered nature of work, it’s association with socialization and control in American Indian families, and it’s impact on gender differences in substance use and delinquent behaviors. PMID:27313337

  15. EXPLAINING THE ASSOCIATION BETWEEN GENDER AND SUBSTANCE USE AMONG AMERICAN INDIAN ADOLESCENTS: AN APPLICATION OF POWER-CONTROL THEORY.

    PubMed

    Eitle, Tamela McNulty; Eitle, David

    2015-12-01

    This study evaluates the utility of Hagan's power-control theory for explaining substance use behaviors for a sample of American Indian adolescent males and females. Consistent with the theory, we found that patriarchal family form and the affective bond between father and daughter were significant predictors of female substance use behaviors. Compared to results from an analysis of non-Hispanic whites, these results reveal the importance of testing generalist explanations of deviant behavior across racial and ethnic groups. Our findings encourage a more in depth consideration of the gendered nature of work, it's association with socialization and control in American Indian families, and it's impact on gender differences in substance use and delinquent behaviors.

  16. Theory and Applications of Optimal Control in Aerospace Systems,

    DTIC Science & Technology

    1981-07-01

    CONTROL OF LINEAR QUADRATIC SYSTEM. Consider, as a particular case of the general problem defined in section 2, a lineal , system with quadratic cost... LARSON Proceeding of the IFAC Stochastic Control Symposium, Budapest, 1974. [36] G. CAMPION "Optimal control of non-linear stochastic systems by...dynamics, an r-component algebraic (or transcendental) equation representing the output, and an r-component equation representing the observation: dx (t

  17. Basic Research in the Mathematical Foundations of Stability Theory, Control Theory and Numerical Linear Algebra.

    DTIC Science & Technology

    1979-09-01

    without determinantal divisors, Linear and Multilinear Algebra 7(1979), 107-109. 4. The use of integral operators in number theory (with C. Ryavec and...Gersgorin revisited, to appear in Letters in Linear Algebra. 15. A surprising determinantal inequality for real matrices (with C.R. Johnson), to appear in...Analysis: An Essay Concerning the Limitations of Some Mathematical Methods in the Social , Political and Biological Sciences, David Berlinski, MIT Press

  18. Evidence for an inhibitory-control theory of the reasoning brain.

    PubMed

    Houdé, Olivier; Borst, Grégoire

    2015-01-01

    In this article, we first describe our general inhibitory-control theory and, then, we describe how we have tested its specific hypotheses on reasoning with brain imaging techniques in adults and children. The innovative part of this perspective lies in its attempt to come up with a brain-based synthesis of Jean Piaget's theory on logical algorithms and Daniel Kahneman's theory on intuitive heuristics.

  19. Evidence for an inhibitory-control theory of the reasoning brain

    PubMed Central

    Houdé, Olivier; Borst, Grégoire

    2015-01-01

    In this article, we first describe our general inhibitory-control theory and, then, we describe how we have tested its specific hypotheses on reasoning with brain imaging techniques in adults and children. The innovative part of this perspective lies in its attempt to come up with a brain-based synthesis of Jean Piaget’s theory on logical algorithms and Daniel Kahneman’s theory on intuitive heuristics. PMID:25852528

  20. Differentiating between precursor and control variables when analyzing reasoned action theories.

    PubMed

    Hennessy, Michael; Bleakley, Amy; Fishbein, Martin; Brown, Larry; Diclemente, Ralph; Romer, Daniel; Valois, Robert; Vanable, Peter A; Carey, Michael P; Salazar, Laura

    2010-02-01

    This paper highlights the distinction between precursor and control variables in the context of reasoned action theory. Here the theory is combined with structural equation modeling to demonstrate how age and past sexual behavior should be situated in a reasoned action analysis. A two wave longitudinal survey sample of African-American adolescents is analyzed where the target behavior is having vaginal sex. Results differ when age and past behavior are used as control variables and when they are correctly used as precursors. Because control variables do not appear in any form of reasoned action theory, this approach to including background variables is not correct when analyzing data sets based on the theoretical axioms of the Theory of Reasoned Action, the Theory of Planned Behavior, or the Integrative Model.

  1. Differentiating Between Precursor and Control Variables When Analyzing Reasoned Action Theories

    PubMed Central

    Hennessy, Michael; Bleakley, Amy; Fishbein, Martin; Brown, Larry; DiClemente, Ralph; Romer, Daniel; Valois, Robert; Vanable, Peter A.; Carey, Michael P.; Salazar, Laura

    2010-01-01

    This paper highlights the distinction between precursor and control variables in the context of reasoned action theory. Here the theory is combined with structural equation modeling to demonstrate how age and past sexual behavior should be situated in a reasoned action analysis. A two wave longitudinal survey sample of African-American adolescents is analyzed where the target behavior is having vaginal sex. Results differ when age and past behavior are used as control variables and when they are correctly used as precursors. Because control variables do not appear in any form of reasoned action theory, this approach to including background variables is not correct when analyzing data sets based on the theoretical axioms of the Theory of Reasoned Action, the Theory of Planned Behavior, or the Integrative Model PMID:19370408

  2. Effects of a National Public Service Information Campaign on Crime Prevention: Perspectives from Social Learning and Social Control Theory.

    ERIC Educational Resources Information Center

    Lordan, Edward J.; Kwon, Joongrok

    This study examined the effects of public service advertising from two theoretical backgrounds: social learning theory and social control theory. Traditional social learning theory assumes that learning occurs by subjects performing responses and experiencing their effects, with reinforcement as the main determinant. Social control theory, as…

  3. Theory of perturbative pulse train based coherent control

    NASA Astrophysics Data System (ADS)

    Grinev, Timur; Brumer, Paul

    2014-03-01

    A theoretical description of coherent control of excited state dynamics using pulse trains in the perturbative regime, as carried out in recent experiments, is presented. Analytical expressions relating the excited state populations to the pulse train control parameters are derived. Numerical examples are provided for models of pyrazine and β-carotene, and the significant role of overlapping resonances is exposed.

  4. Stimulus control topography coherence theory: Foundations and extensions

    PubMed Central

    McIlvane, William J.; Dube, William V.

    2003-01-01

    Stimulus control topography refers to qualitative differences among members of a functional stimulus class. Stimulus control topography coherence refers to the degree of concordance between the stimulus properties specified as relevant by the individual arranging a reinforcement contingency (behavior analyst, experimenter, teacher, etc.) and the stimulus properties that come to control the behavior of the organism (experimental subject, student, etc.) that experiences those contingencies. This paper summarizes the rationale for analyses of discrimination learning outcomes in terms of stimulus control topography coherence and briefly reviews some of the foundational studies that led to this perspective. We also suggest directions for future research, including pursuit of conceptual and methodological challenges to a complete stimulus control topography coherence analysis of processes involved in discriminated and generalized operants. ImagesFigure 3Figure 5 PMID:22478402

  5. Configuration control of redundant manipulators - Theory and implementation

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun

    1989-01-01

    A simple approach for controlling the manipulator configuration over the entire motion is presented, based on augmentation of the manipulator forward kinematics. User-defined kinematic functions and the end-effector Cartesian coordinates are combined to form a set of task-related configuration variables as generalized coordinates for the manipulator. A task-based adaptive scheme is then utilized to control the configuration variables and achieve tracking of the desired reference trajectories. This achieves the desired end-effector motion while utilizing redundancy to achieve any additional task. Simulation results for a direct-drive two-link arm are given to illustrate the proposed control scheme. The scheme has also been implemented for real-time control of three links of a PUMA 560 industrial robot. The simulation and experimental results validate the configuration control scheme and demonstrate its capabilities for performing various realistic tasks.

  6. Race, Gender, Single-Mother Households, and Delinquency: A Further Test of Power-Control Theory

    ERIC Educational Resources Information Center

    Mack, Kristin Y.; Leiber, Michael J.

    2005-01-01

    Using power-control theory as the theoretical framework, the present study examines the gender gap in delinquency for White and African American youth from single-mother households. The research is driven by the need to focus more attention on understanding how delinquency theories apply across different racial groups. Results from both bivariate…

  7. Heavy Episodic Drinking among Adolescents: A Test of Hypotheses Derived from Control Theory

    ERIC Educational Resources Information Center

    Costello, Barbara J.; Anderson, Bradley J.; Stein, Michael D.

    2006-01-01

    Despite a growing body of literature on the causes of heavy episodic drinking, little attention has been paid to this phenomenon in the sociological and criminological literature. This research assesses the extent to which a popular theory of crime and deviance, control theory, can explain heavy episodic drinking. Analysis of data collected from a…

  8. OPTIMAL CONTROL THEORY APPLIED TO SYSTEMS DESCRIBED BY PARTIAL DIFFERENTIAL EQUATIONS. VOL. 1 OF FINAL REPORT.

    DTIC Science & Technology

    control theory to systems described by partial differential equations. The intent is not to advance the theory of partial differential equations per se. Thus all considerations will be restricted to the more familiar equations of the type which often occur in mathematical physics. Specifically, the distributed parameter systems under consideration are represented by a set of field

  9. Theory of Mind, Inhibitory Control, and Preschool-Age Children's Suggestibility in Different Interviewing Contexts

    ERIC Educational Resources Information Center

    Scullin, Matthew H.; Bonner, Karri

    2006-01-01

    The current study examined the relations among 3- to 5-year-olds' theory of mind, inhibitory control, and three measures of suggestibility: yielding to suggestive questions (yield), shifting answers in response to negative feedback (shift), and accuracy in response to misleading questions during a pressured interview about a live event. Theory of…

  10. A causal role for the anterior mid-cingulate cortex in negative affect and cognitive control.

    PubMed

    Tolomeo, Serenella; Christmas, David; Jentzsch, Ines; Johnston, Blair; Sprengelmeyer, Reiner; Matthews, Keith; Douglas Steele, J

    2016-06-01

    Converging evidence has linked the anterior mid-cingulate cortex to negative affect, pain and cognitive control. It has previously been proposed that this region uses information about punishment to control aversively motivated actions. Studies on the effects of lesions allow causal inferences about brain function; however, naturally occurring lesions in the anterior mid-cingulate cortex are rare. In two studies we therefore recruited 94 volunteers, comprising 15 patients with treatment-resistant depression who had received bilateral anterior cingulotomy, which consists of lesions made within the anterior mid-cingulate cortex, 20 patients with treatment-resistant depression who had not received surgery and 59 healthy control subjects. Using the Ekman 60 faces paradigm and two Stroop paradigms, we tested the hypothesis that patients who received anterior cingulotomy were impaired in recognizing negative facial affect expressions but not positive or neutral facial expressions, and impaired in Stroop cognitive control, with larger lesions being associated with more impairment. Consistent with this hypothesis, we found that larger volume lesions predicted more impairment in recognizing fear, disgust and anger, and no impairment in recognizing facial expressions of surprise or happiness. However, we found no impairment in recognizing expressions of sadness. Also consistent with the hypothesis, we found that larger volume lesions predicted impaired Stroop cognitive control. Notably, this relationship was only present when anterior mid-cingulate cortex lesion volume was defined as the overlap between cingulotomy lesion volume and Shackman's meta-analysis-derived binary masks for negative affect and cognitive control. Given substantial evidence from healthy subjects that the anterior mid-cingulate cortex is part of a network associated with the experience of negative affect and pain, engaging cognitive control processes for optimizing behaviour in the presence of such

  11. A Case Controlled Examination of the Interpersonal Theory of Suicide in the Second Half of Life.

    PubMed

    Van Orden, Kimberly A; Smith, Phillip N; Chen, Tian; Conwell, Yeates

    2016-07-02

    The interpersonal theory of suicide proposes that the most proximal cause of suicide is the combination of thwarted belongingness and perceived burdensomeness coupled with a pre-existing vulnerability of reduced fear of death and increased pain tolerance. This pre-existing vulnerability develops in response to painful and provocative life events. According to the theory, empirically demonstrated risk factors for suicide operate by increasing the likelihood of one or more of the theory's constructs. The current study examined the relations of the major constructs of the interpersonal theory with suicide case status compared to living controls in the second half of life. The current study used a pre-existing psychological autopsy database to compare suicide decedents to living controls 50 years and older. Theory constructs were measured by composite scores of thwarted belongingness, perceived burdensomeness, and painful and provocative experiences using an a priori selection of items comprising each construct. Suicide decedents experienced greater levels of all three of the theory's constructs when examined independently compared to living controls. When examined simultaneously while also controlling for Major Depression, greater perceived burdensomeness and painful and provocative experiences were associated with suicide case status (vs. control). The interpersonal theory is a comprehensive framework that may be useful in understanding risk for death by suicide in the second half of life. Clinical management of suicide risk for adults in the second half of life could include a focus on perceived burdensomeness, as the IPTS proposes that this psychological state is amenable to change via therapeutic intervention.

  12. SYMBOLIC ALGEBRAIC MANIPULATION BY DIGITAL COMPUTER IN PROBLEMS OF CONTROL THEORY.

    DTIC Science & Technology

    shown, using a FORMAC program. The advantages over the conventional root locus method are discussed. Areas of possible future use of FORMAC in algebraic problems of control theory are discussed. (Author)

  13. A control theory model for human decision making

    NASA Technical Reports Server (NTRS)

    Levison, W. H.

    1972-01-01

    The optimal control model for pilot-vehicle systems has been extended to handle certain types of human decision tasks. The model for decision making incorporates the observation noise, optimal estimation, and prediction concepts that form the basis of the model for control behavior. Experiments are described for the following task situations: (1) single decision tasks; (2) two decision tasks; and (3) simultaneous manual control and decision tasks. Using fixed values for model parameters, single-task and two-task decision performance scores to within an accuracy of 10 percent can be predicted. The experiment on simultaneous control and decision indicates the presence of task interference in this situation, but the results are not adequate to allow a conclusive test of the predictive capability of the model.

  14. A control-theory model for human decision-making

    NASA Technical Reports Server (NTRS)

    Levison, W. H.; Tanner, R. B.

    1971-01-01

    A model for human decision making is an adaptation of an optimal control model for pilot/vehicle systems. The models for decision and control both contain concepts of time delay, observation noise, optimal prediction, and optimal estimation. The decision making model was intended for situations in which the human bases his decision on his estimate of the state of a linear plant. Experiments are described for the following task situations: (a) single decision tasks, (b) two-decision tasks, and (c) simultaneous manual control and decision making. Using fixed values for model parameters, single-task and two-task decision performance can be predicted to within an accuracy of 10 percent. Agreement is less good for the simultaneous decision and control situation.

  15. Work locus of control and its relationship to stress perception, related affections, attitudes and behaviours from a domain-specific perspective.

    PubMed

    Tong, Jiajin; Wang, Lei

    2012-08-01

    This research aims to examine the value of applying the Work Locus of Control Scale in predicting work-related outcomes. Study 1 surveyed 323 employees from different companies in China and found that the domain-specific scale was more predictive than the general scale in predicting perceived stressors, rather than in predicting organizational affective commitment and altruistic behaviour. Study 2 applied a multi-wave and multi-source design and used commensurate Likert scales to measure work and general locus of control. Participants were 344 employees from one corporation. Work locus of control was found to be more useful in predicting supervisor-rated job performance, conscientious and altruistic behaviours. These findings help understand the theory-based and measurement-based reasons for the advantages of using domain-specific measures. They claim the importance for employing the domain-specific measure to predict work-related perceptions and behaviours. Implications for the theory and practice are discussed.

  16. 45 CFR 2526.30 - How do convictions for the possession or sale of controlled substances affect an education award...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... controlled substances affect an education award recipient's ability to use that award? 2526.30 Section 2526... of controlled substances affect an education award recipient's ability to use that award? (a) Except... under pertinent Federal or State law of the possession or sale of a controlled substance is not...

  17. 25 CFR 542.4 - How do these regulations affect minimum internal control standards established in a Tribal-State...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false How do these regulations affect minimum internal control... COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN SERVICES MINIMUM INTERNAL CONTROL STANDARDS § 542.4 How do these regulations affect minimum internal control standards established in a Tribal-State compact? (a) If there is...

  18. Reconsideration of r/K Selection Theory Using Stochastic Control Theory and Nonlinear Structured Population Models.

    PubMed

    Oizumi, Ryo; Kuniya, Toshikazu; Enatsu, Yoichi

    2016-01-01

    Despite the fact that density effects and individual differences in life history are considered to be important for evolution, these factors lead to several difficulties in understanding the evolution of life history, especially when population sizes reach the carrying capacity. r/K selection theory explains what types of life strategies evolve in the presence of density effects and individual differences. However, the relationship between the life schedules of individuals and population size is still unclear, even if the theory can classify life strategies appropriately. To address this issue, we propose a few equations on adaptive life strategies in r/K selection where density effects are absent or present. The equations detail not only the adaptive life history but also the population dynamics. Furthermore, the equations can incorporate temporal individual differences, which are referred to as internal stochasticity. Our framework reveals that maximizing density effects is an evolutionarily stable strategy related to the carrying capacity. A significant consequence of our analysis is that adaptive strategies in both selections maximize an identical function, providing both population growth rate and carrying capacity. We apply our method to an optimal foraging problem in a semelparous species model and demonstrate that the adaptive strategy yields a lower intrinsic growth rate as well as a lower basic reproductive number than those obtained with other strategies. This study proposes that the diversity of life strategies arises due to the effects of density and internal stochasticity.

  19. Reconsideration of r/K Selection Theory Using Stochastic Control Theory and Nonlinear Structured Population Models

    PubMed Central

    Oizumi, Ryo; Kuniya, Toshikazu; Enatsu, Yoichi

    2016-01-01

    Despite the fact that density effects and individual differences in life history are considered to be important for evolution, these factors lead to several difficulties in understanding the evolution of life history, especially when population sizes reach the carrying capacity. r/K selection theory explains what types of life strategies evolve in the presence of density effects and individual differences. However, the relationship between the life schedules of individuals and population size is still unclear, even if the theory can classify life strategies appropriately. To address this issue, we propose a few equations on adaptive life strategies in r/K selection where density effects are absent or present. The equations detail not only the adaptive life history but also the population dynamics. Furthermore, the equations can incorporate temporal individual differences, which are referred to as internal stochasticity. Our framework reveals that maximizing density effects is an evolutionarily stable strategy related to the carrying capacity. A significant consequence of our analysis is that adaptive strategies in both selections maximize an identical function, providing both population growth rate and carrying capacity. We apply our method to an optimal foraging problem in a semelparous species model and demonstrate that the adaptive strategy yields a lower intrinsic growth rate as well as a lower basic reproductive number than those obtained with other strategies. This study proposes that the diversity of life strategies arises due to the effects of density and internal stochasticity. PMID:27336169

  20. Long-Term Exposure to High Altitude Affects Conflict Control in the Conflict-Resolving Stage.

    PubMed

    Ma, Hailin; Wang, Yan; Wu, Jianhui; Wang, Baoxi; Guo, Shichun; Luo, Ping; Han, Buxin

    2015-01-01

    The neurocognitive basis of the effect of long-term high altitude exposure on conflict control is unclear. Event related potentials (ERPs) were recorded in a flanker task to investigate the influence of high altitude on conflict control in the high-altitude group (who had lived at high altitude for three years but were born at low altitude) and the low-altitude group (living in low altitude only). Although altitude effect was not significant at the behavioral level, ERPs showed cognitive conflict modulation. The interaction between group and trial type was significant: P3 amplitude was greater in the low-altitude group than in the high-altitude group in the incongruent trial. This result suggests that long-term exposure to high altitude affects conflict control in the conflict-resolving stage, and that attentional resources are decreased to resist the conflict control in the high-altitude group.

  1. Robust stabilization control based on guardian maps theory for a longitudinal model of hypersonic vehicle.

    PubMed

    Liu, Yanbin; Liu, Mengying; Sun, Peihua

    2014-01-01

    A typical model of hypersonic vehicle has the complicated dynamics such as the unstable states, the nonminimum phases, and the strong coupling input-output relations. As a result, designing a robust stabilization controller is essential to implement the anticipated tasks. This paper presents a robust stabilization controller based on the guardian maps theory for hypersonic vehicle. First, the guardian maps theories are provided to explain the constraint relations between the open subsets of complex plane and the eigenvalues of the state matrix of closed-loop control system. Then, a general control structure in relation to the guardian maps theories is proposed to achieve the respected design demands. Furthermore, the robust stabilization control law depending on the given general control structure is designed for the longitudinal model of hypersonic vehicle. Finally, a simulation example is provided to verify the effectiveness of the proposed methods.

  2. Robust Stabilization Control Based on Guardian Maps Theory for a Longitudinal Model of Hypersonic Vehicle

    PubMed Central

    Liu, Mengying; Sun, Peihua

    2014-01-01

    A typical model of hypersonic vehicle has the complicated dynamics such as the unstable states, the nonminimum phases, and the strong coupling input-output relations. As a result, designing a robust stabilization controller is essential to implement the anticipated tasks. This paper presents a robust stabilization controller based on the guardian maps theory for hypersonic vehicle. First, the guardian maps theories are provided to explain the constraint relations between the open subsets of complex plane and the eigenvalues of the state matrix of closed-loop control system. Then, a general control structure in relation to the guardian maps theories is proposed to achieve the respected design demands. Furthermore, the robust stabilization control law depending on the given general control structure is designed for the longitudinal model of hypersonic vehicle. Finally, a simulation example is provided to verify the effectiveness of the proposed methods. PMID:24795535

  3. Adaptive Control and Guidance for Tactical Missiles. Volume 1: Parts 1 and 2. Introduction and Adaptive Control Theory

    DTIC Science & Technology

    varying airframe dynamics. Guidance techniques for tactical missiles are also reviewed and a number of steering laws, derived from optimal control ... theory , are evaluated. Quantitative comparisons are made between different guidance laws on the basis of intercept accuracy and control effort expended.

  4. ORACLS - A modern control theory design package. [Optimal Regulator Algorithms for Control of Linear Systems computer program

    NASA Technical Reports Server (NTRS)

    Armstrong, E. S.

    1975-01-01

    A digital computer program (ORACLS) for implementing the optimal regulator theory approach to the design of controllers for linear time-invariant systems is described. The user-oriented program employs the latest numerical techniques and is applicable to both the digital and continuous control problems.

  5. Proactive and reactive control of movement are differently affected in Attention Deficit Hyperactivity Disorder children.

    PubMed

    Pani, P; Menghini, D; Napolitano, C; Calcagni, M; Armando, M; Sergeant, J A; Vicari, S

    2013-10-01

    Attention-Deficit/Hyperactivity Disorder children are impaired in the ability to interrupt an ongoing action in relation to a sudden change in the environment (reactive control, measured by stop signal reaction time, SSRT). Less investigated is the ability to control the response when it is known in advance that it will be required to stop (proactive control, measured by change in Reaction time, RT). The study is aimed at exploring both the reactive and the proactive inhibitory control in a group of ADHD children compared to a group of age-matched controls. ADHD children (N=28) and Controls (N=28) performed 4 tasks: 2 tasks required to respond to the appearance of the go-signals (go task and nostop task) and 2 tasks to respond to the go signals in a context in which sometimes a restrain or suppression of the response was required (go-nogo task and stop task). ADHD children showed a longer SSRT compared to controls. Both groups showed an increment in RT by comparing the go-nogo to the go task and an increment in RT and SD by comparing the stop to the nostop task. ADHD children showed higher intra-individual variability (SD) compared to controls only in the stop and nostop task. ADHD children showed impaired reactive control but preserved proactive control, and the physical appearance of the go signal affected their reaction times intra-individual variability. A comparison between the reactive and proactive controls helps in defining neuropsychological profiles of ADHD children and can inspires therapeutic behavioral-cognitive strategies for response control.

  6. On stability theory. [of nonlinear feedback control systems

    NASA Technical Reports Server (NTRS)

    Safonov, M. G.; Athans, M.

    1979-01-01

    It is found that under mild assumptions, feedback system stability can be concluded if one can 'topologically separate' the infinite-dimensional function space containing the system's dynamical input-output relations into two regions, one region containing the dynamical input-output relation of the 'feedforward' element of the system and the other region containing the dynamical output-input relation of the 'feedback' element. Nonlinear system stability criteria of both the input-output type and the state-space (Liapunov) type are interpreted in this context. The abstract generality and conceptual simplicity afforded by the topological separation perspective clarifies some of the basic issues underlying stability theory and serves to suggest improvements in existing stability criteria. A generalization of Zames' (1966) conic-relation stability criterion is proved, laying the foundation for improved multivariable generalizations of the frequency-domain circle stability criterion for nonlinear systems.

  7. Contextual control of conditioning is not affected by extinction in a behavioral task with humans.

    PubMed

    Nelson, James Byron; Lamoureux, Jeffrey A

    2015-06-01

    The Attentional Theory of Context Processing (ATCP) states that extinction will arouse attention to contexts resulting in learning becoming contextually controlled. Participants learned to suppress responding to colored sensors in a video-game task where contexts were provided by different gameplay backgrounds. Four experiments assessed the contextual control of simple excitatory learning acquired to a test stimulus (T) after (Exp. 1) or during (Exp. 2-4) extinction of another stimulus (X). Experiment 1 produced no evidence of contextual control of T, though renewal to X was present both at the time T was trained and tested. In Experiment 2 no contextual control of T was evident when X underwent extensive conditioning and extinction. In Experiment 3 no contextual control of T was evident after extensive conditioning and extinction of X, and renewal to X was present. In Experiment 4 contextual control was evident to T, but it neither depended upon nor was enhanced by extinction of X. The results presented here appear to limit the generality of ATCP.

  8. Constrained modes in control theory - Transmission zeros of uniform beams

    NASA Technical Reports Server (NTRS)

    Williams, T.

    1992-01-01

    Mathematical arguments are presented demonstrating that the well-established control system concept of the transmission zero is very closely related to the structural concept of the constrained mode. It is shown that the transmission zeros of a flexible structure form a set of constrained natural frequencies for it, with the constraints depending explicitly on the locations and the types of sensors and actuators used for control. Based on this formulation, an algorithm is derived and used to produce dimensionless plots of the zero of a uniform beam with a compatible sensor/actuator pair.

  9. Closing the Gap Between Process Control Theory and Practice

    ERIC Educational Resources Information Center

    Velazquez, Carlos; Cardona-Martinez, Nelson; Velazquez, Edwin

    2010-01-01

    The pressure on world-wide manufacturing industries to meet tougher demands and regulations has forced companies to focus on improving manufacturing using tools like process automation. This focus requires better-prepared students. The process control course of the Department of Chemical Engineering at the University of Puerto Rico at Mayaguez has…

  10. Towards a Theory of Psychosocial Development and Fertility Control.

    ERIC Educational Resources Information Center

    Cvetkovich, George

    It is popularly held that the low rate of birth control use among sexually-active American teenagers is primarily due to their immaturity. Many teenagers are commencing their sexual careers prior to acquisition of the social and cognitive abilities demanded by responsible contraceptive use. A general decision-making framework can be used to create…

  11. Analysis of Information Systems Based on Automatic Control Theory,

    DTIC Science & Technology

    The development of information systems in the USSR have given rise to increased interest in studing them. In this report basic attention is given...to the problems of optimizing the operation and control of information systems . It appears that this problem can be solved most fruitfully on the basis

  12. Authority Control for Creators in Italy: Theory and Practice

    ERIC Educational Resources Information Center

    Savoja, Maurizio; Vitali, Stefano

    2007-01-01

    The first part of the article illustrates the connections between the debate on "ISAAR(CPF)" and archival authority control and the discussions about the nature of archives and their relationships with their creators that have taken place within the Italian archival community during the twentieth century. The second part of the article…

  13. Learned Helplessness: A Theory for the Age of Personal Control.

    ERIC Educational Resources Information Center

    Peterson, Christopher; And Others

    Experiences with uncontrollable events may lead to the expectation that future events will elude control, resulting in disruptions in motivation, emotion, and learning. This text explores this phenomenon, termed learned helplessness, tracking it from its discovery to its entrenchment in the psychological canon. The volume summarizes and integrates…

  14. Control Engineering, System Theory and Mathematics: The Teacher's Challenge

    ERIC Educational Resources Information Center

    Zenger, K.

    2007-01-01

    The principles, difficulties and challenges in control education are discussed and compared to the similar problems in the teaching of mathematics and systems science in general. The difficulties of today's students to appreciate the classical teaching of engineering disciplines, which are based on rigorous and scientifically sound grounds, are…

  15. Optimizing SFR transmutation performance through direct adjoining control theory

    NASA Astrophysics Data System (ADS)

    Davis, Jeffrey C.

    2007-12-01

    We have developed the CORTANA code to optimize the transmutation performance of sodium cooled fast reactors (SFRs). We obtain the necessary conditions for optimal fuel and burnable absorber loadings using Pontryagin's maximum principle with a direct adjoining approach to explicitly account for either a flat flux or a power peaking inequality constraint providing a set of coupled system, Euler-Lagrange (E-L), and optimality equations which are iteratively solved with the method of conjugate gradients until no further improvement in the objective function is achieved. To satisfy the inequality constraints throughout the operating cycle, we have implemented a backwards diffusion theory (BDT) to establish a relationship between fuel loading and the relative assembly power distribution during the cycle and systematically eliminate the constraint violations with each conjugate gradient iteration. The CORTANA SFR optimization code uses multi-group, three-dimensional neutron diffusion theory, with a microscopic depletion scheme. We solve the system equations in a quasi-static fashion forward in time from beginning-of-cycle (BOC) to end-of-cycle (EOC), while we solve the E-L equations backwards in time from EOC to BOC, reflecting the adjoint nature of the Lagrange multipliers. A two enrichment-zone SFR problem verifies our formulation, yielding a TRU enrichment distribution nearly identical to that of the reference SFR core in the Generation IV Roadmap. Using a full heavy metal recycling mode, we coupled our optimization methodology with the REBUS-3 equilibrium cycle methodology to optimize an SFR operating as a second tier transmuter. We model the system using a three-dimensional triangular-z finite differencing scheme with full core symmetry and a time-independent 33-group microscopic cross section library. Beginning from a uniform TRU distribution, our CORTANA improves the SFR performance by reducing the maximum relative assembly power from 1.7 to 1.25, minimizes

  16. The importance of behavior theory in control system modeling of physical activity sensor data.

    PubMed

    Riley, William T; Martin, Cesar A; Rivera, Daniel E

    2014-01-01

    Among health behaviors, physical activity has the most extensive record of research using passive sensors. Control systems and other system dynamic approaches have long been considered applicable for understanding human behavior, but only recently has the technology provided the precise and intensive longitudinal data required for these analytic approaches. Although sensors provide intensive data on the patterns and variations of physical activity over time, the influences of these variations are often unmeasured. Health behavior theories provide an explanatory framework of the putative mediators of physical activity changes. Incorporating the intensive longitudinal measurement of these theoretical constructs is critical to improving the fit of control system model of physical activity and for advancing behavioral theory. Theory-based control models also provide guidance on the nature of the controllers which serve as the basis for just-in-time adaptive interventions based on these control system models.

  17. A general test of self-control theory: has its importance been exaggerated?

    PubMed

    Cretacci, Michael A

    2008-10-01

    Self-control theory has been tested for 2 decades. However, mixed results and measurement problems have made it difficult to ascertain its true utility. This study addresses recent concerns and includes variables such as risk, consequences, criminal opportunity, an interaction term, and bond controls in one complete test. It also addresses self-control's ability to explain different forms of crime and whether the support that it has garnered has been exaggerated. Results of both cross-sectional and semilongitudinal tests indicate that self-control significantly predicts a higher probability of involvement in property and drug crime but is virtually silent in its ability to explain violence. Furthermore, it can be tentatively stated that support for the theory wanes over time. Finally, neglected concepts such as opportunity, risk, consequences, and bond controls may be important to the theory's ability to explain crime, and further negligence of these concepts may hamper a true understanding of its impact.

  18. Attentional control theory: anxiety, emotion, and motor planning.

    PubMed

    Coombes, Stephen A; Higgins, Torrie; Gamble, Kelly M; Cauraugh, James H; Janelle, Christopher M

    2009-12-01

    The present study investigated how trait anxiety alters the balance between attentional control systems to impact performance of a discrete preplanned goal-directed motor task. Participants executed targeted force contractions (engaging the goal-directed attentional system) at the offset of emotional and non-emotional distractors (engaging the stimulus-driven attentional system). High and low anxious participants completed the protocol at two target force levels (10% and 35% of maximum voluntary contraction). Reaction time (RT), performance accuracy, and rate of change of force were calculated. Expectations were confirmed at the 10% but not the 35% target force level: (1) high anxiety was associated with slower RTs, and (2) threat cues lead to faster RTs independently of trait anxiety. These new findings suggest that motor efficiency, but not motor effectiveness is compromised in high relative to low anxious individuals. We conclude that increased stimulus-driven attentional control interferes with movements that require greater attentional resources.

  19. Theory of feedback controlled brain stimulations for Parkinson's disease

    NASA Astrophysics Data System (ADS)

    Sanzeni, A.; Celani, A.; Tiana, G.; Vergassola, M.

    2016-01-01

    Limb tremor and other debilitating symptoms caused by the neurodegenerative Parkinson's disease are currently treated by administering drugs and by fixed-frequency deep brain stimulation. The latter interferes directly with the brain dynamics by delivering electrical impulses to neurons in the subthalamic nucleus. While deep brain stimulation has shown therapeutic benefits in many instances, its mechanism is still unclear. Since its understanding could lead to improved protocols of stimulation and feedback control, we have studied a mathematical model of the many-body neural network dynamics controlling the dynamics of the basal ganglia. On the basis of the results obtained from the model, we propose a new procedure of active stimulation, that depends on the feedback of the network and that respects the constraints imposed by existing technology. We show by numerical simulations that the new protocol outperforms the standard ones for deep brain stimulation and we suggest future experiments that could further improve the feedback procedure.

  20. Theory of Laser-Controlled Competing Superconducting and Charge Orders

    NASA Astrophysics Data System (ADS)

    Sentef, M. A.; Tokuno, A.; Georges, A.; Kollath, C.

    2017-02-01

    We investigate the nonequilibrium dynamics of competing coexisting superconducting (SC) and charge-density wave (CDW) orders in an attractive Hubbard model. A time-periodic laser field A →(t ) lifts the SC-CDW degeneracy, since the CDW couples linearly to the field (A →), whereas SC couples in second order (A→2) due to gauge invariance. This leads to a striking resonance: When the photon energy is red detuned compared to the equilibrium single-particle energy gap, CDW is enhanced and SC is suppressed, while this behavior is reversed for blue detuning. Both orders oscillate with an emergent slow frequency, which is controlled by the small amplitude of a third induced order, namely η pairing, given by the commutator of the two primary orders. The induced η pairing is shown to control the enhancement and suppression of the dominant orders. Finally, we demonstrate that light-induced superconductivity is possible starting from a predominantly CDW initial state.

  1. Quantum thermodynamic processes: a control theory for machine cycles

    NASA Astrophysics Data System (ADS)

    Birjukov, J.; Jahnke, T.; Mahler, G.

    2008-07-01

    The minimal set of thermodynamic control parameters consists of a statistical (thermal) and a mechanical one. These suffice to introduce all the pertinent thermodynamic variables; thermodynamic processes can then be defined as paths on this 2-dimensional control plane. Putting aside coherence we show that for a large class of quantum objects with discrete spectra and for the cycles considered the Carnot efficiency applies as a universal upper bound. In the dynamic (finite time) regime renormalized thermodynamic variables allow to include non-equilibrium phenomena in a systematic way. The machine function ceases to exist in the large speed limit; the way, in which this limit is reached, depends on the type of cycle considered.

  2. Theory and application of semiochemicals in nuisance fish control

    USGS Publications Warehouse

    Sorensen, Peter W.; Johnson, Nicholas

    2016-01-01

    Controlling unwanted, or nuisance, fishes is becoming an increasingly urgent issue with few obvious solutions. Because fish rely heavily on semiochemicals, or chemical compounds that convey information between and within species, to mediate aspects of their life histories, these compounds are increasingly being considered as an option to help control wild fish. Possible uses of semiochemicals include measuring their presence in water to estimate population size, adding them to traps to count or remove specific species of fish, adding them to waterways to manipulate large-scale movement patterns, and saturating the environment with synthesized semiochemicals to disrupt responses to the natural cue. These applications may be especially appropriate for pheromones, chemical signals that pass between members of same species and which also have extreme specificity and potency. Alarm cues, compounds released by injured fish, and cues released by potential predators also could function as repellents and be especially useful if paired with pheromonal attractants in “push-pull” configurations. Approximately half a dozen attractive pheromones now have been partially identified in fish, and those for the sea lamprey and the common carp have been tested in the field with modest success. Alarm and predator cues for sea lamprey also have been tested in the laboratory and field with some success. Success has been hampered by our incomplete understanding of chemical identity, a lack of synthesized compounds, the fact that laboratory bioassays do not always reflect natural environments, and the relative difficulty of conducting trials on wild fishes because of short field seasons and regulatory requirements. Nevertheless, workers continue efforts to identify pheromones because of the great potential elucidated by insect control and the fact that few tools are available to control nuisance fish. Approaches developed for nuisance fish also could be applied to valued fishes, which

  3. Organizational Systems Theory and Command and Control Concepts

    DTIC Science & Technology

    2013-03-01

    controlled assembly line is instead carefully crafted by artist-mechanics who loosely follow schedules and procedures to create a one-of-a-kind machine...history illustrates how some armies planned and executed operations to the smallest detail (Detailed Command) while other armies allowed commanders...Mission Command. Studying C2 concepts in history illustrates how some armies planned and executed operations to the smallest detail (Detailed

  4. Organizational Friction: Urban Crime Control Diminish Effect Theory

    DTIC Science & Technology

    2010-12-10

    Belize” by social violence anthropologist Dr. Herbert Gayle and Nelma Mortis along with Jamuna Vasquez ; Raymond J. Mossiah, Melvin Hewlett, and Alindy...analysis New Jersey: Prentice-Hall Inc. Gayle, Herbert, and Nelma Mortis, with Jamuna Vasquez , Raymond Mossiah, Melvin Hewlett, Alindy Amaya. 2010. Male...Longman Inc. 125 News 5. 2010. Crime control council looks at rogue cops and Crooks report. Michael Young interview by Jose Sanchez . 12 March

  5. Theory and Application of Semiochemicals in Nuisance Fish Control.

    PubMed

    Sorensen, Peter W; Johnson, Nicholas S

    2016-07-01

    Controlling unwanted, or nuisance, fishes is becoming an increasingly urgent issue with few obvious solutions. Because fish rely heavily on semiochemicals, or chemical compounds that convey information between and within species, to mediate aspects of their life histories, these compounds are increasingly being considered as an option to help control wild fish. Possible uses of semiochemicals include measuring their presence in water to estimate population size, adding them to traps to count or remove specific species of fish, adding them to waterways to manipulate large-scale movement patterns, and saturating the environment with synthesized semiochemicals to disrupt responses to the natural cue. These applications may be especially appropriate for pheromones, chemical signals that pass between members of same species and which also have extreme specificity and potency. Alarm cues, compounds released by injured fish, and cues released by potential predators also could function as repellents and be especially useful if paired with pheromonal attractants in "push-pull" configurations. Approximately half a dozen attractive pheromones now have been partially identified in fish, and those for the sea lamprey and the common carp have been tested in the field with modest success. Alarm and predator cues for sea lamprey also have been tested in the laboratory and field with some success. Success has been hampered by our incomplete understanding of chemical identity, a lack of synthesized compounds, the fact that laboratory bioassays do not always reflect natural environments, and the relative difficulty of conducting trials on wild fishes because of short field seasons and regulatory requirements. Nevertheless, workers continue efforts to identify pheromones because of the great potential elucidated by insect control and the fact that few tools are available to control nuisance fish. Approaches developed for nuisance fish also could be applied to valued fishes, which

  6. The use of "stabilization exercises" to affect neuromuscular control in the lumbopelvic region: a narrative review.

    PubMed

    Bruno, Paul

    2014-06-01

    It is well-established that the coordination of muscular activity in the lumbopelvic region is vital to the generation of mechanical spinal stability. Several models illustrating mechanisms by which dysfunctional neuromuscular control strategies may serve as a cause and/or effect of low back pain have been described in the literature. The term "core stability" is variously used by clinicians and researchers, and this variety has led to several rehabilitative approaches suggested to affect the neuromuscular control strategies of the lumbopelvic region (e.g. "stabilization exercise", "motor control exercise"). This narrative review will highlight: 1) the ongoing debate in the clinical and research communities regarding the terms "core stability" and "stabilization exercise", 2) the importance of sub-grouping in identifying those patients most likely to benefit from such therapeutic interventions, and 3) two protocols that can assist clinicians in this process.

  7. Cognitive-affective neural plasticity following active-controlled mindfulness intervention

    PubMed Central

    Allen, Micah; Dietz, Martin; Blair, Karina S.; van Beek, Martijn; Rees, Geraint; Vestergaard-Poulsen, Peter; Lutz, Antoine; Roepstorff, Andreas

    2015-01-01

    Mindfulness meditation is a set of attention-based, regulatory and self-inquiry training regimes. Although the impact of mindfulness meditation training (MT) on self-regulation is well established, the neural mechanisms supporting such plasticity are poorly understood. MT is thought to act on attention through interoceptive salience and attentional control mechanisms, but until now conflicting evidence from behavioral and neural measures has made it difficult to distinguish the role of these mechanisms. To resolve this question we conducted a fully randomized 6-week longitudinal trial of MT, explicitly controlling for cognitive and treatment effects with an active control group. We measured behavioral metacognition and whole-brain Blood Oxygenation Level Dependent (BOLD) signals using functional MRI during an affective Stroop task before and after intervention. Although both groups improved significantly on a response-inhibition task, only the MT group showed reduced affective Stroop conflict. Moreover, the MT group displayed greater dorsolateral prefrontal cortex (DLPFC) responses during executive processing, consistent with increased recruitment of top-down mechanisms to resolve conflict. In contrast, we did not observe overall group by time interactions on negative affect-related RTs or BOLD responses. However, only participants with the greatest amount of MT practice showed improvements in response-inhibition and increased recruitment of dorsal anterior cingulate cortex (dACC), medial prefrontal cortex (mPFC), and right anterior insula during negative valence processing. Collectively our findings highlight the importance of active control in MT research, and indicate unique neural mechanisms for progressive stages of mindfulness training. PMID:23115195

  8. Cognitive-affective neural plasticity following active-controlled mindfulness intervention.

    PubMed

    Allen, Micah; Dietz, Martin; Blair, Karina S; van Beek, Martijn; Rees, Geraint; Vestergaard-Poulsen, Peter; Lutz, Antoine; Roepstorff, Andreas

    2012-10-31

    Mindfulness meditation is a set of attention-based, regulatory, and self-inquiry training regimes. Although the impact of mindfulness training (MT) on self-regulation is well established, the neural mechanisms supporting such plasticity are poorly understood. MT is thought to act through interoceptive salience and attentional control mechanisms, but until now conflicting evidence from behavioral and neural measures renders difficult distinguishing their respective roles. To resolve this question we conducted a fully randomized 6 week longitudinal trial of MT, explicitly controlling for cognitive and treatment effects with an active-control group. We measured behavioral metacognition and whole-brain blood oxygenation level-dependent (BOLD) signals using functional MRI during an affective Stroop task before and after intervention in healthy human subjects. Although both groups improved significantly on a response-inhibition task, only the MT group showed reduced affective Stroop conflict. Moreover, the MT group displayed greater dorsolateral prefrontal cortex responses during executive processing, consistent with increased recruitment of top-down mechanisms to resolve conflict. In contrast, we did not observe overall group-by-time interactions on negative affect-related reaction times or BOLD responses. However, only participants with the greatest amount of MT practice showed improvements in response inhibition and increased recruitment of dorsal anterior cingulate cortex, medial prefrontal cortex, and right anterior insula during negative valence processing. Our findings highlight the importance of active control in MT research, indicate unique neural mechanisms for progressive stages of mindfulness training, and suggest that optimal application of MT may differ depending on context, contrary to a one-size-fits-all approach.

  9. A Theory of Rate Coding Control by Intrinsic Plasticity Effects

    PubMed Central

    Naudé, J.; Paz, J. T.; Berry, H.; Delord, B.

    2012-01-01

    , the present theory is also relevant to other neural processes involving excitability changes, such as neuromodulation, development, aging and neural disorders. PMID:22275858

  10. Applications of nonlinear systems theory to control design

    NASA Technical Reports Server (NTRS)

    Hunt, L. R.; Villarreal, Ramiro

    1988-01-01

    For most applications in the control area, the standard practice is to approximate a nonlinear mathematical model by a linear system. Since the feedback linearizable systems contain linear systems as a subclass, the procedure of approximating a nonlinear system by a feedback linearizable one is examined. Because many physical plants (e.g., aircraft at the NASA Ames Research Center) have mathematical models which are close to feedback linearizable systems, such approximations are certainly justified. Results and techniques are introduced for measuring the gap between the model and its truncated linearizable part. The topic of pure feedback systems is important to the study.

  11. Cartesian theories on the passions, the pineal gland and the pathogenesis of affective disorders: an early forerunner.

    PubMed

    López-Muñoz, F; Alamo, C

    2011-03-01

    The relationship between physical and functional alterations in the pineal gland, the 'passions' (emotions or feelings) and psychopathology has been a constant throughout the history of medicine. One of the most influential authors on this subject was René Descartes, who discussed it in his work The Treatise on the Passions of the Soul (1649). Descartes believed that 'passions' were sensitive movements that the soul, located in the pineal gland, experienced due to its union with the body, by circulating animal spirits. Descartes described sadness as one of the six primitive passions of the soul, which leads to melancholy if not remedied. Cartesian theories had a great deal of influence on the way that mental pathologies were considered throughout the entire 17th century and during much of the 18th century, but the link between the pineal gland and psychiatric disorders it was definitively highlighted in the 20th century, with the discovery of melatonin in 1958. The recent development of a new pharmacological agent acting through melatonergic receptors (agomelatine) has confirmed the close link between the pineal gland and affective disorders.

  12. Income under female versus male control: hypotheses from a theory of gender stratification and data from the Third World.

    PubMed

    Blumberg, R L

    1988-03-01

    This article presents a summary of Blumberg's general theory of gender stratification, which emphasizes relative male/female control of economic resources as a main (although not sole) predictor of a broad array of gender stratification consequences. It also reviews evidence from numerous Third World countries that men and women spend income under their control differently--with women holding back less for themselves and spending more on child nutrition and family basic human needs. Thus the data indicate that when women lose control of income, what is affected is not only their relative marital/familial power (and self-esteem) but also family well-being. Moreover, evidence is presented that planned Third World development projects that rely on female labor but do not provide women with a return to that labor also are likely to suffer: women will attempt to reallocate their efforts to tasks yielding income under their own control. In Africa, where women raise most locally marketed/consumed food and usually have specific familial obligations that require them to have independently controlled income, the bypassing of women farmers and undercutting their returns may be an important--albeit unheralded--factor in the region's food crisis. In sum, the Third World data support both the theory of gender stratification and the relative resources approach to marital power, and point the way to broadening the US marital/family power debate to include male/female spending patterns.

  13. Adaptive Neuro-Fuzzy Control of a Spherical Rolling Robot Using Sliding-Mode-Control-Theory-Based Online Learning Algorithm.

    PubMed

    Kayacan, Erkan; Kayacan, Erdal; Ramon, Herman; Saeys, Wouter

    2013-02-01

    As a model is only an abstraction of the real system, unmodeled dynamics, parameter variations, and disturbances can result in poor performance of a conventional controller based on this model. In such cases, a conventional controller cannot remain well tuned. This paper presents the control of a spherical rolling robot by using an adaptive neuro-fuzzy controller in combination with a sliding-mode control (SMC)-theory-based learning algorithm. The proposed control structure consists of a neuro-fuzzy network and a conventional controller which is used to guarantee the asymptotic stability of the system in a compact space. The parameter updating rules of the neuro-fuzzy system using SMC theory are derived, and the stability of the learning is proven using a Lyapunov function. The simulation results show that the control scheme with the proposed SMC-theory-based learning algorithm is able to not only eliminate the steady-state error but also improve the transient response performance of the spherical rolling robot without knowing its dynamic equations.

  14. A Behavioral Intervention for War-Affected Youth in Sierra Leone: A Randomized Controlled Trial

    PubMed Central

    Betancourt, Theresa S.; McBain, Ryan; Newnham, Elizabeth A.; Akinsulure-Smith, Adeyinka M.; Brennan, Robert T.; Weisz, John R.; Hansen, Nathan B.

    2016-01-01

    Objective Youth in war-affected regions are at risk for poor psychological, social, and educational outcomes. Effective interventions are needed to improve mental health, social behavior, and school functioning. This randomized controlled trial tested the effectiveness of a 10-session cognitive-behavioral therapy (CBT)–based group mental health intervention for multisymptomatic war-affected youth (aged 15–24 years) in Sierra Leone. Method War-affected youth identified by elevated distress and impairment via community screening were randomized (stratified by sex and age) to the Youth Readiness Intervention (YRI) (n = 222) or to a control condition (n = 214). After treatment, youth were again randomized and offered an education subsidy immediately (n = 220) or waitlisted (n = 216). Emotion regulation, psychological distress, prosocial attitudes/behaviors, social support, functional impairment, and posttraumatic stress disorder (PTSD) symptoms were assessed at pre- and postintervention and at 6-month follow-up. For youth in school, enrollment, attendance, and classroom performance were assessed after 8 months. Linear mixed-effects regressions evaluated outcomes. Results The YRI showed significant postintervention effects on emotion regulation, prosocial attitudes/behaviors, social support, and reduced functional impairment, and significant follow-up effects on school enrollment, school attendance, and classroom behavior. In contrast, education subsidy was associated with better attendance but had no effect on mental health or functioning, school retention, or classroom behavior. Interactions between education subsidy and YRI were not significant. Conclusion YRI produced acute improvements in mental health and functioning as well as longer-term effects on school engagement and behavior, suggesting potential to prepare war-affected youth for educational and other opportunities. Clinical trial registration information-Trial of the Youth Readiness Intervention (YRI

  15. Controlling Retrieval during Practice: Implications for Memory-Based Theories of Automaticity

    ERIC Educational Resources Information Center

    Wilkins, Nicolas J.; Rawson, Katherine A.

    2011-01-01

    Memory-based processing theories of automaticity assume that shifts from algorithmic to retrieval-based processing underlie practice effects on response times. The current work examined the extent to which individuals can exert control over the involvement of retrieval during skill acquisition and the factors that may influence control. In two…

  16. Sex and Self-Control Theory: The Measures and Causal Model May Be Different

    ERIC Educational Resources Information Center

    Higgins, George E.; Tewksbury, Richard

    2006-01-01

    This study examines the distribution differences across sexes in key measures of self-control theory and differences in a causal model. Using cross-sectional data from juveniles ("n" = 1,500), the study shows mean-level differences in many of the self-control, risky behavior, and delinquency measures. Structural equation modeling…

  17. Advanced Quality Control Theory for Training and Education: A Guide to Optimizing Training and Education Efforts

    ERIC Educational Resources Information Center

    Heppler, Brad

    2008-01-01

    This is a book about quality and how to control quality through deliberate actions on the part of the professionals developing and implementing the instances of instruction available at an organization. Quality control theory favors no particular learning philosophy and is only directed towards aspects of how, what, where and when measurements are…

  18. Rough-Wall Channel Analysis Using Suboptimal Control Theory

    NASA Technical Reports Server (NTRS)

    Flores, O.; Jimenez, J.; Tenpleton, J.

    2003-01-01

    The original aim of this work was to shed some light on the physics of turbulence over rough walls using large-eddy simulations and the suboptimal-control wall boundary conditions introduced by Nicoud et al. It was hoped that, if that algorithm was used to fit the mean velocity profile of the simulations to that of a rough-walled channel, instead of to a smooth one, the wall stresses introduced by the control algorithm would give some indication of what aspects of rough walls are most responsible for the modification of the flow in real turbulence. It was similarly expected that the structure of the resulting velocity fluctuations would share some of the characteristics of rough-walled flows, thus again suggesting what is intrinsic and what is accidental in the effect of geometric wall roughness. A secondary goal was to study the effect of 'unphysical' boundary conditions on the outside flow by observing how a relatively major change of the target velocity profile, and therefore presumably of the applied wall stresses, modifies properties such as the dominant length scales of the velocity fluctuations away from the wall. As will be seen below, this secondary goal grew more important during the course of the study, which was carried out during a short summer visit of the first two authors to the CTR. It became clear that there are open questions about the way in which the control algorithm models the boundary conditions, even for smooth walls, and that these questions make the physical interpretation of the results difficult. Considerable more work in that area seems to be needed before even relatively advanced large-eddy simulations, such as these, can be used to draw conclusions about the physics of wall-bounded turbulent flows. The numerical method is the same as in Nicoud et al. The modifications introduced in the original code are briefly described in section 2, but the original paper should be consulted for a full description of the algorithm. The results are

  19. Kalman meets neuron: the emerging intersection of control theory with neuroscience.

    PubMed

    Schiff, Steven J

    2009-01-01

    Since the 1950s, we have developed mature theories of modern control theory and computational neuroscience with almost no interaction between these disciplines. With the advent of computationally efficient nonlinear Kalman filtering techniques, along with improved neuroscience models that provide increasingly accurate reconstruction of dynamics in a variety of important normal and disease states in the brain, the prospects for a synergistic interaction between these fields are now strong. I show recent examples of the use of nonlinear control theory for the assimilation and control of single neuron dynamics, the modulation of oscillatory wave dynamics in brain cortex, a control framework for Parkinsonian dynamics and seizures, and the use of optimized parameter model networks to assimilate complex network data - the 'consensus set'.

  20. Aircraft ride quality controller design using new robust root clustering theory for linear uncertain systems

    NASA Technical Reports Server (NTRS)

    Yedavalli, R. K.

    1992-01-01

    The aspect of controller design for improving the ride quality of aircraft in terms of damping ratio and natural frequency specifications on the short period dynamics is addressed. The controller is designed to be robust with respect to uncertainties in the real parameters of the control design model such as uncertainties in the dimensional stability derivatives, imperfections in actuator/sensor locations and possibly variations in flight conditions, etc. The design is based on a new robust root clustering theory developed by the author by extending the nominal root clustering theory of Gutman and Jury to perturbed matrices. The proposed methodology allows to get an explicit relationship between the parameters of the root clustering region and the uncertainty radius of the parameter space. The current literature available for robust stability becomes a special case of this unified theory. The bounds derived on the parameter perturbation for robust root clustering are then used in selecting the robust controller.

  1. A comparison of design variables for control theory based airfoil optimization

    NASA Technical Reports Server (NTRS)

    Reuther, James; Jameson, Antony

    1995-01-01

    This paper describes the implementation of optimization techniques based on control theory for airfoil design. In our previous work in the area it was shown that control theory could be employed to devise effective optimization procedures for two-dimensional profiles by using either the potential flow or the Euler equations with either a conformal mapping or a general coordinate system. We have also explored three-dimensional extensions of these formulations recently. The goal of our present work is to demonstrate the versatility of the control theory approach by designing airfoils using both Hicks-Henne functions and B-spline control points as design variables. The research also demonstrates that the parameterization of the design space is an open question in aerodynamic design.

  2. Radiative Transfer Theory Verified by Controlled Laboratory Experiments

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.; Goldstein, Dennis H.; Chowdhary, Jacek; Lompado, Arthur

    2013-01-01

    We report the results of high-accuracy controlled laboratory measurements of the Stokes reflection matrix for suspensions of submicrometer-sized latex particles in water and compare them with the results of a numerically exact computer solution of the vector radiative transfer equation (VRTE). The quantitative performance of the VRTE is monitored by increasing the volume packing density of the latex particles from 2 to 10. Our results indicate that the VRTE can be applied safely to random particulate media with packing densities up to 2. VRTE results for packing densities of the order of 5 should be taken with caution, whereas the polarized bidirectional reflectivity of suspensions with larger packing densities cannot be accurately predicted. We demonstrate that a simple modification of the phase matrix entering the VRTE based on the so-called static structure factor can be a promising remedy that deserves further examination.

  3. "Pedagogy, Identity and the Construction of a Theory of Symbolic Control": Basil Bernstein Questioned by Joseph Solomon.

    ERIC Educational Resources Information Center

    Bernstein, Basil; Solomon, Joseph

    1999-01-01

    Provides background information on Basil Bernstein and his theory of symbolic control and cultural production. Presents an interview with Bernstein addressing such topics as the concept of "pedagogy" and its role in his theory, "boundaries" as a conceptual key in his theory, and transformation of his theory. (CMK)

  4. Theory of ultrafast nonresonant multiphoton transitions in polyatomic molecules: Basics and application to optimal control theory

    SciTech Connect

    May, Volkhard; Ambrosek, David; Oppel, Markus; Gonzalez, Leticia

    2007-10-14

    A systematic approach is presented to describe nonresonant multiphoton transitions, i.e., transitions between two electronic states without the presence of additional intermediate states resonant with the single-photon energy. The method is well suited to describe femtosecond spectroscopic experiments and, in particular, attempts to achieve laser pulse control of molecular dynamics. The obtained effective time-dependent Schroedinger equation includes effective couplings to the radiation field which combine powers of the field strength and effective transition dipole operators between the initial and final states. To arrive at time-local equations our derivation combines the well-known rotating wave approximation with the approximation of slowly varying amplitudes. Under these terms, the optimal control formalism can be readily extended to also account for nonresonant multiphoton events. Exemplary, nonresonant two- and three-photon processes, similar to those occurring in the recent femtosecond pulse-shaping experiments on CpMn(CO){sub 3}, are treated using related ab initio potential energy surfaces.

  5. Cognitive reappraisal and secondary control coping: associations with working memory, positive and negative affect, and symptoms of anxiety/depression.

    PubMed

    Andreotti, Charissa; Thigpen, Jennifer E; Dunn, Madeleine J; Watson, Kelly; Potts, Jennifer; Reising, Michelle M; Robinson, Kristen E; Rodriguez, Erin M; Roubinov, Danielle; Luecken, Linda; Compas, Bruce E

    2013-01-01

    The current study examined the relations of measures of cognitive reappraisal and secondary control coping with working memory abilities, positive and negative affect, and symptoms of anxiety and depression in young adults (N=124). Results indicate significant relations between working memory abilities and reports of secondary control coping and between reports of secondary control coping and cognitive reappraisal. Associations were also found between measures of secondary control coping and cognitive reappraisal and positive and negative affect and symptoms of depression and anxiety. Further, the findings suggest that reports of cognitive reappraisal may be more strongly predictive of positive affect whereas secondary control coping may be more strongly predictive of negative affect and symptoms of depression and anxiety. Overall, the results suggest that current measures of secondary control coping and cognitive reappraisal capture related but distinct constructs and suggest that the assessment of working memory may be more strongly related to secondary control coping in predicting individual differences in distress.

  6. [Application of damage control theory on the trauma orthopaedic treatment].

    PubMed

    Wang, Jing-bo; Jin, Hong-bin

    2009-07-01

    The treatment of severely traumatic patients was changing from total care treament to the damage control surgery, as a result in the inflammatory reaction caused by trauma, in which the inflammatory marks, such as interleukin-6 and serum procalcitonin in the blood increased, and caused hypothermia, acidosis, and disturbance of blood coagulation, and resulted in the acute respiratory distress syndrome and multiple organs failure. A long-term operation as the second hit made the disease worse. In the patients, the femoral fracture was treated with external fixator; the pelvic fracture was treated with external fixator, and the uncontrolled haemorrhage in the pelvis was treated through direct hemostasis, angiography and embolism of arteries, and the tamponade of pelvis; the purpose of treatment of spinal fracture was keeping the stability of spine, avoiding the secondary injury on the spinal cord. It must pay attention to the injury of the adjacent organs and infection in the opening spinal injury. The result of operation was better in the incomplete spinal cord injury.

  7. Natural control of bacteria affecting meat quality by a neem (Azadirachta indica A. Juss) cake extract.

    PubMed

    Del Serrone, P; Failla, S; Nicoletti, M

    2015-01-01

    The antibacterial activity of an ethylacetate neem cake extract (NCE) against bacteria that affect meat quality, namely Campylobacter jejuni, Carnobacterium spp., Lactobacillus curvatus, Lactobacillus sakei and Leuconostoc sp., is reported. The antibacterial activity was detected using standardised disc diffusion and macrodilution methods. The bacterial growth inhibition zone ranged from 11.33 ± 0.58 to 22.67 ± 0.58 mm (100 μL NCE). There is significant difference between the growth inhibition zone of NCE and the control (ciprofloxacin 100 μg). The percent of bacterial growth reduction range was 79.75 ± 1.53 to 90.73 ± 1.53 (100 μg NCE) as compared with control (without NCE). NCE in different amounts counteracted the growth of all tested bacteria.

  8. Anti-disturbance control theory for systems with multiple disturbances: a survey.

    PubMed

    Guo, Lei; Cao, Songyin

    2014-07-01

    The problem of anti-disturbance control has been an eternal topic along with the development of the control theory. However, most methodologies can only deal with systems subject to a single equivalent disturbance which was merged by various types of uncertainties. In this paper, a review on anti-disturbance control is presented for systems with multiple disturbances. First, the classical control methods are briefly reviewed for disturbance attenuation or rejection problems. Then, recent advances in disturbance observer based control (DOBC) theory are introduced and especially, the composite hierarchical anti-disturbance control (CHADC) is firstly addressed. A comparison of different approaches is briefly carried out. Finally, focuses in the field on the current research are also addressed with emphasis on the practical application of the techniques.

  9. Vibration and control of a flexible rotor in magnetic bearings using hybrid method and H{sup {infinity}} control theory

    SciTech Connect

    Shiau, T.N.; Sheu, G.J.; Yang, C.D.

    1997-01-01

    The vibration and active control of a flexible rotor system with magnetic bearings are investigated using Hybrid Method (HM) and H{sup {infinity}} control theory with consideration of gyroscopic effect. The hybrid method, which combines the merits of the finite element method (FEM) and generalized polynomial expansion method (GPEM) is employed to model the flexible rotor system with small order of plant. The mixed sensitivity problem of H{sup {infinity}} control theory is applied to design the control of system vibration with spillover phenomena for the reduced order plant. The H{sub 2} control design is also employed for comparison with the H{sup {infinity}} design. The experimental simulation is used to illustrate the effects of control design. It is shown that the H{sup {infinity}} controller design can be very effective to suppress spillover phenomena. In addition, the H{sup {infinity}} control design has robustness to the variation of the model parameters. The application of the hybrid method (HM) together with H{sup {infinity}} control design is highly recommended for vibration control of flexible rotor systems with magnetic bearings.

  10. Gender, Race, and Delinquent Behavior: An Extension of Power-Control Theory to American Indian Adolescents.

    PubMed

    Eitle, David; Niedrist, Fallon; Eitle, Tamela McNulty

    2014-01-01

    Research testing Hagan's power-control theory has largely been tested with samples of non-Hispanic whites. We extend prior research by testing the theory's merits with a sample of American Indian (AI) adolescents. Overall, we find mixed support for the theory's merits. However, we find that our measure of patriarchy is a robust predictor of AI female delinquent activity. We also find that a grandparent in the household serves to greatly reduce involvement in violent behavior among AI females. Compared to a sample of non-Hispanic whites, these results reveal the importance of testing explanations of deviant behavior across racial and ethnic groups.

  11. Auxiliary matrix formalism for interaction representation transformations, optimal control, and spin relaxation theories.

    PubMed

    Goodwin, D L; Kuprov, Ilya

    2015-08-28

    Auxiliary matrix exponential method is used to derive simple and numerically efficient general expressions for the following, historically rather cumbersome, and hard to compute, theoretical methods: (1) average Hamiltonian theory following interaction representation transformations; (2) Bloch-Redfield-Wangsness theory of nuclear and electron relaxation; (3) gradient ascent pulse engineering version of quantum optimal control theory. In the context of spin dynamics, the auxiliary matrix exponential method is more efficient than methods based on matrix factorizations and also exhibits more favourable complexity scaling with the dimension of the Hamiltonian matrix.

  12. Auxiliary matrix formalism for interaction representation transformations, optimal control, and spin relaxation theories

    SciTech Connect

    Goodwin, D. L.; Kuprov, Ilya

    2015-08-28

    Auxiliary matrix exponential method is used to derive simple and numerically efficient general expressions for the following, historically rather cumbersome, and hard to compute, theoretical methods: (1) average Hamiltonian theory following interaction representation transformations; (2) Bloch-Redfield-Wangsness theory of nuclear and electron relaxation; (3) gradient ascent pulse engineering version of quantum optimal control theory. In the context of spin dynamics, the auxiliary matrix exponential method is more efficient than methods based on matrix factorizations and also exhibits more favourable complexity scaling with the dimension of the Hamiltonian matrix.

  13. Mastoid vibration affects dynamic postural control during gait in healthy older adults

    PubMed Central

    Chien, Jung Hung; Mukherjee, Mukul; Kent, Jenny; Stergiou, Nicholas

    2017-01-01

    Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration. PMID:28128341

  14. Mastoid vibration affects dynamic postural control during gait in healthy older adults

    NASA Astrophysics Data System (ADS)

    Chien, Jung Hung; Mukherjee, Mukul; Kent, Jenny; Stergiou, Nicholas

    2017-01-01

    Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration.

  15. Virtual Reality for Enhanced Ecological Validity and Experimental Control in the Clinical, Affective and Social Neurosciences

    PubMed Central

    Parsons, Thomas D.

    2015-01-01

    An essential tension can be found between researchers interested in ecological validity and those concerned with maintaining experimental control. Research in the human neurosciences often involves the use of simple and static stimuli lacking many of the potentially important aspects of real world activities and interactions. While this research is valuable, there is a growing interest in the human neurosciences to use cues about target states in the real world via multimodal scenarios that involve visual, semantic, and prosodic information. These scenarios should include dynamic stimuli presented concurrently or serially in a manner that allows researchers to assess the integrative processes carried out by perceivers over time. Furthermore, there is growing interest in contextually embedded stimuli that can constrain participant interpretations of cues about a target’s internal states. Virtual reality environments proffer assessment paradigms that combine the experimental control of laboratory measures with emotionally engaging background narratives to enhance affective experience and social interactions. The present review highlights the potential of virtual reality environments for enhanced ecological validity in the clinical, affective, and social neurosciences. PMID:26696869

  16. Affect-focused psychodynamic psychotherapy for depression and anxiety through the Internet: a randomized controlled trial

    PubMed Central

    Björklund, Martin; Hornborg, Christoffer; Karlsson, Stina; Hesser, Hugo; Ljótsson, Brjánn; Rousseau, Andréas; Frederick, Ronald J.; Andersson, Gerhard

    2013-01-01

    Background. Psychodynamic psychotherapy is a psychological treatment approach that has a growing empirical base. Research has indicated an association between therapist-facilitated affective experience and outcome in psychodynamic therapy. Affect-phobia therapy (APT), as outlined by McCullough et al., is a psychodynamic treatment that emphasizes a strong focus on expression and experience of affect. This model has neither been evaluated for depression nor anxiety disorders in a randomized controlled trial. While Internet-delivered psychodynamic treatments for depression and generalized anxiety disorder exist, they have not been based on APT. The aim of this randomized controlled trial was to investigate the efficacy of an Internet-based, psychodynamic, guided self-help treatment based on APT for depression and anxiety disorders. Methods. One hundred participants with diagnoses of mood and anxiety disorders participated in a randomized (1:1 ratio) controlled trial of an active group versus a control condition. The treatment group received a 10-week, psychodynamic, guided self-help treatment based on APT that was delivered through the Internet. The treatment consisted of eight text-based treatment modules and included therapist contact (9.5 min per client and week, on average) in a secure online environment. Participants in the control group also received online therapist support and clinical monitoring of symptoms, but received no treatment modules. Outcome measures were the 9-item Patient Health Questionnaire Depression Scale (PHQ-9) and the 7-item Generalized Anxiety Disorder Scale (GAD-7). Process measures were also included. All measures were administered weekly during the treatment period and at a 7-month follow-up. Results. Mixed models analyses using the full intention-to-treat sample revealed significant interaction effects of group and time on all outcome measures, when comparing treatment to the control group. A large between-group effect size of Cohen

  17. Antecedent acute cycling exercise affects attention control: an ERP study using attention network test.

    PubMed

    Chang, Yu-Kai; Pesce, Caterina; Chiang, Yi-Te; Kuo, Cheng-Yuh; Fong, Dong-Yang

    2015-01-01

    The purpose of this study was to investigate the after-effects of an acute bout of moderate intensity aerobic cycling exercise on neuroelectric and behavioral indices of efficiency of three attentional networks: alerting, orienting, and executive (conflict) control. Thirty young, highly fit amateur basketball players performed a multifunctional attentional reaction time task, the attention network test (ANT), with a two-group randomized experimental design after an acute bout of moderate intensity spinning wheel exercise or without antecedent exercise. The ANT combined warning signals prior to targets, spatial cueing of potential target locations and target stimuli surrounded by congruent or incongruent flankers, which were provided to assess three attentional networks. Event-related brain potentials and task performance were measured during the ANT. Exercise resulted in a larger P3 amplitude in the alerting and executive control subtasks across frontal, central and parietal midline sites that was paralleled by an enhanced reaction speed only on trials with incongruent flankers of the executive control network. The P3 latency and response accuracy were not affected by exercise. These findings suggest that after spinning, more resources are allocated to task-relevant stimuli in tasks that rely on the alerting and executive control networks. However, the improvement in performance was observed in only the executively challenging conflict condition, suggesting that whether the brain resources that are rendered available immediately after acute exercise translate into better attention performance depends on the cognitive task complexity.

  18. Robust control design with real parameter uncertainty using absolute stability theory. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    How, Jonathan P.; Hall, Steven R.

    1993-01-01

    The purpose of this thesis is to investigate an extension of mu theory for robust control design by considering systems with linear and nonlinear real parameter uncertainties. In the process, explicit connections are made between mixed mu and absolute stability theory. In particular, it is shown that the upper bounds for mixed mu are a generalization of results from absolute stability theory. Both state space and frequency domain criteria are developed for several nonlinearities and stability multipliers using the wealth of literature on absolute stability theory and the concepts of supply rates and storage functions. The state space conditions are expressed in terms of Riccati equations and parameter-dependent Lyapunov functions. For controller synthesis, these stability conditions are used to form an overbound of the H2 performance objective. A geometric interpretation of the equivalent frequency domain criteria in terms of off-axis circles clarifies the important role of the multiplier and shows that both the magnitude and phase of the uncertainty are considered. A numerical algorithm is developed to design robust controllers that minimize the bound on an H2 cost functional and satisfy an analysis test based on the Popov stability multiplier. The controller and multiplier coefficients are optimized simultaneously, which avoids the iteration and curve-fitting procedures required by the D-K procedure of mu synthesis. Several benchmark problems and experiments on the Middeck Active Control Experiment at M.I.T. demonstrate that these controllers achieve good robust performance and guaranteed stability bounds.

  19. Strength Training Does Not Affect Vagal-cardiac Control or Cardiovagal Baroreflex Sensitivity in Young Healthy Subjects

    DTIC Science & Technology

    2005-03-01

    ORIGINAL ARTICLE William H. Cooke Æ Jason R. Carter Strength training does not affect vagal– cardiac control or cardiovagal baroreflex sensitivity in...to test the hypothesis that high-intensity strength training in- creases vagal– cardiac control and cardiovagal barore- flex sensitivity. Twenty-two...adaptations to resistance training, our results demonstrate that resistance train- ing does not affect vagal– cardiac control or cardiovagal baroreflex

  20. Stance control is not affected by paresis and reflex hyperexcitability: the case of spastic patients

    PubMed Central

    Nardone, A; Galante, M; Lucas, B; Schieppati, M

    2001-01-01

    OBJECTIVES—Spastic patients were studied to understand whether stance unsteadiness is associated with changes in the control of voluntary force, muscle tone, or reflex excitability, rather than to abnormal posture connected to the motor deficit itself.
METHODS—Twenty four normal subjects, 12 patients affected by amyotrophic lateral sclerosis (ALS), seven by spastic paraparesis, and 14 by hemiparesis were studied. All patients featured various degrees of spasticity and paresis but were free from clinically evident sensory deficits. Body sway during quiet upright stance was assessed through a stabilometric platform under both eyes open (EO) and eyes closed (EC) conditions. The sudden rotation of a supporting platform, in a toe up and toe down direction respectively, evoked short (SLR) and medium latency (MLR) reflex responses to stretch of the soleus or the tibialis anterior (TA) muscle.
RESULTS—No relation was found between clinical findings (tone, muscle strength, tendon reflexes, plantar response, and duration of disease) and body sway. On average, all patient groups exhibited a forward shift of the centre of foot pressure (CFP) with respect to normal subjects; in addition, paraparetic and to a much larger extent hemiparetic patients showed a lateral shift of CFP. Body sway area was significantly increased only in the hemiparetic patients. No relation was found between position of the CFP and sway within any patient group. Soleus SLR was increased in all patients with respect to normal subjects. TA SLR was often seen in both patients with ALS and paraparetic patients, but only rarely in normal subjects and hemiparetic patients. However, no relation was found between amplitude of soleus or TA SLRs and stabilometric variables. The frequency and size of soleus MLR and TA MLR were decreased in all patients. These responses were decreased in size and not modulated by background EMG in the affected leg of hemiparetic patients, suggesting a disturbed control of

  1. Nephrology pre-dialysis care affects the psychological adjustment, not only blood pressure, anemia, and phosphorus control.

    PubMed

    Furusho, Masahide; Kawazu, Minami; Takeda, Kazuhito; Kurachi, Emiko; Nakashima, Takafumi; Sagara, Rikako; Hara, Takashi; Mukai, Hideyuki; Miura, Shuhei; Sugawara, Koji

    2015-10-01

    Several studies have suggested that pre-dialysis care is associated with clinical outcomes. However, little has been reported on the influence of pre-dialysis care on the psychological adjustment to dialysis. The purpose of this study was to evaluate the impact of pre-dialysis care on psychological adjustment to dialysis and clinical characteristics. In this cross-sectional study, we enrolled 52 patients who started hemodialysis at our hospital. They were divided into two groups according to the time of referral to our hospital: the early referral group (over 1 year prior to first dialysis: 19 patients, mean age 69.3 ± 11.1) and the late referral group (within 1 year prior to first dialysis: 33 patients, mean age 72.3 ± 8.9). We measured the clinical characteristics and evaluated the psychological adjustment to dialysis by Shontz's stage theory. Compared with the late referral group, the early referral group had a significantly better clinical characteristics concerning blood pressure (140.2 ± 23.7 vs. 156.9 ± 23.3 mmHg, P = 0.0150), hemoglobin (10.3 ± 1.5 vs. 9.4 ± 1.0 g/dL, P = 0.0078), and phosphorus (4.5 ± 1.5 vs. 5.5 ± 1.3 mg/dL, P = 0.0166). In addition, psychological adjustment to dialysis evaluated by Shontz's stage theory was significantly better in the early referral group (P = 0.017). Our results indicate that nephrology pre-dialysis care affects not only blood pressure, anemia, and phosphorus control but also the psychological adjustment to dialysis.

  2. Anticipatory Modulation of Digit Placement for Grasp Control Is Affected by Parkinson's Disease

    PubMed Central

    Lukos, Jamie R.; Lee, Dongpyo; Poizner, Howard; Santello, Marco

    2010-01-01

    Background Successful object manipulation relies on the ability to form and retrieve sensorimotor memories of digit forces and positions used in previous object lifts. Past studies of patients affected by Parkinson's disease (PD) have revealed that the basal ganglia play a crucial role in the acquisition and/or retrieval of sensorimotor memories for grasp control. Whereas it is known that PD impairs anticipatory control of digit forces during grasp, learning deficits associated with the planning of digit placement have yet to be explored. This question is motivated by recent work in healthy subjects revealing that anticipatory control of digit placement plays a crucial role for successful manipulation. Methodology/Principal Findings We asked ten PD patients off medication and ten age-matched controls to reach, grasp and lift an object whose center of mass (CM) was on the left, right or center. The only task requirement was to minimize object roll during lift. The CM remained the same across consecutive trials (blocked condition) or was altered from trial to trial (random condition). We hypothesized that impairment of the basal ganglia-thalamo-cortical circuits in PD patients would reduce their ability to anticipate digit placement appropriate to the CM location. Consequently, we predicted that PD patients would exhibit similar digit placement in the blocked vs. random conditions and produce larger peak object rolls than that of control subjects. In the blocked condition, PD patients exhibited significantly weaker modulation of fingertip contact points to CM location and larger object roll than controls (p<0.05 and p<0.01, respectively). Nevertheless, both controls and PD patients minimized object roll more in the blocked than in the random condition (p<0.01). Conclusions/Significance Our findings indicate that, even though PD patients may have a residual ability of anticipatory control of digit contact points and forces, they fail to implement a motor plan with the

  3. Emotion Risk-Factor in Patients With Cardiac Diseases: The Role of Cognitive Emotion Regulation Strategies, Positive Affect and Negative Affect (A Case-Control Study)

    PubMed Central

    Bahremand, Mostafa; Alikhani, Mostafa; Zakiei, Ali; Janjani, Parisa; Aghaei, Abbas

    2016-01-01

    Application of psychological interventions is essential in classic treatments for patient with cardiac diseases. The present study compared cognitive emotion regulation strategies, positive affect, and negative affect for cardiac patients with healthy subjects. This study was a case-control study. Fifty subjects were selected using convenient sampling method from cardiac (coronary artery disease) patients presenting in Imam Ali medical center of Kermanshah, Iran in the spring 2013. Fifty subjects accompanied the patients to the medical center, selected as control group, did not have any history of cardiac diseases. For collecting data, the cognitive emotion regulation questionnaire and positive and negative affect scales were used. For data analysis, multivariate analysis of variance (MANOVA) was applied using the SPSS statistical software (ver. 19.0). In all cognitive emotion regulation strategies, there was a significant difference between the two groups. A significant difference was also detected regarding positive affect between the two groups, but no significant difference was found regarding negative affect. We found as a result that, having poor emotion regulation strategies is a risk factor for developing heart diseases. PMID:26234976

  4. Gender and family differences in adolescent's heavy alcohol use: the power-control theory perspective.

    PubMed

    Okulicz-Kozaryn, K

    2010-10-01

    According to the power-control theory, growing independence of adolescent girls, manifest in more prevalent problem behaviors, may be explained by changes in family structure (increasing level of authority gained in the workplace by mothers). To verify this hypothesis, self-report data from Warsaw adolescents (N = 3087, age 14-15 years, 50% boys) were used. Results indicate that parenting practices differ across child gender and structure of parents' work authority. Girls, especially in patriarchal households, spend more time with mothers and perceive stronger maternal control. In egalitarian families, fathers tend to be more involved with sons than with daughters. When parental control, support and adolescents' risk preferences are controlled, the gender-by-household type interaction effect is observed--girls in patriarchal families have the lowest risk of getting drunk. Study results provide support for power-control theory showing the relationship between parental work authority and adolescent's heavy alcohol use.

  5. Musical rhythm and affect. Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

    NASA Astrophysics Data System (ADS)

    Witek, Maria A. G.; Kringelbach, Morten L.; Vuust, Peter

    2015-06-01

    The Quartet Theory of Human Emotion (QT) proposed by Koelsch et al. [1] adds to existing affective models, e.g. by directing more attention to emotional contagion, attachment-related and non-goal-directed emotions. Such an approach seems particularly appropriate to modelling musical emotions, and music is indeed a recurring example in the text, used to illustrate the distinct characteristics of the affect systems that are at the centre of the theory. Yet, it would seem important for any theory of emotion to account for basic functions such as prediction and anticipation, which are only briefly mentioned. Here we propose that QT, specifically its focus on emotional contagion, attachment-related and non-goal directed emotions, might help generate new ideas about a largely neglected source of emotion - rhythm - a musical property that relies fundamentally on the mechanism of prediction.

  6. Wall Models for Large-Eddy Simulation Based on Optimal Control Theory

    DTIC Science & Technology

    2006-06-14

    Optimal Control Theory 5b. GRANT NUMBER F49620-03-1-0132 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Parviz Moin, Principal Investigator...C. THIS ABSTRACT OF PAGES Professor Parviz Moin PAGE 300 20b. TELEPHONE NUMBER (Include area code) 650 723-9713 Standard Form 298 (Rev. 8-98...CONTROL THEORY" PERIOD OF PERFORMANCE: 2/15/2003 - 3/31/2006 by Parviz Moin (PI), Jeremy A. Templeton and Meng Wang Program Manager: Rhett Jefferies

  7. A theory and model of conflict detection in air traffic control: incorporating environmental constraints.

    PubMed

    Loft, Shayne; Bolland, Scott; Humphreys, Michael S; Neal, Andrew

    2009-06-01

    A performance theory for conflict detection in air traffic control is presented that specifies how controllers adapt decisions to compensate for environmental constraints. This theory is then used as a framework for a model that can fit controller intervention decisions. The performance theory proposes that controllers apply safety margins to ensure separation between aircraft. These safety margins are formed through experience and reflect the biasing of decisions to favor safety over accuracy, as well as expectations regarding uncertainty in aircraft trajectory. In 2 experiments, controllers indicated whether they would intervene to ensure separation between pairs of aircraft. The model closely predicted the probability of controller intervention across the geometry of problems and as a function of controller experience. When controller safety margins were manipulated via task instructions, the parameters of the model changed in the predicted direction. The strength of the model over existing and alternative models is that it better captures the uncertainty and decision biases involved in the process of conflict detection. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  8. Barriers and Facilitators Affecting Tuberculosis Infection Control Practices of Russian Health Care Workers

    PubMed Central

    Woith, Wendy Mann; Volchenkov, Grigory; Larson, Janet L.

    2013-01-01

    SUMMARY Setting Five inpatient and outpatient tuberculosis care facilities in two regions of Russia. Objective: To identify barriers and motivators to use of infection control measures among Russian TB health care workers. Design In this qualitative study, a convenience sample of 96 HCWs was used to generate 15 homogeneous focus groups consisting of physicians, nurses, lab staff, or support staff. Results Barriers and motivators related to knowledge, attitudes and beliefs, and practices were identified. Three main barriers were a) knowledge deficits, including the belief that TB was transmitted by dust, linens, and eating utensils; b) negative attitudes related to the discomfort of respirators; and c) practices with respect to quality and care of respirators. Education and training, fear of infecting loved ones, and fear of punishment were the main motivators. Conclusions Our results point to the need for evaluation of current educational programs. Positive health promotion messages that appeal to fear might also be successful in promoting use of TB infection control. Individualized rewards based on personal motivators or group rewards that build on collectivist theory could be explored. PMID:22687261

  9. On Feeling in Control: A Biological Theory for Individual Differences in Control Perception

    ERIC Educational Resources Information Center

    Declerck, Carolyn H.; Boone, Christophe; De Brabander, Bert

    2006-01-01

    This review aims to create a cross-disciplinary framework for understanding the perception of control. Although, the personality trait locus of control, the most common measure of control perception, has traditionally been regarded as a product of social learning, it may have biological antecedents as well. It is suggested that control perception…

  10. Numerical magnitude affects online execution, and not planning of visuomotor control.

    PubMed

    Namdar, Gal; Ganel, Tzvi

    2017-01-20

    Recent literature has established a directional influence of irrelevant numerical magnitude on actions performed toward neutral objects. For example, fingers' aperture during grasping is larger when associated with large compared with small numerical digits. This interaction between symbolic magnitude and visuomotor control has been attributed to the planning stage of the action prior to motor execution. However, this assumption has not been directly tested. In two experiments, we tested whether the effects of numerical magnitude on grasping derive from action planning or from action execution. Participants were asked to grasp an object following a short visual (Experiment 1) or auditory (Experiment 2) presentation of small (1/2) or large (8/9) digits. Grasping was performed under either closed-loop (CL) or open-loop (OL) visuomotor control, for which online vision was prevented during action execution. Digit magnitude affected grip apertures in the CL condition, when online vision was allowed. However, magnitude had no effects on grip aperture in the OL condition. This pattern of results strongly suggests that the processing of numerical magnitude originates from interactions between numerical magnitude and real object size during online motor execution. Unlike previously assumed, the findings also suggest that the effect of magnitude on visuomotor control is not likely to be attributed to the motor planning stage prior to action initiation.

  11. Predicting epistasis: an experimental test of metabolic control theory with bacterial transcription and translation.

    PubMed

    MacLean, R C

    2010-03-01

    Epistatic interactions between mutations are thought to play a crucial role in a number of evolutionary processes, including adaptation and sex. Evidence for epistasis is abundant, but tests of general theoretical models that can predict epistasis are lacking. In this study, I test the ability of metabolic control theory to predict epistasis using a novel experimental approach that combines phenotypic and genetic perturbations of enzymes involved in gene expression and protein synthesis in the bacterium Pseudomonas aeruginosa. These experiments provide experimental support for two key predictions of metabolic control theory: (i) epistasis between genes involved in the same pathway is antagonistic; (ii) epistasis becomes increasingly antagonistic as mutational severity increases. Metabolic control theory is a general theory that applies to any set of genes that are involved in the same linear processing chain, not just metabolic pathways, and I argue that this theory is likely to have important implications for predicting epistasis between functionally coupled genes, such as those involved in antibiotic resistance. Finally, this study highlights the fact that phenotypic manipulations of gene activity provide a powerful method for studying epistasis that complements existing genetic methods.

  12. Aging affects motor skill learning when the task requires inhibitory control.

    PubMed

    Brosseau, Julie; Potvin, Marie-Julie; Rouleau, Isabelle

    2007-01-01

    Few studies have examined the influence of aging on motor skill learning (MSL) tasks involving different skills and conditions. Two tasks, each including two different conditions (repeated and nonrepeated), were used: (a) the Mirror Tracing task, requiring the inhibition of an overlearned response and the learning of a new visuomotor association, and (b) the Pursuit Tracking task, mainly requiring the processing of visuospatial stimuli. We hypothesized that older participants would benefit as much as younger participants from the stimuli repetition and that they would exhibit a slower learning rate exclusively on the Mirror Tracing task. As expected, older and younger participants' MSL were not differentially affected by task conditions. They also showed a similar learning rate on the Pursuit Tracking task and a subgroup of older participants exhibited MSL difficulties on the Mirror Tracing task. Problems in the inhibitory control of competing motor memories could explain these age-related MSL difficulties.

  13. Affective processing in positive schizotypy: Loose control of social-emotional information.

    PubMed

    Papousek, Ilona; Weiss, Elisabeth M; Mosbacher, Jochen A; Reiser, Eva M; Schulter, Günter; Fink, Andreas

    2014-10-30

    Behavioral studies suggested heightened impact of emotionally laden perceptual input in schizophrenia spectrum disorders, in particular in patients with prominent positive symptoms. De-coupling of prefrontal and posterior cortices during stimulus processing, which is related to loosening of control of the prefrontal cortex over incoming affectively laden information, may underlie this abnormality. Pre-selected groups of individuals with low versus high positive schizotypy (lower and upper quartile of a large screening sample) were tested. During exposure to auditory displays of strong emotions (anger, sadness, cheerfulness), individuals with elevated levels of positive schizotypal symptoms showed lesser prefrontal-posterior coupling (EEG coherence) than their symptom-free counterparts (right hemisphere). This applied to negative emotions in particular and was most pronounced during confrontation with anger. The findings indicate a link between positive symptoms and a heightened impact particularly of threatening emotionally laden stimuli which might lead to exacerbation of positive symptoms and inappropriate behavior in interpersonal situations.

  14. The dominant foot affects the postural control mechanism: examination by body tracking test

    PubMed Central

    Ikemiyagi, Fuyuko; Ikemiyagi, Yoshihiro; Tanaka, Tositake; Yamamoto, Masahiko; Suzuki, Mitsuya

    2014-01-01

    Conclusion The antero-posterior (AP) body tracking test (BTT) showed that the dominant foot could affect the tilt angle of the sway movement, delineated by primary component analysis. Differences associated with the dominant foot could represent the difference in space perception of each person. Objectives To examine whether the dominant foot could affect the postural control mechanism using the BTT. Methods Ninety-seven healthy participants enrolled in the study were classified into right-foot and left-foot dominance groups, and their performances were compared. For the BTT, each participant stood on a stabilometer and caught the movement of a visual target moving vertically (anterior-posterior) or horizontally by the center of pressure movement, displayed on a 14-inch screen monitor at 100 cm in front of the subject. The mean displacement angle of the obtained stabilogram was evaluated by principal component analysis. Results The AP BTT in the right-foot dominance group showed a clockwise tilt with a mean displacement angle of 3.022 ± 3.761°, whereas the group with left-foot dominance had a modest counter-clockwise tilt with a mean displacement angle of –0.694 ± 4.497°. This difference was found to be significant by the independent t test (p < 0.0001). In the lateral BTT, the mean displacement angles were not significant. PMID:25252704

  15. Web Intervention for Adolescents Affected by Disaster: Population-Based Randomized Controlled Trial

    PubMed Central

    Ruggiero, Kenneth J.; Price, Matthew; Adams, Zachary; Stauffacher, Kirstin; McCauley, Jenna; Danielson, Carla Kmett; Knapp, Rebecca; Hanson, Rochelle F.; Davidson, Tatiana M.; Amstadter, Ananda B.; Carpenter, Matthew J.; Saunders, Benjamin E.; Kilpatrick, Dean G.; Resnick, Heidi S.

    2015-01-01

    Objective To assess the efficacy of Bounce Back Now (BBN), a modular, web-based intervention for disaster-affected adolescents and their parents. Method A population-based randomized controlled trial used address-based sampling to enroll 2,000 adolescents and parents from communities affected by tornadoes in Joplin, MO, and Alabama. Data collection via baseline and follow-up semi-structured telephone interviews was completed between September 2011 and August 2013. All families were invited to access the BBN study web portal irrespective of mental health status at baseline. Families who accessed the web portal were assigned randomly to 3 groups: (1) BBN, which featured modules for adolescents and parents targeting adolescents’ mental health symptoms; (2) BBN plus additional modules targeting parents’ mental health symptoms; or (3) assessment only. The primary outcomes were adolescent symptoms of posttraumatic stress disorder (PTSD) and depression. Results Nearly 50% of families accessed the web portal. Intent-to-treat analyses revealed time × condition interactions for PTSD symptoms (B=−0.24, SE=0.08, p<.01) and depressive symptoms (B=−0.23, SE=0.09, p<.01). Post-hoc comparisons revealed fewer PTSD and depressive symptoms for adolescents in the experimental vs. control conditions at 12-month follow-up (PTSD: B=−0.36, SE=0.19, p=.06; depressive symptoms: B=−0.42, SE=0.19, p=0.03). A time × condition interaction also was found favoring the BBN vs. BBN + parent self-help condition for PTSD symptoms (B=0.30, SE=0.12, p=.02), but not depressive symptoms (B=0.12, SE=0.12, p=.33). Conclusion Results supported the feasibility and initial efficacy of BBN as a scalable disaster mental health intervention for adolescents. Technology-based solutions have tremendous potential value if found to reduce the mental health burden of disasters. PMID:26299292

  16. Improving the outcomes of children affected by parental substance abuse: a review of randomized controlled trials

    PubMed Central

    Calhoun, Stacy; Conner, Emma; Miller, Melodi; Messina, Nena

    2015-01-01

    Substance abuse is a major public health concern that impacts not just the user but also the user’s family. The effect that parental substance abuse has on children has been given substantial attention over the years. Findings from the literature suggest that children of substance-abusing parents have a high risk of developing physical and mental health and behavioral problems. A number of intervention programs have been developed for parents who have a substance abuse problem. There have also been a number of interventions that have been developed for children who have at least one parent with a substance abuse problem. However, it remains unclear how we can best mitigate the negative effects that parental substance abuse has on children due to the scarcity of evaluations that utilize rigorous methodologies such as experimental designs. The purpose of this study is to review randomized controlled trials of intervention programs targeting parents with substance abuse problems and/or children with at least one parent with a substance abuse problem in order to identify programs that show some promise in improving the behavioral and mental health outcomes of children affected by parental substance abuse. Four randomized controlled trials that met our eligibility criteria were identified using major literature search engines. The findings from this review suggest that interventions that focus on improving parenting practices and family functioning may be effective in reducing problems in children affected by parental substance abuse. However, further research utilizing rigorous methodologies are needed in order to identify other successful interventions that can improve the outcomes of these children long after the intervention has ended. PMID:25670915

  17. Experience Sampling-Based Personalized Feedback and Positive Affect: A Randomized Controlled Trial in Depressed Patients

    PubMed Central

    Hartmann, Jessica A.; Wichers, Marieke; Menne-Lothmann, Claudia; Kramer, Ingrid; Viechtbauer, Wolfgang; Peeters, Frenk; Schruers, Koen R. J.; van Bemmel, Alex L.; Myin-Germeys, Inez; Delespaul, Philippe; van Os, Jim; Simons, Claudia J. P.

    2015-01-01

    Objectives Positive affect (PA) plays a crucial role in the development, course, and recovery of depression. Recently, we showed that a therapeutic application of the experience sampling method (ESM), consisting of feedback focusing on PA in daily life, was associated with a decrease in depressive symptoms. The present study investigated whether the experience of PA increased during the course of this intervention. Design Multicentre parallel randomized controlled trial. An electronic random sequence generator was used to allocate treatments. Settings University, two local mental health care institutions, one local hospital. Participants 102 pharmacologically treated outpatients with a DSM-IV diagnosis of major depressive disorder, randomized over three treatment arms. Intervention Six weeks of ESM self-monitoring combined with weekly PA-focused feedback sessions (experimental group); six weeks of ESM self-monitoring combined with six weekly sessions without feedback (pseudo-experimental group); or treatment as usual (control group). Main outcome The interaction between treatment allocation and time in predicting positive and negative affect (NA) was investigated in multilevel regression models. Results 102 patients were randomized (mean age 48.0, SD 10.2) of which 81 finished the entire study protocol. All 102 patients were included in the analyses. The experimental group did not show a significant larger increase in momentary PA during or shortly after the intervention compared to the pseudo-experimental or control groups (χ2 (2) =0.33, p=.846). The pseudo-experimental group showed a larger decrease in NA compared to the control group (χ2 (1) =6.29, p=.012). Conclusion PA-focused feedback did not significantly impact daily life PA during or shortly after the intervention. As the previously reported reduction in depressive symptoms associated with the feedback unveiled itself only after weeks, it is conceivable that the effects on daily life PA also evolve

  18. [Application of synergetics to the theory of ontogenesis (on the parametric control of development)].

    PubMed

    Belousov, L V; Chernavskiĭ, D S; Solianik, G I

    1985-01-01

    Applications of synergetics to ontogenesis are discussed. In terms of synergetics, the choice between the concepts of power and parametric control and the description of parameters and dynamic variables of ontogenesis are among the main tasks of the theory of ontogenesis. Examples are provided for multipotency and variability which suggest the parametric control of development. A suggestion is put forward concerning the parameterizing role of directive inductors. Possible ways of overcoming the ambiguity inherent in the parametric control are considered. A general scheme of the ontogenesis control is proposed within the framework of which different types of parameters and dynamic variables are characterized. The concept of chaos is discussed with reference to ontogenesis.

  19. Sense of control under uncertainty depends on people's childhood environment: a life history theory approach.

    PubMed

    Mittal, Chiraag; Griskevicius, Vladas

    2014-10-01

    Past research found that environmental uncertainty leads people to behave differently depending on their childhood environment. For example, economic uncertainty leads people from poor childhoods to become more impulsive while leading people from wealthy childhoods to become less impulsive. Drawing on life history theory, we examine the psychological mechanism driving such diverging responses to uncertainty. Five experiments show that uncertainty alters people's sense of control over the environment. Exposure to uncertainty led people from poorer childhoods to have a significantly lower sense of control than those from wealthier childhoods. In addition, perceptions of control statistically mediated the effect of uncertainty on impulsive behavior. These studies contribute by demonstrating that sense of control is a psychological driver of behaviors associated with fast and slow life history strategies. We discuss the implications of this for theory and future research, including that environmental uncertainty might lead people who grew up poor to quit challenging tasks sooner than people who grew up wealthy.

  20. Shaping femtosecond coherent anti-Stokes Raman spectra using optimal control theory.

    PubMed

    Pezeshki, Soroosh; Schreiber, Michael; Kleinekathöfer, Ulrich

    2008-04-21

    Optimal control theory is used to tailor laser pulses which enhance a femtosecond time-resolved coherent anti-Stokes Raman scattering (fs-CARS) spectrum in a certain frequency range. For this aim the optimal control theory has to be applied to a target state distributed in time. Explicit control mechanisms are given for shaping either the Stokes or the probe pulse in the four-wave mixing process. A simple molecule for which highly accurate potential energy surfaces are available, namely molecular iodine, is used to test the procedure. This approach of controlling vibrational motion and delivering higher intensities to certain frequency ranges might also be important for the improvement of CARS microscopy.

  1. Control theory based airfoil design for potential flow and a finite volume discretization

    NASA Technical Reports Server (NTRS)

    Reuther, J.; Jameson, A.

    1994-01-01

    This paper describes the implementation of optimization techniques based on control theory for airfoil design. In previous studies it was shown that control theory could be used to devise an effective optimization procedure for two-dimensional profiles in which the shape is determined by a conformal transformation from a unit circle, and the control is the mapping function. The goal of our present work is to develop a method which does not depend on conformal mapping, so that it can be extended to treat three-dimensional problems. Therefore, we have developed a method which can address arbitrary geometric shapes through the use of a finite volume method to discretize the potential flow equation. Here the control law serves to provide computationally inexpensive gradient information to a standard numerical optimization method. Results are presented, where both target speed distributions and minimum drag are used as objective functions.

  2. Inseparability of Go and Stop in Inhibitory Control: Go Stimulus Discriminability Affects Stopping Behavior.

    PubMed

    Ma, Ning; Yu, Angela J

    2016-01-01

    Inhibitory control, the ability to stop or modify preplanned actions under changing task conditions, is an important component of cognitive functions. Two lines of models of inhibitory control have previously been proposed for human response in the classical stop-signal task, in which subjects must inhibit a default go response upon presentation of an infrequent stop signal: (1) the race model, which posits two independent go and stop processes that race to determine the behavioral outcome, go or stop; and (2) an optimal decision-making model, which posits that observers decides whether and when to go based on continually (Bayesian) updated information about both the go and stop stimuli. In this work, we probe the relationship between go and stop processing by explicitly manipulating the discrimination difficulty of the go stimulus. While the race model assumes the go and stop processes are independent, and therefore go stimulus discriminability should not affect the stop stimulus processing, we simulate the optimal model to show that it predicts harder go discrimination should result in longer go reaction time (RT), lower stop error rate, as well as faster stop-signal RT. We then present novel behavioral data that validate these model predictions. The results thus favor a fundamentally inseparable account of go and stop processing, in a manner consistent with the optimal model, and contradicting the independence assumption of the race model. More broadly, our findings contribute to the growing evidence that the computations underlying inhibitory control are systematically modulated by cognitive influences in a Bayes-optimal manner, thus opening new avenues for interpreting neural responses underlying inhibitory control.

  3. Inseparability of Go and Stop in Inhibitory Control: Go Stimulus Discriminability Affects Stopping Behavior

    PubMed Central

    Ma, Ning; Yu, Angela J.

    2016-01-01

    Inhibitory control, the ability to stop or modify preplanned actions under changing task conditions, is an important component of cognitive functions. Two lines of models of inhibitory control have previously been proposed for human response in the classical stop-signal task, in which subjects must inhibit a default go response upon presentation of an infrequent stop signal: (1) the race model, which posits two independent go and stop processes that race to determine the behavioral outcome, go or stop; and (2) an optimal decision-making model, which posits that observers decides whether and when to go based on continually (Bayesian) updated information about both the go and stop stimuli. In this work, we probe the relationship between go and stop processing by explicitly manipulating the discrimination difficulty of the go stimulus. While the race model assumes the go and stop processes are independent, and therefore go stimulus discriminability should not affect the stop stimulus processing, we simulate the optimal model to show that it predicts harder go discrimination should result in longer go reaction time (RT), lower stop error rate, as well as faster stop-signal RT. We then present novel behavioral data that validate these model predictions. The results thus favor a fundamentally inseparable account of go and stop processing, in a manner consistent with the optimal model, and contradicting the independence assumption of the race model. More broadly, our findings contribute to the growing evidence that the computations underlying inhibitory control are systematically modulated by cognitive influences in a Bayes-optimal manner, thus opening new avenues for interpreting neural responses underlying inhibitory control. PMID:27047324

  4. Optimal guidance law for cooperative attack of multiple missiles based on optimal control theory

    NASA Astrophysics Data System (ADS)

    Sun, Xiao; Xia, Yuanqing

    2012-08-01

    This article considers the problem of optimal guidance laws for cooperative attack of multiple missiles based on the optimal control theory. New guidance laws are presented such that multiple missiles attack a single target simultaneously. Simulation results show the effectiveness of the proposed algorithms.

  5. Application of Demand-Control Theory to Sign Language Interpreting: Implications for Stress and Interpreter Training.

    ERIC Educational Resources Information Center

    Dean, Robyn K.; Pollard, Robert Q., Jr.

    2001-01-01

    This article uses the framework of demand-control theory to examine the occupation of sign language interpreting. It discusses the environmental, interpersonal, and intrapersonal demands that impinge on the interpreter's decision latitude and notes the prevalence of cumulative trauma disorders, turnover, and burnout in the interpreting profession.…

  6. Searching for the Self: An Identity Control Theory Approach to Triggers of Occupational Exploration

    ERIC Educational Resources Information Center

    Anderson, Katherine L.; Mounts, Nina S.

    2012-01-01

    Identity control theory researchers have found evidence for two processes of identity development (identity defense and identity change) and have theorized a third process (identity exploration). College students (N = 123) self-rated as high or low in occupational identity certainty and importance received self-discrepant feedback to induce…

  7. Training Theory of Mind and Executive Control: A Tool for Improving School Achievement?

    ERIC Educational Resources Information Center

    Kloo, Daniela; Perner, Josef

    2008-01-01

    In the preschool years, there are marked improvements in theory of mind (ToM) and executive functions. And, children's competence in these two core cognitive domains is associated with their academic achievement. Therefore, training ToM and executive control could be a valuable tool for improving children's success in school. This article reviews…

  8. An approximation theory for nonlinear partial differential equations with applications to identification and control

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Kunisch, K.

    1982-01-01

    Approximation results from linear semigroup theory are used to develop a general framework for convergence of approximation schemes in parameter estimation and optimal control problems for nonlinear partial differential equations. These ideas are used to establish theoretical convergence results for parameter identification using modal (eigenfunction) approximation techniques. Results from numerical investigations of these schemes for both hyperbolic and parabolic systems are given.

  9. Theory of Mind Training in Children with Autism: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Begeer, Sander; Gevers, Carolien; Clifford, Pamela; Verhoeve, Manja; Kat, Kirstin; Hoddenbach, Elske; Boer, Frits

    2011-01-01

    Many children with Autism Spectrum Disorders (ASD) participate in social skills or Theory of Mind (ToM) treatments. However, few studies have shown evidence for their effectiveness. The current study used a randomized controlled design to test the effectiveness of a 16-week ToM treatment in 8-13 year old children with ASD and normal IQs (n = 40).…

  10. Children's Eating Attitudes and Behaviour: A Study of the Modelling and Control Theories of Parental Influence

    ERIC Educational Resources Information Center

    Brown, Rachael; Ogden, Jane

    2004-01-01

    The present study compared the modelling and control theories of parental influence on children's eating attitudes and behaviour with a focus on snack foods. Matched questionnaires describing reported snack intake, eating motivations and body dissatisfaction were completed by 112 parent/child pairs. Parents completed additional items relating to…

  11. [The theory and practice of an epidemic control service for the population].

    PubMed

    Livshits, M L; Zenkov, V A; Postovoĭ, P P

    1986-11-01

    The data on the epidemic-control medical care of the population of the Kuznetsk coal fields and on the creation of the specialized system of the epidemiological surveillance of influenza, measles, viral hepatitis, hospital infections are presented. The possibility of using the theory of the self-regulation of the epidemic process in practical work is discussed.

  12. Using interpersonal affect regulation in simulated healthcare consultations: an experimental investigation of self-control resource depletion

    PubMed Central

    Martínez-Íñigo, David; Mercado, Francisco; Totterdell, Peter

    2015-01-01

    Controlled Interpersonal Affect Regulation –the process of deliberately influencing the internal feeling states of others– occurs in a variety of interpersonal relationships and contexts. An incipient corpus of research shows that interpersonal affect regulation can be characterized as a goal-directed behavior that uses self-control processes which, according to the strength model of self-regulation, consumes a limited resource that is also used by other self-control processes. Using interpersonal affect-improving and affect-worsening regulation strategies can increase agent’s resource depletion but there is reason to think that effects will partially rely on target’s feedback in response to the regulation. Using a healthcare paradigm, an experiment was conducted to test the combined effects of interpersonal affect regulation use and patient feedback on healthcare workers’ resource depletion, measured as self-reported experienced and expected emotional exhaustion, and persistence on a self-regulation task. Medical students (N = 78) were randomly assigned to a 2(interpersonal affect regulation: affect-worsening vs. affect-improving) × 2(patients’ feedback: positive vs. negative) factorial between-subjects design and given instructions to play the role of doctors in interactions with two professional actors trained to act as patients. Analysis of covariance showed that affect-worsening was more depleting than affect-improving for all measures, whereas the recovery effects of positive feedback varied depending on strategy type and measure. The findings confirm the characterization of interpersonal affect regulation as potentially depleting, but suggest that the correspondence between the agent’s strategy and the target’s response needs to be taken into consideration. Use of affect-improving and positive feedback showed positive effects on self-rated performance, indicating that interpersonal affect regulation is relevant for organizational as well as

  13. Using interpersonal affect regulation in simulated healthcare consultations: an experimental investigation of self-control resource depletion.

    PubMed

    Martínez-Íñigo, David; Mercado, Francisco; Totterdell, Peter

    2015-01-01

    Controlled Interpersonal Affect Regulation -the process of deliberately influencing the internal feeling states of others- occurs in a variety of interpersonal relationships and contexts. An incipient corpus of research shows that interpersonal affect regulation can be characterized as a goal-directed behavior that uses self-control processes which, according to the strength model of self-regulation, consumes a limited resource that is also used by other self-control processes. Using interpersonal affect-improving and affect-worsening regulation strategies can increase agent's resource depletion but there is reason to think that effects will partially rely on target's feedback in response to the regulation. Using a healthcare paradigm, an experiment was conducted to test the combined effects of interpersonal affect regulation use and patient feedback on healthcare workers' resource depletion, measured as self-reported experienced and expected emotional exhaustion, and persistence on a self-regulation task. Medical students (N = 78) were randomly assigned to a 2(interpersonal affect regulation: affect-worsening vs. affect-improving) × 2(patients' feedback: positive vs. negative) factorial between-subjects design and given instructions to play the role of doctors in interactions with two professional actors trained to act as patients. Analysis of covariance showed that affect-worsening was more depleting than affect-improving for all measures, whereas the recovery effects of positive feedback varied depending on strategy type and measure. The findings confirm the characterization of interpersonal affect regulation as potentially depleting, but suggest that the correspondence between the agent's strategy and the target's response needs to be taken into consideration. Use of affect-improving and positive feedback showed positive effects on self-rated performance, indicating that interpersonal affect regulation is relevant for organizational as well as personal

  14. Lie Group Methods and Control Theory Workshop Held on 28 June-1 July 2004 (CD-ROM)

    DTIC Science & Technology

    CONTROL THEORY , *WORKSHOPS, *LIE GROUPS, ROBOTICS, NUMERICAL INTEGRATION, DIFFERENTIAL EQUATIONS, INTEGRATORS, NONLINEAR ANALYSIS, COMPACT DISKS, GROUPS(MATHEMATICS), SCOTLAND, MANIFOLDS(MATHEMATICS).

  15. Credibility theory based dynamic control bound optimization for reservoir flood limited water level

    NASA Astrophysics Data System (ADS)

    Jiang, Zhiqiang; Sun, Ping; Ji, Changming; Zhou, Jianzhong

    2015-10-01

    The dynamic control operation of reservoir flood limited water level (FLWL) can solve the contradictions between reservoir flood control and beneficial operation well, and it is an important measure to make sure the security of flood control and realize the flood utilization. The dynamic control bound of FLWL is a fundamental key element for implementing reservoir dynamic control operation. In order to optimize the dynamic control bound of FLWL by considering flood forecasting error, this paper took the forecasting error as a fuzzy variable, and described it with the emerging credibility theory in recent years. By combining the flood forecasting error quantitative model, a credibility-based fuzzy chance constrained model used to optimize the dynamic control bound was proposed in this paper, and fuzzy simulation technology was used to solve the model. The FENGTAN reservoir in China was selected as a case study, and the results show that, compared with the original operation water level, the initial operation water level (IOWL) of FENGTAN reservoir can be raised 4 m, 2 m and 5.5 m respectively in the three division stages of flood season, and without increasing flood control risk. In addition, the rationality and feasibility of the proposed forecasting error quantitative model and credibility-based dynamic control bound optimization model are verified by the calculation results of extreme risk theory.

  16. Quantum optimal control theory and dynamic coupling in the spin-boson model

    SciTech Connect

    Jirari, H.; Poetz, W.

    2006-08-15

    A Markovian master equation describing the evolution of open quantum systems in the presence of a time-dependent external field is derived within the Bloch-Redfield formalism. It leads to a system-bath interaction which depends on the control field. Optimal control theory is used to select control fields which allow accelerated or decelerated system relaxation, or suppression of relaxation (dissipation) altogether, depending on the dynamics we impose on the quantum system. The control-dissipation correlation and the nonperturbative treatment of the control field are essential for reaching this goal. The optimal control problem is formulated within Pontryagin's minimum principle and the resulting optimal differential system is solved numerically. As an application, we study the dynamics of a spin-boson model in the strong coupling regime under the influence of an external control field. We show how trapping the system in unstable quantum states and transfer of population can be achieved by optimized control of the dissipative quantum system. We also used optimal control theory to find the driving field that generates the quantum Z gate. In several cases studied, we find that the selected optimal field which reduces the purity loss significantly is a multicomponent low-frequency field including higher harmonics, all of which lie below the phonon cutoff frequency. Finally, in the undriven case we present an analytic result for the Lamb shift at zero temperature.

  17. Moderators of Theory-Based Interventions to Promote Physical Activity in 77 Randomized Controlled Trials.

    PubMed

    Bernard, Paquito; Carayol, Marion; Gourlan, Mathieu; Boiché, Julie; Romain, Ahmed Jérôme; Bortolon, Catherine; Lareyre, Olivier; Ninot, Gregory

    2017-04-01

    A meta-analysis of randomized controlled trials (RCTs) has recently showed that theory-based interventions designed to promote physical activity (PA) significantly increased PA behavior. The objective of the present study was to investigate the moderators of the efficacy of these theory-based interventions. Seventy-seven RCTs evaluating theory-based interventions were systematically identified. Sample, intervention, methodology, and theory implementation characteristics were extracted, coded by three duos of independent investigators, and tested as moderators of interventions effect in a multiple-meta-regression model. Three moderators were negatively associated with the efficacy of theory-based interventions on PA behavior: intervention length (≥14 weeks; β = -.22, p = .004), number of experimental patients (β = -.10, p = .002), and global methodological quality score (β = -.08, p = .04). Our findings suggest that the efficacy of theory-based interventions to promote PA could be overestimated consequently due to methodological weaknesses of RCTs and that interventions shorter than 14 weeks could maximize the increase of PA behavior.

  18. Quinine controls body weight gain without affecting food intake in male C57BL6 mice

    PubMed Central

    2013-01-01

    Background Quinine is a natural molecule commonly used as a flavouring agent in tonic water. Diet supplementation with quinine leads to decreased body weight and food intake in rats. Quinine is an in vitro inhibitor of Trpm5, a cation channel expressed in taste bud cells, the gastrointestinal tract and pancreas. The objective of this work is to determine the effect of diet supplementation with quinine on body weight and body composition in male mice, to investigate its mechanism of action, and whether the effect is mediated through Trpm5. Results Compared with mice consuming AIN, a regular balanced diet, mice consuming AIN diet supplemented with 0.1% quinine gained less weight (2.89 ± 0.30 g vs 5.39 ± 0.50 g) and less fat mass (2.22 ± 0.26 g vs 4.33 ± 0.43 g) after 13 weeks of diet, and had lower blood glucose and plasma triglycerides. There was no difference in food intake between the mice consuming quinine supplemented diet and those consuming control diet. Trpm5 knockout mice gained less fat mass than wild-type mice. There was a trend for a diet-genotype interaction for body weight and body weight gain, with the effect of quinine less pronounced in the Trpm5 KO than in the WT background. Faecal weight, energy and lipid contents were higher in quinine fed mice compared to regular AIN fed mice and in Trpm5 KO mice compared to wild type mice. Conclusion Quinine contributes to weight control in male C57BL6 mice without affecting food intake. A partial contribution of Trpm5 to quinine dependent body weight control is suggested. PMID:23394313

  19. Integrating care for neurodevelopmental disorders by unpacking control: A grounded theory study

    PubMed Central

    Waxegård, Gustaf; Thulesius, Hans

    2016-01-01

    Background To establish integrated healthcare pathways for patients with neurodevelopmental disorders (ND) such as autism spectrum disorder and attention-deficit hyperactivity disorder is challenging. This study sets out to investigate the main concerns for healthcare professionals when integrating ND care pathways and how they resolve these concerns. Methods Using classic grounded theory (Glaser), we analysed efforts to improve and integrate an ND care pathway for children and youth in a Swedish region over a period of 6 years. Data from 42 individual interviews with a range of ND professionals, nine group interviews with healthcare teams, participant observation, a 2-day dialogue conference, focus group meetings, regional media coverage, and reports from other Swedish regional ND projects were analysed. Results The main concern for participants was to deal with overwhelming ND complexity by unpacking control, which is control over strategies to define patients’ status and needs. Unpacking control is key to the professionals’ strivings to expand constructive life space for patients, to squeeze health care to reach available care goals, to promote professional ideologies, and to uphold workplace integrity. Control-seeking behaviour in relation to ND unpacking is ubiquitous and complicates integration of ND care pathways. Conclusions The Unpacking control theory expands central aspects of professions theory and may help to improve ND care development. PMID:27609793

  20. Testing predictions from the male control theory of men's partner violence.

    PubMed

    Bates, Elizabeth A; Graham-Kevan, Nicola; Archer, John

    2014-01-01

    The aim of this study was to test predictions from the male control theory of intimate partner violence (IPV) and Johnson's [Johnson, M. P. (1995). Journal of Marriage and the Family, 57, 282-294] typology. A student sample (N = 1,104) reported on their use of physical aggression and controlling behavior, to partners and to same-sex non-intimates. Contrary to the male control theory, women were found to be more physically aggressive to their partners than men were, and the reverse pattern was found for aggression to same-sex non-intimates. Furthermore, there were no substantial sex differences in controlling behavior, which significantly predicted physical aggression in both sexes. IPV was found to be associated with physical aggression to same-sex non-intimates, thereby demonstrating a link with aggression outside the family. Using Johnson's typology, women were more likely than men to be classed as "intimate terrorists," which was counter to earlier findings. Overall, these results do not support the male control theory of IPV. Instead, they fit the view that IPV does not have a special etiology, and is better studied within the context of other forms of aggression.

  1. [A nurse's experience applying Rotter's locus of control theory in a myocardial infarction patient].

    PubMed

    Shi, Meng-Ling; Ke, Ya-Ting

    2009-04-01

    This case report shares the experience of one nurse in applying Rotter's locus of control theory in her care of a myocardial infarction patient. Period of care ran from November 23 to December 1, 2007. The author collected subjective and objective data through observations and interviews with the patient in the ward. Data was analyzed to identify key healthcare problems. These included the inadequate information of the patient on his condition, which negatively influenced health behavior; inadequate health information available; and the flare-up of disease symptoms. Internal locus of control, as presented in Rotter's locus of control theory, was applied to the above nursing problems in order to deliver individualized nursing care to the patient based on mutual trust. Such enhanced patient disease cognition, facilitated his obtaining health information, helped him adjust to disease symptom episodes, and promoted his adjustment to the disease and adoption of more healthy behavior.

  2. Aerodynamic shape optimization of wing and wing-body configurations using control theory

    NASA Technical Reports Server (NTRS)

    Reuther, James; Jameson, Antony

    1995-01-01

    This paper describes the implementation of optimization techniques based on control theory for wing and wing-body design. In previous studies it was shown that control theory could be used to devise an effective optimization procedure for airfoils and wings in which the shape and the surrounding body-fitted mesh are both generated analytically, and the control is the mapping function. Recently, the method has been implemented for both potential flows and flows governed by the Euler equations using an alternative formulation which employs numerically generated grids, so that it can more easily be extended to treat general configurations. Here results are presented both for the optimization of a swept wing using an analytic mapping, and for the optimization of wing and wing-body configurations using a general mesh.

  3. Quantitative Feedback Theory (QFT) applied to the design of a rotorcraft flight control system

    NASA Technical Reports Server (NTRS)

    Hess, R. A.; Gorder, P. J.

    1992-01-01

    Quantitative Feedback Theory describes a frequency-domain technique for the design of multi-input, multi-output control systems which meet time or frequency domain performance criteria when specified uncertainty exists in the linear description of the vehicle dynamics. Quantitative Feedback Theory is applied to the design of the longitudinal flight control system for a linear uncertain model of the AH-64 rotorcraft. In this model, the uncertainty is assigned, and is assumed to be attributable to actual uncertainty in the dynamic model and to the changes in the vehicle aerodynamic characteristics which occur near hover. The model includes an approximation to the rotor and actuator dynamics. The design example indicates the manner in which handling qualities criteria may be incorporated into the design of realistic rotorcraft control systems in which significant uncertainty exists in the vehicle model.

  4. Realization theory and quadratic optimal controllers for systems defined over Banach and Frechet algebras

    NASA Technical Reports Server (NTRS)

    Byrnes, C. I.

    1980-01-01

    It is noted that recent work by Kamen (1979) on the stability of half-plane digital filters shows that the problem of the existence of a feedback law also arises for other Banach algebras in applications. This situation calls for a realization theory and stabilizability criteria for systems defined over Banach for Frechet algebra A. Such a theory is developed here, with special emphasis placed on the construction of finitely generated realizations, the existence of coprime factorizations for T(s) defined over A, and the solvability of the quadratic optimal control problem and the associated algebraic Riccati equation over A.

  5. A theory of local and global processes which affect solar wind electrons. 1: The origin of typical 1 AU velocity distribution functions: Steady state theory

    NASA Technical Reports Server (NTRS)

    Scudder, J. D.

    1978-01-01

    A detailed first principle kinetic theory for electrons which is neither a classical fluid treatment nor an exospheric calculation is presented. This theory illustrates the global and local properties of the solar wind expansion that shape the observed features of the electron distribution function, such as its bifurcation, its skewness and the differential temperatures of the thermal and suprathermal subpopulations. Coulomb collisions are substantial mediators of the interplanetary electron velocity distribution function and they place a zone for a bifurcation of the electron distribution function deep in the corona. The local cause and effect precept which permeates the physics of denser media is modified for electrons in the solar wind. The local form of transport laws and equations of state which apply to collision dominated plasmas are replaced with global relations that explicitly depend on the relative position of the observer to the boundaries of the system.

  6. Numerical Algorithms and Mathematical Software for Linear Control and Estimation Theory.

    DTIC Science & Technology

    1985-05-30

    RD -R157 525 NUMERICAL ALGORITHMS AND MATHEMATICAL SOFTWJARE FOR i/i LINEAR CONTROL AND EST..U) MASSACHUSETTS INST OF TECH CAMBRIDGE STATISTICS...PERIOD COVERED"~~ "ia--Dec. 14, 1981-- LD Numerical Algorithms and Mathematical Dec. 13, 1984*Software for Linear Control and 1.0 Estimation Theory...THIS PAGE (Wten Date Entered) .. :..0 70 FINAL REPORT--ARO Grant DAAG29-82-K-0028,"Numerical Algorithms and Mathematical Software for Linear Control and

  7. APPLICATION OF OPTIMAL CONTROL THEORY TO CARDIO-CIRCULATORY ASSIST DEVICES.

    DTIC Science & Technology

    The objective of the investigation is the application of, and where necessary, extension of optimal control theory to the synthesis of controllers for such cardio-circulatory assist devices. In particular, the concept of set of attainability is extended to include linear, periodic, bounded control systems and the maximum principle applied to obtain necessary and sufficient conditions for various problems. In addition to several numerical examples, the results of a large-scale hybrid simulation for a cardiovascular model and particular assist device are presented.

  8. REVIEW: Internal models in sensorimotor integration: perspectives from adaptive control theory

    NASA Astrophysics Data System (ADS)

    Tin, Chung; Poon, Chi-Sang

    2005-09-01

    Internal models and adaptive controls are empirical and mathematical paradigms that have evolved separately to describe learning control processes in brain systems and engineering systems, respectively. This paper presents a comprehensive appraisal of the correlation between these paradigms with a view to forging a unified theoretical framework that may benefit both disciplines. It is suggested that the classic equilibrium-point theory of impedance control of arm movement is analogous to continuous gain-scheduling or high-gain adaptive control within or across movement trials, respectively, and that the recently proposed inverse internal model is akin to adaptive sliding control originally for robotic manipulator applications. Modular internal models' architecture for multiple motor tasks is a form of multi-model adaptive control. Stochastic methods, such as generalized predictive control, reinforcement learning, Bayesian learning and Hebbian feedback covariance learning, are reviewed and their possible relevance to motor control is discussed. Possible applicability of a Luenberger observer and an extended Kalman filter to state estimation problems—such as sensorimotor prediction or the resolution of vestibular sensory ambiguity—is also discussed. The important role played by vestibular system identification in postural control suggests an indirect adaptive control scheme whereby system states or parameters are explicitly estimated prior to the implementation of control. This interdisciplinary framework should facilitate the experimental elucidation of the mechanisms of internal models in sensorimotor systems and the reverse engineering of such neural mechanisms into novel brain-inspired adaptive control paradigms in future.

  9. Bridges from affect to language. Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

    NASA Astrophysics Data System (ADS)

    Schmidtke, David S.; Aryani, Arash

    2015-06-01

    The comprehensive Quartet Theory of Human Emotions proposed by Koelsch et al. [4] offers an exceptional synopsis regarding major developments in affective neuroscience, encompassing classical data based on animal studies as well as emotions generally classified as uniquely human. In doing so, it becomes apparent that while general anatomical grounds appear well covered mainly based on animal studies, neuroanatomical underpinnings of interactions between emotion and language may not be readily understood.

  10. Tracking control of a leg rehabilitation machine driven by pneumatic artificial muscles using composite fuzzy theory.

    PubMed

    Chang, Ming-Kun

    2014-01-01

    It is difficult to achieve excellent tracking performance for a two-joint leg rehabilitation machine driven by pneumatic artificial muscles (PAMs) because the system has a coupling effect, highly nonlinear and time-varying behavior associated with gas compression, and the nonlinear elasticity of bladder containers. This paper therefore proposes a T-S fuzzy theory with supervisory control in order to overcome the above problems. The T-S fuzzy theory decomposes the model of a nonlinear system into a set of linear subsystems. In this manner, the controller in the T-S fuzzy model is able to use simple linear control techniques to provide a systematic framework for the design of a state feedback controller. Then the LMI Toolbox of MATLAB can be employed to solve linear matrix inequalities (LMIs) in order to determine controller gains based on the Lyapunov direct method. Moreover, the supervisory control can overcome the coupling effect for a leg rehabilitation machine. Experimental results show that the proposed controller can achieve excellent tracking performance, and guarantee robustness to system parameter uncertainties.

  11. Tracking Control of a Leg Rehabilitation Machine Driven by Pneumatic Artificial Muscles Using Composite Fuzzy Theory

    PubMed Central

    2014-01-01

    It is difficult to achieve excellent tracking performance for a two-joint leg rehabilitation machine driven by pneumatic artificial muscles (PAMs) because the system has a coupling effect, highly nonlinear and time-varying behavior associated with gas compression, and the nonlinear elasticity of bladder containers. This paper therefore proposes a T-S fuzzy theory with supervisory control in order to overcome the above problems. The T-S fuzzy theory decomposes the model of a nonlinear system into a set of linear subsystems. In this manner, the controller in the T-S fuzzy model is able to use simple linear control techniques to provide a systematic framework for the design of a state feedback controller. Then the LMI Toolbox of MATLAB can be employed to solve linear matrix inequalities (LMIs) in order to determine controller gains based on the Lyapunov direct method. Moreover, the supervisory control can overcome the coupling effect for a leg rehabilitation machine. Experimental results show that the proposed controller can achieve excellent tracking performance, and guarantee robustness to system parameter uncertainties. PMID:24778583

  12. Muscular contraction mode differently affects autonomic control during heart rate matched exercise.

    PubMed

    Weippert, Matthias; Behrens, Martin; Gonschorek, Ray; Bruhn, Sven; Behrens, Kristin

    2015-01-01

    The precise contributions of afferent feedback to cardiovascular and respiratory responses to exercise are still unclear. The aim of this crossover study was to assess whether and how autonomic cardiovascular and respiratory control differed in response to dynamic (DYN) and isometric contractions (ISO) at a similar, low heart rate (HR) level. Therefore, 22 healthy males (26.7 ± 3.6 yrs) performed two kinds of voluntary exercises at similar HR: ISO and DYN of the right quadriceps femoris muscle. Although HR was eqivalent (82 ± 8 bpm for DYN and ISO, respectively), rating of exertion, blood pressures, and rate pressure product were higher, whereas breathing frequency, minute ventilation, oxygen uptake and carbon dioxide output were significantly lower during ISO. Tidal volume, end-tidal partial pressures of O2 and CO2, respiratory exchange ratio and capillary blood lactate concentration were comparable between both contraction modes. Heart rate variability (HRV) indicators, SDNN, HF-Power and LF-Power, representing both vagal and sympathetic influences, were significantly higher during ISO. Sample entropy, a non-linear measure of HRV was also significantly affected by contraction mode. It can be concluded that, despite the same net effect on HR, the quality of cardiovascular control during low intensity exercise is significantly different between DYN and ISO. HRV analysis indicated a sympatho-vagal coactivation during ISO. Whether mechanoreceptor feedback alone, a change in central command, or the interaction of both mechanisms is the main contributor of the distinct autonomic responses to the different exercise modes remains to be elucidated.

  13. A Randomized Controlled Trial of Cognitive-Behavioral Therapy, Light Therapy, and Their Combination for Seasonal Affective Disorder

    ERIC Educational Resources Information Center

    Rohan, Kelly J.; Roecklein, Kathryn A.; Tierney Lindsey, Kathryn; Johnson, Leigh G.; Lippy, Robert D.; Lacy, Timothy J.; Barton, Franca B.

    2007-01-01

    This first controlled psychotherapy trial for seasonal affective disorder (SAD) compared SAD-tailored cognitive-behavioral therapy (CBT), light therapy (LT), and their combination to a concurrent wait-list control. Adults (N = 61) with major depression, recurrent with seasonal pattern, were randomized to one of four 6-week conditions: CBT (1.5-hr…

  14. Need for Affect, Need for Cognition, and the Intention-Fruit Consumption Relationship: An Action-Control Perspective

    ERIC Educational Resources Information Center

    de Bruijn, Gert-Jan; Keer, Mario; van den Putte, Bas; Neijens, Peter

    2012-01-01

    Objective: Predictors of action-control profiles are useful targets for health behaviour change interventions, but action-control research has not focused on fruit consumption and has not yet included need for affect and need for cognition, despite the demonstrated usefulness of these variables in a broad range of research. The role of these…

  15. Theodor Waitz's theory of feelings and the rise of affective sciences in the mid-19th century.

    PubMed

    Romand, David

    2015-11-01

    The German psychologist Theodor Waitz (1821-1864) was an important theorist of affectivity in the mid-19th century. This article aims to revisit Waitz's contribution to affective psychology at a crucial moment of its history. First, I elaborate the context in which Waitz's ideas were carried out by showing how affective sciences emerged as an autonomous field of investigation between about 1770 and 1910. Second, I discuss the principles of Waitz's model of affectivity and their contextual significance. Third, I deal with the first major category of affective states identified by Waitz, namely, "formal feelings," which are supposed to be involved in the appraisal of the relational properties between representations. Fourth, I investigate "qualitative feelings," the second major category of affective states identified by Waitz, which refer to affective processes that relate to specific representational contents, namely, intellectual, aesthetic, and moral feelings. In conclusion, I emphasize the genealogical link between Waitz's pioneering research on musical feelings and current research on emotion and expectation in music.

  16. Application of demand-control theory to sign language interpreting: implications for stress and interpreter training.

    PubMed

    Dean, R K; Pollard, R Q

    2001-01-01

    The translation work of sign language interpreters involves much more than language. The characteristics and goings-on in the physical environment, the dynamics and interactions between the people who are present, and even the "inner noise" of the interpreter contribute to the accuracy, or lack thereof, of the resulting translation. The competent interpreter must understand and respond appropriately to the language and nonlanguage aspects of each interpreting assignment. We use the framework of demand-control theory (Karasek, 1979) to examine the complex occupation of sign language interpreting. Demand-control theory is a job analysis method useful in studies of occupational stress and reduction of stress-related illness, injury, and burnout. We describe sources of demand in the interpreting profession, including demands that arise from factors other than those associated with languages (linguistic demands). These include environmental, interpersonal, and intrapersonal demands. Karasek's concept of control, or decision latitude, is also explored in relation to the interpreting profession. We discuss the prevalence of cumulative trauma disorders (CTD), turnover, and burnout in the interpreting profession in light of demand-control theory and data from interpreter surveys, including a new survey study described herein. We conclude that nonlinguistic demand factors in particular and perceived restrictions in decision latitude likely contribute to stress, CTD, burnout, and the resulting shortage of sign language interpreters. We make suggestions for improvements in interpreter education and professional development, including the institution of an advanced, supervised professional training period, modeled after internships common in other high demand professional occupations.

  17. Dot Display Affects Approximate Number System Acuity and Relationships with Mathematical Achievement and Inhibitory Control

    PubMed Central

    Norris, Jade Eloise; Castronovo, Julie

    2016-01-01

    Much research has investigated the relationship between the Approximate Number System (ANS) and mathematical achievement, with continued debate surrounding the existence of such a link. The use of different stimulus displays may account for discrepancies in the findings. Indeed, closer scrutiny of the literature suggests that studies supporting a link between ANS acuity and mathematical achievement in adults have mostly measured the ANS using spatially intermixed displays (e.g. of blue and yellow dots), whereas those failing to replicate a link have primarily used spatially separated dot displays. The current study directly compared ANS acuity when using intermixed or separate dots, investigating how such methodological variation mediated the relationship between ANS acuity and mathematical achievement. ANS acuity was poorer and less reliable when measured with intermixed displays, with performance during both conditions related to inhibitory control. Crucially, mathematical achievement was significantly related to ANS accuracy difference (accuracy on congruent trials minus accuracy on incongruent trials) when measured with intermixed displays, but not with separate displays. The findings indicate that methodological variation affects ANS acuity outcomes, as well as the apparent relationship between the ANS and mathematical achievement. Moreover, the current study highlights the problem of low reliabilities of ANS measures. Further research is required to construct ANS measures with improved reliability, and to understand which processes may be responsible for the increased likelihood of finding a correlation between the ANS and mathematical achievement when using intermixed displays. PMID:27195749

  18. The threat of a support surface translation affects anticipatory postural control.

    PubMed

    Phanthanourak, Angel L; Cleworth, Taylor W; Adkin, Allan L; Carpenter, Mark G; Tokuno, Craig D

    2016-10-01

    This study examined how postural threat in the form of a potential perturbation affects an individual's ability to perform a heel raise. Seventeen adults completed three conditions: i) low threat, where participants performed a heel raise in response to a "go" tone, ii) high threat, where participants either heard the same "go" tone, for which they performed a heel raise, or experienced a support surface translation in the medio-lateral direction that disturbed their balance, and iii) choice reaction time task, where participants either completed a heel raise in response to the same "go" tone or a toe raise in response to a lower pitched tone. For all heel raise trials, anticipatory postural adjustments (APAs) were quantified from center of pressure (COP) recordings and electromyographic (EMG) activity from the tibialis anterior (TA) and soleus (SOL). Results indicated that participants exhibited larger APAs, as reflected by the greater backward COP displacement (p=0.038) and velocity (p=0.022) as well as a larger TA EMG amplitude (p=0.045), during the high threat condition. During the execution phase of the heel raise, an earlier (p=0.014) and larger (p=0.041) SOL EMG activation were observed during the high threat condition. These results contrast with previous findings of reduced APAs when the postural threat was evoked through changes in surface height. Therefore, the characteristics of the postural threat must be considered to isolate the effects of threat on anticipatory movement control.

  19. Characterization of a regulatory unit that controls melanization and affects longevity of mosquitoes

    PubMed Central

    An, Chunju; Budd, Aidan; Kanost, Michael R.; Michel, Kristin

    2010-01-01

    Melanization is an innate immune response in arthropods that encapsulates and kills invading pathogens. One of its rate-limiting steps is the activation of prophenoloxidase (PPO), which is controlled by an extracellular proteinase cascade and serpin inhibitors. The molecular composition of this system is largely unknown in mosquitoes with the exception of serpin-2 (SRPN2), which was previously identified as a key negative regulator of melanization. Using reverse genetic and biochemical techniques we identified the Anopheles gambiae clip-serine proteinase CLIPB9 as a PPO-activating proteinase, which is inhibited by SRPN2. Double-knockdown of SRPN2 and CLIPB9 reversed the pleiotrophic phenotype induced by SRPN2 silencing. This study identifies the first inhibitory serpin-serine proteinase pair in mosquitoes, and defines a regulatory unit of melanization. Additionally, the interaction of CLIPB9 and SRPN2 affects the life span of adult female mosquitoes, and therefore constitutes a well-defined potential molecular target for novel Late-Life Acting insecticides. PMID:20953892

  20. Interleukin-12 (IL-12), but not IL-23, deficiency ameliorates viral encephalitis without affecting viral control.

    PubMed

    Kapil, Parul; Atkinson, Roscoe; Ramakrishna, Chandran; Cua, Daniel J; Bergmann, Cornelia C; Stohlman, Stephen A

    2009-06-01

    The relative contributions of interleukin-12 (IL-12) and IL-23 to viral pathogenesis have not been extensively studied. IL-12p40 mRNA rapidly increases after neurotropic coronavirus infection. Infection of mice defective in both IL-12 and IL-23 (p40(-/-)), in IL-12 alone (p35(-/-)), and in IL-23 alone (p19(-/-)) revealed that the symptoms of coronavirus-induced encephalitis are regulated by IL-12. IL-17-producing cells never exceeded background levels, supporting a redundant role of IL-23 in pathogenesis. Viral control, tropism, and demyelination were all similar in p35(-/-), p19(-/-), and wild-type mice. Reduced morbidity in infected IL-12 deficient mice was also not associated with altered recruitment or composition of inflammatory cells. However, gamma interferon (IFN-gamma) levels and virus-specific IFN-gamma-secreting CD4 and CD8 T cells were all reduced in the central nervous systems (CNS) of infected p35(-/-) mice. Transcription of the proinflammatory cytokines IL-1beta and IL-6, but not tumor necrosis factor, were initially reduced in infected p35(-/-) mice but increased to wild-type levels during peak inflammation. Furthermore, although transforming growth factor beta mRNA was not affected, IL-10 was increased in the CNS in the absence of IL-12. These data suggest that IL-12 does not contribute to antiviral function within the CNS but enhances morbidity associated with viral encephalitis by increasing the ratio of IFN-gamma to protective IL-10.

  1. Controlled cortical impact before or after fear conditioning does not affect fear extinction in mice.

    PubMed

    Sierra-Mercado, Demetrio; McAllister, Lauren M; Lee, Christopher C H; Milad, Mohammed R; Eskandar, Emad N; Whalen, Michael J

    2015-05-05

    Post-traumatic stress disorder (PTSD) is characterized in part by impaired extinction of conditioned fear. Traumatic brain injury (TBI) is thought to be a risk factor for development of PTSD. We tested the hypothesis that controlled cortical impact (CCI) would impair extinction of fear learned by Pavlovian conditioning, in mice. To mimic the scenarios in which TBI occurs prior to or after exposure to an aversive event, severe CCI was delivered to the left parietal cortex at one of two time points: (1) Prior to fear conditioning, or (2) after conditioning. Delay auditory conditioning was achieved by pairing a tone with a foot shock in "context A". Extinction training involved the presentation of tones in a different context (context B) in the absence of foot shock. Test for extinction memory was achieved by presentation of additional tones alone in context B over the following two days. In pre- or post-injury paradigms, CCI did not influence fear learning and extinction. Furthermore, CCI did not affect locomotor activity or elevated plus maze testing. Our results demonstrate that, within the time frame studied, CCI does not impair the acquisition and expression of conditioned fear or extinction memory.

  2. Food source affects the expression of vitellogenin and fecundity of a biological control agent, Neoseiulus cucumeris.

    PubMed

    Zhao, Yunlong; Li, Dunsong; Zhang, Min; Chen, Wei; Zhang, Guren

    2014-07-01

    Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) is one of the most widely used and important biological control agents for thrips and other small pests worldwide. In the present study, we cloned two cDNAs of vitellogenins (Vgs, NcVg1 and NcVg2) and analyzed the effect of food source on the expression of both Vgs and fecundity in female adults. NcVgs showed higher sequence similarity to Vgs from Parasitiformes. Both neighbor-joining and maximum likelihood methods for phylogenetic analysis of NcVgs yielded similar topologies and showed that the Parasitiformes except Haemaphysalis longicornis segregated into a single clade that was separated into two subclades including one of both Vgs from N. cucumeris. Both transcripts, NcVg1 and NcVg2 revealed similar trends during developmental periods and reached the maximum level at the pre-oviposition period. When fed with different food sources, both NcVg1 and NcVg2 of female adults demonstrated a significant difference (P < 0.05) during the pre-oviposition period. Meanwhile, a positive correlation between the expression of Vgs and fecundity was observed. Therefore, the nutrients provided by the food sources affected fecundity resulting in differential expression of Vgs. Vitellogenin expression can be used as a molecular marker of fecundity of N. cucumeris.

  3. Steering of Frequency Standards by the Use of Linear Quadratic Gaussian Control Theory

    NASA Technical Reports Server (NTRS)

    Koppang, Paul; Leland, Robert

    1996-01-01

    Linear quadratic Gaussian control is a technique that uses Kalman filtering to estimate a state vector used for input into a control calculation. A control correction is calculated by minimizing a quadratic cost function that is dependent on both the state vector and the control amount. Different penalties, chosen by the designer, are assessed by the controller as the state vector and control amount vary from given optimal values. With this feature controllers can be designed to force the phase and frequency differences between two standards to zero either more or less aggressively depending on the application. Data will be used to show how using different parameters in the cost function analysis affects the steering and the stability of the frequency standards.

  4. Digital signal processing and control and estimation theory -- Points of tangency, area of intersection, and parallel directions

    NASA Technical Reports Server (NTRS)

    Willsky, A. S.

    1976-01-01

    A number of current research directions in the fields of digital signal processing and modern control and estimation theory were studied. Topics such as stability theory, linear prediction and parameter identification, system analysis and implementation, two-dimensional filtering, decentralized control and estimation, image processing, and nonlinear system theory were examined in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the two disciplines. An extensive bibliography is included.

  5. Action Control, Motivated Strategies, and Integrative Motivation as Predictors of Language Learning Affect and the Intention to Continue Learning French

    ERIC Educational Resources Information Center

    MacIntyre, Peter D.; Blackie, Rebecca A.

    2012-01-01

    The present study examines the relative ability of variables from three motivational frameworks to predict four non-linguistic outcomes of language learning. The study examines Action Control Theory with its measures of (1) hesitation, (2) volatility and (3) rumination. The study also examined Pintrich's expectancy-value model that uses measures…

  6. The Control-Value Theory of Achievement Emotions: Assumptions, Corollaries, and Implications for Educational Research and Practice

    ERIC Educational Resources Information Center

    Pekrun, Reinhard

    2006-01-01

    This article describes the control-value theory of achievement emotions and its implications for educational research and practice. The theory provides an integrative framework for analyzing the antecedents and effects of emotions experienced in achievement and academic settings. It is based on the premise that appraisals of control and values are…

  7. Opportunities, Rational Choice, and Self-Control: On the Interaction of Person and Situation in a General Theory of Crime

    ERIC Educational Resources Information Center

    Seipel, Christian; Eifler, Stefanie

    2010-01-01

    In this article, deviant action is analyzed on the basis of ideas derived from Gottfredson and Hirschi's self-control theory. Presumedly, self-control in interaction with opportunities can explain deviant action. This assumption is elaborated using the concept of high- and low-cost situations from rational choice theory. From this point of view,…

  8. Individual Differences in Executive Functioning and Theory of Mind: An Investigation of Inhibitory Control and Planning Ability

    ERIC Educational Resources Information Center

    Carlson, Stephanie M.; Moses, Louis J.; Claxton, Laura J.

    2004-01-01

    This research examined the relative contributions of two aspects of executive function--inhibitory control and planning ability--to theory of mind in 49 3- and 4-year-olds. Children were given two standard theory of mind measures (Appearance-Reality and False Belief), three inhibitory control tasks (Bear/Dragon, Whisper, and Gift Delay), three…

  9. Ross, Macdonald, and a Theory for the Dynamics and Control of Mosquito-Transmitted Pathogens

    PubMed Central

    Smith, David L.; Battle, Katherine E.; Hay, Simon I.; Barker, Christopher M.; Scott, Thomas W.; McKenzie, F. Ellis

    2012-01-01

    Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various “Ross-Macdonald” mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955–1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention. PMID:22496640

  10. Ross, macdonald, and a theory for the dynamics and control of mosquito-transmitted pathogens.

    PubMed

    Smith, David L; Battle, Katherine E; Hay, Simon I; Barker, Christopher M; Scott, Thomas W; McKenzie, F Ellis

    2012-01-01

    Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various "Ross-Macdonald" mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955-1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention.

  11. An appraisal of linear systems theory with applications to attitude control. Report to ESTEC

    NASA Astrophysics Data System (ADS)

    Crouch, P. E.; Pritchard, A. J.; Carmichael, N.; Lobry, C.

    1980-05-01

    Nonlinear system theory was reviewed with the emphasis on its relevance to significant attitude control problems in stability and in controllability with a limited number of torques. Suitably chosen attitude control systems were studied in order to produce detailed conclusions of import to realistic design and synthesis requirements. In the general framework of systems analysis nonlinear differential equations were handled with the notion of a differentiable manifold along with all its geometric and analytic ramifications. The fundamental concepts were outlined in a manner accessible to most engineers. Global asymptotically stabilizing controls for two types of actuator system were defined, and controllability criteria for both two torques and one torque by gas jets were set.

  12. Using Wenger's Social Theory of Learning to Examine University Teachers' Understanding of How Instructional Technology Affects Their Experience in Practice

    ERIC Educational Resources Information Center

    Adams, Laura L.

    2010-01-01

    The purpose of this study was to take an exploratory look at how university teachers come to understand their experience in educational practice and their professional role as teachers who integrate instructional technology into their coursework using the framework provided by Wenger's Social Theory of Learning. University faculty who teach in a…

  13. Cohorts and Relatedness: Self-Determination Theory as an Explanation of How Learning Communities Affect Educational Outcomes

    ERIC Educational Resources Information Center

    Beachboard, Martine Robinson; Beachboard, John C.; Li, Wenling; Adkison, Stephen R.

    2011-01-01

    This study examines whether feelings of relatedness constitute a substantial means by which learning communities (cohorts) improve learning outcomes in higher education. It applies Ryan and Deci's Self-Determination Theory to an analysis of the National Survey of Student Engagement. The SDT hypothesizes that environments that support perceptions…

  14. Predictive Poincaré control: A control theory for chaotic systems

    NASA Astrophysics Data System (ADS)

    Schweizer, Jörg; Kennedy, Michael Peter

    1995-11-01

    One of the most interesting features of chaotic systems is the large number of unstable orbits embedded in a chaotic attractor. In this work, we propose a global chaos-control technique called predictive Poincaré control (PPC) that permits stabilization of a predefined solution, using only small control pulses. We prove this result for a large class of n-dimensional chaotic systems. The predefined solution can be a periodic or nonperiodic oscillation, expressed by a periodic or nonperiodic symbolic sequence [S. Hayes, C. Grebogi, and E. Ott, Phys. Rev. Lett. 70, 3031 (1993)]. We apply the general PPC scheme to the well known Lorenz model and study its robustness with respect to parasitic effects.

  15. Stability and Control Harmony in Approach and Landing. [analysis of factors affecting flight characteristics at low airspeeds

    NASA Technical Reports Server (NTRS)

    Anderson, S. B.

    1975-01-01

    A review of the factors which affect stability and control harmony in approach and landing is made to obtain a clearer understanding of the proper relationship, the trade-offs involved, and to show how limits in stability and control harmony are established for advanced aircraft. Factors which influence stability and control harmony include the longitudinal short period response of the aircraft and the level of several pitch control characteristics including control power, control sensitivity, and control feel. At low stability levels for advanced aircraft, less conventional control techniques such as DLC are needed to improve harmony and some form of stability augmentation must be provided to improve precession of flight path control and reduce pilot work load.

  16. What motivates the sexual double standard? More support for male versus female control theory.

    PubMed

    Rudman, Laurie A; Fetterolf, Janell C; Sanchez, Diana T

    2013-02-01

    The present research uniquely compared male control theory (MCT) versus female control theory (FCT) to illuminate motives for the sexual double standard (SDS), whereby men gain status from engaging in casual sex or having many sexual partners, but women are stigmatized for it. Consistent with MCT, men were more likely than women to endorse the SDS and to give sexual advice in ways that reinforce it-gender differences that were mediated by hostile sexism (HS) and endorsing the SDS, respectively. The data did not support FCT's argument that women are motivated by sexual economics to restrict female sexuality (Baumeister & Twenge, 2002). Both genders discouraged women from having casual sex to protect women from social stigma and rape myths that justify violence against sexual women. In concert, the findings support MCT more than FCT and suggest that sexism, stigma, and rape myths are primary obstacles to sexual equality.

  17. Management of redundancy in flight control systems using optimal decision theory

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The problem of using redundancy that exists between dissimilar systems in aircraft flight control is addressed. That is, using the redundancy that exists between a rate gyro and an accelerometer--devices that have dissimilar outputs which are related only through the dynamics of the aircraft motion. Management of this type of redundancy requires advanced logic so that the system can monitor failure status and can reconfigure itself in the event of one or more failures. An optimal decision theory was tutorially developed for the management of sensor redundancy and the theory is applied to two aircraft examples. The first example is the space shuttle and the second is a highly maneuvering high performance aircraft--the F8-C. The examples illustrate the redundancy management design process and the performance of the algorithms presented in failure detection and control law reconfiguration.

  18. Rotorcraft control system design for uncertain vehicle dynamics using quantitative feedback theory

    NASA Technical Reports Server (NTRS)

    Hess, R. A.

    1994-01-01

    Quantitative Feedback Theory describes a frequency-domain technique for the design of multi-input, multi-output control systems which must meet time or frequency domain performance criteria when specified uncertainty exists in the linear description of the vehicle dynamics. This theory is applied to the design of the longitudinal flight control system for a linear model of the BO-105C rotorcraft. Uncertainty in the vehicle model is due to the variation in the vehicle dynamics over a range of airspeeds from 0-100 kts. For purposes of exposition, the vehicle description contains no rotor or actuator dynamics. The design example indicates the manner in which significant uncertainty exists in the vehicle model. The advantage of using a sequential loop closure technique to reduce the cost of feedback is demonstrated by example.

  19. Health locus of control theory in diabetes: a worthwhile approach in managing diabetic foot ulcers?

    PubMed

    Przybylski, M

    2010-06-01

    The current global epidemic of type two diabetes mellitus has led to an accompanying increase in both foot ulceration and amputations, which pose significant health problems to populations worldwide. If improved treatment options are to be offered, then we clearly need a better understanding of all aspects of this disease. To date the major focus of diabetes research has been on physical factors, which are undeniably important, but there has been little acknowledgement of the significant psychological effects that can influence health and delay wound healing. The 'health locus of control' (HLC) theory, a psychological theory concerning patients' perceptions of how much control they have over life events (both positive and negative) may well be of use in this patient group. It has been suggested that concordance with treatment is improved when patients have a high 'internal' HLC (as measured by a questionnaire), which aligns with the belief that they have greater control over their health. It has further been suggested that through the implementation of 'group-care' education programmes, patients' attitudes can change, with a shift towards higher 'internal' HLC values. Thus a new approach in patient management might be to implement such education programmes, in the hope of improving adherence to treatment regimens and, hence, patient outcomes. To date there has been little conclusive evidence of the application of this theory, and although various studies have been performed in diabetic populations, only one study has been conducted specifically regarding diabetic foot ulcers. Clearly more research is needed.

  20. Recasting the theory of mosquito-borne pathogen transmission dynamics and control

    PubMed Central

    Smith, David L.; Perkins, T. Alex; Reiner, Robert C.; Barker, Christopher M.; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M.; George, Dylan B.; Le Menach, Arnaud; Pulliam, Juliet R. C.; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A. T.; Garcia, Andres J.; Gatton, Michelle L.; Gething, Peter W.; Hartley, David M.; Johnston, Geoffrey; Klein, Eili Y.; Michael, Edwin; Lloyd, Alun L.; Pigott, David M.; Reisen, William K.; Ruktanonchai, Nick; Singh, Brajendra K.; Stoller, Jeremy; Tatem, Andrew J.; Kitron, Uriel; Godfray, H. Charles J.; Cohen, Justin M.; Hay, Simon I.; Scott, Thomas W.

    2014-01-01

    Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross–Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control. PMID:24591453

  1. 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.

  2. Recasting the theory of mosquito-borne pathogen transmission dynamics and control.

    PubMed

    Smith, David L; Perkins, T Alex; Reiner, Robert C; Barker, Christopher M; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M; George, Dylan B; Le Menach, Arnaud; Pulliam, Juliet R C; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A T; Garcia, Andres J; Gatton, Michelle L; Gething, Peter W; Hartley, David M; Johnston, Geoffrey; Klein, Eili Y; Michael, Edwin; Lloyd, Alun L; Pigott, David M; Reisen, William K; Ruktanonchai, Nick; Singh, Brajendra K; Stoller, Jeremy; Tatem, Andrew J; Kitron, Uriel; Godfray, H Charles J; Cohen, Justin M; Hay, Simon I; Scott, Thomas W

    2014-04-01

    Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross-Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control.

  3. A theory of local and global processes which affect solar wind electrons. I - The origin of typical 1 AU velocity distribution functions - Steady state theory

    NASA Technical Reports Server (NTRS)

    Scudder, J. D.; Olbert, S.

    1979-01-01

    A kinetic theory for the velocity distribution of solar wind electrons which illustrates the global and local properties of the solar wind expansion is proposed. By means of the Boltzmann equation with the Krook collision operator accounting for Coulomb collisions, it is found that Coulomb collisions determine the population and shape of the electron distribution function in both the thermal and suprathermal energy regimes. For suprathermal electrons, the cumulative effects of Coulomb interactions are shown to take place on the scale of the heliosphere itself, whereas the Coulomb interactions of thermal electrons occur on a local scale near the point of observation (1 AU). The bifurcation of the electron distribution between thermal and suprathermal electrons is localized to the deep solar corona (1 to 10 solar radii).

  4. Test and theory for piezoelectric actuator-active vibration control of rotating machinery

    NASA Technical Reports Server (NTRS)

    Palazzolo, A. B.; Lin, R. R.; Alexander, R. M.; Kascak, A. F.; Montague, J.

    1989-01-01

    The application of piezoelectric actuators for active vibration control (AVC) of rotating machinery is examined. Theory is derived and the resulting predictions are shown to agree closely with results of tests performed on an air turbine driven-overhung rotor. The test results show significant reduction in unbalance, transient and sub-synchronous responses. Results from a 30-hour endurance test support the AVD system reliability. Various aspects of the electro-mechanical stability of the control system are also discussed and illustrated. Finally, application of the AVC system to an actual jet engine is discussed.

  5. Can the application of control theory assist patient management in rheumatoid arthritis?

    PubMed

    Mann, Cindy

    2010-09-01

    Supporting patient self-management is an important part of the care of patients with rheumatoid arthritis (RA) but patients vary in their capacity and willingness to manage their illness and may feel overwhelmed by the challenge of controlling the impact on their life. This paper discusses the value and importance of control theory and how it might be applied to enhance patients' self-management. Not only does it offer a means of identifying those who might have greatest difficulty in managing their illness, but it also points the way to effective interventions.

  6. Emissions from premixed charge compression ignition (PCCI) combustion and affect on emission control devices

    SciTech Connect

    Parks, II, James E; Kass, Michael D; Huff, Shean P; Barone, Teresa L; Lewis Sr, Samuel Arthur; Prikhodko, Vitaly Y; Storey, John Morse

    2010-01-01

    A light-duty diesel engine has been operated in advanced combustion modes known generally as premixed charge compression ignition (PCCI). The emissions have been characterized for several load and speed combinations. Fewer NO{sub x} and particulate matter (PM) emissions are produced by PCCI, but higher CO and hydrocarbon (HC) emissions result. In addition, the nature of the PM differs from conventional combustion; the PM is smaller and has a much higher soluble organic fraction (SOF) content (68% vs. 30% for conventional combustion). Three catalyst technologies were studied to determine the affects of HECC on catalyst performance; the technologies were a lean NO{sub x} trap (LNT), diesel oxidation catalyst (DOC), and diesel particulate filter (DPF). The LNT benefited greatly from the reduced NO{sub x} emissions associated with PCCI. NO{sub x} capacity requirements are reduced as well as overall tailpipe NO{sub x} levels particularly at low load and temperature conditions where regeneration of the LNT is difficult. The DOC performance requirements for PCCI are more stringent due to the higher CO and HC emissions; however, the DOC was effective at controlling the higher CO and HC emissions at conditions above the light-off temperature. Below light-off, CO and HC emissions are problematic. The study of DPF technology focused on the fuel penalties associated with DPF regeneration or 'desoot' due to the different PM loading rates from PCCI vs. conventional combustion. Less frequent desoot events were required from the lower PM from PCCI and, when used in conjunction with an LNT, the lower PM from less frequent LNT regeneration. The lower desoot frequency leads a {approx}3% fuel penalty for a mixture of PCCI and conventional loads vs. {approx}4% for conventional only combustion.

  7. Cultural influences on the survivorship of families affected by childhood cancer: a case for using family systems theories.

    PubMed

    Yi, Jaehee

    2009-09-01

    This paper uses the family systems perspective to synthesize existing studies on the 3 components of Olson's (2000) Circumplex Model-family cohesion, flexibility, and communication-as they relate to family adaptation to cancer; and to extend the discussion to the cultural influences on these components. Family systems theory was found to be a useful framework for understanding the variance of positive and negative family adaptation in the survivorship of childhood cancer and the cultural impact on the family level variables.

  8. New developments in the application of optimal control theory to therapeutic protocols.

    PubMed

    Bayón, L; Otero, J A; Suárez, P M; Tasis, C

    2016-02-01

    Optimal control theory is one of the most important tools in the development of new therapeutic protocols for treating infections. In this work, we present an algorithm able to deal with high-dimensional problems with bounded controls. The optimal solution is obtained by minimizing a positive-definite treatment cost function. Our method, based on Pontryagin's Minimum Principle and the coordinate cyclic descent method, allows solving problems of varied nature. In this paper, and by way of example, therapeutic enhancement of the immune response to invasion by pathogenic attack is addressed as an optimal control problem. The generic mathematical model used describes the evolution of the disease by means of four non-linear, ordinary differential equations. The model is characterized by the concentration of pathogens, plasma cells, antibodies and a numerical value that indicates the relative characteristic of an organ damaged by disease. From a system theory point of view, drugs can be interpreted as control inputs. Therapies based on separate application of the agents are presented in previous studies. We shall present the more general problem in this paper, considering combined therapies and bounded controls. Finally, we present several numerical simulations.

  9. Spacecraft drag-free attitude control system design with Quantitative Feedback Theory

    NASA Astrophysics Data System (ADS)

    Wu, Shu-Fan; Fertin, Denis

    2008-06-01

    One of the key technologies to be demonstrated on board the LISA Pathfinder spacecraft (S/C) is the drag-free attitude control systems (DFACS), aiming to control the S/C attitude and the S/C test masses relative motion with a precision of the order of the nanometer. This paper explores how the controllers could be designed and tuned with the Quantitative Feedback Theory (QFT). After a summary of the plant dynamics and the control strategy using input decoupling, the various performance specifications are presented and transformed into a set of design criteria expressed as constraints for the controller sensitivity and complementary sensitivity transfer functions of each individual control axis. The QFT technique is then used for designing and tuning the controllers, in particular to perform the trade-off between performances and stability and use the available design margins in the drag-free controllers to meet different performance specifications. Both frequency-domain analysis and time-domain simulation test results are presented to evaluate the performance of controllers designed for different purposes.

  10. 40 CFR 63.1316 - PET and polystyrene affected sources-emissions control provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers.... Compliance can be based on either organic HAP or TOC. (1) The owner or operator of an affected source...) through (b)(1)(iv) of this section. (i) The owner or operator of an existing affected source with...

  11. Investigating Affective Experiences in the Undergraduate Chemistry Laboratory: Students' Perceptions of Control and Responsibility

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Malakpa, Zoebedeh; Bretz, Stacey Lowery

    2016-01-01

    Meaningful learning requires the integration of cognitive and affective learning with the psychomotor, i.e., hands-on learning. The undergraduate chemistry laboratory is an ideal place for meaningful learning to occur. However, accurately characterizing students' affective experiences in the chemistry laboratory can be a very difficult task. While…

  12. Family Affection and Control in Relation to Adolescent Self-Disclosure.

    ERIC Educational Resources Information Center

    Rothblum, Esther D.; Snoek, J. D.

    Examined was the way in which self-disclosure develops, focusing upon the family structure and communication system. It was hypothesized that affection in the family would affect the amount of self-disclosure of subjects to parents and people outside the family, and that there would be a curvilinear relationship between the degree of parental…

  13. Unit Template Synchronous Reference Frame Theory Based Control Algorithm for DSTATCOM

    NASA Astrophysics Data System (ADS)

    Bangarraju, J.; Rajagopal, V.; Jayalaxmi, A.

    2014-04-01

    This article proposes new and simplified unit templates instead of standard phase locked loop (PLL) for Synchronous Reference Frame Theory Control Algorithm (SRFT). The extraction of synchronizing components (sinθ and cosθ) for parks and inverse parks transformation using standard PLL takes more execution time. This execution time in control algorithm delays the extraction of reference source current generation. The standard PLL not only takes more execution time but also increases the reactive power burden on the Distributed Static Compensator (DSTATCOM). This work proposes a unit template based SRFT control algorithm for four-leg insulated gate bipolar transistor based voltage source converter for DSTATCOM in distribution systems. This will reduce the execution time and reactive power burden on the DSTATCOM. The proposed DSTATCOM suppress harmonics, regulates the terminal voltage along with neutral current compensation. The DSTATCOM in distribution systems with proposed control algorithm is modeled and simulated using MATLAB using SIMULINK and Simpower systems toolboxes.

  14. PARKINSON'S DISEASE PATIENTS WITH DOMINANT HEMIBODY AFFECTED BY THE DISEASE RELY MORE ON VISION TO MAINTAIN UPRIGHT POSTURAL CONTROL.

    PubMed

    Lahr, Juliana; Pereira, Marcelo Pinto; Pelicioni, Paulo Henrique Silva; De Morais, Luana Carolina; Gobbi, Lilian Teresa Bucken

    2015-12-01

    This study assesses the association between disease onset side (dominant or non-dominant) and vision on postural control of Parkinson's disease patients. Patient volunteers composed two groups, according to the onset side affected: Dominant group (n=9; M age=66.1 yr., SD=7.2; 6 women, 3 men) and Non-dominant group (n=9; M age=67.4 yr., SD=6.4; 6 women, 3 men). The groups' postural control was assessed by posturography during quiet upright stance in two conditions, Eyes open and Eyes closed. Two-way analyses of variance (ANOVAs; group×condition) with repeated measures for the second factor assessed the differences associated with affected hemibody and vision on postural control. Analyses indicated that patients with the dominant side affected also presented significantly greater variation in center of pressure than those with the non-dominant side affected, mainly in the Eyes closed condition. The results demonstrate a higher reliance on vision in the dominant side, possibly to compensate somatosensory system impairments. These results also highlight the importance of analyzing the hemibody affected by the disease when postural control is assessed in this population.

  15. The ash in forest fire affected soils control the soil losses. Part 1. The pioneer research

    NASA Astrophysics Data System (ADS)

    Cerdà, Artemi; Pereira, Paulo

    2013-04-01

    composition (Pereira and Úbeda, 2010) and Pereira et al., 2012). Some of the new research challenges related to ash impact in the fire affected soils are related to the ash redistribution after the fire, the impact of ash in soil and water chemistry, the temporal changes of soil erosion, the control ash exert on vegetation recovery and the role to be played by ash in the best management of fire affected land. Those topics needs new ideas and new scientists such as Paulo Pereira show in the Part II of this abstract. Acknowledgements, Lithuanian Research Council. Project LITFIRE, Fire effects on Lithuanian soils and ecosystems (MIP-48/2011) and the research projects GL2008-02879/BTE and LEDDRA 243857. References Bodí, M., Mataix-Solera, J., Doerr, S., and Cerdà, A. 2011b. The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma, 160, 599-607. Cerdà, A. 1998a. Postfire dynamics of erosional processes under mediterranean climatic conditions. Z. Geomorphol., 42 (3) 373-398. Cerdà, A. 1998b. Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes, 12, 1031-1042. Cerdà, A., and Doerr, S. H.2010. The effect of ant mounds on overland flow and soil erodibility following a wildfire in eastern Spain. Ecohydrology, 3, 392-401. Cerdà, A., and Doerr, S.H. 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74, 256-263. Pereira, P., and Úbeda, X. 2010. Spatial distribution of heavy metals released from ashes after a wildfire, Journal of Environment Engineering and Landscape Management, 18, 13-22. Pereira, P., Ubeda, X., Martin, D.A. 2012. Fire severity effects on ash chemical composition and extractable elements. Geoderma, 191, 105 - 114. Pérez-Cabello, F., Cerdà, A., de la Riva, J., Echeverría, M.T., García-Martín, A., Ibarra, P., Lasanta, T., Montorio

  16. Proceedings of the Workshop on Applications of Distributed System Theory to the Control of Large Space Structures

    NASA Technical Reports Server (NTRS)

    Rodriguez, G. (Editor)

    1983-01-01

    Two general themes in the control of large space structures are addressed: control theory for distributed parameter systems and distributed control for systems requiring spatially-distributed multipoint sensing and actuation. Topics include modeling and control, stabilization, and estimation and identification.

  17. Internally directed cognition and mindfulness: an integrative perspective derived from predictive and reactive control systems theory

    PubMed Central

    Tops, Mattie; Boksem, Maarten A. S.; Quirin, Markus; IJzerman, Hans; Koole, Sander L.

    2013-01-01

    In the present paper, we will apply the predictive and reactive control systems (PARCS) theory as a framework that integrates competing theories of neural substrates of awareness by describing the “default mode network” (DMN) and anterior insula (AI) as parts of two different behavioral and homeostatic control systems. The DMN, a network that becomes active at rest when there is no external stimulation or task to perform, has been implicated in self-reflective awareness and prospection. By contrast, the AI is associated with awareness and task-related attention. This has led to competing theories stressing the role of the DMN in self-awareness vs. the role of interoceptive and emotional information integration in the AI in awareness of the emotional moment. In PARCS, the respective functions of the DMN and AI in a specific control system explains their association with different qualities of awareness, and how mental states can shift from one state (e.g., prospective self-reflection) to the other (e.g., awareness of the emotional moment) depending on the relative dominance of control systems. These shifts between reactive and predictive control are part of processes that enable the intake of novel information, integration of this novel information within existing knowledge structures, and the creation of a continuous personal context in which novel information can be integrated and understood. As such, PARCS can explain key characteristics of mental states, such as their temporal and spatial focus (e.g., a focus on the here and now vs. the future; a first person vs. a third person perspective). PARCS further relates mental states to brain states and functions, such as activation of the DMN or hemispheric asymmetry in frontal cortical functions. Together, PARCS deepens the understanding of a broad range of mental states, including mindfulness, mind wandering, rumination, autobiographical memory, imagery, and the experience of self. PMID:24904455

  18. Communicative-Based Curriculum Innovations between Theory and Practice: Implications for EFL Curriculum Development and Student Cognitive and Affective Change

    ERIC Educational Resources Information Center

    Shawer, Saad

    2010-01-01

    This qualitative study examines the influence of teacher conceptualisations of communicative language teaching on their actual classroom practice and student cognitive and affective change. The qualitative paradigm underpinned this research at the levels of ontology (multiple teacher realities), epistemology (interaction with, rather than…

  19. Optimal control of open quantum systems: A combined surrogate Hamiltonian optimal control theory approach applied to photochemistry on surfaces

    SciTech Connect

    Asplund, Erik; Kluener, Thorsten

    2012-03-28

    In this paper, control of open quantum systems with emphasis on the control of surface photochemical reactions is presented. A quantum system in a condensed phase undergoes strong dissipative processes. From a theoretical viewpoint, it is important to model such processes in a rigorous way. In this work, the description of open quantum systems is realized within the surrogate Hamiltonian approach [R. Baer and R. Kosloff, J. Chem. Phys. 106, 8862 (1997)]. An efficient and accurate method to find control fields is optimal control theory (OCT) [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998); Y. Ohtsuki, G. Turinici, and H. Rabitz, J. Chem. Phys. 120, 5509 (2004)]. To gain control of open quantum systems, the surrogate Hamiltonian approach and OCT, with time-dependent targets, are combined. Three open quantum systems are investigated by the combined method, a harmonic oscillator immersed in an ohmic bath, CO adsorbed on a platinum surface, and NO adsorbed on a nickel oxide surface. Throughout this paper, atomic units, i.e., ({Dirac_h}/2{pi})=m{sub e}=e=a{sub 0}= 1, have been used unless otherwise stated.

  20. Optimal control of open quantum systems: a combined surrogate hamiltonian optimal control theory approach applied to photochemistry on surfaces.

    PubMed

    Asplund, Erik; Klüner, Thorsten

    2012-03-28

    In this paper, control of open quantum systems with emphasis on the control of surface photochemical reactions is presented. A quantum system in a condensed phase undergoes strong dissipative processes. From a theoretical viewpoint, it is important to model such processes in a rigorous way. In this work, the description of open quantum systems is realized within the surrogate hamiltonian approach [R. Baer and R. Kosloff, J. Chem. Phys. 106, 8862 (1997)]. An efficient and accurate method to find control fields is optimal control theory (OCT) [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998); Y. Ohtsuki, G. Turinici, and H. Rabitz, J. Chem. Phys. 120, 5509 (2004)]. To gain control of open quantum systems, the surrogate hamiltonian approach and OCT, with time-dependent targets, are combined. Three open quantum systems are investigated by the combined method, a harmonic oscillator immersed in an ohmic bath, CO adsorbed on a platinum surface, and NO adsorbed on a nickel oxide surface. Throughout this paper, atomic units, i.e., ℏ = m(e) = e = a(0) = 1, have been used unless otherwise stated.

  1. Control by Preynaptic Correlation: a mechanism affecting information transmission from Ia fibers to motoneurons.

    PubMed

    Rudomin, P; Burke, R E; Núñez, R; Madrid, J; Dutton, H

    1975-03-01

    1. In the unanesthetized spinal cord of the cat, simultaneous intracellular recordings were made from two motoneurons belonging to the gastronemius motor nucleus. 2. Supramaximal iterative stimulation of small branches of the gastrocnemius nerve produced monosynaptic EPSPs (Ia EPSPs) of varying amplitude superimposed on a fluctuating base line. 3. In most cases the variance of the motoneuron membrane potential was increased above base-line levels with a time course approximately matching the Ia EPSP. This suggests that Ia EPSP fluctuations are greater than can be accounted for by the base-line fluctuations alone. 4. For a given series of Ia EPSPs, the smaller responses in the series had about the same decay phase as the larger EPSPs, suggesting that most of the Ia EPSP fluctuations were not due to systematic changes in postsynaptic conductances produced by ongoing activity, but rather to a presynaptic mechanism. 5. Simultaneous recording from two motoneurons showed that base-line fluctuations were positively correlated. In most cases, however, there was an additional increased correlation above base-line levels resembling the time course of the Ia EPSPs, indicating positive correlation between EPSP fluctuations which is attributed to a presynaptic mechanism. 6. Conditioning volleys to group I muscle afferents or to low-threshold cutaneous afferents reduced the variance of the Ia EPSPs and also their correlation in motoneuron pairs, often without changing the mean Ia EPSPs. 7. It is concluded that, in the unanesthetized spinal cord, in addition to the random process which governs transmitter release intrinsic to a given synaptic terminal, there is another stochastic process affecting, in a correlated manner, transmitter release in large sets of Ia synaptic terminals. Most likely, the correlation in transmitter release is achieved by membrane potential fluctuations imposed on the Ia terminal arborizations by ongoing activity of the segmental mechanism mediating

  2. CR-Calculus and adaptive array theory applied to MIMO random vibration control tests

    NASA Astrophysics Data System (ADS)

    Musella, U.; Manzato, S.; Peeters, B.; Guillaume, P.

    2016-09-01

    Performing Multiple-Input Multiple-Output (MIMO) tests to reproduce the vibration environment in a user-defined number of control points of a unit under test is necessary in applications where a realistic environment replication has to be achieved. MIMO tests require vibration control strategies to calculate the required drive signal vector that gives an acceptable replication of the target. This target is a (complex) vector with magnitude and phase information at the control points for MIMO Sine Control tests while in MIMO Random Control tests, in the most general case, the target is a complete spectral density matrix. The idea behind this work is to tailor a MIMO random vibration control approach that can be generalized to other MIMO tests, e.g. MIMO Sine and MIMO Time Waveform Replication. In this work the approach is to use gradient-based procedures over the complex space, applying the so called CR-Calculus and the adaptive array theory. With this approach it is possible to better control the process performances allowing the step-by-step Jacobian Matrix update. The theoretical bases behind the work are followed by an application of the developed method to a two-exciter two-axis system and by performance comparisons with standard methods.

  3. Free-time and fixed end-point optimal control theory in quantum mechanics: application to entanglement generation.

    PubMed

    Mishima, K; Yamashita, K

    2009-01-21

    We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

  4. Free-time and fixed end-point optimal control theory in quantum mechanics: Application to entanglement generation

    NASA Astrophysics Data System (ADS)

    Mishima, K.; Yamashita, K.

    2009-01-01

    We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

  5. Optimal control theory investigation of proprotor/wing response to vertical gust

    NASA Technical Reports Server (NTRS)

    Frick, J. K. D.; Johnson, W.

    1974-01-01

    Optimal control theory is used to design linear state variable feedback to improve the dynamic characteristics of a rotor and cantilever wing representing the tilting proprotor aircraft in cruise flight. The response to a vertical gust and system damping are used as criteria for the open and closed loop performance. The improvement in the dynamic characteristics achievable is examined for a gimballed rotor and for a hingeless rotor design. Several features of the design process are examined, including: (1) using only the wing or only the rotor dynamics in the control system design; (2) the use of a wing flap as well as the rotor controls for inputs; (3) and the performance of the system designed for one velocity at other forward speeds.

  6. Development of a two-dimensional skin friction balance nulling circuit using multivariable control theory

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Patek, Stephen D.

    1988-01-01

    Measurement of planar skin friction forces in aerodynamic testing currently requires installation of two perpendicularly mounted, single-axis balances; consequently, force components must be sensed at two distinct locations. A two-axis instrument developed at the Langley Research Center to overcome this disadvantage allows measurement of a two-dimensional force at one location. This paper describes a feedback-controlled nulling circuit developed for the NASA two-axis balance which, without external compensation, is inherently unstable because of its low friction mechanical design. Linear multivariable control theory is applied to an experimentally validated mathematical model of the balance to synthesize a state-variable feedback control law. Pole placement techniques and computer simulation studies are employed to select eigenvalues which provide ideal transient response with decoupled sensing dynamics.

  7. A manual control theory analysis of vertical situation displays for STOL aircraft

    NASA Technical Reports Server (NTRS)

    Baron, S.; Levison, W. H.

    1973-01-01

    Pilot-vehicle-display systems theory is applied to the analysis of proposed vertical situation displays for manual control in approach-to-landing of a STOL aircraft. The effects of display variables on pilot workload and on total closed-loop system performance was calculated using an optimal-control model for the human operator. The steep approach of an augmentor wing jet STOL aircraft was analyzed. Both random turbulence and mean-wind shears were considered. Linearized perturbation equations were used to describe longitudinal and lateral dynamics of the aircraft. The basic display configuration was one that abstracted the essential status information (including glide-slope and localizer errors) of an EADI display. Proposed flight director displays for both longitudinal and lateral control were also investigated.

  8. Principles of Motor Recovery After Neurological Injury Based on a Motor Control Theory.

    PubMed

    Levin, Mindy F

    2016-01-01

    Problems of neurological rehabilitation are considered based on two levels of the International Classification of Functioning (ICF)-Body Structures and Function level and Activity level-and modulating factors related to the individual and the environment. Specifically, at the Body Structures and Function level, problems addressed include spasticity, muscle weakness, disordered muscle activation patterns and disruptions in coordinated movement. At the Activity level, deficits in multi-joint and multi-segment upper limb reaching movements are reviewed. We address how physiologically well established principles in the control of actions, Threshold Control and Referent Control as outlined in the Equilibrium-Point theory can help advance the understanding of underlying deficits that may limit recovery at each level.

  9. Unhealthy weight control behaviours in adolescent girls: a process model based on self-determination theory.

    PubMed

    Thøgersen-Ntoumani, Cecilie; Ntoumanis, Nikos; Nikitaras, Nikitas

    2010-06-01

    This study used self-determination theory (Deci, E.L., & Ryan, R.M. (2000). The 'what' and 'why' of goal pursuits: Human needs and the self-determination of behavior. Psychological Inquiry, 11, 227-268.) to examine predictors of body image concerns and unhealthy weight control behaviours in a sample of 350 Greek adolescent girls. A process model was tested which proposed that perceptions of parental autonomy support and two life goals (health and image) would predict adolescents' degree of satisfaction of their basic psychological needs. In turn, psychological need satisfaction was hypothesised to negatively predict body image concerns (i.e. drive for thinness and body dissatisfaction) and, indirectly, unhealthy weight control behaviours. The predictions of the model were largely supported indicating that parental autonomy support and adaptive life goals can indirectly impact upon the extent to which female adolescents engage in unhealthy weight control behaviours via facilitating the latter's psychological need satisfaction.

  10. ENGINEERING AND ECONOMIC FACTORS AFFECTING THE INSTALLATION OF CONTROL TECHNOLOGIES FOR MULTIPOLLUTANT STRATEGIES

    EPA Science Inventory

    The report evaluates the engineering and economic factors associated with installing air pollution control technologies to meet the requirements of strategies to control sulfur dioxide (SO2), oxides of nitrogen (NOX), and mercury under the Clear Skies Act multipollutant control s...

  11. A robust rotorcraft flight control system design methodology utilizing quantitative feedback theory

    NASA Technical Reports Server (NTRS)

    Gorder, Peter James

    1993-01-01

    Rotorcraft flight control systems present design challenges which often exceed those associated with fixed-wing aircraft. First, large variations in the response characteristics of the rotorcraft result from the wide range of airspeeds of typical operation (hover to over 100 kts). Second, the assumption of vehicle rigidity often employed in the design of fixed-wing flight control systems is rarely justified in rotorcraft where rotor degrees of freedom can have a significant impact on the system performance and stability. This research was intended to develop a methodology for the design of robust rotorcraft flight control systems. Quantitative Feedback Theory (QFT) was chosen as the basis for the investigation. Quantitative Feedback Theory is a technique which accounts for variability in the dynamic response of the controlled element in the design robust control systems. It was developed to address a Multiple-Input Single-Output (MISO) design problem, and utilizes two degrees of freedom to satisfy the design criteria. Two techniques were examined for extending the QFT MISO technique to the design of a Multiple-Input-Multiple-Output (MIMO) flight control system (FCS) for a UH-60 Black Hawk Helicopter. In the first, a set of MISO systems, mathematically equivalent to the MIMO system, was determined. QFT was applied to each member of the set simultaneously. In the second, the same set of equivalent MISO systems were analyzed sequentially, with closed loop response information from each loop utilized in subsequent MISO designs. The results of each technique were compared, and the advantages of the second, termed Sequential Loop Closure, were clearly evident.

  12. The Effects of Thematic Content of Rheostatically Controlled Visual Subliminals Upon the Receiving Level of the Affective Domain of Learners.

    ERIC Educational Resources Information Center

    Ledford, Bruce R.

    The purpose of the study was to determine the effects of rheostatically controlled visual subliminals on the affective interrelations of a learning task of subjects within a classroom setting. Four groups of students were used. Subjects were unknowingly exposed to a rheostatically projected subliminal message for 30 minutes during otherwise normal…

  13. The Observation of Manual Grasp Actions Affects the Control of Speech: A Combined Behavioral and Transcranial Magnetic Stimulation Study

    ERIC Educational Resources Information Center

    Gentilucci, Maurizio; Campione, Giovanna Cristina; Volta, Riccardo Dalla; Bernardis, Paolo

    2009-01-01

    Does the mirror system affect the control of speech? This issue was addressed in behavioral and Transcranial Magnetic Stimulation (TMS) experiments. In behavioral experiment 1, participants pronounced the syllable /da/ while observing (1) a hand grasping large and small objects with power and precision grasps, respectively, (2) a foot interacting…

  14. Adaptive modeling, identification, and control of dynamic structural systems. I. Theory

    USGS Publications Warehouse

    Safak, Erdal

    1989-01-01

    A concise review of the theory of adaptive modeling, identification, and control of dynamic structural systems based on discrete-time recordings is presented. Adaptive methods have four major advantages over the classical methods: (1) Removal of the noise from the signal is done over the whole frequency band; (2) time-varying characteristics of systems can be tracked; (3) systems with unknown characteristics can be controlled; and (4) a small segment of the data is needed during the computations. Included in the paper are the discrete-time representation of single-input single-output (SISO) systems, models for SISO systems with noise, the concept of stochastic approximation, recursive prediction error method (RPEM) for system identification, and the adaptive control. Guidelines for model selection and model validation and the computational aspects of the method are also discussed in the paper. The present paper is the first of two companion papers. The theory given in the paper is limited to that which is necessary to follow the examples for applications in structural dynamics presented in the second paper.

  15. Diffuse-interface theory for structure formation and release behavior in controlled drug release systems.

    PubMed

    Saylor, David M; Kim, Chang-Soo; Patwardhan, Dinesh V; Warren, James A

    2007-11-01

    A common method of controlling drug release has been to incorporate the drug into a polymer matrix, thereby creating a diffusion barrier that slows the rate of drug release. It has been demonstrated that the internal microstructure of these drug-polymer composites can significantly impact the drug release rate. However, the effect of processing conditions during manufacture on the composite structure and the subsequent effects on release behavior are not well understood. We have developed a diffuse-interface theory for microstructure evolution that is based on interactions between drug, polymer and solvent species, all of which may be present in either crystalline or amorphous states. Because the theory can be applied to almost any specific combination of material species and over a wide range of environmental conditions, it can be used to elucidate and quantify the relationships between processing, microstructure and release response in controlled drug release systems. Calculations based on the theory have now demonstrated that, for a characteristic delivery system, variations in microstructure arising due to changes in either drug loading or processing time, i.e. evaporation rate, could have a significant impact on both the bulk release kinetics and the uniformity of release across the system. In fact, we observed that changes in process time alone can induce differences in bulk release of almost a factor of two and typical non-uniformities of +/-30% during the initial periods of release. Because these substantial variations may have deleterious clinical ramifications, it is critical that both the system microstructure and the control of that microstructure are considered to ensure the device will be both safe and effective in clinical use.

  16. Ability of Stress, Sense of Control, and Self-Theories to Predict Swedish High School Students' Final Grades

    ERIC Educational Resources Information Center

    Ollfors, Marianne; Andersson, Sven Ingmar

    2007-01-01

    The aim of this study was to investigate self-theories (theories of intelligence, confidence in one's intelligence, internal attribution of failure, academic self-efficacy), specific control, and experiencing of stress by means of a questionnaire for 915 Swedish high school students. Factor analysis yielded 6 stress domains (Workload, Psychosocial…

  17. The Gendered Monitoring of Juvenile Delinquents: A Test of Power-Control Theory Using a Retrospective Cohort Study

    ERIC Educational Resources Information Center

    Schulze, Corina; Bryan, Valerie

    2017-01-01

    Through the framework of power-control theory (PCT), we provide a model of juvenile offending that places the gendered-raced treatment of juveniles central to the analysis. We test the theory using a unique sample that is predominately African American, poor, and composed entirely of juvenile offenders. Multivariate models compare the predictive…

  18. Probing the attentional control theory in social anxiety: an emotional saccade task.

    PubMed

    Wieser, Matthias J; Pauli, Paul; Mühlberger, Andreas

    2009-09-01

    Volitional attentional control has been found to rely on prefrontal neuronal circuits. According to the attentional control theory of anxiety, impairment in the volitional control of attention is a prominent feature in anxiety disorders. The present study investigated this assumption in socially anxious individuals using an emotional saccade task with facial expressions (happy, angry, fearful, sad, neutral). The gaze behavior of participants was recorded during the emotional saccade task, in which participants performed either pro- or antisaccades in response to peripherally presented facial expressions. The results show that socially anxious persons have difficulties in inhibiting themselves to reflexively attend to facial expressions: They made more erratic prosaccades to all facial expressions when an antisaccade was required. Thus, these findings indicate impaired attentional control in social anxiety. Overall, the present study shows a deficit of socially anxious individuals in attentional control-for example, in inhibiting the reflexive orienting to neutral as well as to emotional facial expressions. This result may be due to a dysfunction in the prefrontal areas being involved in attentional control.

  19. Theory of agent-based market models with controlled levels of greed and anxiety

    NASA Astrophysics Data System (ADS)

    Papadopoulos, P.; Coolen, A. C. C.

    2010-01-01

    We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.

  20. Application of non-linear control theory to a model of deep brain stimulation.

    PubMed

    Davidson, Clare M; Lowery, Madeleine M; de Paor, Annraoi M

    2011-01-01

    Deep brain stimulation (DBS) effectively alleviates the pathological neural activity associated with Parkinson's disease. Its exact mode of action is not entirely understood. This paper explores theoretically the optimum stimulation parameters necessary to quench oscillations in a neural-mass type model with second order dynamics. This model applies well established nonlinear control system theory to DBS. The analysis here determines the minimum criteria in terms of amplitude and pulse duration of stimulation, necessary to quench the unwanted oscillations in a closed loop system, and outlines the relationship between this model and the actual physiological system.

  1. The Significance of Turning Passive Into Active in Control Mastery Theory

    PubMed Central

    FOREMAN, STEVEN A.

    1996-01-01

    Turning passive into active was first described by Freud but was later given expanded importance by Weiss. This new conceptualization of turning passive into active as an interpersonal communication and test has made a major contribution to the clinical treatment of difficult patients. This article reviews "control mastery" theory and puts its notion of passive-into-active testing into perspective with regard to Freud’s original conception as well as other conceptions, such as identification with the aggressor and projective identification. Formulation and the treatment of patients are illustrated with clinical examples. PMID:22700271

  2. Attentional orienting and executive control are affected by different types of meditation practice.

    PubMed

    Tsai, Min-Hui; Chou, Wei-Lun

    2016-11-01

    Several studies have demonstrated the beneficial effects of meditation on attention. The present study investigated the relationship between focused attention (FA) and open monitoring (OM) meditation skills and the various functions of attention. In Experiment 1, we executed the attention network test and compared the performance of experts on dandao meditation with that of ordinary people on this test. The results indicated that the experts specializing in OM meditation demonstrated greater attentional orienting ability compared with those specializing in FA meditation and the control group. In addition, both expert groups registered improvements in their executive control abilities compared with the control group. In Experiment 2, we trained beginners in FA meditation for 3months. The results showed that the experimental group exhibited significantly enhanced executive control ability. We infer that FA meditation skills promote executive control function and OM meditation skills promote both executive control and attentional orienting functions.

  3. Self-Control, Native Traditionalism, and Native American Substance Use: Testing the Cultural Invariance of a General Theory of Crime

    ERIC Educational Resources Information Center

    Morris, Gregory D.; Wood, Peter B.; Dunaway, R. Gregory

    2006-01-01

    Using a sample of White and Native American high school students, the authors provide a test of (a) self-control theory's invariance thesis and (b) native traditionalism as an explanation of Native American substance use. Self-control significantly influenced all forms of substance use when controlling for race and in race-specific analyses.…

  4. Negative Affectivity, Effortful Control, and Attention to Threat-Relevant Stimuli

    ERIC Educational Resources Information Center

    Lonigan, Christopher J.; Vasey, Michael W.

    2009-01-01

    There is increasing recognition of temperamental influences on risk for psychopathology. Whereas the link between the broad temperament construct of negative affectivity (NA) and problems associated with anxiety and depression is now well-established, the mechanisms through which this link operate are not well understood. One possibility involves…

  5. Anxiety and Affective Control among Distance Language Learners in China and the UK

    ERIC Educational Resources Information Center

    Hurd, Stella; Xiao, Junhong

    2010-01-01

    Foreign language anxiety (FLA) has been the focus of many studies into affect in classroom settings. However, the growing numbers of distance language learners worldwide in recent years calls for greater attention to be paid to this increasingly important constituency of language learners. Following on from Hurd's investigation into FLA with…

  6. 40 CFR 63.1316 - PET and polystyrene affected sources-emissions control provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... reaction section (including emissions from any equipment used to further recover ethylene glycol, but... process vents in the collection of raw material preparation sections within the affected source by... materials preparation section shall, as a whole, be no greater than 0.04 kg organic HAP per Mg of...

  7. The control processes and subjective well-being of Chinese teachers: evidence of convergence with and divergence from the key propositions of the motivational theory of life-span development.

    PubMed

    Wong, Wan-Chi; Li, Yin; Sun, Xiaoyan; Xu, Huanu

    2014-01-01

    An analytical review of the motivational theory of life-span development reveals that this theory has undergone a series of elegant theoretical integrations. Its claim to universality nonetheless brings forth unresolved controversies. With the purpose of scrutinizing the key propositions of this theory, an empirical study was designed to examine the control processes and subjective well-being of Chinese teachers (N = 637). The OPS-Scales (Optimization in Primary and Secondary Control Scales) for the Domain of Teaching were constructed to assess patterns of control processes. Three facets of subjective well-being were investigated with the Positive and Negative Affect Schedule, the Life Satisfaction Scale, and the Subjective Vitality Scale. The results revealed certain aspects of alignment with and certain divergences from the key propositions of the motivational theory of life-span development. Neither "primacy of primary control" nor "primacy of secondary control" was clearly supported. Notably, using different criteria for subjective well-being yielded different subtypes of primary and secondary control as predictors. The hypothesized life-span trajectories of primary and secondary control received limited support. To advance the theory in this area, we recommend incorporating Lakatos' ideas about sophisticated falsification by specifying the hard core of the motivational theory of life-span development and articulating new auxiliary hypotheses.

  8. [Factors affecting the control of blood pressure and lipid levels in patients with cardiovascular disease: the PREseAP Study].

    PubMed

    Orozco-Beltrán, Domingo; Brotons, Carlos; Moral, Irene; Soriano, Nuria; Del Valle, María A; Rodríguez, Ana I; Pepió, Josep M; Pastor, Ana

    2008-03-01

    The aim of this observational study was to identify factors influencing the control of blood pressure (i.e., <140/90 mmHg, or <130/80 mmHg in diabetic patients) and low-density lipoprotein (LDL) cholesterol level (<100 mg/dL) in 1223 patients with cardiovascular disease. Overall, 70.2% of patients were men, and their mean age was 66.4 years. Blood pressure was poorly controlled in 50.9% (95% confidence interval [CI], 46.9%-54.8%) and the LDL cholesterol level was poorly controlled in 60.1% (95% CI, 56.3%-63.9%). Determinants of poor blood pressure control were diabetes, hypertension, no previous diagnosis of heart failure, previous diagnosis of peripheral artery disease or stroke, obesity, and no lipid-lowering treatment. Determinants of poor LDL cholesterol control were no lipid-lowering treatment, no previous diagnosis of ischemic heart disease, no antihypertensive treatment, and dyslipidemia. The factors affecting blood pressure control were different from those affecting LDL cholesterol control, an observation that should be taken into account when implementing treatment recommendations for achieving therapeutic objectives in secondary prevention.

  9. Yes, but are they happy? Effects of trait self-control on affective well-being and life satisfaction.

    PubMed

    Hofmann, Wilhelm; Luhmann, Maike; Fisher, Rachel R; Vohs, Kathleen D; Baumeister, Roy F

    2014-08-01

    Does trait self-control (TSC) predict affective well-being and life satisfaction--positively, negatively, or not? We conducted three studies (Study 1: N = 414, 64% female, Mage = 35.0 years; Study 2: N = 208, 66% female, Mage = 25.24 years; Study 3: N = 234, 61% female, Mage = 34.53 years). The key predictor was TSC, with affective well-being and life satisfaction ratings as key outcomes. Potential explanatory constructs including goal conflict, goal balancing, and emotional distress also were investigated. TSC is positively related to affective well-being and life satisfaction, and managing goal conflict is a key as to why. All studies, moreover, showed that the effect of TSC on life satisfaction is at least partially mediated by affect. Study 1's correlational study established the effect. Study 2's experience sampling approach demonstrated that compared to those low in TSC, those high in TSC experience higher levels of momentary affect even as they experience desire, an effect partially mediated through experiencing lower conflict and emotional distress. Study 3 found evidence for the proposed mechanism--that TSC may boost well-being by helping people avoid frequent conflict and balance vice-virtue conflicts by favoring virtues. Self-control positively contributes to happiness through avoiding and dealing with motivational conflict.

  10. Individual Characteristics Influencing Physicians’ Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism

    PubMed Central

    Mazzetti, Greta; Biolcati, Roberta; Guglielmi, Dina; Vallesi, Caryn; Schaufeli, Wilmar B.

    2016-01-01

    The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands. PMID:27275828

  11. Individual Characteristics Influencing Physicians' Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism.

    PubMed

    Mazzetti, Greta; Biolcati, Roberta; Guglielmi, Dina; Vallesi, Caryn; Schaufeli, Wilmar B

    2016-06-06

    The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands.

  12. Applications of control theory to the dynamics and propagation of cardiac action potentials.

    PubMed

    Muñoz, Laura M; Stockton, Jonathan F; Otani, Niels F

    2010-09-01

    Sudden cardiac arrest is a widespread cause of death in the industrialized world. Most cases of sudden cardiac arrest are due to ventricular fibrillation (VF), a lethal cardiac arrhythmia. Electrophysiological abnormalities such as alternans (a beat-to-beat alternation in action potential duration) and conduction block have been suspected to contribute to the onset of VF. This study focuses on the use of control-systems techniques to analyze and design methods for suppressing these precursor factors. Control-systems tools, specifically controllability analysis and Lyapunov stability methods, were applied to a two-variable Karma model of the action-potential (AP) dynamics of a single cell, to analyze the effectiveness of strategies for suppressing AP abnormalities. State-feedback-integral (SFI) control was then applied to a Purkinje fiber simulated with the Karma model, where only one stimulating electrode was used to affect the system. SFI control converted both discordant alternans and 2:1 conduction block back toward more normal patterns, over a wider range of fiber lengths and pacing intervals compared with a Pyragas-type chaos controller. The advantages conferred by using feedback from multiple locations in the fiber, and using integral (i.e., memory) terms in the controller, are discussed.

  13. Applications of Control Theory to the Dynamics and Propagation of Cardiac Action Potentials

    PubMed Central

    Muñoz, Laura M.; Stockton, Jonathan F.; Otani, Niels F.

    2011-01-01

    Sudden cardiac arrest is a widespread cause of death in the industrialized world. Most cases of sudden cardiac arrest are due to ventricular fibrillation (VF), a lethal cardiac arrhythmia. Electrophysiological abnormalities such as alternans (a beat-to-beat alternation in action potential duration) and conduction block have been suspected to contribute to the onset of VF. This study focuses on the use of control-systems techniques to analyze and design methods for suppressing these precursor factors. Control-systems tools, specifically controllability analysis and Lyapunov stability methods, were applied to a two-variable Karma model of the action-potential (AP) dynamics of a single cell, to analyze the effectiveness of strategies for suppressing AP abnormalities. State-feedback-integral (SFI) control was then applied to a Purkinje fiber simulated with the Karma model, where only one stimulating electrode was used to affect the system. SFI control converted both discordant alternans and 2:1 conduction block back toward more normal patterns, over a wider range of fiber lengths and pacing intervals compared with a Pyragas-type chaos controller. The advantages conferred by using feedback from multiple locations in the fiber, and using integral (i.e., memory) terms in the controller, are discussed. PMID:20407833

  14. A control theory approach to the analysis and synthesis of the experimentally observed motion primitives.

    PubMed

    Nori, Francesco; Frezza, Ruggero

    2005-11-01

    Recent experiments on frogs and rats, have led to the hypothesis that sensory-motor systems are organized into a finite number of linearly combinable modules; each module generates a motor command that drives the system to a predefined equilibrium. Surprisingly, in spite of the infiniteness of different movements that can be realized, there seems to be only a handful of these modules. The structure can be thought of as a vocabulary of "elementary control actions". Admissible controls, which in principle belong to an infinite dimensional space, are reduced to the linear vector space spanned by these elementary controls. In the present paper we address some theoretical questions that arise naturally once a similar structure is applied to the control of nonlinear kinematic chains. First of all, we show how to choose the modules so that the system does not loose its capability of generating a "complete" set of movements. Secondly, we realize a "complete" vocabulary with a minimal number of elementary control actions. Subsequently, we show how to modify the control scheme so as to compensate for parametric changes in the system to be controlled. Remarkably, we construct a set of modules with the property of being invariant with respect to the parameters that model the growth of an individual. Robustness against uncertainties is also considered showing how to optimally choose the modules equilibria so as to compensate for errors affecting the system. Finally, the motion primitive paradigm is extended to locomotion and a related formalization of internal (proprioceptive) and external (exteroceptive) variables is given.

  15. Information-Processing and Perceptions of Control: How Attribution Style Affects Task-Relevant Processing

    ERIC Educational Resources Information Center

    Yeigh, Tony

    2007-01-01

    This study investigated the effects of perceived controllability on information processing within Weiner's (1985, 1986) attributional model of learning. Attributional style was used to identify trait patterns of controllability for 37 university students. Task-relevant feedback on an information-processing task was then manipulated to test for…

  16. Environmental factors affecting efficacy of bifenthrin-treated vegetation for mosquito control.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of pesticide-treated vegetation as a barrier for control of nuisance and disease-bearing mosquitoes has become an option for mosquito management for home owners, public health and mosquito control professionals. Potted wax myrtle and azalea plants were treated with bifenthrin (0.79% AI) at ...

  17. Specific predictive power of automatic spider-related affective associations for controllable and uncontrollable fear responses toward spiders.

    PubMed

    Huijding, Jorg; de Jong, Peter J

    2006-02-01

    This study examined the predictive power of automatically activated spider-related affective associations for automatic and controllable fear responses. The Extrinsic Affective Simon Task (EAST; De Houwer, 2003) was used to indirectly assess automatic spider fear-related associations. The EAST and the Fear of Spiders Questionnaire (FSQ) were used to predict fear responses in 48 female students from Maastricht University with varying levels of spider fear. Results showed that: (i) the EAST best predicted automatic fear responses, whereas (ii) the FSQ best predicted strategic avoidance behavior. These results suggest that indirect measures of automatic associations may have specific predictive power for automatic fear responses.

  18. Modeling the Impact of Control on the Attractiveness of Risk in a Prospect Theory Framework

    PubMed Central

    Young, Diana L.; Goodie, Adam S.; Hall, Daniel B.

    2010-01-01

    Many decisions involve a degree of personal control over event outcomes, which is exerted through one’s knowledge or skill. In three experiments we investigated differences in decision making between prospects based on a) the outcome of random events and b) the outcome of events characterized by control. In Experiment 1, participants estimated certainty equivalents (CEs) for bets based on either random events or the correctness of their answers to U.S. state population questions across the probability spectrum. In Experiment 2, participants estimated CEs for bets based on random events, answers to U.S. state population questions, or answers to questions about 2007 NCAA football game results. Experiment 3 extended the same procedure as Experiment 1 using a within-subjects design. We modeled data from all experiments in a prospect theory framework to establish psychological mechanisms underlying decision behavior. Participants weighted the probabilities associated with bets characterized by control so as to reflect greater risk attractiveness relative to bets based on random events, as evidenced by more elevated weighting functions under conditions of control. This research elucidates possible cognitive mechanisms behind increased risk taking for decisions characterized by control, and implications for various literatures are discussed. PMID:21278906

  19. Altruistic sharing behavior in children: Role of theory of mind and inhibitory control.

    PubMed

    Liu, Buyun; Huang, Zhelan; Xu, Guifeng; Jin, Yu; Chen, Yajun; Li, Xiuhong; Wang, Qingxiong; Song, Shanshan; Jing, Jin

    2016-01-01

    This study aimed to assess altruistic sharing behavior in children aged 3 to 5, 6 to 8, and 9 to 11 years and to explore the involvement of potential cognitive mechanisms, namely theory of mind (ToM) and inhibitory control. A total of 158 children completed a dictator game with stickers as incentives. ToM was evaluated using a false belief task in preschoolers and the Strange Story Test in school-age children. Inhibitory control was assessed in preschoolers with the Day-Night task and in older children with the Stroop Color-Word Test. The result was that 48.10% of children aged 3 to 5 years decided to share, and the percentage rose significantly with increasing age. The difference in altruism level in children who decided to share among the three age groups was nonsignificant. These results suggest that mechanisms underlying the decision to share or not and altruistic behavior may be different. No significant linear relations were found between cognitive processes (i.e., ToM and inhibitory control) and sharing behavior. Surprisingly, 9- to 11-year-olds who shared 3 of 10 stickers performed worse in inhibitory control than did those who shared any other number of stickers. In conclusion, the proportion of children who decided to share, but not the level of altruism, increased with age. ToM was not involved in altruistic sharing, whereas inhibitory control may play a role when deciding how much to share.

  20. Representation, control, or reasoning? Distinct functions for theory of mind within the medial prefrontal cortex.

    PubMed

    Hartwright, Charlotte E; Apperly, Ian A; Hansen, Peter C

    2014-04-01

    The medial pFC (mPFC) is frequently reported to play a central role in Theory of Mind (ToM). However, the contribution of this large cortical region in ToM is not well understood. Combining a novel behavioral task with fMRI, we sought to demonstrate functional divisions between dorsal and rostral mPFC. All conditions of the task required the representation of mental states (beliefs and desires). The level of demands on cognitive control (high vs. low) and the nature of the demands on reasoning (deductive vs. abductive) were varied orthogonally between conditions. Activation in dorsal mPFC was modulated by the need for control, whereas rostral mPFC was modulated by reasoning demands. These findings fit with previously suggested domain-general functions for different parts of mPFC and suggest that these functions are recruited selectively in the service of ToM.

  1. Control of a Flexible Space Antenna: A Finite Dimensional Perspective Based on Distributed Parameter Theory

    NASA Technical Reports Server (NTRS)

    Mingori, D. L.; Gibson, J. S.; Blelloch, P.; Adamian, A.

    1985-01-01

    The methods presented are based on results from infinite dimensional control theory, but they can be described and used in a finite dimensional context. This blend leads to an approach which employs powerful ideas on convergence, and is also quite practical for systems of realistic complexity. Appropriate reduced order models are generated simultaneously with the development of the compensator. The required models change as a function of changes in the performance demanded, sensor and actuator location, inherent damping, disturbances, etc. Thus they are driven by the control and estimation problems at hand. The compensators which emerge are very close to the ideal compensators which would be obtained with a very large order model. However, some simplification is frequently possible. The method of balanced realizations was found to be effective for this purpose.

  2. Optimal control theory (OWEM) applied to a helicopter in the hover and approach phase

    NASA Technical Reports Server (NTRS)

    Born, G. J.; Kai, T.

    1975-01-01

    A major difficulty in the practical application of linear-quadratic regulator theory is how to choose the weighting matrices in quadratic cost functions. The control system design with optimal weighting matrices was applied to a helicopter in the hover and approach phase. The weighting matrices were calculated to extremize the closed loop total system damping subject to constraints on the determinants. The extremization is really a minimization of the effects of disturbances, and interpreted as a compromise between the generalized system accuracy and the generalized system response speed. The trade-off between the accuracy and the response speed is adjusted by a single parameter, the ratio of determinants. By this approach an objective measure can be obtained for the design of a control system. The measure is to be determined by the system requirements.

  3. Building a modular robot control system using passivity and scattering theory

    SciTech Connect

    Anderson, R.J.

    1996-03-01

    This paper analyses the problems and presents solutions for building a modular robot control system. The approach requires modeling the entire robot system using multi-dimensional passive networks, breaking the system into subnetwork ``modules,`` and then discretizing the subnetworks, or n-ports, in a passivity preserving fashion. The main difficulty is the existence of ``algebraic loops`` in the discretized system. This problem is overcome by the use of scattering theory, whereby the inputs and outputs of the n-ports are mapped into wave variables before being discretized. By first segmenting the n-ports into nonlinear memoryless subnetworks and linear dynamic subnetworks and then discretizing using passivity preserving techniques such as Tustin`s method, a complete modular robot control solution is obtained.

  4. On the Use of the Harmonic Linearizaiton Method in the Automatic Control Theory

    NASA Technical Reports Server (NTRS)

    Popov, E. P.

    1957-01-01

    The method of harmonic linearization (harmonic balance), first proposed by N. M. Krylov and N. N. Bogolyubov for the approximate investigation of nonlinear vibrations, has been developed and received wide practical application to problems in the theory of automatic control. Recently, some doubt has been expressed on the legitimacy of application of the method to these problems, and assertions were made on the absence in them of a small parameter of any kind. Nevertheless, the method gives practical, acceptable results and is a simple and powerful means in engineering computations. Hence, the importance of questions arises as to its justification. The underlying principle of the method is the replacement of the given nonlinear equation by a linear equation. In establishing the method, a small parameter is considered whose presence makes it possible to speak, with some degree of approximation, of the solution of this new equation to the solution of the given nonlinear equation. In an article by the author, certain considerations were given on the presence of the small parameter, but this question has not as yet received a final answer. In the present report, a somewhat different approach to the problem is applied that permits: (a) establishing, in the clearest manner, the form of the presence of the small parameter in nonlinear problems of control theory, solvable by the method of harmonic linearization; (b) connecting it with previous intuitive physical concepts (with the "filter property") and extending the class of problems possessing this property; and (c) discussing various generalizations of the method.

  5. Control theory prediction of resolved Cheyne-Stokes respiration in heart failure.

    PubMed

    Sands, Scott A; Edwards, Bradley A; Kee, Kirk; Stuart-Andrews, Christopher; Skuza, Elizabeth M; Roebuck, Teanau; Turton, Anthony; Hamilton, Garun S; Naughton, Matthew T; Berger, Philip J

    2016-11-01

    Cheyne-Stokes respiration (CSR) foretells deleterious outcomes in patients with heart failure. Currently, the size of therapeutic intervention is not guided by the patient's underlying pathophysiology. In theory, the intervention needed to resolve CSR, as a control system instability (loop gain >1), can be predicted knowing the baseline loop gain and how much it falls with therapy.In 12 patients with heart failure, we administered an inspiratory carbon dioxide fraction of 1-3% during CSR (n=95 interventions) as a means to reduce loop gain. We estimated the loop gain on therapy (LGtherapy), using the baseline loop gain (using hyperpnoea length/cycle length) and its expected reduction (18% per 1% inspired carbon dioxide), and tested the specific hypothesis that LGtherapy predicts CSR persistence (LGtherapy >1) versus resolution (LGtherapy <1).As predicted, when LGtherapy >1.0, CSR continued during therapy in 23 out of 25 (92%) trials. A borderline loop gain zone (0.8control theory provides predictive insight into CSR resolution in heart failure. Thus, we now have a means to calculate the size of interventions needed to ameliorate CSR on a patient-by-patient basis.

  6. An examination of network position and childhood relational aggression: integrating resource control and social exchange theories.

    PubMed

    Neal, Jennifer Watling; Cappella, Elise

    2012-01-01

    Applying resource control theory and social exchange theory, we examined the social network conditions under which elementary age children were likely to engage in relational aggression. Data on classroom peer networks and peer-nominated behaviors were collected on 671 second- through fourth-grade children in 34 urban, low-income classrooms. Nested regression models with robust cluster standard errors demonstrated that the association between children's number of relationships and their levels of relational aggression was moderated by the number of relationships that their affiliates had. Children with more peer relationships (i.e., higher network centrality) exhibited higher levels of relational aggression, but only when these relationships were with peers who had fewer connections themselves (i.e., poorly connected peers). This finding remained significant even when controlling for common predictors of relational aggression including gender, overt aggression, prosocial behavior, victimization, social preference, and perceived popularity. Results are discussed in terms of their implications for advancing the literature on childhood relational aggression and their practical applications for identifying children at risk for these behaviors.

  7. Evidence for topographic organization in the cerebellum of motor control versus cognitive and affective processing

    PubMed Central

    Stoodley, Catherine J.; Schmahmann, Jeremy D.

    2010-01-01

    Patients with cerebellar damage often present with the cerebellar motor syndrome of dysmetria, dysarthria and ataxia, yet cerebellar lesions can also result in the cerebellar cognitive affective syndrome, including executive, visual-spatial, and linguistic impairments, and affective dysregulation. We have hypothesized that there is topographic organization in the human cerebellum such that the anterior lobe and lobule VIII contain the representation of the sensorimotor cerebellum; lobules VI and VII of the posterior lobe comprise the cognitive cerebellum; and the posterior vermis is the anatomical substrate of the limbic cerebellum. Here we analyze anatomical, functional neuroimaging, and clinical data to test this hypothesis. We find converging lines of evidence supporting regional organization of motor, cognitive, and limbic behaviors in the cerebellum. The cerebellar motor syndrome results when lesions involve the anterior lobe and parts of lobule VI, interrupting cerebellar communication with cerebral and spinal motor systems. Cognitive impairments occur when posterior lobe lesions affect lobules VI and VII (including Crus I, Crus II, and lobule VIIB), disrupting cerebellar modulation of cognitive loops with cerebral association cortices. Neuropsychiatric disorders manifest when vermis lesions deprive cerebrocerebellar limbic loops of cerebellar input. We consider this functional topography to be a consequence of the differential arrangement of connections of the cerebellum with the spinal cord, brainstem, and cerebral hemispheres, reflecting cerebellar incorporation into the distributed neural circuits subserving movement, cognition, and emotion. These observations provide testable hypotheses for future investigations. PMID:20152963

  8. Individual differences in behavioral activation and cardiac vagal control influence affective startle modification.

    PubMed

    Yang, Xiao; Friedman, Bruce H

    2017-04-01

    The startle response (SR) has a close relationship with stress responses. Startle modification (SRM) has been widely used to study stress disorders (e.g., posttraumatic stress disorder). The framework of the behavioral inhibition and activation systems (BIS/BAS) has been thought to correspond with withdrawal and approach motivational processes underlying affective SRM and can influence stress reactivity. Vagally-mediated cardiac activity as indexed by heart rate variability (HRV) has been associated with SRM and regulatory processes during stress. In the present study, the influence of individual differences in the BIS/BAS and resting HRV on affective SRM were examined. Eighty-six subjects viewed affective pictures while acoustic SR stimuli were delivered. Individual differences in motivation were measured by the BIS/BAS scales. The magnitude of SR was assessed as electromyographic activity of the SR eyeblink during pictures of different valences. Resting HRV was derived from electrocardiography. In contrast to previous studies, the present results showed that startle inhibition and potentiation were related to BAS and HRV, but not to BIS. There was also an interaction of BAS and HRV, indicating that the relationship between HRV and SRM strengthened as BAS scores decreased. The present findings suggest that BAS may relate to both withdrawal and approach, and trait stress reactivity is influenced by BAS and cardiac vagal activity. In addition, BAS moderates the relationship between cardiac vagal activity and SRM. These findings have both theoretical and practical implications for the study of SRM, stress disorders, and health.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  10. Factors affecting prevention and control of viral gastroenteritis outbreaks in care homes.

    PubMed

    Vivancos, R; Trainor, E; Oyinloye, A; Keenan, A

    2012-10-01

    We assess the effect of key care quality indicators on viral gastroenteritis outbreaks and control in care homes using mandatory inspection data collected by a non-departmental public body. Outbreak occurrence was associated with care home size but not with overall quality or individual environmental standards. Care home size, hygiene and infection control standard scores were inversely associated with attack rate in residents, whereas delayed reporting to the local public health agency was associated with higher attack rates.

  11. Quantifying the effect size of changing environmental controls on carbon release from permafrost-affected soils

    NASA Astrophysics Data System (ADS)

    Schaedel, C.; Bader, M. K. F.; Schuur, E. A. G.; Bracho, R. G.; Capek, P.; De Baets, S. L.; Diakova, K.; Ernakovich, J. G.; Hartley, I. P.; Iversen, C. M.; Kane, E. S.; Knoblauch, C.; Lupascu, M.; Natali, S.; Norby, R. J.; O'Donnell, J. A.; Roy Chowdhury, T.; Santruckova, H.; Shaver, G. R.; Sloan, V. L.; Treat, C. C.; Waldrop, M. P.

    2014-12-01

    High-latitude surface air temperatures are rising twice as fast as the global mean, causing permafrost to thaw and thereby exposing large quantities of previously frozen organic carbon (C) to microbial decomposition. Increasing temperatures in high latitude ecosystems not only increase C emissions from previously frozen C in permafrost but also indirectly affect the C cycle through changes in regional and local hydrology. Warmer temperatures increase thawing of ice-rich permafrost, causing land surface subsidence where soils become waterlogged, anoxic conditions prevail and C is released in form of anaerobic CO2 and CH4. Although substrate quality, physical protection, and nutrient availability affect C decomposition, increasing temperatures and changes in surface and sub-surface hydrology are likely the dominant factors affecting the rate and form of C release from permafrost; however, their effect size on C release is poorly quantified. We have compiled a database of 24 incubation studies with soils from active layer and permafrost from across the entire permafrost zone to quantify a) the effect size of increasing temperatures and b) the changes from aerobic to anaerobic environmental soil conditions on C release. Results from two different meta-analyses show that a 10°C increase in temperature increased C release by a factor of two in boreal forest, peatland and tundra ecosystems. Under aerobic incubation conditions, soils released on average three times more C than under anaerobic conditions with large variation among the different ecosystems. While peatlands showed similar amounts of C release under aerobic and anaerobic soil conditions, tundra and boreal forest ecosystems released up to 8 times more C under anoxic conditions. This pan-arctic synthesis shows that boreal forest and tundra soils will have a larger impact on climate change when newly thawed permafrost C decomposes in an aerobic environment compared to an anaerobic environment even when

  12. Can interface features affect aggression resulting from violent video game play? An examination of realistic controller and large screen size.

    PubMed

    Kim, Ki Joon; Sundar, S Shyam

    2013-05-01

    Aggressiveness attributed to violent video game play is typically studied as a function of the content features of the game. However, can interface features of the game also affect aggression? Guided by the General Aggression Model (GAM), we examine the controller type (gun replica vs. mouse) and screen size (large vs. small) as key technological aspects that may affect the state aggression of gamers, with spatial presence and arousal as potential mediators. Results from a between-subjects experiment showed that a realistic controller and a large screen display induced greater aggression, presence, and arousal than a conventional mouse and a small screen display, respectively, and confirmed that trait aggression was a significant predictor of gamers' state aggression. Contrary to GAM, however, arousal showed no effects on aggression; instead, presence emerged as a significant mediator.

  13. An initiator protein for plasmid R6K DNA replication. Mutations affecting the copy-number control.

    PubMed

    Inuzuka, M; Wada, Y

    1988-02-08

    Two kinds of mutations affecting the copy-number control of plasmid R6K were isolated and identified in an initiator pi protein by DNA sequencing. Firstly, a temperature-sensitive replication mutation, ts22, with decreased copy number results in a substitution of threonine to isoleucine at position 138 of the 305-amino-acid pi protein. Secondly, a high-copy-number (cop21) mutant was isolated from this ts mutant and was identified by an alteration of alanine to serine at position 162. This cop21 mutation suppressed the Ts character and was recessive to the wild-type allele in the copy control.

  14. Evaluation of some significant issues affecting trajectory and control management for air-breathing hypersonic vehicles

    NASA Technical Reports Server (NTRS)

    Hattis, Philip D.; Malchow, Harvey L.

    1992-01-01

    Horizontal takeoff airbreathing-propulsion launch vehicles require near-optimal guidance and control which takes into account performance sensitivities to atmospheric characteristics while satisfying physically-derived operational constraints. A generic trajectory/control analysis tool that deepens insight into these considerations has been applied to two versions of a winged-cone vehicle model. Information that is critical to the design and trajectory of these vehicles is derived, and several unusual characteristics of the airbreathing propulsion model are shown to have potentially substantial effects on vehicle dynamics.

  15. Conscious and unconscious reward cues can affect a critical component of executive control.

    PubMed

    Capa, Rémi L; Bustin, Gaëlle M; Cleeremans, Axel; Hansenne, Michel

    2011-01-01

    The present study investigates whether updating an important function of executive control can be driven by unconscious reward cues. Participants had to memorize several numbers and update those numbers independently according to a sequence of arithmetic operations. At the beginning of each trial, a reward (1 euro or 5 cents) was presented, either subliminally or supraliminally. Participants could earn the reward if they found the correct response on the updating task. Results showed better performance when a high (conscious or unconscious) reward was at stake compared to a low reward. This suggests that subliminal information can influence a component process of executive control traditionally thought to require consciousness.

  16. Nutritional status of young children in AIDS-affected households and controls in Uganda.

    PubMed

    Bridge, Andrea; Kipp, Walter; Jhangri, Gian S; Laing, Lory; Konde-Lule, Joseph

    2006-05-01

    This study conducted in Uganda assessed the nutritional status of young children and their disease history in the 3-month period before the study. Two groups of children were randomly selected: the first group consisted of 105 children living in homes where a family member fell sick of AIDS, whereas the second group consisted of 100 children who were living in homes where nobody was affected by AIDS. Acute malnutrition (wasting) was rare. There was no difference in the severity of stunting in the two groups (Z scores, -2.1 versus -2.2, P = 0.70). In those children living in AIDS-affected homes, disease episodes were longer (15.7 versus 11.3 days, P = 0.014), but the frequency of disease occurrence was similar in both groups. Fifty-five percent of all children suffered from moderate to severe malnutrition (stunting). The high stunting rate in early childhood suggests a public nutritional intervention program is recommended.

  17. Soil and Sediment Properties Affecting the Transport and Accumulations of Mercury in a Flood Control Reservoir

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mercury accumulations in some fish species from Grenada Lake in north Mississippi exceed the Food and Drug Administration standards for human consumption. This large flood control reservoir serves as a sink for the Skuna and Yalobusha River watersheds whose highly erodible soils contribute to exces...

  18. Motivating Operations Affect Stimulus Control: A Largely Overlooked Phenomenon in Discrimination Learning

    ERIC Educational Resources Information Center

    Lotfizadeh, Amin D.; Edwards, Timothy L.; Redner, Ryan; Poling, Alan

    2012-01-01

    Several recent studies have explored what Michael (e.g., 1982) termed the "value-altering" effect and the "behavior-altering" effect of motivating operations. One aspect of the behavior-altering effect that has garnered no recent attention involves changes in stimulus control produced by motivating operations. To call attention to this aspect of…

  19. Young Suicide Attempters Compared with a Control Group: Psychological, Affective, and Attitudinal Variables.

    ERIC Educational Resources Information Center

    Simonds, John F.; And Others

    1991-01-01

    Compared to normal controls who had never attempted suicide, suicide attempters (n=45) between 16 and 30 years of age admitted to a general hospital psychiatric ward were significantly more hopeless, depressed, and hostile. The suicide attempts seemed to occur in response to stress. A crisis intervention model was suggested as most appropriate way…

  20. Treatment Preferences Affect the Therapeutic Alliance: Implications for Randomized Controlled Trials

    ERIC Educational Resources Information Center

    Iacoviello, Brian M.; McCarthy, Kevin Scott; Barrett, Marna S.; Rynn, Moira; Gallop, Robert; Barber, Jacques P.

    2007-01-01

    The influence of treatment preferences on the development of the therapeutic alliance was investigated. Seventy-five patients were followed while participating in a randomized controlled trial comparing supportive-expressive psychotherapy with sertraline or pill placebo in the treatment of major depressive disorder. Therapeutic alliance was…